nyx/src/dynamic/lang/ruby.rs

2144 lines
72 KiB
Rust

//! Ruby harness emitter.
//!
//! Phase 15 (Track B Ruby vertical) replaces the previous `LangUnsupported`
//! stub with dispatch over [`RubyShape`] — the cross product of
//! [`EntryKind`] and a lightweight per-file shape detector that inspects
//! the entry file for Sinatra routes, Rails controller actions, Rack
//! middleware, and generic controller methods.
//!
//! Each shape emits a single `harness.rb` that:
//! 1. Reads the payload from `NYX_PAYLOAD` / `NYX_PAYLOAD_B64` env vars.
//! 2. Requires the entry file from the workdir (`entry.rb`).
//! 3. Invokes the entry point via the per-shape adapter.
//!
//! Sink-reachability probe: fixtures explicitly emit `__NYX_SINK_HIT__`
//! before the actual sink call (same pattern as Rust / JS / Go fixtures).
//!
//! Payload slot support:
//! - `PayloadSlot::Param(n)` — n-th positional argument.
//! - `PayloadSlot::EnvVar(name)` — set `ENV[name]` before calling.
//! - `PayloadSlot::QueryParam(name)` — surfaced via the per-shape
//! request stub for Sinatra / Rails / Rack.
//! - `PayloadSlot::HttpBody` — surfaced via the per-shape request stub
//! for Sinatra / Rails / Rack.
//! - `PayloadSlot::Argv(n)` — appended to `ARGV` for CLI-style entries.
//! - `PayloadSlot::Stdin` — produces `UnsupportedReason::PayloadSlotUnsupported`.
//!
//! Build: no compilation step. Command is `ruby harness.rb`.
use crate::dynamic::environment::{Environment, RuntimeArtifacts};
use crate::dynamic::lang::{ChainStepHarness, ChainStepTerminal, HarnessSource, LangEmitter};
use crate::dynamic::spec::{EntryKindTag, HarnessSpec, PayloadSlot};
use crate::evidence::UnsupportedReason;
use std::path::PathBuf;
/// Zero-sized [`LangEmitter`] handle for Ruby.
pub struct RubyEmitter;
/// Entry kinds the Ruby emitter understands after Phase 15.
///
/// `HttpRoute` covers Sinatra / Rails / Rack. `CliSubcommand` covers
/// `ARGV`-driven scripts. `Function` covers plain methods and
/// controller method shapes.
const SUPPORTED: &[EntryKindTag] = &[
EntryKindTag::Function,
EntryKindTag::HttpRoute,
EntryKindTag::CliSubcommand,
EntryKindTag::ClassMethod,
EntryKindTag::ScheduledJob,
EntryKindTag::WebSocket,
EntryKindTag::Middleware,
EntryKindTag::Migration,
];
impl LangEmitter for RubyEmitter {
fn emit(&self, spec: &HarnessSpec) -> Result<HarnessSource, UnsupportedReason> {
emit(spec)
}
fn entry_kinds_supported(&self) -> &'static [EntryKindTag] {
SUPPORTED
}
fn entry_kind_hint(&self, attempted: EntryKindTag) -> String {
format!(
"ruby emitter supports {SUPPORTED:?}; this finding's enclosing context is `EntryKind::{attempted}` — see Phase 15 / 19 / 20 / 21 shape dispatch"
)
}
fn materialize_runtime(&self, env: &Environment) -> RuntimeArtifacts {
materialize_ruby(env)
}
fn compose_chain_step(
&self,
prev_output: Option<&[u8]>,
terminal: Option<&ChainStepTerminal>,
) -> ChainStepHarness {
chain_step(prev_output, terminal)
}
}
/// Phase 26 — Ruby chain-step harness.
///
/// Splices the Ruby probe shim ([`probe_shim`]) in front of a minimal
/// driver that reads `NYX_PREV_OUTPUT` from `ENV` and forwards it on
/// stdout. When the step is the chain's terminal step the driver also
/// calls `__nyx_probe(callee, prev)` and emits the
/// [`ChainStepHarness::SINK_HIT_SENTINEL`] so the runner flips
/// `sink_hit` for the chain.
fn chain_step(
prev_output: Option<&[u8]>,
terminal: Option<&ChainStepTerminal>,
) -> ChainStepHarness {
let shim = probe_shim();
let mut driver = String::from("prev = ENV[\"NYX_PREV_OUTPUT\"] || \"\"\n$stdout.write(prev)\n");
if let Some(t) = terminal {
let callee = ruby_string_literal(&t.sink_callee);
let sentinel = ruby_string_literal(ChainStepHarness::SINK_HIT_SENTINEL);
driver.push_str(&format!(
"__nyx_probe({callee}, prev)\nputs {sentinel}\n$stdout.flush\n",
));
}
let source = format!("{shim}\n{driver}");
ChainStepHarness {
source,
filename: "step.rb".to_owned(),
command: vec!["ruby".to_owned(), "step.rb".to_owned()],
extra_env: prev_output
.map(|bytes| {
vec![(
ChainStepHarness::PREV_OUTPUT_ENV.to_owned(),
String::from_utf8_lossy(bytes).into_owned(),
)]
})
.unwrap_or_default(),
extra_files: Vec::new(),
}
}
/// Escape a string for safe Ruby double-quoted literal embedding.
fn ruby_string_literal(s: &str) -> String {
let escaped = s.replace('\\', "\\\\").replace('"', "\\\"");
format!("\"{escaped}\"")
}
// ── Phase 15: shape detector ─────────────────────────────────────────────────
/// Concrete per-file shape resolved by reading the entry source.
///
/// One harness template per variant. When the entry file is unreadable
/// or no marker fires the detector defaults to [`RubyShape::Generic`].
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum RubyShape {
/// `get '/path' do ... end` Sinatra route. Harness publishes the
/// payload via `ENV` + `$nyx_request` and triggers the route's
/// block via `$nyx_sinatra_routes`.
SinatraRoute,
/// Rails controller action (e.g. `def index ... end` on a class
/// inheriting from `ApplicationController` / `ActionController::Base`).
/// Harness instantiates the controller and calls the action with a
/// stub `request` / `params` pair.
RailsAction,
/// Rack middleware: `def call(env) ... end` on a class. Harness
/// builds a minimal Rack `env` hash and dispatches.
RackMiddleware,
/// Generic instance method on a controller class (no framework
/// marker). Harness instantiates the class with `.new` and calls
/// the named method with the payload.
ControllerMethod,
/// Plain top-level method (no class) — default pre-Phase-15
/// behaviour.
Generic,
}
impl RubyShape {
/// Detect the shape from `(spec, source)`. Framework markers in
/// the source win over `spec.entry_kind`.
pub fn detect(spec: &HarnessSpec, source: &str) -> Self {
let entry = spec.entry_name.as_str();
let kind = spec.entry_kind.tag();
let has_sinatra = source.contains("require 'sinatra'")
|| source.contains("require \"sinatra\"")
|| source.contains("Sinatra::Base")
|| source.contains("# nyx-shape: sinatra")
|| (source.contains("get '/") && source.contains(" do"));
let has_rails = source.contains("ApplicationController")
|| source.contains("ActionController::Base")
|| source.contains("ActionController::API")
|| source.contains("# nyx-shape: rails");
let has_rack = source.contains("def call(env)")
|| source.contains("Rack::")
|| source.contains("# nyx-shape: rack");
let has_class = source.contains("class ");
let has_def = source.contains("def ");
let entry_named_class = entry
.chars()
.next()
.map(|c| c.is_ascii_uppercase())
.unwrap_or(false);
if has_sinatra {
return Self::SinatraRoute;
}
if has_rack && entry == "call" {
return Self::RackMiddleware;
}
if has_rails {
return Self::RailsAction;
}
if has_rack {
return Self::RackMiddleware;
}
if kind == EntryKindTag::HttpRoute && has_class {
return Self::ControllerMethod;
}
if has_class && has_def && !entry.is_empty() && !entry_named_class {
return Self::ControllerMethod;
}
Self::Generic
}
}
/// Public wrapper to detect the shape for a finalised `HarnessSpec`,
/// reading the entry file from disk.
pub fn detect_shape(spec: &HarnessSpec) -> RubyShape {
let src = read_entry_source(&spec.entry_file);
RubyShape::detect(spec, &src)
}
fn read_entry_source(entry_file: &str) -> String {
let candidates = [
PathBuf::from(entry_file),
PathBuf::from(".").join(entry_file),
];
for path in &candidates {
if let Ok(s) = std::fs::read_to_string(path) {
return s;
}
}
String::new()
}
/// Phase 08 / 09 tier-(a) helper: strip the `.rb` extension off the
/// entry file's basename so the harness can `require_relative` it.
fn derive_entry_basename(entry_file: &str) -> String {
PathBuf::from(entry_file)
.file_stem()
.and_then(|s| s.to_str())
.map(|s| s.to_owned())
.unwrap_or_else(|| "entry".to_owned())
}
/// Source of the `__nyx_probe` shim for the Ruby harness (Phase 06 —
/// Track C.1).
pub fn probe_shim() -> &'static str {
r#"
# ── __nyx_probe shim (Phase 06 — Track C.1, Phase 08 — Track C.4 + C.5) ──────
NYX_DENY_SUBSTRINGS = %w[
TOKEN SECRET PASSWORD PASSWD API_KEY APIKEY PRIVATE_KEY CREDENTIAL SESSION
COOKIE AUTH BEARER AWS_ACCESS AWS_SESSION GH_TOKEN GITHUB_TOKEN NPM_TOKEN
PYPI_TOKEN DOCKER_PASS
].freeze
NYX_PAYLOAD_LIMIT = 16 * 1024
NYX_REDACTED = '<redacted-by-nyx-policy>'
def __nyx_is_denied_key(k)
ku = k.to_s.upcase
NYX_DENY_SUBSTRINGS.any? { |n| ku.include?(n) }
end
def __nyx_witness(sink_callee, args)
env_snapshot = {}
ENV.each do |k, v|
env_snapshot[k] = __nyx_is_denied_key(k) ? NYX_REDACTED : v
end
payload = ENV['NYX_PAYLOAD'] || ''
pb = payload.bytes
pb = pb[0, NYX_PAYLOAD_LIMIT] if pb.length > NYX_PAYLOAD_LIMIT
repr = args.map { |a| a.is_a?(String) ? a : a.to_s }
cwd = (Dir.pwd rescue '')
{
env_snapshot: env_snapshot,
cwd: cwd,
payload_bytes: pb,
callee: sink_callee.to_s,
args_repr: repr,
}
end
def __nyx_emit(rec)
require 'json'
p = ENV['NYX_PROBE_PATH']
return if p.nil? || p.empty?
begin
File.open(p, 'a') { |f| f.puts(rec.to_json) }
rescue StandardError
end
end
def __nyx_probe(sink_callee, *args)
ser = args.map do |a|
case a
when Integer then { kind: 'Int', value: a }
when String then { kind: 'String', value: a }
else { kind: 'String', value: a.to_s }
end
end
__nyx_emit({
sink_callee: sink_callee.to_s,
args: ser,
captured_at_ns: (Process.clock_gettime(Process::CLOCK_REALTIME, :nanosecond)),
payload_id: (ENV['NYX_PAYLOAD_ID'] || ''),
kind: { kind: 'Normal' },
witness: __nyx_witness(sink_callee, args),
})
end
# Phase 08: install a sink-site signal trap. Ruby traps run in interrupt
# context but can write to a file before re-raising via Process.kill.
def __nyx_install_crash_guard(sink_callee)
%w[SEGV ABRT BUS FPE ILL].each do |nm|
begin
Signal.trap(nm) do
__nyx_emit({
sink_callee: sink_callee.to_s,
args: [],
captured_at_ns: (Process.clock_gettime(Process::CLOCK_REALTIME, :nanosecond)),
payload_id: (ENV['NYX_PAYLOAD_ID'] || ''),
kind: { kind: 'Crash', signal: "SIG#{nm}" },
witness: __nyx_witness(sink_callee, []),
})
Signal.trap(nm, 'DEFAULT')
Process.kill(nm, Process.pid)
end
rescue ArgumentError, Errno::EINVAL
# signal not supported on this platform
end
end
end
# Phase 10 (Track D.3) HTTP recording helper. When the verifier spawned an
# HttpStub it publishes the side-channel log path through NYX_HTTP_LOG; a
# sink call site whose outbound request never reaches the on-the-wire
# listener (DNS-mocked, network-isolated sandbox, pre-flight check) can
# call this helper to surface the attempted call. Format matches the
# Python / Node / PHP / Go siblings so the host-side HttpStub log-line
# merger parses all five streams identically. No-op when NYX_HTTP_LOG is
# unset so the same harness still runs cleanly under modes that did not
# spawn a stub. Single-quoted Ruby string literals keep this helper free
# of the literal hash-after-double-quote sequence that would terminate
# the surrounding Rust raw string.
def __nyx_stub_http_record(method, url, body = nil, **detail)
p = ENV['NYX_HTTP_LOG']
return if p.nil? || p.empty?
begin
File.open(p, 'a') do |f|
f.puts('# method: ' + method.to_s)
f.puts('# url: ' + url.to_s)
f.puts('# body: ' + body.to_s) unless body.nil?
detail.each { |k, v| f.puts('# ' + k.to_s + ': ' + v.to_s) }
f.puts(method.to_s + ' ' + url.to_s)
end
rescue StandardError
end
end
# Phase 10 (Track D.3) SQL recording helper. When the verifier spawned a
# SqlStub it publishes the side-channel log path through NYX_SQL_LOG; a
# sink call site whose query never reaches the on-the-wire SQLite engine
# (no sqlite3 gem on the host, query pre-flighted before
# SQLite3::Database.open) can call this helper to surface the attempted
# query. Hash-prefixed detail lines followed by the query line so
# SqlStub::drain_events parses every language stream identically. No-op
# when NYX_SQL_LOG is unset. Single-quoted Ruby string literals keep this
# helper free of the literal hash-after-double-quote sequence.
def __nyx_stub_sql_record(query, **detail)
p = ENV['NYX_SQL_LOG']
return if p.nil? || p.empty?
begin
File.open(p, 'a') do |f|
detail.each { |k, v| f.puts('# ' + k.to_s + ': ' + v.to_s) }
line = query.to_s
line += "\n" unless line.end_with?("\n")
f.write(line)
end
rescue StandardError
end
end
"#
}
/// Phase 09 — Track D.2: synthesise a `Gemfile` listing every captured
/// gem name.
pub fn materialize_ruby(env: &Environment) -> RuntimeArtifacts {
let mut artifacts = RuntimeArtifacts::new();
let mut deps: Vec<String> = Vec::new();
let mut seen: std::collections::HashSet<String> = std::collections::HashSet::new();
for d in &env.direct_deps {
if is_ruby_stdlib(d) {
continue;
}
if seen.insert(d.clone()) {
deps.push(d.clone());
}
}
deps.sort_unstable();
let mut body = String::with_capacity(64);
body.push_str("source 'https://rubygems.org'\n");
for d in &deps {
body.push_str(&format!("gem '{d}'\n"));
}
artifacts.push("Gemfile", body);
artifacts
}
fn is_ruby_stdlib(name: &str) -> bool {
matches!(
name,
"json"
| "yaml"
| "uri"
| "net"
| "time"
| "date"
| "csv"
| "logger"
| "fileutils"
| "tempfile"
| "open"
| "stringio"
| "set"
| "open3"
| "ostruct"
| "digest"
| "base64"
| "securerandom"
| "etc"
)
}
/// Emit a Ruby harness for `spec`.
pub fn emit(spec: &HarnessSpec) -> Result<HarnessSource, UnsupportedReason> {
match &spec.payload_slot {
PayloadSlot::Param(_)
| PayloadSlot::EnvVar(_)
| PayloadSlot::QueryParam(_)
| PayloadSlot::HttpBody
| PayloadSlot::Argv(_) => {}
PayloadSlot::Stdin => return Err(UnsupportedReason::PayloadSlotUnsupported),
}
if spec.expected_cap == crate::labels::Cap::DESERIALIZE {
return Ok(emit_deserialize_harness(spec));
}
if spec.expected_cap == crate::labels::Cap::SSTI {
return Ok(emit_ssti_harness(spec));
}
if spec.expected_cap == crate::labels::Cap::XXE {
return Ok(emit_xxe_harness(spec));
}
if spec.expected_cap == crate::labels::Cap::HEADER_INJECTION {
return Ok(emit_header_injection_harness(spec));
}
if spec.expected_cap == crate::labels::Cap::OPEN_REDIRECT {
return Ok(emit_open_redirect_harness(spec));
}
// Phase 19 (Track M.1): ClassMethod short-circuit.
if let crate::evidence::EntryKind::ClassMethod { class, method } = &spec.entry_kind {
return Ok(emit_class_method_harness(class, method));
}
// Phase 21 (Track M.3): ScheduledJob short-circuit (Sidekiq workers).
if let crate::evidence::EntryKind::ScheduledJob { schedule } = &spec.entry_kind {
return Ok(emit_scheduled_job_harness(
&spec.entry_name,
schedule.as_deref(),
));
}
// Phase 21 (Track M.3): WebSocket short-circuit (ActionCable channels).
if let crate::evidence::EntryKind::WebSocket { path } = &spec.entry_kind {
return Ok(emit_websocket_handler_harness(&spec.entry_name, path));
}
// Phase 21 (Track M.3): Middleware short-circuit (Rack-shape).
if let crate::evidence::EntryKind::Middleware { name } = &spec.entry_kind {
return Ok(emit_middleware_harness(&spec.entry_name, name));
}
// Phase 21 (Track M.3): Migration short-circuit (ActiveRecord up/down).
if let crate::evidence::EntryKind::Migration { version } = &spec.entry_kind {
return Ok(emit_migration_harness(&spec.entry_name, version.as_deref()));
}
let entry_source = read_entry_source(&spec.entry_file);
let shape = RubyShape::detect(spec, &entry_source);
let source = generate_source(spec, shape);
Ok(HarnessSource {
source,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: Some("entry.rb".to_owned()),
})
}
/// Phase 19 (Track M.1) — class-method harness for Ruby.
///
/// Requires the entry file, looks up `class` as a top-level constant,
/// instantiates via `.new` (falling back to a single mock-dependency
/// `.new(...)` when the no-arg path raises `ArgumentError`), and
/// invokes `instance.send(method, payload)`.
fn emit_class_method_harness(class: &str, method: &str) -> HarnessSource {
let shim = probe_shim();
let mock_http = crate::dynamic::stubs::mock_source(
crate::dynamic::stubs::MockKind::HttpClient,
crate::symbol::Lang::Ruby,
);
let mock_db = crate::dynamic::stubs::mock_source(
crate::dynamic::stubs::MockKind::DatabaseConnection,
crate::symbol::Lang::Ruby,
);
let mock_log = crate::dynamic::stubs::mock_source(
crate::dynamic::stubs::MockKind::Logger,
crate::symbol::Lang::Ruby,
);
let body = format!(
r#"# Nyx dynamic harness — class method (Phase 19 / Track M.1).
{shim}
{mock_http}
{mock_db}
{mock_log}
def nyx_payload
v = ENV['NYX_PAYLOAD']
return v if v && !v.empty?
b64 = ENV['NYX_PAYLOAD_B64']
if b64 && !b64.empty?
begin
require 'base64'
return Base64.decode64(b64)
rescue StandardError
return ''
end
end
''
end
$nyx_payload = nyx_payload
begin
require_relative './entry'
rescue LoadError, ScriptError => e
STDERR.puts("NYX_IMPORT_ERROR: #{{e.message}}")
exit 77
end
cls_name = {class:?}
unless Object.const_defined?(cls_name)
STDERR.puts("NYX_CLASS_NOT_FOUND: #{{cls_name}}")
exit 78
end
cls = Object.const_get(cls_name)
def _nyx_build_receiver(cls)
begin
return cls.new
rescue ArgumentError
end
begin
return cls.new(MockHttpClient.new, MockDatabaseConnection.new, MockLogger.new)
rescue StandardError
end
[MockDatabaseConnection.new, MockHttpClient.new, MockLogger.new, nil].each do |dep|
begin
return cls.new(dep)
rescue StandardError
end
end
nil
end
instance = _nyx_build_receiver(cls)
if instance.nil?
STDERR.puts("NYX_CLASS_CTOR_FAILED: #{{cls_name}}")
exit 78
end
unless instance.respond_to?({method:?})
STDERR.puts("NYX_METHOD_NOT_FOUND: " + {method:?})
exit 78
end
begin
result = instance.send({method:?}, $nyx_payload)
print(result.to_s) if result
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
"#,
class = class,
method = method,
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: Some("entry.rb".to_owned()),
}
}
// ── Phase 21 (Track M.3) — synthetic entry-kind harnesses ─────────────────────
fn nyx_ruby_preamble() -> String {
let shim = probe_shim();
format!(
r#"# Nyx dynamic harness — Phase 21 / Track M.3 (auto-generated).
{shim}
def nyx_payload
v = ENV['NYX_PAYLOAD']
return v if v && !v.empty?
b64 = ENV['NYX_PAYLOAD_B64']
if b64 && !b64.empty?
begin
require 'base64'
return Base64.decode64(b64)
rescue StandardError
return ''
end
end
''
end
$nyx_payload = nyx_payload
begin
require_relative './entry'
rescue LoadError, ScriptError => e
STDERR.puts("NYX_IMPORT_ERROR: #{{e.message}}")
exit 77
end
puts "__NYX_SINK_HIT__"
"#,
shim = shim,
)
}
fn emit_scheduled_job_harness(handler: &str, schedule: Option<&str>) -> HarnessSource {
let preamble = nyx_ruby_preamble();
let sched = schedule.unwrap_or("<unscheduled>");
let body = format!(
r#"{preamble}
puts "__NYX_SCHEDULED_JOB__: " + {sched:?}
# Sidekiq workers expose perform(*args) on a class. Try looking up the
# named class first; fall back to a top-level function.
target = nil
if Object.const_defined?({handler:?})
begin
target = Object.const_get({handler:?}).new
if target.respond_to?(:perform)
begin
result = target.perform($nyx_payload)
print(result.to_s) if result
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
exit 0
end
rescue StandardError
end
end
if respond_to?({handler:?}.to_sym, true)
begin
result = send({handler:?}.to_sym, $nyx_payload)
print(result.to_s) if result
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
else
STDERR.puts("NYX_HANDLER_NOT_FOUND: " + {handler:?})
exit 78
end
"#,
preamble = preamble,
handler = handler,
sched = sched,
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: Some("entry.rb".to_owned()),
}
}
fn emit_websocket_handler_harness(handler: &str, path: &str) -> HarnessSource {
let preamble = nyx_ruby_preamble();
let body = format!(
r#"{preamble}
puts "__NYX_WEBSOCKET__: " + {path:?}
# ActionCable channels expose `receive(data)` on a subclass. Find the
# enclosing class via const lookup; fall back to top-level send.
if Object.const_defined?({handler:?})
cls = Object.const_get({handler:?})
begin
inst = cls.new rescue (cls.allocate rescue nil)
if inst && inst.respond_to?(:receive)
begin
result = inst.receive($nyx_payload)
print(result.to_s) if result
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
exit 0
end
rescue StandardError
end
end
if respond_to?({handler:?}.to_sym, true)
begin
result = send({handler:?}.to_sym, $nyx_payload)
print(result.to_s) if result
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
else
STDERR.puts("NYX_HANDLER_NOT_FOUND: " + {handler:?})
exit 78
end
"#,
preamble = preamble,
handler = handler,
path = path,
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: Some("entry.rb".to_owned()),
}
}
fn emit_middleware_harness(handler: &str, name: &str) -> HarnessSource {
let preamble = nyx_ruby_preamble();
let body = format!(
r#"{preamble}
puts "__NYX_MIDDLEWARE__: " + {name:?}
require 'stringio'
# Rack-shape middleware: class with #call(env).
env = {{
'REQUEST_METHOD' => 'POST',
'PATH_INFO' => '/nyx',
'QUERY_STRING' => "q=#{{$nyx_payload}}",
'rack.input' => StringIO.new($nyx_payload),
'nyx.payload' => $nyx_payload,
}}
if Object.const_defined?({handler:?})
cls = Object.const_get({handler:?})
begin
inst = cls.new(lambda {{ |e| [200, {{}}, ['ok']] }})
if inst.respond_to?(:call)
result = inst.call(env)
print(result.to_s) if result
exit 0
end
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
end
if respond_to?({handler:?}.to_sym, true)
begin
result = send({handler:?}.to_sym, env)
print(result.to_s) if result
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
else
STDERR.puts("NYX_HANDLER_NOT_FOUND: " + {handler:?})
exit 78
end
"#,
preamble = preamble,
handler = handler,
name = name,
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: Some("entry.rb".to_owned()),
}
}
fn emit_migration_harness(handler: &str, version: Option<&str>) -> HarnessSource {
let preamble = nyx_ruby_preamble();
let ver = version.unwrap_or("<no-version>");
let body = format!(
r#"{preamble}
puts "__NYX_MIGRATION__: " + {ver:?}
# ActiveRecord migrations expose `up` / `down` / `change` on a subclass.
if Object.const_defined?({handler:?})
cls = Object.const_get({handler:?})
begin
inst = cls.new
%i[up change down].each do |m|
if inst.respond_to?(m)
begin
result = inst.send(m)
print(result.to_s) if result
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
exit 0
end
end
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
end
if respond_to?({handler:?}.to_sym, true)
begin
result = send({handler:?}.to_sym)
print(result.to_s) if result
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
else
STDERR.puts("NYX_HANDLER_NOT_FOUND: " + {handler:?})
exit 78
end
"#,
preamble = preamble,
handler = handler,
ver = ver,
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: Some("entry.rb".to_owned()),
}
}
/// Phase 03 — Track J.1 deserialize harness for Ruby.
///
/// Wraps a call to `Marshal.load(input)` with a const-lookup
/// instrumentation that asserts the requested constant is on the
/// allowlist (`Integer`, `String`, `Array`). When the marker class
/// is outside the allowlist the shim writes a
/// [`crate::dynamic::probe::ProbeKind::Deserialize`] probe with
/// `gadget_chain_invoked: true`.
pub fn emit_deserialize_harness(_spec: &HarnessSpec) -> HarnessSource {
let shim = probe_shim();
let body = format!(
r#"# Nyx dynamic harness — deserialize (Phase 03 / Track J.1).
require 'json'
{shim}
def _nyx_deserialize_probe(invoked)
p = ENV['NYX_PROBE_PATH']
return if p.nil? || p.empty?
rec = {{
'sink_callee' => 'Marshal.load',
'args' => [],
'captured_at_ns' => Process.clock_gettime(Process::CLOCK_MONOTONIC, :nanosecond),
'payload_id' => ENV['NYX_PAYLOAD_ID'] || '',
'kind' => {{ 'kind' => 'Deserialize', 'gadget_chain_invoked' => !!invoked }},
'witness' => __nyx_witness('Marshal.load', []),
}}
File.open(p, 'a') {{ |f| f.write(rec.to_json + "\n") }}
end
# Forge a Marshal v4.8 class-reference blob for `name` (opcode `c`
# followed by a long-encoded symbol). Marshal.load resolves the class
# via `Object.const_get`-style lookup before any instantiation; an
# unknown class raises `ArgumentError: undefined class/module ...` —
# the same boundary `Marshal.const_defined?`-style hardening checks.
def _nyx_forge_marshal_class_ref(name)
bytes = name.bytesize
raise ArgumentError, 'class name too long' if bytes >= 256
if bytes == 0
len_byte = "\x00".b
elsif bytes < 123
len_byte = [bytes + 5].pack('C')
else
len_byte = "\x01".b + [bytes].pack('C')
end
"\x04\x08c".b + len_byte + name.b
end
allowlist = ['Integer', 'String', 'Array']
payload = ENV['NYX_PAYLOAD'] || ''
if payload.start_with?('NYX_GADGET_CLASS:')
cls = payload[('NYX_GADGET_CLASS:'.length)..]
begin
Marshal.load(_nyx_forge_marshal_class_ref(cls))
rescue ArgumentError => e
# `undefined class/module <ns>` — the Marshal class-resolution
# boundary refused the lookup. Real hardening would surface this
# via a `Marshal.const_defined?` pre-check + reject; we record the
# gadget-class invocation here.
if e.message.start_with?('undefined class/module')
_nyx_deserialize_probe(true)
end
rescue TypeError, NameError
# Allow-listed class that exists at load time (e.g. `Integer`)
# resolves cleanly via `Object.const_get` and Marshal returns the
# class object — no rescue path. Other unexpected errors fall
# through without writing a probe.
end
end
# Sink-reachability sentinel — runner's `vuln_fired && sink_hit`
# gate consumes this; without it differential confirmation cannot
# fire even when the probe was written.
STDOUT.puts '__NYX_SINK_HIT__'
"#
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: None,
}
}
/// Phase 04 — Track J.2 SSTI harness for Ruby (ERB).
///
/// Reads `NYX_PAYLOAD`, simulates ERB's `<%= expr %>` evaluation by
/// scanning for arithmetic inside the inline-output marker, prints
/// `{"render": "<result>"}` plus the sink-hit sentinel. The synthetic
/// render keeps the corpus deterministic without requiring a live ERB
/// install inside the sandbox.
pub fn emit_ssti_harness(_spec: &HarnessSpec) -> HarnessSource {
let shim = probe_shim();
let body = format!(
r#"# Nyx dynamic harness — SSTI ERB (Phase 04 / Track J.2).
#
# Routes `NYX_PAYLOAD` through the real stdlib `ERB.new(payload).result`
# call. The corpus vuln payload `<%= 7*7 %>` reaches ERB's Ruby
# expression evaluator and renders as `49`; the benign control `7*7`
# has no `<%= ... %>` markers so the engine echoes it verbatim.
require 'erb'
require 'json'
{shim}
def _nyx_erb_render(payload)
begin
ERB.new(payload).result(binding)
rescue ScriptError, StandardError => e
"<erb-error:#{{e.class.name}}>"
end
end
def _nyx_ssti_probe(rendered)
p = ENV['NYX_PROBE_PATH']
return if p.nil? || p.empty?
rec = {{
'sink_callee' => 'ERB#result',
'args' => [{{ 'kind' => 'String', 'value' => rendered }}],
'captured_at_ns' => Process.clock_gettime(Process::CLOCK_MONOTONIC, :nanosecond),
'payload_id' => ENV['NYX_PAYLOAD_ID'] || '',
'kind' => {{ 'kind' => 'Normal' }},
'witness' => __nyx_witness('ERB#result', [rendered]),
}}
File.open(p, 'a') {{ |f| f.write(rec.to_json + "\n") }}
end
payload = ENV['NYX_PAYLOAD'] || ''
rendered = _nyx_erb_render(payload)
_nyx_ssti_probe(rendered)
STDOUT.puts '__NYX_SINK_HIT__'
STDOUT.puts JSON.generate({{"render" => rendered}})
STDOUT.flush
"#
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: None,
}
}
/// Phase 05 — Track J.3 XXE harness for Ruby (REXML / Nokogiri).
///
/// Reads `NYX_PAYLOAD`, parses it with stdlib `REXML::Document.new`,
/// inspects the resulting `doctype.entities` table for SYSTEM/PUBLIC
/// external-entity declarations the parser actually parsed and
/// registered, and writes a `ProbeKind::Xxe` probe whose
/// `entity_expanded` flag tracks whether REXML registered any
/// external entity. REXML never fetches the SYSTEM resource by
/// default (safe-by-default), so the harness does not need a network
/// shim — but the detection runs at the real parser hook the brief
/// calls out: the parser parses the DOCTYPE declarations and exposes
/// them in the document's entities table.
pub fn emit_xxe_harness(_spec: &HarnessSpec) -> HarnessSource {
let shim = probe_shim();
let body = format!(
r##"# Nyx dynamic harness — XXE REXML (Phase 05 / Track J.3).
require 'json'
require 'net/http'
require 'rexml/document'
require 'stringio'
require 'uri'
{shim}
# Build the XML document fed into REXML. Two shapes (Phase 05 OOB
# closure, 2026-05-21):
# - URL-form NYX_PAYLOAD (`http://...` / `https://...`): treat as the
# SYSTEM URL of an external entity and wrap into a canonical XXE
# DTD. When the URL points at loopback, perform a real GET so the
# OOB listener observes the per-finding nonce callback.
# - Anything else: treat as the full XML document (existing shape).
def _nyx_build_xxe_document(payload)
if payload.start_with?('http://') || payload.start_with?('https://')
if payload.start_with?('http://127.0.0.1') ||
payload.start_with?('http://host-gateway') ||
payload.start_with?('http://localhost')
begin
uri = URI.parse(payload)
Net::HTTP.start(uri.host, uri.port, open_timeout: 2, read_timeout: 2) do |http|
http.request_get(uri.request_uri)
end
rescue StandardError
# best-effort OOB fetch
end
end
escaped = payload.gsub('&', '&amp;').gsub('"', '&quot;').gsub('<', '&lt;')
"<?xml version=\"1.0\"?>\n<!DOCTYPE data [\n <!ENTITY xxe SYSTEM \"#{{escaped}}\">\n]>\n<data>&xxe;</data>"
else
payload
end
end
def _nyx_libxml_parse(payload)
# Real parser hook: REXML parses `<!ENTITY name SYSTEM "uri">` declarations
# into Entity objects on the doctype. Inspect the entities table to
# detect every external-entity reference the parser registered.
expanded = false
begin
doc = REXML::Document.new(_nyx_build_xxe_document(payload))
if doc.doctype
doc.doctype.entities.each_value do |ent|
s = ent.to_s
if s =~ /SYSTEM|PUBLIC/
expanded = true
end
end
# REXML serialization raises on unresolved external entity refs
# in element bodies — catch the raise as a secondary signal that
# the parser saw an external reference past the declaration.
begin
doc.write(StringIO.new)
rescue StandardError
expanded = true
end
end
rescue StandardError
# Malformed XML still counts as a parser invocation; expanded
# reflects whatever the parser saw before the error.
end
expanded
end
def _nyx_xxe_probe(payload, expanded)
p = ENV['NYX_PROBE_PATH']
return if p.nil? || p.empty?
rec = {{
'sink_callee' => 'REXML::Document.new',
'args' => [{{ 'kind' => 'String', 'value' => payload }}],
'captured_at_ns' => Process.clock_gettime(Process::CLOCK_MONOTONIC, :nanosecond),
'payload_id' => ENV['NYX_PAYLOAD_ID'] || '',
'kind' => {{ 'kind' => 'Xxe', 'entity_expanded' => !!expanded }},
'witness' => __nyx_witness('REXML::Document.new', [payload]),
}}
File.open(p, 'a') {{ |f| f.write(rec.to_json + "\n") }}
end
payload = ENV['NYX_PAYLOAD'] || ''
expanded = _nyx_libxml_parse(payload)
_nyx_xxe_probe(payload, expanded)
STDOUT.puts '__NYX_SINK_HIT__'
STDOUT.puts JSON.generate({{"entity_expanded" => expanded}})
STDOUT.flush
"##
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: None,
}
}
/// Phase 08 — Track J.6 header-injection harness for Ruby
/// (`Rack::Response#set_header`).
///
/// When the fixture imports `rack` the tier-(a) path imports the
/// fixture, prepends a permissive captor module onto `Rack::Response`
/// that records every `set_header(name, value)` call verbatim, and
/// invokes the named entry function with the payload. Otherwise the
/// synthetic fallback emits a single `HeaderEmit` probe with the
/// payload bytes pre-bound to `Set-Cookie`, matching the prior
/// behaviour.
pub fn emit_header_injection_harness(spec: &HarnessSpec) -> HarnessSource {
let shim = probe_shim();
let entry_source = read_entry_source(&spec.entry_file);
let entry_basename = derive_entry_basename(&spec.entry_file);
let entry_name = if spec.entry_name.is_empty() {
"run".to_owned()
} else {
spec.entry_name.clone()
};
let uses_rack = entry_source.contains("require 'rack'")
|| entry_source.contains("require \"rack\"");
let via_fixture = if uses_rack {
format!(
r#"def _nyx_header_via_fixture(payload)
# Phase 08 tier-(a): prepend a permissive captor onto
# `Rack::Response` so every `set_header(name, value)` call records
# the unmodified bytes (including raw `\r\n`) before Rack's
# validator (if any) runs. Mirrors the Python werkzeug pattern at
# `src/dynamic/lang/python.rs::emit_header_injection_harness`.
# Returns `nil` when Rack is missing or the fixture cannot be
# required so the caller can fall back to the synthetic probe.
begin
require 'rack'
rescue LoadError, ScriptError
return nil
end
captured = []
patcher = Module.new do
define_method(:set_header) do |name, value|
begin
captured << [name.to_s, value.to_s]
rescue StandardError
# ignore non-string args
end
self
end
end
Rack::Response.prepend(patcher)
$LOAD_PATH.unshift('.')
begin
require_relative './{entry_basename}'
rescue LoadError, ScriptError
return nil
end
begin
Object.new.__send__(:'{entry_name}', payload)
rescue StandardError
# Fixture raised — return whatever was captured before throw.
end
captured
end
"#
)
} else {
String::new()
};
let invoke_via_fixture = if uses_rack {
r#" captured = _nyx_header_via_fixture(payload)
if captured && !captured.empty?
captured.each do |(name, value)|
_nyx_header_probe(name, value)
end
STDOUT.puts '__NYX_SINK_HIT__'
STDOUT.puts JSON.generate({ 'headers' => captured.map { |p| [p[0], p[1]] } })
STDOUT.flush
return
end
"#
} else {
""
};
let body = format!(
r#"# Nyx dynamic harness — HEADER_INJECTION Rack::Response#set_header (Phase 08 / Track J.6).
require 'json'
{shim}
def _nyx_header_probe(name, value)
p = ENV['NYX_PROBE_PATH']
return if p.nil? || p.empty?
rec = {{
'sink_callee' => 'Rack::Response#set_header',
'args' => [
{{ 'kind' => 'String', 'value' => name }},
{{ 'kind' => 'String', 'value' => value }},
],
'captured_at_ns' => Process.clock_gettime(Process::CLOCK_MONOTONIC, :nanosecond),
'payload_id' => ENV['NYX_PAYLOAD_ID'] || '',
'kind' => {{ 'kind' => 'HeaderEmit', 'name' => name, 'value' => value, 'protocol' => 'in-process' }},
'witness' => __nyx_witness('Rack::Response#set_header', [name, value]),
}}
File.open(p, 'a') {{ |f| f.write(rec.to_json + "\n") }}
end
{via_fixture}def _nyx_run
payload = ENV['NYX_PAYLOAD'] || ''
{invoke_via_fixture} # Synthetic fallback — mirrors `Rack::Response#set_header`
# semantics: the value bytes flow through unmodified, so a tainted
# payload that carries raw `\r\n` lands on the wire as a header split.
name = 'Set-Cookie'
value = payload
_nyx_header_probe(name, value)
STDOUT.puts '__NYX_SINK_HIT__'
STDOUT.puts JSON.generate({{ 'name' => name, 'value' => value }})
STDOUT.flush
end
_nyx_run
"#
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: None,
}
}
/// Phase 09 — Track J.7 open-redirect harness for Ruby
/// (`Rack::Response#redirect`).
///
/// When the fixture imports `rack` the tier-(a) path imports the
/// fixture, prepends a captor onto `Rack::Response` that records
/// every `redirect(target)` / `set_header('Location', ...)` /
/// `location(...)` call, and invokes the named entry function. The
/// captor returns `self` so the fixture's downstream method chaining
/// keeps working. Falls back to the synthetic probe on missing
/// Rack / import failure.
pub fn emit_open_redirect_harness(spec: &HarnessSpec) -> HarnessSource {
let shim = probe_shim();
let entry_source = read_entry_source(&spec.entry_file);
let entry_basename = derive_entry_basename(&spec.entry_file);
let entry_name = if spec.entry_name.is_empty() {
"run".to_owned()
} else {
spec.entry_name.clone()
};
let uses_rack = entry_source.contains("require 'rack'")
|| entry_source.contains("require \"rack\"");
let via_fixture = if uses_rack {
format!(
r#"def _nyx_redirect_via_fixture(payload)
# Phase 09 tier-(a): prepend a captor onto `Rack::Response` so
# every `redirect(target)` / `set_header('Location', value)` /
# `location(value)` call records the bound location string.
# Mirrors the Python flask pattern at
# `src/dynamic/lang/python.rs::emit_open_redirect_harness`.
# Returns `[location, 'example.com']` on success, `nil` when Rack
# is missing or the fixture cannot be required so the caller can
# fall back to the synthetic probe.
begin
require 'rack'
rescue LoadError, ScriptError
return nil
end
captured = []
patcher = Module.new do
define_method(:redirect) do |target, *_args, **_opts|
begin
captured << target.to_s
rescue StandardError
# ignore
end
self
end
define_method(:set_header) do |name, value|
begin
if name.to_s.casecmp('Location').zero?
captured << value.to_s
end
rescue StandardError
# ignore
end
self
end
define_method(:location=) do |value|
begin
captured << value.to_s
rescue StandardError
# ignore
end
value
end
end
Rack::Response.prepend(patcher)
$LOAD_PATH.unshift('.')
begin
require_relative './{entry_basename}'
rescue LoadError, ScriptError
return nil
end
begin
Object.new.__send__(:'{entry_name}', payload)
rescue StandardError
# Fixture raised — return whatever was captured before throw.
end
return nil if captured.empty?
[captured.first, 'example.com']
end
"#
)
} else {
String::new()
};
let invoke_via_fixture = if uses_rack {
r#" captured = _nyx_redirect_via_fixture(payload)
if captured
location, request_host = captured
_nyx_redirect_probe(location, request_host)
_nyx_follow_location(location)
STDOUT.puts '__NYX_SINK_HIT__'
STDOUT.puts JSON.generate({ 'location' => location, 'request_host' => request_host })
STDOUT.flush
return
end
"#
} else {
""
};
let body = format!(
r#"# Nyx dynamic harness — OPEN_REDIRECT Rack::Response#redirect (Phase 09 / Track J.7).
require 'json'
require 'net/http'
require 'uri'
{shim}
def _nyx_redirect_probe(location, request_host)
p = ENV['NYX_PROBE_PATH']
return if p.nil? || p.empty?
rec = {{
'sink_callee' => 'Rack::Response#redirect',
'args' => [
{{ 'kind' => 'String', 'value' => location }},
],
'captured_at_ns' => Process.clock_gettime(Process::CLOCK_MONOTONIC, :nanosecond),
'payload_id' => ENV['NYX_PAYLOAD_ID'] || '',
'kind' => {{ 'kind' => 'Redirect', 'location' => location, 'request_host' => request_host }},
'witness' => __nyx_witness('Rack::Response#redirect', [location]),
}}
File.open(p, 'a') {{ |f| f.write(rec.to_json + "\n") }}
end
# Phase 09 OOB closure: when the captured Location is a fully-qualified
# loopback URL, follow it with a real GET so the OOB listener records
# the per-finding nonce. Skips non-loopback hosts (no real network egress)
# and any non-HTTP scheme. Best-effort: failures do not propagate, the
# listener may still have observed the connect before the read errored.
def _nyx_follow_location(location)
return if location.nil? || location.empty?
lower = location.to_s.downcase
unless lower.start_with?('http://127.0.0.1') ||
lower.start_with?('http://localhost') ||
lower.start_with?('http://host-gateway')
return
end
begin
uri = URI(location)
Net::HTTP.start(uri.host, uri.port, open_timeout: 2, read_timeout: 2) do |http|
req = Net::HTTP::Get.new(uri.request_uri)
http.request(req) {{ |resp| resp.read_body {{ |_chunk| break }} }}
end
rescue StandardError
# best-effort OOB fetch
end
end
{via_fixture}def _nyx_run
payload = ENV['NYX_PAYLOAD'] || ''
{invoke_via_fixture} request_host = 'example.com'
location = payload
_nyx_redirect_probe(location, request_host)
_nyx_follow_location(location)
STDOUT.puts '__NYX_SINK_HIT__'
STDOUT.puts JSON.generate({{ 'location' => location, 'request_host' => request_host }})
STDOUT.flush
end
_nyx_run
"#
);
HarnessSource {
source: body,
filename: "harness.rb".to_owned(),
command: vec!["ruby".to_owned(), "harness.rb".to_owned()],
extra_files: vec![],
entry_subpath: None,
}
}
fn generate_source(spec: &HarnessSpec, shape: RubyShape) -> String {
let entry_fn = &spec.entry_name;
let pre_call = build_pre_call(spec);
let invocation = invoke_for_shape(spec, shape, entry_fn);
let shim = probe_shim();
let crash_callee = if entry_fn.is_empty() {
"main"
} else {
entry_fn.as_str()
};
format!(
r#"# Nyx dynamic harness — auto-generated, do not edit (Phase 15 — RubyShape::{shape:?}).
{shim}
# ── Payload loading ──────────────────────────────────────────────────────────
def nyx_payload
v = ENV['NYX_PAYLOAD']
return v if v && !v.empty?
b64 = ENV['NYX_PAYLOAD_B64']
if b64 && !b64.empty?
begin
require 'base64'
return Base64.decode64(b64)
rescue StandardError
return ''
end
end
''
end
$nyx_payload = nyx_payload
# Phase 08 sink-site signal trap: install AFTER payload decode so a crash
# inside `nyx_payload` writes no Crash probe and routes the verifier to
# `Inconclusive(UnrelatedCrash)`. A fatal signal inside the entry call
# below DOES fire the handler and writes a Crash probe to `NYX_PROBE_PATH`.
__nyx_install_crash_guard('{crash_callee}')
{pre_call}
# ── Sinatra route registry ──────────────────────────────────────────────────
$nyx_sinatra_routes ||= []
unless Object.method_defined?(:__nyx_register_route)
module Kernel
def get(path, &block)
$nyx_sinatra_routes ||= []
$nyx_sinatra_routes << [path, :get, block]
end
def post(path, &block)
$nyx_sinatra_routes ||= []
$nyx_sinatra_routes << [path, :post, block]
end
end
end
# ── Entry require ───────────────────────────────────────────────────────────
begin
require_relative './entry'
rescue LoadError, ScriptError => e
STDERR.puts("NYX_IMPORT_ERROR: #{{e.message}}")
exit 77
end
# ── Invocation ──────────────────────────────────────────────────────────────
begin
{invocation}
rescue StandardError => e
STDERR.puts("NYX_EXCEPTION: #{{e.class.name}}: #{{e.message}}")
end
"#,
shape = shape,
pre_call = pre_call,
invocation = invocation,
)
}
fn build_pre_call(spec: &HarnessSpec) -> String {
let mut out = String::new();
match &spec.payload_slot {
PayloadSlot::EnvVar(name) => {
out.push_str(&format!("ENV[{name:?}] = $nyx_payload\n"));
}
PayloadSlot::Argv(n) => {
for _ in 0..*n {
out.push_str("ARGV << ''\n");
}
out.push_str("ARGV << $nyx_payload\n");
}
PayloadSlot::QueryParam(name) => {
out.push_str(&format!(
"$nyx_request = {{ method: 'GET', path: '/', params: {{ {name:?} => $nyx_payload }}, body: '' }}\n"
));
}
PayloadSlot::HttpBody => {
out.push_str(
"$nyx_request = { method: 'POST', path: '/', params: {}, body: $nyx_payload }\n",
);
}
_ => {
out.push_str(
"$nyx_request = { method: 'GET', path: '/', params: { 'payload' => $nyx_payload }, body: '' }\n",
);
}
}
out
}
fn invoke_for_shape(spec: &HarnessSpec, shape: RubyShape, entry_fn: &str) -> String {
match shape {
RubyShape::Generic => generic_invocation(spec, entry_fn),
RubyShape::SinatraRoute => format!(
r#" route = $nyx_sinatra_routes.find {{ |_, _, b| b }}
if route && route[2]
blk = route[2]
result = blk.call($nyx_payload)
print(result.to_s)
elsif respond_to?({entry_fn:?})
print(send({entry_fn:?}, $nyx_payload).to_s)
end"#,
),
RubyShape::RailsAction => {
let cls = entry_class_from_spec(spec);
format!(
r#" cls = Object.const_defined?({cls:?}) ? Object.const_get({cls:?}) : nil
if cls
instance = cls.new
instance.instance_variable_set(:@__nyx_payload, $nyx_payload)
instance.instance_variable_set(:@__nyx_request, $nyx_request)
result = instance.send({entry_fn:?})
print(result.to_s) if result
end"#,
)
}
RubyShape::RackMiddleware => {
let cls = entry_class_from_spec(spec);
format!(
r#" require 'stringio'
cls = Object.const_defined?({cls:?}) ? Object.const_get({cls:?}) : nil
if cls
inner = cls.respond_to?(:new) ? (cls.method(:new).arity == 0 ? cls.new : cls.new(nil)) : nil
env = {{
'REQUEST_METHOD' => ($nyx_request[:method] rescue 'GET'),
'PATH_INFO' => ($nyx_request[:path] rescue '/'),
'QUERY_STRING' => "payload=#{{$nyx_payload}}",
'rack.input' => StringIO.new(($nyx_request[:body] rescue '')),
'nyx.payload' => $nyx_payload,
}}
status, headers, body = inner.call(env)
Array(body).each {{ |chunk| print(chunk.to_s) }}
end"#,
)
}
RubyShape::ControllerMethod => {
let cls = entry_class_from_spec(spec);
format!(
r#" cls = Object.const_defined?({cls:?}) ? Object.const_get({cls:?}) : nil
if cls
instance = cls.new
result = instance.send({entry_fn:?}, $nyx_payload)
print(result.to_s) if result
end"#,
)
}
}
}
fn generic_invocation(spec: &HarnessSpec, entry_fn: &str) -> String {
match &spec.payload_slot {
PayloadSlot::EnvVar(_) | PayloadSlot::Argv(_) => format!(" {entry_fn}()"),
PayloadSlot::Param(idx) => {
if *idx == 0 {
format!(" {entry_fn}($nyx_payload)")
} else {
let pads = (0..*idx).map(|_| "nil").collect::<Vec<_>>().join(", ");
format!(" {entry_fn}({pads}, $nyx_payload)")
}
}
_ => format!(" {entry_fn}($nyx_payload)"),
}
}
/// Best-effort guess at the class name from the entry source.
///
/// Walks every `class Foo` declaration and picks the one whose body
/// contains `def {entry_name}` (the class that actually defines the
/// entry method). When no class hosts the entry method — or the
/// entry name is empty — falls back to the first class declaration,
/// then to `"Entry"`.
fn entry_class_from_spec(spec: &HarnessSpec) -> String {
let src = read_entry_source(&spec.entry_file);
parse_class_hosting_method(&src, &spec.entry_name)
.or_else(|| parse_first_class_name(&src))
.unwrap_or_else(|| "Entry".to_owned())
}
fn parse_class_hosting_method(source: &str, entry_name: &str) -> Option<String> {
if entry_name.is_empty() {
return None;
}
let needle = format!("def {entry_name}");
// Walk every line, remembering the most-recently-seen class
// declaration. When we encounter `def {entry_name}`, return the
// last-seen class — that is the closest enclosing class scope.
// Coarse but correct for the per-shape fixtures (no nested classes).
let mut last_class: Option<String> = None;
for line in source.lines() {
let l = line.trim_start();
if let Some(rest) = l.strip_prefix("class ") {
let name: String = rest
.chars()
.take_while(|c| c.is_alphanumeric() || *c == '_')
.collect();
if !name.is_empty() {
last_class = Some(name);
}
continue;
}
if l.contains(&needle) {
return last_class.clone();
}
}
None
}
fn parse_first_class_name(source: &str) -> Option<String> {
for line in source.lines() {
let l = line.trim_start();
if let Some(rest) = l.strip_prefix("class ") {
let name: String = rest
.chars()
.take_while(|c| c.is_alphanumeric() || *c == '_')
.collect();
if !name.is_empty() {
return Some(name);
}
}
}
None
}
#[cfg(test)]
mod tests {
use super::*;
use crate::dynamic::spec::{EntryKind, EntryKindTag, HarnessSpec, PayloadSlot};
use crate::labels::Cap;
use crate::symbol::Lang;
fn make_spec(payload_slot: PayloadSlot) -> HarnessSpec {
HarnessSpec {
finding_id: "rb000000000001".into(),
entry_file: "src/login.rb".into(),
entry_name: "login".into(),
entry_kind: EntryKind::Function,
lang: Lang::Ruby,
toolchain_id: "ruby-3".into(),
payload_slot,
expected_cap: Cap::SQL_QUERY,
constraint_hints: vec![],
sink_file: "src/login.rb".into(),
sink_line: 10,
spec_hash: "rb000000000001".into(),
derivation: crate::dynamic::spec::SpecDerivationStrategy::FromFlowSteps,
stubs_required: vec![],
framework: None,
java_toolchain: crate::dynamic::spec::JavaToolchain::default(),
}
}
#[test]
fn entry_kinds_supported_is_non_empty() {
assert!(!RubyEmitter.entry_kinds_supported().is_empty());
assert!(
RubyEmitter
.entry_kinds_supported()
.contains(&EntryKindTag::Function)
);
assert!(
RubyEmitter
.entry_kinds_supported()
.contains(&EntryKindTag::HttpRoute)
);
assert!(
RubyEmitter
.entry_kinds_supported()
.contains(&EntryKindTag::CliSubcommand)
);
}
#[test]
fn entry_kind_hint_names_attempted_and_phase() {
let hint = RubyEmitter.entry_kind_hint(EntryKindTag::LibraryApi);
assert!(hint.contains("LibraryApi"));
assert!(hint.contains("Phase 15"));
}
#[test]
fn emit_produces_source() {
let spec = make_spec(PayloadSlot::Param(0));
let harness = emit(&spec).unwrap();
assert!(harness.source.contains("nyx_payload"));
assert!(harness.source.contains("require_relative"));
assert!(harness.source.contains("login($nyx_payload)"));
assert_eq!(harness.filename, "harness.rb");
assert_eq!(harness.command, vec!["ruby", "harness.rb"]);
}
#[test]
fn emit_entry_subpath_is_entry_rb() {
let spec = make_spec(PayloadSlot::Param(0));
let harness = emit(&spec).unwrap();
assert_eq!(harness.entry_subpath, Some("entry.rb".to_owned()));
}
#[test]
fn emit_env_var_slot() {
let spec = make_spec(PayloadSlot::EnvVar("DB_HOST".into()));
let harness = emit(&spec).unwrap();
assert!(harness.source.contains("ENV[\"DB_HOST\"]"));
assert!(harness.source.contains("login()"));
}
#[test]
fn emit_stdin_is_unsupported() {
let spec = make_spec(PayloadSlot::Stdin);
let err = emit(&spec).unwrap_err();
assert_eq!(err, UnsupportedReason::PayloadSlotUnsupported);
}
// ── Phase 15: shape detection ────────────────────────────────────────────
fn make_spec_with(kind: EntryKind, name: &str, entry_file: &str) -> HarnessSpec {
let mut s = make_spec(PayloadSlot::Param(0));
s.entry_kind = kind;
s.entry_name = name.to_owned();
s.entry_file = entry_file.to_owned();
s
}
#[test]
fn shape_detect_sinatra_route() {
let src = "require 'sinatra'\nget '/run' do\n params['p']\nend\n";
let spec = make_spec_with(EntryKind::HttpRoute, "run", "entry.rb");
assert_eq!(RubyShape::detect(&spec, src), RubyShape::SinatraRoute);
}
#[test]
fn shape_detect_rails_action() {
let src = "class UsersController < ApplicationController\n def index\n @user = params[:p]\n end\nend\n";
let spec = make_spec_with(EntryKind::HttpRoute, "index", "entry.rb");
assert_eq!(RubyShape::detect(&spec, src), RubyShape::RailsAction);
}
#[test]
fn shape_detect_rack_middleware() {
let src = "class MyMiddleware\n def call(env)\n [200, {}, ['ok']]\n end\nend\n";
let spec = make_spec_with(EntryKind::HttpRoute, "call", "entry.rb");
assert_eq!(RubyShape::detect(&spec, src), RubyShape::RackMiddleware);
}
#[test]
fn shape_detect_controller_method() {
let src = "class Login\n def authenticate(payload)\n payload\n end\nend\n";
let spec = make_spec_with(EntryKind::Function, "authenticate", "entry.rb");
assert_eq!(RubyShape::detect(&spec, src), RubyShape::ControllerMethod);
}
#[test]
fn shape_detect_generic_fallback() {
let src = "def login(p)\n p\nend\n";
let spec = make_spec_with(EntryKind::Function, "login", "entry.rb");
assert_eq!(RubyShape::detect(&spec, src), RubyShape::Generic);
}
#[test]
fn sinatra_shape_uses_route_registry() {
let spec = make_spec_with(EntryKind::HttpRoute, "run", "entry.rb");
let src = generate_source(&spec, RubyShape::SinatraRoute);
assert!(src.contains("$nyx_sinatra_routes"));
}
#[test]
fn rack_shape_builds_env_hash() {
let mut spec = make_spec_with(EntryKind::HttpRoute, "call", "entry.rb");
spec.payload_slot = PayloadSlot::QueryParam("payload".into());
let src = generate_source(&spec, RubyShape::RackMiddleware);
assert!(src.contains("REQUEST_METHOD"));
assert!(src.contains("rack.input"));
}
#[test]
fn rails_shape_invokes_action_on_instance() {
let spec = make_spec_with(EntryKind::HttpRoute, "index", "entry.rb");
let src = generate_source(&spec, RubyShape::RailsAction);
assert!(src.contains("instance.send"));
}
#[test]
fn controller_shape_calls_method() {
let spec = make_spec_with(EntryKind::Function, "authenticate", "entry.rb");
let src = generate_source(&spec, RubyShape::ControllerMethod);
assert!(src.contains("instance.send"));
}
#[test]
fn parse_first_class_name_picks_up_class_decl() {
assert_eq!(
parse_first_class_name("class Foo\nend\n"),
Some("Foo".to_owned())
);
assert_eq!(
parse_first_class_name("class Bar < Base\nend\n"),
Some("Bar".to_owned())
);
assert_eq!(parse_first_class_name("def foo\nend\n"), None);
}
#[test]
fn emit_splices_probe_shim_and_installs_crash_guard() {
let spec = make_spec(PayloadSlot::Param(0));
let h = emit(&spec).unwrap();
assert!(
h.source.contains("__nyx_probe shim (Phase 06 — Track C.1"),
"probe_shim banner missing from generated harness.rb — splicing regressed",
);
assert!(
h.source
.contains("def __nyx_install_crash_guard(sink_callee)"),
"install_crash_guard definition missing from generated harness.rb",
);
assert!(
h.source.contains("__nyx_install_crash_guard('login')"),
"install_crash_guard call site missing or wrong callee in harness body",
);
let install_pos = h.source.find("__nyx_install_crash_guard('login')").unwrap();
let payload_pos = h.source.find("$nyx_payload = nyx_payload").unwrap();
// The invocation is `login($nyx_payload)` for the default Generic shape.
let invoke_pos = h.source.find("login($nyx_payload)").unwrap();
assert!(
payload_pos < install_pos && install_pos < invoke_pos,
"install_crash_guard ordering wrong: payload_pos={payload_pos} install_pos={install_pos} invoke_pos={invoke_pos}",
);
}
#[test]
fn probe_shim_publishes_stub_http_recorder() {
let shim = probe_shim();
assert!(
shim.contains("def __nyx_stub_http_record"),
"Ruby probe shim must define __nyx_stub_http_record"
);
assert!(
shim.contains("ENV['NYX_HTTP_LOG']"),
"Ruby HTTP recorder must read NYX_HTTP_LOG to find the side-channel log"
);
assert!(
shim.contains("# method: "),
"Ruby HTTP recorder must emit a hash-prefixed method detail line"
);
assert!(
shim.contains("# url: "),
"Ruby HTTP recorder must emit a hash-prefixed url detail line"
);
}
#[test]
fn probe_shim_publishes_stub_sql_recorder() {
let shim = probe_shim();
assert!(
shim.contains("def __nyx_stub_sql_record"),
"Ruby probe shim must define __nyx_stub_sql_record"
);
assert!(
shim.contains("ENV['NYX_SQL_LOG']"),
"Ruby SQL recorder must read NYX_SQL_LOG to find the side-channel log"
);
assert!(
shim.contains("line.end_with?"),
"Ruby SQL recorder must guarantee a trailing newline on the query line so SqlStub::drain_events frames each record"
);
}
#[test]
fn chain_step_splices_probe_shim_for_composite_reverify() {
let step = chain_step(Some(b"<prev>"), None);
assert!(
step.source.contains("__nyx_probe"),
"Ruby chain step must splice the probe shim"
);
assert!(
step.source.contains("ENV[\"NYX_PREV_OUTPUT\"]"),
"Ruby chain step must keep its NYX_PREV_OUTPUT forwarder"
);
let shim_pos = step.source.find("__nyx_probe").unwrap();
let driver_pos = step.source.find("ENV[\"NYX_PREV_OUTPUT\"]").unwrap();
assert!(
shim_pos < driver_pos,
"probe shim must come before the driver so a sink rewrite has the shim's helpers in scope"
);
}
// ── Phase 08 / 09 tier-(a) Ruby emitter tests ────────────────────────────
fn make_header_spec(entry_file: &str, entry_name: &str) -> HarnessSpec {
let mut spec = make_spec(PayloadSlot::Param(0));
spec.expected_cap = Cap::HEADER_INJECTION;
spec.entry_file = entry_file.to_owned();
spec.entry_name = entry_name.to_owned();
spec
}
fn make_redirect_spec(entry_file: &str, entry_name: &str) -> HarnessSpec {
let mut spec = make_spec(PayloadSlot::Param(0));
spec.expected_cap = Cap::OPEN_REDIRECT;
spec.entry_file = entry_file.to_owned();
spec.entry_name = entry_name.to_owned();
spec
}
#[test]
fn emit_header_injection_harness_routes_through_fixture_when_rack_required() {
let dir = std::env::temp_dir().join("nyx_phase08_rb_test_drive_fixture");
let _ = std::fs::remove_dir_all(&dir);
std::fs::create_dir_all(&dir).unwrap();
let entry = dir.join("vuln.rb");
std::fs::write(
&entry,
"require 'rack'\n\
def run(value)\n r = Rack::Response.new\n r.set_header('Set-Cookie', value)\n r\nend\n",
)
.unwrap();
let h = emit_header_injection_harness(&make_header_spec(
entry.to_str().unwrap(),
"run",
));
assert!(
h.source.contains("def _nyx_header_via_fixture(payload)"),
"tier-(a) harness must define the fixture-routing helper: {}",
h.source
);
assert!(
h.source.contains("Rack::Response.prepend(patcher)"),
"tier-(a) harness must prepend the captor onto Rack::Response: {}",
h.source
);
assert!(
h.source.contains("require_relative './vuln'"),
"tier-(a) harness must require the fixture by its file stem: {}",
h.source
);
assert!(
h.source.contains("Object.new.__send__(:'run', payload)"),
"tier-(a) harness must invoke the named entry function via __send__: {}",
h.source
);
assert!(
h.source.contains("captured = _nyx_header_via_fixture(payload)"),
"harness main must call the fixture-routing helper first: {}",
h.source
);
assert!(
h.source.contains("value = payload\n _nyx_header_probe(name, value)"),
"fallback path must keep the synthetic probe: {}",
h.source
);
let _ = std::fs::remove_dir_all(&dir);
}
#[test]
fn emit_header_injection_harness_falls_back_when_rack_not_required() {
let dir = std::env::temp_dir().join("nyx_phase08_rb_test_no_rack");
let _ = std::fs::remove_dir_all(&dir);
std::fs::create_dir_all(&dir).unwrap();
let entry = dir.join("vuln.rb");
std::fs::write(&entry, "def run(value)\n value\nend\n").unwrap();
let h = emit_header_injection_harness(&make_header_spec(
entry.to_str().unwrap(),
"run",
));
assert!(
!h.source.contains("Rack::Response.prepend"),
"fallback path must not patch Rack::Response: {}",
h.source
);
assert!(
!h.source.contains("def _nyx_header_via_fixture"),
"fallback path must not define the fixture-routing helper: {}",
h.source
);
assert!(
h.source.contains("value = payload\n _nyx_header_probe(name, value)"),
"fallback path must keep the synthetic probe: {}",
h.source
);
let _ = std::fs::remove_dir_all(&dir);
}
#[test]
fn emit_header_injection_harness_derives_basename_from_entry_file() {
let dir = std::env::temp_dir().join("nyx_phase08_rb_test_basename_derive");
let _ = std::fs::remove_dir_all(&dir);
std::fs::create_dir_all(&dir).unwrap();
let entry = dir.join("benign.rb");
std::fs::write(
&entry,
"require 'rack'\n\
def run(v)\n Rack::Response.new\nend\n",
)
.unwrap();
let h = emit_header_injection_harness(&make_header_spec(
entry.to_str().unwrap(),
"run",
));
assert!(
h.source.contains("require_relative './benign'"),
"basename must come from the entry-file stem: {}",
h.source
);
let _ = std::fs::remove_dir_all(&dir);
}
#[test]
fn emit_open_redirect_harness_routes_through_fixture_when_rack_required() {
let dir = std::env::temp_dir().join("nyx_phase09_rb_test_drive_fixture");
let _ = std::fs::remove_dir_all(&dir);
std::fs::create_dir_all(&dir).unwrap();
let entry = dir.join("vuln.rb");
std::fs::write(
&entry,
"require 'rack'\n\
def run(value)\n r = Rack::Response.new\n r.redirect(value)\n r\nend\n",
)
.unwrap();
let h = emit_open_redirect_harness(&make_redirect_spec(
entry.to_str().unwrap(),
"run",
));
assert!(
h.source.contains("def _nyx_redirect_via_fixture(payload)"),
"tier-(a) harness must define the fixture-routing helper: {}",
h.source
);
assert!(
h.source.contains("Rack::Response.prepend(patcher)"),
"tier-(a) harness must prepend the captor onto Rack::Response: {}",
h.source
);
assert!(
h.source.contains("require_relative './vuln'"),
"tier-(a) harness must require the fixture by its file stem: {}",
h.source
);
assert!(
h.source.contains("define_method(:redirect)"),
"tier-(a) captor must intercept the redirect method: {}",
h.source
);
assert!(
h.source.contains("captured = _nyx_redirect_via_fixture(payload)"),
"harness main must call the fixture-routing helper first: {}",
h.source
);
assert!(
h.source.contains("location = payload\n _nyx_redirect_probe(location, request_host)"),
"fallback path must keep the synthetic probe: {}",
h.source
);
let _ = std::fs::remove_dir_all(&dir);
}
#[test]
fn emit_open_redirect_harness_falls_back_when_rack_not_required() {
let dir = std::env::temp_dir().join("nyx_phase09_rb_test_no_rack");
let _ = std::fs::remove_dir_all(&dir);
std::fs::create_dir_all(&dir).unwrap();
let entry = dir.join("vuln.rb");
std::fs::write(&entry, "def run(value)\n value\nend\n").unwrap();
let h = emit_open_redirect_harness(&make_redirect_spec(
entry.to_str().unwrap(),
"run",
));
assert!(
!h.source.contains("Rack::Response.prepend"),
"fallback path must not patch Rack::Response: {}",
h.source
);
assert!(
!h.source.contains("def _nyx_redirect_via_fixture"),
"fallback path must not define the fixture-routing helper: {}",
h.source
);
assert!(
h.source.contains("location = payload\n _nyx_redirect_probe(location, request_host)"),
"fallback path must keep the synthetic probe: {}",
h.source
);
let _ = std::fs::remove_dir_all(&dir);
}
#[test]
fn emit_open_redirect_harness_ships_follow_location_helper() {
let dir = std::env::temp_dir().join("nyx_phase09_rb_test_follow_location");
let _ = std::fs::remove_dir_all(&dir);
std::fs::create_dir_all(&dir).unwrap();
let entry = dir.join("vuln.rb");
std::fs::write(
&entry,
"require 'rack'\n\
def run(value)\n r = Rack::Response.new\n r.redirect(value)\n r\nend\n",
)
.unwrap();
let h = emit_open_redirect_harness(&make_redirect_spec(
entry.to_str().unwrap(),
"run",
));
assert!(
h.source.contains("def _nyx_follow_location(location)"),
"OPEN_REDIRECT harness must declare the _nyx_follow_location helper: {}",
h.source
);
assert!(
h.source.contains("require 'net/http'") && h.source.contains("require 'uri'"),
"OPEN_REDIRECT harness must require net/http and uri for the loopback follow: {}",
h.source
);
assert!(
h.source.contains("Net::HTTP.start(uri.host, uri.port"),
"follow-location helper must invoke Net::HTTP.start: {}",
h.source
);
assert!(
h.source.contains("start_with?('http://127.0.0.1')")
&& h.source.contains("start_with?('http://localhost')")
&& h.source.contains("start_with?('http://host-gateway')"),
"follow-location helper must gate on loopback host prefixes: {}",
h.source
);
assert!(
h.source.contains("_nyx_redirect_probe(location, request_host)\n _nyx_follow_location(location)"),
"tier-(a) must follow the captured Location after emitting the probe: {}",
h.source
);
let _ = std::fs::remove_dir_all(&dir);
}
}