py-blink_mojo-secure

Chialisp money privacy tool using aggregated Boneh-Lynn-Shacham (BLS) signatures for security. It is based on a python3 driver for automatation.

• Runs on testnet10 by default.
• Requires full node.
• Requires updating anonymous wallet and known wallet to your personal addresses. Can be edited into blink_mojo.py file or set at the prompt, as in: anon_wallet = "txch<whateverwalletaddressyoudesire>"

Install

Clone repository, go into it, make and activate a virtualenv, and then install requirements.

$ git clone https://github.com/geraldneale/py-blink_mojo-secure.git
$ cd py-blink_mojo-secure
$ python3 -m venv venv
$ . ./venv/bin/activate
$ pip3 install -r requirements.txt

Edit the file blink_mojo.py

anon_wallet = "txch<whateverwalletaddressyoudesire>"
   
known_wallet = "txch<whateverotherwalletaddressyoudesire>"
   
value_amount = whatevervalueyoudesire

Run

Start the program in interactive mode and set the wallet variables to your own.

$ python3 -i blink_mojo.py

Use

Follow the prompts to deploy and send the coins from whatever wallet is synced to the Chia blockchain.

Final command

The final command will run automatically and spend all four of the coins you put on the blockchain up to now. If it does not run you can always copy and paste the following to make it run again.

>> blink_mojo(faucet_coin,needs_privacy_coin,decoy_coin,decoy_value_coin)

You should see

"status": "SUCCESS", "success": true

Conclusion

Using this technique one can direct the equivalent value of the needs_privacy_coin intentionally to an anonymous wallet with only the lineage of a public faucet. It is intended to leave the auditor, including the user of blink_mojo, without certainty if the mojos that were once in the needs_privacy_coin ended up in anon_wallet or known_wallet. I encourage you to run this on testnet and challenge my assertion by submitting an issue here for public discourse. If it fails there is a log file which will help you diagnose the problem and possibly recreate a successful spend by hand.

Chia-blockchain offers major privacy opportunities in three forms in this authour's opinion; which are:

1. In Chialisp everything is evaluated in the instant of block formation. Therefore value is moved aribitrarily around a spend bundle to CREATE_COIN outputs in need of value. If there is more than one CREATE_COIN with deficit value and more than one source of excess value in a spend bundle then it introduces doubt as to the source->destination of value transfer. This is what I call the "blink" in blink_mojo.
2. Due to the magic of BLS aggregated signatures there is no certainty on the blockchain of which coins went into which spend bundle in retrospect. There is just one aggregated signature per block. That signature canNOT be reverse engineered to any single spend bundle's aggregated signature with reliability(NOTE: this is as far as I know. please feel free to disagree, but tell me why). The same feature is used within the blink_mojo spend bundle securing each coin with its own BLS key pair and aggregating the signatures at the end securing the coins in the spend bundle from a subtraction attack, but each of the four public keys in the puzzle_reveals look unassociated in retrospect.
3. The puzzle hash for chia smart coins represents arbitrary logic(CREATE_COIN etc). If we request a faucet to send value to a smart coin puzzle hash address, instead of our own wallet, then we effectively control Chia blockchain logic anonymously using a public resource.

Please try it with testnet only. Use in mainnet only at your own risk.

Known issues and todos

1. Todo: The first guided step needs to be broken into two paths a. generating an address and using a faucet to do the spend or b. having blink_mojo do everything under the presumption that a faucet sent to a burner wallet fingerprint that will be used just this once. Right now it's only "b".
2. Todo: Expand the faucet coin functionality to Offer completed txs. In other words, either file a CHIP or hack Chia Offer spec to pay XCH to an aribitrary address. Right now it only pays to the wallet address that makes or takes the offer. This way the parent lineage of the offer maker/taker can be commandeered an appeneded to the needs_privacy value without depending on public faucets which are historically spotty in their uptime.
3. Issue: The anon_wallet address should be curried into the faucet coin puzzle hash, not part of the solution, to maximize that faucet coin's unmalleable control of the spend bundle at the end.
4. Issue: Incompatible with standalone wallet.

Also check out

https://github.com/geraldneale/blink_mojo - the original proof of concept with a nice illustration of the asic concept and easily repoducible, auditable examples.

Twitter @geraldneale

http://mojopuzzler.org - chialisp resources for the capable beginner.

Discord Mojo Puzzler - https://discord.gg/SMFHEE2Z

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