feat: add support for --iface-regex match interface with multi IP addresses

[ttys3]

Description

resolve #981

if interface has multi IPs, current match implementation will failed to get the right IP.

for example, interface dummy0 has 4 IPs:

1.10.100.1
192.168.200.128
172.16.30.18
172.16.31.200

we expect to use 192\.168\.200\.\d+ as --iface-regex option to get 192.168.200.128 matched.

Todos

• Tests
• Documentation
• Release note

Release Note

None required

[luthermonson]

@ttys3 have you tested this on a real environment and does it fix your issues? we're ready to merge as it looks good but want to confirm

[ttys3]

@luthermonson yes, I just tested it on a new created Linux node. It works.

/etc/systemd/system/flanneld.service

[Service]
Environment=FLANNELD_IFACE_REGEX=192\\.168\\.\\d+\\.\\d+

The interface is eth0 and it has 2 ipv4 ips (one public IP and one LAN) and 2 ipv6 ips.

Feb 17 18:17:02  flanneld[41261]: I0217 18:17:02.554665   41261 main.go:226] Created subnet manager: Etcd Local Manager with Previous Subnet: None
Feb 17 18:17:02  flanneld[41261]: I0217 18:17:02.554687   41261 main.go:229] Installing signal handlers
Feb 17 18:17:02  flanneld[41261]: I0217 18:17:02.558901   41261 main.go:550] Start healthz server on 0.0.0.0:8072
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.569659   41261 main.go:453] Found network config - Backend type: vxlan
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.571698   41261 match.go:228] Using interface with name eth0 and address 192.168.138.76
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.571845   41261 match.go:250] Defaulting external address to interface address (192.168.138.76)
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.571955   41261 match.go:263] Defaulting external v6 address to interface address (<nil>)
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.572153   41261 vxlan.go:138] VXLAN config: VNI=1 Port=0 GBP=false Learning=false DirectRouting=false
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.625600   41261 local_manager.go:237] Picking subnet in range 10.5.1.0 ... 10.5.255.0
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.634146   41261 local_manager.go:223] Allocated lease (10.5.32.0/24) to current node (192.168.138.76)
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.634585   41261 main.go:402] Current network or subnet (10.5.0.0/16, 10.5.32.0/24) is not equal to previous one (0.0.0.0/0, 0.0.0.0/0), tryin>
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.654269   41261 iptables.go:241] Deleting iptables rule: -s 0.0.0.0/0 -d 0.0.0.0/0 -m comment --comment flanneld masq -j RETURN
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.730145   41261 iptables.go:241] Deleting iptables rule: -s 0.0.0.0/0 ! -d 224.0.0.0/4 -m comment --comment flannel masq -j MASQUERADE --rand>
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.750423   41261 iptables.go:241] Deleting iptables rule: ! -s 0.0.0.0/0 -d 0.0.0.0/0 -m comment --comment flanneld masq -j RETURN
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.753980   41261 iptables.go:241] Deleting iptables rule: ! -s 0.0.0.0/0 -d 0.0.0.0/0 -m comment --comment flanneld masq -j MASQUERADE --rando>
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.766815   41261 main.go:334] Setting up masking rules
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.774181   41261 main.go:355] Changing default FORWARD chain policy to ACCEPT
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.774654   41261 main.go:368] Wrote subnet file to /run/flannel/subnet.env
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.775982   41261 main.go:372] Running backend.
Feb 17 18:17:03  systemd[1]: Started FlannelD Network fabric for containers.
Feb 17 18:17:03  flanneld[41261]: I0217 18:17:03.788493   41261 vxlan_network.go:61] watching for new subnet leases

[ttys3]

@luthermonson PTAL, the CI need approve again

[manuelbuil]

Could you please rebase? There is a new test in CI (golangci-lint)

[ttys3]

Could you please rebase? There is a new test in CI (golangci-lint)

rebased, PTAL @manuelbuil @luthermonson

[manuelbuil]

@ttys3 could you resolve the conflict please? After that I'll merge the PR. Sorry for the delay!

[ttys3]

@manuelbuil rebased. PTAL