Some additional checks will be needed in case of extension headers like the fragmentation or hop-by-hop (for jumbo frames for example) headers or ipsec stuff. But this patch should do for most people for now, the rest can be added with a later one.
Signed-off-by: Marek Lindner lindner_marek@yahoo.de Acked-by: Linus Lüssing linus.luessing@web.de --- batman-adv/gateway_client.c | 40 +++++++++++++++++++++++++++++++--------- 1 files changed, 31 insertions(+), 9 deletions(-)
diff --git a/batman-adv/gateway_client.c b/batman-adv/gateway_client.c index fde1d8a..0065ffb 100644 --- a/batman-adv/gateway_client.c +++ b/batman-adv/gateway_client.c @@ -24,6 +24,7 @@ #include "gateway_common.h" #include "hard-interface.h" #include <linux/ip.h> +#include <linux/ipv6.h> #include <linux/udp.h> #include <linux/if_vlan.h>
@@ -403,6 +404,7 @@ int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb) { struct ethhdr *ethhdr; struct iphdr *iphdr; + struct ipv6hdr *ipv6hdr; struct udphdr *udphdr; unsigned int header_len = 0;
@@ -424,17 +426,32 @@ int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb) }
/* check for ip header */ - if (ntohs(ethhdr->h_proto) != ETH_P_IP) - return 0; + switch (ntohs(ethhdr->h_proto)) { + case ETH_P_IP: + if (!pskb_may_pull(skb, header_len + sizeof(struct iphdr))) + return 0; + iphdr = (struct iphdr *)(skb->data + header_len); + header_len += iphdr->ihl * 4;
- if (!pskb_may_pull(skb, header_len + sizeof(struct iphdr))) - return 0; - iphdr = (struct iphdr *)(skb->data + header_len); - header_len += iphdr->ihl * 4; + /* check for udp header */ + if (iphdr->protocol != IPPROTO_UDP) + return 0; + + break; + case ETH_P_IPV6: + if (!pskb_may_pull(skb, header_len + sizeof(struct ipv6hdr))) + return 0; + ipv6hdr = (struct ipv6hdr *)(skb->data + header_len); + header_len += sizeof(struct ipv6hdr);
- /* check for udp header */ - if (iphdr->protocol != IPPROTO_UDP) + /* check for udp header */ + if (ipv6hdr->nexthdr != IPPROTO_UDP) + return 0; + + break; + default: return 0; + }
if (!pskb_may_pull(skb, header_len + sizeof(struct udphdr))) return 0; @@ -442,7 +459,12 @@ int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb) header_len += sizeof(struct udphdr);
/* check for bootp port */ - if (ntohs(udphdr->dest) != 67) + if ((ntohs(ethhdr->h_proto) == ETH_P_IP) && + (ntohs(udphdr->dest) != 67)) + return 0; + + if ((ntohs(ethhdr->h_proto) == ETH_P_IPV6) && + (ntohs(udphdr->dest) != 547)) return 0;
if (atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER)