interfaces: create directories for security files

This patch ensures that we have the right directory in the Setup method
of each of the four security backends. In the past we seemed to have
got a free ride on the old security code that did this for us.

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>

interfaces/apparmor/backend.go

@@ -40,6 +40,7 @@ package apparmor
 import (
 	"bytes"
 	"fmt"
+	"os"
 	"path/filepath"
 	"regexp"
 
@@ -89,7 +90,11 @@ func (b *Backend) Setup(snapInfo *snap.Info, developerMode bool, repo *interface
 		return fmt.Errorf("cannot obtain expected security files for snap %q: %s", snapName, err)
 	}
 	glob := interfaces.SecurityTagGlob(snapInfo.Name())
-	changed, removed, errEnsure := osutil.EnsureDirState(dirs.SnapAppArmorDir, glob, content)
+	dir := dirs.SnapAppArmorDir
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("cannot create directory for apparmor profiles %q: %s", dir, err)
+	}
+	changed, removed, errEnsure := osutil.EnsureDirState(dir, glob, content)
 	errReload := reloadProfiles(changed)
 	errUnload := unloadProfiles(removed)
 	if errEnsure != nil {

interfaces/dbus/backend.go

@@ -30,6 +30,7 @@ package dbus
 import (
 	"bytes"
 	"fmt"
+	"os"
 
 	"github.com/ubuntu-core/snappy/dirs"
 	"github.com/ubuntu-core/snappy/interfaces"
@@ -61,7 +62,11 @@ func (b *Backend) Setup(snapInfo *snap.Info, developerMode bool, repo *interface
 		return fmt.Errorf("cannot obtain expected DBus configuration files for snap %q: %s", snapName, err)
 	}
 	glob := fmt.Sprintf("%s.conf", interfaces.SecurityTagGlob(snapName))
-	_, _, err = osutil.EnsureDirState(dirs.SnapBusPolicyDir, glob, content)
+	dir := dirs.SnapBusPolicyDir
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("cannot create directory for DBus configuration files %q: %s", dir, err)
+	}
+	_, _, err = osutil.EnsureDirState(dir, glob, content)
 	if err != nil {
 		return fmt.Errorf("cannot synchronize DBus configuration files for snap %q: %s", snapName, err)
 	}

interfaces/seccomp/backend.go

@@ -35,6 +35,7 @@ package seccomp
 import (
 	"bytes"
 	"fmt"
+	"os"
 
 	"github.com/ubuntu-core/snappy/dirs"
 	"github.com/ubuntu-core/snappy/interfaces"
@@ -69,7 +70,11 @@ func (b *Backend) Setup(snapInfo *snap.Info, developerMode bool, repo *interface
 		return fmt.Errorf("cannot obtain expected security files for snap %q: %s", snapName, err)
 	}
 	glob := interfaces.SecurityTagGlob(snapName)
-	_, _, err = osutil.EnsureDirState(dirs.SnapSeccompDir, glob, content)
+	dir := dirs.SnapSeccompDir
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("cannot create directory for seccomp profiles %q: %s", dir, err)
+	}
+	_, _, err = osutil.EnsureDirState(dir, glob, content)
 	if err != nil {
 		return fmt.Errorf("cannot synchronize security files for snap %q: %s", snapName, err)
 	}

interfaces/udev/backend.go

@@ -27,6 +27,7 @@ package udev
 import (
 	"bytes"
 	"fmt"
+	"os"
 
 	"github.com/ubuntu-core/snappy/dirs"
 	"github.com/ubuntu-core/snappy/interfaces"
@@ -59,7 +60,11 @@ func (b *Backend) Setup(snapInfo *snap.Info, developerMode bool, repo *interface
 		return fmt.Errorf("cannot obtain expected udev rules for snap %q: %s", snapName, err)
 	}
 	glob := fmt.Sprintf("70-%s.rules", interfaces.SecurityTagGlob(snapName))
-	return ensureDirState(dirs.SnapUdevRulesDir, glob, content, snapName)
+	dir := dirs.SnapUdevRulesDir
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("cannot create directory for udev rules %q: %s", dir, err)
+	}
+	return ensureDirState(dir, glob, content, snapName)
 }
 
 // Remove removes udev rules specific to a given snap.