1 /* $OpenBSD: misc.c,v 1.170 2021/09/26 14:01:03 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>
61 #ifdef SSH_TUN_OPENBSD
73 /* remove newline at end of string */
79 if (*t == '\n' || *t == '\r') {
89 /* remove whitespace from end of string */
95 if ((i = strlen(s)) == 0)
97 for (i--; i > 0; i--) {
98 if (isspace((int)s[i]))
103 /* set/unset filedescriptor to non-blocking */
109 val = fcntl(fd, F_GETFL);
111 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno));
114 if (val & O_NONBLOCK) {
115 debug3("fd %d is O_NONBLOCK", fd);
118 debug2("fd %d setting O_NONBLOCK", fd);
120 if (fcntl(fd, F_SETFL, val) == -1) {
121 debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd,
129 unset_nonblock(int fd)
133 val = fcntl(fd, F_GETFL);
135 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno));
138 if (!(val & O_NONBLOCK)) {
139 debug3("fd %d is not O_NONBLOCK", fd);
142 debug("fd %d clearing O_NONBLOCK", fd);
144 if (fcntl(fd, F_SETFL, val) == -1) {
145 debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s",
146 fd, strerror(errno));
153 ssh_gai_strerror(int gaierr)
155 if (gaierr == EAI_SYSTEM && errno != 0)
156 return strerror(errno);
157 return gai_strerror(gaierr);
160 /* disable nagle on socket */
168 if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) {
169 debug("getsockopt TCP_NODELAY: %.100s", strerror(errno));
173 debug2("fd %d is TCP_NODELAY", fd);
177 debug2("fd %d setting TCP_NODELAY", fd);
178 if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1)
179 error("setsockopt TCP_NODELAY: %.100s", strerror(errno));
182 /* Allow local port reuse in TIME_WAIT */
184 set_reuseaddr(int fd)
188 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) {
189 error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno));
195 /* Get/set routing domain */
199 #if defined(HAVE_SYS_GET_RDOMAIN)
200 return sys_get_rdomain(fd);
201 #elif defined(__OpenBSD__)
204 socklen_t len = sizeof(rtable);
206 if (getsockopt(fd, SOL_SOCKET, SO_RTABLE, &rtable, &len) == -1) {
207 error("Failed to get routing domain for fd %d: %s",
208 fd, strerror(errno));
211 xasprintf(&ret, "%d", rtable);
213 #else /* defined(__OpenBSD__) */
219 set_rdomain(int fd, const char *name)
221 #if defined(HAVE_SYS_SET_RDOMAIN)
222 return sys_set_rdomain(fd, name);
223 #elif defined(__OpenBSD__)
228 return 0; /* default table */
230 rtable = (int)strtonum(name, 0, 255, &errstr);
231 if (errstr != NULL) {
232 /* Shouldn't happen */
233 error("Invalid routing domain \"%s\": %s", name, errstr);
236 if (setsockopt(fd, SOL_SOCKET, SO_RTABLE,
237 &rtable, sizeof(rtable)) == -1) {
238 error("Failed to set routing domain %d on fd %d: %s",
239 rtable, fd, strerror(errno));
243 #else /* defined(__OpenBSD__) */
244 error("Setting routing domain is not supported on this platform");
252 struct sockaddr_storage to;
253 socklen_t tolen = sizeof(to);
255 memset(&to, 0, sizeof(to));
256 if (getsockname(fd, (struct sockaddr *)&to, &tolen) == -1)
259 if (to.ss_family == AF_INET6 &&
260 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr))
267 set_sock_tos(int fd, int tos)
269 #ifndef IP_TOS_IS_BROKEN
272 switch ((af = get_sock_af(fd))) {
274 /* assume not a socket */
278 debug3_f("set socket %d IP_TOS 0x%02x", fd, tos);
279 if (setsockopt(fd, IPPROTO_IP, IP_TOS,
280 &tos, sizeof(tos)) == -1) {
281 error("setsockopt socket %d IP_TOS %d: %s:",
282 fd, tos, strerror(errno));
288 debug3_f("set socket %d IPV6_TCLASS 0x%02x", fd, tos);
289 if (setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS,
290 &tos, sizeof(tos)) == -1) {
291 error("setsockopt socket %d IPV6_TCLASS %d: %.100s:",
292 fd, tos, strerror(errno));
294 # endif /* IPV6_TCLASS */
297 debug2_f("unsupported socket family %d", af);
300 #endif /* IP_TOS_IS_BROKEN */
304 * Wait up to *timeoutp milliseconds for events on fd. Updates
305 * *timeoutp with time remaining.
306 * Returns 0 if fd ready or -1 on timeout or error (see errno).
309 waitfd(int fd, int *timeoutp, short events)
312 struct timeval t_start;
317 for (; *timeoutp >= 0;) {
318 monotime_tv(&t_start);
319 r = poll(&pfd, 1, *timeoutp);
321 ms_subtract_diff(&t_start, timeoutp);
325 else if (r == -1 && errno != EAGAIN && errno != EINTR)
336 * Wait up to *timeoutp milliseconds for fd to be readable. Updates
337 * *timeoutp with time remaining.
338 * Returns 0 if fd ready or -1 on timeout or error (see errno).
341 waitrfd(int fd, int *timeoutp) {
342 return waitfd(fd, timeoutp, POLLIN);
346 * Attempt a non-blocking connect(2) to the specified address, waiting up to
347 * *timeoutp milliseconds for the connection to complete. If the timeout is
348 * <=0, then wait indefinitely.
350 * Returns 0 on success or -1 on failure.
353 timeout_connect(int sockfd, const struct sockaddr *serv_addr,
354 socklen_t addrlen, int *timeoutp)
357 socklen_t optlen = sizeof(optval);
359 /* No timeout: just do a blocking connect() */
360 if (timeoutp == NULL || *timeoutp <= 0)
361 return connect(sockfd, serv_addr, addrlen);
363 set_nonblock(sockfd);
365 if (connect(sockfd, serv_addr, addrlen) == 0) {
366 /* Succeeded already? */
367 unset_nonblock(sockfd);
369 } else if (errno == EINTR)
371 else if (errno != EINPROGRESS)
376 if (waitfd(sockfd, timeoutp, POLLIN | POLLOUT) == -1)
379 /* Completed or failed */
380 if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, &optlen) == -1) {
381 debug("getsockopt: %s", strerror(errno));
388 unset_nonblock(sockfd);
392 /* Characters considered whitespace in strsep calls. */
393 #define WHITESPACE " \t\r\n"
396 /* return next token in configuration line */
398 strdelim_internal(char **s, int split_equals)
409 split_equals ? WHITESPACE QUOTE "=" : WHITESPACE QUOTE);
414 memmove(*s, *s + 1, strlen(*s)); /* move nul too */
415 /* Find matching quote */
416 if ((*s = strpbrk(*s, QUOTE)) == NULL) {
417 return (NULL); /* no matching quote */
420 *s += strspn(*s + 1, WHITESPACE) + 1;
425 /* Allow only one '=' to be skipped */
426 if (split_equals && *s[0] == '=')
430 /* Skip any extra whitespace after first token */
431 *s += strspn(*s + 1, WHITESPACE) + 1;
432 if (split_equals && *s[0] == '=' && !wspace)
433 *s += strspn(*s + 1, WHITESPACE) + 1;
439 * Return next token in configuration line; splts on whitespace or a
440 * single '=' character.
445 return strdelim_internal(s, 1);
449 * Return next token in configuration line; splts on whitespace only.
454 return strdelim_internal(s, 0);
458 pwcopy(struct passwd *pw)
460 struct passwd *copy = xcalloc(1, sizeof(*copy));
462 copy->pw_name = xstrdup(pw->pw_name);
463 copy->pw_passwd = xstrdup(pw->pw_passwd == NULL ? "*" : pw->pw_passwd);
464 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS
465 copy->pw_gecos = xstrdup(pw->pw_gecos);
467 copy->pw_uid = pw->pw_uid;
468 copy->pw_gid = pw->pw_gid;
469 #ifdef HAVE_STRUCT_PASSWD_PW_EXPIRE
470 copy->pw_expire = pw->pw_expire;
472 #ifdef HAVE_STRUCT_PASSWD_PW_CHANGE
473 copy->pw_change = pw->pw_change;
475 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS
476 copy->pw_class = xstrdup(pw->pw_class);
478 copy->pw_dir = xstrdup(pw->pw_dir);
479 copy->pw_shell = xstrdup(pw->pw_shell);
484 * Convert ASCII string to TCP/IP port number.
485 * Port must be >=0 and <=65535.
486 * Return -1 if invalid.
489 a2port(const char *s)
495 port = strtonum(s, 0, 65535, &errstr);
498 if ((se = getservbyname(s, "tcp")) != NULL)
499 return ntohs(se->s_port);
504 a2tun(const char *s, int *remote)
506 const char *errstr = NULL;
510 if (remote != NULL) {
511 *remote = SSH_TUNID_ANY;
513 if ((ep = strchr(sp, ':')) == NULL) {
515 return (a2tun(s, NULL));
518 *remote = a2tun(ep, NULL);
519 tun = a2tun(sp, NULL);
521 return (*remote == SSH_TUNID_ERR ? *remote : tun);
524 if (strcasecmp(s, "any") == 0)
525 return (SSH_TUNID_ANY);
527 tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr);
529 return (SSH_TUNID_ERR);
535 #define MINUTES (SECONDS * 60)
536 #define HOURS (MINUTES * 60)
537 #define DAYS (HOURS * 24)
538 #define WEEKS (DAYS * 7)
541 * Convert a time string into seconds; format is
545 * Valid time qualifiers are:
559 * Return -1 if time string is invalid.
562 convtime(const char *s)
564 long total, secs, multiplier;
572 if (p == NULL || *p == '\0')
576 secs = strtol(p, &endp, 10);
578 (errno == ERANGE && (secs == INT_MIN || secs == INT_MAX)) ||
592 multiplier = MINUTES;
609 if (secs > INT_MAX / multiplier)
612 if (total > INT_MAX - secs)
627 fmt_timeframe(time_t t)
630 static char tfbuf[TF_BUFS][TF_LEN]; /* ring buffer */
632 unsigned int sec, min, hrs, day;
633 unsigned long long week;
651 snprintf(buf, TF_LEN, "%02lluw%01ud%02uh", week, day, hrs);
653 snprintf(buf, TF_LEN, "%01ud%02uh%02um", day, hrs, min);
655 snprintf(buf, TF_LEN, "%02u:%02u:%02u", hrs, min, sec);
661 * Returns a standardized host+port identifier string.
662 * Caller must free returned string.
665 put_host_port(const char *host, u_short port)
669 if (port == 0 || port == SSH_DEFAULT_PORT)
670 return(xstrdup(host));
671 if (asprintf(&hoststr, "[%s]:%d", host, (int)port) == -1)
672 fatal("put_host_port: asprintf: %s", strerror(errno));
673 debug3("put_host_port: %s", hoststr);
678 * Search for next delimiter between hostnames/addresses and ports.
679 * Argument may be modified (for termination).
680 * Returns *cp if parsing succeeds.
681 * *cp is set to the start of the next field, if one was found.
682 * The delimiter char, if present, is stored in delim.
683 * If this is the last field, *cp is set to NULL.
686 hpdelim2(char **cp, char *delim)
690 if (cp == NULL || *cp == NULL)
695 if ((s = strchr(s, ']')) == NULL)
699 } else if ((s = strpbrk(s, ":/")) == NULL)
700 s = *cp + strlen(*cp); /* skip to end (see first case below) */
704 *cp = NULL; /* no more fields*/
711 *s = '\0'; /* terminate */
725 return hpdelim2(cp, NULL);
729 cleanhostname(char *host)
731 if (*host == '[' && host[strlen(host) - 1] == ']') {
732 host[strlen(host) - 1] = '\0';
743 if (*cp == ':') /* Leading colon is part of file name. */
749 if (*cp == '@' && *(cp+1) == '[')
751 if (*cp == ']' && *(cp+1) == ':' && flag)
753 if (*cp == ':' && !flag)
762 * Parse a [user@]host:[path] string.
763 * Caller must free returned user, host and path.
764 * Any of the pointer return arguments may be NULL (useful for syntax checking).
765 * If user was not specified then *userp will be set to NULL.
766 * If host was not specified then *hostp will be set to NULL.
767 * If path was not specified then *pathp will be set to ".".
768 * Returns 0 on success, -1 on failure.
771 parse_user_host_path(const char *s, char **userp, char **hostp, char **pathp)
773 char *user = NULL, *host = NULL, *path = NULL;
786 /* Check for remote syntax: [user@]host:[path] */
787 if ((tmp = colon(sdup)) == NULL)
790 /* Extract optional path */
796 /* Extract optional user and mandatory host */
797 tmp = strrchr(sdup, '@');
800 host = xstrdup(cleanhostname(tmp));
802 user = xstrdup(sdup);
804 host = xstrdup(cleanhostname(sdup));
831 * Parse a [user@]host[:port] string.
832 * Caller must free returned user and host.
833 * Any of the pointer return arguments may be NULL (useful for syntax checking).
834 * If user was not specified then *userp will be set to NULL.
835 * If port was not specified then *portp will be -1.
836 * Returns 0 on success, -1 on failure.
839 parse_user_host_port(const char *s, char **userp, char **hostp, int *portp)
841 char *sdup, *cp, *tmp;
842 char *user = NULL, *host = NULL;
843 int port = -1, ret = -1;
852 if ((sdup = tmp = strdup(s)) == NULL)
854 /* Extract optional username */
855 if ((cp = strrchr(tmp, '@')) != NULL) {
859 if ((user = strdup(tmp)) == NULL)
863 /* Extract mandatory hostname */
864 if ((cp = hpdelim(&tmp)) == NULL || *cp == '\0')
866 host = xstrdup(cleanhostname(cp));
867 /* Convert and verify optional port */
868 if (tmp != NULL && *tmp != '\0') {
869 if ((port = a2port(tmp)) <= 0)
892 * Converts a two-byte hex string to decimal.
893 * Returns the decimal value or -1 for invalid input.
896 hexchar(const char *s)
898 unsigned char result[2];
901 for (i = 0; i < 2; i++) {
902 if (s[i] >= '0' && s[i] <= '9')
903 result[i] = (unsigned char)(s[i] - '0');
904 else if (s[i] >= 'a' && s[i] <= 'f')
905 result[i] = (unsigned char)(s[i] - 'a') + 10;
906 else if (s[i] >= 'A' && s[i] <= 'F')
907 result[i] = (unsigned char)(s[i] - 'A') + 10;
911 return (result[0] << 4) | result[1];
915 * Decode an url-encoded string.
916 * Returns a newly allocated string on success or NULL on failure.
919 urldecode(const char *src)
924 ret = xmalloc(strlen(src) + 1);
925 for (dst = ret; *src != '\0'; src++) {
931 if (!isxdigit((unsigned char)src[1]) ||
932 !isxdigit((unsigned char)src[2]) ||
933 (ch = hexchar(src + 1)) == -1) {
951 * Parse an (scp|ssh|sftp)://[user@]host[:port][/path] URI.
952 * See https://tools.ietf.org/html/draft-ietf-secsh-scp-sftp-ssh-uri-04
953 * Either user or path may be url-encoded (but not host or port).
954 * Caller must free returned user, host and path.
955 * Any of the pointer return arguments may be NULL (useful for syntax checking)
956 * but the scheme must always be specified.
957 * If user was not specified then *userp will be set to NULL.
958 * If port was not specified then *portp will be -1.
959 * If path was not specified then *pathp will be set to NULL.
960 * Returns 0 on success, 1 if non-uri/wrong scheme, -1 on error/invalid uri.
963 parse_uri(const char *scheme, const char *uri, char **userp, char **hostp,
964 int *portp, char **pathp)
966 char *uridup, *cp, *tmp, ch;
967 char *user = NULL, *host = NULL, *path = NULL;
968 int port = -1, ret = -1;
971 len = strlen(scheme);
972 if (strncmp(uri, scheme, len) != 0 || strncmp(uri + len, "://", 3) != 0)
985 uridup = tmp = xstrdup(uri);
987 /* Extract optional ssh-info (username + connection params) */
988 if ((cp = strchr(tmp, '@')) != NULL) {
992 /* Extract username and connection params */
993 if ((delim = strchr(tmp, ';')) != NULL) {
994 /* Just ignore connection params for now */
1001 if ((user = urldecode(tmp)) == NULL)
1006 /* Extract mandatory hostname */
1007 if ((cp = hpdelim2(&tmp, &ch)) == NULL || *cp == '\0')
1009 host = xstrdup(cleanhostname(cp));
1010 if (!valid_domain(host, 0, NULL))
1013 if (tmp != NULL && *tmp != '\0') {
1015 /* Convert and verify port. */
1016 if ((cp = strchr(tmp, '/')) != NULL)
1018 if ((port = a2port(tmp)) <= 0)
1020 tmp = cp ? cp + 1 : NULL;
1022 if (tmp != NULL && *tmp != '\0') {
1023 /* Extract optional path */
1024 if ((path = urldecode(tmp)) == NULL)
1030 if (userp != NULL) {
1034 if (hostp != NULL) {
1040 if (pathp != NULL) {
1053 /* function to assist building execv() arguments */
1055 addargs(arglist *args, char *fmt, ...)
1063 r = vasprintf(&cp, fmt, ap);
1066 fatal("addargs: argument too long");
1068 nalloc = args->nalloc;
1069 if (args->list == NULL) {
1072 } else if (args->num+2 >= nalloc)
1075 args->list = xrecallocarray(args->list, args->nalloc, nalloc, sizeof(char *));
1076 args->nalloc = nalloc;
1077 args->list[args->num++] = cp;
1078 args->list[args->num] = NULL;
1082 replacearg(arglist *args, u_int which, char *fmt, ...)
1089 r = vasprintf(&cp, fmt, ap);
1092 fatal("replacearg: argument too long");
1094 if (which >= args->num)
1095 fatal("replacearg: tried to replace invalid arg %d >= %d",
1097 free(args->list[which]);
1098 args->list[which] = cp;
1102 freeargs(arglist *args)
1106 if (args->list != NULL) {
1107 for (i = 0; i < args->num; i++)
1108 free(args->list[i]);
1110 args->nalloc = args->num = 0;
1116 * Expands tildes in the file name. Returns data allocated by xmalloc.
1117 * Warning: this calls getpw*.
1120 tilde_expand(const char *filename, uid_t uid, char **retp)
1122 const char *path, *sep;
1123 char user[128], *ret;
1127 if (*filename != '~') {
1128 *retp = xstrdup(filename);
1133 path = strchr(filename, '/');
1134 if (path != NULL && path > filename) { /* ~user/path */
1135 slash = path - filename;
1136 if (slash > sizeof(user) - 1) {
1137 error_f("~username too long");
1140 memcpy(user, filename, slash);
1142 if ((pw = getpwnam(user)) == NULL) {
1143 error_f("No such user %s", user);
1146 } else if ((pw = getpwuid(uid)) == NULL) { /* ~/path */
1147 error_f("No such uid %ld", (long)uid);
1151 /* Make sure directory has a trailing '/' */
1152 len = strlen(pw->pw_dir);
1153 if (len == 0 || pw->pw_dir[len - 1] != '/')
1158 /* Skip leading '/' from specified path */
1160 filename = path + 1;
1162 if (xasprintf(&ret, "%s%s%s", pw->pw_dir, sep, filename) >= PATH_MAX) {
1163 error_f("Path too long");
1172 tilde_expand_filename(const char *filename, uid_t uid)
1176 if (tilde_expand(filename, uid, &ret) != 0)
1182 * Expand a string with a set of %[char] escapes and/or ${ENVIRONMENT}
1183 * substitutions. A number of escapes may be specified as
1184 * (char *escape_chars, char *replacement) pairs. The list must be terminated
1185 * by a NULL escape_char. Returns replaced string in memory allocated by
1186 * xmalloc which the caller must free.
1189 vdollar_percent_expand(int *parseerror, int dollar, int percent,
1190 const char *string, va_list ap)
1192 #define EXPAND_MAX_KEYS 16
1193 u_int num_keys = 0, i;
1197 } keys[EXPAND_MAX_KEYS];
1199 int r, missingvar = 0;
1200 char *ret = NULL, *var, *varend, *val;
1203 if ((buf = sshbuf_new()) == NULL)
1204 fatal_f("sshbuf_new failed");
1205 if (parseerror == NULL)
1206 fatal_f("null parseerror arg");
1209 /* Gather keys if we're doing percent expansion. */
1211 for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) {
1212 keys[num_keys].key = va_arg(ap, char *);
1213 if (keys[num_keys].key == NULL)
1215 keys[num_keys].repl = va_arg(ap, char *);
1216 if (keys[num_keys].repl == NULL) {
1217 fatal_f("NULL replacement for token %s",
1218 keys[num_keys].key);
1221 if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL)
1222 fatal_f("too many keys");
1224 fatal_f("percent expansion without token list");
1228 for (i = 0; *string != '\0'; string++) {
1229 /* Optionally process ${ENVIRONMENT} expansions. */
1230 if (dollar && string[0] == '$' && string[1] == '{') {
1231 string += 2; /* skip over '${' */
1232 if ((varend = strchr(string, '}')) == NULL) {
1233 error_f("environment variable '%s' missing "
1234 "closing '}'", string);
1237 len = varend - string;
1239 error_f("zero-length environment variable");
1242 var = xmalloc(len + 1);
1243 (void)strlcpy(var, string, len + 1);
1244 if ((val = getenv(var)) == NULL) {
1245 error_f("env var ${%s} has no value", var);
1248 debug3_f("expand ${%s} -> '%s'", var, val);
1249 if ((r = sshbuf_put(buf, val, strlen(val))) !=0)
1250 fatal_fr(r, "sshbuf_put ${}");
1258 * Process percent expansions if we have a list of TOKENs.
1259 * If we're not doing percent expansion everything just gets
1262 if (*string != '%' || !percent) {
1264 if ((r = sshbuf_put_u8(buf, *string)) != 0)
1265 fatal_fr(r, "sshbuf_put_u8 %%");
1272 if (*string == '\0') {
1273 error_f("invalid format");
1276 for (i = 0; i < num_keys; i++) {
1277 if (strchr(keys[i].key, *string) != NULL) {
1278 if ((r = sshbuf_put(buf, keys[i].repl,
1279 strlen(keys[i].repl))) != 0)
1280 fatal_fr(r, "sshbuf_put %%-repl");
1284 if (i >= num_keys) {
1285 error_f("unknown key %%%c", *string);
1289 if (!missingvar && (ret = sshbuf_dup_string(buf)) == NULL)
1290 fatal_f("sshbuf_dup_string failed");
1294 return *parseerror ? NULL : ret;
1295 #undef EXPAND_MAX_KEYS
1299 * Expand only environment variables.
1300 * Note that although this function is variadic like the other similar
1301 * functions, any such arguments will be unused.
1305 dollar_expand(int *parseerr, const char *string, ...)
1311 va_start(ap, string);
1312 ret = vdollar_percent_expand(&err, 1, 0, string, ap);
1314 if (parseerr != NULL)
1320 * Returns expanded string or NULL if a specified environment variable is
1321 * not defined, or calls fatal if the string is invalid.
1324 percent_expand(const char *string, ...)
1330 va_start(ap, string);
1331 ret = vdollar_percent_expand(&err, 0, 1, string, ap);
1339 * Returns expanded string or NULL if a specified environment variable is
1340 * not defined, or calls fatal if the string is invalid.
1343 percent_dollar_expand(const char *string, ...)
1349 va_start(ap, string);
1350 ret = vdollar_percent_expand(&err, 1, 1, string, ap);
1358 tun_open(int tun, int mode, char **ifname)
1360 #if defined(CUSTOM_SYS_TUN_OPEN)
1361 return (sys_tun_open(tun, mode, ifname));
1362 #elif defined(SSH_TUN_OPENBSD)
1366 const char *tunbase = "tun";
1371 if (mode == SSH_TUNMODE_ETHERNET)
1374 /* Open the tunnel device */
1375 if (tun <= SSH_TUNID_MAX) {
1376 snprintf(name, sizeof(name), "/dev/%s%d", tunbase, tun);
1377 fd = open(name, O_RDWR);
1378 } else if (tun == SSH_TUNID_ANY) {
1379 for (tun = 100; tun >= 0; tun--) {
1380 snprintf(name, sizeof(name), "/dev/%s%d",
1382 if ((fd = open(name, O_RDWR)) >= 0)
1386 debug_f("invalid tunnel %u", tun);
1391 debug_f("%s open: %s", name, strerror(errno));
1395 debug_f("%s mode %d fd %d", name, mode, fd);
1397 /* Bring interface up if it is not already */
1398 snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d", tunbase, tun);
1399 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
1402 if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) {
1403 debug_f("get interface %s flags: %s", ifr.ifr_name,
1408 if (!(ifr.ifr_flags & IFF_UP)) {
1409 ifr.ifr_flags |= IFF_UP;
1410 if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) {
1411 debug_f("activate interface %s: %s", ifr.ifr_name,
1418 *ifname = xstrdup(ifr.ifr_name);
1430 error("Tunnel interfaces are not supported on this platform");
1436 sanitise_stdfd(void)
1440 if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1441 fprintf(stderr, "Couldn't open /dev/null: %s\n",
1445 while (++dupfd <= STDERR_FILENO) {
1446 /* Only populate closed fds. */
1447 if (fcntl(dupfd, F_GETFL) == -1 && errno == EBADF) {
1448 if (dup2(nullfd, dupfd) == -1) {
1449 fprintf(stderr, "dup2: %s\n", strerror(errno));
1454 if (nullfd > STDERR_FILENO)
1459 tohex(const void *vp, size_t l)
1461 const u_char *p = (const u_char *)vp;
1466 return xstrdup("tohex: length > 65536");
1470 for (i = 0; i < l; i++) {
1471 snprintf(b, sizeof(b), "%02x", p[i]);
1478 * Extend string *sp by the specified format. If *sp is not NULL (or empty),
1479 * then the separator 'sep' will be prepended before the formatted arguments.
1480 * Extended strings are heap allocated.
1483 xextendf(char **sp, const char *sep, const char *fmt, ...)
1489 xvasprintf(&tmp1, fmt, ap);
1492 if (*sp == NULL || **sp == '\0') {
1497 xasprintf(&tmp2, "%s%s%s", *sp, sep == NULL ? "" : sep, tmp1);
1505 get_u64(const void *vp)
1507 const u_char *p = (const u_char *)vp;
1510 v = (u_int64_t)p[0] << 56;
1511 v |= (u_int64_t)p[1] << 48;
1512 v |= (u_int64_t)p[2] << 40;
1513 v |= (u_int64_t)p[3] << 32;
1514 v |= (u_int64_t)p[4] << 24;
1515 v |= (u_int64_t)p[5] << 16;
1516 v |= (u_int64_t)p[6] << 8;
1517 v |= (u_int64_t)p[7];
1523 get_u32(const void *vp)
1525 const u_char *p = (const u_char *)vp;
1528 v = (u_int32_t)p[0] << 24;
1529 v |= (u_int32_t)p[1] << 16;
1530 v |= (u_int32_t)p[2] << 8;
1531 v |= (u_int32_t)p[3];
1537 get_u32_le(const void *vp)
1539 const u_char *p = (const u_char *)vp;
1542 v = (u_int32_t)p[0];
1543 v |= (u_int32_t)p[1] << 8;
1544 v |= (u_int32_t)p[2] << 16;
1545 v |= (u_int32_t)p[3] << 24;
1551 get_u16(const void *vp)
1553 const u_char *p = (const u_char *)vp;
1556 v = (u_int16_t)p[0] << 8;
1557 v |= (u_int16_t)p[1];
1563 put_u64(void *vp, u_int64_t v)
1565 u_char *p = (u_char *)vp;
1567 p[0] = (u_char)(v >> 56) & 0xff;
1568 p[1] = (u_char)(v >> 48) & 0xff;
1569 p[2] = (u_char)(v >> 40) & 0xff;
1570 p[3] = (u_char)(v >> 32) & 0xff;
1571 p[4] = (u_char)(v >> 24) & 0xff;
1572 p[5] = (u_char)(v >> 16) & 0xff;
1573 p[6] = (u_char)(v >> 8) & 0xff;
1574 p[7] = (u_char)v & 0xff;
1578 put_u32(void *vp, u_int32_t v)
1580 u_char *p = (u_char *)vp;
1582 p[0] = (u_char)(v >> 24) & 0xff;
1583 p[1] = (u_char)(v >> 16) & 0xff;
1584 p[2] = (u_char)(v >> 8) & 0xff;
1585 p[3] = (u_char)v & 0xff;
1589 put_u32_le(void *vp, u_int32_t v)
1591 u_char *p = (u_char *)vp;
1593 p[0] = (u_char)v & 0xff;
1594 p[1] = (u_char)(v >> 8) & 0xff;
1595 p[2] = (u_char)(v >> 16) & 0xff;
1596 p[3] = (u_char)(v >> 24) & 0xff;
1600 put_u16(void *vp, u_int16_t v)
1602 u_char *p = (u_char *)vp;
1604 p[0] = (u_char)(v >> 8) & 0xff;
1605 p[1] = (u_char)v & 0xff;
1609 ms_subtract_diff(struct timeval *start, int *ms)
1611 struct timeval diff, finish;
1613 monotime_tv(&finish);
1614 timersub(&finish, start, &diff);
1615 *ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000);
1619 ms_to_timeval(struct timeval *tv, int ms)
1623 tv->tv_sec = ms / 1000;
1624 tv->tv_usec = (ms % 1000) * 1000;
1628 monotime_ts(struct timespec *ts)
1631 #if defined(HAVE_CLOCK_GETTIME) && (defined(CLOCK_BOOTTIME) || \
1632 defined(CLOCK_MONOTONIC) || defined(CLOCK_REALTIME))
1633 static int gettime_failed = 0;
1635 if (!gettime_failed) {
1636 # ifdef CLOCK_BOOTTIME
1637 if (clock_gettime(CLOCK_BOOTTIME, ts) == 0)
1639 # endif /* CLOCK_BOOTTIME */
1640 # ifdef CLOCK_MONOTONIC
1641 if (clock_gettime(CLOCK_MONOTONIC, ts) == 0)
1643 # endif /* CLOCK_MONOTONIC */
1644 # ifdef CLOCK_REALTIME
1645 /* Not monotonic, but we're almost out of options here. */
1646 if (clock_gettime(CLOCK_REALTIME, ts) == 0)
1648 # endif /* CLOCK_REALTIME */
1649 debug3("clock_gettime: %s", strerror(errno));
1652 #endif /* HAVE_CLOCK_GETTIME && (BOOTTIME || MONOTONIC || REALTIME) */
1653 gettimeofday(&tv, NULL);
1654 ts->tv_sec = tv.tv_sec;
1655 ts->tv_nsec = (long)tv.tv_usec * 1000;
1659 monotime_tv(struct timeval *tv)
1664 tv->tv_sec = ts.tv_sec;
1665 tv->tv_usec = ts.tv_nsec / 1000;
1678 monotime_double(void)
1683 return ts.tv_sec + ((double)ts.tv_nsec / 1000000000);
1687 bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen)
1689 bw->buflen = buflen;
1691 bw->thresh = buflen;
1693 timerclear(&bw->bwstart);
1694 timerclear(&bw->bwend);
1697 /* Callback from read/write loop to insert bandwidth-limiting delays */
1699 bandwidth_limit(struct bwlimit *bw, size_t read_len)
1702 struct timespec ts, rm;
1704 bw->lamt += read_len;
1705 if (!timerisset(&bw->bwstart)) {
1706 monotime_tv(&bw->bwstart);
1709 if (bw->lamt < bw->thresh)
1712 monotime_tv(&bw->bwend);
1713 timersub(&bw->bwend, &bw->bwstart, &bw->bwend);
1714 if (!timerisset(&bw->bwend))
1718 waitlen = (double)1000000L * bw->lamt / bw->rate;
1720 bw->bwstart.tv_sec = waitlen / 1000000L;
1721 bw->bwstart.tv_usec = waitlen % 1000000L;
1723 if (timercmp(&bw->bwstart, &bw->bwend, >)) {
1724 timersub(&bw->bwstart, &bw->bwend, &bw->bwend);
1726 /* Adjust the wait time */
1727 if (bw->bwend.tv_sec) {
1729 if (bw->thresh < bw->buflen / 4)
1730 bw->thresh = bw->buflen / 4;
1731 } else if (bw->bwend.tv_usec < 10000) {
1733 if (bw->thresh > bw->buflen * 8)
1734 bw->thresh = bw->buflen * 8;
1737 TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts);
1738 while (nanosleep(&ts, &rm) == -1) {
1746 monotime_tv(&bw->bwstart);
1749 /* Make a template filename for mk[sd]temp() */
1751 mktemp_proto(char *s, size_t len)
1756 if ((tmpdir = getenv("TMPDIR")) != NULL) {
1757 r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir);
1758 if (r > 0 && (size_t)r < len)
1761 r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX");
1762 if (r < 0 || (size_t)r >= len)
1763 fatal_f("template string too short");
1766 static const struct {
1770 { "none", INT_MAX }, /* can't use 0 here; that's CS0 */
1771 { "af11", IPTOS_DSCP_AF11 },
1772 { "af12", IPTOS_DSCP_AF12 },
1773 { "af13", IPTOS_DSCP_AF13 },
1774 { "af21", IPTOS_DSCP_AF21 },
1775 { "af22", IPTOS_DSCP_AF22 },
1776 { "af23", IPTOS_DSCP_AF23 },
1777 { "af31", IPTOS_DSCP_AF31 },
1778 { "af32", IPTOS_DSCP_AF32 },
1779 { "af33", IPTOS_DSCP_AF33 },
1780 { "af41", IPTOS_DSCP_AF41 },
1781 { "af42", IPTOS_DSCP_AF42 },
1782 { "af43", IPTOS_DSCP_AF43 },
1783 { "cs0", IPTOS_DSCP_CS0 },
1784 { "cs1", IPTOS_DSCP_CS1 },
1785 { "cs2", IPTOS_DSCP_CS2 },
1786 { "cs3", IPTOS_DSCP_CS3 },
1787 { "cs4", IPTOS_DSCP_CS4 },
1788 { "cs5", IPTOS_DSCP_CS5 },
1789 { "cs6", IPTOS_DSCP_CS6 },
1790 { "cs7", IPTOS_DSCP_CS7 },
1791 { "ef", IPTOS_DSCP_EF },
1792 { "le", IPTOS_DSCP_LE },
1793 { "lowdelay", IPTOS_LOWDELAY },
1794 { "throughput", IPTOS_THROUGHPUT },
1795 { "reliability", IPTOS_RELIABILITY },
1800 parse_ipqos(const char *cp)
1808 for (i = 0; ipqos[i].name != NULL; i++) {
1809 if (strcasecmp(cp, ipqos[i].name) == 0)
1810 return ipqos[i].value;
1812 /* Try parsing as an integer */
1813 val = strtol(cp, &ep, 0);
1814 if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255)
1820 iptos2str(int iptos)
1823 static char iptos_str[sizeof "0xff"];
1825 for (i = 0; ipqos[i].name != NULL; i++) {
1826 if (ipqos[i].value == iptos)
1827 return ipqos[i].name;
1829 snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos);
1837 *s = tolower((u_char)*s);
1841 unix_listener(const char *path, int backlog, int unlink_first)
1843 struct sockaddr_un sunaddr;
1844 int saved_errno, sock;
1846 memset(&sunaddr, 0, sizeof(sunaddr));
1847 sunaddr.sun_family = AF_UNIX;
1848 if (strlcpy(sunaddr.sun_path, path,
1849 sizeof(sunaddr.sun_path)) >= sizeof(sunaddr.sun_path)) {
1850 error_f("path \"%s\" too long for Unix domain socket", path);
1851 errno = ENAMETOOLONG;
1855 sock = socket(PF_UNIX, SOCK_STREAM, 0);
1857 saved_errno = errno;
1858 error_f("socket: %.100s", strerror(errno));
1859 errno = saved_errno;
1862 if (unlink_first == 1) {
1863 if (unlink(path) != 0 && errno != ENOENT)
1864 error("unlink(%s): %.100s", path, strerror(errno));
1866 if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) == -1) {
1867 saved_errno = errno;
1868 error_f("cannot bind to path %s: %s", path, strerror(errno));
1870 errno = saved_errno;
1873 if (listen(sock, backlog) == -1) {
1874 saved_errno = errno;
1875 error_f("cannot listen on path %s: %s", path, strerror(errno));
1878 errno = saved_errno;
1885 sock_set_v6only(int s)
1887 #if defined(IPV6_V6ONLY) && !defined(__OpenBSD__)
1890 debug3("%s: set socket %d IPV6_V6ONLY", __func__, s);
1891 if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1)
1892 error("setsockopt IPV6_V6ONLY: %s", strerror(errno));
1897 * Compares two strings that maybe be NULL. Returns non-zero if strings
1898 * are both NULL or are identical, returns zero otherwise.
1901 strcmp_maybe_null(const char *a, const char *b)
1903 if ((a == NULL && b != NULL) || (a != NULL && b == NULL))
1905 if (a != NULL && strcmp(a, b) != 0)
1911 * Compare two forwards, returning non-zero if they are identical or
1915 forward_equals(const struct Forward *a, const struct Forward *b)
1917 if (strcmp_maybe_null(a->listen_host, b->listen_host) == 0)
1919 if (a->listen_port != b->listen_port)
1921 if (strcmp_maybe_null(a->listen_path, b->listen_path) == 0)
1923 if (strcmp_maybe_null(a->connect_host, b->connect_host) == 0)
1925 if (a->connect_port != b->connect_port)
1927 if (strcmp_maybe_null(a->connect_path, b->connect_path) == 0)
1929 /* allocated_port and handle are not checked */
1933 /* returns 1 if process is already daemonized, 0 otherwise */
1939 if ((fd = open(_PATH_TTY, O_RDONLY | O_NOCTTY)) >= 0) {
1941 return 0; /* have controlling terminal */
1944 return 0; /* parent is not init */
1945 if (getsid(0) != getpid())
1946 return 0; /* not session leader */
1947 debug3("already daemonized");
1952 * Splits 's' into an argument vector. Handles quoted string and basic
1953 * escape characters (\\, \", \'). Caller must free the argument vector
1957 argv_split(const char *s, int *argcp, char ***argvp, int terminate_on_comment)
1959 int r = SSH_ERR_INTERNAL_ERROR;
1960 int argc = 0, quote, i, j;
1961 char *arg, **argv = xcalloc(1, sizeof(*argv));
1966 for (i = 0; s[i] != '\0'; i++) {
1967 /* Skip leading whitespace */
1968 if (s[i] == ' ' || s[i] == '\t')
1970 if (terminate_on_comment && s[i] == '#')
1972 /* Start of a token */
1975 argv = xreallocarray(argv, (argc + 2), sizeof(*argv));
1976 arg = argv[argc++] = xcalloc(1, strlen(s + i) + 1);
1979 /* Copy the token in, removing escapes */
1980 for (j = 0; s[i] != '\0'; i++) {
1982 if (s[i + 1] == '\'' ||
1985 (quote == 0 && s[i + 1] == ' ')) {
1989 /* Unrecognised escape */
1992 } else if (quote == 0 && (s[i] == ' ' || s[i] == '\t'))
1994 else if (quote == 0 && (s[i] == '\"' || s[i] == '\''))
1995 quote = s[i]; /* quote start */
1996 else if (quote != 0 && s[i] == quote)
1997 quote = 0; /* quote end */
2003 /* Ran out of string looking for close quote */
2004 r = SSH_ERR_INVALID_FORMAT;
2017 if (argc != 0 && argv != NULL) {
2018 for (i = 0; i < argc; i++)
2026 * Reassemble an argument vector into a string, quoting and escaping as
2027 * necessary. Caller must free returned string.
2030 argv_assemble(int argc, char **argv)
2034 struct sshbuf *buf, *arg;
2036 if ((buf = sshbuf_new()) == NULL || (arg = sshbuf_new()) == NULL)
2037 fatal_f("sshbuf_new failed");
2039 for (i = 0; i < argc; i++) {
2042 for (j = 0; argv[i][j] != '\0'; j++) {
2049 r = sshbuf_put_u8(arg, c);
2054 if ((r = sshbuf_put_u8(arg, '\\')) != 0)
2058 r = sshbuf_put_u8(arg, c);
2062 fatal_fr(r, "sshbuf_put_u8");
2064 if ((i != 0 && (r = sshbuf_put_u8(buf, ' ')) != 0) ||
2065 (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0) ||
2066 (r = sshbuf_putb(buf, arg)) != 0 ||
2067 (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0))
2068 fatal_fr(r, "assemble");
2070 if ((ret = malloc(sshbuf_len(buf) + 1)) == NULL)
2071 fatal_f("malloc failed");
2072 memcpy(ret, sshbuf_ptr(buf), sshbuf_len(buf));
2073 ret[sshbuf_len(buf)] = '\0';
2080 argv_next(int *argcp, char ***argvp)
2082 char *ret = (*argvp)[0];
2084 if (*argcp > 0 && ret != NULL) {
2092 argv_consume(int *argcp)
2098 argv_free(char **av, int ac)
2104 for (i = 0; i < ac; i++)
2109 /* Returns 0 if pid exited cleanly, non-zero otherwise */
2111 exited_cleanly(pid_t pid, const char *tag, const char *cmd, int quiet)
2115 while (waitpid(pid, &status, 0) == -1) {
2116 if (errno != EINTR) {
2117 error("%s waitpid: %s", tag, strerror(errno));
2121 if (WIFSIGNALED(status)) {
2122 error("%s %s exited on signal %d", tag, cmd, WTERMSIG(status));
2124 } else if (WEXITSTATUS(status) != 0) {
2125 do_log2(quiet ? SYSLOG_LEVEL_DEBUG1 : SYSLOG_LEVEL_INFO,
2126 "%s %s failed, status %d", tag, cmd, WEXITSTATUS(status));
2133 * Check a given path for security. This is defined as all components
2134 * of the path to the file must be owned by either the owner of
2135 * of the file or root and no directories must be group or world writable.
2137 * XXX Should any specific check be done for sym links ?
2139 * Takes a file name, its stat information (preferably from fstat() to
2140 * avoid races), the uid of the expected owner, their home directory and an
2141 * error buffer plus max size as arguments.
2143 * Returns 0 on success and -1 on failure
2146 safe_path(const char *name, struct stat *stp, const char *pw_dir,
2147 uid_t uid, char *err, size_t errlen)
2149 char buf[PATH_MAX], homedir[PATH_MAX];
2151 int comparehome = 0;
2154 if (realpath(name, buf) == NULL) {
2155 snprintf(err, errlen, "realpath %s failed: %s", name,
2159 if (pw_dir != NULL && realpath(pw_dir, homedir) != NULL)
2162 if (!S_ISREG(stp->st_mode)) {
2163 snprintf(err, errlen, "%s is not a regular file", buf);
2166 if ((!platform_sys_dir_uid(stp->st_uid) && stp->st_uid != uid) ||
2167 (stp->st_mode & 022) != 0) {
2168 snprintf(err, errlen, "bad ownership or modes for file %s",
2173 /* for each component of the canonical path, walking upwards */
2175 if ((cp = dirname(buf)) == NULL) {
2176 snprintf(err, errlen, "dirname() failed");
2179 strlcpy(buf, cp, sizeof(buf));
2181 if (stat(buf, &st) == -1 ||
2182 (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) ||
2183 (st.st_mode & 022) != 0) {
2184 snprintf(err, errlen,
2185 "bad ownership or modes for directory %s", buf);
2189 /* If are past the homedir then we can stop */
2190 if (comparehome && strcmp(homedir, buf) == 0)
2194 * dirname should always complete with a "/" path,
2195 * but we can be paranoid and check for "." too
2197 if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0))
2204 * Version of safe_path() that accepts an open file descriptor to
2207 * Returns 0 on success and -1 on failure
2210 safe_path_fd(int fd, const char *file, struct passwd *pw,
2211 char *err, size_t errlen)
2215 /* check the open file to avoid races */
2216 if (fstat(fd, &st) == -1) {
2217 snprintf(err, errlen, "cannot stat file %s: %s",
2218 file, strerror(errno));
2221 return safe_path(file, &st, pw->pw_dir, pw->pw_uid, err, errlen);
2225 * Sets the value of the given variable in the environment. If the variable
2226 * already exists, its value is overridden.
2229 child_set_env(char ***envp, u_int *envsizep, const char *name,
2236 if (strchr(name, '=') != NULL) {
2237 error("Invalid environment variable \"%.100s\"", name);
2242 * If we're passed an uninitialized list, allocate a single null
2243 * entry before continuing.
2245 if (*envp == NULL && *envsizep == 0) {
2246 *envp = xmalloc(sizeof(char *));
2252 * Find the slot where the value should be stored. If the variable
2253 * already exists, we reuse the slot; otherwise we append a new slot
2254 * at the end of the array, expanding if necessary.
2257 namelen = strlen(name);
2258 for (i = 0; env[i]; i++)
2259 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
2262 /* Reuse the slot. */
2265 /* New variable. Expand if necessary. */
2266 envsize = *envsizep;
2267 if (i >= envsize - 1) {
2268 if (envsize >= 1000)
2269 fatal("child_set_env: too many env vars");
2271 env = (*envp) = xreallocarray(env, envsize, sizeof(char *));
2272 *envsizep = envsize;
2274 /* Need to set the NULL pointer at end of array beyond the new slot. */
2278 /* Allocate space and format the variable in the appropriate slot. */
2280 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
2281 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
2285 * Check and optionally lowercase a domain name, also removes trailing '.'
2286 * Returns 1 on success and 0 on failure, storing an error message in errstr.
2289 valid_domain(char *name, int makelower, const char **errstr)
2291 size_t i, l = strlen(name);
2292 u_char c, last = '\0';
2293 static char errbuf[256];
2296 strlcpy(errbuf, "empty domain name", sizeof(errbuf));
2299 if (!isalpha((u_char)name[0]) && !isdigit((u_char)name[0])) {
2300 snprintf(errbuf, sizeof(errbuf), "domain name \"%.100s\" "
2301 "starts with invalid character", name);
2304 for (i = 0; i < l; i++) {
2305 c = tolower((u_char)name[i]);
2308 if (last == '.' && c == '.') {
2309 snprintf(errbuf, sizeof(errbuf), "domain name "
2310 "\"%.100s\" contains consecutive separators", name);
2313 if (c != '.' && c != '-' && !isalnum(c) &&
2314 c != '_') /* technically invalid, but common */ {
2315 snprintf(errbuf, sizeof(errbuf), "domain name "
2316 "\"%.100s\" contains invalid characters", name);
2321 if (name[l - 1] == '.')
2333 * Verify that a environment variable name (not including initial '$') is
2334 * valid; consisting of one or more alphanumeric or underscore characters only.
2335 * Returns 1 on valid, 0 otherwise.
2338 valid_env_name(const char *name)
2342 if (name[0] == '\0')
2344 for (cp = name; *cp != '\0'; cp++) {
2345 if (!isalnum((u_char)*cp) && *cp != '_')
2352 atoi_err(const char *nptr, int *val)
2354 const char *errstr = NULL;
2357 if (nptr == NULL || *nptr == '\0')
2359 num = strtonum(nptr, 0, INT_MAX, &errstr);
2366 parse_absolute_time(const char *s, uint64_t *tp)
2375 * POSIX strptime says "The application shall ensure that there
2376 * is white-space or other non-alphanumeric characters between
2377 * any two conversion specifications" so arrange things this way.
2379 switch (strlen(s)) {
2380 case 8: /* YYYYMMDD */
2382 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2s", s, s + 4, s + 6);
2384 case 12: /* YYYYMMDDHHMM */
2385 fmt = "%Y-%m-%dT%H:%M";
2386 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s",
2387 s, s + 4, s + 6, s + 8, s + 10);
2389 case 14: /* YYYYMMDDHHMMSS */
2390 fmt = "%Y-%m-%dT%H:%M:%S";
2391 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s:%.2s",
2392 s, s + 4, s + 6, s + 8, s + 10, s + 12);
2395 return SSH_ERR_INVALID_FORMAT;
2398 memset(&tm, 0, sizeof(tm));
2399 if (strptime(buf, fmt, &tm) == NULL)
2400 return SSH_ERR_INVALID_FORMAT;
2401 if ((tt = mktime(&tm)) < 0)
2402 return SSH_ERR_INVALID_FORMAT;
2408 /* On OpenBSD time_t is int64_t which is long long. */
2409 /* #define SSH_TIME_T_MAX LLONG_MAX */
2412 format_absolute_time(uint64_t t, char *buf, size_t len)
2414 time_t tt = t > SSH_TIME_T_MAX ? SSH_TIME_T_MAX : t;
2417 localtime_r(&tt, &tm);
2418 strftime(buf, len, "%Y-%m-%dT%H:%M:%S", &tm);
2421 /* check if path is absolute */
2423 path_absolute(const char *path)
2425 return (*path == '/') ? 1 : 0;
2429 skip_space(char **cpp)
2433 for (cp = *cpp; *cp == ' ' || *cp == '\t'; cp++)
2438 /* authorized_key-style options parsing helpers */
2441 * Match flag 'opt' in *optsp, and if allow_negate is set then also match
2442 * 'no-opt'. Returns -1 if option not matched, 1 if option matches or 0
2443 * if negated option matches.
2444 * If the option or negated option matches, then *optsp is updated to
2445 * point to the first character after the option.
2448 opt_flag(const char *opt, int allow_negate, const char **optsp)
2450 size_t opt_len = strlen(opt);
2451 const char *opts = *optsp;
2454 if (allow_negate && strncasecmp(opts, "no-", 3) == 0) {
2458 if (strncasecmp(opts, opt, opt_len) == 0) {
2459 *optsp = opts + opt_len;
2460 return negate ? 0 : 1;
2466 opt_dequote(const char **sp, const char **errstrp)
2468 const char *s = *sp;
2474 *errstrp = "missing start quote";
2478 if ((ret = malloc(strlen((s)) + 1)) == NULL) {
2479 *errstrp = "memory allocation failed";
2482 for (i = 0; *s != '\0' && *s != '"';) {
2483 if (s[0] == '\\' && s[1] == '"')
2488 *errstrp = "missing end quote";
2499 opt_match(const char **opts, const char *term)
2501 if (strncasecmp((*opts), term, strlen(term)) == 0 &&
2502 (*opts)[strlen(term)] == '=') {
2503 *opts += strlen(term) + 1;
2510 opt_array_append2(const char *file, const int line, const char *directive,
2511 char ***array, int **iarray, u_int *lp, const char *s, int i)
2515 fatal("%s line %d: Too many %s entries", file, line, directive);
2517 if (iarray != NULL) {
2518 *iarray = xrecallocarray(*iarray, *lp, *lp + 1,
2523 *array = xrecallocarray(*array, *lp, *lp + 1, sizeof(**array));
2524 (*array)[*lp] = xstrdup(s);
2529 opt_array_append(const char *file, const int line, const char *directive,
2530 char ***array, u_int *lp, const char *s)
2532 opt_array_append2(file, line, directive, array, NULL, lp, s, 0);
2536 ssh_signal(int signum, sshsig_t handler)
2538 struct sigaction sa, osa;
2540 /* mask all other signals while in handler */
2541 memset(&sa, 0, sizeof(sa));
2542 sa.sa_handler = handler;
2543 sigfillset(&sa.sa_mask);
2544 #if defined(SA_RESTART) && !defined(NO_SA_RESTART)
2545 if (signum != SIGALRM)
2546 sa.sa_flags = SA_RESTART;
2548 if (sigaction(signum, &sa, &osa) == -1) {
2549 debug3("sigaction(%s): %s", strsignal(signum), strerror(errno));
2552 return osa.sa_handler;
2556 stdfd_devnull(int do_stdin, int do_stdout, int do_stderr)
2558 int devnull, ret = 0;
2560 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
2561 error_f("open %s: %s", _PATH_DEVNULL,
2565 if ((do_stdin && dup2(devnull, STDIN_FILENO) == -1) ||
2566 (do_stdout && dup2(devnull, STDOUT_FILENO) == -1) ||
2567 (do_stderr && dup2(devnull, STDERR_FILENO) == -1)) {
2568 error_f("dup2: %s", strerror(errno));
2571 if (devnull > STDERR_FILENO)
2577 * Runs command in a subprocess with a minimal environment.
2578 * Returns pid on success, 0 on failure.
2579 * The child stdout and stderr maybe captured, left attached or sent to
2580 * /dev/null depending on the contents of flags.
2581 * "tag" is prepended to log messages.
2582 * NB. "command" is only used for logging; the actual command executed is
2586 subprocess(const char *tag, const char *command,
2587 int ac, char **av, FILE **child, u_int flags,
2588 struct passwd *pw, privdrop_fn *drop_privs, privrestore_fn *restore_privs)
2592 int fd, devnull, p[2], i;
2594 char *cp, errmsg[512];
2598 /* If dropping privs, then must specify user and restore function */
2599 if (drop_privs != NULL && (pw == NULL || restore_privs == NULL)) {
2600 error("%s: inconsistent arguments", tag); /* XXX fatal? */
2603 if (pw == NULL && (pw = getpwuid(getuid())) == NULL) {
2604 error("%s: no user for current uid", tag);
2610 debug3_f("%s command \"%s\" running as %s (flags 0x%x)",
2611 tag, command, pw->pw_name, flags);
2613 /* Check consistency */
2614 if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
2615 (flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0) {
2616 error_f("inconsistent flags");
2619 if (((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0) != (child == NULL)) {
2620 error_f("inconsistent flags/output");
2625 * If executing an explicit binary, then verify the it exists
2626 * and appears safe-ish to execute
2628 if (!path_absolute(av[0])) {
2629 error("%s path is not absolute", tag);
2632 if (drop_privs != NULL)
2634 if (stat(av[0], &st) == -1) {
2635 error("Could not stat %s \"%s\": %s", tag,
2636 av[0], strerror(errno));
2637 goto restore_return;
2639 if ((flags & SSH_SUBPROCESS_UNSAFE_PATH) == 0 &&
2640 safe_path(av[0], &st, NULL, 0, errmsg, sizeof(errmsg)) != 0) {
2641 error("Unsafe %s \"%s\": %s", tag, av[0], errmsg);
2642 goto restore_return;
2644 /* Prepare to keep the child's stdout if requested */
2645 if (pipe(p) == -1) {
2646 error("%s: pipe: %s", tag, strerror(errno));
2648 if (restore_privs != NULL)
2652 if (restore_privs != NULL)
2655 switch ((pid = fork())) {
2656 case -1: /* error */
2657 error("%s: fork: %s", tag, strerror(errno));
2662 /* Prepare a minimal environment for the child. */
2663 if ((flags & SSH_SUBPROCESS_PRESERVE_ENV) == 0) {
2665 env = xcalloc(sizeof(*env), nenv);
2666 child_set_env(&env, &nenv, "PATH", _PATH_STDPATH);
2667 child_set_env(&env, &nenv, "USER", pw->pw_name);
2668 child_set_env(&env, &nenv, "LOGNAME", pw->pw_name);
2669 child_set_env(&env, &nenv, "HOME", pw->pw_dir);
2670 if ((cp = getenv("LANG")) != NULL)
2671 child_set_env(&env, &nenv, "LANG", cp);
2674 for (i = 1; i < NSIG; i++)
2675 ssh_signal(i, SIG_DFL);
2677 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
2678 error("%s: open %s: %s", tag, _PATH_DEVNULL,
2682 if (dup2(devnull, STDIN_FILENO) == -1) {
2683 error("%s: dup2: %s", tag, strerror(errno));
2687 /* Set up stdout as requested; leave stderr in place for now. */
2689 if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0)
2691 else if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0)
2693 if (fd != -1 && dup2(fd, STDOUT_FILENO) == -1) {
2694 error("%s: dup2: %s", tag, strerror(errno));
2697 closefrom(STDERR_FILENO + 1);
2699 if (geteuid() == 0 &&
2700 initgroups(pw->pw_name, pw->pw_gid) == -1) {
2701 error("%s: initgroups(%s, %u): %s", tag,
2702 pw->pw_name, (u_int)pw->pw_gid, strerror(errno));
2705 if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) {
2706 error("%s: setresgid %u: %s", tag, (u_int)pw->pw_gid,
2710 if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1) {
2711 error("%s: setresuid %u: %s", tag, (u_int)pw->pw_uid,
2715 /* stdin is pointed to /dev/null at this point */
2716 if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 &&
2717 dup2(STDIN_FILENO, STDERR_FILENO) == -1) {
2718 error("%s: dup2: %s", tag, strerror(errno));
2722 execve(av[0], av, env);
2725 error("%s %s \"%s\": %s", tag, env == NULL ? "execv" : "execve",
2726 command, strerror(errno));
2728 default: /* parent */
2733 if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0)
2735 else if ((f = fdopen(p[0], "r")) == NULL) {
2736 error("%s: fdopen: %s", tag, strerror(errno));
2738 /* Don't leave zombie child */
2740 while (waitpid(pid, NULL, 0) == -1 && errno == EINTR)
2745 debug3_f("%s pid %ld", tag, (long)pid);
2752 lookup_env_in_list(const char *env, char * const *envs, size_t nenvs)
2756 envlen = strlen(env);
2757 for (i = 0; i < nenvs; i++) {
2758 if (strncmp(envs[i], env, envlen) == 0 &&
2759 envs[i][envlen] == '=') {
2760 return envs[i] + envlen + 1;