1
edit
Changes
Add information about "impossible" consoles with uninitialized movable.sed files. See github issue for context.
The keyY is hashed with SHA256, the first 0x10-bytes from the hash is used with the below snprintf for ID0 in [[SD Filesystem|sdmc/Nintendo 3DS/<ID0>/<ID1>]] and [[Flash Filesystem|nand/data/<ID0>]]. ID0 is generated by: snprintf(outdirname, maxlen, "%08x%08x%08x%08x", hashword[0], hashword[1], hashword[2], hashword[3]). Thus, ID0 is the first half of the SHA-256 of movable.sed bytes 0x110-0x11F inclusive, with the four u32s of the half-SHA-256 byte-flipped.
The keyY is hashed with SHA256, the first 0x10-bytes from the hash is used with the below snprintf for ID0 in [[SD Filesystem|sdmc/Nintendo 3DS/<ID0>/<ID1>]] and [[Flash Filesystem|nand/data/<ID0>]]. ID0 is generated by: snprintf(outdirname, maxlen, "%08x%08x%08x%08x", hashword[0], hashword[1], hashword[2], hashword[3]). Thus, ID0 is the first half of the SHA-256 of movable.sed bytes 0x110-0x11F inclusive, with the four u32s of the half-SHA-256 byte-flipped.
'''Note:''' It has been observed at least 2 times that the 0x120+ part has been left uninitialized, yet the 3DS is still working without any form of modfication, behaving just as if it was initialized and working just fine with Custom Firmware installed.
It is currently unknown why this is the case, but the following information holds true for both systems:
* They are Old 3DS Retail Consoles from Europe
* They were shipped with Firmware version 1.0.0-0E
* Their Serial Number starts with CEM10, differ from there on
* SoC manufacturing date of 2010
* They have not been formatted, ever
More details [https://github.com/d0k3/GodMode9/issues/318 on this Github Issue]