Network Security: Lab#4-1 Security J. H. Wang Dec. 3, 2013
Objectives To learn to use security tools –PGP To learn the availability of security libraries –S/MIME –DKIM
Packages & Libraries in this Lab Packages –GPG4win: for Windows Libraries –OpenDKIM
Experiment Scenario Signing/verification of files using certificates –Create a new certificate –Encrypt/sign the file “original.txt” into another file “enc.txt” (using sender’s certificate) –Then, we decrypt/verify it and get another file “dec.txt” (using sender’s certificate), and check if the decrypted file is the same as the original file Sending/receiving s with certificates –Set up account –Read mails –Send mails
GnuPG Privacy Guard Homepage: Version: – (portable standalone version) – (enhanced version, harder to build) Platforms: Linux/FreeBSD/Windows/MacOS X An implementation of OpenPGP Installation steps –(skipped)
GPG4win Homepage: Latest version: OpenPGP: an open standard for security (RFC 4880) –S/MIME also included Installation steps: –Simply follow the instructions on screen
Other Tools Included in GPG4win Kleopatra: GnuPG certificate manager –New certificate –Encrypting/Signing a file –Decrypting/Verifying a file Claws Mail: a mail reader –Setting up your mail account –Reading mails –Sending mails
Microsoft Outlook Support in GPG4win PGP for Outlook –GpgOL 1.0 can support OpenPGP and S/MIME
Configuring Outlook for S/MIME Configure Your Personal Certificates Send a Signed Message Read a Signed Message Check the Credentials of a Signed Message Send an Encrypted Message Read an Encrypted Message Get Certificates for Other Users
OpenDKIM Homepage: –Latest version: opendkim –C library for DKIM service: libmilter –Also a milter-based filter application: opendkim Can plug in to any milter-based MTAs: Sendmail, PostFix An open source implementation for IETF DKIM standard (RFC 6376) based on dkim-milter from Sendmail –Library: libdkim –Milter: dkim-milter (plugins to sendmail) Also includes implementations of –ADSP (Author Domain Signing Practises): RFC 5617 –VBR (Vouch by Reference): RFC 5518
Configuration and Installation Compilation of opendkim –Download opendkim tar.gz – tar -xzvf opendkim tar.gz – cd opendkim –./configure – make – make install Configuration of opendkim –For signing and verification Install opendkim and configure your MTA
Summary security –PGP –S/MIME –DKIM