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_open_already_exim(uschar * const name)
271 const int flags = O_WRONLY | O_APPEND | O_CREAT | O_NONBLOCK;
273 if (geteuid() != exim_uid)
279 fd = Uopen(name, flags, LOG_MODE);
281 /* If creation failed, attempt to build a log directory in case that is the
284 if (fd < 0 && errno == ENOENT)
287 uschar *lastslash = Ustrrchr(name, '/');
289 created = directory_make(NULL, name, LOG_DIRECTORY_MODE, FALSE);
290 DEBUG(D_any) debug_printf("%s log directory %s\n",
291 created ? "created" : "failed to create", name);
293 if (created) fd = Uopen(name, flags, LOG_MODE);
301 /* Inspired by OpenSSH's mm_send_fd(). Thanks! */
304 log_send_fd(const int sock, const int fd)
309 char buf[CMSG_SPACE(sizeof(int))];
311 struct cmsghdr *cmsg;
316 memset(&msg, 0, sizeof(msg));
317 memset(&cmsgbuf, 0, sizeof(cmsgbuf));
318 msg.msg_control = &cmsgbuf.buf;
319 msg.msg_controllen = sizeof(cmsgbuf.buf);
321 cmsg = CMSG_FIRSTHDR(&msg);
322 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
323 cmsg->cmsg_level = SOL_SOCKET;
324 cmsg->cmsg_type = SCM_RIGHTS;
325 *(int *)CMSG_DATA(cmsg) = fd;
332 while ((n = sendmsg(sock, &msg, 0)) == -1 && errno == EINTR);
333 if (n != 1) return -1;
337 /* Inspired by OpenSSH's mm_receive_fd(). Thanks! */
340 log_recv_fd(const int sock)
345 char buf[CMSG_SPACE(sizeof(int))];
347 struct cmsghdr *cmsg;
353 memset(&msg, 0, sizeof(msg));
359 memset(&cmsgbuf, 0, sizeof(cmsgbuf));
360 msg.msg_control = &cmsgbuf.buf;
361 msg.msg_controllen = sizeof(cmsgbuf.buf);
363 while ((n = recvmsg(sock, &msg, 0)) == -1 && errno == EINTR);
364 if (n != 1 || ch != 'A') return -1;
366 cmsg = CMSG_FIRSTHDR(&msg);
367 if (cmsg == NULL) return -1;
368 if (cmsg->cmsg_type != SCM_RIGHTS) return -1;
369 fd = *(const int *)CMSG_DATA(cmsg);
370 if (fd < 0) return -1;
376 /*************************************************
377 * Create a log file as the exim user *
378 *************************************************/
380 /* This function is called when we are root to spawn an exim:exim subprocess
381 in which we can create a log file. It must be signal-safe since it is called
382 by the usr1_handler().
387 Returns: a file descriptor, or < 0 on failure (errno set)
391 log_open_as_exim(uschar * const name)
394 const uid_t euid = geteuid();
396 if (euid == exim_uid)
398 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 = exim_fork(US"logfile-open");
408 (void)close(sock[0]);
409 if (setgroups(1, &exim_gid) != 0) _exit(EXIT_FAILURE);
410 if (setgid(exim_gid) != 0) _exit(EXIT_FAILURE);
411 if (setuid(exim_uid) != 0) _exit(EXIT_FAILURE);
413 if (getuid() != exim_uid || geteuid() != exim_uid) _exit(EXIT_FAILURE);
414 if (getgid() != exim_gid || getegid() != exim_gid) _exit(EXIT_FAILURE);
416 fd = log_open_already_exim(name);
417 if (fd < 0) _exit(EXIT_FAILURE);
418 if (log_send_fd(sock[1], fd) != 0) _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);
452 /*************************************************
454 *************************************************/
456 /* This function opens one of a number of logs, creating the log directory if
457 it does not exist. This may be called recursively on failure, in order to open
460 The directory is in the static variable file_path. This is static so that it
461 the work of sorting out the path is done just once per Exim process.
463 Exim is normally configured to avoid running as root wherever possible, the log
464 files must be owned by the non-privileged exim user. To ensure this, first try
465 an open without O_CREAT - most of the time this will succeed. If it fails, try
466 to create the file; if running as root, this must be done in a subprocess to
470 fd where to return the resulting file descriptor
471 type lt_main, lt_reject, lt_panic, or lt_debug
472 tag optional tag to include in the name (only hooked up for debug)
478 open_log(int *fd, int type, uschar *tag)
482 uschar buffer[LOG_NAME_SIZE];
484 /* The names of the log files are controlled by file_path. The panic log is
485 written to the same directory as the main and reject logs, but its name does
486 not have a datestamp. The use of datestamps is indicated by %D/%M in file_path.
487 When opening the panic log, if %D or %M is present, we remove the datestamp
488 from the generated name; if it is at the start, remove a following
489 non-alphanumeric character as well; otherwise, remove a preceding
490 non-alphanumeric character. This is definitely kludgy, but it sort of does what
491 people want, I hope. */
493 ok = string_format(buffer, sizeof(buffer), CS file_path, log_names[type]);
498 /* Save the name of the mainlog for rollover processing. Without a datestamp,
499 it gets statted to see if it has been cycled. With a datestamp, the datestamp
500 will be compared. The static slot for saving it is the same size as buffer,
501 and the text has been checked above to fit, so this use of strcpy() is OK. */
502 Ustrcpy(mainlog_name, buffer);
503 if (string_datestamp_offset > 0)
504 mainlog_datestamp = mainlog_name + string_datestamp_offset;
506 /* Ditto for the reject log */
507 Ustrcpy(rejectlog_name, buffer);
508 if (string_datestamp_offset > 0)
509 rejectlog_datestamp = rejectlog_name + string_datestamp_offset;
511 /* and deal with the debug log (which keeps the datestamp, but does not
513 Ustrcpy(debuglog_name, buffer);
516 /* this won't change the offset of the datestamp */
517 ok2 = string_format(buffer, sizeof(buffer), "%s%s",
520 Ustrcpy(debuglog_name, buffer);
523 /* Remove any datestamp if this is the panic log. This is rare, so there's no
524 need to optimize getting the datestamp length. We remove one non-alphanumeric
525 char afterwards if at the start, otherwise one before. */
526 if (string_datestamp_offset >= 0)
528 uschar * from = buffer + string_datestamp_offset;
529 uschar * to = from + string_datestamp_length;
531 if (from == buffer || from[-1] == '/')
533 if (!isalnum(*to)) to++;
536 if (!isalnum(from[-1])) from--;
538 /* This copy is ok, because we know that to is a substring of from. But
539 due to overlap we must use memmove() not Ustrcpy(). */
540 memmove(from, to, Ustrlen(to)+1);
544 /* If the file name is too long, it is an unrecoverable disaster */
547 die(US"exim: log file path too long: aborting",
548 US"Logging failure; please try later");
550 /* We now have the file name. After a successful open, return. */
552 *fd = log_open_as_exim(buffer);
561 /* Creation failed. There are some circumstances in which we get here when
562 the effective uid is not root or exim, which is the problem. (For example, a
563 non-setuid binary with log_arguments set, called in certain ways.) Rather than
564 just bombing out, force the log to stderr and carry on if stderr is available.
567 if (euid != root_uid && euid != exim_uid && log_stderr)
569 *fd = fileno(log_stderr);
573 /* Otherwise this is a disaster. This call is deliberately ONLY to the panic
574 log. If possible, save a copy of the original line that was being logged. If we
575 are recursing (can't open the panic log either), the pointer will already be
576 set. Also, when we had to use a subprocess for the create we didn't retrieve
577 errno from it, so get the error from the open attempt above (which is often
578 meaningful enough, so leave it). */
580 if (!panic_save_buffer)
581 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
582 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
584 log_write(0, LOG_PANIC_DIE, "Cannot open %s log file \"%s\": %s: "
585 "euid=%d egid=%d", log_names[type], buffer, strerror(errno), euid, getegid());
593 if (type == lt_debug) unlink(CS debuglog_name);
598 /*************************************************
599 * Add configuration file info to log line *
600 *************************************************/
602 /* This is put in a function because it's needed twice (once for debugging,
606 ptr pointer to the end of the line we are building
609 Returns: updated pointer
613 log_config_info(gstring * g, int flags)
615 g = string_cat(g, US"Exim configuration error");
617 if (flags & (LOG_CONFIG_FOR & ~LOG_CONFIG))
618 return string_cat(g, US" for ");
620 if (flags & (LOG_CONFIG_IN & ~LOG_CONFIG))
621 g = string_fmt_append(g, " in line %d of %s", config_lineno, config_filename);
623 return string_catn(g, US":\n ", 4);
627 /*************************************************
628 * A write() operation failed *
629 *************************************************/
631 /* This function is called when write() fails on anything other than the panic
632 log, which can happen if a disk gets full or a file gets too large or whatever.
633 We try to save the relevant message in the panic_save buffer before crashing
636 The potential invoker should probably not call us for EINTR -1 writes. But
637 otherwise, short writes are bad as we don't do non-blocking writes to fds
638 subject to flow control. (If we do, that's new and the logic of this should
642 name the name of the log being written
643 length the string length being written
644 rc the return value from write()
646 Returns: does not return
650 log_write_failed(uschar *name, int length, int rc)
652 int save_errno = errno;
654 if (!panic_save_buffer)
655 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
656 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
658 log_write(0, LOG_PANIC_DIE, "failed to write to %s: length=%d result=%d "
659 "errno=%d (%s)", name, length, rc, save_errno,
660 (save_errno == 0)? "write incomplete" : strerror(save_errno));
666 /*************************************************
667 * Write to an fd, retrying after signals *
668 *************************************************/
670 /* Basic write to fd for logs, handling EINTR.
673 fd the fd to write to
674 buf the string to write
675 length the string length being written
678 length actually written, persisting an errno from write()
681 write_to_fd_buf(int fd, const uschar *buf, size_t length)
684 size_t total_written = 0;
685 const uschar *p = buf;
686 size_t left = length;
690 wrote = write(fd, p, left);
691 if (wrote == (ssize_t)-1)
693 if (errno == EINTR) continue;
696 total_written += wrote;
705 return total_written;
710 set_file_path(BOOL *multiple)
713 int sep = ':'; /* Fixed separator - outside use */
714 const uschar *ss = *log_file_path ? log_file_path : US LOG_FILE_PATH;
717 while ((s = string_nextinlist(&ss, &sep, log_buffer, LOG_BUFFER_SIZE)))
719 if (Ustrcmp(s, "syslog") == 0)
720 logging_mode |= LOG_MODE_SYSLOG;
721 else if (logging_mode & LOG_MODE_FILE) /* we know a file already */
723 if (multiple) *multiple = TRUE;
727 logging_mode |= LOG_MODE_FILE;
729 /* If a non-empty path is given, use it */
732 file_path = string_copy(s);
734 /* If the path is empty, we want to use the first non-empty, non-
735 syslog item in LOG_FILE_PATH, if there is one, since the value of
736 log_file_path may have been set at runtime. If there is no such item,
737 use the ultimate default in the spool directory. */
746 /* avoid closing it if it is closed already or if we do not see a chance
747 to open the file mainlog later again */
748 if (mainlogfd < 0 /* already closed */
749 || !(geteuid() == 0 || geteuid() == exim_uid))
751 (void)close(mainlogfd);
756 /*************************************************
757 * Write message to log file *
758 *************************************************/
760 /* Exim can be configured to log to local files, or use syslog, or both. This
761 is controlled by the setting of log_file_path. The following cases are
764 log_file_path = "" write files in the spool/log directory
765 log_file_path = "xxx" write files in the xxx directory
766 log_file_path = "syslog" write to syslog
767 log_file_path = "syslog : xxx" write to syslog and to files (any order)
769 The message always gets '\n' added on the end of it, since more than one
770 process may be writing to the log at once and we don't want intermingling to
771 happen in the middle of lines. To be absolutely sure of this we write the data
772 into a private buffer and then put it out in a single write() call.
774 The flags determine which log(s) the message is written to, or for syslogging,
775 which priority to use, and in the case of the panic log, whether the process
776 should die afterwards.
778 The variable really_exim is TRUE only when exim is running in privileged state
779 (i.e. not with a changed configuration or with testing options such as -brw).
780 If it is not, don't try to write to the log because permission will probably be
783 Avoid actually writing to the logs when exim is called with -bv or -bt to
784 test an address, but take other actions, such as panicking.
786 In Exim proper, the buffer for building the message is got at start-up, so that
787 nothing gets done if it can't be got. However, some functions that are also
788 used in utilities occasionally obey log_write calls in error situations, and it
789 is simplest to put a single malloc() here rather than put one in each utility.
790 Malloc is used directly because the store functions may call log_write().
792 If a message_id exists, we include it after the timestamp.
795 selector write to main log or LOG_INFO only if this value is zero, or if
796 its bit is set in log_selector[0]
797 flags each bit indicates some independent action:
798 LOG_SENDER add raw sender to the message
799 LOG_RECIPIENTS add raw recipients list to message
800 LOG_CONFIG add "Exim configuration error"
801 LOG_CONFIG_FOR add " for " instead of ":\n "
802 LOG_CONFIG_IN add " in line x[ of file y]"
803 LOG_MAIN write to main log or syslog LOG_INFO
804 LOG_REJECT write to reject log or syslog LOG_NOTICE
805 LOG_PANIC write to panic log or syslog LOG_ALERT
806 LOG_PANIC_DIE write to panic log or LOG_ALERT and then crash
807 format a printf() format
808 ... arguments for format
814 log_write(unsigned int selector, int flags, const char *format, ...)
818 gstring gs = { .size = LOG_BUFFER_SIZE-1, .ptr = 0, .s = log_buffer };
822 /* If panic_recurseflag is set, we have failed to open the panic log. This is
823 the ultimate disaster. First try to write the message to a debug file and/or
824 stderr and also to syslog. If panic_save_buffer is not NULL, it contains the
825 original log line that caused the problem. Afterwards, expire. */
827 if (panic_recurseflag)
829 uschar *extra = panic_save_buffer ? panic_save_buffer : US"";
830 if (debug_file) debug_printf("%s%s", extra, log_buffer);
831 if (log_stderr && log_stderr != debug_file)
832 fprintf(log_stderr, "%s%s", extra, log_buffer);
833 if (*extra) write_syslog(LOG_CRIT, extra);
834 write_syslog(LOG_CRIT, log_buffer);
835 die(US"exim: could not open panic log - aborting: see message(s) above",
836 US"Unexpected log failure, please try later");
839 /* Ensure we have a buffer (see comment above); this should never be obeyed
840 when running Exim proper, only when running utilities. */
843 if (!(log_buffer = US malloc(LOG_BUFFER_SIZE)))
845 fprintf(stderr, "exim: failed to get store for log buffer\n");
846 exim_exit(EXIT_FAILURE);
849 /* If we haven't already done so, inspect the setting of log_file_path to
850 determine whether to log to files and/or to syslog. Bits in logging_mode
851 control this, and for file logging, the path must end up in file_path. This
852 variable must be in permanent store because it may be required again later in
857 BOOL multiple = FALSE;
858 int old_pool = store_pool;
860 store_pool = POOL_PERM;
862 /* If nothing has been set, don't waste effort... the default values for the
863 statics are file_path="" and logging_mode = LOG_MODE_FILE. */
865 if (*log_file_path) set_file_path(&multiple);
867 /* If no modes have been selected, it is a major disaster */
869 if (logging_mode == 0)
870 die(US"Neither syslog nor file logging set in log_file_path",
871 US"Unexpected logging failure");
873 /* Set up the ultimate default if necessary. Then revert to the old store
874 pool, and record that we've sorted out the path. */
876 if (logging_mode & LOG_MODE_FILE && !file_path[0])
877 file_path = string_sprintf("%s/log/%%slog", spool_directory);
878 store_pool = old_pool;
879 path_inspected = TRUE;
881 /* If more than one file path was given, log a complaint. This recursive call
882 should work since we have now set up the routing. */
885 log_write(0, LOG_MAIN|LOG_PANIC,
886 "More than one path given in log_file_path: using %s", file_path);
889 /* If debugging, show all log entries, but don't show headers. Do it all
890 in one go so that it doesn't get split when multi-processing. */
896 g = string_catn(&gs, US"LOG:", 4);
898 /* Show the selector that was passed into the call. */
900 for (i = 0; i < log_options_count; i++)
902 unsigned int bitnum = log_options[i].bit;
903 if (bitnum < BITWORDSIZE && selector == BIT(bitnum))
904 g = string_fmt_append(g, " %s", log_options[i].name);
907 g = string_fmt_append(g, "%s%s%s%s\n ",
908 flags & LOG_MAIN ? " MAIN" : "",
909 flags & LOG_PANIC ? " PANIC" : "",
910 (flags & LOG_PANIC_DIE) == LOG_PANIC_DIE ? " DIE" : "",
911 flags & LOG_REJECT ? " REJECT" : "");
913 if (flags & LOG_CONFIG) g = log_config_info(g, flags);
915 /* We want to be able to log tainted info, but log_buffer is directly
916 malloc'd. So use deliberately taint-nonchecking routines to build into
917 it, trusting that we will never expand the results. */
919 va_start(ap, format);
921 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
924 g = string_cat(g, US"**** log string overflowed log buffer ****");
928 g->size = LOG_BUFFER_SIZE;
929 g = string_catn(g, US"\n", 1);
930 debug_printf("%s", string_from_gstring(g));
932 gs.size = LOG_BUFFER_SIZE-1; /* Having used the buffer for debug output, */
933 gs.ptr = 0; /* reset it for the real use. */
936 /* If no log file is specified, we are in a mess. */
938 if (!(flags & (LOG_MAIN|LOG_PANIC|LOG_REJECT)))
939 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "log_write called with no log "
942 /* There are some weird circumstances in which logging is disabled. */
944 if (f.disable_logging)
946 DEBUG(D_any) debug_printf("log writing disabled\n");
947 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
951 /* Handle disabled reject log */
953 if (!write_rejectlog) flags &= ~LOG_REJECT;
955 /* Create the main message in the log buffer. Do not include the message id
956 when called by a utility. */
958 g = string_fmt_append(&gs, "%s ", tod_stamp(tod_log));
962 if (!syslog_pid) pid_position[0] = g->ptr; /* remember begin … */
963 g = string_fmt_append(g, "[%d] ", (int)getpid());
964 if (!syslog_pid) pid_position[1] = g->ptr; /* … and end+1 of the PID */
967 if (f.really_exim && message_id[0] != 0)
968 g = string_fmt_append(g, "%s ", message_id);
970 if (flags & LOG_CONFIG)
971 g = log_config_info(g, flags);
973 va_start(ap, format);
977 /* We want to be able to log tainted info, but log_buffer is directly
978 malloc'd. So use deliberately taint-nonchecking routines to build into
979 it, trusting that we will never expand the results. */
981 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
984 g = string_cat(g, US"**** log string overflowed log buffer ****\n");
989 /* Add the raw, unrewritten, sender to the message if required. This is done
990 this way because it kind of fits with LOG_RECIPIENTS. */
992 if ( flags & LOG_SENDER
993 && g->ptr < LOG_BUFFER_SIZE - 10 - Ustrlen(raw_sender))
994 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " from <%s>", raw_sender);
996 /* Add list of recipients to the message if required; the raw list,
997 before rewriting, was saved in raw_recipients. There may be none, if an ACL
998 discarded them all. */
1000 if ( flags & LOG_RECIPIENTS
1001 && g->ptr < LOG_BUFFER_SIZE - 6
1002 && raw_recipients_count > 0)
1005 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " for", NULL);
1006 for (i = 0; i < raw_recipients_count; i++)
1008 uschar * s = raw_recipients[i];
1009 if (LOG_BUFFER_SIZE - g->ptr < Ustrlen(s) + 3) break;
1010 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " %s", s);
1014 g = string_catn(g, US"\n", 1);
1015 string_from_gstring(g);
1017 /* Handle loggable errors when running a utility, or when address testing.
1018 Write to log_stderr unless debugging (when it will already have been written),
1019 or unless there is no log_stderr (expn called from daemon, for example). */
1021 if (!f.really_exim || f.log_testing_mode)
1023 if ( !debug_selector
1025 && (selector == 0 || (selector & log_selector[0]) != 0)
1028 fprintf(log_stderr, "LOG: %s", CS(log_buffer + 20)); /* no timestamp */
1030 fprintf(log_stderr, "%s", CS log_buffer);
1032 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
1036 /* Handle the main log. We know that either syslog or file logging (or both) is
1037 set up. A real file gets left open during reception or delivery once it has
1038 been opened, but we don't want to keep on writing to it for too long after it
1039 has been renamed. Therefore, do a stat() and see if the inode has changed, and
1042 if ( flags & LOG_MAIN
1043 && (!selector || selector & log_selector[0]))
1045 if ( logging_mode & LOG_MODE_SYSLOG
1046 && (syslog_duplication || !(flags & (LOG_REJECT|LOG_PANIC))))
1047 write_syslog(LOG_INFO, log_buffer);
1049 if (logging_mode & LOG_MODE_FILE)
1051 struct stat statbuf;
1053 /* Check for a change to the mainlog file name when datestamping is in
1054 operation. This happens at midnight, at which point we want to roll over
1055 the file. Closing it has the desired effect. */
1057 if (mainlog_datestamp)
1059 uschar *nowstamp = tod_stamp(string_datestamp_type);
1060 if (Ustrncmp (mainlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1062 (void)close(mainlogfd); /* Close the file */
1063 mainlogfd = -1; /* Clear the file descriptor */
1064 mainlog_inode = 0; /* Unset the inode */
1065 mainlog_datestamp = NULL; /* Clear the datestamp */
1069 /* Otherwise, we want to check whether the file has been renamed by a
1070 cycling script. This could be "if else", but for safety's sake, leave it as
1071 "if" so that renaming the log starts a new file even when datestamping is
1075 if (Ustat(mainlog_name, &statbuf) < 0 || statbuf.st_ino != mainlog_inode)
1078 /* If the log is closed, open it. Then write the line. */
1082 open_log(&mainlogfd, lt_main, NULL); /* No return on error */
1083 if (fstat(mainlogfd, &statbuf) >= 0) mainlog_inode = statbuf.st_ino;
1086 /* Failing to write to the log is disastrous */
1088 written_len = write_to_fd_buf(mainlogfd, g->s, g->ptr);
1089 if (written_len != g->ptr)
1091 log_write_failed(US"main log", g->ptr, written_len);
1092 /* That function does not return */
1097 /* Handle the log for rejected messages. This can be globally disabled, in
1098 which case the flags are altered above. If there are any header lines (i.e. if
1099 the rejection is happening after the DATA phase), log the recipients and the
1102 if (flags & LOG_REJECT)
1104 if (header_list && LOGGING(rejected_header))
1109 if (recipients_count > 0)
1111 /* List the sender */
1113 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1114 "Envelope-from: <%s>\n", sender_address);
1117 /* List up to 5 recipients */
1119 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1120 "Envelope-to: <%s>\n", recipients_list[0].address);
1123 for (i = 1; i < recipients_count && i < 5; i++)
1125 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1126 " <%s>\n", recipients_list[i].address);
1130 if (i < recipients_count)
1132 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " ...\n", NULL);
1137 /* A header with a NULL text is an unfilled in Received: header */
1139 for (header_line * h = header_list; h; h = h->next) if (h->text)
1141 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1142 "%c %s", h->type, h->text);
1145 else /* Buffer is full; truncate */
1147 g->ptr -= 100; /* For message and separator */
1148 if (g->s[g->ptr-1] == '\n') g->ptr--;
1149 g = string_cat(g, US"\n*** truncated ***\n");
1155 /* Write to syslog or to a log file */
1157 if ( logging_mode & LOG_MODE_SYSLOG
1158 && (syslog_duplication || !(flags & LOG_PANIC)))
1159 write_syslog(LOG_NOTICE, string_from_gstring(g));
1161 /* Check for a change to the rejectlog file name when datestamping is in
1162 operation. This happens at midnight, at which point we want to roll over
1163 the file. Closing it has the desired effect. */
1165 if (logging_mode & LOG_MODE_FILE)
1167 struct stat statbuf;
1169 if (rejectlog_datestamp)
1171 uschar *nowstamp = tod_stamp(string_datestamp_type);
1172 if (Ustrncmp (rejectlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1174 (void)close(rejectlogfd); /* Close the file */
1175 rejectlogfd = -1; /* Clear the file descriptor */
1176 rejectlog_inode = 0; /* Unset the inode */
1177 rejectlog_datestamp = NULL; /* Clear the datestamp */
1181 /* Otherwise, we want to check whether the file has been renamed by a
1182 cycling script. This could be "if else", but for safety's sake, leave it as
1183 "if" so that renaming the log starts a new file even when datestamping is
1186 if (rejectlogfd >= 0)
1187 if (Ustat(rejectlog_name, &statbuf) < 0 ||
1188 statbuf.st_ino != rejectlog_inode)
1190 (void)close(rejectlogfd);
1192 rejectlog_inode = 0;
1195 /* Open the file if necessary, and write the data */
1197 if (rejectlogfd < 0)
1199 open_log(&rejectlogfd, lt_reject, NULL); /* No return on error */
1200 if (fstat(rejectlogfd, &statbuf) >= 0) rejectlog_inode = statbuf.st_ino;
1203 written_len = write_to_fd_buf(rejectlogfd, g->s, g->ptr);
1204 if (written_len != g->ptr)
1206 log_write_failed(US"reject log", g->ptr, written_len);
1207 /* That function does not return */
1213 /* Handle the panic log, which is not kept open like the others. If it fails to
1214 open, there will be a recursive call to log_write(). We detect this above and
1215 attempt to write to the system log as a last-ditch try at telling somebody. In
1216 all cases except mua_wrapper, try to write to log_stderr. */
1218 if (flags & LOG_PANIC)
1220 if (log_stderr && log_stderr != debug_file && !mua_wrapper)
1221 fprintf(log_stderr, "%s", CS string_from_gstring(g));
1223 if (logging_mode & LOG_MODE_SYSLOG)
1224 write_syslog(LOG_ALERT, log_buffer);
1226 /* If this panic logging was caused by a failure to open the main log,
1227 the original log line is in panic_save_buffer. Make an attempt to write it. */
1229 if (logging_mode & LOG_MODE_FILE)
1231 panic_recurseflag = TRUE;
1232 open_log(&paniclogfd, lt_panic, NULL); /* Won't return on failure */
1233 panic_recurseflag = FALSE;
1235 if (panic_save_buffer)
1237 int i = write(paniclogfd, panic_save_buffer, Ustrlen(panic_save_buffer));
1238 i = i; /* compiler quietening */
1241 written_len = write_to_fd_buf(paniclogfd, g->s, g->ptr);
1242 if (written_len != g->ptr)
1244 int save_errno = errno;
1245 write_syslog(LOG_CRIT, log_buffer);
1246 sprintf(CS log_buffer, "write failed on panic log: length=%d result=%d "
1247 "errno=%d (%s)", g->ptr, (int)written_len, save_errno, strerror(save_errno));
1248 write_syslog(LOG_CRIT, string_from_gstring(g));
1249 flags |= LOG_PANIC_DIE;
1252 (void)close(paniclogfd);
1255 /* Give up if the DIE flag is set */
1257 if ((flags & LOG_PANIC_DIE) != LOG_PANIC)
1258 die(NULL, US"Unexpected failure, please try later");
1264 /*************************************************
1265 * Close any open log files *
1266 *************************************************/
1272 { (void)close(mainlogfd); mainlogfd = -1; }
1273 if (rejectlogfd >= 0)
1274 { (void)close(rejectlogfd); rejectlogfd = -1; }
1276 syslog_open = FALSE;
1281 /*************************************************
1282 * Multi-bit set or clear *
1283 *************************************************/
1285 /* These functions take a list of bit indexes (terminated by -1) and
1286 clear or set the corresponding bits in the selector.
1289 selector address of the bit string
1290 selsize number of words in the bit string
1291 bits list of bits to set
1295 bits_clear(unsigned int *selector, size_t selsize, int *bits)
1297 for(; *bits != -1; ++bits)
1298 BIT_CLEAR(selector, selsize, *bits);
1302 bits_set(unsigned int *selector, size_t selsize, int *bits)
1304 for(; *bits != -1; ++bits)
1305 BIT_SET(selector, selsize, *bits);
1310 /*************************************************
1311 * Decode bit settings for log/debug *
1312 *************************************************/
1314 /* This function decodes a string containing bit settings in the form of +name
1315 and/or -name sequences, and sets/unsets bits in a bit string accordingly. It
1316 also recognizes a numeric setting of the form =<number>, but this is not
1317 intended for user use. It's an easy way for Exim to pass the debug settings
1318 when it is re-exec'ed.
1320 The option table is a list of names and bit indexes. The index -1
1321 means "set all bits, except for those listed in notall". The notall
1322 list is terminated by -1.
1324 The action taken for bad values varies depending upon why we're here.
1325 For log messages, or if the debugging is triggered from config, then we write
1326 to the log on the way out. For debug setting triggered from the command-line,
1327 we treat it as an unknown option: error message to stderr and die.
1330 selector address of the bit string
1331 selsize number of words in the bit string
1332 notall list of bits to exclude from "all"
1333 string the configured string
1334 options the table of option names
1336 which "log" or "debug"
1337 flags DEBUG_FROM_CONFIG
1339 Returns: nothing on success - bomb out on failure
1343 decode_bits(unsigned int *selector, size_t selsize, int *notall,
1344 uschar *string, bit_table *options, int count, uschar *which, int flags)
1347 if (!string) return;
1351 char *end; /* Not uschar */
1352 memset(selector, 0, sizeof(*selector)*selsize);
1353 *selector = strtoul(CS string+1, &end, 0);
1355 errmsg = string_sprintf("malformed numeric %s_selector setting: %s", which,
1360 /* Handle symbolic setting */
1367 bit_table *start, *end;
1369 Uskip_whitespace(&string);
1370 if (!*string) return;
1372 if (*string != '+' && *string != '-')
1374 errmsg = string_sprintf("malformed %s_selector setting: "
1375 "+ or - expected but found \"%s\"", which, string);
1379 adding = *string++ == '+';
1381 while (isalnum(*string) || *string == '_') string++;
1385 end = options + count;
1389 bit_table *middle = start + (end - start)/2;
1390 int c = Ustrncmp(s, middle->name, len);
1392 if (middle->name[len] != 0) c = -1; else
1394 unsigned int bit = middle->bit;
1400 memset(selector, -1, sizeof(*selector)*selsize);
1401 bits_clear(selector, selsize, notall);
1404 memset(selector, 0, sizeof(*selector)*selsize);
1407 BIT_SET(selector, selsize, bit);
1409 BIT_CLEAR(selector, selsize, bit);
1411 break; /* Out of loop to match selector name */
1413 if (c < 0) end = middle; else start = middle + 1;
1414 } /* Loop to match selector name */
1418 errmsg = string_sprintf("unknown %s_selector setting: %c%.*s", which,
1419 adding? '+' : '-', len, s);
1422 } /* Loop for selector names */
1424 /* Handle disasters */
1427 if (Ustrcmp(which, "debug") == 0)
1429 if (flags & DEBUG_FROM_CONFIG)
1431 log_write(0, LOG_CONFIG|LOG_PANIC, "%s", errmsg);
1434 fprintf(stderr, "exim: %s\n", errmsg);
1437 else log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "%s", errmsg);
1442 /*************************************************
1443 * Activate a debug logfile (late) *
1444 *************************************************/
1446 /* Normally, debugging is activated from the command-line; it may be useful
1447 within the configuration to activate debugging later, based on certain
1448 conditions. If debugging is already in progress, we return early, no action
1449 taken (besides debug-logging that we wanted debug-logging).
1451 Failures in options are not fatal but will result in paniclog entries for the
1454 The first use of this is in ACL logic, "control = debug/tag=foo/opts=+expand"
1455 which can be combined with conditions, etc, to activate extra logging only
1456 for certain sources. The second use is inetd wait mode debug preservation. */
1459 debug_logging_activate(uschar *tag_name, uschar *opts)
1465 debug_printf("DEBUGGING ACTIVATED FROM WITHIN CONFIG.\n"
1466 "DEBUG: Tag=\"%s\" opts=\"%s\"\n", tag_name, opts ? opts : US"");
1470 if (tag_name != NULL && (Ustrchr(tag_name, '/') != NULL))
1472 log_write(0, LOG_MAIN|LOG_PANIC, "debug tag may not contain a '/' in: %s",
1477 debug_selector = D_default;
1479 decode_bits(&debug_selector, 1, debug_notall, opts,
1480 debug_options, debug_options_count, US"debug", DEBUG_FROM_CONFIG);
1482 /* When activating from a transport process we may never have logged at all
1483 resulting in certain setup not having been done. Hack this for now so we
1484 do not segfault; note that nondefault log locations will not work */
1486 if (!*file_path) set_file_path(NULL);
1488 open_log(&fd, lt_debug, tag_name);
1491 debug_file = fdopen(fd, "w");
1493 log_write(0, LOG_MAIN|LOG_PANIC, "unable to open debug log");
1498 debug_logging_stop(void)
1500 if (!debug_file || !debuglog_name[0]) return;
1505 unlink_log(lt_debug);
1511 set_file_path(NULL);
1512 open_log(&mainlogfd, lt_main, 0);
1513 open_log(&rejectlogfd, lt_reject, 0);