Add path interposer
This will allow us to track (and eventually limit) the commands that the
build references via $PATH. These are mostly implicit dependencies on
the host system -- for Linux, we assume something similar to Ubuntu
14.04 with a few extra packages, but this will let us better define
that.
This will not catch uses of tools with absolute paths (/bin/bash, etc),
but most uses shouldn't be relying on absolute path names anyways.
Adds ~400ms on the first startup, ~140ms on subsequent runs, and
overhead of a few ms for every forwarded execution.
Test: m
Test: build/soong/build_test.bash
Test: Add `gcc --version`, TEMPORARY_DISABLE_PATH_RESTRICTIONS=true m
Change-Id: Id68cbb1c8ceef65bbbb10751e83722c7662d2351
diff --git a/cmd/path_interposer/Android.bp b/cmd/path_interposer/Android.bp
new file mode 100644
index 0000000..41a219f
--- /dev/null
+++ b/cmd/path_interposer/Android.bp
@@ -0,0 +1,20 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// 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.
+
+blueprint_go_binary {
+ name: "path_interposer",
+ deps: ["soong-ui-build-paths"],
+ srcs: ["main.go"],
+ testSrcs: ["main_test.go"],
+}
diff --git a/cmd/path_interposer/main.go b/cmd/path_interposer/main.go
new file mode 100644
index 0000000..01fe5d4
--- /dev/null
+++ b/cmd/path_interposer/main.go
@@ -0,0 +1,229 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// 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 main
+
+import (
+ "bytes"
+ "fmt"
+ "io"
+ "io/ioutil"
+ "os"
+ "os/exec"
+ "path/filepath"
+ "strconv"
+ "syscall"
+
+ "android/soong/ui/build/paths"
+)
+
+func main() {
+ interposer, err := os.Executable()
+ if err != nil {
+ fmt.Fprintln(os.Stderr, "Unable to locate interposer executable:", err)
+ os.Exit(1)
+ }
+
+ disableError := false
+ if e, ok := os.LookupEnv("TEMPORARY_DISABLE_PATH_RESTRICTIONS"); ok {
+ disableError = e == "1" || e == "y" || e == "yes" || e == "on" || e == "true"
+ }
+
+ exitCode, err := Main(os.Stdout, os.Stderr, interposer, os.Args, mainOpts{
+ disableError: disableError,
+
+ sendLog: paths.SendLog,
+ config: paths.GetConfig,
+ lookupParents: lookupParents,
+ })
+ if err != nil {
+ fmt.Fprintln(os.Stderr, err.Error())
+ }
+ os.Exit(exitCode)
+}
+
+var usage = fmt.Errorf(`To use the PATH interposer:
+ * Write the original PATH variable to <interposer>_origpath
+ * Set up a directory of symlinks to the PATH interposer, and use that in PATH
+
+If a tool isn't in the allowed list, a log will be posted to the unix domain
+socket at <interposer>_log.`)
+
+type mainOpts struct {
+ disableError bool
+
+ sendLog func(logSocket string, entry *paths.LogEntry, done chan interface{})
+ config func(name string) paths.PathConfig
+ lookupParents func() []paths.LogProcess
+}
+
+func Main(stdout, stderr io.Writer, interposer string, args []string, opts mainOpts) (int, error) {
+ base := filepath.Base(args[0])
+
+ origPathFile := interposer + "_origpath"
+ if base == filepath.Base(interposer) {
+ return 1, usage
+ }
+
+ origPath, err := ioutil.ReadFile(origPathFile)
+ if err != nil {
+ if os.IsNotExist(err) {
+ return 1, usage
+ } else {
+ return 1, fmt.Errorf("Failed to read original PATH: %v", err)
+ }
+ }
+
+ cmd := &exec.Cmd{
+ Args: args,
+ Env: os.Environ(),
+
+ Stdin: os.Stdin,
+ Stdout: stdout,
+ Stderr: stderr,
+ }
+
+ if err := os.Setenv("PATH", string(origPath)); err != nil {
+ return 1, fmt.Errorf("Failed to set PATH env: %v", err)
+ }
+
+ if config := opts.config(base); config.Log || config.Error {
+ var procs []paths.LogProcess
+ if opts.lookupParents != nil {
+ procs = opts.lookupParents()
+ }
+
+ if opts.sendLog != nil {
+ waitForLog := make(chan interface{})
+ opts.sendLog(interposer+"_log", &paths.LogEntry{
+ Basename: base,
+ Args: args,
+ Parents: procs,
+ }, waitForLog)
+ defer func() { <-waitForLog }()
+ }
+ if config.Error && !opts.disableError {
+ return 1, fmt.Errorf("%q is not allowed to be used. See https://android.googlesource.com/platform/build/+/master/Changes.md#PATH_Tools for more information.", base)
+ }
+ }
+
+ cmd.Path, err = exec.LookPath(base)
+ if err != nil {
+ return 1, err
+ }
+
+ if err = cmd.Run(); err != nil {
+ if exitErr, ok := err.(*exec.ExitError); ok {
+ if status, ok := exitErr.Sys().(syscall.WaitStatus); ok {
+ if status.Exited() {
+ return status.ExitStatus(), nil
+ } else if status.Signaled() {
+ exitCode := 128 + int(status.Signal())
+ return exitCode, nil
+ } else {
+ return 1, exitErr
+ }
+ } else {
+ return 1, nil
+ }
+ }
+ }
+
+ return 0, nil
+}
+
+type procEntry struct {
+ Pid int
+ Ppid int
+ Command string
+}
+
+func readProcs() map[int]procEntry {
+ cmd := exec.Command("ps", "-o", "pid,ppid,command")
+ data, err := cmd.Output()
+ if err != nil {
+ return nil
+ }
+
+ return parseProcs(data)
+}
+
+func parseProcs(data []byte) map[int]procEntry {
+ lines := bytes.Split(data, []byte("\n"))
+ if len(lines) < 2 {
+ return nil
+ }
+ // Remove the header
+ lines = lines[1:]
+
+ ret := make(map[int]procEntry, len(lines))
+ for _, line := range lines {
+ fields := bytes.SplitN(line, []byte(" "), 2)
+ if len(fields) != 2 {
+ continue
+ }
+
+ pid, err := strconv.Atoi(string(fields[0]))
+ if err != nil {
+ continue
+ }
+
+ line = bytes.TrimLeft(fields[1], " ")
+
+ fields = bytes.SplitN(line, []byte(" "), 2)
+ if len(fields) != 2 {
+ continue
+ }
+
+ ppid, err := strconv.Atoi(string(fields[0]))
+ if err != nil {
+ continue
+ }
+
+ ret[pid] = procEntry{
+ Pid: pid,
+ Ppid: ppid,
+ Command: string(bytes.TrimLeft(fields[1], " ")),
+ }
+ }
+
+ return ret
+}
+
+func lookupParents() []paths.LogProcess {
+ procs := readProcs()
+ if procs == nil {
+ return nil
+ }
+
+ list := []paths.LogProcess{}
+ pid := os.Getpid()
+ for {
+ entry, ok := procs[pid]
+ if !ok {
+ break
+ }
+
+ list = append([]paths.LogProcess{
+ {
+ Pid: pid,
+ Command: entry.Command,
+ },
+ }, list...)
+
+ pid = entry.Ppid
+ }
+
+ return list
+}
diff --git a/cmd/path_interposer/main_test.go b/cmd/path_interposer/main_test.go
new file mode 100644
index 0000000..4b25c44
--- /dev/null
+++ b/cmd/path_interposer/main_test.go
@@ -0,0 +1,196 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// 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 main
+
+import (
+ "fmt"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+ "testing"
+
+ "android/soong/ui/build/paths"
+)
+
+var tmpDir string
+var origPATH string
+
+func TestMain(m *testing.M) {
+ os.Exit(func() int {
+ var err error
+ tmpDir, err = ioutil.TempDir("", "interposer_test")
+ if err != nil {
+ panic(err)
+ }
+ defer os.RemoveAll(tmpDir)
+
+ origPATH = os.Getenv("PATH")
+ err = os.Setenv("PATH", "")
+ if err != nil {
+ panic(err)
+ }
+
+ return m.Run()
+ }())
+}
+
+func setup(t *testing.T) string {
+ f, err := ioutil.TempFile(tmpDir, "interposer")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer f.Close()
+
+ err = ioutil.WriteFile(f.Name()+"_origpath", []byte(origPATH), 0666)
+ if err != nil {
+ t.Fatal(err)
+ }
+ return f.Name()
+}
+
+func TestInterposer(t *testing.T) {
+ interposer := setup(t)
+
+ logConfig := func(name string) paths.PathConfig {
+ if name == "true" {
+ return paths.PathConfig{
+ Log: false,
+ Error: false,
+ }
+ } else if name == "path_interposer_test_not_allowed" {
+ return paths.PathConfig{
+ Log: false,
+ Error: true,
+ }
+ }
+ return paths.PathConfig{
+ Log: true,
+ Error: false,
+ }
+ }
+
+ testCases := []struct {
+ name string
+ args []string
+
+ exitCode int
+ err error
+ logEntry string
+ }{
+ {
+ name: "direct call",
+ args: []string{interposer},
+
+ exitCode: 1,
+ err: usage,
+ },
+ {
+ name: "relative call",
+ args: []string{filepath.Base(interposer)},
+
+ exitCode: 1,
+ err: usage,
+ },
+ {
+ name: "true",
+ args: []string{"/my/path/true"},
+ },
+ {
+ name: "relative true",
+ args: []string{"true"},
+ },
+ {
+ name: "exit code",
+ args: []string{"bash", "-c", "exit 42"},
+
+ exitCode: 42,
+ logEntry: "bash",
+ },
+ {
+ name: "signal",
+ args: []string{"bash", "-c", "kill -9 $$"},
+
+ exitCode: 137,
+ logEntry: "bash",
+ },
+ {
+ name: "does not exist",
+ args: []string{"path_interposer_test_does_not_exist"},
+
+ exitCode: 1,
+ err: fmt.Errorf(`exec: "path_interposer_test_does_not_exist": executable file not found in $PATH`),
+ logEntry: "path_interposer_test_does_not_exist",
+ },
+ {
+ name: "not allowed",
+ args: []string{"path_interposer_test_not_allowed"},
+
+ exitCode: 1,
+ err: fmt.Errorf(`"path_interposer_test_not_allowed" is not allowed to be used. See https://android.googlesource.com/platform/build/+/master/Changes.md#PATH_Tools for more information.`),
+ logEntry: "path_interposer_test_not_allowed",
+ },
+ }
+
+ for _, testCase := range testCases {
+ t.Run(testCase.name, func(t *testing.T) {
+ logged := false
+ logFunc := func(logSocket string, entry *paths.LogEntry, done chan interface{}) {
+ defer close(done)
+
+ logged = true
+ if entry.Basename != testCase.logEntry {
+ t.Errorf("unexpected log entry:\nwant: %q\n got: %q", testCase.logEntry, entry.Basename)
+ }
+ }
+
+ exitCode, err := Main(ioutil.Discard, ioutil.Discard, interposer, testCase.args, mainOpts{
+ sendLog: logFunc,
+ config: logConfig,
+ })
+
+ errstr := func(err error) string {
+ if err == nil {
+ return ""
+ }
+ return err.Error()
+ }
+ if errstr(testCase.err) != errstr(err) {
+ t.Errorf("unexpected error:\nwant: %v\n got: %v", testCase.err, err)
+ }
+ if testCase.exitCode != exitCode {
+ t.Errorf("expected exit code %d, got %d", testCase.exitCode, exitCode)
+ }
+ if !logged && testCase.logEntry != "" {
+ t.Errorf("no log entry, but expected %q", testCase.logEntry)
+ }
+ })
+ }
+}
+
+func TestMissingPath(t *testing.T) {
+ interposer := setup(t)
+ err := os.Remove(interposer + "_origpath")
+ if err != nil {
+ t.Fatalf("Failed to remove:", err)
+ }
+
+ exitCode, err := Main(ioutil.Discard, ioutil.Discard, interposer, []string{"true"}, mainOpts{})
+ if err != usage {
+ t.Errorf("Unexpected error:\n got: %v\nwant: %v", err, usage)
+ }
+ if exitCode != 1 {
+ t.Errorf("expected exit code %d, got %d", 1, exitCode)
+ }
+}
diff --git a/python/scripts/stub_template_host.txt b/python/scripts/stub_template_host.txt
index b90a28b..386298e 100644
--- a/python/scripts/stub_template_host.txt
+++ b/python/scripts/stub_template_host.txt
@@ -18,8 +18,6 @@
for directory in search_path:
if directory == '': continue
path = os.path.join(directory, name)
- if os.path.islink(path):
- path = os.path.realpath(path)
# Check if path is actual executable file.
if os.path.isfile(path) and os.access(path, os.X_OK):
return path
diff --git a/ui/build/Android.bp b/ui/build/Android.bp
index 5809894..1fe5b6f 100644
--- a/ui/build/Android.bp
+++ b/ui/build/Android.bp
@@ -13,9 +13,22 @@
// limitations under the License.
bootstrap_go_package {
+ name: "soong-ui-build-paths",
+ pkgPath: "android/soong/ui/build/paths",
+ srcs: [
+ "paths/config.go",
+ "paths/logs.go",
+ ],
+ testSrcs: [
+ "paths/logs_test.go",
+ ],
+}
+
+bootstrap_go_package {
name: "soong-ui-build",
pkgPath: "android/soong/ui/build",
deps: [
+ "soong-ui-build-paths",
"soong-ui-logger",
"soong-ui-tracer",
"soong-shared",
@@ -33,6 +46,7 @@
"finder.go",
"kati.go",
"ninja.go",
+ "path.go",
"proc_sync.go",
"signal.go",
"soong.go",
diff --git a/ui/build/build.go b/ui/build/build.go
index 78eb6a3..66dbf03 100644
--- a/ui/build/build.go
+++ b/ui/build/build.go
@@ -140,6 +140,8 @@
ensureEmptyDirectoriesExist(ctx, config.TempDir())
+ SetupPath(ctx, config)
+
if what&BuildProductConfig != 0 {
// Run make for product config
runMakeProductConfig(ctx, config)
diff --git a/ui/build/config.go b/ui/build/config.go
index 5622dff..6f2d24a 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -51,6 +51,8 @@
targetDeviceDir string
brokenDupRules bool
+
+ pathReplaced bool
}
const srcDirFileCheck = "build/soong/root.bp"
diff --git a/ui/build/path.go b/ui/build/path.go
new file mode 100644
index 0000000..52658ef
--- /dev/null
+++ b/ui/build/path.go
@@ -0,0 +1,149 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// 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 build
+
+import (
+ "fmt"
+ "io/ioutil"
+ "os"
+ "path/filepath"
+ "strings"
+
+ "github.com/google/blueprint/microfactory"
+
+ "android/soong/ui/build/paths"
+)
+
+func parsePathDir(dir string) []string {
+ f, err := os.Open(dir)
+ if err != nil {
+ return nil
+ }
+ defer f.Close()
+
+ if s, err := f.Stat(); err != nil || !s.IsDir() {
+ return nil
+ }
+
+ infos, err := f.Readdir(-1)
+ if err != nil {
+ return nil
+ }
+
+ ret := make([]string, 0, len(infos))
+ for _, info := range infos {
+ if m := info.Mode(); !m.IsDir() && m&0111 != 0 {
+ ret = append(ret, info.Name())
+ }
+ }
+ return ret
+}
+
+func SetupPath(ctx Context, config Config) {
+ if config.pathReplaced {
+ return
+ }
+
+ ctx.BeginTrace("path")
+ defer ctx.EndTrace()
+
+ origPath, _ := config.Environment().Get("PATH")
+ myPath := filepath.Join(config.OutDir(), ".path")
+ interposer := myPath + "_interposer"
+
+ var cfg microfactory.Config
+ cfg.Map("android/soong", "build/soong")
+ cfg.TrimPath, _ = filepath.Abs(".")
+ if _, err := microfactory.Build(&cfg, interposer, "android/soong/cmd/path_interposer"); err != nil {
+ ctx.Fatalln("Failed to build path interposer:", err)
+ }
+
+ if err := ioutil.WriteFile(interposer+"_origpath", []byte(origPath), 0777); err != nil {
+ ctx.Fatalln("Failed to write original path:", err)
+ }
+
+ entries, err := paths.LogListener(ctx.Context, interposer+"_log")
+ if err != nil {
+ ctx.Fatalln("Failed to listen for path logs:", err)
+ }
+
+ go func() {
+ for log := range entries {
+ curPid := os.Getpid()
+ for i, proc := range log.Parents {
+ if proc.Pid == curPid {
+ log.Parents = log.Parents[i:]
+ break
+ }
+ }
+ procPrints := []string{
+ "See https://android.googlesource.com/platform/build/+/master/Changes.md#PATH_Tools for more information.",
+ }
+ if len(log.Parents) > 0 {
+ procPrints = append(procPrints, "Process tree:")
+ for i, proc := range log.Parents {
+ procPrints = append(procPrints, fmt.Sprintf("%s→ %s", strings.Repeat(" ", i), proc.Command))
+ }
+ }
+
+ config := paths.GetConfig(log.Basename)
+ if config.Error {
+ ctx.Printf("Disallowed PATH tool %q used: %#v", log.Basename, log.Args)
+ for _, line := range procPrints {
+ ctx.Println(line)
+ }
+ } else {
+ ctx.Verbosef("Unknown PATH tool %q used: %#v", log.Basename, log.Args)
+ for _, line := range procPrints {
+ ctx.Verboseln(line)
+ }
+ }
+ }
+ }()
+
+ ensureEmptyDirectoriesExist(ctx, myPath)
+
+ var execs []string
+ for _, pathEntry := range filepath.SplitList(origPath) {
+ if pathEntry == "" {
+ // Ignore the current directory
+ continue
+ }
+ // TODO(dwillemsen): remove path entries under TOP? or anything
+ // that looks like an android source dir? They won't exist on
+ // the build servers, since they're added by envsetup.sh.
+ // (Except for the JDK, which is configured in ui/build/config.go)
+
+ execs = append(execs, parsePathDir(pathEntry)...)
+ }
+
+ allowAllSymlinks := config.Environment().IsEnvTrue("TEMPORARY_DISABLE_PATH_RESTRICTIONS")
+ for _, name := range execs {
+ if !paths.GetConfig(name).Symlink && !allowAllSymlinks {
+ continue
+ }
+
+ err := os.Symlink("../.path_interposer", filepath.Join(myPath, name))
+ // Intentionally ignore existing files -- that means that we
+ // just created it, and the first one should win.
+ if err != nil && !os.IsExist(err) {
+ ctx.Fatalln("Failed to create symlink:", err)
+ }
+ }
+
+ myPath, _ = filepath.Abs(myPath)
+ config.Environment().Set("PATH", myPath)
+ config.pathReplaced = true
+}
diff --git a/ui/build/paths/config.go b/ui/build/paths/config.go
new file mode 100644
index 0000000..ed44ced
--- /dev/null
+++ b/ui/build/paths/config.go
@@ -0,0 +1,150 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// 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 paths
+
+type PathConfig struct {
+ // Whether to create the symlink in the new PATH for this tool.
+ Symlink bool
+
+ // Whether to log about usages of this tool to the soong.log
+ Log bool
+
+ // Whether to exit with an error instead of invoking the underlying tool.
+ Error bool
+}
+
+var Allowed = PathConfig{
+ Symlink: true,
+ Log: false,
+ Error: false,
+}
+
+var Forbidden = PathConfig{
+ Symlink: false,
+ Log: true,
+ Error: true,
+}
+
+// The configuration used if the tool is not listed in the config below.
+// Currently this will create the symlink, but log a warning. In the future,
+// I expect this to move closer to Forbidden.
+var Missing = PathConfig{
+ Symlink: true,
+ Log: true,
+ Error: false,
+}
+
+func GetConfig(name string) PathConfig {
+ if config, ok := Configuration[name]; ok {
+ return config
+ }
+ return Missing
+}
+
+var Configuration = map[string]PathConfig{
+ "awk": Allowed,
+ "basename": Allowed,
+ "bash": Allowed,
+ "bzip2": Allowed,
+ "cat": Allowed,
+ "chmod": Allowed,
+ "cmp": Allowed,
+ "comm": Allowed,
+ "cp": Allowed,
+ "cut": Allowed,
+ "date": Allowed,
+ "dd": Allowed,
+ "diff": Allowed,
+ "dirname": Allowed,
+ "echo": Allowed,
+ "egrep": Allowed,
+ "env": Allowed,
+ "expr": Allowed,
+ "find": Allowed,
+ "getconf": Allowed,
+ "getopt": Allowed,
+ "git": Allowed,
+ "grep": Allowed,
+ "gzip": Allowed,
+ "head": Allowed,
+ "hexdump": Allowed,
+ "hostname": Allowed,
+ "jar": Allowed,
+ "java": Allowed,
+ "javap": Allowed,
+ "ln": Allowed,
+ "ls": Allowed,
+ "m4": Allowed,
+ "make": Allowed,
+ "md5sum": Allowed,
+ "mkdir": Allowed,
+ "mktemp": Allowed,
+ "mv": Allowed,
+ "openssl": Allowed,
+ "patch": Allowed,
+ "perl": Allowed,
+ "pstree": Allowed,
+ "python": Allowed,
+ "python2.7": Allowed,
+ "python3": Allowed,
+ "readlink": Allowed,
+ "realpath": Allowed,
+ "rm": Allowed,
+ "rsync": Allowed,
+ "runalarm": Allowed,
+ "sed": Allowed,
+ "setsid": Allowed,
+ "sh": Allowed,
+ "sha256sum": Allowed,
+ "sha512sum": Allowed,
+ "sort": Allowed,
+ "stat": Allowed,
+ "sum": Allowed,
+ "tar": Allowed,
+ "tail": Allowed,
+ "touch": Allowed,
+ "tr": Allowed,
+ "true": Allowed,
+ "uname": Allowed,
+ "uniq": Allowed,
+ "unzip": Allowed,
+ "wc": Allowed,
+ "which": Allowed,
+ "whoami": Allowed,
+ "xargs": Allowed,
+ "xmllint": Allowed,
+ "xz": Allowed,
+ "zip": Allowed,
+ "zipinfo": Allowed,
+
+ // Host toolchain is removed. In-tree toolchain should be used instead.
+ // GCC also can't find cc1 with this implementation.
+ "ar": Forbidden,
+ "as": Forbidden,
+ "cc": Forbidden,
+ "clang": Forbidden,
+ "clang++": Forbidden,
+ "gcc": Forbidden,
+ "g++": Forbidden,
+ "ld": Forbidden,
+ "ld.bfd": Forbidden,
+ "ld.gold": Forbidden,
+ "pkg-config": Forbidden,
+
+ // We've got prebuilts of these
+ //"dtc": Forbidden,
+ //"lz4": Forbidden,
+ //"lz4c": Forbidden,
+}
diff --git a/ui/build/paths/logs.go b/ui/build/paths/logs.go
new file mode 100644
index 0000000..a44994c
--- /dev/null
+++ b/ui/build/paths/logs.go
@@ -0,0 +1,101 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// 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 paths
+
+import (
+ "context"
+ "encoding/gob"
+ "net"
+ "os"
+ "time"
+)
+
+type LogProcess struct {
+ Pid int
+ Command string
+}
+
+type LogEntry struct {
+ Basename string
+ Args []string
+ Parents []LogProcess
+}
+
+const timeoutDuration = time.Duration(250) * time.Millisecond
+
+func SendLog(logSocket string, entry *LogEntry, done chan interface{}) {
+ defer close(done)
+
+ dialer := &net.Dialer{}
+ conn, err := dialer.Dial("unix", logSocket)
+ if err != nil {
+ return
+ }
+ defer conn.Close()
+
+ if err := conn.SetDeadline(dialer.Deadline); err != nil {
+ return
+ }
+
+ enc := gob.NewEncoder(conn)
+ enc.Encode(entry)
+}
+
+func LogListener(ctx context.Context, logSocket string) (chan *LogEntry, error) {
+ ret := make(chan *LogEntry, 5)
+
+ if err := os.Remove(logSocket); err != nil && !os.IsNotExist(err) {
+ return nil, err
+ }
+
+ ln, err := net.Listen("unix", logSocket)
+ if err != nil {
+ return nil, err
+ }
+
+ go func() {
+ for {
+ select {
+ case <-ctx.Done():
+ ln.Close()
+ }
+ }
+ }()
+
+ go func() {
+ defer close(ret)
+
+ for {
+ conn, err := ln.Accept()
+ if err != nil {
+ ln.Close()
+ break
+ }
+ conn.SetDeadline(time.Now().Add(timeoutDuration))
+
+ go func() {
+ defer conn.Close()
+
+ dec := gob.NewDecoder(conn)
+ entry := &LogEntry{}
+ if err := dec.Decode(entry); err != nil {
+ return
+ }
+ ret <- entry
+ }()
+ }
+ }()
+ return ret, nil
+}
diff --git a/ui/build/paths/logs_test.go b/ui/build/paths/logs_test.go
new file mode 100644
index 0000000..1ec040d
--- /dev/null
+++ b/ui/build/paths/logs_test.go
@@ -0,0 +1,134 @@
+// Copyright 2018 Google Inc. All rights reserved.
+//
+// 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 paths
+
+import (
+ "context"
+ "io/ioutil"
+ "net"
+ "os"
+ "path/filepath"
+ "reflect"
+ "strings"
+ "testing"
+ "time"
+)
+
+func TestSendLog(t *testing.T) {
+ d, err := ioutil.TempDir("", "log_socket")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer os.RemoveAll(d)
+ f := filepath.Join(d, "sock")
+
+ ctx, _ := context.WithTimeout(context.Background(), 2*timeoutDuration)
+
+ recv, err := LogListener(ctx, f)
+ if err != nil {
+ t.Fatal(err)
+ }
+
+ go func() {
+ for i := 0; i < 10; i++ {
+ SendLog(f, &LogEntry{
+ Basename: "test",
+ Args: []string{"foo", "bar"},
+ }, make(chan interface{}))
+ }
+ }()
+
+ count := 0
+ for {
+ select {
+ case entry := <-recv:
+ ref := LogEntry{
+ Basename: "test",
+ Args: []string{"foo", "bar"},
+ }
+ if !reflect.DeepEqual(ref, *entry) {
+ t.Fatalf("Bad log entry: %v", entry)
+ }
+ count++
+
+ if count == 10 {
+ return
+ }
+ case <-ctx.Done():
+ t.Error("Hit timeout before receiving all logs")
+ }
+ }
+}
+
+func TestSendLogError(t *testing.T) {
+ d, err := ioutil.TempDir("", "log_socket")
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer os.RemoveAll(d)
+
+ t.Run("Missing file", func(t *testing.T) {
+ start := time.Now()
+ SendLog(filepath.Join(d, "missing"), &LogEntry{}, make(chan interface{}))
+ elapsed := time.Since(start)
+ if elapsed > timeoutDuration {
+ t.Errorf("Should have been << timeout (%s), but was %s", timeoutDuration, elapsed)
+ }
+ })
+
+ t.Run("Regular file", func(t *testing.T) {
+ f := filepath.Join(d, "file")
+ if fp, err := os.Create(f); err == nil {
+ fp.Close()
+ } else {
+ t.Fatal(err)
+ }
+
+ start := time.Now()
+ SendLog(f, &LogEntry{}, make(chan interface{}))
+ elapsed := time.Since(start)
+ if elapsed > timeoutDuration {
+ t.Errorf("Should have been << timeout (%s), but was %s", timeoutDuration, elapsed)
+ }
+ })
+
+ t.Run("Reader not reading", func(t *testing.T) {
+ f := filepath.Join(d, "sock1")
+
+ ln, err := net.Listen("unix", f)
+ if err != nil {
+ t.Fatal(err)
+ }
+ defer ln.Close()
+
+ done := make(chan bool, 1)
+ go func() {
+ for i := 0; i < 1000; i++ {
+ SendLog(f, &LogEntry{
+ // Ensure a relatively large payload
+ Basename: strings.Repeat(" ", 100000),
+ }, make(chan interface{}))
+ }
+ done <- true
+ }()
+
+ select {
+ case <-done:
+ break
+ case <-time.After(10 * timeoutDuration):
+ t.Error("Should have finished")
+ }
+ })
+}