1 // SPDX-License-Identifier: GPL-2.0-only
2 #define pr_fmt(fmt) "IPsec: " fmt
4 #include <crypto/aead.h>
5 #include <crypto/authenc.h>
7 #include <linux/module.h>
11 #include <linux/scatterlist.h>
12 #include <linux/kernel.h>
13 #include <linux/pfkeyv2.h>
14 #include <linux/rtnetlink.h>
15 #include <linux/slab.h>
16 #include <linux/spinlock.h>
17 #include <linux/in6.h>
19 #include <net/protocol.h>
22 #include <net/espintcp.h>
24 #include <linux/highmem.h>
27 struct xfrm_skb_cb xfrm;
31 struct esp_output_extra {
36 #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0]))
39 * Allocate an AEAD request structure with extra space for SG and IV.
41 * For alignment considerations the IV is placed at the front, followed
42 * by the request and finally the SG list.
44 * TODO: Use spare space in skb for this where possible.
46 static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int extralen)
52 len += crypto_aead_ivsize(aead);
55 len += crypto_aead_alignmask(aead) &
56 ~(crypto_tfm_ctx_alignment() - 1);
57 len = ALIGN(len, crypto_tfm_ctx_alignment());
60 len += sizeof(struct aead_request) + crypto_aead_reqsize(aead);
61 len = ALIGN(len, __alignof__(struct scatterlist));
63 len += sizeof(struct scatterlist) * nfrags;
65 return kmalloc(len, GFP_ATOMIC);
68 static inline void *esp_tmp_extra(void *tmp)
70 return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra));
73 static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int extralen)
75 return crypto_aead_ivsize(aead) ?
76 PTR_ALIGN((u8 *)tmp + extralen,
77 crypto_aead_alignmask(aead) + 1) : tmp + extralen;
80 static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv)
82 struct aead_request *req;
84 req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
85 crypto_tfm_ctx_alignment());
86 aead_request_set_tfm(req, aead);
90 static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead,
91 struct aead_request *req)
93 return (void *)ALIGN((unsigned long)(req + 1) +
94 crypto_aead_reqsize(aead),
95 __alignof__(struct scatterlist));
98 static void esp_ssg_unref(struct xfrm_state *x, void *tmp)
100 struct esp_output_extra *extra = esp_tmp_extra(tmp);
101 struct crypto_aead *aead = x->data;
104 struct aead_request *req;
105 struct scatterlist *sg;
107 if (x->props.flags & XFRM_STATE_ESN)
108 extralen += sizeof(*extra);
110 extra = esp_tmp_extra(tmp);
111 iv = esp_tmp_iv(aead, tmp, extralen);
112 req = esp_tmp_req(aead, iv);
114 /* Unref skb_frag_pages in the src scatterlist if necessary.
115 * Skip the first sg which comes from skb->data.
117 if (req->src != req->dst)
118 for (sg = sg_next(req->src); sg; sg = sg_next(sg))
119 put_page(sg_page(sg));
122 #ifdef CONFIG_INET_ESPINTCP
128 static void esp_free_tcp_sk(struct rcu_head *head)
130 struct esp_tcp_sk *esk = container_of(head, struct esp_tcp_sk, rcu);
136 static struct sock *esp_find_tcp_sk(struct xfrm_state *x)
138 struct xfrm_encap_tmpl *encap = x->encap;
139 struct esp_tcp_sk *esk;
144 sk = rcu_dereference(x->encap_sk);
145 if (sk && sk->sk_state == TCP_ESTABLISHED)
148 spin_lock_bh(&x->lock);
149 sport = encap->encap_sport;
150 dport = encap->encap_dport;
151 nsk = rcu_dereference_protected(x->encap_sk,
152 lockdep_is_held(&x->lock));
153 if (sk && sk == nsk) {
154 esk = kmalloc(sizeof(*esk), GFP_ATOMIC);
156 spin_unlock_bh(&x->lock);
157 return ERR_PTR(-ENOMEM);
159 RCU_INIT_POINTER(x->encap_sk, NULL);
161 call_rcu(&esk->rcu, esp_free_tcp_sk);
163 spin_unlock_bh(&x->lock);
165 sk = inet_lookup_established(xs_net(x), &tcp_hashinfo, x->id.daddr.a4,
166 dport, x->props.saddr.a4, sport, 0);
168 return ERR_PTR(-ENOENT);
170 if (!tcp_is_ulp_esp(sk)) {
172 return ERR_PTR(-EINVAL);
175 spin_lock_bh(&x->lock);
176 nsk = rcu_dereference_protected(x->encap_sk,
177 lockdep_is_held(&x->lock));
178 if (encap->encap_sport != sport ||
179 encap->encap_dport != dport) {
181 sk = nsk ?: ERR_PTR(-EREMCHG);
182 } else if (sk == nsk) {
185 rcu_assign_pointer(x->encap_sk, sk);
187 spin_unlock_bh(&x->lock);
192 static int esp_output_tcp_finish(struct xfrm_state *x, struct sk_buff *skb)
199 sk = esp_find_tcp_sk(x);
200 err = PTR_ERR_OR_ZERO(sk);
205 if (sock_owned_by_user(sk))
206 err = espintcp_queue_out(sk, skb);
208 err = espintcp_push_skb(sk, skb);
216 static int esp_output_tcp_encap_cb(struct net *net, struct sock *sk,
219 struct dst_entry *dst = skb_dst(skb);
220 struct xfrm_state *x = dst->xfrm;
222 return esp_output_tcp_finish(x, skb);
225 static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb)
230 err = xfrm_trans_queue_net(xs_net(x), skb, esp_output_tcp_encap_cb);
233 /* EINPROGRESS just happens to do the right thing. It
234 * actually means that the skb has been consumed and
237 return err ?: -EINPROGRESS;
240 static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb)
248 static void esp_output_done(struct crypto_async_request *base, int err)
250 struct sk_buff *skb = base->data;
251 struct xfrm_offload *xo = xfrm_offload(skb);
253 struct xfrm_state *x;
255 if (xo && (xo->flags & XFRM_DEV_RESUME)) {
256 struct sec_path *sp = skb_sec_path(skb);
258 x = sp->xvec[sp->len - 1];
260 x = skb_dst(skb)->xfrm;
263 tmp = ESP_SKB_CB(skb)->tmp;
264 esp_ssg_unref(x, tmp);
267 if (xo && (xo->flags & XFRM_DEV_RESUME)) {
269 XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
274 skb_push(skb, skb->data - skb_mac_header(skb));
276 xfrm_dev_resume(skb);
279 x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP)
280 esp_output_tail_tcp(x, skb);
282 xfrm_output_resume(skb, err);
286 /* Move ESP header back into place. */
287 static void esp_restore_header(struct sk_buff *skb, unsigned int offset)
289 struct ip_esp_hdr *esph = (void *)(skb->data + offset);
290 void *tmp = ESP_SKB_CB(skb)->tmp;
291 __be32 *seqhi = esp_tmp_extra(tmp);
293 esph->seq_no = esph->spi;
297 static void esp_output_restore_header(struct sk_buff *skb)
299 void *tmp = ESP_SKB_CB(skb)->tmp;
300 struct esp_output_extra *extra = esp_tmp_extra(tmp);
302 esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff -
306 static struct ip_esp_hdr *esp_output_set_extra(struct sk_buff *skb,
307 struct xfrm_state *x,
308 struct ip_esp_hdr *esph,
309 struct esp_output_extra *extra)
311 /* For ESN we move the header forward by 4 bytes to
312 * accomodate the high bits. We will move it back after
315 if ((x->props.flags & XFRM_STATE_ESN)) {
317 struct xfrm_offload *xo = xfrm_offload(skb);
322 seqhi = XFRM_SKB_CB(skb)->seq.output.hi;
324 extra->esphoff = (unsigned char *)esph -
325 skb_transport_header(skb);
326 esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4);
327 extra->seqhi = esph->spi;
328 esph->seq_no = htonl(seqhi);
331 esph->spi = x->id.spi;
336 static void esp_output_done_esn(struct crypto_async_request *base, int err)
338 struct sk_buff *skb = base->data;
340 esp_output_restore_header(skb);
341 esp_output_done(base, err);
344 static struct ip_esp_hdr *esp_output_udp_encap(struct sk_buff *skb,
346 struct esp_info *esp,
354 len = skb->len + esp->tailen - skb_transport_offset(skb);
355 if (len + sizeof(struct iphdr) > IP_MAX_MTU)
356 return ERR_PTR(-EMSGSIZE);
358 uh = (struct udphdr *)esp->esph;
361 uh->len = htons(len);
364 *skb_mac_header(skb) = IPPROTO_UDP;
366 if (encap_type == UDP_ENCAP_ESPINUDP_NON_IKE) {
367 udpdata32 = (__be32 *)(uh + 1);
368 udpdata32[0] = udpdata32[1] = 0;
369 return (struct ip_esp_hdr *)(udpdata32 + 2);
372 return (struct ip_esp_hdr *)(uh + 1);
375 #ifdef CONFIG_INET_ESPINTCP
376 static struct ip_esp_hdr *esp_output_tcp_encap(struct xfrm_state *x,
378 struct esp_info *esp)
380 __be16 *lenp = (void *)esp->esph;
381 struct ip_esp_hdr *esph;
385 len = skb->len + esp->tailen - skb_transport_offset(skb);
386 if (len > IP_MAX_MTU)
387 return ERR_PTR(-EMSGSIZE);
390 sk = esp_find_tcp_sk(x);
397 esph = (struct ip_esp_hdr *)(lenp + 1);
402 static struct ip_esp_hdr *esp_output_tcp_encap(struct xfrm_state *x,
404 struct esp_info *esp)
406 return ERR_PTR(-EOPNOTSUPP);
410 static int esp_output_encap(struct xfrm_state *x, struct sk_buff *skb,
411 struct esp_info *esp)
413 struct xfrm_encap_tmpl *encap = x->encap;
414 struct ip_esp_hdr *esph;
418 spin_lock_bh(&x->lock);
419 sport = encap->encap_sport;
420 dport = encap->encap_dport;
421 encap_type = encap->encap_type;
422 spin_unlock_bh(&x->lock);
424 switch (encap_type) {
426 case UDP_ENCAP_ESPINUDP:
427 case UDP_ENCAP_ESPINUDP_NON_IKE:
428 esph = esp_output_udp_encap(skb, encap_type, esp, sport, dport);
430 case TCP_ENCAP_ESPINTCP:
431 esph = esp_output_tcp_encap(x, skb, esp);
436 return PTR_ERR(esph);
443 int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
449 struct sk_buff *trailer;
450 int tailen = esp->tailen;
452 /* this is non-NULL only with TCP/UDP Encapsulation */
454 int err = esp_output_encap(x, skb, esp);
460 if (!skb_cloned(skb)) {
461 if (tailen <= skb_tailroom(skb)) {
464 tail = skb_tail_pointer(trailer);
467 } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS)
468 && !skb_has_frag_list(skb)) {
470 struct sock *sk = skb->sk;
471 struct page_frag *pfrag = &x->xfrag;
473 esp->inplace = false;
475 allocsize = ALIGN(tailen, L1_CACHE_BYTES);
477 spin_lock_bh(&x->lock);
479 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
480 spin_unlock_bh(&x->lock);
487 tail = page_address(page) + pfrag->offset;
489 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
491 nfrags = skb_shinfo(skb)->nr_frags;
493 __skb_fill_page_desc(skb, nfrags, page, pfrag->offset,
495 skb_shinfo(skb)->nr_frags = ++nfrags;
497 pfrag->offset = pfrag->offset + allocsize;
499 spin_unlock_bh(&x->lock);
504 skb->data_len += tailen;
505 skb->truesize += tailen;
506 if (sk && sk_fullsock(sk))
507 refcount_add(tailen, &sk->sk_wmem_alloc);
514 esph_offset = (unsigned char *)esp->esph - skb_transport_header(skb);
516 nfrags = skb_cow_data(skb, tailen, &trailer);
519 tail = skb_tail_pointer(trailer);
520 esp->esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset);
523 esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
524 pskb_put(skb, trailer, tailen);
529 EXPORT_SYMBOL_GPL(esp_output_head);
531 int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
540 struct ip_esp_hdr *esph;
541 struct crypto_aead *aead;
542 struct aead_request *req;
543 struct scatterlist *sg, *dsg;
544 struct esp_output_extra *extra;
547 assoclen = sizeof(struct ip_esp_hdr);
550 if (x->props.flags & XFRM_STATE_ESN) {
551 extralen += sizeof(*extra);
552 assoclen += sizeof(__be32);
556 alen = crypto_aead_authsize(aead);
557 ivlen = crypto_aead_ivsize(aead);
559 tmp = esp_alloc_tmp(aead, esp->nfrags + 2, extralen);
563 extra = esp_tmp_extra(tmp);
564 iv = esp_tmp_iv(aead, tmp, extralen);
565 req = esp_tmp_req(aead, iv);
566 sg = esp_req_sg(aead, req);
571 dsg = &sg[esp->nfrags];
573 esph = esp_output_set_extra(skb, x, esp->esph, extra);
576 sg_init_table(sg, esp->nfrags);
577 err = skb_to_sgvec(skb, sg,
578 (unsigned char *)esph - skb->data,
579 assoclen + ivlen + esp->clen + alen);
580 if (unlikely(err < 0))
585 struct page_frag *pfrag = &x->xfrag;
587 allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES);
589 spin_lock_bh(&x->lock);
590 if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
591 spin_unlock_bh(&x->lock);
595 skb_shinfo(skb)->nr_frags = 1;
599 /* replace page frags in skb with new page */
600 __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len);
601 pfrag->offset = pfrag->offset + allocsize;
602 spin_unlock_bh(&x->lock);
604 sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1);
605 err = skb_to_sgvec(skb, dsg,
606 (unsigned char *)esph - skb->data,
607 assoclen + ivlen + esp->clen + alen);
608 if (unlikely(err < 0))
612 if ((x->props.flags & XFRM_STATE_ESN))
613 aead_request_set_callback(req, 0, esp_output_done_esn, skb);
615 aead_request_set_callback(req, 0, esp_output_done, skb);
617 aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv);
618 aead_request_set_ad(req, assoclen);
620 memset(iv, 0, ivlen);
621 memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8),
624 ESP_SKB_CB(skb)->tmp = tmp;
625 err = crypto_aead_encrypt(req);
636 if ((x->props.flags & XFRM_STATE_ESN))
637 esp_output_restore_header(skb);
641 esp_ssg_unref(x, tmp);
643 if (!err && x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP)
644 err = esp_output_tail_tcp(x, skb);
651 EXPORT_SYMBOL_GPL(esp_output_tail);
653 static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
657 struct ip_esp_hdr *esph;
658 struct crypto_aead *aead;
663 esp.proto = *skb_mac_header(skb);
664 *skb_mac_header(skb) = IPPROTO_ESP;
666 /* skb is pure payload to encrypt */
669 alen = crypto_aead_authsize(aead);
673 struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb);
676 padto = min(x->tfcpad, xfrm_state_mtu(x, dst->child_mtu_cached));
677 if (skb->len < padto)
678 esp.tfclen = padto - skb->len;
680 blksize = ALIGN(crypto_aead_blocksize(aead), 4);
681 esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
682 esp.plen = esp.clen - skb->len - esp.tfclen;
683 esp.tailen = esp.tfclen + esp.plen + alen;
685 esp.esph = ip_esp_hdr(skb);
687 esp.nfrags = esp_output_head(x, skb, &esp);
692 esph->spi = x->id.spi;
694 esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
695 esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low +
696 ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32));
698 skb_push(skb, -skb_network_offset(skb));
700 return esp_output_tail(x, skb, &esp);
703 static inline int esp_remove_trailer(struct sk_buff *skb)
705 struct xfrm_state *x = xfrm_input_state(skb);
706 struct xfrm_offload *xo = xfrm_offload(skb);
707 struct crypto_aead *aead = x->data;
708 int alen, hlen, elen;
714 alen = crypto_aead_authsize(aead);
715 hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
716 elen = skb->len - hlen;
718 if (xo && (xo->flags & XFRM_ESP_NO_TRAILER)) {
723 if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2))
728 if (padlen + 2 + alen >= elen) {
729 net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n",
730 padlen + 2, elen - alen);
734 trimlen = alen + padlen + 2;
735 if (skb->ip_summed == CHECKSUM_COMPLETE) {
736 csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0);
737 skb->csum = csum_block_sub(skb->csum, csumdiff,
740 pskb_trim(skb, skb->len - trimlen);
748 int esp_input_done2(struct sk_buff *skb, int err)
750 const struct iphdr *iph;
751 struct xfrm_state *x = xfrm_input_state(skb);
752 struct xfrm_offload *xo = xfrm_offload(skb);
753 struct crypto_aead *aead = x->data;
754 int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
757 if (!xo || (xo && !(xo->flags & CRYPTO_DONE)))
758 kfree(ESP_SKB_CB(skb)->tmp);
763 err = esp_remove_trailer(skb);
764 if (unlikely(err < 0))
771 struct xfrm_encap_tmpl *encap = x->encap;
772 struct tcphdr *th = (void *)(skb_network_header(skb) + ihl);
773 struct udphdr *uh = (void *)(skb_network_header(skb) + ihl);
776 switch (x->encap->encap_type) {
777 case TCP_ENCAP_ESPINTCP:
780 case UDP_ENCAP_ESPINUDP:
781 case UDP_ENCAP_ESPINUDP_NON_IKE:
791 * 1) if the NAT-T peer's IP or port changed then
792 * advertize the change to the keying daemon.
793 * This is an inbound SA, so just compare
796 if (iph->saddr != x->props.saddr.a4 ||
797 source != encap->encap_sport) {
798 xfrm_address_t ipaddr;
800 ipaddr.a4 = iph->saddr;
801 km_new_mapping(x, &ipaddr, source);
803 /* XXX: perhaps add an extra
804 * policy check here, to see
805 * if we should allow or
806 * reject a packet from a
813 * 2) ignore UDP/TCP checksums in case
814 * of NAT-T in Transport Mode, or
815 * perform other post-processing fixes
816 * as per draft-ietf-ipsec-udp-encaps-06,
819 if (x->props.mode == XFRM_MODE_TRANSPORT)
820 skb->ip_summed = CHECKSUM_UNNECESSARY;
823 skb_pull_rcsum(skb, hlen);
824 if (x->props.mode == XFRM_MODE_TUNNEL)
825 skb_reset_transport_header(skb);
827 skb_set_transport_header(skb, -ihl);
829 /* RFC4303: Drop dummy packets without any error */
830 if (err == IPPROTO_NONE)
836 EXPORT_SYMBOL_GPL(esp_input_done2);
838 static void esp_input_done(struct crypto_async_request *base, int err)
840 struct sk_buff *skb = base->data;
842 xfrm_input_resume(skb, esp_input_done2(skb, err));
845 static void esp_input_restore_header(struct sk_buff *skb)
847 esp_restore_header(skb, 0);
851 static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi)
853 struct xfrm_state *x = xfrm_input_state(skb);
854 struct ip_esp_hdr *esph;
856 /* For ESN we move the header forward by 4 bytes to
857 * accomodate the high bits. We will move it back after
860 if ((x->props.flags & XFRM_STATE_ESN)) {
861 esph = skb_push(skb, 4);
863 esph->spi = esph->seq_no;
864 esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi;
868 static void esp_input_done_esn(struct crypto_async_request *base, int err)
870 struct sk_buff *skb = base->data;
872 esp_input_restore_header(skb);
873 esp_input_done(base, err);
877 * Note: detecting truncated vs. non-truncated authentication data is very
878 * expensive, so we only support truncated data, which is the recommended
881 static int esp_input(struct xfrm_state *x, struct sk_buff *skb)
883 struct crypto_aead *aead = x->data;
884 struct aead_request *req;
885 struct sk_buff *trailer;
886 int ivlen = crypto_aead_ivsize(aead);
887 int elen = skb->len - sizeof(struct ip_esp_hdr) - ivlen;
894 struct scatterlist *sg;
897 if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + ivlen))
903 assoclen = sizeof(struct ip_esp_hdr);
906 if (x->props.flags & XFRM_STATE_ESN) {
907 seqhilen += sizeof(__be32);
908 assoclen += seqhilen;
911 if (!skb_cloned(skb)) {
912 if (!skb_is_nonlinear(skb)) {
916 } else if (!skb_has_frag_list(skb)) {
917 nfrags = skb_shinfo(skb)->nr_frags;
924 err = skb_cow_data(skb, 0, &trailer);
932 tmp = esp_alloc_tmp(aead, nfrags, seqhilen);
936 ESP_SKB_CB(skb)->tmp = tmp;
937 seqhi = esp_tmp_extra(tmp);
938 iv = esp_tmp_iv(aead, tmp, seqhilen);
939 req = esp_tmp_req(aead, iv);
940 sg = esp_req_sg(aead, req);
942 esp_input_set_header(skb, seqhi);
944 sg_init_table(sg, nfrags);
945 err = skb_to_sgvec(skb, sg, 0, skb->len);
946 if (unlikely(err < 0)) {
951 skb->ip_summed = CHECKSUM_NONE;
953 if ((x->props.flags & XFRM_STATE_ESN))
954 aead_request_set_callback(req, 0, esp_input_done_esn, skb);
956 aead_request_set_callback(req, 0, esp_input_done, skb);
958 aead_request_set_crypt(req, sg, sg, elen + ivlen, iv);
959 aead_request_set_ad(req, assoclen);
961 err = crypto_aead_decrypt(req);
962 if (err == -EINPROGRESS)
965 if ((x->props.flags & XFRM_STATE_ESN))
966 esp_input_restore_header(skb);
968 err = esp_input_done2(skb, err);
974 static int esp4_err(struct sk_buff *skb, u32 info)
976 struct net *net = dev_net(skb->dev);
977 const struct iphdr *iph = (const struct iphdr *)skb->data;
978 struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
979 struct xfrm_state *x;
981 switch (icmp_hdr(skb)->type) {
982 case ICMP_DEST_UNREACH:
983 if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
991 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
992 esph->spi, IPPROTO_ESP, AF_INET);
996 if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
997 ipv4_update_pmtu(skb, net, info, 0, IPPROTO_ESP);
999 ipv4_redirect(skb, net, 0, IPPROTO_ESP);
1005 static void esp_destroy(struct xfrm_state *x)
1007 struct crypto_aead *aead = x->data;
1012 crypto_free_aead(aead);
1015 static int esp_init_aead(struct xfrm_state *x)
1017 char aead_name[CRYPTO_MAX_ALG_NAME];
1018 struct crypto_aead *aead;
1021 err = -ENAMETOOLONG;
1022 if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
1023 x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
1026 aead = crypto_alloc_aead(aead_name, 0, 0);
1027 err = PTR_ERR(aead);
1033 err = crypto_aead_setkey(aead, x->aead->alg_key,
1034 (x->aead->alg_key_len + 7) / 8);
1038 err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8);
1046 static int esp_init_authenc(struct xfrm_state *x)
1048 struct crypto_aead *aead;
1049 struct crypto_authenc_key_param *param;
1053 char authenc_name[CRYPTO_MAX_ALG_NAME];
1054 unsigned int keylen;
1061 err = -ENAMETOOLONG;
1063 if ((x->props.flags & XFRM_STATE_ESN)) {
1064 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
1065 "%s%sauthencesn(%s,%s)%s",
1066 x->geniv ?: "", x->geniv ? "(" : "",
1067 x->aalg ? x->aalg->alg_name : "digest_null",
1069 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
1072 if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
1073 "%s%sauthenc(%s,%s)%s",
1074 x->geniv ?: "", x->geniv ? "(" : "",
1075 x->aalg ? x->aalg->alg_name : "digest_null",
1077 x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME)
1081 aead = crypto_alloc_aead(authenc_name, 0, 0);
1082 err = PTR_ERR(aead);
1088 keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) +
1089 (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param));
1091 key = kmalloc(keylen, GFP_KERNEL);
1097 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
1098 rta->rta_len = RTA_LENGTH(sizeof(*param));
1099 param = RTA_DATA(rta);
1100 p += RTA_SPACE(sizeof(*param));
1103 struct xfrm_algo_desc *aalg_desc;
1105 memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8);
1106 p += (x->aalg->alg_key_len + 7) / 8;
1108 aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0);
1112 if (aalg_desc->uinfo.auth.icv_fullbits / 8 !=
1113 crypto_aead_authsize(aead)) {
1114 pr_info("ESP: %s digestsize %u != %hu\n",
1116 crypto_aead_authsize(aead),
1117 aalg_desc->uinfo.auth.icv_fullbits / 8);
1121 err = crypto_aead_setauthsize(
1122 aead, x->aalg->alg_trunc_len / 8);
1127 param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8);
1128 memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8);
1130 err = crypto_aead_setkey(aead, key, keylen);
1139 static int esp_init_state(struct xfrm_state *x)
1141 struct crypto_aead *aead;
1148 err = esp_init_aead(x);
1150 err = esp_init_authenc(x);
1157 x->props.header_len = sizeof(struct ip_esp_hdr) +
1158 crypto_aead_ivsize(aead);
1159 if (x->props.mode == XFRM_MODE_TUNNEL)
1160 x->props.header_len += sizeof(struct iphdr);
1161 else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6)
1162 x->props.header_len += IPV4_BEET_PHMAXLEN;
1164 struct xfrm_encap_tmpl *encap = x->encap;
1166 switch (encap->encap_type) {
1170 case UDP_ENCAP_ESPINUDP:
1171 x->props.header_len += sizeof(struct udphdr);
1173 case UDP_ENCAP_ESPINUDP_NON_IKE:
1174 x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32);
1176 #ifdef CONFIG_INET_ESPINTCP
1177 case TCP_ENCAP_ESPINTCP:
1178 /* only the length field, TCP encap is done by
1181 x->props.header_len += 2;
1187 align = ALIGN(crypto_aead_blocksize(aead), 4);
1188 x->props.trailer_len = align + 1 + crypto_aead_authsize(aead);
1194 static int esp4_rcv_cb(struct sk_buff *skb, int err)
1199 static const struct xfrm_type esp_type =
1201 .description = "ESP4",
1202 .owner = THIS_MODULE,
1203 .proto = IPPROTO_ESP,
1204 .flags = XFRM_TYPE_REPLAY_PROT,
1205 .init_state = esp_init_state,
1206 .destructor = esp_destroy,
1208 .output = esp_output,
1211 static struct xfrm4_protocol esp4_protocol = {
1212 .handler = xfrm4_rcv,
1213 .input_handler = xfrm_input,
1214 .cb_handler = esp4_rcv_cb,
1215 .err_handler = esp4_err,
1219 static int __init esp4_init(void)
1221 if (xfrm_register_type(&esp_type, AF_INET) < 0) {
1222 pr_info("%s: can't add xfrm type\n", __func__);
1225 if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) {
1226 pr_info("%s: can't add protocol\n", __func__);
1227 xfrm_unregister_type(&esp_type, AF_INET);
1233 static void __exit esp4_fini(void)
1235 if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0)
1236 pr_info("%s: can't remove protocol\n", __func__);
1237 xfrm_unregister_type(&esp_type, AF_INET);
1240 module_init(esp4_init);
1241 module_exit(esp4_fini);
1242 MODULE_LICENSE("GPL");
1243 MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);