change default docker-engine profile to a template based on apparmor_parser version

Signed-off-by: Jessica Frazelle <acidburn@docker.com>

contrib/apparmor/main.go

@@ -0,0 +1,85 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+	"path"
+	"strconv"
+	"strings"
+	"text/template"
+)
+
+type profileData struct {
+	MajorVersion int
+	MinorVersion int
+}
+
+func main() {
+	if len(os.Args) < 2 {
+		log.Fatal("pass a filename to save the profile in.")
+	}
+
+	// parse the arg
+	apparmorProfilePath := os.Args[1]
+
+	// get the apparmor_version version
+	cmd := exec.Command("/sbin/apparmor_parser", "--version")
+
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		log.Fatalf("getting apparmor_parser version failed: %s (%s)", err, output)
+	}
+
+	// parse the version from the output
+	// 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(string(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) < 2 {
+		log.Fatalf("parsing major minor version failed for %q", version)
+	}
+
+	majorVersion, err := strconv.Atoi(v[0])
+	if err != nil {
+		log.Fatal(err)
+	}
+	minorVersion, err := strconv.Atoi(v[1])
+	if err != nil {
+		log.Fatal(err)
+	}
+	data := profileData{
+		MajorVersion: majorVersion,
+		MinorVersion: minorVersion,
+	}
+	fmt.Printf("apparmor_parser is of version %+v\n", data)
+
+	// parse the template
+	compiled, err := template.New("apparmor_profile").Parse(dockerProfileTemplate)
+	if err != nil {
+		log.Fatalf("parsing template failed: %v", err)
+	}
+
+	// make sure /etc/apparmor.d exists
+	if err := os.MkdirAll(path.Dir(apparmorProfilePath), 0755); err != nil {
+		log.Fatal(err)
+	}
+
+	f, err := os.OpenFile(apparmorProfilePath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer f.Close()
+
+	if err := compiled.Execute(f, data); err != nil {
+		log.Fatalf("executing template failed: %v", err)
+	}
+
+	fmt.Printf("created apparmor profile for version %+v at %q\n", data, apparmorProfilePath)
+}

contrib/apparmor/template.go

@@ -1,4 +1,6 @@
-@{DOCKER_GRAPH_PATH}=/var/lib/docker
+package main
+
+const dockerProfileTemplate = `@{DOCKER_GRAPH_PATH}=/var/lib/docker
 
 profile /usr/bin/docker (attach_disconnected, complain) {
   # Prevent following links to these files during container setup.
@@ -15,9 +17,11 @@ profile /usr/bin/docker (attach_disconnected, complain) {
 
   umount,
   pivot_root,
+{{if ge .MajorVersion 2}}{{if ge .MinorVersion 9}}
   signal (receive) peer=@{profile_name},
   signal (receive) peer=unconfined,
   signal (send),
+{{end}}{{end}}
   ipc rw,
   network,
   capability,
@@ -34,10 +38,12 @@ profile /usr/bin/docker (attach_disconnected, complain) {
   /etc/localtime r,
   /etc/ld.so.cache r,
 
+{{if ge .MajorVersion 2}}{{if ge .MinorVersion 9}}
   ptrace peer=@{profile_name},
   ptrace (read) peer=docker-default,
   deny ptrace (trace) peer=docker-default,
   deny ptrace peer=/usr/bin/docker///bin/ps,
+{{end}}{{end}}
 
   /usr/lib/** rm,
   /lib/** rm,
@@ -57,9 +63,11 @@ profile /usr/bin/docker (attach_disconnected, complain) {
   /sbin/zfs rCx,
   /sbin/apparmor_parser rCx,
 
+{{if ge .MajorVersion 2}}{{if ge .MinorVersion 9}}
   # Transitions
   change_profile -> docker-*,
   change_profile -> unconfined,
+{{end}}{{end}}
 
   profile /bin/cat (complain) {
     /etc/ld.so.cache r,
@@ -81,8 +89,10 @@ profile /usr/bin/docker (attach_disconnected, complain) {
     /dev/null rw,
     /bin/ps mr,
 
+{{if ge .MajorVersion 2}}{{if ge .MinorVersion 9}}
     # We don't need ptrace so we'll deny and ignore the error.
     deny ptrace (read, trace),
+{{end}}{{end}}
 
     # Quiet dac_override denials
     deny capability dac_override,
@@ -100,11 +110,15 @@ profile /usr/bin/docker (attach_disconnected, complain) {
     /proc/tty/drivers r,
   }
   profile /sbin/iptables (complain) {
+{{if ge .MajorVersion 2}}{{if ge .MinorVersion 9}}
     signal (receive) peer=/usr/bin/docker,
+{{end}}{{end}}
     capability net_admin,
   }
   profile /sbin/auplink flags=(attach_disconnected, complain) {
+{{if ge .MajorVersion 2}}{{if ge .MinorVersion 9}}
     signal (receive) peer=/usr/bin/docker,
+{{end}}{{end}}
     capability sys_admin,
     capability dac_override,
 
@@ -123,7 +137,9 @@ profile /usr/bin/docker (attach_disconnected, complain) {
     /proc/[0-9]*/mounts rw,
   }
   profile /sbin/modprobe /bin/kmod (complain) {
+{{if ge .MajorVersion 2}}{{if ge .MinorVersion 9}}
     signal (receive) peer=/usr/bin/docker,
+{{end}}{{end}}
     capability sys_module,
     /etc/ld.so.cache r,
     /lib/** rm,
@@ -137,7 +153,9 @@ profile /usr/bin/docker (attach_disconnected, complain) {
   }
   # xz works via pipes, so we do not need access to the filesystem.
   profile /usr/bin/xz (complain) {
+{{if ge .MajorVersion 2}}{{if ge .MinorVersion 9}}
     signal (receive) peer=/usr/bin/docker,
+{{end}}{{end}}
     /etc/ld.so.cache r,
     /lib/** rm,
     /usr/bin/xz rm,
@@ -238,4 +256,4 @@ profile /usr/bin/docker (attach_disconnected, complain) {
 
     capability mac_admin,
   }
-}
+}`