diff options
| -rw-r--r-- | crypto/asymmetric_keys/asymmetric_keys.h | 4 | ||||
| -rw-r--r-- | crypto/asymmetric_keys/asymmetric_type.c | 89 | ||||
| -rw-r--r-- | include/keys/asymmetric-type.h | 38 |
3 files changed, 131 insertions, 0 deletions
diff --git a/crypto/asymmetric_keys/asymmetric_keys.h b/crypto/asymmetric_keys/asymmetric_keys.h index a63c551c6557..917be6b985e7 100644 --- a/crypto/asymmetric_keys/asymmetric_keys.h +++ b/crypto/asymmetric_keys/asymmetric_keys.h @@ -10,6 +10,10 @@ */ int asymmetric_keyid_match(const char *kid, const char *id); +extern bool asymmetric_match_key_ids(const struct asymmetric_key_ids *kids, + const struct asymmetric_key_id *match_id); + +extern struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id); static inline const char *asymmetric_key_id(const struct key *key) { diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c index 7755f918e8d9..92bfc438dd1d 100644 --- a/crypto/asymmetric_keys/asymmetric_type.c +++ b/crypto/asymmetric_keys/asymmetric_type.c @@ -15,6 +15,7 @@ #include <linux/seq_file.h> #include <linux/module.h> #include <linux/slab.h> +#include <linux/ctype.h> #include "asymmetric_keys.h" MODULE_LICENSE("GPL"); @@ -22,6 +23,94 @@ MODULE_LICENSE("GPL"); static LIST_HEAD(asymmetric_key_parsers); static DECLARE_RWSEM(asymmetric_key_parsers_sem); +/** + * asymmetric_key_generate_id: Construct an asymmetric key ID + * @val_1: First binary blob + * @len_1: Length of first binary blob + * @val_2: Second binary blob + * @len_2: Length of second binary blob + * + * Construct an asymmetric key ID from a pair of binary blobs. + */ +struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1, + size_t len_1, + const void *val_2, + size_t len_2) +{ + struct asymmetric_key_id *kid; + + kid = kmalloc(sizeof(struct asymmetric_key_id) + len_1 + len_2, + GFP_KERNEL); + if (!kid) + return ERR_PTR(-ENOMEM); + kid->len = len_1 + len_2; + memcpy(kid->data, val_1, len_1); + memcpy(kid->data + len_1, val_2, len_2); + return kid; +} +EXPORT_SYMBOL_GPL(asymmetric_key_generate_id); + +/** + * asymmetric_key_id_same - Return true if two asymmetric keys IDs are the same. + * @kid_1, @kid_2: The key IDs to compare + */ +bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1, + const struct asymmetric_key_id *kid2) +{ + if (!kid1 || !kid2) + return false; + if (kid1->len != kid2->len) + return false; + return memcmp(kid1->data, kid2->data, kid1->len) == 0; +} +EXPORT_SYMBOL_GPL(asymmetric_key_id_same); + +/** + * asymmetric_match_key_ids - Search asymmetric key IDs + * @kids: The list of key IDs to check + * @match_id: The key ID we're looking for + */ +bool asymmetric_match_key_ids(const struct asymmetric_key_ids *kids, + const struct asymmetric_key_id *match_id) +{ + if (!kids || !match_id) + return false; + if (asymmetric_key_id_same(kids->id[0], match_id)) + return true; + if (asymmetric_key_id_same(kids->id[1], match_id)) + return true; + return false; +} +EXPORT_SYMBOL_GPL(asymmetric_match_key_ids); + +/** + * asymmetric_key_hex_to_key_id - Convert a hex string into a key ID. + * @id: The ID as a hex string. + */ +struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id) +{ + struct asymmetric_key_id *match_id; + const char *p; + ptrdiff_t hexlen; + + if (!*id) + return ERR_PTR(-EINVAL); + for (p = id; *p; p++) + if (!isxdigit(*p)) + return ERR_PTR(-EINVAL); + hexlen = p - id; + if (hexlen & 1) + return ERR_PTR(-EINVAL); + + match_id = kmalloc(sizeof(struct asymmetric_key_id) + hexlen / 2, + GFP_KERNEL); + if (!match_id) + return ERR_PTR(-ENOMEM); + match_id->len = hexlen / 2; + (void)hex2bin(match_id->data, id, hexlen / 2); + return match_id; +} + /* * Match asymmetric key id with partial match * @id: key id to match in a form "id:<id>" diff --git a/include/keys/asymmetric-type.h b/include/keys/asymmetric-type.h index 7dd473496180..044ab0d3aa45 100644 --- a/include/keys/asymmetric-type.h +++ b/include/keys/asymmetric-type.h @@ -19,6 +19,44 @@ extern struct key_type key_type_asymmetric; /* + * Identifiers for an asymmetric key ID. We have three ways of looking up a + * key derived from an X.509 certificate: + * + * (1) Serial Number & Issuer. Non-optional. This is the only valid way to + * map a PKCS#7 signature to an X.509 certificate. + * + * (2) Issuer & Subject Unique IDs. Optional. These were the original way to + * match X.509 certificates, but have fallen into disuse in favour of (3). + * + * (3) Auth & Subject Key Identifiers. Optional. SKIDs are only provided on + * CA keys that are intended to sign other keys, so don't appear in end + * user certificates unless forced. + * + * We could also support an PGP key identifier, which is just a SHA1 sum of the + * public key and certain parameters, but since we don't support PGP keys at + * the moment, we shall ignore those. + * + * What we actually do is provide a place where binary identifiers can be + * stashed and then compare against them when checking for an id match. + */ +struct asymmetric_key_id { + unsigned short len; + unsigned char data[]; +}; + +struct asymmetric_key_ids { + void *id[2]; +}; + +extern bool asymmetric_key_id_same(const struct asymmetric_key_id *kid1, + const struct asymmetric_key_id *kid2); + +extern struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1, + size_t len_1, + const void *val_2, + size_t len_2); + +/* * The payload is at the discretion of the subtype. */ |