Function at 0x4201d8
Capabilities:
Encode data using xor
Hash data with crc32

Disassembly:
push ebx
push esi
push edi
mov edi, eax
shr edi, 8
mov esi, eax
shr esi, 0x18
and edi, 0xff00
add esi, edi
mov edi, eax
and edi, 0xff00
and eax, 0xff
shl edi, 8
push ebp
shl eax, 0x18
add esi, edi
add esi, eax
mov ebx, 0x427258
mov eax, esi
not eax
jmp 0x42022c
movzx edi, byte [edx]
mov esi, eax
inc edx
shr esi, 0x18
xor esi, edi
lea edi, [ebx + 0x1000]
shl eax, 8
mov esi, dword [edi + esi*4]
xor esi, eax
dec ecx
mov eax, esi
test ecx, ecx
je 0x420235
test dl, 3
jne 0x420210
sub edx, 4
cmp ecx, 0x20
jb 0x4204bd
add edx, 4
lea edi, [ebx + 0x1000]
lea ebp, [ebx + 0x1400]
sub ecx, 0x20
xor eax, dword [edx]
add edx, 4
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
lea ebp, [ebx + 0x1400]
xor esi, dword [edi + eax*4]
lea edi, [ebx + 0x1000]
mov eax, esi
xor eax, dword [edx]
add edx, 4
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
lea ebp, [ebx + 0x1400]
xor esi, dword [edi + eax*4]
lea edi, [ebx + 0x1000]
mov eax, esi
xor eax, dword [edx]
add edx, 4
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
lea ebp, [ebx + 0x1400]
xor esi, dword [edi + eax*4]
lea edi, [ebx + 0x1000]
mov eax, esi
xor eax, dword [edx]
add edx, 4
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
lea ebp, [ebx + 0x1400]
xor esi, dword [edi + eax*4]
lea edi, [ebx + 0x1000]
mov eax, esi
xor eax, dword [edx]
add edx, 4
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
lea ebp, [ebx + 0x1400]
xor esi, dword [edi + eax*4]
lea edi, [ebx + 0x1000]
mov eax, esi
xor eax, dword [edx]
add edx, 4
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
lea ebp, [ebx + 0x1400]
xor esi, dword [edi + eax*4]
lea edi, [ebx + 0x1000]
mov eax, esi
xor eax, dword [edx]
add edx, 4
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
lea ebp, [ebx + 0x1400]
xor esi, dword [edi + eax*4]
lea edi, [ebx + 0x1000]
mov eax, esi
xor eax, dword [edx]
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
xor esi, dword [edi + eax*4]
cmp ecx, 0x20
mov eax, esi
jae 0x420241
cmp ecx, 4
jb 0x420518
add edx, 4
lea edi, [ebx + 0x1000]
lea ebp, [ebx + 0x1400]
sub ecx, 4
xor eax, dword [edx]
mov esi, eax
and esi, 0xff
mov esi, dword [edi + esi*4]
mov edi, eax
shr edi, 8
and edi, 0xff
xor esi, dword [ebp + edi*4]
mov edi, eax
shr edi, 0x10
lea ebp, [ebx + 0x1800]
and edi, 0xff
shr eax, 0x18
xor esi, dword [ebp + edi*4]
lea edi, [ebx + 0x1c00]
xor esi, dword [edi + eax*4]
cmp ecx, 4
mov eax, esi
jae 0x4204c2
add edx, 4
test ecx, ecx
je 0x42053d
movzx edi, byte [edx]
mov esi, eax
inc edx
shr esi, 0x18
xor esi, edi
lea edi, [ebx + 0x1000]
shl eax, 8
mov esi, dword [edi + esi*4]
xor esi, eax
dec ecx
mov eax, esi
jne 0x42051f
not eax
mov ecx, eax
mov edx, eax
shr ecx, 8
shr edx, 0x18
and ecx, 0xff00
add edx, ecx
mov ecx, eax
and ecx, 0xff00
and eax, 0xff
shl ecx, 8
shl eax, 0x18
add edx, ecx
add edx, eax
mov eax, edx
pop ebp
pop edi
pop esi
pop ebx
ret