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_open_already_exim(uschar * const name)
272 const int flags = O_WRONLY | O_APPEND | O_CREAT | O_NONBLOCK;
274 if (geteuid() != exim_uid)
280 fd = Uopen(name, flags, LOG_MODE);
282 /* If creation failed, attempt to build a log directory in case that is the
285 if (fd < 0 && errno == ENOENT)
288 uschar *lastslash = Ustrrchr(name, '/');
290 created = directory_make(NULL, name, LOG_DIRECTORY_MODE, FALSE);
293 debug_printf("created log directory %s\n", name);
295 debug_printf("failed to create log directory %s: %s\n", name, strerror(errno));
297 if (created) fd = Uopen(name, flags, LOG_MODE);
305 /* Inspired by OpenSSH's mm_send_fd(). Thanks!
306 Send fd over socketpair.
307 Return: true iff good.
311 log_send_fd(const int sock, const int fd)
316 char buf[CMSG_SPACE(sizeof(int))];
318 struct cmsghdr *cmsg;
320 struct iovec vec = {.iov_base = &ch, .iov_len = 1};
323 memset(&msg, 0, sizeof(msg));
324 memset(&cmsgbuf, 0, sizeof(cmsgbuf));
325 msg.msg_control = &cmsgbuf.buf;
326 msg.msg_controllen = sizeof(cmsgbuf.buf);
328 cmsg = CMSG_FIRSTHDR(&msg);
329 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
330 cmsg->cmsg_level = SOL_SOCKET;
331 cmsg->cmsg_type = SCM_RIGHTS;
332 *(int *)CMSG_DATA(cmsg) = fd;
337 while ((n = sendmsg(sock, &msg, 0)) == -1 && errno == EINTR);
341 /* Inspired by OpenSSH's mm_receive_fd(). Thanks!
342 Return fd passed over socketpair, or -1 on error.
346 log_recv_fd(const int sock)
351 char buf[CMSG_SPACE(sizeof(int))];
353 struct cmsghdr *cmsg;
355 struct iovec vec = {.iov_base = &ch, .iov_len = 1};
359 memset(&msg, 0, sizeof(msg));
363 memset(&cmsgbuf, 0, sizeof(cmsgbuf));
364 msg.msg_control = &cmsgbuf.buf;
365 msg.msg_controllen = sizeof(cmsgbuf.buf);
367 while ((n = recvmsg(sock, &msg, 0)) == -1 && errno == EINTR) ;
368 if (n != 1 || ch != 'A') return -1;
370 if (!(cmsg = CMSG_FIRSTHDR(&msg))) return -1;
371 if (cmsg->cmsg_type != SCM_RIGHTS) return -1;
372 if ((fd = *(const int *)CMSG_DATA(cmsg)) < 0) return -1;
378 /*************************************************
379 * Create a log file as the exim user *
380 *************************************************/
382 /* This function is called when we are root to spawn an exim:exim subprocess
383 in which we can create a log file. It must be signal-safe since it is called
384 by the usr1_handler().
389 Returns: a file descriptor, or < 0 on failure (errno set)
393 log_open_as_exim(uschar * const name)
396 const uid_t euid = geteuid();
398 if (euid == exim_uid)
399 fd = log_open_already_exim(name);
400 else if (euid == root_uid)
403 if (socketpair(AF_UNIX, SOCK_STREAM, 0, sock) == 0)
405 const pid_t pid = fork();
408 (void)close(sock[0]);
409 if ( setgroups(1, &exim_gid) != 0
410 || setgid(exim_gid) != 0
411 || setuid(exim_uid) != 0
413 || getuid() != exim_uid || geteuid() != exim_uid
414 || getgid() != exim_gid || getegid() != exim_gid
416 || (fd = log_open_already_exim(name)) < 0
417 || !log_send_fd(sock[1], fd)
418 ) _exit(EXIT_FAILURE);
419 (void)close(sock[1]);
423 (void)close(sock[1]);
426 fd = log_recv_fd(sock[0]);
427 while (waitpid(pid, NULL, 0) == -1 && errno == EINTR);
429 (void)close(sock[0]);
436 flags = fcntl(fd, F_GETFD);
437 if (flags != -1) (void)fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
438 flags = fcntl(fd, F_GETFL);
439 if (flags != -1) (void)fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
450 /*************************************************
452 *************************************************/
454 /* This function opens one of a number of logs, creating the log directory if
455 it does not exist. This may be called recursively on failure, in order to open
458 The directory is in the static variable file_path. This is static so that
459 the work of sorting out the path is done just once per Exim process.
461 Exim is normally configured to avoid running as root wherever possible, the log
462 files must be owned by the non-privileged exim user. To ensure this, first try
463 an open without O_CREAT - most of the time this will succeed. If it fails, try
464 to create the file; if running as root, this must be done in a subprocess to
468 fd where to return the resulting file descriptor
469 type lt_main, lt_reject, lt_panic, or lt_debug
470 tag optional tag to include in the name (only hooked up for debug)
476 open_log(int *fd, int type, uschar *tag)
480 uschar buffer[LOG_NAME_SIZE];
482 /* The names of the log files are controlled by file_path. The panic log is
483 written to the same directory as the main and reject logs, but its name does
484 not have a datestamp. The use of datestamps is indicated by %D/%M in file_path.
485 When opening the panic log, if %D or %M is present, we remove the datestamp
486 from the generated name; if it is at the start, remove a following
487 non-alphanumeric character as well; otherwise, remove a preceding
488 non-alphanumeric character. This is definitely kludgy, but it sort of does what
489 people want, I hope. */
491 ok = string_format(buffer, sizeof(buffer), CS file_path, log_names[type]);
496 /* Save the name of the mainlog for rollover processing. Without a datestamp,
497 it gets statted to see if it has been cycled. With a datestamp, the datestamp
498 will be compared. The static slot for saving it is the same size as buffer,
499 and the text has been checked above to fit, so this use of strcpy() is OK. */
501 Ustrcpy(mainlog_name, buffer);
502 if (string_datestamp_offset > 0)
503 mainlog_datestamp = mainlog_name + string_datestamp_offset;
507 /* Ditto for the reject log */
509 Ustrcpy(rejectlog_name, buffer);
510 if (string_datestamp_offset > 0)
511 rejectlog_datestamp = rejectlog_name + string_datestamp_offset;
515 /* and deal with the debug log (which keeps the datestamp, but does not
518 Ustrcpy(debuglog_name, buffer);
521 /* this won't change the offset of the datestamp */
522 ok2 = string_format(buffer, sizeof(buffer), "%s%s",
525 Ustrcpy(debuglog_name, buffer);
530 /* Remove any datestamp if this is the panic log. This is rare, so there's no
531 need to optimize getting the datestamp length. We remove one non-alphanumeric
532 char afterwards if at the start, otherwise one before. */
534 if (string_datestamp_offset >= 0)
536 uschar * from = buffer + string_datestamp_offset;
537 uschar * to = from + string_datestamp_length;
539 if (from == buffer || from[-1] == '/')
541 if (!isalnum(*to)) to++;
544 if (!isalnum(from[-1])) from--;
546 /* This copy is ok, because we know that to is a substring of from. But
547 due to overlap we must use memmove() not Ustrcpy(). */
548 memmove(from, to, Ustrlen(to)+1);
553 /* If the file name is too long, it is an unrecoverable disaster */
556 die(US"exim: log file path too long: aborting",
557 US"Logging failure; please try later");
559 /* We now have the file name. After a successful open, return. */
561 *fd = log_open_as_exim(buffer);
568 /* Creation failed. There are some circumstances in which we get here when
569 the effective uid is not root or exim, which is the problem. (For example, a
570 non-setuid binary with log_arguments set, called in certain ways.) Rather than
571 just bombing out, force the log to stderr and carry on if stderr is available.
574 if (euid != root_uid && euid != exim_uid && log_stderr)
576 *fd = fileno(log_stderr);
580 /* Otherwise this is a disaster. This call is deliberately ONLY to the panic
581 log. If possible, save a copy of the original line that was being logged. If we
582 are recursing (can't open the panic log either), the pointer will already be
583 set. Also, when we had to use a subprocess for the create we didn't retrieve
584 errno from it, so get the error from the open attempt above (which is often
585 meaningful enough, so leave it). */
587 if (!panic_save_buffer)
588 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
589 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
591 log_write(0, LOG_PANIC_DIE, "Cannot open %s log file \"%s\": %s: "
592 "euid=%d egid=%d", log_names[type], buffer, strerror(errno), euid, getegid());
600 if (type == lt_debug) unlink(CS debuglog_name);
605 /*************************************************
606 * Add configuration file info to log line *
607 *************************************************/
609 /* This is put in a function because it's needed twice (once for debugging,
613 ptr pointer to the end of the line we are building
616 Returns: updated pointer
620 log_config_info(gstring * g, int flags)
622 g = string_cat(g, US"Exim configuration error");
624 if (flags & (LOG_CONFIG_FOR & ~LOG_CONFIG))
625 return string_cat(g, US" for ");
627 if (flags & (LOG_CONFIG_IN & ~LOG_CONFIG))
628 g = string_fmt_append(g, " in line %d of %s", config_lineno, config_filename);
630 return string_catn(g, US":\n ", 4);
634 /*************************************************
635 * A write() operation failed *
636 *************************************************/
638 /* This function is called when write() fails on anything other than the panic
639 log, which can happen if a disk gets full or a file gets too large or whatever.
640 We try to save the relevant message in the panic_save buffer before crashing
643 The potential invoker should probably not call us for EINTR -1 writes. But
644 otherwise, short writes are bad as we don't do non-blocking writes to fds
645 subject to flow control. (If we do, that's new and the logic of this should
649 name the name of the log being written
650 length the string length being written
651 rc the return value from write()
653 Returns: does not return
657 log_write_failed(uschar *name, int length, int rc)
659 int save_errno = errno;
661 if (!panic_save_buffer)
662 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
663 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
665 log_write(0, LOG_PANIC_DIE, "failed to write to %s: length=%d result=%d "
666 "errno=%d (%s)", name, length, rc, save_errno,
667 (save_errno == 0)? "write incomplete" : strerror(save_errno));
673 /*************************************************
674 * Write to an fd, retrying after signals *
675 *************************************************/
677 /* Basic write to fd for logs, handling EINTR.
680 fd the fd to write to
681 buf the string to write
682 length the string length being written
685 length actually written, persisting an errno from write()
688 write_to_fd_buf(int fd, const uschar *buf, size_t length)
691 size_t total_written = 0;
692 const uschar *p = buf;
693 size_t left = length;
697 wrote = write(fd, p, left);
698 if (wrote == (ssize_t)-1)
700 if (errno == EINTR) continue;
703 total_written += wrote;
712 return total_written;
716 /* Pull the file out of the configured or the compiled-in list.
717 Called for an empty log_file_path element, for debug logging activation
718 when file_path has not previously been set, and from the appenfile transport setup. */
721 set_file_path(BOOL *multiple)
724 int sep = ':'; /* Fixed separator - outside use */
725 const uschar *ss = *log_file_path ? log_file_path : US LOG_FILE_PATH;
728 for (logging_mode = 0;
729 s = string_nextinlist(&ss, &sep, log_buffer, LOG_BUFFER_SIZE); )
731 if (Ustrcmp(s, "syslog") == 0)
732 logging_mode |= LOG_MODE_SYSLOG;
733 else if (!(logging_mode & LOG_MODE_FILE)) /* no file yet */
735 logging_mode |= LOG_MODE_FILE;
736 if (*s) file_path = string_copy(s); /* If a non-empty path is given, use it */
738 else if (multiple) *multiple = TRUE;
741 logging_mode = LOG_MODE_FILE;
743 /* Set up the ultimate default if necessary. */
745 if (logging_mode & LOG_MODE_FILE && !*file_path)
746 if (LOG_FILE_PATH[0])
748 /* If we still do not have a file_path, we take
749 the first non-empty, non-syslog item in LOG_FILE_PATH, if there is
750 one. If there is no such item, use the ultimate default in the
753 for (ss = US LOG_FILE_PATH;
754 s = string_nextinlist(&ss, &sep, log_buffer, LOG_BUFFER_SIZE);)
756 if (*s != '/') continue;
757 file_path = string_copy(s);
760 else file_path = string_sprintf("%s/log/%%slog", spool_directory);
767 /* avoid closing it if it is closed already or if we do not see a chance
768 to open the file mainlog later again */
769 if (mainlogfd < 0 /* already closed */
770 || !(geteuid() == 0 || geteuid() == exim_uid))
772 (void)close(mainlogfd);
777 /*************************************************
778 * Write message to log file *
779 *************************************************/
781 /* Exim can be configured to log to local files, or use syslog, or both. This
782 is controlled by the setting of log_file_path. The following cases are
785 log_file_path = "" write files in the spool/log directory
786 log_file_path = "xxx" write files in the xxx directory
787 log_file_path = "syslog" write to syslog
788 log_file_path = "syslog : xxx" write to syslog and to files (any order)
790 The message always gets '\n' added on the end of it, since more than one
791 process may be writing to the log at once and we don't want intermingling to
792 happen in the middle of lines. To be absolutely sure of this we write the data
793 into a private buffer and then put it out in a single write() call.
795 The flags determine which log(s) the message is written to, or for syslogging,
796 which priority to use, and in the case of the panic log, whether the process
797 should die afterwards.
799 The variable really_exim is TRUE only when exim is running in privileged state
800 (i.e. not with a changed configuration or with testing options such as -brw).
801 If it is not, don't try to write to the log because permission will probably be
804 Avoid actually writing to the logs when exim is called with -bv or -bt to
805 test an address, but take other actions, such as panicking.
807 In Exim proper, the buffer for building the message is got at start-up, so that
808 nothing gets done if it can't be got. However, some functions that are also
809 used in utilities occasionally obey log_write calls in error situations, and it
810 is simplest to put a single malloc() here rather than put one in each utility.
811 Malloc is used directly because the store functions may call log_write().
813 If a message_id exists, we include it after the timestamp.
816 selector write to main log or LOG_INFO only if this value is zero, or if
817 its bit is set in log_selector[0]
818 flags each bit indicates some independent action:
819 LOG_SENDER add raw sender to the message
820 LOG_RECIPIENTS add raw recipients list to message
821 LOG_CONFIG add "Exim configuration error"
822 LOG_CONFIG_FOR add " for " instead of ":\n "
823 LOG_CONFIG_IN add " in line x[ of file y]"
824 LOG_MAIN write to main log or syslog LOG_INFO
825 LOG_REJECT write to reject log or syslog LOG_NOTICE
826 LOG_PANIC write to panic log or syslog LOG_ALERT
827 LOG_PANIC_DIE write to panic log or LOG_ALERT and then crash
828 format a printf() format
829 ... arguments for format
835 log_write(unsigned int selector, int flags, const char *format, ...)
839 gstring gs = { .size = LOG_BUFFER_SIZE-1, .ptr = 0, .s = log_buffer };
843 /* If panic_recurseflag is set, we have failed to open the panic log. This is
844 the ultimate disaster. First try to write the message to a debug file and/or
845 stderr and also to syslog. If panic_save_buffer is not NULL, it contains the
846 original log line that caused the problem. Afterwards, expire. */
848 if (panic_recurseflag)
850 uschar *extra = panic_save_buffer ? panic_save_buffer : US"";
851 if (debug_file) debug_printf("%s%s", extra, log_buffer);
852 if (log_stderr && log_stderr != debug_file)
853 fprintf(log_stderr, "%s%s", extra, log_buffer);
854 if (*extra) write_syslog(LOG_CRIT, extra);
855 write_syslog(LOG_CRIT, log_buffer);
856 die(US"exim: could not open panic log - aborting: see message(s) above",
857 US"Unexpected log failure, please try later");
860 /* Ensure we have a buffer (see comment above); this should never be obeyed
861 when running Exim proper, only when running utilities. */
864 if (!(log_buffer = US malloc(LOG_BUFFER_SIZE)))
866 fprintf(stderr, "exim: failed to get store for log buffer\n");
867 exim_exit(EXIT_FAILURE);
870 /* If we haven't already done so, inspect the setting of log_file_path to
871 determine whether to log to files and/or to syslog. Bits in logging_mode
872 control this, and for file logging, the path must end up in file_path. This
873 variable must be in permanent store because it may be required again later in
878 BOOL multiple = FALSE;
879 int old_pool = store_pool;
881 store_pool = POOL_PERM;
883 /* make sure that we have a valid log file path in "file_path",
884 the open_log() later relies on it */
885 set_file_path(&multiple);
887 /* If no modes have been selected, it is a major disaster */
889 if (logging_mode == 0)
890 die(US"Neither syslog nor file logging set in log_file_path",
891 US"Unexpected logging failure");
893 /* Revert to the old store pool, and record that we've sorted out the path. */
895 store_pool = old_pool;
896 path_inspected = TRUE;
898 /* If more than one file path was given, log a complaint. This recursive call
899 should work since we have now set up the routing. */
902 log_write(0, LOG_MAIN|LOG_PANIC,
903 "More than one path given in log_file_path: using %s", file_path);
906 /* If debugging, show all log entries, but don't show headers. Do it all
907 in one go so that it doesn't get split when multi-processing. */
913 g = string_catn(&gs, US"LOG:", 4);
915 /* Show the selector that was passed into the call. */
917 for (i = 0; i < log_options_count; i++)
919 unsigned int bitnum = log_options[i].bit;
920 if (bitnum < BITWORDSIZE && selector == BIT(bitnum))
921 g = string_fmt_append(g, " %s", log_options[i].name);
924 g = string_fmt_append(g, "%s%s%s%s\n ",
925 flags & LOG_MAIN ? " MAIN" : "",
926 flags & LOG_PANIC ? " PANIC" : "",
927 (flags & LOG_PANIC_DIE) == LOG_PANIC_DIE ? " DIE" : "",
928 flags & LOG_REJECT ? " REJECT" : "");
930 if (flags & LOG_CONFIG) g = log_config_info(g, flags);
932 /* We want to be able to log tainted info, but log_buffer is directly
933 malloc'd. So use deliberately taint-nonchecking routines to build into
934 it, trusting that we will never expand the results. */
936 va_start(ap, format);
938 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
941 g = string_cat(g, US"**** log string overflowed log buffer ****");
945 g->size = LOG_BUFFER_SIZE;
946 g = string_catn(g, US"\n", 1);
947 debug_printf("%s", string_from_gstring(g));
949 gs.size = LOG_BUFFER_SIZE-1; /* Having used the buffer for debug output, */
950 gs.ptr = 0; /* reset it for the real use. */
953 /* If no log file is specified, we are in a mess. */
955 if (!(flags & (LOG_MAIN|LOG_PANIC|LOG_REJECT)))
956 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "log_write called with no log "
959 /* There are some weird circumstances in which logging is disabled. */
961 if (f.disable_logging)
963 DEBUG(D_any) debug_printf("log writing disabled\n");
964 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
968 /* Handle disabled reject log */
970 if (!write_rejectlog) flags &= ~LOG_REJECT;
972 /* Create the main message in the log buffer. Do not include the message id
973 when called by a utility. */
975 g = string_fmt_append(&gs, "%s ", tod_stamp(tod_log));
979 if (!syslog_pid) pid_position[0] = g->ptr; /* remember begin … */
980 g = string_fmt_append(g, "[%d] ", (int)getpid());
981 if (!syslog_pid) pid_position[1] = g->ptr; /* … and end+1 of the PID */
984 if (f.really_exim && message_id[0] != 0)
985 g = string_fmt_append(g, "%s ", message_id);
987 if (flags & LOG_CONFIG)
988 g = log_config_info(g, flags);
990 va_start(ap, format);
994 /* We want to be able to log tainted info, but log_buffer is directly
995 malloc'd. So use deliberately taint-nonchecking routines to build into
996 it, trusting that we will never expand the results. */
998 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
1001 g = string_cat(g, US"**** log string overflowed log buffer ****\n");
1006 /* Add the raw, unrewritten, sender to the message if required. This is done
1007 this way because it kind of fits with LOG_RECIPIENTS. */
1009 if ( flags & LOG_SENDER
1010 && g->ptr < LOG_BUFFER_SIZE - 10 - Ustrlen(raw_sender))
1011 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " from <%s>", raw_sender);
1013 /* Add list of recipients to the message if required; the raw list,
1014 before rewriting, was saved in raw_recipients. There may be none, if an ACL
1015 discarded them all. */
1017 if ( flags & LOG_RECIPIENTS
1018 && g->ptr < LOG_BUFFER_SIZE - 6
1019 && raw_recipients_count > 0)
1022 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " for", NULL);
1023 for (i = 0; i < raw_recipients_count; i++)
1025 uschar * s = raw_recipients[i];
1026 if (LOG_BUFFER_SIZE - g->ptr < Ustrlen(s) + 3) break;
1027 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " %s", s);
1031 g = string_catn(g, US"\n", 1);
1032 string_from_gstring(g);
1034 /* Handle loggable errors when running a utility, or when address testing.
1035 Write to log_stderr unless debugging (when it will already have been written),
1036 or unless there is no log_stderr (expn called from daemon, for example). */
1038 if (!f.really_exim || f.log_testing_mode)
1040 if ( !debug_selector
1042 && (selector == 0 || (selector & log_selector[0]) != 0)
1045 fprintf(log_stderr, "LOG: %s", CS(log_buffer + 20)); /* no timestamp */
1047 fprintf(log_stderr, "%s", CS log_buffer);
1049 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
1053 /* Handle the main log. We know that either syslog or file logging (or both) is
1054 set up. A real file gets left open during reception or delivery once it has
1055 been opened, but we don't want to keep on writing to it for too long after it
1056 has been renamed. Therefore, do a stat() and see if the inode has changed, and
1059 if ( flags & LOG_MAIN
1060 && (!selector || selector & log_selector[0]))
1062 if ( logging_mode & LOG_MODE_SYSLOG
1063 && (syslog_duplication || !(flags & (LOG_REJECT|LOG_PANIC))))
1064 write_syslog(LOG_INFO, log_buffer);
1066 if (logging_mode & LOG_MODE_FILE)
1068 struct stat statbuf;
1070 /* Check for a change to the mainlog file name when datestamping is in
1071 operation. This happens at midnight, at which point we want to roll over
1072 the file. Closing it has the desired effect. */
1074 if (mainlog_datestamp)
1076 uschar *nowstamp = tod_stamp(string_datestamp_type);
1077 if (Ustrncmp (mainlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1079 (void)close(mainlogfd); /* Close the file */
1080 mainlogfd = -1; /* Clear the file descriptor */
1081 mainlog_inode = 0; /* Unset the inode */
1082 mainlog_datestamp = NULL; /* Clear the datestamp */
1086 /* Otherwise, we want to check whether the file has been renamed by a
1087 cycling script. This could be "if else", but for safety's sake, leave it as
1088 "if" so that renaming the log starts a new file even when datestamping is
1092 if (Ustat(mainlog_name, &statbuf) < 0 || statbuf.st_ino != mainlog_inode)
1095 /* If the log is closed, open it. Then write the line. */
1099 open_log(&mainlogfd, lt_main, NULL); /* No return on error */
1100 if (fstat(mainlogfd, &statbuf) >= 0) mainlog_inode = statbuf.st_ino;
1103 /* Failing to write to the log is disastrous */
1105 written_len = write_to_fd_buf(mainlogfd, g->s, g->ptr);
1106 if (written_len != g->ptr)
1108 log_write_failed(US"main log", g->ptr, written_len);
1109 /* That function does not return */
1114 /* Handle the log for rejected messages. This can be globally disabled, in
1115 which case the flags are altered above. If there are any header lines (i.e. if
1116 the rejection is happening after the DATA phase), log the recipients and the
1119 if (flags & LOG_REJECT)
1121 if (header_list && LOGGING(rejected_header))
1126 if (recipients_count > 0)
1128 /* List the sender */
1130 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1131 "Envelope-from: <%s>\n", sender_address);
1134 /* List up to 5 recipients */
1136 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1137 "Envelope-to: <%s>\n", recipients_list[0].address);
1140 for (i = 1; i < recipients_count && i < 5; i++)
1142 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1143 " <%s>\n", recipients_list[i].address);
1147 if (i < recipients_count)
1149 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " ...\n", NULL);
1154 /* A header with a NULL text is an unfilled in Received: header */
1156 for (header_line * h = header_list; h; h = h->next) if (h->text)
1158 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1159 "%c %s", h->type, h->text);
1162 else /* Buffer is full; truncate */
1164 g->ptr -= 100; /* For message and separator */
1165 if (g->s[g->ptr-1] == '\n') g->ptr--;
1166 g = string_cat(g, US"\n*** truncated ***\n");
1172 /* Write to syslog or to a log file */
1174 if ( logging_mode & LOG_MODE_SYSLOG
1175 && (syslog_duplication || !(flags & LOG_PANIC)))
1176 write_syslog(LOG_NOTICE, string_from_gstring(g));
1178 /* Check for a change to the rejectlog file name when datestamping is in
1179 operation. This happens at midnight, at which point we want to roll over
1180 the file. Closing it has the desired effect. */
1182 if (logging_mode & LOG_MODE_FILE)
1184 struct stat statbuf;
1186 if (rejectlog_datestamp)
1188 uschar *nowstamp = tod_stamp(string_datestamp_type);
1189 if (Ustrncmp (rejectlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1191 (void)close(rejectlogfd); /* Close the file */
1192 rejectlogfd = -1; /* Clear the file descriptor */
1193 rejectlog_inode = 0; /* Unset the inode */
1194 rejectlog_datestamp = NULL; /* Clear the datestamp */
1198 /* Otherwise, we want to check whether the file has been renamed by a
1199 cycling script. This could be "if else", but for safety's sake, leave it as
1200 "if" so that renaming the log starts a new file even when datestamping is
1203 if (rejectlogfd >= 0)
1204 if (Ustat(rejectlog_name, &statbuf) < 0 ||
1205 statbuf.st_ino != rejectlog_inode)
1207 (void)close(rejectlogfd);
1209 rejectlog_inode = 0;
1212 /* Open the file if necessary, and write the data */
1214 if (rejectlogfd < 0)
1216 open_log(&rejectlogfd, lt_reject, NULL); /* No return on error */
1217 if (fstat(rejectlogfd, &statbuf) >= 0) rejectlog_inode = statbuf.st_ino;
1220 written_len = write_to_fd_buf(rejectlogfd, g->s, g->ptr);
1221 if (written_len != g->ptr)
1223 log_write_failed(US"reject log", g->ptr, written_len);
1224 /* That function does not return */
1230 /* Handle the panic log, which is not kept open like the others. If it fails to
1231 open, there will be a recursive call to log_write(). We detect this above and
1232 attempt to write to the system log as a last-ditch try at telling somebody. In
1233 all cases except mua_wrapper, try to write to log_stderr. */
1235 if (flags & LOG_PANIC)
1237 if (log_stderr && log_stderr != debug_file && !mua_wrapper)
1238 fprintf(log_stderr, "%s", CS string_from_gstring(g));
1240 if (logging_mode & LOG_MODE_SYSLOG)
1241 write_syslog(LOG_ALERT, log_buffer);
1243 /* If this panic logging was caused by a failure to open the main log,
1244 the original log line is in panic_save_buffer. Make an attempt to write it. */
1246 if (logging_mode & LOG_MODE_FILE)
1248 if (!*file_path) set_file_path(NULL);
1249 panic_recurseflag = TRUE;
1250 open_log(&paniclogfd, lt_panic, NULL); /* Won't return on failure */
1251 panic_recurseflag = FALSE;
1253 if (panic_save_buffer)
1254 (void) write(paniclogfd, panic_save_buffer, Ustrlen(panic_save_buffer));
1256 written_len = write_to_fd_buf(paniclogfd, g->s, g->ptr);
1257 if (written_len != g->ptr)
1259 int save_errno = errno;
1260 write_syslog(LOG_CRIT, log_buffer);
1261 sprintf(CS log_buffer, "write failed on panic log: length=%d result=%d "
1262 "errno=%d (%s)", g->ptr, (int)written_len, save_errno, strerror(save_errno));
1263 write_syslog(LOG_CRIT, string_from_gstring(g));
1264 flags |= LOG_PANIC_DIE;
1267 (void)close(paniclogfd);
1270 /* Give up if the DIE flag is set */
1272 if ((flags & LOG_PANIC_DIE) != LOG_PANIC)
1273 die(NULL, US"Unexpected failure, please try later");
1279 /*************************************************
1280 * Close any open log files *
1281 *************************************************/
1287 { (void)close(mainlogfd); mainlogfd = -1; }
1288 if (rejectlogfd >= 0)
1289 { (void)close(rejectlogfd); rejectlogfd = -1; }
1291 syslog_open = FALSE;
1296 /*************************************************
1297 * Multi-bit set or clear *
1298 *************************************************/
1300 /* These functions take a list of bit indexes (terminated by -1) and
1301 clear or set the corresponding bits in the selector.
1304 selector address of the bit string
1305 selsize number of words in the bit string
1306 bits list of bits to set
1310 bits_clear(unsigned int *selector, size_t selsize, int *bits)
1312 for(; *bits != -1; ++bits)
1313 BIT_CLEAR(selector, selsize, *bits);
1317 bits_set(unsigned int *selector, size_t selsize, int *bits)
1319 for(; *bits != -1; ++bits)
1320 BIT_SET(selector, selsize, *bits);
1325 /*************************************************
1326 * Decode bit settings for log/debug *
1327 *************************************************/
1329 /* This function decodes a string containing bit settings in the form of +name
1330 and/or -name sequences, and sets/unsets bits in a bit string accordingly. It
1331 also recognizes a numeric setting of the form =<number>, but this is not
1332 intended for user use. It's an easy way for Exim to pass the debug settings
1333 when it is re-exec'ed.
1335 The option table is a list of names and bit indexes. The index -1
1336 means "set all bits, except for those listed in notall". The notall
1337 list is terminated by -1.
1339 The action taken for bad values varies depending upon why we're here.
1340 For log messages, or if the debugging is triggered from config, then we write
1341 to the log on the way out. For debug setting triggered from the command-line,
1342 we treat it as an unknown option: error message to stderr and die.
1345 selector address of the bit string
1346 selsize number of words in the bit string
1347 notall list of bits to exclude from "all"
1348 string the configured string
1349 options the table of option names
1351 which "log" or "debug"
1352 flags DEBUG_FROM_CONFIG
1354 Returns: nothing on success - bomb out on failure
1358 decode_bits(unsigned int *selector, size_t selsize, int *notall,
1359 uschar *string, bit_table *options, int count, uschar *which, int flags)
1362 if (!string) return;
1366 char *end; /* Not uschar */
1367 memset(selector, 0, sizeof(*selector)*selsize);
1368 *selector = strtoul(CS string+1, &end, 0);
1370 errmsg = string_sprintf("malformed numeric %s_selector setting: %s", which,
1375 /* Handle symbolic setting */
1382 bit_table *start, *end;
1384 Uskip_whitespace(&string);
1385 if (!*string) return;
1387 if (*string != '+' && *string != '-')
1389 errmsg = string_sprintf("malformed %s_selector setting: "
1390 "+ or - expected but found \"%s\"", which, string);
1394 adding = *string++ == '+';
1396 while (isalnum(*string) || *string == '_') string++;
1400 end = options + count;
1404 bit_table *middle = start + (end - start)/2;
1405 int c = Ustrncmp(s, middle->name, len);
1407 if (middle->name[len] != 0) c = -1; else
1409 unsigned int bit = middle->bit;
1415 memset(selector, -1, sizeof(*selector)*selsize);
1416 bits_clear(selector, selsize, notall);
1419 memset(selector, 0, sizeof(*selector)*selsize);
1422 BIT_SET(selector, selsize, bit);
1424 BIT_CLEAR(selector, selsize, bit);
1426 break; /* Out of loop to match selector name */
1428 if (c < 0) end = middle; else start = middle + 1;
1429 } /* Loop to match selector name */
1433 errmsg = string_sprintf("unknown %s_selector setting: %c%.*s", which,
1434 adding? '+' : '-', len, s);
1437 } /* Loop for selector names */
1439 /* Handle disasters */
1442 if (Ustrcmp(which, "debug") == 0)
1444 if (flags & DEBUG_FROM_CONFIG)
1446 log_write(0, LOG_CONFIG|LOG_PANIC, "%s", errmsg);
1449 fprintf(stderr, "exim: %s\n", errmsg);
1452 else log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "%s", errmsg);
1457 /*************************************************
1458 * Activate a debug logfile (late) *
1459 *************************************************/
1461 /* Normally, debugging is activated from the command-line; it may be useful
1462 within the configuration to activate debugging later, based on certain
1463 conditions. If debugging is already in progress, we return early, no action
1464 taken (besides debug-logging that we wanted debug-logging).
1466 Failures in options are not fatal but will result in paniclog entries for the
1469 The first use of this is in ACL logic, "control = debug/tag=foo/opts=+expand"
1470 which can be combined with conditions, etc, to activate extra logging only
1471 for certain sources. The second use is inetd wait mode debug preservation. */
1474 debug_logging_activate(uschar *tag_name, uschar *opts)
1480 debug_printf("DEBUGGING ACTIVATED FROM WITHIN CONFIG.\n"
1481 "DEBUG: Tag=\"%s\" opts=\"%s\"\n", tag_name, opts ? opts : US"");
1485 if (tag_name != NULL && (Ustrchr(tag_name, '/') != NULL))
1487 log_write(0, LOG_MAIN|LOG_PANIC, "debug tag may not contain a '/' in: %s",
1492 debug_selector = D_default;
1494 decode_bits(&debug_selector, 1, debug_notall, opts,
1495 debug_options, debug_options_count, US"debug", DEBUG_FROM_CONFIG);
1497 /* When activating from a transport process we may never have logged at all
1498 resulting in certain setup not having been done. Hack this for now so we
1499 do not segfault; note that nondefault log locations will not work */
1501 if (!*file_path) set_file_path(NULL);
1503 open_log(&fd, lt_debug, tag_name);
1506 debug_file = fdopen(fd, "w");
1508 log_write(0, LOG_MAIN|LOG_PANIC, "unable to open debug log");
1513 debug_logging_stop(void)
1515 if (!debug_file || !debuglog_name[0]) return;
1520 unlink_log(lt_debug);
1523 /* Called from the appendfile transport setup. */
1527 set_file_path(NULL);
1528 if (!(logging_mode & LOG_MODE_FILE)) return;
1529 open_log(&mainlogfd, lt_main, 0);
1530 open_log(&rejectlogfd, lt_reject, 0);