matthieu/frr
1
0
Fork 0
forked from Mirror/frr
Code Pull requests Activity

zebra: modify fpm_listener to display data about nhgs

Browse source 
Currently the fpm_listener completely ignores NHG's.
Let's start dumping some data about the nexthop groups:

[2025-04-10 16:55:12.939235306] FPM message - Type: 1, Length 52
[2025-04-10 16:55:12.939254252] Nexthop Group ID: 9, Protocol: Zebra(11), Contains 1 nexthops, Family: 2, Scope: 0
[2025-04-10 16:55:12.939260564] FPM message - Type: 1, Length 52
[2025-04-10 16:55:12.939263990] Nexthop Group ID: 10, Protocol: Zebra(11), Contains 1 nexthops, Family: 2, Scope: 0
[2025-04-10 16:55:12.939268659] FPM message - Type: 1, Length 56
[2025-04-10 16:55:12.939271635] Nexthop Group ID: 8, Protocol: Zebra(11), Contains 2 nexthops, Family: 0, Scope: 0

Signed-off-by: Donald Sharp <sharpd@nvidia.com>
This commit is contained in:
Donald Sharp 2025-04-10 16:57:10 -04:00
parent dc37bff8c0
commit ef580f0e80
1 changed files with 68 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

68
zebra/fpm_listener.c
View file

@ -33,10 +33,12 @@
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/if_link.h>
#include <linux/nexthop.h>
#include "rt_netlink.h"
#include "fpm/fpm.h"
#include "lib/libfrr.h"
#include "zebra/kernel_netlink.h"
XREF_SETUP();
@ -572,6 +574,67 @@ static int parse_route_msg(struct netlink_msg_ctx *ctx)
return 1;
}
/*
* parse_nexthop_msg
*/
static int parse_nexthop_msg(struct nlmsghdr *hdr)
{
struct nhmsg *nhmsg;
struct rtattr *tb[NHA_MAX + 1] = {};
int len;
uint32_t nhgid = 0;
uint8_t nhg_count = 0;
const char *err_msg = NULL;
char protocol_str[32] = "Unknown";
nhmsg = NLMSG_DATA(hdr);
len = hdr->nlmsg_len - NLMSG_LENGTH(sizeof(*nhmsg));
if (len < 0) {
fprintf(stderr, "Bad nexthop message length\n");
return 0;
}
if (!parse_rtattrs_(RTM_NHA(nhmsg), len, tb, ARRAY_SIZE(tb), &err_msg)) {
fprintf(stderr, "Error parsing nexthop attributes: %s\n", err_msg);
return 0;
}
/* Get protocol string */
snprintf(protocol_str, sizeof(protocol_str), "%s(%u)",
netlink_prot_to_s(nhmsg->nh_protocol), nhmsg->nh_protocol);
/* Get Nexthop Group ID */
if (tb[NHA_ID])
nhgid = *(uint32_t *)RTA_DATA(tb[NHA_ID]);
/* Count nexthops in the group */
if (tb[NHA_GROUP]) {
struct nexthop_grp *nhg = (struct nexthop_grp *)RTA_DATA(tb[NHA_GROUP]);
size_t count = (RTA_PAYLOAD(tb[NHA_GROUP]) / sizeof(*nhg));
if (count > 0 && (count * sizeof(*nhg)) == RTA_PAYLOAD(tb[NHA_GROUP]))
nhg_count = count;
} else if (tb[NHA_OIF] || tb[NHA_GATEWAY]) {
/* Single nexthop case */
nhg_count = 1;
}
/* Print blackhole status if applicable */
if (tb[NHA_BLACKHOLE]) {
fprintf(glob->output_file,
"[%s] %s Nexthop Group ID: %u, Protocol: %s, Type: BLACKHOLE, Family: %u\n",
get_timestamp(), hdr->nlmsg_type == RTM_NEWNEXTHOP ? "New" : "Del", nhgid,
protocol_str, nhmsg->nh_family);
} else {
fprintf(glob->output_file,
"[%s] %s Nexthop Group ID: %u, Protocol: %s, Contains %u nexthops, Family: %u, Scope: %u\n",
get_timestamp(), hdr->nlmsg_type == RTM_NEWNEXTHOP ? "New" : "Del", nhgid,
protocol_str, nhg_count, nhmsg->nh_family, nhmsg->nh_scope);
}
return 1;
}
/*
* addr_to_s
*/
@ -742,6 +805,11 @@ static void parse_netlink_msg(char *buf, size_t buf_len, fpm_msg_hdr_t *fpm)
}
break;
case RTM_NEWNEXTHOP:
case RTM_DELNEXTHOP:
parse_nexthop_msg(hdr);
break;
default:
fprintf(glob->output_file, "[%s] Ignoring netlink message - Type: %s(%d)\n",
get_timestamp(), netlink_msg_type_to_s(hdr->nlmsg_type),