[v8,2/8] oid_registry: Add TCG defined OIDS for TPM keys

Commit Message

James Bottomley March 10, 2020, 5:16 a.m. UTC

The TCG has defined an OID prefix "2.23.133.10.1" for the various TPM
key uses.  We've defined three of the available numbers:

2.23.133.10.1.3 TPM Loadable key.  This is an asymmetric key (Usually
		RSA2048 or Elliptic Curve) which can be imported by a
		TPM2_Load() operation.

2.23.133.10.1.4 TPM Importable Key.  This is an asymmetric key (Usually
		RSA2048 or Elliptic Curve) which can be imported by a
		TPM2_Import() operation.

Both loadable and importable keys are specific to a given TPM, the
difference is that a loadable key is wrapped with the symmetric
secret, so must have been created by the TPM itself.  An importable
key is wrapped with a DH shared secret, and may be created without
access to the TPM provided you know the public part of the parent key.

2.23.133.10.1.5 TPM Sealed Data.  This is a set of data (up to 128
		bytes) which is sealed by the TPM.  It usually
		represents a symmetric key and must be unsealed before
		use.

The ASN.1 binary key form starts of with this OID as the first element
of a sequence, giving the binary form a unique recognizable identity
marker regardless of encoding.

Signed-off-by: James Bottomley <[e-mail]>
Acked-by: Jarkko Sakkinen <[e-mail]>

---

v3: correct OID_TPMImportableKey name
v7: add ack
---
 include/linux/oid_registry.h | 5 +++++
 1 file changed, 5 insertions(+)

Comments

David Howells March 19, 2020, 4:48 p.m. UTC | #1

James Bottomley <[e-mail]> wrote:

> The TCG has defined an OID prefix "2.23.133.10.1" for the various TPM
> key uses.  We've defined three of the available numbers:
> 
> 2.23.133.10.1.3 TPM Loadable key.  This is an asymmetric key (Usually
> 		RSA2048 or Elliptic Curve) which can be imported by a
> 		TPM2_Load() operation.
> 
> 2.23.133.10.1.4 TPM Importable Key.  This is an asymmetric key (Usually
> 		RSA2048 or Elliptic Curve) which can be imported by a
> 		TPM2_Import() operation.
> 
> Both loadable and importable keys are specific to a given TPM, the
> difference is that a loadable key is wrapped with the symmetric
> secret, so must have been created by the TPM itself.  An importable
> key is wrapped with a DH shared secret, and may be created without
> access to the TPM provided you know the public part of the parent key.
> 
> 2.23.133.10.1.5 TPM Sealed Data.  This is a set of data (up to 128
> 		bytes) which is sealed by the TPM.  It usually
> 		represents a symmetric key and must be unsealed before
> 		use.
> 
> The ASN.1 binary key form starts of with this OID as the first element
> of a sequence, giving the binary form a unique recognizable identity
> marker regardless of encoding.
> 
> Signed-off-by: James Bottomley <[e-mail]>
> Acked-by: Jarkko Sakkinen <[e-mail]>

Reviewed-by: David Howells <[e-mail]>

Patch

diff --git a/include/linux/oid_registry.h b/include/linux/oid_registry.h
index 657d6bf2c064..f6e2276e5f30 100644
--- a/include/linux/oid_registry.h
+++ b/include/linux/oid_registry.h
@@ -107,6 +107,11 @@  enum OID {
 	OID_gostTC26Sign512B,		/* 1.2.643.7.1.2.1.2.2 */
 	OID_gostTC26Sign512C,		/* 1.2.643.7.1.2.1.2.3 */
 
+	/* TCG defined OIDS for TPM based keys */
+	OID_TPMLoadableKey,		/* 2.23.133.10.1.3 */
+	OID_TPMImportableKey,		/* 2.23.133.10.1.4 */
+	OID_TPMSealedData,		/* 2.23.133.10.1.5 */
+
 	OID__NR
 };