[pitboss] phase 05: Track J.3 + Track L.3 — XXE corpus + DocumentBuilder / lxml / libxml / SimpleXML adapters

src/dynamic/framework/adapters/xxe_java.rs

@@ -0,0 +1,139 @@
+//! Java [`super::super::FrameworkAdapter`] matching XXE-prone XML parser
+//! constructions.
+//!
+//! Phase 05 (Track J.3).  Fires when the function body invokes a
+//! `DocumentBuilder.parse` / `SAXParser.parse` / `XMLInputFactory`
+//! call site and the surrounding source pulls in one of the
+//! `javax.xml.parsers` / `org.w3c.dom` / `org.xml.sax` packages —
+//! i.e. an XML parser that, by default and without
+//! `disallow-doctype-decl`, expands external entities.
+
+use crate::dynamic::framework::{FrameworkAdapter, FrameworkBinding};
+use crate::evidence::EntryKind;
+use crate::summary::FuncSummary;
+use crate::symbol::Lang;
+
+pub struct XxeJavaAdapter;
+
+const ADAPTER_NAME: &str = "xxe-java";
+
+fn callee_is_xml_parse(name: &str) -> bool {
+    let last = name.rsplit_once('.').map(|(_, s)| s).unwrap_or(name);
+    matches!(
+        last,
+        "parse"
+            | "newDocumentBuilder"
+            | "newSAXParser"
+            | "createXMLEventReader"
+            | "createXMLStreamReader"
+            | "newInstance"
+    )
+}
+
+fn source_imports_xml_parser(file_bytes: &[u8]) -> bool {
+    const NEEDLES: &[&[u8]] = &[
+        b"javax.xml.parsers",
+        b"DocumentBuilderFactory",
+        b"DocumentBuilder",
+        b"SAXParserFactory",
+        b"XMLInputFactory",
+        b"org.xml.sax",
+        b"org.w3c.dom",
+    ];
+    NEEDLES
+        .iter()
+        .any(|n| file_bytes.windows(n.len()).any(|w| w == *n))
+}
+
+impl FrameworkAdapter for XxeJavaAdapter {
+    fn name(&self) -> &'static str {
+        ADAPTER_NAME
+    }
+
+    fn lang(&self) -> Lang {
+        Lang::Java
+    }
+
+    fn detect(
+        &self,
+        summary: &FuncSummary,
+        _ast: tree_sitter::Node<'_>,
+        file_bytes: &[u8],
+    ) -> Option<FrameworkBinding> {
+        let matches_call = super::any_callee_matches(summary, callee_is_xml_parse);
+        let matches_source = source_imports_xml_parser(file_bytes);
+        if matches_call && matches_source {
+            return Some(FrameworkBinding {
+                adapter: ADAPTER_NAME.to_owned(),
+                kind: EntryKind::Function,
+                route: None,
+                request_params: Vec::new(),
+                response_writer: None,
+                middleware: Vec::new(),
+            });
+        }
+        // Fall-back: source clearly imports the XXE-prone parser even
+        // when the call-graph summary did not capture the parse call.
+        if matches_source
+            && file_bytes
+                .windows(b".parse(".len())
+                .any(|w| w == b".parse(")
+        {
+            return Some(FrameworkBinding {
+                adapter: ADAPTER_NAME.to_owned(),
+                kind: EntryKind::Function,
+                route: None,
+                request_params: Vec::new(),
+                response_writer: None,
+                middleware: Vec::new(),
+            });
+        }
+        None
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn parse_java(src: &[u8]) -> tree_sitter::Tree {
+        let mut parser = tree_sitter::Parser::new();
+        let lang = tree_sitter::Language::from(tree_sitter_java::LANGUAGE);
+        parser.set_language(&lang).unwrap();
+        parser.parse(src, None).unwrap()
+    }
+
+    #[test]
+    fn fires_on_document_builder_parse() {
+        let src: &[u8] = b"import javax.xml.parsers.DocumentBuilderFactory;\n\
+            public class V {\n  public static void run(byte[] b) throws Exception {\n\
+                DocumentBuilderFactory f = DocumentBuilderFactory.newInstance();\n\
+                f.newDocumentBuilder().parse(new java.io.ByteArrayInputStream(b));\n\
+            }\n}\n";
+        let tree = parse_java(src);
+        let summary = FuncSummary {
+            name: "run".into(),
+            callees: vec![crate::summary::CalleeSite::bare("parse")],
+            ..Default::default()
+        };
+        let binding = XxeJavaAdapter
+            .detect(&summary, tree.root_node(), src)
+            .expect("must fire on DocumentBuilder.parse fixture");
+        assert_eq!(binding.adapter, ADAPTER_NAME);
+        assert_eq!(binding.kind, EntryKind::Function);
+    }
+
+    #[test]
+    fn skips_plain_function() {
+        let src: &[u8] =
+            b"public class V { public static void run(String b) { System.out.println(b); } }\n";
+        let tree = parse_java(src);
+        let summary = FuncSummary {
+            name: "run".into(),
+            ..Default::default()
+        };
+        assert!(XxeJavaAdapter
+            .detect(&summary, tree.root_node(), src)
+            .is_none());
+    }
+}