From 46963b774d441c833afc1535f6d84b3df2a94204 Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 16 Sep 2014 17:36:13 +0100 Subject: KEYS: Overhaul key identification when searching for asymmetric keys Make use of the new match string preparsing to overhaul key identification when searching for asymmetric keys. The following changes are made: (1) Use the previously created asymmetric_key_id struct to hold the following key IDs derived from the X.509 certificate or PKCS#7 message: id: serial number + issuer skid: subjKeyId + subject authority: authKeyId + issuer (2) Replace the hex fingerprint attached to key->type_data[1] with an asymmetric_key_ids struct containing the id and the skid (if present). (3) Make the asymmetric_type match data preparse select one of two searches: (a) An iterative search for the key ID given if prefixed with "id:". The prefix is expected to be followed by a hex string giving the ID to search for. The criterion key ID is checked against all key IDs recorded on the key. (b) A direct search if the key ID is not prefixed with "id:". This will look for an exact match on the key description. (4) Make x509_request_asymmetric_key() take a key ID. This is then converted into "id:" and passed into keyring_search() where match preparsing will turn it back into a binary ID. (5) X.509 certificate verification then takes the authority key ID and looks up a key that matches it to find the public key for the certificate signature. (6) PKCS#7 certificate verification then takes the id key ID and looks up a key that matches it to find the public key for the signed information block signature. Additional changes: (1) Multiple subjKeyId and authKeyId values on an X.509 certificate cause the cert to be rejected with -EBADMSG. (2) The 'fingerprint' ID is gone. This was primarily intended to convey PGP public key fingerprints. If PGP is supported in future, this should generate a key ID that carries the fingerprint. (3) Th ca_keyid= kernel command line option is now converted to a key ID and used to match the authority key ID. Possibly this should only match the actual authKeyId part and not the issuer as well. Signed-off-by: David Howells Acked-by: Vivek Goyal --- include/crypto/public_key.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/crypto') diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h index 0d164c6af539..fa73a6fd536c 100644 --- a/include/crypto/public_key.h +++ b/include/crypto/public_key.h @@ -15,6 +15,7 @@ #define _LINUX_PUBLIC_KEY_H #include +#include #include enum pkey_algo { @@ -98,8 +99,8 @@ struct key; extern int verify_signature(const struct key *key, const struct public_key_signature *sig); +struct asymmetric_key_id; extern struct key *x509_request_asymmetric_key(struct key *keyring, - const char *issuer, - const char *key_id); + const struct asymmetric_key_id *kid); #endif /* _LINUX_PUBLIC_KEY_H */ -- cgit v1.2.1