Lots of bugfixes, correctly handle announcements

ffvisd/ffvisd.c

@@ -126,6 +126,13 @@ static const eth_addr_t eth_addr_unspec = {{0x00, 0x00, 0x00, 0x00, 0x00, 0x00}}
 static const eth_addr_t ffd_addr = {{0x03, 0x00, 0x00, 0x00, 0x0f, 0xfd}};
 
 
+static int sockfd;
+static char *mesh = "bat0";
+
+static struct timespec now;
+static ffvisd_announce_t *announcements = NULL;
+
+
 static inline bool is_eth_addr_unspec(const eth_addr_t *address) {
 	const uint8_t *a = address->address;
 
@@ -135,16 +142,19 @@ static inline bool is_eth_addr_unspec(const eth_addr_t *address) {
 		return true;
 }
 
+static inline bool are_eth_addrs_equal(const eth_addr_t *address1, const eth_addr_t *address2) {
+	const uint8_t *a = address1->address;
+	const uint8_t *b = address2->address;
 
-#define ETH_ADDR_IS_UNSPEC(a) (!((a).address[0]||(a).address[0]||(a).address[0]||(a).address[0]||(a).address[0]||(a).address[0]))
+	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]);
+}
 
+static inline bool are_ipv6_host_addrs_equal(const ffvisd_ipv6_host_addr_t *address1, const ffvisd_ipv6_host_addr_t *address2) {
+	const uint8_t *a = address1->address;
+	const uint8_t *b = address2->address;
 
-static int sockfd;
+	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]);
-static char *mesh = "bat0";
+}
-
-
-ffvisd_announce_t *announcements = NULL;
-
 
 /* returns (tp1 - tp2) in milliseconds  */
 static inline int timespec_diff(const struct timespec *tp1, const struct timespec *tp2) {
@@ -152,6 +162,23 @@ static inline int timespec_diff(const struct timespec *tp1, const struct timespe
 }
 
 
+static inline bool are_announcements_equal(const ffvisd_packet_server_announce_t *a1, const ffvisd_packet_server_announce_t *a2) {
+	return (are_eth_addrs_equal(&a1->eth_address, &a2->eth_address) && are_ipv6_host_addrs_equal(&a1->address, &a2->address));
+}
+
+static inline bool is_announcement_local(const ffvisd_announce_t *a) {
+	return (a->received.tv_sec == 0);
+}
+
+static inline bool is_announcement_valid(const ffvisd_announce_t *a) {
+	if (is_announcement_local(a))
+		return true;
+
+	int diff = timespec_diff(&now, &a->received);
+	return (diff < ANNOUNCE_TIMEOUT*1000);
+}
+
+
 static bool file_readv(const char *file, const char *format, va_list ap) {
 	FILE *f = fopen(file, "r");
 	if (!f)
@@ -322,13 +349,13 @@ static void pr_announcement_packet(const ffvisd_packet_server_announce_t *announ
 	const uint8_t *e = announce->eth_address.address, *a = announce->address.address;
 
 	printf("seqno: %u, ether: %02x:%02x:%02x:%02x:%02x:%02x, address: fe80::%02x%02x:%02x%02x:%02x%02x:%02x%02x\n",
-	       announce->seqno,
+	       ntohs(announce->seqno),
 	       e[0], e[1], e[2], e[3], e[4], e[5],
 	       a[0], a[1], a[2], a[3], a[4], a[5], a[6], a[7]);
 }
 
 static void pr_announcement(const ffvisd_announce_t *announce) {
-	if (!announce->received.tv_sec) {
+	if (is_announcement_local(announce)) {
 		printf("local, ");
 	}
 	else {
@@ -337,6 +364,8 @@ static void pr_announcement(const ffvisd_announce_t *announce) {
 		printf("age: %.1fs, ", timespec_diff(&tv, &announce->received)/1000.0);
 	}
 
+	printf("valid: %s, ", is_announcement_valid(announce) ? "yes" : "no");
+
 	pr_announcement_packet(&announce->announce);
 }
 
@@ -394,15 +423,34 @@ static bool init_announcements() {
 }
 
 static void maintenance() {
-	ffvisd_announce_t **announce;
+	clock_gettime(CLOCK_MONOTONIC, &now);
 
-	for(announce = &announcements; *announce; announce = &(*announce)->next) {
+	ffvisd_announce_t **announce, **next;
-		if (!(*announce)->received.tv_sec) /* announcement is local */
+
+	for(announce = &announcements; *announce; announce = next) {
+		next = &(*announce)->next;
+
+		if (is_announcement_local(*announce)) {
 			(*announce)->announce.seqno = htons(ntohs((*announce)->announce.seqno)+1);
+			continue;
+		}
+
+		int diff = timespec_diff(&now, &(*announce)->received);
+		if (diff >= ANNOUNCE_PRUNE*1000) {
+			ffvisd_announce_t *del = *announce;
+
+			*announce = *next;
+			next = announce;
+
+			free(del);
+		}
 	}
 }
 
 static void send_announcement(const char *ifname, unsigned ifindex, void *arg) {
+	char *if_mesh = iface_get_mesh(ifname);
+
+	if (if_mesh && !strcmp(if_mesh, mesh)) {
 		ffvisd_packet_announce_t *packet = arg;
 
 		struct sockaddr_ll sa;
@@ -415,6 +463,8 @@ static void send_announcement(const char *ifname, unsigned ifindex, void *arg) {
 		memcpy(sa.sll_addr, ffd_addr.address, ETH_ALEN);
 
 		sendto(sockfd, packet, sizeof(ffvisd_packet_announce_t) + ntohs(packet->n_servers)*sizeof(ffvisd_packet_server_announce_t), 0, (struct sockaddr*)&sa, sizeof(sa));
+	}
+	free(if_mesh);
 }
 
 static void send_announcements() {
@@ -427,6 +477,9 @@ static void send_announcements() {
 	uint16_t n_servers = 0;
 	ffvisd_announce_t *announce;
 	for(announce = announcements; announce; announce = announce->next) {
+		if (!is_announcement_valid(announce))
+			continue;
+
 		packet->servers[n_servers++] = announce->announce;
 	}
 
@@ -462,6 +515,38 @@ static void receive_announcement() {
 	for(i = 0; i < n_servers; i++)
 		pr_announcement_packet(&packet->servers[i]);
 	puts("");
+
+	clock_gettime(CLOCK_MONOTONIC, &now);
+
+	for(i = 0; i < n_servers; i++) {
+		ffvisd_announce_t *announce;
+		for(announce = announcements; announce; announce = announce->next) {
+			if (!are_announcements_equal(&packet->servers[i], &announce->announce))
+				continue;
+
+			if (is_announcement_local(announce))
+				break;
+
+			uint16_t seqno_diff = ntohs(packet->servers[i].seqno) - ntohs(announce->announce.seqno);
+
+			if (seqno_diff > 0 && seqno_diff < 0x8000) {
+				announce->received = now;
+				announce->announce = packet->servers[i];
+			}
+
+			break;
+		}
+
+		if (!announce) { /* no matching annouce was found */
+			announce = calloc(1, sizeof(ffvisd_announce_t));
+			announce->received = now;
+			announce->announce = packet->servers[i];
+
+			announce->next = announcements;
+			announcements = announce;
+		}
+
+	}
 }
 
 int main() {
@@ -493,7 +578,6 @@ int main() {
 		next_announce.tv_sec += ANNOUNCE_INTERVAL;
 
 		while (true) {
-			struct timespec now;
 			clock_gettime(CLOCK_MONOTONIC, &now);
 			int timeout = timespec_diff(&next_announce, &now);