[linux-2.6-block.git] / net / ipv6 / esp6_offload.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * IPV6 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/ip6_route.h>
#include <net/ipv6.h>
#include <linux/icmpv6.h>

static __u16 esp6_nexthdr_esp_offset(struct ipv6hdr *ipv6_hdr, int nhlen)
{
	int off = sizeof(struct ipv6hdr);
	struct ipv6_opt_hdr *exthdr;

	if (likely(ipv6_hdr->nexthdr == NEXTHDR_ESP))
		return offsetof(struct ipv6hdr, nexthdr);

	while (off < nhlen) {
		exthdr = (void *)ipv6_hdr + off;
		if (exthdr->nexthdr == NEXTHDR_ESP)
			return off;

		off += ipv6_optlen(exthdr);
	}

	return 0;
}

static struct sk_buff *esp6_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;
	int nhoff;
	int err;

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

	if ((err = 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 *)&ipv6_hdr(skb)->daddr,
				      spi, IPPROTO_ESP, AF_INET6);
		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;

	nhoff = esp6_nexthdr_esp_offset(ipv6_hdr(skb), offset);
	if (!nhoff)
		goto out;

	IP6CB(skb)->nhoff = nhoff;
	XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL;
	XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, 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 esp6_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
{
	struct ip_esp_hdr *esph;
	struct ipv6hdr *iph = ipv6_hdr(skb);
	struct xfrm_offload *xo = xfrm_offload(skb);
	u8 proto = iph->nexthdr;

	skb_push(skb, -skb_network_offset(skb));

	if (x->outer_mode.encap == XFRM_MODE_TRANSPORT) {
		__be16 frag;

		ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &proto, &frag);
	}

	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 *xfrm6_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_IPV6));
}

static struct sk_buff *xfrm6_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(inet6_offloads[xo->proto]);
	if (likely(ops && ops->callbacks.gso_segment))
		segs = ops->callbacks.gso_segment(skb, features);

	return segs;
}

static struct sk_buff *xfrm6_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) {
		skb->transport_header -=
			(sizeof(struct ipv6hdr) - sizeof(struct iphdr));

		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;
		}

		if (proto == IPPROTO_TCP)
			skb_shinfo(skb)->gso_type |= SKB_GSO_TCPV6;
	} else {
		__be16 frag;

		skb->transport_header +=
			ipv6_skip_exthdr(skb, 0, &proto, &frag);
	}

	if (proto == IPPROTO_IPIP)
		skb_shinfo(skb)->gso_type |= SKB_GSO_IPXIP6;

	__skb_pull(skb, skb_transport_offset(skb));
	ops = rcu_dereference(inet6_offloads[proto]);
	if (likely(ops && ops->callbacks.gso_segment))
		segs = ops->callbacks.gso_segment(skb, features);

	return segs;
}

static struct sk_buff *xfrm6_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 xfrm6_tunnel_gso_segment(x, skb, features);
	case XFRM_MODE_TRANSPORT:
		return xfrm6_transport_gso_segment(x, skb, features);
	case XFRM_MODE_BEET:
		return xfrm6_beet_gso_segment(x, skb, features);
	}

	return ERR_PTR(-EOPNOTSUPP);
}

static struct sk_buff *esp6_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 (!(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))
		esp_features = features & ~(NETIF_F_CSUM_MASK |
					    NETIF_F_SCTP_CRC);

	xo->flags |= XFRM_GSO_SEGMENT;

	return xfrm6_outer_mode_gso_segment(x, skb, esp_features);
}

static int esp6_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 esp6_input_done2(skb, 0);
}

static int esp6_xmit(struct xfrm_state *x, struct sk_buff *skb,  netdev_features_t features)
{
	int len;
	int err;
	int alen;
	int blksize;
	struct xfrm_offload *xo;
	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) || 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;

	if (!hw_offload || !skb_is_gso(skb)) {
		esp.nfrags = esp6_output_head(x, skb, &esp);
		if (esp.nfrags < 0)
			return esp.nfrags;
	}

	seq = xo->seq.low;

	esp.esph = ip_esp_hdr(skb);
	esp.esph->spi = x->id.spi;

	skb_push(skb, -skb_network_offset(skb));

	if (xo->flags & XFRM_GSO_SEGMENT) {
		esp.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(xo->seq.low + ((u64)xo->seq.hi << 32));

	len = skb->len - sizeof(struct ipv6hdr);
	if (len > IPV6_MAXPLEN)
		len = 0;

	ipv6_hdr(skb)->payload_len = htons(len);

	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 = esp6_output_tail(x, skb, &esp);
	if (err)
		return err;

	secpath_reset(skb);

	return 0;
}

static const struct net_offload esp6_offload = {
	.callbacks = {
		.gro_receive = esp6_gro_receive,
		.gso_segment = esp6_gso_segment,
	},
};

static const struct xfrm_type_offload esp6_type_offload = {
	.owner		= THIS_MODULE,
	.proto	     	= IPPROTO_ESP,
	.input_tail	= esp6_input_tail,
	.xmit		= esp6_xmit,
	.encap		= esp6_gso_encap,
};

static int __init esp6_offload_init(void)
{
	if (xfrm_register_type_offload(&esp6_type_offload, AF_INET6) < 0) {
		pr_info("%s: can't add xfrm type offload\n", __func__);
		return -EAGAIN;
	}

	return inet6_add_offload(&esp6_offload, IPPROTO_ESP);
}

static void __exit esp6_offload_exit(void)
{
	xfrm_unregister_type_offload(&esp6_type_offload, AF_INET6);
	inet6_del_offload(&esp6_offload, IPPROTO_ESP);
}

module_init(esp6_offload_init);
module_exit(esp6_offload_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET6, XFRM_PROTO_ESP);
MODULE_DESCRIPTION("IPV6 GSO/GRO offload support");
Commit	Line	Data
75a6faf6	1	// SPDX-License-Identifier: GPL-2.0-only
7785bba2 SK	2	/*
	3	* IPV6 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/ip6_route.h>
	28	#include <net/ipv6.h>
	29	#include <linux/icmpv6.h>
	30
ca3a1b85 YK	31	static __u16 esp6_nexthdr_esp_offset(struct ipv6hdr *ipv6_hdr, int nhlen)
	32	{
	33	int off = sizeof(struct ipv6hdr);
	34	struct ipv6_opt_hdr *exthdr;
	35
	36	if (likely(ipv6_hdr->nexthdr == NEXTHDR_ESP))
	37	return offsetof(struct ipv6hdr, nexthdr);
	38
	39	while (off < nhlen) {
	40	exthdr = (void *)ipv6_hdr + off;
	41	if (exthdr->nexthdr == NEXTHDR_ESP)
	42	return off;
	43
	44	off += ipv6_optlen(exthdr);
	45	}
	46
	47	return 0;
	48	}
	49
d4546c25 DM	50	static struct sk_buff esp6_gro_receive(struct list_head head,
d4546c25 DM	51	struct sk_buff *skb)
7785bba2 SK	52	{
	53	int offset = skb_gro_offset(skb);
	54	struct xfrm_offload *xo;
	55	struct xfrm_state *x;
	56	__be32 seq;
	57	__be32 spi;
ca3a1b85	58	int nhoff;
7785bba2 SK	59	int err;
7785bba2 SK	60
374d1b5a SK	61	if (!pskb_pull(skb, offset))
374d1b5a SK	62	return NULL;
7785bba2 SK	63
	64	if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0)
	65	goto out;
	66
bcd1f8a4 SK	67	xo = xfrm_offload(skb);
bcd1f8a4 SK	68	if (!xo \|\| !(xo->flags & CRYPTO_DONE)) {
0ca64da1 FW	69	struct sec_path *sp = secpath_set(skb);
	70
	71	if (!sp)
bcd1f8a4	72	goto out;
7785bba2	73
0ca64da1	74	if (sp->len == XFRM_MAX_DEPTH)
6ed69184	75	goto out_reset;
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)
6ed69184	81	goto out_reset;
7785bba2	82
4e4362d2 UW	83	skb->mark = xfrm_smark_get(skb->mark, x);
4e4362d2 UW	84
0ca64da1 FW	85	sp->xvec[sp->len++] = x;
0ca64da1 FW	86	sp->olen++;
7785bba2	87
bcd1f8a4	88	xo = xfrm_offload(skb);
db87668a	89	if (!xo)
6ed69184	90	goto out_reset;
7785bba2	91	}
bcd1f8a4	92
7785bba2 SK	93	xo->flags \|= XFRM_GRO;
7785bba2 SK	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);
6ed69184 MJ	110	out_reset:
6ed69184 MJ	111	secpath_reset(skb);
7785bba2 SK	112	out:
	113	skb_push(skb, offset);
	114	NAPI_GRO_CB(skb)->same_flow = 0;
	115	NAPI_GRO_CB(skb)->flush = 1;
	116
	117	return NULL;
	118	}
	119
7862b405 SK	120	static void esp6_gso_encap(struct xfrm_state x, struct sk_buff skb)
	121	{
	122	struct ip_esp_hdr *esph;
	123	struct ipv6hdr *iph = ipv6_hdr(skb);
	124	struct xfrm_offload *xo = xfrm_offload(skb);
3c96ec56	125	u8 proto = iph->nexthdr;
7862b405 SK	126
7862b405 SK	127	skb_push(skb, -skb_network_offset(skb));
3c96ec56 XL	128
	129	if (x->outer_mode.encap == XFRM_MODE_TRANSPORT) {
	130	__be16 frag;
	131
	132	ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &proto, &frag);
	133	}
	134
7862b405 SK	135	esph = ip_esp_hdr(skb);
	136	*skb_mac_header(skb) = IPPROTO_ESP;
	137
	138	esph->spi = x->id.spi;
	139	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
	140
	141	xo->proto = proto;
	142	}
	143
7613b92b FW	144	static struct sk_buff xfrm6_tunnel_gso_segment(struct xfrm_state x,
	145	struct sk_buff *skb,
	146	netdev_features_t features)
	147	{
23c7f8d7	148	return skb_eth_gso_segment(skb, features, htons(ETH_P_IPV6));
7613b92b FW	149	}
	150
	151	static struct sk_buff xfrm6_transport_gso_segment(struct xfrm_state x,
	152	struct sk_buff *skb,
	153	netdev_features_t features)
	154	{
	155	const struct net_offload *ops;
	156	struct sk_buff *segs = ERR_PTR(-EINVAL);
	157	struct xfrm_offload *xo = xfrm_offload(skb);
	158
	159	skb->transport_header += x->props.header_len;
	160	ops = rcu_dereference(inet6_offloads[xo->proto]);
	161	if (likely(ops && ops->callbacks.gso_segment))
	162	segs = ops->callbacks.gso_segment(skb, features);
	163
	164	return segs;
	165	}
	166
7f9e40eb XL	167	static struct sk_buff xfrm6_beet_gso_segment(struct xfrm_state x,
	168	struct sk_buff *skb,
	169	netdev_features_t features)
	170	{
	171	struct xfrm_offload *xo = xfrm_offload(skb);
	172	struct sk_buff *segs = ERR_PTR(-EINVAL);
	173	const struct net_offload *ops;
25a44ae9	174	u8 proto = xo->proto;
7f9e40eb XL	175
	176	skb->transport_header += x->props.header_len;
	177
7f9e40eb XL	178	if (x->sel.family != AF_INET6) {
	179	skb->transport_header -=
	180	(sizeof(struct ipv6hdr) - sizeof(struct iphdr));
	181
56b1b7c6 XL	182	if (proto == IPPROTO_BEETPH) {
	183	struct ip_beet_phdr *ph =
	184	(struct ip_beet_phdr *)skb->data;
	185
	186	skb->transport_header += ph->hdrlen * 8;
	187	proto = ph->nexthdr;
	188	} else {
	189	skb->transport_header -= IPV4_BEET_PHMAXLEN;
	190	}
7f9e40eb	191
7f9e40eb XL	192	if (proto == IPPROTO_TCP)
7f9e40eb XL	193	skb_shinfo(skb)->gso_type \|= SKB_GSO_TCPV6;
56b1b7c6	194	} else {
25a44ae9 XL	195	__be16 frag;
	196
	197	skb->transport_header +=
	198	ipv6_skip_exthdr(skb, 0, &proto, &frag);
7f9e40eb XL	199	}
7f9e40eb XL	200
053c8fdf SK	201	if (proto == IPPROTO_IPIP)
	202	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP6;
	203
7f9e40eb XL	204	__skb_pull(skb, skb_transport_offset(skb));
	205	ops = rcu_dereference(inet6_offloads[proto]);
	206	if (likely(ops && ops->callbacks.gso_segment))
	207	segs = ops->callbacks.gso_segment(skb, features);
	208
	209	return segs;
	210	}
	211
7613b92b FW	212	static struct sk_buff xfrm6_outer_mode_gso_segment(struct xfrm_state x,
	213	struct sk_buff *skb,
	214	netdev_features_t features)
	215	{
c9500d7b	216	switch (x->outer_mode.encap) {
7613b92b FW	217	case XFRM_MODE_TUNNEL:
	218	return xfrm6_tunnel_gso_segment(x, skb, features);
	219	case XFRM_MODE_TRANSPORT:
	220	return xfrm6_transport_gso_segment(x, skb, features);
7f9e40eb XL	221	case XFRM_MODE_BEET:
7f9e40eb XL	222	return xfrm6_beet_gso_segment(x, skb, features);
7613b92b FW	223	}
	224
	225	return ERR_PTR(-EOPNOTSUPP);
	226	}
	227
7862b405 SK	228	static struct sk_buff esp6_gso_segment(struct sk_buff skb,
	229	netdev_features_t features)
	230	{
7862b405 SK	231	struct xfrm_state *x;
	232	struct ip_esp_hdr *esph;
	233	struct crypto_aead *aead;
7862b405 SK	234	netdev_features_t esp_features = features;
7862b405 SK	235	struct xfrm_offload *xo = xfrm_offload(skb);
2294be0f	236	struct sec_path *sp;
7862b405	237
ffa6f571	238	if (!xo)
3dca3f38	239	return ERR_PTR(-EINVAL);
7862b405	240
121d57af	241	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
5ca11440	242	return ERR_PTR(-EINVAL);
7862b405	243
2294be0f FW	244	sp = skb_sec_path(skb);
2294be0f FW	245	x = sp->xvec[sp->len - 1];
7862b405 SK	246	aead = x->data;
	247	esph = ip_esp_hdr(skb);
	248
	249	if (esph->spi != x->id.spi)
3dca3f38	250	return ERR_PTR(-EINVAL);
7862b405 SK	251
7862b405 SK	252	if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
3dca3f38	253	return ERR_PTR(-EINVAL);
7862b405 SK	254
	255	__skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
	256
	257	skb->encap_hdr_csum = 1;
	258
fcb662de	259	if (!(features & NETIF_F_HW_ESP) \|\| x->xso.dev != skb->dev)
154deab6 XL	260	esp_features = features & ~(NETIF_F_SG \| NETIF_F_CSUM_MASK \|
154deab6 XL	261	NETIF_F_SCTP_CRC);
5211fcfb	262	else if (!(features & NETIF_F_HW_ESP_TX_CSUM))
154deab6 XL	263	esp_features = features & ~(NETIF_F_CSUM_MASK \|
154deab6 XL	264	NETIF_F_SCTP_CRC);
7862b405	265
3dca3f38	266	xo->flags \|= XFRM_GSO_SEGMENT;
7862b405	267
7613b92b	268	return xfrm6_outer_mode_gso_segment(x, skb, esp_features);
7862b405 SK	269	}
7862b405 SK	270
383d0350 SK	271	static int esp6_input_tail(struct xfrm_state x, struct sk_buff skb)
	272	{
	273	struct crypto_aead *aead = x->data;
e51a6472	274	struct xfrm_offload *xo = xfrm_offload(skb);
383d0350 SK	275
	276	if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
	277	return -EINVAL;
	278
e51a6472 IT	279	if (!(xo->flags & CRYPTO_DONE))
e51a6472 IT	280	skb->ip_summed = CHECKSUM_NONE;
383d0350 SK	281
	282	return esp6_input_done2(skb, 0);
	283	}
	284
	285	static int esp6_xmit(struct xfrm_state x, struct sk_buff skb, netdev_features_t features)
	286	{
3dca3f38	287	int len;
383d0350 SK	288	int err;
	289	int alen;
	290	int blksize;
	291	struct xfrm_offload *xo;
383d0350 SK	292	struct crypto_aead *aead;
	293	struct esp_info esp;
	294	bool hw_offload = true;
3dca3f38	295	__u32 seq;
383d0350 SK	296
	297	esp.inplace = true;
	298
	299	xo = xfrm_offload(skb);
	300
	301	if (!xo)
	302	return -EINVAL;
	303
fcb662de	304	if (!(features & NETIF_F_HW_ESP) \|\| x->xso.dev != skb->dev) {
383d0350	305	xo->flags \|= CRYPTO_FALLBACK;
8f92e03e	306	hw_offload = false;
383d0350 SK	307	}
	308
	309	esp.proto = xo->proto;
	310
	311	/* skb is pure payload to encrypt */
	312
	313	aead = x->data;
	314	alen = crypto_aead_authsize(aead);
	315
	316	esp.tfclen = 0;
	317	/* XXX: Add support for tfc padding here. */
	318
	319	blksize = ALIGN(crypto_aead_blocksize(aead), 4);
	320	esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
	321	esp.plen = esp.clen - skb->len - esp.tfclen;
	322	esp.tailen = esp.tfclen + esp.plen + alen;
	323
f076835a	324	if (!hw_offload \|\| !skb_is_gso(skb)) {
383d0350 SK	325	esp.nfrags = esp6_output_head(x, skb, &esp);
	326	if (esp.nfrags < 0)
	327	return esp.nfrags;
	328	}
	329
3dca3f38 SK	330	seq = xo->seq.low;
3dca3f38 SK	331
0146dca7 SD	332	esp.esph = ip_esp_hdr(skb);
0146dca7 SD	333	esp.esph->spi = x->id.spi;
383d0350 SK	334
	335	skb_push(skb, -skb_network_offset(skb));
	336
	337	if (xo->flags & XFRM_GSO_SEGMENT) {
0146dca7	338	esp.esph->seq_no = htonl(seq);
383d0350	339
3dca3f38 SK	340	if (!skb_is_gso(skb))
	341	xo->seq.low++;
	342	else
	343	xo->seq.low += skb_shinfo(skb)->gso_segs;
383d0350 SK	344	}
383d0350 SK	345
3dca3f38 SK	346	esp.seqno = cpu_to_be64(xo->seq.low + ((u64)xo->seq.hi << 32));
	347
	348	len = skb->len - sizeof(struct ipv6hdr);
	349	if (len > IPV6_MAXPLEN)
	350	len = 0;
	351
	352	ipv6_hdr(skb)->payload_len = htons(len);
	353
c7dbf4c0 SK	354	if (hw_offload) {
	355	if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
	356	return -ENOMEM;
	357
	358	xo = xfrm_offload(skb);
	359	if (!xo)
	360	return -EINVAL;
	361
	362	xo->flags \|= XFRM_XMIT;
383d0350	363	return 0;
c7dbf4c0	364	}
383d0350	365
383d0350	366	err = esp6_output_tail(x, skb, &esp);
4ff0308f	367	if (err)
383d0350 SK	368	return err;
	369
	370	secpath_reset(skb);
	371
	372	return 0;
	373	}
	374
7785bba2 SK	375	static const struct net_offload esp6_offload = {
	376	.callbacks = {
	377	.gro_receive = esp6_gro_receive,
7862b405	378	.gso_segment = esp6_gso_segment,
7785bba2 SK	379	},
	380	};
	381
383d0350	382	static const struct xfrm_type_offload esp6_type_offload = {
383d0350 SK	383	.owner = THIS_MODULE,
	384	.proto = IPPROTO_ESP,
	385	.input_tail = esp6_input_tail,
	386	.xmit = esp6_xmit,
7862b405	387	.encap = esp6_gso_encap,
383d0350 SK	388	};
383d0350 SK	389
7785bba2 SK	390	static int __init esp6_offload_init(void)
7785bba2 SK	391	{
383d0350 SK	392	if (xfrm_register_type_offload(&esp6_type_offload, AF_INET6) < 0) {
	393	pr_info("%s: can't add xfrm type offload\n", __func__);
	394	return -EAGAIN;
	395	}
	396
7785bba2 SK	397	return inet6_add_offload(&esp6_offload, IPPROTO_ESP);
	398	}
	399
	400	static void __exit esp6_offload_exit(void)
	401	{
4f518e80	402	xfrm_unregister_type_offload(&esp6_type_offload, AF_INET6);
7785bba2 SK	403	inet6_del_offload(&esp6_offload, IPPROTO_ESP);
	404	}
	405
	406	module_init(esp6_offload_init);
	407	module_exit(esp6_offload_exit);
	408	MODULE_LICENSE("GPL");
	409	MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
ffdb5211	410	MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET6, XFRM_PROTO_ESP);
67c20de3	411	MODULE_DESCRIPTION("IPV6 GSO/GRO offload support");