68 lines
1.7 KiB
Go

// Copyright 2017 CNI 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 main
import (
"crypto/sha512"
"fmt"
"net"
"github.com/vishvananda/netlink"
)
const maxChainNameLength = 28
// fmtIpPort correctly formats ip:port literals for iptables and ip6tables -
// need to wrap v6 literals in a []
func fmtIpPort(ip net.IP, port int) string {
if ip.To4() == nil {
return fmt.Sprintf("[%s]:%d", ip.String(), port)
}
return fmt.Sprintf("%s:%d", ip.String(), port)
}
func localhostIP(isV6 bool) string {
if isV6 {
return "::1"
}
return "127.0.0.1"
}
// getRoutableHostIF will try and determine which interface routes the container's
// traffic. This is the one on which we disable martian filtering.
func getRoutableHostIF(containerIP net.IP) string {
routes, err := netlink.RouteGet(containerIP)
if err != nil {
return ""
}
for _, route := range routes {
link, err := netlink.LinkByIndex(route.LinkIndex)
if err != nil {
continue
}
return link.Attrs().Name
}
return ""
}
func formatChainName(prefix, name, id string) string {
chainBytes := sha512.Sum512([]byte(name + id))
chain := fmt.Sprintf("CNI-%s%x", prefix, chainBytes)
return chain[:maxChainNameLength]
}