1 /* $OpenBSD: misc.c,v 1.169 2021/08/09 23:47:44 djm Exp $ */
3 * Copyright (c) 2000 Markus Friedl. All rights reserved.
4 * Copyright (c) 2005-2020 Damien Miller. All rights reserved.
5 * Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
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.
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.
23 #include <sys/types.h>
24 #include <sys/ioctl.h>
25 #include <sys/socket.h>
46 #include <netinet/in.h>
47 #include <netinet/in_systm.h>
48 #include <netinet/ip.h>
49 #include <netinet/tcp.h>
50 #include <arpa/inet.h>
60 #ifdef SSH_TUN_OPENBSD
72 /* remove newline at end of string */
78 if (*t == '\n' || *t == '\r') {
88 /* remove whitespace from end of string */
94 if ((i = strlen(s)) == 0)
96 for (i--; i > 0; i--) {
97 if (isspace((int)s[i]))
102 /* set/unset filedescriptor to non-blocking */
108 val = fcntl(fd, F_GETFL);
110 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno));
113 if (val & O_NONBLOCK) {
114 debug3("fd %d is O_NONBLOCK", fd);
117 debug2("fd %d setting O_NONBLOCK", fd);
119 if (fcntl(fd, F_SETFL, val) == -1) {
120 debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
128 unset_nonblock(int fd)
132 val = fcntl(fd, F_GETFL);
134 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno));
137 if (!(val & O_NONBLOCK)) {
138 debug3("fd %d is not O_NONBLOCK", fd);
141 debug("fd %d clearing O_NONBLOCK", fd);
143 if (fcntl(fd, F_SETFL, val) == -1) {
144 debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
145 fd, strerror(errno));
152 ssh_gai_strerror(int gaierr)
154 if (gaierr == EAI_SYSTEM && errno != 0)
155 return strerror(errno);
156 return gai_strerror(gaierr);
159 /* disable nagle on socket */
167 if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
168 debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
172 debug2("fd %d is TCP_NODELAY", fd);
176 debug2("fd %d setting TCP_NODELAY", fd);
177 if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
178 error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
181 /* Allow local port reuse in TIME_WAIT */
183 set_reuseaddr(int fd)
187 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) {
188 error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
194 /* Get/set routing domain */
198 #if defined(HAVE_SYS_GET_RDOMAIN)
199 return sys_get_rdomain(fd);
200 #elif defined(__OpenBSD__)
203 socklen_t len = sizeof(rtable);
205 if (getsockopt(fd, SOL_SOCKET, SO_RTABLE, &rtable, &len) == -1) {
206 error("Failed to get routing domain for fd %d: %s",
207 fd, strerror(errno));
210 xasprintf(&ret, "%d", rtable);
212 #else /* defined(__OpenBSD__) */
218 set_rdomain(int fd, const char *name)
220 #if defined(HAVE_SYS_SET_RDOMAIN)
221 return sys_set_rdomain(fd, name);
222 #elif defined(__OpenBSD__)
227 return 0; /* default table */
229 rtable = (int)strtonum(name, 0, 255, &errstr);
230 if (errstr != NULL) {
231 /* Shouldn't happen */
232 error("Invalid routing domain \"%s\": %s", name, errstr);
235 if (setsockopt(fd, SOL_SOCKET, SO_RTABLE,
236 &rtable, sizeof(rtable)) == -1) {
237 error("Failed to set routing domain %d on fd %d: %s",
238 rtable, fd, strerror(errno));
242 #else /* defined(__OpenBSD__) */
243 error("Setting routing domain is not supported on this platform");
251 struct sockaddr_storage to;
252 socklen_t tolen = sizeof(to);
254 memset(&to, 0, sizeof(to));
255 if (getsockname(fd, (struct sockaddr *)&to, &tolen) == -1)
258 if (to.ss_family == AF_INET6 &&
259 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
266 set_sock_tos(int fd, int tos)
268 #ifndef IP_TOS_IS_BROKEN
271 switch ((af = get_sock_af(fd))) {
273 /* assume not a socket */
277 debug3_f("set socket %d IP_TOS 0x%02x", fd, tos);
278 if (setsockopt(fd, IPPROTO_IP, IP_TOS,
279 &tos, sizeof(tos)) == -1) {
280 error("setsockopt socket %d IP_TOS %d: %s:",
281 fd, tos, strerror(errno));
287 debug3_f("set socket %d IPV6_TCLASS 0x%02x", fd, tos);
288 if (setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS,
289 &tos, sizeof(tos)) == -1) {
290 error("setsockopt socket %d IPV6_TCLASS %d: %.100s:",
291 fd, tos, strerror(errno));
293 # endif /* IPV6_TCLASS */
296 debug2_f("unsupported socket family %d", af);
299 #endif /* IP_TOS_IS_BROKEN */
303 * Wait up to *timeoutp milliseconds for events on fd. Updates
304 * *timeoutp with time remaining.
305 * Returns 0 if fd ready or -1 on timeout or error (see errno).
308 waitfd(int fd, int *timeoutp, short events)
311 struct timeval t_start;
316 for (; *timeoutp >= 0;) {
317 monotime_tv(&t_start);
318 r = poll(&pfd, 1, *timeoutp);
320 ms_subtract_diff(&t_start, timeoutp);
324 else if (r == -1 && errno != EAGAIN && errno != EINTR)
335 * Wait up to *timeoutp milliseconds for fd to be readable. Updates
336 * *timeoutp with time remaining.
337 * Returns 0 if fd ready or -1 on timeout or error (see errno).
340 waitrfd(int fd, int *timeoutp) {
341 return waitfd(fd, timeoutp, POLLIN);
345 * Attempt a non-blocking connect(2) to the specified address, waiting up to
346 * *timeoutp milliseconds for the connection to complete. If the timeout is
347 * <=0, then wait indefinitely.
349 * Returns 0 on success or -1 on failure.
352 timeout_connect(int sockfd, const struct sockaddr *serv_addr,
353 socklen_t addrlen, int *timeoutp)
356 socklen_t optlen = sizeof(optval);
358 /* No timeout: just do a blocking connect() */
359 if (timeoutp == NULL || *timeoutp <= 0)
360 return connect(sockfd, serv_addr, addrlen);
362 set_nonblock(sockfd);
364 if (connect(sockfd, serv_addr, addrlen) == 0) {
365 /* Succeeded already? */
366 unset_nonblock(sockfd);
368 } else if (errno == EINTR)
370 else if (errno != EINPROGRESS)
375 if (waitfd(sockfd, timeoutp, POLLIN | POLLOUT) == -1)
378 /* Completed or failed */
379 if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, &optlen) == -1) {
380 debug("getsockopt: %s", strerror(errno));
387 unset_nonblock(sockfd);
391 /* Characters considered whitespace in strsep calls. */
392 #define WHITESPACE " \t\r\n"
395 /* return next token in configuration line */
397 strdelim_internal(char **s, int split_equals)
408 split_equals ? WHITESPACE QUOTE "=" : WHITESPACE QUOTE);
413 memmove(*s, *s + 1, strlen(*s)); /* move nul too */
414 /* Find matching quote */
415 if ((*s = strpbrk(*s, QUOTE)) == NULL) {
416 return (NULL); /* no matching quote */
419 *s += strspn(*s + 1, WHITESPACE) + 1;
424 /* Allow only one '=' to be skipped */
425 if (split_equals && *s[0] == '=')
429 /* Skip any extra whitespace after first token */
430 *s += strspn(*s + 1, WHITESPACE) + 1;
431 if (split_equals && *s[0] == '=' && !wspace)
432 *s += strspn(*s + 1, WHITESPACE) + 1;
438 * Return next token in configuration line; splts on whitespace or a
439 * single '=' character.
444 return strdelim_internal(s, 1);
448 * Return next token in configuration line; splts on whitespace only.
453 return strdelim_internal(s, 0);
457 pwcopy(struct passwd *pw)
459 struct passwd *copy = xcalloc(1, sizeof(*copy));
461 copy->pw_name = xstrdup(pw->pw_name);
462 copy->pw_passwd = xstrdup(pw->pw_passwd == NULL ? "*" : pw->pw_passwd);
463 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS
464 copy->pw_gecos = xstrdup(pw->pw_gecos);
466 copy->pw_uid = pw->pw_uid;
467 copy->pw_gid = pw->pw_gid;
468 #ifdef HAVE_STRUCT_PASSWD_PW_EXPIRE
469 copy->pw_expire = pw->pw_expire;
471 #ifdef HAVE_STRUCT_PASSWD_PW_CHANGE
472 copy->pw_change = pw->pw_change;
474 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS
475 copy->pw_class = xstrdup(pw->pw_class);
477 copy->pw_dir = xstrdup(pw->pw_dir);
478 copy->pw_shell = xstrdup(pw->pw_shell);
483 * Convert ASCII string to TCP/IP port number.
484 * Port must be >=0 and <=65535.
485 * Return -1 if invalid.
488 a2port(const char *s)
494 port = strtonum(s, 0, 65535, &errstr);
497 if ((se = getservbyname(s, "tcp")) != NULL)
498 return ntohs(se->s_port);
503 a2tun(const char *s, int *remote)
505 const char *errstr = NULL;
509 if (remote != NULL) {
510 *remote = SSH_TUNID_ANY;
512 if ((ep = strchr(sp, ':')) == NULL) {
514 return (a2tun(s, NULL));
517 *remote = a2tun(ep, NULL);
518 tun = a2tun(sp, NULL);
520 return (*remote == SSH_TUNID_ERR ? *remote : tun);
523 if (strcasecmp(s, "any") == 0)
524 return (SSH_TUNID_ANY);
526 tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
528 return (SSH_TUNID_ERR);
534 #define MINUTES (SECONDS * 60)
535 #define HOURS (MINUTES * 60)
536 #define DAYS (HOURS * 24)
537 #define WEEKS (DAYS * 7)
540 * Convert a time string into seconds; format is
544 * Valid time qualifiers are:
558 * Return -1 if time string is invalid.
561 convtime(const char *s)
563 long total, secs, multiplier;
571 if (p == NULL || *p == '\0')
575 secs = strtol(p, &endp, 10);
577 (errno == ERANGE && (secs == INT_MIN || secs == INT_MAX)) ||
591 multiplier = MINUTES;
608 if (secs > INT_MAX / multiplier)
611 if (total > INT_MAX - secs)
626 fmt_timeframe(time_t t)
629 static char tfbuf[TF_BUFS][TF_LEN]; /* ring buffer */
631 unsigned int sec, min, hrs, day;
632 unsigned long long week;
650 snprintf(buf, TF_LEN, "%02lluw%01ud%02uh", week, day, hrs);
652 snprintf(buf, TF_LEN, "%01ud%02uh%02um", day, hrs, min);
654 snprintf(buf, TF_LEN, "%02u:%02u:%02u", hrs, min, sec);
660 * Returns a standardized host+port identifier string.
661 * Caller must free returned string.
664 put_host_port(const char *host, u_short port)
668 if (port == 0 || port == SSH_DEFAULT_PORT)
669 return(xstrdup(host));
670 if (asprintf(&hoststr, "[%s]:%d", host, (int)port) == -1)
671 fatal("put_host_port: asprintf: %s", strerror(errno));
672 debug3("put_host_port: %s", hoststr);
677 * Search for next delimiter between hostnames/addresses and ports.
678 * Argument may be modified (for termination).
679 * Returns *cp if parsing succeeds.
680 * *cp is set to the start of the next field, if one was found.
681 * The delimiter char, if present, is stored in delim.
682 * If this is the last field, *cp is set to NULL.
685 hpdelim2(char **cp, char *delim)
689 if (cp == NULL || *cp == NULL)
694 if ((s = strchr(s, ']')) == NULL)
698 } else if ((s = strpbrk(s, ":/")) == NULL)
699 s = *cp + strlen(*cp); /* skip to end (see first case below) */
703 *cp = NULL; /* no more fields*/
710 *s = '\0'; /* terminate */
724 return hpdelim2(cp, NULL);
728 cleanhostname(char *host)
730 if (*host == '[' && host[strlen(host) - 1] == ']') {
731 host[strlen(host) - 1] = '\0';
742 if (*cp == ':') /* Leading colon is part of file name. */
748 if (*cp == '@' && *(cp+1) == '[')
750 if (*cp == ']' && *(cp+1) == ':' && flag)
752 if (*cp == ':' && !flag)
761 * Parse a [user@]host:[path] string.
762 * Caller must free returned user, host and path.
763 * Any of the pointer return arguments may be NULL (useful for syntax checking).
764 * If user was not specified then *userp will be set to NULL.
765 * If host was not specified then *hostp will be set to NULL.
766 * If path was not specified then *pathp will be set to ".".
767 * Returns 0 on success, -1 on failure.
770 parse_user_host_path(const char *s, char **userp, char **hostp, char **pathp)
772 char *user = NULL, *host = NULL, *path = NULL;
785 /* Check for remote syntax: [user@]host:[path] */
786 if ((tmp = colon(sdup)) == NULL)
789 /* Extract optional path */
795 /* Extract optional user and mandatory host */
796 tmp = strrchr(sdup, '@');
799 host = xstrdup(cleanhostname(tmp));
801 user = xstrdup(sdup);
803 host = xstrdup(cleanhostname(sdup));
830 * Parse a [user@]host[:port] string.
831 * Caller must free returned user and host.
832 * Any of the pointer return arguments may be NULL (useful for syntax checking).
833 * If user was not specified then *userp will be set to NULL.
834 * If port was not specified then *portp will be -1.
835 * Returns 0 on success, -1 on failure.
838 parse_user_host_port(const char *s, char **userp, char **hostp, int *portp)
840 char *sdup, *cp, *tmp;
841 char *user = NULL, *host = NULL;
842 int port = -1, ret = -1;
851 if ((sdup = tmp = strdup(s)) == NULL)
853 /* Extract optional username */
854 if ((cp = strrchr(tmp, '@')) != NULL) {
858 if ((user = strdup(tmp)) == NULL)
862 /* Extract mandatory hostname */
863 if ((cp = hpdelim(&tmp)) == NULL || *cp == '\0')
865 host = xstrdup(cleanhostname(cp));
866 /* Convert and verify optional port */
867 if (tmp != NULL && *tmp != '\0') {
868 if ((port = a2port(tmp)) <= 0)
891 * Converts a two-byte hex string to decimal.
892 * Returns the decimal value or -1 for invalid input.
895 hexchar(const char *s)
897 unsigned char result[2];
900 for (i = 0; i < 2; i++) {
901 if (s[i] >= '0' && s[i] <= '9')
902 result[i] = (unsigned char)(s[i] - '0');
903 else if (s[i] >= 'a' && s[i] <= 'f')
904 result[i] = (unsigned char)(s[i] - 'a') + 10;
905 else if (s[i] >= 'A' && s[i] <= 'F')
906 result[i] = (unsigned char)(s[i] - 'A') + 10;
910 return (result[0] << 4) | result[1];
914 * Decode an url-encoded string.
915 * Returns a newly allocated string on success or NULL on failure.
918 urldecode(const char *src)
923 ret = xmalloc(strlen(src) + 1);
924 for (dst = ret; *src != '\0'; src++) {
930 if (!isxdigit((unsigned char)src[1]) ||
931 !isxdigit((unsigned char)src[2]) ||
932 (ch = hexchar(src + 1)) == -1) {
950 * Parse an (scp|ssh|sftp)://[user@]host[:port][/path] URI.
951 * See https://tools.ietf.org/html/draft-ietf-secsh-scp-sftp-ssh-uri-04
952 * Either user or path may be url-encoded (but not host or port).
953 * Caller must free returned user, host and path.
954 * Any of the pointer return arguments may be NULL (useful for syntax checking)
955 * but the scheme must always be specified.
956 * If user was not specified then *userp will be set to NULL.
957 * If port was not specified then *portp will be -1.
958 * If path was not specified then *pathp will be set to NULL.
959 * Returns 0 on success, 1 if non-uri/wrong scheme, -1 on error/invalid uri.
962 parse_uri(const char *scheme, const char *uri, char **userp, char **hostp,
963 int *portp, char **pathp)
965 char *uridup, *cp, *tmp, ch;
966 char *user = NULL, *host = NULL, *path = NULL;
967 int port = -1, ret = -1;
970 len = strlen(scheme);
971 if (strncmp(uri, scheme, len) != 0 || strncmp(uri + len, "://", 3) != 0)
984 uridup = tmp = xstrdup(uri);
986 /* Extract optional ssh-info (username + connection params) */
987 if ((cp = strchr(tmp, '@')) != NULL) {
991 /* Extract username and connection params */
992 if ((delim = strchr(tmp, ';')) != NULL) {
993 /* Just ignore connection params for now */
1000 if ((user = urldecode(tmp)) == NULL)
1005 /* Extract mandatory hostname */
1006 if ((cp = hpdelim2(&tmp, &ch)) == NULL || *cp == '\0')
1008 host = xstrdup(cleanhostname(cp));
1009 if (!valid_domain(host, 0, NULL))
1012 if (tmp != NULL && *tmp != '\0') {
1014 /* Convert and verify port. */
1015 if ((cp = strchr(tmp, '/')) != NULL)
1017 if ((port = a2port(tmp)) <= 0)
1019 tmp = cp ? cp + 1 : NULL;
1021 if (tmp != NULL && *tmp != '\0') {
1022 /* Extract optional path */
1023 if ((path = urldecode(tmp)) == NULL)
1029 if (userp != NULL) {
1033 if (hostp != NULL) {
1039 if (pathp != NULL) {
1052 /* function to assist building execv() arguments */
1054 addargs(arglist *args, char *fmt, ...)
1062 r = vasprintf(&cp, fmt, ap);
1065 fatal("addargs: argument too long");
1067 nalloc = args->nalloc;
1068 if (args->list == NULL) {
1071 } else if (args->num+2 >= nalloc)
1074 args->list = xrecallocarray(args->list, args->nalloc, nalloc, sizeof(char *));
1075 args->nalloc = nalloc;
1076 args->list[args->num++] = cp;
1077 args->list[args->num] = NULL;
1081 replacearg(arglist *args, u_int which, char *fmt, ...)
1088 r = vasprintf(&cp, fmt, ap);
1091 fatal("replacearg: argument too long");
1093 if (which >= args->num)
1094 fatal("replacearg: tried to replace invalid arg %d >= %d",
1096 free(args->list[which]);
1097 args->list[which] = cp;
1101 freeargs(arglist *args)
1105 if (args->list != NULL) {
1106 for (i = 0; i < args->num; i++)
1107 free(args->list[i]);
1109 args->nalloc = args->num = 0;
1115 * Expands tildes in the file name. Returns data allocated by xmalloc.
1116 * Warning: this calls getpw*.
1119 tilde_expand(const char *filename, uid_t uid, char **retp)
1121 const char *path, *sep;
1122 char user[128], *ret;
1126 if (*filename != '~') {
1127 *retp = xstrdup(filename);
1132 path = strchr(filename, '/');
1133 if (path != NULL && path > filename) { /* ~user/path */
1134 slash = path - filename;
1135 if (slash > sizeof(user) - 1) {
1136 error_f("~username too long");
1139 memcpy(user, filename, slash);
1141 if ((pw = getpwnam(user)) == NULL) {
1142 error_f("No such user %s", user);
1145 } else if ((pw = getpwuid(uid)) == NULL) { /* ~/path */
1146 error_f("No such uid %ld", (long)uid);
1150 /* Make sure directory has a trailing '/' */
1151 len = strlen(pw->pw_dir);
1152 if (len == 0 || pw->pw_dir[len - 1] != '/')
1157 /* Skip leading '/' from specified path */
1159 filename = path + 1;
1161 if (xasprintf(&ret, "%s%s%s", pw->pw_dir, sep, filename) >= PATH_MAX) {
1162 error_f("Path too long");
1171 tilde_expand_filename(const char *filename, uid_t uid)
1175 if (tilde_expand(filename, uid, &ret) != 0)
1181 * Expand a string with a set of %[char] escapes and/or ${ENVIRONMENT}
1182 * substitutions. A number of escapes may be specified as
1183 * (char *escape_chars, char *replacement) pairs. The list must be terminated
1184 * by a NULL escape_char. Returns replaced string in memory allocated by
1185 * xmalloc which the caller must free.
1188 vdollar_percent_expand(int *parseerror, int dollar, int percent,
1189 const char *string, va_list ap)
1191 #define EXPAND_MAX_KEYS 16
1192 u_int num_keys = 0, i;
1196 } keys[EXPAND_MAX_KEYS];
1198 int r, missingvar = 0;
1199 char *ret = NULL, *var, *varend, *val;
1202 if ((buf = sshbuf_new()) == NULL)
1203 fatal_f("sshbuf_new failed");
1204 if (parseerror == NULL)
1205 fatal_f("null parseerror arg");
1208 /* Gather keys if we're doing percent expansion. */
1210 for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
1211 keys[num_keys].key = va_arg(ap, char *);
1212 if (keys[num_keys].key == NULL)
1214 keys[num_keys].repl = va_arg(ap, char *);
1215 if (keys[num_keys].repl == NULL) {
1216 fatal_f("NULL replacement for token %s",
1217 keys[num_keys].key);
1220 if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL)
1221 fatal_f("too many keys");
1223 fatal_f("percent expansion without token list");
1227 for (i = 0; *string != '\0'; string++) {
1228 /* Optionally process ${ENVIRONMENT} expansions. */
1229 if (dollar && string[0] == '$' && string[1] == '{') {
1230 string += 2; /* skip over '${' */
1231 if ((varend = strchr(string, '}')) == NULL) {
1232 error_f("environment variable '%s' missing "
1233 "closing '}'", string);
1236 len = varend - string;
1238 error_f("zero-length environment variable");
1241 var = xmalloc(len + 1);
1242 (void)strlcpy(var, string, len + 1);
1243 if ((val = getenv(var)) == NULL) {
1244 error_f("env var ${%s} has no value", var);
1247 debug3_f("expand ${%s} -> '%s'", var, val);
1248 if ((r = sshbuf_put(buf, val, strlen(val))) !=0)
1249 fatal_fr(r, "sshbuf_put ${}");
1257 * Process percent expansions if we have a list of TOKENs.
1258 * If we're not doing percent expansion everything just gets
1261 if (*string != '%' || !percent) {
1263 if ((r = sshbuf_put_u8(buf, *string)) != 0)
1264 fatal_fr(r, "sshbuf_put_u8 %%");
1271 if (*string == '\0') {
1272 error_f("invalid format");
1275 for (i = 0; i < num_keys; i++) {
1276 if (strchr(keys[i].key, *string) != NULL) {
1277 if ((r = sshbuf_put(buf, keys[i].repl,
1278 strlen(keys[i].repl))) != 0)
1279 fatal_fr(r, "sshbuf_put %%-repl");
1283 if (i >= num_keys) {
1284 error_f("unknown key %%%c", *string);
1288 if (!missingvar && (ret = sshbuf_dup_string(buf)) == NULL)
1289 fatal_f("sshbuf_dup_string failed");
1293 return *parseerror ? NULL : ret;
1294 #undef EXPAND_MAX_KEYS
1298 * Expand only environment variables.
1299 * Note that although this function is variadic like the other similar
1300 * functions, any such arguments will be unused.
1304 dollar_expand(int *parseerr, const char *string, ...)
1310 va_start(ap, string);
1311 ret = vdollar_percent_expand(&err, 1, 0, string, ap);
1313 if (parseerr != NULL)
1319 * Returns expanded string or NULL if a specified environment variable is
1320 * not defined, or calls fatal if the string is invalid.
1323 percent_expand(const char *string, ...)
1329 va_start(ap, string);
1330 ret = vdollar_percent_expand(&err, 0, 1, string, ap);
1338 * Returns expanded string or NULL if a specified environment variable is
1339 * not defined, or calls fatal if the string is invalid.
1342 percent_dollar_expand(const char *string, ...)
1348 va_start(ap, string);
1349 ret = vdollar_percent_expand(&err, 1, 1, string, ap);
1357 tun_open(int tun, int mode, char **ifname)
1359 #if defined(CUSTOM_SYS_TUN_OPEN)
1360 return (sys_tun_open(tun, mode, ifname));
1361 #elif defined(SSH_TUN_OPENBSD)
1365 const char *tunbase = "tun";
1370 if (mode == SSH_TUNMODE_ETHERNET)
1373 /* Open the tunnel device */
1374 if (tun <= SSH_TUNID_MAX) {
1375 snprintf(name, sizeof(name), "/dev/%s%d", tunbase, tun);
1376 fd = open(name, O_RDWR);
1377 } else if (tun == SSH_TUNID_ANY) {
1378 for (tun = 100; tun >= 0; tun--) {
1379 snprintf(name, sizeof(name), "/dev/%s%d",
1381 if ((fd = open(name, O_RDWR)) >= 0)
1385 debug_f("invalid tunnel %u", tun);
1390 debug_f("%s open: %s", name, strerror(errno));
1394 debug_f("%s mode %d fd %d", name, mode, fd);
1396 /* Bring interface up if it is not already */
1397 snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d", tunbase, tun);
1398 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
1401 if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) {
1402 debug_f("get interface %s flags: %s", ifr.ifr_name,
1407 if (!(ifr.ifr_flags & IFF_UP)) {
1408 ifr.ifr_flags |= IFF_UP;
1409 if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) {
1410 debug_f("activate interface %s: %s", ifr.ifr_name,
1417 *ifname = xstrdup(ifr.ifr_name);
1429 error("Tunnel interfaces are not supported on this platform");
1435 sanitise_stdfd(void)
1439 if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1440 fprintf(stderr, "Couldn't open /dev/null: %s\n",
1444 while (++dupfd <= STDERR_FILENO) {
1445 /* Only populate closed fds. */
1446 if (fcntl(dupfd, F_GETFL) == -1 && errno == EBADF) {
1447 if (dup2(nullfd, dupfd) == -1) {
1448 fprintf(stderr, "dup2: %s\n", strerror(errno));
1453 if (nullfd > STDERR_FILENO)
1458 tohex(const void *vp, size_t l)
1460 const u_char *p = (const u_char *)vp;
1465 return xstrdup("tohex: length > 65536");
1469 for (i = 0; i < l; i++) {
1470 snprintf(b, sizeof(b), "%02x", p[i]);
1477 * Extend string *sp by the specified format. If *sp is not NULL (or empty),
1478 * then the separator 'sep' will be prepended before the formatted arguments.
1479 * Extended strings are heap allocated.
1482 xextendf(char **sp, const char *sep, const char *fmt, ...)
1488 xvasprintf(&tmp1, fmt, ap);
1491 if (*sp == NULL || **sp == '\0') {
1496 xasprintf(&tmp2, "%s%s%s", *sp, sep == NULL ? "" : sep, tmp1);
1504 get_u64(const void *vp)
1506 const u_char *p = (const u_char *)vp;
1509 v = (u_int64_t)p[0] << 56;
1510 v |= (u_int64_t)p[1] << 48;
1511 v |= (u_int64_t)p[2] << 40;
1512 v |= (u_int64_t)p[3] << 32;
1513 v |= (u_int64_t)p[4] << 24;
1514 v |= (u_int64_t)p[5] << 16;
1515 v |= (u_int64_t)p[6] << 8;
1516 v |= (u_int64_t)p[7];
1522 get_u32(const void *vp)
1524 const u_char *p = (const u_char *)vp;
1527 v = (u_int32_t)p[0] << 24;
1528 v |= (u_int32_t)p[1] << 16;
1529 v |= (u_int32_t)p[2] << 8;
1530 v |= (u_int32_t)p[3];
1536 get_u32_le(const void *vp)
1538 const u_char *p = (const u_char *)vp;
1541 v = (u_int32_t)p[0];
1542 v |= (u_int32_t)p[1] << 8;
1543 v |= (u_int32_t)p[2] << 16;
1544 v |= (u_int32_t)p[3] << 24;
1550 get_u16(const void *vp)
1552 const u_char *p = (const u_char *)vp;
1555 v = (u_int16_t)p[0] << 8;
1556 v |= (u_int16_t)p[1];
1562 put_u64(void *vp, u_int64_t v)
1564 u_char *p = (u_char *)vp;
1566 p[0] = (u_char)(v >> 56) & 0xff;
1567 p[1] = (u_char)(v >> 48) & 0xff;
1568 p[2] = (u_char)(v >> 40) & 0xff;
1569 p[3] = (u_char)(v >> 32) & 0xff;
1570 p[4] = (u_char)(v >> 24) & 0xff;
1571 p[5] = (u_char)(v >> 16) & 0xff;
1572 p[6] = (u_char)(v >> 8) & 0xff;
1573 p[7] = (u_char)v & 0xff;
1577 put_u32(void *vp, u_int32_t v)
1579 u_char *p = (u_char *)vp;
1581 p[0] = (u_char)(v >> 24) & 0xff;
1582 p[1] = (u_char)(v >> 16) & 0xff;
1583 p[2] = (u_char)(v >> 8) & 0xff;
1584 p[3] = (u_char)v & 0xff;
1588 put_u32_le(void *vp, u_int32_t v)
1590 u_char *p = (u_char *)vp;
1592 p[0] = (u_char)v & 0xff;
1593 p[1] = (u_char)(v >> 8) & 0xff;
1594 p[2] = (u_char)(v >> 16) & 0xff;
1595 p[3] = (u_char)(v >> 24) & 0xff;
1599 put_u16(void *vp, u_int16_t v)
1601 u_char *p = (u_char *)vp;
1603 p[0] = (u_char)(v >> 8) & 0xff;
1604 p[1] = (u_char)v & 0xff;
1608 ms_subtract_diff(struct timeval *start, int *ms)
1610 struct timeval diff, finish;
1612 monotime_tv(&finish);
1613 timersub(&finish, start, &diff);
1614 *ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000);
1618 ms_to_timeval(struct timeval *tv, int ms)
1622 tv->tv_sec = ms / 1000;
1623 tv->tv_usec = (ms % 1000) * 1000;
1627 monotime_ts(struct timespec *ts)
1630 #if defined(HAVE_CLOCK_GETTIME) && (defined(CLOCK_BOOTTIME) || \
1631 defined(CLOCK_MONOTONIC) || defined(CLOCK_REALTIME))
1632 static int gettime_failed = 0;
1634 if (!gettime_failed) {
1635 # ifdef CLOCK_BOOTTIME
1636 if (clock_gettime(CLOCK_BOOTTIME, ts) == 0)
1638 # endif /* CLOCK_BOOTTIME */
1639 # ifdef CLOCK_MONOTONIC
1640 if (clock_gettime(CLOCK_MONOTONIC, ts) == 0)
1642 # endif /* CLOCK_MONOTONIC */
1643 # ifdef CLOCK_REALTIME
1644 /* Not monotonic, but we're almost out of options here. */
1645 if (clock_gettime(CLOCK_REALTIME, ts) == 0)
1647 # endif /* CLOCK_REALTIME */
1648 debug3("clock_gettime: %s", strerror(errno));
1651 #endif /* HAVE_CLOCK_GETTIME && (BOOTTIME || MONOTONIC || REALTIME) */
1652 gettimeofday(&tv, NULL);
1653 ts->tv_sec = tv.tv_sec;
1654 ts->tv_nsec = (long)tv.tv_usec * 1000;
1658 monotime_tv(struct timeval *tv)
1663 tv->tv_sec = ts.tv_sec;
1664 tv->tv_usec = ts.tv_nsec / 1000;
1677 monotime_double(void)
1682 return ts.tv_sec + ((double)ts.tv_nsec / 1000000000);
1686 bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen)
1688 bw->buflen = buflen;
1690 bw->thresh = buflen;
1692 timerclear(&bw->bwstart);
1693 timerclear(&bw->bwend);
1696 /* Callback from read/write loop to insert bandwidth-limiting delays */
1698 bandwidth_limit(struct bwlimit *bw, size_t read_len)
1701 struct timespec ts, rm;
1703 bw->lamt += read_len;
1704 if (!timerisset(&bw->bwstart)) {
1705 monotime_tv(&bw->bwstart);
1708 if (bw->lamt < bw->thresh)
1711 monotime_tv(&bw->bwend);
1712 timersub(&bw->bwend, &bw->bwstart, &bw->bwend);
1713 if (!timerisset(&bw->bwend))
1717 waitlen = (double)1000000L * bw->lamt / bw->rate;
1719 bw->bwstart.tv_sec = waitlen / 1000000L;
1720 bw->bwstart.tv_usec = waitlen % 1000000L;
1722 if (timercmp(&bw->bwstart, &bw->bwend, >)) {
1723 timersub(&bw->bwstart, &bw->bwend, &bw->bwend);
1725 /* Adjust the wait time */
1726 if (bw->bwend.tv_sec) {
1728 if (bw->thresh < bw->buflen / 4)
1729 bw->thresh = bw->buflen / 4;
1730 } else if (bw->bwend.tv_usec < 10000) {
1732 if (bw->thresh > bw->buflen * 8)
1733 bw->thresh = bw->buflen * 8;
1736 TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts);
1737 while (nanosleep(&ts, &rm) == -1) {
1745 monotime_tv(&bw->bwstart);
1748 /* Make a template filename for mk[sd]temp() */
1750 mktemp_proto(char *s, size_t len)
1755 if ((tmpdir = getenv("TMPDIR")) != NULL) {
1756 r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir);
1757 if (r > 0 && (size_t)r < len)
1760 r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX");
1761 if (r < 0 || (size_t)r >= len)
1762 fatal_f("template string too short");
1765 static const struct {
1769 { "none", INT_MAX }, /* can't use 0 here; that's CS0 */
1770 { "af11", IPTOS_DSCP_AF11 },
1771 { "af12", IPTOS_DSCP_AF12 },
1772 { "af13", IPTOS_DSCP_AF13 },
1773 { "af21", IPTOS_DSCP_AF21 },
1774 { "af22", IPTOS_DSCP_AF22 },
1775 { "af23", IPTOS_DSCP_AF23 },
1776 { "af31", IPTOS_DSCP_AF31 },
1777 { "af32", IPTOS_DSCP_AF32 },
1778 { "af33", IPTOS_DSCP_AF33 },
1779 { "af41", IPTOS_DSCP_AF41 },
1780 { "af42", IPTOS_DSCP_AF42 },
1781 { "af43", IPTOS_DSCP_AF43 },
1782 { "cs0", IPTOS_DSCP_CS0 },
1783 { "cs1", IPTOS_DSCP_CS1 },
1784 { "cs2", IPTOS_DSCP_CS2 },
1785 { "cs3", IPTOS_DSCP_CS3 },
1786 { "cs4", IPTOS_DSCP_CS4 },
1787 { "cs5", IPTOS_DSCP_CS5 },
1788 { "cs6", IPTOS_DSCP_CS6 },
1789 { "cs7", IPTOS_DSCP_CS7 },
1790 { "ef", IPTOS_DSCP_EF },
1791 { "le", IPTOS_DSCP_LE },
1792 { "lowdelay", IPTOS_LOWDELAY },
1793 { "throughput", IPTOS_THROUGHPUT },
1794 { "reliability", IPTOS_RELIABILITY },
1799 parse_ipqos(const char *cp)
1807 for (i = 0; ipqos[i].name != NULL; i++) {
1808 if (strcasecmp(cp, ipqos[i].name) == 0)
1809 return ipqos[i].value;
1811 /* Try parsing as an integer */
1812 val = strtol(cp, &ep, 0);
1813 if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255)
1819 iptos2str(int iptos)
1822 static char iptos_str[sizeof "0xff"];
1824 for (i = 0; ipqos[i].name != NULL; i++) {
1825 if (ipqos[i].value == iptos)
1826 return ipqos[i].name;
1828 snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos);
1836 *s = tolower((u_char)*s);
1840 unix_listener(const char *path, int backlog, int unlink_first)
1842 struct sockaddr_un sunaddr;
1843 int saved_errno, sock;
1845 memset(&sunaddr, 0, sizeof(sunaddr));
1846 sunaddr.sun_family = AF_UNIX;
1847 if (strlcpy(sunaddr.sun_path, path,
1848 sizeof(sunaddr.sun_path)) >= sizeof(sunaddr.sun_path)) {
1849 error_f("path \"%s\" too long for Unix domain socket", path);
1850 errno = ENAMETOOLONG;
1854 sock = socket(PF_UNIX, SOCK_STREAM, 0);
1856 saved_errno = errno;
1857 error_f("socket: %.100s", strerror(errno));
1858 errno = saved_errno;
1861 if (unlink_first == 1) {
1862 if (unlink(path) != 0 && errno != ENOENT)
1863 error("unlink(%s): %.100s", path, strerror(errno));
1865 if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) == -1) {
1866 saved_errno = errno;
1867 error_f("cannot bind to path %s: %s", path, strerror(errno));
1869 errno = saved_errno;
1872 if (listen(sock, backlog) == -1) {
1873 saved_errno = errno;
1874 error_f("cannot listen on path %s: %s", path, strerror(errno));
1877 errno = saved_errno;
1884 sock_set_v6only(int s)
1886 #if defined(IPV6_V6ONLY) && !defined(__OpenBSD__)
1889 debug3("%s: set socket %d IPV6_V6ONLY", __func__, s);
1890 if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1)
1891 error("setsockopt IPV6_V6ONLY: %s", strerror(errno));
1896 * Compares two strings that maybe be NULL. Returns non-zero if strings
1897 * are both NULL or are identical, returns zero otherwise.
1900 strcmp_maybe_null(const char *a, const char *b)
1902 if ((a == NULL && b != NULL) || (a != NULL && b == NULL))
1904 if (a != NULL && strcmp(a, b) != 0)
1910 * Compare two forwards, returning non-zero if they are identical or
1914 forward_equals(const struct Forward *a, const struct Forward *b)
1916 if (strcmp_maybe_null(a->listen_host, b->listen_host) == 0)
1918 if (a->listen_port != b->listen_port)
1920 if (strcmp_maybe_null(a->listen_path, b->listen_path) == 0)
1922 if (strcmp_maybe_null(a->connect_host, b->connect_host) == 0)
1924 if (a->connect_port != b->connect_port)
1926 if (strcmp_maybe_null(a->connect_path, b->connect_path) == 0)
1928 /* allocated_port and handle are not checked */
1932 /* returns 1 if process is already daemonized, 0 otherwise */
1938 if ((fd = open(_PATH_TTY, O_RDONLY | O_NOCTTY)) >= 0) {
1940 return 0; /* have controlling terminal */
1943 return 0; /* parent is not init */
1944 if (getsid(0) != getpid())
1945 return 0; /* not session leader */
1946 debug3("already daemonized");
1951 * Splits 's' into an argument vector. Handles quoted string and basic
1952 * escape characters (\\, \", \'). Caller must free the argument vector
1956 argv_split(const char *s, int *argcp, char ***argvp, int terminate_on_comment)
1958 int r = SSH_ERR_INTERNAL_ERROR;
1959 int argc = 0, quote, i, j;
1960 char *arg, **argv = xcalloc(1, sizeof(*argv));
1965 for (i = 0; s[i] != '\0'; i++) {
1966 /* Skip leading whitespace */
1967 if (s[i] == ' ' || s[i] == '\t')
1969 if (terminate_on_comment && s[i] == '#')
1971 /* Start of a token */
1974 argv = xreallocarray(argv, (argc + 2), sizeof(*argv));
1975 arg = argv[argc++] = xcalloc(1, strlen(s + i) + 1);
1978 /* Copy the token in, removing escapes */
1979 for (j = 0; s[i] != '\0'; i++) {
1981 if (s[i + 1] == '\'' ||
1984 (quote == 0 && s[i + 1] == ' ')) {
1988 /* Unrecognised escape */
1991 } else if (quote == 0 && (s[i] == ' ' || s[i] == '\t'))
1993 else if (quote == 0 && (s[i] == '\"' || s[i] == '\''))
1994 quote = s[i]; /* quote start */
1995 else if (quote != 0 && s[i] == quote)
1996 quote = 0; /* quote end */
2002 /* Ran out of string looking for close quote */
2003 r = SSH_ERR_INVALID_FORMAT;
2016 if (argc != 0 && argv != NULL) {
2017 for (i = 0; i < argc; i++)
2025 * Reassemble an argument vector into a string, quoting and escaping as
2026 * necessary. Caller must free returned string.
2029 argv_assemble(int argc, char **argv)
2033 struct sshbuf *buf, *arg;
2035 if ((buf = sshbuf_new()) == NULL || (arg = sshbuf_new()) == NULL)
2036 fatal_f("sshbuf_new failed");
2038 for (i = 0; i < argc; i++) {
2041 for (j = 0; argv[i][j] != '\0'; j++) {
2048 r = sshbuf_put_u8(arg, c);
2053 if ((r = sshbuf_put_u8(arg, '\\')) != 0)
2057 r = sshbuf_put_u8(arg, c);
2061 fatal_fr(r, "sshbuf_put_u8");
2063 if ((i != 0 && (r = sshbuf_put_u8(buf, ' ')) != 0) ||
2064 (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0) ||
2065 (r = sshbuf_putb(buf, arg)) != 0 ||
2066 (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0))
2067 fatal_fr(r, "assemble");
2069 if ((ret = malloc(sshbuf_len(buf) + 1)) == NULL)
2070 fatal_f("malloc failed");
2071 memcpy(ret, sshbuf_ptr(buf), sshbuf_len(buf));
2072 ret[sshbuf_len(buf)] = '\0';
2079 argv_next(int *argcp, char ***argvp)
2081 char *ret = (*argvp)[0];
2083 if (*argcp > 0 && ret != NULL) {
2091 argv_consume(int *argcp)
2097 argv_free(char **av, int ac)
2103 for (i = 0; i < ac; i++)
2108 /* Returns 0 if pid exited cleanly, non-zero otherwise */
2110 exited_cleanly(pid_t pid, const char *tag, const char *cmd, int quiet)
2114 while (waitpid(pid, &status, 0) == -1) {
2115 if (errno != EINTR) {
2116 error("%s waitpid: %s", tag, strerror(errno));
2120 if (WIFSIGNALED(status)) {
2121 error("%s %s exited on signal %d", tag, cmd, WTERMSIG(status));
2123 } else if (WEXITSTATUS(status) != 0) {
2124 do_log2(quiet ? SYSLOG_LEVEL_DEBUG1 : SYSLOG_LEVEL_INFO,
2125 "%s %s failed, status %d", tag, cmd, WEXITSTATUS(status));
2132 * Check a given path for security. This is defined as all components
2133 * of the path to the file must be owned by either the owner of
2134 * of the file or root and no directories must be group or world writable.
2136 * XXX Should any specific check be done for sym links ?
2138 * Takes a file name, its stat information (preferably from fstat() to
2139 * avoid races), the uid of the expected owner, their home directory and an
2140 * error buffer plus max size as arguments.
2142 * Returns 0 on success and -1 on failure
2145 safe_path(const char *name, struct stat *stp, const char *pw_dir,
2146 uid_t uid, char *err, size_t errlen)
2148 char buf[PATH_MAX], homedir[PATH_MAX];
2150 int comparehome = 0;
2153 if (realpath(name, buf) == NULL) {
2154 snprintf(err, errlen, "realpath %s failed: %s", name,
2158 if (pw_dir != NULL && realpath(pw_dir, homedir) != NULL)
2161 if (!S_ISREG(stp->st_mode)) {
2162 snprintf(err, errlen, "%s is not a regular file", buf);
2165 if ((!platform_sys_dir_uid(stp->st_uid) && stp->st_uid != uid) ||
2166 (stp->st_mode & 022) != 0) {
2167 snprintf(err, errlen, "bad ownership or modes for file %s",
2172 /* for each component of the canonical path, walking upwards */
2174 if ((cp = dirname(buf)) == NULL) {
2175 snprintf(err, errlen, "dirname() failed");
2178 strlcpy(buf, cp, sizeof(buf));
2180 if (stat(buf, &st) == -1 ||
2181 (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) ||
2182 (st.st_mode & 022) != 0) {
2183 snprintf(err, errlen,
2184 "bad ownership or modes for directory %s", buf);
2188 /* If are past the homedir then we can stop */
2189 if (comparehome && strcmp(homedir, buf) == 0)
2193 * dirname should always complete with a "/" path,
2194 * but we can be paranoid and check for "." too
2196 if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0))
2203 * Version of safe_path() that accepts an open file descriptor to
2206 * Returns 0 on success and -1 on failure
2209 safe_path_fd(int fd, const char *file, struct passwd *pw,
2210 char *err, size_t errlen)
2214 /* check the open file to avoid races */
2215 if (fstat(fd, &st) == -1) {
2216 snprintf(err, errlen, "cannot stat file %s: %s",
2217 file, strerror(errno));
2220 return safe_path(file, &st, pw->pw_dir, pw->pw_uid, err, errlen);
2224 * Sets the value of the given variable in the environment. If the variable
2225 * already exists, its value is overridden.
2228 child_set_env(char ***envp, u_int *envsizep, const char *name,
2235 if (strchr(name, '=') != NULL) {
2236 error("Invalid environment variable \"%.100s\"", name);
2241 * If we're passed an uninitialized list, allocate a single null
2242 * entry before continuing.
2244 if (*envp == NULL && *envsizep == 0) {
2245 *envp = xmalloc(sizeof(char *));
2251 * Find the slot where the value should be stored. If the variable
2252 * already exists, we reuse the slot; otherwise we append a new slot
2253 * at the end of the array, expanding if necessary.
2256 namelen = strlen(name);
2257 for (i = 0; env[i]; i++)
2258 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
2261 /* Reuse the slot. */
2264 /* New variable. Expand if necessary. */
2265 envsize = *envsizep;
2266 if (i >= envsize - 1) {
2267 if (envsize >= 1000)
2268 fatal("child_set_env: too many env vars");
2270 env = (*envp) = xreallocarray(env, envsize, sizeof(char *));
2271 *envsizep = envsize;
2273 /* Need to set the NULL pointer at end of array beyond the new slot. */
2277 /* Allocate space and format the variable in the appropriate slot. */
2279 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
2280 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
2284 * Check and optionally lowercase a domain name, also removes trailing '.'
2285 * Returns 1 on success and 0 on failure, storing an error message in errstr.
2288 valid_domain(char *name, int makelower, const char **errstr)
2290 size_t i, l = strlen(name);
2291 u_char c, last = '\0';
2292 static char errbuf[256];
2295 strlcpy(errbuf, "empty domain name", sizeof(errbuf));
2298 if (!isalpha((u_char)name[0]) && !isdigit((u_char)name[0])) {
2299 snprintf(errbuf, sizeof(errbuf), "domain name \"%.100s\" "
2300 "starts with invalid character", name);
2303 for (i = 0; i < l; i++) {
2304 c = tolower((u_char)name[i]);
2307 if (last == '.' && c == '.') {
2308 snprintf(errbuf, sizeof(errbuf), "domain name "
2309 "\"%.100s\" contains consecutive separators", name);
2312 if (c != '.' && c != '-' && !isalnum(c) &&
2313 c != '_') /* technically invalid, but common */ {
2314 snprintf(errbuf, sizeof(errbuf), "domain name "
2315 "\"%.100s\" contains invalid characters", name);
2320 if (name[l - 1] == '.')
2332 * Verify that a environment variable name (not including initial '$') is
2333 * valid; consisting of one or more alphanumeric or underscore characters only.
2334 * Returns 1 on valid, 0 otherwise.
2337 valid_env_name(const char *name)
2341 if (name[0] == '\0')
2343 for (cp = name; *cp != '\0'; cp++) {
2344 if (!isalnum((u_char)*cp) && *cp != '_')
2351 atoi_err(const char *nptr, int *val)
2353 const char *errstr = NULL;
2356 if (nptr == NULL || *nptr == '\0')
2358 num = strtonum(nptr, 0, INT_MAX, &errstr);
2365 parse_absolute_time(const char *s, uint64_t *tp)
2374 * POSIX strptime says "The application shall ensure that there
2375 * is white-space or other non-alphanumeric characters between
2376 * any two conversion specifications" so arrange things this way.
2378 switch (strlen(s)) {
2379 case 8: /* YYYYMMDD */
2381 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2s", s, s + 4, s + 6);
2383 case 12: /* YYYYMMDDHHMM */
2384 fmt = "%Y-%m-%dT%H:%M";
2385 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s",
2386 s, s + 4, s + 6, s + 8, s + 10);
2388 case 14: /* YYYYMMDDHHMMSS */
2389 fmt = "%Y-%m-%dT%H:%M:%S";
2390 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s:%.2s",
2391 s, s + 4, s + 6, s + 8, s + 10, s + 12);
2394 return SSH_ERR_INVALID_FORMAT;
2397 memset(&tm, 0, sizeof(tm));
2398 if (strptime(buf, fmt, &tm) == NULL)
2399 return SSH_ERR_INVALID_FORMAT;
2400 if ((tt = mktime(&tm)) < 0)
2401 return SSH_ERR_INVALID_FORMAT;
2407 /* On OpenBSD time_t is int64_t which is long long. */
2408 /* #define SSH_TIME_T_MAX LLONG_MAX */
2411 format_absolute_time(uint64_t t, char *buf, size_t len)
2413 time_t tt = t > SSH_TIME_T_MAX ? SSH_TIME_T_MAX : t;
2416 localtime_r(&tt, &tm);
2417 strftime(buf, len, "%Y-%m-%dT%H:%M:%S", &tm);
2420 /* check if path is absolute */
2422 path_absolute(const char *path)
2424 return (*path == '/') ? 1 : 0;
2428 skip_space(char **cpp)
2432 for (cp = *cpp; *cp == ' ' || *cp == '\t'; cp++)
2437 /* authorized_key-style options parsing helpers */
2440 * Match flag 'opt' in *optsp, and if allow_negate is set then also match
2441 * 'no-opt'. Returns -1 if option not matched, 1 if option matches or 0
2442 * if negated option matches.
2443 * If the option or negated option matches, then *optsp is updated to
2444 * point to the first character after the option.
2447 opt_flag(const char *opt, int allow_negate, const char **optsp)
2449 size_t opt_len = strlen(opt);
2450 const char *opts = *optsp;
2453 if (allow_negate && strncasecmp(opts, "no-", 3) == 0) {
2457 if (strncasecmp(opts, opt, opt_len) == 0) {
2458 *optsp = opts + opt_len;
2459 return negate ? 0 : 1;
2465 opt_dequote(const char **sp, const char **errstrp)
2467 const char *s = *sp;
2473 *errstrp = "missing start quote";
2477 if ((ret = malloc(strlen((s)) + 1)) == NULL) {
2478 *errstrp = "memory allocation failed";
2481 for (i = 0; *s != '\0' && *s != '"';) {
2482 if (s[0] == '\\' && s[1] == '"')
2487 *errstrp = "missing end quote";
2498 opt_match(const char **opts, const char *term)
2500 if (strncasecmp((*opts), term, strlen(term)) == 0 &&
2501 (*opts)[strlen(term)] == '=') {
2502 *opts += strlen(term) + 1;
2509 opt_array_append2(const char *file, const int line, const char *directive,
2510 char ***array, int **iarray, u_int *lp, const char *s, int i)
2514 fatal("%s line %d: Too many %s entries", file, line, directive);
2516 if (iarray != NULL) {
2517 *iarray = xrecallocarray(*iarray, *lp, *lp + 1,
2522 *array = xrecallocarray(*array, *lp, *lp + 1, sizeof(**array));
2523 (*array)[*lp] = xstrdup(s);
2528 opt_array_append(const char *file, const int line, const char *directive,
2529 char ***array, u_int *lp, const char *s)
2531 opt_array_append2(file, line, directive, array, NULL, lp, s, 0);
2535 ssh_signal(int signum, sshsig_t handler)
2537 struct sigaction sa, osa;
2539 /* mask all other signals while in handler */
2540 memset(&sa, 0, sizeof(sa));
2541 sa.sa_handler = handler;
2542 sigfillset(&sa.sa_mask);
2543 #if defined(SA_RESTART) && !defined(NO_SA_RESTART)
2544 if (signum != SIGALRM)
2545 sa.sa_flags = SA_RESTART;
2547 if (sigaction(signum, &sa, &osa) == -1) {
2548 debug3("sigaction(%s): %s", strsignal(signum), strerror(errno));
2551 return osa.sa_handler;
2555 stdfd_devnull(int do_stdin, int do_stdout, int do_stderr)
2557 int devnull, ret = 0;
2559 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
2560 error_f("open %s: %s", _PATH_DEVNULL,
2564 if ((do_stdin && dup2(devnull, STDIN_FILENO) == -1) ||
2565 (do_stdout && dup2(devnull, STDOUT_FILENO) == -1) ||
2566 (do_stderr && dup2(devnull, STDERR_FILENO) == -1)) {
2567 error_f("dup2: %s", strerror(errno));
2570 if (devnull > STDERR_FILENO)
2576 * Runs command in a subprocess with a minimal environment.
2577 * Returns pid on success, 0 on failure.
2578 * The child stdout and stderr maybe captured, left attached or sent to
2579 * /dev/null depending on the contents of flags.
2580 * "tag" is prepended to log messages.
2581 * NB. "command" is only used for logging; the actual command executed is
2585 subprocess(const char *tag, const char *command,
2586 int ac, char **av, FILE **child, u_int flags,
2587 struct passwd *pw, privdrop_fn *drop_privs, privrestore_fn *restore_privs)
2591 int fd, devnull, p[2], i;
2593 char *cp, errmsg[512];
2597 /* If dropping privs, then must specify user and restore function */
2598 if (drop_privs != NULL && (pw == NULL || restore_privs == NULL)) {
2599 error("%s: inconsistent arguments", tag); /* XXX fatal? */
2602 if (pw == NULL && (pw = getpwuid(getuid())) == NULL) {
2603 error("%s: no user for current uid", tag);
2609 debug3_f("%s command \"%s\" running as %s (flags 0x%x)",
2610 tag, command, pw->pw_name, flags);
2612 /* Check consistency */
2613 if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
2614 (flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0) {
2615 error_f("inconsistent flags");
2618 if (((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0) != (child == NULL)) {
2619 error_f("inconsistent flags/output");
2624 * If executing an explicit binary, then verify the it exists
2625 * and appears safe-ish to execute
2627 if (!path_absolute(av[0])) {
2628 error("%s path is not absolute", tag);
2631 if (drop_privs != NULL)
2633 if (stat(av[0], &st) == -1) {
2634 error("Could not stat %s \"%s\": %s", tag,
2635 av[0], strerror(errno));
2636 goto restore_return;
2638 if ((flags & SSH_SUBPROCESS_UNSAFE_PATH) == 0 &&
2639 safe_path(av[0], &st, NULL, 0, errmsg, sizeof(errmsg)) != 0) {
2640 error("Unsafe %s \"%s\": %s", tag, av[0], errmsg);
2641 goto restore_return;
2643 /* Prepare to keep the child's stdout if requested */
2644 if (pipe(p) == -1) {
2645 error("%s: pipe: %s", tag, strerror(errno));
2647 if (restore_privs != NULL)
2651 if (restore_privs != NULL)
2654 switch ((pid = fork())) {
2655 case -1: /* error */
2656 error("%s: fork: %s", tag, strerror(errno));
2661 /* Prepare a minimal environment for the child. */
2662 if ((flags & SSH_SUBPROCESS_PRESERVE_ENV) == 0) {
2664 env = xcalloc(sizeof(*env), nenv);
2665 child_set_env(&env, &nenv, "PATH", _PATH_STDPATH);
2666 child_set_env(&env, &nenv, "USER", pw->pw_name);
2667 child_set_env(&env, &nenv, "LOGNAME", pw->pw_name);
2668 child_set_env(&env, &nenv, "HOME", pw->pw_dir);
2669 if ((cp = getenv("LANG")) != NULL)
2670 child_set_env(&env, &nenv, "LANG", cp);
2673 for (i = 1; i < NSIG; i++)
2674 ssh_signal(i, SIG_DFL);
2676 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
2677 error("%s: open %s: %s", tag, _PATH_DEVNULL,
2681 if (dup2(devnull, STDIN_FILENO) == -1) {
2682 error("%s: dup2: %s", tag, strerror(errno));
2686 /* Set up stdout as requested; leave stderr in place for now. */
2688 if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0)
2690 else if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0)
2692 if (fd != -1 && dup2(fd, STDOUT_FILENO) == -1) {
2693 error("%s: dup2: %s", tag, strerror(errno));
2696 closefrom(STDERR_FILENO + 1);
2698 if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) {
2699 error("%s: setresgid %u: %s", tag, (u_int)pw->pw_gid,
2703 if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1) {
2704 error("%s: setresuid %u: %s", tag, (u_int)pw->pw_uid,
2708 /* stdin is pointed to /dev/null at this point */
2709 if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
2710 dup2(STDIN_FILENO, STDERR_FILENO) == -1) {
2711 error("%s: dup2: %s", tag, strerror(errno));
2715 execve(av[0], av, env);
2718 error("%s %s \"%s\": %s", tag, env == NULL ? "execv" : "execve",
2719 command, strerror(errno));
2721 default: /* parent */
2726 if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0)
2728 else if ((f = fdopen(p[0], "r")) == NULL) {
2729 error("%s: fdopen: %s", tag, strerror(errno));
2731 /* Don't leave zombie child */
2733 while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
2738 debug3_f("%s pid %ld", tag, (long)pid);
2745 lookup_env_in_list(const char *env, char * const *envs, size_t nenvs)
2749 envlen = strlen(env);
2750 for (i = 0; i < nenvs; i++) {
2751 if (strncmp(envs[i], env, envlen) == 0 &&
2752 envs[i][envlen] == '=') {
2753 return envs[i] + envlen + 1;