1 /* Copyright (c) 2020, Google Inc.
2  *
3  * Permission to use, copy, modify, and/or distribute this software for any
4  * purpose with or without fee is hereby granted, provided that the above
5  * copyright notice and this permission notice appear in all copies.
6  *
7  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10  * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14 
15 #ifndef OPENSSL_HEADER_EC_EXTRA_INTERNAL_H
16 #define OPENSSL_HEADER_EC_EXTRA_INTERNAL_H
17 
18 #include <openssl/ec.h>
19 
20 #include "../fipsmodule/ec/internal.h"
21 
22 #if defined(__cplusplus)
23 extern "C" {
24 #endif
25 
26 
27 // Hash-to-curve.
28 //
29 // The following functions implement primitives from
30 // draft-irtf-cfrg-hash-to-curve. The |dst| parameter in each function is the
31 // domain separation tag and must be unique for each protocol and between the
32 // |hash_to_curve| and |hash_to_scalar| variants. See section 3.1 of the spec
33 // for additional guidance on this parameter.
34 
35 // ec_hash_to_curve_p384_xmd_sha512_sswu_draft07 hashes |msg| to a point on
36 // |group| and writes the result to |out|, implementing the
37 // P384_XMD:SHA-512_SSWU_RO_ suite from draft-irtf-cfrg-hash-to-curve-07. It
38 // returns one on success and zero on error.
39 OPENSSL_EXPORT int ec_hash_to_curve_p384_xmd_sha512_sswu_draft07(
40     const EC_GROUP *group, EC_RAW_POINT *out, const uint8_t *dst,
41     size_t dst_len, const uint8_t *msg, size_t msg_len);
42 
43 // ec_hash_to_scalar_p384_xmd_sha512_draft07 hashes |msg| to a scalar on |group|
44 // and writes the result to |out|, using the hash_to_field operation from the
45 // P384_XMD:SHA-512_SSWU_RO_ suite from draft-irtf-cfrg-hash-to-curve-07, but
46 // generating a value modulo the group order rather than a field element.
47 OPENSSL_EXPORT int ec_hash_to_scalar_p384_xmd_sha512_draft07(
48     const EC_GROUP *group, EC_SCALAR *out, const uint8_t *dst, size_t dst_len,
49     const uint8_t *msg, size_t msg_len);
50 
51 
52 #if defined(__cplusplus)
53 }  // extern C
54 #endif
55 
56 #endif  // OPENSSL_HEADER_EC_EXTRA_INTERNAL_H
57