crypto.cipher #

fn new_cbc(b Block, iv []u8) Cbc

new_cbc returns a DesCbc which encrypts in cipher block chaining mode, using the given Block. The length of iv must be the same as the Block's block size.

fn new_cfb_decrypter(b Block, iv []u8) Cfb

new_cfb_decrypter returns a Cfb which decrypts with cipher feedback mode, using the given Block. The iv must be the same length as the Block's block size

fn new_cfb_encrypter(b Block, iv []u8) Cfb

new_cfb_encrypter returns a Cfb which encrypts with cipher feedback mode, using the given Block. The iv must be the same length as the Block's block size

fn new_ctr(b Block, iv []u8) Ctr

new_ctr returns a Ctr which encrypts/decrypts using the given Block in counter mode. The length of iv must be the same as the Block's block size.

fn new_ofb(b Block, iv []u8) Ofb

new_ofb returns a Ofb that encrypts or decrypts using the block cipher b in output feedback mode. The initialization vector iv's length must be equal to b's block size.

fn safe_xor_bytes(mut dst []u8, a []u8, b []u8, n int)

safe_xor_bytes XORs the bytes in a and b into dst it does so n times. Please note: n needs to be smaller or equal than the length of a and b.

fn xor_bytes(mut dst []u8, a []u8, b []u8) int

Note: Implement other versions (joe-c)xor_bytes xors the bytes in a and b. The destination should have enough space, otherwise xor_bytes will panic. Returns the number of bytes xor'd.

fn xor_words(mut dst []u8, a []u8, b []u8)

xor_words XORs multiples of 4 or 8 bytes (depending on architecture.) The slice arguments a and b are assumed to be of equal length.

interface AEAD {
	// nonce_size returns the size of nonce (in bytes) used by this AEAD that must be
	// passed to `.encrypt` or `.decrypt`.
	nonce_size() int
	// overhead returns the maximum difference between the lengths of a plaintext and its ciphertext.
	overhead() int
	// encrypt encrypts and authenticates the provided plaintext along with the nonce and
	// additional data in `ad`. The nonce must be `nonce_size()` bytes long and unique
	// for all time, for a given key. It returns encrypted (and authenticated) ciphertext bytes
	// where its encoded form is up to implementation and not dictated by the interfaces.
	// Commonly, its contains encrypted text plus some authentication tag, and maybe some other bytes.
	encrypt(plaintext []u8, nonce []u8, ad []u8) ![]u8
	// decrypt decrypts and authenticates (verifies) the provided ciphertext along with a nonce, and
	// additional data. The nonce must be `nonce_size()` bytes long and both it and the additional data
	// must match the value passed to `encrypt`.
	// Its returns the verified plaintext on success, or errors on fails.
	decrypt(ciphertext []u8, nonce []u8, ad []u8) ![]u8
}

AEAD provides an authenticated encryption with associated data for encryption (decryption).

interface Block {
	block_size int // block_size returns the cipher's block size.
	encrypt(mut dst []u8, src []u8) // Encrypt encrypts the first block in src into dst.
	// Dst and src must overlap entirely or not at all.
	decrypt(mut dst []u8, src []u8) // Decrypt decrypts the first block in src into dst.
	// Dst and src must overlap entirely or not at all.
}

A Block represents an implementation of block cipher using a given key. It provides the capability to encrypt or decrypt individual blocks. The mode implementations extend that capability to streams of blocks.

interface BlockMode {
	block_size int // block_size returns the mode's block size.
	crypt_blocks(mut dst []u8, src []u8) // crypt_blocks encrypts or decrypts a number of blocks. The length of
	// src must be a multiple of the block size. Dst and src must overlap
	// entirely or not at all.
	//
	// If len(dst) < len(src), crypt_blocks should panic. It is acceptable
	// to pass a dst bigger than src, and in that case, crypt_blocks will
	// only update dst[:len(src)] and will not touch the rest of dst.
	//
	// Multiple calls to crypt_blocks behave as if the concatenation of
	// the src buffers was passed in a single run. That is, BlockMode
	// maintains state and does not reset at each crypt_blocks call.
}

A BlockMode represents a block cipher running in a block-based mode (CBC, ECB etc).

interface Stream {
mut:
	// xor_key_stream XORs each byte in the given slice with a byte from the
	// cipher's key stream. Dst and src must overlap entirely or not at all.
	//
	// If len(dst) < len(src), xor_key_stream should panic. It is acceptable
	// to pass a dst bigger than src, and in that case, xor_key_stream will
	// only update dst[:len(src)] and will not touch the rest of dst.
	//
	// Multiple calls to xor_key_stream behave as if the concatenation of
	// the src buffers was passed in a single run. That is, Stream
	// maintains state and does not reset at each xor_key_stream call.
	xor_key_stream(mut dst []u8, src []u8)
}

A Stream represents a stream cipher.

fn (mut x Cbc) free()

free the resources taken by the Cbc x

fn (mut x Cbc) encrypt_blocks(mut dst_ []u8, src_ []u8)

encrypt_blocks encrypts the blocks in src_ to dst_. Please note: dst_ is mutable for performance reasons.

fn (mut x Cbc) decrypt_blocks(mut dst []u8, src []u8)

decrypt_blocks decrypts the blocks in src to dst. Please note: dst is mutable for performance reasons.

fn (mut x Cfb) free()

free the resources taken by the Cfb x

fn (mut x Cfb) xor_key_stream(mut dst []u8, src []u8)

xor_key_stream xors each byte in the given slice with a byte from the key stream.

fn (mut x Ctr) free()

free the resources taken by the Ctr c

fn (mut x Ctr) xor_key_stream(mut dst []u8, src []u8)

xor_key_stream xors each byte in the given slice with a byte from the key stream.

fn (mut x Ofb) xor_key_stream(mut dst []u8, src []u8)

xor_key_stream xors each byte in the given slice with a byte from the key stream.