remailers

A toolkit for anonymous messaging with PGP over Usenet and Tor email: hashed/encrypted subjects (hSub/eSub), nym-server (ZAX) registration, and SOCKS/Tor SMTP. Built on top of usenet.

For research and privacy education. The public nym/remailer network is largely historical. Treat the bundled server definitions as starting points.

Install

pip install remailers

Quickstart

Generate (or load) a PGP identity:

from remailers import Credentials

creds = Credentials("my_key.asc", name="PythonicAnon")
print(creds.pubkey)

Hashed and encrypted subjects: let a recipient spot a message meant for them without revealing the subject:

from remailers import create_hsub, match_hsub, create_esub, match_esub

hsub = create_hsub("evil dolphin captain")
assert match_hsub(hsub, "evil dolphin captain")

esub = create_esub("evil dolphin captain", key="shared-secret")
assert match_esub("evil dolphin captain", "shared-secret", esub)

Post and retrieve anonymous messages via alt.anonymous.messages:

from usenet import UsenetServer
from remailers import Credentials, AnonBox, create_hsub

creds = Credentials("my_key.asc")
hsub = create_hsub("evil dolphin captain")
ciphertext = creds.encrypt("meet at noon")

with UsenetServer("news.neodome.net") as server:
    server.post(ciphertext, hsub, "alt.anonymous.messages")

inbox = AnonBox(creds, UsenetServer("news.neodome.net"))
for article in inbox.retrieve_by_subject("evil dolphin captain"):
    print(article.text)

ZAX nym servers and Tor email are in remailers.zax and remailers.mail. See examples/.

Security notes

• Initialization vectors come from os.urandom (remailers.utils.generate_iv).
• hSub uses SHA-256. eSub uses Blowfish for Type-I compatibility: it exists for interop with the legacy remailer ecosystem, not as modern AEAD.
• Message bodies are protected by PGP (RSA-4096, AES-256), not by the subject scheme.

Testing

pip install -e .[test]
pytest test/

Tests are offline: subject round-trips, IV entropy, and a PGP encrypt/decrypt cycle with a freshly generated key.

License

Apache-2.0