Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * xfrm6_input.c: based on net/ipv4/xfrm4_input.c | |
4 | * | |
5 | * Authors: | |
6 | * Mitsuru KANDA @USAGI | |
67ba4152 IM |
7 | * Kazunori MIYAZAWA @USAGI |
8 | * Kunihiro Ishiguro <kunihiro@ipinfusion.com> | |
1da177e4 LT |
9 | * YOSHIFUJI Hideaki @USAGI |
10 | * IPv6 support | |
11 | */ | |
12 | ||
13 | #include <linux/module.h> | |
14 | #include <linux/string.h> | |
b05e1066 PM |
15 | #include <linux/netfilter.h> |
16 | #include <linux/netfilter_ipv6.h> | |
1da177e4 LT |
17 | #include <net/ipv6.h> |
18 | #include <net/xfrm.h> | |
221ddb72 SK |
19 | #include <net/protocol.h> |
20 | #include <net/gro.h> | |
1da177e4 | 21 | |
63c43787 ND |
22 | int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi, |
23 | struct ip6_tnl *t) | |
1da177e4 | 24 | { |
63c43787 | 25 | XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t; |
2fcb45b6 | 26 | XFRM_SPI_SKB_CB(skb)->family = AF_INET6; |
716062fd HX |
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); | |
b05e1066 | 31 | |
acf568ee HX |
32 | static int xfrm6_transport_finish2(struct net *net, struct sock *sk, |
33 | struct sk_buff *skb) | |
34 | { | |
0146dca7 SD |
35 | if (xfrm_trans_queue(skb, ip6_rcv_finish)) { |
36 | kfree_skb(skb); | |
37 | return NET_RX_DROP; | |
38 | } | |
39 | ||
40 | return 0; | |
acf568ee HX |
41 | } |
42 | ||
716062fd HX |
43 | int xfrm6_transport_finish(struct sk_buff *skb, int async) |
44 | { | |
7785bba2 | 45 | struct xfrm_offload *xo = xfrm_offload(skb); |
e9cba694 | 46 | int nhlen = skb->data - skb_network_header(skb); |
7785bba2 | 47 | |
60d5fcfb HX |
48 | skb_network_header(skb)[IP6CB(skb)->nhoff] = |
49 | XFRM_MODE_SKB_CB(skb)->protocol; | |
50 | ||
0883ae0e HX |
51 | #ifndef CONFIG_NETFILTER |
52 | if (!async) | |
53 | return 1; | |
54 | #endif | |
55 | ||
e9cba694 | 56 | __skb_push(skb, nhlen); |
7c88e21a | 57 | ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); |
e9cba694 | 58 | skb_postpush_rcsum(skb, skb_network_header(skb), nhlen); |
b05e1066 | 59 | |
7785bba2 SK |
60 | if (xo && (xo->flags & XFRM_GRO)) { |
61 | skb_mac_header_rebuild(skb); | |
bfc0698b | 62 | skb_reset_transport_header(skb); |
0146dca7 | 63 | return 0; |
7785bba2 SK |
64 | } |
65 | ||
29a26a56 EB |
66 | NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, |
67 | dev_net(skb->dev), NULL, skb, skb->dev, NULL, | |
acf568ee | 68 | xfrm6_transport_finish2); |
0146dca7 SD |
69 | return 0; |
70 | } | |
71 | ||
221ddb72 | 72 | static int __xfrm6_udp_encap_rcv(struct sock *sk, struct sk_buff *skb, bool pull) |
0146dca7 SD |
73 | { |
74 | struct udp_sock *up = udp_sk(sk); | |
75 | struct udphdr *uh; | |
76 | struct ipv6hdr *ip6h; | |
77 | int len; | |
78 | int ip6hlen = sizeof(struct ipv6hdr); | |
0146dca7 SD |
79 | __u8 *udpdata; |
80 | __be32 *udpdata32; | |
70a36f57 | 81 | u16 encap_type; |
0146dca7 | 82 | |
70a36f57 | 83 | encap_type = READ_ONCE(up->encap_type); |
0146dca7 SD |
84 | /* if this is not encapsulated socket, then just return now */ |
85 | if (!encap_type) | |
86 | return 1; | |
87 | ||
88 | /* If this is a paged skb, make sure we pull up | |
89 | * whatever data we need to look at. */ | |
90 | len = skb->len - sizeof(struct udphdr); | |
91 | if (!pskb_may_pull(skb, sizeof(struct udphdr) + min(len, 8))) | |
92 | return 1; | |
93 | ||
94 | /* Now we can get the pointers */ | |
95 | uh = udp_hdr(skb); | |
96 | udpdata = (__u8 *)uh + sizeof(struct udphdr); | |
97 | udpdata32 = (__be32 *)udpdata; | |
98 | ||
99 | switch (encap_type) { | |
100 | default: | |
101 | case UDP_ENCAP_ESPINUDP: | |
102 | /* Check if this is a keepalive packet. If so, eat it. */ | |
103 | if (len == 1 && udpdata[0] == 0xff) { | |
221ddb72 | 104 | return -EINVAL; |
0146dca7 SD |
105 | } else if (len > sizeof(struct ip_esp_hdr) && udpdata32[0] != 0) { |
106 | /* ESP Packet without Non-ESP header */ | |
107 | len = sizeof(struct udphdr); | |
108 | } else | |
109 | /* Must be an IKE packet.. pass it through */ | |
110 | return 1; | |
111 | break; | |
112 | case UDP_ENCAP_ESPINUDP_NON_IKE: | |
113 | /* Check if this is a keepalive packet. If so, eat it. */ | |
114 | if (len == 1 && udpdata[0] == 0xff) { | |
221ddb72 | 115 | return -EINVAL; |
0146dca7 SD |
116 | } else if (len > 2 * sizeof(u32) + sizeof(struct ip_esp_hdr) && |
117 | udpdata32[0] == 0 && udpdata32[1] == 0) { | |
118 | ||
119 | /* ESP Packet with Non-IKE marker */ | |
120 | len = sizeof(struct udphdr) + 2 * sizeof(u32); | |
121 | } else | |
122 | /* Must be an IKE packet.. pass it through */ | |
123 | return 1; | |
124 | break; | |
125 | } | |
126 | ||
127 | /* At this point we are sure that this is an ESPinUDP packet, | |
128 | * so we need to remove 'len' bytes from the packet (the UDP | |
129 | * header and optional ESP marker bytes) and then modify the | |
130 | * protocol to ESP, and then call into the transform receiver. | |
131 | */ | |
132 | if (skb_unclone(skb, GFP_ATOMIC)) | |
221ddb72 | 133 | return -EINVAL; |
0146dca7 SD |
134 | |
135 | /* Now we can update and verify the packet length... */ | |
136 | ip6h = ipv6_hdr(skb); | |
137 | ip6h->payload_len = htons(ntohs(ip6h->payload_len) - len); | |
138 | if (skb->len < ip6hlen + len) { | |
139 | /* packet is too small!?! */ | |
221ddb72 | 140 | return -EINVAL; |
0146dca7 SD |
141 | } |
142 | ||
143 | /* pull the data buffer up to the ESP header and set the | |
144 | * transport header to point to ESP. Keep UDP on the stack | |
145 | * for later. | |
146 | */ | |
221ddb72 SK |
147 | if (pull) { |
148 | __skb_pull(skb, len); | |
149 | skb_reset_transport_header(skb); | |
150 | } else { | |
151 | skb_set_transport_header(skb, len); | |
152 | } | |
0146dca7 SD |
153 | |
154 | /* process ESP */ | |
0146dca7 | 155 | return 0; |
1da177e4 LT |
156 | } |
157 | ||
221ddb72 SK |
158 | /* If it's a keepalive packet, then just eat it. |
159 | * If it's an encapsulated packet, then pass it to the | |
160 | * IPsec xfrm input. | |
161 | * Returns 0 if skb passed to xfrm or was dropped. | |
162 | * Returns >0 if skb should be passed to UDP. | |
163 | * Returns <0 if skb should be resubmitted (-ret is protocol) | |
164 | */ | |
165 | int xfrm6_udp_encap_rcv(struct sock *sk, struct sk_buff *skb) | |
166 | { | |
167 | int ret; | |
168 | ||
53a5b4f2 SK |
169 | if (skb->protocol == htons(ETH_P_IP)) |
170 | return xfrm4_udp_encap_rcv(sk, skb); | |
171 | ||
221ddb72 SK |
172 | ret = __xfrm6_udp_encap_rcv(sk, skb, true); |
173 | if (!ret) | |
174 | return xfrm6_rcv_encap(skb, IPPROTO_ESP, 0, | |
175 | udp_sk(sk)->encap_type); | |
176 | ||
177 | if (ret < 0) { | |
178 | kfree_skb(skb); | |
179 | return 0; | |
180 | } | |
181 | ||
182 | return ret; | |
183 | } | |
184 | ||
185 | struct sk_buff *xfrm6_gro_udp_encap_rcv(struct sock *sk, struct list_head *head, | |
186 | struct sk_buff *skb) | |
187 | { | |
188 | int offset = skb_gro_offset(skb); | |
189 | const struct net_offload *ops; | |
190 | struct sk_buff *pp = NULL; | |
191 | int ret; | |
192 | ||
53a5b4f2 SK |
193 | if (skb->protocol == htons(ETH_P_IP)) |
194 | return xfrm4_gro_udp_encap_rcv(sk, head, skb); | |
195 | ||
221ddb72 SK |
196 | offset = offset - sizeof(struct udphdr); |
197 | ||
198 | if (!pskb_pull(skb, offset)) | |
199 | return NULL; | |
200 | ||
201 | rcu_read_lock(); | |
202 | ops = rcu_dereference(inet6_offloads[IPPROTO_ESP]); | |
203 | if (!ops || !ops->callbacks.gro_receive) | |
204 | goto out; | |
205 | ||
206 | ret = __xfrm6_udp_encap_rcv(sk, skb, false); | |
207 | if (ret) | |
208 | goto out; | |
209 | ||
210 | skb_push(skb, offset); | |
211 | NAPI_GRO_CB(skb)->proto = IPPROTO_UDP; | |
212 | ||
213 | pp = call_gro_receive(ops->callbacks.gro_receive, head, skb); | |
214 | rcu_read_unlock(); | |
215 | ||
216 | return pp; | |
217 | ||
218 | out: | |
219 | rcu_read_unlock(); | |
220 | skb_push(skb, offset); | |
221 | NAPI_GRO_CB(skb)->same_flow = 0; | |
222 | NAPI_GRO_CB(skb)->flush = 1; | |
223 | ||
224 | return NULL; | |
225 | } | |
226 | ||
63c43787 | 227 | int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t) |
1da177e4 | 228 | { |
33b5ecb8 | 229 | return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff], |
63c43787 | 230 | 0, t); |
1da177e4 | 231 | } |
63c43787 | 232 | EXPORT_SYMBOL(xfrm6_rcv_tnl); |
7159039a | 233 | |
63c43787 ND |
234 | int xfrm6_rcv(struct sk_buff *skb) |
235 | { | |
236 | return xfrm6_rcv_tnl(skb, NULL); | |
237 | } | |
238 | EXPORT_SYMBOL(xfrm6_rcv); | |
fbd9a5b4 MN |
239 | int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr, |
240 | xfrm_address_t *saddr, u8 proto) | |
241 | { | |
59c9940e | 242 | struct net *net = dev_net(skb->dev); |
1ab1457c | 243 | struct xfrm_state *x = NULL; |
0ca64da1 | 244 | struct sec_path *sp; |
fbd9a5b4 MN |
245 | int i = 0; |
246 | ||
0ca64da1 FW |
247 | sp = secpath_set(skb); |
248 | if (!sp) { | |
b0fcee82 SK |
249 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR); |
250 | goto drop; | |
9473e1f6 MN |
251 | } |
252 | ||
0ca64da1 | 253 | if (1 + sp->len == XFRM_MAX_DEPTH) { |
59c9940e | 254 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); |
9473e1f6 MN |
255 | goto drop; |
256 | } | |
257 | ||
fbd9a5b4 MN |
258 | for (i = 0; i < 3; i++) { |
259 | xfrm_address_t *dst, *src; | |
a002c6fd | 260 | |
fbd9a5b4 MN |
261 | switch (i) { |
262 | case 0: | |
263 | dst = daddr; | |
264 | src = saddr; | |
265 | break; | |
266 | case 1: | |
267 | /* lookup state with wild-card source address */ | |
fbd9a5b4 | 268 | dst = daddr; |
a002c6fd | 269 | src = (xfrm_address_t *)&in6addr_any; |
fbd9a5b4 | 270 | break; |
fbd9a5b4 | 271 | default: |
1ab1457c | 272 | /* lookup state with wild-card addresses */ |
a002c6fd YH |
273 | dst = (xfrm_address_t *)&in6addr_any; |
274 | src = (xfrm_address_t *)&in6addr_any; | |
fbd9a5b4 | 275 | break; |
1ab1457c | 276 | } |
fbd9a5b4 | 277 | |
bd55775c | 278 | x = xfrm_state_lookup_byaddr(net, skb->mark, dst, src, proto, AF_INET6); |
fbd9a5b4 MN |
279 | if (!x) |
280 | continue; | |
281 | ||
282 | spin_lock(&x->lock); | |
283 | ||
a002c6fd YH |
284 | if ((!i || (x->props.flags & XFRM_STATE_WILDRECV)) && |
285 | likely(x->km.state == XFRM_STATE_VALID) && | |
286 | !xfrm_state_check_expire(x)) { | |
fbd9a5b4 | 287 | spin_unlock(&x->lock); |
a002c6fd YH |
288 | if (x->type->input(x, skb) > 0) { |
289 | /* found a valid state */ | |
290 | break; | |
291 | } | |
292 | } else | |
fbd9a5b4 | 293 | spin_unlock(&x->lock); |
fbd9a5b4 | 294 | |
a002c6fd YH |
295 | xfrm_state_put(x); |
296 | x = NULL; | |
fbd9a5b4 MN |
297 | } |
298 | ||
9473e1f6 | 299 | if (!x) { |
59c9940e | 300 | XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); |
afeb14b4 | 301 | xfrm_audit_state_notfound_simple(skb, AF_INET6); |
fbd9a5b4 | 302 | goto drop; |
fbd9a5b4 MN |
303 | } |
304 | ||
2294be0f | 305 | sp->xvec[sp->len++] = x; |
9473e1f6 MN |
306 | |
307 | spin_lock(&x->lock); | |
fbd9a5b4 | 308 | |
9473e1f6 MN |
309 | x->curlft.bytes += skb->len; |
310 | x->curlft.packets++; | |
311 | ||
312 | spin_unlock(&x->lock); | |
fbd9a5b4 MN |
313 | |
314 | return 1; | |
9473e1f6 | 315 | |
fbd9a5b4 | 316 | drop: |
fbd9a5b4 MN |
317 | return -1; |
318 | } | |
7159039a | 319 | EXPORT_SYMBOL(xfrm6_input_addr); |