Move around and fscrypt refactor

1 files changed, 180 insertions, 8 deletions

diff --git a/cmd/fscrypt/fscrypt.go b/cmd/fscrypt/fscrypt.go
index f1649fc..65da7cb 100644
--- a/cmd/fscrypt/fscrypt.go
+++ b/cmd/fscrypt/fscrypt.go
@@ -27,9 +27,35 @@ package main
 import (
 	"fmt"
 
+	"github.com/google/fscrypt/filesystem"
+	"github.com/google/fscrypt/security"
+	"github.com/pkg/errors"
+
+	"github.com/google/fscrypt/actions"
+
 	"github.com/google/fscrypt/cmd"
 )
 
+// Arguments used in fscrypt commands.
+var (
+	unusedMountpointArg = &cmd.Argument{
+		Name:  "mountpoint",
+		Usage: "path to a mountpoint on which to setup fscrypt",
+	}
+	usedMountpointArg = &cmd.Argument{
+		Name:  "mountpoint",
+		Usage: "path to a mountpoint being used with fscrypt",
+	}
+	directoryToEncryptArg = &cmd.Argument{
+		Name:  "directory",
+		Usage: "path to an empty directory to encrypt with fscrypt",
+	}
+	encryptedPathArg = &cmd.Argument{
+		Name:  "path",
+		Usage: "file or directory encrypted with fscrypt",
+	}
+)
+
 func main() { fscryptCommand.Run() }
 
 var fscryptCommand = cmd.Command{
@@ -40,10 +66,10 @@ var fscryptCommand = cmd.Command{
 		cmd.VersionUsage,
 	},
 	SubCommands: []*Command{
-		&setupCommand,
-		&encryptCommand,
-		// unlockCommand,
-		// purgeCommand,
+		setupCommand,
+		encryptCommand,
+		unlockCommand,
+		purgeCommand,
 		// statusCommand,
 		// metadataCommand,
 		cmd.VersionCommand,
@@ -58,9 +84,9 @@ var setupCommand = &cmd.Command{
 	Title: "setup a system/filesystem to use fscrypt",
 	UsageLines: []string{
 		fmt.Sprintf("[options]"),
-		fmt.Sprintf("%s [%s]", mountpointArg, cmd.ForceFlag),
+		fmt.Sprintf("%s [%s]", unusedMountpointArg, cmd.ForceFlag),
 	},
-	Arguments:    []*cmd.Argument{mountpointArg},
+	Arguments:    []*cmd.Argument{unusedMountpointArg},
 	InheritFlags: true,
 	Flags:        []cmd.Flag{configFileFlag, targetFlag, legacyFlag, cmd.ForceFlag},
 	ManPage:      &cmd.ManPage{Name: "fscrypt-setup", Section: 8},
@@ -80,5 +106,151 @@ func setupAction(c *cmd.Context) error {
 	}
 }
 
-// encrypt performs the functions of setupDirectory and Unlock in one command.
-var encryptCommand = &cmd.Command{}
+// encrypt takes an empty directory, enables encryption, and unlocks it.
+var encryptCommand = &cmd.Command{
+	Name:         "encrypt",
+	Title:        "start encrypting an empty directory",
+	UsageLines:   nil, // TODO(joerichey)
+	Arguments:    []*cmd.Argument{directoryToEncryptArg},
+	InheritFlags: true,
+	Flags: []cmd.Flag{sourceFlag, nameFlag, protectorFlag, policyFlag,
+		keyFileFlag, userFlag, skipUnlockFlag},
+	ManPage: &cmd.ManPage{Name: "fscrypt-encrypt", Section: 8},
+	Action:  encryptAction,
+}
+
+func encryptAction(c *cmd.Context) error {
+	if err := cmd.CheckExpectedArgs(c, 1, false); err != nil {
+		return err
+	}
+
+	path := c.Args[0]
+	if err := encryptPath(path); err != nil {
+		return err
+	}
+
+	if !skipUnlockFlag.Value {
+		fmt.Fprintf(cmd.Output, "%q is now encrypted, unlocked, and ready for use.\n", path)
+		return nil
+	}
+
+	fmt.Fprintf(cmd.Output, "%q is now encrypted, but it is still locked.\n", path)
+	fmt.Fprintf(cmd.Output, "It can be unlocked with: fscrypt unlock %q\n", path)
+	return nil
+}
+
+// unlock takes an encrypted path and makes it available for reading/writing.
+var unlockCommand = &cmd.Command{
+	Name:         "unlock",
+	Title:        "unlock an encrypted file or directory",
+	UsageLines:   nil, // TODO(joerichey)
+	Arguments:    []*cmd.Argument{encryptedPathArg},
+	InheritFlags: true,
+	Flags:        []cmd.Flag{protectorFlag, policyFlag, keyFileFlag, userFlag},
+	ManPage:      &cmd.ManPage{Name: "fscrypt-unlock", Section: 8},
+	Action:       unlockAction,
+}
+
+func unlockAction(c *cmd.Context) error {
+	if err := cmd.CheckExpectedArgs(c, 1, false); err != nil {
+		return err
+	}
+
+	path := c.Args[0]
+	if err := unlockPath(path); err != nil {
+		return err
+	}
+
+	fmt.Fprintf(cmd.Output, "%q is now unlocked and ready for use.\n", path)
+	return nil
+}
+
+// purge removes all the policy keys from the keyring (my require unmount).
+var purgeCommand = &cmd.Command{
+	Name:  "purge",
+	Title: "remove a directory's encryption keys",
+	UsageLines: []string{fmt.Sprintf("%s, [%s=false] [%s] [%s]",
+		usedMountpointArg, dropCachesFlag, userFlag, cmd.ForceFlag)},
+	Arguments:    []*cmd.Argument{usedMountpointArg},
+	InheritFlags: true,
+	Flags:        []cmd.Flag{dropCachesFlag, userFlag, cmd.ForceFlag},
+	ManPage:      &cmd.ManPage{Name: "fscrypt-purge", Section: 8},
+	Action:       purgeAction,
+}
+
+func purgeAction(c *cmd.Context) error {
+	if err := cmd.CheckExpectedArgs(c, 1, false); err != nil {
+		return err
+	}
+	if dropCachesFlag.Value {
+		if cmd.CheckIfRoot() != nil {
+			return ErrDropCachesPerm
+		}
+	}
+
+	targetUser, err := parseUserFlag(true)
+	if err != nil {
+		return err
+	}
+	ctx, err := actions.NewContextFromMountpoint(c.Args[0], target)
+	if err != nil {
+		return err
+	}
+
+	question := fmt.Sprintf("Purge all policy keys from %q", ctx.Mount.Path)
+	if dropCachesFlag.Value {
+		question += " and drop global inode cache"
+	}
+	warning := "Encrypted data on this filesystem will be inaccessible until unlocked again!!"
+	if err = cmd.AskConfirmation(question+"?", warning, false); err != nil {
+		return err
+	}
+	if err = actions.PurgeAllPolicies(ctx); err != nil {
+		return err
+	}
+	fmt.Fprintf(cmd.Output, "Policies purged from filesystem %q.\n", ctx.Mount.Path)
+
+	if !dropCachesFlag.Value {
+		fmt.Fprintf(cmd.Output, "Filesystem %q should now be unmounted.\n", cmd.Mount.Path)
+		return nil
+	}
+	if err = security.DropFilesystemCache(); err != nil {
+		return err
+	}
+	fmt.Fprintln(cmd.Output, "Encrypted data removed from filesystem cache.")
+	return nil
+}
+
+// status is a command that gets info about the system, a mountpoint, or a path.
+var statusCommand = &cmd.Command{
+	Name:       "status",
+	Title:      "get the status of the system or a path",
+	UsageLines: []string{"", usedMountpointArg.String(), encryptedPathArg.String()},
+	Flags:      []cmd.Flag{cmd.VerboseFlag, cmd.HelpFlag},
+	ManPage:    &cmd.ManPage{Name: "fscrypt-status", Section: 8},
+	Action:     statusAction,
+}
+
+func statusAction(c *cmd.Context) error {
+	switch len(c.Args) {
+	case 0:
+		// Case (1) - global status
+		return writeGlobalStatus()
+	case 1:
+		path := c.Args[0]
+		ctx, mntErr := actions.NewContextFromMountpoint(path, nil)
+
+		switch errors.Cause(mntErr) {
+		case nil:
+			// Case (2) - mountpoint status
+			return writeFilesystemStatus(ctx)
+		case filesystem.ErrNotAMountpoint:
+			// Case (3) - file or directory status
+			return writePathStatus(path)
+		default:
+			return mntErr
+		}
+	default:
+		return expectedArgsErr(c, 1, true)
+	}
+}