gpg-fingerprint-filter-gpu

Generate an OpenPGP key whose fingerprint matches a specific pattern.

Get your lucky key! CUDA powered, so fast!

$ ./gpg-fingerprint-filter-gpu --help
  gpg-fingerprint-filter-gpu [OPTIONS] <pattern> <output>

  <pattern>                   Key pattern to match, for example 'X{8}|(AB){4}'
  <output>                    Save secret key to this path
  -a, --algorithm <ALGO>      PGP key algorithm [default: rsa]
  -t, --time-offset <N>       Max key timestamp offset [default: 15552000]
  -w, --thread-per-block <N>  CUDA thread number per block [default: 512]
  -j, --gpg-thread <N>        Number of threads to generate keys [default: 12]
  -b, --base-time <N>         Base key timestamp (0 means current time) [default: 0]
  -h, --help

Pattern

• Only matches end part of a string.
• A hex digit means itself.
• Other Latin alphabets (g to z) are to match any hex digit.
• {N} to repeat previous digit or group for N times.
• (PATTERN) a group pattern.
• Use | to split multiple patterns.

Examples:

• deadbeef equals to regex deadbeef$
• x{8} equals to regex ([0-9a-f])\1{7}$
• (xy){4} equals to regex ([0-9a-f][0-9a-f])\1{3}$
• xxxxa{4} equals to regex ([0-9a-f])\1{3}aaaa$

Import Key

Import the generated private key:

$ gpg --allow-non-selfsigned-uid --import private.pgp

The private key file doesn't have a self-signed UID on it. GPG will display NONAME as the default UID. You need to add a valid UID and remove the default one to make the key usable:

$ gpg --edit-key <KEY_FINGERPRINT>
gpg> adduid
Real name: Your Name Here
Email address: your_email@example.com
......
gpg> uid 1
gpg> deluid
gpg> save

Merge Key

Since cv25519 cannot be used as primary key, you need to merge the generated key with an existing key:

Reference: https://security.stackexchange.com/questions/32935/migrating-gpg-master-keys-as-subkeys-to-new-master-key

TLDR:

1. Primary key should be created earlier than subkey.
2. To persevere the subkey fingerprint, you need perserve the subkey creation time.

gpg -k --with-colons
gpg --with-keygrip -k
gpg --expert --faked-system-time="[sub key timestamp]\!" --ignore-time-conflict --edit-key [master key id]
addkey
13 (existing key)