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-rw-r--r--crypto/openssh/ssh.c1202
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diff --git a/crypto/openssh/ssh.c b/crypto/openssh/ssh.c
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+++ b/crypto/openssh/ssh.c
@@ -0,0 +1,1202 @@
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ * All rights reserved
+ * Ssh client program. This program can be used to log into a remote machine.
+ * The software supports strong authentication, encryption, and forwarding
+ * of X11, TCP/IP, and authentication connections.
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose. Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * 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 <provos@citi.umich.edu>
+ * in Canada (German citizen).
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: ssh.c,v 1.179 2002/06/12 01:09:52 markus Exp $");
+RCSID("$FreeBSD$");
+
+#include <openssl/evp.h>
+#include <openssl/err.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 "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"
+#include "sshtty.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;
+
+/* 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;
+
+/*
+ * Flag indicating that nothing should be read from stdin. This can be set
+ * on the command line.
+ */
+int stdin_null_flag = 0;
+
+/*
+ * Flag indicating that ssh should fork after authentication. This is useful
+ * so that the passphrase can be entered manually, and then ssh goes to the
+ * background.
+ */
+int fork_after_authentication_flag = 0;
+
+/*
+ * General data structure for command line options and options configurable
+ * in configuration files. See readconf.h.
+ */
+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
+ * configuration file.
+ */
+char *host;
+
+/* socket address the host resolves to */
+struct sockaddr_storage hostaddr;
+
+/* Private host keys. */
+Sensitive sensitive_data;
+
+/* Original real UID. */
+uid_t original_real_uid;
+uid_t original_effective_uid;
+
+/* command to be executed */
+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. */
+
+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);
+}
+
+static int ssh_session(void);
+static int ssh_session2(void);
+static void load_public_identity_files(void);
+
+/*
+ * Main program for the ssh client.
+ */
+int
+main(int ac, char **av)
+{
+ int i, opt, exit_status;
+ 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;
+ extern int optind, optreset;
+ extern char *optarg;
+
+ __progname = get_progname(av[0]);
+ init_rng();
+
+ /*
+ * Save the original real uid. It will be needed later (uid-swapping
+ * may clobber the real uid).
+ */
+ original_real_uid = getuid();
+ original_effective_uid = geteuid();
+
+#ifdef HAVE_SETRLIMIT
+ /* If we are installed setuid root be careful to not drop core. */
+ if (original_real_uid != original_effective_uid) {
+ struct rlimit rlim;
+ rlim.rlim_cur = rlim.rlim_max = 0;
+ if (setrlimit(RLIMIT_CORE, &rlim) < 0)
+ fatal("setrlimit failed: %.100s", strerror(errno));
+ }
+#endif
+ /* Get user data. */
+ pw = getpwuid(original_real_uid);
+ if (!pw) {
+ log("unknown user %d", original_real_uid);
+ 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
+ * 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;
+
+ /*
+ * Set our umask to something reasonable, as some files are created
+ * with the default umask. This will make them world-readable but
+ * writable only by the owner, which is ok for all files for which we
+ * don't set the modes explicitly.
+ */
+ umask(022);
+
+ /* Initialize option structure to indicate that no values have been set. */
+ initialize_options(&options);
+
+ /* Parse command-line arguments. */
+ host = 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;
+ break;
+ case '2':
+ options.protocol = SSH_PROTO_2;
+ break;
+ case '4':
+ IPv4or6 = AF_INET;
+ break;
+ case '6':
+ IPv4or6 = AF_INET6;
+ break;
+ case 'n':
+ stdin_null_flag = 1;
+ break;
+ case 'f':
+ fork_after_authentication_flag = 1;
+ stdin_null_flag = 1;
+ break;
+ case 'x':
+ options.forward_x11 = 0;
+ break;
+ case 'X':
+ options.forward_x11 = 1;
+ break;
+ case 'g':
+ options.gateway_ports = 1;
+ break;
+ case 'P':
+ options.use_privileged_port = 0;
+ break;
+ case 'a':
+ options.forward_agent = 0;
+ break;
+ case 'A':
+ options.forward_agent = 1;
+ break;
+#ifdef AFS
+ case 'k':
+ options.kerberos_tgt_passing = 0;
+ options.afs_token_passing = 0;
+ break;
+#endif
+ case 'i':
+ if (stat(optarg, &st) < 0) {
+ 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);
+ 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)
+ force_tty_flag = 1;
+ tty_flag = 1;
+ break;
+ case 'v':
+ if (0 == debug_flag) {
+ debug_flag = 1;
+ options.log_level = SYSLOG_LEVEL_DEBUG1;
+ } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
+ options.log_level++;
+ break;
+ } else
+ fatal("Too high debugging level.");
+ /* 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());
+ if (opt == 'V')
+ exit(0);
+ break;
+ case 'q':
+ options.log_level = SYSLOG_LEVEL_QUIET;
+ break;
+ case 'e':
+ if (optarg[0] == '^' && optarg[2] == 0 &&
+ (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 = SSH_ESCAPECHAR_NONE;
+ else {
+ fprintf(stderr, "Bad escape character '%s'.\n",
+ optarg);
+ exit(1);
+ }
+ break;
+ case 'c':
+ if (ciphers_valid(optarg)) {
+ /* SSH2 only */
+ options.ciphers = xstrdup(optarg);
+ options.cipher = SSH_CIPHER_ILLEGAL;
+ } else {
+ /* SSH1 only */
+ options.cipher = cipher_number(optarg);
+ if (options.cipher == -1) {
+ fprintf(stderr,
+ "Unknown cipher type '%s'\n",
+ optarg);
+ exit(1);
+ }
+ 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 = 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, "%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 */
+ }
+ 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 '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, "socks4", 0);
+ break;
+
+ case 'C':
+ options.compression = 1;
+ break;
+ case 'N':
+ no_shell_flag = 1;
+ no_tty_flag = 1;
+ break;
+ case 'T':
+ no_tty_flag = 1;
+ break;
+ case 'o':
+ dummy = 1;
+ 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);
+
+ /*
+ * Save the command to execute on the remote host in a buffer. There
+ * 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 (!ac) {
+ /* No command specified - execute shell on a tty. */
+ tty_flag = 1;
+ if (subsystem_flag) {
+ fprintf(stderr,
+ "You must specify a subsystem to invoke.\n");
+ usage();
+ }
+ } else {
+ /* 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]));
+ }
+ }
+
+ /* Cannot fork to background if no command. */
+ if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
+ fatal("Cannot fork into background without a command to execute.");
+
+ /* Allocate a tty by default if no command specified. */
+ 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)) && !force_tty_flag) {
+ if (tty_flag)
+ log("Pseudo-terminal will not be allocated because stdin is not a terminal.");
+ tty_flag = 0;
+ }
+
+ /*
+ * 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 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, 1);
+
+ seed_rng();
+
+ if (options.user == NULL)
+ options.user = xstrdup(pw->pw_name);
+
+ if (options.hostname != NULL)
+ host = options.hostname;
+
+ /* Find canonic host name. */
+ if (strchr(host, '.') == 0) {
+ struct addrinfo hints;
+ struct addrinfo *ai = NULL;
+ int errgai;
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = IPv4or6;
+ hints.ai_flags = AI_CANONNAME;
+ hints.ai_socktype = SOCK_STREAM;
+ errgai = getaddrinfo(host, NULL, &hints, &ai);
+ if (errgai == 0) {
+ if (ai->ai_canonname != NULL)
+ host = xstrdup(ai->ai_canonname);
+ freeaddrinfo(ai);
+ }
+ }
+
+ /* 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;
+ }
+ /* Open a connection to the remote host. */
+
+ if (ssh_connect(host, &hostaddr, options.port, IPv4or6,
+ 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(1);
+
+ /*
+ * 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;
+ 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));
+
+ PRIV_START;
+ 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);
+ PRIV_END;
+
+ 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
+ * longer need them. Also, extra privileges could make it very hard
+ * to read identity files and other non-world-readable files from the
+ * 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);
+
+ /*
+ * Now that we are back to our own permissions, create ~/.ssh
+ * 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);
+
+ /* 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 =
+ 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);
+
+ signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
+
+ /* 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;
+}
+
+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, "%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 %511s %511s", proto, data) == 2)
+ got_data = 1;
+ if (f)
+ pclose(f);
+ }
+ /*
+ * 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.
+ */
+ 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;
+ }
+ }
+}
+
+static 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_setup_local_fwd_listener(
+ 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);
+ }
+}
+
+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)
+ options.forward_agent = 0;
+ else
+ ssh_close_authentication_socket(authfd);
+ }
+}
+
+static int
+ssh_session(void)
+{
+ int type;
+ int interactive = 0;
+ int have_tty = 0;
+ struct winsize ws;
+ char *cp;
+
+ /* Enable compression if requested. */
+ if (options.compression) {
+ debug("Requesting compression at level %d.", options.compression_level);
+
+ if (options.compression_level < 1 || options.compression_level > 9)
+ fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
+
+ /* Send the request. */
+ packet_start(SSH_CMSG_REQUEST_COMPRESSION);
+ packet_put_int(options.compression_level);
+ packet_send();
+ packet_write_wait();
+ type = packet_read();
+ if (type == SSH_SMSG_SUCCESS)
+ packet_start_compression(options.compression_level);
+ else if (type == SSH_SMSG_FAILURE)
+ log("Warning: Remote host refused compression.");
+ else
+ packet_disconnect("Protocol error waiting for compression response.");
+ }
+ /* Allocate a pseudo tty if appropriate. */
+ if (tty_flag) {
+ debug("Requesting pty.");
+
+ /* Start the packet. */
+ packet_start(SSH_CMSG_REQUEST_PTY);
+
+ /* Store TERM in the packet. There is no limit on the
+ length of the string. */
+ cp = getenv("TERM");
+ if (!cp)
+ cp = "";
+ packet_put_cstring(cp);
+
+ /* 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);
+
+ /* Store tty modes in the packet. */
+ 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();
+ if (type == SSH_SMSG_SUCCESS) {
+ interactive = 1;
+ have_tty = 1;
+ } else if (type == SSH_SMSG_FAILURE)
+ log("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) {
+ char *proto, *data;
+ /* Get reasonable local authentication information. */
+ 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();
+ if (type == SSH_SMSG_SUCCESS) {
+ interactive = 1;
+ } else if (type == SSH_SMSG_FAILURE) {
+ log("Warning: Remote host denied X11 forwarding.");
+ } else {
+ packet_disconnect("Protocol error waiting for X11 forwarding");
+ }
+ }
+ /* Tell the packet module whether this is an interactive session. */
+ packet_set_interactive(interactive);
+
+ /* Request authentication agent forwarding if appropriate. */
+ check_agent_present();
+
+ if (options.forward_agent) {
+ debug("Requesting authentication agent forwarding.");
+ auth_request_forwarding();
+
+ /* Read response from the server. */
+ type = packet_read();
+ packet_check_eom();
+ if (type != SSH_SMSG_SUCCESS)
+ log("Warning: Remote host denied authentication agent forwarding.");
+ }
+
+ /* Initiate port forwardings. */
+ 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));
+
+ /*
+ * If a command was specified on the command line, execute the
+ * command now. Otherwise request the server to start a shell.
+ */
+ if (buffer_len(&command) > 0) {
+ int len = buffer_len(&command);
+ if (len > 900)
+ len = 900;
+ 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();
+ packet_write_wait();
+ } else {
+ debug("Requesting shell.");
+ packet_start(SSH_CMSG_EXEC_SHELL);
+ packet_send();
+ packet_write_wait();
+ }
+
+ /* Enter the interactive session. */
+ return client_loop(have_tty, tty_flag ?
+ options.escape_char : SSH_ESCAPECHAR_NONE, 0);
+}
+
+static void
+client_subsystem_reply(int type, u_int32_t seq, void *ctxt)
+{
+ int id, len;
+
+ id = packet_get_int();
+ len = buffer_len(&command);
+ if (len > 900)
+ len = 900;
+ packet_check_eom();
+ if (type == SSH2_MSG_CHANNEL_FAILURE)
+ fatal("Request for subsystem '%.*s' failed on channel %d",
+ len, (u_char *)buffer_ptr(&command), id);
+}
+
+void
+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("ssh_session2_setup: id %d", id);
+
+ 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));
+
+ 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 (options.forward_x11 &&
+ getenv("DISPLAY") != NULL) {
+ char *proto, *data;
+ /* Get reasonable local authentication information. */
+ 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);
+ 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;
+ 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();
+ }
+
+ packet_set_interactive(interactive);
+}
+
+/* open new channel for a session */
+static int
+ssh_session2_open(void)
+{
+ Channel *c;
+ int window, packetmax, in, out, err;
+
+ if (stdin_null_flag) {
+ in = open(_PATH_DEVNULL, O_RDONLY);
+ } else {
+ in = dup(STDIN_FILENO);
+ }
+ out = dup(STDOUT_FILENO);
+ err = dup(STDERR_FILENO);
+
+ if (in < 0 || out < 0 || err < 0)
+ fatal("dup() in/out/err failed");
+
+ /* enable nonblocking unless tty */
+ if (!isatty(in))
+ set_nonblock(in);
+ if (!isatty(out))
+ set_nonblock(out);
+ if (!isatty(err))
+ set_nonblock(err);
+
+ window = CHAN_SES_WINDOW_DEFAULT;
+ packetmax = CHAN_SES_PACKET_DEFAULT;
+ 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);
+
+ 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);
+
+ return c->self;
+}
+
+static int
+ssh_session2(void)
+{
+ int id = -1;
+
+ /* 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);
+ }
+#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;
+ }
+}
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