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>
diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c
index d914eb9..5dd20c0 100644
--- a/net/ipv6/esp6_offload.c
+++ b/net/ipv6/esp6_offload.c
@@ -86,19 +86,122 @@
return NULL;
}
+static int esp6_input_tail(struct xfrm_state *x, struct sk_buff *skb)
+{
+ struct crypto_aead *aead = x->data;
+
+ if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead)))
+ return -EINVAL;
+
+ skb->ip_summed = CHECKSUM_NONE;
+
+ return esp6_input_done2(skb, 0);
+}
+
+static int esp6_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features)
+{
+ int err;
+ int alen;
+ int blksize;
+ struct xfrm_offload *xo;
+ struct ip_esp_hdr *esph;
+ struct crypto_aead *aead;
+ struct esp_info esp;
+ bool hw_offload = true;
+
+ esp.inplace = true;
+
+ xo = xfrm_offload(skb);
+
+ if (!xo)
+ return -EINVAL;
+
+ if (!(features & NETIF_F_HW_ESP) ||
+ (x->xso.offload_handle && x->xso.dev != skb->dev)) {
+ xo->flags |= CRYPTO_FALLBACK;
+ }
+
+ esp.proto = xo->proto;
+
+ /* skb is pure payload to encrypt */
+
+ aead = x->data;
+ alen = crypto_aead_authsize(aead);
+
+ esp.tfclen = 0;
+ /* XXX: Add support for tfc padding here. */
+
+ 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;
+
+ if (!hw_offload || (hw_offload && !skb_is_gso(skb))) {
+ 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;
+
+ skb_push(skb, -skb_network_offset(skb));
+
+ if (xo->flags & XFRM_GSO_SEGMENT) {
+ esph->seq_no = htonl(xo->seq.low);
+ } else {
+ int len;
+
+ len = skb->len - sizeof(struct ipv6hdr);
+ if (len > IPV6_MAXPLEN)
+ len = 0;
+
+ ipv6_hdr(skb)->payload_len = htons(len);
+ }
+
+ if (x->xso.offload_handle && !(xo->flags & CRYPTO_FALLBACK))
+ return 0;
+
+ esp.seqno = cpu_to_be64(xo->seq.low + ((u64)xo->seq.hi << 32));
+
+ err = esp6_output_tail(x, skb, &esp);
+ if (err < 0)
+ return err;
+
+ secpath_reset(skb);
+
+ return 0;
+}
+
static const struct net_offload esp6_offload = {
.callbacks = {
.gro_receive = esp6_gro_receive,
},
};
+static const struct xfrm_type_offload esp6_type_offload = {
+ .description = "ESP6 OFFLOAD",
+ .owner = THIS_MODULE,
+ .proto = IPPROTO_ESP,
+ .input_tail = esp6_input_tail,
+ .xmit = esp6_xmit,
+};
+
static int __init esp6_offload_init(void)
{
+ if (xfrm_register_type_offload(&esp6_type_offload, AF_INET6) < 0) {
+ pr_info("%s: can't add xfrm type offload\n", __func__);
+ return -EAGAIN;
+ }
+
return inet6_add_offload(&esp6_offload, IPPROTO_ESP);
}
static void __exit esp6_offload_exit(void)
{
+ if (xfrm_unregister_type_offload(&esp6_type_offload, AF_INET6) < 0)
+ pr_info("%s: can't remove xfrm type offload\n", __func__);
+
inet6_del_offload(&esp6_offload, IPPROTO_ESP);
}