About Jailbreaking , Cydia
What's Cydia ?
Cydia ( /sɪˈdi.ə/) is a software application for iOS that enables a user to find and install software packages (including apps, interface customizations, and system extensions) on a jailbroken iPhone, iPod Touch or iPad. Cydia is the main independent third-party digital distribution platform for software on iOS.[2]Many of the software packages available through Cydia are free, and it also includes several hundred packages for sale through the Cydia Store payment system with a commission setup similar to the App Store.[3] Most of these packages focus on providing customizations and modifications (often called "tweaks") that can only run on jailbroken devices (since the App Store is limited to distributing self-contained apps).[4]
Cydia is a graphical front end to Advanced Packaging Tool (APT) and the dpkg package management system, which means that the packages available in Cydia are provided by a decentralized system of repositories (also called sources) that list these packages.[5]
Cydia is developed by Jay Freeman (also called "saurik") and his company, SaurikIT.[1] The name "Cydia" is an allusion to the Codling Moth, with a scientific name of Cydia pomonella, which is the proverbial "worm in the apple."[6]
.(From Wikipedia )
Purpose and Function
Cydia provides a graphical user interface to jailbroken iOS users using APT repositories to install software unavailable on the App Store. Since Cydia is based on APT (ported to iOS as part of Freeman's Telesphoreo project),[5] it is a repository aggregator that avoids dependence on one host and comes with a few trusted default sources. Many stable packages are available on these repositories, and additional repositories can be easily added. This enables the iOS development scene to stay as open as possible; anyone with a server can set up, host, manage, and update their own repository and share it with the community. The default sources accept package submissions, which helps packages gain more exposure than if they were hosted on separate repositories.
Software packages are downloaded directly to an iOS device, to the same location as Apple's pre-installed applications, the /Applications directory. Jailbroken devices can also still buy and download apps normally from the official App Store.[7]
Cydia is installed during the process of jailbreaking an iOS device.[6] Jailbreaking tools (each of them supporting a specific set of devices and iOS versions) including ZiPhone, JailbreakMe, QuickPwn, redsn0w, purplera1n, blackra1n, limera1n, Greenpois0n, and Absinthe include the option to install Cydia while jailbreaking or install Cydia automatically while jailbreaking, and Cydia can also be installed by restoring a custom jailbroken firmware created by the jailbreaking tools PwnageTool, sn0wbreeze or redsn0w.
Software available on Cydia
Some of the packages available through Cydia are standard applications, but most of the packages are extensions and modifications for the iOS interface and for apps in the iOS ecosystem. Since these software packages run on jailbroken devices, they can provide functionality outside the scope of normal applications — such as system-wide changes to the user interface, new features inserted into existing apps, customizations of button actions, extensions of networking behavior, and other "tweaks" to the system. Users install these for purposes including personalization and customization of the interface,[8] adding desired features and fixing annoyances,[9] and making development work on the device easier by providing access to the filesystem and command-line tools.[10][11] Most of the packages available through Cydia are written by independent developers.
Popular packages in Cydia include Winterboard (which lets users "skin" the iOS interface and app icons with themes),[12] MyWi (enable Wi-Fi tethering),[4]SBSettings (access settings and controls with a gesture),[13] Barrel (stylize the animated transition between SpringBoard pages),[14] and DisplayOut (display the device's screen on a connected TV or monitor).[15] Many extensions available through Cydia are based on a framework called MobileSubstrate, developed by Freeman, which makes the process of writing and maintaining system modifications easier.[6]
Since packages in Cydia are not limited by the iOS app security sandbox, journalists recommend using "the same vigilance you use when considering a program for your computer," including learning about the developer who wrote the package, before installing it.[4]
Cydia Store
In March 2009, Freeman introduced a simple, unified payment system that allows software developers to sell packages inside of Cydia (with user purchases linked to user accounts), much like the official App Store. Users may use Amazon Payments or PayPal to purchase items within Cydia.[16] The proof of payment is linked to a Google or Facebook account in case users move to a new iOS device or restore the device; users can log in and install all their previously-purchased packages without having to buy them again.[17]
Most of the packages for sale within Cydia use the Cydia Store payment system, with Cydia taking a 30% cut that includes covering PayPal fees and server costs.[18] Developers are not required to use the Cydia Store system to charge for their software; some paid packages, such as LockInfo and biteSMS, must be registered separately from the Cydia Store through the developers' own means.
iOS Signature Feature
In addition to offering software to install, in September 2009 Cydia was improved to help users have the option to downgrade (or upgrade) their device to versions of iOS not currently allowed by Apple. Cydia caches the digital signatures called SHSH blobs used by Apple to verify restores of iOS (which Apple uses to limit users to only installing the latest version of iOS).[19] Cydia's storage mechanism enables users to downgrade a device to a prior version of iOS by means of a replay attack.[20] This means, for example, that a person with a jailbroken device who upgrades to a non-jailbreakable version of iOS can choose to downgrade back to a jailbreakable version.[21]
iOS 5.0 and later versions of iOS implement an addition to the SHSH system, a random number (a cryptographic nonce) in the "APTicket", making it more difficult to perform a replay attack.[22] Versions ofredsn0w after 0.9.9b9 include a way to save the APTicket so that SHSH and APTicket can be replayed later.[23]
Jailbreak Platform
Using Cydia depends on having a jailbroken device. In the U.S.A. Jailbreaking the iPhone was a legal grey area[24] until July 2010, when the U.S. Copyright Office declared a Digital Millennium Copyright Actexemption making jailbreaking the iPhone legal.[25] Apple policy is that jailbreaking voids the device warranty (although detecting previous jailbreaks on a restored device may be difficult or impossible), and that unauthorized software can cause the device to be less stable.[9]
Jailbreaking is normally done via applications on a computer such as redsn0w (or other tools), but a website named JailbreakMe was used for iOS 4.3.3 and jailbroke the device through the web browser on the device itself (Safari).
iOS Jailbreaking
iOS jailbreaking is the process of removing the limitations imposed by Apple on devices running the iOS operating system through the use of hardware/software exploits — such devices include the iPhone,iPod touch, iPad, and second generation Apple TV. Jailbreaking allows iOS users to gain root access to the operating system, allowing them to download additional applications, extensions, and themes that are unavailable through the official Apple App Store. Jailbreaking is a form of privilege escalation, and the term has been applied to privilege escalation on other computer systems as well. The name refers to breaking the device out of its "jail",[1] which is a technical term used in Unix-style systems, for example in the term "FreeBSD jail". A jailbroken iPhone, iPod touch, or iPad running iOS can still use the App Store, iTunes, and other normal functions, such as making telephone calls.
Unlike rooting an Android device, jailbreaking is necessary if the user intends to run software not authorized by Apple. Under the Digital Millennium Copyright Act, jailbreaking iPhones is legal in the United States, although Apple has announced that the practice "can violate the warranty".[2]
Reasons for Jailbreaking
Added features and customizations
One of the main reasons for jailbreaking is to expand the feature set limited by Apple and its App Store. Most jailbreaking tools automatically install Cydia, an
ative iOS APT client used for finding and installing software for jailbroken iOS devices.[3] Since software programs available through Cydia are not required to adhere to App Store guidelines, many of them are not typical self-contained apps but instead are extensions and customizations for iOS and other apps.[4] Users install these programs for purposes including personalization and customization of the interface,[4] adding desired features and fixing annoyances,[5] and making development work on the device easier by providing access to the filesystem and command-line tools.[6][7]
Use of handset on multiple carriers
Jailbreaking also opens the possibility for using software to unofficially unlock carrier-locked iPhones so they can be used with other carriers.[8] Software-based unlocks have been available since 2008,[9] with each tool applying to a specific iPhone model and baseband version (or multiple models and versions)
Reasons for Jailbreaking
Apps denied App Store approval
Some users look to software outside the App Store to express opposition to Apple's control of content through the app approval process: in early 2010, Apple denied an app submitted by Pulitzer Prize-winning cartoonist, Mark Fiore, because it "ridiculed public figures", in violation of Section 3.3.14 of the iPhone Developer Program License Agreement. Apple later called Fiore and asked him to resubmit his app for approval.[11] In late 2010, Apple banned the use of apps that allowed users to donate money to non-profit organization and charities.[12] Apple also denied a WikiLeaks app, stating it "violated their developer guidelines".[13] As the list of banned apps continues to grow, some users have found jailbreaking to be a viable alternative to Apple’s censorship of content.[14]
Installing software published outside the App Store has the potential to affect battery life and system stability if the software is poorly optimized or frequently uses resource-draining services (such as 3G or Wi-Fi)
History of Jailbreaking
A few days after the original iPhone became available in July 2007, developers released the first jailbreaking tool for it,[32] and soon a jailbreak-only game app became available.[33] In October 2007,JailbreakMe 1.0 (also called "AppSnapp") allowed people to jailbreak iPhone OS 1.1.1 on both the iPhone and iPod touch,[34][35] and it included Installer.app as a way to get software for the jailbroken device. In February 2008, Zibri released ZiPhone, a tool for jailbreaking iPhone OS 1.1.3 and 1.1.4.[36]
"Pwnapple" icon used by redsn0w andPwnageTool. (See Pwn.)
The iPhone Dev Team has released a series of free desktop-based jailbreaking tools. They released a version of PwnageTool in July 2008 to jailbreak the new iPhone 3G on iOS 2.0 as well as the iPod touch,[37][38] newly including Cydia as the primary third-party installer for jailbroken software[39] (PwnageTool continues to be updated for untethered jailbreaks of newer iOS versions).[40][41] The iPhone Dev Team released QuickPWN to jailbreak iOS 2.2 on iPhone and iPod touch, also including options to enable functionality that was possible but disabled by Apple on certain devices.[42] After Apple released iOS 3.0, the Dev Team published redsn0w as a simple jailbreaking tool usable on Mac and Windows, and also updated PwnageTool (now primarily intended for expert users making custom firmware, and only for Mac).[43]
History of Jailbreaking
They continue to maintain redsn0w for jailbreaking most versions of iOS 4 and iOS 5 on most devices.[44] As of December 2011, redsn0w includes the "Corona" untether by pod2g for iOS 5.0.1 for iPhone 3GS, iPhone 4, iPad 1, and iPod touch 3rd and 4th generation.[41] As of June 2012, redsn0w also includes the "Rocky Racoon" untether by pod2g for iOS 5.1.1 on all iPhone, iPad, and iPod touch models that support iOS 5.1.1.[45]
George Hotz, who had developed the first iPhone unlock, released a jailbreaking tool for the iPhone 3GS on iOS 3.0 called purplera1n,[46] and blackra1n for iOS version 3.1.2 on the iPod touch 3rd generation and other devices.[47] In October 2010 he released limera1n, a low-level boot ROM exploit that permanently works to jailbreak the iPhone 4 and is used as part of tools including redsn0w.[48]
History of Jailbreaking
Comex has released multiple jailbreaks for iOS devices, beginning in May 2010 with the Spirit jailbreak for iOS version 3.1.2 on devices including the iPad for the first time.[49] In August 2010, comex releasedJailbreakMe 2.0, a web-based tool that was the first to jailbreak the iPhone 4 (on iOS 4.0.1).[50][51] In July 2011, comex released JailbreakMe 3.0, a web-based tool for jailbreaking all devices on certain versions of iOS 4.3, including the iPad 2 for the first time (on iOS 4.3.3).[52] JailbreakMe 3.0 uses a flaw in PDF file rendering in Mobile Safari.[53][54] He was hired by Apple as an intern in August 2011.[55]Chronic Dev Team initially released greenpois0n in October 2010, a desktop-based tool for jailbreaking iOS 4.1[56] and later iOS 4.2.1[57] on most devices including the Apple TV,[58] as well as iOS 4.2.6 on CDMA (Verizon) iPhones.[59]
The iPhone Dev Team, Chronic Dev Team, and pod2g collaborated to release Absinthe in January 2012, a desktop-based tool to jailbreak the iPhone 4S for the first time and the iPad 2 for the second time, on iOS 5.0.1 for both devices and also iOS 5.0 for iPhone 4S.[29][30][60][61] In May 2012 they released Absinthe 2.0, which can jailbreak iOS 5.1.1 untethered on all iPhone, iPad, and iPod touch models that support iOS 5.1.1, including jaibreaking the third-generation iPad for the first time.[62]
Types of Jailbreak ( Tethered and Untethered )
When a device is booting, it loads Apple's own kernel initially. The device must then be exploited and have the kernel patched each time it is turned on.
An untethered jailbreak has the property that if the user turns the device off and back on, the device will start up completely, and the kernel will be patched without the help of a computer — in other words, it will be jailbroken after each reboot.[29]
With a tethered jailbreak, if the device starts back up on its own, it will no longer have a patched kernel, and it may get stuck in a partially started state; in order for it to start completely and with a patched kernel, it essentially must be "re-jailbroken" with a computer (using the "boot tethered" feature of a jailbreaking tool) each time it is turned on.[30]
A device with a tethered jailbreak may be able to have a semi-tethered solution, which means that when the device starts up on its own, it will no longer have a patched kernel (so it will not be able to run modified code), but it will still be usable for normal functions.[31] With a semi-tethered solution, the user can also choose to start the device with the help of the jailbreaking tool in order for it to start with a patched kernel (jailbroken).
Jailbreak available
- iOS 4.0 through 4.0.2 : Untethered Jailbreak using Limerain .
- iOS 4.1 through 4.2.1 : Untethered Jailbreak using Redsnow , Greenpoison .
- iOS 4.2.6 through 4.2.8 , 4.3 through 4.3.3 : Untethered Jailbreak using Jailbreakme .
- iOS 4.2.9-10 , 4.3.4-.4.3.5 : Tethered Jailbreak using Greenpoison .
- iOS 5.0 : Untethered Jailbreak ( iPad 2 , iPhone 4S ) using Absinthe . Tethered Jailbreak on another devices !
Jailbreak available
- iOS 5.0.1 : Untethered Jailbreak using Absinthe ( iPhone 4S , iPad 2 ) . Untethered Jailbreak using Redsnow + Corona .
- iOS 5.1 : Tethered Jailbreak using Redsnow for A4 Devices .
- iOS 5.1.1 : Untethered Jailbreak using Absinthe 2.0 through Absinthe 2.0.4 ( Greenpoison )
The End :D !
Have a nice day !