A2PR#6 (100)
programming - Virginia TSA Technosphere CTF
Challenge description:
A disk a day will keep the doctor away.
Download file: a2pr6.dsk
Solution
We can run the file command to get more information on the file.
$ file a2pr6.dsk
a2pr6.dsk: Apple ProDOS Image, Volume /SYSTEMSK, 280 Blocks
A Google search on working with ProDOS images revealed the tool AppleCommander. While I did not have success with the GUI versions, the CLI release, AppleCommander-acx-1.7.0.jar, was fine.
$ java -jar AppleCommander-acx-1.7.0.jar ls --disk=a2pr6.dsk
File: a2pr6.dsk
Name: /SYSTEM/
PRODOS SYS 034 09/19/2007 12/15/1991 16 509
TEST BAS 001 09/19/2007 09/19/2007 3 A=$0801
FINDER.DATA FND 001 12/13/2020 12/13/2020 107
BASIC.SYSTEM SYS 021 02/13/1992 04/10/1993 10,240 A=$2000
STARTUP BIN 001 01/30/2022 01/30/2022 38 A=$8000
FINDER.ROOT FND 001 12/13/2020 12/13/2020 9
ProDOS format; 109,568 bytes free; 33,792 bytes used.
$ java -jar AppleCommander-acx-1.7.0.jar x STARTUP --disk=CTF.dsk
Offset Hex Data Characters
======= ================================================ =================
$000000 20 58 FC A2 00 BD 11 80 F0 06 20 ED FD E8 10 F5 X|".=.. p. m}h.u
$000010 60 E6 EC E1 E7 FB E1 F0 F0 EC E5 E9 E9 E6 EF F2 `******* ********
$000020 E5 F6 E5 F2 FD 00 .. .. .. .. .. .. .. .. .. .. *****.
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