/*

 * Copyright (c) 2016 Darren Tucker.  All rights reserved.

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

#include "includes.h"

#include <sys/types.h>

#ifdef HAVE_SYS_PROCCTL_H

#include <sys/procctl.h>

#endif

#if defined(HAVE_SYS_PRCTL_H)

#include <sys/prctl.h>  /* For prctl() and PR_SET_DUMPABLE */

#endif

#ifdef HAVE_SYS_PTRACE_H

#include <sys/ptrace.h>

#endif

#ifdef HAVE_PRIV_H

#include <priv.h> /* For setpflags() and __PROC_PROTECT  */

#endif

#include <stdarg.h>

#include <stdio.h>

#include <string.h>

#include <unistd.h>

#include "log.h"

void

platform_disable_tracing(int strict)

{

#if defined(HAVE_PROCCTL) && defined(PROC_TRACE_CTL)

  /* On FreeBSD, we should make this process untraceable */

  int disable_trace = PROC_TRACE_CTL_DISABLE;

  /*

   * On FreeBSD, we should make this process untraceable.

   * pid=0 means "this process" but some older kernels do not

   * understand that so retry with our own pid before failing.

   */

  if (procctl(P_PID, 0, PROC_TRACE_CTL, &disable_trace) == 0)

    return;

  if (procctl(P_PID, getpid(), PROC_TRACE_CTL, &disable_trace) == 0)

    return;

  if (strict)

    fatal("unable to make the process untraceable: %s",

        strerror(errno));

#endif

#if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE)

  /* Disable ptrace on Linux without sgid bit */

  if (prctl(PR_SET_DUMPABLE, 0) != 0 && strict)

    fatal("unable to make the process undumpable: %s",

        strerror(errno));

#endif

#if defined(HAVE_SETPFLAGS) && defined(__PROC_PROTECT)

  /* On Solaris, we should make this process untraceable */

  if (setpflags(__PROC_PROTECT, 1) != 0 && strict)

    fatal("unable to make the process untraceable: %s",

        strerror(errno));

#endif

#ifdef PT_DENY_ATTACH

  /* Mac OS X */

  if (ptrace(PT_DENY_ATTACH, 0, 0, 0) == -1 && strict)

    fatal("unable to set PT_DENY_ATTACH: %s", strerror(errno));

#endif

}