Merge pull request #2910 from mtdcr/repository-file

Add new option --repository-file (default: $RESTIC_REPOSITORY_FILE)

changelog/unreleased/pull-2910

@@ -0,0 +1,10 @@
+Enhancement: New option --repository-file
+
+We've added a new command-line option --repository-file as an alternative
+to -r. This allows to read the repository URL from a file in order to
+prevent certain types of information leaks, especially for URLs containing
+credentials.
+
+https://github.com/restic/restic/issues/1458
+https://github.com/restic/restic/issues/2900
+https://github.com/restic/restic/pull/2910

cmd/restic/cmd_init.go

@@ -52,7 +52,12 @@ func runInit(opts InitOptions, gopts GlobalOptions, args []string) error {
 		return err
 	}
 
-	be, err := create(gopts.Repo, gopts.extended)
+	repo, err := ReadRepo(gopts)
+	if err != nil {
+		return err
+	}
+
+	be, err := create(repo, gopts.extended)
 	if err != nil {
 		return errors.Fatalf("create repository at %s failed: %v\n", location.StripPassword(gopts.Repo), err)
 	}

cmd/restic/global.go

@@ -49,6 +49,7 @@ type backendWrapper func(r restic.Backend) (restic.Backend, error)
 // GlobalOptions hold all global options for restic.
 type GlobalOptions struct {
 	Repo            string
+	RepositoryFile  string
 	PasswordFile    string
 	PasswordCommand string
 	KeyHint         string
@@ -101,6 +102,7 @@ func init() {
 
 	f := cmdRoot.PersistentFlags()
 	f.StringVarP(&globalOptions.Repo, "repo", "r", os.Getenv("RESTIC_REPOSITORY"), "`repository` to backup to or restore from (default: $RESTIC_REPOSITORY)")
+	f.StringVarP(&globalOptions.RepositoryFile, "repository-file", "", os.Getenv("RESTIC_REPOSITORY_FILE"), "`file` to read the repository location from (default: $RESTIC_REPOSITORY_FILE)")
 	f.StringVarP(&globalOptions.PasswordFile, "password-file", "p", os.Getenv("RESTIC_PASSWORD_FILE"), "`file` to read the repository password from (default: $RESTIC_PASSWORD_FILE)")
 	f.StringVarP(&globalOptions.KeyHint, "key-hint", "", os.Getenv("RESTIC_KEY_HINT"), "`key` ID of key to try decrypting first (default: $RESTIC_KEY_HINT)")
 	f.StringVarP(&globalOptions.PasswordCommand, "password-command", "", os.Getenv("RESTIC_PASSWORD_COMMAND"), "shell `command` to obtain the repository password from (default: $RESTIC_PASSWORD_COMMAND)")
@@ -382,15 +384,41 @@ func ReadPasswordTwice(gopts GlobalOptions, prompt1, prompt2 string) (string, er
 	return pw1, nil
 }
 
+func ReadRepo(opts GlobalOptions) (string, error) {
+	if opts.Repo == "" && opts.RepositoryFile == "" {
+		return "", errors.Fatal("Please specify repository location (-r or --repository-file)")
+	}
+
+	repo := opts.Repo
+	if opts.RepositoryFile != "" {
+		if repo != "" {
+			return "", errors.Fatal("Options -r and --repository-file are mutually exclusive, please specify only one")
+		}
+
+		s, err := textfile.Read(opts.RepositoryFile)
+		if os.IsNotExist(errors.Cause(err)) {
+			return "", errors.Fatalf("%s does not exist", opts.RepositoryFile)
+		}
+		if err != nil {
+			return "", err
+		}
+
+		repo = strings.TrimSpace(string(s))
+	}
+
+	return repo, nil
+}
+
 const maxKeys = 20
 
 // OpenRepository reads the password and opens the repository.
 func OpenRepository(opts GlobalOptions) (*repository.Repository, error) {
-	if opts.Repo == "" {
-		return nil, errors.Fatal("Please specify repository location (-r)")
+	repo, err := ReadRepo(opts)
+	if err != nil {
+		return nil, err
 	}
 
-	be, err := open(opts.Repo, opts, opts.extended)
+	be, err := open(repo, opts, opts.extended)
 	if err != nil {
 		return nil, err
 	}

cmd/restic/global_test.go

@@ -2,8 +2,11 @@ package main
 
 import (
 	"bytes"
+	"io/ioutil"
+	"path/filepath"
 	"testing"
 
+	"github.com/restic/restic/internal/test"
 	rtest "github.com/restic/restic/internal/test"
 )
 
@@ -26,3 +29,33 @@ func Test_PrintFunctionsRespectsGlobalStdout(t *testing.T) {
 		buf.Reset()
 	}
 }
+
+func TestReadRepo(t *testing.T) {
+	tempDir, cleanup := test.TempDir(t)
+	defer cleanup()
+
+	// test --repo option
+	var opts GlobalOptions
+	opts.Repo = tempDir
+	repo, err := ReadRepo(opts)
+	rtest.OK(t, err)
+	rtest.Equals(t, tempDir, repo)
+
+	// test --repository-file option
+	foo := filepath.Join(tempDir, "foo")
+	err = ioutil.WriteFile(foo, []byte(tempDir+"\n"), 0666)
+	rtest.OK(t, err)
+
+	var opts2 GlobalOptions
+	opts2.RepositoryFile = foo
+	repo, err = ReadRepo(opts2)
+	rtest.OK(t, err)
+	rtest.Equals(t, tempDir, repo)
+
+	var opts3 GlobalOptions
+	opts3.RepositoryFile = foo + "-invalid"
+	repo, err = ReadRepo(opts3)
+	if err == nil {
+		t.Fatal("must not read repository path from invalid file path")
+	}
+}

doc/030_preparing_a_new_repo.rst

@@ -22,8 +22,10 @@ other options. You can skip to the next chapter once you've read the relevant
 section here.
 
 For automated backups, restic accepts the repository location in the
-environment variable ``RESTIC_REPOSITORY``. For the password, several options
-exist:
+environment variable ``RESTIC_REPOSITORY``. Restic can also read the repository
+location from a file specified via the ``--repository-file`` option or the
+environment variable ``RESTIC_REPOSITORY_FILE``. For the password, several
+options exist:
 
  * Setting the environment variable ``RESTIC_PASSWORD``
 

doc/040_backup.rst

@@ -407,6 +407,7 @@ environment variables. The following lists these environment variables:
 
 .. code-block:: console
 
+    RESTIC_REPOSITORY_FILE              Name of file containing the repository location (replaces --repository-file)
     RESTIC_REPOSITORY                   Location of repository (replaces -r)
     RESTIC_PASSWORD_FILE                Location of password file (replaces --password-file)
     RESTIC_PASSWORD                     The actual password for the repository

doc/manual_rest.rst

@@ -60,6 +60,7 @@ Usage help is available:
       -p, --password-file file         file to read the repository password from (default: $RESTIC_PASSWORD_FILE)
       -q, --quiet                      do not output comprehensive progress report
       -r, --repo repository            repository to backup to or restore from (default: $RESTIC_REPOSITORY)
+          --repository-file file       file to read the repository location from (default: $RESTIC_REPOSITORY_FILE)
           --tls-client-cert file       path to a file containing PEM encoded TLS client certificate and private key
       -v, --verbose n                  be verbose (specify --verbose multiple times or level --verbose=n)
 
@@ -92,6 +93,7 @@ command:
           --exclude-caches                         excludes cache directories that are marked with a CACHEDIR.TAG file. See https://bford.info/cachedir/ for the Cache Directory Tagging Standard
           --exclude-file file                      read exclude patterns from a file (can be specified multiple times)
           --exclude-if-present filename[:header]   takes filename[:header], exclude contents of directories containing filename (except filename itself) if header of that file is as provided (can be specified multiple times)
+          --exclude-larger-than size               max size of the files to be backed up (allowed suffixes: k/K, m/M, g/G, t/T)
           --files-from file                        read the files to backup from file (can be combined with file args/can be specified multiple times)
       -f, --force                                  force re-reading the target files/directories (overrides the "parent" flag)
       -h, --help                                   help for backup
@@ -122,6 +124,7 @@ command:
       -p, --password-file file         file to read the repository password from (default: $RESTIC_PASSWORD_FILE)
       -q, --quiet                      do not output comprehensive progress report
       -r, --repo repository            repository to backup to or restore from (default: $RESTIC_REPOSITORY)
+          --repository-file file       file to read the repository location from (default: $RESTIC_REPOSITORY_FILE)
           --tls-client-cert file       path to a file containing PEM encoded TLS client certificate and private key
       -v, --verbose n                  be verbose (specify --verbose multiple times or level --verbose=n)