Some work on the ipv6->eth sending side (not a compilable commit)

Just initial work. Still need to get the NDP solicitations getting sent to do 
the ipv6 -> MAC translations, and then more work to get the upper layer TCP
and UDP handlers to work right without referencing ip_hdr all over the place.

Ticket #42

arp.c

@@ -91,6 +91,7 @@
 #include "arp.h"
 #include "debug.h"
 
+/* Time in seconds before expiration of ARP entries */
 #define ARP_MAX_ACTIVE		600
 
 /* Exported */

honeyd.c

@@ -594,29 +594,58 @@ honeyd_ether_cb(struct arp_req *req, int success, void *arg)
 void
 honeyd_deliver_ethernet(struct interface *inter,
     struct addr *src_pa, struct addr *src_ha,
-    struct addr *dst_pa, struct ip_hdr *ip, u_int iplen)
+    struct addr *dst_pa, u_char *frameData, u_int frameLength)
 {
-	struct arp_req *req;
+	if (src_pa->addr_type == ADDR_TYPE_IP)
+	{
+		struct ip_hdr *ip = (struct ip_hdr*)frameData;
+		struct arp_req *req;
 
-	ip_checksum(ip, iplen);
+		ip_checksum(ip, frameLength);
 
-	/* Ethernet delivery if possible */
-	if ((req = arp_find(dst_pa)) == NULL) {
-		arp_request(inter, src_pa, src_ha, dst_pa, honeyd_ether_cb,ip);
-	} else if (req->cnt == -1) {
-		/*
-		 * The source MAC of the original requestor does not help
-		 * us here, but we can overwrite it with the MAC of this
-		 * honeypot without causing any harm.
-		 */
-		req->src_ha = *src_ha;
-		honeyd_ether_cb(req, 1, ip);
-	} else {
-		/* 
-		 * Fall through in case that this packet needs
-		 * to be dropped.
-		 */
-		pool_free(pool_pkt, ip);
+		/* Ethernet delivery if possible */
+		if ((req = arp_find(dst_pa)) == NULL) {
+			arp_request(inter, src_pa, src_ha, dst_pa, honeyd_ether_cb,ip);
+		} else if (req->cnt == -1) {
+			/*
+			 * The source MAC of the original requestor does not help
+			 * us here, but we can overwrite it with the MAC of this
+			 * honeypot without causing any harm.
+			 */
+			req->src_ha = *src_ha;
+			honeyd_ether_cb(req, 1, ip);
+		} else {
+			/*
+			 * Fall through in case that this packet needs
+			 * to be dropped.
+			 */
+			pool_free(pool_pkt, ip);
+		}
+	} else if (src_pa->addr_type == ADDR_TYPE_IP6) {
+		// TODO ipv6 Do the neighbor solicitation here, send to the ether
+		struct ip6_hdr *ip6 = (struct ip6_hdr*)ip6;
+		struct ndp_req *req;
+
+		ip6_checksum(ip6, frameLength);
+
+		if ((req = ndp_find(dst_pa)) == NULL)
+		{
+			ndp_request(inter, src_pa, src_ha, dst_pa, honeyd_ether_cb,ip6);
+		} else if (req->cnt == -1) {
+			/*
+			 * The source MAC of the original requestor does not help
+			 * us here, but we can overwrite it with the MAC of this
+			 * honeypot without causing any harm.
+			 */
+			req->src_ha = *src_ha;
+			//honeyd_ether_cb(req, 1, ip);
+		} else {
+			/*
+			 * Fall through in case that this packet needs
+			 * to be dropped.
+			 */
+			pool_free(pool_pkt, ip6);
+		}
 	}
 }
 
@@ -721,7 +750,7 @@ honeyd_delay_cb(int fd, short which, void *arg)
 			/* This function computes the IP checksum for us */
 			honeyd_deliver_ethernet(tmpl->inter,
 			    &src, tmpl->ethernet_addr,
-			    &dst, ip, iplen);
+			    &dst, (u_char*)ip, iplen);
 		} else {
 			honeyd_send_normally(ip, iplen);
 		}
@@ -761,7 +790,7 @@ honeyd_delay_cb(int fd, short which, void *arg)
 		/* This function computes the IP checksum for us */
 		honeyd_deliver_ethernet(inter,
 		    &router->addr, &inter->if_ent.intf_link_addr,
-		    &addr, ip, iplen);
+		    &addr, (u_char*)ip, iplen);
 	} else {
 		struct addr addr;
 		uint16_t ipoff;

icmpv6.h

@@ -17,6 +17,8 @@
 
 #define ICMPV6_HDR_LEN	4	/* base ICMPv6 header length */
 
+#define ICMPV6_ND_PAYLOAD_LEN 32 /* length of icmpv6 neighbor discovery/advertisement with target MAC option */
+
 #ifndef __GNUC__
 #ifndef __attribute__
 # define __attribute__(x)

ndp.c

@@ -67,9 +67,12 @@
 
 #include "debug.h"
 
+#define NDP_MAX_ACTIVE 600
+
 /* For the physical (IP) address */
 static SPLAY_HEAD(ndpTree, ndp_req) pa_ndp_reqs;
 
+/* Just for ordering the SPLAY tree */
 static int
 pandp_compare(struct ndp_req *a, struct ndp_req *b)
 {
@@ -140,23 +143,63 @@ ndp_new(struct interface *inter,
 	return (req);
 }
 
-void ndp_send_advertisement(eth_t *eth,
+/* Request resulution ofi pv6 address into a MAC via a neighbor solicitation */
+void
+ndp_request(struct interface *inter,
+    struct addr *src_pa, struct addr *src_ha,
+    struct addr *addr, void (*cb)(struct ndp_req *, int, void *), void *arg)
+{
+	struct ndp_req *req;
+	struct addr bcast;
+	struct timeval tv;
+
+	if ((req = ndp_new(inter, src_pa, src_ha, addr, NULL)) == NULL) {
+		syslog(LOG_ERR, "calloc: %m");
+		return;
+	}
+
+	req->cb = cb;
+	req->arg = arg;
+
+
+	// TODO ipv6 !!!!
+
+	// Need to trace figure out what to do with this stuff
+	timerclear(&tv);
+	tv.tv_sec = NDP_MAX_ACTIVE;
+	evtimer_add(&req->active, &tv);
+
+	addr_pack(&bcast, ADDR_TYPE_ETH, ETH_ADDR_BITS,
+	    ETH_ADDR_BROADCAST, ETH_ADDR_LEN);
+	arp_discover(req, &bcast);
+
+	// TODO ipv6 !!!!
+}
+
+void ndp_send(eth_t *eth, uint icmpv6MessageType,
     struct addr linkLayerSource, struct addr linkLayerDestination,
     struct addr ipLayerSource, struct addr ipLayerDestination,
-    struct addr advertisementLinkTarget, struct addr advertisementIpTarget)
+    struct addr linkLayerTarget, struct addr ipLayerTarget)
 {
 
-	printf("Ndp advertisement details {\nipLayerSource: %s\nipLayerDestination: %s \nadvertisementLinkTarget: %s\nadvertisementIpTarget: %s\n}\n", addr_ntoa(&ipLayerSource), addr_ntoa(&ipLayerDestination), addr_ntoa(&advertisementLinkTarget), addr_ntoa(&advertisementIpTarget));
 	uint packetLength = ETH_HDR_LEN + IP6_HDR_LEN + ICMPV6_HDR_LEN + sizeof(struct icmpv6_msg_nd);
 	u_char pkt[packetLength];
 
 	eth_pack_hdr(pkt, linkLayerDestination.addr_eth, linkLayerSource.addr_eth, ETH_TYPE_IPV6);
-	ip6_pack_hdr(pkt + ETH_HDR_LEN, 0, 0, 32, IP_PROTO_ICMPV6, IP6_HLIM_MAX, ipLayerSource.addr_ip6, ipLayerDestination.addr_ip6);
-	icmpv6_pack_hdr_na_mac(pkt + ETH_HDR_LEN + IP6_HDR_LEN, advertisementIpTarget.addr_ip6, advertisementLinkTarget.addr_eth);
+	ip6_pack_hdr(pkt + ETH_HDR_LEN, 0, 0, ICMPV6_ND_PAYLOAD_LEN, IP_PROTO_ICMPV6, IP6_HLIM_MAX, ipLayerSource.addr_ip6, ipLayerDestination.addr_ip6);
+
+	if (icmpv6MessageType == ICMPV6_NEIGHBOR_ADVERTISEMENT) {
+		icmpv6_pack_hdr_na_mac(pkt + ETH_HDR_LEN + IP6_HDR_LEN, ipLayerTarget.addr_ip6, linkLayerTarget.addr_eth);
+	} else if (icmpv6MessageType == ICMPV6_NEIGHBOR_SOLICITATION) {
+		icmpv6_pack_hdr_ns_mac(pkt + ETH_HDR_LEN + IP6_HDR_LEN, ipLayerTarget.addr_ip6, linkLayerTarget.addr_eth);
+	} else {
+		syslog(LOG_ERR, "ndp_send called with unknown neighbor solicitation message type %d", icmpv6MessageType);
+		return;
+	}
 
 	ip6_checksum(pkt + ETH_HDR_LEN, packetLength - ETH_HDR_LEN);
 
-	syslog(LOG_INFO, "ndp reply %s is-at %s", addr_ntoa(&advertisementIpTarget), addr_ntoa(&advertisementLinkTarget));
+	syslog(LOG_INFO, "ndp reply %s is-at %s", addr_ntoa(&ipLayerTarget), addr_ntoa(&linkLayerTarget));
 
 	if (eth_send(eth, pkt, sizeof(pkt)) != sizeof(pkt))
 		syslog(LOG_ERR, "couldn't send packet: %m");
@@ -186,9 +229,7 @@ ndp_recv_cb(struct tuple *summary, const struct icmpv6_msg_nd *query)
 	else
 		linkLayerSource = tmpl->ethernet_addr;
 
-	printf("Creating reply now\n");
-
-	ndp_send_advertisement(summary->inter->if_eth,
+	ndp_send(summary->inter->if_eth, ICMPV6_NEIGHBOR_ADVERTISEMENT,
 			*linkLayerSource, summary->linkLayer_src,
 			queryIP, summary->address_src,
 			*linkLayerSource, queryIP);

ndp.h

@@ -40,6 +40,7 @@ struct ndp_req {
 
 	struct interface	*inter;
 
+	// TODO: Document this
 	int			cnt;
 
 	struct event		active;
@@ -67,11 +68,17 @@ struct ndp_req *ndp_new(struct interface *inter,
     struct addr *pa, struct addr *ha);
 
 
-void ndp_send_advertisement(eth_t *eth,
+void ndp_send(eth_t *eth, uint icmpv6MessageType,
     struct addr linkLayerSource, struct addr linkLayerDestination,
     struct addr ipLayerSource, struct addr ipLayerDestination,
     struct addr advertisementLinkTarget, struct addr advertisementIpTarget);
 
+void ndp_request(struct interface *,
+    struct addr *src_pa, struct addr *src_ha,
+    struct addr *dst, void (*)(struct ndp_req *, int, void *), void *);
+
+struct ndp_req *ndp_find(struct addr *);
+
 struct ndp_req * ndp_find(struct addr *addr);
 void ndp_recv_cb(struct tuple *summary, const struct icmpv6_msg_nd *query);