ipv6: implemented special handling of /128 prefixes

If prefix length is 128 then send RA with 64 prefix length and add point-to-point ipv6 address on interface

2 files changed, 40 insertions, 29 deletions

diff --git a/accel-pppd/ipv6/dhcpv6.c b/accel-pppd/ipv6/dhcpv6.c
index d99165c..2122f29 100644
--- a/accel-pppd/ipv6/dhcpv6.c
+++ b/accel-pppd/ipv6/dhcpv6.c
@@ -166,6 +166,9 @@ static void build_addr(struct ipv6db_addr_t *a, uint64_t intf_id, struct in6_add
 {
 	memcpy(addr, &a->addr, sizeof(*addr));
 
+	if (a->prefix_len == 128)
+		return;
+
 	if (a->prefix_len <= 64)
 		*(uint64_t *)(addr->s6_addr + 8) = intf_id;
 	else
@@ -310,10 +313,14 @@ static void dhcpv6_send_reply(struct dhcpv6_packet *req, struct dhcpv6_pd *pd, i
 					ia_addr->valid_lifetime = htonl(conf_valid_lifetime);
 
 					if (!a->installed) {
-						if (a->prefix_len > 64)
-							ip6route_add(ses->ifindex, &a->addr, a->prefix_len, 0);
-						else {
-							struct in6_addr addr;
+						struct in6_addr addr, peer_addr;
+						if (a->prefix_len == 128) {
+							memcpy(addr.s6_addr, &a->addr, 8);
+							memcpy(addr.s6_addr + 8, &ses->ipv6->intf_id, 8);
+							memcpy(peer_addr.s6_addr, &a->addr, 8);
+							memcpy(peer_addr.s6_addr + 8, &ses->ipv6->peer_intf_id, 8);
+							ip6addr_add_peer(ses->ifindex, &addr, &peer_addr);
+						} else {
 							memcpy(addr.s6_addr, &a->addr, 8);
 							memcpy(addr.s6_addr + 8, &ses->ipv6->intf_id, 8);
 							ip6addr_add(ses->ifindex, &addr, a->prefix_len);
diff --git a/accel-pppd/ipv6/nd.c b/accel-pppd/ipv6/nd.c
index f2a259a..231f180 100644
--- a/accel-pppd/ipv6/nd.c
+++ b/accel-pppd/ipv6/nd.c
@@ -94,8 +94,9 @@ static void *pd_key;
 #define BUF_SIZE 1024
 static mempool_t buf_pool;
 
-static void ipv6_nd_send_ra(struct ipv6_nd_handler_t *h, struct sockaddr_in6 *addr)
+static void ipv6_nd_send_ra(struct ipv6_nd_handler_t *h, struct sockaddr_in6 *dst_addr)
 {
+	struct ap_session *ses = h->ses;
 	void *buf = mempool_alloc(buf_pool), *endptr;
 	struct nd_router_advert *adv = buf;
 	struct nd_opt_prefix_info *pinfo;
@@ -105,14 +106,15 @@ static void ipv6_nd_send_ra(struct ipv6_nd_handler_t *h, struct sockaddr_in6 *ad
 	struct nd_opt_dnssl_info_local *dnsslinfo;
 	//struct nd_opt_mtu *mtu;
 	struct ipv6db_addr_t *a;
-	int i;
+	struct in6_addr addr, peer_addr;
+	int i, prefix_len;
 
 	if (!buf) {
 		log_emerg("out of memory\n");
 		return;
 	}
 
-	if (!h->ses->ipv6) {
+	if (!ses->ipv6) {
 		triton_timer_del(&h->timer);
 		return;
 	}
@@ -128,30 +130,32 @@ static void ipv6_nd_send_ra(struct ipv6_nd_handler_t *h, struct sockaddr_in6 *ad
 	adv->nd_ra_retransmit = htonl(conf_AdvRetransTimer);
 
 	pinfo = (struct nd_opt_prefix_info *)(adv + 1);
-	list_for_each_entry(a, &h->ses->ipv6->addr_list, entry) {
-		if (a->prefix_len < 128) {
-			memset(pinfo, 0, sizeof(*pinfo));
-			pinfo->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
-			pinfo->nd_opt_pi_len = 4;
-			pinfo->nd_opt_pi_prefix_len = a->prefix_len;
-			pinfo->nd_opt_pi_flags_reserved =
-				((a->flag_onlink || conf_AdvPrefixOnLinkFlag) ? ND_OPT_PI_FLAG_ONLINK : 0) |
-				((a->flag_auto || (conf_AdvPrefixAutonomousFlag && a->prefix_len == 64)) ? ND_OPT_PI_FLAG_AUTO : 0);
-			pinfo->nd_opt_pi_valid_time = htonl(conf_AdvPrefixValidLifetime);
-			pinfo->nd_opt_pi_preferred_time = htonl(conf_AdvPrefixPreferredLifetime);
-			memcpy(&pinfo->nd_opt_pi_prefix, &a->addr, (a->prefix_len + 7) / 8);
-			pinfo->nd_opt_pi_prefix.s6_addr[a->prefix_len / 8] &= ~(0xff >> (a->prefix_len % 8));
-			pinfo++;
-		}
+	list_for_each_entry(a, &ses->ipv6->addr_list, entry) {
+		prefix_len = a->prefix_len == 128 ? 64 : a->prefix_len;
+		memset(pinfo, 0, sizeof(*pinfo));
+		pinfo->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
+		pinfo->nd_opt_pi_len = 4;
+		pinfo->nd_opt_pi_prefix_len = prefix_len;
+		pinfo->nd_opt_pi_flags_reserved =
+			((a->flag_onlink || conf_AdvPrefixOnLinkFlag) ? ND_OPT_PI_FLAG_ONLINK : 0) |
+			((a->flag_auto || (conf_AdvPrefixAutonomousFlag && prefix_len == 64)) ? ND_OPT_PI_FLAG_AUTO : 0);
+		pinfo->nd_opt_pi_valid_time = htonl(conf_AdvPrefixValidLifetime);
+		pinfo->nd_opt_pi_preferred_time = htonl(conf_AdvPrefixPreferredLifetime);
+		memcpy(&pinfo->nd_opt_pi_prefix, &a->addr, (prefix_len + 7) / 8);
+		pinfo->nd_opt_pi_prefix.s6_addr[prefix_len / 8] &= ~(0xff >> (prefix_len % 8));
+		pinfo++;
 
 		if (!a->installed) {
-			if (a->prefix_len > 64)
-				ip6route_add(h->ses->ifindex, &a->addr, a->prefix_len, 0);
-			else {
-				struct in6_addr addr;
+			if (a->prefix_len == 128) {
+				memcpy(addr.s6_addr, &a->addr, 8);
+				memcpy(addr.s6_addr + 8, &ses->ipv6->intf_id, 8);
+				memcpy(peer_addr.s6_addr, &a->addr, 8);
+				memcpy(peer_addr.s6_addr + 8, &ses->ipv6->peer_intf_id, 8);
+				ip6addr_add_peer(ses->ifindex, &addr, &peer_addr);
+			} else {
 				memcpy(addr.s6_addr, &a->addr, 8);
-				memcpy(addr.s6_addr + 8, &h->ses->ipv6->intf_id, 8);
-				ip6addr_add(h->ses->ifindex, &addr, a->prefix_len);
+				memcpy(addr.s6_addr + 8, &ses->ipv6->intf_id, 8);
+				ip6addr_add(ses->ifindex, &addr, a->prefix_len);
 			}
 			a->installed = 1;
 		}
@@ -194,7 +198,7 @@ static void ipv6_nd_send_ra(struct ipv6_nd_handler_t *h, struct sockaddr_in6 *ad
 	} else
 		endptr = rdnss_addr;
 
-	net->sendto(h->hnd.fd, buf, endptr - buf, 0, (struct sockaddr *)addr, sizeof(*addr));
+	net->sendto(h->hnd.fd, buf, endptr - buf, 0, (struct sockaddr *)dst_addr, sizeof(*dst_addr));
 
 	mempool_free(buf);
 }