djm@openbsd.org | 5becbec | 2020-03-13 04:01:56 +0000 | [diff] [blame] | 1 | /* $OpenBSD: sshconnect.c,v 1.329 2020/03/13 04:01:56 djm 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 | |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 26 | #include <net/if.h> |
Damien Miller | 8ec8c3e | 2006-07-10 20:35:38 +1000 | [diff] [blame] | 27 | #include <netinet/in.h> |
Darren Tucker | 46aa3e0 | 2006-09-02 15:32:40 +1000 | [diff] [blame] | 28 | #include <arpa/inet.h> |
Damien Miller | 03e2003 | 2006-03-15 11:16:59 +1100 | [diff] [blame] | 29 | |
Damien Miller | c7b0636 | 2006-03-15 11:53:45 +1100 | [diff] [blame] | 30 | #include <ctype.h> |
Darren Tucker | 3997249 | 2006-07-12 22:22:46 +1000 | [diff] [blame] | 31 | #include <errno.h> |
Darren Tucker | 6e7fe1c | 2010-01-08 17:07:22 +1100 | [diff] [blame] | 32 | #include <fcntl.h> |
Damien Miller | b8fe89c | 2006-07-24 14:51:00 +1000 | [diff] [blame] | 33 | #include <netdb.h> |
Damien Miller | 6645e7a | 2006-03-15 14:42:54 +1100 | [diff] [blame] | 34 | #ifdef HAVE_PATHS_H |
Damien Miller | 03e2003 | 2006-03-15 11:16:59 +1100 | [diff] [blame] | 35 | #include <paths.h> |
Damien Miller | 6645e7a | 2006-03-15 14:42:54 +1100 | [diff] [blame] | 36 | #endif |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 37 | #include <pwd.h> |
djm@openbsd.org | 4540428 | 2017-06-24 05:37:44 +0000 | [diff] [blame] | 38 | #ifdef HAVE_POLL_H |
| 39 | #include <poll.h> |
| 40 | #endif |
Damien Miller | 9c0c31d | 2010-10-12 13:30:44 +1100 | [diff] [blame] | 41 | #include <signal.h> |
Damien Miller | a7a73ee | 2006-08-05 11:37:59 +1000 | [diff] [blame] | 42 | #include <stdio.h> |
Damien Miller | e7a1e5c | 2006-08-05 11:34:19 +1000 | [diff] [blame] | 43 | #include <stdlib.h> |
deraadt@openbsd.org | 72687c8 | 2019-11-13 04:47:52 +0000 | [diff] [blame] | 44 | #include <stdarg.h> |
Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame] | 45 | #include <string.h> |
Damien Miller | e6b3b61 | 2006-07-24 14:01:23 +1000 | [diff] [blame] | 46 | #include <unistd.h> |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 47 | #ifdef HAVE_IFADDRS_H |
| 48 | # include <ifaddrs.h> |
| 49 | #endif |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 50 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 51 | #include "xmalloc.h" |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 52 | #include "hostfile.h" |
| 53 | #include "ssh.h" |
markus@openbsd.org | cecee2d | 2018-07-09 21:03:30 +0000 | [diff] [blame] | 54 | #include "sshbuf.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 55 | #include "packet.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 56 | #include "compat.h" |
markus@openbsd.org | 5467fbc | 2018-07-11 18:53:29 +0000 | [diff] [blame] | 57 | #include "sshkey.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 58 | #include "sshconnect.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 59 | #include "log.h" |
Damien Miller | 7acefbb | 2014-07-18 14:11:24 +1000 | [diff] [blame] | 60 | #include "misc.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 61 | #include "readconf.h" |
| 62 | #include "atomicio.h" |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 63 | #include "dns.h" |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 64 | #include "monitor_fdpass.h" |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 65 | #include "ssh2.h" |
Damien Miller | b757677 | 2006-07-10 20:23:39 +1000 | [diff] [blame] | 66 | #include "version.h" |
djm@openbsd.org | 5e39a49 | 2014-12-04 02:24:32 +0000 | [diff] [blame] | 67 | #include "authfile.h" |
| 68 | #include "ssherr.h" |
jcs@openbsd.org | f361df4 | 2015-11-15 22:26:49 +0000 | [diff] [blame] | 69 | #include "authfd.h" |
djm@openbsd.org | 0a843d9 | 2018-12-27 03:25:24 +0000 | [diff] [blame] | 70 | #include "kex.h" |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 71 | |
markus@openbsd.org | 54d90ac | 2017-05-30 08:52:19 +0000 | [diff] [blame] | 72 | struct sshkey *previous_host_key = NULL; |
Damien Miller | 1383bd8 | 2000-04-06 12:32:37 +1000 | [diff] [blame] | 73 | |
Damien Miller | c1af1d5 | 2005-11-05 15:08:57 +1100 | [diff] [blame] | 74 | static int matching_host_key_dns = 0; |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 75 | |
Damien Miller | a41ccca | 2010-10-07 22:07:32 +1100 | [diff] [blame] | 76 | static pid_t proxy_command_pid = 0; |
| 77 | |
Ben Lindstrom | f9c4884 | 2002-06-11 16:37:51 +0000 | [diff] [blame] | 78 | /* import */ |
djm@openbsd.org | ccef7c4 | 2018-11-16 06:17:38 +0000 | [diff] [blame] | 79 | extern int debug_flag; |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 80 | extern Options options; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 81 | extern char *__progname; |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 82 | |
markus@openbsd.org | 54d90ac | 2017-05-30 08:52:19 +0000 | [diff] [blame] | 83 | static int show_other_keys(struct hostkeys *, struct sshkey *); |
| 84 | static void warn_changed_key(struct sshkey *); |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 85 | |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 86 | /* Expand a proxy command */ |
| 87 | static char * |
| 88 | expand_proxy_command(const char *proxy_command, const char *user, |
naddy@openbsd.org | b8a4ca2 | 2020-01-11 16:23:10 +0000 | [diff] [blame] | 89 | const char *host, const char *host_arg, int port) |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 90 | { |
| 91 | char *tmp, *ret, strport[NI_MAXSERV]; |
| 92 | |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 93 | snprintf(strport, sizeof strport, "%d", port); |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 94 | xasprintf(&tmp, "exec %s", proxy_command); |
djm@openbsd.org | fbe24b1 | 2019-09-13 04:27:35 +0000 | [diff] [blame] | 95 | ret = percent_expand(tmp, |
| 96 | "h", host, |
| 97 | "n", host_arg, |
| 98 | "p", strport, |
| 99 | "r", options.user, |
| 100 | (char *)NULL); |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 101 | free(tmp); |
| 102 | return ret; |
| 103 | } |
| 104 | |
djm@openbsd.org | ccef7c4 | 2018-11-16 06:17:38 +0000 | [diff] [blame] | 105 | static void |
| 106 | stderr_null(void) |
| 107 | { |
| 108 | int devnull; |
| 109 | |
| 110 | if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1) { |
| 111 | error("Can't open %s for stderr redirection: %s", |
| 112 | _PATH_DEVNULL, strerror(errno)); |
| 113 | return; |
| 114 | } |
| 115 | if (devnull == STDERR_FILENO) |
| 116 | return; |
| 117 | if (dup2(devnull, STDERR_FILENO) == -1) |
| 118 | error("Cannot redirect stderr to %s", _PATH_DEVNULL); |
| 119 | if (devnull > STDERR_FILENO) |
| 120 | close(devnull); |
| 121 | } |
| 122 | |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 123 | /* |
| 124 | * Connect to the given ssh server using a proxy command that passes a |
| 125 | * a connected fd back to us. |
| 126 | */ |
| 127 | static int |
djm@openbsd.org | fbe24b1 | 2019-09-13 04:27:35 +0000 | [diff] [blame] | 128 | ssh_proxy_fdpass_connect(struct ssh *ssh, const char *host, |
| 129 | const char *host_arg, u_short port, const char *proxy_command) |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 130 | { |
| 131 | char *command_string; |
| 132 | int sp[2], sock; |
| 133 | pid_t pid; |
| 134 | char *shell; |
| 135 | |
| 136 | if ((shell = getenv("SHELL")) == NULL) |
| 137 | shell = _PATH_BSHELL; |
| 138 | |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 139 | if (socketpair(AF_UNIX, SOCK_STREAM, 0, sp) == -1) |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 140 | fatal("Could not create socketpair to communicate with " |
| 141 | "proxy dialer: %.100s", strerror(errno)); |
| 142 | |
| 143 | command_string = expand_proxy_command(proxy_command, options.user, |
naddy@openbsd.org | b8a4ca2 | 2020-01-11 16:23:10 +0000 | [diff] [blame] | 144 | host, host_arg, port); |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 145 | debug("Executing proxy dialer command: %.500s", command_string); |
| 146 | |
| 147 | /* Fork and execute the proxy command. */ |
| 148 | if ((pid = fork()) == 0) { |
| 149 | char *argv[10]; |
| 150 | |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 151 | close(sp[1]); |
| 152 | /* Redirect stdin and stdout. */ |
| 153 | if (sp[0] != 0) { |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 154 | if (dup2(sp[0], 0) == -1) |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 155 | perror("dup2 stdin"); |
| 156 | } |
| 157 | if (sp[0] != 1) { |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 158 | if (dup2(sp[0], 1) == -1) |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 159 | perror("dup2 stdout"); |
| 160 | } |
| 161 | if (sp[0] >= 2) |
| 162 | close(sp[0]); |
| 163 | |
| 164 | /* |
djm@openbsd.org | ccef7c4 | 2018-11-16 06:17:38 +0000 | [diff] [blame] | 165 | * Stderr is left for non-ControlPersist connections is so |
| 166 | * error messages may be printed on the user's terminal. |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 167 | */ |
dtucker@openbsd.org | 7fca94e | 2018-11-18 22:43:29 +0000 | [diff] [blame] | 168 | if (!debug_flag && options.control_path != NULL && |
| 169 | options.control_persist) |
djm@openbsd.org | ccef7c4 | 2018-11-16 06:17:38 +0000 | [diff] [blame] | 170 | stderr_null(); |
| 171 | |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 172 | argv[0] = shell; |
| 173 | argv[1] = "-c"; |
| 174 | argv[2] = command_string; |
| 175 | argv[3] = NULL; |
| 176 | |
| 177 | /* |
| 178 | * Execute the proxy command. |
| 179 | * Note that we gave up any extra privileges above. |
| 180 | */ |
| 181 | execv(argv[0], argv); |
| 182 | perror(argv[0]); |
| 183 | exit(1); |
| 184 | } |
| 185 | /* Parent. */ |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 186 | if (pid == -1) |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 187 | fatal("fork failed: %.100s", strerror(errno)); |
| 188 | close(sp[0]); |
| 189 | free(command_string); |
| 190 | |
| 191 | if ((sock = mm_receive_fd(sp[1])) == -1) |
| 192 | fatal("proxy dialer did not pass back a connection"); |
markus@openbsd.org | fc77ccd | 2016-01-14 22:56:56 +0000 | [diff] [blame] | 193 | close(sp[1]); |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 194 | |
| 195 | while (waitpid(pid, NULL, 0) == -1) |
| 196 | if (errno != EINTR) |
| 197 | fatal("Couldn't wait for child: %s", strerror(errno)); |
| 198 | |
| 199 | /* Set the connection file descriptors. */ |
djm@openbsd.org | dbee411 | 2017-09-12 06:32:07 +0000 | [diff] [blame] | 200 | if (ssh_packet_set_connection(ssh, sock, sock) == NULL) |
| 201 | return -1; /* ssh_packet_set_connection logs error */ |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 202 | |
| 203 | return 0; |
| 204 | } |
| 205 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 206 | /* |
| 207 | * Connect to the given ssh server using a proxy command. |
| 208 | */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 209 | static int |
djm@openbsd.org | fbe24b1 | 2019-09-13 04:27:35 +0000 | [diff] [blame] | 210 | ssh_proxy_connect(struct ssh *ssh, const char *host, const char *host_arg, |
| 211 | u_short port, const char *proxy_command) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 212 | { |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 213 | char *command_string; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 214 | int pin[2], pout[2]; |
Damien Miller | 166fca8 | 2000-04-20 07:42:21 +1000 | [diff] [blame] | 215 | pid_t pid; |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 216 | char *shell; |
Damien Miller | 1d824ab | 2007-09-17 11:58:04 +1000 | [diff] [blame] | 217 | |
Damien Miller | 38d9a96 | 2010-10-07 22:07:11 +1100 | [diff] [blame] | 218 | if ((shell = getenv("SHELL")) == NULL || *shell == '\0') |
Damien Miller | 1d824ab | 2007-09-17 11:58:04 +1000 | [diff] [blame] | 219 | shell = _PATH_BSHELL; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 220 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 221 | /* Create pipes for communicating with the proxy. */ |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 222 | if (pipe(pin) == -1 || pipe(pout) == -1) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 223 | fatal("Could not create pipes to communicate with the proxy: %.100s", |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 224 | strerror(errno)); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 225 | |
Damien Miller | 1262b66 | 2013-08-21 02:44:24 +1000 | [diff] [blame] | 226 | command_string = expand_proxy_command(proxy_command, options.user, |
naddy@openbsd.org | b8a4ca2 | 2020-01-11 16:23:10 +0000 | [diff] [blame] | 227 | host, host_arg, port); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 228 | debug("Executing proxy command: %.500s", command_string); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 229 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 230 | /* Fork and execute the proxy command. */ |
| 231 | if ((pid = fork()) == 0) { |
| 232 | char *argv[10]; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 233 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 234 | /* Redirect stdin and stdout. */ |
| 235 | close(pin[1]); |
| 236 | if (pin[0] != 0) { |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 237 | if (dup2(pin[0], 0) == -1) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 238 | perror("dup2 stdin"); |
| 239 | close(pin[0]); |
| 240 | } |
| 241 | close(pout[0]); |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 242 | if (dup2(pout[1], 1) == -1) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 243 | perror("dup2 stdout"); |
| 244 | /* Cannot be 1 because pin allocated two descriptors. */ |
| 245 | close(pout[1]); |
| 246 | |
djm@openbsd.org | ccef7c4 | 2018-11-16 06:17:38 +0000 | [diff] [blame] | 247 | /* |
| 248 | * Stderr is left for non-ControlPersist connections is so |
| 249 | * error messages may be printed on the user's terminal. |
| 250 | */ |
dtucker@openbsd.org | 7fca94e | 2018-11-18 22:43:29 +0000 | [diff] [blame] | 251 | if (!debug_flag && options.control_path != NULL && |
| 252 | options.control_persist) |
djm@openbsd.org | ccef7c4 | 2018-11-16 06:17:38 +0000 | [diff] [blame] | 253 | stderr_null(); |
| 254 | |
Damien Miller | 1d824ab | 2007-09-17 11:58:04 +1000 | [diff] [blame] | 255 | argv[0] = shell; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 256 | argv[1] = "-c"; |
| 257 | argv[2] = command_string; |
| 258 | argv[3] = NULL; |
| 259 | |
| 260 | /* Execute the proxy command. Note that we gave up any |
| 261 | extra privileges above. */ |
dtucker@openbsd.org | 3bf2a6a | 2020-01-23 07:10:22 +0000 | [diff] [blame] | 262 | ssh_signal(SIGPIPE, SIG_DFL); |
Kevin Steves | fcd5d60 | 2001-01-07 11:45:22 +0000 | [diff] [blame] | 263 | execv(argv[0], argv); |
| 264 | perror(argv[0]); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 265 | exit(1); |
| 266 | } |
| 267 | /* Parent. */ |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 268 | if (pid == -1) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 269 | fatal("fork failed: %.100s", strerror(errno)); |
Damien Miller | 8c4e18a | 2002-09-19 12:05:02 +1000 | [diff] [blame] | 270 | else |
| 271 | proxy_command_pid = pid; /* save pid to clean up later */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 272 | |
| 273 | /* Close child side of the descriptors. */ |
| 274 | close(pin[0]); |
| 275 | close(pout[1]); |
| 276 | |
| 277 | /* Free the command name. */ |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 278 | free(command_string); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 279 | |
| 280 | /* Set the connection file descriptors. */ |
djm@openbsd.org | dbee411 | 2017-09-12 06:32:07 +0000 | [diff] [blame] | 281 | if (ssh_packet_set_connection(ssh, pout[0], pin[1]) == NULL) |
| 282 | return -1; /* ssh_packet_set_connection logs error */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 283 | |
Ben Lindstrom | f9cedb9 | 2001-08-06 21:07:11 +0000 | [diff] [blame] | 284 | return 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 285 | } |
| 286 | |
Damien Miller | a41ccca | 2010-10-07 22:07:32 +1100 | [diff] [blame] | 287 | void |
| 288 | ssh_kill_proxy_command(void) |
| 289 | { |
| 290 | /* |
| 291 | * Send SIGHUP to proxy command if used. We don't wait() in |
| 292 | * case it hangs and instead rely on init to reap the child |
| 293 | */ |
| 294 | if (proxy_command_pid > 1) |
Damien Miller | 45fcdaa | 2010-10-07 22:07:58 +1100 | [diff] [blame] | 295 | kill(proxy_command_pid, SIGHUP); |
Damien Miller | a41ccca | 2010-10-07 22:07:32 +1100 | [diff] [blame] | 296 | } |
| 297 | |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 298 | #ifdef HAVE_IFADDRS_H |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 299 | /* |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 300 | * Search a interface address list (returned from getifaddrs(3)) for an |
djm@openbsd.org | 001aa55 | 2018-04-10 00:10:49 +0000 | [diff] [blame] | 301 | * address that matches the desired address family on the specified interface. |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 302 | * Returns 0 and fills in *resultp and *rlenp on success. Returns -1 on failure. |
| 303 | */ |
| 304 | static int |
| 305 | check_ifaddrs(const char *ifname, int af, const struct ifaddrs *ifaddrs, |
| 306 | struct sockaddr_storage *resultp, socklen_t *rlenp) |
| 307 | { |
| 308 | struct sockaddr_in6 *sa6; |
| 309 | struct sockaddr_in *sa; |
| 310 | struct in6_addr *v6addr; |
| 311 | const struct ifaddrs *ifa; |
| 312 | int allow_local; |
| 313 | |
| 314 | /* |
| 315 | * Prefer addresses that are not loopback or linklocal, but use them |
| 316 | * if nothing else matches. |
| 317 | */ |
| 318 | for (allow_local = 0; allow_local < 2; allow_local++) { |
| 319 | for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) { |
| 320 | if (ifa->ifa_addr == NULL || ifa->ifa_name == NULL || |
| 321 | (ifa->ifa_flags & IFF_UP) == 0 || |
| 322 | ifa->ifa_addr->sa_family != af || |
| 323 | strcmp(ifa->ifa_name, options.bind_interface) != 0) |
| 324 | continue; |
| 325 | switch (ifa->ifa_addr->sa_family) { |
| 326 | case AF_INET: |
| 327 | sa = (struct sockaddr_in *)ifa->ifa_addr; |
| 328 | if (!allow_local && sa->sin_addr.s_addr == |
| 329 | htonl(INADDR_LOOPBACK)) |
| 330 | continue; |
| 331 | if (*rlenp < sizeof(struct sockaddr_in)) { |
| 332 | error("%s: v4 addr doesn't fit", |
| 333 | __func__); |
| 334 | return -1; |
| 335 | } |
| 336 | *rlenp = sizeof(struct sockaddr_in); |
| 337 | memcpy(resultp, sa, *rlenp); |
| 338 | return 0; |
| 339 | case AF_INET6: |
| 340 | sa6 = (struct sockaddr_in6 *)ifa->ifa_addr; |
| 341 | v6addr = &sa6->sin6_addr; |
| 342 | if (!allow_local && |
| 343 | (IN6_IS_ADDR_LINKLOCAL(v6addr) || |
| 344 | IN6_IS_ADDR_LOOPBACK(v6addr))) |
| 345 | continue; |
| 346 | if (*rlenp < sizeof(struct sockaddr_in6)) { |
| 347 | error("%s: v6 addr doesn't fit", |
| 348 | __func__); |
| 349 | return -1; |
| 350 | } |
| 351 | *rlenp = sizeof(struct sockaddr_in6); |
| 352 | memcpy(resultp, sa6, *rlenp); |
| 353 | return 0; |
| 354 | } |
| 355 | } |
| 356 | } |
| 357 | return -1; |
| 358 | } |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 359 | #endif |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 360 | |
| 361 | /* |
dtucker@openbsd.org | 3ba6e68 | 2018-07-19 23:03:16 +0000 | [diff] [blame] | 362 | * Creates a socket for use as the ssh connection. |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 363 | */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 364 | static int |
dtucker@openbsd.org | 95d41e9 | 2018-07-19 10:28:47 +0000 | [diff] [blame] | 365 | ssh_create_socket(struct addrinfo *ai) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 366 | { |
dtucker@openbsd.org | 258dc8b | 2018-07-18 11:34:04 +0000 | [diff] [blame] | 367 | int sock, r; |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 368 | struct sockaddr_storage bindaddr; |
| 369 | socklen_t bindaddrlen = 0; |
Damien Miller | d1a7a9c | 2014-02-07 09:24:33 +1100 | [diff] [blame] | 370 | struct addrinfo hints, *res = NULL; |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 371 | #ifdef HAVE_IFADDRS_H |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 372 | struct ifaddrs *ifaddrs = NULL; |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 373 | #endif |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 374 | char ntop[NI_MAXHOST]; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 375 | |
Darren Tucker | 7bd98e7 | 2010-01-10 10:31:12 +1100 | [diff] [blame] | 376 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 377 | if (sock == -1) { |
Darren Tucker | e6e52f8 | 2013-10-10 10:28:07 +1100 | [diff] [blame] | 378 | error("socket: %s", strerror(errno)); |
Darren Tucker | 6e7fe1c | 2010-01-08 17:07:22 +1100 | [diff] [blame] | 379 | return -1; |
| 380 | } |
| 381 | fcntl(sock, F_SETFD, FD_CLOEXEC); |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 382 | |
| 383 | /* Bind the socket to an alternative local IP address */ |
dtucker@openbsd.org | 95d41e9 | 2018-07-19 10:28:47 +0000 | [diff] [blame] | 384 | if (options.bind_address == NULL && options.bind_interface == NULL) |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 385 | return sock; |
| 386 | |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 387 | if (options.bind_address != NULL) { |
Damien Miller | d1a7a9c | 2014-02-07 09:24:33 +1100 | [diff] [blame] | 388 | memset(&hints, 0, sizeof(hints)); |
| 389 | hints.ai_family = ai->ai_family; |
| 390 | hints.ai_socktype = ai->ai_socktype; |
| 391 | hints.ai_protocol = ai->ai_protocol; |
| 392 | hints.ai_flags = AI_PASSIVE; |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 393 | if ((r = getaddrinfo(options.bind_address, NULL, |
| 394 | &hints, &res)) != 0) { |
Damien Miller | d1a7a9c | 2014-02-07 09:24:33 +1100 | [diff] [blame] | 395 | error("getaddrinfo: %s: %s", options.bind_address, |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 396 | ssh_gai_strerror(r)); |
| 397 | goto fail; |
Damien Miller | d1a7a9c | 2014-02-07 09:24:33 +1100 | [diff] [blame] | 398 | } |
dtucker@openbsd.org | 3e19fb9 | 2018-02-23 04:18:46 +0000 | [diff] [blame] | 399 | if (res == NULL) { |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 400 | error("getaddrinfo: no addrs"); |
| 401 | goto fail; |
dtucker@openbsd.org | 3e19fb9 | 2018-02-23 04:18:46 +0000 | [diff] [blame] | 402 | } |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 403 | memcpy(&bindaddr, res->ai_addr, res->ai_addrlen); |
| 404 | bindaddrlen = res->ai_addrlen; |
| 405 | } else if (options.bind_interface != NULL) { |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 406 | #ifdef HAVE_IFADDRS_H |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 407 | if ((r = getifaddrs(&ifaddrs)) != 0) { |
| 408 | error("getifaddrs: %s: %s", options.bind_interface, |
| 409 | strerror(errno)); |
| 410 | goto fail; |
| 411 | } |
| 412 | bindaddrlen = sizeof(bindaddr); |
| 413 | if (check_ifaddrs(options.bind_interface, ai->ai_family, |
| 414 | ifaddrs, &bindaddr, &bindaddrlen) != 0) { |
| 415 | logit("getifaddrs: %s: no suitable addresses", |
| 416 | options.bind_interface); |
| 417 | goto fail; |
| 418 | } |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 419 | #else |
| 420 | error("BindInterface not supported on this platform."); |
| 421 | #endif |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 422 | } |
| 423 | if ((r = getnameinfo((struct sockaddr *)&bindaddr, bindaddrlen, |
| 424 | ntop, sizeof(ntop), NULL, 0, NI_NUMERICHOST)) != 0) { |
| 425 | error("%s: getnameinfo failed: %s", __func__, |
| 426 | ssh_gai_strerror(r)); |
| 427 | goto fail; |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 428 | } |
dtucker@openbsd.org | 258dc8b | 2018-07-18 11:34:04 +0000 | [diff] [blame] | 429 | if (bind(sock, (struct sockaddr *)&bindaddr, bindaddrlen) != 0) { |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 430 | error("bind %s: %s", ntop, strerror(errno)); |
| 431 | goto fail; |
Ben Lindstrom | e0f8804 | 2001-04-30 13:06:24 +0000 | [diff] [blame] | 432 | } |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 433 | debug("%s: bound to %s", __func__, ntop); |
| 434 | /* success */ |
| 435 | goto out; |
| 436 | fail: |
| 437 | close(sock); |
| 438 | sock = -1; |
| 439 | out: |
Damien Miller | d1a7a9c | 2014-02-07 09:24:33 +1100 | [diff] [blame] | 440 | if (res != NULL) |
| 441 | freeaddrinfo(res); |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 442 | #ifdef HAVE_IFADDRS_H |
djm@openbsd.org | ac2e302 | 2018-02-23 02:34:33 +0000 | [diff] [blame] | 443 | if (ifaddrs != NULL) |
| 444 | freeifaddrs(ifaddrs); |
Darren Tucker | b59162d | 2018-02-23 15:20:42 +1100 | [diff] [blame] | 445 | #endif |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 446 | return sock; |
| 447 | } |
| 448 | |
djm@openbsd.org | 4540428 | 2017-06-24 05:37:44 +0000 | [diff] [blame] | 449 | /* |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 450 | * Opens a TCP/IP connection to the remote server on the given host. |
| 451 | * The address of the remote host will be returned in hostaddr. |
dtucker@openbsd.org | 95d41e9 | 2018-07-19 10:28:47 +0000 | [diff] [blame] | 452 | * If port is 0, the default port will be used. |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 453 | * Connection_attempts specifies the maximum number of tries (one per |
| 454 | * second). If proxy_command is non-NULL, it specifies the command (with %h |
| 455 | * and %p substituted for host and port, respectively) to use to contact |
| 456 | * the daemon. |
| 457 | */ |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 458 | static int |
djm@openbsd.org | dbee411 | 2017-09-12 06:32:07 +0000 | [diff] [blame] | 459 | ssh_connect_direct(struct ssh *ssh, const char *host, struct addrinfo *aitop, |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 460 | struct sockaddr_storage *hostaddr, u_short port, int family, |
dtucker@openbsd.org | 95d41e9 | 2018-07-19 10:28:47 +0000 | [diff] [blame] | 461 | int connection_attempts, int *timeout_ms, int want_keepalive) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 462 | { |
dtucker@openbsd.org | 483b3b6 | 2019-02-01 03:52:23 +0000 | [diff] [blame] | 463 | int on = 1, saved_timeout_ms = *timeout_ms; |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 464 | int oerrno, sock = -1, attempt; |
Ben Lindstrom | bf555ba | 2001-01-18 02:04:35 +0000 | [diff] [blame] | 465 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 466 | struct addrinfo *ai; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 467 | |
dtucker@openbsd.org | 95d41e9 | 2018-07-19 10:28:47 +0000 | [diff] [blame] | 468 | debug2("%s", __func__); |
djm@openbsd.org | 88b6fcd | 2015-11-19 08:23:27 +0000 | [diff] [blame] | 469 | memset(ntop, 0, sizeof(ntop)); |
| 470 | memset(strport, 0, sizeof(strport)); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 471 | |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 472 | for (attempt = 0; attempt < connection_attempts; attempt++) { |
Damien Miller | f4bcd10 | 2006-10-24 03:02:23 +1000 | [diff] [blame] | 473 | if (attempt > 0) { |
| 474 | /* Sleep a moment before retrying. */ |
| 475 | sleep(1); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 476 | debug("Trying again..."); |
Damien Miller | f4bcd10 | 2006-10-24 03:02:23 +1000 | [diff] [blame] | 477 | } |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 478 | /* |
| 479 | * Loop through addresses for this host, and try each one in |
| 480 | * sequence until the connection succeeds. |
| 481 | */ |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 482 | for (ai = aitop; ai; ai = ai->ai_next) { |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 483 | if (ai->ai_family != AF_INET && |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 484 | ai->ai_family != AF_INET6) { |
| 485 | errno = EAFNOSUPPORT; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 486 | continue; |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 487 | } |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 488 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, |
| 489 | ntop, sizeof(ntop), strport, sizeof(strport), |
| 490 | NI_NUMERICHOST|NI_NUMERICSERV) != 0) { |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 491 | oerrno = errno; |
djm@openbsd.org | 46152af | 2015-09-04 04:55:24 +0000 | [diff] [blame] | 492 | error("%s: getnameinfo failed", __func__); |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 493 | errno = oerrno; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 494 | continue; |
| 495 | } |
| 496 | debug("Connecting to %.200s [%.100s] port %s.", |
| 497 | host, ntop, strport); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 498 | |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 499 | /* Create a socket for connecting. */ |
dtucker@openbsd.org | 95d41e9 | 2018-07-19 10:28:47 +0000 | [diff] [blame] | 500 | sock = ssh_create_socket(ai); |
stsp@openbsd.org | a60c5dc | 2018-01-23 18:33:49 +0000 | [diff] [blame] | 501 | if (sock < 0) { |
Ben Lindstrom | f9cedb9 | 2001-08-06 21:07:11 +0000 | [diff] [blame] | 502 | /* Any error is already output */ |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 503 | errno = 0; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 504 | continue; |
stsp@openbsd.org | a60c5dc | 2018-01-23 18:33:49 +0000 | [diff] [blame] | 505 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 506 | |
dtucker@openbsd.org | 483b3b6 | 2019-02-01 03:52:23 +0000 | [diff] [blame] | 507 | *timeout_ms = saved_timeout_ms; |
Damien Miller | b78d5eb | 2003-05-16 11:39:04 +1000 | [diff] [blame] | 508 | if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen, |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 509 | timeout_ms) >= 0) { |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 510 | /* Successful connection. */ |
Ben Lindstrom | a370005 | 2001-04-05 23:26:32 +0000 | [diff] [blame] | 511 | memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 512 | break; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 513 | } else { |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 514 | oerrno = errno; |
Ben Lindstrom | 728aa7e | 2002-07-15 17:48:11 +0000 | [diff] [blame] | 515 | debug("connect to address %s port %s: %s", |
| 516 | ntop, strport, strerror(errno)); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 517 | close(sock); |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 518 | sock = -1; |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 519 | errno = oerrno; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 520 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 521 | } |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 522 | if (sock != -1) |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 523 | break; /* Successful connection. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 524 | } |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 525 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 526 | /* Return failure if we didn't get a successful connection. */ |
Damien Miller | 56e5e6a | 2006-04-23 12:08:59 +1000 | [diff] [blame] | 527 | if (sock == -1) { |
Darren Tucker | b2161e3 | 2005-01-20 11:00:46 +1100 | [diff] [blame] | 528 | error("ssh: connect to host %s port %s: %s", |
djm@openbsd.org | 7c77991 | 2018-01-23 05:17:04 +0000 | [diff] [blame] | 529 | host, strport, errno == 0 ? "failure" : strerror(errno)); |
| 530 | return -1; |
Ben Lindstrom | a6cd75c | 2002-07-11 04:00:19 +0000 | [diff] [blame] | 531 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 532 | |
| 533 | debug("Connection established."); |
| 534 | |
Damien Miller | 12c150e | 2003-12-17 16:31:10 +1100 | [diff] [blame] | 535 | /* Set SO_KEEPALIVE if requested. */ |
Damien Miller | 67bd062 | 2007-09-17 12:06:57 +1000 | [diff] [blame] | 536 | if (want_keepalive && |
Ben Lindstrom | bf555ba | 2001-01-18 02:04:35 +0000 | [diff] [blame] | 537 | setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 538 | sizeof(on)) == -1) |
Ben Lindstrom | bf555ba | 2001-01-18 02:04:35 +0000 | [diff] [blame] | 539 | error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 540 | |
| 541 | /* Set the connection. */ |
djm@openbsd.org | dbee411 | 2017-09-12 06:32:07 +0000 | [diff] [blame] | 542 | if (ssh_packet_set_connection(ssh, sock, sock) == NULL) |
| 543 | return -1; /* ssh_packet_set_connection logs error */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 544 | |
djm@openbsd.org | 2aefdf1 | 2019-09-13 04:31:19 +0000 | [diff] [blame] | 545 | return 0; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 546 | } |
| 547 | |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 548 | int |
djm@openbsd.org | fbe24b1 | 2019-09-13 04:27:35 +0000 | [diff] [blame] | 549 | ssh_connect(struct ssh *ssh, const char *host, const char *host_arg, |
| 550 | struct addrinfo *addrs, struct sockaddr_storage *hostaddr, u_short port, |
| 551 | int family, int connection_attempts, int *timeout_ms, int want_keepalive) |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 552 | { |
markus@openbsd.org | 8e7bac3 | 2019-02-27 19:37:01 +0000 | [diff] [blame] | 553 | int in, out; |
| 554 | |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 555 | if (options.proxy_command == NULL) { |
djm@openbsd.org | dbee411 | 2017-09-12 06:32:07 +0000 | [diff] [blame] | 556 | return ssh_connect_direct(ssh, host, addrs, hostaddr, port, |
dtucker@openbsd.org | 95d41e9 | 2018-07-19 10:28:47 +0000 | [diff] [blame] | 557 | family, connection_attempts, timeout_ms, want_keepalive); |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 558 | } else if (strcmp(options.proxy_command, "-") == 0) { |
deraadt@openbsd.org | 4d28fa7 | 2019-06-28 13:35:04 +0000 | [diff] [blame] | 559 | if ((in = dup(STDIN_FILENO)) == -1 || |
| 560 | (out = dup(STDOUT_FILENO)) == -1) { |
markus@openbsd.org | 8e7bac3 | 2019-02-27 19:37:01 +0000 | [diff] [blame] | 561 | if (in >= 0) |
| 562 | close(in); |
| 563 | error("%s: dup() in/out failed", __func__); |
| 564 | return -1; /* ssh_packet_set_connection logs error */ |
| 565 | } |
| 566 | if ((ssh_packet_set_connection(ssh, in, out)) == NULL) |
djm@openbsd.org | dbee411 | 2017-09-12 06:32:07 +0000 | [diff] [blame] | 567 | return -1; /* ssh_packet_set_connection logs error */ |
| 568 | return 0; |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 569 | } else if (options.proxy_use_fdpass) { |
djm@openbsd.org | fbe24b1 | 2019-09-13 04:27:35 +0000 | [diff] [blame] | 570 | return ssh_proxy_fdpass_connect(ssh, host, host_arg, port, |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 571 | options.proxy_command); |
| 572 | } |
djm@openbsd.org | fbe24b1 | 2019-09-13 04:27:35 +0000 | [diff] [blame] | 573 | return ssh_proxy_connect(ssh, host, host_arg, port, |
| 574 | options.proxy_command); |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 575 | } |
| 576 | |
Ben Lindstrom | b6c06d9 | 2001-02-10 23:21:09 +0000 | [diff] [blame] | 577 | /* defaults to 'no' */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 578 | static int |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 579 | confirm(const char *prompt, const char *fingerprint) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 580 | { |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 581 | const char *msg, *again = "Please type 'yes' or 'no': "; |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 582 | const char *again_fp = "Please type 'yes', 'no' or the fingerprint: "; |
dtucker@openbsd.org | 65cf873 | 2020-01-22 07:38:30 +0000 | [diff] [blame] | 583 | char *p, *cp; |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 584 | int ret = -1; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 585 | |
Ben Lindstrom | b6c06d9 | 2001-02-10 23:21:09 +0000 | [diff] [blame] | 586 | if (options.batch_mode) |
| 587 | return 0; |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 588 | for (msg = prompt;;msg = fingerprint ? again_fp : again) { |
dtucker@openbsd.org | 65cf873 | 2020-01-22 07:38:30 +0000 | [diff] [blame] | 589 | cp = p = read_passphrase(msg, RP_ECHO); |
djm@openbsd.org | e0ce54c | 2017-12-06 05:06:21 +0000 | [diff] [blame] | 590 | if (p == NULL) |
| 591 | return 0; |
dtucker@openbsd.org | 65cf873 | 2020-01-22 07:38:30 +0000 | [diff] [blame] | 592 | p += strspn(p, " \t"); /* skip leading whitespace */ |
| 593 | p[strcspn(p, " \t\n")] = '\0'; /* remove trailing whitespace */ |
djm@openbsd.org | e0ce54c | 2017-12-06 05:06:21 +0000 | [diff] [blame] | 594 | if (p[0] == '\0' || strcasecmp(p, "no") == 0) |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 595 | ret = 0; |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 596 | else if (strcasecmp(p, "yes") == 0 || (fingerprint != NULL && |
| 597 | strcasecmp(p, fingerprint) == 0)) |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 598 | ret = 1; |
dtucker@openbsd.org | 65cf873 | 2020-01-22 07:38:30 +0000 | [diff] [blame] | 599 | free(cp); |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 600 | if (ret != -1) |
| 601 | return ret; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 602 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 603 | } |
| 604 | |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 605 | static int |
djm@openbsd.org | ecac7e1 | 2018-09-20 03:30:44 +0000 | [diff] [blame] | 606 | check_host_cert(const char *host, const struct sshkey *key) |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 607 | { |
| 608 | const char *reason; |
djm@openbsd.org | ecac7e1 | 2018-09-20 03:30:44 +0000 | [diff] [blame] | 609 | int r; |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 610 | |
djm@openbsd.org | ecac7e1 | 2018-09-20 03:30:44 +0000 | [diff] [blame] | 611 | if (sshkey_cert_check_authority(key, 1, 0, host, &reason) != 0) { |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 612 | error("%s", reason); |
| 613 | return 0; |
| 614 | } |
djm@openbsd.org | ecac7e1 | 2018-09-20 03:30:44 +0000 | [diff] [blame] | 615 | if (sshbuf_len(key->cert->critical) != 0) { |
Damien Miller | 4e270b0 | 2010-04-16 15:56:21 +1000 | [diff] [blame] | 616 | error("Certificate for %s contains unsupported " |
| 617 | "critical options(s)", host); |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 618 | return 0; |
| 619 | } |
djm@openbsd.org | ecac7e1 | 2018-09-20 03:30:44 +0000 | [diff] [blame] | 620 | if ((r = sshkey_check_cert_sigtype(key, |
| 621 | options.ca_sign_algorithms)) != 0) { |
| 622 | logit("%s: certificate signature algorithm %s: %s", __func__, |
| 623 | (key->cert == NULL || key->cert->signature_type == NULL) ? |
| 624 | "(null)" : key->cert->signature_type, ssh_err(r)); |
| 625 | return 0; |
| 626 | } |
| 627 | |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 628 | return 1; |
| 629 | } |
| 630 | |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 631 | static int |
| 632 | sockaddr_is_local(struct sockaddr *hostaddr) |
| 633 | { |
| 634 | switch (hostaddr->sa_family) { |
| 635 | case AF_INET: |
| 636 | return (ntohl(((struct sockaddr_in *)hostaddr)-> |
| 637 | sin_addr.s_addr) >> 24) == IN_LOOPBACKNET; |
| 638 | case AF_INET6: |
| 639 | return IN6_IS_ADDR_LOOPBACK( |
| 640 | &(((struct sockaddr_in6 *)hostaddr)->sin6_addr)); |
| 641 | default: |
| 642 | return 0; |
| 643 | } |
| 644 | } |
| 645 | |
| 646 | /* |
| 647 | * Prepare the hostname and ip address strings that are used to lookup |
| 648 | * host keys in known_hosts files. These may have a port number appended. |
| 649 | */ |
| 650 | void |
| 651 | get_hostfile_hostname_ipaddr(char *hostname, struct sockaddr *hostaddr, |
| 652 | u_short port, char **hostfile_hostname, char **hostfile_ipaddr) |
| 653 | { |
| 654 | char ntop[NI_MAXHOST]; |
| 655 | socklen_t addrlen; |
| 656 | |
| 657 | switch (hostaddr == NULL ? -1 : hostaddr->sa_family) { |
| 658 | case -1: |
| 659 | addrlen = 0; |
| 660 | break; |
| 661 | case AF_INET: |
| 662 | addrlen = sizeof(struct sockaddr_in); |
| 663 | break; |
| 664 | case AF_INET6: |
| 665 | addrlen = sizeof(struct sockaddr_in6); |
| 666 | break; |
| 667 | default: |
| 668 | addrlen = sizeof(struct sockaddr); |
| 669 | break; |
| 670 | } |
| 671 | |
| 672 | /* |
| 673 | * We don't have the remote ip-address for connections |
| 674 | * using a proxy command |
| 675 | */ |
| 676 | if (hostfile_ipaddr != NULL) { |
| 677 | if (options.proxy_command == NULL) { |
| 678 | if (getnameinfo(hostaddr, addrlen, |
| 679 | ntop, sizeof(ntop), NULL, 0, NI_NUMERICHOST) != 0) |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 680 | fatal("%s: getnameinfo failed", __func__); |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 681 | *hostfile_ipaddr = put_host_port(ntop, port); |
| 682 | } else { |
| 683 | *hostfile_ipaddr = xstrdup("<no hostip for proxy " |
| 684 | "command>"); |
| 685 | } |
| 686 | } |
| 687 | |
| 688 | /* |
| 689 | * Allow the user to record the key under a different name or |
| 690 | * differentiate a non-standard port. This is useful for ssh |
| 691 | * tunneling over forwarded connections or if you run multiple |
| 692 | * sshd's on different ports on the same machine. |
| 693 | */ |
| 694 | if (hostfile_hostname != NULL) { |
| 695 | if (options.host_key_alias != NULL) { |
| 696 | *hostfile_hostname = xstrdup(options.host_key_alias); |
| 697 | debug("using hostkeyalias: %s", *hostfile_hostname); |
| 698 | } else { |
| 699 | *hostfile_hostname = put_host_port(hostname, port); |
| 700 | } |
| 701 | } |
| 702 | } |
| 703 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 704 | /* |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 705 | * check whether the supplied host key is valid, return -1 if the key |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 706 | * is not valid. user_hostfile[0] will not be updated if 'readonly' is true. |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 707 | */ |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 708 | #define RDRW 0 |
| 709 | #define RDONLY 1 |
| 710 | #define ROQUIET 2 |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 711 | static int |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 712 | check_host_key(char *hostname, struct sockaddr *hostaddr, u_short port, |
markus@openbsd.org | 54d90ac | 2017-05-30 08:52:19 +0000 | [diff] [blame] | 713 | struct sshkey *host_key, int readonly, |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 714 | char **user_hostfiles, u_int num_user_hostfiles, |
| 715 | char **system_hostfiles, u_int num_system_hostfiles) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 716 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 717 | HostStatus host_status; |
| 718 | HostStatus ip_status; |
markus@openbsd.org | 54d90ac | 2017-05-30 08:52:19 +0000 | [diff] [blame] | 719 | struct sshkey *raw_key = NULL; |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 720 | char *ip = NULL, *host = NULL; |
| 721 | char hostline[1000], *hostp, *fp, *ra; |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 722 | char msg[1024]; |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 723 | const char *type; |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 724 | const struct hostkey_entry *host_found, *ip_found; |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 725 | int len, cancelled_forwarding = 0, confirmed; |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 726 | int local = sockaddr_is_local(hostaddr); |
markus@openbsd.org | beb965b | 2017-05-30 14:13:40 +0000 | [diff] [blame] | 727 | int r, want_cert = sshkey_is_cert(host_key), host_ip_differ = 0; |
djm@openbsd.org | 8d4f872 | 2015-01-26 03:04:45 +0000 | [diff] [blame] | 728 | int hostkey_trusted = 0; /* Known or explicitly accepted by user */ |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 729 | struct hostkeys *host_hostkeys, *ip_hostkeys; |
| 730 | u_int i; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 731 | |
| 732 | /* |
| 733 | * Force accepting of the host key for loopback/localhost. The |
| 734 | * problem is that if the home directory is NFS-mounted to multiple |
| 735 | * machines, localhost will refer to a different machine in each of |
| 736 | * them, and the user will get bogus HOST_CHANGED warnings. This |
| 737 | * essentially disables host authentication for localhost; however, |
| 738 | * this is probably not a real problem. |
| 739 | */ |
Ben Lindstrom | 3cecc9a | 2001-10-03 17:39:38 +0000 | [diff] [blame] | 740 | if (options.no_host_authentication_for_localhost == 1 && local && |
| 741 | options.host_key_alias == NULL) { |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 742 | debug("Forcing accepting of host key for " |
| 743 | "loopback/localhost."); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 744 | return 0; |
Damien Miller | 34132e5 | 2000-01-14 15:45:46 +1100 | [diff] [blame] | 745 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 746 | |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 747 | /* |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 748 | * Prepare the hostname and address strings used for hostkey lookup. |
| 749 | * In some cases, these will have a port number appended. |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 750 | */ |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 751 | get_hostfile_hostname_ipaddr(hostname, hostaddr, port, &host, &ip); |
Darren Tucker | 78913e0 | 2008-06-13 04:47:34 +1000 | [diff] [blame] | 752 | |
| 753 | /* |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 754 | * Turn off check_host_ip if the connection is to localhost, via proxy |
| 755 | * command or if we don't have a hostname to compare with |
| 756 | */ |
Darren Tucker | da34553 | 2006-07-10 23:04:19 +1000 | [diff] [blame] | 757 | if (options.check_host_ip && (local || |
| 758 | strcmp(hostname, ip) == 0 || options.proxy_command != NULL)) |
Damien Miller | aae6c61 | 1999-12-06 11:47:28 +1100 | [diff] [blame] | 759 | options.check_host_ip = 0; |
| 760 | |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 761 | host_hostkeys = init_hostkeys(); |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 762 | for (i = 0; i < num_user_hostfiles; i++) |
| 763 | load_hostkeys(host_hostkeys, host, user_hostfiles[i]); |
| 764 | for (i = 0; i < num_system_hostfiles; i++) |
| 765 | load_hostkeys(host_hostkeys, host, system_hostfiles[i]); |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 766 | |
| 767 | ip_hostkeys = NULL; |
| 768 | if (!want_cert && options.check_host_ip) { |
| 769 | ip_hostkeys = init_hostkeys(); |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 770 | for (i = 0; i < num_user_hostfiles; i++) |
| 771 | load_hostkeys(ip_hostkeys, ip, user_hostfiles[i]); |
| 772 | for (i = 0; i < num_system_hostfiles; i++) |
| 773 | load_hostkeys(ip_hostkeys, ip, system_hostfiles[i]); |
Ben Lindstrom | 4dccfa5 | 2000-12-28 16:40:05 +0000 | [diff] [blame] | 774 | } |
| 775 | |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 776 | retry: |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 777 | /* Reload these as they may have changed on cert->key downgrade */ |
markus@openbsd.org | beb965b | 2017-05-30 14:13:40 +0000 | [diff] [blame] | 778 | want_cert = sshkey_is_cert(host_key); |
| 779 | type = sshkey_type(host_key); |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 780 | |
Ben Lindstrom | 4dccfa5 | 2000-12-28 16:40:05 +0000 | [diff] [blame] | 781 | /* |
Damien Miller | 788f212 | 2005-11-05 15:14:59 +1100 | [diff] [blame] | 782 | * 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] | 783 | * hosts or in the systemwide list. |
| 784 | */ |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 785 | host_status = check_key_in_hostkeys(host_hostkeys, host_key, |
| 786 | &host_found); |
| 787 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 788 | /* |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 789 | * Also perform check for the ip address, skip the check if we are |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 790 | * localhost, looking for a certificate, or the hostname was an ip |
| 791 | * address to begin with. |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 792 | */ |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 793 | if (!want_cert && ip_hostkeys != NULL) { |
| 794 | ip_status = check_key_in_hostkeys(ip_hostkeys, host_key, |
| 795 | &ip_found); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 796 | if (host_status == HOST_CHANGED && |
djm@openbsd.org | 2aefdf1 | 2019-09-13 04:31:19 +0000 | [diff] [blame] | 797 | (ip_status != HOST_CHANGED || |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 798 | (ip_found != NULL && |
markus@openbsd.org | beb965b | 2017-05-30 14:13:40 +0000 | [diff] [blame] | 799 | !sshkey_equal(ip_found->key, host_found->key)))) |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 800 | host_ip_differ = 1; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 801 | } else |
| 802 | ip_status = host_status; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 803 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 804 | switch (host_status) { |
| 805 | case HOST_OK: |
| 806 | /* The host is known and the key matches. */ |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 807 | debug("Host '%.200s' is known and matches the %s host %s.", |
| 808 | host, type, want_cert ? "certificate" : "key"); |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 809 | debug("Found %s in %s:%lu", want_cert ? "CA key" : "key", |
| 810 | host_found->file, host_found->line); |
djm@openbsd.org | 6f8ca3b | 2017-06-24 05:35:05 +0000 | [diff] [blame] | 811 | if (want_cert && |
| 812 | !check_host_cert(options.host_key_alias == NULL ? |
| 813 | hostname : options.host_key_alias, host_key)) |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 814 | goto fail; |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 815 | if (options.check_host_ip && ip_status == HOST_NEW) { |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 816 | if (readonly || want_cert) |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 817 | logit("%s host key for IP address " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 818 | "'%.128s' not in list of known hosts.", |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 819 | type, ip); |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 820 | else if (!add_host_to_hostfile(user_hostfiles[0], ip, |
Damien Miller | e177615 | 2005-03-01 21:47:37 +1100 | [diff] [blame] | 821 | host_key, options.hash_known_hosts)) |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 822 | logit("Failed to add the %s host key for IP " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 823 | "address '%.128s' to the list of known " |
dtucker@openbsd.org | 496aeb2 | 2015-05-28 05:41:29 +0000 | [diff] [blame] | 824 | "hosts (%.500s).", type, ip, |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 825 | user_hostfiles[0]); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 826 | else |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 827 | logit("Warning: Permanently added the %s host " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 828 | "key for IP address '%.128s' to the list " |
| 829 | "of known hosts.", type, ip); |
Damien Miller | 1028824 | 2008-06-30 00:04:03 +1000 | [diff] [blame] | 830 | } else if (options.visual_host_key) { |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 831 | fp = sshkey_fingerprint(host_key, |
djm@openbsd.org | 56d1c83 | 2014-12-21 22:27:55 +0000 | [diff] [blame] | 832 | options.fingerprint_hash, SSH_FP_DEFAULT); |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 833 | ra = sshkey_fingerprint(host_key, |
djm@openbsd.org | 56d1c83 | 2014-12-21 22:27:55 +0000 | [diff] [blame] | 834 | options.fingerprint_hash, SSH_FP_RANDOMART); |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 835 | if (fp == NULL || ra == NULL) |
| 836 | fatal("%s: sshkey_fingerprint fail", __func__); |
djm@openbsd.org | ac3451d | 2015-09-04 03:57:38 +0000 | [diff] [blame] | 837 | logit("Host key fingerprint is %s\n%s", fp, ra); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 838 | free(ra); |
| 839 | free(fp); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 840 | } |
djm@openbsd.org | 8d4f872 | 2015-01-26 03:04:45 +0000 | [diff] [blame] | 841 | hostkey_trusted = 1; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 842 | break; |
| 843 | case HOST_NEW: |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 844 | if (options.host_key_alias == NULL && port != 0 && |
| 845 | port != SSH_DEFAULT_PORT) { |
| 846 | debug("checking without port identifier"); |
Damien Miller | ece92c8 | 2008-11-03 19:25:03 +1100 | [diff] [blame] | 847 | if (check_host_key(hostname, hostaddr, 0, host_key, |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 848 | ROQUIET, user_hostfiles, num_user_hostfiles, |
| 849 | system_hostfiles, num_system_hostfiles) == 0) { |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 850 | debug("found matching key w/out port"); |
| 851 | break; |
| 852 | } |
| 853 | } |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 854 | if (readonly || want_cert) |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 855 | goto fail; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 856 | /* The host is new. */ |
djm@openbsd.org | 22376d2 | 2017-09-03 23:33:13 +0000 | [diff] [blame] | 857 | if (options.strict_host_key_checking == |
| 858 | SSH_STRICT_HOSTKEY_YES) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 859 | /* |
| 860 | * User has requested strict host key checking. We |
| 861 | * will not add the host key automatically. The only |
| 862 | * alternative left is to abort. |
| 863 | */ |
| 864 | error("No %s host key is known for %.200s and you " |
| 865 | "have requested strict checking.", type, host); |
| 866 | goto fail; |
djm@openbsd.org | 22376d2 | 2017-09-03 23:33:13 +0000 | [diff] [blame] | 867 | } else if (options.strict_host_key_checking == |
| 868 | SSH_STRICT_HOSTKEY_ASK) { |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 869 | char msg1[1024], msg2[1024]; |
| 870 | |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 871 | if (show_other_keys(host_hostkeys, host_key)) |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 872 | snprintf(msg1, sizeof(msg1), |
Damien Miller | 0dc1bef | 2005-07-17 17:22:45 +1000 | [diff] [blame] | 873 | "\nbut keys of different type are already" |
| 874 | " known for this host."); |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 875 | else |
| 876 | snprintf(msg1, sizeof(msg1), "."); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 877 | /* The default */ |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 878 | fp = sshkey_fingerprint(host_key, |
djm@openbsd.org | 56d1c83 | 2014-12-21 22:27:55 +0000 | [diff] [blame] | 879 | options.fingerprint_hash, SSH_FP_DEFAULT); |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 880 | ra = sshkey_fingerprint(host_key, |
djm@openbsd.org | 56d1c83 | 2014-12-21 22:27:55 +0000 | [diff] [blame] | 881 | options.fingerprint_hash, SSH_FP_RANDOMART); |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 882 | if (fp == NULL || ra == NULL) |
| 883 | fatal("%s: sshkey_fingerprint fail", __func__); |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 884 | msg2[0] = '\0'; |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 885 | if (options.verify_host_key_dns) { |
Damien Miller | 150b557 | 2003-11-17 21:19:29 +1100 | [diff] [blame] | 886 | if (matching_host_key_dns) |
Damien Miller | 7392ae6 | 2003-06-11 22:05:25 +1000 | [diff] [blame] | 887 | snprintf(msg2, sizeof(msg2), |
| 888 | "Matching host key fingerprint" |
| 889 | " found in DNS.\n"); |
| 890 | else |
| 891 | snprintf(msg2, sizeof(msg2), |
| 892 | "No matching host key fingerprint" |
| 893 | " found in DNS.\n"); |
| 894 | } |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 895 | snprintf(msg, sizeof(msg), |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 896 | "The authenticity of host '%.200s (%s)' can't be " |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 897 | "established%s\n" |
Damien Miller | 1028824 | 2008-06-30 00:04:03 +1000 | [diff] [blame] | 898 | "%s key fingerprint is %s.%s%s\n%s" |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 899 | "Are you sure you want to continue connecting " |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 900 | "(yes/no/[fingerprint])? ", |
Damien Miller | 1028824 | 2008-06-30 00:04:03 +1000 | [diff] [blame] | 901 | host, ip, msg1, type, fp, |
| 902 | options.visual_host_key ? "\n" : "", |
| 903 | options.visual_host_key ? ra : "", |
| 904 | msg2); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 905 | free(ra); |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 906 | confirmed = confirm(msg, fp); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 907 | free(fp); |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 908 | if (!confirmed) |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 909 | goto fail; |
djm@openbsd.org | 8d4f872 | 2015-01-26 03:04:45 +0000 | [diff] [blame] | 910 | hostkey_trusted = 1; /* user explicitly confirmed */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 911 | } |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 912 | /* |
djm@openbsd.org | 22376d2 | 2017-09-03 23:33:13 +0000 | [diff] [blame] | 913 | * If in "new" or "off" strict mode, add the key automatically |
| 914 | * to the local known_hosts file. |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 915 | */ |
Damien Miller | 1227d4c | 2005-03-02 12:06:51 +1100 | [diff] [blame] | 916 | if (options.check_host_ip && ip_status == HOST_NEW) { |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 917 | snprintf(hostline, sizeof(hostline), "%s,%s", host, ip); |
Damien Miller | 1227d4c | 2005-03-02 12:06:51 +1100 | [diff] [blame] | 918 | hostp = hostline; |
| 919 | if (options.hash_known_hosts) { |
| 920 | /* Add hash of host and IP separately */ |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 921 | r = add_host_to_hostfile(user_hostfiles[0], |
| 922 | host, host_key, options.hash_known_hosts) && |
| 923 | add_host_to_hostfile(user_hostfiles[0], ip, |
Damien Miller | 1227d4c | 2005-03-02 12:06:51 +1100 | [diff] [blame] | 924 | host_key, options.hash_known_hosts); |
| 925 | } else { |
| 926 | /* Add unhashed "host,ip" */ |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 927 | r = add_host_to_hostfile(user_hostfiles[0], |
Damien Miller | 1227d4c | 2005-03-02 12:06:51 +1100 | [diff] [blame] | 928 | hostline, host_key, |
| 929 | options.hash_known_hosts); |
| 930 | } |
| 931 | } else { |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 932 | r = add_host_to_hostfile(user_hostfiles[0], host, |
| 933 | host_key, options.hash_known_hosts); |
Damien Miller | 1227d4c | 2005-03-02 12:06:51 +1100 | [diff] [blame] | 934 | hostp = host; |
| 935 | } |
| 936 | |
| 937 | if (!r) |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 938 | logit("Failed to add the host to the list of known " |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 939 | "hosts (%.500s).", user_hostfiles[0]); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 940 | else |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 941 | logit("Warning: Permanently added '%.200s' (%s) to the " |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 942 | "list of known hosts.", hostp, type); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 943 | break; |
Damien Miller | 1aed65e | 2010-03-04 21:53:35 +1100 | [diff] [blame] | 944 | case HOST_REVOKED: |
| 945 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
| 946 | error("@ WARNING: REVOKED HOST KEY DETECTED! @"); |
| 947 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
| 948 | error("The %s host key for %s is marked as revoked.", type, host); |
| 949 | error("This could mean that a stolen key is being used to"); |
| 950 | error("impersonate this host."); |
| 951 | |
| 952 | /* |
| 953 | * If strict host key checking is in use, the user will have |
| 954 | * to edit the key manually and we can only abort. |
| 955 | */ |
djm@openbsd.org | 22376d2 | 2017-09-03 23:33:13 +0000 | [diff] [blame] | 956 | if (options.strict_host_key_checking != |
| 957 | SSH_STRICT_HOSTKEY_OFF) { |
Damien Miller | 1aed65e | 2010-03-04 21:53:35 +1100 | [diff] [blame] | 958 | error("%s host key for %.200s was revoked and you have " |
| 959 | "requested strict checking.", type, host); |
| 960 | goto fail; |
| 961 | } |
| 962 | goto continue_unsafe; |
| 963 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 964 | case HOST_CHANGED: |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 965 | if (want_cert) { |
| 966 | /* |
| 967 | * This is only a debug() since it is valid to have |
| 968 | * CAs with wildcard DNS matches that don't match |
| 969 | * all hosts that one might visit. |
| 970 | */ |
| 971 | debug("Host certificate authority does not " |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 972 | "match %s in %s:%lu", CA_MARKER, |
| 973 | host_found->file, host_found->line); |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 974 | goto fail; |
| 975 | } |
Damien Miller | da82839 | 2006-08-05 11:35:45 +1000 | [diff] [blame] | 976 | if (readonly == ROQUIET) |
| 977 | goto fail; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 978 | if (options.check_host_ip && host_ip_differ) { |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 979 | char *key_msg; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 980 | if (ip_status == HOST_NEW) |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 981 | key_msg = "is unknown"; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 982 | else if (ip_status == HOST_OK) |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 983 | key_msg = "is unchanged"; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 984 | else |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 985 | key_msg = "has a different value"; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 986 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
| 987 | error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @"); |
| 988 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
Damien Miller | e247cc4 | 2000-05-07 12:03:14 +1000 | [diff] [blame] | 989 | error("The %s host key for %s has changed,", type, host); |
Darren Tucker | ff4454d | 2008-06-13 10:21:51 +1000 | [diff] [blame] | 990 | error("and the key for the corresponding IP address %s", ip); |
Darren Tucker | 3f9fdc7 | 2004-06-22 12:56:01 +1000 | [diff] [blame] | 991 | error("%s. This could either mean that", key_msg); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 992 | error("DNS SPOOFING is happening or the IP address for the host"); |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 993 | error("and its host key have changed at the same time."); |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 994 | if (ip_status != HOST_NEW) |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 995 | error("Offending key for IP in %s:%lu", |
| 996 | ip_found->file, ip_found->line); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 997 | } |
| 998 | /* The host key has changed. */ |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 999 | warn_changed_key(host_key); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1000 | error("Add correct host key in %.100s to get rid of this message.", |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 1001 | user_hostfiles[0]); |
markus@openbsd.org | beb965b | 2017-05-30 14:13:40 +0000 | [diff] [blame] | 1002 | error("Offending %s key in %s:%lu", |
| 1003 | sshkey_type(host_found->key), |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1004 | host_found->file, host_found->line); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 1005 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 1006 | /* |
| 1007 | * If strict host key checking is in use, the user will have |
| 1008 | * to edit the key manually and we can only abort. |
| 1009 | */ |
djm@openbsd.org | 22376d2 | 2017-09-03 23:33:13 +0000 | [diff] [blame] | 1010 | if (options.strict_host_key_checking != |
| 1011 | SSH_STRICT_HOSTKEY_OFF) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1012 | error("%s host key for %.200s has changed and you have " |
| 1013 | "requested strict checking.", type, host); |
| 1014 | goto fail; |
| 1015 | } |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 1016 | |
Damien Miller | 1aed65e | 2010-03-04 21:53:35 +1100 | [diff] [blame] | 1017 | continue_unsafe: |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 1018 | /* |
| 1019 | * If strict host key checking has not been requested, allow |
Damien Miller | 941ac45 | 2003-06-04 20:31:53 +1000 | [diff] [blame] | 1020 | * the connection but without MITM-able authentication or |
Damien Miller | 437edb9 | 2006-08-05 09:11:13 +1000 | [diff] [blame] | 1021 | * forwarding. |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 1022 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1023 | if (options.password_authentication) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1024 | error("Password authentication is disabled to avoid " |
| 1025 | "man-in-the-middle attacks."); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1026 | options.password_authentication = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 1027 | cancelled_forwarding = 1; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1028 | } |
Damien Miller | 941ac45 | 2003-06-04 20:31:53 +1000 | [diff] [blame] | 1029 | if (options.kbd_interactive_authentication) { |
| 1030 | error("Keyboard-interactive authentication is disabled" |
| 1031 | " to avoid man-in-the-middle attacks."); |
| 1032 | options.kbd_interactive_authentication = 0; |
| 1033 | options.challenge_response_authentication = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 1034 | cancelled_forwarding = 1; |
Damien Miller | 941ac45 | 2003-06-04 20:31:53 +1000 | [diff] [blame] | 1035 | } |
| 1036 | if (options.challenge_response_authentication) { |
| 1037 | error("Challenge/response authentication is disabled" |
| 1038 | " to avoid man-in-the-middle attacks."); |
| 1039 | options.challenge_response_authentication = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 1040 | cancelled_forwarding = 1; |
Damien Miller | 941ac45 | 2003-06-04 20:31:53 +1000 | [diff] [blame] | 1041 | } |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1042 | if (options.forward_agent) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1043 | error("Agent forwarding is disabled to avoid " |
| 1044 | "man-in-the-middle attacks."); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1045 | options.forward_agent = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 1046 | cancelled_forwarding = 1; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1047 | } |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 1048 | if (options.forward_x11) { |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1049 | error("X11 forwarding is disabled to avoid " |
| 1050 | "man-in-the-middle attacks."); |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 1051 | options.forward_x11 = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 1052 | cancelled_forwarding = 1; |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 1053 | } |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1054 | if (options.num_local_forwards > 0 || |
| 1055 | options.num_remote_forwards > 0) { |
| 1056 | error("Port forwarding is disabled to avoid " |
| 1057 | "man-in-the-middle attacks."); |
| 1058 | options.num_local_forwards = |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 1059 | options.num_remote_forwards = 0; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 1060 | cancelled_forwarding = 1; |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 1061 | } |
Damien Miller | 437edb9 | 2006-08-05 09:11:13 +1000 | [diff] [blame] | 1062 | if (options.tun_open != SSH_TUNMODE_NO) { |
| 1063 | error("Tunnel forwarding is disabled to avoid " |
| 1064 | "man-in-the-middle attacks."); |
| 1065 | options.tun_open = SSH_TUNMODE_NO; |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 1066 | cancelled_forwarding = 1; |
Damien Miller | 437edb9 | 2006-08-05 09:11:13 +1000 | [diff] [blame] | 1067 | } |
Darren Tucker | 068e01f | 2008-07-02 22:33:55 +1000 | [diff] [blame] | 1068 | if (options.exit_on_forward_failure && cancelled_forwarding) |
| 1069 | fatal("Error: forwarding disabled due to host key " |
| 1070 | "check failure"); |
| 1071 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 1072 | /* |
| 1073 | * XXX Should permit the user to change to use the new id. |
| 1074 | * This could be done by converting the host key to an |
| 1075 | * identifying sentence, tell that the host identifies itself |
Darren Tucker | e2b3674 | 2010-01-13 22:42:34 +1100 | [diff] [blame] | 1076 | * by that sentence, and ask the user if he/she wishes to |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 1077 | * accept the authentication. |
| 1078 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1079 | break; |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1080 | case HOST_FOUND: |
| 1081 | fatal("internal error"); |
| 1082 | break; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 1083 | } |
Ben Lindstrom | c72745a | 2000-12-02 19:03:54 +0000 | [diff] [blame] | 1084 | |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 1085 | if (options.check_host_ip && host_status != HOST_CHANGED && |
| 1086 | ip_status == HOST_CHANGED) { |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 1087 | snprintf(msg, sizeof(msg), |
| 1088 | "Warning: the %s host key for '%.200s' " |
| 1089 | "differs from the key for the IP address '%.128s'" |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1090 | "\nOffending key for IP in %s:%lu", |
| 1091 | type, host, ip, ip_found->file, ip_found->line); |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 1092 | if (host_status == HOST_OK) { |
| 1093 | len = strlen(msg); |
| 1094 | snprintf(msg + len, sizeof(msg) - len, |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1095 | "\nMatching host key in %s:%lu", |
| 1096 | host_found->file, host_found->line); |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 1097 | } |
djm@openbsd.org | 22376d2 | 2017-09-03 23:33:13 +0000 | [diff] [blame] | 1098 | if (options.strict_host_key_checking == |
| 1099 | SSH_STRICT_HOSTKEY_ASK) { |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 1100 | strlcat(msg, "\nAre you sure you want " |
| 1101 | "to continue connecting (yes/no)? ", sizeof(msg)); |
dtucker@openbsd.org | 05b9a46 | 2019-01-24 17:00:29 +0000 | [diff] [blame] | 1102 | if (!confirm(msg, NULL)) |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1103 | goto fail; |
djm@openbsd.org | 22376d2 | 2017-09-03 23:33:13 +0000 | [diff] [blame] | 1104 | } else if (options.strict_host_key_checking != |
| 1105 | SSH_STRICT_HOSTKEY_OFF) { |
| 1106 | logit("%s", msg); |
| 1107 | error("Exiting, you have requested strict checking."); |
| 1108 | goto fail; |
Damien Miller | 49d795c | 2002-01-22 23:34:12 +1100 | [diff] [blame] | 1109 | } else { |
Damien Miller | ab2db41 | 2003-06-02 19:09:13 +1000 | [diff] [blame] | 1110 | logit("%s", msg); |
Ben Lindstrom | 5c1fbab | 2001-01-03 03:51:15 +0000 | [diff] [blame] | 1111 | } |
| 1112 | } |
| 1113 | |
djm@openbsd.org | 8d4f872 | 2015-01-26 03:04:45 +0000 | [diff] [blame] | 1114 | if (!hostkey_trusted && options.update_hostkeys) { |
| 1115 | debug("%s: hostkey not known or explicitly trusted: " |
| 1116 | "disabling UpdateHostkeys", __func__); |
| 1117 | options.update_hostkeys = 0; |
| 1118 | } |
| 1119 | |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 1120 | free(ip); |
| 1121 | free(host); |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1122 | if (host_hostkeys != NULL) |
| 1123 | free_hostkeys(host_hostkeys); |
| 1124 | if (ip_hostkeys != NULL) |
| 1125 | free_hostkeys(ip_hostkeys); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1126 | return 0; |
| 1127 | |
| 1128 | fail: |
Damien Miller | 1aed65e | 2010-03-04 21:53:35 +1100 | [diff] [blame] | 1129 | if (want_cert && host_status != HOST_REVOKED) { |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 1130 | /* |
| 1131 | * No matching certificate. Downgrade cert to raw key and |
| 1132 | * search normally. |
| 1133 | */ |
| 1134 | debug("No matching CA found. Retry with plain key"); |
markus@openbsd.org | beb965b | 2017-05-30 14:13:40 +0000 | [diff] [blame] | 1135 | if ((r = sshkey_from_private(host_key, &raw_key)) != 0) |
| 1136 | fatal("%s: sshkey_from_private: %s", |
| 1137 | __func__, ssh_err(r)); |
| 1138 | if ((r = sshkey_drop_cert(raw_key)) != 0) |
| 1139 | fatal("Couldn't drop certificate: %s", ssh_err(r)); |
Damien Miller | 0a80ca1 | 2010-02-27 07:55:05 +1100 | [diff] [blame] | 1140 | host_key = raw_key; |
| 1141 | goto retry; |
| 1142 | } |
dtucker@openbsd.org | f1f047f | 2018-02-07 22:52:45 +0000 | [diff] [blame] | 1143 | sshkey_free(raw_key); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 1144 | free(ip); |
| 1145 | free(host); |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1146 | if (host_hostkeys != NULL) |
| 1147 | free_hostkeys(host_hostkeys); |
| 1148 | if (ip_hostkeys != NULL) |
| 1149 | free_hostkeys(ip_hostkeys); |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1150 | return -1; |
| 1151 | } |
| 1152 | |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 1153 | /* returns 0 if key verifies or -1 if key does NOT verify */ |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1154 | int |
markus@openbsd.org | 54d90ac | 2017-05-30 08:52:19 +0000 | [diff] [blame] | 1155 | verify_host_key(char *host, struct sockaddr *hostaddr, struct sshkey *host_key) |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1156 | { |
djm@openbsd.org | f96516d | 2015-11-19 01:09:38 +0000 | [diff] [blame] | 1157 | u_int i; |
Damien Miller | 6b37fbb | 2014-07-04 08:59:24 +1000 | [diff] [blame] | 1158 | int r = -1, flags = 0; |
djm@openbsd.org | f96516d | 2015-11-19 01:09:38 +0000 | [diff] [blame] | 1159 | char valid[64], *fp = NULL, *cafp = NULL; |
djm@openbsd.org | 5e39a49 | 2014-12-04 02:24:32 +0000 | [diff] [blame] | 1160 | struct sshkey *plain = NULL; |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1161 | |
djm@openbsd.org | 5e39a49 | 2014-12-04 02:24:32 +0000 | [diff] [blame] | 1162 | if ((fp = sshkey_fingerprint(host_key, |
djm@openbsd.org | 56d1c83 | 2014-12-21 22:27:55 +0000 | [diff] [blame] | 1163 | options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) { |
djm@openbsd.org | 5e39a49 | 2014-12-04 02:24:32 +0000 | [diff] [blame] | 1164 | error("%s: fingerprint host key: %s", __func__, ssh_err(r)); |
| 1165 | r = -1; |
| 1166 | goto out; |
| 1167 | } |
Ben Lindstrom | d6481ea | 2001-06-25 04:37:41 +0000 | [diff] [blame] | 1168 | |
djm@openbsd.org | f96516d | 2015-11-19 01:09:38 +0000 | [diff] [blame] | 1169 | if (sshkey_is_cert(host_key)) { |
| 1170 | if ((cafp = sshkey_fingerprint(host_key->cert->signature_key, |
| 1171 | options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) { |
| 1172 | error("%s: fingerprint CA key: %s", |
| 1173 | __func__, ssh_err(r)); |
| 1174 | r = -1; |
| 1175 | goto out; |
| 1176 | } |
| 1177 | sshkey_format_cert_validity(host_key->cert, |
| 1178 | valid, sizeof(valid)); |
| 1179 | debug("Server host certificate: %s %s, serial %llu " |
| 1180 | "ID \"%s\" CA %s %s valid %s", |
| 1181 | sshkey_ssh_name(host_key), fp, |
djm@openbsd.org | 8ca915f | 2015-11-20 01:45:29 +0000 | [diff] [blame] | 1182 | (unsigned long long)host_key->cert->serial, |
| 1183 | host_key->cert->key_id, |
djm@openbsd.org | f96516d | 2015-11-19 01:09:38 +0000 | [diff] [blame] | 1184 | sshkey_ssh_name(host_key->cert->signature_key), cafp, |
| 1185 | valid); |
| 1186 | for (i = 0; i < host_key->cert->nprincipals; i++) { |
| 1187 | debug2("Server host certificate hostname: %s", |
| 1188 | host_key->cert->principals[i]); |
| 1189 | } |
| 1190 | } else { |
djm@openbsd.org | 97f4d30 | 2017-04-30 23:13:25 +0000 | [diff] [blame] | 1191 | debug("Server host key: %s %s", sshkey_ssh_name(host_key), fp); |
djm@openbsd.org | f96516d | 2015-11-19 01:09:38 +0000 | [diff] [blame] | 1192 | } |
djm@openbsd.org | 5e39a49 | 2014-12-04 02:24:32 +0000 | [diff] [blame] | 1193 | |
| 1194 | if (sshkey_equal(previous_host_key, host_key)) { |
| 1195 | debug2("%s: server host key %s %s matches cached key", |
| 1196 | __func__, sshkey_type(host_key), fp); |
| 1197 | r = 0; |
| 1198 | goto out; |
| 1199 | } |
| 1200 | |
| 1201 | /* Check in RevokedHostKeys file if specified */ |
| 1202 | if (options.revoked_host_keys != NULL) { |
| 1203 | r = sshkey_check_revoked(host_key, options.revoked_host_keys); |
| 1204 | switch (r) { |
| 1205 | case 0: |
| 1206 | break; /* not revoked */ |
| 1207 | case SSH_ERR_KEY_REVOKED: |
| 1208 | error("Host key %s %s revoked by file %s", |
| 1209 | sshkey_type(host_key), fp, |
| 1210 | options.revoked_host_keys); |
| 1211 | r = -1; |
| 1212 | goto out; |
| 1213 | default: |
| 1214 | error("Error checking host key %s %s in " |
| 1215 | "revoked keys file %s: %s", sshkey_type(host_key), |
| 1216 | fp, options.revoked_host_keys, ssh_err(r)); |
| 1217 | r = -1; |
| 1218 | goto out; |
| 1219 | } |
Damien Miller | 6b37fbb | 2014-07-04 08:59:24 +1000 | [diff] [blame] | 1220 | } |
| 1221 | |
Damien Miller | 7d6a9fb | 2014-04-20 13:23:43 +1000 | [diff] [blame] | 1222 | if (options.verify_host_key_dns) { |
| 1223 | /* |
| 1224 | * XXX certs are not yet supported for DNS, so downgrade |
| 1225 | * them and try the plain key. |
| 1226 | */ |
djm@openbsd.org | 5e39a49 | 2014-12-04 02:24:32 +0000 | [diff] [blame] | 1227 | if ((r = sshkey_from_private(host_key, &plain)) != 0) |
| 1228 | goto out; |
| 1229 | if (sshkey_is_cert(plain)) |
| 1230 | sshkey_drop_cert(plain); |
Damien Miller | 7d6a9fb | 2014-04-20 13:23:43 +1000 | [diff] [blame] | 1231 | if (verify_host_key_dns(host, hostaddr, plain, &flags) == 0) { |
| 1232 | if (flags & DNS_VERIFY_FOUND) { |
| 1233 | if (options.verify_host_key_dns == 1 && |
| 1234 | flags & DNS_VERIFY_MATCH && |
| 1235 | flags & DNS_VERIFY_SECURE) { |
Damien Miller | 6b37fbb | 2014-07-04 08:59:24 +1000 | [diff] [blame] | 1236 | r = 0; |
djm@openbsd.org | 5e39a49 | 2014-12-04 02:24:32 +0000 | [diff] [blame] | 1237 | goto out; |
Damien Miller | 7d6a9fb | 2014-04-20 13:23:43 +1000 | [diff] [blame] | 1238 | } |
| 1239 | if (flags & DNS_VERIFY_MATCH) { |
| 1240 | matching_host_key_dns = 1; |
| 1241 | } else { |
djm@openbsd.org | aea59a0 | 2017-09-14 04:32:21 +0000 | [diff] [blame] | 1242 | warn_changed_key(plain); |
| 1243 | error("Update the SSHFP RR in DNS " |
| 1244 | "with the new host key to get rid " |
| 1245 | "of this message."); |
Damien Miller | 7d6a9fb | 2014-04-20 13:23:43 +1000 | [diff] [blame] | 1246 | } |
Damien Miller | 150b557 | 2003-11-17 21:19:29 +1100 | [diff] [blame] | 1247 | } |
Damien Miller | 37876e9 | 2003-05-15 10:19:46 +1000 | [diff] [blame] | 1248 | } |
| 1249 | } |
Damien Miller | 6b37fbb | 2014-07-04 08:59:24 +1000 | [diff] [blame] | 1250 | r = check_host_key(host, hostaddr, options.port, host_key, RDRW, |
Damien Miller | 295ee63 | 2011-05-29 21:42:31 +1000 | [diff] [blame] | 1251 | options.user_hostfiles, options.num_user_hostfiles, |
| 1252 | options.system_hostfiles, options.num_system_hostfiles); |
Damien Miller | 6b37fbb | 2014-07-04 08:59:24 +1000 | [diff] [blame] | 1253 | |
djm@openbsd.org | 5e39a49 | 2014-12-04 02:24:32 +0000 | [diff] [blame] | 1254 | out: |
| 1255 | sshkey_free(plain); |
| 1256 | free(fp); |
djm@openbsd.org | f96516d | 2015-11-19 01:09:38 +0000 | [diff] [blame] | 1257 | free(cafp); |
Damien Miller | 6b37fbb | 2014-07-04 08:59:24 +1000 | [diff] [blame] | 1258 | if (r == 0 && host_key != NULL) { |
markus@openbsd.org | beb965b | 2017-05-30 14:13:40 +0000 | [diff] [blame] | 1259 | sshkey_free(previous_host_key); |
| 1260 | r = sshkey_from_private(host_key, &previous_host_key); |
Damien Miller | 6b37fbb | 2014-07-04 08:59:24 +1000 | [diff] [blame] | 1261 | } |
| 1262 | |
| 1263 | return r; |
Damien Miller | a34a28b | 1999-12-14 10:47:15 +1100 | [diff] [blame] | 1264 | } |
Damien Miller | 037a0dc | 1999-12-07 15:38:31 +1100 | [diff] [blame] | 1265 | |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1266 | /* |
| 1267 | * Starts a dialog with the server, and authenticates the current user on the |
| 1268 | * server. This does not need any extra privileges. The basic connection |
| 1269 | * to the server must already have been established before this is called. |
| 1270 | * If login fails, this function prints an error and never returns. |
| 1271 | * This function does not require super-user privileges. |
| 1272 | */ |
| 1273 | void |
djm@openbsd.org | 0a843d9 | 2018-12-27 03:25:24 +0000 | [diff] [blame] | 1274 | ssh_login(struct ssh *ssh, Sensitive *sensitive, const char *orighost, |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1275 | struct sockaddr *hostaddr, u_short port, struct passwd *pw, int timeout_ms) |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1276 | { |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 1277 | char *host; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 1278 | char *server_user, *local_user; |
djm@openbsd.org | 5becbec | 2020-03-13 04:01:56 +0000 | [diff] [blame] | 1279 | int r; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 1280 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 1281 | local_user = xstrdup(pw->pw_name); |
| 1282 | server_user = options.user ? options.user : local_user; |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1283 | |
| 1284 | /* Convert the user-supplied hostname into all lowercase. */ |
| 1285 | host = xstrdup(orighost); |
Damien Miller | 0faf747 | 2013-10-17 11:47:23 +1100 | [diff] [blame] | 1286 | lowercase(host); |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1287 | |
| 1288 | /* Exchange protocol version identification strings with the server. */ |
djm@openbsd.org | 5becbec | 2020-03-13 04:01:56 +0000 | [diff] [blame] | 1289 | if ((r = kex_exchange_identification(ssh, timeout_ms, NULL)) != 0) |
| 1290 | sshpkt_fatal(ssh, r, "banner exchange"); |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1291 | |
| 1292 | /* Put the connection into non-blocking mode. */ |
djm@openbsd.org | 0a843d9 | 2018-12-27 03:25:24 +0000 | [diff] [blame] | 1293 | ssh_packet_set_nonblocking(ssh); |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1294 | |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1295 | /* key exchange */ |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1296 | /* authenticate user */ |
dtucker@openbsd.org | bb2289e | 2015-04-14 04:17:03 +0000 | [diff] [blame] | 1297 | debug("Authenticating to %s:%d as '%s'", host, port, server_user); |
djm@openbsd.org | 0a843d9 | 2018-12-27 03:25:24 +0000 | [diff] [blame] | 1298 | ssh_kex2(ssh, host, hostaddr, port); |
| 1299 | ssh_userauth2(ssh, local_user, server_user, host, sensitive); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 1300 | free(local_user); |
dtucker@openbsd.org | 1c554a5 | 2019-05-03 03:27:38 +0000 | [diff] [blame] | 1301 | free(host); |
Damien Miller | 396691a | 2000-01-20 22:44:08 +1100 | [diff] [blame] | 1302 | } |
Damien Miller | 79438cc | 2001-02-16 12:34:57 +1100 | [diff] [blame] | 1303 | |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1304 | /* print all known host keys for a given host, but skip keys of given type */ |
| 1305 | static int |
markus@openbsd.org | 54d90ac | 2017-05-30 08:52:19 +0000 | [diff] [blame] | 1306 | show_other_keys(struct hostkeys *hostkeys, struct sshkey *key) |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1307 | { |
Damien Miller | 106bf1c | 2013-12-29 17:54:03 +1100 | [diff] [blame] | 1308 | int type[] = { |
Damien Miller | 106bf1c | 2013-12-29 17:54:03 +1100 | [diff] [blame] | 1309 | KEY_RSA, |
| 1310 | KEY_DSA, |
| 1311 | KEY_ECDSA, |
| 1312 | KEY_ED25519, |
markus@openbsd.org | 1b11ea7 | 2018-02-23 15:58:37 +0000 | [diff] [blame] | 1313 | KEY_XMSS, |
Damien Miller | 106bf1c | 2013-12-29 17:54:03 +1100 | [diff] [blame] | 1314 | -1 |
| 1315 | }; |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1316 | int i, ret = 0; |
| 1317 | char *fp, *ra; |
| 1318 | const struct hostkey_entry *found; |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1319 | |
| 1320 | for (i = 0; type[i] != -1; i++) { |
| 1321 | if (type[i] == key->type) |
| 1322 | continue; |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1323 | if (!lookup_key_in_hostkeys_by_type(hostkeys, type[i], &found)) |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1324 | continue; |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 1325 | fp = sshkey_fingerprint(found->key, |
djm@openbsd.org | 56d1c83 | 2014-12-21 22:27:55 +0000 | [diff] [blame] | 1326 | options.fingerprint_hash, SSH_FP_DEFAULT); |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 1327 | ra = sshkey_fingerprint(found->key, |
djm@openbsd.org | 56d1c83 | 2014-12-21 22:27:55 +0000 | [diff] [blame] | 1328 | options.fingerprint_hash, SSH_FP_RANDOMART); |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 1329 | if (fp == NULL || ra == NULL) |
| 1330 | fatal("%s: sshkey_fingerprint fail", __func__); |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1331 | logit("WARNING: %s key found for host %s\n" |
| 1332 | "in %s:%lu\n" |
| 1333 | "%s key fingerprint %s.", |
markus@openbsd.org | 5467fbc | 2018-07-11 18:53:29 +0000 | [diff] [blame] | 1334 | sshkey_type(found->key), |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1335 | found->host, found->file, found->line, |
markus@openbsd.org | 5467fbc | 2018-07-11 18:53:29 +0000 | [diff] [blame] | 1336 | sshkey_type(found->key), fp); |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1337 | if (options.visual_host_key) |
| 1338 | logit("%s", ra); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 1339 | free(ra); |
| 1340 | free(fp); |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1341 | ret = 1; |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1342 | } |
Damien Miller | d925dcd | 2010-12-01 12:21:51 +1100 | [diff] [blame] | 1343 | return ret; |
Ben Lindstrom | 3ed6640 | 2002-08-01 01:21:56 +0000 | [diff] [blame] | 1344 | } |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1345 | |
| 1346 | static void |
markus@openbsd.org | 54d90ac | 2017-05-30 08:52:19 +0000 | [diff] [blame] | 1347 | warn_changed_key(struct sshkey *host_key) |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1348 | { |
| 1349 | char *fp; |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1350 | |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 1351 | fp = sshkey_fingerprint(host_key, options.fingerprint_hash, |
djm@openbsd.org | 56d1c83 | 2014-12-21 22:27:55 +0000 | [diff] [blame] | 1352 | SSH_FP_DEFAULT); |
djm@openbsd.org | 9ce86c9 | 2015-01-28 22:36:00 +0000 | [diff] [blame] | 1353 | if (fp == NULL) |
| 1354 | fatal("%s: sshkey_fingerprint fail", __func__); |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1355 | |
| 1356 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
| 1357 | error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @"); |
| 1358 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
| 1359 | error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!"); |
| 1360 | error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!"); |
Damien Miller | 05c8997 | 2011-01-06 22:42:04 +1100 | [diff] [blame] | 1361 | error("It is also possible that a host key has just been changed."); |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1362 | error("The fingerprint for the %s key sent by the remote host is\n%s.", |
markus@openbsd.org | 5467fbc | 2018-07-11 18:53:29 +0000 | [diff] [blame] | 1363 | sshkey_type(host_key), fp); |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1364 | error("Please contact your system administrator."); |
| 1365 | |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 1366 | free(fp); |
Damien Miller | 5a38897 | 2003-11-17 21:10:47 +1100 | [diff] [blame] | 1367 | } |
Damien Miller | d27b947 | 2005-12-13 19:29:02 +1100 | [diff] [blame] | 1368 | |
| 1369 | /* |
| 1370 | * Execute a local command |
| 1371 | */ |
| 1372 | int |
| 1373 | ssh_local_cmd(const char *args) |
| 1374 | { |
| 1375 | char *shell; |
| 1376 | pid_t pid; |
| 1377 | int status; |
Damien Miller | ed3a8eb | 2011-01-07 10:02:52 +1100 | [diff] [blame] | 1378 | void (*osighand)(int); |
Damien Miller | d27b947 | 2005-12-13 19:29:02 +1100 | [diff] [blame] | 1379 | |
| 1380 | if (!options.permit_local_command || |
| 1381 | args == NULL || !*args) |
| 1382 | return (1); |
| 1383 | |
Damien Miller | 38d9a96 | 2010-10-07 22:07:11 +1100 | [diff] [blame] | 1384 | if ((shell = getenv("SHELL")) == NULL || *shell == '\0') |
Damien Miller | d27b947 | 2005-12-13 19:29:02 +1100 | [diff] [blame] | 1385 | shell = _PATH_BSHELL; |
| 1386 | |
dtucker@openbsd.org | 3bf2a6a | 2020-01-23 07:10:22 +0000 | [diff] [blame] | 1387 | osighand = ssh_signal(SIGCHLD, SIG_DFL); |
Damien Miller | d27b947 | 2005-12-13 19:29:02 +1100 | [diff] [blame] | 1388 | pid = fork(); |
| 1389 | if (pid == 0) { |
dtucker@openbsd.org | 3bf2a6a | 2020-01-23 07:10:22 +0000 | [diff] [blame] | 1390 | ssh_signal(SIGPIPE, SIG_DFL); |
Damien Miller | d27b947 | 2005-12-13 19:29:02 +1100 | [diff] [blame] | 1391 | debug3("Executing %s -c \"%s\"", shell, args); |
| 1392 | execl(shell, shell, "-c", args, (char *)NULL); |
| 1393 | error("Couldn't execute %s -c \"%s\": %s", |
| 1394 | shell, args, strerror(errno)); |
| 1395 | _exit(1); |
| 1396 | } else if (pid == -1) |
| 1397 | fatal("fork failed: %.100s", strerror(errno)); |
| 1398 | while (waitpid(pid, &status, 0) == -1) |
| 1399 | if (errno != EINTR) |
| 1400 | fatal("Couldn't wait for child: %s", strerror(errno)); |
dtucker@openbsd.org | 3bf2a6a | 2020-01-23 07:10:22 +0000 | [diff] [blame] | 1401 | ssh_signal(SIGCHLD, osighand); |
Damien Miller | d27b947 | 2005-12-13 19:29:02 +1100 | [diff] [blame] | 1402 | |
| 1403 | if (!WIFEXITED(status)) |
| 1404 | return (1); |
| 1405 | |
| 1406 | return (WEXITSTATUS(status)); |
| 1407 | } |
jcs@openbsd.org | f361df4 | 2015-11-15 22:26:49 +0000 | [diff] [blame] | 1408 | |
| 1409 | void |
djm@openbsd.org | 022ce92 | 2020-01-25 07:17:18 +0000 | [diff] [blame] | 1410 | maybe_add_key_to_agent(const char *authfile, struct sshkey *private, |
| 1411 | const char *comment, const char *passphrase) |
jcs@openbsd.org | f361df4 | 2015-11-15 22:26:49 +0000 | [diff] [blame] | 1412 | { |
| 1413 | int auth_sock = -1, r; |
djm@openbsd.org | eebec62 | 2019-10-31 21:20:38 +0000 | [diff] [blame] | 1414 | const char *skprovider = NULL; |
jcs@openbsd.org | f361df4 | 2015-11-15 22:26:49 +0000 | [diff] [blame] | 1415 | |
| 1416 | if (options.add_keys_to_agent == 0) |
| 1417 | return; |
| 1418 | |
| 1419 | if ((r = ssh_get_authentication_socket(&auth_sock)) != 0) { |
| 1420 | debug3("no authentication agent, not adding key"); |
| 1421 | return; |
| 1422 | } |
| 1423 | |
| 1424 | if (options.add_keys_to_agent == 2 && |
| 1425 | !ask_permission("Add key %s (%s) to agent?", authfile, comment)) { |
| 1426 | debug3("user denied adding this key"); |
dtucker@openbsd.org | 566b3a4 | 2017-03-10 03:22:40 +0000 | [diff] [blame] | 1427 | close(auth_sock); |
jcs@openbsd.org | f361df4 | 2015-11-15 22:26:49 +0000 | [diff] [blame] | 1428 | return; |
| 1429 | } |
markus@openbsd.org | 2c55744 | 2019-11-12 19:33:08 +0000 | [diff] [blame] | 1430 | if (sshkey_is_sk(private)) |
djm@openbsd.org | eebec62 | 2019-10-31 21:20:38 +0000 | [diff] [blame] | 1431 | skprovider = options.sk_provider; |
djm@openbsd.org | 022ce92 | 2020-01-25 07:17:18 +0000 | [diff] [blame] | 1432 | if ((r = ssh_add_identity_constrained(auth_sock, private, |
| 1433 | comment == NULL ? authfile : comment, 0, |
djm@openbsd.org | eebec62 | 2019-10-31 21:20:38 +0000 | [diff] [blame] | 1434 | (options.add_keys_to_agent == 3), 0, skprovider)) == 0) |
jcs@openbsd.org | f361df4 | 2015-11-15 22:26:49 +0000 | [diff] [blame] | 1435 | debug("identity added to agent: %s", authfile); |
| 1436 | else |
| 1437 | debug("could not add identity to agent: %s (%d)", authfile, r); |
dtucker@openbsd.org | 566b3a4 | 2017-03-10 03:22:40 +0000 | [diff] [blame] | 1438 | close(auth_sock); |
jcs@openbsd.org | f361df4 | 2015-11-15 22:26:49 +0000 | [diff] [blame] | 1439 | } |