[XFRM]: Add XFRM_MODE_xxx for future use.

Transformation mode is used as either IPsec transport or tunnel.
It is required to add two more items, route optimization and inbound trigger
for Mobile IPv6.
Based on MIPL2 kernel patch.

This patch was also written by: Ville Nuorvala <vnuorval@tcs.hut.fi>

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 00ffa7b..60954fc 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -398,7 +398,7 @@
 		goto error;
 	
 	x->props.header_len = XFRM_ALIGN8(sizeof(struct ipv6_auth_hdr) + ahp->icv_trunc_len);
-	if (x->props.mode)
+	if (x->props.mode == XFRM_MODE_TUNNEL)
 		x->props.header_len += sizeof(struct ipv6hdr);
 	x->data = ahp;
 
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 2ebfd28..2b8e52e 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -237,7 +237,7 @@
 	struct esp_data *esp = x->data;
 	u32 blksize = ALIGN(crypto_blkcipher_blocksize(esp->conf.tfm), 4);
 
-	if (x->props.mode) {
+	if (x->props.mode == XFRM_MODE_TUNNEL) {
 		mtu = ALIGN(mtu + 2, blksize);
 	} else {
 		/* The worst case. */
@@ -358,7 +358,7 @@
 	if (crypto_blkcipher_setkey(tfm, esp->conf.key, esp->conf.key_len))
 		goto error;
 	x->props.header_len = sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen;
-	if (x->props.mode)
+	if (x->props.mode == XFRM_MODE_TUNNEL)
 		x->props.header_len += sizeof(struct ipv6hdr);
 	x->data = esp;
 	return 0;
diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c
index a81e9e9..19eba8d 100644
--- a/net/ipv6/ipcomp6.c
+++ b/net/ipv6/ipcomp6.c
@@ -212,7 +212,7 @@
 	memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr));
 	memcpy(&t->sel, &x->sel, sizeof(t->sel));
 	t->props.family = AF_INET6;
-	t->props.mode = 1;
+	t->props.mode = XFRM_MODE_TUNNEL;
 	memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr));
 
 	if (xfrm_init_state(t))
@@ -417,7 +417,7 @@
 		goto out;
 
 	x->props.header_len = 0;
-	if (x->props.mode)
+	if (x->props.mode == XFRM_MODE_TUNNEL)
 		x->props.header_len += sizeof(struct ipv6hdr);
 	
 	mutex_lock(&ipcomp6_resource_mutex);
@@ -429,7 +429,7 @@
 		goto error;
 	mutex_unlock(&ipcomp6_resource_mutex);
 
-	if (x->props.mode) {
+	if (x->props.mode == XFRM_MODE_TUNNEL) {
 		err = ipcomp6_tunnel_attach(x);
 		if (err)
 			goto error_tunnel;
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 0405d74..ee2f6b3 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -72,7 +72,7 @@
 		if (x->mode->input(x, skb))
 			goto drop;
 
-		if (x->props.mode) { /* XXX */
+		if (x->props.mode == XFRM_MODE_TUNNEL) { /* XXX */
 			decaps = 1;
 			break;
 		}
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index 6d11174..26f1886 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -47,7 +47,7 @@
 			goto error_nolock;
 	}
 
-	if (x->props.mode) {
+	if (x->props.mode == XFRM_MODE_TUNNEL) {
 		err = xfrm6_tunnel_check_size(skb);
 		if (err)
 			goto error_nolock;
@@ -80,7 +80,7 @@
 		}
 		dst = skb->dst;
 		x = dst->xfrm;
-	} while (x && !x->props.mode);
+	} while (x && (x->props.mode != XFRM_MODE_TUNNEL));
 
 	IP6CB(skb)->flags |= IP6SKB_XFRM_TRANSFORMED;
 	err = 0;
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index 73cd250..81355bb 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -114,7 +114,7 @@
 
 		dst1->next = dst_prev;
 		dst_prev = dst1;
-		if (xfrm[i]->props.mode) {
+		if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
 			remote = (struct in6_addr*)&xfrm[i]->id.daddr;
 			local  = (struct in6_addr*)&xfrm[i]->props.saddr;
 			tunnel = 1;
diff --git a/net/ipv6/xfrm6_state.c b/net/ipv6/xfrm6_state.c
index b33296b..a1a1f54 100644
--- a/net/ipv6/xfrm6_state.c
+++ b/net/ipv6/xfrm6_state.c
@@ -42,7 +42,7 @@
 	memcpy(&x->props.saddr, &tmpl->saddr, sizeof(x->props.saddr));
 	if (ipv6_addr_any((struct in6_addr*)&x->props.saddr))
 		memcpy(&x->props.saddr, saddr, sizeof(x->props.saddr));
-	if (tmpl->mode && ipv6_addr_any((struct in6_addr*)&x->props.saddr)) {
+	if (tmpl->mode == XFRM_MODE_TUNNEL && ipv6_addr_any((struct in6_addr*)&x->props.saddr)) {
 		struct rt6_info *rt;
 		struct flowi fl_tunnel = {
 			.nl_u = {
diff --git a/net/ipv6/xfrm6_tunnel.c b/net/ipv6/xfrm6_tunnel.c
index c8f9369..59685ee 100644
--- a/net/ipv6/xfrm6_tunnel.c
+++ b/net/ipv6/xfrm6_tunnel.c
@@ -307,7 +307,7 @@
 
 static int xfrm6_tunnel_init_state(struct xfrm_state *x)
 {
-	if (!x->props.mode)
+	if (x->props.mode != XFRM_MODE_TUNNEL)
 		return -EINVAL;
 
 	if (x->encap)