]>
Commit | Line | Data |
---|---|---|
7785bba2 SK |
1 | /* |
2 | * IPV6 GSO/GRO offload support | |
3 | * Linux INET implementation | |
4 | * | |
5 | * Copyright (C) 2016 secunet Security Networks AG | |
6 | * Author: Steffen Klassert <steffen.klassert@secunet.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify it | |
9 | * under the terms and conditions of the GNU General Public License, | |
10 | * version 2, as published by the Free Software Foundation. | |
11 | * | |
12 | * ESP GRO support | |
13 | */ | |
14 | ||
15 | #include <linux/skbuff.h> | |
16 | #include <linux/init.h> | |
17 | #include <net/protocol.h> | |
18 | #include <crypto/aead.h> | |
19 | #include <crypto/authenc.h> | |
20 | #include <linux/err.h> | |
21 | #include <linux/module.h> | |
22 | #include <net/ip.h> | |
23 | #include <net/xfrm.h> | |
24 | #include <net/esp.h> | |
25 | #include <linux/scatterlist.h> | |
26 | #include <linux/kernel.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/spinlock.h> | |
29 | #include <net/ip6_route.h> | |
30 | #include <net/ipv6.h> | |
31 | #include <linux/icmpv6.h> | |
32 | ||
ca3a1b85 YK |
33 | static __u16 esp6_nexthdr_esp_offset(struct ipv6hdr *ipv6_hdr, int nhlen) |
34 | { | |
35 | int off = sizeof(struct ipv6hdr); | |
36 | struct ipv6_opt_hdr *exthdr; | |
37 | ||
38 | if (likely(ipv6_hdr->nexthdr == NEXTHDR_ESP)) | |
39 | return offsetof(struct ipv6hdr, nexthdr); | |
40 | ||
41 | while (off < nhlen) { | |
42 | exthdr = (void *)ipv6_hdr + off; | |
43 | if (exthdr->nexthdr == NEXTHDR_ESP) | |
44 | return off; | |
45 | ||
46 | off += ipv6_optlen(exthdr); | |
47 | } | |
48 | ||
49 | return 0; | |
50 | } | |
51 | ||
7785bba2 SK |
52 | static struct sk_buff **esp6_gro_receive(struct sk_buff **head, |
53 | struct sk_buff *skb) | |
54 | { | |
55 | int offset = skb_gro_offset(skb); | |
56 | struct xfrm_offload *xo; | |
57 | struct xfrm_state *x; | |
58 | __be32 seq; | |
59 | __be32 spi; | |
ca3a1b85 | 60 | int nhoff; |
7785bba2 SK |
61 | int err; |
62 | ||
63 | skb_pull(skb, offset); | |
64 | ||
65 | if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0) | |
66 | goto out; | |
67 | ||
bcd1f8a4 SK |
68 | xo = xfrm_offload(skb); |
69 | if (!xo || !(xo->flags & CRYPTO_DONE)) { | |
70 | err = secpath_set(skb); | |
71 | if (err) | |
72 | goto out; | |
7785bba2 | 73 | |
bcd1f8a4 SK |
74 | if (skb->sp->len == XFRM_MAX_DEPTH) |
75 | goto out; | |
7785bba2 | 76 | |
bcd1f8a4 SK |
77 | x = xfrm_state_lookup(dev_net(skb->dev), skb->mark, |
78 | (xfrm_address_t *)&ipv6_hdr(skb)->daddr, | |
79 | spi, IPPROTO_ESP, AF_INET6); | |
80 | if (!x) | |
81 | goto out; | |
7785bba2 | 82 | |
bcd1f8a4 SK |
83 | skb->sp->xvec[skb->sp->len++] = x; |
84 | skb->sp->olen++; | |
7785bba2 | 85 | |
bcd1f8a4 SK |
86 | xo = xfrm_offload(skb); |
87 | if (!xo) { | |
88 | xfrm_state_put(x); | |
89 | goto out; | |
90 | } | |
7785bba2 | 91 | } |
bcd1f8a4 | 92 | |
7785bba2 SK |
93 | xo->flags |= XFRM_GRO; |
94 | ||
ca3a1b85 YK |
95 | nhoff = esp6_nexthdr_esp_offset(ipv6_hdr(skb), offset); |
96 | if (!nhoff) | |
97 | goto out; | |
98 | ||
99 | IP6CB(skb)->nhoff = nhoff; | |
7785bba2 SK |
100 | XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL; |
101 | XFRM_SPI_SKB_CB(skb)->family = AF_INET6; | |
102 | XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr); | |
103 | XFRM_SPI_SKB_CB(skb)->seq = seq; | |
104 | ||
105 | /* We don't need to handle errors from xfrm_input, it does all | |
106 | * the error handling and frees the resources on error. */ | |
107 | xfrm_input(skb, IPPROTO_ESP, spi, -2); | |
108 | ||
109 | return ERR_PTR(-EINPROGRESS); | |
110 | out: | |
111 | skb_push(skb, offset); | |
112 | NAPI_GRO_CB(skb)->same_flow = 0; | |
113 | NAPI_GRO_CB(skb)->flush = 1; | |
114 | ||
115 | return NULL; | |
116 | } | |
117 | ||
7862b405 SK |
118 | static void esp6_gso_encap(struct xfrm_state *x, struct sk_buff *skb) |
119 | { | |
120 | struct ip_esp_hdr *esph; | |
121 | struct ipv6hdr *iph = ipv6_hdr(skb); | |
122 | struct xfrm_offload *xo = xfrm_offload(skb); | |
123 | int proto = iph->nexthdr; | |
124 | ||
125 | skb_push(skb, -skb_network_offset(skb)); | |
126 | esph = ip_esp_hdr(skb); | |
127 | *skb_mac_header(skb) = IPPROTO_ESP; | |
128 | ||
129 | esph->spi = x->id.spi; | |
130 | esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); | |
131 | ||
132 | xo->proto = proto; | |
133 | } | |
134 | ||
135 | static struct sk_buff *esp6_gso_segment(struct sk_buff *skb, | |
136 | netdev_features_t features) | |
137 | { | |
138 | __u32 seq; | |
139 | int err = 0; | |
140 | struct sk_buff *skb2; | |
141 | struct xfrm_state *x; | |
142 | struct ip_esp_hdr *esph; | |
143 | struct crypto_aead *aead; | |
144 | struct sk_buff *segs = ERR_PTR(-EINVAL); | |
145 | netdev_features_t esp_features = features; | |
146 | struct xfrm_offload *xo = xfrm_offload(skb); | |
147 | ||
ffa6f571 | 148 | if (!xo) |
7862b405 SK |
149 | goto out; |
150 | ||
151 | seq = xo->seq.low; | |
152 | ||
153 | x = skb->sp->xvec[skb->sp->len - 1]; | |
154 | aead = x->data; | |
155 | esph = ip_esp_hdr(skb); | |
156 | ||
157 | if (esph->spi != x->id.spi) | |
158 | goto out; | |
159 | ||
160 | if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) | |
161 | goto out; | |
162 | ||
163 | __skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)); | |
164 | ||
165 | skb->encap_hdr_csum = 1; | |
166 | ||
167 | if (!(features & NETIF_F_HW_ESP)) | |
168 | esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK); | |
169 | ||
170 | segs = x->outer_mode->gso_segment(x, skb, esp_features); | |
171 | if (IS_ERR_OR_NULL(segs)) | |
172 | goto out; | |
173 | ||
174 | __skb_pull(skb, skb->data - skb_mac_header(skb)); | |
175 | ||
176 | skb2 = segs; | |
177 | do { | |
178 | struct sk_buff *nskb = skb2->next; | |
179 | ||
180 | xo = xfrm_offload(skb2); | |
181 | xo->flags |= XFRM_GSO_SEGMENT; | |
182 | xo->seq.low = seq; | |
183 | xo->seq.hi = xfrm_replay_seqhi(x, seq); | |
184 | ||
185 | if(!(features & NETIF_F_HW_ESP)) | |
186 | xo->flags |= CRYPTO_FALLBACK; | |
187 | ||
188 | x->outer_mode->xmit(x, skb2); | |
189 | ||
190 | err = x->type_offload->xmit(x, skb2, esp_features); | |
191 | if (err) { | |
192 | kfree_skb_list(segs); | |
193 | return ERR_PTR(err); | |
194 | } | |
195 | ||
196 | if (!skb_is_gso(skb2)) | |
197 | seq++; | |
198 | else | |
199 | seq += skb_shinfo(skb2)->gso_segs; | |
200 | ||
201 | skb_push(skb2, skb2->mac_len); | |
202 | skb2 = nskb; | |
203 | } while (skb2); | |
204 | ||
205 | out: | |
206 | return segs; | |
207 | } | |
208 | ||
383d0350 SK |
209 | static int esp6_input_tail(struct xfrm_state *x, struct sk_buff *skb) |
210 | { | |
211 | struct crypto_aead *aead = x->data; | |
e51a6472 | 212 | struct xfrm_offload *xo = xfrm_offload(skb); |
383d0350 SK |
213 | |
214 | if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead))) | |
215 | return -EINVAL; | |
216 | ||
e51a6472 IT |
217 | if (!(xo->flags & CRYPTO_DONE)) |
218 | skb->ip_summed = CHECKSUM_NONE; | |
383d0350 SK |
219 | |
220 | return esp6_input_done2(skb, 0); | |
221 | } | |
222 | ||
223 | static int esp6_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) | |
224 | { | |
225 | int err; | |
226 | int alen; | |
227 | int blksize; | |
228 | struct xfrm_offload *xo; | |
229 | struct ip_esp_hdr *esph; | |
230 | struct crypto_aead *aead; | |
231 | struct esp_info esp; | |
232 | bool hw_offload = true; | |
233 | ||
234 | esp.inplace = true; | |
235 | ||
236 | xo = xfrm_offload(skb); | |
237 | ||
238 | if (!xo) | |
239 | return -EINVAL; | |
240 | ||
8f92e03e IT |
241 | if (!(features & NETIF_F_HW_ESP) || !x->xso.offload_handle || |
242 | (x->xso.dev != skb->dev)) { | |
383d0350 | 243 | xo->flags |= CRYPTO_FALLBACK; |
8f92e03e | 244 | hw_offload = false; |
383d0350 SK |
245 | } |
246 | ||
247 | esp.proto = xo->proto; | |
248 | ||
249 | /* skb is pure payload to encrypt */ | |
250 | ||
251 | aead = x->data; | |
252 | alen = crypto_aead_authsize(aead); | |
253 | ||
254 | esp.tfclen = 0; | |
255 | /* XXX: Add support for tfc padding here. */ | |
256 | ||
257 | blksize = ALIGN(crypto_aead_blocksize(aead), 4); | |
258 | esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); | |
259 | esp.plen = esp.clen - skb->len - esp.tfclen; | |
260 | esp.tailen = esp.tfclen + esp.plen + alen; | |
261 | ||
262 | if (!hw_offload || (hw_offload && !skb_is_gso(skb))) { | |
263 | esp.nfrags = esp6_output_head(x, skb, &esp); | |
264 | if (esp.nfrags < 0) | |
265 | return esp.nfrags; | |
266 | } | |
267 | ||
268 | esph = ip_esp_hdr(skb); | |
269 | esph->spi = x->id.spi; | |
270 | ||
271 | skb_push(skb, -skb_network_offset(skb)); | |
272 | ||
273 | if (xo->flags & XFRM_GSO_SEGMENT) { | |
274 | esph->seq_no = htonl(xo->seq.low); | |
275 | } else { | |
276 | int len; | |
277 | ||
278 | len = skb->len - sizeof(struct ipv6hdr); | |
279 | if (len > IPV6_MAXPLEN) | |
280 | len = 0; | |
281 | ||
282 | ipv6_hdr(skb)->payload_len = htons(len); | |
283 | } | |
284 | ||
8f92e03e | 285 | if (hw_offload) |
383d0350 SK |
286 | return 0; |
287 | ||
288 | esp.seqno = cpu_to_be64(xo->seq.low + ((u64)xo->seq.hi << 32)); | |
289 | ||
290 | err = esp6_output_tail(x, skb, &esp); | |
4ff0308f | 291 | if (err) |
383d0350 SK |
292 | return err; |
293 | ||
294 | secpath_reset(skb); | |
295 | ||
296 | return 0; | |
297 | } | |
298 | ||
7785bba2 SK |
299 | static const struct net_offload esp6_offload = { |
300 | .callbacks = { | |
301 | .gro_receive = esp6_gro_receive, | |
7862b405 | 302 | .gso_segment = esp6_gso_segment, |
7785bba2 SK |
303 | }, |
304 | }; | |
305 | ||
383d0350 SK |
306 | static const struct xfrm_type_offload esp6_type_offload = { |
307 | .description = "ESP6 OFFLOAD", | |
308 | .owner = THIS_MODULE, | |
309 | .proto = IPPROTO_ESP, | |
310 | .input_tail = esp6_input_tail, | |
311 | .xmit = esp6_xmit, | |
7862b405 | 312 | .encap = esp6_gso_encap, |
383d0350 SK |
313 | }; |
314 | ||
7785bba2 SK |
315 | static int __init esp6_offload_init(void) |
316 | { | |
383d0350 SK |
317 | if (xfrm_register_type_offload(&esp6_type_offload, AF_INET6) < 0) { |
318 | pr_info("%s: can't add xfrm type offload\n", __func__); | |
319 | return -EAGAIN; | |
320 | } | |
321 | ||
7785bba2 SK |
322 | return inet6_add_offload(&esp6_offload, IPPROTO_ESP); |
323 | } | |
324 | ||
325 | static void __exit esp6_offload_exit(void) | |
326 | { | |
383d0350 SK |
327 | if (xfrm_unregister_type_offload(&esp6_type_offload, AF_INET6) < 0) |
328 | pr_info("%s: can't remove xfrm type offload\n", __func__); | |
329 | ||
7785bba2 SK |
330 | inet6_del_offload(&esp6_offload, IPPROTO_ESP); |
331 | } | |
332 | ||
333 | module_init(esp6_offload_init); | |
334 | module_exit(esp6_offload_exit); | |
335 | MODULE_LICENSE("GPL"); | |
336 | MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>"); | |
ffdb5211 | 337 | MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET6, XFRM_PROTO_ESP); |