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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)
63 extern "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 
79 OPENSSL_EXPORT const EVP_MD *EVP_md4(void);
80 OPENSSL_EXPORT const EVP_MD *EVP_md5(void);
81 OPENSSL_EXPORT const EVP_MD *EVP_sha1(void);
82 OPENSSL_EXPORT const EVP_MD *EVP_sha224(void);
83 OPENSSL_EXPORT const EVP_MD *EVP_sha256(void);
84 OPENSSL_EXPORT const EVP_MD *EVP_sha384(void);
85 OPENSSL_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.
89 OPENSSL_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.
93 OPENSSL_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.
97 OPENSSL_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.
107 OPENSSL_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.
112 OPENSSL_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.
116 OPENSSL_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.
119 OPENSSL_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 error.
123 OPENSSL_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|.
126 OPENSSL_EXPORT void EVP_MD_CTX_reset(EVP_MD_CTX *ctx);
127 
128 
129 // Digest operations.
130 
131 // EVP_DigestInit_ex configures |ctx|, which must already have been
132 // initialised, for a fresh hashing operation using |type|. It returns one on
133 // success and zero otherwise.
134 OPENSSL_EXPORT int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type,
135                                      ENGINE *engine);
136 
137 // EVP_DigestInit acts like |EVP_DigestInit_ex| except that |ctx| is
138 // initialised before use.
139 OPENSSL_EXPORT int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type);
140 
141 // EVP_DigestUpdate hashes |len| bytes from |data| into the hashing operation
142 // in |ctx|. It returns one.
143 OPENSSL_EXPORT int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data,
144                                     size_t len);
145 
146 // EVP_MAX_MD_SIZE is the largest digest size supported, in bytes.
147 // Functions that output a digest generally require the buffer have
148 // at least this much space.
149 #define EVP_MAX_MD_SIZE 64  // SHA-512 is the longest so far.
150 
151 // EVP_MAX_MD_BLOCK_SIZE is the largest digest block size supported, in
152 // bytes.
153 #define EVP_MAX_MD_BLOCK_SIZE 128  // SHA-512 is the longest so far.
154 
155 // EVP_DigestFinal_ex finishes the digest in |ctx| and writes the output to
156 // |md_out|. |EVP_MD_CTX_size| bytes are written, which is at most
157 // |EVP_MAX_MD_SIZE|. If |out_size| is not NULL then |*out_size| is set to the
158 // number of bytes written. It returns one. After this call, the hash cannot be
159 // updated or finished again until |EVP_DigestInit_ex| is called to start
160 // another hashing operation.
161 OPENSSL_EXPORT int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, uint8_t *md_out,
162                                       unsigned int *out_size);
163 
164 // EVP_DigestFinal acts like |EVP_DigestFinal_ex| except that
165 // |EVP_MD_CTX_cleanup| is called on |ctx| before returning.
166 OPENSSL_EXPORT int EVP_DigestFinal(EVP_MD_CTX *ctx, uint8_t *md_out,
167                                    unsigned int *out_size);
168 
169 // EVP_Digest performs a complete hashing operation in one call. It hashes |len|
170 // bytes from |data| and writes the digest to |md_out|. |EVP_MD_CTX_size| bytes
171 // are written, which is at most |EVP_MAX_MD_SIZE|. If |out_size| is not NULL
172 // then |*out_size| is set to the number of bytes written. It returns one on
173 // success and zero otherwise.
174 OPENSSL_EXPORT int EVP_Digest(const void *data, size_t len, uint8_t *md_out,
175                               unsigned int *md_out_size, const EVP_MD *type,
176                               ENGINE *impl);
177 
178 
179 // Digest function accessors.
180 //
181 // These functions allow code to learn details about an abstract hash
182 // function.
183 
184 // EVP_MD_type returns a NID identifying |md|. (For example, |NID_sha256|.)
185 OPENSSL_EXPORT int EVP_MD_type(const EVP_MD *md);
186 
187 // EVP_MD_flags returns the flags for |md|, which is a set of |EVP_MD_FLAG_*|
188 // values, ORed together.
189 OPENSSL_EXPORT uint32_t EVP_MD_flags(const EVP_MD *md);
190 
191 // EVP_MD_size returns the digest size of |md|, in bytes.
192 OPENSSL_EXPORT size_t EVP_MD_size(const EVP_MD *md);
193 
194 // EVP_MD_block_size returns the native block-size of |md|, in bytes.
195 OPENSSL_EXPORT size_t EVP_MD_block_size(const EVP_MD *md);
196 
197 // EVP_MD_FLAG_PKEY_DIGEST indicates the the digest function is used with a
198 // specific public key in order to verify signatures. (For example,
199 // EVP_dss1.)
200 #define EVP_MD_FLAG_PKEY_DIGEST 1
201 
202 // EVP_MD_FLAG_DIGALGID_ABSENT indicates that the parameter type in an X.509
203 // DigestAlgorithmIdentifier representing this digest function should be
204 // undefined rather than NULL.
205 #define EVP_MD_FLAG_DIGALGID_ABSENT 2
206 
207 
208 // Digest operation accessors.
209 
210 // EVP_MD_CTX_md returns the underlying digest function, or NULL if one has not
211 // been set.
212 OPENSSL_EXPORT const EVP_MD *EVP_MD_CTX_md(const EVP_MD_CTX *ctx);
213 
214 // EVP_MD_CTX_size returns the digest size of |ctx|, in bytes. It
215 // will crash if a digest hasn't been set on |ctx|.
216 OPENSSL_EXPORT size_t EVP_MD_CTX_size(const EVP_MD_CTX *ctx);
217 
218 // EVP_MD_CTX_block_size returns the block size of the digest function used by
219 // |ctx|, in bytes. It will crash if a digest hasn't been set on |ctx|.
220 OPENSSL_EXPORT size_t EVP_MD_CTX_block_size(const EVP_MD_CTX *ctx);
221 
222 // EVP_MD_CTX_type returns a NID describing the digest function used by |ctx|.
223 // (For example, |NID_sha256|.) It will crash if a digest hasn't been set on
224 // |ctx|.
225 OPENSSL_EXPORT int EVP_MD_CTX_type(const EVP_MD_CTX *ctx);
226 
227 
228 // ASN.1 functions.
229 //
230 // These functions allow code to parse and serialize AlgorithmIdentifiers for
231 // hash functions.
232 
233 // EVP_parse_digest_algorithm parses an AlgorithmIdentifier structure containing
234 // a hash function OID (for example, 2.16.840.1.101.3.4.2.1 is SHA-256) and
235 // advances |cbs|. The parameters field may either be omitted or a NULL. It
236 // returns the digest function or NULL on error.
237 OPENSSL_EXPORT const EVP_MD *EVP_parse_digest_algorithm(CBS *cbs);
238 
239 // EVP_marshal_digest_algorithm marshals |md| as an AlgorithmIdentifier
240 // structure and appends the result to |cbb|. It returns one on success and zero
241 // on error.
242 OPENSSL_EXPORT int EVP_marshal_digest_algorithm(CBB *cbb, const EVP_MD *md);
243 
244 
245 // Deprecated functions.
246 
247 // EVP_MD_CTX_copy sets |out|, which must /not/ be initialised, to be a copy of
248 // |in|. It returns one on success and zero on error.
249 OPENSSL_EXPORT int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in);
250 
251 // EVP_add_digest does nothing and returns one. It exists only for
252 // compatibility with OpenSSL.
253 OPENSSL_EXPORT int EVP_add_digest(const EVP_MD *digest);
254 
255 // EVP_get_digestbyname returns an |EVP_MD| given a human readable name in
256 // |name|, or NULL if the name is unknown.
257 OPENSSL_EXPORT const EVP_MD *EVP_get_digestbyname(const char *);
258 
259 // EVP_dss1 returns the value of EVP_sha1(). This was provided by OpenSSL to
260 // specifiy the original DSA signatures, which were fixed to use SHA-1. Note,
261 // however, that attempting to sign or verify DSA signatures with the EVP
262 // interface will always fail.
263 OPENSSL_EXPORT const EVP_MD *EVP_dss1(void);
264 
265 // EVP_MD_CTX_create calls |EVP_MD_CTX_new|.
266 OPENSSL_EXPORT EVP_MD_CTX *EVP_MD_CTX_create(void);
267 
268 // EVP_MD_CTX_destroy calls |EVP_MD_CTX_free|.
269 OPENSSL_EXPORT void EVP_MD_CTX_destroy(EVP_MD_CTX *ctx);
270 
271 
272 struct evp_md_pctx_ops;
273 
274 struct env_md_ctx_st {
275   // digest is the underlying digest function, or NULL if not set.
276   const EVP_MD *digest;
277   // md_data points to a block of memory that contains the hash-specific
278   // context.
279   void *md_data;
280 
281   // pctx is an opaque (at this layer) pointer to additional context that
282   // EVP_PKEY functions may store in this object.
283   EVP_PKEY_CTX *pctx;
284 
285   // pctx_ops, if not NULL, points to a vtable that contains functions to
286   // manipulate |pctx|.
287   const struct evp_md_pctx_ops *pctx_ops;
288 } /* EVP_MD_CTX */;
289 
290 
291 #if defined(__cplusplus)
292 }  // extern C
293 
294 #if !defined(BORINGSSL_NO_CXX)
295 extern "C++" {
296 
297 namespace bssl {
298 
299 BORINGSSL_MAKE_DELETER(EVP_MD_CTX, EVP_MD_CTX_free)
300 
301 using ScopedEVP_MD_CTX =
302     internal::StackAllocated<EVP_MD_CTX, int, EVP_MD_CTX_init,
303                              EVP_MD_CTX_cleanup>;
304 
305 }  // namespace bssl
306 
307 }  // extern C++
308 #endif
309 
310 #endif
311 
312 #define DIGEST_R_INPUT_NOT_INITIALIZED 100
313 #define DIGEST_R_DECODE_ERROR 101
314 #define DIGEST_R_UNKNOWN_HASH 102
315 
316 #endif  // OPENSSL_HEADER_DIGEST_H
317