CS 456 - Systems Programming Spring 2024

Displaying ./code/apr10/socket_L31.asm

; Socket
; Compile with: nasm -f elf socket.asm
; Link with (64 bit systems require elf_i386 option): ld -m elf_i386 socket.o -o socket
; Run with: ./socket
 
%include    'functions.asm'
 
SECTION .text
global  _start
 
_start:
 
    xor     eax, eax            ; init eax 0
    xor     ebx, ebx            ; init ebx 0
    xor     edi, edi            ; init edi 0
    xor     esi, esi            ; init esi 0
 
_socket:
 
    push    byte 6              ; push 6 onto the stack (IPPROTO_TCP)
    push    byte 1              ; push 1 onto the stack (SOCK_STREAM)
    push    byte 2              ; push 2 onto the stack (PF_INET)
    mov     ecx, esp            ; move address of arguments into ecx
    mov     ebx, 1              ; invoke subroutine SOCKET (1)
    mov     eax, 102            ; invoke SYS_SOCKETCALL (kernel opcode 102)
    int     80h                 ; call the kernel
 
_bind:
 
    mov     edi, eax            ; move return value of SYS_SOCKETCALL into edi (file descriptor for new socket, or -1 on error)
    push    dword 0x00000000    ; push 0 dec onto the stack IP ADDRESS (0.0.0.0)
    push    word 0x2923         ; push 9001 dec onto stack PORT (reverse byte order)
    push    word 2              ; push 2 dec onto stack AF_INET
    mov     ecx, esp            ; move address of stack pointer into ecx
    push    byte 16             ; push 16 dec onto stack (arguments length)
    push    ecx                 ; push the address of arguments onto stack
    push    edi                 ; push the file descriptor onto stack
    mov     ecx, esp            ; move address of arguments into ecx
    mov     ebx, 2              ; invoke subroutine BIND (2)
    mov     eax, 102            ; invoke SYS_SOCKETCALL (kernel opcode 102)
    int     80h                 ; call the kernel

_listen:
 
    push    byte 1              ; move 1 onto stack (max queue length argument)
    push    edi                 ; push the file descriptor onto stack
    mov     ecx, esp            ; move address of arguments into ecx
    mov     ebx, 4              ; invoke subroutine LISTEN (4)
    mov     eax, 102            ; invoke SYS_SOCKETCALL (kernel opcode 102)
    int     80h                 ; call the kernel
  
_exit:
 
    call    quit                ; call our quit function