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Diffstat (limited to 'test/functional/test_framework/key.py')
| -rw-r--r-- | test/functional/test_framework/key.py | 232 |
1 files changed, 232 insertions, 0 deletions
diff --git a/test/functional/test_framework/key.py b/test/functional/test_framework/key.py new file mode 100644 index 0000000000..85a6158a2f --- /dev/null +++ b/test/functional/test_framework/key.py @@ -0,0 +1,232 @@ +# Copyright (c) 2011 Sam Rushing +"""ECC secp256k1 OpenSSL wrapper. + +WARNING: This module does not mlock() secrets; your private keys may end up on +disk in swap! Use with caution! + +This file is modified from python-bitcoinlib. +""" + +import ctypes +import ctypes.util +import hashlib +import sys + +ssl = ctypes.cdll.LoadLibrary(ctypes.util.find_library ('ssl') or 'libeay32') + +ssl.BN_new.restype = ctypes.c_void_p +ssl.BN_new.argtypes = [] + +ssl.BN_bin2bn.restype = ctypes.c_void_p +ssl.BN_bin2bn.argtypes = [ctypes.c_char_p, ctypes.c_int, ctypes.c_void_p] + +ssl.BN_CTX_free.restype = None +ssl.BN_CTX_free.argtypes = [ctypes.c_void_p] + +ssl.BN_CTX_new.restype = ctypes.c_void_p +ssl.BN_CTX_new.argtypes = [] + +ssl.ECDH_compute_key.restype = ctypes.c_int +ssl.ECDH_compute_key.argtypes = [ctypes.c_void_p, ctypes.c_int, ctypes.c_void_p, ctypes.c_void_p] + +ssl.ECDSA_sign.restype = ctypes.c_int +ssl.ECDSA_sign.argtypes = [ctypes.c_int, ctypes.c_void_p, ctypes.c_int, ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p] + +ssl.ECDSA_verify.restype = ctypes.c_int +ssl.ECDSA_verify.argtypes = [ctypes.c_int, ctypes.c_void_p, ctypes.c_int, ctypes.c_void_p, ctypes.c_int, ctypes.c_void_p] + +ssl.EC_KEY_free.restype = None +ssl.EC_KEY_free.argtypes = [ctypes.c_void_p] + +ssl.EC_KEY_new_by_curve_name.restype = ctypes.c_void_p +ssl.EC_KEY_new_by_curve_name.argtypes = [ctypes.c_int] + +ssl.EC_KEY_get0_group.restype = ctypes.c_void_p +ssl.EC_KEY_get0_group.argtypes = [ctypes.c_void_p] + +ssl.EC_KEY_get0_public_key.restype = ctypes.c_void_p +ssl.EC_KEY_get0_public_key.argtypes = [ctypes.c_void_p] + +ssl.EC_KEY_set_private_key.restype = ctypes.c_int +ssl.EC_KEY_set_private_key.argtypes = [ctypes.c_void_p, ctypes.c_void_p] + +ssl.EC_KEY_set_conv_form.restype = None +ssl.EC_KEY_set_conv_form.argtypes = [ctypes.c_void_p, ctypes.c_int] + +ssl.EC_KEY_set_public_key.restype = ctypes.c_int +ssl.EC_KEY_set_public_key.argtypes = [ctypes.c_void_p, ctypes.c_void_p] + +ssl.i2o_ECPublicKey.restype = ctypes.c_void_p +ssl.i2o_ECPublicKey.argtypes = [ctypes.c_void_p, ctypes.c_void_p] + +ssl.EC_POINT_new.restype = ctypes.c_void_p +ssl.EC_POINT_new.argtypes = [ctypes.c_void_p] + +ssl.EC_POINT_free.restype = None +ssl.EC_POINT_free.argtypes = [ctypes.c_void_p] + +ssl.EC_POINT_mul.restype = ctypes.c_int +ssl.EC_POINT_mul.argtypes = [ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p, ctypes.c_void_p] + +# this specifies the curve used with ECDSA. +NID_secp256k1 = 714 # from openssl/obj_mac.h + +SECP256K1_ORDER = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 +SECP256K1_ORDER_HALF = SECP256K1_ORDER // 2 + +# Thx to Sam Devlin for the ctypes magic 64-bit fix. +def _check_result(val, func, args): + if val == 0: + raise ValueError + else: + return ctypes.c_void_p (val) + +ssl.EC_KEY_new_by_curve_name.restype = ctypes.c_void_p +ssl.EC_KEY_new_by_curve_name.errcheck = _check_result + +class CECKey(object): + """Wrapper around OpenSSL's EC_KEY""" + + POINT_CONVERSION_COMPRESSED = 2 + POINT_CONVERSION_UNCOMPRESSED = 4 + + def __init__(self): + self.k = ssl.EC_KEY_new_by_curve_name(NID_secp256k1) + + def __del__(self): + if ssl: + ssl.EC_KEY_free(self.k) + self.k = None + + def set_secretbytes(self, secret): + priv_key = ssl.BN_bin2bn(secret, 32, ssl.BN_new()) + group = ssl.EC_KEY_get0_group(self.k) + pub_key = ssl.EC_POINT_new(group) + ctx = ssl.BN_CTX_new() + if not ssl.EC_POINT_mul(group, pub_key, priv_key, None, None, ctx): + raise ValueError("Could not derive public key from the supplied secret.") + ssl.EC_POINT_mul(group, pub_key, priv_key, None, None, ctx) + ssl.EC_KEY_set_private_key(self.k, priv_key) + ssl.EC_KEY_set_public_key(self.k, pub_key) + ssl.EC_POINT_free(pub_key) + ssl.BN_CTX_free(ctx) + return self.k + + def set_privkey(self, key): + self.mb = ctypes.create_string_buffer(key) + return ssl.d2i_ECPrivateKey(ctypes.byref(self.k), ctypes.byref(ctypes.pointer(self.mb)), len(key)) + + def set_pubkey(self, key): + self.mb = ctypes.create_string_buffer(key) + return ssl.o2i_ECPublicKey(ctypes.byref(self.k), ctypes.byref(ctypes.pointer(self.mb)), len(key)) + + def get_privkey(self): + size = ssl.i2d_ECPrivateKey(self.k, 0) + mb_pri = ctypes.create_string_buffer(size) + ssl.i2d_ECPrivateKey(self.k, ctypes.byref(ctypes.pointer(mb_pri))) + return mb_pri.raw + + def get_pubkey(self): + size = ssl.i2o_ECPublicKey(self.k, 0) + mb = ctypes.create_string_buffer(size) + ssl.i2o_ECPublicKey(self.k, ctypes.byref(ctypes.pointer(mb))) + return mb.raw + + def get_raw_ecdh_key(self, other_pubkey): + ecdh_keybuffer = ctypes.create_string_buffer(32) + r = ssl.ECDH_compute_key(ctypes.pointer(ecdh_keybuffer), 32, + ssl.EC_KEY_get0_public_key(other_pubkey.k), + self.k, 0) + if r != 32: + raise Exception('CKey.get_ecdh_key(): ECDH_compute_key() failed') + return ecdh_keybuffer.raw + + def get_ecdh_key(self, other_pubkey, kdf=lambda k: hashlib.sha256(k).digest()): + # FIXME: be warned it's not clear what the kdf should be as a default + r = self.get_raw_ecdh_key(other_pubkey) + return kdf(r) + + def sign(self, hash, low_s = True): + # FIXME: need unit tests for below cases + if not isinstance(hash, bytes): + raise TypeError('Hash must be bytes instance; got %r' % hash.__class__) + if len(hash) != 32: + raise ValueError('Hash must be exactly 32 bytes long') + + sig_size0 = ctypes.c_uint32() + sig_size0.value = ssl.ECDSA_size(self.k) + mb_sig = ctypes.create_string_buffer(sig_size0.value) + result = ssl.ECDSA_sign(0, hash, len(hash), mb_sig, ctypes.byref(sig_size0), self.k) + assert 1 == result + assert mb_sig.raw[0] == 0x30 + assert mb_sig.raw[1] == sig_size0.value - 2 + total_size = mb_sig.raw[1] + assert mb_sig.raw[2] == 2 + r_size = mb_sig.raw[3] + assert mb_sig.raw[4 + r_size] == 2 + s_size = mb_sig.raw[5 + r_size] + s_value = int.from_bytes(mb_sig.raw[6+r_size:6+r_size+s_size], byteorder='big') + if (not low_s) or s_value <= SECP256K1_ORDER_HALF: + return mb_sig.raw[:sig_size0.value] + else: + low_s_value = SECP256K1_ORDER - s_value + low_s_bytes = (low_s_value).to_bytes(33, byteorder='big') + while len(low_s_bytes) > 1 and low_s_bytes[0] == 0 and low_s_bytes[1] < 0x80: + low_s_bytes = low_s_bytes[1:] + new_s_size = len(low_s_bytes) + new_total_size_byte = (total_size + new_s_size - s_size).to_bytes(1,byteorder='big') + new_s_size_byte = (new_s_size).to_bytes(1,byteorder='big') + return b'\x30' + new_total_size_byte + mb_sig.raw[2:5+r_size] + new_s_size_byte + low_s_bytes + + def verify(self, hash, sig): + """Verify a DER signature""" + return ssl.ECDSA_verify(0, hash, len(hash), sig, len(sig), self.k) == 1 + + def set_compressed(self, compressed): + if compressed: + form = self.POINT_CONVERSION_COMPRESSED + else: + form = self.POINT_CONVERSION_UNCOMPRESSED + ssl.EC_KEY_set_conv_form(self.k, form) + + +class CPubKey(bytes): + """An encapsulated public key + + Attributes: + + is_valid - Corresponds to CPubKey.IsValid() + is_fullyvalid - Corresponds to CPubKey.IsFullyValid() + is_compressed - Corresponds to CPubKey.IsCompressed() + """ + + def __new__(cls, buf, _cec_key=None): + self = super(CPubKey, cls).__new__(cls, buf) + if _cec_key is None: + _cec_key = CECKey() + self._cec_key = _cec_key + self.is_fullyvalid = _cec_key.set_pubkey(self) != 0 + return self + + @property + def is_valid(self): + return len(self) > 0 + + @property + def is_compressed(self): + return len(self) == 33 + + def verify(self, hash, sig): + return self._cec_key.verify(hash, sig) + + def __str__(self): + return repr(self) + + def __repr__(self): + # Always have represent as b'<secret>' so test cases don't have to + # change for py2/3 + if sys.version > '3': + return '%s(%s)' % (self.__class__.__name__, super(CPubKey, self).__repr__()) + else: + return '%s(b%s)' % (self.__class__.__name__, super(CPubKey, self).__repr__()) + |