ila: Add struct definitions and helpers

Add structures for identifiers, locators, and an ila address which
is composed of a locator and identifier and in6_addr can be cast to
it. This includes a three bit type field and enums for the types defined
in ILA I-D.

In ILA lwt don't allow user to set a translation for a non-ILA
address (type of identifier is zero meaning it is an IID). This also
requires that the destination prefix is at least 65 bytes (64
bit locator and first byte of identifier).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 64 insertions, 3 deletions

diff --git a/net/ipv6/ila/ila.h b/net/ipv6/ila/ila.h
index 28542cb2b387..f532967d9ed7 100644
--- a/net/ipv6/ila/ila.h
+++ b/net/ipv6/ila/ila.h
@@ -23,9 +23,70 @@
 #include <net/protocol.h>
 #include <uapi/linux/ila.h>
 
+struct ila_locator {
+	union {
+		__u8            v8[8];
+		__be16          v16[4];
+		__be32          v32[2];
+		__be64		v64;
+	};
+};
+
+struct ila_identifier {
+	union {
+		struct {
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+			u8 __space:5;
+			u8 type:3;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+			u8 type:3;
+			u8 __space:5;
+#else
+#error  "Adjust your <asm/byteorder.h> defines"
+#endif
+			u8 __space2[7];
+		};
+		__u8            v8[8];
+		__be16          v16[4];
+		__be32          v32[2];
+		__be64		v64;
+	};
+};
+
+enum {
+	ILA_ATYPE_IID = 0,
+	ILA_ATYPE_LUID,
+	ILA_ATYPE_VIRT_V4,
+	ILA_ATYPE_VIRT_UNI_V6,
+	ILA_ATYPE_VIRT_MULTI_V6,
+	ILA_ATYPE_RSVD_1,
+	ILA_ATYPE_RSVD_2,
+	ILA_ATYPE_RSVD_3,
+};
+
+struct ila_addr {
+	union {
+		struct in6_addr addr;
+		struct {
+			struct ila_locator loc;
+			struct ila_identifier ident;
+		};
+	};
+};
+
+static inline struct ila_addr *ila_a2i(struct in6_addr *addr)
+{
+	return (struct ila_addr *)addr;
+}
+
+static inline bool ila_addr_is_ila(struct ila_addr *iaddr)
+{
+	return (iaddr->ident.type != ILA_ATYPE_IID);
+}
+
 struct ila_params {
-	__be64 locator;
-	__be64 locator_match;
+	struct ila_locator locator;
+	struct ila_locator locator_match;
 	__wsum csum_diff;
 };
 
@@ -38,7 +99,7 @@ static inline __wsum compute_csum_diff8(const __be32 *from, const __be32 *to)
 	return csum_partial(diff, sizeof(diff), 0);
 }
 
-void update_ipv6_locator(struct sk_buff *skb, struct ila_params *p);
+void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p);
 
 int ila_lwt_init(void);
 void ila_lwt_fini(void);