boringssl/include/openssl/digest.h
Eric Roman f0e8d537de Update comments in digest.h to consistently mention that digest size and block size are measured in bytes.
Change-Id: Ie75c68132fd501549b2ad5203663f6e99867eed6
Reviewed-on: https://boringssl-review.googlesource.com/5970
Reviewed-by: David Benjamin <davidben@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>
2015-09-24 00:04:12 +00:00

259 lines
11 KiB
C

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.] */
#ifndef OPENSSL_HEADER_DIGEST_H
#define OPENSSL_HEADER_DIGEST_H
#include <openssl/base.h>
#if defined(__cplusplus)
extern "C" {
#endif
/* Digest functions.
*
* An EVP_MD abstracts the details of a specific hash function allowing code to
* deal with the concept of a "hash function" without needing to know exactly
* which hash function it is. */
/* Hash algorithms.
*
* The following functions return |EVP_MD| objects that implement the named hash
* function. */
OPENSSL_EXPORT const EVP_MD *EVP_md4(void);
OPENSSL_EXPORT const EVP_MD *EVP_md5(void);
OPENSSL_EXPORT const EVP_MD *EVP_sha1(void);
OPENSSL_EXPORT const EVP_MD *EVP_sha224(void);
OPENSSL_EXPORT const EVP_MD *EVP_sha256(void);
OPENSSL_EXPORT const EVP_MD *EVP_sha384(void);
OPENSSL_EXPORT const EVP_MD *EVP_sha512(void);
/* EVP_md5_sha1 is a TLS-specific |EVP_MD| which computes the concatenation of
* MD5 and SHA-1, as used in TLS 1.1 and below. */
OPENSSL_EXPORT const EVP_MD *EVP_md5_sha1(void);
/* EVP_get_digestbynid returns an |EVP_MD| for the given NID, or NULL if no
* such digest is known. */
OPENSSL_EXPORT const EVP_MD *EVP_get_digestbynid(int nid);
/* EVP_get_digestbyobj returns an |EVP_MD| for the given |ASN1_OBJECT|, or NULL
* if no such digest is known. */
OPENSSL_EXPORT const EVP_MD *EVP_get_digestbyobj(const ASN1_OBJECT *obj);
/* Digest contexts.
*
* An EVP_MD_CTX represents the state of a specific digest operation in
* progress. */
/* EVP_MD_CTX_init initialises an, already allocated, |EVP_MD_CTX|. */
OPENSSL_EXPORT void EVP_MD_CTX_init(EVP_MD_CTX *ctx);
/* EVP_MD_CTX_create allocates and initialises a fresh |EVP_MD_CTX| and returns
* it, or NULL on allocation failure. */
OPENSSL_EXPORT EVP_MD_CTX *EVP_MD_CTX_create(void);
/* EVP_MD_CTX_cleanup frees any resources owned by |ctx| and resets it to a
* freshly initialised state. It does not free |ctx| itself. It returns one. */
OPENSSL_EXPORT int EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx);
/* EVP_MD_CTX_destroy calls |EVP_MD_CTX_cleanup| and then frees |ctx| itself. */
OPENSSL_EXPORT void EVP_MD_CTX_destroy(EVP_MD_CTX *ctx);
/* EVP_MD_CTX_copy_ex sets |out|, which must already be initialised, to be a
* copy of |in|. It returns one on success and zero on error. */
OPENSSL_EXPORT int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in);
/* Digest operations. */
/* EVP_DigestInit_ex configures |ctx|, which must already have been
* initialised, for a fresh hashing operation using |type|. It returns one on
* success and zero otherwise. */
OPENSSL_EXPORT int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type,
ENGINE *engine);
/* EVP_DigestInit acts like |EVP_DigestInit_ex| except that |ctx| is
* initialised before use. */
OPENSSL_EXPORT int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type);
/* EVP_DigestUpdate hashes |len| bytes from |data| into the hashing operation
* in |ctx|. It returns one. */
OPENSSL_EXPORT int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data,
size_t len);
/* EVP_MAX_MD_SIZE is the largest digest size supported, in bytes.
* Functions that output a digest generally require the buffer have
* at least this much space. */
#define EVP_MAX_MD_SIZE 64 /* SHA-512 is the longest so far. */
/* EVP_DigestFinal_ex finishes the digest in |ctx| and writes the output to
* |md_out|. At most |EVP_MAX_MD_SIZE| bytes are written. If |out_size| is not
* NULL then |*out_size| is set to the number of bytes written. It returns one.
* After this call, the hash cannot be updated or finished again until
* |EVP_DigestInit_ex| is called to start another hashing operation. */
OPENSSL_EXPORT int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, uint8_t *md_out,
unsigned int *out_size);
/* EVP_DigestFinal acts like |EVP_DigestFinal_ex| except that
* |EVP_MD_CTX_cleanup| is called on |ctx| before returning. */
OPENSSL_EXPORT int EVP_DigestFinal(EVP_MD_CTX *ctx, uint8_t *md_out,
unsigned int *out_size);
/* EVP_Digest performs a complete hashing operation in one call. It hashes
* |len| bytes from |data| and writes the digest to |md_out|. At most
* |EVP_MAX_MD_SIZE| bytes are written. If |out_size| is not NULL then
* |*out_size| is set to the number of bytes written. It returns one on success
* and zero otherwise. */
OPENSSL_EXPORT int EVP_Digest(const void *data, size_t len, uint8_t *md_out,
unsigned int *md_out_size, const EVP_MD *type,
ENGINE *impl);
/* Digest function accessors.
*
* These functions allow code to learn details about an abstract hash
* function. */
/* EVP_MD_type returns a NID identifing |md|. (For example, |NID_sha256|.) */
OPENSSL_EXPORT int EVP_MD_type(const EVP_MD *md);
/* EVP_MD_flags returns the flags for |md|, which is a set of |EVP_MD_FLAG_*|
* values, ORed together. */
OPENSSL_EXPORT uint32_t EVP_MD_flags(const EVP_MD *md);
/* EVP_MD_size returns the digest size of |md|, in bytes. */
OPENSSL_EXPORT size_t EVP_MD_size(const EVP_MD *md);
/* EVP_MD_block_size returns the native block-size of |md|, in bytes. */
OPENSSL_EXPORT size_t EVP_MD_block_size(const EVP_MD *md);
/* EVP_MD_FLAG_PKEY_DIGEST indicates the the digest function is used with a
* specific public key in order to verify signatures. (For example,
* EVP_dss1.) */
#define EVP_MD_FLAG_PKEY_DIGEST 1
/* EVP_MD_FLAG_DIGALGID_ABSENT indicates that the parameter type in an X.509
* DigestAlgorithmIdentifier representing this digest function should be
* undefined rather than NULL. */
#define EVP_MD_FLAG_DIGALGID_ABSENT 2
/* Deprecated functions. */
/* EVP_MD_CTX_copy sets |out|, which must /not/ be initialised, to be a copy of
* |in|. It returns one on success and zero on error. */
OPENSSL_EXPORT int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in);
/* EVP_add_digest does nothing and returns one. It exists only for
* compatibility with OpenSSL. */
OPENSSL_EXPORT int EVP_add_digest(const EVP_MD *digest);
/* EVP_get_cipherbyname returns an |EVP_MD| given a human readable name in
* |name|, or NULL if the name is unknown. */
OPENSSL_EXPORT const EVP_MD *EVP_get_digestbyname(const char *);
/* Digest operation accessors. */
/* EVP_MD_CTX_md returns the underlying digest function, or NULL if one has not
* been set. */
OPENSSL_EXPORT const EVP_MD *EVP_MD_CTX_md(const EVP_MD_CTX *ctx);
/* EVP_MD_CTX_size returns the digest size of |ctx|, in bytes. It
* will crash if a digest hasn't been set on |ctx|. */
OPENSSL_EXPORT unsigned EVP_MD_CTX_size(const EVP_MD_CTX *ctx);
/* EVP_MD_CTX_block_size returns the block size of the digest function used by
* |ctx|, in bytes. It will crash if a digest hasn't been set on |ctx|. */
OPENSSL_EXPORT unsigned EVP_MD_CTX_block_size(const EVP_MD_CTX *ctx);
/* EVP_MD_CTX_type returns a NID describing the digest function used by |ctx|.
* (For example, |NID_sha256|.) It will crash if a digest hasn't been set on
* |ctx|. */
OPENSSL_EXPORT int EVP_MD_CTX_type(const EVP_MD_CTX *ctx);
struct evp_md_pctx_ops;
struct env_md_ctx_st {
/* digest is the underlying digest function, or NULL if not set. */
const EVP_MD *digest;
/* md_data points to a block of memory that contains the hash-specific
* context. */
void *md_data;
/* pctx is an opaque (at this layer) pointer to additional context that
* EVP_PKEY functions may store in this object. */
EVP_PKEY_CTX *pctx;
/* pctx_ops, if not NULL, points to a vtable that contains functions to
* manipulate |pctx|. */
const struct evp_md_pctx_ops *pctx_ops;
} /* EVP_MD_CTX */;
#if defined(__cplusplus)
} /* extern C */
#endif
#define DIGEST_R_INPUT_NOT_INITIALIZED 100
#endif /* OPENSSL_HEADER_DIGEST_H */