level04: source code done

level04/source.c

@@ -0,0 +1,42 @@
+#include <stdio.h>
+#include <string.h>
+#include <sys/prctl.h>
+#include <sys/ptrace.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+int main(void)
+{
+	int stat_loc;
+	char s[128];
+	int v6;
+	int v7;
+	int v8;
+	pid_t v9;
+
+	v9 = fork();
+	memset(s, 0, sizeof(s));
+	v8 = 0;
+	stat_loc = 0;
+	if (v9) {
+		do {
+			wait(&stat_loc);
+			v6 = stat_loc;
+			if ((stat_loc & 0x7F) == 0 ||
+			    (v7 = stat_loc,
+			     (char)((stat_loc & 0x7F) + 1) >> 1 > 0)) {
+				puts("child is exiting...");
+				return 0;
+			}
+			v8 = ptrace(PTRACE_PEEKUSER, v9, 44, 0);
+		} while (v8 != 11);
+		puts("no exec() for you");
+		kill(v9, 9);
+	} else {
+		prctl(1, 1);
+		ptrace(PTRACE_TRACEME, 0, 0, 0);
+		puts("Give me some shellcode, k");
+		gets(s);
+	}
+	return 0;
+}