1 /* 2 * Public Key Encryption 3 * 4 * Copyright (c) 2015, Intel Corporation 5 * Authors: Tadeusz Struk <tadeusz.struk@intel.com> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License as published by the Free 9 * Software Foundation; either version 2 of the License, or (at your option) 10 * any later version. 11 * 12 */ 13 #ifndef _CRYPTO_AKCIPHER_H 14 #define _CRYPTO_AKCIPHER_H 15 #include <linux/crypto.h> 16 17 /** 18 * struct akcipher_request - public key request 19 * 20 * @base: Common attributes for async crypto requests 21 * @src: Pointer to memory containing the input parameters 22 * The format of the parameter(s) is expeted to be Octet String 23 * @dst: Pointer to memory whare the result will be stored 24 * @src_len: Size of the input parameter 25 * @dst_len: Size of the output buffer. It needs to be at leaset 26 * as big as the expected result depending on the operation 27 * After operation it will be updated with the acctual size of the 28 * result. In case of error, where the dst_len was insufficient, 29 * it will be updated to the size required for the operation. 30 * @__ctx: Start of private context data 31 */ 32 struct akcipher_request { 33 struct crypto_async_request base; 34 void *src; 35 void *dst; 36 unsigned int src_len; 37 unsigned int dst_len; 38 void *__ctx[] CRYPTO_MINALIGN_ATTR; 39 }; 40 41 /** 42 * struct crypto_akcipher - user-instantiated objects which encapsulate 43 * algorithms and core processing logic 44 * 45 * @base: Common crypto API algorithm data structure 46 */ 47 struct crypto_akcipher { 48 struct crypto_tfm base; 49 }; 50 51 /** 52 * struct akcipher_alg - generic public key algorithm 53 * 54 * @sign: Function performs a sign operation as defined by public key 55 * algorithm. In case of error, where the dst_len was insufficient, 56 * the req->dst_len will be updated to the size required for the 57 * operation 58 * @verify: Function performs a sign operation as defined by public key 59 * algorithm. In case of error, where the dst_len was insufficient, 60 * the req->dst_len will be updated to the size required for the 61 * operation 62 * @encrypt: Function performs an encrytp operation as defined by public key 63 * algorithm. In case of error, where the dst_len was insufficient, 64 * the req->dst_len will be updated to the size required for the 65 * operation 66 * @decrypt: Function performs a decrypt operation as defined by public key 67 * algorithm. In case of error, where the dst_len was insufficient, 68 * the req->dst_len will be updated to the size required for the 69 * operation 70 * @setkey: Function invokes the algorithm specific set key function, which 71 * knows how to decode and interpret the BER encoded key 72 * @init: Initialize the cryptographic transformation object. 73 * This function is used to initialize the cryptographic 74 * transformation object. This function is called only once at 75 * the instantiation time, right after the transformation context 76 * was allocated. In case the cryptographic hardware has some 77 * special requirements which need to be handled by software, this 78 * function shall check for the precise requirement of the 79 * transformation and put any software fallbacks in place. 80 * @exit: Deinitialize the cryptographic transformation object. This is a 81 * counterpart to @init, used to remove various changes set in 82 * @init. 83 * 84 * @reqsize: Request context size required by algorithm implementation 85 * @base: Common crypto API algorithm data structure 86 */ 87 struct akcipher_alg { 88 int (*sign)(struct akcipher_request *req); 89 int (*verify)(struct akcipher_request *req); 90 int (*encrypt)(struct akcipher_request *req); 91 int (*decrypt)(struct akcipher_request *req); 92 int (*setkey)(struct crypto_akcipher *tfm, const void *key, 93 unsigned int keylen); 94 int (*init)(struct crypto_akcipher *tfm); 95 void (*exit)(struct crypto_akcipher *tfm); 96 97 unsigned int reqsize; 98 struct crypto_alg base; 99 }; 100 101 /** 102 * DOC: Generic Public Key API 103 * 104 * The Public Key API is used with the algorithms of type 105 * CRYPTO_ALG_TYPE_AKCIPHER (listed as type "akcipher" in /proc/crypto) 106 */ 107 108 /** 109 * crypto_alloc_akcipher() -- allocate AKCIPHER tfm handle 110 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 111 * public key algorithm e.g. "rsa" 112 * @type: specifies the type of the algorithm 113 * @mask: specifies the mask for the algorithm 114 * 115 * Allocate a handle for public key algorithm. The returned struct 116 * crypto_akcipher is the handle that is required for any subsequent 117 * API invocation for the public key operations. 118 * 119 * Return: allocated handle in case of success; IS_ERR() is true in case 120 * of an error, PTR_ERR() returns the error code. 121 */ 122 struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type, 123 u32 mask); 124 125 static inline struct crypto_tfm *crypto_akcipher_tfm( 126 struct crypto_akcipher *tfm) 127 { 128 return &tfm->base; 129 } 130 131 static inline struct akcipher_alg *__crypto_akcipher_alg(struct crypto_alg *alg) 132 { 133 return container_of(alg, struct akcipher_alg, base); 134 } 135 136 static inline struct crypto_akcipher *__crypto_akcipher_tfm( 137 struct crypto_tfm *tfm) 138 { 139 return container_of(tfm, struct crypto_akcipher, base); 140 } 141 142 static inline struct akcipher_alg *crypto_akcipher_alg( 143 struct crypto_akcipher *tfm) 144 { 145 return __crypto_akcipher_alg(crypto_akcipher_tfm(tfm)->__crt_alg); 146 } 147 148 static inline unsigned int crypto_akcipher_reqsize(struct crypto_akcipher *tfm) 149 { 150 return crypto_akcipher_alg(tfm)->reqsize; 151 } 152 153 static inline void akcipher_request_set_tfm(struct akcipher_request *req, 154 struct crypto_akcipher *tfm) 155 { 156 req->base.tfm = crypto_akcipher_tfm(tfm); 157 } 158 159 static inline struct crypto_akcipher *crypto_akcipher_reqtfm( 160 struct akcipher_request *req) 161 { 162 return __crypto_akcipher_tfm(req->base.tfm); 163 } 164 165 /** 166 * crypto_free_akcipher() -- free AKCIPHER tfm handle 167 * 168 * @tfm: AKCIPHER tfm handle allocated with crypto_alloc_akcipher() 169 */ 170 static inline void crypto_free_akcipher(struct crypto_akcipher *tfm) 171 { 172 crypto_destroy_tfm(tfm, crypto_akcipher_tfm(tfm)); 173 } 174 175 /** 176 * akcipher_request_alloc() -- allocates public key request 177 * 178 * @tfm: AKCIPHER tfm handle allocated with crypto_alloc_akcipher() 179 * @gfp: allocation flags 180 * 181 * Return: allocated handle in case of success or NULL in case of an error. 182 */ 183 static inline struct akcipher_request *akcipher_request_alloc( 184 struct crypto_akcipher *tfm, gfp_t gfp) 185 { 186 struct akcipher_request *req; 187 188 req = kmalloc(sizeof(*req) + crypto_akcipher_reqsize(tfm), gfp); 189 if (likely(req)) 190 akcipher_request_set_tfm(req, tfm); 191 192 return req; 193 } 194 195 /** 196 * akcipher_request_free() -- zeroize and free public key request 197 * 198 * @req: request to free 199 */ 200 static inline void akcipher_request_free(struct akcipher_request *req) 201 { 202 kzfree(req); 203 } 204 205 /** 206 * akcipher_request_set_callback() -- Sets an asynchronous callback. 207 * 208 * Callback will be called when an asynchronous operation on a given 209 * request is finished. 210 * 211 * @req: request that the callback will be set for 212 * @flgs: specify for instance if the operation may backlog 213 * @cmlp: callback which will be called 214 * @data: private data used by the caller 215 */ 216 static inline void akcipher_request_set_callback(struct akcipher_request *req, 217 u32 flgs, 218 crypto_completion_t cmpl, 219 void *data) 220 { 221 req->base.complete = cmpl; 222 req->base.data = data; 223 req->base.flags = flgs; 224 } 225 226 /** 227 * akcipher_request_set_crypt() -- Sets reqest parameters 228 * 229 * Sets parameters required by crypto operation 230 * 231 * @req: public key request 232 * @src: ptr to input parameter 233 * @dst: ptr of output parameter 234 * @src_len: size of the input buffer 235 * @dst_len: size of the output buffer. It will be updated by the 236 * implementation to reflect the acctual size of the result 237 */ 238 static inline void akcipher_request_set_crypt(struct akcipher_request *req, 239 void *src, void *dst, 240 unsigned int src_len, 241 unsigned int dst_len) 242 { 243 req->src = src; 244 req->dst = dst; 245 req->src_len = src_len; 246 req->dst_len = dst_len; 247 } 248 249 /** 250 * crypto_akcipher_encrypt() -- Invoke public key encrypt operation 251 * 252 * Function invokes the specific public key encrypt operation for a given 253 * public key algorithm 254 * 255 * @req: asymmetric key request 256 * 257 * Return: zero on success; error code in case of error 258 */ 259 static inline int crypto_akcipher_encrypt(struct akcipher_request *req) 260 { 261 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); 262 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 263 264 return alg->encrypt(req); 265 } 266 267 /** 268 * crypto_akcipher_decrypt() -- Invoke public key decrypt operation 269 * 270 * Function invokes the specific public key decrypt operation for a given 271 * public key algorithm 272 * 273 * @req: asymmetric key request 274 * 275 * Return: zero on success; error code in case of error 276 */ 277 static inline int crypto_akcipher_decrypt(struct akcipher_request *req) 278 { 279 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); 280 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 281 282 return alg->decrypt(req); 283 } 284 285 /** 286 * crypto_akcipher_sign() -- Invoke public key sign operation 287 * 288 * Function invokes the specific public key sign operation for a given 289 * public key algorithm 290 * 291 * @req: asymmetric key request 292 * 293 * Return: zero on success; error code in case of error 294 */ 295 static inline int crypto_akcipher_sign(struct akcipher_request *req) 296 { 297 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); 298 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 299 300 return alg->sign(req); 301 } 302 303 /** 304 * crypto_akcipher_verify() -- Invoke public key verify operation 305 * 306 * Function invokes the specific public key verify operation for a given 307 * public key algorithm 308 * 309 * @req: asymmetric key request 310 * 311 * Return: zero on success; error code in case of error 312 */ 313 static inline int crypto_akcipher_verify(struct akcipher_request *req) 314 { 315 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); 316 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 317 318 return alg->verify(req); 319 } 320 321 /** 322 * crypto_akcipher_setkey() -- Invoke public key setkey operation 323 * 324 * Function invokes the algorithm specific set key function, which knows 325 * how to decode and interpret the encoded key 326 * 327 * @tfm: tfm handle 328 * @key: BER encoded private or public key 329 * @keylen: length of the key 330 * 331 * Return: zero on success; error code in case of error 332 */ 333 static inline int crypto_akcipher_setkey(struct crypto_akcipher *tfm, void *key, 334 unsigned int keylen) 335 { 336 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 337 338 return alg->setkey(tfm, key, keylen); 339 } 340 #endif 341