Subject: iproute2 mpls max labels

From: Magnus Bergroth <[email-masked]>
Date: Sat, 16 Jul 2016 20:24:48 +0200

Wanted to use more than the default maximum of 8 mpls labels. Max labels
seems to be hardcode to 8 in two places.

--- iproute2-4.6.0/lib/utils.c    2016-05-18 20:56:02.000000000 +0200
+++ iproute2-4.6.0-bergroth/lib/utils.c    2016-07-16 20:12:10.714958071
+0200
@@ -476,7 +476,7 @@
         addr->bytelen = 4;
         addr->bitlen = 20;
         /* How many bytes do I need? */
-        for (i = 0; i < 8; i++) {
+        for (i = 0; i < MPLS_MAX_LABELS; i++) {
             if (ntohl(addr->data[i]) & MPLS_LS_S_MASK) {
                 addr->bytelen = (i + 1)*4;
                 break;

--- iproute2-4.6.0/include/utils.h    2016-05-18 20:56:02.000000000 +0200
+++ iproute2-4.6.0-bergroth/include/utils.h    2016-07-15
11:55:57.297681742 +0200
@@ -54,6 +54,9 @@
 #define NEXT_ARG_FWD() do { argv++; argc--; } while(0)
 #define PREV_ARG() do { argv--; argc++; } while(0)

+/* Maximum number of labels the mpls helpers support */
+#define MPLS_MAX_LABELS 8
+
 typedef struct
 {
     __u16 flags;
@@ -61,7 +64,7 @@
     __s16 bitlen;
     /* These next two fields match rtvia */
     __u16 family;
-    __u32 data[8];
+    __u32 data[MPLS_MAX_LABELS];
 } inet_prefix;

 #define PREFIXLEN_SPECIFIED 1
@@ -88,9 +91,6 @@
 # define AF_MPLS 28
 #endif

-/* Maximum number of labels the mpls helpers support */
-#define MPLS_MAX_LABELS 8
-
 __u32 get_addr32(const char *name);
 int get_addr_1(inet_prefix *dst, const char *arg, int family);
 int get_prefix_1(inet_prefix *dst, char *arg, int family);

Kindly

Magnus Bergroth