From 0c8ea6380c9f402ed9777fd015b117ba13125a35 Mon Sep 17 00:00:00 2001 From: Pieter Wuille Date: Thu, 30 Nov 2017 16:48:31 -0800 Subject: Abstract out IsSolvable from Witnessifier --- src/script/sign.cpp | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'src/script/sign.cpp') diff --git a/src/script/sign.cpp b/src/script/sign.cpp index 117a4d8a52..49099bf7b0 100644 --- a/src/script/sign.cpp +++ b/src/script/sign.cpp @@ -422,3 +422,22 @@ bool DummySignatureCreator::CreateSig(std::vector& vchSig, const vchSig[6 + 33 + 32] = SIGHASH_ALL; return true; } + +bool IsSolvable(const CKeyStore& store, const CScript& script) +{ + // This check is to make sure that the script we created can actually be solved for and signed by us + // if we were to have the private keys. This is just to make sure that the script is valid and that, + // if found in a transaction, we would still accept and relay that transaction. In particular, + // it will reject witness outputs that require signing with an uncompressed public key. + DummySignatureCreator creator(&store); + SignatureData sigs; + // Make sure that STANDARD_SCRIPT_VERIFY_FLAGS includes SCRIPT_VERIFY_WITNESS_PUBKEYTYPE, the most + // important property this function is designed to test for. + static_assert(STANDARD_SCRIPT_VERIFY_FLAGS & SCRIPT_VERIFY_WITNESS_PUBKEYTYPE, "IsSolvable requires standard script flags to include WITNESS_PUBKEYTYPE"); + if (ProduceSignature(creator, script, sigs)) { + // VerifyScript check is just defensive, and should never fail. + assert(VerifyScript(sigs.scriptSig, script, &sigs.scriptWitness, STANDARD_SCRIPT_VERIFY_FLAGS, creator.Checker())); + return true; + } + return false; +} -- cgit v1.2.3