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1/*
2 * IPV4 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/udp.h>
30
31static struct sk_buff **esp4_gro_receive(struct sk_buff **head,
32 struct sk_buff *skb)
33{
34 int offset = skb_gro_offset(skb);
35 struct xfrm_offload *xo;
36 struct xfrm_state *x;
37 __be32 seq;
38 __be32 spi;
39 int err;
40
41 if (!pskb_pull(skb, offset))
42 return NULL;
43
44 if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0)
45 goto out;
46
47 xo = xfrm_offload(skb);
48 if (!xo || !(xo->flags & CRYPTO_DONE)) {
49 err = secpath_set(skb);
50 if (err)
51 goto out;
52
53 if (skb->sp->len == XFRM_MAX_DEPTH)
54 goto out;
55
56 x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
57 (xfrm_address_t *)&ip_hdr(skb)->daddr,
58 spi, IPPROTO_ESP, AF_INET);
59 if (!x)
60 goto out;
61
62 skb->sp->xvec[skb->sp->len++] = x;
63 skb->sp->olen++;
64
65 xo = xfrm_offload(skb);
66 if (!xo) {
67 xfrm_state_put(x);
68 goto out;
69 }
70 }
71
72 xo->flags |= XFRM_GRO;
73
74 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;
75 XFRM_SPI_SKB_CB(skb)->family = AF_INET;
76 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
77 XFRM_SPI_SKB_CB(skb)->seq = seq;
78
79 /* We don't need to handle errors from xfrm_input, it does all
80 * the error handling and frees the resources on error. */
81 xfrm_input(skb, IPPROTO_ESP, spi, -2);
82
83 return ERR_PTR(-EINPROGRESS);
84out:
85 skb_push(skb, offset);
86 NAPI_GRO_CB(skb)->same_flow = 0;
87 NAPI_GRO_CB(skb)->flush = 1;
88
89 return NULL;
90}
91
92static void esp4_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
93{
94 struct ip_esp_hdr *esph;
95 struct iphdr *iph = ip_hdr(skb);
96 struct xfrm_offload *xo = xfrm_offload(skb);
97 int proto = iph->protocol;
98
99 skb_push(skb, -skb_network_offset(skb));
100 esph = ip_esp_hdr(skb);
101 *skb_mac_header(skb) = IPPROTO_ESP;
102
103 esph->spi = x->id.spi;
104 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
105
106 xo->proto = proto;
107}
108
109static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
110 netdev_features_t features)
111{
112 struct xfrm_state *x;
113 struct ip_esp_hdr *esph;
114 struct crypto_aead *aead;
115 netdev_features_t esp_features = features;
116 struct xfrm_offload *xo = xfrm_offload(skb);
117
118 if (!xo)
119 return ERR_PTR(-EINVAL);
120
121 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
122 return ERR_PTR(-EINVAL);
123
124 x = skb->sp->xvec[skb->sp->len - 1];
125 aead = x->data;
126 esph = ip_esp_hdr(skb);
127
128 if (esph->spi != x->id.spi)
129 return ERR_PTR(-EINVAL);
130
131 if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
132 return ERR_PTR(-EINVAL);
133
134 __skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
135
136 skb->encap_hdr_csum = 1;
137
138 if (!(features & NETIF_F_HW_ESP) || !x->xso.offload_handle ||
139 (x->xso.dev != skb->dev))
140 esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
141 else if (!(features & NETIF_F_HW_ESP_TX_CSUM))
142 esp_features = features & ~NETIF_F_CSUM_MASK;
143
144 xo->flags |= XFRM_GSO_SEGMENT;
145
146 return x->outer_mode->gso_segment(x, skb, esp_features);
147}
148
149static int esp_input_tail(struct xfrm_state *x, struct sk_buff *skb)
150{
151 struct crypto_aead *aead = x->data;
152 struct xfrm_offload *xo = xfrm_offload(skb);
153
154 if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
155 return -EINVAL;
156
157 if (!(xo->flags & CRYPTO_DONE))
158 skb->ip_summed = CHECKSUM_NONE;
159
160 return esp_input_done2(skb, 0);
161}
162
163static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features)
164{
165 int err;
166 int alen;
167 int blksize;
168 struct xfrm_offload *xo;
169 struct ip_esp_hdr *esph;
170 struct crypto_aead *aead;
171 struct esp_info esp;
172 bool hw_offload = true;
173 __u32 seq;
174
175 esp.inplace = true;
176
177 xo = xfrm_offload(skb);
178
179 if (!xo)
180 return -EINVAL;
181
182 if (!(features & NETIF_F_HW_ESP) || !x->xso.offload_handle ||
183 (x->xso.dev != skb->dev)) {
184 xo->flags |= CRYPTO_FALLBACK;
185 hw_offload = false;
186 }
187
188 esp.proto = xo->proto;
189
190 /* skb is pure payload to encrypt */
191
192 aead = x->data;
193 alen = crypto_aead_authsize(aead);
194
195 esp.tfclen = 0;
196 /* XXX: Add support for tfc padding here. */
197
198 blksize = ALIGN(crypto_aead_blocksize(aead), 4);
199 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
200 esp.plen = esp.clen - skb->len - esp.tfclen;
201 esp.tailen = esp.tfclen + esp.plen + alen;
202
203 esp.esph = ip_esp_hdr(skb);
204
205
206 if (!hw_offload || (hw_offload && !skb_is_gso(skb))) {
207 esp.nfrags = esp_output_head(x, skb, &esp);
208 if (esp.nfrags < 0)
209 return esp.nfrags;
210 }
211
212 seq = xo->seq.low;
213
214 esph = esp.esph;
215 esph->spi = x->id.spi;
216
217 skb_push(skb, -skb_network_offset(skb));
218
219 if (xo->flags & XFRM_GSO_SEGMENT) {
220 esph->seq_no = htonl(seq);
221
222 if (!skb_is_gso(skb))
223 xo->seq.low++;
224 else
225 xo->seq.low += skb_shinfo(skb)->gso_segs;
226 }
227
228 esp.seqno = cpu_to_be64(seq + ((u64)xo->seq.hi << 32));
229
230 ip_hdr(skb)->tot_len = htons(skb->len);
231 ip_send_check(ip_hdr(skb));
232
233 if (hw_offload)
234 return 0;
235
236 err = esp_output_tail(x, skb, &esp);
237 if (err)
238 return err;
239
240 secpath_reset(skb);
241
242 return 0;
243}
244
245static const struct net_offload esp4_offload = {
246 .callbacks = {
247 .gro_receive = esp4_gro_receive,
248 .gso_segment = esp4_gso_segment,
249 },
250};
251
252static const struct xfrm_type_offload esp_type_offload = {
253 .description = "ESP4 OFFLOAD",
254 .owner = THIS_MODULE,
255 .proto = IPPROTO_ESP,
256 .input_tail = esp_input_tail,
257 .xmit = esp_xmit,
258 .encap = esp4_gso_encap,
259};
260
261static int __init esp4_offload_init(void)
262{
263 if (xfrm_register_type_offload(&esp_type_offload, AF_INET) < 0) {
264 pr_info("%s: can't add xfrm type offload\n", __func__);
265 return -EAGAIN;
266 }
267
268 return inet_add_offload(&esp4_offload, IPPROTO_ESP);
269}
270
271static void __exit esp4_offload_exit(void)
272{
273 if (xfrm_unregister_type_offload(&esp_type_offload, AF_INET) < 0)
274 pr_info("%s: can't remove xfrm type offload\n", __func__);
275
276 inet_del_offload(&esp4_offload, IPPROTO_ESP);
277}
278
279module_init(esp4_offload_init);
280module_exit(esp4_offload_exit);
281MODULE_LICENSE("GPL");
282MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
283MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET, XFRM_PROTO_ESP);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * IPV4 GSO/GRO offload support
4 * Linux INET implementation
5 *
6 * Copyright (C) 2016 secunet Security Networks AG
7 * Author: Steffen Klassert <steffen.klassert@secunet.com>
8 *
9 * ESP GRO support
10 */
11
12#include <linux/skbuff.h>
13#include <linux/init.h>
14#include <net/protocol.h>
15#include <crypto/aead.h>
16#include <crypto/authenc.h>
17#include <linux/err.h>
18#include <linux/module.h>
19#include <net/ip.h>
20#include <net/xfrm.h>
21#include <net/esp.h>
22#include <linux/scatterlist.h>
23#include <linux/kernel.h>
24#include <linux/slab.h>
25#include <linux/spinlock.h>
26#include <net/udp.h>
27
28static struct sk_buff *esp4_gro_receive(struct list_head *head,
29 struct sk_buff *skb)
30{
31 int offset = skb_gro_offset(skb);
32 struct xfrm_offload *xo;
33 struct xfrm_state *x;
34 __be32 seq;
35 __be32 spi;
36
37 if (!pskb_pull(skb, offset))
38 return NULL;
39
40 if (xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq) != 0)
41 goto out;
42
43 xo = xfrm_offload(skb);
44 if (!xo || !(xo->flags & CRYPTO_DONE)) {
45 struct sec_path *sp = secpath_set(skb);
46
47 if (!sp)
48 goto out;
49
50 if (sp->len == XFRM_MAX_DEPTH)
51 goto out_reset;
52
53 x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
54 (xfrm_address_t *)&ip_hdr(skb)->daddr,
55 spi, IPPROTO_ESP, AF_INET);
56 if (!x)
57 goto out_reset;
58
59 skb->mark = xfrm_smark_get(skb->mark, x);
60
61 sp->xvec[sp->len++] = x;
62 sp->olen++;
63
64 xo = xfrm_offload(skb);
65 if (!xo)
66 goto out_reset;
67 }
68
69 xo->flags |= XFRM_GRO;
70
71 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;
72 XFRM_SPI_SKB_CB(skb)->family = AF_INET;
73 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
74 XFRM_SPI_SKB_CB(skb)->seq = seq;
75
76 /* We don't need to handle errors from xfrm_input, it does all
77 * the error handling and frees the resources on error. */
78 xfrm_input(skb, IPPROTO_ESP, spi, -2);
79
80 return ERR_PTR(-EINPROGRESS);
81out_reset:
82 secpath_reset(skb);
83out:
84 skb_push(skb, offset);
85 NAPI_GRO_CB(skb)->same_flow = 0;
86 NAPI_GRO_CB(skb)->flush = 1;
87
88 return NULL;
89}
90
91static void esp4_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
92{
93 struct ip_esp_hdr *esph;
94 struct iphdr *iph = ip_hdr(skb);
95 struct xfrm_offload *xo = xfrm_offload(skb);
96 int proto = iph->protocol;
97
98 skb_push(skb, -skb_network_offset(skb));
99 esph = ip_esp_hdr(skb);
100 *skb_mac_header(skb) = IPPROTO_ESP;
101
102 esph->spi = x->id.spi;
103 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
104
105 xo->proto = proto;
106}
107
108static struct sk_buff *xfrm4_tunnel_gso_segment(struct xfrm_state *x,
109 struct sk_buff *skb,
110 netdev_features_t features)
111{
112 __skb_push(skb, skb->mac_len);
113 return skb_mac_gso_segment(skb, features);
114}
115
116static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x,
117 struct sk_buff *skb,
118 netdev_features_t features)
119{
120 const struct net_offload *ops;
121 struct sk_buff *segs = ERR_PTR(-EINVAL);
122 struct xfrm_offload *xo = xfrm_offload(skb);
123
124 skb->transport_header += x->props.header_len;
125 ops = rcu_dereference(inet_offloads[xo->proto]);
126 if (likely(ops && ops->callbacks.gso_segment))
127 segs = ops->callbacks.gso_segment(skb, features);
128
129 return segs;
130}
131
132static struct sk_buff *xfrm4_beet_gso_segment(struct xfrm_state *x,
133 struct sk_buff *skb,
134 netdev_features_t features)
135{
136 struct xfrm_offload *xo = xfrm_offload(skb);
137 struct sk_buff *segs = ERR_PTR(-EINVAL);
138 const struct net_offload *ops;
139 u8 proto = xo->proto;
140
141 skb->transport_header += x->props.header_len;
142
143 if (x->sel.family != AF_INET6) {
144 if (proto == IPPROTO_BEETPH) {
145 struct ip_beet_phdr *ph =
146 (struct ip_beet_phdr *)skb->data;
147
148 skb->transport_header += ph->hdrlen * 8;
149 proto = ph->nexthdr;
150 } else {
151 skb->transport_header -= IPV4_BEET_PHMAXLEN;
152 }
153 } else {
154 __be16 frag;
155
156 skb->transport_header +=
157 ipv6_skip_exthdr(skb, 0, &proto, &frag);
158 if (proto == IPPROTO_TCP)
159 skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4;
160 }
161
162 __skb_pull(skb, skb_transport_offset(skb));
163 ops = rcu_dereference(inet_offloads[proto]);
164 if (likely(ops && ops->callbacks.gso_segment))
165 segs = ops->callbacks.gso_segment(skb, features);
166
167 return segs;
168}
169
170static struct sk_buff *xfrm4_outer_mode_gso_segment(struct xfrm_state *x,
171 struct sk_buff *skb,
172 netdev_features_t features)
173{
174 switch (x->outer_mode.encap) {
175 case XFRM_MODE_TUNNEL:
176 return xfrm4_tunnel_gso_segment(x, skb, features);
177 case XFRM_MODE_TRANSPORT:
178 return xfrm4_transport_gso_segment(x, skb, features);
179 case XFRM_MODE_BEET:
180 return xfrm4_beet_gso_segment(x, skb, features);
181 }
182
183 return ERR_PTR(-EOPNOTSUPP);
184}
185
186static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
187 netdev_features_t features)
188{
189 struct xfrm_state *x;
190 struct ip_esp_hdr *esph;
191 struct crypto_aead *aead;
192 netdev_features_t esp_features = features;
193 struct xfrm_offload *xo = xfrm_offload(skb);
194 struct sec_path *sp;
195
196 if (!xo)
197 return ERR_PTR(-EINVAL);
198
199 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
200 return ERR_PTR(-EINVAL);
201
202 sp = skb_sec_path(skb);
203 x = sp->xvec[sp->len - 1];
204 aead = x->data;
205 esph = ip_esp_hdr(skb);
206
207 if (esph->spi != x->id.spi)
208 return ERR_PTR(-EINVAL);
209
210 if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
211 return ERR_PTR(-EINVAL);
212
213 __skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
214
215 skb->encap_hdr_csum = 1;
216
217 if ((!(skb->dev->gso_partial_features & NETIF_F_HW_ESP) &&
218 !(features & NETIF_F_HW_ESP)) || x->xso.dev != skb->dev)
219 esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK |
220 NETIF_F_SCTP_CRC);
221 else if (!(features & NETIF_F_HW_ESP_TX_CSUM) &&
222 !(skb->dev->gso_partial_features & NETIF_F_HW_ESP_TX_CSUM))
223 esp_features = features & ~(NETIF_F_CSUM_MASK |
224 NETIF_F_SCTP_CRC);
225
226 xo->flags |= XFRM_GSO_SEGMENT;
227
228 return xfrm4_outer_mode_gso_segment(x, skb, esp_features);
229}
230
231static int esp_input_tail(struct xfrm_state *x, struct sk_buff *skb)
232{
233 struct crypto_aead *aead = x->data;
234 struct xfrm_offload *xo = xfrm_offload(skb);
235
236 if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
237 return -EINVAL;
238
239 if (!(xo->flags & CRYPTO_DONE))
240 skb->ip_summed = CHECKSUM_NONE;
241
242 return esp_input_done2(skb, 0);
243}
244
245static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features)
246{
247 int err;
248 int alen;
249 int blksize;
250 struct xfrm_offload *xo;
251 struct ip_esp_hdr *esph;
252 struct crypto_aead *aead;
253 struct esp_info esp;
254 bool hw_offload = true;
255 __u32 seq;
256
257 esp.inplace = true;
258
259 xo = xfrm_offload(skb);
260
261 if (!xo)
262 return -EINVAL;
263
264 if ((!(features & NETIF_F_HW_ESP) &&
265 !(skb->dev->gso_partial_features & NETIF_F_HW_ESP)) ||
266 x->xso.dev != skb->dev) {
267 xo->flags |= CRYPTO_FALLBACK;
268 hw_offload = false;
269 }
270
271 esp.proto = xo->proto;
272
273 /* skb is pure payload to encrypt */
274
275 aead = x->data;
276 alen = crypto_aead_authsize(aead);
277
278 esp.tfclen = 0;
279 /* XXX: Add support for tfc padding here. */
280
281 blksize = ALIGN(crypto_aead_blocksize(aead), 4);
282 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
283 esp.plen = esp.clen - skb->len - esp.tfclen;
284 esp.tailen = esp.tfclen + esp.plen + alen;
285
286 esp.esph = ip_esp_hdr(skb);
287
288
289 if (!hw_offload || !skb_is_gso(skb)) {
290 esp.nfrags = esp_output_head(x, skb, &esp);
291 if (esp.nfrags < 0)
292 return esp.nfrags;
293 }
294
295 seq = xo->seq.low;
296
297 esph = esp.esph;
298 esph->spi = x->id.spi;
299
300 skb_push(skb, -skb_network_offset(skb));
301
302 if (xo->flags & XFRM_GSO_SEGMENT) {
303 esph->seq_no = htonl(seq);
304
305 if (!skb_is_gso(skb))
306 xo->seq.low++;
307 else
308 xo->seq.low += skb_shinfo(skb)->gso_segs;
309 }
310
311 esp.seqno = cpu_to_be64(seq + ((u64)xo->seq.hi << 32));
312
313 ip_hdr(skb)->tot_len = htons(skb->len);
314 ip_send_check(ip_hdr(skb));
315
316 if (hw_offload) {
317 if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
318 return -ENOMEM;
319
320 xo = xfrm_offload(skb);
321 if (!xo)
322 return -EINVAL;
323
324 xo->flags |= XFRM_XMIT;
325 return 0;
326 }
327
328 err = esp_output_tail(x, skb, &esp);
329 if (err)
330 return err;
331
332 secpath_reset(skb);
333
334 return 0;
335}
336
337static const struct net_offload esp4_offload = {
338 .callbacks = {
339 .gro_receive = esp4_gro_receive,
340 .gso_segment = esp4_gso_segment,
341 },
342};
343
344static const struct xfrm_type_offload esp_type_offload = {
345 .owner = THIS_MODULE,
346 .proto = IPPROTO_ESP,
347 .input_tail = esp_input_tail,
348 .xmit = esp_xmit,
349 .encap = esp4_gso_encap,
350};
351
352static int __init esp4_offload_init(void)
353{
354 if (xfrm_register_type_offload(&esp_type_offload, AF_INET) < 0) {
355 pr_info("%s: can't add xfrm type offload\n", __func__);
356 return -EAGAIN;
357 }
358
359 return inet_add_offload(&esp4_offload, IPPROTO_ESP);
360}
361
362static void __exit esp4_offload_exit(void)
363{
364 xfrm_unregister_type_offload(&esp_type_offload, AF_INET);
365 inet_del_offload(&esp4_offload, IPPROTO_ESP);
366}
367
368module_init(esp4_offload_init);
369module_exit(esp4_offload_exit);
370MODULE_LICENSE("GPL");
371MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
372MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET, XFRM_PROTO_ESP);
373MODULE_DESCRIPTION("IPV4 GSO/GRO offload support");