diff options
Diffstat (limited to 'modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go')
| -rw-r--r-- | modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go b/modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go new file mode 100644 index 0000000..91039c9 --- /dev/null +++ b/modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go @@ -0,0 +1,301 @@ +// Copyright 2015 Matthew Holt and The Caddy Authors +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package fastcgi + +import ( + "context" + "crypto/tls" + "fmt" + "net/http" + "net/url" + "path" + "path/filepath" + "strconv" + "strings" + "time" + + "github.com/caddyserver/caddy/v2/modules/caddyhttp" + "github.com/caddyserver/caddy/v2/modules/caddyhttp/reverseproxy" + "github.com/caddyserver/caddy/v2/modules/caddytls" + + "github.com/caddyserver/caddy/v2" +) + +func init() { + caddy.RegisterModule(Transport{}) +} + +// Transport facilitates FastCGI communication. +type Transport struct { + // TODO: Populate these + softwareName string + softwareVersion string + serverName string + serverPort string + + // Use this directory as the fastcgi root directory. Defaults to the root + // directory of the parent virtual host. + Root string `json:"root,omitempty"` + + // The path in the URL will be split into two, with the first piece ending + // with the value of SplitPath. The first piece will be assumed as the + // actual resource (CGI script) name, and the second piece will be set to + // PATH_INFO for the CGI script to use. + SplitPath string `json:"split_path,omitempty"` + + // Environment variables (TODO: make a map of string to value...?) + EnvVars [][2]string `json:"env,omitempty"` + + // The duration used to set a deadline when connecting to an upstream. + DialTimeout caddy.Duration `json:"dial_timeout,omitempty"` + + // The duration used to set a deadline when reading from the FastCGI server. + ReadTimeout caddy.Duration `json:"read_timeout,omitempty"` + + // The duration used to set a deadline when sending to the FastCGI server. + WriteTimeout caddy.Duration `json:"write_timeout,omitempty"` +} + +// CaddyModule returns the Caddy module information. +func (Transport) CaddyModule() caddy.ModuleInfo { + return caddy.ModuleInfo{ + Name: "http.handlers.reverse_proxy.transport.fastcgi", + New: func() caddy.Module { return new(Transport) }, + } +} + +// Provision sets up t. +func (t *Transport) Provision(_ caddy.Context) error { + if t.Root == "" { + t.Root = "{http.vars.root}" + } + return nil +} + +// RoundTrip implements http.RoundTripper. +func (t Transport) RoundTrip(r *http.Request) (*http.Response, error) { + env, err := t.buildEnv(r) + if err != nil { + return nil, fmt.Errorf("building environment: %v", err) + } + + // TODO: doesn't dialer have a Timeout field? + ctx := r.Context() + if t.DialTimeout > 0 { + var cancel context.CancelFunc + ctx, cancel = context.WithTimeout(ctx, time.Duration(t.DialTimeout)) + defer cancel() + } + + // extract dial information from request (this + // should embedded by the reverse proxy) + network, address := "tcp", r.URL.Host + if dialInfoVal := ctx.Value(reverseproxy.DialInfoCtxKey); dialInfoVal != nil { + dialInfo := dialInfoVal.(reverseproxy.DialInfo) + network = dialInfo.Network + address = dialInfo.Address + } + + fcgiBackend, err := DialContext(ctx, network, address) + if err != nil { + return nil, fmt.Errorf("dialing backend: %v", err) + } + // fcgiBackend gets closed when response body is closed (see clientCloser) + + // read/write timeouts + if err := fcgiBackend.SetReadTimeout(time.Duration(t.ReadTimeout)); err != nil { + return nil, fmt.Errorf("setting read timeout: %v", err) + } + if err := fcgiBackend.SetWriteTimeout(time.Duration(t.WriteTimeout)); err != nil { + return nil, fmt.Errorf("setting write timeout: %v", err) + } + + contentLength := r.ContentLength + if contentLength == 0 { + contentLength, _ = strconv.ParseInt(r.Header.Get("Content-Length"), 10, 64) + } + + var resp *http.Response + switch r.Method { + case http.MethodHead: + resp, err = fcgiBackend.Head(env) + case http.MethodGet: + resp, err = fcgiBackend.Get(env, r.Body, contentLength) + case http.MethodOptions: + resp, err = fcgiBackend.Options(env) + default: + resp, err = fcgiBackend.Post(env, r.Method, r.Header.Get("Content-Type"), r.Body, contentLength) + } + + return resp, err +} + +// buildEnv returns a set of CGI environment variables for the request. +func (t Transport) buildEnv(r *http.Request) (map[string]string, error) { + repl := r.Context().Value(caddy.ReplacerCtxKey).(caddy.Replacer) + + var env map[string]string + + // Separate remote IP and port; more lenient than net.SplitHostPort + var ip, port string + if idx := strings.LastIndex(r.RemoteAddr, ":"); idx > -1 { + ip = r.RemoteAddr[:idx] + port = r.RemoteAddr[idx+1:] + } else { + ip = r.RemoteAddr + } + + // Remove [] from IPv6 addresses + ip = strings.Replace(ip, "[", "", 1) + ip = strings.Replace(ip, "]", "", 1) + + root := repl.ReplaceAll(t.Root, ".") + fpath := r.URL.Path + + // Split path in preparation for env variables. + // Previous canSplit checks ensure this can never be -1. + // TODO: I haven't brought over canSplit; make sure this doesn't break + splitPos := t.splitPos(fpath) + + // Request has the extension; path was split successfully + docURI := fpath[:splitPos+len(t.SplitPath)] + pathInfo := fpath[splitPos+len(t.SplitPath):] + scriptName := fpath + + // Strip PATH_INFO from SCRIPT_NAME + scriptName = strings.TrimSuffix(scriptName, pathInfo) + + // SCRIPT_FILENAME is the absolute path of SCRIPT_NAME + scriptFilename := filepath.Join(root, scriptName) + + // Add vhost path prefix to scriptName. Otherwise, some PHP software will + // have difficulty discovering its URL. + pathPrefix, _ := r.Context().Value(caddy.CtxKey("path_prefix")).(string) + scriptName = path.Join(pathPrefix, scriptName) + + // Get the request URL from context. The context stores the original URL in case + // it was changed by a middleware such as rewrite. By default, we pass the + // original URI in as the value of REQUEST_URI (the user can overwrite this + // if desired). Most PHP apps seem to want the original URI. Besides, this is + // how nginx defaults: http://stackoverflow.com/a/12485156/1048862 + reqURL, ok := r.Context().Value(caddyhttp.OriginalURLCtxKey).(url.URL) + if !ok { + // some requests, like active health checks, don't add this to + // the request context, so we can just use the current URL + reqURL = *r.URL + } + + requestScheme := "http" + if r.TLS != nil { + requestScheme = "https" + } + + // Some variables are unused but cleared explicitly to prevent + // the parent environment from interfering. + env = map[string]string{ + // Variables defined in CGI 1.1 spec + "AUTH_TYPE": "", // Not used + "CONTENT_LENGTH": r.Header.Get("Content-Length"), + "CONTENT_TYPE": r.Header.Get("Content-Type"), + "GATEWAY_INTERFACE": "CGI/1.1", + "PATH_INFO": pathInfo, + "QUERY_STRING": r.URL.RawQuery, + "REMOTE_ADDR": ip, + "REMOTE_HOST": ip, // For speed, remote host lookups disabled + "REMOTE_PORT": port, + "REMOTE_IDENT": "", // Not used + "REMOTE_USER": "", // TODO: once there are authentication handlers, populate this + "REQUEST_METHOD": r.Method, + "REQUEST_SCHEME": requestScheme, + "SERVER_NAME": t.serverName, + "SERVER_PORT": t.serverPort, + "SERVER_PROTOCOL": r.Proto, + "SERVER_SOFTWARE": t.softwareName + "/" + t.softwareVersion, + + // Other variables + "DOCUMENT_ROOT": root, + "DOCUMENT_URI": docURI, + "HTTP_HOST": r.Host, // added here, since not always part of headers + "REQUEST_URI": reqURL.RequestURI(), + "SCRIPT_FILENAME": scriptFilename, + "SCRIPT_NAME": scriptName, + } + + // compliance with the CGI specification requires that + // PATH_TRANSLATED should only exist if PATH_INFO is defined. + // Info: https://www.ietf.org/rfc/rfc3875 Page 14 + if env["PATH_INFO"] != "" { + env["PATH_TRANSLATED"] = filepath.Join(root, pathInfo) // Info: http://www.oreilly.com/openbook/cgi/ch02_04.html + } + + // Some web apps rely on knowing HTTPS or not + if r.TLS != nil { + env["HTTPS"] = "on" + // and pass the protocol details in a manner compatible with apache's mod_ssl + // (which is why these have a SSL_ prefix and not TLS_). + v, ok := tlsProtocolStrings[r.TLS.Version] + if ok { + env["SSL_PROTOCOL"] = v + } + // and pass the cipher suite in a manner compatible with apache's mod_ssl + for k, v := range caddytls.SupportedCipherSuites { + if v == r.TLS.CipherSuite { + env["SSL_CIPHER"] = k + break + } + } + } + + // Add env variables from config (with support for placeholders in values) + for _, envVar := range t.EnvVars { + env[envVar[0]] = repl.ReplaceAll(envVar[1], "") + } + + // Add all HTTP headers to env variables + for field, val := range r.Header { + header := strings.ToUpper(field) + header = headerNameReplacer.Replace(header) + env["HTTP_"+header] = strings.Join(val, ", ") + } + return env, nil +} + +// splitPos returns the index where path should +// be split based on t.SplitPath. +func (t Transport) splitPos(path string) int { + // TODO: + // if httpserver.CaseSensitivePath { + // return strings.Index(path, r.SplitPath) + // } + return strings.Index(strings.ToLower(path), strings.ToLower(t.SplitPath)) +} + +// TODO: +// Map of supported protocols to Apache ssl_mod format +// Note that these are slightly different from SupportedProtocols in caddytls/config.go +var tlsProtocolStrings = map[uint16]string{ + tls.VersionTLS10: "TLSv1", + tls.VersionTLS11: "TLSv1.1", + tls.VersionTLS12: "TLSv1.2", + tls.VersionTLS13: "TLSv1.3", +} + +var headerNameReplacer = strings.NewReplacer(" ", "_", "-", "_") + +// Interface guards +var ( + _ caddy.Provisioner = (*Transport)(nil) + _ http.RoundTripper = (*Transport)(nil) +) |