1 files changed, 105 insertions, 31 deletions

diff --git a/netrom/netromr.c b/netrom/netromr.c
index 90e775a..3ba7c33 100644
--- a/netrom/netromr.c
+++ b/netrom/netromr.c
@@ -1,7 +1,8 @@
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
 #include <unistd.h>
+#include <ctype.h>
+#include <string.h>
 #include <syslog.h>
 
 #include <config.h>
@@ -37,6 +38,28 @@
 
 extern int compliant;
 
+static int validcallsign(ax25_address *a)
+{
+	char c;
+	int n, end = 0;
+
+	for (n = 0; n < 6; n++) {
+		c = (a->ax25_call[n] >> 1) & 0x7F;
+
+		if (!end && (isupper(c) || isdigit(c)))
+			continue;
+
+		if (c == ' ') {
+			end = 1;
+			continue;
+		}
+
+		return FALSE;
+        }
+
+	return TRUE;
+}
+
 static int validmnemonic(char *mnemonic)
 {
 	if (compliant) {
@@ -50,6 +73,73 @@ static int validmnemonic(char *mnemonic)
 	return FALSE;
 }
 
+static int add_node(int s, unsigned char *buffer, struct nr_route_struct *nr_node, int quality, int index)
+{
+	ax25_address best_neighbour;
+	int best_quality;
+	char *p;
+
+	memcpy(&nr_node->callsign, buffer + 0,  CALLSIGN_LEN);
+	memcpy(nr_node->mnemonic,  buffer + 7,  MNEMONIC_LEN);
+	memcpy(&best_neighbour,    buffer + 13, CALLSIGN_LEN);
+
+	best_quality = buffer[20];
+
+	nr_node->mnemonic[MNEMONIC_LEN] = '\0';
+	if ((p = strchr(nr_node->mnemonic, ' ')) != NULL)
+		*p = '\0';
+
+	if (!validcallsign(&nr_node->callsign)) {
+		if (debug && logging)
+			syslog(LOG_DEBUG, "netromr: add_node: invalid node callsign - %s", ax25_ntoa(&nr_node->callsign));
+		return -1;
+	}
+
+	if (!validmnemonic(nr_node->mnemonic)) {
+		if (debug && logging)
+			syslog(LOG_DEBUG, "netromr: add_node: invalid mnemonic - %s", nr_node->mnemonic);
+		return -1;
+	}
+
+	if (!validcallsign(&best_neighbour)) {
+		if (debug && logging)
+			syslog(LOG_DEBUG, "netromr: add_node: invalid best neighbour callsign - %s", &best_neighbour);
+		return -1;
+	}
+
+	if (ax25_cmp(&my_call, &best_neighbour) == 0) {
+		if (debug && logging)
+			syslog(LOG_DEBUG, "netromr: add_node: route to me");
+		return FALSE;
+	}
+
+	if (best_quality < port_list[index].worst_qual) {
+		if (debug && logging)
+			syslog(LOG_DEBUG, "netromr: add_node: quality less than worst_qual");
+		return FALSE;
+	}
+
+	nr_node->quality = ((quality * best_quality) + 128) / 256;
+
+	/* log this only when logging verbosely */
+	if (debug > 1 && logging) {
+		syslog(LOG_DEBUG, "Node update: %s:%s",
+		       ax25_ntoa(&nr_node->callsign), nr_node->mnemonic);
+		syslog(LOG_DEBUG, "Neighbour: %s device: %s",
+		       ax25_ntoa(&nr_node->neighbour), nr_node->device);
+		syslog(LOG_DEBUG, "Quality: %d obs: %d ndigis: %d",
+		       nr_node->quality, nr_node->obs_count, nr_node->ndigis);
+	}
+
+	if (ioctl(s, SIOCADDRT, nr_node) == -1) {
+		if (logging)
+			syslog(LOG_ERR, "netromr: SIOCADDRT: %m");
+		return -1;
+	}
+
+	return TRUE;
+}
+
 void receive_nodes(unsigned char *buffer, int length, ax25_address *neighbour, int index)
 {
 	struct nr_route_struct nr_node;
@@ -59,8 +149,14 @@ void receive_nodes(unsigned char *buffer, int length, ax25_address *neighbour, i
 	int quality, obs_count, qual, lock;
 	char *addr, *callsign, *device;
 
+	if (!validcallsign(neighbour)) {
+		if (debug && logging)
+			syslog(LOG_DEBUG, "rejecting frame, invalid neighbour callsign - %s\n", ax25_ntoa(neighbour));
+		return;
+	}
+
 	nr_node.type   = NETROM_NODE;
-	/*nr_node.ndigis = 0;*/
+	nr_node.ndigis = 0;
 
 	sprintf(neigh_buffer, "%s/obsolescence_count_initialiser", PROC_NR_SYSCTL_DIR);
 
@@ -140,35 +236,13 @@ void receive_nodes(unsigned char *buffer, int length, ax25_address *neighbour, i
 	length -= MNEMONIC_LEN;
 
 	while (length >= ROUTE_LEN) {
-		/*
-		 * Ensure that a) the route is not via me, and
-		 *             b) it is better than my minimum acceptable quality
-		 */
-		if (ax25_cmp(&my_call, (ax25_address *)(buffer + 13)) != 0 &&
-		    buffer[20] > port_list[index].worst_qual) {
-			memcpy(&nr_node.callsign, buffer + 0, CALLSIGN_LEN);
-			memcpy(nr_node.mnemonic,  buffer + 7, MNEMONIC_LEN);
-			nr_node.mnemonic[MNEMONIC_LEN] = '\0';
-
-			if ((p = strchr(nr_node.mnemonic, ' ')) != NULL)
-				*p = '\0';
-
-			if (!validmnemonic(nr_node.mnemonic)) {
-				if (debug && logging)
-					syslog(LOG_DEBUG, "rejecting route, invalid mnemonic - %s\n", nr_node.mnemonic);
-			} else {
-				nr_node.neighbour   = *neighbour;
-				strcpy(nr_node.device, port_list[index].device);
-				nr_node.quality     = ((quality * buffer[20]) + 128) / 256;
-				nr_node.obs_count   = obs_count;
-
-				if (ioctl(s, SIOCADDRT, &nr_node) == -1) {
-					if (logging)
-						syslog(LOG_ERR, "netromr: SIOCADDRT: %m");
-					close(s);
-					return;
-				}
-			}
+		nr_node.neighbour   = *neighbour;
+		strcpy(nr_node.device, port_list[index].device);
+		nr_node.obs_count   = obs_count;
+
+		if (add_node(s, buffer, &nr_node, quality, index) == -1) {
+			close(s);
+			return;
 		}
 
 		buffer += ROUTE_LEN;