diff --git a/opts/opts.go b/opts/opts.go
new file mode 100644
index 0000000..a1b8752
--- /dev/null
+++ b/opts/opts.go
@@ -0,0 +1,148 @@
+package opts
+
+import (
+	"fmt"
+	"github.com/dotcloud/docker/utils"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+// ListOpts type
+type ListOpts struct {
+	values    []string
+	validator ValidatorFctType
+}
+
+func NewListOpts(validator ValidatorFctType) ListOpts {
+	return ListOpts{
+		validator: validator,
+	}
+}
+
+func (opts *ListOpts) String() string {
+	return fmt.Sprintf("%v", []string(opts.values))
+}
+
+// Set validates if needed the input value and add it to the
+// internal slice.
+func (opts *ListOpts) Set(value string) error {
+	if opts.validator != nil {
+		v, err := opts.validator(value)
+		if err != nil {
+			return err
+		}
+		value = v
+	}
+	opts.values = append(opts.values, value)
+	return nil
+}
+
+// Delete remove the given element from the slice.
+func (opts *ListOpts) Delete(key string) {
+	for i, k := range opts.values {
+		if k == key {
+			opts.values = append(opts.values[:i], opts.values[i+1:]...)
+			return
+		}
+	}
+}
+
+// GetMap returns the content of values in a map in order to avoid
+// duplicates.
+// FIXME: can we remove this?
+func (opts *ListOpts) GetMap() map[string]struct{} {
+	ret := make(map[string]struct{})
+	for _, k := range opts.values {
+		ret[k] = struct{}{}
+	}
+	return ret
+}
+
+// GetAll returns the values' slice.
+// FIXME: Can we remove this?
+func (opts *ListOpts) GetAll() []string {
+	return opts.values
+}
+
+// Get checks the existence of the given key.
+func (opts *ListOpts) Get(key string) bool {
+	for _, k := range opts.values {
+		if k == key {
+			return true
+		}
+	}
+	return false
+}
+
+// Len returns the amount of element in the slice.
+func (opts *ListOpts) Len() int {
+	return len(opts.values)
+}
+
+// Validators
+type ValidatorFctType func(val string) (string, error)
+
+func ValidateAttach(val string) (string, error) {
+	if val != "stdin" && val != "stdout" && val != "stderr" {
+		return val, fmt.Errorf("Unsupported stream name: %s", val)
+	}
+	return val, nil
+}
+
+func ValidateLink(val string) (string, error) {
+	if _, err := parseLink(val); err != nil {
+		return val, err
+	}
+	return val, nil
+}
+
+// FIXME: this is a duplicate of docker.utils.parseLink.
+// 	it can't be moved to a separate links/ package because
+//	links depends on Container which is defined in the core.
+//
+// Links come in the format of
+// name:alias
+func parseLink(rawLink string) (map[string]string, error) {
+	return utils.PartParser("name:alias", rawLink)
+}
+
+func ValidatePath(val string) (string, error) {
+	var containerPath string
+
+	if strings.Count(val, ":") > 2 {
+		return val, fmt.Errorf("bad format for volumes: %s", val)
+	}
+
+	splited := strings.SplitN(val, ":", 2)
+	if len(splited) == 1 {
+		containerPath = splited[0]
+		val = filepath.Clean(splited[0])
+	} else {
+		containerPath = splited[1]
+		val = fmt.Sprintf("%s:%s", splited[0], filepath.Clean(splited[1]))
+	}
+
+	if !filepath.IsAbs(containerPath) {
+		return val, fmt.Errorf("%s is not an absolute path", containerPath)
+	}
+	return val, nil
+}
+
+func ValidateEnv(val string) (string, error) {
+	arr := strings.Split(val, "=")
+	if len(arr) > 1 {
+		return val, nil
+	}
+	return fmt.Sprintf("%s=%s", val, os.Getenv(val)), nil
+}
+
+func ValidateIp4Address(val string) (string, error) {
+	re := regexp.MustCompile(`^(([0-9]+\.){3}([0-9]+))\s*$`)
+	var ns = re.FindSubmatch([]byte(val))
+	if len(ns) > 0 {
+		return string(ns[1]), nil
+	}
+	return "", fmt.Errorf("%s is not an ip4 address", val)
+}
diff --git a/opts/opts_test.go b/opts/opts_test.go
new file mode 100644
index 0000000..a5c1fac
--- /dev/null
+++ b/opts/opts_test.go
@@ -0,0 +1,24 @@
+package opts
+
+import (
+	"testing"
+)
+
+func TestValidateIP4(t *testing.T) {
+	if ret, err := ValidateIp4Address(`1.2.3.4`); err != nil || ret == "" {
+		t.Fatalf("ValidateIp4Address(`1.2.3.4`) got %s %s", ret, err)
+	}
+
+	if ret, err := ValidateIp4Address(`127.0.0.1`); err != nil || ret == "" {
+		t.Fatalf("ValidateIp4Address(`127.0.0.1`) got %s %s", ret, err)
+	}
+
+	if ret, err := ValidateIp4Address(`127`); err == nil || ret != "" {
+		t.Fatalf("ValidateIp4Address(`127`) got %s %s", ret, err)
+	}
+
+	if ret, err := ValidateIp4Address(`random invalid string`); err == nil || ret != "" {
+		t.Fatalf("ValidateIp4Address(`random invalid string`) got %s %s", ret, err)
+	}
+
+}