caddy/modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go
Matthew Holt e43b6d8178 core: Variadic Context.Logger(); soft deprecation
Ideally I'd just remove the parameter to caddy.Context.Logger(), but
this would break most Caddy plugins.

Instead, I'm making it variadic and marking it as partially deprecated.
In the future, I might completely remove the parameter once most
plugins have updated.
2022-09-16 16:55:36 -06:00

434 lines
13 KiB
Go

// 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 (
"crypto/tls"
"fmt"
"net"
"net/http"
"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"
"go.uber.org/zap"
"go.uber.org/zap/zapcore"
"github.com/caddyserver/caddy/v2"
)
var noopLogger = zap.NewNop()
func init() {
caddy.RegisterModule(Transport{})
}
// Transport facilitates FastCGI communication.
type Transport struct {
// 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.
//
// Future enhancements should be careful to avoid CVE-2019-11043,
// which can be mitigated with use of a try_files-like behavior
// that 404s if the fastcgi path info is not found.
SplitPath []string `json:"split_path,omitempty"`
// Path declared as root directory will be resolved to its absolute value
// after the evaluation of any symbolic links.
// Due to the nature of PHP opcache, root directory path is cached: when
// using a symlinked directory as root this could generate errors when
// symlink is changed without php-fpm being restarted; enabling this
// directive will set $_SERVER['DOCUMENT_ROOT'] to the real directory path.
ResolveRootSymlink bool `json:"resolve_root_symlink,omitempty"`
// Extra environment variables.
EnvVars map[string]string `json:"env,omitempty"`
// The duration used to set a deadline when connecting to an upstream. Default: `3s`.
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"`
// Capture and log any messages sent by the upstream on stderr. Logs at WARN
// level by default. If the response has a 4xx or 5xx status ERROR level will
// be used instead.
CaptureStderr bool `json:"capture_stderr,omitempty"`
serverSoftware string
logger *zap.Logger
}
// CaddyModule returns the Caddy module information.
func (Transport) CaddyModule() caddy.ModuleInfo {
return caddy.ModuleInfo{
ID: "http.reverse_proxy.transport.fastcgi",
New: func() caddy.Module { return new(Transport) },
}
}
// Provision sets up t.
func (t *Transport) Provision(ctx caddy.Context) error {
t.logger = ctx.Logger()
if t.Root == "" {
t.Root = "{http.vars.root}"
}
version, _ := caddy.Version()
t.serverSoftware = "Caddy/" + version
// Set a relatively short default dial timeout.
// This is helpful to make load-balancer retries more speedy.
if t.DialTimeout == 0 {
t.DialTimeout = caddy.Duration(3 * time.Second)
}
return nil
}
// RoundTrip implements http.RoundTripper.
func (t Transport) RoundTrip(r *http.Request) (*http.Response, error) {
server := r.Context().Value(caddyhttp.ServerCtxKey).(*caddyhttp.Server)
// Disallow null bytes in the request path, because
// PHP upstreams may do bad things, like execute a
// non-PHP file as PHP code. See #4574
if strings.Contains(r.URL.Path, "\x00") {
return nil, caddyhttp.Error(http.StatusBadRequest, fmt.Errorf("invalid request path"))
}
env, err := t.buildEnv(r)
if err != nil {
return nil, fmt.Errorf("building environment: %v", err)
}
ctx := r.Context()
// extract dial information from request (should have been embedded by the reverse proxy)
network, address := "tcp", r.URL.Host
if dialInfo, ok := reverseproxy.GetDialInfo(ctx); ok {
network = dialInfo.Network
address = dialInfo.Address
}
logCreds := server.Logs != nil && server.Logs.ShouldLogCredentials
loggableReq := caddyhttp.LoggableHTTPRequest{
Request: r,
ShouldLogCredentials: logCreds,
}
loggableEnv := loggableEnv{vars: env, logCredentials: logCreds}
logger := t.logger.With(
zap.Object("request", loggableReq),
zap.Object("env", loggableEnv),
)
logger.Debug("roundtrip",
zap.String("dial", address),
zap.Object("env", loggableEnv),
zap.Object("request", loggableReq))
// connect to the backend
dialer := net.Dialer{Timeout: time.Duration(t.DialTimeout)}
conn, err := dialer.DialContext(ctx, network, address)
if err != nil {
return nil, fmt.Errorf("dialing backend: %v", err)
}
defer func() {
// conn will be closed with the response body unless there's an error
if err != nil {
conn.Close()
}
}()
// create the client that will facilitate the protocol
client := client{
rwc: conn,
reqID: 1,
logger: logger,
}
// read/write timeouts
if err = client.SetReadTimeout(time.Duration(t.ReadTimeout)); err != nil {
return nil, fmt.Errorf("setting read timeout: %v", err)
}
if err = client.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 = client.Head(env)
case http.MethodGet:
resp, err = client.Get(env, r.Body, contentLength)
case http.MethodOptions:
resp, err = client.Options(env)
default:
resp, err = client.Post(env, r.Method, r.Header.Get("Content-Type"), r.Body, contentLength)
}
if err != nil {
return nil, err
}
return resp, nil
}
// buildEnv returns a set of CGI environment variables for the request.
func (t Transport) buildEnv(r *http.Request) (envVars, error) {
repl := r.Context().Value(caddy.ReplacerCtxKey).(*caddy.Replacer)
var env envVars
// 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)
// make sure file root is absolute
root, err := filepath.Abs(repl.ReplaceAll(t.Root, "."))
if err != nil {
return nil, err
}
if t.ResolveRootSymlink {
root, err = filepath.EvalSymlinks(root)
if err != nil {
return nil, err
}
}
fpath := r.URL.Path
scriptName := fpath
docURI := fpath
// split "actual path" from "path info" if configured
var pathInfo string
if splitPos := t.splitPos(fpath); splitPos > -1 {
docURI = fpath[:splitPos]
pathInfo = fpath[splitPos:]
// Strip PATH_INFO from SCRIPT_NAME
scriptName = strings.TrimSuffix(scriptName, pathInfo)
}
// Try to grab the path remainder from a file matcher
// if we didn't get a split result here.
// See https://github.com/caddyserver/caddy/issues/3718
if pathInfo == "" {
if remainder, ok := repl.GetString("http.matchers.file.remainder"); ok {
pathInfo = remainder
}
}
// SCRIPT_FILENAME is the absolute path of SCRIPT_NAME
scriptFilename := caddyhttp.SanitizedPathJoin(root, scriptName)
// Ensure the SCRIPT_NAME has a leading slash for compliance with RFC3875
// Info: https://tools.ietf.org/html/rfc3875#section-4.1.13
if scriptName != "" && !strings.HasPrefix(scriptName, "/") {
scriptName = "/" + 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
origReq := r.Context().Value(caddyhttp.OriginalRequestCtxKey).(http.Request)
requestScheme := "http"
if r.TLS != nil {
requestScheme = "https"
}
reqHost, reqPort, err := net.SplitHostPort(r.Host)
if err != nil {
// whatever, just assume there was no port
reqHost = r.Host
}
authUser := ""
if val, ok := repl.Get("http.auth.user.id"); ok {
authUser = val.(string)
}
// Some variables are unused but cleared explicitly to prevent
// the parent environment from interfering.
env = envVars{
// 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": authUser,
"REQUEST_METHOD": r.Method,
"REQUEST_SCHEME": requestScheme,
"SERVER_NAME": reqHost,
"SERVER_PROTOCOL": r.Proto,
"SERVER_SOFTWARE": t.serverSoftware,
// Other variables
"DOCUMENT_ROOT": root,
"DOCUMENT_URI": docURI,
"HTTP_HOST": r.Host, // added here, since not always part of headers
"REQUEST_URI": origReq.URL.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"] = caddyhttp.SanitizedPathJoin(root, pathInfo) // Info: http://www.oreilly.com/openbook/cgi/ch02_04.html
}
// compliance with the CGI specification requires that
// the SERVER_PORT variable MUST be set to the TCP/IP port number on which this request is received from the client
// even if the port is the default port for the scheme and could otherwise be omitted from a URI.
// https://tools.ietf.org/html/rfc3875#section-4.1.15
if reqPort != "" {
env["SERVER_PORT"] = reqPort
} else if requestScheme == "http" {
env["SERVER_PORT"] = "80"
} else if requestScheme == "https" {
env["SERVER_PORT"] = "443"
}
// 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 _, cs := range caddytls.SupportedCipherSuites() {
if cs.ID == r.TLS.CipherSuite {
env["SSL_CIPHER"] = cs.Name
break
}
}
}
// Add env variables from config (with support for placeholders in values)
for key, value := range t.EnvVars {
env[key] = repl.ReplaceAll(value, "")
}
// 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: from v1...
// if httpserver.CaseSensitivePath {
// return strings.Index(path, r.SplitPath)
// }
if len(t.SplitPath) == 0 {
return 0
}
lowerPath := strings.ToLower(path)
for _, split := range t.SplitPath {
if idx := strings.Index(lowerPath, strings.ToLower(split)); idx > -1 {
return idx + len(split)
}
}
return -1
}
type envVars map[string]string
// loggableEnv is a simple type to allow for speeding up zap log encoding.
type loggableEnv struct {
vars envVars
logCredentials bool
}
func (env loggableEnv) MarshalLogObject(enc zapcore.ObjectEncoder) error {
for k, v := range env.vars {
if !env.logCredentials {
switch strings.ToLower(k) {
case "http_cookie", "http_set_cookie", "http_authorization", "http_proxy_authorization":
v = ""
}
}
enc.AddString(k, v)
}
return nil
}
// 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 (
_ zapcore.ObjectMarshaler = (*loggableEnv)(nil)
_ caddy.Provisioner = (*Transport)(nil)
_ http.RoundTripper = (*Transport)(nil)
)