initial commit

diff --git a/rg.c b/rg.c
new file mode 100644 (file)
index 0000000..1c286fc
--- /dev/null
+++ b/rg.c
@@ -0,0 +1,76 @@
+// Copyright (C) Jann Horn (2013)
+// You can redistribute this code under the terms of the GPLv2 or GPLv3.
+// THIS PROGRAM IS FOR EDUCATIONAL PURPOSES ONLY!
+// I AM NOT RESPONSIBLE FOR WHAT YOU DO WITH THIS PROGRAM OR THE IMPACT THIS
+// PROGRAM MIGHT HAVE ON YOUR SYSTEMS! YOU HAVE BEEN WARNED!
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <time.h>
+#include <unistd.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+char *target;
+
+void run(void) {
+  int pipefds[2];
+  if (pipe(pipefds)) perror("can't create pipe"), exit(1);
+  int parent_fd = pipefds[0];
+  int child_fd = pipefds[1];
+
+  pid_t pid = fork();
+  if (pid < 0) perror("can't fork"), exit(1);
+
+  if (pid == 0) {
+    int nullfd = open("/dev/null", O_RDWR);
+    dup2(nullfd, 0);
+    dup2(nullfd, 2);
+    close(nullfd);
+    close(parent_fd);
+    dup2(child_fd, 1);
+    close(child_fd);
+    execlp("hping3", "hping3", "-c", "20", "-p", "80", "-i", "u100000", "--syn", target, NULL);
+    perror("can't exec"), exit(1);
+  }
+  close(child_fd);
+
+  char indata[4096];
+  int indata_written = 0;
+  int rres;
+  while ((rres=read(parent_fd, indata+indata_written, 4095-indata_written)) > 0) {
+    indata_written += rres;
+    if (indata_written >= 4095) fputs("too much information", stderr), exit(1);
+  }
+  if (rres < 0) perror("failure reading from child"), exit(1);
+  indata[indata_written] = '\0';
+  close(parent_fd);
+
+  char *s = indata;
+  int last_id = -1;
+  int sum = 0;
+  while ((s=strstr(s, " id=")) != NULL) {
+    s += 4;
+    int id = atoi(s);
+    if (last_id != -1) {
+      int diff = id - last_id;
+      if (diff < 0) diff += (256*256);
+      sum += diff;
+    }
+    last_id = id;
+  }
+
+  printf("%i %i\n", (int)time(NULL), sum);
+}
+
+int main(int argc, char **argv) {
+  if (argc != 2) fputs("bad invocation\n", stderr), exit(1);
+  target = argv[1];
+
+  while (1) {
+    run();
+    sleep(300);
+  }
+}