Damien Miller | ece92c8 | 2008-11-03 19:25:03 +1100 | [diff] [blame] | 1 | /* $OpenBSD: sshconnect.c,v 1.212 2008/10/14 18:11:33 stevesk Exp $ */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 2 | /* |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
| 4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| 5 | * All rights reserved |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 6 | * Code to connect to a remote host, and to perform the client side of the |
| 7 | * login (authentication) dialog. |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 8 | * |
| 9 | * As far as I am concerned, the code I have written for this software |
| 10 | * can be used freely for any purpose. Any derived versions of this |
| 11 | * software must be clearly marked as such, and if the derived work is |
| 12 | * incompatible with the protocol description in the RFC file, it must be |
| 13 | * called by a name other than "ssh" or "Secure Shell". |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 14 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 15 | |
| 16 | #include "includes.h" |
Damien Miller | 9cf6d07 | 2006-03-15 11:29:24 +1100 | [diff] [blame] | 17 | |
| 18 | #include <sys/types.h> |
| 19 | #include <sys/wait.h> |
Damien Miller | f17883e | 2006-03-15 11:45:54 +1100 | [diff] [blame] | 20 | #include <sys/stat.h> |
Damien Miller | 8ec8c3e | 2006-07-10 20:35:38 +1000 | [diff] [blame] | 21 | #include <sys/socket.h> |
Damien Miller | 9aec919 | 2006-08-05 10:57:45 +1000 | [diff] [blame] | 22 | #ifdef HAVE_SYS_TIME_H |
| 23 | # include <sys/time.h> |
| 24 | #endif |
Damien Miller | 8ec8c3e | 2006-07-10 20:35:38 +1000 | [diff] [blame] | 25 | |
| 26 | #include <netinet/in.h> |
Darren Tucker | 46aa3e0 | 2006-09-02 15:32:40 +1000 | [diff] [blame] | 27 | #include <arpa/inet.h> |
Damien Miller | 03e2003 | 2006-03-15 11:16:59 +1100 | [diff] [blame] | 28 | |
Damien Miller | c7b0636 | 2006-03-15 11:53:45 +1100 | [diff] [blame] | 29 | #include <ctype.h> |
Darren Tucker | 3997249 | 2006-07-12 22:22:46 +1000 | [diff] [blame] | 30 | #include <errno.h> |
Damien Miller | b8fe89c | 2006-07-24 14:51:00 +1000 | [diff] [blame] | 31 | #include <netdb.h> |
Damien Miller | 6645e7a | 2006-03-15 14:42:54 +1100 | [diff] [blame] | 32 | #ifdef HAVE_PATHS_H |
Damien Miller | 03e2003 | 2006-03-15 11:16:59 +1100 | [diff] [blame] | 33 | #include <paths.h> |
Damien Miller | 6645e7a | 2006-03-15 14:42:54 +1100 | [diff] [blame] | 34 | #endif |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 35 | #include <pwd.h> |
Damien Miller | ded319c | 2006-09-01 15:38:36 +1000 | [diff] [blame] | 36 | #include <stdarg.h> |
Damien Miller | a7a73ee | 2006-08-05 11:37:59 +1000 | [diff] [blame] | 37 | #include <stdio.h> |
Damien Miller | e7a1e5c | 2006-08-05 11:34:19 +1000 | [diff] [blame] | 38 | #include <stdlib.h> |
Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame] | 39 | #include <string.h> |
Damien Miller | e6b3b61 | 2006-07-24 14:01:23 +1000 | [diff] [blame] | 40 | #include <unistd.h> |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 41 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 42 | #include "xmalloc.h" |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 43 | #include "key.h" |
| 44 | #include "hostfile.h" |
| 45 | #include "ssh.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 46 | #include "rsa.h" |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 47 | #include "buffer.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 48 | #include "packet.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 49 | #include "uidswap.h" |
| 50 | #include "compat.h" |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 51 | #include "key.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 52 | #include "sshconnect.h" |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 53 | #include "hostfile.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 54 | #include "log.h" |
| 55 | #include "readconf.h" |
| 56 | #include "atomicio.h" |
| 57 | #include "misc.h" |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 58 | #include "dns.h" |
Damien Miller | b757677 | 2006-07-10 20:23:39 +1000 | [diff] [blame] | 59 | #include "version.h" |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 60 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 61 | char *client_version_string = NULL; |
| 62 | char *server_version_string = NULL; |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 63 | |
Damien Miller | c1af1d5 | 2005-11-05 15:08:57 +1100 | [diff] [blame] | 64 | static int matching_host_key_dns = 0; |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 65 | |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 66 | /* import */ |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 67 | extern Options options; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 68 | extern char *__progname; |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 69 | extern uid_t original_real_uid; |
| 70 | extern uid_t original_effective_uid; |
Damien Miller | 8c4e18a | 2002-09-19 12:05:02 +1000 | [diff] [blame] | 71 | extern pid_t proxy_command_pid; |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 72 | |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 73 | static int show_other_keys(const char *, Key *); |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 74 | static void warn_changed_key(Key *); |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 75 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 76 | /* |
| 77 | * Connect to the given ssh server using a proxy command. |
| 78 | */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 79 | static int |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 80 | ssh_proxy_connect(const char *host, u_short port, const char *proxy_command) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 81 | { |
Damien Miller | 6476cad | 2005-06-16 13:18:34 +1000 | [diff] [blame] | 82 | char *command_string, *tmp; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 83 | int pin[2], pout[2]; |
Damien Miller | 166fca8 | 2000-04-20 07:42:21 +1000 | [diff] [blame] | 84 | pid_t pid; |
Damien Miller | 1d824ab | 2007-09-17 11:58:04 +1000 | [diff] [blame] | 85 | char *shell, strport[NI_MAXSERV]; |
| 86 | |
| 87 | if ((shell = getenv("SHELL")) == NULL) |
| 88 | shell = _PATH_BSHELL; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 89 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 90 | /* Convert the port number into a string. */ |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 91 | snprintf(strport, sizeof strport, "%hu", port); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 92 | |
Damien Miller | 8c4e18a | 2002-09-19 12:05:02 +1000 | [diff] [blame] | 93 | /* |
| 94 | * Build the final command string in the buffer by making the |
| 95 | * appropriate substitutions to the given proxy command. |
| 96 | * |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 97 | * Use "exec" to avoid "sh -c" processes on some platforms |
Damien Miller | 8c4e18a | 2002-09-19 12:05:02 +1000 | [diff] [blame] | 98 | * (e.g. Solaris) |
| 99 | */ |
Damien Miller | 07d86be | 2006-03-26 14:19:21 +1100 | [diff] [blame] | 100 | xasprintf(&tmp, "exec %s", proxy_command); |
Damien Miller | 6476cad | 2005-06-16 13:18:34 +1000 | [diff] [blame] | 101 | command_string = percent_expand(tmp, "h", host, |
| 102 | "p", strport, (char *)NULL); |
| 103 | xfree(tmp); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 104 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 105 | /* Create pipes for communicating with the proxy. */ |
| 106 | if (pipe(pin) < 0 || pipe(pout) < 0) |
| 107 | fatal("Could not create pipes to communicate with the proxy: %.100s", |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 108 | strerror(errno)); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 109 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 110 | debug("Executing proxy command: %.500s", command_string); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 111 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 112 | /* Fork and execute the proxy command. */ |
| 113 | if ((pid = fork()) == 0) { |
| 114 | char *argv[10]; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 115 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 116 | /* Child. Permanently give up superuser privileges. */ |
Damien Miller | 2e5fe88 | 2006-06-13 13:10:00 +1000 | [diff] [blame] | 117 | permanently_drop_suid(original_real_uid); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 118 | |
| 119 | /* Redirect stdin and stdout. */ |
| 120 | close(pin[1]); |
| 121 | if (pin[0] != 0) { |
| 122 | if (dup2(pin[0], 0) < 0) |
| 123 | perror("dup2 stdin"); |
| 124 | close(pin[0]); |
| 125 | } |
| 126 | close(pout[0]); |
| 127 | if (dup2(pout[1], 1) < 0) |
| 128 | perror("dup2 stdout"); |
| 129 | /* Cannot be 1 because pin allocated two descriptors. */ |
| 130 | close(pout[1]); |
| 131 | |
| 132 | /* Stderr is left as it is so that error messages get |
| 133 | printed on the user's terminal. */ |
Damien Miller | 1d824ab | 2007-09-17 11:58:04 +1000 | [diff] [blame] | 134 | argv[0] = shell; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 135 | argv[1] = "-c"; |
| 136 | argv[2] = command_string; |
| 137 | argv[3] = NULL; |
| 138 | |
| 139 | /* Execute the proxy command. Note that we gave up any |
| 140 | extra privileges above. */ |
Kevin Steves | fcd5d60 | 2001-01-07 11:45:22 +0000 | [diff] [blame] | 141 | execv(argv[0], argv); |
| 142 | perror(argv[0]); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 143 | exit(1); |
| 144 | } |
| 145 | /* Parent. */ |
| 146 | if (pid < 0) |
| 147 | fatal("fork failed: %.100s", strerror(errno)); |
Damien Miller | 8c4e18a | 2002-09-19 12:05:02 +1000 | [diff] [blame] | 148 | else |
| 149 | proxy_command_pid = pid; /* save pid to clean up later */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 150 | |
| 151 | /* Close child side of the descriptors. */ |
| 152 | close(pin[0]); |
| 153 | close(pout[1]); |
| 154 | |
| 155 | /* Free the command name. */ |
Damien Miller | 6476cad | 2005-06-16 13:18:34 +1000 | [diff] [blame] | 156 | xfree(command_string); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 157 | |
| 158 | /* Set the connection file descriptors. */ |
| 159 | packet_set_connection(pout[0], pin[1]); |
Darren Tucker | 3fc464e | 2008-06-13 06:42:45 +1000 | [diff] [blame] | 160 | packet_set_timeout(options.server_alive_interval, |
| 161 | options.server_alive_count_max); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 162 | |
Ben Lindstrom | f9cedb9 | 2001-08-06 21:07:11 +0000 | [diff] [blame] | 163 | /* Indicate OK return */ |
| 164 | return 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 165 | } |
| 166 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 167 | /* |
| 168 | * Creates a (possibly privileged) socket for use as the ssh connection. |
| 169 | */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 170 | static int |
Damien Miller | 2372ace | 2003-05-14 13:42:23 +1000 | [diff] [blame] | 171 | ssh_create_socket(int privileged, struct addrinfo *ai) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 172 | { |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 173 | int sock, gaierr; |
| 174 | struct addrinfo hints, *res; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 175 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 176 | /* |
| 177 | * If we are running as root and want to connect to a privileged |
| 178 | * port, bind our own socket to a privileged port. |
| 179 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 180 | if (privileged) { |
| 181 | int p = IPPORT_RESERVED - 1; |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 182 | PRIV_START; |
Damien Miller | 2372ace | 2003-05-14 13:42:23 +1000 | [diff] [blame] | 183 | sock = rresvport_af(&p, ai->ai_family); |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 184 | PRIV_END; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 185 | if (sock < 0) |
Damien Miller | 2372ace | 2003-05-14 13:42:23 +1000 | [diff] [blame] | 186 | error("rresvport: af=%d %.100s", ai->ai_family, |
| 187 | strerror(errno)); |
Damien Miller | 98c7ad6 | 2000-03-09 21:27:49 +1100 | [diff] [blame] | 188 | else |
| 189 | debug("Allocated local port %d.", p); |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 190 | return sock; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 191 | } |
Damien Miller | 2372ace | 2003-05-14 13:42:23 +1000 | [diff] [blame] | 192 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 193 | if (sock < 0) |
| 194 | error("socket: %.100s", strerror(errno)); |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 195 | |
| 196 | /* Bind the socket to an alternative local IP address */ |
| 197 | if (options.bind_address == NULL) |
| 198 | return sock; |
| 199 | |
| 200 | memset(&hints, 0, sizeof(hints)); |
Damien Miller | 2372ace | 2003-05-14 13:42:23 +1000 | [diff] [blame] | 201 | hints.ai_family = ai->ai_family; |
| 202 | hints.ai_socktype = ai->ai_socktype; |
| 203 | hints.ai_protocol = ai->ai_protocol; |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 204 | hints.ai_flags = AI_PASSIVE; |
Darren Tucker | 30ac73b | 2008-06-13 04:46:45 +1000 | [diff] [blame] | 205 | gaierr = getaddrinfo(options.bind_address, NULL, &hints, &res); |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 206 | if (gaierr) { |
| 207 | error("getaddrinfo: %s: %s", options.bind_address, |
Darren Tucker | 4abde77 | 2007-12-29 02:43:51 +1100 | [diff] [blame] | 208 | ssh_gai_strerror(gaierr)); |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 209 | close(sock); |
| 210 | return -1; |
| 211 | } |
| 212 | if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) { |
| 213 | error("bind: %s: %s", options.bind_address, strerror(errno)); |
| 214 | close(sock); |
| 215 | freeaddrinfo(res); |
| 216 | return -1; |
| 217 | } |
| 218 | freeaddrinfo(res); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 219 | return sock; |
| 220 | } |
| 221 | |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 222 | static int |
| 223 | timeout_connect(int sockfd, const struct sockaddr *serv_addr, |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 224 | socklen_t addrlen, int *timeoutp) |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 225 | { |
| 226 | fd_set *fdset; |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 227 | struct timeval tv, t_start; |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 228 | socklen_t optlen; |
Damien Miller | 07d86be | 2006-03-26 14:19:21 +1100 | [diff] [blame] | 229 | int optval, rc, result = -1; |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 230 | |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 231 | gettimeofday(&t_start, NULL); |
| 232 | |
| 233 | if (*timeoutp <= 0) { |
| 234 | result = connect(sockfd, serv_addr, addrlen); |
| 235 | goto done; |
| 236 | } |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 237 | |
Damien Miller | f6723f0 | 2004-01-27 21:21:27 +1100 | [diff] [blame] | 238 | set_nonblock(sockfd); |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 239 | rc = connect(sockfd, serv_addr, addrlen); |
Damien Miller | f6723f0 | 2004-01-27 21:21:27 +1100 | [diff] [blame] | 240 | if (rc == 0) { |
| 241 | unset_nonblock(sockfd); |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 242 | result = 0; |
| 243 | goto done; |
Damien Miller | f6723f0 | 2004-01-27 21:21:27 +1100 | [diff] [blame] | 244 | } |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 245 | if (errno != EINPROGRESS) { |
| 246 | result = -1; |
| 247 | goto done; |
| 248 | } |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 249 | |
Damien Miller | 07d86be | 2006-03-26 14:19:21 +1100 | [diff] [blame] | 250 | fdset = (fd_set *)xcalloc(howmany(sockfd + 1, NFDBITS), |
| 251 | sizeof(fd_mask)); |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 252 | FD_SET(sockfd, fdset); |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 253 | ms_to_timeval(&tv, *timeoutp); |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 254 | |
Darren Tucker | 47eede7 | 2005-03-14 23:08:12 +1100 | [diff] [blame] | 255 | for (;;) { |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 256 | rc = select(sockfd + 1, NULL, fdset, NULL, &tv); |
| 257 | if (rc != -1 || errno != EINTR) |
| 258 | break; |
| 259 | } |
| 260 | |
Darren Tucker | 47eede7 | 2005-03-14 23:08:12 +1100 | [diff] [blame] | 261 | switch (rc) { |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 262 | case 0: |
| 263 | /* Timed out */ |
| 264 | errno = ETIMEDOUT; |
Damien Miller | 08293fa | 2003-05-23 18:44:41 +1000 | [diff] [blame] | 265 | break; |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 266 | case -1: |
| 267 | /* Select error */ |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 268 | debug("select: %s", strerror(errno)); |
Damien Miller | 08293fa | 2003-05-23 18:44:41 +1000 | [diff] [blame] | 269 | break; |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 270 | case 1: |
| 271 | /* Completed or failed */ |
| 272 | optval = 0; |
| 273 | optlen = sizeof(optval); |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 274 | if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, |
Darren Tucker | bd5361b | 2003-09-22 20:59:16 +1000 | [diff] [blame] | 275 | &optlen) == -1) { |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 276 | debug("getsockopt: %s", strerror(errno)); |
Damien Miller | 08293fa | 2003-05-23 18:44:41 +1000 | [diff] [blame] | 277 | break; |
Darren Tucker | bd5361b | 2003-09-22 20:59:16 +1000 | [diff] [blame] | 278 | } |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 279 | if (optval != 0) { |
| 280 | errno = optval; |
Damien Miller | 08293fa | 2003-05-23 18:44:41 +1000 | [diff] [blame] | 281 | break; |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 282 | } |
Damien Miller | 08293fa | 2003-05-23 18:44:41 +1000 | [diff] [blame] | 283 | result = 0; |
Damien Miller | f6723f0 | 2004-01-27 21:21:27 +1100 | [diff] [blame] | 284 | unset_nonblock(sockfd); |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 285 | break; |
| 286 | default: |
| 287 | /* Should not occur */ |
| 288 | fatal("Bogus return (%d) from select()", rc); |
| 289 | } |
| 290 | |
Damien Miller | 08293fa | 2003-05-23 18:44:41 +1000 | [diff] [blame] | 291 | xfree(fdset); |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 292 | |
| 293 | done: |
| 294 | if (result == 0 && *timeoutp > 0) { |
| 295 | ms_subtract_diff(&t_start, timeoutp); |
| 296 | if (*timeoutp <= 0) { |
| 297 | errno = ETIMEDOUT; |
| 298 | result = -1; |
| 299 | } |
| 300 | } |
| 301 | |
Damien Miller | 08293fa | 2003-05-23 18:44:41 +1000 | [diff] [blame] | 302 | return (result); |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 303 | } |
| 304 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 305 | /* |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 306 | * Opens a TCP/IP connection to the remote server on the given host. |
| 307 | * The address of the remote host will be returned in hostaddr. |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 308 | * If port is 0, the default port will be used. If needpriv is true, |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 309 | * a privileged port will be allocated to make the connection. |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 310 | * This requires super-user privileges if needpriv is true. |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 311 | * Connection_attempts specifies the maximum number of tries (one per |
| 312 | * second). If proxy_command is non-NULL, it specifies the command (with %h |
| 313 | * and %p substituted for host and port, respectively) to use to contact |
| 314 | * the daemon. |
| 315 | */ |
| 316 | int |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 317 | ssh_connect(const char *host, struct sockaddr_storage * hostaddr, |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 318 | u_short port, int family, int connection_attempts, int *timeout_ms, |
| 319 | int want_keepalive, int needpriv, const char *proxy_command) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 320 | { |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 321 | int gaierr; |
Ben Lindstrom | bf555ba | 2001-01-18 02:04:35 +0000 | [diff] [blame] | 322 | int on = 1; |
| 323 | int sock = -1, attempt; |
| 324 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
| 325 | struct addrinfo hints, *ai, *aitop; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 326 | |
Ben Lindstrom | 064496f | 2002-12-23 02:04:22 +0000 | [diff] [blame] | 327 | debug2("ssh_connect: needpriv %d", needpriv); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 328 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 329 | /* If a proxy command is given, connect using it. */ |
| 330 | if (proxy_command != NULL) |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 331 | return ssh_proxy_connect(host, port, proxy_command); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 332 | |
| 333 | /* No proxy command. */ |
| 334 | |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 335 | memset(&hints, 0, sizeof(hints)); |
Damien Miller | 139d4cd | 2001-10-10 15:07:44 +1000 | [diff] [blame] | 336 | hints.ai_family = family; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 337 | hints.ai_socktype = SOCK_STREAM; |
Ben Lindstrom | 5c38552 | 2002-06-23 21:23:20 +0000 | [diff] [blame] | 338 | snprintf(strport, sizeof strport, "%u", port); |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 339 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) |
Darren Tucker | 4abde77 | 2007-12-29 02:43:51 +1100 | [diff] [blame] | 340 | fatal("%s: Could not resolve hostname %.100s: %s", __progname, |
| 341 | host, ssh_gai_strerror(gaierr)); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 342 | |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 343 | for (attempt = 0; attempt < connection_attempts; attempt++) { |
Damien Miller | f4bcd10 | 2006-10-24 03:02:23 +1000 | [diff] [blame] | 344 | if (attempt > 0) { |
| 345 | /* Sleep a moment before retrying. */ |
| 346 | sleep(1); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 347 | debug("Trying again..."); |
Damien Miller | f4bcd10 | 2006-10-24 03:02:23 +1000 | [diff] [blame] | 348 | } |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 349 | /* |
| 350 | * Loop through addresses for this host, and try each one in |
| 351 | * sequence until the connection succeeds. |
| 352 | */ |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 353 | for (ai = aitop; ai; ai = ai->ai_next) { |
| 354 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) |
| 355 | continue; |
| 356 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, |
| 357 | ntop, sizeof(ntop), strport, sizeof(strport), |
| 358 | NI_NUMERICHOST|NI_NUMERICSERV) != 0) { |
| 359 | error("ssh_connect: getnameinfo failed"); |
| 360 | continue; |
| 361 | } |
| 362 | debug("Connecting to %.200s [%.100s] port %s.", |
| 363 | host, ntop, strport); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 364 | |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 365 | /* Create a socket for connecting. */ |
Damien Miller | 2372ace | 2003-05-14 13:42:23 +1000 | [diff] [blame] | 366 | sock = ssh_create_socket(needpriv, ai); |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 367 | if (sock < 0) |
Ben Lindstrom | f9cedb9 | 2001-08-06 21:07:11 +0000 | [diff] [blame] | 368 | /* Any error is already output */ |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 369 | continue; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 370 | |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 371 | if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen, |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 372 | timeout_ms) >= 0) { |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 373 | /* Successful connection. */ |
Ben Lindstrom | a370005 | 2001-04-05 23:26:32 +0000 | [diff] [blame] | 374 | memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 375 | break; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 376 | } else { |
Ben Lindstrom | 728aa7e | 2002-07-15 17:48:11 +0000 | [diff] [blame] | 377 | debug("connect to address %s port %s: %s", |
| 378 | ntop, strport, strerror(errno)); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 379 | close(sock); |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 380 | sock = -1; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 381 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 382 | } |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 383 | if (sock != -1) |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 384 | break; /* Successful connection. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 385 | } |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 386 | |
| 387 | freeaddrinfo(aitop); |
| 388 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 389 | /* Return failure if we didn't get a successful connection. */ |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 390 | if (sock == -1) { |
Darren Tucker | b2161e3 | 2005-01-20 11:00:46 +1100 | [diff] [blame] | 391 | error("ssh: connect to host %s port %s: %s", |
Ben Lindstrom | a6cd75c | 2002-07-11 04:00:19 +0000 | [diff] [blame] | 392 | host, strport, strerror(errno)); |
Darren Tucker | b2161e3 | 2005-01-20 11:00:46 +1100 | [diff] [blame] | 393 | return (-1); |
Ben Lindstrom | a6cd75c | 2002-07-11 04:00:19 +0000 | [diff] [blame] | 394 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 395 | |
| 396 | debug("Connection established."); |
| 397 | |
Damien Miller | 12c150e | 2003-12-17 16:31:10 +1100 | [diff] [blame] | 398 | /* Set SO_KEEPALIVE if requested. */ |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 399 | if (want_keepalive && |
Ben Lindstrom | bf555ba | 2001-01-18 02:04:35 +0000 | [diff] [blame] | 400 | setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, |
| 401 | sizeof(on)) < 0) |
| 402 | error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 403 | |
| 404 | /* Set the connection. */ |
| 405 | packet_set_connection(sock, sock); |
Darren Tucker | 3fc464e | 2008-06-13 06:42:45 +1000 | [diff] [blame] | 406 | packet_set_timeout(options.server_alive_interval, |
| 407 | options.server_alive_count_max); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 408 | |
Ben Lindstrom | f9cedb9 | 2001-08-06 21:07:11 +0000 | [diff] [blame] | 409 | return 0; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 410 | } |
| 411 | |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 412 | /* |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 413 | * Waits for the server identification string, and sends our own |
| 414 | * identification string. |
| 415 | */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 416 | static void |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 417 | ssh_exchange_identification(int timeout_ms) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 418 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 419 | char buf[256], remote_version[256]; /* must be same size! */ |
Damien Miller | eccb9de | 2005-06-17 12:59:34 +1000 | [diff] [blame] | 420 | int remote_major, remote_minor, mismatch; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 421 | int connection_in = packet_get_connection_in(); |
| 422 | int connection_out = packet_get_connection_out(); |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 423 | int minor1 = PROTOCOL_MINOR_1; |
Damien Miller | 1e88ea6 | 2006-07-10 20:15:56 +1000 | [diff] [blame] | 424 | u_int i, n; |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 425 | size_t len; |
| 426 | int fdsetsz, remaining, rc; |
| 427 | struct timeval t_start, t_remaining; |
| 428 | fd_set *fdset; |
| 429 | |
| 430 | fdsetsz = howmany(connection_in + 1, NFDBITS) * sizeof(fd_mask); |
| 431 | fdset = xcalloc(1, fdsetsz); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 432 | |
Damien Miller | b253cc4 | 2005-05-26 12:23:44 +1000 | [diff] [blame] | 433 | /* Read other side's version identification. */ |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 434 | remaining = timeout_ms; |
Damien Miller | 1e88ea6 | 2006-07-10 20:15:56 +1000 | [diff] [blame] | 435 | for (n = 0;;) { |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 436 | for (i = 0; i < sizeof(buf) - 1; i++) { |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 437 | if (timeout_ms > 0) { |
| 438 | gettimeofday(&t_start, NULL); |
| 439 | ms_to_timeval(&t_remaining, remaining); |
| 440 | FD_SET(connection_in, fdset); |
| 441 | rc = select(connection_in + 1, fdset, NULL, |
| 442 | fdset, &t_remaining); |
| 443 | ms_subtract_diff(&t_start, &remaining); |
| 444 | if (rc == 0 || remaining <= 0) |
| 445 | fatal("Connection timed out during " |
| 446 | "banner exchange"); |
| 447 | if (rc == -1) { |
| 448 | if (errno == EINTR) |
| 449 | continue; |
| 450 | fatal("ssh_exchange_identification: " |
| 451 | "select: %s", strerror(errno)); |
| 452 | } |
| 453 | } |
| 454 | |
| 455 | len = atomicio(read, connection_in, &buf[i], 1); |
Damien Miller | b253cc4 | 2005-05-26 12:23:44 +1000 | [diff] [blame] | 456 | |
Damien Miller | 46d38de | 2005-07-17 17:02:09 +1000 | [diff] [blame] | 457 | if (len != 1 && errno == EPIPE) |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 458 | fatal("ssh_exchange_identification: " |
| 459 | "Connection closed by remote host"); |
Damien Miller | b253cc4 | 2005-05-26 12:23:44 +1000 | [diff] [blame] | 460 | else if (len != 1) |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 461 | fatal("ssh_exchange_identification: " |
| 462 | "read: %.100s", strerror(errno)); |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 463 | if (buf[i] == '\r') { |
| 464 | buf[i] = '\n'; |
| 465 | buf[i + 1] = 0; |
| 466 | continue; /**XXX wait for \n */ |
| 467 | } |
| 468 | if (buf[i] == '\n') { |
| 469 | buf[i + 1] = 0; |
| 470 | break; |
| 471 | } |
Damien Miller | 1e88ea6 | 2006-07-10 20:15:56 +1000 | [diff] [blame] | 472 | if (++n > 65536) |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 473 | fatal("ssh_exchange_identification: " |
| 474 | "No banner received"); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 475 | } |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 476 | buf[sizeof(buf) - 1] = 0; |
| 477 | if (strncmp(buf, "SSH-", 4) == 0) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 478 | break; |
Damien Miller | f6d9e22 | 2000-06-18 14:50:44 +1000 | [diff] [blame] | 479 | debug("ssh_exchange_identification: %s", buf); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 480 | } |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 481 | server_version_string = xstrdup(buf); |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 482 | xfree(fdset); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 483 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 484 | /* |
| 485 | * Check that the versions match. In future this might accept |
| 486 | * several versions and set appropriate flags to handle them. |
| 487 | */ |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 488 | if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n", |
| 489 | &remote_major, &remote_minor, remote_version) != 3) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 490 | fatal("Bad remote protocol version identification: '%.100s'", buf); |
| 491 | debug("Remote protocol version %d.%d, remote software version %.100s", |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 492 | remote_major, remote_minor, remote_version); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 493 | |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 494 | compat_datafellows(remote_version); |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 495 | mismatch = 0; |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 496 | |
Ben Lindstrom | 1c37c6a | 2001-12-06 18:00:18 +0000 | [diff] [blame] | 497 | switch (remote_major) { |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 498 | case 1: |
| 499 | if (remote_minor == 99 && |
| 500 | (options.protocol & SSH_PROTO_2) && |
| 501 | !(options.protocol & SSH_PROTO_1_PREFERRED)) { |
| 502 | enable_compat20(); |
| 503 | break; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 504 | } |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 505 | if (!(options.protocol & SSH_PROTO_1)) { |
| 506 | mismatch = 1; |
| 507 | break; |
| 508 | } |
| 509 | if (remote_minor < 3) { |
| 510 | fatal("Remote machine has too old SSH software version."); |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 511 | } else if (remote_minor == 3 || remote_minor == 4) { |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 512 | /* We speak 1.3, too. */ |
| 513 | enable_compat13(); |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 514 | minor1 = 3; |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 515 | if (options.forward_agent) { |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 516 | logit("Agent forwarding disabled for protocol 1.3"); |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 517 | options.forward_agent = 0; |
| 518 | } |
| 519 | } |
| 520 | break; |
| 521 | case 2: |
| 522 | if (options.protocol & SSH_PROTO_2) { |
| 523 | enable_compat20(); |
| 524 | break; |
| 525 | } |
| 526 | /* FALLTHROUGH */ |
Damien Miller | 4af5130 | 2000-04-16 11:18:38 +1000 | [diff] [blame] | 527 | default: |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 528 | mismatch = 1; |
| 529 | break; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 530 | } |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 531 | if (mismatch) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 532 | fatal("Protocol major versions differ: %d vs. %d", |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 533 | (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, |
| 534 | remote_major); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 535 | /* Send our own protocol version identification. */ |
Darren Tucker | d7bdc0c | 2008-07-02 22:34:30 +1000 | [diff] [blame] | 536 | snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s%s", |
Damien Miller | 7892879 | 2000-04-12 20:17:38 +1000 | [diff] [blame] | 537 | compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 538 | compat20 ? PROTOCOL_MINOR_2 : minor1, |
Darren Tucker | d7bdc0c | 2008-07-02 22:34:30 +1000 | [diff] [blame] | 539 | SSH_VERSION, compat20 ? "\r\n" : "\n"); |
Darren Tucker | 9f63f22 | 2003-07-03 13:46:56 +1000 | [diff] [blame] | 540 | if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf)) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 541 | fatal("write: %.100s", strerror(errno)); |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 542 | client_version_string = xstrdup(buf); |
| 543 | chop(client_version_string); |
| 544 | chop(server_version_string); |
| 545 | debug("Local version string %.100s", client_version_string); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 546 | } |
| 547 | |
Ben Lindstrom | b6c06d9 | 2001-02-10 23:21:09 +0000 | [diff] [blame] | 548 | /* defaults to 'no' */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 549 | static int |
Damien Miller | e398004 | 2001-10-10 15:02:03 +1000 | [diff] [blame] | 550 | confirm(const char *prompt) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 551 | { |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 552 | const char *msg, *again = "Please type 'yes' or 'no': "; |
| 553 | char *p; |
| 554 | int ret = -1; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 555 | |
Ben Lindstrom | b6c06d9 | 2001-02-10 23:21:09 +0000 | [diff] [blame] | 556 | if (options.batch_mode) |
| 557 | return 0; |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 558 | for (msg = prompt;;msg = again) { |
| 559 | p = read_passphrase(msg, RP_ECHO); |
| 560 | if (p == NULL || |
| 561 | (p[0] == '\0') || (p[0] == '\n') || |
| 562 | strncasecmp(p, "no", 2) == 0) |
| 563 | ret = 0; |
Ben Lindstrom | 04f9af7 | 2002-07-04 00:03:56 +0000 | [diff] [blame] | 564 | if (p && strncasecmp(p, "yes", 3) == 0) |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 565 | ret = 1; |
| 566 | if (p) |
| 567 | xfree(p); |
| 568 | if (ret != -1) |
| 569 | return ret; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 570 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 571 | } |
| 572 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 573 | /* |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 574 | * check whether the supplied host key is valid, return -1 if the key |
| 575 | * is not valid. the user_hostfile will not be updated if 'readonly' is true. |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 576 | */ |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 577 | #define RDRW 0 |
| 578 | #define RDONLY 1 |
| 579 | #define ROQUIET 2 |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 580 | static int |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 581 | check_host_key(char *hostname, struct sockaddr *hostaddr, u_short port, |
| 582 | Key *host_key, int readonly, const char *user_hostfile, |
| 583 | const char *system_hostfile) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 584 | { |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 585 | Key *file_key; |
Damien Miller | f58b58c | 2003-11-17 21:18:23 +1100 | [diff] [blame] | 586 | const char *type = key_type(host_key); |
Darren Tucker | da34553 | 2006-07-10 23:04:19 +1000 | [diff] [blame] | 587 | char *ip = NULL, *host = NULL; |
Darren Tucker | 9c16ac9 | 2008-06-13 04:40:35 +1000 | [diff] [blame] | 588 | char hostline[1000], *hostp, *fp, *ra; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 589 | HostStatus host_status; |
| 590 | HostStatus ip_status; |
Damien Miller | 1227d4c | 2005-03-02 12:06:51 +1100 | [diff] [blame] | 591 | int r, local = 0, host_ip_differ = 0; |
Damien Miller | eaf9994 | 2000-01-19 13:45:07 +1100 | [diff] [blame] | 592 | int salen; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 593 | char ntop[NI_MAXHOST]; |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 594 | char msg[1024]; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 595 | int len, host_line, ip_line, cancelled_forwarding = 0; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 596 | const char *host_file = NULL, *ip_file = NULL; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 597 | |
| 598 | /* |
| 599 | * Force accepting of the host key for loopback/localhost. The |
| 600 | * problem is that if the home directory is NFS-mounted to multiple |
| 601 | * machines, localhost will refer to a different machine in each of |
| 602 | * them, and the user will get bogus HOST_CHANGED warnings. This |
| 603 | * essentially disables host authentication for localhost; however, |
| 604 | * this is probably not a real problem. |
| 605 | */ |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 606 | /** hostaddr == 0! */ |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 607 | switch (hostaddr->sa_family) { |
| 608 | case AF_INET: |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 609 | local = (ntohl(((struct sockaddr_in *)hostaddr)-> |
Damien Miller | 0dc1bef | 2005-07-17 17:22:45 +1000 | [diff] [blame] | 610 | sin_addr.s_addr) >> 24) == IN_LOOPBACKNET; |
Damien Miller | eaf9994 | 2000-01-19 13:45:07 +1100 | [diff] [blame] | 611 | salen = sizeof(struct sockaddr_in); |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 612 | break; |
| 613 | case AF_INET6: |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 614 | local = IN6_IS_ADDR_LOOPBACK( |
| 615 | &(((struct sockaddr_in6 *)hostaddr)->sin6_addr)); |
Damien Miller | eaf9994 | 2000-01-19 13:45:07 +1100 | [diff] [blame] | 616 | salen = sizeof(struct sockaddr_in6); |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 617 | break; |
| 618 | default: |
| 619 | local = 0; |
Damien Miller | eaf9994 | 2000-01-19 13:45:07 +1100 | [diff] [blame] | 620 | salen = sizeof(struct sockaddr_storage); |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 621 | break; |
| 622 | } |
Ben Lindstrom | 3cecc9a | 2001-10-03 17:39:38 +0000 | [diff] [blame] | 623 | if (options.no_host_authentication_for_localhost == 1 && local && |
| 624 | options.host_key_alias == NULL) { |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 625 | debug("Forcing accepting of host key for " |
| 626 | "loopback/localhost."); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 627 | return 0; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 628 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 629 | |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 630 | /* |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 631 | * We don't have the remote ip-address for connections |
| 632 | * using a proxy command |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 633 | */ |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 634 | if (options.proxy_command == NULL) { |
| 635 | if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop), |
| 636 | NULL, 0, NI_NUMERICHOST) != 0) |
| 637 | fatal("check_host_key: getnameinfo failed"); |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 638 | ip = put_host_port(ntop, port); |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 639 | } else { |
| 640 | ip = xstrdup("<no hostip for proxy command>"); |
| 641 | } |
Darren Tucker | 78913e0 | 2008-06-13 04:47:34 +1000 | [diff] [blame] | 642 | |
| 643 | /* |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 644 | * Turn off check_host_ip if the connection is to localhost, via proxy |
| 645 | * command or if we don't have a hostname to compare with |
| 646 | */ |
Darren Tucker | da34553 | 2006-07-10 23:04:19 +1000 | [diff] [blame] | 647 | if (options.check_host_ip && (local || |
| 648 | strcmp(hostname, ip) == 0 || options.proxy_command != NULL)) |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 649 | options.check_host_ip = 0; |
| 650 | |
Damien Miller | a34a28b | 1999-12-14 10:47:15 +1100 | [diff] [blame] | 651 | /* |
Darren Tucker | da34553 | 2006-07-10 23:04:19 +1000 | [diff] [blame] | 652 | * Allow the user to record the key under a different name or |
| 653 | * differentiate a non-standard port. This is useful for ssh |
| 654 | * tunneling over forwarded connections or if you run multiple |
| 655 | * sshd's on different ports on the same machine. |
Ben Lindstrom | 4dccfa5 | 2000-12-28 16:40:05 +0000 | [diff] [blame] | 656 | */ |
| 657 | if (options.host_key_alias != NULL) { |
Darren Tucker | da34553 | 2006-07-10 23:04:19 +1000 | [diff] [blame] | 658 | host = xstrdup(options.host_key_alias); |
Ben Lindstrom | 4dccfa5 | 2000-12-28 16:40:05 +0000 | [diff] [blame] | 659 | debug("using hostkeyalias: %s", host); |
Darren Tucker | da34553 | 2006-07-10 23:04:19 +1000 | [diff] [blame] | 660 | } else { |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 661 | host = put_host_port(hostname, port); |
Ben Lindstrom | 4dccfa5 | 2000-12-28 16:40:05 +0000 | [diff] [blame] | 662 | } |
| 663 | |
| 664 | /* |
Damien Miller | a34a28b | 1999-12-14 10:47:15 +1100 | [diff] [blame] | 665 | * Store the host key from the known host file in here so that we can |
| 666 | * compare it with the key for the IP address. |
| 667 | */ |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 668 | file_key = key_new(host_key->type); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 669 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 670 | /* |
Damien Miller | 788f212 | 2005-11-05 15:14:59 +1100 | [diff] [blame] | 671 | * Check if the host key is present in the user's list of known |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 672 | * hosts or in the systemwide list. |
| 673 | */ |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 674 | host_file = user_hostfile; |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 675 | host_status = check_host_in_hostfile(host_file, host, host_key, |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 676 | file_key, &host_line); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 677 | if (host_status == HOST_NEW) { |
| 678 | host_file = system_hostfile; |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 679 | host_status = check_host_in_hostfile(host_file, host, host_key, |
| 680 | file_key, &host_line); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 681 | } |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 682 | /* |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 683 | * Also perform check for the ip address, skip the check if we are |
| 684 | * localhost or the hostname was an ip address to begin with |
| 685 | */ |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 686 | if (options.check_host_ip) { |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 687 | Key *ip_key = key_new(host_key->type); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 688 | |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 689 | ip_file = user_hostfile; |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 690 | ip_status = check_host_in_hostfile(ip_file, ip, host_key, |
| 691 | ip_key, &ip_line); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 692 | if (ip_status == HOST_NEW) { |
| 693 | ip_file = system_hostfile; |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 694 | ip_status = check_host_in_hostfile(ip_file, ip, |
| 695 | host_key, ip_key, &ip_line); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 696 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 697 | if (host_status == HOST_CHANGED && |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 698 | (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key))) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 699 | host_ip_differ = 1; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 700 | |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 701 | key_free(ip_key); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 702 | } else |
| 703 | ip_status = host_status; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 704 | |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 705 | key_free(file_key); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 706 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 707 | switch (host_status) { |
| 708 | case HOST_OK: |
| 709 | /* The host is known and the key matches. */ |
Damien Miller | e247cc4 | 2000-05-07 12:03:14 +1000 | [diff] [blame] | 710 | debug("Host '%.200s' is known and matches the %s host key.", |
| 711 | host, type); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 712 | debug("Found key in %s:%d", host_file, host_line); |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 713 | if (options.check_host_ip && ip_status == HOST_NEW) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 714 | if (readonly) |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 715 | logit("%s host key for IP address " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 716 | "'%.128s' not in list of known hosts.", |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 717 | type, ip); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 718 | else if (!add_host_to_hostfile(user_hostfile, ip, |
Damien Miller | e177615 | 2005-03-01 21:47:37 +1100 | [diff] [blame] | 719 | host_key, options.hash_known_hosts)) |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 720 | logit("Failed to add the %s host key for IP " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 721 | "address '%.128s' to the list of known " |
| 722 | "hosts (%.30s).", type, ip, user_hostfile); |
| 723 | else |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 724 | logit("Warning: Permanently added the %s host " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 725 | "key for IP address '%.128s' to the list " |
| 726 | "of known hosts.", type, ip); |
Damien Miller | 1028824 | 2008-06-30 00:04:03 +1000 | [diff] [blame] | 727 | } else if (options.visual_host_key) { |
Darren Tucker | 9c16ac9 | 2008-06-13 04:40:35 +1000 | [diff] [blame] | 728 | fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); |
| 729 | ra = key_fingerprint(host_key, SSH_FP_MD5, |
| 730 | SSH_FP_RANDOMART); |
| 731 | logit("Host key fingerprint is %s\n%s\n", fp, ra); |
| 732 | xfree(ra); |
| 733 | xfree(fp); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 734 | } |
| 735 | break; |
| 736 | case HOST_NEW: |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 737 | if (options.host_key_alias == NULL && port != 0 && |
| 738 | port != SSH_DEFAULT_PORT) { |
| 739 | debug("checking without port identifier"); |
Damien Miller | ece92c8 | 2008-11-03 19:25:03 +1100 | [diff] [blame] | 740 | if (check_host_key(hostname, hostaddr, 0, host_key, |
| 741 | ROQUIET, user_hostfile, system_hostfile) == 0) { |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 742 | debug("found matching key w/out port"); |
| 743 | break; |
| 744 | } |
| 745 | } |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 746 | if (readonly) |
| 747 | goto fail; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 748 | /* The host is new. */ |
| 749 | if (options.strict_host_key_checking == 1) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 750 | /* |
| 751 | * User has requested strict host key checking. We |
| 752 | * will not add the host key automatically. The only |
| 753 | * alternative left is to abort. |
| 754 | */ |
| 755 | error("No %s host key is known for %.200s and you " |
| 756 | "have requested strict checking.", type, host); |
| 757 | goto fail; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 758 | } else if (options.strict_host_key_checking == 2) { |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 759 | char msg1[1024], msg2[1024]; |
| 760 | |
| 761 | if (show_other_keys(host, host_key)) |
| 762 | snprintf(msg1, sizeof(msg1), |
Damien Miller | 0dc1bef | 2005-07-17 17:22:45 +1000 | [diff] [blame] | 763 | "\nbut keys of different type are already" |
| 764 | " known for this host."); |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 765 | else |
| 766 | snprintf(msg1, sizeof(msg1), "."); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 767 | /* The default */ |
Ben Lindstrom | cfccef9 | 2001-03-13 04:57:58 +0000 | [diff] [blame] | 768 | fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); |
Darren Tucker | 9c16ac9 | 2008-06-13 04:40:35 +1000 | [diff] [blame] | 769 | ra = key_fingerprint(host_key, SSH_FP_MD5, |
| 770 | SSH_FP_RANDOMART); |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 771 | msg2[0] = '\0'; |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 772 | if (options.verify_host_key_dns) { |
Damien Miller | 150b557 | 2003-11-17 21:19:29 +1100 | [diff] [blame] | 773 | if (matching_host_key_dns) |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 774 | snprintf(msg2, sizeof(msg2), |
| 775 | "Matching host key fingerprint" |
| 776 | " found in DNS.\n"); |
| 777 | else |
| 778 | snprintf(msg2, sizeof(msg2), |
| 779 | "No matching host key fingerprint" |
| 780 | " found in DNS.\n"); |
| 781 | } |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 782 | snprintf(msg, sizeof(msg), |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 783 | "The authenticity of host '%.200s (%s)' can't be " |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 784 | "established%s\n" |
Damien Miller | 1028824 | 2008-06-30 00:04:03 +1000 | [diff] [blame] | 785 | "%s key fingerprint is %s.%s%s\n%s" |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 786 | "Are you sure you want to continue connecting " |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 787 | "(yes/no)? ", |
Damien Miller | 1028824 | 2008-06-30 00:04:03 +1000 | [diff] [blame] | 788 | host, ip, msg1, type, fp, |
| 789 | options.visual_host_key ? "\n" : "", |
| 790 | options.visual_host_key ? ra : "", |
| 791 | msg2); |
Darren Tucker | 9c16ac9 | 2008-06-13 04:40:35 +1000 | [diff] [blame] | 792 | xfree(ra); |
Ben Lindstrom | cfccef9 | 2001-03-13 04:57:58 +0000 | [diff] [blame] | 793 | xfree(fp); |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 794 | if (!confirm(msg)) |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 795 | goto fail; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 796 | } |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 797 | /* |
| 798 | * If not in strict mode, add the key automatically to the |
| 799 | * local known_hosts file. |
| 800 | */ |
Damien Miller | 1227d4c | 2005-03-02 12:06:51 +1100 | [diff] [blame] | 801 | if (options.check_host_ip && ip_status == HOST_NEW) { |
| 802 | snprintf(hostline, sizeof(hostline), "%s,%s", |
| 803 | host, ip); |
| 804 | hostp = hostline; |
| 805 | if (options.hash_known_hosts) { |
| 806 | /* Add hash of host and IP separately */ |
| 807 | r = add_host_to_hostfile(user_hostfile, host, |
| 808 | host_key, options.hash_known_hosts) && |
| 809 | add_host_to_hostfile(user_hostfile, ip, |
| 810 | host_key, options.hash_known_hosts); |
| 811 | } else { |
| 812 | /* Add unhashed "host,ip" */ |
| 813 | r = add_host_to_hostfile(user_hostfile, |
| 814 | hostline, host_key, |
| 815 | options.hash_known_hosts); |
| 816 | } |
| 817 | } else { |
| 818 | r = add_host_to_hostfile(user_hostfile, host, host_key, |
| 819 | options.hash_known_hosts); |
| 820 | hostp = host; |
| 821 | } |
| 822 | |
| 823 | if (!r) |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 824 | logit("Failed to add the host to the list of known " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 825 | "hosts (%.500s).", user_hostfile); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 826 | else |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 827 | logit("Warning: Permanently added '%.200s' (%s) to the " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 828 | "list of known hosts.", hostp, type); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 829 | break; |
| 830 | case HOST_CHANGED: |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 831 | if (readonly == ROQUIET) |
| 832 | goto fail; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 833 | if (options.check_host_ip && host_ip_differ) { |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 834 | char *key_msg; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 835 | if (ip_status == HOST_NEW) |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 836 | key_msg = "is unknown"; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 837 | else if (ip_status == HOST_OK) |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 838 | key_msg = "is unchanged"; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 839 | else |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 840 | key_msg = "has a different value"; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 841 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
| 842 | error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @"); |
| 843 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
Damien Miller | e247cc4 | 2000-05-07 12:03:14 +1000 | [diff] [blame] | 844 | error("The %s host key for %s has changed,", type, host); |
Darren Tucker | ff4454d | 2008-06-13 10:21:51 +1000 | [diff] [blame] | 845 | error("and the key for the corresponding IP address %s", ip); |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 846 | error("%s. This could either mean that", key_msg); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 847 | error("DNS SPOOFING is happening or the IP address for the host"); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 848 | error("and its host key have changed at the same time."); |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 849 | if (ip_status != HOST_NEW) |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 850 | error("Offending key for IP in %s:%d", ip_file, ip_line); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 851 | } |
| 852 | /* The host key has changed. */ |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 853 | warn_changed_key(host_key); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 854 | error("Add correct host key in %.100s to get rid of this message.", |
Ben Lindstrom | 4dccfa5 | 2000-12-28 16:40:05 +0000 | [diff] [blame] | 855 | user_hostfile); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 856 | error("Offending key in %s:%d", host_file, host_line); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 857 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 858 | /* |
| 859 | * If strict host key checking is in use, the user will have |
| 860 | * to edit the key manually and we can only abort. |
| 861 | */ |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 862 | if (options.strict_host_key_checking) { |
| 863 | error("%s host key for %.200s has changed and you have " |
| 864 | "requested strict checking.", type, host); |
| 865 | goto fail; |
| 866 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 867 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 868 | /* |
| 869 | * If strict host key checking has not been requested, allow |
Damien Miller | 941ac45 | 2003-06-04 20:31:53 +1000 | [diff] [blame] | 870 | * the connection but without MITM-able authentication or |
Damien Miller | 437edb9 | 2006-08-05 09:11:13 +1000 | [diff] [blame] | 871 | * forwarding. |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 872 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 873 | if (options.password_authentication) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 874 | error("Password authentication is disabled to avoid " |
| 875 | "man-in-the-middle attacks."); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 876 | options.password_authentication = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 877 | cancelled_forwarding = 1; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 878 | } |
Damien Miller | 941ac45 | 2003-06-04 20:31:53 +1000 | [diff] [blame] | 879 | if (options.kbd_interactive_authentication) { |
| 880 | error("Keyboard-interactive authentication is disabled" |
| 881 | " to avoid man-in-the-middle attacks."); |
| 882 | options.kbd_interactive_authentication = 0; |
| 883 | options.challenge_response_authentication = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 884 | cancelled_forwarding = 1; |
Damien Miller | 941ac45 | 2003-06-04 20:31:53 +1000 | [diff] [blame] | 885 | } |
| 886 | if (options.challenge_response_authentication) { |
| 887 | error("Challenge/response authentication is disabled" |
| 888 | " to avoid man-in-the-middle attacks."); |
| 889 | options.challenge_response_authentication = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 890 | cancelled_forwarding = 1; |
Damien Miller | 941ac45 | 2003-06-04 20:31:53 +1000 | [diff] [blame] | 891 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 892 | if (options.forward_agent) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 893 | error("Agent forwarding is disabled to avoid " |
| 894 | "man-in-the-middle attacks."); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 895 | options.forward_agent = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 896 | cancelled_forwarding = 1; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 897 | } |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 898 | if (options.forward_x11) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 899 | error("X11 forwarding is disabled to avoid " |
| 900 | "man-in-the-middle attacks."); |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 901 | options.forward_x11 = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 902 | cancelled_forwarding = 1; |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 903 | } |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 904 | if (options.num_local_forwards > 0 || |
| 905 | options.num_remote_forwards > 0) { |
| 906 | error("Port forwarding is disabled to avoid " |
| 907 | "man-in-the-middle attacks."); |
| 908 | options.num_local_forwards = |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 909 | options.num_remote_forwards = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 910 | cancelled_forwarding = 1; |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 911 | } |
Damien Miller | 437edb9 | 2006-08-05 09:11:13 +1000 | [diff] [blame] | 912 | if (options.tun_open != SSH_TUNMODE_NO) { |
| 913 | error("Tunnel forwarding is disabled to avoid " |
| 914 | "man-in-the-middle attacks."); |
| 915 | options.tun_open = SSH_TUNMODE_NO; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 916 | cancelled_forwarding = 1; |
Damien Miller | 437edb9 | 2006-08-05 09:11:13 +1000 | [diff] [blame] | 917 | } |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 918 | if (options.exit_on_forward_failure && cancelled_forwarding) |
| 919 | fatal("Error: forwarding disabled due to host key " |
| 920 | "check failure"); |
| 921 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 922 | /* |
| 923 | * XXX Should permit the user to change to use the new id. |
| 924 | * This could be done by converting the host key to an |
| 925 | * identifying sentence, tell that the host identifies itself |
| 926 | * by that sentence, and ask the user if he/she whishes to |
| 927 | * accept the authentication. |
| 928 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 929 | break; |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 930 | case HOST_FOUND: |
| 931 | fatal("internal error"); |
| 932 | break; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 933 | } |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 934 | |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 935 | if (options.check_host_ip && host_status != HOST_CHANGED && |
| 936 | ip_status == HOST_CHANGED) { |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 937 | snprintf(msg, sizeof(msg), |
| 938 | "Warning: the %s host key for '%.200s' " |
| 939 | "differs from the key for the IP address '%.128s'" |
| 940 | "\nOffending key for IP in %s:%d", |
| 941 | type, host, ip, ip_file, ip_line); |
| 942 | if (host_status == HOST_OK) { |
| 943 | len = strlen(msg); |
| 944 | snprintf(msg + len, sizeof(msg) - len, |
| 945 | "\nMatching host key in %s:%d", |
Ben Lindstrom | cb72e4f | 2002-06-21 00:41:51 +0000 | [diff] [blame] | 946 | host_file, host_line); |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 947 | } |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 948 | if (options.strict_host_key_checking == 1) { |
Damien Miller | ab2db41 | 2003-06-02 19:09:13 +1000 | [diff] [blame] | 949 | logit("%s", msg); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 950 | error("Exiting, you have requested strict checking."); |
| 951 | goto fail; |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 952 | } else if (options.strict_host_key_checking == 2) { |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 953 | strlcat(msg, "\nAre you sure you want " |
| 954 | "to continue connecting (yes/no)? ", sizeof(msg)); |
| 955 | if (!confirm(msg)) |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 956 | goto fail; |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 957 | } else { |
Damien Miller | ab2db41 | 2003-06-02 19:09:13 +1000 | [diff] [blame] | 958 | logit("%s", msg); |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 959 | } |
| 960 | } |
| 961 | |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 962 | xfree(ip); |
Darren Tucker | da34553 | 2006-07-10 23:04:19 +1000 | [diff] [blame] | 963 | xfree(host); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 964 | return 0; |
| 965 | |
| 966 | fail: |
| 967 | xfree(ip); |
Darren Tucker | da34553 | 2006-07-10 23:04:19 +1000 | [diff] [blame] | 968 | xfree(host); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 969 | return -1; |
| 970 | } |
| 971 | |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 972 | /* returns 0 if key verifies or -1 if key does NOT verify */ |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 973 | int |
| 974 | verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key) |
| 975 | { |
| 976 | struct stat st; |
Damien Miller | 150b557 | 2003-11-17 21:19:29 +1100 | [diff] [blame] | 977 | int flags = 0; |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 978 | |
Damien Miller | 150b557 | 2003-11-17 21:19:29 +1100 | [diff] [blame] | 979 | if (options.verify_host_key_dns && |
| 980 | verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) { |
| 981 | |
| 982 | if (flags & DNS_VERIFY_FOUND) { |
| 983 | |
| 984 | if (options.verify_host_key_dns == 1 && |
| 985 | flags & DNS_VERIFY_MATCH && |
| 986 | flags & DNS_VERIFY_SECURE) |
| 987 | return 0; |
| 988 | |
| 989 | if (flags & DNS_VERIFY_MATCH) { |
| 990 | matching_host_key_dns = 1; |
| 991 | } else { |
| 992 | warn_changed_key(host_key); |
| 993 | error("Update the SSHFP RR in DNS with the new " |
| 994 | "host key to get rid of this message."); |
| 995 | } |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 996 | } |
| 997 | } |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 998 | |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 999 | /* return ok if the key can be found in an old keyfile */ |
| 1000 | if (stat(options.system_hostfile2, &st) == 0 || |
| 1001 | stat(options.user_hostfile2, &st) == 0) { |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 1002 | if (check_host_key(host, hostaddr, options.port, host_key, |
| 1003 | RDONLY, options.user_hostfile2, |
| 1004 | options.system_hostfile2) == 0) |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1005 | return 0; |
| 1006 | } |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 1007 | return check_host_key(host, hostaddr, options.port, host_key, |
| 1008 | RDRW, options.user_hostfile, options.system_hostfile); |
Damien Miller | a34a28b | 1999-12-14 10:47:15 +1100 | [diff] [blame] | 1009 | } |
Damien Miller | 037a0dc | 1999-12-07 15:38:31 +1100 | [diff] [blame] | 1010 | |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1011 | /* |
| 1012 | * Starts a dialog with the server, and authenticates the current user on the |
| 1013 | * server. This does not need any extra privileges. The basic connection |
| 1014 | * to the server must already have been established before this is called. |
| 1015 | * If login fails, this function prints an error and never returns. |
| 1016 | * This function does not require super-user privileges. |
| 1017 | */ |
| 1018 | void |
Ben Lindstrom | 1bad256 | 2002-06-06 19:57:33 +0000 | [diff] [blame] | 1019 | ssh_login(Sensitive *sensitive, const char *orighost, |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 1020 | struct sockaddr *hostaddr, struct passwd *pw, int timeout_ms) |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1021 | { |
| 1022 | char *host, *cp; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 1023 | char *server_user, *local_user; |
| 1024 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 1025 | local_user = xstrdup(pw->pw_name); |
| 1026 | server_user = options.user ? options.user : local_user; |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1027 | |
| 1028 | /* Convert the user-supplied hostname into all lowercase. */ |
| 1029 | host = xstrdup(orighost); |
| 1030 | for (cp = host; *cp; cp++) |
| 1031 | if (isupper(*cp)) |
Damien Miller | 1d2b670 | 2006-03-26 14:09:54 +1100 | [diff] [blame] | 1032 | *cp = (char)tolower(*cp); |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1033 | |
| 1034 | /* Exchange protocol version identification strings with the server. */ |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 1035 | ssh_exchange_identification(timeout_ms); |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1036 | |
| 1037 | /* Put the connection into non-blocking mode. */ |
| 1038 | packet_set_nonblocking(); |
| 1039 | |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1040 | /* key exchange */ |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1041 | /* authenticate user */ |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 1042 | if (compat20) { |
| 1043 | ssh_kex2(host, hostaddr); |
Ben Lindstrom | 1bad256 | 2002-06-06 19:57:33 +0000 | [diff] [blame] | 1044 | ssh_userauth2(local_user, server_user, host, sensitive); |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 1045 | } else { |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 1046 | ssh_kex(host, hostaddr); |
Ben Lindstrom | 1bad256 | 2002-06-06 19:57:33 +0000 | [diff] [blame] | 1047 | ssh_userauth1(local_user, server_user, host, sensitive); |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 1048 | } |
Damien Miller | 40b5985 | 2006-06-13 13:00:25 +1000 | [diff] [blame] | 1049 | xfree(local_user); |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1050 | } |
Damien Miller | 79438cc | 2001-02-16 12:34:57 +1100 | [diff] [blame] | 1051 | |
| 1052 | void |
| 1053 | ssh_put_password(char *password) |
| 1054 | { |
| 1055 | int size; |
| 1056 | char *padded; |
| 1057 | |
Ben Lindstrom | d20d0f3 | 2001-03-10 17:22:20 +0000 | [diff] [blame] | 1058 | if (datafellows & SSH_BUG_PASSWORDPAD) { |
Ben Lindstrom | 664408d | 2001-06-09 01:42:01 +0000 | [diff] [blame] | 1059 | packet_put_cstring(password); |
Ben Lindstrom | d20d0f3 | 2001-03-10 17:22:20 +0000 | [diff] [blame] | 1060 | return; |
| 1061 | } |
Damien Miller | 79438cc | 2001-02-16 12:34:57 +1100 | [diff] [blame] | 1062 | size = roundup(strlen(password) + 1, 32); |
Damien Miller | 07d86be | 2006-03-26 14:19:21 +1100 | [diff] [blame] | 1063 | padded = xcalloc(1, size); |
Damien Miller | 79438cc | 2001-02-16 12:34:57 +1100 | [diff] [blame] | 1064 | strlcpy(padded, password, size); |
| 1065 | packet_put_string(padded, size); |
| 1066 | memset(padded, 0, size); |
| 1067 | xfree(padded); |
| 1068 | } |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1069 | |
| 1070 | static int |
| 1071 | show_key_from_file(const char *file, const char *host, int keytype) |
| 1072 | { |
| 1073 | Key *found; |
Darren Tucker | 9c16ac9 | 2008-06-13 04:40:35 +1000 | [diff] [blame] | 1074 | char *fp, *ra; |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1075 | int line, ret; |
| 1076 | |
| 1077 | found = key_new(keytype); |
| 1078 | if ((ret = lookup_key_in_hostfile_by_type(file, host, |
| 1079 | keytype, found, &line))) { |
| 1080 | fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX); |
Darren Tucker | 9c16ac9 | 2008-06-13 04:40:35 +1000 | [diff] [blame] | 1081 | ra = key_fingerprint(found, SSH_FP_MD5, SSH_FP_RANDOMART); |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 1082 | logit("WARNING: %s key found for host %s\n" |
Ben Lindstrom | 4b99be8 | 2002-08-01 01:26:29 +0000 | [diff] [blame] | 1083 | "in %s:%d\n" |
Darren Tucker | 9c16ac9 | 2008-06-13 04:40:35 +1000 | [diff] [blame] | 1084 | "%s key fingerprint %s.\n%s\n", |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1085 | key_type(found), host, file, line, |
Darren Tucker | 9c16ac9 | 2008-06-13 04:40:35 +1000 | [diff] [blame] | 1086 | key_type(found), fp, ra); |
| 1087 | xfree(ra); |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1088 | xfree(fp); |
| 1089 | } |
| 1090 | key_free(found); |
| 1091 | return (ret); |
| 1092 | } |
| 1093 | |
| 1094 | /* print all known host keys for a given host, but skip keys of given type */ |
| 1095 | static int |
| 1096 | show_other_keys(const char *host, Key *key) |
| 1097 | { |
| 1098 | int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1}; |
| 1099 | int i, found = 0; |
| 1100 | |
| 1101 | for (i = 0; type[i] != -1; i++) { |
| 1102 | if (type[i] == key->type) |
| 1103 | continue; |
| 1104 | if (type[i] != KEY_RSA1 && |
| 1105 | show_key_from_file(options.user_hostfile2, host, type[i])) { |
| 1106 | found = 1; |
| 1107 | continue; |
| 1108 | } |
| 1109 | if (type[i] != KEY_RSA1 && |
| 1110 | show_key_from_file(options.system_hostfile2, host, type[i])) { |
| 1111 | found = 1; |
| 1112 | continue; |
| 1113 | } |
| 1114 | if (show_key_from_file(options.user_hostfile, host, type[i])) { |
| 1115 | found = 1; |
| 1116 | continue; |
| 1117 | } |
| 1118 | if (show_key_from_file(options.system_hostfile, host, type[i])) { |
| 1119 | found = 1; |
| 1120 | continue; |
| 1121 | } |
| 1122 | debug2("no key of type %d for host %s", type[i], host); |
| 1123 | } |
| 1124 | return (found); |
| 1125 | } |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1126 | |
| 1127 | static void |
| 1128 | warn_changed_key(Key *host_key) |
| 1129 | { |
| 1130 | char *fp; |
Damien Miller | 8f746ec | 2003-11-17 21:11:15 +1100 | [diff] [blame] | 1131 | const char *type = key_type(host_key); |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1132 | |
| 1133 | fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); |
| 1134 | |
| 1135 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
| 1136 | error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @"); |
| 1137 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
| 1138 | error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!"); |
| 1139 | error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!"); |
| 1140 | error("It is also possible that the %s host key has just been changed.", type); |
| 1141 | error("The fingerprint for the %s key sent by the remote host is\n%s.", |
| 1142 | type, fp); |
| 1143 | error("Please contact your system administrator."); |
| 1144 | |
| 1145 | xfree(fp); |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1146 | } |
Damien Miller | d27b947 | 2005-12-13 19:29:02 +1100 | [diff] [blame] | 1147 | |
| 1148 | /* |
| 1149 | * Execute a local command |
| 1150 | */ |
| 1151 | int |
| 1152 | ssh_local_cmd(const char *args) |
| 1153 | { |
| 1154 | char *shell; |
| 1155 | pid_t pid; |
| 1156 | int status; |
| 1157 | |
| 1158 | if (!options.permit_local_command || |
| 1159 | args == NULL || !*args) |
| 1160 | return (1); |
| 1161 | |
| 1162 | if ((shell = getenv("SHELL")) == NULL) |
| 1163 | shell = _PATH_BSHELL; |
| 1164 | |
| 1165 | pid = fork(); |
| 1166 | if (pid == 0) { |
| 1167 | debug3("Executing %s -c \"%s\"", shell, args); |
| 1168 | execl(shell, shell, "-c", args, (char *)NULL); |
| 1169 | error("Couldn't execute %s -c \"%s\": %s", |
| 1170 | shell, args, strerror(errno)); |
| 1171 | _exit(1); |
| 1172 | } else if (pid == -1) |
| 1173 | fatal("fork failed: %.100s", strerror(errno)); |
| 1174 | while (waitpid(pid, &status, 0) == -1) |
| 1175 | if (errno != EINTR) |
| 1176 | fatal("Couldn't wait for child: %s", strerror(errno)); |
| 1177 | |
| 1178 | if (!WIFEXITED(status)) |
| 1179 | return (1); |
| 1180 | |
| 1181 | return (WEXITSTATUS(status)); |
| 1182 | } |