[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;

	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 *)&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)
{
	__be16 type = x->inner_mode.family == AF_INET ? htons(ETH_P_IP)
						      : htons(ETH_P_IPV6);

	return skb_eth_gso_segment(skb, features, type);
}

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;
	}

	if (xo->seq.low < seq)
		xo->seq.hi++;

	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	59
374d1b5a SK	60	if (!pskb_pull(skb, offset))
374d1b5a SK	61	return NULL;
7785bba2	62
e91001ba	63	if (xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq) != 0)
7785bba2 SK	64	goto out;
7785bba2 SK	65
bcd1f8a4 SK	66	xo = xfrm_offload(skb);
bcd1f8a4 SK	67	if (!xo \|\| !(xo->flags & CRYPTO_DONE)) {
0ca64da1 FW	68	struct sec_path *sp = secpath_set(skb);
	69
	70	if (!sp)
bcd1f8a4	71	goto out;
7785bba2	72
0ca64da1	73	if (sp->len == XFRM_MAX_DEPTH)
6ed69184	74	goto out_reset;
7785bba2	75
bcd1f8a4 SK	76	x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
	77	(xfrm_address_t *)&ipv6_hdr(skb)->daddr,
	78	spi, IPPROTO_ESP, AF_INET6);
	79	if (!x)
6ed69184	80	goto out_reset;
7785bba2	81
4e4362d2 UW	82	skb->mark = xfrm_smark_get(skb->mark, x);
4e4362d2 UW	83
0ca64da1 FW	84	sp->xvec[sp->len++] = x;
0ca64da1 FW	85	sp->olen++;
7785bba2	86
bcd1f8a4	87	xo = xfrm_offload(skb);
db87668a	88	if (!xo)
6ed69184	89	goto out_reset;
7785bba2	90	}
bcd1f8a4	91
7785bba2 SK	92	xo->flags \|= XFRM_GRO;
7785bba2 SK	93
ca3a1b85 YK	94	nhoff = esp6_nexthdr_esp_offset(ipv6_hdr(skb), offset);
	95	if (!nhoff)
	96	goto out;
	97
	98	IP6CB(skb)->nhoff = nhoff;
7785bba2 SK	99	XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL;
	100	XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
	101	XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
	102	XFRM_SPI_SKB_CB(skb)->seq = seq;
	103
	104	/* We don't need to handle errors from xfrm_input, it does all
	105	* the error handling and frees the resources on error. */
	106	xfrm_input(skb, IPPROTO_ESP, spi, -2);
	107
	108	return ERR_PTR(-EINPROGRESS);
6ed69184 MJ	109	out_reset:
6ed69184 MJ	110	secpath_reset(skb);
7785bba2 SK	111	out:
	112	skb_push(skb, offset);
	113	NAPI_GRO_CB(skb)->same_flow = 0;
	114	NAPI_GRO_CB(skb)->flush = 1;
	115
	116	return NULL;
	117	}
	118
7862b405 SK	119	static void esp6_gso_encap(struct xfrm_state x, struct sk_buff skb)
	120	{
	121	struct ip_esp_hdr *esph;
	122	struct ipv6hdr *iph = ipv6_hdr(skb);
	123	struct xfrm_offload *xo = xfrm_offload(skb);
3c96ec56	124	u8 proto = iph->nexthdr;
7862b405 SK	125
7862b405 SK	126	skb_push(skb, -skb_network_offset(skb));
3c96ec56 XL	127
	128	if (x->outer_mode.encap == XFRM_MODE_TRANSPORT) {
	129	__be16 frag;
	130
	131	ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &proto, &frag);
	132	}
	133
7862b405 SK	134	esph = ip_esp_hdr(skb);
	135	*skb_mac_header(skb) = IPPROTO_ESP;
	136
	137	esph->spi = x->id.spi;
	138	esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
	139
	140	xo->proto = proto;
	141	}
	142
7613b92b FW	143	static struct sk_buff xfrm6_tunnel_gso_segment(struct xfrm_state x,
	144	struct sk_buff *skb,
	145	netdev_features_t features)
	146	{
26dbd66e SD	147	__be16 type = x->inner_mode.family == AF_INET ? htons(ETH_P_IP)
	148	: htons(ETH_P_IPV6);
	149
	150	return skb_eth_gso_segment(skb, features, type);
7613b92b FW	151	}
	152
	153	static struct sk_buff xfrm6_transport_gso_segment(struct xfrm_state x,
	154	struct sk_buff *skb,
	155	netdev_features_t features)
	156	{
	157	const struct net_offload *ops;
	158	struct sk_buff *segs = ERR_PTR(-EINVAL);
	159	struct xfrm_offload *xo = xfrm_offload(skb);
	160
	161	skb->transport_header += x->props.header_len;
	162	ops = rcu_dereference(inet6_offloads[xo->proto]);
	163	if (likely(ops && ops->callbacks.gso_segment))
	164	segs = ops->callbacks.gso_segment(skb, features);
	165
	166	return segs;
	167	}
	168
7f9e40eb XL	169	static struct sk_buff xfrm6_beet_gso_segment(struct xfrm_state x,
	170	struct sk_buff *skb,
	171	netdev_features_t features)
	172	{
	173	struct xfrm_offload *xo = xfrm_offload(skb);
	174	struct sk_buff *segs = ERR_PTR(-EINVAL);
	175	const struct net_offload *ops;
25a44ae9	176	u8 proto = xo->proto;
7f9e40eb XL	177
	178	skb->transport_header += x->props.header_len;
	179
7f9e40eb XL	180	if (x->sel.family != AF_INET6) {
	181	skb->transport_header -=
	182	(sizeof(struct ipv6hdr) - sizeof(struct iphdr));
	183
56b1b7c6 XL	184	if (proto == IPPROTO_BEETPH) {
	185	struct ip_beet_phdr *ph =
	186	(struct ip_beet_phdr *)skb->data;
	187
	188	skb->transport_header += ph->hdrlen * 8;
	189	proto = ph->nexthdr;
	190	} else {
	191	skb->transport_header -= IPV4_BEET_PHMAXLEN;
	192	}
7f9e40eb	193
7f9e40eb XL	194	if (proto == IPPROTO_TCP)
7f9e40eb XL	195	skb_shinfo(skb)->gso_type \|= SKB_GSO_TCPV6;
56b1b7c6	196	} else {
25a44ae9 XL	197	__be16 frag;
	198
	199	skb->transport_header +=
	200	ipv6_skip_exthdr(skb, 0, &proto, &frag);
7f9e40eb XL	201	}
7f9e40eb XL	202
053c8fdf SK	203	if (proto == IPPROTO_IPIP)
	204	skb_shinfo(skb)->gso_type \|= SKB_GSO_IPXIP6;
	205
7f9e40eb XL	206	__skb_pull(skb, skb_transport_offset(skb));
	207	ops = rcu_dereference(inet6_offloads[proto]);
	208	if (likely(ops && ops->callbacks.gso_segment))
	209	segs = ops->callbacks.gso_segment(skb, features);
	210
	211	return segs;
	212	}
	213
7613b92b FW	214	static struct sk_buff xfrm6_outer_mode_gso_segment(struct xfrm_state x,
	215	struct sk_buff *skb,
	216	netdev_features_t features)
	217	{
c9500d7b	218	switch (x->outer_mode.encap) {
7613b92b FW	219	case XFRM_MODE_TUNNEL:
	220	return xfrm6_tunnel_gso_segment(x, skb, features);
	221	case XFRM_MODE_TRANSPORT:
	222	return xfrm6_transport_gso_segment(x, skb, features);
7f9e40eb XL	223	case XFRM_MODE_BEET:
7f9e40eb XL	224	return xfrm6_beet_gso_segment(x, skb, features);
7613b92b FW	225	}
	226
	227	return ERR_PTR(-EOPNOTSUPP);
	228	}
	229
7862b405 SK	230	static struct sk_buff esp6_gso_segment(struct sk_buff skb,
	231	netdev_features_t features)
	232	{
7862b405 SK	233	struct xfrm_state *x;
	234	struct ip_esp_hdr *esph;
	235	struct crypto_aead *aead;
7862b405 SK	236	netdev_features_t esp_features = features;
7862b405 SK	237	struct xfrm_offload *xo = xfrm_offload(skb);
2294be0f	238	struct sec_path *sp;
7862b405	239
ffa6f571	240	if (!xo)
3dca3f38	241	return ERR_PTR(-EINVAL);
7862b405	242
121d57af	243	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_ESP))
5ca11440	244	return ERR_PTR(-EINVAL);
7862b405	245
2294be0f FW	246	sp = skb_sec_path(skb);
2294be0f FW	247	x = sp->xvec[sp->len - 1];
7862b405 SK	248	aead = x->data;
	249	esph = ip_esp_hdr(skb);
	250
	251	if (esph->spi != x->id.spi)
3dca3f38	252	return ERR_PTR(-EINVAL);
7862b405 SK	253
7862b405 SK	254	if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
3dca3f38	255	return ERR_PTR(-EINVAL);
7862b405 SK	256
	257	__skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
	258
	259	skb->encap_hdr_csum = 1;
	260
fcb662de	261	if (!(features & NETIF_F_HW_ESP) \|\| x->xso.dev != skb->dev)
154deab6 XL	262	esp_features = features & ~(NETIF_F_SG \| NETIF_F_CSUM_MASK \|
154deab6 XL	263	NETIF_F_SCTP_CRC);
5211fcfb	264	else if (!(features & NETIF_F_HW_ESP_TX_CSUM))
154deab6 XL	265	esp_features = features & ~(NETIF_F_CSUM_MASK \|
154deab6 XL	266	NETIF_F_SCTP_CRC);
7862b405	267
3dca3f38	268	xo->flags \|= XFRM_GSO_SEGMENT;
7862b405	269
7613b92b	270	return xfrm6_outer_mode_gso_segment(x, skb, esp_features);
7862b405 SK	271	}
7862b405 SK	272
383d0350 SK	273	static int esp6_input_tail(struct xfrm_state x, struct sk_buff skb)
	274	{
	275	struct crypto_aead *aead = x->data;
e51a6472	276	struct xfrm_offload *xo = xfrm_offload(skb);
383d0350 SK	277
	278	if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
	279	return -EINVAL;
	280
e51a6472 IT	281	if (!(xo->flags & CRYPTO_DONE))
e51a6472 IT	282	skb->ip_summed = CHECKSUM_NONE;
383d0350 SK	283
	284	return esp6_input_done2(skb, 0);
	285	}
	286
	287	static int esp6_xmit(struct xfrm_state x, struct sk_buff skb, netdev_features_t features)
	288	{
3dca3f38	289	int len;
383d0350 SK	290	int err;
	291	int alen;
	292	int blksize;
	293	struct xfrm_offload *xo;
383d0350 SK	294	struct crypto_aead *aead;
	295	struct esp_info esp;
	296	bool hw_offload = true;
3dca3f38	297	__u32 seq;
383d0350 SK	298
	299	esp.inplace = true;
	300
	301	xo = xfrm_offload(skb);
	302
	303	if (!xo)
	304	return -EINVAL;
	305
fcb662de	306	if (!(features & NETIF_F_HW_ESP) \|\| x->xso.dev != skb->dev) {
383d0350	307	xo->flags \|= CRYPTO_FALLBACK;
8f92e03e	308	hw_offload = false;
383d0350 SK	309	}
	310
	311	esp.proto = xo->proto;
	312
	313	/* skb is pure payload to encrypt */
	314
	315	aead = x->data;
	316	alen = crypto_aead_authsize(aead);
	317
	318	esp.tfclen = 0;
	319	/* XXX: Add support for tfc padding here. */
	320
	321	blksize = ALIGN(crypto_aead_blocksize(aead), 4);
	322	esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
	323	esp.plen = esp.clen - skb->len - esp.tfclen;
	324	esp.tailen = esp.tfclen + esp.plen + alen;
	325
f076835a	326	if (!hw_offload \|\| !skb_is_gso(skb)) {
383d0350 SK	327	esp.nfrags = esp6_output_head(x, skb, &esp);
	328	if (esp.nfrags < 0)
	329	return esp.nfrags;
	330	}
	331
3dca3f38 SK	332	seq = xo->seq.low;
3dca3f38 SK	333
0146dca7 SD	334	esp.esph = ip_esp_hdr(skb);
0146dca7 SD	335	esp.esph->spi = x->id.spi;
383d0350 SK	336
	337	skb_push(skb, -skb_network_offset(skb));
	338
	339	if (xo->flags & XFRM_GSO_SEGMENT) {
0146dca7	340	esp.esph->seq_no = htonl(seq);
383d0350	341
3dca3f38 SK	342	if (!skb_is_gso(skb))
	343	xo->seq.low++;
	344	else
	345	xo->seq.low += skb_shinfo(skb)->gso_segs;
383d0350 SK	346	}
383d0350 SK	347
4b549ccc CL	348	if (xo->seq.low < seq)
	349	xo->seq.hi++;
	350
3dca3f38 SK	351	esp.seqno = cpu_to_be64(xo->seq.low + ((u64)xo->seq.hi << 32));
	352
	353	len = skb->len - sizeof(struct ipv6hdr);
	354	if (len > IPV6_MAXPLEN)
	355	len = 0;
	356
	357	ipv6_hdr(skb)->payload_len = htons(len);
	358
c7dbf4c0 SK	359	if (hw_offload) {
	360	if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
	361	return -ENOMEM;
	362
	363	xo = xfrm_offload(skb);
	364	if (!xo)
	365	return -EINVAL;
	366
	367	xo->flags \|= XFRM_XMIT;
383d0350	368	return 0;
c7dbf4c0	369	}
383d0350	370
383d0350	371	err = esp6_output_tail(x, skb, &esp);
4ff0308f	372	if (err)
383d0350 SK	373	return err;
	374
	375	secpath_reset(skb);
	376
	377	return 0;
	378	}
	379
7785bba2 SK	380	static const struct net_offload esp6_offload = {
	381	.callbacks = {
	382	.gro_receive = esp6_gro_receive,
7862b405	383	.gso_segment = esp6_gso_segment,
7785bba2 SK	384	},
	385	};
	386
383d0350	387	static const struct xfrm_type_offload esp6_type_offload = {
383d0350 SK	388	.owner = THIS_MODULE,
	389	.proto = IPPROTO_ESP,
	390	.input_tail = esp6_input_tail,
	391	.xmit = esp6_xmit,
7862b405	392	.encap = esp6_gso_encap,
383d0350 SK	393	};
383d0350 SK	394
7785bba2 SK	395	static int __init esp6_offload_init(void)
7785bba2 SK	396	{
383d0350 SK	397	if (xfrm_register_type_offload(&esp6_type_offload, AF_INET6) < 0) {
	398	pr_info("%s: can't add xfrm type offload\n", __func__);
	399	return -EAGAIN;
	400	}
	401
7785bba2 SK	402	return inet6_add_offload(&esp6_offload, IPPROTO_ESP);
	403	}
	404
	405	static void __exit esp6_offload_exit(void)
	406	{
4f518e80	407	xfrm_unregister_type_offload(&esp6_type_offload, AF_INET6);
7785bba2 SK	408	inet6_del_offload(&esp6_offload, IPPROTO_ESP);
	409	}
	410
	411	module_init(esp6_offload_init);
	412	module_exit(esp6_offload_exit);
	413	MODULE_LICENSE("GPL");
	414	MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
ffdb5211	415	MODULE_ALIAS_XFRM_OFFLOAD_TYPE(AF_INET6, XFRM_PROTO_ESP);
67c20de3	416	MODULE_DESCRIPTION("IPV6 GSO/GRO offload support");