At that moment, I did not think about the page with the exploit, and instead of carefully analyzing the file and figuring out what the problem was, I simply deleted it. The only thing I thought about when I saw the unusual behavior of the system is that someone is promoting their site in a rather original way. Several years have passed, but since then I have not seen such cases. After reading the article about the video virus, I decided that at least this time I shouldn't miss the opportunity to find out how safe some of the most harmless and widespread files in the world are.
Video File
And since the dear TipTop left a comment, indicating the link to the file, I did not waste time and quickly downloaded the torrent file. But I was not alone - at the same time with me, the same video file was downloaded by about 15 more people who, I thought, also want to analyze it. But now I realized that most of them most likely had other intentions and did not know that there would be no kinetic today.After the download was completed, knowing that other players could not play this file, I immediately opened it in Windows Media Player, and the first thing I saw was the message: “Download media usage rights”:
After that, a more convincing message appeared, suggesting to download the License-Installer file, which, by the way, had already been checked by the antivirus and turned out to be 100% clean:
After carefully reviewing the message, I pressed the "Download Now" button and, while waiting for any reaction from the antivirus, saw a familiar window offering to download a file from the server. license.compress.to:
And then the first question arose, if the server is indicated on the first window free-license.imgpop.com, then why this wonderful file, offers to download the license from the server license.compress.to? To find out what the problem is, I visited both sites, hoping to find something tasty there, but as expected, I did not find anything there.
DRM protection
After that, the first thing that came to mind was "launch a sniffer", but refrained (and did the right thing) - deciding to open the file in a Hex editor. I opened a file in the Hex editor, which weighed 150 MB and, fortunately, everything was very simple, because already on the 20th line I found this piece of text:It has become much more interesting. Opened the page httr: //free-license.imgpop.com/venuf.php? id = Movie_0001.wmv which redirected (HTTP / 1.1 302) to the page: httr: //free-license.imgpop.com/venuf/index.htm, and there I saw a familiar picture, just a little more, and even in the browser:
While everything was going well and wanting to experiment a little, I decided to change the link from the video file to my own. But, seeing that after changing the line, even WMP could not open the file and, not knowing what to do, asked Google "but, can he tell you what this line is, WRMHEADER version = "2.0.0.0" which (among many others) found with a Hex editor?
The answer was short and clear as daylight - I am dealing with DRM protection of video files. That is, he discovered how, using legal and rather convincing methods, attackers can successfully and confidently distribute malicious files, since: firstly, no antivirus detects that a video file is infected, and secondly, most users trust Microsoft and will definitely run such files.
Moreover, WMP is not the only player that can open DRM protected files. I did not find a complete list of players, but I can say with confidence that Nero ShowTime supports DRM, only, unlike WMP, it reacts more cautiously ... only if you confirm the download of the license, the web page opens in IE (despite the fact that it is not a browser default).
Now comes the fun part: if you change the file extension from .wmv v .asf or in .wma, nothing will change, that is, the players will still play the media file, and what is most dangerous, in most cases .wma files will be opened in Windows Media Player. By the way, I forgot to say, after I opened the video file in the Hex editor, for convenience, I deleted unnecessary bytes and, as a result, the file size became 5.31KB.
Internet Explorer
Probably many people think that “There is no danger in this! I will not download any licenses! Anyway, what does Internet Explorer, WMP and video files have to do with it? " At first I thought so too, because there is a "Cancel" button, but as it turned out, the danger is not small, and "Cancel" will not save anyone if the file is opened in WMP. And Internet Explorer is a browser, software for browsing websites ...I found information that it is possible to hack DRM protection, but I didn’t do it. Firstly, I didn’t know whether it would be possible to change the link, and secondly, I chose an easier way. In file hosts added the line:
127.0.0.1 free-license.imgpop.com
In the root of the local server created a file venuf.php and using WMP I opened a video clip - after a few seconds the following message appeared:
Further, with the help alert (), I decided to try if it supports JavaScript - as a result, I got a blank page. Thought that it really didn’t work, but having connected my intuition, I quickly changed the function alert () on the document.write ()... The result brought a smile: this time the page was not empty, which means Windows Media Player supports JavaScript.
Now, the thought that a media player can open web pages, and even supports JavaScript, haunted me. Wanting to know what this extraordinary player is, he added in the file venuf.php line:
echo $ _SERVER ["HTTP_USER_AGENT"];
and even though I have MSIE 8.0 installed, I got the following message:
Finally, I decided to test one exploit for MSIE, written in JavaScript that causes a denial of service in the browser. I added an exploit to the page, opened the video file and before I could blink, Windows says that "Windows Media Player has stopped working":
As you understand, when trying to play a video file, WMP was forced to disconnect, which means that it is vulnerable to an exploit designed for MSIE. I only tested one exploit, but it was enough to change my ideas about media file security.
Instead of a postscript
After writing the last lines of this article, suddenly one idea came to me: download, install and test one of the most popular multimedia players - Winamp... Which is what I did ... And when I tried to play the file, the following message appeared:
I was almost sure that everything would be the same as with Nero ShowTime, but curiosity made me click on the "Yes" button ... Instead of launching IE, I saw the following:
I didn't immediately understand what the problem was, thinking that anything could happen, but after a few seconds, I remembered what was in the file venuf.php the exploit code for MSIE remains. Further, using the variable $ HTTP_USER_AGENT found out that as well as WMP for its own purposes Winamp uses MSIE 7 Internet Explorer:
True, unlike Windows Media Player, Winamp does not warn where the license file will be downloaded from, but it allows you to use a right click and see the source code of the page ... and also alerts are triggered for it:
Conclusion
At first glance, not everything is as scary as it seems, but I want to draw your attention to the fact that by opening such a file, the user will not be able to stop the exploit from running, and the antivirus program is not able to help, because if this is a new exploit, then, most likely, it has not yet been added to the anti-virus database.Just remember that not all users have other audio and video players installed. And yet, I do not believe that a user who waited 2 hours (at best) to download the long-awaited file, seeing that it is not playing, will just delete it, and no “do not open files in this player!” Will not help ...
UPD:
Protection
To significantly reduce the risk of potential attacks, I recommend disabling automatic license acquisition for DRM-protected files in WMP. To do this, open Parameters(Options) and in the tab Confidentiality(Privacy) uncheck the box " Obtain licenses automatically for protected content"(Download usage right automatically when I play or sync a file):Digital Rights Management (DRM) license is a tool that allows the copyright holder to control access, prevent illegal copying and distribution of their software. Cracking a digital code for most people will not be a feasible task. Therefore, many users quite logically have a question: how can you reset the DRM licenses of Android and what is it?
DRM stands for Digital Rights Management, which means digital rights management. It is realized through the introduction of various technical means by the developer into the software, which do not allow it to be illegally disposed of. As a result, the person who downloaded the product can only use it for their own personal purposes, without the possibility of copying and transferring to other users. The DRM license is a digital lock, the required key to which is at the developer, who is also the copyright holder of this software.
When creating such a digital code, various mathematical algorithms are used, called cryptoalgorithms. We will not go into details and explain what a cryptoalgorithm is, but just note that it is very difficult to crack a DRM license. The most common implementation scheme for this technology on Android is as follows:
- The user buys a phone or tablet, on which, in addition to the OS itself, there is special software from the developer.
- After the device is turned on and activated, the preinstalled software starts its work in a demo version (for a period of a week, a month, etc.). After the trial period expires, the program stops working, offering to buy a paid version from the copyright holder.
The purchase of a premium product is the purchase of a DRM license for the selected application. In addition to the above diagram, there may be other examples of copyright protection implementation on Android devices.
You can learn what a DRM license for Android is by watching the video below.
Reset DRM licenses
Depending on which product is licensed, it is necessary to use one or another solution to the problem. For example, using various hacking software, you can reset the application enable counter. Some utilities allow you to remove the binding of certain files to the site, turn off the need to verify the digital key, and much more.
For your mobile phone running Android OS, you can reset the DRM license without using hacker programs. To do this, it is enough to do the following:
- Go to the main menu of smartphone settings, through the pull-out shutter or from the main screen.
- Select the "Restore and Reset" tab. On Android 5 and up, it is located under the accounts tab.
- Click on the line "Reset DRM (DRMreset)".
You should use this feature very carefully, especially if you do not know what will happen when you reset your DRM license. The fact is that after the actions taken, the user may lose access to certain capabilities and functions of applications already installed in the memory. Also, some proprietary preinstalled programs that are present in phones from Samsung and Sony may simply stop working. But otherwise, the functionality and personalization of the phone will not be affected in any way. A regular factory reset, which can be found in the Restore and Reset tab, will not remove the DRM licenses.
How to remove DRM protection
Recently, many Android software developers have been constantly faced with user protests regarding the inconvenience of a digital license. However, in many products, including mobile applications, multimedia files, etc., it is still used today. Let's consider the main methods that allow you to remove the Digital Rights Management "digital lock" from the most common file types:
- Using specialized utilities. For example, the free programs "DRM Media Converter" or "DRM Removal" can bypass and deactivate DRM protection from many popular file types. These include documents with extensions: .WMV, .M4B, .M4V, .ASF and many others.
- Convert files protected by a digital license using converters. These programs include: Digital Music Converter, Sound Taxi, Note Burner, as well as many others that can be found on the Internet. Despite the fact that they apply only to a narrow range of extensions, after conversion you will get a completely "clean file".
- Using CD and DWD disks. Files with the WMV and WMA extension can be easily and easily removed from digital protection if you have a computer and a blank disc at hand. It is enough to burn WMA to CD, and WMV to DVD, and then copy them back to your PC. After that, the DRM license will be removed from them.
DRM Removal Utility Interface
Note that in many cases, you can find a free alternative to DRM-protected software to use. Also, by buying a paid version of the product from the developers, you guarantee yourself the opportunity to use all the functions and capabilities of the software.
The topic of DRM (Digital Rights Management) continues to be quite distant from Russian realities. A few semi-legal domestic online stores sell their content without any protection.
One of the few Russian online stores that practiceDRM, AllOfMP3, works mainly for export
However, the prospects for the country's accession to the WTO, which have been talked about so much over the past year, forced the state to pay attention, albeit mainly in words, to the problem of copyright protection for digital products. Therefore, it makes sense to familiarize yourself with these questions in more detail.
This topic is very broad and touches on many both moral and legal issues. In this material, we strive to consider it exclusively in the application to portable digital audio players.
The need to protect content from abuse has been evident since the analog era. However, it was only with the advent of digital formats that made it possible to create an exact copy of the original material in the mass availability that this problem took on its current acuteness.
Anti-piracy campaigning in the analog and digital era. Left - a poster from the 80s of the associationBPI(British Phonographic Industry) against home copying of music onto cassette tapes. Right - modern work of the English RARIO7 directed againstP2 P-networks
Major record companies (record labels) and film studios have had a firm grip on virtually the entire audio and video market for decades. For a musician, composer, actor, director, there was only one way to reach a mass audience or viewer, and this path lay through the signing of a contract with one of the largest companies in the relevant field.
Major record companies (top): Warner Music Group, EMI, Sony BMG, Universal Music Group; major film studios (below): 20th Century-Fox, Metro-Goldwyn-Mayer, Paramount, Warner Bros, Universal Studios,SonyPictures
Since the number of candidates for "stars" of music or cinema has always been very, very large, record companies and film studios had the opportunity to dictate their terms. As a result, the lion's share of the profits settled in their pockets. This situation, naturally, more than suited these companies, and the performers, in general, did not remain offended. Consumers simply had no choice.
These numbers show why the record companies were reluctant to change anything.
The situation began to change dramatically in the second half of the 90s, when a fundamentally new method of content delivery - the Internet - began to gain mass distribution. Being uncontrolled by commercial organizations, it potentially gave the inhabitants of the entire globe complete freedom to exchange any data.
The only limitation at that time was the low channel capacity. Audio and especially video in digital form were too large for transmission over the Internet to be practical. This problem was quickly resolved with new lossy compression technologies that provide high quality with acceptable file sizes. In 1995, the MP3 format was introduced, quickly becoming the # 1 format for exchanging music over the Internet. In the following years, the MPEG4 format and its variants, DIVX and XVID, appeared, which solved this problem for video.
Popular "free" formats on the Internet
The dissemination of the Internet and its use for the exchange of compressed digital music and video went “from below”, by the efforts of ordinary users and their non-profit associations-communities. This turned out to be a very unpleasant surprise for record companies and film studios: albeit belatedly, they saw on the Internet a potential replacement for the music and video distribution system they controlled. Banning the Internet in general, or at least the transmission of audio and video content through it, was clearly impossible, although such conversations also took place. In the absence of the ability to plug a new competing channel for delivering music and video to the consumer, content providers have focused their efforts on taking control of it.
Record companies display graphs eloquently indicative of the decline of the traditional media market
The goal of the recording industry and film studios was to transform the Internet into the same content distribution channel under their control, which is the distribution of music and video on media. But in order to achieve this, major changes had to be made in the existing technologies for working with data. The various technologies and techniques that content providers have been using for nearly eight years to achieve this goal can be called "DRM".
What does the industry think the distribution of digital content over the Internet should look like? Ideally, record companies and film studios would like to see a picture like this:
- Digital content must have the same limitations as physical media. That is, it should not be possible to copy it while keeping the original.
- All content should be categorized as "clean" and "unclean". Players should only play "clean", i.e. Content created and legally acquired by content provider companies.
Historically, the computer and Internet space is technically completely unsuitable for such stringent constraints. When laying the foundations for the architecture of modern PCs and the Internet, little thought was given to copyright protection. As a result, most of the standards and protocols that became widespread allowed information to be stored and copied without any restrictions. Recording companies and film studios needed the help of both the computer and consumer electronics industries to accomplish such a technically challenging task as introducing stringent constraints into the existing incredibly extensive infrastructure. At first glance, it may not be clear what could force companies producing software, audio and video equipment to impose such serious restrictions on their consumers. However, content providers have leverage: the stick in the form of the threat of lawsuits and the carrot in the form of sharing the profits from the sale of music and video. The latter proved to be more effective.
Do not think that the consumer is completely alone and defenseless in the face of such a coalition. The greed of content providers in most countries is limited by the so-called "Fair Use" clause of legally purchased audio and video products. In principle, this concept is part of US law, but since the US is the largest market for both content and consumer electronics, Fair Use is considered a global industry. Under these provisions, the purchaser has the full right to make copies of his music and films for his personal use.
In 1984, it was the provision onFairUsewas used in court to legalize home videos (caseUniversalStudiosagainstSony, also known as "businessBetamax»)
Thus, it is impossible to completely deprive the user of the ability to copy content. The Fair Use Statement is a constant headache for all DRM scheme creators. to create a universal mechanism that can distinguish "fair" copying from "dishonest" is impossible in principle. Limits on the number of copies are generally used, although the legality of these limits has been questioned.
The second consequence of the Fair Use clause is the legal purity of audio and video files obtained by copying content from legally purchased media - CD or DVD - to a computer. This puts an end to the industry's attempts to outlaw all DRM-free content.
Thus, the industry has to put up with the existing reality: the user has the right to own and play unprotected DRM files, can copy them freely. At the same time, the developers of DRM technologies are between two fires: on the one hand, the appetites of record companies, film studios and the manufacturers of software, computers and electronics that have joined them, on the other hand, the rights of users protected by law. It is not surprising that so far not a single DRM system has been created that has not received tons of criticism from all sides.
Residents of the United States should be aware of another law, the Digital Millennium Copyright Act. This act protects the right of producers to protect their content and pursues attempts to hack such protection. Therefore, it is considered “fair use” in the United States to copy an audio CD that does not have any protection to a computer, and it is a crime to copy a DVD that has such protection. Fortunately, such laws have not yet become widespread in the world.
DMCAsomewhat weakened the protection of the rights of Americans, which was provided by the provision ofFairUse
Why are DRM issues so tightly linked to portable digital players? The answer is simple: it was in them that compressed digital formats were in demand in the first place. While on stationary equipment the consumer continues to listen to good old CDs without annoying the industry, in the portable field he decisively chooses flash memory and hard drives, coupled with the MP3 format. It was the appearance of the first MP3-players that turned the issue into a serious channel: compressed digital content from the computers of small geeks and nerds came to mass consumer electronics.
The appearance in late 1998 of the Diamond Rio PMP300 MP3 player was marked by two facts. The first is the resounding success of the device and huge sales during the Christmas season. The second is the defeat of the American Recording Association in court - the US judicial system has refused to outlaw MP3 players and the MP3 format.
Gift wrapRioPMP300 in the 1998 Christmas season
It became clear that it was impossible to drive the gin back into the bottle. From that moment, serious work began on creating effective DRM mechanisms, which continues to this day.
Modern DRM concept
In general, the concept of modern DRM schemes is as follows. The goal of DRM is to prevent illegal copying of copyrighted content, while not limiting its “fair use” as much as possible. The architecture of modern PCs is such that any limitation of the actual process of copying information is impossible.
Therefore, the only way to combat illegal copying is to restrict the ability to reproduce the illegally copied content. This is what is the basis of modern DRM - make it impossible to reproduce protected content on all "illegal", that is, unauthorized devices that do not belong to the content owner, be they players or computers.
To achieve this goal, two types of technologies are used - watermarking and coding.
The essence of the watermark technology is to introduce into the content - a digital audio file - certain changes that would not affect its sound in any way, but could be detected by both computer programs and playing devices. Having found a watermark, the reproducing device must make sure that this file is "clean", for example, whether any license for it is stored in the database. Watermarks proved to be quite unreliable, in addition, they required replacing the entire fleet of playing equipment and software with samples supporting this technology, which was a utopia.
Digital watermarks have found their main application in the protection of digital images (an example of the application of technology from the site www.sagesecure.com)
Encoding technology has proven to be more viable, and most modern DRM schemes use it. It involves encrypting all content with a fairly powerful cipher. When the encrypted content is sold, it is sent to the buyer along with the key required for decoding.
The developers of DRM schemes go to various tricks so that the villain-buyer does not start distributing the purchased content along with the key. They try to hide the very existence of the key from him in general, transmitting it secretly, storing it on the computer in a hidden form.
There are two ways to deliver the key to the consumer: together with the content or separately. Separate delivery is considered more reliable, but requires a more complex infrastructure, a separate system for storing keys and transferring them to the user upon an authorized request.
Modern DRM schemes, as a rule, encrypt the key too, binding it individually to each computer, so that from another PC it would be impossible to open the file or write it to the player. This goes against the Fair Use concept, as a user can have multiple computers and laptops. Therefore, DRM schemes usually allow limited copying, either a certain number of times, or on a certain number of computers. Although Fair Use does not stipulate a maximum number of copies for personal use, lawmakers are turning a blind eye to such restrictions.
The desire to restrict the user in his ability to use content has led to the emergence of the concept of "rights" of the user. This is a vendor-defined set of rules and restrictions on the use of content. Actually, it is to this concept that DRM owes its name: Digital Rights Management - management of rights to digital content. The very essence of DRM is that each computer file containing an author's work - music, video, text, computer code - corresponds to the user rights defined by the creator or owner: what he can and cannot do with it. An example of using this scheme is Subscription. The subscription provides monthly payments to the content provider in exchange for unlimited downloads of content from their catalog. In this case, the "rights" of the user include a limit on the lifetime of the content - one month - and are updated monthly when the payment is made. It is worth skipping the payment - the content self-destructs.
There are two stages in the history of DRM. The first of these, from 1998 to 2001, was initiated by record companies concerned with the uncontrolled distribution of music over the Internet. In the course of it, these companies, together with leading players in the electronics industry and consumer electronics, tried to create mechanisms to restrict free copying of content. This stage ended in nothing.
The second stage began in 2003 and continues to this day. It was marked by the fact that leading IT companies drew conclusions from the first stage and took the development into their own hands. As a result, several viable DRM schemes have been created, which are widely used today.
SDMI
During the heyday of this organization, its members were up to two hundred companies, including associations of producers of audio content, the largest recording companies, software manufacturers, developers of hardware solutions, manufacturers of consumer electronics. They all came together at the end of 1998 to "save" music from being copied out of control. Their goal was to develop such technologies for the distribution of digital content, which ensured reliable protection of copyright holders.
This logo was supposed to mark certifiedSDMIdevices
The key technology SDMI relied on was watermarking. "Watermarks" were supposed to be of two types: persistent and unstable. Persistent watermarks had to be preserved even during serious file transformations: compression, transcoding from digital to analog and vice versa, adding noise. The structure of unstable signs was violated during such transformations. Persistent watermarks were used to indicate that the file was protected by SDMI technology, non-persistent - that it had not been modified or transformed by the user in any way. By watermarks, end devices were supposed to distinguish protected SDMI files from unprotected ones, as well as distorted SDMI files from non-distorted ones.
As you can see, the company in SDMI was quite motley, and the interests of its members did not coincide in many ways. Therefore, the standards and specifications developed by the organization were children of compromise. The electronics giants did not want to make players that could not play the already common audio formats. Therefore, the creators of SDMI DRM faced a daunting task of introducing a protection mechanism into the existing model of using unprotected audio files. It was assumed that users would smoothly transition to SDMI content, as there would simply be no other being produced.
The SDMI implementation process was divided into two phases. In the beginning, certified players had to play everything. At the second stage, it was planned to start blocking "illegal" content. No final consensus has been reached on what constitutes “illegal” content.
MusicDish Survey of Industry Experts
The SDMI concept generally had many weaknesses. The main goal of the standards was to protect CDs from copying content from them with subsequent illegal distribution. The project participants had no idea what to do with the millions of unprotected MP3 files already existing on the Internet. Not supporting them meant losing the market for electronics manufacturers. And to support is to indulge in piracy, the record companies did not agree with this. This caused a split in the already not very slender ranks of the association.
In addition, the use of watermarks has proven to be ineffective as a method of protection. In 2000, the association published an open letter urging anyone to hack into their watermark-based security system. Those who answered the challenge took part in a competition in which they were tasked with removing watermarks from a protected SDMI audio file within a limited time. The result was discouraging for SDMI: watermarks were successfully removed, moreover, it was demonstrated that watermarking technology of any complexity will inevitably be hacked in the context of its actual commercial use.
Scheme of a task for participants in the SDMI competition to hack its technology (from the materials of the Princeton team)
This failure exacerbated the controversy among the SDMI contributors. Compromises between record companies and software and hardware vendors were increasingly difficult. As a result, three years of work ended in nothing, the second stage of SDMI implementation did not come. The participants parted unhappy with each other.
From that point on, record companies finally let go of the online content market. Unable to make concessions to the computer industry during the time of SDMI's work, they were put out of the game: without the help of IT corporations and their technologies, they were unable to create and implement any DRM scheme.
IT companies, by contrast, learned from SDMI's bad experience and got down to business on their own. They will create future DRM schemes exclusively for their own needs and will achieve much greater success in this.
There are few reminders left today about SDMI and its development. Sony's DRM, Open MagicGate, is based on SDMI specifications. SD memory cards (Secure Digital Cards) are a living monument of the organization. Back in 1999, Matsushita, Toshiba and Sandisk did not see the future for the new memory card format apart from SDMI.
Modern memory cards remember the deceasedSDMI: abbreviationSecureDigital, technologyMagicGatefromSonydesigned according to specificationsSDMI
SDMI's activities did have one important consequence, although not the one that the organization's members hoped for. During its activity, the world's main manufacturers of consumer electronics - Sony, Panasonic, Philips, Toshiba, Casio, JVC, Pioneer, Sharp - either refrained from promoting digital audio players until the final approval of the specifications, or released products with SDMI-restrictions, which were significantly more expensive than their counterparts. and less comfortable. As a result, it is in many ways the long and fruitless activity of SDMI that is to blame for the loss of the market by traditional manufacturers and the rise of new companies such as Apple, iRiver, Mpio.
2000 - high price, the use of then expensive and limited capacitySD- andMMC-cards and useSDMI-technologies interfere with devices from leading manufacturers (TDK, Panasonic, Aiwa, SonyandPhilips) keep the market
After the SDMI activity dwindled, the DRM market went through a period of stagnation for a couple of years. However, for a number of companies, these years have been a time of intense work. The years 2003-2004 revealed to the world two new DRM schemes, which are now leading the battle for the global market for legal content: FairPlay from Apple Computers and PlaysForSure from Microsoft.
Latest news on the sitesdmi. org, December 2006
FairPlay
In 2000, while SDMI's digital watermarking scheme was undergoing a massive flop, a small company, Veridisc, was working on a DRM scheme that would have the largest market share for legal online sales 5 years later. Called FairPlay, this technology was licensed in 2001 by Apple Computers to become the cornerstone of its online digital music store iTunes in 2003.
Developer logoFairPlay
Apple was wise to take a break and enter the market with its offering when most of the US population was already connected to the Internet. A significant part of them did not have the ability or desire to download music via P2P networks, and they became the first clients of the new service.
Unlike SDMI, FairPlay does not use a digital watermarking method, but an encoding method. Its work involves:
- ITunes Server
- AAC audio content encoded using FairPlay algorithms
- ITunes software installed on the buyer's PC
- IPod player
When a track is purchased by a user in the iTunes online store, the server encodes it using the Master Key. This key is then in turn encoded with a key called the User key. The MP4 container that the user receives contains the encoded audio stream and the encoded master key. Separately, after confirming the transaction, the user's key is sent. The user key is individual for each track.
iTunes stores all user keys in a special database. The database, in turn, is encoded with another key, called the System key, which is individual for each computer. In Windows OS, in particular, the System key is generated using the BIOS version, Windows version and processor name. A second copy of the user's key database is stored on the iTunes server in the user's account. The system keys are also stored there.
General scheme of workFairPlay
This system allows you to realize all the features and limitations of FairPlay DRM. When playing a protected file from a computer, iTunes decodes the corresponding User key using the individual System key of the PC. Accordingly, iTunes installed on a "foreign" machine will not be able to play this file, because does not have the correct User key. The iTunes server allows you to create no more than five System keys per iTunes account, if this number is exceeded, it simply will not give the user key database to the new machine. This allows the user to use a maximum of five computers to listen to and record protected music on the iPod.
When copying files to iPod, iTunes transfers the MP4 container and the decoded user key to the player. Thus, files can also be transferred to iPod only using an authorized version of iTunes that has the appropriate System key. During playback, the player decodes the Master key using the User key, and decodes the audio stream using the Master key.
Such a three-step system deprives the user of direct access to the decoding master key, and also binds this key to a specific computer, which, in fact, is the main task of DRM.
FairPlay is by no means some kind of extremely successful and effective DRM system, at the very least it copes with its tasks and nothing more. Apple has achieved success in spite of rather than due to FairPlay. However, it should be stated that this DRM scheme is quite invisible to the user and does not cause him a hassle, at least as long as he remains within the iTunes Store - iTunes - iPod scheme.
The fact that FairPlay is one of the levers used by Apple to retain its users has been criticized for a very long time. Tracks purchased from the iTunes online store cannot be played using any player other than an iPod, so the longer a person owns an iPod and, accordingly, the more music he buys from iTunes, the more difficult it will be for him. switch to players from another manufacturer, because this will mean the loss of the entire music collection.
In turn, iPods do not support any DRM, except for FairPlay, which restricts users of Apple players from choosing online stores exclusively from iTunes.
This highly closed system raises many complaints from various quarters. The case comes to lawsuits from entire countries, mostly European, where the share of iPods is small enough for the owners of these players to think about buying a device from another manufacturer, and large enough for the voice of these owners to be heard. Apple Computer reacts to this in a "no-to-judge" style — with the largest market share and a near-monopoly position in the US, it can afford to say it doesn't need to keep its users by force.
Satirical poster on the topicFairPlay
Windows Media DRM for Portable Devices (Janus)
Unlike Apple, Microsoft was a contributor to SDMI. This fact reflects the difference in the approaches of companies in the development of DRM. Apple needed the most rigid, closed system possible solely for use in its vertically integrated iTunes Store-iTunes-iPod scheme. Microsoft was striving to create what SDMI had failed to do — a universal industry standard for DRM.
Hence the different requirements for the concept. Apple had a clear uniform set of rights and restrictions for the user, for example, no more than five computers with iTunes installed per iTunes account. The DRM scheme had to ensure that only these requirements were met; it did not need to be either flexible or universal.
Microsoft was trying to create a system that could then be used by hundreds, if not thousands, of companies around the world: Internet services, playback device manufacturers. Each of these companies has its own views on the rights and restrictions for customers. This required maximum flexibility, versatility, and customization from the DRM scheme.
It's no secret that most iPod owners today are Windows users. For Apple, this OS is "hostile territory", the company's ability to develop software for it is limited. Microsoft, on the other hand, can literally do whatever it wants here.
As a result, Microsoft's DRM is not a humble coding system, but a rather extensive set of technologies and standards, collectively called PlaysForSure (P4S). PlaysForSure is the name of the certification program, the DRM scheme itself is called Windows Media DRM for Portable Devices (Windows Media DRM for portable devices) or by its codename, Janus DRM.
These logos are used to mark devices certifiedPlaysForSure
Its key components are:
Online services digital music sales certified according to P4S standards.
Audio formatWMA(Windows Media Audio for video - WMV, Windows Media Video). The format is proprietary to Microsoft. All content in the PlaysForSure system must be compressed in this format. Unprotected WMA and WMV files also exist outside the P4S system. Within this system, they are encrypted, the encryption key is stored separately from the content. The latest version of the coding system is codenamed Janus. WMA and WMV files with P4S DRM are usually containers that, in addition to the content, store information about the location of the license.
FormatWMAbelongs to the family of formatsWindowsMediaowned byMicrosoft
License... This tool is the fundamental difference between P4S and Fairplay. A P4S license is a collection of data associated with a specific piece of content, such as a song or a movie. It includes the key required to decode the content, as well as the rules and restrictions for the buyer. Rules and restrictions can be very diverse, from the most liberal (do whatever you want with the file) to the most stringent (for example, you can view the file once only on this computer, after which it will self-destruct). The rules are set by the content seller. This flexible approach makes PlaysForSure convenient for online service owners to practice a wide variety of business models.
General scheme of workJanus DRM
License center... In Janus DRM licenses are not included in the content container, but are supplied separately. For this purpose, there are special online licensing centers called License Clearing House. All licenses are stored in these centers and are sent to the user upon request of the next P4S component, the Windows Media Player PC software.
Windows Media Player is analogous to iTunes for P4S DRM. This software is used to record content on P4S certified portable digital players. Also WMP keeps a database of licenses. When an attempt is made to play a protected file or write it to a portable device, the program searches the database for the corresponding license. If there is none, it tries to find a link to the License Clearing House inside the file and download the license from there. If it succeeds, the program executes the user's command, otherwise it will receive an error message. As with PlaysForSure, each installed copy of WMP has its own unique code, which is used to restrict the ability to play content on other computers.
WindowWindows Media Player 11
MTP(Media Transfer Protocol). This is another significant difference between PlaysForSure and FairPlay. The latter uses the usual UMS (MSC) protocol to transfer data to the player. Microsoft's UMS seemed "insufficiently secure", which prompted it to develop a new protocol.
In fact, it is an evolution of the Picture Transfer Protocol (PTP), developed in 2000 by I3A (International Imaging Industry Association) for exchanging data with digital cameras.
TargetMicrosoft- create a convenient replacement for manufacturersMSCfor players, which in digital photography has becomePTP
The difference between MTP and UMS is the ability to work with closed file systems, which is convenient for many player manufacturers. The fact is that many companies, especially those operating in the American market, are afraid to make their players UMS-compatible with the FAT file system, in order to avoid claims from the recording associations. Instead, closed file systems are selected. Before the advent of MTP, this necessitated the use of the same proprietary protocols and, as a result, the installation of special drivers and software on the computer. MTP made it possible to somewhat universalize this process - now all such players can interact with a PC through it.
MTPbrought together a variety of manufacturers who were previously forced to use proprietary proprietary protocols orMSC
A significant drawback of MTP is its compatibility exclusively with Windows XP with installed Windows Media Player at least version 10 and the need to use exclusively WMP to record content on the player. In addition, there are still a few third-party devices that support the connection of MP3 players as storage devices - car radios, stereos, etc. - incompatible with the new MTP.
While car radios withUSB-Connectors are becoming more commonplace on the roads, inability to use with themMTP-players is an increasing concern
Microsoft is aware of these shortcomings of MTP versus UMS and is working hard to improve the protocol. In particular, the latest versions of it support the transfer and storage of all types of files on the player and are visible in the "My Computer" window, which allows you to use the player as a removable storage device. This, of course, does not apply to music, you still have to use WMP for it, otherwise the player will simply not see the recorded files. Also, the PlayFromDevice specification has been developed, certified third-party devices will be able to support the connection of MTP players. So far, an example of such devices is the Xbox 360 game console, of course, from Microsoft.
ConnectivityMTPdevices are positioned as one of the advantagesXbox
Despite its best efforts, MTP remains a much less convenient and versatile protocol compared to UMS, although it is certainly a step up from the mutually incompatible proprietary protocols of yesteryear.
It should be borne in mind that the implementation of the MTP protocol may differ for different players: some may not support copying files or PlayFromDevice, may not be visible in the "My Computer" window, etc.
Portable digital players certified by P4S. The main requirements for such devices are support for the MTP protocol and playing files protected by Janus DRM. There is also a set of other requirements for performance, management, etc.
An unpleasant fact is the policy of "tightening the screws" that Microsoft has been practicing lately with regard to the capabilities of P4S players. So, manufacturers of P4S players have the right to implement in their devices, along with MTP support, also USM support. But the second version of the P4S specification requires manufacturers to remove from their players the ability to manually select by the user between using the MTP or UMS protocol. Now all P4S players should automatically detect if the system has MTP support, and if it is detected, they should be defined exclusively as MTP devices.
On the other hand, the functional improvement of the devices is encouraged: the same version of the specification rewards players with additional points for the best on / off times, transitions between tracks, support for Gapless playback, Album Art.
On the pageplaysforsure. comyou can find a wide selectionP4 S-certified devices
In general, this DRM system is vertically integrated from the purchase of content to its exploitation and is similar in this respect to iTunes. It is not for nothing that it is the main rival of FairPlay in the struggle for the online music market. P4S is a coalition scheme; today there are already quite a lot of participants in it. Despite this, its market share is still seriously inferior to FairPlay. This is not surprising: in the US, most players are iPods and they are incompatible with P4S, in Europe and Asia P2P networks are popular, which negatively affects online music sales.
P4 S-shops, although they do not occupy the last places, still seriously lag behindiTunes
All components of Windows Media DRM are constantly evolving. Today, PlaysForSure-specifications version 2.01 (3.0 should be released in 2007), Windows Media Player 11 (version 12 is expected next year), Windows Media DRM 10.1 (namely the 10th version is called Janus, the earlier, ninth, simply referred to as WM DRM PD).
In addition to these two main players, Sony should be mentioned, which, as usual, chose to go its own way and developed its own DRM algorithms.
Open MG
This DRM scheme is proprietary and used by Sony for its vertically integrated digital content distribution system. The latter includes:
Shop online digital music SonyConnect.
Weak salesSonyConnecteven the management of the company itself admitted
Audio formatATRAC3 , also owned by Sony, used to store content. ATRAC3 files are encoded using the OpenMG algorithm with a key called the Content Key. This key is then in turn encoded with the Storage Key. The encoded Storage Key is stored in the header of the ATRAC file. Thus, the OpenMG system assumes the joint delivery of the key and content.
ATRAC -one of the oldest audio formats
License... In this regard, Sony's technology is similar to Microsoft's DRM. Each unit of OpenMG content comes with a license containing the rules and restrictions for the user. Unlike Microsoft DRM licenses, the OpenMG license does not contain a key.
Computer softwareSonicStage used to transfer files to portable players. Each copy of SonicStage, as well as each OpenMG-compatible player, has its own Session Key, with which they are mutually authorized. If the authorization is successful, its participants pass each other a Storage Key, which is used to decode the Content Key, which in turn is used to decode the content. This program has been the object of constant criticism in recent years. For a long time, when writing MP3 files to the player, she converted them to ATRAC3 format and encoded using OpenMG DRM. This, firstly, reduced the quality of the tracks, and secondly, seriously increased the data transfer time. There were also frequent cases of failures in which people lost all their data stored in the SonicStage library.
Splash ScreenSonicStage 4.0
Openmg-compatible players... Today, these are exclusively Sony Walkman players on CDs, hard drives and built-in flash memory. In the early 2000s, Sony offered Memory Stick players. These memory cards have been protected by their hardware DRM mechanism called MagicGate. This DRM scheme has been used by Sony in other devices, such as the PlayStation 2 and PlayStation Portable game consoles.
In 2006Sonybegan to produce more interesting models, which is even more important, at a reasonable price, to support formatsMP3, WMAandAAC... Yet its market share is far from desired.
OpenMG is a cross between FairPlay, due to the fact that it is used exclusively by Sony itself, and PlaysForSure, due to the greater versatility in terms of the assignment of rules and restrictions, and the use of licenses.
In terms of imposing copyright restrictions, Sony Corporation (which, by the way, includes the world's largest record company and film studio) has always been among the pioneers. As a result, she also gets a significant portion of the negative attitude of users to this limitation.
The harshly curtailed user rights in SonicStage, in particular, have created a very negative reputation for this program; in fact, this program has become the standard of poor software manager for digital players. OpenMG and MagicGate DRM technologies also received their portion of criticism. Today OpenMG is one of the least common DRM systems and lags far behind Microsoft's DRM and even more so FairPlay.
Another DRM scheme worth mentioning is not directly related to digital players, but directly affects digital music and video.
OMA DRM
OMA's DRM scheme, as its name suggests, was developed by the Open Mobile Alliance to protect mobile content, primarily ringtones and their derivatives. MP3 players with support for this type of DRM have not yet been seen, although some platform manufacturers have announced such optional features.
In 2006, the volume of the world market for ringtones should exceed $ 5 billion, which will be more than 10% of world sales of music in any form.
The first version of OMA DRM appeared in 2002. It included three models, two of which, Forward Lock and Combined Delivery, assumed the joint delivery of the key and encrypted content to the consumer, and the third, Separate Delivery, was separate.
Forward Lock and Combined Delivery provided for a complete ban on any copying of the protected object from the device on which the purchase was made. Combined Delivery differed from Forward Lock in the ability to assign rights and restrictions for the user, for example, the maximum number of content plays.
Separate Delivery provided for separate delivery of encrypted content and a package containing the key and user rights. This scheme resembles Microsoft's DRM licenses. The main advantage of this system is the possibility of further distribution of content - the user has the ability to send it to other phones. Their owners will be able to play them only after receiving the key, which, together with the rights, they need to purchase from the provider. It's hard to say whether anyone will be happy to receive content for which you need to pay money, while receiving a bunch of restrictions on its use, but Separate Delivery provides such an opportunity.
GeneralschemeOMA 1.0SeparateDelivery
The second version of OMA DRM, announced in 2004, is an evolution of the Separate Delivery model. In particular, the new version uses public key encryption. The object, including the key required to decode the content and user rights, is encrypted with the public key. In this case, the secret key is stored in the user's device. Thus, only that device will be able to decode this object in order to gain access to the key needed to decrypt the content. Other innovations include: the emergence of the concept of a domain, a set of devices that can freely exchange content among themselves (for this purpose, a new key is introduced, called the Domain key), the ability to preview (preview) content, purchase content "in bulk" (the so-called Bundle ), the ability to purchase content by subscription.
It is easy to see that OMA DRM, in fact, embodies the dream of the record companies: a completely dense system, which does not want to hear anything about any Fair Use, and severely restricts user rights. Its harshness is mitigated by the unnecessary use: many providers of ringtones and other content distribute their product DRM-free. For a long time, the recording industry did not take ringtones seriously and did not insist on the mandatory use of DRM in their distribution. However, with the advent of realtones, which are not much inferior in quality to MP3-records, the situation began to change. On the other hand, OMA 2.0 is already significantly more liberal towards the user than the first version. In any case, it is clear that the Open Mobile Alliance is far more successful on DRM than SDMI.
The listed DRM systems are among the most commonly found in portable digital devices. There are other schemes that are less common.
Other
ZuneDRM... To everyone's surprise, Microsoft did not use the scheme that PlaysForSure had painstakingly built for so long in its player, but developed a new one. So far, little is known about her. Its most striking manifestation is that it automatically embeds all files transferred over Wi-Fi, and deletes them after three days or after three listens. The new DRM is being talked about as part of Microsoft's long-term strategy for the commercial exchange of music between users. In any case, such an act by Microsoft at first glance looks very strange - the PlaysForSure clientele of online services is deprived of the opportunity to listen to their music on the new player. On the other hand, this behavior is understandable if the company intends to copy Apple's business model - a rigid vertically integrated system from its own online service, software and player. In this case, a stricter, tougher and more efficient DRM system is required. However, at the expense of what resources Microsoft is going to repeat Apple's success - it is still unclear.
Thanks toDRMthe result of the exchange of these twoZunelive no more than three days (photo from www.haaretz.com)
Helix DRM... RealNetworks was at the forefront of commercial Internet audio, but its formats and solutions could not compete with the more common MP3, AAC, WMA, OGG. In early 2004, she launched a new online music service offering AAC content protected by her DRM development Helix. The only Helix-compatible device is the Creative Zen Xtra. The store has had very limited success, not least due to its incompatible DRM. This caused RealNetworks to show some rather dubious originality and develop Harmony technology, which converted the encoded Helix files to FairPlay or WM-DRM protected format. In retaliation, Apple modified its DRM system. Since then, a kind of race has been constantly going on between the companies: Apple changes its DRM, RealNetworks, in response, makes changes to the Harmony technology. There are no new devices that support DRM Helix itself.
CreativeZenXtra- the only player with supportHelixDRM
KoreanDRM-systems... South Korea has a number of its own online music selling services. Some of them use the PlaysForSure system, but there are also a number of national developments, in particular, X-sync, Mediarose, Netsync. There is very little information about them on the non-Korean Internet.
DRM Perspective
There are probably no people on this side of the counter today who would approve of DRM technologies as they are today.
First, DRM severely restricts the use of legally purchased content. An absurd situation arises when people, having paid money, receive significantly less opportunities and a level of convenience than people downloading content illegally.
Secondly, the exploitation of DRM-protected files is often accompanied by failures, unforeseen situations, fraught with loss of content.
Finally, sellers of music and video using DRM are in fact openly declaring that they consider all their buyers to be potential scammers, whose opportunities should be limited as much as possible. No wonder the main metaphors used by the anti-DRM community are "prison" and "concentration camp".
OpponentsDRMactively use the "left", liberal rhetoric and style (poster of the groupCRFTRwww.crftp.com)
All these negative emotions are caused by the DRM concept itself. What can we say about the situation when there are several incompatible DRM schemes on the market at the same time! Users of iPods, PlaysForSure and OpenMG players who purchase content from their respective online services cannot leave the boundaries of digital prisons erected by manufacturers without losing their entire music library, which is often much more expensive than any player. We should not forget about the growing market for music phones - only a few of these phones are compatible with FairPlay or PlaysForSure DRM.
Criticism of the current state of affairs sounds from all sides. Many do not limit themselves to words, but actively fight DRM. All existing DRM schemes have already been hacked many times, “cures” that allow the user to get rid of DRM protection in their files are widely available on the Internet.
Severe restrictions on existing DRM schemes and their incompatibility are considered the main reason for the crisis in online sales of digital content in 2006. More and more users choose illegal downloading via P2P networks - not only because of the free, but also because of the convenience.
US digital music online sales stagnated in 2006 (dataNielsenSoundScan)
DRM-free online sales are called the outlet for the industry. The example is an online store eMusic, which, by selling exclusively music produced by small independent record companies, was able to climb to the second place after iTunes in terms of sales. This service offers regular MP3 files without DRM protection. Voices calling to stop treating customers as criminals and artificially restrict the use of honestly purchased goods have been growing louder lately.
Offering the music of independent record labels withoutDRM, eMusicin December 2006 sold her 100 millionth track
The fact remains that modern DRM schemes demonstrate their non-competitiveness. Digital content sales are stagnating, and illegal P2P networks continue to occupy up to 90% of the global online music market. The way out for the industry can be either the creation of a fundamentally different concept of DRM, or a complete rejection of attempts to protect the rights to digital content.
In this tutorial I will show you how to set up an android using the Philips Xenium W3568 phone as an example. In this article I will tell you about the rest of the menu items, as well as how to enable the item for developers.
Moving on to the location data.
In the location data tab, you can enable access to my location data and allow applications to use your location data. You can select sources of GPS satellites location data. Also set by network coordinates, that is, allow sending anonymous geodata and let applications determine your location using Wi-Fi and mobile networks.
In the security tab, you can set the screen lock, by default it is worth swiping, but I recommend setting the lock type more serious and more reliable.
You can select the type of lock: voice unlock, pattern, PIN, password. I will choose a pattern.
Now create a pattern by sketching with lines.
I drew the letter M. Press continue.
Re-draw the pattern to confirm. Then press confirm.
Also, in the security tab, you can set auto-blocking after a certain amount of time. First, the display turns off and then the auto-lock is turned on. You can set the display to turn off for 2 minutes and auto-lock after 2 minutes. Thus, as soon as the screen turns off, the screen lock turns on, that is, in order to enter the smartphone, you will need to draw the pattern that we created earlier.
You can also encrypt data. Requests a numeric PIN or decryption password each time the phone is switched on. Set up a screen lock.
In the security tab, you can set device administrators to remotely block and erase information from your smartphone, in case your smartphone is stolen and you do not want a thief to gain access to your data on your smartphone.
Click activate to enable the ability to delete all data on the phone by factory reset. Also, to change the password to unlock the screen. Lock the screen.
Enable or disable the installation of applications from unknown sources... By default, you can install applications only from the Play Market, but if you enable "unknown sources", then applications can be installed both from the SD card and from the Internet. For safety, enable this checkbox only when you want to install applications from an SD card and disable it after they have been installed. You do not need to leave this option enabled, so that when I surf the Internet, you do not accidentally install any malicious application.
Also keep the checkbox on "check applications" enabled to prohibit the installation of applications that may harm the device, or warn about them.
In the language and input tab, you can select the interface language, enable spell check, TouchPal keyboard (allows you to type in letters and speeds up the typing).
In the restore & reset tab, you can back up your app data, Wi-Fi hotspot passwords, and settings to Google servers. Set up a backup account with data backups. Install auto-recovery, when reinstalling the application, restore a backup copy of the settings and data. Reset DRM, that is, remove all DRM licenses.
Also here you can reset smartphone settings... Delete all data from your smartphone and make your smartphone like a store.
Resetting the settings will delete all data from the internal memory of the device, including: your Google account, settings / data of the system and applications, downloaded applications.
In the Google Accounts tab, you can sync and transfer data from your smartphone to your Google account.
You can transfer your letters from the mailbox, data from the browser, application data, calendar, contacts to your Google account. Thus, when you change your smartphone to another, it will be enough to use the same Google account as on the previous device to transfer all your contacts from the old smartphone to the new one.
In the date and time tab, you can set the date and time manually or try using the network time zone (but this garbage does not work, so I recommend setting the date and time manually).
In the tab, the on and off schedule can be set when the smartphone will turn on and when it will turn off (for example, at night, you can make an automatic shutdown and turn on in the morning).
In the accessibility tab, you can set up gestures for magnification, large text, auto-rotate the screen, and speak passwords.
DRM is an intellectual property protection tool that allows the copyright holder to control access, preventing unauthorized copying and distribution of software. The technology is used on various products, including mobile operating systems, so users periodically have a question about what is a DRM license reset on Android.
What is DRM
DRM is an acronym for Digital Rights Management, which can be translated as digital rights management. Management is implemented through the placement of various technical means into the product that prevent the illegal disposal of the software. The owner can use the protected product only for personal purposes, he will not be able to copy it and sell it. In fact, DRM is a kind of digital lock, the key to which must be purchased from the copyright holder.
The DRM key for gaining access is presented in the form of a code, during the creation of which cryptoalgorithms are used. Hacking it is very difficult, and you can get it only after purchasing a digital product with a license. On Android, the technology is often implemented as follows:
- A person buys a new device into which the manufacturer pre-installs certain software.
- After turning on and activating the device, the software starts working for free in demo mode. After the trial period expires, the application ceases to function, requiring the purchase of a license.
Buying access to the full version of the software is the DRM element. This is just one of the possible options, there are other examples of copyright protection.
The procedure for resetting DRM differs depending on what the license covers. For example, using hacker software, you can reset the program launch counter, unlink files from the site, disable key verification, and perform other actions to unlink the license. As for Android, here the reset can be done without hacking software.
Use this function with extreme caution, because after resetting the license, you may lose access to certain product features. DRM keys are required to run special applications from the phone manufacturer. You can find such programs on Sony, Samsung, etc. After resetting the key, branded applications may stop working, but the rest of the functionality of the phone will remain the same.
It has nothing to do with the refusal of the license. If, when rolling back the settings, all applications installed by the user, as well as personal data, are removed from the phone, then removing the license only disables the software built by the manufacturer.
If you want to know what requirements different applications have, what programs will be affected by removing licenses, whether the device supports technologies that are needed for the normal functioning of services, then install DRM Info on your mobile device. The application displays information about the DRM components, at the same time indicating whether they are supported on devices. 
Why do we need this information? To understand if it is worth buying premium accounts or licensed apps. For example, Full HD and 4K video playback on Netflix requires Google Widevine Level 1. Most devices come with the third level, so there is no point in spending money on a premium account, because there will be no quality improvement - the device does not support the required technologies.
