Mounting HDD in Linux

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Revision as of 00:28, 5 September 2020 by CelesteBlue (talk | contribs)
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Unlike PS3, where every part of per-console security (including the HDD) is dictated by the eid_root_key, PS4 has two per-console keys for the HDD, one handled by SAMU (we cannot obtain this key atm) and the other handled by the South Bridge (Aeolia / Belize) which can be obtained.

Here are described the steps to mount a PS4 HDD on PC using the cryptmount utility on Linux.

Setup

Prerequisites

  • Per-console PS4 EAP HDD Key (check in your kernel dump and in hxxps://github.com/Ps3itaTeam/ps4-kexec/blob/master/magic.h kern_off_eap_hdd_key offset)
  • A PC running a Linux Distribution (ex: ubuntu, xubuntu live) that supports cryptmount

Getting eap_hdd_key.bin

You have to put the eap_hdd_key.bin file anywhere you want according to the cmtab file (see cmtab section below).

From kernel dump

  • If your EAP HDD Key in the kernel dump looks like this:
D2 60 86 B3 8B D2 D3 5A EC 76 DB DE 50 30 00 40
15 D6 AE 04 44 3D A8 59 4B 03 3C 1F 0A DD FA 6B
  • then the correct key will be:
40 00 30 50 DE DB 76 EC 5A D3 D2 8B B3 86 60 D2
6B FA DD 0A 1F 3C 03 4B 59 A8 3D 44 04 AE D6 15

From sflash

The keys.bin produced by hdd_script.py v2 will produce the keys in the right order! Just use keys.bin as eap_hdd_key.bin

Installing cryptmount

sudo apt install cryptmount

Settuping cmtab

  • Add write permission on cmtab file:
sudo chmod 777 /dev/cryptmount/cmtab

cmtab for CUH-1000 and some CUH-1100

  • cmtab file can be as follows:
# /etc/cryptmount/cmtab - encrypted filesystem information for cryptmount
# try 'man 8 cryptmount' or 'man 5 cmtab' for more details
user {
    dev=/dev/sda27
    dir=/home/xubuntu/Desktop/user
    flags=user,nofsck
    fstype=ufs mountoptions=ro,noatime,noexec,ufstype=ufs2
    cipher=aes-xts-plain64
    keyfile=/home/eap_hdd_key.bin
    keyformat=raw
}

cmtab for some CUH-1100 and later models

  • In this case the cmtab file must have a small change:
# /etc/cryptmount/cmtab - encrypted filesystem information for cryptmount
# try 'man 8 cryptmount' or 'man 5 cmtab' for more details
user {
    dev=/dev/sda27
    dir=/home/username/Desktop/user
    flags=user,nofsck
    fstype=ufs mountoptions=ro,noatime,noexec,ufstype=ufs2
    cipher=aes-xts-plain64
    ivoffset=111669149696
    keyfile=/home/eap_hdd_key.bin
    keyformat=raw
}
  • where ivoffset = (dev_no - 1) << 32
  • here it is: (27 - 1) << 32 = 111669149696

Adapting cmtab

  • Change "username" to your Linux user name.
  • Change sda27 to sdb27 or sdc27, etc... according to where HDD is currently mounted.
  • Change sda27 to sda1 or sda2 or etc... according to the partition you want to mount. Don't forget to change ivoffset and fstype accordingly.

Final steps

  • Create "user" folder on Linux Desktop.
  • Remove write permission on cmtab file:
sudo chmod 775 /dev/cryptmount/cmtab
  • Mount PS4 "user" partition:
sudo cryptmount user

Sample cmtab

# /etc/cryptmount/cmtab - encrypted filesystem information for cryptmount
# try 'man 8 cryptmount' or 'man 5 cmtab' for more details

eap_vsh {
    dev=/dev/sda7
    dir=/home/username/Desktop/eap_vsh
    flags=user,nofsck
    fstype=msdos mountoptions=ro,noatime,noexec
    cipher=aes-xts-plain64
    ivoffset=25769803776
    keyfile=/home/eap_hdd_key.bin
    keyformat=raw
}

eap_user {
    dev=/dev/sda29
    dir=/home/username/Desktop/eap_user
    flags=user,nofsck
    fstype=ufs mountoptions=ro,noatime,noexec,ufstype=ufs2
    cipher=aes-xts-plain64
    ivoffset=120259084288
    keyfile=/home/eap_hdd_key.bin
    keyformat=raw
}

user {
    dev=/dev/sda27
    dir=/home/username/Desktop/user
    flags=user,nofsck
    fstype=ufs mountoptions=ro,noatime,noexec,ufstype=ufs2
    cipher=aes-xts-plain64
    ivoffset=111669149696
    keyfile=/home/eap_hdd_key.bin
    keyformat=raw
}