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pkg/cryptstate, pkg/cryptstate/ocb2: move OCB2 tag verification into ocb2.Decrypt.
This commit is contained in:
Mikkel Krautz
parent
2b12adc014
commit
154b7938d3
3 changed files with 453 additions and 450 deletions
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@ -92,8 +92,8 @@ func (cs *CryptState) Decrypt(dst, src []byte) error {
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return errors.New("cryptstate: plain_len and src len mismatch")
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}
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var tag [ocb2.TagSize]byte
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ivbyte := src[0]
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tag := src[1:4]
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restore := false
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lost := 0
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late := 0
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@ -167,13 +167,10 @@ func (cs *CryptState) Decrypt(dst, src []byte) error {
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}
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}
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ocb2.Decrypt(cs.cipher, dst, src[4:], cs.DecryptIV, tag[:])
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for i := 0; i < 3; i++ {
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if tag[i] != src[i+1] {
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cs.DecryptIV = saveiv
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return errors.New("tag mismatch")
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}
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ok := ocb2.Decrypt(cs.cipher, dst, src[4:], cs.DecryptIV, tag[:])
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if !ok {
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cs.DecryptIV = saveiv
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return errors.New("cryptstate: tag mismatch")
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}
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cs.decryptHistory[cs.DecryptIV[0]] = cs.DecryptIV[0]
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@ -1,237 +1,247 @@
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// Copyright (c) 2010-2012 The Grumble Authors
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// The use of this source code is goverened by a BSD-style
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// license that can be found in the LICENSE-file.
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// Package ocb2 implements the version 2 of the OCB authenticated-encryption algorithm.
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// OCB2 is specified in http://www.cs.ucdavis.edu/~rogaway/papers/draft-krovetz-ocb-00.txt.
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//
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// Note that this implementation is limited to block ciphers with a block size of 128 bits.
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//
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// It should also be noted that OCB's author, Phil Rogaway <rogaway@cs.ucdavis.edu>, holds
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// several US patents on the algorithm. This should be considered before using this code
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// in your own projects. See OCB's FAQ for more info:
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// http://www.cs.ucdavis.edu/~rogaway/ocb/ocb-faq.htm#patent:phil
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//
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// The Mumble Project has a license to use OCB mode in its BSD licensed code on a royalty
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// free basis.
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package ocb2
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import "crypto/cipher"
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const (
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// BlockSize defines the block size that this particular implementation
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// of OCB2 is made to work on.
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BlockSize = 16
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// TagSize specifies the length in bytes of a full OCB2 tag.
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// As per the specification, applications may truncate their
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// tags to a given length, but advocates that typical applications
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// should use a tag length of at least 8 bytes (64 bits).
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TagSize = BlockSize
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// NonceSize specifies the length in bytes of an OCB2 nonce.
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NonceSize = BlockSize
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)
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// zeros fills block with zero bytes.
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func zeros(block []byte) {
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for i := range block {
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block[i] = 0
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}
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}
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// xor outputs the bitwise exclusive-or of a and b to dst.
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func xor(dst []byte, a []byte, b []byte) {
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for i := 0; i < BlockSize; i++ {
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dst[i] = a[i] ^ b[i]
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}
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}
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// times2 performs the times2 operation, defined as:
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//
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// times2(S)
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// S << 1 if S[1] = 0, and (S << 1) xor const(bitlength(S)) if S[1] = 1.
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//
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// where const(n) is defined as
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//
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// const(n)
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// The lexicographically first n-bit string C among all
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// strings that have a minimal possible number of "1"
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// bits and which name a polynomial x^n + C[1] *
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// x^{n-1} + ... + C[n-1] * x^1 + C[n] * x^0 that is
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// irreducible over the field with two elements. In
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// particular, const(128) = num2str(135, 128). For
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// other values of n, refer to a standard table of
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// irreducible polynomials [G. Seroussi,
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// "Table of low-weight binary irreducible polynomials",
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// HP Labs Technical Report HPL-98-135, 1998.].
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//
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// and num2str(x, n) is defined as
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//
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// num2str(x, n)
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// The n-bit binary representation of the integer x.
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// More formally, the n-bit string S where x = S[1] *
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// 2^{n-1} + S[2] * 2^{n-2} + ... + S[n] * 2^{0}. Only
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// used when 0 <= x < 2^n.
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//
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// For our 128-bit block size implementation, this means that
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// the xor with const(bitlength(S)) if S[1] = 1 is implemented
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// by simply xor'ing the last byte with the number 135 when
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// S[1] = 1.
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func times2(block []byte) {
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carry := (block[0] >> 7) & 0x1
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for i := 0; i < BlockSize-1; i++ {
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block[i] = (block[i] << 1) | ((block[i+1] >> 7) & 0x1)
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}
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block[BlockSize-1] = (block[BlockSize-1] << 1) ^ (carry * 135)
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}
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// times3 performs the times3 operation, defined as:
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//
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// times3(S)
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// times2(S) xor S
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func times3(block []byte) {
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carry := (block[0] >> 7) & 0x1
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for i := 0; i < BlockSize-1; i++ {
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block[i] ^= (block[i] << 1) | ((block[i+1] >> 7) & 0x1)
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}
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block[BlockSize-1] ^= ((block[BlockSize-1] << 1) ^ (carry * 135))
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}
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// Encrypt encrypts the plaintext src and outputs the corresponding ciphertext into dst.
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// Besides outputting a ciphertext into dst, Encrypt also outputs an authentication tag
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// of ocb2.TagSize bytes into tag, which should be used to verify the authenticity of the
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// message on the receiving side.
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//
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// To ensure both authenticity and secrecy of messages, each invocation to this function must
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// be given an unique nonce of ocb2.NonceSize bytes. The nonce need not be secret (it can be
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// a counter), but it needs to be unique.
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//
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// The block cipher used in function must work on a block size equal to ocb2.BlockSize.
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// The tag slice used in this function must have a length equal to ocb2.TagSize.
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// The nonce slice used in this function must have a length equal to ocb2.NonceSize.
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// If any of the above are violated, Encrypt will panic.
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func Encrypt(cipher cipher.Block, dst []byte, src []byte, nonce []byte, tag []byte) {
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if cipher.BlockSize() != BlockSize {
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panic("ocb2: cipher blocksize is not equal to ocb2.BlockSize")
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}
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if len(nonce) != NonceSize {
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panic("ocb2: nonce length is not equal to ocb2.NonceSize")
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}
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if len(tag) != TagSize {
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panic("ocb2: tag length is not equal to ocb2.TagSize")
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}
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var (
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checksum [BlockSize]byte
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delta [BlockSize]byte
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tmp [BlockSize]byte
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pad [BlockSize]byte
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off int
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)
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cipher.Encrypt(delta[0:], nonce[0:])
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zeros(checksum[0:])
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remain := len(src)
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for remain > BlockSize {
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times2(delta[0:])
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xor(tmp[0:], delta[0:], src[off:off+BlockSize])
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cipher.Encrypt(tmp[0:], tmp[0:])
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xor(dst[off:off+BlockSize], delta[0:], tmp[0:])
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xor(checksum[0:], checksum[0:], src[off:off+BlockSize])
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remain -= BlockSize
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off += BlockSize
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}
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times2(delta[0:])
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zeros(tmp[0:])
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num := remain * 8
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tmp[BlockSize-2] = uint8((uint32(num) >> 8) & 0xff)
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tmp[BlockSize-1] = uint8(num & 0xff)
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xor(tmp[0:], tmp[0:], delta[0:])
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cipher.Encrypt(pad[0:], tmp[0:])
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copied := copy(tmp[0:], src[off:])
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if copied != remain {
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panic("ocb2: copy failed")
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}
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if copy(tmp[copied:], pad[copied:]) != (BlockSize - remain) {
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panic("ocb2: copy failed")
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}
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xor(checksum[0:], checksum[0:], tmp[0:])
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xor(tmp[0:], pad[0:], tmp[0:])
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if copy(dst[off:], tmp[0:]) != remain {
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panic("ocb2: copy failed")
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}
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times3(delta[0:])
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xor(tmp[0:], delta[0:], checksum[0:])
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cipher.Encrypt(tag[0:], tmp[0:])
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}
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// Decrypt takes a ciphertext and a nonce as its input and outputs a decrypted plaintext
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// and corresponding authentication tag.
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//
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// Before using the decrpyted plaintext, the application
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// should verify that the computed authentication tag matches the tag that was produced when
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// encrypting the message (taking into consideration that OCB tags are allowed to be truncated
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// to a length less than ocb.TagSize).
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//
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// The block cipher used in function must work on a block size equal to ocb2.BlockSize.
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// The tag slice used in this function must have a length equal to ocb2.TagSize.
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// The nonce slice used in this function must have a length equal to ocb2.NonceSize.
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// If any of the above are violated, Encrypt will panic.
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func Decrypt(cipher cipher.Block, plain []byte, encrypted []byte, nonce []byte, tag []byte) {
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if cipher.BlockSize() != BlockSize {
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panic("ocb2: cipher blocksize is not equal to ocb2.BlockSize")
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}
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if len(nonce) != NonceSize {
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panic("ocb2: nonce length is not equal to ocb2.NonceSize")
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}
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if len(tag) != TagSize {
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panic("ocb2: tag length is not equal to ocb2.TagSize")
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}
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var (
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checksum [BlockSize]byte
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delta [BlockSize]byte
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tmp [BlockSize]byte
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pad [BlockSize]byte
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off int
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)
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cipher.Encrypt(delta[0:], nonce[0:])
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zeros(checksum[0:])
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remain := len(encrypted)
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for remain > BlockSize {
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times2(delta[0:])
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xor(tmp[0:], delta[0:], encrypted[off:off+BlockSize])
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cipher.Decrypt(tmp[0:], tmp[0:])
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xor(plain[off:off+BlockSize], delta[0:], tmp[0:])
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xor(checksum[0:], checksum[0:], plain[off:off+BlockSize])
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off += BlockSize
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remain -= BlockSize
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}
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times2(delta[0:])
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zeros(tmp[0:])
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num := remain * 8
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tmp[BlockSize-2] = uint8((uint32(num) >> 8) & 0xff)
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tmp[BlockSize-1] = uint8(num & 0xff)
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xor(tmp[0:], tmp[0:], delta[0:])
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cipher.Encrypt(pad[0:], tmp[0:])
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zeros(tmp[0:])
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copied := copy(tmp[0:remain], encrypted[off:off+remain])
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if copied != remain {
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panic("ocb2: copy failed")
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}
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xor(tmp[0:], tmp[0:], pad[0:])
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xor(checksum[0:], checksum[0:], tmp[0:])
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copied = copy(plain[off:off+remain], tmp[0:remain])
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if copied != remain {
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panic("ocb2: copy failed")
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}
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times3(delta[0:])
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xor(tmp[0:], delta[0:], checksum[0:])
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cipher.Encrypt(tag[0:], tmp[0:])
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}
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// Copyright (c) 2010-2012 The Grumble Authors
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// The use of this source code is goverened by a BSD-style
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// license that can be found in the LICENSE-file.
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// Package ocb2 implements the version 2 of the OCB authenticated-encryption algorithm.
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// OCB2 is specified in http://www.cs.ucdavis.edu/~rogaway/papers/draft-krovetz-ocb-00.txt.
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//
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// Note that this implementation is limited to block ciphers with a block size of 128 bits.
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//
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// It should also be noted that OCB's author, Phil Rogaway <rogaway@cs.ucdavis.edu>, holds
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// several US patents on the algorithm. This should be considered before using this code
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// in your own projects. See OCB's FAQ for more info:
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// http://www.cs.ucdavis.edu/~rogaway/ocb/ocb-faq.htm#patent:phil
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//
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// The Mumble Project has a license to use OCB mode in its BSD licensed code on a royalty
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// free basis.
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package ocb2
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import (
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"crypto/cipher"
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"crypto/subtle"
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)
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const (
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// BlockSize defines the block size that this particular implementation
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// of OCB2 is made to work on.
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BlockSize = 16
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// TagSize specifies the length in bytes of a full OCB2 tag.
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// As per the specification, applications may truncate their
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// tags to a given length, but advocates that typical applications
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// should use a tag length of at least 8 bytes (64 bits).
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TagSize = BlockSize
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// NonceSize specifies the length in bytes of an OCB2 nonce.
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NonceSize = BlockSize
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)
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// zeros fills block with zero bytes.
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func zeros(block []byte) {
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for i := range block {
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block[i] = 0
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}
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}
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// xor outputs the bitwise exclusive-or of a and b to dst.
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func xor(dst []byte, a []byte, b []byte) {
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for i := 0; i < BlockSize; i++ {
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dst[i] = a[i] ^ b[i]
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}
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}
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// times2 performs the times2 operation, defined as:
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//
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// times2(S)
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// S << 1 if S[1] = 0, and (S << 1) xor const(bitlength(S)) if S[1] = 1.
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//
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// where const(n) is defined as
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//
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// const(n)
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// The lexicographically first n-bit string C among all
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// strings that have a minimal possible number of "1"
|
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// bits and which name a polynomial x^n + C[1] *
|
||||
// x^{n-1} + ... + C[n-1] * x^1 + C[n] * x^0 that is
|
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// irreducible over the field with two elements. In
|
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// particular, const(128) = num2str(135, 128). For
|
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// other values of n, refer to a standard table of
|
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// irreducible polynomials [G. Seroussi,
|
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// "Table of low-weight binary irreducible polynomials",
|
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// HP Labs Technical Report HPL-98-135, 1998.].
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//
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// and num2str(x, n) is defined as
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//
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// num2str(x, n)
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// The n-bit binary representation of the integer x.
|
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// More formally, the n-bit string S where x = S[1] *
|
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// 2^{n-1} + S[2] * 2^{n-2} + ... + S[n] * 2^{0}. Only
|
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// used when 0 <= x < 2^n.
|
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//
|
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// For our 128-bit block size implementation, this means that
|
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// the xor with const(bitlength(S)) if S[1] = 1 is implemented
|
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// by simply xor'ing the last byte with the number 135 when
|
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// S[1] = 1.
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func times2(block []byte) {
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carry := (block[0] >> 7) & 0x1
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for i := 0; i < BlockSize-1; i++ {
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block[i] = (block[i] << 1) | ((block[i+1] >> 7) & 0x1)
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}
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block[BlockSize-1] = (block[BlockSize-1] << 1) ^ (carry * 135)
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}
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// times3 performs the times3 operation, defined as:
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//
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// times3(S)
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// times2(S) xor S
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func times3(block []byte) {
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carry := (block[0] >> 7) & 0x1
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for i := 0; i < BlockSize-1; i++ {
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block[i] ^= (block[i] << 1) | ((block[i+1] >> 7) & 0x1)
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}
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block[BlockSize-1] ^= ((block[BlockSize-1] << 1) ^ (carry * 135))
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}
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// Encrypt encrypts the plaintext src and outputs the corresponding ciphertext into dst.
|
||||
// Besides outputting a ciphertext into dst, Encrypt also outputs an authentication tag
|
||||
// of ocb2.TagSize bytes into tag, which should be used to verify the authenticity of the
|
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// message on the receiving side.
|
||||
//
|
||||
// To ensure both authenticity and secrecy of messages, each invocation to this function must
|
||||
// be given an unique nonce of ocb2.NonceSize bytes. The nonce need not be secret (it can be
|
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// a counter), but it needs to be unique.
|
||||
//
|
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// The block cipher used in function must work on a block size equal to ocb2.BlockSize.
|
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// The tag slice used in this function must have a length equal to ocb2.TagSize.
|
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// The nonce slice used in this function must have a length equal to ocb2.NonceSize.
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// If any of the above are violated, Encrypt will panic.
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func Encrypt(cipher cipher.Block, dst []byte, src []byte, nonce []byte, tag []byte) {
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if cipher.BlockSize() != BlockSize {
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panic("ocb2: cipher blocksize is not equal to ocb2.BlockSize")
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}
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if len(nonce) != NonceSize {
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panic("ocb2: nonce length is not equal to ocb2.NonceSize")
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}
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if len(tag) != TagSize {
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panic("ocb2: tag length is not equal to ocb2.TagSize")
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}
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var (
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checksum [BlockSize]byte
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delta [BlockSize]byte
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tmp [BlockSize]byte
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pad [BlockSize]byte
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off int
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)
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cipher.Encrypt(delta[0:], nonce[0:])
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zeros(checksum[0:])
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remain := len(src)
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for remain > BlockSize {
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times2(delta[0:])
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xor(tmp[0:], delta[0:], src[off:off+BlockSize])
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cipher.Encrypt(tmp[0:], tmp[0:])
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xor(dst[off:off+BlockSize], delta[0:], tmp[0:])
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xor(checksum[0:], checksum[0:], src[off:off+BlockSize])
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remain -= BlockSize
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off += BlockSize
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}
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times2(delta[0:])
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zeros(tmp[0:])
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num := remain * 8
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tmp[BlockSize-2] = uint8((uint32(num) >> 8) & 0xff)
|
||||
tmp[BlockSize-1] = uint8(num & 0xff)
|
||||
xor(tmp[0:], tmp[0:], delta[0:])
|
||||
cipher.Encrypt(pad[0:], tmp[0:])
|
||||
copied := copy(tmp[0:], src[off:])
|
||||
if copied != remain {
|
||||
panic("ocb2: copy failed")
|
||||
}
|
||||
if copy(tmp[copied:], pad[copied:]) != (BlockSize - remain) {
|
||||
panic("ocb2: copy failed")
|
||||
}
|
||||
xor(checksum[0:], checksum[0:], tmp[0:])
|
||||
xor(tmp[0:], pad[0:], tmp[0:])
|
||||
if copy(dst[off:], tmp[0:]) != remain {
|
||||
panic("ocb2: copy failed")
|
||||
}
|
||||
|
||||
times3(delta[0:])
|
||||
xor(tmp[0:], delta[0:], checksum[0:])
|
||||
cipher.Encrypt(tag[0:], tmp[0:])
|
||||
}
|
||||
|
||||
// Decrypt takes a ciphertext, a nonce, and a tag as its input and outputs a decrypted
|
||||
// plaintext (if successful) and a boolean flag that determines whether the function
|
||||
// successfully decrypted the given ciphertext.
|
||||
//
|
||||
// Before using the decrpyted plaintext, the application
|
||||
// should verify that the computed authentication tag matches the tag that was produced when
|
||||
// encrypting the message (taking into consideration that OCB tags are allowed to be truncated
|
||||
// to a length less than ocb.TagSize).
|
||||
//
|
||||
// The block cipher used in function must work on a block size equal to ocb2.BlockSize.
|
||||
// The tag slice used in this function must have a length equal to ocb2.TagSize.
|
||||
// The nonce slice used in this function must have a length equal to ocb2.NonceSize.
|
||||
// If any of the above are violated, Encrypt will panic.
|
||||
func Decrypt(cipher cipher.Block, plain []byte, encrypted []byte, nonce []byte, tag []byte) bool {
|
||||
if cipher.BlockSize() != BlockSize {
|
||||
panic("ocb2: cipher blocksize is not equal to ocb2.BlockSize")
|
||||
}
|
||||
if len(nonce) != NonceSize {
|
||||
panic("ocb2: nonce length is not equal to ocb2.NonceSize")
|
||||
}
|
||||
|
||||
var (
|
||||
checksum [BlockSize]byte
|
||||
delta [BlockSize]byte
|
||||
tmp [BlockSize]byte
|
||||
pad [BlockSize]byte
|
||||
calcTag [NonceSize]byte
|
||||
off int
|
||||
)
|
||||
|
||||
cipher.Encrypt(delta[0:], nonce[0:])
|
||||
zeros(checksum[0:])
|
||||
|
||||
remain := len(encrypted)
|
||||
for remain > BlockSize {
|
||||
times2(delta[0:])
|
||||
xor(tmp[0:], delta[0:], encrypted[off:off+BlockSize])
|
||||
cipher.Decrypt(tmp[0:], tmp[0:])
|
||||
xor(plain[off:off+BlockSize], delta[0:], tmp[0:])
|
||||
xor(checksum[0:], checksum[0:], plain[off:off+BlockSize])
|
||||
off += BlockSize
|
||||
remain -= BlockSize
|
||||
}
|
||||
|
||||
times2(delta[0:])
|
||||
zeros(tmp[0:])
|
||||
num := remain * 8
|
||||
tmp[BlockSize-2] = uint8((uint32(num) >> 8) & 0xff)
|
||||
tmp[BlockSize-1] = uint8(num & 0xff)
|
||||
xor(tmp[0:], tmp[0:], delta[0:])
|
||||
cipher.Encrypt(pad[0:], tmp[0:])
|
||||
zeros(tmp[0:])
|
||||
copied := copy(tmp[0:remain], encrypted[off:off+remain])
|
||||
if copied != remain {
|
||||
panic("ocb2: copy failed")
|
||||
}
|
||||
xor(tmp[0:], tmp[0:], pad[0:])
|
||||
xor(checksum[0:], checksum[0:], tmp[0:])
|
||||
copied = copy(plain[off:off+remain], tmp[0:remain])
|
||||
if copied != remain {
|
||||
panic("ocb2: copy failed")
|
||||
}
|
||||
|
||||
times3(delta[0:])
|
||||
xor(tmp[0:], delta[0:], checksum[0:])
|
||||
cipher.Encrypt(calcTag[0:], tmp[0:])
|
||||
|
||||
// Compare the calculated tag with the expected tag. Truncate
|
||||
// the computed tag if necessary.
|
||||
if subtle.ConstantTimeCompare(calcTag[:len(tag)], tag) != 1 {
|
||||
return false
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
|
|
|
|||
|
|
@ -1,205 +1,201 @@
|
|||
// Copyright (c) 2010-2012 The Grumble Authors
|
||||
// The use of this source code is goverened by a BSD-style
|
||||
// license that can be found in the LICENSE-file.
|
||||
|
||||
package ocb2
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/aes"
|
||||
"encoding/hex"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func MustDecodeHex(s string) []byte {
|
||||
buf, err := hex.DecodeString(s)
|
||||
if err != nil {
|
||||
panic("MustDecodeHex: " + err.Error())
|
||||
}
|
||||
return buf
|
||||
}
|
||||
|
||||
type ocbVector struct {
|
||||
Name string
|
||||
Key string
|
||||
Nonce string
|
||||
Header string
|
||||
PlainText string
|
||||
CipherText string
|
||||
Tag string
|
||||
}
|
||||
|
||||
func (v ocbVector) KeyBytes() []byte {
|
||||
return MustDecodeHex(v.Key)
|
||||
}
|
||||
|
||||
func (v ocbVector) NonceBytes() []byte {
|
||||
return MustDecodeHex(v.Nonce)
|
||||
}
|
||||
|
||||
func (v ocbVector) PlainTextBytes() []byte {
|
||||
return MustDecodeHex(v.PlainText)
|
||||
}
|
||||
|
||||
func (v ocbVector) CipherTextBytes() []byte {
|
||||
return MustDecodeHex(v.CipherText)
|
||||
}
|
||||
|
||||
func (v ocbVector) TagBytes() []byte {
|
||||
return MustDecodeHex(v.Tag)
|
||||
}
|
||||
|
||||
// ocb128Vectors are the test vectors for OCB-AES128 from
|
||||
// http://www.cs.ucdavis.edu/~rogaway/papers/draft-krovetz-ocb-00.txt
|
||||
//
|
||||
// Note: currently, the vectors with headers are not included in this list
|
||||
// as this implementation does not implement header authentication.
|
||||
var ocb128Vectors = []ocbVector{
|
||||
{
|
||||
Name: "OCB2-AES-128-001",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "",
|
||||
CipherText: "",
|
||||
Tag: "BF3108130773AD5EC70EC69E7875A7B0",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-002",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "0001020304050607",
|
||||
CipherText: "C636B3A868F429BB",
|
||||
Tag: "A45F5FDEA5C088D1D7C8BE37CABC8C5C",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-003",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "000102030405060708090A0B0C0D0E0F",
|
||||
CipherText: "52E48F5D19FE2D9869F0C4A4B3D2BE57",
|
||||
Tag: "F7EE49AE7AA5B5E6645DB6B3966136F9",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-003",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "000102030405060708090A0B0C0D0E0F1011121314151617",
|
||||
CipherText: "F75D6BC8B4DC8D66B836A2B08B32A636CC579E145D323BEB",
|
||||
Tag: "A1A50F822819D6E0A216784AC24AC84C",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-004",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F",
|
||||
CipherText: "F75D6BC8B4DC8D66B836A2B08B32A636CEC3C555037571709DA25E1BB0421A27",
|
||||
Tag: "09CA6C73F0B5C6C5FD587122D75F2AA3",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-005",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F2021222324252627",
|
||||
CipherText: "F75D6BC8B4DC8D66B836A2B08B32A6369F1CD3C5228D79FD6C267F5F6AA7B231C7DFB9D59951AE9C",
|
||||
Tag: "9DB0CDF880F73E3E10D4EB3217766688",
|
||||
},
|
||||
}
|
||||
|
||||
func TestTimes2(t *testing.T) {
|
||||
msg := [aes.BlockSize]byte{
|
||||
0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe,
|
||||
}
|
||||
expected := [aes.BlockSize]byte{
|
||||
0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7b,
|
||||
}
|
||||
|
||||
times2(msg[0:])
|
||||
if !bytes.Equal(msg[0:], expected[0:]) {
|
||||
t.Fatalf("times2 produces invalid output: %v, expected: %v", msg, expected)
|
||||
}
|
||||
}
|
||||
|
||||
func TestTimes3(t *testing.T) {
|
||||
msg := [aes.BlockSize]byte{
|
||||
0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe,
|
||||
}
|
||||
expected := [aes.BlockSize]byte{
|
||||
0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x85,
|
||||
}
|
||||
|
||||
times3(msg[0:])
|
||||
if !bytes.Equal(msg[0:], expected[0:]) {
|
||||
t.Errorf("times3 produces invalid output: %v, expected: %v", msg, expected)
|
||||
}
|
||||
}
|
||||
|
||||
func TestZeros(t *testing.T) {
|
||||
var msg [aes.BlockSize]byte
|
||||
zeros(msg[0:])
|
||||
for i := 0; i < len(msg); i++ {
|
||||
if msg[i] != 0 {
|
||||
t.Fatalf("zeros does not zero slice.")
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestXor(t *testing.T) {
|
||||
msg := [aes.BlockSize]byte{
|
||||
0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe,
|
||||
}
|
||||
var out [aes.BlockSize]byte
|
||||
xor(out[0:], msg[0:], msg[0:])
|
||||
for i := 0; i < len(out); i++ {
|
||||
if out[i] != 0 {
|
||||
t.Fatalf("XOR broken")
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestEncryptOCBAES128Vectors(t *testing.T) {
|
||||
for _, vector := range ocb128Vectors {
|
||||
cipher, err := aes.NewCipher(vector.KeyBytes())
|
||||
if err != nil {
|
||||
t.Fatalf("%v", err)
|
||||
}
|
||||
|
||||
plainText := vector.PlainTextBytes()
|
||||
cipherText := make([]byte, len(plainText))
|
||||
tag := make([]byte, TagSize)
|
||||
Encrypt(cipher, cipherText, plainText, vector.NonceBytes(), tag)
|
||||
|
||||
expectedCipherText := vector.CipherTextBytes()
|
||||
if !bytes.Equal(cipherText, expectedCipherText) {
|
||||
t.Fatalf("expected CipherText %#v, got %#v", expectedCipherText, cipherText)
|
||||
}
|
||||
|
||||
expectedTag := vector.TagBytes()
|
||||
if !bytes.Equal(tag, expectedTag) {
|
||||
t.Fatalf("expected tag %#v, got %#v", expectedTag, tag)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestDecryptOCBAES128Vectors(t *testing.T) {
|
||||
for _, vector := range ocb128Vectors {
|
||||
cipher, err := aes.NewCipher(vector.KeyBytes())
|
||||
if err != nil {
|
||||
t.Fatalf("%v", err)
|
||||
}
|
||||
|
||||
cipherText := vector.CipherTextBytes()
|
||||
plainText := make([]byte, len(cipherText))
|
||||
tag := make([]byte, TagSize)
|
||||
Decrypt(cipher, plainText, cipherText, vector.NonceBytes(), tag)
|
||||
|
||||
expectedPlainText := vector.PlainTextBytes()
|
||||
if !bytes.Equal(plainText, expectedPlainText) {
|
||||
t.Fatalf("expected PlainText %#v, got %#v", expectedPlainText, plainText)
|
||||
}
|
||||
|
||||
expectedTag := vector.TagBytes()
|
||||
if !bytes.Equal(tag, expectedTag) {
|
||||
t.Fatalf("expected tag %#v, got %#v", expectedTag, tag)
|
||||
}
|
||||
}
|
||||
}
|
||||
// Copyright (c) 2010-2012 The Grumble Authors
|
||||
// The use of this source code is goverened by a BSD-style
|
||||
// license that can be found in the LICENSE-file.
|
||||
|
||||
package ocb2
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/aes"
|
||||
"encoding/hex"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func MustDecodeHex(s string) []byte {
|
||||
buf, err := hex.DecodeString(s)
|
||||
if err != nil {
|
||||
panic("MustDecodeHex: " + err.Error())
|
||||
}
|
||||
return buf
|
||||
}
|
||||
|
||||
type ocbVector struct {
|
||||
Name string
|
||||
Key string
|
||||
Nonce string
|
||||
Header string
|
||||
PlainText string
|
||||
CipherText string
|
||||
Tag string
|
||||
}
|
||||
|
||||
func (v ocbVector) KeyBytes() []byte {
|
||||
return MustDecodeHex(v.Key)
|
||||
}
|
||||
|
||||
func (v ocbVector) NonceBytes() []byte {
|
||||
return MustDecodeHex(v.Nonce)
|
||||
}
|
||||
|
||||
func (v ocbVector) PlainTextBytes() []byte {
|
||||
return MustDecodeHex(v.PlainText)
|
||||
}
|
||||
|
||||
func (v ocbVector) CipherTextBytes() []byte {
|
||||
return MustDecodeHex(v.CipherText)
|
||||
}
|
||||
|
||||
func (v ocbVector) TagBytes() []byte {
|
||||
return MustDecodeHex(v.Tag)
|
||||
}
|
||||
|
||||
// ocb128Vectors are the test vectors for OCB-AES128 from
|
||||
// http://www.cs.ucdavis.edu/~rogaway/papers/draft-krovetz-ocb-00.txt
|
||||
//
|
||||
// Note: currently, the vectors with headers are not included in this list
|
||||
// as this implementation does not implement header authentication.
|
||||
var ocb128Vectors = []ocbVector{
|
||||
{
|
||||
Name: "OCB2-AES-128-001",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "",
|
||||
CipherText: "",
|
||||
Tag: "BF3108130773AD5EC70EC69E7875A7B0",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-002",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "0001020304050607",
|
||||
CipherText: "C636B3A868F429BB",
|
||||
Tag: "A45F5FDEA5C088D1D7C8BE37CABC8C5C",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-003",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "000102030405060708090A0B0C0D0E0F",
|
||||
CipherText: "52E48F5D19FE2D9869F0C4A4B3D2BE57",
|
||||
Tag: "F7EE49AE7AA5B5E6645DB6B3966136F9",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-003",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "000102030405060708090A0B0C0D0E0F1011121314151617",
|
||||
CipherText: "F75D6BC8B4DC8D66B836A2B08B32A636CC579E145D323BEB",
|
||||
Tag: "A1A50F822819D6E0A216784AC24AC84C",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-004",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F",
|
||||
CipherText: "F75D6BC8B4DC8D66B836A2B08B32A636CEC3C555037571709DA25E1BB0421A27",
|
||||
Tag: "09CA6C73F0B5C6C5FD587122D75F2AA3",
|
||||
},
|
||||
{
|
||||
Name: "OCB2-AES-128-005",
|
||||
Key: "000102030405060708090A0B0C0D0E0F",
|
||||
Nonce: "000102030405060708090A0B0C0D0E0F",
|
||||
PlainText: "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F2021222324252627",
|
||||
CipherText: "F75D6BC8B4DC8D66B836A2B08B32A6369F1CD3C5228D79FD6C267F5F6AA7B231C7DFB9D59951AE9C",
|
||||
Tag: "9DB0CDF880F73E3E10D4EB3217766688",
|
||||
},
|
||||
}
|
||||
|
||||
func TestTimes2(t *testing.T) {
|
||||
msg := [aes.BlockSize]byte{
|
||||
0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe,
|
||||
}
|
||||
expected := [aes.BlockSize]byte{
|
||||
0x01, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7b,
|
||||
}
|
||||
|
||||
times2(msg[0:])
|
||||
if !bytes.Equal(msg[0:], expected[0:]) {
|
||||
t.Fatalf("times2 produces invalid output: %v, expected: %v", msg, expected)
|
||||
}
|
||||
}
|
||||
|
||||
func TestTimes3(t *testing.T) {
|
||||
msg := [aes.BlockSize]byte{
|
||||
0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe,
|
||||
}
|
||||
expected := [aes.BlockSize]byte{
|
||||
0x81, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x85,
|
||||
}
|
||||
|
||||
times3(msg[0:])
|
||||
if !bytes.Equal(msg[0:], expected[0:]) {
|
||||
t.Errorf("times3 produces invalid output: %v, expected: %v", msg, expected)
|
||||
}
|
||||
}
|
||||
|
||||
func TestZeros(t *testing.T) {
|
||||
var msg [aes.BlockSize]byte
|
||||
zeros(msg[0:])
|
||||
for i := 0; i < len(msg); i++ {
|
||||
if msg[i] != 0 {
|
||||
t.Fatalf("zeros does not zero slice.")
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestXor(t *testing.T) {
|
||||
msg := [aes.BlockSize]byte{
|
||||
0x80, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe,
|
||||
}
|
||||
var out [aes.BlockSize]byte
|
||||
xor(out[0:], msg[0:], msg[0:])
|
||||
for i := 0; i < len(out); i++ {
|
||||
if out[i] != 0 {
|
||||
t.Fatalf("XOR broken")
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestEncryptOCBAES128Vectors(t *testing.T) {
|
||||
for _, vector := range ocb128Vectors {
|
||||
cipher, err := aes.NewCipher(vector.KeyBytes())
|
||||
if err != nil {
|
||||
t.Fatalf("%v", err)
|
||||
}
|
||||
|
||||
plainText := vector.PlainTextBytes()
|
||||
cipherText := make([]byte, len(plainText))
|
||||
tag := make([]byte, TagSize)
|
||||
Encrypt(cipher, cipherText, plainText, vector.NonceBytes(), tag)
|
||||
|
||||
expectedCipherText := vector.CipherTextBytes()
|
||||
if !bytes.Equal(cipherText, expectedCipherText) {
|
||||
t.Fatalf("expected CipherText %#v, got %#v", expectedCipherText, cipherText)
|
||||
}
|
||||
|
||||
expectedTag := vector.TagBytes()
|
||||
if !bytes.Equal(tag, expectedTag) {
|
||||
t.Fatalf("expected tag %#v, got %#v", expectedTag, tag)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
func TestDecryptOCBAES128Vectors(t *testing.T) {
|
||||
for _, vector := range ocb128Vectors {
|
||||
cipher, err := aes.NewCipher(vector.KeyBytes())
|
||||
if err != nil {
|
||||
t.Fatalf("%v", err)
|
||||
}
|
||||
|
||||
cipherText := vector.CipherTextBytes()
|
||||
plainText := make([]byte, len(cipherText))
|
||||
if Decrypt(cipher, plainText, cipherText, vector.NonceBytes(), vector.TagBytes()) == false {
|
||||
t.Fatalf("expected decrypt success; got failure. tag mismatch?")
|
||||
}
|
||||
|
||||
expectedPlainText := vector.PlainTextBytes()
|
||||
if !bytes.Equal(plainText, expectedPlainText) {
|
||||
t.Fatalf("expected PlainText %#v, got %#v", expectedPlainText, plainText)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue