/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef APR_CRYPTO_H
#define APR_CRYPTO_H
#include "apu.h"
#include "apr_pools.h"
#include "apr_tables.h"
#include "apr_hash.h"
#include "apu_errno.h"
#ifdef __cplusplus
extern "C" {
#endif
/**
* @file apr_crypto.h
* @brief APR-UTIL Crypto library
*/
/**
* @defgroup APR_Util_Crypto Crypto routines
* @ingroup APR_Util
* @{
*/
#if APU_HAVE_CRYPTO
#ifndef APU_CRYPTO_RECOMMENDED_DRIVER
#if APU_HAVE_OPENSSL
#define APU_CRYPTO_RECOMMENDED_DRIVER "openssl"
#else
#if APU_HAVE_NSS
#define APU_CRYPTO_RECOMMENDED_DRIVER "nss"
#else
#if APU_HAVE_MSCNG
#define APU_CRYPTO_RECOMMENDED_DRIVER "mscng"
#else
#if APU_HAVE_MSCAPI
#define APU_CRYPTO_RECOMMENDED_DRIVER "mscapi"
#else
#endif
#endif
#endif
#endif
#endif
/**
* Symmetric Key types understood by the library.
*
* NOTE: It is expected that this list will grow over time.
*
* Interoperability Matrix:
*
* The matrix is based on the testcrypto.c unit test, which attempts to
* test whether a simple encrypt/decrypt will succeed, as well as testing
* whether an encrypted string by one library can be decrypted by the
* others.
*
* Some libraries will successfully encrypt and decrypt their own data,
* but won't decrypt data from another library. It is hoped that over
* time these anomalies will be found and fixed, but until then it is
* recommended that ciphers are chosen that interoperate across platform.
*
* An X below means the test passes, it does not necessarily mean that
* encryption performed is correct or secure. Applications should stick
* to ciphers that pass the interoperablity tests on the right hand side
* of the table.
*
* Aligned data is data whose length is a multiple of the block size for
* the chosen cipher. Padded data is data that is not aligned by block
* size and must be padded by the crypto library.
*
* OpenSSL NSS Interop
* Align Pad Align Pad Align Pad
* 3DES_192/CBC X X X X X X
* 3DES_192/ECB X X
* AES_256/CBC X X X X X X
* AES_256/ECB X X X X
* AES_192/CBC X X X X
* AES_192/ECB X X X
* AES_128/CBC X X X X
* AES_128/ECB X X X
*
* Conclusion: for padded data, use 3DES_192/CBC or AES_256/CBC. For
* aligned data, use 3DES_192/CBC, AES_256/CBC or AES_256/ECB.
*/
typedef enum
{
APR_KEY_NONE, APR_KEY_3DES_192, /** 192 bit (3-Key) 3DES */
APR_KEY_AES_128, /** 128 bit AES */
APR_KEY_AES_192, /** 192 bit AES */
APR_KEY_AES_256
/** 256 bit AES */
} apr_crypto_block_key_type_e;
typedef enum
{
APR_MODE_NONE, /** An error condition */
APR_MODE_ECB, /** Electronic Code Book */
APR_MODE_CBC
/** Cipher Block Chaining */
} apr_crypto_block_key_mode_e;
/* These are opaque structs. Instantiation is up to each backend */
typedef struct apr_crypto_driver_t apr_crypto_driver_t;
typedef struct apr_crypto_t apr_crypto_t;
typedef struct apr_crypto_config_t apr_crypto_config_t;
typedef struct apr_crypto_key_t apr_crypto_key_t;
typedef struct apr_crypto_block_t apr_crypto_block_t;
/**
* @brief Perform once-only initialisation. Call once only.
*
* @param pool - pool to register any shutdown cleanups, etc
* @return APR_NOTIMPL in case of no crypto support.
*/
APU_DECLARE(apr_status_t) apr_crypto_init(apr_pool_t *pool);
/**
* @brief Register a cleanup to zero out the buffer provided
* when the pool is cleaned up.
*
* @param pool - pool to register the cleanup
* @param buffer - buffer to zero out
* @param size - size of the buffer to zero out
*/
APU_DECLARE(apr_status_t) apr_crypto_clear(apr_pool_t *pool, void *buffer,
apr_size_t size);
/**
* @brief Get the driver struct for a name
*
* @param driver - pointer to driver struct.
* @param name - driver name
* @param params - array of initialisation parameters
* @param result - result and error message on failure
* @param pool - (process) pool to register cleanup
* @return APR_SUCCESS for success
* @return APR_ENOTIMPL for no driver (when DSO not enabled)
* @return APR_EDSOOPEN if DSO driver file can't be opened
* @return APR_ESYMNOTFOUND if the driver file doesn't contain a driver
* @remarks NSS: the params can have "dir", "key3", "cert7" and "secmod"
* keys, each followed by an equal sign and a value. Such key/value pairs can
* be delimited by space or tab. If the value contains a space, surround the
* whole key value pair in quotes: "dir=My Directory".
* @remarks OpenSSL: currently no params are supported.
*/
APU_DECLARE(apr_status_t) apr_crypto_get_driver(
const apr_crypto_driver_t **driver,
const char *name, const char *params, const apu_err_t **result,
apr_pool_t *pool);
/**
* @brief Return the name of the driver.
*
* @param driver - The driver in use.
* @return The name of the driver.
*/
APU_DECLARE(const char *) apr_crypto_driver_name(
const apr_crypto_driver_t *driver);
/**
* @brief Get the result of the last operation on a context. If the result
* is NULL, the operation was successful.
* @param result - the result structure
* @param f - context pointer
* @return APR_SUCCESS for success
*/
APU_DECLARE(apr_status_t) apr_crypto_error(const apu_err_t **result,
const apr_crypto_t *f);
/**
* @brief Create a context for supporting encryption. Keys, certificates,
* algorithms and other parameters will be set per context. More than
* one context can be created at one time. A cleanup will be automatically
* registered with the given pool to guarantee a graceful shutdown.
* @param f - context pointer will be written here
* @param driver - driver to use
* @param params - array of key parameters
* @param pool - process pool
* @return APR_ENOENGINE when the engine specified does not exist. APR_EINITENGINE
* if the engine cannot be initialised.
* @remarks NSS: currently no params are supported.
* @remarks OpenSSL: the params can have "engine" as a key, followed by an equal
* sign and a value.
*/
APU_DECLARE(apr_status_t) apr_crypto_make(apr_crypto_t **f,
const apr_crypto_driver_t *driver, const char *params,
apr_pool_t *pool);
/**
* @brief Get a hash table of key types, keyed by the name of the type against
* an integer pointer constant.
*
* @param types - hashtable of key types keyed to constants.
* @param f - encryption context
* @return APR_SUCCESS for success
*/
APU_DECLARE(apr_status_t) apr_crypto_get_block_key_types(apr_hash_t **types,
const apr_crypto_t *f);
/**
* @brief Get a hash table of key modes, keyed by the name of the mode against
* an integer pointer constant.
*
* @param modes - hashtable of key modes keyed to constants.
* @param f - encryption context
* @return APR_SUCCESS for success
*/
APU_DECLARE(apr_status_t) apr_crypto_get_block_key_modes(apr_hash_t **modes,
const apr_crypto_t *f);
/**
* @brief Create a key from the given passphrase. By default, the PBKDF2
* algorithm is used to generate the key from the passphrase. It is expected
* that the same pass phrase will generate the same key, regardless of the
* backend crypto platform used. The key is cleaned up when the context
* is cleaned, and may be reused with multiple encryption or decryption
* operations.
* @note If *key is NULL, a apr_crypto_key_t will be created from a pool. If
* *key is not NULL, *key must point at a previously created structure.
* @param key The key returned, see note.
* @param ivSize The size of the initialisation vector will be returned, based
* on whether an IV is relevant for this type of crypto.
* @param pass The passphrase to use.
* @param passLen The passphrase length in bytes
* @param salt The salt to use.
* @param saltLen The salt length in bytes
* @param type 3DES_192, AES_128, AES_192, AES_256.
* @param mode Electronic Code Book / Cipher Block Chaining.
* @param doPad Pad if necessary.
* @param iterations Number of iterations to use in algorithm
* @param f The context to use.
* @param p The pool to use.
* @return Returns APR_ENOKEY if the pass phrase is missing or empty, or if a backend
* error occurred while generating the key. APR_ENOCIPHER if the type or mode
* is not supported by the particular backend. APR_EKEYTYPE if the key type is
* not known. APR_EPADDING if padding was requested but is not supported.
* APR_ENOTIMPL if not implemented.
*/
APU_DECLARE(apr_status_t) apr_crypto_passphrase(apr_crypto_key_t **key,
apr_size_t *ivSize, const char *pass, apr_size_t passLen,
const unsigned char * salt, apr_size_t saltLen,
const apr_crypto_block_key_type_e type,
const apr_crypto_block_key_mode_e mode, const int doPad,
const int iterations, const apr_crypto_t *f, apr_pool_t *p);
/**
* @brief Initialise a context for encrypting arbitrary data using the given key.
* @note If *ctx is NULL, a apr_crypto_block_t will be created from a pool. If
* *ctx is not NULL, *ctx must point at a previously created structure.
* @param ctx The block context returned, see note.
* @param iv Optional initialisation vector. If the buffer pointed to is NULL,
* an IV will be created at random, in space allocated from the pool.
* If the buffer pointed to is not NULL, the IV in the buffer will be
* used.
* @param key The key structure to use.
* @param blockSize The block size of the cipher.
* @param p The pool to use.
* @return Returns APR_ENOIV if an initialisation vector is required but not specified.
* Returns APR_EINIT if the backend failed to initialise the context. Returns
* APR_ENOTIMPL if not implemented.
*/
APU_DECLARE(apr_status_t) apr_crypto_block_encrypt_init(
apr_crypto_block_t **ctx, const unsigned char **iv,
const apr_crypto_key_t *key, apr_size_t *blockSize, apr_pool_t *p);
/**
* @brief Encrypt data provided by in, write it to out.
* @note The number of bytes written will be written to outlen. If
* out is NULL, outlen will contain the maximum size of the
* buffer needed to hold the data, including any data
* generated by apr_crypto_block_encrypt_finish below. If *out points
* to NULL, a buffer sufficiently large will be created from
* the pool provided. If *out points to a not-NULL value, this
* value will be used as a buffer instead.
* @param out Address of a buffer to which data will be written,
* see note.
* @param outlen Length of the output will be written here.
* @param in Address of the buffer to read.
* @param inlen Length of the buffer to read.
* @param ctx The block context to use.
* @return APR_ECRYPT if an error occurred. Returns APR_ENOTIMPL if
* not implemented.
*/
APU_DECLARE(apr_status_t) apr_crypto_block_encrypt(unsigned char **out,
apr_size_t *outlen, const unsigned char *in, apr_size_t inlen,
apr_crypto_block_t *ctx);
/**
* @brief Encrypt final data block, write it to out.
* @note If necessary the final block will be written out after being
* padded. Typically the final block will be written to the
* same buffer used by apr_crypto_block_encrypt, offset by the
* number of bytes returned as actually written by the
* apr_crypto_block_encrypt() call. After this call, the context
* is cleaned and can be reused by apr_crypto_block_encrypt_init().
* @param out Address of a buffer to which data will be written. This
* buffer must already exist, and is usually the same
* buffer used by apr_evp_crypt(). See note.
* @param outlen Length of the output will be written here.
* @param ctx The block context to use.
* @return APR_ECRYPT if an error occurred.
* @return APR_EPADDING if padding was enabled and the block was incorrectly
* formatted.
* @return APR_ENOTIMPL if not implemented.
*/
APU_DECLARE(apr_status_t) apr_crypto_block_encrypt_finish(unsigned char *out,
apr_size_t *outlen, apr_crypto_block_t *ctx);
/**
* @brief Initialise a context for decrypting arbitrary data using the given key.
* @note If *ctx is NULL, a apr_crypto_block_t will be created from a pool. If
* *ctx is not NULL, *ctx must point at a previously created structure.
* @param ctx The block context returned, see note.
* @param blockSize The block size of the cipher.
* @param iv Optional initialisation vector.
* @param key The key structure to use.
* @param p The pool to use.
* @return Returns APR_ENOIV if an initialisation vector is required but not specified.
* Returns APR_EINIT if the backend failed to initialise the context. Returns
* APR_ENOTIMPL if not implemented.
*/
APU_DECLARE(apr_status_t) apr_crypto_block_decrypt_init(
apr_crypto_block_t **ctx, apr_size_t *blockSize,
const unsigned char *iv, const apr_crypto_key_t *key, apr_pool_t *p);
/**
* @brief Decrypt data provided by in, write it to out.
* @note The number of bytes written will be written to outlen. If
* out is NULL, outlen will contain the maximum size of the
* buffer needed to hold the data, including any data
* generated by apr_crypto_block_decrypt_finish below. If *out points
* to NULL, a buffer sufficiently large will be created from
* the pool provided. If *out points to a not-NULL value, this
* value will be used as a buffer instead.
* @param out Address of a buffer to which data will be written,
* see note.
* @param outlen Length of the output will be written here.
* @param in Address of the buffer to read.
* @param inlen Length of the buffer to read.
* @param ctx The block context to use.
* @return APR_ECRYPT if an error occurred. Returns APR_ENOTIMPL if
* not implemented.
*/
APU_DECLARE(apr_status_t) apr_crypto_block_decrypt(unsigned char **out,
apr_size_t *outlen, const unsigned char *in, apr_size_t inlen,
apr_crypto_block_t *ctx);
/**
* @brief Decrypt final data block, write it to out.
* @note If necessary the final block will be written out after being
* padded. Typically the final block will be written to the
* same buffer used by apr_crypto_block_decrypt, offset by the
* number of bytes returned as actually written by the
* apr_crypto_block_decrypt() call. After this call, the context
* is cleaned and can be reused by apr_crypto_block_decrypt_init().
* @param out Address of a buffer to which data will be written. This
* buffer must already exist, and is usually the same
* buffer used by apr_evp_crypt(). See note.
* @param outlen Length of the output will be written here.
* @param ctx The block context to use.
* @return APR_ECRYPT if an error occurred.
* @return APR_EPADDING if padding was enabled and the block was incorrectly
* formatted.
* @return APR_ENOTIMPL if not implemented.
*/
APU_DECLARE(apr_status_t) apr_crypto_block_decrypt_finish(unsigned char *out,
apr_size_t *outlen, apr_crypto_block_t *ctx);
/**
* @brief Clean encryption / decryption context.
* @note After cleanup, a context is free to be reused if necessary.
* @param ctx The block context to use.
* @return Returns APR_ENOTIMPL if not supported.
*/
APU_DECLARE(apr_status_t) apr_crypto_block_cleanup(apr_crypto_block_t *ctx);
/**
* @brief Clean encryption / decryption context.
* @note After cleanup, a context is free to be reused if necessary.
* @param f The context to use.
* @return Returns APR_ENOTIMPL if not supported.
*/
APU_DECLARE(apr_status_t) apr_crypto_cleanup(apr_crypto_t *f);
/**
* @brief Shutdown the crypto library.
* @note After shutdown, it is expected that the init function can be called again.
* @param driver - driver to use
* @return Returns APR_ENOTIMPL if not supported.
*/
APU_DECLARE(apr_status_t) apr_crypto_shutdown(
const apr_crypto_driver_t *driver);
#endif /* APU_HAVE_CRYPTO */
/** @} */
#ifdef __cplusplus
}
#endif
#endif