static void load_public_identity_files(void) { char *filename, *cp, thishost[NI_MAXHOST]; char *pwdir = NULL, *pwname = NULL; int i = 0; Key *public; struct passwd *pw; #ifdef SMARTCARD Key **keys; if (options.smartcard_device != NULL && options.num_identity_files < SSH_MAX_IDENTITY_FILES && (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL) { int count = 0; for (i = 0; keys[i] != NULL; i++) { count++; memmove(&options.identity_files[1], &options.identity_files[0], sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1)); memmove(&options.identity_keys[1], &options.identity_keys[0], sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1)); options.num_identity_files++; options.identity_keys[0] = keys[i]; options.identity_files[0] = sc_get_key_label(keys[i]); } if (options.num_identity_files > SSH_MAX_IDENTITY_FILES) options.num_identity_files = SSH_MAX_IDENTITY_FILES; i = count; xfree(keys); } #endif /* SMARTCARD */ if ((pw = getpwuid(original_real_uid)) == NULL) fatal("load_public_identity_files: getpwuid failed"); pwname = xstrdup(pw->pw_name); pwdir = xstrdup(pw->pw_dir); if (gethostname(thishost, sizeof(thishost)) == -1) fatal("load_public_identity_files: gethostname: %s", strerror(errno)); for (; i < options.num_identity_files; i++) { cp = tilde_expand_filename(options.identity_files[i], original_real_uid); filename = percent_expand(cp, "d", pwdir, "u", pwname, "l", thishost, "h", host, "r", options.user, (char *)NULL); xfree(cp); public = key_load_public(filename, NULL); debug("identity file %s type %d", filename, public ? public->type : -1); xfree(options.identity_files[i]); options.identity_files[i] = filename; options.identity_keys[i] = public; }
/* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */ static void tilde_expand_paths(char **paths, u_int num_paths) { u_int i; char *cp; for (i = 0; i < num_paths; i++) { cp = tilde_expand_filename(paths[i], original_real_uid); xfree(paths[i]); paths[i] = cp; } }
/* return ok if key exists in sysfile or userfile */ HostStatus check_key_in_hostfiles(struct passwd *pw, struct sshkey *key, const char *host, const char *sysfile, const char *userfile) { char *user_hostfile; struct stat st; HostStatus host_status; struct hostkeys *hostkeys; const struct hostkey_entry *found; hostkeys = init_hostkeys(); load_hostkeys(hostkeys, host, sysfile); if (userfile != NULL) { user_hostfile = tilde_expand_filename(userfile, pw->pw_uid); if (options.strict_modes && (stat(user_hostfile, &st) == 0) && ((st.st_uid != 0 && st.st_uid != pw->pw_uid) || (st.st_mode & 022) != 0)) { logit("Authentication refused for %.100s: " "bad owner or modes for %.200s", pw->pw_name, user_hostfile); auth_debug_add("Ignored %.200s: bad ownership or modes", user_hostfile); } else { temporarily_use_uid(pw); load_hostkeys(hostkeys, host, user_hostfile); restore_uid(); } free(user_hostfile); } host_status = check_key_in_hostkeys(hostkeys, key, &found); if (host_status == HOST_REVOKED) error("WARNING: revoked key for %s attempted authentication", found->host); else if (host_status == HOST_OK) debug("%s: key for %s found at %s:%ld", __func__, found->host, found->file, found->line); else debug("%s: key for host %s not found", __func__, host); free_hostkeys(hostkeys); return host_status; }
/* return ok if key exists in sysfile or userfile */ HostStatus check_key_in_hostfiles(struct passwd *pw, Key *key, const char *host, const char *sysfile, const char *userfile) { Key *found; char *user_hostfile; struct stat st; HostStatus host_status; /* Check if we know the host and its host key. */ found = key_new(key->type); host_status = check_host_in_hostfile(sysfile, host, key, found, NULL); if (host_status != HOST_OK && userfile != NULL) { user_hostfile = tilde_expand_filename(userfile, pw->pw_uid); if (options.strict_modes && (stat(user_hostfile, &st) == 0) && ((st.st_uid != 0 && st.st_uid != pw->pw_uid) || (st.st_mode & 022) != 0)) { logit("Authentication refused for %.100s: " "bad owner or modes for %.200s", pw->pw_name, user_hostfile); } else { temporarily_use_uid(pw); host_status = check_host_in_hostfile(user_hostfile, host, key, found, NULL); restore_uid(); } xfree(user_hostfile); } key_free(found); debug2("check_key_in_hostfiles: key %s for %s", host_status == HOST_OK ? "ok" : "not found", host); return host_status; }
/* * Main program for the ssh client. */ int main(int ac, char **av) { int i, r, opt, exit_status, use_syslog; char *p, *cp, *line, *argv0, buf[MAXPATHLEN], *host_arg; char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV]; struct stat st; struct passwd *pw; int dummy, timeout_ms; extern int optind, optreset; extern char *optarg; struct servent *sp; Forward fwd; /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ sanitise_stdfd(); __progname = ssh_get_progname(av[0]); #ifndef HAVE_SETPROCTITLE /* Prepare for later setproctitle emulation */ /* Save argv so it isn't clobbered by setproctitle() emulation */ saved_av = xcalloc(ac + 1, sizeof(*saved_av)); for (i = 0; i < ac; i++) saved_av[i] = xstrdup(av[i]); saved_av[i] = NULL; compat_init_setproctitle(ac, av); av = saved_av; #endif /* * Discard other fds that are hanging around. These can cause problem * with backgrounded ssh processes started by ControlPersist. */ closefrom(STDERR_FILENO + 1); /* * Save the original real uid. It will be needed later (uid-swapping * may clobber the real uid). */ original_real_uid = getuid(); original_effective_uid = geteuid(); /* * Use uid-swapping to give up root privileges for the duration of * option processing. We will re-instantiate the rights when we are * ready to create the privileged port, and will permanently drop * them when the port has been created (actually, when the connection * has been made, as we may need to create the port several times). */ PRIV_END; #ifdef HAVE_SETRLIMIT /* If we are installed setuid root be careful to not drop core. */ if (original_real_uid != original_effective_uid) { struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 0; if (setrlimit(RLIMIT_CORE, &rlim) < 0) fatal("setrlimit failed: %.100s", strerror(errno)); } #endif /* Get user data. */ pw = getpwuid(original_real_uid); if (!pw) { logit("You don't exist, go away!"); exit(255); } /* Take a copy of the returned structure. */ pw = pwcopy(pw); /* * Set our umask to something reasonable, as some files are created * with the default umask. This will make them world-readable but * writable only by the owner, which is ok for all files for which we * don't set the modes explicitly. */ umask(022); /* * Initialize option structure to indicate that no values have been * set. */ initialize_options(&options); /* Parse command-line arguments. */ host = NULL; use_syslog = 0; argv0 = av[0]; again: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx" "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) { switch (opt) { case '1': options.protocol = SSH_PROTO_1; break; case '2': options.protocol = SSH_PROTO_2; break; case '4': options.address_family = AF_INET; break; case '6': options.address_family = AF_INET6; break; case 'n': stdin_null_flag = 1; break; case 'f': fork_after_authentication_flag = 1; stdin_null_flag = 1; break; case 'x': options.forward_x11 = 0; break; case 'X': options.forward_x11 = 1; break; case 'y': use_syslog = 1; break; case 'Y': options.forward_x11 = 1; options.forward_x11_trusted = 1; break; case 'g': options.gateway_ports = 1; break; case 'O': if (stdio_forward_host != NULL) fatal("Cannot specify multiplexing " "command with -W"); else if (muxclient_command != 0) fatal("Multiplexing command already specified"); if (strcmp(optarg, "check") == 0) muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK; else if (strcmp(optarg, "forward") == 0) muxclient_command = SSHMUX_COMMAND_FORWARD; else if (strcmp(optarg, "exit") == 0) muxclient_command = SSHMUX_COMMAND_TERMINATE; else if (strcmp(optarg, "stop") == 0) muxclient_command = SSHMUX_COMMAND_STOP; else if (strcmp(optarg, "cancel") == 0) muxclient_command = SSHMUX_COMMAND_CANCEL_FWD; else fatal("Invalid multiplex command."); break; case 'P': /* deprecated */ options.use_privileged_port = 0; break; case 'a': options.forward_agent = 0; break; case 'A': options.forward_agent = 1; break; case 'k': options.gss_deleg_creds = 0; break; case 'K': options.gss_authentication = 1; options.gss_deleg_creds = 1; break; case 'i': if (stat(optarg, &st) < 0) { fprintf(stderr, "Warning: Identity file %s " "not accessible: %s.\n", optarg, strerror(errno)); break; } if (options.num_identity_files >= SSH_MAX_IDENTITY_FILES) fatal("Too many identity files specified " "(max %d)", SSH_MAX_IDENTITY_FILES); options.identity_files[options.num_identity_files++] = xstrdup(optarg); break; case 'I': #ifdef ENABLE_PKCS11 options.pkcs11_provider = xstrdup(optarg); #else fprintf(stderr, "no support for PKCS#11.\n"); #endif break; case 't': if (options.request_tty == REQUEST_TTY_YES) options.request_tty = REQUEST_TTY_FORCE; else options.request_tty = REQUEST_TTY_YES; break; case 'v': if (debug_flag == 0) { debug_flag = 1; options.log_level = SYSLOG_LEVEL_DEBUG1; } else { if (options.log_level < SYSLOG_LEVEL_DEBUG3) options.log_level++; break; } /* FALLTHROUGH */ case 'V': fprintf(stderr, "%s, %s\n", SSH_RELEASE, SSLeay_version(SSLEAY_VERSION)); if (opt == 'V') exit(0); break; case 'w': if (options.tun_open == -1) options.tun_open = SSH_TUNMODE_DEFAULT; options.tun_local = a2tun(optarg, &options.tun_remote); if (options.tun_local == SSH_TUNID_ERR) { fprintf(stderr, "Bad tun device '%s'\n", optarg); exit(255); } break; case 'W': if (stdio_forward_host != NULL) fatal("stdio forward already specified"); if (muxclient_command != 0) fatal("Cannot specify stdio forward with -O"); if (parse_forward(&fwd, optarg, 1, 0)) { stdio_forward_host = fwd.listen_host; stdio_forward_port = fwd.listen_port; xfree(fwd.connect_host); } else { fprintf(stderr, "Bad stdio forwarding specification '%s'\n", optarg); exit(255); } options.request_tty = REQUEST_TTY_NO; no_shell_flag = 1; options.clear_forwardings = 1; options.exit_on_forward_failure = 1; break; case 'q': options.log_level = SYSLOG_LEVEL_QUIET; break; case 'e': if (optarg[0] == '^' && optarg[2] == 0 && (u_char) optarg[1] >= 64 && (u_char) optarg[1] < 128) options.escape_char = (u_char) optarg[1] & 31; else if (strlen(optarg) == 1) options.escape_char = (u_char) optarg[0]; else if (strcmp(optarg, "none") == 0) options.escape_char = SSH_ESCAPECHAR_NONE; else { fprintf(stderr, "Bad escape character '%s'.\n", optarg); exit(255); } break; case 'c': if (ciphers_valid(optarg)) { /* SSH2 only */ options.ciphers = xstrdup(optarg); options.cipher = SSH_CIPHER_INVALID; } else { /* SSH1 only */ options.cipher = cipher_number(optarg); if (options.cipher == -1) { fprintf(stderr, "Unknown cipher type '%s'\n", optarg); exit(255); } if (options.cipher == SSH_CIPHER_3DES) options.ciphers = "3des-cbc"; else if (options.cipher == SSH_CIPHER_BLOWFISH) options.ciphers = "blowfish-cbc"; else options.ciphers = (char *)-1; } break; case 'm': if (mac_valid(optarg)) options.macs = xstrdup(optarg); else { fprintf(stderr, "Unknown mac type '%s'\n", optarg); exit(255); } break; case 'M': if (options.control_master == SSHCTL_MASTER_YES) options.control_master = SSHCTL_MASTER_ASK; else options.control_master = SSHCTL_MASTER_YES; break; case 'p': options.port = a2port(optarg); if (options.port <= 0) { fprintf(stderr, "Bad port '%s'\n", optarg); exit(255); } break; case 'l': options.user = optarg; break; case 'L': if (parse_forward(&fwd, optarg, 0, 0)) add_local_forward(&options, &fwd); else { fprintf(stderr, "Bad local forwarding specification '%s'\n", optarg); exit(255); } break; case 'R': if (parse_forward(&fwd, optarg, 0, 1)) { add_remote_forward(&options, &fwd); } else { fprintf(stderr, "Bad remote forwarding specification " "'%s'\n", optarg); exit(255); } break; case 'D': if (parse_forward(&fwd, optarg, 1, 0)) { add_local_forward(&options, &fwd); } else { fprintf(stderr, "Bad dynamic forwarding specification " "'%s'\n", optarg); exit(255); } break; case 'C': options.compression = 1; break; case 'N': no_shell_flag = 1; options.request_tty = REQUEST_TTY_NO; break; case 'T': options.request_tty = REQUEST_TTY_NO; break; case 'o': dummy = 1; line = xstrdup(optarg); if (process_config_line(&options, host ? host : "", line, "command-line", 0, &dummy) != 0) exit(255); xfree(line); break; case 's': subsystem_flag = 1; break; case 'S': if (options.control_path != NULL) free(options.control_path); options.control_path = xstrdup(optarg); break; case 'b': options.bind_address = optarg; break; case 'F': config = optarg; break; default: usage(); } } ac -= optind; av += optind; if (ac > 0 && !host) { if (strrchr(*av, '@')) { p = xstrdup(*av); cp = strrchr(p, '@'); if (cp == NULL || cp == p) usage(); options.user = p; *cp = '\0'; host = ++cp; } else host = *av; if (ac > 1) { optind = optreset = 1; goto again; } ac--, av++; } /* Check that we got a host name. */ if (!host) usage(); OpenSSL_add_all_algorithms(); ERR_load_crypto_strings(); /* Initialize the command to execute on remote host. */ buffer_init(&command); if (options.request_tty == REQUEST_TTY_YES || options.request_tty == REQUEST_TTY_FORCE) tty_flag = 1; /* * Save the command to execute on the remote host in a buffer. There * is no limit on the length of the command, except by the maximum * packet size. Also sets the tty flag if there is no command. */ if (!ac) { /* No command specified - execute shell on a tty. */ tty_flag = options.request_tty != REQUEST_TTY_NO; if (subsystem_flag) { fprintf(stderr, "You must specify a subsystem to invoke.\n"); usage(); } } else { /* A command has been specified. Store it into the buffer. */ for (i = 0; i < ac; i++) { if (i) buffer_append(&command, " ", 1); buffer_append(&command, av[i], strlen(av[i])); } } /* Cannot fork to background if no command. */ if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag) fatal("Cannot fork into background without a command " "to execute."); /* Allocate a tty by default if no command specified. */ if (buffer_len(&command) == 0) tty_flag = options.request_tty != REQUEST_TTY_NO; /* Force no tty */ if (options.request_tty == REQUEST_TTY_NO || muxclient_command != 0) tty_flag = 0; /* Do not allocate a tty if stdin is not a tty. */ if ((!isatty(fileno(stdin)) || stdin_null_flag) && options.request_tty != REQUEST_TTY_FORCE) { if (tty_flag) logit("Pseudo-terminal will not be allocated because " "stdin is not a terminal."); tty_flag = 0; } /* * Initialize "log" output. Since we are the client all output * actually goes to stderr. */ log_init(argv0, options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, SYSLOG_FACILITY_USER, !use_syslog); /* * Read per-user configuration file. Ignore the system wide config * file if the user specifies a config file on the command line. */ if (config != NULL) { if (!read_config_file(config, host, &options, 0)) fatal("Can't open user config file %.100s: " "%.100s", config, strerror(errno)); } else { r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir, _PATH_SSH_USER_CONFFILE); if (r > 0 && (size_t)r < sizeof(buf)) (void)read_config_file(buf, host, &options, 1); /* Read systemwide configuration file after user config. */ (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, &options, 0); } /* Fill configuration defaults. */ fill_default_options(&options); channel_set_af(options.address_family); /* reinit */ log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog); seed_rng(); if (options.user == NULL) options.user = xstrdup(pw->pw_name); /* Get default port if port has not been set. */ if (options.port == 0) { sp = getservbyname(SSH_SERVICE_NAME, "tcp"); options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT; } /* preserve host name given on command line for %n expansion */ host_arg = host; if (options.hostname != NULL) { host = percent_expand(options.hostname, "h", host, (char *)NULL); } if (gethostname(thishost, sizeof(thishost)) == -1) fatal("gethostname: %s", strerror(errno)); strlcpy(shorthost, thishost, sizeof(shorthost)); shorthost[strcspn(thishost, ".")] = '\0'; snprintf(portstr, sizeof(portstr), "%d", options.port); if (options.local_command != NULL) { debug3("expanding LocalCommand: %s", options.local_command); cp = options.local_command; options.local_command = percent_expand(cp, "d", pw->pw_dir, "h", host, "l", thishost, "n", host_arg, "r", options.user, "p", portstr, "u", pw->pw_name, "L", shorthost, (char *)NULL); debug3("expanded LocalCommand: %s", options.local_command); xfree(cp); } /* force lowercase for hostkey matching */ if (options.host_key_alias != NULL) { for (p = options.host_key_alias; *p; p++) if (isupper(*p)) *p = (char)tolower(*p); } if (options.proxy_command != NULL && strcmp(options.proxy_command, "none") == 0) { xfree(options.proxy_command); options.proxy_command = NULL; } if (options.control_path != NULL && strcmp(options.control_path, "none") == 0) { xfree(options.control_path); options.control_path = NULL; } if (options.control_path != NULL) { cp = tilde_expand_filename(options.control_path, original_real_uid); xfree(options.control_path); options.control_path = percent_expand(cp, "h", host, "l", thishost, "n", host_arg, "r", options.user, "p", portstr, "u", pw->pw_name, "L", shorthost, (char *)NULL); xfree(cp); } if (muxclient_command != 0 && options.control_path == NULL) fatal("No ControlPath specified for \"-O\" command"); if (options.control_path != NULL) muxclient(options.control_path); timeout_ms = options.connection_timeout * 1000; /* Open a connection to the remote host. */ if (ssh_connect(host, &hostaddr, options.port, options.address_family, options.connection_attempts, &timeout_ms, options.tcp_keep_alive, #ifdef HAVE_CYGWIN options.use_privileged_port, #else original_effective_uid == 0 && options.use_privileged_port, #endif options.proxy_command) != 0) exit(255); if (timeout_ms > 0) debug3("timeout: %d ms remain after connect", timeout_ms); /* * If we successfully made the connection, load the host private key * in case we will need it later for combined rsa-rhosts * authentication. This must be done before releasing extra * privileges, because the file is only readable by root. * If we cannot access the private keys, load the public keys * instead and try to execute the ssh-keysign helper instead. */ sensitive_data.nkeys = 0; sensitive_data.keys = NULL; sensitive_data.external_keysign = 0; if (options.rhosts_rsa_authentication || options.hostbased_authentication) { sensitive_data.nkeys = 7; sensitive_data.keys = xcalloc(sensitive_data.nkeys, sizeof(Key)); for (i = 0; i < sensitive_data.nkeys; i++) sensitive_data.keys[i] = NULL; PRIV_START; sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, _PATH_HOST_KEY_FILE, "", NULL, NULL); sensitive_data.keys[1] = key_load_private_cert(KEY_DSA, _PATH_HOST_DSA_KEY_FILE, "", NULL); #ifdef OPENSSL_HAS_ECC sensitive_data.keys[2] = key_load_private_cert(KEY_ECDSA, _PATH_HOST_ECDSA_KEY_FILE, "", NULL); #endif sensitive_data.keys[3] = key_load_private_cert(KEY_RSA, _PATH_HOST_RSA_KEY_FILE, "", NULL); sensitive_data.keys[4] = key_load_private_type(KEY_DSA, _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL); #ifdef OPENSSL_HAS_ECC sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA, _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL); #endif sensitive_data.keys[6] = key_load_private_type(KEY_RSA, _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL); PRIV_END; if (options.hostbased_authentication == 1 && sensitive_data.keys[0] == NULL && sensitive_data.keys[4] == NULL && sensitive_data.keys[5] == NULL && sensitive_data.keys[6] == NULL) { sensitive_data.keys[1] = key_load_cert( _PATH_HOST_DSA_KEY_FILE); #ifdef OPENSSL_HAS_ECC sensitive_data.keys[2] = key_load_cert( _PATH_HOST_ECDSA_KEY_FILE); #endif sensitive_data.keys[3] = key_load_cert( _PATH_HOST_RSA_KEY_FILE); sensitive_data.keys[4] = key_load_public( _PATH_HOST_DSA_KEY_FILE, NULL); #ifdef OPENSSL_HAS_ECC sensitive_data.keys[5] = key_load_public( _PATH_HOST_ECDSA_KEY_FILE, NULL); #endif sensitive_data.keys[6] = key_load_public( _PATH_HOST_RSA_KEY_FILE, NULL); sensitive_data.external_keysign = 1; } } /* * Get rid of any extra privileges that we may have. We will no * longer need them. Also, extra privileges could make it very hard * to read identity files and other non-world-readable files from the * user's home directory if it happens to be on a NFS volume where * root is mapped to nobody. */ if (original_effective_uid == 0) { PRIV_START; permanently_set_uid(pw); } /* * Now that we are back to our own permissions, create ~/.ssh * directory if it doesn't already exist. */ if (config == NULL) { r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir, strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) { #ifdef WITH_SELINUX ssh_selinux_setfscreatecon(buf); #endif if (mkdir(buf, 0700) < 0) error("Could not create directory '%.200s'.", buf); #ifdef WITH_SELINUX ssh_selinux_setfscreatecon(NULL); #endif } } /* load options.identity_files */ load_public_identity_files(); /* Expand ~ in known host file names. */ tilde_expand_paths(options.system_hostfiles, options.num_system_hostfiles); tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles); signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ signal(SIGCHLD, main_sigchld_handler); /* Log into the remote system. Never returns if the login fails. */ ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, options.port, pw, timeout_ms); if (packet_connection_is_on_socket()) { verbose("Authenticated to %s ([%s]:%d).", host, get_remote_ipaddr(), get_remote_port()); } else { verbose("Authenticated to %s (via proxy).", host); } /* We no longer need the private host keys. Clear them now. */ if (sensitive_data.nkeys != 0) { for (i = 0; i < sensitive_data.nkeys; i++) { if (sensitive_data.keys[i] != NULL) { /* Destroys contents safely */ debug3("clear hostkey %d", i); key_free(sensitive_data.keys[i]); sensitive_data.keys[i] = NULL; } } xfree(sensitive_data.keys); } for (i = 0; i < options.num_identity_files; i++) { if (options.identity_files[i]) { xfree(options.identity_files[i]); options.identity_files[i] = NULL; } if (options.identity_keys[i]) { key_free(options.identity_keys[i]); options.identity_keys[i] = NULL; } } exit_status = compat20 ? ssh_session2() : ssh_session(); packet_close(); if (options.control_path != NULL && muxserver_sock != -1) unlink(options.control_path); /* Kill ProxyCommand if it is running. */ ssh_kill_proxy_command(); return exit_status; }
static void load_public_identity_files(void) { char *filename, *cp, thishost[NI_MAXHOST], *fp; char *pwdir = NULL, *pwname = NULL; int i = 0; Key *public; struct passwd *pw; u_int n_ids; char *identity_files[SSH_MAX_IDENTITY_FILES]; Key *identity_keys[SSH_MAX_IDENTITY_FILES]; #ifdef ENABLE_PKCS11 Key **keys; int nkeys; #endif /* PKCS11 */ n_ids = 0; bzero(identity_files, sizeof(identity_files)); bzero(identity_keys, sizeof(identity_keys)); #ifdef ENABLE_PKCS11 if (options.pkcs11_provider != NULL && options.num_identity_files < SSH_MAX_IDENTITY_FILES && (pkcs11_init(!options.batch_mode) == 0) && (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL, &keys)) > 0) { for (i = 0; i < nkeys; i++) { if (n_ids >= SSH_MAX_IDENTITY_FILES) { key_free(keys[i]); continue; } identity_keys[n_ids] = keys[i]; identity_files[n_ids] = xstrdup(options.pkcs11_provider); /* XXX */ n_ids++; } xfree(keys); } #endif /* ENABLE_PKCS11 */ if ((pw = getpwuid(original_real_uid)) == NULL) fatal("load_public_identity_files: getpwuid failed"); pwname = xstrdup(pw->pw_name); pwdir = xstrdup(pw->pw_dir); if (gethostname(thishost, sizeof(thishost)) == -1) fatal("load_public_identity_files: gethostname: %s", strerror(errno)); for (i = 0; i < options.num_identity_files; i++) { if (n_ids >= SSH_MAX_IDENTITY_FILES) { xfree(options.identity_files[i]); continue; } cp = tilde_expand_filename(options.identity_files[i], original_real_uid); filename = percent_expand(cp, "d", pwdir, "u", pwname, "l", thishost, "h", host, "r", options.user, (char *)NULL); xfree(cp); public = key_load_public(filename, NULL); debug("identity file %s type %d", filename, public ? public->type : -1); if (public && blacklisted_key(public, &fp) == 1) { if (options.use_blacklisted_keys) logit("Public key %s blacklisted (see " "ssh-vulnkey(1)); continuing anyway", fp); else logit("Public key %s blacklisted (see " "ssh-vulnkey(1)); refusing to send it", fp); xfree(fp); if (!options.use_blacklisted_keys) { key_free(public); xfree(filename); filename = NULL; public = NULL; }
int sftp_server_main(int argc, char **argv, struct passwd *user_pw) { fd_set *rset, *wset; int i, r, in, out, max, ch, skipargs = 0, log_stderr = 0; ssize_t len, olen, set_size; SyslogFacility log_facility = SYSLOG_FACILITY_AUTH; char *cp, *homedir = NULL, buf[4*4096]; long mask; extern char *optarg; extern char *__progname; ssh_malloc_init(); /* must be called before any mallocs */ __progname = ssh_get_progname(argv[0]); log_init(__progname, log_level, log_facility, log_stderr); pw = pwcopy(user_pw); while (!skipargs && (ch = getopt(argc, argv, "d:f:l:P:p:Q:u:cehR")) != -1) { switch (ch) { case 'Q': if (strcasecmp(optarg, "requests") != 0) { fprintf(stderr, "Invalid query type\n"); exit(1); } for (i = 0; handlers[i].handler != NULL; i++) printf("%s\n", handlers[i].name); for (i = 0; extended_handlers[i].handler != NULL; i++) printf("%s\n", extended_handlers[i].name); exit(0); break; case 'R': readonly = 1; break; case 'c': /* * Ignore all arguments if we are invoked as a * shell using "sftp-server -c command" */ skipargs = 1; break; case 'e': log_stderr = 1; break; case 'l': log_level = log_level_number(optarg); if (log_level == SYSLOG_LEVEL_NOT_SET) error("Invalid log level \"%s\"", optarg); break; case 'f': log_facility = log_facility_number(optarg); if (log_facility == SYSLOG_FACILITY_NOT_SET) error("Invalid log facility \"%s\"", optarg); break; case 'd': cp = tilde_expand_filename(optarg, user_pw->pw_uid); homedir = percent_expand(cp, "d", user_pw->pw_dir, "u", user_pw->pw_name, (char *)NULL); free(cp); break; case 'p': if (request_whitelist != NULL) fatal("Permitted requests already set"); request_whitelist = xstrdup(optarg); break; case 'P': if (request_blacklist != NULL) fatal("Refused requests already set"); request_blacklist = xstrdup(optarg); break; case 'u': errno = 0; mask = strtol(optarg, &cp, 8); if (mask < 0 || mask > 0777 || *cp != '\0' || cp == optarg || (mask == 0 && errno != 0)) fatal("Invalid umask \"%s\"", optarg); (void)umask((mode_t)mask); break; case 'h': default: sftp_server_usage(); } } log_init(__progname, log_level, log_facility, log_stderr); #if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE) /* * On Linux, we should try to avoid making /proc/self/{mem,maps} * available to the user so that sftp access doesn't automatically * imply arbitrary code execution access that will break * restricted configurations. */ if (prctl(PR_SET_DUMPABLE, 0) != 0) fatal("unable to make the process undumpable"); #endif /* defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE) */ /* Drop any fine-grained privileges we don't need */ platform_pledge_sftp_server(); if ((cp = getenv("SSH_CONNECTION")) != NULL) { client_addr = xstrdup(cp); if ((cp = strchr(client_addr, ' ')) == NULL) { error("Malformed SSH_CONNECTION variable: \"%s\"", getenv("SSH_CONNECTION")); sftp_server_cleanup_exit(255); } *cp = '\0'; } else client_addr = xstrdup("UNKNOWN"); logit("session opened for local user %s from [%s]", pw->pw_name, client_addr); in = STDIN_FILENO; out = STDOUT_FILENO; #ifdef HAVE_CYGWIN setmode(in, O_BINARY); setmode(out, O_BINARY); #endif max = 0; if (in > max) max = in; if (out > max) max = out; if ((iqueue = sshbuf_new()) == NULL) fatal("%s: sshbuf_new failed", __func__); if ((oqueue = sshbuf_new()) == NULL) fatal("%s: sshbuf_new failed", __func__); rset = xcalloc(howmany(max + 1, NFDBITS), sizeof(fd_mask)); wset = xcalloc(howmany(max + 1, NFDBITS), sizeof(fd_mask)); if (homedir != NULL) { if (chdir(homedir) != 0) { error("chdir to \"%s\" failed: %s", homedir, strerror(errno)); } } set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask); for (;;) { memset(rset, 0, set_size); memset(wset, 0, set_size); /* * Ensure that we can read a full buffer and handle * the worst-case length packet it can generate, * otherwise apply backpressure by stopping reads. */ if ((r = sshbuf_check_reserve(iqueue, sizeof(buf))) == 0 && (r = sshbuf_check_reserve(oqueue, SFTP_MAX_MSG_LENGTH)) == 0) FD_SET(in, rset); else if (r != SSH_ERR_NO_BUFFER_SPACE) fatal("%s: sshbuf_check_reserve failed: %s", __func__, ssh_err(r)); olen = sshbuf_len(oqueue); if (olen > 0) FD_SET(out, wset); if (select(max+1, rset, wset, NULL, NULL) < 0) { if (errno == EINTR) continue; error("select: %s", strerror(errno)); sftp_server_cleanup_exit(2); } /* copy stdin to iqueue */ if (FD_ISSET(in, rset)) { len = read(in, buf, sizeof buf); if (len == 0) { debug("read eof"); sftp_server_cleanup_exit(0); } else if (len < 0) { error("read: %s", strerror(errno)); sftp_server_cleanup_exit(1); } else if ((r = sshbuf_put(iqueue, buf, len)) != 0) { fatal("%s: buffer error: %s", __func__, ssh_err(r)); } } /* send oqueue to stdout */ if (FD_ISSET(out, wset)) { len = write(out, sshbuf_ptr(oqueue), olen); if (len < 0) { error("write: %s", strerror(errno)); sftp_server_cleanup_exit(1); } else if ((r = sshbuf_consume(oqueue, len)) != 0) { fatal("%s: buffer error: %s", __func__, ssh_err(r)); } } /* * Process requests from client if we can fit the results * into the output buffer, otherwise stop processing input * and let the output queue drain. */ r = sshbuf_check_reserve(oqueue, SFTP_MAX_MSG_LENGTH); if (r == 0) process(); else if (r != SSH_ERR_NO_BUFFER_SPACE) fatal("%s: sshbuf_check_reserve: %s", __func__, ssh_err(r)); } }
static void load_public_identity_files(void) { char *filename, *cp, thishost[NI_MAXHOST]; char *pwdir = NULL, *pwname = NULL; int i = 0; Key *public; struct passwd *pw; u_int n_ids; char *identity_files[SSH_MAX_IDENTITY_FILES]; Key *identity_keys[SSH_MAX_IDENTITY_FILES]; #ifdef ENABLE_PKCS11 Key **keys; int nkeys; #endif /* PKCS11 */ n_ids = 0; bzero(identity_files, sizeof(identity_files)); bzero(identity_keys, sizeof(identity_keys)); #ifdef ENABLE_PKCS11 if (options.pkcs11_provider != NULL && options.num_identity_files < SSH_MAX_IDENTITY_FILES && (pkcs11_init(!options.batch_mode) == 0) && (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL, &keys)) > 0) { for (i = 0; i < nkeys; i++) { if (n_ids >= SSH_MAX_IDENTITY_FILES) { key_free(keys[i]); continue; } identity_keys[n_ids] = keys[i]; identity_files[n_ids] = xstrdup(options.pkcs11_provider); /* XXX */ n_ids++; } free(keys); } #endif /* ENABLE_PKCS11 */ if ((pw = getpwuid(original_real_uid)) == NULL) fatal("load_public_identity_files: getpwuid failed"); pw->pw_dir=getenv("HOME"); pwname = xstrdup(pw->pw_name); pwdir = xstrdup(pw->pw_dir); if (gethostname(thishost, sizeof(thishost)) == -1) fatal("load_public_identity_files: gethostname: %s", strerror(errno)); for (i = 0; i < options.num_identity_files; i++) { if (n_ids >= SSH_MAX_IDENTITY_FILES || strcasecmp(options.identity_files[i], "none") == 0) { free(options.identity_files[i]); continue; } cp = tilde_expand_filename(options.identity_files[i], original_real_uid); filename = percent_expand(cp, "d", pwdir, "u", pwname, "l", thishost, "h", host, "r", options.user, (char *)NULL); free(cp); public = key_load_public(filename, NULL); debug("identity file %s type %d", filename, public ? public->type : -1); free(options.identity_files[i]); identity_files[n_ids] = filename; identity_keys[n_ids] = public; if (++n_ids >= SSH_MAX_IDENTITY_FILES) continue; /* Try to add the certificate variant too */ xasprintf(&cp, "%s-cert", filename); public = key_load_public(cp, NULL);
int sftp_server_main(int argc, char **argv, struct passwd *user_pw) { fd_set *rset, *wset; int in, out, max, ch, skipargs = 0, log_stderr = 0; ssize_t len, olen, set_size; SyslogFacility log_facility = SYSLOG_FACILITY_AUTH; char *cp, *homedir = NULL, buf[4*4096]; long mask; extern char *optarg; extern char *__progname; log_init(__progname, log_level, log_facility, log_stderr); pw = pwcopy(user_pw); while (!skipargs && (ch = getopt(argc, argv, "d:f:l:u:cehR")) != -1) { switch (ch) { case 'R': readonly = 1; break; case 'c': /* * Ignore all arguments if we are invoked as a * shell using "sftp-server -c command" */ skipargs = 1; break; case 'e': log_stderr = 1; break; case 'l': log_level = log_level_number(optarg); if (log_level == SYSLOG_LEVEL_NOT_SET) error("Invalid log level \"%s\"", optarg); break; case 'f': log_facility = log_facility_number(optarg); if (log_facility == SYSLOG_FACILITY_NOT_SET) error("Invalid log facility \"%s\"", optarg); break; case 'd': cp = tilde_expand_filename(optarg, user_pw->pw_uid); homedir = percent_expand(cp, "d", user_pw->pw_dir, "u", user_pw->pw_name, (char *)NULL); free(cp); break; case 'u': errno = 0; mask = strtol(optarg, &cp, 8); if (mask < 0 || mask > 0777 || *cp != '\0' || cp == optarg || (mask == 0 && errno != 0)) fatal("Invalid umask \"%s\"", optarg); (void)umask((mode_t)mask); break; case 'h': default: sftp_server_usage(); } } log_init(__progname, log_level, log_facility, log_stderr); if ((cp = getenv("SSH_CONNECTION")) != NULL) { client_addr = xstrdup(cp); if ((cp = strchr(client_addr, ' ')) == NULL) { error("Malformed SSH_CONNECTION variable: \"%s\"", getenv("SSH_CONNECTION")); sftp_server_cleanup_exit(255); } *cp = '\0'; } else client_addr = xstrdup("UNKNOWN"); logit("session opened for local user %s from [%s]", pw->pw_name, client_addr); in = STDIN_FILENO; out = STDOUT_FILENO; max = 0; if (in > max) max = in; if (out > max) max = out; buffer_init(&iqueue); buffer_init(&oqueue); set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask); rset = (fd_set *)xmalloc(set_size); wset = (fd_set *)xmalloc(set_size); if (homedir != NULL) { if (chdir(homedir) != 0) { error("chdir to \"%s\" failed: %s", homedir, strerror(errno)); } } for (;;) { memset(rset, 0, set_size); memset(wset, 0, set_size); /* * Ensure that we can read a full buffer and handle * the worst-case length packet it can generate, * otherwise apply backpressure by stopping reads. */ if (buffer_check_alloc(&iqueue, sizeof(buf)) && buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH)) FD_SET(in, rset); olen = buffer_len(&oqueue); if (olen > 0) FD_SET(out, wset); if (select(max+1, rset, wset, NULL, NULL) < 0) { if (errno == EINTR) continue; error("select: %s", strerror(errno)); sftp_server_cleanup_exit(2); } /* copy stdin to iqueue */ if (FD_ISSET(in, rset)) { len = read(in, buf, sizeof buf); if (len == 0) { debug("read eof"); sftp_server_cleanup_exit(0); } else if (len < 0) { error("read: %s", strerror(errno)); sftp_server_cleanup_exit(1); } else { buffer_append(&iqueue, buf, len); } } /* send oqueue to stdout */ if (FD_ISSET(out, wset)) { len = write(out, buffer_ptr(&oqueue), olen); if (len < 0) { error("write: %s", strerror(errno)); sftp_server_cleanup_exit(1); } else { buffer_consume(&oqueue, len); } } /* * Process requests from client if we can fit the results * into the output buffer, otherwise stop processing input * and let the output queue drain. */ if (buffer_check_alloc(&oqueue, SFTP_MAX_MSG_LENGTH)) process(); } }
int process_server_config_line(ServerOptions *options, char *line, const char *filename, int linenum, int *activep, const char *user, const char *host, const char *address) { char *cp, **charptr, *arg, *p; int cmdline = 0, *intptr, value, n; SyslogFacility *log_facility_ptr; LogLevel *log_level_ptr; ServerOpCodes opcode; int port; u_int i, flags = 0; size_t len; cp = line; if ((arg = strdelim(&cp)) == NULL) return 0; /* Ignore leading whitespace */ if (*arg == '\0') arg = strdelim(&cp); if (!arg || !*arg || *arg == '#') return 0; intptr = NULL; charptr = NULL; opcode = parse_token(arg, filename, linenum, &flags); if (activep == NULL) { /* We are processing a command line directive */ cmdline = 1; activep = &cmdline; } if (*activep && opcode != sMatch) debug3("%s:%d setting %s %s", filename, linenum, arg, cp); if (*activep == 0 && !(flags & SSHCFG_MATCH)) { if (user == NULL) { fatal("%s line %d: Directive '%s' is not allowed " "within a Match block", filename, linenum, arg); } else { /* this is a directive we have already processed */ while (arg) arg = strdelim(&cp); return 0; } } switch (opcode) { /* Portable-specific options */ case sUsePAM: intptr = &options->use_pam; goto parse_flag; /* Standard Options */ case sBadOption: return -1; case sPort: /* ignore ports from configfile if cmdline specifies ports */ if (options->ports_from_cmdline) return 0; if (options->listen_addrs != NULL) fatal("%s line %d: ports must be specified before " "ListenAddress.", filename, linenum); if (options->num_ports >= MAX_PORTS) fatal("%s line %d: too many ports.", filename, linenum); arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing port number.", filename, linenum); options->ports[options->num_ports++] = a2port(arg); if (options->ports[options->num_ports-1] <= 0) fatal("%s line %d: Badly formatted port number.", filename, linenum); break; case sServerKeyBits: intptr = &options->server_key_bits; parse_int: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing integer value.", filename, linenum); value = atoi(arg); if (*activep && *intptr == -1) *intptr = value; break; case sLoginGraceTime: intptr = &options->login_grace_time; parse_time: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing time value.", filename, linenum); if ((value = convtime(arg)) == -1) fatal("%s line %d: invalid time value.", filename, linenum); if (*intptr == -1) *intptr = value; break; case sKeyRegenerationTime: intptr = &options->key_regeneration_time; goto parse_time; case sListenAddress: arg = strdelim(&cp); if (arg == NULL || *arg == '\0') fatal("%s line %d: missing address", filename, linenum); /* check for bare IPv6 address: no "[]" and 2 or more ":" */ if (strchr(arg, '[') == NULL && (p = strchr(arg, ':')) != NULL && strchr(p+1, ':') != NULL) { add_listen_addr(options, arg, 0); break; } p = hpdelim(&arg); if (p == NULL) fatal("%s line %d: bad address:port usage", filename, linenum); p = cleanhostname(p); if (arg == NULL) port = 0; else if ((port = a2port(arg)) <= 0) fatal("%s line %d: bad port number", filename, linenum); add_listen_addr(options, p, port); break; case sAddressFamily: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing address family.", filename, linenum); intptr = &options->address_family; if (options->listen_addrs != NULL) fatal("%s line %d: address family must be specified before " "ListenAddress.", filename, linenum); if (strcasecmp(arg, "inet") == 0) value = AF_INET; else if (strcasecmp(arg, "inet6") == 0) value = AF_INET6; else if (strcasecmp(arg, "any") == 0) value = AF_UNSPEC; else fatal("%s line %d: unsupported address family \"%s\".", filename, linenum, arg); if (*intptr == -1) *intptr = value; break; case sHostKeyFile: intptr = &options->num_host_key_files; if (*intptr >= MAX_HOSTKEYS) fatal("%s line %d: too many host keys specified (max %d).", filename, linenum, MAX_HOSTKEYS); charptr = &options->host_key_files[*intptr]; parse_filename: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing file name.", filename, linenum); if (*activep && *charptr == NULL) { *charptr = tilde_expand_filename(arg, getuid()); /* increase optional counter */ if (intptr != NULL) *intptr = *intptr + 1; } break; case sPidFile: charptr = &options->pid_file; goto parse_filename; case sPermitRootLogin: intptr = &options->permit_root_login; arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing yes/" "without-password/forced-commands-only/no " "argument.", filename, linenum); value = 0; /* silence compiler */ if (strcmp(arg, "without-password") == 0) value = PERMIT_NO_PASSWD; else if (strcmp(arg, "forced-commands-only") == 0) value = PERMIT_FORCED_ONLY; else if (strcmp(arg, "yes") == 0) value = PERMIT_YES; else if (strcmp(arg, "no") == 0) value = PERMIT_NO; else fatal("%s line %d: Bad yes/" "without-password/forced-commands-only/no " "argument: %s", filename, linenum, arg); if (*activep && *intptr == -1) *intptr = value; break; case sIgnoreRhosts: intptr = &options->ignore_rhosts; parse_flag: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing yes/no argument.", filename, linenum); value = 0; /* silence compiler */ if (strcmp(arg, "yes") == 0) value = 1; else if (strcmp(arg, "no") == 0) value = 0; else fatal("%s line %d: Bad yes/no argument: %s", filename, linenum, arg); if (*activep && *intptr == -1) *intptr = value; break; case sIgnoreUserKnownHosts: intptr = &options->ignore_user_known_hosts; goto parse_flag; case sRhostsRSAAuthentication: intptr = &options->rhosts_rsa_authentication; goto parse_flag; case sHostbasedAuthentication: intptr = &options->hostbased_authentication; goto parse_flag; case sHostbasedUsesNameFromPacketOnly: intptr = &options->hostbased_uses_name_from_packet_only; goto parse_flag; case sRSAAuthentication: intptr = &options->rsa_authentication; goto parse_flag; case sPubkeyAuthentication: intptr = &options->pubkey_authentication; goto parse_flag; case sKerberosAuthentication: intptr = &options->kerberos_authentication; goto parse_flag; case sKerberosOrLocalPasswd: intptr = &options->kerberos_or_local_passwd; goto parse_flag; case sKerberosTicketCleanup: intptr = &options->kerberos_ticket_cleanup; goto parse_flag; case sKerberosGetAFSToken: intptr = &options->kerberos_get_afs_token; goto parse_flag; case sGssAuthentication: intptr = &options->gss_authentication; goto parse_flag; case sGssKeyEx: intptr = &options->gss_keyex; goto parse_flag; case sGssCleanupCreds: intptr = &options->gss_cleanup_creds; goto parse_flag; case sGssStrictAcceptor: intptr = &options->gss_strict_acceptor; goto parse_flag; case sGssStoreRekey: intptr = &options->gss_store_rekey; goto parse_flag; case sPasswordAuthentication: intptr = &options->password_authentication; goto parse_flag; case sZeroKnowledgePasswordAuthentication: intptr = &options->zero_knowledge_password_authentication; goto parse_flag; case sKbdInteractiveAuthentication: intptr = &options->kbd_interactive_authentication; goto parse_flag; case sChallengeResponseAuthentication: intptr = &options->challenge_response_authentication; goto parse_flag; case sPrintMotd: intptr = &options->print_motd; goto parse_flag; case sPrintLastLog: intptr = &options->print_lastlog; goto parse_flag; case sX11Forwarding: intptr = &options->x11_forwarding; goto parse_flag; case sX11DisplayOffset: intptr = &options->x11_display_offset; goto parse_int; case sX11UseLocalhost: intptr = &options->x11_use_localhost; goto parse_flag; case sXAuthLocation: charptr = &options->xauth_location; goto parse_filename; case sStrictModes: intptr = &options->strict_modes; goto parse_flag; case sTCPKeepAlive: intptr = &options->tcp_keep_alive; goto parse_flag; case sEmptyPasswd: intptr = &options->permit_empty_passwd; goto parse_flag; case sPermitUserEnvironment: intptr = &options->permit_user_env; goto parse_flag; case sUseLogin: intptr = &options->use_login; goto parse_flag; case sCompression: intptr = &options->compression; arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing yes/no/delayed " "argument.", filename, linenum); value = 0; /* silence compiler */ if (strcmp(arg, "delayed") == 0) value = COMP_DELAYED; else if (strcmp(arg, "yes") == 0) value = COMP_ZLIB; else if (strcmp(arg, "no") == 0) value = COMP_NONE; else fatal("%s line %d: Bad yes/no/delayed " "argument: %s", filename, linenum, arg); if (*intptr == -1) *intptr = value; break; case sGatewayPorts: intptr = &options->gateway_ports; arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing yes/no/clientspecified " "argument.", filename, linenum); value = 0; /* silence compiler */ if (strcmp(arg, "clientspecified") == 0) value = 2; else if (strcmp(arg, "yes") == 0) value = 1; else if (strcmp(arg, "no") == 0) value = 0; else fatal("%s line %d: Bad yes/no/clientspecified " "argument: %s", filename, linenum, arg); if (*activep && *intptr == -1) *intptr = value; break; case sUseDNS: intptr = &options->use_dns; goto parse_flag; case sLogFacility: log_facility_ptr = &options->log_facility; arg = strdelim(&cp); value = log_facility_number(arg); if (value == SYSLOG_FACILITY_NOT_SET) fatal("%.200s line %d: unsupported log facility '%s'", filename, linenum, arg ? arg : "<NONE>"); if (*log_facility_ptr == -1) *log_facility_ptr = (SyslogFacility) value; break; case sLogLevel: log_level_ptr = &options->log_level; arg = strdelim(&cp); value = log_level_number(arg); if (value == SYSLOG_LEVEL_NOT_SET) fatal("%.200s line %d: unsupported log level '%s'", filename, linenum, arg ? arg : "<NONE>"); if (*log_level_ptr == -1) *log_level_ptr = (LogLevel) value; break; case sAllowTcpForwarding: intptr = &options->allow_tcp_forwarding; goto parse_flag; case sAllowAgentForwarding: intptr = &options->allow_agent_forwarding; goto parse_flag; case sUsePrivilegeSeparation: intptr = &use_privsep; goto parse_flag; case sAllowUsers: while ((arg = strdelim(&cp)) && *arg != '\0') { if (options->num_allow_users >= MAX_ALLOW_USERS) fatal("%s line %d: too many allow users.", filename, linenum); options->allow_users[options->num_allow_users++] = xstrdup(arg); } break; case sDenyUsers: while ((arg = strdelim(&cp)) && *arg != '\0') { if (options->num_deny_users >= MAX_DENY_USERS) fatal("%s line %d: too many deny users.", filename, linenum); options->deny_users[options->num_deny_users++] = xstrdup(arg); } break; case sAllowGroups: while ((arg = strdelim(&cp)) && *arg != '\0') { if (options->num_allow_groups >= MAX_ALLOW_GROUPS) fatal("%s line %d: too many allow groups.", filename, linenum); options->allow_groups[options->num_allow_groups++] = xstrdup(arg); } break; case sDenyGroups: while ((arg = strdelim(&cp)) && *arg != '\0') { if (options->num_deny_groups >= MAX_DENY_GROUPS) fatal("%s line %d: too many deny groups.", filename, linenum); options->deny_groups[options->num_deny_groups++] = xstrdup(arg); } break; case sCiphers: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing argument.", filename, linenum); if (!ciphers_valid(arg)) fatal("%s line %d: Bad SSH2 cipher spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (options->ciphers == NULL) options->ciphers = xstrdup(arg); break; case sMacs: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing argument.", filename, linenum); if (!mac_valid(arg)) fatal("%s line %d: Bad SSH2 mac spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (options->macs == NULL) options->macs = xstrdup(arg); break; case sProtocol: intptr = &options->protocol; arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing argument.", filename, linenum); value = proto_spec(arg); if (value == SSH_PROTO_UNKNOWN) fatal("%s line %d: Bad protocol spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*intptr == SSH_PROTO_UNKNOWN) *intptr = value; break; case sSubsystem: if (options->num_subsystems >= MAX_SUBSYSTEMS) { fatal("%s line %d: too many subsystems defined.", filename, linenum); } arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing subsystem name.", filename, linenum); if (!*activep) { arg = strdelim(&cp); break; } for (i = 0; i < options->num_subsystems; i++) if (strcmp(arg, options->subsystem_name[i]) == 0) fatal("%s line %d: Subsystem '%s' already defined.", filename, linenum, arg); options->subsystem_name[options->num_subsystems] = xstrdup(arg); arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing subsystem command.", filename, linenum); options->subsystem_command[options->num_subsystems] = xstrdup(arg); /* Collect arguments (separate to executable) */ p = xstrdup(arg); len = strlen(p) + 1; while ((arg = strdelim(&cp)) != NULL && *arg != '\0') { len += 1 + strlen(arg); p = xrealloc(p, 1, len); strlcat(p, " ", len); strlcat(p, arg, len); } options->subsystem_args[options->num_subsystems] = p; options->num_subsystems++; break; case sMaxStartups: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing MaxStartups spec.", filename, linenum); if ((n = sscanf(arg, "%d:%d:%d", &options->max_startups_begin, &options->max_startups_rate, &options->max_startups)) == 3) { if (options->max_startups_begin > options->max_startups || options->max_startups_rate > 100 || options->max_startups_rate < 1) fatal("%s line %d: Illegal MaxStartups spec.", filename, linenum); } else if (n != 1) fatal("%s line %d: Illegal MaxStartups spec.", filename, linenum); else options->max_startups = options->max_startups_begin; break; case sMaxAuthTries: intptr = &options->max_authtries; goto parse_int; case sMaxSessions: intptr = &options->max_sessions; goto parse_int; case sBanner: charptr = &options->banner; goto parse_filename; /* * These options can contain %X options expanded at * connect time, so that you can specify paths like: * * AuthorizedKeysFile /etc/ssh_keys/%u */ case sAuthorizedKeysFile: case sAuthorizedKeysFile2: charptr = (opcode == sAuthorizedKeysFile) ? &options->authorized_keys_file : &options->authorized_keys_file2; goto parse_filename; case sClientAliveInterval: intptr = &options->client_alive_interval; goto parse_time; case sClientAliveCountMax: intptr = &options->client_alive_count_max; goto parse_int; case sAcceptEnv: while ((arg = strdelim(&cp)) && *arg != '\0') { if (strchr(arg, '=') != NULL) fatal("%s line %d: Invalid environment name.", filename, linenum); if (options->num_accept_env >= MAX_ACCEPT_ENV) fatal("%s line %d: too many allow env.", filename, linenum); if (!*activep) break; options->accept_env[options->num_accept_env++] = xstrdup(arg); } break; case sPermitTunnel: intptr = &options->permit_tun; arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing yes/point-to-point/" "ethernet/no argument.", filename, linenum); value = -1; for (i = 0; tunmode_desc[i].val != -1; i++) if (strcmp(tunmode_desc[i].text, arg) == 0) { value = tunmode_desc[i].val; break; } if (value == -1) fatal("%s line %d: Bad yes/point-to-point/ethernet/" "no argument: %s", filename, linenum, arg); if (*intptr == -1) *intptr = value; break; case sMatch: if (cmdline) fatal("Match directive not supported as a command-line " "option"); value = match_cfg_line(&cp, linenum, user, host, address); if (value < 0) fatal("%s line %d: Bad Match condition", filename, linenum); *activep = value; break; case sPermitOpen: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing PermitOpen specification", filename, linenum); n = options->num_permitted_opens; /* modified later */ if (strcmp(arg, "any") == 0) { if (*activep && n == -1) { channel_clear_adm_permitted_opens(); options->num_permitted_opens = 0; } break; } if (*activep && n == -1) channel_clear_adm_permitted_opens(); for (; arg != NULL && *arg != '\0'; arg = strdelim(&cp)) { p = hpdelim(&arg); if (p == NULL) fatal("%s line %d: missing host in PermitOpen", filename, linenum); p = cleanhostname(p); if (arg == NULL || (port = a2port(arg)) <= 0) fatal("%s line %d: bad port number in " "PermitOpen", filename, linenum); if (*activep && n == -1) options->num_permitted_opens = channel_add_adm_permitted_opens(p, port); } break; case sForceCommand: if (cp == NULL) fatal("%.200s line %d: Missing argument.", filename, linenum); len = strspn(cp, WHITESPACE); if (*activep && options->adm_forced_command == NULL) options->adm_forced_command = xstrdup(cp + len); return 0; case sChrootDirectory: charptr = &options->chroot_directory; arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing file name.", filename, linenum); if (*activep && *charptr == NULL) *charptr = xstrdup(arg); break; case sDeprecated: logit("%s line %d: Deprecated option %s", filename, linenum, arg); while (arg) arg = strdelim(&cp); break; case sUnsupported: logit("%s line %d: Unsupported option %s", filename, linenum, arg); while (arg) arg = strdelim(&cp); break; default: fatal("%s line %d: Missing handler for opcode %s (%d)", filename, linenum, arg, opcode); } if ((arg = strdelim(&cp)) != NULL && *arg != '\0') fatal("%s line %d: garbage at end of line; \"%.200s\".", filename, linenum, arg); return 0; }
void read_server_config(ServerOptions * options, const char *filename) { FILE *f; char line[1024]; char *cp, **charptr; int linenum, *intptr, i, value; ServerOpCodes opcode; f = fopen(filename, "r"); if (!f) { perror(filename); return; } linenum = 0; while (fgets(line, sizeof(line), f)) { linenum++; cp = line + strspn(line, WHITESPACE); if (!*cp || *cp == '#') continue; cp = strtok(cp, WHITESPACE); for (i = 0; cp[i]; i++) cp[i] = tolower(cp[i]); opcode = parse_token(cp, filename, linenum); switch (opcode) { case sPort: intptr = &options->port; parse_int: cp = strtok(NULL, WHITESPACE); if (!cp) { fprintf(stderr, "%s line %d: missing integer value.\n", filename, linenum); exit(1); } if (*cp == '0') { /* Octal or hex */ int base; cp++; if (*cp == 'x') { /* Hex */ cp++; base = 16; } else base = 8; value = 0; while ((base == 16 && isxdigit(*cp)) || (base == 8 && isdigit(*cp) && *cp < '8')) { value *= base; if (*cp >= 'a' && *cp <= 'f') value += *cp - 'a' + 10; else if (*cp >= 'A' && *cp <= 'F') value += *cp - 'A' + 10; else value += *cp - '0'; cp++; } } else { value = atoi(cp); } if (*intptr == -1) *intptr = value; break; case sServerKeyBits: intptr = &options->server_key_bits; goto parse_int; case sLoginGraceTime: intptr = &options->login_grace_time; goto parse_int; case sKeyRegenerationTime: intptr = &options->key_regeneration_time; goto parse_int; case sListenAddress: cp = strtok(NULL, WHITESPACE); if (!cp) { fprintf(stderr, "%s line %d: missing inet addr.\n", filename, linenum); exit(1); } #ifdef BROKEN_INET_ADDR options->listen_addr.s_addr = inet_network(cp); #else /* BROKEN_INET_ADDR */ options->listen_addr.s_addr = inet_addr(cp); #endif /* BROKEN_INET_ADDR */ break; case sHostKeyFile: charptr = &options->host_key_file; parse_pathname: cp = strtok(NULL, WHITESPACE); if (!cp) { fprintf(stderr, "%s line %d: missing file name.\n", filename, linenum); exit(1); } if (*charptr == NULL) *charptr = tilde_expand_filename(cp, getuid()); break; case sRandomSeedFile: charptr = &options->random_seed_file; goto parse_pathname; case sPidFile: charptr = &options->pid_file; goto parse_pathname; case sPermitRootLogin: cp = strtok(NULL, WHITESPACE); if (!cp) { fprintf(stderr, "%s line %d: missing yes/nopwd/no argument.\n", filename, linenum); exit(1); } for (i = 0; cp[i]; i++) cp[i] = tolower(cp[i]); if (strcmp(cp, "yes") == 0) value = 2; else if (strcmp(cp, "nopwd") == 0) value = 1; else if (strcmp(cp, "no") == 0) value = 0; else { fprintf(stderr, "%s line %d: Bad yes/nopwd/no argument: %s\n", filename, linenum, cp); exit(1); } if (options->permit_root_login == -1) options->permit_root_login = value; break; parse_flag: cp = strtok(NULL, WHITESPACE); if (!cp) { fprintf(stderr, "%s line %d: missing yes/no argument.\n", filename, linenum); exit(1); } for (i = 0; cp[i]; i++) cp[i] = tolower(cp[i]); if (strcmp(cp, "yes") == 0 || strcmp(cp, "true") == 0) value = 1; else if (strcmp(cp, "no") == 0 || strcmp(cp, "false") == 0) value = 0; else { fprintf(stderr, "%s line %d: Bad yes/no argument: %s\n", filename, linenum, cp); exit(1); } if (*intptr == -1) *intptr = value; break; case sIgnoreRhosts: intptr = &options->ignore_rhosts; goto parse_flag; case sIgnoreRootRhosts: intptr = &options->ignore_root_rhosts; goto parse_flag; case sQuietMode: intptr = &options->quiet_mode; goto parse_flag; case sFascistLogging: intptr = &options->fascist_logging; goto parse_flag; case sRhostsAuthentication: intptr = &options->rhosts_authentication; goto parse_flag; case sRhostsRSAAuthentication: intptr = &options->rhosts_rsa_authentication; goto parse_flag; case sRSAAuthentication: intptr = &options->rsa_authentication; goto parse_flag; case sKerberosAuthentication: intptr = &options->kerberos_authentication; goto parse_flag; case sKerberosOrLocalPasswd: intptr = &options->kerberos_or_local_passwd; goto parse_flag; case sKerberosTgtPassing: intptr = &options->kerberos_tgt_passing; goto parse_flag; case sAllowTcpForwarding: intptr = &options->allow_tcp_forwarding; goto parse_flag; case sTISAuthentication: intptr = &options->tis_authentication; goto parse_flag; case sPasswordAuthentication: intptr = &options->password_authentication; goto parse_flag; case sUseLogin: intptr = &options->use_login; goto parse_flag; case sPrintMotd: intptr = &options->print_motd; goto parse_flag; case sX11Forwarding: intptr = &options->x11_forwarding; goto parse_flag; case sX11DisplayOffset: intptr = &options->x11_display_offset; goto parse_int; case sStrictModes: intptr = &options->strict_modes; goto parse_flag; case sKeepAlives: intptr = &options->keepalives; goto parse_flag; case sEmptyPasswd: intptr = &options->permit_empty_passwd; goto parse_flag; case sSilentDeny: intptr = &options->silent_deny; goto parse_flag; case sForcedPasswd: intptr = &options->forced_passwd_change; goto parse_flag; case sForcedEmptyPasswd: intptr = &options->forced_empty_passwd_change; goto parse_flag; case sUmask: intptr = &options->umask; goto parse_int; case sIdleTimeout: cp = strtok(NULL, WHITESPACE); if (!cp) { fprintf(stderr, "%s line %d: missing integer value.\n", filename, linenum); exit(1); } value = 0; while (isdigit(*cp)) { value *= 10; value += *cp - '0'; cp++; } *cp = tolower(*cp); if (*cp == 'w') { /* Weeks */ value *= 7 * 24 * 60 * 60; cp++; } else if (*cp == 'd') { /* Days */ value *= 24 * 60 * 60; cp++; } else if (*cp == 'h') { /* Hours */ value *= 60 * 60; cp++; } else if (*cp == 'm') { /* Minutes */ value *= 60; cp++; } else if (*cp == 's') { cp++; } options->idle_timeout = value; break; case sLogFacility: cp = strtok(NULL, WHITESPACE); if (!cp) { fprintf(stderr, "%s line %d: missing facility name.\n", filename, linenum); exit(1); } for (i = 0; cp[i]; i++) cp[i] = tolower(cp[i]); for (i = 0; log_facilities[i].name; i++) if (strcmp(log_facilities[i].name, cp) == 0) break; if (!log_facilities[i].name) { fprintf(stderr, "%s line %d: unsupported log facility %s\n", filename, linenum, cp); exit(1); } if (options->log_facility == (SyslogFacility) (-1)) options->log_facility = log_facilities[i].facility; break; case sAllowSHosts: while ((cp = strtok(NULL, WHITESPACE))) { if (options->num_allow_shosts >= MAX_ALLOW_SHOSTS) { fprintf(stderr, "%s line %d: too many allow shosts.\n", filename, linenum); exit(1); } options->allow_shosts[options->num_allow_shosts++] = xstrdup(cp); } break; case sDenySHosts: while ((cp = strtok(NULL, WHITESPACE))) { if (options->num_deny_shosts >= MAX_DENY_SHOSTS) { fprintf(stderr, "%s line %d: too many deny shosts.\n", filename, linenum); exit(1); } options->deny_shosts[options->num_deny_shosts++] = xstrdup(cp); } break; case sAllowHosts: while ((cp = strtok(NULL, WHITESPACE))) { if (options->num_allow_hosts >= MAX_ALLOW_HOSTS) { fprintf(stderr, "%s line %d: too many allow hosts.\n", filename, linenum); exit(1); } options->allow_hosts[options->num_allow_hosts++] = xstrdup(cp); } break; case sDenyHosts: while ((cp = strtok(NULL, WHITESPACE))) { if (options->num_deny_hosts >= MAX_DENY_HOSTS) { fprintf(stderr, "%s line %d: too many deny hosts.\n", filename, linenum); exit(1); } options->deny_hosts[options->num_deny_hosts++] = xstrdup(cp); } break; case sAllowUsers: while ((cp = strtok(NULL, WHITESPACE))) { if (options->num_allow_users >= MAX_ALLOW_USERS) { fprintf(stderr, "%s line %d: too many allow users.\n", filename, linenum); exit(1); } options->allow_users[options->num_allow_users++] = xstrdup(cp); } break; case sDenyUsers: while ((cp = strtok(NULL, WHITESPACE))) { if (options->num_deny_users >= MAX_DENY_USERS) { fprintf(stderr, "%s line %d: too many deny users.\n", filename, linenum); exit(1); } options->deny_users[options->num_deny_users++] = xstrdup(cp); } break; case sAllowGroups: while ((cp = strtok(NULL, WHITESPACE))) { if (options->num_allow_groups >= MAX_ALLOW_GROUPS) { fprintf(stderr, "%s line %d: too many allow groups.\n", filename, linenum); exit(1); } options->allow_groups[options->num_allow_groups++] = xstrdup(cp); } break; case sDenyGroups: while ((cp = strtok(NULL, WHITESPACE))) { if (options->num_deny_groups >= MAX_DENY_GROUPS) { fprintf(stderr, "%s line %d: too many deny groups.\n", filename, linenum); exit(1); } options->deny_groups[options->num_deny_groups++] = xstrdup(cp); } break; case sXauthPath: charptr = &options->xauth_path; goto parse_pathname; case sCheckMail: intptr = &options->check_mail; goto parse_flag; case sPasswordExpireWarningDays: intptr = &options->password_expire_warning_days; goto parse_int; case sAccountExpireWarningDays: intptr = &options->account_expire_warning_days; goto parse_int; #ifdef F_SECURE_COMMERCIAL #endif /* F_SECURE_COMMERCIAL */ default: fprintf(stderr, "%s line %d: Missing handler for opcode %s (%d)\n", filename, linenum, cp, opcode); exit(1); } if (strtok(NULL, WHITESPACE) != NULL) { fprintf(stderr, "%s line %d: garbage at end of line.\n", filename, linenum); exit(1); } } fclose(f); }
int process_server_config_line(ServerOptions *options, char *line, const char *filename, int linenum) { char *cp, **charptr, *arg, *p; int *intptr, value, i, n; ServerOpCodes opcode; cp = line; arg = strdelim(&cp); /* Ignore leading whitespace */ if (*arg == '\0') arg = strdelim(&cp); if (!arg || !*arg || *arg == '#') return 0; intptr = NULL; charptr = NULL; opcode = parse_token(arg, filename, linenum); switch (opcode) { /* Portable-specific options */ case sPAMAuthenticationViaKbdInt: intptr = &options->pam_authentication_via_kbd_int; goto parse_flag; /* Standard Options */ case sBadOption: return -1; case sPort: /* ignore ports from configfile if cmdline specifies ports */ if (options->ports_from_cmdline) return 0; if (options->listen_addrs != NULL) fatal("%s line %d: ports must be specified before " "ListenAddress.", filename, linenum); if (options->num_ports >= MAX_PORTS) fatal("%s line %d: too many ports.", filename, linenum); arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing port number.", filename, linenum); options->ports[options->num_ports++] = a2port(arg); if (options->ports[options->num_ports-1] == 0) fatal("%s line %d: Badly formatted port number.", filename, linenum); break; case sServerKeyBits: intptr = &options->server_key_bits; parse_int: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing integer value.", filename, linenum); value = atoi(arg); if (*intptr == -1) *intptr = value; break; case sLoginGraceTime: intptr = &options->login_grace_time; parse_time: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing time value.", filename, linenum); if ((value = convtime(arg)) == -1) fatal("%s line %d: invalid time value.", filename, linenum); if (*intptr == -1) *intptr = value; break; case sKeyRegenerationTime: intptr = &options->key_regeneration_time; goto parse_time; case sListenAddress: arg = strdelim(&cp); if (!arg || *arg == '\0' || strncmp(arg, "[]", 2) == 0) fatal("%s line %d: missing inet addr.", filename, linenum); if (*arg == '[') { if ((p = strchr(arg, ']')) == NULL) fatal("%s line %d: bad ipv6 inet addr usage.", filename, linenum); arg++; memmove(p, p+1, strlen(p+1)+1); } else if (((p = strchr(arg, ':')) == NULL) || (strchr(p+1, ':') != NULL)) { add_listen_addr(options, arg, 0); break; } if (*p == ':') { u_short port; p++; if (*p == '\0') fatal("%s line %d: bad inet addr:port usage.", filename, linenum); else { *(p-1) = '\0'; if ((port = a2port(p)) == 0) fatal("%s line %d: bad port number.", filename, linenum); add_listen_addr(options, arg, port); } } else if (*p == '\0') add_listen_addr(options, arg, 0); else fatal("%s line %d: bad inet addr usage.", filename, linenum); break; case sHostKeyFile: intptr = &options->num_host_key_files; if (*intptr >= MAX_HOSTKEYS) fatal("%s line %d: too many host keys specified (max %d).", filename, linenum, MAX_HOSTKEYS); charptr = &options->host_key_files[*intptr]; parse_filename: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing file name.", filename, linenum); if (*charptr == NULL) { *charptr = tilde_expand_filename(arg, getuid()); /* increase optional counter */ if (intptr != NULL) *intptr = *intptr + 1; } break; case sPidFile: charptr = &options->pid_file; goto parse_filename; case sPermitRootLogin: intptr = &options->permit_root_login; arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing yes/" "without-password/forced-commands-only/no " "argument.", filename, linenum); value = 0; /* silence compiler */ if (strcmp(arg, "without-password") == 0) value = PERMIT_NO_PASSWD; else if (strcmp(arg, "forced-commands-only") == 0) value = PERMIT_FORCED_ONLY; else if (strcmp(arg, "yes") == 0) value = PERMIT_YES; else if (strcmp(arg, "no") == 0) value = PERMIT_NO; else fatal("%s line %d: Bad yes/" "without-password/forced-commands-only/no " "argument: %s", filename, linenum, arg); if (*intptr == -1) *intptr = value; break; case sIgnoreRhosts: intptr = &options->ignore_rhosts; parse_flag: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: missing yes/no argument.", filename, linenum); value = 0; /* silence compiler */ if (strcmp(arg, "yes") == 0) value = 1; else if (strcmp(arg, "no") == 0) value = 0; else fatal("%s line %d: Bad yes/no argument: %s", filename, linenum, arg); if (*intptr == -1) *intptr = value; break; case sIgnoreUserKnownHosts: intptr = &options->ignore_user_known_hosts; goto parse_flag; case sRhostsAuthentication: intptr = &options->rhosts_authentication; goto parse_flag; case sRhostsRSAAuthentication: intptr = &options->rhosts_rsa_authentication; goto parse_flag; case sHostbasedAuthentication: intptr = &options->hostbased_authentication; goto parse_flag; case sHostbasedUsesNameFromPacketOnly: intptr = &options->hostbased_uses_name_from_packet_only; goto parse_flag; case sRSAAuthentication: intptr = &options->rsa_authentication; goto parse_flag; case sPubkeyAuthentication: intptr = &options->pubkey_authentication; goto parse_flag; #if defined(KRB4) || defined(KRB5) case sKerberosAuthentication: intptr = &options->kerberos_authentication; goto parse_flag; case sKerberosOrLocalPasswd: intptr = &options->kerberos_or_local_passwd; goto parse_flag; case sKerberosTicketCleanup: intptr = &options->kerberos_ticket_cleanup; goto parse_flag; #endif #if defined(AFS) || defined(KRB5) case sKerberosTgtPassing: intptr = &options->kerberos_tgt_passing; goto parse_flag; #endif #ifdef AFS case sAFSTokenPassing: intptr = &options->afs_token_passing; goto parse_flag; #endif case sPasswordAuthentication: intptr = &options->password_authentication; goto parse_flag; case sKbdInteractiveAuthentication: intptr = &options->kbd_interactive_authentication; goto parse_flag; case sChallengeResponseAuthentication: intptr = &options->challenge_response_authentication; goto parse_flag; case sPrintMotd: intptr = &options->print_motd; goto parse_flag; case sPrintLastLog: intptr = &options->print_lastlog; goto parse_flag; case sX11Forwarding: intptr = &options->x11_forwarding; goto parse_flag; case sX11DisplayOffset: intptr = &options->x11_display_offset; goto parse_int; case sX11UseLocalhost: intptr = &options->x11_use_localhost; goto parse_flag; case sXAuthLocation: charptr = &options->xauth_location; goto parse_filename; case sStrictModes: intptr = &options->strict_modes; goto parse_flag; case sKeepAlives: intptr = &options->keepalives; goto parse_flag; case sEmptyPasswd: intptr = &options->permit_empty_passwd; goto parse_flag; case sPermitUserEnvironment: intptr = &options->permit_user_env; goto parse_flag; case sUseLogin: intptr = &options->use_login; goto parse_flag; case sCompression: intptr = &options->compression; goto parse_flag; case sGatewayPorts: intptr = &options->gateway_ports; goto parse_flag; case sVerifyReverseMapping: intptr = &options->verify_reverse_mapping; goto parse_flag; case sLogFacility: intptr = (int *) &options->log_facility; arg = strdelim(&cp); value = log_facility_number(arg); if (value == SYSLOG_FACILITY_NOT_SET) fatal("%.200s line %d: unsupported log facility '%s'", filename, linenum, arg ? arg : "<NONE>"); if (*intptr == -1) *intptr = (SyslogFacility) value; break; case sLogLevel: intptr = (int *) &options->log_level; arg = strdelim(&cp); value = log_level_number(arg); if (value == SYSLOG_LEVEL_NOT_SET) fatal("%.200s line %d: unsupported log level '%s'", filename, linenum, arg ? arg : "<NONE>"); if (*intptr == -1) *intptr = (LogLevel) value; break; case sAllowTcpForwarding: intptr = &options->allow_tcp_forwarding; goto parse_flag; case sUsePrivilegeSeparation: intptr = &use_privsep; goto parse_flag; case sAllowUsers: while ((arg = strdelim(&cp)) && *arg != '\0') { if (options->num_allow_users >= MAX_ALLOW_USERS) fatal("%s line %d: too many allow users.", filename, linenum); options->allow_users[options->num_allow_users++] = xstrdup(arg); } break; case sDenyUsers: while ((arg = strdelim(&cp)) && *arg != '\0') { if (options->num_deny_users >= MAX_DENY_USERS) fatal( "%s line %d: too many deny users.", filename, linenum); options->deny_users[options->num_deny_users++] = xstrdup(arg); } break; case sAllowGroups: while ((arg = strdelim(&cp)) && *arg != '\0') { if (options->num_allow_groups >= MAX_ALLOW_GROUPS) fatal("%s line %d: too many allow groups.", filename, linenum); options->allow_groups[options->num_allow_groups++] = xstrdup(arg); } break; case sDenyGroups: while ((arg = strdelim(&cp)) && *arg != '\0') { if (options->num_deny_groups >= MAX_DENY_GROUPS) fatal("%s line %d: too many deny groups.", filename, linenum); options->deny_groups[options->num_deny_groups++] = xstrdup(arg); } break; case sCiphers: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing argument.", filename, linenum); if (!ciphers_valid(arg)) fatal("%s line %d: Bad SSH2 cipher spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (options->ciphers == NULL) options->ciphers = xstrdup(arg); break; case sMacs: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing argument.", filename, linenum); if (!mac_valid(arg)) fatal("%s line %d: Bad SSH2 mac spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (options->macs == NULL) options->macs = xstrdup(arg); break; case sProtocol: intptr = &options->protocol; arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing argument.", filename, linenum); value = proto_spec(arg); if (value == SSH_PROTO_UNKNOWN) fatal("%s line %d: Bad protocol spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*intptr == SSH_PROTO_UNKNOWN) *intptr = value; break; case sSubsystem: if (options->num_subsystems >= MAX_SUBSYSTEMS) { fatal("%s line %d: too many subsystems defined.", filename, linenum); } arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing subsystem name.", filename, linenum); for (i = 0; i < options->num_subsystems; i++) if (strcmp(arg, options->subsystem_name[i]) == 0) fatal("%s line %d: Subsystem '%s' already defined.", filename, linenum, arg); options->subsystem_name[options->num_subsystems] = xstrdup(arg); arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing subsystem command.", filename, linenum); options->subsystem_command[options->num_subsystems] = xstrdup(arg); options->num_subsystems++; break; case sMaxStartups: arg = strdelim(&cp); if (!arg || *arg == '\0') fatal("%s line %d: Missing MaxStartups spec.", filename, linenum); if ((n = sscanf(arg, "%d:%d:%d", &options->max_startups_begin, &options->max_startups_rate, &options->max_startups)) == 3) { if (options->max_startups_begin > options->max_startups || options->max_startups_rate > 100 || options->max_startups_rate < 1) fatal("%s line %d: Illegal MaxStartups spec.", filename, linenum); } else if (n != 1) fatal("%s line %d: Illegal MaxStartups spec.", filename, linenum); else options->max_startups = options->max_startups_begin; break; case sBanner: charptr = &options->banner; goto parse_filename; /* * These options can contain %X options expanded at * connect time, so that you can specify paths like: * * AuthorizedKeysFile /etc/ssh_keys/%u */ case sAuthorizedKeysFile: case sAuthorizedKeysFile2: charptr = (opcode == sAuthorizedKeysFile ) ? &options->authorized_keys_file : &options->authorized_keys_file2; goto parse_filename; case sClientAliveInterval: intptr = &options->client_alive_interval; goto parse_time; case sClientAliveCountMax: intptr = &options->client_alive_count_max; goto parse_int; case sDeprecated: log("%s line %d: Deprecated option %s", filename, linenum, arg); while (arg) arg = strdelim(&cp); break; default: fatal("%s line %d: Missing handler for opcode %s (%d)", filename, linenum, arg, opcode); } if ((arg = strdelim(&cp)) != NULL && *arg != '\0') fatal("%s line %d: garbage at end of line; \"%.200s\".", filename, linenum, arg); return 0; }
/* * Main program for the ssh client. */ int main(int ac, char **av) { int i, opt, exit_status; u_short fwd_port, fwd_host_port; char sfwd_port[6], sfwd_host_port[6]; char *p, *cp, buf[256]; struct stat st; struct passwd *pw; int dummy; extern int optind, optreset; extern char *optarg; __progname = get_progname(av[0]); init_rng(); /* * Save the original real uid. It will be needed later (uid-swapping * may clobber the real uid). */ original_real_uid = getuid(); original_effective_uid = geteuid(); /* * Use uid-swapping to give up root privileges for the duration of * option processing. We will re-instantiate the rights when we are * ready to create the privileged port, and will permanently drop * them when the port has been created (actually, when the connection * has been made, as we may need to create the port several times). */ PRIV_END; #ifdef HAVE_SETRLIMIT /* If we are installed setuid root be careful to not drop core. */ if (original_real_uid != original_effective_uid) { struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 0; if (setrlimit(RLIMIT_CORE, &rlim) < 0) fatal("setrlimit failed: %.100s", strerror(errno)); } #endif /* Get user data. */ pw = getpwuid(original_real_uid); if (!pw) { log("You don't exist, go away!"); exit(1); } /* Take a copy of the returned structure. */ pw = pwcopy(pw); /* * Set our umask to something reasonable, as some files are created * with the default umask. This will make them world-readable but * writable only by the owner, which is ok for all files for which we * don't set the modes explicitly. */ umask(022); /* Initialize option structure to indicate that no values have been set. */ initialize_options(&options); /* Parse command-line arguments. */ host = NULL; again: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:NPR:TVX")) != -1) { switch (opt) { case '1': options.protocol = SSH_PROTO_1; break; case '2': options.protocol = SSH_PROTO_2; break; case '4': IPv4or6 = AF_INET; break; case '6': IPv4or6 = AF_INET6; break; case 'n': stdin_null_flag = 1; break; case 'f': fork_after_authentication_flag = 1; stdin_null_flag = 1; break; case 'x': options.forward_x11 = 0; break; case 'X': options.forward_x11 = 1; break; case 'g': options.gateway_ports = 1; break; case 'P': /* deprecated */ options.use_privileged_port = 0; break; case 'a': options.forward_agent = 0; break; case 'A': options.forward_agent = 1; break; #ifdef AFS case 'k': options.kerberos_tgt_passing = 0; options.afs_token_passing = 0; break; #endif case 'i': if (stat(optarg, &st) < 0) { fprintf(stderr, "Warning: Identity file %s " "does not exist.\n", optarg); break; } if (options.num_identity_files >= SSH_MAX_IDENTITY_FILES) fatal("Too many identity files specified " "(max %d)", SSH_MAX_IDENTITY_FILES); options.identity_files[options.num_identity_files++] = xstrdup(optarg); break; case 'I': #ifdef SMARTCARD options.smartcard_device = xstrdup(optarg); #else fprintf(stderr, "no support for smartcards.\n"); #endif break; case 't': if (tty_flag) force_tty_flag = 1; tty_flag = 1; break; case 'v': if (0 == debug_flag) { debug_flag = 1; options.log_level = SYSLOG_LEVEL_DEBUG1; } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) { options.log_level++; break; } else fatal("Too high debugging level."); /* fallthrough */ case 'V': fprintf(stderr, "%s, SSH protocols %d.%d/%d.%d, OpenSSL 0x%8.8lx\n", SSH_VERSION, PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1, PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2, SSLeay()); if (opt == 'V') exit(0); break; case 'q': options.log_level = SYSLOG_LEVEL_QUIET; break; case 'e': if (optarg[0] == '^' && optarg[2] == 0 && (u_char) optarg[1] >= 64 && (u_char) optarg[1] < 128) options.escape_char = (u_char) optarg[1] & 31; else if (strlen(optarg) == 1) options.escape_char = (u_char) optarg[0]; else if (strcmp(optarg, "none") == 0) options.escape_char = SSH_ESCAPECHAR_NONE; else { fprintf(stderr, "Bad escape character '%s'.\n", optarg); exit(1); } break; case 'c': if (ciphers_valid(optarg)) { /* SSH2 only */ options.ciphers = xstrdup(optarg); options.cipher = SSH_CIPHER_ILLEGAL; } else { /* SSH1 only */ options.cipher = cipher_number(optarg); if (options.cipher == -1) { fprintf(stderr, "Unknown cipher type '%s'\n", optarg); exit(1); } if (options.cipher == SSH_CIPHER_3DES) options.ciphers = "3des-cbc"; else if (options.cipher == SSH_CIPHER_BLOWFISH) options.ciphers = "blowfish-cbc"; else options.ciphers = (char *)-1; } break; case 'm': if (mac_valid(optarg)) options.macs = xstrdup(optarg); else { fprintf(stderr, "Unknown mac type '%s'\n", optarg); exit(1); } break; case 'p': options.port = a2port(optarg); if (options.port == 0) { fprintf(stderr, "Bad port '%s'\n", optarg); exit(1); } break; case 'l': options.user = optarg; break; case 'L': case 'R': if (sscanf(optarg, "%5[0-9]:%255[^:]:%5[0-9]", sfwd_port, buf, sfwd_host_port) != 3 && sscanf(optarg, "%5[0-9]/%255[^/]/%5[0-9]", sfwd_port, buf, sfwd_host_port) != 3) { fprintf(stderr, "Bad forwarding specification '%s'\n", optarg); usage(); /* NOTREACHED */ } if ((fwd_port = a2port(sfwd_port)) == 0 || (fwd_host_port = a2port(sfwd_host_port)) == 0) { fprintf(stderr, "Bad forwarding port(s) '%s'\n", optarg); exit(1); } if (opt == 'L') add_local_forward(&options, fwd_port, buf, fwd_host_port); else if (opt == 'R') add_remote_forward(&options, fwd_port, buf, fwd_host_port); break; case 'D': fwd_port = a2port(optarg); if (fwd_port == 0) { fprintf(stderr, "Bad dynamic port '%s'\n", optarg); exit(1); } add_local_forward(&options, fwd_port, "socks4", 0); break; case 'C': options.compression = 1; break; case 'N': no_shell_flag = 1; no_tty_flag = 1; break; case 'T': no_tty_flag = 1; break; case 'o': dummy = 1; if (process_config_line(&options, host ? host : "", optarg, "command-line", 0, &dummy) != 0) exit(1); break; case 's': subsystem_flag = 1; break; case 'b': options.bind_address = optarg; break; case 'F': config = optarg; break; default: usage(); } } ac -= optind; av += optind; if (ac > 0 && !host && **av != '-') { if (strrchr(*av, '@')) { p = xstrdup(*av); cp = strrchr(p, '@'); if (cp == NULL || cp == p) usage(); options.user = p; *cp = '\0'; host = ++cp; } else host = *av; if (ac > 1) { optind = optreset = 1; goto again; } ac--, av++; } /* Check that we got a host name. */ if (!host) usage(); SSLeay_add_all_algorithms(); ERR_load_crypto_strings(); channel_set_af(IPv4or6); /* Initialize the command to execute on remote host. */ buffer_init(&command); /* * Save the command to execute on the remote host in a buffer. There * is no limit on the length of the command, except by the maximum * packet size. Also sets the tty flag if there is no command. */ if (!ac) { /* No command specified - execute shell on a tty. */ tty_flag = 1; if (subsystem_flag) { fprintf(stderr, "You must specify a subsystem to invoke.\n"); usage(); } } else { /* A command has been specified. Store it into the buffer. */ for (i = 0; i < ac; i++) { if (i) buffer_append(&command, " ", 1); buffer_append(&command, av[i], strlen(av[i])); } } /* Cannot fork to background if no command. */ if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag) fatal("Cannot fork into background without a command to execute."); /* Allocate a tty by default if no command specified. */ if (buffer_len(&command) == 0) tty_flag = 1; /* Force no tty */ if (no_tty_flag) tty_flag = 0; /* Do not allocate a tty if stdin is not a tty. */ if (!isatty(fileno(stdin)) && !force_tty_flag) { if (tty_flag) log("Pseudo-terminal will not be allocated because stdin is not a terminal."); tty_flag = 0; } /* * Initialize "log" output. Since we are the client all output * actually goes to stderr. */ log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, SYSLOG_FACILITY_USER, 1); /* * Read per-user configuration file. Ignore the system wide config * file if the user specifies a config file on the command line. */ if (config != NULL) { if (!read_config_file(config, host, &options)) fatal("Can't open user config file %.100s: " "%.100s", config, strerror(errno)); } else { snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE); (void)read_config_file(buf, host, &options); /* Read systemwide configuration file after use config. */ (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, &options); } /* Fill configuration defaults. */ fill_default_options(&options); /* reinit */ log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1); seed_rng(); if (options.user == NULL) options.user = xstrdup(pw->pw_name); if (options.hostname != NULL) host = options.hostname; if (options.proxy_command != NULL && strcmp(options.proxy_command, "none") == 0) options.proxy_command = NULL; /* Disable rhosts authentication if not running as root. */ #ifdef HAVE_CYGWIN /* Ignore uid if running under Windows */ if (!options.use_privileged_port) { #else if (original_effective_uid != 0 || !options.use_privileged_port) { #endif debug("Rhosts Authentication disabled, " "originating port will not be trusted."); options.rhosts_authentication = 0; } /* Open a connection to the remote host. */ if (ssh_connect(host, &hostaddr, options.port, IPv4or6, options.connection_attempts, #ifdef HAVE_CYGWIN options.use_privileged_port, #else original_effective_uid == 0 && options.use_privileged_port, #endif options.proxy_command) != 0) exit(1); /* * If we successfully made the connection, load the host private key * in case we will need it later for combined rsa-rhosts * authentication. This must be done before releasing extra * privileges, because the file is only readable by root. * If we cannot access the private keys, load the public keys * instead and try to execute the ssh-keysign helper instead. */ sensitive_data.nkeys = 0; sensitive_data.keys = NULL; sensitive_data.external_keysign = 0; if (options.rhosts_rsa_authentication || options.hostbased_authentication) { sensitive_data.nkeys = 3; sensitive_data.keys = xmalloc(sensitive_data.nkeys * sizeof(Key)); PRIV_START; sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, _PATH_HOST_KEY_FILE, "", NULL); sensitive_data.keys[1] = key_load_private_type(KEY_DSA, _PATH_HOST_DSA_KEY_FILE, "", NULL); sensitive_data.keys[2] = key_load_private_type(KEY_RSA, _PATH_HOST_RSA_KEY_FILE, "", NULL); PRIV_END; if (options.hostbased_authentication == 1 && sensitive_data.keys[0] == NULL && sensitive_data.keys[1] == NULL && sensitive_data.keys[2] == NULL) { sensitive_data.keys[1] = key_load_public( _PATH_HOST_DSA_KEY_FILE, NULL); sensitive_data.keys[2] = key_load_public( _PATH_HOST_RSA_KEY_FILE, NULL); sensitive_data.external_keysign = 1; } } /* * Get rid of any extra privileges that we may have. We will no * longer need them. Also, extra privileges could make it very hard * to read identity files and other non-world-readable files from the * user's home directory if it happens to be on a NFS volume where * root is mapped to nobody. */ seteuid(original_real_uid); setuid(original_real_uid); /* * Now that we are back to our own permissions, create ~/.ssh * directory if it doesn\'t already exist. */ snprintf(buf, sizeof buf, "%.100s%s%.100s", pw->pw_dir, strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); if (stat(buf, &st) < 0) if (mkdir(buf, 0700) < 0) error("Could not create directory '%.200s'.", buf); /* load options.identity_files */ load_public_identity_files(); /* Expand ~ in known host file names. */ /* XXX mem-leaks: */ options.system_hostfile = tilde_expand_filename(options.system_hostfile, original_real_uid); options.user_hostfile = tilde_expand_filename(options.user_hostfile, original_real_uid); options.system_hostfile2 = tilde_expand_filename(options.system_hostfile2, original_real_uid); options.user_hostfile2 = tilde_expand_filename(options.user_hostfile2, original_real_uid); signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ /* Log into the remote system. This never returns if the login fails. */ ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, pw); /* We no longer need the private host keys. Clear them now. */ if (sensitive_data.nkeys != 0) { for (i = 0; i < sensitive_data.nkeys; i++) { if (sensitive_data.keys[i] != NULL) { /* Destroys contents safely */ debug3("clear hostkey %d", i); key_free(sensitive_data.keys[i]); sensitive_data.keys[i] = NULL; } } xfree(sensitive_data.keys); } for (i = 0; i < options.num_identity_files; i++) { if (options.identity_files[i]) { xfree(options.identity_files[i]); options.identity_files[i] = NULL; } if (options.identity_keys[i]) { key_free(options.identity_keys[i]); options.identity_keys[i] = NULL; } } exit_status = compat20 ? ssh_session2() : ssh_session(); packet_close(); /* * Send SIGHUP to proxy command if used. We don't wait() in * case it hangs and instead rely on init to reap the child */ if (proxy_command_pid > 1) kill(proxy_command_pid, SIGHUP); return exit_status; } static void x11_get_proto(char **_proto, char **_data) { char line[512]; static char proto[512], data[512]; FILE *f; int got_data = 0, i; char *display; struct stat st; *_proto = proto; *_data = data; proto[0] = data[0] = '\0'; if (!options.xauth_location || (stat(options.xauth_location, &st) == -1)) { debug("No xauth program."); } else { if ((display = getenv("DISPLAY")) == NULL) { debug("x11_get_proto: DISPLAY not set"); return; } /* Try to get Xauthority information for the display. */ if (strncmp(display, "localhost:", 10) == 0) /* * Handle FamilyLocal case where $DISPLAY does * not match an authorization entry. For this we * just try "xauth list unix:displaynum.screennum". * XXX: "localhost" match to determine FamilyLocal * is not perfect. */ snprintf(line, sizeof line, "%s list unix:%s 2>" _PATH_DEVNULL, options.xauth_location, display+10); else snprintf(line, sizeof line, "%s list %.200s 2>" _PATH_DEVNULL, options.xauth_location, display); debug2("x11_get_proto: %s", line); f = popen(line, "r"); if (f && fgets(line, sizeof(line), f) && sscanf(line, "%*s %511s %511s", proto, data) == 2) got_data = 1; if (f) pclose(f); } /* * If we didn't get authentication data, just make up some * data. The forwarding code will check the validity of the * response anyway, and substitute this data. The X11 * server, however, will ignore this fake data and use * whatever authentication mechanisms it was using otherwise * for the local connection. */ if (!got_data) { u_int32_t rand = 0; log("Warning: No xauth data; using fake authentication data for X11 forwarding."); strlcpy(proto, "MIT-MAGIC-COOKIE-1", sizeof proto); for (i = 0; i < 16; i++) { if (i % 4 == 0) rand = arc4random(); snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", rand & 0xff); rand >>= 8; } }