1 files changed, 38 insertions, 0 deletions

diff --git a/vendor/github.com/apparentlymart/go-cidr/cidr/wrangling.go b/vendor/github.com/apparentlymart/go-cidr/cidr/wrangling.go
new file mode 100644
index 0000000..861a5f6
--- /dev/null
+++ b/vendor/github.com/apparentlymart/go-cidr/cidr/wrangling.go
@@ -0,0 +1,38 @@
+package cidr
+
+import (
+        "fmt"
+        "math/big"
+        "net"
+)
+
+func ipToInt(ip net.IP) (*big.Int, int) {
+        val := &big.Int{}
+        val.SetBytes([]byte(ip))
+        if len(ip) == net.IPv4len {
+                return val, 32
+        } else if len(ip) == net.IPv6len {
+                return val, 128
+        } else {
+                panic(fmt.Errorf("Unsupported address length %d", len(ip)))
+        }
+}
+
+func intToIP(ipInt *big.Int, bits int) net.IP {
+        ipBytes := ipInt.Bytes()
+        ret := make([]byte, bits/8)
+        // Pack our IP bytes into the end of the return array,
+        // since big.Int.Bytes() removes front zero padding.
+        for i := 1; i <= len(ipBytes); i++ {
+                ret[len(ret)-i] = ipBytes[len(ipBytes)-i]
+        }
+        return net.IP(ret)
+}
+
+func insertNumIntoIP(ip net.IP, num int, prefixLen int) net.IP {
+        ipInt, totalBits := ipToInt(ip)
+        bigNum := big.NewInt(int64(num))
+        bigNum.Lsh(bigNum, uint(totalBits-prefixLen))
+        ipInt.Or(ipInt, bigNum)
+        return intToIP(ipInt, totalBits)
+}