X-Git-Url: http://andersk.mit.edu/gitweb/gssapi-openssh.git/blobdiff_plain/510132b69d4fdceca750f6de39b2be84c49006c8..3de1c8f8279938a454280ed3a7916aa74d3df679:/openssh/ssh.c diff --git a/openssh/ssh.c b/openssh/ssh.c index 8e4739a..6edb30f 100644 --- a/openssh/ssh.c +++ b/openssh/ssh.c @@ -1,3 +1,4 @@ +/* $OpenBSD: ssh.c,v 1.294 2006/10/06 02:29:19 djm Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -13,7 +14,7 @@ * called by a name other than "ssh" or "Secure Shell". * * Copyright (c) 1999 Niels Provos. All rights reserved. - * Copyright (c) 2000, 2001, 2002 Markus Friedl. All rights reserved. + * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved. * * Modified to work with SSL by Niels Provos * in Canada (German citizen). @@ -40,53 +41,71 @@ */ #include "includes.h" -RCSID("$OpenBSD: ssh.c,v 1.170 2002/04/22 21:04:52 markus Exp $"); + +#include +#ifdef HAVE_SYS_STAT_H +# include +#endif +#include +#include +#include +#include + +#include +#include +#include +#include +#ifdef HAVE_PATHS_H +#include +#endif +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include #include #include +#include "xmalloc.h" #include "ssh.h" #include "ssh1.h" #include "ssh2.h" #include "compat.h" #include "cipher.h" -#include "xmalloc.h" #include "packet.h" #include "buffer.h" -#include "uidswap.h" #include "channels.h" #include "key.h" #include "authfd.h" #include "authfile.h" #include "pathnames.h" +#include "dispatch.h" #include "clientloop.h" #include "log.h" #include "readconf.h" #include "sshconnect.h" -#include "tildexpand.h" -#include "dispatch.h" #include "misc.h" #include "kex.h" #include "mac.h" -#include "sshtty.h" +#include "sshpty.h" +#include "match.h" +#include "msg.h" +#include "monitor_fdpass.h" +#include "uidswap.h" +#include "version.h" #ifdef SMARTCARD #include "scard.h" #endif -#ifdef HAVE___PROGNAME extern char *__progname; -#else -char *__progname; -#endif - -/* Flag indicating whether IPv4 or IPv6. This can be set on the command line. - Default value is AF_UNSPEC means both IPv4 and IPv6. */ -#ifdef IPV4_DEFAULT -int IPv4or6 = AF_INET; -#else -int IPv4or6 = AF_UNSPEC; -#endif /* Flag indicating whether debug mode is on. This can be set on the command line. */ int debug_flag = 0; @@ -107,7 +126,7 @@ int stdin_null_flag = 0; /* * Flag indicating that ssh should fork after authentication. This is useful - * so that the pasphrase can be entered manually, and then ssh goes to the + * so that the passphrase can be entered manually, and then ssh goes to the * background. */ int fork_after_authentication_flag = 0; @@ -132,13 +151,11 @@ char *host; struct sockaddr_storage hostaddr; /* Private host keys. */ -struct { - Key **keys; - int nkeys; -} sensitive_data; +Sensitive sensitive_data; /* Original real UID. */ uid_t original_real_uid; +uid_t original_effective_uid; /* command to be executed */ Buffer command; @@ -149,101 +166,39 @@ int subsystem_flag = 0; /* # of replies received for global requests */ static int client_global_request_id = 0; +/* pid of proxycommand child process */ +pid_t proxy_command_pid = 0; + +/* fd to control socket */ +int control_fd = -1; + +/* Multiplexing control command */ +static u_int mux_command = 0; + +/* Only used in control client mode */ +volatile sig_atomic_t control_client_terminate = 0; +u_int control_server_pid = 0; + /* Prints a help message to the user. This function never returns. */ static void usage(void) { - fprintf(stderr, "Usage: %s [options] host [command]\n", __progname); - fprintf(stderr, "Options:\n"); - fprintf(stderr, " -l user Log in using this user name.\n"); - fprintf(stderr, " -n Redirect input from " _PATH_DEVNULL ".\n"); - fprintf(stderr, " -F config Config file (default: ~/%s).\n", - _PATH_SSH_USER_CONFFILE); - fprintf(stderr, " -A Enable authentication agent forwarding.\n"); - fprintf(stderr, " -a Disable authentication agent forwarding (default).\n"); -#ifdef AFS - fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n"); -#endif /* AFS */ - fprintf(stderr, " -X Enable X11 connection forwarding.\n"); - fprintf(stderr, " -x Disable X11 connection forwarding (default).\n"); - fprintf(stderr, " -i file Identity for public key authentication " - "(default: ~/.ssh/identity)\n"); -#ifdef SMARTCARD - fprintf(stderr, " -I reader Set smartcard reader.\n"); -#endif - fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n"); - fprintf(stderr, " -T Do not allocate a tty.\n"); - fprintf(stderr, " -v Verbose; display verbose debugging messages.\n"); - fprintf(stderr, " Multiple -v increases verbosity.\n"); - fprintf(stderr, " -V Display version number only.\n"); - fprintf(stderr, " -P Don't allocate a privileged port.\n"); - fprintf(stderr, " -q Quiet; don't display any warning messages.\n"); - fprintf(stderr, " -f Fork into background after authentication.\n"); - fprintf(stderr, " -e char Set escape character; ``none'' = disable (default: ~).\n"); - - fprintf(stderr, " -c cipher Select encryption algorithm\n"); - fprintf(stderr, " -m macs Specify MAC algorithms for protocol version 2.\n"); - fprintf(stderr, " -p port Connect to this port. Server must be on the same port.\n"); - fprintf(stderr, " -L listen-port:host:port Forward local port to remote address\n"); - fprintf(stderr, " -R listen-port:host:port Forward remote port to local address\n"); - fprintf(stderr, " These cause %s to listen for connections on a port, and\n", __progname); - fprintf(stderr, " forward them to the other side by connecting to host:port.\n"); - fprintf(stderr, " -D port Enable dynamic application-level port forwarding.\n"); - fprintf(stderr, " -C Enable compression.\n"); - fprintf(stderr, " -N Do not execute a shell or command.\n"); - fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n"); - fprintf(stderr, " -1 Force protocol version 1.\n"); - fprintf(stderr, " -2 Force protocol version 2.\n"); - fprintf(stderr, " -4 Use IPv4 only.\n"); - fprintf(stderr, " -6 Use IPv6 only.\n"); - fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n"); - fprintf(stderr, " -s Invoke command (mandatory) as SSH2 subsystem.\n"); - fprintf(stderr, " -b addr Local IP address.\n"); - exit(1); -} - -/* - * Connects to the given host using rsh (or prints an error message and exits - * if rsh is not available). This function never returns. - */ -static void -rsh_connect(char *host, char *user, Buffer * command) -{ - char *args[10]; - int i; - - log("Using rsh. WARNING: Connection will not be encrypted."); - /* Build argument list for rsh. */ - i = 0; - args[i++] = _PATH_RSH; - /* host may have to come after user on some systems */ - args[i++] = host; - if (user) { - args[i++] = "-l"; - args[i++] = user; - } - if (buffer_len(command) > 0) { - buffer_append(command, "\0", 1); - args[i++] = buffer_ptr(command); - } - args[i++] = NULL; - if (debug_flag) { - for (i = 0; args[i]; i++) { - if (i != 0) - fprintf(stderr, " "); - fprintf(stderr, "%s", args[i]); - } - fprintf(stderr, "\n"); - } - execv(_PATH_RSH, args); - perror(_PATH_RSH); - exit(1); + fprintf(stderr, +"usage: ssh [-1246AaCfgkMNnqsTtVvXxY] [-b bind_address] [-c cipher_spec]\n" +" [-D [bind_address:]port] [-e escape_char] [-F configfile]\n" +" [-i identity_file] [-L [bind_address:]port:host:hostport]\n" +" [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n" +" [-R [bind_address:]port:host:hostport] [-S ctl_path]\n" +" [-w local_tun[:remote_tun]] [user@]hostname [command]\n" + ); + exit(255); } static int ssh_session(void); static int ssh_session2(void); static void load_public_identity_files(void); +static void control_client(const char *path); /* * Main program for the ssh client. @@ -251,18 +206,20 @@ static void load_public_identity_files(void); int main(int ac, char **av) { - int i, opt, exit_status, cerr; - u_short fwd_port, fwd_host_port; - char sfwd_port[6], sfwd_host_port[6]; - char *p, *cp, buf[256]; + int i, opt, exit_status; + char *p, *cp, *line, buf[256]; struct stat st; struct passwd *pw; int dummy; - uid_t original_effective_uid; 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 = get_progname(av[0]); + __progname = ssh_get_progname(av[0]); init_rng(); /* @@ -272,6 +229,15 @@ main(int ac, char **av) 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) { @@ -284,21 +250,12 @@ main(int ac, char **av) /* Get user data. */ pw = getpwuid(original_real_uid); if (!pw) { - log("You don't exist, go away!"); - exit(1); + logit("You don't exist, go away!"); + exit(255); } /* Take a copy of the returned structure. */ pw = pwcopy(pw); - /* - * 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). - */ - temporarily_use_uid(pw); - /* * Set our umask to something reasonable, as some files are created * with the default umask. This will make them world-readable but @@ -313,9 +270,9 @@ main(int ac, char **av) /* Parse command-line arguments. */ host = NULL; -again: + again: while ((opt = getopt(ac, av, - "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:NPR:TVX")) != -1) { + "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:MNO:PR:S:TVw:XY")) != -1) { switch (opt) { case '1': options.protocol = SSH_PROTO_1; @@ -324,10 +281,10 @@ again: options.protocol = SSH_PROTO_2; break; case '4': - IPv4or6 = AF_INET; + options.address_family = AF_INET; break; case '6': - IPv4or6 = AF_INET6; + options.address_family = AF_INET6; break; case 'n': stdin_null_flag = 1; @@ -342,10 +299,22 @@ again: case 'X': options.forward_x11 = 1; break; + case 'Y': + options.forward_x11 = 1; + options.forward_x11_trusted = 1; + break; case 'g': options.gateway_ports = 1; break; - case 'P': + case 'O': + if (strcmp(optarg, "check") == 0) + mux_command = SSHMUX_COMMAND_ALIVE_CHECK; + else if (strcmp(optarg, "exit") == 0) + mux_command = SSHMUX_COMMAND_TERMINATE; + else + fatal("Invalid multiplex command."); + break; + case 'P': /* deprecated */ options.use_privileged_port = 0; break; case 'a': @@ -354,16 +323,14 @@ again: case 'A': options.forward_agent = 1; break; -#ifdef AFS case 'k': - options.kerberos_tgt_passing = 0; - options.afs_token_passing = 0; + options.gss_deleg_creds = 0; break; -#endif case 'i': if (stat(optarg, &st) < 0) { fprintf(stderr, "Warning: Identity file %s " - "does not exist.\n", optarg); + "not accessible: %s.\n", optarg, + strerror(errno)); break; } if (options.num_identity_files >= @@ -386,25 +353,30 @@ again: tty_flag = 1; break; case 'v': - if (0 == debug_flag) { + if (debug_flag == 0) { debug_flag = 1; options.log_level = SYSLOG_LEVEL_DEBUG1; - } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) { - options.log_level++; + } else { + if (options.log_level < SYSLOG_LEVEL_DEBUG3) + options.log_level++; break; - } else - fatal("Too high debugging level."); - /* fallthrough */ + } + /* 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()); + 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 'q': options.log_level = SYSLOG_LEVEL_QUIET; break; @@ -420,14 +392,14 @@ again: else { fprintf(stderr, "Bad escape character '%s'.\n", optarg); - exit(1); + exit(255); } break; case 'c': if (ciphers_valid(optarg)) { /* SSH2 only */ options.ciphers = xstrdup(optarg); - options.cipher = SSH_CIPHER_ILLEGAL; + options.cipher = SSH_CIPHER_INVALID; } else { /* SSH1 only */ options.cipher = cipher_number(optarg); @@ -435,7 +407,7 @@ again: fprintf(stderr, "Unknown cipher type '%s'\n", optarg); - exit(1); + exit(255); } if (options.cipher == SSH_CIPHER_3DES) options.ciphers = "3des-cbc"; @@ -451,14 +423,20 @@ again: else { fprintf(stderr, "Unknown mac type '%s'\n", optarg); - exit(1); + 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(1); + exit(255); } break; case 'l': @@ -466,39 +444,51 @@ again: 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) { + if (parse_forward(&fwd, optarg)) + add_local_forward(&options, &fwd); + else { fprintf(stderr, - "Bad forwarding specification '%s'\n", + "Bad local forwarding specification '%s'\n", optarg); - usage(); - /* NOTREACHED */ + exit(255); } - if ((fwd_port = a2port(sfwd_port)) == 0 || - (fwd_host_port = a2port(sfwd_host_port)) == 0) { + break; + + case 'R': + if (parse_forward(&fwd, optarg)) { + add_remote_forward(&options, &fwd); + } else { fprintf(stderr, - "Bad forwarding port(s) '%s'\n", optarg); - exit(1); + "Bad remote forwarding specification " + "'%s'\n", optarg); + exit(255); } - 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) { + cp = p = xstrdup(optarg); + memset(&fwd, '\0', sizeof(fwd)); + fwd.connect_host = "socks"; + if ((fwd.listen_host = hpdelim(&cp)) == NULL) { + fprintf(stderr, "Bad dynamic forwarding " + "specification '%.100s'\n", optarg); + exit(255); + } + if (cp != NULL) { + fwd.listen_port = a2port(cp); + fwd.listen_host = cleanhostname(fwd.listen_host); + } else { + fwd.listen_port = a2port(fwd.listen_host); + fwd.listen_host = NULL; + } + + if (fwd.listen_port == 0) { fprintf(stderr, "Bad dynamic port '%s'\n", optarg); - exit(1); + exit(255); } - add_local_forward(&options, fwd_port, "socks4", 0); + add_local_forward(&options, &fwd); + xfree(p); break; case 'C': @@ -508,18 +498,29 @@ again: no_shell_flag = 1; no_tty_flag = 1; break; - case 'T': - no_tty_flag = 1; - break; case 'o': dummy = 1; + line = xstrdup(optarg); if (process_config_line(&options, host ? host : "", - optarg, "command-line", 0, &dummy) != 0) - exit(1); + line, "command-line", 0, &dummy) != 0) + exit(255); + xfree(line); + break; + case 'T': + no_tty_flag = 1; + /* ensure that the user doesn't try to backdoor a */ + /* null cipher switch on an interactive session */ + /* so explicitly disable it no matter what */ + options.none_switch=0; 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; @@ -535,9 +536,9 @@ again: av += optind; if (ac > 0 && !host && **av != '-') { - if (strchr(*av, '@')) { + if (strrchr(*av, '@')) { p = xstrdup(*av); - cp = strchr(p, '@'); + cp = strrchr(p, '@'); if (cp == NULL || cp == p) usage(); options.user = p; @@ -545,12 +546,11 @@ again: host = ++cp; } else host = *av; - ac--, av++; - if (ac > 0) { - optind = 0; - optreset = 1; + if (ac > 1) { + optind = optreset = 1; goto again; } + ac--, av++; } /* Check that we got a host name. */ @@ -559,7 +559,6 @@ again: SSLeay_add_all_algorithms(); ERR_load_crypto_strings(); - channel_set_af(IPv4or6); /* Initialize the command to execute on remote host. */ buffer_init(&command); @@ -594,13 +593,13 @@ again: if (buffer_len(&command) == 0) tty_flag = 1; - /* Force no tty*/ + /* 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 ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) { if (tty_flag) - log("Pseudo-terminal will not be allocated because stdin is not a terminal."); + logit("Pseudo-terminal will not be allocated because stdin is not a terminal."); tty_flag = 0; } @@ -616,92 +615,145 @@ again: * file if the user specifies a config file on the command line. */ if (config != NULL) { - if (!read_config_file(config, host, &options)) + if (!read_config_file(config, host, &options, 0)) fatal("Can't open user config file %.100s: " "%.100s", config, strerror(errno)); } else { + /* + * Since the config file parsing code aborts if it sees + * options it doesn't recognize, allow users to put + * options specific to compile-time add-ons in alternate + * config files so their primary config file will + * interoperate SSH versions that don't support those + * options. + */ +#ifdef GSSAPI + snprintf(buf, sizeof buf, "%.100s/%.100s.gssapi", pw->pw_dir, + _PATH_SSH_USER_CONFFILE); + (void)read_config_file(buf, host, &options, 1); +#ifdef GSI + snprintf(buf, sizeof buf, "%.100s/%.100s.gsi", pw->pw_dir, + _PATH_SSH_USER_CONFFILE); + (void)read_config_file(buf, host, &options, 1); +#endif +#if defined(KRB5) + snprintf(buf, sizeof buf, "%.100s/%.100s.krb", pw->pw_dir, + _PATH_SSH_USER_CONFFILE); + (void)read_config_file(buf, host, &options, 1); +#endif +#endif snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE); - (void)read_config_file(buf, host, &options); + (void)read_config_file(buf, host, &options, 1); /* Read systemwide configuration file after use config. */ - (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, &options); + (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(av[0], options.log_level, SYSLOG_FACILITY_USER, 1); seed_rng(); - if (options.user == NULL) { - options.user = xstrdup(pw->pw_name); - options.implicit = 1; - } + if (options.user == NULL) { + options.user = xstrdup(pw->pw_name); + options.implicit = 1; + } else options.implicit = 0; if (options.hostname != NULL) host = options.hostname; - /* 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; + /* 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 using rsh has been selected, exec it now (without trying - * anything else). Note that we must release privileges first. - */ - if (options.use_rsh) { - /* - * Restore our superuser privileges. This must be done - * before permanently setting the uid. - */ - restore_uid(); - - /* Switch to the original uid permanently. */ - permanently_set_uid(pw); - /* Execute rsh. */ - rsh_connect(host, options.user, &command); - fatal("rsh_connect returned"); + /* 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; } - /* Restore our superuser privileges. */ - restore_uid(); - /* Open a connection to the remote host. */ + if (options.proxy_command != NULL && + strcmp(options.proxy_command, "none") == 0) + options.proxy_command = NULL; + if (options.control_path != NULL && + strcmp(options.control_path, "none") == 0) + options.control_path = NULL; + + if (options.control_path != NULL) { + char thishost[NI_MAXHOST]; - cerr = ssh_connect(host, &hostaddr, options.port, IPv4or6, - options.connection_attempts, - original_effective_uid != 0 || !options.use_privileged_port, - pw, options.proxy_command); + if (gethostname(thishost, sizeof(thishost)) == -1) + fatal("gethostname: %s", strerror(errno)); + snprintf(buf, sizeof(buf), "%d", options.port); + cp = tilde_expand_filename(options.control_path, + original_real_uid); + options.control_path = percent_expand(cp, "p", buf, "h", host, + "r", options.user, "l", thishost, (char *)NULL); + xfree(cp); + } + if (mux_command != 0 && options.control_path == NULL) + fatal("No ControlPath specified for \"-O\" command"); + if (options.control_path != NULL) + control_client(options.control_path); + + /* Open a connection to the remote host. */ + if (ssh_connect(host, &hostaddr, options.port, + options.address_family, 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(255); /* * 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; - if (!cerr && (options.rhosts_rsa_authentication || - options.hostbased_authentication)) { + 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)); + sensitive_data.keys = xcalloc(sensitive_data.nkeys, + sizeof(Key)); + + PRIV_START; sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, - _PATH_HOST_KEY_FILE, "", NULL); + _PATH_HOST_KEY_FILE, "", NULL, NULL); sensitive_data.keys[1] = key_load_private_type(KEY_DSA, - _PATH_HOST_DSA_KEY_FILE, "", NULL); + _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL); sensitive_data.keys[2] = key_load_private_type(KEY_RSA, - _PATH_HOST_RSA_KEY_FILE, "", NULL); + _PATH_HOST_RSA_KEY_FILE, "", NULL, 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 @@ -710,40 +762,20 @@ again: * user's home directory if it happens to be on a NFS volume where * root is mapped to nobody. */ - - /* - * Note that some legacy systems need to postpone the following call - * to permanently_set_uid() until the private hostkey is destroyed - * with RSA_free(). Otherwise the calling user could ptrace() the - * process, read the private hostkey and impersonate the host. - * OpenBSD does not allow ptracing of setuid processes. - */ - permanently_set_uid(pw); + 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. + * 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); - /* Check if the connection failed, and try "rsh" if appropriate. */ - if (cerr) { - if (!options.fallback_to_rsh) - exit(1); - if (options.port != 0) - log("Secure connection to %.100s on port %hu refused; " - "reverting to insecure method", - host, options.port); - else - log("Secure connection to %.100s refused; " - "reverting to insecure method.", host); - - rsh_connect(host, options.user, &command); - fatal("rsh_connect returned"); - } /* load options.identity_files */ load_public_identity_files(); @@ -761,8 +793,7 @@ again: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ /* Log into the remote system. This never returns if the login fails. */ - ssh_login(sensitive_data.keys, sensitive_data.nkeys, - host, (struct sockaddr *)&hostaddr, pw); + 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) { @@ -789,63 +820,18 @@ again: exit_status = compat20 ? ssh_session2() : ssh_session(); packet_close(); - 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; - - *_proto = proto; - *_data = data; - proto[0] = data[0] = '\0'; - if (options.xauth_location && (display = getenv("DISPLAY"))) { - /* 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, "%.100s list unix:%s 2>" - _PATH_DEVNULL, options.xauth_location, display+10); - else - snprintf(line, sizeof line, "%.100s 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 (options.control_path != NULL && control_fd != -1) + unlink(options.control_path); + /* - * 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. + * 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 (!got_data) { - u_int32_t rand = 0; - - 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; - } - } + if (proxy_command_pid > 1) + kill(proxy_command_pid, SIGHUP); + + return exit_status; } static void @@ -856,29 +842,47 @@ ssh_init_forwarding(void) /* Initiate local TCP/IP port forwardings. */ for (i = 0; i < options.num_local_forwards; i++) { - debug("Connections to local port %d forwarded to remote address %.200s:%d", - options.local_forwards[i].port, - options.local_forwards[i].host, - options.local_forwards[i].host_port); + debug("Local connections to %.200s:%d forwarded to remote " + "address %.200s:%d", + (options.local_forwards[i].listen_host == NULL) ? + (options.gateway_ports ? "*" : "LOCALHOST") : + options.local_forwards[i].listen_host, + options.local_forwards[i].listen_port, + options.local_forwards[i].connect_host, + options.local_forwards[i].connect_port); success += channel_setup_local_fwd_listener( - options.local_forwards[i].port, - options.local_forwards[i].host, - options.local_forwards[i].host_port, - options.gateway_ports); + options.local_forwards[i].listen_host, + options.local_forwards[i].listen_port, + options.local_forwards[i].connect_host, + options.local_forwards[i].connect_port, + options.gateway_ports, options.hpn_disabled, + options.hpn_buffer_size); } + if (i > 0 && success != i && options.exit_on_forward_failure) + fatal("Could not request local forwarding."); if (i > 0 && success == 0) error("Could not request local forwarding."); /* Initiate remote TCP/IP port forwardings. */ for (i = 0; i < options.num_remote_forwards; i++) { - debug("Connections to remote port %d forwarded to local address %.200s:%d", - options.remote_forwards[i].port, - options.remote_forwards[i].host, - options.remote_forwards[i].host_port); - channel_request_remote_forwarding( - options.remote_forwards[i].port, - options.remote_forwards[i].host, - options.remote_forwards[i].host_port); + debug("Remote connections from %.200s:%d forwarded to " + "local address %.200s:%d", + (options.remote_forwards[i].listen_host == NULL) ? + "LOCALHOST" : options.remote_forwards[i].listen_host, + options.remote_forwards[i].listen_port, + options.remote_forwards[i].connect_host, + options.remote_forwards[i].connect_port); + if (channel_request_remote_forwarding( + options.remote_forwards[i].listen_host, + options.remote_forwards[i].listen_port, + options.remote_forwards[i].connect_host, + options.remote_forwards[i].connect_port) < 0) { + if (options.exit_on_forward_failure) + fatal("Could not request remote forwarding."); + else + logit("Warning: Could not request remote " + "forwarding."); + } } } @@ -886,12 +890,9 @@ static void check_agent_present(void) { if (options.forward_agent) { - /* Clear agent forwarding if we don\'t have an agent. */ - int authfd = ssh_get_authentication_socket(); - if (authfd < 0) + /* Clear agent forwarding if we don't have an agent. */ + if (!ssh_agent_present()) options.forward_agent = 0; - else - ssh_close_authentication_socket(authfd); } } @@ -903,6 +904,7 @@ ssh_session(void) int have_tty = 0; struct winsize ws; char *cp; + const char *display; /* Enable compression if requested. */ if (options.compression) { @@ -920,7 +922,7 @@ ssh_session(void) if (type == SSH_SMSG_SUCCESS) packet_start_compression(options.compression_level); else if (type == SSH_SMSG_FAILURE) - log("Warning: Remote host refused compression."); + logit("Warning: Remote host refused compression."); else packet_disconnect("Protocol error waiting for compression response."); } @@ -941,10 +943,10 @@ ssh_session(void) /* Store window size in the packet. */ if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) memset(&ws, 0, sizeof(ws)); - packet_put_int(ws.ws_row); - packet_put_int(ws.ws_col); - packet_put_int(ws.ws_xpixel); - packet_put_int(ws.ws_ypixel); + packet_put_int((u_int)ws.ws_row); + packet_put_int((u_int)ws.ws_col); + packet_put_int((u_int)ws.ws_xpixel); + packet_put_int((u_int)ws.ws_ypixel); /* Store tty modes in the packet. */ tty_make_modes(fileno(stdin), NULL); @@ -959,25 +961,27 @@ ssh_session(void) interactive = 1; have_tty = 1; } else if (type == SSH_SMSG_FAILURE) - log("Warning: Remote host failed or refused to allocate a pseudo tty."); + logit("Warning: Remote host failed or refused to allocate a pseudo tty."); else packet_disconnect("Protocol error waiting for pty request response."); } /* Request X11 forwarding if enabled and DISPLAY is set. */ - if (options.forward_x11 && getenv("DISPLAY") != NULL) { + display = getenv("DISPLAY"); + if (options.forward_x11 && display != NULL) { char *proto, *data; /* Get reasonable local authentication information. */ - x11_get_proto(&proto, &data); + client_x11_get_proto(display, options.xauth_location, + options.forward_x11_trusted, &proto, &data); /* Request forwarding with authentication spoofing. */ debug("Requesting X11 forwarding with authentication spoofing."); - x11_request_forwarding_with_spoofing(0, proto, data); + x11_request_forwarding_with_spoofing(0, display, proto, data); /* Read response from the server. */ type = packet_read(); if (type == SSH_SMSG_SUCCESS) { interactive = 1; } else if (type == SSH_SMSG_FAILURE) { - log("Warning: Remote host denied X11 forwarding."); + logit("Warning: Remote host denied X11 forwarding."); } else { packet_disconnect("Protocol error waiting for X11 forwarding"); } @@ -996,7 +1000,7 @@ ssh_session(void) type = packet_read(); packet_check_eom(); if (type != SSH_SMSG_SUCCESS) - log("Warning: Remote host denied authentication agent forwarding."); + logit("Warning: Remote host denied authentication agent forwarding."); } /* Initiate port forwardings. */ @@ -1033,7 +1037,7 @@ ssh_session(void) } static void -client_subsystem_reply(int type, u_int32_t seq, void *ctxt) +ssh_subsystem_reply(int type, u_int32_t seq, void *ctxt) { int id, len; @@ -1048,66 +1052,89 @@ client_subsystem_reply(int type, u_int32_t seq, void *ctxt) } void -client_global_request_reply(int type, u_int32_t seq, void *ctxt) +client_global_request_reply_fwd(int type, u_int32_t seq, void *ctxt) { int i; i = client_global_request_id++; - if (i >= options.num_remote_forwards) { - debug("client_global_request_reply: too many replies %d > %d", - i, options.num_remote_forwards); + if (i >= options.num_remote_forwards) return; - } debug("remote forward %s for: listen %d, connect %s:%d", type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", - options.remote_forwards[i].port, - options.remote_forwards[i].host, - options.remote_forwards[i].host_port); - if (type == SSH2_MSG_REQUEST_FAILURE) - log("Warning: remote port forwarding failed for listen port %d", - options.remote_forwards[i].port); + options.remote_forwards[i].listen_port, + options.remote_forwards[i].connect_host, + options.remote_forwards[i].connect_port); + if (type == SSH2_MSG_REQUEST_FAILURE) { + if (options.exit_on_forward_failure) + fatal("Error: remote port forwarding failed for " + "listen port %d", + options.remote_forwards[i].listen_port); + else + logit("Warning: remote port forwarding failed for " + "listen port %d", + options.remote_forwards[i].listen_port); + } } -/* request pty/x11/agent/tcpfwd/shell for channel */ static void -ssh_session2_setup(int id, void *arg) +ssh_control_listener(void) { - int len; - int interactive = 0; - struct termios tio; + struct sockaddr_un addr; + mode_t old_umask; + int addr_len; - debug("ssh_session2_setup: id %d", id); + if (options.control_path == NULL || + options.control_master == SSHCTL_MASTER_NO) + return; - if (tty_flag) { - struct winsize ws; - char *cp; - cp = getenv("TERM"); - if (!cp) - cp = ""; - /* Store window size in the packet. */ - if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) - memset(&ws, 0, sizeof(ws)); + debug("setting up multiplex master socket"); - channel_request_start(id, "pty-req", 0); - packet_put_cstring(cp); - packet_put_int(ws.ws_col); - packet_put_int(ws.ws_row); - packet_put_int(ws.ws_xpixel); - packet_put_int(ws.ws_ypixel); - tio = get_saved_tio(); - tty_make_modes(/*ignored*/ 0, &tio); - packet_send(); - interactive = 1; - /* XXX wait for reply */ + memset(&addr, '\0', sizeof(addr)); + addr.sun_family = AF_UNIX; + addr_len = offsetof(struct sockaddr_un, sun_path) + + strlen(options.control_path) + 1; + + if (strlcpy(addr.sun_path, options.control_path, + sizeof(addr.sun_path)) >= sizeof(addr.sun_path)) + fatal("ControlPath too long"); + + if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) + fatal("%s socket(): %s", __func__, strerror(errno)); + + old_umask = umask(0177); + if (bind(control_fd, (struct sockaddr *)&addr, addr_len) == -1) { + control_fd = -1; + if (errno == EINVAL || errno == EADDRINUSE) + fatal("ControlSocket %s already exists", + options.control_path); + else + fatal("%s bind(): %s", __func__, strerror(errno)); } - if (options.forward_x11 && - getenv("DISPLAY") != NULL) { + umask(old_umask); + + if (listen(control_fd, 64) == -1) + fatal("%s listen(): %s", __func__, strerror(errno)); + + set_nonblock(control_fd); +} + +/* request pty/x11/agent/tcpfwd/shell for channel */ +static void +ssh_session2_setup(int id, void *arg) +{ + extern char **environ; + const char *display; + int interactive = tty_flag; + + display = getenv("DISPLAY"); + if (options.forward_x11 && display != NULL) { char *proto, *data; /* Get reasonable local authentication information. */ - x11_get_proto(&proto, &data); + client_x11_get_proto(display, options.xauth_location, + options.forward_x11_trusted, &proto, &data); /* Request forwarding with authentication spoofing. */ debug("Requesting X11 forwarding with authentication spoofing."); - x11_request_forwarding_with_spoofing(id, proto, data); + x11_request_forwarding_with_spoofing(id, display, proto, data); interactive = 1; /* XXX wait for reply */ } @@ -1119,28 +1146,41 @@ ssh_session2_setup(int id, void *arg) packet_send(); } - len = buffer_len(&command); - if (len > 0) { - if (len > 900) - len = 900; - if (subsystem_flag) { - debug("Sending subsystem: %.*s", len, (u_char *)buffer_ptr(&command)); - channel_request_start(id, "subsystem", /*want reply*/ 1); - /* register callback for reply */ - /* XXX we asume that client_loop has already been called */ - dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &client_subsystem_reply); - dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &client_subsystem_reply); - } else { - debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command)); - channel_request_start(id, "exec", 0); + if (options.tun_open != SSH_TUNMODE_NO) { + Channel *c; + int fd; + + debug("Requesting tun."); + if ((fd = tun_open(options.tun_local, + options.tun_open)) >= 0) { + if(options.hpn_disabled) + c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1, + CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, + 0, "tun", 1); + else + c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1, + options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT, + 0, "tun", 1); + c->datagram = 1; +#if defined(SSH_TUN_FILTER) + if (options.tun_open == SSH_TUNMODE_POINTOPOINT) + channel_register_filter(c->self, sys_tun_infilter, + sys_tun_outfilter); +#endif + packet_start(SSH2_MSG_CHANNEL_OPEN); + packet_put_cstring("tun@openssh.com"); + packet_put_int(c->self); + packet_put_int(c->local_window_max); + packet_put_int(c->local_maxpacket); + packet_put_int(options.tun_open); + packet_put_int(options.tun_remote); + packet_send(); } - packet_put_string(buffer_ptr(&command), buffer_len(&command)); - packet_send(); - } else { - channel_request_start(id, "shell", 0); - packet_send(); } + client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"), + NULL, fileno(stdin), &command, environ, &ssh_subsystem_reply); + packet_set_interactive(interactive); } @@ -1150,6 +1190,9 @@ ssh_session2_open(void) { Channel *c; int window, packetmax, in, out, err; + int sock; + int socksize; + int socksizelen = sizeof(int); if (stdin_null_flag) { in = open(_PATH_DEVNULL, O_RDONLY); @@ -1170,22 +1213,86 @@ ssh_session2_open(void) if (!isatty(err)) set_nonblock(err); - window = CHAN_SES_WINDOW_DEFAULT; + /* we need to check to see if what they want to do about buffer */ + /* sizes here. In a hpn to nonhpn connection we want to limit */ + /* the window size to something reasonable in case the far side */ + /* has the large window bug. In hpn to hpn connection we want to */ + /* use the max window size but allow the user to override it */ + /* lastly if they disabled hpn then use the ssh std window size */ + + /* so why don't we just do a getsockopt() here and set the */ + /* ssh window to that? In the case of a autotuning receive */ + /* window the window would get stuck at the initial buffer */ + /* size generally less than 96k. Therefore we need to set the */ + /* maximum ssh window size to the maximum hpn buffer size */ + /* unless the user hasspecifically set the hpnrcvbufpoll */ + /* to no. In which case we *can* just set the window to the */ + /* minimum of the hpn buffer size and tcp receive buffer size */ + + if(options.hpn_disabled) + { + options.hpn_buffer_size = CHAN_SES_WINDOW_DEFAULT; + } + else if (datafellows & SSH_BUG_LARGEWINDOW) + { + debug("HPN to Non-HPN Connection"); + if (options.hpn_buffer_size < 0) + options.hpn_buffer_size = 2*1024*1024; + } + else + { + if (options.hpn_buffer_size < 0) + options.hpn_buffer_size = BUFFER_MAX_LEN_HPN; + + /*create a socket but don't connect it */ + /* we use that the get the rcv socket size */ + sock = socket(AF_INET, SOCK_STREAM, 0); + /* if they are using the tcp_rcv_buf option */ + /* attempt to set the buffer size to that */ + if (options.tcp_rcv_buf) + setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (void *)&options.tcp_rcv_buf, + sizeof(options.tcp_rcv_buf)); + getsockopt(sock, SOL_SOCKET, SO_RCVBUF, + &socksize, &socksizelen); + close(sock); + debug("socksize %d", socksize); + if (options.tcp_rcv_buf_poll <= 0) + { + options.hpn_buffer_size = MIN(socksize,options.hpn_buffer_size); + debug ("MIN of TCP RWIN and HPNBufferSize: %d", options.hpn_buffer_size); + } + else + { + if (options.tcp_rcv_buf > 0) + options.hpn_buffer_size = MIN(options.tcp_rcv_buf, options.hpn_buffer_size); + debug ("MIN of TCPRcvBuf and HPNBufferSize: %d", options.hpn_buffer_size); + } + + } + + debug("Final hpn_buffer_size = %d", options.hpn_buffer_size); + + window = options.hpn_buffer_size; + packetmax = CHAN_SES_PACKET_DEFAULT; if (tty_flag) { + window = 4*CHAN_SES_PACKET_DEFAULT; window >>= 1; packetmax >>= 1; } c = channel_new( "session", SSH_CHANNEL_OPENING, in, out, err, window, packetmax, CHAN_EXTENDED_WRITE, - xstrdup("client-session"), /*nonblock*/0); - + "client-session", /*nonblock*/0); + if ((options.tcp_rcv_buf_poll > 0) && (!options.hpn_disabled)) { + c->dynamic_window = 1; + debug ("Enabled Dynamic Window Scaling\n"); + } debug3("ssh_session2_open: channel_new: %d", c->self); channel_send_open(c->self); if (!no_shell_flag) - channel_register_confirm(c->self, ssh_session2_setup); + channel_register_confirm(c->self, ssh_session2_setup, NULL); return c->self; } @@ -1197,10 +1304,16 @@ ssh_session2(void) /* XXX should be pre-session */ ssh_init_forwarding(); + ssh_control_listener(); if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) id = ssh_session2_open(); + /* Execute a local command */ + if (options.local_command != NULL && + options.permit_local_command) + ssh_local_cmd(options.local_command); + /* If requested, let ssh continue in the background. */ if (fork_after_authentication_flag) if (daemon(1, 1) < 0) @@ -1213,15 +1326,16 @@ ssh_session2(void) static void load_public_identity_files(void) { - char *filename; + char *filename, *cp, thishost[NI_MAXHOST]; int i = 0; Key *public; + struct passwd *pw; #ifdef SMARTCARD Key **keys; if (options.smartcard_device != NULL && options.num_identity_files < SSH_MAX_IDENTITY_FILES && - (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL ) { + (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL) { int count = 0; for (i = 0; keys[i] != NULL; i++) { count++; @@ -1231,7 +1345,7 @@ load_public_identity_files(void) sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1)); options.num_identity_files++; options.identity_keys[0] = keys[i]; - options.identity_files[0] = xstrdup("smartcard key");; + options.identity_files[0] = sc_get_key_label(keys[i]); } if (options.num_identity_files > SSH_MAX_IDENTITY_FILES) options.num_identity_files = SSH_MAX_IDENTITY_FILES; @@ -1239,9 +1353,18 @@ load_public_identity_files(void) xfree(keys); } #endif /* SMARTCARD */ + if ((pw = getpwuid(original_real_uid)) == NULL) + fatal("load_public_identity_files: getpwuid failed"); + if (gethostname(thishost, sizeof(thishost)) == -1) + fatal("load_public_identity_files: gethostname: %s", + strerror(errno)); for (; i < options.num_identity_files; i++) { - filename = tilde_expand_filename(options.identity_files[i], + cp = tilde_expand_filename(options.identity_files[i], original_real_uid); + filename = percent_expand(cp, "d", pw->pw_dir, + "u", pw->pw_name, "l", thishost, "h", host, + "r", options.user, (char *)NULL); + xfree(cp); public = key_load_public(filename, NULL); debug("identity file %s type %d", filename, public ? public->type : -1); @@ -1250,3 +1373,226 @@ load_public_identity_files(void) options.identity_keys[i] = public; } } + +static void +control_client_sighandler(int signo) +{ + control_client_terminate = signo; +} + +static void +control_client_sigrelay(int signo) +{ + if (control_server_pid > 1) + kill(control_server_pid, signo); +} + +static int +env_permitted(char *env) +{ + int i, ret; + char name[1024], *cp; + + if ((cp = strchr(env, '=')) == NULL || cp == env) + return (0); + ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env); + if (ret <= 0 || (size_t)ret >= sizeof(name)) + fatal("env_permitted: name '%.100s...' too long", env); + + for (i = 0; i < options.num_send_env; i++) + if (match_pattern(name, options.send_env[i])) + return (1); + + return (0); +} + +static void +control_client(const char *path) +{ + struct sockaddr_un addr; + int i, r, fd, sock, exitval, num_env, addr_len; + Buffer m; + char *term; + extern char **environ; + u_int flags; + + if (mux_command == 0) + mux_command = SSHMUX_COMMAND_OPEN; + + switch (options.control_master) { + case SSHCTL_MASTER_AUTO: + case SSHCTL_MASTER_AUTO_ASK: + debug("auto-mux: Trying existing master"); + /* FALLTHROUGH */ + case SSHCTL_MASTER_NO: + break; + default: + return; + } + + memset(&addr, '\0', sizeof(addr)); + addr.sun_family = AF_UNIX; + addr_len = offsetof(struct sockaddr_un, sun_path) + + strlen(path) + 1; + + if (strlcpy(addr.sun_path, path, + sizeof(addr.sun_path)) >= sizeof(addr.sun_path)) + fatal("ControlPath too long"); + + if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) + fatal("%s socket(): %s", __func__, strerror(errno)); + + if (connect(sock, (struct sockaddr *)&addr, addr_len) == -1) { + if (mux_command != SSHMUX_COMMAND_OPEN) { + fatal("Control socket connect(%.100s): %s", path, + strerror(errno)); + } + if (errno == ENOENT) + debug("Control socket \"%.100s\" does not exist", path); + else { + error("Control socket connect(%.100s): %s", path, + strerror(errno)); + } + close(sock); + return; + } + + if (stdin_null_flag) { + if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1) + fatal("open(/dev/null): %s", strerror(errno)); + if (dup2(fd, STDIN_FILENO) == -1) + fatal("dup2: %s", strerror(errno)); + if (fd > STDERR_FILENO) + close(fd); + } + + term = getenv("TERM"); + + flags = 0; + if (tty_flag) + flags |= SSHMUX_FLAG_TTY; + if (subsystem_flag) + flags |= SSHMUX_FLAG_SUBSYS; + if (options.forward_x11) + flags |= SSHMUX_FLAG_X11_FWD; + if (options.forward_agent) + flags |= SSHMUX_FLAG_AGENT_FWD; + if (options.num_local_forwards > 0) + flags |= SSHMUX_FLAG_PORTFORWARD; + buffer_init(&m); + + /* Send our command to server */ + buffer_put_int(&m, mux_command); + buffer_put_int(&m, flags); + if (options.num_local_forwards > 0) + { + if (options.local_forwards[0].listen_host == NULL) + buffer_put_string(&m,"LOCALHOST",11); + else + buffer_put_string(&m,options.local_forwards[0].listen_host,512); + buffer_put_int(&m,options.local_forwards[0].listen_port); + buffer_put_string(&m,options.local_forwards[0].connect_host,512); + buffer_put_int(&m,options.local_forwards[0].connect_port); + } + if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1) + fatal("%s: msg_send", __func__); + buffer_clear(&m); + + /* Get authorisation status and PID of controlee */ + if (ssh_msg_recv(sock, &m) == -1) + fatal("%s: msg_recv", __func__); + if (buffer_get_char(&m) != SSHMUX_VER) + fatal("%s: wrong version", __func__); + if (buffer_get_int(&m) != 1) + fatal("Connection to master denied"); + control_server_pid = buffer_get_int(&m); + + buffer_clear(&m); + + switch (mux_command) { + case SSHMUX_COMMAND_ALIVE_CHECK: + fprintf(stderr, "Master running (pid=%d)\r\n", + control_server_pid); + exit(0); + case SSHMUX_COMMAND_TERMINATE: + fprintf(stderr, "Exit request sent.\r\n"); + exit(0); + case SSHMUX_COMMAND_OPEN: + /* continue below */ + break; + default: + fatal("silly mux_command %d", mux_command); + } + + /* SSHMUX_COMMAND_OPEN */ + buffer_put_cstring(&m, term ? term : ""); + buffer_append(&command, "\0", 1); + buffer_put_cstring(&m, buffer_ptr(&command)); + + if (options.num_send_env == 0 || environ == NULL) { + buffer_put_int(&m, 0); + } else { + /* Pass environment */ + num_env = 0; + for (i = 0; environ[i] != NULL; i++) + if (env_permitted(environ[i])) + num_env++; /* Count */ + + buffer_put_int(&m, num_env); + + for (i = 0; environ[i] != NULL && num_env >= 0; i++) + if (env_permitted(environ[i])) { + num_env--; + buffer_put_cstring(&m, environ[i]); + } + } + + if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1) + fatal("%s: msg_send", __func__); + + mm_send_fd(sock, STDIN_FILENO); + mm_send_fd(sock, STDOUT_FILENO); + mm_send_fd(sock, STDERR_FILENO); + + /* Wait for reply, so master has a chance to gather ttymodes */ + buffer_clear(&m); + if (ssh_msg_recv(sock, &m) == -1) + fatal("%s: msg_recv", __func__); + if (buffer_get_char(&m) != SSHMUX_VER) + fatal("%s: wrong version", __func__); + buffer_free(&m); + + signal(SIGHUP, control_client_sighandler); + signal(SIGINT, control_client_sighandler); + signal(SIGTERM, control_client_sighandler); + signal(SIGWINCH, control_client_sigrelay); + + if (tty_flag) + enter_raw_mode(); + + /* Stick around until the controlee closes the client_fd */ + exitval = 0; + for (;!control_client_terminate;) { + r = read(sock, &exitval, sizeof(exitval)); + if (r == 0) { + debug2("Received EOF from master"); + break; + } + if (r > 0) + debug2("Received exit status from master %d", exitval); + if (r == -1 && errno != EINTR) + fatal("%s: read %s", __func__, strerror(errno)); + } + + if (control_client_terminate) + debug2("Exiting on signal %d", control_client_terminate); + + close(sock); + + leave_raw_mode(); + + if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET) + fprintf(stderr, "Connection to master closed.\r\n"); + + exit(exitval); +}