zebra/zebra_mpls_netlink.c

   1 /* MPLS forwarding table updates using netlink over GNU/Linux system.
   2  * Copyright (C) 2016  Cumulus Networks, Inc.
   3  *
   4  * This file is part of Quagga.
   5  *
   6  * Quagga is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; either version 2, or (at your option) any
   9  * later version.
  10  *
  11  * Quagga is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <zebra.h>
  22
  23 #ifdef HAVE_NETLINK
  24
  25 #include "zebra/debug.h"
  26 #include "zebra/rt.h"
  27 #include "zebra/rt_netlink.h"
  28 #include "zebra/zebra_mpls.h"
  29 #include "zebra/kernel_netlink.h"
  30
  31 /*
  32  * LSP forwarding update using dataplane context information.
  33  */
  34 enum zebra_dplane_result kernel_lsp_update(struct zebra_dplane_ctx *ctx)
  35 {
  36         uint8_t nl_pkt[NL_PKT_BUF_SIZE];
  37         ssize_t ret = -1;
  38         int cmd;
  39
  40         /* Call to netlink layer based on type of update */
  41         if (dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_DELETE) {
  42                 cmd = RTM_DELROUTE;
  43         } else if (dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_INSTALL ||
  44                    dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_UPDATE) {
  45
  46                 /* Validate */
  47                 if (dplane_ctx_get_best_nhlfe(ctx) == NULL) {
  48                         if (IS_ZEBRA_DEBUG_KERNEL || IS_ZEBRA_DEBUG_MPLS)
  49                                 zlog_debug("LSP in-label %u: update fails, no best NHLFE",
  50                                            dplane_ctx_get_in_label(ctx));
  51                         goto done;
  52                 }
  53
  54                 cmd = RTM_NEWROUTE;
  55         } else
  56                 /* Invalid op? */
  57                 goto done;
  58
  59         ret = netlink_mpls_multipath_msg_encode(cmd, ctx, nl_pkt,
  60                                                 sizeof(nl_pkt));
  61         if (ret <= 0)
  62                 return ZEBRA_DPLANE_REQUEST_FAILURE;
  63
  64         ret = netlink_talk_info(netlink_talk_filter, (struct nlmsghdr *)nl_pkt,
  65                                 dplane_ctx_get_ns(ctx), 0);
  66
  67 done:
  68
  69         return (ret == 0 ?
  70                 ZEBRA_DPLANE_REQUEST_SUCCESS : ZEBRA_DPLANE_REQUEST_FAILURE);
  71 }
  72
  73 /*
  74  * Pseudowire update api - not supported by netlink as of 12/18,
  75  * but note that the default has been to report 'success' for pw updates
  76  * on unsupported platforms.
  77  */
  78 enum zebra_dplane_result kernel_pw_update(struct zebra_dplane_ctx *ctx)
  79 {
  80         return ZEBRA_DPLANE_REQUEST_SUCCESS;
  81 }
  82
  83 int mpls_kernel_init(void)
  84 {
  85         struct stat st;
  86
  87         /*
  88          * Check if the MPLS module is loaded in the kernel.
  89          */
  90         if (stat("/proc/sys/net/mpls", &st) != 0)
  91                 return -1;
  92
  93         return 0;
  94 };
  95
  96 #endif /* HAVE_NETLINK */