func (h *Handler) handleInternalRedirect(rw http.ResponseWriter, req *http.Request, path string) {
url, err := req.URL.Parse(path)
if err != nil {
rw.WriteHeader(http.StatusInternalServerError)
h.printf("cgi: error resolving local URI path %q: %v", path, err)
return
}
// TODO: RFC 3875 isn't clear if only GET is supported, but it
// suggests so: "Note that any message-body attached to the
// request (such as for a POST request) may not be available
// to the resource that is the target of the redirect." We
// should do some tests against Apache to see how it handles
// POST, HEAD, etc. Does the internal redirect get the same
// method or just GET? What about incoming headers?
// (e.g. Cookies) Which headers, if any, are copied into the
// second request?
newReq := &http.Request{
Method: "GET",
URL: url,
Proto: "HTTP/1.1",
ProtoMajor: 1,
ProtoMinor: 1,
Header: make(http.Header),
Host: url.Host,
RemoteAddr: req.RemoteAddr,
TLS: req.TLS,
}
h.PathLocationHandler.ServeHTTP(rw, newReq)
}
func (p *ReverseProxy) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
transport := p.Transport
if transport == nil {
transport = http.DefaultTransport
}
outreq := new(http.Request)
*outreq = *req // includes shallow copies of maps, but okay
p.Director(outreq)
outreq.Proto = "HTTP/1.1"
outreq.ProtoMajor = 1
outreq.ProtoMinor = 1
outreq.Close = false
// Remove hop-by-hop headers to the backend. Especially
// important is "Connection" because we want a persistent
// connection, regardless of what the client sent to us. This
// is modifying the same underlying map from req (shallow
// copied above) so we only copy it if necessary.
copiedHeaders := false
for _, h := range hopHeaders {
if outreq.Header.Get(h) != "" {
if !copiedHeaders {
outreq.Header = make(http.Header)
copyHeader(outreq.Header, req.Header)
copiedHeaders = true
}
outreq.Header.Del(h)
}
}
if clientIP, _, err := net.SplitHostPort(req.RemoteAddr); err == nil {
// If we aren't the first proxy retain prior
// X-Forwarded-For information as a comma+space
// separated list and fold multiple headers into one.
if prior, ok := outreq.Header["X-Forwarded-For"]; ok {
clientIP = strings.Join(prior, ", ") + ", " + clientIP
}
outreq.Header.Set("X-Forwarded-For", clientIP)
}
res, err := transport.RoundTrip(outreq)
if err != nil {
p.logf("http: proxy error: %v", err)
rw.WriteHeader(http.StatusInternalServerError)
return
}
defer res.Body.Close()
for _, h := range hopHeaders {
res.Header.Del(h)
}
copyHeader(rw.Header(), res.Header)
rw.WriteHeader(res.StatusCode)
p.copyResponse(rw, res.Body)
}
func (name handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "text/plain; charset=utf-8")
debug, _ := strconv.Atoi(r.FormValue("debug"))
p := pprof.Lookup(string(name))
if p == nil {
w.WriteHeader(404)
fmt.Fprintf(w, "Unknown profile: %s\n", name)
return
}
gc, _ := strconv.Atoi(r.FormValue("gc"))
if name == "heap" && gc > 0 {
runtime.GC()
}
p.WriteTo(w, debug)
return
}
// Profile responds with the pprof-formatted cpu profile.
// The package initialization registers it as /debug/pprof/profile.
func Profile(w http.ResponseWriter, r *http.Request) {
sec, _ := strconv.ParseInt(r.FormValue("seconds"), 10, 64)
if sec == 0 {
sec = 30
}
// Set Content Type assuming StartCPUProfile will work,
// because if it does it starts writing.
w.Header().Set("Content-Type", "application/octet-stream")
if err := pprof.StartCPUProfile(w); err != nil {
// StartCPUProfile failed, so no writes yet.
// Can change header back to text content
// and send error code.
w.Header().Set("Content-Type", "text/plain; charset=utf-8")
w.WriteHeader(http.StatusInternalServerError)
fmt.Fprintf(w, "Could not enable CPU profiling: %s\n", err)
return
}
time.Sleep(time.Duration(sec) * time.Second)
pprof.StopCPUProfile()
}
func (h *Handler) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
root := h.Root
if root == "" {
root = "/"
}
if len(req.TransferEncoding) > 0 && req.TransferEncoding[0] == "chunked" {
rw.WriteHeader(http.StatusBadRequest)
rw.Write([]byte("Chunked request bodies are not supported by CGI."))
return
}
pathInfo := req.URL.Path
if root != "/" && strings.HasPrefix(pathInfo, root) {
pathInfo = pathInfo[len(root):]
}
port := "80"
if matches := trailingPort.FindStringSubmatch(req.Host); len(matches) != 0 {
port = matches[1]
}
env := []string{
"SERVER_SOFTWARE=go",
"SERVER_NAME=" + req.Host,
"SERVER_PROTOCOL=HTTP/1.1",
"HTTP_HOST=" + req.Host,
"GATEWAY_INTERFACE=CGI/1.1",
"REQUEST_METHOD=" + req.Method,
"QUERY_STRING=" + req.URL.RawQuery,
"REQUEST_URI=" + req.URL.RequestURI(),
"PATH_INFO=" + pathInfo,
"SCRIPT_NAME=" + root,
"SCRIPT_FILENAME=" + h.Path,
"REMOTE_ADDR=" + req.RemoteAddr,
"REMOTE_HOST=" + req.RemoteAddr,
"SERVER_PORT=" + port,
}
if req.TLS != nil {
env = append(env, "HTTPS=on")
}
for k, v := range req.Header {
k = strings.Map(upperCaseAndUnderscore, k)
joinStr := ", "
if k == "COOKIE" {
joinStr = "; "
}
env = append(env, "HTTP_"+k+"="+strings.Join(v, joinStr))
}
if req.ContentLength > 0 {
env = append(env, fmt.Sprintf("CONTENT_LENGTH=%d", req.ContentLength))
}
if ctype := req.Header.Get("Content-Type"); ctype != "" {
env = append(env, "CONTENT_TYPE="+ctype)
}
if h.Env != nil {
env = append(env, h.Env...)
}
envPath := os.Getenv("PATH")
if envPath == "" {
envPath = "/bin:/usr/bin:/usr/ucb:/usr/bsd:/usr/local/bin"
}
env = append(env, "PATH="+envPath)
for _, e := range h.InheritEnv {
if v := os.Getenv(e); v != "" {
env = append(env, e+"="+v)
}
}
for _, e := range osDefaultInheritEnv[runtime.GOOS] {
if v := os.Getenv(e); v != "" {
env = append(env, e+"="+v)
}
}
env = removeLeadingDuplicates(env)
var cwd, path string
if h.Dir != "" {
path = h.Path
cwd = h.Dir
} else {
cwd, path = filepath.Split(h.Path)
}
if cwd == "" {
cwd = "."
}
internalError := func(err error) {
rw.WriteHeader(http.StatusInternalServerError)
h.printf("CGI error: %v", err)
}
cmd := &exec.Cmd{
Path: path,
Args: append([]string{h.Path}, h.Args...),
Dir: cwd,
Env: env,
Stderr: os.Stderr, // for now
}
if req.ContentLength != 0 {
cmd.Stdin = req.Body
}
stdoutRead, err := cmd.StdoutPipe()
if err != nil {
internalError(err)
return
}
err = cmd.Start()
if err != nil {
internalError(err)
return
}
if hook := testHookStartProcess; hook != nil {
hook(cmd.Process)
}
defer cmd.Wait()
defer stdoutRead.Close()
linebody := bufio.NewReaderSize(stdoutRead, 1024)
headers := make(http.Header)
statusCode := 0
headerLines := 0
sawBlankLine := false
for {
line, isPrefix, err := linebody.ReadLine()
if isPrefix {
rw.WriteHeader(http.StatusInternalServerError)
h.printf("cgi: long header line from subprocess.")
return
}
if err == io.EOF {
break
}
if err != nil {
rw.WriteHeader(http.StatusInternalServerError)
h.printf("cgi: error reading headers: %v", err)
return
}
if len(line) == 0 {
sawBlankLine = true
break
}
headerLines++
parts := strings.SplitN(string(line), ":", 2)
if len(parts) < 2 {
h.printf("cgi: bogus header line: %s", string(line))
continue
}
header, val := parts[0], parts[1]
header = strings.TrimSpace(header)
val = strings.TrimSpace(val)
switch {
case header == "Status":
if len(val) < 3 {
h.printf("cgi: bogus status (short): %q", val)
return
}
code, err := strconv.Atoi(val[0:3])
if err != nil {
h.printf("cgi: bogus status: %q", val)
h.printf("cgi: line was %q", line)
return
}
statusCode = code
default:
headers.Add(header, val)
}
}
if headerLines == 0 || !sawBlankLine {
rw.WriteHeader(http.StatusInternalServerError)
h.printf("cgi: no headers")
return
}
if loc := headers.Get("Location"); loc != "" {
if strings.HasPrefix(loc, "/") && h.PathLocationHandler != nil {
h.handleInternalRedirect(rw, req, loc)
return
}
if statusCode == 0 {
statusCode = http.StatusFound
}
}
if statusCode == 0 && headers.Get("Content-Type") == "" {
rw.WriteHeader(http.StatusInternalServerError)
h.printf("cgi: missing required Content-Type in headers")
return
}
if statusCode == 0 {
statusCode = http.StatusOK
}
// Copy headers to rw's headers, after we've decided not to
// go into handleInternalRedirect, which won't want its rw
// headers to have been touched.
for k, vv := range headers {
for _, v := range vv {
rw.Header().Add(k, v)
}
}
rw.WriteHeader(statusCode)
_, err = io.Copy(rw, linebody)
if err != nil {
h.printf("cgi: copy error: %v", err)
// And kill the child CGI process so we don't hang on
// the deferred cmd.Wait above if the error was just
// the client (rw) going away. If it was a read error
// (because the child died itself), then the extra
// kill of an already-dead process is harmless (the PID
// won't be reused until the Wait above).
cmd.Process.Kill()
}
}