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Man-in-the-Middle (MIM) attack to Diffie-Hellman (DH) Key Agreement Protocol (KAP)._{}^{}

COMPLETED.

Imagine You are an active eavesdropper Zoe and want to arrange Man-in-the-Middle (MIM) attack to Diffie-Hellman (DH) Key Agreement Protocol (KAP) between Alice and Bob which actions are simulated by the Mentor. Parameter values sent by Zoe to Mentor are entered in the input field and are included in brackets [ ] and must be entered in the corresponding input fields.

The following functions are used in the protocol:

**>> mod_exp(g,x,p)**

**>> randi(z)**

System parameters known for all parties are prime number ** p**=147146159 and generator

- Alice randomly generates secret number
in the interval*x***1<**. She computes public parameter*x*<*p*-1and sends*K*_{A}=g^{x }mod p=….. to Bob. An active eavesdropper Zoe intercepts*K*_{A}*K*_{A}in the interval*z*1**1<**, using function randi(2^25), computes public parameter*z*1<*p*-1and sends this number [*K*_{AZ}=g^{z}^{1 }*mod p*] to Alice.*K*_{AZ} - Analogously, to impersonate Alice, Zoe randomly generates secret key
in the interval*z*2**1<**, computes public parameter*z*2<*p*-1and sends [*K*=_{ZB}*g*^{z}^{2 }*mod p*] to Bob.*K*_{ZB} - Alice presuming that message containing
is received from Bob, computes the agreed secret key*K*_{AZ}.*K*_{1}=( K_{AZ})^{x}mod p - Bob presuming that message containing
is received from Alice, randomly generates secret number*K*_{ZB}in the interval*y***1**. He computes public parameter*<y<p*-1and sends*K*_{B}=g^{y }mod pto Alice. Then Bob computes the agreed secret key*K*_{B}, thinking that Alice has the same secret key. But Zoe intercepts*K*(_{2}=*K*)_{ZB}^{y}mod pand stops message transmission to Alice.*K*_{B} - Zoe computes secret keys
and*K*(_{Z1}=*K*)_{A}^{z1}mod p. Using modular mathematics she proves to herself that*K*(_{Z2}=*K*)_{B}^{z2}mod pand*K*_{Z1}= K_{1}.*K*_{Z2}= K_{2} - What does it means? How Zoe knows the content of all correspondence during the session?

7. You can test Yourself in arranging MIMDH attack with the following artificially small public parameters: ** p**=31 and

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