| Current File : //root/postfix-3.2.0/src/cleanup/cleanup_api.c |
/*++
/* NAME
/* cleanup_api 3
/* SUMMARY
/* cleanup callable interface, message processing
/* SYNOPSIS
/* #include "cleanup.h"
/*
/* CLEANUP_STATE *cleanup_open(src)
/* VSTREAM *src;
/*
/* void cleanup_control(state, flags)
/* CLEANUP_STATE *state;
/* int flags;
/*
/* void CLEANUP_RECORD(state, type, buf, len)
/* CLEANUP_STATE *state;
/* int type;
/* char *buf;
/* int len;
/*
/* int cleanup_flush(state)
/* CLEANUP_STATE *state;
/*
/* int cleanup_free(state)
/* CLEANUP_STATE *state;
/* DESCRIPTION
/* This module implements a callable interface to the cleanup service
/* for processing one message and for writing it to queue file.
/* For a description of the cleanup service, see cleanup(8).
/*
/* cleanup_open() creates a new queue file and performs other
/* per-message initialization. The result is a handle that should be
/* given to the cleanup_control(), cleanup_record(), cleanup_flush()
/* and cleanup_free() routines. The name of the queue file is in the
/* queue_id result structure member.
/*
/* cleanup_control() processes per-message flags specified by the caller.
/* These flags control the handling of data errors, and must be set
/* before processing the first message record.
/* .IP CLEANUP_FLAG_BOUNCE
/* The cleanup server is responsible for returning undeliverable
/* mail (too many hops, message too large) to the sender.
/* .IP CLEANUP_FLAG_BCC_OK
/* It is OK to add automatic BCC recipient addresses.
/* .IP CLEANUP_FLAG_FILTER
/* Enable header/body filtering. This should be enabled only with mail
/* that enters Postfix, not with locally forwarded mail or with bounce
/* messages.
/* .IP CLEANUP_FLAG_MILTER
/* Enable Milter applications. This should be enabled only with mail
/* that enters Postfix, not with locally forwarded mail or with bounce
/* messages.
/* .IP CLEANUP_FLAG_MAP_OK
/* Enable canonical and virtual mapping, and address masquerading.
/* .PP
/* For convenience the CLEANUP_FLAG_MASK_EXTERNAL macro specifies
/* the options that are normally needed for mail that enters
/* Postfix from outside, and CLEANUP_FLAG_MASK_INTERNAL specifies
/* the options that are normally needed for internally generated or
/* forwarded mail.
/*
/* CLEANUP_RECORD() is a macro that processes one message record,
/* that copies the result to the queue file, and that maintains a
/* little state machine. The last record in a valid message has type
/* REC_TYPE_END. In order to find out if a message is corrupted,
/* the caller is encouraged to test the CLEANUP_OUT_OK(state) macro.
/* The result is false when further message processing is futile.
/* In that case, it is safe to call cleanup_flush() immediately.
/*
/* cleanup_flush() closes a queue file. In case of any errors,
/* the file is removed. The result value is non-zero in case of
/* problems. In some cases a human-readable text can be found in
/* the state->reason member. In all other cases, use cleanup_strerror()
/* to translate the result into human-readable text.
/*
/* cleanup_free() destroys its argument.
/* .IP CLEANUP_FLAG_SMTPUTF8
/* Request SMTPUTF8 support when delivering mail.
/* .IP CLEANUP_FLAG_AUTOUTF8
/* Autodetection: request SMTPUTF8 support if the message
/* contains an UTF8 message header, sender, or recipient.
/* DIAGNOSTICS
/* Problems and transactions are logged to \fBsyslogd\fR(8).
/* SEE ALSO
/* cleanup(8) cleanup service description.
/* cleanup_init(8) cleanup callable interface, initialization
/* 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
/*--*/
/* System library. */
#include <sys_defs.h>
#include <errno.h>
/* Utility library. */
#include <msg.h>
#include <vstring.h>
#include <mymalloc.h>
/* Global library. */
#include <cleanup_user.h>
#include <mail_queue.h>
#include <mail_proto.h>
#include <bounce.h>
#include <mail_params.h>
#include <mail_stream.h>
#include <mail_flow.h>
#include <rec_type.h>
#include <smtputf8.h>
/* Milter library. */
#include <milter.h>
/* Application-specific. */
#include "cleanup.h"
/* cleanup_open - open queue file and initialize */
CLEANUP_STATE *cleanup_open(VSTREAM *src)
{
CLEANUP_STATE *state;
static const char *log_queues[] = {
MAIL_QUEUE_DEFER,
MAIL_QUEUE_BOUNCE,
MAIL_QUEUE_TRACE,
0,
};
const char **cpp;
/*
* Initialize private state.
*/
state = cleanup_state_alloc(src);
/*
* Open the queue file. Save the queue file name in a global variable, so
* that the runtime error handler can clean up in case of problems.
*
* XXX For now, a lot of detail is frozen that could be more useful if it
* were made configurable.
*/
state->queue_name = mystrdup(MAIL_QUEUE_INCOMING);
state->handle = mail_stream_file(state->queue_name,
MAIL_CLASS_PUBLIC, var_queue_service, 0);
state->dst = state->handle->stream;
cleanup_path = mystrdup(VSTREAM_PATH(state->dst));
state->queue_id = mystrdup(state->handle->id);
if (msg_verbose)
msg_info("cleanup_open: open %s", cleanup_path);
/*
* If there is a time to get rid of spurious log files, this is it. The
* down side is that this costs performance for every message, while the
* probability of spurious log files is quite low.
*
* XXX The defer logfile is deleted when the message is moved into the
* active queue. We must also remove it now, otherwise mailq produces
* nonsense.
*/
for (cpp = log_queues; *cpp; cpp++) {
if (mail_queue_remove(*cpp, state->queue_id) == 0)
msg_warn("%s: removed spurious %s log", *cpp, state->queue_id);
else if (errno != ENOENT)
msg_fatal("%s: remove %s log: %m", *cpp, state->queue_id);
}
return (state);
}
/* cleanup_control - process client options */
void cleanup_control(CLEANUP_STATE *state, int flags)
{
/*
* If the client requests us to do the bouncing in case of problems,
* throw away the input only in case of real show-stopper errors, such as
* unrecognizable data (which should never happen) or insufficient space
* for the queue file (which will happen occasionally). Otherwise,
* discard input after any lethal error. See the CLEANUP_OUT_OK() macro
* definition.
*/
if (msg_verbose)
msg_info("cleanup flags = %s", cleanup_strflags(flags));
if ((state->flags = flags) & CLEANUP_FLAG_BOUNCE) {
state->err_mask = CLEANUP_STAT_MASK_INCOMPLETE;
} else {
state->err_mask = ~0;
}
if (state->flags & CLEANUP_FLAG_SMTPUTF8)
state->smtputf8 = SMTPUTF8_FLAG_REQUESTED;
}
/* cleanup_flush - finish queue file */
int cleanup_flush(CLEANUP_STATE *state)
{
int status;
char *junk;
VSTRING *trace_junk;
/*
* Raise these errors only if we examined all queue file records.
*/
if (CLEANUP_OUT_OK(state)) {
if (state->recip == 0)
state->errs |= CLEANUP_STAT_RCPT;
if ((state->flags & CLEANUP_FLAG_END_SEEN) == 0)
state->errs |= CLEANUP_STAT_BAD;
}
/*
* Status sanitization. Always report success when the discard flag was
* raised by some user-specified access rule.
*/
if (state->flags & CLEANUP_FLAG_DISCARD)
state->errs = 0;
/*
* Apply external mail filter.
*
* XXX Include test for a built-in action to tempfail this message.
*/
if (CLEANUP_MILTER_OK(state)) {
if (state->milters)
cleanup_milter_inspect(state, state->milters);
else if (cleanup_milters) {
cleanup_milter_emul_data(state, cleanup_milters);
if (CLEANUP_MILTER_OK(state))
cleanup_milter_inspect(state, cleanup_milters);
}
}
/*
* Update the preliminary message size and count fields with the actual
* values.
*/
if (CLEANUP_OUT_OK(state))
cleanup_final(state);
/*
* If there was an error that requires us to generate a bounce message
* (mail submitted with the Postfix sendmail command, mail forwarded by
* the local(8) delivery agent, or mail re-queued with "postsuper -r"),
* send a bounce notification, reset the error flags in case of success,
* and request deletion of the the incoming queue file and of the
* optional DSN SUCCESS records from virtual alias expansion.
*
* XXX It would make no sense to knowingly report success after we already
* have bounced all recipients, especially because the information in the
* DSN SUCCESS notice is completely redundant compared to the information
* in the bounce notice (however, both may be incomplete when the queue
* file size would exceed the safety limit).
*
* An alternative is to keep the DSN SUCCESS records and to delegate bounce
* notification to the queue manager, just like we already delegate
* success notification. This requires that we leave the undeliverable
* message in the incoming queue; versions up to 20050726 did exactly
* that. Unfortunately, this broke with over-size queue files, because
* the queue manager cannot handle incomplete queue files (and it should
* not try to do so).
*/
#define CAN_BOUNCE() \
((state->errs & CLEANUP_STAT_MASK_CANT_BOUNCE) == 0 \
&& state->sender != 0 \
&& (state->flags & CLEANUP_FLAG_BOUNCE) != 0)
if (state->errs != 0 && CAN_BOUNCE())
cleanup_bounce(state);
/*
* Optionally, place the message on hold, but only if the message was
* received successfully and only if it's not being discarded for other
* reasons. This involves renaming the queue file before "finishing" it
* (or else the queue manager would grab it too early) and updating our
* own idea of the queue file name for error recovery and for error
* reporting purposes.
*
* XXX Include test for a built-in action to tempfail this message.
*/
if (state->errs == 0 && (state->flags & CLEANUP_FLAG_DISCARD) == 0) {
if ((state->flags & CLEANUP_FLAG_HOLD) != 0
#ifdef DELAY_ACTION
|| state->defer_delay > 0
#endif
) {
myfree(state->queue_name);
#ifdef DELAY_ACTION
state->queue_name = mystrdup((state->flags & CLEANUP_FLAG_HOLD) ?
MAIL_QUEUE_HOLD : MAIL_QUEUE_DEFERRED);
#else
state->queue_name = mystrdup(MAIL_QUEUE_HOLD);
#endif
mail_stream_ctl(state->handle,
CA_MAIL_STREAM_CTL_QUEUE(state->queue_name),
CA_MAIL_STREAM_CTL_CLASS((char *) 0),
CA_MAIL_STREAM_CTL_SERVICE((char *) 0),
#ifdef DELAY_ACTION
CA_MAIL_STREAM_CTL_DELAY(state->defer_delay),
#endif
CA_MAIL_STREAM_CTL_END);
junk = cleanup_path;
cleanup_path = mystrdup(VSTREAM_PATH(state->handle->stream));
myfree(junk);
/*
* XXX: When delivering to a non-incoming queue, do not consume
* in_flow tokens. Unfortunately we can't move the code that
* consumes tokens until after the mail is received, because that
* would increase the risk of duplicate deliveries (RFC 1047).
*/
(void) mail_flow_put(1);
}
state->errs = mail_stream_finish(state->handle, (VSTRING *) 0);
} else {
/*
* XXX: When discarding mail, should we consume in_flow tokens? See
* also the comments above for mail that is placed on hold.
*/
#if 0
(void) mail_flow_put(1);
#endif
mail_stream_cleanup(state->handle);
}
state->handle = 0;
state->dst = 0;
/*
* If there was an error, or if the message must be discarded for other
* reasons, remove the queue file and the optional trace file with DSN
* SUCCESS records from virtual alias expansion.
*/
if (state->errs != 0 || (state->flags & CLEANUP_FLAG_DISCARD) != 0) {
if (cleanup_trace_path)
(void) REMOVE(vstring_str(cleanup_trace_path));
if (REMOVE(cleanup_path))
msg_warn("remove %s: %m", cleanup_path);
}
/*
* Make sure that our queue file will not be deleted by the error handler
* AFTER we have taken responsibility for delivery. Better to deliver
* twice than to lose mail.
*/
trace_junk = cleanup_trace_path;
cleanup_trace_path = 0; /* don't delete upon error */
junk = cleanup_path;
cleanup_path = 0; /* don't delete upon error */
if (trace_junk)
vstring_free(trace_junk);
myfree(junk);
/*
* Cleanup internal state. This is simply complementary to the
* initializations at the beginning of cleanup_open().
*/
if (msg_verbose)
msg_info("cleanup_flush: status %d", state->errs);
status = state->errs;
return (status);
}
/* cleanup_free - pay the last respects */
void cleanup_free(CLEANUP_STATE *state)
{
/*
* Emulate disconnect event. CLEANUP_FLAG_MILTER may be turned off after
* we have started.
*/
if (cleanup_milters != 0 && state->milters == 0)
milter_disc_event(cleanup_milters);
cleanup_state_free(state);
}