diff options
Diffstat (limited to 'include/net/netfilter/nf_tables_ipv4.h')
-rw-r--r-- | include/net/netfilter/nf_tables_ipv4.h | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/include/net/netfilter/nf_tables_ipv4.h b/include/net/netfilter/nf_tables_ipv4.h new file mode 100644 index 000000000..1f7bea39a --- /dev/null +++ b/include/net/netfilter/nf_tables_ipv4.h @@ -0,0 +1,89 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _NF_TABLES_IPV4_H_ +#define _NF_TABLES_IPV4_H_ + +#include <net/netfilter/nf_tables.h> +#include <net/ip.h> + +static inline void nft_set_pktinfo_ipv4(struct nft_pktinfo *pkt, + struct sk_buff *skb) +{ + struct iphdr *ip; + + ip = ip_hdr(pkt->skb); + pkt->tprot_set = true; + pkt->tprot = ip->protocol; + pkt->xt.thoff = ip_hdrlen(pkt->skb); + pkt->xt.fragoff = ntohs(ip->frag_off) & IP_OFFSET; +} + +static inline int __nft_set_pktinfo_ipv4_validate(struct nft_pktinfo *pkt, + struct sk_buff *skb) +{ + struct iphdr *iph, _iph; + u32 len, thoff; + + iph = skb_header_pointer(skb, skb_network_offset(skb), sizeof(*iph), + &_iph); + if (!iph) + return -1; + + if (iph->ihl < 5 || iph->version != 4) + return -1; + + len = ntohs(iph->tot_len); + thoff = iph->ihl * 4; + if (skb->len < len) + return -1; + else if (len < thoff) + return -1; + + pkt->tprot_set = true; + pkt->tprot = iph->protocol; + pkt->xt.thoff = thoff; + pkt->xt.fragoff = ntohs(iph->frag_off) & IP_OFFSET; + + return 0; +} + +static inline void nft_set_pktinfo_ipv4_validate(struct nft_pktinfo *pkt, + struct sk_buff *skb) +{ + if (__nft_set_pktinfo_ipv4_validate(pkt, skb) < 0) + nft_set_pktinfo_unspec(pkt, skb); +} + +static inline int nft_set_pktinfo_ipv4_ingress(struct nft_pktinfo *pkt, + struct sk_buff *skb) +{ + struct iphdr *iph; + u32 len, thoff; + + if (!pskb_may_pull(skb, sizeof(*iph))) + return -1; + + iph = ip_hdr(skb); + if (iph->ihl < 5 || iph->version != 4) + goto inhdr_error; + + len = ntohs(iph->tot_len); + thoff = iph->ihl * 4; + if (skb->len < len) { + __IP_INC_STATS(nft_net(pkt), IPSTATS_MIB_INTRUNCATEDPKTS); + return -1; + } else if (len < thoff) { + goto inhdr_error; + } + + pkt->tprot_set = true; + pkt->tprot = iph->protocol; + pkt->xt.thoff = thoff; + pkt->xt.fragoff = ntohs(iph->frag_off) & IP_OFFSET; + + return 0; + +inhdr_error: + __IP_INC_STATS(nft_net(pkt), IPSTATS_MIB_INHDRERRORS); + return -1; +} +#endif |