Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Add detection for Recursion in Java #14

Open
wants to merge 10 commits into
base: main
Choose a base branch
from
Open
Show file tree
Hide file tree
Changes from 3 commits
Commits
File filter

Filter by extension

Filter by extension


Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
3 changes: 2 additions & 1 deletion .codeqlmanifest.json
Original file line number Diff line number Diff line change
@@ -1,6 +1,7 @@
{
"provide": [
"cpp/*/qlpack.yml",
"go/*/qlpack.yml"
"go/*/qlpack.yml",
"java/*/qlpack.yml"
]
}
1 change: 1 addition & 0 deletions .github/workflows/test.yml
Original file line number Diff line number Diff line change
Expand Up @@ -16,3 +16,4 @@ jobs:
run: |
${{ steps.init.outputs.codeql-path }} test run ./cpp/test/
${{ steps.init.outputs.codeql-path }} test run ./go/test/
${{ steps.init.outputs.codeql-path }} test run ./java/test/
12 changes: 11 additions & 1 deletion README.md
Original file line number Diff line number Diff line change
Expand Up @@ -66,6 +66,14 @@ codeql database analyze database.db --format=sarif-latest --output=./tob.sarif -
|[Missing MinVersion in tls.Config](./go/src/docs/security/MissingMinVersionTLS/MissingMinVersionTLS.md)|This rule finds cases when you do not set the `tls.Config.MinVersion` explicitly for servers. By default version 1.0 is used, which is considered insecure. This rule does not mark explicitly set insecure versions|error|medium|
|[Trim functions misuse](./go/src/docs/security/TrimMisuse/TrimMisuse.md)|Finds calls to `string.{Trim,TrimLeft,TrimRight}` with the 2nd argument not being a cutset but a continuous substring to be trimmed|error|low|

### Java-kotlin

#### Security

| Name | Description | Severity | Precision |
| --- | ----------- | :----: | :--------: |
|[Recursive functions](./java-kotlin/src/docs/security/Recursion/Recursion.md)|Detects recursive calls|warning|low|

## Query suites

CodeQL queries are grouped into "suites". To execute queries from a specific suit add its name after a colon: `trailofbits/cpp-queries:codeql-suites/tob-cpp-full.qls`.
Expand All @@ -89,7 +97,7 @@ echo "--search-path '$PWD/codeql-queries'" > "${HOME}/.config/codeql/config"

Check that CodeQL CLI detects the new qlpacks:
```sh
codeql resolve qlpacks | grep trailofbits
codeql resolve packs | grep trailofbits
```

#### Before committing
Expand All @@ -99,6 +107,7 @@ Run tests:
cd codeql-queries
codeql test run ./cpp/test
codeql test run ./go/test
codeql test run ./java/test
```

Update dependencies:
Expand All @@ -115,4 +124,5 @@ Generate markdown query help files
```sh
codeql generate query-help ./cpp/src/ --format=markdown --output ./cpp/src/docs
codeql generate query-help ./go/src/ --format=markdown --output ./go/src/docs
codeql generate query-help ./java/src/ --format=markdown --output ./java/src/docs
```
28 changes: 28 additions & 0 deletions java/src/codeql-pack.lock.yml
Original file line number Diff line number Diff line change
@@ -0,0 +1,28 @@
---
lockVersion: 1.0.0
dependencies:
codeql/dataflow:
version: 1.1.5
codeql/java-all:
version: 4.2.0
codeql/mad:
version: 1.0.11
codeql/rangeanalysis:
version: 1.0.11
codeql/regex:
version: 1.0.11
codeql/ssa:
version: 1.0.11
codeql/threat-models:
version: 1.0.11
codeql/tutorial:
version: 1.0.11
codeql/typeflow:
version: 1.0.11
codeql/typetracking:
version: 1.0.11
codeql/util:
version: 1.0.11
codeql/xml:
version: 1.0.11
compiled: false
5 changes: 5 additions & 0 deletions java/src/codeql-suites/tob-java-code-scanning.qls
Original file line number Diff line number Diff line change
@@ -0,0 +1,5 @@
- description: Security queries for Java
- queries: 'security'
from: trailofbits/java-queries
- exclude:
tags contain: experimental
3 changes: 3 additions & 0 deletions java/src/codeql-suites/tob-java-full.qls
Original file line number Diff line number Diff line change
@@ -0,0 +1,3 @@
- description: Queries for Java
- queries: '.'
from: trailofbits/java-queries
39 changes: 39 additions & 0 deletions java/src/docs/security/Recursion/Recursion.md
Original file line number Diff line number Diff line change
@@ -0,0 +1,39 @@
# Recursive functions
Recursive functions are methods that call themselves either directly or indirectly through other functions. While recursion can be a powerful programming technique, unbounded recursion on user inputs can lead to stack overflow errors and program crashes, potentially enabling denial of service attacks. This query detects recursive patterns up to order 4.


## Recommendation
Review recursive functions and ensure that they are either: - Not processing user-controlled data - The data has been properly sanitized before recursing - The recursion has an explicit depth limit

Consider replacing recursion with iterative alternatives where possible.


## Example

```java
// From https://github.com/x-stream/xstream/blob/dfa1d35462fe84412ee72a9b0cf5b5c633086520/xstream/src/java/com/thoughtworks/xstream/io/binary/BinaryStreamReader.java#L165
private Token readToken() {
// ...
try {
final Token token = tokenFormatter.read(in);
switch (token.getType()) {
case Token.TYPE_MAP_ID_TO_VALUE: // 0x2
idRegistry.put(token.getId(), token.getValue());
return readToken(); // Next one please.
default:
return token;
}
} catch (final IOException e) {
throw new StreamException(e);
}
// ...
}
```
In this example, a binary stream reader processes tokens recursively.

For each new token \`0x2\`, the parser will create a new recursive call. If this stream is user-controlled, an attacker can generate too many stackframes and crash the application with a `StackOverflow` error.


## References
* Trail Of Bits Blog: [Low-effort denial of service with recursion](https://blog.trailofbits.com/2024/05/16/TODO/)
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

TODO

* CWE-674: [Uncontrolled Recursion](https://cwe.mitre.org/data/definitions/674.html)
12 changes: 12 additions & 0 deletions java/src/qlpack.yml
Original file line number Diff line number Diff line change
@@ -0,0 +1,12 @@
---
name: trailofbits/java-queries
description: CodeQL queries for Java developed by Trail of Bits
authors: Trail of Bits
version: 0.0.1
license: AGPL
library: false
extractor: java-kotlin
dependencies:
codeql/java-all: "*"
suites: codeql-suites
defaultSuiteFile: codeql-suites/tob-java-code-scanning.qls
39 changes: 39 additions & 0 deletions java/src/security/Recursion/Recursion.qhelp
Original file line number Diff line number Diff line change
@@ -0,0 +1,39 @@
<!DOCTYPE qhelp SYSTEM "qhelp.dtd">
<qhelp>
<overview>
<p>
Recursive functions are methods that call themselves either directly or indirectly through other functions.
While recursion can be a powerful programming technique, unbounded recursion on user inputs can lead
to stack overflow errors and program crashes, potentially enabling denial of service attacks.

This query detects recursive patterns up to order 4.
</p>

</overview>
<recommendation>
<p>
Review recursive functions and ensure that they are either:
- Not processing user-controlled data
- The data has been properly sanitized before recursing
- The recursion has an explicit depth limit
</p>
<p>
Consider replacing recursion with iterative alternatives where possible.
</p>
</recommendation>
<example>
<sample src="RecursiveCall.java" />
<p>In this example, a binary stream reader processes tokens recursively.</p>
<p>For each new token `0x2`, the parser will create a new recursive call.
If this stream is user-controlled, an attacker can generate too many stackframes
and crash the application with a <code>StackOverflow</code> error.</p>
</example>
<references>
<li>
Trail Of Bits Blog: <a href="https://blog.trailofbits.com/2024/05/16/TODO/">Low-effort denial of service with recursion</a>
Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

TODO

</li>
<li>
CWE-674: <a href="https://cwe.mitre.org/data/definitions/674.html">Uncontrolled Recursion</a>
</li>
</references>
</qhelp>
37 changes: 37 additions & 0 deletions java/src/security/Recursion/Recursion.ql
Original file line number Diff line number Diff line change
@@ -0,0 +1,37 @@
/**
* @name Recursive functions
* @id tob/java/unbounded-recursion
* @description Detects possibly unbounded recursive calls
* @kind problem
* @tags security
* @precision low
* @problem.severity warning
* @security-severity 3.0
* @group security
*/

import java

predicate isTestPackage(RefType referenceType) {
referenceType.getPackage().getName().toLowerCase().matches("%test%") or
referenceType.getPackage().getName().toLowerCase().matches("%benchmark%") or
referenceType.getName().toLowerCase().matches("%test%")
}

class RecursiveMethod extends Method {
RecursiveMethod() {
exists(Method m | this.calls+(m) and this = m)
}
}

/**
* TODO ideas:
* - limit results to methods that take any user input
* - check if recursive calls are bounded (takes argument that is decremented for every call)
* - do not return methods that have calls to self (or unbounded recursion) that are conditional
* - gather and print whole call graph (list of calls from recursiveMethod to itself)
*/
from RecursiveMethod recursiveMethod
where
not isTestPackage(recursiveMethod.getDeclaringType())
select recursiveMethod, "Method $@ has unbounded, possibly infinite recursive calls", recursiveMethod, recursiveMethod.toString()
17 changes: 17 additions & 0 deletions java/src/security/Recursion/RecursiveCall.java
Original file line number Diff line number Diff line change
@@ -0,0 +1,17 @@
// From https://github.com/x-stream/xstream/blob/dfa1d35462fe84412ee72a9b0cf5b5c633086520/xstream/src/java/com/thoughtworks/xstream/io/binary/BinaryStreamReader.java#L165
private Token readToken() {
// ...
try {
final Token token = tokenFormatter.read(in);
switch (token.getType()) {
case Token.TYPE_MAP_ID_TO_VALUE: // 0x2
idRegistry.put(token.getId(), token.getValue());
return readToken(); // Next one please.
default:
return token;
}
} catch (final IOException e) {
throw new StreamException(e);
}
// ...
}
28 changes: 28 additions & 0 deletions java/test/codeql-pack.lock.yml
Original file line number Diff line number Diff line change
@@ -0,0 +1,28 @@
---
lockVersion: 1.0.0
dependencies:
codeql/dataflow:
version: 1.1.5
codeql/java-all:
version: 4.2.0
codeql/mad:
version: 1.0.11
codeql/rangeanalysis:
version: 1.0.11
codeql/regex:
version: 1.0.11
codeql/ssa:
version: 1.0.11
codeql/threat-models:
version: 1.0.11
codeql/tutorial:
version: 1.0.11
codeql/typeflow:
version: 1.0.11
codeql/typetracking:
version: 1.0.11
codeql/util:
version: 1.0.11
codeql/xml:
version: 1.0.11
compiled: false
8 changes: 8 additions & 0 deletions java/test/qlpack.yml
Original file line number Diff line number Diff line change
@@ -0,0 +1,8 @@
---
name: trailofbits/java-tests
authors: Trail of Bits
license: AGPL
extractor: java-kotlin
tests: .
dependencies:
trailofbits/java-queries: "*"
3 changes: 3 additions & 0 deletions java/test/query-tests/security/Recursion/Recursion.expected
Original file line number Diff line number Diff line change
@@ -0,0 +1,3 @@
| Recursion.java:8:16:8:20 | bar(...) | $@ | Recursion.java:8:16:8:20 | bar(...) | Recursion(2): bar(2) -> foo(7) -> bar |
| Recursion.java:12:16:12:32 | directRecursive(...) | $@ | Recursion.java:12:16:12:32 | directRecursive(...) | Recursion(1): directRecursive(11) -> directRecursive |
| Recursion.java:31:16:31:23 | level0(...) | $@ | Recursion.java:31:16:31:23 | level0(...) | Recursion(3): level0(15) -> level1(21) -> level2(27) -> level0 |
Loading
Loading