Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 834 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
new file mode 100644
index 000000000..ac1a645af
--- /dev/null
+++ b/net/xfrm/xfrm_input.c
@@ -0,0 +1,834 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * xfrm_input.c
+ *
+ * Changes:
+ * 	YOSHIFUJI Hideaki @USAGI
+ * 		Split up af-specific portion
+ *
+ */
+
+#include <linux/bottom_half.h>
+#include <linux/cache.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/percpu.h>
+#include <net/dst.h>
+#include <net/ip.h>
+#include <net/xfrm.h>
+#include <net/ip_tunnels.h>
+#include <net/ip6_tunnel.h>
+#include <net/dst_metadata.h>
+
+#include "xfrm_inout.h"
+
+struct xfrm_trans_tasklet {
+	struct work_struct work;
+	spinlock_t queue_lock;
+	struct sk_buff_head queue;
+};
+
+struct xfrm_trans_cb {
+	union {
+		struct inet_skb_parm	h4;
+#if IS_ENABLED(CONFIG_IPV6)
+		struct inet6_skb_parm	h6;
+#endif
+	} header;
+	int (*finish)(struct net *net, struct sock *sk, struct sk_buff *skb);
+	struct net *net;
+};
+
+#define XFRM_TRANS_SKB_CB(__skb) ((struct xfrm_trans_cb *)&((__skb)->cb[0]))
+
+static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
+static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[2][AF_INET6 + 1];
+
+static struct gro_cells gro_cells;
+static struct net_device xfrm_napi_dev;
+
+static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
+
+int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
+{
+	int err = 0;
+
+	if (WARN_ON(afinfo->family > AF_INET6))
+		return -EAFNOSUPPORT;
+
+	spin_lock_bh(&xfrm_input_afinfo_lock);
+	if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family]))
+		err = -EEXIST;
+	else
+		rcu_assign_pointer(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], afinfo);
+	spin_unlock_bh(&xfrm_input_afinfo_lock);
+	return err;
+}
+EXPORT_SYMBOL(xfrm_input_register_afinfo);
+
+int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
+{
+	int err = 0;
+
+	spin_lock_bh(&xfrm_input_afinfo_lock);
+	if (likely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family])) {
+		if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family] != afinfo))
+			err = -EINVAL;
+		else
+			RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], NULL);
+	}
+	spin_unlock_bh(&xfrm_input_afinfo_lock);
+	synchronize_rcu();
+	return err;
+}
+EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
+
+static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(u8 family, bool is_ipip)
+{
+	const struct xfrm_input_afinfo *afinfo;
+
+	if (WARN_ON_ONCE(family > AF_INET6))
+		return NULL;
+
+	rcu_read_lock();
+	afinfo = rcu_dereference(xfrm_input_afinfo[is_ipip][family]);
+	if (unlikely(!afinfo))
+		rcu_read_unlock();
+	return afinfo;
+}
+
+static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
+		       int err)
+{
+	bool is_ipip = (protocol == IPPROTO_IPIP || protocol == IPPROTO_IPV6);
+	const struct xfrm_input_afinfo *afinfo;
+	int ret;
+
+	afinfo = xfrm_input_get_afinfo(family, is_ipip);
+	if (!afinfo)
+		return -EAFNOSUPPORT;
+
+	ret = afinfo->callback(skb, protocol, err);
+	rcu_read_unlock();
+
+	return ret;
+}
+
+struct sec_path *secpath_set(struct sk_buff *skb)
+{
+	struct sec_path *sp, *tmp = skb_ext_find(skb, SKB_EXT_SEC_PATH);
+
+	sp = skb_ext_add(skb, SKB_EXT_SEC_PATH);
+	if (!sp)
+		return NULL;
+
+	if (tmp) /* reused existing one (was COW'd if needed) */
+		return sp;
+
+	/* allocated new secpath */
+	memset(sp->ovec, 0, sizeof(sp->ovec));
+	sp->olen = 0;
+	sp->len = 0;
+	sp->verified_cnt = 0;
+
+	return sp;
+}
+EXPORT_SYMBOL(secpath_set);
+
+/* Fetch spi and seq from ipsec header */
+
+int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
+{
+	int offset, offset_seq;
+	int hlen;
+
+	switch (nexthdr) {
+	case IPPROTO_AH:
+		hlen = sizeof(struct ip_auth_hdr);
+		offset = offsetof(struct ip_auth_hdr, spi);
+		offset_seq = offsetof(struct ip_auth_hdr, seq_no);
+		break;
+	case IPPROTO_ESP:
+		hlen = sizeof(struct ip_esp_hdr);
+		offset = offsetof(struct ip_esp_hdr, spi);
+		offset_seq = offsetof(struct ip_esp_hdr, seq_no);
+		break;
+	case IPPROTO_COMP:
+		if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
+			return -EINVAL;
+		*spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
+		*seq = 0;
+		return 0;
+	default:
+		return 1;
+	}
+
+	if (!pskb_may_pull(skb, hlen))
+		return -EINVAL;
+
+	*spi = *(__be32 *)(skb_transport_header(skb) + offset);
+	*seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
+	return 0;
+}
+EXPORT_SYMBOL(xfrm_parse_spi);
+
+static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
+{
+	struct iphdr *iph;
+	int optlen = 0;
+	int err = -EINVAL;
+
+	if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
+		struct ip_beet_phdr *ph;
+		int phlen;
+
+		if (!pskb_may_pull(skb, sizeof(*ph)))
+			goto out;
+
+		ph = (struct ip_beet_phdr *)skb->data;
+
+		phlen = sizeof(*ph) + ph->padlen;
+		optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
+		if (optlen < 0 || optlen & 3 || optlen > 250)
+			goto out;
+
+		XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
+
+		if (!pskb_may_pull(skb, phlen))
+			goto out;
+		__skb_pull(skb, phlen);
+	}
+
+	skb_push(skb, sizeof(*iph));
+	skb_reset_network_header(skb);
+	skb_mac_header_rebuild(skb);
+
+	xfrm4_beet_make_header(skb);
+
+	iph = ip_hdr(skb);
+
+	iph->ihl += optlen / 4;
+	iph->tot_len = htons(skb->len);
+	iph->daddr = x->sel.daddr.a4;
+	iph->saddr = x->sel.saddr.a4;
+	iph->check = 0;
+	iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
+	err = 0;
+out:
+	return err;
+}
+
+static void ipip_ecn_decapsulate(struct sk_buff *skb)
+{
+	struct iphdr *inner_iph = ipip_hdr(skb);
+
+	if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
+		IP_ECN_set_ce(inner_iph);
+}
+
+static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
+{
+	int err = -EINVAL;
+
+	if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
+		goto out;
+
+	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+		goto out;
+
+	err = skb_unclone(skb, GFP_ATOMIC);
+	if (err)
+		goto out;
+
+	if (x->props.flags & XFRM_STATE_DECAP_DSCP)
+		ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
+	if (!(x->props.flags & XFRM_STATE_NOECN))
+		ipip_ecn_decapsulate(skb);
+
+	skb_reset_network_header(skb);
+	skb_mac_header_rebuild(skb);
+	if (skb->mac_len)
+		eth_hdr(skb)->h_proto = skb->protocol;
+
+	err = 0;
+
+out:
+	return err;
+}
+
+static void ipip6_ecn_decapsulate(struct sk_buff *skb)
+{
+	struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
+
+	if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
+		IP6_ECN_set_ce(skb, inner_iph);
+}
+
+static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
+{
+	int err = -EINVAL;
+
+	if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
+		goto out;
+	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
+		goto out;
+
+	err = skb_unclone(skb, GFP_ATOMIC);
+	if (err)
+		goto out;
+
+	if (x->props.flags & XFRM_STATE_DECAP_DSCP)
+		ipv6_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipipv6_hdr(skb));
+	if (!(x->props.flags & XFRM_STATE_NOECN))
+		ipip6_ecn_decapsulate(skb);
+
+	skb_reset_network_header(skb);
+	skb_mac_header_rebuild(skb);
+	if (skb->mac_len)
+		eth_hdr(skb)->h_proto = skb->protocol;
+
+	err = 0;
+
+out:
+	return err;
+}
+
+static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
+{
+	struct ipv6hdr *ip6h;
+	int size = sizeof(struct ipv6hdr);
+	int err;
+
+	err = skb_cow_head(skb, size + skb->mac_len);
+	if (err)
+		goto out;
+
+	__skb_push(skb, size);
+	skb_reset_network_header(skb);
+	skb_mac_header_rebuild(skb);
+
+	xfrm6_beet_make_header(skb);
+
+	ip6h = ipv6_hdr(skb);
+	ip6h->payload_len = htons(skb->len - size);
+	ip6h->daddr = x->sel.daddr.in6;
+	ip6h->saddr = x->sel.saddr.in6;
+	err = 0;
+out:
+	return err;
+}
+
+/* Remove encapsulation header.
+ *
+ * The IP header will be moved over the top of the encapsulation
+ * header.
+ *
+ * On entry, the transport header shall point to where the IP header
+ * should be and the network header shall be set to where the IP
+ * header currently is.  skb->data shall point to the start of the
+ * payload.
+ */
+static int
+xfrm_inner_mode_encap_remove(struct xfrm_state *x,
+			     const struct xfrm_mode *inner_mode,
+			     struct sk_buff *skb)
+{
+	switch (inner_mode->encap) {
+	case XFRM_MODE_BEET:
+		if (inner_mode->family == AF_INET)
+			return xfrm4_remove_beet_encap(x, skb);
+		if (inner_mode->family == AF_INET6)
+			return xfrm6_remove_beet_encap(x, skb);
+		break;
+	case XFRM_MODE_TUNNEL:
+		if (inner_mode->family == AF_INET)
+			return xfrm4_remove_tunnel_encap(x, skb);
+		if (inner_mode->family == AF_INET6)
+			return xfrm6_remove_tunnel_encap(x, skb);
+		break;
+	}
+
+	WARN_ON_ONCE(1);
+	return -EOPNOTSUPP;
+}
+
+static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+	const struct xfrm_mode *inner_mode = &x->inner_mode;
+
+	switch (x->outer_mode.family) {
+	case AF_INET:
+		xfrm4_extract_header(skb);
+		break;
+	case AF_INET6:
+		xfrm6_extract_header(skb);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return -EAFNOSUPPORT;
+	}
+
+	if (x->sel.family == AF_UNSPEC) {
+		inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
+		if (!inner_mode)
+			return -EAFNOSUPPORT;
+	}
+
+	switch (inner_mode->family) {
+	case AF_INET:
+		skb->protocol = htons(ETH_P_IP);
+		break;
+	case AF_INET6:
+		skb->protocol = htons(ETH_P_IPV6);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		break;
+	}
+
+	return xfrm_inner_mode_encap_remove(x, inner_mode, skb);
+}
+
+/* Remove encapsulation header.
+ *
+ * The IP header will be moved over the top of the encapsulation header.
+ *
+ * On entry, skb_transport_header() shall point to where the IP header
+ * should be and skb_network_header() shall be set to where the IP header
+ * currently is.  skb->data shall point to the start of the payload.
+ */
+static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+	int ihl = skb->data - skb_transport_header(skb);
+
+	if (skb->transport_header != skb->network_header) {
+		memmove(skb_transport_header(skb),
+			skb_network_header(skb), ihl);
+		skb->network_header = skb->transport_header;
+	}
+	ip_hdr(skb)->tot_len = htons(skb->len + ihl);
+	skb_reset_transport_header(skb);
+	return 0;
+}
+
+static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	int ihl = skb->data - skb_transport_header(skb);
+
+	if (skb->transport_header != skb->network_header) {
+		memmove(skb_transport_header(skb),
+			skb_network_header(skb), ihl);
+		skb->network_header = skb->transport_header;
+	}
+	ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
+					   sizeof(struct ipv6hdr));
+	skb_reset_transport_header(skb);
+	return 0;
+#else
+	WARN_ON_ONCE(1);
+	return -EAFNOSUPPORT;
+#endif
+}
+
+static int xfrm_inner_mode_input(struct xfrm_state *x,
+				 const struct xfrm_mode *inner_mode,
+				 struct sk_buff *skb)
+{
+	switch (inner_mode->encap) {
+	case XFRM_MODE_BEET:
+	case XFRM_MODE_TUNNEL:
+		return xfrm_prepare_input(x, skb);
+	case XFRM_MODE_TRANSPORT:
+		if (inner_mode->family == AF_INET)
+			return xfrm4_transport_input(x, skb);
+		if (inner_mode->family == AF_INET6)
+			return xfrm6_transport_input(x, skb);
+		break;
+	case XFRM_MODE_ROUTEOPTIMIZATION:
+		WARN_ON_ONCE(1);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		break;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
+{
+	const struct xfrm_state_afinfo *afinfo;
+	struct net *net = dev_net(skb->dev);
+	const struct xfrm_mode *inner_mode;
+	int err;
+	__be32 seq;
+	__be32 seq_hi;
+	struct xfrm_state *x = NULL;
+	xfrm_address_t *daddr;
+	u32 mark = skb->mark;
+	unsigned int family = AF_UNSPEC;
+	int decaps = 0;
+	int async = 0;
+	bool xfrm_gro = false;
+	bool crypto_done = false;
+	struct xfrm_offload *xo = xfrm_offload(skb);
+	struct sec_path *sp;
+
+	if (encap_type < 0) {
+		x = xfrm_input_state(skb);
+
+		if (unlikely(x->km.state != XFRM_STATE_VALID)) {
+			if (x->km.state == XFRM_STATE_ACQ)
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
+			else
+				XFRM_INC_STATS(net,
+					       LINUX_MIB_XFRMINSTATEINVALID);
+
+			if (encap_type == -1)
+				dev_put(skb->dev);
+			goto drop;
+		}
+
+		family = x->outer_mode.family;
+
+		/* An encap_type of -1 indicates async resumption. */
+		if (encap_type == -1) {
+			async = 1;
+			seq = XFRM_SKB_CB(skb)->seq.input.low;
+			goto resume;
+		}
+
+		/* encap_type < -1 indicates a GRO call. */
+		encap_type = 0;
+		seq = XFRM_SPI_SKB_CB(skb)->seq;
+
+		if (xo && (xo->flags & CRYPTO_DONE)) {
+			crypto_done = true;
+			family = XFRM_SPI_SKB_CB(skb)->family;
+
+			if (!(xo->status & CRYPTO_SUCCESS)) {
+				if (xo->status &
+				    (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
+				     CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
+				     CRYPTO_TUNNEL_AH_AUTH_FAILED |
+				     CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
+
+					xfrm_audit_state_icvfail(x, skb,
+								 x->type->proto);
+					x->stats.integrity_failed++;
+					XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
+					goto drop;
+				}
+
+				if (xo->status & CRYPTO_INVALID_PROTOCOL) {
+					XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
+					goto drop;
+				}
+
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
+				goto drop;
+			}
+
+			if (xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
+				goto drop;
+			}
+		}
+
+		goto lock;
+	}
+
+	family = XFRM_SPI_SKB_CB(skb)->family;
+
+	/* if tunnel is present override skb->mark value with tunnel i_key */
+	switch (family) {
+	case AF_INET:
+		if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
+			mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
+		break;
+	case AF_INET6:
+		if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
+			mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
+		break;
+	}
+
+	sp = secpath_set(skb);
+	if (!sp) {
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
+		goto drop;
+	}
+
+	seq = 0;
+	if (!spi && xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
+		secpath_reset(skb);
+		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
+		goto drop;
+	}
+
+	daddr = (xfrm_address_t *)(skb_network_header(skb) +
+				   XFRM_SPI_SKB_CB(skb)->daddroff);
+	do {
+		sp = skb_sec_path(skb);
+
+		if (sp->len == XFRM_MAX_DEPTH) {
+			secpath_reset(skb);
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
+			goto drop;
+		}
+
+		x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
+		if (x == NULL) {
+			secpath_reset(skb);
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
+			xfrm_audit_state_notfound(skb, family, spi, seq);
+			goto drop;
+		}
+
+		skb->mark = xfrm_smark_get(skb->mark, x);
+
+		sp->xvec[sp->len++] = x;
+
+		skb_dst_force(skb);
+		if (!skb_dst(skb)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
+			goto drop;
+		}
+
+lock:
+		spin_lock(&x->lock);
+
+		if (unlikely(x->km.state != XFRM_STATE_VALID)) {
+			if (x->km.state == XFRM_STATE_ACQ)
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
+			else
+				XFRM_INC_STATS(net,
+					       LINUX_MIB_XFRMINSTATEINVALID);
+			goto drop_unlock;
+		}
+
+		if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
+			goto drop_unlock;
+		}
+
+		if (xfrm_replay_check(x, skb, seq)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
+			goto drop_unlock;
+		}
+
+		if (xfrm_state_check_expire(x)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
+			goto drop_unlock;
+		}
+
+		spin_unlock(&x->lock);
+
+		if (xfrm_tunnel_check(skb, x, family)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
+			goto drop;
+		}
+
+		seq_hi = htonl(xfrm_replay_seqhi(x, seq));
+
+		XFRM_SKB_CB(skb)->seq.input.low = seq;
+		XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
+
+		dev_hold(skb->dev);
+
+		if (crypto_done)
+			nexthdr = x->type_offload->input_tail(x, skb);
+		else
+			nexthdr = x->type->input(x, skb);
+
+		if (nexthdr == -EINPROGRESS)
+			return 0;
+resume:
+		dev_put(skb->dev);
+
+		spin_lock(&x->lock);
+		if (nexthdr < 0) {
+			if (nexthdr == -EBADMSG) {
+				xfrm_audit_state_icvfail(x, skb,
+							 x->type->proto);
+				x->stats.integrity_failed++;
+			}
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
+			goto drop_unlock;
+		}
+
+		/* only the first xfrm gets the encap type */
+		encap_type = 0;
+
+		if (xfrm_replay_recheck(x, skb, seq)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
+			goto drop_unlock;
+		}
+
+		xfrm_replay_advance(x, seq);
+
+		x->curlft.bytes += skb->len;
+		x->curlft.packets++;
+
+		spin_unlock(&x->lock);
+
+		XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
+
+		inner_mode = &x->inner_mode;
+
+		if (x->sel.family == AF_UNSPEC) {
+			inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
+			if (inner_mode == NULL) {
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
+				goto drop;
+			}
+		}
+
+		if (xfrm_inner_mode_input(x, inner_mode, skb)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
+			goto drop;
+		}
+
+		if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
+			decaps = 1;
+			break;
+		}
+
+		/*
+		 * We need the inner address.  However, we only get here for
+		 * transport mode so the outer address is identical.
+		 */
+		daddr = &x->id.daddr;
+		family = x->outer_mode.family;
+
+		err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
+		if (err < 0) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
+			goto drop;
+		}
+		crypto_done = false;
+	} while (!err);
+
+	err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
+	if (err)
+		goto drop;
+
+	nf_reset_ct(skb);
+
+	if (decaps) {
+		sp = skb_sec_path(skb);
+		if (sp)
+			sp->olen = 0;
+		if (skb_valid_dst(skb))
+			skb_dst_drop(skb);
+		gro_cells_receive(&gro_cells, skb);
+		return 0;
+	} else {
+		xo = xfrm_offload(skb);
+		if (xo)
+			xfrm_gro = xo->flags & XFRM_GRO;
+
+		err = -EAFNOSUPPORT;
+		rcu_read_lock();
+		afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
+		if (likely(afinfo))
+			err = afinfo->transport_finish(skb, xfrm_gro || async);
+		rcu_read_unlock();
+		if (xfrm_gro) {
+			sp = skb_sec_path(skb);
+			if (sp)
+				sp->olen = 0;
+			if (skb_valid_dst(skb))
+				skb_dst_drop(skb);
+			gro_cells_receive(&gro_cells, skb);
+			return err;
+		}
+
+		return err;
+	}
+
+drop_unlock:
+	spin_unlock(&x->lock);
+drop:
+	xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
+	kfree_skb(skb);
+	return 0;
+}
+EXPORT_SYMBOL(xfrm_input);
+
+int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
+{
+	return xfrm_input(skb, nexthdr, 0, -1);
+}
+EXPORT_SYMBOL(xfrm_input_resume);
+
+static void xfrm_trans_reinject(struct work_struct *work)
+{
+	struct xfrm_trans_tasklet *trans = container_of(work, struct xfrm_trans_tasklet, work);
+	struct sk_buff_head queue;
+	struct sk_buff *skb;
+
+	__skb_queue_head_init(&queue);
+	spin_lock_bh(&trans->queue_lock);
+	skb_queue_splice_init(&trans->queue, &queue);
+	spin_unlock_bh(&trans->queue_lock);
+
+	local_bh_disable();
+	while ((skb = __skb_dequeue(&queue)))
+		XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
+					       NULL, skb);
+	local_bh_enable();
+}
+
+int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
+			 int (*finish)(struct net *, struct sock *,
+				       struct sk_buff *))
+{
+	struct xfrm_trans_tasklet *trans;
+
+	trans = this_cpu_ptr(&xfrm_trans_tasklet);
+
+	if (skb_queue_len(&trans->queue) >= READ_ONCE(netdev_max_backlog))
+		return -ENOBUFS;
+
+	BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
+
+	XFRM_TRANS_SKB_CB(skb)->finish = finish;
+	XFRM_TRANS_SKB_CB(skb)->net = net;
+	spin_lock_bh(&trans->queue_lock);
+	__skb_queue_tail(&trans->queue, skb);
+	spin_unlock_bh(&trans->queue_lock);
+	schedule_work(&trans->work);
+	return 0;
+}
+EXPORT_SYMBOL(xfrm_trans_queue_net);
+
+int xfrm_trans_queue(struct sk_buff *skb,
+		     int (*finish)(struct net *, struct sock *,
+				   struct sk_buff *))
+{
+	return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
+}
+EXPORT_SYMBOL(xfrm_trans_queue);
+
+void __init xfrm_input_init(void)
+{
+	int err;
+	int i;
+
+	init_dummy_netdev(&xfrm_napi_dev);
+	err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
+	if (err)
+		gro_cells.cells = NULL;
+
+	for_each_possible_cpu(i) {
+		struct xfrm_trans_tasklet *trans;
+
+		trans = &per_cpu(xfrm_trans_tasklet, i);
+		spin_lock_init(&trans->queue_lock);
+		__skb_queue_head_init(&trans->queue);
+		INIT_WORK(&trans->work, xfrm_trans_reinject);
+	}
+}