- (djm) Add openssh.xml to .cvsignore and sort it
[openssh-git.git] / misc.c
blob78bca2faefa77c782b7968ccaa67b771c7cbdd3f
1 /* $OpenBSD: misc.c,v 1.64 2006/08/03 03:34:42 deraadt Exp $ */
2 /*
3 * Copyright (c) 2000 Markus Friedl. All rights reserved.
4 * Copyright (c) 2005,2006 Damien Miller. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 #include "includes.h"
29 #include <sys/types.h>
30 #include <sys/ioctl.h>
31 #include <sys/socket.h>
32 #include <sys/param.h>
34 #include <stdarg.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <unistd.h>
40 #include <netinet/in.h>
41 #include <netinet/tcp.h>
43 #include <errno.h>
44 #include <fcntl.h>
45 #ifdef HAVE_PATHS_H
46 # include <paths.h>
47 #include <pwd.h>
48 #endif
49 #ifdef SSH_TUN_OPENBSD
50 #include <net/if.h>
51 #endif
53 #include "xmalloc.h"
54 #include "misc.h"
55 #include "log.h"
56 #include "ssh.h"
58 /* remove newline at end of string */
59 char *
60 chop(char *s)
62 char *t = s;
63 while (*t) {
64 if (*t == '\n' || *t == '\r') {
65 *t = '\0';
66 return s;
68 t++;
70 return s;
74 /* set/unset filedescriptor to non-blocking */
75 int
76 set_nonblock(int fd)
78 int val;
80 val = fcntl(fd, F_GETFL, 0);
81 if (val < 0) {
82 error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
83 return (-1);
85 if (val & O_NONBLOCK) {
86 debug3("fd %d is O_NONBLOCK", fd);
87 return (0);
89 debug2("fd %d setting O_NONBLOCK", fd);
90 val |= O_NONBLOCK;
91 if (fcntl(fd, F_SETFL, val) == -1) {
92 debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
93 strerror(errno));
94 return (-1);
96 return (0);
99 int
100 unset_nonblock(int fd)
102 int val;
104 val = fcntl(fd, F_GETFL, 0);
105 if (val < 0) {
106 error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno));
107 return (-1);
109 if (!(val & O_NONBLOCK)) {
110 debug3("fd %d is not O_NONBLOCK", fd);
111 return (0);
113 debug("fd %d clearing O_NONBLOCK", fd);
114 val &= ~O_NONBLOCK;
115 if (fcntl(fd, F_SETFL, val) == -1) {
116 debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
117 fd, strerror(errno));
118 return (-1);
120 return (0);
123 /* disable nagle on socket */
124 void
125 set_nodelay(int fd)
127 int opt;
128 socklen_t optlen;
130 optlen = sizeof opt;
131 if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
132 debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
133 return;
135 if (opt == 1) {
136 debug2("fd %d is TCP_NODELAY", fd);
137 return;
139 opt = 1;
140 debug2("fd %d setting TCP_NODELAY", fd);
141 if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
142 error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
145 /* Characters considered whitespace in strsep calls. */
146 #define WHITESPACE " \t\r\n"
147 #define QUOTE "\""
149 /* return next token in configuration line */
150 char *
151 strdelim(char **s)
153 char *old;
154 int wspace = 0;
156 if (*s == NULL)
157 return NULL;
159 old = *s;
161 *s = strpbrk(*s, WHITESPACE QUOTE "=");
162 if (*s == NULL)
163 return (old);
165 if (*s[0] == '\"') {
166 memmove(*s, *s + 1, strlen(*s)); /* move nul too */
167 /* Find matching quote */
168 if ((*s = strpbrk(*s, QUOTE)) == NULL) {
169 return (NULL); /* no matching quote */
170 } else {
171 *s[0] = '\0';
172 return (old);
176 /* Allow only one '=' to be skipped */
177 if (*s[0] == '=')
178 wspace = 1;
179 *s[0] = '\0';
181 /* Skip any extra whitespace after first token */
182 *s += strspn(*s + 1, WHITESPACE) + 1;
183 if (*s[0] == '=' && !wspace)
184 *s += strspn(*s + 1, WHITESPACE) + 1;
186 return (old);
189 struct passwd *
190 pwcopy(struct passwd *pw)
192 struct passwd *copy = xcalloc(1, sizeof(*copy));
194 copy->pw_name = xstrdup(pw->pw_name);
195 copy->pw_passwd = xstrdup(pw->pw_passwd);
196 copy->pw_gecos = xstrdup(pw->pw_gecos);
197 copy->pw_uid = pw->pw_uid;
198 copy->pw_gid = pw->pw_gid;
199 #ifdef HAVE_PW_EXPIRE_IN_PASSWD
200 copy->pw_expire = pw->pw_expire;
201 #endif
202 #ifdef HAVE_PW_CHANGE_IN_PASSWD
203 copy->pw_change = pw->pw_change;
204 #endif
205 #ifdef HAVE_PW_CLASS_IN_PASSWD
206 copy->pw_class = xstrdup(pw->pw_class);
207 #endif
208 copy->pw_dir = xstrdup(pw->pw_dir);
209 copy->pw_shell = xstrdup(pw->pw_shell);
210 return copy;
214 * Convert ASCII string to TCP/IP port number.
215 * Port must be >0 and <=65535.
216 * Return 0 if invalid.
219 a2port(const char *s)
221 long port;
222 char *endp;
224 errno = 0;
225 port = strtol(s, &endp, 0);
226 if (s == endp || *endp != '\0' ||
227 (errno == ERANGE && (port == LONG_MIN || port == LONG_MAX)) ||
228 port <= 0 || port > 65535)
229 return 0;
231 return port;
235 a2tun(const char *s, int *remote)
237 const char *errstr = NULL;
238 char *sp, *ep;
239 int tun;
241 if (remote != NULL) {
242 *remote = SSH_TUNID_ANY;
243 sp = xstrdup(s);
244 if ((ep = strchr(sp, ':')) == NULL) {
245 xfree(sp);
246 return (a2tun(s, NULL));
248 ep[0] = '\0'; ep++;
249 *remote = a2tun(ep, NULL);
250 tun = a2tun(sp, NULL);
251 xfree(sp);
252 return (*remote == SSH_TUNID_ERR ? *remote : tun);
255 if (strcasecmp(s, "any") == 0)
256 return (SSH_TUNID_ANY);
258 tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
259 if (errstr != NULL)
260 return (SSH_TUNID_ERR);
262 return (tun);
265 #define SECONDS 1
266 #define MINUTES (SECONDS * 60)
267 #define HOURS (MINUTES * 60)
268 #define DAYS (HOURS * 24)
269 #define WEEKS (DAYS * 7)
272 * Convert a time string into seconds; format is
273 * a sequence of:
274 * time[qualifier]
276 * Valid time qualifiers are:
277 * <none> seconds
278 * s|S seconds
279 * m|M minutes
280 * h|H hours
281 * d|D days
282 * w|W weeks
284 * Examples:
285 * 90m 90 minutes
286 * 1h30m 90 minutes
287 * 2d 2 days
288 * 1w 1 week
290 * Return -1 if time string is invalid.
292 long
293 convtime(const char *s)
295 long total, secs;
296 const char *p;
297 char *endp;
299 errno = 0;
300 total = 0;
301 p = s;
303 if (p == NULL || *p == '\0')
304 return -1;
306 while (*p) {
307 secs = strtol(p, &endp, 10);
308 if (p == endp ||
309 (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) ||
310 secs < 0)
311 return -1;
313 switch (*endp++) {
314 case '\0':
315 endp--;
316 break;
317 case 's':
318 case 'S':
319 break;
320 case 'm':
321 case 'M':
322 secs *= MINUTES;
323 break;
324 case 'h':
325 case 'H':
326 secs *= HOURS;
327 break;
328 case 'd':
329 case 'D':
330 secs *= DAYS;
331 break;
332 case 'w':
333 case 'W':
334 secs *= WEEKS;
335 break;
336 default:
337 return -1;
339 total += secs;
340 if (total < 0)
341 return -1;
342 p = endp;
345 return total;
349 * Returns a standardized host+port identifier string.
350 * Caller must free returned string.
352 char *
353 put_host_port(const char *host, u_short port)
355 char *hoststr;
357 if (port == 0 || port == SSH_DEFAULT_PORT)
358 return(xstrdup(host));
359 if (asprintf(&hoststr, "[%s]:%d", host, (int)port) < 0)
360 fatal("put_host_port: asprintf: %s", strerror(errno));
361 debug3("put_host_port: %s", hoststr);
362 return hoststr;
366 * Search for next delimiter between hostnames/addresses and ports.
367 * Argument may be modified (for termination).
368 * Returns *cp if parsing succeeds.
369 * *cp is set to the start of the next delimiter, if one was found.
370 * If this is the last field, *cp is set to NULL.
372 char *
373 hpdelim(char **cp)
375 char *s, *old;
377 if (cp == NULL || *cp == NULL)
378 return NULL;
380 old = s = *cp;
381 if (*s == '[') {
382 if ((s = strchr(s, ']')) == NULL)
383 return NULL;
384 else
385 s++;
386 } else if ((s = strpbrk(s, ":/")) == NULL)
387 s = *cp + strlen(*cp); /* skip to end (see first case below) */
389 switch (*s) {
390 case '\0':
391 *cp = NULL; /* no more fields*/
392 break;
394 case ':':
395 case '/':
396 *s = '\0'; /* terminate */
397 *cp = s + 1;
398 break;
400 default:
401 return NULL;
404 return old;
407 char *
408 cleanhostname(char *host)
410 if (*host == '[' && host[strlen(host) - 1] == ']') {
411 host[strlen(host) - 1] = '\0';
412 return (host + 1);
413 } else
414 return host;
417 char *
418 colon(char *cp)
420 int flag = 0;
422 if (*cp == ':') /* Leading colon is part of file name. */
423 return (0);
424 if (*cp == '[')
425 flag = 1;
427 for (; *cp; ++cp) {
428 if (*cp == '@' && *(cp+1) == '[')
429 flag = 1;
430 if (*cp == ']' && *(cp+1) == ':' && flag)
431 return (cp+1);
432 if (*cp == ':' && !flag)
433 return (cp);
434 if (*cp == '/')
435 return (0);
437 return (0);
440 /* function to assist building execv() arguments */
441 void
442 addargs(arglist *args, char *fmt, ...)
444 va_list ap;
445 char *cp;
446 u_int nalloc;
447 int r;
449 va_start(ap, fmt);
450 r = vasprintf(&cp, fmt, ap);
451 va_end(ap);
452 if (r == -1)
453 fatal("addargs: argument too long");
455 nalloc = args->nalloc;
456 if (args->list == NULL) {
457 nalloc = 32;
458 args->num = 0;
459 } else if (args->num+2 >= nalloc)
460 nalloc *= 2;
462 args->list = xrealloc(args->list, nalloc, sizeof(char *));
463 args->nalloc = nalloc;
464 args->list[args->num++] = cp;
465 args->list[args->num] = NULL;
468 void
469 replacearg(arglist *args, u_int which, char *fmt, ...)
471 va_list ap;
472 char *cp;
473 int r;
475 va_start(ap, fmt);
476 r = vasprintf(&cp, fmt, ap);
477 va_end(ap);
478 if (r == -1)
479 fatal("replacearg: argument too long");
481 if (which >= args->num)
482 fatal("replacearg: tried to replace invalid arg %d >= %d",
483 which, args->num);
484 xfree(args->list[which]);
485 args->list[which] = cp;
488 void
489 freeargs(arglist *args)
491 u_int i;
493 if (args->list != NULL) {
494 for (i = 0; i < args->num; i++)
495 xfree(args->list[i]);
496 xfree(args->list);
497 args->nalloc = args->num = 0;
498 args->list = NULL;
503 * Expands tildes in the file name. Returns data allocated by xmalloc.
504 * Warning: this calls getpw*.
506 char *
507 tilde_expand_filename(const char *filename, uid_t uid)
509 const char *path;
510 char user[128], ret[MAXPATHLEN];
511 struct passwd *pw;
512 u_int len, slash;
514 if (*filename != '~')
515 return (xstrdup(filename));
516 filename++;
518 path = strchr(filename, '/');
519 if (path != NULL && path > filename) { /* ~user/path */
520 slash = path - filename;
521 if (slash > sizeof(user) - 1)
522 fatal("tilde_expand_filename: ~username too long");
523 memcpy(user, filename, slash);
524 user[slash] = '\0';
525 if ((pw = getpwnam(user)) == NULL)
526 fatal("tilde_expand_filename: No such user %s", user);
527 } else if ((pw = getpwuid(uid)) == NULL) /* ~/path */
528 fatal("tilde_expand_filename: No such uid %d", uid);
530 if (strlcpy(ret, pw->pw_dir, sizeof(ret)) >= sizeof(ret))
531 fatal("tilde_expand_filename: Path too long");
533 /* Make sure directory has a trailing '/' */
534 len = strlen(pw->pw_dir);
535 if ((len == 0 || pw->pw_dir[len - 1] != '/') &&
536 strlcat(ret, "/", sizeof(ret)) >= sizeof(ret))
537 fatal("tilde_expand_filename: Path too long");
539 /* Skip leading '/' from specified path */
540 if (path != NULL)
541 filename = path + 1;
542 if (strlcat(ret, filename, sizeof(ret)) >= sizeof(ret))
543 fatal("tilde_expand_filename: Path too long");
545 return (xstrdup(ret));
549 * Expand a string with a set of %[char] escapes. A number of escapes may be
550 * specified as (char *escape_chars, char *replacement) pairs. The list must
551 * be terminated by a NULL escape_char. Returns replaced string in memory
552 * allocated by xmalloc.
554 char *
555 percent_expand(const char *string, ...)
557 #define EXPAND_MAX_KEYS 16
558 struct {
559 const char *key;
560 const char *repl;
561 } keys[EXPAND_MAX_KEYS];
562 u_int num_keys, i, j;
563 char buf[4096];
564 va_list ap;
566 /* Gather keys */
567 va_start(ap, string);
568 for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
569 keys[num_keys].key = va_arg(ap, char *);
570 if (keys[num_keys].key == NULL)
571 break;
572 keys[num_keys].repl = va_arg(ap, char *);
573 if (keys[num_keys].repl == NULL)
574 fatal("percent_expand: NULL replacement");
576 va_end(ap);
578 if (num_keys >= EXPAND_MAX_KEYS)
579 fatal("percent_expand: too many keys");
581 /* Expand string */
582 *buf = '\0';
583 for (i = 0; *string != '\0'; string++) {
584 if (*string != '%') {
585 append:
586 buf[i++] = *string;
587 if (i >= sizeof(buf))
588 fatal("percent_expand: string too long");
589 buf[i] = '\0';
590 continue;
592 string++;
593 if (*string == '%')
594 goto append;
595 for (j = 0; j < num_keys; j++) {
596 if (strchr(keys[j].key, *string) != NULL) {
597 i = strlcat(buf, keys[j].repl, sizeof(buf));
598 if (i >= sizeof(buf))
599 fatal("percent_expand: string too long");
600 break;
603 if (j >= num_keys)
604 fatal("percent_expand: unknown key %%%c", *string);
606 return (xstrdup(buf));
607 #undef EXPAND_MAX_KEYS
611 * Read an entire line from a public key file into a static buffer, discarding
612 * lines that exceed the buffer size. Returns 0 on success, -1 on failure.
615 read_keyfile_line(FILE *f, const char *filename, char *buf, size_t bufsz,
616 u_long *lineno)
618 while (fgets(buf, bufsz, f) != NULL) {
619 (*lineno)++;
620 if (buf[strlen(buf) - 1] == '\n' || feof(f)) {
621 return 0;
622 } else {
623 debug("%s: %s line %lu exceeds size limit", __func__,
624 filename, *lineno);
625 /* discard remainder of line */
626 while (fgetc(f) != '\n' && !feof(f))
627 ; /* nothing */
630 return -1;
634 tun_open(int tun, int mode)
636 #if defined(CUSTOM_SYS_TUN_OPEN)
637 return (sys_tun_open(tun, mode));
638 #elif defined(SSH_TUN_OPENBSD)
639 struct ifreq ifr;
640 char name[100];
641 int fd = -1, sock;
643 /* Open the tunnel device */
644 if (tun <= SSH_TUNID_MAX) {
645 snprintf(name, sizeof(name), "/dev/tun%d", tun);
646 fd = open(name, O_RDWR);
647 } else if (tun == SSH_TUNID_ANY) {
648 for (tun = 100; tun >= 0; tun--) {
649 snprintf(name, sizeof(name), "/dev/tun%d", tun);
650 if ((fd = open(name, O_RDWR)) >= 0)
651 break;
653 } else {
654 debug("%s: invalid tunnel %u", __func__, tun);
655 return (-1);
658 if (fd < 0) {
659 debug("%s: %s open failed: %s", __func__, name, strerror(errno));
660 return (-1);
663 debug("%s: %s mode %d fd %d", __func__, name, mode, fd);
665 /* Set the tunnel device operation mode */
666 snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "tun%d", tun);
667 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
668 goto failed;
670 if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1)
671 goto failed;
673 /* Set interface mode */
674 ifr.ifr_flags &= ~IFF_UP;
675 if (mode == SSH_TUNMODE_ETHERNET)
676 ifr.ifr_flags |= IFF_LINK0;
677 else
678 ifr.ifr_flags &= ~IFF_LINK0;
679 if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
680 goto failed;
682 /* Bring interface up */
683 ifr.ifr_flags |= IFF_UP;
684 if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1)
685 goto failed;
687 close(sock);
688 return (fd);
690 failed:
691 if (fd >= 0)
692 close(fd);
693 if (sock >= 0)
694 close(sock);
695 debug("%s: failed to set %s mode %d: %s", __func__, name,
696 mode, strerror(errno));
697 return (-1);
698 #else
699 error("Tunnel interfaces are not supported on this platform");
700 return (-1);
701 #endif
704 void
705 sanitise_stdfd(void)
707 int nullfd, dupfd;
709 if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
710 fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno));
711 exit(1);
713 while (++dupfd <= 2) {
714 /* Only clobber closed fds */
715 if (fcntl(dupfd, F_GETFL, 0) >= 0)
716 continue;
717 if (dup2(nullfd, dupfd) == -1) {
718 fprintf(stderr, "dup2: %s", strerror(errno));
719 exit(1);
722 if (nullfd > 2)
723 close(nullfd);
726 char *
727 tohex(const void *vp, size_t l)
729 const u_char *p = (const u_char *)vp;
730 char b[3], *r;
731 size_t i, hl;
733 if (l > 65536)
734 return xstrdup("tohex: length > 65536");
736 hl = l * 2 + 1;
737 r = xcalloc(1, hl);
738 for (i = 0; i < l; i++) {
739 snprintf(b, sizeof(b), "%02x", p[i]);
740 strlcat(r, b, hl);
742 return (r);
745 u_int64_t
746 get_u64(const void *vp)
748 const u_char *p = (const u_char *)vp;
749 u_int64_t v;
751 v = (u_int64_t)p[0] << 56;
752 v |= (u_int64_t)p[1] << 48;
753 v |= (u_int64_t)p[2] << 40;
754 v |= (u_int64_t)p[3] << 32;
755 v |= (u_int64_t)p[4] << 24;
756 v |= (u_int64_t)p[5] << 16;
757 v |= (u_int64_t)p[6] << 8;
758 v |= (u_int64_t)p[7];
760 return (v);
763 u_int32_t
764 get_u32(const void *vp)
766 const u_char *p = (const u_char *)vp;
767 u_int32_t v;
769 v = (u_int32_t)p[0] << 24;
770 v |= (u_int32_t)p[1] << 16;
771 v |= (u_int32_t)p[2] << 8;
772 v |= (u_int32_t)p[3];
774 return (v);
777 u_int16_t
778 get_u16(const void *vp)
780 const u_char *p = (const u_char *)vp;
781 u_int16_t v;
783 v = (u_int16_t)p[0] << 8;
784 v |= (u_int16_t)p[1];
786 return (v);
789 void
790 put_u64(void *vp, u_int64_t v)
792 u_char *p = (u_char *)vp;
794 p[0] = (u_char)(v >> 56) & 0xff;
795 p[1] = (u_char)(v >> 48) & 0xff;
796 p[2] = (u_char)(v >> 40) & 0xff;
797 p[3] = (u_char)(v >> 32) & 0xff;
798 p[4] = (u_char)(v >> 24) & 0xff;
799 p[5] = (u_char)(v >> 16) & 0xff;
800 p[6] = (u_char)(v >> 8) & 0xff;
801 p[7] = (u_char)v & 0xff;
804 void
805 put_u32(void *vp, u_int32_t v)
807 u_char *p = (u_char *)vp;
809 p[0] = (u_char)(v >> 24) & 0xff;
810 p[1] = (u_char)(v >> 16) & 0xff;
811 p[2] = (u_char)(v >> 8) & 0xff;
812 p[3] = (u_char)v & 0xff;
816 void
817 put_u16(void *vp, u_int16_t v)
819 u_char *p = (u_char *)vp;
821 p[0] = (u_char)(v >> 8) & 0xff;
822 p[1] = (u_char)v & 0xff;