Files
codeql/java/ql/test/experimental/query-tests/security/CWE-552/UnsafeLoadSpringResource.java

271 lines
8.8 KiB
Java

package com.example;
import java.io.File;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.Reader;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.nio.file.Files;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.ResourceLoader;
import org.springframework.util.ResourceUtils;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
/** Sample class of Spring RestController */
@RestController
public class UnsafeLoadSpringResource {
@GetMapping("/file1")
//BAD: Get resource from ClassPathResource without input validation
public String getFileContent1(@RequestParam(name="fileName") String fileName) {
// A request such as the following can disclose source code and application configuration
// fileName=/../../WEB-INF/views/page.jsp
// fileName=/com/example/package/SampleController.class
ClassPathResource clr = new ClassPathResource(fileName);
char[] buffer = new char[4096];
StringBuilder out = new StringBuilder();
try {
Reader in = new InputStreamReader(clr.getInputStream(), "UTF-8");
for (int numRead; (numRead = in.read(buffer, 0, buffer.length)) > 0; ) {
out.append(buffer, 0, numRead);
}
} catch (IOException ie) {
ie.printStackTrace();
}
return out.toString();
}
@GetMapping("/file1a")
//GOOD: Get resource from ClassPathResource with input path validation
public String getFileContent1a(@RequestParam(name="fileName") String fileName) {
String result = null;
if (!isInvalidPath(fileName) && !isInvalidEncodedPath(fileName)) {
ClassPathResource clr = new ClassPathResource(fileName);
char[] buffer = new char[4096];
StringBuilder out = new StringBuilder();
try {
Reader in = new InputStreamReader(clr.getInputStream(), "UTF-8");
for (int numRead; (numRead = in.read(buffer, 0, buffer.length)) > 0; ) {
out.append(buffer, 0, numRead);
}
} catch (IOException ie) {
ie.printStackTrace();
}
result = out.toString();
}
return result;
}
@GetMapping("/file2")
//BAD: Get resource from ResourceUtils without input validation
public String getFileContent2(@RequestParam(name="fileName") String fileName) {
String content = null;
try {
// A request such as the following can disclose source code and system configuration
// fileName=/etc/hosts
// fileName=file:/etc/hosts
// fileName=/opt/appdir/WEB-INF/views/page.jsp
File file = ResourceUtils.getFile(fileName);
//Read File Content
content = new String(Files.readAllBytes(file.toPath()));
} catch (IOException ie) {
ie.printStackTrace();
}
return content;
}
@GetMapping("/file2a")
//GOOD: Get resource from ResourceUtils with input path validation
public String getFileContent2a(@RequestParam(name="fileName") String fileName) {
String content = null;
if (!isInvalidPath(fileName) && !isInvalidEncodedPath(fileName)) {
try {
File file = ResourceUtils.getFile(fileName);
//Read File Content
content = new String(Files.readAllBytes(file.toPath()));
} catch (IOException ie) {
ie.printStackTrace();
}
}
return content;
}
@Autowired
ResourceLoader resourceLoader;
@GetMapping("/file3")
//BAD: Get resource from ResourceLoader (same as application context) without input validation
public String getFileContent3(@RequestParam(name="fileName") String fileName) {
String content = null;
try {
// A request such as the following can disclose source code and system configuration
// fileName=/WEB-INF/views/page.jsp
// fileName=/WEB-INF/classes/com/example/package/SampleController.class
// fileName=file:/etc/hosts
Resource resource = resourceLoader.getResource(fileName);
char[] buffer = new char[4096];
StringBuilder out = new StringBuilder();
Reader in = new InputStreamReader(resource.getInputStream(), "UTF-8");
for (int numRead; (numRead = in.read(buffer, 0, buffer.length)) > 0; ) {
out.append(buffer, 0, numRead);
}
content = out.toString();
} catch (IOException ie) {
ie.printStackTrace();
}
return content;
}
@GetMapping("/file3a")
//GOOD: Get resource from ResourceLoader (same as application context) with input path validation
public String getFileContent3a(@RequestParam(name="fileName") String fileName) {
String content = null;
if (!isInvalidPath(fileName) && !isInvalidEncodedPath(fileName)) {
try {
Resource resource = resourceLoader.getResource(fileName);
char[] buffer = new char[4096];
StringBuilder out = new StringBuilder();
Reader in = new InputStreamReader(resource.getInputStream(), "UTF-8");
for (int numRead; (numRead = in.read(buffer, 0, buffer.length)) > 0; ) {
out.append(buffer, 0, numRead);
}
content = out.toString();
} catch (IOException ie) {
ie.printStackTrace();
}
}
return content;
}
/**
* Check whether the given path contains invalid escape sequences.
* @param path the path to validate
* @return {@code true} if the path is invalid, {@code false} otherwise
* @see Referenced code for path validation fix in https://github.com/mpgn/CVE-2019-3799
*/
private boolean isInvalidEncodedPath(String path) {
if (path.contains("%")) {
try {
// Use URLDecoder (vs UriUtils) to preserve potentially decoded UTF-8 chars
String decodedPath = URLDecoder.decode(path, "UTF-8");
if (isInvalidPath(decodedPath)) {
return true;
}
decodedPath = processPath(decodedPath);
if (isInvalidPath(decodedPath)) {
return true;
}
} catch (IllegalArgumentException | UnsupportedEncodingException ex) {
// Should never happen...
}
}
return false;
}
/**
* Process the given resource path.
* <p>The default implementation replaces:
* <ul>
* <li>Backslash with forward slash.
* <li>Duplicate occurrences of slash with a single slash.
* <li>Any combination of leading slash and control characters (00-1F and 7F)
* with a single "/" or "". For example {@code " / // foo/bar"}
* becomes {@code "/foo/bar"}.
* </ul>
* @since 3.2.12
* @see Referenced code for path validation fix in https://github.com/mpgn/CVE-2019-3799
*/
protected String processPath(String path) {
path = StringUtils.replace(path, "\\", "/");
path = cleanDuplicateSlashes(path);
return cleanLeadingSlash(path);
}
/** @see Referenced code for path validation fix in https://github.com/mpgn/CVE-2019-3799 **/
private String cleanDuplicateSlashes(String path) {
StringBuilder sb = null;
char prev = 0;
for (int i = 0; i < path.length(); i++) {
char curr = path.charAt(i);
try {
if ((curr == '/') && (prev == '/')) {
if (sb == null) {
sb = new StringBuilder(path.substring(0, i));
}
continue;
}
if (sb != null) {
sb.append(path.charAt(i));
}
} finally {
prev = curr;
}
}
return sb != null ? sb.toString() : path;
}
/** @see Referenced code for path validation fix in https://github.com/mpgn/CVE-2019-3799 **/
private String cleanLeadingSlash(String path) {
boolean slash = false;
for (int i = 0; i < path.length(); i++) {
if (path.charAt(i) == '/') {
slash = true;
}
else if (path.charAt(i) > ' ' && path.charAt(i) != 127) {
if (i == 0 || (i == 1 && slash)) {
return path;
}
return (slash ? "/" + path.substring(i) : path.substring(i));
}
}
return (slash ? "/" : "");
}
/**
* Identifies invalid resource paths. By default rejects:
* <ul>
* <li>Paths that contain "WEB-INF" or "META-INF"
* <li>Paths that contain "../" after a call to
* {@link org.springframework.util.StringUtils#cleanPath}.
* <li>Paths that represent a {@link org.springframework.util.ResourceUtils#isUrl
* valid URL} or would represent one after the leading slash is removed.
* </ul>
* <p><strong>Note:</strong> this method assumes that leading, duplicate '/'
* or control characters (e.g. white space) have been trimmed so that the
* path starts predictably with a single '/' or does not have one.
* @param path the path to validate
* @return {@code true} if the path is invalid, {@code false} otherwise
* @since 3.0.6
* @see Referenced code for path validation fix in https://github.com/mpgn/CVE-2019-3799
*/
protected boolean isInvalidPath(String path) {
if (path.contains("WEB-INF") || path.contains("META-INF")) {
return true;
}
if (path.contains(":/")) {
String relativePath = (path.charAt(0) == '/' ? path.substring(1) : path);
if (ResourceUtils.isUrl(relativePath) || relativePath.startsWith("url:")) {
return true;
}
}
if (path.contains("..") && StringUtils.cleanPath(path).contains("../")) {
return true;
}
return false;
}
}