Function at 0x4027be
Capabilities:
Encode data using xor
Hash data with crc32

Disassembly:
push ebx
push ebp
push esi
mov esi, dword [esp + 0x10]
mov ebx, ecx
not ebx
mov ebp, 0xff
test esi, esi
je 0x4027ec
test dl, 3
je 0x4027ec
movzx eax, byte [edx]
xor eax, ebx
shr ebx, 8
and eax, ebp
xor ebx, dword [eax*4 + 0x423660]
inc edx
dec esi
jne 0x4027d2
push edi
cmp esi, 0x20
jb 0x4029eb
mov ebp, esi
mov edi, 0xff
shr ebp, 5
xor ebx, dword [edx]
add edx, 4
mov ecx, ebx
mov dword [esp + 0x14], edx
shr ecx, 0x10
mov eax, ebx
shr eax, 8
and ecx, edi
and eax, edi
mov edi, dword [esp + 0x14]
mov edx, dword [ecx*4 + 0x423a60]
xor edx, dword [eax*4 + 0x423e60]
mov eax, ebx
shr eax, 0x18
xor edx, dword [eax*4 + 0x423660]
movzx eax, bl
mov ebx, 0xff
xor edx, dword [eax*4 + 0x424260]
xor edx, dword [edi]
mov ecx, edx
mov eax, edx
shr eax, 8
and eax, ebx
shr ecx, 0x10
and ecx, ebx
mov ebx, dword [ecx*4 + 0x423a60]
xor ebx, dword [eax*4 + 0x423e60]
mov eax, edx
shr eax, 0x18
xor ebx, dword [eax*4 + 0x423660]
movzx eax, dl
mov edx, 0xff
xor ebx, dword [eax*4 + 0x424260]
xor ebx, dword [edi + 4]
mov ecx, ebx
mov eax, ebx
shr eax, 8
and eax, edx
shr ecx, 0x10
and ecx, edx
mov edx, dword [ecx*4 + 0x423a60]
xor edx, dword [eax*4 + 0x423e60]
mov eax, ebx
shr eax, 0x18
xor edx, dword [eax*4 + 0x423660]
movzx eax, bl
mov ebx, 0xff
xor edx, dword [eax*4 + 0x424260]
xor edx, dword [edi + 8]
mov ecx, edx
mov eax, edx
shr eax, 8
and eax, ebx
shr ecx, 0x10
and ecx, ebx
mov ebx, dword [ecx*4 + 0x423a60]
xor ebx, dword [eax*4 + 0x423e60]
mov eax, edx
shr eax, 0x18
xor ebx, dword [eax*4 + 0x423660]
movzx eax, dl
mov edx, 0xff
xor ebx, dword [eax*4 + 0x424260]
xor ebx, dword [edi + 0xc]
mov ecx, ebx
mov eax, ebx
shr ecx, 0x10
and ecx, edx
shr eax, 8
and eax, edx
mov edx, dword [ecx*4 + 0x423a60]
xor edx, dword [eax*4 + 0x423e60]
mov eax, ebx
shr eax, 0x18
xor edx, dword [eax*4 + 0x423660]
movzx eax, bl
mov ebx, 0xff
xor edx, dword [eax*4 + 0x424260]
xor edx, dword [edi + 0x10]
mov ecx, edx
shr ecx, 0x10
and ecx, ebx
mov eax, edx
shr eax, 8
sub esi, 0x20
and eax, ebx
mov ebx, dword [ecx*4 + 0x423a60]
xor ebx, dword [eax*4 + 0x423e60]
mov eax, edx
shr eax, 0x18
xor ebx, dword [eax*4 + 0x423660]
movzx eax, dl
mov edx, 0xff
xor ebx, dword [eax*4 + 0x424260]
xor ebx, dword [edi + 0x14]
mov ecx, ebx
mov eax, ebx
shr eax, 8
and eax, edx
shr ecx, 0x10
and ecx, edx
mov edx, dword [ecx*4 + 0x423a60]
xor edx, dword [eax*4 + 0x423e60]
mov eax, ebx
shr eax, 0x18
xor edx, dword [eax*4 + 0x423660]
movzx eax, bl
xor edx, dword [eax*4 + 0x424260]
xor edx, dword [edi + 0x18]
add edi, 0x1c
mov ecx, edx
mov dword [esp + 0x14], edi
shr ecx, 0x10
mov edi, 0xff
mov eax, edx
and ecx, edi
shr eax, 8
and eax, edi
mov ebx, dword [ecx*4 + 0x423a60]
xor ebx, dword [eax*4 + 0x423e60]
mov eax, edx
shr eax, 0x18
xor ebx, dword [eax*4 + 0x423660]
movzx eax, dl
mov edx, dword [esp + 0x14]
xor ebx, dword [eax*4 + 0x424260]
dec ebp
jne 0x402800
mov ebp, edi
cmp esi, 4
jb 0x402a34
mov edi, esi
shr edi, 2
xor ebx, dword [edx]
sub esi, 4
mov ecx, ebx
mov eax, ebx
shr ecx, 0x10
add edx, 4
and ecx, ebp
shr eax, 8
and eax, ebp
mov ecx, dword [ecx*4 + 0x423a60]
xor ecx, dword [eax*4 + 0x423e60]
mov eax, ebx
shr eax, 0x18
xor ecx, dword [eax*4 + 0x423660]
movzx eax, bl
xor ecx, dword [eax*4 + 0x424260]
mov ebx, ecx
dec edi
jne 0x4029f5
pop edi
test esi, esi
je 0x402a4e
movzx eax, byte [edx]
xor eax, ebx
shr ebx, 8
and eax, ebp
xor ebx, dword [eax*4 + 0x423660]
inc edx
dec esi
jne 0x402a39
pop esi
not ebx
pop ebp
mov eax, ebx
pop ebx
ret 4