patches/system/vold/0005-Revert-vold-Wrapped-key-support-for-FBE.patch

From ae3379f770f270fd06e606c22aef55494300efae Mon Sep 17 00:00:00 2001
From: Jackeagle <jackeagle102@gmail.com>
Date: Wed, 19 Dec 2018 17:02:02 +0100
Subject: [PATCH 5/8] Revert "vold: Wrapped key support for FBE"

This reverts commit 659c9ec24095a9a6925157c83f961840f5df807d.
---
 Ext4Crypt.cpp                | 164 +++--------------------------------
 Ext4Crypt.h                  |   4 -
 KeyStorage.cpp               |  42 ---------
 KeyStorage.h                 |  11 +--
 KeyUtil.cpp                  |  31 +------
 KeyUtil.h                    |   4 +-
 Keymaster.cpp                |  26 ------
 Keymaster.h                  |   3 -
 VoldNativeService.cpp        |   8 --
 VoldNativeService.h          |   2 -
 binder/android/os/IVold.aidl |   1 -
 11 files changed, 20 insertions(+), 276 deletions(-)

diff --git a/Ext4Crypt.cpp b/Ext4Crypt.cpp
index 56650fe..6b60796 100644
--- a/Ext4Crypt.cpp
+++ b/Ext4Crypt.cpp
@@ -16,7 +16,6 @@
 
 #include "Ext4Crypt.h"
 
-#include "Keymaster.h"
 #include "KeyStorage.h"
 #include "KeyUtil.h"
 #include "Utils.h"
@@ -63,8 +62,6 @@ using android::base::StringPrintf;
 using android::base::WriteStringToFile;
 using android::vold::kEmptyAuthentication;
 using android::vold::KeyBuffer;
-using android::vold::Keymaster;
-using android::hardware::keymaster::V4_0::KeyFormat;
 
 namespace {
 
@@ -199,46 +196,12 @@ static bool read_and_fixate_user_ce_key(userid_t user_id,
     return false;
 }
 
-static bool is_wrapped_key_supported_common(const std::string& mount_point) {
-    struct fstab_rec* rec = fs_mgr_get_entry_for_mount_point(fstab_default, mount_point);
-    char const* contents_mode = NULL;
-    char const* filenames_mode = NULL;
-
-    fs_mgr_get_file_encryption_modes(rec, &contents_mode, &filenames_mode);
-    if (!contents_mode || !filenames_mode) {
-        LOG(ERROR) << "Couldn't read file or contents mode, returning false";
-        return false;
-    }
-
-    if (strcmp(contents_mode, "ice_wrapped_key_supported") == 0)
-        return true;
-    else
-        return false;
-}
-
-bool is_wrapped_key_supported() {
-    return is_wrapped_key_supported_common(DATA_MNT_POINT);
-}
-
-bool is_wrapped_key_supported_external() {
-    return false;
-}
-
 static bool read_and_install_user_ce_key(userid_t user_id,
                                          const android::vold::KeyAuthentication& auth) {
     if (s_ce_key_raw_refs.count(user_id) != 0) return true;
     KeyBuffer ce_key;
     if (!read_and_fixate_user_ce_key(user_id, auth, &ce_key)) return false;
     std::string ce_raw_ref;
-
-    if (is_wrapped_key_supported()) {
-        KeyBuffer ephemeral_wrapped_key;
-        if (!getEphemeralWrappedKey(KeyFormat::RAW, ce_key, &ephemeral_wrapped_key)) {
-           LOG(ERROR) << "Failed to export ce key";
-           return false;
-        }
-        ce_key = std::move(ephemeral_wrapped_key);
-    }
     if (!android::vold::installKey(ce_key, &ce_raw_ref)) return false;
     s_ce_keys[user_id] = std::move(ce_key);
     s_ce_key_raw_refs[user_id] = ce_raw_ref;
@@ -269,15 +232,8 @@ static bool destroy_dir(const std::string& dir) {
 // it creates keys in a fixed location.
 static bool create_and_install_user_keys(userid_t user_id, bool create_ephemeral) {
     KeyBuffer de_key, ce_key;
-
-    if(is_wrapped_key_supported()) {
-        if (!generateWrappedKey(user_id, android::vold::KeyType::DE_USER, &de_key)) return false;
-        if (!generateWrappedKey(user_id, android::vold::KeyType::CE_USER, &ce_key)) return false;
-    } else {
-        if (!android::vold::randomKey(&de_key)) return false;
-        if (!android::vold::randomKey(&ce_key)) return false;
-    }
-
+    if (!android::vold::randomKey(&de_key)) return false;
+    if (!android::vold::randomKey(&ce_key)) return false;
     if (create_ephemeral) {
         // If the key should be created as ephemeral, don't store it.
         s_ephemeral_users.insert(user_id);
@@ -294,36 +250,13 @@ static bool create_and_install_user_keys(userid_t user_id, bool create_ephemeral
         if (!android::vold::storeKeyAtomically(get_de_key_path(user_id), user_key_temp,
                 kEmptyAuthentication, de_key)) return false;
     }
-
-    /* Install the DE keys */
     std::string de_raw_ref;
-    std::string ce_raw_ref;
-
-    if (is_wrapped_key_supported()) {
-        KeyBuffer ephemeral_wrapped_de_key;
-        KeyBuffer ephemeral_wrapped_ce_key;
-
-        /* Export and install the DE keys */
-        if (!getEphemeralWrappedKey(KeyFormat::RAW, de_key, &ephemeral_wrapped_de_key)) {
-           LOG(ERROR) << "Failed to export de_key";
-           return false;
-        }
-        /* Export and install the CE keys */
-        if (!getEphemeralWrappedKey(KeyFormat::RAW, ce_key, &ephemeral_wrapped_ce_key)) {
-           LOG(ERROR) << "Failed to export de_key";
-           return false;
-        }
-
-        de_key = std::move(ephemeral_wrapped_de_key);
-        ce_key = std::move(ephemeral_wrapped_ce_key);
-    }
     if (!android::vold::installKey(de_key, &de_raw_ref)) return false;
-    if (!android::vold::installKey(ce_key, &ce_raw_ref)) return false;
-    s_ce_keys[user_id] = std::move(ce_key);
-
     s_de_key_raw_refs[user_id] = de_raw_ref;
+    std::string ce_raw_ref;
+    if (!android::vold::installKey(ce_key, &ce_raw_ref)) return false;
+    s_ce_keys[user_id] = ce_key;
     s_ce_key_raw_refs[user_id] = ce_raw_ref;
-
     LOG(DEBUG) << "Created keys for user " << user_id;
     return true;
 }
@@ -388,14 +321,6 @@ static bool load_all_de_keys() {
             KeyBuffer key;
             if (!android::vold::retrieveKey(key_path, kEmptyAuthentication, &key)) return false;
             std::string raw_ref;
-            if (is_wrapped_key_supported()) {
-                KeyBuffer ephemeral_wrapped_key;
-                if (!getEphemeralWrappedKey(KeyFormat::RAW, key, &ephemeral_wrapped_key)) {
-                   LOG(ERROR) << "Failed to export de_key in create_and_install_user_keys";
-                   return false;
-                }
-                key = std::move(ephemeral_wrapped_key);
-            }
             if (!android::vold::installKey(key, &raw_ref)) return false;
             s_de_key_raw_refs[user_id] = raw_ref;
             LOG(DEBUG) << "Installed de key for user " << user_id;
@@ -408,7 +333,6 @@ static bool load_all_de_keys() {
 
 bool e4crypt_initialize_global_de() {
     LOG(INFO) << "e4crypt_initialize_global_de";
-    bool wrapped_key_supported = false;
 
     if (s_global_de_initialized) {
         LOG(INFO) << "Already initialized";
@@ -416,11 +340,8 @@ bool e4crypt_initialize_global_de() {
     }
 
     PolicyKeyRef device_ref;
-    wrapped_key_supported = is_wrapped_key_supported();
-
-    if (!android::vold::retrieveAndInstallKey(true, kEmptyAuthentication,
-                       device_key_path, device_key_temp,
-                           &device_ref.key_raw_ref, wrapped_key_supported))
+    if (!android::vold::retrieveAndInstallKey(true, kEmptyAuthentication, device_key_path,
+                                              device_key_temp, &device_ref.key_raw_ref))
         return false;
     get_data_file_encryption_modes(&device_ref);
 
@@ -594,7 +515,6 @@ static bool read_or_create_volkey(const std::string& misc_path, const std::strin
                                   PolicyKeyRef* key_ref) {
     auto secdiscardable_path = volume_secdiscardable_path(volume_uuid);
     std::string secdiscardable_hash;
-    bool wrapped_key_supported = false;
     if (android::vold::pathExists(secdiscardable_path)) {
         if (!android::vold::readSecdiscardable(secdiscardable_path, &secdiscardable_hash))
             return false;
@@ -612,10 +532,8 @@ static bool read_or_create_volkey(const std::string& misc_path, const std::strin
         return false;
     }
     android::vold::KeyAuthentication auth("", secdiscardable_hash);
-    wrapped_key_supported = is_wrapped_key_supported_external();
-
     if (!android::vold::retrieveAndInstallKey(true, auth, key_path, key_path + "_tmp",
-                                              &key_ref->key_raw_ref, wrapped_key_supported))
+                                              &key_ref->key_raw_ref))
         return false;
     key_ref->contents_mode =
         android::base::GetProperty("ro.crypto.volume.contents_mode", "aes-256-xts");
@@ -641,74 +559,20 @@ bool e4crypt_add_user_key_auth(userid_t user_id, int serial, const std::string&
     if (!parse_hex(secret_hex, &secret)) return false;
     auto auth = secret.empty() ? kEmptyAuthentication
                                    : android::vold::KeyAuthentication(token, secret);
+    auto it = s_ce_keys.find(user_id);
+    if (it == s_ce_keys.end()) {
+        LOG(ERROR) << "Key not loaded into memory, can't change for user " << user_id;
+        return false;
+    }
+    const auto &ce_key = it->second;
     auto const directory_path = get_ce_key_directory_path(user_id);
     auto const paths = get_ce_key_paths(directory_path);
-
-    KeyBuffer ce_key;
-    if(is_wrapped_key_supported()) {
-        std::string ce_key_current_path = get_ce_key_current_path(directory_path);
-        if (android::vold::retrieveKey(ce_key_current_path, kEmptyAuthentication, &ce_key)) {
-            LOG(DEBUG) << "Successfully retrieved key";
-        } else {
-            if (android::vold::retrieveKey(ce_key_current_path, auth, &ce_key)) {
-                LOG(DEBUG) << "Successfully retrieved key";
-            }
-        }
-    } else {
-        auto it = s_ce_keys.find(user_id);
-        if (it == s_ce_keys.end()) {
-            LOG(ERROR) << "Key not loaded into memory, can't change for user " << user_id;
-            return false;
-        }
-        ce_key = it->second;
-    }
-
     std::string ce_key_path;
     if (!get_ce_key_new_path(directory_path, paths, &ce_key_path)) return false;
     if (!android::vold::storeKeyAtomically(ce_key_path, user_key_temp, auth, ce_key)) return false;
     return true;
 }
 
-bool e4crypt_clear_user_key_auth(userid_t user_id, int serial, const std::string& token_hex,
-                                 const std::string& secret_hex) {
-    LOG(DEBUG) << "e4crypt_clear_user_key_auth " << user_id << " serial=" << serial
-               << " token_present=" << (token_hex != "!");
-    if (!e4crypt_is_native()) return true;
-    if (s_ephemeral_users.count(user_id) != 0) return true;
-    std::string token, secret;
-
-    if (!parse_hex(token_hex, &token)) return false;
-    if (!parse_hex(secret_hex, &secret)) return false;
-
-    if (is_wrapped_key_supported()) {
-        auto const directory_path = get_ce_key_directory_path(user_id);
-        auto const paths = get_ce_key_paths(directory_path);
-
-        KeyBuffer ce_key;
-        std::string ce_key_current_path = get_ce_key_current_path(directory_path);
-
-        auto auth = android::vold::KeyAuthentication(token, secret);
-        /* Retrieve key while removing a pin. A secret is needed */
-        if (android::vold::retrieveKey(ce_key_current_path, auth, &ce_key)) {
-            LOG(DEBUG) << "Successfully retrieved key";
-        } else {
-            /* Retrieve key when going None to swipe and vice versa when a
-               synthetic password is present */
-            if (android::vold::retrieveKey(ce_key_current_path, kEmptyAuthentication, &ce_key)) {
-                LOG(DEBUG) << "Successfully retrieved key";
-            }
-        }
-
-        std::string ce_key_path;
-        if (!get_ce_key_new_path(directory_path, paths, &ce_key_path)) return false;
-        if (!android::vold::storeKeyAtomically(ce_key_path, user_key_temp, kEmptyAuthentication, ce_key))
-            return false;
-    } else {
-        if(!e4crypt_add_user_key_auth(user_id, serial, "!", "!")) return false;
-    }
-    return true;
-}
-
 bool e4crypt_fixate_newest_user_key_auth(userid_t user_id) {
     LOG(DEBUG) << "e4crypt_fixate_newest_user_key_auth " << user_id;
     if (!e4crypt_is_native()) return true;
diff --git a/Ext4Crypt.h b/Ext4Crypt.h
index 5101bf6..a43a68a 100644
--- a/Ext4Crypt.h
+++ b/Ext4Crypt.h
@@ -25,8 +25,6 @@ bool e4crypt_vold_create_user_key(userid_t user_id, int serial, bool ephemeral);
 bool e4crypt_destroy_user_key(userid_t user_id);
 bool e4crypt_add_user_key_auth(userid_t user_id, int serial, const std::string& token,
                                const std::string& secret);
-bool e4crypt_clear_user_key_auth(userid_t user_id, int serial, const std::string& token_hex,
-                               const std::string& secret_hex);
 bool e4crypt_fixate_newest_user_key_auth(userid_t user_id);
 
 bool e4crypt_unlock_user_key(userid_t user_id, int serial, const std::string& token,
@@ -38,5 +36,3 @@ bool e4crypt_prepare_user_storage(const std::string& volume_uuid, userid_t user_
 bool e4crypt_destroy_user_storage(const std::string& volume_uuid, userid_t user_id, int flags);
 
 bool e4crypt_destroy_volume_keys(const std::string& volume_uuid);
-bool is_wrapped_key_supported();
-bool is_wrapped_key_supported_external();
diff --git a/KeyStorage.cpp b/KeyStorage.cpp
index 69cd41c..0518930 100644
--- a/KeyStorage.cpp
+++ b/KeyStorage.cpp
@@ -61,7 +61,6 @@ static constexpr size_t SECDISCARDABLE_BYTES = 1 << 14;
 static constexpr size_t STRETCHED_BYTES = 1 << 6;
 
 static constexpr uint32_t AUTH_TIMEOUT = 30;  // Seconds
-constexpr int EXT4_AES_256_XTS_KEY_SIZE = 64;
 
 static const char* kCurrentVersion = "1";
 static const char* kRmPath = "/system/bin/rm";
@@ -127,47 +126,6 @@ static bool generateKeymasterKey(Keymaster& keymaster, const KeyAuthentication&
     return keymaster.generateKey(paramBuilder, key);
 }
 
-bool generateWrappedKey(userid_t user_id, KeyType key_type,
-                                     KeyBuffer* key) {
-    Keymaster keymaster;
-    if (!keymaster) return false;
-    *key = KeyBuffer(EXT4_AES_256_XTS_KEY_SIZE);
-    std::string key_temp;
-    auto paramBuilder = km::AuthorizationSetBuilder()
-                               .AesEncryptionKey(AES_KEY_BYTES * 8)
-                               .GcmModeMinMacLen(GCM_MAC_BYTES * 8)
-                               .Authorization(km::TAG_USER_ID, user_id);
-    km::KeyParameter param1;
-    param1.tag = (km::Tag) (android::hardware::keymaster::V4_0::KM_TAG_FBE_ICE);
-    param1.f.boolValue = true;
-    paramBuilder.push_back(param1);
-
-    km::KeyParameter param2;
-    if ((key_type == KeyType::DE_USER) || (key_type == KeyType::DE_SYS)) {
-        param2.tag = (km::Tag) (android::hardware::keymaster::V4_0::KM_TAG_KEY_TYPE);
-        param2.f.integer = 0;
-    } else if (key_type == KeyType::CE_USER) {
-        param2.tag = (km::Tag) (android::hardware::keymaster::V4_0::KM_TAG_KEY_TYPE);
-        param2.f.integer = 1;
-    }
-    paramBuilder.push_back(param2);
-
-    if (!keymaster.generateKey(paramBuilder, &key_temp)) return false;
-    *key = KeyBuffer(key_temp.size());
-    memcpy(reinterpret_cast<void*>(key->data()), key_temp.c_str(), key->size());
-    return true;
-}
-
-bool getEphemeralWrappedKey(km::KeyFormat format, KeyBuffer& kmKey, KeyBuffer* key) {
-    std::string key_temp;
-    Keymaster keymaster;
-    if (!keymaster) return false;
-    if (!keymaster.exportKey(format, kmKey, "!", "!", &key_temp)) return false;
-    *key = KeyBuffer(key_temp.size());
-    memcpy(reinterpret_cast<void*>(key->data()), key_temp.c_str(), key->size());
-    return true;
-}
-
 static std::pair<km::AuthorizationSet, km::HardwareAuthToken> beginParams(
     const KeyAuthentication& auth, const std::string& appId) {
     auto paramBuilder = km::AuthorizationSetBuilder()
diff --git a/KeyStorage.h b/KeyStorage.h
index 0c2609e..786e5b4 100644
--- a/KeyStorage.h
+++ b/KeyStorage.h
@@ -17,9 +17,8 @@
 #ifndef ANDROID_VOLD_KEYSTORAGE_H
 #define ANDROID_VOLD_KEYSTORAGE_H
 
-#include "Keymaster.h"
 #include "KeyBuffer.h"
-#include <ext4_utils/ext4_crypt.h>
+
 #include <string>
 
 namespace android {
@@ -40,12 +39,6 @@ class KeyAuthentication {
     const std::string secret;
 };
 
-enum class KeyType {
-    DE_SYS,
-    DE_USER,
-    CE_USER
-};
-
 extern const KeyAuthentication kEmptyAuthentication;
 
 // Checks if path "path" exists.
@@ -74,8 +67,6 @@ bool retrieveKey(const std::string& dir, const KeyAuthentication& auth, KeyBuffe
 bool destroyKey(const std::string& dir);
 
 bool runSecdiscardSingle(const std::string& file);
-bool generateWrappedKey(userid_t user_id, KeyType key_type, KeyBuffer* key);
-bool getEphemeralWrappedKey(km::KeyFormat format, KeyBuffer& kmKey, KeyBuffer* key);
 }  // namespace vold
 }  // namespace android
 
diff --git a/KeyUtil.cpp b/KeyUtil.cpp
index e8c366f..9885440 100644
--- a/KeyUtil.cpp
+++ b/KeyUtil.cpp
@@ -27,13 +27,8 @@
 #include <keyutils.h>
 
 #include "KeyStorage.h"
-#include "Ext4Crypt.h"
 #include "Utils.h"
 
-#define MAX_USER_ID 0xFFFFFFFF
-
-using android::hardware::keymaster::V4_0::KeyFormat;
-using android::vold::KeyType;
 namespace android {
 namespace vold {
 
@@ -127,14 +122,7 @@ bool installKey(const KeyBuffer& key, std::string* raw_ref) {
     ext4_encryption_key &ext4_key = *reinterpret_cast<ext4_encryption_key*>(ext4KeyBuffer.data());
 
     if (!fillKey(key, &ext4_key)) return false;
-    if (is_wrapped_key_supported()) {
-        /* When wrapped key is supported, only the first 32 bytes are
-           the same per boot. The second 32 bytes can change as the ephemeral
-           key is different. */
-        *raw_ref = generateKeyRef(ext4_key.raw, (ext4_key.size)/2);
-    } else {
-        *raw_ref = generateKeyRef(ext4_key.raw, ext4_key.size);
-    }
+    *raw_ref = generateKeyRef(ext4_key.raw, ext4_key.size);
     key_serial_t device_keyring;
     if (!e4cryptKeyring(&device_keyring)) return false;
     for (char const* const* name_prefix = NAME_PREFIXES; *name_prefix != nullptr; name_prefix++) {
@@ -175,7 +163,7 @@ bool evictKey(const std::string& raw_ref) {
 
 bool retrieveAndInstallKey(bool create_if_absent, const KeyAuthentication& key_authentication,
                            const std::string& key_path, const std::string& tmp_path,
-                           std::string* key_ref, bool wrapped_key_supported) {
+                           std::string* key_ref) {
     KeyBuffer key;
     if (pathExists(key_path)) {
         LOG(DEBUG) << "Key exists, using: " << key_path;
@@ -186,23 +174,10 @@ bool retrieveAndInstallKey(bool create_if_absent, const KeyAuthentication& key_a
            return false;
         }
         LOG(INFO) << "Creating new key in " << key_path;
-        if (wrapped_key_supported) {
-            if(!generateWrappedKey(MAX_USER_ID, KeyType::DE_SYS, &key)) return false;
-        } else {
-            if (!randomKey(&key)) return false;
-        }
+        if (!randomKey(&key)) return false;
         if (!storeKeyAtomically(key_path, tmp_path, key_authentication, key)) return false;
     }
 
-    if (wrapped_key_supported) {
-        KeyBuffer ephemeral_wrapped_key;
-        if (!getEphemeralWrappedKey(KeyFormat::RAW, key, &ephemeral_wrapped_key)) {
-            LOG(ERROR) << "Failed to export key in retrieveAndInstallKey";
-            return false;
-        }
-        key = std::move(ephemeral_wrapped_key);
-    }
-
     if (!installKey(key, key_ref)) {
         LOG(ERROR) << "Failed to install key in " << key_path;
         return false;
diff --git a/KeyUtil.h b/KeyUtil.h
index e73c065..a85eca1 100644
--- a/KeyUtil.h
+++ b/KeyUtil.h
@@ -19,7 +19,6 @@
 
 #include "KeyBuffer.h"
 #include "KeyStorage.h"
-#include "Keymaster.h"
 
 #include <string>
 #include <memory>
@@ -32,9 +31,10 @@ bool installKey(const KeyBuffer& key, std::string* raw_ref);
 bool evictKey(const std::string& raw_ref);
 bool retrieveAndInstallKey(bool create_if_absent, const KeyAuthentication& key_authentication,
                            const std::string& key_path, const std::string& tmp_path,
-                           std::string* key_ref, bool wrapped_key_supported);
+                           std::string* key_ref);
 bool retrieveKey(bool create_if_absent, const std::string& key_path,
                  const std::string& tmp_path, KeyBuffer* key);
+
 }  // namespace vold
 }  // namespace android
 
diff --git a/Keymaster.cpp b/Keymaster.cpp
index ab39ef8..aad4387 100644
--- a/Keymaster.cpp
+++ b/Keymaster.cpp
@@ -138,32 +138,6 @@ bool Keymaster::generateKey(const km::AuthorizationSet& inParams, std::string* k
     return true;
 }
 
-bool Keymaster::exportKey(km::KeyFormat format, KeyBuffer& kmKey, const std::string& clientId,
-                          const std::string& appData, std::string* key) {
-    auto kmKeyBlob = km::support::blob2hidlVec(std::string(kmKey.data(), kmKey.size()));
-    auto emptyAssign = NULL;
-    auto kmClientId = (clientId == "!") ? emptyAssign: km::support::blob2hidlVec(clientId);
-    auto kmAppData = (appData == "!") ? emptyAssign: km::support::blob2hidlVec(appData);
-    km::ErrorCode km_error;
-    auto hidlCb = [&](km::ErrorCode ret, const hidl_vec<uint8_t>& exportedKeyBlob) {
-        km_error = ret;
-        if (km_error != km::ErrorCode::OK) return;
-        if(key)
-            key->assign(reinterpret_cast<const char*>(&exportedKeyBlob[0]),
-                            exportedKeyBlob.size());
-    };
-    auto error = mDevice->exportKey(format, kmKeyBlob, kmClientId, kmAppData, hidlCb);
-    if (!error.isOk()) {
-        LOG(ERROR) << "export_key failed: " << error.description();
-        return false;
-    }
-    if (km_error != km::ErrorCode::OK) {
-        LOG(ERROR) << "export_key failed, code " << int32_t(km_error);
-        return false;
-    }
-    return true;
-}
-
 bool Keymaster::deleteKey(const std::string& key) {
     auto keyBlob = km::support::blob2hidlVec(key);
     auto error = mDevice->deleteKey(keyBlob);
diff --git a/Keymaster.h b/Keymaster.h
index c0ec4d3..fabe0f4 100644
--- a/Keymaster.h
+++ b/Keymaster.h
@@ -102,9 +102,6 @@ class Keymaster {
     explicit operator bool() { return mDevice.get() != nullptr; }
     // Generate a key in the keymaster from the given params.
     bool generateKey(const km::AuthorizationSet& inParams, std::string* key);
-    // Export a key from keymaster.
-    bool exportKey(km::KeyFormat format, KeyBuffer& kmKey, const std::string& clientId,
-                   const std::string& appData, std::string* key);
     // If the keymaster supports it, permanently delete a key.
     bool deleteKey(const std::string& key);
     // Replace stored key blob in response to KM_ERROR_KEY_REQUIRES_UPGRADE.
diff --git a/VoldNativeService.cpp b/VoldNativeService.cpp
index 6bd506a..6d6c6ec 100644
--- a/VoldNativeService.cpp
+++ b/VoldNativeService.cpp
@@ -715,14 +715,6 @@ binder::Status VoldNativeService::addUserKeyAuth(int32_t userId, int32_t userSer
     return translateBool(e4crypt_add_user_key_auth(userId, userSerial, token, secret));
 }
 
-binder::Status VoldNativeService::clearUserKeyAuth(int32_t userId, int32_t userSerial,
-        const std::string& token, const std::string& secret) {
-    ENFORCE_UID(AID_SYSTEM);
-    ACQUIRE_CRYPT_LOCK;
-
-    return translateBool(e4crypt_clear_user_key_auth(userId, userSerial, token, secret));
-}
-
 binder::Status VoldNativeService::fixateNewestUserKeyAuth(int32_t userId) {
     ENFORCE_UID(AID_SYSTEM);
     ACQUIRE_CRYPT_LOCK;
diff --git a/VoldNativeService.h b/VoldNativeService.h
index 2403678..da8c660 100644
--- a/VoldNativeService.h
+++ b/VoldNativeService.h
@@ -103,8 +103,6 @@ public:
 
     binder::Status addUserKeyAuth(int32_t userId, int32_t userSerial,
             const std::string& token, const std::string& secret);
-    binder::Status clearUserKeyAuth(int32_t userId, int32_t userSerial,
-            const std::string& token, const std::string& secret);
     binder::Status fixateNewestUserKeyAuth(int32_t userId);
 
     binder::Status unlockUserKey(int32_t userId, int32_t userSerial,
diff --git a/binder/android/os/IVold.aidl b/binder/android/os/IVold.aidl
index 3a54390..9f5b21a 100644
--- a/binder/android/os/IVold.aidl
+++ b/binder/android/os/IVold.aidl
@@ -85,7 +85,6 @@ interface IVold {
     void destroyUserKey(int userId);
 
     void addUserKeyAuth(int userId, int userSerial, @utf8InCpp String token, @utf8InCpp String secret);
-    void clearUserKeyAuth(int userId, int userSerial, @utf8InCpp String token, @utf8InCpp String secret);
     void fixateNewestUserKeyAuth(int userId);
 
     void unlockUserKey(int userId, int userSerial, @utf8InCpp String token, @utf8InCpp String secret);
-- 
2.21.0