Merge tag 'keys-pkcs7-20140708' into keys-next

Here's a set of changes that implement a PKCS#7 message parser in the kernel.

The PKCS#7 message parsing will then be used to limit kexec to authenticated
kernels only if so configured.

The changes provide the following facilities:

 (1) Parse an ASN.1 PKCS#7 message and pick out useful bits such as the data
     content and the X.509 certificates used to sign it and all the data
     signatures.

 (2) Verify all the data signatures against the set of X.509 certificates
     available in the message.

 (3) Follow the certificate chains and verify that:

     (a) for every self-signed X.509 certificate, check that it validly signed
     	 itself, and:

     (b) for every non-self-signed certificate, if we have a 'parent'
     	 certificate, the former is validly signed by the latter.

 (4) Look for intersections between the certificate chains and the trusted
     keyring, if any intersections are found, verify that the trusted
     certificates signed the intersection point in the chain.

 (5) For testing purposes, a key type can be made available that will take a
     PKCS#7 message, check that the message is trustworthy, and if so, add its
     data content into the key.

Note that (5) has to be altered to take account of the preparsing patches
already committed to this branch.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/crypto/asymmetric_keys/x509_parser.h b/crypto/asymmetric_keys/x509_parser.h
index 87d9cc26..1b76f207 100644
--- a/crypto/asymmetric_keys/x509_parser.h
+++ b/crypto/asymmetric_keys/x509_parser.h
@@ -14,7 +14,9 @@
 
 struct x509_certificate {
 	struct x509_certificate *next;
+	struct x509_certificate *signer;	/* Certificate that signed this one */
 	struct public_key *pub;			/* Public key details */
+	struct public_key_signature sig;	/* Signature parameters */
 	char		*issuer;		/* Name of certificate issuer */
 	char		*subject;		/* Name of certificate subject */
 	char		*fingerprint;		/* Key fingerprint as hex */
@@ -25,7 +27,16 @@ struct x509_certificate {
 	unsigned	tbs_size;		/* Size of signed data */
 	unsigned	raw_sig_size;		/* Size of sigature */
 	const void	*raw_sig;		/* Signature data */
-	struct public_key_signature sig;	/* Signature parameters */
+	const void	*raw_serial;		/* Raw serial number in ASN.1 */
+	unsigned	raw_serial_size;
+	unsigned	raw_issuer_size;
+	const void	*raw_issuer;		/* Raw issuer name in ASN.1 */
+	const void	*raw_subject;		/* Raw subject name in ASN.1 */
+	unsigned	raw_subject_size;
+	unsigned	index;
+	bool		seen;			/* Infinite recursion prevention */
+	bool		verified;
+	bool		trusted;
 };
 
 /*