Function at 0x140281250
Capabilities:
Encode data using xor
Manually build aes constants

Disassembly:
mov qword [rsp + 8], rbx
mov qword [rsp + 0x10], rbp
mov qword [rsp + 0x18], rsi
mov qword [rsp + 0x20], rdi
push r12
push r14
push r15
sub rsp, 0x810
mov rax, qword [0x14048a080]
xor rax, rsp
mov qword [rsp + 0x800], rax
mov r10d, 1
lea r11, [rsp + 0x400]
mov r8d, r10d
xor r9d, r9d
mov ebx, 0x100
nop dword [rax]
mov eax, r8d
movzx ecx, r8b
mov dword [r11], r8d
lea r11, [r11 + 4]
and r8b, 0x80
mov dword [rsp + rax*4], r9d
movzx eax, cl
add al, al
movzx edx, al
xor edx, ecx
neg r8b
mov r8d, edx
sbb eax, eax
inc r9d
and eax, 0x1b
xor r8d, eax
cmp r9d, ebx
jl 0x1402812a0
mov edx, r10d
lea r8, [0x140c5a830]
mov r9d, 0xa
nop word [rax + rax]
mov eax, edx
mov dword [r8], edx
and al, 0x80
lea r8, [r8 + 4]
neg al
sbb ecx, ecx
add dl, dl
and ecx, 0x1b
movzx eax, dl
mov edx, ecx
xor edx, eax
sub r9, r10
jne 0x1402812f0
mov byte [0x140c59793], r9b
lea r11, [rsp + 4]
lea r9, [0x140c58631]
mov byte [0x140c58630], 0x63
lea r12, [0x140000000]
nop dword [rax]
nop word [rax + rax]
mov eax, 0xff
lea r9, [r9 + 1]
sub eax, dword [r11]
lea r11, [r11 + 4]
cdqe
mov r8d, dword [rsp + rax*4 + 0x400]
mov ecx, r8d
sar ecx, 7
lea eax, [r8 + r8]
or ecx, eax
movzx edx, cl
movzx eax, dl
xor r8d, edx
add al, al
shr edx, 7
movzx ecx, al
or ecx, edx
movzx eax, cl
xor r8d, ecx
add al, al
shr ecx, 7
movzx edx, al
or edx, ecx
movzx eax, dl
add al, al
movzx ecx, al
mov eax, edx
shr eax, 7
or ecx, eax
xor ecx, 0x63
xor ecx, edx
xor r8d, ecx
movsxd rax, r8d
mov byte [r9 - 1], r8b
mov byte [rax + r12 + 0xc59730], r10b
inc r10d
cmp r10d, ebx
jl 0x140281340
mov rsi, qword [rsp + 0x38]
xor r10d, r10d
mov rbp, qword [rsp + 0x34]
mov r14, qword [rsp + 0x2c]
mov r15, qword [rsp + 0x24]
nop
movzx r8d, byte [r10 + r12 + 0xc58630]
mov eax, r8d
and al, 0x80
neg al
movzx eax, r8b
sbb edx, edx
add al, al
movzx ecx, al
and edx, 0x1b
xor edx, ecx
mov eax, edx
xor eax, r8d
shl eax, 8
xor eax, r8d
shl eax, 8
xor eax, r8d
shl eax, 8
xor eax, edx
mov ecx, eax
mov dword [r12 + r10*4 + 0xc58730], eax
shl eax, 8
shr ecx, 0x18
or ecx, eax
mov eax, ecx
mov dword [r12 + r10*4 + 0xc58b30], ecx
shr eax, 0x18
shl ecx, 8
or eax, ecx
mov dword [r12 + r10*4 + 0xc58f30], eax
ror eax, 0x18
mov dword [r12 + r10*4 + 0xc59330], eax
movzx eax, byte [r10 + r12 + 0xc59730]
test al, al
je 0x14028150c
mov ecx, dword [rsp + rax*4]
mov r9d, eax
add ecx, r14d
mov eax, 0x80808081
imul ecx
mov r8d, dword [rsp + r9*4]
add edx, ecx
add r8d, ebp
sar edx, 7
mov eax, edx
shr eax, 0x1f
add edx, eax
imul eax, edx, 0xff
sub ecx, eax
mov eax, 0x80808081
imul r8d
movsxd rcx, ecx
add edx, r8d
sar edx, 7
mov eax, edx
mov ecx, dword [rsp + rcx*4 + 0x400]
shr eax, 0x1f
add edx, eax
imul eax, edx, 0xff
sub r8d, eax
movsxd rax, r8d
mov r8d, dword [rsp + r9*4]
add r8d, r15d
mov r11d, dword [rsp + rax*4 + 0x400]
mov eax, 0x80808081
imul r8d
add edx, r8d
sar edx, 7
mov eax, edx
shr eax, 0x1f
add edx, eax
imul eax, edx, 0xff
sub r8d, eax
movsxd rax, r8d
mov r8d, dword [rsp + r9*4]
add r8d, esi
mov edi, dword [rsp + rax*4 + 0x400]
mov eax, 0x80808081
imul r8d
add edx, r8d
sar edx, 7
mov eax, edx
shr eax, 0x1f
add edx, eax
imul eax, edx, 0xff
sub r8d, eax
movsxd rax, r8d
mov edx, dword [rsp + rax*4 + 0x400]
jmp 0x140281515
xor ecx, ecx
xor r11d, r11d
xor edi, edi
xor edx, edx
shl ecx, 8
xor ecx, r11d
shl ecx, 8
xor ecx, edi
shl ecx, 8
xor ecx, edx
mov edx, ecx
mov dword [r12 + r10*4 + 0xc59830], ecx
shr edx, 0x18
shl ecx, 8
or edx, ecx
mov eax, edx
mov dword [r12 + r10*4 + 0xc59c30], edx
shr eax, 0x18
shl edx, 8
or eax, edx
mov dword [r12 + r10*4 + 0xc5a030], eax
ror eax, 0x18
mov dword [r12 + r10*4 + 0xc5a430], eax
inc r10
sub rbx, 1
jne 0x1402813d0
mov rcx, qword [rsp + 0x800]
xor rcx, rsp
call fcn.14028bc70
lea r11, [rsp + 0x810]
mov rbx, qword [r11 + 0x20]
mov rbp, qword [r11 + 0x28]
mov rsi, qword [r11 + 0x30]
mov rdi, qword [r11 + 0x38]
mov rsp, r11
pop r15
pop r14
pop r12
ret