Add option to ignore duplicate bridge use detection

pkg/plugin/network.go

@@ -50,52 +50,54 @@ func (p *Plugin) CreateNetwork(r CreateNetworkRequest) error {
 		return util.ErrNotBridge
 	}
 
-	v4Addrs, err := netlink.AddrList(link, unix.AF_INET)
-	if err != nil {
-		return fmt.Errorf("failed to retrieve IPv4 addresses for %v: %w", opts.Bridge, err)
-	}
-	v6Addrs, err := netlink.AddrList(link, unix.AF_INET6)
-	if err != nil {
-		return fmt.Errorf("failed to retrieve IPv6 addresses for %v: %w", opts.Bridge, err)
-	}
-	bridgeAddrs := append(v4Addrs, v6Addrs...)
-
-	nets, err := p.docker.NetworkList(context.Background(), dTypes.NetworkListOptions{})
-	if err != nil {
-		return fmt.Errorf("failed to retrieve list of networks from Docker: %w", err)
-	}
-
-	// Make sure the addresses on this bridge aren't used by another network
-	for _, n := range nets {
-		if IsDHCPPlugin(n.Driver) {
-			otherOpts, err := decodeOpts(n.Options)
-			if err != nil {
-				log.
-					WithField("network", n.Name).
-					WithError(err).
-					Warn("Failed to parse other DHCP network's options")
-			} else if otherOpts.Bridge == opts.Bridge {
-				return util.ErrBridgeUsed
-			}
+	if !opts.IgnoreConflicts {
+		v4Addrs, err := netlink.AddrList(link, unix.AF_INET)
+		if err != nil {
+			return fmt.Errorf("failed to retrieve IPv4 addresses for %v: %w", opts.Bridge, err)
 		}
-		if n.IPAM.Driver == "null" {
-			// Null driver networks will have 0.0.0.0/0 which covers any address range!
-			continue
+		v6Addrs, err := netlink.AddrList(link, unix.AF_INET6)
+		if err != nil {
+			return fmt.Errorf("failed to retrieve IPv6 addresses for %v: %w", opts.Bridge, err)
 		}
+		bridgeAddrs := append(v4Addrs, v6Addrs...)
 
-		for _, c := range n.IPAM.Config {
-			_, dockerCIDR, err := net.ParseCIDR(c.Subnet)
-			if err != nil {
-				return fmt.Errorf("failed to parse subnet %v on Docker network %v: %w", c.Subnet, n.ID, err)
+		nets, err := p.docker.NetworkList(context.Background(), dTypes.NetworkListOptions{})
+		if err != nil {
+			return fmt.Errorf("failed to retrieve list of networks from Docker: %w", err)
+		}
+
+		// Make sure the addresses on this bridge aren't used by another network
+		for _, n := range nets {
+			if IsDHCPPlugin(n.Driver) {
+				otherOpts, err := decodeOpts(n.Options)
+				if err != nil {
+					log.
+						WithField("network", n.Name).
+						WithError(err).
+						Warn("Failed to parse other DHCP network's options")
+				} else if otherOpts.Bridge == opts.Bridge {
+					return util.ErrBridgeUsed
+				}
 			}
-			if bytes.Equal(dockerCIDR.Mask, net.CIDRMask(0, 32)) || bytes.Equal(dockerCIDR.Mask, net.CIDRMask(0, 128)) {
-				// Last check to make sure the network isn't 0.0.0.0/0 or ::/0 (which would always pass the check below)
+			if n.IPAM.Driver == "null" {
+				// Null driver networks will have 0.0.0.0/0 which covers any address range!
 				continue
 			}
 
-			for _, bridgeAddr := range bridgeAddrs {
-				if bridgeAddr.IPNet.Contains(dockerCIDR.IP) || dockerCIDR.Contains(bridgeAddr.IP) {
-					return util.ErrBridgeUsed
+			for _, c := range n.IPAM.Config {
+				_, dockerCIDR, err := net.ParseCIDR(c.Subnet)
+				if err != nil {
+					return fmt.Errorf("failed to parse subnet %v on Docker network %v: %w", c.Subnet, n.ID, err)
+				}
+				if bytes.Equal(dockerCIDR.Mask, net.CIDRMask(0, 32)) || bytes.Equal(dockerCIDR.Mask, net.CIDRMask(0, 128)) {
+					// Last check to make sure the network isn't 0.0.0.0/0 or ::/0 (which would always pass the check below)
+					continue
+				}
+
+				for _, bridgeAddr := range bridgeAddrs {
+					if bridgeAddr.IPNet.Contains(dockerCIDR.IP) || dockerCIDR.Contains(bridgeAddr.IP) {
+						return util.ErrBridgeUsed
+					}
 				}
 			}
 		}

pkg/plugin/plugin.go

@@ -29,9 +29,10 @@ func IsDHCPPlugin(driver string) bool {
 
 // DHCPNetworkOptions contains options for the DHCP network driver
 type DHCPNetworkOptions struct {
-	Bridge       string
-	IPv6         bool
-	LeaseTimeout time.Duration `mapstructure:"lease_timeout"`
+	Bridge          string
+	IPv6            bool
+	LeaseTimeout    time.Duration `mapstructure:"lease_timeout"`
+	IgnoreConflicts bool          `mapstructure:"ignore_conflicts"`
 }
 
 func decodeOpts(input interface{}) (DHCPNetworkOptions, error) {