eigrpd: Make code a bit easier to read in eigrp_update.c

Lots of multiple pointer dereferences that made the
code lines really long, so let's properly setup
the pointers in a way that makes it easier to read.

No need to lookup the eigrp pointer because we already
have it, so let's use this( this will be good for the
future too when we have VRF's).

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

1 files changed, 51 insertions, 56 deletions

diff --git a/eigrpd/eigrp_update.c b/eigrpd/eigrp_update.c
index afe381459..63708b144 100644
--- a/eigrpd/eigrp_update.c
+++ b/eigrpd/eigrp_update.c
@@ -564,42 +564,43 @@ void eigrp_update_send_EOT(struct eigrp_neighbor *nbr)
 	struct prefix_list *plist;
 	struct access_list *alist_i;
 	struct prefix_list *plist_i;
-	struct eigrp *e;
+	struct eigrp_interface *ei = nbr->ei;
+	struct eigrp *eigrp = ei->eigrp;
 	struct prefix *dest_addr;
-	u_int32_t seq_no = nbr->ei->eigrp->sequence_number;
+	u_int32_t seq_no = eigrp->sequence_number;
 
-	ep = eigrp_packet_new(nbr->ei->ifp->mtu, nbr);
+	ep = eigrp_packet_new(ei->ifp->mtu, nbr);
 
 	/* Prepare EIGRP EOT UPDATE header */
-	eigrp_packet_header_init(EIGRP_OPC_UPDATE, nbr->ei->eigrp,
+	eigrp_packet_header_init(EIGRP_OPC_UPDATE, eigrp,
 				 ep->s, EIGRP_EOT_FLAG,
 				 seq_no, nbr->recv_sequence_number);
 
 	// encode Authentication TLV, if needed
-	if((IF_DEF_PARAMS (nbr->ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5) &&
-	   (IF_DEF_PARAMS (nbr->ei->ifp)->auth_keychain != NULL)) {
-		length += eigrp_add_authTLV_MD5_to_stream(ep->s,nbr->ei);
+	if((IF_DEF_PARAMS (ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5) &&
+	   (IF_DEF_PARAMS (ei->ifp)->auth_keychain != NULL)) {
+		length += eigrp_add_authTLV_MD5_to_stream(ep->s,ei);
 	}
 
-	for (ALL_LIST_ELEMENTS(nbr->ei->eigrp->topology_table, node, nnode, pe)) {
+	for (ALL_LIST_ELEMENTS(eigrp->topology_table, node, nnode, pe)) {
 		for (ALL_LIST_ELEMENTS(pe->entries, node2, nnode2, te)) {
-			if (eigrp_nbr_split_horizon_check(te, nbr->ei))
+			if (eigrp_nbr_split_horizon_check(te, ei))
 				continue;
 
-			if ((length + 0x001D) > (u_int16_t)nbr->ei->ifp->mtu) {
+			if ((length + 0x001D) > (u_int16_t)ei->ifp->mtu) {
 				eigrp_update_place_on_nbr_queue (nbr, ep, seq_no, length);
 				seq_no++;
 
 				length = EIGRP_HEADER_LEN;
-				ep = eigrp_packet_new(nbr->ei->ifp->mtu, nbr);
-				eigrp_packet_header_init(EIGRP_OPC_UPDATE, nbr->ei->eigrp,
+				ep = eigrp_packet_new(ei->ifp->mtu, nbr);
+				eigrp_packet_header_init(EIGRP_OPC_UPDATE, eigrp,
 							 ep->s, EIGRP_EOT_FLAG,
 							 seq_no, nbr->recv_sequence_number);
 
-				if((IF_DEF_PARAMS (nbr->ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5) &&
-				   (IF_DEF_PARAMS (nbr->ei->ifp)->auth_keychain != NULL))
+				if((IF_DEF_PARAMS (ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5) &&
+				   (IF_DEF_PARAMS (ei->ifp)->auth_keychain != NULL))
 				{
-					length += eigrp_add_authTLV_MD5_to_stream(ep->s,nbr->ei);
+					length += eigrp_add_authTLV_MD5_to_stream(ep->s,ei);
 				}
 			}
 			/* Get destination address from prefix */
@@ -609,13 +610,11 @@ void eigrp_update_send_EOT(struct eigrp_neighbor *nbr)
 			 * Filtering
 			 */
 			//TODO: Work in progress
-			/* get list from eigrp process */
-			e = eigrp_lookup();
 			/* Get access-lists and prefix-lists from process and interface */
-			alist = e->list[EIGRP_FILTER_OUT];
-			plist = e->prefix[EIGRP_FILTER_OUT];
-			alist_i = nbr->ei->list[EIGRP_FILTER_OUT];
-			plist_i = nbr->ei->prefix[EIGRP_FILTER_OUT];
+			alist = eigrp->list[EIGRP_FILTER_OUT];
+			plist = eigrp->prefix[EIGRP_FILTER_OUT];
+			alist_i = ei->list[EIGRP_FILTER_OUT];
+			plist_i = ei->prefix[EIGRP_FILTER_OUT];
 
 			/* Check if any list fits */
 			if ((alist
@@ -627,7 +626,6 @@ void eigrp_update_send_EOT(struct eigrp_neighbor *nbr)
 							   dest_addr) == FILTER_DENY)||
 			    (plist_i && prefix_list_apply (plist_i,
 							   dest_addr) == PREFIX_DENY)) {
-				//pe->reported_metric.delay = EIGRP_MAX_METRIC;
 				continue;
 			} else {
 				length += eigrp_add_internalTLV_to_stream(ep->s, pe);
@@ -636,7 +634,7 @@ void eigrp_update_send_EOT(struct eigrp_neighbor *nbr)
 	}
 
 	eigrp_update_place_on_nbr_queue (nbr, ep, seq_no, length);
-	nbr->ei->eigrp->sequence_number = seq_no++;
+	eigrp->sequence_number = seq_no++;
 }
 
 void eigrp_update_send(struct eigrp_interface *ei)
@@ -649,9 +647,9 @@ void eigrp_update_send(struct eigrp_interface *ei)
 	struct prefix_list *plist;
 	struct access_list *alist_i;
 	struct prefix_list *plist_i;
-	struct eigrp *e;
+	struct eigrp *eigrp = ei->eigrp;
 	struct prefix *dest_addr;
-	u_int32_t seq_no = ei->eigrp->sequence_number;
+	u_int32_t seq_no = eigrp->sequence_number;
 
 	if (ei->nbrs->count == 0)
 		return;
@@ -661,7 +659,7 @@ void eigrp_update_send(struct eigrp_interface *ei)
 	ep = eigrp_packet_new(ei->ifp->mtu, NULL);
 
 	/* Prepare EIGRP INIT UPDATE header */
-	eigrp_packet_header_init(EIGRP_OPC_UPDATE, ei->eigrp,
+	eigrp_packet_header_init(EIGRP_OPC_UPDATE, eigrp,
 				 ep->s, 0, seq_no, 0);
 
 	// encode Authentication TLV, if needed
@@ -699,7 +697,7 @@ void eigrp_update_send(struct eigrp_interface *ei)
 
 			length = EIGRP_HEADER_LEN;
 			ep = eigrp_packet_new(ei->ifp->mtu, NULL);
-			eigrp_packet_header_init(EIGRP_OPC_UPDATE, ei->eigrp,
+			eigrp_packet_header_init(EIGRP_OPC_UPDATE, eigrp,
 						 ep->s, 0, seq_no, 0);
 			if ((IF_DEF_PARAMS(ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5)
 			    && (IF_DEF_PARAMS(ei->ifp)->auth_keychain != NULL)) {
@@ -713,11 +711,10 @@ void eigrp_update_send(struct eigrp_interface *ei)
 		/*
 		 * Filtering
 		 */
-		e = eigrp_lookup();
 		/* Get access-lists and prefix-lists from process and
 		 * interface */
-		alist = e->list[EIGRP_FILTER_OUT];
-		plist = e->prefix[EIGRP_FILTER_OUT];
+		alist = eigrp->list[EIGRP_FILTER_OUT];
+		plist = eigrp->prefix[EIGRP_FILTER_OUT];
 		alist_i = ei->list[EIGRP_FILTER_OUT];
 		plist_i = ei->prefix[EIGRP_FILTER_OUT];
 
@@ -764,7 +761,7 @@ void eigrp_update_send(struct eigrp_interface *ei)
 	ep->dst.s_addr = htonl(EIGRP_MULTICAST_ADDRESS);
 
 	/*This ack number we await from neighbor*/
-	ep->sequence_number = ei->eigrp->sequence_number;
+	ep->sequence_number = eigrp->sequence_number;
 
 	if (IS_DEBUG_EIGRP_PACKET(0, RECV))
 		zlog_debug("Enqueuing Update length[%u] Seq [%u]", length,
@@ -819,7 +816,8 @@ static void eigrp_update_send_GR_part(struct eigrp_neighbor *nbr)
 	struct listnode *node, *nnode;
 	struct eigrp_prefix_entry *pe;
 	struct prefix *dest_addr;
-	struct eigrp *e;
+	struct eigrp_interface *ei = nbr->ei;
+	struct eigrp *eigrp = ei->eigrp;
 	struct access_list *alist, *alist_i;
 	struct prefix_list *plist, *plist_i;
 	struct list *prefixes;
@@ -863,33 +861,30 @@ static void eigrp_update_send_GR_part(struct eigrp_neighbor *nbr)
 		}
 	}
 
-	ep = eigrp_packet_new(nbr->ei->ifp->mtu, nbr);
+	ep = eigrp_packet_new(ei->ifp->mtu, nbr);
 
 	/* Prepare EIGRP Graceful restart UPDATE header */
-	eigrp_packet_header_init(EIGRP_OPC_UPDATE, nbr->ei->eigrp, ep->s, flags,
-				 nbr->ei->eigrp->sequence_number,
+	eigrp_packet_header_init(EIGRP_OPC_UPDATE, eigrp, ep->s, flags,
+				 eigrp->sequence_number,
 				 nbr->recv_sequence_number);
 
 	// encode Authentication TLV, if needed
-	if ((IF_DEF_PARAMS(nbr->ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5)
-	    && (IF_DEF_PARAMS(nbr->ei->ifp)->auth_keychain != NULL)) {
-		length += eigrp_add_authTLV_MD5_to_stream(ep->s, nbr->ei);
+	if ((IF_DEF_PARAMS(ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5)
+	    && (IF_DEF_PARAMS(ei->ifp)->auth_keychain != NULL)) {
+		length += eigrp_add_authTLV_MD5_to_stream(ep->s, ei);
 	}
 
-	for (ALL_LIST_ELEMENTS(nbr->ei->eigrp->topology_table, node, nnode,
-			       pe)) {
+	for (ALL_LIST_ELEMENTS(eigrp->topology_table, node, nnode, pe)) {
 		/*
 		 * Filtering
 		 */
 		dest_addr = pe->destination;
-		/* get list from eigrp process */
-		e = eigrp_lookup();
 		/* Get access-lists and prefix-lists from process and interface
 		 */
-		alist = e->list[EIGRP_FILTER_OUT];
-		plist = e->prefix[EIGRP_FILTER_OUT];
-		alist_i = nbr->ei->list[EIGRP_FILTER_OUT];
-		plist_i = nbr->ei->prefix[EIGRP_FILTER_OUT];
+		alist = eigrp->list[EIGRP_FILTER_OUT];
+		plist = eigrp->prefix[EIGRP_FILTER_OUT];
+		alist_i = ei->list[EIGRP_FILTER_OUT];
+		plist_i = ei->prefix[EIGRP_FILTER_OUT];
 
 		/* Check if any list fits */
 		if ((alist
@@ -913,10 +908,10 @@ static void eigrp_update_send_GR_part(struct eigrp_neighbor *nbr)
 			send_prefixes++;
 		}
 
-		alist = e->list[EIGRP_FILTER_IN];
-		plist = e->prefix[EIGRP_FILTER_IN];
-		alist_i = nbr->ei->list[EIGRP_FILTER_IN];
-		plist_i = nbr->ei->prefix[EIGRP_FILTER_IN];
+		alist = eigrp->list[EIGRP_FILTER_IN];
+		plist = eigrp->prefix[EIGRP_FILTER_IN];
+		alist_i = ei->list[EIGRP_FILTER_IN];
+		plist_i = ei->prefix[EIGRP_FILTER_IN];
 
 		/* Check if any list fits */
 		if ((alist
@@ -942,7 +937,7 @@ static void eigrp_update_send_GR_part(struct eigrp_neighbor *nbr)
 				eigrp_prefix_entry_lookup(pe->entries, nbr);
 
 			fsm_msg.packet_type = EIGRP_OPC_UPDATE;
-			fsm_msg.eigrp = e;
+			fsm_msg.eigrp = eigrp;
 			fsm_msg.data_type = EIGRP_INT;
 			fsm_msg.adv_router = nbr;
 			fsm_msg.metrics = pe->reported_metric;
@@ -970,19 +965,19 @@ static void eigrp_update_send_GR_part(struct eigrp_neighbor *nbr)
 	}
 
 	/* compute Auth digest */
-	if ((IF_DEF_PARAMS(nbr->ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5)
-	    && (IF_DEF_PARAMS(nbr->ei->ifp)->auth_keychain != NULL)) {
-		eigrp_make_md5_digest(nbr->ei, ep->s, EIGRP_AUTH_UPDATE_FLAG);
+	if ((IF_DEF_PARAMS(ei->ifp)->auth_type == EIGRP_AUTH_TYPE_MD5)
+	    && (IF_DEF_PARAMS(ei->ifp)->auth_keychain != NULL)) {
+		eigrp_make_md5_digest(ei, ep->s, EIGRP_AUTH_UPDATE_FLAG);
 	}
 
 	/* EIGRP Checksum */
-	eigrp_packet_checksum(nbr->ei, ep->s, length);
+	eigrp_packet_checksum(ei, ep->s, length);
 
 	ep->length = length;
 	ep->dst.s_addr = nbr->src.s_addr;
 
 	/*This ack number we await from neighbor*/
-	ep->sequence_number = nbr->ei->eigrp->sequence_number;
+	ep->sequence_number = eigrp->sequence_number;
 
 	if (IS_DEBUG_EIGRP_PACKET(0, RECV))
 		zlog_debug("Enqueuing Update Init Len [%u] Seq [%u] Dest [%s]",