/* * Copyright (C)2002 USAGI/WIDE Project * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see <http://www.gnu.org/licenses/>. * * Authors * * Mitsuru KANDA @USAGI : IPv6 Support * Kazunori MIYAZAWA @USAGI : * Kunihiro Ishiguro <kunihiro@ipinfusion.com> * * This file is derived from net/ipv4/esp.c */ #define pr_fmt(fmt) "IPv6: " fmt #include <crypto/aead.h> #include <crypto/authenc.h> #include <linux/err.h> #include <linux/module.h> #include <net/ip.h> #include <net/xfrm.h> #include <net/esp.h> #include <linux/scatterlist.h> #include <linux/kernel.h> #include <linux/pfkeyv2.h> #include <linux/random.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <net/ip6_route.h> #include <net/icmp.h> #include <net/ipv6.h> #include <net/protocol.h> #include <linux/icmpv6.h> #include <linux/highmem.h> struct esp_skb_cb { struct xfrm_skb_cb xfrm; void *tmp; }; #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) static u32 esp6_get_mtu(struct xfrm_state *x, int mtu); /* * Allocate an AEAD request structure with extra space for SG and IV. * * For alignment considerations the upper 32 bits of the sequence number are * placed at the front, if present. Followed by the IV, the request and finally * the SG list. * * TODO: Use spare space in skb for this where possible. */ static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqihlen) { unsigned int len; len = seqihlen; len += crypto_aead_ivsize(aead); if (len) { len += crypto_aead_alignmask(aead) & ~(crypto_tfm_ctx_alignment() - 1); len = ALIGN(len, crypto_tfm_ctx_alignment()); } len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); len = ALIGN(len, __alignof__(struct scatterlist)); len += sizeof(struct scatterlist) * nfrags; return kmalloc(len, GFP_ATOMIC); } static inline __be32 *esp_tmp_seqhi(void *tmp) { return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); } static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) { return crypto_aead_ivsize(aead) ? PTR_ALIGN((u8 *)tmp + seqhilen, crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; } static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) { struct aead_request *req; req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), crypto_tfm_ctx_alignment()); aead_request_set_tfm(req, aead); return req; } static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, struct aead_request *req) { return (void *)ALIGN((unsigned long)(req + 1) + crypto_aead_reqsize(aead), __alignof__(struct scatterlist)); } static void esp_ssg_unref(struct xfrm_state *x, void *tmp) { struct crypto_aead *aead = x->data; int seqhilen = 0; u8 *iv; struct aead_request *req; struct scatterlist *sg; if (x->props.flags & XFRM_STATE_ESN) seqhilen += sizeof(__be32); iv = esp_tmp_iv(aead, tmp, seqhilen); req = esp_tmp_req(aead, iv); /* Unref skb_frag_pages in the src scatterlist if necessary. * Skip the first sg which comes from skb->data. */ if (req->src != req->dst) for (sg = sg_next(req->src); sg; sg = sg_next(sg)) put_page(sg_page(sg)); } static void esp_output_done(struct crypto_async_request *base, int err) { struct sk_buff *skb = base->data; void *tmp; struct dst_entry *dst = skb_dst(skb); struct xfrm_state *x = dst->xfrm; tmp = ESP_SKB_CB(skb)->tmp; esp_ssg_unref(x, tmp); kfree(tmp); xfrm_output_resume(skb, err); } /* Move ESP header back into place. */ static void esp_restore_header(struct sk_buff *skb, unsigned int offset) { struct ip_esp_hdr *esph = (void *)(skb->data + offset); void *tmp = ESP_SKB_CB(skb)->tmp; __be32 *seqhi = esp_tmp_seqhi(tmp); esph->seq_no = esph->spi; esph->spi = *seqhi; } static void esp_output_restore_header(struct sk_buff *skb) { esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); } static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb, struct xfrm_state *x, struct ip_esp_hdr *esph, __be32 *seqhi) { /* For ESN we move the header forward by 4 bytes to * accomodate the high bits. We will move it back after * encryption. */ if ((x->props.flags & XFRM_STATE_ESN)) { struct xfrm_offload *xo = xfrm_offload(skb); esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); *seqhi = esph->spi; if (xo) esph->seq_no = htonl(xo->seq.hi); else esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); } esph->spi = x->id.spi; return esph; } static void esp_output_done_esn(struct crypto_async_request *base, int err) { struct sk_buff *skb = base->data; esp_output_restore_header(skb); esp_output_done(base, err); } static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto) { /* Fill padding... */ if (tfclen) { memset(tail, 0, tfclen); tail += tfclen; } do { int i; for (i = 0; i < plen - 2; i++) tail[i] = i + 1; } while (0); tail[plen - 2] = plen - 2; tail[plen - 1] = proto; } int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { u8 *tail; u8 *vaddr; int nfrags; struct page *page; struct sk_buff *trailer; int tailen = esp->tailen; if (!skb_cloned(skb)) { if (tailen <= skb_tailroom(skb)) { nfrags = 1; trailer = skb; tail = skb_tail_pointer(trailer); goto skip_cow; } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) && !skb_has_frag_list(skb)) { int allocsize; struct sock *sk = skb->sk; struct page_frag *pfrag = &x->xfrag; esp->inplace = false; allocsize = ALIGN(tailen, L1_CACHE_BYTES); spin_lock_bh(&x->lock); if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { spin_unlock_bh(&x->lock); goto cow; } page = pfrag->page; get_page(page); vaddr = kmap_atomic(page); tail = vaddr + pfrag->offset; esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); kunmap_atomic(vaddr); nfrags = skb_shinfo(skb)->nr_frags; __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, tailen); skb_shinfo(skb)->nr_frags = ++nfrags; pfrag->offset = pfrag->offset + allocsize; spin_unlock_bh(&x->lock); nfrags++; skb->len += tailen; skb->data_len += tailen; skb->truesize += tailen; if (sk) refcount_add(tailen, &sk->sk_wmem_alloc); goto out; } } cow: nfrags = skb_cow_data(skb, tailen, &trailer); if (nfrags < 0) goto out; tail = skb_tail_pointer(trailer); skip_cow: esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); pskb_put(skb, trailer, tailen); out: return nfrags; } EXPORT_SYMBOL_GPL(esp6_output_head); int esp6_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) { u8 *iv; int alen; void *tmp; int ivlen; int assoclen; int seqhilen; __be32 *seqhi; struct page *page; struct ip_esp_hdr *esph; struct aead_request *req; struct crypto_aead *aead; struct scatterlist *sg, *dsg; int err = -ENOMEM; assoclen = sizeof(struct ip_esp_hdr); seqhilen = 0; if (x->props.flags & XFRM_STATE_ESN) { seqhilen += sizeof(__be32); assoclen += sizeof(__be32); } aead = x->data; alen = crypto_aead_authsize(aead); ivlen = crypto_aead_ivsize(aead); tmp = esp_alloc_tmp(aead, esp->nfrags + 2, seqhilen); if (!tmp) goto error; seqhi = esp_tmp_seqhi(tmp); iv = esp_tmp_iv(aead, tmp, seqhilen); req = esp_tmp_req(aead, iv); sg = esp_req_sg(aead, req); if (esp->inplace) dsg = sg; else dsg = &sg[esp->nfrags]; esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi); sg_init_table(sg, esp->nfrags); err = skb_to_sgvec(skb, sg, (unsigned char *)esph - skb->data, assoclen + ivlen + esp->clen + alen); if (unlikely(err < 0)) goto error_free; if (!esp->inplace) { int allocsize; struct page_frag *pfrag = &x->xfrag; allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); spin_lock_bh(&x->lock); if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { spin_unlock_bh(&x->lock); goto error_free; } skb_shinfo(skb)->nr_frags = 1; page = pfrag->page; get_page(page); /* replace page frags in skb with new page */ __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); pfrag->offset = pfrag->offset + allocsize; spin_unlock_bh(&x->lock); sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); err = skb_to_sgvec(skb, dsg, (unsigned char *)esph - skb->data, assoclen + ivlen + esp->clen + alen); if (unlikely(err < 0)) goto error_free; } if ((x->props.flags & XFRM_STATE_ESN)) aead_request_set_callback(req, 0, esp_output_done_esn, skb); else aead_request_set_callback(req, 0, esp_output_done, skb); aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv); aead_request_set_ad(req, assoclen); memset(iv, 0, ivlen); memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8), min(ivlen, 8)); ESP_SKB_CB(skb)->tmp = tmp; err = crypto_aead_encrypt(req); switch (err) { case -EINPROGRESS: goto error; case -EBUSY: err = NET_XMIT_DROP; break; case 0: if ((x->props.flags & XFRM_STATE_ESN)) esp_output_restore_header(skb); } if (sg != dsg) esp_ssg_unref(x, tmp); error_free: kfree(tmp); error: return err; } EXPORT_SYMBOL_GPL(esp6_output_tail); static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) { int alen; int blksize; struct ip_esp_hdr *esph; struct crypto_aead *aead; struct esp_info esp; esp.inplace = true; esp.proto = *skb_mac_header(skb); *skb_mac_header(skb) = IPPROTO_ESP; /* skb is pure payload to encrypt */ aead = x->data; alen = crypto_aead_authsize(aead); esp.tfclen = 0; if (x->tfcpad) { struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); u32 padto; padto = min(x->tfcpad, esp6_get_mtu(x, dst->child_mtu_cached)); if (skb->len < padto) esp.tfclen = padto - skb->len; } 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; esp.nfrags = esp6_output_head(x, skb, &esp); if (esp.nfrags < 0) return esp.nfrags; esph = ip_esp_hdr(skb); esph->spi = x->id.spi; esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); skb_push(skb, -skb_network_offset(skb)); return esp6_output_tail(x, skb, &esp); } static inline int esp_remove_trailer(struct sk_buff *skb) { struct xfrm_state *x = xfrm_input_state(skb); struct xfrm_offload *xo = xfrm_offload(skb); struct crypto_aead *aead = x->data; int alen, hlen, elen; int padlen, trimlen; __wsum csumdiff; u8 nexthdr[2]; int ret; alen = crypto_aead_authsize(aead); hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); elen = skb->len - hlen; if (xo && (xo->flags & XFRM_ESP_NO_TRAILER)) { ret = xo->proto; goto out; } if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2)) BUG(); ret = -EINVAL; padlen = nexthdr[0]; if (padlen + 2 + alen >= elen) { net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", padlen + 2, elen - alen); goto out; } trimlen = alen + padlen + 2; if (skb->ip_summed == CHECKSUM_COMPLETE) { csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0); skb->csum = csum_block_sub(skb->csum, csumdiff, skb->len - trimlen); } pskb_trim(skb, skb->len - trimlen); ret = nexthdr[1]; out: return ret; } int esp6_input_done2(struct sk_buff *skb, int err) { struct xfrm_state *x = xfrm_input_state(skb); struct xfrm_offload *xo = xfrm_offload(skb); struct crypto_aead *aead = x->data; int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); int hdr_len = skb_network_header_len(skb); if (!xo || (xo && !(xo->flags & CRYPTO_DONE))) kfree(ESP_SKB_CB(skb)->tmp); if (unlikely(err)) goto out; err = esp_remove_trailer(skb); if (unlikely(err < 0)) goto out; skb_postpull_rcsum(skb, skb_network_header(skb), skb_network_header_len(skb)); skb_pull_rcsum(skb, hlen); if (x->props.mode == XFRM_MODE_TUNNEL) skb_reset_transport_header(skb); else skb_set_transport_header(skb, -hdr_len); /* RFC4303: Drop dummy packets without any error */ if (err == IPPROTO_NONE) err = -EINVAL; out: return err; } EXPORT_SYMBOL_GPL(esp6_input_done2); static void esp_input_done(struct crypto_async_request *base, int err) { struct sk_buff *skb = base->data; xfrm_input_resume(skb, esp6_input_done2(skb, err)); } static void esp_input_restore_header(struct sk_buff *skb) { esp_restore_header(skb, 0); __skb_pull(skb, 4); } static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) { struct xfrm_state *x = xfrm_input_state(skb); struct ip_esp_hdr *esph = (struct ip_esp_hdr *)skb->data; /* For ESN we move the header forward by 4 bytes to * accomodate the high bits. We will move it back after * decryption. */ if ((x->props.flags & XFRM_STATE_ESN)) { esph = skb_push(skb, 4); *seqhi = esph->spi; esph->spi = esph->seq_no; esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; } } static void esp_input_done_esn(struct crypto_async_request *base, int err) { struct sk_buff *skb = base->data; esp_input_restore_header(skb); esp_input_done(base, err); } static int esp6_input(struct xfrm_state *x, struct sk_buff *skb) { struct ip_esp_hdr *esph; struct crypto_aead *aead = x->data; struct aead_request *req; struct sk_buff *trailer; int ivlen = crypto_aead_ivsize(aead); int elen = skb->len - sizeof(*esph) - ivlen; int nfrags; int assoclen; int seqhilen; int ret = 0; void *tmp; __be32 *seqhi; u8 *iv; struct scatterlist *sg; if (!pskb_may_pull(skb, sizeof(*esph) + ivlen)) { ret = -EINVAL; goto out; } if (elen <= 0) { ret = -EINVAL; goto out; } assoclen = sizeof(*esph); seqhilen = 0; if (x->props.flags & XFRM_STATE_ESN) { seqhilen += sizeof(__be32); assoclen += seqhilen; } if (!skb_cloned(skb)) { if (!skb_is_nonlinear(skb)) { nfrags = 1; goto skip_cow; } else if (!skb_has_frag_list(skb)) { nfrags = skb_shinfo(skb)->nr_frags; nfrags++; goto skip_cow; } } nfrags = skb_cow_data(skb, 0, &trailer); if (nfrags < 0) { ret = -EINVAL; goto out; } skip_cow: ret = -ENOMEM; tmp = esp_alloc_tmp(aead, nfrags, seqhilen); if (!tmp) goto out; ESP_SKB_CB(skb)->tmp = tmp; seqhi = esp_tmp_seqhi(tmp); iv = esp_tmp_iv(aead, tmp, seqhilen); req = esp_tmp_req(aead, iv); sg = esp_req_sg(aead, req); esp_input_set_header(skb, seqhi); sg_init_table(sg, nfrags); ret = skb_to_sgvec(skb, sg, 0, skb->len); if (unlikely(ret < 0)) { kfree(tmp); goto out; } skb->ip_summed = CHECKSUM_NONE; if ((x->props.flags & XFRM_STATE_ESN)) aead_request_set_callback(req, 0, esp_input_done_esn, skb); else aead_request_set_callback(req, 0, esp_input_done, skb); aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); aead_request_set_ad(req, assoclen); ret = crypto_aead_decrypt(req); if (ret == -EINPROGRESS) goto out; if ((x->props.flags & XFRM_STATE_ESN)) esp_input_restore_header(skb); ret = esp6_input_done2(skb, ret); out: return ret; } static u32 esp6_get_mtu(struct xfrm_state *x, int mtu) { struct crypto_aead *aead = x->data; u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); unsigned int net_adj; if (x->props.mode != XFRM_MODE_TUNNEL) net_adj = sizeof(struct ipv6hdr); else net_adj = 0; return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - net_adj) & ~(blksize - 1)) + net_adj - 2; } static int esp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, u8 type, u8 code, int offset, __be32 info) { struct net *net = dev_net(skb->dev); const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data; struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data + offset); struct xfrm_state *x; if (type != ICMPV6_PKT_TOOBIG && type != NDISC_REDIRECT) return 0; x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, esph->spi, IPPROTO_ESP, AF_INET6); if (!x) return 0; if (type == NDISC_REDIRECT) ip6_redirect(skb, net, skb->dev->ifindex, 0, sock_net_uid(net, NULL)); else ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL)); xfrm_state_put(x); return 0; } static void esp6_destroy(struct xfrm_state *x) { struct crypto_aead *aead = x->data; if (!aead) return; crypto_free_aead(aead); } static int esp_init_aead(struct xfrm_state *x) { char aead_name[CRYPTO_MAX_ALG_NAME]; struct crypto_aead *aead; int err; u32 mask = 0; err = -ENAMETOOLONG; if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) goto error; if (x->xso.offload_handle) mask |= CRYPTO_ALG_ASYNC; aead = crypto_alloc_aead(aead_name, 0, mask); err = PTR_ERR(aead); if (IS_ERR(aead)) goto error; x->data = aead; err = crypto_aead_setkey(aead, x->aead->alg_key, (x->aead->alg_key_len + 7) / 8); if (err) goto error; err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); if (err) goto error; error: return err; } static int esp_init_authenc(struct xfrm_state *x) { struct crypto_aead *aead; struct crypto_authenc_key_param *param; struct rtattr *rta; char *key; char *p; char authenc_name[CRYPTO_MAX_ALG_NAME]; unsigned int keylen; int err; u32 mask = 0; err = -EINVAL; if (!x->ealg) goto error; err = -ENAMETOOLONG; if ((x->props.flags & XFRM_STATE_ESN)) { if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, "%s%sauthencesn(%s,%s)%s", x->geniv ?: "", x->geniv ? "(" : "", x->aalg ? x->aalg->alg_name : "digest_null", x->ealg->alg_name, x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) goto error; } else { if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, "%s%sauthenc(%s,%s)%s", x->geniv ?: "", x->geniv ? "(" : "", x->aalg ? x->aalg->alg_name : "digest_null", x->ealg->alg_name, x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) goto error; } if (x->xso.offload_handle) mask |= CRYPTO_ALG_ASYNC; aead = crypto_alloc_aead(authenc_name, 0, mask); err = PTR_ERR(aead); if (IS_ERR(aead)) goto error; x->data = aead; keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); err = -ENOMEM; key = kmalloc(keylen, GFP_KERNEL); if (!key) goto error; p = key; rta = (void *)p; rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; rta->rta_len = RTA_LENGTH(sizeof(*param)); param = RTA_DATA(rta); p += RTA_SPACE(sizeof(*param)); if (x->aalg) { struct xfrm_algo_desc *aalg_desc; memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); p += (x->aalg->alg_key_len + 7) / 8; aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); BUG_ON(!aalg_desc); err = -EINVAL; if (aalg_desc->uinfo.auth.icv_fullbits / 8 != crypto_aead_authsize(aead)) { pr_info("ESP: %s digestsize %u != %hu\n", x->aalg->alg_name, crypto_aead_authsize(aead), aalg_desc->uinfo.auth.icv_fullbits / 8); goto free_key; } err = crypto_aead_setauthsize( aead, x->aalg->alg_trunc_len / 8); if (err) goto free_key; } param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); err = crypto_aead_setkey(aead, key, keylen); free_key: kfree(key); error: return err; } static int esp6_init_state(struct xfrm_state *x) { struct crypto_aead *aead; u32 align; int err; if (x->encap) return -EINVAL; x->data = NULL; if (x->aead) err = esp_init_aead(x); else err = esp_init_authenc(x); if (err) goto error; aead = x->data; x->props.header_len = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); switch (x->props.mode) { case XFRM_MODE_BEET: if (x->sel.family != AF_INET6) x->props.header_len += IPV4_BEET_PHMAXLEN + (sizeof(struct ipv6hdr) - sizeof(struct iphdr)); break; case XFRM_MODE_TRANSPORT: break; case XFRM_MODE_TUNNEL: x->props.header_len += sizeof(struct ipv6hdr); break; default: goto error; } align = ALIGN(crypto_aead_blocksize(aead), 4); x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); error: return err; } static int esp6_rcv_cb(struct sk_buff *skb, int err) { return 0; } static const struct xfrm_type esp6_type = { .description = "ESP6", .owner = THIS_MODULE, .proto = IPPROTO_ESP, .flags = XFRM_TYPE_REPLAY_PROT, .init_state = esp6_init_state, .destructor = esp6_destroy, .get_mtu = esp6_get_mtu, .input = esp6_input, .output = esp6_output, .hdr_offset = xfrm6_find_1stfragopt, }; static struct xfrm6_protocol esp6_protocol = { .handler = xfrm6_rcv, .cb_handler = esp6_rcv_cb, .err_handler = esp6_err, .priority = 0, }; static int __init esp6_init(void) { if (xfrm_register_type(&esp6_type, AF_INET6) < 0) { pr_info("%s: can't add xfrm type\n", __func__); return -EAGAIN; } if (xfrm6_protocol_register(&esp6_protocol, IPPROTO_ESP) < 0) { pr_info("%s: can't add protocol\n", __func__); xfrm_unregister_type(&esp6_type, AF_INET6); return -EAGAIN; } return 0; } static void __exit esp6_fini(void) { if (xfrm6_protocol_deregister(&esp6_protocol, IPPROTO_ESP) < 0) pr_info("%s: can't remove protocol\n", __func__); if (xfrm_unregister_type(&esp6_type, AF_INET6) < 0) pr_info("%s: can't remove xfrm type\n", __func__); } module_init(esp6_init); module_exit(esp6_fini); MODULE_LICENSE("GPL"); MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_ESP);