package utils import ( "bytes" "crypto/rand" "crypto/sha1" "crypto/sha256" "encoding/hex" "fmt" "io" "io/ioutil" "net/http" "os" "os/exec" "path/filepath" "regexp" "runtime" "strconv" "strings" "sync" "syscall" "github.com/docker/docker/dockerversion" "github.com/docker/docker/pkg/fileutils" "github.com/docker/docker/pkg/ioutils" "github.com/docker/docker/pkg/log" ) type KeyValuePair struct { Key string Value string } // Request a given URL and return an io.Reader func Download(url string) (resp *http.Response, err error) { if resp, err = http.Get(url); err != nil { return nil, err } if resp.StatusCode >= 400 { return nil, fmt.Errorf("Got HTTP status code >= 400: %s", resp.Status) } return resp, nil } func Trunc(s string, maxlen int) string { if len(s) <= maxlen { return s } return s[:maxlen] } // Figure out the absolute path of our own binary (if it's still around). func SelfPath() string { path, err := exec.LookPath(os.Args[0]) if err != nil { if os.IsNotExist(err) { return "" } if execErr, ok := err.(*exec.Error); ok && os.IsNotExist(execErr.Err) { return "" } panic(err) } path, err = filepath.Abs(path) if err != nil { if os.IsNotExist(err) { return "" } panic(err) } return path } func dockerInitSha1(target string) string { f, err := os.Open(target) if err != nil { return "" } defer f.Close() h := sha1.New() _, err = io.Copy(h, f) if err != nil { return "" } return hex.EncodeToString(h.Sum(nil)) } func isValidDockerInitPath(target string, selfPath string) bool { // target and selfPath should be absolute (InitPath and SelfPath already do this) if target == "" { return false } if dockerversion.IAMSTATIC { if selfPath == "" { return false } if target == selfPath { return true } targetFileInfo, err := os.Lstat(target) if err != nil { return false } selfPathFileInfo, err := os.Lstat(selfPath) if err != nil { return false } return os.SameFile(targetFileInfo, selfPathFileInfo) } return dockerversion.INITSHA1 != "" && dockerInitSha1(target) == dockerversion.INITSHA1 } // Figure out the path of our dockerinit (which may be SelfPath()) func DockerInitPath(localCopy string) string { selfPath := SelfPath() if isValidDockerInitPath(selfPath, selfPath) { // if we're valid, don't bother checking anything else return selfPath } var possibleInits = []string{ localCopy, dockerversion.INITPATH, filepath.Join(filepath.Dir(selfPath), "dockerinit"), // FHS 3.0 Draft: "/usr/libexec includes internal binaries that are not intended to be executed directly by users or shell scripts. Applications may use a single subdirectory under /usr/libexec." // http://www.linuxbase.org/betaspecs/fhs/fhs.html#usrlibexec "/usr/libexec/docker/dockerinit", "/usr/local/libexec/docker/dockerinit", // FHS 2.3: "/usr/lib includes object files, libraries, and internal binaries that are not intended to be executed directly by users or shell scripts." // http://refspecs.linuxfoundation.org/FHS_2.3/fhs-2.3.html#USRLIBLIBRARIESFORPROGRAMMINGANDPA "/usr/lib/docker/dockerinit", "/usr/local/lib/docker/dockerinit", } for _, dockerInit := range possibleInits { if dockerInit == "" { continue } path, err := exec.LookPath(dockerInit) if err == nil { path, err = filepath.Abs(path) if err != nil { // LookPath already validated that this file exists and is executable (following symlinks), so how could Abs fail? panic(err) } if isValidDockerInitPath(path, selfPath) { return path } } } return "" } func GetTotalUsedFds() int { if fds, err := ioutil.ReadDir(fmt.Sprintf("/proc/%d/fd", os.Getpid())); err != nil { log.Errorf("Error opening /proc/%d/fd: %s", os.Getpid(), err) } else { return len(fds) } return -1 } // TruncateID returns a shorthand version of a string identifier for convenience. // A collision with other shorthands is very unlikely, but possible. // In case of a collision a lookup with TruncIndex.Get() will fail, and the caller // will need to use a langer prefix, or the full-length Id. func TruncateID(id string) string { shortLen := 12 if len(id) < shortLen { shortLen = len(id) } return id[:shortLen] } // GenerateRandomID returns an unique id func GenerateRandomID() string { for { id := make([]byte, 32) if _, err := io.ReadFull(rand.Reader, id); err != nil { panic(err) // This shouldn't happen } value := hex.EncodeToString(id) // if we try to parse the truncated for as an int and we don't have // an error then the value is all numberic and causes issues when // used as a hostname. ref #3869 if _, err := strconv.ParseInt(TruncateID(value), 10, 64); err == nil { continue } return value } } func ValidateID(id string) error { if id == "" { return fmt.Errorf("Id can't be empty") } if strings.Contains(id, ":") { return fmt.Errorf("Invalid character in id: ':'") } return nil } // Code c/c from io.Copy() modified to handle escape sequence func CopyEscapable(dst io.Writer, src io.ReadCloser) (written int64, err error) { buf := make([]byte, 32*1024) for { nr, er := src.Read(buf) if nr > 0 { // ---- Docker addition // char 16 is C-p if nr == 1 && buf[0] == 16 { nr, er = src.Read(buf) // char 17 is C-q if nr == 1 && buf[0] == 17 { if err := src.Close(); err != nil { return 0, err } return 0, nil } } // ---- End of docker nw, ew := dst.Write(buf[0:nr]) if nw > 0 { written += int64(nw) } if ew != nil { err = ew break } if nr != nw { err = io.ErrShortWrite break } } if er == io.EOF { break } if er != nil { err = er break } } return written, err } func HashData(src io.Reader) (string, error) { h := sha256.New() if _, err := io.Copy(h, src); err != nil { return "", err } return "sha256:" + hex.EncodeToString(h.Sum(nil)), nil } // FIXME: this is deprecated by CopyWithTar in archive.go func CopyDirectory(source, dest string) error { if output, err := exec.Command("cp", "-ra", source, dest).CombinedOutput(); err != nil { return fmt.Errorf("Error copy: %s (%s)", err, output) } return nil } type WriteFlusher struct { sync.Mutex w io.Writer flusher http.Flusher } func (wf *WriteFlusher) Write(b []byte) (n int, err error) { wf.Lock() defer wf.Unlock() n, err = wf.w.Write(b) wf.flusher.Flush() return n, err } // Flush the stream immediately. func (wf *WriteFlusher) Flush() { wf.Lock() defer wf.Unlock() wf.flusher.Flush() } func NewWriteFlusher(w io.Writer) *WriteFlusher { var flusher http.Flusher if f, ok := w.(http.Flusher); ok { flusher = f } else { flusher = &ioutils.NopFlusher{} } return &WriteFlusher{w: w, flusher: flusher} } func NewHTTPRequestError(msg string, res *http.Response) error { return &JSONError{ Message: msg, Code: res.StatusCode, } } func IsURL(str string) bool { return strings.HasPrefix(str, "http://") || strings.HasPrefix(str, "https://") } func IsGIT(str string) bool { return strings.HasPrefix(str, "git://") || strings.HasPrefix(str, "github.com/") || strings.HasPrefix(str, "git@github.com:") || (strings.HasSuffix(str, ".git") && IsURL(str)) } var ( localHostRx = regexp.MustCompile(`(?m)^nameserver 127[^\n]+\n*`) ) // RemoveLocalDns looks into the /etc/resolv.conf, // and removes any local nameserver entries. func RemoveLocalDns(resolvConf []byte) []byte { return localHostRx.ReplaceAll(resolvConf, []byte{}) } // An StatusError reports an unsuccessful exit by a command. type StatusError struct { Status string StatusCode int } func (e *StatusError) Error() string { return fmt.Sprintf("Status: %s, Code: %d", e.Status, e.StatusCode) } func quote(word string, buf *bytes.Buffer) { // Bail out early for "simple" strings if word != "" && !strings.ContainsAny(word, "\\'\"`${[|&;<>()~*?! \t\n") { buf.WriteString(word) return } buf.WriteString("'") for i := 0; i < len(word); i++ { b := word[i] if b == '\'' { // Replace literal ' with a close ', a \', and a open ' buf.WriteString("'\\''") } else { buf.WriteByte(b) } } buf.WriteString("'") } // Take a list of strings and escape them so they will be handled right // when passed as arguments to an program via a shell func ShellQuoteArguments(args []string) string { var buf bytes.Buffer for i, arg := range args { if i != 0 { buf.WriteByte(' ') } quote(arg, &buf) } return buf.String() } var globalTestID string // TestDirectory creates a new temporary directory and returns its path. // The contents of directory at path `templateDir` is copied into the // new directory. func TestDirectory(templateDir string) (dir string, err error) { if globalTestID == "" { globalTestID = RandomString()[:4] } prefix := fmt.Sprintf("docker-test%s-%s-", globalTestID, GetCallerName(2)) if prefix == "" { prefix = "docker-test-" } dir, err = ioutil.TempDir("", prefix) if err = os.Remove(dir); err != nil { return } if templateDir != "" { if err = CopyDirectory(templateDir, dir); err != nil { return } } return } // GetCallerName introspects the call stack and returns the name of the // function `depth` levels down in the stack. func GetCallerName(depth int) string { // Use the caller function name as a prefix. // This helps trace temp directories back to their test. pc, _, _, _ := runtime.Caller(depth + 1) callerLongName := runtime.FuncForPC(pc).Name() parts := strings.Split(callerLongName, ".") callerShortName := parts[len(parts)-1] return callerShortName } func CopyFile(src, dst string) (int64, error) { if src == dst { return 0, nil } sf, err := os.Open(src) if err != nil { return 0, err } defer sf.Close() if err := os.Remove(dst); err != nil && !os.IsNotExist(err) { return 0, err } df, err := os.Create(dst) if err != nil { return 0, err } defer df.Close() return io.Copy(df, sf) } // ReplaceOrAppendValues returns the defaults with the overrides either // replaced by env key or appended to the list func ReplaceOrAppendEnvValues(defaults, overrides []string) []string { cache := make(map[string]int, len(defaults)) for i, e := range defaults { parts := strings.SplitN(e, "=", 2) cache[parts[0]] = i } for _, value := range overrides { parts := strings.SplitN(value, "=", 2) if i, exists := cache[parts[0]]; exists { defaults[i] = value } else { defaults = append(defaults, value) } } return defaults } // ReadSymlinkedDirectory returns the target directory of a symlink. // The target of the symbolic link may not be a file. func ReadSymlinkedDirectory(path string) (string, error) { var realPath string var err error if realPath, err = filepath.Abs(path); err != nil { return "", fmt.Errorf("unable to get absolute path for %s: %s", path, err) } if realPath, err = filepath.EvalSymlinks(realPath); err != nil { return "", fmt.Errorf("failed to canonicalise path for %s: %s", path, err) } realPathInfo, err := os.Stat(realPath) if err != nil { return "", fmt.Errorf("failed to stat target '%s' of '%s': %s", realPath, path, err) } if !realPathInfo.Mode().IsDir() { return "", fmt.Errorf("canonical path points to a file '%s'", realPath) } return realPath, nil } // TreeSize walks a directory tree and returns its total size in bytes. func TreeSize(dir string) (size int64, err error) { data := make(map[uint64]struct{}) err = filepath.Walk(dir, func(d string, fileInfo os.FileInfo, e error) error { // Ignore directory sizes if fileInfo == nil { return nil } s := fileInfo.Size() if fileInfo.IsDir() || s == 0 { return nil } // Check inode to handle hard links correctly inode := fileInfo.Sys().(*syscall.Stat_t).Ino // inode is not a uint64 on all platforms. Cast it to avoid issues. if _, exists := data[uint64(inode)]; exists { return nil } // inode is not a uint64 on all platforms. Cast it to avoid issues. data[uint64(inode)] = struct{}{} size += s return nil }) return } // ValidateContextDirectory checks if all the contents of the directory // can be read and returns an error if some files can't be read // symlinks which point to non-existing files don't trigger an error func ValidateContextDirectory(srcPath string, excludes []string) error { return filepath.Walk(filepath.Join(srcPath, "."), func(filePath string, f os.FileInfo, err error) error { // skip this directory/file if it's not in the path, it won't get added to the context if relFilePath, err := filepath.Rel(srcPath, filePath); err != nil { return err } else if skip, err := fileutils.Matches(relFilePath, excludes); err != nil { return err } else if skip { if f.IsDir() { return filepath.SkipDir } return nil } if err != nil { if os.IsPermission(err) { return fmt.Errorf("can't stat '%s'", filePath) } if os.IsNotExist(err) { return nil } return err } // skip checking if symlinks point to non-existing files, such symlinks can be useful // also skip named pipes, because they hanging on open if f.Mode()&(os.ModeSymlink|os.ModeNamedPipe) != 0 { return nil } if !f.IsDir() { currentFile, err := os.Open(filePath) if err != nil && os.IsPermission(err) { return fmt.Errorf("no permission to read from '%s'", filePath) } currentFile.Close() } return nil }) } func StringsContainsNoCase(slice []string, s string) bool { for _, ss := range slice { if strings.ToLower(s) == strings.ToLower(ss) { return true } } return false }