[batman] add extra hop penalty if incoming and outcoming interface are the same wifi interface

Some setups use multiple radios link on different channels to increase the throughput. This patch allows batman to detect these setups.

git-svn-id: http://downloads.open-mesh.org/svn/batman/trunk/batman@1276 45894c77-fb22-0410-b583-ff6e7d5dbf6c

Author: marek

batman.h

@@ -86,10 +86,18 @@
 #define TQ_LOCAL_BIDRECT_RECV_MINIMUM 1
 #define TQ_TOTAL_BIDRECT_LIMIT 1
 
-#define TQ_HOP_PENALTY 10
+/**
+ * hop penalty is applied "twice"
+ * when the packet comes in and if rebroadcasted via the same interface
+ */
+#define TQ_HOP_PENALTY 5
 #define DEFAULT_ROUTING_CLASS 30
 
-#define MAX_AGGREGATION_BYTES 512   /* should not be bigger than 512 bytes or change the size of forw_node->direct_link_flags */
+/**
+ * should not be bigger than 512 bytes or change the size of
+ * forw_node->direct_link_flags and forw_node->in_if_num
+ */
+#define MAX_AGGREGATION_BYTES 512
 #define MAX_AGGREGATION_MS 100
 
 #define ROUTE_TYPE_UNICAST          0
@@ -248,6 +256,7 @@ struct forw_node                 /* structure for forw_list maintaining packets
 	unsigned char *pack_buff;
 	uint16_t  pack_buff_len;
 	uint32_t direct_link_flags;
+	uint8_t in_if_num[32];
 	uint8_t num_packets;
 	struct batman_if *if_outgoing;
 };
@@ -279,6 +288,7 @@ struct batman_if
 	struct sockaddr_in broad;
 	uint32_t netaddr;
 	uint8_t netmask;
+	uint8_t is_wifi_if;
 	struct bat_packet out;
 };
 

linux/kernel.c

@@ -28,13 +28,17 @@
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <inttypes.h>
+#include <net/if.h>
 
 #include "../os.h"
 #include "../batman.h"
 
 
 #define IOCGETNWDEV 1
 
+#ifndef SIOCGIWNAME
+#define SIOCGIWNAME 0x8B01
+#endif
 
 
 static int get_integer_file(const char* filename)
@@ -177,3 +181,20 @@ int32_t use_gateway_module(void)
 
 	return fd;
 }
+
+int is_wifi_interface(char *dev, int fd)
+{
+	struct ifreq int_req;
+	char *colon_ptr;
+
+	memset(&int_req, 0, sizeof (struct ifreq));
+	strncpy(int_req.ifr_name, dev, IFNAMSIZ - 1);
+
+	if ((colon_ptr = strchr(int_req.ifr_name, ':')) != NULL)
+		*colon_ptr = '\0';
+
+	if (ioctl(fd, SIOCGIWNAME, &int_req) >= 0)
+		return 1;
+
+	return 0;
+}

os.h

@@ -77,6 +77,7 @@ void set_forwarding( int32_t state );
 int32_t get_forwarding( void );
 int8_t bind_to_iface( int32_t sock, char *dev );
 int32_t use_gateway_module(void);
+int is_wifi_interface(char *dev, int fd);
 
 /* posix.c */
 void print_animation( void );

posix/init.c

@@ -919,8 +919,9 @@ static void activate_interface(struct batman_if *batman_if)
 #else
 	batman_if->if_index = 0;
 #endif
+	batman_if->is_wifi_if = is_wifi_interface(batman_if->dev, batman_if->udp_recv_sock);
 
-	if ( ioctl( batman_if->udp_recv_sock, SIOCGIFNETMASK, &int_req ) < 0 ) {
+	if (ioctl(batman_if->udp_recv_sock, SIOCGIFNETMASK, &int_req) < 0) {
 
 		debug_output(3, "Error - can't get netmask address of interface %s: %s\n", batman_if->dev, strerror(errno));
 		goto error;

schedule.c

@@ -49,6 +49,7 @@ void schedule_own_packet(struct batman_if *batman_if)
 	forw_node_new->own = 1;
 	forw_node_new->num_packets = 0;
 	forw_node_new->direct_link_flags = 0;
+	forw_node_new->in_if_num[forw_node_new->num_packets] = 255;
 
 	/* non-primary interfaces do not send hna information */
 	if ((num_hna_local > 0) && (batman_if->if_num == 0)) {
@@ -235,11 +236,14 @@ void schedule_forward_packet(struct orig_node *orig_node, struct bat_packet *in,
 
 	/* apply hop penalty */
 	bat_packet->tq = (bat_packet->tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE);
+
 	debug_output(4, "forwarding: tq_orig: %i, tq_avg: %i, tq_forw: %i, ttl_orig: %i, ttl_forw: %i \n", in->tq, tq_avg, bat_packet->tq, in->ttl - 1, bat_packet->ttl);
 
 	/* change sequence number to network order */
 	bat_packet->seqno = htons(bat_packet->seqno);
 
+	forw_node_new->in_if_num[forw_node_new->num_packets] = if_outgoing->if_num;
+
 	if (directlink)
 		bat_packet->flags = DIRECTLINK;
 	else
@@ -299,7 +303,6 @@ void send_outstanding_packets(uint32_t curr_time)
 		if (((directlink) && (bat_packet->ttl == 1)) ||
 			((forw_node->own) && (forw_node->if_outgoing->if_num > 0))) {
 
-
 			debug_output(4, "%s packet (originator %s, seqno %d, TTL %d) on interface %s\n", (forw_node->own ? "Sending own" : "Forwarding"), orig_str, ntohs(bat_packet->seqno), bat_packet->ttl, forw_node->if_outgoing->dev);
 
 			if (send_udp_packet(forw_node->pack_buff, forw_node->pack_buff_len, &forw_node->if_outgoing->broad, forw_node->if_outgoing->udp_send_sock, forw_node->if_outgoing) < 0)
@@ -328,7 +331,11 @@ void send_outstanding_packets(uint32_t curr_time)
 				if (curr_packet_num > 0)
 					addr_to_string(bat_packet->orig, orig_str, ADDR_STR_LEN);
 
-				debug_output(4, "%s %spacket (originator %s, seqno %d, TTL %d, IDF %s) on interface %s\n", (curr_packet_num > 0 ? "Forwarding" : (forw_node->own ? "Sending own" : "Forwarding")), (curr_packet_num > 0 ? "aggregated " : ""), orig_str, ntohs(bat_packet->seqno), bat_packet->ttl, (bat_packet->flags & DIRECTLINK ? "on" : "off"), batman_if->dev);
+				/* if the outgoing interface is a wifi interface and the incoming interface add extra penalty */
+				if ((batman_if->is_wifi_if) && (forw_node->in_if_num[curr_packet_num] == batman_if->if_num))
+					bat_packet->tq -= 2 * hop_penalty;
+
+				debug_output(4, "%s %spacket (originator %s, seqno %d, TQ %d, TTL %d, IDF %s) on interface %s\n", (curr_packet_num > 0 ? "Forwarding" : (forw_node->own ? "Sending own" : "Forwarding")), (curr_packet_num > 0 ? "aggregated " : ""), orig_str, ntohs(bat_packet->seqno), bat_packet->tq, bat_packet->ttl, (bat_packet->flags & DIRECTLINK ? "on" : "off"), batman_if->dev);
 
 				curr_packet_len += sizeof(struct bat_packet) + bat_packet->hna_len * 5;
 				curr_packet_num++;