2 * Copyright (c) 2010 CESNET
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
8 * 1. Redistributions of source code must retain the above copyright notice,
9 * 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 * 3. Neither the name of CESNET nor the names of its contributors may
16 * be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
20 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
23 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
32 #include "mod_auth_gssapi.h"
34 module AP_MODULE_DECLARE_DATA auth_gssapi_module;
36 #define command(name, func, var, type, usage) \
37 AP_INIT_ ## type (name, (void*) func, \
38 (void*)APR_OFFSETOF(gss_auth_config, var), \
39 OR_AUTHCFG | RSRC_CONF, usage)
41 static const command_rec gss_config_cmds[] = {
42 command("GSSServiceName", ap_set_string_slot, service_name,
43 TAKE1, "Service name used for Apache authentication."),
45 command("GSSKrb5Keytab", ap_set_string_slot, krb5_keytab,
46 TAKE1, "Location of Kerberos V5 keytab file."),
48 AP_INIT_RAW_ARGS("GssapiNameAttributes", mag_name_attrs, NULL, OR_AUTHCFG | RSRC_CONF,
49 "Name Attributes to be exported as environ variables"),
54 set_http_headers(request_rec *r, const gss_auth_config *conf,
55 char *negotiate_ret_value)
58 const char *header_name = (r->proxyreq == PROXYREQ_PROXY) ?
59 "Proxy-Authenticate" : "WWW-Authenticate";
61 if (negotiate_ret_value == NULL)
64 negoauth_param = (*negotiate_ret_value == '\0') ? "Negotiate" :
65 apr_pstrcat(r->pool, "Negotiate ", negotiate_ret_value, NULL);
66 apr_table_add(r->err_headers_out, header_name, negoauth_param);
70 gss_authenticate(request_rec *r, gss_auth_config *conf, gss_conn_ctx ctx,
71 const char *auth_line, char **negotiate_ret_value)
73 OM_uint32 major_status, minor_status, minor_status2;
74 gss_buffer_desc input_token = GSS_C_EMPTY_BUFFER;
75 gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER;
76 const char *auth_param = NULL;
78 gss_name_t client_name = GSS_C_NO_NAME;
79 gss_cred_id_t delegated_cred = GSS_C_NO_CREDENTIAL;
80 gss_cred_id_t server_creds = GSS_C_NO_CREDENTIAL;
81 OM_uint32 ret_flags = 0;
82 gss_OID_desc spnego_oid;
83 OM_uint32 (*accept_sec_context)
84 (OM_uint32 *, gss_ctx_id_t *, const gss_cred_id_t,
85 const gss_buffer_t, const gss_channel_bindings_t,
86 gss_name_t *, gss_OID *, gss_buffer_t, OM_uint32 *,
87 OM_uint32 *, gss_cred_id_t *);
89 *negotiate_ret_value = "\0";
91 spnego_oid.length = 6;
92 spnego_oid.elements = (void *)"\x2b\x06\x01\x05\x05\x02";
94 if (conf->krb5_keytab) {
96 /* we don't use the ap_* calls here, since the string passed to putenv()
97 * will become part of the enviroment and shouldn't be free()ed by apache
99 ktname = malloc(strlen("KRB5_KTNAME=") + strlen(conf->krb5_keytab) + 1);
100 if (ktname == NULL) {
101 gss_log(APLOG_MARK, APLOG_ERR, 0, r, "malloc() failed: not enough memory");
102 ret = HTTP_INTERNAL_SERVER_ERROR;
105 sprintf(ktname, "KRB5_KTNAME=%s", conf->krb5_keytab);
108 /* Seems to be also supported by latest MIT */
109 gsskrb5_register_acceptor_identity(conf->krb_5_keytab);
113 /* ap_getword() shifts parameter */
114 auth_param = ap_getword_white(r->pool, &auth_line);
115 if (auth_param == NULL) {
116 gss_log(APLOG_MARK, APLOG_ERR, 0, r,
117 "No Authorization parameter in request from client");
118 ret = HTTP_UNAUTHORIZED;
122 if (ctx->state == GSS_CTX_ESTABLISHED) {
123 gss_delete_sec_context(&minor_status, &ctx->context, GSS_C_NO_BUFFER);
124 ctx->context = GSS_C_NO_CONTEXT;
125 ctx->state = GSS_CTX_EMPTY;
128 input_token.length = apr_base64_decode_len(auth_param) + 1;
129 input_token.value = apr_pcalloc(r->connection->pool, input_token.length);
130 if (input_token.value == NULL) {
131 gss_log(APLOG_MARK, APLOG_ERR, 0, r,
132 "ap_pcalloc() failed (not enough memory)");
133 ret = HTTP_INTERNAL_SERVER_ERROR;
136 input_token.length = apr_base64_decode(input_token.value, auth_param);
138 /* LOG length, type */
140 #ifdef GSSAPI_SUPPORTS_SPNEGO
141 accept_sec_context = gss_accept_sec_context;
143 accept_sec_context = (cmp_gss_type(&input_token, &spnego_oid) == 0) ?
144 gss_accept_sec_context_spnego : gss_accept_sec_context;
147 major_status = accept_sec_context(&minor_status,
151 GSS_C_NO_CHANNEL_BINDINGS,
158 gss_log(APLOG_MARK, APLOG_DEBUG, 0, r,
159 "Client %s us their credential",
160 (ret_flags & GSS_C_DELEG_FLAG) ? "delegated" : "didn't delegate");
161 if (output_token.length) {
165 len = apr_base64_encode_len(output_token.length) + 1;
166 token = apr_pcalloc(r->connection->pool, len + 1);
168 gss_log(APLOG_MARK, APLOG_ERR, 0, r,
169 "ap_pcalloc() failed (not enough memory)");
170 ret = HTTP_INTERNAL_SERVER_ERROR;
171 gss_release_buffer(&minor_status2, &output_token);
174 apr_base64_encode(token, output_token.value, output_token.length);
176 *negotiate_ret_value = token;
177 gss_log(APLOG_MARK, APLOG_DEBUG, 0, r,
178 "GSS-API token of length %d bytes will be sent back",
179 output_token.length);
180 gss_release_buffer(&minor_status2, &output_token);
183 if (GSS_ERROR(major_status)) {
184 // at least this error should be populated, to provider further information
185 // to the user (maybe)
186 char *error = get_gss_error(r, major_status, minor_status, "Failed to establish authentication");
187 apr_table_set(r->subprocess_env, "GSS_ERROR_STR", error);
188 gss_log(APLOG_MARK, APLOG_ERR, 0, r, error);
190 /* Don't offer the Negotiate method again if call to GSS layer failed */
191 /* XXX ... which means we don't return the "error" output */
192 *negotiate_ret_value = NULL;
194 gss_delete_sec_context(&minor_status, &ctx->context, GSS_C_NO_BUFFER);
195 ctx->context = GSS_C_NO_CONTEXT;
196 ctx->state = GSS_CTX_EMPTY;
197 ret = HTTP_UNAUTHORIZED;
201 if (major_status & GSS_S_CONTINUE_NEEDED) {
202 ctx->state = GSS_CTX_IN_PROGRESS;
203 ret = HTTP_UNAUTHORIZED;
207 major_status = gss_inquire_context(&minor_status, ctx->context, &client_name,
208 NULL, NULL, NULL, NULL, NULL, NULL);
209 if (GSS_ERROR(major_status)) {
210 gss_log(APLOG_MARK, APLOG_ERR, 0, r,
211 "%s", get_gss_error(r, major_status, minor_status, "gss_inquire_context() failed"));
212 ret = HTTP_INTERNAL_SERVER_ERROR;
216 major_status = gss_display_name(&minor_status, client_name, &output_token, NULL);
217 ctx->user = apr_pstrndup(r->pool, output_token.value, output_token.length);
219 if (conf->name_attributes) {
220 mag_get_name_attributes(r, conf, client_name, ctx);
221 mag_set_req_data(r, conf, ctx);
225 gss_release_name(&minor_status, &client_name);
226 if (GSS_ERROR(major_status)) {
227 gss_log(APLOG_MARK, APLOG_ERR, 0, r,
228 "%s", get_gss_error(r, major_status, minor_status,
229 "gss_display_name() failed"));
230 ret = HTTP_INTERNAL_SERVER_ERROR;
234 ctx->state = GSS_CTX_ESTABLISHED;
235 gss_release_buffer(&minor_status, &output_token);
241 gss_release_cred(&minor_status, &delegated_cred);
243 if (output_token.length)
244 gss_release_buffer(&minor_status, &output_token);
246 if (client_name != GSS_C_NO_NAME)
247 gss_release_name(&minor_status, &client_name);
249 if (server_creds != GSS_C_NO_CREDENTIAL)
250 gss_release_cred(&minor_status, &server_creds);
255 static int mag_post_config(apr_pool_t *cfgpool, apr_pool_t *log,
256 apr_pool_t *temp, server_rec *s)
258 ap_add_version_component(cfgpool, "Moonshot mod_auth_gssapi");
262 #define MAG_ERROR_NO_AUTH_DATA "NO_AUTH_DATA"
263 #define MAG_ERROR_UNSUP_AUTH_TYPE "UNSUP_AUTH_TYPE"
264 #define MAG_ERROR_GSS_MECH "GSS_MECH_ERROR"
267 gss_authenticate_user(request_rec *r)
269 gss_auth_config *conf =
270 (gss_auth_config *) ap_get_module_config(r->per_dir_config,
271 &auth_gssapi_module);
272 const char *auth_line = NULL;
273 const char *type = NULL;
274 char *auth_type = NULL;
275 char *negotiate_ret_value = NULL;
276 gss_conn_ctx conn_ctx = NULL;
279 gss_log(APLOG_MARK, APLOG_DEBUG, 0, r, "Entering GSSAPI authentication");
281 /* get the type specified in Apache configuration */
282 type = ap_auth_type(r);
283 if (type == NULL || strcmp(type, "Negotiate") != 0) {
284 gss_log(APLOG_MARK, APLOG_DEBUG, 0, r,
285 "AuthType '%s' is not for us, bailing out",
286 (type) ? type : "(NULL)");
291 /* get what the user sent us in the HTTP header */
292 auth_line = apr_table_get(r->headers_in, (r->proxyreq == PROXYREQ_PROXY)
293 ? "Proxy-Authorization"
295 if (auth_line == NULL) {
296 gss_log(APLOG_MARK, APLOG_DEBUG, 0, r,
297 "Client hasn't sent any authentication data, giving up");
298 set_http_headers(r, conf, "\0");
299 apr_table_set(r->subprocess_env, "MAG_ERROR", MAG_ERROR_NO_AUTH_DATA);
300 return HTTP_UNAUTHORIZED;
303 auth_type = ap_getword_white(r->pool, &auth_line);
304 if (strcasecmp(auth_type, "Negotiate") != 0) {
305 gss_log(APLOG_MARK, APLOG_DEBUG, 0, r,
306 "Unsupported authentication type (%s) requested by client",
307 (auth_type) ? auth_type : "(NULL)");
308 set_http_headers(r, conf, "\0");
309 apr_table_set(r->subprocess_env, "MAG_ERROR", MAG_ERROR_UNSUP_AUTH_TYPE);
310 return HTTP_UNAUTHORIZED;
313 if ((NULL == (conn_ctx = gss_retrieve_conn_ctx(r))) &&
314 (NULL == (conn_ctx = gss_create_conn_ctx(r, conf)))) {
315 gss_log(APLOG_MARK, APLOG_ERR, 0, r,
316 "Failed to create internal context: probably not enough memory");
317 return HTTP_INTERNAL_SERVER_ERROR;
320 /* optimizing hack */
321 if (conn_ctx->state == GSS_CTX_ESTABLISHED && auth_line == NULL) {
322 r->user = apr_pstrdup(r->pool, conn_ctx->user);
323 r->ap_auth_type = "Negotiate";
327 /* XXXX subrequests ignored, only successful accesses taken into account! */
328 if (!ap_is_initial_req(r) && conn_ctx->state == GSS_CTX_ESTABLISHED) {
329 r->user = apr_pstrdup(r->pool, conn_ctx->user);
330 r->ap_auth_type = "Negotiate";
334 ret = gss_authenticate(r, conf, conn_ctx,
335 auth_line, &negotiate_ret_value);
336 if (ret == HTTP_UNAUTHORIZED || ret == OK) {
338 set_http_headers(r, conf, negotiate_ret_value);
342 r->user = apr_pstrdup(r->pool, conn_ctx->user);
343 r->ap_auth_type = "Negotiate";
345 apr_table_set(r->subprocess_env, "MAG_ERROR", MAG_ERROR_GSS_MECH);
353 gss_register_hooks(apr_pool_t *p)
355 ap_hook_check_user_id(gss_authenticate_user, NULL, NULL, APR_HOOK_MIDDLE);
356 ap_hook_post_config(mag_post_config, NULL, NULL, APR_HOOK_MIDDLE);
359 module AP_MODULE_DECLARE_DATA auth_gssapi_module = {
360 STANDARD20_MODULE_STUFF,
361 gss_config_dir_create,