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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; | |
66 | u8 *prevhdr; | |
67 | int offset = 0; | |
91a48a2e | 68 | bool encap, udpfrag; |
d3e5e006 | 69 | int nhoff; |
d1da932e | 70 | |
d1da932e VY |
71 | if (unlikely(skb_shinfo(skb)->gso_type & |
72 | ~(SKB_GSO_UDP | | |
73 | SKB_GSO_DODGY | | |
74 | SKB_GSO_TCP_ECN | | |
68c33163 | 75 | SKB_GSO_GRE | |
4749c09c | 76 | SKB_GSO_GRE_CSUM | |
cb32f511 | 77 | SKB_GSO_IPIP | |
61c1db7f | 78 | SKB_GSO_SIT | |
73136267 | 79 | SKB_GSO_UDP_TUNNEL | |
0f4f4ffa | 80 | SKB_GSO_UDP_TUNNEL_CSUM | |
0d89d203 | 81 | SKB_GSO_MPLS | |
d1da932e VY |
82 | SKB_GSO_TCPV6 | |
83 | 0))) | |
84 | goto out; | |
85 | ||
d3e5e006 ED |
86 | skb_reset_network_header(skb); |
87 | nhoff = skb_network_header(skb) - skb_mac_header(skb); | |
d1da932e VY |
88 | if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h)))) |
89 | goto out; | |
90 | ||
91a48a2e HFS |
91 | encap = SKB_GSO_CB(skb)->encap_level > 0; |
92 | if (encap) | |
d3e5e006 ED |
93 | features = skb->dev->hw_enc_features & netif_skb_features(skb); |
94 | SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h); | |
95 | ||
d1da932e VY |
96 | ipv6h = ipv6_hdr(skb); |
97 | __skb_pull(skb, sizeof(*ipv6h)); | |
98 | segs = ERR_PTR(-EPROTONOSUPPORT); | |
99 | ||
100 | proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr); | |
b917eb15 | 101 | |
91a48a2e HFS |
102 | if (skb->encapsulation && |
103 | skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP)) | |
104 | udpfrag = proto == IPPROTO_UDP && encap; | |
105 | else | |
106 | udpfrag = proto == IPPROTO_UDP && !skb->encapsulation; | |
107 | ||
d1da932e | 108 | ops = rcu_dereference(inet6_offloads[proto]); |
f191a1d1 | 109 | if (likely(ops && ops->callbacks.gso_segment)) { |
d1da932e | 110 | skb_reset_transport_header(skb); |
f191a1d1 | 111 | segs = ops->callbacks.gso_segment(skb, features); |
d1da932e | 112 | } |
d1da932e VY |
113 | |
114 | if (IS_ERR(segs)) | |
115 | goto out; | |
116 | ||
117 | for (skb = segs; skb; skb = skb->next) { | |
d3e5e006 ED |
118 | ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff); |
119 | ipv6h->payload_len = htons(skb->len - nhoff - sizeof(*ipv6h)); | |
d3e5e006 ED |
120 | skb->network_header = (u8 *)ipv6h - skb->head; |
121 | ||
91a48a2e | 122 | if (udpfrag) { |
d1da932e | 123 | unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr); |
d3e5e006 | 124 | fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen); |
d1da932e VY |
125 | fptr->frag_off = htons(offset); |
126 | if (skb->next != NULL) | |
127 | fptr->frag_off |= htons(IP6_MF); | |
128 | offset += (ntohs(ipv6h->payload_len) - | |
129 | sizeof(struct frag_hdr)); | |
130 | } | |
91a48a2e HFS |
131 | if (encap) |
132 | skb_reset_inner_headers(skb); | |
d1da932e VY |
133 | } |
134 | ||
135 | out: | |
136 | return segs; | |
137 | } | |
138 | ||
299603e8 JC |
139 | /* Return the total length of all the extension hdrs, following the same |
140 | * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs. | |
141 | */ | |
142 | static int ipv6_exthdrs_len(struct ipv6hdr *iph, | |
143 | const struct net_offload **opps) | |
144 | { | |
810c23a3 JC |
145 | struct ipv6_opt_hdr *opth = (void *)iph; |
146 | int len = 0, proto, optlen = sizeof(*iph); | |
299603e8 JC |
147 | |
148 | proto = iph->nexthdr; | |
149 | for (;;) { | |
150 | if (proto != NEXTHDR_HOP) { | |
151 | *opps = rcu_dereference(inet6_offloads[proto]); | |
152 | if (unlikely(!(*opps))) | |
153 | break; | |
154 | if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR)) | |
155 | break; | |
156 | } | |
810c23a3 JC |
157 | opth = (void *)opth + optlen; |
158 | optlen = ipv6_optlen(opth); | |
299603e8 JC |
159 | len += optlen; |
160 | proto = opth->nexthdr; | |
161 | } | |
162 | return len; | |
163 | } | |
164 | ||
d1da932e VY |
165 | static struct sk_buff **ipv6_gro_receive(struct sk_buff **head, |
166 | struct sk_buff *skb) | |
167 | { | |
168 | const struct net_offload *ops; | |
169 | struct sk_buff **pp = NULL; | |
170 | struct sk_buff *p; | |
171 | struct ipv6hdr *iph; | |
172 | unsigned int nlen; | |
173 | unsigned int hlen; | |
174 | unsigned int off; | |
bf5a755f | 175 | u16 flush = 1; |
d1da932e | 176 | int proto; |
d1da932e VY |
177 | |
178 | off = skb_gro_offset(skb); | |
179 | hlen = off + sizeof(*iph); | |
180 | iph = skb_gro_header_fast(skb, off); | |
181 | if (skb_gro_header_hard(skb, hlen)) { | |
182 | iph = skb_gro_header_slow(skb, hlen, off); | |
183 | if (unlikely(!iph)) | |
184 | goto out; | |
185 | } | |
186 | ||
299603e8 | 187 | skb_set_network_header(skb, off); |
d1da932e VY |
188 | skb_gro_pull(skb, sizeof(*iph)); |
189 | skb_set_transport_header(skb, skb_gro_offset(skb)); | |
190 | ||
191 | flush += ntohs(iph->payload_len) != skb_gro_len(skb); | |
192 | ||
193 | rcu_read_lock(); | |
194 | proto = iph->nexthdr; | |
195 | ops = rcu_dereference(inet6_offloads[proto]); | |
f191a1d1 | 196 | if (!ops || !ops->callbacks.gro_receive) { |
d1da932e VY |
197 | __pskb_pull(skb, skb_gro_offset(skb)); |
198 | proto = ipv6_gso_pull_exthdrs(skb, proto); | |
199 | skb_gro_pull(skb, -skb_transport_offset(skb)); | |
200 | skb_reset_transport_header(skb); | |
201 | __skb_push(skb, skb_gro_offset(skb)); | |
202 | ||
203 | ops = rcu_dereference(inet6_offloads[proto]); | |
f191a1d1 | 204 | if (!ops || !ops->callbacks.gro_receive) |
d1da932e VY |
205 | goto out_unlock; |
206 | ||
207 | iph = ipv6_hdr(skb); | |
208 | } | |
209 | ||
210 | NAPI_GRO_CB(skb)->proto = proto; | |
211 | ||
212 | flush--; | |
213 | nlen = skb_network_header_len(skb); | |
214 | ||
215 | for (p = *head; p; p = p->next) { | |
216 | const struct ipv6hdr *iph2; | |
217 | __be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */ | |
218 | ||
219 | if (!NAPI_GRO_CB(p)->same_flow) | |
220 | continue; | |
221 | ||
299603e8 | 222 | iph2 = (struct ipv6hdr *)(p->data + off); |
67ba4152 | 223 | first_word = *(__be32 *)iph ^ *(__be32 *)iph2; |
d1da932e | 224 | |
299603e8 JC |
225 | /* All fields must match except length and Traffic Class. |
226 | * XXX skbs on the gro_list have all been parsed and pulled | |
227 | * already so we don't need to compare nlen | |
228 | * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops))) | |
229 | * memcmp() alone below is suffcient, right? | |
230 | */ | |
231 | if ((first_word & htonl(0xF00FFFFF)) || | |
d1da932e VY |
232 | memcmp(&iph->nexthdr, &iph2->nexthdr, |
233 | nlen - offsetof(struct ipv6hdr, nexthdr))) { | |
234 | NAPI_GRO_CB(p)->same_flow = 0; | |
235 | continue; | |
236 | } | |
237 | /* flush if Traffic Class fields are different */ | |
238 | NAPI_GRO_CB(p)->flush |= !!(first_word & htonl(0x0FF00000)); | |
239 | NAPI_GRO_CB(p)->flush |= flush; | |
03d56daa TH |
240 | |
241 | /* Clear flush_id, there's really no concept of ID in IPv6. */ | |
242 | NAPI_GRO_CB(p)->flush_id = 0; | |
d1da932e VY |
243 | } |
244 | ||
245 | NAPI_GRO_CB(skb)->flush |= flush; | |
246 | ||
4de462ab | 247 | skb_gro_postpull_rcsum(skb, iph, nlen); |
d1da932e | 248 | |
f191a1d1 | 249 | pp = ops->callbacks.gro_receive(head, skb); |
d1da932e | 250 | |
d1da932e VY |
251 | out_unlock: |
252 | rcu_read_unlock(); | |
253 | ||
254 | out: | |
255 | NAPI_GRO_CB(skb)->flush |= flush; | |
256 | ||
257 | return pp; | |
258 | } | |
259 | ||
299603e8 | 260 | static int ipv6_gro_complete(struct sk_buff *skb, int nhoff) |
d1da932e VY |
261 | { |
262 | const struct net_offload *ops; | |
299603e8 | 263 | struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + nhoff); |
d1da932e VY |
264 | int err = -ENOSYS; |
265 | ||
299603e8 | 266 | iph->payload_len = htons(skb->len - nhoff - sizeof(*iph)); |
d1da932e VY |
267 | |
268 | rcu_read_lock(); | |
299603e8 JC |
269 | |
270 | nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops); | |
f191a1d1 | 271 | if (WARN_ON(!ops || !ops->callbacks.gro_complete)) |
d1da932e VY |
272 | goto out_unlock; |
273 | ||
299603e8 | 274 | err = ops->callbacks.gro_complete(skb, nhoff); |
d1da932e VY |
275 | |
276 | out_unlock: | |
277 | rcu_read_unlock(); | |
278 | ||
279 | return err; | |
280 | } | |
281 | ||
282 | static struct packet_offload ipv6_packet_offload __read_mostly = { | |
283 | .type = cpu_to_be16(ETH_P_IPV6), | |
f191a1d1 | 284 | .callbacks = { |
f191a1d1 VY |
285 | .gso_segment = ipv6_gso_segment, |
286 | .gro_receive = ipv6_gro_receive, | |
287 | .gro_complete = ipv6_gro_complete, | |
288 | }, | |
d1da932e VY |
289 | }; |
290 | ||
61c1db7f ED |
291 | static const struct net_offload sit_offload = { |
292 | .callbacks = { | |
61c1db7f | 293 | .gso_segment = ipv6_gso_segment, |
19424e05 TH |
294 | .gro_receive = ipv6_gro_receive, |
295 | .gro_complete = ipv6_gro_complete, | |
61c1db7f ED |
296 | }, |
297 | }; | |
298 | ||
c6b641a4 | 299 | static int __init ipv6_offload_init(void) |
d1da932e | 300 | { |
c6b641a4 VY |
301 | |
302 | if (tcpv6_offload_init() < 0) | |
303 | pr_crit("%s: Cannot add TCP protocol offload\n", __func__); | |
304 | if (udp_offload_init() < 0) | |
305 | pr_crit("%s: Cannot add UDP protocol offload\n", __func__); | |
306 | if (ipv6_exthdrs_offload_init() < 0) | |
307 | pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__); | |
308 | ||
d1da932e | 309 | dev_add_offload(&ipv6_packet_offload); |
61c1db7f ED |
310 | |
311 | inet_add_offload(&sit_offload, IPPROTO_IPV6); | |
312 | ||
c6b641a4 | 313 | return 0; |
d1da932e VY |
314 | } |
315 | ||
c6b641a4 | 316 | fs_initcall(ipv6_offload_init); |