Send hello packets

ffd/ffd.c

@@ -27,6 +27,8 @@
 #include "ffd.h"
 #include "netif.h"
 #include "packet.h"
+#include "tlv.h"
+#include "tlv_types.h"
 
 #include <errno.h>
 #include <poll.h>
@@ -46,6 +48,7 @@
 static const eth_addr_t ffd_addr = {{0x03, 0x00, 0x00, 0x00, 0x0f, 0xfd}};
 
 #define HELLO_INTERVAL 10
+#define PACKET_MAX 1000
 
 
 static char *mesh = "bat0";
@@ -161,19 +164,28 @@ static void send_hello(const char *ifname, unsigned ifindex, void *arg) {
 
 	ffd_packet_t *packet = arg;
 
-	if (!send_eth(&ffd_addr, ifindex, packet, sizeof(ffd_packet_t)+packet->len))
+	if (!send_eth(&ffd_addr, ifindex, packet, sizeof(ffd_packet_t)+ntohs(packet->len)))
 		fprintf(stderr, "send_eth: %m\n");
 }
 
 static void send_hellos() {
 	/*if (!orig_data)
 	  return;*/
+	static uint16_t seqno = 0;
 
-	ffd_packet_t *packet = alloca(sizeof(ffd_packet_t)+1000);
+	ffd_packet_t *packet = alloca(sizeof(ffd_packet_t)+PACKET_MAX);
 
 	packet->version_magic = htons(FFD_VERSION_MAGIC);
 	packet->len = 0;
 
+	ffd_tlv_hello_t *hello = ffd_tlv_add(packet, PACKET_MAX, TLV_HELLO, sizeof(ffd_tlv_hello_t));
+	if (!hello)
+		return;
+
+	memset(hello, 0, sizeof(ffd_tlv_hello_t));
+	hello->seqno = htons(seqno++);
+	hello->interval = htons(HELLO_INTERVAL*100);
+
 	netif_foreach(send_hello, packet);
 }
 

ffd/tlv.c

@@ -32,14 +32,14 @@
 #include <arpa/inet.h>
 
 
-bool ffd_tlv_parse(const ffd_packet_t *packet, ffd_tlv_cb cb) {
+bool ffd_tlv_parse(const ffd_packet_t *packet, ffd_tlv_cb cb, void *arg) {
 	if (packet->version_magic != htons(FFD_VERSION_MAGIC))
 		return false;
 
-	const uint8_t *data = packet->tlv + 2, *end = ((uint8_t*)packet->tlv) + packet->len;
+	const uint8_t *data = packet->tlv + 2, *end = packet->tlv + packet->len;
 
 	while (data <= end) {
-		if (!data[-2]) {
+		if (data[-2] == TLV_PAD1) {
 			/* Pad1 */
 			data++;
 			continue;
@@ -50,24 +50,27 @@ bool ffd_tlv_parse(const ffd_packet_t *packet, ffd_tlv_cb cb) {
 			break;
 		}
 
-		cb(data[-2], data, data[-1]);
+		if (data[-2] != TLV_PADN)
+			cb(data[-2], data, data[-1], arg);
+
 		data += data[-1] + 2;
 	}
 
 	return true;
 }
 
-bool ffd_tlv_add(ffd_packet_t *packet, size_t max_len, ffd_tlv_type_t type, void *data, size_t len) {
-	if (ntohs(packet->len)+len+2 > max_len)
-		return false;
+void* ffd_tlv_add(ffd_packet_t *packet, size_t max_len, ffd_tlv_type_t type, size_t len) {
+	size_t pktlen = ntohs(packet->len);
 
-	packet->len = htons(ntohs(packet->len)+len+2);
+	if (pktlen+len+2 > max_len)
+		return NULL;
 
-	uint8_t *pkgdata = packet->tlv;
+	uint8_t *data = packet->tlv+pktlen+2;
 
-	pkgdata[0] = type;
-	pkgdata[1] = len;
-	memcpy(pkgdata+2, data, len);
+	data[-2] = type;
+	data[-1] = len;
 
-	return true;
+	packet->len = htons(pktlen+len+2);
+
+	return data;
 }

ffd/tlv.h

@@ -33,14 +33,23 @@
 typedef enum _ffd_tlv_type_t {
 	TLV_PAD1 = 0,
 	TLV_PADN,
+	TLV_ACK_REQ,
+	TLV_ACK,
+	TLV_HELLO,
+	TLV_IHU,
+	TLV_NODE_ID,
+	TLV_RESERVED,
+	TLV_UPDATE,
+	TLV_INFO_REQ,
+	TLV_SEQNO_REQ,
 } ffd_tlv_type_t;
 
 
-typedef void (*ffd_tlv_cb)(ffd_tlv_type_t type, const void *data, size_t len);
+typedef void (*ffd_tlv_cb)(ffd_tlv_type_t type, const void *data, size_t len, void *arg);
 
 
-bool ffd_tlv_parse(const ffd_packet_t *packet, ffd_tlv_cb cb);
-bool ffd_tlv_add(ffd_packet_t *packet, size_t max_len, ffd_tlv_type_t type, void *data, size_t len);
+bool ffd_tlv_parse(const ffd_packet_t *packet, ffd_tlv_cb cb, void *arg);
+void* ffd_tlv_add(ffd_packet_t *packet, size_t max_len, ffd_tlv_type_t type, size_t len);
 
 
 #endif /* _FFD_TLV_H_ */

ffd/tlv_types.h

@@ -0,0 +1,39 @@
+/*
+  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.
+*/
+
+
+#ifndef _FFD_TLV_TYPES_H_
+#define _FFD_TLV_TYPES_H_
+
+#include "tlv.h"
+
+
+typedef struct __attribute__((packed)) _ffd_tlv_hello_t {
+	uint16_t reserved;
+	uint16_t seqno;
+	uint16_t interval;
+} ffd_tlv_hello_t;
+
+#endif /* _FFD_TLV_TYPES_H_ */