Function at 0x100025b4c
Capabilities:
Encode data using xor
Get file size
Read file via mapping

Disassembly:
mov rax, rsp
mov qword [rax + 8], rcx
push rbp
push rsi
push rdi
push r12
push r13
push r14
push r15
sub rsp, 0x60
mov qword [rsp + 0x50], 0xfffffffffffffffe
mov qword [rax + 0x10], rbx
mov rdi, rdx
mov rbp, rcx
xor r13d, r13d
mov dword [rax + 0x18], r13d
mov ebx, r13d
mov r12d, r13d
lea rcx, [0x100083100]
mov rax, qword [0x100083100]
call qword [rax + 0x18]
add rax, 0x18
mov qword [rbp], rax
mov dword [rsp + 0xb0], 1
mov rcx, rbp
call fcn.1000202e8
mov qword [rsp + 0x30], r13
mov dword [rsp + 0x28], r13d
mov dword [rsp + 0x20], 3
xor r9d, r9d
mov edx, 0x80000000
lea r8d, [r13 + 1]
mov rcx, qword [rdi]
call qword [sym.imp.KERNEL32.dll_CreateFileW]
mov rdi, rax
mov qword [rsp + 0x40], rax
cmp rax, 0xffffffffffffffff
je 0x100025f8d
xor edx, edx
mov rcx, rax
call qword [sym.imp.KERNEL32.dll_GetFileSize]
mov esi, eax
cmp eax, 0xffffffff
je 0x100025f84
mov qword [rsp + 0x28], r13
mov dword [rsp + 0x20], esi
xor r9d, r9d
xor edx, edx
lea r8d, [r13 + 2]
mov rcx, rdi
call qword [sym.imp.KERNEL32.dll_CreateFileMappingW]
mov qword [rsp + 0x48], rax
cmp rax, r13
je 0x100025f84
mov qword [rsp + 0x20], rsi
xor r9d, r9d
xor r8d, r8d
lea edx, [r13 + 4]
mov rcx, rax
call qword [sym.imp.KERNEL32.dll_MapViewOfFile]
mov r14, rax
xor r9d, r9d
cmp rax, r9
je 0x100025f79
mov r15, rax
movzx r13d, word [rax]
mov ecx, r13d
cmp r13d, 0xbbef
je 0x100025c88
cmp ecx, 0xfeff
je 0x100025c7c
cmp ecx, 0xfffe
jne 0x100025ca5
mov ebx, esi
shr ebx, 1
sub ebx, 1
jmp 0x100025d47
mov ebx, esi
shr ebx, 1
sub ebx, 1
jmp 0x100025d47
cmp esi, 2
jbe 0x100025ca5
cmp byte [rax + 2], 0xbf
jne 0x100025ca5
mov r12d, 0xfde9
lea r15, [rax + 3]
add esi, 0xfffffffd
jmp 0x100025e11
or dword [rsp + 0xb8], 0xffffffff
lea r8, [rsp + 0xb8]
mov edx, esi
mov rcx, rax
call qword [sym.imp.ADVAPI32.dll_IsTextUnicode]
mov r11d, eax
xor r9d, r9d
cmp eax, r9d
je 0x100025cd1
mov ebx, esi
shr ebx, 1
jmp 0x100025d3e
mov r8d, 1
mov eax, r9d
mov edx, r9d
cmp esi, r9d
jle 0x100025d3b
mov rdi, r14
mov r10b, 0x80
or r12d, 0xffffffff
mov cl, byte [rdi]
test r10b, cl
cmovne r8d, r9d
cmp eax, r9d
jne 0x100025d10
cmp cl, r10b
jb 0x100025d1b
add cl, cl
add eax, 1
test r10b, cl
jne 0x100025cff
add eax, r12d
je 0x100025d3b
jmp 0x100025d1b
and cl, 0xc0
cmp cl, r10b
jne 0x100025d3b
add eax, r12d
add edx, 1
add rdi, 1
cmp edx, esi
jl 0x100025cec
cmp eax, r9d
ja 0x100025d3b
cmp r8d, r9d
jne 0x100025d3b
mov r12d, 0xfde9
jmp 0x100025e11
mov r12d, r9d
cmp r11d, r9d
je 0x100025e11
lea esi, [rbx + 1]
mov rax, qword [rbp]
mov ecx, 1
sub ecx, dword [rax - 8]
mov eax, dword [rax - 0xc]
sub eax, esi
or eax, ecx
jge 0x100025d69
mov edx, esi
mov rcx, rbp
call fcn.100020154
mov rdi, qword [rbp]
xor r12d, r12d
cmp esi, r12d
jl 0x100025e06
cmp esi, dword [rdi - 0xc]
jg 0x100025e06
mov dword [rdi - 0x10], esi
movsxd rcx, esi
mov rax, qword [rbp]
mov word [rax + rcx*2], r12w
cmp r13w, 0xfeff
jne 0x100025db0
mov r8d, ebx
add r8, r8
lea rdx, [r14 + 2]
mov rcx, rdi
call sub.msvcrt.dll_memcpy
jmp 0x100025eee
cmp r13w, 0xfffe
jne 0x100025df0
lea rdx, [r14 + 2]
cmp ebx, r12d
jbe 0x100025eee
mov r8, rdi
sub r8, rdx
mov r9d, ebx
movzx ecx, byte [rdx + 1]
movzx eax, word [rdx]
shl ax, 8
xor cx, ax
mov word [r8 + rdx], cx
add rdx, 2
sub r9, 1
jne 0x100025dce
jmp 0x100025eee
mov r8d, ebx
add r8, r8
mov rdx, r14
mov rcx, rdi
call sub.msvcrt.dll_memcpy
jmp 0x100025eee
mov ecx, 0x80070057
call fcn.1000201f8
int3
mov dword [rsp + 0x28], r9d
mov qword [rsp + 0x20], r9
mov r9d, esi
mov r8, r15
xor edx, edx
mov ecx, r12d
call qword [sym.imp.KERNEL32.dll_MultiByteToWideChar]
mov ebx, eax
test eax, eax
je 0x100025f6b
lea r13d, [rax + 1]
mov rcx, qword [rbp]
mov edx, 1
sub edx, dword [rcx - 8]
mov ecx, dword [rcx - 0xc]
sub ecx, r13d
or ecx, edx
jge 0x100025e5b
mov edx, r13d
mov rcx, rbp
call fcn.100020154
mov rdi, qword [rbp]
test r13d, r13d
js 0x100025f60
cmp r13d, dword [rdi - 0xc]
jg 0x100025f60
mov dword [rdi - 0x10], r13d
movsxd rdx, r13d
mov rax, qword [rbp]
and word [rax + rdx*2], 0
mov dword [rsp + 0x28], ebx
mov qword [rsp + 0x20], rdi
mov r9d, esi
mov r8, r15
xor edx, edx
mov ecx, r12d
call qword [sym.imp.KERNEL32.dll_MultiByteToWideChar]
xor r12d, r12d
cmp eax, r12d
jne 0x100025eee
mov rdx, qword [rbp]
cmp rdx, r12
jne 0x100025eb2
mov ecx, r12d
jmp 0x100025eca
xor eax, eax
or rcx, 0xffffffffffffffff
mov rdi, rdx
repne scasw ax, word [rdi]
not rcx
sub rcx, 1
cmp ecx, r12d
jl 0x100025ee3
cmp ecx, dword [rdx - 0xc]
jg 0x100025ee3
mov dword [rdx - 0x10], ecx
movsxd rcx, ecx
mov rax, qword [rbp]
mov word [rax + rcx*2], r12w
jmp 0x100025f6b
mov ecx, 0x80070057
call fcn.1000201f8
int3
cmp rdi, r12
je 0x100025f6b
mov rax, rdi
cmp ebx, r12d
jbe 0x100025f12
mov ecx, ebx
cmp word [rax], r12w
jne 0x100025f08
mov word [rax], 0x20
add rax, 2
sub rcx, 1
jne 0x100025efd
mov eax, ebx
mov word [rdi + rax*2], r12w
mov rdx, qword [rbp]
cmp rdx, r12
jne 0x100025f27
mov ecx, r12d
jmp 0x100025f3f
xor eax, eax
or rcx, 0xffffffffffffffff
mov rdi, rdx
repne scasw ax, word [rdi]
not rcx
sub rcx, 1
cmp ecx, r12d
jl 0x100025f55
cmp ecx, dword [rdx - 0xc]
jg 0x100025f55
mov dword [rdx - 0x10], ecx
movsxd rcx, ecx
mov rax, qword [rbp]
mov word [rax + rcx*2], r12w
jmp 0x100025f6b
mov ecx, 0x80070057
call fcn.1000201f8
int3
mov ecx, 0x80070057
call fcn.1000201f8
int3
mov rcx, r14
call qword [sym.imp.KERNEL32.dll_UnmapViewOfFile]
mov rdi, qword [rsp + 0x40]
mov rcx, qword [rsp + 0x48]
call qword [sym.imp.KERNEL32.dll_CloseHandle]
mov rcx, rdi
call qword [sym.imp.KERNEL32.dll_CloseHandle]
mov rax, rbp
mov rbx, qword [rsp + 0xa8]
add rsp, 0x60
pop r15
pop r14
pop r13
pop r12
pop rdi
pop rsi
pop rbp
ret