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AEA

How to extract from/mount these NEW .dmg.aea files​

  • It all works seemlessly in the background so you don't have to worry about it at all.
  • It will also work offline as the latest version of ipsw will always have the AEA private keys embedded.

What if I want to mess with them?​

Download AEA PEMs​

Download AEA PEMs from remote IPSWs

aea-dl-pem

You can also pull them out of local/remote IPSWs

❯ ipsw extract --fcs-key iPhone16,2_18.0_22A5307f_Restore.ipsw
   • Extracting AEA1 DMG fcs-keys
      • Created 22A5307f__iPhone16,2/090-29713-065.dmg.aea.pem
      • Created 22A5307f__iPhone16,2/090-27454-052.dmg.aea.pem

Now extract one of these pesky .dmg.aea files

❯ ipsw extract --dmg sys iPhone16,2_18.0_22A5307f_Restore.ipsw
   • Extracting DMG
        1.50 GiB / 1.50 GiB [====================================| ✅  ] 1.50 GiB/s
        229.00 b / 229.00 b [====================================| ✅  ]
        2.04 KiB / 2.04 KiB [====================================| ✅  ]
      • Created 22A5307f__iPhone16,2/090-29713-065.dmg.aea
      • Created 22A5307f__iPhone16,2/Firmware/090-29713-065.dmg.aea.root_hash
      • Created 22A5307f__iPhone16,2/Firmware/090-29713-065.dmg.aea.trustcache

Use an extracted PEM​

Use an extracted PEM file to decrypt a *.dmg.aea file

❯ ipsw fw aea --pem '22A5307f__iPhone16,2/090-29713-065.dmg.aea.pem'
                    '22A5307f__iPhone16,2/090-29713-065.dmg.aea' --output /tmp
   • Extracted AEA to /tmp/090-29713-065.dmg

Dump all the AEA metadata​

Dump all the AEA metadata from a local AEA file

This parses the AEA header and metadata and presents it for you in --color

aea-info

Extract the AEA Private Key​

Extract the AEA private key that you can use with the aea binary to decrypt the *.dmg.aea

❯ ipsw fw aea --key iPhone16,2_18.0_22A5282m_Restore/090-27454-036.dmg.aea

'base64:S8f/KZsKuRXg/RnkMlG6SWiFtSPlmwz9YFdBnyPc1EQ='

Decrypt with /usr/bin/aea

❯ aea decrypt -i iPhone16,2_18.0_22A5282m_Restore/090-27454-036.dmg.aea
      -o TEST.dmg -key-value 'base64:S8f/KZsKuRXg/RnkMlG6SWiFtSPlmwz9YFdBnyPc1EQ='

You can also use ipsw

❯ ipsw fw aea --key-val 'base64:S8f/KZsKuRXg/RnkMlG6SWiFtSPlmwz9YFdBnyPc1EQ='
                    '22A5307f__iPhone16,2/090-29713-065.dmg.aea' --output /tmp
                    
   • Extracted AEA to /tmp/090-29713-065.dmg

Download AEA PEMs as JSON "Database"​

Download AEA PEMs as JSON form remote IPSWs (using ipsw's patent pending partial-partialzip ™️)

aea-dl-jsondb

note

It appears that these AEA PEM keys are unique per release for iOS and macOS. (So only 2 🆕 keys per release; 1 iOS and 1 macOS)

OTA AEA keys are different - they're unique per file. See OTA AEA Keys for building an OTA-specific keys database.

To get the macOS PEM JSON "Database"

❯ ipsw dl appledb --os macOS --version '15.0 beta 2' --fcs-keys-json --output /tmp --confirm
   • Querying AppleDB...
   • Parsing remote IPSW       build=24A5279h devices=UniversalMac version=15.0
   • Extracting remote AEA1 DMG fcs-keys
      • Created '/tmp/fcs-keys.json'

You can also dump the PEM in the JSON database from a local file

❯ ipsw fw aea --fcs-key iPhone16,2_18.0_22A5282m_Restore/090-27454-036.dmg.aea
   • Created fcs-keys.json
{
  "C76OEoiX5Lfc0nRQtn1cLkOEwDtC8HGIM_M_1rJgQ9g=":"LS0tLS1CRUdJTiBQUklWQVRFIEtFWS0tLS0tCk1JR0hBZ0VBTUJNR0J5cUdTTTQ5QWdFR0NDcUdTTTQ5QXdFSEJHMHdhd0lCQVFRZ21qWDBwYmU2WWErMDJUek4KY0laWHZ6L1VId1lMN1JwUVFka01QV1pmT2UraFJBTkNBQVRzeUsxZEJzUFJVZU15b2hWM2VJUG5JNGw2SzhjUApWeGZGRXBEd01DdXNlTUVrV0UzV0w5QXcvTTMyRk5Ta2lYZUNpQXoxMXBOdUJVWGVmTkFPSXlkSQotLS0tLUVORCBQUklWQVRFIEtFWS0tLS0tCg=="
}
note

This "Database" is a key-value pair JSON file where the key is the unique part of the fcs-key-url as can been seen above in the --info dump from a .dmg.aea file AND the value of the key-value is the base64 encoded PEM bytes.

Use AEA PEM Database​

❯ ipsw mount fs --pem-db 'fcs-keys.json' iPhone16,2_18.0_22A5282m_Restore.ipsw
   • Mounted fs DMG 090-27454-036.dmg
      • Press Ctrl+C to unmount '/tmp/090-27454-036.dmg.mount' ...
note

This fcs-keys.json is what I'm refering to as an AEA PEM JSON Database and it can be used offline via the --pem-db flag on several ipsw commands. This allows you to just update the JSON Database instead of having to contantly download a 🆕 version of ipsw to use offline on latest *.dmg.aea files.

Sinkhole/Proxy Apple PEM Server​

You can use ipswd to also serve the fcs-keys.json DB by adding the following to the ~/.config/ipsw/config.yml

daemon:
  pem-db: /path/to/fcs-keys.json

Start the daemon

ipswd start

The daemon is now hosting the route GET /v1/aea/fcs-keys/:key

❯ http localhost:3993/v1/aea/fcs-keys/zhYs0f2L4kS-0oTUtvLn1JZdp4YGOoLbKFBad8ui7Vo=
HTTP/1.1 200 OK
Content-Length: 241
Content-Type: application/octet-stream
Date: Wed, 10 Jul 2024 23:33:15 GMT

-----BEGIN PRIVATE KEY-----
MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQgeHM016M8mfitwIag
gsNwsYLUrNgifqq5VRdR8USWAdGhRANCAATl3LnJS5y4HbGj72pGcKpka8WbocXi
2cVY4NlhgpH5VRFwPcWtHZnoWj0hxDqB5V+b14UkPXsyelZIP91MEO8T
-----END PRIVATE KEY-----

You can use the above ipsw dl appledb command periodically to update the fcs-keys.json (which appends) and transfer that file over to your offline system running ipswd to prevent needing to constantly update ipsw to latest etc.

Now you just need to proxy https://wkms-public.apple.com/fcs-keys to http://localhost:3993/v1/aea/fcs-keys

This works because ipsw will:

  1. Try it's embedded PEM keys
  2. Try the --pem-db you provided
  3. Try and reach out to Apple's server to get the PEM
    i) Which ipswd will happily serve to it (if you follow the above steps) 😎