Design And Implementation Of OpensSSL Chat Tools

Live chat tool is increasingly becoming popular among modern people. Through it,one can easily and quickly communicate with others and share data. However,eavesdropping, tampering, counterfeiting and other identity threats in reality also existin the network. Therefore, to ensure information security increasingly becomeimportant.SSL protocol uses the combination of public key cryptography and symmetriccryptography to protect data confidentiality and integrity. The system first utilizessocket programming techniques to design the underlying message interaction, and thenuses OpenSSL to provide the tools to build a CA certificate, aims to support thecertificate management.Then using the OpenSSL API interface to establish the coreinformation transmission channel for SSL, implement secure message exchange model,to achieve data confidentiality, integrity protection, and to achieve the validation of datasources.Since the tool itself needs to provide chat and file transfer capabilities, due toensure the safety, the client and the server were need designed respectively, andmerging all the mentioned.Finally, using MFC visual interface design to provide afriendly, simple and easy to operate, highly interactive user interface.This dissertation briefly describes the use of secure communication open sourcelibrary OpenSSL programming interface to development chat tools.Tool featuresinclude building a CA-signed certificate, generating X.509certificate request; utilizingcertificate to establish an SSL peer information transmission channel andimplementing an SSL connection.Tool could transmit information securely, keepdata security.Finally running test results show that the cipher text data transmittedover SSL channel, confidentiality and integrity have been better protected.