safe animation level

reverse-engineering/cimg-animate/DESCRIPTION.md

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+Okay, the previous level was embarrassing, but those sorts of bugs happen all the time!
+We fixed that issue in this level and, because we feel somewhat contrite about the bug, we're giving you the flag again... in an animated cIMG!
+Good luck.

reverse-engineering/cimg-animate/_0/generate_flag_cimg.py

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+#!/opt/pwn.college/python
+
+import subprocess
+import random
+import struct
+import os
+
+raw_flag_lines = subprocess.check_output("/usr/bin/figlet < /flag", shell=True).split(b"\n")
+max_line_length = max(len(line) for line in raw_flag_lines)
+flag_lines = [ line.ljust(max_line_length) for line in raw_flag_lines ]
+
+flag_pixels = [ ]
+for y,line in enumerate(flag_lines):
+	for x,c in enumerate(line):
+		flag_pixels += [ (x, y, c) ]
+random.shuffle(flag_pixels)
+
+operations = [ ]
+for p in flag_pixels:
+	operations += [ struct.pack("<HBBBBBBBB", 2, p[0], p[1], 1, 1, 0x8c, 0x1d, 0x40, p[2]) ]
+	operations += [ struct.pack("<HB", 6, 1) ]
+	operations += [ struct.pack("<HI", 7, 733_331) ]
+
+img = b"cIMG" + struct.pack("<HBBI", 4, max_line_length, len(flag_lines), len(operations)) + b"".join(operations)
+with open("/challenge/the_flag.cimg", "wb") as o:
+	o.write(img)