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 ssize_t netlink_lsp_msg_encoder(struct zebra_dplane_ctx *ctx, void *buf,
  32                                 size_t buflen)
  33 {
  34         int cmd;
  35
  36         /* Call to netlink layer based on type of update */
  37         if (dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_DELETE) {
  38                 cmd = RTM_DELROUTE;
  39         } else if (dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_INSTALL ||
  40                    dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_UPDATE) {
  41
  42                 /* Validate */
  43                 if (dplane_ctx_get_best_nhlfe(ctx) == NULL) {
  44                         if (IS_ZEBRA_DEBUG_KERNEL || IS_ZEBRA_DEBUG_MPLS)
  45                                 zlog_debug("LSP in-label %u: update fails, no best NHLFE",
  46                                            dplane_ctx_get_in_label(ctx));
  47                         return -1;
  48                 }
  49
  50                 cmd = RTM_NEWROUTE;
  51         } else
  52                 /* Invalid op? */
  53                 return -1;
  54
  55         return netlink_mpls_multipath_msg_encode(cmd, ctx, buf, buflen);
  56 }
  57
  58 enum netlink_msg_status netlink_put_lsp_update_msg(struct nl_batch *bth,
  59                                                    struct zebra_dplane_ctx *ctx)
  60 {
  61         return netlink_batch_add_msg(bth, ctx, netlink_lsp_msg_encoder, false);
  62 }
  63
  64 /*
  65  * Pseudowire update api - not supported by netlink as of 12/18,
  66  * but note that the default has been to report 'success' for pw updates
  67  * on unsupported platforms.
  68  */
  69 enum netlink_msg_status netlink_put_pw_update_msg(struct nl_batch *bth,
  70                                                   struct zebra_dplane_ctx *ctx)
  71 {
  72         return FRR_NETLINK_SUCCESS;
  73 }
  74
  75 int mpls_kernel_init(void)
  76 {
  77         struct stat st;
  78
  79         /*
  80          * Check if the MPLS module is loaded in the kernel.
  81          */
  82         if (stat("/proc/sys/net/mpls", &st) != 0)
  83                 return -1;
  84
  85         return 0;
  86 };
  87
  88 #endif /* HAVE_NETLINK */