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|
// Copyright (c) 2021-2022 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <core_io.h>
#include <hash.h>
#include <key.h>
#include <script/miniscript.h>
#include <script/script.h>
#include <script/signingprovider.h>
#include <test/fuzz/FuzzedDataProvider.h>
#include <test/fuzz/fuzz.h>
#include <test/fuzz/util.h>
#include <util/strencodings.h>
namespace {
using Fragment = miniscript::Fragment;
using NodeRef = miniscript::NodeRef<CPubKey>;
using Node = miniscript::Node<CPubKey>;
using Type = miniscript::Type;
using MsCtx = miniscript::MiniscriptContext;
using miniscript::operator"" _mst;
//! Some pre-computed data for more efficient string roundtrips and to simulate challenges.
struct TestData {
typedef CPubKey Key;
// Precomputed public keys, and a dummy signature for each of them.
std::vector<Key> dummy_keys;
std::map<Key, int> dummy_key_idx_map;
std::map<CKeyID, Key> dummy_keys_map;
std::map<Key, std::pair<std::vector<unsigned char>, bool>> dummy_sigs;
std::map<XOnlyPubKey, std::pair<std::vector<unsigned char>, bool>> schnorr_sigs;
// Precomputed hashes of each kind.
std::vector<std::vector<unsigned char>> sha256;
std::vector<std::vector<unsigned char>> ripemd160;
std::vector<std::vector<unsigned char>> hash256;
std::vector<std::vector<unsigned char>> hash160;
std::map<std::vector<unsigned char>, std::vector<unsigned char>> sha256_preimages;
std::map<std::vector<unsigned char>, std::vector<unsigned char>> ripemd160_preimages;
std::map<std::vector<unsigned char>, std::vector<unsigned char>> hash256_preimages;
std::map<std::vector<unsigned char>, std::vector<unsigned char>> hash160_preimages;
//! Set the precomputed data.
void Init() {
unsigned char keydata[32] = {1};
// All our signatures sign (and are required to sign) this constant message.
auto const MESSAGE_HASH{uint256S("f5cd94e18b6fe77dd7aca9e35c2b0c9cbd86356c80a71065")};
// We don't pass additional randomness when creating a schnorr signature.
auto const EMPTY_AUX{uint256S("")};
for (size_t i = 0; i < 256; i++) {
keydata[31] = i;
CKey privkey;
privkey.Set(keydata, keydata + 32, true);
const Key pubkey = privkey.GetPubKey();
dummy_keys.push_back(pubkey);
dummy_key_idx_map.emplace(pubkey, i);
dummy_keys_map.insert({pubkey.GetID(), pubkey});
XOnlyPubKey xonly_pubkey{pubkey};
dummy_key_idx_map.emplace(xonly_pubkey, i);
uint160 xonly_hash{Hash160(xonly_pubkey)};
dummy_keys_map.emplace(xonly_hash, pubkey);
std::vector<unsigned char> sig, schnorr_sig(64);
privkey.Sign(MESSAGE_HASH, sig);
sig.push_back(1); // SIGHASH_ALL
dummy_sigs.insert({pubkey, {sig, i & 1}});
assert(privkey.SignSchnorr(MESSAGE_HASH, schnorr_sig, nullptr, EMPTY_AUX));
schnorr_sig.push_back(1); // Maximally-sized signature has sighash byte
schnorr_sigs.emplace(XOnlyPubKey{pubkey}, std::make_pair(std::move(schnorr_sig), i & 1));
std::vector<unsigned char> hash;
hash.resize(32);
CSHA256().Write(keydata, 32).Finalize(hash.data());
sha256.push_back(hash);
if (i & 1) sha256_preimages[hash] = std::vector<unsigned char>(keydata, keydata + 32);
CHash256().Write(keydata).Finalize(hash);
hash256.push_back(hash);
if (i & 1) hash256_preimages[hash] = std::vector<unsigned char>(keydata, keydata + 32);
hash.resize(20);
CRIPEMD160().Write(keydata, 32).Finalize(hash.data());
assert(hash.size() == 20);
ripemd160.push_back(hash);
if (i & 1) ripemd160_preimages[hash] = std::vector<unsigned char>(keydata, keydata + 32);
CHash160().Write(keydata).Finalize(hash);
hash160.push_back(hash);
if (i & 1) hash160_preimages[hash] = std::vector<unsigned char>(keydata, keydata + 32);
}
}
//! Get the (Schnorr or ECDSA, depending on context) signature for this pubkey.
const std::pair<std::vector<unsigned char>, bool>* GetSig(const MsCtx script_ctx, const Key& key) const {
if (!miniscript::IsTapscript(script_ctx)) {
const auto it = dummy_sigs.find(key);
if (it == dummy_sigs.end()) return nullptr;
return &it->second;
} else {
const auto it = schnorr_sigs.find(XOnlyPubKey{key});
if (it == schnorr_sigs.end()) return nullptr;
return &it->second;
}
}
} TEST_DATA;
/**
* Context to parse a Miniscript node to and from Script or text representation.
* Uses an integer (an index in the dummy keys array from the test data) as keys in order
* to focus on fuzzing the Miniscript nodes' test representation, not the key representation.
*/
struct ParserContext {
typedef CPubKey Key;
const MsCtx script_ctx;
constexpr ParserContext(MsCtx ctx) noexcept : script_ctx(ctx) {}
bool KeyCompare(const Key& a, const Key& b) const {
return a < b;
}
std::optional<std::string> ToString(const Key& key) const
{
auto it = TEST_DATA.dummy_key_idx_map.find(key);
if (it == TEST_DATA.dummy_key_idx_map.end()) return {};
uint8_t idx = it->second;
return HexStr(Span{&idx, 1});
}
std::vector<unsigned char> ToPKBytes(const Key& key) const {
if (!miniscript::IsTapscript(script_ctx)) {
return {key.begin(), key.end()};
}
const XOnlyPubKey xonly_pubkey{key};
return {xonly_pubkey.begin(), xonly_pubkey.end()};
}
std::vector<unsigned char> ToPKHBytes(const Key& key) const {
if (!miniscript::IsTapscript(script_ctx)) {
const auto h = Hash160(key);
return {h.begin(), h.end()};
}
const auto h = Hash160(XOnlyPubKey{key});
return {h.begin(), h.end()};
}
template<typename I>
std::optional<Key> FromString(I first, I last) const {
if (last - first != 2) return {};
auto idx = ParseHex(std::string(first, last));
if (idx.size() != 1) return {};
return TEST_DATA.dummy_keys[idx[0]];
}
template<typename I>
std::optional<Key> FromPKBytes(I first, I last) const {
if (!miniscript::IsTapscript(script_ctx)) {
Key key{first, last};
if (key.IsValid()) return key;
return {};
}
if (last - first != 32) return {};
XOnlyPubKey xonly_pubkey;
std::copy(first, last, xonly_pubkey.begin());
return xonly_pubkey.GetEvenCorrespondingCPubKey();
}
template<typename I>
std::optional<Key> FromPKHBytes(I first, I last) const {
assert(last - first == 20);
CKeyID keyid;
std::copy(first, last, keyid.begin());
const auto it = TEST_DATA.dummy_keys_map.find(keyid);
if (it == TEST_DATA.dummy_keys_map.end()) return {};
return it->second;
}
MsCtx MsContext() const {
return script_ctx;
}
};
//! Context that implements naive conversion from/to script only, for roundtrip testing.
struct ScriptParserContext {
const MsCtx script_ctx;
constexpr ScriptParserContext(MsCtx ctx) noexcept : script_ctx(ctx) {}
//! For Script roundtrip we never need the key from a key hash.
struct Key {
bool is_hash;
std::vector<unsigned char> data;
};
bool KeyCompare(const Key& a, const Key& b) const {
return a.data < b.data;
}
const std::vector<unsigned char>& ToPKBytes(const Key& key) const
{
assert(!key.is_hash);
return key.data;
}
std::vector<unsigned char> ToPKHBytes(const Key& key) const
{
if (key.is_hash) return key.data;
const auto h = Hash160(key.data);
return {h.begin(), h.end()};
}
template<typename I>
std::optional<Key> FromPKBytes(I first, I last) const
{
Key key;
key.data.assign(first, last);
key.is_hash = false;
return key;
}
template<typename I>
std::optional<Key> FromPKHBytes(I first, I last) const
{
Key key;
key.data.assign(first, last);
key.is_hash = true;
return key;
}
MsCtx MsContext() const {
return script_ctx;
}
};
//! Context to produce a satisfaction for a Miniscript node using the pre-computed data.
struct SatisfierContext : ParserContext {
constexpr SatisfierContext(MsCtx ctx) noexcept : ParserContext(ctx) {}
// Timelock challenges satisfaction. Make the value (deterministically) vary to explore different
// paths.
bool CheckAfter(uint32_t value) const { return value % 2; }
bool CheckOlder(uint32_t value) const { return value % 2; }
// Signature challenges fulfilled with a dummy signature, if it was one of our dummy keys.
miniscript::Availability Sign(const CPubKey& key, std::vector<unsigned char>& sig) const {
bool sig_available{false};
if (auto res = TEST_DATA.GetSig(script_ctx, key)) {
std::tie(sig, sig_available) = *res;
}
return sig_available ? miniscript::Availability::YES : miniscript::Availability::NO;
}
//! Lookup generalization for all the hash satisfactions below
miniscript::Availability LookupHash(const std::vector<unsigned char>& hash, std::vector<unsigned char>& preimage,
const std::map<std::vector<unsigned char>, std::vector<unsigned char>>& map) const
{
const auto it = map.find(hash);
if (it == map.end()) return miniscript::Availability::NO;
preimage = it->second;
return miniscript::Availability::YES;
}
miniscript::Availability SatSHA256(const std::vector<unsigned char>& hash, std::vector<unsigned char>& preimage) const {
return LookupHash(hash, preimage, TEST_DATA.sha256_preimages);
}
miniscript::Availability SatRIPEMD160(const std::vector<unsigned char>& hash, std::vector<unsigned char>& preimage) const {
return LookupHash(hash, preimage, TEST_DATA.ripemd160_preimages);
}
miniscript::Availability SatHASH256(const std::vector<unsigned char>& hash, std::vector<unsigned char>& preimage) const {
return LookupHash(hash, preimage, TEST_DATA.hash256_preimages);
}
miniscript::Availability SatHASH160(const std::vector<unsigned char>& hash, std::vector<unsigned char>& preimage) const {
return LookupHash(hash, preimage, TEST_DATA.hash160_preimages);
}
};
//! Context to check a satisfaction against the pre-computed data.
const struct CheckerContext: BaseSignatureChecker {
// Signature checker methods. Checks the right dummy signature is used.
bool CheckECDSASignature(const std::vector<unsigned char>& sig, const std::vector<unsigned char>& vchPubKey,
const CScript& scriptCode, SigVersion sigversion) const override
{
const CPubKey key{vchPubKey};
const auto it = TEST_DATA.dummy_sigs.find(key);
if (it == TEST_DATA.dummy_sigs.end()) return false;
return it->second.first == sig;
}
bool CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey, SigVersion,
ScriptExecutionData&, ScriptError*) const override {
XOnlyPubKey pk{pubkey};
auto it = TEST_DATA.schnorr_sigs.find(pk);
if (it == TEST_DATA.schnorr_sigs.end()) return false;
return it->second.first == sig;
}
bool CheckLockTime(const CScriptNum& nLockTime) const override { return nLockTime.GetInt64() & 1; }
bool CheckSequence(const CScriptNum& nSequence) const override { return nSequence.GetInt64() & 1; }
} CHECKER_CTX;
//! Context to check for duplicates when instancing a Node.
const struct KeyComparator {
bool KeyCompare(const CPubKey& a, const CPubKey& b) const {
return a < b;
}
} KEY_COMP;
// A dummy scriptsig to pass to VerifyScript (we always use Segwit v0).
const CScript DUMMY_SCRIPTSIG;
//! Public key to be used as internal key for dummy Taproot spends.
const std::vector<unsigned char> NUMS_PK{ParseHex("50929b74c1a04954b78b4b6035e97a5e078a5a0f28ec96d547bfee9ace803ac0")};
//! Construct a miniscript node as a shared_ptr.
template<typename... Args> NodeRef MakeNodeRef(Args&&... args) {
return miniscript::MakeNodeRef<CPubKey>(miniscript::internal::NoDupCheck{}, std::forward<Args>(args)...);
}
/** Information about a yet to be constructed Miniscript node. */
struct NodeInfo {
//! The type of this node
Fragment fragment;
//! The timelock value for older() and after(), the threshold value for multi() and thresh()
uint32_t k;
//! Keys for this node, if it has some
std::vector<CPubKey> keys;
//! The hash value for this node, if it has one
std::vector<unsigned char> hash;
//! The type requirements for the children of this node.
std::vector<Type> subtypes;
NodeInfo(Fragment frag): fragment(frag), k(0) {}
NodeInfo(Fragment frag, CPubKey key): fragment(frag), k(0), keys({key}) {}
NodeInfo(Fragment frag, uint32_t _k): fragment(frag), k(_k) {}
NodeInfo(Fragment frag, std::vector<unsigned char> h): fragment(frag), k(0), hash(std::move(h)) {}
NodeInfo(std::vector<Type> subt, Fragment frag): fragment(frag), k(0), subtypes(std::move(subt)) {}
NodeInfo(std::vector<Type> subt, Fragment frag, uint32_t _k): fragment(frag), k(_k), subtypes(std::move(subt)) {}
NodeInfo(Fragment frag, uint32_t _k, std::vector<CPubKey> _keys): fragment(frag), k(_k), keys(std::move(_keys)) {}
};
/** Pick an index in a collection from a single byte in the fuzzer's output. */
template<typename T, typename A>
T ConsumeIndex(FuzzedDataProvider& provider, A& col) {
const uint8_t i = provider.ConsumeIntegral<uint8_t>();
return col[i];
}
CPubKey ConsumePubKey(FuzzedDataProvider& provider) {
return ConsumeIndex<CPubKey>(provider, TEST_DATA.dummy_keys);
}
std::vector<unsigned char> ConsumeSha256(FuzzedDataProvider& provider) {
return ConsumeIndex<std::vector<unsigned char>>(provider, TEST_DATA.sha256);
}
std::vector<unsigned char> ConsumeHash256(FuzzedDataProvider& provider) {
return ConsumeIndex<std::vector<unsigned char>>(provider, TEST_DATA.hash256);
}
std::vector<unsigned char> ConsumeRipemd160(FuzzedDataProvider& provider) {
return ConsumeIndex<std::vector<unsigned char>>(provider, TEST_DATA.ripemd160);
}
std::vector<unsigned char> ConsumeHash160(FuzzedDataProvider& provider) {
return ConsumeIndex<std::vector<unsigned char>>(provider, TEST_DATA.hash160);
}
std::optional<uint32_t> ConsumeTimeLock(FuzzedDataProvider& provider) {
const uint32_t k = provider.ConsumeIntegral<uint32_t>();
if (k == 0 || k >= 0x80000000) return {};
return k;
}
/**
* Consume a Miniscript node from the fuzzer's output.
*
* This version is intended to have a fixed, stable, encoding for Miniscript nodes:
* - The first byte sets the type of the fragment. 0, 1 and all non-leaf fragments but thresh() are a
* single byte.
* - For the other leaf fragments, the following bytes depend on their type.
* - For older() and after(), the next 4 bytes define the timelock value.
* - For pk_k(), pk_h(), and all hashes, the next byte defines the index of the value in the test data.
* - For multi(), the next 2 bytes define respectively the threshold and the number of keys. Then as many
* bytes as the number of keys define the index of each key in the test data.
* - For multi_a(), same as for multi() but the threshold and the keys count are encoded on two bytes.
* - For thresh(), the next byte defines the threshold value and the following one the number of subs.
*/
std::optional<NodeInfo> ConsumeNodeStable(MsCtx script_ctx, FuzzedDataProvider& provider, Type type_needed) {
bool allow_B = (type_needed == ""_mst) || (type_needed << "B"_mst);
bool allow_K = (type_needed == ""_mst) || (type_needed << "K"_mst);
bool allow_V = (type_needed == ""_mst) || (type_needed << "V"_mst);
bool allow_W = (type_needed == ""_mst) || (type_needed << "W"_mst);
switch (provider.ConsumeIntegral<uint8_t>()) {
case 0:
if (!allow_B) return {};
return {{Fragment::JUST_0}};
case 1:
if (!allow_B) return {};
return {{Fragment::JUST_1}};
case 2:
if (!allow_K) return {};
return {{Fragment::PK_K, ConsumePubKey(provider)}};
case 3:
if (!allow_K) return {};
return {{Fragment::PK_H, ConsumePubKey(provider)}};
case 4: {
if (!allow_B) return {};
const auto k = ConsumeTimeLock(provider);
if (!k) return {};
return {{Fragment::OLDER, *k}};
}
case 5: {
if (!allow_B) return {};
const auto k = ConsumeTimeLock(provider);
if (!k) return {};
return {{Fragment::AFTER, *k}};
}
case 6:
if (!allow_B) return {};
return {{Fragment::SHA256, ConsumeSha256(provider)}};
case 7:
if (!allow_B) return {};
return {{Fragment::HASH256, ConsumeHash256(provider)}};
case 8:
if (!allow_B) return {};
return {{Fragment::RIPEMD160, ConsumeRipemd160(provider)}};
case 9:
if (!allow_B) return {};
return {{Fragment::HASH160, ConsumeHash160(provider)}};
case 10: {
if (!allow_B || IsTapscript(script_ctx)) return {};
const auto k = provider.ConsumeIntegral<uint8_t>();
const auto n_keys = provider.ConsumeIntegral<uint8_t>();
if (n_keys > 20 || k == 0 || k > n_keys) return {};
std::vector<CPubKey> keys{n_keys};
for (auto& key: keys) key = ConsumePubKey(provider);
return {{Fragment::MULTI, k, std::move(keys)}};
}
case 11:
if (!(allow_B || allow_K || allow_V)) return {};
return {{{"B"_mst, type_needed, type_needed}, Fragment::ANDOR}};
case 12:
if (!(allow_B || allow_K || allow_V)) return {};
return {{{"V"_mst, type_needed}, Fragment::AND_V}};
case 13:
if (!allow_B) return {};
return {{{"B"_mst, "W"_mst}, Fragment::AND_B}};
case 15:
if (!allow_B) return {};
return {{{"B"_mst, "W"_mst}, Fragment::OR_B}};
case 16:
if (!allow_V) return {};
return {{{"B"_mst, "V"_mst}, Fragment::OR_C}};
case 17:
if (!allow_B) return {};
return {{{"B"_mst, "B"_mst}, Fragment::OR_D}};
case 18:
if (!(allow_B || allow_K || allow_V)) return {};
return {{{type_needed, type_needed}, Fragment::OR_I}};
case 19: {
if (!allow_B) return {};
auto k = provider.ConsumeIntegral<uint8_t>();
auto n_subs = provider.ConsumeIntegral<uint8_t>();
if (k == 0 || k > n_subs) return {};
std::vector<Type> subtypes;
subtypes.reserve(n_subs);
subtypes.emplace_back("B"_mst);
for (size_t i = 1; i < n_subs; ++i) subtypes.emplace_back("W"_mst);
return {{std::move(subtypes), Fragment::THRESH, k}};
}
case 20:
if (!allow_W) return {};
return {{{"B"_mst}, Fragment::WRAP_A}};
case 21:
if (!allow_W) return {};
return {{{"B"_mst}, Fragment::WRAP_S}};
case 22:
if (!allow_B) return {};
return {{{"K"_mst}, Fragment::WRAP_C}};
case 23:
if (!allow_B) return {};
return {{{"V"_mst}, Fragment::WRAP_D}};
case 24:
if (!allow_V) return {};
return {{{"B"_mst}, Fragment::WRAP_V}};
case 25:
if (!allow_B) return {};
return {{{"B"_mst}, Fragment::WRAP_J}};
case 26:
if (!allow_B) return {};
return {{{"B"_mst}, Fragment::WRAP_N}};
case 27: {
if (!allow_B || !IsTapscript(script_ctx)) return {};
const auto k = provider.ConsumeIntegral<uint16_t>();
const auto n_keys = provider.ConsumeIntegral<uint16_t>();
if (n_keys > 999 || k == 0 || k > n_keys) return {};
std::vector<CPubKey> keys{n_keys};
for (auto& key: keys) key = ConsumePubKey(provider);
return {{Fragment::MULTI_A, k, std::move(keys)}};
}
default:
break;
}
return {};
}
/* This structure contains a table which for each "target" Type a list of recipes
* to construct it, automatically inferred from the behavior of ComputeType.
* Note that the Types here are not the final types of the constructed Nodes, but
* just the subset that are required. For example, a recipe for the "Bo" type
* might construct a "Bondu" sha256() NodeInfo, but cannot construct a "Bz" older().
* Each recipe is a Fragment together with a list of required types for its subnodes.
*/
struct SmartInfo
{
using recipe = std::pair<Fragment, std::vector<Type>>;
std::map<Type, std::vector<recipe>> wsh_table, tap_table;
void Init()
{
Init(wsh_table, MsCtx::P2WSH);
Init(tap_table, MsCtx::TAPSCRIPT);
}
void Init(std::map<Type, std::vector<recipe>>& table, MsCtx script_ctx)
{
/* Construct a set of interesting type requirements to reason with (sections of BKVWzondu). */
std::vector<Type> types;
for (int base = 0; base < 4; ++base) { /* select from B,K,V,W */
Type type_base = base == 0 ? "B"_mst : base == 1 ? "K"_mst : base == 2 ? "V"_mst : "W"_mst;
for (int zo = 0; zo < 3; ++zo) { /* select from z,o,(none) */
Type type_zo = zo == 0 ? "z"_mst : zo == 1 ? "o"_mst : ""_mst;
for (int n = 0; n < 2; ++n) { /* select from (none),n */
if (zo == 0 && n == 1) continue; /* z conflicts with n */
if (base == 3 && n == 1) continue; /* W conflicts with n */
Type type_n = n == 0 ? ""_mst : "n"_mst;
for (int d = 0; d < 2; ++d) { /* select from (none),d */
if (base == 2 && d == 1) continue; /* V conflicts with d */
Type type_d = d == 0 ? ""_mst : "d"_mst;
for (int u = 0; u < 2; ++u) { /* select from (none),u */
if (base == 2 && u == 1) continue; /* V conflicts with u */
Type type_u = u == 0 ? ""_mst : "u"_mst;
Type type = type_base | type_zo | type_n | type_d | type_u;
types.push_back(type);
}
}
}
}
}
/* We define a recipe a to be a super-recipe of recipe b if they use the same
* fragment, the same number of subexpressions, and each of a's subexpression
* types is a supertype of the corresponding subexpression type of b.
* Within the set of recipes for the construction of a given type requirement,
* no recipe should be a super-recipe of another (as the super-recipe is
* applicable in every place the sub-recipe is, the sub-recipe is redundant). */
auto is_super_of = [](const recipe& a, const recipe& b) {
if (a.first != b.first) return false;
if (a.second.size() != b.second.size()) return false;
for (size_t i = 0; i < a.second.size(); ++i) {
if (!(b.second[i] << a.second[i])) return false;
}
return true;
};
/* Sort the type requirements. Subtypes will always sort later (e.g. Bondu will
* sort after Bo or Bu). As we'll be constructing recipes using these types, in
* order, in what follows, we'll construct super-recipes before sub-recipes.
* That means we never need to go back and delete a sub-recipe because a
* super-recipe got added. */
std::sort(types.begin(), types.end());
// Iterate over all possible fragments.
for (int fragidx = 0; fragidx <= int(Fragment::MULTI_A); ++fragidx) {
int sub_count = 0; //!< The minimum number of child nodes this recipe has.
int sub_range = 1; //!< The maximum number of child nodes for this recipe is sub_count+sub_range-1.
size_t data_size = 0;
size_t n_keys = 0;
uint32_t k = 0;
Fragment frag{fragidx};
// Only produce recipes valid in the given context.
if ((!miniscript::IsTapscript(script_ctx) && frag == Fragment::MULTI_A)
|| (miniscript::IsTapscript(script_ctx) && frag == Fragment::MULTI)) {
continue;
}
// Based on the fragment, determine #subs/data/k/keys to pass to ComputeType. */
switch (frag) {
case Fragment::PK_K:
case Fragment::PK_H:
n_keys = 1;
break;
case Fragment::MULTI:
case Fragment::MULTI_A:
n_keys = 1;
k = 1;
break;
case Fragment::OLDER:
case Fragment::AFTER:
k = 1;
break;
case Fragment::SHA256:
case Fragment::HASH256:
data_size = 32;
break;
case Fragment::RIPEMD160:
case Fragment::HASH160:
data_size = 20;
break;
case Fragment::JUST_0:
case Fragment::JUST_1:
break;
case Fragment::WRAP_A:
case Fragment::WRAP_S:
case Fragment::WRAP_C:
case Fragment::WRAP_D:
case Fragment::WRAP_V:
case Fragment::WRAP_J:
case Fragment::WRAP_N:
sub_count = 1;
break;
case Fragment::AND_V:
case Fragment::AND_B:
case Fragment::OR_B:
case Fragment::OR_C:
case Fragment::OR_D:
case Fragment::OR_I:
sub_count = 2;
break;
case Fragment::ANDOR:
sub_count = 3;
break;
case Fragment::THRESH:
// Thresh logic is executed for 1 and 2 arguments. Larger numbers use ad-hoc code to extend.
sub_count = 1;
sub_range = 2;
k = 1;
break;
}
// Iterate over the number of subnodes (sub_count...sub_count+sub_range-1).
std::vector<Type> subt;
for (int subs = sub_count; subs < sub_count + sub_range; ++subs) {
// Iterate over the possible subnode types (at most 3).
for (Type x : types) {
for (Type y : types) {
for (Type z : types) {
// Compute the resulting type of a node with the selected fragment / subnode types.
subt.clear();
if (subs > 0) subt.push_back(x);
if (subs > 1) subt.push_back(y);
if (subs > 2) subt.push_back(z);
Type res = miniscript::internal::ComputeType(frag, x, y, z, subt, k, data_size, subs, n_keys, script_ctx);
// Continue if the result is not a valid node.
if ((res << "K"_mst) + (res << "V"_mst) + (res << "B"_mst) + (res << "W"_mst) != 1) continue;
recipe entry{frag, subt};
auto super_of_entry = [&](const recipe& rec) { return is_super_of(rec, entry); };
// Iterate over all supertypes of res (because if e.g. our selected fragment/subnodes result
// in a Bondu, they can form a recipe that is also applicable for constructing a B, Bou, Bdu, ...).
for (Type s : types) {
if ((res & "BKVWzondu"_mst) << s) {
auto& recipes = table[s];
// If we don't already have a super-recipe to the new one, add it.
if (!std::any_of(recipes.begin(), recipes.end(), super_of_entry)) {
recipes.push_back(entry);
}
}
}
if (subs <= 2) break;
}
if (subs <= 1) break;
}
if (subs <= 0) break;
}
}
}
/* Find which types are useful. The fuzzer logic only cares about constructing
* B,V,K,W nodes, so any type that isn't needed in any recipe (directly or
* indirectly) for the construction of those is uninteresting. */
std::set<Type> useful_types{"B"_mst, "V"_mst, "K"_mst, "W"_mst};
// Find the transitive closure by adding types until the set of types does not change.
while (true) {
size_t set_size = useful_types.size();
for (const auto& [type, recipes] : table) {
if (useful_types.count(type) != 0) {
for (const auto& [_, subtypes] : recipes) {
for (auto subtype : subtypes) useful_types.insert(subtype);
}
}
}
if (useful_types.size() == set_size) break;
}
// Remove all rules that construct uninteresting types.
for (auto type_it = table.begin(); type_it != table.end();) {
if (useful_types.count(type_it->first) == 0) {
type_it = table.erase(type_it);
} else {
++type_it;
}
}
/* Find which types are constructible. A type is constructible if there is a leaf
* node recipe for constructing it, or a recipe whose subnodes are all constructible.
* Types can be non-constructible because they have no recipes to begin with,
* because they can only be constructed using recipes that involve otherwise
* non-constructible types, or because they require infinite recursion. */
std::set<Type> constructible_types{};
auto known_constructible = [&](Type type) { return constructible_types.count(type) != 0; };
// Find the transitive closure by adding types until the set of types does not change.
while (true) {
size_t set_size = constructible_types.size();
// Iterate over all types we have recipes for.
for (const auto& [type, recipes] : table) {
if (!known_constructible(type)) {
// For not (yet known to be) constructible types, iterate over their recipes.
for (const auto& [_, subt] : recipes) {
// If any recipe involves only (already known to be) constructible types,
// add the recipe's type to the set.
if (std::all_of(subt.begin(), subt.end(), known_constructible)) {
constructible_types.insert(type);
break;
}
}
}
}
if (constructible_types.size() == set_size) break;
}
for (auto type_it = table.begin(); type_it != table.end();) {
// Remove all recipes which involve non-constructible types.
type_it->second.erase(std::remove_if(type_it->second.begin(), type_it->second.end(),
[&](const recipe& rec) {
return !std::all_of(rec.second.begin(), rec.second.end(), known_constructible);
}), type_it->second.end());
// Delete types entirely which have no recipes left.
if (type_it->second.empty()) {
type_it = table.erase(type_it);
} else {
++type_it;
}
}
for (auto& [type, recipes] : table) {
// Sort recipes for determinism, and place those using fewer subnodes first.
// This avoids runaway expansion (when reaching the end of the fuzz input,
// all zeroes are read, resulting in the first available recipe being picked).
std::sort(recipes.begin(), recipes.end(),
[](const recipe& a, const recipe& b) {
if (a.second.size() < b.second.size()) return true;
if (a.second.size() > b.second.size()) return false;
return a < b;
}
);
}
}
} SMARTINFO;
/**
* Consume a Miniscript node from the fuzzer's output.
*
* This is similar to ConsumeNodeStable, but uses a precomputed table with permitted
* fragments/subnode type for each required type. It is intended to more quickly explore
* interesting miniscripts, at the cost of higher implementation complexity (which could
* cause it miss things if incorrect), and with less regard for stability of the seeds
* (as improvements to the tables or changes to the typing rules could invalidate
* everything).
*/
std::optional<NodeInfo> ConsumeNodeSmart(MsCtx script_ctx, FuzzedDataProvider& provider, Type type_needed) {
/** Table entry for the requested type. */
const auto& table{IsTapscript(script_ctx) ? SMARTINFO.tap_table : SMARTINFO.wsh_table};
auto recipes_it = table.find(type_needed);
assert(recipes_it != table.end());
/** Pick one recipe from the available ones for that type. */
const auto& [frag, subt] = PickValue(provider, recipes_it->second);
// Based on the fragment the recipe uses, fill in other data (k, keys, data).
switch (frag) {
case Fragment::PK_K:
case Fragment::PK_H:
return {{frag, ConsumePubKey(provider)}};
case Fragment::MULTI: {
const auto n_keys = provider.ConsumeIntegralInRange<uint8_t>(1, 20);
const auto k = provider.ConsumeIntegralInRange<uint8_t>(1, n_keys);
std::vector<CPubKey> keys{n_keys};
for (auto& key: keys) key = ConsumePubKey(provider);
return {{frag, k, std::move(keys)}};
}
case Fragment::MULTI_A: {
const auto n_keys = provider.ConsumeIntegralInRange<uint16_t>(1, 999);
const auto k = provider.ConsumeIntegralInRange<uint16_t>(1, n_keys);
std::vector<CPubKey> keys{n_keys};
for (auto& key: keys) key = ConsumePubKey(provider);
return {{frag, k, std::move(keys)}};
}
case Fragment::OLDER:
case Fragment::AFTER:
return {{frag, provider.ConsumeIntegralInRange<uint32_t>(1, 0x7FFFFFF)}};
case Fragment::SHA256:
return {{frag, PickValue(provider, TEST_DATA.sha256)}};
case Fragment::HASH256:
return {{frag, PickValue(provider, TEST_DATA.hash256)}};
case Fragment::RIPEMD160:
return {{frag, PickValue(provider, TEST_DATA.ripemd160)}};
case Fragment::HASH160:
return {{frag, PickValue(provider, TEST_DATA.hash160)}};
case Fragment::JUST_0:
case Fragment::JUST_1:
case Fragment::WRAP_A:
case Fragment::WRAP_S:
case Fragment::WRAP_C:
case Fragment::WRAP_D:
case Fragment::WRAP_V:
case Fragment::WRAP_J:
case Fragment::WRAP_N:
case Fragment::AND_V:
case Fragment::AND_B:
case Fragment::OR_B:
case Fragment::OR_C:
case Fragment::OR_D:
case Fragment::OR_I:
case Fragment::ANDOR:
return {{subt, frag}};
case Fragment::THRESH: {
uint32_t children;
if (subt.size() < 2) {
children = subt.size();
} else {
// If we hit a thresh with 2 subnodes, artificially extend it to any number
// (2 or larger) by replicating the type of the last subnode.
children = provider.ConsumeIntegralInRange<uint32_t>(2, MAX_OPS_PER_SCRIPT / 2);
}
auto k = provider.ConsumeIntegralInRange<uint32_t>(1, children);
std::vector<Type> subs = subt;
while (subs.size() < children) subs.push_back(subs.back());
return {{std::move(subs), frag, k}};
}
}
assert(false);
}
/**
* Generate a Miniscript node based on the fuzzer's input.
*
* - ConsumeNode is a function object taking a Type, and returning an std::optional<NodeInfo>.
* - root_type is the required type properties of the constructed NodeRef.
* - strict_valid sets whether ConsumeNode is expected to guarantee a NodeInfo that results in
* a NodeRef whose Type() matches the type fed to ConsumeNode.
*/
template<typename F>
NodeRef GenNode(MsCtx script_ctx, F ConsumeNode, Type root_type, bool strict_valid = false) {
/** A stack of miniscript Nodes being built up. */
std::vector<NodeRef> stack;
/** The queue of instructions. */
std::vector<std::pair<Type, std::optional<NodeInfo>>> todo{{root_type, {}}};
/** Predict the number of (static) script ops. */
uint32_t ops{0};
/** Predict the total script size (every unexplored subnode is counted as one, as every leaf is
* at least one script byte). */
uint32_t scriptsize{1};
while (!todo.empty()) {
// The expected type we have to construct.
auto type_needed = todo.back().first;
if (!todo.back().second) {
// Fragment/children have not been decided yet. Decide them.
auto node_info = ConsumeNode(type_needed);
if (!node_info) return {};
// Update predicted resource limits. Since every leaf Miniscript node is at least one
// byte long, we move one byte from each child to their parent. A similar technique is
// used in the miniscript::internal::Parse function to prevent runaway string parsing.
scriptsize += miniscript::internal::ComputeScriptLen(node_info->fragment, ""_mst, node_info->subtypes.size(), node_info->k, node_info->subtypes.size(),
node_info->keys.size(), script_ctx) - 1;
if (scriptsize > MAX_STANDARD_P2WSH_SCRIPT_SIZE) return {};
switch (node_info->fragment) {
case Fragment::JUST_0:
case Fragment::JUST_1:
break;
case Fragment::PK_K:
break;
case Fragment::PK_H:
ops += 3;
break;
case Fragment::OLDER:
case Fragment::AFTER:
ops += 1;
break;
case Fragment::RIPEMD160:
case Fragment::SHA256:
case Fragment::HASH160:
case Fragment::HASH256:
ops += 4;
break;
case Fragment::ANDOR:
ops += 3;
break;
case Fragment::AND_V:
break;
case Fragment::AND_B:
case Fragment::OR_B:
ops += 1;
break;
case Fragment::OR_C:
ops += 2;
break;
case Fragment::OR_D:
ops += 3;
break;
case Fragment::OR_I:
ops += 3;
break;
case Fragment::THRESH:
ops += node_info->subtypes.size();
break;
case Fragment::MULTI:
ops += 1;
break;
case Fragment::MULTI_A:
ops += node_info->keys.size() + 1;
break;
case Fragment::WRAP_A:
ops += 2;
break;
case Fragment::WRAP_S:
ops += 1;
break;
case Fragment::WRAP_C:
ops += 1;
break;
case Fragment::WRAP_D:
ops += 3;
break;
case Fragment::WRAP_V:
// We don't account for OP_VERIFY here; that will be corrected for when the actual
// node is constructed below.
break;
case Fragment::WRAP_J:
ops += 4;
break;
case Fragment::WRAP_N:
ops += 1;
break;
}
if (ops > MAX_OPS_PER_SCRIPT) return {};
auto subtypes = node_info->subtypes;
todo.back().second = std::move(node_info);
todo.reserve(todo.size() + subtypes.size());
// As elements on the todo stack are processed back to front, construct
// them in reverse order (so that the first subnode is generated first).
for (size_t i = 0; i < subtypes.size(); ++i) {
todo.emplace_back(*(subtypes.rbegin() + i), std::nullopt);
}
} else {
// The back of todo has fragment and number of children decided, and
// those children have been constructed at the back of stack. Pop
// that entry off todo, and use it to construct a new NodeRef on
// stack.
NodeInfo& info = *todo.back().second;
// Gather children from the back of stack.
std::vector<NodeRef> sub;
sub.reserve(info.subtypes.size());
for (size_t i = 0; i < info.subtypes.size(); ++i) {
sub.push_back(std::move(*(stack.end() - info.subtypes.size() + i)));
}
stack.erase(stack.end() - info.subtypes.size(), stack.end());
// Construct new NodeRef.
NodeRef node;
if (info.keys.empty()) {
node = MakeNodeRef(script_ctx, info.fragment, std::move(sub), std::move(info.hash), info.k);
} else {
assert(sub.empty());
assert(info.hash.empty());
node = MakeNodeRef(script_ctx, info.fragment, std::move(info.keys), info.k);
}
// Verify acceptability.
if (!node || (node->GetType() & "KVWB"_mst) == ""_mst) {
assert(!strict_valid);
return {};
}
if (!(type_needed == ""_mst)) {
assert(node->GetType() << type_needed);
}
if (!node->IsValid()) return {};
// Update resource predictions.
if (node->fragment == Fragment::WRAP_V && node->subs[0]->GetType() << "x"_mst) {
ops += 1;
scriptsize += 1;
}
if (!miniscript::IsTapscript(script_ctx) && ops > MAX_OPS_PER_SCRIPT) return {};
if (scriptsize > miniscript::internal::MaxScriptSize(script_ctx)) {
return {};
}
// Move it to the stack.
stack.push_back(std::move(node));
todo.pop_back();
}
}
assert(stack.size() == 1);
assert(stack[0]->GetStaticOps() == ops);
assert(stack[0]->ScriptSize() == scriptsize);
stack[0]->DuplicateKeyCheck(KEY_COMP);
return std::move(stack[0]);
}
//! The spk for this script under the given context. If it's a Taproot output also record the spend data.
CScript ScriptPubKey(MsCtx ctx, const CScript& script, TaprootBuilder& builder)
{
if (!miniscript::IsTapscript(ctx)) return CScript() << OP_0 << WitnessV0ScriptHash(script);
// For Taproot outputs we always use a tree with a single script and a dummy internal key.
builder.Add(0, script, TAPROOT_LEAF_TAPSCRIPT);
builder.Finalize(XOnlyPubKey{NUMS_PK});
return GetScriptForDestination(builder.GetOutput());
}
//! Fill the witness with the data additional to the script satisfaction.
void SatisfactionToWitness(MsCtx ctx, CScriptWitness& witness, const CScript& script, TaprootBuilder& builder) {
// For P2WSH, it's only the witness script.
witness.stack.emplace_back(script.begin(), script.end());
if (!miniscript::IsTapscript(ctx)) return;
// For Tapscript we also need the control block.
witness.stack.push_back(*builder.GetSpendData().scripts.begin()->second.begin());
}
/** Perform various applicable tests on a miniscript Node. */
void TestNode(const MsCtx script_ctx, const NodeRef& node, FuzzedDataProvider& provider)
{
if (!node) return;
// Check that it roundtrips to text representation
const ParserContext parser_ctx{script_ctx};
std::optional<std::string> str{node->ToString(parser_ctx)};
assert(str);
auto parsed = miniscript::FromString(*str, parser_ctx);
assert(parsed);
assert(*parsed == *node);
// Check consistency between script size estimation and real size.
auto script = node->ToScript(parser_ctx);
assert(node->ScriptSize() == script.size());
// Check consistency of "x" property with the script (type K is excluded, because it can end
// with a push of a key, which could match these opcodes).
if (!(node->GetType() << "K"_mst)) {
bool ends_in_verify = !(node->GetType() << "x"_mst);
assert(ends_in_verify == (script.back() == OP_CHECKSIG || script.back() == OP_CHECKMULTISIG || script.back() == OP_EQUAL || script.back() == OP_NUMEQUAL));
}
// The rest of the checks only apply when testing a valid top-level script.
if (!node->IsValidTopLevel()) return;
// Check roundtrip to script
auto decoded = miniscript::FromScript(script, parser_ctx);
assert(decoded);
// Note we can't use *decoded == *node because the miniscript representation may differ, so we check that:
// - The script corresponding to that decoded form matches exactly
// - The type matches exactly
assert(decoded->ToScript(parser_ctx) == script);
assert(decoded->GetType() == node->GetType());
// Optionally pad the script or the witness in order to increase the sensitivity of the tests of
// the resources limits logic.
CScriptWitness witness_mal, witness_nonmal;
if (provider.ConsumeBool()) {
// Under P2WSH, optionally pad the script with OP_NOPs to max op the ops limit of the constructed script.
// This makes the script obviously not actually miniscript-compatible anymore, but the
// signatures constructed in this test don't commit to the script anyway, so the same
// miniscript satisfier will work. This increases the sensitivity of the test to the ops
// counting logic being too low, especially for simple scripts.
// Do this optionally because we're not solely interested in cases where the number of ops is
// maximal.
// Do not pad more than what would cause MAX_STANDARD_P2WSH_SCRIPT_SIZE to be reached, however,
// as that also invalidates scripts.
const auto node_ops{node->GetOps()};
if (!IsTapscript(script_ctx) && node_ops && *node_ops < MAX_OPS_PER_SCRIPT
&& node->ScriptSize() < MAX_STANDARD_P2WSH_SCRIPT_SIZE) {
int add = std::min<int>(
MAX_OPS_PER_SCRIPT - *node_ops,
MAX_STANDARD_P2WSH_SCRIPT_SIZE - node->ScriptSize());
for (int i = 0; i < add; ++i) script.push_back(OP_NOP);
}
// Under Tapscript, optionally pad the stack up to the limit minus the calculated maximum execution stack
// size to assert a Miniscript would never add more elements to the stack during execution than anticipated.
const auto node_exec_ss{node->GetExecStackSize()};
if (miniscript::IsTapscript(script_ctx) && node_exec_ss && *node_exec_ss < MAX_STACK_SIZE) {
unsigned add{(unsigned)MAX_STACK_SIZE - *node_exec_ss};
witness_mal.stack.resize(add);
witness_nonmal.stack.resize(add);
script.reserve(add);
for (unsigned i = 0; i < add; ++i) script.push_back(OP_NIP);
}
}
const SatisfierContext satisfier_ctx{script_ctx};
// Get the ScriptPubKey for this script, filling spend data if it's Taproot.
TaprootBuilder builder;
const CScript script_pubkey{ScriptPubKey(script_ctx, script, builder)};
// Run malleable satisfaction algorithm.
std::vector<std::vector<unsigned char>> stack_mal;
const bool mal_success = node->Satisfy(satisfier_ctx, stack_mal, false) == miniscript::Availability::YES;
// Run non-malleable satisfaction algorithm.
std::vector<std::vector<unsigned char>> stack_nonmal;
const bool nonmal_success = node->Satisfy(satisfier_ctx, stack_nonmal, true) == miniscript::Availability::YES;
if (nonmal_success) {
// Non-malleable satisfactions are bounded by the satisfaction size plus:
// - For P2WSH spends, the witness script
// - For Tapscript spends, both the witness script and the control block
const size_t max_stack_size{*node->GetStackSize() + 1 + miniscript::IsTapscript(script_ctx)};
assert(stack_nonmal.size() <= max_stack_size);
// If a non-malleable satisfaction exists, the malleable one must also exist, and be identical to it.
assert(mal_success);
assert(stack_nonmal == stack_mal);
// Compute witness size (excluding script push, control block, and witness count encoding).
const size_t wit_size = GetSerializeSize(stack_nonmal, PROTOCOL_VERSION) - GetSizeOfCompactSize(stack_nonmal.size());
assert(wit_size <= *node->GetWitnessSize());
// Test non-malleable satisfaction.
witness_nonmal.stack.insert(witness_nonmal.stack.end(), std::make_move_iterator(stack_nonmal.begin()), std::make_move_iterator(stack_nonmal.end()));
SatisfactionToWitness(script_ctx, witness_nonmal, script, builder);
ScriptError serror;
bool res = VerifyScript(DUMMY_SCRIPTSIG, script_pubkey, &witness_nonmal, STANDARD_SCRIPT_VERIFY_FLAGS, CHECKER_CTX, &serror);
// Non-malleable satisfactions are guaranteed to be valid if ValidSatisfactions().
if (node->ValidSatisfactions()) assert(res);
// More detailed: non-malleable satisfactions must be valid, or could fail with ops count error (if CheckOpsLimit failed),
// or with a stack size error (if CheckStackSize check failed).
assert(res ||
(!node->CheckOpsLimit() && serror == ScriptError::SCRIPT_ERR_OP_COUNT) ||
(!node->CheckStackSize() && serror == ScriptError::SCRIPT_ERR_STACK_SIZE));
}
if (mal_success && (!nonmal_success || witness_mal.stack != witness_nonmal.stack)) {
// Test malleable satisfaction only if it's different from the non-malleable one.
witness_mal.stack.insert(witness_mal.stack.end(), std::make_move_iterator(stack_mal.begin()), std::make_move_iterator(stack_mal.end()));
SatisfactionToWitness(script_ctx, witness_mal, script, builder);
ScriptError serror;
bool res = VerifyScript(DUMMY_SCRIPTSIG, script_pubkey, &witness_mal, STANDARD_SCRIPT_VERIFY_FLAGS, CHECKER_CTX, &serror);
// Malleable satisfactions are not guaranteed to be valid under any conditions, but they can only
// fail due to stack or ops limits.
assert(res || serror == ScriptError::SCRIPT_ERR_OP_COUNT || serror == ScriptError::SCRIPT_ERR_STACK_SIZE);
}
if (node->IsSane()) {
// For sane nodes, the two algorithms behave identically.
assert(mal_success == nonmal_success);
}
// Verify that if a node is policy-satisfiable, the malleable satisfaction
// algorithm succeeds. Given that under IsSane() both satisfactions
// are identical, this implies that for such nodes, the non-malleable
// satisfaction will also match the expected policy.
const auto is_key_satisfiable = [script_ctx](const CPubKey& pubkey) -> bool {
auto sig_ptr{TEST_DATA.GetSig(script_ctx, pubkey)};
return sig_ptr != nullptr && sig_ptr->second;
};
bool satisfiable = node->IsSatisfiable([&](const Node& node) -> bool {
switch (node.fragment) {
case Fragment::PK_K:
case Fragment::PK_H:
return is_key_satisfiable(node.keys[0]);
case Fragment::MULTI:
case Fragment::MULTI_A: {
size_t sats = std::count_if(node.keys.begin(), node.keys.end(), [&](const auto& key) {
return size_t(is_key_satisfiable(key));
});
return sats >= node.k;
}
case Fragment::OLDER:
case Fragment::AFTER:
return node.k & 1;
case Fragment::SHA256:
return TEST_DATA.sha256_preimages.count(node.data);
case Fragment::HASH256:
return TEST_DATA.hash256_preimages.count(node.data);
case Fragment::RIPEMD160:
return TEST_DATA.ripemd160_preimages.count(node.data);
case Fragment::HASH160:
return TEST_DATA.hash160_preimages.count(node.data);
default:
assert(false);
}
return false;
});
assert(mal_success == satisfiable);
}
} // namespace
void FuzzInit()
{
ECC_Start();
TEST_DATA.Init();
}
void FuzzInitSmart()
{
FuzzInit();
SMARTINFO.Init();
}
/** Fuzz target that runs TestNode on nodes generated using ConsumeNodeStable. */
FUZZ_TARGET(miniscript_stable, .init = FuzzInit)
{
// Run it under both P2WSH and Tapscript contexts.
for (const auto script_ctx: {MsCtx::P2WSH, MsCtx::TAPSCRIPT}) {
FuzzedDataProvider provider(buffer.data(), buffer.size());
TestNode(script_ctx, GenNode(script_ctx, [&](Type needed_type) {
return ConsumeNodeStable(script_ctx, provider, needed_type);
}, ""_mst), provider);
}
}
/** Fuzz target that runs TestNode on nodes generated using ConsumeNodeSmart. */
FUZZ_TARGET(miniscript_smart, .init = FuzzInitSmart)
{
/** The set of types we aim to construct nodes for. Together they cover all. */
static constexpr std::array<Type, 4> BASE_TYPES{"B"_mst, "V"_mst, "K"_mst, "W"_mst};
FuzzedDataProvider provider(buffer.data(), buffer.size());
const auto script_ctx{(MsCtx)provider.ConsumeBool()};
TestNode(script_ctx, GenNode(script_ctx, [&](Type needed_type) {
return ConsumeNodeSmart(script_ctx, provider, needed_type);
}, PickValue(provider, BASE_TYPES), true), provider);
}
/* Fuzz tests that test parsing from a string, and roundtripping via string. */
FUZZ_TARGET(miniscript_string, .init = FuzzInit)
{
if (buffer.empty()) return;
FuzzedDataProvider provider(buffer.data(), buffer.size());
auto str = provider.ConsumeBytesAsString(provider.remaining_bytes() - 1);
const ParserContext parser_ctx{(MsCtx)provider.ConsumeBool()};
auto parsed = miniscript::FromString(str, parser_ctx);
if (!parsed) return;
const auto str2 = parsed->ToString(parser_ctx);
assert(str2);
auto parsed2 = miniscript::FromString(*str2, parser_ctx);
assert(parsed2);
assert(*parsed == *parsed2);
}
/* Fuzz tests that test parsing from a script, and roundtripping via script. */
FUZZ_TARGET(miniscript_script)
{
FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
const std::optional<CScript> script = ConsumeDeserializable<CScript>(fuzzed_data_provider);
if (!script) return;
const ScriptParserContext script_parser_ctx{(MsCtx)fuzzed_data_provider.ConsumeBool()};
const auto ms = miniscript::FromScript(*script, script_parser_ctx);
if (!ms) return;
assert(ms->ToScript(script_parser_ctx) == *script);
}
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