Rust

AES Encrypt and Decrypt a File

_LANGUAGE_ demonstrates how to AES encrypt a file of any size, and then decrypt. Rust

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

let crypt = chilkat::Crypt2::new();

crypt.set_crypt_algorithm("aes");

// CipherMode may be "ecb" or "cbc"
crypt.set_cipher_mode("cbc");

// KeyLength may be 128, 192, 256
crypt.set_key_length(256);

// The padding scheme determines the contents of the bytes
// that are added to pad the result to a multiple of the
// encryption algorithm's block size.  AES has a block
// size of 16 bytes, so encrypted output is always
// a multiple of 16.
crypt.set_padding_scheme(0);

// An initialization vector is required if using CBC mode.
// ECB mode does not use an IV.
// The length of the IV is equal to the algorithm's block size.
// It is NOT equal to the length of the key.
let iv_hex = "000102030405060708090A0B0C0D0E0F".to_string();
crypt.set_encoded_iv(&iv_hex, "hex");

// The secret key must equal the size of the key.  For
// 256-bit encryption, the binary secret key is 32 bytes.
// For 128-bit encryption, the binary secret key is 16 bytes.
let key_hex = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F".to_string();
crypt.set_encoded_key(&key_hex, "hex");

// Encrypt a file, producing the .aes as output.
// The input file is unchanged, the output .aes contains the encrypted
// contents of the input file.

// Note: The .aes output file has no file format.  It is simply a stream
// of bytes that resembles random binary data.
let mut in_file = "/Users/chilkat/testData/pdf/sample.pdf".to_string();
let mut out_file = "/Users/chilkat/testData/p7m/sample.pdf.aes".to_string();
if crypt.ck_encrypt_file(&in_file, &out_file).is_err() {
    println!("{}", crypt.last_error_text());
    return;
}

// For demonstration purposes, a different instance of the object will be used
// for decryption.
let decrypt = chilkat::Crypt2::new();

// All settings must match to be able to decrypt:
decrypt.set_crypt_algorithm("aes");
decrypt.set_cipher_mode("cbc");
decrypt.set_key_length(256);
decrypt.set_padding_scheme(0);
decrypt.set_encoded_iv(&iv_hex, "hex");
decrypt.set_encoded_key(&key_hex, "hex");

// Decrypt the .aes
in_file = "/Users/chilkat/testData/p7m/sample.pdf.aes".to_string();
out_file = "/Users/chilkat/testData/pdf/recovered.pdf".to_string();
if decrypt.ck_decrypt_file(&in_file, &out_file).is_err() {
    println!("{}", decrypt.last_error_text());
    return;
}

println!("Success!");