org.apache.catalina.servlets.CGIServlet Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.catalina.servlets;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.Date;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.List;
import java.util.Locale;
import java.util.StringTokenizer;
import java.util.Vector;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.catalina.util.IOTools;
/**
* CGI-invoking servlet for web applications, used to execute scripts which
* comply to the Common Gateway Interface (CGI) specification and are named
* in the path-info used to invoke this servlet.
*
*
* Note: This code compiles and even works for simple CGI cases.
* Exhaustive testing has not been done. Please consider it beta
* quality. Feedback is appreciated to the author (see below).
*
*
*
* Example:
* If an instance of this servlet was mapped (using
* <web-app>/WEB-INF/web.xml) to:
*
*
*
* <web-app>/cgi-bin/*
*
*
*
* then the following request:
*
*
*
* http://localhost:8080/<web-app>/cgi-bin/dir1/script/pathinfo1
*
*
*
* would result in the execution of the script
*
*
*
* <web-app-root>/WEB-INF/cgi/dir1/script
*
*
*
* with the script's PATH_INFO set to /pathinfo1.
*
*
* Recommendation: House all your CGI scripts under
* <webapp>/WEB-INF/cgi. This will ensure that you do not
* accidentally expose your cgi scripts' code to the outside world and that
* your cgis will be cleanly ensconced underneath the WEB-INF (i.e.,
* non-content) area.
*
*
* The default CGI location is mentioned above. You have the flexibility to
* put CGIs wherever you want, however:
*
*
* The CGI search path will start at
* webAppRootDir + File.separator + cgiPathPrefix
* (or webAppRootDir alone if cgiPathPrefix is
* null).
*
*
* cgiPathPrefix is defined by setting
* this servlet's cgiPathPrefix init parameter
*
*
*
*
* CGI Specification:
derived from
* http://cgi-spec.golux.com.
* A work-in-progress & expired Internet Draft. Note no actual RFC describing
* the CGI specification exists. Where the behavior of this servlet differs
* from the specification cited above, it is either documented here, a bug,
* or an instance where the specification cited differs from Best
* Community Practice (BCP).
* Such instances should be well-documented here. Please email the
* Tomcat group [[email protected]]
* with amendments.
*
*
*
*
* Canonical metavariables:
* The CGI specification defines the following canonical metavariables:
*
* [excerpt from CGI specification]
*
* AUTH_TYPE
* CONTENT_LENGTH
* CONTENT_TYPE
* GATEWAY_INTERFACE
* PATH_INFO
* PATH_TRANSLATED
* QUERY_STRING
* REMOTE_ADDR
* REMOTE_HOST
* REMOTE_IDENT
* REMOTE_USER
* REQUEST_METHOD
* SCRIPT_NAME
* SERVER_NAME
* SERVER_PORT
* SERVER_PROTOCOL
* SERVER_SOFTWARE
*
*
* Metavariables with names beginning with the protocol name (e.g.,
* "HTTP_ACCEPT") are also canonical in their description of request header
* fields. The number and meaning of these fields may change independently
* of this specification. (See also section 6.1.5 [of the CGI specification].)
*
* [end excerpt]
*
*
* Implementation notes
*
*
* standard input handling: If your script accepts standard input,
* then the client must start sending input within a certain timeout period,
* otherwise the servlet will assume no input is coming and carry on running
* the script. The script's the standard input will be closed and handling of
* any further input from the client is undefined. Most likely it will be
* ignored. If this behavior becomes undesirable, then this servlet needs
* to be enhanced to handle threading of the spawned process' stdin, stdout,
* and stderr (which should not be too hard).
*
* If you find your cgi scripts are timing out receiving input, you can set
* the init parameter
*
*
* Metavariable Values: According to the CGI specification,
* implementations may choose to represent both null or missing values in an
* implementation-specific manner, but must define that manner. This
* implementation chooses to always define all required metavariables, but
* set the value to "" for all metavariables whose value is either null or
* undefined. PATH_TRANSLATED is the sole exception to this rule, as per the
* CGI Specification.
*
*
*
*
* NPH -- Non-parsed-header implementation: This implementation does
* not support the CGI NPH concept, whereby server ensures that the data
* supplied to the script are precisely as supplied by the client and
* unaltered by the server.
*
*
* The function of a servlet container (including Tomcat) is specifically
* designed to parse and possible alter CGI-specific variables, and as
* such makes NPH functionality difficult to support.
*
*
* The CGI specification states that compliant servers MAY support NPH output.
* It does not state servers MUST support NPH output to be unconditionally
* compliant. Thus, this implementation maintains unconditional compliance
* with the specification though NPH support is not present.
*
*
*
* The CGI specification is located at
* http://cgi-spec.golux.com.
*
*
*
*
TODO:
*
* - Support for setting headers (for example, Location headers don't work)
*
- Support for collapsing multiple header lines (per RFC 2616)
*
- Ensure handling of POST method does not interfere with 2.3 Filters
*
- Refactor some debug code out of core
*
- Ensure header handling preserves encoding
*
- Possibly rewrite CGIRunner.run()?
*
- Possibly refactor CGIRunner and CGIEnvironment as non-inner classes?
*
- Document handling of cgi stdin when there is no stdin
*
- Revisit IOException handling in CGIRunner.run()
*
- Better documentation
*
- Confirm use of ServletInputStream.available() in CGIRunner.run() is
* not needed
*
- [add more to this TODO list]
*
*
*
* @author Martin T Dengler [[email protected]]
* @author Amy Roh
* @since Tomcat 4.0
*/
public final class CGIServlet extends HttpServlet {
/* some vars below copied from Craig R. McClanahan's InvokerServlet */
private static final long serialVersionUID = 1L;
/** the debugging detail level for this servlet. */
private int debug = 0;
/**
* The CGI search path will start at
* webAppRootDir + File.separator + cgiPathPrefix
* (or webAppRootDir alone if cgiPathPrefix is
* null)
*/
private String cgiPathPrefix = null;
/** the executable to use with the script */
private String cgiExecutable = "perl";
/** additional arguments for the executable */
private List cgiExecutableArgs = null;
/** the encoding to use for parameters */
private String parameterEncoding =
System.getProperty("file.encoding", "UTF-8");
/**
* The time (in milliseconds) to wait for the reading of stderr to complete
* before terminating the CGI process.
*/
private long stderrTimeout = 2000;
/** object used to ensure multiple threads don't try to expand same file */
private static final Object expandFileLock = new Object();
/** the shell environment variables to be passed to the CGI script */
private final Hashtable shellEnv = new Hashtable<>();
/**
* Sets instance variables.
*
* Modified from Craig R. McClanahan's InvokerServlet
*
*
* @param config a ServletConfig object
* containing the servlet's
* configuration and initialization
* parameters
*
* @exception ServletException if an exception has occurred that
* interferes with the servlet's normal
* operation
*/
@Override
public void init(ServletConfig config) throws ServletException {
super.init(config);
// Set our properties from the initialization parameters
if (getServletConfig().getInitParameter("debug") != null)
debug = Integer.parseInt(getServletConfig().getInitParameter("debug"));
cgiPathPrefix = getServletConfig().getInitParameter("cgiPathPrefix");
boolean passShellEnvironment =
Boolean.valueOf(getServletConfig().getInitParameter("passShellEnvironment")).booleanValue();
if (passShellEnvironment) {
shellEnv.putAll(System.getenv());
}
if (getServletConfig().getInitParameter("executable") != null) {
cgiExecutable = getServletConfig().getInitParameter("executable");
}
if (getServletConfig().getInitParameter("executable-arg-1") != null) {
List args = new ArrayList<>();
for (int i = 1;; i++) {
String arg = getServletConfig().getInitParameter(
"executable-arg-" + i);
if (arg == null) {
break;
}
args.add(arg);
}
cgiExecutableArgs = args;
}
if (getServletConfig().getInitParameter("parameterEncoding") != null) {
parameterEncoding = getServletConfig().getInitParameter("parameterEncoding");
}
if (getServletConfig().getInitParameter("stderrTimeout") != null) {
stderrTimeout = Long.parseLong(getServletConfig().getInitParameter(
"stderrTimeout"));
}
}
/**
* Prints out important Servlet API and container information
*
*
* Copied from SnoopAllServlet by Craig R. McClanahan
*
*
* @param out ServletOutputStream as target of the information
* @param req HttpServletRequest object used as source of information
* @param res HttpServletResponse object currently not used but could
* provide future information
*
* @exception IOException if a write operation exception occurs
*
*/
protected void printServletEnvironment(ServletOutputStream out,
HttpServletRequest req, HttpServletResponse res)
throws IOException {
// Document the properties from ServletRequest
out.println("ServletRequest Properties
");
out.println("");
Enumeration attrs = req.getAttributeNames();
while (attrs.hasMoreElements()) {
String attr = attrs.nextElement();
out.println("- attribute " + attr + " = " +
req.getAttribute(attr));
}
out.println("
- characterEncoding = " +
req.getCharacterEncoding());
out.println("
- contentLength = " +
req.getContentLength());
out.println("
- contentType = " +
req.getContentType());
Enumeration
locales = req.getLocales();
while (locales.hasMoreElements()) {
Locale locale = locales.nextElement();
out.println("- locale = " + locale);
}
Enumeration
params = req.getParameterNames();
while (params.hasMoreElements()) {
String param = params.nextElement();
String values[] = req.getParameterValues(param);
for (int i = 0; i < values.length; i++)
out.println("- parameter " + param + " = " +
values[i]);
}
out.println("
- protocol = " + req.getProtocol());
out.println("
- remoteAddr = " + req.getRemoteAddr());
out.println("
- remoteHost = " + req.getRemoteHost());
out.println("
- scheme = " + req.getScheme());
out.println("
- secure = " + req.isSecure());
out.println("
- serverName = " + req.getServerName());
out.println("
- serverPort = " + req.getServerPort());
out.println("
");
out.println("
");
// Document the properties from HttpServletRequest
out.println("HttpServletRequest Properties
");
out.println("");
out.println("- authType = " + req.getAuthType());
out.println("
- contextPath = " +
req.getContextPath());
Cookie cookies[] = req.getCookies();
if (cookies!=null) {
for (int i = 0; i < cookies.length; i++)
out.println("
- cookie " + cookies[i].getName() +" = " +cookies[i].getValue());
}
Enumeration
headers = req.getHeaderNames();
while (headers.hasMoreElements()) {
String header = headers.nextElement();
out.println("- header " + header + " = " +
req.getHeader(header));
}
out.println("
- method = " + req.getMethod());
out.println("
- pathInfo = "
+ req.getPathInfo());
out.println("
- pathTranslated = " +
req.getPathTranslated());
out.println("
- queryString = " +
req.getQueryString());
out.println("
- remoteUser = " +
req.getRemoteUser());
out.println("
- requestedSessionId = " +
req.getRequestedSessionId());
out.println("
- requestedSessionIdFromCookie = " +
req.isRequestedSessionIdFromCookie());
out.println("
- requestedSessionIdFromURL = " +
req.isRequestedSessionIdFromURL());
out.println("
- requestedSessionIdValid = " +
req.isRequestedSessionIdValid());
out.println("
- requestURI = " +
req.getRequestURI());
out.println("
- servletPath = " +
req.getServletPath());
out.println("
- userPrincipal = " +
req.getUserPrincipal());
out.println("
");
out.println("
");
// Document the servlet request attributes
out.println("ServletRequest Attributes
");
out.println("");
attrs = req.getAttributeNames();
while (attrs.hasMoreElements()) {
String attr = attrs.nextElement();
out.println("- " + attr + " = " +
req.getAttribute(attr));
}
out.println("
");
out.println("
");
// Process the current session (if there is one)
HttpSession session = req.getSession(false);
if (session != null) {
// Document the session properties
out.println("HttpSession Properties
");
out.println("");
out.println("- id = " +
session.getId());
out.println("
- creationTime = " +
new Date(session.getCreationTime()));
out.println("
- lastAccessedTime = " +
new Date(session.getLastAccessedTime()));
out.println("
- maxInactiveInterval = " +
session.getMaxInactiveInterval());
out.println("
");
out.println("
");
// Document the session attributes
out.println("HttpSession Attributes
");
out.println("");
attrs = session.getAttributeNames();
while (attrs.hasMoreElements()) {
String attr = attrs.nextElement();
out.println("- " + attr + " = " +
session.getAttribute(attr));
}
out.println("
");
out.println("
");
}
// Document the servlet configuration properties
out.println("ServletConfig Properties
");
out.println("");
out.println("- servletName = " +
getServletConfig().getServletName());
out.println("
");
out.println("
");
// Document the servlet configuration initialization parameters
out.println("ServletConfig Initialization Parameters
");
out.println("");
params = getServletConfig().getInitParameterNames();
while (params.hasMoreElements()) {
String param = params.nextElement();
String value = getServletConfig().getInitParameter(param);
out.println("- " + param + " = " + value);
}
out.println("
");
out.println("
");
// Document the servlet context properties
out.println("ServletContext Properties
");
out.println("");
out.println("- majorVersion = " +
getServletContext().getMajorVersion());
out.println("
- minorVersion = " +
getServletContext().getMinorVersion());
out.println("
- realPath('/') = " +
getServletContext().getRealPath("/"));
out.println("
- serverInfo = " +
getServletContext().getServerInfo());
out.println("
");
out.println("
");
// Document the servlet context initialization parameters
out.println("ServletContext Initialization Parameters
");
out.println("");
params = getServletContext().getInitParameterNames();
while (params.hasMoreElements()) {
String param = params.nextElement();
String value = getServletContext().getInitParameter(param);
out.println("- " + param + " = " + value);
}
out.println("
");
out.println("
");
// Document the servlet context attributes
out.println("ServletContext Attributes
");
out.println("");
attrs = getServletContext().getAttributeNames();
while (attrs.hasMoreElements()) {
String attr = attrs.nextElement();
out.println("- " + attr + " = " +
getServletContext().getAttribute(attr));
}
out.println("
");
out.println("
");
}
/**
* Provides CGI Gateway service -- delegates to doGet
*
* @param req HttpServletRequest passed in by servlet container
* @param res HttpServletResponse passed in by servlet container
*
* @exception ServletException if a servlet-specific exception occurs
* @exception IOException if a read/write exception occurs
*
* @see javax.servlet.http.HttpServlet
*
*/
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse res)
throws IOException, ServletException {
doGet(req, res);
}
/**
* Provides CGI Gateway service
*
* @param req HttpServletRequest passed in by servlet container
* @param res HttpServletResponse passed in by servlet container
*
* @exception ServletException if a servlet-specific exception occurs
* @exception IOException if a read/write exception occurs
*
* @see javax.servlet.http.HttpServlet
*
*/
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
CGIEnvironment cgiEnv = new CGIEnvironment(req, getServletContext());
if (cgiEnv.isValid()) {
CGIRunner cgi = new CGIRunner(cgiEnv.getCommand(),
cgiEnv.getEnvironment(),
cgiEnv.getWorkingDirectory(),
cgiEnv.getParameters());
//if POST, we need to cgi.setInput
//REMIND: how does this interact with Servlet API 2.3's Filters?!
if ("POST".equals(req.getMethod())) {
cgi.setInput(req.getInputStream());
}
cgi.setResponse(res);
cgi.run();
}
if (!cgiEnv.isValid()) {
res.setStatus(404);
}
if (debug >= 10) {
ServletOutputStream out = res.getOutputStream();
out.println("$Name$ ");
out.println("$Header$");
if (cgiEnv.isValid()) {
out.println(cgiEnv.toString());
} else {
out.println("
");
out.println("CGI script not found or not specified.");
out.println("
");
out.println("");
out.println("Check the HttpServletRequest ");
out.println("pathInfo ");
out.println("property to see if it is what you meant ");
out.println("it to be. You must specify an existant ");
out.println("and executable file as part of the ");
out.println("path-info.");
out.println("
");
out.println("");
out.println("For a good discussion of how CGI scripts ");
out.println("work and what their environment variables ");
out.println("mean, please visit the CGI ");
out.println("Specification page.");
out.println("
");
}
printServletEnvironment(out, req, res);
out.println("");
}
} //doGet
/**
* Encapsulates the CGI environment and rules to derive
* that environment from the servlet container and request information.
*
*
*
*
* @since Tomcat 4.0
*/
protected class CGIEnvironment {
/** context of the enclosing servlet */
private ServletContext context = null;
/** context path of enclosing servlet */
private String contextPath = null;
/** servlet URI of the enclosing servlet */
private String servletPath = null;
/** pathInfo for the current request */
private String pathInfo = null;
/** real file system directory of the enclosing servlet's web app */
private String webAppRootDir = null;
/** tempdir for context - used to expand scripts in unexpanded wars */
private File tmpDir = null;
/** derived cgi environment */
private Hashtable env = null;
/** cgi command to be invoked */
private String command = null;
/** cgi command's desired working directory */
private final File workingDirectory;
/** cgi command's command line parameters */
private final ArrayList cmdLineParameters = new ArrayList<>();
/** whether or not this object is valid or not */
private final boolean valid;
/**
* Creates a CGIEnvironment and derives the necessary environment,
* query parameters, working directory, cgi command, etc.
*
* @param req HttpServletRequest for information provided by
* the Servlet API
* @param context ServletContext for information provided by the
* Servlet API
*
*/
protected CGIEnvironment(HttpServletRequest req,
ServletContext context) throws IOException {
setupFromContext(context);
setupFromRequest(req);
this.valid = setCGIEnvironment(req);
if (this.valid) {
workingDirectory = new File(command.substring(0,
command.lastIndexOf(File.separator)));
} else {
workingDirectory = null;
}
}
/**
* Uses the ServletContext to set some CGI variables
*
* @param context ServletContext for information provided by the
* Servlet API
*/
protected void setupFromContext(ServletContext context) {
this.context = context;
this.webAppRootDir = context.getRealPath("/");
this.tmpDir = (File) context.getAttribute(ServletContext.TEMPDIR);
}
/**
* Uses the HttpServletRequest to set most CGI variables
*
* @param req HttpServletRequest for information provided by
* the Servlet API
* @throws UnsupportedEncodingException
*/
protected void setupFromRequest(HttpServletRequest req)
throws UnsupportedEncodingException {
boolean isIncluded = false;
// Look to see if this request is an include
if (req.getAttribute(
RequestDispatcher.INCLUDE_REQUEST_URI) != null) {
isIncluded = true;
}
if (isIncluded) {
this.contextPath = (String) req.getAttribute(
RequestDispatcher.INCLUDE_CONTEXT_PATH);
this.servletPath = (String) req.getAttribute(
RequestDispatcher.INCLUDE_SERVLET_PATH);
this.pathInfo = (String) req.getAttribute(
RequestDispatcher.INCLUDE_PATH_INFO);
} else {
this.contextPath = req.getContextPath();
this.servletPath = req.getServletPath();
this.pathInfo = req.getPathInfo();
}
// If getPathInfo() returns null, must be using extension mapping
// In this case, pathInfo should be same as servletPath
if (this.pathInfo == null) {
this.pathInfo = this.servletPath;
}
// If the request method is GET, POST or HEAD and the query string
// does not contain an unencoded "=" this is an indexed query.
// The parsed query string becomes the command line parameters
// for the cgi command.
if (req.getMethod().equals("GET")
|| req.getMethod().equals("POST")
|| req.getMethod().equals("HEAD")) {
String qs;
if (isIncluded) {
qs = (String) req.getAttribute(
RequestDispatcher.INCLUDE_QUERY_STRING);
} else {
qs = req.getQueryString();
}
if (qs != null && qs.indexOf("=") == -1) {
StringTokenizer qsTokens = new StringTokenizer(qs, "+");
while ( qsTokens.hasMoreTokens() ) {
cmdLineParameters.add(URLDecoder.decode(qsTokens.nextToken(),
parameterEncoding));
}
}
}
}
/**
* Resolves core information about the cgi script.
*
*
* Example URI:
*
/servlet/cgigateway/dir1/realCGIscript/pathinfo1
*
* - path = $CATALINA_HOME/mywebapp/dir1/realCGIscript
*
- scriptName = /servlet/cgigateway/dir1/realCGIscript
*
- cgiName = /dir1/realCGIscript
*
- name = realCGIscript
*
*
*
* CGI search algorithm: search the real path below
* <my-webapp-root> and find the first non-directory in
* the getPathTranslated("/"), reading/searching from left-to-right.
*
*
* The CGI search path will start at
* webAppRootDir + File.separator + cgiPathPrefix
* (or webAppRootDir alone if cgiPathPrefix is
* null).
*
*
* cgiPathPrefix is defined by setting
* this servlet's cgiPathPrefix init parameter
*
*
*
* @param pathInfo String from HttpServletRequest.getPathInfo()
* @param webAppRootDir String from context.getRealPath("/")
* @param contextPath String as from
* HttpServletRequest.getContextPath()
* @param servletPath String as from
* HttpServletRequest.getServletPath()
* @param cgiPathPrefix subdirectory of webAppRootDir below which
* the web app's CGIs may be stored; can be null.
* The CGI search path will start at
* webAppRootDir + File.separator + cgiPathPrefix
* (or webAppRootDir alone if cgiPathPrefix is
* null). cgiPathPrefix is defined by setting
* the servlet's cgiPathPrefix init parameter.
*
*
* @return
*
* -
*
path - full file-system path to valid cgi script,
* or null if no cgi was found
* -
*
scriptName -
* CGI variable SCRIPT_NAME; the full URL path
* to valid cgi script or null if no cgi was
* found
* -
*
cgiName - servlet pathInfo fragment corresponding to
* the cgi script itself, or null if not found
* -
*
name - simple name (no directories) of the
* cgi script, or null if no cgi was found
*
*
* @since Tomcat 4.0
*/
protected String[] findCGI(String pathInfo, String webAppRootDir,
String contextPath, String servletPath,
String cgiPathPrefix) {
String path = null;
String name = null;
String scriptname = null;
String cginame = "";
if ((webAppRootDir != null)
&& (webAppRootDir.lastIndexOf(File.separator) ==
(webAppRootDir.length() - 1))) {
//strip the trailing "/" from the webAppRootDir
webAppRootDir =
webAppRootDir.substring(0, (webAppRootDir.length() - 1));
}
if (cgiPathPrefix != null) {
webAppRootDir = webAppRootDir + File.separator
+ cgiPathPrefix;
}
if (debug >= 2) {
log("findCGI: path=" + pathInfo + ", " + webAppRootDir);
}
File currentLocation = new File(webAppRootDir);
StringTokenizer dirWalker =
new StringTokenizer(pathInfo, "/");
if (debug >= 3) {
log("findCGI: currentLoc=" + currentLocation);
}
while (!currentLocation.isFile() && dirWalker.hasMoreElements()) {
if (debug >= 3) {
log("findCGI: currentLoc=" + currentLocation);
}
String nextElement = (String) dirWalker.nextElement();
currentLocation = new File(currentLocation, nextElement);
cginame = cginame + "/" + nextElement;
}
if (!currentLocation.isFile()) {
return new String[] { null, null, null, null };
}
if (debug >= 2) {
log("findCGI: FOUND cgi at " + currentLocation);
}
path = currentLocation.getAbsolutePath();
name = currentLocation.getName();
if (".".equals(contextPath)) {
scriptname = servletPath;
} else {
scriptname = contextPath + servletPath;
}
if (!servletPath.equals(cginame)) {
scriptname = scriptname + cginame;
}
if (debug >= 1) {
log("findCGI calc: name=" + name + ", path=" + path
+ ", scriptname=" + scriptname + ", cginame=" + cginame);
}
return new String[] { path, scriptname, cginame, name };
}
/**
* Constructs the CGI environment to be supplied to the invoked CGI
* script; relies heavily on Servlet API methods and findCGI
*
* @param req request associated with the CGI
* Invocation
*
* @return true if environment was set OK, false if there
* was a problem and no environment was set
*/
protected boolean setCGIEnvironment(HttpServletRequest req) throws IOException {
/*
* This method is slightly ugly; c'est la vie.
* "You cannot stop [ugliness], you can only hope to contain [it]"
* (apologies to Marv Albert regarding MJ)
*/
Hashtable envp = new Hashtable<>();
// Add the shell environment variables (if any)
envp.putAll(shellEnv);
// Add the CGI environment variables
String sPathInfoOrig = null;
String sPathInfoCGI = null;
String sPathTranslatedCGI = null;
String sCGIFullPath = null;
String sCGIScriptName = null;
String sCGIFullName = null;
String sCGIName = null;
String[] sCGINames;
sPathInfoOrig = this.pathInfo;
sPathInfoOrig = sPathInfoOrig == null ? "" : sPathInfoOrig;
if (webAppRootDir == null ) {
// The app has not been deployed in exploded form
webAppRootDir = tmpDir.toString();
expandCGIScript();
}
sCGINames = findCGI(sPathInfoOrig,
webAppRootDir,
contextPath,
servletPath,
cgiPathPrefix);
sCGIFullPath = sCGINames[0];
sCGIScriptName = sCGINames[1];
sCGIFullName = sCGINames[2];
sCGIName = sCGINames[3];
if (sCGIFullPath == null
|| sCGIScriptName == null
|| sCGIFullName == null
|| sCGIName == null) {
return false;
}
envp.put("SERVER_SOFTWARE", "TOMCAT");
envp.put("SERVER_NAME", nullsToBlanks(req.getServerName()));
envp.put("GATEWAY_INTERFACE", "CGI/1.1");
envp.put("SERVER_PROTOCOL", nullsToBlanks(req.getProtocol()));
int port = req.getServerPort();
Integer iPort =
(port == 0 ? Integer.valueOf(-1) : Integer.valueOf(port));
envp.put("SERVER_PORT", iPort.toString());
envp.put("REQUEST_METHOD", nullsToBlanks(req.getMethod()));
envp.put("REQUEST_URI", nullsToBlanks(req.getRequestURI()));
/*-
* PATH_INFO should be determined by using sCGIFullName:
* 1) Let sCGIFullName not end in a "/" (see method findCGI)
* 2) Let sCGIFullName equal the pathInfo fragment which
* corresponds to the actual cgi script.
* 3) Thus, PATH_INFO = request.getPathInfo().substring(
* sCGIFullName.length())
*
* (see method findCGI, where the real work is done)
*
*/
if (pathInfo == null
|| (pathInfo.substring(sCGIFullName.length()).length() <= 0)) {
sPathInfoCGI = "";
} else {
sPathInfoCGI = pathInfo.substring(sCGIFullName.length());
}
envp.put("PATH_INFO", sPathInfoCGI);
/*-
* PATH_TRANSLATED must be determined after PATH_INFO (and the
* implied real cgi-script) has been taken into account.
*
* The following example demonstrates:
*
* servlet info = /servlet/cgigw/dir1/dir2/cgi1/trans1/trans2
* cgifullpath = /servlet/cgigw/dir1/dir2/cgi1
* path_info = /trans1/trans2
* webAppRootDir = servletContext.getRealPath("/")
*
* path_translated = servletContext.getRealPath("/trans1/trans2")
*
* That is, PATH_TRANSLATED = webAppRootDir + sPathInfoCGI
* (unless sPathInfoCGI is null or blank, then the CGI
* specification dictates that the PATH_TRANSLATED metavariable
* SHOULD NOT be defined.
*
*/
if (sPathInfoCGI != null && !("".equals(sPathInfoCGI))) {
sPathTranslatedCGI = context.getRealPath(sPathInfoCGI);
}
if (sPathTranslatedCGI == null || "".equals(sPathTranslatedCGI)) {
//NOOP
} else {
envp.put("PATH_TRANSLATED", nullsToBlanks(sPathTranslatedCGI));
}
envp.put("SCRIPT_NAME", nullsToBlanks(sCGIScriptName));
envp.put("QUERY_STRING", nullsToBlanks(req.getQueryString()));
envp.put("REMOTE_HOST", nullsToBlanks(req.getRemoteHost()));
envp.put("REMOTE_ADDR", nullsToBlanks(req.getRemoteAddr()));
envp.put("AUTH_TYPE", nullsToBlanks(req.getAuthType()));
envp.put("REMOTE_USER", nullsToBlanks(req.getRemoteUser()));
envp.put("REMOTE_IDENT", ""); //not necessary for full compliance
envp.put("CONTENT_TYPE", nullsToBlanks(req.getContentType()));
/* Note CGI spec says CONTENT_LENGTH must be NULL ("") or undefined
* if there is no content, so we cannot put 0 or -1 in as per the
* Servlet API spec.
*/
int contentLength = req.getContentLength();
String sContentLength = (contentLength <= 0 ? "" :
(Integer.valueOf(contentLength)).toString());
envp.put("CONTENT_LENGTH", sContentLength);
Enumeration headers = req.getHeaderNames();
String header = null;
while (headers.hasMoreElements()) {
header = null;
header = headers.nextElement().toUpperCase(Locale.ENGLISH);
//REMIND: rewrite multiple headers as if received as single
//REMIND: change character set
//REMIND: I forgot what the previous REMIND means
if ("AUTHORIZATION".equalsIgnoreCase(header) ||
"PROXY_AUTHORIZATION".equalsIgnoreCase(header)) {
//NOOP per CGI specification section 11.2
} else {
envp.put("HTTP_" + header.replace('-', '_'),
req.getHeader(header));
}
}
File fCGIFullPath = new File(sCGIFullPath);
command = fCGIFullPath.getCanonicalPath();
envp.put("X_TOMCAT_SCRIPT_PATH", command); //for kicks
envp.put("SCRIPT_FILENAME", command); //for PHP
this.env = envp;
return true;
}
/**
* Extracts requested resource from web app archive to context work
* directory to enable CGI script to be executed.
*/
protected void expandCGIScript() {
StringBuilder srcPath = new StringBuilder();
StringBuilder destPath = new StringBuilder();
InputStream is = null;
// paths depend on mapping
if (cgiPathPrefix == null ) {
srcPath.append(pathInfo);
is = context.getResourceAsStream(srcPath.toString());
destPath.append(tmpDir);
destPath.append(pathInfo);
} else {
// essentially same search algorithm as findCGI()
srcPath.append(cgiPathPrefix);
StringTokenizer pathWalker =
new StringTokenizer (pathInfo, "/");
// start with first element
while (pathWalker.hasMoreElements() && (is == null)) {
srcPath.append("/");
srcPath.append(pathWalker.nextElement());
is = context.getResourceAsStream(srcPath.toString());
}
destPath.append(tmpDir);
destPath.append("/");
destPath.append(srcPath);
}
if (is == null) {
// didn't find anything, give up now
if (debug >= 2) {
log("expandCGIScript: source '" + srcPath + "' not found");
}
return;
}
File f = new File(destPath.toString());
if (f.exists()) {
// Don't need to expand if it already exists
return;
}
// create directories
String dirPath = destPath.toString().substring(
0,destPath.toString().lastIndexOf("/"));
File dir = new File(dirPath);
if (!dir.mkdirs() && !dir.isDirectory()) {
if (debug >= 2) {
log("expandCGIScript: failed to create directories for '" +
dir.getAbsolutePath() + "'");
}
return;
}
try {
synchronized (expandFileLock) {
// make sure file doesn't exist
if (f.exists()) {
return;
}
// create file
if (!f.createNewFile()) {
return;
}
FileOutputStream fos = new FileOutputStream(f);
// copy data
IOTools.flow(is, fos);
is.close();
fos.close();
if (debug >= 2) {
log("expandCGIScript: expanded '" + srcPath + "' to '" + destPath + "'");
}
}
} catch (IOException ioe) {
// delete in case file is corrupted
if (f.exists()) {
if (!f.delete() && debug >= 2) {
log("expandCGIScript: failed to delete '" +
f.getAbsolutePath() + "'");
}
}
}
}
/**
* Print important CGI environment information in a easy-to-read HTML
* table
*
* @return HTML string containing CGI environment info
*
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("");
sb.append("");
sb.append("CGIEnvironment Info Debug Level ");
sb.append(debug);
sb.append(" Validity: ");
sb.append(isValid());
sb.append(" envk = env.keys();
while (envk.hasMoreElements()) {
String s = envk.nextElement();
sb.append("");
sb.append(s);
sb.append(" ");
sb.append(blanksToString(env.get(s),
"[will be set to blank]"));
sb.append("
Derived Command ");
sb.append(nullsToBlanks(command));
sb.append(" Working Directory ");
if (workingDirectory != null) {
sb.append(workingDirectory.toString());
}
sb.append(" Command Line Params ");
for (int i=0; i < cmdLineParameters.size(); i++) {
String param = cmdLineParameters.get(i);
sb.append("");
sb.append(param);
sb.append("
");
}
sb.append("
end.");
return sb.toString();
}
/**
* Gets derived command string
*
* @return command string
*
*/
protected String getCommand() {
return command;
}
/**
* Gets derived CGI working directory
*
* @return working directory
*
*/
protected File getWorkingDirectory() {
return workingDirectory;
}
/**
* Gets derived CGI environment
*
* @return CGI environment
*
*/
protected Hashtable getEnvironment() {
return env;
}
/**
* Gets derived CGI query parameters
*
* @return CGI query parameters
*
*/
protected ArrayList getParameters() {
return cmdLineParameters;
}
/**
* Gets validity status
*
* @return true if this environment is valid, false
* otherwise
*
*/
protected boolean isValid() {
return valid;
}
/**
* Converts null strings to blank strings ("")
*
* @param s string to be converted if necessary
* @return a non-null string, either the original or the empty string
* ("") if the original was null
*/
protected String nullsToBlanks(String s) {
return nullsToString(s, "");
}
/**
* Converts null strings to another string
*
* @param couldBeNull string to be converted if necessary
* @param subForNulls string to return instead of a null string
* @return a non-null string, either the original or the substitute
* string if the original was null
*/
protected String nullsToString(String couldBeNull,
String subForNulls) {
return (couldBeNull == null ? subForNulls : couldBeNull);
}
/**
* Converts blank strings to another string
*
* @param couldBeBlank string to be converted if necessary
* @param subForBlanks string to return instead of a blank string
* @return a non-null string, either the original or the substitute
* string if the original was null or empty ("")
*/
protected String blanksToString(String couldBeBlank,
String subForBlanks) {
return (("".equals(couldBeBlank) || couldBeBlank == null)
? subForBlanks
: couldBeBlank);
}
} //class CGIEnvironment
/**
* Encapsulates the knowledge of how to run a CGI script, given the
* script's desired environment and (optionally) input/output streams
*
*
*
* Exposes a run method used to actually invoke the
* CGI.
*
*
*
*
* The CGI environment and settings are derived from the information
* passed to the constructor.
*
*
*
*
* The input and output streams can be set by the setInput
* and setResponse methods, respectively.
*
*/
protected class CGIRunner {
/** script/command to be executed */
private final String command;
/** environment used when invoking the cgi script */
private final Hashtable env;
/** working directory used when invoking the cgi script */
private final File wd;
/** command line parameters to be passed to the invoked script */
private final ArrayList params;
/** stdin to be passed to cgi script */
private InputStream stdin = null;
/** response object used to set headers & get output stream */
private HttpServletResponse response = null;
/** boolean tracking whether this object has enough info to run() */
private boolean readyToRun = false;
/**
* Creates a CGIRunner and initializes its environment, working
* directory, and query parameters.
*
* Input/output streams (optional) are set using the
* setInput and setResponse methods,
* respectively.
*
* @param command string full path to command to be executed
* @param env Hashtable with the desired script environment
* @param wd File with the script's desired working directory
* @param params ArrayList with the script's query command line
* parameters as strings
*/
protected CGIRunner(String command, Hashtable env,
File wd, ArrayList params) {
this.command = command;
this.env = env;
this.wd = wd;
this.params = params;
updateReadyStatus();
}
/**
* Checks & sets ready status
*/
protected void updateReadyStatus() {
if (command != null
&& env != null
&& wd != null
&& params != null
&& response != null) {
readyToRun = true;
} else {
readyToRun = false;
}
}
/**
* Gets ready status
*
* @return false if not ready (run will throw
* an exception), true if ready
*/
protected boolean isReady() {
return readyToRun;
}
/**
* Sets HttpServletResponse object used to set headers and send
* output to
*
* @param response HttpServletResponse to be used
*
*/
protected void setResponse(HttpServletResponse response) {
this.response = response;
updateReadyStatus();
}
/**
* Sets standard input to be passed on to the invoked cgi script
*
* @param stdin InputStream to be used
*
*/
protected void setInput(InputStream stdin) {
this.stdin = stdin;
updateReadyStatus();
}
/**
* Converts a Hashtable to a String array by converting each
* key/value pair in the Hashtable to a String in the form
* "key=value" (hashkey + "=" + hash.get(hashkey).toString())
*
* @param h Hashtable to convert
*
* @return converted string array
*
* @exception NullPointerException if a hash key has a null value
*
*/
protected String[] hashToStringArray(Hashtable h)
throws NullPointerException {
Vector v = new Vector<>();
Enumeration e = h.keys();
while (e.hasMoreElements()) {
String k = e.nextElement();
v.add(k + "=" + h.get(k).toString());
}
String[] strArr = new String[v.size()];
v.copyInto(strArr);
return strArr;
}
/**
* Executes a CGI script with the desired environment, current working
* directory, and input/output streams
*
*
* This implements the following CGI specification recommedations:
*
* - Servers SHOULD provide the "
query" component of
* the script-URI as command-line arguments to scripts if it
* does not contain any unencoded "=" characters and the
* command-line arguments can be generated in an unambiguous
* manner.
* - Servers SHOULD set the AUTH_TYPE metavariable to the value
* of the "
auth-scheme" token of the
* "Authorization" if it was supplied as part of the
* request header. See getCGIEnvironment method.
* - Where applicable, servers SHOULD set the current working
* directory to the directory in which the script is located
* before invoking it.
*
- Server implementations SHOULD define their behavior for the
* following cases:
*
* - Allowed characters in pathInfo: This implementation
* does not allow ASCII NUL nor any character which cannot
* be URL-encoded according to internet standards;
*
- Allowed characters in path segments: This
* implementation does not allow non-terminal NULL
* segments in the the path -- IOExceptions may be thrown;
*
- "
." and ".." path
* segments:
* This implementation does not allow "." and
* ".." in the the path, and such characters
* will result in an IOException being thrown (this should
* never happen since Tomcat normalises the requestURI
* before determining the contextPath, servletPath and
* pathInfo);
* - Implementation limitations: This implementation
* does not impose any limitations except as documented
* above. This implementation may be limited by the
* servlet container used to house this implementation.
* In particular, all the primary CGI variable values
* are derived either directly or indirectly from the
* container's implementation of the Servlet API methods.
*
*
*
*
* @exception IOException if problems during reading/writing occur
*
* @see java.lang.Runtime#exec(String command, String[] envp,
* File dir)
*/
protected void run() throws IOException {
/*
* REMIND: this method feels too big; should it be re-written?
*/
if (!isReady()) {
throw new IOException(this.getClass().getName()
+ ": not ready to run.");
}
if (debug >= 1 ) {
log("runCGI(envp=[" + env + "], command=" + command + ")");
}
if ((command.indexOf(File.separator + "." + File.separator) >= 0)
|| (command.indexOf(File.separator + "..") >= 0)
|| (command.indexOf(".." + File.separator) >= 0)) {
throw new IOException(this.getClass().getName()
+ "Illegal Character in CGI command "
+ "path ('.' or '..') detected. Not "
+ "running CGI [" + command + "].");
}
/* original content/structure of this section taken from
* http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4216884
* with major modifications by Martin Dengler
*/
Runtime rt = null;
BufferedReader cgiHeaderReader = null;
InputStream cgiOutput = null;
BufferedReader commandsStdErr = null;
Thread errReaderThread = null;
BufferedOutputStream commandsStdIn = null;
Process proc = null;
int bufRead = -1;
List cmdAndArgs = new ArrayList<>();
if (cgiExecutable.length() != 0) {
cmdAndArgs.add(cgiExecutable);
}
if (cgiExecutableArgs != null) {
cmdAndArgs.addAll(cgiExecutableArgs);
}
cmdAndArgs.add(command);
cmdAndArgs.addAll(params);
try {
rt = Runtime.getRuntime();
proc = rt.exec(
cmdAndArgs.toArray(new String[cmdAndArgs.size()]),
hashToStringArray(env), wd);
String sContentLength = env.get("CONTENT_LENGTH");
if(!"".equals(sContentLength)) {
commandsStdIn = new BufferedOutputStream(proc.getOutputStream());
IOTools.flow(stdin, commandsStdIn);
commandsStdIn.flush();
commandsStdIn.close();
}
/* we want to wait for the process to exit, Process.waitFor()
* is useless in our situation; see
* http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4223650
*/
boolean isRunning = true;
commandsStdErr = new BufferedReader
(new InputStreamReader(proc.getErrorStream()));
final BufferedReader stdErrRdr = commandsStdErr ;
errReaderThread = new Thread() {
@Override
public void run () {
sendToLog(stdErrRdr) ;
}
};
errReaderThread.start();
InputStream cgiHeaderStream =
new HTTPHeaderInputStream(proc.getInputStream());
cgiHeaderReader =
new BufferedReader(new InputStreamReader(cgiHeaderStream));
while (isRunning) {
try {
//set headers
String line = null;
while (((line = cgiHeaderReader.readLine()) != null)
&& !("".equals(line))) {
if (debug >= 2) {
log("runCGI: addHeader(\"" + line + "\")");
}
if (line.startsWith("HTTP")) {
response.setStatus(getSCFromHttpStatusLine(line));
} else if (line.indexOf(":") >= 0) {
String header =
line.substring(0, line.indexOf(":")).trim();
String value =
line.substring(line.indexOf(":") + 1).trim();
if (header.equalsIgnoreCase("status")) {
response.setStatus(getSCFromCGIStatusHeader(value));
} else {
response.addHeader(header , value);
}
} else {
log("runCGI: bad header line \"" + line + "\"");
}
}
//write output
byte[] bBuf = new byte[2048];
OutputStream out = response.getOutputStream();
cgiOutput = proc.getInputStream();
try {
while ((bufRead = cgiOutput.read(bBuf)) != -1) {
if (debug >= 4) {
log("runCGI: output " + bufRead +
" bytes of data");
}
out.write(bBuf, 0, bufRead);
}
} finally {
// Attempt to consume any leftover byte if something bad happens,
// such as a socket disconnect on the servlet side; otherwise, the
// external process could hang
if (bufRead != -1) {
while ((bufRead = cgiOutput.read(bBuf)) != -1) {
// NOOP - just read the data
}
}
}
proc.exitValue(); // Throws exception if alive
isRunning = false;
} catch (IllegalThreadStateException e) {
try {
Thread.sleep(500);
} catch (InterruptedException ignored) {
// Ignore
}
}
} //replacement for Process.waitFor()
}
catch (IOException e){
log ("Caught exception " + e);
throw e;
}
finally{
// Close the header reader
if (cgiHeaderReader != null) {
try {
cgiHeaderReader.close();
} catch (IOException ioe) {
log ("Exception closing header reader " + ioe);
}
}
// Close the output stream if used
if (cgiOutput != null) {
try {
cgiOutput.close();
} catch (IOException ioe) {
log ("Exception closing output stream " + ioe);
}
}
// Make sure the error stream reader has finished
if (errReaderThread != null) {
try {
errReaderThread.join(stderrTimeout);
} catch (InterruptedException e) {
log ("Interupted waiting for stderr reader thread");
}
}
if (debug > 4) {
log ("Running finally block");
}
if (proc != null){
proc.destroy();
proc = null;
}
}
}
/**
* Parses the Status-Line and extracts the status code.
*
* @param line The HTTP Status-Line (RFC2616, section 6.1)
* @return The extracted status code or the code representing an
* internal error if a valid status code cannot be extracted.
*/
private int getSCFromHttpStatusLine(String line) {
int statusStart = line.indexOf(' ') + 1;
if (statusStart < 1 || line.length() < statusStart + 3) {
// Not a valid HTTP Status-Line
log ("runCGI: invalid HTTP Status-Line:" + line);
return HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
}
String status = line.substring(statusStart, statusStart + 3);
int statusCode;
try {
statusCode = Integer.parseInt(status);
} catch (NumberFormatException nfe) {
// Not a valid status code
log ("runCGI: invalid status code:" + status);
return HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
}
return statusCode;
}
/**
* Parses the CGI Status Header value and extracts the status code.
*
* @param value The CGI Status value of the form
* digit digit digit SP reason-phrase
* @return The extracted status code or the code representing an
* internal error if a valid status code cannot be extracted.
*/
private int getSCFromCGIStatusHeader(String value) {
if (value.length() < 3) {
// Not a valid status value
log ("runCGI: invalid status value:" + value);
return HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
}
String status = value.substring(0, 3);
int statusCode;
try {
statusCode = Integer.parseInt(status);
} catch (NumberFormatException nfe) {
// Not a valid status code
log ("runCGI: invalid status code:" + status);
return HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
}
return statusCode;
}
private void sendToLog(BufferedReader rdr) {
String line = null;
int lineCount = 0 ;
try {
while ((line = rdr.readLine()) != null) {
log("runCGI (stderr):" + line) ;
lineCount++ ;
}
} catch (IOException e) {
log("sendToLog error", e) ;
} finally {
try {
rdr.close() ;
} catch (IOException ce) {
log("sendToLog error", ce) ;
}
}
if ( lineCount > 0 && debug > 2) {
log("runCGI: " + lineCount + " lines received on stderr") ;
}
}
} //class CGIRunner
/**
* This is an input stream specifically for reading HTTP headers. It reads
* upto and including the two blank lines terminating the headers. It
* allows the content to be read using bytes or characters as appropriate.
*/
protected static class HTTPHeaderInputStream extends InputStream {
private static final int STATE_CHARACTER = 0;
private static final int STATE_FIRST_CR = 1;
private static final int STATE_FIRST_LF = 2;
private static final int STATE_SECOND_CR = 3;
private static final int STATE_HEADER_END = 4;
private final InputStream input;
private int state;
HTTPHeaderInputStream(InputStream theInput) {
input = theInput;
state = STATE_CHARACTER;
}
/**
* @see java.io.InputStream#read()
*/
@Override
public int read() throws IOException {
if (state == STATE_HEADER_END) {
return -1;
}
int i = input.read();
// Update the state
// State machine looks like this
//
// -------->--------
// | (CR) |
// | |
// CR1--->--- |
// | | |
// ^(CR) |(LF) |
// | | |
// CHAR--->--LF1--->--EOH
// (LF) | (LF) |
// |(CR) ^(LF)
// | |
// (CR2)-->---
if (i == 10) {
// LF
switch(state) {
case STATE_CHARACTER:
state = STATE_FIRST_LF;
break;
case STATE_FIRST_CR:
state = STATE_FIRST_LF;
break;
case STATE_FIRST_LF:
case STATE_SECOND_CR:
state = STATE_HEADER_END;
break;
}
} else if (i == 13) {
// CR
switch(state) {
case STATE_CHARACTER:
state = STATE_FIRST_CR;
break;
case STATE_FIRST_CR:
state = STATE_HEADER_END;
break;
case STATE_FIRST_LF:
state = STATE_SECOND_CR;
break;
}
} else {
state = STATE_CHARACTER;
}
return i;
}
} // class HTTPHeaderInputStream
} //class CGIServlet