Nonce - Revision history

DanTheMann15: add a little more info.

2021-12-06T07:15:24Z

add a little more info.

DanTheMann15: More info

2021-05-05T04:00:21Z

More info

5ynt4x 3rr0r at 00:08, 5 May 2021

2021-05-05T00:08:46Z

AS967 at 03:06, 10 September 2017

2017-09-10T03:06:02Z

AS967 at 03:11, 16 January 2017

2017-01-16T03:11:47Z

AS967 at 14:54, 18 December 2016

2016-12-18T14:54:47Z

AS967 at 12:27, 28 July 2016

2016-07-28T12:27:52Z

AS967 at 18:19, 21 July 2016

2016-07-21T18:19:56Z

IAdam1n: Updating

2015-10-12T10:09:33Z

Updating

IAdam1n: /* BBTicket */ It is not a "2G".

2014-10-05T13:47:35Z

‎BBTicket: It is not a "2G".

@@ Line 2: / Line 2: @@
 ==Method==
-The device's bootloaders (firmware, baseband and SEP) generate a random value (generator) which is then hashed to create the boot nonce (BNCH).
+The device's bootloaders (firmware, baseband and SEP) generate a random value using a nonce seed (generator) which is then hashed to create the boot nonce hash (BNCH).
 During a Restore or Update, the generated numbers are sent to Apple's [[Tatsu Signing Server|TSS Server]] along with the device's [[ECID]] and the hashes of the firmware components to be signed.
@@ Line 8: / Line 8: @@
 If apple is signing the requested firmwares, the TSS Server sends the APTicket/BBTicket/SEPTicket with the certificates matched to the generated nonces for each firmware, and then the blobs are stitched into the firmware files. It is important that the nonces inside the blobs are matched to the nonces generated by the device, if the nonces inside the blobs don't match the device's bootloaders will reject the certificates and the restore will not be successful.
-With the [[T8020]] and all newer chipsets, the BNCH is also encrypted with the devices's [[UID key]], which further randomizes the boot nonce, this is known as "Nonce Entangling".
+With the [[T8020]] and all newer chipsets, the BNCH is also encrypted with the devices's [[UID key]], which further randomizes the boot nonce, this is known as "[[Nonce#Nonce_Entangling|Nonce Entangling]]".
 ==Usage==
@@ Line 26: / Line 26: @@
 ===Nonce Entangling===
-Nonce Entangling on [[T8020]] and all newer CPU's makes saving a reusable APTicket with the proper BNCH more difficult, as the boot nonce generated is also encrypted with the device's UID key. Getting around this requires finding-out what nonce is actually generated by the selected generator you are using, which usually requires a [[Jailbreak]] with a nonce-setter.
+Nonce Entangling on [[T8020]] and all newer CPU's makes saving a reusable APTicket with the proper BNCH more difficult, as the boot nonce generated is also encrypted with the device's UID key. Getting around this requires finding-out what nonce is actually generated with the  nonce seed you are using, which usually requires a [[Jailbreak]] with a nonce-setter or you can use airsquared's [https://github.com/airsquared/blobsaver blobsaver] to read the nonce/generator from the device.
 Another possible attack is to put your device into [[Recovery Mode]], get the generated boot nonce with [https://github.com/libimobiledevice/libirecovery irecovery] or [https://github.com/tihmstar/igetnonce igetnonce], then update or restore your device to a signed firmware while still in recovery mode and then do not update/restore your device until you can jailbreak and dump [[iBoot]] to get the IM4R (nonce generator).
@@ Line 32: / Line 32: @@
 ==See also==
 *[[AT+XNONCE]]

@@ Line 1: / Line 1: @@
-'''Nonce''' is a signing method that randomizes Apple's cryptographic signature hash blobs ([[SHSH]] blobs) and is used with the BBTicket (baseband signing ticket), the APTicket (firmware signing ticket), and SEP ([[Secure Enclave]]). A12 and newer use a technique known as 'Nonce Entangling' making it harder to save blobs.
+A '''Nonce''' (''"Number-used-ONCE"'') is a randomly-generated number that is used to randomize the signed hash blobs ([[SHSH]] blobs) that Apple uses to sign firmwares.<br/>it is used with the APTicket (firmware signing ticket), the BBTicket ([[baseband]] signing ticket), and the SEPTicket ([[Secure Enclave|SEP]] signing ticket).
 ==Method==
 ==Usage==
@@ Line 15: / Line 21: @@
 *Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]] and [[S5L8940]] got [[SHSH]] blobs without APTicket between 3.0 - 4.3.5, and they can not be avoided (except for the [[Bootrom 359.3]] with the 0x24000 Segment Overflow)
 *Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]], [[S5L8940]], [[S5L8942]], [[S5L8945]], [[S5L8950]], and [[S5L8955]] get APTicket SHSH blobs on 5.0+. The SHSH requirement can not be avoided (except for the [[Bootrom 359.3]] with 0x24000 Segment Overflow), and the APTicket requirement can only be avoided on devices vulnerable to the [[limera1n Exploit]], or if the device is on iOS 5.1.1 or lower.
-*Devices with the [[S5L8960]], [[S5L8965]], [[T7000]], [[T7001]], [[S7002]], [[S8000]], [[S8001]], [[S8003]], [[T8010]], and [[T8011]] get APTickets exclusively (with SepNonce, which also needs to match) and they cannot be avoided, but can be utilized with the prometheus method.
+*Devices with the [[S5L8960]] and newer [[Application processor|CPU]]'s get APTickets exclusively (with SepNonce, which also needs to match) and they cannot be avoided, but can be utilized with the prometheus method.
 ==Jailbreak difficulties==
 With nonce signatures, signatures can't be cached, because signatures will not match if they have been reused. In other words, the widely used replay attack is no longer possible unless the nonce(s) (SepNonce + ApNonce on 64 bit, ApNonce only on 32 bit) the device generates matches the one on the APTicket.
 ==See also==

← Older revision		Revision as of 00:08, 5 May 2021
Line 1:		Line 1:
−	'''Nonce''' is a signing method that randomizes Apple's cryptographic signature hash blobs ([[SHSH]] blobs) and is used with the BBTicket (baseband signing ticket), the APTicket (firmware signing ticket), and SEP ([[Secure Enclave]]).	+	'''Nonce''' is a signing method that randomizes Apple's cryptographic signature hash blobs ([[SHSH]] blobs) and is used with the BBTicket (baseband signing ticket), the APTicket (firmware signing ticket), and SEP ([[Secure Enclave]]). A12 and newer use a technique known as 'Nonce Entangling' making it harder to save blobs.

	==Method==		==Method==

@@ Line 15: / Line 15: @@
 *Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]] and [[S5L8940]] got [[SHSH]] blobs without APTicket between 3.0 - 4.3.5, and they can not be avoided (except for the [[Bootrom 359.3]] with the 0x24000 Segment Overflow)
 *Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]], [[S5L8940]], [[S5L8942]], [[S5L8945]], [[S5L8950]], and [[S5L8955]] get APTicket SHSH blobs on 5.0+. The SHSH requirement can not be avoided (except for the [[Bootrom 359.3]] with 0x24000 Segment Overflow), and the APTicket requirement can only be avoided on devices vulnerable to the [[limera1n Exploit]], or if the device is on iOS 5.1.1 or lower.
-*Devices with the [[S5L8960]], [[S5L8965]], [[T7000]], [[T7001]], [[S7002]], [[S8000]], [[S8001]], [[S8003]], and [[T8010]] get APTickets exclusively (with SepNonce, which also needs to match) and they cannot be avoided, but can be utilized with the prometheus method.
+*Devices with the [[S5L8960]], [[S5L8965]], [[T7000]], [[T7001]], [[S7002]], [[S8000]], [[S8001]], [[S8003]], [[T8010]], and [[T8011]] get APTickets exclusively (with SepNonce, which also needs to match) and they cannot be avoided, but can be utilized with the prometheus method.
 ==Jailbreak difficulties==
 With nonce signatures, signatures can't be cached, because signatures will not match if they have been reused. In other words, the widely used replay attack is no longer possible unless the nonce(s) (SepNonce + ApNonce on 64 bit, ApNonce only on 32 bit) the device generates matches the one on the APTicket.

@@ Line 1: / Line 1: @@
-'''Nonce''' is a signing method that randomizes Apple's cryptographic signature hash blobs ([[SHSH]] blobs) and is used with the BBTicket (baseband signing ticket) and the APTicket (firmware signing ticket).
+'''Nonce''' is a signing method that randomizes Apple's cryptographic signature hash blobs ([[SHSH]] blobs) and is used with the BBTicket (baseband signing ticket), the APTicket (firmware signing ticket), and SEP ([[Secure Enclave]]).
 ==Method==
-The device bootloaders (baseband or firmware) generate a random number at the restore, then send them to iTunes which sends them to Apple. Then Apple sends the APTicket / BBTicket [[SHSH]] certificate with the number generated. This level is the most critical: the number within the certificate is matched to the number generated on device, and if they match iTunes will prepare the matched certificate and finally will stitch the randomized blobs to the firmware. If the blobs don't match the restore will fail and the bootloaders will reject the certificate.
+The device bootloaders (baseband, firmware, and SEP) generate a random number at the restore, then send them to iTunes which sends them to Apple. Then Apple sends the APTicket / BBTicket [[SHSH]] certificate with the number generated. This level is the most critical: the number within the certificate is matched to the number generated on device, and if they match iTunes will prepare the matched certificate and finally will stitch the randomized blobs to the firmware. If the blobs don't match the restore will fail and the bootloaders will reject the certificate.
 ==Usage==
@@ Line 15: / Line 15: @@
 *Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]] and [[S5L8940]] got [[SHSH]] blobs without APTicket between 3.0 - 4.3.5, and they can not be avoided (except for the [[Bootrom 359.3]] with the 0x24000 Segment Overflow)
 *Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]], [[S5L8940]], [[S5L8942]], [[S5L8945]], [[S5L8950]], and [[S5L8955]] get APTicket SHSH blobs on 5.0+. The SHSH requirement can not be avoided (except for the [[Bootrom 359.3]] with 0x24000 Segment Overflow), and the APTicket requirement can only be avoided on devices vulnerable to the [[limera1n Exploit]], or if the device is on iOS 5.1.1 or lower.
-*Devices with the [[S5L8960]], [[S5L8965]], [[T7000]], [[T7001]], [[S7002]], [[S8000]], [[S8001]], [[S8003]], and [[T8010]] get APTickets exclusively and they cannot be avoided.
+*Devices with the [[S5L8960]], [[S5L8965]], [[T7000]], [[T7001]], [[S7002]], [[S8000]], [[S8001]], [[S8003]], and [[T8010]] get APTickets exclusively (with SepNonce, which also needs to match) and they cannot be avoided, but can be utilized with the prometheus method.
 ==Jailbreak difficulties==
-With nonce signatures, signatures can't be cached, because signatures will not match if they have been reused. In other words, the widely used replay attack is no longer possible unless the nonce the device generates matches the one on the APTicket.
+With nonce signatures, signatures can't be cached, because signatures will not match if they have been reused. In other words, the widely used replay attack is no longer possible unless the nonce(s) (SepNonce + ApNonce on 64 bit, ApNonce only on 32 bit) the device generates matches the one on the APTicket.
 ==See also==

@@ Line 14: / Line 14: @@
 *Devices with the [[S5L8720]] get [[SHSH]] blobs without APTicket from 3.1.1 and on, even though [[Bootrom 240.4]] doesn't require them and they can be avoided with the [[0x24000 Segment Overflow]]
 *Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]] and [[S5L8940]] got [[SHSH]] blobs without APTicket between 3.0 - 4.3.5, and they can not be avoided (except for the [[Bootrom 359.3]] with the 0x24000 Segment Overflow)
-*Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]], [[S5L8940]], [[S5L8942]], [[S5L8945]], and [[S5L8950]] get APTicket SHSH blobs on 5.0+. The SHSH requirement can not be avoided (except for the [[Bootrom 359.3]] with 0x24000 Segment Overflow), and the APTicket requirement can only be avoided on devices vulnerable to the [[limera1n Exploit]], or if the device is on iOS 5.1.1 or lower.
+*Devices with the [[S5L8920]], [[S5L8922]], [[S5L8930]], [[S5L8940]], [[S5L8942]], [[S5L8945]], [[S5L8950]], and [[S5L8955]] get APTicket SHSH blobs on 5.0+. The SHSH requirement can not be avoided (except for the [[Bootrom 359.3]] with 0x24000 Segment Overflow), and the APTicket requirement can only be avoided on devices vulnerable to the [[limera1n Exploit]], or if the device is on iOS 5.1.1 or lower.
 *Devices with the [[S5L8960]], [[S5L8965]], [[T7000]], [[T7001]], [[S7002]], [[S8000]], [[S8001]], and [[S8003]] get APTickets exclusively and they cannot be avoided.
 ==Jailbreak difficulties==

@@ Line 7: / Line 7: @@
 ===BBTicket===
 *No iPod touch (or iPad Wi-Fi) has been signed with the BBTicket, since by definition it has no baseband.
-*[[M68ap|iPhone]] (bootloaders can be neutered to cancel this signchecks). [[N82ap|iPhone 3G]], [[N88ap|iPhone 3GS]] and [[K48ap|iPad Wi-Fi+3G]] - if the baseband is higher or equal (or just higher on bootloader 3.9 on iPhone 2G). Some bootloaders allow downgrade of the baseband if it is still signed.
+*[[M68AP|iPhone]] (bootloaders can be neutered to cancel this signchecks). [[N82AP|iPhone 3G]], [[N88AP|iPhone 3GS]] and [[K48AP|iPad Wi-Fi+3G]] - if the baseband is higher or equal (or just higher on bootloader 3.9 on [[M68AP|iPhone]]). Some bootloaders allow downgrade of the baseband if it is still signed.
-*[[N90ap|iPhone 4 (iPhone3,1)]], [[N92ap|iPhone 4 (iPhone3,3)]], [[N94ap|iPhone 4S]], and [[K94ap|iPad 2 (iPad2,2)]] and [[K95ap|iPad 2 (iPad2,3)]] - [[AT+XNONCE]] - restores the baseband only if Apple is still signing it. On bootloaders 2.8, 2.13, Trek and Phoenix, both the [[AT+XNONCE]] and the "higher or equal" checks happen.
+*[[N90AP|iPhone 4 (iPhone3,1)]], [[N92AP|iPhone 4 (iPhone3,3)]], [[N94AP|iPhone 4S]], and [[K94AP|iPad 2 (iPad2,2)]] and [[K95AP|iPad 2 (iPad2,3)]] - [[AT+XNONCE]] - restores the baseband only if Apple is still signing it. On bootloaders 2.8, 2.13, Trek and Phoenix, both the [[AT+XNONCE]] and the "higher or equal" checks happen.
 ===APTicket===