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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_EVP_H
58 #define OPENSSL_HEADER_EVP_H
59 
60 #include <openssl/base.h>
61 
62 #include <openssl/thread.h>
63 
64 /* OpenSSL included digest and cipher functions in this header so we include
65  * them for users that still expect that.
66  *
67  * TODO(fork): clean up callers so that they include what they use. */
68 #include <openssl/aead.h>
69 #include <openssl/base64.h>
70 #include <openssl/cipher.h>
71 #include <openssl/digest.h>
72 #include <openssl/nid.h>
73 
74 #if defined(__cplusplus)
75 extern "C" {
76 #endif
77 
78 
79 /* EVP abstracts over public/private key algorithms. */
80 
81 
82 /* Public key objects. */
83 
84 /* EVP_PKEY_new creates a new, empty public-key object and returns it or NULL
85  * on allocation failure. */
86 OPENSSL_EXPORT EVP_PKEY *EVP_PKEY_new(void);
87 
88 /* EVP_PKEY_free frees all data referenced by |pkey| and then frees |pkey|
89  * itself. */
90 OPENSSL_EXPORT void EVP_PKEY_free(EVP_PKEY *pkey);
91 
92 /* EVP_PKEY_up_ref increments the reference count of |pkey| and returns one. */
93 OPENSSL_EXPORT int EVP_PKEY_up_ref(EVP_PKEY *pkey);
94 
95 /* EVP_PKEY_is_opaque returns one if |pkey| is opaque. Opaque keys are backed by
96  * custom implementations which do not expose key material and parameters. It is
97  * an error to attempt to duplicate, export, or compare an opaque key. */
98 OPENSSL_EXPORT int EVP_PKEY_is_opaque(const EVP_PKEY *pkey);
99 
100 /* EVP_PKEY_cmp compares |a| and |b| and returns one if they are equal, zero if
101  * not and a negative number on error.
102  *
103  * WARNING: this differs from the traditional return value of a "cmp"
104  * function. */
105 OPENSSL_EXPORT int EVP_PKEY_cmp(const EVP_PKEY *a, const EVP_PKEY *b);
106 
107 /* EVP_PKEY_copy_parameters sets the parameters of |to| to equal the parameters
108  * of |from|. It returns one on success and zero on error. */
109 OPENSSL_EXPORT int EVP_PKEY_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from);
110 
111 /* EVP_PKEY_missing_parameters returns one if |pkey| is missing needed
112  * parameters or zero if not, or if the algorithm doesn't take parameters. */
113 OPENSSL_EXPORT int EVP_PKEY_missing_parameters(const EVP_PKEY *pkey);
114 
115 /* EVP_PKEY_size returns the maximum size, in bytes, of a signature signed by
116  * |pkey|. For an RSA key, this returns the number of bytes needed to represent
117  * the modulus. For an EC key, this returns the maximum size of a DER-encoded
118  * ECDSA signature. */
119 OPENSSL_EXPORT int EVP_PKEY_size(const EVP_PKEY *pkey);
120 
121 /* EVP_PKEY_bits returns the "size", in bits, of |pkey|. For an RSA key, this
122  * returns the bit length of the modulus. For an EC key, this returns the bit
123  * length of the group order. */
124 OPENSSL_EXPORT int EVP_PKEY_bits(EVP_PKEY *pkey);
125 
126 /* EVP_PKEY_id returns the type of |pkey|, which is one of the |EVP_PKEY_*|
127  * values. */
128 OPENSSL_EXPORT int EVP_PKEY_id(const EVP_PKEY *pkey);
129 
130 /* EVP_PKEY_type returns |nid| if |nid| is a known key type and |NID_undef|
131  * otherwise. */
132 OPENSSL_EXPORT int EVP_PKEY_type(int nid);
133 
134 
135 /* Getting and setting concrete public key types.
136  *
137  * The following functions get and set the underlying public key in an
138  * |EVP_PKEY| object. The |set1| functions take an additional reference to the
139  * underlying key and return one on success or zero on error. The |assign|
140  * functions adopt the caller's reference. The |get1| functions return a fresh
141  * reference to the underlying object or NULL if |pkey| is not of the correct
142  * type. The |get0| functions behave the same but return a non-owning
143  * pointer. */
144 
145 OPENSSL_EXPORT int EVP_PKEY_set1_RSA(EVP_PKEY *pkey, RSA *key);
146 OPENSSL_EXPORT int EVP_PKEY_assign_RSA(EVP_PKEY *pkey, RSA *key);
147 OPENSSL_EXPORT RSA *EVP_PKEY_get0_RSA(EVP_PKEY *pkey);
148 OPENSSL_EXPORT RSA *EVP_PKEY_get1_RSA(EVP_PKEY *pkey);
149 
150 OPENSSL_EXPORT int EVP_PKEY_set1_DSA(EVP_PKEY *pkey, DSA *key);
151 OPENSSL_EXPORT int EVP_PKEY_assign_DSA(EVP_PKEY *pkey, DSA *key);
152 OPENSSL_EXPORT DSA *EVP_PKEY_get0_DSA(EVP_PKEY *pkey);
153 OPENSSL_EXPORT DSA *EVP_PKEY_get1_DSA(EVP_PKEY *pkey);
154 
155 OPENSSL_EXPORT int EVP_PKEY_set1_EC_KEY(EVP_PKEY *pkey, EC_KEY *key);
156 OPENSSL_EXPORT int EVP_PKEY_assign_EC_KEY(EVP_PKEY *pkey, EC_KEY *key);
157 OPENSSL_EXPORT EC_KEY *EVP_PKEY_get0_EC_KEY(EVP_PKEY *pkey);
158 OPENSSL_EXPORT EC_KEY *EVP_PKEY_get1_EC_KEY(EVP_PKEY *pkey);
159 
160 /* EVP_PKEY_new_ed25519_public returns a newly allocated |EVP_PKEY| wrapping an
161  * Ed25519 public key, or NULL on allocation error. */
162 OPENSSL_EXPORT EVP_PKEY *EVP_PKEY_new_ed25519_public(
163     const uint8_t public_key[32]);
164 
165 /* EVP_PKEY_new_ed25519_private returns a newly allocated |EVP_PKEY| wrapping an
166  * Ed25519 private key, or NULL on allocation error. */
167 OPENSSL_EXPORT EVP_PKEY *EVP_PKEY_new_ed25519_private(
168     const uint8_t private_key[64]);
169 
170 #define EVP_PKEY_NONE NID_undef
171 #define EVP_PKEY_RSA NID_rsaEncryption
172 #define EVP_PKEY_DSA NID_dsa
173 #define EVP_PKEY_EC NID_X9_62_id_ecPublicKey
174 #define EVP_PKEY_ED25519 NID_ED25519
175 
176 /* EVP_PKEY_assign sets the underlying key of |pkey| to |key|, which must be of
177  * the given type. The |type| argument should be one of the |EVP_PKEY_*|
178  * values. */
179 OPENSSL_EXPORT int EVP_PKEY_assign(EVP_PKEY *pkey, int type, void *key);
180 
181 /* EVP_PKEY_set_type sets the type of |pkey| to |type|, which should be one of
182  * the |EVP_PKEY_*| values. It returns one if successful or zero otherwise. If
183  * |pkey| is NULL, it simply reports whether the type is known. */
184 OPENSSL_EXPORT int EVP_PKEY_set_type(EVP_PKEY *pkey, int type);
185 
186 /* EVP_PKEY_cmp_parameters compares the parameters of |a| and |b|. It returns
187  * one if they match, zero if not, or a negative number of on error.
188  *
189  * WARNING: the return value differs from the usual return value convention. */
190 OPENSSL_EXPORT int EVP_PKEY_cmp_parameters(const EVP_PKEY *a,
191                                            const EVP_PKEY *b);
192 
193 
194 /* ASN.1 functions */
195 
196 /* EVP_parse_public_key decodes a DER-encoded SubjectPublicKeyInfo structure
197  * (RFC 5280) from |cbs| and advances |cbs|. It returns a newly-allocated
198  * |EVP_PKEY| or NULL on error.
199  *
200  * The caller must check the type of the parsed public key to ensure it is
201  * suitable and validate other desired key properties such as RSA modulus size
202  * or EC curve. */
203 OPENSSL_EXPORT EVP_PKEY *EVP_parse_public_key(CBS *cbs);
204 
205 /* EVP_marshal_public_key marshals |key| as a DER-encoded SubjectPublicKeyInfo
206  * structure (RFC 5280) and appends the result to |cbb|. It returns one on
207  * success and zero on error. */
208 OPENSSL_EXPORT int EVP_marshal_public_key(CBB *cbb, const EVP_PKEY *key);
209 
210 /* EVP_parse_private_key decodes a DER-encoded PrivateKeyInfo structure (RFC
211  * 5208) from |cbs| and advances |cbs|. It returns a newly-allocated |EVP_PKEY|
212  * or NULL on error.
213  *
214  * The caller must check the type of the parsed private key to ensure it is
215  * suitable and validate other desired key properties such as RSA modulus size
216  * or EC curve.
217  *
218  * A PrivateKeyInfo ends with an optional set of attributes. These are not
219  * processed and so this function will silently ignore any trailing data in the
220  * structure. */
221 OPENSSL_EXPORT EVP_PKEY *EVP_parse_private_key(CBS *cbs);
222 
223 /* EVP_marshal_private_key marshals |key| as a DER-encoded PrivateKeyInfo
224  * structure (RFC 5208) and appends the result to |cbb|. It returns one on
225  * success and zero on error. */
226 OPENSSL_EXPORT int EVP_marshal_private_key(CBB *cbb, const EVP_PKEY *key);
227 
228 /* EVP_set_buggy_rsa_parser configures whether |RSA_parse_public_key_buggy| is
229  * used by |EVP_parse_public_key|. By default, it is used. */
230 OPENSSL_EXPORT void EVP_set_buggy_rsa_parser(int buggy);
231 
232 
233 /* Signing */
234 
235 /* EVP_DigestSignInit sets up |ctx| for a signing operation with |type| and
236  * |pkey|. The |ctx| argument must have been initialised with
237  * |EVP_MD_CTX_init|. If |pctx| is not NULL, the |EVP_PKEY_CTX| of the signing
238  * operation will be written to |*pctx|; this can be used to set alternative
239  * signing options.
240  *
241  * For single-shot signing algorithms which do not use a pre-hash, such as
242  * Ed25519, |type| should be NULL. The |EVP_MD_CTX| itself is unused but is
243  * present so the API is uniform. See |EVP_DigestSign|.
244  *
245  * It returns one on success, or zero on error. */
246 OPENSSL_EXPORT int EVP_DigestSignInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,
247                                       const EVP_MD *type, ENGINE *e,
248                                       EVP_PKEY *pkey);
249 
250 /* EVP_DigestSignUpdate appends |len| bytes from |data| to the data which will
251  * be signed in |EVP_DigestSignFinal|. It returns one.
252  *
253  * This function performs a streaming signing operation and will fail for
254  * signature algorithms which do not support this. Use |EVP_DigestSign| for a
255  * single-shot operation. */
256 OPENSSL_EXPORT int EVP_DigestSignUpdate(EVP_MD_CTX *ctx, const void *data,
257                                         size_t len);
258 
259 /* EVP_DigestSignFinal signs the data that has been included by one or more
260  * calls to |EVP_DigestSignUpdate|. If |out_sig| is NULL then |*out_sig_len| is
261  * set to the maximum number of output bytes. Otherwise, on entry,
262  * |*out_sig_len| must contain the length of the |out_sig| buffer. If the call
263  * is successful, the signature is written to |out_sig| and |*out_sig_len| is
264  * set to its length.
265  *
266  * This function performs a streaming signing operation and will fail for
267  * signature algorithms which do not support this. Use |EVP_DigestSign| for a
268  * single-shot operation.
269  *
270  * It returns one on success, or zero on error. */
271 OPENSSL_EXPORT int EVP_DigestSignFinal(EVP_MD_CTX *ctx, uint8_t *out_sig,
272                                        size_t *out_sig_len);
273 
274 /* EVP_DigestSign signs |data_len| bytes from |data| using |ctx|. If |out_sig|
275  * is NULL then |*out_sig_len| is set to the maximum number of output
276  * bytes. Otherwise, on entry, |*out_sig_len| must contain the length of the
277  * |out_sig| buffer. If the call is successful, the signature is written to
278  * |out_sig| and |*out_sig_len| is set to its length.
279  *
280  * It returns one on success and zero on error. */
281 OPENSSL_EXPORT int EVP_DigestSign(EVP_MD_CTX *ctx, uint8_t *out_sig,
282                                   size_t *out_sig_len, const uint8_t *data,
283                                   size_t data_len);
284 
285 
286 /* Verifying */
287 
288 /* EVP_DigestVerifyInit sets up |ctx| for a signature verification operation
289  * with |type| and |pkey|. The |ctx| argument must have been initialised with
290  * |EVP_MD_CTX_init|. If |pctx| is not NULL, the |EVP_PKEY_CTX| of the signing
291  * operation will be written to |*pctx|; this can be used to set alternative
292  * signing options.
293  *
294  * For single-shot signing algorithms which do not use a pre-hash, such as
295  * Ed25519, |type| should be NULL. The |EVP_MD_CTX| itself is unused but is
296  * present so the API is uniform. See |EVP_DigestVerify|.
297  *
298  * It returns one on success, or zero on error. */
299 OPENSSL_EXPORT int EVP_DigestVerifyInit(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx,
300                                         const EVP_MD *type, ENGINE *e,
301                                         EVP_PKEY *pkey);
302 
303 /* EVP_DigestVerifyUpdate appends |len| bytes from |data| to the data which
304  * will be verified by |EVP_DigestVerifyFinal|. It returns one.
305  *
306  * This function performs streaming signature verification and will fail for
307  * signature algorithms which do not support this. Use |EVP_PKEY_verify_message|
308  * for a single-shot verification. */
309 OPENSSL_EXPORT int EVP_DigestVerifyUpdate(EVP_MD_CTX *ctx, const void *data,
310                                           size_t len);
311 
312 /* EVP_DigestVerifyFinal verifies that |sig_len| bytes of |sig| are a valid
313  * signature for the data that has been included by one or more calls to
314  * |EVP_DigestVerifyUpdate|. It returns one on success and zero otherwise.
315  *
316  * This function performs streaming signature verification and will fail for
317  * signature algorithms which do not support this. Use |EVP_PKEY_verify_message|
318  * for a single-shot verification. */
319 OPENSSL_EXPORT int EVP_DigestVerifyFinal(EVP_MD_CTX *ctx, const uint8_t *sig,
320                                          size_t sig_len);
321 
322 /* EVP_DigestVerify verifies that |sig_len| bytes from |sig| are a valid
323  * signature for |data|. It returns one on success or zero on error. */
324 OPENSSL_EXPORT int EVP_DigestVerify(EVP_MD_CTX *ctx, const uint8_t *sig,
325                                     size_t sig_len, const uint8_t *data,
326                                     size_t len);
327 
328 
329 /* Signing (old functions) */
330 
331 /* EVP_SignInit_ex configures |ctx|, which must already have been initialised,
332  * for a fresh signing operation using the hash function |type|. It returns one
333  * on success and zero otherwise.
334  *
335  * (In order to initialise |ctx|, either obtain it initialised with
336  * |EVP_MD_CTX_create|, or use |EVP_MD_CTX_init|.) */
337 OPENSSL_EXPORT int EVP_SignInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type,
338                                    ENGINE *impl);
339 
340 /* EVP_SignInit is a deprecated version of |EVP_SignInit_ex|.
341  *
342  * TODO(fork): remove. */
343 OPENSSL_EXPORT int EVP_SignInit(EVP_MD_CTX *ctx, const EVP_MD *type);
344 
345 /* EVP_SignUpdate appends |len| bytes from |data| to the data which will be
346  * signed in |EVP_SignFinal|. */
347 OPENSSL_EXPORT int EVP_SignUpdate(EVP_MD_CTX *ctx, const void *data,
348                                   size_t len);
349 
350 /* EVP_SignFinal signs the data that has been included by one or more calls to
351  * |EVP_SignUpdate|, using the key |pkey|, and writes it to |sig|. On entry,
352  * |sig| must point to at least |EVP_PKEY_size(pkey)| bytes of space. The
353  * actual size of the signature is written to |*out_sig_len|.
354  *
355  * It returns one on success and zero otherwise.
356  *
357  * It does not modify |ctx|, thus it's possible to continue to use |ctx| in
358  * order to sign a longer message. */
359 OPENSSL_EXPORT int EVP_SignFinal(const EVP_MD_CTX *ctx, uint8_t *sig,
360                                  unsigned int *out_sig_len, EVP_PKEY *pkey);
361 
362 
363 /* Verifying (old functions) */
364 
365 /* EVP_VerifyInit_ex configures |ctx|, which must already have been
366  * initialised, for a fresh signature verification operation using the hash
367  * function |type|. It returns one on success and zero otherwise.
368  *
369  * (In order to initialise |ctx|, either obtain it initialised with
370  * |EVP_MD_CTX_create|, or use |EVP_MD_CTX_init|.) */
371 OPENSSL_EXPORT int EVP_VerifyInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type,
372                                      ENGINE *impl);
373 
374 /* EVP_VerifyInit is a deprecated version of |EVP_VerifyInit_ex|.
375  *
376  * TODO(fork): remove. */
377 OPENSSL_EXPORT int EVP_VerifyInit(EVP_MD_CTX *ctx, const EVP_MD *type);
378 
379 /* EVP_VerifyUpdate appends |len| bytes from |data| to the data which will be
380  * signed in |EVP_VerifyFinal|. */
381 OPENSSL_EXPORT int EVP_VerifyUpdate(EVP_MD_CTX *ctx, const void *data,
382                                     size_t len);
383 
384 /* EVP_VerifyFinal verifies that |sig_len| bytes of |sig| are a valid
385  * signature, by |pkey|, for the data that has been included by one or more
386  * calls to |EVP_VerifyUpdate|.
387  *
388  * It returns one on success and zero otherwise.
389  *
390  * It does not modify |ctx|, thus it's possible to continue to use |ctx| in
391  * order to sign a longer message. */
392 OPENSSL_EXPORT int EVP_VerifyFinal(EVP_MD_CTX *ctx, const uint8_t *sig,
393                                    size_t sig_len, EVP_PKEY *pkey);
394 
395 
396 /* Printing */
397 
398 /* EVP_PKEY_print_public prints a textual representation of the public key in
399  * |pkey| to |out|. Returns one on success or zero otherwise. */
400 OPENSSL_EXPORT int EVP_PKEY_print_public(BIO *out, const EVP_PKEY *pkey,
401                                          int indent, ASN1_PCTX *pctx);
402 
403 /* EVP_PKEY_print_private prints a textual representation of the private key in
404  * |pkey| to |out|. Returns one on success or zero otherwise. */
405 OPENSSL_EXPORT int EVP_PKEY_print_private(BIO *out, const EVP_PKEY *pkey,
406                                           int indent, ASN1_PCTX *pctx);
407 
408 /* EVP_PKEY_print_params prints a textual representation of the parameters in
409  * |pkey| to |out|. Returns one on success or zero otherwise. */
410 OPENSSL_EXPORT int EVP_PKEY_print_params(BIO *out, const EVP_PKEY *pkey,
411                                          int indent, ASN1_PCTX *pctx);
412 
413 
414 /* Password stretching.
415  *
416  * Password stretching functions take a low-entropy password and apply a slow
417  * function that results in a key suitable for use in symmetric
418  * cryptography. */
419 
420 /* PKCS5_PBKDF2_HMAC computes |iterations| iterations of PBKDF2 of |password|
421  * and |salt|, using |digest|, and outputs |key_len| bytes to |out_key|. It
422  * returns one on success and zero on error. */
423 OPENSSL_EXPORT int PKCS5_PBKDF2_HMAC(const char *password, size_t password_len,
424                                      const uint8_t *salt, size_t salt_len,
425                                      unsigned iterations, const EVP_MD *digest,
426                                      size_t key_len, uint8_t *out_key);
427 
428 /* PKCS5_PBKDF2_HMAC_SHA1 is the same as PKCS5_PBKDF2_HMAC, but with |digest|
429  * fixed to |EVP_sha1|. */
430 OPENSSL_EXPORT int PKCS5_PBKDF2_HMAC_SHA1(const char *password,
431                                           size_t password_len,
432                                           const uint8_t *salt, size_t salt_len,
433                                           unsigned iterations, size_t key_len,
434                                           uint8_t *out_key);
435 
436 /* EVP_PBE_scrypt expands |password| into a secret key of length |key_len| using
437  * scrypt, as described in RFC 7914, and writes the result to |out_key|. It
438  * returns one on success and zero on error.
439  *
440  * |N|, |r|, and |p| are as described in RFC 7914 section 6. They determine the
441  * cost of the operation. If the memory required exceeds |max_mem|, the
442  * operation will fail instead. If |max_mem| is zero, a defult limit of 32MiB
443  * will be used. */
444 OPENSSL_EXPORT int EVP_PBE_scrypt(const char *password, size_t password_len,
445                                   const uint8_t *salt, size_t salt_len,
446                                   uint64_t N, uint64_t r, uint64_t p,
447                                   size_t max_mem, uint8_t *out_key,
448                                   size_t key_len);
449 
450 
451 /* Public key contexts.
452  *
453  * |EVP_PKEY_CTX| objects hold the context of an operation (e.g. signing or
454  * encrypting) that uses a public key. */
455 
456 /* EVP_PKEY_CTX_new allocates a fresh |EVP_PKEY_CTX| for use with |pkey|. It
457  * returns the context or NULL on error. */
458 OPENSSL_EXPORT EVP_PKEY_CTX *EVP_PKEY_CTX_new(EVP_PKEY *pkey, ENGINE *e);
459 
460 /* EVP_PKEY_CTX_new_id allocates a fresh |EVP_PKEY_CTX| for a key of type |id|
461  * (e.g. |EVP_PKEY_HMAC|). This can be used for key generation where
462  * |EVP_PKEY_CTX_new| can't be used because there isn't an |EVP_PKEY| to pass
463  * it. It returns the context or NULL on error. */
464 OPENSSL_EXPORT EVP_PKEY_CTX *EVP_PKEY_CTX_new_id(int id, ENGINE *e);
465 
466 /* EVP_PKEY_CTX_free frees |ctx| and the data it owns. */
467 OPENSSL_EXPORT void EVP_PKEY_CTX_free(EVP_PKEY_CTX *ctx);
468 
469 /* EVP_PKEY_CTX_dup allocates a fresh |EVP_PKEY_CTX| and sets it equal to the
470  * state of |ctx|. It returns the fresh |EVP_PKEY_CTX| or NULL on error. */
471 OPENSSL_EXPORT EVP_PKEY_CTX *EVP_PKEY_CTX_dup(EVP_PKEY_CTX *ctx);
472 
473 /* EVP_PKEY_CTX_get0_pkey returns the |EVP_PKEY| associated with |ctx|. */
474 OPENSSL_EXPORT EVP_PKEY *EVP_PKEY_CTX_get0_pkey(EVP_PKEY_CTX *ctx);
475 
476 /* EVP_PKEY_sign_init initialises an |EVP_PKEY_CTX| for a signing operation. It
477  * should be called before |EVP_PKEY_sign|.
478  *
479  * It returns one on success or zero on error. */
480 OPENSSL_EXPORT int EVP_PKEY_sign_init(EVP_PKEY_CTX *ctx);
481 
482 /* EVP_PKEY_sign signs |digest_len| bytes from |digest| using |ctx|. If |sig| is
483  * NULL, the maximum size of the signature is written to
484  * |out_sig_len|. Otherwise, |*sig_len| must contain the number of bytes of
485  * space available at |sig|. If sufficient, the signature will be written to
486  * |sig| and |*sig_len| updated with the true length.
487  *
488  * This function expects a pre-hashed input and will fail for signature
489  * algorithms which do not support this. Use |EVP_DigestSignInit| to sign an
490  * unhashed input.
491  *
492  * WARNING: Setting |sig| to NULL only gives the maximum size of the
493  * signature. The actual signature may be smaller.
494  *
495  * It returns one on success or zero on error. (Note: this differs from
496  * OpenSSL, which can also return negative values to indicate an error. ) */
497 OPENSSL_EXPORT int EVP_PKEY_sign(EVP_PKEY_CTX *ctx, uint8_t *sig,
498                                  size_t *sig_len, const uint8_t *digest,
499                                  size_t digest_len);
500 
501 /* EVP_PKEY_verify_init initialises an |EVP_PKEY_CTX| for a signature
502  * verification operation. It should be called before |EVP_PKEY_verify|.
503  *
504  * It returns one on success or zero on error. */
505 OPENSSL_EXPORT int EVP_PKEY_verify_init(EVP_PKEY_CTX *ctx);
506 
507 /* EVP_PKEY_verify verifies that |sig_len| bytes from |sig| are a valid
508  * signature for |digest|.
509  *
510  * This function expects a pre-hashed input and will fail for signature
511  * algorithms which do not support this. Use |EVP_DigestVerifyInit| to verify a
512  * signature given the unhashed input.
513  *
514  * It returns one on success or zero on error. */
515 OPENSSL_EXPORT int EVP_PKEY_verify(EVP_PKEY_CTX *ctx, const uint8_t *sig,
516                                    size_t sig_len, const uint8_t *digest,
517                                    size_t digest_len);
518 
519 /* EVP_PKEY_encrypt_init initialises an |EVP_PKEY_CTX| for an encryption
520  * operation. It should be called before |EVP_PKEY_encrypt|.
521  *
522  * It returns one on success or zero on error. */
523 OPENSSL_EXPORT int EVP_PKEY_encrypt_init(EVP_PKEY_CTX *ctx);
524 
525 /* EVP_PKEY_encrypt encrypts |in_len| bytes from |in|. If |out| is NULL, the
526  * maximum size of the ciphertext is written to |out_len|. Otherwise, |*out_len|
527  * must contain the number of bytes of space available at |out|. If sufficient,
528  * the ciphertext will be written to |out| and |*out_len| updated with the true
529  * length.
530  *
531  * WARNING: Setting |out| to NULL only gives the maximum size of the
532  * ciphertext. The actual ciphertext may be smaller.
533  *
534  * It returns one on success or zero on error. */
535 OPENSSL_EXPORT int EVP_PKEY_encrypt(EVP_PKEY_CTX *ctx, uint8_t *out,
536                                     size_t *out_len, const uint8_t *in,
537                                     size_t in_len);
538 
539 /* EVP_PKEY_decrypt_init initialises an |EVP_PKEY_CTX| for a decryption
540  * operation. It should be called before |EVP_PKEY_decrypt|.
541  *
542  * It returns one on success or zero on error. */
543 OPENSSL_EXPORT int EVP_PKEY_decrypt_init(EVP_PKEY_CTX *ctx);
544 
545 /* EVP_PKEY_decrypt decrypts |in_len| bytes from |in|. If |out| is NULL, the
546  * maximum size of the plaintext is written to |out_len|. Otherwise, |*out_len|
547  * must contain the number of bytes of space available at |out|. If sufficient,
548  * the ciphertext will be written to |out| and |*out_len| updated with the true
549  * length.
550  *
551  * WARNING: Setting |out| to NULL only gives the maximum size of the
552  * plaintext. The actual plaintext may be smaller.
553  *
554  * It returns one on success or zero on error. */
555 OPENSSL_EXPORT int EVP_PKEY_decrypt(EVP_PKEY_CTX *ctx, uint8_t *out,
556                                     size_t *out_len, const uint8_t *in,
557                                     size_t in_len);
558 
559 /* EVP_PKEY_verify_recover_init initialises an |EVP_PKEY_CTX| for a public-key
560  * decryption operation. It should be called before |EVP_PKEY_verify_recover|.
561  *
562  * Public-key decryption is a very obscure operation that is only implemented
563  * by RSA keys. It is effectively a signature verification operation that
564  * returns the signed message directly. It is almost certainly not what you
565  * want.
566  *
567  * It returns one on success or zero on error. */
568 OPENSSL_EXPORT int EVP_PKEY_verify_recover_init(EVP_PKEY_CTX *ctx);
569 
570 /* EVP_PKEY_verify_recover decrypts |sig_len| bytes from |sig|. If |out| is
571  * NULL, the maximum size of the plaintext is written to |out_len|. Otherwise,
572  * |*out_len| must contain the number of bytes of space available at |out|. If
573  * sufficient, the ciphertext will be written to |out| and |*out_len| updated
574  * with the true length.
575  *
576  * WARNING: Setting |out| to NULL only gives the maximum size of the
577  * plaintext. The actual plaintext may be smaller.
578  *
579  * See the warning about this operation in |EVP_PKEY_verify_recover_init|. It
580  * is probably not what you want.
581  *
582  * It returns one on success or zero on error. */
583 OPENSSL_EXPORT int EVP_PKEY_verify_recover(EVP_PKEY_CTX *ctx, uint8_t *out,
584                                            size_t *out_len, const uint8_t *sig,
585                                            size_t siglen);
586 
587 /* EVP_PKEY_derive_init initialises an |EVP_PKEY_CTX| for a key derivation
588  * operation. It should be called before |EVP_PKEY_derive_set_peer| and
589  * |EVP_PKEY_derive|.
590  *
591  * It returns one on success or zero on error. */
592 OPENSSL_EXPORT int EVP_PKEY_derive_init(EVP_PKEY_CTX *ctx);
593 
594 /* EVP_PKEY_derive_set_peer sets the peer's key to be used for key derivation
595  * by |ctx| to |peer|. It should be called after |EVP_PKEY_derive_init|. (For
596  * example, this is used to set the peer's key in (EC)DH.) It returns one on
597  * success and zero on error. */
598 OPENSSL_EXPORT int EVP_PKEY_derive_set_peer(EVP_PKEY_CTX *ctx, EVP_PKEY *peer);
599 
600 /* EVP_PKEY_derive derives a shared key between the two keys configured in
601  * |ctx|. If |key| is non-NULL then, on entry, |out_key_len| must contain the
602  * amount of space at |key|. If sufficient then the shared key will be written
603  * to |key| and |*out_key_len| will be set to the length. If |key| is NULL then
604  * |out_key_len| will be set to the maximum length.
605  *
606  * WARNING: Setting |out| to NULL only gives the maximum size of the key. The
607  * actual key may be smaller.
608  *
609  * It returns one on success and zero on error. */
610 OPENSSL_EXPORT int EVP_PKEY_derive(EVP_PKEY_CTX *ctx, uint8_t *key,
611                                    size_t *out_key_len);
612 
613 /* EVP_PKEY_keygen_init initialises an |EVP_PKEY_CTX| for a key generation
614  * operation. It should be called before |EVP_PKEY_keygen|.
615  *
616  * It returns one on success or zero on error. */
617 OPENSSL_EXPORT int EVP_PKEY_keygen_init(EVP_PKEY_CTX *ctx);
618 
619 /* EVP_PKEY_keygen performs a key generation operation using the values from
620  * |ctx| and sets |*ppkey| to a fresh |EVP_PKEY| containing the resulting key.
621  * It returns one on success or zero on error. */
622 OPENSSL_EXPORT int EVP_PKEY_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey);
623 
624 
625 /* Generic control functions. */
626 
627 /* EVP_PKEY_CTX_set_signature_md sets |md| as the digest to be used in a
628  * signature operation. It returns one on success or zero on error. */
629 OPENSSL_EXPORT int EVP_PKEY_CTX_set_signature_md(EVP_PKEY_CTX *ctx,
630                                                  const EVP_MD *md);
631 
632 /* EVP_PKEY_CTX_get_signature_md sets |*out_md| to the digest to be used in a
633  * signature operation. It returns one on success or zero on error. */
634 OPENSSL_EXPORT int EVP_PKEY_CTX_get_signature_md(EVP_PKEY_CTX *ctx,
635                                                  const EVP_MD **out_md);
636 
637 
638 /* RSA specific control functions. */
639 
640 /* EVP_PKEY_CTX_set_rsa_padding sets the padding type to use. It should be one
641  * of the |RSA_*_PADDING| values. Returns one on success or zero on error. */
642 OPENSSL_EXPORT int EVP_PKEY_CTX_set_rsa_padding(EVP_PKEY_CTX *ctx, int padding);
643 
644 /* EVP_PKEY_CTX_get_rsa_padding sets |*out_padding| to the current padding
645  * value, which is one of the |RSA_*_PADDING| values. Returns one on success or
646  * zero on error. */
647 OPENSSL_EXPORT int EVP_PKEY_CTX_get_rsa_padding(EVP_PKEY_CTX *ctx,
648                                                 int *out_padding);
649 
650 /* EVP_PKEY_CTX_set_rsa_pss_saltlen sets the length of the salt in a PSS-padded
651  * signature. A value of -1 cause the salt to be the same length as the digest
652  * in the signature. A value of -2 causes the salt to be the maximum length
653  * that will fit when signing and recovered from the signature when verifying.
654  * Otherwise the value gives the size of the salt in bytes.
655  *
656  * If unsure, use -1.
657  *
658  * Returns one on success or zero on error. */
659 OPENSSL_EXPORT int EVP_PKEY_CTX_set_rsa_pss_saltlen(EVP_PKEY_CTX *ctx,
660                                                     int salt_len);
661 
662 /* EVP_PKEY_CTX_get_rsa_pss_saltlen sets |*out_salt_len| to the salt length of
663  * a PSS-padded signature. See the documentation for
664  * |EVP_PKEY_CTX_set_rsa_pss_saltlen| for details of the special values that it
665  * can take.
666  *
667  * Returns one on success or zero on error. */
668 OPENSSL_EXPORT int EVP_PKEY_CTX_get_rsa_pss_saltlen(EVP_PKEY_CTX *ctx,
669                                                     int *out_salt_len);
670 
671 /* EVP_PKEY_CTX_set_rsa_keygen_bits sets the size of the desired RSA modulus,
672  * in bits, for key generation. Returns one on success or zero on
673  * error. */
674 OPENSSL_EXPORT int EVP_PKEY_CTX_set_rsa_keygen_bits(EVP_PKEY_CTX *ctx,
675                                                     int bits);
676 
677 /* EVP_PKEY_CTX_set_rsa_keygen_pubexp sets |e| as the public exponent for key
678  * generation. Returns one on success or zero on error. */
679 OPENSSL_EXPORT int EVP_PKEY_CTX_set_rsa_keygen_pubexp(EVP_PKEY_CTX *ctx,
680                                                       BIGNUM *e);
681 
682 /* EVP_PKEY_CTX_set_rsa_oaep_md sets |md| as the digest used in OAEP padding.
683  * Returns one on success or zero on error. */
684 OPENSSL_EXPORT int EVP_PKEY_CTX_set_rsa_oaep_md(EVP_PKEY_CTX *ctx,
685                                                 const EVP_MD *md);
686 
687 /* EVP_PKEY_CTX_get_rsa_oaep_md sets |*out_md| to the digest function used in
688  * OAEP padding. Returns one on success or zero on error. */
689 OPENSSL_EXPORT int EVP_PKEY_CTX_get_rsa_oaep_md(EVP_PKEY_CTX *ctx,
690                                                 const EVP_MD **out_md);
691 
692 /* EVP_PKEY_CTX_set_rsa_mgf1_md sets |md| as the digest used in MGF1. Returns
693  * one on success or zero on error. */
694 OPENSSL_EXPORT int EVP_PKEY_CTX_set_rsa_mgf1_md(EVP_PKEY_CTX *ctx,
695                                                 const EVP_MD *md);
696 
697 /* EVP_PKEY_CTX_get_rsa_mgf1_md sets |*out_md| to the digest function used in
698  * MGF1. Returns one on success or zero on error. */
699 OPENSSL_EXPORT int EVP_PKEY_CTX_get_rsa_mgf1_md(EVP_PKEY_CTX *ctx,
700                                                 const EVP_MD **out_md);
701 
702 /* EVP_PKEY_CTX_set0_rsa_oaep_label sets |label_len| bytes from |label| as the
703  * label used in OAEP. DANGER: On success, this call takes ownership of |label|
704  * and will call |OPENSSL_free| on it when |ctx| is destroyed.
705  *
706  * Returns one on success or zero on error. */
707 OPENSSL_EXPORT int EVP_PKEY_CTX_set0_rsa_oaep_label(EVP_PKEY_CTX *ctx,
708                                                     uint8_t *label,
709                                                     size_t label_len);
710 
711 /* EVP_PKEY_CTX_get0_rsa_oaep_label sets |*out_label| to point to the internal
712  * buffer containing the OAEP label (which may be NULL) and returns the length
713  * of the label or a negative value on error.
714  *
715  * WARNING: the return value differs from the usual return value convention. */
716 OPENSSL_EXPORT int EVP_PKEY_CTX_get0_rsa_oaep_label(EVP_PKEY_CTX *ctx,
717                                                     const uint8_t **out_label);
718 
719 
720 /* Deprecated functions. */
721 
722 /* EVP_PKEY_DH is defined for compatibility, but it is impossible to create an
723  * |EVP_PKEY| of that type. */
724 #define EVP_PKEY_DH NID_dhKeyAgreement
725 
726 /* EVP_PKEY_RSA2 was historically an alternate form for RSA public keys (OID
727  * 2.5.8.1.1), but is no longer accepted. */
728 #define EVP_PKEY_RSA2 NID_rsa
729 
730 /* OpenSSL_add_all_algorithms does nothing. */
731 OPENSSL_EXPORT void OpenSSL_add_all_algorithms(void);
732 
733 /* OPENSSL_add_all_algorithms_conf does nothing. */
734 OPENSSL_EXPORT void OPENSSL_add_all_algorithms_conf(void);
735 
736 /* OpenSSL_add_all_ciphers does nothing. */
737 OPENSSL_EXPORT void OpenSSL_add_all_ciphers(void);
738 
739 /* OpenSSL_add_all_digests does nothing. */
740 OPENSSL_EXPORT void OpenSSL_add_all_digests(void);
741 
742 /* EVP_cleanup does nothing. */
743 OPENSSL_EXPORT void EVP_cleanup(void);
744 
745 OPENSSL_EXPORT void EVP_CIPHER_do_all_sorted(
746     void (*callback)(const EVP_CIPHER *cipher, const char *name,
747                      const char *unused, void *arg),
748     void *arg);
749 
750 OPENSSL_EXPORT void EVP_MD_do_all_sorted(void (*callback)(const EVP_MD *cipher,
751                                                           const char *name,
752                                                           const char *unused,
753                                                           void *arg),
754                                          void *arg);
755 
756 /* i2d_PrivateKey marshals a private key from |key| to an ASN.1, DER
757  * structure. If |outp| is not NULL then the result is written to |*outp| and
758  * |*outp| is advanced just past the output. It returns the number of bytes in
759  * the result, whether written or not, or a negative value on error.
760  *
761  * RSA keys are serialized as a DER-encoded RSAPublicKey (RFC 3447) structure.
762  * EC keys are serialized as a DER-encoded ECPrivateKey (RFC 5915) structure.
763  *
764  * Use |RSA_marshal_private_key| or |EC_marshal_private_key| instead. */
765 OPENSSL_EXPORT int i2d_PrivateKey(const EVP_PKEY *key, uint8_t **outp);
766 
767 /* i2d_PublicKey marshals a public key from |key| to a type-specific format.
768  * If |outp| is not NULL then the result is written to |*outp| and
769  * |*outp| is advanced just past the output. It returns the number of bytes in
770  * the result, whether written or not, or a negative value on error.
771  *
772  * RSA keys are serialized as a DER-encoded RSAPublicKey (RFC 3447) structure.
773  * EC keys are serialized as an EC point per SEC 1.
774  *
775  * Use |RSA_marshal_public_key| or |EC_POINT_point2cbb| instead. */
776 OPENSSL_EXPORT int i2d_PublicKey(EVP_PKEY *key, uint8_t **outp);
777 
778 /* d2i_PrivateKey parses an ASN.1, DER-encoded, private key from |len| bytes at
779  * |*inp|. If |out| is not NULL then, on exit, a pointer to the result is in
780  * |*out|. Note that, even if |*out| is already non-NULL on entry, it will not
781  * be written to. Rather, a fresh |EVP_PKEY| is allocated and the previous one
782  * is freed. On successful exit, |*inp| is advanced past the DER structure. It
783  * returns the result or NULL on error.
784  *
785  * This function tries to detect one of several formats. Instead, use
786  * |EVP_parse_private_key| for a PrivateKeyInfo, |RSA_parse_private_key| for an
787  * RSAPrivateKey, and |EC_parse_private_key| for an ECPrivateKey. */
788 OPENSSL_EXPORT EVP_PKEY *d2i_PrivateKey(int type, EVP_PKEY **out,
789                                         const uint8_t **inp, long len);
790 
791 /* d2i_AutoPrivateKey acts the same as |d2i_PrivateKey|, but detects the type
792  * of the private key.
793  *
794  * This function tries to detect one of several formats. Instead, use
795  * |EVP_parse_private_key| for a PrivateKeyInfo, |RSA_parse_private_key| for an
796  * RSAPrivateKey, and |EC_parse_private_key| for an ECPrivateKey. */
797 OPENSSL_EXPORT EVP_PKEY *d2i_AutoPrivateKey(EVP_PKEY **out, const uint8_t **inp,
798                                             long len);
799 
800 /* EVP_PKEY_get0_DH returns NULL. */
801 OPENSSL_EXPORT DH *EVP_PKEY_get0_DH(EVP_PKEY *pkey);
802 
803 
804 /* Private structures. */
805 
806 struct evp_pkey_st {
807   CRYPTO_refcount_t references;
808 
809   /* type contains one of the EVP_PKEY_* values or NID_undef and determines
810    * which element (if any) of the |pkey| union is valid. */
811   int type;
812 
813   union {
814     void *ptr;
815     RSA *rsa;
816     DSA *dsa;
817     DH *dh;
818     EC_KEY *ec;
819   } pkey;
820 
821   /* ameth contains a pointer to a method table that contains many ASN.1
822    * methods for the key type. */
823   const EVP_PKEY_ASN1_METHOD *ameth;
824 } /* EVP_PKEY */;
825 
826 
827 #if defined(__cplusplus)
828 }  /* extern C */
829 
830 extern "C++" {
831 namespace bssl {
832 
833 BORINGSSL_MAKE_DELETER(EVP_PKEY, EVP_PKEY_free)
834 BORINGSSL_MAKE_DELETER(EVP_PKEY_CTX, EVP_PKEY_CTX_free)
835 
836 }  // namespace bssl
837 
838 }  /* extern C++ */
839 
840 #endif
841 
842 #define EVP_R_BUFFER_TOO_SMALL 100
843 #define EVP_R_COMMAND_NOT_SUPPORTED 101
844 #define EVP_R_DECODE_ERROR 102
845 #define EVP_R_DIFFERENT_KEY_TYPES 103
846 #define EVP_R_DIFFERENT_PARAMETERS 104
847 #define EVP_R_ENCODE_ERROR 105
848 #define EVP_R_EXPECTING_AN_EC_KEY_KEY 106
849 #define EVP_R_EXPECTING_AN_RSA_KEY 107
850 #define EVP_R_EXPECTING_A_DSA_KEY 108
851 #define EVP_R_ILLEGAL_OR_UNSUPPORTED_PADDING_MODE 109
852 #define EVP_R_INVALID_DIGEST_LENGTH 110
853 #define EVP_R_INVALID_DIGEST_TYPE 111
854 #define EVP_R_INVALID_KEYBITS 112
855 #define EVP_R_INVALID_MGF1_MD 113
856 #define EVP_R_INVALID_OPERATION 114
857 #define EVP_R_INVALID_PADDING_MODE 115
858 #define EVP_R_INVALID_PSS_SALTLEN 116
859 #define EVP_R_KEYS_NOT_SET 117
860 #define EVP_R_MISSING_PARAMETERS 118
861 #define EVP_R_NO_DEFAULT_DIGEST 119
862 #define EVP_R_NO_KEY_SET 120
863 #define EVP_R_NO_MDC2_SUPPORT 121
864 #define EVP_R_NO_NID_FOR_CURVE 122
865 #define EVP_R_NO_OPERATION_SET 123
866 #define EVP_R_NO_PARAMETERS_SET 124
867 #define EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE 125
868 #define EVP_R_OPERATON_NOT_INITIALIZED 126
869 #define EVP_R_UNKNOWN_PUBLIC_KEY_TYPE 127
870 #define EVP_R_UNSUPPORTED_ALGORITHM 128
871 #define EVP_R_UNSUPPORTED_PUBLIC_KEY_TYPE 129
872 #define EVP_R_NOT_A_PRIVATE_KEY 130
873 #define EVP_R_INVALID_SIGNATURE 131
874 #define EVP_R_MEMORY_LIMIT_EXCEEDED 132
875 #define EVP_R_INVALID_PARAMETERS 133
876 
877 #endif  /* OPENSSL_HEADER_EVP_H */
878