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Diffstat (limited to 'libgo/go/net/http/request.go')
-rw-r--r-- | libgo/go/net/http/request.go | 817 |
1 files changed, 817 insertions, 0 deletions
diff --git a/libgo/go/net/http/request.go b/libgo/go/net/http/request.go new file mode 100644 index 00000000000..4410ca1d11c --- /dev/null +++ b/libgo/go/net/http/request.go @@ -0,0 +1,817 @@ +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// HTTP Request reading and parsing. + +package http + +import ( + "bufio" + "bytes" + "crypto/tls" + "encoding/base64" + "errors" + "fmt" + "io" + "io/ioutil" + "mime" + "mime/multipart" + "net/textproto" + "net/url" + "strconv" + "strings" +) + +const ( + maxLineLength = 4096 // assumed <= bufio.defaultBufSize + maxValueLength = 4096 + maxHeaderLines = 1024 + chunkSize = 4 << 10 // 4 KB chunks + defaultMaxMemory = 32 << 20 // 32 MB +) + +// ErrMissingFile is returned by FormFile when the provided file field name +// is either not present in the request or not a file field. +var ErrMissingFile = errors.New("http: no such file") + +// HTTP request parsing errors. +type ProtocolError struct { + ErrorString string +} + +func (err *ProtocolError) Error() string { return err.ErrorString } + +var ( + ErrLineTooLong = &ProtocolError{"header line too long"} + ErrHeaderTooLong = &ProtocolError{"header too long"} + ErrShortBody = &ProtocolError{"entity body too short"} + ErrNotSupported = &ProtocolError{"feature not supported"} + ErrUnexpectedTrailer = &ProtocolError{"trailer header without chunked transfer encoding"} + ErrMissingContentLength = &ProtocolError{"missing ContentLength in HEAD response"} + ErrNotMultipart = &ProtocolError{"request Content-Type isn't multipart/form-data"} + ErrMissingBoundary = &ProtocolError{"no multipart boundary param Content-Type"} +) + +type badStringError struct { + what string + str string +} + +func (e *badStringError) Error() string { return fmt.Sprintf("%s %q", e.what, e.str) } + +// Headers that Request.Write handles itself and should be skipped. +var reqWriteExcludeHeader = map[string]bool{ + "Host": true, // not in Header map anyway + "User-Agent": true, + "Content-Length": true, + "Transfer-Encoding": true, + "Trailer": true, +} + +// A Request represents an HTTP request received by a server +// or to be sent by a client. +type Request struct { + Method string // GET, POST, PUT, etc. + URL *url.URL + + // The protocol version for incoming requests. + // Outgoing requests always use HTTP/1.1. + Proto string // "HTTP/1.0" + ProtoMajor int // 1 + ProtoMinor int // 0 + + // A header maps request lines to their values. + // If the header says + // + // accept-encoding: gzip, deflate + // Accept-Language: en-us + // Connection: keep-alive + // + // then + // + // Header = map[string][]string{ + // "Accept-Encoding": {"gzip, deflate"}, + // "Accept-Language": {"en-us"}, + // "Connection": {"keep-alive"}, + // } + // + // HTTP defines that header names are case-insensitive. + // The request parser implements this by canonicalizing the + // name, making the first character and any characters + // following a hyphen uppercase and the rest lowercase. + Header Header + + // The message body. + Body io.ReadCloser + + // ContentLength records the length of the associated content. + // The value -1 indicates that the length is unknown. + // Values >= 0 indicate that the given number of bytes may + // be read from Body. + // For outgoing requests, a value of 0 means unknown if Body is not nil. + ContentLength int64 + + // TransferEncoding lists the transfer encodings from outermost to + // innermost. An empty list denotes the "identity" encoding. + // TransferEncoding can usually be ignored; chunked encoding is + // automatically added and removed as necessary when sending and + // receiving requests. + TransferEncoding []string + + // Close indicates whether to close the connection after + // replying to this request. + Close bool + + // The host on which the URL is sought. + // Per RFC 2616, this is either the value of the Host: header + // or the host name given in the URL itself. + Host string + + // Form contains the parsed form data, including both the URL + // field's query parameters and the POST or PUT form data. + // This field is only available after ParseForm is called. + // The HTTP client ignores Form and uses Body instead. + Form url.Values + + // MultipartForm is the parsed multipart form, including file uploads. + // This field is only available after ParseMultipartForm is called. + // The HTTP client ignores MultipartForm and uses Body instead. + MultipartForm *multipart.Form + + // Trailer maps trailer keys to values. Like for Header, if the + // response has multiple trailer lines with the same key, they will be + // concatenated, delimited by commas. + // For server requests, Trailer is only populated after Body has been + // closed or fully consumed. + // Trailer support is only partially complete. + Trailer Header + + // RemoteAddr allows HTTP servers and other software to record + // the network address that sent the request, usually for + // logging. This field is not filled in by ReadRequest and + // has no defined format. The HTTP server in this package + // sets RemoteAddr to an "IP:port" address before invoking a + // handler. + // This field is ignored by the HTTP client. + RemoteAddr string + + // TLS allows HTTP servers and other software to record + // information about the TLS connection on which the request + // was received. This field is not filled in by ReadRequest. + // The HTTP server in this package sets the field for + // TLS-enabled connections before invoking a handler; + // otherwise it leaves the field nil. + // This field is ignored by the HTTP client. + TLS *tls.ConnectionState +} + +// ProtoAtLeast returns whether the HTTP protocol used +// in the request is at least major.minor. +func (r *Request) ProtoAtLeast(major, minor int) bool { + return r.ProtoMajor > major || + r.ProtoMajor == major && r.ProtoMinor >= minor +} + +// UserAgent returns the client's User-Agent, if sent in the request. +func (r *Request) UserAgent() string { + return r.Header.Get("User-Agent") +} + +// Cookies parses and returns the HTTP cookies sent with the request. +func (r *Request) Cookies() []*Cookie { + return readCookies(r.Header, "") +} + +var ErrNoCookie = errors.New("http: named cookied not present") + +// Cookie returns the named cookie provided in the request or +// ErrNoCookie if not found. +func (r *Request) Cookie(name string) (*Cookie, error) { + for _, c := range readCookies(r.Header, name) { + return c, nil + } + return nil, ErrNoCookie +} + +// AddCookie adds a cookie to the request. Per RFC 6265 section 5.4, +// AddCookie does not attach more than one Cookie header field. That +// means all cookies, if any, are written into the same line, +// separated by semicolon. +func (r *Request) AddCookie(c *Cookie) { + s := fmt.Sprintf("%s=%s", sanitizeName(c.Name), sanitizeValue(c.Value)) + if c := r.Header.Get("Cookie"); c != "" { + r.Header.Set("Cookie", c+"; "+s) + } else { + r.Header.Set("Cookie", s) + } +} + +// Referer returns the referring URL, if sent in the request. +// +// Referer is misspelled as in the request itself, a mistake from the +// earliest days of HTTP. This value can also be fetched from the +// Header map as Header["Referer"]; the benefit of making it available +// as a method is that the compiler can diagnose programs that use the +// alternate (correct English) spelling req.Referrer() but cannot +// diagnose programs that use Header["Referrer"]. +func (r *Request) Referer() string { + return r.Header.Get("Referer") +} + +// multipartByReader is a sentinel value. +// Its presence in Request.MultipartForm indicates that parsing of the request +// body has been handed off to a MultipartReader instead of ParseMultipartFrom. +var multipartByReader = &multipart.Form{ + Value: make(map[string][]string), + File: make(map[string][]*multipart.FileHeader), +} + +// MultipartReader returns a MIME multipart reader if this is a +// multipart/form-data POST request, else returns nil and an error. +// Use this function instead of ParseMultipartForm to +// process the request body as a stream. +func (r *Request) MultipartReader() (*multipart.Reader, error) { + if r.MultipartForm == multipartByReader { + return nil, errors.New("http: MultipartReader called twice") + } + if r.MultipartForm != nil { + return nil, errors.New("http: multipart handled by ParseMultipartForm") + } + r.MultipartForm = multipartByReader + return r.multipartReader() +} + +func (r *Request) multipartReader() (*multipart.Reader, error) { + v := r.Header.Get("Content-Type") + if v == "" { + return nil, ErrNotMultipart + } + d, params, err := mime.ParseMediaType(v) + if err != nil || d != "multipart/form-data" { + return nil, ErrNotMultipart + } + boundary, ok := params["boundary"] + if !ok { + return nil, ErrMissingBoundary + } + return multipart.NewReader(r.Body, boundary), nil +} + +// Return value if nonempty, def otherwise. +func valueOrDefault(value, def string) string { + if value != "" { + return value + } + return def +} + +const defaultUserAgent = "Go http package" + +// Write writes an HTTP/1.1 request -- header and body -- in wire format. +// This method consults the following fields of req: +// Host +// URL +// Method (defaults to "GET") +// Header +// ContentLength +// TransferEncoding +// Body +// +// If Body is present, Content-Length is <= 0 and TransferEncoding +// hasn't been set to "identity", Write adds "Transfer-Encoding: +// chunked" to the header. Body is closed after it is sent. +func (req *Request) Write(w io.Writer) error { + return req.write(w, false, nil) +} + +// WriteProxy is like Write but writes the request in the form +// expected by an HTTP proxy. In particular, WriteProxy writes the +// initial Request-URI line of the request with an absolute URI, per +// section 5.1.2 of RFC 2616, including the scheme and host. In +// either case, WriteProxy also writes a Host header, using either +// req.Host or req.URL.Host. +func (req *Request) WriteProxy(w io.Writer) error { + return req.write(w, true, nil) +} + +// extraHeaders may be nil +func (req *Request) write(w io.Writer, usingProxy bool, extraHeaders Header) error { + host := req.Host + if host == "" { + if req.URL == nil { + return errors.New("http: Request.Write on Request with no Host or URL set") + } + host = req.URL.Host + } + + urlStr := req.URL.RawPath + if strings.HasPrefix(urlStr, "?") { + urlStr = "/" + urlStr // Issue 2344 + } + if urlStr == "" { + urlStr = valueOrDefault(req.URL.RawPath, valueOrDefault(req.URL.EncodedPath(), "/")) + if req.URL.RawQuery != "" { + urlStr += "?" + req.URL.RawQuery + } + if usingProxy { + if urlStr == "" || urlStr[0] != '/' { + urlStr = "/" + urlStr + } + urlStr = req.URL.Scheme + "://" + host + urlStr + } + } + // TODO(bradfitz): escape at least newlines in urlStr? + + bw := bufio.NewWriter(w) + fmt.Fprintf(bw, "%s %s HTTP/1.1\r\n", valueOrDefault(req.Method, "GET"), urlStr) + + // Header lines + fmt.Fprintf(bw, "Host: %s\r\n", host) + + // Use the defaultUserAgent unless the Header contains one, which + // may be blank to not send the header. + userAgent := defaultUserAgent + if req.Header != nil { + if ua := req.Header["User-Agent"]; len(ua) > 0 { + userAgent = ua[0] + } + } + if userAgent != "" { + fmt.Fprintf(bw, "User-Agent: %s\r\n", userAgent) + } + + // Process Body,ContentLength,Close,Trailer + tw, err := newTransferWriter(req) + if err != nil { + return err + } + err = tw.WriteHeader(bw) + if err != nil { + return err + } + + // TODO: split long values? (If so, should share code with Conn.Write) + err = req.Header.WriteSubset(bw, reqWriteExcludeHeader) + if err != nil { + return err + } + + if extraHeaders != nil { + err = extraHeaders.Write(bw) + if err != nil { + return err + } + } + + io.WriteString(bw, "\r\n") + + // Write body and trailer + err = tw.WriteBody(bw) + if err != nil { + return err + } + bw.Flush() + return nil +} + +// Read a line of bytes (up to \n) from b. +// Give up if the line exceeds maxLineLength. +// The returned bytes are a pointer into storage in +// the bufio, so they are only valid until the next bufio read. +func readLineBytes(b *bufio.Reader) (p []byte, err error) { + if p, err = b.ReadSlice('\n'); err != nil { + // We always know when EOF is coming. + // If the caller asked for a line, there should be a line. + if err == io.EOF { + err = io.ErrUnexpectedEOF + } else if err == bufio.ErrBufferFull { + err = ErrLineTooLong + } + return nil, err + } + if len(p) >= maxLineLength { + return nil, ErrLineTooLong + } + + // Chop off trailing white space. + var i int + for i = len(p); i > 0; i-- { + if c := p[i-1]; c != ' ' && c != '\r' && c != '\t' && c != '\n' { + break + } + } + return p[0:i], nil +} + +// readLineBytes, but convert the bytes into a string. +func readLine(b *bufio.Reader) (s string, err error) { + p, e := readLineBytes(b) + if e != nil { + return "", e + } + return string(p), nil +} + +// Convert decimal at s[i:len(s)] to integer, +// returning value, string position where the digits stopped, +// and whether there was a valid number (digits, not too big). +func atoi(s string, i int) (n, i1 int, ok bool) { + const Big = 1000000 + if i >= len(s) || s[i] < '0' || s[i] > '9' { + return 0, 0, false + } + n = 0 + for ; i < len(s) && '0' <= s[i] && s[i] <= '9'; i++ { + n = n*10 + int(s[i]-'0') + if n > Big { + return 0, 0, false + } + } + return n, i, true +} + +// ParseHTTPVersion parses a HTTP version string. +// "HTTP/1.0" returns (1, 0, true). +func ParseHTTPVersion(vers string) (major, minor int, ok bool) { + if len(vers) < 5 || vers[0:5] != "HTTP/" { + return 0, 0, false + } + major, i, ok := atoi(vers, 5) + if !ok || i >= len(vers) || vers[i] != '.' { + return 0, 0, false + } + minor, i, ok = atoi(vers, i+1) + if !ok || i != len(vers) { + return 0, 0, false + } + return major, minor, true +} + +type chunkedReader struct { + r *bufio.Reader + n uint64 // unread bytes in chunk + err error +} + +func (cr *chunkedReader) beginChunk() { + // chunk-size CRLF + var line string + line, cr.err = readLine(cr.r) + if cr.err != nil { + return + } + cr.n, cr.err = strconv.Btoui64(line, 16) + if cr.err != nil { + return + } + if cr.n == 0 { + cr.err = io.EOF + } +} + +func (cr *chunkedReader) Read(b []uint8) (n int, err error) { + if cr.err != nil { + return 0, cr.err + } + if cr.n == 0 { + cr.beginChunk() + if cr.err != nil { + return 0, cr.err + } + } + if uint64(len(b)) > cr.n { + b = b[0:cr.n] + } + n, cr.err = cr.r.Read(b) + cr.n -= uint64(n) + if cr.n == 0 && cr.err == nil { + // end of chunk (CRLF) + b := make([]byte, 2) + if _, cr.err = io.ReadFull(cr.r, b); cr.err == nil { + if b[0] != '\r' || b[1] != '\n' { + cr.err = errors.New("malformed chunked encoding") + } + } + } + return n, cr.err +} + +// NewRequest returns a new Request given a method, URL, and optional body. +func NewRequest(method, urlStr string, body io.Reader) (*Request, error) { + u, err := url.Parse(urlStr) + if err != nil { + return nil, err + } + rc, ok := body.(io.ReadCloser) + if !ok && body != nil { + rc = ioutil.NopCloser(body) + } + req := &Request{ + Method: method, + URL: u, + Proto: "HTTP/1.1", + ProtoMajor: 1, + ProtoMinor: 1, + Header: make(Header), + Body: rc, + Host: u.Host, + } + if body != nil { + switch v := body.(type) { + case *strings.Reader: + req.ContentLength = int64(v.Len()) + case *bytes.Buffer: + req.ContentLength = int64(v.Len()) + } + } + + return req, nil +} + +// SetBasicAuth sets the request's Authorization header to use HTTP +// Basic Authentication with the provided username and password. +// +// With HTTP Basic Authentication the provided username and password +// are not encrypted. +func (r *Request) SetBasicAuth(username, password string) { + s := username + ":" + password + r.Header.Set("Authorization", "Basic "+base64.StdEncoding.EncodeToString([]byte(s))) +} + +// ReadRequest reads and parses a request from b. +func ReadRequest(b *bufio.Reader) (req *Request, err error) { + + tp := textproto.NewReader(b) + req = new(Request) + + // First line: GET /index.html HTTP/1.0 + var s string + if s, err = tp.ReadLine(); err != nil { + if err == io.EOF { + err = io.ErrUnexpectedEOF + } + return nil, err + } + + var f []string + if f = strings.SplitN(s, " ", 3); len(f) < 3 { + return nil, &badStringError{"malformed HTTP request", s} + } + var rawurl string + req.Method, rawurl, req.Proto = f[0], f[1], f[2] + var ok bool + if req.ProtoMajor, req.ProtoMinor, ok = ParseHTTPVersion(req.Proto); !ok { + return nil, &badStringError{"malformed HTTP version", req.Proto} + } + + if req.URL, err = url.ParseRequest(rawurl); err != nil { + return nil, err + } + + // Subsequent lines: Key: value. + mimeHeader, err := tp.ReadMIMEHeader() + if err != nil { + return nil, err + } + req.Header = Header(mimeHeader) + + // RFC2616: Must treat + // GET /index.html HTTP/1.1 + // Host: www.google.com + // and + // GET http://www.google.com/index.html HTTP/1.1 + // Host: doesntmatter + // the same. In the second case, any Host line is ignored. + req.Host = req.URL.Host + if req.Host == "" { + req.Host = req.Header.Get("Host") + } + req.Header.Del("Host") + + fixPragmaCacheControl(req.Header) + + // TODO: Parse specific header values: + // Accept + // Accept-Encoding + // Accept-Language + // Authorization + // Cache-Control + // Connection + // Date + // Expect + // From + // If-Match + // If-Modified-Since + // If-None-Match + // If-Range + // If-Unmodified-Since + // Max-Forwards + // Proxy-Authorization + // Referer [sic] + // TE (transfer-codings) + // Trailer + // Transfer-Encoding + // Upgrade + // User-Agent + // Via + // Warning + + err = readTransfer(req, b) + if err != nil { + return nil, err + } + + return req, nil +} + +// MaxBytesReader is similar to io.LimitReader but is intended for +// limiting the size of incoming request bodies. In contrast to +// io.LimitReader, MaxBytesReader's result is a ReadCloser, returns a +// non-EOF error for a Read beyond the limit, and Closes the +// underlying reader when its Close method is called. +// +// MaxBytesReader prevents clients from accidentally or maliciously +// sending a large request and wasting server resources. +func MaxBytesReader(w ResponseWriter, r io.ReadCloser, n int64) io.ReadCloser { + return &maxBytesReader{w: w, r: r, n: n} +} + +type maxBytesReader struct { + w ResponseWriter + r io.ReadCloser // underlying reader + n int64 // max bytes remaining + stopped bool +} + +func (l *maxBytesReader) Read(p []byte) (n int, err error) { + if l.n <= 0 { + if !l.stopped { + l.stopped = true + if res, ok := l.w.(*response); ok { + res.requestTooLarge() + } + } + return 0, errors.New("http: request body too large") + } + if int64(len(p)) > l.n { + p = p[:l.n] + } + n, err = l.r.Read(p) + l.n -= int64(n) + return +} + +func (l *maxBytesReader) Close() error { + return l.r.Close() +} + +// ParseForm parses the raw query from the URL. +// +// For POST or PUT requests, it also parses the request body as a form. +// If the request Body's size has not already been limited by MaxBytesReader, +// the size is capped at 10MB. +// +// ParseMultipartForm calls ParseForm automatically. +// It is idempotent. +func (r *Request) ParseForm() (err error) { + if r.Form != nil { + return + } + if r.URL != nil { + r.Form, err = url.ParseQuery(r.URL.RawQuery) + } + if r.Method == "POST" || r.Method == "PUT" { + if r.Body == nil { + return errors.New("missing form body") + } + ct := r.Header.Get("Content-Type") + ct, _, err := mime.ParseMediaType(ct) + switch { + case ct == "application/x-www-form-urlencoded": + var reader io.Reader = r.Body + maxFormSize := int64(1<<63 - 1) + if _, ok := r.Body.(*maxBytesReader); !ok { + maxFormSize = int64(10 << 20) // 10 MB is a lot of text. + reader = io.LimitReader(r.Body, maxFormSize+1) + } + b, e := ioutil.ReadAll(reader) + if e != nil { + if err == nil { + err = e + } + break + } + if int64(len(b)) > maxFormSize { + return errors.New("http: POST too large") + } + var newValues url.Values + newValues, e = url.ParseQuery(string(b)) + if err == nil { + err = e + } + if r.Form == nil { + r.Form = make(url.Values) + } + // Copy values into r.Form. TODO: make this smoother. + for k, vs := range newValues { + for _, value := range vs { + r.Form.Add(k, value) + } + } + case ct == "multipart/form-data": + // handled by ParseMultipartForm (which is calling us, or should be) + // TODO(bradfitz): there are too many possible + // orders to call too many functions here. + // Clean this up and write more tests. + // request_test.go contains the start of this, + // in TestRequestMultipartCallOrder. + default: + return &badStringError{"unknown Content-Type", ct} + } + } + return err +} + +// ParseMultipartForm parses a request body as multipart/form-data. +// The whole request body is parsed and up to a total of maxMemory bytes of +// its file parts are stored in memory, with the remainder stored on +// disk in temporary files. +// ParseMultipartForm calls ParseForm if necessary. +// After one call to ParseMultipartForm, subsequent calls have no effect. +func (r *Request) ParseMultipartForm(maxMemory int64) error { + if r.MultipartForm == multipartByReader { + return errors.New("http: multipart handled by MultipartReader") + } + if r.Form == nil { + err := r.ParseForm() + if err != nil { + return err + } + } + if r.MultipartForm != nil { + return nil + } + + mr, err := r.multipartReader() + if err == ErrNotMultipart { + return nil + } else if err != nil { + return err + } + + f, err := mr.ReadForm(maxMemory) + if err != nil { + return err + } + for k, v := range f.Value { + r.Form[k] = append(r.Form[k], v...) + } + r.MultipartForm = f + + return nil +} + +// FormValue returns the first value for the named component of the query. +// FormValue calls ParseMultipartForm and ParseForm if necessary. +func (r *Request) FormValue(key string) string { + if r.Form == nil { + r.ParseMultipartForm(defaultMaxMemory) + } + if vs := r.Form[key]; len(vs) > 0 { + return vs[0] + } + return "" +} + +// FormFile returns the first file for the provided form key. +// FormFile calls ParseMultipartForm and ParseForm if necessary. +func (r *Request) FormFile(key string) (multipart.File, *multipart.FileHeader, error) { + if r.MultipartForm == multipartByReader { + return nil, nil, errors.New("http: multipart handled by MultipartReader") + } + if r.MultipartForm == nil { + err := r.ParseMultipartForm(defaultMaxMemory) + if err != nil { + return nil, nil, err + } + } + if r.MultipartForm != nil && r.MultipartForm.File != nil { + if fhs := r.MultipartForm.File[key]; len(fhs) > 0 { + f, err := fhs[0].Open() + return f, fhs[0], err + } + } + return nil, nil, ErrMissingFile +} + +func (r *Request) expectsContinue() bool { + return strings.ToLower(r.Header.Get("Expect")) == "100-continue" +} + +func (r *Request) wantsHttp10KeepAlive() bool { + if r.ProtoMajor != 1 || r.ProtoMinor != 0 { + return false + } + return strings.Contains(strings.ToLower(r.Header.Get("Connection")), "keep-alive") +} |