KASPERSKY LAB Kaspersky® SMTP-Gateway 5.5 for Linux/Unix ADMINISTRATOR'S GUIDE KASPERSKY® SMTP-GATEWAY 5.5 FOR LINUX/UNIX Administrator's Guide © Kaspersky Lab http://www.kaspersky.com Revision date: July 2005 Contents CHAPTER 1. KASPERSKY® SMTP-GATEWAY 5.5 FOR LINUX/UNIX...................... 6 1.1. What's new in version 5.5 ..................................................................................... 7 1.2. Licensing policy ..................................................................................................... 8 1.3. Hardware and software requirements .................................................................. 8 1.4. Distribution kit ........................................................................................................ 9 1.5. Help desk for registered users ............................................................................ 10 1.6. Conventions......................................................................................................... 11 CHAPTER 2. APPLICATION STRUCTURE AND TYPICAL DEPLOYMENT SCENARIOS .............................................................................................................. 12 2.1. Application architecture ....................................................................................... 12 2.2. The algorithm of application functioning ............................................................. 13 2.3. Typical deployment scenarios............................................................................. 15 2.3.1. Installing the application along corporate network perimeter...................... 16 2.3.2. Installing the application inside your mail system........................................ 18 CHAPTER 3. INSTALLING THE APPLICATION......................................................... 20 3.1. Installing the application on a server running Linux ........................................... 20 3.2. Installing the application on a server running FreeBSD..................................... 21 3.3. Installation procedure .......................................................................................... 22 Step 1. Preparing the system ......................................................... 22 Step 2. Copying application files to destination directories on your server .................................................................... 22 Step 3. Post-installation tasks ........................................................ 22 3.4. Configuring the application.................................................................................. 23 3.5. Installing the Webmin module to manage Kaspersky SMTP-Gateway ............ 25 CHAPTER 4. USING THE APPLICATION................................................................... 27 4.1. Updating the anti-virus databases ...................................................................... 27 4.1.1. Automatic updating of the anti-virus databases........................................... 29 4.1.2. Manual updating of the anti-virus databases............................................... 29 4.1.3. Creating a shared directory for storing and sharing database updates...... 30 4.2. Anti-virus protection of email traffic ..................................................................... 31 4 Kaspersky® SMTP-Gateway 5.5 for Linux/Unix 4.2.1. Creating groups of recipients/senders ......................................................... 31 4.2.2. General message processing algorithm ...................................................... 34 4.2.3. Main tasks..................................................................................................... 36 4.2.3.1. Deliver messages without changes ...................................................... 36 4.2.3.2. Delivery of clean or disinfected messages only.................................... 37 4.2.3.3. Removing infected attachments............................................................ 38 4.2.3.4. Replacement of infected attachments with standard notifications ....... 39 4.2.4. Additional tasks............................................................................................. 40 4.2.4.1. Block delivery of messages to recipients .............................................. 40 4.2.4.2. Deliver infected messages .................................................................... 41 4.2.4.3. Delivery of notifications to the sender, administrator and recipients .... 42 4.2.4.4. Additional filtering of objects by name and type.................................... 43 4.2.4.5. Backing up (quarantine, backup storage) ............................................. 44 4.2.4.6. Automatically add incoming and outgoing mail to archives.................. 45 4.3. Protection from hacker attacks and spam .......................................................... 46 4.4. Managing license keys........................................................................................ 47 4.4.1. Viewing information about license keys....................................................... 48 4.4.2. Renewing your license ................................................................................. 49 4.4.3. Removing a license key ............................................................................... 50 CHAPTER 5. ADVANCED APPLICATION SETTINGS .............................................. 51 5.1. Configuring anti-virus protection of mail traffic.................................................... 51 5.1.1. Scanning and disinfecting messages .......................................................... 51 5.1.2. Using the iCheckerTM technology................................................................. 51 5.2. Setting up application timeouts ........................................................................... 52 5.3. Setting performance restrictions ......................................................................... 53 5.4. Setting up connection receiving interfaces ......................................................... 55 5.5. Setting up the routing table ................................................................................. 55 5.6. Checking the configuration file syntax ................................................................ 56 5.7. Syntax check in notification templates................................................................ 57 5.8. Work with backup storage and the quarantine directory.................................... 57 5.9. Management of application working queue........................................................ 59 5.10. Managing the application .................................................................................. 62 5.11. Control of application activity............................................................................. 63 5.12. Customizing date and time formats .................................................................. 64 5.13. Reporting options .............................................................................................. 64 5.14. Additional informational header fields in messages......................................... 66 Contents 5 CHAPTER 6. TESTING APPLICATION OPERABILITY ............................................. 67 6.1. Testing the application using Telnet ................................................................... 67 6.2. Testing the application using EICAR .................................................................. 69 CHAPTER 7. UNINSTALLING THE APPLICATION ................................................... 71 CHAPTER 8. FREQUENTLY ASKED QUESTIONS................................................... 72 APPENDIX A. SUPPLEMENTARY INFORMATION ABOUT THE PRODUCT 78 A.1. Distribution of the application files in directories ............................................... 78 A.2. Kaspersky SMTP-Gateway configuration file ................................................... 82 A.3. Use of external configuration files ..................................................................... 98 A.4. Control signals for the smtpgw component..................................................... 100 A.5. Control files....................................................................................................... 100 A.6. Application statistics......................................................................................... 101 A.7. Command line options for the smtpgw component........................................ 106 A.8. Smtpgw return codes....................................................................................... 108 A.9. Command line options for licensemanager .................................................... 109 A.10.Licensemanager return codes......................................................................... 109 A.11.Keepup2date command line options .............................................................. 110 A.12.Keepup2date return codes .............................................................................. 110 A.13.Format of messages about template syntax check-up................................... 111 A.14.Return codes for the kltlv utility........................................................................ 113 A.15.Command line options of the klmailq utility..................................................... 113 A.16.Command line options for the klmaila utility.................................................... 114 A.17.Return codes for the klmaila and klmailq utilities ............................................ 115 A.18.Format of messages about anti-virus scanning.............................................. 115 A.19.Notifications about actions applied to the message ....................................... 116 APPENDIX B. KASPERSKY LAB...................................................................... 119 B.1. Other Kaspersky Lab Products ....................................................................... 120 B.2. Contact Us........................................................................................................ 124 APPENDIX C. LICENSE AGREEMENT............................................................ 125 CHAPTER 1. KASPERSKY® SMTP-GATEWAY 5.5 FOR LINUX/UNIX Kaspersky® SMTP-Gateway for Linux/Unix (hereinafter referred to as Kaspersky SMTP-Gateway or the application) is designed for anti-virus processing of SMTP mail traffic. The application is a full-featured mail relay (compliant with IETF RFC internet standards) that runs under Linux, FreeBSD and OpenBSD operating systems. The application allows the user to: · · · · · Scan email messages for viruses. Detect infected, suspicious, corrupted, attachments and message bodies. and password-protected Perform anti-virus processing (including disinfection) of infected objects revealed in email messages by scanning. Provide additional email traffic filtering by names, MIME types of attachments, and apply certain processing rules to the filtered objects. Maintain archives of all email messages sent and/or received by the application, if this is required by the internal security policy of the company. Use the technology of DNS black lists (RBL) to filter spam. Compose "white" and "black" lists of senders/recipients for use by the application while processing e-mail traffic. Enable restrictions for SMTP connections providing protection against hacking attacks and preventing application use as an open mail relay for unsolicited email messages. Limit the load on your server by configuring the application settings and SMTP parameters. Notify senders, recipients, and the administrator about messages containing infected, suspicious, or corrupted objects. Quarantine messages identified as spam or probable spam as well as messages containing infected, suspicious, corrupted or passwordprotected objects. · · · · · · Kaspersky® SMTP-Gateway 5.5 for Linux/Unix 7 · Update the anti-virus databases. The application retrieves updates from the update servers of Kaspersky Lab. The application detects and cures infected objects using the anti-virus databases. During scans, the contents of each file are compared to the sample code of known viruses contained in the database. Please keep in mind that new viruses appear every day and therefore we recommend maintaining the anti-virus databases in an up-to-date state. New updates are made available on Kaspersky Lab update servers every hour. · Configure and manage Kaspersky SMTP-Gateway either from a remote location using Webmin web-based interface, or locally, using standard OS tools such as command line options, signals, by creating special command files or by modifying the configuration file of the application. Monitor the anti-virus protection and view the statistics and application logs. · 1.1. What's new in version 5.5 Version 5.5 of Kaspersky SMTP-Gateway has been enhanced with the following additional ...