1 files changed, 264 insertions, 0 deletions
diff --git a/ax25ipd/routing.c b/ax25ipd/routing.c
new file mode 100644
index 0000000..3f771b3
--- /dev/null
+++ b/ax25ipd/routing.c
@@ -0,0 +1,264 @@
+/* routing.c    Routing table manipulation routines
+ *
+ * Copyright 1991, Michael Westerhof, Sun Microsystems, Inc.
+ * This software may be freely used, distributed, or modified, providing
+ * this header is not removed.
+ *
+ */
+
+#include <stdio.h>
+#include "ax25ipd.h"
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <memory.h>
+
+/* The routing table structure is not visible outside this module. */
+
+struct route_table_entry {
+	unsigned char callsign[7];		/* the callsign and ssid */
+	unsigned char padcall;			/* always set to zero */
+	unsigned char ip_addr[4];		/* the IP address */
+	unsigned short udp_port;		/* the port number if udp */
+	unsigned char pad1;
+	unsigned char pad2;
+	unsigned int flags;			/* route flags */
+	struct route_table_entry* next;
+};
+
+struct route_table_entry* route_tbl;
+struct route_table_entry* default_route;
+
+/* The Broadcast address structure is not visible outside this module either */
+
+struct bcast_table_entry {
+	unsigned char callsign[7];		/* The broadcast address */
+	struct bcast_table_entry* next;
+};
+
+struct bcast_table_entry* bcast_tbl;
+
+/* Initialize the routing module */
+void
+route_init()
+{
+	route_tbl = NULL;
+	default_route = NULL;
+	bcast_tbl = NULL;
+}
+
+/* Add a new route entry */
+void
+route_add(ip, call, udpport, flags)
+unsigned char *ip;
+unsigned char *call;
+int udpport;
+unsigned int flags;
+{
+	struct route_table_entry *rl, *rn;
+	int i;
+
+	/* Check we have an IP address */
+	if (ip==NULL)
+		return;
+
+	/* Check we have a callsign */
+	if (call==NULL)
+		return;
+
+	/* Find the last entry in the list */
+	rl=route_tbl;
+	if (route_tbl)
+		while (rl->next)
+			rl=rl->next;
+
+	rn=(struct route_table_entry*)malloc(sizeof(struct route_table_entry));
+
+	/* Build this entry ... */
+	for (i=0; i<6; i++)
+		rn->callsign[i] = call[i] & 0xfe;
+	rn->callsign[6] = (call[6] & 0x1e) | 0x60;
+	rn->padcall = 0;
+	memcpy(rn->ip_addr, ip, 4);
+	rn->udp_port = htons(udpport);
+	rn->pad1 = 0;
+	rn->pad2 = 0;
+	rn->flags = flags;
+	rn->next=NULL;
+
+	/* Update the default_route pointer if this is a default route */
+	if (flags & AXRT_DEFAULT)
+		default_route=rn;
+
+	if (rl)	/* ... the list is already started add the new route */
+		rl->next=rn;
+	else	/* ... start the list off */
+		route_tbl=rn;
+
+	/* Log this entry ... */
+	LOGL4("added route: %s\t%s\t%s\t%d\t%d\n",
+			call_to_a(rn->callsign),
+			(char *)inet_ntoa(*(struct in_addr *)rn->ip_addr),
+			rn->udp_port ? "udp" : "ip",
+			ntohs(rn->udp_port), flags);
+
+	return;
+}
+
+/* Add a new broadcast address entry */
+void
+bcast_add(call)
+unsigned char* call;
+{
+	struct bcast_table_entry *bl, *bn;
+	int i;
+
+	/* Check we have a callsign */
+	if (call==NULL)
+		return;
+
+	/* Find the last entry in the list */
+	bl=bcast_tbl;
+	if (bcast_tbl)
+		while (bl->next)
+			bl=bl->next;
+
+	bn=(struct bcast_table_entry*)malloc(sizeof(struct bcast_table_entry));
+
+	/* Build this entry ... */
+	for (i=0; i<6; i++)
+		bn->callsign[i] = call[i] & 0xfe;
+	bn->callsign[6] = (call[6] & 0x1e) | 0x60;
+
+	bn->next=NULL;
+
+	if (bl)	/* ... the list is already started add the new route */
+		bl->next=bn;
+	else	/* ... start the list off */
+		bcast_tbl=bn;
+
+	/* Log this entry ... */
+	LOGL4("added broadcast address: %s\n", call_to_a(bn->callsign));
+}
+
+/*
+ * Return an IP address and port number given a callsign.
+ * We return a pointer to the address; the port number can be found
+ * immediately following the IP address. (UGLY coding; to be fixed later!)
+ */
+
+unsigned char *
+call_to_ip(call)
+unsigned char *call;
+{
+	struct route_table_entry* rp;
+	unsigned char mycall[7];
+	int i;
+
+	if(call==NULL)
+		return NULL;
+
+	for(i=0; i<6; i++)
+		mycall[i] = call[i] & 0xfe;
+
+	mycall[6] = (call[6] & 0x1e) | 0x60;
+
+	LOGL4("lookup call %s ",call_to_a(mycall));
+
+	rp=route_tbl;
+	while (rp) {
+		if (addrmatch(mycall,rp->callsign)) {
+			LOGL4("found ip addr %s\n",
+				(char *)inet_ntoa(*(struct in_addr *)rp->ip_addr));
+			return rp->ip_addr;
+		}
+		rp=rp->next;
+	}
+
+	/*
+	 * No match found in the routing table, use the default route if
+	 * we have one defined.
+	 */
+	if (default_route) {
+		LOGL4("failed, using default ip addr %s\n",
+				(char *)inet_ntoa(*(struct in_addr *)default_route->ip_addr));
+		return default_route->ip_addr;
+	}
+
+	LOGL4("failed.\n");
+	return NULL;
+}
+
+/*
+ * Accept a callsign and return true if it is a broadcast address, or false
+ * if it is not found on the list
+ */
+int
+is_call_bcast(call)
+unsigned char *call;
+{
+	struct bcast_table_entry* bp;
+	unsigned char bccall[7];
+	int i;
+
+	if(call==NULL)
+		return(FALSE);
+
+	for(i=0; i<6; i++)
+		bccall[i] = call[i] & 0xfe;
+
+	bccall[6] = (call[6] & 0x1e) | 0x60;
+
+	LOGL4("lookup broadcast %s ",call_to_a(bccall));
+
+	bp=bcast_tbl;
+	while (bp) {
+		if (addrmatch(bccall,bp->callsign)) {
+			LOGL4("found broadcast %s\n", call_to_a(bp->callsign));
+			return(TRUE);
+		}
+		bp=bp->next;
+	}
+	return(FALSE);
+}
+
+/* Traverse the routing table, transmitting the packet to each bcast route */
+void
+send_broadcast(buf, l)
+unsigned char *buf;
+int l;
+{
+	struct route_table_entry *rp;
+
+	rp=route_tbl;
+	while (rp) {
+		if (rp->flags & AXRT_BCAST) {
+			send_ip(buf, l, rp->ip_addr);
+		}
+		rp=rp->next;
+	}
+}
+
+/* print out the list of routes */
+void
+dump_routes()
+{
+	struct route_table_entry* rp;
+	int i;
+
+	for (rp=route_tbl, i=0; rp; rp=rp->next)
+		i++;
+
+	LOGL1("\n%d active routes.\n",i);
+
+	rp=route_tbl;
+	while (rp) {
+		LOGL1("  %s\t%s\t%s\t%d\t%d\n",
+			call_to_a(rp->callsign),
+			(char *)inet_ntoa(*(struct in_addr *)rp->ip_addr),
+			rp->udp_port ? "udp" : "ip",
+			ntohs(rp->udp_port), rp->flags);
+		rp=rp->next;
+	}
+	fflush(stdout);
+}
+