[linux-2.6-block.git] / net / ipv4 / esp4_offload.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * IPV4 GSO/GRO offload support
 * Linux INET implementation
 *
 * Copyright (C) 2016 secunet Security Networks AG
 * Author: Steffen Klassert <steffen.klassert@secunet.com>
 *
 * ESP GRO support
 */

#include <linux/skbuff.h>
#include <linux/init.h>
#include <net/protocol.h>
#include <crypto/aead.h>
#include <crypto/authenc.h>
#include <linux/err.h>
#include <linux/module.h>
#include <net/gro.h>
#include <net/ip.h>
#include <net/xfrm.h>
#include <net/esp.h>
#include <linux/scatterlist.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <net/udp.h>

static struct sk_buff *esp4_gro_receive(struct list_head *head,
					struct sk_buff *skb)
{
	int offset = skb_gro_offset(skb);
	struct xfrm_offload *xo;
	struct xfrm_state *x;
	__be32 seq;
	__be32 spi;

	if (!pskb_pull(skb, offset))
		return NULL;

	if (xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq) != 0)
		goto out;

	xo = xfrm_offload(skb);
	if (!xo || !(xo->flags & CRYPTO_DONE)) {
		struct sec_path *sp = secpath_set(skb);

		if (!sp)
			goto out;

		if (sp->len == XFRM_MAX_DEPTH)
			goto out_reset;

		x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
				      (xfrm_address_t *)&ip_hdr(skb)->daddr,
				      spi, IPPROTO_ESP, AF_INET);
		if (!x)
			goto out_reset;

		skb->mark = xfrm_smark_get(skb->mark, x);

		sp->xvec[sp->len++] = x;
		sp->olen++;

		xo = xfrm_offload(skb);
		if (!xo)
			goto out_reset;
	}

	xo->flags |= XFRM_GRO;

	XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;
	XFRM_SPI_SKB_CB(skb)->family = AF_INET;
	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
	XFRM_SPI_SKB_CB(skb)->seq = seq;

	/* We don't need to handle errors from xfrm_input, it does all
	 * the error handling and frees the resources on error. */
	xfrm_input(skb, IPPROTO_ESP, spi, -2);

	return ERR_PTR(-EINPROGRESS);
out_reset:
	secpath_reset(skb);
out:
	skb_push(skb, offset);
	NAPI_GRO_CB(skb)->same_flow = 0;
	NAPI_GRO_CB(skb)->flush = 1;

	return NULL;
}

static void esp4_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ip_esp_hdr *esph;
	struct iphdr *iph = ip_hdr(skb);
	struct xfrm_offload *xo = xfrm_offload(skb);
	int proto = iph->protocol;

	skb_push(skb, -skb_network_offset(skb));
	esph = ip_esp_hdr(skb);
	*skb_mac_header(skb) = IPPROTO_ESP;

	esph->spi = x->id.spi;
	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);

	xo->proto = proto;
}

static struct sk_buff *xfrm4_tunnel_gso_segment(struct xfrm_state *x,
						struct sk_buff *skb,
						netdev_features_t features)
{
	return skb_eth_gso_segment(skb, features, htons(ETH_P_IP));
}

static struct sk_buff *xfrm4_transport_gso_segment(struct xfrm_state *x,
						   struct sk_buff *skb,
						   netdev_features_t features)
{
	const struct net_offload *ops;
	struct sk_buff *segs = ERR_PTR(-EINVAL);
	struct xfrm_offload *xo = xfrm_offload(skb);

	skb->transport_header += x->props.header_len;
	ops = rcu_dereference(inet_offloads[xo->proto]);
	if (likely(ops && ops->callbacks.gso_segment))
		segs = ops->callbacks.gso_segment(skb, features);

	return segs;
}

static struct sk_buff *xfrm4_beet_gso_segment(struct xfrm_state *x,
					      struct sk_buff *skb,
					      netdev_features_t features)
{
	struct xfrm_offload *xo = xfrm_offload(skb);
	struct sk_buff *segs = ERR_PTR(-EINVAL);
	const struct net_offload *ops;
	u8 proto = xo->proto;

	skb->transport_header += x->props.header_len;

	if (x->sel.family != AF_INET6) {
		if (proto == IPPROTO_BEETPH) {
			struct ip_beet_phdr *ph =
				(struct ip_beet_phdr *)skb->data;

			skb->transport_header += ph->hdrlen * 8;
			proto = ph->nexthdr;
		} else {
			skb->transport_header -= IPV4_BEET_PHMAXLEN;
		}
	} else {
		__be16 frag;

		skb->transport_header +=
			ipv6_skip_exthdr(skb, 0, &proto, &frag);
		if (proto == IPPROTO_TCP)
			skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV4;
	}

	if (proto == IPPROTO_IPV6)
		skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP4;

	__skb_pull(skb, skb_transport_offset(skb));
	ops = rcu_dereference(inet_offloads[proto]);
	if (likely(ops && ops->callbacks.gso_segment))
		segs = ops->callbacks.gso_segment(skb, features);

	return segs;
}

static struct sk_buff *xfrm4_outer_mode_gso_segment(struct xfrm_state *x,
						    struct sk_buff *skb,
						    netdev_features_t features)
{
	switch (x->outer_mode.encap) {
	case XFRM_MODE_TUNNEL:
		return xfrm4_tunnel_gso_segment(x, skb, features);
	case XFRM_MODE_TRANSPORT:
		return xfrm4_transport_gso_segment(x, skb, features);
	case XFRM_MODE_BEET:
		return xfrm4_beet_gso_segment(x, skb, features);
	}

	return ERR_PTR(-EOPNOTSUPP);
}

static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
				        netdev_features_t features)
{
	struct xfrm_state *x;
	struct ip_esp_hdr *esph;
	struct crypto_aead *aead;
	netdev_features_t esp_features = features;
	struct xfrm_offload *xo = xfrm_offload(skb);
	struct sec_path *sp;

	if (!xo)
		return ERR_PTR(-EINVAL);

	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
		return ERR_PTR(-EINVAL);

	sp = skb_sec_path(skb);
	x = sp->xvec[sp->len - 1];
	aead = x->data;
	esph = ip_esp_hdr(skb);

	if (esph->spi != x->id.spi)
		return ERR_PTR(-EINVAL);

	if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
		return ERR_PTR(-EINVAL);

	__skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));

	skb->encap_hdr_csum = 1;

	if ((!(skb->dev->gso_partial_features & NETIF_F_HW_ESP) &&
	     !(features & NETIF_F_HW_ESP)) || x->xso.dev != skb->dev)
		esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK |
					    NETIF_F_SCTP_CRC);
	else if (!(features & NETIF_F_HW_ESP_TX_CSUM) &&
		 !(skb->dev->gso_partial_features & NETIF_F_HW_ESP_TX_CSUM))
		esp_features = features & ~(NETIF_F_CSUM_MASK |
					    NETIF_F_SCTP_CRC);

	xo->flags |= XFRM_GSO_SEGMENT;

	return xfrm4_outer_mode_gso_segment(x, skb, esp_features);
}

static int esp_input_tail(struct xfrm_state *x, struct sk_buff *skb)
{
	struct crypto_aead *aead = x->data;
	struct xfrm_offload *xo = xfrm_offload(skb);

	if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
		return -EINVAL;

	if (!(xo->flags & CRYPTO_DONE))
		skb->ip_summed = CHECKSUM_NONE;

	return esp_input_done2(skb, 0);
}

static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb,  netdev_features_t features)
{
	int err;
	int alen;
	int blksize;
	struct xfrm_offload *xo;
	struct ip_esp_hdr *esph;
	struct crypto_aead *aead;
	struct esp_info esp;
	bool hw_offload = true;
	__u32 seq;

	esp.inplace = true;

	xo = xfrm_offload(skb);

	if (!xo)
		return -EINVAL;

	if ((!(features & NETIF_F_HW_ESP) &&
	     !(skb->dev->gso_partial_features & NETIF_F_HW_ESP)) ||
	    x->xso.dev != skb->dev) {
		xo->flags |= CRYPTO_FALLBACK;
		hw_offload = false;
	}

	esp.proto = xo->proto;

	/* skb is pure payload to encrypt */

	aead = x->data;
	alen = crypto_aead_authsize(aead);

	esp.tfclen = 0;
	/* XXX: Add support for tfc padding here. */

	blksize = ALIGN(crypto_aead_blocksize(aead), 4);
	esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
	esp.plen = esp.clen - skb->len - esp.tfclen;
	esp.tailen = esp.tfclen + esp.plen + alen;

	esp.esph = ip_esp_hdr(skb);


	if (!hw_offload || !skb_is_gso(skb)) {
		esp.nfrags = esp_output_head(x, skb, &esp);
		if (esp.nfrags < 0)
			return esp.nfrags;
	}

	seq = xo->seq.low;

	esph = esp.esph;
	esph->spi = x->id.spi;

	skb_push(skb, -skb_network_offset(skb));

	if (xo->flags & XFRM_GSO_SEGMENT) {
		esph->seq_no = htonl(seq);

		if (!skb_is_gso(skb))
			xo->seq.low++;
		else
			xo->seq.low += skb_shinfo(skb)->gso_segs;
	}

	esp.seqno = cpu_to_be64(seq + ((u64)xo->seq.hi << 32));

	ip_hdr(skb)->tot_len = htons(skb->len);
	ip_send_check(ip_hdr(skb));

	if (hw_offload) {
		if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
			return -ENOMEM;

		xo = xfrm_offload(skb);
		if (!xo)
			return -EINVAL;

		xo->flags |= XFRM_XMIT;
		return 0;
	}

	err = esp_output_tail(x, skb, &esp);
	if (err)
		return err;

	secpath_reset(skb);

	return 0;
}

static const struct net_offload esp4_offload = {
	.callbacks = {
		.gro_receive = esp4_gro_receive,
		.gso_segment = esp4_gso_segment,
	},
};

static const struct xfrm_type_offload esp_type_offload = {
	.owner		= THIS_MODULE,
	.proto	     	= IPPROTO_ESP,
	.input_tail	= esp_input_tail,
	.xmit		= esp_xmit,
	.encap		= esp4_gso_encap,
};

static int __init esp4_offload_init(void)
{
	if (xfrm_register_type_offload(&esp_type_offload, AF_INET) < 0) {
		pr_info("%s: can't add xfrm type offload\n", __func__);
		return -EAGAIN;
	}

	return inet_add_offload(&esp4_offload, IPPROTO_ESP);
}

static void __exit esp4_offload_exit(void)
{
	xfrm_unregister_type_offload(&esp_type_offload, AF_INET);
	inet_del_offload(&esp4_offload, IPPROTO_ESP);
}

module_init(esp4_offload_init);
module_exit(esp4_offload_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET, XFRM_PROTO_ESP);
MODULE_DESCRIPTION("IPV4 GSO/GRO offload support");
Commit	Line	Data
75a6faf6	1	// SPDX-License-Identifier: GPL-2.0-only
7785bba2 SK	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	*
7785bba2 SK	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>
4721031c	19	#include <net/gro.h>
7785bba2 SK	20	#include <net/ip.h>
	21	#include <net/xfrm.h>
	22	#include <net/esp.h>
	23	#include <linux/scatterlist.h>
	24	#include <linux/kernel.h>
	25	#include <linux/slab.h>
	26	#include <linux/spinlock.h>
	27	#include <net/udp.h>
	28
d4546c25 DM	29	static struct sk_buff esp4_gro_receive(struct list_head head,
d4546c25 DM	30	struct sk_buff *skb)
7785bba2 SK	31	{
	32	int offset = skb_gro_offset(skb);
	33	struct xfrm_offload *xo;
	34	struct xfrm_state *x;
	35	__be32 seq;
	36	__be32 spi;
7785bba2	37
374d1b5a SK	38	if (!pskb_pull(skb, offset))
374d1b5a SK	39	return NULL;
7785bba2	40
335a2a1f	41	if (xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq) != 0)
7785bba2 SK	42	goto out;
7785bba2 SK	43
bcd1f8a4 SK	44	xo = xfrm_offload(skb);
bcd1f8a4 SK	45	if (!xo \|\| !(xo->flags & CRYPTO_DONE)) {
0ca64da1 FW	46	struct sec_path *sp = secpath_set(skb);
	47
	48	if (!sp)
bcd1f8a4	49	goto out;
7785bba2	50
0ca64da1	51	if (sp->len == XFRM_MAX_DEPTH)
6ed69184	52	goto out_reset;
7785bba2	53
bcd1f8a4 SK	54	x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
	55	(xfrm_address_t *)&ip_hdr(skb)->daddr,
	56	spi, IPPROTO_ESP, AF_INET);
	57	if (!x)
6ed69184	58	goto out_reset;
7785bba2	59
4e4362d2 UW	60	skb->mark = xfrm_smark_get(skb->mark, x);
4e4362d2 UW	61
0ca64da1 FW	62	sp->xvec[sp->len++] = x;
0ca64da1 FW	63	sp->olen++;
7785bba2	64
bcd1f8a4	65	xo = xfrm_offload(skb);
db87668a	66	if (!xo)
6ed69184	67	goto out_reset;
7785bba2	68	}
bcd1f8a4	69
7785bba2 SK	70	xo->flags \|= XFRM_GRO;
	71
	72	XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;
	73	XFRM_SPI_SKB_CB(skb)->family = AF_INET;
	74	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr);
	75	XFRM_SPI_SKB_CB(skb)->seq = seq;
	76
	77	/* We don't need to handle errors from xfrm_input, it does all
	78	* the error handling and frees the resources on error. */
	79	xfrm_input(skb, IPPROTO_ESP, spi, -2);
	80
	81	return ERR_PTR(-EINPROGRESS);
6ed69184 MJ	82	out_reset:
6ed69184 MJ	83	secpath_reset(skb);
7785bba2 SK	84	out:
	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
7862b405 SK	92	static 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
7613b92b FW	109	static struct sk_buff xfrm4_tunnel_gso_segment(struct xfrm_state x,
	110	struct sk_buff *skb,
	111	netdev_features_t features)
	112	{
23c7f8d7	113	return skb_eth_gso_segment(skb, features, htons(ETH_P_IP));
7613b92b FW	114	}
	115
	116	static 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
384a46ea XL	132	static 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;
6f297068	139	u8 proto = xo->proto;
384a46ea XL	140
	141	skb->transport_header += x->props.header_len;
	142
3ffb93ba XL	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 {
6f297068 XL	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;
384a46ea XL	160	}
384a46ea XL	161
053c8fdf SK	162	if (proto == IPPROTO_IPV6)
	163	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP4;
	164
384a46ea XL	165	__skb_pull(skb, skb_transport_offset(skb));
	166	ops = rcu_dereference(inet_offloads[proto]);
	167	if (likely(ops && ops->callbacks.gso_segment))
	168	segs = ops->callbacks.gso_segment(skb, features);
	169
	170	return segs;
	171	}
	172
7613b92b FW	173	static struct sk_buff xfrm4_outer_mode_gso_segment(struct xfrm_state x,
	174	struct sk_buff *skb,
	175	netdev_features_t features)
	176	{
c9500d7b	177	switch (x->outer_mode.encap) {
7613b92b FW	178	case XFRM_MODE_TUNNEL:
	179	return xfrm4_tunnel_gso_segment(x, skb, features);
	180	case XFRM_MODE_TRANSPORT:
	181	return xfrm4_transport_gso_segment(x, skb, features);
384a46ea XL	182	case XFRM_MODE_BEET:
384a46ea XL	183	return xfrm4_beet_gso_segment(x, skb, features);
7613b92b FW	184	}
	185
	186	return ERR_PTR(-EOPNOTSUPP);
	187	}
	188
7862b405 SK	189	static struct sk_buff esp4_gso_segment(struct sk_buff skb,
	190	netdev_features_t features)
	191	{
7862b405 SK	192	struct xfrm_state *x;
	193	struct ip_esp_hdr *esph;
	194	struct crypto_aead *aead;
7862b405 SK	195	netdev_features_t esp_features = features;
7862b405 SK	196	struct xfrm_offload *xo = xfrm_offload(skb);
2294be0f	197	struct sec_path *sp;
7862b405 SK	198
7862b405 SK	199	if (!xo)
3dca3f38	200	return ERR_PTR(-EINVAL);
7862b405	201
121d57af	202	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
5ca11440	203	return ERR_PTR(-EINVAL);
7862b405	204
2294be0f FW	205	sp = skb_sec_path(skb);
2294be0f FW	206	x = sp->xvec[sp->len - 1];
7862b405 SK	207	aead = x->data;
	208	esph = ip_esp_hdr(skb);
	209
	210	if (esph->spi != x->id.spi)
3dca3f38	211	return ERR_PTR(-EINVAL);
7862b405 SK	212
7862b405 SK	213	if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
3dca3f38	214	return ERR_PTR(-EINVAL);
7862b405 SK	215
	216	__skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
	217
	218	skb->encap_hdr_csum = 1;
	219
65fd2c2a BP	220	if ((!(skb->dev->gso_partial_features & NETIF_F_HW_ESP) &&
65fd2c2a BP	221	!(features & NETIF_F_HW_ESP)) \|\| x->xso.dev != skb->dev)
154deab6 XL	222	esp_features = features & ~(NETIF_F_SG \| NETIF_F_CSUM_MASK \|
154deab6 XL	223	NETIF_F_SCTP_CRC);
65fd2c2a BP	224	else if (!(features & NETIF_F_HW_ESP_TX_CSUM) &&
65fd2c2a BP	225	!(skb->dev->gso_partial_features & NETIF_F_HW_ESP_TX_CSUM))
154deab6 XL	226	esp_features = features & ~(NETIF_F_CSUM_MASK \|
154deab6 XL	227	NETIF_F_SCTP_CRC);
7862b405	228
3dca3f38	229	xo->flags \|= XFRM_GSO_SEGMENT;
7862b405	230
7613b92b	231	return xfrm4_outer_mode_gso_segment(x, skb, esp_features);
7862b405 SK	232	}
7862b405 SK	233
fca11ebd SK	234	static int esp_input_tail(struct xfrm_state x, struct sk_buff skb)
	235	{
	236	struct crypto_aead *aead = x->data;
ec9567a9	237	struct xfrm_offload *xo = xfrm_offload(skb);
fca11ebd SK	238
	239	if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
	240	return -EINVAL;
	241
ec9567a9 IT	242	if (!(xo->flags & CRYPTO_DONE))
ec9567a9 IT	243	skb->ip_summed = CHECKSUM_NONE;
fca11ebd SK	244
	245	return esp_input_done2(skb, 0);
	246	}
	247
	248	static int esp_xmit(struct xfrm_state x, struct sk_buff skb, netdev_features_t features)
	249	{
	250	int err;
	251	int alen;
	252	int blksize;
	253	struct xfrm_offload *xo;
	254	struct ip_esp_hdr *esph;
	255	struct crypto_aead *aead;
	256	struct esp_info esp;
	257	bool hw_offload = true;
3dca3f38	258	__u32 seq;
fca11ebd SK	259
	260	esp.inplace = true;
	261
	262	xo = xfrm_offload(skb);
	263
	264	if (!xo)
	265	return -EINVAL;
	266
65fd2c2a BP	267	if ((!(features & NETIF_F_HW_ESP) &&
	268	!(skb->dev->gso_partial_features & NETIF_F_HW_ESP)) \|\|
	269	x->xso.dev != skb->dev) {
fca11ebd SK	270	xo->flags \|= CRYPTO_FALLBACK;
	271	hw_offload = false;
	272	}
	273
	274	esp.proto = xo->proto;
	275
	276	/* skb is pure payload to encrypt */
	277
	278	aead = x->data;
	279	alen = crypto_aead_authsize(aead);
	280
	281	esp.tfclen = 0;
	282	/* XXX: Add support for tfc padding here. */
	283
	284	blksize = ALIGN(crypto_aead_blocksize(aead), 4);
	285	esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
	286	esp.plen = esp.clen - skb->len - esp.tfclen;
	287	esp.tailen = esp.tfclen + esp.plen + alen;
	288
	289	esp.esph = ip_esp_hdr(skb);
	290
	291
0c87b1ac	292	if (!hw_offload \|\| !skb_is_gso(skb)) {
fca11ebd SK	293	esp.nfrags = esp_output_head(x, skb, &esp);
	294	if (esp.nfrags < 0)
	295	return esp.nfrags;
	296	}
	297
3dca3f38 SK	298	seq = xo->seq.low;
3dca3f38 SK	299
fca11ebd SK	300	esph = esp.esph;
	301	esph->spi = x->id.spi;
	302
	303	skb_push(skb, -skb_network_offset(skb));
	304
	305	if (xo->flags & XFRM_GSO_SEGMENT) {
3dca3f38 SK	306	esph->seq_no = htonl(seq);
	307
	308	if (!skb_is_gso(skb))
	309	xo->seq.low++;
	310	else
	311	xo->seq.low += skb_shinfo(skb)->gso_segs;
fca11ebd SK	312	}
fca11ebd SK	313
3dca3f38 SK	314	esp.seqno = cpu_to_be64(seq + ((u64)xo->seq.hi << 32));
	315
	316	ip_hdr(skb)->tot_len = htons(skb->len);
	317	ip_send_check(ip_hdr(skb));
	318
c7dbf4c0 SK	319	if (hw_offload) {
	320	if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
	321	return -ENOMEM;
	322
	323	xo = xfrm_offload(skb);
	324	if (!xo)
	325	return -EINVAL;
	326
	327	xo->flags \|= XFRM_XMIT;
fca11ebd	328	return 0;
c7dbf4c0	329	}
fca11ebd	330
fca11ebd	331	err = esp_output_tail(x, skb, &esp);
4ff0308f	332	if (err)
fca11ebd SK	333	return err;
	334
	335	secpath_reset(skb);
	336
	337	return 0;
	338	}
	339
7785bba2 SK	340	static const struct net_offload esp4_offload = {
	341	.callbacks = {
	342	.gro_receive = esp4_gro_receive,
7862b405	343	.gso_segment = esp4_gso_segment,
7785bba2 SK	344	},
	345	};
	346
fca11ebd	347	static const struct xfrm_type_offload esp_type_offload = {
fca11ebd SK	348	.owner = THIS_MODULE,
	349	.proto = IPPROTO_ESP,
	350	.input_tail = esp_input_tail,
	351	.xmit = esp_xmit,
7862b405	352	.encap = esp4_gso_encap,
fca11ebd SK	353	};
fca11ebd SK	354
7785bba2 SK	355	static int __init esp4_offload_init(void)
7785bba2 SK	356	{
fca11ebd SK	357	if (xfrm_register_type_offload(&esp_type_offload, AF_INET) < 0) {
	358	pr_info("%s: can't add xfrm type offload\n", __func__);
	359	return -EAGAIN;
	360	}
	361
7785bba2 SK	362	return inet_add_offload(&esp4_offload, IPPROTO_ESP);
	363	}
	364
	365	static void __exit esp4_offload_exit(void)
	366	{
4f518e80	367	xfrm_unregister_type_offload(&esp_type_offload, AF_INET);
7785bba2 SK	368	inet_del_offload(&esp4_offload, IPPROTO_ESP);
	369	}
	370
	371	module_init(esp4_offload_init);
	372	module_exit(esp4_offload_exit);
	373	MODULE_LICENSE("GPL");
	374	MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
ffdb5211	375	MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET, XFRM_PROTO_ESP);
67c20de3	376	MODULE_DESCRIPTION("IPV4 GSO/GRO offload support");