From 83aebdd4e731777d9f8e55a233417bd1baff2e56 Mon Sep 17 00:00:00 2001 From: Antonio Murdaca Date: Tue, 21 Nov 2017 09:54:28 +0100 Subject: [PATCH] validate: add selinux smoke tests Signed-off-by: Antonio Murdaca --- pkg/framework/util.go | 10 +- pkg/validate/selinux.go | 138 ++++ vendor.conf | 1 + .../github.com/opencontainers/selinux/LICENSE | 201 ++++++ .../opencontainers/selinux/README.md | 7 + .../selinux/go-selinux/selinux.go | 593 ++++++++++++++++++ .../selinux/go-selinux/xattrs.go | 78 +++ 7 files changed, 1026 insertions(+), 2 deletions(-) create mode 100644 pkg/validate/selinux.go create mode 100644 vendor/github.com/opencontainers/selinux/LICENSE create mode 100644 vendor/github.com/opencontainers/selinux/README.md create mode 100644 vendor/github.com/opencontainers/selinux/go-selinux/selinux.go create mode 100644 vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go diff --git a/pkg/framework/util.go b/pkg/framework/util.go index 290485a264..abafa53d76 100644 --- a/pkg/framework/util.go +++ b/pkg/framework/util.go @@ -183,8 +183,8 @@ func CreateDefaultContainer(rc internalapi.RuntimeService, ic internalapi.ImageM return CreateContainer(rc, ic, containerConfig, podID, podConfig) } -// CreateContainer creates a container with the prefix of containerName. -func CreateContainer(rc internalapi.RuntimeService, ic internalapi.ImageManagerService, config *runtimeapi.ContainerConfig, podID string, podConfig *runtimeapi.PodSandboxConfig) string { +// CreateContainerWithError creates a container but leave error check to caller +func CreateContainerWithError(rc internalapi.RuntimeService, ic internalapi.ImageManagerService, config *runtimeapi.ContainerConfig, podID string, podConfig *runtimeapi.PodSandboxConfig) (string, error) { // Pull the image if it does not exist. imageName := config.Image.Image if !strings.Contains(imageName, ":") { @@ -199,6 +199,12 @@ func CreateContainer(rc internalapi.RuntimeService, ic internalapi.ImageManagerS By("Create container.") containerID, err := rc.CreateContainer(podID, config, podConfig) + return containerID, err +} + +// CreateContainer creates a container with the prefix of containerName. +func CreateContainer(rc internalapi.RuntimeService, ic internalapi.ImageManagerService, config *runtimeapi.ContainerConfig, podID string, podConfig *runtimeapi.PodSandboxConfig) string { + containerID, err := CreateContainerWithError(rc, ic, config, podID, podConfig) ExpectNoError(err, "failed to create container: %v", err) Logf("Created container %q\n", containerID) return containerID diff --git a/pkg/validate/selinux.go b/pkg/validate/selinux.go new file mode 100644 index 0000000000..6d80c135a0 --- /dev/null +++ b/pkg/validate/selinux.go @@ -0,0 +1,138 @@ +/* +Copyright 2017 The Kubernetes 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 validate + +import ( + "time" + + "github.com/kubernetes-incubator/cri-tools/pkg/framework" + "github.com/opencontainers/selinux/go-selinux" + internalapi "k8s.io/kubernetes/pkg/kubelet/apis/cri" + runtimeapi "k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1/runtime" + + . "github.com/onsi/ginkgo" + . "github.com/onsi/gomega" +) + +var _ = framework.KubeDescribe("SELinux", func() { + f := framework.NewDefaultCRIFramework() + + var rc internalapi.RuntimeService + var ic internalapi.ImageManagerService + + if selinux.GetEnabled() { + BeforeEach(func() { + rc = f.CRIClient.CRIRuntimeClient + ic = f.CRIClient.CRIImageClient + }) + + Context("runtime should support selinux", func() { + var sandboxID string + var sandboxConfig *runtimeapi.PodSandboxConfig + + BeforeEach(func() { + sandboxID, sandboxConfig = framework.CreatePodSandboxForContainer(rc) + }) + + AfterEach(func() { + By("stop PodSandbox") + rc.StopPodSandbox(sandboxID) + By("delete PodSandbox") + rc.RemovePodSandbox(sandboxID) + }) + + It("should work with just selinux level set", func() { + options := &runtimeapi.SELinuxOption{ + Level: "s0", + } + containerID := createContainerWithSelinux(rc, ic, sandboxID, sandboxConfig, options, true, true) + checkContainerSelinux(rc, containerID, true) + }) + + It("should work with selinux set", func() { + options := &runtimeapi.SELinuxOption{ + User: "system_u", + Role: "system_r", + Type: "svirt_lxc_net_t", + Level: "s0:c4,c5", + } + containerID := createContainerWithSelinux(rc, ic, sandboxID, sandboxConfig, options, true, true) + checkContainerSelinux(rc, containerID, true) + }) + + It("should error on create with wrong options", func() { + options := &runtimeapi.SELinuxOption{ + User: "system_u", + Role: "system_r", + Type: "svirt_lxc_net_t", + // s0,c4,c5 is wrong, should have been s0:c4,c5 + Level: "s0,c4,c5", + } + _ = createContainerWithSelinux(rc, ic, sandboxID, sandboxConfig, options, false, false) + }) + }) + } +}) + +func createContainerWithSelinux(rc internalapi.RuntimeService, ic internalapi.ImageManagerService, sandboxID string, sandboxConfig *runtimeapi.PodSandboxConfig, options *runtimeapi.SELinuxOption, shouldStart, shouldCreate bool) string { + By("create a container with selinux") + containerName := "selinux-test-" + framework.NewUUID() + containerConfig := &runtimeapi.ContainerConfig{ + Metadata: framework.BuildContainerMetadata(containerName, framework.DefaultAttempt), + Image: &runtimeapi.ImageSpec{Image: framework.DefaultContainerImage}, + Command: []string{"touch", "foo"}, + Linux: &runtimeapi.LinuxContainerConfig{ + SecurityContext: &runtimeapi.LinuxContainerSecurityContext{ + SelinuxOptions: options, + }, + }, + } + containerID, err := framework.CreateContainerWithError(rc, ic, containerConfig, sandboxID, sandboxConfig) + if !shouldCreate { + Expect(err).To(HaveOccurred()) + return "" + } + + Expect(err).NotTo(HaveOccurred()) + + By("start container with selinux") + err = rc.StartContainer(containerID) + if shouldStart { + Expect(err).NotTo(HaveOccurred()) + } else { + Expect(err).To(HaveOccurred()) + } + + // wait container exited and check the status. + Eventually(func() runtimeapi.ContainerState { + return getContainerStatus(rc, containerID).State + }, time.Minute, time.Second*4).Should(Equal(runtimeapi.ContainerState_CONTAINER_EXITED)) + + return containerID +} + +func checkContainerSelinux(rc internalapi.RuntimeService, containerID string, shoudRun bool) { + By("get container status") + status, err := rc.ContainerStatus(containerID) + Expect(err).NotTo(HaveOccurred()) + + if shoudRun { + Expect(status.GetExitCode()).To(Equal(int32(0))) + } else { + Expect(status.GetExitCode()).NotTo(Equal(int32(0))) + } +} diff --git a/vendor.conf b/vendor.conf index 711dc1ac46..b3c11bfe99 100644 --- a/vendor.conf +++ b/vendor.conf @@ -41,3 +41,4 @@ k8s.io/client-go 72e1c2a1ef30b3f8da039e92d4a6a1f079f374e8 k8s.io/kube-openapi 39a7bf85c140f972372c2a0d1ee40adbf0c8bfe1 k8s.io/kubernetes 3b4424ce8ca25b1effc5d9586b3b6727c15fde33 k8s.io/utils bf963466fd3fea33c428098b12a89d8ecd012f2 +github.com/opencontainers/selinux b29023b86e4a69d1b46b7e7b4e2b6fda03f0b9cd diff --git a/vendor/github.com/opencontainers/selinux/LICENSE b/vendor/github.com/opencontainers/selinux/LICENSE new file mode 100644 index 0000000000..8dada3edaf --- /dev/null +++ b/vendor/github.com/opencontainers/selinux/LICENSE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright {yyyy} {name of copyright owner} + + 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. diff --git a/vendor/github.com/opencontainers/selinux/README.md b/vendor/github.com/opencontainers/selinux/README.md new file mode 100644 index 0000000000..043a929371 --- /dev/null +++ b/vendor/github.com/opencontainers/selinux/README.md @@ -0,0 +1,7 @@ +# selinux + +[![GoDoc](https://godoc.org/github.com/opencontainers/selinux?status.svg)](https://godoc.org/github.com/opencontainers/selinux) [![Go Report Card](https://goreportcard.com/badge/github.com/opencontainers/selinux)](https://goreportcard.com/report/github.com/opencontainers/selinux) [![Build Status](https://travis-ci.org/opencontainers/selinux.svg?branch=master)](https://travis-ci.org/opencontainers/selinux) + +Common SELinux package used across the container ecosystem. + +Please see the [godoc](https://godoc.org/github.com/opencontainers/selinux) for more information. diff --git a/vendor/github.com/opencontainers/selinux/go-selinux/selinux.go b/vendor/github.com/opencontainers/selinux/go-selinux/selinux.go new file mode 100644 index 0000000000..de9316c2e2 --- /dev/null +++ b/vendor/github.com/opencontainers/selinux/go-selinux/selinux.go @@ -0,0 +1,593 @@ +// +build linux + +package selinux + +import ( + "bufio" + "crypto/rand" + "encoding/binary" + "fmt" + "io" + "os" + "path/filepath" + "regexp" + "strconv" + "strings" + "sync" + "syscall" +) + +const ( + // Enforcing constant indicate SELinux is in enforcing mode + Enforcing = 1 + // Permissive constant to indicate SELinux is in permissive mode + Permissive = 0 + // Disabled constant to indicate SELinux is disabled + Disabled = -1 + selinuxDir = "/etc/selinux/" + selinuxConfig = selinuxDir + "config" + selinuxTypeTag = "SELINUXTYPE" + selinuxTag = "SELINUX" + selinuxPath = "/sys/fs/selinux" + xattrNameSelinux = "security.selinux" + stRdOnly = 0x01 +) + +type selinuxState struct { + enabledSet bool + enabled bool + selinuxfsSet bool + selinuxfs string + mcsList map[string]bool + sync.Mutex +} + +var ( + assignRegex = regexp.MustCompile(`^([^=]+)=(.*)$`) + state = selinuxState{ + mcsList: make(map[string]bool), + } +) + +// Context is a representation of the SELinux label broken into 4 parts +type Context map[string]string + +func (s *selinuxState) setEnable(enabled bool) bool { + s.Lock() + defer s.Unlock() + s.enabledSet = true + s.enabled = enabled + return s.enabled +} + +func (s *selinuxState) getEnabled() bool { + s.Lock() + enabled := s.enabled + enabledSet := s.enabledSet + s.Unlock() + if enabledSet { + return enabled + } + + enabled = false + if fs := getSelinuxMountPoint(); fs != "" { + if con, _ := CurrentLabel(); con != "kernel" { + enabled = true + } + } + return s.setEnable(enabled) +} + +// SetDisabled disables selinux support for the package +func SetDisabled() { + state.setEnable(false) +} + +func (s *selinuxState) setSELinuxfs(selinuxfs string) string { + s.Lock() + defer s.Unlock() + s.selinuxfsSet = true + s.selinuxfs = selinuxfs + return s.selinuxfs +} + +func (s *selinuxState) getSELinuxfs() string { + s.Lock() + selinuxfs := s.selinuxfs + selinuxfsSet := s.selinuxfsSet + s.Unlock() + if selinuxfsSet { + return selinuxfs + } + + selinuxfs = "" + f, err := os.Open("/proc/self/mountinfo") + if err != nil { + return selinuxfs + } + defer f.Close() + + scanner := bufio.NewScanner(f) + for scanner.Scan() { + txt := scanner.Text() + // Safe as mountinfo encodes mountpoints with spaces as \040. + sepIdx := strings.Index(txt, " - ") + if sepIdx == -1 { + continue + } + if !strings.Contains(txt[sepIdx:], "selinuxfs") { + continue + } + fields := strings.Split(txt, " ") + if len(fields) < 5 { + continue + } + selinuxfs = fields[4] + break + } + + if selinuxfs != "" { + var buf syscall.Statfs_t + syscall.Statfs(selinuxfs, &buf) + if (buf.Flags & stRdOnly) == 1 { + selinuxfs = "" + } + } + return s.setSELinuxfs(selinuxfs) +} + +// getSelinuxMountPoint returns the path to the mountpoint of an selinuxfs +// filesystem or an empty string if no mountpoint is found. Selinuxfs is +// a proc-like pseudo-filesystem that exposes the selinux policy API to +// processes. The existence of an selinuxfs mount is used to determine +// whether selinux is currently enabled or not. +func getSelinuxMountPoint() string { + return state.getSELinuxfs() +} + +// GetEnabled returns whether selinux is currently enabled. +func GetEnabled() bool { + return state.getEnabled() +} + +func readConfig(target string) (value string) { + var ( + val, key string + bufin *bufio.Reader + ) + + in, err := os.Open(selinuxConfig) + if err != nil { + return "" + } + defer in.Close() + + bufin = bufio.NewReader(in) + + for done := false; !done; { + var line string + if line, err = bufin.ReadString('\n'); err != nil { + if err != io.EOF { + return "" + } + done = true + } + line = strings.TrimSpace(line) + if len(line) == 0 { + // Skip blank lines + continue + } + if line[0] == ';' || line[0] == '#' { + // Skip comments + continue + } + if groups := assignRegex.FindStringSubmatch(line); groups != nil { + key, val = strings.TrimSpace(groups[1]), strings.TrimSpace(groups[2]) + if key == target { + return strings.Trim(val, "\"") + } + } + } + return "" +} + +func getSELinuxPolicyRoot() string { + return selinuxDir + readConfig(selinuxTypeTag) +} + +func readCon(name string) (string, error) { + var val string + + in, err := os.Open(name) + if err != nil { + return "", err + } + defer in.Close() + + _, err = fmt.Fscanf(in, "%s", &val) + return val, err +} + +// SetFileLabel sets the SELinux label for this path or returns an error. +func SetFileLabel(path string, label string) error { + return lsetxattr(path, xattrNameSelinux, []byte(label), 0) +} + +// FileLabel returns the SELinux label for this path or returns an error. +func FileLabel(path string) (string, error) { + label, err := lgetxattr(path, xattrNameSelinux) + if err != nil { + return "", err + } + // Trim the NUL byte at the end of the byte buffer, if present. + if len(label) > 0 && label[len(label)-1] == '\x00' { + label = label[:len(label)-1] + } + return string(label), nil +} + +/* +SetFSCreateLabel tells kernel the label to create all file system objects +created by this task. Setting label="" to return to default. +*/ +func SetFSCreateLabel(label string) error { + return writeCon(fmt.Sprintf("/proc/self/task/%d/attr/fscreate", syscall.Gettid()), label) +} + +/* +FSCreateLabel returns the default label the kernel which the kernel is using +for file system objects created by this task. "" indicates default. +*/ +func FSCreateLabel() (string, error) { + return readCon(fmt.Sprintf("/proc/self/task/%d/attr/fscreate", syscall.Gettid())) +} + +// CurrentLabel returns the SELinux label of the current process thread, or an error. +func CurrentLabel() (string, error) { + return readCon(fmt.Sprintf("/proc/self/task/%d/attr/current", syscall.Gettid())) +} + +// PidLabel returns the SELinux label of the given pid, or an error. +func PidLabel(pid int) (string, error) { + return readCon(fmt.Sprintf("/proc/%d/attr/current", pid)) +} + +/* +ExecLabel returns the SELinux label that the kernel will use for any programs +that are executed by the current process thread, or an error. +*/ +func ExecLabel() (string, error) { + return readCon(fmt.Sprintf("/proc/self/task/%d/attr/exec", syscall.Gettid())) +} + +func writeCon(name string, val string) error { + out, err := os.OpenFile(name, os.O_WRONLY, 0) + if err != nil { + return err + } + defer out.Close() + + if val != "" { + _, err = out.Write([]byte(val)) + } else { + _, err = out.Write(nil) + } + return err +} + +/* +SetExecLabel sets the SELinux label that the kernel will use for any programs +that are executed by the current process thread, or an error. +*/ +func SetExecLabel(label string) error { + return writeCon(fmt.Sprintf("/proc/self/task/%d/attr/exec", syscall.Gettid()), label) +} + +// Get returns the Context as a string +func (c Context) Get() string { + return fmt.Sprintf("%s:%s:%s:%s", c["user"], c["role"], c["type"], c["level"]) +} + +// NewContext creates a new Context struct from the specified label +func NewContext(label string) Context { + c := make(Context) + + if len(label) != 0 { + con := strings.SplitN(label, ":", 4) + c["user"] = con[0] + c["role"] = con[1] + c["type"] = con[2] + c["level"] = con[3] + } + return c +} + +// ReserveLabel reserves the MLS/MCS level component of the specified label +func ReserveLabel(label string) { + if len(label) != 0 { + con := strings.SplitN(label, ":", 4) + mcsAdd(con[3]) + } +} + +func selinuxEnforcePath() string { + return fmt.Sprintf("%s/enforce", selinuxPath) +} + +// EnforceMode returns the current SELinux mode Enforcing, Permissive, Disabled +func EnforceMode() int { + var enforce int + + enforceS, err := readCon(selinuxEnforcePath()) + if err != nil { + return -1 + } + + enforce, err = strconv.Atoi(string(enforceS)) + if err != nil { + return -1 + } + return enforce +} + +/* +SetEnforceMode sets the current SELinux mode Enforcing, Permissive. +Disabled is not valid, since this needs to be set at boot time. +*/ +func SetEnforceMode(mode int) error { + return writeCon(selinuxEnforcePath(), fmt.Sprintf("%d", mode)) +} + +/* +DefaultEnforceMode returns the systems default SELinux mode Enforcing, +Permissive or Disabled. Note this is is just the default at boot time. +EnforceMode tells you the systems current mode. +*/ +func DefaultEnforceMode() int { + switch readConfig(selinuxTag) { + case "enforcing": + return Enforcing + case "permissive": + return Permissive + } + return Disabled +} + +func mcsAdd(mcs string) error { + state.Lock() + defer state.Unlock() + if state.mcsList[mcs] { + return fmt.Errorf("MCS Label already exists") + } + state.mcsList[mcs] = true + return nil +} + +func mcsDelete(mcs string) { + state.Lock() + defer state.Unlock() + state.mcsList[mcs] = false +} + +func intToMcs(id int, catRange uint32) string { + var ( + SETSIZE = int(catRange) + TIER = SETSIZE + ORD = id + ) + + if id < 1 || id > 523776 { + return "" + } + + for ORD > TIER { + ORD = ORD - TIER + TIER-- + } + TIER = SETSIZE - TIER + ORD = ORD + TIER + return fmt.Sprintf("s0:c%d,c%d", TIER, ORD) +} + +func uniqMcs(catRange uint32) string { + var ( + n uint32 + c1, c2 uint32 + mcs string + ) + + for { + binary.Read(rand.Reader, binary.LittleEndian, &n) + c1 = n % catRange + binary.Read(rand.Reader, binary.LittleEndian, &n) + c2 = n % catRange + if c1 == c2 { + continue + } else { + if c1 > c2 { + c1, c2 = c2, c1 + } + } + mcs = fmt.Sprintf("s0:c%d,c%d", c1, c2) + if err := mcsAdd(mcs); err != nil { + continue + } + break + } + return mcs +} + +/* +ReleaseLabel will unreserve the MLS/MCS Level field of the specified label. +Allowing it to be used by another process. +*/ +func ReleaseLabel(label string) { + if len(label) != 0 { + con := strings.SplitN(label, ":", 4) + mcsDelete(con[3]) + } +} + +var roFileLabel string + +// ROFileLabel returns the specified SELinux readonly file label +func ROFileLabel() (fileLabel string) { + return roFileLabel +} + +/* +ContainerLabels returns an allocated processLabel and fileLabel to be used for +container labeling by the calling process. +*/ +func ContainerLabels() (processLabel string, fileLabel string) { + var ( + val, key string + bufin *bufio.Reader + ) + + if !GetEnabled() { + return "", "" + } + lxcPath := fmt.Sprintf("%s/contexts/lxc_contexts", getSELinuxPolicyRoot()) + in, err := os.Open(lxcPath) + if err != nil { + return "", "" + } + defer in.Close() + + bufin = bufio.NewReader(in) + + for done := false; !done; { + var line string + if line, err = bufin.ReadString('\n'); err != nil { + if err == io.EOF { + done = true + } else { + goto exit + } + } + line = strings.TrimSpace(line) + if len(line) == 0 { + // Skip blank lines + continue + } + if line[0] == ';' || line[0] == '#' { + // Skip comments + continue + } + if groups := assignRegex.FindStringSubmatch(line); groups != nil { + key, val = strings.TrimSpace(groups[1]), strings.TrimSpace(groups[2]) + if key == "process" { + processLabel = strings.Trim(val, "\"") + } + if key == "file" { + fileLabel = strings.Trim(val, "\"") + } + if key == "ro_file" { + roFileLabel = strings.Trim(val, "\"") + } + } + } + + if processLabel == "" || fileLabel == "" { + return "", "" + } + + if roFileLabel == "" { + roFileLabel = fileLabel + } +exit: + mcs := uniqMcs(1024) + scon := NewContext(processLabel) + scon["level"] = mcs + processLabel = scon.Get() + scon = NewContext(fileLabel) + scon["level"] = mcs + fileLabel = scon.Get() + return processLabel, fileLabel +} + +// SecurityCheckContext validates that the SELinux label is understood by the kernel +func SecurityCheckContext(val string) error { + return writeCon(fmt.Sprintf("%s.context", selinuxPath), val) +} + +/* +CopyLevel returns a label with the MLS/MCS level from src label replaces on +the dest label. +*/ +func CopyLevel(src, dest string) (string, error) { + if src == "" { + return "", nil + } + if err := SecurityCheckContext(src); err != nil { + return "", err + } + if err := SecurityCheckContext(dest); err != nil { + return "", err + } + scon := NewContext(src) + tcon := NewContext(dest) + mcsDelete(tcon["level"]) + mcsAdd(scon["level"]) + tcon["level"] = scon["level"] + return tcon.Get(), nil +} + +// Prevent users from relabing system files +func badPrefix(fpath string) error { + var badprefixes = []string{"/usr"} + + for _, prefix := range badprefixes { + if fpath == prefix || strings.HasPrefix(fpath, fmt.Sprintf("%s/", prefix)) { + return fmt.Errorf("relabeling content in %s is not allowed", prefix) + } + } + return nil +} + +// Chcon changes the fpath file object to the SELinux label label. +// If the fpath is a directory and recurse is true Chcon will walk the +// directory tree setting the label +func Chcon(fpath string, label string, recurse bool) error { + if label == "" { + return nil + } + if err := badPrefix(fpath); err != nil { + return err + } + callback := func(p string, info os.FileInfo, err error) error { + return SetFileLabel(p, label) + } + + if recurse { + return filepath.Walk(fpath, callback) + } + + return SetFileLabel(fpath, label) +} + +// DupSecOpt takes an SELinux process label and returns security options that +// can will set the SELinux Type and Level for future container processes +func DupSecOpt(src string) []string { + if src == "" { + return nil + } + con := NewContext(src) + if con["user"] == "" || + con["role"] == "" || + con["type"] == "" || + con["level"] == "" { + return nil + } + return []string{"user:" + con["user"], + "role:" + con["role"], + "type:" + con["type"], + "level:" + con["level"]} +} + +// DisableSecOpt returns a security opt that can be used to disabling SELinux +// labeling support for future container processes +func DisableSecOpt() []string { + return []string{"disable"} +} diff --git a/vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go b/vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go new file mode 100644 index 0000000000..7f2ef85049 --- /dev/null +++ b/vendor/github.com/opencontainers/selinux/go-selinux/xattrs.go @@ -0,0 +1,78 @@ +// +build linux + +package selinux + +import ( + "syscall" + "unsafe" +) + +var _zero uintptr + +// Returns a []byte slice if the xattr is set and nil otherwise +// Requires path and its attribute as arguments +func lgetxattr(path string, attr string) ([]byte, error) { + var sz int + pathBytes, err := syscall.BytePtrFromString(path) + if err != nil { + return nil, err + } + attrBytes, err := syscall.BytePtrFromString(attr) + if err != nil { + return nil, err + } + + // Start with a 128 length byte array + sz = 128 + dest := make([]byte, sz) + destBytes := unsafe.Pointer(&dest[0]) + _sz, _, errno := syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(destBytes), uintptr(len(dest)), 0, 0) + + switch { + case errno == syscall.ENODATA: + return nil, errno + case errno == syscall.ENOTSUP: + return nil, errno + case errno == syscall.ERANGE: + // 128 byte array might just not be good enough, + // A dummy buffer is used ``uintptr(0)`` to get real size + // of the xattrs on disk + _sz, _, errno = syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(unsafe.Pointer(nil)), uintptr(0), 0, 0) + sz = int(_sz) + if sz < 0 { + return nil, errno + } + dest = make([]byte, sz) + destBytes := unsafe.Pointer(&dest[0]) + _sz, _, errno = syscall.Syscall6(syscall.SYS_LGETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(destBytes), uintptr(len(dest)), 0, 0) + if errno != 0 { + return nil, errno + } + case errno != 0: + return nil, errno + } + sz = int(_sz) + return dest[:sz], nil +} + +func lsetxattr(path string, attr string, data []byte, flags int) error { + pathBytes, err := syscall.BytePtrFromString(path) + if err != nil { + return err + } + attrBytes, err := syscall.BytePtrFromString(attr) + if err != nil { + return err + } + var dataBytes unsafe.Pointer + if len(data) > 0 { + dataBytes = unsafe.Pointer(&data[0]) + } else { + dataBytes = unsafe.Pointer(&_zero) + } + _, _, errno := syscall.Syscall6(syscall.SYS_LSETXATTR, uintptr(unsafe.Pointer(pathBytes)), uintptr(unsafe.Pointer(attrBytes)), uintptr(dataBytes), uintptr(len(data)), uintptr(flags), 0) + if errno != 0 { + return errno + } + return nil +}