Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

fix bug on getting NextIP of addresses with first byte 0 #782

Merged
merged 1 commit into from
Jan 9, 2023
Merged

fix bug on getting NextIP of addresses with first byte 0 #782

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
76 changes: 60 additions & 16 deletions pkg/ip/cidr.go
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -19,43 +19,87 @@ import (
"net"
)

// NextIP returns IP incremented by 1
// NextIP returns IP incremented by 1, if IP is invalid, return nil
func NextIP(ip net.IP) net.IP {
i := ipToInt(ip)
return intToIP(i.Add(i, big.NewInt(1)))
normalizedIP := normalizeIP(ip)
if normalizedIP == nil {
return nil
}

i := ipToInt(normalizedIP)
return intToIP(i.Add(i, big.NewInt(1)), len(normalizedIP) == net.IPv6len)
}

// PrevIP returns IP decremented by 1
// PrevIP returns IP decremented by 1, if IP is invalid, return nil
func PrevIP(ip net.IP) net.IP {
i := ipToInt(ip)
return intToIP(i.Sub(i, big.NewInt(1)))
normalizedIP := normalizeIP(ip)
if normalizedIP == nil {
return nil
}

i := ipToInt(normalizedIP)
return intToIP(i.Sub(i, big.NewInt(1)), len(normalizedIP) == net.IPv6len)
}

// Cmp compares two IPs, returning the usual ordering:
// a < b : -1
// a == b : 0
// a > b : 1
// incomparable : -2
func Cmp(a, b net.IP) int {
aa := ipToInt(a)
bb := ipToInt(b)
return aa.Cmp(bb)
normalizedA := normalizeIP(a)
normalizedB := normalizeIP(b)

if len(normalizedA) == len(normalizedB) && len(normalizedA) != 0 {
return ipToInt(normalizedA).Cmp(ipToInt(normalizedB))
}

return -2
}

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)
}

func intToIP(i *big.Int, isIPv6 bool) net.IP {
intBytes := i.Bytes()

if len(intBytes) == net.IPv4len || len(intBytes) == net.IPv6len {
return intBytes
}

if isIPv6 {
return append(make([]byte, net.IPv6len-len(intBytes)), intBytes...)
}
return big.NewInt(0).SetBytes(ip.To16())

return append(make([]byte, net.IPv4len-len(intBytes)), intBytes...)
}

func intToIP(i *big.Int) net.IP {
return net.IP(i.Bytes())
// normalizeIP will normalize IP by family,
// IPv4 : 4-byte form
// IPv6 : 16-byte form
// others : nil
func normalizeIP(ip net.IP) net.IP {
if ipTo4 := ip.To4(); ipTo4 != nil {
return ipTo4
}
return ip.To16()
}

// Network masks off the host portion of the IP
// Network masks off the host portion of the IP, if IPNet is invalid,
// return nil
func Network(ipn *net.IPNet) *net.IPNet {
if ipn == nil {
return nil
}

maskedIP := ipn.IP.Mask(ipn.Mask)
if maskedIP == nil {
return nil
}

return &net.IPNet{
IP: ipn.IP.Mask(ipn.Mask),
IP: maskedIP,
Mask: ipn.Mask,
}
}
247 changes: 247 additions & 0 deletions pkg/ip/cidr_test.go
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,247 @@
// Copyright 2022 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 (
"net"

. "github.com/onsi/ginkgo"
. "github.com/onsi/gomega"
)

var _ = Describe("CIDR functions", func() {
It("NextIP", func() {
testCases := []struct {
ip net.IP
nextIP net.IP
}{
{
[]byte{192, 0, 2},
nil,
},
{
net.ParseIP("192.168.0.1"),
net.IPv4(192, 168, 0, 2).To4(),
},
{
net.ParseIP("192.168.0.255"),
net.IPv4(192, 168, 1, 0).To4(),
},
{
net.ParseIP("0.1.0.5"),
net.IPv4(0, 1, 0, 6).To4(),
},
{
net.ParseIP("AB12::123"),
net.ParseIP("AB12::124"),
},
{
net.ParseIP("AB12::FFFF"),
net.ParseIP("AB12::1:0"),
},
{
net.ParseIP("0::123"),
net.ParseIP("0::124"),
},
}

for _, test := range testCases {
ip := NextIP(test.ip)

Expect(ip).To(Equal(test.nextIP))
}
})

It("PrevIP", func() {
testCases := []struct {
ip net.IP
prevIP net.IP
}{
{
[]byte{192, 0, 2},
nil,
},
{
net.ParseIP("192.168.0.2"),
net.IPv4(192, 168, 0, 1).To4(),
},
{
net.ParseIP("192.168.1.0"),
net.IPv4(192, 168, 0, 255).To4(),
},
{
net.ParseIP("0.1.0.5"),
net.IPv4(0, 1, 0, 4).To4(),
},
{
net.ParseIP("AB12::123"),
net.ParseIP("AB12::122"),
},
{
net.ParseIP("AB12::1:0"),
net.ParseIP("AB12::FFFF"),
},
{
net.ParseIP("0::124"),
net.ParseIP("0::123"),
},
}

for _, test := range testCases {
ip := PrevIP(test.ip)

Expect(ip).To(Equal(test.prevIP))
}
})

It("Cmp", func() {
testCases := []struct {
a net.IP
b net.IP
result int
}{
{
net.ParseIP("192.168.0.2"),
nil,
-2,
},
{
net.ParseIP("192.168.0.2"),
[]byte{192, 168, 5},
-2,
},
{
net.ParseIP("192.168.0.2"),
net.ParseIP("AB12::123"),
-2,
},
{
net.ParseIP("192.168.0.2"),
net.ParseIP("192.168.0.5"),
-1,
},
{
net.ParseIP("192.168.0.2"),
net.ParseIP("192.168.0.5").To4(),
-1,
},
{
net.ParseIP("192.168.0.10"),
net.ParseIP("192.168.0.5"),
1,
},
{
net.ParseIP("192.168.0.10"),
net.ParseIP("192.168.0.10"),
0,
},
{
net.ParseIP("192.168.0.10"),
net.ParseIP("192.168.0.10").To4(),
0,
},
{
net.ParseIP("AB12::122"),
net.ParseIP("AB12::123"),
-1,
},
{
net.ParseIP("AB12::210"),
net.ParseIP("AB12::123"),
1,
},
{
net.ParseIP("AB12::210"),
net.ParseIP("AB12::210"),
0,
},
}

for _, test := range testCases {
result := Cmp(test.a, test.b)

Expect(result).To(Equal(test.result))
}
})

It("Network", func() {
testCases := []struct {
ipNet *net.IPNet
result *net.IPNet
}{
{
nil,
nil,
},
{
&net.IPNet{
IP: nil,
Mask: net.IPv4Mask(255, 255, 255, 0),
},
nil,
},
{
&net.IPNet{
IP: net.IPv4(192, 168, 0, 1),
Mask: nil,
},
nil,
},
{
&net.IPNet{
IP: net.ParseIP("AB12::123"),
Mask: net.IPv4Mask(255, 255, 255, 0),
},
nil,
},
{
&net.IPNet{
IP: net.IPv4(192, 168, 0, 100).To4(),
Mask: net.CIDRMask(120, 128),
},
&net.IPNet{
IP: net.IPv4(192, 168, 0, 0).To4(),
Mask: net.CIDRMask(120, 128),
},
},
{
&net.IPNet{
IP: net.IPv4(192, 168, 0, 100),
Mask: net.CIDRMask(24, 32),
},
&net.IPNet{
IP: net.IPv4(192, 168, 0, 0).To4(),
Mask: net.CIDRMask(24, 32),
},
},
{
&net.IPNet{
IP: net.ParseIP("AB12::123"),
Mask: net.CIDRMask(120, 128),
},
&net.IPNet{
IP: net.ParseIP("AB12::100"),
Mask: net.CIDRMask(120, 128),
},
},
}

for _, test := range testCases {
result := Network(test.ipNet)

Expect(result).To(Equal(test.result))
}
})
})