The ARP table that is dumped when the xdp_router_ipv4 process is launched
has the IP address & MAC address in non-readable network byte order format,
also the alignment is off when printing the table.
Address HwAddress
160000e0 1600005e0001
ff96a8c0 ffffffffffff
faffffef faff7f5e0001
196a8c0 9607871293ea
fb0000e0 fb00005e0001
0 0
196a8c0 9607871293ea
ffff11ac ffffffffffff
faffffef faff7f5e0001
fb0000e0 fb00005e0001
160000e0 1600005e0001
160000e0 1600005e0001
faffffef faff7f5e0001
fb0000e0 fb00005e0001
40011ac 40011ac4202
Fix this by converting the "Address" field from network byte order Hex into
dotted decimal notation IPv4 format and "HwAddress" field from network byte
order Hex into Colon separated Hex format. Also fix the aligntment of the
fields in the ARP table.
Address HwAddress
224.0.0.22 01:00:5e:00:00:16
192.168.150.255 ff:ff:ff:ff:ff:ff
239.255.255.250 01:00:5e:7f:ff:fa
192.168.150.1 ea:93:12:87:07:96
224.0.0.251 01:00:5e:00:00:fb
0.0.0.0 00:00:00:00:00:00
192.168.150.1 ea:93:12:87:07:96
172.17.255.255 ff:ff:ff:ff:ff:ff
239.255.255.250 01:00:5e:7f:ff:fa
224.0.0.251 01:00:5e:00:00:fb
224.0.0.22 01:00:5e:00:00:16
224.0.0.22 01:00:5e:00:00:16
239.255.255.250 01:00:5e:7f:ff:fa
224.0.0.251 01:00:5e:00:00:fb
172.17.0.4 02:42:ac:11:00:04
Signed-off-by: Gokul Sivakumar <gokulkumar792@xxxxxxxxx>
---
samples/bpf/xdp_router_ipv4_user.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)
diff --git a/samples/bpf/xdp_router_ipv4_user.c b/samples/bpf/xdp_router_ipv4_user.c
index 3e9db5a8c8c6..cfaf7e50e431 100644
--- a/samples/bpf/xdp_router_ipv4_user.c
+++ b/samples/bpf/xdp_router_ipv4_user.c
@@ -397,8 +397,12 @@ static void read_arp(struct nlmsghdr *nh, int nll)
if (nh->nlmsg_type == RTM_GETNEIGH)
printf("READING arp entry\n");
- printf("Address\tHwAddress\n");
+ printf("Address HwAddress\n");
for (; NLMSG_OK(nh, nll); nh = NLMSG_NEXT(nh, nll)) {
+ struct in_addr dst_addr;
+ char mac_str[18];
+ int len = 0, i;
+
rt_msg = (struct ndmsg *)NLMSG_DATA(nh);
rt_attr = (struct rtattr *)RTM_RTA(rt_msg);
ndm_family = rt_msg->ndm_family;
@@ -419,7 +423,14 @@ static void read_arp(struct nlmsghdr *nh, int nll)
}
arp_entry.dst = atoi(dsts);
arp_entry.mac = atol(mac);
- printf("%x\t\t%llx\n", arp_entry.dst, arp_entry.mac);
+
+ dst_addr.s_addr = arp_entry.dst;
+ for (i = 0; i < 6; i++)
+ len += snprintf(mac_str + len, 18 - len, "%02llx%s",
+ ((arp_entry.mac >> i * 8) & 0xff),
+ i < 5 ? ":" : "");
+ printf("%-16s%s\n", inet_ntoa(dst_addr), mac_str);
+
if (ndm_family == AF_INET) {
if (bpf_map_lookup_elem(exact_match_map_fd,
&arp_entry.dst,
@@ -728,7 +739,7 @@ int main(int ac, char **argv)
printf("\n*******************ROUTE TABLE*************************\n");
get_route_table(AF_INET);
- printf("*******************ARP TABLE***************************\n\n\n");
+ printf("\n*******************ARP TABLE***************************\n");
get_arp_table(AF_INET);
if (monitor_route() < 0) {
printf("Error in receiving route update");
--
2.25.1
