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-rw-r--r--crypto/openssh/ssh.c1656
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diff --git a/crypto/openssh/ssh.c b/crypto/openssh/ssh.c
new file mode 100644
index 0000000..7fdae3a
--- /dev/null
+++ b/crypto/openssh/ssh.c
@@ -0,0 +1,1656 @@
+/* $OpenBSD: ssh.c,v 1.364 2011/08/02 23:15:03 djm Exp $ */
+/* $FreeBSD$ */
+/*
+ * 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, 2003 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("$FreeBSD$");
+
+#include <sys/types.h>
+#ifdef HAVE_SYS_STAT_H
+# include <sys/stat.h>
+#endif
+#include <sys/resource.h>
+#include <sys/ioctl.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <netdb.h>
+#ifdef HAVE_PATHS_H
+#include <paths.h>
+#endif
+#include <pwd.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <openssl/evp.h>
+#include <openssl/err.h>
+#include "openbsd-compat/openssl-compat.h"
+#include "openbsd-compat/sys-queue.h"
+
+#include "xmalloc.h"
+#include "ssh.h"
+#include "ssh1.h"
+#include "ssh2.h"
+#include "canohost.h"
+#include "compat.h"
+#include "cipher.h"
+#include "packet.h"
+#include "buffer.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 "misc.h"
+#include "kex.h"
+#include "mac.h"
+#include "sshpty.h"
+#include "match.h"
+#include "msg.h"
+#include "uidswap.h"
+#include "roaming.h"
+#include "version.h"
+
+#ifdef ENABLE_PKCS11
+#include "ssh-pkcs11.h"
+#endif
+
+extern char *__progname;
+
+/* Saves a copy of argv for setproctitle emulation */
+#ifndef HAVE_SETPROCTITLE
+static char **saved_av;
+#endif
+
+/* Flag indicating whether debug mode is on. May be set on the command line. */
+int debug_flag = 0;
+
+/* Flag indicating whether a tty should be requested */
+int 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 the current process should be backgrounded and
+ * a new slave launched in the foreground for ControlPersist.
+ */
+int need_controlpersist_detach = 0;
+
+/* Copies of flags for ControlPersist foreground slave */
+int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
+
+/*
+ * 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;
+
+/* forward stdio to remote host and port */
+char *stdio_forward_host = NULL;
+int stdio_forward_port = 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 remote_forward_confirms_received = 0;
+
+/* mux.c */
+extern int muxserver_sock;
+extern u_int muxclient_command;
+
+/* Prints a help message to the user. This function never returns. */
+
+static void
+usage(void)
+{
+ fprintf(stderr,
+"usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
+" [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
+" [-I pkcs11] [-i identity_file]\n"
+" [-L [bind_address:]port:host:hostport]\n"
+" [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
+" [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
+" [-W host:port] [-w local_tun[:remote_tun]]\n"
+" [user@]hostname [command]\n"
+ );
+ exit(255);
+}
+
+static int ssh_session(void);
+static int ssh_session2(void);
+static void load_public_identity_files(void);
+static void main_sigchld_handler(int);
+
+/* from muxclient.c */
+void muxclient(const char *);
+void muxserver_listen(void);
+
+/* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
+static void
+tilde_expand_paths(char **paths, u_int num_paths)
+{
+ u_int i;
+ char *cp;
+
+ for (i = 0; i < num_paths; i++) {
+ cp = tilde_expand_filename(paths[i], original_real_uid);
+ xfree(paths[i]);
+ paths[i] = cp;
+ }
+}
+
+/*
+ * Main program for the ssh client.
+ */
+int
+main(int ac, char **av)
+{
+ int i, r, opt, exit_status, use_syslog;
+ char *p, *cp, *line, *argv0, buf[MAXPATHLEN], *host_arg;
+ char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
+ struct stat st;
+ struct passwd *pw;
+ int dummy, timeout_ms;
+ extern int optind, optreset;
+ extern char *optarg;
+
+ struct servent *sp;
+ Forward fwd;
+
+ /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
+ sanitise_stdfd();
+
+ __progname = ssh_get_progname(av[0]);
+
+#ifndef HAVE_SETPROCTITLE
+ /* Prepare for later setproctitle emulation */
+ /* Save argv so it isn't clobbered by setproctitle() emulation */
+ saved_av = xcalloc(ac + 1, sizeof(*saved_av));
+ for (i = 0; i < ac; i++)
+ saved_av[i] = xstrdup(av[i]);
+ saved_av[i] = NULL;
+ compat_init_setproctitle(ac, av);
+ av = saved_av;
+#endif
+
+ /*
+ * Discard other fds that are hanging around. These can cause problem
+ * with backgrounded ssh processes started by ControlPersist.
+ */
+ closefrom(STDERR_FILENO + 1);
+
+ /*
+ * 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();
+
+ /*
+ * 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;
+
+#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) {
+ logit("You don't exist, go away!");
+ exit(255);
+ }
+ /* Take a copy of the returned structure. */
+ pw = pwcopy(pw);
+
+ /*
+ * 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;
+ use_syslog = 0;
+ argv0 = av[0];
+
+ again:
+ while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
+ "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) {
+ switch (opt) {
+ case '1':
+ options.protocol = SSH_PROTO_1;
+ break;
+ case '2':
+ options.protocol = SSH_PROTO_2;
+ break;
+ case '4':
+ options.address_family = AF_INET;
+ break;
+ case '6':
+ options.address_family = 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 'y':
+ use_syslog = 1;
+ break;
+ case 'Y':
+ options.forward_x11 = 1;
+ options.forward_x11_trusted = 1;
+ break;
+ case 'g':
+ options.gateway_ports = 1;
+ break;
+ case 'O':
+ if (stdio_forward_host != NULL)
+ fatal("Cannot specify multiplexing "
+ "command with -W");
+ else if (muxclient_command != 0)
+ fatal("Multiplexing command already specified");
+ if (strcmp(optarg, "check") == 0)
+ muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
+ else if (strcmp(optarg, "forward") == 0)
+ muxclient_command = SSHMUX_COMMAND_FORWARD;
+ else if (strcmp(optarg, "exit") == 0)
+ muxclient_command = SSHMUX_COMMAND_TERMINATE;
+ else if (strcmp(optarg, "stop") == 0)
+ muxclient_command = SSHMUX_COMMAND_STOP;
+ else
+ fatal("Invalid multiplex command.");
+ break;
+ case 'P': /* deprecated */
+ options.use_privileged_port = 0;
+ break;
+ case 'a':
+ options.forward_agent = 0;
+ break;
+ case 'A':
+ options.forward_agent = 1;
+ break;
+ case 'k':
+ options.gss_deleg_creds = 0;
+ break;
+ case 'K':
+ options.gss_authentication = 1;
+ options.gss_deleg_creds = 1;
+ break;
+ case 'i':
+ if (stat(optarg, &st) < 0) {
+ fprintf(stderr, "Warning: Identity file %s "
+ "not accessible: %s.\n", optarg,
+ strerror(errno));
+ 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 ENABLE_PKCS11
+ options.pkcs11_provider = xstrdup(optarg);
+#else
+ fprintf(stderr, "no support for PKCS#11.\n");
+#endif
+ break;
+ case 't':
+ if (options.request_tty == REQUEST_TTY_YES)
+ options.request_tty = REQUEST_TTY_FORCE;
+ else
+ options.request_tty = REQUEST_TTY_YES;
+ break;
+ case 'v':
+ if (debug_flag == 0) {
+ debug_flag = 1;
+ options.log_level = SYSLOG_LEVEL_DEBUG1;
+ } else {
+ if (options.log_level < SYSLOG_LEVEL_DEBUG3)
+ options.log_level++;
+ break;
+ }
+ /* FALLTHROUGH */
+ case 'V':
+ fprintf(stderr, "%s, %s\n",
+ SSH_RELEASE, SSLeay_version(SSLEAY_VERSION));
+ if (opt == 'V')
+ exit(0);
+ break;
+ case 'w':
+ if (options.tun_open == -1)
+ options.tun_open = SSH_TUNMODE_DEFAULT;
+ options.tun_local = a2tun(optarg, &options.tun_remote);
+ if (options.tun_local == SSH_TUNID_ERR) {
+ fprintf(stderr,
+ "Bad tun device '%s'\n", optarg);
+ exit(255);
+ }
+ break;
+ case 'W':
+ if (stdio_forward_host != NULL)
+ fatal("stdio forward already specified");
+ if (muxclient_command != 0)
+ fatal("Cannot specify stdio forward with -O");
+ if (parse_forward(&fwd, optarg, 1, 0)) {
+ stdio_forward_host = fwd.listen_host;
+ stdio_forward_port = fwd.listen_port;
+ xfree(fwd.connect_host);
+ } else {
+ fprintf(stderr,
+ "Bad stdio forwarding specification '%s'\n",
+ optarg);
+ exit(255);
+ }
+ options.request_tty = REQUEST_TTY_NO;
+ no_shell_flag = 1;
+ options.clear_forwardings = 1;
+ options.exit_on_forward_failure = 1;
+ 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(255);
+ }
+ break;
+ case 'c':
+ if (ciphers_valid(optarg)) {
+ /* SSH2 only */
+ options.ciphers = xstrdup(optarg);
+ options.cipher = SSH_CIPHER_INVALID;
+ } else {
+ /* SSH1 only */
+ options.cipher = cipher_number(optarg);
+ if (options.cipher == -1) {
+ fprintf(stderr,
+ "Unknown cipher type '%s'\n",
+ optarg);
+ exit(255);
+ }
+ 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(255);
+ }
+ break;
+ case 'M':
+ if (options.control_master == SSHCTL_MASTER_YES)
+ options.control_master = SSHCTL_MASTER_ASK;
+ else
+ options.control_master = SSHCTL_MASTER_YES;
+ break;
+ case 'p':
+ options.port = a2port(optarg);
+ if (options.port <= 0) {
+ fprintf(stderr, "Bad port '%s'\n", optarg);
+ exit(255);
+ }
+ break;
+ case 'l':
+ options.user = optarg;
+ break;
+
+ case 'L':
+ if (parse_forward(&fwd, optarg, 0, 0))
+ add_local_forward(&options, &fwd);
+ else {
+ fprintf(stderr,
+ "Bad local forwarding specification '%s'\n",
+ optarg);
+ exit(255);
+ }
+ break;
+
+ case 'R':
+ if (parse_forward(&fwd, optarg, 0, 1)) {
+ add_remote_forward(&options, &fwd);
+ } else {
+ fprintf(stderr,
+ "Bad remote forwarding specification "
+ "'%s'\n", optarg);
+ exit(255);
+ }
+ break;
+
+ case 'D':
+ if (parse_forward(&fwd, optarg, 1, 0)) {
+ add_local_forward(&options, &fwd);
+ } else {
+ fprintf(stderr,
+ "Bad dynamic forwarding specification "
+ "'%s'\n", optarg);
+ exit(255);
+ }
+ break;
+
+ case 'C':
+ options.compression = 1;
+ break;
+ case 'N':
+ no_shell_flag = 1;
+ options.request_tty = REQUEST_TTY_NO;
+ break;
+ case 'T':
+ options.request_tty = REQUEST_TTY_NO;
+#ifdef NONE_CIPHER_ENABLED
+ /*
+ * Ensure that the user does not try to backdoor a
+ * NONE cipher switch on an interactive session by
+ * explicitly disabling it if the user asks for a
+ * session without a tty.
+ */
+ options.none_switch = 0;
+#endif
+ break;
+ case 'o':
+ dummy = 1;
+ line = xstrdup(optarg);
+ if (process_config_line(&options, host ? host : "",
+ line, "command-line", 0, &dummy) != 0)
+ exit(255);
+ xfree(line);
+ break;
+ 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;
+ case 'F':
+ config = optarg;
+ break;
+ default:
+ usage();
+ }
+ }
+
+ ac -= optind;
+ av += optind;
+
+ if (ac > 0 && !host) {
+ if (strrchr(*av, '@')) {
+ p = xstrdup(*av);
+ cp = strrchr(p, '@');
+ if (cp == NULL || cp == p)
+ usage();
+ options.user = p;
+ *cp = '\0';
+ host = ++cp;
+ } else
+ host = *av;
+ if (ac > 1) {
+ optind = optreset = 1;
+ goto again;
+ }
+ ac--, av++;
+ }
+
+ /* Check that we got a host name. */
+ if (!host)
+ usage();
+
+ OpenSSL_add_all_algorithms();
+ ERR_load_crypto_strings();
+
+ /* Initialize the command to execute on remote host. */
+ buffer_init(&command);
+
+ if (options.request_tty == REQUEST_TTY_YES ||
+ options.request_tty == REQUEST_TTY_FORCE)
+ tty_flag = 1;
+
+ /*
+ * 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 = options.request_tty != REQUEST_TTY_NO;
+ 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 = options.request_tty != REQUEST_TTY_NO;
+
+ /* Force no tty */
+ if (options.request_tty == REQUEST_TTY_NO || muxclient_command != 0)
+ tty_flag = 0;
+ /* Do not allocate a tty if stdin is not a tty. */
+ if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
+ options.request_tty != REQUEST_TTY_FORCE) {
+ if (tty_flag)
+ logit("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(argv0,
+ options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
+ SYSLOG_FACILITY_USER, !use_syslog);
+
+ /*
+ * 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, 0))
+ fatal("Can't open user config file %.100s: "
+ "%.100s", config, strerror(errno));
+ } else {
+ r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
+ _PATH_SSH_USER_CONFFILE);
+ if (r > 0 && (size_t)r < sizeof(buf))
+ (void)read_config_file(buf, host, &options, 1);
+
+ /* Read systemwide configuration file after user config. */
+ (void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
+ &options, 0);
+ }
+
+ /* Fill configuration defaults. */
+ fill_default_options(&options);
+
+ channel_set_af(options.address_family);
+
+ /* reinit */
+ log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
+
+ seed_rng();
+
+ if (options.user == NULL)
+ options.user = xstrdup(pw->pw_name);
+
+ /* Get default port if port has not been set. */
+ if (options.port == 0) {
+ sp = getservbyname(SSH_SERVICE_NAME, "tcp");
+ options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
+ }
+
+ /* preserve host name given on command line for %n expansion */
+ host_arg = host;
+ if (options.hostname != NULL) {
+ host = percent_expand(options.hostname,
+ "h", host, (char *)NULL);
+ }
+
+ if (gethostname(thishost, sizeof(thishost)) == -1)
+ fatal("gethostname: %s", strerror(errno));
+ strlcpy(shorthost, thishost, sizeof(shorthost));
+ shorthost[strcspn(thishost, ".")] = '\0';
+ snprintf(portstr, sizeof(portstr), "%d", options.port);
+
+ if (options.local_command != NULL) {
+ debug3("expanding LocalCommand: %s", options.local_command);
+ cp = options.local_command;
+ options.local_command = percent_expand(cp, "d", pw->pw_dir,
+ "h", host, "l", thishost, "n", host_arg, "r", options.user,
+ "p", portstr, "u", pw->pw_name, "L", shorthost,
+ (char *)NULL);
+ debug3("expanded LocalCommand: %s", options.local_command);
+ xfree(cp);
+ }
+
+ /* 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 = options.address_family;
+ 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);
+ }
+ }
+
+ /* force lowercase for hostkey matching */
+ if (options.host_key_alias != NULL) {
+ for (p = options.host_key_alias; *p; p++)
+ if (isupper(*p))
+ *p = (char)tolower(*p);
+ }
+
+ if (options.proxy_command != NULL &&
+ strcmp(options.proxy_command, "none") == 0) {
+ xfree(options.proxy_command);
+ options.proxy_command = NULL;
+ }
+ if (options.control_path != NULL &&
+ strcmp(options.control_path, "none") == 0) {
+ xfree(options.control_path);
+ options.control_path = NULL;
+ }
+
+ if (options.control_path != NULL) {
+ cp = tilde_expand_filename(options.control_path,
+ original_real_uid);
+ xfree(options.control_path);
+ options.control_path = percent_expand(cp, "h", host,
+ "l", thishost, "n", host_arg, "r", options.user,
+ "p", portstr, "u", pw->pw_name, "L", shorthost,
+ (char *)NULL);
+ xfree(cp);
+ }
+ if (muxclient_command != 0 && options.control_path == NULL)
+ fatal("No ControlPath specified for \"-O\" command");
+ if (options.control_path != NULL)
+ muxclient(options.control_path);
+
+ timeout_ms = options.connection_timeout * 1000;
+
+ /* Open a connection to the remote host. */
+ if (ssh_connect(host, &hostaddr, options.port,
+ options.address_family, options.connection_attempts, &timeout_ms,
+ options.tcp_keep_alive,
+#ifdef HAVE_CYGWIN
+ options.use_privileged_port,
+#else
+ original_effective_uid == 0 && options.use_privileged_port,
+#endif
+ options.proxy_command) != 0)
+ exit(255);
+
+ if (timeout_ms > 0)
+ debug3("timeout: %d ms remain after connect", timeout_ms);
+
+ /*
+ * 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 = 7;
+ sensitive_data.keys = xcalloc(sensitive_data.nkeys,
+ sizeof(Key));
+ for (i = 0; i < sensitive_data.nkeys; i++)
+ sensitive_data.keys[i] = NULL;
+
+ PRIV_START;
+ sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
+ _PATH_HOST_KEY_FILE, "", NULL, NULL);
+ sensitive_data.keys[1] = key_load_private_cert(KEY_DSA,
+ _PATH_HOST_DSA_KEY_FILE, "", NULL);
+#ifdef OPENSSL_HAS_ECC
+ sensitive_data.keys[2] = key_load_private_cert(KEY_ECDSA,
+ _PATH_HOST_ECDSA_KEY_FILE, "", NULL);
+#endif
+ sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
+ _PATH_HOST_RSA_KEY_FILE, "", NULL);
+ sensitive_data.keys[4] = key_load_private_type(KEY_DSA,
+ _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
+#ifdef OPENSSL_HAS_ECC
+ sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
+ _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
+#endif
+ sensitive_data.keys[6] = key_load_private_type(KEY_RSA,
+ _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
+ PRIV_END;
+
+ if (options.hostbased_authentication == 1 &&
+ sensitive_data.keys[0] == NULL &&
+ sensitive_data.keys[4] == NULL &&
+ sensitive_data.keys[5] == NULL &&
+ sensitive_data.keys[6] == NULL) {
+ sensitive_data.keys[1] = key_load_cert(
+ _PATH_HOST_DSA_KEY_FILE);
+#ifdef OPENSSL_HAS_ECC
+ sensitive_data.keys[2] = key_load_cert(
+ _PATH_HOST_ECDSA_KEY_FILE);
+#endif
+ sensitive_data.keys[3] = key_load_cert(
+ _PATH_HOST_RSA_KEY_FILE);
+ sensitive_data.keys[4] = key_load_public(
+ _PATH_HOST_DSA_KEY_FILE, NULL);
+#ifdef OPENSSL_HAS_ECC
+ sensitive_data.keys[5] = key_load_public(
+ _PATH_HOST_ECDSA_KEY_FILE, NULL);
+#endif
+ sensitive_data.keys[6] = 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.
+ */
+ if (original_effective_uid == 0) {
+ PRIV_START;
+ permanently_set_uid(pw);
+ }
+
+ /*
+ * Now that we are back to our own permissions, create ~/.ssh
+ * directory if it doesn't already exist.
+ */
+ r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
+ strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
+ if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) {
+#ifdef WITH_SELINUX
+ ssh_selinux_setfscreatecon(buf);
+#endif
+ if (mkdir(buf, 0700) < 0)
+ error("Could not create directory '%.200s'.", buf);
+#ifdef WITH_SELINUX
+ ssh_selinux_setfscreatecon(NULL);
+#endif
+ }
+ /* load options.identity_files */
+ load_public_identity_files();
+
+ /* Expand ~ in known host file names. */
+ tilde_expand_paths(options.system_hostfiles,
+ options.num_system_hostfiles);
+ tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
+
+ signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
+ signal(SIGCHLD, main_sigchld_handler);
+
+ /* Log into the remote system. Never returns if the login fails. */
+ ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
+ options.port, pw, timeout_ms);
+
+ if (packet_connection_is_on_socket()) {
+ verbose("Authenticated to %s ([%s]:%d).", host,
+ get_remote_ipaddr(), get_remote_port());
+ } else {
+ verbose("Authenticated to %s (via proxy).", host);
+ }
+
+ /* 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();
+
+ if (options.control_path != NULL && muxserver_sock != -1)
+ unlink(options.control_path);
+
+ /* Kill ProxyCommand if it is running. */
+ ssh_kill_proxy_command();
+
+ return exit_status;
+}
+
+static void
+control_persist_detach(void)
+{
+ pid_t pid;
+ int devnull;
+
+ debug("%s: backgrounding master process", __func__);
+
+ /*
+ * master (current process) into the background, and make the
+ * foreground process a client of the backgrounded master.
+ */
+ switch ((pid = fork())) {
+ case -1:
+ fatal("%s: fork: %s", __func__, strerror(errno));
+ case 0:
+ /* Child: master process continues mainloop */
+ break;
+ default:
+ /* Parent: set up mux slave to connect to backgrounded master */
+ debug2("%s: background process is %ld", __func__, (long)pid);
+ stdin_null_flag = ostdin_null_flag;
+ options.request_tty = orequest_tty;
+ tty_flag = otty_flag;
+ close(muxserver_sock);
+ muxserver_sock = -1;
+ options.control_master = SSHCTL_MASTER_NO;
+ muxclient(options.control_path);
+ /* muxclient() doesn't return on success. */
+ fatal("Failed to connect to new control master");
+ }
+ if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
+ error("%s: open(\"/dev/null\"): %s", __func__,
+ strerror(errno));
+ } else {
+ if (dup2(devnull, STDIN_FILENO) == -1 ||
+ dup2(devnull, STDOUT_FILENO) == -1)
+ error("%s: dup2: %s", __func__, strerror(errno));
+ if (devnull > STDERR_FILENO)
+ close(devnull);
+ }
+ setproctitle("%s [mux]", options.control_path);
+}
+
+/* Do fork() after authentication. Used by "ssh -f" */
+static void
+fork_postauth(void)
+{
+ if (need_controlpersist_detach)
+ control_persist_detach();
+ debug("forking to background");
+ fork_after_authentication_flag = 0;
+ if (daemon(1, 1) < 0)
+ fatal("daemon() failed: %.200s", strerror(errno));
+}
+
+/* Callback for remote forward global requests */
+static void
+ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
+{
+ Forward *rfwd = (Forward *)ctxt;
+
+ /* XXX verbose() on failure? */
+ debug("remote forward %s for: listen %d, connect %s:%d",
+ type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
+ rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
+ if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) {
+ rfwd->allocated_port = packet_get_int();
+ logit("Allocated port %u for remote forward to %s:%d",
+ rfwd->allocated_port,
+ rfwd->connect_host, rfwd->connect_port);
+ }
+
+ if (type == SSH2_MSG_REQUEST_FAILURE) {
+ if (options.exit_on_forward_failure)
+ fatal("Error: remote port forwarding failed for "
+ "listen port %d", rfwd->listen_port);
+ else
+ logit("Warning: remote port forwarding failed for "
+ "listen port %d", rfwd->listen_port);
+ }
+ if (++remote_forward_confirms_received == options.num_remote_forwards) {
+ debug("All remote forwarding requests processed");
+ if (fork_after_authentication_flag)
+ fork_postauth();
+ }
+}
+
+static void
+client_cleanup_stdio_fwd(int id, void *arg)
+{
+ debug("stdio forwarding: done");
+ cleanup_exit(0);
+}
+
+static int
+client_setup_stdio_fwd(const char *host_to_connect, u_short port_to_connect)
+{
+ Channel *c;
+ int in, out;
+
+ debug3("client_setup_stdio_fwd %s:%d", host_to_connect,
+ port_to_connect);
+
+ in = dup(STDIN_FILENO);
+ out = dup(STDOUT_FILENO);
+ if (in < 0 || out < 0)
+ fatal("channel_connect_stdio_fwd: dup() in/out failed");
+
+ if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect,
+ in, out)) == NULL)
+ return 0;
+ channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
+ return 1;
+}
+
+static void
+ssh_init_forwarding(void)
+{
+ int success = 0;
+ int i;
+
+ if (stdio_forward_host != NULL) {
+ if (!compat20) {
+ fatal("stdio forwarding require Protocol 2");
+ }
+ if (!client_setup_stdio_fwd(stdio_forward_host,
+ stdio_forward_port))
+ fatal("Failed to connect in stdio forward mode.");
+ }
+
+ /* Initiate local TCP/IP port forwardings. */
+ for (i = 0; i < options.num_local_forwards; i++) {
+ debug("Local connections to %.200s:%d forwarded to remote "
+ "address %.200s:%d",
+ (options.local_forwards[i].listen_host == NULL) ?
+ (options.gateway_ports ? "*" : "LOCALHOST") :
+ options.local_forwards[i].listen_host,
+ options.local_forwards[i].listen_port,
+ options.local_forwards[i].connect_host,
+ options.local_forwards[i].connect_port);
+ success += channel_setup_local_fwd_listener(
+ options.local_forwards[i].listen_host,
+ options.local_forwards[i].listen_port,
+ options.local_forwards[i].connect_host,
+ options.local_forwards[i].connect_port,
+ options.gateway_ports);
+ }
+ if (i > 0 && success != i && options.exit_on_forward_failure)
+ fatal("Could not request local forwarding.");
+ 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("Remote connections from %.200s:%d forwarded to "
+ "local address %.200s:%d",
+ (options.remote_forwards[i].listen_host == NULL) ?
+ "LOCALHOST" : options.remote_forwards[i].listen_host,
+ options.remote_forwards[i].listen_port,
+ options.remote_forwards[i].connect_host,
+ options.remote_forwards[i].connect_port);
+ if (channel_request_remote_forwarding(
+ options.remote_forwards[i].listen_host,
+ options.remote_forwards[i].listen_port,
+ options.remote_forwards[i].connect_host,
+ options.remote_forwards[i].connect_port) < 0) {
+ if (options.exit_on_forward_failure)
+ fatal("Could not request remote forwarding.");
+ else
+ logit("Warning: Could not request remote "
+ "forwarding.");
+ }
+ client_register_global_confirm(ssh_confirm_remote_forward,
+ &options.remote_forwards[i]);
+ }
+
+ /* Initiate tunnel forwarding. */
+ if (options.tun_open != SSH_TUNMODE_NO) {
+ if (client_request_tun_fwd(options.tun_open,
+ options.tun_local, options.tun_remote) == -1) {
+ if (options.exit_on_forward_failure)
+ fatal("Could not request tunnel forwarding.");
+ else
+ error("Could not request tunnel forwarding.");
+ }
+ }
+}
+
+static void
+check_agent_present(void)
+{
+ if (options.forward_agent) {
+ /* Clear agent forwarding if we don't have an agent. */
+ if (!ssh_agent_present())
+ options.forward_agent = 0;
+ }
+}
+
+static int
+ssh_session(void)
+{
+ int type;
+ int interactive = 0;
+ int have_tty = 0;
+ struct winsize ws;
+ char *cp;
+ const char *display;
+
+ /* 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)
+ logit("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((u_int)ws.ws_row);
+ packet_put_int((u_int)ws.ws_col);
+ packet_put_int((u_int)ws.ws_xpixel);
+ packet_put_int((u_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)
+ logit("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. */
+ display = getenv("DISPLAY");
+ if (options.forward_x11 && display != NULL) {
+ char *proto, *data;
+ /* Get reasonable local authentication information. */
+ client_x11_get_proto(display, options.xauth_location,
+ options.forward_x11_trusted,
+ options.forward_x11_timeout,
+ &proto, &data);
+ /* Request forwarding with authentication spoofing. */
+ debug("Requesting X11 forwarding with authentication "
+ "spoofing.");
+ x11_request_forwarding_with_spoofing(0, display, proto,
+ data, 0);
+ /* Read response from the server. */
+ type = packet_read();
+ if (type == SSH_SMSG_SUCCESS) {
+ interactive = 1;
+ } else if (type == SSH_SMSG_FAILURE) {
+ logit("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,
+ options.ip_qos_interactive, options.ip_qos_bulk);
+
+ /* 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)
+ logit("Warning: Remote host denied authentication agent forwarding.");
+ }
+
+ /* Initiate port forwardings. */
+ ssh_init_forwarding();
+
+ /* Execute a local command */
+ if (options.local_command != NULL &&
+ options.permit_local_command)
+ ssh_local_cmd(options.local_command);
+
+ /*
+ * If requested and we are not interested in replies to remote
+ * forwarding requests, then let ssh continue in the background.
+ */
+ if (fork_after_authentication_flag) {
+ if (options.exit_on_forward_failure &&
+ options.num_remote_forwards > 0) {
+ debug("deferring postauth fork until remote forward "
+ "confirmation received");
+ } else
+ fork_postauth();
+ }
+
+ /*
+ * 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);
+}
+
+/* request pty/x11/agent/tcpfwd/shell for channel */
+static void
+ssh_session2_setup(int id, int success, void *arg)
+{
+ extern char **environ;
+ const char *display;
+ int interactive = tty_flag;
+
+ if (!success)
+ return; /* No need for error message, channels code sens one */
+
+ display = getenv("DISPLAY");
+ if (options.forward_x11 && display != NULL) {
+ char *proto, *data;
+ /* Get reasonable local authentication information. */
+ client_x11_get_proto(display, options.xauth_location,
+ options.forward_x11_trusted,
+ options.forward_x11_timeout, &proto, &data);
+ /* Request forwarding with authentication spoofing. */
+ debug("Requesting X11 forwarding with authentication "
+ "spoofing.");
+ x11_request_forwarding_with_spoofing(id, display, proto,
+ data, 1);
+ client_expect_confirm(id, "X11 forwarding", CONFIRM_WARN);
+ /* XXX exit_on_forward_failure */
+ interactive = 1;
+ }
+
+ check_agent_present();
+ if (options.forward_agent) {
+ debug("Requesting authentication agent forwarding.");
+ channel_request_start(id, "auth-agent-req@openssh.com", 0);
+ packet_send();
+ }
+
+ client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
+ NULL, fileno(stdin), &command, environ);
+}
+
+/* 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);
+
+ /*
+ * We need to check to see what to do about buffer sizes here.
+ * - In an HPN to non-HPN connection we want to limit the window size to
+ * something reasonable in case the far side has the large window bug.
+ * - In an HPN to HPN connection we want to use the max window size but
+ * allow the user to override it.
+ * - Lastly if HPN is disabled then use the ssh standard window size.
+ *
+ * We cannot just do a getsockopt() here and set the ssh window to that
+ * as in case of autotuning of socket buffers the window would get stuck
+ * at the initial buffer size, generally less than 96k. Therefore we
+ * need to set the maximum ssh window size to the maximum HPN buffer
+ * size unless the user has set TcpRcvBufPoll to no. In that case we
+ * can just set the window to the minimum of HPN buffer size and TCP
+ * receive buffer size.
+ */
+ if (tty_flag)
+ options.hpn_buffer_size = CHAN_SES_WINDOW_DEFAULT;
+ else
+ options.hpn_buffer_size = CHAN_HPN_MIN_WINDOW_DEFAULT;
+
+ if (datafellows & SSH_BUG_LARGEWINDOW) {
+ debug("HPN to Non-HPN Connection");
+ } else if (options.tcp_rcv_buf_poll <= 0) {
+ sock_get_rcvbuf(&options.hpn_buffer_size, 0);
+ debug("HPNBufferSize set to TCP RWIN: %d",
+ options.hpn_buffer_size);
+ } else if (options.tcp_rcv_buf > 0) {
+ sock_get_rcvbuf(&options.hpn_buffer_size,
+ options.tcp_rcv_buf);
+ debug("HPNBufferSize set to user TCPRcvBuf: %d",
+ options.hpn_buffer_size);
+ }
+ debug("Final hpn_buffer_size = %d", options.hpn_buffer_size);
+ channel_set_hpn(options.hpn_disabled, options.hpn_buffer_size);
+ window = options.hpn_buffer_size;
+
+ packetmax = CHAN_SES_PACKET_DEFAULT;
+ if (tty_flag) {
+ window = CHAN_SES_WINDOW_DEFAULT;
+ window >>= 1;
+ packetmax >>= 1;
+ }
+ c = channel_new(
+ "session", SSH_CHANNEL_OPENING, in, out, err,
+ window, packetmax, CHAN_EXTENDED_WRITE,
+ "client-session", /*nonblock*/0);
+ if (!options.hpn_disabled && options.tcp_rcv_buf_poll > 0) {
+ c->dynamic_window = 1;
+ debug("Enabled Dynamic Window Scaling\n");
+ }
+ debug3("ssh_session2_open: channel_new: %d", c->self);
+
+ channel_send_open(c->self);
+ if (!no_shell_flag)
+ channel_register_open_confirm(c->self,
+ ssh_session2_setup, NULL);
+
+ return c->self;
+}
+
+static int
+ssh_session2(void)
+{
+ int id = -1;
+
+ /* XXX should be pre-session */
+ ssh_init_forwarding();
+
+ /* Start listening for multiplex clients */
+ muxserver_listen();
+
+ /*
+ * If we are in control persist mode, then prepare to background
+ * ourselves and have a foreground client attach as a control
+ * slave. NB. we must save copies of the flags that we override for
+ * the backgrounding, since we defer attachment of the slave until
+ * after the connection is fully established (in particular,
+ * async rfwd replies have been received for ExitOnForwardFailure).
+ */
+ if (options.control_persist && muxserver_sock != -1) {
+ ostdin_null_flag = stdin_null_flag;
+ ono_shell_flag = no_shell_flag;
+ orequest_tty = options.request_tty;
+ otty_flag = tty_flag;
+ stdin_null_flag = 1;
+ no_shell_flag = 1;
+ tty_flag = 0;
+ if (!fork_after_authentication_flag)
+ need_controlpersist_detach = 1;
+ fork_after_authentication_flag = 1;
+ }
+
+ if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
+ id = ssh_session2_open();
+
+ /* If we don't expect to open a new session, then disallow it */
+ if (options.control_master == SSHCTL_MASTER_NO &&
+ (datafellows & SSH_NEW_OPENSSH)) {
+ debug("Requesting no-more-sessions@openssh.com");
+ packet_start(SSH2_MSG_GLOBAL_REQUEST);
+ packet_put_cstring("no-more-sessions@openssh.com");
+ packet_put_char(0);
+ packet_send();
+ }
+
+ /* Execute a local command */
+ if (options.local_command != NULL &&
+ options.permit_local_command)
+ ssh_local_cmd(options.local_command);
+
+ /*
+ * If requested and we are not interested in replies to remote
+ * forwarding requests, then let ssh continue in the background.
+ */
+ if (fork_after_authentication_flag) {
+ if (options.exit_on_forward_failure &&
+ options.num_remote_forwards > 0) {
+ debug("deferring postauth fork until remote forward "
+ "confirmation received");
+ } else
+ fork_postauth();
+ }
+
+ if (options.use_roaming)
+ request_roaming();
+
+ return client_loop(tty_flag, tty_flag ?
+ options.escape_char : SSH_ESCAPECHAR_NONE, id);
+}
+
+static void
+load_public_identity_files(void)
+{
+ char *filename, *cp, thishost[NI_MAXHOST];
+ char *pwdir = NULL, *pwname = NULL;
+ int i = 0;
+ Key *public;
+ struct passwd *pw;
+ u_int n_ids;
+ char *identity_files[SSH_MAX_IDENTITY_FILES];
+ Key *identity_keys[SSH_MAX_IDENTITY_FILES];
+#ifdef ENABLE_PKCS11
+ Key **keys;
+ int nkeys;
+#endif /* PKCS11 */
+
+ n_ids = 0;
+ bzero(identity_files, sizeof(identity_files));
+ bzero(identity_keys, sizeof(identity_keys));
+
+#ifdef ENABLE_PKCS11
+ if (options.pkcs11_provider != NULL &&
+ options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
+ (pkcs11_init(!options.batch_mode) == 0) &&
+ (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
+ &keys)) > 0) {
+ for (i = 0; i < nkeys; i++) {
+ if (n_ids >= SSH_MAX_IDENTITY_FILES) {
+ key_free(keys[i]);
+ continue;
+ }
+ identity_keys[n_ids] = keys[i];
+ identity_files[n_ids] =
+ xstrdup(options.pkcs11_provider); /* XXX */
+ n_ids++;
+ }
+ xfree(keys);
+ }
+#endif /* ENABLE_PKCS11 */
+ if ((pw = getpwuid(original_real_uid)) == NULL)
+ fatal("load_public_identity_files: getpwuid failed");
+ pwname = xstrdup(pw->pw_name);
+ pwdir = xstrdup(pw->pw_dir);
+ if (gethostname(thishost, sizeof(thishost)) == -1)
+ fatal("load_public_identity_files: gethostname: %s",
+ strerror(errno));
+ for (i = 0; i < options.num_identity_files; i++) {
+ if (n_ids >= SSH_MAX_IDENTITY_FILES) {
+ xfree(options.identity_files[i]);
+ continue;
+ }
+ cp = tilde_expand_filename(options.identity_files[i],
+ original_real_uid);
+ filename = percent_expand(cp, "d", pwdir,
+ "u", pwname, "l", thishost, "h", host,
+ "r", options.user, (char *)NULL);
+ xfree(cp);
+ public = key_load_public(filename, NULL);
+ debug("identity file %s type %d", filename,
+ public ? public->type : -1);
+ xfree(options.identity_files[i]);
+ identity_files[n_ids] = filename;
+ identity_keys[n_ids] = public;
+
+ if (++n_ids >= SSH_MAX_IDENTITY_FILES)
+ continue;
+
+ /* Try to add the certificate variant too */
+ xasprintf(&cp, "%s-cert", filename);
+ public = key_load_public(cp, NULL);
+ debug("identity file %s type %d", cp,
+ public ? public->type : -1);
+ if (public == NULL) {
+ xfree(cp);
+ continue;
+ }
+ if (!key_is_cert(public)) {
+ debug("%s: key %s type %s is not a certificate",
+ __func__, cp, key_type(public));
+ key_free(public);
+ xfree(cp);
+ continue;
+ }
+ identity_keys[n_ids] = public;
+ /* point to the original path, most likely the private key */
+ identity_files[n_ids] = xstrdup(filename);
+ n_ids++;
+ }
+ options.num_identity_files = n_ids;
+ memcpy(options.identity_files, identity_files, sizeof(identity_files));
+ memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
+
+ bzero(pwname, strlen(pwname));
+ xfree(pwname);
+ bzero(pwdir, strlen(pwdir));
+ xfree(pwdir);
+}
+
+static void
+main_sigchld_handler(int sig)
+{
+ int save_errno = errno;
+ pid_t pid;
+ int status;
+
+ while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
+ (pid < 0 && errno == EINTR))
+ ;
+
+ signal(sig, main_sigchld_handler);
+ errno = save_errno;
+}
+
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