wip

ecs-init/apparmor/apparmor.go

@@ -0,0 +1,81 @@
+package apparmor
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+const (
+	ECSDefaultProfileName = "ecs-default"
+	appArmorProfileDir    = "/etc/apparmor.d"
+)
+
+const ecsDefaultProfile = `
+#include <tunables/global>
+
+profile ecs-default flags=(attach_disconnected,mediate_deleted) {
+  #include <abstractions/base>
+
+  network,
+  capability,
+  file,
+  umount,
+  # Host (privileged) processes may send signals to container processes.
+  signal (receive) peer=unconfined,
+  # Container processes may send signals amongst themselves.
+  signal (send,receive) peer=ecs-default,
+
+  # ECS agent requires DBUS send
+  dbus (send) bus=system,
+
+  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}/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,
+
+  # suppress ptrace denials when using 'docker ps' or using 'ps' inside a container
+  ptrace (trace,read,tracedby,readby) peer=ecs-default,
+}
+`
+
+// LoadDefaultProfile ensures the default profile to be loaded with the given name.
+// Returns nil error if the profile is already loaded.
+func LoadDefaultProfile(profileName string) error {
+	yes, err := isLoaded(profileName)
+	if err != nil {
+		return err
+	}
+	if yes {
+		return nil
+	}
+
+	f, err := os.Create(filepath.Join(appArmorProfileDir, profileName))
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	_, err = f.WriteString(ecsDefaultProfile)
+	if err != nil {
+		return err
+	}
+	path := f.Name()
+
+	if err := load(path); err != nil {
+		return fmt.Errorf("load apparmor profile %s: %w", path, err)
+	}
+	return nil
+}

ecs-init/apparmor/apparmor_utils.go

@@ -0,0 +1,68 @@
+/*
+   Copyright The docker Authors.
+   Copyright The Moby Authors.
+   Copyright The containerd Authors.
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package apparmor
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	exec "golang.org/x/sys/execabs"
+)
+
+// NOTE: This code is copied from <github.com/docker/docker/profiles/apparmor>.
+//       If you plan to make any changes, please make sure they are also sent
+//       upstream.
+
+func load(path string) error {
+	out, err := aaParser("-Kr", path)
+	if err != nil {
+		return fmt.Errorf("parser error(%q): %w", strings.TrimSpace(out), err)
+	}
+	return nil
+}
+
+func aaParser(args ...string) (string, error) {
+	out, err := exec.Command("apparmor_parser", args...).CombinedOutput()
+	return string(out), err
+}
+
+func isLoaded(name string) (bool, error) {
+	f, err := os.Open("/sys/kernel/security/apparmor/profiles")
+	if err != nil {
+		return false, err
+	}
+	defer f.Close()
+	r := bufio.NewReader(f)
+	for {
+		p, err := r.ReadString('\n')
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return false, err
+		}
+		if strings.HasPrefix(p, name+" ") {
+			return true, nil
+		}
+	}
+	return false, nil
+}

ecs-init/config/release.go

@@ -1,6 +1,3 @@
-//go:build !development
-// +build !development
-
 // Copyright 2015 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License"). You may

ecs-init/docker/docker_config.go

@@ -14,7 +14,11 @@
 package docker
 
 import (
+	"fmt"
+
+	"github.com/aws/amazon-ecs-agent/ecs-init/apparmor"
 	"github.com/aws/amazon-ecs-agent/ecs-init/config"
+	ctrdapparmor "github.com/containerd/containerd/pkg/apparmor"
 	godocker "github.com/fsouza/go-dockerclient"
 )
 
@@ -62,6 +66,10 @@ func createHostConfig(binds []string) *godocker.HostConfig {
 		Init:        true,
 	}
 
+	if ctrdapparmor.HostSupports() {
+		hostConfig.SecurityOpt = []string{fmt.Sprintf("apparmor:%s", apparmor.ECSDefaultProfileName)}
+	}
+
 	if config.RunPrivileged() {
 		hostConfig.Privileged = true
 	}

ecs-init/engine/engine.go

@@ -21,6 +21,7 @@ import (
 	"os"
 	"time"
 
+	"github.com/aws/amazon-ecs-agent/ecs-init/apparmor"
 	"github.com/aws/amazon-ecs-agent/ecs-init/backoff"
 	"github.com/aws/amazon-ecs-agent/ecs-init/cache"
 	"github.com/aws/amazon-ecs-agent/ecs-init/config"
@@ -31,6 +32,7 @@ import (
 	"github.com/aws/amazon-ecs-agent/ecs-init/gpu"
 
 	log "github.com/cihub/seelog"
+	ctrdapparmor "github.com/containerd/containerd/pkg/apparmor"
 )
 
 const (
@@ -113,6 +115,11 @@ func (e *Engine) PreStart() error {
 	if err != nil {
 		return err
 	}
+	// setup AppArmor if necessary
+	err = e.PreStartAppArmor()
+	if err != nil {
+		return err
+	}
 	// Enable use of loopback addresses for local routing purposes
 	log.Info("pre-start: enabling loopback routing")
 	err = e.loopbackRouting.Enable()
@@ -195,6 +202,16 @@ func (e *Engine) PreStartGPU() error {
 	return nil
 }
 
+// PreStartAppArmor sets up the ecs-default AppArmor profile if we're running
+// on an AppArmor-enabled system.
+func (e *Engine) PreStartAppArmor() error {
+	if ctrdapparmor.HostSupports() {
+		log.Infof("pre-start: setting up %s AppArmor profile", apparmor.ECSDefaultProfileName)
+		return apparmor.LoadDefaultProfile(apparmor.ECSDefaultProfileName)
+	}
+	return nil
+}
+
 // ReloadCache reloads the cached image of the ECS Agent into Docker
 func (e *Engine) ReloadCache() error {
 	docker, err := getDockerClient()

ecs-init/go.mod

@@ -6,17 +6,18 @@ require (
 	github.com/NVIDIA/gpu-monitoring-tools v0.0.0-20180829222009-86f2a9fac6c5
 	github.com/aws/aws-sdk-go v1.36.0
 	github.com/cihub/seelog v0.0.0-20170130134532-f561c5e57575
+	github.com/containerd/containerd v1.6.18
 	github.com/docker/go-plugins-helpers v0.0.0-20181025120712-1e6269c305b8
 	github.com/fsouza/go-dockerclient v0.0.0-20170830181106-98edf3edfae6
 	github.com/golang/mock v1.6.0
 	github.com/pkg/errors v0.9.1
 	github.com/stretchr/testify v1.7.0
+	golang.org/x/sys v0.6.0
 )
 
 require (
 	github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1 // indirect
 	github.com/Microsoft/go-winio v0.5.2 // indirect
-	github.com/containerd/containerd v1.6.18 // indirect
 	github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/docker/docker v23.0.3+incompatible // indirect
@@ -38,7 +39,6 @@ require (
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/sirupsen/logrus v1.8.1 // indirect
 	golang.org/x/net v0.8.0 // indirect
-	golang.org/x/sys v0.6.0 // indirect
 	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	gotest.tools/v3 v3.3.0 // indirect