1 /* 2 * xfrm6_input.c: based on net/ipv4/xfrm4_input.c 3 * 4 * Authors: 5 * Mitsuru KANDA @USAGI 6 * Kazunori MIYAZAWA @USAGI 7 * Kunihiro Ishiguro <kunihiro@ipinfusion.com> 8 * YOSHIFUJI Hideaki @USAGI 9 * IPv6 support 10 */ 11 12 #include <linux/module.h> 13 #include <linux/string.h> 14 #include <linux/netfilter.h> 15 #include <linux/netfilter_ipv6.h> 16 #include <net/ipv6.h> 17 #include <net/xfrm.h> 18 19 int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb) 20 { 21 return xfrm6_extract_header(skb); 22 } 23 24 int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi) 25 { 26 XFRM_SPI_SKB_CB(skb)->family = AF_INET6; 27 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); 28 return xfrm_input(skb, nexthdr, spi, 0); 29 } 30 EXPORT_SYMBOL(xfrm6_rcv_spi); 31 32 int xfrm6_transport_finish(struct sk_buff *skb, int async) 33 { 34 skb_network_header(skb)[IP6CB(skb)->nhoff] = 35 XFRM_MODE_SKB_CB(skb)->protocol; 36 37 #ifndef CONFIG_NETFILTER 38 if (!async) 39 return 1; 40 #endif 41 42 ipv6_hdr(skb)->payload_len = htons(skb->len); 43 __skb_push(skb, skb->data - skb_network_header(skb)); 44 45 NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, skb->dev, NULL, 46 ip6_rcv_finish); 47 return -1; 48 } 49 50 int xfrm6_rcv(struct sk_buff *skb) 51 { 52 return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff], 53 0); 54 } 55 EXPORT_SYMBOL(xfrm6_rcv); 56 57 int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr, 58 xfrm_address_t *saddr, u8 proto) 59 { 60 struct net *net = dev_net(skb->dev); 61 struct xfrm_state *x = NULL; 62 int i = 0; 63 64 /* Allocate new secpath or COW existing one. */ 65 if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) { 66 struct sec_path *sp; 67 68 sp = secpath_dup(skb->sp); 69 if (!sp) { 70 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR); 71 goto drop; 72 } 73 if (skb->sp) 74 secpath_put(skb->sp); 75 skb->sp = sp; 76 } 77 78 if (1 + skb->sp->len == XFRM_MAX_DEPTH) { 79 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); 80 goto drop; 81 } 82 83 for (i = 0; i < 3; i++) { 84 xfrm_address_t *dst, *src; 85 86 switch (i) { 87 case 0: 88 dst = daddr; 89 src = saddr; 90 break; 91 case 1: 92 /* lookup state with wild-card source address */ 93 dst = daddr; 94 src = (xfrm_address_t *)&in6addr_any; 95 break; 96 default: 97 /* lookup state with wild-card addresses */ 98 dst = (xfrm_address_t *)&in6addr_any; 99 src = (xfrm_address_t *)&in6addr_any; 100 break; 101 } 102 103 x = xfrm_state_lookup_byaddr(net, skb->mark, dst, src, proto, AF_INET6); 104 if (!x) 105 continue; 106 107 spin_lock(&x->lock); 108 109 if ((!i || (x->props.flags & XFRM_STATE_WILDRECV)) && 110 likely(x->km.state == XFRM_STATE_VALID) && 111 !xfrm_state_check_expire(x)) { 112 spin_unlock(&x->lock); 113 if (x->type->input(x, skb) > 0) { 114 /* found a valid state */ 115 break; 116 } 117 } else 118 spin_unlock(&x->lock); 119 120 xfrm_state_put(x); 121 x = NULL; 122 } 123 124 if (!x) { 125 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); 126 xfrm_audit_state_notfound_simple(skb, AF_INET6); 127 goto drop; 128 } 129 130 skb->sp->xvec[skb->sp->len++] = x; 131 132 spin_lock(&x->lock); 133 134 x->curlft.bytes += skb->len; 135 x->curlft.packets++; 136 137 spin_unlock(&x->lock); 138 139 return 1; 140 141 drop: 142 return -1; 143 } 144 EXPORT_SYMBOL(xfrm6_input_addr); 145