Add external-snapshotter to ceph-csi

Adding extenal-provisoner will help us to
test snapshot functionality

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

vendor/k8s.io/utils/net/net.go

@@ -16,7 +16,98 @@ limitations under the License.
 
 package net
 
-import "net"
+import (
+	"fmt"
+	"net"
+)
+
+// ParseCIDRs parses a list of cidrs and return error if any is invalid.
+// order is maintained
+func ParseCIDRs(cidrsString []string) ([]*net.IPNet, error) {
+	cidrs := make([]*net.IPNet, 0, len(cidrsString))
+	for _, cidrString := range cidrsString {
+		_, cidr, err := net.ParseCIDR(cidrString)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse cidr value:%q with error:%v", cidrString, err)
+		}
+		cidrs = append(cidrs, cidr)
+	}
+	return cidrs, nil
+}
+
+// IsDualStackIPs returns if a slice of ips is:
+// - all are valid ips
+// - at least one ip from each family (v4 or v6)
+func IsDualStackIPs(ips []net.IP) (bool, error) {
+	v4Found := false
+	v6Found := false
+	for _, ip := range ips {
+		if ip == nil {
+			return false, fmt.Errorf("ip %v is invalid", ip)
+		}
+
+		if v4Found && v6Found {
+			continue
+		}
+
+		if IsIPv6(ip) {
+			v6Found = true
+			continue
+		}
+
+		v4Found = true
+	}
+
+	return (v4Found && v6Found), nil
+}
+
+// IsDualStackIPStrings returns if
+// - all are valid ips
+// - at least one ip from each family (v4 or v6)
+func IsDualStackIPStrings(ips []string) (bool, error) {
+	parsedIPs := make([]net.IP, 0, len(ips))
+	for _, ip := range ips {
+		parsedIP := net.ParseIP(ip)
+		parsedIPs = append(parsedIPs, parsedIP)
+	}
+	return IsDualStackIPs(parsedIPs)
+}
+
+// IsDualStackCIDRs returns if
+// - all are valid cidrs
+// - at least one cidr from each family (v4 or v6)
+func IsDualStackCIDRs(cidrs []*net.IPNet) (bool, error) {
+	v4Found := false
+	v6Found := false
+	for _, cidr := range cidrs {
+		if cidr == nil {
+			return false, fmt.Errorf("cidr %v is invalid", cidr)
+		}
+
+		if v4Found && v6Found {
+			continue
+		}
+
+		if IsIPv6(cidr.IP) {
+			v6Found = true
+			continue
+		}
+		v4Found = true
+	}
+
+	return v4Found && v6Found, nil
+}
+
+// IsDualStackCIDRStrings returns if
+// - all are valid cidrs
+// - at least one cidr from each family (v4 or v6)
+func IsDualStackCIDRStrings(cidrs []string) (bool, error) {
+	parsedCIDRs, err := ParseCIDRs(cidrs)
+	if err != nil {
+		return false, err
+	}
+	return IsDualStackCIDRs(parsedCIDRs)
+}
 
 // IsIPv6 returns if netIP is IPv6.
 func IsIPv6(netIP net.IP) bool {
@@ -35,3 +126,9 @@ func IsIPv6CIDRString(cidr string) bool {
 	ip, _, _ := net.ParseCIDR(cidr)
 	return IsIPv6(ip)
 }
+
+// IsIPv6CIDR returns if a cidr is ipv6
+func IsIPv6CIDR(cidr *net.IPNet) bool {
+	ip := cidr.IP
+	return IsIPv6(ip)
+}