6,264
edits
Changes
Jump to navigation
Jump to search
Line 79:
Line 79: − + − * Decrypts arm9_bin_buf+0 using keyslot 0x11 with AES-ECB, and initialises keyX for keyslot 0x15 with it.+ − + − + + + + +
→New_3DS FIRM
* Checks u8 0x10000000 bit1 again, if it's set then it executes a panic function(set r0-r2=0, execute nop instruction, then execute instruction "bkpt 0x99"). Hashes data from the region [[IO_Registers|0x10012000-0x10012090]] using SHA256 via the [[SHA_Registers|SHA]] hardware.
* Checks u8 0x10000000 bit1 again, if it's set then it executes a panic function(set r0-r2=0, execute nop instruction, then execute instruction "bkpt 0x99"). Hashes data from the region [[IO_Registers|0x10012000-0x10012090]] using SHA256 via the [[SHA_Registers|SHA]] hardware.
* Clears bit6 in [[AES_Registers|REG_AESKEYCNT]]. Initializes AES keyslot 0x11 keyX, keyY to the lower and higher portion of the above hash, respectively. Due to the above hashed data, the keyX+keyY here are console-unique.
* Clears bit6 in [[AES_Registers|REG_AESKEYCNT]]. Initializes AES keyslot 0x11 keyX, keyY to the lower and higher portion of the above hash, respectively. Due to the above hashed data, the keyX+keyY here are console-unique.
* Decrypts the first 0x10-byte block in the above read NAND sector with keyslot 0x11 using AES-ECB. Then the normalkey, keyX, and keyY, for keyslot 0x11 are cleared to zero. Runs the TWL key-init/etc code which was originally in the ARM9-kernel, then writes 0x2 to [[CONFIG_Registers|REG_SYSPROT9]]. Then it uses the output block to set the normalkey for keyslot 0x11.
* Decrypts the first 0x10-byte block in the above read NAND sector with keyslot 0x11 using AES-ECB. [[9.6.0-24|9.6.0-X]]: Then it decrypts the 0x10-bytes at offset 0x10 in the sector with keyslot 0x11.
* Then the normalkey, keyX, and keyY, for keyslot 0x11 are cleared to zero. Runs the TWL key-init/etc code which was originally in the ARM9-kernel, then writes 0x2 to [[CONFIG_Registers|REG_SYSPROT9]].
* Initialises KeyX for keyslots 0x18..0x1F with the output of decrypting a 0x10-byte block with AES-ECB using keyslot 0x11. Before doing the crypto each time, the loader sets the normal-key for keyslot 0x11 to the same one already decrypted on the stack. This block sits 0xA0 before the end of the ARM9 binary, and has a SHA-256 of 219DA61289A1D8A85F403A8BC6EBA635269D72FE592EF97DED1D4F7BBDC789E6. The last byte in this 0x10-byte input block is increased by 0x01 after initializing each keyslot. These are New3DS-specific keys.
* Then it uses the above decrypted block from sector+0 to set the normalkey for keyslot 0x11. Decrypts arm9_bin_buf+0 using keyslot 0x11 with AES-ECB, and initialises keyX for keyslot 0x15 with it.
* [[9.5.0-22|9.5.0-X]]: Sets the normal-key for keyslot 0x11 to the same one already decrypted on the stack. Decrypts the 0x10-byte block at arm9binhdr+0x60 with AES-ECB using keyslot 0x11, then sets the keyX for keyslot 0x16 to the output data. The normalkey, keyX, and keyY, for keyslot 0x11 are cleared to zero.
* [[9.6.0-24|9.6.0-X]]: Then it uses the above decrypted block from sector+0 to set the normalkey for keyslot 0x11. Decrypts a 0x10-byte block from arm9loader .(ro)data using keyslot 0x11 with AES-ECB, and initializes keyX for keyslot 0x18 with it(same block as previous versions).
* [[9.6.0-24|9.6.0-X]]: Starting with this version keyslot 0x16 keyX init was moved here, see below for details on this. The code for this is same as [[9.5.0-22|9.5.0-X]], except the decrypted normalkey from sector+0x10 is used for keyslot 0x11 instead.
* Initialises KeyX for keyslots 0x18..0x1F(0x19..0x1F with [[9.6.0-24|9.6.0-X]]) with the output of decrypting a 0x10-byte block with AES-ECB using keyslot 0x11. This block was changed to a new one separate from keyslot 0x18, starting with [[9.6.0-24|9.6.0-X]]. Before doing the crypto each time, the loader sets the normal-key for keyslot 0x11 to the plaintext normalkey from sector+0(+0x10 with [[9.6.0-24|9.6.0-X]]). This block sits 0xA0 before the end of the ARM9 binary(pre-[[9.6.0-24|9.6.0-X]]), and has a SHA-256 of 219DA61289A1D8A85F403A8BC6EBA635269D72FE592EF97DED1D4F7BBDC789E6. The last byte in this 0x10-byte input block is increased by 0x01 after initializing each keyslot. These are New3DS-specific keys.
* [[9.5.0-22|9.5.0-X]](moved to above with [[9.6.0-24|9.6.0-X]]): Sets the normal-key for keyslot 0x11 to the same one already decrypted on the stack. Decrypts the 0x10-byte block at arm9binhdr+0x60 with AES-ECB using keyslot 0x11, then sets the keyX for keyslot 0x16 to the output data.
* [[9.5.0-22|9.5.0-X]]: The normalkey, keyX, and keyY, for keyslot 0x11 are then cleared to zero.
When (u8*)0x10000000 bit 1 is set(which means this happens only when this loader runs again for firm-launch), the normalkey, keyX, and keyY, for keyslot 0x11 are cleared to zero.
When (u8*)0x10000000 bit 1 is set(which means this happens only when this loader runs again for firm-launch), the normalkey, keyX, and keyY, for keyslot 0x11 are cleared to zero.