GCC 10 thinks we memcpy into a 0-sized array (which we're not).
Use a C99 flexible array member instead.
Fixes:
CC lib/stream.lo
lib/stream.c: In function ‘stream_put_in_addr’:
lib/stream.c:824:2: warning: writing 4 bytes into a region of size 0 [-Wstringop-overflow=]
824 | memcpy(s->data + s->endp, addr, sizeof(uint32_t));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
isisd/isis_tlvs.c: In function ‘auth_validator_hmac_md5’:
isisd/isis_tlvs.c:4279:2: warning: writing 16 bytes into a region of size 0 [-Wstringop-overflow=]
4279 | memcpy(STREAM_DATA(stream) + auth->offset, auth->value, 16);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function ‘update_auth_hmac_md5’,
inlined from ‘update_auth’ at isisd/isis_tlvs.c:3734:4,
inlined from ‘isis_pack_tlvs’ at isisd/isis_tlvs.c:3897:2:
isisd/isis_tlvs.c:3722:2: warning: writing 16 bytes into a region of size 0 [-Wstringop-overflow=]
3722 | memcpy(STREAM_DATA(s) + auth->offset, digest, 16);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
isisd/isis_tlvs.c:3722:2: warning: writing 16 bytes into a region of size 0 [-Wstringop-overflow=]
Signed-off-by: Ruben Kerkhof <ruben@rubenkerkhof.com>
Add a common api that formats a time interval into a string
with different output for short and longer intervals. We do
this in several places, for cli/ui output.
Signed-off-by: Mark Stapp <mjs@voltanet.io>
This patch does two things:
1) Ensure the decoding of stream data between pim <-> zebra is properly
decoded and we don't read beyond the end of the stream.
2) In zebra when we are freeing memory alloced ensure that we
actually have memory to delete before we do so.
Ticket: CM-27055
Signed-off-by: Satheesh Kumar K <sathk@cumulusnetworks.com>
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
It's been a year search and destroy.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>
vtysh should handle going back up one level to try the command, there is
no need to be able to recurse inside route-map.
This also fixes a problem with northbound hitting the XPath queue limit
of 8 nodes.
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
Use better TAILQ free idiom to avoid coverity scan warnings. This fixes
the coverity scan issue 1491240 .
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
* This commit implements the code style suggestions from Polychaeta.
* This commit also introduces a CLI to toggle the optimization and, a hidden
CLI to display the contents of the constructed prefix tree.
Signed-off-by: NaveenThanikachalam <nthanikachal@vmware.com>
This commit introduces the logic that computes the best-match route-map index
for a given prefix.
Signed-off-by: NaveenThanikachalam <nthanikachal@vmware.com>
* This commit introduces the building blocks.
A per-route-map prefix tree is introduced.
This tree will consist of the prefixes defined within the prefix-lists
that are added to the match clause of that route-map.
Signed-off-by: NaveenThanikachalam <nthanikachal@vmware.com>
The `--enable-pcreposix` configure option was not actually compiling
properly. Follow pre-existing pattern for inclusion of regex.h
or the pcreposix.h header.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Use the zapi_nexthop struct with the mpls_labels
zapi messages instead of the special-purpose (and
more limited) nexthop struct that was being used.
Signed-off-by: Mark Stapp <mjs@voltanet.io>
This string is used in some logging for e.g. in zclient_read -
>>>>>>>>>>>>>>>>>>>>>>>>>>
if (zclient_debug)
zlog_debug("zclient 0x%p command %s VRF %u",
(void *)zclient, zserv_command_string(command),
vrf_id);
>>>>>>>>>>>>>>>>>>>>>>>>>>
Signed-off-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Add some additional output/debug to code to allow
us to see the vrf name instead of just the vrf id.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Add a quick macro to allow for safe dereference of the vrf
since it may or may not exist in all cases.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
A route where ESI, GW IP, MAC and Label are all zero at the same time SHOULD
be treat-as-withdraw.
Invalid MAC addresses are broadcast or multicast MAC addresses. The route
MUST be treat-as-withdraw in case of an invalid MAC address.
As FRR support Ethernet NVO Tunnels only.
Route will be withdrawn when ESI, GW IP and MAC are zero or Invalid MAC
Test cases:
1) ET-5 route with valid RMAC extended community
2) ET-5 route no RMAC extended community
3) ET-5 route with Multicast MAC in RMAC extended community
4) ET-5 route with Broadcast MAC in RMAC extended community
Signed-off-by: Kishore Aramalla <karamalla@vmware.com>
Copy the fix made in 'lib/if.c' to 'lib/routemap_northbound.c' so we can
have a working YANG model when compiled with GCC version less than 5.
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
Keep a list of hook contexts used by northbound so we don't lose the
pointer when free()ing the route map index entry data.
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
Allow old CLI users to still print their configuration without migrating
to northbound.
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
Two fixes here:
* Don't attempt to use `vty` pointer in vty;
* When `vty` is unavailable output to log;
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
This fixes a warning on daemons that use route map about filter yang
model not being included in the binary.
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
Based on the route map old CLI, implement the route map handling using
the exported functions.
Use a curry-like programming pattern avoid code repetition when
destroying match/set entries. This is needed by other daemons that
implement custom route map functions and need to pass to lib their
specific destroy functions.
Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>
The agentx.c code was calling fcntl but not testing return
code and handling it, thus making SA unhappy.
Fix.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
For Graceful restart clients have to send GR capabilities
library functions are added to encode capabilities and
also for zebra to decode client capabilities.
Co-authored-by: Santosh P K <sapk@vmware.com>
Co-authored-by: Soman K S <somanks@vmware.com>
Signed-off-by: Santosh P K <sapk@vmware.com>
These changes are for Zebra lib in order to supportGraceful Restart
feature. These changes are addedtemporarily, until Zebra Graceful
Restart lib Pr is merged.
Signed-off-by: Biswajit Sadhu <sadhub@vmware.com>
Signed-off-by: Soman K S <somanks@vmware.com>
* Added FSM for peer and global configuration for graceful restart
* Added debug option BGP_GRACEFUL_RESTART for logs specific to
graceful restart processing
Signed-off-by: Biswajit Sadhu <sadhub@vmware.com>
Commit
68a02e06e5 broke nexthop encoding
for nexthop tracking.
This code combined the different types of nexthop encoding
being done in the zapi protocol. What was missed that
resolved nexthops of type NEXTHOP_TYPE_IPV4|6 have an ifindex
value that was not being reported. This commit ensures
that we always send this data( even if it is 0).
The following test commit will ensure that this stays working
as is expected by an upper level protocol.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
This script was written back when `git describe` would abbreviate to
7-char commit IDs; they're longer now and we're grabbing the tail
end...
Signed-off-by: David Lamparter <equinox@diac24.net>
If someone tries to add a nexthop with a list of nexthops
already attached to it, let's just assert. This standardizes
the API to say we assume this is an individual nexthop
you are appending to a group.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Make the nexthop_copy/nexthop_dup APIs more consistent by
adding a secondary, non-recursive, version of them. Before,
it was inconsistent whether the APIs were expected to copy
recursive info or not. Make it clear now that the default is
recursive info is copied unless the _no_recurse() version is
called. These APIs are not heavily used so it is fine to
change them for now.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
bgpd already supports BGP Prefix-SID path attribute and
there are some sub-types of Prefix-SID path attribute.
This commits makes bgpd to support additional sub-types.
sub-Type-4 and sub-Type-5 for construct the VPNv4 SRv6 backend
with vpnv4-unicast address family.
This path attributes is already supported by Ciscos IOS-XR and NX-OS.
Prefix-SID sub-Type-4 and sub-Type-5 is defined on following
IETF-drafts.
Supports(A-part-of):
- https://tools.ietf.org/html/draft-dawra-idr-srv6-vpn-04
- https://tools.ietf.org/html/draft-dawra-idr-srv6-vpn-05
Signed-off-by: Hiroki Shirokura <slank.dev@gmail.com>
Add error handling for top level failures (not able to
execute command, unable to find vrf for command, etc.)
With this error handling we add a new zapi message type
of ZEBRA_ERROR used when we are unable to properly handle
a zapi command and pass it down into the lower level code.
In the event of this, we reply with a message of type
enum zebra_error_types containing the error type.
The sent packet will look like so:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | Marker | Version |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VRF ID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Command |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ERROR TYPE |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Also add appropriate hooks for clients to subscribe to for
handling these types of errors.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
If someone provides us more nexthops than our configured multipath
setting, drop the rest of them
Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>
Commit 1b3e9a21dd removed the global visibility of the yang_modules
variable, breaking the build of all northbound plugins. Revert a
small part of that commit to fix this issue.
Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
Default all nexthop weights to one. The linux kernel does
some weird stuff where it adds one to all nexthop weight values
it gets. So, we added df7fb5800b with
some special subtracing/adding to account for this. Though, that patch
did not account for the default case of the weight being zero for
elements in the group.
Hence, this patch defaults the nexthop weight to one during creation.
This should be a valid value on all platforms anyway so shouldn't
affect anything.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
The whole lib/linklist.c code shouldn't really be used for new code (the
lib/typesafe.h bits are better.) So, a new need for these unused
functions shouldn't be coming up.
Signed-off-by: David Lamparter <equinox@diac24.net>
Sometimes the easiest solution is hardest to find... the whole point of
all this "static const", aliasing, & co. was to make "MTYPE_FOO" usable
without adding the extra & as in "&MTYPE_FOO". Making it a size-1 array
does that perfectly through the magic of ISO C array decay...
Signed-off-by: David Lamparter <equinox@diac24.net>
To keep the calling code agnostic of the DNS resolver libary used, pass
a strerror-style string instead of a status code that would need extra
handling.
Signed-off-by: David Lamparter <equinox@diac24.net>
libc-ares doesn't do IP literals, so we have to do that before running
off to do DNS. Since this isn't BMP specific, move to lib/ so NHRP can
benefit too.
Signed-off-by: David Lamparter <equinox@diac24.net>
Under some circumstances (apparently depends on several optimization
flags), gcc-9 throws an used-uninitialized warning for this variable in
the skiplist code. Just initialize to NULL.
Signed-off-by: David Lamparter <equinox@diac24.net>
Add an api that creates a copy of a list of nexthops and
enforces the canonical sort ordering; consolidate some nhg
code to avoid copy-and-paste. The zebra dplane uses
that api when a plugin sets up a list of nexthops, ensuring
that the plugin's list is ordered when it's processed in
zebra.
Signed-off-by: Mark Stapp <mjs@voltanet.io>
Add the ability to read in the weight of a nexthop and store/handle
it appropriately
nexthop-group BLUE
nexthop 192.168.201.44 weight 33
nexthop 192.168.201.45 weight 66
nexthop 192.168.201.46 weight 99
Is appropriately read in and handled as appropriate.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Linux has the idea of allowing a weight to be sent
down as part of a nexthop group to allow the kernel
to weight particular nexthop paths a bit more or less
than others.
See:
http://tldp.org/HOWTO/Adv-Routing-HOWTO/lartc.rpdb.multiple-links.html
Allow for installation into the kernel using the weight attribute
associated with the nexthop.
This code is foundational in that it just sets up the ability
to do this, we do not use it yet. Further commits will
allow for the pass through of this data from upper level protocols.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Use a per-nexthop flag to indicate the presence of labels; add
some utility zapi encode/decode apis for nexthops; use the zapi
apis more consistently.
Signed-off-by: Mark Stapp <mjs@voltanet.io>
Some preprocessor constants converted to enums to make the names usable
in the preprocessor.
v2: better isolation between core and vty code to make future northbound
conversion easier.
Signed-off-by: David Lamparter <equinox@diac24.net>
This moves all the DFLT_BGP_* stuff over to the new defaults mechanism.
bgp_timers_nondefault() added to get better file-scoping.
v2: moved everything into bgp_vty.c so that the core BGP code is
independent of the CLI-specific defaults. This should make the future
northbound conversion easier.
Signed-off-by: David Lamparter <equinox@diac24.net>
Since we've been writing out "frr version" and "frr defaults" for about
a year and a half now, we can now actually use them to manage defaults.
Signed-off-by: David Lamparter <equinox@diac24.net>
Replace the existing list of nexthops (via a nexthop_group
struct) in the route_entry with a direct pointer to zebra's
new shared group (from zebra_nhg.h). This allows more
direct access to that shared group and the info it carries.
Signed-off-by: Mark Stapp <mjs@voltanet.io>
Add support for labelled nexthops in nexthop-group
vtysh configuration. Also update the PBR doc where
the cli is described.
Signed-off-by: Mark Stapp <mjs@voltanet.io>
Add a function for converting the zapi_rule_notify_owner enum
type to a string for ease of use.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Commit 5e6a9350c1 implemented an optimization where candidate
configurations are validated only before being displayed. The
validation is done only to create default child nodes (due to
how libyang works) and any possible error is ignored (candidate
configurations can be invalid/incomplete).
The problem is that we were calling lyd_validate() only when the
CLI "with-defaults" option was used. But some cli_show() callbacks
assume that default nodes exist and can crash when displaying a
candidate configuration that isn't validated. To fix this, call
lyd_validate() before displaying candidate configuration even when
"with-defaults" is not used (that was a micro-optimization that
shouldn't have been done).
Signed-off-by: Renato Westphal <renato@opensourcerouting.org>
The previous workaround only works for -O0, at higher optimization
levels gcc reorders the statements in the file global scope which breaks
the asm statement :(.
Fixes: #4563Fixes: #5074
Signed-off-by: David Lamparter <equinox@diac24.net>
gcc 4.x does not properly support structs with variable length array
members. Specifically, for global variables, it completely ignores the
array, coming up with a size much smaller than what is correct. This is
broken for both sizeof() as well as ELF object size.
This breaks for frr_interface_info since this variable is in some cases
copy relocated by the linker. (The linker does this to make the address
of the variable a "constant" for the main program.) This copying uses
the ELF object size, thereby copying only the non-array part of the
struct.
Breakage ensues...
(This fix is a bit ugly, but it's limited to very old gcc, and it's
better than changing the array to "nodes[1000]" and wasting memory...)
Fixes: #4563Fixes: #5074
Signed-off-by: David Lamparter <equinox@diac24.net>
Add some apis that allocate and init nexthop objects
from various kinds of arguments: ip addrs, interfaces,
blackhole types.
Signed-off-by: Mark Stapp <mjs@voltanet.io>
By default announct Self Type-2 routes with
system IP as nexthop and system MAC as
nexthop.
An API to check type-2 is self route via
checking ipv4/ipv6 address from connected interfaces list.
An API to extract RMAC and nexthop for type-2
routes based on advertise-svi-ip knob is enabled.
When advertise-pip is enabled/disabled, trigger type-2
route update. For self type-2 routes to use
anycast or individual (rmac, nexthop) addresses.
Ticket:CM-26190
Reviewed By:
Testing Done:
Enable 'advertise-svi-ip' knob in bgp default instance.
the vrf instance svi ip is advertised with nexthop
as default instance router-id and RMAC as system MAC.
Signed-off-by: Chirag Shah <chirag@cumulusnetworks.com>
some vty no operations were not removing the entry of the access-list,
since the access-list name was not retrieved correctly. the index was
not correct for 'no ipv6 access-list WORD' operations, but also for one 'no
access-list WORD [..] any' operation.
PR=66244
Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>
Acked-by: Alain Ritoux <alain.ritoux@6wind.com>
This includes:
1. Processing client Registrations for MLAG
2. storing client Interests for MLAG updates
3. Opening communication channel to MLAG with First client reg
4. Closing Communication channel with last client De-reg
5. Spawning a new thread for handling MLAG updates peocessing
6. adding Test code
7. advertising MLAG Updates to clients based on their interests
Signed-off-by: Satheesh Kumar K <sathk@cumulusnetworks.com>
This includes:
1. Defining message formats
2. Stream Decoding after receiving the message at PIM
3. Handling MLAG UP & Down Notifications
Signed-off-by: Satheesh Kumar K <sathk@cumulusnetworks.com>
when ever a FRR Client wants to send any data to another node
using MLAG Channel, uses below mechanisam.
1. sends a MLAG Registration to zebra with interested messages that
it is intended to receive from peer.
2. In response to this request, Zebra opens communication channel with
MLAG. and also in Rx. diretion zebra forwards only those messages which
client shown interest during registration
3. when client is no-longer interested in communicating with MLAG, client
posts De-register to Zebra
4. if this is the last client which is interested for MLAG Communication,
zebra closes the channel.
why PIM Needs MLAG Communication
================================
1. In general on LAN Networks elecetd DR will send the Join towards
Multicast RP in case of a LHR and Register in case of FHR.
2. But in case DR Goes down, traffic will be re-converged only after
the New DR is elected, but this can take time based on Hold Timer to
detect the DR down.
3. this can be optimised by using MLAG Mecganisam.
4. and also Traffic can be forwarded more efficiently by knowing the cost
towards RP using MLAG
Signed-off-by: Satheesh Kumar K <sathk@cumulusnetworks.com>
This allows to set motd from an input instead of creating a file.
Example:
root@exit2-debian-9:~/frr# telnet 127.0.0.1 2605
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
Hello, this is bgpd
User Access Verification
Password:
exit2-debian-9> enable
exit2-debian-9# sh run
Current configuration:
!
frr version 7.3-dev-MyOwnFRRVersion
frr defaults traditional
!
hostname exit2-debian-9
password belekas
log file /var/log/frr/labas.log
log syslog informational
banner motd line Hello, this is bgpd
!
!
!
line vty
!
end
exit2-debian-9#
Signed-off-by: Donatas Abraitis <donatas.abraitis@gmail.com>
Scenarios where this code change is required:
1. BFD is un-configured from BGP at remote end.
Neighbour BFD sends ADMIN_DOWN state, but BFD on local side will send
DOWN to BGP, resulting in BGP session DOWN.
Removing BFD session administratively shouldn't bring DOWN BGP session
at local or remote.
2. BFD is un-configured from BGP or shutdown locally.
BFD will send state DOWN to BGP resulting in BGP session DOWN.
(This is akin to saying do not use BFD for BGP)
Removing BFD session administratively shouldn't bring DOWN BGP session at
local or remote.
Signed-off-by: Sayed Mohd Saquib sayed.saquib@broadcom.com
Make nexthop_next() and nexthop_next_active_resolved() use
const for the nexthop argument. They should not be modifying so
it makes sense here.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Reduce the api for deleting nexthops and the containing
group to just one call rather than having a special case
and handling it separately.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Add a common handler function for the different nexthop_group_equal*()
comparison functions.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Add NULL checks in `nexthop_group_equal*()` iteration
before calling `nexthop_same()` to make Clang SA happy.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Logic error on the second null check for nexthop groups
passed to the `nexthop_group_equal*() functions. This fixes it.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Add a nexthop hashing api for only hashing on word-sized
attributes. Calling the jhash/jhash2 function is quite slow
in scaled envrionments but sometimes you do need a more granular hash.
The tradeoff here is that hashtable buckets using this hash
might be more full.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
In the nexthop hashing function, lets reduce the hash calls as
much as possible. So, reduce the onlink and infindex to one
call to jhash_2words().
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Optimize the fib and notified nexthop group comparison algorithm
to assume ordering. There were some pretty serious performance hits with
this on high ecmp routes.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Separate nexthop_group_equal() into two versions. One
that compares verses recurisvely resolved nexthops and
one that doesn't.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
We were waiting until install time to mark nexthops as duplicate.
Since they are immutable now and re-used, move this marking into
when they are actually created to save a bunch of cycles.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
When hashing a nexthop, shove all the nexthop g_addr data together
and pass it as one call to jhash2() to optimize a bit better.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Speed up nexthop_group_equal() by making it assume the
groups it has been passed are ordered. This should always
be the case.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
We should hash nexthops on the onlink flag since that is a
descriptor of the nexthop and not a status of it.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Include resolved nexthops when hashing a nexthop
group but provide an API that allows you to non-recursively
hash as well.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Add the ability to recursively resolve nexthop group hash entries
and resolve them when sending to the kernel.
When copying over nexthops into an NHE, copy resolved info as well.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
We will use a nhe context for dataplane interaction with
nextho group hash entries.
New nhe's from the kernel will be put into a group array
if they are a group and queued on the rib metaq to be processed
later.
New nhe's sent to the kernel will be set on the dataplane context
with approprate ID's in the group array if needed.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
Add a function to check whether nexthop groups
are equivalent. It does not care about ordering.
Also, set any functions that it relies on to take
const vars as well.
Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com>
