esp: Add gso handlers for esp4 and esp6

This patch extends the xfrm_type by an encap function pointer
and implements esp4_gso_encap and esp6_gso_encap. These functions
doing the basic esp encapsulation for a GSO packet. In case the
GSO packet needs to be segmented in software, we add gso_segment
functions. This codepath is going to be used on esp hardware
offloads.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 91e6a40..4382f30 100644 (file)
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -161,11 +161,19 @@ static struct ip_esp_hdr *esp_output_set_extra(struct sk_buff *skb,
         * encryption.
         */
        if ((x->props.flags & XFRM_STATE_ESN)) {
+               __u32 seqhi;
+               struct xfrm_offload *xo = xfrm_offload(skb);
+
+               if (xo)
+                       seqhi = xo->seq.hi;
+               else
+                       seqhi = XFRM_SKB_CB(skb)->seq.output.hi;
+
                extra->esphoff = (unsigned char *)esph -
                                 skb_transport_header(skb);
                esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4);
                extra->seqhi = esph->spi;
-               esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
+               esph->seq_no = htonl(seqhi);
        }
 
        esph->spi = x->id.spi;

diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c
index efaaa44..1e39564 100644 (file)
--- a/net/ipv4/esp4_offload.c
+++ b/net/ipv4/esp4_offload.c
@@ -84,6 +84,97 @@ out:
        return NULL;
 }
 
+static void esp4_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
+{
+       struct ip_esp_hdr *esph;
+       struct iphdr *iph = ip_hdr(skb);
+       struct xfrm_offload *xo = xfrm_offload(skb);
+       int proto = iph->protocol;
+
+       skb_push(skb, -skb_network_offset(skb));
+       esph = ip_esp_hdr(skb);
+       *skb_mac_header(skb) = IPPROTO_ESP;
+
+       esph->spi = x->id.spi;
+       esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
+
+       xo->proto = proto;
+}
+
+static struct sk_buff *esp4_gso_segment(struct sk_buff *skb,
+                                       netdev_features_t features)
+{
+       __u32 seq;
+       int err = 0;
+       struct sk_buff *skb2;
+       struct xfrm_state *x;
+       struct ip_esp_hdr *esph;
+       struct crypto_aead *aead;
+       struct sk_buff *segs = ERR_PTR(-EINVAL);
+       netdev_features_t esp_features = features;
+       struct xfrm_offload *xo = xfrm_offload(skb);
+
+       if (!xo)
+               goto out;
+
+       seq = xo->seq.low;
+
+       x = skb->sp->xvec[skb->sp->len - 1];
+       aead = x->data;
+       esph = ip_esp_hdr(skb);
+
+       if (esph->spi != x->id.spi)
+               goto out;
+
+       if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
+               goto out;
+
+       __skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
+
+       skb->encap_hdr_csum = 1;
+
+       if (!(features & NETIF_F_HW_ESP))
+               esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
+
+       segs = x->outer_mode->gso_segment(x, skb, esp_features);
+       if (IS_ERR_OR_NULL(segs))
+               goto out;
+
+       __skb_pull(skb, skb->data - skb_mac_header(skb));
+
+       skb2 = segs;
+       do {
+               struct sk_buff *nskb = skb2->next;
+
+               xo = xfrm_offload(skb2);
+               xo->flags |= XFRM_GSO_SEGMENT;
+               xo->seq.low = seq;
+               xo->seq.hi = xfrm_replay_seqhi(x, seq);
+
+               if(!(features & NETIF_F_HW_ESP))
+                       xo->flags |= CRYPTO_FALLBACK;
+
+               x->outer_mode->xmit(x, skb2);
+
+               err = x->type_offload->xmit(x, skb2, esp_features);
+               if (err) {
+                       kfree_skb_list(segs);
+                       return ERR_PTR(err);
+               }
+
+               if (!skb_is_gso(skb2))
+                       seq++;
+               else
+                       seq += skb_shinfo(skb2)->gso_segs;
+
+               skb_push(skb2, skb2->mac_len);
+               skb2 = nskb;
+       } while (skb2);
+
+out:
+       return segs;
+}
+
 static int esp_input_tail(struct xfrm_state *x, struct sk_buff *skb)
 {
        struct crypto_aead *aead = x->data;
@@ -173,6 +264,7 @@ static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb,  netdev_features_
 static const struct net_offload esp4_offload = {
        .callbacks = {
                .gro_receive = esp4_gro_receive,
+               .gso_segment = esp4_gso_segment,
        },
 };
 
@@ -182,6 +274,7 @@ static const struct xfrm_type_offload esp_type_offload = {
        .proto          = IPPROTO_ESP,
        .input_tail     = esp_input_tail,
        .xmit           = esp_xmit,
+       .encap          = esp4_gso_encap,
 };
 
 static int __init esp4_offload_init(void)

diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index cc654a7..82d3da8 100644 (file)
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -179,9 +179,14 @@ static struct ip_esp_hdr *esp_output_set_esn(struct sk_buff *skb,
         * 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;
-               esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi);
+               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;
@@ -223,7 +228,6 @@ int esp6_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info
        struct sk_buff *trailer;
        int tailen = esp->tailen;
 
-       *skb_mac_header(skb) = IPPROTO_ESP;
        esph = ip_esp_hdr(skb);
 
        if (!skb_cloned(skb)) {

diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c
index 5dd20c0..06e9721 100644 (file)
--- a/net/ipv6/esp6_offload.c
+++ b/net/ipv6/esp6_offload.c
@@ -86,6 +86,97 @@ out:
        return NULL;
 }
 
+static void esp6_gso_encap(struct xfrm_state *x, struct sk_buff *skb)
+{
+       struct ip_esp_hdr *esph;
+       struct ipv6hdr *iph = ipv6_hdr(skb);
+       struct xfrm_offload *xo = xfrm_offload(skb);
+       int proto = iph->nexthdr;
+
+       skb_push(skb, -skb_network_offset(skb));
+       esph = ip_esp_hdr(skb);
+       *skb_mac_header(skb) = IPPROTO_ESP;
+
+       esph->spi = x->id.spi;
+       esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low);
+
+       xo->proto = proto;
+}
+
+static struct sk_buff *esp6_gso_segment(struct sk_buff *skb,
+                                       netdev_features_t features)
+{
+       __u32 seq;
+       int err = 0;
+       struct sk_buff *skb2;
+       struct xfrm_state *x;
+       struct ip_esp_hdr *esph;
+       struct crypto_aead *aead;
+       struct sk_buff *segs = ERR_PTR(-EINVAL);
+       netdev_features_t esp_features = features;
+       struct xfrm_offload *xo = xfrm_offload(skb);
+
+       if (xo)
+               goto out;
+
+       seq = xo->seq.low;
+
+       x = skb->sp->xvec[skb->sp->len - 1];
+       aead = x->data;
+       esph = ip_esp_hdr(skb);
+
+       if (esph->spi != x->id.spi)
+               goto out;
+
+       if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead)))
+               goto out;
+
+       __skb_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead));
+
+       skb->encap_hdr_csum = 1;
+
+       if (!(features & NETIF_F_HW_ESP))
+               esp_features = features & ~(NETIF_F_SG | NETIF_F_CSUM_MASK);
+
+       segs = x->outer_mode->gso_segment(x, skb, esp_features);
+       if (IS_ERR_OR_NULL(segs))
+               goto out;
+
+       __skb_pull(skb, skb->data - skb_mac_header(skb));
+
+       skb2 = segs;
+       do {
+               struct sk_buff *nskb = skb2->next;
+
+               xo = xfrm_offload(skb2);
+               xo->flags |= XFRM_GSO_SEGMENT;
+               xo->seq.low = seq;
+               xo->seq.hi = xfrm_replay_seqhi(x, seq);
+
+               if(!(features & NETIF_F_HW_ESP))
+                       xo->flags |= CRYPTO_FALLBACK;
+
+               x->outer_mode->xmit(x, skb2);
+
+               err = x->type_offload->xmit(x, skb2, esp_features);
+               if (err) {
+                       kfree_skb_list(segs);
+                       return ERR_PTR(err);
+               }
+
+               if (!skb_is_gso(skb2))
+                       seq++;
+               else
+                       seq += skb_shinfo(skb2)->gso_segs;
+
+               skb_push(skb2, skb2->mac_len);
+               skb2 = nskb;
+       } while (skb2);
+
+out:
+       return segs;
+}
+
 static int esp6_input_tail(struct xfrm_state *x, struct sk_buff *skb)
 {
        struct crypto_aead *aead = x->data;
@@ -176,6 +267,7 @@ static int esp6_xmit(struct xfrm_state *x, struct sk_buff *skb,  netdev_features
 static const struct net_offload esp6_offload = {
        .callbacks = {
                .gro_receive = esp6_gro_receive,
+               .gso_segment = esp6_gso_segment,
        },
 };
 
@@ -185,6 +277,7 @@ static const struct xfrm_type_offload esp6_type_offload = {
        .proto          = IPPROTO_ESP,
        .input_tail     = esp6_input_tail,
        .xmit           = esp6_xmit,
+       .encap          = esp6_gso_encap,
 };
 
 static int __init esp6_offload_init(void)

diff --git a/net/xfrm/xfrm_replay.c b/net/xfrm/xfrm_replay.c
index cdc2e2e..20e68a3 100644 (file)
--- a/net/xfrm/xfrm_replay.c
+++ b/net/xfrm/xfrm_replay.c
@@ -45,7 +45,8 @@ u32 xfrm_replay_seqhi(struct xfrm_state *x, __be32 net_seq)
 
        return seq_hi;
 }
-
+EXPORT_SYMBOL(xfrm_replay_seqhi);
+;
 static void xfrm_replay_notify(struct xfrm_state *x, int event)
 {
        struct km_event c;