XSalsa20-Poly1305 authenticated symmetric encryption (NaCl secretbox).
Ciphertext layout: nonce (24 bytes) || ciphertext (plaintext_len + 16 byte MAC)
This is the same format produced by libsodium's crypto_secretbox_easy with a
prepended random nonce, making it compatible with existing NaCl implementations.
Usage
key = MetamorphicCrypto.Keys.generate_key()
# Encrypt/decrypt UTF-8 strings
{:ok, ct} = MetamorphicCrypto.SecretBox.encrypt_string("hello", key)
{:ok, "hello"} = MetamorphicCrypto.SecretBox.decrypt_string(ct, key)
# Encrypt/decrypt raw bytes (as base64)
plaintext_b64 = Base.encode64("raw bytes")
{:ok, ct} = MetamorphicCrypto.SecretBox.encrypt(plaintext_b64, key)
{:ok, ^plaintext_b64} = MetamorphicCrypto.SecretBox.decrypt(ct, key)Summary
Functions
Decrypt base64 ciphertext, returning plaintext as base64.
Decrypt base64 ciphertext to a UTF-8 string.
Decrypt base64 ciphertext to a UTF-8 string, raising on failure.
Encrypt raw bytes (passed as base64) with a base64 key.
Encrypt a UTF-8 string with a base64 key.
Encrypt a UTF-8 string, raising on failure.
Functions
@spec decrypt(ciphertext_b64 :: String.t(), key_b64 :: String.t()) :: {:ok, String.t()} | {:error, String.t()}
Decrypt base64 ciphertext, returning plaintext as base64.
Returns {:ok, plaintext_b64} or {:error, reason}.
@spec decrypt_string(ciphertext_b64 :: String.t(), key_b64 :: String.t()) :: {:ok, String.t()} | {:error, String.t()}
Decrypt base64 ciphertext to a UTF-8 string.
Returns {:ok, plaintext} or {:error, reason}.
Example
{:ok, "my secret"} = MetamorphicCrypto.SecretBox.decrypt_string(ct, key)Decrypt base64 ciphertext to a UTF-8 string, raising on failure.
Example
"hello" = MetamorphicCrypto.SecretBox.decrypt_string!(ct, key)@spec encrypt(plaintext_b64 :: String.t(), key_b64 :: String.t()) :: {:ok, String.t()} | {:error, String.t()}
Encrypt raw bytes (passed as base64) with a base64 key.
Returns {:ok, ciphertext_b64} or {:error, reason}.
@spec encrypt_string(plaintext :: String.t(), key_b64 :: String.t()) :: {:ok, String.t()} | {:error, String.t()}
Encrypt a UTF-8 string with a base64 key.
Returns {:ok, ciphertext_b64} or {:error, reason}.
Example
key = MetamorphicCrypto.Keys.generate_key()
{:ok, ct} = MetamorphicCrypto.SecretBox.encrypt_string("my secret", key)Encrypt a UTF-8 string, raising on failure.
Example
ct = MetamorphicCrypto.SecretBox.encrypt_string!("hello", key)