WEB401

Security Practices for Web Services (Part 2)

Keith BallingerProgram ManagerXML MessagingMicrosoft Corporation

Agenda

Trusting clients and servicesEnabling a manageable B2B infrastructure

Creating a security contextFaster security performance

Authoring security policyRemoving the need for writing a lot of security code

Trust

Relationships and identityHow do I prove who I am?

Who can vouch for me?

How do you know you can trust him?

These questions are answered with signed security tokens

WS-Trust defines a protocol for issuing and obtaining security tokens

Trust

Several models for issuing tokens

Client obtains token

Service obtains token for client

Etc…

Client

Token Issuer

Service

Client Service

TokenIssuer 2

TokenIssuer 1

Client

TokenIssuer

Service

Trust

Requesting a security token (RST)<RequestSecurityToken>

<TokenType>...</TokenType> </RequestSecurityToken>

Issuing a security token (RSTR)<RequestSecurityTokenResponse>

<TokenType /> <wsp:AppliesTo />

<RequestedSecurityToken/> <RequestedProofToken /> </RequestSecurityTokenResponse>

Trust

RST is usually signed with a token the token issuer trusts

RSTR issues new tokenProof of possession token can also returned

This token includes a key that the requestor can use to prove he’s allowed to use the issued token

Issuing a custom Issuing a custom XML-based security XML-based security tokentoken

demodemo

Secure conversation

Token issuing can also occur between two parties

Client

ServiceAnd

TokenIssuer

Typically, this is done to create higher performance security processing

WS-SecureConversation is an example

Secure conversation

WS-SecureConversation details how to issue a SecurityContextToken

In WSE, this lightweight token takes the place of a more processing intensive token

Client

ServiceAnd

TokenIssuer

Request for SCTRequest for SCT

SCT Issued to clientSCT Issued to client

Series of messages Series of messages

signed with issued SCTsigned with issued SCT

Building a Secure Building a Secure Conversation with Conversation with WSEWSE

demodemo

Policy

Beyond what WSDL provides, what else is needed to describe a Web service?

Security requirements

Reliable messaging assurances

Protocol versioning

Etc…

These other attributes of a service can be described with WS-Policy

XML-base language

Complex: <Or>, <ExactlyOne>, etc…

Policy

<wsp:Policy

wsu:Id="message-age">

<wsse:MessageAge wsp:Usage="wsp:Required" Age="5“

/>

</wsp:Policy>

Security policy

WS-SecurityPolicy specifies the assertions for expressing requirements related to WS-Security

<Integrity>

<Confidentiality>

<SecurityToken>Can be embedded inside the other two

Security Policy

<wsp:Policy wsu:Id="signed-body-x509"> <wsse:Integrity wsp:Usage="wsp:Required" > <TokenInfo> <SecurityToken> <TokenType>X509v3</TokenType> </SecurityToken> </TokenInfo> <MessageParts

Dialect="http://schemas.xmlsoap.org/2002/12/wsse#part"> wsp:Body() </MessageParts> </Integrity> </wsp:Policy>

Role-based security

IPrincipal is the .NET interface for role-based authoriztion

bool IsInRole(String str)

SecurityToken.PrincipalImplementation of IPrincipal

Automatically set for UsernameToken and KerberosSecurityToken

Call method explicitly or use Policy<wse:Role value=“role” />

Role-Based Role-Based Authorization using Authorization using Security PolicySecurity Policy

demodemo

Suggested Reading And Resources

The tools you need to put technology to work!The tools you need to put technology to work!

TITLETITLE AvailableAvailable

Writing Secure Code, Second Writing Secure Code, Second Edition:0-7356-1722-8Edition:0-7356-1722-8 TodayToday

Microsoft Press books are 20% off at the TechEd Bookstore

Also buy any TWO Microsoft Press books and get a FREE T-Shirt

Community Resources

Community Resourceshttp://www.microsoft.com/communities/default.mspx

Most Valuable Professional (MVP)http://www.mvp.support.microsoft.com/

NewsgroupsConverse online with Microsoft Newsgroups, including Worldwidehttp://www.microsoft.com/communities/newsgroups/default.mspx

User GroupsMeet and learn with your peershttp://www.microsoft.com/communities/usergroups/default.mspx

evaluationsevaluations

© 2003 Microsoft Corporation. All rights reserved.© 2003 Microsoft Corporation. All rights reserved.This presentation is for informational purposes only. MICROSOFT MAKES NO WARRANTIES, EXPRESS OR IMPLIED, IN THIS SUMMARY.This presentation is for informational purposes only. MICROSOFT MAKES NO WARRANTIES, EXPRESS OR IMPLIED, IN THIS SUMMARY.