Files
hermes-webui/tests/test_v050258_opus_followups.py
2026-05-04 00:06:58 -07:00

136 lines
5.8 KiB
Python

"""Regression tests for v0.50.258 Opus pre-release follow-up.
PR #1419 introduced server-side `?next=` redirect after session expiry. The
initial implementation built the outer `next` parameter via:
_next = quote(path, safe='/:@!$&\'()*+,;=')
if query:
_next += '?' + query
location = 'login?next=' + quote(_next, safe='/:@!$&\'()*+,;=?')
Two problems with this shape:
1. The inner `?` was kept literal because both `quote()` calls had `?` in
their `safe` set. Combined with `&` also being kept literal, paths with
multi-param queries (`/api/sessions?limit=50&offset=0`) round-tripped as
`/api/sessions?limit=50` — the rest got eaten as a top-level outer query
parameter the login page ignored.
2. Attacker-controlled paths with embedded `&next=...` could inject a second
top-level `next` parameter. Browsers' URLSearchParams.get() returns the
first-match (safe), Python's parse_qs returns last-match (unsafe). The
downstream `_safeNextPath()` rejects non-`/` prefixes which closed the
actual exploit, but the parser-divergence is a footgun.
Fix: percent-encode the entire `path?query` blob with `safe='/'`, so `?`,
`&`, `=` all get encoded. The outer `next` then holds exactly one
path-with-query string that the browser auto-decodes once.
"""
from __future__ import annotations
import re
import urllib.parse as _urlparse
from pathlib import Path
REPO = Path(__file__).resolve().parents[1]
# ── 1: source-level pin: redirect uses safe='/' encoding ────────────────────
def test_login_redirect_uses_path_only_safe_encoding():
"""The check_auth redirect must encode `?` and `&` so multi-param query
strings round-trip correctly. Negative pattern guards revert to the
original `safe='/:@!$&\'()*+,;=?'` shape."""
src = (REPO / "api" / "auth.py").read_text(encoding="utf-8")
redirect_idx = src.find("login?next=")
assert redirect_idx != -1, "login redirect missing"
block = src[max(0, redirect_idx - 1200) : redirect_idx + 600]
# Must use safe='/' (path-separators only).
assert "safe='/'" in block, (
"check_auth must encode `?` and `&` in the next= parameter so multi-param "
"query strings round-trip. safe='/' is the correct encoding shape."
)
# Must NOT use the broad safe set that keeps `?` and `&` literal.
assert "safe='/:@!$&\\'()*+,;=?'" not in block, (
"check_auth must not use the broad safe='/:@!$&\\'()*+,;=?' encoding — "
"that keeps `?` and `&` literal, which truncates multi-param queries "
"and creates a parser-divergence footgun."
)
# ── 2: behavioral round-trip ────────────────────────────────────────────────
def _build_redirect_like_check_auth(path: str, query: str) -> str:
"""Mirror api.auth.check_auth's redirect construction so we can assert
the round-trip without spinning up a server."""
_path_with_query = path or "/"
if query:
_path_with_query += "?" + query
_next = _urlparse.quote(_path_with_query, safe="/")
return "login?next=" + _next
def _browser_searchparams_get_next(location: str) -> str:
"""Mirror the browser's URLSearchParams.get('next') behaviour."""
parsed = _urlparse.urlparse("https://host" + location)
qs = _urlparse.parse_qs(parsed.query, keep_blank_values=True)
values = qs.get("next", [])
return values[0] if values else None
def test_redirect_roundtrip_simple_path():
location = _build_redirect_like_check_auth("/foo/bar", "")
assert _browser_searchparams_get_next(location) == "/foo/bar"
def test_redirect_roundtrip_single_query_param():
location = _build_redirect_like_check_auth("/foo/bar", "baz=qux")
assert _browser_searchparams_get_next(location) == "/foo/bar?baz=qux"
def test_redirect_roundtrip_multi_query_params():
"""REGRESSION: pre-fix, this round-tripped to `/api/sessions?limit=50`
(offset got eaten as a top-level outer query)."""
location = _build_redirect_like_check_auth("/api/sessions", "limit=50&offset=0")
got = _browser_searchparams_get_next(location)
assert got == "/api/sessions?limit=50&offset=0", (
f"multi-param query round-trip broken: got {got!r}, expected the full string"
)
def test_redirect_roundtrip_attacker_controlled_next_injection_neutralized():
"""REGRESSION: pre-fix, an attacker-controlled `&next=https://evil.com`
in the source query injected a second top-level `next` parameter.
Browsers parse first-match (benign), Python parses last-match (the evil
value) — parser-divergence footgun even if downstream guards reject it."""
location = _build_redirect_like_check_auth(
"/admin", "action=foo&next=https://evil.com"
)
got = _browser_searchparams_get_next(location)
# The entire string is preserved as the FIRST `next` value.
assert got == "/admin?action=foo&next=https://evil.com"
# And there is exactly ONE top-level `next` parameter.
parsed = _urlparse.urlparse("https://host" + location)
qs = _urlparse.parse_qs(parsed.query, keep_blank_values=True)
assert len(qs.get("next", [])) == 1, (
f"expected exactly one top-level `next` parameter, got {qs.get('next')}"
)
# _safeNextPath() in login.js (charAt(0)==='/' and charAt(1)!=='/') would
# accept this as a valid same-origin path. The /admin page receives the
# benign embedded query and the evil URL never becomes a redirect target.
def test_redirect_session_ttl_30_days():
"""Pin the SESSION_TTL constant to the 30-day value introduced by #1419."""
src = (REPO / "api" / "auth.py").read_text(encoding="utf-8")
assert "SESSION_TTL = 86400 * 30" in src, (
"SESSION_TTL must be 30 days (86400 * 30) per #1419. Reverting to "
"24h would re-introduce the daily-kick-out UX regression."
)