Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 1 | /* |
| 2 | * Kerberos v5 authentication and ticket-passing routines. |
Ben Lindstrom | 6328ab3 | 2002-03-22 02:54:23 +0000 | [diff] [blame] | 3 | * |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 4 | * $FreeBSD: src/crypto/openssh/auth-krb5.c,v 1.6 2001/02/13 16:58:04 assar Exp $ |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 5 | */ |
Ben Lindstrom | eacc71b | 2002-03-22 01:22:27 +0000 | [diff] [blame] | 6 | /* |
| 7 | * Copyright (c) 2002 Daniel Kouril. All rights reserved. |
| 8 | * |
| 9 | * Redistribution and use in source and binary forms, with or without |
| 10 | * modification, are permitted provided that the following conditions |
| 11 | * are met: |
| 12 | * 1. Redistributions of source code must retain the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer. |
| 14 | * 2. Redistributions in binary form must reproduce the above copyright |
| 15 | * notice, this list of conditions and the following disclaimer in the |
| 16 | * documentation and/or other materials provided with the distribution. |
| 17 | * |
| 18 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 19 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 20 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 21 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 22 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 23 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 24 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 25 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 26 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 27 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 28 | */ |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 29 | |
| 30 | #include "includes.h" |
Damien Miller | 3e3b514 | 2003-11-17 21:13:40 +1100 | [diff] [blame^] | 31 | RCSID("$OpenBSD: auth-krb5.c,v 1.14 2003/11/04 08:54:09 djm Exp $"); |
Ben Lindstrom | 05764b9 | 2002-03-05 01:53:02 +0000 | [diff] [blame] | 32 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 33 | #include "ssh.h" |
| 34 | #include "ssh1.h" |
| 35 | #include "packet.h" |
| 36 | #include "xmalloc.h" |
| 37 | #include "log.h" |
| 38 | #include "servconf.h" |
| 39 | #include "uidswap.h" |
| 40 | #include "auth.h" |
| 41 | |
| 42 | #ifdef KRB5 |
Damien Miller | 9c61769 | 2003-05-14 14:31:11 +1000 | [diff] [blame] | 43 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 44 | #include <krb5.h> |
| 45 | |
| 46 | extern ServerOptions options; |
| 47 | |
| 48 | static int |
| 49 | krb5_init(void *context) |
| 50 | { |
| 51 | Authctxt *authctxt = (Authctxt *)context; |
| 52 | krb5_error_code problem; |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 53 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 54 | if (authctxt->krb5_ctx == NULL) { |
| 55 | problem = krb5_init_context(&authctxt->krb5_ctx); |
| 56 | if (problem) |
| 57 | return (problem); |
| 58 | krb5_init_ets(authctxt->krb5_ctx); |
| 59 | } |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 60 | return (0); |
| 61 | } |
| 62 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 63 | int |
| 64 | auth_krb5_password(Authctxt *authctxt, const char *password) |
| 65 | { |
Damien Miller | fd4c9ee | 2002-04-13 11:04:40 +1000 | [diff] [blame] | 66 | #ifndef HEIMDAL |
| 67 | krb5_creds creds; |
| 68 | krb5_principal server; |
| 69 | char ccname[40]; |
| 70 | int tmpfd; |
| 71 | #endif |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 72 | krb5_error_code problem; |
Darren Tucker | ec0943a | 2003-08-11 22:55:36 +1000 | [diff] [blame] | 73 | krb5_ccache ccache = NULL; |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 74 | |
Damien Miller | 3e3b514 | 2003-11-17 21:13:40 +1100 | [diff] [blame^] | 75 | if (!authctxt->valid) |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 76 | return (0); |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 77 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 78 | temporarily_use_uid(authctxt->pw); |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 79 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 80 | problem = krb5_init(authctxt); |
| 81 | if (problem) |
| 82 | goto out; |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 83 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 84 | problem = krb5_parse_name(authctxt->krb5_ctx, authctxt->pw->pw_name, |
| 85 | &authctxt->krb5_user); |
| 86 | if (problem) |
| 87 | goto out; |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 88 | |
Damien Miller | fd4c9ee | 2002-04-13 11:04:40 +1000 | [diff] [blame] | 89 | #ifdef HEIMDAL |
Darren Tucker | ec0943a | 2003-08-11 22:55:36 +1000 | [diff] [blame] | 90 | problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_mcc_ops, &ccache); |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 91 | if (problem) |
| 92 | goto out; |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 93 | |
Darren Tucker | ec0943a | 2003-08-11 22:55:36 +1000 | [diff] [blame] | 94 | problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache, |
| 95 | authctxt->krb5_user); |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 96 | if (problem) |
| 97 | goto out; |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 98 | |
| 99 | restore_uid(); |
Darren Tucker | ec0943a | 2003-08-11 22:55:36 +1000 | [diff] [blame] | 100 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 101 | problem = krb5_verify_user(authctxt->krb5_ctx, authctxt->krb5_user, |
Darren Tucker | ec0943a | 2003-08-11 22:55:36 +1000 | [diff] [blame] | 102 | ccache, password, 1, NULL); |
| 103 | |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 104 | temporarily_use_uid(authctxt->pw); |
| 105 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 106 | if (problem) |
| 107 | goto out; |
Darren Tucker | ec0943a | 2003-08-11 22:55:36 +1000 | [diff] [blame] | 108 | problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_fcc_ops, |
| 109 | &authctxt->krb5_fwd_ccache); |
| 110 | if (problem) |
| 111 | goto out; |
| 112 | |
| 113 | problem = krb5_cc_copy_cache(authctxt->krb5_ctx, ccache, |
| 114 | authctxt->krb5_fwd_ccache); |
| 115 | krb5_cc_destroy(authctxt->krb5_ctx, ccache); |
| 116 | ccache = NULL; |
| 117 | if (problem) |
| 118 | goto out; |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 119 | |
Damien Miller | fd4c9ee | 2002-04-13 11:04:40 +1000 | [diff] [blame] | 120 | #else |
| 121 | problem = krb5_get_init_creds_password(authctxt->krb5_ctx, &creds, |
| 122 | authctxt->krb5_user, (char *)password, NULL, NULL, 0, NULL, NULL); |
| 123 | if (problem) |
| 124 | goto out; |
| 125 | |
| 126 | problem = krb5_sname_to_principal(authctxt->krb5_ctx, NULL, NULL, |
| 127 | KRB5_NT_SRV_HST, &server); |
| 128 | if (problem) |
| 129 | goto out; |
| 130 | |
| 131 | restore_uid(); |
| 132 | problem = krb5_verify_init_creds(authctxt->krb5_ctx, &creds, server, |
| 133 | NULL, NULL, NULL); |
| 134 | krb5_free_principal(authctxt->krb5_ctx, server); |
| 135 | temporarily_use_uid(authctxt->pw); |
| 136 | if (problem) |
| 137 | goto out; |
| 138 | |
| 139 | if (!krb5_kuserok(authctxt->krb5_ctx, authctxt->krb5_user, |
| 140 | authctxt->pw->pw_name)) { |
Ben Lindstrom | 5a6abda | 2002-06-09 19:41:48 +0000 | [diff] [blame] | 141 | problem = -1; |
Damien Miller | fd4c9ee | 2002-04-13 11:04:40 +1000 | [diff] [blame] | 142 | goto out; |
| 143 | } |
| 144 | |
| 145 | snprintf(ccname,sizeof(ccname),"FILE:/tmp/krb5cc_%d_XXXXXX",geteuid()); |
| 146 | |
| 147 | if ((tmpfd = mkstemp(ccname+strlen("FILE:")))==-1) { |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 148 | logit("mkstemp(): %.100s", strerror(errno)); |
Damien Miller | fd4c9ee | 2002-04-13 11:04:40 +1000 | [diff] [blame] | 149 | problem = errno; |
| 150 | goto out; |
| 151 | } |
| 152 | |
| 153 | if (fchmod(tmpfd,S_IRUSR | S_IWUSR) == -1) { |
Damien Miller | 996acd2 | 2003-04-09 20:59:48 +1000 | [diff] [blame] | 154 | logit("fchmod(): %.100s", strerror(errno)); |
Damien Miller | fd4c9ee | 2002-04-13 11:04:40 +1000 | [diff] [blame] | 155 | close(tmpfd); |
| 156 | problem = errno; |
| 157 | goto out; |
| 158 | } |
| 159 | close(tmpfd); |
| 160 | |
| 161 | problem = krb5_cc_resolve(authctxt->krb5_ctx, ccname, &authctxt->krb5_fwd_ccache); |
| 162 | if (problem) |
| 163 | goto out; |
| 164 | |
| 165 | problem = krb5_cc_initialize(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache, |
| 166 | authctxt->krb5_user); |
| 167 | if (problem) |
| 168 | goto out; |
| 169 | |
| 170 | problem= krb5_cc_store_cred(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache, |
| 171 | &creds); |
| 172 | if (problem) |
| 173 | goto out; |
| 174 | #endif |
| 175 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 176 | authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache); |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 177 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 178 | out: |
| 179 | restore_uid(); |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 180 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 181 | if (problem) { |
Darren Tucker | ec0943a | 2003-08-11 22:55:36 +1000 | [diff] [blame] | 182 | if (ccache) |
| 183 | krb5_cc_destroy(authctxt->krb5_ctx, ccache); |
| 184 | |
Damien Miller | fd4c9ee | 2002-04-13 11:04:40 +1000 | [diff] [blame] | 185 | if (authctxt->krb5_ctx != NULL && problem!=-1) |
Ben Lindstrom | b855028 | 2002-02-26 17:46:11 +0000 | [diff] [blame] | 186 | debug("Kerberos password authentication failed: %s", |
| 187 | krb5_get_err_text(authctxt->krb5_ctx, problem)); |
| 188 | else |
| 189 | debug("Kerberos password authentication failed: %d", |
| 190 | problem); |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 191 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 192 | krb5_cleanup_proc(authctxt); |
Damien Miller | db95e4e | 2002-02-13 16:56:44 +1100 | [diff] [blame] | 193 | |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 194 | if (options.kerberos_or_local_passwd) |
| 195 | return (-1); |
| 196 | else |
| 197 | return (0); |
| 198 | } |
| 199 | return (1); |
| 200 | } |
| 201 | |
| 202 | void |
Darren Tucker | 3e33cec | 2003-10-02 16:12:36 +1000 | [diff] [blame] | 203 | krb5_cleanup_proc(Authctxt *authctxt) |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 204 | { |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 205 | debug("krb5_cleanup_proc called"); |
| 206 | if (authctxt->krb5_fwd_ccache) { |
| 207 | krb5_cc_destroy(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache); |
| 208 | authctxt->krb5_fwd_ccache = NULL; |
| 209 | } |
| 210 | if (authctxt->krb5_user) { |
| 211 | krb5_free_principal(authctxt->krb5_ctx, authctxt->krb5_user); |
| 212 | authctxt->krb5_user = NULL; |
| 213 | } |
Damien Miller | 964fed5 | 2001-09-25 12:58:23 +1000 | [diff] [blame] | 214 | if (authctxt->krb5_ctx) { |
| 215 | krb5_free_context(authctxt->krb5_ctx); |
| 216 | authctxt->krb5_ctx = NULL; |
| 217 | } |
| 218 | } |
| 219 | |
| 220 | #endif /* KRB5 */ |