1 // SPDX-License-Identifier: GPL-2.0-only
3 * IPV4 GSO/GRO offload support
4 * Linux INET implementation
6 * Copyright (C) 2016 secunet Security Networks AG
7 * Author: Steffen Klassert <steffen.klassert@secunet.com>
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>
22 #include <linux/scatterlist.h>
23 #include <linux/kernel.h>
24 #include <linux/slab.h>
25 #include <linux/spinlock.h>
28 static struct sk_buff *esp4_gro_receive(struct list_head *head,
31 int offset = skb_gro_offset(skb);
32 struct xfrm_offload *xo;
37 if (!pskb_pull(skb, offset))
40 if (xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq) != 0)
43 xo = xfrm_offload(skb);
44 if (!xo || !(xo->flags & CRYPTO_DONE)) {
45 struct sec_path *sp = secpath_set(skb);
50 if (sp->len == XFRM_MAX_DEPTH)
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);
59 skb->mark = xfrm_smark_get(skb->mark, x);
61 sp->xvec[sp->len++] = x;
64 xo = xfrm_offload(skb);
69 xo->flags |= XFRM_GRO;
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;
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);
80 return ERR_PTR(-EINPROGRESS);
84 skb_push(skb, offset);
85 NAPI_GRO_CB(skb)->same_flow = 0;
86 NAPI_GRO_CB(skb)->flush = 1;
91 static void esp4_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
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;
98 skb_push(skb, -skb_network_offset(skb));
99 esph = ip_esp_hdr(skb);
100 *skb_mac_header(skb) = IPPROTO_ESP;
102 esph->spi = x->id.spi;
103 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
108 static struct sk_buff *xfrm4_tunnel_gso_segment(struct xfrm_state *x,
110 netdev_features_t features)
112 __skb_push(skb, skb->mac_len);
113 return skb_mac_gso_segment(skb, features);
116 static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x,
118 netdev_features_t features)
120 const struct net_offload *ops;
121 struct sk_buff *segs = ERR_PTR(-EINVAL);
122 struct xfrm_offload *xo = xfrm_offload(skb);
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);
132 static struct sk_buff *xfrm4_beet_gso_segment(struct xfrm_state *x,
134 netdev_features_t features)
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;
141 skb->transport_header += x->props.header_len;
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;
148 skb->transport_header += ph->hdrlen * 8;
151 skb->transport_header -= IPV4_BEET_PHMAXLEN;
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;
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);
170 static struct sk_buff *xfrm4_outer_mode_gso_segment(struct xfrm_state *x,
172 netdev_features_t features)
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);
180 return xfrm4_beet_gso_segment(x, skb, features);
183 return ERR_PTR(-EOPNOTSUPP);
186 static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
187 netdev_features_t features)
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);
197 return ERR_PTR(-EINVAL);
199 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
200 return ERR_PTR(-EINVAL);
202 sp = skb_sec_path(skb);
203 x = sp->xvec[sp->len - 1];
205 esph = ip_esp_hdr(skb);
207 if (esph->spi != x->id.spi)
208 return ERR_PTR(-EINVAL);
210 if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
211 return ERR_PTR(-EINVAL);
213 __skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
215 skb->encap_hdr_csum = 1;
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 |
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 |
226 xo->flags |= XFRM_GSO_SEGMENT;
228 return xfrm4_outer_mode_gso_segment(x, skb, esp_features);
231 static int esp_input_tail(struct xfrm_state *x, struct sk_buff *skb)
233 struct crypto_aead *aead = x->data;
234 struct xfrm_offload *xo = xfrm_offload(skb);
236 if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
239 if (!(xo->flags & CRYPTO_DONE))
240 skb->ip_summed = CHECKSUM_NONE;
242 return esp_input_done2(skb, 0);
245 static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features)
250 struct xfrm_offload *xo;
251 struct ip_esp_hdr *esph;
252 struct crypto_aead *aead;
254 bool hw_offload = true;
259 xo = xfrm_offload(skb);
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;
271 esp.proto = xo->proto;
273 /* skb is pure payload to encrypt */
276 alen = crypto_aead_authsize(aead);
279 /* XXX: Add support for tfc padding here. */
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;
286 esp.esph = ip_esp_hdr(skb);
289 if (!hw_offload || !skb_is_gso(skb)) {
290 esp.nfrags = esp_output_head(x, skb, &esp);
298 esph->spi = x->id.spi;
300 skb_push(skb, -skb_network_offset(skb));
302 if (xo->flags & XFRM_GSO_SEGMENT) {
303 esph->seq_no = htonl(seq);
305 if (!skb_is_gso(skb))
308 xo->seq.low += skb_shinfo(skb)->gso_segs;
311 esp.seqno = cpu_to_be64(seq + ((u64)xo->seq.hi << 32));
313 ip_hdr(skb)->tot_len = htons(skb->len);
314 ip_send_check(ip_hdr(skb));
317 if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
320 xo = xfrm_offload(skb);
324 xo->flags |= XFRM_XMIT;
328 err = esp_output_tail(x, skb, &esp);
337 static const struct net_offload esp4_offload = {
339 .gro_receive = esp4_gro_receive,
340 .gso_segment = esp4_gso_segment,
344 static const struct xfrm_type_offload esp_type_offload = {
345 .owner = THIS_MODULE,
346 .proto = IPPROTO_ESP,
347 .input_tail = esp_input_tail,
349 .encap = esp4_gso_encap,
352 static int __init esp4_offload_init(void)
354 if (xfrm_register_type_offload(&esp_type_offload, AF_INET) < 0) {
355 pr_info("%s: can't add xfrm type offload\n", __func__);
359 return inet_add_offload(&esp4_offload, IPPROTO_ESP);
362 static void __exit esp4_offload_exit(void)
364 xfrm_unregister_type_offload(&esp_type_offload, AF_INET);
365 inet_del_offload(&esp4_offload, IPPROTO_ESP);
368 module_init(esp4_offload_init);
369 module_exit(esp4_offload_exit);
370 MODULE_LICENSE("GPL");
371 MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
372 MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET, XFRM_PROTO_ESP);
373 MODULE_DESCRIPTION("IPV4 GSO/GRO offload support");