k3s/pkg/netutil/iface.go
Brian Downs ba70c41cce
Initial Logging Output Update (#2246)
This attempts to update logging statements to make them consistent
through out the code base. It also adds additional context to messages
where possible, simplifies messages, and updates level where necessary.
2020-09-21 09:56:03 -07:00

58 lines
1.3 KiB
Go

package netutil
import (
"fmt"
"net"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
func GetIPFromInterface(ifaceName string) string {
ip, err := getIPFromInterface(ifaceName)
if err != nil {
logrus.Warn(errors.Wrap(err, "unable to get global unicast ip from interface name"))
} else {
logrus.Infof("Found ip %s from iface %s", ip, ifaceName)
}
return ip
}
func getIPFromInterface(ifaceName string) (string, error) {
iface, err := net.InterfaceByName(ifaceName)
if err != nil {
return "", err
}
addrs, err := iface.Addrs()
if err != nil {
return "", err
}
if iface.Flags&net.FlagUp == 0 {
return "", fmt.Errorf("the interface %s is not up", ifaceName)
}
globalUnicasts := []string{}
for _, addr := range addrs {
ip, _, err := net.ParseCIDR(addr.String())
if err != nil {
return "", errors.Wrapf(err, "unable to parse CIDR for interface %s", iface.Name)
}
// skipping if not ipv4
if ip.To4() == nil {
continue
}
if ip.IsGlobalUnicast() {
globalUnicasts = append(globalUnicasts, ip.String())
}
}
if len(globalUnicasts) > 1 {
return "", fmt.Errorf("multiple global unicast addresses defined for %s, please set ip from one of %v", ifaceName, globalUnicasts)
}
if len(globalUnicasts) == 1 {
return globalUnicasts[0], nil
}
return "", fmt.Errorf("can't find ip for interface %s", ifaceName)
}