diff options
Diffstat (limited to 'vendor/k8s.io/apimachinery/pkg/util/net/interface.go')
| -rw-r--r-- | vendor/k8s.io/apimachinery/pkg/util/net/interface.go | 499 |
1 files changed, 0 insertions, 499 deletions
diff --git a/vendor/k8s.io/apimachinery/pkg/util/net/interface.go b/vendor/k8s.io/apimachinery/pkg/util/net/interface.go deleted file mode 100644 index 9adf4cfe4..000000000 --- a/vendor/k8s.io/apimachinery/pkg/util/net/interface.go +++ /dev/null @@ -1,499 +0,0 @@ -/* -Copyright 2016 The Kubernetes Authors. - -Licensed under the Apache License, Version 2.0 (the "License"); -you may not use this file except in compliance with the License. -You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - -Unless required by applicable law or agreed to in writing, software -distributed under the License is distributed on an "AS IS" BASIS, -WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -See the License for the specific language governing permissions and -limitations under the License. -*/ - -package net - -import ( - "bufio" - "encoding/hex" - "fmt" - "io" - "net" - "os" - - "strings" - - "k8s.io/klog/v2" -) - -type AddressFamily uint - -const ( - familyIPv4 AddressFamily = 4 - familyIPv6 AddressFamily = 6 -) - -type AddressFamilyPreference []AddressFamily - -var ( - preferIPv4 = AddressFamilyPreference{familyIPv4, familyIPv6} - preferIPv6 = AddressFamilyPreference{familyIPv6, familyIPv4} -) - -const ( - // LoopbackInterfaceName is the default name of the loopback interface - LoopbackInterfaceName = "lo" -) - -const ( - ipv4RouteFile = "/proc/net/route" - ipv6RouteFile = "/proc/net/ipv6_route" -) - -type Route struct { - Interface string - Destination net.IP - Gateway net.IP - Family AddressFamily -} - -type RouteFile struct { - name string - parse func(input io.Reader) ([]Route, error) -} - -// noRoutesError can be returned in case of no routes -type noRoutesError struct { - message string -} - -func (e noRoutesError) Error() string { - return e.message -} - -// IsNoRoutesError checks if an error is of type noRoutesError -func IsNoRoutesError(err error) bool { - if err == nil { - return false - } - switch err.(type) { - case noRoutesError: - return true - default: - return false - } -} - -var ( - v4File = RouteFile{name: ipv4RouteFile, parse: getIPv4DefaultRoutes} - v6File = RouteFile{name: ipv6RouteFile, parse: getIPv6DefaultRoutes} -) - -func (rf RouteFile) extract() ([]Route, error) { - file, err := os.Open(rf.name) - if err != nil { - return nil, err - } - defer file.Close() - return rf.parse(file) -} - -// getIPv4DefaultRoutes obtains the IPv4 routes, and filters out non-default routes. -func getIPv4DefaultRoutes(input io.Reader) ([]Route, error) { - routes := []Route{} - scanner := bufio.NewReader(input) - for { - line, err := scanner.ReadString('\n') - if err == io.EOF { - break - } - //ignore the headers in the route info - if strings.HasPrefix(line, "Iface") { - continue - } - fields := strings.Fields(line) - // Interested in fields: - // 0 - interface name - // 1 - destination address - // 2 - gateway - dest, err := parseIP(fields[1], familyIPv4) - if err != nil { - return nil, err - } - gw, err := parseIP(fields[2], familyIPv4) - if err != nil { - return nil, err - } - if !dest.Equal(net.IPv4zero) { - continue - } - routes = append(routes, Route{ - Interface: fields[0], - Destination: dest, - Gateway: gw, - Family: familyIPv4, - }) - } - return routes, nil -} - -func getIPv6DefaultRoutes(input io.Reader) ([]Route, error) { - routes := []Route{} - scanner := bufio.NewReader(input) - for { - line, err := scanner.ReadString('\n') - if err == io.EOF { - break - } - fields := strings.Fields(line) - // Interested in fields: - // 0 - destination address - // 4 - gateway - // 9 - interface name - dest, err := parseIP(fields[0], familyIPv6) - if err != nil { - return nil, err - } - gw, err := parseIP(fields[4], familyIPv6) - if err != nil { - return nil, err - } - if !dest.Equal(net.IPv6zero) { - continue - } - if gw.Equal(net.IPv6zero) { - continue // loopback - } - routes = append(routes, Route{ - Interface: fields[9], - Destination: dest, - Gateway: gw, - Family: familyIPv6, - }) - } - return routes, nil -} - -// parseIP takes the hex IP address string from route file and converts it -// to a net.IP address. For IPv4, the value must be converted to big endian. -func parseIP(str string, family AddressFamily) (net.IP, error) { - if str == "" { - return nil, fmt.Errorf("input is nil") - } - bytes, err := hex.DecodeString(str) - if err != nil { - return nil, err - } - if family == familyIPv4 { - if len(bytes) != net.IPv4len { - return nil, fmt.Errorf("invalid IPv4 address in route") - } - return net.IP([]byte{bytes[3], bytes[2], bytes[1], bytes[0]}), nil - } - // Must be IPv6 - if len(bytes) != net.IPv6len { - return nil, fmt.Errorf("invalid IPv6 address in route") - } - return net.IP(bytes), nil -} - -func isInterfaceUp(intf *net.Interface) bool { - if intf == nil { - return false - } - if intf.Flags&net.FlagUp != 0 { - klog.V(4).Infof("Interface %v is up", intf.Name) - return true - } - return false -} - -func isLoopbackOrPointToPoint(intf *net.Interface) bool { - return intf.Flags&(net.FlagLoopback|net.FlagPointToPoint) != 0 -} - -// getMatchingGlobalIP returns the first valid global unicast address of the given -// 'family' from the list of 'addrs'. -func getMatchingGlobalIP(addrs []net.Addr, family AddressFamily) (net.IP, error) { - if len(addrs) > 0 { - for i := range addrs { - klog.V(4).Infof("Checking addr %s.", addrs[i].String()) - ip, _, err := net.ParseCIDR(addrs[i].String()) - if err != nil { - return nil, err - } - if memberOf(ip, family) { - if ip.IsGlobalUnicast() { - klog.V(4).Infof("IP found %v", ip) - return ip, nil - } else { - klog.V(4).Infof("Non-global unicast address found %v", ip) - } - } else { - klog.V(4).Infof("%v is not an IPv%d address", ip, int(family)) - } - - } - } - return nil, nil -} - -// getIPFromInterface gets the IPs on an interface and returns a global unicast address, if any. The -// interface must be up, the IP must in the family requested, and the IP must be a global unicast address. -func getIPFromInterface(intfName string, forFamily AddressFamily, nw networkInterfacer) (net.IP, error) { - intf, err := nw.InterfaceByName(intfName) - if err != nil { - return nil, err - } - if isInterfaceUp(intf) { - addrs, err := nw.Addrs(intf) - if err != nil { - return nil, err - } - klog.V(4).Infof("Interface %q has %d addresses :%v.", intfName, len(addrs), addrs) - matchingIP, err := getMatchingGlobalIP(addrs, forFamily) - if err != nil { - return nil, err - } - if matchingIP != nil { - klog.V(4).Infof("Found valid IPv%d address %v for interface %q.", int(forFamily), matchingIP, intfName) - return matchingIP, nil - } - } - return nil, nil -} - -// getIPFromLoopbackInterface gets the IPs on a loopback interface and returns a global unicast address, if any. -// The loopback interface must be up, the IP must in the family requested, and the IP must be a global unicast address. -func getIPFromLoopbackInterface(forFamily AddressFamily, nw networkInterfacer) (net.IP, error) { - intfs, err := nw.Interfaces() - if err != nil { - return nil, err - } - for _, intf := range intfs { - if !isInterfaceUp(&intf) { - continue - } - if intf.Flags&(net.FlagLoopback) != 0 { - addrs, err := nw.Addrs(&intf) - if err != nil { - return nil, err - } - klog.V(4).Infof("Interface %q has %d addresses :%v.", intf.Name, len(addrs), addrs) - matchingIP, err := getMatchingGlobalIP(addrs, forFamily) - if err != nil { - return nil, err - } - if matchingIP != nil { - klog.V(4).Infof("Found valid IPv%d address %v for interface %q.", int(forFamily), matchingIP, intf.Name) - return matchingIP, nil - } - } - } - return nil, nil -} - -// memberOf tells if the IP is of the desired family. Used for checking interface addresses. -func memberOf(ip net.IP, family AddressFamily) bool { - if ip.To4() != nil { - return family == familyIPv4 - } else { - return family == familyIPv6 - } -} - -// chooseIPFromHostInterfaces looks at all system interfaces, trying to find one that is up that -// has a global unicast address (non-loopback, non-link local, non-point2point), and returns the IP. -// addressFamilies determines whether it prefers IPv4 or IPv6 -func chooseIPFromHostInterfaces(nw networkInterfacer, addressFamilies AddressFamilyPreference) (net.IP, error) { - intfs, err := nw.Interfaces() - if err != nil { - return nil, err - } - if len(intfs) == 0 { - return nil, fmt.Errorf("no interfaces found on host.") - } - for _, family := range addressFamilies { - klog.V(4).Infof("Looking for system interface with a global IPv%d address", uint(family)) - for _, intf := range intfs { - if !isInterfaceUp(&intf) { - klog.V(4).Infof("Skipping: down interface %q", intf.Name) - continue - } - if isLoopbackOrPointToPoint(&intf) { - klog.V(4).Infof("Skipping: LB or P2P interface %q", intf.Name) - continue - } - addrs, err := nw.Addrs(&intf) - if err != nil { - return nil, err - } - if len(addrs) == 0 { - klog.V(4).Infof("Skipping: no addresses on interface %q", intf.Name) - continue - } - for _, addr := range addrs { - ip, _, err := net.ParseCIDR(addr.String()) - if err != nil { - return nil, fmt.Errorf("Unable to parse CIDR for interface %q: %s", intf.Name, err) - } - if !memberOf(ip, family) { - klog.V(4).Infof("Skipping: no address family match for %q on interface %q.", ip, intf.Name) - continue - } - // TODO: Decide if should open up to allow IPv6 LLAs in future. - if !ip.IsGlobalUnicast() { - klog.V(4).Infof("Skipping: non-global address %q on interface %q.", ip, intf.Name) - continue - } - klog.V(4).Infof("Found global unicast address %q on interface %q.", ip, intf.Name) - return ip, nil - } - } - } - return nil, fmt.Errorf("no acceptable interface with global unicast address found on host") -} - -// ChooseHostInterface is a method used fetch an IP for a daemon. -// If there is no routing info file, it will choose a global IP from the system -// interfaces. Otherwise, it will use IPv4 and IPv6 route information to return the -// IP of the interface with a gateway on it (with priority given to IPv4). For a node -// with no internet connection, it returns error. -func ChooseHostInterface() (net.IP, error) { - return chooseHostInterface(preferIPv4) -} - -func chooseHostInterface(addressFamilies AddressFamilyPreference) (net.IP, error) { - var nw networkInterfacer = networkInterface{} - if _, err := os.Stat(ipv4RouteFile); os.IsNotExist(err) { - return chooseIPFromHostInterfaces(nw, addressFamilies) - } - routes, err := getAllDefaultRoutes() - if err != nil { - return nil, err - } - return chooseHostInterfaceFromRoute(routes, nw, addressFamilies) -} - -// networkInterfacer defines an interface for several net library functions. Production -// code will forward to net library functions, and unit tests will override the methods -// for testing purposes. -type networkInterfacer interface { - InterfaceByName(intfName string) (*net.Interface, error) - Addrs(intf *net.Interface) ([]net.Addr, error) - Interfaces() ([]net.Interface, error) -} - -// networkInterface implements the networkInterfacer interface for production code, just -// wrapping the underlying net library function calls. -type networkInterface struct{} - -func (_ networkInterface) InterfaceByName(intfName string) (*net.Interface, error) { - return net.InterfaceByName(intfName) -} - -func (_ networkInterface) Addrs(intf *net.Interface) ([]net.Addr, error) { - return intf.Addrs() -} - -func (_ networkInterface) Interfaces() ([]net.Interface, error) { - return net.Interfaces() -} - -// getAllDefaultRoutes obtains IPv4 and IPv6 default routes on the node. If unable -// to read the IPv4 routing info file, we return an error. If unable to read the IPv6 -// routing info file (which is optional), we'll just use the IPv4 route information. -// Using all the routing info, if no default routes are found, an error is returned. -func getAllDefaultRoutes() ([]Route, error) { - routes, err := v4File.extract() - if err != nil { - return nil, err - } - v6Routes, _ := v6File.extract() - routes = append(routes, v6Routes...) - if len(routes) == 0 { - return nil, noRoutesError{ - message: fmt.Sprintf("no default routes found in %q or %q", v4File.name, v6File.name), - } - } - return routes, nil -} - -// chooseHostInterfaceFromRoute cycles through each default route provided, looking for a -// global IP address from the interface for the route. If there are routes but no global -// address is obtained from the interfaces, it checks if the loopback interface has a global address. -// addressFamilies determines whether it prefers IPv4 or IPv6 -func chooseHostInterfaceFromRoute(routes []Route, nw networkInterfacer, addressFamilies AddressFamilyPreference) (net.IP, error) { - for _, family := range addressFamilies { - klog.V(4).Infof("Looking for default routes with IPv%d addresses", uint(family)) - for _, route := range routes { - if route.Family != family { - continue - } - klog.V(4).Infof("Default route transits interface %q", route.Interface) - finalIP, err := getIPFromInterface(route.Interface, family, nw) - if err != nil { - return nil, err - } - if finalIP != nil { - klog.V(4).Infof("Found active IP %v ", finalIP) - return finalIP, nil - } - // In case of network setups where default routes are present, but network - // interfaces use only link-local addresses (e.g. as described in RFC5549). - // the global IP is assigned to the loopback interface, and we should use it - loopbackIP, err := getIPFromLoopbackInterface(family, nw) - if err != nil { - return nil, err - } - if loopbackIP != nil { - klog.V(4).Infof("Found active IP %v on Loopback interface", loopbackIP) - return loopbackIP, nil - } - } - } - klog.V(4).Infof("No active IP found by looking at default routes") - return nil, fmt.Errorf("unable to select an IP from default routes.") -} - -// ResolveBindAddress returns the IP address of a daemon, based on the given bindAddress: -// If bindAddress is unset, it returns the host's default IP, as with ChooseHostInterface(). -// If bindAddress is unspecified or loopback, it returns the default IP of the same -// address family as bindAddress. -// Otherwise, it just returns bindAddress. -func ResolveBindAddress(bindAddress net.IP) (net.IP, error) { - addressFamilies := preferIPv4 - if bindAddress != nil && memberOf(bindAddress, familyIPv6) { - addressFamilies = preferIPv6 - } - - if bindAddress == nil || bindAddress.IsUnspecified() || bindAddress.IsLoopback() { - hostIP, err := chooseHostInterface(addressFamilies) - if err != nil { - return nil, err - } - bindAddress = hostIP - } - return bindAddress, nil -} - -// ChooseBindAddressForInterface choose a global IP for a specific interface, with priority given to IPv4. -// This is required in case of network setups where default routes are present, but network -// interfaces use only link-local addresses (e.g. as described in RFC5549). -// e.g when using BGP to announce a host IP over link-local ip addresses and this ip address is attached to the lo interface. -func ChooseBindAddressForInterface(intfName string) (net.IP, error) { - var nw networkInterfacer = networkInterface{} - for _, family := range preferIPv4 { - ip, err := getIPFromInterface(intfName, family, nw) - if err != nil { - return nil, err - } - if ip != nil { - return ip, nil - } - } - return nil, fmt.Errorf("unable to select an IP from %s network interface", intfName) -} |