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);
291 DEBUG(D_any) debug_printf("%s log directory %s\n",
292 created ? "created" : "failed to create", name);
294 if (created) fd = Uopen(name, flags, LOG_MODE);
302 /* Inspired by OpenSSH's mm_send_fd(). Thanks!
303 Send fd over socketpair.
304 Return: true iff good.
308 log_send_fd(const int sock, const int fd)
313 char buf[CMSG_SPACE(sizeof(int))];
315 struct cmsghdr *cmsg;
317 struct iovec vec = {.iov_base = &ch, .iov_len = 1};
320 memset(&msg, 0, sizeof(msg));
321 memset(&cmsgbuf, 0, sizeof(cmsgbuf));
322 msg.msg_control = &cmsgbuf.buf;
323 msg.msg_controllen = sizeof(cmsgbuf.buf);
325 cmsg = CMSG_FIRSTHDR(&msg);
326 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
327 cmsg->cmsg_level = SOL_SOCKET;
328 cmsg->cmsg_type = SCM_RIGHTS;
329 *(int *)CMSG_DATA(cmsg) = fd;
334 while ((n = sendmsg(sock, &msg, 0)) == -1 && errno == EINTR);
338 /* Inspired by OpenSSH's mm_receive_fd(). Thanks!
339 Return fd passed over socketpair, or -1 on error.
343 log_recv_fd(const int sock)
348 char buf[CMSG_SPACE(sizeof(int))];
350 struct cmsghdr *cmsg;
352 struct iovec vec = {.iov_base = &ch, .iov_len = 1};
356 memset(&msg, 0, sizeof(msg));
360 memset(&cmsgbuf, 0, sizeof(cmsgbuf));
361 msg.msg_control = &cmsgbuf.buf;
362 msg.msg_controllen = sizeof(cmsgbuf.buf);
364 while ((n = recvmsg(sock, &msg, 0)) == -1 && errno == EINTR) ;
365 if (n != 1 || ch != 'A') return -1;
367 if (!(cmsg = CMSG_FIRSTHDR(&msg))) return -1;
368 if (cmsg->cmsg_type != SCM_RIGHTS) return -1;
369 if ((fd = *(const int *)CMSG_DATA(cmsg)) < 0) return -1;
375 /*************************************************
376 * Create a log file as the exim user *
377 *************************************************/
379 /* This function is called when we are root to spawn an exim:exim subprocess
380 in which we can create a log file. It must be signal-safe since it is called
381 by the usr1_handler().
386 Returns: a file descriptor, or < 0 on failure (errno set)
390 log_open_as_exim(uschar * const name)
393 const uid_t euid = geteuid();
395 if (euid == exim_uid)
396 fd = log_open_already_exim(name);
397 else if (euid == root_uid)
400 if (socketpair(AF_UNIX, SOCK_STREAM, 0, sock) == 0)
402 const pid_t pid = fork();
405 (void)close(sock[0]);
406 if ( setgroups(1, &exim_gid) != 0
407 || setgid(exim_gid) != 0
408 || setuid(exim_uid) != 0
410 || getuid() != exim_uid || geteuid() != exim_uid
411 || getgid() != exim_gid || getegid() != exim_gid
413 || (fd = log_open_already_exim(name)) < 0
414 || !log_send_fd(sock[1], fd)
415 ) _exit(EXIT_FAILURE);
416 (void)close(sock[1]);
420 (void)close(sock[1]);
423 fd = log_recv_fd(sock[0]);
424 while (waitpid(pid, NULL, 0) == -1 && errno == EINTR);
426 (void)close(sock[0]);
433 flags = fcntl(fd, F_GETFD);
434 if (flags != -1) (void)fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
435 flags = fcntl(fd, F_GETFL);
436 if (flags != -1) (void)fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
447 /*************************************************
449 *************************************************/
451 /* This function opens one of a number of logs, creating the log directory if
452 it does not exist. This may be called recursively on failure, in order to open
455 The directory is in the static variable file_path. This is static so that it
456 the work of sorting out the path is done just once per Exim process.
458 Exim is normally configured to avoid running as root wherever possible, the log
459 files must be owned by the non-privileged exim user. To ensure this, first try
460 an open without O_CREAT - most of the time this will succeed. If it fails, try
461 to create the file; if running as root, this must be done in a subprocess to
465 fd where to return the resulting file descriptor
466 type lt_main, lt_reject, lt_panic, or lt_debug
467 tag optional tag to include in the name (only hooked up for debug)
473 open_log(int *fd, int type, uschar *tag)
477 uschar buffer[LOG_NAME_SIZE];
479 /* The names of the log files are controlled by file_path. The panic log is
480 written to the same directory as the main and reject logs, but its name does
481 not have a datestamp. The use of datestamps is indicated by %D/%M in file_path.
482 When opening the panic log, if %D or %M is present, we remove the datestamp
483 from the generated name; if it is at the start, remove a following
484 non-alphanumeric character as well; otherwise, remove a preceding
485 non-alphanumeric character. This is definitely kludgy, but it sort of does what
486 people want, I hope. */
488 ok = string_format(buffer, sizeof(buffer), CS file_path, log_names[type]);
490 /* Save the name of the mainlog for rollover processing. Without a datestamp,
491 it gets statted to see if it has been cycled. With a datestamp, the datestamp
492 will be compared. The static slot for saving it is the same size as buffer,
493 and the text has been checked above to fit, so this use of strcpy() is OK. */
497 Ustrcpy(mainlog_name, buffer);
498 if (string_datestamp_offset > 0)
499 mainlog_datestamp = mainlog_name + string_datestamp_offset;
502 /* Ditto for the reject log */
504 else if (type == lt_reject)
506 Ustrcpy(rejectlog_name, buffer);
507 if (string_datestamp_offset > 0)
508 rejectlog_datestamp = rejectlog_name + string_datestamp_offset;
511 /* and deal with the debug log (which keeps the datestamp, but does not
514 else if (type == lt_debug)
516 Ustrcpy(debuglog_name, buffer);
519 /* this won't change the offset of the datestamp */
520 ok2 = string_format(buffer, sizeof(buffer), "%s%s",
523 Ustrcpy(debuglog_name, buffer);
527 /* Remove any datestamp if this is the panic log. This is rare, so there's no
528 need to optimize getting the datestamp length. We remove one non-alphanumeric
529 char afterwards if at the start, otherwise one before. */
531 else if (string_datestamp_offset >= 0)
533 uschar * from = buffer + string_datestamp_offset;
534 uschar * to = from + string_datestamp_length;
536 if (from == buffer || from[-1] == '/')
538 if (!isalnum(*to)) to++;
541 if (!isalnum(from[-1])) from--;
543 /* This copy is ok, because we know that to is a substring of from. But
544 due to overlap we must use memmove() not Ustrcpy(). */
545 memmove(from, to, Ustrlen(to)+1);
548 /* If the file name is too long, it is an unrecoverable disaster */
551 die(US"exim: log file path too long: aborting",
552 US"Logging failure; please try later");
554 /* We now have the file name. After a successful open, return. */
556 *fd = log_open_as_exim(buffer);
565 /* Creation failed. There are some circumstances in which we get here when
566 the effective uid is not root or exim, which is the problem. (For example, a
567 non-setuid binary with log_arguments set, called in certain ways.) Rather than
568 just bombing out, force the log to stderr and carry on if stderr is available.
571 if (euid != root_uid && euid != exim_uid && log_stderr)
573 *fd = fileno(log_stderr);
577 /* Otherwise this is a disaster. This call is deliberately ONLY to the panic
578 log. If possible, save a copy of the original line that was being logged. If we
579 are recursing (can't open the panic log either), the pointer will already be
580 set. Also, when we had to use a subprocess for the create we didn't retrieve
581 errno from it, so get the error from the open attempt above (which is often
582 meaningful enough, so leave it). */
584 if (!panic_save_buffer)
585 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
586 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
588 log_write(0, LOG_PANIC_DIE, "Cannot open %s log file \"%s\": %s: "
589 "euid=%d egid=%d", log_names[type], buffer, strerror(errno), euid, getegid());
597 if (type == lt_debug) unlink(CS debuglog_name);
602 /*************************************************
603 * Add configuration file info to log line *
604 *************************************************/
606 /* This is put in a function because it's needed twice (once for debugging,
610 ptr pointer to the end of the line we are building
613 Returns: updated pointer
617 log_config_info(gstring * g, int flags)
619 g = string_cat(g, US"Exim configuration error");
621 if (flags & (LOG_CONFIG_FOR & ~LOG_CONFIG))
622 return string_cat(g, US" for ");
624 if (flags & (LOG_CONFIG_IN & ~LOG_CONFIG))
625 g = string_fmt_append(g, " in line %d of %s", config_lineno, config_filename);
627 return string_catn(g, US":\n ", 4);
631 /*************************************************
632 * A write() operation failed *
633 *************************************************/
635 /* This function is called when write() fails on anything other than the panic
636 log, which can happen if a disk gets full or a file gets too large or whatever.
637 We try to save the relevant message in the panic_save buffer before crashing
640 The potential invoker should probably not call us for EINTR -1 writes. But
641 otherwise, short writes are bad as we don't do non-blocking writes to fds
642 subject to flow control. (If we do, that's new and the logic of this should
646 name the name of the log being written
647 length the string length being written
648 rc the return value from write()
650 Returns: does not return
654 log_write_failed(uschar *name, int length, int rc)
656 int save_errno = errno;
658 if (!panic_save_buffer)
659 if ((panic_save_buffer = US malloc(LOG_BUFFER_SIZE)))
660 memcpy(panic_save_buffer, log_buffer, LOG_BUFFER_SIZE);
662 log_write(0, LOG_PANIC_DIE, "failed to write to %s: length=%d result=%d "
663 "errno=%d (%s)", name, length, rc, save_errno,
664 (save_errno == 0)? "write incomplete" : strerror(save_errno));
670 /*************************************************
671 * Write to an fd, retrying after signals *
672 *************************************************/
674 /* Basic write to fd for logs, handling EINTR.
677 fd the fd to write to
678 buf the string to write
679 length the string length being written
682 length actually written, persisting an errno from write()
685 write_to_fd_buf(int fd, const uschar *buf, size_t length)
688 size_t total_written = 0;
689 const uschar *p = buf;
690 size_t left = length;
694 wrote = write(fd, p, left);
695 if (wrote == (ssize_t)-1)
697 if (errno == EINTR) continue;
700 total_written += wrote;
709 return total_written;
717 int sep = ':'; /* Fixed separator - outside use */
719 const uschar *tt = US LOG_FILE_PATH;
720 while ((t = string_nextinlist(&tt, &sep, log_buffer, LOG_BUFFER_SIZE)))
722 if (Ustrcmp(t, "syslog") == 0 || t[0] == 0) continue;
723 file_path = string_copy(t);
732 if (mainlogfd < 0) return;
733 (void)close(mainlogfd);
738 /*************************************************
739 * Write message to log file *
740 *************************************************/
742 /* Exim can be configured to log to local files, or use syslog, or both. This
743 is controlled by the setting of log_file_path. The following cases are
746 log_file_path = "" write files in the spool/log directory
747 log_file_path = "xxx" write files in the xxx directory
748 log_file_path = "syslog" write to syslog
749 log_file_path = "syslog : xxx" write to syslog and to files (any order)
751 The message always gets '\n' added on the end of it, since more than one
752 process may be writing to the log at once and we don't want intermingling to
753 happen in the middle of lines. To be absolutely sure of this we write the data
754 into a private buffer and then put it out in a single write() call.
756 The flags determine which log(s) the message is written to, or for syslogging,
757 which priority to use, and in the case of the panic log, whether the process
758 should die afterwards.
760 The variable really_exim is TRUE only when exim is running in privileged state
761 (i.e. not with a changed configuration or with testing options such as -brw).
762 If it is not, don't try to write to the log because permission will probably be
765 Avoid actually writing to the logs when exim is called with -bv or -bt to
766 test an address, but take other actions, such as panicking.
768 In Exim proper, the buffer for building the message is got at start-up, so that
769 nothing gets done if it can't be got. However, some functions that are also
770 used in utilities occasionally obey log_write calls in error situations, and it
771 is simplest to put a single malloc() here rather than put one in each utility.
772 Malloc is used directly because the store functions may call log_write().
774 If a message_id exists, we include it after the timestamp.
777 selector write to main log or LOG_INFO only if this value is zero, or if
778 its bit is set in log_selector[0]
779 flags each bit indicates some independent action:
780 LOG_SENDER add raw sender to the message
781 LOG_RECIPIENTS add raw recipients list to message
782 LOG_CONFIG add "Exim configuration error"
783 LOG_CONFIG_FOR add " for " instead of ":\n "
784 LOG_CONFIG_IN add " in line x[ of file y]"
785 LOG_MAIN write to main log or syslog LOG_INFO
786 LOG_REJECT write to reject log or syslog LOG_NOTICE
787 LOG_PANIC write to panic log or syslog LOG_ALERT
788 LOG_PANIC_DIE write to panic log or LOG_ALERT and then crash
789 format a printf() format
790 ... arguments for format
796 log_write(unsigned int selector, int flags, const char *format, ...)
800 gstring gs = { .size = LOG_BUFFER_SIZE-1, .ptr = 0, .s = log_buffer };
804 /* If panic_recurseflag is set, we have failed to open the panic log. This is
805 the ultimate disaster. First try to write the message to a debug file and/or
806 stderr and also to syslog. If panic_save_buffer is not NULL, it contains the
807 original log line that caused the problem. Afterwards, expire. */
809 if (panic_recurseflag)
811 uschar *extra = panic_save_buffer ? panic_save_buffer : US"";
812 if (debug_file) debug_printf("%s%s", extra, log_buffer);
813 if (log_stderr && log_stderr != debug_file)
814 fprintf(log_stderr, "%s%s", extra, log_buffer);
815 if (*extra) write_syslog(LOG_CRIT, extra);
816 write_syslog(LOG_CRIT, log_buffer);
817 die(US"exim: could not open panic log - aborting: see message(s) above",
818 US"Unexpected log failure, please try later");
821 /* Ensure we have a buffer (see comment above); this should never be obeyed
822 when running Exim proper, only when running utilities. */
825 if (!(log_buffer = US malloc(LOG_BUFFER_SIZE)))
827 fprintf(stderr, "exim: failed to get store for log buffer\n");
828 exim_exit(EXIT_FAILURE);
831 /* If we haven't already done so, inspect the setting of log_file_path to
832 determine whether to log to files and/or to syslog. Bits in logging_mode
833 control this, and for file logging, the path must end up in file_path. This
834 variable must be in permanent store because it may be required again later in
839 BOOL multiple = FALSE;
840 int old_pool = store_pool;
842 store_pool = POOL_PERM;
844 /* If nothing has been set, don't waste effort... the default values for the
845 statics are file_path="" and logging_mode = LOG_MODE_FILE. */
849 int sep = ':'; /* Fixed separator - outside use */
851 const uschar *ss = log_file_path;
854 while ((s = string_nextinlist(&ss, &sep, log_buffer, LOG_BUFFER_SIZE)))
856 if (Ustrcmp(s, "syslog") == 0)
857 logging_mode |= LOG_MODE_SYSLOG;
858 else if (logging_mode & LOG_MODE_FILE)
862 logging_mode |= LOG_MODE_FILE;
864 /* If a non-empty path is given, use it */
867 file_path = string_copy(s);
869 /* If the path is empty, we want to use the first non-empty, non-
870 syslog item in LOG_FILE_PATH, if there is one, since the value of
871 log_file_path may have been set at runtime. If there is no such item,
872 use the ultimate default in the spool directory. */
875 set_file_path(); /* Empty item in log_file_path */
876 } /* First non-syslog item in log_file_path */
877 } /* Scan of log_file_path */
880 /* If no modes have been selected, it is a major disaster */
882 if (logging_mode == 0)
883 die(US"Neither syslog nor file logging set in log_file_path",
884 US"Unexpected logging failure");
886 /* Set up the ultimate default if necessary. Then revert to the old store
887 pool, and record that we've sorted out the path. */
889 if (logging_mode & LOG_MODE_FILE && !file_path[0])
890 file_path = string_sprintf("%s/log/%%slog", spool_directory);
891 store_pool = old_pool;
892 path_inspected = TRUE;
894 /* If more than one file path was given, log a complaint. This recursive call
895 should work since we have now set up the routing. */
898 log_write(0, LOG_MAIN|LOG_PANIC,
899 "More than one path given in log_file_path: using %s", file_path);
902 /* If debugging, show all log entries, but don't show headers. Do it all
903 in one go so that it doesn't get split when multi-processing. */
909 g = string_catn(&gs, US"LOG:", 4);
911 /* Show the selector that was passed into the call. */
913 for (i = 0; i < log_options_count; i++)
915 unsigned int bitnum = log_options[i].bit;
916 if (bitnum < BITWORDSIZE && selector == BIT(bitnum))
917 g = string_fmt_append(g, " %s", log_options[i].name);
920 g = string_fmt_append(g, "%s%s%s%s\n ",
921 flags & LOG_MAIN ? " MAIN" : "",
922 flags & LOG_PANIC ? " PANIC" : "",
923 (flags & LOG_PANIC_DIE) == LOG_PANIC_DIE ? " DIE" : "",
924 flags & LOG_REJECT ? " REJECT" : "");
926 if (flags & LOG_CONFIG) g = log_config_info(g, flags);
928 /* We want to be able to log tainted info, but log_buffer is directly
929 malloc'd. So use deliberately taint-nonchecking routines to build into
930 it, trusting that we will never expand the results. */
932 va_start(ap, format);
934 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
937 g = string_cat(g, US"**** log string overflowed log buffer ****");
941 g->size = LOG_BUFFER_SIZE;
942 g = string_catn(g, US"\n", 1);
943 debug_printf("%s", string_from_gstring(g));
945 gs.size = LOG_BUFFER_SIZE-1; /* Having used the buffer for debug output, */
946 gs.ptr = 0; /* reset it for the real use. */
949 /* If no log file is specified, we are in a mess. */
951 if (!(flags & (LOG_MAIN|LOG_PANIC|LOG_REJECT)))
952 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "log_write called with no log "
955 /* There are some weird circumstances in which logging is disabled. */
957 if (f.disable_logging)
959 DEBUG(D_any) debug_printf("log writing disabled\n");
960 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
964 /* Handle disabled reject log */
966 if (!write_rejectlog) flags &= ~LOG_REJECT;
968 /* Create the main message in the log buffer. Do not include the message id
969 when called by a utility. */
971 g = string_fmt_append(&gs, "%s ", tod_stamp(tod_log));
975 if (!syslog_pid) pid_position[0] = g->ptr; /* remember begin … */
976 g = string_fmt_append(g, "[%d] ", (int)getpid());
977 if (!syslog_pid) pid_position[1] = g->ptr; /* … and end+1 of the PID */
980 if (f.really_exim && message_id[0] != 0)
981 g = string_fmt_append(g, "%s ", message_id);
983 if (flags & LOG_CONFIG)
984 g = log_config_info(g, flags);
986 va_start(ap, format);
990 /* We want to be able to log tainted info, but log_buffer is directly
991 malloc'd. So use deliberately taint-nonchecking routines to build into
992 it, trusting that we will never expand the results. */
994 if (!string_vformat(g, SVFMT_TAINT_NOCHK, format, ap))
997 g = string_cat(g, US"**** log string overflowed log buffer ****\n");
1002 /* Add the raw, unrewritten, sender to the message if required. This is done
1003 this way because it kind of fits with LOG_RECIPIENTS. */
1005 if ( flags & LOG_SENDER
1006 && g->ptr < LOG_BUFFER_SIZE - 10 - Ustrlen(raw_sender))
1007 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " from <%s>", raw_sender);
1009 /* Add list of recipients to the message if required; the raw list,
1010 before rewriting, was saved in raw_recipients. There may be none, if an ACL
1011 discarded them all. */
1013 if ( flags & LOG_RECIPIENTS
1014 && g->ptr < LOG_BUFFER_SIZE - 6
1015 && raw_recipients_count > 0)
1018 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " for", NULL);
1019 for (i = 0; i < raw_recipients_count; i++)
1021 uschar * s = raw_recipients[i];
1022 if (LOG_BUFFER_SIZE - g->ptr < Ustrlen(s) + 3) break;
1023 g = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " %s", s);
1027 g = string_catn(g, US"\n", 1);
1028 string_from_gstring(g);
1030 /* Handle loggable errors when running a utility, or when address testing.
1031 Write to log_stderr unless debugging (when it will already have been written),
1032 or unless there is no log_stderr (expn called from daemon, for example). */
1034 if (!f.really_exim || f.log_testing_mode)
1036 if ( !debug_selector
1038 && (selector == 0 || (selector & log_selector[0]) != 0)
1041 fprintf(log_stderr, "LOG: %s", CS(log_buffer + 20)); /* no timestamp */
1043 fprintf(log_stderr, "%s", CS log_buffer);
1045 if ((flags & LOG_PANIC_DIE) == LOG_PANIC_DIE) exim_exit(EXIT_FAILURE);
1049 /* Handle the main log. We know that either syslog or file logging (or both) is
1050 set up. A real file gets left open during reception or delivery once it has
1051 been opened, but we don't want to keep on writing to it for too long after it
1052 has been renamed. Therefore, do a stat() and see if the inode has changed, and
1055 if ( flags & LOG_MAIN
1056 && (!selector || selector & log_selector[0]))
1058 if ( logging_mode & LOG_MODE_SYSLOG
1059 && (syslog_duplication || !(flags & (LOG_REJECT|LOG_PANIC))))
1060 write_syslog(LOG_INFO, log_buffer);
1062 if (logging_mode & LOG_MODE_FILE)
1064 struct stat statbuf;
1066 /* Check for a change to the mainlog file name when datestamping is in
1067 operation. This happens at midnight, at which point we want to roll over
1068 the file. Closing it has the desired effect. */
1070 if (mainlog_datestamp)
1072 uschar *nowstamp = tod_stamp(string_datestamp_type);
1073 if (Ustrncmp (mainlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1075 (void)close(mainlogfd); /* Close the file */
1076 mainlogfd = -1; /* Clear the file descriptor */
1077 mainlog_inode = 0; /* Unset the inode */
1078 mainlog_datestamp = NULL; /* Clear the datestamp */
1082 /* Otherwise, we want to check whether the file has been renamed by a
1083 cycling script. This could be "if else", but for safety's sake, leave it as
1084 "if" so that renaming the log starts a new file even when datestamping is
1088 if (Ustat(mainlog_name, &statbuf) < 0 || statbuf.st_ino != mainlog_inode)
1091 /* If the log is closed, open it. Then write the line. */
1095 open_log(&mainlogfd, lt_main, NULL); /* No return on error */
1096 if (fstat(mainlogfd, &statbuf) >= 0) mainlog_inode = statbuf.st_ino;
1099 /* Failing to write to the log is disastrous */
1101 written_len = write_to_fd_buf(mainlogfd, g->s, g->ptr);
1102 if (written_len != g->ptr)
1104 log_write_failed(US"main log", g->ptr, written_len);
1105 /* That function does not return */
1110 /* Handle the log for rejected messages. This can be globally disabled, in
1111 which case the flags are altered above. If there are any header lines (i.e. if
1112 the rejection is happening after the DATA phase), log the recipients and the
1115 if (flags & LOG_REJECT)
1117 if (header_list && LOGGING(rejected_header))
1122 if (recipients_count > 0)
1124 /* List the sender */
1126 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1127 "Envelope-from: <%s>\n", sender_address);
1130 /* List up to 5 recipients */
1132 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1133 "Envelope-to: <%s>\n", recipients_list[0].address);
1136 for (i = 1; i < recipients_count && i < 5; i++)
1138 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1139 " <%s>\n", recipients_list[i].address);
1143 if (i < recipients_count)
1145 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK, " ...\n", NULL);
1150 /* A header with a NULL text is an unfilled in Received: header */
1152 for (header_line * h = header_list; h; h = h->next) if (h->text)
1154 g2 = string_fmt_append_f(g, SVFMT_TAINT_NOCHK,
1155 "%c %s", h->type, h->text);
1158 else /* Buffer is full; truncate */
1160 g->ptr -= 100; /* For message and separator */
1161 if (g->s[g->ptr-1] == '\n') g->ptr--;
1162 g = string_cat(g, US"\n*** truncated ***\n");
1168 /* Write to syslog or to a log file */
1170 if ( logging_mode & LOG_MODE_SYSLOG
1171 && (syslog_duplication || !(flags & LOG_PANIC)))
1172 write_syslog(LOG_NOTICE, string_from_gstring(g));
1174 /* Check for a change to the rejectlog file name when datestamping is in
1175 operation. This happens at midnight, at which point we want to roll over
1176 the file. Closing it has the desired effect. */
1178 if (logging_mode & LOG_MODE_FILE)
1180 struct stat statbuf;
1182 if (rejectlog_datestamp)
1184 uschar *nowstamp = tod_stamp(string_datestamp_type);
1185 if (Ustrncmp (rejectlog_datestamp, nowstamp, Ustrlen(nowstamp)) != 0)
1187 (void)close(rejectlogfd); /* Close the file */
1188 rejectlogfd = -1; /* Clear the file descriptor */
1189 rejectlog_inode = 0; /* Unset the inode */
1190 rejectlog_datestamp = NULL; /* Clear the datestamp */
1194 /* Otherwise, we want to check whether the file has been renamed by a
1195 cycling script. This could be "if else", but for safety's sake, leave it as
1196 "if" so that renaming the log starts a new file even when datestamping is
1199 if (rejectlogfd >= 0)
1200 if (Ustat(rejectlog_name, &statbuf) < 0 ||
1201 statbuf.st_ino != rejectlog_inode)
1203 (void)close(rejectlogfd);
1205 rejectlog_inode = 0;
1208 /* Open the file if necessary, and write the data */
1210 if (rejectlogfd < 0)
1212 open_log(&rejectlogfd, lt_reject, NULL); /* No return on error */
1213 if (fstat(rejectlogfd, &statbuf) >= 0) rejectlog_inode = statbuf.st_ino;
1216 written_len = write_to_fd_buf(rejectlogfd, g->s, g->ptr);
1217 if (written_len != g->ptr)
1219 log_write_failed(US"reject log", g->ptr, written_len);
1220 /* That function does not return */
1226 /* Handle the panic log, which is not kept open like the others. If it fails to
1227 open, there will be a recursive call to log_write(). We detect this above and
1228 attempt to write to the system log as a last-ditch try at telling somebody. In
1229 all cases except mua_wrapper, try to write to log_stderr. */
1231 if (flags & LOG_PANIC)
1233 if (log_stderr && log_stderr != debug_file && !mua_wrapper)
1234 fprintf(log_stderr, "%s", CS string_from_gstring(g));
1236 if (logging_mode & LOG_MODE_SYSLOG)
1237 write_syslog(LOG_ALERT, log_buffer);
1239 /* If this panic logging was caused by a failure to open the main log,
1240 the original log line is in panic_save_buffer. Make an attempt to write it. */
1242 if (logging_mode & LOG_MODE_FILE)
1244 panic_recurseflag = TRUE;
1245 open_log(&paniclogfd, lt_panic, NULL); /* Won't return on failure */
1246 panic_recurseflag = FALSE;
1248 if (panic_save_buffer)
1249 (void) write(paniclogfd, panic_save_buffer, Ustrlen(panic_save_buffer));
1251 written_len = write_to_fd_buf(paniclogfd, g->s, g->ptr);
1252 if (written_len != g->ptr)
1254 int save_errno = errno;
1255 write_syslog(LOG_CRIT, log_buffer);
1256 sprintf(CS log_buffer, "write failed on panic log: length=%d result=%d "
1257 "errno=%d (%s)", g->ptr, (int)written_len, save_errno, strerror(save_errno));
1258 write_syslog(LOG_CRIT, string_from_gstring(g));
1259 flags |= LOG_PANIC_DIE;
1262 (void)close(paniclogfd);
1265 /* Give up if the DIE flag is set */
1267 if ((flags & LOG_PANIC_DIE) != LOG_PANIC)
1268 die(NULL, US"Unexpected failure, please try later");
1274 /*************************************************
1275 * Close any open log files *
1276 *************************************************/
1282 { (void)close(mainlogfd); mainlogfd = -1; }
1283 if (rejectlogfd >= 0)
1284 { (void)close(rejectlogfd); rejectlogfd = -1; }
1286 syslog_open = FALSE;
1291 /*************************************************
1292 * Multi-bit set or clear *
1293 *************************************************/
1295 /* These functions take a list of bit indexes (terminated by -1) and
1296 clear or set the corresponding bits in the selector.
1299 selector address of the bit string
1300 selsize number of words in the bit string
1301 bits list of bits to set
1305 bits_clear(unsigned int *selector, size_t selsize, int *bits)
1307 for(; *bits != -1; ++bits)
1308 BIT_CLEAR(selector, selsize, *bits);
1312 bits_set(unsigned int *selector, size_t selsize, int *bits)
1314 for(; *bits != -1; ++bits)
1315 BIT_SET(selector, selsize, *bits);
1320 /*************************************************
1321 * Decode bit settings for log/debug *
1322 *************************************************/
1324 /* This function decodes a string containing bit settings in the form of +name
1325 and/or -name sequences, and sets/unsets bits in a bit string accordingly. It
1326 also recognizes a numeric setting of the form =<number>, but this is not
1327 intended for user use. It's an easy way for Exim to pass the debug settings
1328 when it is re-exec'ed.
1330 The option table is a list of names and bit indexes. The index -1
1331 means "set all bits, except for those listed in notall". The notall
1332 list is terminated by -1.
1334 The action taken for bad values varies depending upon why we're here.
1335 For log messages, or if the debugging is triggered from config, then we write
1336 to the log on the way out. For debug setting triggered from the command-line,
1337 we treat it as an unknown option: error message to stderr and die.
1340 selector address of the bit string
1341 selsize number of words in the bit string
1342 notall list of bits to exclude from "all"
1343 string the configured string
1344 options the table of option names
1346 which "log" or "debug"
1347 flags DEBUG_FROM_CONFIG
1349 Returns: nothing on success - bomb out on failure
1353 decode_bits(unsigned int *selector, size_t selsize, int *notall,
1354 uschar *string, bit_table *options, int count, uschar *which, int flags)
1357 if (!string) return;
1361 char *end; /* Not uschar */
1362 memset(selector, 0, sizeof(*selector)*selsize);
1363 *selector = strtoul(CS string+1, &end, 0);
1365 errmsg = string_sprintf("malformed numeric %s_selector setting: %s", which,
1370 /* Handle symbolic setting */
1377 bit_table *start, *end;
1379 Uskip_whitespace(&string);
1380 if (!*string) return;
1382 if (*string != '+' && *string != '-')
1384 errmsg = string_sprintf("malformed %s_selector setting: "
1385 "+ or - expected but found \"%s\"", which, string);
1389 adding = *string++ == '+';
1391 while (isalnum(*string) || *string == '_') string++;
1395 end = options + count;
1399 bit_table *middle = start + (end - start)/2;
1400 int c = Ustrncmp(s, middle->name, len);
1402 if (middle->name[len] != 0) c = -1; else
1404 unsigned int bit = middle->bit;
1410 memset(selector, -1, sizeof(*selector)*selsize);
1411 bits_clear(selector, selsize, notall);
1414 memset(selector, 0, sizeof(*selector)*selsize);
1417 BIT_SET(selector, selsize, bit);
1419 BIT_CLEAR(selector, selsize, bit);
1421 break; /* Out of loop to match selector name */
1423 if (c < 0) end = middle; else start = middle + 1;
1424 } /* Loop to match selector name */
1428 errmsg = string_sprintf("unknown %s_selector setting: %c%.*s", which,
1429 adding? '+' : '-', len, s);
1432 } /* Loop for selector names */
1434 /* Handle disasters */
1437 if (Ustrcmp(which, "debug") == 0)
1439 if (flags & DEBUG_FROM_CONFIG)
1441 log_write(0, LOG_CONFIG|LOG_PANIC, "%s", errmsg);
1444 fprintf(stderr, "exim: %s\n", errmsg);
1447 else log_write(0, LOG_CONFIG|LOG_PANIC_DIE, "%s", errmsg);
1452 /*************************************************
1453 * Activate a debug logfile (late) *
1454 *************************************************/
1456 /* Normally, debugging is activated from the command-line; it may be useful
1457 within the configuration to activate debugging later, based on certain
1458 conditions. If debugging is already in progress, we return early, no action
1459 taken (besides debug-logging that we wanted debug-logging).
1461 Failures in options are not fatal but will result in paniclog entries for the
1464 The first use of this is in ACL logic, "control = debug/tag=foo/opts=+expand"
1465 which can be combined with conditions, etc, to activate extra logging only
1466 for certain sources. The second use is inetd wait mode debug preservation. */
1469 debug_logging_activate(uschar *tag_name, uschar *opts)
1475 debug_printf("DEBUGGING ACTIVATED FROM WITHIN CONFIG.\n"
1476 "DEBUG: Tag=\"%s\" opts=\"%s\"\n", tag_name, opts ? opts : US"");
1480 if (tag_name != NULL && (Ustrchr(tag_name, '/') != NULL))
1482 log_write(0, LOG_MAIN|LOG_PANIC, "debug tag may not contain a '/' in: %s",
1487 debug_selector = D_default;
1489 decode_bits(&debug_selector, 1, debug_notall, opts,
1490 debug_options, debug_options_count, US"debug", DEBUG_FROM_CONFIG);
1492 /* When activating from a transport process we may never have logged at all
1493 resulting in certain setup not having been done. Hack this for now so we
1494 do not segfault; note that nondefault log locations will not work */
1496 if (!*file_path) set_file_path();
1498 open_log(&fd, lt_debug, tag_name);
1501 debug_file = fdopen(fd, "w");
1503 log_write(0, LOG_MAIN|LOG_PANIC, "unable to open debug log");
1508 debug_logging_stop(void)
1510 if (!debug_file || !debuglog_name[0]) return;
1515 unlink_log(lt_debug);