1064 строки
24 KiB
C
1064 строки
24 KiB
C
#define pr_fmt(fmt) "IPsec: " fmt
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#include <crypto/aead.h>
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#include <crypto/authenc.h>
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#include <linux/err.h>
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#include <linux/module.h>
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#include <net/ip.h>
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#include <net/xfrm.h>
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#include <net/esp.h>
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#include <linux/scatterlist.h>
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#include <linux/kernel.h>
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#include <linux/pfkeyv2.h>
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#include <linux/rtnetlink.h>
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#include <linux/slab.h>
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#include <linux/spinlock.h>
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#include <linux/in6.h>
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#include <net/icmp.h>
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#include <net/protocol.h>
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#include <net/udp.h>
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#include <linux/highmem.h>
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struct esp_skb_cb {
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struct xfrm_skb_cb xfrm;
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void *tmp;
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};
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struct esp_output_extra {
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__be32 seqhi;
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u32 esphoff;
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};
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#define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0]))
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static u32 esp4_get_mtu(struct xfrm_state *x, int mtu);
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/*
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* Allocate an AEAD request structure with extra space for SG and IV.
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*
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* For alignment considerations the IV is placed at the front, followed
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* by the request and finally the SG list.
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*
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* TODO: Use spare space in skb for this where possible.
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*/
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static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int extralen)
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{
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unsigned int len;
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len = extralen;
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len += crypto_aead_ivsize(aead);
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if (len) {
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len += crypto_aead_alignmask(aead) &
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~(crypto_tfm_ctx_alignment() - 1);
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len = ALIGN(len, crypto_tfm_ctx_alignment());
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}
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len += sizeof(struct aead_request) + crypto_aead_reqsize(aead);
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len = ALIGN(len, __alignof__(struct scatterlist));
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len += sizeof(struct scatterlist) * nfrags;
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return kmalloc(len, GFP_ATOMIC);
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}
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static inline void *esp_tmp_extra(void *tmp)
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{
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return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra));
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}
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static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int extralen)
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{
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return crypto_aead_ivsize(aead) ?
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PTR_ALIGN((u8 *)tmp + extralen,
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crypto_aead_alignmask(aead) + 1) : tmp + extralen;
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}
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static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv)
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{
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struct aead_request *req;
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req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead),
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crypto_tfm_ctx_alignment());
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aead_request_set_tfm(req, aead);
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return req;
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}
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static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead,
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struct aead_request *req)
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{
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return (void *)ALIGN((unsigned long)(req + 1) +
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crypto_aead_reqsize(aead),
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__alignof__(struct scatterlist));
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}
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static void esp_ssg_unref(struct xfrm_state *x, void *tmp)
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{
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struct esp_output_extra *extra = esp_tmp_extra(tmp);
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struct crypto_aead *aead = x->data;
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int extralen = 0;
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u8 *iv;
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struct aead_request *req;
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struct scatterlist *sg;
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if (x->props.flags & XFRM_STATE_ESN)
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extralen += sizeof(*extra);
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extra = esp_tmp_extra(tmp);
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iv = esp_tmp_iv(aead, tmp, extralen);
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req = esp_tmp_req(aead, iv);
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/* Unref skb_frag_pages in the src scatterlist if necessary.
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* Skip the first sg which comes from skb->data.
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*/
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if (req->src != req->dst)
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for (sg = sg_next(req->src); sg; sg = sg_next(sg))
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put_page(sg_page(sg));
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}
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static void esp_output_done(struct crypto_async_request *base, int err)
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{
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struct sk_buff *skb = base->data;
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struct xfrm_offload *xo = xfrm_offload(skb);
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void *tmp;
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struct xfrm_state *x;
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if (xo && (xo->flags & XFRM_DEV_RESUME))
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x = skb->sp->xvec[skb->sp->len - 1];
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else
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x = skb_dst(skb)->xfrm;
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tmp = ESP_SKB_CB(skb)->tmp;
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esp_ssg_unref(x, tmp);
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kfree(tmp);
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if (xo && (xo->flags & XFRM_DEV_RESUME)) {
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if (err) {
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XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
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kfree_skb(skb);
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return;
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}
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skb_push(skb, skb->data - skb_mac_header(skb));
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secpath_reset(skb);
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xfrm_dev_resume(skb);
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} else {
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xfrm_output_resume(skb, err);
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}
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}
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/* Move ESP header back into place. */
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static void esp_restore_header(struct sk_buff *skb, unsigned int offset)
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{
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struct ip_esp_hdr *esph = (void *)(skb->data + offset);
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void *tmp = ESP_SKB_CB(skb)->tmp;
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__be32 *seqhi = esp_tmp_extra(tmp);
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esph->seq_no = esph->spi;
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esph->spi = *seqhi;
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}
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static void esp_output_restore_header(struct sk_buff *skb)
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{
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void *tmp = ESP_SKB_CB(skb)->tmp;
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struct esp_output_extra *extra = esp_tmp_extra(tmp);
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esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff -
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sizeof(__be32));
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}
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static struct ip_esp_hdr *esp_output_set_extra(struct sk_buff *skb,
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struct xfrm_state *x,
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struct ip_esp_hdr *esph,
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struct esp_output_extra *extra)
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{
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/* For ESN we move the header forward by 4 bytes to
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* accomodate the high bits. We will move it back after
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* encryption.
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*/
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if ((x->props.flags & XFRM_STATE_ESN)) {
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__u32 seqhi;
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struct xfrm_offload *xo = xfrm_offload(skb);
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if (xo)
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seqhi = xo->seq.hi;
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else
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seqhi = XFRM_SKB_CB(skb)->seq.output.hi;
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extra->esphoff = (unsigned char *)esph -
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skb_transport_header(skb);
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esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4);
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extra->seqhi = esph->spi;
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esph->seq_no = htonl(seqhi);
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}
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esph->spi = x->id.spi;
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return esph;
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}
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static void esp_output_done_esn(struct crypto_async_request *base, int err)
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{
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struct sk_buff *skb = base->data;
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esp_output_restore_header(skb);
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esp_output_done(base, err);
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}
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static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto)
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{
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/* Fill padding... */
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if (tfclen) {
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memset(tail, 0, tfclen);
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tail += tfclen;
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}
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do {
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int i;
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for (i = 0; i < plen - 2; i++)
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tail[i] = i + 1;
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} while (0);
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tail[plen - 2] = plen - 2;
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tail[plen - 1] = proto;
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}
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static void esp_output_udp_encap(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
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{
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int encap_type;
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struct udphdr *uh;
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__be32 *udpdata32;
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__be16 sport, dport;
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struct xfrm_encap_tmpl *encap = x->encap;
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struct ip_esp_hdr *esph = esp->esph;
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spin_lock_bh(&x->lock);
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sport = encap->encap_sport;
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dport = encap->encap_dport;
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encap_type = encap->encap_type;
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spin_unlock_bh(&x->lock);
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uh = (struct udphdr *)esph;
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uh->source = sport;
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uh->dest = dport;
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uh->len = htons(skb->len + esp->tailen
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- skb_transport_offset(skb));
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uh->check = 0;
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switch (encap_type) {
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default:
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case UDP_ENCAP_ESPINUDP:
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esph = (struct ip_esp_hdr *)(uh + 1);
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break;
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case UDP_ENCAP_ESPINUDP_NON_IKE:
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udpdata32 = (__be32 *)(uh + 1);
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udpdata32[0] = udpdata32[1] = 0;
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esph = (struct ip_esp_hdr *)(udpdata32 + 2);
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break;
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}
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*skb_mac_header(skb) = IPPROTO_UDP;
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esp->esph = esph;
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}
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int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
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{
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u8 *tail;
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u8 *vaddr;
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int nfrags;
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int esph_offset;
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struct page *page;
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struct sk_buff *trailer;
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int tailen = esp->tailen;
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/* this is non-NULL only with UDP Encapsulation */
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if (x->encap)
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esp_output_udp_encap(x, skb, esp);
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if (!skb_cloned(skb)) {
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if (tailen <= skb_tailroom(skb)) {
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nfrags = 1;
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trailer = skb;
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tail = skb_tail_pointer(trailer);
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goto skip_cow;
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} else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS)
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&& !skb_has_frag_list(skb)) {
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int allocsize;
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struct sock *sk = skb->sk;
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struct page_frag *pfrag = &x->xfrag;
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esp->inplace = false;
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allocsize = ALIGN(tailen, L1_CACHE_BYTES);
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spin_lock_bh(&x->lock);
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if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
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spin_unlock_bh(&x->lock);
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goto cow;
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}
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page = pfrag->page;
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get_page(page);
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vaddr = kmap_atomic(page);
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tail = vaddr + pfrag->offset;
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esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
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kunmap_atomic(vaddr);
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nfrags = skb_shinfo(skb)->nr_frags;
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__skb_fill_page_desc(skb, nfrags, page, pfrag->offset,
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tailen);
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skb_shinfo(skb)->nr_frags = ++nfrags;
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pfrag->offset = pfrag->offset + allocsize;
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spin_unlock_bh(&x->lock);
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nfrags++;
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skb->len += tailen;
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skb->data_len += tailen;
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skb->truesize += tailen;
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if (sk)
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refcount_add(tailen, &sk->sk_wmem_alloc);
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goto out;
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}
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}
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cow:
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esph_offset = (unsigned char *)esp->esph - skb_transport_header(skb);
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nfrags = skb_cow_data(skb, tailen, &trailer);
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if (nfrags < 0)
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goto out;
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tail = skb_tail_pointer(trailer);
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esp->esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset);
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skip_cow:
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esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
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pskb_put(skb, trailer, tailen);
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out:
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return nfrags;
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}
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EXPORT_SYMBOL_GPL(esp_output_head);
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int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
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{
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u8 *iv;
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int alen;
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void *tmp;
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int ivlen;
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int assoclen;
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int extralen;
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struct page *page;
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struct ip_esp_hdr *esph;
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struct crypto_aead *aead;
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struct aead_request *req;
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struct scatterlist *sg, *dsg;
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struct esp_output_extra *extra;
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int err = -ENOMEM;
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assoclen = sizeof(struct ip_esp_hdr);
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extralen = 0;
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if (x->props.flags & XFRM_STATE_ESN) {
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extralen += sizeof(*extra);
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assoclen += sizeof(__be32);
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}
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aead = x->data;
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alen = crypto_aead_authsize(aead);
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ivlen = crypto_aead_ivsize(aead);
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tmp = esp_alloc_tmp(aead, esp->nfrags + 2, extralen);
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if (!tmp)
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goto error;
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extra = esp_tmp_extra(tmp);
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iv = esp_tmp_iv(aead, tmp, extralen);
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req = esp_tmp_req(aead, iv);
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sg = esp_req_sg(aead, req);
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if (esp->inplace)
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dsg = sg;
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else
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dsg = &sg[esp->nfrags];
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esph = esp_output_set_extra(skb, x, esp->esph, extra);
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esp->esph = esph;
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sg_init_table(sg, esp->nfrags);
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err = skb_to_sgvec(skb, sg,
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(unsigned char *)esph - skb->data,
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assoclen + ivlen + esp->clen + alen);
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if (unlikely(err < 0))
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goto error_free;
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if (!esp->inplace) {
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int allocsize;
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struct page_frag *pfrag = &x->xfrag;
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allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES);
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spin_lock_bh(&x->lock);
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if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
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spin_unlock_bh(&x->lock);
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goto error_free;
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}
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skb_shinfo(skb)->nr_frags = 1;
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page = pfrag->page;
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get_page(page);
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/* replace page frags in skb with new page */
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__skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len);
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pfrag->offset = pfrag->offset + allocsize;
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spin_unlock_bh(&x->lock);
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sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1);
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err = skb_to_sgvec(skb, dsg,
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(unsigned char *)esph - skb->data,
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assoclen + ivlen + esp->clen + alen);
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if (unlikely(err < 0))
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goto error_free;
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}
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if ((x->props.flags & XFRM_STATE_ESN))
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aead_request_set_callback(req, 0, esp_output_done_esn, skb);
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else
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aead_request_set_callback(req, 0, esp_output_done, skb);
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aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv);
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aead_request_set_ad(req, assoclen);
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memset(iv, 0, ivlen);
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memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8),
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min(ivlen, 8));
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ESP_SKB_CB(skb)->tmp = tmp;
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err = crypto_aead_encrypt(req);
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switch (err) {
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case -EINPROGRESS:
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goto error;
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case -ENOSPC:
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err = NET_XMIT_DROP;
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break;
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case 0:
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if ((x->props.flags & XFRM_STATE_ESN))
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esp_output_restore_header(skb);
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}
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if (sg != dsg)
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esp_ssg_unref(x, tmp);
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error_free:
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kfree(tmp);
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error:
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return err;
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}
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EXPORT_SYMBOL_GPL(esp_output_tail);
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static int esp_output(struct xfrm_state *x, struct sk_buff *skb)
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{
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int alen;
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int blksize;
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struct ip_esp_hdr *esph;
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struct crypto_aead *aead;
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struct esp_info esp;
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esp.inplace = true;
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esp.proto = *skb_mac_header(skb);
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*skb_mac_header(skb) = IPPROTO_ESP;
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/* skb is pure payload to encrypt */
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aead = x->data;
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alen = crypto_aead_authsize(aead);
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esp.tfclen = 0;
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if (x->tfcpad) {
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struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb);
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u32 padto;
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padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached));
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if (skb->len < padto)
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esp.tfclen = padto - skb->len;
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}
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blksize = ALIGN(crypto_aead_blocksize(aead), 4);
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esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize);
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esp.plen = esp.clen - skb->len - esp.tfclen;
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esp.tailen = esp.tfclen + esp.plen + alen;
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esp.esph = ip_esp_hdr(skb);
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esp.nfrags = esp_output_head(x, skb, &esp);
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if (esp.nfrags < 0)
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return esp.nfrags;
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esph = esp.esph;
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esph->spi = x->id.spi;
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|
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 esp_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 esp_input_done2(struct sk_buff *skb, int err)
|
|
{
|
|
const struct iphdr *iph;
|
|
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 ihl;
|
|
|
|
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;
|
|
|
|
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;
|
|
}
|
|
|
|
skb_pull_rcsum(skb, hlen);
|
|
if (x->props.mode == XFRM_MODE_TUNNEL)
|
|
skb_reset_transport_header(skb);
|
|
else
|
|
skb_set_transport_header(skb, -ihl);
|
|
|
|
/* RFC4303: Drop dummy packets without any error */
|
|
if (err == IPPROTO_NONE)
|
|
err = -EINVAL;
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(esp_input_done2);
|
|
|
|
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));
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
/*
|
|
* 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 ivlen = crypto_aead_ivsize(aead);
|
|
int elen = skb->len - sizeof(*esph) - ivlen;
|
|
int nfrags;
|
|
int assoclen;
|
|
int seqhilen;
|
|
__be32 *seqhi;
|
|
void *tmp;
|
|
u8 *iv;
|
|
struct scatterlist *sg;
|
|
int err = -EINVAL;
|
|
|
|
if (!pskb_may_pull(skb, sizeof(*esph) + ivlen))
|
|
goto out;
|
|
|
|
if (elen <= 0)
|
|
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;
|
|
}
|
|
}
|
|
|
|
err = skb_cow_data(skb, 0, &trailer);
|
|
if (err < 0)
|
|
goto out;
|
|
|
|
nfrags = err;
|
|
|
|
skip_cow:
|
|
err = -ENOMEM;
|
|
tmp = esp_alloc_tmp(aead, nfrags, seqhilen);
|
|
if (!tmp)
|
|
goto out;
|
|
|
|
ESP_SKB_CB(skb)->tmp = tmp;
|
|
seqhi = esp_tmp_extra(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);
|
|
err = skb_to_sgvec(skb, sg, 0, skb->len);
|
|
if (unlikely(err < 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);
|
|
|
|
err = crypto_aead_decrypt(req);
|
|
if (err == -EINPROGRESS)
|
|
goto out;
|
|
|
|
if ((x->props.flags & XFRM_STATE_ESN))
|
|
esp_input_restore_header(skb);
|
|
|
|
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)
|
|
{
|
|
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 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:
|
|
err = -EINVAL;
|
|
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);
|