target/linux/generic/backport-4.19/302-v4.16-netfilter-nf_tables_inet-don-t-use-multihook-infrast.patch

   1 From: Pablo Neira Ayuso <pablo@netfilter.org>
   2 Date: Sat, 9 Dec 2017 15:36:24 +0100
   3 Subject: [PATCH] netfilter: nf_tables_inet: don't use multihook infrastructure
   4  anymore
   5
   6 Use new native NFPROTO_INET support in netfilter core, this gets rid of
   7 ad-hoc code in the nf_tables API codebase.
   8
   9 Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
  10 ---
  11
  12 --- a/include/net/netfilter/nf_tables_ipv4.h
  13 +++ b/include/net/netfilter/nf_tables_ipv4.h
  14 @@ -53,6 +53,4 @@ static inline void nft_set_pktinfo_ipv4_
  15                 nft_set_pktinfo_unspec(pkt, skb);
  16  }
  17
  18 -extern struct nft_af_info nft_af_ipv4;
  19 -
  20  #endif
  21 --- a/include/net/netfilter/nf_tables_ipv6.h
  22 +++ b/include/net/netfilter/nf_tables_ipv6.h
  23 @@ -69,6 +69,4 @@ static inline void nft_set_pktinfo_ipv6_
  24                 nft_set_pktinfo_unspec(pkt, skb);
  25  }
  26
  27 -extern struct nft_af_info nft_af_ipv6;
  28 -
  29  #endif
  30 --- a/net/ipv4/netfilter/nf_tables_ipv4.c
  31 +++ b/net/ipv4/netfilter/nf_tables_ipv4.c
  32 @@ -45,7 +45,7 @@ static unsigned int nft_ipv4_output(void
  33         return nft_do_chain_ipv4(priv, skb, state);
  34  }
  35
  36 -struct nft_af_info nft_af_ipv4 __read_mostly = {
  37 +static struct nft_af_info nft_af_ipv4 __read_mostly = {
  38         .family         = NFPROTO_IPV4,
  39         .nhooks         = NF_INET_NUMHOOKS,
  40         .owner          = THIS_MODULE,
  41 @@ -58,7 +58,6 @@ struct nft_af_info nft_af_ipv4 __read_mo
  42                 [NF_INET_POST_ROUTING]  = nft_do_chain_ipv4,
  43         },
  44  };
  45 -EXPORT_SYMBOL_GPL(nft_af_ipv4);
  46
  47  static int nf_tables_ipv4_init_net(struct net *net)
  48  {
  49 --- a/net/ipv6/netfilter/nf_tables_ipv6.c
  50 +++ b/net/ipv6/netfilter/nf_tables_ipv6.c
  51 @@ -42,7 +42,7 @@ static unsigned int nft_ipv6_output(void
  52         return nft_do_chain_ipv6(priv, skb, state);
  53  }
  54
  55 -struct nft_af_info nft_af_ipv6 __read_mostly = {
  56 +static struct nft_af_info nft_af_ipv6 __read_mostly = {
  57         .family         = NFPROTO_IPV6,
  58         .nhooks         = NF_INET_NUMHOOKS,
  59         .owner          = THIS_MODULE,
  60 @@ -55,7 +55,6 @@ struct nft_af_info nft_af_ipv6 __read_mo
  61                 [NF_INET_POST_ROUTING]  = nft_do_chain_ipv6,
  62         },
  63  };
  64 -EXPORT_SYMBOL_GPL(nft_af_ipv6);
  65
  66  static int nf_tables_ipv6_init_net(struct net *net)
  67  {
  68 --- a/net/netfilter/nf_tables_inet.c
  69 +++ b/net/netfilter/nf_tables_inet.c
  70 @@ -9,6 +9,7 @@
  71  #include <linux/init.h>
  72  #include <linux/module.h>
  73  #include <linux/ip.h>
  74 +#include <linux/ipv6.h>
  75  #include <linux/netfilter_ipv4.h>
  76  #include <linux/netfilter_ipv6.h>
  77  #include <net/netfilter/nf_tables.h>
  78 @@ -16,26 +17,71 @@
  79  #include <net/netfilter/nf_tables_ipv6.h>
  80  #include <net/ip.h>
  81
  82 -static void nft_inet_hook_ops_init(struct nf_hook_ops *ops, unsigned int n)
  83 +static unsigned int nft_do_chain_inet(void *priv, struct sk_buff *skb,
  84 +                                     const struct nf_hook_state *state)
  85  {
  86 -       struct nft_af_info *afi;
  87 +       struct nft_pktinfo pkt;
  88
  89 -       if (n == 1)
  90 -               afi = &nft_af_ipv4;
  91 -       else
  92 -               afi = &nft_af_ipv6;
  93 -
  94 -       ops->pf = afi->family;
  95 -       if (afi->hooks[ops->hooknum])
  96 -               ops->hook = afi->hooks[ops->hooknum];
  97 +       nft_set_pktinfo(&pkt, skb, state);
  98 +
  99 +       switch (state->pf) {
 100 +       case NFPROTO_IPV4:
 101 +               nft_set_pktinfo_ipv4(&pkt, skb);
 102 +               break;
 103 +       case NFPROTO_IPV6:
 104 +               nft_set_pktinfo_ipv6(&pkt, skb);
 105 +               break;
 106 +       default:
 107 +               break;
 108 +       }
 109 +
 110 +       return nft_do_chain(&pkt, priv);
 111 +}
 112 +
 113 +static unsigned int nft_inet_output(void *priv, struct sk_buff *skb,
 114 +                                   const struct nf_hook_state *state)
 115 +{
 116 +       struct nft_pktinfo pkt;
 117 +
 118 +       nft_set_pktinfo(&pkt, skb, state);
 119 +
 120 +       switch (state->pf) {
 121 +       case NFPROTO_IPV4:
 122 +               if (unlikely(skb->len < sizeof(struct iphdr) ||
 123 +                            ip_hdr(skb)->ihl < sizeof(struct iphdr) / 4)) {
 124 +                       if (net_ratelimit())
 125 +                               pr_info("ignoring short SOCK_RAW packet\n");
 126 +                       return NF_ACCEPT;
 127 +               }
 128 +               nft_set_pktinfo_ipv4(&pkt, skb);
 129 +               break;
 130 +       case NFPROTO_IPV6:
 131 +               if (unlikely(skb->len < sizeof(struct ipv6hdr))) {
 132 +                       if (net_ratelimit())
 133 +                               pr_info("ignoring short SOCK_RAW packet\n");
 134 +                       return NF_ACCEPT;
 135 +               }
 136 +               nft_set_pktinfo_ipv6(&pkt, skb);
 137 +               break;
 138 +       default:
 139 +               break;
 140 +       }
 141 +
 142 +       return nft_do_chain(&pkt, priv);
 143  }
 144
 145  static struct nft_af_info nft_af_inet __read_mostly = {
 146         .family         = NFPROTO_INET,
 147         .nhooks         = NF_INET_NUMHOOKS,
 148         .owner          = THIS_MODULE,
 149 -       .nops           = 2,
 150 -       .hook_ops_init  = nft_inet_hook_ops_init,
 151 +       .nops           = 1,
 152 +       .hooks          = {
 153 +               [NF_INET_LOCAL_IN]      = nft_do_chain_inet,
 154 +               [NF_INET_LOCAL_OUT]     = nft_inet_output,
 155 +               [NF_INET_FORWARD]       = nft_do_chain_inet,
 156 +               [NF_INET_PRE_ROUTING]   = nft_do_chain_inet,
 157 +               [NF_INET_POST_ROUTING]  = nft_do_chain_inet,
 158 +        },
 159  };
 160
 161  static int __net_init nf_tables_inet_init_net(struct net *net)