kdmukai

Airgapped NIP-26 Nostr key delegation via SeedSigner

Keep your main identity key safely offline while authorizing a different key to sign on your behalf.

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Demo of Keith's experimental Nostr integration.

Other posts:

• Generate a new airgapped Nostr key via SeedSigner

kdmukai

Airgapped Nostr event signing via SeedSigner

Sign any Nostr event without ever having your key "hot" in a Nostr client app, web browser, or browser extension.

---

Demo of Keith's experimental Nostr integration.

Other posts:

• Generate a new airgapped Nostr key via SeedSigner
• Airgapped Nostr event signing via SeedSigner

kdmukai

Generate a new airgapped Nostr key via SeedSigner

Create a new key with your own entropy, save it as a standard bitcoin BIP-39 mnemonic phrase and/or SeedQR, then export for use in Nostr.

---

Demo of Keith's experimental Nostr integration.

Other posts:

• Generate a new airgapped Nostr key via SeedSigner

kdmukai

"""
see: https://github.com/nostr-protocol/nips/blob/master/26.md
"""
import hashlib

from binascii import unhexlify

from embit import bip39
from embit.bip32 import HDKey
from embit.ec import PrivateKey

kdmukai

        # check if we can list zero value tx as available coins
        # 1. create raw_tx
        # 2. hex-changed one output to 0.0
        # 3. sign and send
        # 4. check if recipient (node0) can list the zero value tx
        usp = self.nodes[1].listunspent(query_options={'minimumAmount': '49.998'})[0]
        inputs = [{"txid": usp['txid'], "vout": usp['vout']}]
        test_amount = Decimal("0.00001000")  # this output amount will be zeroed and thereby added to the fee
        fee = Decimal("0.00000400")  # start with a modest fee so our final fee won't exceed default maxfeerate
        outputs = {self.nodes[1].getnewaddress(): usp['amount'] - test_amount - fee, self.nodes[0].getnewaddress(): test_amount}

kdmukai

from embit import bip32, bip39, script
from embit.slip39 import secure_randint
from embit.wordlists.bip39 import WORDLIST

for i in range(0, 100):
    mnemonic = []
    for j in range(0, 11):
        # note: `secure_randint` is inclusive of the end of the range
        mnemonic.append(WORDLIST[secure_randint(0, 2047)])
    mnemonic.append(WORDLIST[0])

kdmukai

"""
  dependency: pip install embit
"""
from embit import compact
from embit.psbt import PSBT, OutputScope
from embit.script import Script

class OPCODES:
    OP_RETURN = 106
    OP_PUSHDATA1 = 76

kdmukai

import os
from embit import bip39
from embit.wordlists.bip39 import WORDLIST
from seedsigner.models.decode_qr import DecodeQR
from seedsigner.models.encode_qr import EncodeQR
from seedsigner.models.qr_type import QRType
from seedsigner.helpers.qr import QR

seed_bytes = b''

kdmukai

import sys
if sys.platform == 'esp32':
    import machine
    if machine.freq() != 240_000_000:
        machine.freq(240_000_000)  # 240MHz
        print("Set CPU frequency to 240MHz")

import time
import secp256k1
from embit import bip39, bip32

kdmukai

Single sig change-stealing attack from a compromised coordinator

See the full video walkthrough on twitter.

The CORRECT psbt

Spending uxto from regtest: 3641312fc3e418804f1a0a88098b6bf8e3bdca13afd2f0633ca3166fc8533f17

Signing mnemonic: "smoke chimney announce candy glory tongue refuse fatigue cricket once consider beef treat urge wing deny gym robot tobacco adult problem priority wheat diagram"