=================================================================== RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/ssh/ssh.c,v retrieving revision 1.51.2.3 retrieving revision 1.51.2.4 diff -u -r1.51.2.3 -r1.51.2.4 --- src/usr.bin/ssh/ssh.c 2000/11/08 21:31:24 1.51.2.3 +++ src/usr.bin/ssh/ssh.c 2001/03/12 15:44:16 1.51.2.4 @@ -39,25 +39,34 @@ */ #include "includes.h" -RCSID("$OpenBSD: ssh.c,v 1.51.2.3 2000/11/08 21:31:24 jason Exp $"); +RCSID("$OpenBSD: ssh.c,v 1.51.2.4 2001/03/12 15:44:16 jason Exp $"); #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 "readconf.h" #include "uidswap.h" - -#include "ssh2.h" -#include "compat.h" #include "channels.h" #include "key.h" #include "authfd.h" #include "authfile.h" +#include "pathnames.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" extern char *__progname; @@ -70,10 +79,11 @@ /* Flag indicating whether a tty should be allocated */ int tty_flag = 0; +int no_tty_flag = 0; +int force_tty_flag = 0; /* don't exec a shell */ int no_shell_flag = 0; -int no_tty_flag = 0; /* * Flag indicating that nothing should be read from stdin. This can be set @@ -112,9 +122,6 @@ */ volatile int received_window_change_signal = 0; -/* Value of argv[0] (set in the main program). */ -char *av0; - /* Flag indicating whether we have a valid host private key loaded. */ int host_private_key_loaded = 0; @@ -127,21 +134,24 @@ /* command to be executed */ Buffer command; +/* Should we execute a command or invoke a subsystem? */ +int subsystem_flag = 0; + /* Prints a help message to the user. This function never returns. */ void -usage() +usage(void) { - fprintf(stderr, "Usage: %s [options] host [command]\n", av0); + 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 /dev/null.\n"); + fprintf(stderr, " -n Redirect input from " _PATH_DEVNULL ".\n"); fprintf(stderr, " -A Enable authentication agent forwarding.\n"); fprintf(stderr, " -a Disable authentication agent forwarding.\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 Enable X11 connection forwarding.\n"); fprintf(stderr, " -x Disable X11 connection forwarding.\n"); fprintf(stderr, " -i file Identity for RSA authentication (default: ~/.ssh/identity).\n"); fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n"); @@ -160,15 +170,17 @@ 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", av0); + 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, " -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, " -2 Force protocol version 2.\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"); exit(1); } @@ -210,8 +222,9 @@ exit(1); } -int ssh_session(void); -int ssh_session2(void); +int ssh_session(void); +int ssh_session2(void); +int guess_identity_file_type(const char *filename); /* * Main program for the ssh client. @@ -258,24 +271,12 @@ */ umask(022); - /* Save our own name. */ - av0 = av[0]; - /* Initialize option structure to indicate that no values have been set. */ initialize_options(&options); /* Parse command-line arguments. */ host = NULL; - /* If program name is not one of the standard names, use it as host name. */ - if (strchr(av0, '/')) - cp = strrchr(av0, '/') + 1; - else - cp = av0; - if (strcmp(cp, "rsh") && strcmp(cp, "ssh") && strcmp(cp, "rlogin") && - strcmp(cp, "slogin") && strcmp(cp, "remsh")) - host = cp; - for (optind = 1; optind < ac; optind++) { if (av[optind][0] != '-') { if (host) @@ -293,7 +294,7 @@ opt = av[optind][1]; if (!opt) usage(); - if (strchr("eilcpLRo", opt)) { /* options with arguments */ + if (strchr("eilcmpLRo", opt)) { /* options with arguments */ optarg = av[optind] + 2; if (strcmp(optarg, "") == 0) { if (optind >= ac - 1) @@ -306,6 +307,9 @@ optarg = NULL; } switch (opt) { + case '1': + options.protocol = SSH_PROTO_1; + break; case '2': options.protocol = SSH_PROTO_2; break; @@ -349,16 +353,17 @@ case 'i': if (stat(optarg, &st) < 0) { fprintf(stderr, "Warning: Identity file %s does not exist.\n", - optarg); + 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); + SSH_MAX_IDENTITY_FILES); + options.identity_files[options.num_identity_files++] = xstrdup(optarg); break; case 't': + if (tty_flag) + force_tty_flag = 1; tty_flag = 1; break; case 'v': @@ -373,11 +378,12 @@ } /* fallthrough */ case 'V': - fprintf(stderr, "SSH Version %s, protocol versions %d.%d/%d.%d.\n", + 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); - fprintf(stderr, "Compiled with SSL (0x%8.8lx).\n", SSLeay()); + PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2, + SSLeay()); if (opt == 'V') exit(0); break; @@ -386,10 +392,10 @@ break; case 'e': if (optarg[0] == '^' && optarg[2] == 0 && - (unsigned char) optarg[1] >= 64 && (unsigned char) optarg[1] < 128) - options.escape_char = (unsigned char) optarg[1] & 31; + (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 = (unsigned char) optarg[0]; + options.escape_char = (u_char) optarg[0]; else if (strcmp(optarg, "none") == 0) options.escape_char = -2; else { @@ -404,14 +410,28 @@ options.cipher = SSH_CIPHER_ILLEGAL; } else { /* SSH1 only */ - Cipher *c = cipher_by_name(optarg); - if (c == NULL || c->number < 0) { + options.cipher = cipher_number(optarg); + if (options.cipher == -1) { fprintf(stderr, "Unknown cipher type '%s'\n", optarg); exit(1); } - options.cipher = c->number; + if (options.cipher == SSH_CIPHER_3DES) { + options.ciphers = "3des-cbc"; + } else if (options.cipher == SSH_CIPHER_BLOWFISH) { + options.ciphers = "blowfish-cbc"; + } else { + options.ciphers = (char *)-1; + } } break; + case 'm': + if (mac_valid(optarg)) + options.macs = xstrdup(optarg); + else { + fprintf(stderr, "Unknown mac type '%s'\n", optarg); + exit(1); + } + break; case 'p': options.port = atoi(optarg); break; @@ -456,6 +476,9 @@ "command-line", 0, &dummy) != 0) exit(1); break; + case 's': + subsystem_flag = 1; + break; default: usage(); } @@ -466,6 +489,7 @@ usage(); SSLeay_add_all_algorithms(); + ERR_load_crypto_strings(); /* Initialize the command to execute on remote host. */ buffer_init(&command); @@ -478,6 +502,10 @@ if (optind == ac) { /* No command specified - execute shell on a tty. */ tty_flag = 1; + if (subsystem_flag) { + fprintf(stderr, "You must specify a subsystem to invoke."); + usage(); + } } else { /* A command has been specified. Store it into the buffer. */ @@ -496,20 +524,20 @@ if (buffer_len(&command) == 0) tty_flag = 1; + /* Force no tty*/ + if (no_tty_flag) + tty_flag = 0; /* Do not allocate a tty if stdin is not a tty. */ - if (!isatty(fileno(stdin))) { + if (!isatty(fileno(stdin)) && !force_tty_flag) { if (tty_flag) - fprintf(stderr, "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.\n"); tty_flag = 0; } - /* force */ - if (no_tty_flag) - tty_flag = 0; /* Get user data. */ pw = getpwuid(original_real_uid); if (!pw) { - fprintf(stderr, "You don't exist, go away!\n"); + log("You don't exist, go away!\n"); exit(1); } /* Take a copy of the returned structure. */ @@ -528,11 +556,11 @@ 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, SSH_USER_CONFFILE); + 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(HOST_CONFIG_FILE, host, &options); + read_config_file(_PATH_HOST_CONFIG_FILE, host, &options); /* Fill configuration defaults. */ fill_default_options(&options); @@ -540,20 +568,6 @@ /* reinit */ log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0); - /* check if RSA support exists */ - if ((options.protocol & SSH_PROTO_1) && - rsa_alive() == 0) { - log("%s: no RSA support in libssl and libcrypto. See ssl(8).", - __progname); - log("Disabling protocol version 1"); - options.protocol &= ~ (SSH_PROTO_1|SSH_PROTO_1_PREFERRED); - } - if (! options.protocol & (SSH_PROTO_1|SSH_PROTO_2)) { - fprintf(stderr, "%s: No protocol version available.\n", - __progname); - exit(1); - } - if (options.user == NULL) options.user = xstrdup(pw->pw_name); @@ -562,8 +576,9 @@ /* Disable rhosts authentication if not running as root. */ if (original_effective_uid != 0 || !options.use_privileged_port) { + debug("Rhosts Authentication disabled, " + "originating port will not be trusted."); options.rhosts_authentication = 0; - options.rhosts_rsa_authentication = 0; } /* * If using rsh has been selected, exec it now (without trying @@ -586,17 +601,13 @@ /* Restore our superuser privileges. */ restore_uid(); - /* - * Open a connection to the remote host. This needs root privileges - * if rhosts_{rsa_}authentication is enabled. - */ + /* Open a connection to the remote host. */ ok = ssh_connect(host, &hostaddr, options.port, - options.connection_attempts, - !options.rhosts_authentication && - !options.rhosts_rsa_authentication, - original_real_uid, - options.proxy_command); + options.connection_attempts, + original_effective_uid != 0 || !options.use_privileged_port, + original_real_uid, + options.proxy_command); /* * If we successfully made the connection, load the host private key @@ -607,9 +618,9 @@ if (ok && (options.protocol & SSH_PROTO_1)) { Key k; host_private_key = RSA_new(); - k.type = KEY_RSA; + k.type = KEY_RSA1; k.rsa = host_private_key; - if (load_private_key(HOST_KEY_FILE, "", &k, NULL)) + if (load_private_key(_PATH_HOST_KEY_FILE, "", &k, NULL)) host_private_key_loaded = 1; } /* @@ -633,7 +644,7 @@ * 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, SSH_USER_DIR); + snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_DIR); if (stat(buf, &st) < 0) if (mkdir(buf, 0700) < 0) error("Could not create directory '%.200s'.", buf); @@ -654,23 +665,23 @@ } exit(1); } - /* Expand ~ in options.identity_files. */ + /* Expand ~ in options.identity_files, known host file names. */ /* XXX mem-leaks */ - for (i = 0; i < options.num_identity_files; i++) + for (i = 0; i < options.num_identity_files; i++) { options.identity_files[i] = - tilde_expand_filename(options.identity_files[i], original_real_uid); - for (i = 0; i < options.num_identity_files2; i++) - options.identity_files2[i] = - tilde_expand_filename(options.identity_files2[i], original_real_uid); - /* Expand ~ in known host file names. */ - options.system_hostfile = tilde_expand_filename(options.system_hostfile, - original_real_uid); - options.user_hostfile = tilde_expand_filename(options.user_hostfile, - original_real_uid); - options.system_hostfile2 = tilde_expand_filename(options.system_hostfile2, - original_real_uid); - options.user_hostfile2 = tilde_expand_filename(options.user_hostfile2, - original_real_uid); + 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]); + } + options.system_hostfile = + tilde_expand_filename(options.system_hostfile, original_real_uid); + options.user_hostfile = + tilde_expand_filename(options.user_hostfile, original_real_uid); + options.system_hostfile2 = + tilde_expand_filename(options.system_hostfile2, original_real_uid); + options.user_hostfile2 = + tilde_expand_filename(options.user_hostfile2, original_real_uid); /* Log into the remote system. This never returns if the login fails. */ ssh_login(host_private_key_loaded, host_private_key, @@ -694,7 +705,7 @@ if (options.xauth_location) { /* Try to get Xauthority information for the display. */ - snprintf(line, sizeof line, "%.100s list %.200s 2>/dev/null", + snprintf(line, sizeof line, "%.100s list %.200s 2>" _PATH_DEVNULL, options.xauth_location, getenv("DISPLAY")); f = popen(line, "r"); if (f && fgets(line, sizeof(line), f) && @@ -724,16 +735,61 @@ } } +void +ssh_init_forwarding(void) +{ + int success = 0; + int i; + + /* 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); + success += channel_request_local_forwarding( + options.local_forwards[i].port, + options.local_forwards[i].host, + options.local_forwards[i].host_port, + options.gateway_ports); + } + 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); + } +} + +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) + options.forward_agent = 0; + else + ssh_close_authentication_socket(authfd); + } +} + int ssh_session(void) { int type; - int i; int plen; int interactive = 0; int have_tty = 0; struct winsize ws; - int authfd; char *cp; /* Enable compression if requested. */ @@ -815,16 +871,11 @@ } } /* Tell the packet module whether this is an interactive session. */ - packet_set_interactive(interactive, options.keepalives); + packet_set_interactive(interactive); - /* Clear agent forwarding if we don\'t have an agent. */ - authfd = ssh_get_authentication_socket(); - if (authfd < 0) - options.forward_agent = 0; - else - ssh_close_authentication_socket(authfd); - /* Request authentication agent forwarding if appropriate. */ + check_agent_present(); + if (options.forward_agent) { debug("Requesting authentication agent forwarding."); auth_request_forwarding(); @@ -835,28 +886,9 @@ if (type != SSH_SMSG_SUCCESS) log("Warning: Remote host denied authentication agent forwarding."); } - /* 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); - channel_request_local_forwarding(options.local_forwards[i].port, - options.local_forwards[i].host, - options.local_forwards[i].host_port, - options.gateway_ports); - } - /* 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); - } + /* Initiate port forwardings. */ + ssh_init_forwarding(); /* If requested, let ssh continue in the background. */ if (fork_after_authentication_flag) @@ -888,30 +920,27 @@ } void -init_local_fwd(void) +client_subsystem_reply(int type, int plen, void *ctxt) { - int i; - /* 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); - channel_request_local_forwarding(options.local_forwards[i].port, - options.local_forwards[i].host, - options.local_forwards[i].host_port, - options.gateway_ports); - } + int id, len; + + id = packet_get_int(); + len = buffer_len(&command); + len = MAX(len, 900); + packet_done(); + if (type == SSH2_MSG_CHANNEL_FAILURE) + fatal("Request for subsystem '%.*s' failed on channel %d", + len, buffer_ptr(&command), id); } -extern void client_set_session_ident(int id); - void -client_init(int id, void *arg) +ssh_session2_callback(int id, void *arg) { int len; - debug("client_init id %d arg %d", id, (int)arg); + int interactive = 0; + debug("client_init id %d arg %ld", id, (long)arg); + if (no_shell_flag) goto done; @@ -933,6 +962,7 @@ packet_put_int(ws.ws_ypixel); packet_put_cstring(""); /* XXX: encode terminal modes */ packet_send(); + interactive = 1; /* XXX wait for reply */ } if (options.forward_x11 && @@ -943,24 +973,42 @@ /* Request forwarding with authentication spoofing. */ debug("Requesting X11 forwarding with authentication spoofing."); x11_request_forwarding_with_spoofing(id, proto, data); + interactive = 1; /* XXX wait for reply */ } + check_agent_present(); + if (options.forward_agent) { + debug("Requesting authentication agent forwarding."); + channel_request_start(id, "auth-agent-req@openssh.com", 0); + packet_send(); + } + len = buffer_len(&command); if (len > 0) { if (len > 900) len = 900; - debug("Sending command: %.*s", len, buffer_ptr(&command)); - channel_request_start(id, "exec", 0); + if (subsystem_flag) { + debug("Sending subsystem: %.*s", len, 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)); + channel_request_start(id, "exec", 0); + } packet_put_string(buffer_ptr(&command), len); packet_send(); } else { channel_request(id, "shell", 0); } /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */ + done: /* register different callback, etc. XXX */ - client_set_session_ident(id); + packet_set_interactive(interactive); } int @@ -970,7 +1018,7 @@ int in, out, err; if (stdin_null_flag) { - in = open("/dev/null", O_RDONLY); + in = open(_PATH_DEVNULL, O_RDONLY); } else { in = dup(STDIN_FILENO); } @@ -988,9 +1036,9 @@ if (!isatty(err)) set_nonblock(err); - /* should be pre-session */ - init_local_fwd(); - + /* 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) @@ -1008,7 +1056,28 @@ xstrdup("client-session"), /*nonblock*/0); channel_open(id); - channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, client_init, (void *)0); + channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, + ssh_session2_callback, (void *)0); return client_loop(tty_flag, tty_flag ? options.escape_char : -1, id); +} + +int +guess_identity_file_type(const char *filename) +{ + struct stat st; + Key *public; + int type = KEY_RSA1; /* default */ + + if (stat(filename, &st) < 0) { + /* ignore this key */ + return KEY_UNSPEC; + } + public = key_new(type); + if (!load_public_key(filename, public, NULL)) { + /* ok, so we will assume this is 'some' key */ + type = KEY_UNSPEC; + } + key_free(public); + return type; }