Function nrfxlib_sys::ocrypto_chacha20_init

pub unsafe extern "C" fn ocrypto_chacha20_init(
    ctx: *mut ocrypto_chacha20_ctx,
    n: *const u8,
    n_len: usize,
    key: *const u8,
    count: u32
)

Incremental ChaCha20 Encoder.

This group of functions can be used to incrementally compute the ChaCha20 encryption for a given message and key, by segmenting a message into smaller chunks.

Use pattern:

Encoding/Decoding: @code ocrypto_chacha20_init(ctx, n, n_len, key, count); ocrypto_chacha20_update(ctx, c, m, m_len); … ocrypto_chacha20_update(ctx, c, m, m_len); @endcode / /@{*/ / ChaCha20 encoder initialization.

The generator state * ctx - is initialized by this function.

• ctx - Encoder state.
• n - Nonce. May be NULL.
• n_len - Nonce length. 0 <= * n_len - <= * ocrypto_chacha20_NONCE_BYTES_MAX - .
• key - Authentication key. May be NULL.
• count - Initial block counter, usually 0 or 1.

@remark If * key - is NULL only * n - and * count - are set. If * n - is NULL only * key - is set. Both * key - and * n - must be set before update is called. @remark When reusing an encryption key * key - for a different message, a different nonce * n - or initial block counter * count - must be used.