OCPBUGS-10695: Ignore IPv4-mapped-on-IPv6 addresses from bind test

When dealing with IPv6 addresses we need to make sure they are bindable
before we report network as ready. The check has been introduced in
openshift#3362 and works
by trying to simply bind to a specified IPv6 address.

The check however doesn't account for the fact that we may have
addresses in the form of IPv4-mapped-on-IPv6. In such a scenario ncat is
returning an "Invalid argument" error because it tries to open a socket
of type `AF_INET6` whereas this type of address requires additional
`IPV6_ADDRFORM` option which ncat is not setting. Another possibility is
to create a socket of type `AF_INET` what could be done by

```
nc -4 -l ::ffff:192.168.0.14 53604
```

In order to workaround this behaviour of netcat, we are ignoring the
bind tests for IPv4-mapped-on-IPv6 address, as due to its nature it will
never be stuck in tentative state even when rest of the infrastrucure is
performing Duplicate Address Detection. As this address belongs to a
special class of addresses, we can afford its special handling.

Closes: OCPBUGS-10695

templates/common/_base/files/configure-ovs-network.yaml

@@ -13,7 +13,7 @@ contents:
     NM_CONN_ETC_PATH="/etc/NetworkManager/system-connections"
     NM_CONN_RUN_PATH="/run/NetworkManager/system-connections"
 
-    # This is the path where NM is known to be configured to store user keyfiles 
+    # This is the path where NM is known to be configured to store user keyfiles
     NM_CONN_CONF_PATH="$NM_CONN_ETC_PATH"
     # This is where we want our keyfiles to finally reside
     NM_CONN_SET_PATH="${NM_CONN_SET_PATH:-$NM_CONN_RUN_PATH}"
@@ -263,8 +263,8 @@ contents:
         # br-ex has a different mac address than the bond which might be
         # troublesome on some platforms where the nic won't accept packets with
         # a different destination mac. But nobody has complained so far so go on
-        # with what we got. 
-        
+        # with what we got.
+
         # Do set it though for other link aggregation configurations where the
         # mac address would otherwise depend on enslave order for which we have
         # no control going forward.
@@ -391,10 +391,10 @@ contents:
     # Removes any previous ovs configuration
     remove_all_ovn_bridges() {
       echo "Reverting any previous OVS configuration"
-      
+
       remove_ovn_bridges br-ex phys0
       remove_ovn_bridges br-ex1 phys1
-      
+
       echo "OVS configuration successfully reverted"
     }
 
@@ -421,10 +421,10 @@ contents:
         # Only attempt to connect a disconnected device
         local connected_state=$(nmcli -g GENERAL.STATE device show "$dev" || echo "")
         if [[ "$connected_state" =~ "disconnected" ]]; then
-          # keep track if a profile by the same name as the device existed 
+          # keep track if a profile by the same name as the device existed
           # before we attempt activation
           local named_profile_existed=$([ -f "${NM_CONN_CONF_PATH}/${dev}" ] || [ -f "${NM_CONN_CONF_PATH}/${dev}.nmconnection" ] && echo "yes")
-          
+
           for i in {1..10}; do
               echo "Attempt $i to connect device $dev"
               nmcli device connect "$dev" && break
@@ -455,10 +455,10 @@ contents:
     rollback_nm() {
       phys0=$(get_bridge_physical_interface ovs-if-phys0)
       phys1=$(get_bridge_physical_interface ovs-if-phys1)
-      
+
       # Revert changes made by /usr/local/bin/configure-ovs.sh during SDN migration.
       remove_all_ovn_bridges
-      
+
       # reload profiles so that NM notices that some were removed
       reload_profiles_nm "$phys0" "$phys1"
     }
@@ -500,7 +500,7 @@ contents:
         local is_slave=false
         if [ "$slave_type" = "team" ] || [ "$slave_type" = "bond" ]; then
           is_slave=true
-        fi 
+        fi
 
         # For slave interfaces, initialize the master interface to false if the key is not yet in the array
         local master_interface
@@ -589,7 +589,10 @@ contents:
 
     # This function waits for ip address of br-ex to be bindable only in case of ipv6
     # This is workaround for OCPBUGS-673 as it will not allow starting crio
-    # before address is bindable
+    # before address is bindable.
+    # Because IPv4-mapped-on-IPv6 addresses are not usable as simple AF_INET6 sockets
+    # but either as AF_INET or AF_INET6 with additional IPV6_ADDRFORM option, we are
+    # ignoring them from the test.
     try_to_bind_ipv6_address() {
       # Retry for 1 minute
       retries=60
@@ -598,6 +601,8 @@ contents:
         if [[ "${ip}" == "" ]]; then
           echo "No ipv6 ip to bind was found"
           break
+        elif [[ "${ip}" = ::ffff* ]]; then
+          echo "IPv4-mapped-on-IPv6 address detected; ignoring binding test"
         fi
         random_port=$(shuf -i 50000-60000 -n 1)
         echo "Trying to bind ${ip} on port ${random_port}"
@@ -750,7 +755,7 @@ contents:
     handle_exit() {
       e=$?
       tdir=$(mktemp -u -d -t "configure-ovs-$(date +%Y-%m-%d-%H-%M-%S)-XXXXXXXXXX")
-      
+
       if [ $e -eq 0 ]; then
         print_state
         # remove previous troubleshooting information
@@ -936,7 +941,7 @@ contents:
       elif [ "$1" == "OpenShiftSDN" ]; then
         # Revert changes made by /usr/local/bin/configure-ovs.sh during SDN migration.
         rollback_nm
-        
+
         # Remove bridges created by ovn-kubernetes
         ovs-vsctl --timeout=30 --if-exists del-br br-int -- --if-exists del-br br-local
       fi