Function nrfxlib_sys::ocrypto_chacha20_poly1305_encrypt

source · 
pub unsafe extern "C" fn ocrypto_chacha20_poly1305_encrypt(
    tag: *mut u8,
    c: *mut u8,
    m: *const u8,
    m_len: usize,
    a: *const u8,
    a_len: usize,
    n: *const u8,
    n_len: usize,
    k: *const u8
)
Expand description

AEAD ChaCha20-Poly1305 encrypt.

The message * m - is encrypted using a ChaCha20 cipher stream derived from the encryption key * k - and the nonce * n - . The resulting ciphertext has the same length * m_len - as the input message * m - and is put into * c - .

Additionally, the ciphertext * c - , as well as the additional authenticated data * a - , is authenticated with a tag that is generated with Poly1305 using a unique subkey derived from * k - and * n - , and then put into * tag - .

  • tag - Generated authentication tag.
  • c - Generated ciphertext. Same length as input message.
  • m - Input message.
  • m_len - Length of * m - and * c - .
  • a - Additional authenticated data.
  • a_len - Length of * a - . May be 0.
  • n - Nonce.
  • n_len - Length of * n - . 0 <= * n_len - <= * ocrypto_chacha20_poly1305_NONCE_BYTES_MAX - .
  • k - Encryption key.

@remark * c - may be same as * m - .

@remark When reusing an encryption key * k - for a different message * m - or different additional authenticated data * a - , a different nonce * n - must be used.