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authorSteffen Klassert <steffen.klassert@secunet.com>2017-04-14 10:06:42 +0200
committerSteffen Klassert <steffen.klassert@secunet.com>2017-04-14 10:06:42 +0200
commit383d0350f2cc5e5b3a2003c46e15c0b98432037b (patch)
treef4b07c11f388f014a9819147a17c4d4c63e6224b /net/ipv6/esp6.c
parentfca11ebde3f0d1c637550a9b231caa385ce35749 (diff)
downloadlinux-383d0350f2cc5e5b3a2003c46e15c0b98432037b.tar.bz2
esp6: Reorganize esp_output
We need a fallback for ESP at layer 2, so split esp6_output into generic functions that can be used at layer 3 and layer 2 and use them in esp_output. We also add esp6_xmit which is used for the layer 2 fallback. Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Diffstat (limited to 'net/ipv6/esp6.c')
-rw-r--r--net/ipv6/esp6.c264
1 files changed, 140 insertions, 124 deletions
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 5bd1dcc8d16b..cc654a7afd91 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -170,11 +170,10 @@ static void esp_output_restore_header(struct sk_buff *skb)
}
static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb,
+ struct xfrm_state *x,
struct ip_esp_hdr *esph,
__be32 *seqhi)
{
- struct xfrm_state *x = skb_dst(skb)->xfrm;
-
/* For ESN we move the header forward by 4 bytes to
* accomodate the high bits. We will move it back after
* encryption.
@@ -214,59 +213,15 @@ static void esp_output_fill_trailer(u8 *tail, int tfclen, int plen, __u8 proto)
tail[plen - 1] = proto;
}
-static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
+int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp)
{
- int err;
- struct ip_esp_hdr *esph;
- struct crypto_aead *aead;
- struct aead_request *req;
- struct scatterlist *sg, *dsg;
- struct sk_buff *trailer;
- struct page *page;
- void *tmp;
- int blksize;
- int clen;
- int alen;
- int plen;
- int ivlen;
- int tfclen;
- int nfrags;
- int assoclen;
- int seqhilen;
- int tailen;
- u8 *iv;
u8 *tail;
u8 *vaddr;
- __be32 *seqhi;
- __be64 seqno;
- __u8 proto = *skb_mac_header(skb);
-
- /* skb is pure payload to encrypt */
- aead = x->data;
- alen = crypto_aead_authsize(aead);
- ivlen = crypto_aead_ivsize(aead);
-
- 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)
- tfclen = padto - skb->len;
- }
- blksize = ALIGN(crypto_aead_blocksize(aead), 4);
- clen = ALIGN(skb->len + 2 + tfclen, blksize);
- plen = clen - skb->len - tfclen;
- tailen = tfclen + plen + alen;
-
- assoclen = sizeof(*esph);
- seqhilen = 0;
-
- if (x->props.flags & XFRM_STATE_ESN) {
- seqhilen += sizeof(__be32);
- assoclen += seqhilen;
- }
+ int nfrags;
+ struct page *page;
+ struct ip_esp_hdr *esph;
+ struct sk_buff *trailer;
+ int tailen = esp->tailen;
*skb_mac_header(skb) = IPPROTO_ESP;
esph = ip_esp_hdr(skb);
@@ -284,6 +239,8 @@ static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
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);
@@ -300,10 +257,12 @@ static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
tail = vaddr + pfrag->offset;
- esp_output_fill_trailer(tail, tfclen, plen, proto);
+ esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
kunmap_atomic(vaddr);
+ spin_unlock_bh(&x->lock);
+
nfrags = skb_shinfo(skb)->nr_frags;
__skb_fill_page_desc(skb, nfrags, page, pfrag->offset,
@@ -319,77 +278,56 @@ static int esp6_output(struct xfrm_state *x, struct sk_buff *skb)
if (sk)
atomic_add(tailen, &sk->sk_wmem_alloc);
- skb_push(skb, -skb_network_offset(skb));
-
- esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
- esph->spi = x->id.spi;
-
- tmp = esp_alloc_tmp(aead, nfrags + 2, seqhilen);
- if (!tmp) {
- spin_unlock_bh(&x->lock);
- err = -ENOMEM;
- 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);
- dsg = &sg[nfrags];
-
- esph = esp_output_set_esn(skb, esph, seqhi);
-
- sg_init_table(sg, nfrags);
- skb_to_sgvec(skb, sg,
- (unsigned char *)esph - skb->data,
- assoclen + ivlen + clen + alen);
-
- allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES);
-
- if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) {
- spin_unlock_bh(&x->lock);
- err = -ENOMEM;
- goto error;
- }
-
- 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;
-
- sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1);
- skb_to_sgvec(skb, dsg,
- (unsigned char *)esph - skb->data,
- assoclen + ivlen + clen + alen);
-
- spin_unlock_bh(&x->lock);
-
- goto skip_cow2;
+ goto out;
}
}
cow:
- err = skb_cow_data(skb, tailen, &trailer);
- if (err < 0)
- goto error;
- nfrags = err;
-
+ nfrags = skb_cow_data(skb, tailen, &trailer);
+ if (nfrags < 0)
+ goto out;
tail = skb_tail_pointer(trailer);
- esph = ip_esp_hdr(skb);
skip_cow:
- esp_output_fill_trailer(tail, tfclen, plen, proto);
+ esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto);
+ pskb_put(skb, trailer, tailen);
- pskb_put(skb, trailer, clen - skb->len + alen);
- skb_push(skb, -skb_network_offset(skb));
+out:
+ return nfrags;
+}
+EXPORT_SYMBOL_GPL(esp6_output_head);
- esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
- esph->spi = x->id.spi;
+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;
- tmp = esp_alloc_tmp(aead, nfrags, seqhilen);
+ 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) {
+ spin_unlock_bh(&x->lock);
err = -ENOMEM;
goto error;
}
@@ -398,29 +336,57 @@ skip_cow:
iv = esp_tmp_iv(aead, tmp, seqhilen);
req = esp_tmp_req(aead, iv);
sg = esp_req_sg(aead, req);
- dsg = sg;
- esph = esp_output_set_esn(skb, esph, seqhi);
+ if (esp->inplace)
+ dsg = sg;
+ else
+ dsg = &sg[esp->nfrags];
- sg_init_table(sg, nfrags);
+ esph = esp_output_set_esn(skb, x, ip_esp_hdr(skb), seqhi);
+
+ sg_init_table(sg, esp->nfrags);
skb_to_sgvec(skb, sg,
(unsigned char *)esph - skb->data,
- assoclen + ivlen + clen + alen);
+ assoclen + ivlen + esp->clen + alen);
+
+ 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);
+ err = -ENOMEM;
+ goto error;
+ }
+
+ 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);
+ skb_to_sgvec(skb, dsg,
+ (unsigned char *)esph - skb->data,
+ assoclen + ivlen + esp->clen + alen);
+ }
-skip_cow2:
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 + clen, iv);
+ aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv);
aead_request_set_ad(req, assoclen);
- seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low +
- ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32));
-
memset(iv, 0, ivlen);
- memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&seqno + 8 - min(ivlen, 8),
+ memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8),
min(ivlen, 8));
ESP_SKB_CB(skb)->tmp = tmp;
@@ -446,8 +412,57 @@ skip_cow2:
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 int esp6_input_done2(struct sk_buff *skb, int err)
+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);
@@ -494,6 +509,7 @@ static int esp6_input_done2(struct sk_buff *skb, int err)
out:
return err;
}
+EXPORT_SYMBOL_GPL(esp6_input_done2);
static void esp_input_done(struct crypto_async_request *base, int err)
{