add tests for archive TAMs

src/borg/testsuite/archiver/checks.py

@@ -8,7 +8,7 @@ import pytest
 from ...cache import Cache, LocalCache
 from ...constants import *  # NOQA
 from ...crypto.key import TAMRequiredError
-from ...helpers import Location, get_security_dir, bin_to_hex
+from ...helpers import Location, get_security_dir, bin_to_hex, archive_ts_now
 from ...helpers import EXIT_ERROR
 from ...helpers import msgpack
 from ...manifest import Manifest, MandatoryFeatureUnsupported
@@ -322,7 +322,7 @@ def test_check_cache(archivers, request):
         check_cache(archiver)
 
 
-#  Begin manifest tests
+#  Begin manifest TAM tests
 def spoof_manifest(repository):
     with repository:
         manifest = Manifest.load(repository, Manifest.NO_OPERATION_CHECK)
@@ -380,6 +380,62 @@ def test_not_required(archiver):
         cmd(archiver, "rlist")
 
 
+#  Begin archive TAM tests
+def write_archive_without_tam(repository, archive_name):
+    manifest = Manifest.load(repository, Manifest.NO_OPERATION_CHECK)
+    archive_data = msgpack.packb(
+        {
+            "version": 2,
+            "name": archive_name,
+            "item_ptrs": [],
+            "command_line": "",
+            "hostname": "",
+            "username": "",
+            "time": archive_ts_now().isoformat(timespec="microseconds"),
+            "size": 0,
+            "nfiles": 0,
+        }
+    )
+    archive_id = manifest.repo_objs.id_hash(archive_data)
+    cdata = manifest.repo_objs.format(archive_id, {}, archive_data)
+    repository.put(archive_id, cdata)
+    manifest.archives[archive_name] = (archive_id, datetime.now())
+    manifest.write()
+    repository.commit(compact=False)
+
+
+def test_check_rebuild_manifest(archiver):
+    cmd(archiver, "rcreate", RK_ENCRYPTION)
+    create_src_archive(archiver, "archive_tam")
+    repository = Repository(archiver.repository_path, exclusive=True)
+    with repository:
+        write_archive_without_tam(repository, "archive_no_tam")
+        repository.delete(Manifest.MANIFEST_ID)  # kill manifest, so check has to rebuild it
+        repository.commit(compact=False)
+    cmd(archiver, "check", "--repair")
+    output = cmd(archiver, "rlist", "--format='{name} tam:{tam}{NL}'")
+    assert "archive_tam tam:verified" in output  # TAM-verified archive is in rebuilt manifest
+    assert "archive_no_tam" not in output  # check got rid of untrusted not TAM-verified archive
+
+
+def test_check_rebuild_refcounts(archiver):
+    cmd(archiver, "rcreate", RK_ENCRYPTION)
+    create_src_archive(archiver, "archive_tam")
+    archive_id_pre_check = cmd(archiver, "rlist", "--format='{name} {id}{NL}'")
+    repository = Repository(archiver.repository_path, exclusive=True)
+    with repository:
+        write_archive_without_tam(repository, "archive_no_tam")
+    output = cmd(archiver, "rlist", "--format='{name} tam:{tam}{NL}'")
+    assert "archive_tam tam:verified" in output  # good
+    assert "archive_no_tam tam:none" in output  # could be borg < 1.0.9 archive or fake
+    cmd(archiver, "check", "--repair")
+    output = cmd(archiver, "rlist", "--format='{name} tam:{tam}{NL}'")
+    assert "archive_tam tam:verified" in output  # TAM-verified archive still there
+    assert "archive_no_tam" not in output  # check got rid of untrusted not TAM-verified archive
+    archive_id_post_check = cmd(archiver, "rlist", "--format='{name} {id}{NL}'")
+    assert archive_id_post_check == archive_id_pre_check  # rebuild_refcounts didn't change archive_tam archive id
+
+
 # Begin Remote Tests
 def test_remote_repo_restrict_to_path(remote_archiver):
     original_location, repo_path = remote_archiver.repository_location, remote_archiver.repository_path

src/borg/testsuite/key.py

@@ -11,13 +11,8 @@ from ..crypto.key import AEADKeyBase
 from ..crypto.key import AESOCBRepoKey, AESOCBKeyfileKey, CHPORepoKey, CHPOKeyfileKey
 from ..crypto.key import Blake2AESOCBRepoKey, Blake2AESOCBKeyfileKey, Blake2CHPORepoKey, Blake2CHPOKeyfileKey
 from ..crypto.key import ID_HMAC_SHA_256, ID_BLAKE2b_256
-from ..crypto.key import (
+from ..crypto.key import TAMRequiredError, TAMInvalid, TAMUnsupportedSuiteError, ArchiveTAMInvalid
-    TAMRequiredError,
+from ..crypto.key import UnsupportedManifestError, UnsupportedKeyFormatError
-    TAMInvalid,
-    TAMUnsupportedSuiteError,
-    UnsupportedManifestError,
-    UnsupportedKeyFormatError,
-)
 from ..crypto.key import identify_key
 from ..crypto.low_level import IntegrityError as IntegrityErrorBase
 from ..helpers import IntegrityError
@@ -281,6 +276,8 @@ class TestTAM:
         blob = msgpack.packb({})
         with pytest.raises(TAMRequiredError):
             key.unpack_and_verify_manifest(blob)
+        with pytest.raises(TAMRequiredError):
+            key.unpack_and_verify_archive(blob)
 
     def test_missing(self, key):
         blob = msgpack.packb({})
@@ -288,11 +285,16 @@ class TestTAM:
         unpacked, verified = key.unpack_and_verify_manifest(blob)
         assert unpacked == {}
         assert not verified
+        unpacked, verified, _ = key.unpack_and_verify_archive(blob)
+        assert unpacked == {}
+        assert not verified
 
     def test_unknown_type_when_required(self, key):
         blob = msgpack.packb({"tam": {"type": "HMAC_VOLLBIT"}})
         with pytest.raises(TAMUnsupportedSuiteError):
             key.unpack_and_verify_manifest(blob)
+        with pytest.raises(TAMUnsupportedSuiteError):
+            key.unpack_and_verify_archive(blob)
 
     def test_unknown_type(self, key):
         blob = msgpack.packb({"tam": {"type": "HMAC_VOLLBIT"}})
@@ -300,6 +302,9 @@ class TestTAM:
         unpacked, verified = key.unpack_and_verify_manifest(blob)
         assert unpacked == {}
         assert not verified
+        unpacked, verified, _ = key.unpack_and_verify_archive(blob)
+        assert unpacked == {}
+        assert not verified
 
     @pytest.mark.parametrize(
         "tam, exc",
@@ -310,11 +315,25 @@ class TestTAM:
             (1234, TAMInvalid),
         ),
     )
-    def test_invalid(self, key, tam, exc):
+    def test_invalid_manifest(self, key, tam, exc):
         blob = msgpack.packb({"tam": tam})
         with pytest.raises(exc):
             key.unpack_and_verify_manifest(blob)
 
+    @pytest.mark.parametrize(
+        "tam, exc",
+        (
+            ({}, TAMUnsupportedSuiteError),
+            ({"type": b"\xff"}, TAMUnsupportedSuiteError),
+            (None, ArchiveTAMInvalid),
+            (1234, ArchiveTAMInvalid),
+        ),
+    )
+    def test_invalid_archive(self, key, tam, exc):
+        blob = msgpack.packb({"tam": tam})
+        with pytest.raises(exc):
+            key.unpack_and_verify_archive(blob)
+
     @pytest.mark.parametrize(
         "hmac, salt",
         (({}, bytes(64)), (bytes(64), {}), (None, bytes(64)), (bytes(64), None)),
@@ -330,10 +349,12 @@ class TestTAM:
         blob = msgpack.packb(data)
         with pytest.raises(TAMInvalid):
             key.unpack_and_verify_manifest(blob)
+        with pytest.raises(ArchiveTAMInvalid):
+            key.unpack_and_verify_archive(blob)
 
-    def test_round_trip(self, key):
+    def test_round_trip_manifest(self, key):
         data = {"foo": "bar"}
-        blob = key.pack_and_authenticate_metadata(data)
+        blob = key.pack_and_authenticate_metadata(data, context=b"manifest")
         assert blob.startswith(b"\x82")
 
         unpacked = msgpack.unpackb(blob)
@@ -344,10 +365,23 @@ class TestTAM:
         assert unpacked["foo"] == "bar"
         assert "tam" not in unpacked
 
-    @pytest.mark.parametrize("which", ("hmac", "salt"))
+    def test_round_trip_archive(self, key):
-    def test_tampered(self, key, which):
         data = {"foo": "bar"}
-        blob = key.pack_and_authenticate_metadata(data)
+        blob = key.pack_and_authenticate_metadata(data, context=b"archive")
+        assert blob.startswith(b"\x82")
+
+        unpacked = msgpack.unpackb(blob)
+        assert unpacked["tam"]["type"] == "HKDF_HMAC_SHA512"
+
+        unpacked, verified, _ = key.unpack_and_verify_archive(blob)
+        assert verified
+        assert unpacked["foo"] == "bar"
+        assert "tam" not in unpacked
+
+    @pytest.mark.parametrize("which", ("hmac", "salt"))
+    def test_tampered_manifest(self, key, which):
+        data = {"foo": "bar"}
+        blob = key.pack_and_authenticate_metadata(data, context=b"manifest")
         assert blob.startswith(b"\x82")
 
         unpacked = msgpack.unpackb(blob, object_hook=StableDict)
@@ -359,6 +393,21 @@ class TestTAM:
         with pytest.raises(TAMInvalid):
             key.unpack_and_verify_manifest(blob)
 
+    @pytest.mark.parametrize("which", ("hmac", "salt"))
+    def test_tampered_archive(self, key, which):
+        data = {"foo": "bar"}
+        blob = key.pack_and_authenticate_metadata(data, context=b"archive")
+        assert blob.startswith(b"\x82")
+
+        unpacked = msgpack.unpackb(blob, object_hook=StableDict)
+        assert len(unpacked["tam"][which]) == 64
+        unpacked["tam"][which] = unpacked["tam"][which][0:32] + bytes(32)
+        assert len(unpacked["tam"][which]) == 64
+        blob = msgpack.packb(unpacked)
+
+        with pytest.raises(ArchiveTAMInvalid):
+            key.unpack_and_verify_archive(blob)
+
 
 def test_decrypt_key_file_unsupported_algorithm():
     """We will add more algorithms in the future. We should raise a helpful error."""