Transactions not validating

[bitspill]

When validating transactions the stack evaluates to false on every transaction.

https://github.com/bitspill/slr-bitcoin/blob/wip/src/main.cpp#L1892
https://github.com/bitspill/slr-bitcoin/blob/wip/src/script/interpreter.cpp#L1264

[Dommsko]

Hey, I did not dive fully into the code yet, simply because it's too huge for me and the mechanics are not 100% clear to me, but I will try to give some inspiration for bugfixing nevertheless, because I know that sometimes you don't see possible errors in your own code.

https://github.com/bitspill/slr-bitcoin/blob/wip/src/script/interpreter.cpp#L1263-L1266
https://github.com/bitspill/slr-bitcoin/blob/wip/src/script/interpreter.cpp#L1292-L1293

Looks like one of the if-statements will always trigger if https://github.com/bitspill/slr-bitcoin/blob/wip/src/script/interpreter.cpp#L1269 is True so maybe this has been the case in your testing cases or maybe an exclamation mark in one of the lines is wrong/missing.

[bitspill]

Hey @Dommsko,

Thanks for taking a look but !CastToBool(..) is functionally equivalent to CastToBool(...) == false in addition those are direct from Bitcoin Core rather than a function I've written other than the addition of the std::cout lines to see which one was actually failing.

https://github.com/bitcoin/bitcoin/blob/0.12/src/script/interpreter.cpp#L1259-L1290

[Dommsko]

Sorry, I didn't see that the second check doesn't have "== false" in it. I don't even understand where stack gets its content since it looks to me like it was just defined, but then again it should trigger the .empty() if-clause... well, I don't want to distract you too much with my basic blockchain core knowledge but maybe it helps if you explain to me how it is supposed to work. Anyways, hope you can find the mistake soon!

[bitspill]

The stack is populated within the EvalScript function at https://github.com/bitspill/slr-bitcoin/blob/wip/src/script/interpreter.cpp#L232 a script is described at https://en.bitcoin.it/wiki/Script

The ScriptPubKey is included with a transactions laying out a contract specifying who is allowed to spend the coins being sent, a ScriptSig is then the "password" that passes the ScriptPubKey contracts and allows a user to spend the coins. While there are some "smart contracts" or puzzles out there in Bitcoin most all transactions, especially in Solarcoin, will be of the standard pay-to-pubkey-hash (Sending coins to a BTC/SLR address) which is described at https://en.bitcoin.it/wiki/Script#Standard_Transaction_to_Bitcoin_address_.28pay-to-pubkey-hash.29 -- Basically by the stack evaluating to false it is saying that the spender doesn't have permission to spend those coins -- and in this situation that's an issue because we know they should be able to otherwise they couldn't have spent it (remember we're validating history here, these coins already moved around, rather than checking incoming transactions of unknown validity) What that seems to suggest is that either OP_EQUALVERIFY or OP_CHECKSIG which worked on previous versions are in some way being called incorrectly now