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ptrace ex 6
#include <sys/ptrace.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <signal.h>
#include <sys/user.h>
#include <sys/reg.h>
int waitchild(pid_t pid) {
int status;
waitpid(pid, &status, 0);
if(WIFSTOPPED(status)) {
return 0;
}
else if (WIFEXITED(status)) {
return 1;
}
else {
printf("%d raised an unexpected status %d", pid, status);
return 1;
}
}
unsigned long to_ulong(char * s) {
return strtol(s, NULL, 16);
}
unsigned long readRegister(pid_t tracee, int reg) {
return ptrace(PTRACE_PEEKUSER, tracee, 8 * reg, NULL);
}
void showregisters(pid_t tracee) {
printf("RIP = %lx\n",
readRegister(tracee, RIP));
}
void presskey() {
getchar();
}
int main(int argc, char ** argv) {
unsigned long bpAddress = to_ulong(argv[1]);
pid_t child = fork();
unsigned long rip;
if(child == 0) {
ptrace(PTRACE_TRACEME, 0, NULL, NULL);
execve(argv[2], argv + 2, NULL);
}
else {
// wait for the child to stop
waitchild(child);
do {
rip = readRegister(child, RIP);
if(rip == bpAddress) {
showregisters(child);
presskey();
}
ptrace(PTRACE_SINGLESTEP, child, NULL, NULL);
} while(waitchild(child) < 1);
}
return 0;
}
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