DragonX/dragonx
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases 4 Wiki Activity

wallet: erase the plaintext HD seed record when the wallet is encrypted

Browse Source 
CWalletDB::WriteCryptedHDSeed wrote the "chdseed" record and left "hdseed" in
place, unlike WriteCryptedKey which erases "key"/"wkey" after writing "ckey".
No erase of "hdseed" existed anywhere in src/wallet/.

CDB::Rewrite does not save us: EncryptWallet calls it with pszSkip defaulted, so
it copies every surviving record verbatim into the new file. The result is that a
wallet created unencrypted and later encrypted keeps its raw HD seed in cleartext
on disk permanently, and reloads it into memory on every start.

Add CWalletDB::EraseHDSeed and call it from CWallet::SetCryptedHDSeed after the
encrypted record is written, through the same CWalletDB so it shares
EncryptWallet's transaction. Erase returns true on DB_NOTFOUND, so a wallet that
was never written in plaintext is unaffected.

The erase is deliberately best-effort and only logs on failure. A hard failure
here propagates into CCryptoKeyStore::EncryptKeys, which EncryptWallet turns into
assert(false) with half the keys encrypted in memory; a warning is strictly
better than that.

Note this path is only reachable with -developerencryptwallet, which is
experimental and off by default on this chain, so this is a latent fix rather
than a live one.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
This commit is contained in:
DanS
2026-08-23 06:14:31 +02:00
co-authored by Claude Opus 5
parent e2f88175ab
commit 143c33de48
3 changed files with 42 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/wallet/wallet.cpp
+27 -4
View File
@@ -2523,10 +2523,33 @@ bool CWallet::SetCryptedHDSeed(const uint256& seedFp, const std::vector<unsigned
{
LOCK(cs_wallet);
if (pwalletdbEncryption)
return pwalletdbEncryption->WriteCryptedHDSeed(seedFp, vchCryptedSecret);
else
return CWalletDB(strWalletFile).WriteCryptedHDSeed(seedFp, vchCryptedSecret);
// Write the encrypted record, then drop the plaintext one. Both go
// through the same CWalletDB (and therefore the same transaction when
// EncryptWallet supplied pwalletdbEncryption), because CDB::Rewrite at
// the end of EncryptWallet copies every surviving record into the fresh
// file -- a leftover plaintext "hdseed" would keep the unencrypted seed
// on disk for the life of the wallet.
//
// The erase is deliberately best-effort: a hard failure here propagates
// into CCryptoKeyStore::EncryptKeys, which CWallet::EncryptWallet turns
// into assert(false) with half the keys encrypted in memory. A logged
// warning is strictly better than that.
if (pwalletdbEncryption) {
if (!pwalletdbEncryption->WriteCryptedHDSeed(seedFp, vchCryptedSecret))
return false;
if (!pwalletdbEncryption->EraseHDSeed(seedFp))
LogPrintf("%s: WARNING: could not erase the plaintext hdseed record; "
"the unencrypted HD seed may remain in wallet.dat\n", __func__);
return true;
} else {
CWalletDB walletdb(strWalletFile);
if (!walletdb.WriteCryptedHDSeed(seedFp, vchCryptedSecret))
return false;
if (!walletdb.EraseHDSeed(seedFp))
LogPrintf("%s: WARNING: could not erase the plaintext hdseed record; "
"the unencrypted HD seed may remain in wallet.dat\n", __func__);
return true;
}
}
return false;
}