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3 Copyright (C) 2012, 2013, 2019 GNUnet e.V.
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
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11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Affero General Public License for more details.
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18 SPDX-License-Identifier: AGPL3.0-or-later
21 * @file util/crypto_pow.c
22 * @brief proof-of-work hashing
23 * @author Christian Grothoff
27 #include "gnunet_crypto_lib.h"
31 * Calculate the 'proof-of-work' hash (an expensive hash).
32 * We're using a non-standard formula to avoid issues with
33 * ASICs appearing (see #3795).
35 * @param salt salt for the hash. Must be crypto_pwhash_argon2id_SALTBYTES long.
36 * @param buf data to hash
37 * @param buf_len number of bytes in @a buf
38 * @param result where to write the resulting hash
41 GNUNET_CRYPTO_pow_hash (const char *salt,
44 struct GNUNET_HashCode *result)
46 GNUNET_assert (strlen (salt) == crypto_pwhash_argon2id_SALTBYTES);
47 /* Threads hardcoded at 1 in libsodium */
49 crypto_pwhash_argon2id ((unsigned char *) result,
50 sizeof (struct GNUNET_HashCode),
53 (unsigned char*) salt,
55 1024 * 1024, /* memory (1 MiB) */
56 crypto_pwhash_argon2id_ALG_ARGON2ID13));
60 /* end of crypto_pow.c */