Uses Embit and qrcode modules to generate ascii compact seed QR codes from nostr keys.

nostr_c_seed_qr.py

"""Uses Embit and qrcode modules to convert hex and bech32 keys to BIP39 seed words and vice-versa.
Also generates ascii compact seed QR codes and public keys.

Install Embit:
pip install embit

Exemple: Words as input:
python nostr_c_seed_qr.py picture body actor coil end satoshi fish mom distance proof thank play fantasy friend dinner clump boring ozone review cart virtual toss foot infant

Exemple: Hex key as input:
python nostr_c_seed_qr.py a4431c0a96a4997ed5ec763fb58b7f532530b9cf916219f3d2e2118f47cb56bb

Exemple: Bech32 key as input:
python nostr_c_seed_qr.py nsec153p3cz5k5jvha40vwclmtzml2vjnpww0j93pnu7juggc737t26ascxcmgr
"""

import sys
from io import StringIO
from embit import bip39, bech32, ec
from embit.wordlists.bip39 import WORDLIST
from qrcode import QRCode

def _compact_seed_qr():
    # Krux code snippet
    words = mnemonic.split(" ")
    checksum_bits = 8 if len(words) == 24 else 4
    indexes = [WORDLIST.index(word) for word in words]
    bitstring = "".join([f"{bin(index)[2:]:0>11}" for index in indexes])[
        :-checksum_bits
    ]
    qr_data = int(bitstring, 2).to_bytes((len(bitstring) + 7) // 8, "big")

    # Prints ascii QR code
    qr_code = QRCode()
    qr_code.add_data(qr_data)
    qr_string = StringIO()
    qr_code.print_ascii(out=qr_string, invert=True)
    print("Compact Seed QR:")
    print(qr_string.getvalue())

def _seed_numbers():
    seed_numbers = []
    words = mnemonic.split(" ")
    for word in words:
        seed_numbers.append(WORDLIST.index(word) + 1)
    print("BIP39 Seed Numbers: " + str(seed_numbers))

def _public_keys():
    print("Public Data:")
    pub_key = ec.PrivateKey(bip39.mnemonic_to_bytes(mnemonic, ignore_checksum=True)).get_public_key().serialize()[1:]
    print("Hex Public key: " + pub_key.hex())
    converted_bits = bech32.convertbits(pub_key, 8, 5)
    print(
        "Bech32 Public key: "
        + bech32.bech32_encode(bech32.Encoding.BECH32, "npub", converted_bits)
    )

def _print_common():
    _seed_numbers()
    _compact_seed_qr()
    _public_keys()

print("Private Data:")
if len(sys.argv) == 2:
    input_data = sys.argv[1]
    if len(input_data) == 64:  # bytes input
        try:
            entropy_bytes = bytes.fromhex(input_data)
        except IOError:
            print("Invalid string, must be a string of bytes")
            sys.exit()
        mnemonic = bip39.mnemonic_from_bytes(entropy_bytes)
        print("Seed words: " + str(mnemonic))
        converted_bits = bech32.convertbits(bytearray.fromhex(input_data), 8, 5)
        print(
            "Bech32 Private Key: "
            + bech32.bech32_encode(bech32.Encoding.BECH32, "nsec", converted_bits)
        )
        _print_common()
    elif len(input_data) == 63 and input_data.startswith("nsec"):  # bech32 input
        spec, hrp, data = bech32.bech32_decode(input_data)
        decoded = bech32.convertbits(data, 5, 8, False)
        print("Hex Private Key: " + bytes(decoded).hex())
        mnemonic = bip39.mnemonic_from_bytes(bytes(decoded))
        print("Seed words: " + str(mnemonic))
        _print_common()

    else:
        print("Invalid keys")
else:
    if len(sys.argv) == 25:
        mnemonic = " ".join(sys.argv[1:])
        entropy = bip39.mnemonic_to_bytes(mnemonic, ignore_checksum=True)
        print("Hex Private Key: " + str(entropy.hex()))
        converted_bits = bech32.convertbits(entropy, 8, 5)
        print(
            "Bech32 Private key: "
            + bech32.bech32_encode(bech32.Encoding.BECH32, "nsec", converted_bits)
        )
        _print_common()
    else:
        print("Inform a 64 bytes private key or a 24 BIP39 words seed")
        print(str(len(sys.argv) - 1) + " words were given")