Add tests generation material

Author: macgyver13

bip-0375/README.md

@@ -8,11 +8,25 @@ This directory contains the complete reference implementation for BIP 375: Sendi
 
 - **`reference.py`** - Minimal standalone BIP 375 validator with integrated test runner (executable)
 
+### PSBTv2 Library for Silent Payments
+
+- **`tests/psbt_sp/`** - Complete PSBT v2 package for Silent Payments
+  - Full role-based implementation (Creator, Constructor, Updater, Signer, Input Finalizer, Extractor)
+  - Serialization, crypto utilities, and BIP 352 integration
+  - Used to generate test vectors
+
 ### Dependencies (from BIP 374)
 
 - **`dleq_374.py`** - BIP 374 DLEQ proof implementation
 - **`secp256k1_374.py`** - Secp256k1 implementation
 
+## **Testing**
+
+### Test Infrastructure
+
+- **`test_vectors.json`** - Test vectors with full cryptographic material (13 invalid + 4 valid)
+- **`tests/test_generator.py`** - Deterministic test vector generator producing`test_vectors.json`
+
 ## **Usage**
 
 ### Run Reference Implementation Tests
@@ -21,4 +35,12 @@ This directory contains the complete reference implementation for BIP 375: Sendi
 python reference.py                    # Run all tests using test_vectors.json
 python reference.py -f custom.json     # Use custom test file
 python reference.py -v                 # Verbose mode with detailed errors
-```
+```
+
+### Generate Test Vectors
+
+```bash
+python tests/test_generator.py               # Creates test_vectors.json in bip-0375 root directory
+```
+
+**Note:** Demo implementations can be found in [bip375-examples](https://github.com/macgyver13/bip375-examples/)

bip-0375/tests/psbt_sp/__init__.py

@@ -0,0 +1,113 @@
+#!/usr/bin/env python3
+"""
+PSBT Silent Payment (psbt_sp) Package
+
+Clean Python package for BIP 375 - Sending Silent Payments with PSBTs
+Provides PSBT v2 implementation with silent payment extensions.
+"""
+
+# Constants
+from .constants import PSBTFieldType
+
+# Core PSBT functionality
+from .psbt import SilentPaymentPSBT, SilentPaymentAddress, ECDHShare, validate_psbt_silent_payments
+
+# Cryptographic utilities
+from .crypto import Wallet
+
+# Serialization utilities (for advanced usage)
+from .serialization import PSBTField, PSBTv2, compact_size_uint, create_witness_utxo, parse_psbt_bytes
+
+# BIP 352 cryptographic functions
+from .bip352_crypto import (
+    compute_label_tweak,
+    compute_shared_secret_tweak,
+    apply_label_to_spend_key,
+    derive_silent_payment_output_pubkey,
+    pubkey_to_p2wpkh_script
+)
+
+# PSBT utilities
+from .psbt_utils import (
+    extract_input_pubkey,
+    extract_combined_input_pubkeys,
+    check_ecdh_coverage,
+    extract_scan_keys_from_outputs
+)
+
+# File I/O
+from .psbt_io import save_psbt_to_file, load_psbt_from_file
+
+# Role-based classes
+from .roles import (
+    PSBTCreator,
+    PSBTConstructor,
+    PSBTUpdater,
+    PSBTSigner,
+    PSBTInputFinalizer,
+    PSBTExtractor
+)
+
+# Convenience re-exports of extractor methods
+extract_transaction = PSBTExtractor.extract_transaction
+save_transaction = PSBTExtractor.save_transaction
+
+__version__ = "1.0.0"
+__author__ = "BIP 375 Implementation"
+__description__ = "PSBT v2 with BIP 375 Silent Payment extensions"
+
+# Public API - what gets imported with "from psbt_sp import *"
+__all__ = [
+    # Constants
+    "PSBTFieldType",
+
+    # Core classes
+    "SilentPaymentPSBT",
+    "SilentPaymentAddress",
+    "ECDHShare",
+    "Wallet",
+
+    # Role-based classes
+    "PSBTCreator",
+    "PSBTConstructor",
+    "PSBTUpdater",
+    "PSBTSigner",
+    "PSBTInputFinalizer",
+    "PSBTExtractor",
+
+    # Serialization classes
+    "PSBTField",
+    "PSBTv2",
+
+    # BIP 352 crypto functions
+    "compute_label_tweak",
+    "compute_shared_secret_tweak",
+    "apply_label_to_spend_key",
+    "derive_silent_payment_output_pubkey",
+    "pubkey_to_p2wpkh_script",
+
+    # PSBT utility functions
+    "extract_input_pubkey",
+    "extract_combined_input_pubkeys",
+    "check_ecdh_coverage",
+    "extract_scan_keys_from_outputs",
+
+    # Transaction functions
+    "extract_transaction",
+    "save_transaction",
+
+    # File I/O functions
+    "save_psbt_to_file",
+    "load_psbt_from_file",
+
+    # Other utilities
+    "compact_size_uint",
+    "create_witness_utxo",
+    "parse_psbt_bytes",
+    "validate_psbt_silent_payments",
+
+    # Package metadata
+    "__version__",
+    "__author__",
+    "__description__"
+]

bip-0375/tests/psbt_sp/bip352_crypto.py

@@ -0,0 +1,144 @@
+#!/usr/bin/env python3
+"""
+BIP 352 Silent Payments Cryptographic Utilities
+
+Pure cryptographic functions for BIP 352 silent payments protocol.
+These functions are independent of PSBT and can be used by wallets,
+receivers, and other silent payment implementations.
+"""
+
+import hashlib
+import struct
+from secp256k1_374 import GE, G
+
+
+def compute_label_tweak(scan_privkey_bytes: bytes, label: int) -> int:
+    """
+    Compute BIP 352 label tweak for modifying spend key
+
+    Formula: hash_BIP0352/Label(ser_256(b_scan) || ser_32(m))
+
+    Args:
+        scan_privkey_bytes: Scan private key (32 bytes)
+        label: Label integer (0 for change, > 0 for other purposes)
+
+    Returns:
+        Scalar for point multiplication to modify spend key
+    """
+    # BIP 352: ser_256(b_scan) || ser_32(m)
+    label_bytes = struct.pack('<I', label)  # 4 bytes little-endian
+
+    # Tagged hash: BIP0352/Label
+    tag = b"BIP0352/Label"
+    tag_hash = hashlib.sha256(tag).digest()
+
+    # hash_BIP0352/Label(b_scan || m)
+    tagged_input = tag_hash + tag_hash + scan_privkey_bytes + label_bytes
+    tweak_hash = hashlib.sha256(tagged_input).digest()
+    tweak_scalar = int.from_bytes(tweak_hash, 'big') % GE.ORDER
+
+    return tweak_scalar
+
+
+def compute_shared_secret_tweak(ecdh_shared_secret_bytes: bytes, k: int = 0) -> int:
+    """
+    Compute BIP 352 shared secret tweak for output derivation
+
+    Formula: t_k = hash_BIP0352/SharedSecret(ecdh_shared_secret || ser_32(k))
+
+    Args:
+        ecdh_shared_secret_bytes: ECDH shared secret point (33 bytes compressed)
+        k: Output index for this scan key (default 0)
+
+    Returns:
+        Scalar tweak for deriving output public key
+    """
+    k_bytes = k.to_bytes(4, 'big')  # 4 bytes big-endian
+
+    # Tagged hash: BIP0352/SharedSecret
+    tag_data = b"BIP0352/SharedSecret"
+    tag_hash = hashlib.sha256(tag_data).digest()
+
+    tagged_input = tag_hash + tag_hash + ecdh_shared_secret_bytes + k_bytes
+    tweak_hash = hashlib.sha256(tagged_input).digest()
+    tweak_int = int.from_bytes(tweak_hash, 'big') % GE.ORDER
+
+    return tweak_int
+
+
+def apply_label_to_spend_key(spend_key_point: GE, scan_privkey_bytes: bytes, label: int) -> GE:
+    """
+    Apply BIP 352 label to spend public key
+
+    Formula: B_m = B_spend + hash_BIP0352/Label(b_scan || m) * G
+
+    Args:
+        spend_key_point: Base spend public key
+        scan_privkey_bytes: Scan private key (32 bytes)
+        label: Label integer
+
+    Returns:
+        Modified spend public key B_m
+    """
+    label_tweak = compute_label_tweak(scan_privkey_bytes, label)
+    label_tweak_point = label_tweak * G
+    return spend_key_point + label_tweak_point
+
+
+def derive_silent_payment_output_pubkey(
+    spend_key_point: GE,
+    ecdh_shared_secret_bytes: bytes,
+    k: int = 0
+) -> GE:
+    """
+    Derive final output public key for silent payment
+
+    Formula: P_k = B_m + t_k * G
+    where t_k = hash_BIP0352/SharedSecret(ecdh_shared_secret || ser_32(k))
+
+    Args:
+        spend_key_point: Spend public key (possibly label-modified B_m)
+        ecdh_shared_secret_bytes: ECDH shared secret (33 bytes compressed)
+        k: Output index for this scan key
+
+    Returns:
+        Final output public key P_k
+    """
+    tweak_int = compute_shared_secret_tweak(ecdh_shared_secret_bytes, k)
+    tweak_point = tweak_int * G
+    return spend_key_point + tweak_point
+
+
+def pubkey_to_p2wpkh_script(pubkey_point: GE) -> bytes:
+    """
+    Convert public key to P2WPKH script
+
+    Args:
+        pubkey_point: Public key point
+
+    Returns:
+        P2WPKH script: OP_0 <20-byte-pubkey-hash>
+    """
+    pubkey_bytes = pubkey_point.to_bytes_compressed()
+    pubkey_hash = hashlib.new('ripemd160', hashlib.sha256(pubkey_bytes).digest()).digest()
+    return b'\x00\x14' + pubkey_hash  # OP_0 + 20 bytes
+
+
+def pubkey_to_p2tr_script(pubkey_point: GE) -> bytes:
+    """
+    Convert public key to P2TR (Taproot) script
+
+    BIP 352 requires silent payment outputs to use P2TR (Taproot).
+    
+    Formula: OP_1 <32-byte-x-only-pubkey>
+    
+    Args:
+        pubkey_point: Public key point
+
+    Returns:
+        P2TR script: OP_1 (0x51) + 32 bytes (x-only public key)
+    """
+    # Get x-only public key (32 bytes) - BIP 340/341
+    pubkey_bytes = pubkey_point.to_bytes_compressed()
+    x_only = pubkey_bytes[1:]  # Remove first byte (02/03 parity), keep 32-byte x coordinate
+    return b'\x51\x20' + x_only  # OP_1 (0x51) + PUSH_32 (0x20) + 32 bytes

bip-0375/tests/psbt_sp/constants.py

@@ -0,0 +1,85 @@
+#!/usr/bin/env python3
+"""
+BIP 174/370/375 PSBT Field Type Constants
+
+This module defines all PSBT field type constants used across BIP 174 (PSBTv1),
+BIP 370 (PSBTv2), and BIP 375 (Silent Payments with PSBT).
+"""
+
+
+class PSBTFieldType:
+    """PSBT Field Type Constants for BIP 174/370/375"""
+
+    # =======================================================================
+    # GLOBAL FIELDS (PSBT-wide fields)
+    # =======================================================================
+
+    # Standard PSBT v2 global fields
+    PSBT_GLOBAL_UNSIGNED_TX = 0x00
+    PSBT_GLOBAL_XPUB = 0x01
+    PSBT_GLOBAL_TX_VERSION = 0x02
+    PSBT_GLOBAL_FALLBACK_LOCKTIME = 0x03
+    PSBT_GLOBAL_INPUT_COUNT = 0x04
+    PSBT_GLOBAL_OUTPUT_COUNT = 0x05
+    PSBT_GLOBAL_TX_MODIFIABLE = 0x06
+    PSBT_GLOBAL_VERSION = 0xfb
+    PSBT_GLOBAL_PROPRIETARY = 0xfc
+
+    # BIP 375 Silent Payment global fields
+    PSBT_GLOBAL_SP_ECDH_SHARE = 0x07
+    PSBT_GLOBAL_SP_DLEQ = 0x08
+
+    # =======================================================================
+    # INPUT FIELDS (Per-input fields)
+    # =======================================================================
+
+    # Standard PSBT v2 input fields
+    PSBT_IN_NON_WITNESS_UTXO = 0x00
+    PSBT_IN_WITNESS_UTXO = 0x01
+    PSBT_IN_PARTIAL_SIG = 0x02
+    PSBT_IN_SIGHASH_TYPE = 0x03
+    PSBT_IN_REDEEM_SCRIPT = 0x04
+    PSBT_IN_WITNESS_SCRIPT = 0x05
+    PSBT_IN_BIP32_DERIVATION = 0x06
+    PSBT_IN_FINAL_SCRIPTSIG = 0x07
+    PSBT_IN_FINAL_SCRIPTWITNESS = 0x08
+    PSBT_IN_POR_COMMITMENT = 0x09
+    PSBT_IN_RIPEMD160 = 0x0a
+    PSBT_IN_SHA256 = 0x0b
+    PSBT_IN_HASH160 = 0x0c
+    PSBT_IN_HASH256 = 0x0d
+    PSBT_IN_PREVIOUS_TXID = 0x0e
+    PSBT_IN_OUTPUT_INDEX = 0x0f
+    PSBT_IN_SEQUENCE = 0x10
+    PSBT_IN_REQUIRED_TIME_LOCKTIME = 0x11
+    PSBT_IN_REQUIRED_HEIGHT_LOCKTIME = 0x12
+    PSBT_IN_TAP_KEY_SIG = 0x13
+    PSBT_IN_TAP_SCRIPT_SIG = 0x14
+    PSBT_IN_TAP_LEAF_SCRIPT = 0x15
+    PSBT_IN_TAP_BIP32_DERIVATION = 0x16
+    PSBT_IN_TAP_INTERNAL_KEY = 0x17
+    PSBT_IN_TAP_MERKLE_ROOT = 0x18
+    PSBT_IN_PROPRIETARY = 0xfc
+
+    # BIP 375 Silent Payment input fields
+    PSBT_IN_SP_ECDH_SHARE = 0x1d
+    PSBT_IN_SP_DLEQ = 0x1e
+
+    # =======================================================================
+    # OUTPUT FIELDS (Per-output fields)
+    # =======================================================================
+
+    # Standard PSBT v2 output fields
+    PSBT_OUT_REDEEM_SCRIPT = 0x00
+    PSBT_OUT_WITNESS_SCRIPT = 0x01
+    PSBT_OUT_BIP32_DERIVATION = 0x02
+    PSBT_OUT_AMOUNT = 0x03
+    PSBT_OUT_SCRIPT = 0x04
+    PSBT_OUT_TAP_INTERNAL_KEY = 0x05
+    PSBT_OUT_TAP_TREE = 0x06
+    PSBT_OUT_TAP_BIP32_DERIVATION = 0x07
+    PSBT_OUT_PROPRIETARY = 0xfc
+
+    # BIP 375 Silent Payment output fields
+    PSBT_OUT_SP_V0_INFO = 0x09
+    PSBT_OUT_SP_V0_LABEL = 0x0a