Merge tag 'ipsec-next-2023-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next

Steffen Klassert says:

====================
ipsec-next 2023-04-19

1) Remove inner/outer modes from input/output path. These are
   not needed anymore. From Herbert Xu.

* tag 'ipsec-next-2023-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next:
  xfrm: Remove inner/outer modes from output path
  xfrm: Remove inner/outer modes from input path
====================

Link: https://lore.kernel.org/r/20230419075300.452227-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 34 insertions, 65 deletions

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 436d29640ac2..39fb91ff23d9 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -231,9 +231,6 @@ static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int err = -EINVAL;
 
-	if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
-		goto out;
-
 	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
 		goto out;
 
@@ -269,8 +266,6 @@ static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int err = -EINVAL;
 
-	if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
-		goto out;
 	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
 		goto out;
 
@@ -331,22 +326,26 @@ out:
  */
 static int
 xfrm_inner_mode_encap_remove(struct xfrm_state *x,
-			     const struct xfrm_mode *inner_mode,
 			     struct sk_buff *skb)
 {
-	switch (inner_mode->encap) {
+	switch (x->props.mode) {
 	case XFRM_MODE_BEET:
-		if (inner_mode->family == AF_INET)
+		switch (XFRM_MODE_SKB_CB(skb)->protocol) {
+		case IPPROTO_IPIP:
+		case IPPROTO_BEETPH:
 			return xfrm4_remove_beet_encap(x, skb);
-		if (inner_mode->family == AF_INET6)
+		case IPPROTO_IPV6:
 			return xfrm6_remove_beet_encap(x, skb);
+		}
 		break;
 	case XFRM_MODE_TUNNEL:
-		if (inner_mode->family == AF_INET)
+		switch (XFRM_MODE_SKB_CB(skb)->protocol) {
+		case IPPROTO_IPIP:
 			return xfrm4_remove_tunnel_encap(x, skb);
-		if (inner_mode->family == AF_INET6)
+		case IPPROTO_IPV6:
 			return xfrm6_remove_tunnel_encap(x, skb);
 		break;
+		}
 	}
 
 	WARN_ON_ONCE(1);
@@ -355,9 +354,7 @@ xfrm_inner_mode_encap_remove(struct xfrm_state *x,
 
 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 {
-	const struct xfrm_mode *inner_mode = &x->inner_mode;
-
-	switch (x->outer_mode.family) {
+	switch (x->props.family) {
 	case AF_INET:
 		xfrm4_extract_header(skb);
 		break;
@@ -369,17 +366,12 @@ static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 		return -EAFNOSUPPORT;
 	}
 
-	if (x->sel.family == AF_UNSPEC) {
-		inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
-		if (!inner_mode)
-			return -EAFNOSUPPORT;
-	}
-
-	switch (inner_mode->family) {
-	case AF_INET:
+	switch (XFRM_MODE_SKB_CB(skb)->protocol) {
+	case IPPROTO_IPIP:
+	case IPPROTO_BEETPH:
 		skb->protocol = htons(ETH_P_IP);
 		break;
-	case AF_INET6:
+	case IPPROTO_IPV6:
 		skb->protocol = htons(ETH_P_IPV6);
 		break;
 	default:
@@ -387,7 +379,7 @@ static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 		break;
 	}
 
-	return xfrm_inner_mode_encap_remove(x, inner_mode, skb);
+	return xfrm_inner_mode_encap_remove(x, skb);
 }
 
 /* Remove encapsulation header.
@@ -433,17 +425,16 @@ static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 }
 
 static int xfrm_inner_mode_input(struct xfrm_state *x,
-				 const struct xfrm_mode *inner_mode,
 				 struct sk_buff *skb)
 {
-	switch (inner_mode->encap) {
+	switch (x->props.mode) {
 	case XFRM_MODE_BEET:
 	case XFRM_MODE_TUNNEL:
 		return xfrm_prepare_input(x, skb);
 	case XFRM_MODE_TRANSPORT:
-		if (inner_mode->family == AF_INET)
+		if (x->props.family == AF_INET)
 			return xfrm4_transport_input(x, skb);
-		if (inner_mode->family == AF_INET6)
+		if (x->props.family == AF_INET6)
 			return xfrm6_transport_input(x, skb);
 		break;
 	case XFRM_MODE_ROUTEOPTIMIZATION:
@@ -461,7 +452,6 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 {
 	const struct xfrm_state_afinfo *afinfo;
 	struct net *net = dev_net(skb->dev);
-	const struct xfrm_mode *inner_mode;
 	int err;
 	__be32 seq;
 	__be32 seq_hi;
@@ -491,7 +481,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 			goto drop;
 		}
 
-		family = x->outer_mode.family;
+		family = x->props.family;
 
 		/* An encap_type of -1 indicates async resumption. */
 		if (encap_type == -1) {
@@ -676,17 +666,7 @@ resume:
 
 		XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 
-		inner_mode = &x->inner_mode;
-
-		if (x->sel.family == AF_UNSPEC) {
-			inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
-			if (inner_mode == NULL) {
-				XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
-				goto drop;
-			}
-		}
-
-		if (xfrm_inner_mode_input(x, inner_mode, skb)) {
+		if (xfrm_inner_mode_input(x, skb)) {
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 			goto drop;
 		}
@@ -701,7 +681,7 @@ resume:
 		 * transport mode so the outer address is identical.
 		 */
 		daddr = &x->id.daddr;
-		family = x->outer_mode.family;
+		family = x->props.family;
 
 		err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
 		if (err < 0) {
@@ -732,7 +712,7 @@ resume:
 
 		err = -EAFNOSUPPORT;
 		rcu_read_lock();
-		afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
+		afinfo = xfrm_state_afinfo_get_rcu(x->props.family);
 		if (likely(afinfo))
 			err = afinfo->transport_finish(skb, xfrm_gro || async);
 		rcu_read_unlock();
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index ff114d68cc43..369e5de8558f 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -412,7 +412,7 @@ static int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
 	IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE;
 	skb->protocol = htons(ETH_P_IP);
 
-	switch (x->outer_mode.encap) {
+	switch (x->props.mode) {
 	case XFRM_MODE_BEET:
 		return xfrm4_beet_encap_add(x, skb);
 	case XFRM_MODE_TUNNEL:
@@ -435,7 +435,7 @@ static int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
 	skb->ignore_df = 1;
 	skb->protocol = htons(ETH_P_IPV6);
 
-	switch (x->outer_mode.encap) {
+	switch (x->props.mode) {
 	case XFRM_MODE_BEET:
 		return xfrm6_beet_encap_add(x, skb);
 	case XFRM_MODE_TUNNEL:
@@ -451,22 +451,22 @@ static int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
 
 static int xfrm_outer_mode_output(struct xfrm_state *x, struct sk_buff *skb)
 {
-	switch (x->outer_mode.encap) {
+	switch (x->props.mode) {
 	case XFRM_MODE_BEET:
 	case XFRM_MODE_TUNNEL:
-		if (x->outer_mode.family == AF_INET)
+		if (x->props.family == AF_INET)
 			return xfrm4_prepare_output(x, skb);
-		if (x->outer_mode.family == AF_INET6)
+		if (x->props.family == AF_INET6)
 			return xfrm6_prepare_output(x, skb);
 		break;
 	case XFRM_MODE_TRANSPORT:
-		if (x->outer_mode.family == AF_INET)
+		if (x->props.family == AF_INET)
 			return xfrm4_transport_output(x, skb);
-		if (x->outer_mode.family == AF_INET6)
+		if (x->props.family == AF_INET6)
 			return xfrm6_transport_output(x, skb);
 		break;
 	case XFRM_MODE_ROUTEOPTIMIZATION:
-		if (x->outer_mode.family == AF_INET6)
+		if (x->props.family == AF_INET6)
 			return xfrm6_ro_output(x, skb);
 		WARN_ON_ONCE(1);
 		break;
@@ -875,21 +875,10 @@ static int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb)
 
 static int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb)
 {
-	const struct xfrm_mode *inner_mode;
-
-	if (x->sel.family == AF_UNSPEC)
-		inner_mode = xfrm_ip2inner_mode(x,
-				xfrm_af2proto(skb_dst(skb)->ops->family));
-	else
-		inner_mode = &x->inner_mode;
-
-	if (inner_mode == NULL)
-		return -EAFNOSUPPORT;
-
-	switch (inner_mode->family) {
-	case AF_INET:
+	switch (skb->protocol) {
+	case htons(ETH_P_IP):
 		return xfrm4_extract_output(x, skb);
-	case AF_INET6:
+	case htons(ETH_P_IPV6):
 		return xfrm6_extract_output(x, skb);
 	}