Wrap AppArmor errors to provide more debug information

Mostly all AppArmor errors are now wrapped to provide additional context
to the user what actually went wrong. We now only use the spelling
`AppArmor` rather than `apparmor` to give the errors a uniform look.

Signed-off-by: Sascha Grunert <sgrunert@suse.com>

common/pkg/apparmor/apparmor.go

@@ -15,7 +15,6 @@ const (
 )
 
 var (
-
 	// ErrApparmorUnsupported indicates that AppArmor support is not supported.
 	ErrApparmorUnsupported = errors.New("AppArmor is not supported")
 	// ErrApparmorRootless indicates that AppArmor support is not supported in rootless mode.

common/pkg/apparmor/apparmor_linux.go

@@ -5,7 +5,6 @@ package apparmor
 import (
 	"bufio"
 	"bytes"
-	"fmt"
 	"io"
 	"os"
 	"os/exec"
@@ -47,7 +46,7 @@ type profileData struct {
 func (p *profileData) generateDefault(out io.Writer) error {
 	compiled, err := template.New("apparmor_profile").Parse(defaultProfileTemplate)
 	if err != nil {
-		return err
+		return errors.Wrap(err, "create AppArmor profile from template")
 	}
 
 	if macroExists("tunables/global") {
@@ -62,11 +61,11 @@ func (p *profileData) generateDefault(out io.Writer) error {
 
 	ver, err := getAAParserVersion()
 	if err != nil {
-		return err
+		return errors.Wrap(err, "get AppArmor version")
 	}
 	p.Version = ver
 
-	return compiled.Execute(out, p)
+	return errors.Wrap(compiled.Execute(out, p), "execute compiled profile")
 }
 
 // macrosExists checks if the passed macro exists.
@@ -89,28 +88,29 @@ func InstallDefault(name string) error {
 	cmd := exec.Command("apparmor_parser", "-Kr")
 	pipe, err := cmd.StdinPipe()
 	if err != nil {
-		return err
+		return errors.Wrap(err, "execute apparmor_parser")
 	}
 	if err := cmd.Start(); err != nil {
 		if pipeErr := pipe.Close(); pipeErr != nil {
-			logrus.Errorf("unable to close apparmor pipe: %q", pipeErr)
+			logrus.Errorf("unable to close AppArmor pipe: %q", pipeErr)
 		}
-		return err
+		return errors.Wrap(err, "start apparmor_parser command")
 	}
 	if err := p.generateDefault(pipe); err != nil {
 		if pipeErr := pipe.Close(); pipeErr != nil {
-			logrus.Errorf("unable to close apparmor pipe: %q", pipeErr)
+			logrus.Errorf("unable to close AppArmor pipe: %q", pipeErr)
 		}
 		if cmdErr := cmd.Wait(); cmdErr != nil {
-			logrus.Errorf("unable to wait for apparmor command: %q", cmdErr)
+			logrus.Errorf("unable to wait for AppArmor command: %q", cmdErr)
 		}
-		return err
+		return errors.Wrap(err, "generate default profile into pipe")
 	}
 
 	if pipeErr := pipe.Close(); pipeErr != nil {
-		logrus.Errorf("unable to close apparmor pipe: %q", pipeErr)
+		logrus.Errorf("unable to close AppArmor pipe: %q", pipeErr)
 	}
-	return cmd.Wait()
+
+	return errors.Wrap(cmd.Wait(), "wait for AppArmor command")
 }
 
 // DefaultContent returns the default profile content as byte slice. The
@@ -120,7 +120,7 @@ func DefaultContent(name string) ([]byte, error) {
 	p := profileData{Name: name}
 	var bytes bytes.Buffer
 	if err := p.generateDefault(&bytes); err != nil {
-		return nil, err
+		return nil, errors.Wrap(err, "generate default AppAmor profile")
 	}
 	return bytes.Bytes(), nil
 }
@@ -137,7 +137,7 @@ func IsLoaded(name string) (bool, error) {
 		if os.IsNotExist(err) {
 			return false, nil
 		}
-		return false, err
+		return false, errors.Wrap(err, "open AppArmor profile path")
 	}
 	defer file.Close()
 
@@ -148,7 +148,7 @@ func IsLoaded(name string) (bool, error) {
 			break
 		}
 		if err != nil {
-			return false, err
+			return false, errors.Wrap(err, "reading AppArmor profile")
 		}
 		if strings.HasPrefix(p, name+" ") {
 			return true, nil
@@ -165,7 +165,7 @@ func execAAParser(dir string, args ...string) (string, error) {
 
 	output, err := c.Output()
 	if err != nil {
-		return "", fmt.Errorf("running `%s %s` failed with output: %s\nerror: %v", c.Path, strings.Join(c.Args, " "), output, err)
+		return "", errors.Errorf("running `%s %s` failed with output: %s\nerror: %v", c.Path, strings.Join(c.Args, " "), output, err)
 	}
 
 	return string(output), nil
@@ -175,7 +175,7 @@ func execAAParser(dir string, args ...string) (string, error) {
 func getAAParserVersion() (int, error) {
 	output, err := execAAParser("", "--version")
 	if err != nil {
-		return -1, err
+		return -1, errors.Wrap(err, "execute apparmor_parser")
 	}
 	return parseAAParserVersion(output)
 }
@@ -194,7 +194,7 @@ func parseAAParserVersion(output string) (int, error) {
 	// split by major minor version
 	v := strings.Split(version, ".")
 	if len(v) == 0 || len(v) > 3 {
-		return -1, fmt.Errorf("parsing version failed for output: `%s`", output)
+		return -1, errors.Errorf("parsing version failed for output: `%s`", output)
 	}
 
 	// Default the versions to 0.
@@ -202,19 +202,19 @@ func parseAAParserVersion(output string) (int, error) {
 
 	majorVersion, err := strconv.Atoi(v[0])
 	if err != nil {
-		return -1, err
+		return -1, errors.Wrap(err, "convert AppArmor major version")
 	}
 
 	if len(v) > 1 {
 		minorVersion, err = strconv.Atoi(v[1])
 		if err != nil {
-			return -1, err
+			return -1, errors.Wrap(err, "convert AppArmor minor version")
 		}
 	}
 	if len(v) > 2 {
 		patchLevel, err = strconv.Atoi(v[2])
 		if err != nil {
-			return -1, err
+			return -1, errors.Wrap(err, "convert AppArmor patch version")
 		}
 	}
 
@@ -251,7 +251,7 @@ func CheckProfileAndLoadDefault(name string) (string, error) {
 		if name == "" {
 			return "", nil
 		} else {
-			return "", fmt.Errorf("profile %q specified but AppArmor is disabled on the host", name)
+			return "", errors.Errorf("profile %q specified but AppArmor is disabled on the host", name)
 		}
 	}
 
@@ -262,10 +262,10 @@ func CheckProfileAndLoadDefault(name string) (string, error) {
 		// name.
 		isLoaded, err := IsLoaded(name)
 		if err != nil {
-			return "", err
+			return "", errors.Wrapf(err, "verify if profile %s is loaded", name)
 		}
 		if !isLoaded {
-			return "", fmt.Errorf("AppArmor profile %q specified but not loaded", name)
+			return "", errors.Errorf("AppArmor profile %q specified but not loaded", name)
 		}
 		return name, nil
 	}
@@ -274,12 +274,12 @@ func CheckProfileAndLoadDefault(name string) (string, error) {
 	// if it's loaded before installing it.
 	isLoaded, err := IsLoaded(name)
 	if err != nil {
-		return "", err
+		return "", errors.Wrapf(err, "verify if profile %s is loaded", name)
 	}
 	if !isLoaded {
 		err = InstallDefault(name)
 		if err != nil {
-			return "", err
+			return "", errors.Wrapf(err, "install profile %s", name)
 		}
 		logrus.Infof("successfully loaded AppAmor profile %q", name)
 	} else {