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 | |
cb32f511 | 100 | SKB_GSO_IPIP | |
61c1db7f | 101 | SKB_GSO_SIT | |
73136267 | 102 | SKB_GSO_UDP_TUNNEL | |
0d89d203 | 103 | SKB_GSO_MPLS | |
d1da932e VY |
104 | SKB_GSO_TCPV6 | |
105 | 0))) | |
106 | goto out; | |
107 | ||
d3e5e006 ED |
108 | skb_reset_network_header(skb); |
109 | nhoff = skb_network_header(skb) - skb_mac_header(skb); | |
d1da932e VY |
110 | if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h)))) |
111 | goto out; | |
112 | ||
91a48a2e HFS |
113 | encap = SKB_GSO_CB(skb)->encap_level > 0; |
114 | if (encap) | |
d3e5e006 ED |
115 | features = skb->dev->hw_enc_features & netif_skb_features(skb); |
116 | SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h); | |
117 | ||
d1da932e VY |
118 | ipv6h = ipv6_hdr(skb); |
119 | __skb_pull(skb, sizeof(*ipv6h)); | |
120 | segs = ERR_PTR(-EPROTONOSUPPORT); | |
121 | ||
122 | proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr); | |
b917eb15 | 123 | |
91a48a2e HFS |
124 | if (skb->encapsulation && |
125 | skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP)) | |
126 | udpfrag = proto == IPPROTO_UDP && encap; | |
127 | else | |
128 | udpfrag = proto == IPPROTO_UDP && !skb->encapsulation; | |
129 | ||
d1da932e | 130 | ops = rcu_dereference(inet6_offloads[proto]); |
f191a1d1 | 131 | if (likely(ops && ops->callbacks.gso_segment)) { |
d1da932e | 132 | skb_reset_transport_header(skb); |
f191a1d1 | 133 | segs = ops->callbacks.gso_segment(skb, features); |
d1da932e | 134 | } |
d1da932e VY |
135 | |
136 | if (IS_ERR(segs)) | |
137 | goto out; | |
138 | ||
139 | for (skb = segs; skb; skb = skb->next) { | |
d3e5e006 ED |
140 | ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff); |
141 | ipv6h->payload_len = htons(skb->len - nhoff - sizeof(*ipv6h)); | |
d3e5e006 ED |
142 | skb->network_header = (u8 *)ipv6h - skb->head; |
143 | ||
91a48a2e | 144 | if (udpfrag) { |
d1da932e | 145 | unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr); |
d3e5e006 | 146 | fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen); |
d1da932e VY |
147 | fptr->frag_off = htons(offset); |
148 | if (skb->next != NULL) | |
149 | fptr->frag_off |= htons(IP6_MF); | |
150 | offset += (ntohs(ipv6h->payload_len) - | |
151 | sizeof(struct frag_hdr)); | |
152 | } | |
91a48a2e HFS |
153 | if (encap) |
154 | skb_reset_inner_headers(skb); | |
d1da932e VY |
155 | } |
156 | ||
157 | out: | |
158 | return segs; | |
159 | } | |
160 | ||
299603e8 JC |
161 | /* Return the total length of all the extension hdrs, following the same |
162 | * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs. | |
163 | */ | |
164 | static int ipv6_exthdrs_len(struct ipv6hdr *iph, | |
165 | const struct net_offload **opps) | |
166 | { | |
810c23a3 JC |
167 | struct ipv6_opt_hdr *opth = (void *)iph; |
168 | int len = 0, proto, optlen = sizeof(*iph); | |
299603e8 JC |
169 | |
170 | proto = iph->nexthdr; | |
171 | for (;;) { | |
172 | if (proto != NEXTHDR_HOP) { | |
173 | *opps = rcu_dereference(inet6_offloads[proto]); | |
174 | if (unlikely(!(*opps))) | |
175 | break; | |
176 | if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR)) | |
177 | break; | |
178 | } | |
810c23a3 JC |
179 | opth = (void *)opth + optlen; |
180 | optlen = ipv6_optlen(opth); | |
299603e8 JC |
181 | len += optlen; |
182 | proto = opth->nexthdr; | |
183 | } | |
184 | return len; | |
185 | } | |
186 | ||
d1da932e VY |
187 | static struct sk_buff **ipv6_gro_receive(struct sk_buff **head, |
188 | struct sk_buff *skb) | |
189 | { | |
190 | const struct net_offload *ops; | |
191 | struct sk_buff **pp = NULL; | |
192 | struct sk_buff *p; | |
193 | struct ipv6hdr *iph; | |
194 | unsigned int nlen; | |
195 | unsigned int hlen; | |
196 | unsigned int off; | |
bf5a755f | 197 | u16 flush = 1; |
d1da932e | 198 | int proto; |
d1da932e VY |
199 | |
200 | off = skb_gro_offset(skb); | |
201 | hlen = off + sizeof(*iph); | |
202 | iph = skb_gro_header_fast(skb, off); | |
203 | if (skb_gro_header_hard(skb, hlen)) { | |
204 | iph = skb_gro_header_slow(skb, hlen, off); | |
205 | if (unlikely(!iph)) | |
206 | goto out; | |
207 | } | |
208 | ||
299603e8 | 209 | skb_set_network_header(skb, off); |
d1da932e VY |
210 | skb_gro_pull(skb, sizeof(*iph)); |
211 | skb_set_transport_header(skb, skb_gro_offset(skb)); | |
212 | ||
213 | flush += ntohs(iph->payload_len) != skb_gro_len(skb); | |
214 | ||
215 | rcu_read_lock(); | |
216 | proto = iph->nexthdr; | |
217 | ops = rcu_dereference(inet6_offloads[proto]); | |
f191a1d1 | 218 | if (!ops || !ops->callbacks.gro_receive) { |
d1da932e VY |
219 | __pskb_pull(skb, skb_gro_offset(skb)); |
220 | proto = ipv6_gso_pull_exthdrs(skb, proto); | |
221 | skb_gro_pull(skb, -skb_transport_offset(skb)); | |
222 | skb_reset_transport_header(skb); | |
223 | __skb_push(skb, skb_gro_offset(skb)); | |
224 | ||
225 | ops = rcu_dereference(inet6_offloads[proto]); | |
f191a1d1 | 226 | if (!ops || !ops->callbacks.gro_receive) |
d1da932e VY |
227 | goto out_unlock; |
228 | ||
229 | iph = ipv6_hdr(skb); | |
230 | } | |
231 | ||
232 | NAPI_GRO_CB(skb)->proto = proto; | |
233 | ||
234 | flush--; | |
235 | nlen = skb_network_header_len(skb); | |
236 | ||
237 | for (p = *head; p; p = p->next) { | |
238 | const struct ipv6hdr *iph2; | |
239 | __be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */ | |
240 | ||
241 | if (!NAPI_GRO_CB(p)->same_flow) | |
242 | continue; | |
243 | ||
299603e8 | 244 | iph2 = (struct ipv6hdr *)(p->data + off); |
d1da932e VY |
245 | first_word = *(__be32 *)iph ^ *(__be32 *)iph2 ; |
246 | ||
299603e8 JC |
247 | /* All fields must match except length and Traffic Class. |
248 | * XXX skbs on the gro_list have all been parsed and pulled | |
249 | * already so we don't need to compare nlen | |
250 | * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops))) | |
251 | * memcmp() alone below is suffcient, right? | |
252 | */ | |
253 | if ((first_word & htonl(0xF00FFFFF)) || | |
d1da932e VY |
254 | memcmp(&iph->nexthdr, &iph2->nexthdr, |
255 | nlen - offsetof(struct ipv6hdr, nexthdr))) { | |
256 | NAPI_GRO_CB(p)->same_flow = 0; | |
257 | continue; | |
258 | } | |
259 | /* flush if Traffic Class fields are different */ | |
260 | NAPI_GRO_CB(p)->flush |= !!(first_word & htonl(0x0FF00000)); | |
261 | NAPI_GRO_CB(p)->flush |= flush; | |
262 | } | |
263 | ||
264 | NAPI_GRO_CB(skb)->flush |= flush; | |
265 | ||
4de462ab | 266 | skb_gro_postpull_rcsum(skb, iph, nlen); |
d1da932e | 267 | |
f191a1d1 | 268 | pp = ops->callbacks.gro_receive(head, skb); |
d1da932e | 269 | |
d1da932e VY |
270 | out_unlock: |
271 | rcu_read_unlock(); | |
272 | ||
273 | out: | |
274 | NAPI_GRO_CB(skb)->flush |= flush; | |
275 | ||
276 | return pp; | |
277 | } | |
278 | ||
299603e8 | 279 | static int ipv6_gro_complete(struct sk_buff *skb, int nhoff) |
d1da932e VY |
280 | { |
281 | const struct net_offload *ops; | |
299603e8 | 282 | struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + nhoff); |
d1da932e VY |
283 | int err = -ENOSYS; |
284 | ||
299603e8 | 285 | iph->payload_len = htons(skb->len - nhoff - sizeof(*iph)); |
d1da932e VY |
286 | |
287 | rcu_read_lock(); | |
299603e8 JC |
288 | |
289 | nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops); | |
f191a1d1 | 290 | if (WARN_ON(!ops || !ops->callbacks.gro_complete)) |
d1da932e VY |
291 | goto out_unlock; |
292 | ||
299603e8 | 293 | err = ops->callbacks.gro_complete(skb, nhoff); |
d1da932e VY |
294 | |
295 | out_unlock: | |
296 | rcu_read_unlock(); | |
297 | ||
298 | return err; | |
299 | } | |
300 | ||
301 | static struct packet_offload ipv6_packet_offload __read_mostly = { | |
302 | .type = cpu_to_be16(ETH_P_IPV6), | |
f191a1d1 VY |
303 | .callbacks = { |
304 | .gso_send_check = ipv6_gso_send_check, | |
305 | .gso_segment = ipv6_gso_segment, | |
306 | .gro_receive = ipv6_gro_receive, | |
307 | .gro_complete = ipv6_gro_complete, | |
308 | }, | |
d1da932e VY |
309 | }; |
310 | ||
61c1db7f ED |
311 | static const struct net_offload sit_offload = { |
312 | .callbacks = { | |
313 | .gso_send_check = ipv6_gso_send_check, | |
314 | .gso_segment = ipv6_gso_segment, | |
315 | }, | |
316 | }; | |
317 | ||
c6b641a4 | 318 | static int __init ipv6_offload_init(void) |
d1da932e | 319 | { |
c6b641a4 VY |
320 | |
321 | if (tcpv6_offload_init() < 0) | |
322 | pr_crit("%s: Cannot add TCP protocol offload\n", __func__); | |
323 | if (udp_offload_init() < 0) | |
324 | pr_crit("%s: Cannot add UDP protocol offload\n", __func__); | |
325 | if (ipv6_exthdrs_offload_init() < 0) | |
326 | pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__); | |
327 | ||
d1da932e | 328 | dev_add_offload(&ipv6_packet_offload); |
61c1db7f ED |
329 | |
330 | inet_add_offload(&sit_offload, IPPROTO_IPV6); | |
331 | ||
c6b641a4 | 332 | return 0; |
d1da932e VY |
333 | } |
334 | ||
c6b641a4 | 335 | fs_initcall(ipv6_offload_init); |