I’m sweeping some old bitcoin wallets and I have two files named
- “Bitcoin Wallet backup” from 2020
- “bitcoin-wallet” from 2013
I’ve successfully recovered the first backup file by restoring it in Bitcoin Wallet (Android) using an Android emulator. I could have also recovered it using the bitcoinj CLI tools described in this recovery guide, and have since learned it was in the bitcoinj protobuf format.
I thought the second file might be the older BASE58 format, also described in the recovery guide, but it’s another binary format. Neither Bitcoin Core, Electrum, or Bitcoin Wallet (Android) understands the file and they all error when I try to open or restore it.
Digging inside the file reveals some ASCII text like main, which is presumably the wallet name, and 278 instances of ckey!, which this answer suggests are encrypted private keys.
~/Downloads % xxd bitcoin-wallet-2013-12-07 | head -4
00000000: 0000 0000 0100 0000 0000 0000 6231 0500 ............b1..
00000010: 0900 0000 0010 0000 0009 0000 0000 0000 ................
00000020: 0c00 0000 0000 0000 0000 0000 0000 0000 ................
00000030: 2000 0000 f703 8a00 0608 0000 010e 0ca9 ...............
~/Downloads % xxd bitcoin-wallet-2013-12-07 | grep main
00001ff0: 0400 0100 0000 0200 0400 016d 6169 6e00 ...........main.
~/Downloads % xxd bitcoin-wallet-2013-12-07 | grep -c ckey
278
Can anyone tell me what format this file might be? And if it’s possible to decrypt or inspect the private keys? I’ll update if I learn any more. Thanks!
