1// SPDX-License-Identifier: GPL-2.0
2/*
3 * xfrm_input.c
4 *
5 * Changes:
6 * 	YOSHIFUJI Hideaki @USAGI
7 * 		Split up af-specific portion
8 *
9 */
10
11#include <linux/bottom_half.h>
12#include <linux/cache.h>
13#include <linux/interrupt.h>
14#include <linux/slab.h>
15#include <linux/module.h>
16#include <linux/netdevice.h>
17#include <linux/percpu.h>
18#include <net/dst.h>
19#include <net/ip.h>
20#include <net/xfrm.h>
21#include <net/ip_tunnels.h>
22#include <net/ip6_tunnel.h>
23#include <net/dst_metadata.h>
24#include <net/hotdata.h>
25
26#include "xfrm_inout.h"
27
28struct xfrm_trans_tasklet {
29	struct work_struct work;
30	spinlock_t queue_lock;
31	struct sk_buff_head queue;
32};
33
34struct xfrm_trans_cb {
35	union {
36		struct inet_skb_parm	h4;
37#if IS_ENABLED(CONFIG_IPV6)
38		struct inet6_skb_parm	h6;
39#endif
40	} header;
41	int (*finish)(struct net *net, struct sock *sk, struct sk_buff *skb);
42	struct net *net;
43};
44
45#define XFRM_TRANS_SKB_CB(__skb) ((struct xfrm_trans_cb *)&((__skb)->cb[0]))
46
47static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
48static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[2][AF_INET6 + 1];
49
50static struct gro_cells gro_cells;
51static struct net_device xfrm_napi_dev;
52
53static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
54
55int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
56{
57	int err = 0;
58
59	if (WARN_ON(afinfo->family > AF_INET6))
60		return -EAFNOSUPPORT;
61
62	spin_lock_bh(&xfrm_input_afinfo_lock);
63	if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family]))
64		err = -EEXIST;
65	else
66		rcu_assign_pointer(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], afinfo);
67	spin_unlock_bh(&xfrm_input_afinfo_lock);
68	return err;
69}
70EXPORT_SYMBOL(xfrm_input_register_afinfo);
71
72int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
73{
74	int err = 0;
75
76	spin_lock_bh(&xfrm_input_afinfo_lock);
77	if (likely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family])) {
78		if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family] != afinfo))
79			err = -EINVAL;
80		else
81			RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], NULL);
82	}
83	spin_unlock_bh(&xfrm_input_afinfo_lock);
84	synchronize_rcu();
85	return err;
86}
87EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
88
89static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(u8 family, bool is_ipip)
90{
91	const struct xfrm_input_afinfo *afinfo;
92
93	if (WARN_ON_ONCE(family > AF_INET6))
94		return NULL;
95
96	rcu_read_lock();
97	afinfo = rcu_dereference(xfrm_input_afinfo[is_ipip][family]);
98	if (unlikely(!afinfo))
99		rcu_read_unlock();
100	return afinfo;
101}
102
103static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
104		       int err)
105{
106	bool is_ipip = (protocol == IPPROTO_IPIP || protocol == IPPROTO_IPV6);
107	const struct xfrm_input_afinfo *afinfo;
108	int ret;
109
110	afinfo = xfrm_input_get_afinfo(family, is_ipip);
111	if (!afinfo)
112		return -EAFNOSUPPORT;
113
114	ret = afinfo->callback(skb, protocol, err);
115	rcu_read_unlock();
116
117	return ret;
118}
119
120struct sec_path *secpath_set(struct sk_buff *skb)
121{
122	struct sec_path *sp, *tmp = skb_ext_find(skb, SKB_EXT_SEC_PATH);
123
124	sp = skb_ext_add(skb, SKB_EXT_SEC_PATH);
125	if (!sp)
126		return NULL;
127
128	if (tmp) /* reused existing one (was COW'd if needed) */
129		return sp;
130
131	/* allocated new secpath */
132	memset(sp->ovec, 0, sizeof(sp->ovec));
133	sp->olen = 0;
134	sp->len = 0;
135	sp->verified_cnt = 0;
136
137	return sp;
138}
139EXPORT_SYMBOL(secpath_set);
140
141/* Fetch spi and seq from ipsec header */
142
143int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
144{
145	int offset, offset_seq;
146	int hlen;
147
148	switch (nexthdr) {
149	case IPPROTO_AH:
150		hlen = sizeof(struct ip_auth_hdr);
151		offset = offsetof(struct ip_auth_hdr, spi);
152		offset_seq = offsetof(struct ip_auth_hdr, seq_no);
153		break;
154	case IPPROTO_ESP:
155		hlen = sizeof(struct ip_esp_hdr);
156		offset = offsetof(struct ip_esp_hdr, spi);
157		offset_seq = offsetof(struct ip_esp_hdr, seq_no);
158		break;
159	case IPPROTO_COMP:
160		if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
161			return -EINVAL;
162		*spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
163		*seq = 0;
164		return 0;
165	default:
166		return 1;
167	}
168
169	if (!pskb_may_pull(skb, hlen))
170		return -EINVAL;
171
172	*spi = *(__be32 *)(skb_transport_header(skb) + offset);
173	*seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
174	return 0;
175}
176EXPORT_SYMBOL(xfrm_parse_spi);
177
178static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
179{
180	struct iphdr *iph;
181	int optlen = 0;
182	int err = -EINVAL;
183
184	skb->protocol = htons(ETH_P_IP);
185
186	if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
187		struct ip_beet_phdr *ph;
188		int phlen;
189
190		if (!pskb_may_pull(skb, sizeof(*ph)))
191			goto out;
192
193		ph = (struct ip_beet_phdr *)skb->data;
194
195		phlen = sizeof(*ph) + ph->padlen;
196		optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
197		if (optlen < 0 || optlen & 3 || optlen > 250)
198			goto out;
199
200		XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
201
202		if (!pskb_may_pull(skb, phlen))
203			goto out;
204		__skb_pull(skb, phlen);
205	}
206
207	skb_push(skb, sizeof(*iph));
208	skb_reset_network_header(skb);
209	skb_mac_header_rebuild(skb);
210
211	xfrm4_beet_make_header(skb);
212
213	iph = ip_hdr(skb);
214
215	iph->ihl += optlen / 4;
216	iph->tot_len = htons(skb->len);
217	iph->daddr = x->sel.daddr.a4;
218	iph->saddr = x->sel.saddr.a4;
219	iph->check = 0;
220	iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
221	err = 0;
222out:
223	return err;
224}
225
226static void ipip_ecn_decapsulate(struct sk_buff *skb)
227{
228	struct iphdr *inner_iph = ipip_hdr(skb);
229
230	if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
231		IP_ECN_set_ce(inner_iph);
232}
233
234static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
235{
236	int err = -EINVAL;
237
238	skb->protocol = htons(ETH_P_IP);
239
240	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
241		goto out;
242
243	err = skb_unclone(skb, GFP_ATOMIC);
244	if (err)
245		goto out;
246
247	if (x->props.flags & XFRM_STATE_DECAP_DSCP)
248		ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
249	if (!(x->props.flags & XFRM_STATE_NOECN))
250		ipip_ecn_decapsulate(skb);
251
252	skb_reset_network_header(skb);
253	skb_mac_header_rebuild(skb);
254	if (skb->mac_len)
255		eth_hdr(skb)->h_proto = skb->protocol;
256
257	err = 0;
258
259out:
260	return err;
261}
262
263static void ipip6_ecn_decapsulate(struct sk_buff *skb)
264{
265	struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
266
267	if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
268		IP6_ECN_set_ce(skb, inner_iph);
269}
270
271static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
272{
273	int err = -EINVAL;
274
275	skb->protocol = htons(ETH_P_IPV6);
276
277	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
278		goto out;
279
280	err = skb_unclone(skb, GFP_ATOMIC);
281	if (err)
282		goto out;
283
284	if (x->props.flags & XFRM_STATE_DECAP_DSCP)
285		ipv6_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipipv6_hdr(skb));
286	if (!(x->props.flags & XFRM_STATE_NOECN))
287		ipip6_ecn_decapsulate(skb);
288
289	skb_reset_network_header(skb);
290	skb_mac_header_rebuild(skb);
291	if (skb->mac_len)
292		eth_hdr(skb)->h_proto = skb->protocol;
293
294	err = 0;
295
296out:
297	return err;
298}
299
300static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
301{
302	struct ipv6hdr *ip6h;
303	int size = sizeof(struct ipv6hdr);
304	int err;
305
306	skb->protocol = htons(ETH_P_IPV6);
307
308	err = skb_cow_head(skb, size + skb->mac_len);
309	if (err)
310		goto out;
311
312	__skb_push(skb, size);
313	skb_reset_network_header(skb);
314	skb_mac_header_rebuild(skb);
315
316	xfrm6_beet_make_header(skb);
317
318	ip6h = ipv6_hdr(skb);
319	ip6h->payload_len = htons(skb->len - size);
320	ip6h->daddr = x->sel.daddr.in6;
321	ip6h->saddr = x->sel.saddr.in6;
322	err = 0;
323out:
324	return err;
325}
326
327/* Remove encapsulation header.
328 *
329 * The IP header will be moved over the top of the encapsulation
330 * header.
331 *
332 * On entry, the transport header shall point to where the IP header
333 * should be and the network header shall be set to where the IP
334 * header currently is.  skb->data shall point to the start of the
335 * payload.
336 */
337static int
338xfrm_inner_mode_encap_remove(struct xfrm_state *x,
339			     struct sk_buff *skb)
340{
341	switch (x->props.mode) {
342	case XFRM_MODE_BEET:
343		switch (x->sel.family) {
344		case AF_INET:
345			return xfrm4_remove_beet_encap(x, skb);
346		case AF_INET6:
347			return xfrm6_remove_beet_encap(x, skb);
348		}
349		break;
350	case XFRM_MODE_TUNNEL:
351		switch (XFRM_MODE_SKB_CB(skb)->protocol) {
352		case IPPROTO_IPIP:
353			return xfrm4_remove_tunnel_encap(x, skb);
354		case IPPROTO_IPV6:
355			return xfrm6_remove_tunnel_encap(x, skb);
356		break;
357		}
358		return -EINVAL;
359	}
360
361	WARN_ON_ONCE(1);
362	return -EOPNOTSUPP;
363}
364
365static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
366{
367	switch (x->props.family) {
368	case AF_INET:
369		xfrm4_extract_header(skb);
370		break;
371	case AF_INET6:
372		xfrm6_extract_header(skb);
373		break;
374	default:
375		WARN_ON_ONCE(1);
376		return -EAFNOSUPPORT;
377	}
378
379	return xfrm_inner_mode_encap_remove(x, skb);
380}
381
382/* Remove encapsulation header.
383 *
384 * The IP header will be moved over the top of the encapsulation header.
385 *
386 * On entry, skb_transport_header() shall point to where the IP header
387 * should be and skb_network_header() shall be set to where the IP header
388 * currently is.  skb->data shall point to the start of the payload.
389 */
390static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
391{
392	int ihl = skb->data - skb_transport_header(skb);
393
394	if (skb->transport_header != skb->network_header) {
395		memmove(skb_transport_header(skb),
396			skb_network_header(skb), ihl);
397		skb->network_header = skb->transport_header;
398	}
399	ip_hdr(skb)->tot_len = htons(skb->len + ihl);
400	skb_reset_transport_header(skb);
401	return 0;
402}
403
404static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
405{
406#if IS_ENABLED(CONFIG_IPV6)
407	int ihl = skb->data - skb_transport_header(skb);
408
409	if (skb->transport_header != skb->network_header) {
410		memmove(skb_transport_header(skb),
411			skb_network_header(skb), ihl);
412		skb->network_header = skb->transport_header;
413	}
414	ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
415					   sizeof(struct ipv6hdr));
416	skb_reset_transport_header(skb);
417	return 0;
418#else
419	WARN_ON_ONCE(1);
420	return -EAFNOSUPPORT;
421#endif
422}
423
424static int xfrm_inner_mode_input(struct xfrm_state *x,
425				 struct sk_buff *skb)
426{
427	switch (x->props.mode) {
428	case XFRM_MODE_BEET:
429	case XFRM_MODE_TUNNEL:
430		return xfrm_prepare_input(x, skb);
431	case XFRM_MODE_TRANSPORT:
432		if (x->props.family == AF_INET)
433			return xfrm4_transport_input(x, skb);
434		if (x->props.family == AF_INET6)
435			return xfrm6_transport_input(x, skb);
436		break;
437	case XFRM_MODE_ROUTEOPTIMIZATION:
438		WARN_ON_ONCE(1);
439		break;
440	default:
441		WARN_ON_ONCE(1);
442		break;
443	}
444
445	return -EOPNOTSUPP;
446}
447
448int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
449{
450	const struct xfrm_state_afinfo *afinfo;
451	struct net *net = dev_net(skb->dev);
452	int err;
453	__be32 seq;
454	__be32 seq_hi;
455	struct xfrm_state *x = NULL;
456	xfrm_address_t *daddr;
457	u32 mark = skb->mark;
458	unsigned int family = AF_UNSPEC;
459	int decaps = 0;
460	int async = 0;
461	bool xfrm_gro = false;
462	bool crypto_done = false;
463	struct xfrm_offload *xo = xfrm_offload(skb);
464	struct sec_path *sp;
465
466	if (encap_type < 0 || (xo && xo->flags & XFRM_GRO)) {
467		x = xfrm_input_state(skb);
468
469		if (unlikely(x->km.state != XFRM_STATE_VALID)) {
470			if (x->km.state == XFRM_STATE_ACQ)
471				XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
472			else
473				XFRM_INC_STATS(net,
474					       LINUX_MIB_XFRMINSTATEINVALID);
475
476			if (encap_type == -1)
477				dev_put(skb->dev);
478			goto drop;
479		}
480
481		family = x->props.family;
482
483		/* An encap_type of -1 indicates async resumption. */
484		if (encap_type == -1) {
485			async = 1;
486			seq = XFRM_SKB_CB(skb)->seq.input.low;
487			goto resume;
488		}
489		/* GRO call */
490		seq = XFRM_SPI_SKB_CB(skb)->seq;
491
492		if (xo && (xo->flags & CRYPTO_DONE)) {
493			crypto_done = true;
494			family = XFRM_SPI_SKB_CB(skb)->family;
495
496			if (!(xo->status & CRYPTO_SUCCESS)) {
497				if (xo->status &
498				    (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
499				     CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
500				     CRYPTO_TUNNEL_AH_AUTH_FAILED |
501				     CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
502
503					xfrm_audit_state_icvfail(x, skb,
504								 x->type->proto);
505					x->stats.integrity_failed++;
506					XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
507					goto drop;
508				}
509
510				if (xo->status & CRYPTO_INVALID_PROTOCOL) {
511					XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
512					goto drop;
513				}
514
515				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
516				goto drop;
517			}
518
519			if (xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
520				XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
521				goto drop;
522			}
523		}
524
525		goto lock;
526	}
527
528	family = XFRM_SPI_SKB_CB(skb)->family;
529
530	/* if tunnel is present override skb->mark value with tunnel i_key */
531	switch (family) {
532	case AF_INET:
533		if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
534			mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
535		break;
536	case AF_INET6:
537		if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
538			mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
539		break;
540	}
541
542	sp = secpath_set(skb);
543	if (!sp) {
544		XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
545		goto drop;
546	}
547
548	seq = 0;
549	if (!spi && xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
550		secpath_reset(skb);
551		XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
552		goto drop;
553	}
554
555	daddr = (xfrm_address_t *)(skb_network_header(skb) +
556				   XFRM_SPI_SKB_CB(skb)->daddroff);
557	do {
558		sp = skb_sec_path(skb);
559
560		if (sp->len == XFRM_MAX_DEPTH) {
561			secpath_reset(skb);
562			XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
563			goto drop;
564		}
565
566		x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
567		if (x == NULL) {
568			secpath_reset(skb);
569			XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
570			xfrm_audit_state_notfound(skb, family, spi, seq);
571			goto drop;
572		}
573
574		skb->mark = xfrm_smark_get(skb->mark, x);
575
576		sp->xvec[sp->len++] = x;
577
578		skb_dst_force(skb);
579		if (!skb_dst(skb)) {
580			XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
581			goto drop;
582		}
583
584lock:
585		spin_lock(&x->lock);
586
587		if (unlikely(x->km.state != XFRM_STATE_VALID)) {
588			if (x->km.state == XFRM_STATE_ACQ)
589				XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
590			else
591				XFRM_INC_STATS(net,
592					       LINUX_MIB_XFRMINSTATEINVALID);
593			goto drop_unlock;
594		}
595
596		if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
597			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
598			goto drop_unlock;
599		}
600
601		if (xfrm_replay_check(x, skb, seq)) {
602			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
603			goto drop_unlock;
604		}
605
606		if (xfrm_state_check_expire(x)) {
607			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
608			goto drop_unlock;
609		}
610
611		spin_unlock(&x->lock);
612
613		if (xfrm_tunnel_check(skb, x, family)) {
614			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
615			goto drop;
616		}
617
618		seq_hi = htonl(xfrm_replay_seqhi(x, seq));
619
620		XFRM_SKB_CB(skb)->seq.input.low = seq;
621		XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
622
623		dev_hold(skb->dev);
624
625		if (crypto_done)
626			nexthdr = x->type_offload->input_tail(x, skb);
627		else
628			nexthdr = x->type->input(x, skb);
629
630		if (nexthdr == -EINPROGRESS)
631			return 0;
632resume:
633		dev_put(skb->dev);
634
635		spin_lock(&x->lock);
636		if (nexthdr < 0) {
637			if (nexthdr == -EBADMSG) {
638				xfrm_audit_state_icvfail(x, skb,
639							 x->type->proto);
640				x->stats.integrity_failed++;
641			}
642			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
643			goto drop_unlock;
644		}
645
646		/* only the first xfrm gets the encap type */
647		encap_type = 0;
648
649		if (xfrm_replay_recheck(x, skb, seq)) {
650			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
651			goto drop_unlock;
652		}
653
654		xfrm_replay_advance(x, seq);
655
656		x->curlft.bytes += skb->len;
657		x->curlft.packets++;
658		x->lastused = ktime_get_real_seconds();
659
660		spin_unlock(&x->lock);
661
662		XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
663
664		if (xfrm_inner_mode_input(x, skb)) {
665			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
666			goto drop;
667		}
668
669		if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
670			decaps = 1;
671			break;
672		}
673
674		/*
675		 * We need the inner address.  However, we only get here for
676		 * transport mode so the outer address is identical.
677		 */
678		daddr = &x->id.daddr;
679		family = x->props.family;
680
681		err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
682		if (err < 0) {
683			XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
684			goto drop;
685		}
686		crypto_done = false;
687	} while (!err);
688
689	err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
690	if (err)
691		goto drop;
692
693	nf_reset_ct(skb);
694
695	if (decaps) {
696		sp = skb_sec_path(skb);
697		if (sp)
698			sp->olen = 0;
699		if (skb_valid_dst(skb))
700			skb_dst_drop(skb);
701		gro_cells_receive(&gro_cells, skb);
702		return 0;
703	} else {
704		xo = xfrm_offload(skb);
705		if (xo)
706			xfrm_gro = xo->flags & XFRM_GRO;
707
708		err = -EAFNOSUPPORT;
709		rcu_read_lock();
710		afinfo = xfrm_state_afinfo_get_rcu(x->props.family);
711		if (likely(afinfo))
712			err = afinfo->transport_finish(skb, xfrm_gro || async);
713		rcu_read_unlock();
714		if (xfrm_gro) {
715			sp = skb_sec_path(skb);
716			if (sp)
717				sp->olen = 0;
718			if (skb_valid_dst(skb))
719				skb_dst_drop(skb);
720			gro_cells_receive(&gro_cells, skb);
721			return err;
722		}
723
724		return err;
725	}
726
727drop_unlock:
728	spin_unlock(&x->lock);
729drop:
730	xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
731	kfree_skb(skb);
732	return 0;
733}
734EXPORT_SYMBOL(xfrm_input);
735
736int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
737{
738	return xfrm_input(skb, nexthdr, 0, -1);
739}
740EXPORT_SYMBOL(xfrm_input_resume);
741
742static void xfrm_trans_reinject(struct work_struct *work)
743{
744	struct xfrm_trans_tasklet *trans = container_of(work, struct xfrm_trans_tasklet, work);
745	struct sk_buff_head queue;
746	struct sk_buff *skb;
747
748	__skb_queue_head_init(&queue);
749	spin_lock_bh(&trans->queue_lock);
750	skb_queue_splice_init(&trans->queue, &queue);
751	spin_unlock_bh(&trans->queue_lock);
752
753	local_bh_disable();
754	while ((skb = __skb_dequeue(&queue)))
755		XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
756					       NULL, skb);
757	local_bh_enable();
758}
759
760int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
761			 int (*finish)(struct net *, struct sock *,
762				       struct sk_buff *))
763{
764	struct xfrm_trans_tasklet *trans;
765
766	trans = this_cpu_ptr(&xfrm_trans_tasklet);
767
768	if (skb_queue_len(&trans->queue) >= READ_ONCE(net_hotdata.max_backlog))
769		return -ENOBUFS;
770
771	BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
772
773	XFRM_TRANS_SKB_CB(skb)->finish = finish;
774	XFRM_TRANS_SKB_CB(skb)->net = net;
775	spin_lock_bh(&trans->queue_lock);
776	__skb_queue_tail(&trans->queue, skb);
777	spin_unlock_bh(&trans->queue_lock);
778	schedule_work(&trans->work);
779	return 0;
780}
781EXPORT_SYMBOL(xfrm_trans_queue_net);
782
783int xfrm_trans_queue(struct sk_buff *skb,
784		     int (*finish)(struct net *, struct sock *,
785				   struct sk_buff *))
786{
787	return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
788}
789EXPORT_SYMBOL(xfrm_trans_queue);
790
791void __init xfrm_input_init(void)
792{
793	int err;
794	int i;
795
796	init_dummy_netdev(&xfrm_napi_dev);
797	err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
798	if (err)
799		gro_cells.cells = NULL;
800
801	for_each_possible_cpu(i) {
802		struct xfrm_trans_tasklet *trans;
803
804		trans = &per_cpu(xfrm_trans_tasklet, i);
805		spin_lock_init(&trans->queue_lock);
806		__skb_queue_head_init(&trans->queue);
807		INIT_WORK(&trans->work, xfrm_trans_reinject);
808	}
809}
810