https://gitea.blesmrt.net/exa/codecrypt Codecrypt The post-quantum cryptography tool. About This is a GnuPG-like unix program for encryption and signing that uses only quantum-computer-resistant algorithms: - McEliece cryptosystem (compact QC-MDPC variant) for encryption - Hash-based Merkle tree algorithm (FMTSeq variant) for digital signatures Codecrypt is free software. The code is licensed under terms of LGPL3 in a good hope that it will make combinations with other tools easier. Why this? Go read http://pqcrypto.org/ Links - infopage: http://e-x-a.org/codecrypt/ - package downloads: http://e-x-a.org/codecrypt/files/ Distro packages - Gentoo packages: https://packages.gentoo.org/packages/app-crypt/codecrypt with current ebuild usually available at http://e-x-a.org/codecrypt/files - Debian packages: apt-get install codecrypt - Arch linux: see https://aur.archlinux.org/packages/codecrypt/ - Windows port is maintained separately here: https://github.com/mike805/codecrypt-win32 Language wrappers: - Python bindings: https://github.com/mike805/codecrypt-python/ Documentation There is a complete, UNIXy manual page supplied with the package. You can view it online here: http://e-x-a.org/codecrypt/ccr.1.html Used cryptography overview To achieve the stated goal, codecrypt uses a lot of (traditional, but "quantum-secure") cryptographic primitives. Choices of primitives were based on easy auditability of design, simplicity and provided security. The git repo of codecrypt contains doc/papers with an unsorted heap of academic papers and slides about relevant topics. Stream ciphers used: - ChaCha20, the recommended choice from djb - XSynd stream cipher as an interesting and nontraditional candidate also based on assumptions from coding theory; used NUMS (it requires lot of NUMS) are explained in doc/nums directory in the repo. - Arcfour for initial simplicity of implementation. After recent statistical attacks I cannot recommend using any RC4 variant anymore, but provided padding and the "offline-only" usage of codecrypt keeps the usage mostly secure. CRHFs used: - Cubehash variants were selected for implementation ease, really clean design, quite good speed and flexibility of parameter choices. This is also the only hash possibility when Crypto++ library is not linked to codecrypt. KeyIDs are CUBE256 hashes of corresponding serialized public keys. - ripemd128 for small hashes - tiger192 is used as an alternative for Cubehash for 192bit hashes - There's always a variant with SHA-256, SHA-384 or SHA-512. Signature algorithms: - FMTSeq with many possibilities and combinations of aforementioned CRHFs - SPHINCS256 support is scheduled for next release Encryption algorithms: - MDPC McEliece on quasi-cyclic matrices. The implementation uses some tricks to speedup the (pretty slow) cyclic matrix multiplication (most notably libfftm3 in this version). For padding using the Fujisaki-Okamoto scheme, the cipher requires a stream cipher and a CRHF, used ciphers and CRHFs are specified in the algorithm name -- e.g. MCEQCMDPC128FO-CUBE256-CHACHA20 means that the parameters are tuned to provide 128bit security, uses CUBE256 hash, and ChaCha20 stream cipher. - Quasi-dyadic McEliece was included in codecrypt as an original algorithm, but is now broken and prints a warning message on any usage. Caveats: Cryptography is not intended for "online" use, because some algorithms (especially the MDPC decoding) are (slightly) vulnerable to timing attacks. Quick How-To Everything is meant to work mostly like GnuPG, but with some good simplicity margin. Let's play with random data! ccr -g help ccr -g sig --name "John Doe" # your signature key ccr -g enc --name "John Doe" # your encryption key ccr -K #watch the generated keys ccr -k ccr -p -a -o my_pubkeys.asc -F Doe # export your pubkeys for friends #(now you should exchange the pubkeys with friends) #see what people sent us, possibly check the fingerprints ccr -inaf < friends_pubkeys.asc #import Frank's key and rename it ccr -ia -R friends_pubkeys.asc --name "Friendly Frank" #send a nice message to Frank (you can also specify him by @12345 keyid) ccr -se -r Frank < Document.doc > Message_to_frank.ccr #receive a reply ccr -dv -o Decrypted_verified_reply.doc <Reply_from_frank.ccr #rename other's keys ccr -m Frank -N "Unfriendly Frank" #and delete pukeys of everyone who's Unfriendly ccr -x Unfri #create hashfile from a large file ccr -sS hashfile.ccr < big_data.iso #verify the hashfile ccr -vS hashfile.ccr < the_same_big_data.iso #create (ascii-armored) symmetric key and encrypt a large file ccr -g sha256,chacha20 -aS symkey.asc ccr -eaS symkey.asc -R big_data.iso -o big_data_encrypted.iso #decrypt a large file ccr -daS symkey.asc <big_data_encrypted.iso >big_data.iso #password-protect all your private keys ccr -L #protect a symmetric key using another symmetric key ccr -L -S symkey1 -w symkey2 #password-protect symkey2 with a custom cipher ccr -L -S symkey2 -w @xsynd,cube512 Option reference For completeness I add listing of all options here (also available from ccr --help) Usage: ./ccr [options] Common options: -h, --help display this help -V, --version display version information -T, --test perform (probably nonexistent) testing/debugging stuff Global options: -R, --in set input file, default is stdin -o, --out set output file, default is stdout -E, --err the same for stderr -a, --armor use ascii-armored I/O -y, --yes assume that answer is `yes' everytime Actions: -s, --sign sign a message -v, --verify verify a signed message -e, --encrypt encrypt a message -d, --decrypt decrypt an encrypted message Action options: -r, --recipient encrypt for given user -u, --user use specified secret key -C, --clearsign work with cleartext signatures -b, --detach-sign specify file with detached signature -S, --symmetric enable symmetric mode of operation where encryption is done using symmetric cipher and signatures are hashes, and specify a filename of symmetric key or hashes Key management: -g, --gen-key generate keys for specified algorithm -g help list available cryptographic algorithms -k, --list list the contents of keyring -K, --list-secret -i, --import import keys -I, --import-secret -p, --export export keys -P, --export-secret -x, --delete delete matching keys -X, --delete-secret -m, --rename rename matching keys -M, --rename-secret -L, --lock lock secrets -U, --unlock unlock secrets Key management options: -F, --filter only work with keys with matching names -f, --fingerprint format full key IDs nicely for human eyes -N, --name specify a new name for renaming or importing -n, --no-action on import, only show what would be imported -w, --with-lock specify the symmetric key for (un)locking the secrets -w @SPEC ask for password and expand it to a symmetric key of type SPEC for (un)locking the secret Disclaimer Codecrypt eats data. Use it with caution. Read the F manual. Author is a self-taught cryptographer.