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Tumbleweed

Email Firewall

Administrator’s Guide

Release 6.2

Tumbleweed® Communications Corp. 700 Saginaw Drive

Redwood City, CA 94063 (650) 216-2000

(2)

Copyright Notice

The contents of this manual, the associated Tumbleweed Active Agents™, Tumbleweed SecureTransport™, Integrated Messaging Exchange™ (IME™) software, Messaging Management System™ (MMS™), Tumbleweed Dynamic Anti-spam Service™, Tumbleweed Email Firewall™ (EMF™), Tumbleweed Validation Authority™, Tumbleweed Valicert Validation Authority™ and other computer programs (hereinafter collectively called “Tumbleweed Software”) offered by Tumbleweed Communications Corp. (Tumbleweed) are the property of Tumbleweed and are copyrighted. Use of Tumbleweed Software is governed by the license agreement

accompanying the original media. Your right to copy Tumbleweed Software and its documentation is limited by copyright law. Making copies, adaptations, or compilation works (except copies of Tumbleweed Software for archival purposes or as an essential step in the utilization of the program in conjunction with the equipment) without prior written authorization from Tumbleweed is prohibited by law.

Tumbleweed may revise this publication from time to time without notice. Copyright 1997-2004 Tumbleweed Communications Corp.

All rights reserved.

Some of the processes, arrangements, user interfaces, transaction sequences, site and system architectures, data arrangements, and data processing algorithms, described or embodied in the Tumbleweed Software, are covered by one or more of the following U.S. Patents Nos. 5,790,790; 6,061,448; 6,119,137; 6,151,675; 6,192,407; 399,836; 6,385,655; 6,470,086; 6,487,599; 6,502,191; 6,516,411; 6,529,956; 6,609,196; 6,651,166; 6,725,381 and 6,748,529.

Restricted Rights Legend

Use, duplication or disclosure by the Government is subject to restrictions set forth in subparagraphs (a) through (d), excluding subparagraph (c)(2)(iv), of FAR 52.227-19 when applicable, or in DFARS 227.7202-3, and in similar clauses in the NASA FAR Supplement.

Trademarks

Tumbleweed®, is a registered trademark, and Integrated Messaging Exchange™, IME™, Messaging Management System (MMS)™, Secure Inbox™, Secure Envelope™, Secure Redirect™, Secure Response™, IME Statements™, IME Developer™, IME Messenger™, Tumbleweed Secure Mail™, Tumbleweed Dynamic Anti-spam Service™, Tumbleweed Email Firewall™ (EMF™), Tumbleweed Message Protection Lab™, Tumbleweed Active Agents™, Tumbleweed SecureTransport™, Tumbleweed Validation Authority™ and Tumbleweed Valicert Validation Authority™ are trademarks of Tumbleweed Communications Corp.

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Contents

Preface xxv

Chapter 1

Introduction

1

1.1 Intended Audience ... 2

1.2 Overview of Email Firewall 6.2 ... 3

1.3 Other Documentation ... 4

Chapter 2

Setting Up Email Firewall Administration

7

2.1 Overview of Administrator Setup Tasks ... 8

2.2 Administrative Security ... 9

2.2.1 Web Administration Access Controls ... 9

2.2.2 Logging In ... 10

Setting Up Secure Login ... 10

2.2.3 Main Menu ... 12

2.3 System Status ... 14

2.3.1 Info and Alerts Status ... 14

2.3.2 Message Queues Status ... 17

2.3.3 Email Firewall Services Status ... 19

Automatic Email Firewall Services Restarts ... 21

2.4 Setting Up Admin Roles and Accounts ... 21

2.4.1 Admin Roles Access and Capabilities ... 23

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Queues ...25

Policies ...25

Policy Modules ...25

Directory ...26

Logs and Reports ...26

Setup and Configuration ...26

2.4.2 Assigning and Creating Admin Roles ...27

2.4.3 Creating New Administrator Accounts ...29

2.4.4 Preferences ...31

2.5 Setting Up Relays ...32

2.5.1 Relay Settings Configuration ...33

2.5.2 Global Relay Settings ...34

Stopping Inbound or Outbound Mail ...34

Enabling and Disabling Preprocessing and Policy Engine ...35

2.5.3 Limit Settings ...36

Maximum Connections and Delay Settings ...36

Network Connections and Replication Environments ...37

Message Size and Recipient Limits ...37

2.5.4 Identity Settings ...38

Setting the SMTP Port ...38

Specifying the Relay Host Name ...39

Specifying the SMTP Greeting and Postmaster Information ...39

Hiding Email Firewall Version Number in Message Headers ....40

Local MX Hosts Configuration ...41

2.5.5 Specifying the DNS Servers ...41

2.5.6 Specifying DNSBL Settings ...42

2.5.7 Exceptions to Mail Delivery ...43

Specifying Illegal Characters in Email Address Formats ...43

Dropping Mailbox-Only Recipients ...44

Deleting Bounced Notifications ...44

2.5.8 Miscellaneous Relay Settings ...45

Delivery Status Notifications ...46

Alternate Lookups ...46

Load Balancing by Randomizing Order of MX Hosts ...47

Received Headers Content ...47

SMTP Relay Delay and Non-Delivery Notifications Sent ...48

2.5.9 Network Connections Concepts ...49

Understanding Internal vs. External Networks ...50

Rejecting Connections From Malicious Clients ...50

2.5.10 Domain-Based Authentication Protocols ...51

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Servers, Routing Rules and TLS ... 58

Configuring Email Firewall To Prevent Open Relaying ... 59

2.5.13 Setting Up Mail Routing Rules ... 60

Setting Up Exact Matching for a Domain ... 65

Best Match Algorithm and Wildcards ... 66

Editing Routing Rules ... 66

2.5.14 Address Rewriting Concepts ... 67

Address Rewriting Rules ... 68

Match Specifiers ... 68

Rewrite Actions ... 69

Matching and Substitution Examples ... 70

A Complete Example ... 70

2.5.15 Setting Up Address Rewriting ... 71

Creating Custom Address Rewriting Rules ... 74

2.5.16 Testing Address Rewriting ... 75

2.5.17 SMTP Relay and Message Retry Configuration ... 76

2.5.18 Troubleshooting the SMTP Relay Service ... 76

SMTP Relay Service Not Accepting Messages ... 76

Email Firewall Relay Not Identifying Itself Properly ... 77

Troubleshooting Outbound Message Backlogs ... 78

Troubleshooting TLS ... 80

2.6 Setting Up Anti-virus and Anti-spam ... 80

2.6.1 Setting Up Anti-virus and Anti-spam Downloads ... 82

Virus Scanning Heuristics ... 84

2.6.2 Setting Up Dynamic Anti-spam Service Settings ... 84

Adding Spam Categories to Scanned Messages ... 85

Do Not Scan Messages Received From Internal Networks ... 86

Do Not Scan Messages Larger Than 200 KB In Size ... 86

2.7 Setting Up Global Policy Settings ... 87

2.7.1 Setting Up Peak Time for Policy Actions ... 87

2.7.2 Setting Up Archive for Policy Actions ... 88

Archiving Options for Virus-Infected Messages ... 90

2.7.3 Setting Up Other Global Policy Options ... 91

Scanning Bytes of Non-Text Attachments ... 93

Limitations in Scanning Non-Text Attachments ... 93

Marking Text Parts That Use Unsupported Character Sets ... 94

Marking Messages With Invalid MIME Structure or Illegal Character Encoding as Decomposition Failures ... 94

Isolating BCC recipients on Separate Copies of the Message .... 95

Quarantining Messages That Grow to Excessive Size ... 96

Quarantining Deeply Nested MIME Messages ... 96

2.7.4 Setting Up Policy-based Routing ... 97

Avoiding Infinite Message Looping ... 99

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2.8.2 Setting Up Centralized Event Logging and Reporting ...101

Prerequisites to Enabling Centralized Event Logging and Reporting for Email Firewall Systems in a Domain ...101

Prerequisites to Enabling Centralized Event Logging and Reporting for Email Firewall Systems in Workgroups ...102

Enabling and Setting Up Centralized Event Logging and Reporting ...103

2.9 Other Setup Tasks ...105

2.9.1 Setting Up Message Queues ...105

What is the Personal Quarantine Manager? ...106

2.9.2 Setting Up Reporting ...106

2.9.3 Setting Up Policies ...106

2.9.4 Setting Up the Directory ...107

2.9.5 Setting Up Security ...107

2.9.6 What is the Dynamic Anti-spam Service? ...107

2.9.7 What is Secure Redirect? ...108

2.9.8 What is Secure Messenger? ...108

2.9.9 Setting Up Proxy Servers ...109

Setting up HTTP Proxy Server ...111

Setting up FTP Proxy Server ...111

Chapter 3

Working With Queues

113

3.1 Message Queues Status ...114

3.2 Setting Up Message Queues ...116

3.2.1 Queue Configuration ...119

3.2.2 Setting Up Queue Actions ...120

Resetting Queue Actions ...121

3.2.3 Setting Up Queue Aging ...122

3.2.4 Setting Retry Queue Retry Intervals ...123

3.2.5 Creating Quarantine Custom Queues ...125

3.3 Setting Up Queue Searches ...126

3.3.1 Limitation on Queue Search Results ...126

3.3.2 Creating a Queue Search ...127

3.3.3 Modifying Queue Searches ...130

3.3.4 SQL Jobs and Deleting Messages in Queue Filters ...130

3.4 Working With Messages in the Queues ...131

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3.5.2 Additional Queue Management Tips ... 134

Use Bulk Actions on Messages ... 134

Use Quarantine Queue Threshold Actions ... 135

Use Quarantine Queue Aging ... 135

Create Quarantine Queue Custom Queues ... 135

3.5.3 Checking the Quarantine Queue for Inbound Messages ... 135

3.5.4 Stopping Inbound Message Acceptance ... 136

3.5.5 Getting Rid of Undeliverable Bounced Messages ... 137

3.6 Troubleshooting Inbound and Outbound Queues ... 138

Stopping the SMTP Relay From Accepting More Messages ... 138

3.6.1 Troubleshooting Inbound Queue Backups -- Full File Groups ... 139

3.6.2 Troubleshooting Outbound Queue Backups ... 141

3.7 Using Personal Quarantine Manager ... 142

3.7.1 Personal Quarantine Manager Server ... 143

3.7.2 Quarantine Summary Notification Messages ... 144

QSNs and Quarantine Queue Aging ... 144

User Requests for Access to Quarantined Messages ... 145

Identifying QSN Message Headers ... 145

PQM Server Responses ... 146

3.7.3 Setting Up PQM Server Settings ... 147

Testing the PQM Server ... 148

3.7.4 Specifying User Domains To Receive QSNs ... 149

Editing and Removing User Domains ... 150

3.7.5 Setting Up the QSN Format and Schedule ... 151

Enabling QSN On-demand Access and White-listing ... 154

Turning Off QSN Deliveries ... 155

QSN Format Issues with Outlook Express 6 on Windows 2003 ... 156

3.7.6 Setting Up QSN Access Restrictions ... 156

Tags and Outbound Security Policies ... 157

Procedures for Setting Up QSN Tags ... 158

Editing and Deleting QSN Access Tags ... 160

3.8 PQM Reports Sent to Users ... 161

3.8.1 HTML Format QSN Blocked Messages Reports ... 161

3.8.2 Text Format QSN Blocked Messages Reports ... 165

3.8.3 User Requests for QSNs “On-Demand” ... 166

3.8.4 User Requests for “White List” ... 168

3.8.5 Bookmarking the QSN Update URL ... 168

3.8.6 PQM and Message Security Concerns ... 169

Sending QSNs in the Clear ... 169

Message Contents Not Displayed ... 170

3.9 Using Policies with PQM ... 171

3.9.1 Policies to Prevent QSNs from Being Sent to Specific Users ... 173

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3.10.1 Changing the PQM Server Account Password ...175

3.10.2 PQM Tables that Must Not be Replicated ...175

3.10.3 PQM and IIS Server Configuration Issues ...176

Authentication Methods ...176

PQM Server Anonymous Account ...177

Application Protection ...177

Secure HTTP Access ...178

PQM Server Logging ...179

Diagnosing Authentication Problems ...179

3.11 Troubleshooting the PQM ...181

3.11.1 PQM Notification Service “Not Running” or Not Shown ...181

3.11.2 Localization Issues and PQM Message Display ...182

3.11.3 Duplicate Notifications from Notification Service ...182

3.11.4 Personal Quarantine Manager FAQs ...183

Chapter 4

Working With the Event Log

185

4.1 Setting Up Email Firewall Event Logging ...186

4.1.1 Setting up Global Event Log Settings ...187

4.1.2 Setting Up Logging Levels ...187

4.1.3 Setting Up Event Aging ...188

4.1.4 Event Log Export ...189

4.1.5 Cleanup Jobs and Message Processing ...189

4.1.6 SQL Server Job Events Not Reported ...190

4.2 Searching the Event Log ...190

4.3 Using Event Log Filters ...192

4.3.1 Creating Event Log Filters ...192

4.3.2 Creating Custom Events ...194

4.4 Searching for Message Events ...199

Chapter 5

Understanding Policies

203

5.1 Policy Overview ...204

5.1.1 Definitions ...204

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5.1.2 Example ... 205 Name ... 206 Catch Conditions ... 206 Exclude Conditions ... 207 Actions ... 208 Backup Actions ... 209 Summary ... 209

5.2 Policy Categories and Types ... 210

5.2.1 Basic Mail Filtering Policy Types ... 211

Random Selection ... 213

5.2.2 Attachments Policy Types ... 215

File Attachment Stripping ... 215

Convert UUencoded Attachments to MIME Format. ... 216

5.2.3 LDAP Policy Types ... 216

5.2.4 Virus Policy Types ... 217

Infected Message ... 217

Clean Stamp Uninfected Messages ... 217

5.2.5 Security Policy Types ... 217

5.2.6 SPN Policy Types ... 218

5.2.7 Headers Type Policies ... 218

Remove MIME Headers ... 219

Remove Hostnames and Subdomains From MIME Headers ... 219

Normalize Email Addresses in MIME Headers ... 219

Message Header Fields ... 219

5.3 Email Firewall Directory ... 220

5.3.1 Directory Objects ... 220

Folders ... 221

Domain Records ... 221

Default Domain Record ... 221

User Records ... 222

5.3.2 Default Directory Structure ... 222

All Folder ... 223

External Folder ... 223

Internal Folder ... 224

5.3.3 Viewing Policies Applied to Directory Objects ... 224

5.3.4 Adding New Directory Objects ... 224

Adding Folders ... 225

Adding Domain Records ... 227

Adding User Records ... 228

5.3.5 How Policies and User Records Work Together ... 231

5.3.6 Using LDAP Import ... 232

5.4 How Email Firewall Applies Policies ... 233

5.4.1 Hierarchy of Message Actions ... 233

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5.4.2 How Severity of Action Affects Policy Enforcement ...235

5.4.3 Understanding Policy Inheritance and Overrides ...237

5.4.4 Policy Inheritance Example ...237

5.4.5 Policy Override Example ...238

5.4.6 Preventing Policy Overrides ...238

5.5 General Policy Planning Considerations ...240

5.5.1 Inheritance Is From Parent Folders Only ...240

5.5.2 When to Use Sender Polices ...240

5.5.3 When to Use Recipient Policies ...241

5.5.4 Where To Apply Anti-spam Policies ...241

Using a Recipient Policy for Spam Example ...243

5.5.5 Use Directory Folder Policies Whenever Possible ...243

5.6 Default Policies and Folders ...245

5.6.1 General Rules About Policy Application ...245

5.6.2 Policies Applied to the All Folder ...246

Decompression Errors ...246

Decomposition Errors ...246

Partial Message Block ...247

Virus Hoax Block ...247

5.6.3 Additional Policies Applied to the External Folder ...248

Outbound Size Deferral ...248

5.6.4 Additional Policies Applied to the Internal Folder ...248

EXE Blocking ...250

Inbound Size Deferral ...250

Infected Message (Recipient) ...250

Infected Message (Sender) ...250

Long Filename Quarantine ...251

Multimedia Attachments Deferral ...251

Outbound Message Archival ...251

Résumé Block ...251

Sensitive Info Review ...252

5.6.5 HIPAA Compliance Policy ...252

5.6.6 Dynamic Anti-spam Service Policies ...252

Spam - DAS: Adult ...252

Spam - DAS: High Confidence ...253

Spam - DAS: Moderate Confidence ...253

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Chapter 6

Creating and Editing Policies

255

6.1 Introduction to Policy Building ... 256

6.1.1 Using Multiple Policy Actions ... 256

6.2 Lists and Tags ... 257

6.2.1 Cautions on Using Text Wildcards in Lists ... 258

6.2.2 Word Lists ... 258

Using Wildcards in Word Lists ... 259

Word Lists and Wildcards Caution ... 260

Word List Construction and Weighted Word List Syntax ... 260

Validating and Saving Word Lists Using Advanced Add ... 261

6.2.3 Advanced Add, Character Sets and Lists ... 262

6.2.4 Using Regular Expressions in Word Lists ... 262

6.2.5 Creating a Word List Example ... 263

Plan the New Word List First ... 263

Associate the External Word List and Create the List ... 264

6.2.6 Address Lists ... 265

Address Lists and Wildcards Caution ... 266

6.2.7 Creating an Address List Example ... 266

6.2.8 Attachment Lists ... 268

Viewing File Types for Attachment Lists ... 269

Using Advanced Add and Wildcards in Attachment Lists ... 270

Attachment Lists and Wildcards Caution ... 270

Special Considerations for File Names and File Types ... 271

6.2.9 Creating an Attachment List Example ... 271

6.2.10 Exporting Lists ... 273

6.2.11 Tags ... 274

6.2.12 Creating a New Tag Example ... 275

Advanced Add for Tags ... 277

6.3 Annotations ... 278

6.3.1 Global Settings for In-line Annotations ... 279

Using Placeholders in Global In-line Annotations ... 280

6.3.2 Using Placeholders in Policy Annotation Text ... 281

6.3.3 Skipping Annotation Text ... 281

6.3.4 Annotating All Outbound Mail with a Disclaimer ... 282

Plan the Outbound Disclaimer Policy ... 283

Create the Outbound Disclaimer Annotation ... 284

Create the Outbound Disclaimer Policy ... 285

Apply the New Disclaimer Policy to the Policy Hierarchy ... 285

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6.4 Notifications ...287

6.4.1 Global Notification Settings ...288

Notification Routing ...289

Default Global Notification Settings ...289

6.4.2 Creating a New Notification for a Policy Action ...290

Avoiding Duplicate Notifications ...292

Dropped or Returned Message Notification Option ...293

Virus in Message Notification Option ...293

6.5 Using Events as Policy Actions ...295

6.6 Creating Policies ...296

6.6.1 Viewing the Default Policies ...296

Editing Default Policies to Scan HTML Tags ...296

6.6.2 Creating a New Policy Example ...298

6.7 Applying the Policy to a Directory Object ...301

6.7.1 Adding Policies to Directory Objects ...302

6.8 Using Virus- and File-Stripping Policies ...303

6.8.1 How Virus-Stripping Policies Work ...303

6.8.2 How File-Stripping Policies Work ...304

6.9 Policy Protection Against New Viruses ...305

6.9.1 Defining Content-Based Policies for Viruses ...305

Creating the New Policy ...305

Applying the New Policy to the Directory ...308

Testing the New Policy ...309

6.9.2 Using Policies to Detect HTML Mobile Code ...310

Catching Script Tags ...310

6.9.3 Troubleshooting Virus Protection ...311

Common Ways Email Firewall is Misconfigured ...311

Other Channels for Virus Infiltration ...312

6.10 Using Headers Type Policies ...313

6.11 Using DAS Message Properties ...315

6.11.1 Default Dynamic Anti-spam Service Policies ...315

6.11.2 What a DAS Policy Should Look For ...316

DAS Message Properties Added ...317

DAS Message X-headers Added ...317

Acting on Spam Messages ...318

6.11.3 Using the Broadcast Content Rating in Policies ...319

6.11.4 Applying the Anti-spam Policy to the Directory ...319

6.11.5 Testing the Anti-spam Policy ...320

Special Test Keywords for Testing an Anti-spam Policy ...321

6.11.6 Creating a Broadcast Exception Policy ...321

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Conditions Not Configured Properly ... 324

Directory Object Has Not Inherited a Policy ... 324

Exclude Conditions Not Configured Properly ... 325

Two Similar Policies Specify Different Actions ... 325

Policy Should Be Recipient (or Sender) ... 325

Address List Uses Non-Word Characters ... 325

Annotations Not Skipped ... 325

Signed Messages Not Being Caught ... 326

6.12.2 Other Problems ... 326

Virus Pattern File Needs to Be Updated ... 326

Virus Scan Engine Needs to Be Updated ... 326

SMTP Relay Service Is Stopped ... 326

Policy Enforcement Not Enabled ... 326

List Not Configured Correctly ... 327

Notification Address Is Incorrect ... 327

Queue Backups ... 327

Chapter 7

Dynamic Anti-Spam Service

329

7.1 Introduction to Stopping Spam ... 330

7.1.1 At-the-Relay Protection ... 331

7.1.2 Incoming Message Classification ... 331

7.1.3 Acting on Spam Messages ... 332

7.2 Dynamic Anti-spam Service Overview ... 332

7.2.1 Email Firewall Spam Analysis Engine ... 332

7.2.2 Email Firewall Download Service ... 333

7.2.3 Tumbleweed Message Protection Lab ... 333

7.3 Dynamic Anti-Spam Service Architecture ... 334

7.3.1 Mail Flow with the Dynamic Anti-spam Service ... 334

7.4 How the Engine Processes Messages ... 337

7.4.1 What the Engine Looks For ... 337

7.4.2 Messages Not Analyzed by the Service ... 338

Large Messages ... 338

Secure Response Service Messages ... 338

SPN or Encrypted Messages ... 339

7.4.3 Internal Message Analysis ... 339

7.5 Message Categorization ... 340

7.5.1 Message Assessment and Properties Added ... 340

What the Spam Confidence Rating Means ... 341

What the Spam Content Rating Means ... 341

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7.6 Dynamic Anti-spam Service Administration ...343

7.6.1 Spam Analysis Engine Maintenance ...344

7.6.2 SMTP Relay Routing Option Behavior ...344

7.6.3 Enabling and Disabling the Service ...344

Moving All Messages Out of the Spam Analysis Queue ...345

7.6.4 Enabling DAS X-headers ...345

Spam Filter Version Identifier ...345

7.6.5 Removing Internal Mail From Engine Processing ...346

7.6.6 Adding Large Messages to Engine Processing ...346

7.6.7 License Changes And License Events ...347

7.6.8 Error Handling in the Spam Analysis Engine ...347

7.6.9 Performance Counters ...348

Preliminary Steps Required for Log Mode ...349

Setting Up a Spam Analysis Engine Counter ...349

Starting a Spam Analysis Engine Counter ...350

Stopping a Spam Analysis Engine Counter ...350

7.6.10 Spam Analysis Engine Event Log Events ...351

7.7 Dynamic Anti-spam Filter Downloads ...351

7.7.1 Downloading Filter Data From the FTP Server ...351

7.7.2 Updating the Email Firewall Database Tables ...352

7.8 Download Service Maintenance ...353

7.8.1 Manually Checking for Updates ...353

7.8.2 Rolling Back To An Earlier Filter Data Version ...353

7.8.3 Removing A Corrupted Filter Version ...353

7.8.4 Increasing MMSConfigData Filegroup Size ...354

7.8.5 Troubleshooting Updates ...354

7.9 The Tumbleweed Message Protection Lab ...355

7.9.1 Message Protection Lab Tools ...356

7.9.2 Submitting Examples To the Lab ...356

How To Forward Unmarked Spam ...357

Microsoft Outlook and Netscape Users ...357

Automating Spam Submittal For Your Users ...357

Submitting False Positives ...359

Submitting False Positives Using Email Firewall Web Admin 359 7.10 The Anti-spam Toolbox ...360

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Chapter 8

Email Encryption and Authentication Overview

363

8.1 Introduction to Email Encryption and Authentication in EMF ... 364

8.2 S/MIME and OpenPGP Overview ... 365

8.2.1 Email Firewall and S/MIME ... 366

8.2.2 Email Firewall and OpenPGP ... 368

8.3 Email Firewall Gateway-to-Gateway Security ... 369

8.3.1 Understanding Local Secure Domains ... 370

8.3.2 Setting up SPN Links ... 371

8.3.3 Certificate Import and Export ... 372

8.3.4 The Email Firewall SPN-Type Policies ... 372

Non-SPN Message Received From SPN Domain (Inbound) ... 372

Imperfect SPN Message Received (Inbound) ... 372

Unable to Encrypt and Sign to SPN Domain (Outbound) ... 372

8.4 Email Firewall Security using TLS ... 373

TLS Certificate Requirements ... 374

8.5 Email Firewall Server-to-Client Proxy Security ... 375

8.5.1 How Email Firewall Performs Proxy Security ... 377

Proxy Encryption ... 379

Proxy Decryption ... 380

Proxy Signature ... 380

Proxy Verification ... 380

Automatic Lookup of User Certificates ... 381

8.5.2 Email Firewall and Automatic Certificate Association. ... 382

Policy Usage ... 382

New Certificates ... 383

Policy Limitations ... 383

Root Key Purpose ... 383

8.5.3 The Email Firewall Proxy Security Policy Types ... 384

Proxy Decrypt and Verify ... 384

Proxy Encrypt and/or Sign ... 384

Automatic Certificate Association (for S/MIME only) ... 384

Unencrypted Message Filter ... 385

Client Encryption and Signature ... 385

8.6 Email Firewall Client-to-Client Security ... 385

8.6.1 “Allow” Client-to-Client Security Policies ... 387

Plaintext Access ... 387

Understanding Plaintext Access ... 388

Allow Security Stripping ... 388

8.6.2 “Require” Client-to-Client Security Policies ... 389

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8.7 The Sender Signature Policy Type ...391

8.7.1 Background ...391

8.7.2 Conceptual Overview ...392

8.7.3 Email Firewall Signing Certificate Validation ...393

8.8 Understanding Certificate Harvesting ...394

8.8.1 S/MIME Certificate Harvesting ...394

8.8.2 OpenPGP Key Harvesting ...394

8.9 Understanding Certificate and PGP Key Responders ...395

8.9.1 Certificate Responder and Server Certificates ...395

8.9.2 Certificate Responder and Proxy Certificates ...396

8.9.3 Understanding PGP Key Responder ...396

8.10 Third-Party Certificates and Email Firewall ...397

8.10.1 Supported Third-Party Server S/MIME Certificates ...398

8.10.2 Third Party TLS Certificate Requirements ...399

8.10.3 SMG Mode Certificates ...400

8.11 Third Party PGP Keys and Email Firewall ...400

8.12 Understanding Certificate Rollovers ...401

8.12.1 Server Certificate Expiration and Proxy Security ...402

8.12.2 Certificate Rollover Coordination Required ...403

8.12.3 Certificate Rollover Preparation Checklist ...404

8.12.4 Certificate Rollover Process Concepts ...404

Generate or Import the New Certificate ...404

Distribute The New Certificate ...405

Associate the New Certificate with the Local Secure Domain .405 Complete the Rollover ...406

Certificate Rollover Completion Wrap-Up and Consequences 407 8.12.5 Proxy PGP Key Rollover ...407

8.13 The PGP Trust Model ...408

8.14 Trust and Interoperability of S/MIME Certificates ...408

8.14.1 Understanding Key Size Issues ...409

8.14.2 Understanding Root Key Purposes ...411

8.14.3 Understanding S/MIME Interoperability Issues ...412

Trusting a Certificate ...412

Trusting Self-Signed Certificates ...412

Associating an Email Address with a Certificate ...413

Associating Self-Signed Certificates ...413

Understanding Server or Role Certificates in Email Firewall ..413

Understanding Proxy Certificates in Email Firewall ...414

8.14.4 Email Firewall S/MIME Certificate Verification ...416

8.14.5 Establishing Trust Relationships ...416

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8.14.8 Email Firewall and CRL Distribution Points ... 420

8.14.9 Email Firewall and CRL Processing Precedence ... 421

8.15 Frequently Asked Questions ... 422

8.16 Commonly Used Security Terms ... 424

Certificate ... 424

Certificate Authority ... 424

Certification Practice Statement ... 424

Certificate Revocation List (CRL) ... 424

CRL Distribution Point ... 424

Chain Trust, or Trust According to Certificate Status ... 425

Decryption ... 425 Digital Signature ... 425 Encryption ... 425 Fingerprint ... 425 Key ... 425 OpenPGP ... 425 Private Key ... 426 Public Key ... 426 S/MIME ... 426 SMG ... 426 SPN ... 426 TLS ... 427

Chapter 9

Security Configuration

429

9.1 Setting Up Email Firewall Security ... 430

9.1.1 Email Firewall Security Prerequisites ... 431

9.1.2 Using the Email Firewall Security Setup ... 432

9.2 Setting Up Key Pairs and Certificates for S/MIME ... 433

9.2.1 Generating an Email Firewall Certificate and Key Pair ... 434

9.2.2 Sharing the Certificate and Root Key ... 435

Exporting the Certificate and Root Key ... 436

Publishing the Certificate as a Root Key ... 436

9.2.3 Enabling Email Firewall Certificate Responder ... 437

What an External User Must Do to Invoke Certificate Responder ... 437

9.2.4 Importing Third-Party Server Certificates ... 438

Entrust-Specific Requirements for Certificates ... 438

From Entrust Certificate and Private Key to PKCS#12 File .... 439

VeriSign-Specific Requirements for Certificates ... 439

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9.2.6 Obtaining Certificate Authority Root Certificates ...440

Obtaining Entrust Root Certificates ...441

Obtaining Verisign Root Certificates ...441

9.3 Setting Up PGP Keys ...442

9.3.1 Generating a PGP Proxy Domain Key ...443

9.3.2 Enabling Email Firewall PGP Key Responder ...444

What an External User Must Do to Invoke PGP Key Responder ...444

9.3.3 Importing PGP Keys Into Email Firewall ...445

9.4 Setting Up Certificates for TLS ...445

9.4.1 Creating a TLS Message Exchange Policy ...448

9.5 Setting Up for Sender Signature Policies ...451

9.5.1 Administrator Actions Required ...451

9.5.2 Expected Signing Behaviors ...454

9.5.3 Troubleshooting Sender Signature Policies ...456

9.6 Setting Up a Secure Public Network ...458

9.6.1 Defining and Associating Local Secure Domains ...458

Editing a Local Secure Domain ...460

9.6.2 Enabling SPN Links ...461

Requesting an SPN Link From External Email Firewall Servers ...461

9.6.3 Setting Up Email Firewall to Respond to SPN Links ...463

Checking For and Accepting SPN Links ...465

9.6.4 Verifying the SPN and Security for the Domain ...466

9.6.5 Creating a Policy to Check for Successful SPN ...467

9.7 Setting Up for SMG Mode ...471

9.7.1 Set Up Differences in SMG Mode ...471

9.8 Setting Up S/MIME Proxy Security ...474

9.8.1 Configuring S/MIME Proxy Security Checklist ...474

9.8.2 Configuring S/MIME Proxy Security Example ...476

9.8.3 Generating a Key Pair and Certificate ...476

9.8.4 Configuring Email Firewall to Use the New Certificate ...477

9.8.5 Exporting and Publishing the Root Certificate ...478

9.8.6 Enabling S/MIME Proxy Certificate Usage and Responder ...479

9.8.7 Creating the S/MIME Proxy Security Policies ...480

Creating a Client Encryption and Signature Policy ...480

Creating a Detect Cert-query Policy for the External Folder ....482

Creating a Proxy Decrypt and Verify Policy ...484

Creating a Proxy Encrypt and/or Sign Policy ...485

9.8.8 Enabling Automatic Certificate Association ...490

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9.9 Rolling Over S/MIME Certificates ... 497

9.9.1 Rolling Over a Certificate ... 497

Generating or Importing The New Certificate ... 497

Distributing The New Certificate ... 498

Associating The Server Certificate With the Local Domain .... 499

Enabling Proxy Partners To Obtain The Proxy Certificates ... 499

Completing the Certificate Rollover ... 500

9.10 Downloading Certificate Revocation Lists ... 500

9.10.1 Specifying CRL Source and Download Schedule ... 501

9.10.2 Specifying the HTTP Proxy Server for Downloads ... 502

9.10.3 Manually Invoking CRL Downloads ... 502

9.11 Specifying the CRL DP LDAP Lookup ... 503

9.12 Setting Up OpenPGP Proxy Security ... 504

9.12.1 Configuring OpenPGP Proxy Security Checklist ... 504

9.12.2 Configuring OpenPGP Proxy Security Example ... 506

9.12.3 Generating an Internal PGP Key (Local Key) ... 506

9.12.4 Configuring Email Firewall to Use the New PGP Key ... 507

9.12.5 Creating the OpenPGP Proxy Security Policies ... 507

Create a Policy to Detect PGP Keys Sent to EMF Server ... 508

Creating an Proxy Decrypt and Verify Policy ... 509

Creating a Proxy Encrypt and/or Sign Policy ... 511

9.12.6 Creating the User Records ... 516

9.12.7 Exchanging and Verifying PGP Keys ... 517

9.12.8 Completing the Association ... 518

9.12.9 Putting It All Together ... 518

9.13 Rolling Over OpenPGP Proxy Domain Keys ... 519

9.13.1 Rolling Over a PGP Key ... 519

Generating the New PGP Key ... 519

Distributing the New PGP Key ... 520

Associating the Server PGP Key With the Local Domain ... 520

Enabling Proxy Partners To Obtain The Proxy PGP Key ... 520

9.14 Setting Up S/MIME and OpenPGP Client-to-Client Security 521 9.14.1 Creating Plaintext Access Policies ... 521

9.14.2 Creating Allow Security Stripping Policies ... 524

9.14.3 Creating an Unencrypted Message Filter Policy ... 525

Sender-Based Unencrypted Message Filter Solution ... 527

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Chapter 10

Administrative Tools

531

10.1 Email Firewall Directory Tools ...532

10.1.1 Find User ...532

10.1.2 LDAP Import ...533

10.2 Setting Up LDAP Directory Imports ...534

10.2.1 Configuring LDAP Import Mappings ...535

Attribute Mapping ...536

10.2.2 Understanding the Directory Import Sequence ...539

Special Considerations When Using Active Directory ...540

10.2.3 Identifying the Data Source for LDAP Import ...540

LDAP Import and MS Exchange Issue ...544

10.2.4 Configuring a Query for LDAP Import ...545

10.2.5 Configuring a Mapping for LDAP Import ...548

10.2.6 The Email Firewall LDAP Import Process ...550

10.3 Performing the LDAP Import ...552

10.3.1 LDAP Import Scheduling ...553

How Deleting Directory Import Sequences Affects User Records ...555

10.3.2 Creating LDIF Files ...555

10.3.3 Stopping Updating of User Records ...557

10.3.4 Cleaning Up the Directory ...558

10.3.5 Email Firewall LDAP Import Log File ...559

10.4 Using the Command Line Program Tools ...560

10.4.1 MMSLDIFImportConfig ...560

10.4.2 EMFSave ...561

10.5 Using the Word List Tester ...564

10.5.1 Validating Word Lists ...564

10.5.2 Checking Word List Processing Time ...566

10.5.3 Checking Address List Processing Time ...567

10.6 Using the PrivateKeyWizard Tool ...568

10.6.1 Specifying a New Password ...569

10.6.2 Inputting a Password to Protect Private Keys ...571

10.6.3 Importing Private Keys from a PKCS#12 File ...574

10.6.4 Importing PGP Keys ...579

10.6.5 Removing Certificates and PGP Keys ...582

10.7 Using the Email Firewall Diagnostics Utility ...582

10.7.1 SQL Server Related Tests ...583

10.7.2 Email Firewall Related Tests ...584

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10.8 Using the EMFDebugLogCapture Tool ... 590

10.9 Using EMFSave ... 592

10.9.1 EMFSave and Administration Data ... 592

10.9.2 EMFSave and Replication ... 593

10.9.3 Starting EMFSave ... 593

10.9.4 Restoring EMFSave Files ... 599

Missing Data and Restore Errors ... 601

10.9.5 Using EMFSave in a Cluster Environment ... 601

10.10 Using the Email Firewall Update Service ... 602

10.11 Using the Configuration Editor ... 609

Chapter 11

Email Firewall Reports

611

11.1 Setting Up Email Firewall Reports ... 612

11.1.1 Global Reports Setup ... 612

11.1.2 Reporting Statistics and Queues Issues ... 615

11.2 Volume Reports ... 616

11.2.1 Attachment Volume and Size ... 617

11.2.2 Message Volume and Size ... 617

11.2.3 Message Volume by Policy Disposition Report ... 618

11.2.4 Attachment Volume for a Specific Attachment Type ... 619

11.2.5 Virus Type and Volume ... 619

11.2.6 SPF Volume Report ... 620

11.2.7 Caller ID Volume Report ... 621

11.2.8 Spam Volume Report ... 621

Interpreting the Spam Volume Report ... 623

11.3 Frequency Reports ... 624

11.3.1 Frequently Detected Virus ... 624

11.3.2 Frequent Policy Violation ... 624

11.3.3 Frequent Receiving Domains ... 624

11.3.4 Frequent Recipient Policy Violation ... 624

11.3.5 Frequent Sender Policy Violation ... 625

11.3.6 Frequent Sending Domains ... 625

11.3.7 Frequent Sending IP Addresses ... 625

11.3.8 Frequent Virus Sender ... 625

11.3.9 Frequent SPF and Caller ID Violators ... 626

11.3.10Frequent Senders Released from Quarantine ... 626

11.4 User Reports ... 627

11.4.1 Attachment Volume for Specific Recipient ... 627

11.4.2 Message Volume for Specific Recipient ... 627

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11.4.5 Message Volume for Specific Sender ...628 11.4.6 Policy Violation for Specific Sender ...628 11.4.7 Virus Detected for Specific Sender ...628 11.5 Audit Reports ...629 11.5.1 Directory and Policy Audit ...629 11.5.2 Directory Audit ...629 11.5.3 Policy Audit ...629 11.5.4 Directory and Policy Audit for a Single User ...629 11.5.5 Directory Audit for a Single User ...630 11.5.6 Policy Audit for a Single User ...630 11.6 Customizing Email Firewall Reports ...630 11.6.1 Customizing Volume Reports ...631 11.6.2 Customizing Frequency Reports ...632 11.6.3 Customizing User Reports ...633 11.6.4 Customizing Audit Reports ...634 11.7 Printing and Saving Reports ...635 11.7.1 Printing Reports ...635 11.7.2 Saving Reports ...636

Appendix A

File Types Scanned

639

A.1 General Overview ...640 A.1.1 File Types and File Type Lists Provided ...640 A.1.2 Scanning Limitations ...642 A.1.3 Compressed Files and Embedded Objects ...643 Embedded Objects in Microsoft Office Files ...643 Limitations in File Type Decompression and Decomposition ..644 A.2 “All Supported” File Types ...645 A.2.1 All Supported Compressed Files ...645 A.2.2 All Supported Database Files ...645 A.2.3 All Supported Document Files ...646 A.2.4 All Supported Drawing Files ...647 A.2.5 All Supported Executable Files ...647 A.2.6 All Supported Image Files ...648 A.2.7 All Supported Multimedia Files ...648 A.2.8 All Supported Password-Protected Archive Files ...649 A.2.9 All Supported Password-Protected Files ...649 A.2.10 All Supported Presentation Files ...649

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A.3.3 AutoCAD ... 651 A.3.4 Corel Draw ... 651 A.3.5 Help Files ... 651 A.3.6 Lotus 123 ... 652 A.3.7 Microsoft Excel ... 652 A.3.8 Microsoft PowerPoint ... 652 A.3.9 Microsoft PowerPoint with Macros ... 652 A.3.10 Microsoft Word ... 652 A.3.11 Paradox ... 653 A.3.12 Quattro/Quattro Pro ... 653 A.3.13 Windows Bitmap (BMP) ... 653 A.3.14 WordPerfect ... 653 A.4 File Types Recognized ... 655 A.5 File Types Scanned ... 659 A.5.1 Word Processing Formats ... 659 Adobe Portable Document Format (PDF) ... 660 A.5.2 Picture Formats ... 660 A.5.3 Presentation Formats ... 661 A.5.4 Spreadsheet Formats ... 661 A.5.5 Multimedia Formats ... 661 A.5.6 Compression Formats ... 662

Appendix B

Code Set Support

663

B.1 Definitions and Concepts ... 664 B.1.1 Characters and Code Sets ... 664 B.1.2 Message Text Parts ... 665 B.1.3 Non-ASCII-7 Text in Message Headers ... 665 B.1.4 The Default Recipient Locale ... 665 B.2 Data In The Email Firewall Database ... 666 B.2.1 Word List Data ... 666 Special Treatment of Japanese Text On Word Lists ... 667 B.2.2 Issues With Handling Non-English Text ... 667 Personal Quarantine Manager and Character Sets ... 668 B.3 Extraction of Text From Message Content ... 669 B.3.1 Extraction of Text From Attachments ... 669 B.3.2 Handling Text From Unsupported or Unidentified Code Sets ... 669 B.3.3 Handling of Unmapped Characters ... 670 B.4 Policy Engine Expected Behaviors ... 671 B.4.1 Annotations ... 671 Inline Annotations ... 671

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B.4.2 Notifications ...672 B.4.3 Events ...672 B.4.4 Subject Alteration ...673 B.4.5 MIME Header Field Policies ...673 B.5 International Text Usage ...674 Japanese Character Issues ...675 B.6 Message Body and Attachments ...677 B.7 Message Subject ...678 B.8 ISO Tables ...679

Appendix C

Using Regular Expressions

683

C.1 General Issues ...684 C.1.1 Using Asterisks ...684 Using Question Marks ...685 C.1.2 Incorrect Usage in Regular Expressions ...685 C.2 Operators ...686 C.3 Character Class Operators ...687 C.4 Tutorial Examples ...690

Appendix D

Creating Custom Reports

693

D.1 Creating and Installing a New Report ...694 D.1.1 Summary of Steps ...694 D.1.2 Creating and Installing the Report ...694 D.1.3 Example SQL Server Script for Adding Reports ...696 D.2 Report Customization Section Selection ...698 D.3 Parameter Field Order in the Report ...699 D.4 Report Categories ...701

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Welcome to the Tumbleweed Email Firewall™ 6.2 Administrator’s Guide. This guide provides a description of the components, capabilities, and operation of Tumbleweed Email Firewall 6.2. It provides background, conceptual, and procedural information for planning your Tumbleweed Email Firewall installation, and provides instructions for setting up and configuring Email Firewall policies for your organization.

This preface contains the following sections:

Conventions Used in this Guide...xxvi Contact Information and Support ...xxvii

Preface

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Conventions Used in this Guide

The following type and style conventions are used in this guide.

Table P.1: Conventions

Convention Meaning

body text This font is used for regular body text.

Bold Bold blue text indicates a menu, button, text entry or icon choice.

Italics Italics indicate a table title, book title, or cross-reference.

Command The Courier New font indicates application code or computer generated text.

<locale> Angle brackets indicate a user-specified com-mand line parameter.

http://www.example.com Small blue print indicates a URL or email link for additional relevant information.

1., 2., 3., ... Bold blue numbers indicate steps in a proce-dure.

The Note icon signals additional relevant information.

The Warning icon signals important informa-tion that may affect the operainforma-tion of or may be a potential threat to the system.

The Tip icon signals a tip that may save time or effort.

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Contact Information and Support

The following modes of contact can be used for Tumbleweed Global Support assistance.

For Tumbleweed Global Support

If possible, log into the Tumbleweed product before contacting a Tumbleweed Global Support representative directly, and have the following information ready:

• Product version and Dynamic Anti-spam Update service filter version in use. (Select Status on the main menu and scroll to the License/version tab.)

• The text of the error or warning message.

• A description of the problem and attempts made to fix the problem. Please include your name, email address, company, and server URL in all correspondence.

Table P.2: Global Support Contact Information

Type of Contact Description

Global Support Online http://www.tumbleweed.com/en/support/ Global Support Email [email protected]

Global Support Helpline 650-216-2109 Global Support Request

Form

http://www.tumbleweed.com/dy/sup-port/request/request_support.php Customer Service,

License Keys and Ship-ping Orders

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For General Information

The following modes of contact can be used for general information.

Table P.3: General Contact Information

Type of Contact Description

World Wide Web Visit the Tumbleweed Web site for general informa-tion and current issues.

http://www.tumbleweed.com

Email Address Send email to the following address: [email protected]

Telephone Use the following telephone number for general inquiries:

650-216-2000

Postal Address Send regular mail to the following address: Tumbleweed Communications Corp. 700 Saginaw Drive

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Tumbleweed Email FirewallTM is a content security and policy management solution for Internet email. It integrates multiple protection modules, including access control, spam filtering, content filtering, attachment management, and virus and mobile code scanning to allow administrators to create and enforce SMTP email security policies across an organization.

Email Firewall 6.2 is the latest release in the Tumbleweed family of products. It is the email solution for enterprise communications. Email Firewall uses a modular architecture built around a Microsoft SQL Server database. Configuration data, policies, security certificates and keys, directory information, and message meta-data are stored in a central SQL Server database. This database is accessed by Email Firewall components, including one or more Policy Engines, SMTP relays, and other services, deployed on one or more (typically more) computers. With this easily scalable architecture, Email Firewall fits robustly into the enterprise network.

This chapter contains the following sections:

1.1 Intended Audience ... 2 1.2 Overview of Email Firewall 6.2 ... 3 1.3 Other Documentation ... 4

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1.1 Intended Audience

This guide is intended for the people who design, plan, and administer email messaging solutions. It outlines the capabilities of Tumbleweed Email Firewall, describes how it works, and provides instructions for deployment and effective use in today’s business organizations. This guide assumes a working familiarity with messaging systems, networking concepts, and server administration. This guide describes what the Tumbleweed Email Firewall is and how to use its features. Included are discussions of email security options, descriptions of the default policies and what they do, and examples designed to help you to understand how to create, apply, and test your own policies.

This guide also provides instructions for customizing Email Firewall policies specifically for your organization, and provides examples of such policies at work. Also included are instructions on maintenance administration, troubleshooting, and an overview of the Email Firewall reporting features.

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1.2 Overview of Email Firewall 6.2

Organizations use Tumbleweed Email Firewall for a variety of reasons. You can use Email Firewall to:

• exchange secure email

• protect against threats introduced by viruses and executable files • quarantine suspicious email

• reduce or eliminate spam and hoax traffic

• prevent leakage of sensitive and confidential information • establish conformance to corporate policy

• defer large messages to off-peak hours

• redirect messages to secure Tumbleweed Secure Messenger or IME servers.

• archive messages for a detailed audit trail of email communication The administrative functions of Tumbleweed Email Firewall support deployment and management of Email Firewall in large enterprises. The browser-based Web Admin component provides centralized administration of all of the Email Firewall components. Web Admin provides fully functional remote administration, authentication of administrators, and auditing of administrators’ actions. Administrator accounts are role-based to provide multiple levels of administration with granular access to sensitive controls or data. Secure access by multiple remote administrators with only the access privileges specifically granted provides a highly flexible overall enterprise security solution.

The modular, Microsoft SQL Server-based architecture allows Email Firewall to be deployed across multiple machines and in multiple remote locations. The SQL Server database management system enables enhanced throughput and centralized management of all Email Firewall data resources. Email Firewall configuration data, policies, certificates, directory information, event log data, and message meta-data are stored on a central SQL Server database server using its relational database.

Complete directory support allows policies to be applied globally, to groups, or to individual users. Information stored in LDAP-compliant directories can be easily imported and updated, and used to define to whom email usage policies apply.

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(TLS). Using PGP keys instead of certificates, OpenPGP security also enables email encryption and authentication. Mail can be digitally signed and encrypted by Email Firewall for an entire organization, for specified groups within the organization, or for individual users using either S/MIME or OpenPGP security. For more information on using Tumbleweed Email Firewall 6.2, see the Tumbleweed Email Firewall Help link located on each page in Web Admin. for more general information, visit the Tumbleweed Web site at

www.tumbleweed.com.

1.3 Other Documentation

For additional information about how to install, configure, and administer Email Firewall 6.2, see the following sources:

• Tumbleweed Email Firewall Help

The Help in the Tumbleweed Email Firewall Web Administration component contains context-sensitive information as well as a Table of Contents and Index available from every page. You can access the Help by clicking the Help button in the Web Admin UI. The Help also contains

troubleshooting information and step-by-step instructions for configuration tasks.

Tumbleweed Email Firewall 6.2 Release Notes

The Tumbleweed Email Firewall 6.2 Release Notes include prerequisites, hardware and software requirements, additional pre-installation and installation instructions, licensing information, new features since the EMF 6.1.1 release, and known limitations.

Tumbleweed Email Firewall 6.2 Installation and Upgrade Guide This document provides background and conceptual information for planning your Email Firewall installation, and provides detailed

installation instructions. It also provides instructions for upgrading EMF 6.1.1 to Email Firewall 6.2.

Tumbleweed Email Firewall Best Practices Guide

This document provides information about setting up Email Firewall optimally in large and complex environments. Included is information about SQL Server database setup, inbound and outbound email routing options, load balancing, and backup and failover strategies.

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Tumbleweed Email Firewall Anti-spam Best Practices Guide

This document provides additional information about setting up Email Firewall to combat spam.

Secure Redirect Administrator’s Guide

This Administrator’s Guide describes how to set up the Secure Redirect service to transparently redirect email to a Tumbleweed IME server. If you are installing Secure Messenger 6.2 with EMF 6.2, see the following sources for information about how to install, configure, and administer Secure Messenger 6.2:

Tumbleweed Secure Messenger 6.2 Release Notes

The Release Notes include up-to-date information related to hardware and software requirements, additional pre-installation instructions, licensing information and known limitations.

Tumbleweed Secure Messenger 6.2 Administrator’s Guide This guide presents an overview of Email Firewall and describes

configuration procedures and administration functions. It describes various use cases, and provides troubleshooting tips for operating Email Firewall 6.2.

Tumbleweed Secure Messenger Help

The online help in the Secure Messenger 6.2 Web Admin component contains context-sensitive information as well as a Table of Contents and Index available from every page.

You can access the Help by clicking the Help button in the Web Admin user interface. The Help also contains troubleshooting information and step-by-step instructions for configuration tasks.

Tumbleweed Secure Messenger 6.2 Developer’s Guide

This document provides information about branding the Secure Messenger end-user interfaces and integrating third party authentication

infrastructure.

Tumbleweed Email Firewall 6.2 Administrator's Guide This guide must be read and understood before deployment of Tumbleweed Secure Messenger 6.2 to obtain a comprehensive understanding of the entire Tumbleweed secure email solution.

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This chapter describes many of the features and tools in the Email Firewall Status page and the Setup links in Web Administration. Use this chapter as a road map for setting up, administering and monitoring Email Firewall.

This chapter also contains references to other sections of this guide containing more detailed information about each administrative task. This chapter contains the following sections:

2.1 Overview of Administrator Setup Tasks... 8 2.2 Administrative Security... 9 2.3 System Status ... 14 2.4 Setting Up Admin Roles and Accounts ... 21 2.5 Setting Up Relays ... 32 2.6 Setting Up Anti-virus and Anti-spam... 80 2.7 Setting Up Global Policy Settings ... 87 2.8 Setting Up Event Logging... 100 2.9 Other Setup Tasks ... 105

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2.1 Overview of Administrator Setup Tasks

Table 2.1 lists the tasks that should be performed to set up and administer Email Firewall in its entirety. It is recommend that you review the concepts and overview sections before performing these tasks.

Table 2.1: Overall Setup Tasks

Step Task Description and Procedures

1 Create additional administra-tors

2.4 Setting Up Admin Roles and Accounts on page 21

2 (Optional) Set up Centralized

Event Logging and Reporting

2.8.2 Setting Up Centralized Event Logging and Report-ing on page 101

3 Set up relays 2.5 Setting Up Relays on page 32

4 Set up global policy settings 2.7 Setting Up Global Policy Settings on page 87

5 Set up the Updates 2.6 Setting Up Anti-virus and Anti-spam on page 80

6 Set up the Queues 3.2 Setting Up Message Queues on page 116

7 Set up Personal Quarantine Manager

3.7 Using Personal Quarantine Manager on page 142

8 Set up the Dynamic Anti-spam Service

7.2 Dynamic Anti-spam Service Overview on page 332

9 Set up the Event Log 4.1 Setting Up Email Firewall Event Logging on page 186

10 Set up the Directory 10.2 Setting Up LDAP Directory Imports on page 534

11 Set up Security 9.1 Setting Up Email Firewall Security on page 430

12 Set up Policies 6.1 Introduction to Policy Building on page 256

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2.2 Administrative Security

There are three components of Email Firewall Web Administration security: • Authentication - the process of verifying the identity of the user.

• Authorization - the process of determining whether the user is permitted to view a specific function or perform a specific action within the system. • Auditing - the process of tracking changes and attempted changes to the

system.

The Email Firewall program allows the first two components to be defined when setting up administrative roles and accounts. Audit logs provide data for the third. These features provide enterprise-wide administrative control in a multiple-server, multiple-administrator environment. Instructions for setting up administrator roles and accounts can be found in 2.4 Setting Up Admin Roles and Accounts on page 21, and also in the Email Firewall Help.

2.2.1

Web Administration Access Controls

Email Firewall provides multiple levels of administration. This design allows you to define different administrative capabilities for different components and allows the Email Firewall Web Admin environment to be partitioned so that multiple people in the organization can manage different subsets of the system. Administrative access is defined by Admin Roles and Admin Accounts. Admin Roles grant access to the capabilities defined by that role. An Admin Account can be granted only one Admin Role. Based on the capabilities assigned to an Admin Role, an administrator can view/modify only the subset of the Email Firewall system allowed by the role’s capabilities. An administrator can perform only the subset of the administrative tasks allowed by the role’s capabilities.

At least one administrator must be assigned all capabilities in order to have an administrator who can manage the whole system, including creating additional Admin Roles and Accounts. Instructions for setting up Admin Roles and Admin

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Accounts can be found in 2.4 Setting Up Admin Roles and Accounts on page 21, and also in the Email Firewall Help.

2.2.2

Logging In

During Email Firewall installation, an administrator account consisting of name and password is set up. This default admin account with SuperAdmin role is

automatically granted the necessary privileges to set up additional administrator accounts and to administer Email Firewall. For instructions on creating additional admin accounts, see 2.4.3 Creating New Administrator Accounts on page 29.

To administer Email Firewall you must login to Email Firewall Web Admin. To access the login page, open your browser and type one of the following URLs in the browser address field:

To login to Email Firewall on a secure server (using a secure server is recom-mended):

https://<machine name>/emfadmin

To login to Email Firewall on a non-secure server:

http://<machine name>/emfadmin

Setting Up Secure Login

To setup Web Admin so that SSL (https) is required:

For the remainder of this chapter, functions are described assuming the administrator has full administrative privileges unless otherwise noted.

The Email Firewall Web Admin component requires the use of JavaScript. When using Internet Explorer, the Active Scripting Option must be enabled. See the Email Firewall

6.2 Installation and Upgrade Guide for instructions. Pop-up

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3. Click Internet Information Services and expand it.

4. Right-click the Default Web Site and select Properties.

5. Select the Directory Security tab.

6. In the Secure communications group box, click Edit.

7. Mark the Require secure channel (SSL) checkbox.

8. Optionally mark the Require 128-bit encryption checkbox.

9. Click Save.

When the login page opens, see Figure 2.1, type your Username and Password

in the fields and click Login. While logged in you can customize your account

preferences, including identity, password, and how many lines are displayed in your browser pages. For instructions, see 2.4.4 Preferences on page 31. Using multiple browser sessions is supported. However, you should start a new instance of the browser to do so. Do not attempt to open multiple browser windows using the same Web Administration session.

Figure 2.1: Login Page EMF

For security reasons the Web Administration component has a time-out feature. After 60 minutes of inactivity, you are automatically logged out and must log in again to continue.

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2.2.3

Main Menu

When you are logged into Web Administration, you will see the name of the SQL server on which Web Administration database resides. This server name displays on the top left of the page under the product name. Under the server name is the main menu. Each main menu item is the name of a major component or administrative tool. See Figure 2.2.

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Figure 2.2: Main Menu Overview

Click any menu item to open its main page.

The sections in this chapter:

• describe the Email Firewall page accessed by the menu item.

• describe the functions available from that page.

• when appropriate, refer you to other sec-tions of this guide for more detailed infor-mation.

The title bar at the top of every page shows the navigation path used to reach the open page. Each underlined page name is a link to that page. The last item is the name of the page you are viewing. To return to a previous page, click its underlined name in the path.

Note: The browser Back, Forward, and

Refresh buttons should not be used in Email Firewall Web Admin. Use the main menu and links in the pages to navigate.

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2.3 System Status

The System Status page is displayed on login. This page contains the Info and Alerts, Message Queues and Email Firewall Services tabs. A review of the

information on these tabs alerts you to the current Email Firewall operating status.

While working with Email Firewall, click Status to return to the Status page.

2.3.1

Info and Alerts Status

Thistab contains the Product version and its build number, and if installed, the

version information for all Dynamic Anti-spam Service (DAS) Filter and Virus Pattern along with date and time of the lastest update. If installed, this tab also contains the version and build number for either Secure Messenger or Secure Redirect depending on which secure email component is installed. If you need to contact your Tumbleweed Global Support representative you will be requested to provide this information. See Figure 2.3.

Underlined headings and text in the Email Firewall Web Admin pages are links to the described page.

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The Email Firewall Service Update heading provides a link to a page that provides

all available Email Firewall updates (versions, patches or hot fixes) for this system.

The Email Firewall Knowledge Base heading provides a link to the Tumbleweed Knowledge Portal where you access Tumbleweed Knowledge Base articles. This page requires a user name and password. To obtain a user name and password, click the New users click here to register for access link.

The Email Firewall Services heading provides a quick reference to the status of

the services and a convenient link to the Email Firewall Services tab.

The Errors & Warnings heading lists the number of errors and warnings

generated during the last 24 hours. Click the link after Errors or Warnings to

open the Event Log to view, filter and sort these events. The Event Log can be filtered so that only those warning and error events you select are shown in the Event Log. For more information on creating and configuring Event Log filters, see 4.2 Searching the Event Log on page 190.

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Alerts are displayed for the following conditions:

• All Outbound Mail Currently Stopped This alert is displayed when:

• the Stop All Outbound Mail checkbox is marked on the Setup > Relay

General Settings page.

• the value for Maximum Outbound Connections is set to 0 on the

Setup > Relay General Settings page. • All Inbound Mail Currently Stopped

This alert is displayed when:

• the Reject All Inbound Connections checkbox is marked on the Setup > Relay General Settings page.

• the value for Maximum Inbound Connections is set to 0 on the Setup > Relay General Settings page.

• if the Dynamic Anti-spam Service is not installed: the Stop the SMTP relay from accepting incoming messages checkbox is marked

(in the Inbound queue setup page) and the Inbound queue threshold

is triggered. (The Triggered status is displayed on the Message

Queues tab when the queue grows to or exceeds the specified number of messages.)

• if the Dynamic Anti-spam Service is installed: the Stop the SMTP relay from accepting incoming messages checkbox is marked (in the Spam Analysis queue setup page) and the Spam Analysis queue

threshold is triggered. (The Triggered status is displayed on the

Message Queues tab when the queue grows to or exceeds the specified number of messages.)

• Mail Not Being Routed through Policy Engine

This alert is displayed when the Route messages through policy engine (and spam analysis engine if installed and running) checkbox is unmarked on the Setup > Relay General Settings page.

To resolve these alerts, check the settings as applicable. • Expiration of Evaluation License

This alert is displayed when:

• The Email Firewall evaluation license is about to expire.

After expiration, Email Firewall stops all content, spam and virus filtering of incoming and outgoing mail. Email Firewall will

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• The Dynamic Anti-spam Service evaluation license is about to expire.

After expiration, the Spam Analysis Engine stops analyzing and tagging messages with DAS message properties or X-headers. Policies that depend on the DAS tagging will not work. To resolve these alerts, obtain a full license from your Global Support Representative.

• When the anti-virus patterns files are more than 7 days old. • When the anti-spam filter files are more than 7 days old.

2.3.2

Message Queues Status

The Message Queues tab displays the number of messages currently in the Email Firewall mail queues. See Figure 2.4.

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The queues contain messages that are inbound to or outbound from Email Firewall, messages awaiting preprocessing by the Dynamic Anti-spam Service (if installed), awaiting redirection to a secure Tumbleweed IME server (if installed), awaiting preprocessing by the Secure Messenger (if installed), awaiting retry, and messages that were quarantined, detained, deferred, archived, returned or could not be delivered. The Partition queue contains messages requiring delivery to multiple recipients.

For more detailed information on the queues, including how to set them up, see 3.2 Setting Up Message Queues on page 116 and the Email Firewall Help. For a more detailed description of each queue, see Table 3.1 on page 116.

Email Firewall is an active system and the Message Count displayed shows the

number of messages in the queues when the System Status page was last accessed. The current message count may differ from the number displayed. Use Refresh to update the page to show the most current message count.

From the Message Queues tab you can click an underlined queue name to access

that queue’s main page and view the messages in that queue. Although the

Return, Archive and Partition queues are not configurable, it is useful to occasionally note the number of messages in those queues. An excessive number of messages in those queues could indicate a processing problem that should be investigated.

If you notice a large number of messages in the Quarantine Queues, see 3.5.3

Checking the Quarantine Queue for Inbound Messages on page 135 for troubleshooting information.

The Queue Counts tab displays either the Redirect link or the Secure Messenger link depending on whether you have installed Tumbleweed’s IME server or Secure Messenger to securely deliver your outbound email messages. Figure 2.4 shows the Redirect link.

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2.3.3

Email Firewall Services Status

The Email Firewall Services tab lists the services that are currently running and

those that were running at some point in the past when Web Administration was running. This tab shows the current or past operating status of each service, the host name each service is running on (if applicable), and if available, its IP address. If a service is not currently running or has been uninstalled, a Remove

button appears in its Action column.

Clicking Remove deletes that service from the Email Firewall Services tab list.

However, Remove does not delete or uninstall the service from Email Firewall; it only removes its row from the list on the Email Firewall Services tab. Use the Remove button if you do not want to view the Email Firewall services that are

not currently running or that have been uninstalled. Figure 2.5 shows an example of the Email Firewall Services tab.

Figure 2.5 shows services as they would appear if installed

on the same host. In complex environments it is expected that some of these services will be deployed on different hosts.

For the services related to the secure delivery of email messages, either the Email Firewall Secure Redirect service or the Email Firewall Secure Messenger service displays within the Email Firewall Services tab depending on which component is installed, if at all.

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Click Refresh to update the information displayed on the tab.

Figure 2.5: System Status Email Firewall Services Tab

If you have installed the Email Firewall SMTP Relay service Inbound partition only, you may not see the SMTP Relay Service status displayed on the Email Firewall Services tab until after the Inbound relay has received messages. This is because the relay does not establish a connection with the database until after the Inbound relay is in use.

If you have installed the Secure Messenger with Email Firewall, the Email Firewall Secure Messenger service displays on the Email Firewall Services tab instead of the Email Firewall Secure Redirect service, which is currently shown in Figure 2.5.

References

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