┌──(kali㉿kali)-[~/code]
└─$ wget https://artifacts.picoctf.net/c/511/disassembler-dump0_d.txt
--2023-07-30 23:35:20--  https://artifacts.picoctf.net/c/511/disassembler-dump0_d.txt
Resolving artifacts.picoctf.net (artifacts.picoctf.net)... 13.35.7.96, 13.35.7.121, 13.35.7.31, ...
Connecting to artifacts.picoctf.net (artifacts.picoctf.net)|13.35.7.96|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 482 [application/octet-stream]
Saving to: ‘disassembler-dump0_d.txt’

disassembler-dump0_d.txt            100%[=================================================================>]     482  --.-KB/s    in 0s      

2023-07-30 23:35:23 (9.87 MB/s) - ‘disassembler-dump0_d.txt’ saved [482/482]

                                                                                                                                              
┌──(kali㉿kali)-[~/code]
└─$ cat disassembler-dump0_d.txt
<+0>:     endbr64 
<+4>:     push   rbp
<+5>:     mov    rbp,rsp
<+8>:     mov    DWORD PTR [rbp-0x14],edi
<+11>:    mov    QWORD PTR [rbp-0x20],rsi
<+15>:    mov    DWORD PTR [rbp-0x4],0x9fe1a
<+22>:    cmp    DWORD PTR [rbp-0x4],0x2710
<+29>:    jle    0x55555555514e <main+37>
<+31>:    sub    DWORD PTR [rbp-0x4],0x65
<+35>:    jmp    0x555555555152 <main+41>
<+37>:    add    DWORD PTR [rbp-0x4],0x65
<+41>:    mov    eax,DWORD PTR [rbp-0x4]
<+44>:    pop    rbp
<+45>:    ret

┌──(kali㉿kali)-[~/code]
└─$ python3
Python 3.11.2 (main, Mar 13 2023, 12:18:29) [GCC 12.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 0x9fe1a
654874
>>> 0x2710
10000
>>> 0x9fe1a-0x65
654773

## study materials:`cmp` & `jle`

The x86 assembly uses a system of bit-flags that represent the result of comparisons. The conditional jump instructions use these flags when deciding whether to perform the jump or not.

In your case you'd use the following two instructions:

cmp ebx, 10     ; compare EBX and 10
jle label       ; jump if EBX is "less than or equal" to 10
…
label:
…

Here is a simple example of an if/else that stores to one of two different locations, depending on ebx <= 10. The mov store instructions are the if and else blocks.

.model small
.code
start : 
    mov ebx , 20    ( we insert 20 in ebx ) 
    CMP ebx , 10    ( we compare 20 with 10 ) 
    JBE there       ( Jump if below or equal to there ) 
    mov [1020h] , ebx   ( else we move ebx to [1020h] )
    JMP exit     ; don't fall into the else part
there:
    mov [1030h] , ebx ( If ebx <= 10 we move ebx to [1030h] ) 
    ;JMP exit     ; redundant: execution falls through to exit on its own

exit:      ( define a label that other instructions can jump to)
    mov ax, 4c00h
    int 21h             ; 16-bit DOS exit system call
end start 

(source: https://stackoverflow.com/questions/4557279/assembly-jle-jmp-instruction-example)