2 * Daniel Kouril <kouril@users.sourceforge.net>
4 * Source and Documentation can be found at:
5 * http://modauthkerb.sourceforge.net/
8 * James E. Robinson, III <james@ncstate.net>
9 * Daniel Henninger <daniel@ncsu.edu>
10 * Ludek Sulak <xsulak@fi.muni.cz>
14 * Copyright (c) 2004 Masarykova universita
15 * (Masaryk University, Brno, Czech Republic)
16 * All rights reserved.
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions are met:
21 * 1. Redistributions of source code must retain the above copyright notice,
22 * this list of conditions and the following disclaimer.
24 * 2. Redistributions in binary form must reproduce the above copyright
25 * notice, this list of conditions and the following disclaimer in the
26 * documentation and/or other materials provided with the distribution.
28 * 3. Neither the name of the University nor the names of its contributors may
29 * be used to endorse or promote products derived from this software
30 * without specific prior written permission.
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
33 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
36 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
37 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
38 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
39 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
40 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
41 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGE.
53 #define MODAUTHKERB_VERSION "5.0-rc6"
54 #define MECH_NEGOTIATE "Negotiate"
57 #include <http_config.h>
58 #include <http_core.h>
60 #include <http_protocol.h>
61 #include <http_request.h>
63 #ifdef STANDARD20_MODULE_STUFF
64 #include <ap_compat.h>
65 #include <apr_strings.h>
66 #include <apr_base64.h>
74 # include <gssapi/gssapi.h>
75 # include <gssapi/gssapi_generic.h>
76 # include <gssapi/gssapi_krb5.h>
77 # define GSS_C_NT_USER_NAME gss_nt_user_name
78 # define GSS_C_NT_HOSTBASED_SERVICE gss_nt_service_name
79 # define krb5_get_err_text(context,code) error_message(code)
81 #include "spnegokrb5.h"
85 /* Prevent warning about closesocket redefinition (Apache's ap_config.h and
86 * MIT Kerberos' port-sockets.h both define it as close) */
91 #include <netdb.h> /* gethostbyname() */
95 #define vsnprintf _vsnprintf
96 #define snprintf _snprintf
98 /* XXX remove dependency on unistd.h ??? */
102 #ifdef STANDARD20_MODULE_STUFF
103 module AP_MODULE_DECLARE_DATA auth_kerb_module;
105 module auth_kerb_module;
108 /***************************************************************************
109 Macros To Ease Compatibility
110 ***************************************************************************/
111 #ifdef STANDARD20_MODULE_STUFF
112 #define MK_POOL apr_pool_t
113 #define MK_TABLE_GET apr_table_get
114 #define MK_USER r->user
115 #define MK_AUTH_TYPE r->ap_auth_type
118 #define MK_TABLE_GET ap_table_get
119 #define MK_USER r->connection->user
120 #define MK_AUTH_TYPE r->connection->ap_auth_type
121 #define PROXYREQ_PROXY STD_PROXY
124 /***************************************************************************
125 Auth Configuration Structure
126 ***************************************************************************/
128 char *krb_auth_realms;
129 int krb_save_credentials;
131 char *krb_service_name;
132 int krb_authoritative;
133 int krb_delegate_basic;
136 int krb_method_gssapi;
137 int krb_method_k5pass;
141 int krb_method_k4pass;
146 set_kerb_auth_headers(request_rec *r, const kerb_auth_config *conf,
147 int use_krb4, int use_krb5pwd, char *negotiate_ret_value);
150 krb5_save_realms(cmd_parms *cmd, kerb_auth_config *sec, char *arg);
152 #ifdef STANDARD20_MODULE_STUFF
153 #define command(name, func, var, type, usage) \
154 AP_INIT_ ## type (name, func, \
155 (void*)APR_XtOffsetOf(kerb_auth_config, var), \
156 OR_AUTHCFG | RSRC_CONF, usage)
158 #define command(name, func, var, type, usage) \
160 (void*)XtOffsetOf(kerb_auth_config, var), \
161 OR_AUTHCFG | RSRC_CONF, type, usage }
164 static const command_rec kerb_auth_cmds[] = {
165 command("KrbAuthRealms", krb5_save_realms, krb_auth_realms,
166 RAW_ARGS, "Realms to attempt authentication against (can be multiple)."),
168 command("KrbAuthRealm", krb5_save_realms, krb_auth_realms,
169 RAW_ARGS, "Alias for KrbAuthRealms."),
171 command("KrbSaveCredentials", ap_set_flag_slot, krb_save_credentials,
172 FLAG, "Save and store credentials/tickets retrieved during auth."),
174 command("KrbVerifyKDC", ap_set_flag_slot, krb_verify_kdc,
175 FLAG, "Verify tickets against keytab to prevent KDC spoofing attacks."),
177 command("KrbServiceName", ap_set_string_slot, krb_service_name,
178 TAKE1, "Service name to be used by Apache for authentication."),
180 command("KrbAuthoritative", ap_set_flag_slot, krb_authoritative,
181 FLAG, "Set to 'off' to allow access control to be passed along to lower modules iff the UserID is not known to this module."),
183 command("KrbDelegateBasic", ap_set_flag_slot, krb_delegate_basic,
184 FLAG, "Always offer Basic authentication regardless of KrbMethodK5Pass and pass on authentication to lower modules if Basic headers arrive."),
187 command("Krb5Keytab", ap_set_file_slot, krb_5_keytab,
188 TAKE1, "Location of Kerberos V5 keytab file."),
190 command("KrbMethodNegotiate", ap_set_flag_slot, krb_method_gssapi,
191 FLAG, "Enable Negotiate authentication method."),
193 command("KrbMethodK5Passwd", ap_set_flag_slot, krb_method_k5pass,
194 FLAG, "Enable Kerberos V5 password authentication."),
198 command("Krb4Srvtab", ap_set_file_slot, krb_4_srvtab,
199 TAKE1, "Location of Kerberos V4 srvtab file."),
201 command("KrbMethodK4Passwd", ap_set_flag_slot, krb_method_k4pass,
202 FLAG, "Enable Kerberos V4 password authentication."),
210 mkstemp(char *template)
215 start = strlen(template) - 1;
216 while(template[start] == 'X') {
217 template[start] = '0' + val % 10;
224 fd = open(template, O_RDWR | O_CREAT | O_EXCL, 0600);
225 if(fd >= 0 || errno != EEXIST)
232 if(template[i] == '9' + 1)
234 if(template[i] <= 'z')
243 #if defined(KRB5) && !defined(HEIMDAL)
244 /* Needed to work around problems with replay caches */
245 #include "mit-internals.h"
247 /* This is our replacement krb5_rc_store function */
248 static krb5_error_code
249 mod_auth_kerb_rc_store(krb5_context context, krb5_rcache rcache,
250 krb5_donot_replay_internal *donot_replay)
255 /* And this is the operations vector for our replay cache */
256 const krb5_rc_ops_internal mod_auth_kerb_rc_ops = {
263 mod_auth_kerb_rc_store,
265 krb5_rc_dfl_get_span,
266 krb5_rc_dfl_get_name,
272 /***************************************************************************
273 Auth Configuration Initialization
274 ***************************************************************************/
275 static void *kerb_dir_create_config(MK_POOL *p, char *d)
277 kerb_auth_config *rec;
279 rec = (kerb_auth_config *) ap_pcalloc(p, sizeof(kerb_auth_config));
280 ((kerb_auth_config *)rec)->krb_verify_kdc = 1;
281 ((kerb_auth_config *)rec)->krb_service_name = "HTTP";
282 ((kerb_auth_config *)rec)->krb_authoritative = 1;
283 ((kerb_auth_config *)rec)->krb_delegate_basic = 0;
285 ((kerb_auth_config *)rec)->krb_method_k5pass = 1;
286 ((kerb_auth_config *)rec)->krb_method_gssapi = 1;
289 ((kerb_auth_config *)rec)->krb_method_k4pass = 1;
295 krb5_save_realms(cmd_parms *cmd, kerb_auth_config *sec, char *arg)
297 sec->krb_auth_realms= ap_pstrdup(cmd->pool, arg);
301 void log_rerror(const char *file, int line, int level, int status,
302 const request_rec *r, const char *fmt, ...)
308 vsnprintf(errstr, sizeof(errstr), fmt, ap);
312 #ifdef STANDARD20_MODULE_STUFF
313 ap_log_rerror(file, line, level | APLOG_NOERRNO, status, r, "%s", errstr);
315 ap_log_rerror(file, line, level | APLOG_NOERRNO, r, "%s", errstr);
320 /***************************************************************************
321 Username/Password Validation for Krb4
322 ***************************************************************************/
324 verify_krb4_user(request_rec *r, char *name, char *instance, char *realm,
325 char *password, char *linstance, char *srvtab, int krb_verify_kdc)
331 const char *hostname;
334 char lrealm[REALM_SZ];
336 ret = krb_get_pw_in_tkt(name, instance, realm, "krbtgt", realm,
337 DEFAULT_TKT_LIFE, password);
339 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
340 "Cannot get krb4 ticket: krb_get_pw_in_tkt() failed: %s",
341 krb_get_err_text(ret));
348 hostname = ap_get_server_name(r);
350 hp = gethostbyname(hostname);
353 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
354 "Cannot verify krb4 ticket: gethostbyname() failed: %s",
358 memcpy(&addr, hp->h_addr, sizeof(addr));
360 phost = krb_get_phost((char *)hostname);
362 krb_get_lrealm(lrealm, 1);
364 ret = krb_mk_req(&ticket, linstance, phost, lrealm, 0);
366 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
367 "Cannot verify krb4 ticket: krb_mk_req() failed: %s",
368 krb_get_err_text(ret));
373 ret = krb_rd_req(&ticket, linstance, phost, addr, &authdata, srvtab);
375 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
376 "Cannot verify krb4 ticket: krb_rd_req() failed: %s",
377 krb_get_err_text(ret));
385 krb4_cache_cleanup(void *data)
387 char *tkt_file = (char *) data;
389 krb_set_tkt_string(tkt_file);
395 authenticate_user_krb4pwd(request_rec *r,
396 kerb_auth_config *conf,
397 const char *auth_line)
401 const char *sent_name;
404 char *tkt_file_p = NULL;
409 char lrealm[REALM_SZ];
410 int all_principals_unkown;
412 sent_pw = ap_pbase64decode(r->pool, auth_line);
413 sent_name = ap_getword (r->pool, &sent_pw, ':');
415 /* do not allow user to override realm setting of server */
416 if (strchr(sent_name, '@')) {
417 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
418 "specifying realm in user name is prohibited");
419 return HTTP_UNAUTHORIZED;
422 sent_instance = strchr(sent_name, '.');
424 *sent_instance++ = '\0';
426 snprintf(tkt_file, sizeof(tkt_file), "/tmp/apache_tkt_XXXXXX");
427 fd = mkstemp(tkt_file);
429 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
430 "Cannot create krb4 ccache: mkstemp() failed: %s",
432 return HTTP_INTERNAL_SERVER_ERROR;
435 tkt_file_p = ap_pstrdup(r->pool, tkt_file);
436 ap_register_cleanup(r->pool, tkt_file_p,
437 krb4_cache_cleanup, ap_null_cleanup);
439 krb_set_tkt_string(tkt_file);
441 all_principals_unkown = 1;
442 realms = conf->krb_auth_realms;
444 memset(lrealm, 0, sizeof(lrealm));
447 realm = ap_getword_white(r->pool, &realms);
450 ret = krb_get_lrealm(lrealm, 1);
456 ret = verify_krb4_user(r, (char *)sent_name,
457 (sent_instance) ? sent_instance : "",
458 (char *)realm, (char *)sent_pw,
459 conf->krb_service_name,
460 conf->krb_4_srvtab, conf->krb_verify_kdc);
461 if (!conf->krb_authoritative && ret) {
462 /* if we're not authoritative, we allow authentication to pass on
463 * to another modules if (and only if) the user is not known to us */
464 if (all_principals_unkown && ret != KDC_PR_UNKNOWN)
465 all_principals_unkown = 0;
470 } while (realms && *realms);
473 /* XXX log only in the verify_krb4_user() call */
474 log_rerror(APLOG_MARK, APLOG_ERR, 0, r, "Verifying krb4 password failed");
475 ret = (!conf->krb_authoritative && all_principals_unkown == 1 && ret == KDC_PR_UNKNOWN) ?
476 DECLINED : HTTP_UNAUTHORIZED;
480 user = ap_pstrdup(r->pool, sent_name);
482 user = ap_pstrcat(r->pool, user, ".", sent_instance, NULL);
483 user = ap_pstrcat(r->pool, user, "@", realm, NULL);
486 MK_AUTH_TYPE = "Basic";
487 ap_table_setn(r->subprocess_env, "KRBTKFILE", tkt_file_p);
489 if (!conf->krb_save_credentials)
490 krb4_cache_cleanup(tkt_file);
494 krb4_cache_cleanup(tkt_file);
503 /***************************************************************************
504 Username/Password Validation for Krb5
505 ***************************************************************************/
507 /* MIT kerberos uses replay cache checks even during credential verification
508 * (i.e. in krb5_verify_init_creds()), which is obviosuly useless. In order to
509 * avoid problems with multiple apache processes accessing the same rcache file
510 * we had to use this call instead, which is only a bit modified version of
511 * krb5_verify_init_creds() */
512 static krb5_error_code
513 verify_krb5_init_creds(request_rec *r, krb5_context context, krb5_creds *creds,
514 krb5_principal ap_req_server, krb5_keytab ap_req_keytab)
518 krb5_ccache local_ccache = NULL;
519 krb5_creds *new_creds = NULL;
520 krb5_auth_context auth_context = NULL;
521 krb5_keytab keytab = NULL;
524 memset(&req, 0, sizeof(req));
526 if (ap_req_keytab == NULL) {
527 ret = krb5_kt_default (context, &keytab);
531 keytab = ap_req_keytab;
533 ret = krb5_cc_resolve(context, "MEMORY:", &local_ccache);
535 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
536 "krb5_cc_resolve() failed when verifying KDC");
540 ret = krb5_cc_initialize(context, local_ccache, creds->client);
542 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
543 "krb5_cc_initialize() failed when verifying KDC");
547 ret = krb5_cc_store_cred (context, local_ccache, creds);
549 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
550 "krb5_cc_initialize() failed when verifying KDC");
554 ret = krb5_unparse_name(context, ap_req_server, &server_name);
556 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
557 "krb5_unparse_name() failed when verifying KDC");
560 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
561 "Trying to verify authenticity of KDC using principal %s", server_name);
564 if (!krb5_principal_compare (context, ap_req_server, creds->server)) {
565 krb5_creds match_cred;
567 memset (&match_cred, 0, sizeof(match_cred));
569 match_cred.client = creds->client;
570 match_cred.server = ap_req_server;
572 ret = krb5_get_credentials (context, 0, local_ccache,
573 &match_cred, &new_creds);
575 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
576 "krb5_get_credentials() failed when verifying KDC");
582 ret = krb5_mk_req_extended (context, &auth_context, 0, NULL, creds, &req);
584 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
585 "krb5_mk_req_extended() failed when verifying KDC");
589 krb5_auth_con_free (context, auth_context);
591 ret = krb5_auth_con_init(context, &auth_context);
593 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
594 "krb5_auth_con_init() failed when verifying KDC");
597 /* use KRB5_AUTH_CONTEXT_DO_SEQUENCE to skip replay cache checks */
598 krb5_auth_con_setflags(context, auth_context, KRB5_AUTH_CONTEXT_DO_SEQUENCE);
600 ret = krb5_rd_req (context, &auth_context, &req, ap_req_server,
603 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
604 "krb5_rd_req() failed when verifying KDC");
610 /* XXX Do I ever want to support Heimdal 0.4 ??? */
611 krb5_data_free(&req);
613 krb5_free_data_contents(context, &req);
616 krb5_auth_con_free (context, auth_context);
618 krb5_free_creds (context, new_creds);
619 if (ap_req_keytab == NULL && keytab)
620 krb5_kt_close (context, keytab);
622 krb5_cc_destroy (context, local_ccache);
627 /* Inspired by krb5_verify_user from Heimdal */
628 static krb5_error_code
629 verify_krb5_user(request_rec *r, krb5_context context, krb5_principal principal,
630 const char *password, const char *service, krb5_keytab keytab,
631 int krb_verify_kdc, krb5_ccache *ccache)
634 krb5_principal server = NULL;
636 krb5_ccache ret_ccache = NULL;
639 /* XXX error messages shouldn't be logged here (and in the while() loop in
640 * authenticate_user_krb5pwd() as weell), in order to avoid confusing log
641 * entries when using multiple realms */
643 memset(&creds, 0, sizeof(creds));
645 ret = krb5_unparse_name(context, principal, &name);
647 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
648 "Trying to get TGT for user %s", name);
652 ret = krb5_get_init_creds_password(context, &creds, principal,
653 (char *)password, NULL,
654 NULL, 0, NULL, NULL);
656 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
657 "krb5_get_init_creds_password() failed: %s",
658 krb5_get_err_text(context, ret));
662 ret = krb5_sname_to_principal(context, ap_get_server_name(r), service,
663 KRB5_NT_SRV_HST, &server);
665 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
666 "krb5_sname_to_principal() failed: %s",
667 krb5_get_err_text(context, ret));
670 /* XXX log_debug: lookig for <server_princ> in keytab */
676 krb5_get_default_realm(context, &realm);
677 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
678 "trying to verify password using key for %s/%s@%s",
679 service, ap_get_server_name(r), realm);
683 if (krb_verify_kdc &&
684 (ret = verify_krb5_init_creds(r, context, &creds, server, keytab))) {
685 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
686 "failed to verify krb5 credentials: %s",
687 krb5_get_err_text(context, ret));
691 ret = krb5_cc_resolve(context, "MEMORY:", &ret_ccache);
693 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
694 "generating new memory ccache failed: %s",
695 krb5_get_err_text(context, ret));
699 ret = krb5_cc_initialize(context, ret_ccache, principal);
701 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
702 "krb5_cc_initialize() failed: %s",
703 krb5_get_err_text(context, ret));
707 ret = krb5_cc_store_cred(context, ret_ccache, &creds);
709 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
710 "krb5_cc_store_cred() failed: %s",
711 krb5_get_err_text(context, ret));
714 *ccache = ret_ccache;
718 krb5_free_cred_contents(context, &creds);
720 krb5_free_principal(context, server);
722 krb5_cc_destroy(context, ret_ccache);
728 krb5_cache_cleanup(void *data)
730 krb5_context context;
732 krb5_error_code problem;
733 char *cache_name = (char *) data;
735 problem = krb5_init_context(&context);
737 /* ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL, "krb5_init_context() failed"); */
738 return HTTP_INTERNAL_SERVER_ERROR;
741 problem = krb5_cc_resolve(context, cache_name, &cache);
743 /* log_error(APLOG_MARK, APLOG_ERR, 0, NULL,
744 "krb5_cc_resolve() failed (%s: %s)",
745 cache_name, krb5_get_err_text(context, problem)); */
746 return HTTP_INTERNAL_SERVER_ERROR;
749 krb5_cc_destroy(context, cache);
750 krb5_free_context(context);
755 create_krb5_ccache(krb5_context kcontext,
757 kerb_auth_config *conf,
758 krb5_principal princ,
763 krb5_error_code problem;
765 krb5_ccache tmp_ccache = NULL;
767 ccname = ap_psprintf(r->pool, "FILE:%s/krb5cc_apache_XXXXXX", P_tmpdir);
768 fd = mkstemp(ccname + strlen("FILE:"));
770 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
771 "mkstemp() failed: %s", strerror(errno));
772 ret = HTTP_INTERNAL_SERVER_ERROR;
777 problem = krb5_cc_resolve(kcontext, ccname, &tmp_ccache);
779 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
780 "krb5_cc_resolve() failed: %s",
781 krb5_get_err_text(kcontext, problem));
782 ret = HTTP_INTERNAL_SERVER_ERROR;
787 problem = krb5_cc_initialize(kcontext, tmp_ccache, princ);
789 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
790 "Cannot initialize krb5 ccache %s: krb5_cc_initialize() failed: %s",
791 ccname, krb5_get_err_text(kcontext, problem));
792 ret = HTTP_INTERNAL_SERVER_ERROR;
796 ap_table_setn(r->subprocess_env, "KRB5CCNAME", ccname);
797 ap_register_cleanup(r->pool, ccname,
798 krb5_cache_cleanup, ap_null_cleanup);
800 *ccache = tmp_ccache;
807 krb5_cc_destroy(kcontext, tmp_ccache);
813 store_krb5_creds(krb5_context kcontext,
815 kerb_auth_config *conf,
816 krb5_ccache delegated_cred)
819 krb5_error_code problem;
820 krb5_principal princ;
824 problem = krb5_cc_get_principal(kcontext, delegated_cred, &princ);
826 snprintf(errstr, sizeof(errstr), "krb5_cc_get_principal() failed: %s",
827 krb5_get_err_text(kcontext, problem));
828 return HTTP_INTERNAL_SERVER_ERROR;
831 ret = create_krb5_ccache(kcontext, r, conf, princ, &ccache);
833 krb5_free_principal(kcontext, princ);
838 problem = krb5_cc_copy_cache(kcontext, delegated_cred, ccache);
840 problem = krb5_cc_copy_creds(kcontext, delegated_cred, ccache);
842 krb5_free_principal(kcontext, princ);
844 snprintf(errstr, sizeof(errstr), "Failed to store credentials: %s",
845 krb5_get_err_text(kcontext, problem));
846 krb5_cc_destroy(kcontext, ccache);
847 return HTTP_INTERNAL_SERVER_ERROR;
850 krb5_cc_close(kcontext, ccache);
855 int authenticate_user_krb5pwd(request_rec *r,
856 kerb_auth_config *conf,
857 const char *auth_line)
859 const char *sent_pw = NULL;
860 const char *sent_name = NULL;
861 const char *realms = NULL;
862 const char *realm = NULL;
863 krb5_context kcontext = NULL;
864 krb5_error_code code;
865 krb5_principal client = NULL;
866 krb5_ccache ccache = NULL;
867 krb5_keytab keytab = NULL;
870 int all_principals_unkown;
872 code = krb5_init_context(&kcontext);
874 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
875 "Cannot initialize Kerberos5 context (%d)", code);
876 return HTTP_INTERNAL_SERVER_ERROR;
879 sent_pw = ap_pbase64decode(r->pool, auth_line);
880 sent_name = ap_getword (r->pool, &sent_pw, ':');
881 /* do not allow user to override realm setting of server */
882 if (strchr(sent_name, '@')) {
883 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
884 "specifying realm in user name is prohibited");
885 ret = HTTP_UNAUTHORIZED;
889 if (sent_pw == NULL || *sent_pw == '\0') {
890 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
891 "empty passwords are not accepted");
892 ret = HTTP_UNAUTHORIZED;
896 if (conf->krb_5_keytab)
897 krb5_kt_resolve(kcontext, conf->krb_5_keytab, &keytab);
899 all_principals_unkown = 1;
900 realms = conf->krb_auth_realms;
903 if (realms && (realm = ap_getword_white(r->pool, &realms)))
904 name = ap_psprintf(r->pool, "%s@%s", sent_name, realm);
907 krb5_free_principal(kcontext, client);
911 code = krb5_parse_name(kcontext, name, &client);
913 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
914 "krb5_parse_name() failed: %s",
915 krb5_get_err_text(kcontext, code));
919 code = verify_krb5_user(r, kcontext, client, sent_pw,
920 conf->krb_service_name,
921 keytab, conf->krb_verify_kdc, &ccache);
922 if (!conf->krb_authoritative && code) {
923 /* if we're not authoritative, we allow authentication to pass on
924 * to another modules if (and only if) the user is not known to us */
925 if (all_principals_unkown && code != KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN)
926 all_principals_unkown = 0;
932 /* ap_getword_white() used above shifts the parameter, so it's not
933 needed to touch the realms variable */
934 } while (realms && *realms);
936 memset((char *)sent_pw, 0, strlen(sent_pw));
939 if (!conf->krb_authoritative && all_principals_unkown == 1 && code == KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN)
942 ret = HTTP_UNAUTHORIZED;
947 code = krb5_unparse_name(kcontext, client, &name);
949 log_rerror(APLOG_MARK, APLOG_ERR, 0, r, "krb5_unparse_name() failed: %s",
950 krb5_get_err_text(kcontext, code));
951 ret = HTTP_UNAUTHORIZED;
954 MK_USER = ap_pstrdup (r->pool, name);
955 MK_AUTH_TYPE = "Basic";
958 if (conf->krb_save_credentials)
959 store_krb5_creds(kcontext, r, conf, ccache);
964 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
965 "kerb_authenticate_user_krb5pwd ret=%d user=%s authtype=%s",
966 ret, (MK_USER)?MK_USER:"(NULL)", (MK_AUTH_TYPE)?MK_AUTH_TYPE:"(NULL)");
968 krb5_free_principal(kcontext, client);
970 krb5_cc_destroy(kcontext, ccache);
972 krb5_kt_close(kcontext, keytab);
973 krb5_free_context(kcontext);
978 /*********************************************************************
979 * GSSAPI Authentication
980 ********************************************************************/
983 get_gss_error(MK_POOL *p, OM_uint32 err_maj, OM_uint32 err_min, char *prefix)
985 OM_uint32 maj_stat, min_stat;
986 OM_uint32 msg_ctx = 0;
987 gss_buffer_desc status_string;
990 err_msg = ap_pstrdup(p, prefix);
992 maj_stat = gss_display_status (&min_stat,
998 if (GSS_ERROR(maj_stat))
1000 err_msg = ap_pstrcat(p, err_msg, ": ", (char*) status_string.value, NULL);
1001 gss_release_buffer(&min_stat, &status_string);
1003 maj_stat = gss_display_status (&min_stat,
1009 if (!GSS_ERROR(maj_stat)) {
1010 err_msg = ap_pstrcat(p, err_msg,
1011 " (", (char*) status_string.value, ")", NULL);
1012 gss_release_buffer(&min_stat, &status_string);
1014 } while (!GSS_ERROR(maj_stat) && msg_ctx != 0);
1020 store_gss_creds(request_rec *r, kerb_auth_config *conf, char *princ_name,
1021 gss_cred_id_t delegated_cred)
1023 OM_uint32 maj_stat, min_stat;
1024 krb5_principal princ = NULL;
1025 krb5_ccache ccache = NULL;
1026 krb5_error_code problem;
1027 krb5_context context;
1028 int ret = HTTP_INTERNAL_SERVER_ERROR;
1030 problem = krb5_init_context(&context);
1032 log_rerror(APLOG_MARK, APLOG_ERR, 0, r, "Cannot initialize krb5 context");
1033 return HTTP_INTERNAL_SERVER_ERROR;
1036 problem = krb5_parse_name(context, princ_name, &princ);
1038 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1039 "Cannot parse delegated username (%s)", krb5_get_err_text(context, problem));
1043 problem = create_krb5_ccache(context, r, conf, princ, &ccache);
1045 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1046 "Cannot create krb5 ccache (%s)", krb5_get_err_text(context, problem));
1050 maj_stat = gss_krb5_copy_ccache(&min_stat, delegated_cred, ccache);
1051 if (GSS_ERROR(maj_stat)) {
1052 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1053 "Cannot store delegated credential (%s)",
1054 get_gss_error(r->pool, maj_stat, min_stat, "gss_krb5_copy_ccache"));
1058 krb5_cc_close(context, ccache);
1064 krb5_free_principal(context, princ);
1066 krb5_cc_destroy(context, ccache);
1067 krb5_free_context(context);
1072 get_gss_creds(request_rec *r,
1073 kerb_auth_config *conf,
1074 gss_cred_id_t *server_creds)
1076 gss_buffer_desc token = GSS_C_EMPTY_BUFFER;
1077 OM_uint32 major_status, minor_status, minor_status2;
1078 gss_name_t server_name = GSS_C_NO_NAME;
1081 snprintf(buf, sizeof(buf), "%s@%s", conf->krb_service_name,
1082 ap_get_server_name(r));
1085 token.length = strlen(buf) + 1;
1087 major_status = gss_import_name(&minor_status, &token,
1088 GSS_C_NT_HOSTBASED_SERVICE,
1090 memset(&token, 0, sizeof(token));
1091 if (GSS_ERROR(major_status)) {
1092 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1093 "%s", get_gss_error(r->pool, major_status, minor_status,
1094 "gss_import_name() failed"));
1095 return HTTP_INTERNAL_SERVER_ERROR;
1098 major_status = gss_display_name(&minor_status, server_name, &token, NULL);
1099 if (GSS_ERROR(major_status)) {
1100 /* Perhaps we could just ignore this error but it's safer to give up now,
1102 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1103 "%s", get_gss_error(r->pool, major_status, minor_status,
1104 "gss_display_name() failed"));
1105 return HTTP_INTERNAL_SERVER_ERROR;
1108 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, "Acquiring creds for %s",
1110 gss_release_buffer(&minor_status, &token);
1112 major_status = gss_acquire_cred(&minor_status, server_name, GSS_C_INDEFINITE,
1113 GSS_C_NO_OID_SET, GSS_C_ACCEPT,
1114 server_creds, NULL, NULL);
1115 gss_release_name(&minor_status2, &server_name);
1116 if (GSS_ERROR(major_status)) {
1117 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1118 "%s", get_gss_error(r->pool, major_status, minor_status,
1119 "gss_acquire_cred() failed"));
1120 return HTTP_INTERNAL_SERVER_ERROR;
1125 * With MIT Kerberos 5 1.3.x the gss_cred_id_t is the same as
1126 * krb5_gss_cred_id_t and krb5_gss_cred_id_rec contains a pointer to
1128 * This allows us to override the replay cache function vector with
1130 * Note that this is a dirty hack to get things working and there may
1131 * well be unknown side-effects.
1134 krb5_gss_cred_id_t gss_creds = (krb5_gss_cred_id_t) *server_creds;
1136 if (gss_creds && gss_creds->rcache && gss_creds->rcache->ops &&
1137 gss_creds->rcache->ops->type &&
1138 memcmp(gss_creds->rcache->ops->type, "dfl", 3) == 0)
1139 /* Override the rcache operations */
1140 gss_creds->rcache->ops = &mod_auth_kerb_rc_ops;
1148 cmp_gss_type(gss_buffer_t token, gss_OID oid)
1153 if (token->length == 0)
1154 return GSS_S_DEFECTIVE_TOKEN;
1158 return GSS_S_DEFECTIVE_TOKEN;
1161 if ((len & 0x7f) > 4)
1162 return GSS_S_DEFECTIVE_TOKEN;
1166 return GSS_S_DEFECTIVE_TOKEN;
1168 if (((OM_uint32) *p++) != oid->length)
1169 return GSS_S_DEFECTIVE_TOKEN;
1171 return memcmp(p, oid->elements, oid->length);
1175 authenticate_user_gss(request_rec *r, kerb_auth_config *conf,
1176 const char *auth_line, char **negotiate_ret_value)
1178 OM_uint32 major_status, minor_status, minor_status2;
1179 gss_buffer_desc input_token = GSS_C_EMPTY_BUFFER;
1180 gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER;
1181 const char *auth_param = NULL;
1183 gss_name_t client_name = GSS_C_NO_NAME;
1184 gss_cred_id_t delegated_cred = GSS_C_NO_CREDENTIAL;
1186 (*accept_sec_token)(OM_uint32 *, gss_ctx_id_t *, const gss_cred_id_t,
1187 const gss_buffer_t, const gss_channel_bindings_t,
1188 gss_name_t *, gss_OID *, gss_buffer_t, OM_uint32 *,
1189 OM_uint32 *, gss_cred_id_t *);
1190 gss_OID_desc spnego_oid;
1191 gss_ctx_id_t context = GSS_C_NO_CONTEXT;
1192 gss_cred_id_t server_creds = GSS_C_NO_CREDENTIAL;
1194 *negotiate_ret_value = "\0";
1196 spnego_oid.length = 6;
1197 spnego_oid.elements = (void *)"\x2b\x06\x01\x05\x05\x02";
1199 if (conf->krb_5_keytab) {
1201 /* we don't use the ap_* calls here, since the string passed to putenv()
1202 * will become part of the enviroment and shouldn't be free()ed by apache
1204 ktname = malloc(strlen("KRB5_KTNAME=") + strlen(conf->krb_5_keytab) + 1);
1205 if (ktname == NULL) {
1206 log_rerror(APLOG_MARK, APLOG_ERR, 0, r, "malloc() failed: not enough memory");
1207 ret = HTTP_INTERNAL_SERVER_ERROR;
1210 sprintf(ktname, "KRB5_KTNAME=%s", conf->krb_5_keytab);
1213 /* Seems to be also supported by latest MIT */
1214 gsskrb5_register_acceptor_identity(conf->krb_5_keytab);
1218 ret = get_gss_creds(r, conf, &server_creds);
1222 /* ap_getword() shifts parameter */
1223 auth_param = ap_getword_white(r->pool, &auth_line);
1224 if (auth_param == NULL) {
1225 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1226 "No Authorization parameter in request from client");
1227 ret = HTTP_UNAUTHORIZED;
1231 input_token.length = ap_base64decode_len(auth_param) + 1;
1232 input_token.value = ap_pcalloc(r->connection->pool, input_token.length);
1233 if (input_token.value == NULL) {
1234 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1235 "ap_pcalloc() failed (not enough memory)");
1236 ret = HTTP_INTERNAL_SERVER_ERROR;
1239 input_token.length = ap_base64decode(input_token.value, auth_param);
1241 accept_sec_token = (cmp_gss_type(&input_token, &spnego_oid) == 0) ?
1242 gss_accept_sec_context_spnego : gss_accept_sec_context;
1244 /* pridat: Read client Negotiate data of length XXX, prefix YYY */
1245 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, "Verifying client data using %s",
1246 (accept_sec_token == gss_accept_sec_context)
1248 : "SPNEGO GSS-API");
1250 major_status = accept_sec_token(&minor_status,
1254 GSS_C_NO_CHANNEL_BINDINGS,
1261 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
1262 "Verification returned code %d", major_status);
1263 if (output_token.length) {
1267 len = ap_base64encode_len(output_token.length) + 1;
1268 token = ap_pcalloc(r->connection->pool, len + 1);
1269 if (token == NULL) {
1270 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1271 "ap_pcalloc() failed (not enough memory)");
1272 ret = HTTP_INTERNAL_SERVER_ERROR;
1273 gss_release_buffer(&minor_status2, &output_token);
1276 ap_base64encode(token, output_token.value, output_token.length);
1278 *negotiate_ret_value = token;
1279 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
1280 "GSS-API token of length %d bytes will be sent back",
1281 output_token.length);
1282 gss_release_buffer(&minor_status2, &output_token);
1285 if (GSS_ERROR(major_status)) {
1286 if (input_token.length > 7 && memcmp(input_token.value, "NTLMSSP", 7) == 0)
1287 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
1288 "Warning: received token seems to be NTLM, which isn't supported by the Kerberos module. Check your IE configuration.");
1290 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1291 "%s", get_gss_error(r->pool, major_status, minor_status,
1292 "gss_accept_sec_context() failed"));
1293 /* Don't offer the Negotiate method again if call to GSS layer failed */
1294 *negotiate_ret_value = NULL;
1295 ret = HTTP_UNAUTHORIZED;
1300 /* This is a _Kerberos_ module so multiple authentication rounds aren't
1301 * supported. If we wanted a generic GSS authentication we would have to do
1302 * some magic with exporting context etc. */
1303 if (major_status & GSS_S_CONTINUE_NEEDED) {
1304 ret = HTTP_UNAUTHORIZED;
1309 major_status = gss_display_name(&minor_status, client_name, &output_token, NULL);
1310 gss_release_name(&minor_status, &client_name);
1311 if (GSS_ERROR(major_status)) {
1312 log_rerror(APLOG_MARK, APLOG_ERR, 0, r,
1313 "%s", get_gss_error(r->pool, major_status, minor_status,
1314 "gss_export_name() failed"));
1315 ret = HTTP_INTERNAL_SERVER_ERROR;
1319 MK_AUTH_TYPE = MECH_NEGOTIATE;
1320 MK_USER = ap_pstrdup(r->pool, output_token.value);
1322 if (conf->krb_save_credentials && delegated_cred != GSS_C_NO_CREDENTIAL)
1323 store_gss_creds(r, conf, (char *)output_token.value, delegated_cred);
1325 if (*negotiate_ret_value)
1326 set_kerb_auth_headers(r, conf, 0, 0, *negotiate_ret_value);
1328 gss_release_buffer(&minor_status, &output_token);
1334 gss_release_cred(&minor_status, &delegated_cred);
1336 if (output_token.length)
1337 gss_release_buffer(&minor_status, &output_token);
1339 if (client_name != GSS_C_NO_NAME)
1340 gss_release_name(&minor_status, &client_name);
1342 if (server_creds != GSS_C_NO_CREDENTIAL)
1343 gss_release_cred(&minor_status, &server_creds);
1345 if (context != GSS_C_NO_CONTEXT)
1346 gss_delete_sec_context(&minor_status, &context, GSS_C_NO_BUFFER);
1353 already_succeeded(request_rec *r)
1355 if (ap_is_initial_req(r) || MK_AUTH_TYPE == NULL)
1357 if (strcmp(MK_AUTH_TYPE, MECH_NEGOTIATE) ||
1358 (strcmp(MK_AUTH_TYPE, "Basic") && strchr(MK_USER, '@')))
1364 set_kerb_auth_headers(request_rec *r, const kerb_auth_config *conf,
1365 int use_krb4, int use_krb5pwd, char *negotiate_ret_value)
1367 const char *auth_name = NULL;
1369 char *negoauth_param;
1370 const char *header_name =
1371 (r->proxyreq == PROXYREQ_PROXY) ? "Proxy-Authenticate" : "WWW-Authenticate";
1373 /* get the user realm specified in .htaccess */
1374 auth_name = ap_auth_name(r);
1376 /* XXX should the WWW-Authenticate header be cleared first?
1377 * apache in the proxy mode should retain client's authN headers? */
1379 if (negotiate_ret_value != NULL && conf->krb_method_gssapi) {
1380 negoauth_param = (*negotiate_ret_value == '\0') ? MECH_NEGOTIATE :
1381 ap_pstrcat(r->pool, MECH_NEGOTIATE " ", negotiate_ret_value, NULL);
1382 ap_table_add(r->err_headers_out, header_name, negoauth_param);
1384 if ((use_krb5pwd && conf->krb_method_k5pass) || conf->krb_delegate_basic) {
1385 ap_table_add(r->err_headers_out, header_name,
1386 ap_pstrcat(r->pool, "Basic realm=\"", auth_name, "\"", NULL));
1393 ((use_krb4 && conf->krb_method_k4pass) || conf->krb_delegate_basic))
1394 ap_table_add(r->err_headers_out, header_name,
1395 ap_pstrcat(r->pool, "Basic realm=\"", auth_name, "\"", NULL));
1399 int kerb_authenticate_user(request_rec *r)
1401 kerb_auth_config *conf =
1402 (kerb_auth_config *) ap_get_module_config(r->per_dir_config,
1404 const char *auth_type = NULL;
1405 const char *auth_line = NULL;
1406 const char *type = NULL;
1407 int use_krb5 = 0, use_krb4 = 0;
1409 static int last_return = HTTP_UNAUTHORIZED;
1410 char *negotiate_ret_value = NULL;
1412 /* get the type specified in .htaccess */
1413 type = ap_auth_type(r);
1415 log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
1416 "kerb_authenticate_user entered with user %s and auth_type %s",
1417 (MK_USER)?MK_USER:"(NULL)",type?type:"(NULL)");
1419 if (type && strcasecmp(type, "Kerberos") == 0)
1420 use_krb5 = use_krb4 = 1;
1421 else if(type && strcasecmp(type, "KerberosV5") == 0)
1423 else if(type && strcasecmp(type, "KerberosV4") == 0)
1428 /* get what the user sent us in the HTTP header */
1429 auth_line = MK_TABLE_GET(r->headers_in, (r->proxyreq == PROXYREQ_PROXY)
1430 ? "Proxy-Authorization"
1433 set_kerb_auth_headers(r, conf, use_krb4, use_krb5,
1434 (use_krb5) ? "\0" : NULL);
1435 return HTTP_UNAUTHORIZED;
1437 auth_type = ap_getword_white(r->pool, &auth_line);
1439 /* If we are delegating Basic to other modules, DECLINE the request */
1440 if (conf->krb_delegate_basic &&
1442 !conf->krb_method_k5pass &&
1445 !conf->krb_method_k4pass &&
1447 (strcasecmp(auth_type, "Basic") == 0))
1450 if (already_succeeded(r))
1453 ret = HTTP_UNAUTHORIZED;
1456 if (use_krb5 && conf->krb_method_gssapi &&
1457 strcasecmp(auth_type, MECH_NEGOTIATE) == 0) {
1458 ret = authenticate_user_gss(r, conf, auth_line, &negotiate_ret_value);
1459 } else if (use_krb5 && conf->krb_method_k5pass &&
1460 strcasecmp(auth_type, "Basic") == 0) {
1461 ret = authenticate_user_krb5pwd(r, conf, auth_line);
1466 if (ret == HTTP_UNAUTHORIZED && use_krb4 && conf->krb_method_k4pass &&
1467 strcasecmp(auth_type, "Basic") == 0)
1468 ret = authenticate_user_krb4pwd(r, conf, auth_line);
1471 if (ret == HTTP_UNAUTHORIZED)
1472 set_kerb_auth_headers(r, conf, use_krb4, use_krb5, negotiate_ret_value);
1474 /* XXX log_debug: if ret==OK, log(user XY authenticated) */
1481 /***************************************************************************
1482 Module Setup/Configuration
1483 ***************************************************************************/
1484 #ifndef STANDARD20_MODULE_STUFF
1485 module MODULE_VAR_EXPORT auth_kerb_module = {
1486 STANDARD_MODULE_STUFF,
1487 NULL, /* module initializer */
1488 kerb_dir_create_config, /* per-directory config creator */
1489 NULL, /* per-directory config merger */
1490 NULL, /* per-server config creator */
1491 NULL, /* per-server config merger */
1492 kerb_auth_cmds, /* command table */
1493 NULL, /* [ 9] content handlers */
1494 NULL, /* [ 2] URI-to-filename translation */
1495 kerb_authenticate_user, /* [ 5] check/validate user_id */
1496 NULL, /* [ 6] check user_id is valid *here* */
1497 NULL, /* [ 4] check access by host address */
1498 NULL, /* [ 7] MIME type checker/setter */
1499 NULL, /* [ 8] fixups */
1500 NULL, /* [10] logger */
1501 NULL, /* [ 3] header parser */
1502 NULL, /* process initialization */
1503 NULL, /* process exit/cleanup */
1504 NULL /* [ 1] post read_request handling */
1506 ,NULL, /* EAPI: add_module */
1507 NULL, /* EAPI: remove_module */
1508 NULL, /* EAPI: rewrite_command */
1509 NULL /* EAPI: new_connection */
1514 kerb_init_handler(apr_pool_t *p, apr_pool_t *plog,
1515 apr_pool_t *ptemp, server_rec *s)
1517 ap_add_version_component(p, "mod_auth_kerb/" MODAUTHKERB_VERSION);
1521 void kerb_register_hooks(apr_pool_t *p)
1523 ap_hook_post_config(kerb_init_handler, NULL, NULL, APR_HOOK_MIDDLE);
1524 ap_hook_check_user_id(kerb_authenticate_user, NULL, NULL, APR_HOOK_MIDDLE);
1527 module AP_MODULE_DECLARE_DATA auth_kerb_module =
1529 STANDARD20_MODULE_STUFF,
1530 kerb_dir_create_config, /* create per-dir conf structures */
1531 NULL, /* merge per-dir conf structures */
1532 NULL, /* create per-server conf structures */
1533 NULL, /* merge per-server conf structures */
1534 kerb_auth_cmds, /* table of configuration directives */
1535 kerb_register_hooks /* register hooks */