=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/misc.c,v retrieving revision 1.29 retrieving revision 1.29.2.2 diff -u -r1.29 -r1.29.2.2 --- src/usr.bin/ssh/misc.c 2005/03/10 22:01:05 1.29 +++ src/usr.bin/ssh/misc.c 2006/02/03 02:53:44 1.29.2.2 @@ -1,5 +1,6 @@ /* * 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 @@ -23,8 +24,10 @@ */ #include "includes.h" -RCSID("$OpenBSD: misc.c,v 1.29 2005/03/10 22:01:05 deraadt Exp $"); +RCSID("$OpenBSD: misc.c,v 1.29.2.2 2006/02/03 02:53:44 brad Exp $"); +#include + #include "misc.h" #include "log.h" #include "xmalloc.h" @@ -187,6 +190,37 @@ 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) @@ -349,12 +383,15 @@ addargs(arglist *args, char *fmt, ...) { va_list ap; - char buf[1024]; + char *cp; u_int nalloc; + int r; va_start(ap, fmt); - vsnprintf(buf, sizeof(buf), fmt, ap); + r = vasprintf(&cp, fmt, ap); va_end(ap); + if (r == -1) + fatal("addargs: argument too long"); nalloc = args->nalloc; if (args->list == NULL) { @@ -365,11 +402,153 @@ args->list = xrealloc(args->list, nalloc * sizeof(char *)); args->nalloc = nalloc; - args->list[args->num++] = xstrdup(buf); + args->list[args->num++] = cp; args->list[args->num] = NULL; } +void +replacearg(arglist *args, u_int which, char *fmt, ...) +{ + va_list ap; + char *cp; + int r; + + va_start(ap, fmt); + r = vasprintf(&cp, fmt, ap); + va_end(ap); + if (r == -1) + fatal("replacearg: argument too long"); + + if (which >= args->num) + fatal("replacearg: tried to replace invalid arg %d >= %d", + which, args->num); + xfree(args->list[which]); + args->list[which] = cp; +} + +void +freeargs(arglist *args) +{ + u_int i; + + if (args->list != NULL) { + for (i = 0; i < args->num; i++) + xfree(args->list[i]); + xfree(args->list); + args->nalloc = args->num = 0; + args->list = 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. */ @@ -391,3 +570,106 @@ } return -1; } + +int +tun_open(int tun, int mode) +{ + 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", __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; + + /* Set interface mode */ + ifr.ifr_flags &= ~IFF_UP; + if (mode == SSH_TUNMODE_ETHERNET) + ifr.ifr_flags |= IFF_LINK0; + else + ifr.ifr_flags &= ~IFF_LINK0; + if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) + goto failed; + + /* Bring interface up */ + 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); +} + +void +sanitise_stdfd(void) +{ + int nullfd, dupfd; + + if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) { + fprintf(stderr, "Couldn't open /dev/null: %s", strerror(errno)); + exit(1); + } + while (++dupfd <= 2) { + /* Only clobber closed fds */ + if (fcntl(dupfd, F_GETFL, 0) >= 0) + continue; + if (dup2(nullfd, dupfd) == -1) { + fprintf(stderr, "dup2: %s", strerror(errno)); + exit(1); + } + } + 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); +} +