tahoe-lafs/docs/specifications/derive_renewal_secret.py

88 lines
3.1 KiB
Python

"""
This is a reference implementation of the lease renewal secret derivation
protocol in use by Tahoe-LAFS clients as of 1.16.0.
"""
from allmydata.util.base32 import (
a2b as b32decode,
b2a as b32encode,
)
from allmydata.util.hashutil import (
tagged_hash,
tagged_pair_hash,
)
def derive_renewal_secret(lease_secret: bytes, storage_index: bytes, tubid: bytes) -> bytes:
assert len(lease_secret) == 32
assert len(storage_index) == 16
assert len(tubid) == 20
bucket_renewal_tag = b"allmydata_bucket_renewal_secret_v1"
file_renewal_tag = b"allmydata_file_renewal_secret_v1"
client_renewal_tag = b"allmydata_client_renewal_secret_v1"
client_renewal_secret = tagged_hash(lease_secret, client_renewal_tag)
file_renewal_secret = tagged_pair_hash(
file_renewal_tag,
client_renewal_secret,
storage_index,
)
peer_id = tubid
return tagged_pair_hash(bucket_renewal_tag, file_renewal_secret, peer_id)
def demo():
secret = b32encode(derive_renewal_secret(
b"lease secretxxxxxxxxxxxxxxxxxxxx",
b"storage indexxxx",
b"tub idxxxxxxxxxxxxxx",
)).decode("ascii")
print("An example renewal secret: {}".format(secret))
def test():
# These test vectors created by intrumenting Tahoe-LAFS
# bb57fcfb50d4e01bbc4de2e23dbbf7a60c004031 to emit `self.renew_secret` in
# allmydata.immutable.upload.ServerTracker.query and then uploading a
# couple files to a couple different storage servers.
test_vector = [
dict(lease_secret=b"boity2cdh7jvl3ltaeebuiobbspjmbuopnwbde2yeh4k6x7jioga",
storage_index=b"vrttmwlicrzbt7gh5qsooogr7u",
tubid=b"v67jiisoty6ooyxlql5fuucitqiok2ic",
expected=b"osd6wmc5vz4g3ukg64sitmzlfiaaordutrez7oxdp5kkze7zp5zq",
),
dict(lease_secret=b"boity2cdh7jvl3ltaeebuiobbspjmbuopnwbde2yeh4k6x7jioga",
storage_index=b"75gmmfts772ww4beiewc234o5e",
tubid=b"v67jiisoty6ooyxlql5fuucitqiok2ic",
expected=b"35itmusj7qm2pfimh62snbyxp3imreofhx4djr7i2fweta75szda",
),
dict(lease_secret=b"boity2cdh7jvl3ltaeebuiobbspjmbuopnwbde2yeh4k6x7jioga",
storage_index=b"75gmmfts772ww4beiewc234o5e",
tubid=b"lh5fhobkjrmkqjmkxhy3yaonoociggpz",
expected=b"srrlruge47ws3lm53vgdxprgqb6bz7cdblnuovdgtfkqrygrjm4q",
),
dict(lease_secret=b"vacviff4xfqxsbp64tdr3frg3xnkcsuwt5jpyat2qxcm44bwu75a",
storage_index=b"75gmmfts772ww4beiewc234o5e",
tubid=b"lh5fhobkjrmkqjmkxhy3yaonoociggpz",
expected=b"b4jledjiqjqekbm2erekzqumqzblegxi23i5ojva7g7xmqqnl5pq",
),
]
for n, item in enumerate(test_vector):
derived = b32encode(derive_renewal_secret(
b32decode(item["lease_secret"]),
b32decode(item["storage_index"]),
b32decode(item["tubid"]),
))
assert derived == item["expected"] , \
"Test vector {} failed: {} (expected) != {} (derived)".format(
n,
item["expected"],
derived,
)
print("{} test vectors validated".format(len(test_vector)))
test()
demo()