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// Copyright 2015 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 ip
import (
"math/big"
"net"
)
// NextIP returns IP incremented by 1
func NextIP(ip net.IP) net.IP {
i := ipToInt(ip)
return intToIP(i.Add(i, big.NewInt(1)))
}
// PrevIP returns IP decremented by 1
func PrevIP(ip net.IP) net.IP {
i := ipToInt(ip)
return intToIP(i.Sub(i, big.NewInt(1)))
}
func ipToInt(ip net.IP) *big.Int {
if v := ip.To4(); v != nil {
return big.NewInt(0).SetBytes(v)
}
return big.NewInt(0).SetBytes(ip.To16())
}
func intToIP(i *big.Int) net.IP {
return net.IP(i.Bytes())
}
// Network masks off the host portion of the IP
func Network(ipn *net.IPNet) *net.IPNet {
return &net.IPNet{
IP: ipn.IP.Mask(ipn.Mask),
Mask: ipn.Mask,
}
}
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