diff options
author | des <des@FreeBSD.org> | 2004-10-28 16:03:53 +0000 |
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committer | des <des@FreeBSD.org> | 2004-10-28 16:03:53 +0000 |
commit | d5d493f03ae792146848e3cba16bb9e667c73125 (patch) | |
tree | da81db150f0171c7861edf6e1f6b1fb45f81a6a7 /crypto/openssh/ssh.c | |
parent | c69db9c5a2d88a51f8d2394cf37717ba93f07152 (diff) | |
download | FreeBSD-src-d5d493f03ae792146848e3cba16bb9e667c73125.zip FreeBSD-src-d5d493f03ae792146848e3cba16bb9e667c73125.tar.gz |
Vendor import of OpenSSH 3.9p1.
Diffstat (limited to 'crypto/openssh/ssh.c')
-rw-r--r-- | crypto/openssh/ssh.c | 315 |
1 files changed, 243 insertions, 72 deletions
diff --git a/crypto/openssh/ssh.c b/crypto/openssh/ssh.c index e655e68..1419f98 100644 --- a/crypto/openssh/ssh.c +++ b/crypto/openssh/ssh.c @@ -40,7 +40,7 @@ */ #include "includes.h" -RCSID("$OpenBSD: ssh.c,v 1.209 2004/03/11 10:21:17 markus Exp $"); +RCSID("$OpenBSD: ssh.c,v 1.224 2004/07/28 09:40:29 markus Exp $"); #include <openssl/evp.h> #include <openssl/err.h> @@ -53,31 +53,31 @@ RCSID("$OpenBSD: ssh.c,v 1.209 2004/03/11 10:21:17 markus Exp $"); #include "xmalloc.h" #include "packet.h" #include "buffer.h" +#include "bufaux.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" #ifdef SMARTCARD #include "scard.h" #endif -#ifdef HAVE___PROGNAME extern char *__progname; -#else -char *__progname; -#endif /* Flag indicating whether debug mode is on. This can be set on the command line. */ int debug_flag = 0; @@ -141,16 +141,23 @@ 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; + +/* 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: ssh [-1246AaCfghkNnqsTtVvXxY] [-b bind_address] [-c cipher_spec]\n" +"usage: ssh [-1246AaCfghkMNnqsTtVvXxY] [-b bind_address] [-c cipher_spec]\n" " [-D port] [-e escape_char] [-F configfile] [-i identity_file]\n" " [-L port:host:hostport] [-l login_name] [-m mac_spec] [-o option]\n" -" [-p port] [-R port:host:hostport] [user@]hostname [command]\n" +" [-p port] [-R port:host:hostport] [-S ctl] [user@]hostname [command]\n" ); exit(1); } @@ -158,6 +165,7 @@ usage(void) 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. @@ -228,7 +236,7 @@ main(int ac, char **av) again: while ((opt = getopt(ac, av, - "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:NPR:TVXY")) != -1) { + "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:MNPR:S:TVXY")) != -1) { switch (opt) { case '1': options.protocol = SSH_PROTO_1; @@ -337,7 +345,7 @@ again: 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); @@ -364,6 +372,10 @@ again: exit(1); } break; + case 'M': + options.control_master = + (options.control_master >= 1) ? 2 : 1; + break; case 'p': options.port = a2port(optarg); if (options.port == 0) { @@ -432,6 +444,11 @@ again: 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; @@ -526,16 +543,17 @@ 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 { 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. */ @@ -565,6 +583,13 @@ again: strcmp(options.proxy_command, "none") == 0) options.proxy_command = NULL; + if (options.control_path != NULL) { + options.control_path = tilde_expand_filename( + options.control_path, original_real_uid); + } + if (options.control_path != NULL && options.control_master == 0) + control_client(options.control_path); /* This doesn't return */ + /* Open a connection to the remote host. */ if (ssh_connect(host, &hostaddr, options.port, options.address_family, options.connection_attempts, @@ -620,8 +645,10 @@ again: * user's home directory if it happens to be on a NFS volume where * root is mapped to nobody. */ - seteuid(original_real_uid); - setuid(original_real_uid); + if (original_effective_uid == 0) { + PRIV_START; + permanently_set_uid(pw); + } /* * Now that we are back to our own permissions, create ~/.ssh @@ -677,6 +704,9 @@ again: exit_status = compat20 ? ssh_session2() : ssh_session(); packet_close(); + if (options.control_path != NULL && control_fd != -1) + unlink(options.control_path); + /* * Send SIGHUP to proxy command if used. We don't wait() in * case it hangs and instead rely on init to reap the child @@ -776,17 +806,17 @@ x11_get_proto(char **_proto, char **_data) * for the local connection. */ if (!got_data) { - u_int32_t rand = 0; + u_int32_t rnd = 0; logit("Warning: No xauth data; " "using fake authentication data for X11 forwarding."); strlcpy(proto, SSH_X11_PROTO, sizeof proto); for (i = 0; i < 16; i++) { if (i % 4 == 0) - rand = arc4random(); + rnd = arc4random(); snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", - rand & 0xff); - rand >>= 8; + rnd & 0xff); + rnd >>= 8; } } } @@ -973,7 +1003,7 @@ 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; @@ -1005,40 +1035,53 @@ client_global_request_reply_fwd(int type, u_int32_t seq, void *ctxt) options.remote_forwards[i].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; - debug2("ssh_session2_setup: id %d", id); + if (options.control_path == NULL || options.control_master <= 0) + 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)); + memset(&addr, '\0', sizeof(addr)); + addr.sun_family = AF_UNIX; + addr_len = offsetof(struct sockaddr_un, sun_path) + + strlen(options.control_path) + 1; - 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 */ + 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\n", __func__, strerror(errno)); + + old_umask = umask(0177); + if (bind(control_fd, (struct sockaddr*)&addr, addr_len) == -1) { + control_fd = -1; + if (errno == EINVAL) + fatal("ControlSocket %s already exists", + options.control_path); + else + fatal("%s bind(): %s\n", __func__, strerror(errno)); } - if (options.forward_x11 && - getenv("DISPLAY") != NULL) { + umask(old_umask); + + if (listen(control_fd, 64) == -1) + fatal("%s listen(): %s\n", __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; + + int interactive = tty_flag; + if (options.forward_x11 && getenv("DISPLAY") != NULL) { char *proto, *data; /* Get reasonable local authentication information. */ x11_get_proto(&proto, &data); @@ -1056,27 +1099,8 @@ 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 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, (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_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); } @@ -1122,7 +1146,7 @@ ssh_session2_open(void) 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; } @@ -1134,6 +1158,7 @@ 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(); @@ -1187,3 +1212,149 @@ 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; + char name[1024], *cp; + + strlcpy(name, env, sizeof(name)); + if ((cp = strchr(name, '=')) == NULL) + return (0); + + *cp = '\0'; + + 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, sock, exitval, num_env, addr_len; + Buffer m; + char *cp; + extern char **environ; + + 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) + fatal("Couldn't connect to %s: %s", path, strerror(errno)); + + if ((cp = getenv("TERM")) == NULL) + cp = ""; + + buffer_init(&m); + + /* Get PID of controlee */ + if (ssh_msg_recv(sock, &m) == -1) + fatal("%s: msg_recv", __func__); + if (buffer_get_char(&m) != 0) + fatal("%s: wrong version", __func__); + /* Connection allowed? */ + if (buffer_get_int(&m) != 1) + fatal("Connection to master denied"); + control_server_pid = buffer_get_int(&m); + + buffer_clear(&m); + buffer_put_int(&m, tty_flag); + buffer_put_int(&m, subsystem_flag); + buffer_put_cstring(&m, cp); + + 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, /* version */0, &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) != 0) + fatal("%s: master returned error", __func__); + buffer_free(&m); + + 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); +} |