1 /* $OpenBSD: gss-serv-krb5.c,v 1.7 2006/08/03 03:34:42 deraadt Exp $ */
4 * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 #include <sys/types.h>
47 extern ServerOptions options;
51 #elif !defined(MECHGLUE)
52 # ifdef HAVE_GSSAPI_KRB5_H
53 # include <gssapi_krb5.h>
54 # elif HAVE_GSSAPI_GSSAPI_KRB5_H
55 # include <gssapi/gssapi_krb5.h>
59 static krb5_context krb_context = NULL;
60 static int ssh_gssapi_krb5_init();
61 static int ssh_gssapi_krb5_userok(ssh_gssapi_client *client, char *name);
62 static int ssh_gssapi_krb5_localname(ssh_gssapi_client *client, char **user);
63 static void ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client);
65 ssh_gssapi_mech gssapi_kerberos_mech = {
66 "toWM5Slw5Ew8Mqkay+al2g==",
68 {9, "\x2A\x86\x48\x86\xF7\x12\x01\x02\x02"},
70 &ssh_gssapi_krb5_userok,
71 &ssh_gssapi_krb5_localname,
72 &ssh_gssapi_krb5_storecreds
75 /* Initialise the krb5 library, for the stuff that GSSAPI won't do */
78 ssh_gssapi_krb5_init(void)
80 krb5_error_code problem;
82 if (krb_context != NULL)
85 problem = krb5_init_context(&krb_context);
87 logit("Cannot initialize krb5 context");
94 /* Check if this user is OK to login. This only works with krb5 - other
95 * GSSAPI mechanisms will need their own.
96 * Returns true if the user is OK to log in, otherwise returns 0
100 ssh_gssapi_krb5_userok(ssh_gssapi_client *client, char *name)
102 krb5_principal princ;
105 if (ssh_gssapi_krb5_init() == 0)
108 if ((retval = krb5_parse_name(krb_context, client->exportedname.value,
110 logit("krb5_parse_name(): %.100s",
111 krb5_get_err_text(krb_context, retval));
114 if (krb5_kuserok(krb_context, princ, name)) {
116 logit("Authorized to %s, krb5 principal %s (krb5_kuserok)",
117 name, (char *)client->displayname.value);
121 krb5_free_principal(krb_context, princ);
126 /* Retrieve the local username associated with a set of Kerberos
127 * credentials. Hopefully we can use this for the 'empty' username
128 * logins discussed in the draft */
130 ssh_gssapi_krb5_localname(ssh_gssapi_client *client, char **user) {
131 krb5_principal princ;
134 if (ssh_gssapi_krb5_init() == 0)
137 if ((retval=krb5_parse_name(krb_context, client->displayname.value,
139 logit("krb5_parse_name(): %.100s",
140 krb5_get_err_text(krb_context,retval));
144 /* We've got to return a malloc'd string */
145 *user = (char *)xmalloc(256);
146 if (krb5_aname_to_localname(krb_context, princ, 256, *user)) {
155 /* This writes out any forwarded credentials from the structure populated
156 * during userauth. Called after we have setuid to the user */
159 ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client)
162 krb5_error_code problem;
163 krb5_principal princ;
164 OM_uint32 maj_status, min_status;
165 gss_cred_id_t krb5_cred_handle;
167 const char* new_ccname;
169 if (client->creds == NULL) {
170 debug("No credentials stored");
174 if (ssh_gssapi_krb5_init() == 0)
178 if ((problem = krb5_cc_gen_new(krb_context, &krb5_fcc_ops, &ccache))) {
179 logit("krb5_cc_gen_new(): %.100s",
180 krb5_get_err_text(krb_context, problem));
184 if ((problem = ssh_krb5_cc_gen(krb_context, &ccache))) {
185 logit("ssh_krb5_cc_gen(): %.100s",
186 krb5_get_err_text(krb_context, problem));
189 #endif /* #ifdef HEIMDAL */
191 if ((problem = krb5_parse_name(krb_context,
192 client->exportedname.value, &princ))) {
193 logit("krb5_parse_name(): %.100s",
194 krb5_get_err_text(krb_context, problem));
195 krb5_cc_destroy(krb_context, ccache);
199 if ((problem = krb5_cc_initialize(krb_context, ccache, princ))) {
200 logit("krb5_cc_initialize(): %.100s",
201 krb5_get_err_text(krb_context, problem));
202 krb5_free_principal(krb_context, princ);
203 krb5_cc_destroy(krb_context, ccache);
207 krb5_free_principal(krb_context, princ);
211 __gss_get_mechanism_cred(client->creds,
212 &(gssapi_kerberos_mech.oid));
214 krb5_cred_handle = client->creds;
217 if ((maj_status = gss_krb5_copy_ccache(&min_status,
218 krb5_cred_handle, ccache))) {
219 logit("gss_krb5_copy_ccache() failed");
220 krb5_cc_destroy(krb_context, ccache);
224 new_ccname = krb5_cc_get_name(krb_context, ccache);
226 client->store.envvar = "KRB5CCNAME";
228 xasprintf(&client->store.envval, "API:%s", new_ccname);
229 client->store.filename = NULL;
231 xasprintf(&client->store.envval, "FILE:%s", new_ccname);
232 client->store.filename = xstrdup(new_ccname);
237 do_pam_putenv(client->store.envvar, client->store.envval);
240 krb5_cc_close(krb_context, ccache);