diff options
Diffstat (limited to 'doc/source/crypto/fhmqvc.rst')
| -rw-r--r-- | doc/source/crypto/fhmqvc.rst | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/doc/source/crypto/fhmqvc.rst b/doc/source/crypto/fhmqvc.rst index aa6f0cc..e3af6d4 100644 --- a/doc/source/crypto/fhmqvc.rst +++ b/doc/source/crypto/fhmqvc.rst @@ -75,11 +75,9 @@ following definitions for these functions: .. math:: - \begin{align} - d|e &= \text{SHA256}(Y|X|\hat{B}|\hat{A}) \\ - K_1 &= \textit{KDF}_1(\sigma,\hat{A},\hat{B},X,Y) = \text{HKDF-SHA256}(\texttt{0x00}^{32}, \sigma, \hat{A}|\hat{B}|X|Y, 32) \\ - K_2 &= \textit{KDF}_2(\sigma,\hat{A},\hat{B},X,Y) = \text{HKDF-SHA256}(K_1, \sigma, \hat{A}|\hat{B}|X|Y|\textit{method}, *) - \end{align} + d|e &= \text{SHA256}(Y|X|\hat{B}|\hat{A}) \\ + K_1 &= \textit{KDF}_1(\sigma,\hat{A},\hat{B},X,Y) = \text{HKDF-SHA256}(\texttt{0x00}^{32}, \sigma, \hat{A}|\hat{B}|X|Y, 32) \\ + K_2 &= \textit{KDF}_2(\sigma,\hat{A},\hat{B},X,Y) = \text{HKDF-SHA256}(K_1, \sigma, \hat{A}|\hat{B}|X|Y|\textit{method}, *) where :math:`V|W` designates the concatenation of the binary strings :math:`V` and :math:`W` and @@ -96,10 +94,8 @@ as .. math:: - \begin{align} - d = \bar{H}(X|Y|\hat{A}|\hat{B}) \\ - e = \bar{H}(Y|X|\hat{A}|\hat{B}) - \end{align} + d &= \bar{H}(X|Y|\hat{A}|\hat{B}) \\ + e &= \bar{H}(Y|X|\hat{A}|\hat{B}) fastd uses a single 256 bit hash :math:`\text{SHA256}(Y|X|\hat{B}|\hat{A})` instead and cuts it into two 128 bit pieces which are used as :math:`d` and :math:`e`. This optimization allows reusing the SHA256 implementation that is already used for |