diff options
Diffstat (limited to 'src/vendor/golang.org/x/net/internal/httpcommon/request.go')
| -rw-r--r-- | src/vendor/golang.org/x/net/internal/httpcommon/request.go | 467 |
1 files changed, 467 insertions, 0 deletions
diff --git a/src/vendor/golang.org/x/net/internal/httpcommon/request.go b/src/vendor/golang.org/x/net/internal/httpcommon/request.go new file mode 100644 index 0000000000..1e10f89ebf --- /dev/null +++ b/src/vendor/golang.org/x/net/internal/httpcommon/request.go @@ -0,0 +1,467 @@ +// Copyright 2025 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. + +package httpcommon + +import ( + "context" + "errors" + "fmt" + "net/http/httptrace" + "net/textproto" + "net/url" + "sort" + "strconv" + "strings" + + "golang.org/x/net/http/httpguts" + "golang.org/x/net/http2/hpack" +) + +var ( + ErrRequestHeaderListSize = errors.New("request header list larger than peer's advertised limit") +) + +// Request is a subset of http.Request. +// It'd be simpler to pass an *http.Request, of course, but we can't depend on net/http +// without creating a dependency cycle. +type Request struct { + URL *url.URL + Method string + Host string + Header map[string][]string + Trailer map[string][]string + ActualContentLength int64 // 0 means 0, -1 means unknown +} + +// EncodeHeadersParam is parameters to EncodeHeaders. +type EncodeHeadersParam struct { + Request Request + + // AddGzipHeader indicates that an "accept-encoding: gzip" header should be + // added to the request. + AddGzipHeader bool + + // PeerMaxHeaderListSize, when non-zero, is the peer's MAX_HEADER_LIST_SIZE setting. + PeerMaxHeaderListSize uint64 + + // DefaultUserAgent is the User-Agent header to send when the request + // neither contains a User-Agent nor disables it. + DefaultUserAgent string +} + +// EncodeHeadersResult is the result of EncodeHeaders. +type EncodeHeadersResult struct { + HasBody bool + HasTrailers bool +} + +// EncodeHeaders constructs request headers common to HTTP/2 and HTTP/3. +// It validates a request and calls headerf with each pseudo-header and header +// for the request. +// The headerf function is called with the validated, canonicalized header name. +func EncodeHeaders(ctx context.Context, param EncodeHeadersParam, headerf func(name, value string)) (res EncodeHeadersResult, _ error) { + req := param.Request + + // Check for invalid connection-level headers. + if err := checkConnHeaders(req.Header); err != nil { + return res, err + } + + if req.URL == nil { + return res, errors.New("Request.URL is nil") + } + + host := req.Host + if host == "" { + host = req.URL.Host + } + host, err := httpguts.PunycodeHostPort(host) + if err != nil { + return res, err + } + if !httpguts.ValidHostHeader(host) { + return res, errors.New("invalid Host header") + } + + // isNormalConnect is true if this is a non-extended CONNECT request. + isNormalConnect := false + var protocol string + if vv := req.Header[":protocol"]; len(vv) > 0 { + protocol = vv[0] + } + if req.Method == "CONNECT" && protocol == "" { + isNormalConnect = true + } else if protocol != "" && req.Method != "CONNECT" { + return res, errors.New("invalid :protocol header in non-CONNECT request") + } + + // Validate the path, except for non-extended CONNECT requests which have no path. + var path string + if !isNormalConnect { + path = req.URL.RequestURI() + if !validPseudoPath(path) { + orig := path + path = strings.TrimPrefix(path, req.URL.Scheme+"://"+host) + if !validPseudoPath(path) { + if req.URL.Opaque != "" { + return res, fmt.Errorf("invalid request :path %q from URL.Opaque = %q", orig, req.URL.Opaque) + } else { + return res, fmt.Errorf("invalid request :path %q", orig) + } + } + } + } + + // Check for any invalid headers+trailers and return an error before we + // potentially pollute our hpack state. (We want to be able to + // continue to reuse the hpack encoder for future requests) + if err := validateHeaders(req.Header); err != "" { + return res, fmt.Errorf("invalid HTTP header %s", err) + } + if err := validateHeaders(req.Trailer); err != "" { + return res, fmt.Errorf("invalid HTTP trailer %s", err) + } + + trailers, err := commaSeparatedTrailers(req.Trailer) + if err != nil { + return res, err + } + + enumerateHeaders := func(f func(name, value string)) { + // 8.1.2.3 Request Pseudo-Header Fields + // The :path pseudo-header field includes the path and query parts of the + // target URI (the path-absolute production and optionally a '?' character + // followed by the query production, see Sections 3.3 and 3.4 of + // [RFC3986]). + f(":authority", host) + m := req.Method + if m == "" { + m = "GET" + } + f(":method", m) + if !isNormalConnect { + f(":path", path) + f(":scheme", req.URL.Scheme) + } + if protocol != "" { + f(":protocol", protocol) + } + if trailers != "" { + f("trailer", trailers) + } + + var didUA bool + for k, vv := range req.Header { + if asciiEqualFold(k, "host") || asciiEqualFold(k, "content-length") { + // Host is :authority, already sent. + // Content-Length is automatic, set below. + continue + } else if asciiEqualFold(k, "connection") || + asciiEqualFold(k, "proxy-connection") || + asciiEqualFold(k, "transfer-encoding") || + asciiEqualFold(k, "upgrade") || + asciiEqualFold(k, "keep-alive") { + // Per 8.1.2.2 Connection-Specific Header + // Fields, don't send connection-specific + // fields. We have already checked if any + // are error-worthy so just ignore the rest. + continue + } else if asciiEqualFold(k, "user-agent") { + // Match Go's http1 behavior: at most one + // User-Agent. If set to nil or empty string, + // then omit it. Otherwise if not mentioned, + // include the default (below). + didUA = true + if len(vv) < 1 { + continue + } + vv = vv[:1] + if vv[0] == "" { + continue + } + } else if asciiEqualFold(k, "cookie") { + // Per 8.1.2.5 To allow for better compression efficiency, the + // Cookie header field MAY be split into separate header fields, + // each with one or more cookie-pairs. + for _, v := range vv { + for { + p := strings.IndexByte(v, ';') + if p < 0 { + break + } + f("cookie", v[:p]) + p++ + // strip space after semicolon if any. + for p+1 <= len(v) && v[p] == ' ' { + p++ + } + v = v[p:] + } + if len(v) > 0 { + f("cookie", v) + } + } + continue + } else if k == ":protocol" { + // :protocol pseudo-header was already sent above. + continue + } + + for _, v := range vv { + f(k, v) + } + } + if shouldSendReqContentLength(req.Method, req.ActualContentLength) { + f("content-length", strconv.FormatInt(req.ActualContentLength, 10)) + } + if param.AddGzipHeader { + f("accept-encoding", "gzip") + } + if !didUA { + f("user-agent", param.DefaultUserAgent) + } + } + + // Do a first pass over the headers counting bytes to ensure + // we don't exceed cc.peerMaxHeaderListSize. This is done as a + // separate pass before encoding the headers to prevent + // modifying the hpack state. + if param.PeerMaxHeaderListSize > 0 { + hlSize := uint64(0) + enumerateHeaders(func(name, value string) { + hf := hpack.HeaderField{Name: name, Value: value} + hlSize += uint64(hf.Size()) + }) + + if hlSize > param.PeerMaxHeaderListSize { + return res, ErrRequestHeaderListSize + } + } + + trace := httptrace.ContextClientTrace(ctx) + + // Header list size is ok. Write the headers. + enumerateHeaders(func(name, value string) { + name, ascii := LowerHeader(name) + if !ascii { + // Skip writing invalid headers. Per RFC 7540, Section 8.1.2, header + // field names have to be ASCII characters (just as in HTTP/1.x). + return + } + + headerf(name, value) + + if trace != nil && trace.WroteHeaderField != nil { + trace.WroteHeaderField(name, []string{value}) + } + }) + + res.HasBody = req.ActualContentLength != 0 + res.HasTrailers = trailers != "" + return res, nil +} + +// IsRequestGzip reports whether we should add an Accept-Encoding: gzip header +// for a request. +func IsRequestGzip(method string, header map[string][]string, disableCompression bool) bool { + // TODO(bradfitz): this is a copy of the logic in net/http. Unify somewhere? + if !disableCompression && + len(header["Accept-Encoding"]) == 0 && + len(header["Range"]) == 0 && + method != "HEAD" { + // Request gzip only, not deflate. Deflate is ambiguous and + // not as universally supported anyway. + // See: https://zlib.net/zlib_faq.html#faq39 + // + // Note that we don't request this for HEAD requests, + // due to a bug in nginx: + // http://trac.nginx.org/nginx/ticket/358 + // https://golang.org/issue/5522 + // + // We don't request gzip if the request is for a range, since + // auto-decoding a portion of a gzipped document will just fail + // anyway. See https://golang.org/issue/8923 + return true + } + return false +} + +// checkConnHeaders checks whether req has any invalid connection-level headers. +// +// https://www.rfc-editor.org/rfc/rfc9114.html#section-4.2-3 +// https://www.rfc-editor.org/rfc/rfc9113.html#section-8.2.2-1 +// +// Certain headers are special-cased as okay but not transmitted later. +// For example, we allow "Transfer-Encoding: chunked", but drop the header when encoding. +func checkConnHeaders(h map[string][]string) error { + if vv := h["Upgrade"]; len(vv) > 0 && (vv[0] != "" && vv[0] != "chunked") { + return fmt.Errorf("invalid Upgrade request header: %q", vv) + } + if vv := h["Transfer-Encoding"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && vv[0] != "chunked") { + return fmt.Errorf("invalid Transfer-Encoding request header: %q", vv) + } + if vv := h["Connection"]; len(vv) > 0 && (len(vv) > 1 || vv[0] != "" && !asciiEqualFold(vv[0], "close") && !asciiEqualFold(vv[0], "keep-alive")) { + return fmt.Errorf("invalid Connection request header: %q", vv) + } + return nil +} + +func commaSeparatedTrailers(trailer map[string][]string) (string, error) { + keys := make([]string, 0, len(trailer)) + for k := range trailer { + k = CanonicalHeader(k) + switch k { + case "Transfer-Encoding", "Trailer", "Content-Length": + return "", fmt.Errorf("invalid Trailer key %q", k) + } + keys = append(keys, k) + } + if len(keys) > 0 { + sort.Strings(keys) + return strings.Join(keys, ","), nil + } + return "", nil +} + +// validPseudoPath reports whether v is a valid :path pseudo-header +// value. It must be either: +// +// - a non-empty string starting with '/' +// - the string '*', for OPTIONS requests. +// +// For now this is only used a quick check for deciding when to clean +// up Opaque URLs before sending requests from the Transport. +// See golang.org/issue/16847 +// +// We used to enforce that the path also didn't start with "//", but +// Google's GFE accepts such paths and Chrome sends them, so ignore +// that part of the spec. See golang.org/issue/19103. +func validPseudoPath(v string) bool { + return (len(v) > 0 && v[0] == '/') || v == "*" +} + +func validateHeaders(hdrs map[string][]string) string { + for k, vv := range hdrs { + if !httpguts.ValidHeaderFieldName(k) && k != ":protocol" { + return fmt.Sprintf("name %q", k) + } + for _, v := range vv { + if !httpguts.ValidHeaderFieldValue(v) { + // Don't include the value in the error, + // because it may be sensitive. + return fmt.Sprintf("value for header %q", k) + } + } + } + return "" +} + +// shouldSendReqContentLength reports whether we should send +// a "content-length" request header. This logic is basically a copy of the net/http +// transferWriter.shouldSendContentLength. +// The contentLength is the corrected contentLength (so 0 means actually 0, not unknown). +// -1 means unknown. +func shouldSendReqContentLength(method string, contentLength int64) bool { + if contentLength > 0 { + return true + } + if contentLength < 0 { + return false + } + // For zero bodies, whether we send a content-length depends on the method. + // It also kinda doesn't matter for http2 either way, with END_STREAM. + switch method { + case "POST", "PUT", "PATCH": + return true + default: + return false + } +} + +// ServerRequestParam is parameters to NewServerRequest. +type ServerRequestParam struct { + Method string + Scheme, Authority, Path string + Protocol string + Header map[string][]string +} + +// ServerRequestResult is the result of NewServerRequest. +type ServerRequestResult struct { + // Various http.Request fields. + URL *url.URL + RequestURI string + Trailer map[string][]string + + NeedsContinue bool // client provided an "Expect: 100-continue" header + + // If the request should be rejected, this is a short string suitable for passing + // to the http2 package's CountError function. + // It might be a bit odd to return errors this way rather than returning an error, + // but this ensures we don't forget to include a CountError reason. + InvalidReason string +} + +func NewServerRequest(rp ServerRequestParam) ServerRequestResult { + needsContinue := httpguts.HeaderValuesContainsToken(rp.Header["Expect"], "100-continue") + if needsContinue { + delete(rp.Header, "Expect") + } + // Merge Cookie headers into one "; "-delimited value. + if cookies := rp.Header["Cookie"]; len(cookies) > 1 { + rp.Header["Cookie"] = []string{strings.Join(cookies, "; ")} + } + + // Setup Trailers + var trailer map[string][]string + for _, v := range rp.Header["Trailer"] { + for _, key := range strings.Split(v, ",") { + key = textproto.CanonicalMIMEHeaderKey(textproto.TrimString(key)) + switch key { + case "Transfer-Encoding", "Trailer", "Content-Length": + // Bogus. (copy of http1 rules) + // Ignore. + default: + if trailer == nil { + trailer = make(map[string][]string) + } + trailer[key] = nil + } + } + } + delete(rp.Header, "Trailer") + + // "':authority' MUST NOT include the deprecated userinfo subcomponent + // for "http" or "https" schemed URIs." + // https://www.rfc-editor.org/rfc/rfc9113.html#section-8.3.1-2.3.8 + if strings.IndexByte(rp.Authority, '@') != -1 && (rp.Scheme == "http" || rp.Scheme == "https") { + return ServerRequestResult{ + InvalidReason: "userinfo_in_authority", + } + } + + var url_ *url.URL + var requestURI string + if rp.Method == "CONNECT" && rp.Protocol == "" { + url_ = &url.URL{Host: rp.Authority} + requestURI = rp.Authority // mimic HTTP/1 server behavior + } else { + var err error + url_, err = url.ParseRequestURI(rp.Path) + if err != nil { + return ServerRequestResult{ + InvalidReason: "bad_path", + } + } + requestURI = rp.Path + } + + return ServerRequestResult{ + URL: url_, + NeedsContinue: needsContinue, + RequestURI: requestURI, + Trailer: trailer, + } +} |