From: david-sarah Date: Tue, 2 Aug 2011 17:58:41 +0000 (-0700) Subject: test_repairer: add a deterministic test of share data corruption that always flips... X-Git-Url: https://git.rkrishnan.org/?a=commitdiff_plain;h=9f8d34e63aa1aeeb5dbe3bd3b6e0548db2cecf1b;p=tahoe-lafs%2Ftahoe-lafs.git test_repairer: add a deterministic test of share data corruption that always flips the bits of the last byte of the share data. refs #1395 --- diff --git a/src/allmydata/test/common.py b/src/allmydata/test/common.py index f61e5dde..b1050919 100644 --- a/src/allmydata/test/common.py +++ b/src/allmydata/test/common.py @@ -1200,6 +1200,22 @@ def _corrupt_share_data(data, debug=False): return corrupt_field(data, 0x0c+0x44, sharedatasize) +def _corrupt_share_data_last_byte(data, debug=False): + """Scramble the file data -- flip all bits of the last byte.""" + sharevernum = struct.unpack(">L", data[0x0c:0x0c+4])[0] + assert sharevernum in (1, 2), "This test is designed to corrupt immutable shares of v1 or v2 in specific ways, not v%d." % sharevernum + if sharevernum == 1: + sharedatasize = struct.unpack(">L", data[0x0c+0x08:0x0c+0x08+4])[0] + offset = 0x0c+0x24+sharedatasize-1 + else: + sharedatasize = struct.unpack(">Q", data[0x0c+0x08:0x0c+0x0c+8])[0] + offset = 0x0c+0x44+sharedatasize-1 + + newdata = data[:offset] + chr(ord(data[offset])^0xFF) + data[offset+1:] + if debug: + log.msg("testing: flipping all bits of byte at offset %d: %r, newdata: %r" % (offset, data[offset], newdata[offset])) + return newdata + def _corrupt_crypttext_hash_tree(data, debug=False): """Scramble the file data -- the field containing the crypttext hash tree will have one bit flipped or else will be changed to a random value. diff --git a/src/allmydata/test/test_repairer.py b/src/allmydata/test/test_repairer.py index 7efb4a82..94cd9ee4 100644 --- a/src/allmydata/test/test_repairer.py +++ b/src/allmydata/test/test_repairer.py @@ -239,6 +239,11 @@ class Verifier(GridTestMixin, unittest.TestCase, RepairTestMixin): return self._help_test_verify(common._corrupt_share_data, self.judge_invisible_corruption) + def test_corrupt_sharedata_last_byte(self): + self.basedir = "repairer/Verifier/corrupt_sharedata_last_byte" + return self._help_test_verify(common._corrupt_share_data_last_byte, + self.judge_invisible_corruption) + def test_corrupt_ueb_length(self): self.basedir = "repairer/Verifier/corrupt_ueb_length" return self._help_test_verify(common._corrupt_length_of_uri_extension,