Function nrfxlib_sys::ocrypto_chacha20_encode
source · pub unsafe extern "C" fn ocrypto_chacha20_encode(
c: *mut u8,
m: *const u8,
m_len: usize,
n: *const u8,
n_len: usize,
key: *const u8,
count: u32
)
Expand description
ChaCha20 cipher stream encoder.
The message * m
- is encrypted by applying the XOR operation with a pseudo
random cipher stream derived from the encryption key * key
- , the nonce * n
- , and
the initial block counter * count
- .
Calling the function a second time with the generated ciphertext as input
message * m
- decrypts it back to the original message.
c
- Generated ciphertext. Same length as input message.m
- Input message.m_len
- Length of *c
- and *m
- .n
- Nonce.n_len
- Nonce length. 0 <= *n_len
- <= *ocrypto_chacha20_NONCE_BYTES_MAX
- .key
- Encryption key.count
- Initial block counter.
@remark * c
- may be same as * m
- .
@remark When reusing an encryption key * key
- for a different message * m
- , a
different nonce * n
- or initial block counter * count
- must be used.