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-rw-r--r--kernel/net/ipv4/esp4.c731
1 files changed, 731 insertions, 0 deletions
diff --git a/kernel/net/ipv4/esp4.c b/kernel/net/ipv4/esp4.c
new file mode 100644
index 000000000..30b544f02
--- /dev/null
+++ b/kernel/net/ipv4/esp4.c
@@ -0,0 +1,731 @@
+#define pr_fmt(fmt) "IPsec: " 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/rtnetlink.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/in6.h>
+#include <net/icmp.h>
+#include <net/protocol.h>
+#include <net/udp.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 esp4_get_mtu(struct xfrm_state *x, int mtu);
+
+/*
+ * Allocate an AEAD request structure with extra space for SG and IV.
+ *
+ * For alignment considerations the IV is placed at the front, followed
+ * by 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 seqhilen)
+{
+ unsigned int len;
+
+ len = seqhilen;
+
+ 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_givcrypt_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_givcrypt_request *esp_tmp_givreq(
+ struct crypto_aead *aead, u8 *iv)
+{
+ struct aead_givcrypt_request *req;
+
+ req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
+ crypto_tfm_ctx_alignment());
+ aead_givcrypt_set_tfm(req, aead);
+ return req;
+}
+
+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 inline struct scatterlist *esp_givreq_sg(
+ struct crypto_aead *aead, struct aead_givcrypt_request *req)
+{
+ return (void *)ALIGN((unsigned long)(req + 1) +
+ crypto_aead_reqsize(aead),
+ __alignof__(struct scatterlist));
+}
+
+static void esp_output_done(struct crypto_async_request *base, int err)
+{
+ struct sk_buff *skb = base->data;
+
+ kfree(ESP_SKB_CB(skb)->tmp);
+ xfrm_output_resume(skb, err);
+}
+
+static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
+{
+ int err;
+ struct ip_esp_hdr *esph;
+ struct crypto_aead *aead;
+ struct aead_givcrypt_request *req;
+ struct scatterlist *sg;
+ struct scatterlist *asg;
+ struct sk_buff *trailer;
+ void *tmp;
+ u8 *iv;
+ u8 *tail;
+ int blksize;
+ int clen;
+ int alen;
+ int plen;
+ int tfclen;
+ int nfrags;
+ int assoclen;
+ int sglists;
+ int seqhilen;
+ __be32 *seqhi;
+
+ /* skb is pure payload to encrypt */
+
+ aead = x->data;
+ alen = crypto_aead_authsize(aead);
+
+ tfclen = 0;
+ if (x->tfcpad) {
+ struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb);
+ u32 padto;
+
+ padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached));
+ if (skb->len < padto)
+ tfclen = padto - skb->len;
+ }
+ blksize = ALIGN(crypto_aead_blocksize(aead), 4);
+ clen = ALIGN(skb->len + 2 + tfclen, blksize);
+ plen = clen - skb->len - tfclen;
+
+ err = skb_cow_data(skb, tfclen + plen + alen, &trailer);
+ if (err < 0)
+ goto error;
+ nfrags = err;
+
+ assoclen = sizeof(*esph);
+ sglists = 1;
+ seqhilen = 0;
+
+ if (x->props.flags & XFRM_STATE_ESN) {
+ sglists += 2;
+ seqhilen += sizeof(__be32);
+ assoclen += seqhilen;
+ }
+
+ tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen);
+ if (!tmp) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ seqhi = esp_tmp_seqhi(tmp);
+ iv = esp_tmp_iv(aead, tmp, seqhilen);
+ req = esp_tmp_givreq(aead, iv);
+ asg = esp_givreq_sg(aead, req);
+ sg = asg + sglists;
+
+ /* Fill padding... */
+ tail = skb_tail_pointer(trailer);
+ 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] = *skb_mac_header(skb);
+ pskb_put(skb, trailer, clen - skb->len + alen);
+
+ skb_push(skb, -skb_network_offset(skb));
+ esph = ip_esp_hdr(skb);
+ *skb_mac_header(skb) = IPPROTO_ESP;
+
+ /* this is non-NULL only with UDP Encapsulation */
+ if (x->encap) {
+ struct xfrm_encap_tmpl *encap = x->encap;
+ struct udphdr *uh;
+ __be32 *udpdata32;
+ __be16 sport, dport;
+ int encap_type;
+
+ spin_lock_bh(&x->lock);
+ sport = encap->encap_sport;
+ dport = encap->encap_dport;
+ encap_type = encap->encap_type;
+ spin_unlock_bh(&x->lock);
+
+ uh = (struct udphdr *)esph;
+ uh->source = sport;
+ uh->dest = dport;
+ uh->len = htons(skb->len - skb_transport_offset(skb));
+ uh->check = 0;
+
+ switch (encap_type) {
+ default:
+ case UDP_ENCAP_ESPINUDP:
+ esph = (struct ip_esp_hdr *)(uh + 1);
+ break;
+ case UDP_ENCAP_ESPINUDP_NON_IKE:
+ udpdata32 = (__be32 *)(uh + 1);
+ udpdata32[0] = udpdata32[1] = 0;
+ esph = (struct ip_esp_hdr *)(udpdata32 + 2);
+ break;
+ }
+
+ *skb_mac_header(skb) = IPPROTO_UDP;
+ }
+
+ esph->spi = x->id.spi;
+ esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
+
+ sg_init_table(sg, nfrags);
+ skb_to_sgvec(skb, sg,
+ esph->enc_data + crypto_aead_ivsize(aead) - skb->data,
+ clen + alen);
+
+ if ((x->props.flags & XFRM_STATE_ESN)) {
+ sg_init_table(asg, 3);
+ sg_set_buf(asg, &esph->spi, sizeof(__be32));
+ *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
+ sg_set_buf(asg + 1, seqhi, seqhilen);
+ sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32));
+ } else
+ sg_init_one(asg, esph, sizeof(*esph));
+
+ aead_givcrypt_set_callback(req, 0, esp_output_done, skb);
+ aead_givcrypt_set_crypt(req, sg, sg, clen, iv);
+ aead_givcrypt_set_assoc(req, asg, assoclen);
+ aead_givcrypt_set_giv(req, esph->enc_data,
+ XFRM_SKB_CB(skb)->seq.output.low +
+ ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32));
+
+ ESP_SKB_CB(skb)->tmp = tmp;
+ err = crypto_aead_givencrypt(req);
+ if (err == -EINPROGRESS)
+ goto error;
+
+ if (err == -EBUSY)
+ err = NET_XMIT_DROP;
+
+ kfree(tmp);
+
+error:
+ return err;
+}
+
+static int esp_input_done2(struct sk_buff *skb, int err)
+{
+ const struct iphdr *iph;
+ struct xfrm_state *x = xfrm_input_state(skb);
+ struct crypto_aead *aead = x->data;
+ int alen = crypto_aead_authsize(aead);
+ int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead);
+ int elen = skb->len - hlen;
+ int ihl;
+ u8 nexthdr[2];
+ int padlen;
+
+ kfree(ESP_SKB_CB(skb)->tmp);
+
+ if (unlikely(err))
+ goto out;
+
+ if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2))
+ BUG();
+
+ err = -EINVAL;
+ padlen = nexthdr[0];
+ if (padlen + 2 + alen >= elen)
+ goto out;
+
+ /* ... check padding bits here. Silly. :-) */
+
+ iph = ip_hdr(skb);
+ ihl = iph->ihl * 4;
+
+ if (x->encap) {
+ struct xfrm_encap_tmpl *encap = x->encap;
+ struct udphdr *uh = (void *)(skb_network_header(skb) + ihl);
+
+ /*
+ * 1) if the NAT-T peer's IP or port changed then
+ * advertize the change to the keying daemon.
+ * This is an inbound SA, so just compare
+ * SRC ports.
+ */
+ if (iph->saddr != x->props.saddr.a4 ||
+ uh->source != encap->encap_sport) {
+ xfrm_address_t ipaddr;
+
+ ipaddr.a4 = iph->saddr;
+ km_new_mapping(x, &ipaddr, uh->source);
+
+ /* XXX: perhaps add an extra
+ * policy check here, to see
+ * if we should allow or
+ * reject a packet from a
+ * different source
+ * address/port.
+ */
+ }
+
+ /*
+ * 2) ignore UDP/TCP checksums in case
+ * of NAT-T in Transport Mode, or
+ * perform other post-processing fixes
+ * as per draft-ietf-ipsec-udp-encaps-06,
+ * section 3.1.2
+ */
+ if (x->props.mode == XFRM_MODE_TRANSPORT)
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ }
+
+ pskb_trim(skb, skb->len - alen - padlen - 2);
+ __skb_pull(skb, hlen);
+ if (x->props.mode == XFRM_MODE_TUNNEL)
+ skb_reset_transport_header(skb);
+ else
+ skb_set_transport_header(skb, -ihl);
+
+ err = nexthdr[1];
+
+ /* RFC4303: Drop dummy packets without any error */
+ if (err == IPPROTO_NONE)
+ err = -EINVAL;
+
+out:
+ return err;
+}
+
+static void esp_input_done(struct crypto_async_request *base, int err)
+{
+ struct sk_buff *skb = base->data;
+
+ xfrm_input_resume(skb, esp_input_done2(skb, err));
+}
+
+/*
+ * Note: detecting truncated vs. non-truncated authentication data is very
+ * expensive, so we only support truncated data, which is the recommended
+ * and common case.
+ */
+static int esp_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 elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead);
+ int nfrags;
+ int assoclen;
+ int sglists;
+ int seqhilen;
+ __be32 *seqhi;
+ void *tmp;
+ u8 *iv;
+ struct scatterlist *sg;
+ struct scatterlist *asg;
+ int err = -EINVAL;
+
+ if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
+ goto out;
+
+ if (elen <= 0)
+ goto out;
+
+ err = skb_cow_data(skb, 0, &trailer);
+ if (err < 0)
+ goto out;
+
+ nfrags = err;
+
+ assoclen = sizeof(*esph);
+ sglists = 1;
+ seqhilen = 0;
+
+ if (x->props.flags & XFRM_STATE_ESN) {
+ sglists += 2;
+ seqhilen += sizeof(__be32);
+ assoclen += seqhilen;
+ }
+
+ err = -ENOMEM;
+ tmp = esp_alloc_tmp(aead, nfrags + sglists, 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);
+ asg = esp_req_sg(aead, req);
+ sg = asg + sglists;
+
+ skb->ip_summed = CHECKSUM_NONE;
+
+ esph = (struct ip_esp_hdr *)skb->data;
+
+ /* Get ivec. This can be wrong, check against another impls. */
+ iv = esph->enc_data;
+
+ sg_init_table(sg, nfrags);
+ skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen);
+
+ if ((x->props.flags & XFRM_STATE_ESN)) {
+ sg_init_table(asg, 3);
+ sg_set_buf(asg, &esph->spi, sizeof(__be32));
+ *seqhi = XFRM_SKB_CB(skb)->seq.input.hi;
+ sg_set_buf(asg + 1, seqhi, seqhilen);
+ sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32));
+ } else
+ sg_init_one(asg, esph, sizeof(*esph));
+
+ aead_request_set_callback(req, 0, esp_input_done, skb);
+ aead_request_set_crypt(req, sg, sg, elen, iv);
+ aead_request_set_assoc(req, asg, assoclen);
+
+ err = crypto_aead_decrypt(req);
+ if (err == -EINPROGRESS)
+ goto out;
+
+ err = esp_input_done2(skb, err);
+
+out:
+ return err;
+}
+
+static u32 esp4_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;
+
+ switch (x->props.mode) {
+ case XFRM_MODE_TRANSPORT:
+ case XFRM_MODE_BEET:
+ net_adj = sizeof(struct iphdr);
+ break;
+ case XFRM_MODE_TUNNEL:
+ net_adj = 0;
+ break;
+ default:
+ BUG();
+ }
+
+ return ((mtu - x->props.header_len - crypto_aead_authsize(aead) -
+ net_adj) & ~(blksize - 1)) + net_adj - 2;
+}
+
+static int esp4_err(struct sk_buff *skb, u32 info)
+{
+ struct net *net = dev_net(skb->dev);
+ const struct iphdr *iph = (const struct iphdr *)skb->data;
+ struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2));
+ struct xfrm_state *x;
+
+ switch (icmp_hdr(skb)->type) {
+ case ICMP_DEST_UNREACH:
+ if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
+ return 0;
+ case ICMP_REDIRECT:
+ break;
+ default:
+ return 0;
+ }
+
+ x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
+ esph->spi, IPPROTO_ESP, AF_INET);
+ if (!x)
+ return 0;
+
+ if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
+ ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0);
+ else
+ ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0);
+ xfrm_state_put(x);
+
+ return 0;
+}
+
+static void esp_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)
+{
+ struct crypto_aead *aead;
+ int err;
+
+ aead = crypto_alloc_aead(x->aead->alg_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,
+ "authencesn(%s,%s)",
+ x->aalg ? x->aalg->alg_name : "digest_null",
+ x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME)
+ goto error;
+ } else {
+ if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME,
+ "authenc(%s,%s)",
+ x->aalg ? x->aalg->alg_name : "digest_null",
+ x->ealg->alg_name) >= 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 esp_init_state(struct xfrm_state *x)
+{
+ struct crypto_aead *aead;
+ u32 align;
+ int err;
+
+ 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);
+ if (x->props.mode == XFRM_MODE_TUNNEL)
+ x->props.header_len += sizeof(struct iphdr);
+ else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6)
+ x->props.header_len += IPV4_BEET_PHMAXLEN;
+ if (x->encap) {
+ struct xfrm_encap_tmpl *encap = x->encap;
+
+ switch (encap->encap_type) {
+ default:
+ goto error;
+ case UDP_ENCAP_ESPINUDP:
+ x->props.header_len += sizeof(struct udphdr);
+ break;
+ case UDP_ENCAP_ESPINUDP_NON_IKE:
+ x->props.header_len += sizeof(struct udphdr) + 2 * sizeof(u32);
+ break;
+ }
+ }
+
+ align = ALIGN(crypto_aead_blocksize(aead), 4);
+ x->props.trailer_len = align + 1 + crypto_aead_authsize(aead);
+
+error:
+ return err;
+}
+
+static int esp4_rcv_cb(struct sk_buff *skb, int err)
+{
+ return 0;
+}
+
+static const struct xfrm_type esp_type =
+{
+ .description = "ESP4",
+ .owner = THIS_MODULE,
+ .proto = IPPROTO_ESP,
+ .flags = XFRM_TYPE_REPLAY_PROT,
+ .init_state = esp_init_state,
+ .destructor = esp_destroy,
+ .get_mtu = esp4_get_mtu,
+ .input = esp_input,
+ .output = esp_output
+};
+
+static struct xfrm4_protocol esp4_protocol = {
+ .handler = xfrm4_rcv,
+ .input_handler = xfrm_input,
+ .cb_handler = esp4_rcv_cb,
+ .err_handler = esp4_err,
+ .priority = 0,
+};
+
+static int __init esp4_init(void)
+{
+ if (xfrm_register_type(&esp_type, AF_INET) < 0) {
+ pr_info("%s: can't add xfrm type\n", __func__);
+ return -EAGAIN;
+ }
+ if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) {
+ pr_info("%s: can't add protocol\n", __func__);
+ xfrm_unregister_type(&esp_type, AF_INET);
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+static void __exit esp4_fini(void)
+{
+ if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0)
+ pr_info("%s: can't remove protocol\n", __func__);
+ if (xfrm_unregister_type(&esp_type, AF_INET) < 0)
+ pr_info("%s: can't remove xfrm type\n", __func__);
+}
+
+module_init(esp4_init);
+module_exit(esp4_fini);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP);