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Commit | Line | Data |
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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 | ||
fc6fb41c | 49 | opth = (void *)skb->data; |
d1da932e VY |
50 | proto = opth->nexthdr; |
51 | __skb_pull(skb, len); | |
52 | } | |
53 | ||
54 | return proto; | |
55 | } | |
56 | ||
d1da932e VY |
57 | static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, |
58 | netdev_features_t features) | |
59 | { | |
60 | struct sk_buff *segs = ERR_PTR(-EINVAL); | |
61 | struct ipv6hdr *ipv6h; | |
62 | const struct net_offload *ops; | |
63 | int proto; | |
64 | struct frag_hdr *fptr; | |
65 | unsigned int unfrag_ip6hlen; | |
802ab55a | 66 | unsigned int payload_len; |
d1da932e VY |
67 | u8 *prevhdr; |
68 | int offset = 0; | |
91a48a2e | 69 | bool encap, udpfrag; |
d3e5e006 | 70 | int nhoff; |
d1da932e | 71 | |
d3e5e006 ED |
72 | skb_reset_network_header(skb); |
73 | nhoff = skb_network_header(skb) - skb_mac_header(skb); | |
d1da932e VY |
74 | if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h)))) |
75 | goto out; | |
76 | ||
91a48a2e HFS |
77 | encap = SKB_GSO_CB(skb)->encap_level > 0; |
78 | if (encap) | |
1e16aa3d | 79 | features &= skb->dev->hw_enc_features; |
d3e5e006 ED |
80 | SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h); |
81 | ||
d1da932e VY |
82 | ipv6h = ipv6_hdr(skb); |
83 | __skb_pull(skb, sizeof(*ipv6h)); | |
84 | segs = ERR_PTR(-EPROTONOSUPPORT); | |
85 | ||
86 | proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr); | |
b917eb15 | 87 | |
91a48a2e | 88 | if (skb->encapsulation && |
7e13318d | 89 | skb_shinfo(skb)->gso_type & (SKB_GSO_IPXIP4 | SKB_GSO_IPXIP6)) |
91a48a2e HFS |
90 | udpfrag = proto == IPPROTO_UDP && encap; |
91 | else | |
92 | udpfrag = proto == IPPROTO_UDP && !skb->encapsulation; | |
93 | ||
d1da932e | 94 | ops = rcu_dereference(inet6_offloads[proto]); |
f191a1d1 | 95 | if (likely(ops && ops->callbacks.gso_segment)) { |
d1da932e | 96 | skb_reset_transport_header(skb); |
f191a1d1 | 97 | segs = ops->callbacks.gso_segment(skb, features); |
d1da932e | 98 | } |
d1da932e VY |
99 | |
100 | if (IS_ERR(segs)) | |
101 | goto out; | |
102 | ||
103 | for (skb = segs; skb; skb = skb->next) { | |
d3e5e006 | 104 | ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff); |
802ab55a AD |
105 | if (skb_is_gso(skb)) |
106 | payload_len = skb_shinfo(skb)->gso_size + | |
107 | SKB_GSO_CB(skb)->data_offset + | |
108 | skb->head - (unsigned char *)(ipv6h + 1); | |
109 | else | |
110 | payload_len = skb->len - nhoff - sizeof(*ipv6h); | |
111 | ipv6h->payload_len = htons(payload_len); | |
d3e5e006 ED |
112 | skb->network_header = (u8 *)ipv6h - skb->head; |
113 | ||
91a48a2e | 114 | if (udpfrag) { |
d1da932e | 115 | unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr); |
d3e5e006 | 116 | fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen); |
d1da932e | 117 | fptr->frag_off = htons(offset); |
53b24b8f | 118 | if (skb->next) |
d1da932e VY |
119 | fptr->frag_off |= htons(IP6_MF); |
120 | offset += (ntohs(ipv6h->payload_len) - | |
121 | sizeof(struct frag_hdr)); | |
122 | } | |
91a48a2e HFS |
123 | if (encap) |
124 | skb_reset_inner_headers(skb); | |
d1da932e VY |
125 | } |
126 | ||
127 | out: | |
128 | return segs; | |
129 | } | |
130 | ||
299603e8 JC |
131 | /* Return the total length of all the extension hdrs, following the same |
132 | * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs. | |
133 | */ | |
134 | static int ipv6_exthdrs_len(struct ipv6hdr *iph, | |
135 | const struct net_offload **opps) | |
136 | { | |
810c23a3 JC |
137 | struct ipv6_opt_hdr *opth = (void *)iph; |
138 | int len = 0, proto, optlen = sizeof(*iph); | |
299603e8 JC |
139 | |
140 | proto = iph->nexthdr; | |
141 | for (;;) { | |
142 | if (proto != NEXTHDR_HOP) { | |
143 | *opps = rcu_dereference(inet6_offloads[proto]); | |
144 | if (unlikely(!(*opps))) | |
145 | break; | |
146 | if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR)) | |
147 | break; | |
148 | } | |
810c23a3 JC |
149 | opth = (void *)opth + optlen; |
150 | optlen = ipv6_optlen(opth); | |
299603e8 JC |
151 | len += optlen; |
152 | proto = opth->nexthdr; | |
153 | } | |
154 | return len; | |
155 | } | |
156 | ||
d1da932e VY |
157 | static struct sk_buff **ipv6_gro_receive(struct sk_buff **head, |
158 | struct sk_buff *skb) | |
159 | { | |
160 | const struct net_offload *ops; | |
161 | struct sk_buff **pp = NULL; | |
162 | struct sk_buff *p; | |
163 | struct ipv6hdr *iph; | |
164 | unsigned int nlen; | |
165 | unsigned int hlen; | |
166 | unsigned int off; | |
bf5a755f | 167 | u16 flush = 1; |
d1da932e | 168 | int proto; |
d1da932e VY |
169 | |
170 | off = skb_gro_offset(skb); | |
171 | hlen = off + sizeof(*iph); | |
172 | iph = skb_gro_header_fast(skb, off); | |
173 | if (skb_gro_header_hard(skb, hlen)) { | |
174 | iph = skb_gro_header_slow(skb, hlen, off); | |
175 | if (unlikely(!iph)) | |
176 | goto out; | |
177 | } | |
178 | ||
299603e8 | 179 | skb_set_network_header(skb, off); |
d1da932e VY |
180 | skb_gro_pull(skb, sizeof(*iph)); |
181 | skb_set_transport_header(skb, skb_gro_offset(skb)); | |
182 | ||
183 | flush += ntohs(iph->payload_len) != skb_gro_len(skb); | |
184 | ||
185 | rcu_read_lock(); | |
186 | proto = iph->nexthdr; | |
187 | ops = rcu_dereference(inet6_offloads[proto]); | |
f191a1d1 | 188 | if (!ops || !ops->callbacks.gro_receive) { |
d1da932e VY |
189 | __pskb_pull(skb, skb_gro_offset(skb)); |
190 | proto = ipv6_gso_pull_exthdrs(skb, proto); | |
191 | skb_gro_pull(skb, -skb_transport_offset(skb)); | |
192 | skb_reset_transport_header(skb); | |
193 | __skb_push(skb, skb_gro_offset(skb)); | |
194 | ||
195 | ops = rcu_dereference(inet6_offloads[proto]); | |
f191a1d1 | 196 | if (!ops || !ops->callbacks.gro_receive) |
d1da932e VY |
197 | goto out_unlock; |
198 | ||
199 | iph = ipv6_hdr(skb); | |
200 | } | |
201 | ||
202 | NAPI_GRO_CB(skb)->proto = proto; | |
203 | ||
204 | flush--; | |
205 | nlen = skb_network_header_len(skb); | |
206 | ||
207 | for (p = *head; p; p = p->next) { | |
208 | const struct ipv6hdr *iph2; | |
209 | __be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */ | |
210 | ||
211 | if (!NAPI_GRO_CB(p)->same_flow) | |
212 | continue; | |
213 | ||
299603e8 | 214 | iph2 = (struct ipv6hdr *)(p->data + off); |
67ba4152 | 215 | first_word = *(__be32 *)iph ^ *(__be32 *)iph2; |
d1da932e | 216 | |
299603e8 JC |
217 | /* All fields must match except length and Traffic Class. |
218 | * XXX skbs on the gro_list have all been parsed and pulled | |
219 | * already so we don't need to compare nlen | |
220 | * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops))) | |
221 | * memcmp() alone below is suffcient, right? | |
222 | */ | |
223 | if ((first_word & htonl(0xF00FFFFF)) || | |
d1da932e VY |
224 | memcmp(&iph->nexthdr, &iph2->nexthdr, |
225 | nlen - offsetof(struct ipv6hdr, nexthdr))) { | |
226 | NAPI_GRO_CB(p)->same_flow = 0; | |
227 | continue; | |
228 | } | |
229 | /* flush if Traffic Class fields are different */ | |
230 | NAPI_GRO_CB(p)->flush |= !!(first_word & htonl(0x0FF00000)); | |
231 | NAPI_GRO_CB(p)->flush |= flush; | |
03d56daa | 232 | |
1530545e AD |
233 | /* If the previous IP ID value was based on an atomic |
234 | * datagram we can overwrite the value and ignore it. | |
235 | */ | |
236 | if (NAPI_GRO_CB(skb)->is_atomic) | |
237 | NAPI_GRO_CB(p)->flush_id = 0; | |
d1da932e VY |
238 | } |
239 | ||
1530545e | 240 | NAPI_GRO_CB(skb)->is_atomic = true; |
d1da932e VY |
241 | NAPI_GRO_CB(skb)->flush |= flush; |
242 | ||
4de462ab | 243 | skb_gro_postpull_rcsum(skb, iph, nlen); |
d1da932e | 244 | |
f191a1d1 | 245 | pp = ops->callbacks.gro_receive(head, skb); |
d1da932e | 246 | |
d1da932e VY |
247 | out_unlock: |
248 | rcu_read_unlock(); | |
249 | ||
250 | out: | |
251 | NAPI_GRO_CB(skb)->flush |= flush; | |
252 | ||
253 | return pp; | |
254 | } | |
255 | ||
fac8e0f5 JG |
256 | static struct sk_buff **sit_gro_receive(struct sk_buff **head, |
257 | struct sk_buff *skb) | |
258 | { | |
259 | if (NAPI_GRO_CB(skb)->encap_mark) { | |
260 | NAPI_GRO_CB(skb)->flush = 1; | |
261 | return NULL; | |
262 | } | |
263 | ||
264 | NAPI_GRO_CB(skb)->encap_mark = 1; | |
265 | ||
266 | return ipv6_gro_receive(head, skb); | |
267 | } | |
268 | ||
299603e8 | 269 | static int ipv6_gro_complete(struct sk_buff *skb, int nhoff) |
d1da932e VY |
270 | { |
271 | const struct net_offload *ops; | |
299603e8 | 272 | struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + nhoff); |
d1da932e VY |
273 | int err = -ENOSYS; |
274 | ||
feec0cb3 ED |
275 | if (skb->encapsulation) |
276 | skb_set_inner_network_header(skb, nhoff); | |
277 | ||
299603e8 | 278 | iph->payload_len = htons(skb->len - nhoff - sizeof(*iph)); |
d1da932e VY |
279 | |
280 | rcu_read_lock(); | |
299603e8 JC |
281 | |
282 | nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops); | |
f191a1d1 | 283 | if (WARN_ON(!ops || !ops->callbacks.gro_complete)) |
d1da932e VY |
284 | goto out_unlock; |
285 | ||
299603e8 | 286 | err = ops->callbacks.gro_complete(skb, nhoff); |
d1da932e VY |
287 | |
288 | out_unlock: | |
289 | rcu_read_unlock(); | |
290 | ||
291 | return err; | |
292 | } | |
293 | ||
feec0cb3 ED |
294 | static int sit_gro_complete(struct sk_buff *skb, int nhoff) |
295 | { | |
296 | skb->encapsulation = 1; | |
7e13318d | 297 | skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4; |
feec0cb3 ED |
298 | return ipv6_gro_complete(skb, nhoff); |
299 | } | |
300 | ||
d1da932e VY |
301 | static struct packet_offload ipv6_packet_offload __read_mostly = { |
302 | .type = cpu_to_be16(ETH_P_IPV6), | |
f191a1d1 | 303 | .callbacks = { |
f191a1d1 VY |
304 | .gso_segment = ipv6_gso_segment, |
305 | .gro_receive = ipv6_gro_receive, | |
306 | .gro_complete = ipv6_gro_complete, | |
307 | }, | |
d1da932e VY |
308 | }; |
309 | ||
61c1db7f ED |
310 | static const struct net_offload sit_offload = { |
311 | .callbacks = { | |
61c1db7f | 312 | .gso_segment = ipv6_gso_segment, |
fac8e0f5 | 313 | .gro_receive = sit_gro_receive, |
feec0cb3 | 314 | .gro_complete = sit_gro_complete, |
61c1db7f ED |
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__); | |
c6b641a4 VY |
323 | if (ipv6_exthdrs_offload_init() < 0) |
324 | pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__); | |
325 | ||
d1da932e | 326 | dev_add_offload(&ipv6_packet_offload); |
61c1db7f ED |
327 | |
328 | inet_add_offload(&sit_offload, IPPROTO_IPV6); | |
329 | ||
c6b641a4 | 330 | return 0; |
d1da932e VY |
331 | } |
332 | ||
c6b641a4 | 333 | fs_initcall(ipv6_offload_init); |