X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/1783c29f7c603e9b91f1343d7333e04c99e1ea3a..51aeb6391cc9c2b87fcb58852603958c8da951f8:/ssh.c diff --git a/ssh.c b/ssh.c index 98854d20..117a0930 100644 --- a/ssh.c +++ b/ssh.c @@ -39,7 +39,7 @@ */ #include "includes.h" -RCSID("$OpenBSD: ssh.c,v 1.129 2001/07/11 16:29:59 markus Exp $"); +RCSID("$OpenBSD: ssh.c,v 1.164 2002/02/14 23:28:00 markus Exp $"); #include #include @@ -118,6 +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 @@ -128,14 +131,6 @@ 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; - /* Private host keys. */ struct { Key **keys; @@ -151,11 +146,6 @@ Buffer command; /* Should we execute a command or invoke a subsystem? */ int subsystem_flag = 0; -#ifdef SMARTCARD -/* Smartcard reader id */ -int sc_reader_num = -1; -#endif - /* Prints a help message to the user. This function never returns. */ static void @@ -165,6 +155,8 @@ usage(void) 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 @@ -174,6 +166,9 @@ usage(void) 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"); @@ -191,6 +186,7 @@ usage(void) 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"); @@ -252,13 +248,16 @@ static void load_public_identity_files(void); int main(int ac, char **av) { - int i, opt, exit_status, ok; + 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]; 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(); @@ -313,7 +312,7 @@ main(int ac, char **av) again: while ((opt = getopt(ac, av, - "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:I:L:NPR:TVX")) != -1) { + "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:NPR:TVX")) != -1) { switch (opt) { case '1': options.protocol = SSH_PROTO_1; @@ -373,7 +372,7 @@ again: break; case 'I': #ifdef SMARTCARD - sc_reader_num = atoi(optarg); + options.smartcard_device = xstrdup(optarg); #else fprintf(stderr, "no support for smartcards.\n"); #endif @@ -462,33 +461,31 @@ again: 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) { + 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", + "Bad forwarding specification '%s'\n", optarg); usage(); /* NOTREACHED */ } - 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) { + if ((fwd_port = a2port(sfwd_port)) == 0 || + (fwd_host_port = a2port(sfwd_host_port)) == 0) { fprintf(stderr, - "Bad forwarding specification '%s'.\n", - optarg); - usage(); - /* NOTREACHED */ + "Bad forwarding port(s) '%s'\n", optarg); + exit(1); } - add_local_forward(&options, fwd_port, buf, - fwd_host_port); + 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': @@ -523,6 +520,9 @@ again: case 'b': options.bind_address = optarg; break; + case 'F': + config = optarg; + break; default: usage(); } @@ -556,6 +556,7 @@ again: SSLeay_add_all_algorithms(); ERR_load_crypto_strings(); + channel_set_af(IPv4or6); /* Initialize the command to execute on remote host. */ buffer_init(&command); @@ -607,12 +608,22 @@ again: log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, SYSLOG_FACILITY_USER, 1); - /* Read per-user configuration file. */ - snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE); - read_config_file(buf, host, &options); - - /* 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); @@ -662,7 +673,7 @@ again: /* 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, pw, options.proxy_command); @@ -675,7 +686,7 @@ again: */ sensitive_data.nkeys = 0; sensitive_data.keys = NULL; - if (ok && (options.rhosts_rsa_authentication || + if (!cerr && (options.rhosts_rsa_authentication || options.hostbased_authentication)) { sensitive_data.nkeys = 3; sensitive_data.keys = xmalloc(sensitive_data.nkeys*sizeof(Key)); @@ -707,26 +718,25 @@ again: * 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 (cerr) { + if (!options.fallback_to_rsh) + exit(1); 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" : ""); + log("Secure connection to %.100s on port %hu refused; " + "reverting to insecure method", + host, options.port); else - log("Secure connection to %.100s refused%.100s.", host, - options.fallback_to_rsh ? "; reverting to insecure method" : ""); + log("Secure connection to %.100s refused; " + "reverting to insecure method.", host); - if (options.fallback_to_rsh) { - rsh_connect(host, options.user, &command); - fatal("rsh_connect returned"); - } - exit(1); + rsh_connect(host, options.user, &command); + fatal("rsh_connect returned"); } /* load options.identity_files */ load_public_identity_files(); @@ -742,6 +752,8 @@ again: 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.keys, sensitive_data.nkeys, host, (struct sockaddr *)&hostaddr, pw); @@ -758,6 +770,16 @@ again: } 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(); @@ -765,19 +787,36 @@ again: } static void -x11_get_proto(char *proto, int proto_len, char *data, int data_len) +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, "%.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 %s %s", proto, data) == 2) + sscanf(line, "%*s %511s %511s", proto, data) == 2) got_data = 1; if (f) pclose(f); @@ -793,11 +832,11 @@ 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; } } @@ -815,7 +854,7 @@ 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, @@ -854,7 +893,6 @@ static int ssh_session(void) { int type; - int plen; int interactive = 0; int have_tty = 0; struct winsize ws; @@ -872,7 +910,7 @@ 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) @@ -910,7 +948,7 @@ ssh_session(void) 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; @@ -921,15 +959,15 @@ 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) { @@ -949,8 +987,8 @@ 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."); } @@ -971,7 +1009,7 @@ 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(); @@ -989,7 +1027,7 @@ ssh_session(void) } static void -client_subsystem_reply(int type, int plen, void *ctxt) +client_subsystem_reply(int type, u_int32_t seq, void *ctxt) { int id, len; @@ -997,20 +1035,21 @@ client_subsystem_reply(int type, int plen, void *ctxt) len = buffer_len(&command); if (len > 900) len = 900; - packet_done(); + 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); } +/* request pty/x11/agent/tcpfwd/shell for channel */ static void -ssh_session2_callback(int id, void *arg) +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); + debug("ssh_session2_setup: id %d", id); if (tty_flag) { struct winsize ws; @@ -1036,9 +1075,9 @@ ssh_session2_callback(int id, void *arg) } 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); @@ -1058,29 +1097,29 @@ 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 */ 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), 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); */ - /* register different callback, etc. XXX */ packet_set_interactive(interactive); } +/* open new channel for a session */ static int -ssh_session2_command(void) +ssh_session2_open(void) { Channel *c; int window, packetmax, in, out, err; @@ -1106,22 +1145,20 @@ ssh_session2_command(void) window = CHAN_SES_WINDOW_DEFAULT; packetmax = CHAN_SES_PACKET_DEFAULT; - if (!tty_flag) { - window *= 2; - packetmax *=2; + if (tty_flag) { + window >>= 1; + packetmax >>= 1; } c = channel_new( "session", SSH_CHANNEL_OPENING, in, out, err, window, packetmax, CHAN_EXTENDED_WRITE, xstrdup("client-session"), /*nonblock*/0); - if (c == NULL) - fatal("ssh_session2_command: channel_new failed"); - debug3("ssh_session2_command: channel_new: %d", c->self); + debug3("ssh_session2_open: channel_new: %d", c->self); channel_send_open(c->self); - channel_register_callback(c->self, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, - ssh_session2_callback, (void *)0); + if (!no_shell_flag) + channel_register_confirm(c->self, ssh_session2_setup); return c->self; } @@ -1129,12 +1166,13 @@ ssh_session2_command(void) static int ssh_session2(void) { - int id; + int id = -1; /* XXX should be pre-session */ ssh_init_forwarding(); - id = no_shell_flag ? -1 : ssh_session2_command(); + 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) @@ -1150,44 +1188,49 @@ load_public_identity_files(void) { char *filename; Key *public; - int i; + int i = 0; - for (i = 0; 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; - } #ifdef SMARTCARD - if (sc_reader_num != -1 && + if (options.smartcard_device != NULL && options.num_identity_files + 1 < SSH_MAX_IDENTITY_FILES && - (public = sc_get_key(sc_reader_num)) != NULL ) { + (public = sc_get_key(options.smartcard_device)) != NULL ) { Key *new; + if (options.num_identity_files + 2 > SSH_MAX_IDENTITY_FILES) + options.num_identity_files = SSH_MAX_IDENTITY_FILES - 2; + memmove(&options.identity_files[2], &options.identity_files[0], + sizeof(char *) * options.num_identity_files); + options.num_identity_files += 2; + i = 2; + /* XXX ssh1 vs ssh2 */ new = key_new(KEY_RSA); new->flags = KEY_FLAG_EXT; BN_copy(new->rsa->n, public->rsa->n); BN_copy(new->rsa->e, public->rsa->e); RSA_set_method(new->rsa, sc_get_engine()); - i = options.num_identity_files++; - options.identity_keys[i] = new; - options.identity_files[i] = xstrdup("smartcard rsa key");; + options.identity_keys[0] = new; + options.identity_files[0] = xstrdup("smartcard rsa key");; new = key_new(KEY_RSA1); new->flags = KEY_FLAG_EXT; BN_copy(new->rsa->n, public->rsa->n); BN_copy(new->rsa->e, public->rsa->e); RSA_set_method(new->rsa, sc_get_engine()); - i = options.num_identity_files++; - options.identity_keys[i] = new; - options.identity_files[i] = xstrdup("smartcard rsa1 key");; + options.identity_keys[1] = new; + options.identity_files[1] = xstrdup("smartcard rsa1 key"); key_free(public); } -#endif +#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; + } }