X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/a01a5f3090014e2764d5d9576b178a004d75c256..ad2e1857ead440bc890368595899b6b51f1fe9bb:/ssh.c diff --git a/ssh.c b/ssh.c index cf6b0379..7cadc187 100644 --- a/ssh.c +++ b/ssh.c @@ -13,6 +13,7 @@ * 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. * * Modified to work with SSL by Niels Provos * in Canada (German citizen). @@ -39,7 +40,7 @@ */ #include "includes.h" -RCSID("$OpenBSD: ssh.c,v 1.99 2001/03/01 02:29:04 deraadt Exp $"); +RCSID("$OpenBSD: ssh.c,v 1.176 2002/06/08 05:17:01 markus Exp $"); #include #include @@ -67,6 +68,11 @@ RCSID("$OpenBSD: ssh.c,v 1.99 2001/03/01 02:29:04 deraadt Exp $"); #include "misc.h" #include "kex.h" #include "mac.h" +#include "sshtty.h" + +#ifdef SMARTCARD +#include "scard.h" +#endif #ifdef HAVE___PROGNAME extern char *__progname; @@ -101,7 +107,7 @@ 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; @@ -112,6 +118,9 @@ int fork_after_authentication_flag = 0; */ Options options; +/* optional user configfile */ +char *config = NULL; + /* * Name of the host we are connecting to. This is the name given on the * command line, or the HostName specified for the user-supplied name in a @@ -122,19 +131,8 @@ char *host; /* socket address the host resolves to */ struct sockaddr_storage hostaddr; -/* - * Flag to indicate that we have received a window change signal which has - * not yet been processed. This will cause a message indicating the new - * window size to be sent to the server a little later. This is volatile - * because this is updated in a signal handler. - */ -volatile int received_window_change_signal = 0; - -/* Flag indicating whether we have a valid host private key loaded. */ -int host_private_key_loaded = 0; - -/* Host private key. */ -RSA *host_private_key = NULL; +/* Private host keys. */ +Sensitive sensitive_data; /* Original real UID. */ uid_t original_real_uid; @@ -145,24 +143,32 @@ Buffer command; /* Should we execute a command or invoke a subsystem? */ int subsystem_flag = 0; +/* # of replies received for global requests */ +static int client_global_request_id = 0; + /* Prints a help message to the user. This function never returns. */ -void +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.\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.\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"); @@ -173,13 +179,14 @@ usage(void) 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: " - "``3des'', ``blowfish''\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"); @@ -189,50 +196,13 @@ usage(void) 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. - */ -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); -} - -int ssh_session(void); -int ssh_session2(void); -int guess_identity_file_type(const char *filename); +static int ssh_session(void); +static int ssh_session2(void); +static void load_public_identity_files(void); /* * Main program for the ssh client. @@ -240,13 +210,16 @@ int guess_identity_file_type(const char *filename); int main(int ac, char **av) { - int i, opt, optind, exit_status, ok; + int i, opt, exit_status, cerr; u_short fwd_port, fwd_host_port; - char *optarg, *cp, buf[256]; + char sfwd_port[6], sfwd_host_port[6]; + char *p, *cp, buf[256]; struct stat st; struct passwd *pw; int dummy; uid_t original_effective_uid; + extern int optind, optreset; + extern char *optarg; __progname = get_progname(av[0]); init_rng(); @@ -267,6 +240,15 @@ main(int ac, char **av) 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); + /* * Use uid-swapping to give up root privileges for the duration of * option processing. We will re-instantiate the rights when we are @@ -274,7 +256,7 @@ main(int ac, char **av) * 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(original_real_uid); + temporarily_use_uid(pw); /* * Set our umask to something reasonable, as some files are created @@ -290,35 +272,9 @@ main(int ac, char **av) /* Parse command-line arguments. */ host = NULL; - for (optind = 1; optind < ac; optind++) { - if (av[optind][0] != '-') { - if (host) - break; - if ((cp = strchr(av[optind], '@'))) { - if(cp == av[optind]) - usage(); - options.user = av[optind]; - *cp = '\0'; - host = ++cp; - } else - host = av[optind]; - continue; - } - opt = av[optind][1]; - if (!opt) - usage(); - if (strchr("eilcmpLRo", opt)) { /* options with arguments */ - optarg = av[optind] + 2; - if (strcmp(optarg, "") == 0) { - if (optind >= ac - 1) - usage(); - optarg = av[++optind]; - } - } else { - if (av[optind][2]) - usage(); - optarg = 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; @@ -365,14 +321,23 @@ main(int ac, char **av) #endif case 'i': if (stat(optarg, &st) < 0) { - fprintf(stderr, "Warning: Identity file %s does not exist.\n", - optarg); + 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); + 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) @@ -386,9 +351,8 @@ main(int ac, char **av) } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) { options.log_level++; break; - } else { - fatal("Too high debugging level.\n"); - } + } else + fatal("Too high debugging level."); /* fallthrough */ case 'V': fprintf(stderr, @@ -405,14 +369,16 @@ main(int ac, char **av) break; case 'e': if (optarg[0] == '^' && optarg[2] == 0 && - (u_char) optarg[1] >= 64 && (u_char) optarg[1] < 128) + (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 = -2; + options.escape_char = SSH_ESCAPECHAR_NONE; else { - fprintf(stderr, "Bad escape character '%s'.\n", optarg); + fprintf(stderr, "Bad escape character '%s'.\n", + optarg); exit(1); } break; @@ -425,54 +391,75 @@ main(int ac, char **av) /* SSH1 only */ options.cipher = cipher_number(optarg); if (options.cipher == -1) { - fprintf(stderr, "Unknown cipher type '%s'\n", optarg); + fprintf(stderr, + "Unknown cipher type '%s'\n", + optarg); exit(1); } - if (options.cipher == SSH_CIPHER_3DES) { + if (options.cipher == SSH_CIPHER_3DES) options.ciphers = "3des-cbc"; - } else if (options.cipher == SSH_CIPHER_BLOWFISH) { + else if (options.cipher == SSH_CIPHER_BLOWFISH) options.ciphers = "blowfish-cbc"; - } else { + 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); + fprintf(stderr, "Unknown mac type '%s'\n", + optarg); exit(1); } break; case 'p': - options.port = atoi(optarg); + 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, "%hu/%255[^/]/%hu", &fwd_port, buf, - &fwd_host_port) != 3 && - sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf, - &fwd_host_port) != 3) { - fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg); + 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 */ } - add_remote_forward(&options, fwd_port, buf, fwd_host_port); + 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 'L': - if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf, - &fwd_host_port) != 3 && - sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf, - &fwd_host_port) != 3) { - fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg); - usage(); - /* NOTREACHED */ + + 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, buf, fwd_host_port); + add_local_forward(&options, fwd_port, "socks4", 0); break; + case 'C': options.compression = 1; break; @@ -485,24 +472,53 @@ main(int ac, char **av) break; case 'o': dummy = 1; - if (process_config_line(&options, host ? host : "", optarg, - "command-line", 0, &dummy) != 0) + 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 (strchr(*av, '@')) { + p = xstrdup(*av); + cp = strchr(p, '@'); + if (cp == NULL || cp == p) + usage(); + options.user = p; + *cp = '\0'; + host = ++cp; + } else + host = *av; + ac--, av++; + if (ac > 0) { + optind = 0; + optreset = 1; + goto again; + } + } + /* 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); @@ -512,18 +528,18 @@ main(int ac, char **av) * 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 (optind == ac) { + 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."); + fprintf(stderr, + "You must specify a subsystem to invoke.\n"); usage(); } } else { - /* A command has been specified. Store it into the - buffer. */ - for (i = optind; i < ac; i++) { - if (i > optind) + /* 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])); } @@ -543,35 +559,41 @@ main(int ac, char **av) /* 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.\n"); + log("Pseudo-terminal will not be allocated because stdin is not a terminal."); tty_flag = 0; } - /* Get user data. */ - pw = getpwuid(original_real_uid); - if (!pw) { - log("You don't exist, go away!\n"); - exit(1); - } - /* Take a copy of the returned structure. */ - pw = pwcopy(pw); - - /* Initialize "log" output. Since we are the client all output - actually goes to the terminal. */ - log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0); - - /* Read per-user configuration file. */ - snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE); - read_config_file(buf, host, &options); + /* + * 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 systemwide configuration file. */ - read_config_file(_PATH_HOST_CONFIG_FILE, host, &options); + /* + * 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, 0); + log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1); + + seed_rng(); if (options.user == NULL) options.user = xstrdup(pw->pw_name); @@ -590,48 +612,47 @@ main(int ac, char **av) "originating port will not be trusted."); options.rhosts_authentication = 0; } - /* - * 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(original_real_uid); - - /* Execute rsh. */ - rsh_connect(host, options.user, &command); - fatal("rsh_connect returned"); - } /* Restore our superuser privileges. */ restore_uid(); /* Open a connection to the remote host. */ - ok = ssh_connect(host, &hostaddr, options.port, + cerr = ssh_connect(host, &hostaddr, options.port, IPv4or6, options.connection_attempts, original_effective_uid != 0 || !options.use_privileged_port, - original_real_uid, - options.proxy_command); + pw, options.proxy_command); /* * 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. */ - if (ok && (options.protocol & SSH_PROTO_1)) { - Key k; - host_private_key = RSA_new(); - k.type = KEY_RSA1; - k.rsa = host_private_key; - if (load_private_key(_PATH_HOST_KEY_FILE, "", &k, NULL)) - host_private_key_loaded = 1; + sensitive_data.nkeys = 0; + sensitive_data.keys = NULL; + sensitive_data.external_keysign = 0; + if (!cerr && (options.rhosts_rsa_authentication || + options.hostbased_authentication)) { + sensitive_data.nkeys = 3; + sensitive_data.keys = xmalloc(sensitive_data.nkeys*sizeof(Key)); + 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); + + if (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 @@ -640,50 +661,25 @@ main(int ac, char **av) * 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(original_real_uid); + permanently_set_uid(pw); /* * Now that we are back to our own permissions, create ~/.ssh * directory if it doesn\'t already exist. */ - snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_DIR); + 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 (!ok) { - if (options.port != 0) - log("Secure connection to %.100s on port %hu refused%.100s.", - host, options.port, - options.fallback_to_rsh ? "; reverting to insecure method" : ""); - else - log("Secure connection to %.100s refused%.100s.", host, - options.fallback_to_rsh ? "; reverting to insecure method" : ""); - - if (options.fallback_to_rsh) { - rsh_connect(host, options.user, &command); - fatal("rsh_connect returned"); - } + if (cerr) exit(1); - } - /* Expand ~ in options.identity_files, known host file names. */ - /* XXX mem-leaks */ - for (i = 0; i < options.num_identity_files; i++) { - options.identity_files[i] = - tilde_expand_filename(options.identity_files[i], original_real_uid); - options.identity_files_type[i] = guess_identity_file_type(options.identity_files[i]); - debug("identity file %s type %d", options.identity_files[i], - options.identity_files_type[i]); - } + + /* 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 = @@ -693,33 +689,70 @@ main(int ac, char **av) options.user_hostfile2 = tilde_expand_filename(options.user_hostfile2, original_real_uid); - /* Log into the remote system. This never returns if the login fails. */ - ssh_login(host_private_key_loaded, host_private_key, - host, (struct sockaddr *)&hostaddr, original_real_uid); + signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ - /* We no longer need the host private key. Clear it now. */ - if (host_private_key_loaded) - RSA_free(host_private_key); /* Destroys contents safely */ + /* 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(); return exit_status; } -void -x11_get_proto(char *proto, int proto_len, char *data, int data_len) +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; - if (options.xauth_location) { + *_proto = proto; + *_data = data; + proto[0] = data[0] = '\0'; + if (options.xauth_location && (display = getenv("DISPLAY"))) { /* Try to get Xauthority information for the display. */ - snprintf(line, sizeof line, "%.100s list %.200s 2>" _PATH_DEVNULL, - options.xauth_location, getenv("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 %s %s", proto, data) == 2) + sscanf(line, "%*s %511s %511s", proto, data) == 2) got_data = 1; if (f) pclose(f); @@ -735,17 +768,17 @@ x11_get_proto(char *proto, int proto_len, char *data, int data_len) if (!got_data) { u_int32_t rand = 0; - strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len); + strlcpy(proto, "MIT-MAGIC-COOKIE-1", sizeof proto); for (i = 0; i < 16; i++) { if (i % 4 == 0) rand = arc4random(); - snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff); + snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", rand & 0xff); rand >>= 8; } } } -void +static void ssh_init_forwarding(void) { int success = 0; @@ -757,7 +790,7 @@ ssh_init_forwarding(void) options.local_forwards[i].port, options.local_forwards[i].host, options.local_forwards[i].host_port); - success += channel_request_local_forwarding( + success += channel_setup_local_fwd_listener( options.local_forwards[i].port, options.local_forwards[i].host, options.local_forwards[i].host_port, @@ -779,7 +812,7 @@ ssh_init_forwarding(void) } } -void +static void check_agent_present(void) { if (options.forward_agent) { @@ -792,11 +825,10 @@ check_agent_present(void) } } -int +static int ssh_session(void) { int type; - int plen; int interactive = 0; int have_tty = 0; struct winsize ws; @@ -814,7 +846,7 @@ ssh_session(void) packet_put_int(options.compression_level); packet_send(); packet_write_wait(); - type = packet_read(&plen); + type = packet_read(); if (type == SSH_SMSG_SUCCESS) packet_start_compression(options.compression_level); else if (type == SSH_SMSG_FAILURE) @@ -834,7 +866,7 @@ ssh_session(void) cp = getenv("TERM"); if (!cp) cp = ""; - packet_put_string(cp, strlen(cp)); + packet_put_cstring(cp); /* Store window size in the packet. */ if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) @@ -845,14 +877,14 @@ ssh_session(void) packet_put_int(ws.ws_ypixel); /* Store tty modes in the packet. */ - tty_make_modes(fileno(stdin)); + tty_make_modes(fileno(stdin), NULL); /* Send the packet, and wait for it to leave. */ packet_send(); packet_write_wait(); /* Read response from the server. */ - type = packet_read(&plen); + type = packet_read(); if (type == SSH_SMSG_SUCCESS) { interactive = 1; have_tty = 1; @@ -863,15 +895,15 @@ ssh_session(void) } /* Request X11 forwarding if enabled and DISPLAY is set. */ if (options.forward_x11 && getenv("DISPLAY") != NULL) { - char proto[512], data[512]; + char *proto, *data; /* Get reasonable local authentication information. */ - x11_get_proto(proto, sizeof proto, data, sizeof data); + x11_get_proto(&proto, &data); /* Request forwarding with authentication spoofing. */ debug("Requesting X11 forwarding with authentication spoofing."); x11_request_forwarding_with_spoofing(0, proto, data); /* Read response from the server. */ - type = packet_read(&plen); + type = packet_read(); if (type == SSH_SMSG_SUCCESS) { interactive = 1; } else if (type == SSH_SMSG_FAILURE) { @@ -891,8 +923,8 @@ ssh_session(void) auth_request_forwarding(); /* Read response from the server. */ - type = packet_read(&plen); - packet_integrity_check(plen, 0, type); + type = packet_read(); + packet_check_eom(); if (type != SSH_SMSG_SUCCESS) log("Warning: Remote host denied authentication agent forwarding."); } @@ -913,7 +945,7 @@ ssh_session(void) int len = buffer_len(&command); if (len > 900) len = 900; - debug("Sending command: %.*s", len, buffer_ptr(&command)); + debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command)); packet_start(SSH_CMSG_EXEC_CMD); packet_put_string(buffer_ptr(&command), buffer_len(&command)); packet_send(); @@ -926,33 +958,55 @@ ssh_session(void) } /* Enter the interactive session. */ - return client_loop(have_tty, tty_flag ? options.escape_char : -1, 0); + return client_loop(have_tty, tty_flag ? + options.escape_char : SSH_ESCAPECHAR_NONE, 0); } -void -client_subsystem_reply(int type, int plen, void *ctxt) +static void +client_subsystem_reply(int type, u_int32_t seq, void *ctxt) { int id, len; id = packet_get_int(); len = buffer_len(&command); - len = MAX(len, 900); - packet_done(); + if (len > 900) + len = 900; + packet_check_eom(); if (type == SSH2_MSG_CHANNEL_FAILURE) fatal("Request for subsystem '%.*s' failed on channel %d", - len, buffer_ptr(&command), id); + len, (u_char *)buffer_ptr(&command), id); } void -ssh_session2_callback(int id, void *arg) +client_global_request_reply(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); + 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); +} + +/* request pty/x11/agent/tcpfwd/shell for channel */ +static void +ssh_session2_setup(int id, void *arg) { int len; int interactive = 0; + struct termios tio; - debug("client_init id %d arg %ld", id, (long)arg); - - if (no_shell_flag) - goto done; + debug("ssh_session2_setup: id %d", id); if (tty_flag) { struct winsize ws; @@ -970,16 +1024,17 @@ ssh_session2_callback(int id, void *arg) packet_put_int(ws.ws_row); packet_put_int(ws.ws_xpixel); packet_put_int(ws.ws_ypixel); - packet_put_cstring(""); /* XXX: encode terminal modes */ + tio = get_saved_tio(); + tty_make_modes(/*ignored*/ 0, &tio); packet_send(); interactive = 1; /* XXX wait for reply */ } if (options.forward_x11 && getenv("DISPLAY") != NULL) { - char proto[512], data[512]; + char *proto, *data; /* Get reasonable local authentication information. */ - x11_get_proto(proto, sizeof proto, data, sizeof data); + x11_get_proto(&proto, &data); /* Request forwarding with authentication spoofing. */ debug("Requesting X11 forwarding with authentication spoofing."); x11_request_forwarding_with_spoofing(id, proto, data); @@ -999,33 +1054,32 @@ ssh_session2_callback(int id, void *arg) if (len > 900) len = 900; if (subsystem_flag) { - debug("Sending subsystem: %.*s", len, buffer_ptr(&command)); + 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 */ + /* XXX we assume 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, buffer_ptr(&command)); + debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command)); channel_request_start(id, "exec", 0); } - packet_put_string(buffer_ptr(&command), len); + packet_put_string(buffer_ptr(&command), buffer_len(&command)); packet_send(); } else { - channel_request(id, "shell", 0); + channel_request_start(id, "shell", 0); + packet_send(); } - /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */ -done: - /* register different callback, etc. XXX */ packet_set_interactive(interactive); } -int -ssh_session2(void) +/* open new channel for a session */ +static int +ssh_session2_open(void) { - int window, packetmax, id; - int in, out, err; + Channel *c; + int window, packetmax, in, out, err; if (stdin_null_flag) { in = open(_PATH_DEVNULL, O_RDONLY); @@ -1046,48 +1100,83 @@ ssh_session2(void) if (!isatty(err)) set_nonblock(err); - /* XXX should be pre-session */ - ssh_init_forwarding(); - - /* If requested, let ssh continue in the background. */ - if (fork_after_authentication_flag) - if (daemon(1, 1) < 0) - fatal("daemon() failed: %.200s", strerror(errno)); - window = CHAN_SES_WINDOW_DEFAULT; packetmax = CHAN_SES_PACKET_DEFAULT; - if (!tty_flag) { - window *= 2; - packetmax *=2; + if (tty_flag) { + window >>= 1; + packetmax >>= 1; } - id = channel_new( + c = channel_new( "session", SSH_CHANNEL_OPENING, in, out, err, window, packetmax, CHAN_EXTENDED_WRITE, xstrdup("client-session"), /*nonblock*/0); - channel_open(id); - channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, - ssh_session2_callback, (void *)0); + debug3("ssh_session2_open: channel_new: %d", c->self); - return client_loop(tty_flag, tty_flag ? options.escape_char : -1, id); + channel_send_open(c->self); + if (!no_shell_flag) + channel_register_confirm(c->self, ssh_session2_setup); + + return c->self; } -int -guess_identity_file_type(const char *filename) +static int +ssh_session2(void) { - struct stat st; - Key *public; - int type = KEY_RSA1; /* default */ + int id = -1; - if (stat(filename, &st) < 0) { - /* ignore this key */ - return KEY_UNSPEC; + /* XXX should be pre-session */ + ssh_init_forwarding(); + + if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) + id = ssh_session2_open(); + + /* If requested, let ssh continue in the background. */ + if (fork_after_authentication_flag) + if (daemon(1, 1) < 0) + fatal("daemon() failed: %.200s", strerror(errno)); + + return client_loop(tty_flag, tty_flag ? + options.escape_char : SSH_ESCAPECHAR_NONE, id); +} + +static void +load_public_identity_files(void) +{ + char *filename; + int i = 0; + Key *public; +#ifdef SMARTCARD + Key **keys; + + if (options.smartcard_device != NULL && + options.num_identity_files < SSH_MAX_IDENTITY_FILES && + (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL ) { + int count = 0; + for (i = 0; keys[i] != NULL; i++) { + count++; + memmove(&options.identity_files[1], &options.identity_files[0], + sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1)); + memmove(&options.identity_keys[1], &options.identity_keys[0], + sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1)); + options.num_identity_files++; + options.identity_keys[0] = keys[i]; + options.identity_files[0] = xstrdup("smartcard key");; + } + if (options.num_identity_files > SSH_MAX_IDENTITY_FILES) + options.num_identity_files = SSH_MAX_IDENTITY_FILES; + i = count; + xfree(keys); } - public = key_new(type); - if (!load_public_key(filename, public, NULL)) { - /* ok, so we will assume this is 'some' key */ - type = KEY_UNSPEC; +#endif /* SMARTCARD */ + for (; i < options.num_identity_files; i++) { + filename = tilde_expand_filename(options.identity_files[i], + original_real_uid); + public = key_load_public(filename, NULL); + debug("identity file %s type %d", filename, + public ? public->type : -1); + xfree(options.identity_files[i]); + options.identity_files[i] = filename; + options.identity_keys[i] = public; } - key_free(public); - return type; }