diff --git a/src/support/cleanse.h b/src/support/cleanse.h index 3e02aa8fd..f020216c7 100644 --- a/src/support/cleanse.h +++ b/src/support/cleanse.h @@ -8,6 +8,7 @@ #include +// Attempt to overwrite data in the specified memory span. void memory_cleanse(void *ptr, size_t len); #endif // BITCOIN_SUPPORT_CLEANSE_H diff --git a/src/wallet/db.h b/src/wallet/db.h index 1a46448cc..3c6870d16 100644 --- a/src/wallet/db.h +++ b/src/wallet/db.h @@ -180,22 +180,23 @@ public: Dbt datValue; datValue.set_flags(DB_DBT_MALLOC); int ret = pdb->get(activeTxn, &datKey, &datValue, 0); - memset(datKey.get_data(), 0, datKey.get_size()); - if (datValue.get_data() == NULL) - return false; - - // Unserialize value - try { - CDataStream ssValue((char*)datValue.get_data(), (char*)datValue.get_data() + datValue.get_size(), SER_DISK, CLIENT_VERSION); - ssValue >> value; - } catch (const std::exception&) { - return false; + memory_cleanse(datKey.get_data(), datKey.get_size()); + bool success = false; + if (datValue.get_data() != NULL) { + // Unserialize value + try { + CDataStream ssValue((char*)datValue.get_data(), (char*)datValue.get_data() + datValue.get_size(), SER_DISK, CLIENT_VERSION); + ssValue >> value; + success = true; + } catch (const std::exception&) { + // In this case success remains 'false' + } + + // Clear and free memory + memory_cleanse(datValue.get_data(), datValue.get_size()); + free(datValue.get_data()); } - - // Clear and free memory - memset(datValue.get_data(), 0, datValue.get_size()); - free(datValue.get_data()); - return (ret == 0); + return ret == 0 && success; } template @@ -222,8 +223,8 @@ public: int ret = pdb->put(activeTxn, &datKey, &datValue, (fOverwrite ? 0 : DB_NOOVERWRITE)); // Clear memory in case it was a private key - memset(datKey.get_data(), 0, datKey.get_size()); - memset(datValue.get_data(), 0, datValue.get_size()); + memory_cleanse(datKey.get_data(), datKey.get_size()); + memory_cleanse(datValue.get_data(), datValue.get_size()); return (ret == 0); } @@ -245,7 +246,7 @@ public: int ret = pdb->del(activeTxn, &datKey, 0); // Clear memory - memset(datKey.get_data(), 0, datKey.get_size()); + memory_cleanse(datKey.get_data(), datKey.get_size()); return (ret == 0 || ret == DB_NOTFOUND); } @@ -265,7 +266,7 @@ public: int ret = pdb->exists(activeTxn, &datKey, 0); // Clear memory - memset(datKey.get_data(), 0, datKey.get_size()); + memory_cleanse(datKey.get_data(), datKey.get_size()); return (ret == 0); } @@ -308,8 +309,8 @@ public: ssValue.write((char*)datValue.get_data(), datValue.get_size()); // Clear and free memory - memset(datKey.get_data(), 0, datKey.get_size()); - memset(datValue.get_data(), 0, datValue.get_size()); + memory_cleanse(datKey.get_data(), datKey.get_size()); + memory_cleanse(datValue.get_data(), datValue.get_size()); free(datKey.get_data()); free(datValue.get_data()); return 0;