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Diffstat (limited to 'test/functional/feature_taproot.py')
| -rwxr-xr-x | test/functional/feature_taproot.py | 1411 |
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diff --git a/test/functional/feature_taproot.py b/test/functional/feature_taproot.py new file mode 100755 index 0000000000..146193d018 --- /dev/null +++ b/test/functional/feature_taproot.py @@ -0,0 +1,1411 @@ +#!/usr/bin/env python3 +# Copyright (c) 2019-2020 The Bitcoin Core developers +# Distributed under the MIT software license, see the accompanying +# file COPYING or http://www.opensource.org/licenses/mit-license.php. +# Test Taproot softfork (BIPs 340-342) + +from test_framework.blocktools import ( + create_coinbase, + create_block, + add_witness_commitment, + MAX_BLOCK_SIGOPS_WEIGHT, + WITNESS_SCALE_FACTOR, +) +from test_framework.messages import ( + COutPoint, + CTransaction, + CTxIn, + CTxInWitness, + CTxOut, + ToHex, +) +from test_framework.script import ( + ANNEX_TAG, + CScript, + CScriptNum, + CScriptOp, + LEAF_VERSION_TAPSCRIPT, + LegacySignatureHash, + LOCKTIME_THRESHOLD, + MAX_SCRIPT_ELEMENT_SIZE, + OP_0, + OP_1, + OP_2, + OP_3, + OP_4, + OP_5, + OP_6, + OP_7, + OP_8, + OP_9, + OP_10, + OP_11, + OP_12, + OP_16, + OP_2DROP, + OP_2DUP, + OP_CHECKMULTISIG, + OP_CHECKMULTISIGVERIFY, + OP_CHECKSIG, + OP_CHECKSIGADD, + OP_CHECKSIGVERIFY, + OP_CODESEPARATOR, + OP_DROP, + OP_DUP, + OP_ELSE, + OP_ENDIF, + OP_EQUAL, + OP_EQUALVERIFY, + OP_HASH160, + OP_IF, + OP_NOP, + OP_NOT, + OP_NOTIF, + OP_PUSHDATA1, + OP_RETURN, + OP_SWAP, + OP_VERIFY, + SIGHASH_DEFAULT, + SIGHASH_ALL, + SIGHASH_NONE, + SIGHASH_SINGLE, + SIGHASH_ANYONECANPAY, + SegwitV0SignatureHash, + TaprootSignatureHash, + is_op_success, + taproot_construct, +) +from test_framework.test_framework import BitcoinTestFramework +from test_framework.util import assert_raises_rpc_error, assert_equal +from test_framework.key import generate_privkey, compute_xonly_pubkey, sign_schnorr, tweak_add_privkey, ECKey +from test_framework.address import ( + hash160, + sha256, +) +from collections import namedtuple +from io import BytesIO +import random + +# === Framework for building spending transactions. === +# +# The computation is represented as a "context" dict, whose entries store potentially-unevaluated expressions that +# refer to lower-level ones. By overwriting these expression, many aspects - both high and low level - of the signing +# process can be overridden. +# +# Specifically, a context object is a dict that maps names to compositions of: +# - values +# - lists of values +# - callables which, when fed the context object as argument, produce any of these +# +# The DEFAULT_CONTEXT object specifies a standard signing process, with many overridable knobs. +# +# The get(ctx, name) function can evaluate a name, and cache its result in the context. +# getter(name) can be used to construct a callable that evaluates name. For example: +# +# ctx1 = {**DEFAULT_CONTEXT, inputs=[getter("sign"), b'\x01']} +# +# creates a context where the script inputs are a signature plus the bytes 0x01. +# +# override(expr, name1=expr1, name2=expr2, ...) can be used to cause an expression to be evaluated in a selectively +# modified context. For example: +# +# ctx2 = {**DEFAULT_CONTEXT, sighash=override(default_sighash, hashtype=SIGHASH_DEFAULT)} +# +# creates a context ctx2 where the sighash is modified to use hashtype=SIGHASH_DEFAULT. This differs from +# +# ctx3 = {**DEFAULT_CONTEXT, hashtype=SIGHASH_DEFAULT} +# +# in that ctx3 will globally use hashtype=SIGHASH_DEFAULT (including in the hashtype byte appended to the signature) +# while ctx2 only uses the modified hashtype inside the sighash calculation. + +def deep_eval(ctx, expr): + """Recursively replace any callables c in expr (including inside lists) with c(ctx).""" + while callable(expr): + expr = expr(ctx) + if isinstance(expr, list): + expr = [deep_eval(ctx, x) for x in expr] + return expr + +# Data type to represent fully-evaluated expressions in a context dict (so we can avoid reevaluating them). +Final = namedtuple("Final", "value") + +def get(ctx, name): + """Evaluate name in context ctx.""" + assert name in ctx, "Missing '%s' in context" % name + expr = ctx[name] + if not isinstance(expr, Final): + # Evaluate and cache the result. + expr = Final(deep_eval(ctx, expr)) + ctx[name] = expr + return expr.value + +def getter(name): + """Return a callable that evaluates name in its passed context.""" + return lambda ctx: get(ctx, name) + +def override(expr, **kwargs): + """Return a callable that evaluates expr in a modified context.""" + return lambda ctx: deep_eval({**ctx, **kwargs}, expr) + +# === Implementations for the various default expressions in DEFAULT_CONTEXT === + +def default_hashtype(ctx): + """Default expression for "hashtype": SIGHASH_DEFAULT for taproot, SIGHASH_ALL otherwise.""" + mode = get(ctx, "mode") + if mode == "taproot": + return SIGHASH_DEFAULT + else: + return SIGHASH_ALL + +def default_tapleaf(ctx): + """Default expression for "tapleaf": looking up leaf in tap[2].""" + return get(ctx, "tap").leaves[get(ctx, "leaf")] + +def default_script_taproot(ctx): + """Default expression for "script_taproot": tapleaf.script.""" + return get(ctx, "tapleaf").script + +def default_leafversion(ctx): + """Default expression for "leafversion": tapleaf.version""" + return get(ctx, "tapleaf").version + +def default_negflag(ctx): + """Default expression for "negflag": tap.negflag.""" + return get(ctx, "tap").negflag + +def default_pubkey_inner(ctx): + """Default expression for "pubkey_inner": tap.inner_pubkey.""" + return get(ctx, "tap").inner_pubkey + +def default_merklebranch(ctx): + """Default expression for "merklebranch": tapleaf.merklebranch.""" + return get(ctx, "tapleaf").merklebranch + +def default_controlblock(ctx): + """Default expression for "controlblock": combine leafversion, negflag, pubkey_inner, merklebranch.""" + return bytes([get(ctx, "leafversion") + get(ctx, "negflag")]) + get(ctx, "pubkey_inner") + get(ctx, "merklebranch") + +def default_sighash(ctx): + """Default expression for "sighash": depending on mode, compute BIP341, BIP143, or legacy sighash.""" + tx = get(ctx, "tx") + idx = get(ctx, "idx") + hashtype = get(ctx, "hashtype_actual") + mode = get(ctx, "mode") + if mode == "taproot": + # BIP341 signature hash + utxos = get(ctx, "utxos") + annex = get(ctx, "annex") + if get(ctx, "leaf") is not None: + codeseppos = get(ctx, "codeseppos") + leaf_ver = get(ctx, "leafversion") + script = get(ctx, "script_taproot") + return TaprootSignatureHash(tx, utxos, hashtype, idx, scriptpath=True, script=script, leaf_ver=leaf_ver, codeseparator_pos=codeseppos, annex=annex) + else: + return TaprootSignatureHash(tx, utxos, hashtype, idx, scriptpath=False, annex=annex) + elif mode == "witv0": + # BIP143 signature hash + scriptcode = get(ctx, "scriptcode") + utxos = get(ctx, "utxos") + return SegwitV0SignatureHash(scriptcode, tx, idx, hashtype, utxos[idx].nValue) + else: + # Pre-segwit signature hash + scriptcode = get(ctx, "scriptcode") + return LegacySignatureHash(scriptcode, tx, idx, hashtype)[0] + +def default_tweak(ctx): + """Default expression for "tweak": None if a leaf is specified, tap[0] otherwise.""" + if get(ctx, "leaf") is None: + return get(ctx, "tap").tweak + return None + +def default_key_tweaked(ctx): + """Default expression for "key_tweaked": key if tweak is None, tweaked with it otherwise.""" + key = get(ctx, "key") + tweak = get(ctx, "tweak") + if tweak is None: + return key + else: + return tweak_add_privkey(key, tweak) + +def default_signature(ctx): + """Default expression for "signature": BIP340 signature or ECDSA signature depending on mode.""" + sighash = get(ctx, "sighash") + if get(ctx, "mode") == "taproot": + key = get(ctx, "key_tweaked") + flip_r = get(ctx, "flag_flip_r") + flip_p = get(ctx, "flag_flip_p") + return sign_schnorr(key, sighash, flip_r=flip_r, flip_p=flip_p) + else: + key = get(ctx, "key") + return key.sign_ecdsa(sighash) + +def default_hashtype_actual(ctx): + """Default expression for "hashtype_actual": hashtype, unless mismatching SIGHASH_SINGLE in taproot.""" + hashtype = get(ctx, "hashtype") + mode = get(ctx, "mode") + if mode != "taproot": + return hashtype + idx = get(ctx, "idx") + tx = get(ctx, "tx") + if hashtype & 3 == SIGHASH_SINGLE and idx >= len(tx.vout): + return (hashtype & ~3) | SIGHASH_NONE + return hashtype + +def default_bytes_hashtype(ctx): + """Default expression for "bytes_hashtype": bytes([hashtype_actual]) if not 0, b"" otherwise.""" + return bytes([x for x in [get(ctx, "hashtype_actual")] if x != 0]) + +def default_sign(ctx): + """Default expression for "sign": concatenation of signature and bytes_hashtype.""" + return get(ctx, "signature") + get(ctx, "bytes_hashtype") + +def default_inputs_keypath(ctx): + """Default expression for "inputs_keypath": a signature.""" + return [get(ctx, "sign")] + +def default_witness_taproot(ctx): + """Default expression for "witness_taproot", consisting of inputs, script, control block, and annex as needed.""" + annex = get(ctx, "annex") + suffix_annex = [] + if annex is not None: + suffix_annex = [annex] + if get(ctx, "leaf") is None: + return get(ctx, "inputs_keypath") + suffix_annex + else: + return get(ctx, "inputs") + [bytes(get(ctx, "script_taproot")), get(ctx, "controlblock")] + suffix_annex + +def default_witness_witv0(ctx): + """Default expression for "witness_witv0", consisting of inputs and witness script, as needed.""" + script = get(ctx, "script_witv0") + inputs = get(ctx, "inputs") + if script is None: + return inputs + else: + return inputs + [script] + +def default_witness(ctx): + """Default expression for "witness", delegating to "witness_taproot" or "witness_witv0" as needed.""" + mode = get(ctx, "mode") + if mode == "taproot": + return get(ctx, "witness_taproot") + elif mode == "witv0": + return get(ctx, "witness_witv0") + else: + return [] + +def default_scriptsig(ctx): + """Default expression for "scriptsig", consisting of inputs and redeemscript, as needed.""" + scriptsig = [] + mode = get(ctx, "mode") + if mode == "legacy": + scriptsig = get(ctx, "inputs") + redeemscript = get(ctx, "script_p2sh") + if redeemscript is not None: + scriptsig += [bytes(redeemscript)] + return scriptsig + +# The default context object. +DEFAULT_CONTEXT = { + # == The main expressions to evaluate. Only override these for unusual or invalid spends. == + # The overall witness stack, as a list of bytes objects. + "witness": default_witness, + # The overall scriptsig, as a list of CScript objects (to be concatenated) and bytes objects (to be pushed) + "scriptsig": default_scriptsig, + + # == Expressions you'll generally only override for intentionally invalid spends. == + # The witness stack for spending a taproot output. + "witness_taproot": default_witness_taproot, + # The witness stack for spending a P2WPKH/P2WSH output. + "witness_witv0": default_witness_witv0, + # The script inputs for a taproot key path spend. + "inputs_keypath": default_inputs_keypath, + # The actual hashtype to use (usually equal to hashtype, but in taproot SIGHASH_SINGLE is not always allowed). + "hashtype_actual": default_hashtype_actual, + # The bytes object for a full signature (including hashtype byte, if needed). + "bytes_hashtype": default_bytes_hashtype, + # A full script signature (bytes including hashtype, if needed) + "sign": default_sign, + # An ECDSA or Schnorr signature (excluding hashtype byte). + "signature": default_signature, + # The 32-byte tweaked key (equal to key for script path spends, or key+tweak for key path spends). + "key_tweaked": default_key_tweaked, + # The tweak to use (None for script path spends, the actual tweak for key path spends). + "tweak": default_tweak, + # The sighash value (32 bytes) + "sighash": default_sighash, + # The information about the chosen script path spend (TaprootLeafInfo object). + "tapleaf": default_tapleaf, + # The script to push, and include in the sighash, for a taproot script path spend. + "script_taproot": default_script_taproot, + # The inner pubkey for a taproot script path spend (32 bytes). + "pubkey_inner": default_pubkey_inner, + # The negation flag of the inner pubkey for a taproot script path spend. + "negflag": default_negflag, + # The leaf version to include in the sighash (this does not affect the one in the control block). + "leafversion": default_leafversion, + # The Merkle path to include in the control block for a script path spend. + "merklebranch": default_merklebranch, + # The control block to push for a taproot script path spend. + "controlblock": default_controlblock, + # Whether to produce signatures with invalid P sign (Schnorr signatures only). + "flag_flip_p": False, + # Whether to produce signatures with invalid R sign (Schnorr signatures only). + "flag_flip_r": False, + + # == Parameters that can be changed without invalidating, but do have a default: == + # The hashtype (as an integer). + "hashtype": default_hashtype, + # The annex (only when mode=="taproot"). + "annex": None, + # The codeseparator position (only when mode=="taproot"). + "codeseppos": -1, + # The redeemscript to add to the scriptSig (if P2SH; None implies not P2SH). + "script_p2sh": None, + # The script to add to the witness in (if P2WSH; None implies P2WPKH) + "script_witv0": None, + # The leaf to use in taproot spends (if script path spend; None implies key path spend). + "leaf": None, + # The input arguments to provide to the executed script + "inputs": [], + + # == Parameters to be set before evaluation: == + # - mode: what spending style to use ("taproot", "witv0", or "legacy"). + # - key: the (untweaked) private key to sign with (ECKey object for ECDSA, 32 bytes for Schnorr). + # - tap: the TaprootInfo object (see taproot_construct; needed in mode=="taproot"). + # - tx: the transaction to sign. + # - utxos: the UTXOs being spent (needed in mode=="witv0" and mode=="taproot"). + # - idx: the input position being signed. + # - scriptcode: the scriptcode to include in legacy and witv0 sighashes. +} + +def flatten(lst): + ret = [] + for elem in lst: + if isinstance(elem, list): + ret += flatten(elem) + else: + ret.append(elem) + return ret + +def spend(tx, idx, utxos, **kwargs): + """Sign transaction input idx of tx, provided utxos is the list of outputs being spent. + + Additional arguments may be provided that override any aspect of the signing process. + See DEFAULT_CONTEXT above for what can be overridden, and what must be provided. + """ + + ctx = {**DEFAULT_CONTEXT, "tx":tx, "idx":idx, "utxos":utxos, **kwargs} + + def to_script(elem): + """If fed a CScript, return it; if fed bytes, return a CScript that pushes it.""" + if isinstance(elem, CScript): + return elem + else: + return CScript([elem]) + + scriptsig_list = flatten(get(ctx, "scriptsig")) + scriptsig = CScript(b"".join(bytes(to_script(elem)) for elem in scriptsig_list)) + witness_stack = flatten(get(ctx, "witness")) + return (scriptsig, witness_stack) + + +# === Spender objects === +# +# Each spender is a tuple of: +# - A scriptPubKey which is to be spent from (CScript) +# - A comment describing the test (string) +# - Whether the spending (on itself) is expected to be standard (bool) +# - A tx-signing lambda returning (scriptsig, witness_stack), taking as inputs: +# - A transaction to sign (CTransaction) +# - An input position (int) +# - The spent UTXOs by this transaction (list of CTxOut) +# - Whether to produce a valid spend (bool) +# - A string with an expected error message for failure case if known +# - The (pre-taproot) sigops weight consumed by a successful spend +# - Whether this spend cannot fail +# - Whether this test demands being placed in a txin with no corresponding txout (for testing SIGHASH_SINGLE behavior) + +Spender = namedtuple("Spender", "script,comment,is_standard,sat_function,err_msg,sigops_weight,no_fail,need_vin_vout_mismatch") + +def make_spender(comment, *, tap=None, witv0=False, script=None, pkh=None, p2sh=False, spk_mutate_pre_p2sh=None, failure=None, standard=True, err_msg=None, sigops_weight=0, need_vin_vout_mismatch=False, **kwargs): + """Helper for constructing Spender objects using the context signing framework. + + * tap: a TaprootInfo object (see taproot_construct), for Taproot spends (cannot be combined with pkh, witv0, or script) + * witv0: boolean indicating the use of witness v0 spending (needs one of script or pkh) + * script: the actual script executed (for bare/P2WSH/P2SH spending) + * pkh: the public key for P2PKH or P2WPKH spending + * p2sh: whether the output is P2SH wrapper (this is supported even for Taproot, where it makes the output unencumbered) + * spk_mutate_pre_psh: a callable to be applied to the script (before potentially P2SH-wrapping it) + * failure: a dict of entries to override in the context when intentionally failing to spend (if None, no_fail will be set) + * standard: whether the (valid version of) spending is expected to be standard + * err_msg: a string with an expected error message for failure (or None, if not cared about) + * sigops_weight: the pre-taproot sigops weight consumed by a successful spend + """ + + conf = dict() + + # Compute scriptPubKey and set useful defaults based on the inputs. + if witv0: + assert tap is None + conf["mode"] = "witv0" + if pkh is not None: + # P2WPKH + assert script is None + pubkeyhash = hash160(pkh) + spk = CScript([OP_0, pubkeyhash]) + conf["scriptcode"] = CScript([OP_DUP, OP_HASH160, pubkeyhash, OP_EQUALVERIFY, OP_CHECKSIG]) + conf["script_witv0"] = None + conf["inputs"] = [getter("sign"), pkh] + elif script is not None: + # P2WSH + spk = CScript([OP_0, sha256(script)]) + conf["scriptcode"] = script + conf["script_witv0"] = script + else: + assert False + elif tap is None: + conf["mode"] = "legacy" + if pkh is not None: + # P2PKH + assert script is None + pubkeyhash = hash160(pkh) + spk = CScript([OP_DUP, OP_HASH160, pubkeyhash, OP_EQUALVERIFY, OP_CHECKSIG]) + conf["scriptcode"] = spk + conf["inputs"] = [getter("sign"), pkh] + elif script is not None: + # bare + spk = script + conf["scriptcode"] = script + else: + assert False + else: + assert script is None + conf["mode"] = "taproot" + conf["tap"] = tap + spk = tap.scriptPubKey + + if spk_mutate_pre_p2sh is not None: + spk = spk_mutate_pre_p2sh(spk) + + if p2sh: + # P2SH wrapper can be combined with anything else + conf["script_p2sh"] = spk + spk = CScript([OP_HASH160, hash160(spk), OP_EQUAL]) + + conf = {**conf, **kwargs} + + def sat_fn(tx, idx, utxos, valid): + if valid: + return spend(tx, idx, utxos, **conf) + else: + assert failure is not None + return spend(tx, idx, utxos, **{**conf, **failure}) + + return Spender(script=spk, comment=comment, is_standard=standard, sat_function=sat_fn, err_msg=err_msg, sigops_weight=sigops_weight, no_fail=failure is None, need_vin_vout_mismatch=need_vin_vout_mismatch) + +def add_spender(spenders, *args, **kwargs): + """Make a spender using make_spender, and add it to spenders.""" + spenders.append(make_spender(*args, **kwargs)) + +# === Helpers for the test === + +def random_checksig_style(pubkey): + """Creates a random CHECKSIG* tapscript that would succeed with only the valid signature on witness stack.""" + return bytes(CScript([pubkey, OP_CHECKSIG])) + opcode = random.choice([OP_CHECKSIG, OP_CHECKSIGVERIFY, OP_CHECKSIGADD]) + if (opcode == OP_CHECKSIGVERIFY): + ret = CScript([pubkey, opcode, OP_1]) + elif (opcode == OP_CHECKSIGADD): + num = random.choice([0, 0x7fffffff, -0x7fffffff]) + ret = CScript([num, pubkey, opcode, num + 1, OP_EQUAL]) + else: + ret = CScript([pubkey, opcode]) + return bytes(ret) + +def random_bytes(n): + """Return a random bytes object of length n.""" + return bytes(random.getrandbits(8) for i in range(n)) + +def bitflipper(expr): + """Return a callable that evaluates expr and returns it with a random bitflip.""" + def fn(ctx): + sub = deep_eval(ctx, expr) + assert isinstance(sub, bytes) + return (int.from_bytes(sub, 'little') ^ (1 << random.randrange(len(sub) * 8))).to_bytes(len(sub), 'little') + return fn + +def zero_appender(expr): + """Return a callable that evaluates expr and returns it with a zero added.""" + return lambda ctx: deep_eval(ctx, expr) + b"\x00" + +def byte_popper(expr): + """Return a callable that evaluates expr and returns it with its last byte removed.""" + return lambda ctx: deep_eval(ctx, expr)[:-1] + +# Expected error strings + +ERR_SIG_SIZE = {"err_msg": "Invalid Schnorr signature size"} +ERR_SIG_HASHTYPE = {"err_msg": "Invalid Schnorr signature hash type"} +ERR_SIG_SCHNORR = {"err_msg": "Invalid Schnorr signature"} +ERR_OP_RETURN = {"err_msg": "OP_RETURN was encountered"} +ERR_CONTROLBLOCK_SIZE = {"err_msg": "Invalid Taproot control block size"} +ERR_WITNESS_PROGRAM_MISMATCH = {"err_msg": "Witness program hash mismatch"} +ERR_PUSH_LIMIT = {"err_msg": "Push value size limit exceeded"} +ERR_DISABLED_OPCODE = {"err_msg": "Attempted to use a disabled opcode"} +ERR_TAPSCRIPT_CHECKMULTISIG = {"err_msg": "OP_CHECKMULTISIG(VERIFY) is not available in tapscript"} +ERR_MINIMALIF = {"err_msg": "OP_IF/NOTIF argument must be minimal in tapscript"} +ERR_UNKNOWN_PUBKEY = {"err_msg": "Public key is neither compressed or uncompressed"} +ERR_STACK_SIZE = {"err_msg": "Stack size limit exceeded"} +ERR_CLEANSTACK = {"err_msg": "Stack size must be exactly one after execution"} +ERR_STACK_EMPTY = {"err_msg": "Operation not valid with the current stack size"} +ERR_SIGOPS_RATIO = {"err_msg": "Too much signature validation relative to witness weight"} +ERR_UNDECODABLE = {"err_msg": "Opcode missing or not understood"} +ERR_NO_SUCCESS = {"err_msg": "Script evaluated without error but finished with a false/empty top stack element"} +ERR_EMPTY_WITNESS = {"err_msg": "Witness program was passed an empty witness"} +ERR_CHECKSIGVERIFY = {"err_msg": "Script failed an OP_CHECKSIGVERIFY operation"} + +VALID_SIGHASHES_ECDSA = [ + SIGHASH_ALL, + SIGHASH_NONE, + SIGHASH_SINGLE, + SIGHASH_ANYONECANPAY + SIGHASH_ALL, + SIGHASH_ANYONECANPAY + SIGHASH_NONE, + SIGHASH_ANYONECANPAY + SIGHASH_SINGLE +] + +VALID_SIGHASHES_TAPROOT = [SIGHASH_DEFAULT] + VALID_SIGHASHES_ECDSA + +VALID_SIGHASHES_TAPROOT_SINGLE = [ + SIGHASH_SINGLE, + SIGHASH_ANYONECANPAY + SIGHASH_SINGLE +] + +VALID_SIGHASHES_TAPROOT_NO_SINGLE = [h for h in VALID_SIGHASHES_TAPROOT if h not in VALID_SIGHASHES_TAPROOT_SINGLE] + +SIGHASH_BITFLIP = {"failure": {"sighash": bitflipper(default_sighash)}} +SIG_POP_BYTE = {"failure": {"sign": byte_popper(default_sign)}} +SINGLE_SIG = {"inputs": [getter("sign")]} +SIG_ADD_ZERO = {"failure": {"sign": zero_appender(default_sign)}} + +DUST_LIMIT = 600 +MIN_FEE = 50000 + +# === Actual test cases === + + +def spenders_taproot_active(): + """Return a list of Spenders for testing post-Taproot activation behavior.""" + + secs = [generate_privkey() for _ in range(8)] + pubs = [compute_xonly_pubkey(sec)[0] for sec in secs] + + spenders = [] + + # == Tests for BIP340 signature validation. == + # These are primarily tested through the test vectors implemented in libsecp256k1, and in src/tests/key_tests.cpp. + # Some things are tested programmatically as well here. + + tap = taproot_construct(pubs[0]) + # Test with key with bit flipped. + add_spender(spenders, "sig/key", tap=tap, key=secs[0], failure={"key_tweaked": bitflipper(default_key_tweaked)}, **ERR_SIG_SCHNORR) + # Test with sighash with bit flipped. + add_spender(spenders, "sig/sighash", tap=tap, key=secs[0], failure={"sighash": bitflipper(default_sighash)}, **ERR_SIG_SCHNORR) + # Test with invalid R sign. + add_spender(spenders, "sig/flip_r", tap=tap, key=secs[0], failure={"flag_flip_r": True}, **ERR_SIG_SCHNORR) + # Test with invalid P sign. + add_spender(spenders, "sig/flip_p", tap=tap, key=secs[0], failure={"flag_flip_p": True}, **ERR_SIG_SCHNORR) + # Test with signature with bit flipped. + add_spender(spenders, "sig/bitflip", tap=tap, key=secs[0], failure={"signature": bitflipper(default_signature)}, **ERR_SIG_SCHNORR) + + # == Tests for signature hashing == + + # Run all tests once with no annex, and once with a valid random annex. + for annex in [None, lambda _: bytes([ANNEX_TAG]) + random_bytes(random.randrange(0, 250))]: + # Non-empty annex is non-standard + no_annex = annex is None + + # Sighash mutation tests (test all sighash combinations) + for hashtype in VALID_SIGHASHES_TAPROOT: + common = {"annex": annex, "hashtype": hashtype, "standard": no_annex} + + # Pure pubkey + tap = taproot_construct(pubs[0]) + add_spender(spenders, "sighash/purepk", tap=tap, key=secs[0], **common, **SIGHASH_BITFLIP, **ERR_SIG_SCHNORR) + + # Pubkey/P2PK script combination + scripts = [("s0", CScript(random_checksig_style(pubs[1])))] + tap = taproot_construct(pubs[0], scripts) + add_spender(spenders, "sighash/keypath_hashtype_%x" % hashtype, tap=tap, key=secs[0], **common, **SIGHASH_BITFLIP, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/scriptpath_hashtype_%x" % hashtype, tap=tap, leaf="s0", key=secs[1], **common, **SINGLE_SIG, **SIGHASH_BITFLIP, **ERR_SIG_SCHNORR) + + # Test SIGHASH_SINGLE behavior in combination with mismatching outputs + if hashtype in VALID_SIGHASHES_TAPROOT_SINGLE: + add_spender(spenders, "sighash/keypath_hashtype_mis_%x" % hashtype, tap=tap, key=secs[0], annex=annex, standard=no_annex, hashtype_actual=random.choice(VALID_SIGHASHES_TAPROOT_NO_SINGLE), failure={"hashtype_actual": hashtype}, **ERR_SIG_HASHTYPE, need_vin_vout_mismatch=True) + add_spender(spenders, "sighash/scriptpath_hashtype_mis_%x" % hashtype, tap=tap, leaf="s0", key=secs[1], annex=annex, standard=no_annex, hashtype_actual=random.choice(VALID_SIGHASHES_TAPROOT_NO_SINGLE), **SINGLE_SIG, failure={"hashtype_actual": hashtype}, **ERR_SIG_HASHTYPE, need_vin_vout_mismatch=True) + + # Test OP_CODESEPARATOR impact on sighashing. + hashtype = lambda _: random.choice(VALID_SIGHASHES_TAPROOT) + common = {"annex": annex, "hashtype": hashtype, "standard": no_annex} + scripts = [ + ("pk_codesep", CScript(random_checksig_style(pubs[1]) + bytes([OP_CODESEPARATOR]))), # codesep after checksig + ("codesep_pk", CScript(bytes([OP_CODESEPARATOR]) + random_checksig_style(pubs[1]))), # codesep before checksig + ("branched_codesep", CScript([random_bytes(random.randrange(511)), OP_DROP, OP_IF, OP_CODESEPARATOR, pubs[0], OP_ELSE, OP_CODESEPARATOR, pubs[1], OP_ENDIF, OP_CHECKSIG])), # branch dependent codesep + ] + random.shuffle(scripts) + tap = taproot_construct(pubs[0], scripts) + add_spender(spenders, "sighash/pk_codesep", tap=tap, leaf="pk_codesep", key=secs[1], **common, **SINGLE_SIG, **SIGHASH_BITFLIP, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/codesep_pk", tap=tap, leaf="codesep_pk", key=secs[1], codeseppos=0, **common, **SINGLE_SIG, **SIGHASH_BITFLIP, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/branched_codesep/left", tap=tap, leaf="branched_codesep", key=secs[0], codeseppos=3, **common, inputs=[getter("sign"), b'\x01'], **SIGHASH_BITFLIP, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/branched_codesep/right", tap=tap, leaf="branched_codesep", key=secs[1], codeseppos=6, **common, inputs=[getter("sign"), b''], **SIGHASH_BITFLIP, **ERR_SIG_SCHNORR) + + # Reusing the scripts above, test that various features affect the sighash. + add_spender(spenders, "sighash/annex", tap=tap, leaf="pk_codesep", key=secs[1], hashtype=hashtype, standard=False, **SINGLE_SIG, annex=bytes([ANNEX_TAG]), failure={"sighash": override(default_sighash, annex=None)}, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/script", tap=tap, leaf="pk_codesep", key=secs[1], **common, **SINGLE_SIG, failure={"sighash": override(default_sighash, script_taproot=tap.leaves["codesep_pk"].script)}, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/leafver", tap=tap, leaf="pk_codesep", key=secs[1], **common, **SINGLE_SIG, failure={"sighash": override(default_sighash, leafversion=random.choice([x & 0xFE for x in range(0x100) if x & 0xFE != 0xC0]))}, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/scriptpath", tap=tap, leaf="pk_codesep", key=secs[1], **common, **SINGLE_SIG, failure={"sighash": override(default_sighash, leaf=None)}, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/keypath", tap=tap, key=secs[0], **common, failure={"sighash": override(default_sighash, leaf="pk_codesep")}, **ERR_SIG_SCHNORR) + + # Test that invalid hashtypes don't work, both in key path and script path spends + hashtype = lambda _: random.choice(VALID_SIGHASHES_TAPROOT) + for invalid_hashtype in [x for x in range(0x100) if x not in VALID_SIGHASHES_TAPROOT]: + add_spender(spenders, "sighash/keypath_unk_hashtype_%x" % invalid_hashtype, tap=tap, key=secs[0], hashtype=hashtype, failure={"hashtype": invalid_hashtype}, **ERR_SIG_HASHTYPE) + add_spender(spenders, "sighash/scriptpath_unk_hashtype_%x" % invalid_hashtype, tap=tap, leaf="pk_codesep", key=secs[1], **SINGLE_SIG, hashtype=hashtype, failure={"hashtype": invalid_hashtype}, **ERR_SIG_HASHTYPE) + + # Test that hashtype 0 cannot have a hashtype byte, and 1 must have one. + add_spender(spenders, "sighash/hashtype0_byte_keypath", tap=tap, key=secs[0], hashtype=SIGHASH_DEFAULT, failure={"bytes_hashtype": bytes([SIGHASH_DEFAULT])}, **ERR_SIG_HASHTYPE) + add_spender(spenders, "sighash/hashtype0_byte_scriptpath", tap=tap, leaf="pk_codesep", key=secs[1], **SINGLE_SIG, hashtype=SIGHASH_DEFAULT, failure={"bytes_hashtype": bytes([SIGHASH_DEFAULT])}, **ERR_SIG_HASHTYPE) + add_spender(spenders, "sighash/hashtype1_byte_keypath", tap=tap, key=secs[0], hashtype=SIGHASH_ALL, failure={"bytes_hashtype": b''}, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/hashtype1_byte_scriptpath", tap=tap, leaf="pk_codesep", key=secs[1], **SINGLE_SIG, hashtype=SIGHASH_ALL, failure={"bytes_hashtype": b''}, **ERR_SIG_SCHNORR) + # Test that hashtype 0 and hashtype 1 cannot be transmuted into each other. + add_spender(spenders, "sighash/hashtype0to1_keypath", tap=tap, key=secs[0], hashtype=SIGHASH_DEFAULT, failure={"bytes_hashtype": bytes([SIGHASH_ALL])}, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/hashtype0to1_scriptpath", tap=tap, leaf="pk_codesep", key=secs[1], **SINGLE_SIG, hashtype=SIGHASH_DEFAULT, failure={"bytes_hashtype": bytes([SIGHASH_ALL])}, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/hashtype1to0_keypath", tap=tap, key=secs[0], hashtype=SIGHASH_ALL, failure={"bytes_hashtype": b''}, **ERR_SIG_SCHNORR) + add_spender(spenders, "sighash/hashtype1to0_scriptpath", tap=tap, leaf="pk_codesep", key=secs[1], **SINGLE_SIG, hashtype=SIGHASH_ALL, failure={"bytes_hashtype": b''}, **ERR_SIG_SCHNORR) + + # Test aspects of signatures with unusual lengths + for hashtype in [SIGHASH_DEFAULT, random.choice(VALID_SIGHASHES_TAPROOT)]: + scripts = [ + ("csv", CScript([pubs[2], OP_CHECKSIGVERIFY, OP_1])), + ("cs_pos", CScript([pubs[2], OP_CHECKSIG])), + ("csa_pos", CScript([OP_0, pubs[2], OP_CHECKSIGADD, OP_1, OP_EQUAL])), + ("cs_neg", CScript([pubs[2], OP_CHECKSIG, OP_NOT])), + ("csa_neg", CScript([OP_2, pubs[2], OP_CHECKSIGADD, OP_2, OP_EQUAL])) + ] + random.shuffle(scripts) + tap = taproot_construct(pubs[3], scripts) + # Empty signatures + add_spender(spenders, "siglen/empty_keypath", tap=tap, key=secs[3], hashtype=hashtype, failure={"sign": b""}, **ERR_SIG_SIZE) + add_spender(spenders, "siglen/empty_csv", tap=tap, key=secs[2], leaf="csv", hashtype=hashtype, **SINGLE_SIG, failure={"sign": b""}, **ERR_CHECKSIGVERIFY) + add_spender(spenders, "siglen/empty_cs", tap=tap, key=secs[2], leaf="cs_pos", hashtype=hashtype, **SINGLE_SIG, failure={"sign": b""}, **ERR_NO_SUCCESS) + add_spender(spenders, "siglen/empty_csa", tap=tap, key=secs[2], leaf="csa_pos", hashtype=hashtype, **SINGLE_SIG, failure={"sign": b""}, **ERR_NO_SUCCESS) + add_spender(spenders, "siglen/empty_cs_neg", tap=tap, key=secs[2], leaf="cs_neg", hashtype=hashtype, **SINGLE_SIG, sign=b"", failure={"sign": lambda _: random_bytes(random.randrange(1, 63))}, **ERR_SIG_SIZE) + add_spender(spenders, "siglen/empty_csa_neg", tap=tap, key=secs[2], leaf="csa_neg", hashtype=hashtype, **SINGLE_SIG, sign=b"", failure={"sign": lambda _: random_bytes(random.randrange(66, 100))}, **ERR_SIG_SIZE) + # Appending a zero byte to signatures invalidates them + add_spender(spenders, "siglen/padzero_keypath", tap=tap, key=secs[3], hashtype=hashtype, **SIG_ADD_ZERO, **(ERR_SIG_HASHTYPE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SIZE)) + add_spender(spenders, "siglen/padzero_csv", tap=tap, key=secs[2], leaf="csv", hashtype=hashtype, **SINGLE_SIG, **SIG_ADD_ZERO, **(ERR_SIG_HASHTYPE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SIZE)) + add_spender(spenders, "siglen/padzero_cs", tap=tap, key=secs[2], leaf="cs_pos", hashtype=hashtype, **SINGLE_SIG, **SIG_ADD_ZERO, **(ERR_SIG_HASHTYPE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SIZE)) + add_spender(spenders, "siglen/padzero_csa", tap=tap, key=secs[2], leaf="csa_pos", hashtype=hashtype, **SINGLE_SIG, **SIG_ADD_ZERO, **(ERR_SIG_HASHTYPE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SIZE)) + add_spender(spenders, "siglen/padzero_cs_neg", tap=tap, key=secs[2], leaf="cs_neg", hashtype=hashtype, **SINGLE_SIG, sign=b"", **SIG_ADD_ZERO, **(ERR_SIG_HASHTYPE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SIZE)) + add_spender(spenders, "siglen/padzero_csa_neg", tap=tap, key=secs[2], leaf="csa_neg", hashtype=hashtype, **SINGLE_SIG, sign=b"", **SIG_ADD_ZERO, **(ERR_SIG_HASHTYPE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SIZE)) + # Removing the last byte from signatures invalidates them + add_spender(spenders, "siglen/popbyte_keypath", tap=tap, key=secs[3], hashtype=hashtype, **SIG_POP_BYTE, **(ERR_SIG_SIZE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SCHNORR)) + add_spender(spenders, "siglen/popbyte_csv", tap=tap, key=secs[2], leaf="csv", hashtype=hashtype, **SINGLE_SIG, **SIG_POP_BYTE, **(ERR_SIG_SIZE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SCHNORR)) + add_spender(spenders, "siglen/popbyte_cs", tap=tap, key=secs[2], leaf="cs_pos", hashtype=hashtype, **SINGLE_SIG, **SIG_POP_BYTE, **(ERR_SIG_SIZE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SCHNORR)) + add_spender(spenders, "siglen/popbyte_csa", tap=tap, key=secs[2], leaf="csa_pos", hashtype=hashtype, **SINGLE_SIG, **SIG_POP_BYTE, **(ERR_SIG_SIZE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SCHNORR)) + add_spender(spenders, "siglen/popbyte_cs_neg", tap=tap, key=secs[2], leaf="cs_neg", hashtype=hashtype, **SINGLE_SIG, sign=b"", **SIG_POP_BYTE, **(ERR_SIG_SIZE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SCHNORR)) + add_spender(spenders, "siglen/popbyte_csa_neg", tap=tap, key=secs[2], leaf="csa_neg", hashtype=hashtype, **SINGLE_SIG, sign=b"", **SIG_POP_BYTE, **(ERR_SIG_SIZE if hashtype == SIGHASH_DEFAULT else ERR_SIG_SCHNORR)) + # Verify that an invalid signature is not allowed, not even when the CHECKSIG* is expected to fail. + add_spender(spenders, "siglen/invalid_cs_neg", tap=tap, key=secs[2], leaf="cs_neg", hashtype=hashtype, **SINGLE_SIG, sign=b"", failure={"sign": default_sign, "sighash": bitflipper(default_sighash)}, **ERR_SIG_SCHNORR) + add_spender(spenders, "siglen/invalid_csa_neg", tap=tap, key=secs[2], leaf="csa_neg", hashtype=hashtype, **SINGLE_SIG, sign=b"", failure={"sign": default_sign, "sighash": bitflipper(default_sighash)}, **ERR_SIG_SCHNORR) + + # == Test that BIP341 spending only applies to witness version 1, program length 32, no P2SH == + + for p2sh in [False, True]: + for witver in range(1, 17): + for witlen in [20, 31, 32, 33]: + def mutate(spk): + prog = spk[2:] + assert len(prog) == 32 + if witlen < 32: + prog = prog[0:witlen] + elif witlen > 32: + prog += bytes([0 for _ in range(witlen - 32)]) + return CScript([CScriptOp.encode_op_n(witver), prog]) + scripts = [("s0", CScript([pubs[0], OP_CHECKSIG])), ("dummy", CScript([OP_RETURN]))] + tap = taproot_construct(pubs[1], scripts) + if not p2sh and witver == 1 and witlen == 32: + add_spender(spenders, "applic/keypath", p2sh=p2sh, spk_mutate_pre_p2sh=mutate, tap=tap, key=secs[1], **SIGHASH_BITFLIP, **ERR_SIG_SCHNORR) + add_spender(spenders, "applic/scriptpath", p2sh=p2sh, leaf="s0", spk_mutate_pre_p2sh=mutate, tap=tap, key=secs[0], **SINGLE_SIG, failure={"leaf": "dummy"}, **ERR_OP_RETURN) + else: + add_spender(spenders, "applic/keypath", p2sh=p2sh, spk_mutate_pre_p2sh=mutate, tap=tap, key=secs[1], standard=False) + add_spender(spenders, "applic/scriptpath", p2sh=p2sh, leaf="s0", spk_mutate_pre_p2sh=mutate, tap=tap, key=secs[0], **SINGLE_SIG, standard=False) + + # == Test various aspects of BIP341 spending paths == + + # A set of functions that compute the hashing partner in a Merkle tree, designed to exercise + # edge cases. This relies on the taproot_construct feature that a lambda can be passed in + # instead of a subtree, to compute the partner to be hashed with. + PARTNER_MERKLE_FN = [ + # Combine with itself + lambda h: h, + # Combine with hash 0 + lambda h: bytes([0 for _ in range(32)]), + # Combine with hash 2^256-1 + lambda h: bytes([0xff for _ in range(32)]), + # Combine with itself-1 (BE) + lambda h: (int.from_bytes(h, 'big') - 1).to_bytes(32, 'big'), + # Combine with itself+1 (BE) + lambda h: (int.from_bytes(h, 'big') + 1).to_bytes(32, 'big'), + # Combine with itself-1 (LE) + lambda h: (int.from_bytes(h, 'little') - 1).to_bytes(32, 'big'), + # Combine with itself+1 (LE) + lambda h: (int.from_bytes(h, 'little') + 1).to_bytes(32, 'little'), + # Combine with random bitflipped version of self. + lambda h: (int.from_bytes(h, 'little') ^ (1 << random.randrange(256))).to_bytes(32, 'little') + ] + # Start with a tree of that has depth 1 for "128deep" and depth 2 for "129deep". + scripts = [("128deep", CScript([pubs[0], OP_CHECKSIG])), [("129deep", CScript([pubs[0], OP_CHECKSIG])), random.choice(PARTNER_MERKLE_FN)]] + # Add 127 nodes on top of that tree, so that "128deep" and "129deep" end up at their designated depths. + for _ in range(127): + scripts = [scripts, random.choice(PARTNER_MERKLE_FN)] + tap = taproot_construct(pubs[0], scripts) + # Test that spends with a depth of 128 work, but 129 doesn't (even with a tree with weird Merkle branches in it). + add_spender(spenders, "spendpath/merklelimit", tap=tap, leaf="128deep", **SINGLE_SIG, key=secs[0], failure={"leaf": "129deep"}, **ERR_CONTROLBLOCK_SIZE) + # Test that flipping the negation bit invalidates spends. + add_spender(spenders, "spendpath/negflag", tap=tap, leaf="128deep", **SINGLE_SIG, key=secs[0], failure={"negflag": lambda ctx: 1 - default_negflag(ctx)}, **ERR_WITNESS_PROGRAM_MISMATCH) + # Test that bitflips in the Merkle branch invalidate it. + add_spender(spenders, "spendpath/bitflipmerkle", tap=tap, leaf="128deep", **SINGLE_SIG, key=secs[0], failure={"merklebranch": bitflipper(default_merklebranch)}, **ERR_WITNESS_PROGRAM_MISMATCH) + # Test that bitflips in the inner pubkey invalidate it. + add_spender(spenders, "spendpath/bitflippubkey", tap=tap, leaf="128deep", **SINGLE_SIG, key=secs[0], failure={"pubkey_inner": bitflipper(default_pubkey_inner)}, **ERR_WITNESS_PROGRAM_MISMATCH) + # Test that empty witnesses are invalid. + add_spender(spenders, "spendpath/emptywit", tap=tap, leaf="128deep", **SINGLE_SIG, key=secs[0], failure={"witness": []}, **ERR_EMPTY_WITNESS) + # Test that adding garbage to the control block invalidates it. + add_spender(spenders, "spendpath/padlongcontrol", tap=tap, leaf="128deep", **SINGLE_SIG, key=secs[0], failure={"controlblock": lambda ctx: default_controlblock(ctx) + random_bytes(random.randrange(1, 32))}, **ERR_CONTROLBLOCK_SIZE) + # Test that truncating the control block invalidates it. + add_spender(spenders, "spendpath/trunclongcontrol", tap=tap, leaf="128deep", **SINGLE_SIG, key=secs[0], failure={"controlblock": lambda ctx: default_merklebranch(ctx)[0:random.randrange(1, 32)]}, **ERR_CONTROLBLOCK_SIZE) + + scripts = [("s", CScript([pubs[0], OP_CHECKSIG]))] + tap = taproot_construct(pubs[1], scripts) + # Test that adding garbage to the control block invalidates it. + add_spender(spenders, "spendpath/padshortcontrol", tap=tap, leaf="s", **SINGLE_SIG, key=secs[0], failure={"controlblock": lambda ctx: default_controlblock(ctx) + random_bytes(random.randrange(1, 32))}, **ERR_CONTROLBLOCK_SIZE) + # Test that truncating the control block invalidates it. + add_spender(spenders, "spendpath/truncshortcontrol", tap=tap, leaf="s", **SINGLE_SIG, key=secs[0], failure={"controlblock": lambda ctx: default_merklebranch(ctx)[0:random.randrange(1, 32)]}, **ERR_CONTROLBLOCK_SIZE) + # Test that truncating the control block to 1 byte ("-1 Merkle length") invalidates it + add_spender(spenders, "spendpath/trunc1shortcontrol", tap=tap, leaf="s", **SINGLE_SIG, key=secs[0], failure={"controlblock": lambda ctx: default_merklebranch(ctx)[0:1]}, **ERR_CONTROLBLOCK_SIZE) + + # == Test BIP342 edge cases == + + csa_low_val = random.randrange(0, 17) # Within range for OP_n + csa_low_result = csa_low_val + 1 + + csa_high_val = random.randrange(17, 100) if random.getrandbits(1) else random.randrange(-100, -1) # Outside OP_n range + csa_high_result = csa_high_val + 1 + + OVERSIZE_NUMBER = 2**31 + assert_equal(len(CScriptNum.encode(CScriptNum(OVERSIZE_NUMBER))), 6) + assert_equal(len(CScriptNum.encode(CScriptNum(OVERSIZE_NUMBER-1))), 5) + + big_choices = [] + big_scriptops = [] + for i in range(1000): + r = random.randrange(len(pubs)) + big_choices.append(r) + big_scriptops += [pubs[r], OP_CHECKSIGVERIFY] + + + def big_spend_inputs(ctx): + """Helper function to construct the script input for t33/t34 below.""" + # Instead of signing 999 times, precompute signatures for every (key, hashtype) combination + sigs = {} + for ht in VALID_SIGHASHES_TAPROOT: + for k in range(len(pubs)): + sigs[(k, ht)] = override(default_sign, hashtype=ht, key=secs[k])(ctx) + num = get(ctx, "num") + return [sigs[(big_choices[i], random.choice(VALID_SIGHASHES_TAPROOT))] for i in range(num - 1, -1, -1)] + + # Various BIP342 features + scripts = [ + # 0) drop stack element and OP_CHECKSIG + ("t0", CScript([OP_DROP, pubs[1], OP_CHECKSIG])), + # 1) normal OP_CHECKSIG + ("t1", CScript([pubs[1], OP_CHECKSIG])), + # 2) normal OP_CHECKSIGVERIFY + ("t2", CScript([pubs[1], OP_CHECKSIGVERIFY, OP_1])), + # 3) Hypothetical OP_CHECKMULTISIG script that takes a single sig as input + ("t3", CScript([OP_0, OP_SWAP, OP_1, pubs[1], OP_1, OP_CHECKMULTISIG])), + # 4) Hypothetical OP_CHECKMULTISIGVERIFY script that takes a single sig as input + ("t4", CScript([OP_0, OP_SWAP, OP_1, pubs[1], OP_1, OP_CHECKMULTISIGVERIFY, OP_1])), + # 5) OP_IF script that needs a true input + ("t5", CScript([OP_IF, pubs[1], OP_CHECKSIG, OP_ELSE, OP_RETURN, OP_ENDIF])), + # 6) OP_NOTIF script that needs a true input + ("t6", CScript([OP_NOTIF, OP_RETURN, OP_ELSE, pubs[1], OP_CHECKSIG, OP_ENDIF])), + # 7) OP_CHECKSIG with an empty key + ("t7", CScript([OP_0, OP_CHECKSIG])), + # 8) OP_CHECKSIGVERIFY with an empty key + ("t8", CScript([OP_0, OP_CHECKSIGVERIFY, OP_1])), + # 9) normal OP_CHECKSIGADD that also ensures return value is correct + ("t9", CScript([csa_low_val, pubs[1], OP_CHECKSIGADD, csa_low_result, OP_EQUAL])), + # 10) OP_CHECKSIGADD with empty key + ("t10", CScript([csa_low_val, OP_0, OP_CHECKSIGADD, csa_low_result, OP_EQUAL])), + # 11) OP_CHECKSIGADD with missing counter stack element + ("t11", CScript([pubs[1], OP_CHECKSIGADD, OP_1, OP_EQUAL])), + # 12) OP_CHECKSIG that needs invalid signature + ("t12", CScript([pubs[1], OP_CHECKSIGVERIFY, pubs[0], OP_CHECKSIG, OP_NOT])), + # 13) OP_CHECKSIG with empty key that needs invalid signature + ("t13", CScript([pubs[1], OP_CHECKSIGVERIFY, OP_0, OP_CHECKSIG, OP_NOT])), + # 14) OP_CHECKSIGADD that needs invalid signature + ("t14", CScript([pubs[1], OP_CHECKSIGVERIFY, OP_0, pubs[0], OP_CHECKSIGADD, OP_NOT])), + # 15) OP_CHECKSIGADD with empty key that needs invalid signature + ("t15", CScript([pubs[1], OP_CHECKSIGVERIFY, OP_0, OP_0, OP_CHECKSIGADD, OP_NOT])), + # 16) OP_CHECKSIG with unknown pubkey type + ("t16", CScript([OP_1, OP_CHECKSIG])), + # 17) OP_CHECKSIGADD with unknown pubkey type + ("t17", CScript([OP_0, OP_1, OP_CHECKSIGADD])), + # 18) OP_CHECKSIGVERIFY with unknown pubkey type + ("t18", CScript([OP_1, OP_CHECKSIGVERIFY, OP_1])), + # 19) script longer than 10000 bytes and over 201 non-push opcodes + ("t19", CScript([OP_0, OP_0, OP_2DROP] * 10001 + [pubs[1], OP_CHECKSIG])), + # 20) OP_CHECKSIGVERIFY with empty key + ("t20", CScript([pubs[1], OP_CHECKSIGVERIFY, OP_0, OP_0, OP_CHECKSIGVERIFY, OP_1])), + # 21) Script that grows the stack to 1000 elements + ("t21", CScript([pubs[1], OP_CHECKSIGVERIFY, OP_1] + [OP_DUP] * 999 + [OP_DROP] * 999)), + # 22) Script that grows the stack to 1001 elements + ("t22", CScript([pubs[1], OP_CHECKSIGVERIFY, OP_1] + [OP_DUP] * 1000 + [OP_DROP] * 1000)), + # 23) Script that expects an input stack of 1000 elements + ("t23", CScript([OP_DROP] * 999 + [pubs[1], OP_CHECKSIG])), + # 24) Script that expects an input stack of 1001 elements + ("t24", CScript([OP_DROP] * 1000 + [pubs[1], OP_CHECKSIG])), + # 25) Script that pushes a MAX_SCRIPT_ELEMENT_SIZE-bytes element + ("t25", CScript([random_bytes(MAX_SCRIPT_ELEMENT_SIZE), OP_DROP, pubs[1], OP_CHECKSIG])), + # 26) Script that pushes a (MAX_SCRIPT_ELEMENT_SIZE+1)-bytes element + ("t26", CScript([random_bytes(MAX_SCRIPT_ELEMENT_SIZE+1), OP_DROP, pubs[1], OP_CHECKSIG])), + # 27) CHECKSIGADD that must fail because numeric argument number is >4 bytes + ("t27", CScript([CScriptNum(OVERSIZE_NUMBER), pubs[1], OP_CHECKSIGADD])), + # 28) Pushes random CScriptNum value, checks OP_CHECKSIGADD result + ("t28", CScript([csa_high_val, pubs[1], OP_CHECKSIGADD, csa_high_result, OP_EQUAL])), + # 29) CHECKSIGADD that succeeds with proper sig because numeric argument number is <=4 bytes + ("t29", CScript([CScriptNum(OVERSIZE_NUMBER-1), pubs[1], OP_CHECKSIGADD])), + # 30) Variant of t1 with "normal" 33-byte pubkey + ("t30", CScript([b'\x03' + pubs[1], OP_CHECKSIG])), + # 31) Variant of t2 with "normal" 33-byte pubkey + ("t31", CScript([b'\x02' + pubs[1], OP_CHECKSIGVERIFY, OP_1])), + # 32) Variant of t28 with "normal" 33-byte pubkey + ("t32", CScript([csa_high_val, b'\x03' + pubs[1], OP_CHECKSIGADD, csa_high_result, OP_EQUAL])), + # 33) 999-of-999 multisig + ("t33", CScript(big_scriptops[:1998] + [OP_1])), + # 34) 1000-of-1000 multisig + ("t34", CScript(big_scriptops[:2000] + [OP_1])), + # 35) Variant of t9 that uses a non-minimally encoded input arg + ("t35", CScript([bytes([csa_low_val]), pubs[1], OP_CHECKSIGADD, csa_low_result, OP_EQUAL])), + # 36) Empty script + ("t36", CScript([])), + ] + # Add many dummies to test huge trees + for j in range(100000): + scripts.append((None, CScript([OP_RETURN, random.randrange(100000)]))) + random.shuffle(scripts) + tap = taproot_construct(pubs[0], scripts) + common = { + "hashtype": hashtype, + "key": secs[1], + "tap": tap, + } + # Test that MAX_SCRIPT_ELEMENT_SIZE byte stack element inputs are valid, but not one more (and 80 bytes is standard but 81 is not). + add_spender(spenders, "tapscript/inputmaxlimit", leaf="t0", **common, standard=False, inputs=[getter("sign"), random_bytes(MAX_SCRIPT_ELEMENT_SIZE)], failure={"inputs": [getter("sign"), random_bytes(MAX_SCRIPT_ELEMENT_SIZE+1)]}, **ERR_PUSH_LIMIT) + add_spender(spenders, "tapscript/input80limit", leaf="t0", **common, inputs=[getter("sign"), random_bytes(80)]) + add_spender(spenders, "tapscript/input81limit", leaf="t0", **common, standard=False, inputs=[getter("sign"), random_bytes(81)]) + # Test that OP_CHECKMULTISIG and OP_CHECKMULTISIGVERIFY cause failure, but OP_CHECKSIG and OP_CHECKSIGVERIFY work. + add_spender(spenders, "tapscript/disabled_checkmultisig", leaf="t1", **common, **SINGLE_SIG, failure={"leaf": "t3"}, **ERR_TAPSCRIPT_CHECKMULTISIG) + add_spender(spenders, "tapscript/disabled_checkmultisigverify", leaf="t2", **common, **SINGLE_SIG, failure={"leaf": "t4"}, **ERR_TAPSCRIPT_CHECKMULTISIG) + # Test that OP_IF and OP_NOTIF do not accept non-0x01 as truth value (the MINIMALIF rule is consensus in Tapscript) + add_spender(spenders, "tapscript/minimalif", leaf="t5", **common, inputs=[getter("sign"), b'\x01'], failure={"inputs": [getter("sign"), b'\x02']}, **ERR_MINIMALIF) + add_spender(spenders, "tapscript/minimalnotif", leaf="t6", **common, inputs=[getter("sign"), b'\x01'], failure={"inputs": [getter("sign"), b'\x03']}, **ERR_MINIMALIF) + add_spender(spenders, "tapscript/minimalif", leaf="t5", **common, inputs=[getter("sign"), b'\x01'], failure={"inputs": [getter("sign"), b'\x0001']}, **ERR_MINIMALIF) + add_spender(spenders, "tapscript/minimalnotif", leaf="t6", **common, inputs=[getter("sign"), b'\x01'], failure={"inputs": [getter("sign"), b'\x0100']}, **ERR_MINIMALIF) + # Test that 1-byte public keys (which are unknown) are acceptable but nonstandard with unrelated signatures, but 0-byte public keys are not valid. + add_spender(spenders, "tapscript/unkpk/checksig", leaf="t16", standard=False, **common, **SINGLE_SIG, failure={"leaf": "t7"}, **ERR_UNKNOWN_PUBKEY) + add_spender(spenders, "tapscript/unkpk/checksigadd", leaf="t17", standard=False, **common, **SINGLE_SIG, failure={"leaf": "t10"}, **ERR_UNKNOWN_PUBKEY) + add_spender(spenders, "tapscript/unkpk/checksigverify", leaf="t18", standard=False, **common, **SINGLE_SIG, failure={"leaf": "t8"}, **ERR_UNKNOWN_PUBKEY) + # Test that 33-byte public keys (which are unknown) are acceptable but nonstandard with valid signatures, but normal pubkeys are not valid in that case. + add_spender(spenders, "tapscript/oldpk/checksig", leaf="t30", standard=False, **common, **SINGLE_SIG, sighash=bitflipper(default_sighash), failure={"leaf": "t1"}, **ERR_SIG_SCHNORR) + add_spender(spenders, "tapscript/oldpk/checksigadd", leaf="t31", standard=False, **common, **SINGLE_SIG, sighash=bitflipper(default_sighash), failure={"leaf": "t2"}, **ERR_SIG_SCHNORR) + add_spender(spenders, "tapscript/oldpk/checksigverify", leaf="t32", standard=False, **common, **SINGLE_SIG, sighash=bitflipper(default_sighash), failure={"leaf": "t28"}, **ERR_SIG_SCHNORR) + # Test that 0-byte public keys are not acceptable. + add_spender(spenders, "tapscript/emptypk/checksig", leaf="t1", **SINGLE_SIG, **common, failure={"leaf": "t7"}, **ERR_UNKNOWN_PUBKEY) + add_spender(spenders, "tapscript/emptypk/checksigverify", leaf="t2", **SINGLE_SIG, **common, failure={"leaf": "t8"}, **ERR_UNKNOWN_PUBKEY) + add_spender(spenders, "tapscript/emptypk/checksigadd", leaf="t9", **SINGLE_SIG, **common, failure={"leaf": "t10"}, **ERR_UNKNOWN_PUBKEY) + add_spender(spenders, "tapscript/emptypk/checksigadd", leaf="t35", standard=False, **SINGLE_SIG, **common, failure={"leaf": "t10"}, **ERR_UNKNOWN_PUBKEY) + # Test that OP_CHECKSIGADD results are as expected + add_spender(spenders, "tapscript/checksigaddresults", leaf="t28", **SINGLE_SIG, **common, failure={"leaf": "t27"}, err_msg="unknown error") + add_spender(spenders, "tapscript/checksigaddoversize", leaf="t29", **SINGLE_SIG, **common, failure={"leaf": "t27"}, err_msg="unknown error") + # Test that OP_CHECKSIGADD requires 3 stack elements. + add_spender(spenders, "tapscript/checksigadd3args", leaf="t9", **SINGLE_SIG, **common, failure={"leaf": "t11"}, **ERR_STACK_EMPTY) + # Test that empty signatures do not cause script failure in OP_CHECKSIG and OP_CHECKSIGADD (but do fail with empty pubkey, and do fail OP_CHECKSIGVERIFY) + add_spender(spenders, "tapscript/emptysigs/checksig", leaf="t12", **common, inputs=[b'', getter("sign")], failure={"leaf": "t13"}, **ERR_UNKNOWN_PUBKEY) + add_spender(spenders, "tapscript/emptysigs/nochecksigverify", leaf="t12", **common, inputs=[b'', getter("sign")], failure={"leaf": "t20"}, **ERR_UNKNOWN_PUBKEY) + add_spender(spenders, "tapscript/emptysigs/checksigadd", leaf="t14", **common, inputs=[b'', getter("sign")], failure={"leaf": "t15"}, **ERR_UNKNOWN_PUBKEY) + # Test that scripts over 10000 bytes (and over 201 non-push ops) are acceptable. + add_spender(spenders, "tapscript/no10000limit", leaf="t19", **SINGLE_SIG, **common) + # Test that a stack size of 1000 elements is permitted, but 1001 isn't. + add_spender(spenders, "tapscript/1000stack", leaf="t21", **SINGLE_SIG, **common, failure={"leaf": "t22"}, **ERR_STACK_SIZE) + # Test that an input stack size of 1000 elements is permitted, but 1001 isn't. + add_spender(spenders, "tapscript/1000inputs", leaf="t23", **common, inputs=[getter("sign")] + [b'' for _ in range(999)], failure={"leaf": "t24", "inputs": [getter("sign")] + [b'' for _ in range(1000)]}, **ERR_STACK_SIZE) + # Test that pushing a MAX_SCRIPT_ELEMENT_SIZE byte stack element is valid, but one longer is not. + add_spender(spenders, "tapscript/pushmaxlimit", leaf="t25", **common, **SINGLE_SIG, failure={"leaf": "t26"}, **ERR_PUSH_LIMIT) + # Test that 999-of-999 multisig works (but 1000-of-1000 triggers stack size limits) + add_spender(spenders, "tapscript/bigmulti", leaf="t33", **common, inputs=big_spend_inputs, num=999, failure={"leaf": "t34", "num": 1000}, **ERR_STACK_SIZE) + # Test that the CLEANSTACK rule is consensus critical in tapscript + add_spender(spenders, "tapscript/cleanstack", leaf="t36", tap=tap, inputs=[b'\x01'], failure={"inputs": [b'\x01', b'\x01']}, **ERR_CLEANSTACK) + + # == Test for sigops ratio limit == + + # Given a number n, and a public key pk, functions that produce a (CScript, sigops). Each script takes as + # input a valid signature with the passed pk followed by a dummy push of bytes that are to be dropped, and + # will execute sigops signature checks. + SIGOPS_RATIO_SCRIPTS = [ + # n OP_CHECKSIGVERFIYs and 1 OP_CHECKSIG. + lambda n, pk: (CScript([OP_DROP, pk] + [OP_2DUP, OP_CHECKSIGVERIFY] * n + [OP_CHECKSIG]), n + 1), + # n OP_CHECKSIGVERIFYs and 1 OP_CHECKSIGADD, but also one unexecuted OP_CHECKSIGVERIFY. + lambda n, pk: (CScript([OP_DROP, pk, OP_0, OP_IF, OP_2DUP, OP_CHECKSIGVERIFY, OP_ENDIF] + [OP_2DUP, OP_CHECKSIGVERIFY] * n + [OP_2, OP_SWAP, OP_CHECKSIGADD, OP_3, OP_EQUAL]), n + 1), + # n OP_CHECKSIGVERIFYs and 1 OP_CHECKSIGADD, but also one unexecuted OP_CHECKSIG. + lambda n, pk: (CScript([random_bytes(220), OP_2DROP, pk, OP_1, OP_NOTIF, OP_2DUP, OP_CHECKSIG, OP_VERIFY, OP_ENDIF] + [OP_2DUP, OP_CHECKSIGVERIFY] * n + [OP_4, OP_SWAP, OP_CHECKSIGADD, OP_5, OP_EQUAL]), n + 1), + # n OP_CHECKSIGVERFIYs and 1 OP_CHECKSIGADD, but also one unexecuted OP_CHECKSIGADD. + lambda n, pk: (CScript([OP_DROP, pk, OP_1, OP_IF, OP_ELSE, OP_2DUP, OP_6, OP_SWAP, OP_CHECKSIGADD, OP_7, OP_EQUALVERIFY, OP_ENDIF] + [OP_2DUP, OP_CHECKSIGVERIFY] * n + [OP_8, OP_SWAP, OP_CHECKSIGADD, OP_9, OP_EQUAL]), n + 1), + # n+1 OP_CHECKSIGs, but also one OP_CHECKSIG with an empty signature. + lambda n, pk: (CScript([OP_DROP, OP_0, pk, OP_CHECKSIG, OP_NOT, OP_VERIFY, pk] + [OP_2DUP, OP_CHECKSIG, OP_VERIFY] * n + [OP_CHECKSIG]), n + 1), + # n OP_CHECKSIGADDs and 1 OP_CHECKSIG, but also an OP_CHECKSIGADD with an empty signature. + lambda n, pk: (CScript([OP_DROP, OP_0, OP_10, pk, OP_CHECKSIGADD, OP_10, OP_EQUALVERIFY, pk] + [OP_2DUP, OP_16, OP_SWAP, OP_CHECKSIGADD, b'\x11', OP_EQUALVERIFY] * n + [OP_CHECKSIG]), n + 1), + ] + for annex in [None, bytes([ANNEX_TAG]) + random_bytes(random.randrange(1000))]: + for hashtype in [SIGHASH_DEFAULT, SIGHASH_ALL]: + for pubkey in [pubs[1], random_bytes(random.choice([x for x in range(2, 81) if x != 32]))]: + for fn_num, fn in enumerate(SIGOPS_RATIO_SCRIPTS): + merkledepth = random.randrange(129) + + + def predict_sigops_ratio(n, dummy_size): + """Predict whether spending fn(n, pubkey) with dummy_size will pass the ratio test.""" + script, sigops = fn(n, pubkey) + # Predict the size of the witness for a given choice of n + stacklen_size = 1 + sig_size = 64 + (hashtype != SIGHASH_DEFAULT) + siglen_size = 1 + dummylen_size = 1 + 2 * (dummy_size >= 253) + script_size = len(script) + scriptlen_size = 1 + 2 * (script_size >= 253) + control_size = 33 + 32 * merkledepth + controllen_size = 1 + 2 * (control_size >= 253) + annex_size = 0 if annex is None else len(annex) + annexlen_size = 0 if annex is None else 1 + 2 * (annex_size >= 253) + witsize = stacklen_size + sig_size + siglen_size + dummy_size + dummylen_size + script_size + scriptlen_size + control_size + controllen_size + annex_size + annexlen_size + # sigops ratio test + return witsize + 50 >= 50 * sigops + # Make sure n is high enough that with empty dummy, the script is not valid + n = 0 + while predict_sigops_ratio(n, 0): + n += 1 + # But allow picking a bit higher still + n += random.randrange(5) + # Now pick dummy size *just* large enough that the overall construction passes + dummylen = 0 + while not predict_sigops_ratio(n, dummylen): + dummylen += 1 + scripts = [("s", fn(n, pubkey)[0])] + for _ in range(merkledepth): + scripts = [scripts, random.choice(PARTNER_MERKLE_FN)] + tap = taproot_construct(pubs[0], scripts) + standard = annex is None and dummylen <= 80 and len(pubkey) == 32 + add_spender(spenders, "tapscript/sigopsratio_%i" % fn_num, tap=tap, leaf="s", annex=annex, hashtype=hashtype, key=secs[1], inputs=[getter("sign"), random_bytes(dummylen)], standard=standard, failure={"inputs": [getter("sign"), random_bytes(dummylen - 1)]}, **ERR_SIGOPS_RATIO) + + # Future leaf versions + for leafver in range(0, 0x100, 2): + if leafver == LEAF_VERSION_TAPSCRIPT or leafver == ANNEX_TAG: + # Skip the defined LEAF_VERSION_TAPSCRIPT, and the ANNEX_TAG which is not usable as leaf version + continue + scripts = [ + ("bare_c0", CScript([OP_NOP])), + ("bare_unkver", CScript([OP_NOP]), leafver), + ("return_c0", CScript([OP_RETURN])), + ("return_unkver", CScript([OP_RETURN]), leafver), + ("undecodable_c0", CScript([OP_PUSHDATA1])), + ("undecodable_unkver", CScript([OP_PUSHDATA1]), leafver), + ("bigpush_c0", CScript([random_bytes(MAX_SCRIPT_ELEMENT_SIZE+1), OP_DROP])), + ("bigpush_unkver", CScript([random_bytes(MAX_SCRIPT_ELEMENT_SIZE+1), OP_DROP]), leafver), + ("1001push_c0", CScript([OP_0] * 1001)), + ("1001push_unkver", CScript([OP_0] * 1001), leafver), + ] + random.shuffle(scripts) + tap = taproot_construct(pubs[0], scripts) + add_spender(spenders, "unkver/bare", standard=False, tap=tap, leaf="bare_unkver", failure={"leaf": "bare_c0"}, **ERR_CLEANSTACK) + add_spender(spenders, "unkver/return", standard=False, tap=tap, leaf="return_unkver", failure={"leaf": "return_c0"}, **ERR_OP_RETURN) + add_spender(spenders, "unkver/undecodable", standard=False, tap=tap, leaf="undecodable_unkver", failure={"leaf": "undecodable_c0"}, **ERR_UNDECODABLE) + add_spender(spenders, "unkver/bigpush", standard=False, tap=tap, leaf="bigpush_unkver", failure={"leaf": "bigpush_c0"}, **ERR_PUSH_LIMIT) + add_spender(spenders, "unkver/1001push", standard=False, tap=tap, leaf="1001push_unkver", failure={"leaf": "1001push_c0"}, **ERR_STACK_SIZE) + add_spender(spenders, "unkver/1001inputs", standard=False, tap=tap, leaf="bare_unkver", inputs=[b'']*1001, failure={"leaf": "bare_c0"}, **ERR_STACK_SIZE) + + # OP_SUCCESSx tests. + hashtype = lambda _: random.choice(VALID_SIGHASHES_TAPROOT) + for opval in range(76, 0x100): + opcode = CScriptOp(opval) + if not is_op_success(opcode): + continue + scripts = [ + ("bare_success", CScript([opcode])), + ("bare_nop", CScript([OP_NOP])), + ("unexecif_success", CScript([OP_0, OP_IF, opcode, OP_ENDIF])), + ("unexecif_nop", CScript([OP_0, OP_IF, OP_NOP, OP_ENDIF])), + ("return_success", CScript([OP_RETURN, opcode])), + ("return_nop", CScript([OP_RETURN, OP_NOP])), + ("undecodable_success", CScript([opcode, OP_PUSHDATA1])), + ("undecodable_nop", CScript([OP_NOP, OP_PUSHDATA1])), + ("undecodable_bypassed_success", CScript([OP_PUSHDATA1, OP_2, opcode])), + ("bigpush_success", CScript([random_bytes(MAX_SCRIPT_ELEMENT_SIZE+1), OP_DROP, opcode])), + ("bigpush_nop", CScript([random_bytes(MAX_SCRIPT_ELEMENT_SIZE+1), OP_DROP, OP_NOP])), + ("1001push_success", CScript([OP_0] * 1001 + [opcode])), + ("1001push_nop", CScript([OP_0] * 1001 + [OP_NOP])), + ] + random.shuffle(scripts) + tap = taproot_construct(pubs[0], scripts) + add_spender(spenders, "opsuccess/bare", standard=False, tap=tap, leaf="bare_success", failure={"leaf": "bare_nop"}, **ERR_CLEANSTACK) + add_spender(spenders, "opsuccess/unexecif", standard=False, tap=tap, leaf="unexecif_success", failure={"leaf": "unexecif_nop"}, **ERR_CLEANSTACK) + add_spender(spenders, "opsuccess/return", standard=False, tap=tap, leaf="return_success", failure={"leaf": "return_nop"}, **ERR_OP_RETURN) + add_spender(spenders, "opsuccess/undecodable", standard=False, tap=tap, leaf="undecodable_success", failure={"leaf": "undecodable_nop"}, **ERR_UNDECODABLE) + add_spender(spenders, "opsuccess/undecodable_bypass", standard=False, tap=tap, leaf="undecodable_success", failure={"leaf": "undecodable_bypassed_success"}, **ERR_UNDECODABLE) + add_spender(spenders, "opsuccess/bigpush", standard=False, tap=tap, leaf="bigpush_success", failure={"leaf": "bigpush_nop"}, **ERR_PUSH_LIMIT) + add_spender(spenders, "opsuccess/1001push", standard=False, tap=tap, leaf="1001push_success", failure={"leaf": "1001push_nop"}, **ERR_STACK_SIZE) + add_spender(spenders, "opsuccess/1001inputs", standard=False, tap=tap, leaf="bare_success", inputs=[b'']*1001, failure={"leaf": "bare_nop"}, **ERR_STACK_SIZE) + + # Non-OP_SUCCESSx (verify that those aren't accidentally treated as OP_SUCCESSx) + for opval in range(0, 0x100): + opcode = CScriptOp(opval) + if is_op_success(opcode): + continue + scripts = [ + ("normal", CScript([OP_RETURN, opcode] + [OP_NOP] * 75)), + ("op_success", CScript([OP_RETURN, CScriptOp(0x50)])) + ] + tap = taproot_construct(pubs[0], scripts) + add_spender(spenders, "alwaysvalid/notsuccessx", tap=tap, leaf="op_success", inputs=[], standard=False, failure={"leaf": "normal"}) # err_msg differs based on opcode + + # == Legacy tests == + + # Also add a few legacy spends into the mix, so that transactions which combine taproot and pre-taproot spends get tested too. + for compressed in [False, True]: + eckey1 = ECKey() + eckey1.set(generate_privkey(), compressed) + pubkey1 = eckey1.get_pubkey().get_bytes() + eckey2 = ECKey() + eckey2.set(generate_privkey(), compressed) + for p2sh in [False, True]: + for witv0 in [False, True]: + for hashtype in VALID_SIGHASHES_ECDSA + [random.randrange(0x04, 0x80), random.randrange(0x84, 0x100)]: + standard = (hashtype in VALID_SIGHASHES_ECDSA) and (compressed or not witv0) + add_spender(spenders, "legacy/pk-wrongkey", hashtype=hashtype, p2sh=p2sh, witv0=witv0, standard=standard, script=CScript([pubkey1, OP_CHECKSIG]), **SINGLE_SIG, key=eckey1, failure={"key": eckey2}, sigops_weight=4-3*witv0, **ERR_NO_SUCCESS) + add_spender(spenders, "legacy/pkh-sighashflip", hashtype=hashtype, p2sh=p2sh, witv0=witv0, standard=standard, pkh=pubkey1, key=eckey1, **SIGHASH_BITFLIP, sigops_weight=4-3*witv0, **ERR_NO_SUCCESS) + + # Verify that OP_CHECKSIGADD wasn't accidentally added to pre-taproot validation logic. + for p2sh in [False, True]: + for witv0 in [False, True]: + for hashtype in VALID_SIGHASHES_ECDSA + [random.randrange(0x04, 0x80), random.randrange(0x84, 0x100)]: + standard = hashtype in VALID_SIGHASHES_ECDSA and (p2sh or witv0) + add_spender(spenders, "compat/nocsa", hashtype=hashtype, p2sh=p2sh, witv0=witv0, standard=standard, script=CScript([OP_IF, OP_11, pubkey1, OP_CHECKSIGADD, OP_12, OP_EQUAL, OP_ELSE, pubkey1, OP_CHECKSIG, OP_ENDIF]), key=eckey1, sigops_weight=4-3*witv0, inputs=[getter("sign"), b''], failure={"inputs": [getter("sign"), b'\x01']}, **ERR_UNDECODABLE) + + return spenders + +def spenders_taproot_inactive(): + """Spenders for testing that pre-activation Taproot rules don't apply.""" + + spenders = [] + + sec = generate_privkey() + pub, _ = compute_xonly_pubkey(sec) + scripts = [ + ("pk", CScript([pub, OP_CHECKSIG])), + ("future_leaf", CScript([pub, OP_CHECKSIG]), 0xc2), + ("op_success", CScript([pub, OP_CHECKSIG, OP_0, OP_IF, CScriptOp(0x50), OP_ENDIF])), + ] + tap = taproot_construct(pub, scripts) + + # Test that keypath spending is valid & standard if compliant, but valid and nonstandard otherwise. + add_spender(spenders, "inactive/keypath_valid", key=sec, tap=tap) + add_spender(spenders, "inactive/keypath_invalidsig", key=sec, tap=tap, standard=False, sighash=bitflipper(default_sighash)) + add_spender(spenders, "inactive/keypath_empty", key=sec, tap=tap, standard=False, witness=[]) + + # Same for scriptpath spending (but using future features like annex, leaf versions, or OP_SUCCESS is nonstandard). + add_spender(spenders, "inactive/scriptpath_valid", key=sec, tap=tap, leaf="pk", inputs=[getter("sign")]) + add_spender(spenders, "inactive/scriptpath_invalidsig", key=sec, tap=tap, leaf="pk", standard=False, inputs=[getter("sign")], sighash=bitflipper(default_sighash)) + add_spender(spenders, "inactive/scriptpath_invalidcb", key=sec, tap=tap, leaf="pk", standard=False, inputs=[getter("sign")], controlblock=bitflipper(default_controlblock)) + add_spender(spenders, "inactive/scriptpath_valid_unkleaf", key=sec, tap=tap, leaf="future_leaf", standard=False, inputs=[getter("sign")]) + add_spender(spenders, "inactive/scriptpath_invalid_unkleaf", key=sec, tap=tap, leaf="future_leaf", standard=False, inputs=[getter("sign")], sighash=bitflipper(default_sighash)) + add_spender(spenders, "inactive/scriptpath_valid_opsuccess", key=sec, tap=tap, leaf="op_success", standard=False, inputs=[getter("sign")]) + add_spender(spenders, "inactive/scriptpath_valid_opsuccess", key=sec, tap=tap, leaf="op_success", standard=False, inputs=[getter("sign")], sighash=bitflipper(default_sighash)) + + return spenders + +# Data type to keep track of UTXOs, where they were created, and how to spend them. +UTXOData = namedtuple('UTXOData', 'outpoint,output,spender') + +class TaprootTest(BitcoinTestFramework): + + def skip_test_if_missing_module(self): + self.skip_if_no_wallet() + + def set_test_params(self): + self.num_nodes = 2 + self.setup_clean_chain = True + # Node 0 has Taproot inactive, Node 1 active. + self.extra_args = [["-whitelist=127.0.0.1", "-par=1", "-vbparams=taproot:1:1"], ["-whitelist=127.0.0.1", "-par=1"]] + + def block_submit(self, node, txs, msg, err_msg, cb_pubkey=None, fees=0, sigops_weight=0, witness=False, accept=False): + + # Deplete block of any non-tapscript sigops using a single additional 0-value coinbase output. + # It is not impossible to fit enough tapscript sigops to hit the old 80k limit without + # busting txin-level limits. We simply have to account for the p2pk outputs in all + # transactions. + extra_output_script = CScript([OP_CHECKSIG]*((MAX_BLOCK_SIGOPS_WEIGHT - sigops_weight) // WITNESS_SCALE_FACTOR)) + + block = create_block(self.tip, create_coinbase(self.lastblockheight + 1, pubkey=cb_pubkey, extra_output_script=extra_output_script, fees=fees), self.lastblocktime + 1) + block.nVersion = 4 + for tx in txs: + tx.rehash() + block.vtx.append(tx) + block.hashMerkleRoot = block.calc_merkle_root() + witness and add_witness_commitment(block) + block.rehash() + block.solve() + block_response = node.submitblock(block.serialize(True).hex()) + if err_msg is not None: + assert block_response is not None and err_msg in block_response, "Missing error message '%s' from block response '%s': %s" % (err_msg, "(None)" if block_response is None else block_response, msg) + if (accept): + assert node.getbestblockhash() == block.hash, "Failed to accept: %s (response: %s)" % (msg, block_response) + self.tip = block.sha256 + self.lastblockhash = block.hash + self.lastblocktime += 1 + self.lastblockheight += 1 + else: + assert node.getbestblockhash() == self.lastblockhash, "Failed to reject: " + msg + + def test_spenders(self, node, spenders, input_counts): + """Run randomized tests with a number of "spenders". + + Steps: + 1) Generate an appropriate UTXO for each spender to test spend conditions + 2) Generate 100 random addresses of all wallet types: pkh/sh_wpkh/wpkh + 3) Select random number of inputs from (1) + 4) Select random number of addresses from (2) as outputs + + Each spender embodies a test; in a large randomized test, it is verified + that toggling the valid argument to each lambda toggles the validity of + the transaction. This is accomplished by constructing transactions consisting + of all valid inputs, except one invalid one. + """ + + # Construct a bunch of sPKs that send coins back to the host wallet + self.log.info("- Constructing addresses for returning coins") + host_spks = [] + host_pubkeys = [] + for i in range(16): + addr = node.getnewaddress(address_type=random.choice(["legacy", "p2sh-segwit", "bech32"])) + info = node.getaddressinfo(addr) + spk = bytes.fromhex(info['scriptPubKey']) + host_spks.append(spk) + host_pubkeys.append(bytes.fromhex(info['pubkey'])) + + # Initialize variables used by block_submit(). + self.lastblockhash = node.getbestblockhash() + self.tip = int(self.lastblockhash, 16) + block = node.getblock(self.lastblockhash) + self.lastblockheight = block['height'] + self.lastblocktime = block['time'] + + # Create transactions spending up to 50 of the wallet's inputs, with one output for each spender, and + # one change output at the end. The transaction is constructed on the Python side to enable + # having multiple outputs to the same address and outputs with no assigned address. The wallet + # is then asked to sign it through signrawtransactionwithwallet, and then added to a block on the + # Python side (to bypass standardness rules). + self.log.info("- Creating test UTXOs...") + random.shuffle(spenders) + normal_utxos = [] + mismatching_utxos = [] # UTXOs with input that requires mismatching output position + done = 0 + while done < len(spenders): + # Compute how many UTXOs to create with this transaction + count_this_tx = min(len(spenders) - done, (len(spenders) + 4) // 5, 10000) + + fund_tx = CTransaction() + # Add the 50 highest-value inputs + unspents = node.listunspent() + random.shuffle(unspents) + unspents.sort(key=lambda x: int(x["amount"] * 100000000), reverse=True) + if len(unspents) > 50: + unspents = unspents[:50] + random.shuffle(unspents) + balance = 0 + for unspent in unspents: + balance += int(unspent["amount"] * 100000000) + txid = int(unspent["txid"], 16) + fund_tx.vin.append(CTxIn(COutPoint(txid, int(unspent["vout"])), CScript())) + # Add outputs + cur_progress = done / len(spenders) + next_progress = (done + count_this_tx) / len(spenders) + change_goal = (1.0 - 0.6 * next_progress) / (1.0 - 0.6 * cur_progress) * balance + self.log.debug("Create %i UTXOs in a transaction spending %i inputs worth %.8f (sending ~%.8f to change)" % (count_this_tx, len(unspents), balance * 0.00000001, change_goal * 0.00000001)) + for i in range(count_this_tx): + avg = (balance - change_goal) / (count_this_tx - i) + amount = int(random.randrange(int(avg*0.85 + 0.5), int(avg*1.15 + 0.5)) + 0.5) + balance -= amount + fund_tx.vout.append(CTxOut(amount, spenders[done + i].script)) + # Add change + fund_tx.vout.append(CTxOut(balance - 10000, random.choice(host_spks))) + # Ask the wallet to sign + ss = BytesIO(bytes.fromhex(node.signrawtransactionwithwallet(ToHex(fund_tx))["hex"])) + fund_tx.deserialize(ss) + # Construct UTXOData entries + fund_tx.rehash() + for i in range(count_this_tx): + utxodata = UTXOData(outpoint=COutPoint(fund_tx.sha256, i), output=fund_tx.vout[i], spender=spenders[done]) + if utxodata.spender.need_vin_vout_mismatch: + mismatching_utxos.append(utxodata) + else: + normal_utxos.append(utxodata) + done += 1 + # Mine into a block + self.block_submit(node, [fund_tx], "Funding tx", None, random.choice(host_pubkeys), 10000, MAX_BLOCK_SIGOPS_WEIGHT, True, True) + + # Consume groups of choice(input_coins) from utxos in a tx, testing the spenders. + self.log.info("- Running %i spending tests" % done) + random.shuffle(normal_utxos) + random.shuffle(mismatching_utxos) + assert done == len(normal_utxos) + len(mismatching_utxos) + + left = done + while left: + # Construct CTransaction with random nVersion, nLocktime + tx = CTransaction() + tx.nVersion = random.choice([1, 2, random.randint(-0x80000000, 0x7fffffff)]) + min_sequence = (tx.nVersion != 1 and tx.nVersion != 0) * 0x80000000 # The minimum sequence number to disable relative locktime + if random.choice([True, False]): + tx.nLockTime = random.randrange(LOCKTIME_THRESHOLD, self.lastblocktime - 7200) # all absolute locktimes in the past + else: + tx.nLockTime = random.randrange(self.lastblockheight + 1) # all block heights in the past + + # Decide how many UTXOs to test with. + acceptable = [n for n in input_counts if n <= left and (left - n > max(input_counts) or (left - n) in [0] + input_counts)] + num_inputs = random.choice(acceptable) + + # If we have UTXOs that require mismatching inputs/outputs left, include exactly one of those + # unless there is only one normal UTXO left (as tests with mismatching UTXOs require at least one + # normal UTXO to go in the first position), and we don't want to run out of normal UTXOs. + input_utxos = [] + while len(mismatching_utxos) and (len(input_utxos) == 0 or len(normal_utxos) == 1): + input_utxos.append(mismatching_utxos.pop()) + left -= 1 + + # Top up until we hit num_inputs (but include at least one normal UTXO always). + for _ in range(max(1, num_inputs - len(input_utxos))): + input_utxos.append(normal_utxos.pop()) + left -= 1 + + # The first input cannot require a mismatching output (as there is at least one output). + while True: + random.shuffle(input_utxos) + if not input_utxos[0].spender.need_vin_vout_mismatch: + break + first_mismatch_input = None + for i in range(len(input_utxos)): + if input_utxos[i].spender.need_vin_vout_mismatch: + first_mismatch_input = i + assert first_mismatch_input is None or first_mismatch_input > 0 + + # Decide fee, and add CTxIns to tx. + amount = sum(utxo.output.nValue for utxo in input_utxos) + fee = min(random.randrange(MIN_FEE * 2, MIN_FEE * 4), amount - DUST_LIMIT) # 10000-20000 sat fee + in_value = amount - fee + tx.vin = [CTxIn(outpoint=utxo.outpoint, nSequence=random.randint(min_sequence, 0xffffffff)) for utxo in input_utxos] + tx.wit.vtxinwit = [CTxInWitness() for _ in range(len(input_utxos))] + sigops_weight = sum(utxo.spender.sigops_weight for utxo in input_utxos) + self.log.debug("Test: %s" % (", ".join(utxo.spender.comment for utxo in input_utxos))) + + # Add 1 to 4 random outputs (but constrained by inputs that require mismatching outputs) + num_outputs = random.choice(range(1, 1 + min(4, 4 if first_mismatch_input is None else first_mismatch_input))) + assert in_value >= 0 and fee - num_outputs * DUST_LIMIT >= MIN_FEE + for i in range(num_outputs): + tx.vout.append(CTxOut()) + if in_value <= DUST_LIMIT: + tx.vout[-1].nValue = DUST_LIMIT + elif i < num_outputs - 1: + tx.vout[-1].nValue = in_value + else: + tx.vout[-1].nValue = random.randint(DUST_LIMIT, in_value) + in_value -= tx.vout[-1].nValue + tx.vout[-1].scriptPubKey = random.choice(host_spks) + sigops_weight += CScript(tx.vout[-1].scriptPubKey).GetSigOpCount(False) * WITNESS_SCALE_FACTOR + fee += in_value + assert fee >= 0 + + # Select coinbase pubkey + cb_pubkey = random.choice(host_pubkeys) + sigops_weight += 1 * WITNESS_SCALE_FACTOR + + # Precompute one satisfying and one failing scriptSig/witness for each input. + input_data = [] + for i in range(len(input_utxos)): + fn = input_utxos[i].spender.sat_function + fail = None + success = fn(tx, i, [utxo.output for utxo in input_utxos], True) + if not input_utxos[i].spender.no_fail: + fail = fn(tx, i, [utxo.output for utxo in input_utxos], False) + input_data.append((fail, success)) + + # Sign each input incorrectly once on each complete signing pass, except the very last. + for fail_input in list(range(len(input_utxos))) + [None]: + # Skip trying to fail at spending something that can't be made to fail. + if fail_input is not None and input_utxos[fail_input].spender.no_fail: + continue + # Expected message with each input failure, may be None(which is ignored) + expected_fail_msg = None if fail_input is None else input_utxos[fail_input].spender.err_msg + # Fill inputs/witnesses + for i in range(len(input_utxos)): + tx.vin[i].scriptSig = input_data[i][i != fail_input][0] + tx.wit.vtxinwit[i].scriptWitness.stack = input_data[i][i != fail_input][1] + # Submit to mempool to check standardness + is_standard_tx = fail_input is None and all(utxo.spender.is_standard for utxo in input_utxos) and tx.nVersion >= 1 and tx.nVersion <= 2 + tx.rehash() + msg = ','.join(utxo.spender.comment + ("*" if n == fail_input else "") for n, utxo in enumerate(input_utxos)) + if is_standard_tx: + node.sendrawtransaction(tx.serialize().hex(), 0) + assert node.getmempoolentry(tx.hash) is not None, "Failed to accept into mempool: " + msg + else: + assert_raises_rpc_error(-26, None, node.sendrawtransaction, tx.serialize().hex(), 0) + # Submit in a block + self.block_submit(node, [tx], msg, witness=True, accept=fail_input is None, cb_pubkey=cb_pubkey, fees=fee, sigops_weight=sigops_weight, err_msg=expected_fail_msg) + + if (len(spenders) - left) // 200 > (len(spenders) - left - len(input_utxos)) // 200: + self.log.info(" - %i tests done" % (len(spenders) - left)) + + assert left == 0 + assert len(normal_utxos) == 0 + assert len(mismatching_utxos) == 0 + self.log.info(" - Done") + + def run_test(self): + self.connect_nodes(0, 1) + + # Post-taproot activation tests go first (pre-taproot tests' blocks are invalid post-taproot). + self.log.info("Post-activation tests...") + self.nodes[1].generate(101) + self.test_spenders(self.nodes[1], spenders_taproot_active(), input_counts=[1, 2, 2, 2, 2, 3]) + + # Transfer % of funds to pre-taproot node. + addr = self.nodes[0].getnewaddress() + self.nodes[1].sendtoaddress(address=addr, amount=int(self.nodes[1].getbalance() * 70000000) / 100000000) + self.nodes[1].generate(1) + self.sync_blocks() + + # Pre-taproot activation tests. + self.log.info("Pre-activation tests...") + self.test_spenders(self.nodes[0], spenders_taproot_inactive(), input_counts=[1, 2, 2, 2, 2, 3]) + + +if __name__ == '__main__': + TaprootTest().main() |