netavark IPAM assignment

Add a new boltdb to handle IPAM assignment.

The db structure is the following:
Each network has their own bucket with the network name as bucket key.
Inside the network bucket there is an ID bucket which maps the container ID (key)
to a json array of ip addresses (value).
The network bucket also has a bucket for each subnet, the subnet is used as key.
Inside the subnet bucket an ip is used as key and the container ID as value.

The db should be stored on a tmpfs to ensure we always have a clean
state after a reboot.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

2 files changed, 64 insertions, 1 deletions

diff --git a/libpod/network/util/ip.go b/libpod/network/util/ip.go
index e75107a1c..e82b4a781 100644
--- a/libpod/network/util/ip.go
+++ b/libpod/network/util/ip.go
@@ -1,6 +1,8 @@
 package util
 
-import "net"
+import (
+	"net"
+)
 
 // IsIPv6 returns true if netIP is IPv6.
 func IsIPv6(netIP net.IP) bool {
@@ -44,3 +46,11 @@ func FirstIPInSubnet(addr *net.IPNet) (net.IP, error) { //nolint:interfacer
 	cidr.IP[len(cidr.IP)-1]++
 	return cidr.IP, nil
 }
+
+// NormalizeIP will transform the given ip to the 4 byte len ipv4 if possible
+func NormalizeIP(ip *net.IP) {
+	ipv4 := ip.To4()
+	if ipv4 != nil {
+		*ip = ipv4
+	}
+}
diff --git a/libpod/network/util/ip_calc.go b/libpod/network/util/ip_calc.go
new file mode 100644
index 000000000..a27ddf78b
--- /dev/null
+++ b/libpod/network/util/ip_calc.go
@@ -0,0 +1,53 @@
+// 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 util
+
+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)))
+}
+
+// Cmp compares two IPs, returning the usual ordering:
+// a < b : -1
+// a == b : 0
+// a > b : 1
+func Cmp(a, b net.IP) int {
+	aa := ipToInt(a)
+	bb := ipToInt(b)
+	return aa.Cmp(bb)
+}
+
+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())
+}