book

BSD Hacks

by Dru Lavigne

May 2004

Intermediate to advanced

450 pages

12h 18m

English

O'Reilly Media, Inc.

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About the AuthorContributorsAcknowledgments
Why BSD Hacks?How to Use this BookHow This Book Is OrganizedConventions Used in This BookUsing Code ExamplesWe’d Like to Hear from You
Introduction1. Get the Most Out of the Default ShellHistory and Auto-CompletionEditing and Navigating the Command LineLearning from Your Command HistorySilencing Auto-CompleteSee Also2. Useful tcsh Shell Configuration File OptionsMaking Your Prompt More UsefulSetting Shell Variables3. Create Shell BindingsCreating a BindingSpecifying StringsSee Also4. Use Terminal and X BindingsCreating Temporary MappingsShell Bindings Versus Terminal BindingsMore Mapping CaveatsMaking Mappings Work with XSee Also5. Use the Mouse at a TerminalIf X Is Already InstalledConfiguring a two-button mouseIf X Is Not InstalledSee Also6. Get Your Daily Dose of TriviaA Fortune a DayPursuing TriviaSundry AmusementsThe current timeThe phase of the moonAdding Some Color to Your TerminalSee Also7. Lock the ScreenUsing lockUsing autologoutEnforcing LogoutSee Also8. Create a Trash DirectoryShell Scripting for the ImpatientThe CodeReplacing rm with ~/bin/trashRunning the Code SafelyTaking Out the TrashHacking the Hack9. Customize User ConfigurationsDefault Filesdot.cshrcdot.logindot.login_confdot.mail_aliases and dot.mailrcdot.profiledot.rhostsdot.shrcMissing (but Useful) Dot Filesdot.logoutdot.xinitrcEditing /usr/src/share/skel/MakefileThe Other BSDsNetBSDOpenBSDSee Also10. Maintain Your Environment on Multiple SystemsEnter unisonUsing unisonAutomating the ProcessCreating Portable FilesSee Also11. Use an Interactive ShellRecording All Shell Input and OutputCleaning Up script FilesRecording an Interactive Shell SessionLetting Other People Watch Your Live Shell SessionsSee Also12. Use Multiple Screens on One TerminalWhat Is screen?Getting StartedMultitasking with screenUsing windows with screenSwitching between windowsSplitting windowsBetter window switchingNaming windowsAttaching and DeattachingAdditional FeaturesSee Also
Introduction13. Find ThingsFinding Program PathsFinding CommandsFinding WordsSee Also14. Get the Most Out of grepFinding TextSearching by RelevanceDocument ExtractsUsing Regular ExpressionsCombining grep with Other CommandsSee Also15. Manipulate Files with sedRemoving Blank LinesSearching with sedReplacing Existing TextMultiple TransformationsSee Also16. Format Text at the Command LineAdding Comments to Source CodeRemoving CommentsUsing the Holding Space to Mark TextTranslating CaseTranslating CharactersRemoving Duplicate Line FeedsDeleting CharactersTranslating Tabs to SpacesSee Also17. Delimiter DilemmaAttacking the ProblemThe CodeHacking the HackSee Also18. DOS Floppy ManipulationMounting a FloppyCommon Error MessagesManaging the FloppyAllowing Regular Users to Mount FloppiesFormatting FloppiesAutomating the Format ProcessSee Also19. Access Windows Shares Without a ServerInstalling and Configuring Sharity-LightAccessing Microsoft SharesSee Also20. Deal with Disk HogsPeriodic Scriptsdaily_clean_disksdaily_clean_tmpsdaily_clean_preserveLimiting FilesThe Other BSDsNetBSDOpenBSDSee Also21. Manage Temporary Files and Swap SpaceClearing /tmpMoving /tmp to RAMCreating a Swap File on DiskMonitoring Swap ChangesOpenBSD DifferencesSee Also22. Recreate a Directory Structure Using mtreeNecessary InteractionUsing mtreeCustomizing mtreeSee Also23. Ghosting SystemsCreating the Ghost DiskCreating an ImageDeploying the ImageSee Also
Introduction24. Customize the Default Boot MenuThe Default Boot MenuConfiguring the Splash ScreenThe Terminal ScreensaverSee Also25. Protect the Boot ProcessLimiting Unauthorized RebootsPassword Protecting Single-User ModePassword Protecting loaderSee Also26. Run a Headless SystemPreparing the SystemIf the Headless System Becomes InaccessibleSee Also27. Log a Headless Server RemotelyEnabling a Serial ConsoleSetting Up the Logging ServerSetting Up the Headless SystemShutting Down the Server Using wsmousedBeep on HaltSee Also28. Remove the Terminal Login BannerChanging the Copyright DisplayChanging the Message of the DayChanging the Login PromptTesting Your ChangesSee Also29. Protecting Passwords With Blowfish HashesProtecting System Passwords in GeneralProtecting System Passwords with BlowfishConverting existing passwordsForcing new passwords to use BlowfishSee Also30. Monitor Password Policy ComplianceInstalling and Using crackMonitoring the resultsCleanupCustomizing Password DictionariesSee Also31. Create an Effective, Reusable Password PolicyIntroducing pam_passwdqcEnabling pam_passwdqcAdding Your Own OptionsAdditional ConfigurationSee Also32. Automate Memorable Password GenerationInstalling and Using apgImproving apgScript WalkthroughSee Also33. Use One Time PasswordsConfiguring OPIEGenerating ResponsesChoosing When to Use OTPSee Also34. Restrict Logins/etc/ttys/etc/login.access/etc/ssh/sshd_config/etc/login.confSee Also
Introduction35. Back Up FreeBSD with SMBFSAdding NETSMB Kernel SupportEstablishing an SMB Connection with a Host SystemMounting a ShareArchiving and Compressing Data with tar and gzipHacking the HackSee Also36. Create Portable POSIX ArchivesGNU Versus POSIX tarReplacing tar with paxCompress Archives Without Using Intermediate FilesAttribute-Preserving CopiesRooted Archives and the Substitution ArgumentUseful Resources for Multiple Volume ArchivesSee Also37. Interactive CopyFinding Your Source FilesRenaming a Batch of Source FilesRenaming Files InteractivelySee Also38. Secure Backups Over a NetworkInitial PreparationThe BackupAutomating the backupSee Also39. Automate Remote BackupsInstalling and Configuring rsnapshotSpecifying backup intervalsPreparing for script automationTesting your config fileScheduling rsnapshotThe Snapshot Storage SchemeAccessing SnapshotsSee Also40. Automate Data Dumps for PostgreSQL DatabasesCreating the ScriptThe CodeRunning the HackSee Also41. Perform Client-Server Cross-Platform Backups with BaculaIntroducing BaculaInstallationConfiguration FilesFile Daemon on the backup clientStorage Daemon on the backup serverDirector on the backup serverDatabase SetupTesting Your Tape DriveRunning Without RootStarting the Bacula DaemonsUsing the Bacula ConsoleCreating Backup SchedulesCreating a Client-only InstallSee Also
Introduction42. See Console Messages Over a Remote LoginThe ConsoleSeeing Remote Console MessagesAn Alternate MethodHacking the HackSee Also43. Spoof a MAC AddressSpoofing on FreeBSDSpoofing on NetBSDSpoofing with OpenBSDSee Also44. Use Multiple Wireless NIC ConfigurationsInitial PreparationPreparing the ScriptThe CodeRunning the HackHacking the HackSee Also45. Survive Catastrophic Internet LossHardware ConfigurationConnectivity SoftwareJabber and Ruby to the Rescue!The Last PieceSee Also46. Humanize tcpdump OutputThe BasicsDisplay FiltersMore Complicated FiltersDeciphering tcpdump OutputSee Also47. Understand DNS Records and ToolsExploring Your ISP’s DNSUnderstanding DNS entriesSecuring DNSThe two-pronged approachTesting DNSSee Also48. Send and Receive Email Without a Mail ClientSending Email with telnetTesting for RelayingTesting SMTP Server AvailabilityReading Email with telnetSecurity ConsiderationsSee Also49. Why Do I Need sendmail?Closing Port 25Simple sendmail Configuration with a Local MTASimple sendmail Configuration Without a Local MTASee Also50. Hold Email for Later DeliveryConfiguring sendmail QueueingConfiguring PPPDealing with DNSSee Also51. Get the Most Out of FTPAutomating LoginsAutomating TransfersScripting an Entire SessionA Better FTP?See Also52. Distributed Command ExecutionThe Obvious ApproachHow tentakel Can HelpInstalling and Configuring tentakelUsing tentakelSee Also53. Interactive Remote AdministrationWhy ClusterIt?Installation and ConfigurationTesting Noninteractive CommandsUsing dvtHacking the HackSee Also
Introduction54. Strip the KernelCustomizing Your KernelCPU optionsSystem-specific optionsSupported buses and media devicesPeripheral support and power managementInterface supportUSB supportBuilding the New KernelKeeping Track of Your OptionsInstalling the New KernelSee Also55. FreeBSD Access Control ListsEnabling ACLsAdditional UFS1 ConfigurationViewing ACLsAdding and Subtracting ACLsUsing ACLs with Samba and WindowsSetting Default ACLsSee Also56. Protect Files with FlagsPreventing File ChangesWatch Your DirectoriesPreventing Some Changes and Allowing OthersLog ProtectionProtecting BinariesControlling BackupsSee Also57. Tighten Security with Mandatory Access ControlPreparing the SystemSeeing Other UsersQuickly Disable All InterfacesSee Also58. Use mtree as a Built-in TripwireCreating the Integrity DatabasePreparing the Database for StorageUsing the Integrity DatabaseDeciding on Which Files to IncludeSee Also59. Intrusion Detection with Snort, ACID, MySQL, and FreeBSDInstalling the SoftwareInstall PHP4, Apache, and MySQLInstall MySQL-serverMore installationsConfiguringConfigure Apache and PHPConfigure PHPConfigure MySQLConfigure SnortConfigure ACIDRunning ACIDRunning SnortHacking the HackSee Also60. Encrypt Your Hard DiskThe Cryptographic Disk DevicePreparing the DiskScrubbing the DiskCreating the Encrypted Disk DeviceModifying Configuration FilesRestoring DataHacking the HackFinal Thoughts and WarningsSee Also61. Sudo GotchasLimitations of sudosudo Configuration GotchasShell Access with sudoSee Also62. sudoscriptsudoscript OverviewIs sudoscript Secure?Using sudoscriptThe sudoscript Log FileSee Also63. Restrict an SSH serverInstalling scponlyTesting the chrootNow What?See Also64. Script IP Filter RulesetsLimiting Access with IP FilterSwitching Rules on a ScheduleHacking the HackSee Also65. Secure a Wireless Network Using PFDHCP ConfigurationPF ConfigurationApache ConfigurationPutting it All TogetherSecurity ConcernsHacking the HackSee Also66. Automatically Generate Firewall RulesWhat the Script DoesInstallationExample UsageSee Also67. Automate Security PatchesPreparing the ScriptRunning the HackAutomating the ProcessSee Also68. Scan a Network of Windows Computers for VirusesPreparing the Windows SystemsPreparing the FreeBSD SystemInstalling and Running the Virus ScannerAutomating the ProcessSee Also
Introduction69. Tune FreeBSD for Different ApplicationsOptimizing Software CompilingKernel OptimizationsOptimizing Network PerformanceOptimizing Mail ServersOptimizing File ServersOptimizing Web ServersSee Also70. Traffic Shaping on FreeBSDConfiguring Your Kernel for Traffic ShapingCreating Pipes and QueuesUsing MasksSimple ConfigurationsComplex ConfigurationsSee Also71. Create an Emergency Repair KitInventory of the KitPreparing the FloppiesThe Rest of the KitTesting the Recovery MediaSee Also72. Use the FreeBSD Recovery ProcessUsing the fixit FloppyUsing the Live FilesystemEmergency RepairSee Also73. Use the GNU Debugger to Analyze a Buffer OverflowAn Example ExploitUsing the GNU DebuggerHacking the HackSee Also74. Consolidate Web Server Logslogproc DescribedPreparing the Web ServersPreparing the Log HostTesting the ConfigurationConfiguring Scripts on the Log HostViewing Live Log DataSee Also75. Script User InteractionThe Key Generation ProcessA Simple ScriptAdding User InteractionHandling Incorrect InputHacking the HackSee Also76. Create a Trade Show DemoIntroducing eeshDiscovering CommandsSample ScriptsMore Complex ScriptsSee Also

Introduction77. Automated InstallPreparing the Install ScriptTest-DriveSee Also78. FreeBSD from ScratchStage One: System InstallationStage Two: Ports InstallationStage Three: Post-ConfigurationSee Also79. Safely Merge Changes to /etcInitial PreparationsUsing etcmergeSee Also80. Automate UpdatesAssembling the PiecesAn Example Dry RunAutomating the ProcessSee Also81. Create a Package RepositoryCreating Custom PackagesCreating the NFS ShareSee Also82. Build a Port Without the Ports TreeConnecting to Anonymous CVSChecking Out Port SkeletonsFinding a Port and Its DependenciesSee Also83. Keep Ports Up-to-Date with CTMUsing ftp and ctm to Stay CurrentHacking the HackSee Also84. Navigate the Ports SystemFinding the Right PortDealing with Installed PortsChecking Dependencies Before UninstallingChecking the Disk Space Your Ports UseSee Also85. Downgrade a PortUsing portdowngradePreventing Automated Re-UpgradesSee Also86. Create Your Own Startup ScriptsWas a Script Installed?Creating Your Own Startup ScriptTesting the ScriptHacking the HackSee Also87. Automate NetBSD Package BuildsInstalling pkg_compConfiguration VariablesInitializing and Using the SandboxAutomating the ProcessHacking the HackSee Also88. Easily Install Unix Applications on Mac OS XInstalling DarwinPortsFinding Ports to InstallInstalling PortsUpdating the Ports TreeSee Also
Introduction89. How’d He Know That?Online ResourcesKeeping Offline Resources Up-to-DateWhat Did the Manpage Forget to Say?See Also90. Create Your Own ManpagesManpage BasicsCreating a ManpageGetting FancierPrinting ManpagesHacking the HackSee Also91. Get the Most Out of ManpagesFinding Installed ManpagesNavigational TricksCustomizing lessSearching TextSee Also92. Apply, Understand, and Create PatchesFinding DifferencesApplying PatchesCreating PatchesRevision ControlSee Also93. Display Hardware InformationViewing Boot MessagesViewing Resource InformationGathering Interface StatisticsViewing Kernel EnvironmentSee Also94. Determine Who Is on the SystemWho’s on First?When Did That Happen?Details, DetailsSee Also95. Spelling BeeQuick SpellcheckCreating a Dictionary or ThesaurusImproved DictionaryBecome a Crossword ChampionSee Also96. Leave on TimeDon’t Forget to LeaveCreating Terminal Sticky NotesSaving Your ScheduleSee Also97. Run Native Java ApplicationsChoosing Which Java Port to InstallRunning Java ApplicationsStandalone Java ApplicationsJavavmwrapperAppletsServletsJava WebStartSee Also98. Rotate Your SignatureIf Your Mail Program Supports a PipePipeless Signature RotationHacking the HackSee Also99. Useful One-LinersSimultaneously Download and UntarWhen Did I Change That File?Finding SymlinksMaking cron More User-FriendlySee Also100. Fun with XSeeing Console MessagesManaging Your ClipboardSending Pop-up MessagesUnderstanding X authorizationTaking ScreenshotsSee Also

Content preview from BSD Hacks

Index

A note on the digital index

A link in an index entry is displayed as the section title in which that entry appears. Because some sections have multiple index markers, it is not unusual for an entry to have several links to the same section. Clicking on any link will take you directly to the place in the text in which the marker appears.

Symbols

! (bang) character, retrieving previously issued commands, Learning from Your Command History
# (hash mark) for comments in code, The Default Boot Menu
(') (single quote) vs. backticks (`), Finding Program Paths
(`) (backticks) vs. single quote ('), Finding Program Paths
.\” (comment) groff command, Creating a Manpage