blob: 85949247836df32607f558f0aaa16345ebd9e66b [file] [log] [blame]
Damien Miller964fed52001-09-25 12:58:23 +10001/*
2 * Kerberos v5 authentication and ticket-passing routines.
Ben Lindstrom6328ab32002-03-22 02:54:23 +00003 *
Damien Miller964fed52001-09-25 12:58:23 +10004 * $FreeBSD: src/crypto/openssh/auth-krb5.c,v 1.6 2001/02/13 16:58:04 assar Exp $
Damien Miller964fed52001-09-25 12:58:23 +10005 */
Ben Lindstromeacc71b2002-03-22 01:22:27 +00006/*
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 Miller964fed52001-09-25 12:58:23 +100029
30#include "includes.h"
Damien Millera8e06ce2003-11-21 23:48:55 +110031RCSID("$OpenBSD: auth-krb5.c,v 1.15 2003/11/21 11:57:02 djm Exp $");
Ben Lindstrom05764b92002-03-05 01:53:02 +000032
Damien Miller964fed52001-09-25 12:58:23 +100033#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
43#include <krb5.h>
44
45extern ServerOptions options;
46
47static int
48krb5_init(void *context)
49{
50 Authctxt *authctxt = (Authctxt *)context;
51 krb5_error_code problem;
Damien Millerdb95e4e2002-02-13 16:56:44 +110052
Damien Miller964fed52001-09-25 12:58:23 +100053 if (authctxt->krb5_ctx == NULL) {
54 problem = krb5_init_context(&authctxt->krb5_ctx);
55 if (problem)
56 return (problem);
57 krb5_init_ets(authctxt->krb5_ctx);
58 }
Damien Miller964fed52001-09-25 12:58:23 +100059 return (0);
60}
61
Damien Miller964fed52001-09-25 12:58:23 +100062int
63auth_krb5_password(Authctxt *authctxt, const char *password)
64{
Damien Millerfd4c9ee2002-04-13 11:04:40 +100065#ifndef HEIMDAL
66 krb5_creds creds;
67 krb5_principal server;
68 char ccname[40];
69 int tmpfd;
Damien Miller787b2ec2003-11-21 23:56:47 +110070#endif
Damien Miller964fed52001-09-25 12:58:23 +100071 krb5_error_code problem;
Darren Tuckerec0943a2003-08-11 22:55:36 +100072 krb5_ccache ccache = NULL;
Damien Millerdb95e4e2002-02-13 16:56:44 +110073
Damien Miller3e3b5142003-11-17 21:13:40 +110074 if (!authctxt->valid)
Damien Miller964fed52001-09-25 12:58:23 +100075 return (0);
Damien Millerdb95e4e2002-02-13 16:56:44 +110076
Damien Miller964fed52001-09-25 12:58:23 +100077 temporarily_use_uid(authctxt->pw);
Damien Millerdb95e4e2002-02-13 16:56:44 +110078
Damien Miller964fed52001-09-25 12:58:23 +100079 problem = krb5_init(authctxt);
80 if (problem)
81 goto out;
Damien Millerdb95e4e2002-02-13 16:56:44 +110082
Damien Miller964fed52001-09-25 12:58:23 +100083 problem = krb5_parse_name(authctxt->krb5_ctx, authctxt->pw->pw_name,
84 &authctxt->krb5_user);
85 if (problem)
86 goto out;
Damien Millerdb95e4e2002-02-13 16:56:44 +110087
Damien Millerfd4c9ee2002-04-13 11:04:40 +100088#ifdef HEIMDAL
Darren Tuckerec0943a2003-08-11 22:55:36 +100089 problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_mcc_ops, &ccache);
Damien Miller964fed52001-09-25 12:58:23 +100090 if (problem)
91 goto out;
Damien Millerdb95e4e2002-02-13 16:56:44 +110092
Darren Tuckerec0943a2003-08-11 22:55:36 +100093 problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache,
94 authctxt->krb5_user);
Damien Miller964fed52001-09-25 12:58:23 +100095 if (problem)
96 goto out;
Damien Millerdb95e4e2002-02-13 16:56:44 +110097
98 restore_uid();
Damien Miller787b2ec2003-11-21 23:56:47 +110099
Damien Miller964fed52001-09-25 12:58:23 +1000100 problem = krb5_verify_user(authctxt->krb5_ctx, authctxt->krb5_user,
Darren Tuckerec0943a2003-08-11 22:55:36 +1000101 ccache, password, 1, NULL);
Damien Miller787b2ec2003-11-21 23:56:47 +1100102
Damien Millerdb95e4e2002-02-13 16:56:44 +1100103 temporarily_use_uid(authctxt->pw);
104
Damien Miller964fed52001-09-25 12:58:23 +1000105 if (problem)
106 goto out;
Darren Tuckerec217ad2003-11-22 12:11:06 +1100107
Darren Tuckerec0943a2003-08-11 22:55:36 +1000108 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 Millerdb95e4e2002-02-13 16:56:44 +1100119
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000120#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;
Damien Miller787b2ec2003-11-21 23:56:47 +1100138
Damien Millera8e06ce2003-11-21 23:48:55 +1100139 if (!krb5_kuserok(authctxt->krb5_ctx, authctxt->krb5_user,
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000140 authctxt->pw->pw_name)) {
Ben Lindstrom5a6abda2002-06-09 19:41:48 +0000141 problem = -1;
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000142 goto out;
Damien Millera8e06ce2003-11-21 23:48:55 +1100143 }
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000144
145 snprintf(ccname,sizeof(ccname),"FILE:/tmp/krb5cc_%d_XXXXXX",geteuid());
Damien Miller787b2ec2003-11-21 23:56:47 +1100146
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000147 if ((tmpfd = mkstemp(ccname+strlen("FILE:")))==-1) {
Damien Miller996acd22003-04-09 20:59:48 +1000148 logit("mkstemp(): %.100s", strerror(errno));
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000149 problem = errno;
150 goto out;
151 }
Damien Miller787b2ec2003-11-21 23:56:47 +1100152
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000153 if (fchmod(tmpfd,S_IRUSR | S_IWUSR) == -1) {
Damien Miller996acd22003-04-09 20:59:48 +1000154 logit("fchmod(): %.100s", strerror(errno));
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000155 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;
Damien Miller787b2ec2003-11-21 23:56:47 +1100169
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000170 problem= krb5_cc_store_cred(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache,
171 &creds);
172 if (problem)
173 goto out;
Damien Miller787b2ec2003-11-21 23:56:47 +1100174#endif
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000175
Damien Miller964fed52001-09-25 12:58:23 +1000176 authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
Damien Millerdb95e4e2002-02-13 16:56:44 +1100177
Damien Miller964fed52001-09-25 12:58:23 +1000178 out:
179 restore_uid();
Damien Millerdb95e4e2002-02-13 16:56:44 +1100180
Damien Miller964fed52001-09-25 12:58:23 +1000181 if (problem) {
Darren Tuckerec0943a2003-08-11 22:55:36 +1000182 if (ccache)
183 krb5_cc_destroy(authctxt->krb5_ctx, ccache);
184
Damien Millerfd4c9ee2002-04-13 11:04:40 +1000185 if (authctxt->krb5_ctx != NULL && problem!=-1)
Ben Lindstromb8550282002-02-26 17:46:11 +0000186 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 Millerdb95e4e2002-02-13 16:56:44 +1100191
Damien Miller964fed52001-09-25 12:58:23 +1000192 krb5_cleanup_proc(authctxt);
Damien Millerdb95e4e2002-02-13 16:56:44 +1100193
Damien Miller964fed52001-09-25 12:58:23 +1000194 if (options.kerberos_or_local_passwd)
195 return (-1);
196 else
197 return (0);
198 }
199 return (1);
200}
201
202void
Darren Tucker3e33cec2003-10-02 16:12:36 +1000203krb5_cleanup_proc(Authctxt *authctxt)
Damien Miller964fed52001-09-25 12:58:23 +1000204{
Damien Miller964fed52001-09-25 12:58:23 +1000205 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 Miller964fed52001-09-25 12:58:23 +1000214 if (authctxt->krb5_ctx) {
215 krb5_free_context(authctxt->krb5_ctx);
216 authctxt->krb5_ctx = NULL;
217 }
218}
219
220#endif /* KRB5 */