diff --git a/vendor/github.com/spf13/pflag/ip.go b/vendor/github.com/spf13/pflag/ip.go
new file mode 100644
index 0000000..3d414ba
--- /dev/null
+++ b/vendor/github.com/spf13/pflag/ip.go
@@ -0,0 +1,94 @@
+package pflag
+
+import (
+	"fmt"
+	"net"
+	"strings"
+)
+
+// -- net.IP value
+type ipValue net.IP
+
+func newIPValue(val net.IP, p *net.IP) *ipValue {
+	*p = val
+	return (*ipValue)(p)
+}
+
+func (i *ipValue) String() string { return net.IP(*i).String() }
+func (i *ipValue) Set(s string) error {
+	ip := net.ParseIP(strings.TrimSpace(s))
+	if ip == nil {
+		return fmt.Errorf("failed to parse IP: %q", s)
+	}
+	*i = ipValue(ip)
+	return nil
+}
+
+func (i *ipValue) Type() string {
+	return "ip"
+}
+
+func ipConv(sval string) (interface{}, error) {
+	ip := net.ParseIP(sval)
+	if ip != nil {
+		return ip, nil
+	}
+	return nil, fmt.Errorf("invalid string being converted to IP address: %s", sval)
+}
+
+// GetIP return the net.IP value of a flag with the given name
+func (f *FlagSet) GetIP(name string) (net.IP, error) {
+	val, err := f.getFlagType(name, "ip", ipConv)
+	if err != nil {
+		return nil, err
+	}
+	return val.(net.IP), nil
+}
+
+// IPVar defines an net.IP flag with specified name, default value, and usage string.
+// The argument p points to an net.IP variable in which to store the value of the flag.
+func (f *FlagSet) IPVar(p *net.IP, name string, value net.IP, usage string) {
+	f.VarP(newIPValue(value, p), name, "", usage)
+}
+
+// IPVarP is like IPVar, but accepts a shorthand letter that can be used after a single dash.
+func (f *FlagSet) IPVarP(p *net.IP, name, shorthand string, value net.IP, usage string) {
+	f.VarP(newIPValue(value, p), name, shorthand, usage)
+}
+
+// IPVar defines an net.IP flag with specified name, default value, and usage string.
+// The argument p points to an net.IP variable in which to store the value of the flag.
+func IPVar(p *net.IP, name string, value net.IP, usage string) {
+	CommandLine.VarP(newIPValue(value, p), name, "", usage)
+}
+
+// IPVarP is like IPVar, but accepts a shorthand letter that can be used after a single dash.
+func IPVarP(p *net.IP, name, shorthand string, value net.IP, usage string) {
+	CommandLine.VarP(newIPValue(value, p), name, shorthand, usage)
+}
+
+// IP defines an net.IP flag with specified name, default value, and usage string.
+// The return value is the address of an net.IP variable that stores the value of the flag.
+func (f *FlagSet) IP(name string, value net.IP, usage string) *net.IP {
+	p := new(net.IP)
+	f.IPVarP(p, name, "", value, usage)
+	return p
+}
+
+// IPP is like IP, but accepts a shorthand letter that can be used after a single dash.
+func (f *FlagSet) IPP(name, shorthand string, value net.IP, usage string) *net.IP {
+	p := new(net.IP)
+	f.IPVarP(p, name, shorthand, value, usage)
+	return p
+}
+
+// IP defines an net.IP flag with specified name, default value, and usage string.
+// The return value is the address of an net.IP variable that stores the value of the flag.
+func IP(name string, value net.IP, usage string) *net.IP {
+	return CommandLine.IPP(name, "", value, usage)
+}
+
+// IPP is like IP, but accepts a shorthand letter that can be used after a single dash.
+func IPP(name, shorthand string, value net.IP, usage string) *net.IP {
+	return CommandLine.IPP(name, shorthand, value, usage)
+}