Nhrp maintain used state

[pguibert6WIND]

The problem is due to the 'U'sed flag of dynamic cache entries (shortcut), which is set to false, despite its use. Consequently, the shortcut associated goes in expiring state.

Fix this by ensuring that the 'U'sed flag is properly set to true, as it is always maintained by NHRP. Only NHRP can decide whether the cache entry is valid or not.

2023/11/06 11:25:16 NHRP: [KHACV-6YE92] Send Resolution-Request(1) 11.255.255.2 -> 11.255.255.4
2023/11/06 11:25:16 NHRP: [WSA6E-5GM0H] PACKET: Send 10.125.0.2 -> 10.125.0.4
2023/11/06 11:25:16 NHRP: [K0534-5VD2M] PACKET: Recv 10.125.0.4 -> 10.125.0.2
2023/11/06 11:25:16 NHRP: [KHACV-6YE92] Recv Resolution-Reply(2) 11.255.255.4 -> 11.255.255.2
2023/11/06 11:25:16 NHRP: [KHACV-6YE92] !LOCAL Resolution-Reply(2) 11.255.255.4 -> 11.255.255.2
2023/11/06 11:25:16 NHRP: [KZFC5-JYQF6] Shortcut: 11.255.255.4/32 is at proto 11.255.255.4 dst_proto 11.255.255.4 NBMA 10.125.0.4 cie-holdtime 1200
2023/11/06 11:25:16 NHRP: [J0Y1F-TGYD3] Shortcut: cache found, update binding
2023/11/06 11:25:16 NHRP: [VZQX2-A5SP9] cache: same type 4, updating expiry and changing nbma addr from 10.125.0.4 to 10.125.0.4
2023/11/06 11:25:16 NHRP: [MWP37-NGEEE] Shortcut: calling update_binding
2023/11/06 11:25:16 NHRP: [TP7X1-TKH88] Shortcut: Resolution reply handled

[pguibert6WIND]

The problem is due to the 'U'sed flag of dynamic cache entries (shortcut), which is set to false, despite its use. Consequently, the shortcut associated goes in expiring state.

Fix this by ensuring that the 'U'sed flag is properly set to true, as it is always maintained by NHRP. Only NHRP can decide whether the cache entry is valid or not.

2023/11/06 11:25:16 NHRP: [KHACV-6YE92] Send Resolution-Request(1) 11.255.255.2 -> 11.255.255.4
2023/11/06 11:25:16 NHRP: [WSA6E-5GM0H] PACKET: Send 10.125.0.2 -> 10.125.0.4
2023/11/06 11:25:16 NHRP: [K0534-5VD2M] PACKET: Recv 10.125.0.4 -> 10.125.0.2
2023/11/06 11:25:16 NHRP: [KHACV-6YE92] Recv Resolution-Reply(2) 11.255.255.4 -> 11.255.255.2
2023/11/06 11:25:16 NHRP: [KHACV-6YE92] !LOCAL Resolution-Reply(2) 11.255.255.4 -> 11.255.255.2
2023/11/06 11:25:16 NHRP: [KZFC5-JYQF6] Shortcut: 11.255.255.4/32 is at proto 11.255.255.4 dst_proto 11.255.255.4 NBMA 10.125.0.4 cie-holdtime 1200
2023/11/06 11:25:16 NHRP: [J0Y1F-TGYD3] Shortcut: cache found, update binding
2023/11/06 11:25:16 NHRP: [VZQX2-A5SP9] cache: same type 4, updating expiry and changing nbma addr from 10.125.0.4 to 10.125.0.4
2023/11/06 11:25:16 NHRP: [MWP37-NGEEE] Shortcut: calling update_binding
2023/11/06 11:25:16 NHRP: [TP7X1-TKH88] Shortcut: Resolution reply handled

The main fix is simpler, as it modified the netlink filter so that we are now able to receive NEWNEIGH notifications.

[pguibert6WIND]

ci:rerun

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