1 /* $OpenBSD: gss-serv-krb5.c,v 1.4 2005/10/13 19:08:08 stevesk 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.
39 extern ServerOptions options;
43 #elif !defined(MECHGLUE)
44 # ifdef HAVE_GSSAPI_KRB5_H
45 # include <gssapi_krb5.h>
46 # elif HAVE_GSSAPI_GSSAPI_KRB5_H
47 # include <gssapi/gssapi_krb5.h>
51 static krb5_context krb_context = NULL;
52 static int ssh_gssapi_krb5_init();
53 static int ssh_gssapi_krb5_userok(ssh_gssapi_client *client, char *name);
54 static int ssh_gssapi_krb5_localname(ssh_gssapi_client *client, char **user);
55 static void ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client);
57 ssh_gssapi_mech gssapi_kerberos_mech = {
58 "toWM5Slw5Ew8Mqkay+al2g==",
60 {9, "\x2A\x86\x48\x86\xF7\x12\x01\x02\x02"},
62 &ssh_gssapi_krb5_userok,
63 &ssh_gssapi_krb5_localname,
64 &ssh_gssapi_krb5_storecreds
67 /* Initialise the krb5 library, for the stuff that GSSAPI won't do */
70 ssh_gssapi_krb5_init(void)
72 krb5_error_code problem;
74 if (krb_context != NULL)
77 problem = krb5_init_context(&krb_context);
79 logit("Cannot initialize krb5 context");
86 /* Check if this user is OK to login. This only works with krb5 - other
87 * GSSAPI mechanisms will need their own.
88 * Returns true if the user is OK to log in, otherwise returns 0
92 ssh_gssapi_krb5_userok(ssh_gssapi_client *client, char *name)
97 if (ssh_gssapi_krb5_init() == 0)
100 if ((retval = krb5_parse_name(krb_context, client->exportedname.value,
102 logit("krb5_parse_name(): %.100s",
103 krb5_get_err_text(krb_context, retval));
106 if (krb5_kuserok(krb_context, princ, name)) {
108 logit("Authorized to %s, krb5 principal %s (krb5_kuserok)",
109 name, (char *)client->displayname.value);
113 krb5_free_principal(krb_context, princ);
118 /* Retrieve the local username associated with a set of Kerberos
119 * credentials. Hopefully we can use this for the 'empty' username
120 * logins discussed in the draft */
122 ssh_gssapi_krb5_localname(ssh_gssapi_client *client, char **user) {
123 krb5_principal princ;
126 if (ssh_gssapi_krb5_init() == 0)
129 if ((retval=krb5_parse_name(krb_context, client->displayname.value,
131 logit("krb5_parse_name(): %.100s",
132 krb5_get_err_text(krb_context,retval));
136 /* We've got to return a malloc'd string */
137 *user = (char *)xmalloc(256);
138 if (krb5_aname_to_localname(krb_context, princ, 256, *user)) {
147 /* This writes out any forwarded credentials from the structure populated
148 * during userauth. Called after we have setuid to the user */
151 ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client)
154 krb5_error_code problem;
155 krb5_principal princ;
156 OM_uint32 maj_status, min_status;
157 gss_cred_id_t krb5_cred_handle;
160 if (client->creds == NULL) {
161 debug("No credentials stored");
165 if (ssh_gssapi_krb5_init() == 0)
169 if ((problem = krb5_cc_gen_new(krb_context, &krb5_fcc_ops, &ccache))) {
170 logit("krb5_cc_gen_new(): %.100s",
171 krb5_get_err_text(krb_context, problem));
175 if ((problem = ssh_krb5_cc_gen(krb_context, &ccache))) {
176 logit("ssh_krb5_cc_gen(): %.100s",
177 krb5_get_err_text(krb_context, problem));
180 #endif /* #ifdef HEIMDAL */
182 if ((problem = krb5_parse_name(krb_context,
183 client->exportedname.value, &princ))) {
184 logit("krb5_parse_name(): %.100s",
185 krb5_get_err_text(krb_context, problem));
186 krb5_cc_destroy(krb_context, ccache);
190 if ((problem = krb5_cc_initialize(krb_context, ccache, princ))) {
191 logit("krb5_cc_initialize(): %.100s",
192 krb5_get_err_text(krb_context, problem));
193 krb5_free_principal(krb_context, princ);
194 krb5_cc_destroy(krb_context, ccache);
198 krb5_free_principal(krb_context, princ);
202 __gss_get_mechanism_cred(client->creds,
203 &(gssapi_kerberos_mech.oid));
205 krb5_cred_handle = client->creds;
208 if ((maj_status = gss_krb5_copy_ccache(&min_status,
209 krb5_cred_handle, ccache))) {
210 logit("gss_krb5_copy_ccache() failed");
211 krb5_cc_destroy(krb_context, ccache);
215 client->store.filename = xstrdup(krb5_cc_get_name(krb_context, ccache));
216 client->store.envvar = "KRB5CCNAME";
217 len = strlen(client->store.filename) + 6;
218 client->store.envval = xmalloc(len);
219 snprintf(client->store.envval, len, "FILE:%s", client->store.filename);
223 do_pam_putenv(client->store.envvar, client->store.envval);
226 krb5_cc_close(krb_context, ccache);