On 7/16/16, 11:24 AM, Magnus Bergroth wrote:
> 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);
>
>
I did not realize it is hardcoded to 8 in iproute2. Because kernel has a hard
coded limit of
2.
I think we need to fix it in a few places:
a) we should move the kernel #define to a uapi header file which iproute2 can
use
b) there has been a general ask to bump the kernel MAX_LABELS from 2 and I
don't see
a problem with it yet. so, we could bump it to 8.
Were you planning to post patches for one or both of the above ?.
I can post them too. Let me know.
Thanks,
Roopa
