Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * IPV6 GSO/GRO offload support
4 * Linux INET6 implementation
5 */
6
7#include <linux/kernel.h>
8#include <linux/socket.h>
9#include <linux/netdevice.h>
10#include <linux/skbuff.h>
11#include <linux/printk.h>
12
13#include <net/protocol.h>
14#include <net/ipv6.h>
15#include <net/inet_common.h>
16#include <net/tcp.h>
17#include <net/udp.h>
18#include <net/gro.h>
19#include <net/gso.h>
20
21#include "ip6_offload.h"
22
23/* All GRO functions are always builtin, except UDP over ipv6, which lays in
24 * ipv6 module, as it depends on UDPv6 lookup function, so we need special care
25 * when ipv6 is built as a module
26 */
27#if IS_BUILTIN(CONFIG_IPV6)
28#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_2(f, f2, f1, __VA_ARGS__)
29#else
30#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__)
31#endif
32
33#define indirect_call_gro_receive_l4(f2, f1, cb, head, skb) \
34({ \
35 unlikely(gro_recursion_inc_test(skb)) ? \
36 NAPI_GRO_CB(skb)->flush |= 1, NULL : \
37 INDIRECT_CALL_L4(cb, f2, f1, head, skb); \
38})
39
40static int ipv6_gro_pull_exthdrs(struct sk_buff *skb, int off, int proto)
41{
42 const struct net_offload *ops = NULL;
43 struct ipv6_opt_hdr *opth;
44
45 for (;;) {
46 int len;
47
48 ops = rcu_dereference(inet6_offloads[proto]);
49
50 if (unlikely(!ops))
51 break;
52
53 if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
54 break;
55
56 opth = skb_gro_header(skb, off + sizeof(*opth), off);
57 if (unlikely(!opth))
58 break;
59
60 len = ipv6_optlen(opth);
61
62 opth = skb_gro_header(skb, off + len, off);
63 if (unlikely(!opth))
64 break;
65 proto = opth->nexthdr;
66
67 off += len;
68 }
69
70 skb_gro_pull(skb, off - skb_gro_receive_network_offset(skb));
71 return proto;
72}
73
74static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
75{
76 const struct net_offload *ops = NULL;
77
78 for (;;) {
79 struct ipv6_opt_hdr *opth;
80 int len;
81
82 ops = rcu_dereference(inet6_offloads[proto]);
83
84 if (unlikely(!ops))
85 break;
86
87 if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
88 break;
89
90 if (unlikely(!pskb_may_pull(skb, 8)))
91 break;
92
93 opth = (void *)skb->data;
94 len = ipv6_optlen(opth);
95
96 if (unlikely(!pskb_may_pull(skb, len)))
97 break;
98
99 opth = (void *)skb->data;
100 proto = opth->nexthdr;
101 __skb_pull(skb, len);
102 }
103
104 return proto;
105}
106
107static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
108 netdev_features_t features)
109{
110 struct sk_buff *segs = ERR_PTR(-EINVAL);
111 struct ipv6hdr *ipv6h;
112 const struct net_offload *ops;
113 int proto, err;
114 struct frag_hdr *fptr;
115 unsigned int payload_len;
116 u8 *prevhdr;
117 int offset = 0;
118 bool encap, udpfrag;
119 int nhoff;
120 bool gso_partial;
121
122 skb_reset_network_header(skb);
123 err = ipv6_hopopt_jumbo_remove(skb);
124 if (err)
125 return ERR_PTR(err);
126 nhoff = skb_network_header(skb) - skb_mac_header(skb);
127 if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
128 goto out;
129
130 encap = SKB_GSO_CB(skb)->encap_level > 0;
131 if (encap)
132 features &= skb->dev->hw_enc_features;
133 SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
134
135 ipv6h = ipv6_hdr(skb);
136 __skb_pull(skb, sizeof(*ipv6h));
137 segs = ERR_PTR(-EPROTONOSUPPORT);
138
139 proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
140
141 if (skb->encapsulation &&
142 skb_shinfo(skb)->gso_type & (SKB_GSO_IPXIP4 | SKB_GSO_IPXIP6))
143 udpfrag = proto == IPPROTO_UDP && encap &&
144 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
145 else
146 udpfrag = proto == IPPROTO_UDP && !skb->encapsulation &&
147 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
148
149 ops = rcu_dereference(inet6_offloads[proto]);
150 if (likely(ops && ops->callbacks.gso_segment)) {
151 skb_reset_transport_header(skb);
152 segs = ops->callbacks.gso_segment(skb, features);
153 if (!segs)
154 skb->network_header = skb_mac_header(skb) + nhoff - skb->head;
155 }
156
157 if (IS_ERR_OR_NULL(segs))
158 goto out;
159
160 gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
161
162 for (skb = segs; skb; skb = skb->next) {
163 ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
164 if (gso_partial && skb_is_gso(skb))
165 payload_len = skb_shinfo(skb)->gso_size +
166 SKB_GSO_CB(skb)->data_offset +
167 skb->head - (unsigned char *)(ipv6h + 1);
168 else
169 payload_len = skb->len - nhoff - sizeof(*ipv6h);
170 ipv6h->payload_len = htons(payload_len);
171 skb->network_header = (u8 *)ipv6h - skb->head;
172 skb_reset_mac_len(skb);
173
174 if (udpfrag) {
175 int err = ip6_find_1stfragopt(skb, &prevhdr);
176 if (err < 0) {
177 kfree_skb_list(segs);
178 return ERR_PTR(err);
179 }
180 fptr = (struct frag_hdr *)((u8 *)ipv6h + err);
181 fptr->frag_off = htons(offset);
182 if (skb->next)
183 fptr->frag_off |= htons(IP6_MF);
184 offset += (ntohs(ipv6h->payload_len) -
185 sizeof(struct frag_hdr));
186 }
187 if (encap)
188 skb_reset_inner_headers(skb);
189 }
190
191out:
192 return segs;
193}
194
195/* Return the total length of all the extension hdrs, following the same
196 * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
197 */
198static int ipv6_exthdrs_len(struct ipv6hdr *iph,
199 const struct net_offload **opps)
200{
201 struct ipv6_opt_hdr *opth = (void *)iph;
202 int len = 0, proto, optlen = sizeof(*iph);
203
204 proto = iph->nexthdr;
205 for (;;) {
206 *opps = rcu_dereference(inet6_offloads[proto]);
207 if (unlikely(!(*opps)))
208 break;
209 if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
210 break;
211
212 opth = (void *)opth + optlen;
213 optlen = ipv6_optlen(opth);
214 len += optlen;
215 proto = opth->nexthdr;
216 }
217 return len;
218}
219
220INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
221 struct sk_buff *skb)
222{
223 const struct net_offload *ops;
224 struct sk_buff *pp = NULL;
225 struct sk_buff *p;
226 struct ipv6hdr *iph;
227 unsigned int nlen;
228 unsigned int hlen;
229 unsigned int off;
230 u16 flush = 1;
231 int proto;
232
233 off = skb_gro_offset(skb);
234 hlen = off + sizeof(*iph);
235 iph = skb_gro_header(skb, hlen, off);
236 if (unlikely(!iph))
237 goto out;
238
239 NAPI_GRO_CB(skb)->network_offsets[NAPI_GRO_CB(skb)->encap_mark] = off;
240
241 flush += ntohs(iph->payload_len) != skb->len - hlen;
242
243 proto = iph->nexthdr;
244 ops = rcu_dereference(inet6_offloads[proto]);
245 if (!ops || !ops->callbacks.gro_receive) {
246 proto = ipv6_gro_pull_exthdrs(skb, hlen, proto);
247
248 ops = rcu_dereference(inet6_offloads[proto]);
249 if (!ops || !ops->callbacks.gro_receive)
250 goto out;
251
252 iph = skb_gro_network_header(skb);
253 } else {
254 skb_gro_pull(skb, sizeof(*iph));
255 }
256
257 skb_set_transport_header(skb, skb_gro_offset(skb));
258
259 NAPI_GRO_CB(skb)->proto = proto;
260
261 flush--;
262 nlen = skb_gro_offset(skb) - off;
263
264 list_for_each_entry(p, head, list) {
265 const struct ipv6hdr *iph2;
266 __be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
267
268 if (!NAPI_GRO_CB(p)->same_flow)
269 continue;
270
271 iph2 = (struct ipv6hdr *)(p->data + off);
272 first_word = *(__be32 *)iph ^ *(__be32 *)iph2;
273
274 /* All fields must match except length and Traffic Class.
275 * XXX skbs on the gro_list have all been parsed and pulled
276 * already so we don't need to compare nlen
277 * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
278 * memcmp() alone below is sufficient, right?
279 */
280 if ((first_word & htonl(0xF00FFFFF)) ||
281 !ipv6_addr_equal(&iph->saddr, &iph2->saddr) ||
282 !ipv6_addr_equal(&iph->daddr, &iph2->daddr) ||
283 iph->nexthdr != iph2->nexthdr) {
284not_same_flow:
285 NAPI_GRO_CB(p)->same_flow = 0;
286 continue;
287 }
288 if (unlikely(nlen > sizeof(struct ipv6hdr))) {
289 if (memcmp(iph + 1, iph2 + 1,
290 nlen - sizeof(struct ipv6hdr)))
291 goto not_same_flow;
292 }
293 }
294
295 NAPI_GRO_CB(skb)->flush |= flush;
296
297 skb_gro_postpull_rcsum(skb, iph, nlen);
298
299 pp = indirect_call_gro_receive_l4(tcp6_gro_receive, udp6_gro_receive,
300 ops->callbacks.gro_receive, head, skb);
301
302out:
303 skb_gro_flush_final(skb, pp, flush);
304
305 return pp;
306}
307
308static struct sk_buff *sit_ip6ip6_gro_receive(struct list_head *head,
309 struct sk_buff *skb)
310{
311 /* Common GRO receive for SIT and IP6IP6 */
312
313 if (NAPI_GRO_CB(skb)->encap_mark) {
314 NAPI_GRO_CB(skb)->flush = 1;
315 return NULL;
316 }
317
318 NAPI_GRO_CB(skb)->encap_mark = 1;
319
320 return ipv6_gro_receive(head, skb);
321}
322
323static struct sk_buff *ip4ip6_gro_receive(struct list_head *head,
324 struct sk_buff *skb)
325{
326 /* Common GRO receive for SIT and IP6IP6 */
327
328 if (NAPI_GRO_CB(skb)->encap_mark) {
329 NAPI_GRO_CB(skb)->flush = 1;
330 return NULL;
331 }
332
333 NAPI_GRO_CB(skb)->encap_mark = 1;
334
335 return inet_gro_receive(head, skb);
336}
337
338INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
339{
340 const struct net_offload *ops;
341 struct ipv6hdr *iph;
342 int err = -ENOSYS;
343 u32 payload_len;
344
345 if (skb->encapsulation) {
346 skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IPV6));
347 skb_set_inner_network_header(skb, nhoff);
348 }
349
350 payload_len = skb->len - nhoff - sizeof(*iph);
351 if (unlikely(payload_len > IPV6_MAXPLEN)) {
352 struct hop_jumbo_hdr *hop_jumbo;
353 int hoplen = sizeof(*hop_jumbo);
354
355 /* Move network header left */
356 memmove(skb_mac_header(skb) - hoplen, skb_mac_header(skb),
357 skb->transport_header - skb->mac_header);
358 skb->data -= hoplen;
359 skb->len += hoplen;
360 skb->mac_header -= hoplen;
361 skb->network_header -= hoplen;
362 iph = (struct ipv6hdr *)(skb->data + nhoff);
363 hop_jumbo = (struct hop_jumbo_hdr *)(iph + 1);
364
365 /* Build hop-by-hop options */
366 hop_jumbo->nexthdr = iph->nexthdr;
367 hop_jumbo->hdrlen = 0;
368 hop_jumbo->tlv_type = IPV6_TLV_JUMBO;
369 hop_jumbo->tlv_len = 4;
370 hop_jumbo->jumbo_payload_len = htonl(payload_len + hoplen);
371
372 iph->nexthdr = NEXTHDR_HOP;
373 iph->payload_len = 0;
374 } else {
375 iph = (struct ipv6hdr *)(skb->data + nhoff);
376 iph->payload_len = htons(payload_len);
377 }
378
379 nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
380 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
381 goto out;
382
383 err = INDIRECT_CALL_L4(ops->callbacks.gro_complete, tcp6_gro_complete,
384 udp6_gro_complete, skb, nhoff);
385
386out:
387 return err;
388}
389
390static int sit_gro_complete(struct sk_buff *skb, int nhoff)
391{
392 skb->encapsulation = 1;
393 skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
394 return ipv6_gro_complete(skb, nhoff);
395}
396
397static int ip6ip6_gro_complete(struct sk_buff *skb, int nhoff)
398{
399 skb->encapsulation = 1;
400 skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;
401 return ipv6_gro_complete(skb, nhoff);
402}
403
404static int ip4ip6_gro_complete(struct sk_buff *skb, int nhoff)
405{
406 skb->encapsulation = 1;
407 skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;
408 return inet_gro_complete(skb, nhoff);
409}
410
411
412static struct sk_buff *sit_gso_segment(struct sk_buff *skb,
413 netdev_features_t features)
414{
415 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4))
416 return ERR_PTR(-EINVAL);
417
418 return ipv6_gso_segment(skb, features);
419}
420
421static struct sk_buff *ip4ip6_gso_segment(struct sk_buff *skb,
422 netdev_features_t features)
423{
424 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP6))
425 return ERR_PTR(-EINVAL);
426
427 return inet_gso_segment(skb, features);
428}
429
430static struct sk_buff *ip6ip6_gso_segment(struct sk_buff *skb,
431 netdev_features_t features)
432{
433 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP6))
434 return ERR_PTR(-EINVAL);
435
436 return ipv6_gso_segment(skb, features);
437}
438
439static const struct net_offload sit_offload = {
440 .callbacks = {
441 .gso_segment = sit_gso_segment,
442 .gro_receive = sit_ip6ip6_gro_receive,
443 .gro_complete = sit_gro_complete,
444 },
445};
446
447static const struct net_offload ip4ip6_offload = {
448 .callbacks = {
449 .gso_segment = ip4ip6_gso_segment,
450 .gro_receive = ip4ip6_gro_receive,
451 .gro_complete = ip4ip6_gro_complete,
452 },
453};
454
455static const struct net_offload ip6ip6_offload = {
456 .callbacks = {
457 .gso_segment = ip6ip6_gso_segment,
458 .gro_receive = sit_ip6ip6_gro_receive,
459 .gro_complete = ip6ip6_gro_complete,
460 },
461};
462static int __init ipv6_offload_init(void)
463{
464
465 if (tcpv6_offload_init() < 0)
466 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
467 if (ipv6_exthdrs_offload_init() < 0)
468 pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);
469
470 net_hotdata.ipv6_packet_offload = (struct packet_offload) {
471 .type = cpu_to_be16(ETH_P_IPV6),
472 .callbacks = {
473 .gso_segment = ipv6_gso_segment,
474 .gro_receive = ipv6_gro_receive,
475 .gro_complete = ipv6_gro_complete,
476 },
477 };
478 dev_add_offload(&net_hotdata.ipv6_packet_offload);
479
480 inet_add_offload(&sit_offload, IPPROTO_IPV6);
481 inet6_add_offload(&ip6ip6_offload, IPPROTO_IPV6);
482 inet6_add_offload(&ip4ip6_offload, IPPROTO_IPIP);
483
484 return 0;
485}
486
487fs_initcall(ipv6_offload_init);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * IPV6 GSO/GRO offload support
4 * Linux INET6 implementation
5 */
6
7#include <linux/kernel.h>
8#include <linux/socket.h>
9#include <linux/netdevice.h>
10#include <linux/skbuff.h>
11#include <linux/printk.h>
12
13#include <net/protocol.h>
14#include <net/ipv6.h>
15#include <net/inet_common.h>
16#include <net/tcp.h>
17#include <net/udp.h>
18#include <net/gro.h>
19
20#include "ip6_offload.h"
21
22/* All GRO functions are always builtin, except UDP over ipv6, which lays in
23 * ipv6 module, as it depends on UDPv6 lookup function, so we need special care
24 * when ipv6 is built as a module
25 */
26#if IS_BUILTIN(CONFIG_IPV6)
27#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_2(f, f2, f1, __VA_ARGS__)
28#else
29#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__)
30#endif
31
32#define indirect_call_gro_receive_l4(f2, f1, cb, head, skb) \
33({ \
34 unlikely(gro_recursion_inc_test(skb)) ? \
35 NAPI_GRO_CB(skb)->flush |= 1, NULL : \
36 INDIRECT_CALL_L4(cb, f2, f1, head, skb); \
37})
38
39static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
40{
41 const struct net_offload *ops = NULL;
42
43 for (;;) {
44 struct ipv6_opt_hdr *opth;
45 int len;
46
47 if (proto != NEXTHDR_HOP) {
48 ops = rcu_dereference(inet6_offloads[proto]);
49
50 if (unlikely(!ops))
51 break;
52
53 if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
54 break;
55 }
56
57 if (unlikely(!pskb_may_pull(skb, 8)))
58 break;
59
60 opth = (void *)skb->data;
61 len = ipv6_optlen(opth);
62
63 if (unlikely(!pskb_may_pull(skb, len)))
64 break;
65
66 opth = (void *)skb->data;
67 proto = opth->nexthdr;
68 __skb_pull(skb, len);
69 }
70
71 return proto;
72}
73
74static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
75 netdev_features_t features)
76{
77 struct sk_buff *segs = ERR_PTR(-EINVAL);
78 struct ipv6hdr *ipv6h;
79 const struct net_offload *ops;
80 int proto, err;
81 struct frag_hdr *fptr;
82 unsigned int payload_len;
83 u8 *prevhdr;
84 int offset = 0;
85 bool encap, udpfrag;
86 int nhoff;
87 bool gso_partial;
88
89 skb_reset_network_header(skb);
90 err = ipv6_hopopt_jumbo_remove(skb);
91 if (err)
92 return ERR_PTR(err);
93 nhoff = skb_network_header(skb) - skb_mac_header(skb);
94 if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
95 goto out;
96
97 encap = SKB_GSO_CB(skb)->encap_level > 0;
98 if (encap)
99 features &= skb->dev->hw_enc_features;
100 SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
101
102 ipv6h = ipv6_hdr(skb);
103 __skb_pull(skb, sizeof(*ipv6h));
104 segs = ERR_PTR(-EPROTONOSUPPORT);
105
106 proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
107
108 if (skb->encapsulation &&
109 skb_shinfo(skb)->gso_type & (SKB_GSO_IPXIP4 | SKB_GSO_IPXIP6))
110 udpfrag = proto == IPPROTO_UDP && encap &&
111 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
112 else
113 udpfrag = proto == IPPROTO_UDP && !skb->encapsulation &&
114 (skb_shinfo(skb)->gso_type & SKB_GSO_UDP);
115
116 ops = rcu_dereference(inet6_offloads[proto]);
117 if (likely(ops && ops->callbacks.gso_segment)) {
118 skb_reset_transport_header(skb);
119 segs = ops->callbacks.gso_segment(skb, features);
120 if (!segs)
121 skb->network_header = skb_mac_header(skb) + nhoff - skb->head;
122 }
123
124 if (IS_ERR_OR_NULL(segs))
125 goto out;
126
127 gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL);
128
129 for (skb = segs; skb; skb = skb->next) {
130 ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
131 if (gso_partial && skb_is_gso(skb))
132 payload_len = skb_shinfo(skb)->gso_size +
133 SKB_GSO_CB(skb)->data_offset +
134 skb->head - (unsigned char *)(ipv6h + 1);
135 else
136 payload_len = skb->len - nhoff - sizeof(*ipv6h);
137 ipv6h->payload_len = htons(payload_len);
138 skb->network_header = (u8 *)ipv6h - skb->head;
139 skb_reset_mac_len(skb);
140
141 if (udpfrag) {
142 int err = ip6_find_1stfragopt(skb, &prevhdr);
143 if (err < 0) {
144 kfree_skb_list(segs);
145 return ERR_PTR(err);
146 }
147 fptr = (struct frag_hdr *)((u8 *)ipv6h + err);
148 fptr->frag_off = htons(offset);
149 if (skb->next)
150 fptr->frag_off |= htons(IP6_MF);
151 offset += (ntohs(ipv6h->payload_len) -
152 sizeof(struct frag_hdr));
153 }
154 if (encap)
155 skb_reset_inner_headers(skb);
156 }
157
158out:
159 return segs;
160}
161
162/* Return the total length of all the extension hdrs, following the same
163 * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
164 */
165static int ipv6_exthdrs_len(struct ipv6hdr *iph,
166 const struct net_offload **opps)
167{
168 struct ipv6_opt_hdr *opth = (void *)iph;
169 int len = 0, proto, optlen = sizeof(*iph);
170
171 proto = iph->nexthdr;
172 for (;;) {
173 if (proto != NEXTHDR_HOP) {
174 *opps = rcu_dereference(inet6_offloads[proto]);
175 if (unlikely(!(*opps)))
176 break;
177 if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
178 break;
179 }
180 opth = (void *)opth + optlen;
181 optlen = ipv6_optlen(opth);
182 len += optlen;
183 proto = opth->nexthdr;
184 }
185 return len;
186}
187
188INDIRECT_CALLABLE_SCOPE struct sk_buff *ipv6_gro_receive(struct list_head *head,
189 struct sk_buff *skb)
190{
191 const struct net_offload *ops;
192 struct sk_buff *pp = NULL;
193 struct sk_buff *p;
194 struct ipv6hdr *iph;
195 unsigned int nlen;
196 unsigned int hlen;
197 unsigned int off;
198 u16 flush = 1;
199 int proto;
200
201 off = skb_gro_offset(skb);
202 hlen = off + sizeof(*iph);
203 iph = skb_gro_header(skb, hlen, off);
204 if (unlikely(!iph))
205 goto out;
206
207 skb_set_network_header(skb, off);
208 skb_gro_pull(skb, sizeof(*iph));
209 skb_set_transport_header(skb, skb_gro_offset(skb));
210
211 flush += ntohs(iph->payload_len) != skb_gro_len(skb);
212
213 proto = iph->nexthdr;
214 ops = rcu_dereference(inet6_offloads[proto]);
215 if (!ops || !ops->callbacks.gro_receive) {
216 pskb_pull(skb, skb_gro_offset(skb));
217 skb_gro_frag0_invalidate(skb);
218 proto = ipv6_gso_pull_exthdrs(skb, proto);
219 skb_gro_pull(skb, -skb_transport_offset(skb));
220 skb_reset_transport_header(skb);
221 __skb_push(skb, skb_gro_offset(skb));
222
223 ops = rcu_dereference(inet6_offloads[proto]);
224 if (!ops || !ops->callbacks.gro_receive)
225 goto out;
226
227 iph = ipv6_hdr(skb);
228 }
229
230 NAPI_GRO_CB(skb)->proto = proto;
231
232 flush--;
233 nlen = skb_network_header_len(skb);
234
235 list_for_each_entry(p, head, list) {
236 const struct ipv6hdr *iph2;
237 __be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
238
239 if (!NAPI_GRO_CB(p)->same_flow)
240 continue;
241
242 iph2 = (struct ipv6hdr *)(p->data + off);
243 first_word = *(__be32 *)iph ^ *(__be32 *)iph2;
244
245 /* All fields must match except length and Traffic Class.
246 * XXX skbs on the gro_list have all been parsed and pulled
247 * already so we don't need to compare nlen
248 * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
249 * memcmp() alone below is sufficient, right?
250 */
251 if ((first_word & htonl(0xF00FFFFF)) ||
252 !ipv6_addr_equal(&iph->saddr, &iph2->saddr) ||
253 !ipv6_addr_equal(&iph->daddr, &iph2->daddr) ||
254 iph->nexthdr != iph2->nexthdr) {
255not_same_flow:
256 NAPI_GRO_CB(p)->same_flow = 0;
257 continue;
258 }
259 if (unlikely(nlen > sizeof(struct ipv6hdr))) {
260 if (memcmp(iph + 1, iph2 + 1,
261 nlen - sizeof(struct ipv6hdr)))
262 goto not_same_flow;
263 }
264 /* flush if Traffic Class fields are different */
265 NAPI_GRO_CB(p)->flush |= !!((first_word & htonl(0x0FF00000)) |
266 (__force __be32)(iph->hop_limit ^ iph2->hop_limit));
267 NAPI_GRO_CB(p)->flush |= flush;
268
269 /* If the previous IP ID value was based on an atomic
270 * datagram we can overwrite the value and ignore it.
271 */
272 if (NAPI_GRO_CB(skb)->is_atomic)
273 NAPI_GRO_CB(p)->flush_id = 0;
274 }
275
276 NAPI_GRO_CB(skb)->is_atomic = true;
277 NAPI_GRO_CB(skb)->flush |= flush;
278
279 skb_gro_postpull_rcsum(skb, iph, nlen);
280
281 pp = indirect_call_gro_receive_l4(tcp6_gro_receive, udp6_gro_receive,
282 ops->callbacks.gro_receive, head, skb);
283
284out:
285 skb_gro_flush_final(skb, pp, flush);
286
287 return pp;
288}
289
290static struct sk_buff *sit_ip6ip6_gro_receive(struct list_head *head,
291 struct sk_buff *skb)
292{
293 /* Common GRO receive for SIT and IP6IP6 */
294
295 if (NAPI_GRO_CB(skb)->encap_mark) {
296 NAPI_GRO_CB(skb)->flush = 1;
297 return NULL;
298 }
299
300 NAPI_GRO_CB(skb)->encap_mark = 1;
301
302 return ipv6_gro_receive(head, skb);
303}
304
305static struct sk_buff *ip4ip6_gro_receive(struct list_head *head,
306 struct sk_buff *skb)
307{
308 /* Common GRO receive for SIT and IP6IP6 */
309
310 if (NAPI_GRO_CB(skb)->encap_mark) {
311 NAPI_GRO_CB(skb)->flush = 1;
312 return NULL;
313 }
314
315 NAPI_GRO_CB(skb)->encap_mark = 1;
316
317 return inet_gro_receive(head, skb);
318}
319
320INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
321{
322 const struct net_offload *ops;
323 struct ipv6hdr *iph;
324 int err = -ENOSYS;
325 u32 payload_len;
326
327 if (skb->encapsulation) {
328 skb_set_inner_protocol(skb, cpu_to_be16(ETH_P_IPV6));
329 skb_set_inner_network_header(skb, nhoff);
330 }
331
332 payload_len = skb->len - nhoff - sizeof(*iph);
333 if (unlikely(payload_len > IPV6_MAXPLEN)) {
334 struct hop_jumbo_hdr *hop_jumbo;
335 int hoplen = sizeof(*hop_jumbo);
336
337 /* Move network header left */
338 memmove(skb_mac_header(skb) - hoplen, skb_mac_header(skb),
339 skb->transport_header - skb->mac_header);
340 skb->data -= hoplen;
341 skb->len += hoplen;
342 skb->mac_header -= hoplen;
343 skb->network_header -= hoplen;
344 iph = (struct ipv6hdr *)(skb->data + nhoff);
345 hop_jumbo = (struct hop_jumbo_hdr *)(iph + 1);
346
347 /* Build hop-by-hop options */
348 hop_jumbo->nexthdr = iph->nexthdr;
349 hop_jumbo->hdrlen = 0;
350 hop_jumbo->tlv_type = IPV6_TLV_JUMBO;
351 hop_jumbo->tlv_len = 4;
352 hop_jumbo->jumbo_payload_len = htonl(payload_len + hoplen);
353
354 iph->nexthdr = NEXTHDR_HOP;
355 iph->payload_len = 0;
356 } else {
357 iph = (struct ipv6hdr *)(skb->data + nhoff);
358 iph->payload_len = htons(payload_len);
359 }
360
361 nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
362 if (WARN_ON(!ops || !ops->callbacks.gro_complete))
363 goto out;
364
365 err = INDIRECT_CALL_L4(ops->callbacks.gro_complete, tcp6_gro_complete,
366 udp6_gro_complete, skb, nhoff);
367
368out:
369 return err;
370}
371
372static int sit_gro_complete(struct sk_buff *skb, int nhoff)
373{
374 skb->encapsulation = 1;
375 skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
376 return ipv6_gro_complete(skb, nhoff);
377}
378
379static int ip6ip6_gro_complete(struct sk_buff *skb, int nhoff)
380{
381 skb->encapsulation = 1;
382 skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;
383 return ipv6_gro_complete(skb, nhoff);
384}
385
386static int ip4ip6_gro_complete(struct sk_buff *skb, int nhoff)
387{
388 skb->encapsulation = 1;
389 skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;
390 return inet_gro_complete(skb, nhoff);
391}
392
393static struct packet_offload ipv6_packet_offload __read_mostly = {
394 .type = cpu_to_be16(ETH_P_IPV6),
395 .callbacks = {
396 .gso_segment = ipv6_gso_segment,
397 .gro_receive = ipv6_gro_receive,
398 .gro_complete = ipv6_gro_complete,
399 },
400};
401
402static struct sk_buff *sit_gso_segment(struct sk_buff *skb,
403 netdev_features_t features)
404{
405 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP4))
406 return ERR_PTR(-EINVAL);
407
408 return ipv6_gso_segment(skb, features);
409}
410
411static struct sk_buff *ip4ip6_gso_segment(struct sk_buff *skb,
412 netdev_features_t features)
413{
414 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP6))
415 return ERR_PTR(-EINVAL);
416
417 return inet_gso_segment(skb, features);
418}
419
420static struct sk_buff *ip6ip6_gso_segment(struct sk_buff *skb,
421 netdev_features_t features)
422{
423 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_IPXIP6))
424 return ERR_PTR(-EINVAL);
425
426 return ipv6_gso_segment(skb, features);
427}
428
429static const struct net_offload sit_offload = {
430 .callbacks = {
431 .gso_segment = sit_gso_segment,
432 .gro_receive = sit_ip6ip6_gro_receive,
433 .gro_complete = sit_gro_complete,
434 },
435};
436
437static const struct net_offload ip4ip6_offload = {
438 .callbacks = {
439 .gso_segment = ip4ip6_gso_segment,
440 .gro_receive = ip4ip6_gro_receive,
441 .gro_complete = ip4ip6_gro_complete,
442 },
443};
444
445static const struct net_offload ip6ip6_offload = {
446 .callbacks = {
447 .gso_segment = ip6ip6_gso_segment,
448 .gro_receive = sit_ip6ip6_gro_receive,
449 .gro_complete = ip6ip6_gro_complete,
450 },
451};
452static int __init ipv6_offload_init(void)
453{
454
455 if (tcpv6_offload_init() < 0)
456 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
457 if (ipv6_exthdrs_offload_init() < 0)
458 pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);
459
460 dev_add_offload(&ipv6_packet_offload);
461
462 inet_add_offload(&sit_offload, IPPROTO_IPV6);
463 inet6_add_offload(&ip6ip6_offload, IPPROTO_IPV6);
464 inet6_add_offload(&ip4ip6_offload, IPPROTO_IPIP);
465
466 return 0;
467}
468
469fs_initcall(ipv6_offload_init);