I was wondering if I can add dummy data into a coinbase transaction’s inputs. Is it possible to do this? Can you insert invalid input scripts into a coinbase transaction? Can you add multiple inputs scripts into a coinbase, do they all have to be legit scripts, if they do open inputs does the coinbase transaction send more than the regular block reward?
Coinbase transactions must:
- Have exactly 1 input.
- That input must have prevout hash 0000...0000, and index 0xFFFFFFFF (an output which isn't actually spent).
- The input's scriptSig must be between 2 and 100 bytes long.
- Post BIP34 (2012), the scriptSig must start with a push of the block height in little endian encoding.
- Be the first transaction in a block.
If it doesn't satisfy all these rules, the transaction, and the block it is in, are invalid.
thanks!, are you super sure about this? why are we adding block height? Feb 11 at 22:11
5Yes, see the BIP34 document itself for a brief rationale: github.com/bitcoin/bips/blob/master/bip-0034.mediawiki; it was a more complete solution for a problem originally addressed by BIP30: github.com/bitcoin/bips/blob/master/bip-0030.mediawiki (which I'm the author of). Feb 11 at 22:35