zebra/zebra_mpls_netlink.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* MPLS forwarding table updates using netlink over GNU/Linux system.
   3  * Copyright (C) 2016  Cumulus Networks, Inc.
   4  */
   5
   6 #include <zebra.h>
   7
   8 #ifdef HAVE_NETLINK
   9
  10 #include "zebra/debug.h"
  11 #include "zebra/rt.h"
  12 #include "zebra/rt_netlink.h"
  13 #include "zebra/zebra_mpls.h"
  14 #include "zebra/kernel_netlink.h"
  15
  16 ssize_t netlink_lsp_msg_encoder(struct zebra_dplane_ctx *ctx, void *buf,
  17                                 size_t buflen)
  18 {
  19         int cmd;
  20
  21         /* Call to netlink layer based on type of update */
  22         if (dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_DELETE) {
  23                 cmd = RTM_DELROUTE;
  24         } else if (dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_INSTALL ||
  25                    dplane_ctx_get_op(ctx) == DPLANE_OP_LSP_UPDATE) {
  26
  27                 /* Validate */
  28                 if (dplane_ctx_get_best_nhlfe(ctx) == NULL) {
  29                         if (IS_ZEBRA_DEBUG_KERNEL || IS_ZEBRA_DEBUG_MPLS)
  30                                 zlog_debug("LSP in-label %u: update fails, no best NHLFE",
  31                                            dplane_ctx_get_in_label(ctx));
  32                         return -1;
  33                 }
  34
  35                 cmd = RTM_NEWROUTE;
  36         } else
  37                 /* Invalid op? */
  38                 return -1;
  39
  40         return netlink_mpls_multipath_msg_encode(cmd, ctx, buf, buflen);
  41 }
  42
  43 enum netlink_msg_status netlink_put_lsp_update_msg(struct nl_batch *bth,
  44                                                    struct zebra_dplane_ctx *ctx)
  45 {
  46         return netlink_batch_add_msg(bth, ctx, netlink_lsp_msg_encoder, false);
  47 }
  48
  49 /*
  50  * Pseudowire update api - not supported by netlink as of 12/18,
  51  * but note that the default has been to report 'success' for pw updates
  52  * on unsupported platforms.
  53  */
  54 enum netlink_msg_status netlink_put_pw_update_msg(struct nl_batch *bth,
  55                                                   struct zebra_dplane_ctx *ctx)
  56 {
  57         return FRR_NETLINK_SUCCESS;
  58 }
  59
  60 int mpls_kernel_init(void)
  61 {
  62         struct stat st;
  63
  64         /*
  65          * Check if the MPLS module is loaded in the kernel.
  66          */
  67         if (stat("/proc/sys/net/mpls", &st) != 0)
  68                 return -1;
  69
  70         return 0;
  71 };
  72
  73 #endif /* HAVE_NETLINK */