Does any proven third party code exist for this?


To be more specific, what I haven't been able to find out is how to get the sender's bitcoin address when receiving a transaction. As far as I know, bitcoind doesn't have a command that shows the prev_out hash.

3 Answers 3


It is now possible to determine the list of addresses that sent a transaction using the raw transaction JSON-RPC API calls that were released with bitcoind and bitcoin-qt version 0.7. The pseudo-code to accomplish this is:

txid = <relevant transaction id>
addresses = []
raw_tx = decoderawtransaction(getrawtransaction(txid))
for(input in raw_tx['vin']) {
  input_raw_tx = decoderawtransaction(getrawtransaction(input['txid']))

Once you have the list of sending addresses stored in the addresses array, you can compare these addresses to a list of pre-approved green addresses. In most cases, you should expect there to only be a single unique address in the addresses array.

In order to get a list of suitable green addresses, you could hard-code it into your application, or you could use a dynamic source, such as Deepbit's JSON feed. This feed however, is notably missing Mt. Gox's Green Address


As of right now there's only two green addresses, MtGox and Instawallet. A simple string comparison would suffice. In the near future a dictionary would be the way to go and after that there'll most likely be a service that offers a "green address check".

TL;DR: Code is trivial right now. Proven code will come when it's needed but will also be fairly trivial.


Deepbit provides provides a JSON page with a list of popular green addresses:


Index that, then as lodewijk suggested string matching should suffice.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.