DH

Diffie-Hellman video

DH

spec

Description: Public-key cryptosystem

Problem: Discrete logarithm problem

Uses: Key exchange

How to ???

#!/usr/bin/env python

import requests
import json
import os,binascii

def sending(message):
    url = 'http://127.0.0.1:6613/'
    response = requests.post(url, data=message)
    print response.content
    return response.content

def dh(data_js):
    req=json.loads(data_js)
    print "Send gen parameters (A): \n " + json.dumps(req) +"\n"
    data_js_n=sending(json.dumps(req))
    answ=json.loads(data_js_n)
    print "Recived gen parameters donde (A): \n" + (json.dumps(answ)) +"\n\n\n"
    data_js_n=sending(json.dumps(req))
    print "Send gen parameters (B): \n " + json.dumps(req) +"\n"
    answ_1=json.loads(data_js_n)
    print "Recived gen parameters donde (B): \n" + (json.dumps(answ_1)) +"\n\n\n"
    gen='{ "version":1 , "algorithm":"DH","family": "", "privkey":"","sharedpub":"", "operation":"a_rfc"}'
    req=json.loads(gen)
    req["family"]=answ["family"]
    req["privkey"]=answ["privkey"]
    req["sharedpub"]=answ_1["pubkey"]
    print "Send agreetment (A): \n " + json.dumps(req) +"\n"
    data_js_n=sending(json.dumps(req))
    answ_2=json.loads(data_js_n)
    print "Recived agreetment donde (A): \n" + (json.dumps(answ_2)) +"\n\n\n"
    req["privkey"]=answ_1["privkey"]
    req["sharedpub"]=answ["pubkey"]
    print "Send agreetment (B): \n " + json.dumps(req) +"\n"
    data_js_n=sending(json.dumps(req))
    answ_3=json.loads(data_js_n)
    print "Recived agreetment donde (B): \n" + (json.dumps(answ_3)) +"\n\n\n"


dh_gen='{ "version": 1 , "algorithm":"DH", "family": "modp256", "operation":"gen_rfc"}'
dh(dh_gen)

In this example we generate keys for A and B, and we make a key exchange between A and B.

On "family" parameneter can be {"modp256","modp160","modp224"}

Json to gen

{ "version": 1 , "algorithm":"DH", "family": "mod flavor", "operation":"gen_rfc"}

Json to key agreetment

{ "version":1 , "algorithm":"DH","family": "mod flavor", "privkey":" your hex privkey",
"sharedpub":"your partnert hex pubkey", "operation":"a_rfc"}