| /* |
| * Copyright (c) 2000 Markus Friedl. All rights reserved. |
| * Copyright (c) 2005 Damien Miller. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "includes.h" |
| RCSID("$OpenBSD: misc.c,v 1.38 2006/01/01 08:59:27 stevesk Exp $"); |
| |
| #ifdef SSH_TUN_OPENBSD |
| #include <net/if.h> |
| #endif |
| |
| #include "misc.h" |
| #include "log.h" |
| #include "xmalloc.h" |
| |
| /* remove newline at end of string */ |
| char * |
| chop(char *s) |
| { |
| char *t = s; |
| while (*t) { |
| if (*t == '\n' || *t == '\r') { |
| *t = '\0'; |
| return s; |
| } |
| t++; |
| } |
| return s; |
| |
| } |
| |
| /* set/unset filedescriptor to non-blocking */ |
| int |
| set_nonblock(int fd) |
| { |
| int val; |
| |
| val = fcntl(fd, F_GETFL, 0); |
| if (val < 0) { |
| error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno)); |
| return (-1); |
| } |
| if (val & O_NONBLOCK) { |
| debug3("fd %d is O_NONBLOCK", fd); |
| return (0); |
| } |
| debug2("fd %d setting O_NONBLOCK", fd); |
| val |= O_NONBLOCK; |
| if (fcntl(fd, F_SETFL, val) == -1) { |
| debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd, |
| strerror(errno)); |
| return (-1); |
| } |
| return (0); |
| } |
| |
| int |
| unset_nonblock(int fd) |
| { |
| int val; |
| |
| val = fcntl(fd, F_GETFL, 0); |
| if (val < 0) { |
| error("fcntl(%d, F_GETFL, 0): %s", fd, strerror(errno)); |
| return (-1); |
| } |
| if (!(val & O_NONBLOCK)) { |
| debug3("fd %d is not O_NONBLOCK", fd); |
| return (0); |
| } |
| debug("fd %d clearing O_NONBLOCK", fd); |
| val &= ~O_NONBLOCK; |
| if (fcntl(fd, F_SETFL, val) == -1) { |
| debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s", |
| fd, strerror(errno)); |
| return (-1); |
| } |
| return (0); |
| } |
| |
| /* disable nagle on socket */ |
| void |
| set_nodelay(int fd) |
| { |
| int opt; |
| socklen_t optlen; |
| |
| optlen = sizeof opt; |
| if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) { |
| debug("getsockopt TCP_NODELAY: %.100s", strerror(errno)); |
| return; |
| } |
| if (opt == 1) { |
| debug2("fd %d is TCP_NODELAY", fd); |
| return; |
| } |
| opt = 1; |
| debug2("fd %d setting TCP_NODELAY", fd); |
| if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1) |
| error("setsockopt TCP_NODELAY: %.100s", strerror(errno)); |
| } |
| |
| /* Characters considered whitespace in strsep calls. */ |
| #define WHITESPACE " \t\r\n" |
| |
| /* return next token in configuration line */ |
| char * |
| strdelim(char **s) |
| { |
| char *old; |
| int wspace = 0; |
| |
| if (*s == NULL) |
| return NULL; |
| |
| old = *s; |
| |
| *s = strpbrk(*s, WHITESPACE "="); |
| if (*s == NULL) |
| return (old); |
| |
| /* Allow only one '=' to be skipped */ |
| if (*s[0] == '=') |
| wspace = 1; |
| *s[0] = '\0'; |
| |
| *s += strspn(*s + 1, WHITESPACE) + 1; |
| if (*s[0] == '=' && !wspace) |
| *s += strspn(*s + 1, WHITESPACE) + 1; |
| |
| return (old); |
| } |
| |
| struct passwd * |
| pwcopy(struct passwd *pw) |
| { |
| struct passwd *copy = xmalloc(sizeof(*copy)); |
| |
| memset(copy, 0, sizeof(*copy)); |
| copy->pw_name = xstrdup(pw->pw_name); |
| copy->pw_passwd = xstrdup(pw->pw_passwd); |
| copy->pw_gecos = xstrdup(pw->pw_gecos); |
| copy->pw_uid = pw->pw_uid; |
| copy->pw_gid = pw->pw_gid; |
| #ifdef HAVE_PW_EXPIRE_IN_PASSWD |
| copy->pw_expire = pw->pw_expire; |
| #endif |
| #ifdef HAVE_PW_CHANGE_IN_PASSWD |
| copy->pw_change = pw->pw_change; |
| #endif |
| #ifdef HAVE_PW_CLASS_IN_PASSWD |
| copy->pw_class = xstrdup(pw->pw_class); |
| #endif |
| copy->pw_dir = xstrdup(pw->pw_dir); |
| copy->pw_shell = xstrdup(pw->pw_shell); |
| return copy; |
| } |
| |
| /* |
| * Convert ASCII string to TCP/IP port number. |
| * Port must be >0 and <=65535. |
| * Return 0 if invalid. |
| */ |
| int |
| a2port(const char *s) |
| { |
| long port; |
| char *endp; |
| |
| errno = 0; |
| port = strtol(s, &endp, 0); |
| if (s == endp || *endp != '\0' || |
| (errno == ERANGE && (port == LONG_MIN || port == LONG_MAX)) || |
| port <= 0 || port > 65535) |
| return 0; |
| |
| return port; |
| } |
| |
| int |
| a2tun(const char *s, int *remote) |
| { |
| const char *errstr = NULL; |
| char *sp, *ep; |
| int tun; |
| |
| if (remote != NULL) { |
| *remote = SSH_TUNID_ANY; |
| sp = xstrdup(s); |
| if ((ep = strchr(sp, ':')) == NULL) { |
| xfree(sp); |
| return (a2tun(s, NULL)); |
| } |
| ep[0] = '\0'; ep++; |
| *remote = a2tun(ep, NULL); |
| tun = a2tun(sp, NULL); |
| xfree(sp); |
| return (*remote == SSH_TUNID_ERR ? *remote : tun); |
| } |
| |
| if (strcasecmp(s, "any") == 0) |
| return (SSH_TUNID_ANY); |
| |
| tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr); |
| if (errstr != NULL) |
| return (SSH_TUNID_ERR); |
| |
| return (tun); |
| } |
| |
| #define SECONDS 1 |
| #define MINUTES (SECONDS * 60) |
| #define HOURS (MINUTES * 60) |
| #define DAYS (HOURS * 24) |
| #define WEEKS (DAYS * 7) |
| |
| /* |
| * Convert a time string into seconds; format is |
| * a sequence of: |
| * time[qualifier] |
| * |
| * Valid time qualifiers are: |
| * <none> seconds |
| * s|S seconds |
| * m|M minutes |
| * h|H hours |
| * d|D days |
| * w|W weeks |
| * |
| * Examples: |
| * 90m 90 minutes |
| * 1h30m 90 minutes |
| * 2d 2 days |
| * 1w 1 week |
| * |
| * Return -1 if time string is invalid. |
| */ |
| long |
| convtime(const char *s) |
| { |
| long total, secs; |
| const char *p; |
| char *endp; |
| |
| errno = 0; |
| total = 0; |
| p = s; |
| |
| if (p == NULL || *p == '\0') |
| return -1; |
| |
| while (*p) { |
| secs = strtol(p, &endp, 10); |
| if (p == endp || |
| (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) || |
| secs < 0) |
| return -1; |
| |
| switch (*endp++) { |
| case '\0': |
| endp--; |
| case 's': |
| case 'S': |
| break; |
| case 'm': |
| case 'M': |
| secs *= MINUTES; |
| break; |
| case 'h': |
| case 'H': |
| secs *= HOURS; |
| break; |
| case 'd': |
| case 'D': |
| secs *= DAYS; |
| break; |
| case 'w': |
| case 'W': |
| secs *= WEEKS; |
| break; |
| default: |
| return -1; |
| } |
| total += secs; |
| if (total < 0) |
| return -1; |
| p = endp; |
| } |
| |
| return total; |
| } |
| |
| /* |
| * Search for next delimiter between hostnames/addresses and ports. |
| * Argument may be modified (for termination). |
| * Returns *cp if parsing succeeds. |
| * *cp is set to the start of the next delimiter, if one was found. |
| * If this is the last field, *cp is set to NULL. |
| */ |
| char * |
| hpdelim(char **cp) |
| { |
| char *s, *old; |
| |
| if (cp == NULL || *cp == NULL) |
| return NULL; |
| |
| old = s = *cp; |
| if (*s == '[') { |
| if ((s = strchr(s, ']')) == NULL) |
| return NULL; |
| else |
| s++; |
| } else if ((s = strpbrk(s, ":/")) == NULL) |
| s = *cp + strlen(*cp); /* skip to end (see first case below) */ |
| |
| switch (*s) { |
| case '\0': |
| *cp = NULL; /* no more fields*/ |
| break; |
| |
| case ':': |
| case '/': |
| *s = '\0'; /* terminate */ |
| *cp = s + 1; |
| break; |
| |
| default: |
| return NULL; |
| } |
| |
| return old; |
| } |
| |
| char * |
| cleanhostname(char *host) |
| { |
| if (*host == '[' && host[strlen(host) - 1] == ']') { |
| host[strlen(host) - 1] = '\0'; |
| return (host + 1); |
| } else |
| return host; |
| } |
| |
| char * |
| colon(char *cp) |
| { |
| int flag = 0; |
| |
| if (*cp == ':') /* Leading colon is part of file name. */ |
| return (0); |
| if (*cp == '[') |
| flag = 1; |
| |
| for (; *cp; ++cp) { |
| if (*cp == '@' && *(cp+1) == '[') |
| flag = 1; |
| if (*cp == ']' && *(cp+1) == ':' && flag) |
| return (cp+1); |
| if (*cp == ':' && !flag) |
| return (cp); |
| if (*cp == '/') |
| return (0); |
| } |
| return (0); |
| } |
| |
| /* function to assist building execv() arguments */ |
| void |
| addargs(arglist *args, char *fmt, ...) |
| { |
| va_list ap; |
| char buf[1024]; |
| u_int nalloc; |
| |
| va_start(ap, fmt); |
| vsnprintf(buf, sizeof(buf), fmt, ap); |
| va_end(ap); |
| |
| nalloc = args->nalloc; |
| if (args->list == NULL) { |
| nalloc = 32; |
| args->num = 0; |
| } else if (args->num+2 >= nalloc) |
| nalloc *= 2; |
| |
| args->list = xrealloc(args->list, nalloc * sizeof(char *)); |
| args->nalloc = nalloc; |
| args->list[args->num++] = xstrdup(buf); |
| args->list[args->num] = NULL; |
| } |
| |
| /* |
| * Expands tildes in the file name. Returns data allocated by xmalloc. |
| * Warning: this calls getpw*. |
| */ |
| char * |
| tilde_expand_filename(const char *filename, uid_t uid) |
| { |
| const char *path; |
| char user[128], ret[MAXPATHLEN]; |
| struct passwd *pw; |
| u_int len, slash; |
| |
| if (*filename != '~') |
| return (xstrdup(filename)); |
| filename++; |
| |
| path = strchr(filename, '/'); |
| if (path != NULL && path > filename) { /* ~user/path */ |
| slash = path - filename; |
| if (slash > sizeof(user) - 1) |
| fatal("tilde_expand_filename: ~username too long"); |
| memcpy(user, filename, slash); |
| user[slash] = '\0'; |
| if ((pw = getpwnam(user)) == NULL) |
| fatal("tilde_expand_filename: No such user %s", user); |
| } else if ((pw = getpwuid(uid)) == NULL) /* ~/path */ |
| fatal("tilde_expand_filename: No such uid %d", uid); |
| |
| if (strlcpy(ret, pw->pw_dir, sizeof(ret)) >= sizeof(ret)) |
| fatal("tilde_expand_filename: Path too long"); |
| |
| /* Make sure directory has a trailing '/' */ |
| len = strlen(pw->pw_dir); |
| if ((len == 0 || pw->pw_dir[len - 1] != '/') && |
| strlcat(ret, "/", sizeof(ret)) >= sizeof(ret)) |
| fatal("tilde_expand_filename: Path too long"); |
| |
| /* Skip leading '/' from specified path */ |
| if (path != NULL) |
| filename = path + 1; |
| if (strlcat(ret, filename, sizeof(ret)) >= sizeof(ret)) |
| fatal("tilde_expand_filename: Path too long"); |
| |
| return (xstrdup(ret)); |
| } |
| |
| /* |
| * Expand a string with a set of %[char] escapes. A number of escapes may be |
| * specified as (char *escape_chars, char *replacement) pairs. The list must |
| * be terminated by a NULL escape_char. Returns replaced string in memory |
| * allocated by xmalloc. |
| */ |
| char * |
| percent_expand(const char *string, ...) |
| { |
| #define EXPAND_MAX_KEYS 16 |
| struct { |
| const char *key; |
| const char *repl; |
| } keys[EXPAND_MAX_KEYS]; |
| u_int num_keys, i, j; |
| char buf[4096]; |
| va_list ap; |
| |
| /* Gather keys */ |
| va_start(ap, string); |
| for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) { |
| keys[num_keys].key = va_arg(ap, char *); |
| if (keys[num_keys].key == NULL) |
| break; |
| keys[num_keys].repl = va_arg(ap, char *); |
| if (keys[num_keys].repl == NULL) |
| fatal("percent_expand: NULL replacement"); |
| } |
| va_end(ap); |
| |
| if (num_keys >= EXPAND_MAX_KEYS) |
| fatal("percent_expand: too many keys"); |
| |
| /* Expand string */ |
| *buf = '\0'; |
| for (i = 0; *string != '\0'; string++) { |
| if (*string != '%') { |
| append: |
| buf[i++] = *string; |
| if (i >= sizeof(buf)) |
| fatal("percent_expand: string too long"); |
| buf[i] = '\0'; |
| continue; |
| } |
| string++; |
| if (*string == '%') |
| goto append; |
| for (j = 0; j < num_keys; j++) { |
| if (strchr(keys[j].key, *string) != NULL) { |
| i = strlcat(buf, keys[j].repl, sizeof(buf)); |
| if (i >= sizeof(buf)) |
| fatal("percent_expand: string too long"); |
| break; |
| } |
| } |
| if (j >= num_keys) |
| fatal("percent_expand: unknown key %%%c", *string); |
| } |
| return (xstrdup(buf)); |
| #undef EXPAND_MAX_KEYS |
| } |
| |
| /* |
| * Read an entire line from a public key file into a static buffer, discarding |
| * lines that exceed the buffer size. Returns 0 on success, -1 on failure. |
| */ |
| int |
| read_keyfile_line(FILE *f, const char *filename, char *buf, size_t bufsz, |
| u_long *lineno) |
| { |
| while (fgets(buf, bufsz, f) != NULL) { |
| (*lineno)++; |
| if (buf[strlen(buf) - 1] == '\n' || feof(f)) { |
| return 0; |
| } else { |
| debug("%s: %s line %lu exceeds size limit", __func__, |
| filename, *lineno); |
| /* discard remainder of line */ |
| while (fgetc(f) != '\n' && !feof(f)) |
| ; /* nothing */ |
| } |
| } |
| return -1; |
| } |
| |
| int |
| tun_open(int tun, int mode) |
| { |
| #if defined(CUSTOM_SYS_TUN_OPEN) |
| return (sys_tun_open(tun, mode)); |
| #elif defined(SSH_TUN_OPENBSD) |
| struct ifreq ifr; |
| char name[100]; |
| int fd = -1, sock; |
| |
| /* Open the tunnel device */ |
| if (tun <= SSH_TUNID_MAX) { |
| snprintf(name, sizeof(name), "/dev/tun%d", tun); |
| fd = open(name, O_RDWR); |
| } else if (tun == SSH_TUNID_ANY) { |
| for (tun = 100; tun >= 0; tun--) { |
| snprintf(name, sizeof(name), "/dev/tun%d", tun); |
| if ((fd = open(name, O_RDWR)) >= 0) |
| break; |
| } |
| } else { |
| debug("%s: invalid tunnel %u\n", __func__, tun); |
| return (-1); |
| } |
| |
| if (fd < 0) { |
| debug("%s: %s open failed: %s", __func__, name, strerror(errno)); |
| return (-1); |
| } |
| |
| debug("%s: %s mode %d fd %d", __func__, name, mode, fd); |
| |
| /* Set the tunnel device operation mode */ |
| snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "tun%d", tun); |
| if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1) |
| goto failed; |
| |
| if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) |
| goto failed; |
| if (mode == SSH_TUNMODE_ETHERNET) { |
| ifr.ifr_flags |= IFF_LINK0; |
| if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) |
| goto failed; |
| } |
| ifr.ifr_flags |= IFF_UP; |
| if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) |
| goto failed; |
| |
| close(sock); |
| return (fd); |
| |
| failed: |
| if (fd >= 0) |
| close(fd); |
| if (sock >= 0) |
| close(sock); |
| debug("%s: failed to set %s mode %d: %s", __func__, name, |
| mode, strerror(errno)); |
| return (-1); |
| #else |
| error("Tunnel interfaces are not supported on this platform"); |
| return (-1); |
| #endif |
| } |
| |
| void |
| sanitise_stdfd(void) |
| { |
| int nullfd; |
| |
| if ((nullfd = open(_PATH_DEVNULL, O_RDWR)) == -1) { |
| fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno)); |
| exit(1); |
| } |
| while (nullfd < 2) { |
| if (dup2(nullfd, nullfd + 1) == -1) { |
| fprintf(stderr, "dup2: %s", strerror(errno)); |
| exit(1); |
| } |
| nullfd++; |
| } |
| if (nullfd > 2) |
| close(nullfd); |
| } |
| |
| char * |
| tohex(const u_char *d, u_int l) |
| { |
| char b[3], *r; |
| u_int i, hl; |
| |
| hl = l * 2 + 1; |
| r = xmalloc(hl); |
| *r = '\0'; |
| for (i = 0; i < l; i++) { |
| snprintf(b, sizeof(b), "%02x", d[i]); |
| strlcat(r, b, hl); |
| } |
| return (r); |
| } |
| |