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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 13:14:23 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-28 13:14:23 +0000 |
commit | 73df946d56c74384511a194dd01dbe099584fd1a (patch) | |
tree | fd0bcea490dd81327ddfbb31e215439672c9a068 /src/net/http/cgi/child.go | |
parent | Initial commit. (diff) | |
download | golang-1.16-upstream.tar.xz golang-1.16-upstream.zip |
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/net/http/cgi/child.go')
-rw-r--r-- | src/net/http/cgi/child.go | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/src/net/http/cgi/child.go b/src/net/http/cgi/child.go new file mode 100644 index 0000000..0114da3 --- /dev/null +++ b/src/net/http/cgi/child.go @@ -0,0 +1,220 @@ +// Copyright 2011 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. + +// This file implements CGI from the perspective of a child +// process. + +package cgi + +import ( + "bufio" + "crypto/tls" + "errors" + "fmt" + "io" + "net" + "net/http" + "net/url" + "os" + "strconv" + "strings" +) + +// Request returns the HTTP request as represented in the current +// environment. This assumes the current program is being run +// by a web server in a CGI environment. +// The returned Request's Body is populated, if applicable. +func Request() (*http.Request, error) { + r, err := RequestFromMap(envMap(os.Environ())) + if err != nil { + return nil, err + } + if r.ContentLength > 0 { + r.Body = io.NopCloser(io.LimitReader(os.Stdin, r.ContentLength)) + } + return r, nil +} + +func envMap(env []string) map[string]string { + m := make(map[string]string) + for _, kv := range env { + if idx := strings.Index(kv, "="); idx != -1 { + m[kv[:idx]] = kv[idx+1:] + } + } + return m +} + +// RequestFromMap creates an http.Request from CGI variables. +// The returned Request's Body field is not populated. +func RequestFromMap(params map[string]string) (*http.Request, error) { + r := new(http.Request) + r.Method = params["REQUEST_METHOD"] + if r.Method == "" { + return nil, errors.New("cgi: no REQUEST_METHOD in environment") + } + + r.Proto = params["SERVER_PROTOCOL"] + var ok bool + r.ProtoMajor, r.ProtoMinor, ok = http.ParseHTTPVersion(r.Proto) + if !ok { + return nil, errors.New("cgi: invalid SERVER_PROTOCOL version") + } + + r.Close = true + r.Trailer = http.Header{} + r.Header = http.Header{} + + r.Host = params["HTTP_HOST"] + + if lenstr := params["CONTENT_LENGTH"]; lenstr != "" { + clen, err := strconv.ParseInt(lenstr, 10, 64) + if err != nil { + return nil, errors.New("cgi: bad CONTENT_LENGTH in environment: " + lenstr) + } + r.ContentLength = clen + } + + if ct := params["CONTENT_TYPE"]; ct != "" { + r.Header.Set("Content-Type", ct) + } + + // Copy "HTTP_FOO_BAR" variables to "Foo-Bar" Headers + for k, v := range params { + if !strings.HasPrefix(k, "HTTP_") || k == "HTTP_HOST" { + continue + } + r.Header.Add(strings.ReplaceAll(k[5:], "_", "-"), v) + } + + uriStr := params["REQUEST_URI"] + if uriStr == "" { + // Fallback to SCRIPT_NAME, PATH_INFO and QUERY_STRING. + uriStr = params["SCRIPT_NAME"] + params["PATH_INFO"] + s := params["QUERY_STRING"] + if s != "" { + uriStr += "?" + s + } + } + + // There's apparently a de-facto standard for this. + // https://web.archive.org/web/20170105004655/http://docstore.mik.ua/orelly/linux/cgi/ch03_02.htm#ch03-35636 + if s := params["HTTPS"]; s == "on" || s == "ON" || s == "1" { + r.TLS = &tls.ConnectionState{HandshakeComplete: true} + } + + if r.Host != "" { + // Hostname is provided, so we can reasonably construct a URL. + rawurl := r.Host + uriStr + if r.TLS == nil { + rawurl = "http://" + rawurl + } else { + rawurl = "https://" + rawurl + } + url, err := url.Parse(rawurl) + if err != nil { + return nil, errors.New("cgi: failed to parse host and REQUEST_URI into a URL: " + rawurl) + } + r.URL = url + } + // Fallback logic if we don't have a Host header or the URL + // failed to parse + if r.URL == nil { + url, err := url.Parse(uriStr) + if err != nil { + return nil, errors.New("cgi: failed to parse REQUEST_URI into a URL: " + uriStr) + } + r.URL = url + } + + // Request.RemoteAddr has its port set by Go's standard http + // server, so we do here too. + remotePort, _ := strconv.Atoi(params["REMOTE_PORT"]) // zero if unset or invalid + r.RemoteAddr = net.JoinHostPort(params["REMOTE_ADDR"], strconv.Itoa(remotePort)) + + return r, nil +} + +// Serve executes the provided Handler on the currently active CGI +// request, if any. If there's no current CGI environment +// an error is returned. The provided handler may be nil to use +// http.DefaultServeMux. +func Serve(handler http.Handler) error { + req, err := Request() + if err != nil { + return err + } + if req.Body == nil { + req.Body = http.NoBody + } + if handler == nil { + handler = http.DefaultServeMux + } + rw := &response{ + req: req, + header: make(http.Header), + bufw: bufio.NewWriter(os.Stdout), + } + handler.ServeHTTP(rw, req) + rw.Write(nil) // make sure a response is sent + if err = rw.bufw.Flush(); err != nil { + return err + } + return nil +} + +type response struct { + req *http.Request + header http.Header + code int + wroteHeader bool + wroteCGIHeader bool + bufw *bufio.Writer +} + +func (r *response) Flush() { + r.bufw.Flush() +} + +func (r *response) Header() http.Header { + return r.header +} + +func (r *response) Write(p []byte) (n int, err error) { + if !r.wroteHeader { + r.WriteHeader(http.StatusOK) + } + if !r.wroteCGIHeader { + r.writeCGIHeader(p) + } + return r.bufw.Write(p) +} + +func (r *response) WriteHeader(code int) { + if r.wroteHeader { + // Note: explicitly using Stderr, as Stdout is our HTTP output. + fmt.Fprintf(os.Stderr, "CGI attempted to write header twice on request for %s", r.req.URL) + return + } + r.wroteHeader = true + r.code = code +} + +// writeCGIHeader finalizes the header sent to the client and writes it to the output. +// p is not written by writeHeader, but is the first chunk of the body +// that will be written. It is sniffed for a Content-Type if none is +// set explicitly. +func (r *response) writeCGIHeader(p []byte) { + if r.wroteCGIHeader { + return + } + r.wroteCGIHeader = true + fmt.Fprintf(r.bufw, "Status: %d %s\r\n", r.code, http.StatusText(r.code)) + if _, hasType := r.header["Content-Type"]; !hasType { + r.header.Set("Content-Type", http.DetectContentType(p)) + } + r.header.Write(r.bufw) + r.bufw.WriteString("\r\n") + r.bufw.Flush() +} |