crypto-box - encrypt and authenticate a stream of data using asymmetric (public-key) cryptography
crypto-box [ publickeyfile ] [ secretkeyfile ]
Reads a stream of data from standard input, and encrypts it using public-key authenticated cryptography from NaCl (the Networking and Cryptography library). The encrypted data is output in a format specifically for crypto-box-open(1).
The publickeyfile argument should point to a file with the public key of the intended message recipient. If this argument is not given, the environment variable NACL_PUBLICKEY_FILE will be used instead.
The secretkeyfile argument should point to a file with the secret key of the message sender. If this argument is not given, the environment variable NACL_SECRETKEY_FILE will be used instead.
Reads input in chunks, and outputs the following for each chunk:
1) A nonce for the chunk, encoded as a netstring
2) An encrypted chunk, encoded as a netstring
Normally, crypto-box exits with 0.
If invalid arguments are given, crypto-box exits with 100.
If an error occurs, crypto-box exits with 111.
This program is a simply a wrapper around the crypto_box function provided by NaCl, the Networking and Cryptography library by Daniel J. Bernstein and Tanja Lange. See the official website http://nacl.cr.yp.to/ for details.