diff --git a/src/3rdparty/monocypher/monocypher.h b/src/3rdparty/monocypher/monocypher.h
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+// Monocypher version 4.0.2
+//
+// This file is dual-licensed. Choose whichever licence you want from
+// the two licences listed below.
+//
+// The first licence is a regular 2-clause BSD licence. The second licence
+// is the CC-0 from Creative Commons. It is intended to release Monocypher
+// to the public domain. The BSD licence serves as a fallback option.
+//
+// SPDX-License-Identifier: BSD-2-Clause OR CC0-1.0
+//
+// ------------------------------------------------------------------------
+//
+// Copyright (c) 2017-2019, Loup Vaillant
+// All rights reserved.
+//
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// 1. Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the
+// distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// ------------------------------------------------------------------------
+//
+// Written in 2017-2019 by Loup Vaillant
+//
+// To the extent possible under law, the author(s) have dedicated all copyright
+// and related neighboring rights to this software to the public domain
+// worldwide. This software is distributed without any warranty.
+//
+// You should have received a copy of the CC0 Public Domain Dedication along
+// with this software. If not, see
+//
+
+#ifndef MONOCYPHER_H
+#define MONOCYPHER_H
+
+#include
+#include
+
+#ifdef MONOCYPHER_CPP_NAMESPACE
+namespace MONOCYPHER_CPP_NAMESPACE {
+#elif defined(__cplusplus)
+extern "C" {
+#endif
+
+// Constant time comparisons
+// -------------------------
+
+// Return 0 if a and b are equal, -1 otherwise
+int crypto_verify16(const uint8_t a[16], const uint8_t b[16]);
+int crypto_verify32(const uint8_t a[32], const uint8_t b[32]);
+int crypto_verify64(const uint8_t a[64], const uint8_t b[64]);
+
+
+// Erase sensitive data
+// --------------------
+void crypto_wipe(void *secret, size_t size);
+
+
+// Authenticated encryption
+// ------------------------
+void crypto_aead_lock(uint8_t *cipher_text,
+ uint8_t mac [16],
+ const uint8_t key [32],
+ const uint8_t nonce[24],
+ const uint8_t *ad, size_t ad_size,
+ const uint8_t *plain_text, size_t text_size);
+int crypto_aead_unlock(uint8_t *plain_text,
+ const uint8_t mac [16],
+ const uint8_t key [32],
+ const uint8_t nonce[24],
+ const uint8_t *ad, size_t ad_size,
+ const uint8_t *cipher_text, size_t text_size);
+
+// Authenticated stream
+// --------------------
+typedef struct {
+ uint64_t counter;
+ uint8_t key[32];
+ uint8_t nonce[8];
+} crypto_aead_ctx;
+
+void crypto_aead_init_x(crypto_aead_ctx *ctx,
+ const uint8_t key[32], const uint8_t nonce[24]);
+void crypto_aead_init_djb(crypto_aead_ctx *ctx,
+ const uint8_t key[32], const uint8_t nonce[8]);
+void crypto_aead_init_ietf(crypto_aead_ctx *ctx,
+ const uint8_t key[32], const uint8_t nonce[12]);
+
+void crypto_aead_write(crypto_aead_ctx *ctx,
+ uint8_t *cipher_text,
+ uint8_t mac[16],
+ const uint8_t *ad , size_t ad_size,
+ const uint8_t *plain_text, size_t text_size);
+int crypto_aead_read(crypto_aead_ctx *ctx,
+ uint8_t *plain_text,
+ const uint8_t mac[16],
+ const uint8_t *ad , size_t ad_size,
+ const uint8_t *cipher_text, size_t text_size);
+
+
+// General purpose hash (BLAKE2b)
+// ------------------------------
+
+// Direct interface
+void crypto_blake2b(uint8_t *hash, size_t hash_size,
+ const uint8_t *message, size_t message_size);
+
+void crypto_blake2b_keyed(uint8_t *hash, size_t hash_size,
+ const uint8_t *key, size_t key_size,
+ const uint8_t *message, size_t message_size);
+
+// Incremental interface
+typedef struct {
+ // Do not rely on the size or contents of this type,
+ // for they may change without notice.
+ uint64_t hash[8];
+ uint64_t input_offset[2];
+ uint64_t input[16];
+ size_t input_idx;
+ size_t hash_size;
+} crypto_blake2b_ctx;
+
+void crypto_blake2b_init(crypto_blake2b_ctx *ctx, size_t hash_size);
+void crypto_blake2b_keyed_init(crypto_blake2b_ctx *ctx, size_t hash_size,
+ const uint8_t *key, size_t key_size);
+void crypto_blake2b_update(crypto_blake2b_ctx *ctx,
+ const uint8_t *message, size_t message_size);
+void crypto_blake2b_final(crypto_blake2b_ctx *ctx, uint8_t *hash);
+
+
+// Password key derivation (Argon2)
+// --------------------------------
+#define CRYPTO_ARGON2_D 0
+#define CRYPTO_ARGON2_I 1
+#define CRYPTO_ARGON2_ID 2
+
+typedef struct {
+ uint32_t algorithm; // Argon2d, Argon2i, Argon2id
+ uint32_t nb_blocks; // memory hardness, >= 8 * nb_lanes
+ uint32_t nb_passes; // CPU hardness, >= 1 (>= 3 recommended for Argon2i)
+ uint32_t nb_lanes; // parallelism level (single threaded anyway)
+} crypto_argon2_config;
+
+typedef struct {
+ const uint8_t *pass;
+ const uint8_t *salt;
+ uint32_t pass_size;
+ uint32_t salt_size; // 16 bytes recommended
+} crypto_argon2_inputs;
+
+typedef struct {
+ const uint8_t *key; // may be NULL if no key
+ const uint8_t *ad; // may be NULL if no additional data
+ uint32_t key_size; // 0 if no key (32 bytes recommended otherwise)
+ uint32_t ad_size; // 0 if no additional data
+} crypto_argon2_extras;
+
+extern const crypto_argon2_extras crypto_argon2_no_extras;
+
+void crypto_argon2(uint8_t *hash, uint32_t hash_size, void *work_area,
+ crypto_argon2_config config,
+ crypto_argon2_inputs inputs,
+ crypto_argon2_extras extras);
+
+
+// Key exchange (X-25519)
+// ----------------------
+
+// Shared secrets are not quite random.
+// Hash them to derive an actual shared key.
+void crypto_x25519_public_key(uint8_t public_key[32],
+ const uint8_t secret_key[32]);
+void crypto_x25519(uint8_t raw_shared_secret[32],
+ const uint8_t your_secret_key [32],
+ const uint8_t their_public_key [32]);
+
+// Conversion to EdDSA
+void crypto_x25519_to_eddsa(uint8_t eddsa[32], const uint8_t x25519[32]);
+
+// scalar "division"
+// Used for OPRF. Be aware that exponential blinding is less secure
+// than Diffie-Hellman key exchange.
+void crypto_x25519_inverse(uint8_t blind_salt [32],
+ const uint8_t private_key[32],
+ const uint8_t curve_point[32]);
+
+// "Dirty" versions of x25519_public_key().
+// Use with crypto_elligator_rev().
+// Leaks 3 bits of the private key.
+void crypto_x25519_dirty_small(uint8_t pk[32], const uint8_t sk[32]);
+void crypto_x25519_dirty_fast (uint8_t pk[32], const uint8_t sk[32]);
+
+
+// Signatures
+// ----------
+
+// EdDSA with curve25519 + BLAKE2b
+void crypto_eddsa_key_pair(uint8_t secret_key[64],
+ uint8_t public_key[32],
+ uint8_t seed[32]);
+void crypto_eddsa_sign(uint8_t signature [64],
+ const uint8_t secret_key[64],
+ const uint8_t *message, size_t message_size);
+int crypto_eddsa_check(const uint8_t signature [64],
+ const uint8_t public_key[32],
+ const uint8_t *message, size_t message_size);
+
+// Conversion to X25519
+void crypto_eddsa_to_x25519(uint8_t x25519[32], const uint8_t eddsa[32]);
+
+// EdDSA building blocks
+void crypto_eddsa_trim_scalar(uint8_t out[32], const uint8_t in[32]);
+void crypto_eddsa_reduce(uint8_t reduced[32], const uint8_t expanded[64]);
+void crypto_eddsa_mul_add(uint8_t r[32],
+ const uint8_t a[32],
+ const uint8_t b[32],
+ const uint8_t c[32]);
+void crypto_eddsa_scalarbase(uint8_t point[32], const uint8_t scalar[32]);
+int crypto_eddsa_check_equation(const uint8_t signature[64],
+ const uint8_t public_key[32],
+ const uint8_t h_ram[32]);
+
+
+// Chacha20
+// --------
+
+// Specialised hash.
+// Used to hash X25519 shared secrets.
+void crypto_chacha20_h(uint8_t out[32],
+ const uint8_t key[32],
+ const uint8_t in [16]);
+
+// Unauthenticated stream cipher.
+// Don't forget to add authentication.
+uint64_t crypto_chacha20_djb(uint8_t *cipher_text,
+ const uint8_t *plain_text,
+ size_t text_size,
+ const uint8_t key[32],
+ const uint8_t nonce[8],
+ uint64_t ctr);
+uint32_t crypto_chacha20_ietf(uint8_t *cipher_text,
+ const uint8_t *plain_text,
+ size_t text_size,
+ const uint8_t key[32],
+ const uint8_t nonce[12],
+ uint32_t ctr);
+uint64_t crypto_chacha20_x(uint8_t *cipher_text,
+ const uint8_t *plain_text,
+ size_t text_size,
+ const uint8_t key[32],
+ const uint8_t nonce[24],
+ uint64_t ctr);
+
+
+// Poly 1305
+// ---------
+
+// This is a *one time* authenticator.
+// Disclosing the mac reveals the key.
+// See crypto_lock() on how to use it properly.
+
+// Direct interface
+void crypto_poly1305(uint8_t mac[16],
+ const uint8_t *message, size_t message_size,
+ const uint8_t key[32]);
+
+// Incremental interface
+typedef struct {
+ // Do not rely on the size or contents of this type,
+ // for they may change without notice.
+ uint8_t c[16]; // chunk of the message
+ size_t c_idx; // How many bytes are there in the chunk.
+ uint32_t r [4]; // constant multiplier (from the secret key)
+ uint32_t pad[4]; // random number added at the end (from the secret key)
+ uint32_t h [5]; // accumulated hash
+} crypto_poly1305_ctx;
+
+void crypto_poly1305_init (crypto_poly1305_ctx *ctx, const uint8_t key[32]);
+void crypto_poly1305_update(crypto_poly1305_ctx *ctx,
+ const uint8_t *message, size_t message_size);
+void crypto_poly1305_final (crypto_poly1305_ctx *ctx, uint8_t mac[16]);
+
+
+// Elligator 2
+// -----------
+
+// Elligator mappings proper
+void crypto_elligator_map(uint8_t curve [32], const uint8_t hidden[32]);
+int crypto_elligator_rev(uint8_t hidden[32], const uint8_t curve [32],
+ uint8_t tweak);
+
+// Easy to use key pair generation
+void crypto_elligator_key_pair(uint8_t hidden[32], uint8_t secret_key[32],
+ uint8_t seed[32]);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // MONOCYPHER_H