Merge "Keystore 2.0: Teach keystore to decrypt generic blobs."
diff --git a/keystore2/legacykeystore/lib.rs b/keystore2/legacykeystore/lib.rs
index 13a9143..e2d952d 100644
--- a/keystore2/legacykeystore/lib.rs
+++ b/keystore2/legacykeystore/lib.rs
@@ -25,8 +25,9 @@
 };
 use anyhow::{Context, Result};
 use keystore2::{
-    async_task::AsyncTask, error::anyhow_error_to_cstring, legacy_blob::LegacyBlobLoader,
-    maintenance::DeleteListener, maintenance::Domain, utils::watchdog as wd,
+    async_task::AsyncTask, error::anyhow_error_to_cstring, globals::SUPER_KEY,
+    legacy_blob::LegacyBlobLoader, maintenance::DeleteListener, maintenance::Domain,
+    utils::uid_to_android_user, utils::watchdog as wd,
 };
 use rusqlite::{
     params, Connection, OptionalExtension, Transaction, TransactionBehavior, NO_PARAMS,
@@ -315,8 +316,8 @@
         if let Some(entry) = db.get(uid, alias).context("In get: Trying to load entry from DB.")? {
             return Ok(entry);
         }
-        if self.get_legacy(uid, alias).context("In get: Trying to migrate legacy blob.")? {
-            // If we were able to migrate a legacy blob try again.
+        if self.get_legacy(uid, alias).context("In get: Trying to import legacy blob.")? {
+            // If we were able to import a legacy blob try again.
             if let Some(entry) =
                 db.get(uid, alias).context("In get: Trying to load entry from DB.")?
             {
@@ -328,19 +329,20 @@
 
     fn put(&self, alias: &str, uid: i32, entry: &[u8]) -> Result<()> {
         let uid = Self::get_effective_uid(uid).context("In put.")?;
-        // In order to make sure that we don't have stale legacy entries, make sure they are
-        // migrated before replacing them.
-        let _ = self.get_legacy(uid, alias);
         let mut db = self.open_db().context("In put.")?;
-        db.put(uid, alias, entry).context("In put: Trying to insert entry into DB.")
+        db.put(uid, alias, entry).context("In put: Trying to insert entry into DB.")?;
+        // When replacing an entry, make sure that there is no stale legacy file entry.
+        let _ = self.remove_legacy(uid, alias);
+        Ok(())
     }
 
     fn remove(&self, alias: &str, uid: i32) -> Result<()> {
         let uid = Self::get_effective_uid(uid).context("In remove.")?;
         let mut db = self.open_db().context("In remove.")?;
-        // In order to make sure that we don't have stale legacy entries, make sure they are
-        // migrated before removing them.
-        let _ = self.get_legacy(uid, alias);
+
+        if self.remove_legacy(uid, alias).context("In remove: trying to remove legacy entry")? {
+            return Ok(());
+        }
         let removed =
             db.remove(uid, alias).context("In remove: Trying to remove entry from DB.")?;
         if removed {
@@ -430,17 +432,30 @@
                 return Ok(true);
             }
             let mut db = DB::new(&state.db_path).context("In open_db: Failed to open db.")?;
-            let migrated =
-                Self::migrate_one_legacy_entry(uid, &alias, &state.legacy_loader, &mut db)
-                    .context("Trying to migrate legacy keystore entries.")?;
-            if migrated {
+            let imported =
+                Self::import_one_legacy_entry(uid, &alias, &state.legacy_loader, &mut db)
+                    .context("Trying to import legacy keystore entries.")?;
+            if imported {
                 state.recently_imported.insert((uid, alias));
             }
-            Ok(migrated)
+            Ok(imported)
         })
         .context("In get_legacy.")
     }
 
+    fn remove_legacy(&self, uid: u32, alias: &str) -> Result<bool> {
+        let alias = alias.to_string();
+        self.do_serialized(move |state| {
+            if state.recently_imported.contains(&(uid, alias.clone())) {
+                return Ok(false);
+            }
+            state
+                .legacy_loader
+                .remove_legacy_keystore_entry(uid, &alias)
+                .context("Trying to remove legacy entry.")
+        })
+    }
+
     fn bulk_delete_uid(&self, uid: u32) -> Result<()> {
         self.do_serialized(move |state| {
             let entries = state
@@ -473,21 +488,31 @@
         })
     }
 
-    fn migrate_one_legacy_entry(
+    fn import_one_legacy_entry(
         uid: u32,
         alias: &str,
         legacy_loader: &LegacyBlobLoader,
         db: &mut DB,
     ) -> Result<bool> {
         let blob = legacy_loader
-            .read_legacy_keystore_entry(uid, alias)
-            .context("In migrate_one_legacy_entry: Trying to read legacy keystore entry.")?;
+            .read_legacy_keystore_entry(uid, alias, |ciphertext, iv, tag, _salt, _key_size| {
+                if let Some(key) = SUPER_KEY
+                    .read()
+                    .unwrap()
+                    .get_per_boot_key_by_user_id(uid_to_android_user(uid as u32))
+                {
+                    key.decrypt(ciphertext, iv, tag)
+                } else {
+                    Err(Error::sys()).context("No key found for user. Device may be locked.")
+                }
+            })
+            .context("In import_one_legacy_entry: Trying to read legacy keystore entry.")?;
         if let Some(entry) = blob {
             db.put(uid, alias, &entry)
-                .context("In migrate_one_legacy_entry: Trying to insert entry into DB.")?;
+                .context("In import_one_legacy_entry: Trying to insert entry into DB.")?;
             legacy_loader
                 .remove_legacy_keystore_entry(uid, alias)
-                .context("In migrate_one_legacy_entry: Trying to delete legacy keystore entry.")?;
+                .context("In import_one_legacy_entry: Trying to delete legacy keystore entry.")?;
             Ok(true)
         } else {
             Ok(false)
diff --git a/keystore2/src/database.rs b/keystore2/src/database.rs
index e68b0fd..65ee7ae 100644
--- a/keystore2/src/database.rs
+++ b/keystore2/src/database.rs
@@ -578,6 +578,36 @@
     cert_chain: Option<Vec<u8>>,
 }
 
+/// This type represents a Blob with its metadata and an optional superseded blob.
+#[derive(Debug)]
+pub struct BlobInfo<'a> {
+    blob: &'a [u8],
+    metadata: &'a BlobMetaData,
+    /// Superseded blobs are an artifact of legacy import. In some rare occasions
+    /// the key blob needs to be upgraded during import. In that case two
+    /// blob are imported, the superseded one will have to be imported first,
+    /// so that the garbage collector can reap it.
+    superseded_blob: Option<(&'a [u8], &'a BlobMetaData)>,
+}
+
+impl<'a> BlobInfo<'a> {
+    /// Create a new instance of blob info with blob and corresponding metadata
+    /// and no superseded blob info.
+    pub fn new(blob: &'a [u8], metadata: &'a BlobMetaData) -> Self {
+        Self { blob, metadata, superseded_blob: None }
+    }
+
+    /// Create a new instance of blob info with blob and corresponding metadata
+    /// as well as superseded blob info.
+    pub fn new_with_superseded(
+        blob: &'a [u8],
+        metadata: &'a BlobMetaData,
+        superseded_blob: Option<(&'a [u8], &'a BlobMetaData)>,
+    ) -> Self {
+        Self { blob, metadata, superseded_blob }
+    }
+}
+
 impl CertificateInfo {
     /// Constructs a new CertificateInfo object from `cert` and `cert_chain`
     pub fn new(cert: Option<Vec<u8>>, cert_chain: Option<Vec<u8>>) -> Self {
@@ -2233,7 +2263,7 @@
         key: &KeyDescriptor,
         key_type: KeyType,
         params: &[KeyParameter],
-        blob_info: &(&[u8], &BlobMetaData),
+        blob_info: &BlobInfo,
         cert_info: &CertificateInfo,
         metadata: &KeyMetaData,
         km_uuid: &Uuid,
@@ -2253,7 +2283,27 @@
         self.with_transaction(TransactionBehavior::Immediate, |tx| {
             let key_id = Self::create_key_entry_internal(tx, &domain, namespace, key_type, km_uuid)
                 .context("Trying to create new key entry.")?;
-            let (blob, blob_metadata) = *blob_info;
+            let BlobInfo { blob, metadata: blob_metadata, superseded_blob } = *blob_info;
+
+            // In some occasions the key blob is already upgraded during the import.
+            // In order to make sure it gets properly deleted it is inserted into the
+            // database here and then immediately replaced by the superseding blob.
+            // The garbage collector will then subject the blob to deleteKey of the
+            // KM back end to permanently invalidate the key.
+            let need_gc = if let Some((blob, blob_metadata)) = superseded_blob {
+                Self::set_blob_internal(
+                    tx,
+                    key_id.id(),
+                    SubComponentType::KEY_BLOB,
+                    Some(blob),
+                    Some(blob_metadata),
+                )
+                .context("Trying to insert superseded key blob.")?;
+                true
+            } else {
+                false
+            };
+
             Self::set_blob_internal(
                 tx,
                 key_id.id(),
@@ -2280,7 +2330,8 @@
                 .context("Trying to insert key parameters.")?;
             metadata.store_in_db(key_id.id(), tx).context("Trying to insert key metadata.")?;
             let need_gc = Self::rebind_alias(tx, &key_id, alias, &domain, namespace, key_type)
-                .context("Trying to rebind alias.")?;
+                .context("Trying to rebind alias.")?
+                || need_gc;
             Ok(key_id).do_gc(need_gc)
         })
         .context("In store_new_key.")
@@ -3234,6 +3285,7 @@
     use std::sync::{Arc, RwLock};
     use std::thread;
     use std::time::{Duration, SystemTime};
+    use crate::utils::AesGcm;
     #[cfg(disabled)]
     use std::time::Instant;
 
@@ -5557,8 +5609,7 @@
             None,
         )?;
 
-        let decrypted_secret_bytes =
-            loaded_super_key.aes_gcm_decrypt(&encrypted_secret, &iv, &tag)?;
+        let decrypted_secret_bytes = loaded_super_key.decrypt(&encrypted_secret, &iv, &tag)?;
         assert_eq!(secret_bytes, &*decrypted_secret_bytes);
 
         Ok(())
diff --git a/keystore2/src/legacy_blob.rs b/keystore2/src/legacy_blob.rs
index b801ed3..cbc680d 100644
--- a/keystore2/src/legacy_blob.rs
+++ b/keystore2/src/legacy_blob.rs
@@ -17,8 +17,8 @@
 use crate::{
     error::{Error as KsError, ResponseCode},
     key_parameter::{KeyParameter, KeyParameterValue},
-    super_key::SuperKeyManager,
     utils::uid_to_android_user,
+    utils::AesGcm,
 };
 use android_hardware_security_keymint::aidl::android::hardware::security::keymint::{
     SecurityLevel::SecurityLevel, Tag::Tag, TagType::TagType,
@@ -26,6 +26,7 @@
 use anyhow::{Context, Result};
 use keystore2_crypto::{aes_gcm_decrypt, Password, ZVec};
 use std::collections::{HashMap, HashSet};
+use std::sync::Arc;
 use std::{convert::TryInto, fs::File, path::Path, path::PathBuf};
 use std::{
     fs,
@@ -87,6 +88,14 @@
     /// an invalid alias filename encoding.
     #[error("Invalid alias filename encoding.")]
     BadEncoding,
+    /// A component of the requested entry other than the KM key blob itself
+    /// was encrypted and no super key was provided.
+    #[error("Locked entry component.")]
+    LockedComponent,
+    /// The uids presented to move_keystore_entry belonged to different
+    /// Android users.
+    #[error("Cannot move keys across Android users.")]
+    AndroidUserMismatch,
 }
 
 /// The blob payload, optionally with all information required to decrypt it.
@@ -96,6 +105,16 @@
     Generic(Vec<u8>),
     /// A legacy key characteristics file. This has only a single list of Authorizations.
     Characteristics(Vec<u8>),
+    /// A legacy key characteristics file. This has only a single list of Authorizations.
+    /// Additionally, this characteristics file was encrypted with the user's super key.
+    EncryptedCharacteristics {
+        /// Initialization vector.
+        iv: Vec<u8>,
+        /// Aead tag for integrity verification.
+        tag: Vec<u8>,
+        /// Ciphertext.
+        data: Vec<u8>,
+    },
     /// A key characteristics cache has both a hardware enforced and a software enforced list
     /// of authorizations.
     CharacteristicsCache(Vec<u8>),
@@ -124,6 +143,17 @@
         /// Ciphertext.
         data: Vec<u8>,
     },
+    /// An encrypted blob. Includes the initialization vector, the aead tag, and the
+    /// ciphertext data. The key can be selected from context, i.e., the owner of the key
+    /// blob. This is a special case for generic encrypted blobs as opposed to key blobs.
+    EncryptedGeneric {
+        /// Initialization vector.
+        iv: Vec<u8>,
+        /// Aead tag for integrity verification.
+        tag: Vec<u8>,
+        /// Ciphertext.
+        data: Vec<u8>,
+    },
     /// Holds the plaintext key blob either after unwrapping an encrypted blob or when the
     /// blob was stored in "plaintext" on disk. The "plaintext" of a key blob is not actual
     /// plaintext because all KeyMint blobs are encrypted with a device bound key. The key
@@ -132,6 +162,19 @@
     Decrypted(ZVec),
 }
 
+/// Keystore used two different key characteristics file formats in the past.
+/// The key characteristics cache which superseded the characteristics file.
+/// The latter stored only one list of key parameters, while the former stored
+/// a hardware enforced and a software enforced list. This Enum indicates which
+/// type was read from the file system.
+#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd)]
+pub enum LegacyKeyCharacteristics {
+    /// A characteristics cache was read.
+    Cache(Vec<KeyParameter>),
+    /// A characteristics file was read.
+    File(Vec<KeyParameter>),
+}
+
 /// Represents a loaded legacy key blob file.
 #[derive(Debug, Eq, PartialEq)]
 pub struct Blob {
@@ -169,6 +212,16 @@
 }
 
 impl Blob {
+    /// Creates a new blob from flags and value.
+    pub fn new(flags: u8, value: BlobValue) -> Self {
+        Self { flags, value }
+    }
+
+    /// Return the raw flags of this Blob.
+    pub fn get_flags(&self) -> u8 {
+        self.flags
+    }
+
     /// This blob was generated with a fallback software KM device.
     pub fn is_fallback(&self) -> bool {
         self.flags & flags::FALLBACK != 0
@@ -212,10 +265,14 @@
     // version (1 Byte)
     // blob_type (1 Byte)
     // flags (1 Byte)
-    // info (1 Byte)
+    // info (1 Byte) Size of an info field appended to the blob.
     // initialization_vector (16 Bytes)
     // integrity (MD5 digest or gcm tag) (16 Bytes)
     // length (4 Bytes)
+    //
+    // The info field is used to store the salt for password encrypted blobs.
+    // The beginning of the info field can be computed from the file length
+    // and the info byte from the header: <file length> - <info> bytes.
     const COMMON_HEADER_SIZE: usize = 4 + Self::IV_SIZE + Self::GCM_TAG_LENGTH + 4;
 
     const VERSION_OFFSET: usize = 0;
@@ -341,12 +398,28 @@
         let tag = &buffer[Self::AEAD_TAG_OFFSET..Self::AEAD_TAG_OFFSET + Self::GCM_TAG_LENGTH];
 
         match (blob_type, is_encrypted, salt) {
-            (blob_types::GENERIC, _, _) => {
+            (blob_types::GENERIC, false, _) => {
                 Ok(Blob { flags, value: BlobValue::Generic(value.to_vec()) })
             }
-            (blob_types::KEY_CHARACTERISTICS, _, _) => {
+            (blob_types::GENERIC, true, _) => Ok(Blob {
+                flags,
+                value: BlobValue::EncryptedGeneric {
+                    iv: iv.to_vec(),
+                    tag: tag.to_vec(),
+                    data: value.to_vec(),
+                },
+            }),
+            (blob_types::KEY_CHARACTERISTICS, false, _) => {
                 Ok(Blob { flags, value: BlobValue::Characteristics(value.to_vec()) })
             }
+            (blob_types::KEY_CHARACTERISTICS, true, _) => Ok(Blob {
+                flags,
+                value: BlobValue::EncryptedCharacteristics {
+                    iv: iv.to_vec(),
+                    tag: tag.to_vec(),
+                    data: value.to_vec(),
+                },
+            }),
             (blob_types::KEY_CHARACTERISTICS_CACHE, _, _) => {
                 Ok(Blob { flags, value: BlobValue::CharacteristicsCache(value.to_vec()) })
             }
@@ -427,6 +500,15 @@
                         .context("In new_from_stream_decrypt_with.")?,
                 ),
             }),
+            BlobValue::EncryptedGeneric { iv, tag, data } => Ok(Blob {
+                flags: blob.flags,
+                value: BlobValue::Generic(
+                    decrypt(data, iv, tag, None, None)
+                        .context("In new_from_stream_decrypt_with.")?[..]
+                        .to_vec(),
+                ),
+            }),
+
             _ => Ok(blob),
         }
     }
@@ -546,24 +628,91 @@
         Ok(params)
     }
 
+    /// This function takes a Blob and an optional AesGcm. Plain text blob variants are
+    /// passed through as is. If a super key is given an attempt is made to decrypt the
+    /// blob thereby mapping BlobValue variants as follows:
+    /// BlobValue::Encrypted => BlobValue::Decrypted
+    /// BlobValue::EncryptedGeneric => BlobValue::Generic
+    /// BlobValue::EncryptedCharacteristics => BlobValue::Characteristics
+    /// If now super key is given or BlobValue::PwEncrypted is encountered,
+    /// Err(Error::LockedComponent) is returned.
+    fn decrypt_if_required(super_key: &Option<Arc<dyn AesGcm>>, blob: Blob) -> Result<Blob> {
+        match blob {
+            Blob { value: BlobValue::Generic(_), .. }
+            | Blob { value: BlobValue::Characteristics(_), .. }
+            | Blob { value: BlobValue::CharacteristicsCache(_), .. }
+            | Blob { value: BlobValue::Decrypted(_), .. } => Ok(blob),
+            Blob { value: BlobValue::EncryptedCharacteristics { iv, tag, data }, flags }
+                if super_key.is_some() =>
+            {
+                Ok(Blob {
+                    value: BlobValue::Characteristics(
+                        super_key.as_ref().unwrap().decrypt(&data, &iv, &tag).context(
+                            "In decrypt_if_required: Failed to decrypt EncryptedCharacteristics",
+                        )?[..]
+                            .to_vec(),
+                    ),
+                    flags,
+                })
+            }
+            Blob { value: BlobValue::Encrypted { iv, tag, data }, flags }
+                if super_key.is_some() =>
+            {
+                Ok(Blob {
+                    value: BlobValue::Decrypted(
+                        super_key
+                            .as_ref()
+                            .unwrap()
+                            .decrypt(&data, &iv, &tag)
+                            .context("In decrypt_if_required: Failed to decrypt Encrypted")?,
+                    ),
+                    flags,
+                })
+            }
+            Blob { value: BlobValue::EncryptedGeneric { iv, tag, data }, flags }
+                if super_key.is_some() =>
+            {
+                Ok(Blob {
+                    value: BlobValue::Generic(
+                        super_key
+                            .as_ref()
+                            .unwrap()
+                            .decrypt(&data, &iv, &tag)
+                            .context("In decrypt_if_required: Failed to decrypt Encrypted")?[..]
+                            .to_vec(),
+                    ),
+                    flags,
+                })
+            }
+            // This arm catches all encrypted cases where super key is not present or cannot
+            // decrypt the blob, the latter being BlobValue::PwEncrypted.
+            _ => Err(Error::LockedComponent)
+                .context("In decrypt_if_required: Encountered encrypted blob without super key."),
+        }
+    }
+
     fn read_characteristics_file(
         &self,
         uid: u32,
         prefix: &str,
         alias: &str,
         hw_sec_level: SecurityLevel,
-    ) -> Result<Vec<KeyParameter>> {
+        super_key: &Option<Arc<dyn AesGcm>>,
+    ) -> Result<LegacyKeyCharacteristics> {
         let blob = Self::read_generic_blob(&self.make_chr_filename(uid, alias, prefix))
             .context("In read_characteristics_file")?;
 
         let blob = match blob {
-            None => return Ok(Vec::new()),
+            None => return Ok(LegacyKeyCharacteristics::Cache(Vec::new())),
             Some(blob) => blob,
         };
 
-        let mut stream = match blob.value() {
-            BlobValue::Characteristics(data) => &data[..],
-            BlobValue::CharacteristicsCache(data) => &data[..],
+        let blob = Self::decrypt_if_required(super_key, blob)
+            .context("In read_characteristics_file: Trying to decrypt blob.")?;
+
+        let (mut stream, is_cache) = match blob.value() {
+            BlobValue::Characteristics(data) => (&data[..], false),
+            BlobValue::CharacteristicsCache(data) => (&data[..], true),
             _ => {
                 return Err(KsError::Rc(ResponseCode::VALUE_CORRUPTED)).context(concat!(
                     "In read_characteristics_file: ",
@@ -589,7 +738,12 @@
             .into_iter()
             .map(|value| KeyParameter::new(value, SecurityLevel::KEYSTORE));
 
-        Ok(hw_list.into_iter().flatten().chain(sw_list).collect())
+        let params: Vec<KeyParameter> = hw_list.into_iter().flatten().chain(sw_list).collect();
+        if is_cache {
+            Ok(LegacyKeyCharacteristics::Cache(params))
+        } else {
+            Ok(LegacyKeyCharacteristics::File(params))
+        }
     }
 
     // This is a list of known prefixes that the Keystore 1.0 SPI used to use.
@@ -639,14 +793,40 @@
         Ok(Some(Self::new_from_stream(&mut file).context("In read_generic_blob.")?))
     }
 
+    fn read_generic_blob_decrypt_with<F>(path: &Path, decrypt: F) -> Result<Option<Blob>>
+    where
+        F: FnOnce(&[u8], &[u8], &[u8], Option<&[u8]>, Option<usize>) -> Result<ZVec>,
+    {
+        let mut file = match Self::with_retry_interrupted(|| File::open(path)) {
+            Ok(file) => file,
+            Err(e) => match e.kind() {
+                ErrorKind::NotFound => return Ok(None),
+                _ => return Err(e).context("In read_generic_blob_decrypt_with."),
+            },
+        };
+
+        Ok(Some(
+            Self::new_from_stream_decrypt_with(&mut file, decrypt)
+                .context("In read_generic_blob_decrypt_with.")?,
+        ))
+    }
+
     /// Read a legacy keystore entry blob.
-    pub fn read_legacy_keystore_entry(&self, uid: u32, alias: &str) -> Result<Option<Vec<u8>>> {
+    pub fn read_legacy_keystore_entry<F>(
+        &self,
+        uid: u32,
+        alias: &str,
+        decrypt: F,
+    ) -> Result<Option<Vec<u8>>>
+    where
+        F: FnOnce(&[u8], &[u8], &[u8], Option<&[u8]>, Option<usize>) -> Result<ZVec>,
+    {
         let path = match self.make_legacy_keystore_entry_filename(uid, alias) {
             Some(path) => path,
             None => return Ok(None),
         };
 
-        let blob = Self::read_generic_blob(&path)
+        let blob = Self::read_generic_blob_decrypt_with(&path, decrypt)
             .context("In read_legacy_keystore_entry: Failed to read blob.")?;
 
         Ok(blob.and_then(|blob| match blob.value {
@@ -659,22 +839,23 @@
     }
 
     /// Remove a legacy keystore entry by the name alias with owner uid.
-    pub fn remove_legacy_keystore_entry(&self, uid: u32, alias: &str) -> Result<()> {
+    pub fn remove_legacy_keystore_entry(&self, uid: u32, alias: &str) -> Result<bool> {
         let path = match self.make_legacy_keystore_entry_filename(uid, alias) {
             Some(path) => path,
-            None => return Ok(()),
+            None => return Ok(false),
         };
 
         if let Err(e) = Self::with_retry_interrupted(|| fs::remove_file(path.as_path())) {
             match e.kind() {
-                ErrorKind::NotFound => return Ok(()),
+                ErrorKind::NotFound => return Ok(false),
                 _ => return Err(e).context("In remove_legacy_keystore_entry."),
             }
         }
 
         let user_id = uid_to_android_user(uid);
         self.remove_user_dir_if_empty(user_id)
-            .context("In remove_legacy_keystore_entry: Trying to remove empty user dir.")
+            .context("In remove_legacy_keystore_entry: Trying to remove empty user dir.")?;
+        Ok(true)
     }
 
     /// List all entries belonging to the given uid.
@@ -988,6 +1169,88 @@
         Ok(something_was_deleted)
     }
 
+    /// This function moves a keystore file if it exists. It constructs the source and destination
+    /// file name using the make_filename function with the arguments uid, alias, and prefix.
+    /// The function overwrites existing destination files silently. If the source does not exist,
+    /// this function has no side effect and returns successfully.
+    fn move_keystore_file_if_exists<F>(
+        src_uid: u32,
+        dest_uid: u32,
+        src_alias: &str,
+        dest_alias: &str,
+        prefix: &str,
+        make_filename: F,
+    ) -> Result<()>
+    where
+        F: Fn(u32, &str, &str) -> PathBuf,
+    {
+        let src_path = make_filename(src_uid, src_alias, prefix);
+        let dest_path = make_filename(dest_uid, dest_alias, prefix);
+        match Self::with_retry_interrupted(|| fs::rename(&src_path, &dest_path)) {
+            Err(e) if e.kind() == ErrorKind::NotFound => Ok(()),
+            r => r.context("In move_keystore_file_if_exists: Trying to rename."),
+        }
+    }
+
+    /// Moves a keystore entry from one uid to another. The uids must have the same android user
+    /// component. Moves across android users are not permitted.
+    pub fn move_keystore_entry(
+        &self,
+        src_uid: u32,
+        dest_uid: u32,
+        src_alias: &str,
+        dest_alias: &str,
+    ) -> Result<()> {
+        if src_uid == dest_uid {
+            // Nothing to do in the trivial case.
+            return Ok(());
+        }
+
+        if uid_to_android_user(src_uid) != uid_to_android_user(dest_uid) {
+            return Err(Error::AndroidUserMismatch).context("In move_keystore_entry.");
+        }
+
+        let prefixes = ["USRPKEY", "USRSKEY", "USRCERT", "CACERT"];
+        for prefix in prefixes {
+            Self::move_keystore_file_if_exists(
+                src_uid,
+                dest_uid,
+                src_alias,
+                dest_alias,
+                prefix,
+                |uid, alias, prefix| self.make_blob_filename(uid, alias, prefix),
+            )
+            .with_context(|| {
+                format!(
+                    "In move_keystore_entry: Trying to move blob file with prefix: \"{}\"",
+                    prefix
+                )
+            })?;
+        }
+
+        let prefixes = ["USRPKEY", "USRSKEY"];
+
+        for prefix in prefixes {
+            Self::move_keystore_file_if_exists(
+                src_uid,
+                dest_uid,
+                src_alias,
+                dest_alias,
+                prefix,
+                |uid, alias, prefix| self.make_chr_filename(uid, alias, prefix),
+            )
+            .with_context(|| {
+                format!(
+                    "In move_keystore_entry: Trying to move characteristics file with \
+                     prefix: \"{}\"",
+                    prefix
+                )
+            })?;
+        }
+
+        Ok(())
+    }
+
     fn remove_user_dir_if_empty(&self, user_id: u32) -> Result<()> {
         if self
             .is_empty_user(user_id)
@@ -1004,79 +1267,66 @@
         &self,
         uid: u32,
         alias: &str,
-        key_manager: Option<&SuperKeyManager>,
-    ) -> Result<(Option<(Blob, Vec<KeyParameter>)>, Option<Vec<u8>>, Option<Vec<u8>>)> {
+        super_key: &Option<Arc<dyn AesGcm>>,
+    ) -> Result<(Option<(Blob, LegacyKeyCharacteristics)>, Option<Vec<u8>>, Option<Vec<u8>>)> {
         let km_blob = self.read_km_blob_file(uid, alias).context("In load_by_uid_alias.")?;
 
         let km_blob = match km_blob {
             Some((km_blob, prefix)) => {
-                let km_blob = match km_blob {
-                    Blob { flags: _, value: BlobValue::Decrypted(_) } => km_blob,
-                    // Unwrap the key blob if required and if we have key_manager.
-                    Blob { flags, value: BlobValue::Encrypted { ref iv, ref tag, ref data } } => {
-                        if let Some(key_manager) = key_manager {
-                            let decrypted = match key_manager
-                                .get_per_boot_key_by_user_id(uid_to_android_user(uid))
-                            {
-                                Some(key) => key.aes_gcm_decrypt(data, iv, tag).context(
-                                    "In load_by_uid_alias: while trying to decrypt legacy blob.",
-                                )?,
-                                None => {
-                                    return Err(KsError::Rc(ResponseCode::LOCKED)).context(format!(
-                                        concat!(
-                                            "In load_by_uid_alias: ",
-                                            "User {} has not unlocked the keystore yet.",
-                                        ),
-                                        uid_to_android_user(uid)
-                                    ))
-                                }
-                            };
-                            Blob { flags, value: BlobValue::Decrypted(decrypted) }
-                        } else {
-                            km_blob
-                        }
-                    }
-                    _ => {
-                        return Err(KsError::Rc(ResponseCode::VALUE_CORRUPTED)).context(
+                let km_blob =
+                    match km_blob {
+                        Blob { flags: _, value: BlobValue::Decrypted(_) }
+                        | Blob { flags: _, value: BlobValue::Encrypted { .. } } => km_blob,
+                        _ => return Err(KsError::Rc(ResponseCode::VALUE_CORRUPTED)).context(
                             "In load_by_uid_alias: Found wrong blob type in legacy key blob file.",
-                        )
-                    }
-                };
+                        ),
+                    };
 
                 let hw_sec_level = match km_blob.is_strongbox() {
                     true => SecurityLevel::STRONGBOX,
                     false => SecurityLevel::TRUSTED_ENVIRONMENT,
                 };
                 let key_parameters = self
-                    .read_characteristics_file(uid, &prefix, alias, hw_sec_level)
+                    .read_characteristics_file(uid, &prefix, alias, hw_sec_level, super_key)
                     .context("In load_by_uid_alias.")?;
                 Some((km_blob, key_parameters))
             }
             None => None,
         };
 
-        let user_cert =
-            match Self::read_generic_blob(&self.make_blob_filename(uid, alias, "USRCERT"))
-                .context("In load_by_uid_alias: While loading user cert.")?
-            {
-                Some(Blob { value: BlobValue::Generic(data), .. }) => Some(data),
-                None => None,
-                _ => {
-                    return Err(KsError::Rc(ResponseCode::VALUE_CORRUPTED)).context(
-                        "In load_by_uid_alias: Found unexpected blob type in USRCERT file",
-                    )
-                }
-            };
+        let user_cert_blob =
+            Self::read_generic_blob(&self.make_blob_filename(uid, alias, "USRCERT"))
+                .context("In load_by_uid_alias: While loading user cert.")?;
 
-        let ca_cert = match Self::read_generic_blob(&self.make_blob_filename(uid, alias, "CACERT"))
-            .context("In load_by_uid_alias: While loading ca cert.")?
-        {
-            Some(Blob { value: BlobValue::Generic(data), .. }) => Some(data),
-            None => None,
-            _ => {
+        let user_cert = if let Some(blob) = user_cert_blob {
+            let blob = Self::decrypt_if_required(super_key, blob)
+                .context("In load_by_uid_alias: While decrypting user cert.")?;
+
+            if let Blob { value: BlobValue::Generic(data), .. } = blob {
+                Some(data)
+            } else {
                 return Err(KsError::Rc(ResponseCode::VALUE_CORRUPTED))
-                    .context("In load_by_uid_alias: Found unexpected blob type in CACERT file")
+                    .context("In load_by_uid_alias: Found unexpected blob type in USRCERT file");
             }
+        } else {
+            None
+        };
+
+        let ca_cert_blob = Self::read_generic_blob(&self.make_blob_filename(uid, alias, "CACERT"))
+            .context("In load_by_uid_alias: While loading ca cert.")?;
+
+        let ca_cert = if let Some(blob) = ca_cert_blob {
+            let blob = Self::decrypt_if_required(super_key, blob)
+                .context("In load_by_uid_alias: While decrypting ca cert.")?;
+
+            if let Blob { value: BlobValue::Generic(data), .. } = blob {
+                Some(data)
+            } else {
+                return Err(KsError::Rc(ResponseCode::VALUE_CORRUPTED))
+                    .context("In load_by_uid_alias: Found unexpected blob type in CACERT file");
+            }
+        } else {
+            None
         };
 
         Ok((km_blob, user_cert, ca_cert))
@@ -1139,15 +1389,271 @@
 
 #[cfg(test)]
 mod test {
+    #![allow(dead_code)]
     use super::*;
-    use anyhow::anyhow;
-    use keystore2_crypto::aes_gcm_decrypt;
+    use keystore2_crypto::{aes_gcm_decrypt, aes_gcm_encrypt};
     use rand::Rng;
     use std::string::FromUtf8Error;
     mod legacy_blob_test_vectors;
-    use crate::error;
+    use crate::legacy_blob::blob_types::{
+        GENERIC, KEY_CHARACTERISTICS, KEY_CHARACTERISTICS_CACHE, KM_BLOB, SUPER_KEY,
+        SUPER_KEY_AES256,
+    };
     use crate::legacy_blob::test::legacy_blob_test_vectors::*;
+    use anyhow::{anyhow, Result};
     use keystore2_test_utils::TempDir;
+    use std::convert::TryInto;
+    use std::fs::OpenOptions;
+    use std::io::Write;
+    use std::ops::Deref;
+
+    /// This function takes a blob and synchronizes the encrypted/super encrypted flags
+    /// with the blob type for the pairs Generic/EncryptedGeneric,
+    /// Characteristics/EncryptedCharacteristics and Encrypted/Decrypted.
+    /// E.g. if a non encrypted enum variant is encountered with flags::SUPER_ENCRYPTED
+    /// or flags::ENCRYPTED is set, the payload is encrypted and the corresponding
+    /// encrypted variant is returned, and vice versa. All other variants remain untouched
+    /// even if flags and BlobValue variant are inconsistent.
+    fn prepare_blob(blob: Blob, key: &[u8]) -> Result<Blob> {
+        match blob {
+            Blob { value: BlobValue::Generic(data), flags } if blob.is_encrypted() => {
+                let (ciphertext, iv, tag) = aes_gcm_encrypt(&data, key).unwrap();
+                Ok(Blob { value: BlobValue::EncryptedGeneric { data: ciphertext, iv, tag }, flags })
+            }
+            Blob { value: BlobValue::Characteristics(data), flags } if blob.is_encrypted() => {
+                let (ciphertext, iv, tag) = aes_gcm_encrypt(&data, key).unwrap();
+                Ok(Blob {
+                    value: BlobValue::EncryptedCharacteristics { data: ciphertext, iv, tag },
+                    flags,
+                })
+            }
+            Blob { value: BlobValue::Decrypted(data), flags } if blob.is_encrypted() => {
+                let (ciphertext, iv, tag) = aes_gcm_encrypt(&data, key).unwrap();
+                Ok(Blob { value: BlobValue::Encrypted { data: ciphertext, iv, tag }, flags })
+            }
+            Blob { value: BlobValue::EncryptedGeneric { data, iv, tag }, flags }
+                if !blob.is_encrypted() =>
+            {
+                let plaintext = aes_gcm_decrypt(&data, &iv, &tag, key).unwrap();
+                Ok(Blob { value: BlobValue::Generic(plaintext[..].to_vec()), flags })
+            }
+            Blob { value: BlobValue::EncryptedCharacteristics { data, iv, tag }, flags }
+                if !blob.is_encrypted() =>
+            {
+                let plaintext = aes_gcm_decrypt(&data, &iv, &tag, key).unwrap();
+                Ok(Blob { value: BlobValue::Characteristics(plaintext[..].to_vec()), flags })
+            }
+            Blob { value: BlobValue::Encrypted { data, iv, tag }, flags }
+                if !blob.is_encrypted() =>
+            {
+                let plaintext = aes_gcm_decrypt(&data, &iv, &tag, key).unwrap();
+                Ok(Blob { value: BlobValue::Decrypted(plaintext), flags })
+            }
+            _ => Ok(blob),
+        }
+    }
+
+    struct LegacyBlobHeader {
+        version: u8,
+        blob_type: u8,
+        flags: u8,
+        info: u8,
+        iv: [u8; 12],
+        tag: [u8; 16],
+        blob_size: u32,
+    }
+
+    /// This function takes a Blob and writes it to out as a legacy blob file
+    /// version 3. Note that the flags field and the values field may be
+    /// inconsistent and could be sanitized by this function. It is intentionally
+    /// not done to enable tests to construct malformed blobs.
+    fn write_legacy_blob(out: &mut dyn Write, blob: Blob) -> Result<usize> {
+        let (header, data, salt) = match blob {
+            Blob { value: BlobValue::Generic(data), flags } => (
+                LegacyBlobHeader {
+                    version: 3,
+                    blob_type: GENERIC,
+                    flags,
+                    info: 0,
+                    iv: [0u8; 12],
+                    tag: [0u8; 16],
+                    blob_size: data.len() as u32,
+                },
+                data,
+                None,
+            ),
+            Blob { value: BlobValue::Characteristics(data), flags } => (
+                LegacyBlobHeader {
+                    version: 3,
+                    blob_type: KEY_CHARACTERISTICS,
+                    flags,
+                    info: 0,
+                    iv: [0u8; 12],
+                    tag: [0u8; 16],
+                    blob_size: data.len() as u32,
+                },
+                data,
+                None,
+            ),
+            Blob { value: BlobValue::CharacteristicsCache(data), flags } => (
+                LegacyBlobHeader {
+                    version: 3,
+                    blob_type: KEY_CHARACTERISTICS_CACHE,
+                    flags,
+                    info: 0,
+                    iv: [0u8; 12],
+                    tag: [0u8; 16],
+                    blob_size: data.len() as u32,
+                },
+                data,
+                None,
+            ),
+            Blob { value: BlobValue::PwEncrypted { iv, tag, data, salt, key_size }, flags } => (
+                LegacyBlobHeader {
+                    version: 3,
+                    blob_type: if key_size == keystore2_crypto::AES_128_KEY_LENGTH {
+                        SUPER_KEY
+                    } else {
+                        SUPER_KEY_AES256
+                    },
+                    flags,
+                    info: 0,
+                    iv: iv.try_into().unwrap(),
+                    tag: tag[..].try_into().unwrap(),
+                    blob_size: data.len() as u32,
+                },
+                data,
+                Some(salt),
+            ),
+            Blob { value: BlobValue::Encrypted { iv, tag, data }, flags } => (
+                LegacyBlobHeader {
+                    version: 3,
+                    blob_type: KM_BLOB,
+                    flags,
+                    info: 0,
+                    iv: iv.try_into().unwrap(),
+                    tag: tag[..].try_into().unwrap(),
+                    blob_size: data.len() as u32,
+                },
+                data,
+                None,
+            ),
+            Blob { value: BlobValue::EncryptedGeneric { iv, tag, data }, flags } => (
+                LegacyBlobHeader {
+                    version: 3,
+                    blob_type: GENERIC,
+                    flags,
+                    info: 0,
+                    iv: iv.try_into().unwrap(),
+                    tag: tag[..].try_into().unwrap(),
+                    blob_size: data.len() as u32,
+                },
+                data,
+                None,
+            ),
+            Blob { value: BlobValue::EncryptedCharacteristics { iv, tag, data }, flags } => (
+                LegacyBlobHeader {
+                    version: 3,
+                    blob_type: KEY_CHARACTERISTICS,
+                    flags,
+                    info: 0,
+                    iv: iv.try_into().unwrap(),
+                    tag: tag[..].try_into().unwrap(),
+                    blob_size: data.len() as u32,
+                },
+                data,
+                None,
+            ),
+            Blob { value: BlobValue::Decrypted(data), flags } => (
+                LegacyBlobHeader {
+                    version: 3,
+                    blob_type: KM_BLOB,
+                    flags,
+                    info: 0,
+                    iv: [0u8; 12],
+                    tag: [0u8; 16],
+                    blob_size: data.len() as u32,
+                },
+                data[..].to_vec(),
+                None,
+            ),
+        };
+        write_legacy_blob_helper(out, &header, &data, salt.as_deref())
+    }
+
+    fn write_legacy_blob_helper(
+        out: &mut dyn Write,
+        header: &LegacyBlobHeader,
+        data: &[u8],
+        info: Option<&[u8]>,
+    ) -> Result<usize> {
+        if 1 != out.write(&[header.version])? {
+            return Err(anyhow!("Unexpected size while writing version."));
+        }
+        if 1 != out.write(&[header.blob_type])? {
+            return Err(anyhow!("Unexpected size while writing blob_type."));
+        }
+        if 1 != out.write(&[header.flags])? {
+            return Err(anyhow!("Unexpected size while writing flags."));
+        }
+        if 1 != out.write(&[header.info])? {
+            return Err(anyhow!("Unexpected size while writing info."));
+        }
+        if 12 != out.write(&header.iv)? {
+            return Err(anyhow!("Unexpected size while writing iv."));
+        }
+        if 4 != out.write(&[0u8; 4])? {
+            return Err(anyhow!("Unexpected size while writing last 4 bytes of iv."));
+        }
+        if 16 != out.write(&header.tag)? {
+            return Err(anyhow!("Unexpected size while writing tag."));
+        }
+        if 4 != out.write(&header.blob_size.to_be_bytes())? {
+            return Err(anyhow!("Unexpected size while writing blob size."));
+        }
+        if data.len() != out.write(data)? {
+            return Err(anyhow!("Unexpected size while writing blob."));
+        }
+        if let Some(info) = info {
+            if info.len() != out.write(info)? {
+                return Err(anyhow!("Unexpected size while writing inof."));
+            }
+        }
+        Ok(40 + data.len() + info.map(|v| v.len()).unwrap_or(0))
+    }
+
+    fn make_encrypted_characteristics_file<P: AsRef<Path>>(path: P, key: &[u8]) -> Result<()> {
+        let mut file = OpenOptions::new().write(true).create_new(true).open(path).unwrap();
+        let blob = Blob {
+            value: BlobValue::Characteristics(KEY_PARAMETERS.to_vec()),
+            flags: flags::ENCRYPTED,
+        };
+        let blob = prepare_blob(blob, key).unwrap();
+        write_legacy_blob(&mut file, blob).unwrap();
+        Ok(())
+    }
+
+    fn make_encrypted_usr_cert_file<P: AsRef<Path>>(path: P, key: &[u8]) -> Result<()> {
+        let mut file = OpenOptions::new().write(true).create_new(true).open(path).unwrap();
+        let blob = Blob {
+            value: BlobValue::Generic(LOADED_CERT_AUTHBOUND.to_vec()),
+            flags: flags::ENCRYPTED,
+        };
+        let blob = prepare_blob(blob, key).unwrap();
+        write_legacy_blob(&mut file, blob).unwrap();
+        Ok(())
+    }
+
+    fn make_encrypted_ca_cert_file<P: AsRef<Path>>(path: P, key: &[u8]) -> Result<()> {
+        let mut file = OpenOptions::new().write(true).create_new(true).open(path).unwrap();
+        let blob = Blob {
+            value: BlobValue::Generic(LOADED_CACERT_AUTHBOUND.to_vec()),
+            flags: flags::ENCRYPTED,
+        };
+        let blob = prepare_blob(blob, key).unwrap();
+        write_legacy_blob(&mut file, blob).unwrap();
+        Ok(())
+    }
 
     #[test]
     fn decode_encode_alias_test() {
@@ -1203,7 +1709,8 @@
     fn read_golden_key_blob_test() -> anyhow::Result<()> {
         let blob = LegacyBlobLoader::new_from_stream_decrypt_with(&mut &*BLOB, |_, _, _, _, _| {
             Err(anyhow!("should not be called"))
-        })?;
+        })
+        .unwrap();
         assert!(!blob.is_encrypted());
         assert!(!blob.is_fallback());
         assert!(!blob.is_strongbox());
@@ -1213,7 +1720,8 @@
         let blob = LegacyBlobLoader::new_from_stream_decrypt_with(
             &mut &*REAL_LEGACY_BLOB,
             |_, _, _, _, _| Err(anyhow!("should not be called")),
-        )?;
+        )
+        .unwrap();
         assert!(!blob.is_encrypted());
         assert!(!blob.is_fallback());
         assert!(!blob.is_strongbox());
@@ -1301,62 +1809,75 @@
 
     #[test]
     fn test_legacy_blobs() -> anyhow::Result<()> {
-        let temp_dir = TempDir::new("legacy_blob_test")?;
-        std::fs::create_dir(&*temp_dir.build().push("user_0"))?;
+        let temp_dir = TempDir::new("legacy_blob_test").unwrap();
+        std::fs::create_dir(&*temp_dir.build().push("user_0")).unwrap();
 
-        std::fs::write(&*temp_dir.build().push("user_0").push(".masterkey"), SUPERKEY)?;
+        std::fs::write(&*temp_dir.build().push("user_0").push(".masterkey"), SUPERKEY).unwrap();
 
         std::fs::write(
             &*temp_dir.build().push("user_0").push("10223_USRPKEY_authbound"),
             USRPKEY_AUTHBOUND,
-        )?;
+        )
+        .unwrap();
         std::fs::write(
             &*temp_dir.build().push("user_0").push(".10223_chr_USRPKEY_authbound"),
             USRPKEY_AUTHBOUND_CHR,
-        )?;
+        )
+        .unwrap();
         std::fs::write(
             &*temp_dir.build().push("user_0").push("10223_USRCERT_authbound"),
             USRCERT_AUTHBOUND,
-        )?;
+        )
+        .unwrap();
         std::fs::write(
             &*temp_dir.build().push("user_0").push("10223_CACERT_authbound"),
             CACERT_AUTHBOUND,
-        )?;
+        )
+        .unwrap();
 
         std::fs::write(
             &*temp_dir.build().push("user_0").push("10223_USRPKEY_non_authbound"),
             USRPKEY_NON_AUTHBOUND,
-        )?;
+        )
+        .unwrap();
         std::fs::write(
             &*temp_dir.build().push("user_0").push(".10223_chr_USRPKEY_non_authbound"),
             USRPKEY_NON_AUTHBOUND_CHR,
-        )?;
+        )
+        .unwrap();
         std::fs::write(
             &*temp_dir.build().push("user_0").push("10223_USRCERT_non_authbound"),
             USRCERT_NON_AUTHBOUND,
-        )?;
+        )
+        .unwrap();
         std::fs::write(
             &*temp_dir.build().push("user_0").push("10223_CACERT_non_authbound"),
             CACERT_NON_AUTHBOUND,
-        )?;
+        )
+        .unwrap();
 
-        let mut key_manager: SuperKeyManager = Default::default();
-        let mut db = crate::database::KeystoreDB::new(temp_dir.path(), None)?;
         let legacy_blob_loader = LegacyBlobLoader::new(temp_dir.path());
 
-        assert_eq!(
-            legacy_blob_loader
-                .load_by_uid_alias(10223, "authbound", Some(&key_manager))
-                .unwrap_err()
-                .root_cause()
-                .downcast_ref::<error::Error>(),
-            Some(&error::Error::Rc(ResponseCode::LOCKED))
-        );
-
-        key_manager.unlock_user_key(&mut db, 0, &(PASSWORD.into()), &legacy_blob_loader)?;
+        if let (Some((Blob { flags, value }, _params)), Some(cert), Some(chain)) =
+            legacy_blob_loader.load_by_uid_alias(10223, "authbound", &None)?
+        {
+            assert_eq!(flags, 4);
+            assert_eq!(
+                value,
+                BlobValue::Encrypted {
+                    data: USRPKEY_AUTHBOUND_ENC_PAYLOAD.to_vec(),
+                    iv: USRPKEY_AUTHBOUND_IV.to_vec(),
+                    tag: USRPKEY_AUTHBOUND_TAG.to_vec()
+                }
+            );
+            assert_eq!(&cert[..], LOADED_CERT_AUTHBOUND);
+            assert_eq!(&chain[..], LOADED_CACERT_AUTHBOUND);
+        } else {
+            panic!("");
+        }
 
         if let (Some((Blob { flags, value: _ }, _params)), Some(cert), Some(chain)) =
-            legacy_blob_loader.load_by_uid_alias(10223, "authbound", Some(&key_manager))?
+            legacy_blob_loader.load_by_uid_alias(10223, "authbound", &None)?
         {
             assert_eq!(flags, 4);
             //assert_eq!(value, BlobValue::Encrypted(..));
@@ -1366,7 +1887,7 @@
             panic!("");
         }
         if let (Some((Blob { flags, value }, _params)), Some(cert), Some(chain)) =
-            legacy_blob_loader.load_by_uid_alias(10223, "non_authbound", Some(&key_manager))?
+            legacy_blob_loader.load_by_uid_alias(10223, "non_authbound", &None)?
         {
             assert_eq!(flags, 0);
             assert_eq!(value, BlobValue::Decrypted(LOADED_USRPKEY_NON_AUTHBOUND.try_into()?));
@@ -1383,11 +1904,11 @@
 
         assert_eq!(
             (None, None, None),
-            legacy_blob_loader.load_by_uid_alias(10223, "authbound", Some(&key_manager))?
+            legacy_blob_loader.load_by_uid_alias(10223, "authbound", &None)?
         );
         assert_eq!(
             (None, None, None),
-            legacy_blob_loader.load_by_uid_alias(10223, "non_authbound", Some(&key_manager))?
+            legacy_blob_loader.load_by_uid_alias(10223, "non_authbound", &None)?
         );
 
         // The database should not be empty due to the super key.
@@ -1406,9 +1927,314 @@
         Ok(())
     }
 
+    struct TestKey(ZVec);
+
+    impl crate::utils::AesGcmKey for TestKey {
+        fn key(&self) -> &[u8] {
+            &self.0
+        }
+    }
+
+    impl Deref for TestKey {
+        type Target = [u8];
+        fn deref(&self) -> &Self::Target {
+            &self.0
+        }
+    }
+
+    #[test]
+    fn test_with_encrypted_characteristics() -> anyhow::Result<()> {
+        let temp_dir = TempDir::new("test_with_encrypted_characteristics").unwrap();
+        std::fs::create_dir(&*temp_dir.build().push("user_0")).unwrap();
+
+        let pw: Password = PASSWORD.into();
+        let pw_key = TestKey(pw.derive_key(Some(SUPERKEY_SALT), 32).unwrap());
+        let super_key =
+            Arc::new(TestKey(pw_key.decrypt(SUPERKEY_PAYLOAD, SUPERKEY_IV, SUPERKEY_TAG).unwrap()));
+
+        std::fs::write(&*temp_dir.build().push("user_0").push(".masterkey"), SUPERKEY).unwrap();
+
+        std::fs::write(
+            &*temp_dir.build().push("user_0").push("10223_USRPKEY_authbound"),
+            USRPKEY_AUTHBOUND,
+        )
+        .unwrap();
+        make_encrypted_characteristics_file(
+            &*temp_dir.build().push("user_0").push(".10223_chr_USRPKEY_authbound"),
+            &super_key,
+        )
+        .unwrap();
+        std::fs::write(
+            &*temp_dir.build().push("user_0").push("10223_USRCERT_authbound"),
+            USRCERT_AUTHBOUND,
+        )
+        .unwrap();
+        std::fs::write(
+            &*temp_dir.build().push("user_0").push("10223_CACERT_authbound"),
+            CACERT_AUTHBOUND,
+        )
+        .unwrap();
+
+        let legacy_blob_loader = LegacyBlobLoader::new(temp_dir.path());
+
+        assert_eq!(
+            legacy_blob_loader
+                .load_by_uid_alias(10223, "authbound", &None)
+                .unwrap_err()
+                .root_cause()
+                .downcast_ref::<Error>(),
+            Some(&Error::LockedComponent)
+        );
+
+        assert_eq!(
+            legacy_blob_loader.load_by_uid_alias(10223, "authbound", &Some(super_key)).unwrap(),
+            (
+                Some((
+                    Blob {
+                        flags: 4,
+                        value: BlobValue::Encrypted {
+                            data: USRPKEY_AUTHBOUND_ENC_PAYLOAD.to_vec(),
+                            iv: USRPKEY_AUTHBOUND_IV.to_vec(),
+                            tag: USRPKEY_AUTHBOUND_TAG.to_vec()
+                        }
+                    },
+                    structured_test_params()
+                )),
+                Some(LOADED_CERT_AUTHBOUND.to_vec()),
+                Some(LOADED_CACERT_AUTHBOUND.to_vec())
+            )
+        );
+
+        legacy_blob_loader.remove_keystore_entry(10223, "authbound").expect("This should succeed.");
+
+        assert_eq!(
+            (None, None, None),
+            legacy_blob_loader.load_by_uid_alias(10223, "authbound", &None).unwrap()
+        );
+
+        // The database should not be empty due to the super key.
+        assert!(!legacy_blob_loader.is_empty().unwrap());
+        assert!(!legacy_blob_loader.is_empty_user(0).unwrap());
+
+        // The database should be considered empty for user 1.
+        assert!(legacy_blob_loader.is_empty_user(1).unwrap());
+
+        legacy_blob_loader.remove_super_key(0);
+
+        // Now it should be empty.
+        assert!(legacy_blob_loader.is_empty_user(0).unwrap());
+        assert!(legacy_blob_loader.is_empty().unwrap());
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_with_encrypted_certificates() -> anyhow::Result<()> {
+        let temp_dir = TempDir::new("test_with_encrypted_certificates").unwrap();
+        std::fs::create_dir(&*temp_dir.build().push("user_0")).unwrap();
+
+        let pw: Password = PASSWORD.into();
+        let pw_key = TestKey(pw.derive_key(Some(SUPERKEY_SALT), 32).unwrap());
+        let super_key =
+            Arc::new(TestKey(pw_key.decrypt(SUPERKEY_PAYLOAD, SUPERKEY_IV, SUPERKEY_TAG).unwrap()));
+
+        std::fs::write(&*temp_dir.build().push("user_0").push(".masterkey"), SUPERKEY).unwrap();
+
+        std::fs::write(
+            &*temp_dir.build().push("user_0").push("10223_USRPKEY_authbound"),
+            USRPKEY_AUTHBOUND,
+        )
+        .unwrap();
+        std::fs::write(
+            &*temp_dir.build().push("user_0").push(".10223_chr_USRPKEY_authbound"),
+            USRPKEY_AUTHBOUND_CHR,
+        )
+        .unwrap();
+        make_encrypted_usr_cert_file(
+            &*temp_dir.build().push("user_0").push("10223_USRCERT_authbound"),
+            &super_key,
+        )
+        .unwrap();
+        make_encrypted_ca_cert_file(
+            &*temp_dir.build().push("user_0").push("10223_CACERT_authbound"),
+            &super_key,
+        )
+        .unwrap();
+
+        let legacy_blob_loader = LegacyBlobLoader::new(temp_dir.path());
+
+        assert_eq!(
+            legacy_blob_loader
+                .load_by_uid_alias(10223, "authbound", &None)
+                .unwrap_err()
+                .root_cause()
+                .downcast_ref::<Error>(),
+            Some(&Error::LockedComponent)
+        );
+
+        assert_eq!(
+            legacy_blob_loader.load_by_uid_alias(10223, "authbound", &Some(super_key)).unwrap(),
+            (
+                Some((
+                    Blob {
+                        flags: 4,
+                        value: BlobValue::Encrypted {
+                            data: USRPKEY_AUTHBOUND_ENC_PAYLOAD.to_vec(),
+                            iv: USRPKEY_AUTHBOUND_IV.to_vec(),
+                            tag: USRPKEY_AUTHBOUND_TAG.to_vec()
+                        }
+                    },
+                    structured_test_params_cache()
+                )),
+                Some(LOADED_CERT_AUTHBOUND.to_vec()),
+                Some(LOADED_CACERT_AUTHBOUND.to_vec())
+            )
+        );
+
+        legacy_blob_loader.remove_keystore_entry(10223, "authbound").expect("This should succeed.");
+
+        assert_eq!(
+            (None, None, None),
+            legacy_blob_loader.load_by_uid_alias(10223, "authbound", &None).unwrap()
+        );
+
+        // The database should not be empty due to the super key.
+        assert!(!legacy_blob_loader.is_empty().unwrap());
+        assert!(!legacy_blob_loader.is_empty_user(0).unwrap());
+
+        // The database should be considered empty for user 1.
+        assert!(legacy_blob_loader.is_empty_user(1).unwrap());
+
+        legacy_blob_loader.remove_super_key(0);
+
+        // Now it should be empty.
+        assert!(legacy_blob_loader.is_empty_user(0).unwrap());
+        assert!(legacy_blob_loader.is_empty().unwrap());
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_in_place_key_migration() -> anyhow::Result<()> {
+        let temp_dir = TempDir::new("test_in_place_key_migration").unwrap();
+        std::fs::create_dir(&*temp_dir.build().push("user_0")).unwrap();
+
+        let pw: Password = PASSWORD.into();
+        let pw_key = TestKey(pw.derive_key(Some(SUPERKEY_SALT), 32).unwrap());
+        let super_key =
+            Arc::new(TestKey(pw_key.decrypt(SUPERKEY_PAYLOAD, SUPERKEY_IV, SUPERKEY_TAG).unwrap()));
+
+        std::fs::write(&*temp_dir.build().push("user_0").push(".masterkey"), SUPERKEY).unwrap();
+
+        std::fs::write(
+            &*temp_dir.build().push("user_0").push("10223_USRPKEY_authbound"),
+            USRPKEY_AUTHBOUND,
+        )
+        .unwrap();
+        std::fs::write(
+            &*temp_dir.build().push("user_0").push(".10223_chr_USRPKEY_authbound"),
+            USRPKEY_AUTHBOUND_CHR,
+        )
+        .unwrap();
+        make_encrypted_usr_cert_file(
+            &*temp_dir.build().push("user_0").push("10223_USRCERT_authbound"),
+            &super_key,
+        )
+        .unwrap();
+        make_encrypted_ca_cert_file(
+            &*temp_dir.build().push("user_0").push("10223_CACERT_authbound"),
+            &super_key,
+        )
+        .unwrap();
+
+        let legacy_blob_loader = LegacyBlobLoader::new(temp_dir.path());
+
+        assert_eq!(
+            legacy_blob_loader
+                .load_by_uid_alias(10223, "authbound", &None)
+                .unwrap_err()
+                .root_cause()
+                .downcast_ref::<Error>(),
+            Some(&Error::LockedComponent)
+        );
+
+        let super_key: Option<Arc<dyn AesGcm>> = Some(super_key);
+
+        assert_eq!(
+            legacy_blob_loader.load_by_uid_alias(10223, "authbound", &super_key).unwrap(),
+            (
+                Some((
+                    Blob {
+                        flags: 4,
+                        value: BlobValue::Encrypted {
+                            data: USRPKEY_AUTHBOUND_ENC_PAYLOAD.to_vec(),
+                            iv: USRPKEY_AUTHBOUND_IV.to_vec(),
+                            tag: USRPKEY_AUTHBOUND_TAG.to_vec()
+                        }
+                    },
+                    structured_test_params_cache()
+                )),
+                Some(LOADED_CERT_AUTHBOUND.to_vec()),
+                Some(LOADED_CACERT_AUTHBOUND.to_vec())
+            )
+        );
+
+        legacy_blob_loader.move_keystore_entry(10223, 10224, "authbound", "boundauth").unwrap();
+
+        assert_eq!(
+            legacy_blob_loader
+                .load_by_uid_alias(10224, "boundauth", &None)
+                .unwrap_err()
+                .root_cause()
+                .downcast_ref::<Error>(),
+            Some(&Error::LockedComponent)
+        );
+
+        assert_eq!(
+            legacy_blob_loader.load_by_uid_alias(10224, "boundauth", &super_key).unwrap(),
+            (
+                Some((
+                    Blob {
+                        flags: 4,
+                        value: BlobValue::Encrypted {
+                            data: USRPKEY_AUTHBOUND_ENC_PAYLOAD.to_vec(),
+                            iv: USRPKEY_AUTHBOUND_IV.to_vec(),
+                            tag: USRPKEY_AUTHBOUND_TAG.to_vec()
+                        }
+                    },
+                    structured_test_params_cache()
+                )),
+                Some(LOADED_CERT_AUTHBOUND.to_vec()),
+                Some(LOADED_CACERT_AUTHBOUND.to_vec())
+            )
+        );
+
+        legacy_blob_loader.remove_keystore_entry(10224, "boundauth").expect("This should succeed.");
+
+        assert_eq!(
+            (None, None, None),
+            legacy_blob_loader.load_by_uid_alias(10224, "boundauth", &None).unwrap()
+        );
+
+        // The database should not be empty due to the super key.
+        assert!(!legacy_blob_loader.is_empty().unwrap());
+        assert!(!legacy_blob_loader.is_empty_user(0).unwrap());
+
+        // The database should be considered empty for user 1.
+        assert!(legacy_blob_loader.is_empty_user(1).unwrap());
+
+        legacy_blob_loader.remove_super_key(0);
+
+        // Now it should be empty.
+        assert!(legacy_blob_loader.is_empty_user(0).unwrap());
+        assert!(legacy_blob_loader.is_empty().unwrap());
+
+        Ok(())
+    }
+
     #[test]
     fn list_non_existing_user() -> Result<()> {
-        let temp_dir = TempDir::new("list_non_existing_user")?;
+        let temp_dir = TempDir::new("list_non_existing_user").unwrap();
         let legacy_blob_loader = LegacyBlobLoader::new(temp_dir.path());
 
         assert!(legacy_blob_loader.list_user(20)?.is_empty());
@@ -1418,11 +2244,66 @@
 
     #[test]
     fn list_legacy_keystore_entries_on_non_existing_user() -> Result<()> {
-        let temp_dir = TempDir::new("list_legacy_keystore_entries_on_non_existing_user")?;
+        let temp_dir = TempDir::new("list_legacy_keystore_entries_on_non_existing_user").unwrap();
         let legacy_blob_loader = LegacyBlobLoader::new(temp_dir.path());
 
         assert!(legacy_blob_loader.list_legacy_keystore_entries_for_user(20)?.is_empty());
 
         Ok(())
     }
+
+    #[test]
+    fn test_move_keystore_entry() {
+        let temp_dir = TempDir::new("test_move_keystore_entry").unwrap();
+        std::fs::create_dir(&*temp_dir.build().push("user_0")).unwrap();
+
+        const SOME_CONTENT: &[u8] = b"some content";
+        const ANOTHER_CONTENT: &[u8] = b"another content";
+        const SOME_FILENAME: &str = "some_file";
+        const ANOTHER_FILENAME: &str = "another_file";
+
+        std::fs::write(&*temp_dir.build().push("user_0").push(SOME_FILENAME), SOME_CONTENT)
+            .unwrap();
+
+        std::fs::write(&*temp_dir.build().push("user_0").push(ANOTHER_FILENAME), ANOTHER_CONTENT)
+            .unwrap();
+
+        // Non existent source id silently ignored.
+        assert!(LegacyBlobLoader::move_keystore_file_if_exists(
+            1,
+            2,
+            "non_existent",
+            ANOTHER_FILENAME,
+            "ignored",
+            |_, alias, _| temp_dir.build().push("user_0").push(alias).to_path_buf()
+        )
+        .is_ok());
+
+        // Content of another_file has not changed.
+        let another_content =
+            std::fs::read(&*temp_dir.build().push("user_0").push(ANOTHER_FILENAME)).unwrap();
+        assert_eq!(&another_content, ANOTHER_CONTENT);
+
+        // Check that some_file still exists.
+        assert!(temp_dir.build().push("user_0").push(SOME_FILENAME).exists());
+        // Existing target files are silently overwritten.
+
+        assert!(LegacyBlobLoader::move_keystore_file_if_exists(
+            1,
+            2,
+            SOME_FILENAME,
+            ANOTHER_FILENAME,
+            "ignored",
+            |_, alias, _| temp_dir.build().push("user_0").push(alias).to_path_buf()
+        )
+        .is_ok());
+
+        // Content of another_file is now "some content".
+        let another_content =
+            std::fs::read(&*temp_dir.build().push("user_0").push(ANOTHER_FILENAME)).unwrap();
+        assert_eq!(&another_content, SOME_CONTENT);
+
+        // Check that some_file no longer exists.
+        assert!(!temp_dir.build().push("user_0").push(SOME_FILENAME).exists());
+    }
 }
diff --git a/keystore2/src/legacy_blob/test/legacy_blob_test_vectors.rs b/keystore2/src/legacy_blob/test/legacy_blob_test_vectors.rs
index 14bd40c..2049ac2 100644
--- a/keystore2/src/legacy_blob/test/legacy_blob_test_vectors.rs
+++ b/keystore2/src/legacy_blob/test/legacy_blob_test_vectors.rs
@@ -12,6 +12,14 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use crate::key_parameter::{KeyParameter, KeyParameterValue};
+use crate::legacy_blob::LegacyKeyCharacteristics;
+use android_hardware_security_keymint::aidl::android::hardware::security::keymint::{
+    Algorithm::Algorithm, Digest::Digest, EcCurve::EcCurve,
+    HardwareAuthenticatorType::HardwareAuthenticatorType, KeyOrigin::KeyOrigin,
+    KeyPurpose::KeyPurpose, SecurityLevel::SecurityLevel,
+};
+
 pub static BLOB: &[u8] = &[
     3, // version
     1, // type
@@ -22,6 +30,106 @@
     0, 0, 0, 4, // length in big endian
     0xde, 0xed, 0xbe, 0xef, // payload
 ];
+
+pub fn structured_test_params() -> LegacyKeyCharacteristics {
+    LegacyKeyCharacteristics::File(vec![
+        KeyParameter::new(KeyParameterValue::KeyPurpose(KeyPurpose::SIGN), SecurityLevel::KEYSTORE),
+        KeyParameter::new(
+            KeyParameterValue::KeyPurpose(KeyPurpose::VERIFY),
+            SecurityLevel::KEYSTORE,
+        ),
+        KeyParameter::new(KeyParameterValue::Digest(Digest::SHA_2_256), SecurityLevel::KEYSTORE),
+        KeyParameter::new(
+            KeyParameterValue::UserSecureID(2100322049669824240),
+            SecurityLevel::KEYSTORE,
+        ),
+        KeyParameter::new(KeyParameterValue::Algorithm(Algorithm::EC), SecurityLevel::KEYSTORE),
+        KeyParameter::new(KeyParameterValue::KeySize(256), SecurityLevel::KEYSTORE),
+        KeyParameter::new(KeyParameterValue::EcCurve(EcCurve::P_256), SecurityLevel::KEYSTORE),
+        KeyParameter::new(
+            KeyParameterValue::HardwareAuthenticatorType(HardwareAuthenticatorType::FINGERPRINT),
+            SecurityLevel::KEYSTORE,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::KeyOrigin(KeyOrigin::GENERATED),
+            SecurityLevel::KEYSTORE,
+        ),
+        KeyParameter::new(KeyParameterValue::OSVersion(110000), SecurityLevel::KEYSTORE),
+        KeyParameter::new(KeyParameterValue::OSPatchLevel(202101), SecurityLevel::KEYSTORE),
+        KeyParameter::new(KeyParameterValue::BootPatchLevel(20210105), SecurityLevel::KEYSTORE),
+        KeyParameter::new(KeyParameterValue::VendorPatchLevel(20210105), SecurityLevel::KEYSTORE),
+    ])
+}
+
+pub fn structured_test_params_cache() -> LegacyKeyCharacteristics {
+    LegacyKeyCharacteristics::Cache(vec![
+        KeyParameter::new(
+            KeyParameterValue::KeyPurpose(KeyPurpose::SIGN),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::KeyPurpose(KeyPurpose::VERIFY),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::Digest(Digest::SHA_2_256),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::UserSecureID(2100322049669824240),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::Algorithm(Algorithm::EC),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(KeyParameterValue::KeySize(256), SecurityLevel::TRUSTED_ENVIRONMENT),
+        KeyParameter::new(
+            KeyParameterValue::EcCurve(EcCurve::P_256),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::HardwareAuthenticatorType(HardwareAuthenticatorType::FINGERPRINT),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::KeyOrigin(KeyOrigin::GENERATED),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(KeyParameterValue::OSVersion(110000), SecurityLevel::TRUSTED_ENVIRONMENT),
+        KeyParameter::new(
+            KeyParameterValue::OSPatchLevel(202101),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::BootPatchLevel(20210105),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::VendorPatchLevel(20210105),
+            SecurityLevel::TRUSTED_ENVIRONMENT,
+        ),
+        KeyParameter::new(
+            KeyParameterValue::CreationDateTime(1607149002000),
+            SecurityLevel::KEYSTORE,
+        ),
+        KeyParameter::new(KeyParameterValue::UserID(0), SecurityLevel::KEYSTORE),
+    ])
+}
+
+// One encoded list of key parameters.
+pub static KEY_PARAMETERS: &[u8] = &[
+    0x00, 0x00, 0x00, 0x00, 0x0f, 0x00, 0x00, 0x00, 0x7c, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x20,
+    0x02, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x20, 0x03, 0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x20,
+    0x04, 0x00, 0x00, 0x00, 0xf6, 0x01, 0x00, 0xa0, 0xf0, 0x7e, 0x7d, 0xb4, 0xc6, 0xd7, 0x25, 0x1d,
+    0x02, 0x00, 0x00, 0x10, 0x03, 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x30, 0x00, 0x01, 0x00, 0x00,
+    0x0a, 0x00, 0x00, 0x10, 0x01, 0x00, 0x00, 0x00, 0x2d, 0x01, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00,
+    0xf8, 0x01, 0x00, 0x10, 0x02, 0x00, 0x00, 0x00, 0xbe, 0x02, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00,
+    0xc1, 0x02, 0x00, 0x30, 0xb0, 0xad, 0x01, 0x00, 0xc2, 0x02, 0x00, 0x30, 0x75, 0x15, 0x03, 0x00,
+    0xcf, 0x02, 0x00, 0x30, 0xb9, 0x61, 0x34, 0x01, 0xce, 0x02, 0x00, 0x30, 0xb9, 0x61, 0x34, 0x01,
+    0x30, 0x01, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00,
+];
+
 pub static REAL_LEGACY_BLOB: &[u8] = &[
     0x03, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
@@ -164,6 +272,24 @@
     0x76, 0x04, 0x2a, 0x48, 0xd1, 0xa7, 0x59, 0xd1, 0x04, 0x5b, 0xb4, 0x8a, 0x09, 0x22, 0x13, 0x0c,
     0x94, 0xb6, 0x67, 0x7b, 0x39, 0x85, 0x28, 0x11,
 ];
+
+pub static SUPERKEY_IV: &[u8] = &[
+    0x9a, 0x81, 0x56, 0x7d, 0xf5, 0x86, 0x7c, 0x62, 0xd7, 0xf9, 0x26, 0x06, 0x00, 0x00, 0x00, 0x00,
+];
+
+pub static SUPERKEY_TAG: &[u8] = &[
+    0xde, 0x2a, 0xcb, 0xac, 0x98, 0x57, 0x2b, 0xe5, 0x57, 0x18, 0x78, 0x57, 0x6e, 0x10, 0x09, 0x84,
+];
+
+pub static SUPERKEY_SALT: &[u8] = &[
+    0x04, 0x5b, 0xb4, 0x8a, 0x09, 0x22, 0x13, 0x0c, 0x94, 0xb6, 0x67, 0x7b, 0x39, 0x85, 0x28, 0x11,
+];
+
+pub static SUPERKEY_PAYLOAD: &[u8] = &[
+    0xac, 0x6d, 0x13, 0xe6, 0xad, 0x2c, 0x89, 0x53, 0x1a, 0x99, 0xa5, 0x6c, 0x88, 0xe9, 0xeb, 0x5c,
+    0xef, 0x68, 0x5e, 0x5b, 0x53, 0xa8, 0xe7, 0xa2, 0x76, 0x04, 0x2a, 0x48, 0xd1, 0xa7, 0x59, 0xd1,
+];
+
 pub static USRPKEY_AUTHBOUND: &[u8] = &[
     0x03, 0x04, 0x04, 0x00, 0x1c, 0x34, 0x87, 0x6f, 0xc8, 0x35, 0x0d, 0x34, 0x88, 0x59, 0xbc, 0xf5,
     0x00, 0x00, 0x00, 0x00, 0x62, 0xe3, 0x38, 0x2d, 0xd0, 0x58, 0x40, 0xc1, 0xb0, 0xf2, 0x4a, 0xdd,
@@ -203,6 +329,52 @@
     0xaf, 0x17, 0x2f, 0x21, 0x07, 0xea, 0x61, 0xff, 0x73, 0x08, 0x50, 0xb2, 0x19, 0xe8, 0x23, 0x1b,
     0x83, 0x42, 0xdd, 0x4e, 0x6d,
 ];
+
+pub static USRPKEY_AUTHBOUND_IV: &[u8] = &[
+    0x1c, 0x34, 0x87, 0x6f, 0xc8, 0x35, 0x0d, 0x34, 0x88, 0x59, 0xbc, 0xf5, 0x00, 0x00, 0x00, 0x00,
+];
+
+pub static USRPKEY_AUTHBOUND_TAG: &[u8] = &[
+    0x62, 0xe3, 0x38, 0x2d, 0xd0, 0x58, 0x40, 0xc1, 0xb0, 0xf2, 0x4a, 0xdd, 0xf7, 0x81, 0x67, 0x0b,
+];
+
+pub static USRPKEY_AUTHBOUND_ENC_PAYLOAD: &[u8] = &[
+    0x05, 0xb2, 0x5a, 0x1d, 0x1b, 0x25, 0x19, 0x48, 0xbf, 0x76, 0x0b, 0x37, 0x8c, 0x60, 0x52, 0xea,
+    0x30, 0x2a, 0x2c, 0x89, 0x99, 0x95, 0x57, 0x5c, 0xec, 0x62, 0x3c, 0x08, 0x1a, 0xc6, 0x65, 0xf9,
+    0xad, 0x24, 0x99, 0xf0, 0x5c, 0x44, 0xa0, 0xea, 0x9a, 0x60, 0xa2, 0xef, 0xf5, 0x27, 0x50, 0xba,
+    0x9c, 0xef, 0xa6, 0x08, 0x88, 0x4b, 0x0f, 0xfe, 0x5d, 0x41, 0xac, 0xba, 0xef, 0x9d, 0xa4, 0xb7,
+    0x72, 0xd3, 0xc8, 0x11, 0x92, 0x06, 0xf6, 0x26, 0xdf, 0x90, 0xe2, 0x66, 0x89, 0xf3, 0x85, 0x16,
+    0x4a, 0xdf, 0x7f, 0xac, 0x94, 0x4a, 0x1c, 0xce, 0x18, 0xee, 0xf4, 0x1f, 0x8e, 0xd6, 0xaf, 0xfd,
+    0x1d, 0xe5, 0x80, 0x4a, 0x6b, 0xbf, 0x91, 0xe2, 0x36, 0x1d, 0xb3, 0x53, 0x12, 0xfd, 0xc9, 0x0b,
+    0xa6, 0x69, 0x00, 0x45, 0xcb, 0x4c, 0x40, 0x6b, 0x70, 0xcb, 0xd2, 0xa0, 0x44, 0x0b, 0x4b, 0xec,
+    0xd6, 0x4f, 0x6f, 0x64, 0x37, 0xa7, 0xc7, 0x25, 0x54, 0xf4, 0xac, 0x6b, 0x34, 0x53, 0xea, 0x4e,
+    0x56, 0x49, 0xba, 0xf4, 0x1e, 0xc6, 0x52, 0x8f, 0xf4, 0x85, 0xe7, 0xb5, 0xaf, 0x49, 0x68, 0xb3,
+    0xb8, 0x7d, 0x63, 0xfc, 0x6e, 0x83, 0xa0, 0xf3, 0x91, 0x04, 0x80, 0xfd, 0xc5, 0x54, 0x7e, 0x92,
+    0x1a, 0x87, 0x2c, 0x6e, 0xa6, 0x29, 0xb9, 0x1e, 0x3f, 0xef, 0x30, 0x12, 0x7b, 0x2f, 0xa2, 0x16,
+    0x61, 0x8a, 0xcf, 0x14, 0x2d, 0x62, 0x98, 0x15, 0xae, 0x3b, 0xe6, 0x08, 0x1e, 0xb1, 0xf1, 0x21,
+    0xb0, 0x50, 0xc0, 0x4b, 0x81, 0x71, 0x29, 0xe7, 0x86, 0xbf, 0x29, 0xe1, 0xeb, 0xfe, 0xbc, 0x11,
+    0x3c, 0xc6, 0x15, 0x47, 0x9b, 0x41, 0x84, 0x61, 0x33, 0xbf, 0xca, 0xfe, 0x24, 0x92, 0x9e, 0x70,
+    0x26, 0x36, 0x46, 0xca, 0xfe, 0xd3, 0x5a, 0x1d, 0x9e, 0x30, 0x19, 0xbd, 0x26, 0x49, 0xb4, 0x90,
+    0x0c, 0x8d, 0xa2, 0x28, 0xa6, 0x24, 0x62, 0x6b, 0xe2, 0xfa, 0xe0, 0x53, 0xaa, 0x01, 0xeb, 0xaa,
+    0x41, 0x2b, 0xcb, 0xb1, 0x08, 0x66, 0x9d, 0x21, 0x2d, 0x2a, 0x47, 0x44, 0xee, 0xd5, 0x06, 0xe3,
+    0x4a, 0xb9, 0x3f, 0xcd, 0x78, 0x67, 0x89, 0x5b, 0xf7, 0x51, 0xc0, 0xc4, 0xa9, 0x68, 0xee, 0x44,
+    0x9c, 0x47, 0xa4, 0xbd, 0x6f, 0x7b, 0xdd, 0x64, 0xa8, 0xc7, 0x1e, 0x77, 0x1d, 0x68, 0x87, 0xaa,
+    0xae, 0x3c, 0xfc, 0x58, 0xb6, 0x3c, 0xcf, 0x58, 0xd0, 0x10, 0xaa, 0xef, 0xf0, 0x98, 0x67, 0x14,
+    0x29, 0x4d, 0x40, 0x8b, 0xe5, 0xb1, 0xdf, 0x7f, 0x40, 0xb1, 0xd8, 0xea, 0x6c, 0xa8, 0xf7, 0x64,
+    0xed, 0x02, 0x8d, 0xe7, 0x93, 0xfe, 0x79, 0x9a, 0x88, 0x62, 0x4f, 0xd0, 0x8a, 0x80, 0x36, 0x42,
+    0x0a, 0xf1, 0xa2, 0x0e, 0x30, 0x39, 0xbd, 0x26, 0x1d, 0xd4, 0xf1, 0xc8, 0x6e, 0xdd, 0xc5, 0x41,
+    0x29, 0xd8, 0xc1, 0x9e, 0x24, 0xf0, 0x25, 0x07, 0x05, 0x06, 0xc5, 0x08, 0xe3, 0x02, 0x2b, 0xe1,
+    0x40, 0xc5, 0x67, 0xd2, 0x82, 0x96, 0x20, 0x80, 0xcf, 0x87, 0x3a, 0xc6, 0xb0, 0xbe, 0xcc, 0xbb,
+    0x5a, 0x01, 0xab, 0xdd, 0x00, 0xc7, 0x0e, 0x7b, 0x02, 0x35, 0x27, 0xf4, 0x70, 0xfe, 0xd1, 0x19,
+    0x6a, 0x64, 0x23, 0x9d, 0xba, 0xe9, 0x1d, 0x76, 0x90, 0xfe, 0x7f, 0xd6, 0xb5, 0xa0, 0xe7, 0xb9,
+    0xf3, 0x56, 0x82, 0x8e, 0x57, 0x35, 0xf2, 0x69, 0xce, 0x52, 0xac, 0xc2, 0xf6, 0x5e, 0xb6, 0x54,
+    0x95, 0x83, 0x3b, 0x9f, 0x48, 0xbb, 0x04, 0x06, 0xac, 0x55, 0xa9, 0xb9, 0xa3, 0xe7, 0x89, 0x6e,
+    0x5c, 0x3a, 0x08, 0x67, 0x00, 0x8f, 0x1e, 0x26, 0x1b, 0x4d, 0x8a, 0xa6, 0x17, 0xa0, 0xa6, 0x18,
+    0xe6, 0x31, 0x43, 0x15, 0xb8, 0x7f, 0x9e, 0xf5, 0x78, 0x58, 0x98, 0xb1, 0x8c, 0xf5, 0x22, 0x42,
+    0x33, 0xc0, 0x42, 0x72, 0x4f, 0xce, 0x9f, 0x31, 0xaf, 0x17, 0x2f, 0x21, 0x07, 0xea, 0x61, 0xff,
+    0x73, 0x08, 0x50, 0xb2, 0x19, 0xe8, 0x23, 0x1b, 0x83, 0x42, 0xdd, 0x4e, 0x6d,
+];
+
 pub static USRPKEY_AUTHBOUND_CHR: &[u8] = &[
     0x03, 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
diff --git a/keystore2/src/legacy_importer.rs b/keystore2/src/legacy_importer.rs
index 3f37b14..81fb06c 100644
--- a/keystore2/src/legacy_importer.rs
+++ b/keystore2/src/legacy_importer.rs
@@ -14,18 +14,19 @@
 
 //! This module acts as a bridge between the legacy key database and the keystore2 database.
 
-use crate::key_parameter::KeyParameterValue;
-use crate::legacy_blob::BlobValue;
-use crate::utils::{uid_to_android_user, watchdog as wd};
-use crate::{async_task::AsyncTask, legacy_blob::LegacyBlobLoader};
-use crate::{database::KeyType, error::Error};
-use crate::{
-    database::{
-        BlobMetaData, BlobMetaEntry, CertificateInfo, DateTime, EncryptedBy, KeyMetaData,
-        KeyMetaEntry, KeystoreDB, Uuid, KEYSTORE_UUID,
-    },
-    super_key::USER_SUPER_KEY,
+use crate::database::{
+    BlobInfo, BlobMetaData, BlobMetaEntry, CertificateInfo, DateTime, EncryptedBy, KeyMetaData,
+    KeyMetaEntry, KeyType, KeystoreDB, Uuid, KEYSTORE_UUID,
 };
+use crate::error::{map_km_error, Error};
+use crate::key_parameter::{KeyParameter, KeyParameterValue};
+use crate::legacy_blob::{self, Blob, BlobValue, LegacyKeyCharacteristics};
+use crate::super_key::USER_SUPER_KEY;
+use crate::utils::{
+    key_characteristics_to_internal, uid_to_android_user, upgrade_keyblob_if_required_with,
+    watchdog as wd, AesGcm,
+};
+use crate::{async_task::AsyncTask, legacy_blob::LegacyBlobLoader};
 use android_hardware_security_keymint::aidl::android::hardware::security::keymint::SecurityLevel::SecurityLevel;
 use android_system_keystore2::aidl::android::system::keystore2::{
     Domain::Domain, KeyDescriptor::KeyDescriptor, ResponseCode::ResponseCode,
@@ -279,6 +280,116 @@
         result
     }
 
+    /// This function behaves exactly like with_try_import unless the src_key has an encrypted
+    /// component (other than the key blob itself [1]) and super_key is None.
+    /// In that case the files belonging to the src_key will be renamed to be moved to the
+    /// namespace indicated by dst_key. The destination domain must be in Domain::APP.
+    ///
+    /// [1] Components that cannot be encrypted with the super key in keystore2 include the
+    /// characteristics file, which was encrypted before Android Q, and certificate entries
+    /// added by KeyChain before Android Q.
+    pub fn with_try_import_or_migrate_namespaces<F, T>(
+        &self,
+        src: (u32, &KeyDescriptor),
+        dest: (u32, &KeyDescriptor),
+        super_key: Option<Arc<dyn AesGcm + Send + Sync>>,
+        has_migrate_any_permission: bool,
+        key_accessor: F,
+    ) -> Result<Option<T>>
+    where
+        F: Fn() -> Result<T>,
+    {
+        let _wp = wd::watch_millis("LegacyImporter::with_try_import_or_migrate_namespaces", 500);
+
+        let (src_uid, src_key) = src;
+        let (dest_uid, dest_key) = dest;
+
+        // Access the key and return on success.
+        match key_accessor() {
+            Ok(result) => return Ok(Some(result)),
+            Err(e) => {
+                if e.root_cause().downcast_ref::<Error>()
+                    != Some(&Error::Rc(ResponseCode::KEY_NOT_FOUND))
+                {
+                    return Err(e);
+                }
+            }
+        }
+
+        // Filter inputs. We can only load legacy app domain keys as well
+        // as the SELINUX WIFI_NAMESPACE, which will be populated from AID_WIFI.
+        let src_uid = match src_key {
+            KeyDescriptor { domain: Domain::APP, alias: Some(_), .. } => src_uid,
+            KeyDescriptor { domain: Domain::SELINUX, nspace, alias: Some(_), .. } => {
+                match *nspace {
+                    Self::WIFI_NAMESPACE => Self::AID_WIFI,
+                    _ => {
+                        return Err(Error::Rc(ResponseCode::KEY_NOT_FOUND))
+                            .context(format!("No legacy keys for namespace {}", nspace))
+                    }
+                }
+            }
+            _ => {
+                return Err(Error::Rc(ResponseCode::KEY_NOT_FOUND))
+                    .context("No legacy keys for key descriptor.")
+            }
+        };
+
+        let dest_uid = match dest_key {
+            KeyDescriptor { domain: Domain::APP, alias: Some(_), .. } => Some(dest_uid),
+            KeyDescriptor { domain: Domain::SELINUX, alias: Some(_), .. } => {
+                // Domain::SELINUX cannot be migrated in place, but we cannot fail at this point
+                // because the import may succeed at which point the actual migration will
+                // be performed by the caller.
+                None
+            }
+            _ => {
+                return Err(Error::Rc(ResponseCode::KEY_NOT_FOUND))
+                    .context("No legacy keys for key descriptor.")
+            }
+        };
+
+        let src_key_clone = src_key.clone();
+        let dest_key_clone = dest_key.clone();
+        let result = self.do_serialized(move |importer_state| {
+            let super_key = super_key.map(|sk| -> Arc<dyn AesGcm> { sk });
+            match (
+                importer_state.check_and_import(src_uid, src_key_clone.clone(), super_key),
+                dest_uid,
+            ) {
+                // The import into the database was successful. Return Ok(true)
+                (Ok(()), _) => Ok(true),
+                // The import failed because a certificate and/or characteristics
+                // file was encrypted and no super_key was available. Migration within the
+                // legacy database is attempted and Ok(false) is returned on success.
+                (Err(e), Some(dest_uid))
+                    if has_migrate_any_permission
+                        && e.root_cause().downcast_ref::<Error>()
+                            == Some(&Error::Rc(ResponseCode::LOCKED)) =>
+                {
+                    importer_state
+                        .migrate_namespaces(src_uid, dest_uid, src_key_clone, dest_key_clone)
+                        .map(|_| false)
+                }
+                (Err(e), _) => Err(e),
+            }
+        });
+
+        match result {
+            None => {
+                Err(Error::Rc(ResponseCode::KEY_NOT_FOUND)).context("Legacy database is empty.")
+            }
+
+            Some(Ok(true)) => {
+                // After successful import try again.
+                key_accessor().map(|v| Some(v))
+            }
+            // The entry was successfully migrated within the legacy database.
+            Some(Ok(false)) => Ok(None),
+            Some(Err(e)) => Err(e),
+        }
+    }
+
     /// Runs the key_accessor function and returns its result. If it returns an error and the
     /// root cause was KEY_NOT_FOUND, tries to import a key with the given parameters from
     /// the legacy database to the new database and runs the key_accessor function again if
@@ -287,6 +398,7 @@
         &self,
         key: &KeyDescriptor,
         caller_uid: u32,
+        super_key: Option<Arc<dyn AesGcm + Send + Sync>>,
         key_accessor: F,
     ) -> Result<T>
     where
@@ -323,8 +435,10 @@
         };
 
         let key_clone = key.clone();
-        let result = self
-            .do_serialized(move |importer_state| importer_state.check_and_import(uid, key_clone));
+        let result = self.do_serialized(move |importer_state| {
+            let super_key = super_key.map(|sk| -> Arc<dyn AesGcm> { sk });
+            importer_state.check_and_import(uid, key_clone, super_key)
+        });
 
         if let Some(result) = result {
             result?;
@@ -430,9 +544,199 @@
             .context("In list_uid: Trying to list legacy entries.")
     }
 
+    fn migrate_namespaces(
+        &mut self,
+        src_uid: u32,
+        dest_uid: u32,
+        src_key: KeyDescriptor,
+        dest_key: KeyDescriptor,
+    ) -> Result<()> {
+        let src_alias = src_key.alias.ok_or_else(|| {
+            anyhow::anyhow!(Error::sys()).context(
+                "In legacy_migrator::migrate_namespace: src_key.alias must be Some because \
+                 our caller must not have called us otherwise.",
+            )
+        })?;
+
+        if dest_key.domain != Domain::APP {
+            return Err(Error::Rc(ResponseCode::INVALID_ARGUMENT)).context(
+                "In legacy_migrator::migrate_namespace: \
+                 Legacy in-place migration to SELinux namespace is not supported.",
+            );
+        }
+
+        let dest_alias = dest_key.alias.ok_or_else(|| {
+            anyhow::anyhow!(Error::sys()).context(concat!(
+                "In legacy_migrator::migrate_namespace: dest_key.alias must be Some because ",
+                "our caller must not have called us otherwise."
+            ))
+        })?;
+
+        self.legacy_loader
+            .move_keystore_entry(src_uid, dest_uid, &src_alias, &dest_alias)
+            .context("In legacy_migrator::migrate_namespace: Moving key entry files.")
+    }
+
+    /// Checks if the key can potentially be unlocked. And deletes the key entry otherwise.
+    /// If the super_key has already been imported, the super key database id is returned.
+    fn get_super_key_id_check_unlockable_or_delete(
+        &mut self,
+        uid: u32,
+        alias: &str,
+    ) -> Result<i64> {
+        let user_id = uid_to_android_user(uid);
+
+        match self
+            .db
+            .load_super_key(&USER_SUPER_KEY, user_id)
+            .context("In get_super_key_id_check_unlockable_or_delete: Failed to load super key")?
+        {
+            Some((_, entry)) => Ok(entry.id()),
+            None => {
+                // This might be the first time we access the super key,
+                // and it may not have been imported. We cannot import
+                // the legacy super_key key now, because we need to reencrypt
+                // it which we cannot do if we are not unlocked, which we are
+                // not because otherwise the key would have been imported.
+                // We can check though if the key exists. If it does,
+                // we can return Locked. Otherwise, we can delete the
+                // key and return NotFound, because the key will never
+                // be unlocked again.
+                if self.legacy_loader.has_super_key(user_id) {
+                    Err(Error::Rc(ResponseCode::LOCKED)).context(
+                        "In get_super_key_id_check_unlockable_or_delete: \
+                         Cannot import super key of this key while user is locked.",
+                    )
+                } else {
+                    self.legacy_loader.remove_keystore_entry(uid, alias).context(
+                        "In get_super_key_id_check_unlockable_or_delete: \
+                         Trying to remove obsolete key.",
+                    )?;
+                    Err(Error::Rc(ResponseCode::KEY_NOT_FOUND))
+                        .context("In get_super_key_id_check_unlockable_or_delete: Obsolete key.")
+                }
+            }
+        }
+    }
+
+    fn characteristics_file_to_cache(
+        &mut self,
+        km_blob_params: Option<(Blob, LegacyKeyCharacteristics)>,
+        super_key: &Option<Arc<dyn AesGcm>>,
+        uid: u32,
+        alias: &str,
+    ) -> Result<(Option<(Blob, Vec<KeyParameter>)>, Option<(LegacyBlob<'static>, BlobMetaData)>)>
+    {
+        let (km_blob, params) = match km_blob_params {
+            Some((km_blob, LegacyKeyCharacteristics::File(params))) => (km_blob, params),
+            Some((km_blob, LegacyKeyCharacteristics::Cache(params))) => {
+                return Ok((Some((km_blob, params)), None))
+            }
+            None => return Ok((None, None)),
+        };
+
+        let km_uuid = self
+            .get_km_uuid(km_blob.is_strongbox())
+            .context("In characteristics_file_to_cache: Trying to get KM UUID")?;
+
+        let blob = match (&km_blob.value(), super_key.as_ref()) {
+            (BlobValue::Encrypted { iv, tag, data }, Some(super_key)) => {
+                let blob = super_key
+                    .decrypt(data, iv, tag)
+                    .context("In characteristics_file_to_cache: Decryption failed.")?;
+                LegacyBlob::ZVec(blob)
+            }
+            (BlobValue::Encrypted { .. }, None) => {
+                return Err(Error::Rc(ResponseCode::LOCKED)).context(
+                    "In characteristics_file_to_cache: Oh uh, so close. \
+                     This ancient key cannot be imported unless the user is unlocked.",
+                );
+            }
+            (BlobValue::Decrypted(data), _) => LegacyBlob::Ref(data),
+            _ => {
+                return Err(Error::sys())
+                    .context("In characteristics_file_to_cache: Unexpected blob type.")
+            }
+        };
+
+        let (km_params, upgraded_blob) = get_key_characteristics_without_app_data(&km_uuid, &*blob)
+            .context(
+                "In characteristics_file_to_cache: Failed to get key characteristics from device.",
+            )?;
+
+        let flags = km_blob.get_flags();
+
+        let (current_blob, superseded_blob) = if let Some(upgraded_blob) = upgraded_blob {
+            match (km_blob.take_value(), super_key.as_ref()) {
+                (BlobValue::Encrypted { iv, tag, data }, Some(super_key)) => {
+                    let super_key_id =
+                        self.get_super_key_id_check_unlockable_or_delete(uid, alias).context(
+                            "In characteristics_file_to_cache: \
+                             How is there a super key but no super key id?",
+                        )?;
+
+                    let mut superseded_metadata = BlobMetaData::new();
+                    superseded_metadata.add(BlobMetaEntry::Iv(iv.to_vec()));
+                    superseded_metadata.add(BlobMetaEntry::AeadTag(tag.to_vec()));
+                    superseded_metadata
+                        .add(BlobMetaEntry::EncryptedBy(EncryptedBy::KeyId(super_key_id)));
+                    superseded_metadata.add(BlobMetaEntry::KmUuid(km_uuid));
+                    let superseded_blob = (LegacyBlob::Vec(data), superseded_metadata);
+
+                    let (data, iv, tag) = super_key.encrypt(&upgraded_blob).context(
+                        "In characteristics_file_to_cache: \
+                         Failed to encrypt upgraded key blob.",
+                    )?;
+                    (
+                        Blob::new(flags, BlobValue::Encrypted { data, iv, tag }),
+                        Some(superseded_blob),
+                    )
+                }
+                (BlobValue::Encrypted { .. }, None) => {
+                    return Err(Error::sys()).context(
+                        "In characteristics_file_to_cache: This should not be reachable. \
+                         The blob could not have been decrypted above.",
+                    );
+                }
+                (BlobValue::Decrypted(data), _) => {
+                    let mut superseded_metadata = BlobMetaData::new();
+                    superseded_metadata.add(BlobMetaEntry::KmUuid(km_uuid));
+                    let superseded_blob = (LegacyBlob::ZVec(data), superseded_metadata);
+                    (
+                        Blob::new(
+                            flags,
+                            BlobValue::Decrypted(upgraded_blob.try_into().context(
+                                "In characteristics_file_to_cache: \
+                             Failed to convert upgraded blob to ZVec.",
+                            )?),
+                        ),
+                        Some(superseded_blob),
+                    )
+                }
+                _ => {
+                    return Err(Error::sys()).context(
+                        "In characteristics_file_to_cache: This should not be reachable. \
+                         Any other variant should have resulted in a different error.",
+                    )
+                }
+            }
+        } else {
+            (km_blob, None)
+        };
+
+        let params =
+            augment_legacy_characteristics_file_with_key_characteristics(km_params, params);
+        Ok((Some((current_blob, params)), superseded_blob))
+    }
+
     /// This is a key import request that must run in the importer thread. This must
     /// be passed to do_serialized.
-    fn check_and_import(&mut self, uid: u32, mut key: KeyDescriptor) -> Result<()> {
+    fn check_and_import(
+        &mut self,
+        uid: u32,
+        mut key: KeyDescriptor,
+        super_key: Option<Arc<dyn AesGcm>>,
+    ) -> Result<()> {
         let alias = key.alias.clone().ok_or_else(|| {
             anyhow::anyhow!(Error::sys()).context(
                 "In check_and_import: Must be Some because \
@@ -451,49 +755,42 @@
         // If the key is not found in the cache, try to load from the legacy database.
         let (km_blob_params, user_cert, ca_cert) = self
             .legacy_loader
-            .load_by_uid_alias(uid, &alias, None)
+            .load_by_uid_alias(uid, &alias, &super_key)
+            .map_err(|e| {
+                if e.root_cause().downcast_ref::<legacy_blob::Error>()
+                    == Some(&legacy_blob::Error::LockedComponent)
+                {
+                    // There is no chance to succeed at this point. We just check if there is
+                    // a super key so that this entry might be unlockable in the future.
+                    // If not the entry will be deleted and KEY_NOT_FOUND is returned.
+                    // If a super key id was returned we still have to return LOCKED but the key
+                    // may be imported when the user unlocks the device.
+                    self.get_super_key_id_check_unlockable_or_delete(uid, &alias)
+                        .and_then::<i64, _>(|_| {
+                            Err(Error::Rc(ResponseCode::LOCKED))
+                                .context("Super key present but locked.")
+                        })
+                        .unwrap_err()
+                } else {
+                    e
+                }
+            })
             .context("In check_and_import: Trying to load legacy blob.")?;
+
+        let (km_blob_params, superseded_blob) = self
+            .characteristics_file_to_cache(km_blob_params, &super_key, uid, &alias)
+            .context("In check_and_import: Trying to update legacy charateristics.")?;
+
         let result = match km_blob_params {
             Some((km_blob, params)) => {
                 let is_strongbox = km_blob.is_strongbox();
+
                 let (blob, mut blob_metadata) = match km_blob.take_value() {
                     BlobValue::Encrypted { iv, tag, data } => {
                         // Get super key id for user id.
-                        let user_id = uid_to_android_user(uid as u32);
-
-                        let super_key_id = match self
-                            .db
-                            .load_super_key(&USER_SUPER_KEY, user_id)
-                            .context("In check_and_import: Failed to load super key")?
-                        {
-                            Some((_, entry)) => entry.id(),
-                            None => {
-                                // This might be the first time we access the super key,
-                                // and it may not have been imported. We cannot import
-                                // the legacy super_key key now, because we need to reencrypt
-                                // it which we cannot do if we are not unlocked, which we are
-                                // not because otherwise the key would have been imported.
-                                // We can check though if the key exists. If it does,
-                                // we can return Locked. Otherwise, we can delete the
-                                // key and return NotFound, because the key will never
-                                // be unlocked again.
-                                if self.legacy_loader.has_super_key(user_id) {
-                                    return Err(Error::Rc(ResponseCode::LOCKED)).context(concat!(
-                                        "In check_and_import: Cannot import super key of this ",
-                                        "key while user is locked."
-                                    ));
-                                } else {
-                                    self.legacy_loader.remove_keystore_entry(uid, &alias).context(
-                                        concat!(
-                                            "In check_and_import: ",
-                                            "Trying to remove obsolete key."
-                                        ),
-                                    )?;
-                                    return Err(Error::Rc(ResponseCode::KEY_NOT_FOUND))
-                                        .context("In check_and_import: Obsolete key.");
-                                }
-                            }
-                        };
+                        let super_key_id = self
+                            .get_super_key_id_check_unlockable_or_delete(uid, &alias)
+                            .context("In check_and_import: Failed to get super key id.")?;
 
                         let mut blob_metadata = BlobMetaData::new();
                         blob_metadata.add(BlobMetaEntry::Iv(iv.to_vec()));
@@ -519,13 +816,18 @@
                     .context("In check_and_import: Trying to make creation time.")?;
                 metadata.add(KeyMetaEntry::CreationDate(creation_date));
 
+                let blob_info = BlobInfo::new_with_superseded(
+                    &blob,
+                    &blob_metadata,
+                    superseded_blob.as_ref().map(|(b, m)| (&**b, m)),
+                );
                 // Store legacy key in the database.
                 self.db
                     .store_new_key(
                         &key,
                         KeyType::Client,
                         &params,
-                        &(&blob, &blob_metadata),
+                        &blob_info,
                         &CertificateInfo::new(user_cert, ca_cert),
                         &metadata,
                         &km_uuid,
@@ -635,13 +937,17 @@
         {
             let (km_blob_params, _, _) = self
                 .legacy_loader
-                .load_by_uid_alias(uid, &alias, None)
+                .load_by_uid_alias(uid, &alias, &None)
                 .context("In bulk_delete: Trying to load legacy blob.")?;
 
             // Determine if the key needs special handling to be deleted.
             let (need_gc, is_super_encrypted) = km_blob_params
                 .as_ref()
                 .map(|(blob, params)| {
+                    let params = match params {
+                        LegacyKeyCharacteristics::Cache(params)
+                        | LegacyKeyCharacteristics::File(params) => params,
+                    };
                     (
                         params.iter().any(|kp| {
                             KeyParameterValue::RollbackResistance == *kp.key_parameter_value()
@@ -714,18 +1020,68 @@
     }
 }
 
-enum LegacyBlob {
+enum LegacyBlob<'a> {
     Vec(Vec<u8>),
     ZVec(ZVec),
+    Ref(&'a [u8]),
 }
 
-impl Deref for LegacyBlob {
+impl Deref for LegacyBlob<'_> {
     type Target = [u8];
 
     fn deref(&self) -> &Self::Target {
         match self {
             Self::Vec(v) => v,
             Self::ZVec(v) => v,
+            Self::Ref(v) => v,
         }
     }
 }
+
+/// This function takes two KeyParameter lists. The first is assumed to have been retrieved from the
+/// KM back end using km_dev.getKeyCharacteristics. The second is assumed to have been retrieved
+/// from a legacy key characteristics file (not cache) as used in Android P and older. The function
+/// augments the former with entries from the latter only if no equivalent entry is present ignoring.
+/// the security level of enforcement. All entries in the latter are assumed to have security level
+/// KEYSTORE.
+fn augment_legacy_characteristics_file_with_key_characteristics<T>(
+    mut from_km: Vec<KeyParameter>,
+    legacy: T,
+) -> Vec<KeyParameter>
+where
+    T: IntoIterator<Item = KeyParameter>,
+{
+    for legacy_kp in legacy.into_iter() {
+        if !from_km
+            .iter()
+            .any(|km_kp| km_kp.key_parameter_value() == legacy_kp.key_parameter_value())
+        {
+            from_km.push(legacy_kp);
+        }
+    }
+    from_km
+}
+
+/// Attempts to retrieve the key characteristics for the given blob from the KM back end with the
+/// given UUID. It may upgrade the key blob in the process. In that case the upgraded blob is
+/// returned as the second tuple member.
+fn get_key_characteristics_without_app_data(
+    uuid: &Uuid,
+    blob: &[u8],
+) -> Result<(Vec<KeyParameter>, Option<Vec<u8>>)> {
+    let (km_dev, _) = crate::globals::get_keymint_dev_by_uuid(uuid)
+        .with_context(|| format!("In foo: Trying to get km device for id {:?}", uuid))?;
+
+    let (characteristics, upgraded_blob) = upgrade_keyblob_if_required_with(
+        &*km_dev,
+        blob,
+        &[],
+        |blob| {
+            let _wd = wd::watch_millis("In foo: Calling GetKeyCharacteristics.", 500);
+            map_km_error(km_dev.getKeyCharacteristics(blob, &[], &[]))
+        },
+        |_| Ok(()),
+    )
+    .context("In foo.")?;
+    Ok((key_characteristics_to_internal(characteristics), upgraded_blob))
+}
diff --git a/keystore2/src/maintenance.rs b/keystore2/src/maintenance.rs
index 71f43d6..0d637d8 100644
--- a/keystore2/src/maintenance.rs
+++ b/keystore2/src/maintenance.rs
@@ -23,7 +23,8 @@
 use crate::permission::{KeyPerm, KeystorePerm};
 use crate::super_key::{SuperKeyManager, UserState};
 use crate::utils::{
-    check_key_permission, check_keystore_permission, list_key_entries, watchdog as wd,
+    check_key_permission, check_keystore_permission, list_key_entries, uid_to_android_user,
+    watchdog as wd,
 };
 use android_hardware_security_keymint::aidl::android::hardware::security::keymint::{
     IKeyMintDevice::IKeyMintDevice, SecurityLevel::SecurityLevel,
@@ -255,34 +256,55 @@
             }
         };
 
-        DB.with(|db| {
-            let (key_id_guard, _) = LEGACY_IMPORTER
-                .with_try_import(source, src_uid, || {
-                    db.borrow_mut().load_key_entry(
-                        source,
-                        KeyType::Client,
-                        KeyEntryLoadBits::NONE,
-                        src_uid,
-                        |k, av| {
-                            if migrate_any_key_permission {
-                                Ok(())
-                            } else {
-                                check_key_permission(KeyPerm::Use, k, &av)?;
-                                check_key_permission(KeyPerm::Delete, k, &av)?;
-                                check_key_permission(KeyPerm::Grant, k, &av)
-                            }
-                        },
-                    )
-                })
-                .context("In migrate_key_namespace: Failed to load key blob.")?;
+        let user_id = uid_to_android_user(dest_uid);
 
-            db.borrow_mut().migrate_key_namespace(key_id_guard, destination, dest_uid, |k| {
-                if migrate_any_key_permission {
-                    Ok(())
-                } else {
-                    check_key_permission(KeyPerm::Rebind, k, &None)
-                }
-            })
+        if user_id != uid_to_android_user(src_uid)
+            && (source.domain == Domain::APP || destination.domain == Domain::APP)
+        {
+            return Err(Error::sys()).context(
+                "In migrate_key_namespace: Keys cannot be migrated across android users.",
+            );
+        }
+
+        let super_key = SUPER_KEY.read().unwrap().get_per_boot_key_by_user_id(user_id);
+
+        DB.with(|db| {
+            if let Some((key_id_guard, _)) = LEGACY_IMPORTER
+                .with_try_import_or_migrate_namespaces(
+                    (src_uid, source),
+                    (dest_uid, destination),
+                    super_key,
+                    migrate_any_key_permission,
+                    || {
+                        db.borrow_mut().load_key_entry(
+                            source,
+                            KeyType::Client,
+                            KeyEntryLoadBits::NONE,
+                            src_uid,
+                            |k, av| {
+                                if migrate_any_key_permission {
+                                    Ok(())
+                                } else {
+                                    check_key_permission(KeyPerm::Use, k, &av)?;
+                                    check_key_permission(KeyPerm::Delete, k, &av)?;
+                                    check_key_permission(KeyPerm::Grant, k, &av)
+                                }
+                            },
+                        )
+                    },
+                )
+                .context("In migrate_key_namespace: Failed to load key blob.")?
+            {
+                db.borrow_mut().migrate_key_namespace(key_id_guard, destination, dest_uid, |k| {
+                    if migrate_any_key_permission {
+                        Ok(())
+                    } else {
+                        check_key_permission(KeyPerm::Rebind, k, &None)
+                    }
+                })
+            } else {
+                Ok(())
+            }
         })
     }
 
diff --git a/keystore2/src/raw_device.rs b/keystore2/src/raw_device.rs
index 0ee3db0..4ce9dce 100644
--- a/keystore2/src/raw_device.rs
+++ b/keystore2/src/raw_device.rs
@@ -16,8 +16,9 @@
 
 use crate::{
     database::{
-        BlobMetaData, BlobMetaEntry, CertificateInfo, DateTime, KeyEntry, KeyEntryLoadBits,
-        KeyIdGuard, KeyMetaData, KeyMetaEntry, KeyType, KeystoreDB, SubComponentType, Uuid,
+        BlobInfo, BlobMetaData, BlobMetaEntry, CertificateInfo, DateTime, KeyEntry,
+        KeyEntryLoadBits, KeyIdGuard, KeyMetaData, KeyMetaEntry, KeyType, KeystoreDB,
+        SubComponentType, Uuid,
     },
     error::{map_km_error, Error, ErrorCode},
     globals::get_keymint_device,
@@ -125,7 +126,7 @@
             key_desc,
             key_type,
             &key_parameters,
-            &(&creation_result.keyBlob, &blob_metadata),
+            &BlobInfo::new(&creation_result.keyBlob, &blob_metadata),
             &CertificateInfo::new(None, None),
             &key_metadata,
             &self.km_uuid,
diff --git a/keystore2/src/security_level.rs b/keystore2/src/security_level.rs
index eefbc20..4cf41c5 100644
--- a/keystore2/src/security_level.rs
+++ b/keystore2/src/security_level.rs
@@ -18,7 +18,7 @@
 use crate::audit_log::{
     log_key_deleted, log_key_generated, log_key_imported, log_key_integrity_violation,
 };
-use crate::database::{CertificateInfo, KeyIdGuard};
+use crate::database::{BlobInfo, CertificateInfo, KeyIdGuard};
 use crate::error::{self, map_km_error, map_or_log_err, Error, ErrorCode};
 use crate::globals::{DB, ENFORCEMENTS, LEGACY_IMPORTER, SUPER_KEY};
 use crate::key_parameter::KeyParameter as KsKeyParam;
@@ -182,7 +182,7 @@
                             &key,
                             KeyType::Client,
                             &key_parameters,
-                            &(&key_blob, &blob_metadata),
+                            &BlobInfo::new(&key_blob, &blob_metadata),
                             &cert_info,
                             &key_metadata,
                             &self.km_uuid,
@@ -243,9 +243,13 @@
                 )
             }
             _ => {
+                let super_key = SUPER_KEY
+                    .read()
+                    .unwrap()
+                    .get_per_boot_key_by_user_id(uid_to_android_user(caller_uid));
                 let (key_id_guard, mut key_entry) = DB
                     .with::<_, Result<(KeyIdGuard, KeyEntry)>>(|db| {
-                        LEGACY_IMPORTER.with_try_import(key, caller_uid, || {
+                        LEGACY_IMPORTER.with_try_import(key, caller_uid, super_key, || {
                             db.borrow_mut().load_key_entry(
                                 key,
                                 KeyType::Client,
@@ -721,9 +725,11 @@
         // Import_wrapped_key requires the rebind permission for the new key.
         check_key_permission(KeyPerm::Rebind, &key, &None).context("In import_wrapped_key.")?;
 
+        let super_key = SUPER_KEY.read().unwrap().get_per_boot_key_by_user_id(user_id);
+
         let (wrapping_key_id_guard, mut wrapping_key_entry) = DB
             .with(|db| {
-                LEGACY_IMPORTER.with_try_import(&key, caller_uid, || {
+                LEGACY_IMPORTER.with_try_import(&key, caller_uid, super_key, || {
                     db.borrow_mut().load_key_entry(
                         wrapping_key,
                         KeyType::Client,
@@ -829,7 +835,7 @@
     fn upgrade_keyblob_if_required_with<T, F>(
         &self,
         km_dev: &dyn IKeyMintDevice,
-        key_id_guard: Option<KeyIdGuard>,
+        mut key_id_guard: Option<KeyIdGuard>,
         key_blob: &KeyBlob,
         blob_metadata: &BlobMetaData,
         params: &[KeyParameter],
@@ -838,60 +844,42 @@
     where
         F: Fn(&[u8]) -> Result<T, Error>,
     {
-        match f(key_blob) {
-            Err(Error::Km(ErrorCode::KEY_REQUIRES_UPGRADE)) => {
-                let upgraded_blob = {
-                    let _wp = self.watch_millis(
-                        concat!(
-                            "In KeystoreSecurityLevel::upgrade_keyblob_if_required_with: ",
-                            "calling upgradeKey."
-                        ),
-                        500,
-                    );
-                    map_km_error(km_dev.upgradeKey(key_blob, params))
-                }
-                .context("In upgrade_keyblob_if_required_with: Upgrade failed.")?;
-
-                if let Some(kid) = key_id_guard {
+        let (v, upgraded_blob) = crate::utils::upgrade_keyblob_if_required_with(
+            km_dev,
+            key_blob,
+            params,
+            f,
+            |upgraded_blob| {
+                if key_id_guard.is_some() {
+                    // Unwrap cannot panic, because the is_some was true.
+                    let kid = key_id_guard.take().unwrap();
                     Self::store_upgraded_keyblob(
                         kid,
                         blob_metadata.km_uuid(),
                         key_blob,
-                        &upgraded_blob,
+                        upgraded_blob,
                     )
-                    .context(
-                        "In upgrade_keyblob_if_required_with: store_upgraded_keyblob failed",
-                    )?;
+                    .context("In upgrade_keyblob_if_required_with: store_upgraded_keyblob failed")
+                } else {
+                    Ok(())
                 }
+            },
+        )
+        .context("In KeystoreSecurityLevel::upgrade_keyblob_if_required_with.")?;
 
-                match f(&upgraded_blob) {
-                    Ok(v) => Ok((v, Some(upgraded_blob))),
-                    Err(e) => Err(e).context(concat!(
+        // If no upgrade was needed, use the opportunity to reencrypt the blob if required
+        // and if the a key_id_guard is held. Note: key_id_guard can only be Some if no
+        // upgrade was performed above and if one was given in the first place.
+        if key_blob.force_reencrypt() {
+            if let Some(kid) = key_id_guard {
+                Self::store_upgraded_keyblob(kid, blob_metadata.km_uuid(), key_blob, key_blob)
+                    .context(concat!(
                         "In upgrade_keyblob_if_required_with: ",
-                        "Failed to perform operation on second try."
-                    )),
-                }
-            }
-            result => {
-                if let Some(kid) = key_id_guard {
-                    if key_blob.force_reencrypt() {
-                        Self::store_upgraded_keyblob(
-                            kid,
-                            blob_metadata.km_uuid(),
-                            key_blob,
-                            key_blob,
-                        )
-                        .context(concat!(
-                            "In upgrade_keyblob_if_required_with: ",
-                            "store_upgraded_keyblob failed in forced reencrypt"
-                        ))?;
-                    }
-                }
-                result
-                    .map(|v| (v, None))
-                    .context("In upgrade_keyblob_if_required_with: Called closure failed.")
+                        "store_upgraded_keyblob failed in forced reencrypt"
+                    ))?;
             }
         }
+        Ok((v, upgraded_blob))
     }
 
     fn convert_storage_key_to_ephemeral(
diff --git a/keystore2/src/service.rs b/keystore2/src/service.rs
index 46bc8b0..79e7692 100644
--- a/keystore2/src/service.rs
+++ b/keystore2/src/service.rs
@@ -22,11 +22,11 @@
 use crate::security_level::KeystoreSecurityLevel;
 use crate::utils::{
     check_grant_permission, check_key_permission, check_keystore_permission,
-    key_parameters_to_authorizations, list_key_entries, watchdog as wd,
+    key_parameters_to_authorizations, list_key_entries, uid_to_android_user, watchdog as wd,
 };
 use crate::{
     database::Uuid,
-    globals::{create_thread_local_db, DB, LEGACY_BLOB_LOADER, LEGACY_IMPORTER},
+    globals::{create_thread_local_db, DB, LEGACY_BLOB_LOADER, LEGACY_IMPORTER, SUPER_KEY},
 };
 use crate::{database::KEYSTORE_UUID, permission};
 use crate::{
@@ -130,9 +130,13 @@
 
     fn get_key_entry(&self, key: &KeyDescriptor) -> Result<KeyEntryResponse> {
         let caller_uid = ThreadState::get_calling_uid();
+
+        let super_key =
+            SUPER_KEY.read().unwrap().get_per_boot_key_by_user_id(uid_to_android_user(caller_uid));
+
         let (key_id_guard, mut key_entry) = DB
             .with(|db| {
-                LEGACY_IMPORTER.with_try_import(key, caller_uid, || {
+                LEGACY_IMPORTER.with_try_import(key, caller_uid, super_key, || {
                     db.borrow_mut().load_key_entry(
                         key,
                         KeyType::Client,
@@ -182,8 +186,11 @@
         certificate_chain: Option<&[u8]>,
     ) -> Result<()> {
         let caller_uid = ThreadState::get_calling_uid();
+        let super_key =
+            SUPER_KEY.read().unwrap().get_per_boot_key_by_user_id(uid_to_android_user(caller_uid));
+
         DB.with::<_, Result<()>>(|db| {
-            let entry = match LEGACY_IMPORTER.with_try_import(key, caller_uid, || {
+            let entry = match LEGACY_IMPORTER.with_try_import(key, caller_uid, super_key, || {
                 db.borrow_mut().load_key_entry(
                     key,
                     KeyType::Client,
@@ -291,8 +298,11 @@
 
     fn delete_key(&self, key: &KeyDescriptor) -> Result<()> {
         let caller_uid = ThreadState::get_calling_uid();
+        let super_key =
+            SUPER_KEY.read().unwrap().get_per_boot_key_by_user_id(uid_to_android_user(caller_uid));
+
         DB.with(|db| {
-            LEGACY_IMPORTER.with_try_import(key, caller_uid, || {
+            LEGACY_IMPORTER.with_try_import(key, caller_uid, super_key, || {
                 db.borrow_mut().unbind_key(key, KeyType::Client, caller_uid, |k, av| {
                     check_key_permission(KeyPerm::Delete, k, &av).context("During delete_key.")
                 })
@@ -309,8 +319,11 @@
         access_vector: permission::KeyPermSet,
     ) -> Result<KeyDescriptor> {
         let caller_uid = ThreadState::get_calling_uid();
+        let super_key =
+            SUPER_KEY.read().unwrap().get_per_boot_key_by_user_id(uid_to_android_user(caller_uid));
+
         DB.with(|db| {
-            LEGACY_IMPORTER.with_try_import(key, caller_uid, || {
+            LEGACY_IMPORTER.with_try_import(key, caller_uid, super_key, || {
                 db.borrow_mut().grant(
                     key,
                     caller_uid,
diff --git a/keystore2/src/super_key.rs b/keystore2/src/super_key.rs
index 2fb4991..376d44a 100644
--- a/keystore2/src/super_key.rs
+++ b/keystore2/src/super_key.rs
@@ -28,8 +28,7 @@
     legacy_blob::LegacyBlobLoader,
     legacy_importer::LegacyImporter,
     raw_device::KeyMintDevice,
-    utils::watchdog as wd,
-    utils::AID_KEYSTORE,
+    utils::{watchdog as wd, AesGcm, AID_KEYSTORE},
 };
 use android_hardware_security_keymint::aidl::android::hardware::security::keymint::{
     Algorithm::Algorithm, BlockMode::BlockMode, HardwareAuthToken::HardwareAuthToken,
@@ -154,15 +153,22 @@
     reencrypt_with: Option<Arc<SuperKey>>,
 }
 
-impl SuperKey {
-    /// For most purposes `unwrap_key` handles decryption,
-    /// but legacy handling and some tests need to assume AES and decrypt directly.
-    pub fn aes_gcm_decrypt(&self, data: &[u8], iv: &[u8], tag: &[u8]) -> Result<ZVec> {
+impl AesGcm for SuperKey {
+    fn decrypt(&self, data: &[u8], iv: &[u8], tag: &[u8]) -> Result<ZVec> {
         if self.algorithm == SuperEncryptionAlgorithm::Aes256Gcm {
             aes_gcm_decrypt(data, iv, tag, &self.key)
-                .context("In aes_gcm_decrypt: decryption failed")
+                .context("In SuperKey::decrypt: Decryption failed.")
         } else {
-            Err(Error::sys()).context("In aes_gcm_decrypt: Key is not an AES key")
+            Err(Error::sys()).context("In SuperKey::decrypt: Key is not an AES key.")
+        }
+    }
+
+    fn encrypt(&self, plaintext: &[u8]) -> Result<(Vec<u8>, Vec<u8>, Vec<u8>)> {
+        if self.algorithm == SuperEncryptionAlgorithm::Aes256Gcm {
+            aes_gcm_encrypt(plaintext, &self.key)
+                .context("In SuperKey::encrypt: Encryption failed.")
+        } else {
+            Err(Error::sys()).context("In SuperKey::encrypt: Key is not an AES key.")
         }
     }
 }
@@ -386,7 +392,15 @@
         })
     }
 
-    pub fn get_per_boot_key_by_user_id(&self, user_id: UserId) -> Option<Arc<SuperKey>> {
+    pub fn get_per_boot_key_by_user_id(
+        &self,
+        user_id: UserId,
+    ) -> Option<Arc<dyn AesGcm + Send + Sync>> {
+        self.get_per_boot_key_by_user_id_internal(user_id)
+            .map(|sk| -> Arc<dyn AesGcm + Send + Sync> { sk })
+    }
+
+    fn get_per_boot_key_by_user_id_internal(&self, user_id: UserId) -> Option<Arc<SuperKey>> {
         self.data.user_keys.get(&user_id).and_then(|e| e.per_boot.as_ref().cloned())
     }
 
@@ -464,7 +478,7 @@
         match key.algorithm {
             SuperEncryptionAlgorithm::Aes256Gcm => match (metadata.iv(), metadata.aead_tag()) {
                 (Some(iv), Some(tag)) => key
-                    .aes_gcm_decrypt(blob, iv, tag)
+                    .decrypt(blob, iv, tag)
                     .context("In unwrap_key_with_key: Failed to decrypt the key blob."),
                 (iv, tag) => Err(Error::Rc(ResponseCode::VALUE_CORRUPTED)).context(format!(
                     concat!(
@@ -1093,7 +1107,7 @@
         legacy_importer: &LegacyImporter,
         user_id: UserId,
     ) -> Result<UserState> {
-        match self.get_per_boot_key_by_user_id(user_id) {
+        match self.get_per_boot_key_by_user_id_internal(user_id) {
             Some(super_key) => Ok(UserState::LskfUnlocked(super_key)),
             None => {
                 // Check if a super key exists in the database or legacy database.
@@ -1127,7 +1141,7 @@
         user_id: UserId,
         password: Option<&Password>,
     ) -> Result<UserState> {
-        match self.get_per_boot_key_by_user_id(user_id) {
+        match self.get_per_boot_key_by_user_id_internal(user_id) {
             Some(_) if password.is_none() => {
                 // Transitioning to swiping, delete only the super key in database and cache,
                 // and super-encrypted keys in database (and in KM).
@@ -1162,7 +1176,7 @@
         user_id: UserId,
         password: &Password,
     ) -> Result<UserState> {
-        match self.get_per_boot_key_by_user_id(user_id) {
+        match self.get_per_boot_key_by_user_id_internal(user_id) {
             Some(super_key) => {
                 log::info!("In unlock_and_get_user_state. Trying to unlock when already unlocked.");
                 Ok(UserState::LskfUnlocked(super_key))
diff --git a/keystore2/src/utils.rs b/keystore2/src/utils.rs
index c924bef..a312c4b 100644
--- a/keystore2/src/utils.rs
+++ b/keystore2/src/utils.rs
@@ -15,7 +15,8 @@
 //! This module implements utility functions used by the Keystore 2.0 service
 //! implementation.
 
-use crate::error::{map_binder_status, Error, ErrorCode};
+use crate::error::{map_binder_status, map_km_error, Error, ErrorCode};
+use crate::key_parameter::KeyParameter;
 use crate::permission;
 use crate::permission::{KeyPerm, KeyPermSet, KeystorePerm};
 use crate::{
@@ -23,7 +24,8 @@
     globals::LEGACY_IMPORTER,
 };
 use android_hardware_security_keymint::aidl::android::hardware::security::keymint::{
-    KeyCharacteristics::KeyCharacteristics, Tag::Tag,
+    IKeyMintDevice::IKeyMintDevice, KeyCharacteristics::KeyCharacteristics,
+    KeyParameter::KeyParameter as KmKeyParameter, Tag::Tag,
 };
 use android_os_permissions_aidl::aidl::android::os::IPermissionController;
 use android_security_apc::aidl::android::security::apc::{
@@ -40,6 +42,8 @@
     APC_COMPAT_ERROR_IGNORED, APC_COMPAT_ERROR_OK, APC_COMPAT_ERROR_OPERATION_PENDING,
     APC_COMPAT_ERROR_SYSTEM_ERROR,
 };
+use keystore2_crypto::{aes_gcm_decrypt, aes_gcm_encrypt, ZVec};
+use std::iter::IntoIterator;
 
 /// This function uses its namesake in the permission module and in
 /// combination with with_calling_sid from the binder crate to check
@@ -135,18 +139,60 @@
 /// representation of the keystore service.
 pub fn key_characteristics_to_internal(
     key_characteristics: Vec<KeyCharacteristics>,
-) -> Vec<crate::key_parameter::KeyParameter> {
+) -> Vec<KeyParameter> {
     key_characteristics
         .into_iter()
         .flat_map(|aidl_key_char| {
             let sec_level = aidl_key_char.securityLevel;
-            aidl_key_char.authorizations.into_iter().map(move |aidl_kp| {
-                crate::key_parameter::KeyParameter::new(aidl_kp.into(), sec_level)
-            })
+            aidl_key_char
+                .authorizations
+                .into_iter()
+                .map(move |aidl_kp| KeyParameter::new(aidl_kp.into(), sec_level))
         })
         .collect()
 }
 
+/// This function can be used to upgrade key blobs on demand. The return value of
+/// `km_op` is inspected and if ErrorCode::KEY_REQUIRES_UPGRADE is encountered,
+/// an attempt is made to upgrade the key blob. On success `new_blob_handler` is called
+/// with the upgraded blob as argument. Then `km_op` is called a second time with the
+/// upgraded blob as argument. On success a tuple of the `km_op`s result and the
+/// optional upgraded blob is returned.
+pub fn upgrade_keyblob_if_required_with<T, KmOp, NewBlobHandler>(
+    km_dev: &dyn IKeyMintDevice,
+    key_blob: &[u8],
+    upgrade_params: &[KmKeyParameter],
+    km_op: KmOp,
+    new_blob_handler: NewBlobHandler,
+) -> Result<(T, Option<Vec<u8>>)>
+where
+    KmOp: Fn(&[u8]) -> Result<T, Error>,
+    NewBlobHandler: FnOnce(&[u8]) -> Result<()>,
+{
+    match km_op(key_blob) {
+        Err(Error::Km(ErrorCode::KEY_REQUIRES_UPGRADE)) => {
+            let upgraded_blob = {
+                let _wp = watchdog::watch_millis(
+                    "In utils::upgrade_keyblob_if_required_with: calling upgradeKey.",
+                    500,
+                );
+                map_km_error(km_dev.upgradeKey(key_blob, upgrade_params))
+            }
+            .context("In utils::upgrade_keyblob_if_required_with: Upgrade failed.")?;
+
+            new_blob_handler(&upgraded_blob)
+                .context("In utils::upgrade_keyblob_if_required_with: calling new_blob_handler.")?;
+
+            km_op(&upgraded_blob)
+                .map(|v| (v, Some(upgraded_blob)))
+                .context("In utils::upgrade_keyblob_if_required_with: Calling km_op after upgrade.")
+        }
+        r => r
+            .map(|v| (v, None))
+            .context("In utils::upgrade_keyblob_if_required_with: Calling km_op."),
+    }
+}
+
 /// Converts a set of key characteristics from the internal representation into a set of
 /// Authorizations as they are used to convey key characteristics to the clients of keystore.
 pub fn key_parameters_to_authorizations(
@@ -255,6 +301,36 @@
     }
 }
 
+/// Trait implemented by objects that can be used to decrypt cipher text using AES-GCM.
+pub trait AesGcm {
+    /// Deciphers `data` using the initialization vector `iv` and AEAD tag `tag`
+    /// and AES-GCM. The implementation provides the key material and selects
+    /// the implementation variant, e.g., AES128 or AES265.
+    fn decrypt(&self, data: &[u8], iv: &[u8], tag: &[u8]) -> Result<ZVec>;
+
+    /// Encrypts `data` and returns the ciphertext, the initialization vector `iv`
+    /// and AEAD tag `tag`. The implementation provides the key material and selects
+    /// the implementation variant, e.g., AES128 or AES265.
+    fn encrypt(&self, plaintext: &[u8]) -> Result<(Vec<u8>, Vec<u8>, Vec<u8>)>;
+}
+
+/// Marks an object as AES-GCM key.
+pub trait AesGcmKey {
+    /// Provides access to the raw key material.
+    fn key(&self) -> &[u8];
+}
+
+impl<T: AesGcmKey> AesGcm for T {
+    fn decrypt(&self, data: &[u8], iv: &[u8], tag: &[u8]) -> Result<ZVec> {
+        aes_gcm_decrypt(data, iv, tag, self.key())
+            .context("In AesGcm<T>::decrypt: Decryption failed")
+    }
+
+    fn encrypt(&self, plaintext: &[u8]) -> Result<(Vec<u8>, Vec<u8>, Vec<u8>)> {
+        aes_gcm_encrypt(plaintext, self.key()).context("In AesGcm<T>::encrypt: Encryption failed.")
+    }
+}
+
 /// This module provides empty/noop implementations of the watch dog utility functions.
 #[cfg(not(feature = "watchdog"))]
 pub mod watchdog {