root/include/net/netfilter/nf_tables_ipv4.h

INCLUDED FROM

DEFINITIONS

1. nft_set_pktinfo_ipv4
2. __nft_set_pktinfo_ipv4_validate
3. nft_set_pktinfo_ipv4_validate

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _NF_TABLES_IPV4_H_
   3 #define _NF_TABLES_IPV4_H_
   4 
   5 #include <net/netfilter/nf_tables.h>
   6 #include <net/ip.h>
   7 
   8 static inline void nft_set_pktinfo_ipv4(struct nft_pktinfo *pkt,
   9                                         struct sk_buff *skb)
  10 {
  11         struct iphdr *ip;
  12 
  13         ip = ip_hdr(pkt->skb);
  14         pkt->tprot_set = true;
  15         pkt->tprot = ip->protocol;
  16         pkt->xt.thoff = ip_hdrlen(pkt->skb);
  17         pkt->xt.fragoff = ntohs(ip->frag_off) & IP_OFFSET;
  18 }
  19 
  20 static inline int __nft_set_pktinfo_ipv4_validate(struct nft_pktinfo *pkt,
  21                                                   struct sk_buff *skb)
  22 {
  23         struct iphdr *iph, _iph;
  24         u32 len, thoff;
  25 
  26         iph = skb_header_pointer(skb, skb_network_offset(skb), sizeof(*iph),
  27                                  &_iph);
  28         if (!iph)
  29                 return -1;
  30 
  31         if (iph->ihl < 5 || iph->version != 4)
  32                 return -1;
  33 
  34         len = ntohs(iph->tot_len);
  35         thoff = iph->ihl * 4;
  36         if (skb->len < len)
  37                 return -1;
  38         else if (len < thoff)
  39                 return -1;
  40 
  41         pkt->tprot_set = true;
  42         pkt->tprot = iph->protocol;
  43         pkt->xt.thoff = thoff;
  44         pkt->xt.fragoff = ntohs(iph->frag_off) & IP_OFFSET;
  45 
  46         return 0;
  47 }
  48 
  49 static inline void nft_set_pktinfo_ipv4_validate(struct nft_pktinfo *pkt,
  50                                                  struct sk_buff *skb)
  51 {
  52         if (__nft_set_pktinfo_ipv4_validate(pkt, skb) < 0)
  53                 nft_set_pktinfo_unspec(pkt, skb);
  54 }
  55 
  56 #endif