crypto_encrypt_buffer
enclen = crypto_encrypt_buffer(argv[2], strlen(argv[2]),
size_t crypto_encrypt_buffer(const char *, size_t, char *, size_t);
enclen = crypto_encrypt_buffer(evp, evplen, encbuf, sizeof encbuf);
size_t crypto_encrypt_buffer(const char *, size_t, char *, size_t);