Function at 0x41bf90
Capabilities:
Validate payment card number using luhn algorithm

Disassembly:
push ebx
push ebp
push esi
mov esi, dword [esp + 0x14]
mov al, byte [esi]
test al, al
push edi
je 0x41c32b
cmp al, 0x25
jne 0x41c311
push 3
add esi, 1
push 0x49aad4
push esi
call fcn.0048240a
add esp, 0xc
test eax, eax
jne 0x41c0d1
movsx eax, byte [esi + 3]
add esi, 3
sub eax, 0x25
add esi, 1
cmp eax, 0x4d
ja case.default.0x41c2b0
movzx eax, byte [eax + 0x41c34c]
jmp dword [eax*4 + 0x41c33c]
mov ecx, dword [esp + 0x1c]
mov al, byte [ecx + 1]
add ecx, 1
test al, al
je 0x41c321
mov edx, dword [esp + 0x14]
nop
add ecx, 1
mov byte [edx], al
mov al, byte [ecx]
add edx, 1
test al, al
jne 0x41c000
mov dword [esp + 0x14], edx
jmp 0x41c321
mov cl, byte [esi]
xor eax, eax
cmp cl, 0x30
jl 0x41c039
cmp cl, 0x39
jg 0x41c039
lea edx, [eax + eax*4]
add esi, 1
movsx eax, cl
mov cl, byte [esi]
cmp cl, 0x30
lea eax, [eax + edx*2 - 0x30]
jge 0x41c020
mov edx, dword [esp + 0x1c]
add edx, 1
test eax, eax
je 0x41c05f
mov edi, dword [esp + 0x14]
mov cl, byte [edx]
test cl, cl
je 0x41c05b
mov byte [edi], cl
add edi, 1
add edx, 1
sub eax, 1
jne 0x41c048
mov dword [esp + 0x14], edi
cmp byte [esi], 0x25
je 0x41c31e
pop edi
pop esi
pop ebp
xor al, al
pop ebx
ret
mov al, byte [esi]
xor edi, edi
cmp al, 0x30
jl 0x41c08e
cmp al, 0x39
jg 0x41c08e
add esi, 1
movsx edx, al
mov al, byte [esi]
cmp al, 0x30
lea ecx, [edi + edi*4]
lea edi, [edx + ecx*2 - 0x30]
jge 0x41c077
mov ebx, dword [esp + 0x1c]
lea eax, [ebx + 1]
push eax
call dword [sym.imp.KERNEL32.dll_lstrlenA]
cmp eax, edi
jge 0x41c0a2
mov edi, eax
sub eax, edi
test edi, edi
lea ecx, [eax + ebx + 1]
je 0x41c0c7
mov edx, dword [esp + 0x14]
mov al, byte [ecx]
test al, al
je 0x41c0c3
mov byte [edx], al
add edx, 1
add ecx, 1
sub edi, 1
jne 0x41c0b0
mov dword [esp + 0x14], edx
cmp byte [esi], 0x25
jne case.default.0x41c2b0
jmp 0x41c31e
mov al, byte [esi]
cmp al, 0x70
je 0x41c0db
cmp al, 0x50
jne case.default.0x41c2b0
movsx eax, byte [esi + 1]
add esi, 1
sub eax, 0x31
js case.default.0x41c2b0
cmp eax, 9
jg case.default.0x41c2b0
mov ecx, dword [esp + 0x1c]
mov ebp, dword [ecx + eax*4 + 0x48]
movsx eax, byte [esi + 1]
add esi, 1
sub eax, 0x25
add esi, 1
cmp eax, 0x50
ja case.default.0x41c2b0
movzx edx, byte [eax + 0x41c3ac]
jmp dword [edx*4 + 0x41c39c]
mov al, byte [esi]
xor ecx, ecx
cmp al, 0x30
jl 0x41c13b
cmp al, 0x39
jg 0x41c13b
add esi, 1
movsx edx, al
mov al, byte [esi]
cmp al, 0x30
lea ecx, [ecx + ecx*4]
lea ecx, [edx + ecx*2 - 0x30]
jge 0x41c124
lea eax, [ecx - 1]
cmp eax, 8
ja case.default.0x41c2b0
jmp dword [eax*4 + 0x41c400]
mov ecx, 0xa
jmp 0x41c18b
mov ecx, 0x64
jmp 0x41c18b
mov ecx, 0x3e8
jmp 0x41c18b
mov ecx, 0x2710
jmp 0x41c18b
mov ecx, 0x186a0
jmp 0x41c18b
mov ecx, 0xf4240
jmp 0x41c18b
mov ecx, 0x989680
jmp 0x41c18b
mov ecx, 0x5f5e100
jmp 0x41c18b
mov ecx, 0x3b9aca00
cmp ebp, ecx
jl 0x41c196
mov eax, ebp
cdq
idiv ecx
mov ebp, edx
mov eax, 0x66666667
imul ecx
sar edx, 2
mov ecx, edx
shr ecx, 0x1f
add ecx, edx
cmp byte [esi], 0x25
jne case.default.0x41c2b0
add esi, 1
test ecx, ecx
je 0x41c321
jmp 0x41c1c0
mov eax, ebp
cdq
idiv ecx
mov ebx, eax
mov eax, 0x66666667
imul ecx
sar edx, 2
mov eax, edx
shr eax, 0x1f
add bl, 0x30
add eax, edx
mov ecx, eax
jne 0x41c1c0
mov ecx, dword [esp + 0x14]
mov byte [ecx], bl
jmp 0x41c321
mov al, byte [esi]
xor ecx, ecx
cmp al, 0x30
jl 0x41c209
cmp al, 0x39
jg 0x41c209
add esi, 1
movsx edx, al
mov al, byte [esi]
cmp al, 0x30
lea ecx, [ecx + ecx*4]
lea ecx, [edx + ecx*2 - 0x30]
jge 0x41c1f2
lea eax, [ecx - 1]
cmp eax, 8
ja case.default.0x41c2b0
jmp dword [eax*4 + 0x41c424]
mov ecx, 0xa
jmp 0x41c259
mov ecx, 0x64
jmp 0x41c259
mov ecx, 0x3e8
jmp 0x41c259
mov ecx, 0x2710
jmp 0x41c259
mov ecx, 0x186a0
jmp 0x41c259
mov ecx, 0xf4240
jmp 0x41c259
mov ecx, 0x989680
jmp 0x41c259
mov ecx, 0x5f5e100
jmp 0x41c259
mov ecx, 0x3b9aca00
cmp ebp, ecx
jl 0x41c196
mov eax, 0x66666667
imul ebp
sar edx, 2
mov eax, edx
shr eax, 0x1f
add eax, edx
mov ebp, eax
cmp ebp, ecx
jge 0x41c261
jmp 0x41c196
test ebp, ebp
mov ecx, ebp
je 0x41c29f
xor edi, edi
mov eax, 0x66666667
imul ecx
sar edx, 2
mov ecx, edx
shr ecx, 0x1f
add ecx, edx
add edi, 1
test ecx, ecx
jne 0x41c285
jmp 0x41c2a4
mov edi, 1
lea eax, [edi - 1]
cmp eax, 8
ja case.default.0x41c2b0
jmp dword [eax*4 + 0x41c448]
mov ecx, 1
jmp 0x41c1c0
mov ecx, 0xa
jmp 0x41c1c0
mov ecx, 0x64
jmp 0x41c1c0
mov ecx, 0x3e8
jmp 0x41c1c0
mov ecx, 0x2710
jmp 0x41c1c0
mov ecx, 0x186a0
jmp 0x41c1c0
mov ecx, 0xf4240
jmp 0x41c1c0
mov ecx, 0x989680
jmp 0x41c1c0
mov ecx, 0x5f5e100
jmp 0x41c1c0
mov ecx, dword [esp + 0x14]
mov byte [ecx], al
add ecx, 1
mov dword [esp + 0x14], ecx
add esi, 1
mov al, byte [esi]
test al, al
jne 0x41bfa2
mov edx, dword [esp + 0x14]
pop edi
pop esi
pop ebp
mov byte [edx], 0
mov al, 1
pop ebx
ret