| Current File : //root/postfix-3.2.0/src/smtpd/smtpd_check.c |
/*++
/* NAME
/* smtpd_check 3
/* SUMMARY
/* SMTP client request filtering
/* SYNOPSIS
/* #include "smtpd.h"
/* #include "smtpd_check.h"
/*
/* void smtpd_check_init()
/*
/* int smtpd_check_addr(sender, address, smtputf8)
/* const char *sender;
/* const char *address;
/* int smtputf8;
/*
/* char *smtpd_check_rewrite(state)
/* SMTPD_STATE *state;
/*
/* char *smtpd_check_client(state)
/* SMTPD_STATE *state;
/*
/* char *smtpd_check_helo(state, helohost)
/* SMTPD_STATE *state;
/* char *helohost;
/*
/* char *smtpd_check_mail(state, sender)
/* SMTPD_STATE *state;
/* char *sender;
/*
/* char *smtpd_check_rcpt(state, recipient)
/* SMTPD_STATE *state;
/* char *recipient;
/*
/* char *smtpd_check_etrn(state, destination)
/* SMTPD_STATE *state;
/* char *destination;
/*
/* char *smtpd_check_data(state)
/* SMTPD_STATE *state;
/*
/* char *smtpd_check_eod(state)
/* SMTPD_STATE *state;
/*
/* char *smtpd_check_size(state, size)
/* SMTPD_STATE *state;
/* off_t size;
/*
/* char *smtpd_check_queue(state)
/* SMTPD_STATE *state;
/* DESCRIPTION
/* This module implements additional checks on SMTP client requests.
/* A client request is validated in the context of the session state.
/* The result is either an error response (including the numerical
/* code) or the result is a null pointer in case of success.
/*
/* smtpd_check_init() initializes. This function should be called
/* once during the process life time.
/*
/* smtpd_check_addr() sanity checks an email address and returns
/* non-zero in case of badness. The sender argument provides sender
/* context for address resolution and caching, or a null pointer
/* if information is unavailable.
/*
/* smtpd_check_rewrite() should be called before opening a queue
/* file or proxy connection, in order to establish the proper
/* header address rewriting context.
/*
/* Each of the following routines scrutinizes the argument passed to
/* an SMTP command such as HELO, MAIL FROM, RCPT TO, or scrutinizes
/* the initial client connection request. The administrator can
/* specify what restrictions apply.
/*
/* Restrictions are specified via configuration parameters named
/* \fIsmtpd_{client,helo,sender,recipient}_restrictions.\fR Each
/* configuration parameter specifies a list of zero or more
/* restrictions that are applied in the order as specified.
/* .PP
/* smtpd_check_client() validates the client host name or address.
/* Relevant configuration parameters:
/* .IP smtpd_client_restrictions
/* Restrictions on the names or addresses of clients that may connect
/* to this SMTP server.
/* .PP
/* smtpd_check_helo() validates the hostname provided with the
/* HELO/EHLO commands. Relevant configuration parameters:
/* .IP smtpd_helo_restrictions
/* Restrictions on the hostname that is sent with the HELO/EHLO
/* command.
/* .PP
/* smtpd_check_mail() validates the sender address provided with
/* a MAIL FROM request. Relevant configuration parameters:
/* .IP smtpd_sender_restrictions
/* Restrictions on the sender address that is sent with the MAIL FROM
/* command.
/* .PP
/* smtpd_check_rcpt() validates the recipient address provided
/* with an RCPT TO request. Relevant configuration parameters:
/* .IP smtpd_recipient_restrictions
/* Restrictions on the recipient address that is sent with the RCPT
/* TO command.
/* .IP local_recipient_maps
/* Tables of user names (not addresses) that exist in $mydestination.
/* Mail for local users not in these tables is rejected.
/* .PP
/* smtpd_check_etrn() validates the domain name provided with the
/* ETRN command, and other client-provided information. Relevant
/* configuration parameters:
/* .IP smtpd_etrn_restrictions
/* Restrictions on the hostname that is sent with the HELO/EHLO
/* command.
/* .PP
/* smtpd_check_size() checks if a message with the given size can
/* be received (zero means that the message size is unknown). The
/* message is rejected when
/* the message size exceeds the non-zero bound specified with the
/* \fImessage_size_limit\fR configuration parameter. This is a
/* permanent error.
/*
/* smtpd_check_queue() checks the available queue file system
/* space. The message is rejected when:
/* .IP \(bu
/* The available queue file system space is less than the amount
/* specified with the \fImin_queue_free\fR configuration parameter.
/* This is a temporary error.
/* .IP \(bu
/* The available queue file system space is less than twice the
/* message size limit. This is a temporary error.
/* .PP
/* smtpd_check_data() enforces generic restrictions after the
/* client has sent the DATA command.
/*
/* smtpd_check_eod() enforces generic restrictions after the
/* client has sent the END-OF-DATA command.
/*
/* Arguments:
/* .IP name
/* The client hostname, or \fIunknown\fR.
/* .IP addr
/* The client address.
/* .IP helohost
/* The hostname given with the HELO command.
/* .IP sender
/* The sender address given with the MAIL FROM command.
/* .IP recipient
/* The recipient address given with the RCPT TO or VRFY command.
/* .IP size
/* The message size given with the MAIL FROM command (zero if unknown).
/* BUGS
/* Policies like these should not be hard-coded in C, but should
/* be user-programmable instead.
/* SEE ALSO
/* namadr_list(3) host access control
/* domain_list(3) domain access control
/* fsspace(3) free file system space
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*
/* Wietse Venema
/* Google, Inc.
/* 111 8th Avenue
/* New York, NY 10011, USA
/*
/* TLS support originally by:
/* Lutz Jaenicke
/* BTU Cottbus
/* Allgemeine Elektrotechnik
/* Universitaetsplatz 3-4
/* D-03044 Cottbus, Germany
/*--*/
/* System library. */
#include <sys_defs.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <ctype.h>
#include <stdarg.h>
#include <netdb.h>
#include <setjmp.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#ifdef STRCASECMP_IN_STRINGS_H
#include <strings.h>
#endif
/* Utility library. */
#include <msg.h>
#include <vstring.h>
#include <split_at.h>
#include <fsspace.h>
#include <stringops.h>
#include <valid_hostname.h>
#include <argv.h>
#include <mymalloc.h>
#include <dict.h>
#include <htable.h>
#include <ctable.h>
#include <mac_expand.h>
#include <attr_clnt.h>
#include <myaddrinfo.h>
#include <inet_proto.h>
#include <ip_match.h>
#include <valid_utf8_hostname.h>
#include <midna_domain.h>
#include <mynetworks.h>
/* DNS library. */
#include <dns.h>
/* Global library. */
#include <string_list.h>
#include <namadr_list.h>
#include <domain_list.h>
#include <mail_params.h>
#include <resolve_clnt.h>
#include <mail_error.h>
#include <resolve_local.h>
#include <own_inet_addr.h>
#include <mail_conf.h>
#include <maps.h>
#include <mail_addr_find.h>
#include <match_parent_style.h>
#include <strip_addr.h>
#include <cleanup_user.h>
#include <record.h>
#include <rec_type.h>
#include <mail_proto.h>
#include <mail_addr.h>
#include <verify_clnt.h>
#include <input_transp.h>
#include <is_header.h>
#include <valid_mailhost_addr.h>
#include <dsn_util.h>
#include <conv_time.h>
#include <xtext.h>
#include <smtp_stream.h>
#include <attr_override.h>
/* Application-specific. */
#include "smtpd.h"
#include "smtpd_sasl_glue.h"
#include "smtpd_check.h"
#include "smtpd_dsn_fix.h"
#include "smtpd_resolve.h"
#include "smtpd_expand.h"
/*
* Eject seat in case of parsing problems.
*/
static jmp_buf smtpd_check_buf;
/*
* Results of restrictions. Errors are negative; see dict.h.
*/
#define SMTPD_CHECK_DUNNO 0 /* indifferent */
#define SMTPD_CHECK_OK 1 /* explicitly permit */
#define SMTPD_CHECK_REJECT 2 /* explicitly reject */
/*
* Intermediate results. These are static to avoid unnecessary stress on the
* memory manager routines.
*/
static VSTRING *error_text;
static CTABLE *smtpd_rbl_cache;
static CTABLE *smtpd_rbl_byte_cache;
/*
* Pre-opened SMTP recipient maps so we can reject mail for unknown users.
* XXX This does not belong here and will eventually become part of the
* trivial-rewrite resolver.
*/
static MAPS *local_rcpt_maps;
static MAPS *send_canon_maps;
static MAPS *rcpt_canon_maps;
static MAPS *canonical_maps;
static MAPS *virt_alias_maps;
static MAPS *virt_mailbox_maps;
static MAPS *relay_rcpt_maps;
#ifdef TEST
static STRING_LIST *virt_alias_doms;
static STRING_LIST *virt_mailbox_doms;
#endif
/*
* Response templates for various rbl domains.
*/
static MAPS *rbl_reply_maps;
/*
* Pre-opened sender to login name mapping.
*/
static MAPS *smtpd_sender_login_maps;
/*
* Pre-opened access control lists.
*/
static DOMAIN_LIST *relay_domains;
static NAMADR_LIST *mynetworks_curr;
static NAMADR_LIST *mynetworks_new;
static NAMADR_LIST *perm_mx_networks;
#ifdef USE_TLS
static MAPS *relay_ccerts;
#endif
/*
* How to do parent domain wildcard matching, if any.
*/
static int access_parent_style;
/*
* Pre-parsed restriction lists.
*/
static ARGV *client_restrctions;
static ARGV *helo_restrctions;
static ARGV *mail_restrctions;
static ARGV *relay_restrctions;
static ARGV *rcpt_restrctions;
static ARGV *etrn_restrctions;
static ARGV *data_restrctions;
static ARGV *eod_restrictions;
static HTABLE *smtpd_rest_classes;
static HTABLE *policy_clnt_table;
static HTABLE *map_command_table;
static ARGV *local_rewrite_clients;
/*
* The routine that recursively applies restrictions.
*/
static int generic_checks(SMTPD_STATE *, ARGV *, const char *, const char *, const char *);
/*
* Recipient table check.
*/
static int check_sender_rcpt_maps(SMTPD_STATE *, const char *);
static int check_recipient_rcpt_maps(SMTPD_STATE *, const char *);
static int check_rcpt_maps(SMTPD_STATE *, const char *, const char *,
const char *);
/*
* Tempfail actions;
*/
static int unk_name_tf_act;
static int unk_addr_tf_act;
static int unv_rcpt_tf_act;
static int unv_from_tf_act;
/*
* Optional permit logging.
*/
static STRING_LIST *smtpd_acl_perm_log;
/*
* YASLM.
*/
#define STR vstring_str
#define CONST_STR(x) ((const char *) vstring_str(x))
#define UPDATE_STRING(ptr,val) { if (ptr) myfree(ptr); ptr = mystrdup(val); }
/*
* If some decision can't be made due to a temporary error, then change
* other decisions into deferrals.
*
* XXX Deferrals can be postponed only with restrictions that are based on
* client-specified information: this restricts their use to parameters
* given in HELO, MAIL FROM, RCPT TO commands.
*
* XXX Deferrals must not be postponed after client hostname lookup failure.
* The reason is that the effect of access tables may depend on whether a
* client hostname is available or not. Thus, the reject_unknown_client
* restriction must defer immediately when lookup fails, otherwise incorrect
* results happen with:
*
* reject_unknown_client, hostname-based white-list, reject
*
* XXX With warn_if_reject, don't raise the defer_if_permit flag when a
* reject-style restriction fails. Instead, log the warning for the
* resulting defer message.
*
* XXX With warn_if_reject, do raise the defer_if_reject flag when a
* permit-style restriction fails. Otherwise, we could reject legitimate
* mail.
*/
static int PRINTFLIKE(5, 6) defer_if(SMTPD_DEFER *, int, int, const char *, const char *,...);
static int PRINTFLIKE(5, 6) smtpd_check_reject(SMTPD_STATE *, int, int, const char *, const char *,...);
#define DEFER_IF_REJECT2(state, class, code, dsn, fmt, a1, a2) \
defer_if(&(state)->defer_if_reject, (class), (code), (dsn), (fmt), (a1), (a2))
#define DEFER_IF_REJECT3(state, class, code, dsn, fmt, a1, a2, a3) \
defer_if(&(state)->defer_if_reject, (class), (code), (dsn), (fmt), (a1), (a2), (a3))
#define DEFER_IF_REJECT4(state, class, code, dsn, fmt, a1, a2, a3, a4) \
defer_if(&(state)->defer_if_reject, (class), (code), (dsn), (fmt), (a1), (a2), (a3), (a4))
/*
* The following choose between DEFER_IF_PERMIT (only if warn_if_reject is
* turned off) and plain DEFER. See tempfail_actions[] below for the mapping
* from names to numeric action code.
*/
#define DEFER_ALL_ACT 0
#define DEFER_IF_PERMIT_ACT 1
#define DEFER_IF_PERMIT2(type, state, class, code, dsn, fmt, a1, a2) \
(((state)->warn_if_reject == 0 && (type) != 0) ? \
defer_if(&(state)->defer_if_permit, (class), (code), (dsn), (fmt), (a1), (a2)) \
: \
smtpd_check_reject((state), (class), (code), (dsn), (fmt), (a1), (a2)))
#define DEFER_IF_PERMIT3(type, state, class, code, dsn, fmt, a1, a2, a3) \
(((state)->warn_if_reject == 0 && (type) != 0) ? \
defer_if(&(state)->defer_if_permit, (class), (code), (dsn), (fmt), (a1), (a2), (a3)) \
: \
smtpd_check_reject((state), (class), (code), (dsn), (fmt), (a1), (a2), (a3)))
#define DEFER_IF_PERMIT4(type, state, class, code, dsn, fmt, a1, a2, a3, a4) \
(((state)->warn_if_reject == 0 && (type) != 0) ? \
defer_if(&(state)->defer_if_permit, (class), (code), (dsn), (fmt), (a1), (a2), (a3), (a4)) \
: \
smtpd_check_reject((state), (class), (code), (dsn), (fmt), (a1), (a2), (a3), (a4)))
/*
* Cached RBL lookup state.
*/
typedef struct {
char *txt; /* TXT content or NULL */
DNS_RR *a; /* A records */
} SMTPD_RBL_STATE;
static void *rbl_pagein(const char *, void *);
static void rbl_pageout(void *, void *);
static void *rbl_byte_pagein(const char *, void *);
static void rbl_byte_pageout(void *, void *);
/*
* Context for RBL $name expansion.
*/
typedef struct {
SMTPD_STATE *state; /* general state */
char *domain; /* query domain */
const char *what; /* rejected value */
const char *class; /* name of rejected value */
const char *txt; /* randomly selected trimmed TXT rr */
} SMTPD_RBL_EXPAND_CONTEXT;
/*
* Multiplication factor for free space check. Free space must be at least
* smtpd_space_multf * message_size_limit.
*/
double smtpd_space_multf = 1.5;
/*
* SMTPD policy client. Most attributes are ATTR_CLNT attributes.
*/
typedef struct {
ATTR_CLNT *client; /* client handle */
char *def_action; /* default action */
char *policy_context; /* context of policy request */
} SMTPD_POLICY_CLNT;
/*
* Table-driven parsing of main.cf parameter overrides for specific policy
* clients. We derive the override names from the corresponding main.cf
* parameter names by skipping the redundant "smtpd_policy_service_" prefix.
*/
static ATTR_OVER_TIME time_table[] = {
21 + VAR_SMTPD_POLICY_TMOUT, DEF_SMTPD_POLICY_TMOUT, 0, 1, 0,
21 + VAR_SMTPD_POLICY_IDLE, DEF_SMTPD_POLICY_IDLE, 0, 1, 0,
21 + VAR_SMTPD_POLICY_TTL, DEF_SMTPD_POLICY_TTL, 0, 1, 0,
21 + VAR_SMTPD_POLICY_TRY_DELAY, DEF_SMTPD_POLICY_TRY_DELAY, 0, 1, 0,
0,
};
static ATTR_OVER_INT int_table[] = {
21 + VAR_SMTPD_POLICY_REQ_LIMIT, 0, 0, 0,
21 + VAR_SMTPD_POLICY_TRY_LIMIT, 0, 1, 0,
0,
};
static ATTR_OVER_STR str_table[] = {
21 + VAR_SMTPD_POLICY_DEF_ACTION, 0, 1, 0,
21 + VAR_SMTPD_POLICY_CONTEXT, 0, 1, 0,
0,
};
#define link_override_table_to_variable(table, var) \
do { table[var##_offset].target = &var; } while (0)
#define smtpd_policy_tmout_offset 0
#define smtpd_policy_idle_offset 1
#define smtpd_policy_ttl_offset 2
#define smtpd_policy_try_delay_offset 3
#define smtpd_policy_req_limit_offset 0
#define smtpd_policy_try_limit_offset 1
#define smtpd_policy_def_action_offset 0
#define smtpd_policy_context_offset 1
/* policy_client_register - register policy service endpoint */
static void policy_client_register(const char *name)
{
static const char myname[] = "policy_client_register";
SMTPD_POLICY_CLNT *policy_client;
char *saved_name = 0;
const char *policy_name = 0;
char *cp;
const char *sep = CHARS_COMMA_SP;
const char *parens = CHARS_BRACE;
char *err;
if (policy_clnt_table == 0)
policy_clnt_table = htable_create(1);
if (htable_find(policy_clnt_table, name) == 0) {
/*
* Allow per-service overrides for main.cf global settings.
*/
int smtpd_policy_tmout = var_smtpd_policy_tmout;
int smtpd_policy_idle = var_smtpd_policy_idle;
int smtpd_policy_ttl = var_smtpd_policy_ttl;
int smtpd_policy_try_delay = var_smtpd_policy_try_delay;
int smtpd_policy_req_limit = var_smtpd_policy_req_limit;
int smtpd_policy_try_limit = var_smtpd_policy_try_limit;
const char *smtpd_policy_def_action = var_smtpd_policy_def_action;
const char *smtpd_policy_context = var_smtpd_policy_context;
link_override_table_to_variable(time_table, smtpd_policy_tmout);
link_override_table_to_variable(time_table, smtpd_policy_idle);
link_override_table_to_variable(time_table, smtpd_policy_ttl);
link_override_table_to_variable(time_table, smtpd_policy_try_delay);
link_override_table_to_variable(int_table, smtpd_policy_req_limit);
link_override_table_to_variable(int_table, smtpd_policy_try_limit);
link_override_table_to_variable(str_table, smtpd_policy_def_action);
link_override_table_to_variable(str_table, smtpd_policy_context);
if (*name == parens[0]) {
cp = saved_name = mystrdup(name);
if ((err = extpar(&cp, parens, EXTPAR_FLAG_NONE)) != 0)
msg_fatal("policy service syntax error: %s", cp);
if ((policy_name = mystrtok(&cp, sep)) == 0)
msg_fatal("empty policy service: \"%s\"", name);
attr_override(cp, sep, parens,
CA_ATTR_OVER_TIME_TABLE(time_table),
CA_ATTR_OVER_INT_TABLE(int_table),
CA_ATTR_OVER_STR_TABLE(str_table),
CA_ATTR_OVER_END);
} else {
policy_name = name;
}
if (msg_verbose)
msg_info("%s: name=\"%s\" default_action=\"%s\" max_idle=%d "
"max_ttl=%d request_limit=%d retry_delay=%d "
"timeout=%d try_limit=%d policy_context=\"%s\"",
myname, policy_name, smtpd_policy_def_action,
smtpd_policy_idle, smtpd_policy_ttl,
smtpd_policy_req_limit, smtpd_policy_try_delay,
smtpd_policy_tmout, smtpd_policy_try_limit,
smtpd_policy_context);
/*
* Create the client.
*/
policy_client = (SMTPD_POLICY_CLNT *) mymalloc(sizeof(*policy_client));
policy_client->client = attr_clnt_create(policy_name,
smtpd_policy_tmout,
smtpd_policy_idle,
smtpd_policy_ttl);
attr_clnt_control(policy_client->client,
ATTR_CLNT_CTL_REQ_LIMIT, smtpd_policy_req_limit,
ATTR_CLNT_CTL_TRY_LIMIT, smtpd_policy_try_limit,
ATTR_CLNT_CTL_TRY_DELAY, smtpd_policy_try_delay,
ATTR_CLNT_CTL_END);
policy_client->def_action = mystrdup(smtpd_policy_def_action);
policy_client->policy_context = mystrdup(smtpd_policy_context);
htable_enter(policy_clnt_table, name, (void *) policy_client);
if (saved_name)
myfree(saved_name);
}
}
/* command_map_register - register access table for maps lookup */
static void command_map_register(const char *name)
{
MAPS *maps;
if (map_command_table == 0)
map_command_table = htable_create(1);
if (htable_find(map_command_table, name) == 0) {
maps = maps_create(name, name, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
(void) htable_enter(map_command_table, name, (void *) maps);
}
}
/* smtpd_check_parse - pre-parse restrictions */
static ARGV *smtpd_check_parse(int flags, const char *checks)
{
char *saved_checks = mystrdup(checks);
ARGV *argv = argv_alloc(1);
char *bp = saved_checks;
char *name;
char *last = 0;
/*
* Pre-parse the restriction list, and open any dictionaries that we
* encounter. Dictionaries must be opened before entering the chroot
* jail.
*/
#define SMTPD_CHECK_PARSE_POLICY (1<<0)
#define SMTPD_CHECK_PARSE_MAPS (1<<1)
#define SMTPD_CHECK_PARSE_ALL (~0)
while ((name = mystrtokq(&bp, CHARS_COMMA_SP, CHARS_BRACE)) != 0) {
argv_add(argv, name, (char *) 0);
if ((flags & SMTPD_CHECK_PARSE_POLICY)
&& last && strcasecmp(last, CHECK_POLICY_SERVICE) == 0)
policy_client_register(name);
else if ((flags & SMTPD_CHECK_PARSE_MAPS) && strchr(name, ':') != 0) {
command_map_register(name);
}
last = name;
}
argv_terminate(argv);
/*
* Cleanup.
*/
myfree(saved_checks);
return (argv);
}
#ifndef TEST
/* has_required - make sure required restriction is present */
static int has_required(ARGV *restrictions, const char **required)
{
char **rest;
const char **reqd;
ARGV *expansion;
/*
* Recursively check list membership.
*/
for (rest = restrictions->argv; *rest; rest++) {
if (strcasecmp(*rest, WARN_IF_REJECT) == 0 && rest[1] != 0) {
rest += 1;
continue;
}
if (strcasecmp(*rest, PERMIT_ALL) == 0) {
if (rest[1] != 0)
msg_warn("restriction `%s' after `%s' is ignored",
rest[1], rest[0]);
return (0);
}
for (reqd = required; *reqd; reqd++)
if (strcasecmp(*rest, *reqd) == 0)
return (1);
/* XXX This lookup operation should not be case-sensitive. */
if ((expansion = (ARGV *) htable_find(smtpd_rest_classes, *rest)) != 0)
if (has_required(expansion, required))
return (1);
}
return (0);
}
/* fail_required - handle failure to use required restriction */
static void fail_required(const char *name, const char **required)
{
const char *myname = "fail_required";
const char **reqd;
VSTRING *example;
/*
* Sanity check.
*/
if (required[0] == 0)
msg_panic("%s: null required list", myname);
/*
* Go bust.
*/
example = vstring_alloc(10);
for (reqd = required; *reqd; reqd++)
vstring_sprintf_append(example, "%s%s", *reqd,
reqd[1] == 0 ? "" : reqd[2] == 0 ? " or " : ", ");
msg_fatal("in parameter %s, specify at least one working instance of: %s",
name, STR(example));
}
#endif
/* smtpd_check_init - initialize once during process lifetime */
void smtpd_check_init(void)
{
char *saved_classes;
const char *name;
const char *value;
char *cp;
#ifndef TEST
static const char *rcpt_required[] = {
REJECT_UNAUTH_DEST,
DEFER_UNAUTH_DEST,
REJECT_ALL,
DEFER_ALL,
DEFER_IF_PERMIT,
CHECK_RELAY_DOMAINS,
0,
};
#endif
static NAME_CODE tempfail_actions[] = {
DEFER_ALL, DEFER_ALL_ACT,
DEFER_IF_PERMIT, DEFER_IF_PERMIT_ACT,
0, -1,
};
/*
* Pre-open access control lists before going to jail.
*/
mynetworks_curr =
namadr_list_init(VAR_MYNETWORKS, MATCH_FLAG_RETURN
| match_parent_style(VAR_MYNETWORKS), var_mynetworks);
mynetworks_new =
namadr_list_init(VAR_MYNETWORKS, MATCH_FLAG_RETURN
| match_parent_style(VAR_MYNETWORKS), mynetworks_host());
relay_domains =
domain_list_init(VAR_RELAY_DOMAINS,
match_parent_style(VAR_RELAY_DOMAINS),
var_relay_domains);
perm_mx_networks =
namadr_list_init(VAR_PERM_MX_NETWORKS, MATCH_FLAG_RETURN
| match_parent_style(VAR_PERM_MX_NETWORKS),
var_perm_mx_networks);
#ifdef USE_TLS
relay_ccerts = maps_create(VAR_RELAY_CCERTS, var_smtpd_relay_ccerts,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX);
#endif
/*
* Pre-parse and pre-open the recipient maps.
*/
local_rcpt_maps = maps_create(VAR_LOCAL_RCPT_MAPS, var_local_rcpt_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
send_canon_maps = maps_create(VAR_SEND_CANON_MAPS, var_send_canon_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
rcpt_canon_maps = maps_create(VAR_RCPT_CANON_MAPS, var_rcpt_canon_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
canonical_maps = maps_create(VAR_CANONICAL_MAPS, var_canonical_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
virt_alias_maps = maps_create(VAR_VIRT_ALIAS_MAPS, var_virt_alias_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
virt_mailbox_maps = maps_create(VAR_VIRT_MAILBOX_MAPS,
var_virt_mailbox_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
relay_rcpt_maps = maps_create(VAR_RELAY_RCPT_MAPS, var_relay_rcpt_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
#ifdef TEST
virt_alias_doms = string_list_init(VAR_VIRT_ALIAS_DOMS, MATCH_FLAG_NONE,
var_virt_alias_doms);
virt_mailbox_doms = string_list_init(VAR_VIRT_MAILBOX_DOMS, MATCH_FLAG_NONE,
var_virt_mailbox_doms);
#endif
access_parent_style = match_parent_style(SMTPD_ACCESS_MAPS);
/*
* Templates for RBL rejection replies.
*/
rbl_reply_maps = maps_create(VAR_RBL_REPLY_MAPS, var_rbl_reply_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
/*
* Sender to login name mapping.
*/
smtpd_sender_login_maps = maps_create(VAR_SMTPD_SND_AUTH_MAPS,
var_smtpd_snd_auth_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
/*
* error_text is used for returning error responses.
*/
error_text = vstring_alloc(10);
/*
* Initialize the resolved address cache. Note: the cache persists across
* SMTP sessions so we cannot make it dependent on session state.
*/
smtpd_resolve_init(100);
/*
* Initialize the RBL lookup cache. Note: the cache persists across SMTP
* sessions so we cannot make it dependent on session state.
*/
smtpd_rbl_cache = ctable_create(100, rbl_pagein, rbl_pageout, (void *) 0);
smtpd_rbl_byte_cache = ctable_create(1000, rbl_byte_pagein,
rbl_byte_pageout, (void *) 0);
/*
* Pre-parse the restriction lists. At the same time, pre-open tables
* before going to jail.
*/
client_restrctions = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
var_client_checks);
helo_restrctions = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
var_helo_checks);
mail_restrctions = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
var_mail_checks);
relay_restrctions = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
var_relay_checks);
rcpt_restrctions = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
var_rcpt_checks);
etrn_restrctions = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
var_etrn_checks);
data_restrctions = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
var_data_checks);
eod_restrictions = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
var_eod_checks);
/*
* Parse the pre-defined restriction classes.
*/
smtpd_rest_classes = htable_create(1);
if (*var_rest_classes) {
cp = saved_classes = mystrdup(var_rest_classes);
while ((name = mystrtok(&cp, CHARS_COMMA_SP)) != 0) {
if ((value = mail_conf_lookup_eval(name)) == 0 || *value == 0)
msg_fatal("restriction class `%s' needs a definition", name);
/* XXX This store operation should not be case-sensitive. */
htable_enter(smtpd_rest_classes, name,
(void *) smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
value));
}
myfree(saved_classes);
}
/*
* This is the place to specify definitions for complex restrictions such
* as check_relay_domains in terms of more elementary restrictions.
*/
#if 0
htable_enter(smtpd_rest_classes, "check_relay_domains",
smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
"permit_mydomain reject_unauth_destination"));
#endif
htable_enter(smtpd_rest_classes, REJECT_SENDER_LOGIN_MISMATCH,
(void *) smtpd_check_parse(SMTPD_CHECK_PARSE_ALL,
REJECT_AUTH_SENDER_LOGIN_MISMATCH
" " REJECT_UNAUTH_SENDER_LOGIN_MISMATCH));
/*
* People screw up the relay restrictions too often. Require that they
* list at least one restriction that rejects mail by default. We allow
* relay restrictions to be empty for sites that require backwards
* compatibility.
*/
#ifndef TEST
if (!has_required(rcpt_restrctions, rcpt_required)
&& !has_required(relay_restrctions, rcpt_required))
fail_required(VAR_RELAY_CHECKS " or " VAR_RCPT_CHECKS, rcpt_required);
#endif
/*
* Local rewrite policy.
*/
local_rewrite_clients = smtpd_check_parse(SMTPD_CHECK_PARSE_MAPS,
var_local_rwr_clients);
/*
* Tempfail_actions.
*
* XXX This name-to-number mapping should be encapsulated in a separate
* mail_conf_name_code.c module.
*/
if ((unk_name_tf_act = name_code(tempfail_actions, NAME_CODE_FLAG_NONE,
var_unk_name_tf_act)) < 0)
msg_fatal("bad configuration: %s = %s",
VAR_UNK_NAME_TF_ACT, var_unk_name_tf_act);
if ((unk_addr_tf_act = name_code(tempfail_actions, NAME_CODE_FLAG_NONE,
var_unk_addr_tf_act)) < 0)
msg_fatal("bad configuration: %s = %s",
VAR_UNK_ADDR_TF_ACT, var_unk_addr_tf_act);
if ((unv_rcpt_tf_act = name_code(tempfail_actions, NAME_CODE_FLAG_NONE,
var_unv_rcpt_tf_act)) < 0)
msg_fatal("bad configuration: %s = %s",
VAR_UNV_RCPT_TF_ACT, var_unv_rcpt_tf_act);
if ((unv_from_tf_act = name_code(tempfail_actions, NAME_CODE_FLAG_NONE,
var_unv_from_tf_act)) < 0)
msg_fatal("bad configuration: %s = %s",
VAR_UNV_FROM_TF_ACT, var_unv_from_tf_act);
if (msg_verbose) {
msg_info("%s = %s", VAR_UNK_NAME_TF_ACT, tempfail_actions[unk_name_tf_act].name);
msg_info("%s = %s", VAR_UNK_ADDR_TF_ACT, tempfail_actions[unk_addr_tf_act].name);
msg_info("%s = %s", VAR_UNV_RCPT_TF_ACT, tempfail_actions[unv_rcpt_tf_act].name);
msg_info("%s = %s", VAR_UNV_FROM_TF_ACT, tempfail_actions[unv_from_tf_act].name);
}
/*
* Optional permit logging.
*/
smtpd_acl_perm_log = string_list_init(VAR_SMTPD_ACL_PERM_LOG,
MATCH_FLAG_RETURN,
var_smtpd_acl_perm_log);
}
/* log_whatsup - log as much context as we have */
static void log_whatsup(SMTPD_STATE *state, const char *whatsup,
const char *text)
{
VSTRING *buf = vstring_alloc(100);
vstring_sprintf(buf, "%s: %s: %s from %s: %s;",
state->queue_id ? state->queue_id : "NOQUEUE",
whatsup, state->where, state->namaddr, text);
if (state->sender)
vstring_sprintf_append(buf, " from=<%s>", state->sender);
if (state->recipient)
vstring_sprintf_append(buf, " to=<%s>", state->recipient);
if (state->protocol)
vstring_sprintf_append(buf, " proto=%s", state->protocol);
if (state->helo_name)
vstring_sprintf_append(buf, " helo=<%s>", state->helo_name);
msg_info("%s", STR(buf));
vstring_free(buf);
}
/* smtpd_acl_permit - permit request with optional logging */
static int PRINTFLIKE(5, 6) smtpd_acl_permit(SMTPD_STATE *state,
const char *action,
const char *reply_class,
const char *reply_name,
const char *format,...)
{
const char myname[] = "smtpd_acl_permit";
va_list ap;
const char *whatsup;
#ifdef notdef
#define NO_PRINT_ARGS ""
#else
#define NO_PRINT_ARGS "%s", ""
#endif
/*
* First, find out if (and how) this permit action should be logged.
*/
if (msg_verbose)
msg_info("%s: checking %s settings", myname, VAR_SMTPD_ACL_PERM_LOG);
if (state->defer_if_permit.active) {
/* This action is overruled. Do not log. */
whatsup = 0;
} else if (string_list_match(smtpd_acl_perm_log, action) != 0) {
/* This is not a test. Logging is enabled. */
whatsup = "permit";
} else {
/* This is not a test. Logging is disabled. */
whatsup = 0;
}
if (whatsup != 0) {
vstring_sprintf(error_text, "action=%s for %s=%s",
action, reply_class, reply_name);
if (format && *format) {
vstring_strcat(error_text, " ");
va_start(ap, format);
vstring_vsprintf_append(error_text, format, ap);
va_end(ap);
}
log_whatsup(state, whatsup, STR(error_text));
} else {
if (msg_verbose)
msg_info("%s: %s: no match", myname, VAR_SMTPD_ACL_PERM_LOG);
}
return (SMTPD_CHECK_OK);
}
/* smtpd_check_reject - do the boring things that must be done */
static int smtpd_check_reject(SMTPD_STATE *state, int error_class,
int code, const char *dsn,
const char *format,...)
{
va_list ap;
int warn_if_reject;
const char *whatsup;
/*
* Do not reject mail if we were asked to warn only. However,
* configuration/software/data errors cannot be converted into warnings.
*/
if (state->warn_if_reject && error_class != MAIL_ERROR_SOFTWARE
&& error_class != MAIL_ERROR_RESOURCE
&& error_class != MAIL_ERROR_DATA) {
warn_if_reject = 1;
whatsup = "reject_warning";
} else {
warn_if_reject = 0;
whatsup = "reject";
}
/*
* Update the error class mask, and format the response. XXX What about
* multi-line responses? For now we cheat and send whitespace.
*
* Format the response before complaining about configuration errors, so
* that we can show the error in context.
*/
state->error_mask |= error_class;
vstring_sprintf(error_text, "%d %s ", code, dsn);
va_start(ap, format);
vstring_vsprintf_append(error_text, format, ap);
va_end(ap);
/*
* Validate the response, that is, the response must begin with a
* three-digit status code, and the first digit must be 4 or 5. If the
* response is bad, log a warning and send a generic response instead.
*/
if (code < 400 || code > 599) {
msg_warn("SMTP reply code configuration error: %s", STR(error_text));
vstring_strcpy(error_text, "450 4.7.1 Service unavailable");
}
if (!dsn_valid(STR(error_text) + 4)) {
msg_warn("DSN detail code configuration error: %s", STR(error_text));
vstring_strcpy(error_text, "450 4.7.1 Service unavailable");
}
/*
* Ensure RFC compliance. We could do this inside smtpd_chat_reply() and
* switch to multi-line for long replies.
*/
vstring_truncate(error_text, 510);
printable(STR(error_text), ' ');
/*
* Force this rejection into deferral because of some earlier temporary
* error that may have prevented us from accepting mail, and report the
* earlier problem instead.
*/
if (!warn_if_reject && state->defer_if_reject.active && STR(error_text)[0] == '5') {
state->warn_if_reject = state->defer_if_reject.active = 0;
return (smtpd_check_reject(state, state->defer_if_reject.class,
state->defer_if_reject.code,
STR(state->defer_if_reject.dsn),
"%s", STR(state->defer_if_reject.reason)));
}
/*
* Soft bounce safety net.
*
* XXX The code below also appears in the Postfix SMTP server reply output
* routine. It is duplicated here in order to avoid discrepancies between
* the reply codes that are shown in "reject" logging and the reply codes
* that are actually sent to the SMTP client.
*
* Implementing the soft_bounce safety net in the SMTP server reply output
* routine has the advantage that it covers all 5xx replies, including
* SMTP protocol or syntax errors, which makes soft_bounce great for
* non-destructive tests (especially by people who are paranoid about
* losing mail).
*
* We could eliminate the code duplication and implement the soft_bounce
* safety net only in the code below. But then the safety net would cover
* the UCE restrictions only. This would be at odds with documentation
* which says soft_bounce changes all 5xx replies into 4xx ones.
*/
if (var_soft_bounce && STR(error_text)[0] == '5')
STR(error_text)[0] = '4';
/*
* In any case, enforce consistency between the SMTP code and DSN code.
* SMTP has the higher precedence since it came here first.
*/
STR(error_text)[4] = STR(error_text)[0];
/*
* Log what is happening. When the sysadmin discards policy violation
* postmaster notices, this may be the only trace left that service was
* rejected. Print the request, client name/address, and response.
*/
log_whatsup(state, whatsup, STR(error_text));
return (warn_if_reject ? 0 : SMTPD_CHECK_REJECT);
}
/* defer_if - prepare to change our mind */
static int defer_if(SMTPD_DEFER *defer, int error_class,
int code, const char *dsn,
const char *fmt,...)
{
va_list ap;
/*
* Keep the first reason for this type of deferral, to minimize
* confusion.
*/
if (defer->active == 0) {
defer->active = 1;
defer->class = error_class;
defer->code = code;
if (defer->dsn == 0)
defer->dsn = vstring_alloc(10);
vstring_strcpy(defer->dsn, dsn);
if (defer->reason == 0)
defer->reason = vstring_alloc(10);
va_start(ap, fmt);
vstring_vsprintf(defer->reason, fmt, ap);
va_end(ap);
}
return (SMTPD_CHECK_DUNNO);
}
/* reject_dict_retry - reject with temporary failure if dict lookup fails */
static NORETURN reject_dict_retry(SMTPD_STATE *state, const char *reply_name)
{
longjmp(smtpd_check_buf, smtpd_check_reject(state, MAIL_ERROR_DATA,
451, "4.3.0",
"<%s>: Temporary lookup failure",
reply_name));
}
/* reject_server_error - reject with temporary failure after non-dict error */
static NORETURN reject_server_error(SMTPD_STATE *state)
{
longjmp(smtpd_check_buf, smtpd_check_reject(state, MAIL_ERROR_SOFTWARE,
451, "4.3.5",
"Server configuration error"));
}
/* check_mail_addr_find - reject with temporary failure if dict lookup fails */
static const char *check_mail_addr_find(SMTPD_STATE *state,
const char *reply_name,
MAPS *maps, const char *key,
char **ext)
{
const char *result;
if ((result = mail_addr_find(maps, key, ext)) != 0 || maps->error == 0)
return (result);
if (maps->error == DICT_ERR_RETRY)
/* Warning is already logged. */
reject_dict_retry(state, reply_name);
else
reject_server_error(state);
}
/* reject_unknown_reverse_name - fail if reverse client hostname is unknown */
static int reject_unknown_reverse_name(SMTPD_STATE *state)
{
const char *myname = "reject_unknown_reverse_name";
if (msg_verbose)
msg_info("%s: %s", myname, state->reverse_name);
if (state->reverse_name_status != SMTPD_PEER_CODE_OK)
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
state->reverse_name_status == SMTPD_PEER_CODE_PERM ?
var_unk_client_code : 450, "4.7.1",
"Client host rejected: cannot find your reverse hostname, [%s]",
state->addr));
return (SMTPD_CHECK_DUNNO);
}
/* reject_unknown_client - fail if client hostname is unknown */
static int reject_unknown_client(SMTPD_STATE *state)
{
const char *myname = "reject_unknown_client";
if (msg_verbose)
msg_info("%s: %s %s", myname, state->name, state->addr);
/* RFC 7372: Email Authentication Status Codes. */
if (state->name_status != SMTPD_PEER_CODE_OK)
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
state->name_status >= SMTPD_PEER_CODE_PERM ?
var_unk_client_code : 450, "4.7.25",
"Client host rejected: cannot find your hostname, [%s]",
state->addr));
return (SMTPD_CHECK_DUNNO);
}
/* reject_plaintext_session - fail if session is not encrypted */
static int reject_plaintext_session(SMTPD_STATE *state)
{
const char *myname = "reject_plaintext_session";
if (msg_verbose)
msg_info("%s: %s %s", myname, state->name, state->addr);
#ifdef USE_TLS
if (state->tls_context == 0)
#endif
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_plaintext_code, "4.7.1",
"Session encryption is required"));
return (SMTPD_CHECK_DUNNO);
}
/* permit_inet_interfaces - succeed if client my own address */
static int permit_inet_interfaces(SMTPD_STATE *state)
{
const char *myname = "permit_inet_interfaces";
if (msg_verbose)
msg_info("%s: %s %s", myname, state->name, state->addr);
if (own_inet_addr((struct sockaddr *) &(state->sockaddr)))
/* Permit logging in generic_checks() only. */
return (SMTPD_CHECK_OK);
return (SMTPD_CHECK_DUNNO);
}
/* permit_mynetworks - succeed if client is in a trusted network */
static int permit_mynetworks(SMTPD_STATE *state)
{
const char *myname = "permit_mynetworks";
if (msg_verbose)
msg_info("%s: %s %s", myname, state->name, state->addr);
if (namadr_list_match(mynetworks_curr, state->name, state->addr)) {
if (warn_compat_break_mynetworks_style
&& !namadr_list_match(mynetworks_new, state->name, state->addr))
msg_info("using backwards-compatible default setting "
VAR_MYNETWORKS_STYLE "=%s to permit request from "
"client \"%s\"", var_mynetworks_style, state->namaddr);
/* Permit logging in generic_checks() only. */
return (SMTPD_CHECK_OK);
} else if (mynetworks_curr->error == 0)
return (SMTPD_CHECK_DUNNO);
else
return (mynetworks_curr->error);
}
/* dup_if_truncate - save hostname and truncate if it ends in dot */
static char *dup_if_truncate(char *name)
{
ssize_t len;
char *result;
/*
* Truncate hostnames ending in dot but not dot-dot.
*
* XXX This should not be distributed all over the code. Problem is,
* addresses can enter the system via multiple paths: networks, local
* forward/alias/include files, even as the result of address rewriting.
*/
if ((len = strlen(name)) > 1
&& name[len - 1] == '.'
&& name[len - 2] != '.') {
result = mystrndup(name, len - 1);
} else
result = name;
return (result);
}
/* reject_invalid_hostaddr - fail if host address is incorrect */
static int reject_invalid_hostaddr(SMTPD_STATE *state, char *addr,
char *reply_name, char *reply_class)
{
const char *myname = "reject_invalid_hostaddr";
ssize_t len;
char *test_addr;
int stat;
if (msg_verbose)
msg_info("%s: %s", myname, addr);
if (addr[0] == '[' && (len = strlen(addr)) > 2 && addr[len - 1] == ']') {
test_addr = mystrndup(addr + 1, len - 2);
} else
test_addr = addr;
/*
* Validate the address.
*/
if (!valid_mailhost_addr(test_addr, DONT_GRIPE))
stat = smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_bad_name_code, "5.5.2",
"<%s>: %s rejected: invalid ip address",
reply_name, reply_class);
else
stat = SMTPD_CHECK_DUNNO;
/*
* Cleanup.
*/
if (test_addr != addr)
myfree(test_addr);
return (stat);
}
/* reject_invalid_hostname - fail if host/domain syntax is incorrect */
static int reject_invalid_hostname(SMTPD_STATE *state, char *name,
char *reply_name, char *reply_class)
{
const char *myname = "reject_invalid_hostname";
char *test_name;
int stat;
if (msg_verbose)
msg_info("%s: %s", myname, name);
/*
* Truncate hostnames ending in dot but not dot-dot.
*/
test_name = dup_if_truncate(name);
/*
* Validate the HELO/EHLO hostname. Fix 20140706: EAI not allowed here.
*/
if (!valid_hostname(test_name, DONT_GRIPE)
&& !valid_hostaddr(test_name, DONT_GRIPE)) /* XXX back compat */
stat = smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_bad_name_code, "5.5.2",
"<%s>: %s rejected: Invalid name",
reply_name, reply_class);
else
stat = SMTPD_CHECK_DUNNO;
/*
* Cleanup.
*/
if (test_name != name)
myfree(test_name);
return (stat);
}
/* reject_non_fqdn_hostname - fail if host name is not in fqdn form */
static int reject_non_fqdn_hostname(SMTPD_STATE *state, char *name,
char *reply_name, char *reply_class)
{
const char *myname = "reject_non_fqdn_hostname";
char *test_name;
int stat;
if (msg_verbose)
msg_info("%s: %s", myname, name);
/*
* Truncate hostnames ending in dot but not dot-dot.
*/
test_name = dup_if_truncate(name);
/*
* Validate the hostname. For backwards compatibility, permit non-ASCII
* names only when the client requested SMTPUTF8 support.
*/
if (valid_utf8_hostname(state->flags & SMTPD_FLAG_SMTPUTF8,
test_name, DONT_GRIPE) == 0 || strchr(test_name, '.') == 0)
stat = smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_non_fqdn_code, "5.5.2",
"<%s>: %s rejected: need fully-qualified hostname",
reply_name, reply_class);
else
stat = SMTPD_CHECK_DUNNO;
/*
* Cleanup.
*/
if (test_name != name)
myfree(test_name);
return (stat);
}
/* reject_unknown_hostname - fail if name has no A, AAAA or MX record */
static int reject_unknown_hostname(SMTPD_STATE *state, char *name,
char *reply_name, char *reply_class)
{
const char *myname = "reject_unknown_hostname";
int dns_status;
DNS_RR *dummy;
if (msg_verbose)
msg_info("%s: %s", myname, name);
#ifdef T_AAAA
#define RR_ADDR_TYPES T_A, T_AAAA
#else
#define RR_ADDR_TYPES T_A
#endif
dns_status = dns_lookup_l(name, 0, &dummy, (VSTRING *) 0,
(VSTRING *) 0, DNS_REQ_FLAG_STOP_OK,
RR_ADDR_TYPES, T_MX, 0);
if (dummy)
dns_rr_free(dummy);
/* Allow MTA names to have nullMX records. */
if (dns_status != DNS_OK && dns_status != DNS_NULLMX) {
if (dns_status == DNS_POLICY) {
msg_warn("%s: address or MX lookup error: %s",
name, "DNS reply filter drops all results");
return (SMTPD_CHECK_DUNNO);
}
if (dns_status != DNS_RETRY)
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_unk_name_code, "4.7.1",
"<%s>: %s rejected: %s",
reply_name, reply_class,
dns_status == DNS_INVAL ?
"Malformed DNS server reply" :
"Host not found"));
else
return (DEFER_IF_PERMIT2(unk_name_tf_act, state, MAIL_ERROR_POLICY,
450, "4.7.1",
"<%s>: %s rejected: Host not found",
reply_name, reply_class));
}
return (SMTPD_CHECK_DUNNO);
}
/* reject_unknown_mailhost - fail if name has no A, AAAA or MX record */
static int reject_unknown_mailhost(SMTPD_STATE *state, const char *name,
const char *reply_name, const char *reply_class)
{
const char *myname = "reject_unknown_mailhost";
int dns_status;
DNS_RR *dummy;
const char *aname;
if (msg_verbose)
msg_info("%s: %s", myname, name);
/*
* Fix 20140924: convert domain to ASCII.
*/
#ifndef NO_EAI
if (!allascii(name) && (aname = midna_domain_to_ascii(name)) != 0) {
if (msg_verbose)
msg_info("%s asciified to %s", name, aname);
name = aname;
}
#endif
#define MAILHOST_LOOKUP_FLAGS \
(DNS_REQ_FLAG_STOP_OK | DNS_REQ_FLAG_STOP_INVAL | \
DNS_REQ_FLAG_STOP_NULLMX | DNS_REQ_FLAG_STOP_MX_POLICY)
dns_status = dns_lookup_l(name, 0, &dummy, (VSTRING *) 0,
(VSTRING *) 0, MAILHOST_LOOKUP_FLAGS,
T_MX, RR_ADDR_TYPES, 0);
if (dummy)
dns_rr_free(dummy);
if (dns_status != DNS_OK) { /* incl. DNS_INVAL */
if (dns_status == DNS_POLICY) {
msg_warn("%s: MX or address lookup error: %s",
name, "DNS reply filter drops all results");
return (SMTPD_CHECK_DUNNO);
}
if (dns_status == DNS_NULLMX)
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
550 : 556,
strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
"4.7.27" : "4.1.10",
"<%s>: %s rejected: Domain %s "
"does not accept mail (nullMX)",
reply_name, reply_class, name));
if (dns_status != DNS_RETRY)
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_unk_addr_code,
strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
"4.1.8" : "4.1.2",
"<%s>: %s rejected: %s",
reply_name, reply_class,
dns_status == DNS_INVAL ?
"Malformed DNS server reply" :
"Domain not found"));
else
return (DEFER_IF_PERMIT2(unk_addr_tf_act, state, MAIL_ERROR_POLICY,
450, strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
"4.1.8" : "4.1.2",
"<%s>: %s rejected: Domain not found",
reply_name, reply_class));
}
return (SMTPD_CHECK_DUNNO);
}
static int permit_auth_destination(SMTPD_STATE *state, char *recipient);
/* permit_tls_clientcerts - OK/DUNNO for message relaying, or set dict_errno */
static int permit_tls_clientcerts(SMTPD_STATE *state, int permit_all_certs)
{
#ifdef USE_TLS
const char *found = 0;
if (!state->tls_context)
return SMTPD_CHECK_DUNNO;
if (TLS_CERT_IS_TRUSTED(state->tls_context) && permit_all_certs) {
if (msg_verbose)
msg_info("Relaying allowed for all verified client certificates");
/* Permit logging in generic_checks() only. */
return (SMTPD_CHECK_OK);
}
/*
* When directly checking the fingerprint, it is OK if the issuing CA is
* not trusted.
*/
if (TLS_CERT_IS_PRESENT(state->tls_context)) {
int i;
char *prints[2];
prints[0] = state->tls_context->peer_cert_fprint;
prints[1] = state->tls_context->peer_pkey_fprint;
/* After lookup error, leave relay_ccerts->error at non-zero value. */
for (i = 0; i < 2; ++i) {
found = maps_find(relay_ccerts, prints[i], DICT_FLAG_NONE);
if (found != 0) {
if (msg_verbose)
msg_info("Relaying allowed for certified client: %s", found);
/* Permit logging in generic_checks() only. */
return (SMTPD_CHECK_OK);
} else if (relay_ccerts->error != 0) {
msg_warn("relay_clientcerts: lookup error for fingerprint '%s', "
"pkey fingerprint %s", prints[0], prints[1]);
return (relay_ccerts->error);
}
}
if (msg_verbose)
msg_info("relay_clientcerts: No match for fingerprint '%s', "
"pkey fingerprint %s", prints[0], prints[1]);
}
#endif
return (SMTPD_CHECK_DUNNO);
}
/* check_relay_domains - OK/FAIL for message relaying */
static int check_relay_domains(SMTPD_STATE *state, char *recipient,
char *reply_name, char *reply_class)
{
const char *myname = "check_relay_domains";
#if 1
static int once;
if (once == 0) {
once = 1;
msg_warn("support for restriction \"%s\" will be removed from %s; "
"use \"%s\" instead",
CHECK_RELAY_DOMAINS, var_mail_name, REJECT_UNAUTH_DEST);
}
#endif
if (msg_verbose)
msg_info("%s: %s", myname, recipient);
/*
* Permit if the client matches the relay_domains list.
*/
if (domain_list_match(relay_domains, state->name)) {
if (warn_compat_break_relay_domains)
msg_info("using backwards-compatible default setting "
VAR_RELAY_DOMAINS "=$mydestination to permit "
"request from client \"%s\"", state->name);
return (SMTPD_CHECK_OK);
}
/*
* Permit authorized destinations.
*/
if (permit_auth_destination(state, recipient) == SMTPD_CHECK_OK)
return (SMTPD_CHECK_OK);
/*
* Deny relaying between sites that both are not in relay_domains.
*/
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_relay_code, "5.7.1",
"<%s>: %s rejected: Relay access denied",
reply_name, reply_class));
}
/* permit_auth_destination - OK for message relaying */
static int permit_auth_destination(SMTPD_STATE *state, char *recipient)
{
const char *myname = "permit_auth_destination";
const RESOLVE_REPLY *reply;
const char *domain;
if (msg_verbose)
msg_info("%s: %s", myname, recipient);
/*
* Resolve the address.
*/
reply = smtpd_resolve_addr(state->sender, recipient);
if (reply->flags & RESOLVE_FLAG_FAIL)
reject_dict_retry(state, recipient);
/*
* Handle special case that is not supposed to happen.
*/
if ((domain = strrchr(CONST_STR(reply->recipient), '@')) == 0)
return (SMTPD_CHECK_OK);
domain += 1;
/*
* Skip source-routed non-local or virtual mail (uncertain destination).
*/
if (var_allow_untrust_route == 0 && (reply->flags & RESOLVE_FLAG_ROUTED))
return (SMTPD_CHECK_DUNNO);
/*
* Permit final delivery: the destination matches mydestination,
* virtual_alias_domains, or virtual_mailbox_domains.
*/
if (reply->flags & RESOLVE_CLASS_FINAL)
return (SMTPD_CHECK_OK);
/*
* Permit if the destination matches the relay_domains list.
*/
if (reply->flags & RESOLVE_CLASS_RELAY) {
if (warn_compat_break_relay_domains)
msg_info("using backwards-compatible default setting "
VAR_RELAY_DOMAINS "=$mydestination to accept mail "
"for domain \"%s\"", domain);
return (SMTPD_CHECK_OK);
}
/*
* Skip when not matched
*/
return (SMTPD_CHECK_DUNNO);
}
/* reject_unauth_destination - FAIL for message relaying */
static int reject_unauth_destination(SMTPD_STATE *state, char *recipient,
int reply_code, const char *reply_dsn)
{
const char *myname = "reject_unauth_destination";
if (msg_verbose)
msg_info("%s: %s", myname, recipient);
/*
* Skip authorized destination.
*/
if (permit_auth_destination(state, recipient) == SMTPD_CHECK_OK)
return (SMTPD_CHECK_DUNNO);
/*
* Reject relaying to sites that are not listed in relay_domains.
*/
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
reply_code, reply_dsn,
"<%s>: Relay access denied",
recipient));
}
/* reject_unauth_pipelining - reject improper use of SMTP command pipelining */
static int reject_unauth_pipelining(SMTPD_STATE *state,
const char *reply_name, const char *reply_class)
{
const char *myname = "reject_unauth_pipelining";
if (msg_verbose)
msg_info("%s: %s", myname, state->where);
if (state->flags & SMTPD_FLAG_ILL_PIPELINING)
return (smtpd_check_reject(state, MAIL_ERROR_PROTOCOL,
503, "5.5.0",
"<%s>: %s rejected: Improper use of SMTP command pipelining",
reply_name, reply_class));
return (SMTPD_CHECK_DUNNO);
}
/* all_auth_mx_addr - match host addresses against permit_mx_backup_networks */
static int all_auth_mx_addr(SMTPD_STATE *state, char *host,
const char *reply_name, const char *reply_class)
{
const char *myname = "all_auth_mx_addr";
MAI_HOSTADDR_STR hostaddr;
DNS_RR *rr;
DNS_RR *addr_list;
int dns_status;
if (msg_verbose)
msg_info("%s: host %s", myname, host);
/*
* If we can't lookup the host, defer.
*/
#define NOPE 0
#define YUP 1
/*
* Verify that all host addresses are within permit_mx_backup_networks.
*/
dns_status = dns_lookup_v(host, 0, &addr_list, (VSTRING *) 0, (VSTRING *) 0,
DNS_REQ_FLAG_NONE, inet_proto_info()->dns_atype_list);
/* DNS_NULLMX is not applicable here. */
if (dns_status != DNS_OK) { /* incl. DNS_INVAL */
DEFER_IF_REJECT4(state, MAIL_ERROR_POLICY,
450, "4.4.4",
"<%s>: %s rejected: Unable to look up host "
"%s as mail exchanger: %s",
reply_name, reply_class, host,
dns_status == DNS_POLICY ?
"DNS reply filter policy" : dns_strerror(h_errno));
return (NOPE);
}
for (rr = addr_list; rr != 0; rr = rr->next) {
if (dns_rr_to_pa(rr, &hostaddr) == 0) {
msg_warn("%s: skipping record type %s for host %s: %m",
myname, dns_strtype(rr->type), host);
continue;
}
if (msg_verbose)
msg_info("%s: checking: %s", myname, hostaddr.buf);
if (!namadr_list_match(perm_mx_networks, host, hostaddr.buf)) {
if (perm_mx_networks->error == 0) {
/*
* Reject: at least one IP address is not listed in
* permit_mx_backup_networks.
*/
if (msg_verbose)
msg_info("%s: address %s for %s does not match %s",
myname, hostaddr.buf, host, VAR_PERM_MX_NETWORKS);
} else {
msg_warn("%s: %s lookup error for address %s for %s",
myname, VAR_PERM_MX_NETWORKS, hostaddr.buf, host);
DEFER_IF_REJECT3(state, MAIL_ERROR_POLICY,
450, "4.4.4",
"<%s>: %s rejected: Unable to verify host %s as mail exchanger",
reply_name, reply_class, host);
}
dns_rr_free(addr_list);
return (NOPE);
}
}
dns_rr_free(addr_list);
return (YUP);
}
/* has_my_addr - see if this host name lists one of my network addresses */
static int has_my_addr(SMTPD_STATE *state, const char *host,
const char *reply_name, const char *reply_class)
{
const char *myname = "has_my_addr";
struct addrinfo *res;
struct addrinfo *res0;
int aierr;
MAI_HOSTADDR_STR hostaddr;
INET_PROTO_INFO *proto_info = inet_proto_info();
if (msg_verbose)
msg_info("%s: host %s", myname, host);
/*
* If we can't lookup the host, defer rather than reject.
*/
#define YUP 1
#define NOPE 0
aierr = hostname_to_sockaddr(host, (char *) 0, 0, &res0);
if (aierr) {
DEFER_IF_REJECT4(state, MAIL_ERROR_POLICY,
450, "4.4.4",
"<%s>: %s rejected: Unable to look up mail exchanger host %s: %s",
reply_name, reply_class, host, MAI_STRERROR(aierr));
return (NOPE);
}
#define HAS_MY_ADDR_RETURN(x) { freeaddrinfo(res0); return (x); }
for (res = res0; res != 0; res = res->ai_next) {
if (strchr((char *) proto_info->sa_family_list, res->ai_family) == 0) {
if (msg_verbose)
msg_info("skipping address family %d for host %s",
res->ai_family, host);
continue;
}
if (msg_verbose) {
SOCKADDR_TO_HOSTADDR(res->ai_addr, res->ai_addrlen,
&hostaddr, (MAI_SERVPORT_STR *) 0, 0);
msg_info("%s: addr %s", myname, hostaddr.buf);
}
if (own_inet_addr(res->ai_addr))
HAS_MY_ADDR_RETURN(YUP);
if (proxy_inet_addr(res->ai_addr))
HAS_MY_ADDR_RETURN(YUP);
}
if (msg_verbose)
msg_info("%s: host %s: no match", myname, host);
HAS_MY_ADDR_RETURN(NOPE);
}
/* i_am_mx - is this machine listed as MX relay */
static int i_am_mx(SMTPD_STATE *state, DNS_RR *mx_list,
const char *reply_name, const char *reply_class)
{
const char *myname = "i_am_mx";
DNS_RR *mx;
/*
* Compare hostnames first. Only if no name match is found, go through
* the trouble of host address lookups.
*/
for (mx = mx_list; mx != 0; mx = mx->next) {
if (msg_verbose)
msg_info("%s: resolve hostname: %s", myname, (char *) mx->data);
if (resolve_local((char *) mx->data) > 0)
return (YUP);
/* if no match or error, match interface addresses instead. */
}
/*
* Argh. Do further DNS lookups and match interface addresses.
*/
for (mx = mx_list; mx != 0; mx = mx->next) {
if (msg_verbose)
msg_info("%s: address lookup: %s", myname, (char *) mx->data);
if (has_my_addr(state, (char *) mx->data, reply_name, reply_class))
return (YUP);
}
/*
* This machine is not listed as MX relay.
*/
if (msg_verbose)
msg_info("%s: I am not listed as MX relay", myname);
return (NOPE);
}
/* permit_mx_primary - authorize primary MX relays */
static int permit_mx_primary(SMTPD_STATE *state, DNS_RR *mx_list,
const char *reply_name, const char *reply_class)
{
const char *myname = "permit_mx_primary";
DNS_RR *mx;
if (msg_verbose)
msg_info("%s", myname);
/*
* See if each best MX host has all IP addresses in
* permit_mx_backup_networks.
*/
for (mx = mx_list; mx != 0; mx = mx->next) {
if (!all_auth_mx_addr(state, (char *) mx->data, reply_name, reply_class))
return (NOPE);
}
/*
* All IP addresses of the best MX hosts are within
* permit_mx_backup_networks.
*/
return (YUP);
}
/* permit_mx_backup - permit use of me as MX backup for recipient domain */
static int permit_mx_backup(SMTPD_STATE *state, const char *recipient,
const char *reply_name, const char *reply_class)
{
const char *myname = "permit_mx_backup";
const RESOLVE_REPLY *reply;
const char *domain;
const char *adomain;
DNS_RR *mx_list;
DNS_RR *middle;
DNS_RR *rest;
int dns_status;
if (msg_verbose)
msg_info("%s: %s", myname, recipient);
/*
* Resolve the address.
*/
reply = smtpd_resolve_addr(state->sender, recipient);
if (reply->flags & RESOLVE_FLAG_FAIL)
reject_dict_retry(state, recipient);
/*
* For backwards compatibility, emulate permit_auth_destination. However,
* old permit_mx_backup implementations allow source routing with local
* address class.
*/
if ((domain = strrchr(CONST_STR(reply->recipient), '@')) == 0)
return (SMTPD_CHECK_OK);
domain += 1;
#if 0
if (reply->flags & RESOLVE_CLASS_LOCAL)
return (SMTPD_CHECK_OK);
#endif
if (var_allow_untrust_route == 0 && (reply->flags & RESOLVE_FLAG_ROUTED))
return (SMTPD_CHECK_DUNNO);
if (reply->flags & RESOLVE_CLASS_FINAL)
return (SMTPD_CHECK_OK);
if (reply->flags & RESOLVE_CLASS_RELAY) {
if (warn_compat_break_relay_domains)
msg_info("using backwards-compatible default setting "
VAR_RELAY_DOMAINS "=$mydestination to accept mail "
"for domain \"%s\"", domain);
return (SMTPD_CHECK_OK);
}
if (msg_verbose)
msg_info("%s: not local: %s", myname, recipient);
/*
* Skip numerical forms that didn't match the local system.
*/
if (domain[0] == '[' && domain[strlen(domain) - 1] == ']')
return (SMTPD_CHECK_DUNNO);
/*
* Fix 20140924: convert domain to ASCII.
*/
#ifndef NO_EAI
if (!allascii(domain) && (adomain = midna_domain_to_ascii(domain)) != 0) {
if (msg_verbose)
msg_info("%s asciified to %s", domain, adomain);
domain = adomain;
}
#endif
/*
* Look up the list of MX host names for this domain. If no MX host is
* found, perhaps it is a CNAME for the local machine. Clients aren't
* supposed to send CNAMEs in SMTP commands, but it happens anyway. If we
* can't look up the destination, play safe and turn reject into defer.
*/
dns_status = dns_lookup(domain, T_MX, 0, &mx_list,
(VSTRING *) 0, (VSTRING *) 0);
#if 0
if (dns_status == DNS_NOTFOUND)
return (has_my_addr(state, domain, reply_name, reply_class) ?
SMTPD_CHECK_OK : SMTPD_CHECK_DUNNO);
#endif
if (dns_status != DNS_OK) { /* incl. DNS_INVAL */
/* We don't special-case DNS_NULLMX. */
if (dns_status == DNS_RETRY || dns_status == DNS_POLICY)
DEFER_IF_REJECT3(state, MAIL_ERROR_POLICY,
450, "4.4.4",
"<%s>: %s rejected: Unable to look up mail "
"exchanger information: %s",
reply_name, reply_class, dns_status == DNS_POLICY ?
"DNS reply filter policy" : dns_strerror(h_errno));
return (SMTPD_CHECK_DUNNO);
}
/*
* Separate MX list into primaries and backups.
*/
mx_list = dns_rr_sort(mx_list, dns_rr_compare_pref_any);
for (middle = mx_list; /* see below */ ; middle = rest) {
rest = middle->next;
if (rest == 0)
break;
if (rest->pref != mx_list->pref) {
middle->next = 0;
break;
}
}
/* postcondition: middle->next = 0, rest may be 0. */
#define PERMIT_MX_BACKUP_RETURN(x) do { \
middle->next = rest; \
dns_rr_free(mx_list); \
return (x); \
} while (0)
/*
* First, see if we match any of the primary MX servers.
*/
if (i_am_mx(state, mx_list, reply_name, reply_class))
PERMIT_MX_BACKUP_RETURN(SMTPD_CHECK_DUNNO);
/*
* Then, see if we match any of the backup MX servers.
*/
if (rest == 0 || !i_am_mx(state, rest, reply_name, reply_class))
PERMIT_MX_BACKUP_RETURN(SMTPD_CHECK_DUNNO);
/*
* Optionally, see if the primary MX hosts are in a restricted list of
* networks.
*/
if (*var_perm_mx_networks
&& !permit_mx_primary(state, mx_list, reply_name, reply_class))
PERMIT_MX_BACKUP_RETURN(SMTPD_CHECK_DUNNO);
/*
* The destination passed all requirements.
*/
PERMIT_MX_BACKUP_RETURN(SMTPD_CHECK_OK);
}
/* reject_non_fqdn_address - fail if address is not in fqdn form */
static int reject_non_fqdn_address(SMTPD_STATE *state, char *addr,
char *reply_name, char *reply_class)
{
const char *myname = "reject_non_fqdn_address";
char *domain;
char *test_dom;
int stat;
if (msg_verbose)
msg_info("%s: %s", myname, addr);
/*
* Locate the domain information.
*/
if ((domain = strrchr(addr, '@')) != 0)
domain++;
else
domain = "";
/*
* Skip forms that we can't handle yet.
*/
if (domain[0] == '[' && domain[strlen(domain) - 1] == ']')
return (SMTPD_CHECK_DUNNO);
/*
* Truncate names ending in dot but not dot-dot.
*/
test_dom = dup_if_truncate(domain);
/*
* Validate the domain. For backwards compatibility, permit non-ASCII
* names only when the client requested SMTPUTF8 support.
*/
if (!*test_dom || !valid_utf8_hostname(state->flags & SMTPD_FLAG_SMTPUTF8,
test_dom, DONT_GRIPE) || !strchr(test_dom, '.'))
stat = smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_non_fqdn_code, "4.5.2",
"<%s>: %s rejected: need fully-qualified address",
reply_name, reply_class);
else
stat = SMTPD_CHECK_DUNNO;
/*
* Cleanup.
*/
if (test_dom != domain)
myfree(test_dom);
return (stat);
}
/* reject_unknown_address - fail if address does not resolve */
static int reject_unknown_address(SMTPD_STATE *state, const char *addr,
const char *reply_name, const char *reply_class)
{
const char *myname = "reject_unknown_address";
const RESOLVE_REPLY *reply;
const char *domain;
if (msg_verbose)
msg_info("%s: %s", myname, addr);
/*
* Resolve the address.
*/
reply = smtpd_resolve_addr(strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
state->recipient : state->sender, addr);
if (reply->flags & RESOLVE_FLAG_FAIL)
reject_dict_retry(state, addr);
/*
* Skip local destinations and non-DNS forms.
*/
if ((domain = strrchr(CONST_STR(reply->recipient), '@')) == 0)
return (SMTPD_CHECK_DUNNO);
domain += 1;
if (reply->flags & RESOLVE_CLASS_FINAL)
return (SMTPD_CHECK_DUNNO);
if (domain[0] == '[' && domain[strlen(domain) - 1] == ']')
return (SMTPD_CHECK_DUNNO);
/*
* Look up the name in the DNS.
*/
return (reject_unknown_mailhost(state, domain, reply_name, reply_class));
}
/* reject_unverified_address - fail if address bounces */
static int reject_unverified_address(SMTPD_STATE *state, const char *addr,
const char *reply_name, const char *reply_class,
int unv_addr_dcode, int unv_addr_rcode,
int unv_addr_tf_act,
const char *alt_reply)
{
const char *myname = "reject_unverified_address";
VSTRING *why = vstring_alloc(10);
int rqst_status = SMTPD_CHECK_DUNNO;
int rcpt_status;
int verify_status;
int count;
int reject_code = 0;
if (msg_verbose)
msg_info("%s: %s", myname, addr);
/*
* Verify the address. Don't waste too much of their or our time.
*/
for (count = 0; /* see below */ ; /* see below */ ) {
verify_status = verify_clnt_query(addr, &rcpt_status, why);
if (verify_status != VRFY_STAT_OK || rcpt_status != DEL_RCPT_STAT_TODO)
break;
if (++count >= var_verify_poll_count)
break;
sleep(var_verify_poll_delay);
}
if (verify_status != VRFY_STAT_OK) {
msg_warn("%s service failure", var_verify_service);
rqst_status =
DEFER_IF_PERMIT2(unv_addr_tf_act, state, MAIL_ERROR_POLICY,
450, strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
SND_DSN : "4.1.1",
"<%s>: %s rejected: address verification problem",
reply_name, reply_class);
} else {
switch (rcpt_status) {
default:
msg_warn("unknown address verification status %d", rcpt_status);
break;
case DEL_RCPT_STAT_TODO:
case DEL_RCPT_STAT_DEFER:
reject_code = unv_addr_dcode;
break;
case DEL_RCPT_STAT_OK:
break;
case DEL_RCPT_STAT_BOUNCE:
reject_code = unv_addr_rcode;
break;
}
if (reject_code >= 400 && *alt_reply)
vstring_strcpy(why, alt_reply);
switch (reject_code / 100) {
case 2:
break;
case 4:
rqst_status =
DEFER_IF_PERMIT3(unv_addr_tf_act, state, MAIL_ERROR_POLICY,
reject_code,
strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
SND_DSN : "4.1.1",
"<%s>: %s rejected: unverified address: %.250s",
reply_name, reply_class, STR(why));
break;
default:
if (reject_code != 0)
rqst_status =
smtpd_check_reject(state, MAIL_ERROR_POLICY,
reject_code,
strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
SND_DSN : "4.1.1",
"<%s>: %s rejected: undeliverable address: %s",
reply_name, reply_class, STR(why));
break;
}
}
vstring_free(why);
return (rqst_status);
}
/* can_delegate_action - can we delegate this to the cleanup server */
#ifndef TEST
static int not_in_client_helo(SMTPD_STATE *, const char *, const char *, const char *);
static int can_delegate_action(SMTPD_STATE *state, const char *table,
const char *action, const char *reply_class)
{
/*
* If we're not using the cleanup server, then there is no way that we
* can support actions such as FILTER or HOLD that are delegated to the
* cleanup server.
*/
if (USE_SMTPD_PROXY(state)) {
msg_warn("access table %s: with %s specified, action %s is unavailable",
table, VAR_SMTPD_PROXY_FILT, action);
return (0);
}
/*
* ETRN does not receive mail so we can't store queue file records.
*/
if (strcmp(state->where, SMTPD_CMD_ETRN) == 0) {
msg_warn("access table %s: action %s is unavailable in %s",
table, action, VAR_ETRN_CHECKS);
return (0);
}
return (not_in_client_helo(state, table, action, reply_class));
}
/* not_in_client_helo - not in client or helo restriction context */
static int not_in_client_helo(SMTPD_STATE *state, const char *table,
const char *action,
const char *unused_reply_class)
{
/*
* If delay_reject=no, then client and helo restrictions take effect
* immediately, outside any particular mail transaction context. For
* example, rejecting HELO does not affect subsequent mail deliveries.
* Thus, if delay_reject=no, client and helo actions such as FILTER or
* HOLD also should not affect subsequent mail deliveries. Hmm...
*
* XXX If the MAIL FROM command is rejected then we have to reset access map
* side effects such as FILTER.
*/
if (state->sender == 0) {
msg_warn("access table %s: with %s=%s, "
"action %s is always skipped in %s or %s restrictions",
table, VAR_SMTPD_DELAY_REJECT, CONFIG_BOOL_NO,
action, SMTPD_NAME_CLIENT, SMTPD_NAME_HELO);
/* XXX What about ETRN? */
return (0);
}
return (1);
}
#endif
/* check_table_result - translate table lookup result into pass/reject */
static int check_table_result(SMTPD_STATE *state, const char *table,
const char *value, const char *datum,
const char *reply_name,
const char *reply_class,
const char *def_acl)
{
const char *myname = "check_table_result";
int code;
ARGV *restrictions;
jmp_buf savebuf;
int status;
const char *cmd_text;
int cmd_len;
static char def_dsn[] = "5.7.1";
DSN_SPLIT dp;
static VSTRING *buf;
#ifdef DELAY_ACTION
int defer_delay;
#endif
if (buf == 0)
buf = vstring_alloc(10);
/*
* Parse into command and text. Do not change the input.
*/
cmd_text = value + strcspn(value, " \t");
cmd_len = cmd_text - value;
vstring_strncpy(buf, value, cmd_len);
while (*cmd_text && ISSPACE(*cmd_text))
cmd_text++;
if (msg_verbose)
msg_info("%s: %s %s %s", myname, table, value, datum);
#define STREQUAL(x,y,l) (strncasecmp((x), (y), (l)) == 0 && (y)[l] == 0)
/*
* DUNNO means skip this table. Silently ignore optional text.
*/
if (STREQUAL(value, "DUNNO", cmd_len))
return (SMTPD_CHECK_DUNNO);
/*
* REJECT means NO. Use optional text or generate a generic error
* response.
*/
if (STREQUAL(value, "REJECT", cmd_len)) {
dsn_split(&dp, "5.7.1", cmd_text);
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_map_reject_code,
smtpd_dsn_fix(DSN_STATUS(dp.dsn),
reply_class),
"<%s>: %s rejected: %s",
reply_name, reply_class,
*dp.text ? dp.text : "Access denied"));
}
/*
* DEFER means "try again". Use optional text or generate a generic error
* response.
*/
if (STREQUAL(value, "DEFER", cmd_len)) {
dsn_split(&dp, "4.7.1", cmd_text);
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_map_defer_code,
smtpd_dsn_fix(DSN_STATUS(dp.dsn),
reply_class),
"<%s>: %s rejected: %s",
reply_name, reply_class,
*dp.text ? dp.text : "Access denied"));
}
#ifndef SHUT_RDWR
#define SHUT_RDWR 2
#endif
/*
* HANGUP. Text is optional. Drop the connection without sending any
* reply.
*
* Note: this is an unsupported test feature. No attempt is made to maintain
* compatibility between successive versions.
*/
if (STREQUAL(value, "HANGUP", cmd_len)) {
shutdown(vstream_fileno(state->client), SHUT_RDWR);
log_whatsup(state, "hangup", cmd_text);
vstream_longjmp(state->client, SMTP_ERR_QUIET);
}
/*
* INFO. Text is optional.
*/
if (STREQUAL(value, "INFO", cmd_len)) {
log_whatsup(state, "info", cmd_text);
return (SMTPD_CHECK_DUNNO);
}
/*
* WARN. Text is optional.
*/
if (STREQUAL(value, "WARN", cmd_len)) {
log_whatsup(state, "warn", cmd_text);
return (SMTPD_CHECK_DUNNO);
}
/*
* FILTER means deliver to content filter. But we may still change our
* mind, and reject/discard the message for other reasons.
*/
if (STREQUAL(value, "FILTER", cmd_len)) {
#ifndef TEST
if (can_delegate_action(state, table, "FILTER", reply_class) == 0)
return (SMTPD_CHECK_DUNNO);
#endif
if (*cmd_text == 0) {
msg_warn("access table %s entry \"%s\" has FILTER entry without value",
table, datum);
return (SMTPD_CHECK_DUNNO);
} else if (strchr(cmd_text, ':') == 0) {
msg_warn("access table %s entry \"%s\" requires transport:destination",
table, datum);
return (SMTPD_CHECK_DUNNO);
} else {
vstring_sprintf(error_text, "<%s>: %s triggers FILTER %s",
reply_name, reply_class, cmd_text);
log_whatsup(state, "filter", STR(error_text));
#ifndef TEST
UPDATE_STRING(state->saved_filter, cmd_text);
#endif
return (SMTPD_CHECK_DUNNO);
}
}
/*
* HOLD means deliver later. But we may still change our mind, and
* reject/discard the message for other reasons.
*/
if (STREQUAL(value, "HOLD", cmd_len)) {
#ifndef TEST
if (can_delegate_action(state, table, "HOLD", reply_class) == 0
|| (state->saved_flags & CLEANUP_FLAG_HOLD))
return (SMTPD_CHECK_DUNNO);
#endif
vstring_sprintf(error_text, "<%s>: %s %s", reply_name, reply_class,
*cmd_text ? cmd_text : "triggers HOLD action");
log_whatsup(state, "hold", STR(error_text));
#ifndef TEST
state->saved_flags |= CLEANUP_FLAG_HOLD;
#endif
return (SMTPD_CHECK_DUNNO);
}
/*
* DELAY means deliver later. But we may still change our mind, and
* reject/discard the message for other reasons.
*
* This feature is deleted because it has too many problems. 1) It does not
* work on some remote file systems; 2) mail will be delivered anyway
* with "sendmail -q" etc.; 3) while the mail is queued it bogs down the
* deferred queue scan with huge amounts of useless disk I/O operations.
*/
#ifdef DELAY_ACTION
if (STREQUAL(value, "DELAY", cmd_len)) {
#ifndef TEST
if (can_delegate_action(state, table, "DELAY", reply_class) == 0)
return (SMTPD_CHECK_DUNNO);
#endif
if (*cmd_text == 0) {
msg_warn("access table %s entry \"%s\" has DELAY entry without value",
table, datum);
return (SMTPD_CHECK_DUNNO);
}
if (conv_time(cmd_text, &defer_delay, 's') == 0) {
msg_warn("access table %s entry \"%s\" has invalid DELAY argument \"%s\"",
table, datum, cmd_text);
return (SMTPD_CHECK_DUNNO);
}
vstring_sprintf(error_text, "<%s>: %s %s", reply_name, reply_class,
*cmd_text ? cmd_text : "triggers DELAY action");
log_whatsup(state, "delay", STR(error_text));
#ifndef TEST
state->saved_delay = defer_delay;
#endif
return (SMTPD_CHECK_DUNNO);
}
#endif
/*
* DISCARD means silently discard and claim successful delivery.
*/
if (STREQUAL(value, "DISCARD", cmd_len)) {
#ifndef TEST
if (can_delegate_action(state, table, "DISCARD", reply_class) == 0)
return (SMTPD_CHECK_DUNNO);
#endif
vstring_sprintf(error_text, "<%s>: %s %s", reply_name, reply_class,
*cmd_text ? cmd_text : "triggers DISCARD action");
log_whatsup(state, "discard", STR(error_text));
#ifndef TEST
state->saved_flags |= CLEANUP_FLAG_DISCARD;
state->discard = 1;
#endif
return (smtpd_acl_permit(state, STR(buf), reply_class, reply_name,
"from %s", table));
}
/*
* REDIRECT means deliver to designated recipient. But we may still
* change our mind, and reject/discard the message for other reasons.
*/
if (STREQUAL(value, "REDIRECT", cmd_len)) {
#ifndef TEST
if (can_delegate_action(state, table, "REDIRECT", reply_class) == 0)
return (SMTPD_CHECK_DUNNO);
#endif
if (strchr(cmd_text, '@') == 0) {
msg_warn("access table %s entry \"%s\" requires user@domain target",
table, datum);
return (SMTPD_CHECK_DUNNO);
} else {
vstring_sprintf(error_text, "<%s>: %s triggers REDIRECT %s",
reply_name, reply_class, cmd_text);
log_whatsup(state, "redirect", STR(error_text));
#ifndef TEST
UPDATE_STRING(state->saved_redirect, cmd_text);
#endif
return (SMTPD_CHECK_DUNNO);
}
}
/*
* BCC means deliver to designated recipient. But we may still change our
* mind, and reject/discard the message for other reasons.
*/
if (STREQUAL(value, "BCC", cmd_len)) {
#ifndef TEST
if (can_delegate_action(state, table, "BCC", reply_class) == 0)
return (SMTPD_CHECK_DUNNO);
#endif
if (strchr(cmd_text, '@') == 0) {
msg_warn("access table %s entry \"%s\" requires user@domain target",
table, datum);
return (SMTPD_CHECK_DUNNO);
} else {
vstring_sprintf(error_text, "<%s>: %s triggers BCC %s",
reply_name, reply_class, cmd_text);
log_whatsup(state, "bcc", STR(error_text));
#ifndef TEST
if (state->saved_bcc == 0)
state->saved_bcc = argv_alloc(1);
argv_add(state->saved_bcc, cmd_text, (char *) 0);
#endif
return (SMTPD_CHECK_DUNNO);
}
}
/*
* DEFER_IF_PERMIT changes "permit" into "maybe". Use optional text or
* generate a generic error response.
*/
if (STREQUAL(value, DEFER_IF_PERMIT, cmd_len)) {
dsn_split(&dp, "4.7.1", cmd_text);
return (DEFER_IF_PERMIT3(DEFER_IF_PERMIT_ACT, state, MAIL_ERROR_POLICY,
var_map_defer_code,
smtpd_dsn_fix(DSN_STATUS(dp.dsn), reply_class),
"<%s>: %s rejected: %s",
reply_name, reply_class,
*dp.text ? dp.text : "Service unavailable"));
}
/*
* DEFER_IF_REJECT changes "reject" into "maybe". Use optional text or
* generate a generic error response.
*/
if (STREQUAL(value, DEFER_IF_REJECT, cmd_len)) {
dsn_split(&dp, "4.7.1", cmd_text);
DEFER_IF_REJECT3(state, MAIL_ERROR_POLICY,
var_map_defer_code,
smtpd_dsn_fix(DSN_STATUS(dp.dsn), reply_class),
"<%s>: %s rejected: %s",
reply_name, reply_class,
*dp.text ? dp.text : "Service unavailable");
return (SMTPD_CHECK_DUNNO);
}
/*
* PREPEND prepends the specified message header text.
*/
if (STREQUAL(value, "PREPEND", cmd_len)) {
#ifndef TEST
/* XXX what about ETRN. */
if (not_in_client_helo(state, table, "PREPEND", reply_class) == 0)
return (SMTPD_CHECK_DUNNO);
#endif
if (strcmp(state->where, SMTPD_AFTER_DOT) == 0) {
msg_warn("access table %s: action PREPEND must be used before %s",
table, VAR_EOD_CHECKS);
return (SMTPD_CHECK_DUNNO);
}
if (*cmd_text == 0 || is_header(cmd_text) == 0) {
msg_warn("access table %s entry \"%s\" requires header: text",
table, datum);
return (SMTPD_CHECK_DUNNO);
} else {
if (state->prepend == 0)
state->prepend = argv_alloc(1);
argv_add(state->prepend, cmd_text, (char *) 0);
return (SMTPD_CHECK_DUNNO);
}
}
/*
* All-numeric result probably means OK - some out-of-band authentication
* mechanism uses this as time stamp.
*/
if (alldig(value))
return (smtpd_acl_permit(state, STR(buf), reply_class, reply_name,
"from %s", table));
/*
* 4xx or 5xx means NO as well. smtpd_check_reject() will validate the
* response status code.
*
* If the caller specifies an RFC 3463 enhanced status code, put it
* immediately after the SMTP status code as described in RFC 2034.
*/
if (cmd_len == 3 && *cmd_text
&& (value[0] == '4' || value[0] == '5')
&& ISDIGIT(value[1]) && ISDIGIT(value[2])) {
code = atoi(value);
def_dsn[0] = value[0];
dsn_split(&dp, def_dsn, cmd_text);
return (smtpd_check_reject(state, MAIL_ERROR_POLICY,
code,
smtpd_dsn_fix(DSN_STATUS(dp.dsn),
reply_class),
"<%s>: %s rejected: %s",
reply_name, reply_class,
*dp.text ? dp.text : "Access denied"));
}
/*
* OK or RELAY means YES. Ignore trailing text.
*/
if (STREQUAL(value, "OK", cmd_len) || STREQUAL(value, "RELAY", cmd_len))
return (smtpd_acl_permit(state, STR(buf), reply_class, reply_name,
"from %s", table));
/*
* Unfortunately, maps must be declared ahead of time so they can be
* opened before we go to jail. We could insist that the RHS can only
* contain a pre-defined restriction class name, but that would be too
* restrictive. Instead we warn if an access table references any map.
*
* XXX Don't use passwd files or address rewriting maps as access tables.
*/
if (strchr(value, ':') != 0) {
msg_warn("access table %s has entry with lookup table: %s",
table, value);
msg_warn("do not specify lookup tables inside SMTPD access maps");
msg_warn("define a restriction class and specify its name instead.");
reject_server_error(state);
}
/*
* Don't get carried away with recursion.
*/
if (state->recursion > 100) {
msg_warn("access table %s entry %s causes unreasonable recursion",
table, value);
reject_server_error(state);
}
/*
* Recursively evaluate the restrictions given in the right-hand side. In
* the dark ages, an empty right-hand side meant OK. Make some
* discouraging comments.
*
* XXX Jump some hoops to avoid a minute memory leak in case of a file
* configuration error.
*/
#define ADDROF(x) ((char *) &(x))
restrictions = argv_splitq(value, CHARS_COMMA_SP, CHARS_BRACE);
memcpy(ADDROF(savebuf), ADDROF(smtpd_check_buf), sizeof(savebuf));
status = setjmp(smtpd_check_buf);
if (status != 0) {
argv_free(restrictions);
memcpy(ADDROF(smtpd_check_buf), ADDROF(savebuf),
sizeof(smtpd_check_buf));
longjmp(smtpd_check_buf, status);
}
if (restrictions->argc == 0) {
msg_warn("access table %s entry %s has empty value",
table, value);
status = SMTPD_CHECK_OK;
} else {
status = generic_checks(state, restrictions, reply_name,
reply_class, def_acl);
}
argv_free(restrictions);
memcpy(ADDROF(smtpd_check_buf), ADDROF(savebuf), sizeof(smtpd_check_buf));
return (status);
}
/* check_access - table lookup without substring magic */
static int check_access(SMTPD_STATE *state, const char *table, const char *name,
int flags, int *found, const char *reply_name,
const char *reply_class, const char *def_acl)
{
const char *myname = "check_access";
const char *value;
MAPS *maps;
#define CHK_ACCESS_RETURN(x,y) \
{ *found = y; return(x); }
#define FULL 0
#define PARTIAL DICT_FLAG_FIXED
#define FOUND 1
#define MISSED 0
if (msg_verbose)
msg_info("%s: %s", myname, name);
if ((maps = (MAPS *) htable_find(map_command_table, table)) == 0) {
msg_warn("%s: unexpected dictionary: %s", myname, table);
value = "451 4.3.5 Server configuration error";
CHK_ACCESS_RETURN(check_table_result(state, table, value, name,
reply_name, reply_class,
def_acl), FOUND);
}
if ((value = maps_find(maps, name, flags)) != 0)
CHK_ACCESS_RETURN(check_table_result(state, table, value, name,
reply_name, reply_class,
def_acl), FOUND);
if (maps->error != 0) {
/* Warning is already logged. */
value = "451 4.3.5 Server configuration error";
CHK_ACCESS_RETURN(check_table_result(state, table, value, name,
reply_name, reply_class,
def_acl), FOUND);
}
CHK_ACCESS_RETURN(SMTPD_CHECK_DUNNO, MISSED);
}
/* check_domain_access - domainname-based table lookup */
static int check_domain_access(SMTPD_STATE *state, const char *table,
const char *domain, int flags,
int *found, const char *reply_name,
const char *reply_class,
const char *def_acl)
{
const char *myname = "check_domain_access";
const char *name;
const char *next;
const char *value;
MAPS *maps;
int maybe_numerical = 1;
if (msg_verbose)
msg_info("%s: %s", myname, domain);
/*
* Try the name and its parent domains. Including top-level domains.
*
* Helo names can end in ".". The test below avoids lookups of the empty
* key, because Berkeley DB cannot deal with it. [Victor Duchovni, Morgan
* Stanley].
*
* TODO(wietse) move to mail_domain_find library module.
*/
#define CHK_DOMAIN_RETURN(x,y) { *found = y; return(x); }
if ((maps = (MAPS *) htable_find(map_command_table, table)) == 0) {
msg_warn("%s: unexpected dictionary: %s", myname, table);
value = "451 4.3.5 Server configuration error";
CHK_DOMAIN_RETURN(check_table_result(state, table, value,
domain, reply_name, reply_class,
def_acl), FOUND);
}
for (name = domain; *name != 0; name = next) {
if ((value = maps_find(maps, name, flags)) != 0)
CHK_DOMAIN_RETURN(check_table_result(state, table, value,
domain, reply_name, reply_class,
def_acl), FOUND);
if (maps->error != 0) {
/* Warning is already logged. */
value = "451 4.3.5 Server configuration error";
CHK_DOMAIN_RETURN(check_table_result(state, table, value,
domain, reply_name, reply_class,
def_acl), FOUND);
}
/* Don't apply subdomain magic to numerical hostnames. */
if (maybe_numerical
&& (maybe_numerical = valid_hostaddr(domain, DONT_GRIPE)) != 0)
break;
if ((next = strchr(name + 1, '.')) == 0)
break;
if (access_parent_style == MATCH_FLAG_PARENT)
next += 1;
flags = PARTIAL;
}
CHK_DOMAIN_RETURN(SMTPD_CHECK_DUNNO, MISSED);
}
/* check_addr_access - address-based table lookup */
static int check_addr_access(SMTPD_STATE *state, const char *table,
const char *address, int flags,
int *found, const char *reply_name,
const char *reply_class,
const char *def_acl)
{
const char *myname = "check_addr_access";
char *addr;
const char *value;
MAPS *maps;
int delim;
if (msg_verbose)
msg_info("%s: %s", myname, address);
/*
* Try the address and its parent networks.
*
* TODO(wietse) move to mail_ipaddr_find library module.
*/
#define CHK_ADDR_RETURN(x,y) { *found = y; return(x); }
addr = STR(vstring_strcpy(error_text, address));
#ifdef HAS_IPV6
if (strchr(addr, ':') != 0)
delim = ':';
else
#endif
delim = '.';
if ((maps = (MAPS *) htable_find(map_command_table, table)) == 0) {
msg_warn("%s: unexpected dictionary: %s", myname, table);
value = "451 4.3.5 Server configuration error";
CHK_ADDR_RETURN(check_table_result(state, table, value, address,
reply_name, reply_class,
def_acl), FOUND);
}
do {
if ((value = maps_find(maps, addr, flags)) != 0)
CHK_ADDR_RETURN(check_table_result(state, table, value, address,
reply_name, reply_class,
def_acl), FOUND);
if (maps->error != 0) {
/* Warning is already logged. */
value = "451 4.3.5 Server configuration error";
CHK_ADDR_RETURN(check_table_result(state, table, value, address,
reply_name, reply_class,
def_acl), FOUND);
}
flags = PARTIAL;
} while (split_at_right(addr, delim));
CHK_ADDR_RETURN(SMTPD_CHECK_DUNNO, MISSED);
}
/* check_namadr_access - OK/FAIL based on host name/address lookup */
static int check_namadr_access(SMTPD_STATE *state, const char *table,
const char *name, const char *addr,
int flags, int *found,
const char *reply_name,
const char *reply_class,
const char *def_acl)
{
const char *myname = "check_namadr_access";
int status;
if (msg_verbose)
msg_info("%s: name %s addr %s", myname, name, addr);
/*
* Look up the host name, or parent domains thereof. XXX A domain
* wildcard may pre-empt a more specific address table entry.
*/
if ((status = check_domain_access(state, table, name, flags,
found, reply_name, reply_class,
def_acl)) != 0 || *found)
return (status);
/*
* Look up the network address, or parent networks thereof.
*/
if ((status = check_addr_access(state, table, addr, flags,
found, reply_name, reply_class,
def_acl)) != 0 || *found)
return (status);
/*
* Undecided when the host was not found.
*/
return (SMTPD_CHECK_DUNNO);
}
/* check_server_access - access control by server host name or address */
static int check_server_access(SMTPD_STATE *state, const char *table,
const char *name,
int type,
const char *reply_name,
const char *reply_class,
const char *def_acl)
{
const char *myname = "check_server_access";
const char *domain;
const char *adomain;
int dns_status;
DNS_RR *server_list;
DNS_RR *server;
int found = 0;
MAI_HOSTADDR_STR addr_string;
int aierr;
struct addrinfo *res0;
struct addrinfo *res;
int status;
INET_PROTO_INFO *proto_info;
/*
* Sanity check.
*/
if (type != T_MX && type != T_NS && type != T_A
#ifdef HAS_IPV6
&& type != T_AAAA
#endif
)
msg_panic("%s: unexpected resource type \"%s\" in request",
myname, dns_strtype(type));
if (msg_verbose)
msg_info("%s: %s %s", myname, dns_strtype(type), name);
/*
* Skip over local-part.
*/
if ((domain = strrchr(name, '@')) != 0)
domain += 1;
else
domain = name;
/*
* Treat an address literal as its own MX server, just like we treat a
* name without MX record as its own MX server. There is, however, no
* applicable NS server equivalent.
*/
if (*domain == '[') {
char *saved_addr;
const char *bare_addr;
ssize_t len;
if (type != T_A && type != T_MX)
return (SMTPD_CHECK_DUNNO);
len = strlen(domain);
if (domain[len - 1] != ']')
return (SMTPD_CHECK_DUNNO);
/* Memory leak alert: no early returns after this point. */
saved_addr = mystrndup(domain + 1, len - 2);
if ((bare_addr = valid_mailhost_addr(saved_addr, DONT_GRIPE)) == 0)
status = SMTPD_CHECK_DUNNO;
else
status = check_addr_access(state, table, bare_addr, FULL,
&found, reply_name, reply_class,
def_acl);
myfree(saved_addr);
return (status);
}
/*
* Fix 20140924: convert domain to ASCII.
*/
#ifndef NO_EAI
if (!allascii(domain) && (adomain = midna_domain_to_ascii(domain)) != 0) {
if (msg_verbose)
msg_info("%s asciified to %s", domain, adomain);
domain = adomain;
}
#endif
/*
* If the request is type A or AAAA, fabricate an MX record that points
* to the domain name itself, and skip name-based access control.
*
* If the domain name does not exist then we apply no restriction.
*
* If the domain name exists but no MX record exists, fabricate an MX record
* that points to the domain name itself.
*
* If the domain name exists but no NS record exists, look up parent domain
* NS records.
*
* XXX 20150707 Work around broken DNS servers that reply with NXDOMAIN
* instead of "no data".
*/
if (type == T_A
#ifdef HAS_IPV6
|| type == T_AAAA
#endif
) {
server_list = dns_rr_create(domain, domain, T_MX, C_IN, 0, 0,
domain, strlen(domain) + 1);
} else {
dns_status = dns_lookup(domain, type, 0, &server_list,
(VSTRING *) 0, (VSTRING *) 0);
if (dns_status == DNS_NULLMX)
return (SMTPD_CHECK_DUNNO);
if (dns_status == DNS_NOTFOUND /* Not: h_errno == NO_DATA */ ) {
if (type == T_MX) {
server_list = dns_rr_create(domain, domain, type, C_IN, 0, 0,
domain, strlen(domain) + 1);
dns_status = DNS_OK;
} else if (type == T_NS /* && h_errno == NO_DATA */ ) {
while ((domain = strchr(domain, '.')) != 0 && domain[1]) {
domain += 1;
dns_status = dns_lookup(domain, type, 0, &server_list,
(VSTRING *) 0, (VSTRING *) 0);
if (dns_status != DNS_NOTFOUND /* || h_errno != NO_DATA */ )
break;
}
}
}
if (dns_status != DNS_OK) {
msg_warn("Unable to look up %s host for %s: %s", dns_strtype(type),
domain && domain[1] ? domain : name, dns_status == DNS_POLICY ?
"DNS reply filter policy" : dns_strerror(h_errno));
return (SMTPD_CHECK_DUNNO);
}
}
/*
* No bare returns after this point or we have a memory leak.
*/
#define CHECK_SERVER_RETURN(x) { dns_rr_free(server_list); return(x); }
/*
* Check the hostnames first, then the addresses.
*/
proto_info = inet_proto_info();
for (server = server_list; server != 0; server = server->next) {
if (msg_verbose)
msg_info("%s: %s hostname check: %s",
myname, dns_strtype(type), (char *) server->data);
if (valid_hostaddr((char *) server->data, DONT_GRIPE)) {
if ((status = check_addr_access(state, table, (char *) server->data,
FULL, &found, reply_name, reply_class,
def_acl)) != 0 || found)
CHECK_SERVER_RETURN(status);
continue;
}
if (type != T_A && type != T_AAAA
&& ((status = check_domain_access(state, table, (char *) server->data,
FULL, &found, reply_name, reply_class,
def_acl)) != 0 || found))
CHECK_SERVER_RETURN(status);
if ((aierr = hostname_to_sockaddr((char *) server->data,
(char *) 0, 0, &res0)) != 0) {
if (type != T_A && type != T_AAAA)
msg_warn("Unable to look up %s host %s for %s %s: %s",
dns_strtype(type), (char *) server->data,
reply_class, reply_name, MAI_STRERROR(aierr));
continue;
}
/* Now we must also free the addrinfo result. */
if (msg_verbose)
msg_info("%s: %s host address check: %s",
myname, dns_strtype(type), (char *) server->data);
for (res = res0; res != 0; res = res->ai_next) {
if (strchr((char *) proto_info->sa_family_list, res->ai_family) == 0) {
if (msg_verbose)
msg_info("skipping address family %d for host %s",
res->ai_family, server->data);
continue;
}
SOCKADDR_TO_HOSTADDR(res->ai_addr, res->ai_addrlen,
&addr_string, (MAI_SERVPORT_STR *) 0, 0);
status = check_addr_access(state, table, addr_string.buf, FULL,
&found, reply_name, reply_class,
def_acl);
if (status != 0 || found) {
freeaddrinfo(res0); /* 200412 */
CHECK_SERVER_RETURN(status);
}
}
freeaddrinfo(res0); /* 200412 */
}
CHECK_SERVER_RETURN(SMTPD_CHECK_DUNNO);
}
/* check_ccert_access - access for TLS clients by certificate fingerprint */
static int check_ccert_access(SMTPD_STATE *state, const char *table,
const char *def_acl)
{
int result = SMTPD_CHECK_DUNNO;
#ifdef USE_TLS
const char *myname = "check_ccert_access";
int found;
/*
* When directly checking the fingerprint, it is OK if the issuing CA is
* not trusted.
*/
if (TLS_CERT_IS_PRESENT(state->tls_context)) {
int i;
char *prints[2];
prints[0] = state->tls_context->peer_cert_fprint;
prints[1] = state->tls_context->peer_pkey_fprint;
for (i = 0; i < 2; ++i) {
if (msg_verbose)
msg_info("%s: %s", myname, prints[i]);
/*
* Regexp tables don't make sense for certificate fingerprints.
* That may be so, but we can't ignore the entire
* check_ccert_access request without logging a warning.
*
* Log the peer CommonName when access is denied. Non-printable
* characters will be neutered by smtpd_check_reject(). The SMTP
* client name and address are always syslogged as part of a
* "reject" event.
*/
result = check_access(state, table, prints[i],
DICT_FLAG_NONE, &found,
state->tls_context->peer_CN,
SMTPD_NAME_CCERT, def_acl);
if (result != SMTPD_CHECK_DUNNO)
break;
}
}
#endif
return (result);
}
/* check_sasl_access - access by SASL user name */
#ifdef USE_SASL_AUTH
static int check_sasl_access(SMTPD_STATE *state, const char *table,
const char *def_acl)
{
int result;
int unused_found;
char *sane_username = printable(mystrdup(state->sasl_username), '_');
result = check_access(state, table, state->sasl_username,
DICT_FLAG_NONE, &unused_found, sane_username,
SMTPD_NAME_SASL_USER, def_acl);
myfree(sane_username);
return (result);
}
#endif
/* check_mail_access - OK/FAIL based on mail address lookup */
static int check_mail_access(SMTPD_STATE *state, const char *table,
const char *addr, int *found,
const char *reply_name,
const char *reply_class,
const char *def_acl)
{
const char *myname = "check_mail_access";
const RESOLVE_REPLY *reply;
const char *value;
int status;
MAPS *maps;
if (msg_verbose)
msg_info("%s: %s", myname, addr);
/*
* Resolve the address.
*/
reply = smtpd_resolve_addr(strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
state->recipient : state->sender, addr);
if (reply->flags & RESOLVE_FLAG_FAIL)
reject_dict_retry(state, addr);
/*
* Garbage in, garbage out. Every address from rewrite_clnt_internal()
* and from resolve_clnt_query() must be fully qualified.
*/
if (strrchr(CONST_STR(reply->recipient), '@') == 0) {
msg_warn("%s: no @domain in address: %s", myname,
CONST_STR(reply->recipient));
return (0);
}
/*
* Source-routed (non-local or virtual) recipient addresses are too
* suspicious for returning an "OK" result. The complicated expression
* below was brought to you by the keyboard of Victor Duchovni, Morgan
* Stanley and hacked up a bit by Wietse.
*/
#define SUSPICIOUS(reply, reply_class) \
(var_allow_untrust_route == 0 \
&& (reply->flags & RESOLVE_FLAG_ROUTED) \
&& strcmp(reply_class, SMTPD_NAME_RECIPIENT) == 0)
/*
* Look up user+foo@domain if the address has an extension, user@domain
* otherwise.
*/
#define LOOKUP_STRATEGY (MA_FIND_FULL | MA_FIND_NOEXT | MA_FIND_DOMAIN \
| MA_FIND_PDMS | MA_FIND_LOCALPART_AT)
if ((maps = (MAPS *) htable_find(map_command_table, table)) == 0) {
msg_warn("%s: unexpected dictionary: %s", myname, table);
value = "451 4.3.5 Server configuration error";
return (check_table_result(state, table, value,
CONST_STR(reply->recipient),
reply_name, reply_class,
def_acl));
}
if ((value = mail_addr_find_strategy(maps, CONST_STR(reply->recipient),
(char **) 0, LOOKUP_STRATEGY)) != 0) {
*found = 1;
status = check_table_result(state, table, value,
CONST_STR(reply->recipient),
reply_name, reply_class, def_acl);
return (status == SMTPD_CHECK_OK && SUSPICIOUS(reply, reply_class) ?
SMTPD_CHECK_DUNNO : status);
} else if (maps->error != 0) {
/* Warning is already logged. */
value = "451 4.3.5 Server configuration error";
return (check_table_result(state, table, value,
CONST_STR(reply->recipient),
reply_name, reply_class,
def_acl));
}
/*
* Undecided when no match found.
*/
return (SMTPD_CHECK_DUNNO);
}
/* Support for different DNSXL lookup results. */
static SMTPD_RBL_STATE dnsxl_stat_soft[1];
#define SMTPD_DNSXL_STAT_SOFT(dnsxl_res) ((dnsxl_res) == dnsxl_stat_soft)
#define SMTPD_DNXSL_STAT_HARD(dnsxl_res) ((dnsxl_res) == 0)
#define SMTPD_DNSXL_STAT_OK(dnsxl_res) \
!(SMTPD_DNXSL_STAT_HARD(dnsxl_res) || SMTPD_DNSXL_STAT_SOFT(dnsxl_res))
/* rbl_pagein - look up an RBL lookup result */
static void *rbl_pagein(const char *query, void *unused_context)
{
DNS_RR *txt_list;
VSTRING *why;
int dns_status;
SMTPD_RBL_STATE *rbl = 0;
DNS_RR *addr_list;
DNS_RR *rr;
DNS_RR *next;
VSTRING *buf;
int space_left;
/*
* Do the query. If the DNS lookup produces no definitive reply, give the
* requestor the benefit of the doubt. We can't block all email simply
* because an RBL server is unavailable.
*
* Don't do this for AAAA records. Yet.
*/
why = vstring_alloc(10);
dns_status = dns_lookup(query, T_A, 0, &addr_list, (VSTRING *) 0, why);
if (dns_status != DNS_OK && dns_status != DNS_NOTFOUND) {
msg_warn("%s: RBL lookup error: %s", query, STR(why));
rbl = dnsxl_stat_soft;
}
vstring_free(why);
if (dns_status != DNS_OK)
return ((void *) rbl);
/*
* Save the result. Yes, we cache negative results as well as positive
* results. Concatenate multiple TXT records, up to some limit.
*/
#define RBL_TXT_LIMIT 500
rbl = (SMTPD_RBL_STATE *) mymalloc(sizeof(*rbl));
dns_status = dns_lookup(query, T_TXT, 0, &txt_list,
(VSTRING *) 0, (VSTRING *) 0);
if (dns_status == DNS_OK) {
buf = vstring_alloc(1);
space_left = RBL_TXT_LIMIT;
for (rr = txt_list; rr != 0 && space_left > 0; rr = next) {
vstring_strncat(buf, rr->data, (int) rr->data_len > space_left ?
space_left : rr->data_len);
space_left = RBL_TXT_LIMIT - VSTRING_LEN(buf);
next = rr->next;
if (next && space_left > 3) {
vstring_strcat(buf, " / ");
space_left -= 3;
}
}
rbl->txt = vstring_export(buf);
dns_rr_free(txt_list);
} else {
if (dns_status == DNS_POLICY)
msg_warn("%s: TXT lookup error: %s",
query, "DNS reply filter drops all results");
rbl->txt = 0;
}
rbl->a = addr_list;
return ((void *) rbl);
}
/* rbl_pageout - discard an RBL lookup result */
static void rbl_pageout(void *data, void *unused_context)
{
SMTPD_RBL_STATE *rbl = (SMTPD_RBL_STATE *) data;
if (SMTPD_DNSXL_STAT_OK(rbl)) {
if (rbl->txt)
myfree(rbl->txt);
if (rbl->a)
dns_rr_free(rbl->a);
myfree((void *) rbl);
}
}
/* rbl_byte_pagein - parse RBL reply pattern, save byte codes */
static void *rbl_byte_pagein(const char *query, void *unused_context)
{
VSTRING *byte_codes = vstring_alloc(100);
char *saved_query = mystrdup(query);
char *saved_byte_codes;
char *err;
if ((err = ip_match_parse(byte_codes, saved_query)) != 0)
msg_fatal("RBL reply error: %s", err);
saved_byte_codes = ip_match_save(byte_codes);
myfree(saved_query);
vstring_free(byte_codes);
return (saved_byte_codes);
}
/* rbl_byte_pageout - discard parsed RBL reply byte codes */
static void rbl_byte_pageout(void *data, void *unused_context)
{
myfree(data);
}
/* rbl_expand_lookup - RBL specific $name expansion */
static const char *rbl_expand_lookup(const char *name, int mode,
void *context)
{
SMTPD_RBL_EXPAND_CONTEXT *rbl_exp = (SMTPD_RBL_EXPAND_CONTEXT *) context;
SMTPD_STATE *state = rbl_exp->state;
#define STREQ(x,y) (*(x) == *(y) && strcmp((x), (y)) == 0)
if (state->expand_buf == 0)
state->expand_buf = vstring_alloc(10);
if (msg_verbose > 1)
msg_info("rbl_expand_lookup: ${%s}", name);
/*
* Be sure to return NULL only for non-existent names.
*/
if (STREQ(name, MAIL_ATTR_RBL_CODE)) {
vstring_sprintf(state->expand_buf, "%d", var_maps_rbl_code);
return (STR(state->expand_buf));
} else if (STREQ(name, MAIL_ATTR_RBL_DOMAIN)) {
return (rbl_exp->domain);
} else if (STREQ(name, MAIL_ATTR_RBL_REASON)) {
return (rbl_exp->txt);
} else if (STREQ(name, MAIL_ATTR_RBL_TXT)) {/* LaMont compat */
return (rbl_exp->txt);
} else if (STREQ(name, MAIL_ATTR_RBL_WHAT)) {
return (rbl_exp->what);
} else if (STREQ(name, MAIL_ATTR_RBL_CLASS)) {
return (rbl_exp->class);
} else {
return (smtpd_expand_lookup(name, mode, (void *) state));
}
}
/* rbl_reject_reply - format reply after RBL reject */
static int rbl_reject_reply(SMTPD_STATE *state, const SMTPD_RBL_STATE *rbl,
const char *rbl_domain,
const char *what,
const char *reply_class)
{
const char *myname = "rbl_reject_reply";
VSTRING *why = 0;
const char *template = 0;
SMTPD_RBL_EXPAND_CONTEXT rbl_exp;
int result;
DSN_SPLIT dp;
int code;
/*
* Use the server-specific reply template or use the default one.
*/
if (*var_rbl_reply_maps) {
template = maps_find(rbl_reply_maps, rbl_domain, DICT_FLAG_NONE);
if (rbl_reply_maps->error)
reject_server_error(state);
}
why = vstring_alloc(100);
rbl_exp.state = state;
rbl_exp.domain = mystrdup(rbl_domain);
(void) split_at(rbl_exp.domain, '=');
rbl_exp.what = what;
rbl_exp.class = reply_class;
rbl_exp.txt = (rbl->txt == 0 ? "" : rbl->txt);
for (;;) {
if (template == 0)
template = var_def_rbl_reply;
if (mac_expand(why, template, MAC_EXP_FLAG_NONE,
STR(smtpd_expand_filter), rbl_expand_lookup,
(void *) &rbl_exp) == 0)
break;
if (template == var_def_rbl_reply)
msg_fatal("%s: bad default rbl reply template: %s",
myname, var_def_rbl_reply);
msg_warn("%s: bad rbl reply template for domain %s: %s",
myname, rbl_domain, template);
template = 0; /* pretend not found */
}
/*
* XXX Impedance mis-match.
*
* Validate the response, that is, the response must begin with a
* three-digit status code, and the first digit must be 4 or 5. If the
* response is bad, log a warning and send a generic response instead.
*/
if ((STR(why)[0] != '4' && STR(why)[0] != '5')
|| !ISDIGIT(STR(why)[1]) || !ISDIGIT(STR(why)[2])
|| STR(why)[3] != ' ') {
msg_warn("rbl response code configuration error: %s", STR(why));
result = smtpd_check_reject(state, MAIL_ERROR_POLICY,
450, "4.7.1", "Service unavailable");
} else {
code = atoi(STR(why));
dsn_split(&dp, "4.7.1", STR(why) + 4);
result = smtpd_check_reject(state, MAIL_ERROR_POLICY,
code,
smtpd_dsn_fix(DSN_STATUS(dp.dsn),
reply_class),
"%s", *dp.text ?
dp.text : "Service unavailable");
}
/*
* Clean up.
*/
myfree(rbl_exp.domain);
vstring_free(why);
return (result);
}
/* rbl_match_addr - match address list */
static int rbl_match_addr(SMTPD_RBL_STATE *rbl, const char *byte_codes)
{
const char *myname = "rbl_match_addr";
DNS_RR *rr;
for (rr = rbl->a; rr != 0; rr = rr->next) {
if (rr->type == T_A) {
if (ip_match_execute(byte_codes, rr->data))
return (1);
} else {
msg_warn("%s: skipping record type %s for query %s",
myname, dns_strtype(rr->type), rr->qname);
}
}
return (0);
}
/* find_dnsxl_addr - look up address in DNSXL */
static const SMTPD_RBL_STATE *find_dnsxl_addr(SMTPD_STATE *state,
const char *rbl_domain,
const char *addr)
{
const char *myname = "find_dnsxl_addr";
ARGV *octets;
VSTRING *query;
int i;
SMTPD_RBL_STATE *rbl;
const char *reply_addr;
const char *byte_codes;
struct addrinfo *res;
unsigned char *ipv6_addr;
query = vstring_alloc(100);
/*
* Reverse the client IPV6 address, represented as 32 hexadecimal
* nibbles. We use the binary address to avoid tricky code. Asking for an
* AAAA record makes no sense here. Just like with IPv4 we use the lookup
* result as a bit mask, not as an IP address.
*/
#ifdef HAS_IPV6
if (valid_ipv6_hostaddr(addr, DONT_GRIPE)) {
if (hostaddr_to_sockaddr(addr, (char *) 0, 0, &res) != 0
|| res->ai_family != PF_INET6)
msg_fatal("%s: unable to convert address %s", myname, addr);
ipv6_addr = (unsigned char *) &SOCK_ADDR_IN6_ADDR(res->ai_addr);
for (i = sizeof(SOCK_ADDR_IN6_ADDR(res->ai_addr)) - 1; i >= 0; i--)
vstring_sprintf_append(query, "%x.%x.",
ipv6_addr[i] & 0xf, ipv6_addr[i] >> 4);
freeaddrinfo(res);
} else
#endif
/*
* Reverse the client IPV4 address, represented as four decimal octet
* values. We use the textual address for convenience.
*/
{
octets = argv_split(addr, ".");
for (i = octets->argc - 1; i >= 0; i--) {
vstring_strcat(query, octets->argv[i]);
vstring_strcat(query, ".");
}
argv_free(octets);
}
/*
* Tack on the RBL domain name and query the DNS for an A record.
*/
vstring_strcat(query, rbl_domain);
reply_addr = split_at(STR(query), '=');
rbl = (SMTPD_RBL_STATE *) ctable_locate(smtpd_rbl_cache, STR(query));
if (reply_addr != 0)
byte_codes = ctable_locate(smtpd_rbl_byte_cache, reply_addr);
/*
* If the record exists, match the result address.
*/
if (SMTPD_DNSXL_STAT_OK(rbl) && reply_addr != 0
&& !rbl_match_addr(rbl, byte_codes))
rbl = 0;
vstring_free(query);
return (rbl);
}
/* reject_rbl_addr - reject address in real-time blackhole list */
static int reject_rbl_addr(SMTPD_STATE *state, const char *rbl_domain,
const char *addr, const char *reply_class)
{
const char *myname = "reject_rbl_addr";
const SMTPD_RBL_STATE *rbl;
if (msg_verbose)
msg_info("%s: %s %s", myname, reply_class, addr);
rbl = find_dnsxl_addr(state, rbl_domain, addr);
if (!SMTPD_DNSXL_STAT_OK(rbl)) {
return (SMTPD_CHECK_DUNNO);
} else {
return (rbl_reject_reply(state, rbl, rbl_domain, addr, reply_class));
}
}
/* permit_dnswl_addr - permit address in DNSWL */
static int permit_dnswl_addr(SMTPD_STATE *state, const char *dnswl_domain,
const char *addr, const char *reply_class)
{
const char *myname = "permit_dnswl_addr";
const SMTPD_RBL_STATE *dnswl_result;
if (msg_verbose)
msg_info("%s: %s", myname, addr);
/* Safety: don't whitelist unauthorized recipients. */
if (strcmp(state->where, SMTPD_CMD_RCPT) == 0 && state->recipient != 0
&& permit_auth_destination(state, state->recipient) != SMTPD_CHECK_OK)
return (SMTPD_CHECK_DUNNO);
dnswl_result = find_dnsxl_addr(state, dnswl_domain, addr);
if (SMTPD_DNXSL_STAT_HARD(dnswl_result)) {
return (SMTPD_CHECK_DUNNO);
} else if (SMTPD_DNSXL_STAT_SOFT(dnswl_result)) {
/* XXX: Make configurable as dnswl_tempfail_action. */
DEFER_IF_REJECT3(state, MAIL_ERROR_POLICY,
450, "4.7.1",
"<%s>: %s rejected: %s",
addr, reply_class,
"Service unavailable");
return (SMTPD_CHECK_DUNNO);
} else if (SMTPD_DNSXL_STAT_OK(dnswl_result)) {
return (SMTPD_CHECK_OK);
} else {
/* Future proofing, in case find_dnsxl_addr() result is changed. */
msg_panic("%s: find_dnsxl_addr API failure", myname);
}
}
/* find_dnsxl_domain - reject if domain in real-time blackhole list */
static const SMTPD_RBL_STATE *find_dnsxl_domain(SMTPD_STATE *state,
const char *rbl_domain, const char *what)
{
VSTRING *query;
SMTPD_RBL_STATE *rbl;
const char *domain;
const char *reply_addr;
const char *byte_codes;
const char *suffix;
const char *adomain;
/*
* Extract the domain, tack on the RBL domain name and query the DNS for
* an A record.
*/
if ((domain = strrchr(what, '@')) != 0) {
domain += 1;
if (domain[0] == '[')
return (SMTPD_CHECK_DUNNO);
} else
domain = what;
/*
* XXX Some Spamhaus RHSBL rejects lookups with "No IP queries" even if
* the name has an alphanumerical prefix. We play safe, and skip both
* RHSBL and RHSWL queries for names ending in a numerical suffix.
*/
if (domain[0] == 0)
return (SMTPD_CHECK_DUNNO);
suffix = strrchr(domain, '.');
if (alldig(suffix == 0 ? domain : suffix + 1))
return (SMTPD_CHECK_DUNNO);
/*
* Fix 20140706: convert domain to ASCII.
*/
#ifndef NO_EAI
if (!allascii(domain) && (adomain = midna_domain_to_ascii(domain)) != 0) {
if (msg_verbose)
msg_info("%s asciified to %s", domain, adomain);
domain = adomain;
}
#endif
if (domain[0] == 0 || valid_hostname(domain, DONT_GRIPE) == 0)
return (SMTPD_CHECK_DUNNO);
query = vstring_alloc(100);
vstring_sprintf(query, "%s.%s", domain, rbl_domain);
reply_addr = split_at(STR(query), '=');
rbl = (SMTPD_RBL_STATE *) ctable_locate(smtpd_rbl_cache, STR(query));
if (reply_addr != 0)
byte_codes = ctable_locate(smtpd_rbl_byte_cache, reply_addr);
/*
* If the record exists, match the result address.
*/
if (SMTPD_DNSXL_STAT_OK(rbl) && reply_addr != 0
&& !rbl_match_addr(rbl, byte_codes))
rbl = 0;
vstring_free(query);
return (rbl);
}
/* reject_rbl_domain - reject if domain in real-time blackhole list */
static int reject_rbl_domain(SMTPD_STATE *state, const char *rbl_domain,
const char *what, const char *reply_class)
{
const char *myname = "reject_rbl_domain";
const SMTPD_RBL_STATE *rbl;
if (msg_verbose)
msg_info("%s: %s %s", myname, rbl_domain, what);
rbl = find_dnsxl_domain(state, rbl_domain, what);
if (!SMTPD_DNSXL_STAT_OK(rbl)) {
return (SMTPD_CHECK_DUNNO);
} else {
return (rbl_reject_reply(state, rbl, rbl_domain, what, reply_class));
}
}
/* permit_dnswl_domain - permit domain in DNSWL */
static int permit_dnswl_domain(SMTPD_STATE *state, const char *dnswl_domain,
const char *what, const char *reply_class)
{
const char *myname = "permit_dnswl_domain";
const SMTPD_RBL_STATE *dnswl_result;
if (msg_verbose)
msg_info("%s: %s", myname, what);
/* Safety: don't whitelist unauthorized recipients. */
if (strcmp(state->where, SMTPD_CMD_RCPT) == 0 && state->recipient != 0
&& permit_auth_destination(state, state->recipient) != SMTPD_CHECK_OK)
return (SMTPD_CHECK_DUNNO);
dnswl_result = find_dnsxl_domain(state, dnswl_domain, what);
if (SMTPD_DNXSL_STAT_HARD(dnswl_result)) {
return (SMTPD_CHECK_DUNNO);
} else if (SMTPD_DNSXL_STAT_SOFT(dnswl_result)) {
/* XXX: Make configurable as rhswl_tempfail_action. */
DEFER_IF_REJECT3(state, MAIL_ERROR_POLICY,
450, "4.7.1",
"<%s>: %s rejected: %s",
what, reply_class,
"Service unavailable");
return (SMTPD_CHECK_DUNNO);
} else if (SMTPD_DNSXL_STAT_OK(dnswl_result)) {
return (SMTPD_CHECK_OK);
} else {
/* Future proofing, in case find_dnsxl_addr() result is changed. */
msg_panic("%s: find_dnsxl_addr API failure", myname);
}
}
/* reject_maps_rbl - reject if client address in real-time blackhole list */
static int reject_maps_rbl(SMTPD_STATE *state)
{
const char *myname = "reject_maps_rbl";
char *saved_domains = mystrdup(var_maps_rbl_domains);
char *bp = saved_domains;
char *rbl_domain;
int result = SMTPD_CHECK_DUNNO;
static int warned;
if (msg_verbose)
msg_info("%s: %s", myname, state->addr);
if (warned == 0) {
warned++;
msg_warn("support for restriction \"%s\" will be removed from %s; "
"use \"%s domain-name\" instead",
REJECT_MAPS_RBL, var_mail_name, REJECT_RBL_CLIENT);
}
while ((rbl_domain = mystrtok(&bp, CHARS_COMMA_SP)) != 0) {
result = reject_rbl_addr(state, rbl_domain, state->addr,
SMTPD_NAME_CLIENT);
if (result != SMTPD_CHECK_DUNNO)
break;
}
/*
* Clean up.
*/
myfree(saved_domains);
return (result);
}
#ifdef USE_SASL_AUTH
/* reject_auth_sender_login_mismatch - logged in client must own sender address */
static int reject_auth_sender_login_mismatch(SMTPD_STATE *state, const char *sender, int allow_unknown_sender)
{
const RESOLVE_REPLY *reply;
const char *owners;
char *saved_owners;
char *cp;
char *name;
int found = 0;
#define ALLOW_UNKNOWN_SENDER 1
#define FORBID_UNKNOWN_SENDER 0
/*
* Reject if the client is logged in and does not own the sender address.
*/
if (smtpd_sender_login_maps && state->sasl_username) {
reply = smtpd_resolve_addr(state->recipient, sender);
if (reply->flags & RESOLVE_FLAG_FAIL)
reject_dict_retry(state, sender);
if ((owners = check_mail_addr_find(state, sender, smtpd_sender_login_maps,
STR(reply->recipient), (char **) 0)) != 0) {
cp = saved_owners = mystrdup(owners);
while ((name = mystrtok(&cp, CHARS_COMMA_SP)) != 0) {
if (strcasecmp_utf8(state->sasl_username, name) == 0) {
found = 1;
break;
}
}
myfree(saved_owners);
} else if (allow_unknown_sender)
return (SMTPD_CHECK_DUNNO);
if (!found)
return (smtpd_check_reject(state, MAIL_ERROR_POLICY, 553, "5.7.1",
"<%s>: Sender address rejected: not owned by user %s",
sender, state->sasl_username));
}
return (SMTPD_CHECK_DUNNO);
}
/* reject_unauth_sender_login_mismatch - sender requires client is logged in */
static int reject_unauth_sender_login_mismatch(SMTPD_STATE *state, const char *sender)
{
const RESOLVE_REPLY *reply;
/*
* Reject if the client is not logged in and the sender address has an
* owner.
*/
if (smtpd_sender_login_maps && !state->sasl_username) {
reply = smtpd_resolve_addr(state->recipient, sender);
if (reply->flags & RESOLVE_FLAG_FAIL)
reject_dict_retry(state, sender);
if (check_mail_addr_find(state, sender, smtpd_sender_login_maps,
STR(reply->recipient), (char **) 0) != 0)
return (smtpd_check_reject(state, MAIL_ERROR_POLICY, 553, "5.7.1",
"<%s>: Sender address rejected: not logged in", sender));
}
return (SMTPD_CHECK_DUNNO);
}
#endif
/* valid_utf8_action - validate UTF-8 policy server response */
static int valid_utf8_action(const char *server, const char *action)
{
int retval;
if ((retval = valid_utf8_string(action, strlen(action))) == 0)
msg_warn("malformed UTF-8 in policy server %s response: \"%s\"",
server, action);
return (retval);
}
/* check_policy_service - check delegated policy service */
static int check_policy_service(SMTPD_STATE *state, const char *server,
const char *reply_name, const char *reply_class,
const char *def_acl)
{
static VSTRING *action = 0;
SMTPD_POLICY_CLNT *policy_clnt;
#ifdef USE_TLS
VSTRING *subject_buf;
VSTRING *issuer_buf;
const char *subject;
const char *issuer;
#endif
int ret;
/*
* Sanity check.
*/
if (!policy_clnt_table
|| (policy_clnt = (SMTPD_POLICY_CLNT *)
htable_find(policy_clnt_table, server)) == 0)
msg_panic("check_policy_service: no client endpoint for server %s",
server);
/*
* Initialize.
*/
if (action == 0)
action = vstring_alloc(10);
#ifdef USE_TLS
#define ENCODE_CN(coded_CN, coded_CN_buf, CN) do { \
if (!TLS_CERT_IS_TRUSTED(state->tls_context) || *(CN) == 0) { \
coded_CN_buf = 0; \
coded_CN = ""; \
} else { \
coded_CN_buf = vstring_alloc(strlen(CN) + 1); \
xtext_quote(coded_CN_buf, CN, ""); \
coded_CN = STR(coded_CN_buf); \
} \
} while (0);
ENCODE_CN(subject, subject_buf, state->tls_context->peer_CN);
ENCODE_CN(issuer, issuer_buf, state->tls_context->issuer_CN);
#endif
if (attr_clnt_request(policy_clnt->client,
ATTR_FLAG_NONE, /* Query attributes. */
SEND_ATTR_STR(MAIL_ATTR_REQ, "smtpd_access_policy"),
SEND_ATTR_STR(MAIL_ATTR_PROTO_STATE, state->where),
SEND_ATTR_STR(MAIL_ATTR_ACT_PROTO_NAME, state->protocol),
SEND_ATTR_STR(MAIL_ATTR_ACT_CLIENT_ADDR, state->addr),
SEND_ATTR_STR(MAIL_ATTR_ACT_CLIENT_NAME, state->name),
SEND_ATTR_STR(MAIL_ATTR_ACT_CLIENT_PORT, state->port),
SEND_ATTR_STR(MAIL_ATTR_ACT_REVERSE_CLIENT_NAME,
state->reverse_name),
SEND_ATTR_STR(MAIL_ATTR_ACT_SERVER_ADDR,
state->dest_addr),
SEND_ATTR_STR(MAIL_ATTR_ACT_SERVER_PORT,
state->dest_port),
SEND_ATTR_STR(MAIL_ATTR_ACT_HELO_NAME,
state->helo_name ? state->helo_name : ""),
SEND_ATTR_STR(MAIL_ATTR_SENDER,
state->sender ? state->sender : ""),
SEND_ATTR_STR(MAIL_ATTR_RECIP,
state->recipient ? state->recipient : ""),
SEND_ATTR_INT(MAIL_ATTR_RCPT_COUNT,
((strcasecmp(state->where, SMTPD_CMD_DATA) == 0) ||
(strcasecmp(state->where, SMTPD_AFTER_DOT) == 0)) ?
state->rcpt_count : 0),
SEND_ATTR_STR(MAIL_ATTR_QUEUEID,
state->queue_id ? state->queue_id : ""),
SEND_ATTR_STR(MAIL_ATTR_INSTANCE,
STR(state->instance)),
SEND_ATTR_LONG(MAIL_ATTR_SIZE,
(unsigned long) (state->act_size > 0 ?
state->act_size : state->msg_size)),
SEND_ATTR_STR(MAIL_ATTR_ETRN_DOMAIN,
state->etrn_name ? state->etrn_name : ""),
SEND_ATTR_STR(MAIL_ATTR_STRESS, var_stress),
#ifdef USE_SASL_AUTH
SEND_ATTR_STR(MAIL_ATTR_SASL_METHOD,
state->sasl_method ? state->sasl_method : ""),
SEND_ATTR_STR(MAIL_ATTR_SASL_USERNAME,
state->sasl_username ? state->sasl_username : ""),
SEND_ATTR_STR(MAIL_ATTR_SASL_SENDER,
state->sasl_sender ? state->sasl_sender : ""),
#endif
#ifdef USE_TLS
#define IF_ENCRYPTED(x, y) ((state->tls_context && ((x) != 0)) ? (x) : (y))
SEND_ATTR_STR(MAIL_ATTR_CCERT_SUBJECT, subject),
SEND_ATTR_STR(MAIL_ATTR_CCERT_ISSUER, issuer),
/*
* When directly checking the fingerprint, it is OK if the issuing CA is
* not trusted.
*/
SEND_ATTR_STR(MAIL_ATTR_CCERT_CERT_FPRINT,
IF_ENCRYPTED(state->tls_context->peer_cert_fprint, "")),
SEND_ATTR_STR(MAIL_ATTR_CCERT_PKEY_FPRINT,
IF_ENCRYPTED(state->tls_context->peer_pkey_fprint, "")),
SEND_ATTR_STR(MAIL_ATTR_CRYPTO_PROTOCOL,
IF_ENCRYPTED(state->tls_context->protocol, "")),
SEND_ATTR_STR(MAIL_ATTR_CRYPTO_CIPHER,
IF_ENCRYPTED(state->tls_context->cipher_name, "")),
SEND_ATTR_INT(MAIL_ATTR_CRYPTO_KEYSIZE,
IF_ENCRYPTED(state->tls_context->cipher_usebits, 0)),
#endif
SEND_ATTR_STR(MAIL_ATTR_POL_CONTEXT,
policy_clnt->policy_context),
ATTR_TYPE_END,
ATTR_FLAG_MISSING, /* Reply attributes. */
RECV_ATTR_STR(MAIL_ATTR_ACTION, action),
ATTR_TYPE_END) != 1
|| (var_smtputf8_enable && valid_utf8_action(server, STR(action)) == 0)) {
NOCLOBBER static int nesting_level = 0;
jmp_buf savebuf;
int status;
/*
* Safety to prevent recursive execution of the default action.
*/
nesting_level += 1;
memcpy(ADDROF(savebuf), ADDROF(smtpd_check_buf), sizeof(savebuf));
status = setjmp(smtpd_check_buf);
if (status != 0) {
nesting_level -= 1;
memcpy(ADDROF(smtpd_check_buf), ADDROF(savebuf),
sizeof(smtpd_check_buf));
longjmp(smtpd_check_buf, status);
}
ret = check_table_result(state, server, nesting_level == 1 ?
policy_clnt->def_action :
DEF_SMTPD_POLICY_DEF_ACTION,
"policy query", reply_name,
reply_class, def_acl);
nesting_level -= 1;
memcpy(ADDROF(smtpd_check_buf), ADDROF(savebuf),
sizeof(smtpd_check_buf));
} else {
/*
* XXX This produces bogus error messages when the reply is
* malformed.
*/
ret = check_table_result(state, server, STR(action),
"policy query", reply_name,
reply_class, def_acl);
}
#ifdef USE_TLS
if (subject_buf)
vstring_free(subject_buf);
if (issuer_buf)
vstring_free(issuer_buf);
#endif
return (ret);
}
/* is_map_command - restriction has form: check_xxx_access type:name */
static int is_map_command(SMTPD_STATE *state, const char *name,
const char *command, char ***argp)
{
/*
* This is a three-valued function: (a) this is not a check_xxx_access
* command, (b) this is a malformed check_xxx_access command, (c) this is
* a well-formed check_xxx_access command. That's too clumsy for function
* result values, so we use regular returns for (a) and (c), and use long
* jumps for the error case (b).
*/
if (strcasecmp(name, command) != 0) {
return (0);
} else if (*(*argp + 1) == 0 || strchr(*(*argp += 1), ':') == 0) {
msg_warn("restriction %s: bad argument \"%s\": need maptype:mapname",
command, **argp);
reject_server_error(state);
} else {
return (1);
}
}
/* forbid_whitelist - disallow whitelisting */
static void forbid_whitelist(SMTPD_STATE *state, const char *name,
int status, const char *target)
{
if (status == SMTPD_CHECK_OK) {
msg_warn("restriction %s returns OK for %s", name, target);
msg_warn("this is not allowed for security reasons");
msg_warn("use DUNNO instead of OK if you want to make an exception");
reject_server_error(state);
}
}
/* generic_checks - generic restrictions */
static int generic_checks(SMTPD_STATE *state, ARGV *restrictions,
const char *reply_name,
const char *reply_class,
const char *def_acl)
{
const char *myname = "generic_checks";
char **cpp;
const char *name;
int status = 0;
ARGV *list;
int found;
int saved_recursion = state->recursion++;
if (msg_verbose)
msg_info(">>> START %s RESTRICTIONS <<<", reply_class);
for (cpp = restrictions->argv; (name = *cpp) != 0; cpp++) {
if (state->discard != 0)
break;
if (msg_verbose)
msg_info("%s: name=%s", myname, name);
/*
* Pseudo restrictions.
*/
if (strcasecmp(name, WARN_IF_REJECT) == 0) {
if (state->warn_if_reject == 0)
state->warn_if_reject = state->recursion;
continue;
}
/*
* Spoof the is_map_command() routine, so that we do not have to make
* special cases for the implicit short-hand access map notation.
*/
#define NO_DEF_ACL 0
if (strchr(name, ':') != 0) {
if (def_acl == NO_DEF_ACL) {
msg_warn("specify one of (%s, %s, %s, %s, %s, %s) before %s restriction \"%s\"",
CHECK_CLIENT_ACL, CHECK_REVERSE_CLIENT_ACL, CHECK_HELO_ACL, CHECK_SENDER_ACL,
CHECK_RECIP_ACL, CHECK_ETRN_ACL, reply_class, name);
reject_server_error(state);
}
name = def_acl;
cpp -= 1;
}
/*
* Generic restrictions.
*/
if (strcasecmp(name, PERMIT_ALL) == 0) {
status = smtpd_acl_permit(state, name, reply_class,
reply_name, NO_PRINT_ARGS);
if (status == SMTPD_CHECK_OK && cpp[1] != 0)
msg_warn("restriction `%s' after `%s' is ignored",
cpp[1], PERMIT_ALL);
} else if (strcasecmp(name, DEFER_ALL) == 0) {
status = smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_defer_code, "4.3.2",
"<%s>: %s rejected: Try again later",
reply_name, reply_class);
if (cpp[1] != 0 && state->warn_if_reject == 0)
msg_warn("restriction `%s' after `%s' is ignored",
cpp[1], DEFER_ALL);
} else if (strcasecmp(name, REJECT_ALL) == 0) {
status = smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_reject_code, "5.7.1",
"<%s>: %s rejected: Access denied",
reply_name, reply_class);
if (cpp[1] != 0 && state->warn_if_reject == 0)
msg_warn("restriction `%s' after `%s' is ignored",
cpp[1], REJECT_ALL);
} else if (strcasecmp(name, REJECT_UNAUTH_PIPE) == 0) {
status = reject_unauth_pipelining(state, reply_name, reply_class);
} else if (strcasecmp(name, CHECK_POLICY_SERVICE) == 0) {
if (cpp[1] == 0 || strchr(cpp[1], ':') == 0) {
msg_warn("restriction %s must be followed by transport:server",
CHECK_POLICY_SERVICE);
reject_server_error(state);
} else
status = check_policy_service(state, *++cpp, reply_name,
reply_class, def_acl);
} else if (strcasecmp(name, DEFER_IF_PERMIT) == 0) {
status = DEFER_IF_PERMIT2(DEFER_IF_PERMIT_ACT,
state, MAIL_ERROR_POLICY,
450, "4.7.0",
"<%s>: %s rejected: defer_if_permit requested",
reply_name, reply_class);
} else if (strcasecmp(name, DEFER_IF_REJECT) == 0) {
DEFER_IF_REJECT2(state, MAIL_ERROR_POLICY,
450, "4.7.0",
"<%s>: %s rejected: defer_if_reject requested",
reply_name, reply_class);
} else if (strcasecmp(name, SLEEP) == 0) {
if (cpp[1] == 0 || alldig(cpp[1]) == 0) {
msg_warn("restriction %s must be followed by number", SLEEP);
reject_server_error(state);
} else
sleep(atoi(*++cpp));
} else if (strcasecmp(name, REJECT_PLAINTEXT_SESSION) == 0) {
status = reject_plaintext_session(state);
}
/*
* Client name/address restrictions.
*/
else if (strcasecmp(name, REJECT_UNKNOWN_CLIENT_HOSTNAME) == 0
|| strcasecmp(name, REJECT_UNKNOWN_CLIENT) == 0) {
status = reject_unknown_client(state);
} else if (strcasecmp(name, REJECT_UNKNOWN_REVERSE_HOSTNAME) == 0) {
status = reject_unknown_reverse_name(state);
} else if (strcasecmp(name, PERMIT_INET_INTERFACES) == 0) {
status = permit_inet_interfaces(state);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_CLIENT,
state->namaddr, NO_PRINT_ARGS);
} else if (strcasecmp(name, PERMIT_MYNETWORKS) == 0) {
status = permit_mynetworks(state);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_CLIENT,
state->namaddr, NO_PRINT_ARGS);
} else if (is_map_command(state, name, CHECK_CLIENT_ACL, &cpp)) {
status = check_namadr_access(state, *cpp, state->name, state->addr,
FULL, &found, state->namaddr,
SMTPD_NAME_CLIENT, def_acl);
} else if (is_map_command(state, name, CHECK_REVERSE_CLIENT_ACL, &cpp)) {
status = check_namadr_access(state, *cpp, state->reverse_name, state->addr,
FULL, &found, state->reverse_name,
SMTPD_NAME_REV_CLIENT, def_acl);
forbid_whitelist(state, name, status, state->reverse_name);
} else if (strcasecmp(name, REJECT_MAPS_RBL) == 0) {
status = reject_maps_rbl(state);
} else if (strcasecmp(name, REJECT_RBL_CLIENT) == 0
|| strcasecmp(name, REJECT_RBL) == 0) {
if (cpp[1] == 0)
msg_warn("restriction %s requires domain name argument", name);
else
status = reject_rbl_addr(state, *(cpp += 1), state->addr,
SMTPD_NAME_CLIENT);
} else if (strcasecmp(name, PERMIT_DNSWL_CLIENT) == 0) {
if (cpp[1] == 0)
msg_warn("restriction %s requires domain name argument", name);
else {
status = permit_dnswl_addr(state, *(cpp += 1), state->addr,
SMTPD_NAME_CLIENT);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_CLIENT,
state->namaddr, NO_PRINT_ARGS);
}
} else if (strcasecmp(name, REJECT_RHSBL_CLIENT) == 0) {
if (cpp[1] == 0)
msg_warn("restriction %s requires domain name argument",
name);
else {
cpp += 1;
if (strcasecmp(state->name, "unknown") != 0)
status = reject_rbl_domain(state, *cpp, state->name,
SMTPD_NAME_CLIENT);
}
} else if (strcasecmp(name, PERMIT_RHSWL_CLIENT) == 0) {
if (cpp[1] == 0)
msg_warn("restriction %s requires domain name argument",
name);
else {
cpp += 1;
if (strcasecmp(state->name, "unknown") != 0) {
status = permit_dnswl_domain(state, *cpp, state->name,
SMTPD_NAME_CLIENT);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name,
SMTPD_NAME_CLIENT, state->namaddr, NO_PRINT_ARGS);
}
}
} else if (strcasecmp(name, REJECT_RHSBL_REVERSE_CLIENT) == 0) {
if (cpp[1] == 0)
msg_warn("restriction %s requires domain name argument",
name);
else {
cpp += 1;
if (strcasecmp(state->reverse_name, "unknown") != 0)
status = reject_rbl_domain(state, *cpp, state->reverse_name,
SMTPD_NAME_REV_CLIENT);
}
} else if (is_map_command(state, name, CHECK_CCERT_ACL, &cpp)) {
status = check_ccert_access(state, *cpp, def_acl);
#ifdef USE_SASL_AUTH
} else if (is_map_command(state, name, CHECK_SASL_ACL, &cpp)) {
if (var_smtpd_sasl_enable) {
if (state->sasl_username && state->sasl_username[0])
status = check_sasl_access(state, *cpp, def_acl);
} else
#endif
msg_warn("restriction `%s' ignored: no SASL support", name);
} else if (is_map_command(state, name, CHECK_CLIENT_NS_ACL, &cpp)) {
if (strcasecmp(state->name, "unknown") != 0) {
status = check_server_access(state, *cpp, state->name,
T_NS, state->namaddr,
SMTPD_NAME_CLIENT, def_acl);
forbid_whitelist(state, name, status, state->name);
}
} else if (is_map_command(state, name, CHECK_CLIENT_MX_ACL, &cpp)) {
if (strcasecmp(state->name, "unknown") != 0) {
status = check_server_access(state, *cpp, state->name,
T_MX, state->namaddr,
SMTPD_NAME_CLIENT, def_acl);
forbid_whitelist(state, name, status, state->name);
}
} else if (is_map_command(state, name, CHECK_CLIENT_A_ACL, &cpp)) {
if (strcasecmp(state->name, "unknown") != 0) {
status = check_server_access(state, *cpp, state->name,
T_A, state->namaddr,
SMTPD_NAME_CLIENT, def_acl);
forbid_whitelist(state, name, status, state->name);
}
} else if (is_map_command(state, name, CHECK_REVERSE_CLIENT_NS_ACL, &cpp)) {
if (strcasecmp(state->reverse_name, "unknown") != 0) {
status = check_server_access(state, *cpp, state->reverse_name,
T_NS, state->reverse_name,
SMTPD_NAME_REV_CLIENT, def_acl);
forbid_whitelist(state, name, status, state->reverse_name);
}
} else if (is_map_command(state, name, CHECK_REVERSE_CLIENT_MX_ACL, &cpp)) {
if (strcasecmp(state->reverse_name, "unknown") != 0) {
status = check_server_access(state, *cpp, state->reverse_name,
T_MX, state->reverse_name,
SMTPD_NAME_REV_CLIENT, def_acl);
forbid_whitelist(state, name, status, state->reverse_name);
}
} else if (is_map_command(state, name, CHECK_REVERSE_CLIENT_A_ACL, &cpp)) {
if (strcasecmp(state->reverse_name, "unknown") != 0) {
status = check_server_access(state, *cpp, state->reverse_name,
T_A, state->reverse_name,
SMTPD_NAME_REV_CLIENT, def_acl);
forbid_whitelist(state, name, status, state->reverse_name);
}
}
/*
* HELO/EHLO parameter restrictions.
*/
else if (is_map_command(state, name, CHECK_HELO_ACL, &cpp)) {
if (state->helo_name)
status = check_domain_access(state, *cpp, state->helo_name,
FULL, &found, state->helo_name,
SMTPD_NAME_HELO, def_acl);
} else if (strcasecmp(name, REJECT_INVALID_HELO_HOSTNAME) == 0
|| strcasecmp(name, REJECT_INVALID_HOSTNAME) == 0) {
if (state->helo_name) {
if (*state->helo_name != '[')
status = reject_invalid_hostname(state, state->helo_name,
state->helo_name, SMTPD_NAME_HELO);
else
status = reject_invalid_hostaddr(state, state->helo_name,
state->helo_name, SMTPD_NAME_HELO);
}
} else if (strcasecmp(name, REJECT_UNKNOWN_HELO_HOSTNAME) == 0
|| strcasecmp(name, REJECT_UNKNOWN_HOSTNAME) == 0) {
if (state->helo_name) {
if (*state->helo_name != '[')
status = reject_unknown_hostname(state, state->helo_name,
state->helo_name, SMTPD_NAME_HELO);
else
status = reject_invalid_hostaddr(state, state->helo_name,
state->helo_name, SMTPD_NAME_HELO);
}
} else if (strcasecmp(name, PERMIT_NAKED_IP_ADDR) == 0) {
msg_warn("restriction %s is deprecated. Use %s or %s instead",
PERMIT_NAKED_IP_ADDR, PERMIT_MYNETWORKS, PERMIT_SASL_AUTH);
if (state->helo_name) {
if (state->helo_name[strspn(state->helo_name, "0123456789.:")] == 0
&& (status = reject_invalid_hostaddr(state, state->helo_name,
state->helo_name, SMTPD_NAME_HELO)) == 0)
status = smtpd_acl_permit(state, name, SMTPD_NAME_HELO,
state->helo_name, NO_PRINT_ARGS);
}
} else if (is_map_command(state, name, CHECK_HELO_NS_ACL, &cpp)) {
if (state->helo_name) {
status = check_server_access(state, *cpp, state->helo_name,
T_NS, state->helo_name,
SMTPD_NAME_HELO, def_acl);
forbid_whitelist(state, name, status, state->helo_name);
}
} else if (is_map_command(state, name, CHECK_HELO_MX_ACL, &cpp)) {
if (state->helo_name) {
status = check_server_access(state, *cpp, state->helo_name,
T_MX, state->helo_name,
SMTPD_NAME_HELO, def_acl);
forbid_whitelist(state, name, status, state->helo_name);
}
} else if (is_map_command(state, name, CHECK_HELO_A_ACL, &cpp)) {
if (state->helo_name) {
status = check_server_access(state, *cpp, state->helo_name,
T_A, state->helo_name,
SMTPD_NAME_HELO, def_acl);
forbid_whitelist(state, name, status, state->helo_name);
}
} else if (strcasecmp(name, REJECT_NON_FQDN_HELO_HOSTNAME) == 0
|| strcasecmp(name, REJECT_NON_FQDN_HOSTNAME) == 0) {
if (state->helo_name) {
if (*state->helo_name != '[')
status = reject_non_fqdn_hostname(state, state->helo_name,
state->helo_name, SMTPD_NAME_HELO);
else
status = reject_invalid_hostaddr(state, state->helo_name,
state->helo_name, SMTPD_NAME_HELO);
}
} else if (strcasecmp(name, REJECT_RHSBL_HELO) == 0) {
if (cpp[1] == 0)
msg_warn("restriction %s requires domain name argument",
name);
else {
cpp += 1;
if (state->helo_name)
status = reject_rbl_domain(state, *cpp, state->helo_name,
SMTPD_NAME_HELO);
}
}
/*
* Sender mail address restrictions.
*/
else if (is_map_command(state, name, CHECK_SENDER_ACL, &cpp)) {
if (state->sender && *state->sender)
status = check_mail_access(state, *cpp, state->sender,
&found, state->sender,
SMTPD_NAME_SENDER, def_acl);
if (state->sender && !*state->sender)
status = check_access(state, *cpp, var_smtpd_null_key, FULL,
&found, state->sender,
SMTPD_NAME_SENDER, def_acl);
} else if (strcasecmp(name, REJECT_UNKNOWN_ADDRESS) == 0) {
if (state->sender && *state->sender)
status = reject_unknown_address(state, state->sender,
state->sender, SMTPD_NAME_SENDER);
} else if (strcasecmp(name, REJECT_UNKNOWN_SENDDOM) == 0) {
if (state->sender && *state->sender)
status = reject_unknown_address(state, state->sender,
state->sender, SMTPD_NAME_SENDER);
} else if (strcasecmp(name, REJECT_UNVERIFIED_SENDER) == 0) {
if (state->sender && *state->sender)
status = reject_unverified_address(state, state->sender,
state->sender, SMTPD_NAME_SENDER,
var_unv_from_dcode, var_unv_from_rcode,
unv_from_tf_act,
var_unv_from_why);
} else if (strcasecmp(name, REJECT_NON_FQDN_SENDER) == 0) {
if (state->sender && *state->sender)
status = reject_non_fqdn_address(state, state->sender,
state->sender, SMTPD_NAME_SENDER);
} else if (strcasecmp(name, REJECT_AUTH_SENDER_LOGIN_MISMATCH) == 0) {
#ifdef USE_SASL_AUTH
if (var_smtpd_sasl_enable) {
if (state->sender && *state->sender)
status = reject_auth_sender_login_mismatch(state,
state->sender, FORBID_UNKNOWN_SENDER);
} else
#endif
msg_warn("restriction `%s' ignored: no SASL support", name);
} else if (strcasecmp(name, REJECT_KNOWN_SENDER_LOGIN_MISMATCH) == 0) {
#ifdef USE_SASL_AUTH
if (var_smtpd_sasl_enable) {
if (state->sender && *state->sender) {
if (state->sasl_username)
status = reject_auth_sender_login_mismatch(state,
state->sender, ALLOW_UNKNOWN_SENDER);
else
status = reject_unauth_sender_login_mismatch(state, state->sender);
}
} else
#endif
msg_warn("restriction `%s' ignored: no SASL support", name);
} else if (strcasecmp(name, REJECT_UNAUTH_SENDER_LOGIN_MISMATCH) == 0) {
#ifdef USE_SASL_AUTH
if (var_smtpd_sasl_enable) {
if (state->sender && *state->sender)
status = reject_unauth_sender_login_mismatch(state, state->sender);
} else
#endif
msg_warn("restriction `%s' ignored: no SASL support", name);
} else if (is_map_command(state, name, CHECK_SENDER_NS_ACL, &cpp)) {
if (state->sender && *state->sender) {
status = check_server_access(state, *cpp, state->sender,
T_NS, state->sender,
SMTPD_NAME_SENDER, def_acl);
forbid_whitelist(state, name, status, state->sender);
}
} else if (is_map_command(state, name, CHECK_SENDER_MX_ACL, &cpp)) {
if (state->sender && *state->sender) {
status = check_server_access(state, *cpp, state->sender,
T_MX, state->sender,
SMTPD_NAME_SENDER, def_acl);
forbid_whitelist(state, name, status, state->sender);
}
} else if (is_map_command(state, name, CHECK_SENDER_A_ACL, &cpp)) {
if (state->sender && *state->sender) {
status = check_server_access(state, *cpp, state->sender,
T_A, state->sender,
SMTPD_NAME_SENDER, def_acl);
forbid_whitelist(state, name, status, state->sender);
}
} else if (strcasecmp(name, REJECT_RHSBL_SENDER) == 0) {
if (cpp[1] == 0)
msg_warn("restriction %s requires domain name argument", name);
else {
cpp += 1;
if (state->sender && *state->sender)
status = reject_rbl_domain(state, *cpp, state->sender,
SMTPD_NAME_SENDER);
}
} else if (strcasecmp(name, REJECT_UNLISTED_SENDER) == 0) {
if (state->sender && *state->sender)
status = check_sender_rcpt_maps(state, state->sender);
}
/*
* Recipient mail address restrictions.
*/
else if (is_map_command(state, name, CHECK_RECIP_ACL, &cpp)) {
if (state->recipient)
status = check_mail_access(state, *cpp, state->recipient,
&found, state->recipient,
SMTPD_NAME_RECIPIENT, def_acl);
} else if (strcasecmp(name, PERMIT_MX_BACKUP) == 0) {
if (state->recipient) {
status = permit_mx_backup(state, state->recipient,
state->recipient, SMTPD_NAME_RECIPIENT);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_RECIPIENT,
state->recipient, NO_PRINT_ARGS);
}
} else if (strcasecmp(name, PERMIT_AUTH_DEST) == 0) {
if (state->recipient) {
status = permit_auth_destination(state, state->recipient);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_RECIPIENT,
state->recipient, NO_PRINT_ARGS);
}
} else if (strcasecmp(name, REJECT_UNAUTH_DEST) == 0) {
if (state->recipient)
status = reject_unauth_destination(state, state->recipient,
var_relay_code, "5.7.1");
} else if (strcasecmp(name, DEFER_UNAUTH_DEST) == 0) {
if (state->recipient)
status = reject_unauth_destination(state, state->recipient,
var_relay_code - 100, "4.7.1");
} else if (strcasecmp(name, CHECK_RELAY_DOMAINS) == 0) {
if (state->recipient)
status = check_relay_domains(state, state->recipient,
state->recipient, SMTPD_NAME_RECIPIENT);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_RECIPIENT,
state->recipient, NO_PRINT_ARGS);
if (cpp[1] != 0 && state->warn_if_reject == 0)
msg_warn("restriction `%s' after `%s' is ignored",
cpp[1], CHECK_RELAY_DOMAINS);
} else if (strcasecmp(name, PERMIT_SASL_AUTH) == 0) {
#ifdef USE_SASL_AUTH
if (smtpd_sasl_is_active(state)) {
status = permit_sasl_auth(state,
SMTPD_CHECK_OK, SMTPD_CHECK_DUNNO);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_CLIENT,
state->namaddr, NO_PRINT_ARGS);
}
#endif
} else if (strcasecmp(name, PERMIT_TLS_ALL_CLIENTCERTS) == 0) {
status = permit_tls_clientcerts(state, 1);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_CLIENT,
state->namaddr, NO_PRINT_ARGS);
} else if (strcasecmp(name, PERMIT_TLS_CLIENTCERTS) == 0) {
status = permit_tls_clientcerts(state, 0);
if (status == SMTPD_CHECK_OK)
status = smtpd_acl_permit(state, name, SMTPD_NAME_CLIENT,
state->namaddr, NO_PRINT_ARGS);
} else if (strcasecmp(name, REJECT_UNKNOWN_RCPTDOM) == 0) {
if (state->recipient)
status = reject_unknown_address(state, state->recipient,
state->recipient, SMTPD_NAME_RECIPIENT);
} else if (strcasecmp(name, REJECT_NON_FQDN_RCPT) == 0) {
if (state->recipient)
status = reject_non_fqdn_address(state, state->recipient,
state->recipient, SMTPD_NAME_RECIPIENT);
} else if (is_map_command(state, name, CHECK_RECIP_NS_ACL, &cpp)) {
if (state->recipient && *state->recipient) {
status = check_server_access(state, *cpp, state->recipient,
T_NS, state->recipient,
SMTPD_NAME_RECIPIENT, def_acl);
forbid_whitelist(state, name, status, state->recipient);
}
} else if (is_map_command(state, name, CHECK_RECIP_MX_ACL, &cpp)) {
if (state->recipient && *state->recipient) {
status = check_server_access(state, *cpp, state->recipient,
T_MX, state->recipient,
SMTPD_NAME_RECIPIENT, def_acl);
forbid_whitelist(state, name, status, state->recipient);
}
} else if (is_map_command(state, name, CHECK_RECIP_A_ACL, &cpp)) {
if (state->recipient && *state->recipient) {
status = check_server_access(state, *cpp, state->recipient,
T_A, state->recipient,
SMTPD_NAME_RECIPIENT, def_acl);
forbid_whitelist(state, name, status, state->recipient);
}
} else if (strcasecmp(name, REJECT_RHSBL_RECIPIENT) == 0) {
if (cpp[1] == 0)
msg_warn("restriction %s requires domain name argument", name);
else {
cpp += 1;
if (state->recipient)
status = reject_rbl_domain(state, *cpp, state->recipient,
SMTPD_NAME_RECIPIENT);
}
} else if (strcasecmp(name, CHECK_RCPT_MAPS) == 0
|| strcasecmp(name, REJECT_UNLISTED_RCPT) == 0) {
if (state->recipient && *state->recipient)
status = check_recipient_rcpt_maps(state, state->recipient);
} else if (strcasecmp(name, REJECT_MUL_RCPT_BOUNCE) == 0) {
if (state->sender && *state->sender == 0 && state->rcpt_count
> (strcmp(state->where, SMTPD_CMD_DATA) ? 0 : 1))
status = smtpd_check_reject(state, MAIL_ERROR_POLICY,
var_mul_rcpt_code, "5.5.3",
"<%s>: %s rejected: Multi-recipient bounce",
reply_name, reply_class);
} else if (strcasecmp(name, REJECT_UNVERIFIED_RECIP) == 0) {
if (state->recipient && *state->recipient)
status = reject_unverified_address(state, state->recipient,
state->recipient, SMTPD_NAME_RECIPIENT,
var_unv_rcpt_dcode, var_unv_rcpt_rcode,
unv_rcpt_tf_act,
var_unv_rcpt_why);
}
/*
* ETRN domain name restrictions.
*/
else if (is_map_command(state, name, CHECK_ETRN_ACL, &cpp)) {
if (state->etrn_name)
status = check_domain_access(state, *cpp, state->etrn_name,
FULL, &found, state->etrn_name,
SMTPD_NAME_ETRN, def_acl);
}
/*
* User-defined restriction class.
*/
else if ((list = (ARGV *) htable_find(smtpd_rest_classes, name)) != 0) {
status = generic_checks(state, list, reply_name,
reply_class, def_acl);
}
/*
* Error: undefined restriction name.
*/
else {
msg_warn("unknown smtpd restriction: \"%s\"", name);
reject_server_error(state);
}
if (msg_verbose)
msg_info("%s: name=%s status=%d", myname, name, status);
if (status < 0) {
if (status == DICT_ERR_RETRY)
reject_dict_retry(state, reply_name);
else
reject_server_error(state);
}
if (state->warn_if_reject >= state->recursion)
state->warn_if_reject = 0;
if (status != 0)
break;
if (state->defer_if_permit.active && state->defer_if_reject.active)
break;
}
if (msg_verbose)
msg_info(">>> END %s RESTRICTIONS <<<", reply_class);
state->recursion = saved_recursion;
/* In case the list terminated with one or more warn_if_mumble. */
if (state->warn_if_reject >= state->recursion)
state->warn_if_reject = 0;
return (status);
}
/* smtpd_check_addr - address sanity check */
int smtpd_check_addr(const char *sender, const char *addr, int smtputf8)
{
const RESOLVE_REPLY *resolve_reply;
const char *myname = "smtpd_check_addr";
const char *domain;
if (msg_verbose)
msg_info("%s: addr=%s", myname, addr);
/*
* Catch syntax errors early on if we can, but be prepared to re-compute
* the result later when the cache fills up with lots of recipients, at
* which time errors can still happen.
*/
if (addr == 0 || *addr == 0)
return (0);
resolve_reply = smtpd_resolve_addr(sender, addr);
if (resolve_reply->flags & RESOLVE_FLAG_ERROR)
return (-1);
/*
* Backwards compatibility: if the client does not request SMTPUTF8
* support, then behave like Postfix < 3.0 trivial-rewrite, and don't
* allow non-ASCII email domains. Historically, Postfix does not reject
* UTF8 etc. in the address localpart.
*/
if (smtputf8 == 0
&& (domain = strrchr(STR(resolve_reply->recipient), '@')) != 0
&& *(domain += 1) != 0 && !allascii(domain))
return (-1);
return (0);
}
/* smtpd_check_rewrite - choose address qualification context */
char *smtpd_check_rewrite(SMTPD_STATE *state)
{
const char *myname = "smtpd_check_rewrite";
int status;
char **cpp;
MAPS *maps;
char *name;
/*
* We don't use generic_checks() because it produces results that aren't
* applicable such as DEFER or REJECT.
*/
for (cpp = local_rewrite_clients->argv; *cpp != 0; cpp++) {
if (msg_verbose)
msg_info("%s: trying: %s", myname, *cpp);
status = SMTPD_CHECK_DUNNO;
if (strchr(name = *cpp, ':') != 0) {
name = CHECK_ADDR_MAP;
cpp -= 1;
}
if (strcasecmp(name, PERMIT_INET_INTERFACES) == 0) {
status = permit_inet_interfaces(state);
} else if (strcasecmp(name, PERMIT_MYNETWORKS) == 0) {
status = permit_mynetworks(state);
} else if (is_map_command(state, name, CHECK_ADDR_MAP, &cpp)) {
if ((maps = (MAPS *) htable_find(map_command_table, *cpp)) == 0)
msg_panic("%s: dictionary not found: %s", myname, *cpp);
if (maps_find(maps, state->addr, 0) != 0)
status = SMTPD_CHECK_OK;
else if (maps->error != 0) {
/* Warning is already logged. */
status = maps->error;
}
} else if (strcasecmp(name, PERMIT_SASL_AUTH) == 0) {
#ifdef USE_SASL_AUTH
if (smtpd_sasl_is_active(state))
status = permit_sasl_auth(state, SMTPD_CHECK_OK,
SMTPD_CHECK_DUNNO);
#endif
} else if (strcasecmp(name, PERMIT_TLS_ALL_CLIENTCERTS) == 0) {
status = permit_tls_clientcerts(state, 1);
} else if (strcasecmp(name, PERMIT_TLS_CLIENTCERTS) == 0) {
status = permit_tls_clientcerts(state, 0);
} else {
msg_warn("parameter %s: invalid request: %s",
VAR_LOC_RWR_CLIENTS, name);
continue;
}
if (status < 0) {
if (status == DICT_ERR_RETRY) {
state->error_mask |= MAIL_ERROR_RESOURCE;
log_whatsup(state, "reject",
"451 4.3.0 Temporary lookup error");
return ("451 4.3.0 Temporary lookup error");
} else {
state->error_mask |= MAIL_ERROR_SOFTWARE;
log_whatsup(state, "reject",
"451 4.3.5 Server configuration error");
return ("451 4.3.5 Server configuration error");
}
}
if (status == SMTPD_CHECK_OK) {
state->rewrite_context = MAIL_ATTR_RWR_LOCAL;
return (0);
}
}
state->rewrite_context = MAIL_ATTR_RWR_REMOTE;
return (0);
}
/* smtpd_check_client - validate client name or address */
char *smtpd_check_client(SMTPD_STATE *state)
{
int status;
/*
* Initialize.
*/
if (state->name == 0 || state->addr == 0)
return (0);
#define SMTPD_CHECK_RESET() { \
state->recursion = 0; \
state->warn_if_reject = 0; \
state->defer_if_reject.active = 0; \
}
/*
* Reset the defer_if_permit flag.
*/
state->defer_if_permit.active = 0;
/*
* Apply restrictions in the order as specified.
*/
SMTPD_CHECK_RESET();
status = setjmp(smtpd_check_buf);
if (status == 0 && client_restrctions->argc)
status = generic_checks(state, client_restrctions, state->namaddr,
SMTPD_NAME_CLIENT, CHECK_CLIENT_ACL);
state->defer_if_permit_client = state->defer_if_permit.active;
return (status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
}
/* smtpd_check_helo - validate HELO hostname */
char *smtpd_check_helo(SMTPD_STATE *state, char *helohost)
{
int status;
char *saved_helo;
/*
* Initialize.
*/
if (helohost == 0)
return (0);
/*
* Minor kluge so that we can delegate work to the generic routine and so
* that we can syslog the recipient with the reject messages.
*/
#define SMTPD_CHECK_PUSH(backup, current, new) { \
backup = current; \
current = (new ? mystrdup(new) : 0); \
}
#define SMTPD_CHECK_POP(current, backup) { \
if (current) myfree(current); \
current = backup; \
}
SMTPD_CHECK_PUSH(saved_helo, state->helo_name, helohost);
#define SMTPD_CHECK_HELO_RETURN(x) { \
SMTPD_CHECK_POP(state->helo_name, saved_helo); \
return (x); \
}
/*
* Restore the defer_if_permit flag to its value before HELO/EHLO, and do
* not set the flag when it was already raised by a previous protocol
* stage.
*/
state->defer_if_permit.active = state->defer_if_permit_client;
/*
* Apply restrictions in the order as specified.
*/
SMTPD_CHECK_RESET();
status = setjmp(smtpd_check_buf);
if (status == 0 && helo_restrctions->argc)
status = generic_checks(state, helo_restrctions, state->helo_name,
SMTPD_NAME_HELO, CHECK_HELO_ACL);
state->defer_if_permit_helo = state->defer_if_permit.active;
SMTPD_CHECK_HELO_RETURN(status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
}
/* smtpd_check_mail - validate sender address, driver */
char *smtpd_check_mail(SMTPD_STATE *state, char *sender)
{
int status;
char *saved_sender;
/*
* Initialize.
*/
if (sender == 0)
return (0);
/*
* Minor kluge so that we can delegate work to the generic routine and so
* that we can syslog the recipient with the reject messages.
*/
SMTPD_CHECK_PUSH(saved_sender, state->sender, sender);
#define SMTPD_CHECK_MAIL_RETURN(x) { \
SMTPD_CHECK_POP(state->sender, saved_sender); \
return (x); \
}
/*
* Restore the defer_if_permit flag to its value before MAIL FROM, and do
* not set the flag when it was already raised by a previous protocol
* stage. The client may skip the helo/ehlo.
*/
state->defer_if_permit.active = state->defer_if_permit_client
| state->defer_if_permit_helo;
state->sender_rcptmap_checked = 0;
/*
* Apply restrictions in the order as specified.
*/
SMTPD_CHECK_RESET();
status = setjmp(smtpd_check_buf);
if (status == 0 && mail_restrctions->argc)
status = generic_checks(state, mail_restrctions, sender,
SMTPD_NAME_SENDER, CHECK_SENDER_ACL);
state->defer_if_permit_sender = state->defer_if_permit.active;
/*
* If the "reject_unlisted_sender" restriction still needs to be applied,
* validate the sender here.
*/
if (var_smtpd_rej_unl_from
&& status != SMTPD_CHECK_REJECT && state->sender_rcptmap_checked == 0
&& state->discard == 0 && *sender)
status = check_sender_rcpt_maps(state, sender);
SMTPD_CHECK_MAIL_RETURN(status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
}
/* smtpd_check_rcpt - validate recipient address, driver */
char *smtpd_check_rcpt(SMTPD_STATE *state, char *recipient)
{
int status;
char *saved_recipient;
char *err;
ARGV *restrctions[2];
int n;
/*
* Initialize.
*/
if (recipient == 0)
return (0);
/*
* XXX 2821: Section 3.6 requires that "postmaster" be accepted even when
* specified without a fully qualified domain name.
*/
if (strcasecmp(recipient, "postmaster") == 0)
return (0);
/*
* Minor kluge so that we can delegate work to the generic routine and so
* that we can syslog the recipient with the reject messages.
*/
SMTPD_CHECK_PUSH(saved_recipient, state->recipient, recipient);
#define SMTPD_CHECK_RCPT_RETURN(x) { \
SMTPD_CHECK_POP(state->recipient, saved_recipient); \
return (x); \
}
/*
* The "check_recipient_maps" restriction is relevant only when
* responding to RCPT TO or VRFY.
*/
state->recipient_rcptmap_checked = 0;
/*
* Apply delayed restrictions.
*/
if (var_smtpd_delay_reject)
if ((err = smtpd_check_client(state)) != 0
|| (err = smtpd_check_helo(state, state->helo_name)) != 0
|| (err = smtpd_check_mail(state, state->sender)) != 0)
SMTPD_CHECK_RCPT_RETURN(err);
/*
* Restore the defer_if_permit flag to its value before RCPT TO, and do
* not set the flag when it was already raised by a previous protocol
* stage.
*/
state->defer_if_permit.active = state->defer_if_permit_sender;
/*
* Apply restrictions in the order as specified. We allow relay
* restrictions to be empty, for sites that require backwards
* compatibility.
*/
SMTPD_CHECK_RESET();
restrctions[0] = relay_restrctions;
restrctions[1] = rcpt_restrctions;
for (n = 0; n < 2; n++) {
status = setjmp(smtpd_check_buf);
if (status == 0 && restrctions[n]->argc)
status = generic_checks(state, restrctions[n],
recipient, SMTPD_NAME_RECIPIENT, CHECK_RECIP_ACL);
if (status == SMTPD_CHECK_REJECT)
break;
}
/*
* Force permission into deferral when some earlier temporary error may
* have prevented us from rejecting mail, and report the earlier problem.
*/
if (status != SMTPD_CHECK_REJECT && state->defer_if_permit.active)
status = smtpd_check_reject(state, state->defer_if_permit.class,
state->defer_if_permit.code,
STR(state->defer_if_permit.dsn),
"%s", STR(state->defer_if_permit.reason));
/*
* If the "reject_unlisted_recipient" restriction still needs to be
* applied, validate the recipient here.
*/
if (var_smtpd_rej_unl_rcpt
&& status != SMTPD_CHECK_REJECT
&& state->recipient_rcptmap_checked == 0
&& state->discard == 0)
status = check_recipient_rcpt_maps(state, recipient);
SMTPD_CHECK_RCPT_RETURN(status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
}
/* smtpd_check_etrn - validate ETRN request */
char *smtpd_check_etrn(SMTPD_STATE *state, char *domain)
{
int status;
char *saved_etrn_name;
char *err;
/*
* Initialize.
*/
if (domain == 0)
return (0);
/*
* Minor kluge so that we can delegate work to the generic routine and so
* that we can syslog the recipient with the reject messages.
*/
SMTPD_CHECK_PUSH(saved_etrn_name, state->etrn_name, domain);
#define SMTPD_CHECK_ETRN_RETURN(x) { \
SMTPD_CHECK_POP(state->etrn_name, saved_etrn_name); \
return (x); \
}
/*
* Apply delayed restrictions.
*/
if (var_smtpd_delay_reject)
if ((err = smtpd_check_client(state)) != 0
|| (err = smtpd_check_helo(state, state->helo_name)) != 0)
SMTPD_CHECK_ETRN_RETURN(err);
/*
* Restore the defer_if_permit flag to its value before ETRN, and do not
* set the flag when it was already raised by a previous protocol stage.
* The client may skip the helo/ehlo.
*/
state->defer_if_permit.active = state->defer_if_permit_client
| state->defer_if_permit_helo;
/*
* Apply restrictions in the order as specified.
*/
SMTPD_CHECK_RESET();
status = setjmp(smtpd_check_buf);
if (status == 0 && etrn_restrctions->argc)
status = generic_checks(state, etrn_restrctions, domain,
SMTPD_NAME_ETRN, CHECK_ETRN_ACL);
/*
* Force permission into deferral when some earlier temporary error may
* have prevented us from rejecting mail, and report the earlier problem.
*/
if (status != SMTPD_CHECK_REJECT && state->defer_if_permit.active)
status = smtpd_check_reject(state, state->defer_if_permit.class,
state->defer_if_permit.code,
STR(state->defer_if_permit.dsn),
"%s", STR(state->defer_if_permit.reason));
SMTPD_CHECK_ETRN_RETURN(status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
}
/* check_recipient_rcpt_maps - generic_checks() recipient table check */
static int check_recipient_rcpt_maps(SMTPD_STATE *state, const char *recipient)
{
/*
* Duplicate suppression. There's an implicit check_recipient_maps
* restriction at the end of all recipient restrictions.
*/
if (smtpd_input_transp_mask & INPUT_TRANSP_UNKNOWN_RCPT)
return (0);
if (state->recipient_rcptmap_checked == 1)
return (0);
if (state->warn_if_reject == 0)
/* We really validate the recipient address. */
state->recipient_rcptmap_checked = 1;
return (check_rcpt_maps(state, state->sender, recipient,
SMTPD_NAME_RECIPIENT));
}
/* check_sender_rcpt_maps - generic_checks() sender table check */
static int check_sender_rcpt_maps(SMTPD_STATE *state, const char *sender)
{
/*
* Duplicate suppression. There's an implicit check_sender_maps
* restriction at the end of all sender restrictions.
*/
if (smtpd_input_transp_mask & INPUT_TRANSP_UNKNOWN_RCPT)
return (0);
if (state->sender_rcptmap_checked == 1)
return (0);
if (state->warn_if_reject == 0)
/* We really validate the sender address. */
state->sender_rcptmap_checked = 1;
return (check_rcpt_maps(state, state->recipient, sender,
SMTPD_NAME_SENDER));
}
/* check_rcpt_maps - generic_checks() interface for recipient table check */
static int check_rcpt_maps(SMTPD_STATE *state, const char *sender,
const char *recipient,
const char *reply_class)
{
const RESOLVE_REPLY *reply;
DSN_SPLIT dp;
if (msg_verbose)
msg_info(">>> CHECKING %s VALIDATION MAPS <<<", reply_class);
/*
* Resolve the address.
*/
reply = smtpd_resolve_addr(sender, recipient);
if (reply->flags & RESOLVE_FLAG_FAIL)
reject_dict_retry(state, recipient);
/*
* Make complex expressions more readable?
*/
#define MATCH(map, rcpt) \
check_mail_addr_find(state, recipient, map, rcpt, (char **) 0)
#define NOMATCH(map, rcpt) (MATCH(map, rcpt) == 0)
/*
* XXX We assume the recipient address is OK if it matches a canonical
* map or virtual alias map. Eventually, the address resolver should give
* us the final resolved recipient address, and the SMTP server should
* write the final resolved recipient address to the output record
* stream. See also the next comment block on recipients in virtual alias
* domains.
*/
if (MATCH(rcpt_canon_maps, CONST_STR(reply->recipient))
|| (strcmp(reply_class, SMTPD_NAME_SENDER) == 0
&& MATCH(send_canon_maps, CONST_STR(reply->recipient)))
|| MATCH(canonical_maps, CONST_STR(reply->recipient))
|| MATCH(virt_alias_maps, CONST_STR(reply->recipient)))
return (0);
/*
* At this point, anything that resolves to the error mailer is known to
* be undeliverable.
*
* XXX Until the address resolver does final address resolution, known and
* unknown recipients in virtual alias domains will both resolve to
* "error:user unknown".
*/
if (strcmp(STR(reply->transport), MAIL_SERVICE_ERROR) == 0) {
dsn_split(&dp, strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
"5.1.0" : "5.1.1", STR(reply->nexthop));
return (smtpd_check_reject(state, MAIL_ERROR_BOUNCE,
(reply->flags & RESOLVE_CLASS_ALIAS) ?
var_virt_alias_code : 550,
smtpd_dsn_fix(DSN_STATUS(dp.dsn),
reply_class),
"<%s>: %s rejected: %s",
recipient, reply_class,
dp.text));
}
if (strcmp(STR(reply->transport), MAIL_SERVICE_RETRY) == 0) {
dsn_split(&dp, strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
"4.1.0" : "4.1.1", STR(reply->nexthop));
return (smtpd_check_reject(state, MAIL_ERROR_BOUNCE, 450,
smtpd_dsn_fix(DSN_STATUS(dp.dsn),
reply_class),
"<%s>: %s rejected: %s",
recipient, reply_class,
dp.text));
}
/*
* Search the recipient lookup tables of the respective address class.
*
* XXX Use the less expensive maps_find() (built-in case folding) instead of
* the baroque mail_addr_find(). But then we have to strip the domain and
* deal with address extensions ourselves.
*
* XXX But that would break sites that use the virtual delivery agent for
* local delivery, because the virtual delivery agent requires
* user@domain style addresses in its user database.
*/
#define MATCH_LEFT(l, r, n) \
(strncasecmp_utf8((l), (r), (n)) == 0 && (r)[n] == '@')
switch (reply->flags & RESOLVE_CLASS_MASK) {
/*
* Reject mail to unknown addresses in local domains (domains that
* match $mydestination or ${proxy,inet}_interfaces).
*/
case RESOLVE_CLASS_LOCAL:
if (*var_local_rcpt_maps
/* Generated by bounce, absorbed by qmgr. */
&& !MATCH_LEFT(var_double_bounce_sender, CONST_STR(reply->recipient),
strlen(var_double_bounce_sender))
/* Absorbed by qmgr. */
&& !MATCH_LEFT(MAIL_ADDR_POSTMASTER, CONST_STR(reply->recipient),
strlen(MAIL_ADDR_POSTMASTER))
/* Generated by bounce. */
&& !MATCH_LEFT(MAIL_ADDR_MAIL_DAEMON, CONST_STR(reply->recipient),
strlen(MAIL_ADDR_MAIL_DAEMON))
&& NOMATCH(local_rcpt_maps, CONST_STR(reply->recipient)))
return (smtpd_check_reject(state, MAIL_ERROR_BOUNCE,
var_local_rcpt_code,
strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
"5.1.0" : "5.1.1",
"<%s>: %s rejected: User unknown%s",
recipient, reply_class,
var_show_unk_rcpt_table ?
" in local recipient table" : ""));
break;
/*
* Reject mail to unknown addresses in virtual mailbox domains.
*/
case RESOLVE_CLASS_VIRTUAL:
if (*var_virt_mailbox_maps
&& NOMATCH(virt_mailbox_maps, CONST_STR(reply->recipient)))
return (smtpd_check_reject(state, MAIL_ERROR_BOUNCE,
var_virt_mailbox_code,
strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
"5.1.0" : "5.1.1",
"<%s>: %s rejected: User unknown%s",
recipient, reply_class,
var_show_unk_rcpt_table ?
" in virtual mailbox table" : ""));
break;
/*
* Reject mail to unknown addresses in relay domains.
*/
case RESOLVE_CLASS_RELAY:
if (*var_relay_rcpt_maps
&& NOMATCH(relay_rcpt_maps, CONST_STR(reply->recipient)))
return (smtpd_check_reject(state, MAIL_ERROR_BOUNCE,
var_relay_rcpt_code,
strcmp(reply_class, SMTPD_NAME_SENDER) == 0 ?
"5.1.0" : "5.1.1",
"<%s>: %s rejected: User unknown%s",
recipient, reply_class,
var_show_unk_rcpt_table ?
" in relay recipient table" : ""));
if (warn_compat_break_relay_domains)
msg_info("using backwards-compatible default setting "
VAR_RELAY_DOMAINS "=$mydestination to accept mail "
"for address \"%s\"", recipient);
break;
}
/*
* Accept all other addresses - including addresses that passed the above
* tests because of some table lookup problem.
*/
return (0);
}
/* smtpd_check_size - check optional SIZE parameter value */
char *smtpd_check_size(SMTPD_STATE *state, off_t size)
{
int status;
/*
* Return here in case of serious trouble.
*/
SMTPD_CHECK_RESET();
if ((status = setjmp(smtpd_check_buf)) != 0)
return (status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
/*
* Check against file size limit.
*/
if (var_message_limit > 0 && size > var_message_limit) {
(void) smtpd_check_reject(state, MAIL_ERROR_POLICY,
552, "5.3.4",
"Message size exceeds fixed limit");
return (STR(error_text));
}
return (0);
}
/* smtpd_check_queue - check queue space */
char *smtpd_check_queue(SMTPD_STATE *state)
{
const char *myname = "smtpd_check_queue";
struct fsspace fsbuf;
int status;
/*
* Return here in case of serious trouble.
*/
SMTPD_CHECK_RESET();
if ((status = setjmp(smtpd_check_buf)) != 0)
return (status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
/*
* Avoid overflow/underflow when comparing message size against available
* space.
*/
#define BLOCKS(x) ((x) / fsbuf.block_size)
fsspace(".", &fsbuf);
if (msg_verbose)
msg_info("%s: blocks %lu avail %lu min_free %lu msg_size_limit %lu",
myname,
(unsigned long) fsbuf.block_size,
(unsigned long) fsbuf.block_free,
(unsigned long) var_queue_minfree,
(unsigned long) var_message_limit);
if (BLOCKS(var_queue_minfree) >= fsbuf.block_free
|| BLOCKS(var_message_limit) >= fsbuf.block_free / smtpd_space_multf) {
(void) smtpd_check_reject(state, MAIL_ERROR_RESOURCE,
452, "4.3.1",
"Insufficient system storage");
msg_warn("not enough free space in mail queue: %lu bytes < "
"%g*message size limit",
(unsigned long) fsbuf.block_free * fsbuf.block_size,
smtpd_space_multf);
return (STR(error_text));
}
return (0);
}
/* smtpd_check_data - check DATA command */
char *smtpd_check_data(SMTPD_STATE *state)
{
int status;
char *NOCLOBBER saved_recipient;
/*
* Minor kluge so that we can delegate work to the generic routine. We
* provide no recipient information in the case of multiple recipients,
* This restriction applies to all recipients alike, and logging only one
* of them would be misleading.
*/
if (state->rcpt_count > 1) {
saved_recipient = state->recipient;
state->recipient = 0;
}
/*
* Reset the defer_if_permit flag. This is necessary when some recipients
* were accepted but the last one was rejected.
*/
state->defer_if_permit.active = 0;
/*
* Apply restrictions in the order as specified.
*
* XXX We cannot specify a default target for a bare access map.
*/
SMTPD_CHECK_RESET();
status = setjmp(smtpd_check_buf);
if (status == 0 && data_restrctions->argc)
status = generic_checks(state, data_restrctions,
SMTPD_CMD_DATA, SMTPD_NAME_DATA, NO_DEF_ACL);
/*
* Force permission into deferral when some earlier temporary error may
* have prevented us from rejecting mail, and report the earlier problem.
*/
if (status != SMTPD_CHECK_REJECT && state->defer_if_permit.active)
status = smtpd_check_reject(state, state->defer_if_permit.class,
state->defer_if_permit.code,
STR(state->defer_if_permit.dsn),
"%s", STR(state->defer_if_permit.reason));
if (state->rcpt_count > 1)
state->recipient = saved_recipient;
return (status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
}
/* smtpd_check_eod - check end-of-data command */
char *smtpd_check_eod(SMTPD_STATE *state)
{
int status;
char *NOCLOBBER saved_recipient;
/*
* Minor kluge so that we can delegate work to the generic routine. We
* provide no recipient information in the case of multiple recipients,
* This restriction applies to all recipients alike, and logging only one
* of them would be misleading.
*/
if (state->rcpt_count > 1) {
saved_recipient = state->recipient;
state->recipient = 0;
}
/*
* Reset the defer_if_permit flag. This is necessary when some recipients
* were accepted but the last one was rejected.
*/
state->defer_if_permit.active = 0;
/*
* Apply restrictions in the order as specified.
*
* XXX We cannot specify a default target for a bare access map.
*/
SMTPD_CHECK_RESET();
status = setjmp(smtpd_check_buf);
if (status == 0 && eod_restrictions->argc)
status = generic_checks(state, eod_restrictions,
SMTPD_CMD_EOD, SMTPD_NAME_EOD, NO_DEF_ACL);
/*
* Force permission into deferral when some earlier temporary error may
* have prevented us from rejecting mail, and report the earlier problem.
*/
if (status != SMTPD_CHECK_REJECT && state->defer_if_permit.active)
status = smtpd_check_reject(state, state->defer_if_permit.class,
state->defer_if_permit.code,
STR(state->defer_if_permit.dsn),
"%s", STR(state->defer_if_permit.reason));
if (state->rcpt_count > 1)
state->recipient = saved_recipient;
return (status == SMTPD_CHECK_REJECT ? STR(error_text) : 0);
}
#ifdef TEST
/*
* Test program to try out all these restrictions without having to go live.
* This is not entirely stand-alone, as it requires access to the Postfix
* rewrite/resolve service. This is just for testing code, not for debugging
* configuration files.
*/
#include <stdlib.h>
#include <msg_vstream.h>
#include <vstring_vstream.h>
#include <mail_conf.h>
#include <rewrite_clnt.h>
#include <dns.h>
#include <smtpd_chat.h>
int smtpd_input_transp_mask;
/*
* Dummies. These are never set.
*/
char *var_client_checks = "";
char *var_helo_checks = "";
char *var_mail_checks = "";
char *var_relay_checks = "";
char *var_rcpt_checks = "";
char *var_etrn_checks = "";
char *var_data_checks = "";
char *var_eod_checks = "";
char *var_relay_domains = "";
char *var_smtpd_uproxy_proto = "";
int var_smtpd_uproxy_tmout = 0;
#ifdef USE_TLS
char *var_relay_ccerts = "";
#endif
char *var_mynetworks = "";
char *var_notify_classes = "";
char *var_smtpd_policy_def_action = "";
char *var_smtpd_policy_context = "";
/*
* String-valued configuration parameters.
*/
char *var_maps_rbl_domains;
char *var_myorigin;
char *var_mydest;
char *var_inet_interfaces;
char *var_proxy_interfaces;
char *var_rcpt_delim;
char *var_rest_classes;
char *var_alias_maps;
char *var_send_canon_maps;
char *var_rcpt_canon_maps;
char *var_canonical_maps;
char *var_virt_alias_maps;
char *var_virt_alias_doms;
char *var_virt_mailbox_maps;
char *var_virt_mailbox_doms;
char *var_local_rcpt_maps;
char *var_perm_mx_networks;
char *var_par_dom_match;
char *var_smtpd_null_key;
char *var_smtpd_snd_auth_maps;
char *var_double_bounce_sender;
char *var_rbl_reply_maps;
char *var_smtpd_exp_filter;
char *var_def_rbl_reply;
char *var_relay_rcpt_maps;
char *var_verify_sender;
char *var_smtpd_sasl_opts;
char *var_local_rwr_clients;
char *var_smtpd_relay_ccerts;
char *var_unv_from_why;
char *var_unv_rcpt_why;
char *var_stress;
char *var_unk_name_tf_act;
char *var_unk_addr_tf_act;
char *var_unv_rcpt_tf_act;
char *var_unv_from_tf_act;
char *var_smtpd_acl_perm_log;
typedef struct {
char *name;
char *defval;
char **target;
} STRING_TABLE;
#undef DEF_VIRT_ALIAS_MAPS
#define DEF_VIRT_ALIAS_MAPS ""
#undef DEF_LOCAL_RCPT_MAPS
#define DEF_LOCAL_RCPT_MAPS ""
static const STRING_TABLE string_table[] = {
VAR_MAPS_RBL_DOMAINS, DEF_MAPS_RBL_DOMAINS, &var_maps_rbl_domains,
VAR_MYORIGIN, DEF_MYORIGIN, &var_myorigin,
VAR_MYDEST, DEF_MYDEST, &var_mydest,
VAR_INET_INTERFACES, DEF_INET_INTERFACES, &var_inet_interfaces,
VAR_PROXY_INTERFACES, DEF_PROXY_INTERFACES, &var_proxy_interfaces,
VAR_RCPT_DELIM, DEF_RCPT_DELIM, &var_rcpt_delim,
VAR_REST_CLASSES, DEF_REST_CLASSES, &var_rest_classes,
VAR_ALIAS_MAPS, DEF_ALIAS_MAPS, &var_alias_maps,
VAR_SEND_CANON_MAPS, DEF_SEND_CANON_MAPS, &var_send_canon_maps,
VAR_RCPT_CANON_MAPS, DEF_RCPT_CANON_MAPS, &var_rcpt_canon_maps,
VAR_CANONICAL_MAPS, DEF_CANONICAL_MAPS, &var_canonical_maps,
VAR_VIRT_ALIAS_MAPS, DEF_VIRT_ALIAS_MAPS, &var_virt_alias_maps,
VAR_VIRT_ALIAS_DOMS, DEF_VIRT_ALIAS_DOMS, &var_virt_alias_doms,
VAR_VIRT_MAILBOX_MAPS, DEF_VIRT_MAILBOX_MAPS, &var_virt_mailbox_maps,
VAR_VIRT_MAILBOX_DOMS, DEF_VIRT_MAILBOX_DOMS, &var_virt_mailbox_doms,
VAR_LOCAL_RCPT_MAPS, DEF_LOCAL_RCPT_MAPS, &var_local_rcpt_maps,
VAR_PERM_MX_NETWORKS, DEF_PERM_MX_NETWORKS, &var_perm_mx_networks,
VAR_PAR_DOM_MATCH, DEF_PAR_DOM_MATCH, &var_par_dom_match,
VAR_SMTPD_SND_AUTH_MAPS, DEF_SMTPD_SND_AUTH_MAPS, &var_smtpd_snd_auth_maps,
VAR_SMTPD_NULL_KEY, DEF_SMTPD_NULL_KEY, &var_smtpd_null_key,
VAR_DOUBLE_BOUNCE, DEF_DOUBLE_BOUNCE, &var_double_bounce_sender,
VAR_RBL_REPLY_MAPS, DEF_RBL_REPLY_MAPS, &var_rbl_reply_maps,
VAR_SMTPD_EXP_FILTER, DEF_SMTPD_EXP_FILTER, &var_smtpd_exp_filter,
VAR_DEF_RBL_REPLY, DEF_DEF_RBL_REPLY, &var_def_rbl_reply,
VAR_RELAY_RCPT_MAPS, DEF_RELAY_RCPT_MAPS, &var_relay_rcpt_maps,
VAR_VERIFY_SENDER, DEF_VERIFY_SENDER, &var_verify_sender,
VAR_MAIL_NAME, DEF_MAIL_NAME, &var_mail_name,
VAR_SMTPD_SASL_OPTS, DEF_SMTPD_SASL_OPTS, &var_smtpd_sasl_opts,
VAR_LOC_RWR_CLIENTS, DEF_LOC_RWR_CLIENTS, &var_local_rwr_clients,
VAR_RELAY_CCERTS, DEF_RELAY_CCERTS, &var_smtpd_relay_ccerts,
VAR_UNV_FROM_WHY, DEF_UNV_FROM_WHY, &var_unv_from_why,
VAR_UNV_RCPT_WHY, DEF_UNV_RCPT_WHY, &var_unv_rcpt_why,
VAR_STRESS, DEF_STRESS, &var_stress,
/* XXX Can't use ``$name'' type default values below. */
VAR_UNK_NAME_TF_ACT, DEF_REJECT_TMPF_ACT, &var_unk_name_tf_act,
VAR_UNK_ADDR_TF_ACT, DEF_REJECT_TMPF_ACT, &var_unk_addr_tf_act,
VAR_UNV_RCPT_TF_ACT, DEF_REJECT_TMPF_ACT, &var_unv_rcpt_tf_act,
VAR_UNV_FROM_TF_ACT, DEF_REJECT_TMPF_ACT, &var_unv_from_tf_act,
/* XXX Can't use ``$name'' type default values above. */
VAR_SMTPD_ACL_PERM_LOG, DEF_SMTPD_ACL_PERM_LOG, &var_smtpd_acl_perm_log,
VAR_SMTPD_DNS_RE_FILTER, DEF_SMTPD_DNS_RE_FILTER, &var_smtpd_dns_re_filter,
0,
};
/* string_init - initialize string parameters */
static void string_init(void)
{
const STRING_TABLE *sp;
for (sp = string_table; sp->name; sp++)
sp->target[0] = mystrdup(sp->defval);
}
/* string_update - update string parameter */
static int string_update(char **argv)
{
const STRING_TABLE *sp;
for (sp = string_table; sp->name; sp++) {
if (strcasecmp(argv[0], sp->name) == 0) {
myfree(sp->target[0]);
sp->target[0] = mystrdup(argv[1]);
return (1);
}
}
return (0);
}
/*
* Integer parameters.
*/
int var_queue_minfree; /* XXX use off_t */
typedef struct {
char *name;
int defval;
int *target;
} INT_TABLE;
int var_unk_client_code;
int var_bad_name_code;
int var_unk_name_code;
int var_unk_addr_code;
int var_relay_code;
int var_maps_rbl_code;
int var_map_reject_code;
int var_map_defer_code;
int var_reject_code;
int var_defer_code;
int var_non_fqdn_code;
int var_smtpd_delay_reject;
int var_allow_untrust_route;
int var_mul_rcpt_code;
int var_unv_from_rcode;
int var_unv_from_dcode;
int var_unv_rcpt_rcode;
int var_unv_rcpt_dcode;
int var_local_rcpt_code;
int var_relay_rcpt_code;
int var_virt_mailbox_code;
int var_virt_alias_code;
int var_show_unk_rcpt_table;
int var_verify_poll_count;
int var_verify_poll_delay;
int var_smtpd_policy_tmout;
int var_smtpd_policy_idle;
int var_smtpd_policy_ttl;
int var_smtpd_policy_req_limit;
int var_smtpd_policy_try_limit;
int var_smtpd_policy_try_delay;
int var_smtpd_rej_unl_from;
int var_smtpd_rej_unl_rcpt;
int var_plaintext_code;
bool var_smtpd_peername_lookup;
bool var_smtpd_client_port_log;
char *var_smtpd_dns_re_filter;
#define int_table test_int_table
static const INT_TABLE int_table[] = {
"msg_verbose", 0, &msg_verbose,
VAR_UNK_CLIENT_CODE, DEF_UNK_CLIENT_CODE, &var_unk_client_code,
VAR_BAD_NAME_CODE, DEF_BAD_NAME_CODE, &var_bad_name_code,
VAR_UNK_NAME_CODE, DEF_UNK_NAME_CODE, &var_unk_name_code,
VAR_UNK_ADDR_CODE, DEF_UNK_ADDR_CODE, &var_unk_addr_code,
VAR_RELAY_CODE, DEF_RELAY_CODE, &var_relay_code,
VAR_MAPS_RBL_CODE, DEF_MAPS_RBL_CODE, &var_maps_rbl_code,
VAR_MAP_REJECT_CODE, DEF_MAP_REJECT_CODE, &var_map_reject_code,
VAR_MAP_DEFER_CODE, DEF_MAP_DEFER_CODE, &var_map_defer_code,
VAR_REJECT_CODE, DEF_REJECT_CODE, &var_reject_code,
VAR_DEFER_CODE, DEF_DEFER_CODE, &var_defer_code,
VAR_NON_FQDN_CODE, DEF_NON_FQDN_CODE, &var_non_fqdn_code,
VAR_SMTPD_DELAY_REJECT, DEF_SMTPD_DELAY_REJECT, &var_smtpd_delay_reject,
VAR_ALLOW_UNTRUST_ROUTE, DEF_ALLOW_UNTRUST_ROUTE, &var_allow_untrust_route,
VAR_MUL_RCPT_CODE, DEF_MUL_RCPT_CODE, &var_mul_rcpt_code,
VAR_UNV_FROM_RCODE, DEF_UNV_FROM_RCODE, &var_unv_from_rcode,
VAR_UNV_FROM_DCODE, DEF_UNV_FROM_DCODE, &var_unv_from_dcode,
VAR_UNV_RCPT_RCODE, DEF_UNV_RCPT_RCODE, &var_unv_rcpt_rcode,
VAR_UNV_RCPT_DCODE, DEF_UNV_RCPT_DCODE, &var_unv_rcpt_dcode,
VAR_LOCAL_RCPT_CODE, DEF_LOCAL_RCPT_CODE, &var_local_rcpt_code,
VAR_RELAY_RCPT_CODE, DEF_RELAY_RCPT_CODE, &var_relay_rcpt_code,
VAR_VIRT_ALIAS_CODE, DEF_VIRT_ALIAS_CODE, &var_virt_alias_code,
VAR_VIRT_MAILBOX_CODE, DEF_VIRT_MAILBOX_CODE, &var_virt_mailbox_code,
VAR_SHOW_UNK_RCPT_TABLE, DEF_SHOW_UNK_RCPT_TABLE, &var_show_unk_rcpt_table,
VAR_VERIFY_POLL_COUNT, 3, &var_verify_poll_count,
VAR_SMTPD_REJ_UNL_FROM, DEF_SMTPD_REJ_UNL_FROM, &var_smtpd_rej_unl_from,
VAR_SMTPD_REJ_UNL_RCPT, DEF_SMTPD_REJ_UNL_RCPT, &var_smtpd_rej_unl_rcpt,
VAR_PLAINTEXT_CODE, DEF_PLAINTEXT_CODE, &var_plaintext_code,
VAR_SMTPD_PEERNAME_LOOKUP, DEF_SMTPD_PEERNAME_LOOKUP, &var_smtpd_peername_lookup,
VAR_SMTPD_CLIENT_PORT_LOG, DEF_SMTPD_CLIENT_PORT_LOG, &var_smtpd_client_port_log,
0,
};
/* int_init - initialize int parameters */
static void int_init(void)
{
const INT_TABLE *sp;
for (sp = int_table; sp->name; sp++)
sp->target[0] = sp->defval;
}
/* int_update - update int parameter */
static int int_update(char **argv)
{
const INT_TABLE *ip;
for (ip = int_table; ip->name; ip++) {
if (strcasecmp(argv[0], ip->name) == 0) {
if (!ISDIGIT(*argv[1]))
msg_fatal("bad number: %s %s", ip->name, argv[1]);
ip->target[0] = atoi(argv[1]);
return (1);
}
}
return (0);
}
/*
* Restrictions.
*/
typedef struct {
char *name;
ARGV **target;
} REST_TABLE;
static const REST_TABLE rest_table[] = {
"client_restrictions", &client_restrctions,
"helo_restrictions", &helo_restrctions,
"sender_restrictions", &mail_restrctions,
"relay_restrictions", &relay_restrctions,
"recipient_restrictions", &rcpt_restrctions,
"etrn_restrictions", &etrn_restrctions,
0,
};
/* rest_update - update restriction */
static int rest_update(char **argv)
{
const REST_TABLE *rp;
for (rp = rest_table; rp->name; rp++) {
if (strcasecmp(rp->name, argv[0]) == 0) {
argv_free(rp->target[0]);
rp->target[0] = smtpd_check_parse(SMTPD_CHECK_PARSE_ALL, argv[1]);
return (1);
}
}
return (0);
}
/* rest_class - (re)define a restriction class */
static void rest_class(char *class)
{
char *cp = class;
char *name;
HTABLE_INFO *entry;
if (smtpd_rest_classes == 0)
smtpd_rest_classes = htable_create(1);
if ((name = mystrtok(&cp, CHARS_COMMA_SP)) == 0)
msg_panic("rest_class: null class name");
if ((entry = htable_locate(smtpd_rest_classes, name)) != 0)
argv_free((ARGV *) entry->value);
else
entry = htable_enter(smtpd_rest_classes, name, (void *) 0);
entry->value = (void *) smtpd_check_parse(SMTPD_CHECK_PARSE_ALL, cp);
}
/* resolve_clnt_init - initialize reply */
void resolve_clnt_init(RESOLVE_REPLY *reply)
{
reply->flags = 0;
reply->transport = vstring_alloc(100);
reply->nexthop = vstring_alloc(100);
reply->recipient = vstring_alloc(100);
}
void resolve_clnt_free(RESOLVE_REPLY *reply)
{
vstring_free(reply->transport);
vstring_free(reply->nexthop);
vstring_free(reply->recipient);
}
bool var_smtpd_sasl_enable = 0;
#ifdef USE_SASL_AUTH
/* smtpd_sasl_activate - stub */
void smtpd_sasl_activate(SMTPD_STATE *state, const char *opts_name,
const char *opts_var)
{
msg_panic("smtpd_sasl_activate was called");
}
/* smtpd_sasl_deactivate - stub */
void smtpd_sasl_deactivate(SMTPD_STATE *state)
{
msg_panic("smtpd_sasl_deactivate was called");
}
/* permit_sasl_auth - stub */
int permit_sasl_auth(SMTPD_STATE *state, int ifyes, int ifnot)
{
return (ifnot);
}
/* smtpd_sasl_state_init - the real deal */
void smtpd_sasl_state_init(SMTPD_STATE *state)
{
state->sasl_username = 0;
state->sasl_method = 0;
state->sasl_sender = 0;
}
#endif
/* verify_clnt_query - stub */
int verify_clnt_query(const char *addr, int *addr_status, VSTRING *why)
{
*addr_status = DEL_RCPT_STAT_OK;
return (VRFY_STAT_OK);
}
/* rewrite_clnt_internal - stub */
VSTRING *rewrite_clnt_internal(const char *context, const char *addr,
VSTRING *result)
{
if (addr == STR(result))
msg_panic("rewrite_clnt_internal: result clobbers input");
if (*addr && strchr(addr, '@') == 0)
msg_fatal("%s: address rewriting is disabled", addr);
vstring_strcpy(result, addr);
return (result);
}
/* resolve_clnt_query - stub */
void resolve_clnt(const char *class, const char *unused_sender, const char *addr,
RESOLVE_REPLY *reply)
{
const char *domain;
int rc;
if (addr == CONST_STR(reply->recipient))
msg_panic("resolve_clnt_query: result clobbers input");
if (strchr(addr, '%'))
msg_fatal("%s: address rewriting is disabled", addr);
if ((domain = strrchr(addr, '@')) == 0)
msg_fatal("%s: unqualified address", addr);
domain += 1;
if ((rc = resolve_local(domain)) > 0) {
reply->flags = RESOLVE_CLASS_LOCAL;
vstring_strcpy(reply->transport, MAIL_SERVICE_LOCAL);
vstring_strcpy(reply->nexthop, domain);
} else if (rc < 0) {
reply->flags = RESOLVE_FLAG_FAIL;
} else if (string_list_match(virt_alias_doms, domain)) {
reply->flags = RESOLVE_CLASS_ALIAS;
vstring_strcpy(reply->transport, MAIL_SERVICE_ERROR);
vstring_strcpy(reply->nexthop, "user unknown");
} else if (virt_alias_doms->error) {
reply->flags = RESOLVE_FLAG_FAIL;
} else if (string_list_match(virt_mailbox_doms, domain)) {
reply->flags = RESOLVE_CLASS_VIRTUAL;
vstring_strcpy(reply->transport, MAIL_SERVICE_VIRTUAL);
vstring_strcpy(reply->nexthop, domain);
} else if (virt_mailbox_doms->error) {
reply->flags = RESOLVE_FLAG_FAIL;
} else if (domain_list_match(relay_domains, domain)) {
reply->flags = RESOLVE_CLASS_RELAY;
vstring_strcpy(reply->transport, MAIL_SERVICE_RELAY);
vstring_strcpy(reply->nexthop, domain);
} else if (relay_domains->error) {
reply->flags = RESOLVE_FLAG_FAIL;
} else {
reply->flags = RESOLVE_CLASS_DEFAULT;
vstring_strcpy(reply->transport, MAIL_SERVICE_SMTP);
vstring_strcpy(reply->nexthop, domain);
}
vstring_strcpy(reply->recipient, addr);
}
/* smtpd_chat_reset - stub */
void smtpd_chat_reset(SMTPD_STATE *unused_state)
{
}
/* usage - scream and terminate */
static NORETURN usage(char *myname)
{
msg_fatal("usage: %s", myname);
}
int main(int argc, char **argv)
{
VSTRING *buf = vstring_alloc(100);
SMTPD_STATE state;
ARGV *args;
char *bp;
char *resp;
char *addr;
/*
* Initialization. Use dummies for client information.
*/
msg_vstream_init(argv[0], VSTREAM_ERR);
if (argc != 1)
usage(argv[0]);
string_init();
int_init();
smtpd_check_init();
smtpd_expand_init();
(void) inet_proto_init(argv[0], INET_PROTO_NAME_IPV4);
smtpd_state_init(&state, VSTREAM_IN, "smtpd");
state.queue_id = "<queue id>";
/*
* Main loop: update config parameters or test the client, helo, sender
* and recipient restrictions.
*/
while (vstring_fgets_nonl(buf, VSTREAM_IN) != 0) {
/*
* Tokenize the command. Note, the comma is not a separator, so that
* restriction lists can be entered as comma-separated lists.
*/
bp = STR(buf);
if (!isatty(0)) {
vstream_printf(">>> %s\n", bp);
vstream_fflush(VSTREAM_OUT);
}
if (*bp == '#')
continue;
if (*bp == '!') {
vstream_printf("exit %d\n", system(bp + 1));
continue;
}
args = argv_splitq(bp, CHARS_SPACE, CHARS_BRACE);
/*
* Recognize the command.
*/
resp = "bad command";
switch (args->argc) {
/*
* Emtpy line.
*/
case 0:
argv_free(args);
continue;
/*
* Special case: rewrite context.
*/
case 1:
if (strcasecmp(args->argv[0], "rewrite") == 0) {
resp = smtpd_check_rewrite(&state);
break;
}
/*
* Other parameter-less commands.
*/
if (strcasecmp(args->argv[0], "flush_dnsxl_cache") == 0) {
if (smtpd_rbl_cache) {
ctable_free(smtpd_rbl_cache);
ctable_free(smtpd_rbl_byte_cache);
}
smtpd_rbl_cache = ctable_create(100, rbl_pagein,
rbl_pageout, (void *) 0);
smtpd_rbl_byte_cache = ctable_create(1000, rbl_byte_pagein,
rbl_byte_pageout, (void *) 0);
resp = 0;
break;
}
/*
* Special case: client identity.
*/
case 4:
case 3:
if (strcasecmp(args->argv[0], "client") == 0) {
state.where = SMTPD_AFTER_CONNECT;
UPDATE_STRING(state.name, args->argv[1]);
UPDATE_STRING(state.reverse_name, args->argv[1]);
UPDATE_STRING(state.addr, args->argv[2]);
if (args->argc == 4)
state.name_status =
state.reverse_name_status =
atoi(args->argv[3]);
else if (strcmp(state.name, "unknown") == 0)
state.name_status =
state.reverse_name_status =
SMTPD_PEER_CODE_TEMP;
else
state.name_status =
state.reverse_name_status =
SMTPD_PEER_CODE_OK;
if (state.namaddr)
myfree(state.namaddr);
state.namaddr = concatenate(state.name, "[", state.addr,
"]", (char *) 0);
resp = smtpd_check_client(&state);
}
break;
/*
* Try config settings.
*/
#define UPDATE_MAPS(ptr, var, val, lock) \
{ if (ptr) maps_free(ptr); ptr = maps_create(var, val, lock); }
#define UPDATE_LIST(ptr, var, val) \
{ if (ptr) string_list_free(ptr); \
ptr = string_list_init(var, MATCH_FLAG_NONE, val); }
case 2:
if (strcasecmp(args->argv[0], VAR_MYDEST) == 0) {
UPDATE_STRING(var_mydest, args->argv[1]);
resolve_local_init();
smtpd_resolve_init(100);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_VIRT_ALIAS_MAPS) == 0) {
UPDATE_STRING(var_virt_alias_maps, args->argv[1]);
UPDATE_MAPS(virt_alias_maps, VAR_VIRT_ALIAS_MAPS,
var_virt_alias_maps, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX | DICT_FLAG_UTF8_REQUEST);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_VIRT_ALIAS_DOMS) == 0) {
UPDATE_STRING(var_virt_alias_doms, args->argv[1]);
UPDATE_LIST(virt_alias_doms, VAR_VIRT_ALIAS_DOMS,
var_virt_alias_doms);
smtpd_resolve_init(100);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_VIRT_MAILBOX_MAPS) == 0) {
UPDATE_STRING(var_virt_mailbox_maps, args->argv[1]);
UPDATE_MAPS(virt_mailbox_maps, VAR_VIRT_MAILBOX_MAPS,
var_virt_mailbox_maps, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX | DICT_FLAG_UTF8_REQUEST);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_VIRT_MAILBOX_DOMS) == 0) {
UPDATE_STRING(var_virt_mailbox_doms, args->argv[1]);
UPDATE_LIST(virt_mailbox_doms, VAR_VIRT_MAILBOX_DOMS,
var_virt_mailbox_doms);
smtpd_resolve_init(100);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_LOCAL_RCPT_MAPS) == 0) {
UPDATE_STRING(var_local_rcpt_maps, args->argv[1]);
UPDATE_MAPS(local_rcpt_maps, VAR_LOCAL_RCPT_MAPS,
var_local_rcpt_maps, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX | DICT_FLAG_UTF8_REQUEST);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_RELAY_RCPT_MAPS) == 0) {
UPDATE_STRING(var_relay_rcpt_maps, args->argv[1]);
UPDATE_MAPS(relay_rcpt_maps, VAR_RELAY_RCPT_MAPS,
var_relay_rcpt_maps, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX | DICT_FLAG_UTF8_REQUEST);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_CANONICAL_MAPS) == 0) {
UPDATE_STRING(var_canonical_maps, args->argv[1]);
UPDATE_MAPS(canonical_maps, VAR_CANONICAL_MAPS,
var_canonical_maps, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX | DICT_FLAG_UTF8_REQUEST);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_SEND_CANON_MAPS) == 0) {
UPDATE_STRING(var_send_canon_maps, args->argv[1]);
UPDATE_MAPS(send_canon_maps, VAR_SEND_CANON_MAPS,
var_send_canon_maps, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX | DICT_FLAG_UTF8_REQUEST);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_RCPT_CANON_MAPS) == 0) {
UPDATE_STRING(var_rcpt_canon_maps, args->argv[1]);
UPDATE_MAPS(rcpt_canon_maps, VAR_RCPT_CANON_MAPS,
var_rcpt_canon_maps, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX | DICT_FLAG_UTF8_REQUEST);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_RBL_REPLY_MAPS) == 0) {
UPDATE_STRING(var_rbl_reply_maps, args->argv[1]);
UPDATE_MAPS(rbl_reply_maps, VAR_RBL_REPLY_MAPS,
var_rbl_reply_maps, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX | DICT_FLAG_UTF8_REQUEST);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_MYNETWORKS) == 0) {
/* NOT: UPDATE_STRING */
namadr_list_free(mynetworks_curr);
mynetworks_curr =
namadr_list_init(VAR_MYNETWORKS, MATCH_FLAG_RETURN
| match_parent_style(VAR_MYNETWORKS),
args->argv[1]);
smtpd_resolve_init(100);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_RELAY_DOMAINS) == 0) {
/* NOT: UPDATE_STRING */
domain_list_free(relay_domains);
relay_domains =
domain_list_init(VAR_RELAY_DOMAINS,
match_parent_style(VAR_RELAY_DOMAINS),
args->argv[1]);
smtpd_resolve_init(100);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_PERM_MX_NETWORKS) == 0) {
UPDATE_STRING(var_perm_mx_networks, args->argv[1]);
domain_list_free(perm_mx_networks);
perm_mx_networks =
namadr_list_init(VAR_PERM_MX_NETWORKS, MATCH_FLAG_RETURN
| match_parent_style(VAR_PERM_MX_NETWORKS),
args->argv[1]);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_SMTPD_DNS_RE_FILTER) == 0) {
/* NOT: UPDATE_STRING */
dns_rr_filter_compile(VAR_SMTPD_DNS_RE_FILTER, args->argv[1]);
resp = 0;
break;
}
#ifdef USE_TLS
if (strcasecmp(args->argv[0], VAR_RELAY_CCERTS) == 0) {
UPDATE_STRING(var_smtpd_relay_ccerts, args->argv[1]);
UPDATE_MAPS(relay_ccerts, VAR_RELAY_CCERTS,
var_smtpd_relay_ccerts, DICT_FLAG_LOCK
| DICT_FLAG_FOLD_FIX);
resp = 0;
}
#endif
if (strcasecmp(args->argv[0], "restriction_class") == 0) {
rest_class(args->argv[1]);
resp = 0;
break;
}
if (strcasecmp(args->argv[0], VAR_LOC_RWR_CLIENTS) == 0) {
UPDATE_STRING(var_local_rwr_clients, args->argv[1]);
argv_free(local_rewrite_clients);
local_rewrite_clients = smtpd_check_parse(SMTPD_CHECK_PARSE_MAPS,
var_local_rwr_clients);
}
if (int_update(args->argv)
|| string_update(args->argv)
|| rest_update(args->argv)) {
resp = 0;
break;
}
/*
* Try restrictions.
*/
#define TRIM_ADDR(src, res) { \
if (*(res = src) == '<') { \
res += strlen(res) - 1; \
if (*res == '>') \
*res = 0; \
res = src + 1; \
} \
}
if (strcasecmp(args->argv[0], "helo") == 0) {
state.where = "HELO";
resp = smtpd_check_helo(&state, args->argv[1]);
UPDATE_STRING(state.helo_name, args->argv[1]);
} else if (strcasecmp(args->argv[0], "mail") == 0) {
state.where = "MAIL";
TRIM_ADDR(args->argv[1], addr);
UPDATE_STRING(state.sender, addr);
resp = smtpd_check_mail(&state, addr);
} else if (strcasecmp(args->argv[0], "rcpt") == 0) {
state.where = "RCPT";
TRIM_ADDR(args->argv[1], addr);
resp = smtpd_check_rcpt(&state, addr);
#ifdef USE_TLS
} else if (strcasecmp(args->argv[0], "fingerprint") == 0) {
if (state.tls_context == 0) {
state.tls_context =
(TLS_SESS_STATE *) mymalloc(sizeof(*state.tls_context));
memset((void *) state.tls_context, 0,
sizeof(*state.tls_context));
state.tls_context->peer_cert_fprint =
state.tls_context->peer_pkey_fprint = 0;
}
state.tls_context->peer_status |= TLS_CERT_FLAG_PRESENT;
UPDATE_STRING(state.tls_context->peer_cert_fprint,
args->argv[1]);
state.tls_context->peer_pkey_fprint =
state.tls_context->peer_cert_fprint;
resp = "OK";
break;
#endif
}
break;
/*
* Show commands.
*/
default:
if (strcasecmp(args->argv[0], "check_rewrite") == 0) {
smtpd_check_rewrite(&state);
resp = state.rewrite_context;
break;
}
resp = "Commands...\n\
client <name> <address> [<code>]\n\
helo <hostname>\n\
sender <address>\n\
recipient <address>\n\
check_rewrite\n\
msg_verbose <level>\n\
client_restrictions <restrictions>\n\
helo_restrictions <restrictions>\n\
sender_restrictions <restrictions>\n\
recipient_restrictions <restrictions>\n\
restriction_class name,<restrictions>\n\
flush_dnsxl_cache\n\
\n\
Note: no address rewriting \n";
break;
}
vstream_printf("%s\n", resp ? resp : "OK");
vstream_fflush(VSTREAM_OUT);
argv_free(args);
}
vstring_free(buf);
smtpd_state_reset(&state);
#define FREE_STRING(s) { if (s) myfree(s); }
FREE_STRING(state.helo_name);
FREE_STRING(state.sender);
#ifdef USE_TLS
if (state.tls_context) {
FREE_STRING(state.tls_context->peer_cert_fprint);
myfree((void *) state.tls_context);
}
#endif
exit(0);
}
#endif