| Current File : //root/postfix-3.2.0/src/trivial-rewrite/resolve.c |
/*++
/* NAME
/* resolve 3
/* SUMMARY
/* mail address resolver
/* SYNOPSIS
/* #include "trivial-rewrite.h"
/*
/* void resolve_init(void)
/*
/* int resolve_class(domain)
/* const char *domain;
/*
/* void resolve_proto(context, stream)
/* RES_CONTEXT *context;
/* VSTREAM *stream;
/* DESCRIPTION
/* This module implements the trivial address resolving engine.
/* It distinguishes between local and remote mail, and optionally
/* consults one or more transport tables that map a destination
/* to a transport, nexthop pair.
/*
/* resolve_init() initializes data structures that are private
/* to this module. It should be called once before using the
/* actual resolver routines.
/*
/* resolve_class() returns the address class for the specified
/* domain, or -1 in case of error.
/*
/* resolve_proto() implements the client-server protocol:
/* read one address in FQDN form, reply with a (transport,
/* nexthop, internalized recipient) triple.
/* STANDARDS
/* DIAGNOSTICS
/* Problems and transactions are logged to the syslog daemon.
/* BUGS
/* SEE ALSO
/* 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
/*--*/
/* System library. */
#include <sys_defs.h>
#include <stdlib.h>
#include <string.h>
#ifdef STRCASECMP_IN_STRINGS_H
#include <strings.h>
#endif
/* Utility library. */
#include <msg.h>
#include <vstring.h>
#include <vstream.h>
#include <vstring_vstream.h>
#include <split_at.h>
#include <valid_utf8_hostname.h>
#include <stringops.h>
#include <mymalloc.h>
/* Global library. */
#include <mail_params.h>
#include <mail_proto.h>
#include <resolve_local.h>
#include <mail_conf.h>
#include <quote_822_local.h>
#include <tok822.h>
#include <domain_list.h>
#include <string_list.h>
#include <match_parent_style.h>
#include <maps.h>
#include <mail_addr_find.h>
#include <valid_mailhost_addr.h>
/* Application-specific. */
#include "trivial-rewrite.h"
#include "transport.h"
/*
* The job of the address resolver is to map one recipient address to a
* triple of (channel, nexthop, recipient). The channel is the name of the
* delivery service specified in master.cf, the nexthop is (usually) a
* description of the next host to deliver to, and recipient is the final
* recipient address. The latter may differ from the input address as the
* result of stripping multiple layers of sender-specified routing.
*
* Addresses are resolved by their domain name. Known domain names are
* categorized into classes: local, virtual alias, virtual mailbox, relay,
* and everything else. Finding the address domain class is a matter of
* table lookups.
*
* Different address domain classes generally use different delivery channels,
* and may use class dependent ways to arrive at the corresponding nexthop
* information. With classes that do final delivery, the nexthop is
* typically the local machine hostname.
*
* The transport lookup table provides a means to override the domain class
* channel and/or nexhop information for specific recipients or for entire
* domain hierarchies.
*
* This works well in the general case. The only bug in this approach is that
* the structure of the nexthop information is transport dependent.
* Typically, the nexthop specifies a hostname, hostname + TCP Port, or the
* pathname of a UNIX-domain socket. However, with the error transport the
* nexthop field contains free text with the reason for non-delivery.
*
* Therefore, a transport map entry that overrides the channel but not the
* nexthop information (or vice versa) may produce surprising results. In
* particular, the free text nexthop information for the error transport is
* likely to confuse regular delivery agents; and conversely, a hostname or
* socket pathname is not an adequate text as reason for non-delivery.
*
* In the code below, rcpt_domain specifies the domain name that we will use
* when the transport table specifies a non-default channel but no nexthop
* information (we use a generic text when that non-default channel is the
* error transport).
*/
#define STR vstring_str
#define LEN VSTRING_LEN
/*
* Some of the lists that define the address domain classes.
*/
static DOMAIN_LIST *relay_domains;
static STRING_LIST *virt_alias_doms;
static STRING_LIST *virt_mailbox_doms;
static MAPS *relocated_maps;
/* resolve_class - determine domain address class */
int resolve_class(const char *domain)
{
int ret;
/*
* Same order as in resolve_addr().
*/
if ((ret = resolve_local(domain)) != 0)
return (ret > 0 ? RESOLVE_CLASS_LOCAL : -1);
if (virt_alias_doms) {
if (string_list_match(virt_alias_doms, domain))
return (RESOLVE_CLASS_ALIAS);
if (virt_alias_doms->error)
return (-1);
}
if (virt_mailbox_doms) {
if (string_list_match(virt_mailbox_doms, domain))
return (RESOLVE_CLASS_VIRTUAL);
if (virt_mailbox_doms->error)
return (-1);
}
if (relay_domains) {
if (string_list_match(relay_domains, domain))
return (RESOLVE_CLASS_RELAY);
if (relay_domains->error)
return (-1);
}
return (RESOLVE_CLASS_DEFAULT);
}
/* resolve_addr - resolve address according to rule set */
static void resolve_addr(RES_CONTEXT *rp, char *sender, char *addr,
VSTRING *channel, VSTRING *nexthop,
VSTRING *nextrcpt, int *flags)
{
const char *myname = "resolve_addr";
VSTRING *addr_buf = vstring_alloc(100);
TOK822 *tree = 0;
TOK822 *saved_domain = 0;
TOK822 *domain = 0;
char *destination;
const char *blame = 0;
const char *rcpt_domain;
ssize_t addr_len;
ssize_t loop_count;
ssize_t loop_max;
char *local;
char *oper;
char *junk;
const char *relay;
const char *xport;
const char *sender_key;
int rc;
*flags = 0;
vstring_strcpy(channel, "CHANNEL NOT UPDATED");
vstring_strcpy(nexthop, "NEXTHOP NOT UPDATED");
vstring_strcpy(nextrcpt, "NEXTRCPT NOT UPDATED");
/*
* The address is in internalized (unquoted) form.
*
* In an ideal world we would parse the externalized address form as given
* to us by the sender.
*
* However, in the real world we have to look for routing characters like
* %@! in the address local-part, even when that information is quoted
* due to the presence of special characters or whitespace. Although
* technically incorrect, this is needed to stop user@domain@domain relay
* attempts when forwarding mail to a Sendmail MX host.
*
* This suggests that we parse the address in internalized (unquoted) form.
* Unfortunately, if we do that, the unparser generates incorrect white
* space between adjacent non-operator tokens. Example: ``first last''
* needs white space, but ``stuff[stuff]'' does not. This is is not a
* problem when unparsing the result from parsing externalized forms,
* because the parser/unparser were designed for valid externalized forms
* where ``stuff[stuff]'' does not happen.
*
* As a workaround we start with the quoted form and then dequote the
* local-part only where needed. This will do the right thing in most
* (but not all) cases.
*/
addr_len = strlen(addr);
quote_822_local(addr_buf, addr);
tree = tok822_scan_addr(vstring_str(addr_buf));
/*
* The optimizer will eliminate tests that always fail, and will replace
* multiple expansions of this macro by a GOTO to a single instance.
*/
#define FREE_MEMORY_AND_RETURN { \
if (saved_domain) \
tok822_free_tree(saved_domain); \
if(tree) \
tok822_free_tree(tree); \
if (addr_buf) \
vstring_free(addr_buf); \
return; \
}
/*
* Preliminary resolver: strip off all instances of the local domain.
* Terminate when no destination domain is left over, or when the
* destination domain is remote.
*
* XXX To whom it may concern. If you change the resolver loop below, or
* quote_822_local.c, or tok822_parse.c, be sure to re-run the tests
* under "make resolve_clnt_test" in the global directory.
*/
#define RESOLVE_LOCAL(domain) \
resolve_local(STR(tok822_internalize(addr_buf, domain, TOK822_STR_DEFL)))
for (loop_count = 0, loop_max = addr_len + 100; /* void */ ; loop_count++) {
/*
* XXX Should never happen, but if this happens with some
* pathological address, then that is not sufficient reason to
* disrupt the operation of an MTA.
*/
if (loop_count > loop_max) {
msg_warn("resolve_addr: <%s>: giving up after %ld iterations",
addr, (long) loop_count);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
break;
}
/*
* Strip trailing dot at end of domain, but not dot-dot or at-dot.
* This merely makes diagnostics more accurate by leaving bogus
* addresses alone.
*/
if (tree->tail
&& tree->tail->type == '.'
&& tok822_rfind_type(tree->tail, '@') != 0
&& tree->tail->prev->type != '.'
&& tree->tail->prev->type != '@')
tok822_free_tree(tok822_sub_keep_before(tree, tree->tail));
/*
* Strip trailing @.
*/
if (var_resolve_nulldom
&& tree->tail
&& tree->tail->type == '@')
tok822_free_tree(tok822_sub_keep_before(tree, tree->tail));
/*
* Strip (and save) @domain if local.
*
* Grr. resolve_local() table lookups may fail. It may be OK for local
* file lookup code to abort upon failure, but with network-based
* tables it is preferable to return an error indication to the
* requestor.
*/
if ((domain = tok822_rfind_type(tree->tail, '@')) != 0) {
if (domain->next && (rc = RESOLVE_LOCAL(domain->next)) <= 0) {
if (rc < 0) {
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
}
break;
}
tok822_sub_keep_before(tree, domain);
if (saved_domain)
tok822_free_tree(saved_domain);
saved_domain = domain;
domain = 0; /* safety for future change */
}
/*
* After stripping the local domain, if any, replace foo%bar by
* foo@bar, site!user by user@site, rewrite to canonical form, and
* retry.
*/
if (tok822_rfind_type(tree->tail, '@')
|| (var_swap_bangpath && tok822_rfind_type(tree->tail, '!'))
|| (var_percent_hack && tok822_rfind_type(tree->tail, '%'))) {
rewrite_tree(&local_context, tree);
continue;
}
/*
* If the local-part is a quoted string, crack it open when we're
* permitted to do so and look for routing operators. This is
* technically incorrect, but is needed to stop relaying problems.
*
* XXX Do another feeble attempt to keep local-part info quoted.
*/
if (var_resolve_dequoted
&& tree->head && tree->head == tree->tail
&& tree->head->type == TOK822_QSTRING
&& ((oper = strrchr(local = STR(tree->head->vstr), '@')) != 0
|| (var_percent_hack && (oper = strrchr(local, '%')) != 0)
|| (var_swap_bangpath && (oper = strrchr(local, '!')) != 0))) {
if (*oper == '%')
*oper = '@';
tok822_internalize(addr_buf, tree->head, TOK822_STR_DEFL);
if (*oper == '@') {
junk = mystrdup(STR(addr_buf));
quote_822_local(addr_buf, junk);
myfree(junk);
}
tok822_free(tree->head);
tree->head = tok822_scan(STR(addr_buf), &tree->tail);
rewrite_tree(&local_context, tree);
continue;
}
/*
* An empty local-part or an empty quoted string local-part becomes
* the local MAILER-DAEMON, for consistency with our own From:
* message headers.
*/
if (tree->head && tree->head == tree->tail
&& tree->head->type == TOK822_QSTRING
&& VSTRING_LEN(tree->head->vstr) == 0) {
tok822_free(tree->head);
tree->head = 0;
}
/* XXX Re-resolve the surrogate, in case already in user@domain form. */
if (tree->head == 0) {
tree->head = tok822_scan(var_empty_addr, &tree->tail);
continue;
}
/* XXX Re-resolve with @$myhostname for backwards compatibility. */
if (domain == 0 && saved_domain == 0) {
tok822_sub_append(tree, tok822_alloc('@', (char *) 0));
tok822_sub_append(tree, tok822_scan(var_myhostname, (TOK822 **) 0));
continue;
}
/*
* We're done. There are no domains left to strip off the address,
* and all null local-part information is sanitized.
*/
domain = 0;
break;
}
vstring_free(addr_buf);
addr_buf = 0;
/*
* Make sure the resolved envelope recipient has the user@domain form. If
* no domain was specified in the address, assume the local machine. See
* above for what happens with an empty address.
*/
if (domain == 0) {
if (saved_domain) {
tok822_sub_append(tree, saved_domain);
saved_domain = 0;
} else {
tok822_sub_append(tree, tok822_alloc('@', (char *) 0));
tok822_sub_append(tree, tok822_scan(var_myhostname, (TOK822 **) 0));
}
}
/*
* Transform the recipient address back to internal form.
*
* XXX This may produce incorrect results if we cracked open a quoted
* local-part with routing operators; see discussion above at the top of
* the big loop.
*
* XXX We explicitly disallow domain names in bare network address form. A
* network address destination should be formatted according to RFC 2821:
* it should be enclosed in [], and an IPv6 address should have an IPv6:
* prefix.
*/
tok822_internalize(nextrcpt, tree, TOK822_STR_DEFL);
rcpt_domain = strrchr(STR(nextrcpt), '@') + 1;
if (rcpt_domain == (char *) 1)
msg_panic("no @ in address: \"%s\"", STR(nextrcpt));
if (*rcpt_domain == '[') {
if (!valid_mailhost_literal(rcpt_domain, DONT_GRIPE))
*flags |= RESOLVE_FLAG_ERROR;
} else if (var_smtputf8_enable
&& valid_utf8_string(STR(nextrcpt), LEN(nextrcpt)) == 0) {
*flags |= RESOLVE_FLAG_ERROR;
} else if (!valid_utf8_hostname(var_smtputf8_enable, rcpt_domain,
DONT_GRIPE)) {
if (var_resolve_num_dom && valid_hostaddr(rcpt_domain, DONT_GRIPE)) {
vstring_insert(nextrcpt, rcpt_domain - STR(nextrcpt), "[", 1);
vstring_strcat(nextrcpt, "]");
rcpt_domain = strrchr(STR(nextrcpt), '@') + 1;
if ((rc = resolve_local(rcpt_domain)) > 0) /* XXX */
domain = 0;
else if (rc < 0) {
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
}
} else {
*flags |= RESOLVE_FLAG_ERROR;
}
}
tok822_free_tree(tree);
tree = 0;
/*
* XXX Short-cut invalid address forms.
*/
if (*flags & RESOLVE_FLAG_ERROR) {
*flags |= RESOLVE_CLASS_DEFAULT;
FREE_MEMORY_AND_RETURN;
}
/*
* Recognize routing operators in the local-part, even when we do not
* recognize ! or % as valid routing operators locally. This is needed to
* prevent backup MX hosts from relaying third-party destinations through
* primary MX hosts, otherwise the backup host could end up on black
* lists. Ignore local swap_bangpath and percent_hack settings because we
* can't know how the next MX host is set up.
*/
if (strcmp(STR(nextrcpt) + strcspn(STR(nextrcpt), "@!%") + 1, rcpt_domain))
*flags |= RESOLVE_FLAG_ROUTED;
/*
* With local, virtual, relay, or other non-local destinations, give the
* highest precedence to transport associated nexthop information.
*
* Otherwise, with relay or other non-local destinations, the relayhost
* setting overrides the recipient domain name, and the sender-dependent
* relayhost overrides both.
*
* XXX Nag if the recipient domain is listed in multiple domain lists. The
* result is implementation defined, and may break when internals change.
*
* For now, we distinguish only a fixed number of address classes.
* Eventually this may become extensible, so that new classes can be
* configured with their own domain list, delivery transport, and
* recipient table.
*/
#define STREQ(x,y) (strcmp((x), (y)) == 0)
if (domain != 0) {
/*
* Virtual alias domain.
*/
if (virt_alias_doms
&& string_list_match(virt_alias_doms, rcpt_domain)) {
if (var_helpful_warnings) {
if (virt_mailbox_doms
&& string_list_match(virt_mailbox_doms, rcpt_domain))
msg_warn("do not list domain %s in BOTH %s and %s",
rcpt_domain, VAR_VIRT_ALIAS_DOMS,
VAR_VIRT_MAILBOX_DOMS);
if (relay_domains
&& domain_list_match(relay_domains, rcpt_domain))
msg_warn("do not list domain %s in BOTH %s and %s",
rcpt_domain, VAR_VIRT_ALIAS_DOMS,
VAR_RELAY_DOMAINS);
#if 0
if (strcasecmp_utf8(rcpt_domain, var_myorigin) == 0)
msg_warn("do not list $%s (%s) in %s",
VAR_MYORIGIN, var_myorigin, VAR_VIRT_ALIAS_DOMS);
#endif
}
vstring_strcpy(channel, MAIL_SERVICE_ERROR);
vstring_sprintf(nexthop, "5.1.1 User unknown%s",
var_show_unk_rcpt_table ?
" in virtual alias table" : "");
*flags |= RESOLVE_CLASS_ALIAS;
} else if (virt_alias_doms && virt_alias_doms->error != 0) {
msg_warn("%s lookup failure", VAR_VIRT_ALIAS_DOMS);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
}
/*
* Virtual mailbox domain.
*/
else if (virt_mailbox_doms
&& string_list_match(virt_mailbox_doms, rcpt_domain)) {
if (var_helpful_warnings) {
if (relay_domains
&& domain_list_match(relay_domains, rcpt_domain))
msg_warn("do not list domain %s in BOTH %s and %s",
rcpt_domain, VAR_VIRT_MAILBOX_DOMS,
VAR_RELAY_DOMAINS);
}
vstring_strcpy(channel, RES_PARAM_VALUE(rp->virt_transport));
vstring_strcpy(nexthop, rcpt_domain);
blame = rp->virt_transport_name;
*flags |= RESOLVE_CLASS_VIRTUAL;
} else if (virt_mailbox_doms && virt_mailbox_doms->error != 0) {
msg_warn("%s lookup failure", VAR_VIRT_MAILBOX_DOMS);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
} else {
/*
* Off-host relay destination.
*/
if (relay_domains
&& domain_list_match(relay_domains, rcpt_domain)) {
vstring_strcpy(channel, RES_PARAM_VALUE(rp->relay_transport));
blame = rp->relay_transport_name;
*flags |= RESOLVE_CLASS_RELAY;
} else if (relay_domains && relay_domains->error != 0) {
msg_warn("%s lookup failure", VAR_RELAY_DOMAINS);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
}
/*
* Other off-host destination.
*/
else {
if (rp->snd_def_xp_info
&& (xport = mail_addr_find(rp->snd_def_xp_info,
sender_key = (*sender ? sender :
var_null_def_xport_maps_key),
(char **) 0)) != 0) {
if (*xport == 0) {
msg_warn("%s: ignoring null lookup result for %s",
rp->snd_def_xp_maps_name, sender_key);
xport = "DUNNO";
}
vstring_strcpy(channel, strcasecmp(xport, "DUNNO") == 0 ?
RES_PARAM_VALUE(rp->def_transport) : xport);
blame = rp->snd_def_xp_maps_name;
} else if (rp->snd_def_xp_info
&& rp->snd_def_xp_info->error != 0) {
msg_warn("%s lookup failure", rp->snd_def_xp_maps_name);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
} else {
vstring_strcpy(channel, RES_PARAM_VALUE(rp->def_transport));
blame = rp->def_transport_name;
}
*flags |= RESOLVE_CLASS_DEFAULT;
}
/*
* With off-host delivery, sender-dependent or global relayhost
* override the recipient domain.
*/
if (rp->snd_relay_info
&& (relay = mail_addr_find(rp->snd_relay_info,
sender_key = (*sender ? sender :
var_null_relay_maps_key),
(char **) 0)) != 0) {
if (*relay == 0) {
msg_warn("%s: ignoring null lookup result for %s",
rp->snd_relay_maps_name, sender_key);
relay = 0;
} else if (strcasecmp_utf8(relay, "DUNNO") == 0)
relay = 0;
} else if (rp->snd_relay_info
&& rp->snd_relay_info->error != 0) {
msg_warn("%s lookup failure", rp->snd_relay_maps_name);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
} else {
relay = 0;
}
/* Enforce all the relayhost precedences in one place. */
if (relay != 0) {
vstring_strcpy(nexthop, relay);
} else if (*RES_PARAM_VALUE(rp->relayhost))
vstring_strcpy(nexthop, RES_PARAM_VALUE(rp->relayhost));
else
vstring_strcpy(nexthop, rcpt_domain);
}
}
/*
* Local delivery.
*
* XXX Nag if the domain is listed in multiple domain lists. The effect is
* implementation defined, and may break when internals change.
*/
else {
if (var_helpful_warnings) {
if (virt_alias_doms
&& string_list_match(virt_alias_doms, rcpt_domain))
msg_warn("do not list domain %s in BOTH %s and %s",
rcpt_domain, VAR_MYDEST, VAR_VIRT_ALIAS_DOMS);
if (virt_mailbox_doms
&& string_list_match(virt_mailbox_doms, rcpt_domain))
msg_warn("do not list domain %s in BOTH %s and %s",
rcpt_domain, VAR_MYDEST, VAR_VIRT_MAILBOX_DOMS);
}
vstring_strcpy(channel, RES_PARAM_VALUE(rp->local_transport));
vstring_strcpy(nexthop, rcpt_domain);
blame = rp->local_transport_name;
*flags |= RESOLVE_CLASS_LOCAL;
}
/*
* An explicit main.cf transport:nexthop setting overrides the nexthop.
*
* XXX We depend on this mechanism to enforce per-recipient concurrencies
* for local recipients. With "local_transport = local:$myhostname" we
* force mail for any domain in $mydestination/${proxy,inet}_interfaces
* to share the same queue.
*/
if ((destination = split_at(STR(channel), ':')) != 0 && *destination)
vstring_strcpy(nexthop, destination);
/*
* Sanity checks.
*/
if (*STR(channel) == 0) {
if (blame == 0)
msg_panic("%s: null blame", myname);
msg_warn("file %s/%s: parameter %s: null transport is not allowed",
var_config_dir, MAIN_CONF_FILE, blame);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
}
if (*STR(nexthop) == 0)
msg_panic("%s: null nexthop", myname);
/*
* The transport map can selectively override any transport and/or
* nexthop host info that is set up above. Unfortunately, the syntax for
* nexthop information is transport specific. We therefore need sane and
* intuitive semantics for transport map entries that specify a channel
* but no nexthop.
*
* With non-error transports, the initial nexthop information is the
* recipient domain. However, specific main.cf transport definitions may
* specify a transport-specific destination, such as a host + TCP socket,
* or the pathname of a UNIX-domain socket. With less precedence than
* main.cf transport definitions, a main.cf relayhost definition may also
* override nexthop information for off-host deliveries.
*
* With the error transport, the nexthop information is free text that
* specifies the reason for non-delivery.
*
* Because nexthop syntax is transport specific we reset the nexthop
* information to the recipient domain when the transport table specifies
* a transport without also specifying the nexthop information.
*
* Subtle note: reset nexthop even when the transport table does not change
* the transport. Otherwise it is hard to get rid of main.cf specified
* nexthop information.
*
* XXX Don't override the virtual alias class (error:User unknown) result.
*/
if (rp->transport_info && !(*flags & RESOLVE_CLASS_ALIAS)) {
if (transport_lookup(rp->transport_info, STR(nextrcpt),
rcpt_domain, channel, nexthop) == 0
&& rp->transport_info->transport_path->error != 0) {
msg_warn("%s lookup failure", rp->transport_maps_name);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
}
}
/*
* Bounce recipients that have moved, regardless of domain address class.
* We do this last, in anticipation of transport maps that can override
* the recipient address.
*
* The downside of not doing this in delivery agents is that this table has
* no effect on local alias expansion results. Such mail will have to
* make almost an entire iteration through the mail system.
*/
#define IGNORE_ADDR_EXTENSION ((char **) 0)
if (relocated_maps != 0) {
const char *newloc;
if ((newloc = mail_addr_find(relocated_maps, STR(nextrcpt),
IGNORE_ADDR_EXTENSION)) != 0) {
vstring_strcpy(channel, MAIL_SERVICE_ERROR);
/* 5.1.6 is the closest match, but not perfect. */
vstring_sprintf(nexthop, "5.1.6 User has moved to %s", newloc);
} else if (relocated_maps->error != 0) {
msg_warn("%s lookup failure", VAR_RELOCATED_MAPS);
*flags |= RESOLVE_FLAG_FAIL;
FREE_MEMORY_AND_RETURN;
}
}
/*
* Bounce recipient addresses that start with `-'. External commands may
* misinterpret such addresses as command-line options.
*
* In theory I could say people should always carefully set up their
* master.cf pipe mailer entries with `--' before the first non-option
* argument, but mistakes will happen regardless.
*
* Therefore the protection is put in place here, where it cannot be
* bypassed.
*/
if (var_allow_min_user == 0 && STR(nextrcpt)[0] == '-') {
*flags |= RESOLVE_FLAG_ERROR;
FREE_MEMORY_AND_RETURN;
}
/*
* Clean up.
*/
FREE_MEMORY_AND_RETURN;
}
/* Static, so they can be used by the network protocol interface only. */
static VSTRING *channel;
static VSTRING *nexthop;
static VSTRING *nextrcpt;
static VSTRING *query;
static VSTRING *sender;
/* resolve_proto - read request and send reply */
int resolve_proto(RES_CONTEXT *context, VSTREAM *stream)
{
int flags;
if (attr_scan(stream, ATTR_FLAG_STRICT,
RECV_ATTR_STR(MAIL_ATTR_SENDER, sender),
RECV_ATTR_STR(MAIL_ATTR_ADDR, query),
ATTR_TYPE_END) != 2)
return (-1);
resolve_addr(context, STR(sender), STR(query),
channel, nexthop, nextrcpt, &flags);
if (msg_verbose)
msg_info("`%s' -> `%s' -> (`%s' `%s' `%s' `%d')",
STR(sender), STR(query), STR(channel),
STR(nexthop), STR(nextrcpt), flags);
attr_print(stream, ATTR_FLAG_NONE,
SEND_ATTR_INT(MAIL_ATTR_FLAGS, server_flags),
SEND_ATTR_STR(MAIL_ATTR_TRANSPORT, STR(channel)),
SEND_ATTR_STR(MAIL_ATTR_NEXTHOP, STR(nexthop)),
SEND_ATTR_STR(MAIL_ATTR_RECIP, STR(nextrcpt)),
SEND_ATTR_INT(MAIL_ATTR_FLAGS, flags),
ATTR_TYPE_END);
if (vstream_fflush(stream) != 0) {
msg_warn("write resolver reply: %m");
return (-1);
}
return (0);
}
/* resolve_init - module initializations */
void resolve_init(void)
{
sender = vstring_alloc(100);
query = vstring_alloc(100);
channel = vstring_alloc(100);
nexthop = vstring_alloc(100);
nextrcpt = vstring_alloc(100);
if (*var_virt_alias_doms)
virt_alias_doms =
string_list_init(VAR_VIRT_ALIAS_DOMS, MATCH_FLAG_RETURN,
var_virt_alias_doms);
if (*var_virt_mailbox_doms)
virt_mailbox_doms =
string_list_init(VAR_VIRT_MAILBOX_DOMS, MATCH_FLAG_RETURN,
var_virt_mailbox_doms);
if (*var_relay_domains)
relay_domains =
domain_list_init(VAR_RELAY_DOMAINS, MATCH_FLAG_RETURN
| match_parent_style(VAR_RELAY_DOMAINS),
var_relay_domains);
if (*var_relocated_maps)
relocated_maps =
maps_create(VAR_RELOCATED_MAPS, var_relocated_maps,
DICT_FLAG_LOCK | DICT_FLAG_FOLD_FIX
| DICT_FLAG_UTF8_REQUEST);
}