Heimdal DB bridge plugin for KDC back end

Merge Luke's users/lhoward/heimmig branch to trunk.  Implements a
KDC back-end plugin which interfaces to a Heimdal HDB plugin.

ticket: 6578

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@23073 dc483132-0cff-0310-8789-dd5450dbe970

6 files changed, 121 insertions, 44 deletions

diff --git a/src/kdc/do_as_req.c b/src/kdc/do_as_req.c
index 737def8d2..1feb468be 100644
--- a/src/kdc/do_as_req.c
+++ b/src/kdc/do_as_req.c
@@ -108,7 +108,7 @@ process_as_req(krb5_kdc_req *request, krb5_data *req_pkt,
     krb5_enctype useenctype;
     krb5_data e_data;
     register int i;
-    krb5_timestamp until, rtime;
+    krb5_timestamp rtime;
     char *cname = 0, *sname = 0;
     unsigned int c_flags = 0, s_flags = 0;
     krb5_principal_data client_princ;
@@ -265,7 +265,7 @@ process_as_req(krb5_kdc_req *request, krb5_data *req_pkt,
     authtime = kdc_time; /* for audit_as_request() */
 
     if ((errcode = validate_as_request(request, client, server,
-				       kdc_time, &status))) {
+				       kdc_time, &status, &e_data))) {
 	if (!status) 
 	    status = "UNKNOWN_REASON";
 	errcode += ERROR_TABLE_BASE_krb5;
@@ -339,14 +339,14 @@ process_as_req(krb5_kdc_req *request, krb5_data *req_pkt,
 	enc_tkt_reply.times.starttime = request->from;
     } else
 	enc_tkt_reply.times.starttime = kdc_time;
-    
-    until = (request->till == 0) ? kdc_infinity : request->till;
 
-    enc_tkt_reply.times.endtime =
-	min(until,
-	    min(enc_tkt_reply.times.starttime + client.max_life,
-		min(enc_tkt_reply.times.starttime + server.max_life,
-		    enc_tkt_reply.times.starttime + max_life_for_realm)));
+    kdc_get_ticket_endtime(kdc_context,
+			   enc_tkt_reply.times.starttime,
+			   kdc_infinity,
+			   request->till,
+			   &client,
+			   &server,
+			   &enc_tkt_reply.times.endtime);
 
     if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE_OK) &&
 	!isflagset(client.attributes, KRB5_KDB_DISALLOW_RENEWABLE) &&
@@ -559,6 +559,7 @@ process_as_req(krb5_kdc_req *request, krb5_data *req_pkt,
 			      &server,
 			      &client_keyblock,
 			      &server_keyblock,
+			      &server_keyblock,
 			      req_pkt,
 			      request,
 			      NULL, /* for_user_princ */
diff --git a/src/kdc/do_tgs_req.c b/src/kdc/do_tgs_req.c
index f05d25a92..71013b584 100644
--- a/src/kdc/do_tgs_req.c
+++ b/src/kdc/do_tgs_req.c
@@ -77,7 +77,7 @@ find_alternate_tgs(krb5_kdc_req *,krb5_db_entry *,
 
 static krb5_error_code 
 prepare_error_tgs(struct kdc_request_state *, krb5_kdc_req *,krb5_ticket *,int,
-                  krb5_principal,krb5_data **,const char *);
+                  krb5_principal,krb5_data **,const char *, krb5_data *);
 
 static krb5_int32
 prep_reprocess_req(krb5_kdc_req *,krb5_principal *);
@@ -88,6 +88,7 @@ process_tgs_req(krb5_data *pkt, const krb5_fulladdr *from,
                 krb5_data **response)
 {
     krb5_keyblock * subkey = 0;
+    krb5_keyblock * tgskey = 0;
     krb5_kdc_req *request = 0;
     krb5_db_entry server;
     krb5_kdc_rep reply;
@@ -103,7 +104,7 @@ process_tgs_req(krb5_data *pkt, const krb5_fulladdr *from,
     krb5_boolean more;
     krb5_timestamp kdc_time, authtime=0;
     krb5_keyblock session_key;
-    krb5_timestamp until, rtime;
+    krb5_timestamp rtime;
     krb5_keyblock *reply_key = NULL;
     krb5_keyblock *mkey_ptr;
     krb5_key_data  *server_key;
@@ -129,9 +130,11 @@ process_tgs_req(krb5_data *pkt, const krb5_fulladdr *from,
     struct kdc_request_state *state = NULL;
     krb5_pa_data *pa_tgs_req; /*points into request*/
     krb5_data scratch;
+    krb5_data e_data; /* backend-provided error data */
 
     reply.padata = 0; /* For cleanup handler */
     reply_encpart.enc_padata = 0;
+    e_data.data = NULL;
 
     session_key.contents = NULL;
 
@@ -147,7 +150,8 @@ process_tgs_req(krb5_data *pkt, const krb5_fulladdr *from,
         return retval;
     }
     errcode = kdc_process_tgs_req(request, from, pkt, &header_ticket,
-                                  &krbtgt, &k_nprincs, &subkey, &pa_tgs_req);
+                                  &krbtgt, &k_nprincs, &tgskey,
+                                  &subkey, &pa_tgs_req);
     if (header_ticket && header_ticket->enc_part2 &&
         (errcode2 = krb5_unparse_name(kdc_context, 
                                       header_ticket->enc_part2->client,
@@ -281,7 +285,7 @@ tgt_again:
     }
     
     if ((retval = validate_tgs_request(request, server, header_ticket,
-                                       kdc_time, &status))) {
+                                       kdc_time, &status, &e_data))) {
     if (!status)
         status = "UNKNOWN_REASON";
         errcode = retval + ERROR_TABLE_BASE_krb5;
@@ -540,18 +544,22 @@ tgt_again:
     } else {
         /* not a renew request */
         enc_tkt_reply.times.starttime = kdc_time;
-        until = (request->till == 0) ? kdc_infinity : request->till;
-        enc_tkt_reply.times.endtime =
-            min(until, min(enc_tkt_reply.times.starttime + server.max_life,
-               min(enc_tkt_reply.times.starttime + max_life_for_realm,
-                   header_enc_tkt->times.endtime)));
+
+	kdc_get_ticket_endtime(kdc_context,
+			       enc_tkt_reply.times.starttime,
+			       header_enc_tkt->times.endtime,
+			       request->till,
+			       &client,
+			       &server,
+			       &enc_tkt_reply.times.endtime);
+
         if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE_OK) &&
             (enc_tkt_reply.times.endtime < request->till) &&
             isflagset(header_enc_tkt->flags, TKT_FLG_RENEWABLE)) {
             setflag(request->kdc_options, KDC_OPT_RENEWABLE);
             request->rtime =
                 min(request->till, header_enc_tkt->times.renew_till);
-        }
+	}
     }
     rtime = (request->rtime == 0) ? kdc_infinity : request->rtime;
 
@@ -716,6 +724,7 @@ tgt_again:
                               subkey != NULL ? subkey :
                               header_ticket->enc_part2->session,
                               &encrypting_key, /* U2U or server key */
+                              tgskey,
                               pkt,
                               request,
                               s4u_x509_user ?
@@ -974,7 +983,7 @@ cleanup:
             
         retval = prepare_error_tgs(state, request, header_ticket, errcode,
         nprincs ? server.princ : NULL,
-                   response, status);
+                   response, status, &e_data);
         if (got_err) {
             krb5_free_error_message (kdc_context, status);
             status = 0;
@@ -1009,10 +1018,13 @@ cleanup:
         free(s4u_name);
     if (subkey != NULL)
         krb5_free_keyblock(kdc_context, subkey);
+    if (tgskey != NULL)
+        krb5_free_keyblock(kdc_context, tgskey);
     if (reply.padata)
         krb5_free_pa_data(kdc_context, reply.padata);
     if (reply_encpart.enc_padata)
         krb5_free_pa_data(kdc_context, reply_encpart.enc_padata);
+    krb5_free_data_contents(kdc_context, &e_data);
 
     return retval;
 }
@@ -1021,7 +1033,8 @@ static krb5_error_code
 prepare_error_tgs (struct kdc_request_state *state,
 		   krb5_kdc_req *request, krb5_ticket *ticket, int error,
                    krb5_principal canon_server,
-                   krb5_data **response, const char *status)
+                   krb5_data **response, const char *status,
+		   krb5_data *e_data)
 {
     krb5_error errpkt;
     krb5_error_code retval = 0;
@@ -1047,8 +1060,7 @@ prepare_error_tgs (struct kdc_request_state *state,
         free(errpkt.text.data);
         return ENOMEM;
     }
-    errpkt.e_data.length = 0;
-    errpkt.e_data.data = NULL;
+    errpkt.e_data = *e_data;
     if (state)
 	retval = kdc_fast_handle_error(kdc_context, state, request, NULL, &errpkt);
     if (retval) {
diff --git a/src/kdc/kdc_authdata.c b/src/kdc/kdc_authdata.c
index d598894d2..4ccfcb98b 100644
--- a/src/kdc/kdc_authdata.c
+++ b/src/kdc/kdc_authdata.c
@@ -56,6 +56,7 @@ typedef krb5_error_code (*authdata_proc_2)
      krb5_db_entry *krbtgt,
      krb5_keyblock *client_key,
      krb5_keyblock *server_key,
+     krb5_keyblock *krbtgt_key,
      krb5_data *req_pkt,
      krb5_kdc_req *request,
      krb5_const_principal for_user_princ,
@@ -75,6 +76,7 @@ static krb5_error_code handle_request_authdata
      krb5_db_entry *krbtgt,
      krb5_keyblock *client_key,
      krb5_keyblock *server_key,
+     krb5_keyblock *krbtgt_key,
      krb5_data *req_pkt,
      krb5_kdc_req *request,
      krb5_const_principal for_user_princ,
@@ -90,6 +92,7 @@ static krb5_error_code handle_tgt_authdata
      krb5_db_entry *krbtgt,
      krb5_keyblock *client_key,
      krb5_keyblock *server_key,
+     krb5_keyblock *krbtgt_key,
      krb5_data *req_pkt,
      krb5_kdc_req *request,
      krb5_const_principal for_user_princ,
@@ -382,6 +385,7 @@ handle_request_authdata (krb5_context context,
 			 krb5_db_entry *krbtgt,
 			 krb5_keyblock *client_key,
 			 krb5_keyblock *server_key,
+                         krb5_keyblock *krbtgt_key,
 			 krb5_data *req_pkt,
 			 krb5_kdc_req *request,
 			 krb5_const_principal for_user_princ,
@@ -455,6 +459,7 @@ handle_tgt_authdata (krb5_context context,
 		     krb5_db_entry *krbtgt,
 		     krb5_keyblock *client_key,
 		     krb5_keyblock *server_key,
+		     krb5_keyblock *krbtgt_key,
 		     krb5_data *req_pkt,
 		     krb5_kdc_req *request,
 		     krb5_const_principal for_user_princ,
@@ -526,6 +531,7 @@ handle_tgt_authdata (krb5_context context,
 			    krbtgt,
 			    client_key,
 			    server_key, /* U2U or server key */
+			    krbtgt_key,
 			    enc_tkt_reply->times.authtime,
 			    tgs_req ? enc_tkt_request->authorization_data : NULL,
 			    enc_tkt_reply->session,
@@ -562,6 +568,7 @@ handle_authdata (krb5_context context,
 		 krb5_db_entry *krbtgt,
 		 krb5_keyblock *client_key,
 		 krb5_keyblock *server_key,
+		 krb5_keyblock *krbtgt_key,
 		 krb5_data *req_pkt,
 		 krb5_kdc_req *request,
 		 krb5_const_principal for_user_princ,
@@ -586,7 +593,7 @@ handle_authdata (krb5_context context,
 	case AUTHDATA_SYSTEM_V2:
 	    code = (*asys->handle_authdata.v2)(context, flags,
 					      client, server, krbtgt,
-					      client_key, server_key,
+					      client_key, server_key, krbtgt_key,
 					      req_pkt, request, for_user_princ,
 					      enc_tkt_request,
 					      enc_tkt_reply);
diff --git a/src/kdc/kdc_util.c b/src/kdc/kdc_util.c
index 9ad832e8a..b2d8d13bd 100644
--- a/src/kdc/kdc_util.c
+++ b/src/kdc/kdc_util.c
@@ -230,6 +230,7 @@ krb5_error_code
 kdc_process_tgs_req(krb5_kdc_req *request, const krb5_fulladdr *from,
 		    krb5_data *pkt, krb5_ticket **ticket,
 		    krb5_db_entry *krbtgt, int *nprincs,
+		    krb5_keyblock **tgskey,
 		    krb5_keyblock **subkey,
 		    krb5_pa_data **pa_tgs_req)
 {
@@ -243,10 +244,10 @@ kdc_process_tgs_req(krb5_kdc_req *request, const krb5_fulladdr *from,
     krb5_auth_context 	  auth_context = NULL;
     krb5_authenticator	* authenticator = NULL;
     krb5_checksum 	* his_cksum = NULL;
-    krb5_keyblock 	* key = NULL;
     krb5_kvno 		  kvno = 0;
 
     *nprincs = 0;
+    *tgskey = NULL;
 
     tmppa = find_pa_data(request->padata, KRB5_PADATA_AP_REQ);
     if (!tmppa)
@@ -289,13 +290,12 @@ kdc_process_tgs_req(krb5_kdc_req *request, const krb5_fulladdr *from,
 #endif
 
     if ((retval = kdc_get_server_key(apreq->ticket, 0, foreign_server,
-				     krbtgt, nprincs, &key, &kvno)))
+				     krbtgt, nprincs, tgskey, &kvno)))
 	goto cleanup_auth_context;
     /*
      * We do not use the KDB keytab because other parts of the TGS need the TGT key.
      */
-    retval = krb5_auth_con_setuseruserkey(kdc_context, auth_context, key);
-    krb5_free_keyblock(kdc_context, key);
+    retval = krb5_auth_con_setuseruserkey(kdc_context, auth_context, *tgskey);
     if (retval) 
 	goto cleanup_auth_context;
 
@@ -411,6 +411,10 @@ cleanup_auth_context:
     krb5_auth_con_free(kdc_context, auth_context);
 
 cleanup:
+    if (retval != 0) {
+	krb5_free_keyblock(kdc_context, *tgskey);
+	*tgskey = NULL;
+    }
     krb5_free_ap_req(kdc_context, apreq);
     return retval;
 }
@@ -932,7 +936,7 @@ fail:
 int
 validate_as_request(register krb5_kdc_req *request, krb5_db_entry client,
 		    krb5_db_entry server, krb5_timestamp kdc_time,
-		    const char **status)
+		    const char **status, krb5_data *e_data)
 {
     int		errcode;
     
@@ -1042,7 +1046,7 @@ validate_as_request(register krb5_kdc_req *request, krb5_db_entry client,
      * Check against local policy
      */
     errcode = against_local_policy_as(request, client, server,
-				      kdc_time, status); 
+				      kdc_time, status, e_data);
     if (errcode)
 	return errcode;
 
@@ -1225,7 +1229,7 @@ fetch_asn1_field(unsigned char *astream, unsigned int level,
 int
 validate_tgs_request(register krb5_kdc_req *request, krb5_db_entry server,
 		     krb5_ticket *ticket, krb5_timestamp kdc_time,
-		     const char **status)
+		     const char **status, krb5_data *e_data)
 {
     int		errcode;
     int		st_idx = 0;
@@ -1458,7 +1462,8 @@ validate_tgs_request(register krb5_kdc_req *request, krb5_db_entry server,
     /*
      * Check local policy
      */
-    errcode = against_local_policy_tgs(request, server, ticket, status);
+    errcode = against_local_policy_tgs(request, server, ticket,
+				       status, e_data);
     if (errcode)
 	return errcode;
     
@@ -1737,6 +1742,7 @@ sign_db_authdata (krb5_context context,
 		  krb5_db_entry *krbtgt,
 		  krb5_keyblock *client_key,
 		  krb5_keyblock *server_key,
+		  krb5_keyblock *krbtgt_key,
 		  krb5_timestamp authtime,
 		  krb5_authdata **tgs_authdata,
 		  krb5_keyblock *session_key,
@@ -1763,6 +1769,7 @@ sign_db_authdata (krb5_context context,
     req.authtime		= authtime;
     req.auth_data		= tgs_authdata;
     req.session_key		= session_key;
+    req.krbtgt_key		= krbtgt_key;
 
     req_data.data = (void *)&req;
     req_data.length = sizeof(req);
@@ -2166,9 +2173,9 @@ kdc_process_s4u2self_req(krb5_context context,
      * the TGT and that we have a global name service.
      */
     flags = 0;
-    switch (krb5_princ_type(kdc_context, request->server)) {
+    switch (krb5_princ_type(context, request->server)) {
     case KRB5_NT_SRV_HST:		    /* (1) */
-	if (krb5_princ_size(kdc_context, request->server) == 2)
+	if (krb5_princ_size(context, request->server) == 2)
 	    flags |= KRB5_PRINCIPAL_COMPARE_IGNORE_REALM;
 	break;
     case KRB5_NT_ENTERPRISE_PRINCIPAL:	    /* (2) */
@@ -2204,9 +2211,11 @@ kdc_process_s4u2self_req(krb5_context context,
      */
     if (is_local_principal((*s4u_x509_user)->user_id.user)) {
 	krb5_db_entry no_server;
+	krb5_data e_data;
 
+	e_data.data = NULL;
 	*nprincs = 1;
-	code = krb5_db_get_principal_ext(kdc_context,
+	code = krb5_db_get_principal_ext(context,
 					 (*s4u_x509_user)->user_id.user,
 					 KRB5_KDB_FLAG_INCLUDE_PAC,
 					 princ, nprincs, &more);
@@ -2227,8 +2236,9 @@ kdc_process_s4u2self_req(krb5_context context,
 	memset(&no_server, 0, sizeof(no_server));
 
 	code = validate_as_request(request, *princ,
-				   no_server, kdc_time, status);
+				   no_server, kdc_time, status, &e_data);
 	if (code) {
+	    krb5_free_data_contents(context, &e_data);
 	    return code;
 	}
     }
@@ -2613,3 +2623,36 @@ add_pa_data_element(krb5_context context,
     return 0;
 }
 
+void
+kdc_get_ticket_endtime(krb5_context context,
+		       krb5_timestamp starttime,
+		       krb5_timestamp endtime,
+		       krb5_timestamp till,
+		       krb5_db_entry *client,
+		       krb5_db_entry *server,
+		       krb5_timestamp *out_endtime)
+{
+    krb5_timestamp until, life;
+
+    if (till == 0)
+	till = kdc_infinity;
+
+    until = min(till, endtime);
+
+    /* check for underflow */
+    life = (until < starttime) ? 0 : until - starttime;
+
+    if (client->max_life != 0)
+	life = min(life, client->max_life);
+    if (server->max_life != 0)
+	life = min(life, server->max_life);
+    if (max_life_for_realm != 0)
+	life = min(life, max_life_for_realm);
+
+    /* check for overflow */
+    if (starttime > kdc_infinity - life)
+	*out_endtime = kdc_infinity;
+    else
+	*out_endtime = starttime + life;
+}
+
diff --git a/src/kdc/kdc_util.h b/src/kdc/kdc_util.h
index 079492250..84319f7b8 100644
--- a/src/kdc/kdc_util.h
+++ b/src/kdc/kdc_util.h
@@ -66,7 +66,8 @@ krb5_error_code kdc_process_tgs_req
 	           krb5_ticket **,
 		   krb5_db_entry *krbtgt,
 		   int *nprincs,
-	           krb5_keyblock **, krb5_pa_data **pa_tgs_req);
+	           krb5_keyblock **, krb5_keyblock **,
+		   krb5_pa_data **pa_tgs_req);
 
 krb5_error_code kdc_get_server_key (krb5_ticket *, unsigned int,
 				    krb5_boolean match_enctype,
@@ -75,7 +76,7 @@ krb5_error_code kdc_get_server_key (krb5_ticket *, unsigned int,
 
 int validate_as_request (krb5_kdc_req *, krb5_db_entry, 
 					  krb5_db_entry, krb5_timestamp,
-					  const char **);
+					  const char **, krb5_data *);
 
 int validate_forwardable(krb5_kdc_req *, krb5_db_entry, 
 			 krb5_db_entry, krb5_timestamp,
@@ -83,7 +84,7 @@ int validate_forwardable(krb5_kdc_req *, krb5_db_entry,
 
 int validate_tgs_request (krb5_kdc_req *, krb5_db_entry, 
 					  krb5_ticket *, krb5_timestamp,
-					  const char **);
+					  const char **, krb5_data *);
 
 int fetch_asn1_field (unsigned char *, unsigned int, unsigned int,
 				 krb5_data *);
@@ -144,10 +145,11 @@ krb5_error_code closedown_network (void);
 /* policy.c */
 int against_local_policy_as (krb5_kdc_req *, krb5_db_entry,
 					krb5_db_entry, krb5_timestamp,
-					const char **);
+					const char **, krb5_data *);
 
 int against_local_policy_tgs (krb5_kdc_req *, krb5_db_entry,
-					krb5_ticket *, const char **);
+					krb5_ticket *, const char **,
+					krb5_data *);
 
 /* kdc_preauth.c */
 krb5_boolean enctype_requires_etype_info_2(krb5_enctype enctype);
@@ -197,6 +199,7 @@ handle_authdata (krb5_context context,
 		 krb5_db_entry *krbtgt,
 		 krb5_keyblock *client_key,
 		 krb5_keyblock *server_key,
+		 krb5_keyblock *krbtgt_key,
 		 krb5_data *req_pkt,
 		 krb5_kdc_req *request,
 		 krb5_const_principal for_user_princ,
@@ -236,6 +239,7 @@ krb5_error_code sign_db_authdata
 		krb5_db_entry *krbtgt,
 		krb5_keyblock *client_key,
 		krb5_keyblock *server_key,
+		krb5_keyblock *krbtgt_key,
 		krb5_timestamp authtime,
 		krb5_authdata **tgs_authdata,
 		krb5_keyblock *session_key,
@@ -296,7 +300,14 @@ validate_transit_path(krb5_context context,
 	krb5_const_principal client,
 		krb5_db_entry *server,
 		      krb5_db_entry *krbtgt);
-
+void
+kdc_get_ticket_endtime(krb5_context context,
+       krb5_timestamp now,
+	       krb5_timestamp endtime,
+	       krb5_timestamp till,
+	       krb5_db_entry *client,
+	       krb5_db_entry *server,
+	       krb5_timestamp *out_endtime);
 
 void
 log_as_req(const krb5_fulladdr *from,
diff --git a/src/kdc/policy.c b/src/kdc/policy.c
index 58b26f73d..d4a70feb6 100644
--- a/src/kdc/policy.c
+++ b/src/kdc/policy.c
@@ -60,7 +60,7 @@
 int
 against_local_policy_as(register krb5_kdc_req *request, krb5_db_entry client,
 			krb5_db_entry server, krb5_timestamp kdc_time,
-			const char **status)
+			const char **status, krb5_data *e_data)
 {
     krb5_error_code		code;
     kdb_check_policy_as_req	req;
@@ -98,6 +98,7 @@ against_local_policy_as(register krb5_kdc_req *request, krb5_db_entry client,
 	return 0;
 
     *status = rep.status;
+    *e_data = rep.e_data;
 
     if (code != 0) {
 	code -= ERROR_TABLE_BASE_krb5;
@@ -113,7 +114,8 @@ against_local_policy_as(register krb5_kdc_req *request, krb5_db_entry client,
  */
 krb5_error_code
 against_local_policy_tgs(register krb5_kdc_req *request, krb5_db_entry server,
-			 krb5_ticket *ticket, const char **status)
+			 krb5_ticket *ticket, const char **status,
+			 krb5_data *e_data)
 {
     krb5_error_code		code;
     kdb_check_policy_tgs_req	req;
@@ -154,6 +156,7 @@ against_local_policy_tgs(register krb5_kdc_req *request, krb5_db_entry server,
 	return 0;
 
     *status = rep.status;
+    *e_data = rep.e_data;
 
     if (code != 0) {
 	code -= ERROR_TABLE_BASE_krb5;