Widevine

Widevine was created by Seattle-based Internet Direct Media in 1999 as Widevine Cypher.{{Cite web |url=https://www.forbes.com/sites/oliverchiang/2010/12/03/google-buys-digital-video-company-widevine-building-up-video-on-demand-service/ |title=Google Buys Digital Video Company Widevine, Building Up Video On-Demand Service |date=December 3, 2010 |last=Chiang |first=Oliver |work=Forbes |access-date=March 13, 2023}} The company, founded by executive Brian Baker and cryptography researcher Jeremy Horwitz, changed its name to Widevine Technologies.{{Cite web |url=https://www.seattletimes.com/business/google-acquires-widevine/ |title=Google acquires Widevine |date=December 3, 2010 |last=Dudley |first=Brier |work=The Seattle Times |access-date=March 13, 2023}}{{Cite web |url=https://adage.com/article/btob/internet-direct-media-rebrands-widevine-technologies/250332 |title=Internet Direct Media rebrands as Widevine Technologies |date=September 29, 2000 |work=Ad Age |access-date=March 13, 2023}}

In February 2001, Widevine Technologies released Widevine Cypher Enterprise; at the time, techniques such as screen recording and network request monitoring were common. Widevine Cypher used DES-X encryption to prevent these techniques.{{Cite web |url=https://www.streamingmedia.com/Articles/ReadArticle.aspx?ArticleID=63630 |title=Widevine Releases Enterprise Targeted Security Solution |date=February 12, 2001 |last=Kieskowski |first=Ellie |work=Streaming Media |access-date=March 13, 2023}} Widevine Technologies partnered with Bellevue-based streaming company Midstream Technologies in April.{{Cite web |url=https://www.internetnews.com/it-management/midstream-teams-with-widevine/ |title=Midstream Teams with Widevine |date=April 18, 2001 |work=InternetNews |access-date=March 13, 2023}} Baker returned to the company in 2001, leading it through a restructuring process; the process involved recapitalizing the company and firing many of its employees.{{Cite news |url=https://www.seattlepi.com/news/article/16-million-boost-for-Seattle-s-Widevine-1201400.php |title=$16 million boost for Seattle's Widevine |date=April 18, 2006 |last=Cook |first=John |work=Seattle Post-Intelligencer |access-date=March 13, 2023}}

In June 2003, Widevine Technologies secured US$7.8 million in funding from venture capital firms Constellation Ventures and Pacesetter Capital.{{Cite web |url=https://www.bizjournals.com/seattle/stories/2003/06/16/daily12.html |title=Widevine raises $7.8 million |date=June 17, 2003 |work=Puget Sound Business Journal |access-date=March 13, 2023}} That same year, Widevine Technologies partnered with Taiwanese telecommunications company Chunghwa Telecom in an effort to secure their video-on-demand service.{{Cite web |url=https://www.bizjournals.com/seattle/stories/2004/03/08/focus2.html |title=VCs betting on Widevine's data-encryption software |date=March 7, 2004 |last=Meisner |first=Jeff |work=Puget Sound Business Journal |access-date=March 13, 2023}} Widevine Technologies would receive further funding in 2004 from Constellation Ventures and Pacesetter Capital, along with Phoenix Capital Partners, in a funding round led by VantagePoint Venture Partners, netting the company $13 million.{{Cite web |url=https://www.bizjournals.com/seattle/stories/2004/02/09/daily11.html |title=Widevine raises $13 million |date=February 10, 2004 |work=Puget Sound Business Journal |access-date=March 13, 2023}}

Widevine Technologies branched out into digital watermarking in 2005, partnering with content processing company TVN Entertainment (now Vubiquity) for its Mensor system.{{Cite web |url=https://rethinkresearch.biz/articles/widevine-lands-tvn-as-first-customer-for-watermarking/ |title=VCs betting on Widevine's data-encryption software |date=November 16, 2005 |last=White |first=Peter |work=Rethink Technology Research |access-date=March 13, 2023}} Widevine Mensor inserts a 64-bit payload into the signal, a computationally inexpensive operation.{{Cite web |url=https://www.tvtechnology.com/equipment/widevines-mensor |title=Widevine's Mensor |date=August 1, 2007 |last=Rassool |first=Reza |work=TV Technology |access-date=March 13, 2023}}

In April 2006, Constellation Ventures, Pacesetter Capital, Phoenix Capital Partners, and VantagePoint Venture Partners joined digital communications company Cisco Systems and Canadian telecommunications company Telus to invest $16 million into Widevine Technologies. Cisco's involvement in the investment followed its acquisition of set-top box manufacturer Scientific Atlanta for $7 billion.{{Cite web |url=https://www.cnet.com/culture/cisco-backs-drm-start-up/ |title=Cisco backs DRM start-up |date=April 19, 2006 |last=Reardon |first=Marguerite |work=CNET |access-date=March 13, 2023}} In a six-year agreement, Widevine was awarded a contract with Telus to use its technology in Telus's platforms.{{Cite web |url=https://convergedigest.com/telus-selects-widevine/ |title=TELUS Selects Widevine |date=November 12, 2006 |work=Converge Digest |access-date=March 13, 2023}}

On August 3, 2007, Widevine Technologies filed a patent infringement lawsuit against content security company Verimatrix.{{Cite web |url=https://advanced-television.com/2007/08/03/widevine-alleges-patent-breach/ |title=Widevine alleges patent breach |date=August 3, 2007 |work=Advanced Television |access-date=March 13, 2023}} The two companies reached a settlement in March 2010.{{Cite web |url=https://www.nexttv.com/news/widevine-verimatrix-settle-patent-dispute-258469 |title=Widevine, Verimatrix Settle Patent Dispute |date=March 24, 2010 |last=Spangler |first=Todd |work=Multichannel News |access-date=March 13, 2023}}

Vendors utilizing Widevine steadily increased up until 2010. In August 2008, CinemaNow used Widevine to expand its reach to multiple devices, including the Nintendo Wii, disc players from LG and Samsung, and the iPhone and iPod.{{Cite web |url=https://www.latimes.com/archives/blogs/technology-blog/story/2008-08-18/cinemanow-widevine-bring-movies-to-more-devices |title=CinemaNow, Widevine bring movies to more devices |date=August 18, 2008 |last=Healey |first=Jon |work=Los Angeles Times |access-date=March 13, 2023}} To implement DRM into Microsoft Silverlight for browsers not using Microsoft Windows, Microsoft worked with Widevine Technologies.{{Cite web |url=https://www.latimes.com/archives/blogs/bit-player/story/2008-04-14/microsoft-silverlight-and-widevine |title=Microsoft, Silverlight and Widevine |date=April 14, 2008 |work=Los Angeles Times |access-date=March 13, 2023}} Widevine was also implemented into several streaming services using Adobe Flash, including content from Sony and Warner Bros. distributed in the virtual social network Gaia Online.{{Cite web |url=https://mashable.com/archive/widevine-sony-warner-gaia |title=Sony, Warner Virtual World Cinemas Sign Widevine for DRM Protection |date=January 3, 2008 |last=Nicole |first=Kristen |work=Mashable |access-date=March 13, 2023}}

In December 2009, Widevine received an additional $15 million in funding from telecommunications company Liberty Global and Samsung Ventures, the venture capital subsidiary of Samsung.{{Cite web |url=https://www.seattletimes.com/business/widevine-pulls-in-15-million-from-investors/ |title=Widevine pulls in $15 million from investors |date=December 14, 2009 |work=Seattle Times |access-date=March 13, 2023}} Samsung would expand its use of Widevine in June 2010.{{Cite web |url=https://www.nexttv.com/news/samsung-taps-widevine-connected-devices-47571 |title=Samsung Taps Widevine for Connected Devices |date=June 22, 2010 |last=Dickson |first=Glen |work=Broadcasting & Cable |access-date=March 13, 2023}} LoveFilm signed a deal with Widevine in July 2010.{{Cite web |url=https://techcrunch.com/2010/07/29/lovefilm-the-netflix-of-europe-signs-deal-with-widevine-to-beef-up-multi-platform-play/ |title=Lovefilm, the Netflix-of-Europe, signs deal with Widevine to beef up multi-platform play |date=July 29, 2010 |last=O'Hear |first=Steve |work=TechCrunch |access-date=March 13, 2023}}

On December 3, 2010, Google announced that it had acquired Widevine for an undisclosed amount.{{Cite web |url=https://www.latimes.com/archives/blogs/technology-blog/story/2010-12-03/google-buys-anti-piracy-firm-widevine |title=Google buys anti-piracy firm Widevine |date=December 3, 2010 |last=Healey |first=Jon |work=Los Angeles Times |access-date=March 13, 2023}} The acquisition occurred on the same day Viacom filed an appeal in Viacom v. YouTube, a case regarding Google's role in users uploading content owned by Viacom onto YouTube.{{Cite web |url=https://www.engadget.com/2010-12-05-google-spends-a-few-more-million-picks-up-widevine-drm-software.html |title=Google spends a few more million, picks up Widevine DRM software firm |date=December 5, 2010 |last=Murph |first=Darren |work=Engadget |access-date=March 13, 2023}} A CNN report in February 2011 revealed that Google had paid $150 million for Widevine, despite an internal valuation of the company being between $30 million and $40 million, making it the company's ninth largest acquisition until that point.{{Cite web |url=https://money.cnn.com/galleries/2011/technology/1108/gallery.googles_biggest_acquisitions.fortune/2.html |title=Google's 10 biggest acquisitions (so far) |date=August 16, 2011 |last=Konrad |first=Alex |work=CNN |access-date=March 13, 2023}}

Widevine is divided into three security levels. The security level used is dependent on the usage of a trusted execution environment (TEE) in the client device. For example, ARM Cortex-A processors implement TrustZone technology, allowing cryptography and video processing to occur entirely within the TEE.{{Cite web |url=https://www.androidauthority.com/widevine-explained-821935/ |title=What is Widevine digital rights management (DRM) and why does it matter? |date=November 27, 2022 |last=Triggs |first=Robert |work=Android Police |access-date=March 13, 2023}} In Widevine L1, media decryption and processing occurs entirely in a TEE, and content is available in its original resolution. In Widevine L2, media decryption and processing occurs in software or dedicated video hardware, despite the presence of a TEE, and content is available in a fixed resolution. In Widevine L3, media decryption and processing occurs in software and no TEE is present, and content is available in a fixed resolution.{{Cite web |url=https://www.xda-developers.com/check-widevine-drm-status-android/ |title=How to check if your Android device supports Widevine DRM |date=March 27, 2021 |last=Davenport |first=Corbin |work=XDA Developers |access-date=March 13, 2023}}

In Android, Widevine L1 can be implemented into Stagefright, Android's media playback engine.{{Cite web |url=https://source.android.com/docs/core/media |title=Media |publisher=Android Open Source Project |access-date=March 13, 2023}} This is implemented in Qualcomm chips, where an OpenMAX (OMX) component communicates with the video driver at the kernel level. Multimedia memory is carved out through the memory management unit driver for ION, a memory manager introduced in Android 4.0 to address the various memory management interfaces across Android.{{Cite web |url=https://lwn.net/Articles/480055/ |title=The Android ION memory allocator |date=February 8, 2012 |last=Zeng |first=Thomas |publisher=LWN.net |access-date=March 13, 2023}} The input/output buffer is then allocated, and the content is decrypted and stored to a secured input buffer in TrustZone.{{Cite web |url=https://www.penguinsolutions.com/about-us/newsroom/protecting-premium-hd-content-widevine-digital-rights-management-drm-inforce-platforms |title=Protecting your premium HD content with Widevine Digital rights management (DRM) on Inforce platforms |date=September 10, 2016 |work=Penguin Solutions |access-date=March 13, 2023}}

Widevine uses multiple standards and specifications, including MPEG Common Encryption (CENC), Encrypted Media Extensions (EME), Media Source Extensions (MSE), and Dynamic Adaptive Streaming over HTTP (DASH).{{sfn|Google|2017|p=5}} In addition, Widevine supports the HTTP Live Streaming (HLS) protocol, developed by Apple Inc. in 2009.{{sfn|Google|2017|p=9}}

In one implementation of Widevine, a browser receives encrypted content from a content delivery network (CDN). The content is then sent to the Content Decryption Module (CDM), which creates a license request to send to the license server. The player then receives a license from the license server and passes it to the CDM. To decrypt the stream, the CDM sends the media and the license to the OEMCrypto module, required to decrypt the content.{{sfn|Google|2017|pp=10-13}} OEMCrypto is an interface to the TEE; most implementations ensure that session keys, decrypted content keys, and the decrypted content stream are not accessible to other running applications. This is usually accomplished through a secondary processor with separate memory.{{sfn|Google|2013|p=9}} The content is then sent to the video stack and displayed to the end user in chunks.{{sfn|Google|2017|p=11}} License request and license response messages are sent and received using Protocol Buffers.{{sfn|Google|2017|p=10}}

Vendors may implement their own proxy server within the license server, in cases where user authorization is managed by the vendor's preexisting proxy server.{{sfn|Google|2019|p=6}} This setup requires the use of the proxy server as a middleman.{{sfn|Google|2019|p=7}} Widevine requires the use of service certificates beginning in Chrome 59, along with iOS and some configurations of ChromeOS.{{sfn|Google|2019|p=20}}{{refn|group=note|In ChromeOS, service certificates are required when remote_attestation_verified is enabled. remote_attestation_verified requires the use of a Trusted Platform Module (TPM) and is enabled at boot for devices with a TPM.{{sfn|Santos|Gummadi|Rodrigues|2009|p=3}}}} A proxy server may choose to refuse to issue licenses for browsers that do not implement a "verifiable" framework, otherwise known as Verified Media Path (VMP). Notably, browsers running on Linux are not included in VMP.{{Cite web |url=https://arstechnica.com/gadgets/2020/01/cbs-all-access-serves-ads-but-not-content-to-linux-users/ |title=Linux Star Trek fans, rejoice: CBS All Access now works in your OS |date=January 31, 2020 |last=Salter |first=Jim |work=Ars Technica |access-date=March 15, 2023}} Similarly, the High-bandwidth Digital Content Protection (HDCP) version used on the client device may be enforced by the proxy server.{{sfn|Google|2019|p=31}}

In Widevine L1 devices, certificate provisioning is usually performed once. During provisioning, the CDM creates a nonce and derives keys for certificate decryption and integrity checks, as well as dynamically generated buffers. The device key is treated as the Root of Trust (RoT). The RoT-derived client key protects the request using HMAC.{{sfn|Patat|Sabt|Fouque|2022a|p=5}} The RoT is established through a factory-provisioned component called the "keybox". The keybox is 128 bytes long with two special fields. The integrity of the keybox is checked by verifying the last eight bytes match a magic number ("kbox") followed by a cyclic redundancy check (CRC-32).{{sfn|Patat|Sabt|Fouque|2022a|p=6}} The other 120 bytes comprise an internal device ID (32 bytes), an Advanced Encryption Standard key (16 bytes), and a provisioning token (72 bytes).{{sfn|Patat|Sabt|Fouque|2022a|p=7}}

Each content key is associated with a 128-bit key control block, specifying security constraints. The key control block ensures data path security requirements on clients such as Android, where video and audio are encrypted separately, and to provide a timeout value to the TEE. The block is AES-128-CBC encrypted with a random initialization vector (IV), and the fields are defined in big-endian byte order. The values of the block comprise a verification field, a duration field (expressed in seconds), a nonce, and control bits, all 32 bits each.{{sfn|Google|2013|p=16}} The control bits are a series of bit fields controlling the HDCP version that can be used, the data path type, whether or not a nonce should be used, and the Copy General Management System (CGMS) used.{{sfn|Google|2013|p=17}} Despite this, vendors may still choose to encrypt audio and video with the same key or may not even encrypt the audio at all.{{sfn|Patat|Sabt|Fouque|2022b|p=5}}

Widevine is included in most major web browsers, including Google Chrome. Derivatives of Chromium, including Microsoft Edge, Vivaldi,{{Cite web |url=https://www.xda-developers.com/google-is-deprecating-widevine-for-chromium/ |title=Google is deprecating the Widevine CDM for Chrome and Chromium-based browsers |date=October 21, 2022 |last=Conway |first=Adam |work=XDA Developers |access-date=March 15, 2023}} and Opera, also implement Widevine.{{Cite web |url=https://www.bleepingcomputer.com/news/microsoft/chromium-microsoft-edge-can-play-4k-netflix-video-unlike-chrome/ |title=Chromium Microsoft Edge Can Play 4K Netflix Video, Unlike Chrome |date=April 2, 2019 |last=Abrams |first=Lawrence |work=BleepingComputer |access-date=March 15, 2023}} Since June 2016, Firefox has supported Widevine directly in an effort to remove NPAPI support.{{Cite web |url=https://blog.mozilla.org/futurereleases/2016/04/08/mozilla-to-test-widevine-cdm-in-firefox-nightly/ |title=Mozilla To Test Widevine CDM in Firefox Nightly To Facilitate Video Watching Online |date=April 7, 2016 |publisher=Mozilla |access-date=March 13, 2023}} In addition, Widevine is supported on Android and iOS.{{sfn|Google|2017|p=5}} Streaming services utilizing Widevine include Netflix, Disney+,{{sfn|Patat|Sabt|Fouque|2022a|p=1}} Amazon Prime Video, Max, Hulu, Paramount+, and Discovery+.{{Cite web |url=https://developers.google.com/widevine/drm/overview |title=Overview |publisher=Widevine}} Since Android 5, the version of Google Chrome used in Android supports Widevine.{{sfn|Google|2017|p=23}} In February 2021, Firefox for Android added Widevine.{{Cite web |url=https://www.pcmag.com/news/firefox-85-for-android-allows-drm-protected-content-to-play-again |title=Firefox 85 for Android Allows DRM-Protected Content to Play Again |date=February 2, 2021 |last=Humphries |first=Matthew |work=PCMag |access-date=March 13, 2023}}

In Android, Widevine is implemented through a hardware abstraction layer (HAL) module plugin. The Widevine library on Android translates Android DRM API calls to Widevine CDM ones, and its role varies depending on the security level implemented; in Widevine L1, the Widevine library acts as a proxy for the TEE, while in L3, the library contains the obfuscated CDM. Additionally, the library liboemcrypto.so marshals and unmarshals requests to the Widevine trustlet for Widevine L1 through a specialized TEE driver, such as QSEEComAPI.so for Qualcomm Secure Execution Environment (QSEE).{{sfn|Patat|Sabt|Fouque|2022a|p=3}}

iOS does not natively support DASH or CENC. To work around this limitation, Widevine transmuxes DASH to HLS; the Universal DASH Transmuxer (UDT) parses the DASH manifest using an XML parser, such as libxml2. The UDT then creates an HLS playlist.{{sfn|Google|2017|p=24}}

On May 31, 2021, support for 32-bit Linux was stopped, and DRM-protected content cannot be played on this platform.{{cite web | url=https://news.itsfoss.com/netflix-issue-32-bit-linux/ | title=Netflix Not Working on 32-bit Linux? Blame it on Google | date=4 July 2021 }}{{Cite web|url=https://support.mozilla.org/en-US/kb/enable-drm|title=Watch DRM content on Firefox | Firefox Help}}

Widevine has been exploited multiple times. Researchers at Ben-Gurion University of the Negev discovered a vulnerability in Widevine in June 2016; the vulnerability allowed users to obtain a decrypted version of protected content in cache.{{Cite web |url=https://www.theregister.com/2016/06/28/google_widevine_drm/ |title=Google's Widevine DRM doesn't quite manage |date=June 28, 2016 |last=Chirgwin |first=Richard |work=The Register |access-date=March 13, 2023}}

In January 2019, security researcher David Buchanan claimed to have broken Widevine L3 through a differential fault analysis attack in Widevine's white-box implementation of AES-128, allowing Buchanan to retrieve the original key used to encrypt a stream. The MPEG-CENC stream could then be decrypted using ffmpeg.{{Cite web |url=https://www.pcmag.com/news/report-googles-widevine-l3-drm-cracked |title=Report: Google's Widevine L3 DRM Cracked |date=January 3, 2019 |last=Humphries |first=Matthew |work=PCMag |access-date=March 13, 2023}}{{Cite web |url=https://www.androidpolice.com/2019/01/02/googles-widevine-l3-drm-used-by-netflix-hulu-and-hbo-has-been-broken/ |title=Google's Widevine L3 DRM, used by Netflix, Hulu, and HBO, has been broken |date=January 3, 2019 |last=Hager |first=Ryne |work=Android Police |access-date=March 13, 2023}} A similar vulnerability was exploited in October 2020.{{Cite web |url=https://krebsonsecurity.com/2020/10/google-mending-another-crack-in-widevine/ |title=Google Mending Another Crack in Widevine |date=March 13, 2023 |last=Krebs |first=Brian |author-link=Brian Krebs |work=Krebs on Security |access-date=March 13, 2023}}

In 2021, the Android version of Widevine L3 was reverse engineered and broken by security researchers.{{sfn|Patat|Sabt|Fouque|2022a|p=10}} The same year, Qi Zhao presented the first attack breaking Widevine L1 in Android by recovering the L1 keybox.{{cite web |last1=Zhao |first1=Qi |title=Wideshears: Investigating and Breaking Widevine on QTEE |url=https://hyrathon.github.io/posts/wideshears/wideshears-wp.pdf |website=Hyrathon's Blog |access-date=26 July 2023}}

In 2019, a developer tried to bundle Widevine in an Electron/Chromium-based application for video playing and did not get any response from Google after asking for a license agreement, effectively blocking DRM usage in the project.{{Cite web|url=https://boingboing.net/2019/04/03/i-hate-being-right-2.html|title=After years of insisting that DRM in HTML wouldn't block open source implementations, Google says it won't support open source implementations|last=Doctorow|first=Cory|website=Boing Boing|date=3 April 2019|language=en-US|access-date=2019-07-25|archive-date=2022-09-04|archive-url=https://web.archive.org/web/20220904051554/https://boingboing.net/2019/04/03/i-hate-being-right-2.html|url-status=live}}{{cite web |last1=Maddock |first1=Samuel |date=2019-04-02 |title=I tried creating a web browser, and Google blocked me |url=https://blog.samuelmaddock.com/posts/google-widevine-blocked-my-browser/ |website=Samuel Maddock’s Blog |access-date=14 May 2021 |archive-date=2021-05-24 |archive-url=https://web.archive.org/web/20210524070441/https://blog.samuelmaddock.com/posts/google-widevine-blocked-my-browser/ |url-status=live }} He later got the reply:

{{Quote|text=I'm sorry but we're not supporting an open source solution like this{{sic}}|sign=Google Widevine Support|source=https://blog.samuelmaddock.com/widevine/gmail-thread.html}}

The same happened to other Electron projects.{{Cite web|url=https://github.com/electron/electron/issues/12427|title=Netflix isn't working even with Widevine correctly loaded. · Issue #12427 · electron/electron|website=GitHub|language=en|access-date=2019-07-25|archive-date=2019-09-09|archive-url=https://web.archive.org/web/20190909065942/https://github.com/electron/electron/issues/12427|url-status=live}}

Widevine does support Electron and Electron projects through a third-party integrator.{{Cite web |last=P |first=Bryce |title=Electron Open Source Stream Downloader |url=https://castlabs.com/resources/downstream/ |access-date=2024-11-06 |website=castLabs}}

• FairPlay
• Marlin
• PlayReady

{{Reflist|group=note}}

{{Reflist}}

• {{Cite book |author=((Google)) |date=April 3, 2019 |title=Widevine DRM Proxy Integration}}
• {{Cite book |author=((Google)) |date=March 6, 2017 |title=Widevine DRM Architecture Overview}}
• {{Cite book |author=((Google)) |date=February 25, 2013 |title=WV Modular DRM Security Integration Guide for Common Encryption (CENC)}}
• {{Cite conference |url=https://ieeexplore.ieee.org/document/9833867 |title=Exploring Widevine for Fun and Profit |last1=Patat |first1=Gwendal |last2=Sabt |first2=Mohamed |last3=Fouque |first3=Pierre-Alain |date=2022a |publisher=IEEE}}
• {{Cite conference |url=https://ieeexplore.ieee.org/document/9833728 |title=WideLeak: How Over-the-Top Platforms Fail in Android |last1=Patat |first1=Gwendal |last2=Sabt |first2=Mohamed |last3=Fouque |first3=Pierre-Alain |date=2022b |publisher=IEEE}}
• {{Cite conference |url=https://dl.acm.org/doi/10.5555/1855533.1855536 |title=Towards trusted cloud computing |last1=Santos |first1=Nuno |last2=Gummadi |first2=Krishna |last3=Rodrigues |first3=Rodrigo |date=June 15, 2009 |publisher=Association for Computing Machinery}}

{{Google LLC}}

Category:Digital rights management systems

Category:Google software

Category:2010 mergers and acquisitions