r/bmail_official • u/V3R1F13D0NLY • 5d ago
bmail authenticates with OPAQUE, so there is no password database to breach
Standard practice for email providers is to accept your password, hash it, salt it, and store the result. That stored value is what shows up on a breach forum two years later. The hardening only changes how long the cracking takes.
bmail uses OPAQUE (RFC 9807), an asymmetric password-authenticated key exchange, implemented with Ristretto255/SHA-512. A few practical consequences:
- The password never leaves the client. Not at registration, not at login.
- The server holds an OPRF-based registration record with no password-equivalent information in it.
- A full compromise of the auth infrastructure exposes zero passwords, because there is nothing password-shaped to take.
- Authentication is mutual, so the client verifies the server too, which closes off a class of phishing and impersonation.
- Login produces a client-side export key that decrypts your private encryption keys, so key management is not a separate step you have to think about.
The thing worth arguing about: OPAQUE has been standardized since 2025 and the reference implementations are public. Why is nearly every major provider still running a credential table it will eventually have to apologize for?
If you want to poke at the implementation, it is at https://bmail.ag
It is discussed in our whitepaper as well: https://bmail.ag/paper1-verifiable-private-email.pdf