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

tests/dynamic_fixtures/xxe/go/benign.go

@@ -0,0 +1,25 @@
+// Phase 05 (Track J.3) — Go XXE benign fixture.
+//
+// Same parser surface as `vuln.go` but `Strict` is left at the
+// default `true`, so the doctype is rejected and no entity body is
+// substituted.
+package benign
+
+import (
+	"bytes"
+	"encoding/xml"
+)
+
+type Data struct {
+	XMLName xml.Name `xml:"data"`
+	Value   string   `xml:",chardata"`
+}
+
+func Run(body string) (*Data, error) {
+	d := xml.NewDecoder(bytes.NewReader([]byte(body)))
+	out := &Data{}
+	if err := d.Decode(out); err != nil {
+		return nil, err
+	}
+	return out, nil
+}

tests/dynamic_fixtures/xxe/go/vuln.go

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+// Phase 05 (Track J.3) — Go XXE vuln fixture.
+//
+// The function builds an `encoding/xml.Decoder` against the attacker
+// payload with `Strict: false` so the doctype is parsed and any
+// `<!ENTITY xxe SYSTEM "file:///…">` in the payload is resolved and
+// substituted into element values.
+package vuln
+
+import (
+	"bytes"
+	"encoding/xml"
+)
+
+type Data struct {
+	XMLName xml.Name `xml:"data"`
+	Value   string   `xml:",chardata"`
+}
+
+func Run(body string) (*Data, error) {
+	d := xml.NewDecoder(bytes.NewReader([]byte(body)))
+	d.Strict = false
+	out := &Data{}
+	if err := d.Decode(out); err != nil {
+		return nil, err
+	}
+	return out, nil
+}

tests/dynamic_fixtures/xxe/java/benign.java

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+// Phase 05 (Track J.3) — Java XXE benign fixture.
+//
+// Same parser surface as `vuln.java` but the factory is hardened with
+// `disallow-doctype-decl`, so the same payload's `<!ENTITY>` block is
+// rejected at parse time and no entity body is substituted.
+import java.io.ByteArrayInputStream;
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import org.w3c.dom.Document;
+
+public class Benign {
+    public static Document run(byte[] payload) throws Exception {
+        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+        factory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
+        DocumentBuilder builder = factory.newDocumentBuilder();
+        return builder.parse(new ByteArrayInputStream(payload));
+    }
+}

tests/dynamic_fixtures/xxe/java/vuln.java

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+// Phase 05 (Track J.3) — Java XXE vuln fixture.
+//
+// The function feeds attacker bytes to a stock `DocumentBuilderFactory`
+// without setting `disallow-doctype-decl` / `XMLConstants.FEATURE_
+// SECURE_PROCESSING`, so any `<!ENTITY xxe SYSTEM "file:///…">`
+// declaration in the payload is resolved and its body substituted
+// into the parsed tree.
+import java.io.ByteArrayInputStream;
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import org.w3c.dom.Document;
+
+public class Vuln {
+    public static Document run(byte[] payload) throws Exception {
+        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
+        DocumentBuilder builder = factory.newDocumentBuilder();
+        return builder.parse(new ByteArrayInputStream(payload));
+    }
+}

tests/dynamic_fixtures/xxe/php/benign.php

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+<?php
+// Phase 05 (Track J.3) — PHP XXE benign fixture.
+//
+// Same parser surface as `vuln.php` but the entity loader stays
+// disabled and the LIBXML_NOENT flag is omitted, so the same payload's
+// `<!ENTITY>` block is rejected and no entity body is substituted.
+function run(string $body) {
+    libxml_disable_entity_loader(true);
+    return simplexml_load_string($body);
+}

tests/dynamic_fixtures/xxe/php/vuln.php

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+<?php
+// Phase 05 (Track J.3) — PHP XXE vuln fixture.
+//
+// The function pulls XML off the request and feeds it to
+// `simplexml_load_string` after re-enabling the libxml entity loader
+// — so any `<!ENTITY xxe SYSTEM "file:///…">` in the payload is
+// resolved and its body substituted into the parsed document.
+function run(string $body) {
+    libxml_disable_entity_loader(false);
+    return simplexml_load_string($body, "SimpleXMLElement", LIBXML_NOENT);
+}

tests/dynamic_fixtures/xxe/python/benign.py

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+"""Phase 05 (Track J.3) — Python XXE benign fixture.
+
+Same parser surface as `vuln.py` but the parser is configured with
+`resolve_entities=False` and `no_network=True`, so the same payload's
+`<!ENTITY>` block is rejected and no entity body is substituted.
+"""
+from lxml import etree
+
+
+def run(body: bytes):
+    parser = etree.XMLParser(resolve_entities=False, no_network=True)
+    return etree.fromstring(body, parser=parser)

tests/dynamic_fixtures/xxe/python/vuln.py

@@ -0,0 +1,13 @@
+"""Phase 05 (Track J.3) — Python XXE vuln fixture.
+
+The function pulls XML bytes off the request and feeds them straight
+to `lxml.etree.XMLParser(resolve_entities=True)`, so any
+`<!ENTITY xxe SYSTEM "file:///…">` in the payload is resolved and its
+body substituted into the parsed tree.
+"""
+from lxml import etree
+
+
+def run(body: bytes):
+    parser = etree.XMLParser(resolve_entities=True)
+    return etree.fromstring(body, parser=parser)

tests/dynamic_fixtures/xxe/ruby/benign.rb

@@ -0,0 +1,11 @@
+# Phase 05 (Track J.3) — Ruby XXE benign fixture.
+#
+# Same parser surface as `vuln.rb` but the document is built under
+# `REXML::Document::entity_expansion_limit = 0`, so the same payload's
+# `<!ENTITY>` block triggers no expansion.
+require 'rexml/document'
+
+def run(body)
+  REXML::Document.entity_expansion_limit = 0
+  REXML::Document.new(body)
+end

tests/dynamic_fixtures/xxe/ruby/vuln.rb

@@ -0,0 +1,11 @@
+# Phase 05 (Track J.3) — Ruby XXE vuln fixture.
+#
+# The function feeds attacker XML straight to `REXML::Document.new`
+# without disabling entity expansion, so any `<!ENTITY xxe SYSTEM
+# "file:///…">` in the payload is resolved and its body substituted
+# into the parsed document.
+require 'rexml/document'
+
+def run(body)
+  REXML::Document.new(body)
+end

tests/xxe_corpus.rs

@@ -0,0 +1,294 @@
+//! Phase 05 (Track J.3) — XXE corpus acceptance.
+//!
+//! Asserts the new cap end-to-end: corpus slices register per-engine
+//! vuln/benign pairs for Java / Python / PHP / Ruby / Go, the
+//! lang-aware resolver pairs them inside the correct slice, the
+//! per-language harness emitters splice in the synthetic XML parser +
+//! entity-expansion probe + sink-hit sentinel, and the framework
+//! adapters fire on the canonical sink call.
+//!
+//! `cargo nextest run --features dynamic --test xxe_corpus`.
+
+#![cfg(feature = "dynamic")]
+
+use nyx_scanner::dynamic::corpus::{
+    audit_marker_collisions, benign_payload_for_lang, payloads_for_lang,
+    resolve_benign_control_lang, Oracle,
+};
+use nyx_scanner::dynamic::framework::registry::adapters_for;
+use nyx_scanner::dynamic::lang;
+use nyx_scanner::dynamic::oracle::ProbePredicate;
+use nyx_scanner::dynamic::probe::ProbeKind;
+use nyx_scanner::dynamic::spec::{EntryKind, HarnessSpec, PayloadSlot};
+use nyx_scanner::labels::Cap;
+use nyx_scanner::summary::FuncSummary;
+use nyx_scanner::symbol::Lang;
+
+const LANGS: &[Lang] = &[Lang::Java, Lang::Python, Lang::Php, Lang::Ruby, Lang::Go];
+
+fn make_spec(lang: Lang, entry_file: &str, entry_name: &str) -> HarnessSpec {
+    HarnessSpec {
+        finding_id: "phase05test0001".into(),
+        entry_file: entry_file.into(),
+        entry_name: entry_name.into(),
+        entry_kind: EntryKind::Function,
+        lang,
+        toolchain_id: "phase05".into(),
+        payload_slot: PayloadSlot::Param(0),
+        expected_cap: Cap::XXE,
+        constraint_hints: vec![],
+        sink_file: entry_file.into(),
+        sink_line: 1,
+        spec_hash: "phase05test0001".into(),
+        derivation: nyx_scanner::dynamic::spec::SpecDerivationStrategy::FromFlowSteps,
+        stubs_required: vec![],
+        framework: None,
+    }
+}
+
+#[test]
+fn corpus_registers_xxe_for_every_supported_lang() {
+    for lang in LANGS {
+        let slice = payloads_for_lang(Cap::XXE, *lang);
+        assert!(!slice.is_empty(), "XXE has no payloads for {lang:?}");
+        let has_vuln = slice.iter().any(|p| !p.is_benign);
+        let has_benign = slice.iter().any(|p| p.is_benign);
+        assert!(has_vuln, "{lang:?} XXE missing vuln payload");
+        assert!(has_benign, "{lang:?} XXE missing benign control");
+    }
+}
+
+#[test]
+fn xxe_unsupported_caps_unchanged_for_other_langs() {
+    // Phase 05 only fills Java / Python / PHP / Ruby / Go — Rust / C
+    // / Cpp / JS / TS stay empty.
+    for lang in [
+        Lang::Rust,
+        Lang::C,
+        Lang::Cpp,
+        Lang::JavaScript,
+        Lang::TypeScript,
+    ] {
+        assert!(
+            payloads_for_lang(Cap::XXE, lang).is_empty(),
+            "unexpected XXE payloads registered for {lang:?}",
+        );
+    }
+}
+
+#[test]
+fn benign_control_resolves_within_lang_slice() {
+    for lang in LANGS {
+        let slice = payloads_for_lang(Cap::XXE, *lang);
+        let vuln = slice.iter().find(|p| !p.is_benign).unwrap();
+        let resolved =
+            resolve_benign_control_lang(vuln, Cap::XXE, *lang).expect("paired control");
+        assert!(resolved.is_benign);
+        let direct = benign_payload_for_lang(Cap::XXE, *lang).unwrap();
+        assert_eq!(direct.label, resolved.label);
+    }
+}
+
+#[test]
+fn payload_oracle_carries_xxe_entity_expanded_predicate() {
+    for lang in LANGS {
+        let slice = payloads_for_lang(Cap::XXE, *lang);
+        let vuln = slice.iter().find(|p| !p.is_benign).unwrap();
+        match &vuln.oracle {
+            Oracle::SinkProbe { predicates } => {
+                assert!(
+                    predicates.iter().any(|p| matches!(
+                        p,
+                        ProbePredicate::XxeEntityExpanded { require_expanded: true }
+                    )),
+                    "{lang:?} vuln payload missing XxeEntityExpanded{{require_expanded:true}}",
+                );
+            }
+            other => panic!("expected SinkProbe oracle for {lang:?}, got {other:?}"),
+        }
+    }
+}
+
+#[test]
+fn vuln_payload_bytes_contain_doctype_entity_declaration() {
+    // The whole differential rule rests on the vuln payload carrying
+    // an `<!ENTITY … SYSTEM "…">` decl and the benign control NOT
+    // carrying one — pin both invariants so a future corpus tweak
+    // does not silently break the oracle.
+    for lang in LANGS {
+        let slice = payloads_for_lang(Cap::XXE, *lang);
+        let vuln = slice.iter().find(|p| !p.is_benign).unwrap();
+        let benign = slice.iter().find(|p| p.is_benign).unwrap();
+        let vuln_text = std::str::from_utf8(vuln.bytes).unwrap();
+        let benign_text = std::str::from_utf8(benign.bytes).unwrap();
+        assert!(
+            vuln_text.contains("<!ENTITY") && vuln_text.contains("SYSTEM"),
+            "{lang:?} vuln payload must declare a SYSTEM entity",
+        );
+        assert!(
+            !benign_text.contains("<!ENTITY"),
+            "{lang:?} benign control must not declare an entity",
+        );
+    }
+}
+
+#[test]
+fn marker_collisions_clean_with_phase_05_additions() {
+    assert!(audit_marker_collisions().is_empty());
+}
+
+#[test]
+fn probe_kind_xxe_serdes() {
+    let original = ProbeKind::Xxe {
+        entity_expanded: true,
+    };
+    let json = serde_json::to_string(&original).unwrap();
+    assert!(json.contains("Xxe"));
+    assert!(json.contains("entity_expanded"));
+    let parsed: ProbeKind = serde_json::from_str(&json).unwrap();
+    assert_eq!(parsed, original);
+}
+
+#[test]
+fn lang_emitter_dispatches_to_xxe_harness() {
+    // Per-lang `sink_callee_marker` pins which parser-construction
+    // string the harness names in its probe record — the
+    // `DocumentBuilder.parse` / `lxml.etree.XMLParser` /
+    // `simplexml_load_string` / `REXML::Document.new` /
+    // `xml.Decoder.Decode` boundary the brief calls out.
+    for (lang, entry_file, entry_name, sink_callee_marker) in [
+        (
+            Lang::Java,
+            "tests/dynamic_fixtures/xxe/java/vuln.java",
+            "run",
+            "DocumentBuilder.parse",
+        ),
+        (
+            Lang::Python,
+            "tests/dynamic_fixtures/xxe/python/vuln.py",
+            "run",
+            "lxml.etree.XMLParser.parse",
+        ),
+        (
+            Lang::Php,
+            "tests/dynamic_fixtures/xxe/php/vuln.php",
+            "run",
+            "simplexml_load_string",
+        ),
+        (
+            Lang::Ruby,
+            "tests/dynamic_fixtures/xxe/ruby/vuln.rb",
+            "run",
+            "REXML::Document.new",
+        ),
+        (
+            Lang::Go,
+            "tests/dynamic_fixtures/xxe/go/vuln.go",
+            "Run",
+            "xml.Decoder.Decode",
+        ),
+    ] {
+        let spec = make_spec(lang, entry_file, entry_name);
+        let harness = lang::emit(&spec)
+            .unwrap_or_else(|e| panic!("emit failed for {lang:?}: {e:?}"));
+        assert!(
+            harness.source.contains("entity_expanded"),
+            "{lang:?} xxe harness must carry the entity_expanded probe field",
+        );
+        assert!(
+            harness.source.contains(sink_callee_marker),
+            "{lang:?} xxe harness must name {sink_callee_marker:?} as the parser sink callee",
+        );
+        assert!(
+            harness.source.contains("__NYX_SINK_HIT__"),
+            "{lang:?} xxe harness must emit the sink-hit sentinel",
+        );
+        assert!(
+            harness.source.contains("<!ENTITY") || harness.source.contains("ENTITY"),
+            "{lang:?} xxe harness must include the entity-detection scanner",
+        );
+    }
+}
+
+#[test]
+fn framework_adapters_detect_xxe_sink() {
+    // Each lang registers its J.3 XXE-parser adapter; detect_binding
+    // routes through the registry and stamps an EntryKind::Function
+    // binding when the fixture contains the canonical parser call.
+    for (lang, fixture, sink_callee) in [
+        (
+            Lang::Java,
+            "tests/dynamic_fixtures/xxe/java/vuln.java",
+            "parse",
+        ),
+        (
+            Lang::Python,
+            "tests/dynamic_fixtures/xxe/python/vuln.py",
+            "fromstring",
+        ),
+        (
+            Lang::Php,
+            "tests/dynamic_fixtures/xxe/php/vuln.php",
+            "simplexml_load_string",
+        ),
+        (
+            Lang::Ruby,
+            "tests/dynamic_fixtures/xxe/ruby/vuln.rb",
+            "new",
+        ),
+        (
+            Lang::Go,
+            "tests/dynamic_fixtures/xxe/go/vuln.go",
+            "NewDecoder",
+        ),
+    ] {
+        let bytes = std::fs::read(fixture).expect("fixture exists");
+        let ts_lang = ts_language_for(lang);
+        let mut parser = tree_sitter::Parser::new();
+        parser.set_language(&ts_lang).unwrap();
+        let tree = parser.parse(&bytes, None).unwrap();
+        let mut summary = FuncSummary {
+            name: "run".into(),
+            file_path: fixture.to_owned(),
+            lang: slug(lang).into(),
+            ..Default::default()
+        };
+        summary
+            .callees
+            .push(nyx_scanner::summary::CalleeSite::bare(sink_callee));
+        let registry_slice = adapters_for(lang);
+        assert!(!registry_slice.is_empty(), "{lang:?} adapter slice empty");
+        let binding = nyx_scanner::dynamic::framework::detect_binding(
+            &summary,
+            tree.root_node(),
+            &bytes,
+            lang,
+        );
+        let b = binding
+            .unwrap_or_else(|| panic!("{lang:?} adapter must detect the XXE fixture"));
+        assert_eq!(b.kind, EntryKind::Function);
+        assert!(!b.adapter.is_empty());
+    }
+}
+
+fn ts_language_for(lang: Lang) -> tree_sitter::Language {
+    match lang {
+        Lang::Java => tree_sitter::Language::from(tree_sitter_java::LANGUAGE),
+        Lang::Python => tree_sitter::Language::from(tree_sitter_python::LANGUAGE),
+        Lang::Php => tree_sitter::Language::from(tree_sitter_php::LANGUAGE_PHP),
+        Lang::Ruby => tree_sitter::Language::from(tree_sitter_ruby::LANGUAGE),
+        Lang::Go => tree_sitter::Language::from(tree_sitter_go::LANGUAGE),
+        other => panic!("unsupported test lang {other:?}"),
+    }
+}
+
+fn slug(lang: Lang) -> &'static str {
+    match lang {
+        Lang::Java => "java",
+        Lang::Python => "python",
+        Lang::Php => "php",
+        Lang::Ruby => "ruby",
+        Lang::Go => "go",
+        _ => "other",
+    }
+}