1 /* Asymmetric public-key algorithm definitions 2 * 3 * See Documentation/crypto/asymmetric-keys.txt 4 * 5 * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved. 6 * Written by David Howells (dhowells@redhat.com) 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public Licence 10 * as published by the Free Software Foundation; either version 11 * 2 of the Licence, or (at your option) any later version. 12 */ 13 14 #ifndef _LINUX_PUBLIC_KEY_H 15 #define _LINUX_PUBLIC_KEY_H 16 17 #include <linux/mpi.h> 18 #include <crypto/hash_info.h> 19 20 enum pkey_algo { 21 PKEY_ALGO_DSA, 22 PKEY_ALGO_RSA, 23 PKEY_ALGO__LAST 24 }; 25 26 extern const char *const pkey_algo_name[PKEY_ALGO__LAST]; 27 extern const struct public_key_algorithm *pkey_algo[PKEY_ALGO__LAST]; 28 29 /* asymmetric key implementation supports only up to SHA224 */ 30 #define PKEY_HASH__LAST (HASH_ALGO_SHA224 + 1) 31 32 enum pkey_id_type { 33 PKEY_ID_PGP, /* OpenPGP generated key ID */ 34 PKEY_ID_X509, /* X.509 arbitrary subjectKeyIdentifier */ 35 PKEY_ID_PKCS7, /* Signature in PKCS#7 message */ 36 PKEY_ID_TYPE__LAST 37 }; 38 39 extern const char *const pkey_id_type_name[PKEY_ID_TYPE__LAST]; 40 41 /* 42 * The use to which an asymmetric key is being put. 43 */ 44 enum key_being_used_for { 45 VERIFYING_MODULE_SIGNATURE, 46 VERIFYING_FIRMWARE_SIGNATURE, 47 VERIFYING_KEXEC_PE_SIGNATURE, 48 VERIFYING_KEY_SIGNATURE, 49 VERIFYING_KEY_SELF_SIGNATURE, 50 VERIFYING_UNSPECIFIED_SIGNATURE, 51 NR__KEY_BEING_USED_FOR 52 }; 53 extern const char *const key_being_used_for[NR__KEY_BEING_USED_FOR]; 54 55 /* 56 * Cryptographic data for the public-key subtype of the asymmetric key type. 57 * 58 * Note that this may include private part of the key as well as the public 59 * part. 60 */ 61 struct public_key { 62 const struct public_key_algorithm *algo; 63 u8 capabilities; 64 #define PKEY_CAN_ENCRYPT 0x01 65 #define PKEY_CAN_DECRYPT 0x02 66 #define PKEY_CAN_SIGN 0x04 67 #define PKEY_CAN_VERIFY 0x08 68 enum pkey_algo pkey_algo : 8; 69 enum pkey_id_type id_type : 8; 70 union { 71 MPI mpi[5]; 72 struct { 73 MPI p; /* DSA prime */ 74 MPI q; /* DSA group order */ 75 MPI g; /* DSA group generator */ 76 MPI y; /* DSA public-key value = g^x mod p */ 77 MPI x; /* DSA secret exponent (if present) */ 78 } dsa; 79 struct { 80 MPI n; /* RSA public modulus */ 81 MPI e; /* RSA public encryption exponent */ 82 MPI d; /* RSA secret encryption exponent (if present) */ 83 MPI p; /* RSA secret prime (if present) */ 84 MPI q; /* RSA secret prime (if present) */ 85 } rsa; 86 }; 87 }; 88 89 extern void public_key_destroy(void *payload); 90 91 /* 92 * Public key cryptography signature data 93 */ 94 struct public_key_signature { 95 u8 *digest; 96 u8 digest_size; /* Number of bytes in digest */ 97 u8 nr_mpi; /* Occupancy of mpi[] */ 98 enum pkey_algo pkey_algo : 8; 99 enum hash_algo pkey_hash_algo : 8; 100 union { 101 MPI mpi[2]; 102 struct { 103 MPI s; /* m^d mod n */ 104 } rsa; 105 struct { 106 MPI r; 107 MPI s; 108 } dsa; 109 }; 110 }; 111 112 struct key; 113 extern int verify_signature(const struct key *key, 114 const struct public_key_signature *sig); 115 116 struct asymmetric_key_id; 117 extern struct key *x509_request_asymmetric_key(struct key *keyring, 118 const struct asymmetric_key_id *id, 119 const struct asymmetric_key_id *skid, 120 bool partial); 121 122 #endif /* _LINUX_PUBLIC_KEY_H */ 123