MPLS subsystem

The MPLS subsystem manages MPLS labels and handles their allocation to
MPLS-aware routing protocols. These labels are then attached to IP or VPN
routes representing label switched paths -- LSPs.

There was already a preliminary MPLS support consisting of MPLS label
net_addr, MPLS routing tables with static MPLS routes, remote labels in
next hops, and kernel protocol support.

This patch adds the MPLS domain as a basic structure representing local
label space with dynamic label allocator and configurable label ranges.
To represent LSPs, allocated local labels can be attached as route
attributes to IP or VPN routes with local labels as attributes.

There are several steps for handling LSP routes in routing protocols --
deciding to which forwarding equivalence class (FEC) the LSP route
belongs, allocating labels for new FECs, announcing MPLS routes for new
FECs, attaching labels to LSP routes. The FEC map structure implements
basic code for managing FECs in routing protocols, therefore existing
protocols can be made MPLS-aware by adding FEC map and delegating
most work related to local label management to it.

2 files changed, 10 insertions, 1 deletions

diff --git a/sysdep/unix/krt.Y b/sysdep/unix/krt.Y
index 95b54d65..5af6a4c8 100644
--- a/sysdep/unix/krt.Y
+++ b/sysdep/unix/krt.Y
@@ -33,6 +33,7 @@ CF_KEYWORDS(KERNEL, PERSIST, SCAN, TIME, LEARN, DEVICE, ROUTES, GRACEFUL, RESTAR
 CF_KEYWORDS(INTERFACE, PREFERRED)
 
 %type <i> kern_mp_limit
+%type <cc> kern_channel
 
 CF_GRAMMAR
 
@@ -53,9 +54,15 @@ kern_mp_limit:
  | LIMIT expr  { $$ = $2; if (($2 <= 0) || ($2 > 255)) cf_error("Merge paths limit must be in range 1-255"); }
  ;
 
+
+kern_channel:
+   proto_channel
+ | mpls_channel
+ ;
+
 kern_item:
    proto_item
- | proto_channel { this_proto->net_type = $1->net_type; }
+ | kern_channel { this_proto->net_type = $1->net_type; }
  | PERSIST bool { THIS_KRT->persist = $2; }
  | SCAN TIME expr {
       /* Scan time of 0 means scan on startup only */
diff --git a/sysdep/unix/main.c b/sysdep/unix/main.c
index 23cadb14..0d7788bb 100644
--- a/sysdep/unix/main.c
+++ b/sysdep/unix/main.c
@@ -33,6 +33,7 @@
 #include "nest/route.h"
 #include "nest/protocol.h"
 #include "nest/iface.h"
+#include "nest/mpls.h"
 #include "nest/cli.h"
 #include "nest/locks.h"
 #include "conf/conf.h"
@@ -895,6 +896,7 @@ main(int argc, char **argv)
   io_init();
   rt_init();
   if_init();
+  mpls_init();
 //  roa_init();
   config_init();