From 60943122f7b3a5896ce64c9000e119931484c12c Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@tinc-vpn.org>
Date: Mon, 6 Oct 2003 13:49:57 +0000
Subject: [PATCH] Copy structs from packets to the stack before using them, to
prevent alignment issues.
---
src/route.c | 309 +++++++++++++++++++++++++++++-----------------------
1 file changed, 175 insertions(+), 134 deletions(-)
diff --git a/src/route.c b/src/route.c
index e9e07f67..d38b08e4 100644
--- a/src/route.c
+++ b/src/route.c
@@ -17,7 +17,7 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- $Id: route.c,v 1.1.2.66 2003/10/01 09:14:01 guus Exp $
+ $Id: route.c,v 1.1.2.67 2003/10/06 13:49:57 guus Exp $
*/
#include "system.h"
@@ -57,6 +57,17 @@ int macexpire = 600;
bool overwrite_mac = false;
mac_t mymac = {{0xFE, 0xFD, 0, 0, 0, 0}};
+/* Sizes of various headers */
+
+static size_t ether_size = sizeof(struct ether_header);
+static size_t arp_size = sizeof(struct ether_arp);
+static size_t ip_size = sizeof(struct ip);
+static size_t icmp_size = sizeof(struct icmp) - sizeof(struct ip);
+static size_t ip6_size = sizeof(struct ip6_hdr);
+static size_t icmp6_size = sizeof(struct icmp6_hdr);
+static size_t ns_size = sizeof(struct nd_neighbor_solicit);
+static size_t opt_size = sizeof(struct nd_opt_hdr);
+
/* RFC 1071 */
static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
@@ -78,13 +89,18 @@ static uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
return ~checksum;
}
-static bool ratelimit(void) {
+static bool ratelimit(int frequency) {
static time_t lasttime = 0;
+ static int count = 0;
- if(lasttime == now)
- return true;
+ if(lasttime == now) {
+ if(++count > frequency)
+ return true;
+ } else {
+ lasttime = now;
+ count = 0;
+ }
- lasttime = now;
return false;
}
@@ -174,59 +190,68 @@ static node_t *route_mac(vpn_packet_t *packet)
static void route_ipv4_unreachable(vpn_packet_t *packet, uint8_t code)
{
- struct ip *hdr;
- struct icmp *icmp;
+ struct ip ip;
+ struct icmp icmp;
struct in_addr ip_src;
struct in_addr ip_dst;
uint32_t oldlen;
- if(ratelimit())
+ if(ratelimit(3))
return;
cp();
- hdr = (struct ip *)(packet->data + 14);
- icmp = (struct icmp *)(packet->data + 14 + 20);
+ /* Copy headers from packet into properly aligned structs on the stack */
+
+ memcpy(&ip, packet->data + ether_size, ip_size);
+ memcpy(&icmp, packet->data + ether_size + ip_size, icmp_size);
/* Remember original source and destination */
- memcpy(&ip_src, &hdr->ip_src, 4);
- memcpy(&ip_dst, &hdr->ip_dst, 4);
- oldlen = packet->len - 14;
+ memcpy(&ip_src, &ip.ip_src, sizeof(ip_src));
+ memcpy(&ip_dst, &ip.ip_dst, sizeof(ip_dst));
+
+ oldlen = packet->len - ether_size;
- if(oldlen >= IP_MSS - sizeof(*hdr) - sizeof(*icmp))
- oldlen = IP_MSS - sizeof(*hdr) - sizeof(*icmp);
+ if(oldlen >= IP_MSS - ip_size - icmp_size)
+ oldlen = IP_MSS - ip_size - icmp_size;
/* Copy first part of original contents to ICMP message */
- memmove(&icmp->icmp_ip, hdr, oldlen);
+ memmove(packet->data + ether_size + ip_size + icmp_size, packet->data + ether_size, oldlen);
/* Fill in IPv4 header */
- hdr->ip_v = 4;
- hdr->ip_hl = sizeof(*hdr) / 4;
- hdr->ip_tos = 0;
- hdr->ip_len = htons(20 + 8 + oldlen);
- hdr->ip_id = 0;
- hdr->ip_off = 0;
- hdr->ip_ttl = 255;
- hdr->ip_p = IPPROTO_ICMP;
- hdr->ip_sum = 0;
- memcpy(&hdr->ip_src, &ip_dst, 4);
- memcpy(&hdr->ip_dst, &ip_src, 4);
-
- hdr->ip_sum = inet_checksum(hdr, 20, ~0);
+ ip.ip_v = 4;
+ ip.ip_hl = ip_size / 4;
+ ip.ip_tos = 0;
+ ip.ip_len = htons(ip_size + icmp_size + oldlen);
+ ip.ip_id = 0;
+ ip.ip_off = 0;
+ ip.ip_ttl = 255;
+ ip.ip_p = IPPROTO_ICMP;
+ ip.ip_sum = 0;
+ memcpy(&ip.ip_src, &ip_dst, sizeof(ip_src));
+ memcpy(&ip.ip_dst, &ip_src, sizeof(ip_dst));
+
+ ip.ip_sum = inet_checksum(&ip, ip_size, ~0);
/* Fill in ICMP header */
- icmp->icmp_type = ICMP_DEST_UNREACH;
- icmp->icmp_code = code;
- icmp->icmp_cksum = 0;
+ icmp.icmp_type = ICMP_DEST_UNREACH;
+ icmp.icmp_code = code;
+ icmp.icmp_cksum = 0;
- icmp->icmp_cksum = inet_checksum(icmp, 8 + oldlen, ~0);
+ icmp.icmp_cksum = inet_checksum(&icmp, icmp_size, ~0);
+ icmp.icmp_cksum = inet_checksum(packet->data + ether_size + ip_size + icmp_size, oldlen, icmp.icmp_cksum);
+
+ /* Copy structs on stack back to packet */
+
+ memcpy(packet->data + ether_size, &ip, ip_size);
+ memcpy(packet->data + ether_size + ip_size, &icmp, icmp_size);
- packet->len = 14 + 20 + 8 + oldlen;
+ packet->len = ether_size + ip_size + icmp_size + oldlen;
write_packet(packet);
}
@@ -261,8 +286,8 @@ static node_t *route_ipv4(vpn_packet_t *packet)
static void route_ipv6_unreachable(vpn_packet_t *packet, uint8_t code)
{
- struct ip6_hdr *hdr;
- struct icmp6_hdr *icmp;
+ struct ip6_hdr ip6;
+ struct icmp6_hdr icmp6;
uint16_t checksum;
struct {
@@ -272,55 +297,64 @@ static void route_ipv6_unreachable(vpn_packet_t *packet, uint8_t code)
uint32_t next;
} pseudo;
- if(ratelimit())
+ if(ratelimit(3))
return;
cp();
- hdr = (struct ip6_hdr *)(packet->data + 14);
- icmp = (struct icmp6_hdr *)(packet->data + 14 + sizeof(*hdr));
+ /* Copy headers from packet to structs on the stack */
+
+ memcpy(&ip6, packet->data + ether_size, ip6_size);
+ memcpy(&icmp6, packet->data + ether_size + ip6_size, icmp6_size);
/* Remember original source and destination */
- memcpy(&pseudo.ip6_src, &hdr->ip6_dst, 16);
- memcpy(&pseudo.ip6_dst, &hdr->ip6_src, 16);
- pseudo.length = ntohs(hdr->ip6_plen) + sizeof(*hdr);
+ memcpy(&pseudo.ip6_src, &ip6.ip6_dst, sizeof(ip6.ip6_src));
+ memcpy(&pseudo.ip6_dst, &ip6.ip6_src, sizeof(ip6.ip6_dst));
+
+ pseudo.length = ntohs(ip6.ip6_plen) + ip6_size;
- if(pseudo.length >= IP_MSS - sizeof(*hdr) - sizeof(*icmp))
- pseudo.length = IP_MSS - sizeof(*hdr) - sizeof(*icmp);
+ if(pseudo.length >= IP_MSS - ip6_size - icmp6_size)
+ pseudo.length = IP_MSS - ip6_size - icmp6_size;
/* Copy first part of original contents to ICMP message */
- memmove(((char *)icmp) + sizeof(*icmp), hdr, pseudo.length);
+ memmove(packet->data + ether_size + ip6_size + icmp6_size, packet->data + ether_size, pseudo.length);
/* Fill in IPv6 header */
- hdr->ip6_flow = htonl(0x60000000UL);
- hdr->ip6_plen = htons(sizeof(*icmp) + pseudo.length);
- hdr->ip6_nxt = IPPROTO_ICMPV6;
- hdr->ip6_hlim = 255;
- memcpy(&hdr->ip6_dst, &pseudo.ip6_dst, 16);
- memcpy(&hdr->ip6_src, &pseudo.ip6_src, 16);
+ ip6.ip6_flow = htonl(0x60000000UL);
+ ip6.ip6_plen = htons(icmp6_size + pseudo.length);
+ ip6.ip6_nxt = IPPROTO_ICMPV6;
+ ip6.ip6_hlim = 255;
+ memcpy(&ip6.ip6_src, &pseudo.ip6_src, sizeof(ip6.ip6_src));
+ memcpy(&ip6.ip6_dst, &pseudo.ip6_dst, sizeof(ip6.ip6_dst));
/* Fill in ICMP header */
- icmp->icmp6_type = ICMP6_DST_UNREACH;
- icmp->icmp6_code = code;
- icmp->icmp6_cksum = 0;
+ icmp6.icmp6_type = ICMP6_DST_UNREACH;
+ icmp6.icmp6_code = code;
+ icmp6.icmp6_cksum = 0;
/* Create pseudo header */
- pseudo.length = htonl(sizeof(*icmp) + pseudo.length);
+ pseudo.length = htonl(icmp6_size + pseudo.length);
pseudo.next = htonl(IPPROTO_ICMPV6);
/* Generate checksum */
checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
- checksum = inet_checksum(icmp, ntohl(pseudo.length), checksum);
+ checksum = inet_checksum(&icmp6, icmp6_size, checksum);
+ checksum = inet_checksum(packet->data + ether_size + ip6_size + icmp6_size, ntohl(pseudo.length) - icmp6_size, checksum);
- icmp->icmp6_cksum = checksum;
+ icmp6.icmp6_cksum = checksum;
+
+ /* Copy structs on stack back to packet */
+
+ memcpy(packet->data + ether_size, &ip6, ip6_size);
+ memcpy(packet->data + ether_size + ip6_size, &icmp6, icmp6_size);
- packet->len = 14 + sizeof(*hdr) + ntohl(pseudo.length);
+ packet->len = ether_size + ip6_size + ntohl(pseudo.length);
write_packet(packet);
}
@@ -358,9 +392,9 @@ static node_t *route_ipv6(vpn_packet_t *packet)
static void route_neighborsol(vpn_packet_t *packet)
{
- struct ip6_hdr *hdr;
- struct nd_neighbor_solicit *ns;
- struct nd_opt_hdr *opt;
+ struct ip6_hdr ip6;
+ struct nd_neighbor_solicit ns;
+ struct nd_opt_hdr opt;
subnet_t *subnet;
uint16_t checksum;
@@ -373,34 +407,37 @@ static void route_neighborsol(vpn_packet_t *packet)
cp();
- hdr = (struct ip6_hdr *)(packet->data + 14);
- ns = (struct nd_neighbor_solicit *)(packet->data + 14 + sizeof(*hdr));
- opt = (struct nd_opt_hdr *)(packet->data + 14 + sizeof(*hdr) + sizeof(*ns));
+ /* Copy headers from packet to structs on the stack */
+
+ memcpy(&ip6, packet->data + ether_size, ip6_size);
+ memcpy(&ns, packet->data + ether_size + ip6_size, ns_size);
+ memcpy(&opt, packet->data + ether_size + ip6_size + ns_size, opt_size);
/* First, snatch the source address from the neighbor solicitation packet */
if(overwrite_mac)
- memcpy(mymac.x, packet->data + 6, 6);
+ memcpy(mymac.x, packet->data + ETH_ALEN, ETH_ALEN);
/* Check if this is a valid neighbor solicitation request */
- if(ns->nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
- opt->nd_opt_type != ND_OPT_SOURCE_LINKADDR) {
+ if(ns.nd_ns_hdr.icmp6_type != ND_NEIGHBOR_SOLICIT ||
+ opt.nd_opt_type != ND_OPT_SOURCE_LINKADDR) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: received unknown type neighbor solicitation request"));
return;
}
/* Create pseudo header */
- memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
- memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
- pseudo.length = htonl(sizeof(*ns) + sizeof(*opt) + 6);
+ memcpy(&pseudo.ip6_src, &ip6.ip6_src, sizeof(ip6.ip6_src));
+ memcpy(&pseudo.ip6_dst, &ip6.ip6_dst, sizeof(ip6.ip6_dst));
+ pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
pseudo.next = htonl(IPPROTO_ICMPV6);
/* Generate checksum */
checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
- checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
+ checksum = inet_checksum(&ns, ns_size, checksum);
+ checksum = inet_checksum(&opt, opt_size, checksum);
if(checksum) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: checksum error for neighbor solicitation request"));
@@ -409,18 +446,18 @@ static void route_neighborsol(vpn_packet_t *packet)
/* Check if the IPv6 address exists on the VPN */
- subnet = lookup_subnet_ipv6((ipv6_t *) &ns->nd_ns_target);
+ subnet = lookup_subnet_ipv6((ipv6_t *) &ns.nd_ns_target);
if(!subnet) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: neighbor solicitation request for unknown address %hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx"),
- ntohs(((uint16_t *) &ns->nd_ns_target)[0]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[1]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[2]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[3]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[4]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[5]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[6]),
- ntohs(((uint16_t *) &ns->nd_ns_target)[7]));
+ ntohs(((uint16_t *) &ns.nd_ns_target)[0]),
+ ntohs(((uint16_t *) &ns.nd_ns_target)[1]),
+ ntohs(((uint16_t *) &ns.nd_ns_target)[2]),
+ ntohs(((uint16_t *) &ns.nd_ns_target)[3]),
+ ntohs(((uint16_t *) &ns.nd_ns_target)[4]),
+ ntohs(((uint16_t *) &ns.nd_ns_target)[5]),
+ ntohs(((uint16_t *) &ns.nd_ns_target)[6]),
+ ntohs(((uint16_t *) &ns.nd_ns_target)[7]));
return;
}
@@ -432,35 +469,39 @@ static void route_neighborsol(vpn_packet_t *packet)
/* Create neighbor advertation reply */
- memcpy(packet->data, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* copy destination address */
- packet->data[ETHER_ADDR_LEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
+ memcpy(packet->data, packet->data + ETH_ALEN, ETH_ALEN); /* copy destination address */
+ packet->data[ETH_ALEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
- memcpy(&hdr->ip6_dst, &hdr->ip6_src, 16); /* swap destination and source protocol address */
- memcpy(&hdr->ip6_src, &ns->nd_ns_target, 16); /* ... */
+ memcpy(&ip6.ip6_src, &ns.nd_ns_target, sizeof(ip6.ip6_src)); /* swap destination and source protocol address */
+ memcpy(&ip6.ip6_dst, &ip6.ip6_src, sizeof(ip6.ip6_dst)); /* ... */
- memcpy((char *) opt + sizeof(*opt), packet->data + ETHER_ADDR_LEN, 6); /* add fake source hard addr */
+ memcpy(&opt + opt_size, packet->data + ETH_ALEN, ETH_ALEN); /* add fake source hard addr */
- ns->nd_ns_hdr.icmp6_cksum = 0;
- ns->nd_ns_hdr.icmp6_type = ND_NEIGHBOR_ADVERT;
- ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[0] = 0x40; /* Set solicited flag */
- ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[1] =
- ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[2] =
- ns->nd_ns_hdr.icmp6_dataun.icmp6_un_data8[3] = 0;
- opt->nd_opt_type = ND_OPT_TARGET_LINKADDR;
+ ns.nd_ns_cksum = 0;
+ ns.nd_ns_type = ND_NEIGHBOR_ADVERT;
+ ns.nd_ns_reserved = htonl(0x40000000UL); /* Set solicited flag */
+ opt.nd_opt_type = ND_OPT_TARGET_LINKADDR;
/* Create pseudo header */
- memcpy(&pseudo.ip6_src, &hdr->ip6_src, 16);
- memcpy(&pseudo.ip6_dst, &hdr->ip6_dst, 16);
- pseudo.length = htonl(sizeof(*ns) + sizeof(*opt) + 6);
+ memcpy(&pseudo.ip6_src, &ip6.ip6_src, sizeof(ip6.ip6_src));
+ memcpy(&pseudo.ip6_dst, &ip6.ip6_dst, sizeof(ip6.ip6_dst));
+ pseudo.length = htonl(ns_size + opt_size + ETH_ALEN);
pseudo.next = htonl(IPPROTO_ICMPV6);
/* Generate checksum */
checksum = inet_checksum(&pseudo, sizeof(pseudo), ~0);
- checksum = inet_checksum(ns, sizeof(*ns) + 8, checksum);
+ checksum = inet_checksum(&ns, ns_size, checksum);
+ checksum = inet_checksum(&opt, opt_size, checksum);
+
+ ns.nd_ns_hdr.icmp6_cksum = checksum;
- ns->nd_ns_hdr.icmp6_cksum = checksum;
+ /* Copy structs on stack back to packet */
+
+ memcpy(packet->data + ether_size, &ip6, ip6_size);
+ memcpy(packet->data + ether_size + ip6_size, &ns, ns_size);
+ memcpy(packet->data + ether_size + ip6_size + ns_size, &opt, opt_size);
write_packet(packet);
}
@@ -469,40 +510,37 @@ static void route_neighborsol(vpn_packet_t *packet)
static void route_arp(vpn_packet_t *packet)
{
- struct ether_arp *arp;
+ struct ether_arp arp;
subnet_t *subnet;
- uint8_t ipbuf[4];
+ struct in_addr addr;
cp();
/* First, snatch the source address from the ARP packet */
if(overwrite_mac)
- memcpy(mymac.x, packet->data + 6, 6);
+ memcpy(mymac.x, packet->data + ETH_ALEN, ETH_ALEN);
- /* This routine generates replies to ARP requests.
- You don't need to set NOARP flag on the interface anymore (which is broken on FreeBSD).
- Most of the code here is taken from choparp.c by Takamichi Tateoka (tree@mma.club.uec.ac.jp)
- */
+ /* Copy headers from packet to structs on the stack */
- arp = (struct ether_arp *)(packet->data + 14);
+ memcpy(&arp, packet->data + ether_size, arp_size);
/* Check if this is a valid ARP request */
- if(ntohs(arp->arp_hrd) != ARPHRD_ETHER || ntohs(arp->arp_pro) != ETHERTYPE_IP ||
- arp->arp_hln != ETHER_ADDR_LEN || arp->arp_pln != 4 || ntohs(arp->arp_op) != ARPOP_REQUEST) {
+ if(ntohs(arp.arp_hrd) != ARPHRD_ETHER || ntohs(arp.arp_pro) != ETH_P_IP ||
+ arp.arp_hln != ETH_ALEN || arp.arp_pln != sizeof(addr) || ntohs(arp.arp_op) != ARPOP_REQUEST) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: received unknown type ARP request"));
return;
}
/* Check if the IPv4 address exists on the VPN */
- subnet = lookup_subnet_ipv4((ipv4_t *) arp->arp_tpa);
+ subnet = lookup_subnet_ipv4((ipv4_t *) &arp.arp_tpa);
if(!subnet) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Cannot route packet: ARP request for unknown address %d.%d.%d.%d"),
- arp->arp_tpa[0], arp->arp_tpa[1], arp->arp_tpa[2],
- arp->arp_tpa[3]);
+ arp.arp_tpa[0], arp.arp_tpa[1], arp.arp_tpa[2],
+ arp.arp_tpa[3]);
return;
}
@@ -511,16 +549,20 @@ static void route_arp(vpn_packet_t *packet)
if(subnet->owner == myself)
return; /* silently ignore */
- memcpy(packet->data, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* copy destination address */
- packet->data[ETHER_ADDR_LEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
+ memcpy(packet->data, packet->data + ETH_ALEN, ETH_ALEN); /* copy destination address */
+ packet->data[ETH_ALEN * 2 - 1] ^= 0xFF; /* mangle source address so it looks like it's not from us */
+
+ memcpy(&addr, arp.arp_tpa, sizeof(addr)); /* save protocol addr */
+ memcpy(arp.arp_tpa, arp.arp_spa, sizeof(addr)); /* swap destination and source protocol address */
+ memcpy(arp.arp_spa, &addr, sizeof(addr)); /* ... */
- memcpy(ipbuf, arp->arp_tpa, 4); /* save protocol addr */
- memcpy(arp->arp_tpa, arp->arp_spa, 4); /* swap destination and source protocol address */
- memcpy(arp->arp_spa, ipbuf, 4); /* ... */
+ memcpy(arp.arp_tha, arp.arp_sha, ETH_ALEN); /* set target hard/proto addr */
+ memcpy(arp.arp_sha, packet->data + ETH_ALEN, ETH_ALEN); /* add fake source hard addr */
+ arp.arp_op = htons(ARPOP_REPLY);
- memcpy(arp->arp_tha, arp->arp_sha, 10); /* set target hard/proto addr */
- memcpy(arp->arp_sha, packet->data + ETHER_ADDR_LEN, ETHER_ADDR_LEN); /* add fake source hard addr */
- arp->arp_op = htons(ARPOP_REPLY);
+ /* Copy structs on stack back to packet */
+
+ memcpy(packet->data + ether_size, &arp, arp_size);
write_packet(packet);
}
@@ -532,7 +574,7 @@ void route_outgoing(vpn_packet_t *packet)
cp();
- if(packet->len < 14) {
+ if(packet->len < ether_size) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
return;
}
@@ -543,8 +585,8 @@ void route_outgoing(vpn_packet_t *packet)
case RMODE_ROUTER:
type = ntohs(*((uint16_t *)(&packet->data[12])));
switch (type) {
- case 0x0800:
- if(packet->len < 34) {
+ case ETH_P_IP:
+ if(packet->len < ether_size + ip_size) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
return;
}
@@ -552,21 +594,21 @@ void route_outgoing(vpn_packet_t *packet)
n = route_ipv4(packet);
break;
- case 0x86DD:
- if(packet->len < 54) {
+ case ETH_P_IPV6:
+ if(packet->len < ether_size + ip6_size) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
return;
}
- if(packet->data[20] == IPPROTO_ICMPV6 && packet->len >= 62 && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
+ if(packet->data[20] == IPPROTO_ICMPV6 && packet->len >= ether_size + ip6_size + ns_size && packet->data[54] == ND_NEIGHBOR_SOLICIT) {
route_neighborsol(packet);
return;
}
n = route_ipv6(packet);
break;
- case 0x0806:
- if(packet->len < 42) {
+ case ETH_P_ARP:
+ if(packet->len < ether_size + arp_size) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
return;
}
@@ -598,9 +640,8 @@ void route_outgoing(vpn_packet_t *packet)
void route_incoming(node_t *source, vpn_packet_t *packet)
{
- if(packet->len < 14) {
- ifdebug(TRAFFIC) logger(LOG_WARNING, _("Got too short packet from %s (%s)"),
- source->name, source->hostname);
+ if(packet->len < ether_size) {
+ ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
return;
}
@@ -612,8 +653,8 @@ void route_incoming(node_t *source, vpn_packet_t *packet)
type = ntohs(*((uint16_t *)(&packet->data[12])));
switch (type) {
- case 0x0800:
- if(packet->len < 34) {
+ case ETH_P_IP:
+ if(packet->len < ether_size + ip_size) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
return;
}
@@ -621,8 +662,8 @@ void route_incoming(node_t *source, vpn_packet_t *packet)
n = route_ipv4(packet);
break;
- case 0x86DD:
- if(packet->len < 54) {
+ case ETH_P_IPV6:
+ if(packet->len < ether_size + ip6_size) {
ifdebug(TRAFFIC) logger(LOG_WARNING, _("Read too short packet"));
return;
}
@@ -638,7 +679,7 @@ void route_incoming(node_t *source, vpn_packet_t *packet)
if(n) {
if(n == myself) {
if(overwrite_mac)
- memcpy(packet->data, mymac.x, 6);
+ memcpy(packet->data, mymac.x, ETH_ALEN);
write_packet(packet);
} else
send_packet(n, packet);
--
2.39.5