# 中文测试 中文測試 Chinese test

·172 words·1 min

123123

id：ljahum @Syclover

print(代码测试)


$$123123$$

$123$

$$123123$$

## Introduction (TL;DR) #

Authenticated encryption (AE) is a term used to describe encryption systems that simultaneously protect confidentiality and authenticity (integrity) of communications; that is, AE provides both message encryption and message authentication of a plaintext block or message .

The offset codebook block cipher mode (OCB)

OCB provide an extremely efficient algorithm, equal to or more efficient than other AE algorithms. OCB is a cipher mode and we can apply ocb to AES/DES/SM4 etc.

The following paragraph briefly introduces OCB1 and OCB2

## OCB1 #

Figure 1 shows the overall structure for OCB encryption and authentication.

The message M to be encrypted and authenticated is divided into n-bit blocks, with the exception of the last block, which may be less than n bits. Typically, n = 128.

enc

Input:$(N,M)$

Output:$(C,T)$

$$123123$$

$$sdfasdfasd$$

% KaTeX block notation $$\varphi = 1+\frac{1} {1+\frac{1} {1+\frac{1} {1+\cdots} } }$$

% KaTeX inline notation Inline notation: $$\varphi = \dfrac{1+\sqrt5}{2}= 1.6180339887…$$