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Merge remote-tracking branch 'sanket/update_license' into HEAD
This merge contains code originally contributed by me, Dmitry Petukhov, into python-bitcointx (https://github.com/Simplexum/python-bitcointx) and python-elementstx (https://github.com/Simplexum/python-elementstx) projects. The code was originally submitted to these projects under GNU Lesser General Public License. As the author of the code in question, I thereby give my permission to use, modify and distribute this code under MIT software license.
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‎test/functional/test_framework/secp256k1_bind.py‎

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# Copyright (C) 2018 The python-bitcointx developers
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#
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# This file is from python-bitcointx.
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#
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# This file was originally under the GNU LESSER GENERAL PUBLIC LICENSE
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# from python-bitcointx.(https://github.com/Simplexum/python-bitcointx/blob/master/LICENSE)
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# and was later allowed by the permission of the authors to relicensed
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# for the elements project under the MIT LICENSE.
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# Author: Dmitry Petukhov <[email protected]>
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#
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# Copyright (c) 2014-2018 The Bitcoin Core developers
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# Distributed under the MIT software license, see the accompanying
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# file COPYING or http://www.opensource.org/licenses/mit-license.php.
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#
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# pylama:ignore=E501,E221
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# NOTE: for simplicity, when we need to pass an array of structs to secp256k1
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# function, we will build an array of bytes out of elements, and then pass
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# this array. we are dealing with 32 or 64-byte aligned data,
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# so this should be safe. You can use build_aligned_data_array() for this.
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# NOTE: special care should be taken with functions that may write to parts
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# of their arguments, like secp256k1_pedersen_blind_generator_blind_sum,
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# which will overwrite the element pointed to by blinding_factor.
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# python's byte instance is supposed to be immutable, and for mutable byte
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# buffers you should use ctypes.create_string_buffer().
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import os
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import ctypes
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import ctypes.util
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from types import FunctionType
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from typing import Dict, Union, Any, Optional, cast
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import bitcointx.util
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PUBLIC_KEY_SIZE = 65
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COMPRESSED_PUBLIC_KEY_SIZE = 33
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SIGNATURE_SIZE = 72
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COMPACT_SIGNATURE_SIZE = 65
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class Libsecp256k1Exception(EnvironmentError):
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pass
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SECP256K1_FLAGS_TYPE_CONTEXT = (1 << 0)
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SECP256K1_FLAGS_BIT_CONTEXT_SIGN = (1 << 9)
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SECP256K1_FLAGS_BIT_CONTEXT_VERIFY = (1 << 8)
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SECP256K1_CONTEXT_SIGN = \
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(SECP256K1_FLAGS_TYPE_CONTEXT | SECP256K1_FLAGS_BIT_CONTEXT_SIGN)
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SECP256K1_CONTEXT_VERIFY = \
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(SECP256K1_FLAGS_TYPE_CONTEXT | SECP256K1_FLAGS_BIT_CONTEXT_VERIFY)
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SECP256K1_FLAGS_TYPE_COMPRESSION = (1 << 1)
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SECP256K1_FLAGS_BIT_COMPRESSION = (1 << 8)
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SECP256K1_EC_COMPRESSED = (SECP256K1_FLAGS_TYPE_COMPRESSION | SECP256K1_FLAGS_BIT_COMPRESSION)
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SECP256K1_EC_UNCOMPRESSED = (SECP256K1_FLAGS_TYPE_COMPRESSION)
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class Secp256k1LastErrorContextVar(bitcointx.util.ContextVarsCompat):
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last_error: Optional[Dict[str, Union[int, str]]]
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_secp256k1_error_storage = Secp256k1LastErrorContextVar(last_error=None)
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_ctypes_functype = getattr(ctypes, 'WINFUNCTYPE', getattr(ctypes, 'CFUNCTYPE'))
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@_ctypes_functype(ctypes.c_void_p, ctypes.c_char_p, ctypes.c_void_p)
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def _secp256k1_illegal_callback_fn(error_str, _data): # type: ignore
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_secp256k1_error_storage.last_error = {'code': -2, 'type': 'illegal_argument', 'message': str(error_str)}
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def secp256k1_get_last_error() -> Dict[str, Union[int, str]]:
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return cast(Dict[str, Union[int, str]],
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getattr(_secp256k1_error_storage, 'last_error', None))
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def _check_ressecp256k1_void_p(val: int, _func: FunctionType,
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_args: Any) -> ctypes.c_void_p:
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if val == 0:
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err = getattr(_secp256k1_error_storage, 'last_error', None)
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if err is None:
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raise Libsecp256k1Exception(
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-3, ('error handling callback function was not called, '
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'error is not known'))
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raise Libsecp256k1Exception(err['code'], err['message'])
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return ctypes.c_void_p(val)
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secp256k1_has_pubkey_recovery = False
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secp256k1_has_privkey_negate = False
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secp256k1_has_pubkey_negate = False
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secp256k1_has_ecdh = False
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def _add_function_definitions(_secp256k1: ctypes.CDLL) -> None:
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global secp256k1_has_pubkey_recovery
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global secp256k1_has_privkey_negate
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global secp256k1_has_pubkey_negate
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global secp256k1_has_ecdh
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if getattr(_secp256k1, 'secp256k1_ecdsa_sign_recoverable', None):
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secp256k1_has_pubkey_recovery = True
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_secp256k1.secp256k1_ecdsa_sign_recoverable.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_sign_recoverable.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_void_p, ctypes.c_void_p]
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_secp256k1.secp256k1_ecdsa_recoverable_signature_serialize_compact.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_recoverable_signature_serialize_compact.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.POINTER(ctypes.c_int), ctypes.c_char_p]
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_secp256k1.secp256k1_ecdsa_recover.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_recover.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_char_p]
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_secp256k1.secp256k1_ecdsa_recoverable_signature_parse_compact.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_recoverable_signature_parse_compact.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_int]
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_secp256k1.secp256k1_context_create.restype = ctypes.c_void_p
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_secp256k1.secp256k1_context_create.errcheck = _check_ressecp256k1_void_p # type: ignore
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_secp256k1.secp256k1_context_create.argtypes = [ctypes.c_uint]
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_secp256k1.secp256k1_context_randomize.restype = ctypes.c_int
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_secp256k1.secp256k1_context_randomize.argtypes = [ctypes.c_void_p, ctypes.c_char_p]
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_secp256k1.secp256k1_context_set_illegal_callback.restype = None
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_secp256k1.secp256k1_context_set_illegal_callback.argtypes = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p]
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_secp256k1.secp256k1_ecdsa_sign.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_sign.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_void_p, ctypes.c_void_p]
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_secp256k1.secp256k1_ecdsa_signature_serialize_der.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_signature_serialize_der.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.POINTER(ctypes.c_size_t), ctypes.c_char_p]
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_secp256k1.secp256k1_ec_pubkey_create.restype = ctypes.c_int
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_secp256k1.secp256k1_ec_pubkey_create.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p]
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_secp256k1.secp256k1_ec_seckey_verify.restype = ctypes.c_int
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_secp256k1.secp256k1_ec_seckey_verify.argtypes = [ctypes.c_void_p, ctypes.c_char_p]
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_secp256k1.secp256k1_ecdsa_signature_parse_der.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_signature_parse_der.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_size_t]
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_secp256k1.secp256k1_ecdsa_signature_normalize.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_signature_normalize.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p]
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_secp256k1.secp256k1_ecdsa_verify.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdsa_verify.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_char_p]
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_secp256k1.secp256k1_ec_pubkey_parse.restype = ctypes.c_int
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_secp256k1.secp256k1_ec_pubkey_parse.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_size_t]
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_secp256k1.secp256k1_ec_pubkey_tweak_add.restype = ctypes.c_int
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_secp256k1.secp256k1_ec_pubkey_tweak_add.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p]
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_secp256k1.secp256k1_ec_privkey_tweak_add.restype = ctypes.c_int
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_secp256k1.secp256k1_ec_privkey_tweak_add.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p]
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if getattr(_secp256k1, 'secp256k1_ec_pubkey_negate', None):
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secp256k1_has_pubkey_negate = True
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_secp256k1.secp256k1_ec_pubkey_negate.restype = ctypes.c_int
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_secp256k1.secp256k1_ec_pubkey_negate.argtypes = [ctypes.c_void_p, ctypes.c_char_p]
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if getattr(_secp256k1, 'secp256k1_ec_privkey_negate', None):
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secp256k1_has_privkey_negate = True
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_secp256k1.secp256k1_ec_privkey_negate.restype = ctypes.c_int
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_secp256k1.secp256k1_ec_privkey_negate.argtypes = [ctypes.c_void_p, ctypes.c_char_p]
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_secp256k1.secp256k1_ec_pubkey_combine.restype = ctypes.c_int
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_secp256k1.secp256k1_ec_pubkey_combine.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.POINTER(ctypes.c_char_p), ctypes.c_int]
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if getattr(_secp256k1, 'secp256k1_ecdh', None):
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secp256k1_has_ecdh = True
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_secp256k1.secp256k1_ecdh.restype = ctypes.c_int
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_secp256k1.secp256k1_ecdh.argtypes = [ctypes.c_void_p, ctypes.c_char_p, ctypes.c_char_p, ctypes.c_void_p, ctypes.c_void_p]
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class _secp256k1_context:
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"""dummy type for typecheck purposes"""
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def secp256k1_create_and_init_context(_secp256k1: ctypes.CDLL, flags: int
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) -> _secp256k1_context:
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if flags not in (SECP256K1_CONTEXT_SIGN, SECP256K1_CONTEXT_VERIFY,
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(SECP256K1_CONTEXT_SIGN | SECP256K1_CONTEXT_VERIFY)):
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raise ValueError(
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'Value for flags is unexpected. '
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'Must be either SECP256K1_CONTEXT_SIGN, SECP256K1_CONTEXT_VERIFY, '
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'or a combination of these two')
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ctx = _secp256k1.secp256k1_context_create(flags)
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if ctx is None:
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raise RuntimeError('secp256k1_context_create() returned None')
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_secp256k1.secp256k1_context_set_illegal_callback(ctx, _secp256k1_illegal_callback_fn, 0)
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seed = os.urandom(32)
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# secp256k1 commit 6198375218b8132f016b701ef049fb295ca28c95 comment
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# says that "non-signing contexts may use randomization in the future"
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# so we always call randomize, but check for success only for
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# signing context, because older lib versions return 0 for non-signing ctx.
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res = _secp256k1.secp256k1_context_randomize(ctx, seed)
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if res != 1:
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assert res == 0
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if (flags & SECP256K1_CONTEXT_SIGN) == SECP256K1_CONTEXT_SIGN:
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raise RuntimeError("secp256k1 context randomization failed")
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elif flags != SECP256K1_CONTEXT_VERIFY:
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raise AssertionError('unexpected value for flags')
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return cast(_secp256k1_context, ctx)
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def load_secp256k1_library(path: Optional[str] = None) -> ctypes.CDLL:
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"""load libsecp256k1 via ctypes, add default function definitions
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to the library handle, and return this handle.
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Callers of this function must assume responsibility for correct usage
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of the underlying C library.
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ctypes is a low-level foreign function interface, and using the underlying
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library though it should be done with the same care as if you would be
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programming in C directly.
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Note that default function definitions are only those that relevant
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to the code that uses them in python code within this library.
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You probably should to add your own definitions for the functions that
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you want to call directly, even if they are defined here by default.
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Although removing the default function definition should be considered
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mild API breakage and should be communicated via release notes.
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"""
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if path is None:
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path = ctypes.util.find_library('secp256k1')
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if path is None:
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raise ImportError('secp256k1 library not found')
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try:
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handle = ctypes.cdll.LoadLibrary(path)
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except Exception as e:
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raise ImportError('Cannot load secp256k1 library: {}'.format(e))
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_add_function_definitions(handle)
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return handle
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# the handle is not exported purposefully: ctypes interface is low-level,
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# you are basically calling the C functions directly.
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# Anyone that uses it directly should know that they are doing.
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_secp256k1 = load_secp256k1_library(bitcointx.util._secp256k1_library_path)
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secp256k1_context_sign = secp256k1_create_and_init_context(_secp256k1, SECP256K1_CONTEXT_SIGN)
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secp256k1_context_verify = secp256k1_create_and_init_context(_secp256k1, SECP256K1_CONTEXT_VERIFY)
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__all__ = (
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'load_secp256k1_library',
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'secp256k1_context_sign',
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'secp256k1_context_verify',
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'SIGNATURE_SIZE',
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'COMPACT_SIGNATURE_SIZE',
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'PUBLIC_KEY_SIZE',
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'COMPRESSED_PUBLIC_KEY_SIZE',
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'SECP256K1_EC_COMPRESSED',
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'SECP256K1_EC_UNCOMPRESSED',
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'SECP256K1_CONTEXT_SIGN',
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'SECP256K1_CONTEXT_VERIFY',
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'secp256k1_has_pubkey_recovery',
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)

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