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|. This is the
106// same as setting the structure to zero.
107OPENSSL_EXPORT void EVP_MD_CTX_init(EVP_MD_CTX *ctx);
108
109// EVP_MD_CTX_new allocates and initialises a fresh |EVP_MD_CTX| and returns
110// it, or NULL on allocation failure. The caller must use |EVP_MD_CTX_free| to
111// release the resulting object.
112OPENSSL_EXPORT EVP_MD_CTX *EVP_MD_CTX_new(void);
113
114// EVP_MD_CTX_cleanup frees any resources owned by |ctx| and resets it to a
115// freshly initialised state. It does not free |ctx| itself. It returns one.
116OPENSSL_EXPORT int EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx);
117
118// EVP_MD_CTX_free calls |EVP_MD_CTX_cleanup| and then frees |ctx| itself.
119OPENSSL_EXPORT void EVP_MD_CTX_free(EVP_MD_CTX *ctx);
120
121// EVP_MD_CTX_copy_ex sets |out|, which must already be initialised, to be a
122// copy of |in|. It returns one on success and zero on allocation failure.
123OPENSSL_EXPORT int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in);
124
125// EVP_MD_CTX_reset calls |EVP_MD_CTX_cleanup| followed by |EVP_MD_CTX_init|. It
126// returns one.
127OPENSSL_EXPORT int EVP_MD_CTX_reset(EVP_MD_CTX *ctx);
128
129
130// Digest operations.
131
132// EVP_DigestInit_ex configures |ctx|, which must already have been
133// initialised, for a fresh hashing operation using |type|. It returns one on
134// success and zero on allocation failure.
135OPENSSL_EXPORT int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type,
136 ENGINE *engine);
137
138// EVP_DigestInit acts like |EVP_DigestInit_ex| except that |ctx| is
139// initialised before use.
140OPENSSL_EXPORT int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type);
141
142// EVP_DigestUpdate hashes |len| bytes from |data| into the hashing operation
143// in |ctx|. It returns one.
144OPENSSL_EXPORT int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data,
145 size_t len);
146
147// EVP_MAX_MD_SIZE is the largest digest size supported, in bytes.
148// Functions that output a digest generally require the buffer have
149// at least this much space.
150#define EVP_MAX_MD_SIZE 64 // SHA-512 is the longest so far.
151
152// EVP_MAX_MD_BLOCK_SIZE is the largest digest block size supported, in
153// bytes.
154#define EVP_MAX_MD_BLOCK_SIZE 128 // SHA-512 is the longest so far.
155
156// EVP_DigestFinal_ex finishes the digest in |ctx| and writes the output to
157// |md_out|. |EVP_MD_CTX_size| bytes are written, which is at most
158// |EVP_MAX_MD_SIZE|. If |out_size| is not NULL then |*out_size| is set to the
159// number of bytes written. It returns one. After this call, the hash cannot be
160// updated or finished again until |EVP_DigestInit_ex| is called to start
161// another hashing operation.
162OPENSSL_EXPORT int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, uint8_t *md_out,
163 unsigned int *out_size);
164
165// EVP_DigestFinal acts like |EVP_DigestFinal_ex| except that
166// |EVP_MD_CTX_cleanup| is called on |ctx| before returning.
167OPENSSL_EXPORT int EVP_DigestFinal(EVP_MD_CTX *ctx, uint8_t *md_out,
168 unsigned int *out_size);
169
170// EVP_Digest performs a complete hashing operation in one call. It hashes |len|
171// bytes from |data| and writes the digest to |md_out|. |EVP_MD_CTX_size| bytes
172// are written, which is at most |EVP_MAX_MD_SIZE|. If |out_size| is not NULL
173// then |*out_size| is set to the number of bytes written. It returns one on
174// success and zero otherwise.
175OPENSSL_EXPORT int EVP_Digest(const void *data, size_t len, uint8_t *md_out,
176 unsigned int *md_out_size, const EVP_MD *type,
177 ENGINE *impl);
178
179
180// Digest function accessors.
181//
182// These functions allow code to learn details about an abstract hash
183// function.
184
185// EVP_MD_type returns a NID identifying |md|. (For example, |NID_sha256|.)
186OPENSSL_EXPORT int EVP_MD_type(const EVP_MD *md);
187
188// EVP_MD_flags returns the flags for |md|, which is a set of |EVP_MD_FLAG_*|
189// values, ORed together.
190OPENSSL_EXPORT uint32_t EVP_MD_flags(const EVP_MD *md);
191
192// EVP_MD_size returns the digest size of |md|, in bytes.
193OPENSSL_EXPORT size_t EVP_MD_size(const EVP_MD *md);
194
195// EVP_MD_block_size returns the native block-size of |md|, in bytes.
196OPENSSL_EXPORT size_t EVP_MD_block_size(const EVP_MD *md);
197
198// EVP_MD_FLAG_PKEY_DIGEST indicates the the digest function is used with a
199// specific public key in order to verify signatures. (For example,
200// EVP_dss1.)
201#define EVP_MD_FLAG_PKEY_DIGEST 1
202
203// EVP_MD_FLAG_DIGALGID_ABSENT indicates that the parameter type in an X.509
204// DigestAlgorithmIdentifier representing this digest function should be
205// undefined rather than NULL.
206#define EVP_MD_FLAG_DIGALGID_ABSENT 2
207
208
209// Digest operation accessors.
210
211// EVP_MD_CTX_md returns the underlying digest function, or NULL if one has not
212// been set.
213OPENSSL_EXPORT const EVP_MD *EVP_MD_CTX_md(const EVP_MD_CTX *ctx);
214
215// EVP_MD_CTX_size returns the digest size of |ctx|, in bytes. It
216// will crash if a digest hasn't been set on |ctx|.
217OPENSSL_EXPORT size_t EVP_MD_CTX_size(const EVP_MD_CTX *ctx);
218
219// EVP_MD_CTX_block_size returns the block size of the digest function used by
220// |ctx|, in bytes. It will crash if a digest hasn't been set on |ctx|.
221OPENSSL_EXPORT size_t EVP_MD_CTX_block_size(const EVP_MD_CTX *ctx);
222
223// EVP_MD_CTX_type returns a NID describing the digest function used by |ctx|.
224// (For example, |NID_sha256|.) It will crash if a digest hasn't been set on
225// |ctx|.
226OPENSSL_EXPORT int EVP_MD_CTX_type(const EVP_MD_CTX *ctx);
227
228
229// ASN.1 functions.
230//
231// These functions allow code to parse and serialize AlgorithmIdentifiers for
232// hash functions.
233
234// EVP_parse_digest_algorithm parses an AlgorithmIdentifier structure containing
235// a hash function OID (for example, 2.16.840.1.101.3.4.2.1 is SHA-256) and
236// advances |cbs|. The parameters field may either be omitted or a NULL. It
237// returns the digest function or NULL on error.
238OPENSSL_EXPORT const EVP_MD *EVP_parse_digest_algorithm(CBS *cbs);
239
240// EVP_marshal_digest_algorithm marshals |md| as an AlgorithmIdentifier
241// structure and appends the result to |cbb|. It returns one on success and zero
242// on error.
243OPENSSL_EXPORT int EVP_marshal_digest_algorithm(CBB *cbb, const EVP_MD *md);
244
245
246// Deprecated functions.
247
248// EVP_MD_CTX_copy sets |out|, which must /not/ be initialised, to be a copy of
249// |in|. It returns one on success and zero on error.
250OPENSSL_EXPORT int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in);
251
252// EVP_add_digest does nothing and returns one. It exists only for
253// compatibility with OpenSSL.
254OPENSSL_EXPORT int EVP_add_digest(const EVP_MD *digest);
255
256// EVP_get_digestbyname returns an |EVP_MD| given a human readable name in
257// |name|, or NULL if the name is unknown.
258OPENSSL_EXPORT const EVP_MD *EVP_get_digestbyname(const char *);
259
260// EVP_dss1 returns the value of EVP_sha1(). This was provided by OpenSSL to
261// specifiy the original DSA signatures, which were fixed to use SHA-1. Note,
262// however, that attempting to sign or verify DSA signatures with the EVP
263// interface will always fail.
264OPENSSL_EXPORT const EVP_MD *EVP_dss1(void);
265
266// EVP_MD_CTX_create calls |EVP_MD_CTX_new|.
267OPENSSL_EXPORT EVP_MD_CTX *EVP_MD_CTX_create(void);
268
269// EVP_MD_CTX_destroy calls |EVP_MD_CTX_free|.
270OPENSSL_EXPORT void EVP_MD_CTX_destroy(EVP_MD_CTX *ctx);
271
272// EVP_DigestFinalXOF returns zero and adds an error to the error queue.
273// BoringSSL does not support any XOF digests.
274OPENSSL_EXPORT int EVP_DigestFinalXOF(EVP_MD_CTX *ctx, uint8_t *out,
275 size_t len);
276
277
278struct evp_md_pctx_ops;
279
280struct env_md_ctx_st {
281 // digest is the underlying digest function, or NULL if not set.
282 const EVP_MD *digest;
283 // md_data points to a block of memory that contains the hash-specific
284 // context.
285 void *md_data;
286
287 // pctx is an opaque (at this layer) pointer to additional context that
288 // EVP_PKEY functions may store in this object.
289 EVP_PKEY_CTX *pctx;
290
291 // pctx_ops, if not NULL, points to a vtable that contains functions to
292 // manipulate |pctx|.
293 const struct evp_md_pctx_ops *pctx_ops;
294} /* EVP_MD_CTX */;
295
296
297#if defined(__cplusplus)
298} // extern C
299
300#if !defined(BORINGSSL_NO_CXX)
301extern "C++" {
302
303BSSL_NAMESPACE_BEGIN
304
305BORINGSSL_MAKE_DELETER(EVP_MD_CTX, EVP_MD_CTX_free)
306
307using ScopedEVP_MD_CTX =
308 internal::StackAllocated<EVP_MD_CTX, int, EVP_MD_CTX_init,
309 EVP_MD_CTX_cleanup>;
310
311BSSL_NAMESPACE_END
312
313} // extern C++
314#endif
315
316#endif
317
318#define DIGEST_R_INPUT_NOT_INITIALIZED 100
319#define DIGEST_R_DECODE_ERROR 101
320#define DIGEST_R_UNKNOWN_HASH 102
321
322#endif // OPENSSL_HEADER_DIGEST_H
323