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-rw-r--r--net/ipv6/esp6.c972
1 files changed, 972 insertions, 0 deletions
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
new file mode 100644
index 000000000..e3abfc97f
--- /dev/null
+++ b/net/ipv6/esp6.c
@@ -0,0 +1,972 @@
+/*
+ * 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;
+ struct xfrm_offload *xo = xfrm_offload(skb);
+ void *tmp;
+ struct xfrm_state *x;
+
+ if (xo && (xo->flags & XFRM_DEV_RESUME))
+ x = skb->sp->xvec[skb->sp->len - 1];
+ else
+ x = skb_dst(skb)->xfrm;
+
+ tmp = ESP_SKB_CB(skb)->tmp;
+ esp_ssg_unref(x, tmp);
+ kfree(tmp);
+
+ if (xo && (xo->flags & XFRM_DEV_RESUME)) {
+ if (err) {
+ XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
+ kfree_skb(skb);
+ return;
+ }
+
+ skb_push(skb, skb->data - skb_mac_header(skb));
+ secpath_reset(skb);
+ xfrm_dev_resume(skb);
+ } else {
+ 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;
+ int nfrags;
+ struct page *page;
+ struct sk_buff *trailer;
+ int tailen = esp->tailen;
+ unsigned int allocsz;
+
+ allocsz = ALIGN(skb->data_len + tailen, L1_CACHE_BYTES);
+ if (allocsz > ESP_SKB_FRAG_MAXSIZE)
+ goto cow;
+
+ 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);
+
+ tail = page_address(page) + pfrag->offset;
+
+ esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
+
+ 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 && sk_fullsock(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 -ENOSPC:
+ 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;
+ }
+
+ ret = skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2);
+ BUG_ON(ret);
+
+ 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);
+
+ /* 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)) {
+ struct ip_esp_hdr *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;
+
+ err = -ENAMETOOLONG;
+ if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)",
+ x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME)
+ goto error;
+
+ aead = crypto_alloc_aead(aead_name, 0, 0);
+ 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;
+
+ 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;
+ }
+
+ aead = crypto_alloc_aead(authenc_name, 0, 0);
+ 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;
+ default:
+ case XFRM_MODE_TRANSPORT:
+ break;
+ case XFRM_MODE_TUNNEL:
+ x->props.header_len += sizeof(struct ipv6hdr);
+ break;
+ }
+
+ 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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-30 06:41:33 +0000