path: root/tests/test_rdap.py

# Copyright (C) 2026 Danilo M. <danix@danix.xyz>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
"""Tests for the RDAP protocol module."""

import email
import unittest
import urllib.error
import urllib.request

from abusectl import rdap


class RedirectPolicy(unittest.TestCase):
    """A redirect is remote data directing our next request.

    urllib.request.Request is used rather than a hand-rolled fake, because
    HTTPRedirectHandler reads attributes (origin_req_host, unverifiable,
    timeout) that a fake would have to reproduce exactly to prove anything.
    """

    def _request(self):
        return urllib.request.Request("https://rdap.example.invalid/ip/192.0.2.1")

    def test_an_https_to_http_downgrade_is_refused(self):
        handler = rdap._NoDowngradeRedirectHandler()
        with self.assertRaises(urllib.error.HTTPError):
            handler.redirect_request(
                self._request(), None, 302, "Found",
                email.message_from_string(""),
                "http://rdap.example.invalid/ip/192.0.2.1",
            )

    def test_an_https_to_https_redirect_is_allowed(self):
        handler = rdap._NoDowngradeRedirectHandler()
        result = handler.redirect_request(
            self._request(), None, 302, "Found",
            email.message_from_string(""),
            "https://other.example.invalid/ip/192.0.2.1",
        )
        self.assertIsNotNone(result)


import json
import tempfile
import time
from pathlib import Path


class Bootstrap(unittest.TestCase):
    def setUp(self):
        self.tmp = tempfile.TemporaryDirectory()
        self.cache = Path(self.tmp.name)
        self.addCleanup(self.tmp.cleanup)

    def test_a_missing_file_is_fetched_and_cached(self):
        calls = []

        def fetch(url):
            calls.append(url)
            return {"services": []}

        data = rdap.bootstrap("ipv4", cache_root=self.cache, fetch=fetch)

        self.assertEqual(data, {"services": []})
        self.assertEqual(calls, ["https://data.iana.org/rdap/ipv4.json"])
        self.assertTrue((self.cache / "ipv4.json").exists())

    def test_a_fresh_cache_is_not_refetched(self):
        (self.cache / "ipv4.json").write_text(json.dumps({"services": ["cached"]}))

        def fetch(url):
            raise AssertionError(f"should not have fetched {url}")

        data = rdap.bootstrap("ipv4", cache_root=self.cache, fetch=fetch)
        self.assertEqual(data, {"services": ["cached"]})

    def test_a_stale_cache_is_refetched(self):
        path = self.cache / "ipv4.json"
        path.write_text(json.dumps({"services": ["old"]}))
        old = time.time() - (rdap._BOOTSTRAP_TTL + 60)
        import os
        os.utime(path, (old, old))

        data = rdap.bootstrap(
            "ipv4", cache_root=self.cache, fetch=lambda url: {"services": ["new"]}
        )
        self.assertEqual(data, {"services": ["new"]})

    def test_a_failed_refetch_falls_back_to_the_stale_copy(self):
        """Losing IANA must not stop the user filing a report.

        Last week's map is almost certainly still correct, and a stale
        bootstrap fails safe: the worst case is querying a server that has
        moved, which misses and reads as no contact.
        """
        path = self.cache / "ipv4.json"
        path.write_text(json.dumps({"services": ["old"]}))
        old = time.time() - (rdap._BOOTSTRAP_TTL + 60)
        import os
        os.utime(path, (old, old))

        def fetch(url):
            raise OSError("network is unreachable")

        data = rdap.bootstrap("ipv4", cache_root=self.cache, fetch=fetch)
        self.assertEqual(data, {"services": ["old"]})

    def test_a_failed_fetch_with_no_cache_raises(self):
        def fetch(url):
            raise OSError("network is unreachable")

        with self.assertRaises(rdap.BootstrapUnavailable):
            rdap.bootstrap("ipv4", cache_root=self.cache, fetch=fetch)


class ServerSelection(unittest.TestCase):
    IPV4 = {
        "services": [
            [["192.0.2.0/24"], ["https://wide.example.invalid/"]],
            [["192.0.2.128/25"], ["https://narrow.example.invalid/"]],
            [["198.51.100.0/24"], ["https://other.example.invalid/"]],
        ]
    }
    DNS = {
        "services": [
            [["invalid"], ["https://registry.example.invalid/"]],
            [["test"], ["https://test.example.invalid/"]],
        ]
    }

    def test_an_address_selects_its_range(self):
        self.assertEqual(
            rdap.server_for_ip("198.51.100.7", self.IPV4),
            "https://other.example.invalid/",
        )

    def test_the_longest_prefix_wins(self):
        """192.0.2.200 is in both /24 and /25; the /25 is more specific.

        Choosing the wider range would ask a registry that has delegated
        the block away, and its answer would name the wrong operator.
        """
        self.assertEqual(
            rdap.server_for_ip("192.0.2.200", self.IPV4),
            "https://narrow.example.invalid/",
        )

    def test_an_unlisted_address_selects_nothing(self):
        self.assertIsNone(rdap.server_for_ip("203.0.113.9", self.IPV4))

    def test_a_tld_selects_its_registry(self):
        self.assertEqual(
            rdap.server_for_tld("invalid", self.DNS),
            "https://registry.example.invalid/",
        )

    def test_tld_matching_ignores_case(self):
        self.assertEqual(
            rdap.server_for_tld("INVALID", self.DNS),
            "https://registry.example.invalid/",
        )

    def test_an_unlisted_tld_selects_nothing(self):
        self.assertIsNone(rdap.server_for_tld("example", self.DNS))


class HostileBootstrap(unittest.TestCase):
    """The bootstrap document comes off the same network as an RDAP response.

    abuse_addresses already treats a response as hostile. These assert the
    same posture for the document that decides WHICH server is asked, which
    is the more valuable one to subvert.
    """

    def test_a_non_string_cidr_does_not_become_a_winning_slash_32(self):
        """ipaddress.ip_network(16909060) returns 1.2.3.4/32 rather than
        raising, and a /32 is the longest possible prefix, so it wins every
        contest. The victim is the user, who would file the phishing report
        to a server the phisher chose."""
        data = {
            "services": [
                [["1.2.3.0/24"], ["https://legit.example.invalid/"]],
                [[16909060], ["https://attacker.example.invalid/"]],
            ]
        }
        self.assertEqual(
            rdap.server_for_ip("1.2.3.4", data),
            "https://legit.example.invalid/",
        )

    def test_a_non_string_tld_name_does_not_crash(self):
        data = {"services": [[[42], ["https://attacker.example.invalid/"]]]}
        self.assertIsNone(rdap.server_for_tld("invalid", data))

    def test_a_malformed_services_value_is_not_fatal(self):
        """One bad response is cached for seven days, so a crash here breaks
        every contacts run until the cache expires."""
        for services in ("abc", [[["192.0.2.0/24"]]], [None], [{"a": 1}],
                         [[5, ["https://u.example.invalid/"]]], 7, None):
            with self.subTest(services=services):
                data = {"services": services}
                self.assertIsNone(rdap.server_for_ip("192.0.2.1", data))
                self.assertIsNone(rdap.server_for_tld("invalid", data))

    def test_a_malformed_entry_does_not_hide_a_good_one(self):
        data = {
            "services": [
                None,
                [[["192.0.2.0/24"]]],
                [["192.0.2.0/24"], ["https://legit.example.invalid/"]],
            ]
        }
        self.assertEqual(
            rdap.server_for_ip("192.0.2.1", data),
            "https://legit.example.invalid/",
        )

    def test_a_plaintext_base_url_is_refused(self):
        """_NoDowngradeRedirectHandler guards redirects only. A bootstrap
        naming an http:// base would send the query in clear text,
        disclosing which netblock the user is investigating."""
        ipv4 = {"services": [[["198.51.100.0/24"],
                              ["http://plaintext.example.invalid/"]]]}
        dns = {"services": [[["invalid"],
                             ["http://plaintext.example.invalid/"]]]}
        self.assertIsNone(rdap.server_for_ip("198.51.100.7", ipv4))
        self.assertIsNone(rdap.server_for_tld("invalid", dns))

    def test_a_non_string_url_is_refused(self):
        ipv4 = {"services": [[["198.51.100.0/24"], [42]]]}
        dns = {"services": [[["invalid"], [42]]]}
        self.assertIsNone(rdap.server_for_ip("198.51.100.7", ipv4))
        self.assertIsNone(rdap.server_for_tld("invalid", dns))

    def test_a_plaintext_base_does_not_hide_an_https_one(self):
        data = {
            "services": [
                [["192.0.2.0/25"], ["http://plaintext.example.invalid/"]],
                [["192.0.2.0/24"], ["https://legit.example.invalid/"]],
            ]
        }
        self.assertEqual(
            rdap.server_for_ip("192.0.2.1", data),
            "https://legit.example.invalid/",
        )

    def test_a_plaintext_base_is_never_queried(self):
        data = {"services": [[["198.51.100.0/24"],
                              ["http://plaintext.example.invalid/"]]]}

        def fetch(url):
            raise AssertionError(f"should not have fetched {url}")

        self.assertIsNone(rdap.query_ip("198.51.100.7", data, fetch=fetch))


def _entity(roles, emails, entities=None):
    """Build an RDAP entity in real jCard shape."""
    properties = [["version", {}, "text", "4.0"]]
    for address in emails:
        properties.append(["email", {}, "text", address])
    entity = {"roles": roles, "vcardArray": ["vcard", properties]}
    if entities:
        entity["entities"] = entities
    return entity


class AbuseExtraction(unittest.TestCase):
    def test_an_abuse_entity_yields_its_address(self):
        response = {"entities": [_entity(["abuse"], ["abuse@example.invalid"])]}
        self.assertEqual(
            rdap.abuse_addresses(response), ["abuse@example.invalid"]
        )

    def test_a_nested_abuse_entity_is_found(self):
        """The abuse entity is usually a child of the organisation entity."""
        response = {
            "entities": [
                _entity(
                    ["registrant"], [],
                    entities=[_entity(["abuse"], ["abuse@example.invalid"])],
                )
            ]
        }
        self.assertEqual(
            rdap.abuse_addresses(response), ["abuse@example.invalid"]
        )

    def test_a_technical_only_response_yields_nothing(self):
        """A technical contact is a named human who never volunteered to
        receive abuse mail. Mailing them is useless and is a small privacy
        harm to an uninvolved third party."""
        response = {"entities": [_entity(["technical"], ["someone@example.invalid"])]}
        self.assertEqual(rdap.abuse_addresses(response), [])

    def test_every_abuse_address_is_kept(self):
        """Some netblocks publish two desks, and picking one arbitrarily
        can drop the one that would have answered."""
        response = {
            "entities": [
                _entity(["abuse"], ["one@example.invalid", "two@example.invalid"])
            ]
        }
        self.assertEqual(
            rdap.abuse_addresses(response),
            ["one@example.invalid", "two@example.invalid"],
        )

    def test_a_newline_in_an_address_is_rejected(self):
        """The address becomes a mail recipient in report and submit, so a
        CRLF here is header injection into mail this tool sends."""
        response = {
            "entities": [
                _entity(["abuse"], ["abuse@example.invalid\r\nBcc: victim@example.org"])
            ]
        }
        self.assertEqual(rdap.abuse_addresses(response), [])

    def test_a_bare_control_character_in_an_address_is_rejected(self):
        """The CRLF case above is rejected by parseaddr itself, so it passes
        even with the control-character check deleted. These two are passed
        straight through by parseaddr and reach a mail header raw, so this
        is the case that actually holds _valid_address's own defence."""
        for raw in ("abuse@example.invalid\x0b", "ab\x0cuse@example.invalid"):
            with self.subTest(raw=raw):
                response = {"entities": [_entity(["abuse"], [raw])]}
                self.assertEqual(rdap.abuse_addresses(response), [])

    def test_a_non_address_is_rejected(self):
        response = {"entities": [_entity(["abuse"], ["not an address"])]}
        self.assertEqual(rdap.abuse_addresses(response), [])

    def test_recursion_is_depth_capped(self):
        """Remote JSON must not be able to hang the tool."""
        deep = _entity(["abuse"], ["deep@example.invalid"])
        for _ in range(10):
            deep = _entity(["registrant"], [], entities=[deep])
        self.assertEqual(rdap.abuse_addresses({"entities": [deep]}), [])

    def test_duplicate_addresses_collapse(self):
        response = {
            "entities": [
                _entity(["abuse"], ["abuse@example.invalid"]),
                _entity(["abuse"], ["abuse@example.invalid"]),
            ]
        }
        self.assertEqual(
            rdap.abuse_addresses(response), ["abuse@example.invalid"]
        )


class Query(unittest.TestCase):
    IPV4 = {"services": [[["198.51.100.0/24"], ["https://rir.example.invalid/"]]]}
    DNS = {"services": [[["invalid"], ["https://registry.example.invalid/"]]]}

    def test_an_ip_query_hits_the_selected_server(self):
        calls = []

        def fetch(url):
            calls.append(url)
            return {"handle": "NET-1", "entities": []}

        result = rdap.query_ip("198.51.100.7", self.IPV4, fetch=fetch)

        self.assertEqual(calls, ["https://rir.example.invalid/ip/198.51.100.7"])
        self.assertEqual(result["handle"], "NET-1")

    def test_an_unlisted_ip_is_not_queried(self):
        def fetch(url):
            raise AssertionError(f"should not have fetched {url}")

        self.assertIsNone(rdap.query_ip("203.0.113.9", self.IPV4, fetch=fetch))

    def test_the_label_walk_stops_at_the_first_answer(self):
        """mail.deep.example.invalid is not registrable; example.invalid is.

        The registry is the authority on what is registrable, which is why
        this walks rather than carrying a Public Suffix List that would go
        stale weekly.
        """
        calls = []

        def fetch(url):
            calls.append(url)
            if url.endswith("/domain/example.invalid"):
                return {"handle": "DOM-1", "entities": []}
            raise urllib.error.HTTPError(url, 404, "Not Found", {}, None)

        result, queried = rdap.query_domain(
            "mail.deep.example.invalid", self.DNS, fetch=fetch
        )

        self.assertEqual(queried, "example.invalid")
        self.assertEqual(result["handle"], "DOM-1")
        self.assertEqual(len(calls), 3)

    def test_the_walk_never_queries_a_bare_tld(self):
        calls = []

        def fetch(url):
            calls.append(url)
            raise urllib.error.HTTPError(url, 404, "Not Found", {}, None)

        result, queried = rdap.query_domain(
            "deep.example.invalid", self.DNS, fetch=fetch
        )

        self.assertIsNone(result)
        self.assertNotIn("https://registry.example.invalid/domain/invalid", calls)

    def test_a_tld_with_no_server_is_not_queried(self):
        def fetch(url):
            raise AssertionError(f"should not have fetched {url}")

        result, queried = rdap.query_domain(
            "example.test", self.DNS, fetch=fetch
        )
        self.assertIsNone(result)

    def test_the_walk_is_capped(self):
        calls = []

        def fetch(url):
            calls.append(url)
            raise urllib.error.HTTPError(url, 404, "Not Found", {}, None)

        # Twelve labels, so the bare-TLD guard alone would allow eleven
        # attempts and only the cap can stop the walk at five. The expected
        # count is hard-coded: reading rdap._MAX_LABEL_WALK here would move
        # the assertion along with the mutation and the test could not fail.
        host = "a.b.c.d.e.f.g.h.i.j.example.invalid"
        rdap.query_domain(host, self.DNS, fetch=fetch)
        self.assertEqual(len(calls), 5)


if __name__ == "__main__":
    unittest.main()