script/sign: signing support for Miniscript with timelocks

Author: darosior

src/script/sign.cpp

@@ -438,9 +438,9 @@ struct Satisfier {
     }
 
     //! Time lock satisfactions.
-    // TODO
-    bool CheckAfter(uint32_t value) const { return false; }
-    bool CheckOlder(uint32_t value) const { return false; }
+    bool CheckAfter(uint32_t value) const { return m_creator.Checker().CheckLockTime(CScriptNum(value)); }
+    bool CheckOlder(uint32_t value) const { return m_creator.Checker().CheckSequence(CScriptNum(value)); }
+
 
     //! Hash preimage satisfactions.
     // TODO
@@ -675,6 +675,8 @@ class DummySignatureChecker final : public BaseSignatureChecker
     DummySignatureChecker() = default;
     bool CheckECDSASignature(const std::vector<unsigned char>& sig, const std::vector<unsigned char>& vchPubKey, const CScript& scriptCode, SigVersion sigversion) const override { return sig.size() != 0; }
     bool CheckSchnorrSignature(Span<const unsigned char> sig, Span<const unsigned char> pubkey, SigVersion sigversion, ScriptExecutionData& execdata, ScriptError* serror) const override { return sig.size() != 0; }
+    bool CheckLockTime(const CScriptNum& nLockTime) const override { return true; }
+    bool CheckSequence(const CScriptNum& nSequence) const override { return true; }
 };
 }
 

src/test/descriptor_tests.cpp

@@ -45,6 +45,7 @@ constexpr int DERIVE_HARDENED = 16; // The final derivation is hardened, i.e. en
 constexpr int MIXED_PUBKEYS = 32;
 constexpr int XONLY_KEYS = 64; // X-only pubkeys are in use (and thus inferring/caching may swap parity of pubkeys/keyids)
 constexpr int MISSING_PRIVKEYS = 128; // Not all private keys are available, so ToPrivateString will fail.
+constexpr int SIGNABLE_FAILS = 256; // We can sign with this descriptor, but actually trying to sign will fail
 
 /** Compare two descriptors. If only one of them has a checksum, the checksum is ignored. */
 bool EqualDescriptor(std::string a, std::string b)
@@ -126,8 +127,10 @@ std::set<std::pair<CPubKey, KeyOriginInfo>> GetKeyOriginData(const FlatSigningPr
     return ret;
 }
 
-void DoCheck(const std::string& prv, const std::string& pub, const std::string& norm_pub, int flags, const std::vector<std::vector<std::string>>& scripts, const std::optional<OutputType>& type, const std::set<std::vector<uint32_t>>& paths = ONLY_EMPTY,
-    bool replace_apostrophe_with_h_in_prv=false, bool replace_apostrophe_with_h_in_pub=false)
+void DoCheck(const std::string& prv, const std::string& pub, const std::string& norm_pub, int flags,
+             const std::vector<std::vector<std::string>>& scripts, const std::optional<OutputType>& type,
+             const std::set<std::vector<uint32_t>>& paths = ONLY_EMPTY, bool replace_apostrophe_with_h_in_prv=false,
+             bool replace_apostrophe_with_h_in_pub=false, uint32_t spender_nlocktime=0, uint32_t spender_nsequence=CTxIn::SEQUENCE_FINAL)
 {
     FlatSigningProvider keys_priv, keys_pub;
     std::set<std::vector<uint32_t>> left_paths = paths;
@@ -303,16 +306,19 @@ void DoCheck(const std::string& prv, const std::string& pub, const std::string&
             for (size_t n = 0; n < spks.size(); ++n) {
                 BOOST_CHECK_EQUAL(ref[n], HexStr(spks[n]));
 
-                if (flags & SIGNABLE) {
+                if (flags & (SIGNABLE | SIGNABLE_FAILS)) {
                     CMutableTransaction spend;
+                    spend.nLockTime = spender_nlocktime;
                     spend.vin.resize(1);
+                    spend.vin[0].nSequence = spender_nsequence;
                     spend.vout.resize(1);
                     std::vector<CTxOut> utxos(1);
                     PrecomputedTransactionData txdata;
                     txdata.Init(spend, std::move(utxos), /*force=*/true);
                     MutableTransactionSignatureCreator creator{spend, 0, CAmount{0}, &txdata, SIGHASH_DEFAULT};
                     SignatureData sigdata;
-                    BOOST_CHECK_MESSAGE(ProduceSignature(FlatSigningProvider{keys_priv}.Merge(FlatSigningProvider{script_provider}), creator, spks[n], sigdata), prv);
+                    const auto prod_sig_res = ProduceSignature(FlatSigningProvider{keys_priv}.Merge(FlatSigningProvider{script_provider}), creator, spks[n], sigdata);
+                    BOOST_CHECK_MESSAGE(prod_sig_res == !(flags & SIGNABLE_FAILS), prv);
                 }
 
                 /* Infer a descriptor from the generated script, and verify its solvability and that it roundtrips. */
@@ -340,29 +346,40 @@ void DoCheck(const std::string& prv, const std::string& pub, const std::string&
     BOOST_CHECK_MESSAGE(left_paths.empty(), "Not all expected key paths found: " + prv);
 }
 
-void Check(const std::string& prv, const std::string& pub, const std::string& norm_pub, int flags, const std::vector<std::vector<std::string>>& scripts, const std::optional<OutputType>& type, const std::set<std::vector<uint32_t>>& paths = ONLY_EMPTY)
+void Check(const std::string& prv, const std::string& pub, const std::string& norm_pub, int flags,
+           const std::vector<std::vector<std::string>>& scripts, const std::optional<OutputType>& type,
+           const std::set<std::vector<uint32_t>>& paths = ONLY_EMPTY, uint32_t spender_nlocktime=0,
+           uint32_t spender_nsequence=CTxIn::SEQUENCE_FINAL)
 {
     bool found_apostrophes_in_prv = false;
     bool found_apostrophes_in_pub = false;
 
     // Do not replace apostrophes with 'h' in prv and pub
-    DoCheck(prv, pub, norm_pub, flags, scripts, type, paths);
+    DoCheck(prv, pub, norm_pub, flags, scripts, type, paths, /*replace_apostrophe_with_h_in_prv=*/false,
+            /*replace_apostrophe_with_h_in_pub=*/false, /*spender_nlocktime=*/spender_nlocktime,
+            /*spender_nsequence=*/spender_nsequence);
 
     // Replace apostrophes with 'h' in prv but not in pub, if apostrophes are found in prv
     if (prv.find('\'') != std::string::npos) {
         found_apostrophes_in_prv = true;
-        DoCheck(prv, pub, norm_pub, flags, scripts, type, paths, /* replace_apostrophe_with_h_in_prv = */true, /*replace_apostrophe_with_h_in_pub = */false);
+        DoCheck(prv, pub, norm_pub, flags, scripts, type, paths, /*replace_apostrophe_with_h_in_prv=*/true,
+                /*replace_apostrophe_with_h_in_pub=*/false, /*spender_nlocktime=*/spender_nlocktime,
+                /*spender_nsequence=*/spender_nsequence);
     }
 
     // Replace apostrophes with 'h' in pub but not in prv, if apostrophes are found in pub
     if (pub.find('\'') != std::string::npos) {
         found_apostrophes_in_pub = true;
-        DoCheck(prv, pub, norm_pub, flags, scripts, type, paths, /* replace_apostrophe_with_h_in_prv = */false, /*replace_apostrophe_with_h_in_pub = */true);
+        DoCheck(prv, pub, norm_pub, flags, scripts, type, paths, /*replace_apostrophe_with_h_in_prv=*/false,
+                /*replace_apostrophe_with_h_in_pub=*/true,  /*spender_nlocktime=*/spender_nlocktime,
+                /*spender_nsequence=*/spender_nsequence);
     }
 
     // Replace apostrophes with 'h' both in prv and in pub, if apostrophes are found in both
     if (found_apostrophes_in_prv && found_apostrophes_in_pub) {
-        DoCheck(prv, pub, norm_pub, flags, scripts, type, paths, /* replace_apostrophe_with_h_in_prv = */true, /*replace_apostrophe_with_h_in_pub = */true);
+        DoCheck(prv, pub, norm_pub, flags, scripts, type, paths, /*replace_apostrophe_with_h_in_prv=*/true,
+                /*replace_apostrophe_with_h_in_pub=*/true, /*spender_nlocktime=*/spender_nlocktime,
+                /*spender_nsequence=*/spender_nsequence);
     }
 }
 
@@ -529,11 +546,17 @@ BOOST_AUTO_TEST_CASE(descriptor_test)
     CheckUnparsable("wsh(and_b(or_b(pkh(L4gM1FBdyHNpkzsFh9ipnofLhpZRp2mwobpeULy1a6dBTvw8Ywtd),s:pk(Kx9HCDjGiwFcgVNhTrS5z5NeZdD6veeam61eDxLDCkGWujvL4Gnn)),s:pk(L4gM1FBdyHNpkzsFh9ipnofLhpZRp2mwobpeULy1a6dBTvw8Ywtd)))", "wsh(and_b(or_b(pkh(03cdabb7f2dce7bfbd8a0b9570c6fd1e712e5d64045e9d6b517b3d5072251dc204),s:pk(032707170c71d8f75e4ca4e3fce870b9409dcaf12b051d3bcadff74747fa7619c0)),s:pk(03cdabb7f2dce7bfbd8a0b9570c6fd1e712e5d64045e9d6b517b3d5072251dc204)))", "and_b(or_b(pkh(03cdabb7f2dce7bfbd8a0b9570c6fd1e712e5d64045e9d6b517b3d5072251dc204),s:pk(032707170c71d8f75e4ca4e3fce870b9409dcaf12b051d3bcadff74747fa7619c0)),s:pk(03cdabb7f2dce7bfbd8a0b9570c6fd1e712e5d64045e9d6b517b3d5072251dc204)) is not sane: contains duplicate public keys");
     // Valid with extended keys.
     Check("wsh(and_v(v:ripemd160(095ff41131e5946f3c85f79e44adbcf8e27e080e),multi(1,xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc,xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L/0)))", "wsh(and_v(v:ripemd160(095ff41131e5946f3c85f79e44adbcf8e27e080e),multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0)))", "wsh(and_v(v:ripemd160(095ff41131e5946f3c85f79e44adbcf8e27e080e),multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0)))", DEFAULT, {{"0020acf425291b98a1d7e0d4690139442abc289175be32ef1f75945e339924246d73"}}, OutputType::BECH32, {{},{0}});
-    // Valid under sh(wsh()) and with a mix of xpubs and raw keys. Note how we can only satisfy a single
-    // branch (timelock sat isn't implemented yet) but we can solve and sign the script nonetheless.
+    // Valid under sh(wsh()) and with a mix of xpubs and raw keys.
     Check("sh(wsh(thresh(1,pkh(L4gM1FBdyHNpkzsFh9ipnofLhpZRp2mwobpeULy1a6dBTvw8Ywtd),a:and_n(multi(1,xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc,xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L/0),n:older(2)))))", "sh(wsh(thresh(1,pkh(03cdabb7f2dce7bfbd8a0b9570c6fd1e712e5d64045e9d6b517b3d5072251dc204),a:and_n(multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0),n:older(2)))))", "sh(wsh(thresh(1,pkh(03cdabb7f2dce7bfbd8a0b9570c6fd1e712e5d64045e9d6b517b3d5072251dc204),a:and_n(multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0),n:older(2)))))", SIGNABLE | MIXED_PUBKEYS, {{"a914767e9119ff3b3ac0cb6dcfe21de1842ccf85f1c487"}}, OutputType::P2SH_SEGWIT, {{},{0}});
     // An exotic multisig, we can sign for both branches
     Check("wsh(thresh(1,pk(xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc),a:pkh(xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L/0)))", "wsh(thresh(1,pk(xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL),a:pkh(xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0)))", "wsh(thresh(1,pk(xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL),a:pkh(xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0)))", SIGNABLE, {{"00204a4528fbc0947e02e921b54bd476fc8cc2ebb5c6ae2ccf10ed29fe2937fb6892"}}, OutputType::BECH32, {{},{0}});
+    // We can sign for a script requiring the two kinds of timelock.
+    // But if we don't set a sequence high enough, we'll fail.
+    Check("sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc,xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L/0),n:older(2)))))", "sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0),n:older(2)))))", "sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0),n:older(2)))))", SIGNABLE_FAILS, {{"a914099f400961f930d4c16c3b33c0e2a58ef53ac38f87"}}, OutputType::P2SH_SEGWIT, {{},{0}}, /*spender_nlocktime=*/1000, /*spender_nsequence=*/1);
+    // And same for the nLockTime.
+    Check("sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc,xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L/0),n:older(2)))))", "sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0),n:older(2)))))", "sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0),n:older(2)))))", SIGNABLE_FAILS, {{"a914099f400961f930d4c16c3b33c0e2a58ef53ac38f87"}}, OutputType::P2SH_SEGWIT, {{},{0}}, /*spender_nlocktime=*/999, /*spender_nsequence=*/2);
+    // But if both are set to (at least) the required value, we'll succeed.
+    Check("sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xprvA1RpRA33e1JQ7ifknakTFpgNXPmW2YvmhqLQYMmrj4xJXXWYpDPS3xz7iAxn8L39njGVyuoseXzU6rcxFLJ8HFsTjSyQbLYnMpCqE2VbFWc,xprv9uPDJpEQgRQfDcW7BkF7eTya6RPxXeJCqCJGHuCJ4GiRVLzkTXBAJMu2qaMWPrS7AANYqdq6vcBcBUdJCVVFceUvJFjaPdGZ2y9WACViL4L/0),n:older(2)))))", "sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0),n:older(2)))))", "sh(wsh(thresh(2,ndv:after(1000),a:and_n(multi(1,xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL,xpub68NZiKmJWnxxS6aaHmn81bvJeTESw724CRDs6HbuccFQN9Ku14VQrADWgqbhhTHBaohPX4CjNLf9fq9MYo6oDaPPLPxSb7gwQN3ih19Zm4Y/0),n:older(2)))))", SIGNABLE, {{"a914099f400961f930d4c16c3b33c0e2a58ef53ac38f87"}}, OutputType::P2SH_SEGWIT, {{},{0}}, /*spender_nlocktime=*/1000, /*spender_nsequence=*/2);
 }
 
 BOOST_AUTO_TEST_SUITE_END()