Độc giả như mình đã nói với chúng tôi họ muốn một dịch vụ dựa trên Internet mà có thể mở rộng và nâng cao giá trị của các cuốn sách. Căn cứ vào đọc những phản hồi và kế hoạch chiến lược của chúng tôi, chúng tôi đã tạo ra một trang Web mà chúng tôi hy vọng sẽ vượt quá mong đợi của bạn. Solutions@ là một kho tàng tương tác của các thông tin hữu ích tập trung vào các chủ đề cuốn sách của chúng tôi và. | 36 Chapter 1 Introduction to Open Source Security 0 Before installing open source software make sure that your operating system contains all of the necessary supporting applications and libraries. Should I Use an RPM or Tarballs 0 RPMs sometimes offer convenience. However precompiled RPMs often do not have all of the features necessary to implement a truly useful product. 0 Tarballs often require editing of a special file called a makefile. However this is not necessarily all that difficult. It simply requires that you know where your supporting applications and libraries are. Also most open source software will contain instructions concerning how to edit the makefile. Most well-known operating systems such as Red Hat Linux and Slackware do not require makefile modification. 0 RPMs often contain useful startup scripts that are not found elsewhere. Sometimes it is useful to install the RPM then the tarball version and then combine elements from the two for a complete solution. Obtaining Open Source Software 0 Sites such as SourceForge RPMFind and SecurityFocus are valuable software sources. 0 Be especially careful when downloading any source code regardless of format. Digital signatures can help you determine the author of a package as well as whether a package has been altered. 4 0 The Gnu Privacy Guard GPG and Pretty Good Privacy PGP pack- ages are available to help you verify signatures. They do not stop the execution of malicious code however. They simply inform you about the nature of the code s author and of any changes that may have occurred to the code. Introduction to Open Source Security Chapter 1 37 A Brief Encryption Review 0 Symmetric encryption is the use of one key to encrypt and decrypt information. If a malicious user is able to intercept the key he or she can then use it to decrypt your secret messages. 0 Asymmetric encryption uses a mathematically related key pair to .
