1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) University of Cambridge 1995 - 2018 */
6 /* Copyright (c) The Exim Maintainers 2020 */
7 /* See the file NOTICE for conditions of use and distribution. */
9 /* Functions for writing log files. The code for maintaining datestamped
10 log files was originally contributed by Tony Sheen. */
15 #define LOG_NAME_SIZE 256
16 #define MAX_SYSLOG_LEN 870
18 #define LOG_MODE_FILE 1
19 #define LOG_MODE_SYSLOG 2
21 enum { lt_main, lt_reject, lt_panic, lt_debug };
23 static uschar *log_names[] = { US"main", US"reject", US"panic", US"debug" };
27 /*************************************************
28 * Local static variables *
29 *************************************************/
31 static uschar mainlog_name[LOG_NAME_SIZE];
32 static uschar rejectlog_name[LOG_NAME_SIZE];
33 static uschar debuglog_name[LOG_NAME_SIZE];
35 static uschar *mainlog_datestamp = NULL;
36 static uschar *rejectlog_datestamp = NULL;
38 static int mainlogfd = -1;
39 static int rejectlogfd = -1;
40 static ino_t mainlog_inode = 0;
41 static ino_t rejectlog_inode = 0;
43 static uschar *panic_save_buffer = NULL;
44 static BOOL panic_recurseflag = FALSE;
46 static BOOL syslog_open = FALSE;
47 static BOOL path_inspected = FALSE;
48 static int logging_mode = LOG_MODE_FILE;
49 static uschar *file_path = US"";
51 static size_t pid_position[2];
54 /* These should be kept in-step with the private delivery error
55 number definitions in macros.h */
57 static const uschar * exim_errstrings[] = {
80 US"Exim-imposed quota",
82 US"Delivery filter process failure",
83 US"Delivery add/remove header failure",
84 US"Delivery write incomplete error",
85 US"Some expansion failed",
86 US"Failed to get gid",
87 US"Failed to get uid",
88 US"Unset or non-existent transport",
89 US"MBX length mismatch",
90 US"Lookup failed routing or in smtp tpt",
91 US"Can't match format in appendfile",
92 US"Creation outside home in appendfile",
93 US"Can't check a list; lookup defer",
95 US"Failed to start TLS session",
96 US"Mandatory TLS session not started",
97 US"Failed to chown a file",
98 US"Failed to create a pipe",
100 US"When required by client",
101 US"Used internally in smtp transport",
102 US"RCPT gave 4xx error",
103 US"MAIL gave 4xx error",
104 US"DATA gave 4xx error",
105 US"Negotiation failed for proxy configured host",
106 US"Authenticator 'other' failure",
107 US"target not supporting SMTPUTF8",
109 US"tainted filename",
111 US"Not time for routing",
112 US"Not time for local delivery",
113 US"Not time for any remote host",
114 US"Local-only delivery",
115 US"Domain in queue_domains",
116 US"Transport concurrency limit",
117 US"Event requests alternate response",
121 /************************************************/
125 return err < 0 ? exim_errstrings[-err] : CUS strerror(err);
128 /*************************************************
130 *************************************************/
132 /* The given string is split into sections according to length, or at embedded
133 newlines, and syslogged as a numbered sequence if it is overlong or if there is
134 more than one line. However, if we are running in the test harness, do not do
135 anything. (The test harness doesn't use syslog - for obvious reasons - but we
136 can get here if there is a failure to open the panic log.)
139 priority syslog priority
140 s the string to be written
146 write_syslog(int priority, const uschar *s)
151 if (!syslog_pid && LOGGING(pid))
152 s = string_sprintf("%.*s%s", (int)pid_position[0], s, s + pid_position[1]);
153 if (!syslog_timestamp)
155 len = log_timezone ? 26 : 20;
156 if (LOGGING(millisec)) len += 4;
163 if (!syslog_open && !f.running_in_test_harness)
165 # ifdef SYSLOG_LOG_PID
166 openlog(CS syslog_processname, LOG_PID|LOG_CONS, syslog_facility);
168 openlog(CS syslog_processname, LOG_CONS, syslog_facility);
174 /* First do a scan through the message in order to determine how many lines
175 it is going to end up as. Then rescan to output it. */
177 for (int pass = 0; pass < 2; pass++)
179 const uschar * ss = s;
180 for (int i = 1, tlen = len; tlen > 0; i++)
183 uschar *nlptr = Ustrchr(ss, '\n');
184 if (nlptr != NULL) plen = nlptr - ss;
185 #ifndef SYSLOG_LONG_LINES
186 if (plen > MAX_SYSLOG_LEN) plen = MAX_SYSLOG_LEN;
189 if (ss[plen] == '\n') tlen--; /* chars left */
193 else if (f.running_in_test_harness)
195 fprintf(stderr, "SYSLOG: '%.*s'\n", plen, ss);
197 fprintf(stderr, "SYSLOG: '[%d%c%d] %.*s'\n", i,
198 ss[plen] == '\n' && tlen != 0 ? '\\' : '/',
199 linecount, plen, ss);
202 syslog(priority, "%.*s", plen, ss);
204 syslog(priority, "[%d%c%d] %.*s", i,
205 ss[plen] == '\n' && tlen != 0 ? '\\' : '/',
206 linecount, plen, ss);
209 if (*ss == '\n') ss++;
216 /*************************************************
218 *************************************************/
220 /* This is called when Exim is dying as a result of something going wrong in
221 the logging, or after a log call with LOG_PANIC_DIE set. Optionally write a
222 message to debug_file or a stderr file, if they exist. Then, if in the middle
223 of accepting a message, throw it away tidily by calling receive_bomb_out();
224 this will attempt to send an SMTP response if appropriate. Passing NULL as the
225 first argument stops it trying to run the NOTQUIT ACL (which might try further
226 logging and thus cause problems). Otherwise, try to close down an outstanding
230 s1 Error message to write to debug_file and/or stderr and syslog
231 s2 Error message for any SMTP call that is in progress
232 Returns: The function does not return
236 die(uschar *s1, uschar *s2)
240 write_syslog(LOG_CRIT, s1);
241 if (debug_file) debug_printf("%s\n", s1);
242 if (log_stderr && log_stderr != debug_file)
243 fprintf(log_stderr, "%s\n", s1);
245 if (f.receive_call_bombout) receive_bomb_out(NULL, s2); /* does not return */
246 if (smtp_input) smtp_closedown(s2);
247 exim_exit(EXIT_FAILURE);
252 /*************************************************
253 * Create a log file *
254 *************************************************/
256 /* This function is called to create and open a log file. It may be called in a
257 subprocess when the original process is root.
262 The file name has been build in a working buffer, so it is permissible to
263 overwrite it temporarily if it is necessary to create the directory.
265 Returns: a file descriptor, or < 0 on failure (errno set)
269 log_create(uschar *name)
275 O_CREAT|O_APPEND|O_WRONLY, LOG_MODE);
277 /* If creation failed, attempt to build a log directory in case that is the
280 if (fd < 0 && errno == ENOENT)
283 uschar *lastslash = Ustrrchr(name, '/');
285 created = directory_make(NULL, name, LOG_DIRECTORY_MODE, FALSE);
286 DEBUG(D_any) debug_printf("%s log directory %s\n",
287 created ? "created" : "failed to create", name);
289 if (created) fd = Uopen(name,
293 O_CREAT|O_APPEND|O_WRONLY, LOG_MODE);
301 /*************************************************
302 * Create a log file as the exim user *
303 *************************************************/
305 /* This function is called when we are root to spawn an exim:exim subprocess
306 in which we can create a log file. It must be signal-safe since it is called
307 by the usr1_handler().
312 Returns: a file descriptor, or < 0 on failure (errno set)
316 log_create_as_exim(uschar *name)
318 pid_t pid = exim_fork(US"logfile-create");
322 /* In the subprocess, change uid/gid and do the creation. Return 0 from the
323 subprocess on success. If we don't check for setuid failures, then the file
324 can be created as root, so vulnerabilities which cause setuid to fail mean
325 that the Exim user can use symlinks to cause a file to be opened/created as
326 root. We always open for append, so can't nuke existing content but it would
327 still be Rather Bad. */
331 if (setgid(exim_gid) < 0)
332 die(US"exim: setgid for log-file creation failed, aborting",
333 US"Unexpected log failure, please try later");
334 if (setuid(exim_uid) < 0)
335 die(US"exim: setuid for log-file creation failed, aborting",
336 US"Unexpected log failure, please try later");
337 _exit((log_create(name) < 0)? 1 : 0);
340 /* If we created a subprocess, wait for it. If it succeeded, try the open. */
342 while (pid > 0 && waitpid(pid, &status, 0) != pid);
343 if (status == 0) fd = Uopen(name,
347 O_APPEND|O_WRONLY, LOG_MODE);
349 /* If we failed to create a subprocess, we are in a bad way. We return
350 with fd still < 0, and errno set, letting the caller handle the error. */
358 /*************************************************
360 *************************************************/
362 /* This function opens one of a number of logs, creating the log directory if
363 it does not exist. This may be called recursively on failure, in order to open
366 The directory is in the static variable file_path. This is static so that it
367 the work of sorting out the path is done just once per Exim process.
369 Exim is normally configured to avoid running as root wherever possible, the log
370 files must be owned by the non-privileged exim user. To ensure this, first try
371 an open without O_CREAT - most of the time this will succeed. If it fails, try
372 to create the file; if running as root, this must be done in a subprocess to
376 fd where to return the resulting file descriptor
377 type lt_main, lt_reject, lt_panic, or lt_debug
378 tag optional tag to include in the name (only hooked up for debug)
384 open_log(int *fd, int type, uschar *tag)
388 uschar buffer[LOG_NAME_SIZE];
390 /* The names of the log files are controlled by file_path. The panic log is
391 written to the same directory as the main and reject logs, but its name does
392 not have a datestamp. The use of datestamps is indicated by %D/%M in file_path.
393 When opening the panic log, if %D or %M is present, we remove the datestamp
394 from the generated name; if it is at the start, remove a following
395 non-alphanumeric character as well; otherwise, remove a preceding
396 non-alphanumeric character. This is definitely kludgy, but it sort of does what
397 people want, I hope. */
399 ok = string_format(buffer, sizeof(buffer), CS file_path, log_names[type]);
401 /* Save the name of the mainlog for rollover processing. Without a datestamp,
402 it gets statted to see if it has been cycled. With a datestamp, the datestamp
403 will be compared. The static slot for saving it is the same size as buffer,
404 and the text has been checked above to fit, so this use of strcpy() is OK. */
408 Ustrcpy(mainlog_name, buffer);
409 if (string_datestamp_offset > 0)
410 mainlog_datestamp = mainlog_name + string_datestamp_offset;
413 /* Ditto for the reject log */
415 else if (type == lt_reject)
417 Ustrcpy(rejectlog_name, buffer);
418 if (string_datestamp_offset > 0)
419 rejectlog_datestamp = rejectlog_name + string_datestamp_offset;
422 /* and deal with the debug log (which keeps the datestamp, but does not
425 else if (type == lt_debug)
427 Ustrcpy(debuglog_name, buffer);
430 /* this won't change the offset of the datestamp */
431 ok2 = string_format(buffer, sizeof(buffer), "%s%s",
434 Ustrcpy(debuglog_name, buffer);
438 /* Remove any datestamp if this is the panic log. This is rare, so there's no
439 need to optimize getting the datestamp length. We remove one non-alphanumeric
440 char afterwards if at the start, otherwise one before. */
442 else if (string_datestamp_offset >= 0)
444 uschar * from = buffer + string_datestamp_offset;
445 uschar * to = from + string_datestamp_length;
447 if (from == buffer || from[-1] == '/')
449 if (!isalnum(*to)) to++;
452 if (!isalnum(from[-1])) from--;
454 /* This copy is ok, because we know that to is a substring of from. But
455 due to overlap we must use memmove() not Ustrcpy(). */
456 memmove(from, to, Ustrlen(to)+1);
459 /* If the file name is too long, it is an unrecoverable disaster */
462 die(US"exim: log file path too long: aborting",
463 US"Logging failure; please try later");
465 /* We now have the file name. Try to open an existing file. After a successful
466 open, arrange for automatic closure on exec(), and then return. */
472 O_APPEND|O_WRONLY, LOG_MODE);
477 (void)fcntl(*fd, F_SETFD, fcntl(*fd, F_GETFD) | FD_CLOEXEC);
482 /* Open was not successful: try creating the file. If this is a root process,
483 we must do the creating in a subprocess set to exim:exim in order to ensure
484 that the file is created with the right ownership. Otherwise, there can be a
485 race if another Exim process is trying to write to the log at the same time.
486 The use of SIGUSR1 by the exiwhat utility can provoke a lot of simultaneous
491 /* If we are already running as the Exim user (even if that user is root),
492 we can go ahead and create in the current process. */
494 if (euid == exim_uid) *fd = log_create(buffer);
496 /* Otherwise, if we are root, do the creation in an exim:exim subprocess. If we
497 are neither exim nor root, creation is not attempted. */
499 else if (euid == root_uid) *fd = log_create_as_exim(buffer);
501 /* If we now have an open file, set the close-on-exec flag and return. */
506 (void)fcntl(*fd, F_SETFD, fcntl(*fd, F_GETFD) | FD_CLOEXEC);
511 /* Creation failed. There are some circumstances in which we get here when
512 the effective uid is not root or exim, which is the problem. (For example, a
513 non-setuid binary with log_arguments set, called in certain ways.) Rather than
514 just bombing out, force the log to stderr and carry on if stderr is available.
517 if (euid != root_uid && euid != exim_uid && log_stderr)
519 *fd = fileno(log_stderr);
523 /* Otherwise this is a disaster. This call is deliberately ONLY to the panic
524 log. If possible, save a copy of the original line that was being logged. If we
525 are recursing (can't open the panic log either), the pointer will already be
526 set. Also, when we had to use a subprocess for the create we didn't retrieve
527 errno from it, so get the error from the open attempt above (which is often
528 meaningful enough, so leave it). */
530 if (!panic_save_buffer)
531 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
532 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
534 log_write(0, LOG_PANIC_DIE, "Cannot open %s log file \"%s\": %s: "
535 "euid=%d egid=%d", log_names[type], buffer, strerror(errno), euid, getegid());
543 if (type == lt_debug) unlink(CS debuglog_name);
548 /*************************************************
549 * Add configuration file info to log line *
550 *************************************************/
552 /* This is put in a function because it's needed twice (once for debugging,
556 ptr pointer to the end of the line we are building
559 Returns: updated pointer
563 log_config_info(gstring * g, int flags)
565 g = string_cat(g, US"Exim configuration error");
567 if (flags & (LOG_CONFIG_FOR & ~LOG_CONFIG))
568 return string_cat(g, US" for ");
570 if (flags & (LOG_CONFIG_IN & ~LOG_CONFIG))
571 g = string_fmt_append(g, " in line %d of %s", config_lineno, config_filename);
573 return string_catn(g, US":\n ", 4);
577 /*************************************************
578 * A write() operation failed *
579 *************************************************/
581 /* This function is called when write() fails on anything other than the panic
582 log, which can happen if a disk gets full or a file gets too large or whatever.
583 We try to save the relevant message in the panic_save buffer before crashing
586 The potential invoker should probably not call us for EINTR -1 writes. But
587 otherwise, short writes are bad as we don't do non-blocking writes to fds
588 subject to flow control. (If we do, that's new and the logic of this should
592 name the name of the log being written
593 length the string length being written
594 rc the return value from write()
596 Returns: does not return
600 log_write_failed(uschar *name, int length, int rc)
602 int save_errno = errno;
604 if (!panic_save_buffer)
605 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
606 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
608 log_write(0, LOG_PANIC_DIE, "failed to write to %s: length=%d result=%d "
609 "errno=%d (%s)", name, length, rc, save_errno,
610 (save_errno == 0)? "write incomplete" : strerror(save_errno));
616 /*************************************************
617 * Write to an fd, retrying after signals *
618 *************************************************/
620 /* Basic write to fd for logs, handling EINTR.
623 fd the fd to write to
624 buf the string to write
625 length the string length being written
628 length actually written, persisting an errno from write()
631 write_to_fd_buf(int fd, const uschar *buf, size_t length)
634 size_t total_written = 0;
635 const uschar *p = buf;
636 size_t left = length;
640 wrote = write(fd, p, left);
641 if (wrote == (ssize_t)-1)
643 if (errno == EINTR) continue;
646 total_written += wrote;
655 return total_written;
663 int sep = ':'; /* Fixed separator - outside use */
665 const uschar *tt = US LOG_FILE_PATH;
666 while ((t = string_nextinlist(&tt, &sep, log_buffer, LOG_BUFFER_SIZE)))
668 if (Ustrcmp(t, "syslog") == 0 || t[0] == 0) continue;
669 file_path = string_copy(t);
678 if (mainlogfd < 0) return;
679 (void)close(mainlogfd);
684 /*************************************************
685 * Write message to log file *
686 *************************************************/
688 /* Exim can be configured to log to local files, or use syslog, or both. This
689 is controlled by the setting of log_file_path. The following cases are
692 log_file_path = "" write files in the spool/log directory
693 log_file_path = "xxx" write files in the xxx directory
694 log_file_path = "syslog" write to syslog
695 log_file_path = "syslog : xxx" write to syslog and to files (any order)
697 The message always gets '\n' added on the end of it, since more than one
698 process may be writing to the log at once and we don't want intermingling to
699 happen in the middle of lines. To be absolutely sure of this we write the data
700 into a private buffer and then put it out in a single write() call.
702 The flags determine which log(s) the message is written to, or for syslogging,
703 which priority to use, and in the case of the panic log, whether the process
704 should die afterwards.
706 The variable really_exim is TRUE only when exim is running in privileged state
707 (i.e. not with a changed configuration or with testing options such as -brw).
708 If it is not, don't try to write to the log because permission will probably be
711 Avoid actually writing to the logs when exim is called with -bv or -bt to
712 test an address, but take other actions, such as panicking.
714 In Exim proper, the buffer for building the message is got at start-up, so that
715 nothing gets done if it can't be got. However, some functions that are also
716 used in utilities occasionally obey log_write calls in error situations, and it
717 is simplest to put a single malloc() here rather than put one in each utility.
718 Malloc is used directly because the store functions may call log_write().
720 If a message_id exists, we include it after the timestamp.
723 selector write to main log or LOG_INFO only if this value is zero, or if
724 its bit is set in log_selector[0]
725 flags each bit indicates some independent action:
726 LOG_SENDER add raw sender to the message
727 LOG_RECIPIENTS add raw recipients list to message
728 LOG_CONFIG add "Exim configuration error"
729 LOG_CONFIG_FOR add " for " instead of ":\n "
730 LOG_CONFIG_IN add " in line x[ of file y]"
731 LOG_MAIN write to main log or syslog LOG_INFO
732 LOG_REJECT write to reject log or syslog LOG_NOTICE
733 LOG_PANIC write to panic log or syslog LOG_ALERT
734 LOG_PANIC_DIE write to panic log or LOG_ALERT and then crash
735 format a printf() format
736 ... arguments for format
742 log_write(unsigned int selector, int flags, const char *format, ...)
746 gstring gs = { .size = LOG_BUFFER_SIZE-1, .ptr = 0, .s = log_buffer };
750 /* If panic_recurseflag is set, we have failed to open the panic log. This is
751 the ultimate disaster. First try to write the message to a debug file and/or
752 stderr and also to syslog. If panic_save_buffer is not NULL, it contains the
753 original log line that caused the problem. Afterwards, expire. */
755 if (panic_recurseflag)
757 uschar *extra = panic_save_buffer ? panic_save_buffer : US"";
758 if (debug_file) debug_printf("%s%s", extra, log_buffer);
759 if (log_stderr && log_stderr != debug_file)
760 fprintf(log_stderr, "%s%s", extra, log_buffer);
761 if (*extra) write_syslog(LOG_CRIT, extra);
762 write_syslog(LOG_CRIT, log_buffer);
763 die(US"exim: could not open panic log - aborting: see message(s) above",
764 US"Unexpected log failure, please try later");
767 /* Ensure we have a buffer (see comment above); this should never be obeyed
768 when running Exim proper, only when running utilities. */
771 if (!(log_buffer = US malloc(LOG_BUFFER_SIZE)))
773 fprintf(stderr, "exim: failed to get store for log buffer\n");
774 exim_exit(EXIT_FAILURE);
777 /* If we haven't already done so, inspect the setting of log_file_path to
778 determine whether to log to files and/or to syslog. Bits in logging_mode
779 control this, and for file logging, the path must end up in file_path. This
780 variable must be in permanent store because it may be required again later in
785 BOOL multiple = FALSE;
786 int old_pool = store_pool;
788 store_pool = POOL_PERM;
790 /* If nothing has been set, don't waste effort... the default values for the
791 statics are file_path="" and logging_mode = LOG_MODE_FILE. */
795 int sep = ':'; /* Fixed separator - outside use */
797 const uschar *ss = log_file_path;
800 while ((s = string_nextinlist(&ss, &sep, log_buffer, LOG_BUFFER_SIZE)))
802 if (Ustrcmp(s, "syslog") == 0)
803 logging_mode |= LOG_MODE_SYSLOG;
804 else if (logging_mode & LOG_MODE_FILE)
808 logging_mode |= LOG_MODE_FILE;
810 /* If a non-empty path is given, use it */
813 file_path = string_copy(s);
815 /* If the path is empty, we want to use the first non-empty, non-
816 syslog item in LOG_FILE_PATH, if there is one, since the value of
817 log_file_path may have been set at runtime. If there is no such item,
818 use the ultimate default in the spool directory. */
821 set_file_path(); /* Empty item in log_file_path */
822 } /* First non-syslog item in log_file_path */
823 } /* Scan of log_file_path */
826 /* If no modes have been selected, it is a major disaster */
828 if (logging_mode == 0)
829 die(US"Neither syslog nor file logging set in log_file_path",
830 US"Unexpected logging failure");
832 /* Set up the ultimate default if necessary. Then revert to the old store
833 pool, and record that we've sorted out the path. */
835 if (logging_mode & LOG_MODE_FILE && !file_path[0])
836 file_path = string_sprintf("%s/log/%%slog", spool_directory);
837 store_pool = old_pool;
838 path_inspected = TRUE;
840 /* If more than one file path was given, log a complaint. This recursive call
841 should work since we have now set up the routing. */
844 log_write(0, LOG_MAIN|LOG_PANIC,
845 "More than one path given in log_file_path: using %s", file_path);
848 /* If debugging, show all log entries, but don't show headers. Do it all
849 in one go so that it doesn't get split when multi-processing. */
855 g = string_catn(&gs, US"LOG:", 4);
857 /* Show the selector that was passed into the call. */
859 for (i = 0; i < log_options_count; i++)
861 unsigned int bitnum = log_options[i].bit;
862 if (bitnum < BITWORDSIZE && selector == BIT(bitnum))
863 g = string_fmt_append(g, " %s", log_options[i].name);
866 g = string_fmt_append(g, "%s%s%s%s\n ",
867 flags & LOG_MAIN ? " MAIN" : "",
868 flags & LOG_PANIC ? " PANIC" : "",
869 (flags & LOG_PANIC_DIE) == LOG_PANIC_DIE ? " DIE" : "",
870 flags & LOG_REJECT ? " REJECT" : "");
872 if (flags & LOG_CONFIG) g = log_config_info(g, flags);
874 /* We want to be able to log tainted info, but log_buffer is directly
875 malloc'd. So use deliberately taint-nonchecking routines to build into
876 it, trusting that we will never expand the results. */
878 va_start(ap, format);
880 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
883 g = string_cat(g, US"**** log string overflowed log buffer ****");
887 g->size = LOG_BUFFER_SIZE;
888 g = string_catn(g, US"\n", 1);
889 debug_printf("%s", string_from_gstring(g));
891 gs.size = LOG_BUFFER_SIZE-1; /* Having used the buffer for debug output, */
892 gs.ptr = 0; /* reset it for the real use. */
895 /* If no log file is specified, we are in a mess. */
897 if (!(flags & (LOG_MAIN|LOG_PANIC|LOG_REJECT)))
898 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "log_write called with no log "
901 /* There are some weird circumstances in which logging is disabled. */
903 if (f.disable_logging)
905 DEBUG(D_any) debug_printf("log writing disabled\n");
906 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
910 /* Handle disabled reject log */
912 if (!write_rejectlog) flags &= ~LOG_REJECT;
914 /* Create the main message in the log buffer. Do not include the message id
915 when called by a utility. */
917 g = string_fmt_append(&gs, "%s ", tod_stamp(tod_log));
921 if (!syslog_pid) pid_position[0] = g->ptr; /* remember begin … */
922 g = string_fmt_append(g, "[%d] ", (int)getpid());
923 if (!syslog_pid) pid_position[1] = g->ptr; /* … and end+1 of the PID */
926 if (f.really_exim && message_id[0] != 0)
927 g = string_fmt_append(g, "%s ", message_id);
929 if (flags & LOG_CONFIG)
930 g = log_config_info(g, flags);
932 va_start(ap, format);
936 /* We want to be able to log tainted info, but log_buffer is directly
937 malloc'd. So use deliberately taint-nonchecking routines to build into
938 it, trusting that we will never expand the results. */
940 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
943 g = string_cat(g, US"**** log string overflowed log buffer ****\n");
948 /* Add the raw, unrewritten, sender to the message if required. This is done
949 this way because it kind of fits with LOG_RECIPIENTS. */
951 if ( flags & LOG_SENDER
952 && g->ptr < LOG_BUFFER_SIZE - 10 - Ustrlen(raw_sender))
953 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " from <%s>", raw_sender);
955 /* Add list of recipients to the message if required; the raw list,
956 before rewriting, was saved in raw_recipients. There may be none, if an ACL
957 discarded them all. */
959 if ( flags & LOG_RECIPIENTS
960 && g->ptr < LOG_BUFFER_SIZE - 6
961 && raw_recipients_count > 0)
964 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " for", NULL);
965 for (i = 0; i < raw_recipients_count; i++)
967 uschar * s = raw_recipients[i];
968 if (LOG_BUFFER_SIZE - g->ptr < Ustrlen(s) + 3) break;
969 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " %s", s);
973 g = string_catn(g, US"\n", 1);
974 string_from_gstring(g);
976 /* Handle loggable errors when running a utility, or when address testing.
977 Write to log_stderr unless debugging (when it will already have been written),
978 or unless there is no log_stderr (expn called from daemon, for example). */
980 if (!f.really_exim || f.log_testing_mode)
984 && (selector == 0 || (selector & log_selector[0]) != 0)
987 fprintf(log_stderr, "LOG: %s", CS(log_buffer + 20)); /* no timestamp */
989 fprintf(log_stderr, "%s", CS log_buffer);
991 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
995 /* Handle the main log. We know that either syslog or file logging (or both) is
996 set up. A real file gets left open during reception or delivery once it has
997 been opened, but we don't want to keep on writing to it for too long after it
998 has been renamed. Therefore, do a stat() and see if the inode has changed, and
1001 if ( flags & LOG_MAIN
1002 && (!selector || selector & log_selector[0]))
1004 if ( logging_mode & LOG_MODE_SYSLOG
1005 && (syslog_duplication || !(flags & (LOG_REJECT|LOG_PANIC))))
1006 write_syslog(LOG_INFO, log_buffer);
1008 if (logging_mode & LOG_MODE_FILE)
1010 struct stat statbuf;
1012 /* Check for a change to the mainlog file name when datestamping is in
1013 operation. This happens at midnight, at which point we want to roll over
1014 the file. Closing it has the desired effect. */
1016 if (mainlog_datestamp)
1018 uschar *nowstamp = tod_stamp(string_datestamp_type);
1019 if (Ustrncmp (mainlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1021 (void)close(mainlogfd); /* Close the file */
1022 mainlogfd = -1; /* Clear the file descriptor */
1023 mainlog_inode = 0; /* Unset the inode */
1024 mainlog_datestamp = NULL; /* Clear the datestamp */
1028 /* Otherwise, we want to check whether the file has been renamed by a
1029 cycling script. This could be "if else", but for safety's sake, leave it as
1030 "if" so that renaming the log starts a new file even when datestamping is
1034 if (Ustat(mainlog_name, &statbuf) < 0 || statbuf.st_ino != mainlog_inode)
1037 /* If the log is closed, open it. Then write the line. */
1041 open_log(&mainlogfd, lt_main, NULL); /* No return on error */
1042 if (fstat(mainlogfd, &statbuf) >= 0) mainlog_inode = statbuf.st_ino;
1045 /* Failing to write to the log is disastrous */
1047 written_len = write_to_fd_buf(mainlogfd, g->s, g->ptr);
1048 if (written_len != g->ptr)
1050 log_write_failed(US"main log", g->ptr, written_len);
1051 /* That function does not return */
1056 /* Handle the log for rejected messages. This can be globally disabled, in
1057 which case the flags are altered above. If there are any header lines (i.e. if
1058 the rejection is happening after the DATA phase), log the recipients and the
1061 if (flags & LOG_REJECT)
1063 if (header_list && LOGGING(rejected_header))
1068 if (recipients_count > 0)
1070 /* List the sender */
1072 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1073 "Envelope-from: <%s>\n", sender_address);
1076 /* List up to 5 recipients */
1078 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1079 "Envelope-to: <%s>\n", recipients_list[0].address);
1082 for (i = 1; i < recipients_count && i < 5; i++)
1084 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1085 " <%s>\n", recipients_list[i].address);
1089 if (i < recipients_count)
1091 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " ...\n", NULL);
1096 /* A header with a NULL text is an unfilled in Received: header */
1098 for (header_line * h = header_list; h; h = h->next) if (h->text)
1100 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1101 "%c %s", h->type, h->text);
1104 else /* Buffer is full; truncate */
1106 g->ptr -= 100; /* For message and separator */
1107 if (g->s[g->ptr-1] == '\n') g->ptr--;
1108 g = string_cat(g, US"\n*** truncated ***\n");
1114 /* Write to syslog or to a log file */
1116 if ( logging_mode & LOG_MODE_SYSLOG
1117 && (syslog_duplication || !(flags & LOG_PANIC)))
1118 write_syslog(LOG_NOTICE, string_from_gstring(g));
1120 /* Check for a change to the rejectlog file name when datestamping is in
1121 operation. This happens at midnight, at which point we want to roll over
1122 the file. Closing it has the desired effect. */
1124 if (logging_mode & LOG_MODE_FILE)
1126 struct stat statbuf;
1128 if (rejectlog_datestamp)
1130 uschar *nowstamp = tod_stamp(string_datestamp_type);
1131 if (Ustrncmp (rejectlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1133 (void)close(rejectlogfd); /* Close the file */
1134 rejectlogfd = -1; /* Clear the file descriptor */
1135 rejectlog_inode = 0; /* Unset the inode */
1136 rejectlog_datestamp = NULL; /* Clear the datestamp */
1140 /* Otherwise, we want to check whether the file has been renamed by a
1141 cycling script. This could be "if else", but for safety's sake, leave it as
1142 "if" so that renaming the log starts a new file even when datestamping is
1145 if (rejectlogfd >= 0)
1146 if (Ustat(rejectlog_name, &statbuf) < 0 ||
1147 statbuf.st_ino != rejectlog_inode)
1149 (void)close(rejectlogfd);
1151 rejectlog_inode = 0;
1154 /* Open the file if necessary, and write the data */
1156 if (rejectlogfd < 0)
1158 open_log(&rejectlogfd, lt_reject, NULL); /* No return on error */
1159 if (fstat(rejectlogfd, &statbuf) >= 0) rejectlog_inode = statbuf.st_ino;
1162 written_len = write_to_fd_buf(rejectlogfd, g->s, g->ptr);
1163 if (written_len != g->ptr)
1165 log_write_failed(US"reject log", g->ptr, written_len);
1166 /* That function does not return */
1172 /* Handle the panic log, which is not kept open like the others. If it fails to
1173 open, there will be a recursive call to log_write(). We detect this above and
1174 attempt to write to the system log as a last-ditch try at telling somebody. In
1175 all cases except mua_wrapper, try to write to log_stderr. */
1177 if (flags & LOG_PANIC)
1179 if (log_stderr && log_stderr != debug_file && !mua_wrapper)
1180 fprintf(log_stderr, "%s", CS string_from_gstring(g));
1182 if (logging_mode & LOG_MODE_SYSLOG)
1183 write_syslog(LOG_ALERT, log_buffer);
1185 /* If this panic logging was caused by a failure to open the main log,
1186 the original log line is in panic_save_buffer. Make an attempt to write it. */
1188 if (logging_mode & LOG_MODE_FILE)
1190 panic_recurseflag = TRUE;
1191 open_log(&paniclogfd, lt_panic, NULL); /* Won't return on failure */
1192 panic_recurseflag = FALSE;
1194 if (panic_save_buffer)
1195 (void) write(paniclogfd, panic_save_buffer, Ustrlen(panic_save_buffer));
1197 written_len = write_to_fd_buf(paniclogfd, g->s, g->ptr);
1198 if (written_len != g->ptr)
1200 int save_errno = errno;
1201 write_syslog(LOG_CRIT, log_buffer);
1202 sprintf(CS log_buffer, "write failed on panic log: length=%d result=%d "
1203 "errno=%d (%s)", g->ptr, (int)written_len, save_errno, strerror(save_errno));
1204 write_syslog(LOG_CRIT, string_from_gstring(g));
1205 flags |= LOG_PANIC_DIE;
1208 (void)close(paniclogfd);
1211 /* Give up if the DIE flag is set */
1213 if ((flags & LOG_PANIC_DIE) != LOG_PANIC)
1214 die(NULL, US"Unexpected failure, please try later");
1220 /*************************************************
1221 * Close any open log files *
1222 *************************************************/
1228 { (void)close(mainlogfd); mainlogfd = -1; }
1229 if (rejectlogfd >= 0)
1230 { (void)close(rejectlogfd); rejectlogfd = -1; }
1232 syslog_open = FALSE;
1237 /*************************************************
1238 * Multi-bit set or clear *
1239 *************************************************/
1241 /* These functions take a list of bit indexes (terminated by -1) and
1242 clear or set the corresponding bits in the selector.
1245 selector address of the bit string
1246 selsize number of words in the bit string
1247 bits list of bits to set
1251 bits_clear(unsigned int *selector, size_t selsize, int *bits)
1253 for(; *bits != -1; ++bits)
1254 BIT_CLEAR(selector, selsize, *bits);
1258 bits_set(unsigned int *selector, size_t selsize, int *bits)
1260 for(; *bits != -1; ++bits)
1261 BIT_SET(selector, selsize, *bits);
1266 /*************************************************
1267 * Decode bit settings for log/debug *
1268 *************************************************/
1270 /* This function decodes a string containing bit settings in the form of +name
1271 and/or -name sequences, and sets/unsets bits in a bit string accordingly. It
1272 also recognizes a numeric setting of the form =<number>, but this is not
1273 intended for user use. It's an easy way for Exim to pass the debug settings
1274 when it is re-exec'ed.
1276 The option table is a list of names and bit indexes. The index -1
1277 means "set all bits, except for those listed in notall". The notall
1278 list is terminated by -1.
1280 The action taken for bad values varies depending upon why we're here.
1281 For log messages, or if the debugging is triggered from config, then we write
1282 to the log on the way out. For debug setting triggered from the command-line,
1283 we treat it as an unknown option: error message to stderr and die.
1286 selector address of the bit string
1287 selsize number of words in the bit string
1288 notall list of bits to exclude from "all"
1289 string the configured string
1290 options the table of option names
1292 which "log" or "debug"
1293 flags DEBUG_FROM_CONFIG
1295 Returns: nothing on success - bomb out on failure
1299 decode_bits(unsigned int *selector, size_t selsize, int *notall,
1300 uschar *string, bit_table *options, int count, uschar *which, int flags)
1303 if (!string) return;
1307 char *end; /* Not uschar */
1308 memset(selector, 0, sizeof(*selector)*selsize);
1309 *selector = strtoul(CS string+1, &end, 0);
1311 errmsg = string_sprintf("malformed numeric %s_selector setting: %s", which,
1316 /* Handle symbolic setting */
1323 bit_table *start, *end;
1325 Uskip_whitespace(&string);
1326 if (!*string) return;
1328 if (*string != '+' && *string != '-')
1330 errmsg = string_sprintf("malformed %s_selector setting: "
1331 "+ or - expected but found \"%s\"", which, string);
1335 adding = *string++ == '+';
1337 while (isalnum(*string) || *string == '_') string++;
1341 end = options + count;
1345 bit_table *middle = start + (end - start)/2;
1346 int c = Ustrncmp(s, middle->name, len);
1348 if (middle->name[len] != 0) c = -1; else
1350 unsigned int bit = middle->bit;
1356 memset(selector, -1, sizeof(*selector)*selsize);
1357 bits_clear(selector, selsize, notall);
1360 memset(selector, 0, sizeof(*selector)*selsize);
1363 BIT_SET(selector, selsize, bit);
1365 BIT_CLEAR(selector, selsize, bit);
1367 break; /* Out of loop to match selector name */
1369 if (c < 0) end = middle; else start = middle + 1;
1370 } /* Loop to match selector name */
1374 errmsg = string_sprintf("unknown %s_selector setting: %c%.*s", which,
1375 adding? '+' : '-', len, s);
1378 } /* Loop for selector names */
1380 /* Handle disasters */
1383 if (Ustrcmp(which, "debug") == 0)
1385 if (flags & DEBUG_FROM_CONFIG)
1387 log_write(0, LOG_CONFIG|LOG_PANIC, "%s", errmsg);
1390 fprintf(stderr, "exim: %s\n", errmsg);
1393 else log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "%s", errmsg);
1398 /*************************************************
1399 * Activate a debug logfile (late) *
1400 *************************************************/
1402 /* Normally, debugging is activated from the command-line; it may be useful
1403 within the configuration to activate debugging later, based on certain
1404 conditions. If debugging is already in progress, we return early, no action
1405 taken (besides debug-logging that we wanted debug-logging).
1407 Failures in options are not fatal but will result in paniclog entries for the
1410 The first use of this is in ACL logic, "control = debug/tag=foo/opts=+expand"
1411 which can be combined with conditions, etc, to activate extra logging only
1412 for certain sources. The second use is inetd wait mode debug preservation. */
1415 debug_logging_activate(uschar *tag_name, uschar *opts)
1421 debug_printf("DEBUGGING ACTIVATED FROM WITHIN CONFIG.\n"
1422 "DEBUG: Tag=\"%s\" opts=\"%s\"\n", tag_name, opts ? opts : US"");
1426 if (tag_name != NULL && (Ustrchr(tag_name, '/') != NULL))
1428 log_write(0, LOG_MAIN|LOG_PANIC, "debug tag may not contain a '/' in: %s",
1433 debug_selector = D_default;
1435 decode_bits(&debug_selector, 1, debug_notall, opts,
1436 debug_options, debug_options_count, US"debug", DEBUG_FROM_CONFIG);
1438 /* When activating from a transport process we may never have logged at all
1439 resulting in certain setup not having been done. Hack this for now so we
1440 do not segfault; note that nondefault log locations will not work */
1442 if (!*file_path) set_file_path();
1444 open_log(&fd, lt_debug, tag_name);
1447 debug_file = fdopen(fd, "w");
1449 log_write(0, LOG_MAIN|LOG_PANIC, "unable to open debug log");
1454 debug_logging_stop(void)
1456 if (!debug_file || !debuglog_name[0]) return;
1461 unlink_log(lt_debug);