From: fendo <fendo@bi12info.com>
Date: Thu, 18 Sep 2014 16:16:21 +0000 (+0200)
Subject: new feature: If the user attribute "Framed-IPv6-Address" is defined then the ICMPv6_R... 
X-Git-Tag: 2.2.1-2fdn3.15~1
X-Git-Url: http://git.sameswireless.fr/l2tpns.git/commitdiff_plain/8d94f2020d372385156e9618d6279ba964ba8870?ds=inline

new feature: If the user attribute "Framed-IPv6-Address" is defined then the ICMPv6_RA advertise this IPv6 address.
Fix: Incorrect delegation of IPv6 prefixes when multiple of 4 bits (nibble) (eg: /44, /52 ...).
---

diff --git a/icmp.c b/icmp.c
index 0d6c65e..d2f53e0 100644
--- a/icmp.c
+++ b/icmp.c
@@ -143,7 +143,13 @@ void send_ipv6_ra(sessionidt s, tunnelidt t, struct in6_addr *ip)
 	pinfo->nd_opt_pi_preferred_time = htonl(604800);
 	pinfo->nd_opt_pi_reserved2      = 0;
 	pinfo->nd_opt_pi_prefix_len     = 64; // prefix length
-	pinfo->nd_opt_pi_prefix         = config->ipv6_prefix;
+	if (session[s].ipv6address.s6_addr[0])
+	{
+		// MSB 64bits of assigned IPv6 address to user (see radius attribut Framed-IPv6-Address)
+		memcpy(&pinfo->nd_opt_pi_prefix, &session[s].ipv6address.s6_addr[0], 8);
+	}
+	else
+		pinfo->nd_opt_pi_prefix     = config->ipv6_prefix;
 
 	// // Length of payload (not header)
 	p_ip6_hdr->ip6_plen = htons(sizeof(*pinfo) + sizeof(*p_nra));
diff --git a/l2tpns.c b/l2tpns.c
index cc69c2d..dd1e8ae 100644
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -102,7 +102,7 @@ union iphash {
 struct ipv6radix {
 	sessionidt sess;
 	struct ipv6radix *branch;
-} ipv6_hash[256];		// Mapping from IPv6 address to session structures.
+} ipv6_hash[16];		// Mapping from IPv6 address to session structures.
 
 // Traffic counters.
 static uint32_t udp_rx = 0, udp_rx_pkt = 0, udp_tx = 0;
@@ -983,19 +983,24 @@ static sessionidt lookup_ipv6map(struct in6_addr ip)
 	char ipv6addr[INET6_ADDRSTRLEN];
 
 	curnode = &ipv6_hash[ip.s6_addr[0]];
+	curnode = &ipv6_hash[((ip.s6_addr[0]) & 0xF0)>>4];
 	i = 1;
 	s = curnode->sess;
 
-	while (s == 0 && i < 15 && curnode->branch != NULL)
+	while (s == 0 && i < 32 && curnode->branch != NULL)
 	{
-		curnode = &curnode->branch[ip.s6_addr[i]];
+		if (i & 1)
+			curnode = &curnode->branch[ip.s6_addr[i>>1] & 0x0F];
+		else
+			curnode = &curnode->branch[(ip.s6_addr[i>>1] & 0xF0)>>4];
+
 		s = curnode->sess;
 		i++;
 	}
 
 	LOG(4, s, session[s].tunnel, "Looking up address %s and got %d\n",
-    			inet_ntop(AF_INET6, &ip, ipv6addr,
-				INET6_ADDRSTRLEN),
+			inet_ntop(AF_INET6, &ip, ipv6addr,
+			INET6_ADDRSTRLEN),
 			s);
 
 	return s;
@@ -1036,6 +1041,19 @@ sessionidt sessionbyipv6(struct in6_addr ip)
 	return 0;
 }
 
+sessionidt sessionbyipv6new(struct in6_addr ip)
+{
+	sessionidt s;
+	CSTAT(sessionbyipv6new);
+
+	s = lookup_ipv6map(ip);
+
+	if (s > 0 && s < MAXSESSION && session[s].opened)
+		return s;
+
+	return 0;
+}
+
 //
 // Take an IP address in HOST byte order and
 // add it to the sessionid by IP cache.
@@ -1075,22 +1093,28 @@ static void uncache_ipmap(in_addr_t ip)
 static void cache_ipv6map(struct in6_addr ip, int prefixlen, sessionidt s)
 {
 	int i;
-	int bytes;
+	int niblles;
 	struct ipv6radix *curnode;
 	char ipv6addr[INET6_ADDRSTRLEN];
 
-	curnode = &ipv6_hash[ip.s6_addr[0]];
+	curnode = &ipv6_hash[((ip.s6_addr[0]) & 0xF0)>>4];
 
-	bytes = prefixlen >> 3;
+	niblles = prefixlen >> 2;
 	i = 1;
-	while (i < bytes) {
+
+	while (i < niblles)
+	{
 		if (curnode->branch == NULL)
 		{
-			if (!(curnode->branch = calloc(256,
-					sizeof (struct ipv6radix))))
+			if (!(curnode->branch = calloc(16, sizeof (struct ipv6radix))))
 				return;
 		}
-		curnode = &curnode->branch[ip.s6_addr[i]];
+
+		if (i & 1)
+			curnode = &curnode->branch[ip.s6_addr[i>>1] & 0x0F];
+		else
+			curnode = &curnode->branch[(ip.s6_addr[i>>1] & 0xF0)>>4];
+
 		i++;
 	}
 
@@ -1098,13 +1122,13 @@ static void cache_ipv6map(struct in6_addr ip, int prefixlen, sessionidt s)
 
 	if (s > 0)
 		LOG(4, s, session[s].tunnel, "Caching ip address %s/%d\n",
-	    			inet_ntop(AF_INET6, &ip, ipv6addr, 
-					INET6_ADDRSTRLEN),
+				inet_ntop(AF_INET6, &ip, ipv6addr,
+				INET6_ADDRSTRLEN),
 				prefixlen);
 	else if (s == 0)
 		LOG(4, 0, 0, "Un-caching ip address %s/%d\n",
-	    			inet_ntop(AF_INET6, &ip, ipv6addr, 
-					INET6_ADDRSTRLEN),
+				inet_ntop(AF_INET6, &ip, ipv6addr,
+				INET6_ADDRSTRLEN),
 				prefixlen);
 }
 
@@ -1155,7 +1179,6 @@ int cmd_show_ipcache(struct cli_def *cli, const char *command, char **argv, int
 	return CLI_OK;
 }
 
-
 // Find session by username, 0 for not found
 // walled garden users aren't authenticated, so the username is
 // reasonably useless. Ignore them to avoid incorrect actions
@@ -1692,7 +1715,6 @@ static void processipv6out(uint8_t * buf, int len)
 	sessionidt s;
 	sessiont *sp;
 	tunnelidt t;
-	in_addr_t ip;
 	struct in6_addr ip6;
 
 	uint8_t *data = buf;	// Keep a copy of the originals.
@@ -1731,10 +1753,9 @@ static void processipv6out(uint8_t * buf, int len)
 
 	if (s == 0)
 	{
-		ip = *(uint32_t *)(buf + 32);
-		s = sessionbyip(ip);
+		s = sessionbyipv6new(ip6);
 	}
-	
+
 	if (s == 0)
 	{
 		// Is this a packet for a session that doesn't exist?
diff --git a/l2tpns.h b/l2tpns.h
index 80a8dbb..fdfaa62 100644
--- a/l2tpns.h
+++ b/l2tpns.h
@@ -606,6 +606,7 @@ struct Tstats
     uint32_t	call_processudp;
     uint32_t	call_sessionbyip;
     uint32_t	call_sessionbyipv6;
+    uint32_t	call_sessionbyipv6new;
     uint32_t	call_sessionbyuser;
     uint32_t	call_sendarp;
     uint32_t	call_sendipcp;
@@ -951,6 +952,7 @@ void send_ipv6_ra(sessionidt s, tunnelidt t, struct in6_addr *ip);
 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add);
 sessionidt sessionbyip(in_addr_t ip);
 sessionidt sessionbyipv6(struct in6_addr ip);
+sessionidt sessionbyipv6new(struct in6_addr ip);
 sessionidt sessionbyuser(char *username);
 void increment_counter(uint32_t *counter, uint32_t *wrap, uint32_t delta);
 void random_data(uint8_t *buf, int len);
diff --git a/ppp.c b/ppp.c
index 6bcb8f0..21f5985 100644
--- a/ppp.c
+++ b/ppp.c
@@ -1580,8 +1580,16 @@ void processipv6cp(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 				gotip++; // seen address
 				if (o[1] != 10) return;
 
-				ident[0] = htonl(session[s].ip);
-				ident[1] = 0;
+				if (session[s].ipv6address.s6_addr[0])
+				{
+					// LSB 64bits of assigned IPv6 address to user (see radius attribut Framed-IPv6-Address)
+					memcpy(&ident[0], &session[s].ipv6address.s6_addr[8], 8);
+				}
+				else
+				{
+					ident[0] = htonl(session[s].ip);
+					ident[1] = 0;
+				}
 
 				if (memcmp(o + 2, ident, sizeof(ident)))
 				{
@@ -2254,7 +2262,18 @@ void processipv6in(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l)
 		return;
 
 	// no spoof
-	if ((ipv4 != session[s].ip || memcmp(&config->ipv6_prefix, &ip, 8)) && sessionbyipv6(ip) != s)
+	if (session[s].ipv6address.s6_addr[0])
+	{
+		if ((sessionbyipv6new(ip) != s) &&
+			(ip.s6_addr[0] != 0xFE || ip.s6_addr[1] != 0x80 || ip.s6_addr16[1] != 0 || ip.s6_addr16[2] != 0 || ip.s6_addr16[3] != 0))
+		{
+			char str[INET6_ADDRSTRLEN];
+			LOG(5, s, t, "Dropping packet with spoofed IP %s\n",
+					inet_ntop(AF_INET6, &ip, str, INET6_ADDRSTRLEN));
+			return;
+		}
+	}
+	else if ((ipv4 != session[s].ip || memcmp(&config->ipv6_prefix, &ip, 8)) && sessionbyipv6(ip) != s)
 	{
 		char str[INET6_ADDRSTRLEN];
 		LOG(5, s, t, "Dropping packet with spoofed IP %s\n",