security/opmsg 1.78sp2 OpenBSD

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.