Annotation of src/usr.bin/ssh/misc.c, Revision 1.162
1.162 ! dtucker 1: /* $OpenBSD: misc.c,v 1.161 2021/02/15 20:36:35 markus Exp $ */
1.1 markus 2: /*
3: * Copyright (c) 2000 Markus Friedl. All rights reserved.
1.148 djm 4: * Copyright (c) 2005-2020 Damien Miller. All rights reserved.
5: * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
1.1 markus 6: *
1.148 djm 7: * Permission to use, copy, modify, and distribute this software for any
8: * purpose with or without fee is hereby granted, provided that the above
9: * copyright notice and this permission notice appear in all copies.
1.1 markus 10: *
1.148 djm 11: * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17: * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
1.1 markus 18: */
19:
1.148 djm 20:
1.64 deraadt 21: #include <sys/types.h>
1.45 stevesk 22: #include <sys/ioctl.h>
1.53 stevesk 23: #include <sys/socket.h>
1.112 djm 24: #include <sys/stat.h>
1.101 dtucker 25: #include <sys/time.h>
1.112 djm 26: #include <sys/wait.h>
1.94 millert 27: #include <sys/un.h>
1.38 stevesk 28:
29: #include <net/if.h>
1.53 stevesk 30: #include <netinet/in.h>
1.83 djm 31: #include <netinet/ip.h>
1.44 stevesk 32: #include <netinet/tcp.h>
1.133 naddy 33: #include <arpa/inet.h>
1.43 stevesk 34:
1.92 djm 35: #include <ctype.h>
1.58 stevesk 36: #include <errno.h>
1.55 stevesk 37: #include <fcntl.h>
1.66 dtucker 38: #include <netdb.h>
1.43 stevesk 39: #include <paths.h>
1.54 stevesk 40: #include <pwd.h>
1.112 djm 41: #include <libgen.h>
1.96 deraadt 42: #include <limits.h>
1.136 djm 43: #include <poll.h>
1.112 djm 44: #include <signal.h>
1.57 stevesk 45: #include <stdarg.h>
1.63 stevesk 46: #include <stdio.h>
1.62 stevesk 47: #include <stdlib.h>
1.60 stevesk 48: #include <string.h>
1.59 stevesk 49: #include <unistd.h>
1.1 markus 50:
1.64 deraadt 51: #include "xmalloc.h"
1.1 markus 52: #include "misc.h"
53: #include "log.h"
1.56 dtucker 54: #include "ssh.h"
1.112 djm 55: #include "sshbuf.h"
56: #include "ssherr.h"
1.1 markus 57:
1.12 markus 58: /* remove newline at end of string */
1.1 markus 59: char *
60: chop(char *s)
61: {
62: char *t = s;
63: while (*t) {
1.13 deraadt 64: if (*t == '\n' || *t == '\r') {
1.1 markus 65: *t = '\0';
66: return s;
67: }
68: t++;
69: }
70: return s;
71:
72: }
73:
1.12 markus 74: /* set/unset filedescriptor to non-blocking */
1.24 djm 75: int
1.1 markus 76: set_nonblock(int fd)
77: {
78: int val;
1.8 markus 79:
1.103 krw 80: val = fcntl(fd, F_GETFL);
1.139 deraadt 81: if (val == -1) {
1.103 krw 82: error("fcntl(%d, F_GETFL): %s", fd, strerror(errno));
1.24 djm 83: return (-1);
1.1 markus 84: }
85: if (val & O_NONBLOCK) {
1.24 djm 86: debug3("fd %d is O_NONBLOCK", fd);
87: return (0);
1.1 markus 88: }
1.21 markus 89: debug2("fd %d setting O_NONBLOCK", fd);
1.1 markus 90: val |= O_NONBLOCK;
1.24 djm 91: if (fcntl(fd, F_SETFL, val) == -1) {
92: debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
93: strerror(errno));
94: return (-1);
95: }
96: return (0);
1.8 markus 97: }
98:
1.24 djm 99: int
1.8 markus 100: unset_nonblock(int fd)
101: {
102: int val;
103:
1.103 krw 104: val = fcntl(fd, F_GETFL);
1.139 deraadt 105: if (val == -1) {
1.103 krw 106: error("fcntl(%d, F_GETFL): %s", fd, strerror(errno));
1.24 djm 107: return (-1);
1.8 markus 108: }
109: if (!(val & O_NONBLOCK)) {
1.24 djm 110: debug3("fd %d is not O_NONBLOCK", fd);
111: return (0);
1.8 markus 112: }
1.10 markus 113: debug("fd %d clearing O_NONBLOCK", fd);
1.8 markus 114: val &= ~O_NONBLOCK;
1.24 djm 115: if (fcntl(fd, F_SETFL, val) == -1) {
116: debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
1.18 markus 117: fd, strerror(errno));
1.24 djm 118: return (-1);
119: }
120: return (0);
1.66 dtucker 121: }
122:
123: const char *
124: ssh_gai_strerror(int gaierr)
125: {
1.91 djm 126: if (gaierr == EAI_SYSTEM && errno != 0)
1.67 dtucker 127: return strerror(errno);
128: return gai_strerror(gaierr);
1.15 stevesk 129: }
130:
131: /* disable nagle on socket */
132: void
133: set_nodelay(int fd)
134: {
1.17 stevesk 135: int opt;
136: socklen_t optlen;
1.15 stevesk 137:
1.16 stevesk 138: optlen = sizeof opt;
139: if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
1.23 markus 140: debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
1.16 stevesk 141: return;
142: }
143: if (opt == 1) {
144: debug2("fd %d is TCP_NODELAY", fd);
145: return;
146: }
147: opt = 1;
1.20 markus 148: debug2("fd %d setting TCP_NODELAY", fd);
1.16 stevesk 149: if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
1.15 stevesk 150: error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
1.117 djm 151: }
152:
153: /* Allow local port reuse in TIME_WAIT */
154: int
155: set_reuseaddr(int fd)
156: {
157: int on = 1;
158:
159: if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) {
160: error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
161: return -1;
162: }
163: return 0;
164: }
165:
1.118 djm 166: /* Get/set routing domain */
167: char *
168: get_rdomain(int fd)
169: {
170: int rtable;
171: char *ret;
172: socklen_t len = sizeof(rtable);
173:
174: if (getsockopt(fd, SOL_SOCKET, SO_RTABLE, &rtable, &len) == -1) {
175: error("Failed to get routing domain for fd %d: %s",
176: fd, strerror(errno));
177: return NULL;
178: }
179: xasprintf(&ret, "%d", rtable);
180: return ret;
181: }
182:
1.117 djm 183: int
184: set_rdomain(int fd, const char *name)
185: {
186: int rtable;
187: const char *errstr;
188:
189: if (name == NULL)
190: return 0; /* default table */
191:
192: rtable = (int)strtonum(name, 0, 255, &errstr);
193: if (errstr != NULL) {
194: /* Shouldn't happen */
195: error("Invalid routing domain \"%s\": %s", name, errstr);
196: return -1;
197: }
198: if (setsockopt(fd, SOL_SOCKET, SO_RTABLE,
199: &rtable, sizeof(rtable)) == -1) {
200: error("Failed to set routing domain %d on fd %d: %s",
201: rtable, fd, strerror(errno));
202: return -1;
203: }
1.136 djm 204: return 0;
1.156 djm 205: }
206:
207: int
208: get_sock_af(int fd)
209: {
210: struct sockaddr_storage to;
211: socklen_t tolen = sizeof(to);
212:
213: memset(&to, 0, sizeof(to));
214: if (getsockname(fd, (struct sockaddr *)&to, &tolen) == -1)
215: return -1;
216: return to.ss_family;
217: }
218:
219: void
220: set_sock_tos(int fd, int tos)
221: {
222: int af;
223:
224: switch ((af = get_sock_af(fd))) {
225: case -1:
226: /* assume not a socket */
227: break;
228: case AF_INET:
229: debug3_f("set socket %d IP_TOS 0x%02x", fd, tos);
230: if (setsockopt(fd, IPPROTO_IP, IP_TOS,
231: &tos, sizeof(tos)) == -1) {
232: error("setsockopt socket %d IP_TOS %d: %s:",
233: fd, tos, strerror(errno));
234: }
235: break;
236: case AF_INET6:
237: debug3_f("set socket %d IPV6_TCLASS 0x%02x", fd, tos);
238: if (setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS,
239: &tos, sizeof(tos)) == -1) {
240: error("setsockopt socket %d IPV6_TCLASS %d: %.100s:",
241: fd, tos, strerror(errno));
242: }
243: break;
244: default:
245: debug2_f("unsupported socket family %d", af);
246: break;
247: }
1.136 djm 248: }
249:
250: /*
1.143 dtucker 251: * Wait up to *timeoutp milliseconds for events on fd. Updates
1.136 djm 252: * *timeoutp with time remaining.
253: * Returns 0 if fd ready or -1 on timeout or error (see errno).
254: */
1.143 dtucker 255: static int
256: waitfd(int fd, int *timeoutp, short events)
1.136 djm 257: {
258: struct pollfd pfd;
259: struct timeval t_start;
260: int oerrno, r;
261:
262: pfd.fd = fd;
1.143 dtucker 263: pfd.events = events;
1.136 djm 264: for (; *timeoutp >= 0;) {
1.159 dtucker 265: monotime_tv(&t_start);
1.136 djm 266: r = poll(&pfd, 1, *timeoutp);
267: oerrno = errno;
268: ms_subtract_diff(&t_start, timeoutp);
269: errno = oerrno;
270: if (r > 0)
271: return 0;
1.153 djm 272: else if (r == -1 && errno != EAGAIN && errno != EINTR)
1.136 djm 273: return -1;
274: else if (r == 0)
275: break;
276: }
277: /* timeout */
278: errno = ETIMEDOUT;
279: return -1;
280: }
281:
282: /*
1.143 dtucker 283: * Wait up to *timeoutp milliseconds for fd to be readable. Updates
284: * *timeoutp with time remaining.
285: * Returns 0 if fd ready or -1 on timeout or error (see errno).
286: */
287: int
288: waitrfd(int fd, int *timeoutp) {
289: return waitfd(fd, timeoutp, POLLIN);
290: }
291:
292: /*
1.136 djm 293: * Attempt a non-blocking connect(2) to the specified address, waiting up to
294: * *timeoutp milliseconds for the connection to complete. If the timeout is
295: * <=0, then wait indefinitely.
296: *
297: * Returns 0 on success or -1 on failure.
298: */
299: int
300: timeout_connect(int sockfd, const struct sockaddr *serv_addr,
301: socklen_t addrlen, int *timeoutp)
302: {
303: int optval = 0;
304: socklen_t optlen = sizeof(optval);
305:
306: /* No timeout: just do a blocking connect() */
307: if (timeoutp == NULL || *timeoutp <= 0)
308: return connect(sockfd, serv_addr, addrlen);
309:
310: set_nonblock(sockfd);
1.153 djm 311: for (;;) {
312: if (connect(sockfd, serv_addr, addrlen) == 0) {
313: /* Succeeded already? */
314: unset_nonblock(sockfd);
315: return 0;
316: } else if (errno == EINTR)
317: continue;
318: else if (errno != EINPROGRESS)
319: return -1;
320: break;
321: }
1.136 djm 322:
1.143 dtucker 323: if (waitfd(sockfd, timeoutp, POLLIN | POLLOUT) == -1)
1.136 djm 324: return -1;
325:
326: /* Completed or failed */
327: if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, &optlen) == -1) {
328: debug("getsockopt: %s", strerror(errno));
329: return -1;
330: }
331: if (optval != 0) {
332: errno = optval;
333: return -1;
334: }
335: unset_nonblock(sockfd);
1.117 djm 336: return 0;
1.72 reyk 337: }
338:
1.1 markus 339: /* Characters considered whitespace in strsep calls. */
340: #define WHITESPACE " \t\r\n"
1.46 dtucker 341: #define QUOTE "\""
1.1 markus 342:
1.12 markus 343: /* return next token in configuration line */
1.129 djm 344: static char *
345: strdelim_internal(char **s, int split_equals)
1.1 markus 346: {
1.126 djm 347: char *old;
1.1 markus 348: int wspace = 0;
349:
350: if (*s == NULL)
351: return NULL;
352:
353: old = *s;
354:
1.129 djm 355: *s = strpbrk(*s,
356: split_equals ? WHITESPACE QUOTE "=" : WHITESPACE QUOTE);
1.1 markus 357: if (*s == NULL)
358: return (old);
359:
1.46 dtucker 360: if (*s[0] == '\"') {
361: memmove(*s, *s + 1, strlen(*s)); /* move nul too */
362: /* Find matching quote */
1.126 djm 363: if ((*s = strpbrk(*s, QUOTE)) == NULL) {
364: return (NULL); /* no matching quote */
365: } else {
366: *s[0] = '\0';
367: *s += strspn(*s + 1, WHITESPACE) + 1;
368: return (old);
1.46 dtucker 369: }
370: }
371:
1.1 markus 372: /* Allow only one '=' to be skipped */
1.129 djm 373: if (split_equals && *s[0] == '=')
1.1 markus 374: wspace = 1;
375: *s[0] = '\0';
376:
1.46 dtucker 377: /* Skip any extra whitespace after first token */
1.1 markus 378: *s += strspn(*s + 1, WHITESPACE) + 1;
1.129 djm 379: if (split_equals && *s[0] == '=' && !wspace)
1.1 markus 380: *s += strspn(*s + 1, WHITESPACE) + 1;
381:
382: return (old);
1.129 djm 383: }
384:
385: /*
386: * Return next token in configuration line; splts on whitespace or a
387: * single '=' character.
388: */
389: char *
390: strdelim(char **s)
391: {
392: return strdelim_internal(s, 1);
393: }
394:
395: /*
396: * Return next token in configuration line; splts on whitespace only.
397: */
398: char *
399: strdelimw(char **s)
400: {
401: return strdelim_internal(s, 0);
1.2 markus 402: }
403:
404: struct passwd *
405: pwcopy(struct passwd *pw)
406: {
1.49 djm 407: struct passwd *copy = xcalloc(1, sizeof(*copy));
1.4 deraadt 408:
1.2 markus 409: copy->pw_name = xstrdup(pw->pw_name);
410: copy->pw_passwd = xstrdup(pw->pw_passwd);
1.4 deraadt 411: copy->pw_gecos = xstrdup(pw->pw_gecos);
1.2 markus 412: copy->pw_uid = pw->pw_uid;
413: copy->pw_gid = pw->pw_gid;
1.11 markus 414: copy->pw_expire = pw->pw_expire;
415: copy->pw_change = pw->pw_change;
1.2 markus 416: copy->pw_class = xstrdup(pw->pw_class);
417: copy->pw_dir = xstrdup(pw->pw_dir);
418: copy->pw_shell = xstrdup(pw->pw_shell);
419: return copy;
1.5 stevesk 420: }
421:
1.12 markus 422: /*
423: * Convert ASCII string to TCP/IP port number.
1.70 djm 424: * Port must be >=0 and <=65535.
425: * Return -1 if invalid.
1.12 markus 426: */
427: int
428: a2port(const char *s)
1.5 stevesk 429: {
1.133 naddy 430: struct servent *se;
1.70 djm 431: long long port;
432: const char *errstr;
1.5 stevesk 433:
1.70 djm 434: port = strtonum(s, 0, 65535, &errstr);
1.133 naddy 435: if (errstr == NULL)
436: return (int)port;
437: if ((se = getservbyname(s, "tcp")) != NULL)
438: return ntohs(se->s_port);
439: return -1;
1.9 stevesk 440: }
441:
1.36 reyk 442: int
443: a2tun(const char *s, int *remote)
444: {
445: const char *errstr = NULL;
446: char *sp, *ep;
447: int tun;
448:
449: if (remote != NULL) {
1.37 reyk 450: *remote = SSH_TUNID_ANY;
1.36 reyk 451: sp = xstrdup(s);
452: if ((ep = strchr(sp, ':')) == NULL) {
1.89 djm 453: free(sp);
1.36 reyk 454: return (a2tun(s, NULL));
455: }
456: ep[0] = '\0'; ep++;
457: *remote = a2tun(ep, NULL);
458: tun = a2tun(sp, NULL);
1.89 djm 459: free(sp);
1.37 reyk 460: return (*remote == SSH_TUNID_ERR ? *remote : tun);
1.36 reyk 461: }
462:
463: if (strcasecmp(s, "any") == 0)
1.37 reyk 464: return (SSH_TUNID_ANY);
1.36 reyk 465:
1.37 reyk 466: tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
467: if (errstr != NULL)
468: return (SSH_TUNID_ERR);
1.36 reyk 469:
470: return (tun);
471: }
472:
1.9 stevesk 473: #define SECONDS 1
474: #define MINUTES (SECONDS * 60)
475: #define HOURS (MINUTES * 60)
476: #define DAYS (HOURS * 24)
477: #define WEEKS (DAYS * 7)
478:
1.12 markus 479: /*
480: * Convert a time string into seconds; format is
481: * a sequence of:
482: * time[qualifier]
483: *
484: * Valid time qualifiers are:
485: * <none> seconds
486: * s|S seconds
487: * m|M minutes
488: * h|H hours
489: * d|D days
490: * w|W weeks
491: *
492: * Examples:
493: * 90m 90 minutes
494: * 1h30m 90 minutes
495: * 2d 2 days
496: * 1w 1 week
497: *
498: * Return -1 if time string is invalid.
499: */
1.158 dtucker 500: int
1.12 markus 501: convtime(const char *s)
1.9 stevesk 502: {
1.149 dtucker 503: long total, secs, multiplier;
1.9 stevesk 504: const char *p;
505: char *endp;
506:
507: errno = 0;
508: total = 0;
509: p = s;
510:
511: if (p == NULL || *p == '\0')
512: return -1;
513:
514: while (*p) {
515: secs = strtol(p, &endp, 10);
516: if (p == endp ||
1.158 dtucker 517: (errno == ERANGE && (secs == INT_MIN || secs == INT_MAX)) ||
1.9 stevesk 518: secs < 0)
519: return -1;
520:
1.149 dtucker 521: multiplier = 1;
1.9 stevesk 522: switch (*endp++) {
523: case '\0':
524: endp--;
1.48 deraadt 525: break;
1.9 stevesk 526: case 's':
527: case 'S':
528: break;
529: case 'm':
530: case 'M':
1.108 dtucker 531: multiplier = MINUTES;
1.9 stevesk 532: break;
533: case 'h':
534: case 'H':
1.108 dtucker 535: multiplier = HOURS;
1.9 stevesk 536: break;
537: case 'd':
538: case 'D':
1.108 dtucker 539: multiplier = DAYS;
1.9 stevesk 540: break;
541: case 'w':
542: case 'W':
1.108 dtucker 543: multiplier = WEEKS;
1.9 stevesk 544: break;
545: default:
546: return -1;
547: }
1.160 dtucker 548: if (secs > INT_MAX / multiplier)
1.108 dtucker 549: return -1;
550: secs *= multiplier;
1.160 dtucker 551: if (total > INT_MAX - secs)
1.108 dtucker 552: return -1;
1.9 stevesk 553: total += secs;
554: if (total < 0)
555: return -1;
556: p = endp;
557: }
558:
559: return total;
1.148 djm 560: }
561:
562: #define TF_BUFS 8
563: #define TF_LEN 9
564:
565: const char *
566: fmt_timeframe(time_t t)
567: {
568: char *buf;
569: static char tfbuf[TF_BUFS][TF_LEN]; /* ring buffer */
570: static int idx = 0;
571: unsigned int sec, min, hrs, day;
572: unsigned long long week;
573:
574: buf = tfbuf[idx++];
575: if (idx == TF_BUFS)
576: idx = 0;
577:
578: week = t;
579:
580: sec = week % 60;
581: week /= 60;
582: min = week % 60;
583: week /= 60;
584: hrs = week % 24;
585: week /= 24;
586: day = week % 7;
587: week /= 7;
588:
589: if (week > 0)
590: snprintf(buf, TF_LEN, "%02lluw%01ud%02uh", week, day, hrs);
591: else if (day > 0)
592: snprintf(buf, TF_LEN, "%01ud%02uh%02um", day, hrs, min);
593: else
594: snprintf(buf, TF_LEN, "%02u:%02u:%02u", hrs, min, sec);
595:
596: return (buf);
1.56 dtucker 597: }
598:
599: /*
600: * Returns a standardized host+port identifier string.
601: * Caller must free returned string.
602: */
603: char *
604: put_host_port(const char *host, u_short port)
605: {
606: char *hoststr;
607:
608: if (port == 0 || port == SSH_DEFAULT_PORT)
609: return(xstrdup(host));
1.138 deraadt 610: if (asprintf(&hoststr, "[%s]:%d", host, (int)port) == -1)
1.56 dtucker 611: fatal("put_host_port: asprintf: %s", strerror(errno));
612: debug3("put_host_port: %s", hoststr);
613: return hoststr;
1.28 djm 614: }
615:
616: /*
617: * Search for next delimiter between hostnames/addresses and ports.
618: * Argument may be modified (for termination).
619: * Returns *cp if parsing succeeds.
1.114 millert 620: * *cp is set to the start of the next field, if one was found.
621: * The delimiter char, if present, is stored in delim.
1.28 djm 622: * If this is the last field, *cp is set to NULL.
623: */
1.137 dtucker 624: char *
1.114 millert 625: hpdelim2(char **cp, char *delim)
1.28 djm 626: {
627: char *s, *old;
628:
629: if (cp == NULL || *cp == NULL)
630: return NULL;
631:
632: old = s = *cp;
633: if (*s == '[') {
634: if ((s = strchr(s, ']')) == NULL)
635: return NULL;
636: else
637: s++;
638: } else if ((s = strpbrk(s, ":/")) == NULL)
639: s = *cp + strlen(*cp); /* skip to end (see first case below) */
640:
641: switch (*s) {
642: case '\0':
643: *cp = NULL; /* no more fields*/
644: break;
1.29 deraadt 645:
1.28 djm 646: case ':':
647: case '/':
1.114 millert 648: if (delim != NULL)
649: *delim = *s;
1.28 djm 650: *s = '\0'; /* terminate */
651: *cp = s + 1;
652: break;
1.29 deraadt 653:
1.28 djm 654: default:
655: return NULL;
656: }
657:
658: return old;
1.6 mouring 659: }
660:
661: char *
1.114 millert 662: hpdelim(char **cp)
663: {
664: return hpdelim2(cp, NULL);
665: }
666:
667: char *
1.6 mouring 668: cleanhostname(char *host)
669: {
670: if (*host == '[' && host[strlen(host) - 1] == ']') {
671: host[strlen(host) - 1] = '\0';
672: return (host + 1);
673: } else
674: return host;
675: }
676:
677: char *
678: colon(char *cp)
679: {
680: int flag = 0;
681:
682: if (*cp == ':') /* Leading colon is part of file name. */
1.76 djm 683: return NULL;
1.6 mouring 684: if (*cp == '[')
685: flag = 1;
686:
687: for (; *cp; ++cp) {
688: if (*cp == '@' && *(cp+1) == '[')
689: flag = 1;
690: if (*cp == ']' && *(cp+1) == ':' && flag)
691: return (cp+1);
692: if (*cp == ':' && !flag)
693: return (cp);
694: if (*cp == '/')
1.76 djm 695: return NULL;
1.6 mouring 696: }
1.76 djm 697: return NULL;
1.105 djm 698: }
699:
700: /*
1.114 millert 701: * Parse a [user@]host:[path] string.
702: * Caller must free returned user, host and path.
703: * Any of the pointer return arguments may be NULL (useful for syntax checking).
704: * If user was not specified then *userp will be set to NULL.
705: * If host was not specified then *hostp will be set to NULL.
706: * If path was not specified then *pathp will be set to ".".
707: * Returns 0 on success, -1 on failure.
708: */
709: int
710: parse_user_host_path(const char *s, char **userp, char **hostp, char **pathp)
711: {
712: char *user = NULL, *host = NULL, *path = NULL;
713: char *sdup, *tmp;
714: int ret = -1;
715:
716: if (userp != NULL)
717: *userp = NULL;
718: if (hostp != NULL)
719: *hostp = NULL;
720: if (pathp != NULL)
721: *pathp = NULL;
722:
1.116 millert 723: sdup = xstrdup(s);
1.114 millert 724:
725: /* Check for remote syntax: [user@]host:[path] */
726: if ((tmp = colon(sdup)) == NULL)
727: goto out;
728:
729: /* Extract optional path */
730: *tmp++ = '\0';
731: if (*tmp == '\0')
732: tmp = ".";
733: path = xstrdup(tmp);
734:
735: /* Extract optional user and mandatory host */
736: tmp = strrchr(sdup, '@');
737: if (tmp != NULL) {
738: *tmp++ = '\0';
739: host = xstrdup(cleanhostname(tmp));
740: if (*sdup != '\0')
741: user = xstrdup(sdup);
742: } else {
743: host = xstrdup(cleanhostname(sdup));
744: user = NULL;
745: }
746:
747: /* Success */
748: if (userp != NULL) {
749: *userp = user;
750: user = NULL;
751: }
752: if (hostp != NULL) {
753: *hostp = host;
754: host = NULL;
1.116 millert 755: }
1.114 millert 756: if (pathp != NULL) {
757: *pathp = path;
758: path = NULL;
1.116 millert 759: }
1.114 millert 760: ret = 0;
761: out:
762: free(sdup);
763: free(user);
764: free(host);
765: free(path);
766: return ret;
767: }
768:
769: /*
1.105 djm 770: * Parse a [user@]host[:port] string.
771: * Caller must free returned user and host.
772: * Any of the pointer return arguments may be NULL (useful for syntax checking).
773: * If user was not specified then *userp will be set to NULL.
774: * If port was not specified then *portp will be -1.
775: * Returns 0 on success, -1 on failure.
776: */
777: int
778: parse_user_host_port(const char *s, char **userp, char **hostp, int *portp)
779: {
780: char *sdup, *cp, *tmp;
781: char *user = NULL, *host = NULL;
782: int port = -1, ret = -1;
783:
784: if (userp != NULL)
785: *userp = NULL;
786: if (hostp != NULL)
787: *hostp = NULL;
788: if (portp != NULL)
789: *portp = -1;
790:
791: if ((sdup = tmp = strdup(s)) == NULL)
792: return -1;
793: /* Extract optional username */
1.114 millert 794: if ((cp = strrchr(tmp, '@')) != NULL) {
1.105 djm 795: *cp = '\0';
796: if (*tmp == '\0')
797: goto out;
798: if ((user = strdup(tmp)) == NULL)
799: goto out;
800: tmp = cp + 1;
801: }
802: /* Extract mandatory hostname */
803: if ((cp = hpdelim(&tmp)) == NULL || *cp == '\0')
804: goto out;
805: host = xstrdup(cleanhostname(cp));
806: /* Convert and verify optional port */
807: if (tmp != NULL && *tmp != '\0') {
808: if ((port = a2port(tmp)) <= 0)
809: goto out;
810: }
811: /* Success */
812: if (userp != NULL) {
813: *userp = user;
814: user = NULL;
815: }
816: if (hostp != NULL) {
817: *hostp = host;
818: host = NULL;
819: }
820: if (portp != NULL)
821: *portp = port;
822: ret = 0;
823: out:
824: free(sdup);
825: free(user);
826: free(host);
827: return ret;
1.7 mouring 828: }
829:
1.114 millert 830: /*
831: * Converts a two-byte hex string to decimal.
832: * Returns the decimal value or -1 for invalid input.
833: */
834: static int
835: hexchar(const char *s)
836: {
837: unsigned char result[2];
838: int i;
839:
840: for (i = 0; i < 2; i++) {
841: if (s[i] >= '0' && s[i] <= '9')
842: result[i] = (unsigned char)(s[i] - '0');
843: else if (s[i] >= 'a' && s[i] <= 'f')
844: result[i] = (unsigned char)(s[i] - 'a') + 10;
845: else if (s[i] >= 'A' && s[i] <= 'F')
846: result[i] = (unsigned char)(s[i] - 'A') + 10;
847: else
848: return -1;
849: }
850: return (result[0] << 4) | result[1];
851: }
852:
853: /*
854: * Decode an url-encoded string.
855: * Returns a newly allocated string on success or NULL on failure.
856: */
857: static char *
858: urldecode(const char *src)
859: {
860: char *ret, *dst;
861: int ch;
862:
863: ret = xmalloc(strlen(src) + 1);
864: for (dst = ret; *src != '\0'; src++) {
865: switch (*src) {
866: case '+':
867: *dst++ = ' ';
868: break;
869: case '%':
870: if (!isxdigit((unsigned char)src[1]) ||
871: !isxdigit((unsigned char)src[2]) ||
872: (ch = hexchar(src + 1)) == -1) {
873: free(ret);
874: return NULL;
875: }
876: *dst++ = ch;
877: src += 2;
878: break;
879: default:
880: *dst++ = *src;
881: break;
882: }
883: }
884: *dst = '\0';
885:
886: return ret;
887: }
888:
889: /*
890: * Parse an (scp|ssh|sftp)://[user@]host[:port][/path] URI.
891: * See https://tools.ietf.org/html/draft-ietf-secsh-scp-sftp-ssh-uri-04
892: * Either user or path may be url-encoded (but not host or port).
893: * Caller must free returned user, host and path.
894: * Any of the pointer return arguments may be NULL (useful for syntax checking)
895: * but the scheme must always be specified.
896: * If user was not specified then *userp will be set to NULL.
897: * If port was not specified then *portp will be -1.
898: * If path was not specified then *pathp will be set to NULL.
899: * Returns 0 on success, 1 if non-uri/wrong scheme, -1 on error/invalid uri.
900: */
901: int
902: parse_uri(const char *scheme, const char *uri, char **userp, char **hostp,
903: int *portp, char **pathp)
904: {
905: char *uridup, *cp, *tmp, ch;
906: char *user = NULL, *host = NULL, *path = NULL;
907: int port = -1, ret = -1;
908: size_t len;
909:
910: len = strlen(scheme);
911: if (strncmp(uri, scheme, len) != 0 || strncmp(uri + len, "://", 3) != 0)
912: return 1;
913: uri += len + 3;
914:
915: if (userp != NULL)
916: *userp = NULL;
917: if (hostp != NULL)
918: *hostp = NULL;
919: if (portp != NULL)
920: *portp = -1;
921: if (pathp != NULL)
922: *pathp = NULL;
923:
924: uridup = tmp = xstrdup(uri);
925:
926: /* Extract optional ssh-info (username + connection params) */
927: if ((cp = strchr(tmp, '@')) != NULL) {
928: char *delim;
929:
930: *cp = '\0';
931: /* Extract username and connection params */
932: if ((delim = strchr(tmp, ';')) != NULL) {
933: /* Just ignore connection params for now */
934: *delim = '\0';
935: }
936: if (*tmp == '\0') {
937: /* Empty username */
938: goto out;
939: }
940: if ((user = urldecode(tmp)) == NULL)
941: goto out;
942: tmp = cp + 1;
943: }
944:
945: /* Extract mandatory hostname */
946: if ((cp = hpdelim2(&tmp, &ch)) == NULL || *cp == '\0')
947: goto out;
948: host = xstrdup(cleanhostname(cp));
949: if (!valid_domain(host, 0, NULL))
950: goto out;
951:
952: if (tmp != NULL && *tmp != '\0') {
953: if (ch == ':') {
954: /* Convert and verify port. */
955: if ((cp = strchr(tmp, '/')) != NULL)
956: *cp = '\0';
957: if ((port = a2port(tmp)) <= 0)
958: goto out;
959: tmp = cp ? cp + 1 : NULL;
960: }
961: if (tmp != NULL && *tmp != '\0') {
962: /* Extract optional path */
963: if ((path = urldecode(tmp)) == NULL)
964: goto out;
965: }
966: }
967:
968: /* Success */
969: if (userp != NULL) {
970: *userp = user;
971: user = NULL;
972: }
973: if (hostp != NULL) {
974: *hostp = host;
975: host = NULL;
976: }
977: if (portp != NULL)
978: *portp = port;
979: if (pathp != NULL) {
980: *pathp = path;
981: path = NULL;
982: }
983: ret = 0;
984: out:
985: free(uridup);
986: free(user);
987: free(host);
988: free(path);
989: return ret;
990: }
991:
1.12 markus 992: /* function to assist building execv() arguments */
1.7 mouring 993: void
994: addargs(arglist *args, char *fmt, ...)
995: {
996: va_list ap;
1.42 djm 997: char *cp;
1.25 avsm 998: u_int nalloc;
1.42 djm 999: int r;
1.7 mouring 1000:
1001: va_start(ap, fmt);
1.42 djm 1002: r = vasprintf(&cp, fmt, ap);
1.7 mouring 1003: va_end(ap);
1.42 djm 1004: if (r == -1)
1005: fatal("addargs: argument too long");
1.7 mouring 1006:
1.22 markus 1007: nalloc = args->nalloc;
1.7 mouring 1008: if (args->list == NULL) {
1.22 markus 1009: nalloc = 32;
1.7 mouring 1010: args->num = 0;
1.22 markus 1011: } else if (args->num+2 >= nalloc)
1012: nalloc *= 2;
1.7 mouring 1013:
1.110 deraadt 1014: args->list = xrecallocarray(args->list, args->nalloc, nalloc, sizeof(char *));
1.22 markus 1015: args->nalloc = nalloc;
1.42 djm 1016: args->list[args->num++] = cp;
1.7 mouring 1017: args->list[args->num] = NULL;
1.42 djm 1018: }
1019:
1020: void
1021: replacearg(arglist *args, u_int which, char *fmt, ...)
1022: {
1023: va_list ap;
1024: char *cp;
1025: int r;
1026:
1027: va_start(ap, fmt);
1028: r = vasprintf(&cp, fmt, ap);
1029: va_end(ap);
1030: if (r == -1)
1031: fatal("replacearg: argument too long");
1032:
1033: if (which >= args->num)
1034: fatal("replacearg: tried to replace invalid arg %d >= %d",
1035: which, args->num);
1.89 djm 1036: free(args->list[which]);
1.42 djm 1037: args->list[which] = cp;
1038: }
1039:
1040: void
1041: freeargs(arglist *args)
1042: {
1043: u_int i;
1044:
1045: if (args->list != NULL) {
1046: for (i = 0; i < args->num; i++)
1.89 djm 1047: free(args->list[i]);
1048: free(args->list);
1.42 djm 1049: args->nalloc = args->num = 0;
1050: args->list = NULL;
1051: }
1.30 djm 1052: }
1053:
1054: /*
1055: * Expands tildes in the file name. Returns data allocated by xmalloc.
1056: * Warning: this calls getpw*.
1057: */
1058: char *
1059: tilde_expand_filename(const char *filename, uid_t uid)
1060: {
1.87 tedu 1061: const char *path, *sep;
1062: char user[128], *ret;
1.30 djm 1063: struct passwd *pw;
1.32 djm 1064: u_int len, slash;
1.30 djm 1065:
1066: if (*filename != '~')
1067: return (xstrdup(filename));
1068: filename++;
1069:
1070: path = strchr(filename, '/');
1071: if (path != NULL && path > filename) { /* ~user/path */
1.32 djm 1072: slash = path - filename;
1073: if (slash > sizeof(user) - 1)
1.30 djm 1074: fatal("tilde_expand_filename: ~username too long");
1.32 djm 1075: memcpy(user, filename, slash);
1076: user[slash] = '\0';
1.30 djm 1077: if ((pw = getpwnam(user)) == NULL)
1078: fatal("tilde_expand_filename: No such user %s", user);
1079: } else if ((pw = getpwuid(uid)) == NULL) /* ~/path */
1.69 dtucker 1080: fatal("tilde_expand_filename: No such uid %ld", (long)uid);
1.30 djm 1081:
1082: /* Make sure directory has a trailing '/' */
1083: len = strlen(pw->pw_dir);
1.88 tedu 1084: if (len == 0 || pw->pw_dir[len - 1] != '/')
1.87 tedu 1085: sep = "/";
1086: else
1087: sep = "";
1.30 djm 1088:
1089: /* Skip leading '/' from specified path */
1090: if (path != NULL)
1091: filename = path + 1;
1.87 tedu 1092:
1.96 deraadt 1093: if (xasprintf(&ret, "%s%s%s", pw->pw_dir, sep, filename) >= PATH_MAX)
1.30 djm 1094: fatal("tilde_expand_filename: Path too long");
1095:
1.87 tedu 1096: return (ret);
1.31 djm 1097: }
1098:
1099: /*
1.150 dtucker 1100: * Expand a string with a set of %[char] escapes and/or ${ENVIRONMENT}
1101: * substitutions. A number of escapes may be specified as
1102: * (char *escape_chars, char *replacement) pairs. The list must be terminated
1103: * by a NULL escape_char. Returns replaced string in memory allocated by
1104: * xmalloc which the caller must free.
1.31 djm 1105: */
1.150 dtucker 1106: static char *
1107: vdollar_percent_expand(int *parseerror, int dollar, int percent,
1108: const char *string, va_list ap)
1.31 djm 1109: {
1110: #define EXPAND_MAX_KEYS 16
1.150 dtucker 1111: u_int num_keys = 0, i;
1.31 djm 1112: struct {
1113: const char *key;
1114: const char *repl;
1115: } keys[EXPAND_MAX_KEYS];
1.140 djm 1116: struct sshbuf *buf;
1.150 dtucker 1117: int r, missingvar = 0;
1118: char *ret = NULL, *var, *varend, *val;
1119: size_t len;
1.140 djm 1120:
1121: if ((buf = sshbuf_new()) == NULL)
1.155 djm 1122: fatal_f("sshbuf_new failed");
1.150 dtucker 1123: if (parseerror == NULL)
1.155 djm 1124: fatal_f("null parseerror arg");
1.150 dtucker 1125: *parseerror = 1;
1126:
1127: /* Gather keys if we're doing percent expansion. */
1128: if (percent) {
1129: for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
1130: keys[num_keys].key = va_arg(ap, char *);
1131: if (keys[num_keys].key == NULL)
1132: break;
1133: keys[num_keys].repl = va_arg(ap, char *);
1.155 djm 1134: if (keys[num_keys].repl == NULL) {
1135: fatal_f("NULL replacement for token %s",
1136: keys[num_keys].key);
1137: }
1.150 dtucker 1138: }
1139: if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL)
1.155 djm 1140: fatal_f("too many keys");
1.150 dtucker 1141: if (num_keys == 0)
1.155 djm 1142: fatal_f("percent expansion without token list");
1.31 djm 1143: }
1144:
1145: /* Expand string */
1146: for (i = 0; *string != '\0'; string++) {
1.150 dtucker 1147: /* Optionally process ${ENVIRONMENT} expansions. */
1148: if (dollar && string[0] == '$' && string[1] == '{') {
1149: string += 2; /* skip over '${' */
1150: if ((varend = strchr(string, '}')) == NULL) {
1.155 djm 1151: error_f("environment variable '%s' missing "
1152: "closing '}'", string);
1.150 dtucker 1153: goto out;
1154: }
1155: len = varend - string;
1156: if (len == 0) {
1.155 djm 1157: error_f("zero-length environment variable");
1.150 dtucker 1158: goto out;
1159: }
1160: var = xmalloc(len + 1);
1161: (void)strlcpy(var, string, len + 1);
1162: if ((val = getenv(var)) == NULL) {
1.155 djm 1163: error_f("env var ${%s} has no value", var);
1.150 dtucker 1164: missingvar = 1;
1165: } else {
1.155 djm 1166: debug3_f("expand ${%s} -> '%s'", var, val);
1.150 dtucker 1167: if ((r = sshbuf_put(buf, val, strlen(val))) !=0)
1.155 djm 1168: fatal_fr(r, "sshbuf_put ${}");
1.150 dtucker 1169: }
1170: free(var);
1171: string += len;
1172: continue;
1173: }
1174:
1175: /*
1176: * Process percent expansions if we have a list of TOKENs.
1177: * If we're not doing percent expansion everything just gets
1178: * appended here.
1179: */
1180: if (*string != '%' || !percent) {
1.31 djm 1181: append:
1.155 djm 1182: if ((r = sshbuf_put_u8(buf, *string)) != 0)
1183: fatal_fr(r, "sshbuf_put_u8 %%");
1.31 djm 1184: continue;
1185: }
1186: string++;
1.73 djm 1187: /* %% case */
1.31 djm 1188: if (*string == '%')
1189: goto append;
1.150 dtucker 1190: if (*string == '\0') {
1.155 djm 1191: error_f("invalid format");
1.150 dtucker 1192: goto out;
1193: }
1.140 djm 1194: for (i = 0; i < num_keys; i++) {
1195: if (strchr(keys[i].key, *string) != NULL) {
1196: if ((r = sshbuf_put(buf, keys[i].repl,
1.155 djm 1197: strlen(keys[i].repl))) != 0)
1198: fatal_fr(r, "sshbuf_put %%-repl");
1.31 djm 1199: break;
1200: }
1201: }
1.150 dtucker 1202: if (i >= num_keys) {
1.155 djm 1203: error_f("unknown key %%%c", *string);
1.150 dtucker 1204: goto out;
1205: }
1.31 djm 1206: }
1.150 dtucker 1207: if (!missingvar && (ret = sshbuf_dup_string(buf)) == NULL)
1.155 djm 1208: fatal_f("sshbuf_dup_string failed");
1.150 dtucker 1209: *parseerror = 0;
1210: out:
1.140 djm 1211: sshbuf_free(buf);
1.150 dtucker 1212: return *parseerror ? NULL : ret;
1213: #undef EXPAND_MAX_KEYS
1214: }
1215:
1.152 dtucker 1216: /*
1217: * Expand only environment variables.
1218: * Note that although this function is variadic like the other similar
1219: * functions, any such arguments will be unused.
1220: */
1221:
1.150 dtucker 1222: char *
1.152 dtucker 1223: dollar_expand(int *parseerr, const char *string, ...)
1.150 dtucker 1224: {
1225: char *ret;
1226: int err;
1.152 dtucker 1227: va_list ap;
1.150 dtucker 1228:
1.152 dtucker 1229: va_start(ap, string);
1230: ret = vdollar_percent_expand(&err, 1, 0, string, ap);
1231: va_end(ap);
1.150 dtucker 1232: if (parseerr != NULL)
1233: *parseerr = err;
1234: return ret;
1235: }
1236:
1237: /*
1238: * Returns expanded string or NULL if a specified environment variable is
1239: * not defined, or calls fatal if the string is invalid.
1240: */
1241: char *
1242: percent_expand(const char *string, ...)
1243: {
1244: char *ret;
1245: int err;
1246: va_list ap;
1247:
1248: va_start(ap, string);
1249: ret = vdollar_percent_expand(&err, 0, 1, string, ap);
1250: va_end(ap);
1251: if (err)
1.155 djm 1252: fatal_f("failed");
1.150 dtucker 1253: return ret;
1254: }
1255:
1256: /*
1257: * Returns expanded string or NULL if a specified environment variable is
1258: * not defined, or calls fatal if the string is invalid.
1259: */
1260: char *
1261: percent_dollar_expand(const char *string, ...)
1262: {
1263: char *ret;
1264: int err;
1265: va_list ap;
1266:
1267: va_start(ap, string);
1268: ret = vdollar_percent_expand(&err, 1, 1, string, ap);
1269: va_end(ap);
1270: if (err)
1.155 djm 1271: fatal_f("failed");
1.140 djm 1272: return ret;
1.36 reyk 1273: }
1274:
1275: int
1.115 djm 1276: tun_open(int tun, int mode, char **ifname)
1.36 reyk 1277: {
1.37 reyk 1278: struct ifreq ifr;
1.36 reyk 1279: char name[100];
1.37 reyk 1280: int fd = -1, sock;
1.99 sthen 1281: const char *tunbase = "tun";
1282:
1.115 djm 1283: if (ifname != NULL)
1284: *ifname = NULL;
1285:
1.99 sthen 1286: if (mode == SSH_TUNMODE_ETHERNET)
1287: tunbase = "tap";
1.36 reyk 1288:
1.37 reyk 1289: /* Open the tunnel device */
1290: if (tun <= SSH_TUNID_MAX) {
1.99 sthen 1291: snprintf(name, sizeof(name), "/dev/%s%d", tunbase, tun);
1.37 reyk 1292: fd = open(name, O_RDWR);
1293: } else if (tun == SSH_TUNID_ANY) {
1294: for (tun = 100; tun >= 0; tun--) {
1.99 sthen 1295: snprintf(name, sizeof(name), "/dev/%s%d",
1296: tunbase, tun);
1.37 reyk 1297: if ((fd = open(name, O_RDWR)) >= 0)
1298: break;
1.36 reyk 1299: }
1300: } else {
1.155 djm 1301: debug_f("invalid tunnel %u", tun);
1.98 djm 1302: return -1;
1.37 reyk 1303: }
1304:
1.139 deraadt 1305: if (fd == -1) {
1.155 djm 1306: debug_f("%s open: %s", name, strerror(errno));
1.98 djm 1307: return -1;
1.36 reyk 1308: }
1.37 reyk 1309:
1.155 djm 1310: debug_f("%s mode %d fd %d", name, mode, fd);
1.37 reyk 1311:
1.99 sthen 1312: /* Bring interface up if it is not already */
1313: snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d", tunbase, tun);
1314: if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
1.37 reyk 1315: goto failed;
1316:
1.98 djm 1317: if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) {
1.155 djm 1318: debug_f("get interface %s flags: %s", ifr.ifr_name,
1319: strerror(errno));
1.37 reyk 1320: goto failed;
1.98 djm 1321: }
1.40 reyk 1322:
1.98 djm 1323: if (!(ifr.ifr_flags & IFF_UP)) {
1324: ifr.ifr_flags |= IFF_UP;
1325: if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) {
1.155 djm 1326: debug_f("activate interface %s: %s", ifr.ifr_name,
1327: strerror(errno));
1.98 djm 1328: goto failed;
1329: }
1330: }
1.115 djm 1331:
1332: if (ifname != NULL)
1333: *ifname = xstrdup(ifr.ifr_name);
1.37 reyk 1334:
1335: close(sock);
1.98 djm 1336: return fd;
1.37 reyk 1337:
1338: failed:
1339: if (fd >= 0)
1340: close(fd);
1341: if (sock >= 0)
1342: close(sock);
1.98 djm 1343: return -1;
1.35 djm 1344: }
1345:
1346: void
1347: sanitise_stdfd(void)
1348: {
1.41 djm 1349: int nullfd, dupfd;
1.35 djm 1350:
1.41 djm 1351: if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1.71 tobias 1352: fprintf(stderr, "Couldn't open /dev/null: %s\n",
1353: strerror(errno));
1.35 djm 1354: exit(1);
1355: }
1.103 krw 1356: while (++dupfd <= STDERR_FILENO) {
1357: /* Only populate closed fds. */
1358: if (fcntl(dupfd, F_GETFL) == -1 && errno == EBADF) {
1359: if (dup2(nullfd, dupfd) == -1) {
1360: fprintf(stderr, "dup2: %s\n", strerror(errno));
1361: exit(1);
1362: }
1.35 djm 1363: }
1364: }
1.103 krw 1365: if (nullfd > STDERR_FILENO)
1.35 djm 1366: close(nullfd);
1.1 markus 1367: }
1.33 djm 1368:
1369: char *
1.52 djm 1370: tohex(const void *vp, size_t l)
1.33 djm 1371: {
1.52 djm 1372: const u_char *p = (const u_char *)vp;
1.33 djm 1373: char b[3], *r;
1.52 djm 1374: size_t i, hl;
1375:
1376: if (l > 65536)
1377: return xstrdup("tohex: length > 65536");
1.33 djm 1378:
1379: hl = l * 2 + 1;
1.49 djm 1380: r = xcalloc(1, hl);
1.33 djm 1381: for (i = 0; i < l; i++) {
1.52 djm 1382: snprintf(b, sizeof(b), "%02x", p[i]);
1.33 djm 1383: strlcat(r, b, hl);
1384: }
1385: return (r);
1386: }
1.145 djm 1387:
1388: /*
1389: * Extend string *sp by the specified format. If *sp is not NULL (or empty),
1390: * then the separator 'sep' will be prepended before the formatted arguments.
1391: * Extended strings are heap allocated.
1392: */
1393: void
1394: xextendf(char **sp, const char *sep, const char *fmt, ...)
1395: {
1396: va_list ap;
1397: char *tmp1, *tmp2;
1398:
1399: va_start(ap, fmt);
1400: xvasprintf(&tmp1, fmt, ap);
1401: va_end(ap);
1402:
1403: if (*sp == NULL || **sp == '\0') {
1404: free(*sp);
1405: *sp = tmp1;
1406: return;
1407: }
1408: xasprintf(&tmp2, "%s%s%s", *sp, sep == NULL ? "" : sep, tmp1);
1409: free(tmp1);
1410: free(*sp);
1411: *sp = tmp2;
1412: }
1413:
1.33 djm 1414:
1.52 djm 1415: u_int64_t
1416: get_u64(const void *vp)
1417: {
1418: const u_char *p = (const u_char *)vp;
1419: u_int64_t v;
1420:
1421: v = (u_int64_t)p[0] << 56;
1422: v |= (u_int64_t)p[1] << 48;
1423: v |= (u_int64_t)p[2] << 40;
1424: v |= (u_int64_t)p[3] << 32;
1425: v |= (u_int64_t)p[4] << 24;
1426: v |= (u_int64_t)p[5] << 16;
1427: v |= (u_int64_t)p[6] << 8;
1428: v |= (u_int64_t)p[7];
1429:
1430: return (v);
1431: }
1432:
1433: u_int32_t
1434: get_u32(const void *vp)
1435: {
1436: const u_char *p = (const u_char *)vp;
1437: u_int32_t v;
1438:
1439: v = (u_int32_t)p[0] << 24;
1440: v |= (u_int32_t)p[1] << 16;
1441: v |= (u_int32_t)p[2] << 8;
1442: v |= (u_int32_t)p[3];
1443:
1444: return (v);
1445: }
1446:
1.93 djm 1447: u_int32_t
1448: get_u32_le(const void *vp)
1449: {
1450: const u_char *p = (const u_char *)vp;
1451: u_int32_t v;
1452:
1453: v = (u_int32_t)p[0];
1454: v |= (u_int32_t)p[1] << 8;
1455: v |= (u_int32_t)p[2] << 16;
1456: v |= (u_int32_t)p[3] << 24;
1457:
1458: return (v);
1459: }
1460:
1.52 djm 1461: u_int16_t
1462: get_u16(const void *vp)
1463: {
1464: const u_char *p = (const u_char *)vp;
1465: u_int16_t v;
1466:
1467: v = (u_int16_t)p[0] << 8;
1468: v |= (u_int16_t)p[1];
1469:
1470: return (v);
1471: }
1472:
1473: void
1474: put_u64(void *vp, u_int64_t v)
1475: {
1476: u_char *p = (u_char *)vp;
1477:
1478: p[0] = (u_char)(v >> 56) & 0xff;
1479: p[1] = (u_char)(v >> 48) & 0xff;
1480: p[2] = (u_char)(v >> 40) & 0xff;
1481: p[3] = (u_char)(v >> 32) & 0xff;
1482: p[4] = (u_char)(v >> 24) & 0xff;
1483: p[5] = (u_char)(v >> 16) & 0xff;
1484: p[6] = (u_char)(v >> 8) & 0xff;
1485: p[7] = (u_char)v & 0xff;
1486: }
1487:
1488: void
1489: put_u32(void *vp, u_int32_t v)
1490: {
1491: u_char *p = (u_char *)vp;
1492:
1493: p[0] = (u_char)(v >> 24) & 0xff;
1494: p[1] = (u_char)(v >> 16) & 0xff;
1495: p[2] = (u_char)(v >> 8) & 0xff;
1496: p[3] = (u_char)v & 0xff;
1497: }
1498:
1.93 djm 1499: void
1500: put_u32_le(void *vp, u_int32_t v)
1501: {
1502: u_char *p = (u_char *)vp;
1503:
1504: p[0] = (u_char)v & 0xff;
1505: p[1] = (u_char)(v >> 8) & 0xff;
1506: p[2] = (u_char)(v >> 16) & 0xff;
1507: p[3] = (u_char)(v >> 24) & 0xff;
1508: }
1.52 djm 1509:
1510: void
1511: put_u16(void *vp, u_int16_t v)
1512: {
1513: u_char *p = (u_char *)vp;
1514:
1515: p[0] = (u_char)(v >> 8) & 0xff;
1516: p[1] = (u_char)v & 0xff;
1517: }
1.68 dtucker 1518:
1519: void
1520: ms_subtract_diff(struct timeval *start, int *ms)
1521: {
1522: struct timeval diff, finish;
1523:
1.119 dtucker 1524: monotime_tv(&finish);
1525: timersub(&finish, start, &diff);
1.68 dtucker 1526: *ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000);
1527: }
1528:
1529: void
1530: ms_to_timeval(struct timeval *tv, int ms)
1531: {
1532: if (ms < 0)
1533: ms = 0;
1534: tv->tv_sec = ms / 1000;
1535: tv->tv_usec = (ms % 1000) * 1000;
1.90 dtucker 1536: }
1537:
1.119 dtucker 1538: void
1539: monotime_ts(struct timespec *ts)
1540: {
1541: if (clock_gettime(CLOCK_MONOTONIC, ts) != 0)
1542: fatal("clock_gettime: %s", strerror(errno));
1543: }
1544:
1545: void
1546: monotime_tv(struct timeval *tv)
1547: {
1548: struct timespec ts;
1549:
1550: monotime_ts(&ts);
1551: tv->tv_sec = ts.tv_sec;
1552: tv->tv_usec = ts.tv_nsec / 1000;
1553: }
1554:
1.90 dtucker 1555: time_t
1556: monotime(void)
1557: {
1558: struct timespec ts;
1559:
1.119 dtucker 1560: monotime_ts(&ts);
1.90 dtucker 1561: return (ts.tv_sec);
1.102 dtucker 1562: }
1563:
1564: double
1565: monotime_double(void)
1566: {
1567: struct timespec ts;
1568:
1.119 dtucker 1569: monotime_ts(&ts);
1570: return (double)ts.tv_sec + (double)ts.tv_nsec / 1000000000.0;
1.81 djm 1571: }
1572:
1573: void
1574: bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen)
1575: {
1576: bw->buflen = buflen;
1577: bw->rate = kbps;
1.135 dtucker 1578: bw->thresh = buflen;
1.81 djm 1579: bw->lamt = 0;
1580: timerclear(&bw->bwstart);
1581: timerclear(&bw->bwend);
1.135 dtucker 1582: }
1.81 djm 1583:
1584: /* Callback from read/write loop to insert bandwidth-limiting delays */
1585: void
1586: bandwidth_limit(struct bwlimit *bw, size_t read_len)
1587: {
1588: u_int64_t waitlen;
1589: struct timespec ts, rm;
1590:
1.135 dtucker 1591: bw->lamt += read_len;
1.81 djm 1592: if (!timerisset(&bw->bwstart)) {
1.119 dtucker 1593: monotime_tv(&bw->bwstart);
1.81 djm 1594: return;
1595: }
1596: if (bw->lamt < bw->thresh)
1597: return;
1598:
1.119 dtucker 1599: monotime_tv(&bw->bwend);
1.81 djm 1600: timersub(&bw->bwend, &bw->bwstart, &bw->bwend);
1601: if (!timerisset(&bw->bwend))
1602: return;
1603:
1604: bw->lamt *= 8;
1605: waitlen = (double)1000000L * bw->lamt / bw->rate;
1606:
1607: bw->bwstart.tv_sec = waitlen / 1000000L;
1608: bw->bwstart.tv_usec = waitlen % 1000000L;
1609:
1610: if (timercmp(&bw->bwstart, &bw->bwend, >)) {
1611: timersub(&bw->bwstart, &bw->bwend, &bw->bwend);
1612:
1613: /* Adjust the wait time */
1614: if (bw->bwend.tv_sec) {
1615: bw->thresh /= 2;
1616: if (bw->thresh < bw->buflen / 4)
1617: bw->thresh = bw->buflen / 4;
1618: } else if (bw->bwend.tv_usec < 10000) {
1619: bw->thresh *= 2;
1620: if (bw->thresh > bw->buflen * 8)
1621: bw->thresh = bw->buflen * 8;
1622: }
1623:
1624: TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts);
1625: while (nanosleep(&ts, &rm) == -1) {
1626: if (errno != EINTR)
1627: break;
1628: ts = rm;
1629: }
1630: }
1631:
1632: bw->lamt = 0;
1.119 dtucker 1633: monotime_tv(&bw->bwstart);
1.84 djm 1634: }
1635:
1636: /* Make a template filename for mk[sd]temp() */
1637: void
1638: mktemp_proto(char *s, size_t len)
1639: {
1640: const char *tmpdir;
1641: int r;
1642:
1643: if ((tmpdir = getenv("TMPDIR")) != NULL) {
1644: r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir);
1645: if (r > 0 && (size_t)r < len)
1646: return;
1647: }
1648: r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX");
1649: if (r < 0 || (size_t)r >= len)
1.155 djm 1650: fatal_f("template string too short");
1.68 dtucker 1651: }
1.83 djm 1652:
1653: static const struct {
1654: const char *name;
1655: int value;
1656: } ipqos[] = {
1.111 djm 1657: { "none", INT_MAX }, /* can't use 0 here; that's CS0 */
1.83 djm 1658: { "af11", IPTOS_DSCP_AF11 },
1659: { "af12", IPTOS_DSCP_AF12 },
1660: { "af13", IPTOS_DSCP_AF13 },
1.86 djm 1661: { "af21", IPTOS_DSCP_AF21 },
1.83 djm 1662: { "af22", IPTOS_DSCP_AF22 },
1663: { "af23", IPTOS_DSCP_AF23 },
1664: { "af31", IPTOS_DSCP_AF31 },
1665: { "af32", IPTOS_DSCP_AF32 },
1666: { "af33", IPTOS_DSCP_AF33 },
1667: { "af41", IPTOS_DSCP_AF41 },
1668: { "af42", IPTOS_DSCP_AF42 },
1669: { "af43", IPTOS_DSCP_AF43 },
1670: { "cs0", IPTOS_DSCP_CS0 },
1671: { "cs1", IPTOS_DSCP_CS1 },
1672: { "cs2", IPTOS_DSCP_CS2 },
1673: { "cs3", IPTOS_DSCP_CS3 },
1674: { "cs4", IPTOS_DSCP_CS4 },
1675: { "cs5", IPTOS_DSCP_CS5 },
1676: { "cs6", IPTOS_DSCP_CS6 },
1677: { "cs7", IPTOS_DSCP_CS7 },
1678: { "ef", IPTOS_DSCP_EF },
1.146 djm 1679: { "le", IPTOS_DSCP_LE },
1.83 djm 1680: { "lowdelay", IPTOS_LOWDELAY },
1681: { "throughput", IPTOS_THROUGHPUT },
1682: { "reliability", IPTOS_RELIABILITY },
1683: { NULL, -1 }
1684: };
1685:
1686: int
1687: parse_ipqos(const char *cp)
1688: {
1689: u_int i;
1690: char *ep;
1691: long val;
1692:
1693: if (cp == NULL)
1694: return -1;
1695: for (i = 0; ipqos[i].name != NULL; i++) {
1696: if (strcasecmp(cp, ipqos[i].name) == 0)
1697: return ipqos[i].value;
1698: }
1699: /* Try parsing as an integer */
1700: val = strtol(cp, &ep, 0);
1701: if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255)
1702: return -1;
1703: return val;
1704: }
1705:
1.85 stevesk 1706: const char *
1707: iptos2str(int iptos)
1708: {
1709: int i;
1710: static char iptos_str[sizeof "0xff"];
1711:
1712: for (i = 0; ipqos[i].name != NULL; i++) {
1713: if (ipqos[i].value == iptos)
1714: return ipqos[i].name;
1715: }
1716: snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos);
1717: return iptos_str;
1.92 djm 1718: }
1719:
1720: void
1721: lowercase(char *s)
1722: {
1723: for (; *s; s++)
1724: *s = tolower((u_char)*s);
1.94 millert 1725: }
1726:
1727: int
1728: unix_listener(const char *path, int backlog, int unlink_first)
1729: {
1730: struct sockaddr_un sunaddr;
1731: int saved_errno, sock;
1732:
1733: memset(&sunaddr, 0, sizeof(sunaddr));
1734: sunaddr.sun_family = AF_UNIX;
1.121 djm 1735: if (strlcpy(sunaddr.sun_path, path,
1736: sizeof(sunaddr.sun_path)) >= sizeof(sunaddr.sun_path)) {
1.155 djm 1737: error_f("path \"%s\" too long for Unix domain socket", path);
1.94 millert 1738: errno = ENAMETOOLONG;
1739: return -1;
1740: }
1741:
1742: sock = socket(PF_UNIX, SOCK_STREAM, 0);
1.139 deraadt 1743: if (sock == -1) {
1.94 millert 1744: saved_errno = errno;
1.155 djm 1745: error_f("socket: %.100s", strerror(errno));
1.94 millert 1746: errno = saved_errno;
1747: return -1;
1748: }
1749: if (unlink_first == 1) {
1750: if (unlink(path) != 0 && errno != ENOENT)
1751: error("unlink(%s): %.100s", path, strerror(errno));
1752: }
1.139 deraadt 1753: if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) == -1) {
1.94 millert 1754: saved_errno = errno;
1.155 djm 1755: error_f("cannot bind to path %s: %s", path, strerror(errno));
1.122 djm 1756: close(sock);
1.94 millert 1757: errno = saved_errno;
1758: return -1;
1759: }
1.139 deraadt 1760: if (listen(sock, backlog) == -1) {
1.94 millert 1761: saved_errno = errno;
1.155 djm 1762: error_f("cannot listen on path %s: %s", path, strerror(errno));
1.94 millert 1763: close(sock);
1764: unlink(path);
1765: errno = saved_errno;
1766: return -1;
1767: }
1768: return sock;
1.85 stevesk 1769: }
1.104 djm 1770:
1771: /*
1772: * Compares two strings that maybe be NULL. Returns non-zero if strings
1773: * are both NULL or are identical, returns zero otherwise.
1774: */
1775: static int
1776: strcmp_maybe_null(const char *a, const char *b)
1777: {
1778: if ((a == NULL && b != NULL) || (a != NULL && b == NULL))
1779: return 0;
1780: if (a != NULL && strcmp(a, b) != 0)
1781: return 0;
1782: return 1;
1783: }
1784:
1785: /*
1786: * Compare two forwards, returning non-zero if they are identical or
1787: * zero otherwise.
1788: */
1789: int
1790: forward_equals(const struct Forward *a, const struct Forward *b)
1791: {
1792: if (strcmp_maybe_null(a->listen_host, b->listen_host) == 0)
1793: return 0;
1794: if (a->listen_port != b->listen_port)
1795: return 0;
1796: if (strcmp_maybe_null(a->listen_path, b->listen_path) == 0)
1797: return 0;
1798: if (strcmp_maybe_null(a->connect_host, b->connect_host) == 0)
1799: return 0;
1800: if (a->connect_port != b->connect_port)
1801: return 0;
1802: if (strcmp_maybe_null(a->connect_path, b->connect_path) == 0)
1803: return 0;
1804: /* allocated_port and handle are not checked */
1.107 dtucker 1805: return 1;
1806: }
1807:
1808: /* returns 1 if process is already daemonized, 0 otherwise */
1809: int
1810: daemonized(void)
1811: {
1812: int fd;
1813:
1814: if ((fd = open(_PATH_TTY, O_RDONLY | O_NOCTTY)) >= 0) {
1815: close(fd);
1816: return 0; /* have controlling terminal */
1817: }
1818: if (getppid() != 1)
1819: return 0; /* parent is not init */
1820: if (getsid(0) != getpid())
1821: return 0; /* not session leader */
1822: debug3("already daemonized");
1.106 dtucker 1823: return 1;
1824: }
1.112 djm 1825:
1826:
1827: /*
1828: * Splits 's' into an argument vector. Handles quoted string and basic
1829: * escape characters (\\, \", \'). Caller must free the argument vector
1830: * and its members.
1831: */
1832: int
1833: argv_split(const char *s, int *argcp, char ***argvp)
1834: {
1835: int r = SSH_ERR_INTERNAL_ERROR;
1836: int argc = 0, quote, i, j;
1837: char *arg, **argv = xcalloc(1, sizeof(*argv));
1838:
1839: *argvp = NULL;
1840: *argcp = 0;
1841:
1842: for (i = 0; s[i] != '\0'; i++) {
1843: /* Skip leading whitespace */
1844: if (s[i] == ' ' || s[i] == '\t')
1845: continue;
1846:
1847: /* Start of a token */
1848: quote = 0;
1849: if (s[i] == '\\' &&
1850: (s[i + 1] == '\'' || s[i + 1] == '\"' || s[i + 1] == '\\'))
1851: i++;
1852: else if (s[i] == '\'' || s[i] == '"')
1853: quote = s[i++];
1854:
1855: argv = xreallocarray(argv, (argc + 2), sizeof(*argv));
1856: arg = argv[argc++] = xcalloc(1, strlen(s + i) + 1);
1857: argv[argc] = NULL;
1858:
1859: /* Copy the token in, removing escapes */
1860: for (j = 0; s[i] != '\0'; i++) {
1861: if (s[i] == '\\') {
1862: if (s[i + 1] == '\'' ||
1863: s[i + 1] == '\"' ||
1864: s[i + 1] == '\\') {
1865: i++; /* Skip '\' */
1866: arg[j++] = s[i];
1867: } else {
1868: /* Unrecognised escape */
1869: arg[j++] = s[i];
1870: }
1871: } else if (quote == 0 && (s[i] == ' ' || s[i] == '\t'))
1872: break; /* done */
1873: else if (quote != 0 && s[i] == quote)
1874: break; /* done */
1875: else
1876: arg[j++] = s[i];
1877: }
1878: if (s[i] == '\0') {
1879: if (quote != 0) {
1880: /* Ran out of string looking for close quote */
1881: r = SSH_ERR_INVALID_FORMAT;
1882: goto out;
1883: }
1884: break;
1885: }
1886: }
1887: /* Success */
1888: *argcp = argc;
1889: *argvp = argv;
1890: argc = 0;
1891: argv = NULL;
1892: r = 0;
1893: out:
1894: if (argc != 0 && argv != NULL) {
1895: for (i = 0; i < argc; i++)
1896: free(argv[i]);
1897: free(argv);
1898: }
1899: return r;
1900: }
1901:
1902: /*
1903: * Reassemble an argument vector into a string, quoting and escaping as
1904: * necessary. Caller must free returned string.
1905: */
1906: char *
1907: argv_assemble(int argc, char **argv)
1908: {
1909: int i, j, ws, r;
1910: char c, *ret;
1911: struct sshbuf *buf, *arg;
1912:
1913: if ((buf = sshbuf_new()) == NULL || (arg = sshbuf_new()) == NULL)
1.155 djm 1914: fatal_f("sshbuf_new failed");
1.112 djm 1915:
1916: for (i = 0; i < argc; i++) {
1917: ws = 0;
1918: sshbuf_reset(arg);
1919: for (j = 0; argv[i][j] != '\0'; j++) {
1920: r = 0;
1921: c = argv[i][j];
1922: switch (c) {
1923: case ' ':
1924: case '\t':
1925: ws = 1;
1926: r = sshbuf_put_u8(arg, c);
1927: break;
1928: case '\\':
1929: case '\'':
1930: case '"':
1931: if ((r = sshbuf_put_u8(arg, '\\')) != 0)
1932: break;
1933: /* FALLTHROUGH */
1934: default:
1935: r = sshbuf_put_u8(arg, c);
1936: break;
1937: }
1938: if (r != 0)
1.155 djm 1939: fatal_fr(r, "sshbuf_put_u8");
1.112 djm 1940: }
1941: if ((i != 0 && (r = sshbuf_put_u8(buf, ' ')) != 0) ||
1942: (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0) ||
1943: (r = sshbuf_putb(buf, arg)) != 0 ||
1944: (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0))
1.155 djm 1945: fatal_fr(r, "assemble");
1.112 djm 1946: }
1947: if ((ret = malloc(sshbuf_len(buf) + 1)) == NULL)
1.155 djm 1948: fatal_f("malloc failed");
1.112 djm 1949: memcpy(ret, sshbuf_ptr(buf), sshbuf_len(buf));
1950: ret[sshbuf_len(buf)] = '\0';
1951: sshbuf_free(buf);
1952: sshbuf_free(arg);
1953: return ret;
1954: }
1955:
1956: /* Returns 0 if pid exited cleanly, non-zero otherwise */
1957: int
1.113 djm 1958: exited_cleanly(pid_t pid, const char *tag, const char *cmd, int quiet)
1.112 djm 1959: {
1960: int status;
1961:
1962: while (waitpid(pid, &status, 0) == -1) {
1963: if (errno != EINTR) {
1.155 djm 1964: error("%s waitpid: %s", tag, strerror(errno));
1.112 djm 1965: return -1;
1966: }
1967: }
1968: if (WIFSIGNALED(status)) {
1969: error("%s %s exited on signal %d", tag, cmd, WTERMSIG(status));
1970: return -1;
1971: } else if (WEXITSTATUS(status) != 0) {
1.113 djm 1972: do_log2(quiet ? SYSLOG_LEVEL_DEBUG1 : SYSLOG_LEVEL_INFO,
1973: "%s %s failed, status %d", tag, cmd, WEXITSTATUS(status));
1.112 djm 1974: return -1;
1975: }
1976: return 0;
1977: }
1978:
1979: /*
1980: * Check a given path for security. This is defined as all components
1981: * of the path to the file must be owned by either the owner of
1982: * of the file or root and no directories must be group or world writable.
1983: *
1984: * XXX Should any specific check be done for sym links ?
1985: *
1986: * Takes a file name, its stat information (preferably from fstat() to
1987: * avoid races), the uid of the expected owner, their home directory and an
1988: * error buffer plus max size as arguments.
1989: *
1990: * Returns 0 on success and -1 on failure
1991: */
1992: int
1993: safe_path(const char *name, struct stat *stp, const char *pw_dir,
1994: uid_t uid, char *err, size_t errlen)
1995: {
1996: char buf[PATH_MAX], homedir[PATH_MAX];
1997: char *cp;
1998: int comparehome = 0;
1999: struct stat st;
2000:
2001: if (realpath(name, buf) == NULL) {
2002: snprintf(err, errlen, "realpath %s failed: %s", name,
2003: strerror(errno));
2004: return -1;
2005: }
2006: if (pw_dir != NULL && realpath(pw_dir, homedir) != NULL)
2007: comparehome = 1;
2008:
2009: if (!S_ISREG(stp->st_mode)) {
2010: snprintf(err, errlen, "%s is not a regular file", buf);
2011: return -1;
2012: }
2013: if ((stp->st_uid != 0 && stp->st_uid != uid) ||
2014: (stp->st_mode & 022) != 0) {
2015: snprintf(err, errlen, "bad ownership or modes for file %s",
2016: buf);
2017: return -1;
2018: }
2019:
2020: /* for each component of the canonical path, walking upwards */
2021: for (;;) {
2022: if ((cp = dirname(buf)) == NULL) {
2023: snprintf(err, errlen, "dirname() failed");
2024: return -1;
2025: }
2026: strlcpy(buf, cp, sizeof(buf));
2027:
1.139 deraadt 2028: if (stat(buf, &st) == -1 ||
1.112 djm 2029: (st.st_uid != 0 && st.st_uid != uid) ||
2030: (st.st_mode & 022) != 0) {
2031: snprintf(err, errlen,
2032: "bad ownership or modes for directory %s", buf);
2033: return -1;
2034: }
2035:
2036: /* If are past the homedir then we can stop */
2037: if (comparehome && strcmp(homedir, buf) == 0)
2038: break;
2039:
2040: /*
2041: * dirname should always complete with a "/" path,
2042: * but we can be paranoid and check for "." too
2043: */
2044: if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0))
2045: break;
2046: }
2047: return 0;
2048: }
2049:
2050: /*
2051: * Version of safe_path() that accepts an open file descriptor to
2052: * avoid races.
2053: *
2054: * Returns 0 on success and -1 on failure
2055: */
2056: int
2057: safe_path_fd(int fd, const char *file, struct passwd *pw,
2058: char *err, size_t errlen)
2059: {
2060: struct stat st;
2061:
2062: /* check the open file to avoid races */
1.139 deraadt 2063: if (fstat(fd, &st) == -1) {
1.112 djm 2064: snprintf(err, errlen, "cannot stat file %s: %s",
2065: file, strerror(errno));
2066: return -1;
2067: }
2068: return safe_path(file, &st, pw->pw_dir, pw->pw_uid, err, errlen);
2069: }
2070:
2071: /*
2072: * Sets the value of the given variable in the environment. If the variable
2073: * already exists, its value is overridden.
2074: */
2075: void
2076: child_set_env(char ***envp, u_int *envsizep, const char *name,
2077: const char *value)
2078: {
2079: char **env;
2080: u_int envsize;
2081: u_int i, namelen;
2082:
2083: if (strchr(name, '=') != NULL) {
2084: error("Invalid environment variable \"%.100s\"", name);
2085: return;
2086: }
2087:
2088: /*
2089: * Find the slot where the value should be stored. If the variable
2090: * already exists, we reuse the slot; otherwise we append a new slot
2091: * at the end of the array, expanding if necessary.
2092: */
2093: env = *envp;
2094: namelen = strlen(name);
2095: for (i = 0; env[i]; i++)
2096: if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
2097: break;
2098: if (env[i]) {
2099: /* Reuse the slot. */
2100: free(env[i]);
2101: } else {
2102: /* New variable. Expand if necessary. */
2103: envsize = *envsizep;
2104: if (i >= envsize - 1) {
2105: if (envsize >= 1000)
2106: fatal("child_set_env: too many env vars");
2107: envsize += 50;
2108: env = (*envp) = xreallocarray(env, envsize, sizeof(char *));
2109: *envsizep = envsize;
2110: }
2111: /* Need to set the NULL pointer at end of array beyond the new slot. */
2112: env[i + 1] = NULL;
2113: }
2114:
2115: /* Allocate space and format the variable in the appropriate slot. */
1.125 djm 2116: /* XXX xasprintf */
1.112 djm 2117: env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
2118: snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
2119: }
2120:
1.114 millert 2121: /*
2122: * Check and optionally lowercase a domain name, also removes trailing '.'
2123: * Returns 1 on success and 0 on failure, storing an error message in errstr.
2124: */
2125: int
2126: valid_domain(char *name, int makelower, const char **errstr)
2127: {
2128: size_t i, l = strlen(name);
2129: u_char c, last = '\0';
2130: static char errbuf[256];
2131:
2132: if (l == 0) {
2133: strlcpy(errbuf, "empty domain name", sizeof(errbuf));
2134: goto bad;
2135: }
2136: if (!isalpha((u_char)name[0]) && !isdigit((u_char)name[0])) {
2137: snprintf(errbuf, sizeof(errbuf), "domain name \"%.100s\" "
2138: "starts with invalid character", name);
2139: goto bad;
2140: }
2141: for (i = 0; i < l; i++) {
2142: c = tolower((u_char)name[i]);
2143: if (makelower)
2144: name[i] = (char)c;
2145: if (last == '.' && c == '.') {
2146: snprintf(errbuf, sizeof(errbuf), "domain name "
2147: "\"%.100s\" contains consecutive separators", name);
2148: goto bad;
2149: }
2150: if (c != '.' && c != '-' && !isalnum(c) &&
2151: c != '_') /* technically invalid, but common */ {
2152: snprintf(errbuf, sizeof(errbuf), "domain name "
2153: "\"%.100s\" contains invalid characters", name);
2154: goto bad;
2155: }
2156: last = c;
2157: }
2158: if (name[l - 1] == '.')
2159: name[l - 1] = '\0';
2160: if (errstr != NULL)
2161: *errstr = NULL;
2162: return 1;
2163: bad:
2164: if (errstr != NULL)
2165: *errstr = errbuf;
2166: return 0;
1.132 djm 2167: }
2168:
2169: /*
2170: * Verify that a environment variable name (not including initial '$') is
2171: * valid; consisting of one or more alphanumeric or underscore characters only.
2172: * Returns 1 on valid, 0 otherwise.
2173: */
2174: int
2175: valid_env_name(const char *name)
2176: {
2177: const char *cp;
2178:
2179: if (name[0] == '\0')
2180: return 0;
2181: for (cp = name; *cp != '\0'; cp++) {
2182: if (!isalnum((u_char)*cp) && *cp != '_')
2183: return 0;
2184: }
2185: return 1;
1.120 dtucker 2186: }
2187:
2188: const char *
2189: atoi_err(const char *nptr, int *val)
2190: {
2191: const char *errstr = NULL;
2192: long long num;
2193:
2194: if (nptr == NULL || *nptr == '\0')
2195: return "missing";
2196: num = strtonum(nptr, 0, INT_MAX, &errstr);
2197: if (errstr == NULL)
2198: *val = (int)num;
2199: return errstr;
1.127 djm 2200: }
2201:
2202: int
2203: parse_absolute_time(const char *s, uint64_t *tp)
2204: {
2205: struct tm tm;
2206: time_t tt;
2207: char buf[32], *fmt;
2208:
2209: *tp = 0;
2210:
2211: /*
2212: * POSIX strptime says "The application shall ensure that there
2213: * is white-space or other non-alphanumeric characters between
2214: * any two conversion specifications" so arrange things this way.
2215: */
2216: switch (strlen(s)) {
2217: case 8: /* YYYYMMDD */
2218: fmt = "%Y-%m-%d";
2219: snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2s", s, s + 4, s + 6);
2220: break;
2221: case 12: /* YYYYMMDDHHMM */
2222: fmt = "%Y-%m-%dT%H:%M";
2223: snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s",
2224: s, s + 4, s + 6, s + 8, s + 10);
2225: break;
2226: case 14: /* YYYYMMDDHHMMSS */
2227: fmt = "%Y-%m-%dT%H:%M:%S";
2228: snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s:%.2s",
2229: s, s + 4, s + 6, s + 8, s + 10, s + 12);
2230: break;
2231: default:
2232: return SSH_ERR_INVALID_FORMAT;
2233: }
2234:
2235: memset(&tm, 0, sizeof(tm));
2236: if (strptime(buf, fmt, &tm) == NULL)
2237: return SSH_ERR_INVALID_FORMAT;
2238: if ((tt = mktime(&tm)) < 0)
2239: return SSH_ERR_INVALID_FORMAT;
2240: /* success */
2241: *tp = (uint64_t)tt;
2242: return 0;
2243: }
2244:
2245: void
2246: format_absolute_time(uint64_t t, char *buf, size_t len)
2247: {
2248: time_t tt = t > INT_MAX ? INT_MAX : t; /* XXX revisit in 2038 :P */
2249: struct tm tm;
2250:
2251: localtime_r(&tt, &tm);
2252: strftime(buf, len, "%Y-%m-%dT%H:%M:%S", &tm);
1.134 djm 2253: }
2254:
2255: /* check if path is absolute */
2256: int
2257: path_absolute(const char *path)
2258: {
2259: return (*path == '/') ? 1 : 0;
1.141 djm 2260: }
2261:
2262: void
2263: skip_space(char **cpp)
2264: {
2265: char *cp;
2266:
2267: for (cp = *cpp; *cp == ' ' || *cp == '\t'; cp++)
2268: ;
2269: *cpp = cp;
1.114 millert 2270: }
1.142 djm 2271:
2272: /* authorized_key-style options parsing helpers */
2273:
2274: /*
2275: * Match flag 'opt' in *optsp, and if allow_negate is set then also match
2276: * 'no-opt'. Returns -1 if option not matched, 1 if option matches or 0
2277: * if negated option matches.
2278: * If the option or negated option matches, then *optsp is updated to
2279: * point to the first character after the option.
2280: */
2281: int
2282: opt_flag(const char *opt, int allow_negate, const char **optsp)
2283: {
2284: size_t opt_len = strlen(opt);
2285: const char *opts = *optsp;
2286: int negate = 0;
2287:
2288: if (allow_negate && strncasecmp(opts, "no-", 3) == 0) {
2289: opts += 3;
2290: negate = 1;
2291: }
2292: if (strncasecmp(opts, opt, opt_len) == 0) {
2293: *optsp = opts + opt_len;
2294: return negate ? 0 : 1;
2295: }
2296: return -1;
2297: }
2298:
2299: char *
2300: opt_dequote(const char **sp, const char **errstrp)
2301: {
2302: const char *s = *sp;
2303: char *ret;
2304: size_t i;
2305:
2306: *errstrp = NULL;
2307: if (*s != '"') {
2308: *errstrp = "missing start quote";
2309: return NULL;
2310: }
2311: s++;
2312: if ((ret = malloc(strlen((s)) + 1)) == NULL) {
2313: *errstrp = "memory allocation failed";
2314: return NULL;
2315: }
2316: for (i = 0; *s != '\0' && *s != '"';) {
2317: if (s[0] == '\\' && s[1] == '"')
2318: s++;
2319: ret[i++] = *s++;
2320: }
2321: if (*s == '\0') {
2322: *errstrp = "missing end quote";
2323: free(ret);
2324: return NULL;
2325: }
2326: ret[i] = '\0';
2327: s++;
2328: *sp = s;
2329: return ret;
2330: }
2331:
2332: int
2333: opt_match(const char **opts, const char *term)
2334: {
2335: if (strncasecmp((*opts), term, strlen(term)) == 0 &&
2336: (*opts)[strlen(term)] == '=') {
2337: *opts += strlen(term) + 1;
2338: return 1;
2339: }
2340: return 0;
1.161 markus 2341: }
2342:
2343: void
2344: opt_array_append2(const char *file, const int line, const char *directive,
2345: char ***array, int **iarray, u_int *lp, const char *s, int i)
2346: {
2347:
2348: if (*lp >= INT_MAX)
2349: fatal("%s line %d: Too many %s entries", file, line, directive);
2350:
2351: if (iarray != NULL) {
2352: *iarray = xrecallocarray(*iarray, *lp, *lp + 1,
2353: sizeof(**iarray));
2354: (*iarray)[*lp] = i;
2355: }
2356:
2357: *array = xrecallocarray(*array, *lp, *lp + 1, sizeof(**array));
2358: (*array)[*lp] = xstrdup(s);
2359: (*lp)++;
2360: }
2361:
2362: void
2363: opt_array_append(const char *file, const int line, const char *directive,
2364: char ***array, u_int *lp, const char *s)
2365: {
2366: opt_array_append2(file, line, directive, array, NULL, lp, s, 0);
1.142 djm 2367: }
2368:
1.144 dtucker 2369: sshsig_t
2370: ssh_signal(int signum, sshsig_t handler)
2371: {
2372: struct sigaction sa, osa;
2373:
2374: /* mask all other signals while in handler */
1.147 dtucker 2375: memset(&sa, 0, sizeof(sa));
1.144 dtucker 2376: sa.sa_handler = handler;
2377: sigfillset(&sa.sa_mask);
2378: if (signum != SIGALRM)
2379: sa.sa_flags = SA_RESTART;
2380: if (sigaction(signum, &sa, &osa) == -1) {
2381: debug3("sigaction(%s): %s", strsignal(signum), strerror(errno));
2382: return SIG_ERR;
2383: }
2384: return osa.sa_handler;
1.154 djm 2385: }
2386:
2387: int
2388: stdfd_devnull(int do_stdin, int do_stdout, int do_stderr)
2389: {
2390: int devnull, ret = 0;
2391:
2392: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1.155 djm 2393: error_f("open %s: %s", _PATH_DEVNULL,
1.154 djm 2394: strerror(errno));
2395: return -1;
2396: }
2397: if ((do_stdin && dup2(devnull, STDIN_FILENO) == -1) ||
2398: (do_stdout && dup2(devnull, STDOUT_FILENO) == -1) ||
2399: (do_stderr && dup2(devnull, STDERR_FILENO) == -1)) {
1.155 djm 2400: error_f("dup2: %s", strerror(errno));
1.154 djm 2401: ret = -1;
2402: }
2403: if (devnull > STDERR_FILENO)
2404: close(devnull);
2405: return ret;
1.157 djm 2406: }
2407:
2408: /*
2409: * Runs command in a subprocess with a minimal environment.
2410: * Returns pid on success, 0 on failure.
2411: * The child stdout and stderr maybe captured, left attached or sent to
2412: * /dev/null depending on the contents of flags.
2413: * "tag" is prepended to log messages.
2414: * NB. "command" is only used for logging; the actual command executed is
2415: * av[0].
2416: */
2417: pid_t
2418: subprocess(const char *tag, const char *command,
2419: int ac, char **av, FILE **child, u_int flags,
2420: struct passwd *pw, privdrop_fn *drop_privs, privrestore_fn *restore_privs)
2421: {
2422: FILE *f = NULL;
2423: struct stat st;
2424: int fd, devnull, p[2], i;
2425: pid_t pid;
2426: char *cp, errmsg[512];
2427: u_int nenv = 0;
2428: char **env = NULL;
2429:
2430: /* If dropping privs, then must specify user and restore function */
2431: if (drop_privs != NULL && (pw == NULL || restore_privs == NULL)) {
2432: error("%s: inconsistent arguments", tag); /* XXX fatal? */
2433: return 0;
2434: }
2435: if (pw == NULL && (pw = getpwuid(getuid())) == NULL) {
2436: error("%s: no user for current uid", tag);
2437: return 0;
2438: }
2439: if (child != NULL)
2440: *child = NULL;
2441:
2442: debug3_f("%s command \"%s\" running as %s (flags 0x%x)",
2443: tag, command, pw->pw_name, flags);
2444:
2445: /* Check consistency */
2446: if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
2447: (flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0) {
2448: error_f("inconsistent flags");
2449: return 0;
2450: }
2451: if (((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0) != (child == NULL)) {
2452: error_f("inconsistent flags/output");
2453: return 0;
2454: }
2455:
2456: /*
2457: * If executing an explicit binary, then verify the it exists
2458: * and appears safe-ish to execute
2459: */
2460: if (!path_absolute(av[0])) {
2461: error("%s path is not absolute", tag);
2462: return 0;
2463: }
2464: if (drop_privs != NULL)
2465: drop_privs(pw);
2466: if (stat(av[0], &st) == -1) {
2467: error("Could not stat %s \"%s\": %s", tag,
2468: av[0], strerror(errno));
2469: goto restore_return;
2470: }
2471: if ((flags & SSH_SUBPROCESS_UNSAFE_PATH) == 0 &&
2472: safe_path(av[0], &st, NULL, 0, errmsg, sizeof(errmsg)) != 0) {
2473: error("Unsafe %s \"%s\": %s", tag, av[0], errmsg);
2474: goto restore_return;
2475: }
2476: /* Prepare to keep the child's stdout if requested */
2477: if (pipe(p) == -1) {
2478: error("%s: pipe: %s", tag, strerror(errno));
2479: restore_return:
2480: if (restore_privs != NULL)
2481: restore_privs();
2482: return 0;
2483: }
2484: if (restore_privs != NULL)
2485: restore_privs();
2486:
2487: switch ((pid = fork())) {
2488: case -1: /* error */
2489: error("%s: fork: %s", tag, strerror(errno));
2490: close(p[0]);
2491: close(p[1]);
2492: return 0;
2493: case 0: /* child */
2494: /* Prepare a minimal environment for the child. */
2495: if ((flags & SSH_SUBPROCESS_PRESERVE_ENV) == 0) {
2496: nenv = 5;
2497: env = xcalloc(sizeof(*env), nenv);
2498: child_set_env(&env, &nenv, "PATH", _PATH_STDPATH);
2499: child_set_env(&env, &nenv, "USER", pw->pw_name);
2500: child_set_env(&env, &nenv, "LOGNAME", pw->pw_name);
2501: child_set_env(&env, &nenv, "HOME", pw->pw_dir);
2502: if ((cp = getenv("LANG")) != NULL)
2503: child_set_env(&env, &nenv, "LANG", cp);
2504: }
2505:
1.162 ! dtucker 2506: for (i = 1; i < NSIG; i++)
1.157 djm 2507: ssh_signal(i, SIG_DFL);
2508:
2509: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
2510: error("%s: open %s: %s", tag, _PATH_DEVNULL,
2511: strerror(errno));
2512: _exit(1);
2513: }
2514: if (dup2(devnull, STDIN_FILENO) == -1) {
2515: error("%s: dup2: %s", tag, strerror(errno));
2516: _exit(1);
2517: }
2518:
2519: /* Set up stdout as requested; leave stderr in place for now. */
2520: fd = -1;
2521: if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0)
2522: fd = p[1];
2523: else if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0)
2524: fd = devnull;
2525: if (fd != -1 && dup2(fd, STDOUT_FILENO) == -1) {
2526: error("%s: dup2: %s", tag, strerror(errno));
2527: _exit(1);
2528: }
2529: closefrom(STDERR_FILENO + 1);
2530:
2531: if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) {
2532: error("%s: setresgid %u: %s", tag, (u_int)pw->pw_gid,
2533: strerror(errno));
2534: _exit(1);
2535: }
2536: if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1) {
2537: error("%s: setresuid %u: %s", tag, (u_int)pw->pw_uid,
2538: strerror(errno));
2539: _exit(1);
2540: }
2541: /* stdin is pointed to /dev/null at this point */
2542: if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
2543: dup2(STDIN_FILENO, STDERR_FILENO) == -1) {
2544: error("%s: dup2: %s", tag, strerror(errno));
2545: _exit(1);
2546: }
2547: if (env != NULL)
2548: execve(av[0], av, env);
2549: else
2550: execv(av[0], av);
2551: error("%s %s \"%s\": %s", tag, env == NULL ? "execv" : "execve",
2552: command, strerror(errno));
2553: _exit(127);
2554: default: /* parent */
2555: break;
2556: }
2557:
2558: close(p[1]);
2559: if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0)
2560: close(p[0]);
2561: else if ((f = fdopen(p[0], "r")) == NULL) {
2562: error("%s: fdopen: %s", tag, strerror(errno));
2563: close(p[0]);
2564: /* Don't leave zombie child */
2565: kill(pid, SIGTERM);
2566: while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
2567: ;
2568: return 0;
2569: }
2570: /* Success */
2571: debug3_f("%s pid %ld", tag, (long)pid);
2572: if (child != NULL)
2573: *child = f;
2574: return pid;
1.144 dtucker 2575: }
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