digest.h revision e99801b603dea8893dcc61c70b327ef2d00b652c
1/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay@cryptsoft.com). 6 * The implementation was written so as to conform with Netscapes SSL. 7 * 8 * This library is free for commercial and non-commercial use as long as 9 * the following conditions are aheared to. The following conditions 10 * apply to all code found in this distribution, be it the RC4, RSA, 11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 12 * included with this distribution is covered by the same copyright terms 13 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 14 * 15 * Copyright remains Eric Young's, and as such any Copyright notices in 16 * the code are not to be removed. 17 * If this package is used in a product, Eric Young should be given attribution 18 * as the author of the parts of the library used. 19 * This can be in the form of a textual message at program startup or 20 * in documentation (online or textual) provided with the package. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. All advertising materials mentioning features or use of this software 31 * must display the following acknowledgement: 32 * "This product includes cryptographic software written by 33 * Eric Young (eay@cryptsoft.com)" 34 * The word 'cryptographic' can be left out if the rouines from the library 35 * being used are not cryptographic related :-). 36 * 4. If you include any Windows specific code (or a derivative thereof) from 37 * the apps directory (application code) you must include an acknowledgement: 38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * The licence and distribution terms for any publically available version or 53 * derivative of this code cannot be changed. i.e. this code cannot simply be 54 * copied and put under another distribution licence 55 * [including the GNU Public Licence.] */ 56 57#ifndef OPENSSL_HEADER_DIGEST_H 58#define OPENSSL_HEADER_DIGEST_H 59 60#include <openssl/base.h> 61 62#if defined(__cplusplus) 63extern "C" { 64#endif 65 66 67/* Digest functions. 68 * 69 * An EVP_MD abstracts the details of a specific hash function allowing code to 70 * deal with the concept of a "hash function" without needing to know exactly 71 * which hash function it is. */ 72 73 74/* Hash algorithms. 75 * 76 * The following functions return |EVP_MD| objects that implement the named hash 77 * function. */ 78 79OPENSSL_EXPORT const EVP_MD *EVP_md4(void); 80OPENSSL_EXPORT const EVP_MD *EVP_md5(void); 81OPENSSL_EXPORT const EVP_MD *EVP_sha1(void); 82OPENSSL_EXPORT const EVP_MD *EVP_sha224(void); 83OPENSSL_EXPORT const EVP_MD *EVP_sha256(void); 84OPENSSL_EXPORT const EVP_MD *EVP_sha384(void); 85OPENSSL_EXPORT const EVP_MD *EVP_sha512(void); 86 87/* EVP_md5_sha1 is a TLS-specific |EVP_MD| which computes the concatenation of 88 * MD5 and SHA-1, as used in TLS 1.1 and below. */ 89OPENSSL_EXPORT const EVP_MD *EVP_md5_sha1(void); 90 91/* EVP_get_digestbynid returns an |EVP_MD| for the given NID, or NULL if no 92 * such digest is known. */ 93OPENSSL_EXPORT const EVP_MD *EVP_get_digestbynid(int nid); 94 95/* EVP_get_digestbyobj returns an |EVP_MD| for the given |ASN1_OBJECT|, or NULL 96 * if no such digest is known. */ 97OPENSSL_EXPORT const EVP_MD *EVP_get_digestbyobj(const ASN1_OBJECT *obj); 98 99 100/* Digest contexts. 101 * 102 * An EVP_MD_CTX represents the state of a specific digest operation in 103 * progress. */ 104 105/* EVP_MD_CTX_init initialises an, already allocated, |EVP_MD_CTX|. */ 106OPENSSL_EXPORT void EVP_MD_CTX_init(EVP_MD_CTX *ctx); 107 108/* EVP_MD_CTX_create allocates and initialises a fresh |EVP_MD_CTX| and returns 109 * it, or NULL on allocation failure. */ 110OPENSSL_EXPORT EVP_MD_CTX *EVP_MD_CTX_create(void); 111 112/* EVP_MD_CTX_cleanup frees any resources owned by |ctx| and resets it to a 113 * freshly initialised state. It does not free |ctx| itself. It returns one. */ 114OPENSSL_EXPORT int EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx); 115 116/* EVP_MD_CTX_destroy calls |EVP_MD_CTX_cleanup| and then frees |ctx| itself. */ 117OPENSSL_EXPORT void EVP_MD_CTX_destroy(EVP_MD_CTX *ctx); 118 119/* EVP_MD_CTX_copy_ex sets |out|, which must already be initialised, to be a 120 * copy of |in|. It returns one on success and zero on error. */ 121OPENSSL_EXPORT int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in); 122 123 124/* Digest operations. */ 125 126/* EVP_DigestInit_ex configures |ctx|, which must already have been 127 * initialised, for a fresh hashing operation using |type|. It returns one on 128 * success and zero otherwise. */ 129OPENSSL_EXPORT int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, 130 ENGINE *engine); 131 132/* EVP_DigestInit acts like |EVP_DigestInit_ex| except that |ctx| is 133 * initialised before use. */ 134OPENSSL_EXPORT int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type); 135 136/* EVP_DigestUpdate hashes |len| bytes from |data| into the hashing operation 137 * in |ctx|. It returns one. */ 138OPENSSL_EXPORT int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data, 139 size_t len); 140 141/* EVP_MAX_MD_SIZE is the largest digest size supported, in bytes. 142 * Functions that output a digest generally require the buffer have 143 * at least this much space. */ 144#define EVP_MAX_MD_SIZE 64 /* SHA-512 is the longest so far. */ 145 146/* EVP_DigestFinal_ex finishes the digest in |ctx| and writes the output to 147 * |md_out|. At most |EVP_MAX_MD_SIZE| bytes are written. If |out_size| is not 148 * NULL then |*out_size| is set to the number of bytes written. It returns one. 149 * After this call, the hash cannot be updated or finished again until 150 * |EVP_DigestInit_ex| is called to start another hashing operation. */ 151OPENSSL_EXPORT int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, uint8_t *md_out, 152 unsigned int *out_size); 153 154/* EVP_DigestFinal acts like |EVP_DigestFinal_ex| except that 155 * |EVP_MD_CTX_cleanup| is called on |ctx| before returning. */ 156OPENSSL_EXPORT int EVP_DigestFinal(EVP_MD_CTX *ctx, uint8_t *md_out, 157 unsigned int *out_size); 158 159/* EVP_Digest performs a complete hashing operation in one call. It hashes 160 * |len| bytes from |data| and writes the digest to |md_out|. At most 161 * |EVP_MAX_MD_SIZE| bytes are written. If |out_size| is not NULL then 162 * |*out_size| is set to the number of bytes written. It returns one on success 163 * and zero otherwise. */ 164OPENSSL_EXPORT int EVP_Digest(const void *data, size_t len, uint8_t *md_out, 165 unsigned int *md_out_size, const EVP_MD *type, 166 ENGINE *impl); 167 168 169/* Digest function accessors. 170 * 171 * These functions allow code to learn details about an abstract hash 172 * function. */ 173 174/* EVP_MD_type returns a NID identifing |md|. (For example, |NID_sha256|.) */ 175OPENSSL_EXPORT int EVP_MD_type(const EVP_MD *md); 176 177/* EVP_MD_flags returns the flags for |md|, which is a set of |EVP_MD_FLAG_*| 178 * values, ORed together. */ 179OPENSSL_EXPORT uint32_t EVP_MD_flags(const EVP_MD *md); 180 181/* EVP_MD_size returns the digest size of |md|, in bytes. */ 182OPENSSL_EXPORT size_t EVP_MD_size(const EVP_MD *md); 183 184/* EVP_MD_block_size returns the native block-size of |md|, in bytes. */ 185OPENSSL_EXPORT size_t EVP_MD_block_size(const EVP_MD *md); 186 187/* EVP_MD_FLAG_PKEY_DIGEST indicates the the digest function is used with a 188 * specific public key in order to verify signatures. (For example, 189 * EVP_dss1.) */ 190#define EVP_MD_FLAG_PKEY_DIGEST 1 191 192/* EVP_MD_FLAG_DIGALGID_ABSENT indicates that the parameter type in an X.509 193 * DigestAlgorithmIdentifier representing this digest function should be 194 * undefined rather than NULL. */ 195#define EVP_MD_FLAG_DIGALGID_ABSENT 2 196 197 198/* Deprecated functions. */ 199 200/* EVP_MD_CTX_copy sets |out|, which must /not/ be initialised, to be a copy of 201 * |in|. It returns one on success and zero on error. */ 202OPENSSL_EXPORT int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in); 203 204/* EVP_add_digest does nothing and returns one. It exists only for 205 * compatibility with OpenSSL. */ 206OPENSSL_EXPORT int EVP_add_digest(const EVP_MD *digest); 207 208/* EVP_get_digestbyname returns an |EVP_MD| given a human readable name in 209 * |name|, or NULL if the name is unknown. */ 210OPENSSL_EXPORT const EVP_MD *EVP_get_digestbyname(const char *); 211 212 213/* Digest operation accessors. */ 214 215/* EVP_MD_CTX_md returns the underlying digest function, or NULL if one has not 216 * been set. */ 217OPENSSL_EXPORT const EVP_MD *EVP_MD_CTX_md(const EVP_MD_CTX *ctx); 218 219/* EVP_MD_CTX_size returns the digest size of |ctx|, in bytes. It 220 * will crash if a digest hasn't been set on |ctx|. */ 221OPENSSL_EXPORT unsigned EVP_MD_CTX_size(const EVP_MD_CTX *ctx); 222 223/* EVP_MD_CTX_block_size returns the block size of the digest function used by 224 * |ctx|, in bytes. It will crash if a digest hasn't been set on |ctx|. */ 225OPENSSL_EXPORT unsigned EVP_MD_CTX_block_size(const EVP_MD_CTX *ctx); 226 227/* EVP_MD_CTX_type returns a NID describing the digest function used by |ctx|. 228 * (For example, |NID_sha256|.) It will crash if a digest hasn't been set on 229 * |ctx|. */ 230OPENSSL_EXPORT int EVP_MD_CTX_type(const EVP_MD_CTX *ctx); 231 232 233struct evp_md_pctx_ops; 234 235struct env_md_ctx_st { 236 /* digest is the underlying digest function, or NULL if not set. */ 237 const EVP_MD *digest; 238 /* md_data points to a block of memory that contains the hash-specific 239 * context. */ 240 void *md_data; 241 242 /* pctx is an opaque (at this layer) pointer to additional context that 243 * EVP_PKEY functions may store in this object. */ 244 EVP_PKEY_CTX *pctx; 245 246 /* pctx_ops, if not NULL, points to a vtable that contains functions to 247 * manipulate |pctx|. */ 248 const struct evp_md_pctx_ops *pctx_ops; 249} /* EVP_MD_CTX */; 250 251 252#if defined(__cplusplus) 253} /* extern C */ 254#endif 255 256#define DIGEST_R_INPUT_NOT_INITIALIZED 100 257 258#endif /* OPENSSL_HEADER_DIGEST_H */ 259