xfrm: Prepare the GRO codepath for hardware offloading.

On IPsec hardware offloading, we already get a secpath with
valid state attached when the packet enters the GRO handlers.
So check for hardware offload and skip the state lookup in this
case.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

net/ipv4/esp4_offload.c

@@ -43,27 +43,31 @@ static struct sk_buff **esp4_gro_receive(struct sk_buff **head,
 	if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0)
 		goto out;
 
-	err = secpath_set(skb);
-	if (err)
-		goto out;
-
-	if (skb->sp->len == XFRM_MAX_DEPTH)
-		goto out;
-
-	x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
-			      (xfrm_address_t *)&ip_hdr(skb)->daddr,
-			      spi, IPPROTO_ESP, AF_INET);
-	if (!x)
-		goto out;
-
-	skb->sp->xvec[skb->sp->len++] = x;
-	skb->sp->olen++;
-
 	xo = xfrm_offload(skb);
-	if (!xo) {
-		xfrm_state_put(x);
-		goto out;
+	if (!xo || !(xo->flags & CRYPTO_DONE)) {
+		err = secpath_set(skb);
+		if (err)
+			goto out;
+
+		if (skb->sp->len == XFRM_MAX_DEPTH)
+			goto out;
+
+		x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
+				      (xfrm_address_t *)&ip_hdr(skb)->daddr,
+				      spi, IPPROTO_ESP, AF_INET);
+		if (!x)
+			goto out;
+
+		skb->sp->xvec[skb->sp->len++] = x;
+		skb->sp->olen++;
+
+		xo = xfrm_offload(skb);
+		if (!xo) {
+			xfrm_state_put(x);
+			goto out;
+		}
 	}
+
 	xo->flags |= XFRM_GRO;
 
 	XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL;

net/ipv6/esp6_offload.c

@@ -45,27 +45,31 @@ static struct sk_buff **esp6_gro_receive(struct sk_buff **head,
 	if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0)
 		goto out;
 
-	err = secpath_set(skb);
-	if (err)
-		goto out;
-
-	if (skb->sp->len == XFRM_MAX_DEPTH)
-		goto out;
-
-	x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
-			      (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
-			      spi, IPPROTO_ESP, AF_INET6);
-	if (!x)
-		goto out;
-
-	skb->sp->xvec[skb->sp->len++] = x;
-	skb->sp->olen++;
-
 	xo = xfrm_offload(skb);
-	if (!xo) {
-		xfrm_state_put(x);
-		goto out;
+	if (!xo || !(xo->flags & CRYPTO_DONE)) {
+		err = secpath_set(skb);
+		if (err)
+			goto out;
+
+		if (skb->sp->len == XFRM_MAX_DEPTH)
+			goto out;
+
+		x = xfrm_state_lookup(dev_net(skb->dev), skb->mark,
+				      (xfrm_address_t *)&ipv6_hdr(skb)->daddr,
+				      spi, IPPROTO_ESP, AF_INET6);
+		if (!x)
+			goto out;
+
+		skb->sp->xvec[skb->sp->len++] = x;
+		skb->sp->olen++;
+
+		xo = xfrm_offload(skb);
+		if (!xo) {
+			xfrm_state_put(x);
+			goto out;
+		}
 	}
+
 	xo->flags |= XFRM_GRO;
 
 	XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = NULL;

net/xfrm/xfrm_input.c

@@ -223,38 +223,38 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 			seq = XFRM_SKB_CB(skb)->seq.input.low;
 			goto resume;
 		}
+
 		/* encap_type < -1 indicates a GRO call. */
 		encap_type = 0;
 		seq = XFRM_SPI_SKB_CB(skb)->seq;
-		goto lock;
-	}
-
-	if (xo && (xo->flags & CRYPTO_DONE)) {
-		crypto_done = true;
-		x = xfrm_input_state(skb);
-		family = XFRM_SPI_SKB_CB(skb)->family;
 
-		if (!(xo->status & CRYPTO_SUCCESS)) {
-			if (xo->status &
-			    (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
-			     CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
-			     CRYPTO_TUNNEL_AH_AUTH_FAILED |
-			     CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
-
-				xfrm_audit_state_icvfail(x, skb,
-							 x->type->proto);
-				x->stats.integrity_failed++;
-				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
+		if (xo && (xo->flags & CRYPTO_DONE)) {
+			crypto_done = true;
+			x = xfrm_input_state(skb);
+			family = XFRM_SPI_SKB_CB(skb)->family;
+
+			if (!(xo->status & CRYPTO_SUCCESS)) {
+				if (xo->status &
+				    (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
+				     CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
+				     CRYPTO_TUNNEL_AH_AUTH_FAILED |
+				     CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
+
+					xfrm_audit_state_icvfail(x, skb,
+								 x->type->proto);
+					x->stats.integrity_failed++;
+					XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
+					goto drop;
+				}
+
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 				goto drop;
 			}
 
-			XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
-			goto drop;
-		}
-
-		if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
-			XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
-			goto drop;
+			if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
+				goto drop;
+			}
 		}
 
 		goto lock;