Damien Miller | 8668706 | 2014-07-02 15:28:02 +1000 | [diff] [blame] | 1 | /* $OpenBSD: auth-chall.c,v 1.14 2014/06/24 01:13:21 djm Exp $ */ |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 2 | /* |
Ben Lindstrom | 92a2e38 | 2001-03-05 06:59:27 +0000 | [diff] [blame] | 3 | * Copyright (c) 2001 Markus Friedl. All rights reserved. |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * |
| 14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 15 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 16 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 17 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 18 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 19 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 20 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 21 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 23 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 24 | */ |
| 25 | |
| 26 | #include "includes.h" |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 27 | |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 28 | #include <sys/types.h> |
Damien Miller | 8668706 | 2014-07-02 15:28:02 +1000 | [diff] [blame] | 29 | #include <stdarg.h> |
| 30 | #include <stdlib.h> |
| 31 | #include <stdio.h> |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 32 | |
| 33 | #include "xmalloc.h" |
| 34 | #include "key.h" |
| 35 | #include "hostfile.h" |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 36 | #include "auth.h" |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 37 | #include "log.h" |
Damien Miller | 7acefbb | 2014-07-18 14:11:24 +1000 | [diff] [blame] | 38 | #include "misc.h" |
Darren Tucker | 3c66080 | 2005-01-20 22:20:50 +1100 | [diff] [blame] | 39 | #include "servconf.h" |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 40 | |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 41 | /* limited protocol v1 interface to kbd-interactive authentication */ |
| 42 | |
| 43 | extern KbdintDevice *devices[]; |
| 44 | static KbdintDevice *device; |
Darren Tucker | 3c66080 | 2005-01-20 22:20:50 +1100 | [diff] [blame] | 45 | extern ServerOptions options; |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 46 | |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 47 | char * |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 48 | get_challenge(Authctxt *authctxt) |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 49 | { |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 50 | char *challenge, *name, *info, **prompts; |
| 51 | u_int i, numprompts; |
| 52 | u_int *echo_on; |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 53 | |
Darren Tucker | 3c66080 | 2005-01-20 22:20:50 +1100 | [diff] [blame] | 54 | #ifdef USE_PAM |
| 55 | if (!options.use_pam) |
| 56 | remove_kbdint_device("pam"); |
| 57 | #endif |
| 58 | |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 59 | device = devices[0]; /* we always use the 1st device for protocol 1 */ |
| 60 | if (device == NULL) |
| 61 | return NULL; |
| 62 | if ((authctxt->kbdintctxt = device->init_ctx(authctxt)) == NULL) |
| 63 | return NULL; |
| 64 | if (device->query(authctxt->kbdintctxt, &name, &info, |
| 65 | &numprompts, &prompts, &echo_on)) { |
| 66 | device->free_ctx(authctxt->kbdintctxt); |
| 67 | authctxt->kbdintctxt = NULL; |
| 68 | return NULL; |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 69 | } |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 70 | if (numprompts < 1) |
| 71 | fatal("get_challenge: numprompts < 1"); |
| 72 | challenge = xstrdup(prompts[0]); |
| 73 | for (i = 0; i < numprompts; i++) |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 74 | free(prompts[i]); |
| 75 | free(prompts); |
| 76 | free(name); |
| 77 | free(echo_on); |
| 78 | free(info); |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 79 | |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 80 | return (challenge); |
Damien Miller | 60396b0 | 2001-02-18 17:01:00 +1100 | [diff] [blame] | 81 | } |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 82 | int |
| 83 | verify_response(Authctxt *authctxt, const char *response) |
| 84 | { |
Damien Miller | 3e8f41e | 2003-11-17 21:09:50 +1100 | [diff] [blame] | 85 | char *resp[1], *name, *info, **prompts; |
| 86 | u_int i, numprompts, *echo_on; |
| 87 | int authenticated = 0; |
Ben Lindstrom | cf0809d | 2001-01-19 15:44:10 +0000 | [diff] [blame] | 88 | |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 89 | if (device == NULL) |
| 90 | return 0; |
| 91 | if (authctxt->kbdintctxt == NULL) |
| 92 | return 0; |
| 93 | resp[0] = (char *)response; |
Damien Miller | 3e8f41e | 2003-11-17 21:09:50 +1100 | [diff] [blame] | 94 | switch (device->respond(authctxt->kbdintctxt, 1, resp)) { |
| 95 | case 0: /* Success */ |
| 96 | authenticated = 1; |
| 97 | break; |
| 98 | case 1: /* Postponed - retry with empty query for PAM */ |
| 99 | if ((device->query(authctxt->kbdintctxt, &name, &info, |
| 100 | &numprompts, &prompts, &echo_on)) != 0) |
| 101 | break; |
Damien Miller | a8e06ce | 2003-11-21 23:48:55 +1100 | [diff] [blame] | 102 | if (numprompts == 0 && |
Damien Miller | 3e8f41e | 2003-11-17 21:09:50 +1100 | [diff] [blame] | 103 | device->respond(authctxt->kbdintctxt, 0, resp) == 0) |
| 104 | authenticated = 1; |
Damien Miller | 4f9f42a | 2003-05-10 19:28:02 +1000 | [diff] [blame] | 105 | |
Damien Miller | 3e8f41e | 2003-11-17 21:09:50 +1100 | [diff] [blame] | 106 | for (i = 0; i < numprompts; i++) |
Darren Tucker | f60845f | 2013-06-02 08:07:31 +1000 | [diff] [blame] | 107 | free(prompts[i]); |
| 108 | free(prompts); |
| 109 | free(name); |
| 110 | free(echo_on); |
| 111 | free(info); |
Damien Miller | 3e8f41e | 2003-11-17 21:09:50 +1100 | [diff] [blame] | 112 | break; |
Damien Miller | 4f9f42a | 2003-05-10 19:28:02 +1000 | [diff] [blame] | 113 | } |
Ben Lindstrom | 551ea37 | 2001-06-05 18:56:16 +0000 | [diff] [blame] | 114 | device->free_ctx(authctxt->kbdintctxt); |
| 115 | authctxt->kbdintctxt = NULL; |
Damien Miller | 3e8f41e | 2003-11-17 21:09:50 +1100 | [diff] [blame] | 116 | return authenticated; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 117 | } |
Damien Miller | 4f9f42a | 2003-05-10 19:28:02 +1000 | [diff] [blame] | 118 | void |
| 119 | abandon_challenge_response(Authctxt *authctxt) |
| 120 | { |
| 121 | if (authctxt->kbdintctxt != NULL) { |
| 122 | device->free_ctx(authctxt->kbdintctxt); |
| 123 | authctxt->kbdintctxt = NULL; |
| 124 | } |
| 125 | } |