Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 1 | /* |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| 4 | * All rights reserved |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 5 | * Rhosts or /etc/hosts.equiv authentication combined with RSA host |
| 6 | * authentication. |
| 7 | * |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 8 | * As far as I am concerned, the code I have written for this software |
| 9 | * can be used freely for any purpose. Any derived versions of this |
| 10 | * software must be clearly marked as such, and if the derived work is |
| 11 | * incompatible with the protocol description in the RFC file, it must be |
| 12 | * called by a name other than "ssh" or "Secure Shell". |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 13 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 14 | |
| 15 | #include "includes.h" |
Ben Lindstrom | a4789ef | 2001-06-25 04:40:49 +0000 | [diff] [blame] | 16 | RCSID("$OpenBSD: auth-rh-rsa.c,v 1.25 2001/06/23 03:04:42 markus Exp $"); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 17 | |
| 18 | #include "packet.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 19 | #include "xmalloc.h" |
| 20 | #include "uidswap.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 21 | #include "log.h" |
Damien Miller | 3226509 | 1999-11-12 11:33:04 +1100 | [diff] [blame] | 22 | #include "servconf.h" |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 23 | #include "key.h" |
| 24 | #include "hostfile.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 25 | #include "pathnames.h" |
| 26 | #include "auth.h" |
| 27 | #include "tildexpand.h" |
| 28 | #include "canohost.h" |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 29 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 30 | /* |
| 31 | * Tries to authenticate the user using the .rhosts file and the host using |
| 32 | * its host key. Returns true if authentication succeeds. |
| 33 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 34 | |
Damien Miller | 4af5130 | 2000-04-16 11:18:38 +1000 | [diff] [blame] | 35 | int |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 36 | auth_rhosts_rsa(struct passwd *pw, const char *client_user, RSA *client_host_key) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 37 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 38 | extern ServerOptions options; |
| 39 | const char *canonical_hostname; |
| 40 | HostStatus host_status; |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 41 | Key *client_key; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 42 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 43 | debug("Trying rhosts with RSA host authentication for client user %.100s", client_user); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 44 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 45 | if (pw == NULL || client_host_key == NULL) |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 46 | return 0; |
| 47 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 48 | /* Check if we would accept it using rhosts authentication. */ |
| 49 | if (!auth_rhosts(pw, client_user)) |
| 50 | return 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 51 | |
Damien Miller | 3380426 | 2001-02-04 23:20:18 +1100 | [diff] [blame] | 52 | canonical_hostname = get_canonical_hostname( |
| 53 | options.reverse_mapping_check); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 54 | |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 55 | debug("Rhosts RSA authentication: canonical host %.900s", canonical_hostname); |
| 56 | |
| 57 | /* wrap the RSA key into a 'generic' key */ |
Damien Miller | 0bc1bd8 | 2000-11-13 22:57:25 +1100 | [diff] [blame] | 58 | client_key = key_new(KEY_RSA1); |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 59 | BN_copy(client_key->rsa->e, client_host_key->e); |
| 60 | BN_copy(client_key->rsa->n, client_host_key->n); |
Damien Miller | 3226509 | 1999-11-12 11:33:04 +1100 | [diff] [blame] | 61 | |
Ben Lindstrom | 83647ce | 2001-06-25 04:30:16 +0000 | [diff] [blame] | 62 | host_status = check_key_in_hostfiles(pw, client_key, canonical_hostname, |
| 63 | _PATH_SSH_SYSTEM_HOSTFILE, |
Ben Lindstrom | a4789ef | 2001-06-25 04:40:49 +0000 | [diff] [blame] | 64 | options.ignore_user_known_hosts ? NULL : _PATH_SSH_USER_HOSTFILE); |
Damien Miller | 33e511e | 1999-11-11 11:43:13 +1100 | [diff] [blame] | 65 | |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 66 | key_free(client_key); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 67 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 68 | if (host_status != HOST_OK) { |
| 69 | debug("Rhosts with RSA host authentication denied: unknown or invalid host key"); |
| 70 | packet_send_debug("Your host key cannot be verified: unknown or invalid host key."); |
| 71 | return 0; |
| 72 | } |
| 73 | /* A matching host key was found and is known. */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 74 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 75 | /* Perform the challenge-response dialog with the client for the host key. */ |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 76 | if (!auth_rsa_challenge_dialog(client_host_key)) { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 77 | log("Client on %.800s failed to respond correctly to host authentication.", |
| 78 | canonical_hostname); |
| 79 | return 0; |
| 80 | } |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 81 | /* |
| 82 | * We have authenticated the user using .rhosts or /etc/hosts.equiv, |
| 83 | * and the host using RSA. We accept the authentication. |
| 84 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 85 | |
| 86 | verbose("Rhosts with RSA host authentication accepted for %.100s, %.100s on %.700s.", |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 87 | pw->pw_name, client_user, canonical_hostname); |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 88 | packet_send_debug("Rhosts with RSA host authentication accepted."); |
| 89 | return 1; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 90 | } |