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: Source data 22 * @dst: Destination data 23 * @src_len: Size of the input buffer 24 * @dst_len: Size of the output buffer. It needs to be at least 25 * as big as the expected result depending on the operation 26 * After operation it will be updated with the actual size of the 27 * result. 28 * In case of error where the dst sgl size 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 struct scatterlist *src; 35 struct scatterlist *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 encrypt 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 * @set_pub_key: Function invokes the algorithm specific set public key 71 * function, which knows how to decode and interpret 72 * the BER encoded public key 73 * @set_priv_key: Function invokes the algorithm specific set private key 74 * function, which knows how to decode and interpret 75 * the BER encoded private key 76 * @max_size: Function returns dest buffer size required for a given key. 77 * @init: Initialize the cryptographic transformation object. 78 * This function is used to initialize the cryptographic 79 * transformation object. This function is called only once at 80 * the instantiation time, right after the transformation context 81 * was allocated. In case the cryptographic hardware has some 82 * special requirements which need to be handled by software, this 83 * function shall check for the precise requirement of the 84 * transformation and put any software fallbacks in place. 85 * @exit: Deinitialize the cryptographic transformation object. This is a 86 * counterpart to @init, used to remove various changes set in 87 * @init. 88 * 89 * @reqsize: Request context size required by algorithm implementation 90 * @base: Common crypto API algorithm data structure 91 */ 92 struct akcipher_alg { 93 int (*sign)(struct akcipher_request *req); 94 int (*verify)(struct akcipher_request *req); 95 int (*encrypt)(struct akcipher_request *req); 96 int (*decrypt)(struct akcipher_request *req); 97 int (*set_pub_key)(struct crypto_akcipher *tfm, const void *key, 98 unsigned int keylen); 99 int (*set_priv_key)(struct crypto_akcipher *tfm, const void *key, 100 unsigned int keylen); 101 int (*max_size)(struct crypto_akcipher *tfm); 102 int (*init)(struct crypto_akcipher *tfm); 103 void (*exit)(struct crypto_akcipher *tfm); 104 105 unsigned int reqsize; 106 struct crypto_alg base; 107 }; 108 109 /** 110 * DOC: Generic Public Key API 111 * 112 * The Public Key API is used with the algorithms of type 113 * CRYPTO_ALG_TYPE_AKCIPHER (listed as type "akcipher" in /proc/crypto) 114 */ 115 116 /** 117 * crypto_alloc_akcipher() - allocate AKCIPHER tfm handle 118 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 119 * public key algorithm e.g. "rsa" 120 * @type: specifies the type of the algorithm 121 * @mask: specifies the mask for the algorithm 122 * 123 * Allocate a handle for public key algorithm. The returned struct 124 * crypto_akcipher is the handle that is required for any subsequent 125 * API invocation for the public key operations. 126 * 127 * Return: allocated handle in case of success; IS_ERR() is true in case 128 * of an error, PTR_ERR() returns the error code. 129 */ 130 struct crypto_akcipher *crypto_alloc_akcipher(const char *alg_name, u32 type, 131 u32 mask); 132 133 static inline struct crypto_tfm *crypto_akcipher_tfm( 134 struct crypto_akcipher *tfm) 135 { 136 return &tfm->base; 137 } 138 139 static inline struct akcipher_alg *__crypto_akcipher_alg(struct crypto_alg *alg) 140 { 141 return container_of(alg, struct akcipher_alg, base); 142 } 143 144 static inline struct crypto_akcipher *__crypto_akcipher_tfm( 145 struct crypto_tfm *tfm) 146 { 147 return container_of(tfm, struct crypto_akcipher, base); 148 } 149 150 static inline struct akcipher_alg *crypto_akcipher_alg( 151 struct crypto_akcipher *tfm) 152 { 153 return __crypto_akcipher_alg(crypto_akcipher_tfm(tfm)->__crt_alg); 154 } 155 156 static inline unsigned int crypto_akcipher_reqsize(struct crypto_akcipher *tfm) 157 { 158 return crypto_akcipher_alg(tfm)->reqsize; 159 } 160 161 static inline void akcipher_request_set_tfm(struct akcipher_request *req, 162 struct crypto_akcipher *tfm) 163 { 164 req->base.tfm = crypto_akcipher_tfm(tfm); 165 } 166 167 static inline struct crypto_akcipher *crypto_akcipher_reqtfm( 168 struct akcipher_request *req) 169 { 170 return __crypto_akcipher_tfm(req->base.tfm); 171 } 172 173 /** 174 * crypto_free_akcipher() - free AKCIPHER tfm handle 175 * 176 * @tfm: AKCIPHER tfm handle allocated with crypto_alloc_akcipher() 177 */ 178 static inline void crypto_free_akcipher(struct crypto_akcipher *tfm) 179 { 180 crypto_destroy_tfm(tfm, crypto_akcipher_tfm(tfm)); 181 } 182 183 /** 184 * akcipher_request_alloc() - allocates public key request 185 * 186 * @tfm: AKCIPHER tfm handle allocated with crypto_alloc_akcipher() 187 * @gfp: allocation flags 188 * 189 * Return: allocated handle in case of success or NULL in case of an error. 190 */ 191 static inline struct akcipher_request *akcipher_request_alloc( 192 struct crypto_akcipher *tfm, gfp_t gfp) 193 { 194 struct akcipher_request *req; 195 196 req = kmalloc(sizeof(*req) + crypto_akcipher_reqsize(tfm), gfp); 197 if (likely(req)) 198 akcipher_request_set_tfm(req, tfm); 199 200 return req; 201 } 202 203 /** 204 * akcipher_request_free() - zeroize and free public key request 205 * 206 * @req: request to free 207 */ 208 static inline void akcipher_request_free(struct akcipher_request *req) 209 { 210 kzfree(req); 211 } 212 213 /** 214 * akcipher_request_set_callback() - Sets an asynchronous callback. 215 * 216 * Callback will be called when an asynchronous operation on a given 217 * request is finished. 218 * 219 * @req: request that the callback will be set for 220 * @flgs: specify for instance if the operation may backlog 221 * @cmpl: callback which will be called 222 * @data: private data used by the caller 223 */ 224 static inline void akcipher_request_set_callback(struct akcipher_request *req, 225 u32 flgs, 226 crypto_completion_t cmpl, 227 void *data) 228 { 229 req->base.complete = cmpl; 230 req->base.data = data; 231 req->base.flags = flgs; 232 } 233 234 /** 235 * akcipher_request_set_crypt() - Sets request parameters 236 * 237 * Sets parameters required by crypto operation 238 * 239 * @req: public key request 240 * @src: ptr to input scatter list 241 * @dst: ptr to output scatter list 242 * @src_len: size of the src input scatter list to be processed 243 * @dst_len: size of the dst output scatter list 244 */ 245 static inline void akcipher_request_set_crypt(struct akcipher_request *req, 246 struct scatterlist *src, 247 struct scatterlist *dst, 248 unsigned int src_len, 249 unsigned int dst_len) 250 { 251 req->src = src; 252 req->dst = dst; 253 req->src_len = src_len; 254 req->dst_len = dst_len; 255 } 256 257 /** 258 * crypto_akcipher_maxsize() - Get len for output buffer 259 * 260 * Function returns the dest buffer size required for a given key 261 * 262 * @tfm: AKCIPHER tfm handle allocated with crypto_alloc_akcipher() 263 * 264 * Return: minimum len for output buffer or error code in key hasn't been set 265 */ 266 static inline int crypto_akcipher_maxsize(struct crypto_akcipher *tfm) 267 { 268 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 269 270 return alg->max_size(tfm); 271 } 272 273 /** 274 * crypto_akcipher_encrypt() - Invoke public key encrypt operation 275 * 276 * Function invokes the specific public key encrypt operation for a given 277 * public key algorithm 278 * 279 * @req: asymmetric key request 280 * 281 * Return: zero on success; error code in case of error 282 */ 283 static inline int crypto_akcipher_encrypt(struct akcipher_request *req) 284 { 285 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); 286 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 287 288 return alg->encrypt(req); 289 } 290 291 /** 292 * crypto_akcipher_decrypt() - Invoke public key decrypt operation 293 * 294 * Function invokes the specific public key decrypt operation for a given 295 * public key algorithm 296 * 297 * @req: asymmetric key request 298 * 299 * Return: zero on success; error code in case of error 300 */ 301 static inline int crypto_akcipher_decrypt(struct akcipher_request *req) 302 { 303 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); 304 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 305 306 return alg->decrypt(req); 307 } 308 309 /** 310 * crypto_akcipher_sign() - Invoke public key sign operation 311 * 312 * Function invokes the specific public key sign operation for a given 313 * public key algorithm 314 * 315 * @req: asymmetric key request 316 * 317 * Return: zero on success; error code in case of error 318 */ 319 static inline int crypto_akcipher_sign(struct akcipher_request *req) 320 { 321 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); 322 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 323 324 return alg->sign(req); 325 } 326 327 /** 328 * crypto_akcipher_verify() - Invoke public key verify operation 329 * 330 * Function invokes the specific public key verify operation for a given 331 * public key algorithm 332 * 333 * @req: asymmetric key request 334 * 335 * Return: zero on success; error code in case of error 336 */ 337 static inline int crypto_akcipher_verify(struct akcipher_request *req) 338 { 339 struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); 340 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 341 342 return alg->verify(req); 343 } 344 345 /** 346 * crypto_akcipher_set_pub_key() - Invoke set public key operation 347 * 348 * Function invokes the algorithm specific set key function, which knows 349 * how to decode and interpret the encoded key 350 * 351 * @tfm: tfm handle 352 * @key: BER encoded public key 353 * @keylen: length of the key 354 * 355 * Return: zero on success; error code in case of error 356 */ 357 static inline int crypto_akcipher_set_pub_key(struct crypto_akcipher *tfm, 358 const void *key, 359 unsigned int keylen) 360 { 361 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 362 363 return alg->set_pub_key(tfm, key, keylen); 364 } 365 366 /** 367 * crypto_akcipher_set_priv_key() - Invoke set private key operation 368 * 369 * Function invokes the algorithm specific set key function, which knows 370 * how to decode and interpret the encoded key 371 * 372 * @tfm: tfm handle 373 * @key: BER encoded private key 374 * @keylen: length of the key 375 * 376 * Return: zero on success; error code in case of error 377 */ 378 static inline int crypto_akcipher_set_priv_key(struct crypto_akcipher *tfm, 379 const void *key, 380 unsigned int keylen) 381 { 382 struct akcipher_alg *alg = crypto_akcipher_alg(tfm); 383 384 return alg->set_priv_key(tfm, key, keylen); 385 } 386 #endif 387