a replacement for gpg which can encrypt/sign/verify
opmsg is a replacement for gpg which can encrypt/sign/verify your mails or
create/verify detached signatures of local files. Even though the opmsg output
looks similar, the concept is entirely different.

Features:

- Perfect Forward Secrecy (PFS) by means of ECDH or DH Kex
- native EC or RSA fallback if no (EC)DH keys left
- fully compliant to existing SMTP/IMAP/POP etc. standards; no need to touch
  any mail daemon/client/agent code
- signing messages is mandatory
- OTR-like deniable signatures if demanded
- easy creation and throw-away of ids
- support for 1:1 key bindings to auto-select source key per destination
- adds the possibility to (re-)route messages different from mail address to
  defeat meta data collection
- configurable, well-established hash and crypto algorithms and key lengths
  (RSA, DH, ECC, AES, Chacha)
- straight forward and open key storage, basically also managable via cat,
  shred -u and ls on the cmdline
- seamless mutt integration
- Key format suitable for easy use with QR-codes
- optional cross-domain ECDH Kex

opmsg builds fine with any of the OpenSSL, LibreSSL and BoringSSL libcrypto
libraries. Building against BoringSSL is not recommended due to missing
blowfish and ripemd algorithms.

Maintainer: The OpenBSD ports mailing-list <ports@openbsd.org>

WWW: https://github.com/stealth/opmsg
