Function at 0x4287a9
Capabilities:
Encode data using xor

Disassembly:
push ebp
mov ebp, esp
push ecx
cmp dword [ebp + 8], 0
push esi
not eax
mov ecx, 0xff
je 0x4287d7
test dl, 3
je 0x4287d7
movzx esi, byte [edx]
xor esi, eax
and esi, ecx
shr eax, 8
xor eax, dword [esi*4 + 0x421260]
inc edx
dec dword [ebp + 8]
jne 0x4287bb
cmp dword [ebp + 8], 0x20
push ebx
push edi
push 4
mov esi, edx
pop edi
jb 0x4289a6
mov edx, dword [ebp + 8]
shr edx, 5
mov dword [ebp - 4], edx
xor eax, dword [esi]
add esi, edi
mov edx, eax
shr edx, 0x10
mov ebx, eax
shr ebx, 8
and edx, ecx
mov edx, dword [edx*4 + 0x421660]
and ebx, ecx
xor edx, dword [ebx*4 + 0x421a60]
mov ebx, eax
shr ebx, 0x18
xor edx, dword [ebx*4 + 0x421260]
and eax, ecx
xor edx, dword [eax*4 + 0x421e60]
xor edx, dword [esi]
add esi, edi
mov eax, edx
shr eax, 0x10
mov ebx, edx
shr ebx, 8
and eax, ecx
mov eax, dword [eax*4 + 0x421660]
and ebx, ecx
xor eax, dword [ebx*4 + 0x421a60]
mov ebx, edx
shr ebx, 0x18
xor eax, dword [ebx*4 + 0x421260]
and edx, ecx
xor eax, dword [edx*4 + 0x421e60]
xor eax, dword [esi]
add esi, edi
mov edx, eax
shr edx, 0x10
mov ebx, eax
and edx, ecx
mov edx, dword [edx*4 + 0x421660]
shr ebx, 8
and ebx, ecx
xor edx, dword [ebx*4 + 0x421a60]
mov ebx, eax
shr ebx, 0x18
xor edx, dword [ebx*4 + 0x421260]
and eax, ecx
xor edx, dword [eax*4 + 0x421e60]
xor edx, dword [esi]
add esi, edi
mov eax, edx
shr eax, 0x10
mov ebx, edx
shr ebx, 8
and eax, ecx
mov eax, dword [eax*4 + 0x421660]
and ebx, ecx
xor eax, dword [ebx*4 + 0x421a60]
mov ebx, edx
shr ebx, 0x18
xor eax, dword [ebx*4 + 0x421260]
and edx, ecx
xor eax, dword [edx*4 + 0x421e60]
xor eax, dword [esi]
add esi, edi
mov edx, eax
shr edx, 0x10
mov ebx, eax
and edx, ecx
mov edx, dword [edx*4 + 0x421660]
shr ebx, 8
and ebx, ecx
xor edx, dword [ebx*4 + 0x421a60]
mov ebx, eax
shr ebx, 0x18
xor edx, dword [ebx*4 + 0x421260]
and eax, ecx
xor edx, dword [eax*4 + 0x421e60]
xor edx, dword [esi]
add esi, edi
mov eax, edx
shr eax, 0x10
and eax, ecx
mov ebx, edx
mov eax, dword [eax*4 + 0x421660]
shr ebx, 8
and ebx, ecx
xor eax, dword [ebx*4 + 0x421a60]
mov ebx, edx
shr ebx, 0x18
xor eax, dword [ebx*4 + 0x421260]
and edx, ecx
xor eax, dword [edx*4 + 0x421e60]
sub dword [ebp + 8], 0x20
xor eax, dword [esi]
add esi, edi
mov edx, eax
mov ebx, eax
shr edx, 0x10
shr ebx, 8
and edx, ecx
mov edx, dword [edx*4 + 0x421660]
and ebx, ecx
xor edx, dword [ebx*4 + 0x421a60]
mov ebx, eax
shr ebx, 0x18
xor edx, dword [ebx*4 + 0x421260]
and eax, ecx
xor edx, dword [eax*4 + 0x421e60]
xor edx, dword [esi]
add esi, edi
mov eax, edx
shr eax, 0x10
and eax, ecx
mov eax, dword [eax*4 + 0x421660]
mov ebx, edx
shr ebx, 8
and ebx, ecx
xor eax, dword [ebx*4 + 0x421a60]
mov ebx, edx
shr ebx, 0x18
xor eax, dword [ebx*4 + 0x421260]
and edx, ecx
xor eax, dword [edx*4 + 0x421e60]
dec dword [ebp - 4]
jne 0x4287f1
cmp dword [ebp + 8], edi
jb 0x4289f3
mov edx, dword [ebp + 8]
shr edx, 2
mov dword [ebp - 4], edx
xor eax, dword [esi]
sub dword [ebp + 8], edi
mov edx, eax
shr edx, 0x10
and edx, ecx
mov edx, dword [edx*4 + 0x421660]
mov ebx, eax
shr ebx, 8
and ebx, ecx
xor edx, dword [ebx*4 + 0x421a60]
mov ebx, eax
shr ebx, 0x18
xor edx, dword [ebx*4 + 0x421260]
and eax, ecx
xor edx, dword [eax*4 + 0x421e60]
add esi, edi
dec dword [ebp - 4]
mov eax, edx
jne 0x4289b4
cmp dword [ebp + 8], 0
pop edi
pop ebx
je 0x428a12
movzx edx, byte [esi]
xor edx, eax
and edx, ecx
shr eax, 8
xor eax, dword [edx*4 + 0x421260]
inc esi
dec dword [ebp + 8]
jne 0x4289fb
not eax
pop esi
leave
ret