prepare for separation of ecc module:

- move encrypt/sign functions elsewhere
- remove local dependencies in ecc.py, ecc_fast.py (except logging)

electrum/bitcoin.py

@@ -769,7 +769,7 @@ def taproot_tweak_pubkey(pubkey32: bytes, h: bytes) -> Tuple[int, bytes]:
     assert len(pubkey32) == 32, len(pubkey32)
     int_from_bytes = lambda x: int.from_bytes(x, byteorder="big", signed=False)
 
-    tweak = int_from_bytes(ecc.bip340_tagged_hash(b"TapTweak", pubkey32 + h))
+    tweak = int_from_bytes(bip340_tagged_hash(b"TapTweak", pubkey32 + h))
     if tweak >= ecc.CURVE_ORDER:
         raise ValueError
     P = ecc.ECPubkey(b"\x02" + pubkey32)
@@ -786,7 +786,7 @@ def taproot_tweak_seckey(seckey0: bytes, h: bytes) -> bytes:
     P = ecc.ECPrivkey(seckey0)
     seckey = P.secret_scalar if P.has_even_y() else ecc.CURVE_ORDER - P.secret_scalar
     pubkey32 = P.get_public_key_bytes(compressed=True)[1:]
-    tweak = int_from_bytes(ecc.bip340_tagged_hash(b"TapTweak", pubkey32 + h))
+    tweak = int_from_bytes(bip340_tagged_hash(b"TapTweak", pubkey32 + h))
     if tweak >= ecc.CURVE_ORDER:
         raise ValueError
     return int.to_bytes((seckey + tweak) % ecc.CURVE_ORDER, length=32, byteorder="big", signed=False)
@@ -798,18 +798,21 @@ def taproot_tweak_seckey(seckey0: bytes, h: bytes) -> bytes:
 TapTreeLeaf = Tuple[int, bytes]
 TapTree = Union[TapTreeLeaf, Sequence['TapTree']]
 
+def bip340_tagged_hash(tag: bytes, msg: bytes) -> bytes:
+    # note: _libsecp256k1.secp256k1_tagged_sha256 benchmarks about 70% slower than this (on my machine)
+    return sha256(sha256(tag) + sha256(tag) + msg)
 
 def taproot_tree_helper(script_tree: TapTree):
     if isinstance(script_tree, tuple):
         leaf_version, script = script_tree
-        h = ecc.bip340_tagged_hash(b"TapLeaf", bytes([leaf_version]) + witness_push(script))
+        h = bip340_tagged_hash(b"TapLeaf", bytes([leaf_version]) + witness_push(script))
         return ([((leaf_version, script), bytes())], h)
     left, left_h = taproot_tree_helper(script_tree[0])
     right, right_h = taproot_tree_helper(script_tree[1])
     ret = [(l, c + right_h) for l, c in left] + [(l, c + left_h) for l, c in right]
     if right_h < left_h:
         left_h, right_h = right_h, left_h
-    return (ret, ecc.bip340_tagged_hash(b"TapBranch", left_h + right_h))
+    return (ret, bip340_tagged_hash(b"TapBranch", left_h + right_h))
 
 
 def taproot_output_script(internal_pubkey: bytes, *, script_tree: Optional[TapTree]) -> bytes:
@@ -838,3 +841,38 @@ def control_block_for_taproot_script_spend(
     pubkey_data = bytes([output_pubkey_y_parity + leaf_version]) + internal_pubkey
     control_block = pubkey_data + merkle_path
     return (leaf_script, control_block)
+
+
+# user message signing
+def usermessage_magic(message: bytes) -> bytes:
+    from .bitcoin import var_int
+    length = var_int(len(message))
+    return b"\x18Bitcoin Signed Message:\n" + length + message
+
+def ecdsa_sign_usermessage(ec_privkey, message: Union[bytes, str], *, is_compressed: bool) -> bytes:
+    message = to_bytes(message, 'utf8')
+    msg32 = sha256d(usermessage_magic(message))
+    return ec_privkey.ecdsa_sign_recoverable(msg32, is_compressed=is_compressed)
+
+def verify_usermessage_with_address(address: str, sig65: bytes, message: bytes, *, net=None) -> bool:
+    from .bitcoin import pubkey_to_address
+    from .ecc import ECPubkey
+    assert_bytes(sig65, message)
+    if net is None: net = constants.net
+    h = sha256d(usermessage_magic(message))
+    try:
+        public_key, compressed, txin_type_guess = ECPubkey.from_ecdsa_sig65(sig65, h)
+    except Exception as e:
+        return False
+    # check public key using the address
+    pubkey_hex = public_key.get_public_key_hex(compressed)
+    txin_types = (txin_type_guess,) if txin_type_guess else ('p2pkh', 'p2wpkh', 'p2wpkh-p2sh')
+    for txin_type in txin_types:
+        addr = pubkey_to_address(txin_type, pubkey_hex, net=net)
+        if address == addr:
+            break
+    else:
+        return False
+    # check message
+    # note: `$ bitcoin-cli verifymessage` does NOT enforce the low-S rule for ecdsa sigs
+    return public_key.ecdsa_verify(sig65[1:], h, enforce_low_s=False)

electrum/commands.py

@@ -716,7 +716,7 @@ class Commands:
         """Verify a signature."""
         sig = base64.b64decode(signature)
         message = util.to_bytes(message)
-        return ecc.verify_usermessage_with_address(address, sig, message)
+        return bitcoin.verify_usermessage_with_address(address, sig, message)
 
     @command('wp')
     async def payto(self, destination, amount, fee=None, feerate=None, from_addr=None, from_coins=None, change_addr=None,
@@ -910,7 +910,7 @@ class Commands:
         except TypeError:
             raise UserFacingException(f"message must be a string-like object instead of {repr(message)}")
         public_key = ecc.ECPubkey(bfh(pubkey))
-        encrypted = public_key.encrypt_message(message)
+        encrypted = crypto.ecies_encrypt_message(public_key, message)
         return encrypted.decode('utf-8')
 
     @command('wp')

electrum/crypto.py

@@ -34,7 +34,7 @@ from typing import Union, Mapping, Optional
 from .util import assert_bytes, InvalidPassword, to_bytes, to_string, WalletFileException, versiontuple
 from .i18n import _
 from .logging import get_logger
-
+from . import ecc
 
 _logger = get_logger(__name__)
 
@@ -443,3 +443,41 @@ def chacha20_decrypt(*, key: bytes, nonce: bytes, data: bytes) -> bytes:
         decryptor = cipher.decryptor()
         return decryptor.update(data)
     raise Exception("no chacha20 backend found")
+
+
+def ecies_encrypt_message(ec_pubkey, message: bytes, *, magic: bytes = b'BIE1') -> bytes:
+    """
+        ECIES encryption/decryption methods; AES-128-CBC with PKCS7 is used as the cipher; hmac-sha256 is used as the mac
+    """
+    assert_bytes(message)
+    ephemeral = ecc.ECPrivkey.generate_random_key()
+    ecdh_key = (ec_pubkey * ephemeral.secret_scalar).get_public_key_bytes(compressed=True)
+    key = hashlib.sha512(ecdh_key).digest()
+    iv, key_e, key_m = key[0:16], key[16:32], key[32:]
+    ciphertext = aes_encrypt_with_iv(key_e, iv, message)
+    ephemeral_pubkey = ephemeral.get_public_key_bytes(compressed=True)
+    encrypted = magic + ephemeral_pubkey + ciphertext
+    mac = hmac_oneshot(key_m, encrypted, hashlib.sha256)
+    return base64.b64encode(encrypted + mac)
+
+
+def ecies_decrypt_message(ec_privkey, encrypted: Union[str, bytes], *, magic: bytes=b'BIE1') -> bytes:
+    encrypted = base64.b64decode(encrypted)  # type: bytes
+    if len(encrypted) < 85:
+        raise Exception('invalid ciphertext: length')
+    magic_found = encrypted[:4]
+    ephemeral_pubkey_bytes = encrypted[4:37]
+    ciphertext = encrypted[37:-32]
+    mac = encrypted[-32:]
+    if magic_found != magic:
+        raise Exception('invalid ciphertext: invalid magic bytes')
+    try:
+        ephemeral_pubkey = ecc.ECPubkey(ephemeral_pubkey_bytes)
+    except ecc.InvalidECPointException as e:
+        raise Exception('invalid ciphertext: invalid ephemeral pubkey') from e
+    ecdh_key = (ephemeral_pubkey * ec_privkey.secret_scalar).get_public_key_bytes(compressed=True)
+    key = hashlib.sha512(ecdh_key).digest()
+    iv, key_e, key_m = key[0:16], key[16:32], key[32:]
+    if mac != hmac_oneshot(key_m, encrypted[:-32], hashlib.sha256):
+        raise InvalidPassword()
+    return aes_decrypt_with_iv(key_e, iv, ciphertext)

electrum/ecc.py

@@ -26,20 +26,17 @@
 import base64
 import hashlib
 import functools
+import secrets
 from typing import Union, Tuple, Optional
 from ctypes import (
     byref, c_char_p, c_size_t, create_string_buffer, cast,
 )
 
-from .util import bfh, assert_bytes, to_bytes, InvalidPassword, profiler, randrange
-from .crypto import (sha256, sha256d, aes_encrypt_with_iv, aes_decrypt_with_iv, hmac_oneshot)
-from . import constants
-from .logging import get_logger
 from . import ecc_fast
 from .ecc_fast import _libsecp256k1, SECP256K1_EC_UNCOMPRESSED, LibModuleMissing
 
-_logger = get_logger(__name__)
+def assert_bytes(x):
-
+    assert isinstance(x, (bytes, bytearray))
 
 # Some unit tests need to create ECDSA sigs without grinding the R value (and just use RFC6979).
 # see https://github.com/bitcoin/bitcoin/pull/13666
@@ -382,23 +379,6 @@ class ECPubkey(object):
             return False
         return True
 
-    def encrypt_message(self, message: bytes, *, magic: bytes = b'BIE1') -> bytes:
-        """
-        ECIES encryption/decryption methods; AES-128-CBC with PKCS7 is used as the cipher; hmac-sha256 is used as the mac
-        """
-        assert_bytes(message)
-
-        ephemeral = ECPrivkey.generate_random_key()
-        ecdh_key = (self * ephemeral.secret_scalar).get_public_key_bytes(compressed=True)
-        key = hashlib.sha512(ecdh_key).digest()
-        iv, key_e, key_m = key[0:16], key[16:32], key[32:]
-        ciphertext = aes_encrypt_with_iv(key_e, iv, message)
-        ephemeral_pubkey = ephemeral.get_public_key_bytes(compressed=True)
-        encrypted = magic + ephemeral_pubkey + ciphertext
-        mac = hmac_oneshot(key_m, encrypted, hashlib.sha256)
-
-        return base64.b64encode(encrypted + mac)
-
     @classmethod
     def order(cls) -> int:
         return CURVE_ORDER
@@ -424,34 +404,6 @@ CURVE_ORDER = 0xFFFFFFFF_FFFFFFFF_FFFFFFFF_FFFFFFFE_BAAEDCE6_AF48A03B_BFD25E8C_D
 POINT_AT_INFINITY = ECPubkey(None)
 
 
-def usermessage_magic(message: bytes) -> bytes:
-    from .bitcoin import var_int
-    length = var_int(len(message))
-    return b"\x18Bitcoin Signed Message:\n" + length + message
-
-
-def verify_usermessage_with_address(address: str, sig65: bytes, message: bytes, *, net=None) -> bool:
-    from .bitcoin import pubkey_to_address
-    assert_bytes(sig65, message)
-    if net is None: net = constants.net
-    h = sha256d(usermessage_magic(message))
-    try:
-        public_key, compressed, txin_type_guess = ECPubkey.from_ecdsa_sig65(sig65, h)
-    except Exception as e:
-        return False
-    # check public key using the address
-    pubkey_hex = public_key.get_public_key_hex(compressed)
-    txin_types = (txin_type_guess,) if txin_type_guess else ('p2pkh', 'p2wpkh', 'p2wpkh-p2sh')
-    for txin_type in txin_types:
-        addr = pubkey_to_address(txin_type, pubkey_hex, net=net)
-        if address == addr:
-            break
-    else:
-        return False
-    # check message
-    # note: `$ bitcoin-cli verifymessage` does NOT enforce the low-S rule for ecdsa sigs
-    return public_key.ecdsa_verify(sig65[1:], h, enforce_low_s=False)
-
 
 def is_secret_within_curve_range(secret: Union[int, bytes]) -> bool:
     if isinstance(secret, bytes):
@@ -499,7 +451,7 @@ class ECPrivkey(ECPubkey):
 
     @classmethod
     def generate_random_key(cls) -> 'ECPrivkey':
-        randint = randrange(CURVE_ORDER)
+        randint = secrets.randbelow(CURVE_ORDER - 1) + 1
         ephemeral_exponent = int.to_bytes(randint, length=32, byteorder='big', signed=False)
         return ECPrivkey(ephemeral_exponent)
 
@@ -592,31 +544,6 @@ class ECPrivkey(ECPubkey):
         sig65, recid = bruteforce_recid(sig64)
         return sig65
 
-    def ecdsa_sign_usermessage(self, message: Union[bytes, str], *, is_compressed: bool) -> bytes:
-        message = to_bytes(message, 'utf8')
-        msg32 = sha256d(usermessage_magic(message))
-        return self.ecdsa_sign_recoverable(msg32, is_compressed=is_compressed)
-
-    def decrypt_message(self, encrypted: Union[str, bytes], *, magic: bytes=b'BIE1') -> bytes:
-        encrypted = base64.b64decode(encrypted)  # type: bytes
-        if len(encrypted) < 85:
-            raise Exception('invalid ciphertext: length')
-        magic_found = encrypted[:4]
-        ephemeral_pubkey_bytes = encrypted[4:37]
-        ciphertext = encrypted[37:-32]
-        mac = encrypted[-32:]
-        if magic_found != magic:
-            raise Exception('invalid ciphertext: invalid magic bytes')
-        try:
-            ephemeral_pubkey = ECPubkey(ephemeral_pubkey_bytes)
-        except InvalidECPointException as e:
-            raise Exception('invalid ciphertext: invalid ephemeral pubkey') from e
-        ecdh_key = (ephemeral_pubkey * self.secret_scalar).get_public_key_bytes(compressed=True)
-        key = hashlib.sha512(ecdh_key).digest()
-        iv, key_e, key_m = key[0:16], key[16:32], key[32:]
-        if mac != hmac_oneshot(key_m, encrypted[:-32], hashlib.sha256):
-            raise InvalidPassword()
-        return aes_decrypt_with_iv(key_e, iv, ciphertext)
 
 
 def construct_ecdsa_sig65(sig64: bytes, recid: int, *, is_compressed: bool) -> bytes:
@@ -624,6 +551,3 @@ def construct_ecdsa_sig65(sig64: bytes, recid: int, *, is_compressed: bool) -> b
     return bytes([27 + recid + comp]) + sig64
 
 
-def bip340_tagged_hash(tag: bytes, msg: bytes) -> bytes:
-    # note: _libsecp256k1.secp256k1_tagged_sha256 benchmarks about 70% slower than this (on my machine)
-    return sha256(sha256(tag) + sha256(tag) + msg)

electrum/gui/qml/qedaemon.py

@@ -12,7 +12,7 @@ from electrum.util import WalletFileException, standardize_path, InvalidPassword
 from electrum.plugin import run_hook
 from electrum.lnchannel import ChannelState
 from electrum.bitcoin import is_address
-from electrum.ecc import verify_usermessage_with_address
+from electrum.bitcoin import verify_usermessage_with_address
 from electrum.storage import StorageReadWriteError
 
 from .auth import AuthMixin, auth_protect

electrum/gui/qt/main_window.py

@@ -1993,7 +1993,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger, QtEventListener):
         try:
             # This can throw on invalid base64
             sig = base64.b64decode(str(signature.toPlainText()))
-            verified = ecc.verify_usermessage_with_address(address, sig, message)
+            verified = bitcoin.verify_usermessage_with_address(address, sig, message)
         except Exception as e:
             verified = False
         if verified:
@@ -2057,6 +2057,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger, QtEventListener):
         self.thread.add(task, on_success=setText)
 
     def do_encrypt(self, message_e, pubkey_e, encrypted_e):
+        from electrum import crypto
         message = message_e.toPlainText()
         message = message.encode('utf-8')
         try:
@@ -2065,7 +2066,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger, QtEventListener):
             self.logger.exception('Invalid Public key')
             self.show_warning(_('Invalid Public key'))
             return
-        encrypted = public_key.encrypt_message(message)
+        encrypted = crypto.ecies_encrypt_message(public_key, message)
         encrypted_e.setText(encrypted.decode('ascii'))
 
     def encrypt_message(self, address=''):

electrum/keystore.py

@@ -41,6 +41,7 @@ from .bip32 import (convert_bip32_strpath_to_intpath, BIP32_PRIME,
                     KeyOriginInfo)
 from .descriptor import PubkeyProvider
 from .ecc import string_to_number
+from . import crypto
 from .crypto import (pw_decode, pw_encode, sha256, sha256d, PW_HASH_VERSION_LATEST,
                      SUPPORTED_PW_HASH_VERSIONS, UnsupportedPasswordHashVersion, hash_160,
                      CiphertextFormatError)
@@ -223,12 +224,12 @@ class Software_KeyStore(KeyStore):
     def sign_message(self, sequence, message, password, *, script_type=None) -> bytes:
         privkey, compressed = self.get_private_key(sequence, password)
         key = ecc.ECPrivkey(privkey)
-        return key.ecdsa_sign_usermessage(message, is_compressed=compressed)
+        return bitcoin.ecdsa_sign_usermessage(key, message, is_compressed=compressed)
 
     def decrypt_message(self, sequence, message, password) -> bytes:
         privkey, compressed = self.get_private_key(sequence, password)
         ec = ecc.ECPrivkey(privkey)
-        decrypted = ec.decrypt_message(message)
+        decrypted = crypto.ecies_decrypt_message(ec, message)
         return decrypted
 
     def sign_transaction(self, tx, password):

electrum/paymentrequest.py

@@ -235,7 +235,7 @@ class PaymentRequest:
             address = info.get('address')
             pr.signature = b''
             message = pr.SerializeToString()
-            if ecc.verify_usermessage_with_address(address, sig, message):
+            if bitcoin.verify_usermessage_with_address(address, sig, message):
                 self._verified_success_msg = 'Verified with DNSSEC'
                 self._verified_success = True
                 return True
@@ -356,7 +356,7 @@ def sign_request_with_alias(pr, alias, alias_privkey):
     message = pr.SerializeToString()
     ec_key = ecc.ECPrivkey(alias_privkey)
     compressed = bitcoin.is_compressed_privkey(alias_privkey)
-    pr.signature = ec_key.ecdsa_sign_usermessage(message, is_compressed=compressed)
+    pr.signature = bitcoin.ecdsa_sign_usermessage(ec_key, message, is_compressed=compressed)
 
 
 def verify_cert_chain(chain):

electrum/storage.py

@@ -31,7 +31,7 @@ import zlib
 from enum import IntEnum
 from typing import Optional
 
-from . import ecc
+from . import ecc, crypto
 from .util import (profiler, InvalidPassword, WalletFileException, bfh, standardize_path,
                    test_read_write_permissions, os_chmod)
 
@@ -192,7 +192,7 @@ class WalletStorage(Logger):
         ec_key = self.get_eckey_from_password(password)
         if self.raw:
             enc_magic = self._get_encryption_magic()
-            s = zlib.decompress(ec_key.decrypt_message(self.raw, magic=enc_magic))
+            s = zlib.decompress(crypto.ecies_decrypt_message(ec_key, self.raw, magic=enc_magic))
             s = s.decode('utf8')
         else:
             s = ''
@@ -207,7 +207,7 @@ class WalletStorage(Logger):
             c = zlib.compress(s, level=zlib.Z_BEST_SPEED)
             enc_magic = self._get_encryption_magic()
             public_key = ecc.ECPubkey(bfh(self.pubkey))
-            s = public_key.encrypt_message(c, magic=enc_magic)
+            s = crypto.ecies_encrypt_message(public_key, c, magic=enc_magic)
             s = s.decode('utf8')
         return s
 

electrum/transaction.py

@@ -2309,7 +2309,7 @@ class PartialTransaction(Transaction):
             merkle_root = txin.tap_merkle_root or bytes()
             output_privkey_bytes = taproot_tweak_seckey(privkey_bytes, merkle_root)
             output_privkey = ecc.ECPrivkey(output_privkey_bytes)
-            msg_hash = ecc.bip340_tagged_hash(b"TapSighash", pre_hash)
+            msg_hash = bitcoin.bip340_tagged_hash(b"TapSighash", pre_hash)
             sig = output_privkey.schnorr_sign(msg_hash)
             sighash = txin.sighash if txin.sighash is not None else Sighash.DEFAULT
         else:

tests/test_bitcoin.py

@@ -23,12 +23,12 @@ from electrum.bip32 import (BIP32Node, convert_bip32_intpath_to_strpath,
                             is_xpub, convert_bip32_strpath_to_intpath,
                             normalize_bip32_derivation, is_all_public_derivation)
 from electrum.crypto import sha256d, SUPPORTED_PW_HASH_VERSIONS
-from electrum import ecc, crypto, constants
+from electrum import ecc, crypto, constants, bitcoin
 from electrum.util import bfh, InvalidPassword, randrange
 from electrum.storage import WalletStorage
 from electrum.keystore import xtype_from_derivation
 
-from electrum import ecc_fast
+from electrum import ecc_fast, crypto
 
 from . import ElectrumTestCase
 from . import FAST_TESTS
@@ -182,16 +182,16 @@ class Test_bitcoin(ElectrumTestCase):
         eck = ecc.ECPrivkey.from_secret_scalar(pvk)
 
         #print "Compressed public key  ", pubkey_c.encode('hex')
-        enc = ecc.ECPubkey(pubkey_c).encrypt_message(message)
+        enc = crypto.ecies_encrypt_message(ecc.ECPubkey(pubkey_c), message)
-        dec = eck.decrypt_message(enc)
+        dec = crypto.ecies_decrypt_message(eck, enc)
         self.assertEqual(message, dec)
 
         #print "Uncompressed public key", pubkey_u.encode('hex')
         #enc2 = EC_KEY.encrypt_message(message, pubkey_u)
-        dec2 = eck.decrypt_message(enc)
+        dec2 = crypto.ecies_decrypt_message(eck, enc)
         self.assertEqual(message, dec2)
 
-        msg32 = sha256d(ecc.usermessage_magic(message))
+        msg32 = sha256d(bitcoin.usermessage_magic(message))
         sig65 = eck.ecdsa_sign_recoverable(msg32, is_compressed=True)
         self.assertTrue(eck.ecdsa_verify_recoverable(sig65, msg32))
 
@@ -226,7 +226,7 @@ class Test_bitcoin(ElectrumTestCase):
     def sign_message_with_wif_privkey(wif_privkey: str, msg: bytes) -> bytes:
         txin_type, privkey, compressed = deserialize_privkey(wif_privkey)
         key = ecc.ECPrivkey(privkey)
-        return key.ecdsa_sign_usermessage(msg, is_compressed=compressed)
+        return bitcoin.ecdsa_sign_usermessage(key, msg, is_compressed=compressed)
 
     def test_signmessage_legacy_address(self):
         msg1 = b'Chancellor on brink of second bailout for banks'
@@ -245,11 +245,11 @@ class Test_bitcoin(ElectrumTestCase):
         self.assertEqual(sig1_b64, b'Hzsu0U/THAsPz/MSuXGBKSULz2dTfmrg1NsAhFp+wH5aKfmX4Db7ExLGa7FGn0m6Mf43KsbEOWpvUUUBTM3Uusw=')
         self.assertEqual(sig2_b64, b'HBQdYfv7kOrxmRewLJnG7sV6KlU71O04hUnE4tai97p7Pg+D+yKaWXsdGgHTrKw90caQMo/D6b//qX50ge9P9iI=')
 
-        self.assertTrue(ecc.verify_usermessage_with_address(addr1, sig1, msg1))
+        self.assertTrue(bitcoin.verify_usermessage_with_address(addr1, sig1, msg1))
-        self.assertTrue(ecc.verify_usermessage_with_address(addr2, sig2, msg2))
+        self.assertTrue(bitcoin.verify_usermessage_with_address(addr2, sig2, msg2))
 
-        self.assertFalse(ecc.verify_usermessage_with_address(addr1, b'wrong', msg1))
+        self.assertFalse(bitcoin.verify_usermessage_with_address(addr1, b'wrong', msg1))
-        self.assertFalse(ecc.verify_usermessage_with_address(addr1, sig2, msg1))
+        self.assertFalse(bitcoin.verify_usermessage_with_address(addr1, sig2, msg1))
 
     def test_signmessage_low_s(self):
         """`$ bitcoin-cli verifymessage` does NOT enforce the low-S rule for ecdsa sigs. This tests we do the same."""
@@ -257,8 +257,8 @@ class Test_bitcoin(ElectrumTestCase):
         sig_low_s = b'Hzsu0U/THAsPz/MSuXGBKSULz2dTfmrg1NsAhFp+wH5aKfmX4Db7ExLGa7FGn0m6Mf43KsbEOWpvUUUBTM3Uusw='
         sig_high_s = b'IDsu0U/THAsPz/MSuXGBKSULz2dTfmrg1NsAhFp+wH5a1gZoH8kE7O05lE65YLZFzLx3sh/rDzXMbo1dQAJhhnU='
         msg = b'Chancellor on brink of second bailout for banks'
-        self.assertTrue(ecc.verify_usermessage_with_address(address=addr, sig65=base64.b64decode(sig_low_s), message=msg))
+        self.assertTrue(bitcoin.verify_usermessage_with_address(address=addr, sig65=base64.b64decode(sig_low_s), message=msg))
-        self.assertTrue(ecc.verify_usermessage_with_address(address=addr, sig65=base64.b64decode(sig_high_s), message=msg))
+        self.assertTrue(bitcoin.verify_usermessage_with_address(address=addr, sig65=base64.b64decode(sig_high_s), message=msg))
 
     def test_signmessage_segwit_witness_v0_address(self):
         msg = b'Electrum'
@@ -266,14 +266,14 @@ class Test_bitcoin(ElectrumTestCase):
         sig1 = self.sign_message_with_wif_privkey("p2wpkh-p2sh:L1cgMEnShp73r9iCukoPE3MogLeueNYRD9JVsfT1zVHyPBR3KqBY", msg)
         addr1 = "3DYoBqQ5N6dADzyQjy9FT1Ls4amiYVaqTG"
         self.assertEqual(base64.b64encode(sig1), b'HyFaND+87TtVbRhkTfT3mPNBCQcJ32XXtNZGW8sFldJsNpOPCegEmdcCf5Thy18hdMH88GLxZLkOby/EwVUuSeA=')
-        self.assertTrue(ecc.verify_usermessage_with_address(addr1, sig1, msg))
+        self.assertTrue(bitcoin.verify_usermessage_with_address(addr1, sig1, msg))
-        self.assertFalse(ecc.verify_usermessage_with_address(addr1, sig1, b'heyheyhey'))
+        self.assertFalse(bitcoin.verify_usermessage_with_address(addr1, sig1, b'heyheyhey'))
         # p2wpkh
         sig2 = self.sign_message_with_wif_privkey("p2wpkh:L1cgMEnShp73r9iCukoPE3MogLeueNYRD9JVsfT1zVHyPBR3KqBY", msg)
         addr2 = "bc1qq2tmmcngng78nllq2pvrkchcdukemtj56uyue0"
         self.assertEqual(base64.b64encode(sig2), b'HyFaND+87TtVbRhkTfT3mPNBCQcJ32XXtNZGW8sFldJsNpOPCegEmdcCf5Thy18hdMH88GLxZLkOby/EwVUuSeA=')
-        self.assertTrue(ecc.verify_usermessage_with_address(addr2, sig2, msg))
+        self.assertTrue(bitcoin.verify_usermessage_with_address(addr2, sig2, msg))
-        self.assertFalse(ecc.verify_usermessage_with_address(addr2, sig2, b'heyheyhey'))
+        self.assertFalse(bitcoin.verify_usermessage_with_address(addr2, sig2, b'heyheyhey'))
 
     def test_signmessage_segwit_witness_v0_address_test_we_also_accept_sigs_from_trezor(self):
         """Trezor and some other projects use a slightly different scheme for message-signing
@@ -286,20 +286,23 @@ class Test_bitcoin(ElectrumTestCase):
         addr2 = "bc1qannfxke2tfd4l7vhepehpvt05y83v3qsf6nfkk"
         sig1 = bytes.fromhex("23744de4516fac5c140808015664516a32fead94de89775cec7e24dbc24fe133075ac09301c4cc8e197bea4b6481661d5b8e9bf19d8b7b8a382ecdb53c2ee0750d")
         sig2 = bytes.fromhex("28b55d7600d9e9a7e2a49155ddf3cfdb8e796c207faab833010fa41fb7828889bc47cf62348a7aaa0923c0832a589fab541e8f12eb54fb711c90e2307f0f66b194")
-        self.assertTrue(ecc.verify_usermessage_with_address(address=addr1, sig65=sig1, message=msg))
+        self.assertTrue(bitcoin.verify_usermessage_with_address(address=addr1, sig65=sig1, message=msg))
-        self.assertTrue(ecc.verify_usermessage_with_address(address=addr2, sig65=sig2, message=msg))
+        self.assertTrue(bitcoin.verify_usermessage_with_address(address=addr2, sig65=sig2, message=msg))
         # if there is type information in the header of the sig (first byte), enforce that:
         sig1_wrongtype = bytes.fromhex("27744de4516fac5c140808015664516a32fead94de89775cec7e24dbc24fe133075ac09301c4cc8e197bea4b6481661d5b8e9bf19d8b7b8a382ecdb53c2ee0750d")
         sig2_wrongtype = bytes.fromhex("24b55d7600d9e9a7e2a49155ddf3cfdb8e796c207faab833010fa41fb7828889bc47cf62348a7aaa0923c0832a589fab541e8f12eb54fb711c90e2307f0f66b194")
-        self.assertFalse(ecc.verify_usermessage_with_address(address=addr1, sig65=sig1_wrongtype, message=msg))
+        self.assertFalse(bitcoin.verify_usermessage_with_address(address=addr1, sig65=sig1_wrongtype, message=msg))
-        self.assertFalse(ecc.verify_usermessage_with_address(address=addr2, sig65=sig2_wrongtype, message=msg))
+        self.assertFalse(bitcoin.verify_usermessage_with_address(address=addr2, sig65=sig2_wrongtype, message=msg))
 
     @needs_test_with_all_aes_implementations
     def test_decrypt_message(self):
         key = WalletStorage.get_eckey_from_password('pw123')
-        self.assertEqual(b'me<(s_s)>age', key.decrypt_message(b'QklFMQMDFtgT3zWSQsa+Uie8H/WvfUjlu9UN9OJtTt3KlgKeSTi6SQfuhcg1uIz9hp3WIUOFGTLr4RNQBdjPNqzXwhkcPi2Xsbiw6UCNJncVPJ6QBg=='))
+        self.assertEqual(b'me<(s_s)>age', crypto.ecies_decrypt_message(
-        self.assertEqual(b'me<(s_s)>age', key.decrypt_message(b'QklFMQKXOXbylOQTSMGfo4MFRwivAxeEEkewWQrpdYTzjPhqjHcGBJwdIhB7DyRfRQihuXx1y0ZLLv7XxLzrILzkl/H4YUtZB4uWjuOAcmxQH4i/Og=='))
+            key, b'QklFMQMDFtgT3zWSQsa+Uie8H/WvfUjlu9UN9OJtTt3KlgKeSTi6SQfuhcg1uIz9hp3WIUOFGTLr4RNQBdjPNqzXwhkcPi2Xsbiw6UCNJncVPJ6QBg=='))
-        self.assertEqual(b'hey_there' * 100, key.decrypt_message(b'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'))
+        self.assertEqual(b'me<(s_s)>age', crypto.ecies_decrypt_message(
+            key, b'QklFMQKXOXbylOQTSMGfo4MFRwivAxeEEkewWQrpdYTzjPhqjHcGBJwdIhB7DyRfRQihuXx1y0ZLLv7XxLzrILzkl/H4YUtZB4uWjuOAcmxQH4i/Og=='))
+        self.assertEqual(b'hey_there' * 100, crypto.ecies_decrypt_message(
+            key, b'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'))
 
     @needs_test_with_all_aes_implementations
     def test_encrypt_message(self):
@@ -309,10 +312,10 @@ class Test_bitcoin(ElectrumTestCase):
             b'cannot think of anything funny'
         ]
         for plaintext in msgs:
-            ciphertext1 = key.encrypt_message(plaintext)
+            ciphertext1 = crypto.ecies_encrypt_message(key, plaintext)
-            ciphertext2 = key.encrypt_message(plaintext)
+            ciphertext2 = crypto.ecies_encrypt_message(key, plaintext)
-            self.assertEqual(plaintext, key.decrypt_message(ciphertext1))
+            self.assertEqual(plaintext, crypto.ecies_decrypt_message(key, ciphertext1))
-            self.assertEqual(plaintext, key.decrypt_message(ciphertext2))
+            self.assertEqual(plaintext, crypto.ecies_decrypt_message(key, ciphertext2))
             self.assertNotEqual(ciphertext1, ciphertext2)
 
     def test_sign_transaction(self):

tests/test_ecc.py

@@ -4,7 +4,7 @@ from ctypes import (
 )
 import io
 
-from electrum import ecc
+from electrum import ecc, bitcoin
 from electrum.ecc import ECPubkey, ECPrivkey
 from electrum.ecc_fast import _libsecp256k1
 from electrum import crypto
@@ -115,7 +115,7 @@ class TestSchnorr(ElectrumTestCase):
         )
         for tag, msg in data:
             self.assertEqual(bip340_tagged_hash__from_libsecp(tag, msg),
-                             ecc.bip340_tagged_hash(tag, msg))
+                             bitcoin.bip340_tagged_hash(tag, msg))
 
 
 class TestEcdsa(ElectrumTestCase):