Bug Fixes #

• darwin: skip synchronizable keychain queries when the data protection keychain is off (0606cb4)

• Fixed items written by versions prior to 0.3.0 becoming unreadable (and subsequent writes failing with errSecDuplicateItem) when no accessControlFlags are set. The 0.3.0 fix for kSecAttrSynchronizable being dropped caused read, readAll and containsKey to stop querying the legacy kSecAttrAccessControl storage envelope that those items were written under; they now fall back to it automatically. (#1158)

• Raised minimum iOS deployment target from 12.0 to 13.0 to fix Swift compiler errors when building with Swift Package Manager. CryptoKit (used for Secure Enclave support) requires iOS 13.0+.

• Fixed secStoreAvailabilitySink not being called when protected data availability changes.
• Fixed kSecUseDataProtectionKeychain being added to Keychain queries unconditionally; it is now only set when useDataProtectionKeychain is explicitly enabled.

• Fixed iOS build by updating availability annotation for Secure Enclave methods from iOS 11.3 to iOS 13.0.

• Added useSecureEnclave support for iOS and macOS to store encryption keys in the device's Secure Enclave for hardware-backed security.
• Use shared LAContext to reuse biometric authentication across Secure Enclave operations, avoiding double authentication prompts.
• Secure Enclave keys now use hardcoded .privateKeyUsage access control, preventing "ACL operation is not allowed" errors.

Fixes:

• Fixed kSecAttrSynchronizable being silently dropped when no access control flags are set.
• Fixed readAll to correctly return Secure Enclave items.
• Fixed macOS options keys alignment with iOS options.
• Added plain-text fallback when a Secure Enclave wrapped key is missing.

• Remove keys regardless of synchronizable state or accessibility constraints.

• Fix warnings with Privacy Manifest

This package combines flutter_secure_storage_macos together with the ios part of flutter_secure_storage.

Other changes:

• Code has been rebuild from the ground up
• Lots of missing attributes have been added to the IOSOptions and MacOsOptions classes.