openwrt-routing/mcproxy/patches/0003-add-sourcefilter.patch

Index: mcproxy-2017-08-24-93b5ace42268160ebbfff4c61818fb15fa2d9b99/mcproxy/src/utils/mc_socket.cpp
===================================================================
--- mcproxy-2017-08-24-93b5ace42268160ebbfff4c61818fb15fa2d9b99.orig/mcproxy/src/utils/mc_socket.cpp
+++ mcproxy-2017-08-24-93b5ace42268160ebbfff4c61818fb15fa2d9b99/mcproxy/src/utils/mc_socket.cpp
@@ -37,6 +37,10 @@
 #include <numeric>
 #include <unistd.h>
 
+#if !defined(__GLIBC__) || defined(__UCLIBC__)
+#include "sourcefilter.cpp"
+#endif /* __GLIBC__ */
+
 std::string ipAddrResolver(std::string ipAddr)
 {
     std::string str[][2] = {
Index: mcproxy-2017-08-24-93b5ace42268160ebbfff4c61818fb15fa2d9b99/mcproxy/src/utils/sourcefilter.cpp
===================================================================
--- /dev/null
+++ mcproxy-2017-08-24-93b5ace42268160ebbfff4c61818fb15fa2d9b99/mcproxy/src/utils/sourcefilter.cpp
@@ -0,0 +1,165 @@
+/* Get source filter.  Linux version.
+   Copyright (C) 2004-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2004.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <assert.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <netinet/in.h>
+#include <netpacket/packet.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+
+static const struct
+{
+  int sol;
+  int af;
+  socklen_t size;
+}  sol_map[] =
+  {
+    /* Sort the array according to importance of the protocols.  Add
+       more protocols when they become available.  */
+    { SOL_IP, AF_INET, sizeof (struct sockaddr_in) },
+    { SOL_IPV6, AF_INET6, sizeof (struct sockaddr_in6) },
+    { SOL_PACKET, AF_PACKET, sizeof (struct sockaddr_ll) }
+  };
+#define NSOL_MAP (sizeof (sol_map) / sizeof (sol_map[0]))
+
+
+/* Try to determine the socket level value.  Ideally both side and
+   family are set.  But sometimes only the size is correct and the
+   family value might be bogus.  Loop over the array entries and look
+   for a perfect match or the first match based on size.  */
+static int
+__get_sol (int af, socklen_t len)
+{
+  int first_size_sol = -1;
+
+  for (size_t cnt = 0; cnt < NSOL_MAP; ++cnt)
+    {
+      /* Just a test so that we make sure the special value used to
+	 signal the "we have so far no socket level value" is OK.  */
+      assert (sol_map[cnt].sol != -1);
+
+      if (len == sol_map[cnt].size)
+	{
+	  /* The size matches, which is a requirement.  If the family
+	     matches, too, we have a winner.  Otherwise we remember the
+	     socket level value for this protocol if it is the first
+	     match.  */
+	  if (af == sol_map[cnt].af)
+	    /* Bingo!  */
+	    return sol_map[cnt].sol;
+
+	  if (first_size_sol == -1)
+	    first_size_sol = sol_map[cnt].sol;
+      }
+    }
+
+  return first_size_sol;
+}
+
+
+int
+getsourcefilter (int s, uint32_t interface, const struct sockaddr *group,
+		 socklen_t grouplen, uint32_t *fmode, uint32_t *numsrc,
+		 struct sockaddr_storage *slist)
+{
+  /* We have to create an struct ip_msfilter object which we can pass
+     to the kernel.  */
+  socklen_t needed = GROUP_FILTER_SIZE (*numsrc);
+  struct group_filter *gf;
+  gf = (struct group_filter *) malloc (needed);
+  if (gf == NULL)
+    return -1;
+
+  gf->gf_interface = interface;
+  memcpy (&gf->gf_group, group, grouplen);
+  gf->gf_numsrc = *numsrc;
+
+  /* We need to provide the appropriate socket level value.  */
+  int result;
+  int sol = __get_sol (group->sa_family, grouplen);
+  if (sol == -1)
+    {
+      errno = EINVAL;
+      result = -1;
+    }
+  else
+    {
+      result = getsockopt (s, sol, MCAST_MSFILTER, gf, &needed);
+
+      /* If successful, copy the results to the places the caller wants
+	 them in.  */
+      if (result == 0)
+	{
+	  *fmode = gf->gf_fmode;
+	  memcpy (slist, gf->gf_slist,
+		  MIN (*numsrc, gf->gf_numsrc)
+		  * sizeof (struct sockaddr_storage));
+	  *numsrc = gf->gf_numsrc;
+	}
+    }
+
+    int save_errno = errno;
+    free (gf);
+    errno = save_errno;
+
+  return result;
+}
+
+
+int
+setsourcefilter (int s, uint32_t interface, const struct sockaddr *group,
+		 socklen_t grouplen, uint32_t fmode, uint32_t numsrc,
+		 const struct sockaddr_storage *slist)
+{
+  /* We have to create an struct ip_msfilter object which we can pass
+     to the kernel.  */
+  size_t needed = GROUP_FILTER_SIZE (numsrc);
+
+  struct group_filter *gf;
+  gf = (struct group_filter *) malloc (needed);
+  if (gf == NULL)
+    return -1;
+
+  gf->gf_interface = interface;
+  memcpy (&gf->gf_group, group, grouplen);
+  gf->gf_fmode = fmode;
+  gf->gf_numsrc = numsrc;
+  memcpy (gf->gf_slist, slist, numsrc * sizeof (struct sockaddr_storage));
+
+  /* We need to provide the appropriate socket level value.  */
+  int result;
+  int sol = __get_sol (group->sa_family, grouplen);
+  if (sol == -1)
+    {
+      errno = EINVAL;
+      result = -1;
+    }
+  else
+    result = setsockopt (s, sol, MCAST_MSFILTER, gf, needed);
+
+  int save_errno = errno;
+  free (gf);
+  errno = save_errno;
+
+  return result;
+}