[MS-DRM]:
Digital Rights Management License Protocol
Intellectual Property Rights Notice for Open Specifications Documentation
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Revision Summary
Date / Revision History / Revision Class / Comments5/11/2007 / 0.1 / New / Version 0.1 release
8/10/2007 / 1.0 / Major / Updated and revised the technical content.
9/28/2007 / 1.0.1 / Editorial / Changed language and formatting in the technical content.
10/23/2007 / 1.0.2 / Editorial / Changed language and formatting in the technical content.
11/30/2007 / 1.0.3 / Editorial / Changed language and formatting in the technical content.
1/25/2008 / 1.0.4 / Editorial / Changed language and formatting in the technical content.
3/14/2008 / 2.0 / Major / Updated and revised the technical content.
5/16/2008 / 2.0.1 / Editorial / Changed language and formatting in the technical content.
6/20/2008 / 2.0.2 / Editorial / Changed language and formatting in the technical content.
7/25/2008 / 2.0.3 / Editorial / Changed language and formatting in the technical content.
8/29/2008 / 2.0.4 / Editorial / Changed language and formatting in the technical content.
10/24/2008 / 2.1 / Minor / Clarified the meaning of the technical content.
12/5/2008 / 2.1.1 / Editorial / Editorial Update.
1/16/2009 / 2.1.2 / Editorial / Changed language and formatting in the technical content.
2/27/2009 / 2.2 / Minor / Clarified the meaning of the technical content.
4/10/2009 / 3.0 / Major / Updated and revised the technical content.
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7/2/2009 / 5.0 / Major / Updated and revised the technical content.
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9/25/2009 / 5.1 / Minor / Clarified the meaning of the technical content.
11/6/2009 / 5.1.1 / Editorial / Changed language and formatting in the technical content.
12/18/2009 / 6.0 / Major / Updated and revised the technical content.
1/29/2010 / 6.1 / Minor / Clarified the meaning of the technical content.
3/12/2010 / 6.1.1 / Editorial / Changed language and formatting in the technical content.
4/23/2010 / 7.0 / Major / Updated and revised the technical content.
6/4/2010 / 8.0 / Major / Updated and revised the technical content.
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8/27/2010 / 9.0 / None / No changes to the meaning, language, or formatting of the technical content.
10/8/2010 / 9.0 / None / No changes to the meaning, language, or formatting of the technical content.
11/19/2010 / 9.0 / None / No changes to the meaning, language, or formatting of the technical content.
1/7/2011 / 9.0 / None / No changes to the meaning, language, or formatting of the technical content.
2/11/2011 / 9.0 / None / No changes to the meaning, language, or formatting of the technical content.
3/25/2011 / 10.0 / Major / Updated and revised the technical content.
5/6/2011 / 11.0 / Major / Updated and revised the technical content.
6/17/2011 / 11.1 / Minor / Clarified the meaning of the technical content.
9/23/2011 / 11.1 / None / No changes to the meaning, language, or formatting of the technical content.
12/16/2011 / 12.0 / Major / Updated and revised the technical content.
3/30/2012 / 12.0 / None / No changes to the meaning, language, or formatting of the technical content.
7/12/2012 / 12.0 / None / No changes to the meaning, language, or formatting of the technical content.
10/25/2012 / 12.0 / None / No changes to the meaning, language, or formatting of the technical content.
1/31/2013 / 13.0 / Major / Updated and revised the technical content.
8/8/2013 / 14.0 / Major / Updated and revised the technical content.
11/14/2013 / 15.0 / Major / Updated and revised the technical content.
2/13/2014 / 15.0 / None / No changes to the meaning, language, or formatting of the technical content.
5/15/2014 / 15.0 / None / No changes to the meaning, language, or formatting of the technical content.
6/30/2015 / 16.0 / Major / Significantly changed the technical content.
10/16/2015 / 16.0 / None / No changes to the meaning, language, or formatting of the technical content.
7/14/2016 / 17.0 / Major / Significantly changed the technical content.
Table of Contents
1Introduction
1.1Glossary
1.2References
1.2.1Normative References
1.2.2Informative References
1.3Overview
1.3.1Digital Rights Management Version 1
1.3.2Digital Rights Management Version 7
1.3.3Digital Rights Management Version 11
1.4Relationship to Other Protocols
1.5Prerequisites/Preconditions
1.6Applicability Statement
1.7Versioning and Capability Negotiation
1.8Vendor-Extensible Fields
1.9Standards Assignments
2Messages
2.1Transport
2.2Message Syntax
2.2.1Common Data Types and Algorithms
2.2.1.1Base64 Encoding
2.2.1.1.1Base64 Mapping Table
2.2.1.1.2Example: Base64 Encoding of 3 Bytes
2.2.1.1.3Base64 and DRM
2.2.1.2Cryptographic Parameters
2.2.1.3Cryptographic Keys
2.2.1.4PK
2.2.1.5PKCERT
2.2.1.6PUBKEY
2.2.1.7LicenseToSend
2.2.2DRM Version 1 Data Types
2.2.2.1DRM Version 1 License Request
2.2.2.2DRM Version 1 License Response
2.2.2.3DRM Version 1 License Format
2.2.2.3.1CERT
2.2.2.3.2CERTDATA
2.2.2.3.3CERTIFIED_LICENSE
2.2.2.3.4LICENSE
2.2.2.3.5LICENSEDATA
2.2.3DRM Version 7 Data Types
2.2.3.1DRM Version 7 License Request
2.2.3.1.1Silent and Nonsilent Requests
2.2.3.1.1.1Silent Requests
2.2.3.1.1.2Nonsilent Requests
2.2.3.1.2HTTP POST Headers
2.2.3.1.3XML Schema for Version 7 License Request
2.2.3.1.3.1ACTION
2.2.3.1.3.2APPSECURITY
2.2.3.1.3.3CLIENTID (Element)
2.2.3.1.3.4CLIENTID (Structure)
2.2.3.1.3.5CLIENTVERSION
2.2.3.1.3.6DRMKVERSION
2.2.3.1.3.7REVOCATIONINFO
2.2.3.1.3.8SECURITYVERSION
2.2.3.1.3.9SUBJECTID1
2.2.3.1.3.10SUBJECTID2
2.2.3.1.3.11V1CHALLENGE
2.2.3.1.3.12WMRMHEADER
2.2.3.2DRM Version 7 License Response
2.2.3.2.1Silent Acquisition
2.2.3.2.2Nonsilent Acquisition
2.2.3.2.3Errors
2.2.3.2.4XML Schema for Version 7 License Response
2.2.3.2.4.1DRM Version 1 License Format Within a Version 7 License Response
2.2.3.2.4.2DRM Version 7 License Format
2.2.3.2.5ACTION
2.2.3.2.6ANALOGVIDEO
2.2.3.2.7CERTIFICATE
2.2.3.2.8CERTIFICATECHAIN
2.2.3.2.9COMPRESSEDDIGITALAUDIO
2.2.3.2.10COMPRESSEDDIGITALVIDEO
2.2.3.2.11CONDITION When Used Under the ONACTION, ONSELECT, and ONSTORE Elements
2.2.3.2.12CONDITION When Used Under the CONTENTREVOCATION/DATA Element
2.2.3.2.13CONTENTPUBKEY
2.2.3.2.14CONTENTREVOCATION
2.2.3.2.15COPY
2.2.3.2.16ENABLINGBITS
2.2.3.2.17Events in DRM Licenses
2.2.3.2.18Expressions in DRM Licenses
2.2.3.2.18.1Identifier
2.2.3.2.18.2Function Symbol
2.2.3.2.18.3Constant
2.2.3.2.18.4Variable
2.2.3.2.18.5Final Value
2.2.3.2.19Operators in DRM Expressions
2.2.3.2.19.1Operator Behavior
2.2.3.2.19.2Operator Precedence
2.2.3.2.20Data Types in DRM Expressions
2.2.3.2.20.1DATETIME Data Type
2.2.3.2.20.2LONG Data Type
2.2.3.2.20.3STRING Data Type
2.2.3.2.20.4Casting Data Types
2.2.3.2.21ISSUEDATE
2.2.3.2.22KID
2.2.3.2.23LICENSESERVERPUBKEY
2.2.3.2.24LICENSORINFO
2.2.3.2.25LID
2.2.3.2.26META
2.2.3.2.27ONACTION
2.2.3.2.28ONCLOCKROLLBACK
2.2.3.2.29ONSELECT
2.2.3.2.30ONSTORE
2.2.3.2.31Predefined Functions in DRM Expressions
2.2.3.2.32Predefined Variables in DRM Expressions
2.2.3.2.33PRIORITY
2.2.3.2.34PUBKEY
2.2.3.2.35RESTRICTIONS
2.2.3.2.36REV_INFO
2.2.3.2.37REVOCATION
2.2.3.2.38RevocationList
2.2.3.2.39SEQUENCENUMBER
2.2.3.2.40SIGNATURE When Used Under the CONTENTREVOCATION or LICENSORINFO Element
2.2.3.2.41SIGNATURE When Used Under the ENABLINGBITS Element
2.2.3.2.42UNCOMPRESSEDDIGITALAUDIO
2.2.3.2.43UNCOMPRESSEDDIGITALVIDEO
2.2.3.2.44VALUE
2.2.3.2.45WMDRMRLVICERTCHAIN
2.2.3.2.46WMDRMRLVIHEAD
2.2.3.2.47WMDRMRLVISIGNATURE
2.2.3.2.48WMDRMRLVIVERSION
2.2.4DRM Version 11 Data Types
2.2.4.1DRM Version 11 License Request
2.2.4.1.1MACHINECERTIFICATE
2.2.4.1.2REVINFO
2.2.4.1.3ACTION
2.2.4.2DRM Version 11 License Response
3Protocol Details
3.1Client Details
3.1.1Abstract Data Model
3.1.2Timers
3.1.3Initialization
3.1.4Higher-Layer Triggered Events
3.1.5Message Processing Events and Sequencing Rules
3.1.5.1DRM Version 1 Client Message Processing Events and Sequencing Rules
3.1.5.1.1Request Behavior
3.1.5.1.2Response Behavior
3.1.5.2DRM Version 7 Client Message Processing Events and Sequencing Rules
3.1.5.2.1Request Behavior
3.1.5.2.2Response Behavior
3.1.5.2.2.1LICENSERESPONSE.LICENSE nodes
3.1.5.2.2.2LICENSERESPONSE.Revocation nodes
3.1.5.3DRM Version 11 Client Message Processing Events and Sequencing Rules
3.1.5.3.1Request Behavior
3.1.5.3.2Response Behavior
3.1.6Timer Events
3.1.7Other Local Events
3.2Server Details
3.2.1Abstract Data Model
3.2.1.1TransmitLicensesToClient
3.2.2Timers
3.2.3Initialization
3.2.3.1Retrieving Revocation Data from the Enrollment Server
3.2.3.1.1Client Certificate White List
3.2.3.1.2Revocation Information List
3.2.3.1.3Certificate Revocation List
3.2.4Higher-Layer Triggered Events
3.2.5Message Processing Events and Sequencing Rules
3.2.5.1DRM Version 1 Server Message Processing Events and Sequencing Rules
3.2.5.2DRM Version 7 Server Message Processing Events and Sequencing Rules
3.2.5.3DRM Version 11 Server Message Processing Events and Sequencing Rules
3.2.6Timer Events
3.2.7Other Local Events
4Protocol Examples
4.1DRM Version 1 License Request Example
4.2DRM Version 1 License Response Example
4.3DRM Version 7 License Request Example
4.4DRM Version 7 License Response Example
4.5DRM Version 7 Nonsilent License Response Example
4.6DRM Version 11 License Request Example
4.7DRM Version 11 License Response Example
5Security
5.1Security Considerations for Implementers
5.2Index of Security Parameters
6Appendix A: Product Behavior
7Change Tracking
8Index
1Introduction
The Windows Media Digital Rights Management (WMDRM): License Protocol provides secure distribution, promotion, and sale of digital media content. The protocol is used to acquire licenses for Windows Media content protected using Digital Rights Management Version 1, Digital Rights Management Version 7, or Digital Rights Management Version 11 technologies.
Sections 1.5, 1.8, 1.9, 2, and 3 of this specification are normative. All other sections and examples in this specification are informative.
1.1Glossary
This document uses the following terms:
ASCII: The American Standard Code for Information Interchange (ASCII) is an 8-bit character-encoding scheme based on the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that work with text. ASCII refers to a single 8-bit ASCII character or an array of 8-bit ASCII characters with the high bit of each character set to zero.
base64 encoding: A binary-to-text encoding scheme whereby an arbitrary sequence of bytes is converted to a sequence of printable ASCII characters, as described in [RFC4648].
certificate: A certificate is a collection of attributes (1) and extensions that can be stored persistently. The set of attributes in a certificate can vary depending on the intended usage of the certificate. A certificate securely binds a public key to the entity that holds the corresponding private key. A certificate is commonly used for authentication (2) and secure exchange of information on open networks, such as the Internet, extranets, and intranets. Certificates are digitally signed by the issuing certification authority (CA) and can be issued for a user, a computer, or a service. The most widely accepted format for certificates is defined by the ITU-T X.509 version 3 international standards. For more information about attributes and extensions, see [RFC3280] and [X509] sections 7 and 8.
certificate revocation: The process of invalidating a certificate. For more information, see [RFC3280] section 3.3.
certificate revocation list (CRL): A list of certificates that have been revoked by the certification authority (CA) that issued them (that have not yet expired of their own accord). The list must be cryptographically signed by the CA that issues it. Typically, the certificates are identified by serial number. In addition to the serial number for the revoked certificates, the CRL contains the revocation reason for each certificate and the time the certificate was revoked. As described in [RFC3280], two types of CRLs commonly exist in the industry. Base CRLs keep a complete list of revoked certificates, while delta CRLs maintain only those certificates that have been revoked since the last issuance of a base CRL. For more information, see [X509] section 7.3, [MSFT-CRL], and [RFC3280] section 5.
curly braced GUID string: The string representation of a 128-bit globally unique identifier (GUID) using the form {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX}, where X denotes a hexadecimal digit. The string representation between the enclosing braces is the standard representation of a GUID as described in [RFC4122] section 3. Unlike a GUIDString, a curly braced GUID string includes enclosing braces.
Digital Rights Management (DRM): A set of technologies that provides control over how a given piece of protected content can be used.
elliptic curve cryptography (ECC): A public-key cryptosystem that is based on high-order elliptic curves over finite fields. For more information, see [IEEE1363].
globally unique identifier (GUID): A term used interchangeably with universally unique identifier (UUID) in Microsoft protocol technical documents (TDs). Interchanging the usage of these terms does not imply or require a specific algorithm or mechanism to generate the value. Specifically, the use of this term does not imply or require that the algorithms described in [RFC4122] or [C706] must be used for generating the GUID. See also universally unique identifier (UUID).
Hypertext Transfer Protocol (HTTP): An application-level protocol for distributed, collaborative, hypermedia information systems (text, graphic images, sound, video, and other multimedia files) on the World Wide Web.
Hypertext Transfer Protocol Secure (HTTPS): An extension of HTTP that securely encrypts and decrypts web page requests. In some older protocols, "Hypertext Transfer Protocol over Secure Sockets Layer" is still used (Secure Sockets Layer has been deprecated). For more information, see [SSL3] and [RFC5246].
little-endian: Multiple-byte values that are byte-ordered with the least significant byte stored in the memory location with the lowest address.
RC4: A variable key-length symmetric encryption algorithm. For more information, see [SCHNEIER] section 17.1.
revocation: The process of invalidating a certificate. For more details, see [RFC3280] section 3.3.
Secure Digital Music Initiative (SDMI): An initiative to establish technology specifications that would protect the playing, storing. and distributing of digital music. These specifications are currently obsolete.
SHA-1 hash: A hashing algorithm as specified in [FIPS180-2] that was developed by the National Institute of Standards and Technology (NIST) and the National Security Agency (NSA).
transport layer: The fourth layer in the Open Systems Interconnection (OSI) architectural model as defined by the International Organization for Standardization (ISO). The transport layer provides for transfer correctness, data recovery, and flow control. The transport layer responds to service requests from the session layer and issues service requests to the network layer.
Uniform Resource Identifier (URI): A string that identifies a resource. The URI is an addressing mechanism defined in Internet Engineering Task Force (IETF) Uniform Resource Identifier (URI): Generic Syntax [RFC3986].
XML: The Extensible Markup Language, as described in [XML1.0].
MAY, SHOULD, MUST, SHOULD NOT, MUST NOT: These terms (in all caps) are used as defined in [RFC2119]. All statements of optional behavior use either MAY, SHOULD, or SHOULD NOT.
1.2References
Links to a document in the Microsoft Open Specifications library point to the correct section in the most recently published version of the referenced document. However, because individual documents in the library are not updated at the same time, the section numbers in the documents may not match. You can confirm the correct section numbering by checking the Errata.
1.2.1Normative References
We conduct frequent surveys of the normative references to assure their continued availability. If you have any issue with finding a normative reference, please contact . We will assist you in finding the relevant information.
[MS-DTYP] Microsoft Corporation, "Windows Data Types".
[MS-ERREF] Microsoft Corporation, "Windows Error Codes".
[RC4-ENCRYPT] Schneier, B., "Applied Cryptography: Protocols, Algorithms, and Source Code in C", 2nd edition, Wiley, 1996, ISBN-10: 041117099 and ISBN-13: 978-0471117094.
[RFC2045] Freed, N., and Borenstein, N., "Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies", RFC 2045, November 1996,
[RFC2109] Kristol, D., and Montulli, L., "HTTP State Management Mechanism", RFC 2109, February 1997,
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997,
[RFC2616] Fielding, R., Gettys, J., Mogul, J., et al., "Hypertext Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999,
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000,
[RFC2821] Klensin, J., "Simple Mail Transfer Protocol", RFC 2821, April 2001,
[RFC3275] Eastlake III, D., Reagle, J., and Solo, D., "(Extensible Markup Language) XML-Signature Syntax and Processing", RFC 3275, March 2002,
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data Encodings", RFC 4648, October 2006,
[RSAFAQ] RSA Laboratories, "Frequently Asked Questions About Today's Cryptography, Version 4.1", May 2000,
[XMLSCHEMA1/2] Thompson, H., Beech, D., Maloney, M., and Mendelsohn, N., Eds., "XML Schema Part 1: Structures Second Edition", W3C Recommendation, October 2004,
[XMLSCHEMA2/2] Biron, P., and Malhotra, A., Eds., "XML Schema Part 2: Datatypes Second Edition", W3C Recommendation, October 2004,
[XML] World Wide Web Consortium, "Extensible Markup Language (XML) 1.0 (Fourth Edition)", W3C Recommendation 16 August 2006, edited in place 29 September 2006,
1.2.2Informative References
[CAECCRYPT] Barbosa, M., Moss, A., and Page, D., "Compiler Assisted Elliptic Curve Cryptography",
[ELLIPTICCURVE-DSA] Farkas, S., "Elliptic Curve DSA", January 2007,
[ELLIPTICCURVE] RSA Laboratories, "Overview of Elliptic Curve Cryptosystems", June 1997,
[MSDN-WMRMHEADOBJ] Microsoft Corporation, "WMRMHeader Object",
[NSPCPW] Perlman, R., Speciner, M., and Kaufman, C., "Network Security: Private Communication in a Public World", New York, 1980, ASIN: B000N7EJQQ.
[SCHNEIER] Schneier, B., "Applied Cryptography, Second Edition", John Wiley and Sons, 1996, ISBN: 0471117099,
[X9.62] American National Standards Institute, "Public Key Cryptography for the Financial Services Industry, The Elliptic Curve Digital Signature Algorithm (ECDSA)", ANSI X9.62:2005, 2005,
Note There is a charge to download the specification.
1.3Overview
Digital Rights Management (DRM) version 1, version 7, and version 11 provide a means of acquiring a license for Windows Media content.
When using Digital Rights Management Version 1, the client generates a license request and sends it to a license server as an HTTP GET request. The server receives the GET request and returns the license to the client embedded within an HTML page.
Digital Rights Management Version 7 uses a packet containing a license request in extensible markup language (XML) format and is sent using an HTTP POST request. The server responds with an XML packet containing any number and combination of version 1 and version 7 licenses.