diff -up dhcp-4.2.0/server/dhcpv6.c.noprefixavail dhcp-4.2.0/server/dhcpv6.c

--- dhcp-4.2.0/server/dhcpv6.c.noprefixavail	2010-10-07 13:48:45.000000000 +0200

+++ dhcp-4.2.0/server/dhcpv6.c	2010-10-13 11:00:25.000000000 +0200

@@ -1134,7 +1134,7 @@ try_client_v6_prefix(struct iasubopt **p

 		return DHCP_R_INVALIDARG;

 	}

 	tmp_plen = (int) requested_pref->data[0];

-	if ((tmp_plen < 3) || (tmp_plen > 128)) {

+	if ((tmp_plen < 3) || (tmp_plen > 128) ||((int)tmp_plen != pool->units)) {

 		return ISC_R_FAILURE;

 	}

 	memcpy(&tmp_pref, requested_pref->data + 1, sizeof(tmp_pref));

@@ -1147,9 +1147,8 @@ try_client_v6_prefix(struct iasubopt **p

 		return ISC_R_FAILURE;

 	}

-	if (((int)tmp_plen != pool->units) ||

-	    !ipv6_in_pool(&tmp_pref, pool)) {

-		return ISC_R_FAILURE;

+	if (!ipv6_in_pool(&tmp_pref, pool)) {

+		return ISC_R_ADDRNOTAVAIL;

 	}

 	if (prefix6_exists(pool, &tmp_pref, tmp_plen)) {

@@ -1409,13 +1408,6 @@ lease_to_client(struct data_string *repl

 		if ((status != ISC_R_SUCCESS) &&

 		    (status != ISC_R_NORESOURCES))

 			goto exit;

-

-		/*

-		 * If any prefix cannot be given to any IA_PD, then

-		 * set the NoPrefixAvail status code.

-		 */

-		if (reply.client_resources == 0)

-			no_resources_avail = ISC_TRUE;

 	}

 	/*

@@ -1549,36 +1541,6 @@ lease_to_client(struct data_string *repl

 					       reply.opt_state, reply.packet,

 					       required_opts_NAA,

 					       NULL);

-	} else if (no_resources_avail && (reply.ia_count == 0) &&

-		   (reply.packet->dhcpv6_msg_type == DHCPV6_SOLICIT))

-	{

-		/* Set the NoPrefixAvail status code. */

-		if (!set_status_code(STATUS_NoPrefixAvail,

-				     "No prefixes available for this "

-				     "interface.", reply.opt_state)) {

-			log_error("lease_to_client: Unable to set "

-				  "NoPrefixAvail status code.");

-			goto exit;

-		}

-

-		/* Rewind the cursor to the start. */

-		reply.cursor = REPLY_OPTIONS_INDEX;

-

-		/*

-		 * Produce an advertise that includes only:

-		 *

-		 * Status code.

-		 * Server DUID.

-		 * Client DUID.

-		 */

-		reply.buf.reply.msg_type = DHCPV6_ADVERTISE;

-		reply.cursor += store_options6((char *)reply.buf.data +

-							reply.cursor,

-					       sizeof(reply.buf) -

-					       		reply.cursor,

-					       reply.opt_state, reply.packet,

-					       required_opts_NAA,

-					       NULL);

 	} else {

 		/*

 		 * Having stored the client's IA's, store any options that

@@ -2793,16 +2755,18 @@ find_client_temporaries(struct reply_sta

  */

 static isc_result_t

 reply_process_try_addr(struct reply_state *reply, struct iaddr *addr) {

-	isc_result_t status = ISC_R_NORESOURCES;

+	isc_result_t status = ISC_R_ADDRNOTAVAIL;

 	struct ipv6_pool *pool;

 	int i;

 	struct data_string data_addr;

 	if ((reply == NULL) || (reply->shared == NULL) ||

-	    (reply->shared->ipv6_pools == NULL) || (addr == NULL) ||

-	    (reply->lease != NULL))

+	    (addr == NULL) || (reply->lease != NULL))

 		return DHCP_R_INVALIDARG;

+	if (reply->shared->ipv6_pools == NULL)

+		return ISC_R_ADDRNOTAVAIL;

+

 	memset(&data_addr, 0, sizeof(data_addr));

 	data_addr.len = addr->len;

 	data_addr.data = addr->iabuf;

@@ -3314,7 +3278,9 @@ reply_process_ia_pd(struct reply_state *

 		if (status == ISC_R_CANCELED)

 			break;

-		if ((status != ISC_R_SUCCESS) && (status != ISC_R_ADDRINUSE))

+		if ((status != ISC_R_SUCCESS) &&

+		    (status != ISC_R_ADDRINUSE) &&

+		    (status != ISC_R_ADDRNOTAVAIL))

 			goto cleanup;

 	}

@@ -3594,7 +3560,8 @@ reply_process_prefix(struct reply_state 

 			/* Either error out or skip this prefix. */

 			if ((status != ISC_R_SUCCESS) && 

-			    (status != ISC_R_ADDRINUSE)) 

+			    (status != ISC_R_ADDRINUSE) &&

+			    (status != ISC_R_ADDRNOTAVAIL))

 				goto cleanup;

 			if (reply->lease == NULL) {

@@ -3773,16 +3740,18 @@ prefix_is_owned(struct reply_state *repl

 static isc_result_t

 reply_process_try_prefix(struct reply_state *reply,

 			 struct iaddrcidrnet *pref) {

-	isc_result_t status = ISC_R_NORESOURCES;

+	isc_result_t status = ISC_R_ADDRNOTAVAIL;

 	struct ipv6_pool *pool;

 	int i;

 	struct data_string data_pref;

 	if ((reply == NULL) || (reply->shared == NULL) ||

-	    (reply->shared->ipv6_pools == NULL) || (pref == NULL) ||

-	    (reply->lease != NULL))

+	    (pref == NULL) || (reply->lease != NULL))

 		return DHCP_R_INVALIDARG;

+	if (reply->shared->ipv6_pools == NULL)

+		return ISC_R_ADDRNOTAVAIL;

+

 	memset(&data_pref, 0, sizeof(data_pref));

 	data_pref.len = 17;

 	if (!buffer_allocate(&data_pref.buffer, data_pref.len, MDL)) {