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>
24 #include <linux/scatterlist.h>
25 #include <linux/kernel.h>
26 #include <linux/slab.h>
27 #include <linux/spinlock.h>
30 static struct sk_buff *esp4_gro_receive(struct list_head *head,
33 int offset = skb_gro_offset(skb);
34 struct xfrm_offload *xo;
40 if (!pskb_pull(skb, offset))
43 if (xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq) != 0)
46 xo = xfrm_offload(skb);
47 if (!xo || !(xo->flags & CRYPTO_DONE)) {
48 struct sec_path *sp = secpath_set(skb);
53 if (sp->len == XFRM_MAX_DEPTH)
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);
62 skb->mark = xfrm_smark_get(skb->mark, x);
64 sp->xvec[sp->len++] = x;
67 xo = xfrm_offload(skb);
72 xo->flags |= XFRM_GRO;
74 if (NAPI_GRO_CB(skb)->proto == IPPROTO_UDP)
75 encap_type = UDP_ENCAP_ESPINUDP;
77 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;
78 XFRM_SPI_SKB_CB(skb)->family = AF_INET;
79 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
80 XFRM_SPI_SKB_CB(skb)->seq = seq;
82 /* We don't need to handle errors from xfrm_input, it does all
83 * the error handling and frees the resources on error. */
84 xfrm_input(skb, IPPROTO_ESP, spi, encap_type);
86 return ERR_PTR(-EINPROGRESS);
90 skb_push(skb, offset);
91 NAPI_GRO_CB(skb)->same_flow = 0;
92 NAPI_GRO_CB(skb)->flush = 1;
97 static void esp4_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
99 struct ip_esp_hdr *esph;
100 struct iphdr *iph = ip_hdr(skb);
101 struct xfrm_offload *xo = xfrm_offload(skb);
102 int proto = iph->protocol;
104 skb_push(skb, -skb_network_offset(skb));
105 esph = ip_esp_hdr(skb);
106 *skb_mac_header(skb) = IPPROTO_ESP;
108 esph->spi = x->id.spi;
109 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
114 static struct sk_buff *xfrm4_tunnel_gso_segment(struct xfrm_state *x,
116 netdev_features_t features)
118 __be16 type = x->inner_mode.family == AF_INET6 ? htons(ETH_P_IPV6)
121 return skb_eth_gso_segment(skb, features, type);
124 static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x,
126 netdev_features_t features)
128 const struct net_offload *ops;
129 struct sk_buff *segs = ERR_PTR(-EINVAL);
130 struct xfrm_offload *xo = xfrm_offload(skb);
132 skb->transport_header += x->props.header_len;
133 ops = rcu_dereference(inet_offloads[xo->proto]);
134 if (likely(ops && ops->callbacks.gso_segment))
135 segs = ops->callbacks.gso_segment(skb, features);
140 static struct sk_buff *xfrm4_beet_gso_segment(struct xfrm_state *x,
142 netdev_features_t features)
144 struct xfrm_offload *xo = xfrm_offload(skb);
145 struct sk_buff *segs = ERR_PTR(-EINVAL);
146 const struct net_offload *ops;
147 u8 proto = xo->proto;
149 skb->transport_header += x->props.header_len;
151 if (x->sel.family != AF_INET6) {
152 if (proto == IPPROTO_BEETPH) {
153 struct ip_beet_phdr *ph =
154 (struct ip_beet_phdr *)skb->data;
156 skb->transport_header += ph->hdrlen * 8;
159 skb->transport_header -= IPV4_BEET_PHMAXLEN;
164 skb->transport_header +=
165 ipv6_skip_exthdr(skb, 0, &proto, &frag);
166 if (proto == IPPROTO_TCP)
167 skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4;
170 if (proto == IPPROTO_IPV6)
171 skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;
173 __skb_pull(skb, skb_transport_offset(skb));
174 ops = rcu_dereference(inet_offloads[proto]);
175 if (likely(ops && ops->callbacks.gso_segment))
176 segs = ops->callbacks.gso_segment(skb, features);
181 static struct sk_buff *xfrm4_outer_mode_gso_segment(struct xfrm_state *x,
183 netdev_features_t features)
185 switch (x->outer_mode.encap) {
186 case XFRM_MODE_TUNNEL:
187 return xfrm4_tunnel_gso_segment(x, skb, features);
188 case XFRM_MODE_TRANSPORT:
189 return xfrm4_transport_gso_segment(x, skb, features);
191 return xfrm4_beet_gso_segment(x, skb, features);
194 return ERR_PTR(-EOPNOTSUPP);
197 static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
198 netdev_features_t features)
200 struct xfrm_state *x;
201 struct ip_esp_hdr *esph;
202 struct crypto_aead *aead;
203 netdev_features_t esp_features = features;
204 struct xfrm_offload *xo = xfrm_offload(skb);
208 return ERR_PTR(-EINVAL);
210 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
211 return ERR_PTR(-EINVAL);
213 sp = skb_sec_path(skb);
214 x = sp->xvec[sp->len - 1];
216 esph = ip_esp_hdr(skb);
218 if (esph->spi != x->id.spi)
219 return ERR_PTR(-EINVAL);
221 if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
222 return ERR_PTR(-EINVAL);
224 __skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
226 skb->encap_hdr_csum = 1;
228 if ((!(skb->dev->gso_partial_features & NETIF_F_HW_ESP) &&
229 !(features & NETIF_F_HW_ESP)) || x->xso.dev != skb->dev)
230 esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK |
232 else if (!(features & NETIF_F_HW_ESP_TX_CSUM) &&
233 !(skb->dev->gso_partial_features & NETIF_F_HW_ESP_TX_CSUM))
234 esp_features = features & ~(NETIF_F_CSUM_MASK |
237 xo->flags |= XFRM_GSO_SEGMENT;
239 return xfrm4_outer_mode_gso_segment(x, skb, esp_features);
242 static int esp_input_tail(struct xfrm_state *x, struct sk_buff *skb)
244 struct crypto_aead *aead = x->data;
245 struct xfrm_offload *xo = xfrm_offload(skb);
247 if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
250 if (!(xo->flags & CRYPTO_DONE))
251 skb->ip_summed = CHECKSUM_NONE;
253 return esp_input_done2(skb, 0);
256 static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features)
261 struct xfrm_offload *xo;
262 struct ip_esp_hdr *esph;
263 struct crypto_aead *aead;
265 bool hw_offload = true;
270 xo = xfrm_offload(skb);
275 if ((!(features & NETIF_F_HW_ESP) &&
276 !(skb->dev->gso_partial_features & NETIF_F_HW_ESP)) ||
277 x->xso.dev != skb->dev) {
278 xo->flags |= CRYPTO_FALLBACK;
282 esp.proto = xo->proto;
284 /* skb is pure payload to encrypt */
287 alen = crypto_aead_authsize(aead);
290 /* XXX: Add support for tfc padding here. */
292 blksize = ALIGN(crypto_aead_blocksize(aead), 4);
293 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
294 esp.plen = esp.clen - skb->len - esp.tfclen;
295 esp.tailen = esp.tfclen + esp.plen + alen;
297 esp.esph = ip_esp_hdr(skb);
300 if (!hw_offload || !skb_is_gso(skb)) {
301 esp.nfrags = esp_output_head(x, skb, &esp);
309 esph->spi = x->id.spi;
311 skb_push(skb, -skb_network_offset(skb));
313 if (xo->flags & XFRM_GSO_SEGMENT) {
314 esph->seq_no = htonl(seq);
316 if (!skb_is_gso(skb))
319 xo->seq.low += skb_shinfo(skb)->gso_segs;
322 if (xo->seq.low < seq)
325 esp.seqno = cpu_to_be64(seq + ((u64)xo->seq.hi << 32));
327 ip_hdr(skb)->tot_len = htons(skb->len);
328 ip_send_check(ip_hdr(skb));
331 if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
334 xo = xfrm_offload(skb);
338 xo->flags |= XFRM_XMIT;
342 err = esp_output_tail(x, skb, &esp);
348 if (skb_needs_linearize(skb, skb->dev->features) &&
349 __skb_linearize(skb))
354 static const struct net_offload esp4_offload = {
356 .gro_receive = esp4_gro_receive,
357 .gso_segment = esp4_gso_segment,
361 static const struct xfrm_type_offload esp_type_offload = {
362 .owner = THIS_MODULE,
363 .proto = IPPROTO_ESP,
364 .input_tail = esp_input_tail,
366 .encap = esp4_gso_encap,
369 static int __init esp4_offload_init(void)
371 if (xfrm_register_type_offload(&esp_type_offload, AF_INET) < 0) {
372 pr_info("%s: can't add xfrm type offload\n", __func__);
376 return inet_add_offload(&esp4_offload, IPPROTO_ESP);
379 static void __exit esp4_offload_exit(void)
381 xfrm_unregister_type_offload(&esp_type_offload, AF_INET);
382 inet_del_offload(&esp4_offload, IPPROTO_ESP);
385 module_init(esp4_offload_init);
386 module_exit(esp4_offload_exit);
387 MODULE_LICENSE("GPL");
388 MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
389 MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET, XFRM_PROTO_ESP);
390 MODULE_DESCRIPTION("IPV4 GSO/GRO offload support");