56 lines
2.3 KiB
V
56 lines
2.3 KiB
V
// The source code refers to the go standard library, which will be combined with AES in the future.
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module cipher
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// A Block represents an implementation of block cipher
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// using a given key. It provides the capability to encrypt
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// or decrypt individual blocks. The mode implementations
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// extend that capability to streams of blocks.
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interface Block {
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block_size int // block_size returns the cipher's block size.
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encrypt(mut dst []byte, src []byte) // Encrypt encrypts the first block in src into dst.
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// Dst and src must overlap entirely or not at all.
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decrypt(mut dst []byte, src []byte) // Decrypt decrypts the first block in src into dst.
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// Dst and src must overlap entirely or not at all.
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}
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// A Stream represents a stream cipher.
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interface Stream {
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// xor_key_stream XORs each byte in the given slice with a byte from the
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// cipher's key stream. Dst and src must overlap entirely or not at all.
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//
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// If len(dst) < len(src), xor_key_stream should panic. It is acceptable
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// to pass a dst bigger than src, and in that case, xor_key_stream will
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// only update dst[:len(src)] and will not touch the rest of dst.
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//
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// Multiple calls to xor_key_stream behave as if the concatenation of
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// the src buffers was passed in a single run. That is, Stream
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// maintains state and does not reset at each xor_key_stream call.
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xor_key_stream(mut dst []byte, src []byte)
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}
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// A BlockMode represents a block cipher running in a block-based mode (CBC,
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// ECB etc).
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interface BlockMode {
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block_size int // block_size returns the mode's block size.
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crypt_blocks(mut dst []byte, src []byte) // crypt_blocks encrypts or decrypts a number of blocks. The length of
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// src must be a multiple of the block size. Dst and src must overlap
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// entirely or not at all.
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//
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// If len(dst) < len(src), crypt_blocks should panic. It is acceptable
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// to pass a dst bigger than src, and in that case, crypt_blocks will
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// only update dst[:len(src)] and will not touch the rest of dst.
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//
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// Multiple calls to crypt_blocks behave as if the concatenation of
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// the src buffers was passed in a single run. That is, BlockMode
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// maintains state and does not reset at each crypt_blocks call.
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}
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// Utility routines
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// fn dup(p []byte) []byte {
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// q := make([]byte, p.len)
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// copy(mut q, p)
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// return q
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// }
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