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",
110 US"Not time for routing",
111 US"Not time for local delivery",
112 US"Not time for any remote host",
113 US"Local-only delivery",
114 US"Domain in queue_domains",
115 US"Transport concurrency limit",
116 US"Event requests alternate response",
120 /************************************************/
124 return err < 0 ? exim_errstrings[-err] : CUS strerror(err);
127 /*************************************************
129 *************************************************/
131 /* The given string is split into sections according to length, or at embedded
132 newlines, and syslogged as a numbered sequence if it is overlong or if there is
133 more than one line. However, if we are running in the test harness, do not do
134 anything. (The test harness doesn't use syslog - for obvious reasons - but we
135 can get here if there is a failure to open the panic log.)
138 priority syslog priority
139 s the string to be written
145 write_syslog(int priority, const uschar *s)
150 if (!syslog_pid && LOGGING(pid))
151 s = string_sprintf("%.*s%s", (int)pid_position[0], s, s + pid_position[1]);
152 if (!syslog_timestamp)
154 len = log_timezone ? 26 : 20;
155 if (LOGGING(millisec)) len += 4;
162 if (!syslog_open && !f.running_in_test_harness)
164 # ifdef SYSLOG_LOG_PID
165 openlog(CS syslog_processname, LOG_PID|LOG_CONS, syslog_facility);
167 openlog(CS syslog_processname, LOG_CONS, syslog_facility);
173 /* First do a scan through the message in order to determine how many lines
174 it is going to end up as. Then rescan to output it. */
176 for (int pass = 0; pass < 2; pass++)
178 const uschar * ss = s;
179 for (int i = 1, tlen = len; tlen > 0; i++)
182 uschar *nlptr = Ustrchr(ss, '\n');
183 if (nlptr != NULL) plen = nlptr - ss;
184 #ifndef SYSLOG_LONG_LINES
185 if (plen > MAX_SYSLOG_LEN) plen = MAX_SYSLOG_LEN;
188 if (ss[plen] == '\n') tlen--; /* chars left */
192 else if (f.running_in_test_harness)
194 fprintf(stderr, "SYSLOG: '%.*s'\n", plen, ss);
196 fprintf(stderr, "SYSLOG: '[%d%c%d] %.*s'\n", i,
197 ss[plen] == '\n' && tlen != 0 ? '\\' : '/',
198 linecount, plen, ss);
201 syslog(priority, "%.*s", plen, ss);
203 syslog(priority, "[%d%c%d] %.*s", i,
204 ss[plen] == '\n' && tlen != 0 ? '\\' : '/',
205 linecount, plen, ss);
208 if (*ss == '\n') ss++;
215 /*************************************************
217 *************************************************/
219 /* This is called when Exim is dying as a result of something going wrong in
220 the logging, or after a log call with LOG_PANIC_DIE set. Optionally write a
221 message to debug_file or a stderr file, if they exist. Then, if in the middle
222 of accepting a message, throw it away tidily by calling receive_bomb_out();
223 this will attempt to send an SMTP response if appropriate. Passing NULL as the
224 first argument stops it trying to run the NOTQUIT ACL (which might try further
225 logging and thus cause problems). Otherwise, try to close down an outstanding
229 s1 Error message to write to debug_file and/or stderr and syslog
230 s2 Error message for any SMTP call that is in progress
231 Returns: The function does not return
235 die(uschar *s1, uschar *s2)
239 write_syslog(LOG_CRIT, s1);
240 if (debug_file) debug_printf("%s\n", s1);
241 if (log_stderr && log_stderr != debug_file)
242 fprintf(log_stderr, "%s\n", s1);
244 if (f.receive_call_bombout) receive_bomb_out(NULL, s2); /* does not return */
245 if (smtp_input) smtp_closedown(s2);
246 exim_exit(EXIT_FAILURE);
251 /*************************************************
252 * Create a log file *
253 *************************************************/
255 /* This function is called to create and open a log file. It may be called in a
256 subprocess when the original process is root.
261 The file name has been build in a working buffer, so it is permissible to
262 overwrite it temporarily if it is necessary to create the directory.
264 Returns: a file descriptor, or < 0 on failure (errno set)
268 log_create(uschar *name)
274 O_CREAT|O_APPEND|O_WRONLY, LOG_MODE);
276 /* If creation failed, attempt to build a log directory in case that is the
279 if (fd < 0 && errno == ENOENT)
282 uschar *lastslash = Ustrrchr(name, '/');
284 created = directory_make(NULL, name, LOG_DIRECTORY_MODE, FALSE);
285 DEBUG(D_any) debug_printf("%s log directory %s\n",
286 created ? "created" : "failed to create", name);
288 if (created) fd = Uopen(name,
292 O_CREAT|O_APPEND|O_WRONLY, LOG_MODE);
300 /*************************************************
301 * Create a log file as the exim user *
302 *************************************************/
304 /* This function is called when we are root to spawn an exim:exim subprocess
305 in which we can create a log file. It must be signal-safe since it is called
306 by the usr1_handler().
311 Returns: a file descriptor, or < 0 on failure (errno set)
315 log_create_as_exim(uschar *name)
317 pid_t pid = exim_fork(US"logfile-create");
321 /* In the subprocess, change uid/gid and do the creation. Return 0 from the
322 subprocess on success. If we don't check for setuid failures, then the file
323 can be created as root, so vulnerabilities which cause setuid to fail mean
324 that the Exim user can use symlinks to cause a file to be opened/created as
325 root. We always open for append, so can't nuke existing content but it would
326 still be Rather Bad. */
330 if (setgid(exim_gid) < 0)
331 die(US"exim: setgid for log-file creation failed, aborting",
332 US"Unexpected log failure, please try later");
333 if (setuid(exim_uid) < 0)
334 die(US"exim: setuid for log-file creation failed, aborting",
335 US"Unexpected log failure, please try later");
336 _exit((log_create(name) < 0)? 1 : 0);
339 /* If we created a subprocess, wait for it. If it succeeded, try the open. */
341 while (pid > 0 && waitpid(pid, &status, 0) != pid);
342 if (status == 0) fd = Uopen(name,
346 O_APPEND|O_WRONLY, LOG_MODE);
348 /* If we failed to create a subprocess, we are in a bad way. We return
349 with fd still < 0, and errno set, letting the caller handle the error. */
357 /*************************************************
359 *************************************************/
361 /* This function opens one of a number of logs, creating the log directory if
362 it does not exist. This may be called recursively on failure, in order to open
365 The directory is in the static variable file_path. This is static so that it
366 the work of sorting out the path is done just once per Exim process.
368 Exim is normally configured to avoid running as root wherever possible, the log
369 files must be owned by the non-privileged exim user. To ensure this, first try
370 an open without O_CREAT - most of the time this will succeed. If it fails, try
371 to create the file; if running as root, this must be done in a subprocess to
375 fd where to return the resulting file descriptor
376 type lt_main, lt_reject, lt_panic, or lt_debug
377 tag optional tag to include in the name (only hooked up for debug)
383 open_log(int *fd, int type, uschar *tag)
387 uschar buffer[LOG_NAME_SIZE];
389 /* The names of the log files are controlled by file_path. The panic log is
390 written to the same directory as the main and reject logs, but its name does
391 not have a datestamp. The use of datestamps is indicated by %D/%M in file_path.
392 When opening the panic log, if %D or %M is present, we remove the datestamp
393 from the generated name; if it is at the start, remove a following
394 non-alphanumeric character as well; otherwise, remove a preceding
395 non-alphanumeric character. This is definitely kludgy, but it sort of does what
396 people want, I hope. */
398 ok = string_format(buffer, sizeof(buffer), CS file_path, log_names[type]);
403 /* Save the name of the mainlog for rollover processing. Without a datestamp,
404 it gets statted to see if it has been cycled. With a datestamp, the datestamp
405 will be compared. The static slot for saving it is the same size as buffer,
406 and the text has been checked above to fit, so this use of strcpy() is OK. */
407 Ustrcpy(mainlog_name, buffer);
408 if (string_datestamp_offset > 0)
409 mainlog_datestamp = mainlog_name + string_datestamp_offset;
411 /* Ditto for the reject log */
412 Ustrcpy(rejectlog_name, buffer);
413 if (string_datestamp_offset > 0)
414 rejectlog_datestamp = rejectlog_name + string_datestamp_offset;
416 /* and deal with the debug log (which keeps the datestamp, but does not
418 Ustrcpy(debuglog_name, buffer);
421 /* this won't change the offset of the datestamp */
422 ok2 = string_format(buffer, sizeof(buffer), "%s%s",
425 Ustrcpy(debuglog_name, buffer);
428 /* Remove any datestamp if this is the panic log. This is rare, so there's no
429 need to optimize getting the datestamp length. We remove one non-alphanumeric
430 char afterwards if at the start, otherwise one before. */
431 if (string_datestamp_offset >= 0)
433 uschar * from = buffer + string_datestamp_offset;
434 uschar * to = from + string_datestamp_length;
436 if (from == buffer || from[-1] == '/')
438 if (!isalnum(*to)) to++;
441 if (!isalnum(from[-1])) from--;
443 /* This copy is ok, because we know that to is a substring of from. But
444 due to overlap we must use memmove() not Ustrcpy(). */
445 memmove(from, to, Ustrlen(to)+1);
449 /* If the file name is too long, it is an unrecoverable disaster */
452 die(US"exim: log file path too long: aborting",
453 US"Logging failure; please try later");
455 /* We now have the file name. Try to open an existing file. After a successful
456 open, arrange for automatic closure on exec(), and then return. */
462 O_APPEND|O_WRONLY, LOG_MODE);
467 (void)fcntl(*fd, F_SETFD, fcntl(*fd, F_GETFD) | FD_CLOEXEC);
472 /* Open was not successful: try creating the file. If this is a root process,
473 we must do the creating in a subprocess set to exim:exim in order to ensure
474 that the file is created with the right ownership. Otherwise, there can be a
475 race if another Exim process is trying to write to the log at the same time.
476 The use of SIGUSR1 by the exiwhat utility can provoke a lot of simultaneous
481 /* If we are already running as the Exim user (even if that user is root),
482 we can go ahead and create in the current process. */
484 if (euid == exim_uid) *fd = log_create(buffer);
486 /* Otherwise, if we are root, do the creation in an exim:exim subprocess. If we
487 are neither exim nor root, creation is not attempted. */
489 else if (euid == root_uid) *fd = log_create_as_exim(buffer);
491 /* If we now have an open file, set the close-on-exec flag and return. */
496 (void)fcntl(*fd, F_SETFD, fcntl(*fd, F_GETFD) | FD_CLOEXEC);
501 /* Creation failed. There are some circumstances in which we get here when
502 the effective uid is not root or exim, which is the problem. (For example, a
503 non-setuid binary with log_arguments set, called in certain ways.) Rather than
504 just bombing out, force the log to stderr and carry on if stderr is available.
507 if (euid != root_uid && euid != exim_uid && log_stderr)
509 *fd = fileno(log_stderr);
513 /* Otherwise this is a disaster. This call is deliberately ONLY to the panic
514 log. If possible, save a copy of the original line that was being logged. If we
515 are recursing (can't open the panic log either), the pointer will already be
516 set. Also, when we had to use a subprocess for the create we didn't retrieve
517 errno from it, so get the error from the open attempt above (which is often
518 meaningful enough, so leave it). */
520 if (!panic_save_buffer)
521 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
522 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
524 log_write(0, LOG_PANIC_DIE, "Cannot open %s log file \"%s\": %s: "
525 "euid=%d egid=%d", log_names[type], buffer, strerror(errno), euid, getegid());
533 if (type == lt_debug) unlink(CS debuglog_name);
538 /*************************************************
539 * Add configuration file info to log line *
540 *************************************************/
542 /* This is put in a function because it's needed twice (once for debugging,
546 ptr pointer to the end of the line we are building
549 Returns: updated pointer
553 log_config_info(gstring * g, int flags)
555 g = string_cat(g, US"Exim configuration error");
557 if (flags & (LOG_CONFIG_FOR & ~LOG_CONFIG))
558 return string_cat(g, US" for ");
560 if (flags & (LOG_CONFIG_IN & ~LOG_CONFIG))
561 g = string_fmt_append(g, " in line %d of %s", config_lineno, config_filename);
563 return string_catn(g, US":\n ", 4);
567 /*************************************************
568 * A write() operation failed *
569 *************************************************/
571 /* This function is called when write() fails on anything other than the panic
572 log, which can happen if a disk gets full or a file gets too large or whatever.
573 We try to save the relevant message in the panic_save buffer before crashing
576 The potential invoker should probably not call us for EINTR -1 writes. But
577 otherwise, short writes are bad as we don't do non-blocking writes to fds
578 subject to flow control. (If we do, that's new and the logic of this should
582 name the name of the log being written
583 length the string length being written
584 rc the return value from write()
586 Returns: does not return
590 log_write_failed(uschar *name, int length, int rc)
592 int save_errno = errno;
594 if (!panic_save_buffer)
595 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
596 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
598 log_write(0, LOG_PANIC_DIE, "failed to write to %s: length=%d result=%d "
599 "errno=%d (%s)", name, length, rc, save_errno,
600 (save_errno == 0)? "write incomplete" : strerror(save_errno));
606 /*************************************************
607 * Write to an fd, retrying after signals *
608 *************************************************/
610 /* Basic write to fd for logs, handling EINTR.
613 fd the fd to write to
614 buf the string to write
615 length the string length being written
618 length actually written, persisting an errno from write()
621 write_to_fd_buf(int fd, const uschar *buf, size_t length)
624 size_t total_written = 0;
625 const uschar *p = buf;
626 size_t left = length;
630 wrote = write(fd, p, left);
631 if (wrote == (ssize_t)-1)
633 if (errno == EINTR) continue;
636 total_written += wrote;
645 return total_written;
653 int sep = ':'; /* Fixed separator - outside use */
655 const uschar *tt = US LOG_FILE_PATH;
656 while ((t = string_nextinlist(&tt, &sep, log_buffer, LOG_BUFFER_SIZE)))
658 if (Ustrcmp(t, "syslog") == 0 || t[0] == 0) continue;
659 file_path = string_copy(t);
668 if (mainlogfd < 0) return;
669 (void)close(mainlogfd);
674 /*************************************************
675 * Write message to log file *
676 *************************************************/
678 /* Exim can be configured to log to local files, or use syslog, or both. This
679 is controlled by the setting of log_file_path. The following cases are
682 log_file_path = "" write files in the spool/log directory
683 log_file_path = "xxx" write files in the xxx directory
684 log_file_path = "syslog" write to syslog
685 log_file_path = "syslog : xxx" write to syslog and to files (any order)
687 The message always gets '\n' added on the end of it, since more than one
688 process may be writing to the log at once and we don't want intermingling to
689 happen in the middle of lines. To be absolutely sure of this we write the data
690 into a private buffer and then put it out in a single write() call.
692 The flags determine which log(s) the message is written to, or for syslogging,
693 which priority to use, and in the case of the panic log, whether the process
694 should die afterwards.
696 The variable really_exim is TRUE only when exim is running in privileged state
697 (i.e. not with a changed configuration or with testing options such as -brw).
698 If it is not, don't try to write to the log because permission will probably be
701 Avoid actually writing to the logs when exim is called with -bv or -bt to
702 test an address, but take other actions, such as panicking.
704 In Exim proper, the buffer for building the message is got at start-up, so that
705 nothing gets done if it can't be got. However, some functions that are also
706 used in utilities occasionally obey log_write calls in error situations, and it
707 is simplest to put a single malloc() here rather than put one in each utility.
708 Malloc is used directly because the store functions may call log_write().
710 If a message_id exists, we include it after the timestamp.
713 selector write to main log or LOG_INFO only if this value is zero, or if
714 its bit is set in log_selector[0]
715 flags each bit indicates some independent action:
716 LOG_SENDER add raw sender to the message
717 LOG_RECIPIENTS add raw recipients list to message
718 LOG_CONFIG add "Exim configuration error"
719 LOG_CONFIG_FOR add " for " instead of ":\n "
720 LOG_CONFIG_IN add " in line x[ of file y]"
721 LOG_MAIN write to main log or syslog LOG_INFO
722 LOG_REJECT write to reject log or syslog LOG_NOTICE
723 LOG_PANIC write to panic log or syslog LOG_ALERT
724 LOG_PANIC_DIE write to panic log or LOG_ALERT and then crash
725 format a printf() format
726 ... arguments for format
732 log_write(unsigned int selector, int flags, const char *format, ...)
736 gstring gs = { .size = LOG_BUFFER_SIZE-1, .ptr = 0, .s = log_buffer };
740 /* If panic_recurseflag is set, we have failed to open the panic log. This is
741 the ultimate disaster. First try to write the message to a debug file and/or
742 stderr and also to syslog. If panic_save_buffer is not NULL, it contains the
743 original log line that caused the problem. Afterwards, expire. */
745 if (panic_recurseflag)
747 uschar *extra = panic_save_buffer ? panic_save_buffer : US"";
748 if (debug_file) debug_printf("%s%s", extra, log_buffer);
749 if (log_stderr && log_stderr != debug_file)
750 fprintf(log_stderr, "%s%s", extra, log_buffer);
751 if (*extra) write_syslog(LOG_CRIT, extra);
752 write_syslog(LOG_CRIT, log_buffer);
753 die(US"exim: could not open panic log - aborting: see message(s) above",
754 US"Unexpected log failure, please try later");
757 /* Ensure we have a buffer (see comment above); this should never be obeyed
758 when running Exim proper, only when running utilities. */
761 if (!(log_buffer = US malloc(LOG_BUFFER_SIZE)))
763 fprintf(stderr, "exim: failed to get store for log buffer\n");
764 exim_exit(EXIT_FAILURE);
767 /* If we haven't already done so, inspect the setting of log_file_path to
768 determine whether to log to files and/or to syslog. Bits in logging_mode
769 control this, and for file logging, the path must end up in file_path. This
770 variable must be in permanent store because it may be required again later in
775 BOOL multiple = FALSE;
776 int old_pool = store_pool;
778 store_pool = POOL_PERM;
780 /* If nothing has been set, don't waste effort... the default values for the
781 statics are file_path="" and logging_mode = LOG_MODE_FILE. */
785 int sep = ':'; /* Fixed separator - outside use */
787 const uschar *ss = log_file_path;
790 while ((s = string_nextinlist(&ss, &sep, log_buffer, LOG_BUFFER_SIZE)))
792 if (Ustrcmp(s, "syslog") == 0)
793 logging_mode |= LOG_MODE_SYSLOG;
794 else if (logging_mode & LOG_MODE_FILE)
798 logging_mode |= LOG_MODE_FILE;
800 /* If a non-empty path is given, use it */
803 file_path = string_copy(s);
805 /* If the path is empty, we want to use the first non-empty, non-
806 syslog item in LOG_FILE_PATH, if there is one, since the value of
807 log_file_path may have been set at runtime. If there is no such item,
808 use the ultimate default in the spool directory. */
811 set_file_path(); /* Empty item in log_file_path */
812 } /* First non-syslog item in log_file_path */
813 } /* Scan of log_file_path */
816 /* If no modes have been selected, it is a major disaster */
818 if (logging_mode == 0)
819 die(US"Neither syslog nor file logging set in log_file_path",
820 US"Unexpected logging failure");
822 /* Set up the ultimate default if necessary. Then revert to the old store
823 pool, and record that we've sorted out the path. */
825 if (logging_mode & LOG_MODE_FILE && !file_path[0])
826 file_path = string_sprintf("%s/log/%%slog", spool_directory);
827 store_pool = old_pool;
828 path_inspected = TRUE;
830 /* If more than one file path was given, log a complaint. This recursive call
831 should work since we have now set up the routing. */
834 log_write(0, LOG_MAIN|LOG_PANIC,
835 "More than one path given in log_file_path: using %s", file_path);
838 /* If debugging, show all log entries, but don't show headers. Do it all
839 in one go so that it doesn't get split when multi-processing. */
845 g = string_catn(&gs, US"LOG:", 4);
847 /* Show the selector that was passed into the call. */
849 for (i = 0; i < log_options_count; i++)
851 unsigned int bitnum = log_options[i].bit;
852 if (bitnum < BITWORDSIZE && selector == BIT(bitnum))
853 g = string_fmt_append(g, " %s", log_options[i].name);
856 g = string_fmt_append(g, "%s%s%s%s\n ",
857 flags & LOG_MAIN ? " MAIN" : "",
858 flags & LOG_PANIC ? " PANIC" : "",
859 (flags & LOG_PANIC_DIE) == LOG_PANIC_DIE ? " DIE" : "",
860 flags & LOG_REJECT ? " REJECT" : "");
862 if (flags & LOG_CONFIG) g = log_config_info(g, flags);
864 /* We want to be able to log tainted info, but log_buffer is directly
865 malloc'd. So use deliberately taint-nonchecking routines to build into
866 it, trusting that we will never expand the results. */
868 va_start(ap, format);
870 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
873 g = string_cat(g, US"**** log string overflowed log buffer ****");
877 g->size = LOG_BUFFER_SIZE;
878 g = string_catn(g, US"\n", 1);
879 debug_printf("%s", string_from_gstring(g));
881 gs.size = LOG_BUFFER_SIZE-1; /* Having used the buffer for debug output, */
882 gs.ptr = 0; /* reset it for the real use. */
885 /* If no log file is specified, we are in a mess. */
887 if (!(flags & (LOG_MAIN|LOG_PANIC|LOG_REJECT)))
888 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "log_write called with no log "
891 /* There are some weird circumstances in which logging is disabled. */
893 if (f.disable_logging)
895 DEBUG(D_any) debug_printf("log writing disabled\n");
899 /* Handle disabled reject log */
901 if (!write_rejectlog) flags &= ~LOG_REJECT;
903 /* Create the main message in the log buffer. Do not include the message id
904 when called by a utility. */
906 g = string_fmt_append(&gs, "%s ", tod_stamp(tod_log));
910 if (!syslog_pid) pid_position[0] = g->ptr; /* remember begin … */
911 g = string_fmt_append(g, "[%d] ", (int)getpid());
912 if (!syslog_pid) pid_position[1] = g->ptr; /* … and end+1 of the PID */
915 if (f.really_exim && message_id[0] != 0)
916 g = string_fmt_append(g, "%s ", message_id);
918 if (flags & LOG_CONFIG)
919 g = log_config_info(g, flags);
921 va_start(ap, format);
925 /* We want to be able to log tainted info, but log_buffer is directly
926 malloc'd. So use deliberately taint-nonchecking routines to build into
927 it, trusting that we will never expand the results. */
929 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
932 g = string_cat(g, US"**** log string overflowed log buffer ****\n");
937 /* Add the raw, unrewritten, sender to the message if required. This is done
938 this way because it kind of fits with LOG_RECIPIENTS. */
940 if ( flags & LOG_SENDER
941 && g->ptr < LOG_BUFFER_SIZE - 10 - Ustrlen(raw_sender))
942 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " from <%s>", raw_sender);
944 /* Add list of recipients to the message if required; the raw list,
945 before rewriting, was saved in raw_recipients. There may be none, if an ACL
946 discarded them all. */
948 if ( flags & LOG_RECIPIENTS
949 && g->ptr < LOG_BUFFER_SIZE - 6
950 && raw_recipients_count > 0)
953 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " for", NULL);
954 for (i = 0; i < raw_recipients_count; i++)
956 uschar * s = raw_recipients[i];
957 if (LOG_BUFFER_SIZE - g->ptr < Ustrlen(s) + 3) break;
958 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " %s", s);
962 g = string_catn(g, US"\n", 1);
963 string_from_gstring(g);
965 /* Handle loggable errors when running a utility, or when address testing.
966 Write to log_stderr unless debugging (when it will already have been written),
967 or unless there is no log_stderr (expn called from daemon, for example). */
969 if (!f.really_exim || f.log_testing_mode)
973 && (selector == 0 || (selector & log_selector[0]) != 0)
976 fprintf(log_stderr, "LOG: %s", CS(log_buffer + 20)); /* no timestamp */
978 fprintf(log_stderr, "%s", CS log_buffer);
980 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
984 /* Handle the main log. We know that either syslog or file logging (or both) is
985 set up. A real file gets left open during reception or delivery once it has
986 been opened, but we don't want to keep on writing to it for too long after it
987 has been renamed. Therefore, do a stat() and see if the inode has changed, and
990 if ( flags & LOG_MAIN
991 && (!selector || selector & log_selector[0]))
993 if ( logging_mode & LOG_MODE_SYSLOG
994 && (syslog_duplication || !(flags & (LOG_REJECT|LOG_PANIC))))
995 write_syslog(LOG_INFO, log_buffer);
997 if (logging_mode & LOG_MODE_FILE)
1001 /* Check for a change to the mainlog file name when datestamping is in
1002 operation. This happens at midnight, at which point we want to roll over
1003 the file. Closing it has the desired effect. */
1005 if (mainlog_datestamp)
1007 uschar *nowstamp = tod_stamp(string_datestamp_type);
1008 if (Ustrncmp (mainlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1010 (void)close(mainlogfd); /* Close the file */
1011 mainlogfd = -1; /* Clear the file descriptor */
1012 mainlog_inode = 0; /* Unset the inode */
1013 mainlog_datestamp = NULL; /* Clear the datestamp */
1017 /* Otherwise, we want to check whether the file has been renamed by a
1018 cycling script. This could be "if else", but for safety's sake, leave it as
1019 "if" so that renaming the log starts a new file even when datestamping is
1023 if (Ustat(mainlog_name, &statbuf) < 0 || statbuf.st_ino != mainlog_inode)
1026 /* If the log is closed, open it. Then write the line. */
1030 open_log(&mainlogfd, lt_main, NULL); /* No return on error */
1031 if (fstat(mainlogfd, &statbuf) >= 0) mainlog_inode = statbuf.st_ino;
1034 /* Failing to write to the log is disastrous */
1036 written_len = write_to_fd_buf(mainlogfd, g->s, g->ptr);
1037 if (written_len != g->ptr)
1039 log_write_failed(US"main log", g->ptr, written_len);
1040 /* That function does not return */
1045 /* Handle the log for rejected messages. This can be globally disabled, in
1046 which case the flags are altered above. If there are any header lines (i.e. if
1047 the rejection is happening after the DATA phase), log the recipients and the
1050 if (flags & LOG_REJECT)
1052 if (header_list && LOGGING(rejected_header))
1057 if (recipients_count > 0)
1059 /* List the sender */
1061 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1062 "Envelope-from: <%s>\n", sender_address);
1065 /* List up to 5 recipients */
1067 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1068 "Envelope-to: <%s>\n", recipients_list[0].address);
1071 for (i = 1; i < recipients_count && i < 5; i++)
1073 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1074 " <%s>\n", recipients_list[i].address);
1078 if (i < recipients_count)
1080 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " ...\n", NULL);
1085 /* A header with a NULL text is an unfilled in Received: header */
1087 for (header_line * h = header_list; h; h = h->next) if (h->text)
1089 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1090 "%c %s", h->type, h->text);
1093 else /* Buffer is full; truncate */
1095 g->ptr -= 100; /* For message and separator */
1096 if (g->s[g->ptr-1] == '\n') g->ptr--;
1097 g = string_cat(g, US"\n*** truncated ***\n");
1103 /* Write to syslog or to a log file */
1105 if ( logging_mode & LOG_MODE_SYSLOG
1106 && (syslog_duplication || !(flags & LOG_PANIC)))
1107 write_syslog(LOG_NOTICE, string_from_gstring(g));
1109 /* Check for a change to the rejectlog file name when datestamping is in
1110 operation. This happens at midnight, at which point we want to roll over
1111 the file. Closing it has the desired effect. */
1113 if (logging_mode & LOG_MODE_FILE)
1115 struct stat statbuf;
1117 if (rejectlog_datestamp)
1119 uschar *nowstamp = tod_stamp(string_datestamp_type);
1120 if (Ustrncmp (rejectlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1122 (void)close(rejectlogfd); /* Close the file */
1123 rejectlogfd = -1; /* Clear the file descriptor */
1124 rejectlog_inode = 0; /* Unset the inode */
1125 rejectlog_datestamp = NULL; /* Clear the datestamp */
1129 /* Otherwise, we want to check whether the file has been renamed by a
1130 cycling script. This could be "if else", but for safety's sake, leave it as
1131 "if" so that renaming the log starts a new file even when datestamping is
1134 if (rejectlogfd >= 0)
1135 if (Ustat(rejectlog_name, &statbuf) < 0 ||
1136 statbuf.st_ino != rejectlog_inode)
1138 (void)close(rejectlogfd);
1140 rejectlog_inode = 0;
1143 /* Open the file if necessary, and write the data */
1145 if (rejectlogfd < 0)
1147 open_log(&rejectlogfd, lt_reject, NULL); /* No return on error */
1148 if (fstat(rejectlogfd, &statbuf) >= 0) rejectlog_inode = statbuf.st_ino;
1151 written_len = write_to_fd_buf(rejectlogfd, g->s, g->ptr);
1152 if (written_len != g->ptr)
1154 log_write_failed(US"reject log", g->ptr, written_len);
1155 /* That function does not return */
1161 /* Handle the panic log, which is not kept open like the others. If it fails to
1162 open, there will be a recursive call to log_write(). We detect this above and
1163 attempt to write to the system log as a last-ditch try at telling somebody. In
1164 all cases except mua_wrapper, try to write to log_stderr. */
1166 if (flags & LOG_PANIC)
1168 if (log_stderr && log_stderr != debug_file && !mua_wrapper)
1169 fprintf(log_stderr, "%s", CS string_from_gstring(g));
1171 if (logging_mode & LOG_MODE_SYSLOG)
1172 write_syslog(LOG_ALERT, log_buffer);
1174 /* If this panic logging was caused by a failure to open the main log,
1175 the original log line is in panic_save_buffer. Make an attempt to write it. */
1177 if (logging_mode & LOG_MODE_FILE)
1179 panic_recurseflag = TRUE;
1180 open_log(&paniclogfd, lt_panic, NULL); /* Won't return on failure */
1181 panic_recurseflag = FALSE;
1183 if (panic_save_buffer)
1185 int i = write(paniclogfd, panic_save_buffer, Ustrlen(panic_save_buffer));
1186 i = i; /* compiler quietening */
1189 written_len = write_to_fd_buf(paniclogfd, g->s, g->ptr);
1190 if (written_len != g->ptr)
1192 int save_errno = errno;
1193 write_syslog(LOG_CRIT, log_buffer);
1194 sprintf(CS log_buffer, "write failed on panic log: length=%d result=%d "
1195 "errno=%d (%s)", g->ptr, (int)written_len, save_errno, strerror(save_errno));
1196 write_syslog(LOG_CRIT, string_from_gstring(g));
1197 flags |= LOG_PANIC_DIE;
1200 (void)close(paniclogfd);
1203 /* Give up if the DIE flag is set */
1205 if ((flags & LOG_PANIC_DIE) != LOG_PANIC)
1206 die(NULL, US"Unexpected failure, please try later");
1212 /*************************************************
1213 * Close any open log files *
1214 *************************************************/
1220 { (void)close(mainlogfd); mainlogfd = -1; }
1221 if (rejectlogfd >= 0)
1222 { (void)close(rejectlogfd); rejectlogfd = -1; }
1224 syslog_open = FALSE;
1229 /*************************************************
1230 * Multi-bit set or clear *
1231 *************************************************/
1233 /* These functions take a list of bit indexes (terminated by -1) and
1234 clear or set the corresponding bits in the selector.
1237 selector address of the bit string
1238 selsize number of words in the bit string
1239 bits list of bits to set
1243 bits_clear(unsigned int *selector, size_t selsize, int *bits)
1245 for(; *bits != -1; ++bits)
1246 BIT_CLEAR(selector, selsize, *bits);
1250 bits_set(unsigned int *selector, size_t selsize, int *bits)
1252 for(; *bits != -1; ++bits)
1253 BIT_SET(selector, selsize, *bits);
1258 /*************************************************
1259 * Decode bit settings for log/debug *
1260 *************************************************/
1262 /* This function decodes a string containing bit settings in the form of +name
1263 and/or -name sequences, and sets/unsets bits in a bit string accordingly. It
1264 also recognizes a numeric setting of the form =<number>, but this is not
1265 intended for user use. It's an easy way for Exim to pass the debug settings
1266 when it is re-exec'ed.
1268 The option table is a list of names and bit indexes. The index -1
1269 means "set all bits, except for those listed in notall". The notall
1270 list is terminated by -1.
1272 The action taken for bad values varies depending upon why we're here.
1273 For log messages, or if the debugging is triggered from config, then we write
1274 to the log on the way out. For debug setting triggered from the command-line,
1275 we treat it as an unknown option: error message to stderr and die.
1278 selector address of the bit string
1279 selsize number of words in the bit string
1280 notall list of bits to exclude from "all"
1281 string the configured string
1282 options the table of option names
1284 which "log" or "debug"
1285 flags DEBUG_FROM_CONFIG
1287 Returns: nothing on success - bomb out on failure
1291 decode_bits(unsigned int *selector, size_t selsize, int *notall,
1292 uschar *string, bit_table *options, int count, uschar *which, int flags)
1295 if (!string) return;
1299 char *end; /* Not uschar */
1300 memset(selector, 0, sizeof(*selector)*selsize);
1301 *selector = strtoul(CS string+1, &end, 0);
1303 errmsg = string_sprintf("malformed numeric %s_selector setting: %s", which,
1308 /* Handle symbolic setting */
1315 bit_table *start, *end;
1317 Uskip_whitespace(&string);
1318 if (!*string) return;
1320 if (*string != '+' && *string != '-')
1322 errmsg = string_sprintf("malformed %s_selector setting: "
1323 "+ or - expected but found \"%s\"", which, string);
1327 adding = *string++ == '+';
1329 while (isalnum(*string) || *string == '_') string++;
1333 end = options + count;
1337 bit_table *middle = start + (end - start)/2;
1338 int c = Ustrncmp(s, middle->name, len);
1340 if (middle->name[len] != 0) c = -1; else
1342 unsigned int bit = middle->bit;
1348 memset(selector, -1, sizeof(*selector)*selsize);
1349 bits_clear(selector, selsize, notall);
1352 memset(selector, 0, sizeof(*selector)*selsize);
1355 BIT_SET(selector, selsize, bit);
1357 BIT_CLEAR(selector, selsize, bit);
1359 break; /* Out of loop to match selector name */
1361 if (c < 0) end = middle; else start = middle + 1;
1362 } /* Loop to match selector name */
1366 errmsg = string_sprintf("unknown %s_selector setting: %c%.*s", which,
1367 adding? '+' : '-', len, s);
1370 } /* Loop for selector names */
1372 /* Handle disasters */
1375 if (Ustrcmp(which, "debug") == 0)
1377 if (flags & DEBUG_FROM_CONFIG)
1379 log_write(0, LOG_CONFIG|LOG_PANIC, "%s", errmsg);
1382 fprintf(stderr, "exim: %s\n", errmsg);
1385 else log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "%s", errmsg);
1390 /*************************************************
1391 * Activate a debug logfile (late) *
1392 *************************************************/
1394 /* Normally, debugging is activated from the command-line; it may be useful
1395 within the configuration to activate debugging later, based on certain
1396 conditions. If debugging is already in progress, we return early, no action
1397 taken (besides debug-logging that we wanted debug-logging).
1399 Failures in options are not fatal but will result in paniclog entries for the
1402 The first use of this is in ACL logic, "control = debug/tag=foo/opts=+expand"
1403 which can be combined with conditions, etc, to activate extra logging only
1404 for certain sources. The second use is inetd wait mode debug preservation. */
1407 debug_logging_activate(uschar *tag_name, uschar *opts)
1413 debug_printf("DEBUGGING ACTIVATED FROM WITHIN CONFIG.\n"
1414 "DEBUG: Tag=\"%s\" opts=\"%s\"\n", tag_name, opts ? opts : US"");
1418 if (tag_name != NULL && (Ustrchr(tag_name, '/') != NULL))
1420 log_write(0, LOG_MAIN|LOG_PANIC, "debug tag may not contain a '/' in: %s",
1425 debug_selector = D_default;
1427 decode_bits(&debug_selector, 1, debug_notall, opts,
1428 debug_options, debug_options_count, US"debug", DEBUG_FROM_CONFIG);
1430 /* When activating from a transport process we may never have logged at all
1431 resulting in certain setup not having been done. Hack this for now so we
1432 do not segfault; note that nondefault log locations will not work */
1434 if (!*file_path) set_file_path();
1436 open_log(&fd, lt_debug, tag_name);
1439 debug_file = fdopen(fd, "w");
1441 log_write(0, LOG_MAIN|LOG_PANIC, "unable to open debug log");
1446 debug_logging_stop(void)
1448 if (!debug_file || !debuglog_name[0]) return;
1453 unlink_log(lt_debug);