| 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| 2 | /* |
| 3 | * Public Key Signature Algorithm |
| 4 | * |
| 5 | * Copyright (c) 2023 Herbert Xu <herbert@gondor.apana.org.au> |
| 6 | */ |
| 7 | #ifndef _CRYPTO_SIG_H |
| 8 | #define _CRYPTO_SIG_H |
| 9 | |
| 10 | #include <linux/crypto.h> |
| 11 | |
| 12 | /** |
| 13 | * struct crypto_sig - user-instantiated objects which encapsulate |
| 14 | * algorithms and core processing logic |
| 15 | * |
| 16 | * @base: Common crypto API algorithm data structure |
| 17 | */ |
| 18 | struct crypto_sig { |
| 19 | struct crypto_tfm base; |
| 20 | }; |
| 21 | |
| 22 | /** |
| 23 | * struct sig_alg - generic public key signature algorithm |
| 24 | * |
| 25 | * @sign: Function performs a sign operation as defined by public key |
| 26 | * algorithm. On success, the signature size is returned. |
| 27 | * Optional. |
| 28 | * @verify: Function performs a complete verify operation as defined by |
| 29 | * public key algorithm, returning verification status. Optional. |
| 30 | * @set_pub_key: Function invokes the algorithm specific set public key |
| 31 | * function, which knows how to decode and interpret |
| 32 | * the BER encoded public key and parameters. Mandatory. |
| 33 | * @set_priv_key: Function invokes the algorithm specific set private key |
| 34 | * function, which knows how to decode and interpret |
| 35 | * the BER encoded private key and parameters. Optional. |
| 36 | * @key_size: Function returns key size. Mandatory. |
| 37 | * @digest_size: Function returns maximum digest size. Optional. |
| 38 | * @max_size: Function returns maximum signature size. Optional. |
| 39 | * @init: Initialize the cryptographic transformation object. |
| 40 | * This function is used to initialize the cryptographic |
| 41 | * transformation object. This function is called only once at |
| 42 | * the instantiation time, right after the transformation context |
| 43 | * was allocated. In case the cryptographic hardware has some |
| 44 | * special requirements which need to be handled by software, this |
| 45 | * function shall check for the precise requirement of the |
| 46 | * transformation and put any software fallbacks in place. |
| 47 | * @exit: Deinitialize the cryptographic transformation object. This is a |
| 48 | * counterpart to @init, used to remove various changes set in |
| 49 | * @init. |
| 50 | * |
| 51 | * @base: Common crypto API algorithm data structure |
| 52 | */ |
| 53 | struct sig_alg { |
| 54 | int (*sign)(struct crypto_sig *tfm, |
| 55 | const void *src, unsigned int slen, |
| 56 | void *dst, unsigned int dlen); |
| 57 | int (*verify)(struct crypto_sig *tfm, |
| 58 | const void *src, unsigned int slen, |
| 59 | const void *digest, unsigned int dlen); |
| 60 | int (*set_pub_key)(struct crypto_sig *tfm, |
| 61 | const void *key, unsigned int keylen); |
| 62 | int (*set_priv_key)(struct crypto_sig *tfm, |
| 63 | const void *key, unsigned int keylen); |
| 64 | unsigned int (*key_size)(struct crypto_sig *tfm); |
| 65 | unsigned int (*digest_size)(struct crypto_sig *tfm); |
| 66 | unsigned int (*max_size)(struct crypto_sig *tfm); |
| 67 | int (*init)(struct crypto_sig *tfm); |
| 68 | void (*exit)(struct crypto_sig *tfm); |
| 69 | |
| 70 | struct crypto_alg base; |
| 71 | }; |
| 72 | |
| 73 | /** |
| 74 | * DOC: Generic Public Key Signature API |
| 75 | * |
| 76 | * The Public Key Signature API is used with the algorithms of type |
| 77 | * CRYPTO_ALG_TYPE_SIG (listed as type "sig" in /proc/crypto) |
| 78 | */ |
| 79 | |
| 80 | /** |
| 81 | * crypto_alloc_sig() - allocate signature tfm handle |
| 82 | * @alg_name: is the cra_name / name or cra_driver_name / driver name of the |
| 83 | * signing algorithm e.g. "ecdsa" |
| 84 | * @type: specifies the type of the algorithm |
| 85 | * @mask: specifies the mask for the algorithm |
| 86 | * |
| 87 | * Allocate a handle for public key signature algorithm. The returned struct |
| 88 | * crypto_sig is the handle that is required for any subsequent |
| 89 | * API invocation for signature operations. |
| 90 | * |
| 91 | * Return: allocated handle in case of success; IS_ERR() is true in case |
| 92 | * of an error, PTR_ERR() returns the error code. |
| 93 | */ |
| 94 | struct crypto_sig *crypto_alloc_sig(const char *alg_name, u32 type, u32 mask); |
| 95 | |
| 96 | static inline struct crypto_tfm *crypto_sig_tfm(struct crypto_sig *tfm) |
| 97 | { |
| 98 | return &tfm->base; |
| 99 | } |
| 100 | |
| 101 | static inline struct crypto_sig *__crypto_sig_tfm(struct crypto_tfm *tfm) |
| 102 | { |
| 103 | return container_of(tfm, struct crypto_sig, base); |
| 104 | } |
| 105 | |
| 106 | static inline struct sig_alg *__crypto_sig_alg(struct crypto_alg *alg) |
| 107 | { |
| 108 | return container_of(alg, struct sig_alg, base); |
| 109 | } |
| 110 | |
| 111 | static inline struct sig_alg *crypto_sig_alg(struct crypto_sig *tfm) |
| 112 | { |
| 113 | return __crypto_sig_alg(alg: crypto_sig_tfm(tfm)->__crt_alg); |
| 114 | } |
| 115 | |
| 116 | /** |
| 117 | * crypto_free_sig() - free signature tfm handle |
| 118 | * |
| 119 | * @tfm: signature tfm handle allocated with crypto_alloc_sig() |
| 120 | * |
| 121 | * If @tfm is a NULL or error pointer, this function does nothing. |
| 122 | */ |
| 123 | static inline void crypto_free_sig(struct crypto_sig *tfm) |
| 124 | { |
| 125 | crypto_destroy_tfm(mem: tfm, tfm: crypto_sig_tfm(tfm)); |
| 126 | } |
| 127 | |
| 128 | /** |
| 129 | * crypto_sig_keysize() - Get key size |
| 130 | * |
| 131 | * Function returns the key size in bits. |
| 132 | * Function assumes that the key is already set in the transformation. If this |
| 133 | * function is called without a setkey or with a failed setkey, you may end up |
| 134 | * in a NULL dereference. |
| 135 | * |
| 136 | * @tfm: signature tfm handle allocated with crypto_alloc_sig() |
| 137 | */ |
| 138 | static inline unsigned int crypto_sig_keysize(struct crypto_sig *tfm) |
| 139 | { |
| 140 | struct sig_alg *alg = crypto_sig_alg(tfm); |
| 141 | |
| 142 | return alg->key_size(tfm); |
| 143 | } |
| 144 | |
| 145 | /** |
| 146 | * crypto_sig_digestsize() - Get maximum digest size |
| 147 | * |
| 148 | * Function returns the maximum digest size in bytes. |
| 149 | * Function assumes that the key is already set in the transformation. If this |
| 150 | * function is called without a setkey or with a failed setkey, you may end up |
| 151 | * in a NULL dereference. |
| 152 | * |
| 153 | * @tfm: signature tfm handle allocated with crypto_alloc_sig() |
| 154 | */ |
| 155 | static inline unsigned int crypto_sig_digestsize(struct crypto_sig *tfm) |
| 156 | { |
| 157 | struct sig_alg *alg = crypto_sig_alg(tfm); |
| 158 | |
| 159 | return alg->digest_size(tfm); |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * crypto_sig_maxsize() - Get maximum signature size |
| 164 | * |
| 165 | * Function returns the maximum signature size in bytes. |
| 166 | * Function assumes that the key is already set in the transformation. If this |
| 167 | * function is called without a setkey or with a failed setkey, you may end up |
| 168 | * in a NULL dereference. |
| 169 | * |
| 170 | * @tfm: signature tfm handle allocated with crypto_alloc_sig() |
| 171 | */ |
| 172 | static inline unsigned int crypto_sig_maxsize(struct crypto_sig *tfm) |
| 173 | { |
| 174 | struct sig_alg *alg = crypto_sig_alg(tfm); |
| 175 | |
| 176 | return alg->max_size(tfm); |
| 177 | } |
| 178 | |
| 179 | /** |
| 180 | * crypto_sig_sign() - Invoke signing operation |
| 181 | * |
| 182 | * Function invokes the specific signing operation for a given algorithm |
| 183 | * |
| 184 | * @tfm: signature tfm handle allocated with crypto_alloc_sig() |
| 185 | * @src: source buffer |
| 186 | * @slen: source length |
| 187 | * @dst: destination obuffer |
| 188 | * @dlen: destination length |
| 189 | * |
| 190 | * Return: signature size on success; error code in case of error |
| 191 | */ |
| 192 | static inline int crypto_sig_sign(struct crypto_sig *tfm, |
| 193 | const void *src, unsigned int slen, |
| 194 | void *dst, unsigned int dlen) |
| 195 | { |
| 196 | struct sig_alg *alg = crypto_sig_alg(tfm); |
| 197 | |
| 198 | return alg->sign(tfm, src, slen, dst, dlen); |
| 199 | } |
| 200 | |
| 201 | /** |
| 202 | * crypto_sig_verify() - Invoke signature verification |
| 203 | * |
| 204 | * Function invokes the specific signature verification operation |
| 205 | * for a given algorithm. |
| 206 | * |
| 207 | * @tfm: signature tfm handle allocated with crypto_alloc_sig() |
| 208 | * @src: source buffer |
| 209 | * @slen: source length |
| 210 | * @digest: digest |
| 211 | * @dlen: digest length |
| 212 | * |
| 213 | * Return: zero on verification success; error code in case of error. |
| 214 | */ |
| 215 | static inline int crypto_sig_verify(struct crypto_sig *tfm, |
| 216 | const void *src, unsigned int slen, |
| 217 | const void *digest, unsigned int dlen) |
| 218 | { |
| 219 | struct sig_alg *alg = crypto_sig_alg(tfm); |
| 220 | |
| 221 | return alg->verify(tfm, src, slen, digest, dlen); |
| 222 | } |
| 223 | |
| 224 | /** |
| 225 | * crypto_sig_set_pubkey() - Invoke set public key operation |
| 226 | * |
| 227 | * Function invokes the algorithm specific set key function, which knows |
| 228 | * how to decode and interpret the encoded key and parameters |
| 229 | * |
| 230 | * @tfm: tfm handle |
| 231 | * @key: BER encoded public key, algo OID, paramlen, BER encoded |
| 232 | * parameters |
| 233 | * @keylen: length of the key (not including other data) |
| 234 | * |
| 235 | * Return: zero on success; error code in case of error |
| 236 | */ |
| 237 | static inline int crypto_sig_set_pubkey(struct crypto_sig *tfm, |
| 238 | const void *key, unsigned int keylen) |
| 239 | { |
| 240 | struct sig_alg *alg = crypto_sig_alg(tfm); |
| 241 | |
| 242 | return alg->set_pub_key(tfm, key, keylen); |
| 243 | } |
| 244 | |
| 245 | /** |
| 246 | * crypto_sig_set_privkey() - Invoke set private key operation |
| 247 | * |
| 248 | * Function invokes the algorithm specific set key function, which knows |
| 249 | * how to decode and interpret the encoded key and parameters |
| 250 | * |
| 251 | * @tfm: tfm handle |
| 252 | * @key: BER encoded private key, algo OID, paramlen, BER encoded |
| 253 | * parameters |
| 254 | * @keylen: length of the key (not including other data) |
| 255 | * |
| 256 | * Return: zero on success; error code in case of error |
| 257 | */ |
| 258 | static inline int crypto_sig_set_privkey(struct crypto_sig *tfm, |
| 259 | const void *key, unsigned int keylen) |
| 260 | { |
| 261 | struct sig_alg *alg = crypto_sig_alg(tfm); |
| 262 | |
| 263 | return alg->set_priv_key(tfm, key, keylen); |
| 264 | } |
| 265 | #endif |
| 266 | |