remove nonce management, related repo methods

src/borg/crypto/key.py

@@ -25,7 +25,6 @@
 from ..repoobj import RepoObj
 
 
-from .nonces import NonceManager
 from .low_level import AES, bytes_to_int, num_cipher_blocks, hmac_sha256, blake2b_256, hkdf_hmac_sha512
 from .low_level import AES256_CTR_HMAC_SHA256, AES256_CTR_BLAKE2b, AES256_OCB, CHACHA20_POLY1305
 from . import low_level
@@ -372,7 +371,8 @@ class AESKeyBase(KeyBase):
     logically_encrypted = True
 
     def encrypt(self, id, data):
-        next_iv = self.nonce_manager.ensure_reservation(self.cipher.next_iv(), self.cipher.block_count(len(data)))
+        # legacy, this is only used by the tests.
+        next_iv = self.cipher.next_iv()
         return self.cipher.encrypt(data, header=self.TYPE_STR, iv=next_iv)
 
     def decrypt(self, id, data):
@@ -411,7 +411,6 @@ def init_ciphers(self, manifest_data=None):
             manifest_blocks = num_cipher_blocks(len(manifest_data))
             nonce = self.cipher.extract_iv(manifest_data) + manifest_blocks
         self.cipher.set_iv(nonce)
-        self.nonce_manager = NonceManager(self.repository, nonce)
 
 
 class FlexiKey:

src/borg/remote.py

@@ -134,8 +134,6 @@ def __init__(self, data):
     "negotiate": ("client_data",),
     "open": ("path", "create", "lock_wait", "lock", "exclusive", "append_only"),
     "info": (),
-    "get_free_nonce": (),
-    "commit_nonce_reservation": ("next_unreserved", "start_nonce"),
 }
 
 
@@ -159,8 +157,6 @@ class RepositoryServer:  # pragma: no cover
         "save_key",
         "load_key",
         "break_lock",
-        "get_free_nonce",
-        "commit_nonce_reservation",
         "inject_exception",
     )
 
@@ -1024,14 +1020,6 @@ def save_key(self, keydata):
     def load_key(self):
         """actual remoting is done via self.call in the @api decorator"""
 
-    @api(since=parse_version("1.0.0"))
-    def get_free_nonce(self):
-        """actual remoting is done via self.call in the @api decorator"""
-
-    @api(since=parse_version("1.0.0"))
-    def commit_nonce_reservation(self, next_unreserved, start_nonce):
-        """actual remoting is done via self.call in the @api decorator"""
-
     @api(since=parse_version("1.0.0"))
     def break_lock(self):
         """actual remoting is done via self.call in the @api decorator"""

src/borg/repository.py

@@ -369,36 +369,6 @@ def load_key(self):
         # note: if we return an empty string, it means there is no repo key
         return keydata.encode("utf-8")  # remote repo: msgpack issue #99, returning bytes
 
-    def get_free_nonce(self):
-        if self.do_lock and not self.lock.got_exclusive_lock():
-            raise AssertionError("bug in code, exclusive lock should exist here")
-
-        nonce_path = os.path.join(self.path, "nonce")
-        try:
-            with open(nonce_path) as fd:
-                return int.from_bytes(unhexlify(fd.read()), byteorder="big")
-        except FileNotFoundError:
-            return None
-
-    def commit_nonce_reservation(self, next_unreserved, start_nonce):
-        if self.do_lock and not self.lock.got_exclusive_lock():
-            raise AssertionError("bug in code, exclusive lock should exist here")
-
-        if self.get_free_nonce() != start_nonce:
-            raise Exception("nonce space reservation with mismatched previous state")
-        nonce_path = os.path.join(self.path, "nonce")
-        try:
-            with SaveFile(nonce_path, binary=False) as fd:
-                fd.write(bin_to_hex(next_unreserved.to_bytes(8, byteorder="big")))
-        except PermissionError as e:
-            # error is only a problem if we even had a lock
-            if self.do_lock:
-                raise
-            logger.warning(
-                "%s: Failed writing to '%s'. This is expected when working on "
-                "read-only repositories." % (e.strerror, e.filename)
-            )
-
     def destroy(self):
         """Destroy the repository at `self.path`"""
         if self.append_only:

src/borg/testsuite/key.py

@@ -116,12 +116,6 @@ def canonical_path(self):
         id = bytes(32)
         id_str = bin_to_hex(id)
 
-        def get_free_nonce(self):
-            return None
-
-        def commit_nonce_reservation(self, next_unreserved, start_nonce):
-            pass
-
         def save_key(self, data):
             self.key_data = data