1 files changed, 137 insertions, 24 deletions
diff --git a/vendor/github.com/opencontainers/runc/libcontainer/configs/device.go b/vendor/github.com/opencontainers/runc/libcontainer/configs/device.go
index 8701bb212..632bf6ac4 100644
--- a/vendor/github.com/opencontainers/runc/libcontainer/configs/device.go
+++ b/vendor/github.com/opencontainers/runc/libcontainer/configs/device.go
@@ -3,30 +3,19 @@ package configs
 import (
 	"fmt"
 	"os"
+	"strconv"
 )
 
 const (
 	Wildcard = -1
 )
 
-// TODO Windows: This can be factored out in the future
-
 type Device struct {
-	// Device type, block, char, etc.
-	Type rune `json:"type"`
+	DeviceRule
 
 	// Path to the device.
 	Path string `json:"path"`
 
-	// Major is the device's major number.
-	Major int64 `json:"major"`
-
-	// Minor is the device's minor number.
-	Minor int64 `json:"minor"`
-
-	// Cgroup permissions format, rwm.
-	Permissions string `json:"permissions"`
-
 	// FileMode permission bits for the device.
 	FileMode os.FileMode `json:"file_mode"`
 
@@ -35,23 +24,147 @@ type Device struct {
 
 	// Gid of the device.
 	Gid uint32 `json:"gid"`
+}
 
-	// Write the file to the allowed list
-	Allow bool `json:"allow"`
+// DevicePermissions is a cgroupv1-style string to represent device access. It
+// has to be a string for backward compatibility reasons, hence why it has
+// methods to do set operations.
+type DevicePermissions string
+
+const (
+	deviceRead uint = (1 << iota)
+	deviceWrite
+	deviceMknod
+)
+
+func (p DevicePermissions) toSet() uint {
+	var set uint
+	for _, perm := range p {
+		switch perm {
+		case 'r':
+			set |= deviceRead
+		case 'w':
+			set |= deviceWrite
+		case 'm':
+			set |= deviceMknod
+		}
+	}
+	return set
+}
+
+func fromSet(set uint) DevicePermissions {
+	var perm string
+	if set&deviceRead == deviceRead {
+		perm += "r"
+	}
+	if set&deviceWrite == deviceWrite {
+		perm += "w"
+	}
+	if set&deviceMknod == deviceMknod {
+		perm += "m"
+	}
+	return DevicePermissions(perm)
+}
+
+// Union returns the union of the two sets of DevicePermissions.
+func (p DevicePermissions) Union(o DevicePermissions) DevicePermissions {
+	lhs := p.toSet()
+	rhs := o.toSet()
+	return fromSet(lhs | rhs)
+}
+
+// Difference returns the set difference of the two sets of DevicePermissions.
+// In set notation, A.Difference(B) gives you A\B.
+func (p DevicePermissions) Difference(o DevicePermissions) DevicePermissions {
+	lhs := p.toSet()
+	rhs := o.toSet()
+	return fromSet(lhs &^ rhs)
+}
+
+// Intersection computes the intersection of the two sets of DevicePermissions.
+func (p DevicePermissions) Intersection(o DevicePermissions) DevicePermissions {
+	lhs := p.toSet()
+	rhs := o.toSet()
+	return fromSet(lhs & rhs)
 }
 
-func (d *Device) CgroupString() string {
-	return fmt.Sprintf("%c %s:%s %s", d.Type, deviceNumberString(d.Major), deviceNumberString(d.Minor), d.Permissions)
+// IsEmpty returns whether the set of permissions in a DevicePermissions is
+// empty.
+func (p DevicePermissions) IsEmpty() bool {
+	return p == DevicePermissions("")
 }
 
-func (d *Device) Mkdev() int {
-	return int((d.Major << 8) | (d.Minor & 0xff) | ((d.Minor & 0xfff00) << 12))
+// IsValid returns whether the set of permissions is a subset of valid
+// permissions (namely, {r,w,m}).
+func (p DevicePermissions) IsValid() bool {
+	return p == fromSet(p.toSet())
 }
 
-// deviceNumberString converts the device number to a string return result.
-func deviceNumberString(number int64) string {
-	if number == Wildcard {
-		return "*"
+type DeviceType rune
+
+const (
+	WildcardDevice DeviceType = 'a'
+	BlockDevice    DeviceType = 'b'
+	CharDevice     DeviceType = 'c' // or 'u'
+	FifoDevice     DeviceType = 'p'
+)
+
+func (t DeviceType) IsValid() bool {
+	switch t {
+	case WildcardDevice, BlockDevice, CharDevice, FifoDevice:
+		return true
+	default:
+		return false
+	}
+}
+
+func (t DeviceType) CanMknod() bool {
+	switch t {
+	case BlockDevice, CharDevice, FifoDevice:
+		return true
+	default:
+		return false
+	}
+}
+
+func (t DeviceType) CanCgroup() bool {
+	switch t {
+	case WildcardDevice, BlockDevice, CharDevice:
+		return true
+	default:
+		return false
+	}
+}
+
+type DeviceRule struct {
+	// Type of device ('c' for char, 'b' for block). If set to 'a', this rule
+	// acts as a wildcard and all fields other than Allow are ignored.
+	Type DeviceType `json:"type"`
+
+	// Major is the device's major number.
+	Major int64 `json:"major"`
+
+	// Minor is the device's minor number.
+	Minor int64 `json:"minor"`
+
+	// Permissions is the set of permissions that this rule applies to (in the
+	// cgroupv1 format -- any combination of "rwm").
+	Permissions DevicePermissions `json:"permissions"`
+
+	// Allow specifies whether this rule is allowed.
+	Allow bool `json:"allow"`
+}
+
+func (d *DeviceRule) CgroupString() string {
+	var (
+		major = strconv.FormatInt(d.Major, 10)
+		minor = strconv.FormatInt(d.Minor, 10)
+	)
+	if d.Major == Wildcard {
+		major = "*"
+	}
+	if d.Minor == Wildcard {
+		minor = "*"
 	}
-	return fmt.Sprint(number)
+	return fmt.Sprintf("%c %s:%s %s", d.Type, major, minor, d.Permissions)
 }