aes_cbc: Symmetric AES encryption

aes_cbcR Documentation

Symmetric AES encryption


Low-level symmetric encryption/decryption using the AES block cipher in CBC mode. The key is a raw vector, for example a hash of some secret. When no shared secret is available, a random key can be used which is exchanged via an asymmetric protocol such as RSA. See rsa_encrypt() for a worked example or encrypt_envelope() for a high-level wrapper combining AES and RSA.


aes_ctr_encrypt(data, key, iv = rand_bytes(16))

aes_ctr_decrypt(data, key, iv = attr(data, "iv"))

aes_cbc_encrypt(data, key, iv = rand_bytes(16))

aes_cbc_decrypt(data, key, iv = attr(data, "iv"))

aes_gcm_encrypt(data, key, iv = rand_bytes(12))

aes_gcm_decrypt(data, key, iv = attr(data, "iv"))

aes_keygen(length = 16)



raw vector or path to file with data to encrypt or decrypt


raw vector of length 16, 24 or 32, e.g. the hash of a shared secret


raw vector of length 16 (aes block size) or NULL. The initialization vector is not secret but should be random


how many bytes to generate. Usually 16 (128-bit) or 12 (92-bit) for aes_gcm


# aes-256 requires 32 byte key
passphrase <- charToRaw("This is super secret")
key <- sha256(passphrase)

# symmetric encryption uses same key for decryption
x <- serialize(iris, NULL)
y <- aes_cbc_encrypt(x, key = key)
x2 <- aes_cbc_decrypt(y, key = key)
stopifnot(identical(x, x2))

openssl documentation built on May 25, 2022, 9:09 a.m.