Merge bitcoin#24576: contrib: testgen: remove redundant base58 implem…

…entation

65c49ac test: throw `ValueError` for invalid base58 checksum (Sebastian Falbesoner)
219d2c7 contrib: testgen: use base58 methods from test framework (Sebastian Falbesoner)
605fecf scripted-diff: rename `chars` to `b58chars` in test_framework.address (Sebastian Falbesoner)
11c63e3 contrib: testgen: import OP_* constants from test framework (Sebastian Falbesoner)
7d755bb contrib: testgen: avoid need for manually setting PYTHONPATH (Sebastian Falbesoner)

Pull request description:

  This PR removes the redundant base58 implementation [contrib/testgen/base58.py](https://github.com/bitcoin/bitcoin/blob/master/contrib/testgen/base58.py) for the test generation script `gen_key_io_test_vectors.py` and uses the one from the test framework instead. Additionally, three other cleanups/improvements are done:
  - import script operator constants `OP_*` from test framework instead of manually defining them
  - add Python path to test framework directly in the script (via `sys.path.append(...)`) instead of needing the caller to specify `PYTHONPATH=...` on the command line (the same approach is done for the signet miner and the message capture scripts)
  - rename `chars` to `b58chars` in the test_framework.address module (is more explicit and makes the diff for the base58 replacement smaller)

ACKs for top commit:
  laanwj:
    Code review ACK 65c49ac

Tree-SHA512: 92e1534cc320cd56262bf455de7231c6ec821bfcd0ed58aa5718271ecec1a89df7951bf31527a2306db6398e7f2664d2ff8508200c28163c0b164d3f5aaf8b0e

contrib/testgen/README.md

@@ -4,5 +4,5 @@ Utilities to generate test vectors for the data-driven Bitcoin tests.
 
 Usage:
 
-    PYTHONPATH=../../test/functional/test_framework ./gen_key_io_test_vectors.py valid 70 > ../../src/test/data/key_io_valid.json
-    PYTHONPATH=../../test/functional/test_framework ./gen_key_io_test_vectors.py invalid 70 > ../../src/test/data/key_io_invalid.json
+    ./gen_key_io_test_vectors.py valid 70 > ../../src/test/data/key_io_valid.json
+    ./gen_key_io_test_vectors.py invalid 70 > ../../src/test/data/key_io_invalid.json

contrib/testgen/gen_key_io_test_vectors.py

@@ -1,21 +1,25 @@
 #!/usr/bin/env python3
-# Copyright (c) 2012-2021 The Bitcoin Core developers
+# Copyright (c) 2012-2022 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
 '''
 Generate valid and invalid base58/bech32(m) address and private key test vectors.
 
 Usage:
-    PYTHONPATH=../../test/functional/test_framework ./gen_key_io_test_vectors.py valid 70 > ../../src/test/data/key_io_valid.json
-    PYTHONPATH=../../test/functional/test_framework ./gen_key_io_test_vectors.py invalid 70 > ../../src/test/data/key_io_invalid.json
+    ./gen_key_io_test_vectors.py valid 70 > ../../src/test/data/key_io_valid.json
+    ./gen_key_io_test_vectors.py invalid 70 > ../../src/test/data/key_io_invalid.json
 '''
-# 2012 Wladimir J. van der Laan
-# Released under MIT License
-import os
+
 from itertools import islice
-from base58 import b58encode_chk, b58decode_chk, b58chars
+import os
 import random
-from segwit_addr import bech32_encode, decode_segwit_address, convertbits, CHARSET, Encoding
+import sys
+
+sys.path.append(os.path.join(os.path.dirname(__file__), '../../test/functional'))
+
+from test_framework.address import base58_to_byte, byte_to_base58, b58chars  # noqa: E402
+from test_framework.script import OP_0, OP_1, OP_2, OP_3, OP_16, OP_DUP, OP_EQUAL, OP_EQUALVERIFY, OP_HASH160, OP_CHECKSIG  # noqa: E402
+from test_framework.segwit_addr import bech32_encode, decode_segwit_address, convertbits, CHARSET, Encoding  # noqa: E402
 
 # key types
 PUBKEY_ADDRESS = 0
@@ -29,16 +33,6 @@
 PRIVKEY_REGTEST = 239
 
 # script
-OP_0 = 0x00
-OP_1 = 0x51
-OP_2 = 0x52
-OP_3 = 0x53
-OP_16 = 0x60
-OP_DUP = 0x76
-OP_EQUAL = 0x87
-OP_EQUALVERIFY = 0x88
-OP_HASH160 = 0xa9
-OP_CHECKSIG = 0xac
 pubkey_prefix = (OP_DUP, OP_HASH160, 20)
 pubkey_suffix = (OP_EQUALVERIFY, OP_CHECKSIG)
 script_prefix = (OP_HASH160, 20)
@@ -114,8 +108,10 @@ def is_valid(v):
     '''Check vector v for validity'''
     if len(set(v) - set(b58chars)) > 0:
         return is_valid_bech32(v)
-    result = b58decode_chk(v)
-    if result is None:
+    try:
+        payload, version = base58_to_byte(v)
+        result = bytes([version]) + payload
+    except ValueError:  # thrown if checksum doesn't match
         return is_valid_bech32(v)
     for template in templates:
         prefix = bytearray(template[0])
@@ -139,7 +135,8 @@ def gen_valid_base58_vector(template):
     suffix = bytearray(template[2])
     dst_prefix = bytearray(template[4])
     dst_suffix = bytearray(template[5])
-    rv = b58encode_chk(prefix + payload + suffix)
+    assert len(prefix) == 1
+    rv = byte_to_base58(payload + suffix, prefix[0])
     return rv, dst_prefix + payload + dst_suffix
 
 def gen_valid_bech32_vector(template):
@@ -190,7 +187,8 @@ def gen_invalid_base58_vector(template):
     else:
         suffix = bytearray(template[2])
 
-    val = b58encode_chk(prefix + payload + suffix)
+    assert len(prefix) == 1
+    val = byte_to_base58(payload + suffix, prefix[0])
     if random.randint(0,10)<1: # line corruption
         if randbool(): # add random character to end
             val += random.choice(b58chars)
@@ -250,7 +248,6 @@ def gen_invalid_vectors():
                 yield val,
 
 if __name__ == '__main__':
-    import sys
     import json
     iters = {'valid':gen_valid_vectors, 'invalid':gen_invalid_vectors}
     try:

test/functional/test_framework/address.py

@@ -35,7 +35,7 @@ class AddressType(enum.Enum):
     legacy = 'legacy'  # P2PKH
 
 
-chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
+b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
 
 
 def create_deterministic_address_bcrt1_p2tr_op_true():
@@ -59,10 +59,10 @@ def byte_to_base58(b, version):
     b += hash256(b)[:4]       # append checksum
     value = int.from_bytes(b, 'big')
     while value > 0:
-        result = chars[value % 58] + result
+        result = b58chars[value % 58] + result
         value //= 58
     while b[0] == 0:
-        result = chars[0] + result
+        result = b58chars[0] + result
         b = b[1:]
     return result
 
@@ -76,23 +76,23 @@ def base58_to_byte(s):
     n = 0
     for c in s:
         n *= 58
-        assert c in chars
-        digit = chars.index(c)
+        assert c in b58chars
+        digit = b58chars.index(c)
         n += digit
     h = '%x' % n
     if len(h) % 2:
         h = '0' + h
     res = n.to_bytes((n.bit_length() + 7) // 8, 'big')
     pad = 0
     for c in s:
-        if c == chars[0]:
+        if c == b58chars[0]:
             pad += 1
         else:
             break
     res = b'\x00' * pad + res
 
-    # Assert if the checksum is invalid
-    assert_equal(hash256(res[:-4])[:4], res[-4:])
+    if hash256(res[:-4])[:4] != res[-4:]:
+        raise ValueError('Invalid Base58Check checksum')
 
     return res[1:-4], int(res[0])