4 Copyright (C) 2014 Simo Sorce <simo@redhat.com>
6 Permission is hereby granted, free of charge, to any person obtaining a
7 copy of this software and associated documentation files (the "Software"),
8 to deal in the Software without restriction, including without limitation
9 the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 and/or sell copies of the Software, and to permit persons to whom the
11 Software is furnished to do so, subject to the following conditions:
13 The above copyright notice and this permission notice shall be included in
14 all copies or substantial portions of the Software.
16 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 DEALINGS IN THE SOFTWARE.
25 #include "mod_auth_gssapi.h"
27 #define MOD_AUTH_GSSAPI_VERSION PACKAGE_NAME "/" PACKAGE_VERSION
29 module AP_MODULE_DECLARE_DATA auth_gssapi_module;
31 APLOG_USE_MODULE(auth_gssapi);
33 APR_DECLARE_OPTIONAL_FN(int, ssl_is_https, (conn_rec *));
35 static char *mag_status(request_rec *req, int type, uint32_t err)
37 uint32_t maj_ret, min_ret;
46 maj_ret = gss_display_status(&min_ret, err, type,
47 GSS_C_NO_OID, &msg_ctx, &text);
48 if (maj_ret != GSS_S_COMPLETE) {
54 msg_ret = apr_psprintf(req->pool, "%s, %*s",
55 msg_ret, len, (char *)text.value);
57 msg_ret = apr_psprintf(req->pool, "%*s", len, (char *)text.value);
59 gss_release_buffer(&min_ret, &text);
60 } while (msg_ctx != 0);
65 static char *mag_error(request_rec *req, const char *msg,
66 uint32_t maj, uint32_t min)
71 msg_maj = mag_status(req, GSS_C_GSS_CODE, maj);
72 msg_min = mag_status(req, GSS_C_MECH_CODE, min);
73 return apr_psprintf(req->pool, "%s: [%s (%s)]", msg, msg_maj, msg_min);
76 static APR_OPTIONAL_FN_TYPE(ssl_is_https) *mag_is_https = NULL;
78 static int mag_post_config(apr_pool_t *cfgpool, apr_pool_t *log,
79 apr_pool_t *temp, server_rec *s)
81 /* FIXME: create mutex to deal with connections and contexts ? */
82 mag_is_https = APR_RETRIEVE_OPTIONAL_FN(ssl_is_https);
83 mag_post_config_session();
84 ap_add_version_component(cfgpool, MOD_AUTH_GSSAPI_VERSION);
89 static int mag_pre_connection(conn_rec *c, void *csd)
93 mc = apr_pcalloc(c->pool, sizeof(struct mag_conn));
94 if (!mc) return DECLINED;
97 ap_set_module_config(c->conn_config, &auth_gssapi_module, (void*)mc);
101 static apr_status_t mag_conn_destroy(void *ptr)
103 struct mag_conn *mc = (struct mag_conn *)ptr;
107 (void)gss_delete_sec_context(&min, &mc->ctx, GSS_C_NO_BUFFER);
108 mc->established = false;
113 static bool mag_conn_is_https(conn_rec *c)
116 if (mag_is_https(c)) return true;
122 static void mag_store_deleg_creds(request_rec *req,
123 char *dir, char *clientname,
124 gss_cred_id_t delegated_cred,
127 gss_key_value_element_desc element;
128 gss_key_value_set_desc store;
132 value = apr_psprintf(req->pool, "FILE:%s/%s", dir, clientname);
134 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, NULL,
135 "OOM storing delegated credentials");
139 element.key = "ccache";
140 element.value = value;
141 store.elements = &element;
144 maj = gss_store_cred_into(&min, delegated_cred, GSS_C_INITIATE,
145 GSS_C_NULL_OID, 1, 1, &store, NULL, NULL);
146 if (GSS_ERROR(maj)) {
147 ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req, "%s",
148 mag_error(req, "failed to store delegated creds",
155 static int mag_auth(request_rec *req)
158 struct mag_config *cfg;
159 const char *auth_header;
160 char *auth_header_type;
161 char *auth_header_value;
162 int ret = HTTP_UNAUTHORIZED;
163 gss_ctx_id_t ctx = GSS_C_NO_CONTEXT;
165 gss_buffer_desc input = GSS_C_EMPTY_BUFFER;
166 gss_buffer_desc output = GSS_C_EMPTY_BUFFER;
167 gss_buffer_desc name = GSS_C_EMPTY_BUFFER;
168 gss_name_t client = GSS_C_NO_NAME;
169 gss_cred_id_t acquired_cred = GSS_C_NO_CREDENTIAL;
170 gss_cred_id_t delegated_cred = GSS_C_NO_CREDENTIAL;
171 gss_cred_usage_t cred_usage = GSS_C_ACCEPT;
178 gss_OID mech_type = GSS_C_NO_OID;
179 gss_buffer_desc lname = GSS_C_EMPTY_BUFFER;
180 struct mag_conn *mc = NULL;
182 type = ap_auth_type(req);
183 if ((type == NULL) || (strcasecmp(type, "GSSAPI") != 0)) {
187 /* ignore auth for subrequests */
188 if (!ap_is_initial_req(req)) {
192 cfg = ap_get_module_config(req->per_dir_config, &auth_gssapi_module);
195 if (!mag_conn_is_https(req->connection)) {
196 ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
197 "Not a TLS connection, refusing to authenticate!");
202 if (cfg->gss_conn_ctx) {
203 mc = (struct mag_conn *)ap_get_module_config(
204 req->connection->conn_config,
205 &auth_gssapi_module);
207 ap_log_rerror(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, req,
208 "Failed to retrieve connection context!");
213 /* if available, session always supersedes connection bound data */
214 if (cfg->use_sessions) {
215 mag_check_session(req, cfg, &mc);
219 /* register the context in the memory pool, so it can be freed
220 * when the connection/request is terminated */
221 apr_pool_userdata_set(mc, "mag_conn_ptr",
222 mag_conn_destroy, mc->parent);
224 if (mc->established) {
225 ap_log_rerror(APLOG_MARK, APLOG_DEBUG|APLOG_NOERRNO, 0, req,
226 "Already established context found!");
227 apr_table_set(req->subprocess_env, "GSS_NAME", mc->gss_name);
228 req->ap_auth_type = apr_pstrdup(req->pool, "Negotiate");
229 req->user = apr_pstrdup(req->pool, mc->user_name);
238 auth_header = apr_table_get(req->headers_in, "Authorization");
239 if (!auth_header) goto done;
241 auth_header_type = ap_getword_white(req->pool, &auth_header);
242 if (!auth_header_type) goto done;
244 if (strcasecmp(auth_header_type, "Negotiate") != 0) goto done;
246 auth_header_value = ap_getword_white(req->pool, &auth_header);
247 if (!auth_header_value) goto done;
248 input.length = apr_base64_decode_len(auth_header_value) + 1;
249 input.value = apr_pcalloc(req->pool, input.length);
250 if (!input.value) goto done;
251 input.length = apr_base64_decode(input.value, auth_header_value);
253 #ifdef HAVE_GSS_ACQUIRE_CRED_FROM
254 if (cfg->use_s4u2proxy) {
255 cred_usage = GSS_C_BOTH;
257 if (cfg->cred_store) {
258 maj = gss_acquire_cred_from(&min, GSS_C_NO_NAME, 0,
259 GSS_C_NO_OID_SET, cred_usage,
260 cfg->cred_store, &acquired_cred,
262 if (GSS_ERROR(maj)) {
263 ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req, "%s",
264 mag_error(req, "gss_acquire_cred_from() failed",
271 maj = gss_accept_sec_context(&min, pctx, acquired_cred,
272 &input, GSS_C_NO_CHANNEL_BINDINGS,
273 &client, &mech_type, &output, &flags, &vtime,
275 if (GSS_ERROR(maj)) {
276 ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req, "%s",
277 mag_error(req, "gss_accept_sec_context() failed",
282 if (maj == GSS_S_CONTINUE_NEEDED) {
284 ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req,
285 "Mechanism needs continuation but neither "
286 "GssapiConnectionBound nor "
287 "GssapiUseSessions are available");
288 gss_delete_sec_context(&min, pctx, GSS_C_NO_BUFFER);
289 gss_release_buffer(&min, &output);
292 /* auth not complete send token and wait next packet */
296 req->ap_auth_type = apr_pstrdup(req->pool, "Negotiate");
298 /* Always set the GSS name in an env var */
299 maj = gss_display_name(&min, client, &name, NULL);
300 if (GSS_ERROR(maj)) {
301 ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req, "%s",
302 mag_error(req, "gss_display_name() failed",
306 clientname = apr_pstrndup(req->pool, name.value, name.length);
307 apr_table_set(req->subprocess_env, "GSS_NAME", clientname);
309 #ifdef HAVE_GSS_STORE_CRED_INTO
310 if (cfg->deleg_ccache_dir && delegated_cred != GSS_C_NO_CREDENTIAL) {
311 char *ccachefile = NULL;
313 mag_store_deleg_creds(req, cfg->deleg_ccache_dir, clientname,
314 delegated_cred, &ccachefile);
317 apr_table_set(req->subprocess_env, "KRB5CCNAME", ccachefile);
322 if (cfg->map_to_local) {
323 maj = gss_localname(&min, client, mech_type, &lname);
324 if (maj != GSS_S_COMPLETE) {
325 ap_log_rerror(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, req, "%s",
326 mag_error(req, "gss_localname() failed", maj, min));
329 req->user = apr_pstrndup(req->pool, lname.value, lname.length);
331 req->user = clientname;
335 mc->user_name = apr_pstrdup(mc->parent, req->user);
336 mc->gss_name = apr_pstrdup(mc->parent, clientname);
337 mc->established = true;
338 if (vtime == GSS_C_INDEFINITE || vtime < MIN_SESS_EXP_TIME) {
339 vtime = MIN_SESS_EXP_TIME;
341 mc->expiration = time(NULL) + vtime;
342 if (cfg->use_sessions) {
343 mag_attempt_session(req, cfg, mc);
350 if (ret == HTTP_UNAUTHORIZED) {
351 if (output.length != 0) {
352 replen = apr_base64_encode_len(output.length) + 1;
353 reply = apr_pcalloc(req->pool, 10 + replen);
355 memcpy(reply, "Negotiate ", 10);
356 apr_base64_encode(&reply[10], output.value, output.length);
357 apr_table_add(req->err_headers_out,
358 "WWW-Authenticate", reply);
361 apr_table_add(req->err_headers_out,
362 "WWW-Authenticate", "Negotiate");
365 gss_release_cred(&min, &delegated_cred);
366 gss_release_buffer(&min, &output);
367 gss_release_name(&min, &client);
368 gss_release_buffer(&min, &name);
369 gss_release_buffer(&min, &lname);
374 static void *mag_create_dir_config(apr_pool_t *p, char *dir)
376 struct mag_config *cfg;
378 cfg = (struct mag_config *)apr_pcalloc(p, sizeof(struct mag_config));
379 if (!cfg) return NULL;
385 static const char *mag_ssl_only(cmd_parms *parms, void *mconfig, int on)
387 struct mag_config *cfg = (struct mag_config *)mconfig;
388 cfg->ssl_only = on ? true : false;
392 static const char *mag_map_to_local(cmd_parms *parms, void *mconfig, int on)
394 struct mag_config *cfg = (struct mag_config *)mconfig;
395 cfg->map_to_local = on ? true : false;
399 static const char *mag_conn_ctx(cmd_parms *parms, void *mconfig, int on)
401 struct mag_config *cfg = (struct mag_config *)mconfig;
402 cfg->gss_conn_ctx = on ? true : false;
406 static const char *mag_use_sess(cmd_parms *parms, void *mconfig, int on)
408 struct mag_config *cfg = (struct mag_config *)mconfig;
409 cfg->use_sessions = on ? true : false;
413 static const char *mag_use_s4u2p(cmd_parms *parms, void *mconfig, int on)
415 struct mag_config *cfg = (struct mag_config *)mconfig;
416 cfg->use_s4u2proxy = on ? true : false;
418 if (cfg->deleg_ccache_dir == NULL) {
419 cfg->deleg_ccache_dir = apr_pstrdup(parms->pool, "/tmp");
420 if (!cfg->deleg_ccache_dir) {
421 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0,
422 parms->server, "%s", "OOM setting deleg_ccache_dir.");
428 static const char *mag_sess_key(cmd_parms *parms, void *mconfig, const char *w)
430 struct mag_config *cfg = (struct mag_config *)mconfig;
437 if (strncmp(w, "key:", 4) != 0) {
438 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
439 "Invalid key format, expected prefix 'key:'");
444 l = apr_base64_decode_len(k);
445 val = apr_palloc(parms->temp_pool, l);
447 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
448 "Failed to get memory to decode key");
452 keys.length = (int)apr_base64_decode_binary(val, k);
453 keys.value = (unsigned char *)val;
455 if (keys.length != 32) {
456 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
457 "Invalid key lenght, expected 32 got %d", keys.length);
461 rc = SEAL_KEY_CREATE(cfg->pool, &cfg->mag_skey, &keys);
463 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
464 "Failed to import sealing key!");
469 #define MAX_CRED_OPTIONS 10
471 static const char *mag_cred_store(cmd_parms *parms, void *mconfig,
474 struct mag_config *cfg = (struct mag_config *)mconfig;
475 gss_key_value_element_desc *elements;
484 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
485 "%s [%s]", "Invalid syntax for GssapiCredStore option", w);
489 key = apr_pstrndup(parms->pool, w, (p-w));
490 value = apr_pstrdup(parms->pool, p + 1);
491 if (!key || !value) {
492 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
493 "%s", "OOM handling GssapiCredStore option");
497 if (!cfg->cred_store) {
498 cfg->cred_store = apr_pcalloc(parms->pool,
499 sizeof(gss_key_value_set_desc));
500 if (!cfg->cred_store) {
501 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
502 "%s", "OOM handling GssapiCredStore option");
505 size = sizeof(gss_key_value_element_desc) * MAX_CRED_OPTIONS;
506 cfg->cred_store->elements = apr_palloc(parms->pool, size);
507 if (!cfg->cred_store->elements) {
508 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
509 "%s", "OOM handling GssapiCredStore option");
513 elements = cfg->cred_store->elements;
514 count = cfg->cred_store->count;
516 if (count >= MAX_CRED_OPTIONS) {
517 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
518 "Too many GssapiCredStore options (MAX: %d)",
522 cfg->cred_store->count++;
524 elements[count].key = key;
525 elements[count].value = value;
530 static const char *mag_deleg_ccache_dir(cmd_parms *parms, void *mconfig,
533 struct mag_config *cfg = (struct mag_config *)mconfig;
535 cfg->deleg_ccache_dir = apr_pstrdup(parms->pool, value);
536 if (!cfg->deleg_ccache_dir) {
537 ap_log_error(APLOG_MARK, APLOG_ERR|APLOG_NOERRNO, 0, parms->server,
538 "%s", "OOM handling GssapiDelegCcacheDir option");
544 static const command_rec mag_commands[] = {
545 AP_INIT_FLAG("GssapiSSLonly", mag_ssl_only, NULL, OR_AUTHCFG,
546 "Work only if connection is SSL Secured"),
547 AP_INIT_FLAG("GssapiLocalName", mag_map_to_local, NULL, OR_AUTHCFG,
548 "Translate principals to local names"),
549 AP_INIT_FLAG("GssapiConnectionBound", mag_conn_ctx, NULL, OR_AUTHCFG,
550 "Authentication is bound to the TCP connection"),
551 AP_INIT_FLAG("GssapiUseSessions", mag_use_sess, NULL, OR_AUTHCFG,
552 "Authentication uses mod_sessions to hold status"),
553 AP_INIT_RAW_ARGS("GssapiSessionKey", mag_sess_key, NULL, OR_AUTHCFG,
554 "Key Used to seal session data."),
555 #ifdef HAVE_GSS_ACQUIRE_CRED_FROM
556 AP_INIT_FLAG("GssapiUseS4U2Proxy", mag_use_s4u2p, NULL, OR_AUTHCFG,
557 "Initializes credentials for s4u2proxy usage"),
559 #ifdef HAVE_GSS_STORE_CRED_INTO
560 AP_INIT_ITERATE("GssapiCredStore", mag_cred_store, NULL, OR_AUTHCFG,
562 AP_INIT_RAW_ARGS("GssapiDelegCcacheDir", mag_deleg_ccache_dir, NULL,
563 OR_AUTHCFG, "Directory to store delegated credentials"),
569 mag_register_hooks(apr_pool_t *p)
571 ap_hook_check_user_id(mag_auth, NULL, NULL, APR_HOOK_MIDDLE);
572 ap_hook_post_config(mag_post_config, NULL, NULL, APR_HOOK_MIDDLE);
573 ap_hook_pre_connection(mag_pre_connection, NULL, NULL, APR_HOOK_MIDDLE);
576 module AP_MODULE_DECLARE_DATA auth_gssapi_module =
578 STANDARD20_MODULE_STUFF,
579 mag_create_dir_config,