wallet: make gap limit for change configurable
What the developer wrote
Authored by Filiprogrammer
wallet: make gap limit for change configurable
Add the ability to configure the gap limit for change addresses while
retaining that value in the wallet database.
----
extracted from https://github.com/spesmilo/electrum/pull/8726
Co-authored-by: SomberNight <somber.night@protonmail.com>
What changed, and why it matters
This commit adds a user-configurable setting for how many unused 'change' addresses Electrum keeps ready in a wallet, and stores that setting in the wallet file. It is a routine feature addition with no security relevance visible in the code or commit message.
No security action needed; review as normal feature code.
Security signals we found
No strong security signals were identified.
Evidence from the diff
The change moves gap_limit_for_change from a class-level constant in Abstract_Wallet to a per-wallet instance variable in Deterministic_Wallet, initialized from the wallet database with a default of 10. It also threads a new gap_limit_for_change parameter through create_new_wallet() and restore_wallet_from_text() so the value can be persisted at wallet creation/restoration. No logic affecting key handling, cryptography, network communication, or transaction signing is modified.
Changed components
electrum/wallet.pyInspect captured patch +8 / −2
diff --git a/electrum/wallet.py b/electrum/wallet.py
index 20a3f8f..4102fd7 100644
--- a/electrum/wallet.py
+++ b/electrum/wallet.py
@@ -391,7 +391,6 @@ class Abstract_Wallet(ABC, Logger, EventListener):
"""
max_change_outputs = 3
- gap_limit_for_change = 10
txin_type: str
wallet_type: str
@@ -3814,6 +3813,7 @@ class Deterministic_Wallet(Abstract_Wallet):
self._ephemeral_addr_to_addr_index = {} # type: Dict[str, Sequence[int]]
Abstract_Wallet.__init__(self, db, config=config)
self.gap_limit = db.get('gap_limit', 20)
+ self.gap_limit_for_change = db.get('gap_limit_for_change', 10)
# generate addresses now. note that without libsecp this might block
# for a few seconds!
self.synchronize()
@@ -4232,7 +4232,8 @@ def create_new_wallet(
password: Optional[str] = None,
encrypt_file: bool = True,
seed_type: Optional[str] = None,
- gap_limit: Optional[int] = None
+ gap_limit: Optional[int] = None,
+ gap_limit_for_change: Optional[int] = None,
) -> dict:
"""Create a new wallet"""
storage = WalletStorage(path, allow_partial_writes=config.WALLET_PARTIAL_WRITES)
@@ -4248,6 +4249,8 @@ def create_new_wallet(
db.put('lightning_xprv', k.get_lightning_xprv(None))
if gap_limit is not None:
db.put('gap_limit', gap_limit)
+ if gap_limit_for_change is not None:
+ db.put('gap_limit_for_change', gap_limit_for_change)
wallet = Wallet(db, config=config)
wallet.update_password(old_pw=None, new_pw=password, encrypt_storage=encrypt_file)
wallet.synchronize()
@@ -4265,6 +4268,7 @@ def restore_wallet_from_text(
password: Optional[str] = None,
encrypt_file: Optional[bool] = None,
gap_limit: Optional[int] = None,
+ gap_limit_for_change: Optional[int] = None,
) -> dict:
"""Restore a wallet from text. Text can be a seed phrase, a master
public key, a master private key, a list of bitcoin addresses
@@ -4308,6 +4312,8 @@ def restore_wallet_from_text(
db.put('wallet_type', 'standard')
if gap_limit is not None:
db.put('gap_limit', gap_limit)
+ if gap_limit_for_change is not None:
+ db.put('gap_limit_for_change', gap_limit_for_change)
wallet = Wallet(db, config=config)
if db.storage:
assert not db.storage.file_exists(), "file was created too soon! plaintext keys might have been written to disk"
Why this scored 15/100
Community notes
Notes can correct, qualify, or add evidence to the AI analysis. Every note shown here has been validated by a human moderator.
The AI analysis stands alone for now. Submit a note if you can add evidence or important context.