2 * utils.c - various utility functions used in pppd.
4 * Copyright (c) 1999-2002 Paul Mackerras. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. The name(s) of the authors of this software must not be used to
14 * endorse or promote products derived from this software without
15 * prior written permission.
17 * 3. Redistributions of any form whatsoever must retain the following
19 * "This product includes software developed by Paul Mackerras
20 * <paulus@samba.org>".
22 * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
23 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
24 * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
25 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
26 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
27 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
28 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
45 #include <sys/param.h>
46 #include <sys/types.h>
49 #include <sys/resource.h>
51 #include <sys/socket.h>
52 #include <netinet/in.h>
54 #include <sys/mkdev.h>
63 extern char *strerror();
66 static void logit(int, char *, va_list);
67 static void log_write(int, char *);
68 static void vslp_printer(void *, char *, ...);
69 static void format_packet(u_char *, int, printer_func, void *);
77 * strlcpy - like strcpy/strncpy, doesn't overflow destination buffer,
78 * always leaves destination null-terminated (for len > 0).
81 strlcpy(char *dest, const char *src, size_t len)
83 size_t ret = strlen(src);
89 strncpy(dest, src, len - 1);
97 * strlcat - like strcat/strncat, doesn't overflow destination buffer,
98 * always leaves destination null-terminated (for len > 0).
101 strlcat(char *dest, const char *src, size_t len)
103 size_t dlen = strlen(dest);
105 return dlen + strlcpy(dest + dlen, src, (len > dlen? len - dlen: 0));
110 * slprintf - format a message into a buffer. Like sprintf except we
111 * also specify the length of the output buffer, and we handle
112 * %m (error message), %v (visible string),
113 * %q (quoted string), %t (current time) and %I (IP address) formats.
114 * Doesn't do floating-point formats.
115 * Returns the number of chars put into buf.
118 slprintf(char *buf, int buflen, char *fmt, ...)
124 n = vslprintf(buf, buflen, fmt, args);
130 * vslprintf - like slprintf, takes a va_list instead of a list of args.
132 #define OUTCHAR(c) (buflen > 0? (--buflen, *buf++ = (c)): 0)
135 vslprintf(char *buf, int buflen, char *fmt, va_list args)
138 int width, prec, fillch;
139 int base, len, neg, quoted;
141 unsigned long val = 0;
142 char *str, *f, *buf0;
147 static char hexchars[] = "0123456789abcdef";
148 struct buffer_info bufinfo;
154 for (f = fmt; *f != '%' && *f != 0; ++f)
160 memcpy(buf, fmt, len);
176 width = va_arg(args, int);
180 width = width * 10 + c - '0';
187 prec = va_arg(args, int);
192 prec = prec * 10 + c - '0';
206 lval = va_arg(args, long);
215 val = va_arg(args, unsigned long);
221 --fmt; /* so %lz outputs %lz etc. */
226 i = va_arg(args, int);
235 val = va_arg(args, unsigned int);
239 val = va_arg(args, unsigned int);
244 val = va_arg(args, unsigned int);
248 val = (unsigned long) va_arg(args, void *);
253 str = va_arg(args, char *);
256 num[0] = va_arg(args, int);
261 str = strerror(errno);
264 ip = va_arg(args, u_int32_t);
266 slprintf(num, sizeof(num), "%d.%d.%d.%d", (ip >> 24) & 0xff,
267 (ip >> 16) & 0xff, (ip >> 8) & 0xff, ip & 0xff);
273 str += 4; /* chop off the day name */
274 str[15] = 0; /* chop off year and newline */
276 case 'v': /* "visible" string */
277 case 'q': /* quoted string */
279 p = va_arg(args, unsigned char *);
281 p = (unsigned char *)"<NULL>";
282 if (fillch == '0' && prec >= 0) {
284 termch = -1; /* matches no unsigned char value */
287 if (prec != -1 && n > prec)
289 termch = 0; /* stop on null byte */
291 while (n > 0 && buflen > 0) {
296 if (!quoted && c >= 0x80) {
301 if (quoted && (c == '"' || c == '\\'))
303 if (c < 0x20 || (0x7f <= c && c < 0xa0)) {
307 case '\t': OUTCHAR('t'); break;
308 case '\n': OUTCHAR('n'); break;
309 case '\b': OUTCHAR('b'); break;
310 case '\f': OUTCHAR('f'); break;
313 OUTCHAR(hexchars[c >> 4]);
314 OUTCHAR(hexchars[c & 0xf]);
328 case 'P': /* print PPP packet */
330 bufinfo.len = buflen + 1;
331 p = va_arg(args, unsigned char *);
332 n = va_arg(args, int);
333 format_packet(p, n, vslp_printer, &bufinfo);
335 buflen = bufinfo.len - 1;
338 p = va_arg(args, unsigned char *);
339 for (n = prec; n > 0; --n) {
343 OUTCHAR(hexchars[(c >> 4) & 0xf]);
344 OUTCHAR(hexchars[c & 0xf]);
350 --fmt; /* so %z outputs %z etc. */
355 str = num + sizeof(num);
357 while (str > num + neg) {
358 *--str = hexchars[val % base];
360 if (--prec <= 0 && val == 0)
372 len = num + sizeof(num) - 1 - str;
374 for (len = 0; len < buflen && (prec == -1 || len < prec); ++len)
381 if ((n = width - len) > 0) {
389 memcpy(buf, str, len);
398 * vslp_printer - used in processing a %P format
401 vslp_printer(void *arg, char *fmt, ...)
405 struct buffer_info *bi;
409 bi = (struct buffer_info *) arg;
410 n = vslprintf(bi->ptr, bi->len, fmt, pvar);
419 * log_packet - format a packet and log it.
423 log_packet(u_char *p, int len, char *prefix, int level)
425 init_pr_log(prefix, level);
426 format_packet(p, len, pr_log, &level);
432 * format_packet - make a readable representation of a packet,
433 * calling `printer(arg, format, ...)' to output it.
436 format_packet(u_char *p, int len, printer_func printer, void *arg)
440 struct protent *protp;
442 if (len >= PPP_HDRLEN && p[0] == PPP_ALLSTATIONS && p[1] == PPP_UI) {
446 for (i = 0; (protp = protocols[i]) != NULL; ++i)
447 if (proto == protp->protocol)
450 printer(arg, "[%s", protp->name);
451 n = (*protp->printpkt)(p, len, printer, arg);
456 for (i = 0; (protp = protocols[i]) != NULL; ++i)
457 if (proto == (protp->protocol & ~0x8000))
459 if (protp != 0 && protp->data_name != 0) {
460 printer(arg, "[%s data]", protp->data_name);
462 printer(arg, "%.8B ...", p);
464 printer(arg, "%.*B", len, p);
467 printer(arg, "[proto=0x%x]", proto);
472 printer(arg, "%.32B ...", p);
474 printer(arg, "%.*B", len, p);
478 * init_pr_log, end_pr_log - initialize and finish use of pr_log.
481 static char line[256]; /* line to be logged accumulated here */
482 static char *linep; /* current pointer within line */
483 static int llevel; /* level for logging */
486 init_pr_log(const char *prefix, int level)
489 if (prefix != NULL) {
490 strlcpy(line, prefix, sizeof(line));
491 linep = line + strlen(line);
501 log_write(llevel, line);
506 * pr_log - printer routine for outputting to syslog
509 pr_log(void *arg, char *fmt, ...)
518 n = vslprintf(buf, sizeof(buf), fmt, pvar);
522 eol = strchr(buf, '\n');
524 l = (eol == NULL)? n: eol - buf;
525 if (linep + l < line + sizeof(line)) {
527 memcpy(linep, buf, l);
533 eol = strchr(p, '\n');
536 log_write(llevel, line);
540 while (eol != NULL) {
542 log_write(llevel, p);
544 eol = strchr(p, '\n');
547 /* assumes sizeof(buf) <= sizeof(line) */
556 * print_string - print a readable representation of a string using
560 print_string(char *p, int len, printer_func printer, void *arg)
565 for (; len > 0; --len) {
567 if (' ' <= c && c <= '~') {
568 if (c == '\\' || c == '"')
570 printer(arg, "%c", c);
583 printer(arg, "\\%.3o", (unsigned char) c);
591 * logit - does the hard work for fatal et al.
594 logit(int level, char *fmt, va_list args)
598 vslprintf(buf, sizeof(buf), fmt, args);
599 log_write(level, buf);
603 log_write(int level, char *buf)
605 syslog(level, "%s", buf);
606 if (log_to_fd >= 0 && (level != LOG_DEBUG || debug)) {
609 if (n > 0 && buf[n-1] == '\n')
611 if (write(log_to_fd, buf, n) != n
612 || write(log_to_fd, "\n", 1) != 1)
618 * fatal - log an error message and die horribly.
621 fatal(char *fmt, ...)
627 logit(LOG_ERR, fmt, pvar);
630 die(1); /* as promised */
634 * error - log an error message.
637 error(char *fmt, ...)
643 logit(LOG_ERR, fmt, pvar);
649 * warn - log a warning message.
658 logit(LOG_WARNING, fmt, pvar);
663 * notice - log a notice-level message.
666 notice(char *fmt, ...)
672 logit(LOG_NOTICE, fmt, pvar);
677 * info - log an informational message.
686 logit(LOG_INFO, fmt, pvar);
691 * dbglog - log a debug message.
694 dbglog(char *fmt, ...)
700 logit(LOG_DEBUG, fmt, pvar);
705 * dump_packet - print out a packet in readable form if it is interesting.
706 * Assumes len >= PPP_HDRLEN.
709 dump_packet(const char *tag, unsigned char *p, int len)
717 * don't print LCP echo request/reply packets if debug <= 1
718 * and the link is up.
720 proto = (p[2] << 8) + p[3];
721 if (debug <= 1 && unsuccess == 0 && proto == PPP_LCP
722 && len >= PPP_HDRLEN + HEADERLEN) {
723 unsigned char *lcp = p + PPP_HDRLEN;
724 int l = (lcp[2] << 8) + lcp[3];
726 if ((lcp[0] == ECHOREQ || lcp[0] == ECHOREP)
727 && l >= HEADERLEN && l <= len - PPP_HDRLEN)
731 dbglog("%s %P", tag, p, len);
735 * complete_read - read a full `count' bytes from fd,
736 * unless end-of-file or an error other than EINTR is encountered.
739 complete_read(int fd, void *buf, size_t count)
745 for (done = 0; done < count; ) {
746 nb = read(fd, ptr, count - done);
748 if (errno == EINTR && !got_sigterm)
760 /* Procedures for locking the serial device using a lock file. */
763 #define LOCK_DIR "/var/lock"
766 #define LOCK_DIR "/var/spool/locks"
768 #define LOCK_DIR "/var/spool/lock"
771 #endif /* LOCK_DIR */
773 static char lock_file[MAXPATHLEN];
776 * lock - create a lock file for the named device
784 result = mklock (dev, (void *) 0);
786 strlcpy(lock_file, dev, sizeof(lock_file));
791 notice("Device %s is locked by pid %d", dev, result);
793 error("Can't create lock file %s", lock_file);
798 char lock_buffer[12];
804 if (stat(dev, &sbuf) < 0) {
805 error("Can't get device number for %s: %m", dev);
808 if ((sbuf.st_mode & S_IFMT) != S_IFCHR) {
809 error("Can't lock %s: not a character device", dev);
812 slprintf(lock_file, sizeof(lock_file), "%s/LK.%03d.%03d.%03d",
813 LOCK_DIR, major(sbuf.st_dev),
814 major(sbuf.st_rdev), minor(sbuf.st_rdev));
817 char lockdev[MAXPATHLEN];
819 if ((p = strstr(dev, "dev/")) != NULL) {
821 strncpy(lockdev, dev, MAXPATHLEN-1);
822 lockdev[MAXPATHLEN-1] = 0;
823 while ((p = strrchr(lockdev, '/')) != NULL) {
828 if ((p = strrchr(dev, '/')) != NULL)
831 slprintf(lock_file, sizeof(lock_file), "%s/LCK..%s", LOCK_DIR, dev);
834 while ((fd = open(lock_file, O_EXCL | O_CREAT | O_RDWR, 0644)) < 0) {
835 if (errno != EEXIST) {
836 error("Can't create lock file %s: %m", lock_file);
840 /* Read the lock file to find out who has the device locked. */
841 fd = open(lock_file, O_RDONLY, 0);
843 if (errno == ENOENT) /* This is just a timing problem. */
845 error("Can't open existing lock file %s: %m", lock_file);
849 n = read(fd, lock_buffer, 11);
851 n = read(fd, &pid, sizeof(pid));
852 #endif /* LOCK_BINARY */
856 error("Can't read pid from lock file %s", lock_file);
860 /* See if the process still exists. */
863 pid = atoi(lock_buffer);
864 #endif /* LOCK_BINARY */
866 return 1; /* somebody else locked it for us */
868 || (kill(pid, 0) == -1 && errno == ESRCH)) {
869 if (unlink (lock_file) == 0) {
870 notice("Removed stale lock on %s (pid %d)", dev, pid);
873 warn("Couldn't remove stale lock on %s", dev);
875 notice("Device %s is locked by pid %d", dev, pid);
886 slprintf(lock_buffer, sizeof(lock_buffer), "%10d\n", pid);
887 write (fd, lock_buffer, 11);
889 write(fd, &pid, sizeof (pid));
898 * relock - called to update our lockfile when we are about to detach,
899 * thus changing our pid (we fork, the child carries on, and the parent dies).
900 * Note that this is called by the parent, with pid equal to the pid
901 * of the child. This avoids a potential race which would exist if
902 * we had the child rewrite the lockfile (the parent might die first,
903 * and another process could think the lock was stale if it checked
904 * between when the parent died and the child rewrote the lockfile).
910 /* XXX is there a way to do this? */
915 char lock_buffer[12];
917 if (lock_file[0] == 0)
919 fd = open(lock_file, O_WRONLY, 0);
921 error("Couldn't reopen lock file %s: %m", lock_file);
927 slprintf(lock_buffer, sizeof(lock_buffer), "%10d\n", pid);
928 write (fd, lock_buffer, 11);
930 write(fd, &pid, sizeof(pid));
931 #endif /* LOCK_BINARY */
939 * unlock - remove our lockfile
946 (void) rmlock(lock_file, (void *) 0);