updates

Signed-off-by: Jess Frazelle <jess@mesosphere.com>

vendor/github.com/opencontainers/runc/libcontainer/configs/validate/validator.go

@@ -0,0 +1,133 @@
+package validate
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/opencontainers/runc/libcontainer/configs"
+)
+
+type Validator interface {
+	Validate(*configs.Config) error
+}
+
+func New() Validator {
+	return &ConfigValidator{}
+}
+
+type ConfigValidator struct {
+}
+
+func (v *ConfigValidator) Validate(config *configs.Config) error {
+	if err := v.rootfs(config); err != nil {
+		return err
+	}
+	if err := v.network(config); err != nil {
+		return err
+	}
+	if err := v.hostname(config); err != nil {
+		return err
+	}
+	if err := v.security(config); err != nil {
+		return err
+	}
+	if err := v.usernamespace(config); err != nil {
+		return err
+	}
+	if err := v.sysctl(config); err != nil {
+		return err
+	}
+	return nil
+}
+
+// rootfs validates if the rootfs is an absolute path and is not a symlink
+// to the container's root filesystem.
+func (v *ConfigValidator) rootfs(config *configs.Config) error {
+	cleaned, err := filepath.Abs(config.Rootfs)
+	if err != nil {
+		return err
+	}
+	if cleaned, err = filepath.EvalSymlinks(cleaned); err != nil {
+		return err
+	}
+	if filepath.Clean(config.Rootfs) != cleaned {
+		return fmt.Errorf("%s is not an absolute path or is a symlink", config.Rootfs)
+	}
+	return nil
+}
+
+func (v *ConfigValidator) network(config *configs.Config) error {
+	if !config.Namespaces.Contains(configs.NEWNET) {
+		if len(config.Networks) > 0 || len(config.Routes) > 0 {
+			return fmt.Errorf("unable to apply network settings without a private NET namespace")
+		}
+	}
+	return nil
+}
+
+func (v *ConfigValidator) hostname(config *configs.Config) error {
+	if config.Hostname != "" && !config.Namespaces.Contains(configs.NEWUTS) {
+		return fmt.Errorf("unable to set hostname without a private UTS namespace")
+	}
+	return nil
+}
+
+func (v *ConfigValidator) security(config *configs.Config) error {
+	// restrict sys without mount namespace
+	if (len(config.MaskPaths) > 0 || len(config.ReadonlyPaths) > 0) &&
+		!config.Namespaces.Contains(configs.NEWNS) {
+		return fmt.Errorf("unable to restrict sys entries without a private MNT namespace")
+	}
+	return nil
+}
+
+func (v *ConfigValidator) usernamespace(config *configs.Config) error {
+	if config.Namespaces.Contains(configs.NEWUSER) {
+		if _, err := os.Stat("/proc/self/ns/user"); os.IsNotExist(err) {
+			return fmt.Errorf("USER namespaces aren't enabled in the kernel")
+		}
+	} else {
+		if config.UidMappings != nil || config.GidMappings != nil {
+			return fmt.Errorf("User namespace mappings specified, but USER namespace isn't enabled in the config")
+		}
+	}
+	return nil
+}
+
+// sysctl validates that the specified sysctl keys are valid or not.
+// /proc/sys isn't completely namespaced and depending on which namespaces
+// are specified, a subset of sysctls are permitted.
+func (v *ConfigValidator) sysctl(config *configs.Config) error {
+	validSysctlMap := map[string]bool{
+		"kernel.msgmax":          true,
+		"kernel.msgmnb":          true,
+		"kernel.msgmni":          true,
+		"kernel.sem":             true,
+		"kernel.shmall":          true,
+		"kernel.shmmax":          true,
+		"kernel.shmmni":          true,
+		"kernel.shm_rmid_forced": true,
+	}
+
+	for s := range config.Sysctl {
+		if validSysctlMap[s] || strings.HasPrefix(s, "fs.mqueue.") {
+			if config.Namespaces.Contains(configs.NEWIPC) {
+				continue
+			} else {
+				return fmt.Errorf("sysctl %q is not allowed in the hosts ipc namespace", s)
+			}
+		}
+		if strings.HasPrefix(s, "net.") {
+			if config.Namespaces.Contains(configs.NEWNET) {
+				continue
+			} else {
+				return fmt.Errorf("sysctl %q is not allowed in the hosts network namespace", s)
+			}
+		}
+		return fmt.Errorf("sysctl %q is not in a separate kernel namespace", s)
+	}
+
+	return nil
+}