pimd: Start work for handling of register command

Start the coding of the REGISTER receive and send.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

pimd/Makefile.am

@@ -54,7 +54,7 @@ libpim_a_SOURCES = \
 	pim_hello.c pim_ifchannel.c pim_join.c pim_assert.c \
 	pim_msg.c pim_upstream.c pim_rpf.c pim_macro.c \
 	pim_igmp_join.c pim_ssmpingd.c pim_int.c pim_rp.c \
-	pim_static.c pim_br.c
+	pim_static.c pim_br.c pim_register.c
 
 noinst_HEADERS = \
 	pimd.h pim_version.h pim_cmd.h pim_signals.h pim_iface.h \
@@ -64,7 +64,7 @@ noinst_HEADERS = \
 	pim_hello.h pim_ifchannel.h pim_join.h pim_assert.h \
 	pim_msg.h pim_upstream.h pim_rpf.h pim_macro.h \
 	pim_igmp_join.h pim_ssmpingd.h pim_int.h pim_rp.h \
-	pim_static.h pim_br.h
+	pim_static.h pim_br.h pim_register.h
 
 pimd_SOURCES = \
 	pim_main.c $(libpim_a_SOURCES)

pimd/pim_register.c

@@ -0,0 +1,188 @@
+/*
+ * PIM for Quagga
+ * Copyright (C) 2015 Cumulus Networks, Inc.
+ * Donald Sharp
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+
+#include <zebra.h>
+
+#include "log.h"
+#include "if.h"
+#include "thread.h"
+
+#include "pimd.h"
+#include "pim_str.h"
+#include "pim_rp.h"
+#include "pim_register.h"
+#include "pim_br.h"
+
+struct thread *send_test_packet_timer = NULL;
+
+/*
+ * This seems stupidly expensive.  A list lookup.  Why is this
+ * not a hash?
+ */
+static int
+pim_check_is_my_ip_address (struct in_addr dest_addr)
+{
+  /*
+   * See if we can short-cut some?
+   * This might not make sense if we ever leave a static RP
+   * type of configuration.
+   * Note - Premature optimization might bite our patooeys' here.
+   */
+  if (I_am_RP(dest_addr) && (dest_addr.s_addr == qpim_rp.s_addr))
+    return 1;
+
+  if (if_lookup_exact_address (&dest_addr, AF_INET))
+    return 1;
+
+  return 0;
+}
+
+static void
+pim_register_stop_send (struct in_addr src)
+{
+  return;
+}
+
+/*
+ * 4.4.2 Receiving Register Messages at the RP
+ *
+ *   When an RP receives a Register message, the course of action is
+ *  decided according to the following pseudocode:
+ *
+ *  packet_arrives_on_rp_tunnel( pkt ) {
+ *      if( outer.dst is not one of my addresses ) {
+ *          drop the packet silently.
+ *          # Note: this may be a spoofing attempt
+ *      }
+ *      if( I_am_RP(G) AND outer.dst == RP(G) ) {
+ *            sentRegisterStop = FALSE;
+ *            if ( register.borderbit == TRUE ) {
+ *                 if ( PMBR(S,G) == unknown ) {
+ *                      PMBR(S,G) = outer.src
+ *                 } else if ( outer.src != PMBR(S,G) ) {
+ *                      send Register-Stop(S,G) to outer.src
+ *                      drop the packet silently.
+ *                 }
+ *            }
+ *            if ( SPTbit(S,G) OR
+ *             ( SwitchToSptDesired(S,G) AND
+ *               ( inherited_olist(S,G) == NULL ))) {
+ *              send Register-Stop(S,G) to outer.src
+ *              sentRegisterStop = TRUE;
+ *            }
+ *            if ( SPTbit(S,G) OR SwitchToSptDesired(S,G) ) {
+ *                 if ( sentRegisterStop == TRUE ) {
+ *                      set KeepaliveTimer(S,G) to RP_Keepalive_Period;
+ *                 } else {
+ *                      set KeepaliveTimer(S,G) to Keepalive_Period;
+ *                 }
+ *            }
+ *            if( !SPTbit(S,G) AND ! pkt.NullRegisterBit ) {
+ *                 decapsulate and forward the inner packet to
+ *                 inherited_olist(S,G,rpt) # Note (+)
+ *            }
+ *      } else {
+ *          send Register-Stop(S,G) to outer.src
+ *          # Note (*)
+ *      }
+ *  }
+ */
+int
+pim_register_recv (struct interface *ifp,
+		   struct in_addr dest_addr,
+		   struct in_addr src_addr,
+		   uint8_t *tlv_buf, int tlv_buf_size)
+{
+  //int sentRegisterStop = 0;
+  struct in_addr group = { .s_addr = 0 };
+  struct in_addr source = { .s_addr = 0 };
+  struct in_addr outer_src = { .s_addr = 0 };
+  uint32_t *bits = (uint32_t *)tlv_buf;
+  //uint8_t *data = (tlv_buf + sizeof(uint32_t));
+  uint32_t nrb;
+
+  if (!pim_check_is_my_ip_address (dest_addr)) {
+    if (PIM_DEBUG_PIM_PACKETS) {
+      char dest[100];
+
+      pim_inet4_dump ("<dst?>", dest_addr, dest, sizeof(dest));
+      zlog_debug ("%s: Received Register message for %s that I do not own", __func__,
+		  dest);
+    }
+    return 0;
+  }
+
+  nrb = (*bits && PIM_REGISTER_NR_BIT);
+  if (I_am_RP (group) && (dest_addr.s_addr == (RP (group).s_addr))) {
+    //sentRegisterStop = 0;
+
+    if (*bits && PIM_REGISTER_BORDER_BIT) {
+      struct in_addr pimbr = pim_br_get_pmbr (source, group);
+      if (PIM_DEBUG_PIM_PACKETS)
+	zlog_debug("%s: Received Register message with Border bit set", __func__);
+
+      if (pimbr.s_addr == pim_br_unknown.s_addr)
+	pim_br_set_pmbr(source, group, outer_src);
+      else if (outer_src.s_addr != pimbr.s_addr) {
+	pim_register_stop_send(outer_src);
+	if (PIM_DEBUG_PIM_PACKETS)
+	  zlog_debug("%s: Sending register-Stop to %s and dropping mr. packet",
+	    __func__, "Sender");
+      }
+    }
+  } else {
+      nrb++;
+    //pim_recv_
+    }
+
+  return 1;
+}
+
+
+static int
+pim_register_send_test_packet (struct thread *t)
+{
+  uint8_t *packet;
+
+  packet = THREAD_ARG(t);
+
+  *packet = 4;
+
+  return 1;
+}
+
+/*
+ * pim_register_send_test_packet
+ *
+ * Send a test packet to the RP from source, in group and pps packets per second
+ */
+void
+pim_register_send_test_packet_start (struct in_addr source,
+				     struct in_addr group,
+				     uint32_t pps)
+{
+  uint8_t *packet = NULL;
+
+  THREAD_TIMER_MSEC_ON(master, send_test_packet_timer,
+		       pim_register_send_test_packet, packet, 1000/pps);
+
+  return;
+}

pimd/pim_register.h

@@ -0,0 +1,40 @@
+/*
+ * PIM for Quagga
+ * Copyright (C) 2015 Cumulus Networks, Inc.
+ * Donald Sharp
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+#ifndef PIM_REGISTER_H
+#define PIM_REGISTER_H
+
+#include <zebra.h>
+
+#include "if.h"
+
+#define PIM_REGISTER_BORDER_BIT 0x80000000
+#define PIM_REGISTER_NR_BIT     0x40000000
+
+void pim_register_send_test_packet_start (struct in_addr source,
+					  struct in_addr group,
+					  uint32_t pps);
+
+int pim_register_recv (struct interface *ifp,
+		       struct in_addr dest_addr,
+		       struct in_addr src_addr,
+		       uint8_t *tlv_buf, int tlv_buf_size);
+
+#endif