Commit | Line | Data |
---|---|---|
d1da932e VY |
1 | /* |
2 | * IPV6 GSO/GRO offload support | |
3 | * Linux INET6 implementation | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU General Public License | |
7 | * as published by the Free Software Foundation; either version | |
8 | * 2 of the License, or (at your option) any later version. | |
9 | */ | |
10 | ||
11 | #include <linux/kernel.h> | |
12 | #include <linux/socket.h> | |
13 | #include <linux/netdevice.h> | |
14 | #include <linux/skbuff.h> | |
c6b641a4 | 15 | #include <linux/printk.h> |
d1da932e VY |
16 | |
17 | #include <net/protocol.h> | |
18 | #include <net/ipv6.h> | |
19 | ||
20 | #include "ip6_offload.h" | |
21 | ||
22 | static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto) | |
23 | { | |
24 | const struct net_offload *ops = NULL; | |
25 | ||
26 | for (;;) { | |
27 | struct ipv6_opt_hdr *opth; | |
28 | int len; | |
29 | ||
30 | if (proto != NEXTHDR_HOP) { | |
31 | ops = rcu_dereference(inet6_offloads[proto]); | |
32 | ||
33 | if (unlikely(!ops)) | |
34 | break; | |
35 | ||
36 | if (!(ops->flags & INET6_PROTO_GSO_EXTHDR)) | |
37 | break; | |
38 | } | |
39 | ||
40 | if (unlikely(!pskb_may_pull(skb, 8))) | |
41 | break; | |
42 | ||
43 | opth = (void *)skb->data; | |
44 | len = ipv6_optlen(opth); | |
45 | ||
46 | if (unlikely(!pskb_may_pull(skb, len))) | |
47 | break; | |
48 | ||
49 | proto = opth->nexthdr; | |
50 | __skb_pull(skb, len); | |
51 | } | |
52 | ||
53 | return proto; | |
54 | } | |
55 | ||
56 | static int ipv6_gso_send_check(struct sk_buff *skb) | |
57 | { | |
58 | const struct ipv6hdr *ipv6h; | |
59 | const struct net_offload *ops; | |
60 | int err = -EINVAL; | |
61 | ||
62 | if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h)))) | |
63 | goto out; | |
64 | ||
65 | ipv6h = ipv6_hdr(skb); | |
66 | __skb_pull(skb, sizeof(*ipv6h)); | |
67 | err = -EPROTONOSUPPORT; | |
68 | ||
d1da932e VY |
69 | ops = rcu_dereference(inet6_offloads[ |
70 | ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]); | |
71 | ||
f191a1d1 | 72 | if (likely(ops && ops->callbacks.gso_send_check)) { |
d1da932e | 73 | skb_reset_transport_header(skb); |
f191a1d1 | 74 | err = ops->callbacks.gso_send_check(skb); |
d1da932e | 75 | } |
d1da932e VY |
76 | |
77 | out: | |
78 | return err; | |
79 | } | |
80 | ||
81 | static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, | |
82 | netdev_features_t features) | |
83 | { | |
84 | struct sk_buff *segs = ERR_PTR(-EINVAL); | |
85 | struct ipv6hdr *ipv6h; | |
86 | const struct net_offload *ops; | |
87 | int proto; | |
88 | struct frag_hdr *fptr; | |
89 | unsigned int unfrag_ip6hlen; | |
90 | u8 *prevhdr; | |
91 | int offset = 0; | |
91a48a2e | 92 | bool encap, udpfrag; |
d3e5e006 | 93 | int nhoff; |
d1da932e | 94 | |
d1da932e VY |
95 | if (unlikely(skb_shinfo(skb)->gso_type & |
96 | ~(SKB_GSO_UDP | | |
97 | SKB_GSO_DODGY | | |
98 | SKB_GSO_TCP_ECN | | |
68c33163 | 99 | SKB_GSO_GRE | |
4749c09c | 100 | SKB_GSO_GRE_CSUM | |
cb32f511 | 101 | SKB_GSO_IPIP | |
61c1db7f | 102 | SKB_GSO_SIT | |
73136267 | 103 | SKB_GSO_UDP_TUNNEL | |
0f4f4ffa | 104 | SKB_GSO_UDP_TUNNEL_CSUM | |
0d89d203 | 105 | SKB_GSO_MPLS | |
d1da932e VY |
106 | SKB_GSO_TCPV6 | |
107 | 0))) | |
108 | goto out; | |
109 | ||
d3e5e006 ED |
110 | skb_reset_network_header(skb); |
111 | nhoff = skb_network_header(skb) - skb_mac_header(skb); | |
d1da932e VY |
112 | if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h)))) |
113 | goto out; | |
114 | ||
91a48a2e HFS |
115 | encap = SKB_GSO_CB(skb)->encap_level > 0; |
116 | if (encap) | |
d3e5e006 ED |
117 | features = skb->dev->hw_enc_features & netif_skb_features(skb); |
118 | SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h); | |
119 | ||
d1da932e VY |
120 | ipv6h = ipv6_hdr(skb); |
121 | __skb_pull(skb, sizeof(*ipv6h)); | |
122 | segs = ERR_PTR(-EPROTONOSUPPORT); | |
123 | ||
124 | proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr); | |
b917eb15 | 125 | |
91a48a2e HFS |
126 | if (skb->encapsulation && |
127 | skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP)) | |
128 | udpfrag = proto == IPPROTO_UDP && encap; | |
129 | else | |
130 | udpfrag = proto == IPPROTO_UDP && !skb->encapsulation; | |
131 | ||
d1da932e | 132 | ops = rcu_dereference(inet6_offloads[proto]); |
f191a1d1 | 133 | if (likely(ops && ops->callbacks.gso_segment)) { |
d1da932e | 134 | skb_reset_transport_header(skb); |
f191a1d1 | 135 | segs = ops->callbacks.gso_segment(skb, features); |
d1da932e | 136 | } |
d1da932e VY |
137 | |
138 | if (IS_ERR(segs)) | |
139 | goto out; | |
140 | ||
141 | for (skb = segs; skb; skb = skb->next) { | |
d3e5e006 ED |
142 | ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff); |
143 | ipv6h->payload_len = htons(skb->len - nhoff - sizeof(*ipv6h)); | |
d3e5e006 ED |
144 | skb->network_header = (u8 *)ipv6h - skb->head; |
145 | ||
91a48a2e | 146 | if (udpfrag) { |
d1da932e | 147 | unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr); |
d3e5e006 | 148 | fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen); |
d1da932e VY |
149 | fptr->frag_off = htons(offset); |
150 | if (skb->next != NULL) | |
151 | fptr->frag_off |= htons(IP6_MF); | |
152 | offset += (ntohs(ipv6h->payload_len) - | |
153 | sizeof(struct frag_hdr)); | |
154 | } | |
91a48a2e HFS |
155 | if (encap) |
156 | skb_reset_inner_headers(skb); | |
d1da932e VY |
157 | } |
158 | ||
159 | out: | |
160 | return segs; | |
161 | } | |
162 | ||
299603e8 JC |
163 | /* Return the total length of all the extension hdrs, following the same |
164 | * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs. | |
165 | */ | |
166 | static int ipv6_exthdrs_len(struct ipv6hdr *iph, | |
167 | const struct net_offload **opps) | |
168 | { | |
810c23a3 JC |
169 | struct ipv6_opt_hdr *opth = (void *)iph; |
170 | int len = 0, proto, optlen = sizeof(*iph); | |
299603e8 JC |
171 | |
172 | proto = iph->nexthdr; | |
173 | for (;;) { | |
174 | if (proto != NEXTHDR_HOP) { | |
175 | *opps = rcu_dereference(inet6_offloads[proto]); | |
176 | if (unlikely(!(*opps))) | |
177 | break; | |
178 | if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR)) | |
179 | break; | |
180 | } | |
810c23a3 JC |
181 | opth = (void *)opth + optlen; |
182 | optlen = ipv6_optlen(opth); | |
299603e8 JC |
183 | len += optlen; |
184 | proto = opth->nexthdr; | |
185 | } | |
186 | return len; | |
187 | } | |
188 | ||
d1da932e VY |
189 | static struct sk_buff **ipv6_gro_receive(struct sk_buff **head, |
190 | struct sk_buff *skb) | |
191 | { | |
192 | const struct net_offload *ops; | |
193 | struct sk_buff **pp = NULL; | |
194 | struct sk_buff *p; | |
195 | struct ipv6hdr *iph; | |
196 | unsigned int nlen; | |
197 | unsigned int hlen; | |
198 | unsigned int off; | |
bf5a755f | 199 | u16 flush = 1; |
d1da932e | 200 | int proto; |
d1da932e VY |
201 | |
202 | off = skb_gro_offset(skb); | |
203 | hlen = off + sizeof(*iph); | |
204 | iph = skb_gro_header_fast(skb, off); | |
205 | if (skb_gro_header_hard(skb, hlen)) { | |
206 | iph = skb_gro_header_slow(skb, hlen, off); | |
207 | if (unlikely(!iph)) | |
208 | goto out; | |
209 | } | |
210 | ||
299603e8 | 211 | skb_set_network_header(skb, off); |
d1da932e VY |
212 | skb_gro_pull(skb, sizeof(*iph)); |
213 | skb_set_transport_header(skb, skb_gro_offset(skb)); | |
214 | ||
215 | flush += ntohs(iph->payload_len) != skb_gro_len(skb); | |
216 | ||
217 | rcu_read_lock(); | |
218 | proto = iph->nexthdr; | |
219 | ops = rcu_dereference(inet6_offloads[proto]); | |
f191a1d1 | 220 | if (!ops || !ops->callbacks.gro_receive) { |
d1da932e VY |
221 | __pskb_pull(skb, skb_gro_offset(skb)); |
222 | proto = ipv6_gso_pull_exthdrs(skb, proto); | |
223 | skb_gro_pull(skb, -skb_transport_offset(skb)); | |
224 | skb_reset_transport_header(skb); | |
225 | __skb_push(skb, skb_gro_offset(skb)); | |
226 | ||
227 | ops = rcu_dereference(inet6_offloads[proto]); | |
f191a1d1 | 228 | if (!ops || !ops->callbacks.gro_receive) |
d1da932e VY |
229 | goto out_unlock; |
230 | ||
231 | iph = ipv6_hdr(skb); | |
232 | } | |
233 | ||
234 | NAPI_GRO_CB(skb)->proto = proto; | |
235 | ||
236 | flush--; | |
237 | nlen = skb_network_header_len(skb); | |
238 | ||
239 | for (p = *head; p; p = p->next) { | |
240 | const struct ipv6hdr *iph2; | |
241 | __be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */ | |
242 | ||
243 | if (!NAPI_GRO_CB(p)->same_flow) | |
244 | continue; | |
245 | ||
299603e8 | 246 | iph2 = (struct ipv6hdr *)(p->data + off); |
d1da932e VY |
247 | first_word = *(__be32 *)iph ^ *(__be32 *)iph2 ; |
248 | ||
299603e8 JC |
249 | /* All fields must match except length and Traffic Class. |
250 | * XXX skbs on the gro_list have all been parsed and pulled | |
251 | * already so we don't need to compare nlen | |
252 | * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops))) | |
253 | * memcmp() alone below is suffcient, right? | |
254 | */ | |
255 | if ((first_word & htonl(0xF00FFFFF)) || | |
d1da932e VY |
256 | memcmp(&iph->nexthdr, &iph2->nexthdr, |
257 | nlen - offsetof(struct ipv6hdr, nexthdr))) { | |
258 | NAPI_GRO_CB(p)->same_flow = 0; | |
259 | continue; | |
260 | } | |
261 | /* flush if Traffic Class fields are different */ | |
262 | NAPI_GRO_CB(p)->flush |= !!(first_word & htonl(0x0FF00000)); | |
263 | NAPI_GRO_CB(p)->flush |= flush; | |
264 | } | |
265 | ||
266 | NAPI_GRO_CB(skb)->flush |= flush; | |
267 | ||
4de462ab | 268 | skb_gro_postpull_rcsum(skb, iph, nlen); |
d1da932e | 269 | |
f191a1d1 | 270 | pp = ops->callbacks.gro_receive(head, skb); |
d1da932e | 271 | |
d1da932e VY |
272 | out_unlock: |
273 | rcu_read_unlock(); | |
274 | ||
275 | out: | |
276 | NAPI_GRO_CB(skb)->flush |= flush; | |
277 | ||
278 | return pp; | |
279 | } | |
280 | ||
299603e8 | 281 | static int ipv6_gro_complete(struct sk_buff *skb, int nhoff) |
d1da932e VY |
282 | { |
283 | const struct net_offload *ops; | |
299603e8 | 284 | struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + nhoff); |
d1da932e VY |
285 | int err = -ENOSYS; |
286 | ||
299603e8 | 287 | iph->payload_len = htons(skb->len - nhoff - sizeof(*iph)); |
d1da932e VY |
288 | |
289 | rcu_read_lock(); | |
299603e8 JC |
290 | |
291 | nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops); | |
f191a1d1 | 292 | if (WARN_ON(!ops || !ops->callbacks.gro_complete)) |
d1da932e VY |
293 | goto out_unlock; |
294 | ||
299603e8 | 295 | err = ops->callbacks.gro_complete(skb, nhoff); |
d1da932e VY |
296 | |
297 | out_unlock: | |
298 | rcu_read_unlock(); | |
299 | ||
300 | return err; | |
301 | } | |
302 | ||
303 | static struct packet_offload ipv6_packet_offload __read_mostly = { | |
304 | .type = cpu_to_be16(ETH_P_IPV6), | |
f191a1d1 VY |
305 | .callbacks = { |
306 | .gso_send_check = ipv6_gso_send_check, | |
307 | .gso_segment = ipv6_gso_segment, | |
308 | .gro_receive = ipv6_gro_receive, | |
309 | .gro_complete = ipv6_gro_complete, | |
310 | }, | |
d1da932e VY |
311 | }; |
312 | ||
61c1db7f ED |
313 | static const struct net_offload sit_offload = { |
314 | .callbacks = { | |
315 | .gso_send_check = ipv6_gso_send_check, | |
316 | .gso_segment = ipv6_gso_segment, | |
317 | }, | |
318 | }; | |
319 | ||
c6b641a4 | 320 | static int __init ipv6_offload_init(void) |
d1da932e | 321 | { |
c6b641a4 VY |
322 | |
323 | if (tcpv6_offload_init() < 0) | |
324 | pr_crit("%s: Cannot add TCP protocol offload\n", __func__); | |
325 | if (udp_offload_init() < 0) | |
326 | pr_crit("%s: Cannot add UDP protocol offload\n", __func__); | |
327 | if (ipv6_exthdrs_offload_init() < 0) | |
328 | pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__); | |
329 | ||
d1da932e | 330 | dev_add_offload(&ipv6_packet_offload); |
61c1db7f ED |
331 | |
332 | inet_add_offload(&sit_offload, IPPROTO_IPV6); | |
333 | ||
c6b641a4 | 334 | return 0; |
d1da932e VY |
335 | } |
336 | ||
c6b641a4 | 337 | fs_initcall(ipv6_offload_init); |