include/crypto/akcipher.h

   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