stp: integrate 802.1D Spanning Tree Protocol into BridgeDevice

Adds loop prevention to Ethernet bridges:
- BridgeDevice gains stp: Option<StpState> field
- enable_stp(priority, mac) method initializes STP per-bridge
- BPDU frames (dst 01:80:c2:00:00:00) intercepted in recv(),
  processed locally, never forwarded
- STP hello timer sends periodic BPDUs on all ports (root bridge)
- flood() skips STP-blocked ports
- build_bpdu() made public for bridge integration
- stp module declared in link/mod.rs

The recv() flow now: age MACs → check STP hello timer →
poll ports → detect BPDU (absorb) → normal frame (learn + forward).

Reference: Linux 7.1 net/bridge/br_stp.c, br_stp_bpdu.c, br_stp_timer.c

This commit is contained in:

Red Bear OS

2026-07-08 13:38:38 +03:00

parent 1606a6ffb2

commit 30db94c970

4 changed files with 63 additions and 23 deletions

									
										netstack/src/link/mod.rs
									
		+1
		
												View File
												
				@@ -5,6 +5,7 @@ pub mod gre;

				pub mod ipip;

				pub mod loopback;

				pub mod qdisc;

				pub mod stp;

				pub mod tun;

				pub mod vlan;

				pub mod vxlan;