apr_crypto.h revision 362181
1/* Licensed to the Apache Software Foundation (ASF) under one or more 2 * contributor license agreements. See the NOTICE file distributed with 3 * this work for additional information regarding copyright ownership. 4 * The ASF licenses this file to You under the Apache License, Version 2.0 5 * (the "License"); you may not use this file except in compliance with 6 * the License. You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef APR_CRYPTO_H 18#define APR_CRYPTO_H 19 20#include "apu.h" 21#include "apr_pools.h" 22#include "apr_tables.h" 23#include "apr_hash.h" 24#include "apu_errno.h" 25 26#ifdef __cplusplus 27extern "C" { 28#endif 29 30/** 31 * @file apr_crypto.h 32 * @brief APR-UTIL Crypto library 33 */ 34/** 35 * @defgroup APR_Util_Crypto Crypto routines 36 * @ingroup APR_Util 37 * @{ 38 */ 39 40#if APU_HAVE_CRYPTO 41 42#ifndef APU_CRYPTO_RECOMMENDED_DRIVER 43#if APU_HAVE_COMMONCRYPTO 44#define APU_CRYPTO_RECOMMENDED_DRIVER "commoncrypto" 45#else 46#if APU_HAVE_OPENSSL 47#define APU_CRYPTO_RECOMMENDED_DRIVER "openssl" 48#else 49#if APU_HAVE_NSS 50#define APU_CRYPTO_RECOMMENDED_DRIVER "nss" 51#else 52#if APU_HAVE_MSCNG 53#define APU_CRYPTO_RECOMMENDED_DRIVER "mscng" 54#else 55#if APU_HAVE_MSCAPI 56#define APU_CRYPTO_RECOMMENDED_DRIVER "mscapi" 57#else 58#endif 59#endif 60#endif 61#endif 62#endif 63#endif 64 65/** 66 * Symmetric Key types understood by the library. 67 * 68 * NOTE: It is expected that this list will grow over time. 69 * 70 * Interoperability Matrix: 71 * 72 * The matrix is based on the testcrypto.c unit test, which attempts to 73 * test whether a simple encrypt/decrypt will succeed, as well as testing 74 * whether an encrypted string by one library can be decrypted by the 75 * others. 76 * 77 * Some libraries will successfully encrypt and decrypt their own data, 78 * but won't decrypt data from another library. It is hoped that over 79 * time these anomalies will be found and fixed, but until then it is 80 * recommended that ciphers are chosen that interoperate across platform. 81 * 82 * An X below means the test passes, it does not necessarily mean that 83 * encryption performed is correct or secure. Applications should stick 84 * to ciphers that pass the interoperablity tests on the right hand side 85 * of the table. 86 * 87 * Aligned data is data whose length is a multiple of the block size for 88 * the chosen cipher. Padded data is data that is not aligned by block 89 * size and must be padded by the crypto library. 90 * 91 * OpenSSL CommonCrypto NSS Interop 92 * Align Pad Align Pad Align Pad Align Pad 93 * 3DES_192/CBC X X X X X X X X 94 * 3DES_192/ECB X X X X 95 * AES_256/CBC X X X X X X X X 96 * AES_256/ECB X X X X X X 97 * AES_192/CBC X X X X X X 98 * AES_192/ECB X X X X X 99 * AES_128/CBC X X X X X X 100 * AES_128/ECB X X X X X 101 * 102 * Conclusion: for padded data, use 3DES_192/CBC or AES_256/CBC. For 103 * aligned data, use 3DES_192/CBC, AES_256/CBC or AES_256/ECB. 104 */ 105 106typedef enum 107{ 108 APR_KEY_NONE, APR_KEY_3DES_192, /** 192 bit (3-Key) 3DES */ 109 APR_KEY_AES_128, /** 128 bit AES */ 110 APR_KEY_AES_192, /** 192 bit AES */ 111 APR_KEY_AES_256 112/** 256 bit AES */ 113} apr_crypto_block_key_type_e; 114 115typedef enum 116{ 117 APR_MODE_NONE, /** An error condition */ 118 APR_MODE_ECB, /** Electronic Code Book */ 119 APR_MODE_CBC 120/** Cipher Block Chaining */ 121} apr_crypto_block_key_mode_e; 122 123/* These are opaque structs. Instantiation is up to each backend */ 124typedef struct apr_crypto_driver_t apr_crypto_driver_t; 125typedef struct apr_crypto_t apr_crypto_t; 126typedef struct apr_crypto_config_t apr_crypto_config_t; 127typedef struct apr_crypto_key_t apr_crypto_key_t; 128typedef struct apr_crypto_block_t apr_crypto_block_t; 129 130typedef struct apr_crypto_block_key_type_t { 131 apr_crypto_block_key_type_e type; 132 int keysize; 133 int blocksize; 134 int ivsize; 135} apr_crypto_block_key_type_t; 136 137typedef struct apr_crypto_block_key_mode_t { 138 apr_crypto_block_key_mode_e mode; 139} apr_crypto_block_key_mode_t; 140 141typedef struct apr_crypto_passphrase_t { 142 const char *pass; 143 apr_size_t passLen; 144 const unsigned char * salt; 145 apr_size_t saltLen; 146 int iterations; 147} apr_crypto_passphrase_t; 148 149typedef struct apr_crypto_secret_t { 150 const unsigned char *secret; 151 apr_size_t secretLen; 152} apr_crypto_secret_t; 153 154typedef enum { 155 /** Key is derived from a passphrase */ 156 APR_CRYPTO_KTYPE_PASSPHRASE = 1, 157 /** Key is derived from a raw key */ 158 APR_CRYPTO_KTYPE_SECRET = 2, 159} apr_crypto_key_type; 160 161typedef struct apr_crypto_key_rec_t { 162 apr_crypto_key_type ktype; 163 apr_crypto_block_key_type_e type; 164 apr_crypto_block_key_mode_e mode; 165 int pad; 166 union { 167 apr_crypto_passphrase_t passphrase; 168 apr_crypto_secret_t secret; 169 } k; 170} apr_crypto_key_rec_t; 171 172/** 173 * @brief Perform once-only initialisation. Call once only. 174 * 175 * @param pool - pool to register any shutdown cleanups, etc 176 * @return APR_NOTIMPL in case of no crypto support. 177 */ 178APU_DECLARE(apr_status_t) apr_crypto_init(apr_pool_t *pool); 179 180/** 181 * @brief Zero out the buffer provided when the pool is cleaned up. 182 * 183 * @param pool - pool to register the cleanup 184 * @param buffer - buffer to zero out 185 * @param size - size of the buffer to zero out 186 */ 187APU_DECLARE(apr_status_t) apr_crypto_clear(apr_pool_t *pool, void *buffer, 188 apr_size_t size); 189 190/** 191 * @brief Always zero out the buffer provided, without being optimized out by 192 * the compiler. 193 * 194 * @param buffer - buffer to zero out 195 * @param size - size of the buffer to zero out 196 */ 197APU_DECLARE(apr_status_t) apr_crypto_memzero(void *buffer, apr_size_t size); 198 199/** 200 * @brief Timing attacks safe buffers comparison, where the executing time does 201 * not depend on the bytes compared but solely on the number of bytes. 202 * 203 * @param buf1 - first buffer to compare 204 * @param buf2 - second buffer to compare 205 * @param size - size of the buffers to compare 206 * @return 1 if the buffers are equals, 0 otherwise. 207 */ 208APU_DECLARE(int) apr_crypto_equals(const void *buf1, const void *buf2, 209 apr_size_t size); 210 211/** 212 * @brief Get the driver struct for a name 213 * 214 * @param driver - pointer to driver struct. 215 * @param name - driver name 216 * @param params - array of initialisation parameters 217 * @param result - result and error message on failure 218 * @param pool - (process) pool to register cleanup 219 * @return APR_SUCCESS for success 220 * @return APR_ENOTIMPL for no driver (when DSO not enabled) 221 * @return APR_EDSOOPEN if DSO driver file can't be opened 222 * @return APR_ESYMNOTFOUND if the driver file doesn't contain a driver 223 * @remarks NSS: the params can have "dir", "key3", "cert7" and "secmod" 224 * keys, each followed by an equal sign and a value. Such key/value pairs can 225 * be delimited by space or tab. If the value contains a space, surround the 226 * whole key value pair in quotes: "dir=My Directory". 227 * @remarks OpenSSL: currently no params are supported. 228 */ 229APU_DECLARE(apr_status_t) apr_crypto_get_driver( 230 const apr_crypto_driver_t **driver, 231 const char *name, const char *params, const apu_err_t **result, 232 apr_pool_t *pool); 233 234/** 235 * @brief Return the name of the driver. 236 * 237 * @param driver - The driver in use. 238 * @return The name of the driver. 239 */ 240APU_DECLARE(const char *) apr_crypto_driver_name( 241 const apr_crypto_driver_t *driver); 242 243/** 244 * @brief Get the result of the last operation on a context. If the result 245 * is NULL, the operation was successful. 246 * @param result - the result structure 247 * @param f - context pointer 248 * @return APR_SUCCESS for success 249 */ 250APU_DECLARE(apr_status_t) apr_crypto_error(const apu_err_t **result, 251 const apr_crypto_t *f); 252 253/** 254 * @brief Create a context for supporting encryption. Keys, certificates, 255 * algorithms and other parameters will be set per context. More than 256 * one context can be created at one time. A cleanup will be automatically 257 * registered with the given pool to guarantee a graceful shutdown. 258 * @param f - context pointer will be written here 259 * @param driver - driver to use 260 * @param params - array of key parameters 261 * @param pool - process pool 262 * @return APR_ENOENGINE when the engine specified does not exist. APR_EINITENGINE 263 * if the engine cannot be initialised. 264 * @remarks NSS: currently no params are supported. 265 * @remarks OpenSSL: the params can have "engine" as a key, followed by an equal 266 * sign and a value. 267 */ 268APU_DECLARE(apr_status_t) apr_crypto_make(apr_crypto_t **f, 269 const apr_crypto_driver_t *driver, const char *params, 270 apr_pool_t *pool); 271 272/** 273 * @brief Get a hash table of key types, keyed by the name of the type against 274 * a pointer to apr_crypto_block_key_type_t, which in turn begins with an 275 * integer. 276 * 277 * @param types - hashtable of key types keyed to constants. 278 * @param f - encryption context 279 * @return APR_SUCCESS for success 280 */ 281APU_DECLARE(apr_status_t) apr_crypto_get_block_key_types(apr_hash_t **types, 282 const apr_crypto_t *f); 283 284/** 285 * @brief Get a hash table of key modes, keyed by the name of the mode against 286 * a pointer to apr_crypto_block_key_mode_t, which in turn begins with an 287 * integer. 288 * 289 * @param modes - hashtable of key modes keyed to constants. 290 * @param f - encryption context 291 * @return APR_SUCCESS for success 292 */ 293APU_DECLARE(apr_status_t) apr_crypto_get_block_key_modes(apr_hash_t **modes, 294 const apr_crypto_t *f); 295 296/** 297 * @brief Create a key from the provided secret or passphrase. The key is cleaned 298 * up when the context is cleaned, and may be reused with multiple encryption 299 * or decryption operations. 300 * @note If *key is NULL, a apr_crypto_key_t will be created from a pool. If 301 * *key is not NULL, *key must point at a previously created structure. 302 * @param key The key returned, see note. 303 * @param rec The key record, from which the key will be derived. 304 * @param f The context to use. 305 * @param p The pool to use. 306 * @return Returns APR_ENOKEY if the pass phrase is missing or empty, or if a backend 307 * error occurred while generating the key. APR_ENOCIPHER if the type or mode 308 * is not supported by the particular backend. APR_EKEYTYPE if the key type is 309 * not known. APR_EPADDING if padding was requested but is not supported. 310 * APR_ENOTIMPL if not implemented. 311 */ 312APU_DECLARE(apr_status_t) apr_crypto_key(apr_crypto_key_t **key, 313 const apr_crypto_key_rec_t *rec, const apr_crypto_t *f, apr_pool_t *p); 314 315/** 316 * @brief Create a key from the given passphrase. By default, the PBKDF2 317 * algorithm is used to generate the key from the passphrase. It is expected 318 * that the same pass phrase will generate the same key, regardless of the 319 * backend crypto platform used. The key is cleaned up when the context 320 * is cleaned, and may be reused with multiple encryption or decryption 321 * operations. 322 * @note If *key is NULL, a apr_crypto_key_t will be created from a pool. If 323 * *key is not NULL, *key must point at a previously created structure. 324 * @param key The key returned, see note. 325 * @param ivSize The size of the initialisation vector will be returned, based 326 * on whether an IV is relevant for this type of crypto. 327 * @param pass The passphrase to use. 328 * @param passLen The passphrase length in bytes 329 * @param salt The salt to use. 330 * @param saltLen The salt length in bytes 331 * @param type 3DES_192, AES_128, AES_192, AES_256. 332 * @param mode Electronic Code Book / Cipher Block Chaining. 333 * @param doPad Pad if necessary. 334 * @param iterations Number of iterations to use in algorithm 335 * @param f The context to use. 336 * @param p The pool to use. 337 * @return Returns APR_ENOKEY if the pass phrase is missing or empty, or if a backend 338 * error occurred while generating the key. APR_ENOCIPHER if the type or mode 339 * is not supported by the particular backend. APR_EKEYTYPE if the key type is 340 * not known. APR_EPADDING if padding was requested but is not supported. 341 * APR_ENOTIMPL if not implemented. 342 * @deprecated Replaced by apr_crypto_key(). 343 */ 344APU_DECLARE(apr_status_t) apr_crypto_passphrase(apr_crypto_key_t **key, 345 apr_size_t *ivSize, const char *pass, apr_size_t passLen, 346 const unsigned char * salt, apr_size_t saltLen, 347 const apr_crypto_block_key_type_e type, 348 const apr_crypto_block_key_mode_e mode, const int doPad, 349 const int iterations, const apr_crypto_t *f, apr_pool_t *p); 350 351/** 352 * @brief Initialise a context for encrypting arbitrary data using the given key. 353 * @note If *ctx is NULL, a apr_crypto_block_t will be created from a pool. If 354 * *ctx is not NULL, *ctx must point at a previously created structure. 355 * @param ctx The block context returned, see note. 356 * @param iv Optional initialisation vector. If the buffer pointed to is NULL, 357 * an IV will be created at random, in space allocated from the pool. 358 * If the buffer pointed to is not NULL, the IV in the buffer will be 359 * used. 360 * @param key The key structure to use. 361 * @param blockSize The block size of the cipher. 362 * @param p The pool to use. 363 * @return Returns APR_ENOIV if an initialisation vector is required but not specified. 364 * Returns APR_EINIT if the backend failed to initialise the context. Returns 365 * APR_ENOTIMPL if not implemented. 366 */ 367APU_DECLARE(apr_status_t) apr_crypto_block_encrypt_init( 368 apr_crypto_block_t **ctx, const unsigned char **iv, 369 const apr_crypto_key_t *key, apr_size_t *blockSize, apr_pool_t *p); 370 371/** 372 * @brief Encrypt data provided by in, write it to out. 373 * @note The number of bytes written will be written to outlen. If 374 * out is NULL, outlen will contain the maximum size of the 375 * buffer needed to hold the data, including any data 376 * generated by apr_crypto_block_encrypt_finish below. If *out points 377 * to NULL, a buffer sufficiently large will be created from 378 * the pool provided. If *out points to a not-NULL value, this 379 * value will be used as a buffer instead. 380 * @param out Address of a buffer to which data will be written, 381 * see note. 382 * @param outlen Length of the output will be written here. 383 * @param in Address of the buffer to read. 384 * @param inlen Length of the buffer to read. 385 * @param ctx The block context to use. 386 * @return APR_ECRYPT if an error occurred. Returns APR_ENOTIMPL if 387 * not implemented. 388 */ 389APU_DECLARE(apr_status_t) apr_crypto_block_encrypt(unsigned char **out, 390 apr_size_t *outlen, const unsigned char *in, apr_size_t inlen, 391 apr_crypto_block_t *ctx); 392 393/** 394 * @brief Encrypt final data block, write it to out. 395 * @note If necessary the final block will be written out after being 396 * padded. Typically the final block will be written to the 397 * same buffer used by apr_crypto_block_encrypt, offset by the 398 * number of bytes returned as actually written by the 399 * apr_crypto_block_encrypt() call. After this call, the context 400 * is cleaned and can be reused by apr_crypto_block_encrypt_init(). 401 * @param out Address of a buffer to which data will be written. This 402 * buffer must already exist, and is usually the same 403 * buffer used by apr_evp_crypt(). See note. 404 * @param outlen Length of the output will be written here. 405 * @param ctx The block context to use. 406 * @return APR_ECRYPT if an error occurred. 407 * @return APR_EPADDING if padding was enabled and the block was incorrectly 408 * formatted. 409 * @return APR_ENOTIMPL if not implemented. 410 */ 411APU_DECLARE(apr_status_t) apr_crypto_block_encrypt_finish(unsigned char *out, 412 apr_size_t *outlen, apr_crypto_block_t *ctx); 413 414/** 415 * @brief Initialise a context for decrypting arbitrary data using the given key. 416 * @note If *ctx is NULL, a apr_crypto_block_t will be created from a pool. If 417 * *ctx is not NULL, *ctx must point at a previously created structure. 418 * @param ctx The block context returned, see note. 419 * @param blockSize The block size of the cipher. 420 * @param iv Optional initialisation vector. 421 * @param key The key structure to use. 422 * @param p The pool to use. 423 * @return Returns APR_ENOIV if an initialisation vector is required but not specified. 424 * Returns APR_EINIT if the backend failed to initialise the context. Returns 425 * APR_ENOTIMPL if not implemented. 426 */ 427APU_DECLARE(apr_status_t) apr_crypto_block_decrypt_init( 428 apr_crypto_block_t **ctx, apr_size_t *blockSize, 429 const unsigned char *iv, const apr_crypto_key_t *key, apr_pool_t *p); 430 431/** 432 * @brief Decrypt data provided by in, write it to out. 433 * @note The number of bytes written will be written to outlen. If 434 * out is NULL, outlen will contain the maximum size of the 435 * buffer needed to hold the data, including any data 436 * generated by apr_crypto_block_decrypt_finish below. If *out points 437 * to NULL, a buffer sufficiently large will be created from 438 * the pool provided. If *out points to a not-NULL value, this 439 * value will be used as a buffer instead. 440 * @param out Address of a buffer to which data will be written, 441 * see note. 442 * @param outlen Length of the output will be written here. 443 * @param in Address of the buffer to read. 444 * @param inlen Length of the buffer to read. 445 * @param ctx The block context to use. 446 * @return APR_ECRYPT if an error occurred. Returns APR_ENOTIMPL if 447 * not implemented. 448 */ 449APU_DECLARE(apr_status_t) apr_crypto_block_decrypt(unsigned char **out, 450 apr_size_t *outlen, const unsigned char *in, apr_size_t inlen, 451 apr_crypto_block_t *ctx); 452 453/** 454 * @brief Decrypt final data block, write it to out. 455 * @note If necessary the final block will be written out after being 456 * padded. Typically the final block will be written to the 457 * same buffer used by apr_crypto_block_decrypt, offset by the 458 * number of bytes returned as actually written by the 459 * apr_crypto_block_decrypt() call. After this call, the context 460 * is cleaned and can be reused by apr_crypto_block_decrypt_init(). 461 * @param out Address of a buffer to which data will be written. This 462 * buffer must already exist, and is usually the same 463 * buffer used by apr_evp_crypt(). See note. 464 * @param outlen Length of the output will be written here. 465 * @param ctx The block context to use. 466 * @return APR_ECRYPT if an error occurred. 467 * @return APR_EPADDING if padding was enabled and the block was incorrectly 468 * formatted. 469 * @return APR_ENOTIMPL if not implemented. 470 */ 471APU_DECLARE(apr_status_t) apr_crypto_block_decrypt_finish(unsigned char *out, 472 apr_size_t *outlen, apr_crypto_block_t *ctx); 473 474/** 475 * @brief Clean encryption / decryption context. 476 * @note After cleanup, a context is free to be reused if necessary. 477 * @param ctx The block context to use. 478 * @return Returns APR_ENOTIMPL if not supported. 479 */ 480APU_DECLARE(apr_status_t) apr_crypto_block_cleanup(apr_crypto_block_t *ctx); 481 482/** 483 * @brief Clean encryption / decryption context. 484 * @note After cleanup, a context is free to be reused if necessary. 485 * @param f The context to use. 486 * @return Returns APR_ENOTIMPL if not supported. 487 */ 488APU_DECLARE(apr_status_t) apr_crypto_cleanup(apr_crypto_t *f); 489 490/** 491 * @brief Shutdown the crypto library. 492 * @note After shutdown, it is expected that the init function can be called again. 493 * @param driver - driver to use 494 * @return Returns APR_ENOTIMPL if not supported. 495 */ 496APU_DECLARE(apr_status_t) apr_crypto_shutdown( 497 const apr_crypto_driver_t *driver); 498 499#endif /* APU_HAVE_CRYPTO */ 500 501/** @} */ 502 503#ifdef __cplusplus 504} 505#endif 506 507#endif 508