diff options
Diffstat (limited to 'net/bridge/netfilter/nf_tables_bridge.c')
| -rw-r--r-- | net/bridge/netfilter/nf_tables_bridge.c | 94 |
1 files changed, 91 insertions, 3 deletions
diff --git a/net/bridge/netfilter/nf_tables_bridge.c b/net/bridge/netfilter/nf_tables_bridge.c index da17a5e..19473a9 100644 --- a/net/bridge/netfilter/nf_tables_bridge.c +++ b/net/bridge/netfilter/nf_tables_bridge.c @@ -13,6 +13,82 @@ #include <linux/module.h> #include <linux/netfilter_bridge.h> #include <net/netfilter/nf_tables.h> +#include <net/netfilter/nf_tables_bridge.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <net/netfilter/nf_tables_ipv4.h> +#include <net/netfilter/nf_tables_ipv6.h> + +int nft_bridge_iphdr_validate(struct sk_buff *skb) +{ + struct iphdr *iph; + u32 len; + + if (!pskb_may_pull(skb, sizeof(struct iphdr))) + return 0; + + iph = ip_hdr(skb); + if (iph->ihl < 5 || iph->version != 4) + return 0; + + len = ntohs(iph->tot_len); + if (skb->len < len) + return 0; + else if (len < (iph->ihl*4)) + return 0; + + if (!pskb_may_pull(skb, iph->ihl*4)) + return 0; + + return 1; +} +EXPORT_SYMBOL_GPL(nft_bridge_iphdr_validate); + +int nft_bridge_ip6hdr_validate(struct sk_buff *skb) +{ + struct ipv6hdr *hdr; + u32 pkt_len; + + if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) + return 0; + + hdr = ipv6_hdr(skb); + if (hdr->version != 6) + return 0; + + pkt_len = ntohs(hdr->payload_len); + if (pkt_len + sizeof(struct ipv6hdr) > skb->len) + return 0; + + return 1; +} +EXPORT_SYMBOL_GPL(nft_bridge_ip6hdr_validate); + +static inline void nft_bridge_set_pktinfo_ipv4(struct nft_pktinfo *pkt, + const struct nf_hook_ops *ops, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out) +{ + if (nft_bridge_iphdr_validate(skb)) + nft_set_pktinfo_ipv4(pkt, ops, skb, in, out); + else + nft_set_pktinfo(pkt, ops, skb, in, out); +} + +static inline void nft_bridge_set_pktinfo_ipv6(struct nft_pktinfo *pkt, + const struct nf_hook_ops *ops, + struct sk_buff *skb, + const struct net_device *in, + const struct net_device *out) +{ +#if IS_ENABLED(CONFIG_IPV6) + if (nft_bridge_ip6hdr_validate(skb) && + nft_set_pktinfo_ipv6(pkt, ops, skb, in, out) == 0) + return; +#endif + nft_set_pktinfo(pkt, ops, skb, in, out); +} static unsigned int nft_do_chain_bridge(const struct nf_hook_ops *ops, @@ -23,7 +99,17 @@ nft_do_chain_bridge(const struct nf_hook_ops *ops, { struct nft_pktinfo pkt; - nft_set_pktinfo(&pkt, ops, skb, in, out); + switch (eth_hdr(skb)->h_proto) { + case htons(ETH_P_IP): + nft_bridge_set_pktinfo_ipv4(&pkt, ops, skb, in, out); + break; + case htons(ETH_P_IPV6): + nft_bridge_set_pktinfo_ipv6(&pkt, ops, skb, in, out); + break; + default: + nft_set_pktinfo(&pkt, ops, skb, in, out); + break; + } return nft_do_chain(&pkt, ops); } @@ -75,9 +161,11 @@ static const struct nf_chain_type filter_bridge = { .type = NFT_CHAIN_T_DEFAULT, .family = NFPROTO_BRIDGE, .owner = THIS_MODULE, - .hook_mask = (1 << NF_BR_LOCAL_IN) | + .hook_mask = (1 << NF_BR_PRE_ROUTING) | + (1 << NF_BR_LOCAL_IN) | (1 << NF_BR_FORWARD) | - (1 << NF_BR_LOCAL_OUT), + (1 << NF_BR_LOCAL_OUT) | + (1 << NF_BR_POST_ROUTING), }; static int __init nf_tables_bridge_init(void) |
