X.509: Implement simple static OID registry

Implement a simple static OID registry that allows the mapping of an encoded
OID to an enum value for ease of use.

The OID registry index enum appears in the:

	linux/oid_registry.h

header file.  A script generates the registry from lines in the header file
that look like:

	<sp*>OID_foo,<sp*>/*<sp*>1.2.3.4<sp*>*/

The actual OID is taken to be represented by the numbers with interpolated
dots in the comment.

All other lines in the header are ignored.

The registry is queries by calling:

	OID look_up_oid(const void *data, size_t datasize);

This returns a number from the registry enum representing the OID if found or
OID__NR if not.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

1 files changed, 5 insertions, 0 deletions

diff --git a/lib/Kconfig b/lib/Kconfig
index bb94c1ba616..4b31a46fb30 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -396,4 +396,9 @@ config SIGNATURE
 config LIBFDT
 	bool
 
+config OID_REGISTRY
+	tristate
+	help
+	  Enable fast lookup object identifier registry.
+
 endmenu