qemu/include/crypto/hash.h
Daniel P. Berrangé 769660955a include/crypto: clarify @result/@result_len for hash/hmac APIs
The @result parameter passed to hash/hmac APIs may either contain
a pre-allocated buffer, or a buffer can be allocated on the fly.
Clarify these two different usage models in the API docs.

Reviewed-by: Dorjoy Chowdhury <dorjoychy111@gmail.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2024-10-22 11:44:23 +01:00

343 lines
11 KiB
C

/*
* QEMU Crypto hash algorithms
*
* Copyright (c) 2024 Seagate Technology LLC and/or its Affiliates
* Copyright (c) 2015 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef QCRYPTO_HASH_H
#define QCRYPTO_HASH_H
#include "qapi/qapi-types-crypto.h"
#define QCRYPTO_HASH_DIGEST_LEN_MD5 16
#define QCRYPTO_HASH_DIGEST_LEN_SHA1 20
#define QCRYPTO_HASH_DIGEST_LEN_SHA224 28
#define QCRYPTO_HASH_DIGEST_LEN_SHA256 32
#define QCRYPTO_HASH_DIGEST_LEN_SHA384 48
#define QCRYPTO_HASH_DIGEST_LEN_SHA512 64
#define QCRYPTO_HASH_DIGEST_LEN_RIPEMD160 20
/* See also "QCryptoHashAlgo" defined in qapi/crypto.json */
typedef struct QCryptoHash QCryptoHash;
struct QCryptoHash {
QCryptoHashAlgo alg;
void *opaque;
void *driver;
};
/**
* qcrypto_hash_supports:
* @alg: the hash algorithm
*
* Determine if @alg hash algorithm is supported by the
* current configured build.
*
* Returns: true if the algorithm is supported, false otherwise
*/
gboolean qcrypto_hash_supports(QCryptoHashAlgo alg);
/**
* qcrypto_hash_digest_len:
* @alg: the hash algorithm
*
* Determine the size of the hash digest in bytes
*
* Returns: the digest length in bytes
*/
size_t qcrypto_hash_digest_len(QCryptoHashAlgo alg);
/**
* qcrypto_hash_bytesv:
* @alg: the hash algorithm
* @iov: the array of memory regions to hash
* @niov: the length of @iov
* @result: pointer to hold output hash
* @resultlen: pointer to hold length of @result
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash across all the memory regions
* present in @iov.
*
* If @result_len is set to a non-zero value by the caller, then
* @result must hold a pointer that is @result_len in size, and
* @result_len match the size of the hash output. The digest will
* be written into @result.
*
* If @result_len is set to zero, then this function will allocate
* a buffer to hold the hash output digest, storing a pointer to
* the buffer in @result, and setting @result_len to its size.
* The memory referenced in @result must be released with a call
* to g_free() when no longer required by the caller.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_bytesv(QCryptoHashAlgo alg,
const struct iovec *iov,
size_t niov,
uint8_t **result,
size_t *resultlen,
Error **errp);
/**
* qcrypto_hash_bytes:
* @alg: the hash algorithm
* @buf: the memory region to hash
* @len: the length of @buf
* @result: pointer to hold output hash
* @resultlen: pointer to hold length of @result
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash across all the memory region
* @buf of length @len.
*
* If @result_len is set to a non-zero value by the caller, then
* @result must hold a pointer that is @result_len in size, and
* @result_len match the size of the hash output. The digest will
* be written into @result.
*
* If @result_len is set to zero, then this function will allocate
* a buffer to hold the hash output digest, storing a pointer to
* the buffer in @result, and setting @result_len to its size.
* The memory referenced in @result must be released with a call
* to g_free() when no longer required by the caller.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_bytes(QCryptoHashAlgo alg,
const char *buf,
size_t len,
uint8_t **result,
size_t *resultlen,
Error **errp);
/**
* qcrypto_hash_digestv:
* @alg: the hash algorithm
* @iov: the array of memory regions to hash
* @niov: the length of @iov
* @digest: pointer to hold output hash
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash across all the memory regions
* present in @iov. The @digest pointer will be
* filled with the printable hex digest of the computed
* hash, which will be terminated by '\0'. The
* memory pointer in @digest must be released
* with a call to g_free() when no longer required.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_digestv(QCryptoHashAlgo alg,
const struct iovec *iov,
size_t niov,
char **digest,
Error **errp);
/**
* qcrypto_hash_updatev:
* @hash: hash object from qcrypto_hash_new
* @iov: the array of memory regions to hash
* @niov: the length of @iov
* @errp: pointer to a NULL-initialized error object
*
* Updates the given hash object with all the memory regions
* present in @iov.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_updatev(QCryptoHash *hash,
const struct iovec *iov,
size_t niov,
Error **errp);
/**
* qcrypto_hash_update:
* @hash: hash object from qcrypto_hash_new
* @buf: the memory region to hash
* @len: the length of @buf
* @errp: pointer to a NULL-initialized error object
*
* Updates the given hash object with the data from
* the given buffer.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_update(QCryptoHash *hash,
const char *buf,
size_t len,
Error **errp);
/**
* qcrypto_hash_finalize_digest:
* @hash: the hash object to finalize
* @digest: pointer to hold output hash
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash from the given hash object. Hash object
* is expected to have its data updated from the qcrypto_hash_update function.
* The @digest pointer will be filled with the printable hex digest of the
* computed hash, which will be terminated by '\0'. The memory pointer
* in @digest must be released with a call to g_free() when
* no longer required.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_finalize_digest(QCryptoHash *hash,
char **digest,
Error **errp);
/**
* qcrypto_hash_finalize_base64:
* @hash_ctx: hash object to finalize
* @base64: pointer to store the hash result in
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash from the given hash object. Hash object
* is expected to have it's data updated from the qcrypto_hash_update function.
* The @base64 pointer will be filled with the base64 encoding of the computed
* hash, which will be terminated by '\0'. The memory pointer in @base64
* must be released with a call to g_free() when no longer required.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_finalize_base64(QCryptoHash *hash,
char **base64,
Error **errp);
/**
* qcrypto_hash_finalize_bytes:
* @hash_ctx: hash object to finalize
* @result: pointer to store the hash result in
* @result_len: Pointer to store the length of the result in
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash from the given hash object. Hash object
* is expected to have it's data updated from the qcrypto_hash_update function.
*
* If @result_len is set to a non-zero value by the caller, then
* @result must hold a pointer that is @result_len in size, and
* @result_len match the size of the hash output. The digest will
* be written into @result.
*
* If @result_len is set to zero, then this function will allocate
* a buffer to hold the hash output digest, storing a pointer to
* the buffer in @result, and setting @result_len to its size.
* The memory referenced in @result must be released with a call
* to g_free() when no longer required by the caller.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_finalize_bytes(QCryptoHash *hash,
uint8_t **result,
size_t *result_len,
Error **errp);
/**
* qcrypto_hash_new:
* @alg: the hash algorithm
* @errp: pointer to a NULL-initialized error object
*
* Creates a new hashing context for the chosen algorithm for
* usage with qcrypto_hash_update.
*
* Returns: New hash object with the given algorithm, or NULL on error.
*/
QCryptoHash *qcrypto_hash_new(QCryptoHashAlgo alg, Error **errp);
/**
* qcrypto_hash_free:
* @hash: hash object to free
*
* Frees a hashing context for the chosen algorithm.
*/
void qcrypto_hash_free(QCryptoHash *hash);
G_DEFINE_AUTOPTR_CLEANUP_FUNC(QCryptoHash, qcrypto_hash_free)
/**
* qcrypto_hash_digest:
* @alg: the hash algorithm
* @buf: the memory region to hash
* @len: the length of @buf
* @digest: pointer to hold output hash
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash across all the memory region
* @buf of length @len. The @digest pointer will be
* filled with the printable hex digest of the computed
* hash, which will be terminated by '\0'. The
* memory pointer in @digest must be released
* with a call to g_free() when no longer required.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_digest(QCryptoHashAlgo alg,
const char *buf,
size_t len,
char **digest,
Error **errp);
/**
* qcrypto_hash_base64v:
* @alg: the hash algorithm
* @iov: the array of memory regions to hash
* @niov: the length of @iov
* @base64: pointer to hold output hash
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash across all the memory regions
* present in @iov. The @base64 pointer will be
* filled with the base64 encoding of the computed
* hash, which will be terminated by '\0'. The
* memory pointer in @base64 must be released
* with a call to g_free() when no longer required.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_base64v(QCryptoHashAlgo alg,
const struct iovec *iov,
size_t niov,
char **base64,
Error **errp);
/**
* qcrypto_hash_base64:
* @alg: the hash algorithm
* @buf: the memory region to hash
* @len: the length of @buf
* @base64: pointer to hold output hash
* @errp: pointer to a NULL-initialized error object
*
* Computes the hash across all the memory region
* @buf of length @len. The @base64 pointer will be
* filled with the base64 encoding of the computed
* hash, which will be terminated by '\0'. The
* memory pointer in @base64 must be released
* with a call to g_free() when no longer required.
*
* Returns: 0 on success, -1 on error
*/
int qcrypto_hash_base64(QCryptoHashAlgo alg,
const char *buf,
size_t len,
char **base64,
Error **errp);
#endif /* QCRYPTO_HASH_H */