1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C)2002 USAGI/WIDE Project
7 * Mitsuru KANDA @USAGI : IPv6 Support
8 * Kazunori MIYAZAWA @USAGI :
9 * Kunihiro Ishiguro <kunihiro@ipinfusion.com>
11 * This file is derived from net/ipv4/esp.c
14 #define pr_fmt(fmt) "IPv6: " fmt
16 #include <crypto/aead.h>
17 #include <crypto/authenc.h>
18 #include <linux/err.h>
19 #include <linux/module.h>
23 #include <linux/scatterlist.h>
24 #include <linux/kernel.h>
25 #include <linux/pfkeyv2.h>
26 #include <linux/random.h>
27 #include <linux/slab.h>
28 #include <linux/spinlock.h>
29 #include <net/ip6_checksum.h>
30 #include <net/ip6_route.h>
33 #include <net/protocol.h>
35 #include <linux/icmpv6.h>
37 #include <net/espintcp.h>
38 #include <net/inet6_hashtables.h>
40 #include <linux/highmem.h>
43 struct xfrm_skb_cb xfrm;
47 struct esp_output_extra {
52 #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0]))
55 * Allocate an AEAD request structure with extra space for SG and IV.
57 * For alignment considerations the upper 32 bits of the sequence number are
58 * placed at the front, if present. Followed by the IV, the request and finally
61 * TODO: Use spare space in skb for this where possible.
63 static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqihlen)
69 len += crypto_aead_ivsize(aead);
72 len += crypto_aead_alignmask(aead) &
73 ~(crypto_tfm_ctx_alignment() - 1);
74 len = ALIGN(len, crypto_tfm_ctx_alignment());
77 len += sizeof(struct aead_request) + crypto_aead_reqsize(aead);
78 len = ALIGN(len, __alignof__(struct scatterlist));
80 len += sizeof(struct scatterlist) * nfrags;
82 return kmalloc(len, GFP_ATOMIC);
85 static inline void *esp_tmp_extra(void *tmp)
87 return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra));
90 static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen)
92 return crypto_aead_ivsize(aead) ?
93 PTR_ALIGN((u8 *)tmp + seqhilen,
94 crypto_aead_alignmask(aead) + 1) : tmp + seqhilen;
97 static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv)
99 struct aead_request *req;
101 req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
102 crypto_tfm_ctx_alignment());
103 aead_request_set_tfm(req, aead);
107 static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead,
108 struct aead_request *req)
110 return (void *)ALIGN((unsigned long)(req + 1) +
111 crypto_aead_reqsize(aead),
112 __alignof__(struct scatterlist));
115 static void esp_ssg_unref(struct xfrm_state *x, void *tmp)
117 struct esp_output_extra *extra = esp_tmp_extra(tmp);
118 struct crypto_aead *aead = x->data;
121 struct aead_request *req;
122 struct scatterlist *sg;
124 if (x->props.flags & XFRM_STATE_ESN)
125 extralen += sizeof(*extra);
127 iv = esp_tmp_iv(aead, tmp, extralen);
128 req = esp_tmp_req(aead, iv);
130 /* Unref skb_frag_pages in the src scatterlist if necessary.
131 * Skip the first sg which comes from skb->data.
133 if (req->src != req->dst)
134 for (sg = sg_next(req->src); sg; sg = sg_next(sg))
135 put_page(sg_page(sg));
138 #ifdef CONFIG_INET6_ESPINTCP
144 static void esp_free_tcp_sk(struct rcu_head *head)
146 struct esp_tcp_sk *esk = container_of(head, struct esp_tcp_sk, rcu);
152 static struct sock *esp6_find_tcp_sk(struct xfrm_state *x)
154 struct xfrm_encap_tmpl *encap = x->encap;
155 struct esp_tcp_sk *esk;
160 sk = rcu_dereference(x->encap_sk);
161 if (sk && sk->sk_state == TCP_ESTABLISHED)
164 spin_lock_bh(&x->lock);
165 sport = encap->encap_sport;
166 dport = encap->encap_dport;
167 nsk = rcu_dereference_protected(x->encap_sk,
168 lockdep_is_held(&x->lock));
169 if (sk && sk == nsk) {
170 esk = kmalloc(sizeof(*esk), GFP_ATOMIC);
172 spin_unlock_bh(&x->lock);
173 return ERR_PTR(-ENOMEM);
175 RCU_INIT_POINTER(x->encap_sk, NULL);
177 call_rcu(&esk->rcu, esp_free_tcp_sk);
179 spin_unlock_bh(&x->lock);
181 sk = __inet6_lookup_established(xs_net(x), &tcp_hashinfo, &x->id.daddr.in6,
182 dport, &x->props.saddr.in6, ntohs(sport), 0, 0);
184 return ERR_PTR(-ENOENT);
186 if (!tcp_is_ulp_esp(sk)) {
188 return ERR_PTR(-EINVAL);
191 spin_lock_bh(&x->lock);
192 nsk = rcu_dereference_protected(x->encap_sk,
193 lockdep_is_held(&x->lock));
194 if (encap->encap_sport != sport ||
195 encap->encap_dport != dport) {
197 sk = nsk ?: ERR_PTR(-EREMCHG);
198 } else if (sk == nsk) {
201 rcu_assign_pointer(x->encap_sk, sk);
203 spin_unlock_bh(&x->lock);
208 static int esp_output_tcp_finish(struct xfrm_state *x, struct sk_buff *skb)
215 sk = esp6_find_tcp_sk(x);
216 err = PTR_ERR_OR_ZERO(sk);
221 if (sock_owned_by_user(sk))
222 err = espintcp_queue_out(sk, skb);
224 err = espintcp_push_skb(sk, skb);
232 static int esp_output_tcp_encap_cb(struct net *net, struct sock *sk,
235 struct dst_entry *dst = skb_dst(skb);
236 struct xfrm_state *x = dst->xfrm;
238 return esp_output_tcp_finish(x, skb);
241 static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb)
246 err = xfrm_trans_queue_net(xs_net(x), skb, esp_output_tcp_encap_cb);
249 /* EINPROGRESS just happens to do the right thing. It
250 * actually means that the skb has been consumed and
253 return err ?: -EINPROGRESS;
256 static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb)
264 static void esp_output_encap_csum(struct sk_buff *skb)
266 /* UDP encap with IPv6 requires a valid checksum */
267 if (*skb_mac_header(skb) == IPPROTO_UDP) {
268 struct udphdr *uh = udp_hdr(skb);
269 struct ipv6hdr *ip6h = ipv6_hdr(skb);
270 int len = ntohs(uh->len);
271 unsigned int offset = skb_transport_offset(skb);
272 __wsum csum = skb_checksum(skb, offset, skb->len - offset, 0);
274 uh->check = csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr,
275 len, IPPROTO_UDP, csum);
277 uh->check = CSUM_MANGLED_0;
281 static void esp_output_done(struct crypto_async_request *base, int err)
283 struct sk_buff *skb = base->data;
284 struct xfrm_offload *xo = xfrm_offload(skb);
286 struct xfrm_state *x;
288 if (xo && (xo->flags & XFRM_DEV_RESUME)) {
289 struct sec_path *sp = skb_sec_path(skb);
291 x = sp->xvec[sp->len - 1];
293 x = skb_dst(skb)->xfrm;
296 tmp = ESP_SKB_CB(skb)->tmp;
297 esp_ssg_unref(x, tmp);
300 esp_output_encap_csum(skb);
302 if (xo && (xo->flags & XFRM_DEV_RESUME)) {
304 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
309 skb_push(skb, skb->data - skb_mac_header(skb));
311 xfrm_dev_resume(skb);
314 x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP)
315 esp_output_tail_tcp(x, skb);
317 xfrm_output_resume(skb->sk, skb, err);
321 /* Move ESP header back into place. */
322 static void esp_restore_header(struct sk_buff *skb, unsigned int offset)
324 struct ip_esp_hdr *esph = (void *)(skb->data + offset);
325 void *tmp = ESP_SKB_CB(skb)->tmp;
326 __be32 *seqhi = esp_tmp_extra(tmp);
328 esph->seq_no = esph->spi;
332 static void esp_output_restore_header(struct sk_buff *skb)
334 void *tmp = ESP_SKB_CB(skb)->tmp;
335 struct esp_output_extra *extra = esp_tmp_extra(tmp);
337 esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff -
341 static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb,
342 struct xfrm_state *x,
343 struct ip_esp_hdr *esph,
344 struct esp_output_extra *extra)
346 /* For ESN we move the header forward by 4 bytes to
347 * accomodate the high bits. We will move it back after
350 if ((x->props.flags & XFRM_STATE_ESN)) {
352 struct xfrm_offload *xo = xfrm_offload(skb);
357 seqhi = XFRM_SKB_CB(skb)->seq.output.hi;
359 extra->esphoff = (unsigned char *)esph -
360 skb_transport_header(skb);
361 esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4);
362 extra->seqhi = esph->spi;
363 esph->seq_no = htonl(seqhi);
366 esph->spi = x->id.spi;
371 static void esp_output_done_esn(struct crypto_async_request *base, int err)
373 struct sk_buff *skb = base->data;
375 esp_output_restore_header(skb);
376 esp_output_done(base, err);
379 static struct ip_esp_hdr *esp6_output_udp_encap(struct sk_buff *skb,
381 struct esp_info *esp,
389 len = skb->len + esp->tailen - skb_transport_offset(skb);
391 return ERR_PTR(-EMSGSIZE);
393 uh = (struct udphdr *)esp->esph;
396 uh->len = htons(len);
399 *skb_mac_header(skb) = IPPROTO_UDP;
401 if (encap_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
402 udpdata32 = (__be32 *)(uh + 1);
403 udpdata32[0] = udpdata32[1] = 0;
404 return (struct ip_esp_hdr *)(udpdata32 + 2);
407 return (struct ip_esp_hdr *)(uh + 1);
410 #ifdef CONFIG_INET6_ESPINTCP
411 static struct ip_esp_hdr *esp6_output_tcp_encap(struct xfrm_state *x,
413 struct esp_info *esp)
415 __be16 *lenp = (void *)esp->esph;
416 struct ip_esp_hdr *esph;
420 len = skb->len + esp->tailen - skb_transport_offset(skb);
421 if (len > IP_MAX_MTU)
422 return ERR_PTR(-EMSGSIZE);
425 sk = esp6_find_tcp_sk(x);
432 esph = (struct ip_esp_hdr *)(lenp + 1);
437 static struct ip_esp_hdr *esp6_output_tcp_encap(struct xfrm_state *x,
439 struct esp_info *esp)
441 return ERR_PTR(-EOPNOTSUPP);
445 static int esp6_output_encap(struct xfrm_state *x, struct sk_buff *skb,
446 struct esp_info *esp)
448 struct xfrm_encap_tmpl *encap = x->encap;
449 struct ip_esp_hdr *esph;
453 spin_lock_bh(&x->lock);
454 sport = encap->encap_sport;
455 dport = encap->encap_dport;
456 encap_type = encap->encap_type;
457 spin_unlock_bh(&x->lock);
459 switch (encap_type) {
461 case UDP_ENCAP_ESPINUDP:
462 case UDP_ENCAP_ESPINUDP_NON_IKE:
463 esph = esp6_output_udp_encap(skb, encap_type, esp, sport, dport);
465 case TCP_ENCAP_ESPINTCP:
466 esph = esp6_output_tcp_encap(x, skb, esp);
471 return PTR_ERR(esph);
478 int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
484 struct sk_buff *trailer;
485 int tailen = esp->tailen;
488 int err = esp6_output_encap(x, skb, esp);
494 if (ALIGN(tailen, L1_CACHE_BYTES) > PAGE_SIZE ||
495 ALIGN(skb->data_len, L1_CACHE_BYTES) > PAGE_SIZE)
498 if (!skb_cloned(skb)) {
499 if (tailen <= skb_tailroom(skb)) {
502 tail = skb_tail_pointer(trailer);
505 } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS)
506 && !skb_has_frag_list(skb)) {
508 struct sock *sk = skb->sk;
509 struct page_frag *pfrag = &x->xfrag;
511 esp->inplace = false;
513 allocsize = ALIGN(tailen, L1_CACHE_BYTES);
515 spin_lock_bh(&x->lock);
517 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
518 spin_unlock_bh(&x->lock);
525 tail = page_address(page) + pfrag->offset;
527 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
529 nfrags = skb_shinfo(skb)->nr_frags;
531 __skb_fill_page_desc(skb, nfrags, page, pfrag->offset,
533 skb_shinfo(skb)->nr_frags = ++nfrags;
535 pfrag->offset = pfrag->offset + allocsize;
537 spin_unlock_bh(&x->lock);
542 skb->data_len += tailen;
543 skb->truesize += tailen;
544 if (sk && sk_fullsock(sk))
545 refcount_add(tailen, &sk->sk_wmem_alloc);
552 esph_offset = (unsigned char *)esp->esph - skb_transport_header(skb);
554 nfrags = skb_cow_data(skb, tailen, &trailer);
557 tail = skb_tail_pointer(trailer);
558 esp->esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset);
561 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
562 pskb_put(skb, trailer, tailen);
567 EXPORT_SYMBOL_GPL(esp6_output_head);
569 int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
578 struct ip_esp_hdr *esph;
579 struct aead_request *req;
580 struct crypto_aead *aead;
581 struct scatterlist *sg, *dsg;
582 struct esp_output_extra *extra;
585 assoclen = sizeof(struct ip_esp_hdr);
588 if (x->props.flags & XFRM_STATE_ESN) {
589 extralen += sizeof(*extra);
590 assoclen += sizeof(__be32);
594 alen = crypto_aead_authsize(aead);
595 ivlen = crypto_aead_ivsize(aead);
597 tmp = esp_alloc_tmp(aead, esp->nfrags + 2, extralen);
601 extra = esp_tmp_extra(tmp);
602 iv = esp_tmp_iv(aead, tmp, extralen);
603 req = esp_tmp_req(aead, iv);
604 sg = esp_req_sg(aead, req);
609 dsg = &sg[esp->nfrags];
611 esph = esp_output_set_esn(skb, x, esp->esph, extra);
614 sg_init_table(sg, esp->nfrags);
615 err = skb_to_sgvec(skb, sg,
616 (unsigned char *)esph - skb->data,
617 assoclen + ivlen + esp->clen + alen);
618 if (unlikely(err < 0))
623 struct page_frag *pfrag = &x->xfrag;
625 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES);
627 spin_lock_bh(&x->lock);
628 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
629 spin_unlock_bh(&x->lock);
633 skb_shinfo(skb)->nr_frags = 1;
637 /* replace page frags in skb with new page */
638 __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len);
639 pfrag->offset = pfrag->offset + allocsize;
640 spin_unlock_bh(&x->lock);
642 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1);
643 err = skb_to_sgvec(skb, dsg,
644 (unsigned char *)esph - skb->data,
645 assoclen + ivlen + esp->clen + alen);
646 if (unlikely(err < 0))
650 if ((x->props.flags & XFRM_STATE_ESN))
651 aead_request_set_callback(req, 0, esp_output_done_esn, skb);
653 aead_request_set_callback(req, 0, esp_output_done, skb);
655 aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv);
656 aead_request_set_ad(req, assoclen);
658 memset(iv, 0, ivlen);
659 memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8),
662 ESP_SKB_CB(skb)->tmp = tmp;
663 err = crypto_aead_encrypt(req);
674 if ((x->props.flags & XFRM_STATE_ESN))
675 esp_output_restore_header(skb);
676 esp_output_encap_csum(skb);
680 esp_ssg_unref(x, tmp);
682 if (!err && x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP)
683 err = esp_output_tail_tcp(x, skb);
690 EXPORT_SYMBOL_GPL(esp6_output_tail);
692 static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
696 struct ip_esp_hdr *esph;
697 struct crypto_aead *aead;
702 esp.proto = *skb_mac_header(skb);
703 *skb_mac_header(skb) = IPPROTO_ESP;
705 /* skb is pure payload to encrypt */
708 alen = crypto_aead_authsize(aead);
712 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb);
715 padto = min(x->tfcpad, xfrm_state_mtu(x, dst->child_mtu_cached));
716 if (skb->len < padto)
717 esp.tfclen = padto - skb->len;
719 blksize = ALIGN(crypto_aead_blocksize(aead), 4);
720 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
721 esp.plen = esp.clen - skb->len - esp.tfclen;
722 esp.tailen = esp.tfclen + esp.plen + alen;
724 esp.esph = ip_esp_hdr(skb);
726 esp.nfrags = esp6_output_head(x, skb, &esp);
731 esph->spi = x->id.spi;
733 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
734 esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low +
735 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32));
737 skb_push(skb, -skb_network_offset(skb));
739 return esp6_output_tail(x, skb, &esp);
742 static inline int esp_remove_trailer(struct sk_buff *skb)
744 struct xfrm_state *x = xfrm_input_state(skb);
745 struct xfrm_offload *xo = xfrm_offload(skb);
746 struct crypto_aead *aead = x->data;
747 int alen, hlen, elen;
753 alen = crypto_aead_authsize(aead);
754 hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
755 elen = skb->len - hlen;
757 if (xo && (xo->flags & XFRM_ESP_NO_TRAILER)) {
762 ret = skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2);
767 if (padlen + 2 + alen >= elen) {
768 net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n",
769 padlen + 2, elen - alen);
773 trimlen = alen + padlen + 2;
774 if (skb->ip_summed == CHECKSUM_COMPLETE) {
775 csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0);
776 skb->csum = csum_block_sub(skb->csum, csumdiff,
779 ret = pskb_trim(skb, skb->len - trimlen);
789 int esp6_input_done2(struct sk_buff *skb, int err)
791 struct xfrm_state *x = xfrm_input_state(skb);
792 struct xfrm_offload *xo = xfrm_offload(skb);
793 struct crypto_aead *aead = x->data;
794 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
795 int hdr_len = skb_network_header_len(skb);
797 if (!xo || (xo && !(xo->flags & CRYPTO_DONE)))
798 kfree(ESP_SKB_CB(skb)->tmp);
803 err = esp_remove_trailer(skb);
804 if (unlikely(err < 0))
808 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
809 int offset = skb_network_offset(skb) + sizeof(*ip6h);
810 struct xfrm_encap_tmpl *encap = x->encap;
811 u8 nexthdr = ip6h->nexthdr;
812 __be16 frag_off, source;
816 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
822 uh = (void *)(skb->data + offset);
823 th = (void *)(skb->data + offset);
826 switch (x->encap->encap_type) {
827 case TCP_ENCAP_ESPINTCP:
830 case UDP_ENCAP_ESPINUDP:
831 case UDP_ENCAP_ESPINUDP_NON_IKE:
841 * 1) if the NAT-T peer's IP or port changed then
842 * advertize the change to the keying daemon.
843 * This is an inbound SA, so just compare
846 if (!ipv6_addr_equal(&ip6h->saddr, &x->props.saddr.in6) ||
847 source != encap->encap_sport) {
848 xfrm_address_t ipaddr;
850 memcpy(&ipaddr.a6, &ip6h->saddr.s6_addr, sizeof(ipaddr.a6));
851 km_new_mapping(x, &ipaddr, source);
853 /* XXX: perhaps add an extra
854 * policy check here, to see
855 * if we should allow or
856 * reject a packet from a
863 * 2) ignore UDP/TCP checksums in case
864 * of NAT-T in Transport Mode, or
865 * perform other post-processing fixes
866 * as per draft-ietf-ipsec-udp-encaps-06,
869 if (x->props.mode == XFRM_MODE_TRANSPORT)
870 skb->ip_summed = CHECKSUM_UNNECESSARY;
873 skb_postpull_rcsum(skb, skb_network_header(skb),
874 skb_network_header_len(skb));
875 skb_pull_rcsum(skb, hlen);
876 if (x->props.mode == XFRM_MODE_TUNNEL)
877 skb_reset_transport_header(skb);
879 skb_set_transport_header(skb, -hdr_len);
881 /* RFC4303: Drop dummy packets without any error */
882 if (err == IPPROTO_NONE)
888 EXPORT_SYMBOL_GPL(esp6_input_done2);
890 static void esp_input_done(struct crypto_async_request *base, int err)
892 struct sk_buff *skb = base->data;
894 xfrm_input_resume(skb, esp6_input_done2(skb, err));
897 static void esp_input_restore_header(struct sk_buff *skb)
899 esp_restore_header(skb, 0);
903 static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi)
905 struct xfrm_state *x = xfrm_input_state(skb);
907 /* For ESN we move the header forward by 4 bytes to
908 * accomodate the high bits. We will move it back after
911 if ((x->props.flags & XFRM_STATE_ESN)) {
912 struct ip_esp_hdr *esph = skb_push(skb, 4);
915 esph->spi = esph->seq_no;
916 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi;
920 static void esp_input_done_esn(struct crypto_async_request *base, int err)
922 struct sk_buff *skb = base->data;
924 esp_input_restore_header(skb);
925 esp_input_done(base, err);
928 static int esp6_input(struct xfrm_state *x, struct sk_buff *skb)
930 struct crypto_aead *aead = x->data;
931 struct aead_request *req;
932 struct sk_buff *trailer;
933 int ivlen = crypto_aead_ivsize(aead);
934 int elen = skb->len - sizeof(struct ip_esp_hdr) - ivlen;
942 struct scatterlist *sg;
944 if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + ivlen)) {
954 assoclen = sizeof(struct ip_esp_hdr);
957 if (x->props.flags & XFRM_STATE_ESN) {
958 seqhilen += sizeof(__be32);
959 assoclen += seqhilen;
962 if (!skb_cloned(skb)) {
963 if (!skb_is_nonlinear(skb)) {
967 } else if (!skb_has_frag_list(skb)) {
968 nfrags = skb_shinfo(skb)->nr_frags;
975 nfrags = skb_cow_data(skb, 0, &trailer);
983 tmp = esp_alloc_tmp(aead, nfrags, seqhilen);
987 ESP_SKB_CB(skb)->tmp = tmp;
988 seqhi = esp_tmp_extra(tmp);
989 iv = esp_tmp_iv(aead, tmp, seqhilen);
990 req = esp_tmp_req(aead, iv);
991 sg = esp_req_sg(aead, req);
993 esp_input_set_header(skb, seqhi);
995 sg_init_table(sg, nfrags);
996 ret = skb_to_sgvec(skb, sg, 0, skb->len);
997 if (unlikely(ret < 0)) {
1002 skb->ip_summed = CHECKSUM_NONE;
1004 if ((x->props.flags & XFRM_STATE_ESN))
1005 aead_request_set_callback(req, 0, esp_input_done_esn, skb);
1007 aead_request_set_callback(req, 0, esp_input_done, skb);
1009 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv);
1010 aead_request_set_ad(req, assoclen);
1012 ret = crypto_aead_decrypt(req);
1013 if (ret == -EINPROGRESS)
1016 if ((x->props.flags & XFRM_STATE_ESN))
1017 esp_input_restore_header(skb);
1019 ret = esp6_input_done2(skb, ret);
1025 static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
1026 u8 type, u8 code, int offset, __be32 info)
1028 struct net *net = dev_net(skb->dev);
1029 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
1030 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset);
1031 struct xfrm_state *x;
1033 if (type != ICMPV6_PKT_TOOBIG &&
1034 type != NDISC_REDIRECT)
1037 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
1038 esph->spi, IPPROTO_ESP, AF_INET6);
1042 if (type == NDISC_REDIRECT)
1043 ip6_redirect(skb, net, skb->dev->ifindex, 0,
1044 sock_net_uid(net, NULL));
1046 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
1052 static void esp6_destroy(struct xfrm_state *x)
1054 struct crypto_aead *aead = x->data;
1059 crypto_free_aead(aead);
1062 static int esp_init_aead(struct xfrm_state *x)
1064 char aead_name[CRYPTO_MAX_ALG_NAME];
1065 struct crypto_aead *aead;
1068 err = -ENAMETOOLONG;
1069 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
1070 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
1073 aead = crypto_alloc_aead(aead_name, 0, 0);
1074 err = PTR_ERR(aead);
1080 err = crypto_aead_setkey(aead, x->aead->alg_key,
1081 (x->aead->alg_key_len + 7) / 8);
1085 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8);
1093 static int esp_init_authenc(struct xfrm_state *x)
1095 struct crypto_aead *aead;
1096 struct crypto_authenc_key_param *param;
1100 char authenc_name[CRYPTO_MAX_ALG_NAME];
1101 unsigned int keylen;
1108 err = -ENAMETOOLONG;
1110 if ((x->props.flags & XFRM_STATE_ESN)) {
1111 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
1112 "%s%sauthencesn(%s,%s)%s",
1113 x->geniv ?: "", x->geniv ? "(" : "",
1114 x->aalg ? x->aalg->alg_name : "digest_null",
1116 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
1119 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
1120 "%s%sauthenc(%s,%s)%s",
1121 x->geniv ?: "", x->geniv ? "(" : "",
1122 x->aalg ? x->aalg->alg_name : "digest_null",
1124 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
1128 aead = crypto_alloc_aead(authenc_name, 0, 0);
1129 err = PTR_ERR(aead);
1135 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) +
1136 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param));
1138 key = kmalloc(keylen, GFP_KERNEL);
1144 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
1145 rta->rta_len = RTA_LENGTH(sizeof(*param));
1146 param = RTA_DATA(rta);
1147 p += RTA_SPACE(sizeof(*param));
1150 struct xfrm_algo_desc *aalg_desc;
1152 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8);
1153 p += (x->aalg->alg_key_len + 7) / 8;
1155 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
1159 if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
1160 crypto_aead_authsize(aead)) {
1161 pr_info("ESP: %s digestsize %u != %hu\n",
1163 crypto_aead_authsize(aead),
1164 aalg_desc->uinfo.auth.icv_fullbits / 8);
1168 err = crypto_aead_setauthsize(
1169 aead, x->aalg->alg_trunc_len / 8);
1174 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
1175 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
1177 err = crypto_aead_setkey(aead, key, keylen);
1186 static int esp6_init_state(struct xfrm_state *x)
1188 struct crypto_aead *aead;
1195 err = esp_init_aead(x);
1197 err = esp_init_authenc(x);
1204 x->props.header_len = sizeof(struct ip_esp_hdr) +
1205 crypto_aead_ivsize(aead);
1206 switch (x->props.mode) {
1207 case XFRM_MODE_BEET:
1208 if (x->sel.family != AF_INET6)
1209 x->props.header_len += IPV4_BEET_PHMAXLEN +
1210 (sizeof(struct ipv6hdr) - sizeof(struct iphdr));
1213 case XFRM_MODE_TRANSPORT:
1215 case XFRM_MODE_TUNNEL:
1216 x->props.header_len += sizeof(struct ipv6hdr);
1221 struct xfrm_encap_tmpl *encap = x->encap;
1223 switch (encap->encap_type) {
1227 case UDP_ENCAP_ESPINUDP:
1228 x->props.header_len += sizeof(struct udphdr);
1230 case UDP_ENCAP_ESPINUDP_NON_IKE:
1231 x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32);
1233 #ifdef CONFIG_INET6_ESPINTCP
1234 case TCP_ENCAP_ESPINTCP:
1235 /* only the length field, TCP encap is done by
1238 x->props.header_len += 2;
1244 align = ALIGN(crypto_aead_blocksize(aead), 4);
1245 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead);
1251 static int esp6_rcv_cb(struct sk_buff *skb, int err)
1256 static const struct xfrm_type esp6_type = {
1257 .description = "ESP6",
1258 .owner = THIS_MODULE,
1259 .proto = IPPROTO_ESP,
1260 .flags = XFRM_TYPE_REPLAY_PROT,
1261 .init_state = esp6_init_state,
1262 .destructor = esp6_destroy,
1263 .input = esp6_input,
1264 .output = esp6_output,
1265 .hdr_offset = xfrm6_find_1stfragopt,
1268 static struct xfrm6_protocol esp6_protocol = {
1269 .handler = xfrm6_rcv,
1270 .input_handler = xfrm_input,
1271 .cb_handler = esp6_rcv_cb,
1272 .err_handler = esp6_err,
1276 static int __init esp6_init(void)
1278 if (xfrm_register_type(&esp6_type, AF_INET6) < 0) {
1279 pr_info("%s: can't add xfrm type\n", __func__);
1282 if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) {
1283 pr_info("%s: can't add protocol\n", __func__);
1284 xfrm_unregister_type(&esp6_type, AF_INET6);
1291 static void __exit esp6_fini(void)
1293 if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0)
1294 pr_info("%s: can't remove protocol\n", __func__);
1295 xfrm_unregister_type(&esp6_type, AF_INET6);
1298 module_init(esp6_init);
1299 module_exit(esp6_fini);
1301 MODULE_LICENSE("GPL");
1302 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP);