diff options
| -rw-r--r-- | crypto/asymmetric_keys/restrict.c | 38 | ||||
| -rw-r--r-- | include/crypto/public_key.h | 15 |
2 files changed, 53 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/restrict.c b/crypto/asymmetric_keys/restrict.c index 6b1ac5f5896a..48457c6f33f9 100644 --- a/crypto/asymmetric_keys/restrict.c +++ b/crypto/asymmetric_keys/restrict.c @@ -108,6 +108,44 @@ int restrict_link_by_signature(struct key *dest_keyring, return ret; } +/** + * restrict_link_by_ca - Restrict additions to a ring of CA keys + * @dest_keyring: Keyring being linked to. + * @type: The type of key being added. + * @payload: The payload of the new key. + * @trust_keyring: Unused. + * + * Check if the new certificate is a CA. If it is a CA, then mark the new + * certificate as being ok to link. + * + * Returns 0 if the new certificate was accepted, -ENOKEY if the + * certificate is not a CA. -ENOPKG if the signature uses unsupported + * crypto, or some other error if there is a matching certificate but + * the signature check cannot be performed. + */ +int restrict_link_by_ca(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring) +{ + const struct public_key *pkey; + + if (type != &key_type_asymmetric) + return -EOPNOTSUPP; + + pkey = payload->data[asym_crypto]; + if (!pkey) + return -ENOPKG; + if (!test_bit(KEY_EFLAG_CA, &pkey->key_eflags)) + return -ENOKEY; + if (!test_bit(KEY_EFLAG_KEYCERTSIGN, &pkey->key_eflags)) + return -ENOKEY; + if (test_bit(KEY_EFLAG_DIGITALSIG, &pkey->key_eflags)) + return -ENOKEY; + + return 0; +} + static bool match_either_id(const struct asymmetric_key_id **pair, const struct asymmetric_key_id *single) { diff --git a/include/crypto/public_key.h b/include/crypto/public_key.h index 03c3fb990d59..653992a6e941 100644 --- a/include/crypto/public_key.h +++ b/include/crypto/public_key.h @@ -75,6 +75,21 @@ extern int restrict_link_by_key_or_keyring_chain(struct key *trust_keyring, const union key_payload *payload, struct key *trusted); +#if IS_REACHABLE(CONFIG_ASYMMETRIC_KEY_TYPE) +extern int restrict_link_by_ca(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring); +#else +static inline int restrict_link_by_ca(struct key *dest_keyring, + const struct key_type *type, + const union key_payload *payload, + struct key *trust_keyring) +{ + return 0; +} +#endif + extern int query_asymmetric_key(const struct kernel_pkey_params *, struct kernel_pkey_query *); |