1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * xfrm6_input.c: based on net/ipv4/xfrm4_input.c
4 *
5 * Authors:
6 * Mitsuru KANDA @USAGI
7 * Kazunori MIYAZAWA @USAGI
8 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
9 * YOSHIFUJI Hideaki @USAGI
10 * IPv6 support
11 */
12
13 #include <linux/module.h>
14 #include <linux/string.h>
15 #include <linux/netfilter.h>
16 #include <linux/netfilter_ipv6.h>
17 #include <net/ipv6.h>
18 #include <net/xfrm.h>
19
xfrm6_extract_input(struct xfrm_state * x,struct sk_buff * skb)20 int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb)
21 {
22 return xfrm6_extract_header(skb);
23 }
24
xfrm6_rcv_spi(struct sk_buff * skb,int nexthdr,__be32 spi,struct ip6_tnl * t)25 int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi,
26 struct ip6_tnl *t)
27 {
28 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
29 XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
30 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
31 return xfrm_input(skb, nexthdr, spi, 0);
32 }
33 EXPORT_SYMBOL(xfrm6_rcv_spi);
34
xfrm6_transport_finish2(struct net * net,struct sock * sk,struct sk_buff * skb)35 static int xfrm6_transport_finish2(struct net *net, struct sock *sk,
36 struct sk_buff *skb)
37 {
38 if (xfrm_trans_queue(skb, ip6_rcv_finish))
39 __kfree_skb(skb);
40 return -1;
41 }
42
xfrm6_transport_finish(struct sk_buff * skb,int async)43 int xfrm6_transport_finish(struct sk_buff *skb, int async)
44 {
45 struct xfrm_offload *xo = xfrm_offload(skb);
46 int nhlen = skb->data - skb_network_header(skb);
47
48 skb_network_header(skb)[IP6CB(skb)->nhoff] =
49 XFRM_MODE_SKB_CB(skb)->protocol;
50
51 #ifndef CONFIG_NETFILTER
52 if (!async)
53 return 1;
54 #endif
55
56 __skb_push(skb, nhlen);
57 ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
58 skb_postpush_rcsum(skb, skb_network_header(skb), nhlen);
59
60 if (xo && (xo->flags & XFRM_GRO)) {
61 skb_mac_header_rebuild(skb);
62 skb_reset_transport_header(skb);
63 return -1;
64 }
65
66 NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
67 dev_net(skb->dev), NULL, skb, skb->dev, NULL,
68 xfrm6_transport_finish2);
69 return -1;
70 }
71
xfrm6_rcv_tnl(struct sk_buff * skb,struct ip6_tnl * t)72 int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t)
73 {
74 return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
75 0, t);
76 }
77 EXPORT_SYMBOL(xfrm6_rcv_tnl);
78
xfrm6_rcv(struct sk_buff * skb)79 int xfrm6_rcv(struct sk_buff *skb)
80 {
81 return xfrm6_rcv_tnl(skb, NULL);
82 }
83 EXPORT_SYMBOL(xfrm6_rcv);
xfrm6_input_addr(struct sk_buff * skb,xfrm_address_t * daddr,xfrm_address_t * saddr,u8 proto)84 int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
85 xfrm_address_t *saddr, u8 proto)
86 {
87 struct net *net = dev_net(skb->dev);
88 struct xfrm_state *x = NULL;
89 int i = 0;
90
91 if (secpath_set(skb)) {
92 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
93 goto drop;
94 }
95
96 if (1 + skb->sp->len == XFRM_MAX_DEPTH) {
97 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
98 goto drop;
99 }
100
101 for (i = 0; i < 3; i++) {
102 xfrm_address_t *dst, *src;
103
104 switch (i) {
105 case 0:
106 dst = daddr;
107 src = saddr;
108 break;
109 case 1:
110 /* lookup state with wild-card source address */
111 dst = daddr;
112 src = (xfrm_address_t *)&in6addr_any;
113 break;
114 default:
115 /* lookup state with wild-card addresses */
116 dst = (xfrm_address_t *)&in6addr_any;
117 src = (xfrm_address_t *)&in6addr_any;
118 break;
119 }
120
121 x = xfrm_state_lookup_byaddr(net, skb->mark, dst, src, proto, AF_INET6);
122 if (!x)
123 continue;
124
125 spin_lock(&x->lock);
126
127 if ((!i || (x->props.flags & XFRM_STATE_WILDRECV)) &&
128 likely(x->km.state == XFRM_STATE_VALID) &&
129 !xfrm_state_check_expire(x)) {
130 spin_unlock(&x->lock);
131 if (x->type->input(x, skb) > 0) {
132 /* found a valid state */
133 break;
134 }
135 } else
136 spin_unlock(&x->lock);
137
138 xfrm_state_put(x);
139 x = NULL;
140 }
141
142 if (!x) {
143 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
144 xfrm_audit_state_notfound_simple(skb, AF_INET6);
145 goto drop;
146 }
147
148 skb->sp->xvec[skb->sp->len++] = x;
149
150 spin_lock(&x->lock);
151
152 x->curlft.bytes += skb->len;
153 x->curlft.packets++;
154
155 spin_unlock(&x->lock);
156
157 return 1;
158
159 drop:
160 return -1;
161 }
162 EXPORT_SYMBOL(xfrm6_input_addr);
163
