Add data structures to store announcements and partly implement updates

ffd/CMakeLists.txt

@@ -1,6 +1,7 @@
 include_directories(${CMAKE_CURRENT_SOURCE_DIR} ${FFD_BINARY_DIR} ${CMAKE_CURRENT_BINARY_DIR})
 
 add_executable(ffd
+  announce.c
   ffd.c
   neigh.c
   netif.c

ffd/announce.c

@@ -0,0 +1,83 @@
+/*
+  Copyright (c) 2012, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include "ffd.h"
+
+
+static bool is_feasable(const ffd_announce_t *announce, const ffd_nexthop_t *nexthop) {
+	if (FFD_IS_INFINITY(announce->feasability_distance))
+		return true;
+
+	int16_t seqno_diff = nexthop->metric_seqno.seqno - announce->feasability_distance.seqno;
+
+	if (seqno_diff < 0)
+		return true;
+	if (seqno_diff == 0 && nexthop->metric_seqno.metric < announce->feasability_distance.metric)
+		return true;
+
+	return false;
+}
+
+static ffd_nexthop_t* select_nexthop(const ffd_announce_t *announce) {
+	ffd_nexthop_t *ret = NULL;
+
+	ffd_nexthop_t *nexthop;
+	for (nexthop = announce->nexthop_list->next; nexthop; nexthop = nexthop->next) {
+		if (is_feasable(announce, nexthop))
+			continue;
+
+		int16_t seqno_diff = nexthop->metric_seqno.seqno - ret->metric_seqno.seqno;
+
+		if (nexthop->metric_seqno.metric < ret->metric_seqno.metric
+		    || (nexthop->metric_seqno.metric == ret->metric_seqno.metric && seqno_diff < 0)) {
+			ret = nexthop;
+		}
+	}
+
+	return ret;
+}
+
+ffd_metric_seqno_t ffd_announce_get_metric(const ffd_announce_t *announce) {
+	ffd_nexthop_t *nexthop = select_nexthop(announce);
+
+	if (nexthop)
+		return nexthop->metric_seqno;
+	else
+		return (ffd_metric_seqno_t){0xffff, 0};
+}
+
+
+ffd_announce_t* ffd_announce_new(size_t len) {
+	ffd_announce_t *a = calloc(1, sizeof(ffd_announce_t)+len);
+
+	a->len = len;
+	a->feasability_distance = (ffd_metric_seqno_t){0xffff, 0};
+
+	a->next = announce_list;
+	announce_list = a;
+
+	return a;
+}

ffd/ffd.c

@@ -51,14 +51,11 @@ static char *mesh = "bat0";
 int sockfd;
 struct timespec now;
 
+ffd_node_id_t self;
+
 ffd_iface_t *iface_list = NULL;
 
-static ffd_neigh_t self;
-//static ffd_orig_t own_data;
-
-/* neighs and origs that have been changed must be moved to front */
-//static ffd_neigh_t *neigh_data = NULL;
-//static ffd_orig_t *orig_data = NULL;
+ffd_announce_t *announce_list = NULL;
 
 
 static inline bool use_netif(const char *ifname) {
@@ -87,13 +84,27 @@ static bool init_self() {
 	if (is_eth_addr_unspec(&primary_addr))
 		return false;
 
-	memset(&self, 0, sizeof(self));
-	//memset(&own_data, 0, sizeof(own_data));
+	self.id[0] = primary_addr.d[0]^0x02;
+	self.id[1] = primary_addr.d[1];
+	self.id[2] = primary_addr.d[2];
+	self.id[3] = 0xff;
+	self.id[4] = 0xfe;
+	self.id[5] = primary_addr.d[3];
+	self.id[6] = primary_addr.d[4];
+	self.id[7] = primary_addr.d[5];
 
-	//self.addr = own_data.addr = primary_addr;
+	ffd_announce_t *announce = announce_list = calloc(1, sizeof(ffd_announce_t));
 
-	//random_bytes(&self.rev, sizeof(self.rev));
-	//random_bytes(&own_data.rev, sizeof(own_data.rev));
+	announce->node = self;
+	announce->type = 1;
+	announce->key = 1337;
+	announce->interval = 6000;
+
+	ffd_nexthop_t *nexthop = announce->nexthop_list = malloc(sizeof(ffd_nexthop_t));
+
+	nexthop->addr = ETH_ADDR_UNSPEC;
+	nexthop->metric_seqno.metric = 0;
+	nexthop->metric_seqno.seqno = 0;
 
 	return true;
 }
@@ -246,6 +257,21 @@ static void handle_tlv_ihu(const ffd_tlv_ihu_t *tlv_ihu, size_t len, const eth_a
 	fprintf(stderr, "debug: accepted IHU, txcost is %u, cost is %u now.\n", neigh->txcost, ffd_neigh_get_cost(neigh));
 }
 
+static void handle_tlv_announce_req(const ffd_tlv_announce_req_t *tlv_req, size_t len, const eth_addr_t *addr, ffd_iface_t *iface) {
+	if (len < sizeof(ffd_tlv_announce_req_t)) {
+		fprintf(stderr, "warn: received short announce request TLV.\n");
+		return;
+	}
+
+	ffd_announce_t *announce = NULL;
+
+	if (!ffd_is_node_id_unspec(&tlv_req->node)) {
+		announce = NULL;
+	}
+
+	ffd_send_update(iface, ffd_neigh_get(iface, addr), announce);
+}
+
 static void handle_tlv(ffd_tlv_type_t type, const void *data, size_t len, void *arg) {
 	const struct sockaddr_ll *from = arg;
 	const eth_addr_t *addr = (const eth_addr_t*)from->sll_addr;
@@ -263,6 +289,10 @@ static void handle_tlv(ffd_tlv_type_t type, const void *data, size_t len, void *
 		handle_tlv_ihu(data, len, addr, iface);
 		return;
 
+	case TLV_ANNOUNCE_REQ:
+		handle_tlv_announce_req(data, len, addr, iface);
+		return;
+
 	default:
 		fprintf(stderr, "debug: received unknown TLV %u on %s.\n", type, iface->name);
 		return;

ffd/ffd.h

@@ -41,13 +41,64 @@
 #define FFD_IHU_INTERVAL (3*FFD_HELLO_INTERVAL)
 
 
+typedef struct __attribute__((packed)) _ffd_node_id_t {
+	uint8_t id[8];
+} ffd_node_id_t;
+
+
+#define FFD_NODE_ID_UNSPEC ((ffd_node_id_t){})
+
+
+static inline bool ffd_is_node_id_unspec(const ffd_node_id_t *node) {
+	const uint8_t *id = node->id;
+
+	if (id[0]||id[1]||id[2]||id[3]||id[4]||id[5]||id[6]||id[7])
+		return false;
+	else
+		return true;
+}
+
+static inline bool ffd_are_node_ids_equal(const ffd_node_id_t *id1, const ffd_node_id_t *id2) {
+	const uint8_t *a = id1->id;
+	const uint8_t *b = id2->id;
+
+	return (a[0]==b[0] && a[1]==b[1] && a[2]==b[2] && a[3]==b[3]
+		&& a[4]==b[4] && a[5]==b[5] && a[6]==b[6] && a[7]==b[7]);
+}
+
+
+typedef struct _ffd_metric_seqno_t {
+	uint16_t metric;
+	uint16_t seqno;
+} ffd_metric_seqno_t;
+
+#define FFD_IS_INFINITY(m) ((m).metric == 0xffff)
+
+typedef struct _ffd_nexthop_t {
+	struct _ffd_nexthop_t *next;
+
+	struct timespec last_update;
+	eth_addr_t addr;
+	ffd_metric_seqno_t metric_seqno;
+} ffd_nexthop_t;
+
 typedef struct _ffd_announce_t {
 	struct _ffd_announce_t *next;
 
-	uint8_t type;
+	ffd_node_id_t node;
+	uint16_t type;
+	uint16_t key;
+	uint16_t interval;
+
 	uint8_t len;
+
+	ffd_metric_seqno_t feasability_distance;
+
+	ffd_nexthop_t *selected;
+	ffd_nexthop_t *nexthop_list;
+
 	uint8_t data[];
-} ffd_announce_head_t;
+} ffd_announce_t;
 
 typedef struct _ffd_neigh_t {
 	struct _ffd_neigh_t *next;
@@ -80,12 +131,17 @@ typedef struct _ffd_iface_t {
 extern const eth_addr_t ffd_addr;
 
 extern ffd_iface_t *iface_list;
+extern ffd_announce_t *announce_list;
 
 extern int sockfd;
 extern struct timespec now;
 
 
+ffd_metric_seqno_t ffd_announce_get_metric(const ffd_announce_t *announce);
+ffd_announce_t* ffd_announce_new();
+
 void ffd_send_hellos();
-void ffd_send_announce_request(ffd_iface_t *iface, ffd_neigh_t *neigh, void *announce);
+void ffd_send_update(ffd_iface_t *iface, ffd_neigh_t *neigh, const ffd_announce_t *announce);
+void ffd_send_announce_request(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_node_id_t node, uint16_t type, uint16_t key);
 
 #endif /* _FFD_FFD_H_ */

ffd/neigh.c

@@ -50,6 +50,9 @@ void ffd_neigh_free_list(ffd_neigh_t *neigh) {
 }
 
 uint16_t ffd_neigh_get_rxcost(const ffd_neigh_t *neigh) {
+	if (!neigh->hello_log || !neigh->hello_interval)
+		return 0xffff;
+
 	int timediff = timespec_diff(&now, &neigh->last_hello)/10;
 	int shift = (timediff - neigh->hello_interval/2)/neigh->hello_interval;
 	int received = __builtin_popcount(neigh->hello_log << shift);
@@ -74,5 +77,5 @@ uint16_t ffd_neigh_get_cost(const ffd_neigh_t *neigh) {
 }
 
 void ffd_neigh_reset(ffd_iface_t *iface, ffd_neigh_t *neigh) {
-	ffd_send_announce_request(iface, neigh, NULL);
+	ffd_send_announce_request(iface, neigh, FFD_NODE_ID_UNSPEC, 0, 0);
 }

ffd/send.c

@@ -116,6 +116,90 @@ void ffd_send_hellos() {
 	}
 }
 
-void ffd_send_announce_request(ffd_iface_t *iface, ffd_neigh_t *neigh, void *announce) {
+static bool add_node_id(ffd_packet_t *packet, size_t max_len, ffd_node_id_t node_id) {
+	ffd_tlv_node_id_t *tlv = ffd_tlv_add(packet, FFD_PACKET_MAX, TLV_NODE_ID, sizeof(ffd_tlv_node_id_t));
+	if (!tlv)
+		return false;
 
+	tlv->id = node_id;
+
+	return true;
+}
+
+static bool add_update(ffd_packet_t *packet, size_t max_len, ffd_node_id_t *node_id, const ffd_announce_t *announce) {
+	uint16_t len = packet->len;
+
+	if (!node_id || !ffd_are_node_ids_equal(node_id, &announce->node)) {
+		if (!add_node_id(packet, max_len, announce->node))
+			return false;
+
+		if (node_id)
+			*node_id = announce->node;
+	}
+
+	ffd_tlv_update_t *update = ffd_tlv_add(packet, FFD_PACKET_MAX, TLV_UPDATE, sizeof(ffd_tlv_update_t)+announce->len);
+	if (!update) {
+		packet->len = len;
+		return false;
+	}
+
+	ffd_metric_seqno_t metric = ffd_announce_get_metric(announce);
+
+	update->interval = htons(announce->interval);
+	update->seqno = htons(metric.seqno);
+	update->metric = htons(metric.metric);
+	update->type = htons(announce->type);
+	update->key = htons(announce->key);
+
+	memcpy(update->data, announce->data, announce->len);
+
+	return true;
+}
+
+void ffd_send_update(ffd_iface_t *iface, ffd_neigh_t *neigh, const ffd_announce_t *announce) {
+	ffd_packet_t *packet = alloca(sizeof(ffd_packet_t)+FFD_PACKET_MAX);
+
+	packet->version_magic = htons(FFD_VERSION_MAGIC);
+	packet->len = 0;
+
+	if (announce) {
+		add_update(packet, FFD_PACKET_MAX, NULL, announce);
+	}
+	else {
+		ffd_node_id_t node_id = FFD_NODE_ID_UNSPEC;
+
+		ffd_announce_t *a;
+		for (a = announce_list; a; a = a->next) {
+			if (!add_update(packet, FFD_PACKET_MAX, &node_id, a)) {
+				if (!send_eth(&ffd_addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
+					fprintf(stderr, "send_eth: %m\n");
+
+				node_id = FFD_NODE_ID_UNSPEC;
+				packet->len = 0;
+			}
+		}
+
+		if (packet->len) {
+			if (!send_eth(&ffd_addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
+				fprintf(stderr, "send_eth: %m\n");
+		}
+	}
+}
+
+void ffd_send_announce_request(ffd_iface_t *iface, ffd_neigh_t *neigh, ffd_node_id_t node, uint16_t type, uint16_t key) {
+	ffd_packet_t *packet = alloca(sizeof(ffd_packet_t)+FFD_PACKET_MAX);
+
+	packet->version_magic = htons(FFD_VERSION_MAGIC);
+	packet->len = 0;
+
+	ffd_tlv_announce_req_t *req = ffd_tlv_add(packet, FFD_PACKET_MAX, TLV_ANNOUNCE_REQ, sizeof(ffd_tlv_announce_req_t));
+	if (!req)
+		return;
+
+	req->node = node;
+	req->type = htons(type);
+	req->key = htons(key);
+
+	if (!send_eth(&ffd_addr, iface->ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
+		fprintf(stderr, "send_eth: %m\n");
 }

ffd/tlv_types.h

@@ -44,4 +44,30 @@ typedef struct __attribute__((packed)) _ffd_tlv_ihu_t {
 	uint8_t address[];
 } ffd_tlv_ihu_t;
 
+typedef struct __attribute__((packed)) _ffd_tlv_node_id_t {
+	ffd_node_id_t id;
+} ffd_tlv_node_id_t;
+
+typedef struct __attribute__((packed)) _ffd_tlv_update_t {
+	uint16_t interval;
+	uint16_t seqno;
+	uint16_t metric;
+	uint16_t type;
+	uint16_t key;
+	uint8_t data[];
+} ffd_tlv_update_t;
+
+typedef struct __attribute__((packed)) _ffd_tlv_announce_req_t {
+	ffd_node_id_t node;
+	uint16_t type;
+	uint16_t key;
+} ffd_tlv_announce_req_t;
+
+typedef struct __attribute__((packed)) _ffd_tlv_seqno_req_t {
+	ffd_node_id_t node;
+	uint16_t type;
+	uint16_t key;
+	uint16_t seqno;
+} ffd_tlv_seqno_req_t;
+
 #endif /* _FFD_TLV_TYPES_H_ */

ffd/types.h

@@ -33,7 +33,7 @@
 #include <net/ethernet.h>
 
 
-typedef struct __attribute__((__packed__)) _eth_addr_t {
+typedef struct __attribute__((packed)) _eth_addr_t {
 	uint8_t d[ETH_ALEN];
 } eth_addr_t;