add default apparmor profile

Signed-off-by: Xianglin Gao <xlgao@zju.edu.cn>

server/apparmor/aaparser.go

@@ -0,0 +1,87 @@
+package apparmor
+
+import (
+	"fmt"
+	"os/exec"
+	"strconv"
+	"strings"
+)
+
+const (
+	binary = "apparmor_parser"
+)
+
+// GetVersion returns the major and minor version of apparmor_parser.
+func GetVersion() (int, error) {
+	output, err := cmd("", "--version")
+	if err != nil {
+		return -1, err
+	}
+
+	return parseVersion(output)
+}
+
+// LoadProfile runs `apparmor_parser -r` on a specified apparmor profile to
+// replace the profile.
+func LoadProfile(profilePath string) error {
+	_, err := cmd("", "-r", profilePath)
+	return err
+}
+
+// cmd runs `apparmor_parser` with the passed arguments.
+func cmd(dir string, arg ...string) (string, error) {
+	c := exec.Command(binary, arg...)
+	c.Dir = dir
+
+	output, err := c.CombinedOutput()
+	if err != nil {
+		return "", fmt.Errorf("running `%s %s` failed with output: %s\nerror: %v", c.Path, strings.Join(c.Args, " "), string(output), err)
+	}
+
+	return string(output), nil
+}
+
+// parseVersion takes the output from `apparmor_parser --version` and returns
+// a representation of the {major, minor, patch} version as a single number of
+// the form MMmmPPP {major, minor, patch}.
+func parseVersion(output string) (int, error) {
+	// output is in the form of the following:
+	// AppArmor parser version 2.9.1
+	// Copyright (C) 1999-2008 Novell Inc.
+	// Copyright 2009-2012 Canonical Ltd.
+
+	lines := strings.SplitN(output, "\n", 2)
+	words := strings.Split(lines[0], " ")
+	version := words[len(words)-1]
+
+	// 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)
+	}
+
+	// Default the versions to 0.
+	var majorVersion, minorVersion, patchLevel int
+
+	majorVersion, err := strconv.Atoi(v[0])
+	if err != nil {
+		return -1, err
+	}
+
+	if len(v) > 1 {
+		minorVersion, err = strconv.Atoi(v[1])
+		if err != nil {
+			return -1, err
+		}
+	}
+	if len(v) > 2 {
+		patchLevel, err = strconv.Atoi(v[2])
+		if err != nil {
+			return -1, err
+		}
+	}
+
+	// major*10^5 + minor*10^3 + patch*10^0
+	numericVersion := majorVersion*1e5 + minorVersion*1e3 + patchLevel
+	return numericVersion, nil
+}

server/apparmor/apparmor.go

@@ -0,0 +1,164 @@
+package apparmor
+
+import (
+	"bufio"
+	"io"
+	"io/ioutil"
+	"os"
+	"path"
+	"strings"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/docker/docker/utils/templates"
+	"github.com/opencontainers/runc/libcontainer/apparmor"
+)
+
+const (
+	// defaultApparmorProfile is the name of default apparmor profile name.
+	defaultApparmorProfile = "crio-default"
+
+	// profileDirectory is the file store for apparmor profiles and macros.
+	profileDirectory = "/etc/apparmor.d"
+
+	// ContainerAnnotationKeyPrefix is the prefix to an annotation key specifying a container profile.
+	ContainerAnnotationKeyPrefix = "container.apparmor.security.beta.kubernetes.io/"
+
+	// ProfileRuntimeDefault is he profile specifying the runtime default.
+	ProfileRuntimeDefault = "runtime/default"
+	// ProfileNamePrefix is the prefix for specifying profiles loaded on the node.
+	ProfileNamePrefix = "localhost/"
+)
+
+// profileData holds information about the given profile for generation.
+type profileData struct {
+	// Name is profile name.
+	Name string
+	// Imports defines the apparmor functions to import, before defining the profile.
+	Imports []string
+	// InnerImports defines the apparmor functions to import in the profile.
+	InnerImports []string
+	// Version is the {major, minor, patch} version of apparmor_parser as a single number.
+	Version int
+}
+
+// InstallDefaultAppArmorProfile installs default apparmor profile.
+func InstallDefaultAppArmorProfile() {
+	if err := InstallDefault(defaultApparmorProfile); err != nil {
+		// Allow daemon to run if loading failed, but are active
+		// (possibly through another run, manually, or via system startup)
+		if err := IsLoaded(defaultApparmorProfile); err != nil {
+			logrus.Errorf("AppArmor enabled on system but the %s profile could not be loaded.", defaultApparmorProfile)
+		}
+	}
+}
+
+// IsEnabled returns true if apparmor is enabled for the host.
+func IsEnabled() bool {
+	return apparmor.IsEnabled()
+}
+
+// GetAppArmorProfileName gets the profile name for the given container.
+func GetAppArmorProfileName(annotations map[string]string, ctrName string) string {
+	profile := GetProfileNameFromPodAnnotations(annotations, ctrName)
+
+	if profile == "" {
+		return ""
+	}
+
+	if profile == ProfileRuntimeDefault {
+		// If the value is runtime/default, then return default profile.
+		logrus.Infof("get default profile name")
+		return defaultApparmorProfile
+	}
+
+	profileName := strings.TrimPrefix(profile, ProfileNamePrefix)
+	return profileName
+}
+
+// GetProfileNameFromPodAnnotations gets the name of the profile to use with container from
+// pod annotations
+func GetProfileNameFromPodAnnotations(annotations map[string]string, containerName string) string {
+	return annotations[ContainerAnnotationKeyPrefix+containerName]
+}
+
+// InstallDefault generates a default profile in a temp directory determined by
+// os.TempDir(), then loads the profile into the kernel using 'apparmor_parser'.
+func InstallDefault(name string) error {
+	p := profileData{
+		Name: name,
+	}
+
+	// Install to a temporary directory.
+	f, err := ioutil.TempFile("", name)
+	if err != nil {
+		return err
+	}
+	profilePath := f.Name()
+
+	defer f.Close()
+
+	if err := p.generateDefault(f); err != nil {
+		return err
+	}
+
+	if err := LoadProfile(profilePath); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// IsLoaded checks if a passed profile has been loaded into the kernel.
+func IsLoaded(name string) error {
+	file, err := os.Open("/sys/kernel/security/apparmor/profiles")
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	r := bufio.NewReader(file)
+	for {
+		p, err := r.ReadString('\n')
+		if err != nil {
+			return err
+		}
+		if strings.HasPrefix(p, name+" ") {
+			return nil
+		}
+	}
+}
+
+// generateDefault creates an apparmor profile from ProfileData.
+func (p *profileData) generateDefault(out io.Writer) error {
+	compiled, err := templates.NewParse("apparmor_profile", baseTemplate)
+	if err != nil {
+		return err
+	}
+
+	if macroExists("tunables/global") {
+		p.Imports = append(p.Imports, "#include <tunables/global>")
+	} else {
+		p.Imports = append(p.Imports, "@{PROC}=/proc/")
+	}
+
+	if macroExists("abstractions/base") {
+		p.InnerImports = append(p.InnerImports, "#include <abstractions/base>")
+	}
+
+	ver, err := GetVersion()
+	if err != nil {
+		return err
+	}
+	p.Version = ver
+
+	if err := compiled.Execute(out, p); err != nil {
+		return err
+	}
+	return nil
+}
+
+// macrosExists checks if the passed macro exists.
+func macroExists(m string) bool {
+	_, err := os.Stat(path.Join(profileDirectory, m))
+	return err == nil
+}

server/apparmor/template.go

@@ -0,0 +1,43 @@
+package apparmor
+
+// baseTemplate defines the default apparmor profile for containers.
+const baseTemplate = `
+{{range $value := .Imports}}
+{{$value}}
+{{end}}
+
+profile {{.Name}} flags=(attach_disconnected,mediate_deleted) {
+{{range $value := .InnerImports}}
+  {{$value}}
+{{end}}
+
+  network,
+  capability,
+  file,
+  umount,
+
+  deny @{PROC}/* w,   # deny write for all files directly in /proc (not in a subdir)
+  # deny write to files not in /proc/<number>/** or /proc/sys/**
+  deny @{PROC}/{[^1-9],[^1-9][^0-9],[^1-9s][^0-9y][^0-9s],[^1-9][^0-9][^0-9][^0-9]*}/** w,
+  deny @{PROC}/sys/[^k]** w,  # deny /proc/sys except /proc/sys/k* (effectively /proc/sys/kernel)
+  deny @{PROC}/sys/kernel/{?,??,[^s][^h][^m]**} w,  # deny everything except shm* in /proc/sys/kernel/
+  deny @{PROC}/sysrq-trigger rwklx,
+  deny @{PROC}/mem rwklx,
+  deny @{PROC}/kmem rwklx,
+  deny @{PROC}/kcore rwklx,
+
+  deny mount,
+
+  deny /sys/[^f]*/** wklx,
+  deny /sys/f[^s]*/** wklx,
+  deny /sys/fs/[^c]*/** wklx,
+  deny /sys/fs/c[^g]*/** wklx,
+  deny /sys/fs/cg[^r]*/** wklx,
+  deny /sys/firmware/** rwklx,
+  deny /sys/kernel/security/** rwklx,
+
+{{if ge .Version 208095}}
+  ptrace (trace,read) peer={{.Name}},
+{{end}}
+}
+`

server/container_create.go

@@ -12,6 +12,7 @@ import (
 	"github.com/Sirupsen/logrus"
 	"github.com/docker/docker/pkg/stringid"
 	"github.com/kubernetes-incubator/cri-o/oci"
+	"github.com/kubernetes-incubator/cri-o/server/apparmor"
 	"github.com/kubernetes-incubator/cri-o/server/seccomp"
 	"github.com/kubernetes-incubator/cri-o/utils"
 	"github.com/opencontainers/runc/libcontainer/label"
@@ -184,10 +185,12 @@ func (s *Server) createSandboxContainer(containerID string, containerName string
 	}
 
 	// set this container's apparmor profile if it is set by sandbox
-	appArmorProfileName := GetAppArmorProfileName(sb.annotations, metadata.GetName())
+	if s.appArmorEnabled {
+		appArmorProfileName := apparmor.GetAppArmorProfileName(sb.annotations, metadata.GetName())
 		if appArmorProfileName != "" {
 			specgen.SetProcessApparmorProfile(appArmorProfileName)
 		}
+	}
 
 	if containerConfig.GetLinux().GetSecurityContext().GetPrivileged() {
 		specgen.SetupPrivileged(true)

server/server.go

@@ -13,6 +13,7 @@ import (
 	"github.com/docker/docker/pkg/registrar"
 	"github.com/docker/docker/pkg/truncindex"
 	"github.com/kubernetes-incubator/cri-o/oci"
+	"github.com/kubernetes-incubator/cri-o/server/apparmor"
 	"github.com/kubernetes-incubator/cri-o/server/seccomp"
 	"github.com/kubernetes-incubator/cri-o/utils"
 	"github.com/opencontainers/runc/libcontainer/label"
@@ -39,6 +40,8 @@ type Server struct {
 
 	seccompEnabled bool
 	seccompProfile seccomp.Seccomp
+
+	appArmorEnabled bool
 }
 
 func (s *Server) loadContainer(id string) error {
@@ -282,6 +285,7 @@ func New(config *Config) (*Server, error) {
 			containers: containers,
 		},
 		seccompEnabled:  seccompEnabled(),
+		appArmorEnabled: apparmor.IsEnabled(),
 	}
 	seccompProfile, err := ioutil.ReadFile(config.SeccompProfile)
 	if err != nil {
@@ -293,6 +297,10 @@ func New(config *Config) (*Server, error) {
 	}
 	s.seccompProfile = seccompConfig
 
+	if s.appArmorEnabled {
+		apparmor.InstallDefaultAppArmorProfile()
+	}
+
 	s.podIDIndex = truncindex.NewTruncIndex([]string{})
 	s.podNameIndex = registrar.NewRegistrar()
 	s.ctrIDIndex = truncindex.NewTruncIndex([]string{})

server/utils.go

@@ -11,14 +11,6 @@ const (
 	// According to http://man7.org/linux/man-pages/man5/resolv.conf.5.html:
 	// "The search list is currently limited to six domains with a total of 256 characters."
 	maxDNSSearches = 6
-
-	// ContainerAnnotationKeyPrefix is the prefix to an annotation key specifying a container profile.
-	ContainerAnnotationKeyPrefix = "container.apparmor.security.beta.kubernetes.io/"
-
-	// ProfileRuntimeDefault is he profile specifying the runtime default.
-	ProfileRuntimeDefault = "runtime/default"
-	// ProfileNamePrefix is the prefix for specifying profiles loaded on the node.
-	ProfileNamePrefix = "localhost/"
 )
 
 func int64Ptr(i int64) *int64 {
@@ -164,21 +156,3 @@ func SysctlsFromPodAnnotation(annotation string) ([]Sysctl, error) {
 	}
 	return sysctls, nil
 }
-
-// GetAppArmorProfileName gets the profile name for the given container.
-func GetAppArmorProfileName(annotations map[string]string, ctrName string) string {
-	profile := GetProfileNameFromPodAnnotations(annotations, ctrName)
-	if profile == "" || profile == ProfileRuntimeDefault {
-		// If the value is runtime/default, then it is equivalent to not specifying a profile.
-		return ""
-	}
-
-	profileName := strings.TrimPrefix(profile, ProfileNamePrefix)
-	return profileName
-}
-
-// GetProfileNameFromPodAnnotations gets the name of the profile to use with container from
-// pod annotations
-func GetProfileNameFromPodAnnotations(annotations map[string]string, containerName string) string {
-	return annotations[ContainerAnnotationKeyPrefix+containerName]
-}

vendor/src/github.com/docker/docker/utils/templates/templates.go

@@ -0,0 +1,42 @@
+package templates
+
+import (
+	"encoding/json"
+	"strings"
+	"text/template"
+)
+
+// basicFunctions are the set of initial
+// functions provided to every template.
+var basicFunctions = template.FuncMap{
+	"json": func(v interface{}) string {
+		a, _ := json.Marshal(v)
+		return string(a)
+	},
+	"split": strings.Split,
+	"join":  strings.Join,
+	"title": strings.Title,
+	"lower": strings.ToLower,
+	"upper": strings.ToUpper,
+	"pad":   padWithSpace,
+}
+
+// Parse creates a new annonymous template with the basic functions
+// and parses the given format.
+func Parse(format string) (*template.Template, error) {
+	return NewParse("", format)
+}
+
+// NewParse creates a new tagged template with the basic functions
+// and parses the given format.
+func NewParse(tag, format string) (*template.Template, error) {
+	return template.New(tag).Funcs(basicFunctions).Parse(format)
+}
+
+// padWithSpace adds whitespace to the input if the input is non-empty
+func padWithSpace(source string, prefix, suffix int) string {
+	if source == "" {
+		return source
+	}
+	return strings.Repeat(" ", prefix) + source + strings.Repeat(" ", suffix)
+}

vendor/src/github.com/opencontainers/runc/libcontainer/apparmor/apparmor.go

@@ -0,0 +1,39 @@
+// +build apparmor,linux
+
+package apparmor
+
+// #cgo LDFLAGS: -lapparmor
+// #include <sys/apparmor.h>
+// #include <stdlib.h>
+import "C"
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"unsafe"
+)
+
+// IsEnabled returns true if apparmor is enabled for the host.
+func IsEnabled() bool {
+	if _, err := os.Stat("/sys/kernel/security/apparmor"); err == nil && os.Getenv("container") == "" {
+		if _, err = os.Stat("/sbin/apparmor_parser"); err == nil {
+			buf, err := ioutil.ReadFile("/sys/module/apparmor/parameters/enabled")
+			return err == nil && len(buf) > 1 && buf[0] == 'Y'
+		}
+	}
+	return false
+}
+
+// ApplyProfile will apply the profile with the specified name to the process after
+// the next exec.
+func ApplyProfile(name string) error {
+	if name == "" {
+		return nil
+	}
+	cName := C.CString(name)
+	defer C.free(unsafe.Pointer(cName))
+	if _, err := C.aa_change_onexec(cName); err != nil {
+		return fmt.Errorf("apparmor failed to apply profile: %s", err)
+	}
+	return nil
+}

vendor/src/github.com/opencontainers/runc/libcontainer/apparmor/apparmor_disabled.go

@@ -0,0 +1,20 @@
+// +build !apparmor !linux
+
+package apparmor
+
+import (
+	"errors"
+)
+
+var ErrApparmorNotEnabled = errors.New("apparmor: config provided but apparmor not supported")
+
+func IsEnabled() bool {
+	return false
+}
+
+func ApplyProfile(name string) error {
+	if name != "" {
+		return ErrApparmorNotEnabled
+	}
+	return nil
+}