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gerrit.omnirom.org / android_system_security / refs/heads/android-15 / . / keystore2 / src / database.rs
blob: 9f27b5a3769eef4e081a6ae9424c62726587fb9f [file] [log] [blame] [edit]
// Copyright 2020, The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//! This is the Keystore 2.0 database module.
//! The database module provides a connection to the backing SQLite store.
//! We have two databases one for persistent key blob storage and one for
//! items that have a per boot life cycle.
//!
//! ## Persistent database
//! The persistent database has tables for key blobs. They are organized
//! as follows:
//! The `keyentry` table is the primary table for key entries. It is
//! accompanied by two tables for blobs and parameters.
//! Each key entry occupies exactly one row in the `keyentry` table and
//! zero or more rows in the tables `blobentry` and `keyparameter`.
//!
//! ## Per boot database
//! The per boot database stores items with a per boot lifecycle.
//! Currently, there is only the `grant` table in this database.
//! Grants are references to a key that can be used to access a key by
//! clients that don't own that key. Grants can only be created by the
//! owner of a key. And only certain components can create grants.
//! This is governed by SEPolicy.
//!
//! ## Access control
//! Some database functions that load keys or create grants perform
//! access control. This is because in some cases access control
//! can only be performed after some information about the designated
//! key was loaded from the database. To decouple the permission checks
//! from the database module these functions take permission check
//! callbacks.
mod perboot;
pub(crate) mod utils;
mod versioning;
#[cfg(test)]
pub mod tests;
use crate::gc::Gc;
use crate::impl_metadata; // This is in database/utils.rs
use crate::key_parameter::{KeyParameter, KeyParameterValue, Tag};
use crate::ks_err;
use crate::permission::KeyPermSet;
use crate::utils::{get_current_time_in_milliseconds, watchdog as wd, AID_USER_OFFSET};
use crate::{
error::{Error as KsError, ErrorCode, ResponseCode},
super_key::SuperKeyType,
};
use android_hardware_security_keymint::aidl::android::hardware::security::keymint::{
HardwareAuthToken::HardwareAuthToken, HardwareAuthenticatorType::HardwareAuthenticatorType,
SecurityLevel::SecurityLevel,
};
use android_security_metrics::aidl::android::security::metrics::{
Storage::Storage as MetricsStorage, StorageStats::StorageStats,
};
use android_system_keystore2::aidl::android::system::keystore2::{
Domain::Domain, KeyDescriptor::KeyDescriptor,
};
use anyhow::{anyhow, Context, Result};
use keystore2_flags;
use std::{convert::TryFrom, convert::TryInto, ops::Deref, sync::LazyLock, time::SystemTimeError};
use utils as db_utils;
use utils::SqlField;
use keystore2_crypto::ZVec;
use log::error;
#[cfg(not(test))]
use rand::prelude::random;
use rusqlite::{
params, params_from_iter,
types::FromSql,
types::FromSqlResult,
types::ToSqlOutput,
types::{FromSqlError, Value, ValueRef},
Connection, OptionalExtension, ToSql, Transaction,
};
use std::{
collections::{HashMap, HashSet},
path::Path,
sync::{Arc, Condvar, Mutex},
time::{Duration, SystemTime},
};
use TransactionBehavior::Immediate;
#[cfg(test)]
use tests::random;
/// Wrapper for `rusqlite::TransactionBehavior` which includes information about the transaction
/// being performed.
#[derive(Clone, Copy)]
enum TransactionBehavior {
Deferred,
Immediate(&'static str),
}
impl From<TransactionBehavior> for rusqlite::TransactionBehavior {
fn from(val: TransactionBehavior) -> Self {
match val {
TransactionBehavior::Deferred => rusqlite::TransactionBehavior::Deferred,
TransactionBehavior::Immediate(_) => rusqlite::TransactionBehavior::Immediate,
}
}
}
impl TransactionBehavior {
fn name(&self) -> Option<&'static str> {
match self {
TransactionBehavior::Deferred => None,
TransactionBehavior::Immediate(v) => Some(v),
}
}
}
/// Access information for a key.
#[derive(Debug)]
struct KeyAccessInfo {
key_id: i64,
descriptor: KeyDescriptor,
vector: Option<KeyPermSet>,
}
/// If the database returns a busy error code, retry after this interval.
const DB_BUSY_RETRY_INTERVAL: Duration = Duration::from_micros(500);
impl_metadata!(
/// A set of metadata for key entries.
#[derive(Debug, Default, Eq, PartialEq)]
pub struct KeyMetaData;
/// A metadata entry for key entries.
#[derive(Debug, Eq, PartialEq, Ord, PartialOrd)]
pub enum KeyMetaEntry {
/// Date of the creation of the key entry.
CreationDate(DateTime) with accessor creation_date,
/// Expiration date for attestation keys.
AttestationExpirationDate(DateTime) with accessor attestation_expiration_date,
/// CBOR Blob that represents a COSE_Key and associated metadata needed for remote
/// provisioning
AttestationMacedPublicKey(Vec<u8>) with accessor attestation_maced_public_key,
/// Vector representing the raw public key so results from the server can be matched
/// to the right entry
AttestationRawPubKey(Vec<u8>) with accessor attestation_raw_pub_key,
/// SEC1 public key for ECDH encryption
Sec1PublicKey(Vec<u8>) with accessor sec1_public_key,
// --- ADD NEW META DATA FIELDS HERE ---
// For backwards compatibility add new entries only to
// end of this list and above this comment.
};
);
impl KeyMetaData {
fn load_from_db(key_id: i64, tx: &Transaction) -> Result<Self> {
let mut stmt = tx
.prepare(
"SELECT tag, data from persistent.keymetadata
WHERE keyentryid = ?;",
)
.context(ks_err!("KeyMetaData::load_from_db: prepare statement failed."))?;
let mut metadata: HashMap<i64, KeyMetaEntry> = Default::default();
let mut rows = stmt
.query(params![key_id])
.context(ks_err!("KeyMetaData::load_from_db: query failed."))?;
db_utils::with_rows_extract_all(&mut rows, |row| {
let db_tag: i64 = row.get(0).context("Failed to read tag.")?;
metadata.insert(
db_tag,
KeyMetaEntry::new_from_sql(db_tag, &SqlField::new(1, row))
.context("Failed to read KeyMetaEntry.")?,
);
Ok(())
})
.context(ks_err!("KeyMetaData::load_from_db."))?;
Ok(Self { data: metadata })
}
fn store_in_db(&self, key_id: i64, tx: &Transaction) -> Result<()> {
let mut stmt = tx
.prepare(
"INSERT or REPLACE INTO persistent.keymetadata (keyentryid, tag, data)
VALUES (?, ?, ?);",
)
.context(ks_err!("KeyMetaData::store_in_db: Failed to prepare statement."))?;
let iter = self.data.iter();
for (tag, entry) in iter {
stmt.insert(params![key_id, tag, entry,]).with_context(|| {
ks_err!("KeyMetaData::store_in_db: Failed to insert {:?}", entry)
})?;
}
Ok(())
}
}
impl_metadata!(
/// A set of metadata for key blobs.
#[derive(Debug, Default, Eq, PartialEq)]
pub struct BlobMetaData;
/// A metadata entry for key blobs.
#[derive(Debug, Eq, PartialEq, Ord, PartialOrd)]
pub enum BlobMetaEntry {
/// If present, indicates that the blob is encrypted with another key or a key derived
/// from a password.
EncryptedBy(EncryptedBy) with accessor encrypted_by,
/// If the blob is password encrypted this field is set to the
/// salt used for the key derivation.
Salt(Vec<u8>) with accessor salt,
/// If the blob is encrypted, this field is set to the initialization vector.
Iv(Vec<u8>) with accessor iv,
/// If the blob is encrypted, this field holds the AEAD TAG.
AeadTag(Vec<u8>) with accessor aead_tag,
/// The uuid of the owning KeyMint instance.
KmUuid(Uuid) with accessor km_uuid,
/// If the key is ECDH encrypted, this is the ephemeral public key
PublicKey(Vec<u8>) with accessor public_key,
/// If the key is encrypted with a MaxBootLevel key, this is the boot level
/// of that key
MaxBootLevel(i32) with accessor max_boot_level,
// --- ADD NEW META DATA FIELDS HERE ---
// For backwards compatibility add new entries only to
// end of this list and above this comment.
};
);
impl BlobMetaData {
fn load_from_db(blob_id: i64, tx: &Transaction) -> Result<Self> {
let mut stmt = tx
.prepare(
"SELECT tag, data from persistent.blobmetadata
WHERE blobentryid = ?;",
)
.context(ks_err!("BlobMetaData::load_from_db: prepare statement failed."))?;
let mut metadata: HashMap<i64, BlobMetaEntry> = Default::default();
let mut rows = stmt.query(params![blob_id]).context(ks_err!("query failed."))?;
db_utils::with_rows_extract_all(&mut rows, |row| {
let db_tag: i64 = row.get(0).context("Failed to read tag.")?;
metadata.insert(
db_tag,
BlobMetaEntry::new_from_sql(db_tag, &SqlField::new(1, row))
.context("Failed to read BlobMetaEntry.")?,
);
Ok(())
})
.context(ks_err!("BlobMetaData::load_from_db"))?;
Ok(Self { data: metadata })
}
fn store_in_db(&self, blob_id: i64, tx: &Transaction) -> Result<()> {
let mut stmt = tx
.prepare(
"INSERT or REPLACE INTO persistent.blobmetadata (blobentryid, tag, data)
VALUES (?, ?, ?);",
)
.context(ks_err!("BlobMetaData::store_in_db: Failed to prepare statement.",))?;
let iter = self.data.iter();
for (tag, entry) in iter {
stmt.insert(params![blob_id, tag, entry,]).with_context(|| {
ks_err!("BlobMetaData::store_in_db: Failed to insert {:?}", entry)
})?;
}
Ok(())
}
}
/// Indicates the type of the keyentry.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd)]
pub enum KeyType {
/// This is a client key type. These keys are created or imported through the Keystore 2.0
/// AIDL interface android.system.keystore2.
Client,
/// This is a super key type. These keys are created by keystore itself and used to encrypt
/// other key blobs to provide LSKF binding.
Super,
}
impl ToSql for KeyType {
fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
Ok(ToSqlOutput::Owned(Value::Integer(match self {
KeyType::Client => 0,
KeyType::Super => 1,
})))
}
}
impl FromSql for KeyType {
fn column_result(value: ValueRef) -> FromSqlResult<Self> {
match i64::column_result(value)? {
0 => Ok(KeyType::Client),
1 => Ok(KeyType::Super),
v => Err(FromSqlError::OutOfRange(v)),
}
}
}
/// Uuid representation that can be stored in the database.
/// Right now it can only be initialized from SecurityLevel.
/// Once KeyMint provides a UUID type a corresponding From impl shall be added.
#[derive(Debug, Clone, Copy, Default, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct Uuid([u8; 16]);
impl Deref for Uuid {
type Target = [u8; 16];
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl From<SecurityLevel> for Uuid {
fn from(sec_level: SecurityLevel) -> Self {
Self((sec_level.0 as u128).to_be_bytes())
}
}
impl ToSql for Uuid {
fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
self.0.to_sql()
}
}
impl FromSql for Uuid {
fn column_result(value: ValueRef<'_>) -> FromSqlResult<Self> {
let blob = Vec::<u8>::column_result(value)?;
if blob.len() != 16 {
return Err(FromSqlError::OutOfRange(blob.len() as i64));
}
let mut arr = [0u8; 16];
arr.copy_from_slice(&blob);
Ok(Self(arr))
}
}
/// Key entries that are not associated with any KeyMint instance, such as pure certificate
/// entries are associated with this UUID.
pub static KEYSTORE_UUID: Uuid = Uuid([
0x41, 0xe3, 0xb9, 0xce, 0x27, 0x58, 0x4e, 0x91, 0xbc, 0xfd, 0xa5, 0x5d, 0x91, 0x85, 0xab, 0x11,
]);
/// Indicates how the sensitive part of this key blob is encrypted.
#[derive(Debug, Eq, PartialEq, Ord, PartialOrd)]
pub enum EncryptedBy {
/// The keyblob is encrypted by a user password.
/// In the database this variant is represented as NULL.
Password,
/// The keyblob is encrypted by another key with wrapped key id.
/// In the database this variant is represented as non NULL value
/// that is convertible to i64, typically NUMERIC.
KeyId(i64),
}
impl ToSql for EncryptedBy {
fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
match self {
Self::Password => Ok(ToSqlOutput::Owned(Value::Null)),
Self::KeyId(id) => id.to_sql(),
}
}
}
impl FromSql for EncryptedBy {
fn column_result(value: ValueRef) -> FromSqlResult<Self> {
match value {
ValueRef::Null => Ok(Self::Password),
_ => Ok(Self::KeyId(i64::column_result(value)?)),
}
}
}
/// A database representation of wall clock time. DateTime stores unix epoch time as
/// i64 in milliseconds.
#[derive(Debug, Copy, Clone, Default, Eq, PartialEq, Ord, PartialOrd)]
pub struct DateTime(i64);
/// Error type returned when creating DateTime or converting it from and to
/// SystemTime.
#[derive(thiserror::Error, Debug)]
pub enum DateTimeError {
/// This is returned when SystemTime and Duration computations fail.
#[error(transparent)]
SystemTimeError(#[from] SystemTimeError),
/// This is returned when type conversions fail.
#[error(transparent)]
TypeConversion(#[from] std::num::TryFromIntError),
/// This is returned when checked time arithmetic failed.
#[error("Time arithmetic failed.")]
TimeArithmetic,
}
impl DateTime {
/// Constructs a new DateTime object denoting the current time. This may fail during
/// conversion to unix epoch time and during conversion to the internal i64 representation.
pub fn now() -> Result<Self, DateTimeError> {
Ok(Self(SystemTime::now().duration_since(SystemTime::UNIX_EPOCH)?.as_millis().try_into()?))
}
/// Constructs a new DateTime object from milliseconds.
pub fn from_millis_epoch(millis: i64) -> Self {
Self(millis)
}
/// Returns unix epoch time in milliseconds.
pub fn to_millis_epoch(self) -> i64 {
self.0
}
}
impl ToSql for DateTime {
fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
Ok(ToSqlOutput::Owned(Value::Integer(self.0)))
}
}
impl FromSql for DateTime {
fn column_result(value: ValueRef) -> FromSqlResult<Self> {
Ok(Self(i64::column_result(value)?))
}
}
impl TryInto<SystemTime> for DateTime {
type Error = DateTimeError;
fn try_into(self) -> Result<SystemTime, Self::Error> {
// We want to construct a SystemTime representation equivalent to self, denoting
// a point in time THEN, but we cannot set the time directly. We can only construct
// a SystemTime denoting NOW, and we can get the duration between EPOCH and NOW,
// and between EPOCH and THEN. With this common reference we can construct the
// duration between NOW and THEN which we can add to our SystemTime representation
// of NOW to get a SystemTime representation of THEN.
// Durations can only be positive, thus the if statement below.
let now = SystemTime::now();
let now_epoch = now.duration_since(SystemTime::UNIX_EPOCH)?;
let then_epoch = Duration::from_millis(self.0.try_into()?);
Ok(if now_epoch > then_epoch {
// then = now - (now_epoch - then_epoch)
now_epoch
.checked_sub(then_epoch)
.and_then(|d| now.checked_sub(d))
.ok_or(DateTimeError::TimeArithmetic)?
} else {
// then = now + (then_epoch - now_epoch)
then_epoch
.checked_sub(now_epoch)
.and_then(|d| now.checked_add(d))
.ok_or(DateTimeError::TimeArithmetic)?
})
}
}
impl TryFrom<SystemTime> for DateTime {
type Error = DateTimeError;
fn try_from(t: SystemTime) -> Result<Self, Self::Error> {
Ok(Self(t.duration_since(SystemTime::UNIX_EPOCH)?.as_millis().try_into()?))
}
}
#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Copy, Clone)]
enum KeyLifeCycle {
/// Existing keys have a key ID but are not fully populated yet.
/// This is a transient state. If Keystore finds any such keys when it starts up, it must move
/// them to Unreferenced for garbage collection.
Existing,
/// A live key is fully populated and usable by clients.
Live,
/// An unreferenced key is scheduled for garbage collection.
Unreferenced,
}
impl ToSql for KeyLifeCycle {
fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
match self {
Self::Existing => Ok(ToSqlOutput::Owned(Value::Integer(0))),
Self::Live => Ok(ToSqlOutput::Owned(Value::Integer(1))),
Self::Unreferenced => Ok(ToSqlOutput::Owned(Value::Integer(2))),
}
}
}
impl FromSql for KeyLifeCycle {
fn column_result(value: ValueRef) -> FromSqlResult<Self> {
match i64::column_result(value)? {
0 => Ok(KeyLifeCycle::Existing),
1 => Ok(KeyLifeCycle::Live),
2 => Ok(KeyLifeCycle::Unreferenced),
v => Err(FromSqlError::OutOfRange(v)),
}
}
}
/// Current state of a `blobentry` row.
#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Copy, Clone, Default)]
enum BlobState {
#[default]
/// Current blobentry (of its `subcomponent_type`) for the associated key.
Current,
/// Blobentry that is no longer the current blob (of its `subcomponent_type`) for the associated
/// key.
Superseded,
/// Blobentry for a key that no longer exists.
Orphaned,
}
impl ToSql for BlobState {
fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
match self {
Self::Current => Ok(ToSqlOutput::Owned(Value::Integer(0))),
Self::Superseded => Ok(ToSqlOutput::Owned(Value::Integer(1))),
Self::Orphaned => Ok(ToSqlOutput::Owned(Value::Integer(2))),
}
}
}
impl FromSql for BlobState {
fn column_result(value: ValueRef) -> FromSqlResult<Self> {
match i64::column_result(value)? {
0 => Ok(Self::Current),
1 => Ok(Self::Superseded),
2 => Ok(Self::Orphaned),
v => Err(FromSqlError::OutOfRange(v)),
}
}
}
/// Keys have a KeyMint blob component and optional public certificate and
/// certificate chain components.
/// KeyEntryLoadBits is a bitmap that indicates to `KeystoreDB::load_key_entry`
/// which components shall be loaded from the database if present.
#[derive(Debug, Clone, Copy, Eq, PartialEq, Ord, PartialOrd)]
pub struct KeyEntryLoadBits(u32);
impl KeyEntryLoadBits {
/// Indicate to `KeystoreDB::load_key_entry` that no component shall be loaded.
pub const NONE: KeyEntryLoadBits = Self(0);
/// Indicate to `KeystoreDB::load_key_entry` that the KeyMint component shall be loaded.
pub const KM: KeyEntryLoadBits = Self(1);
/// Indicate to `KeystoreDB::load_key_entry` that the Public components shall be loaded.
pub const PUBLIC: KeyEntryLoadBits = Self(2);
/// Indicate to `KeystoreDB::load_key_entry` that both components shall be loaded.
pub const BOTH: KeyEntryLoadBits = Self(3);
/// Returns true if this object indicates that the public components shall be loaded.
pub const fn load_public(&self) -> bool {
self.0 & Self::PUBLIC.0 != 0
}
/// Returns true if the object indicates that the KeyMint component shall be loaded.
pub const fn load_km(&self) -> bool {
self.0 & Self::KM.0 != 0
}
}
static KEY_ID_LOCK: LazyLock<KeyIdLockDb> = LazyLock::new(KeyIdLockDb::new);
struct KeyIdLockDb {
locked_keys: Mutex<HashSet<i64>>,
cond_var: Condvar,
}
/// A locked key. While a guard exists for a given key id, the same key cannot be loaded
/// from the database a second time. Most functions manipulating the key blob database
/// require a KeyIdGuard.
#[derive(Debug)]
pub struct KeyIdGuard(i64);
impl KeyIdLockDb {
fn new() -> Self {
Self { locked_keys: Mutex::new(HashSet::new()), cond_var: Condvar::new() }
}
/// This function blocks until an exclusive lock for the given key entry id can
/// be acquired. It returns a guard object, that represents the lifecycle of the
/// acquired lock.
fn get(&self, key_id: i64) -> KeyIdGuard {
let mut locked_keys = self.locked_keys.lock().unwrap();
while locked_keys.contains(&key_id) {
locked_keys = self.cond_var.wait(locked_keys).unwrap();
}
locked_keys.insert(key_id);
KeyIdGuard(key_id)
}
/// This function attempts to acquire an exclusive lock on a given key id. If the
/// given key id is already taken the function returns None immediately. If a lock
/// can be acquired this function returns a guard object, that represents the
/// lifecycle of the acquired lock.
fn try_get(&self, key_id: i64) -> Option<KeyIdGuard> {
let mut locked_keys = self.locked_keys.lock().unwrap();
if locked_keys.insert(key_id) {
Some(KeyIdGuard(key_id))
} else {
None
}
}
}
impl KeyIdGuard {
/// Get the numeric key id of the locked key.
pub fn id(&self) -> i64 {
self.0
}
}
impl Drop for KeyIdGuard {
fn drop(&mut self) {
let mut locked_keys = KEY_ID_LOCK.locked_keys.lock().unwrap();
locked_keys.remove(&self.0);
drop(locked_keys);
KEY_ID_LOCK.cond_var.notify_all();
}
}
/// This type represents a certificate and certificate chain entry for a key.
#[derive(Debug, Default)]
pub struct CertificateInfo {
cert: Option<Vec<u8>>,
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 {
Self { cert, cert_chain }
}
/// Take the cert
pub fn take_cert(&mut self) -> Option<Vec<u8>> {
self.cert.take()
}
/// Take the cert chain
pub fn take_cert_chain(&mut self) -> Option<Vec<u8>> {
self.cert_chain.take()
}
}
/// This type represents a certificate chain with a private key corresponding to the leaf
/// certificate. TODO(jbires): This will be used in a follow-on CL, for now it's used in the tests.
pub struct CertificateChain {
/// A KM key blob
pub private_key: ZVec,
/// A batch cert for private_key
pub batch_cert: Vec<u8>,
/// A full certificate chain from root signing authority to private_key, including batch_cert
/// for convenience.
pub cert_chain: Vec<u8>,
}
/// This type represents a Keystore 2.0 key entry.
/// An entry has a unique `id` by which it can be found in the database.
/// It has a security level field, key parameters, and three optional fields
/// for the KeyMint blob, public certificate and a public certificate chain.
#[derive(Debug, Default, Eq, PartialEq)]
pub struct KeyEntry {
id: i64,
key_blob_info: Option<(Vec<u8>, BlobMetaData)>,
cert: Option<Vec<u8>>,
cert_chain: Option<Vec<u8>>,
km_uuid: Uuid,
parameters: Vec<KeyParameter>,
metadata: KeyMetaData,
pure_cert: bool,
}
impl KeyEntry {
/// Returns the unique id of the Key entry.
pub fn id(&self) -> i64 {
self.id
}
/// Exposes the optional KeyMint blob.
pub fn key_blob_info(&self) -> &Option<(Vec<u8>, BlobMetaData)> {
&self.key_blob_info
}
/// Extracts the Optional KeyMint blob including its metadata.
pub fn take_key_blob_info(&mut self) -> Option<(Vec<u8>, BlobMetaData)> {
self.key_blob_info.take()
}
/// Exposes the optional public certificate.
pub fn cert(&self) -> &Option<Vec<u8>> {
&self.cert
}
/// Extracts the optional public certificate.
pub fn take_cert(&mut self) -> Option<Vec<u8>> {
self.cert.take()
}
/// Extracts the optional public certificate_chain.
pub fn take_cert_chain(&mut self) -> Option<Vec<u8>> {
self.cert_chain.take()
}
/// Returns the uuid of the owning KeyMint instance.
pub fn km_uuid(&self) -> &Uuid {
&self.km_uuid
}
/// Consumes this key entry and extracts the keyparameters from it.
pub fn into_key_parameters(self) -> Vec<KeyParameter> {
self.parameters
}
/// Exposes the key metadata of this key entry.
pub fn metadata(&self) -> &KeyMetaData {
&self.metadata
}
/// This returns true if the entry is a pure certificate entry with no
/// private key component.
pub fn pure_cert(&self) -> bool {
self.pure_cert
}
}
/// Indicates the sub component of a key entry for persistent storage.
#[derive(Debug, Clone, Copy, Eq, PartialEq, Ord, PartialOrd)]
pub struct SubComponentType(u32);
impl SubComponentType {
/// Persistent identifier for a key blob.
pub const KEY_BLOB: SubComponentType = Self(0);
/// Persistent identifier for a certificate blob.
pub const CERT: SubComponentType = Self(1);
/// Persistent identifier for a certificate chain blob.
pub const CERT_CHAIN: SubComponentType = Self(2);
}
impl ToSql for SubComponentType {
fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
self.0.to_sql()
}
}
impl FromSql for SubComponentType {
fn column_result(value: ValueRef) -> FromSqlResult<Self> {
Ok(Self(u32::column_result(value)?))
}
}
/// This trait is private to the database module. It is used to convey whether or not the garbage
/// collector shall be invoked after a database access. All closures passed to
/// `KeystoreDB::with_transaction` return a tuple (bool, T) where the bool indicates if the
/// gc needs to be triggered. This convenience function allows to turn any anyhow::Result<T>
/// into anyhow::Result<(bool, T)> by simply appending one of `.do_gc(bool)`, `.no_gc()`, or
/// `.need_gc()`.
trait DoGc<T> {
fn do_gc(self, need_gc: bool) -> Result<(bool, T)>;
fn no_gc(self) -> Result<(bool, T)>;
fn need_gc(self) -> Result<(bool, T)>;
}
impl<T> DoGc<T> for Result<T> {
fn do_gc(self, need_gc: bool) -> Result<(bool, T)> {
self.map(|r| (need_gc, r))
}
fn no_gc(self) -> Result<(bool, T)> {
self.do_gc(false)
}
fn need_gc(self) -> Result<(bool, T)> {
self.do_gc(true)
}
}
/// KeystoreDB wraps a connection to an SQLite database and tracks its
/// ownership. It also implements all of Keystore 2.0's database functionality.
pub struct KeystoreDB {
conn: Connection,
gc: Option<Arc<Gc>>,
perboot: Arc<perboot::PerbootDB>,
}
/// Database representation of the monotonic time retrieved from the system call clock_gettime with
/// CLOCK_BOOTTIME. Stores monotonic time as i64 in milliseconds.
#[derive(Debug, Copy, Clone, Default, Eq, PartialEq, Ord, PartialOrd)]
pub struct BootTime(i64);
impl BootTime {
/// Constructs a new BootTime
pub fn now() -> Self {
Self(get_current_time_in_milliseconds())
}
/// Returns the value of BootTime in milliseconds as i64
pub fn milliseconds(&self) -> i64 {
self.0
}
/// Returns the integer value of BootTime as i64
pub fn seconds(&self) -> i64 {
self.0 / 1000
}
/// Like i64::checked_sub.
pub fn checked_sub(&self, other: &Self) -> Option<Self> {
self.0.checked_sub(other.0).map(Self)
}
}
impl ToSql for BootTime {
fn to_sql(&self) -> rusqlite::Result<ToSqlOutput> {
Ok(ToSqlOutput::Owned(Value::Integer(self.0)))
}
}
impl FromSql for BootTime {
fn column_result(value: ValueRef) -> FromSqlResult<Self> {
Ok(Self(i64::column_result(value)?))
}
}
/// This struct encapsulates the information to be stored in the database about the auth tokens
/// received by keystore.
#[derive(Clone)]
pub struct AuthTokenEntry {
auth_token: HardwareAuthToken,
// Time received in milliseconds
time_received: BootTime,
}
impl AuthTokenEntry {
fn new(auth_token: HardwareAuthToken, time_received: BootTime) -> Self {
AuthTokenEntry { auth_token, time_received }
}
/// Checks if this auth token satisfies the given authentication information.
pub fn satisfies(&self, user_secure_ids: &[i64], auth_type: HardwareAuthenticatorType) -> bool {
user_secure_ids.iter().any(|&sid| {
(sid == self.auth_token.userId || sid == self.auth_token.authenticatorId)
&& ((auth_type.0 & self.auth_token.authenticatorType.0) != 0)
})
}
/// Returns the auth token wrapped by the AuthTokenEntry
pub fn auth_token(&self) -> &HardwareAuthToken {
&self.auth_token
}
/// Returns the auth token wrapped by the AuthTokenEntry
pub fn take_auth_token(self) -> HardwareAuthToken {
self.auth_token
}
/// Returns the time that this auth token was received.
pub fn time_received(&self) -> BootTime {
self.time_received
}
/// Returns the challenge value of the auth token.
pub fn challenge(&self) -> i64 {
self.auth_token.challenge
}
}
/// Information about a superseded blob (a blob that is no longer the
/// most recent blob of that type for a given key, due to upgrade or
/// replacement).
pub struct SupersededBlob {
/// ID
pub blob_id: i64,
/// Contents.
pub blob: Vec<u8>,
/// Metadata.
pub metadata: BlobMetaData,
}
impl KeystoreDB {
const UNASSIGNED_KEY_ID: i64 = -1i64;
const CURRENT_DB_VERSION: u32 = 2;
const UPGRADERS: &'static [fn(&Transaction) -> Result<u32>] =
&[Self::from_0_to_1, Self::from_1_to_2];
/// Name of the file that holds the cross-boot persistent database.
pub const PERSISTENT_DB_FILENAME: &'static str = "persistent.sqlite";
/// This will create a new database connection connecting the two
/// files persistent.sqlite and perboot.sqlite in the given directory.
/// It also attempts to initialize all of the tables.
/// KeystoreDB cannot be used by multiple threads.
/// Each thread should open their own connection using `thread_local!`.
pub fn new(db_root: &Path, gc: Option<Arc<Gc>>) -> Result<Self> {
let _wp = wd::watch("KeystoreDB::new");
let persistent_path = Self::make_persistent_path(db_root)?;
let conn = Self::make_connection(&persistent_path)?;
let mut db = Self { conn, gc, perboot: perboot::PERBOOT_DB.clone() };
db.with_transaction(Immediate("TX_new"), |tx| {
versioning::upgrade_database(tx, Self::CURRENT_DB_VERSION, Self::UPGRADERS)
.context(ks_err!("KeystoreDB::new: trying to upgrade database."))?;
Self::init_tables(tx).context("Trying to initialize tables.").no_gc()
})?;
Ok(db)
}
// This upgrade function deletes all MAX_BOOT_LEVEL keys, that were generated before
// cryptographic binding to the boot level keys was implemented.
fn from_0_to_1(tx: &Transaction) -> Result<u32> {
tx.execute(
"UPDATE persistent.keyentry SET state = ?
WHERE
id IN (SELECT keyentryid FROM persistent.keyparameter WHERE tag = ?)
AND
id NOT IN (
SELECT keyentryid FROM persistent.blobentry
WHERE id IN (
SELECT blobentryid FROM persistent.blobmetadata WHERE tag = ?
)
);",
params![KeyLifeCycle::Unreferenced, Tag::MAX_BOOT_LEVEL.0, BlobMetaData::MaxBootLevel],
)
.context(ks_err!("Failed to delete logical boot level keys."))?;
// DB version is now 1.
Ok(1)
}
// This upgrade function adds an additional `state INTEGER` column to the blobentry
// table, and populates it based on whether each blob is the most recent of its type for
// the corresponding key.
fn from_1_to_2(tx: &Transaction) -> Result<u32> {
tx.execute(
"ALTER TABLE persistent.blobentry ADD COLUMN state INTEGER DEFAULT 0;",
params![],
)
.context(ks_err!("Failed to add state column"))?;
// Mark keyblobs that are not the most recent for their corresponding key.
// This may take a while if there are excessive numbers of keys in the database.
let _wp = wd::watch("KeystoreDB::from_1_to_2 mark all non-current keyblobs");
let sc_key_blob = SubComponentType::KEY_BLOB;
let mut stmt = tx
.prepare(
"UPDATE persistent.blobentry SET state=?
WHERE subcomponent_type = ?
AND id NOT IN (
SELECT MAX(id) FROM persistent.blobentry
WHERE subcomponent_type = ?
GROUP BY keyentryid, subcomponent_type
);",
)
.context("Trying to prepare query to mark superseded keyblobs")?;
stmt.execute(params![BlobState::Superseded, sc_key_blob, sc_key_blob])
.context(ks_err!("Failed to set state=superseded state for keyblobs"))?;
log::info!("marked non-current blobentry rows for keyblobs as superseded");
// Mark keyblobs that don't have a corresponding key.
// This may take a while if there are excessive numbers of keys in the database.
let _wp = wd::watch("KeystoreDB::from_1_to_2 mark all orphaned keyblobs");
let mut stmt = tx
.prepare(
"UPDATE persistent.blobentry SET state=?
WHERE subcomponent_type = ?
AND NOT EXISTS (SELECT id FROM persistent.keyentry
WHERE id = keyentryid);",
)
.context("Trying to prepare query to mark orphaned keyblobs")?;
stmt.execute(params![BlobState::Orphaned, sc_key_blob])
.context(ks_err!("Failed to set state=orphaned for keyblobs"))?;
log::info!("marked orphaned blobentry rows for keyblobs");
// Add an index to make it fast to find out of date blobentry rows.
let _wp = wd::watch("KeystoreDB::from_1_to_2 add blobentry index");
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.blobentry_state_index
ON blobentry(subcomponent_type, state);",
[],
)
.context("Failed to create index blobentry_state_index.")?;
// Add an index to make it fast to find unreferenced keyentry rows.
let _wp = wd::watch("KeystoreDB::from_1_to_2 add keyentry state index");
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.keyentry_state_index
ON keyentry(state);",
[],
)
.context("Failed to create index keyentry_state_index.")?;
// DB version is now 2.
Ok(2)
}
fn init_tables(tx: &Transaction) -> Result<()> {
tx.execute(
"CREATE TABLE IF NOT EXISTS persistent.keyentry (
id INTEGER UNIQUE,
key_type INTEGER,
domain INTEGER,
namespace INTEGER,
alias BLOB,
state INTEGER,
km_uuid BLOB);",
[],
)
.context("Failed to initialize \"keyentry\" table.")?;
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.keyentry_id_index
ON keyentry(id);",
[],
)
.context("Failed to create index keyentry_id_index.")?;
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.keyentry_domain_namespace_index
ON keyentry(domain, namespace, alias);",
[],
)
.context("Failed to create index keyentry_domain_namespace_index.")?;
// Index added in v2 of database schema.
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.keyentry_state_index
ON keyentry(state);",
[],
)
.context("Failed to create index keyentry_state_index.")?;
tx.execute(
"CREATE TABLE IF NOT EXISTS persistent.blobentry (
id INTEGER PRIMARY KEY,
subcomponent_type INTEGER,
keyentryid INTEGER,
blob BLOB,
state INTEGER DEFAULT 0);", // `state` added in v2 of schema
[],
)
.context("Failed to initialize \"blobentry\" table.")?;
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.blobentry_keyentryid_index
ON blobentry(keyentryid);",
[],
)
.context("Failed to create index blobentry_keyentryid_index.")?;
// Index added in v2 of database schema.
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.blobentry_state_index
ON blobentry(subcomponent_type, state);",
[],
)
.context("Failed to create index blobentry_state_index.")?;
tx.execute(
"CREATE TABLE IF NOT EXISTS persistent.blobmetadata (
id INTEGER PRIMARY KEY,
blobentryid INTEGER,
tag INTEGER,
data ANY,
UNIQUE (blobentryid, tag));",
[],
)
.context("Failed to initialize \"blobmetadata\" table.")?;
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.blobmetadata_blobentryid_index
ON blobmetadata(blobentryid);",
[],
)
.context("Failed to create index blobmetadata_blobentryid_index.")?;
tx.execute(
"CREATE TABLE IF NOT EXISTS persistent.keyparameter (
keyentryid INTEGER,
tag INTEGER,
data ANY,
security_level INTEGER);",
[],
)
.context("Failed to initialize \"keyparameter\" table.")?;
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.keyparameter_keyentryid_index
ON keyparameter(keyentryid);",
[],
)
.context("Failed to create index keyparameter_keyentryid_index.")?;
tx.execute(
"CREATE TABLE IF NOT EXISTS persistent.keymetadata (
keyentryid INTEGER,
tag INTEGER,
data ANY,
UNIQUE (keyentryid, tag));",
[],
)
.context("Failed to initialize \"keymetadata\" table.")?;
tx.execute(
"CREATE INDEX IF NOT EXISTS persistent.keymetadata_keyentryid_index
ON keymetadata(keyentryid);",
[],
)
.context("Failed to create index keymetadata_keyentryid_index.")?;
tx.execute(
"CREATE TABLE IF NOT EXISTS persistent.grant (
id INTEGER UNIQUE,
grantee INTEGER,
keyentryid INTEGER,
access_vector INTEGER);",
[],
)
.context("Failed to initialize \"grant\" table.")?;
Ok(())
}
fn make_persistent_path(db_root: &Path) -> Result<String> {
// Build the path to the sqlite file.
let mut persistent_path = db_root.to_path_buf();
persistent_path.push(Self::PERSISTENT_DB_FILENAME);
// Now convert them to strings prefixed with "file:"
let mut persistent_path_str = "file:".to_owned();
persistent_path_str.push_str(&persistent_path.to_string_lossy());
// Connect to database in specific mode
let persistent_path_mode = if keystore2_flags::wal_db_journalmode_v3() {
"?journal_mode=WAL".to_owned()
} else {
"?journal_mode=DELETE".to_owned()
};
persistent_path_str.push_str(&persistent_path_mode);
Ok(persistent_path_str)
}
fn make_connection(persistent_file: &str) -> Result<Connection> {
let conn =
Connection::open_in_memory().context("Failed to initialize SQLite connection.")?;
loop {
if let Err(e) = conn
.execute("ATTACH DATABASE ? as persistent;", params![persistent_file])
.context("Failed to attach database persistent.")
{
if Self::is_locked_error(&e) {
std::thread::sleep(DB_BUSY_RETRY_INTERVAL);
continue;
} else {
return Err(e);
}
}
break;
}
// Drop the cache size from default (2M) to 0.5M
conn.execute("PRAGMA persistent.cache_size = -500;", params![])
.context("Failed to decrease cache size for persistent db")?;
Ok(conn)
}
fn do_table_size_query(
&mut self,
storage_type: MetricsStorage,
query: &str,
params: &[&str],
) -> Result<StorageStats> {
let (total, unused) = self.with_transaction(TransactionBehavior::Deferred, |tx| {
tx.query_row(query, params_from_iter(params), |row| Ok((row.get(0)?, row.get(1)?)))
.with_context(|| {
ks_err!("get_storage_stat: Error size of storage type {}", storage_type.0)
})
.no_gc()
})?;
Ok(StorageStats { storage_type, size: total, unused_size: unused })
}
fn get_total_size(&mut self) -> Result<StorageStats> {
self.do_table_size_query(
MetricsStorage::DATABASE,
"SELECT page_count * page_size, freelist_count * page_size
FROM pragma_page_count('persistent'),
pragma_page_size('persistent'),
persistent.pragma_freelist_count();",
&[],
)
}
fn get_table_size(
&mut self,
storage_type: MetricsStorage,
schema: &str,
table: &str,
) -> Result<StorageStats> {
self.do_table_size_query(
storage_type,
"SELECT pgsize,unused FROM dbstat(?1)
WHERE name=?2 AND aggregate=TRUE;",
&[schema, table],
)
}
/// Fetches a storage statistics atom for a given storage type. For storage
/// types that map to a table, information about the table's storage is
/// returned. Requests for storage types that are not DB tables return None.
pub fn get_storage_stat(&mut self, storage_type: MetricsStorage) -> Result<StorageStats> {
let _wp = wd::watch_millis_with("KeystoreDB::get_storage_stat", 500, storage_type);
match storage_type {
MetricsStorage::DATABASE => self.get_total_size(),
MetricsStorage::KEY_ENTRY => {
self.get_table_size(storage_type, "persistent", "keyentry")
}
MetricsStorage::KEY_ENTRY_ID_INDEX => {
self.get_table_size(storage_type, "persistent", "keyentry_id_index")
}
MetricsStorage::KEY_ENTRY_DOMAIN_NAMESPACE_INDEX => {
self.get_table_size(storage_type, "persistent", "keyentry_domain_namespace_index")
}
MetricsStorage::BLOB_ENTRY => {
self.get_table_size(storage_type, "persistent", "blobentry")
}
MetricsStorage::BLOB_ENTRY_KEY_ENTRY_ID_INDEX => {
self.get_table_size(storage_type, "persistent", "blobentry_keyentryid_index")
}
MetricsStorage::KEY_PARAMETER => {
self.get_table_size(storage_type, "persistent", "keyparameter")
}
MetricsStorage::KEY_PARAMETER_KEY_ENTRY_ID_INDEX => {
self.get_table_size(storage_type, "persistent", "keyparameter_keyentryid_index")
}
MetricsStorage::KEY_METADATA => {
self.get_table_size(storage_type, "persistent", "keymetadata")
}
MetricsStorage::KEY_METADATA_KEY_ENTRY_ID_INDEX => {
self.get_table_size(storage_type, "persistent", "keymetadata_keyentryid_index")
}
MetricsStorage::GRANT => self.get_table_size(storage_type, "persistent", "grant"),
MetricsStorage::AUTH_TOKEN => {
// Since the table is actually a BTreeMap now, unused_size is not meaningfully
// reportable
// Size provided is only an approximation
Ok(StorageStats {
storage_type,
size: (self.perboot.auth_tokens_len() * std::mem::size_of::<AuthTokenEntry>())
as i32,
unused_size: 0,
})
}
MetricsStorage::BLOB_METADATA => {
self.get_table_size(storage_type, "persistent", "blobmetadata")
}
MetricsStorage::BLOB_METADATA_BLOB_ENTRY_ID_INDEX => {
self.get_table_size(storage_type, "persistent", "blobmetadata_blobentryid_index")
}
_ => Err(anyhow::Error::msg(format!("Unsupported storage type: {}", storage_type.0))),
}
}
/// This function is intended to be used by the garbage collector.
/// It deletes the blobs given by `blob_ids_to_delete`. It then tries to find up to `max_blobs`
/// superseded key blobs that might need special handling by the garbage collector.
/// If no further superseded blobs can be found it deletes all other superseded blobs that don't
/// need special handling and returns None.
pub fn handle_next_superseded_blobs(
&mut self,
blob_ids_to_delete: &[i64],
max_blobs: usize,
) -> Result<Vec<SupersededBlob>> {
let _wp = wd::watch("KeystoreDB::handle_next_superseded_blob");
self.with_transaction(Immediate("TX_handle_next_superseded_blob"), |tx| {
// Delete the given blobs.
for blob_id in blob_ids_to_delete {
tx.execute(
"DELETE FROM persistent.blobmetadata WHERE blobentryid = ?;",
params![blob_id],
)
.context(ks_err!("Trying to delete blob metadata: {:?}", blob_id))?;
tx.execute("DELETE FROM persistent.blobentry WHERE id = ?;", params![blob_id])
.context(ks_err!("Trying to delete blob: {:?}", blob_id))?;
}
Self::cleanup_unreferenced(tx).context("Trying to cleanup unreferenced.")?;
// Find up to `max_blobs` more out-of-date key blobs, load their metadata and return it.
let result: Vec<(i64, Vec<u8>)> = if keystore2_flags::use_blob_state_column() {
let _wp = wd::watch("KeystoreDB::handle_next_superseded_blob find_next v2");
let mut stmt = tx
.prepare(
"SELECT id, blob FROM persistent.blobentry
WHERE subcomponent_type = ? AND state != ?
LIMIT ?;",
)
.context("Trying to prepare query for superseded blobs.")?;
let rows = stmt
.query_map(
params![SubComponentType::KEY_BLOB, BlobState::Current, max_blobs as i64],
|row| Ok((row.get(0)?, row.get(1)?)),
)
.context("Trying to query superseded blob.")?;
rows.collect::<Result<Vec<(i64, Vec<u8>)>, rusqlite::Error>>()
.context("Trying to extract superseded blobs.")?
} else {
let _wp = wd::watch("KeystoreDB::handle_next_superseded_blob find_next v1");
let mut stmt = tx
.prepare(
"SELECT id, blob FROM persistent.blobentry
WHERE subcomponent_type = ?
AND (
id NOT IN (
SELECT MAX(id) FROM persistent.blobentry
WHERE subcomponent_type = ?
GROUP BY keyentryid, subcomponent_type
)
OR keyentryid NOT IN (SELECT id FROM persistent.keyentry)
) LIMIT ?;",
)
.context("Trying to prepare query for superseded blobs.")?;
let rows = stmt
.query_map(
params![
SubComponentType::KEY_BLOB,
SubComponentType::KEY_BLOB,
max_blobs as i64,
],
|row| Ok((row.get(0)?, row.get(1)?)),
)
.context("Trying to query superseded blob.")?;
rows.collect::<Result<Vec<(i64, Vec<u8>)>, rusqlite::Error>>()
.context("Trying to extract superseded blobs.")?
};
let _wp = wd::watch("KeystoreDB::handle_next_superseded_blob load_metadata");
let result = result
.into_iter()
.map(|(blob_id, blob)| {
Ok(SupersededBlob {
blob_id,
blob,
metadata: BlobMetaData::load_from_db(blob_id, tx)?,
})
})
.collect::<Result<Vec<_>>>()
.context("Trying to load blob metadata.")?;
if !result.is_empty() {
return Ok(result).no_gc();
}
// We did not find any out-of-date key blobs, so let's remove other types of superseded
// blob in one transaction.
if keystore2_flags::use_blob_state_column() {
let _wp = wd::watch("KeystoreDB::handle_next_superseded_blob delete v2");
tx.execute(
"DELETE FROM persistent.blobentry
WHERE subcomponent_type != ? AND state != ?;",
params![SubComponentType::KEY_BLOB, BlobState::Current],
)
.context("Trying to purge out-of-date blobs (other than keyblobs)")?;
} else {
let _wp = wd::watch("KeystoreDB::handle_next_superseded_blob delete v1");
tx.execute(
"DELETE FROM persistent.blobentry
WHERE NOT subcomponent_type = ?
AND (
id NOT IN (
SELECT MAX(id) FROM persistent.blobentry
WHERE NOT subcomponent_type = ?
GROUP BY keyentryid, subcomponent_type
) OR keyentryid NOT IN (SELECT id FROM persistent.keyentry)
);",
params![SubComponentType::KEY_BLOB, SubComponentType::KEY_BLOB],
)
.context("Trying to purge superseded blobs.")?;
}
Ok(vec![]).no_gc()
})
.context(ks_err!())
}
/// This maintenance function should be called only once before the database is used for the
/// first time. It restores the invariant that `KeyLifeCycle::Existing` is a transient state.
/// The function transitions all key entries from Existing to Unreferenced unconditionally and
/// returns the number of rows affected. If this returns a value greater than 0, it means that
/// Keystore crashed at some point during key generation. Callers may want to log such
/// occurrences.
/// Unlike with `mark_unreferenced`, we don't need to purge grants, because only keys that made
/// it to `KeyLifeCycle::Live` may have grants.
pub fn cleanup_leftovers(&mut self) -> Result<usize> {
let _wp = wd::watch("KeystoreDB::cleanup_leftovers");
self.with_transaction(Immediate("TX_cleanup_leftovers"), |tx| {
tx.execute(
"UPDATE persistent.keyentry SET state = ? WHERE state = ?;",
params![KeyLifeCycle::Unreferenced, KeyLifeCycle::Existing],
)
.context("Failed to execute query.")
.need_gc()
})
.context(ks_err!())
}
/// Checks if a key exists with given key type and key descriptor properties.
pub fn key_exists(
&mut self,
domain: Domain,
nspace: i64,
alias: &str,
key_type: KeyType,
) -> Result<bool> {
let _wp = wd::watch("KeystoreDB::key_exists");
self.with_transaction(Immediate("TX_key_exists"), |tx| {
let key_descriptor =
KeyDescriptor { domain, nspace, alias: Some(alias.to_string()), blob: None };
let result = Self::load_key_entry_id(tx, &key_descriptor, key_type);
match result {
Ok(_) => Ok(true),
Err(error) => match error.root_cause().downcast_ref::<KsError>() {
Some(KsError::Rc(ResponseCode::KEY_NOT_FOUND)) => Ok(false),
_ => Err(error).context(ks_err!("Failed to find if the key exists.")),
},
}
.no_gc()
})
.context(ks_err!())
}
/// Stores a super key in the database.
pub fn store_super_key(
&mut self,
user_id: u32,
key_type: &SuperKeyType,
blob: &[u8],
blob_metadata: &BlobMetaData,
key_metadata: &KeyMetaData,
) -> Result<KeyEntry> {
let _wp = wd::watch("KeystoreDB::store_super_key");
self.with_transaction(Immediate("TX_store_super_key"), |tx| {
let key_id = Self::insert_with_retry(|id| {
tx.execute(
"INSERT into persistent.keyentry
(id, key_type, domain, namespace, alias, state, km_uuid)
VALUES(?, ?, ?, ?, ?, ?, ?);",
params![
id,
KeyType::Super,
Domain::APP.0,
user_id as i64,
key_type.alias,
KeyLifeCycle::Live,
&KEYSTORE_UUID,
],
)
})
.context("Failed to insert into keyentry table.")?;
key_metadata.store_in_db(key_id, tx).context("KeyMetaData::store_in_db failed")?;
Self::set_blob_internal(
tx,
key_id,
SubComponentType::KEY_BLOB,
Some(blob),
Some(blob_metadata),
)
.context("Failed to store key blob.")?;
Self::load_key_components(tx, KeyEntryLoadBits::KM, key_id)
.context("Trying to load key components.")
.no_gc()
})
.context(ks_err!())
}
/// Loads super key of a given user, if exists
pub fn load_super_key(
&mut self,
key_type: &SuperKeyType,
user_id: u32,
) -> Result<Option<(KeyIdGuard, KeyEntry)>> {
let _wp = wd::watch("KeystoreDB::load_super_key");
self.with_transaction(Immediate("TX_load_super_key"), |tx| {
let key_descriptor = KeyDescriptor {
domain: Domain::APP,
nspace: user_id as i64,
alias: Some(key_type.alias.into()),
blob: None,
};
let id = Self::load_key_entry_id(tx, &key_descriptor, KeyType::Super);
match id {
Ok(id) => {
let key_entry = Self::load_key_components(tx, KeyEntryLoadBits::KM, id)
.context(ks_err!("Failed to load key entry."))?;
Ok(Some((KEY_ID_LOCK.get(id), key_entry)))
}
Err(error) => match error.root_cause().downcast_ref::<KsError>() {
Some(KsError::Rc(ResponseCode::KEY_NOT_FOUND)) => Ok(None),
_ => Err(error).context(ks_err!()),
},
}
.no_gc()
})
.context(ks_err!())
}
/// Creates a transaction with the given behavior and executes f with the new transaction.
/// The transaction is committed only if f returns Ok and retried if DatabaseBusy
/// or DatabaseLocked is encountered.
fn with_transaction<T, F>(&mut self, behavior: TransactionBehavior, f: F) -> Result<T>
where
F: Fn(&Transaction) -> Result<(bool, T)>,
{
let name = behavior.name();
loop {
let result = self
.conn
.transaction_with_behavior(behavior.into())
.context(ks_err!())
.and_then(|tx| {
let _wp = name.map(wd::watch);
f(&tx).map(|result| (result, tx))
})
.and_then(|(result, tx)| {
tx.commit().context(ks_err!("Failed to commit transaction."))?;
Ok(result)
});
match result {
Ok(result) => break Ok(result),
Err(e) => {
if Self::is_locked_error(&e) {
std::thread::sleep(DB_BUSY_RETRY_INTERVAL);
continue;
} else {
return Err(e).context(ks_err!());
}
}
}
}
.map(|(need_gc, result)| {
if need_gc {
if let Some(ref gc) = self.gc {
gc.notify_gc();
}
}
result
})
}
fn is_locked_error(e: &anyhow::Error) -> bool {
matches!(
e.root_cause().downcast_ref::<rusqlite::ffi::Error>(),
Some(rusqlite::ffi::Error { code: rusqlite::ErrorCode::DatabaseBusy, .. })
| Some(rusqlite::ffi::Error { code: rusqlite::ErrorCode::DatabaseLocked, .. })
)
}
fn create_key_entry_internal(
tx: &Transaction,
domain: &Domain,
namespace: &i64,
key_type: KeyType,
km_uuid: &Uuid,
) -> Result<KeyIdGuard> {
match *domain {
Domain::APP | Domain::SELINUX => {}
_ => {
return Err(KsError::sys())
.context(ks_err!("Domain {:?} must be either App or SELinux.", domain));
}
}
Ok(KEY_ID_LOCK.get(
Self::insert_with_retry(|id| {
tx.execute(
"INSERT into persistent.keyentry
(id, key_type, domain, namespace, alias, state, km_uuid)
VALUES(?, ?, ?, ?, NULL, ?, ?);",
params![
id,
key_type,
domain.0 as u32,
*namespace,
KeyLifeCycle::Existing,
km_uuid,
],
)
})
.context(ks_err!())?,
))
}
/// Set a new blob and associates it with the given key id. Each blob
/// has a sub component type.
/// Each key can have one of each sub component type associated. If more
/// are added only the most recent can be retrieved, and superseded blobs
/// will get garbage collected.
/// Components SubComponentType::CERT and SubComponentType::CERT_CHAIN can be
/// removed by setting blob to None.
pub fn set_blob(
&mut self,
key_id: &KeyIdGuard,
sc_type: SubComponentType,
blob: Option<&[u8]>,
blob_metadata: Option<&BlobMetaData>,
) -> Result<()> {
let _wp = wd::watch("KeystoreDB::set_blob");
self.with_transaction(Immediate("TX_set_blob"), |tx| {
Self::set_blob_internal(tx, key_id.0, sc_type, blob, blob_metadata).need_gc()
})
.context(ks_err!())
}
/// Why would we insert a deleted blob? This weird function is for the purpose of legacy
/// key migration in the case where we bulk delete all the keys of an app or even a user.
/// We use this to insert key blobs into the database which can then be garbage collected
/// lazily by the key garbage collector.
pub fn set_deleted_blob(&mut self, blob: &[u8], blob_metadata: &BlobMetaData) -> Result<()> {
let _wp = wd::watch("KeystoreDB::set_deleted_blob");
self.with_transaction(Immediate("TX_set_deleted_blob"), |tx| {
Self::set_blob_internal(
tx,
Self::UNASSIGNED_KEY_ID,
SubComponentType::KEY_BLOB,
Some(blob),
Some(blob_metadata),
)
.need_gc()
})
.context(ks_err!())
}
fn set_blob_internal(
tx: &Transaction,
key_id: i64,
sc_type: SubComponentType,
blob: Option<&[u8]>,
blob_metadata: Option<&BlobMetaData>,
) -> Result<()> {
match (blob, sc_type) {
(Some(blob), _) => {
// Mark any previous blobentry(s) of the same type for the same key as superseded.
tx.execute(
"UPDATE persistent.blobentry SET state = ?
WHERE keyentryid = ? AND subcomponent_type = ?",
params![BlobState::Superseded, key_id, sc_type],
)
.context(ks_err!(
"Failed to mark prior {sc_type:?} blobentrys for {key_id} as superseded"
))?;
// Now insert the new, un-superseded, blob. (If this fails, the marking of
// old blobs as superseded will be rolled back, because we're inside a
// transaction.)
tx.execute(
"INSERT INTO persistent.blobentry
(subcomponent_type, keyentryid, blob) VALUES (?, ?, ?);",
params![sc_type, key_id, blob],
)
.context(ks_err!("Failed to insert blob."))?;
if let Some(blob_metadata) = blob_metadata {
let blob_id = tx
.query_row("SELECT MAX(id) FROM persistent.blobentry;", [], |row| {
row.get(0)
})
.context(ks_err!("Failed to get new blob id."))?;
blob_metadata
.store_in_db(blob_id, tx)
.context(ks_err!("Trying to store blob metadata."))?;
}
}
(None, SubComponentType::CERT) | (None, SubComponentType::CERT_CHAIN) => {
tx.execute(
"DELETE FROM persistent.blobentry
WHERE subcomponent_type = ? AND keyentryid = ?;",
params![sc_type, key_id],
)
.context(ks_err!("Failed to delete blob."))?;
}
(None, _) => {
return Err(KsError::sys())
.context(ks_err!("Other blobs cannot be deleted in this way."));
}
}
Ok(())
}
/// Inserts a collection of key parameters into the `persistent.keyparameter` table
/// and associates them with the given `key_id`.
#[cfg(test)]
fn insert_keyparameter(&mut self, key_id: &KeyIdGuard, params: &[KeyParameter]) -> Result<()> {
self.with_transaction(Immediate("TX_insert_keyparameter"), |tx| {
Self::insert_keyparameter_internal(tx, key_id, params).no_gc()
})
.context(ks_err!())
}
fn insert_keyparameter_internal(
tx: &Transaction,
key_id: &KeyIdGuard,
params: &[KeyParameter],
) -> Result<()> {
let mut stmt = tx
.prepare(
"INSERT into persistent.keyparameter (keyentryid, tag, data, security_level)
VALUES (?, ?, ?, ?);",
)
.context(ks_err!("Failed to prepare statement."))?;
for p in params.iter() {
stmt.insert(params![
key_id.0,
p.get_tag().0,
p.key_parameter_value(),
p.security_level().0
])
.with_context(|| ks_err!("Failed to insert {:?}", p))?;
}
Ok(())
}
/// Insert a set of key entry specific metadata into the database.
#[cfg(test)]
fn insert_key_metadata(&mut self, key_id: &KeyIdGuard, metadata: &KeyMetaData) -> Result<()> {
self.with_transaction(Immediate("TX_insert_key_metadata"), |tx| {
metadata.store_in_db(key_id.0, tx).no_gc()
})
.context(ks_err!())
}
/// Updates the alias column of the given key id `newid` with the given alias,
/// and atomically, removes the alias, domain, and namespace from another row
/// with the same alias-domain-namespace tuple if such row exits.
/// Returns Ok(true) if an old key was marked unreferenced as a hint to the garbage
/// collector.
fn rebind_alias(
tx: &Transaction,
newid: &KeyIdGuard,
alias: &str,
domain: &Domain,
namespace: &i64,
key_type: KeyType,
) -> Result<bool> {
match *domain {
Domain::APP | Domain::SELINUX => {}
_ => {
return Err(KsError::sys())
.context(ks_err!("Domain {:?} must be either App or SELinux.", domain));
}
}
let updated = tx
.execute(
"UPDATE persistent.keyentry
SET alias = NULL, domain = NULL, namespace = NULL, state = ?
WHERE alias = ? AND domain = ? AND namespace = ? AND key_type = ?;",
params![KeyLifeCycle::Unreferenced, alias, domain.0 as u32, namespace, key_type],
)
.context(ks_err!("Failed to rebind existing entry."))?;
let result = tx
.execute(
"UPDATE persistent.keyentry
SET alias = ?, state = ?
WHERE id = ? AND domain = ? AND namespace = ? AND state = ? AND key_type = ?;",
params![
alias,
KeyLifeCycle::Live,
newid.0,
domain.0 as u32,
*namespace,
KeyLifeCycle::Existing,
key_type,
],
)
.context(ks_err!("Failed to set alias."))?;
if result != 1 {
return Err(KsError::sys()).context(ks_err!(
"Expected to update a single entry but instead updated {}.",
result
));
}
Ok(updated != 0)
}
/// Moves the key given by KeyIdGuard to the new location at `destination`. If the destination
/// is already occupied by a key, this function fails with `ResponseCode::INVALID_ARGUMENT`.
pub fn migrate_key_namespace(
&mut self,
key_id_guard: KeyIdGuard,
destination: &KeyDescriptor,
caller_uid: u32,
check_permission: impl Fn(&KeyDescriptor) -> Result<()>,
) -> Result<()> {
let _wp = wd::watch("KeystoreDB::migrate_key_namespace");
let destination = match destination.domain {
Domain::APP => KeyDescriptor { nspace: caller_uid as i64, ..(*destination).clone() },
Domain::SELINUX => (*destination).clone(),
domain => {
return Err(KsError::Rc(ResponseCode::INVALID_ARGUMENT))
.context(format!("Domain {:?} must be either APP or SELINUX.", domain));
}
};
// Security critical: Must return immediately on failure. Do not remove the '?';
check_permission(&destination).context(ks_err!("Trying to check permission."))?;
let alias = destination
.alias
.as_ref()
.ok_or(KsError::Rc(ResponseCode::INVALID_ARGUMENT))
.context(ks_err!("Alias must be specified."))?;
self.with_transaction(Immediate("TX_migrate_key_namespace"), |tx| {
// Query the destination location. If there is a key, the migration request fails.
if tx
.query_row(
"SELECT id FROM persistent.keyentry
WHERE alias = ? AND domain = ? AND namespace = ?;",
params![alias, destination.domain.0, destination.nspace],
|_| Ok(()),
)
.optional()
.context("Failed to query destination.")?
.is_some()
{
return Err(KsError::Rc(ResponseCode::INVALID_ARGUMENT))
.context("Target already exists.");
}
let updated = tx
.execute(
"UPDATE persistent.keyentry
SET alias = ?, domain = ?, namespace = ?
WHERE id = ?;",
params![alias, destination.domain.0, destination.nspace, key_id_guard.id()],
)
.context("Failed to update key entry.")?;
if updated != 1 {
return Err(KsError::sys())
.context(format!("Update succeeded, but {} rows were updated.", updated));
}
Ok(()).no_gc()
})
.context(ks_err!())
}
/// Store a new key in a single transaction.
/// The function creates a new key entry, populates the blob, key parameter, and metadata
/// fields, and rebinds the given alias to the new key.
/// The boolean returned is a hint for the garbage collector. If true, a key was replaced,
/// is now unreferenced and needs to be collected.
#[allow(clippy::too_many_arguments)]
pub fn store_new_key(
&mut self,
key: &KeyDescriptor,
key_type: KeyType,
params: &[KeyParameter],
blob_info: &BlobInfo,
cert_info: &CertificateInfo,
metadata: &KeyMetaData,
km_uuid: &Uuid,
) -> Result<KeyIdGuard> {
let _wp = wd::watch("KeystoreDB::store_new_key");
let (alias, domain, namespace) = match key {
KeyDescriptor { alias: Some(alias), domain: Domain::APP, nspace, blob: None }
| KeyDescriptor { alias: Some(alias), domain: Domain::SELINUX, nspace, blob: None } => {
(alias, key.domain, nspace)
}
_ => {
return Err(KsError::Rc(ResponseCode::INVALID_ARGUMENT))
.context(ks_err!("Need alias and domain must be APP or SELINUX."));
}
};
self.with_transaction(Immediate("TX_store_new_key"), |tx| {
let key_id = Self::create_key_entry_internal(tx, &domain, namespace, key_type, km_uuid)
.context("Trying to create new key entry.")?;
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(),
SubComponentType::KEY_BLOB,
Some(blob),
Some(blob_metadata),
)
.context("Trying to insert the key blob.")?;
if let Some(cert) = &cert_info.cert {
Self::set_blob_internal(tx, key_id.id(), SubComponentType::CERT, Some(cert), None)
.context("Trying to insert the certificate.")?;
}
if let Some(cert_chain) = &cert_info.cert_chain {
Self::set_blob_internal(
tx,
key_id.id(),
SubComponentType::CERT_CHAIN,
Some(cert_chain),
None,
)
.context("Trying to insert the certificate chain.")?;
}
Self::insert_keyparameter_internal(tx, &key_id, params)
.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.")?
|| need_gc;
Ok(key_id).do_gc(need_gc)
})
.context(ks_err!())
}
/// Store a new certificate
/// The function creates a new key entry, populates the blob field and metadata, and rebinds
/// the given alias to the new cert.
pub fn store_new_certificate(
&mut self,
key: &KeyDescriptor,
key_type: KeyType,
cert: &[u8],
km_uuid: &Uuid,
) -> Result<KeyIdGuard> {
let _wp = wd::watch("KeystoreDB::store_new_certificate");
let (alias, domain, namespace) = match key {
KeyDescriptor { alias: Some(alias), domain: Domain::APP, nspace, blob: None }
| KeyDescriptor { alias: Some(alias), domain: Domain::SELINUX, nspace, blob: None } => {
(alias, key.domain, nspace)
}
_ => {
return Err(KsError::Rc(ResponseCode::INVALID_ARGUMENT))
.context(ks_err!("Need alias and domain must be APP or SELINUX."));
}
};
self.with_transaction(Immediate("TX_store_new_certificate"), |tx| {
let key_id = Self::create_key_entry_internal(tx, &domain, namespace, key_type, km_uuid)
.context("Trying to create new key entry.")?;
Self::set_blob_internal(
tx,
key_id.id(),
SubComponentType::CERT_CHAIN,
Some(cert),
None,
)
.context("Trying to insert certificate.")?;
let mut metadata = KeyMetaData::new();
metadata.add(KeyMetaEntry::CreationDate(
DateTime::now().context("Trying to make creation time.")?,
));
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.")?;
Ok(key_id).do_gc(need_gc)
})
.context(ks_err!())
}
// Helper function loading the key_id given the key descriptor
// tuple comprising domain, namespace, and alias.
// Requires a valid transaction.
fn load_key_entry_id(tx: &Transaction, key: &KeyDescriptor, key_type: KeyType) -> Result<i64> {
let alias = key
.alias
.as_ref()
.map_or_else(|| Err(KsError::sys()), Ok)
.context("In load_key_entry_id: Alias must be specified.")?;
let mut stmt = tx
.prepare(
"SELECT id FROM persistent.keyentry
WHERE
key_type = ?
AND domain = ?
AND namespace = ?
AND alias = ?
AND state = ?;",
)
.context("In load_key_entry_id: Failed to select from keyentry table.")?;
let mut rows = stmt
.query(params![key_type, key.domain.0 as u32, key.nspace, alias, KeyLifeCycle::Live])
.context("In load_key_entry_id: Failed to read from keyentry table.")?;
db_utils::with_rows_extract_one(&mut rows, |row| {
row.map_or_else(|| Err(KsError::Rc(ResponseCode::KEY_NOT_FOUND)), Ok)?
.get(0)
.context("Failed to unpack id.")
})
.context(ks_err!())
}
/// This helper function completes the access tuple of a key, which is required
/// to perform access control. The strategy depends on the `domain` field in the
/// key descriptor.
/// * Domain::SELINUX: The access tuple is complete and this function only loads
/// the key_id for further processing.
/// * Domain::APP: Like Domain::SELINUX, but the tuple is completed by `caller_uid`
/// which serves as the namespace.
/// * Domain::GRANT: The grant table is queried for the `key_id` and the
/// `access_vector`.
/// * Domain::KEY_ID: The keyentry table is queried for the owning `domain` and
/// `namespace`.
///
/// In each case the information returned is sufficient to perform the access
/// check and the key id can be used to load further key artifacts.
fn load_access_tuple(
tx: &Transaction,
key: &KeyDescriptor,
key_type: KeyType,
caller_uid: u32,
) -> Result<KeyAccessInfo> {
match key.domain {
// Domain App or SELinux. In this case we load the key_id from
// the keyentry database for further loading of key components.
// We already have the full access tuple to perform access control.
// The only distinction is that we use the caller_uid instead
// of the caller supplied namespace if the domain field is
// Domain::APP.
Domain::APP | Domain::SELINUX => {
let mut access_key = key.clone();
if access_key.domain == Domain::APP {
access_key.nspace = caller_uid as i64;
}
let key_id = Self::load_key_entry_id(tx, &access_key, key_type)
.with_context(|| format!("With key.domain = {:?}.", access_key.domain))?;
Ok(KeyAccessInfo { key_id, descriptor: access_key, vector: None })
}
// Domain::GRANT. In this case we load the key_id and the access_vector
// from the grant table.
Domain::GRANT => {
let mut stmt = tx
.prepare(
"SELECT keyentryid, access_vector FROM persistent.grant
WHERE grantee = ? AND id = ? AND
(SELECT state FROM persistent.keyentry WHERE id = keyentryid) = ?;",
)
.context("Domain::GRANT prepare statement failed")?;
let mut rows = stmt
.query(params![caller_uid as i64, key.nspace, KeyLifeCycle::Live])
.context("Domain:Grant: query failed.")?;
let (key_id, access_vector): (i64, i32) =
db_utils::with_rows_extract_one(&mut rows, |row| {
let r =
row.map_or_else(|| Err(KsError::Rc(ResponseCode::KEY_NOT_FOUND)), Ok)?;
Ok((
r.get(0).context("Failed to unpack key_id.")?,
r.get(1).context("Failed to unpack access_vector.")?,
))
})
.context("Domain::GRANT.")?;
Ok(KeyAccessInfo {
key_id,
descriptor: key.clone(),
vector: Some(access_vector.into()),
})
}
// Domain::KEY_ID. In this case we load the domain and namespace from the
// keyentry database because we need them for access control.
Domain::KEY_ID => {
let (domain, namespace): (Domain, i64) = {
let mut stmt = tx
.prepare(
"SELECT domain, namespace FROM persistent.keyentry
WHERE
id = ?
AND state = ?;",
)
.context("Domain::KEY_ID: prepare statement failed")?;
let mut rows = stmt
.query(params![key.nspace, KeyLifeCycle::Live])
.context("Domain::KEY_ID: query failed.")?;
db_utils::with_rows_extract_one(&mut rows, |row| {
let r =
row.map_or_else(|| Err(KsError::Rc(ResponseCode::KEY_NOT_FOUND)), Ok)?;
Ok((
Domain(r.get(0).context("Failed to unpack domain.")?),
r.get(1).context("Failed to unpack namespace.")?,
))
})
.context("Domain::KEY_ID.")?
};
// We may use a key by id after loading it by grant.
// In this case we have to check if the caller has a grant for this particular
// key. We can skip this if we already know that the caller is the owner.
// But we cannot know this if domain is anything but App. E.g. in the case
// of Domain::SELINUX we have to speculatively check for grants because we have to
// consult the SEPolicy before we know if the caller is the owner.
let access_vector: Option<KeyPermSet> =
if domain != Domain::APP || namespace != caller_uid as i64 {
let access_vector: Option<i32> = tx
.query_row(
"SELECT access_vector FROM persistent.grant
WHERE grantee = ? AND keyentryid = ?;",
params![caller_uid as i64, key.nspace],
|row| row.get(0),
)
.optional()
.context("Domain::KEY_ID: query grant failed.")?;
access_vector.map(|p| p.into())
} else {
None
};
let key_id = key.nspace;
let mut access_key: KeyDescriptor = key.clone();
access_key.domain = domain;
access_key.nspace = namespace;
Ok(KeyAccessInfo { key_id, descriptor: access_key, vector: access_vector })
}
_ => Err(anyhow!(KsError::Rc(ResponseCode::INVALID_ARGUMENT))),
}
}
fn load_blob_components(
key_id: i64,
load_bits: KeyEntryLoadBits,
tx: &Transaction,
) -> Result<(bool, Option<(Vec<u8>, BlobMetaData)>, Option<Vec<u8>>, Option<Vec<u8>>)> {
let mut stmt = tx
.prepare(
"SELECT MAX(id), subcomponent_type, blob FROM persistent.blobentry
WHERE keyentryid = ? GROUP BY subcomponent_type;",
)
.context(ks_err!("prepare statement failed."))?;
let mut rows = stmt.query(params![key_id]).context(ks_err!("query failed."))?;
let mut key_blob: Option<(i64, Vec<u8>)> = None;
let mut cert_blob: Option<Vec<u8>> = None;
let mut cert_chain_blob: Option<Vec<u8>> = None;
let mut has_km_blob: bool = false;
db_utils::with_rows_extract_all(&mut rows, |row| {
let sub_type: SubComponentType =
row.get(1).context("Failed to extract subcomponent_type.")?;
has_km_blob = has_km_blob || sub_type == SubComponentType::KEY_BLOB;
match (sub_type, load_bits.load_public(), load_bits.load_km()) {
(SubComponentType::KEY_BLOB, _, true) => {
key_blob = Some((
row.get(0).context("Failed to extract key blob id.")?,
row.get(2).context("Failed to extract key blob.")?,
));
}
(SubComponentType::CERT, true, _) => {
cert_blob =
Some(row.get(2).context("Failed to extract public certificate blob.")?);
}
(SubComponentType::CERT_CHAIN, true, _) => {
cert_chain_blob =
Some(row.get(2).context("Failed to extract certificate chain blob.")?);
}
(SubComponentType::CERT, _, _)
| (SubComponentType::CERT_CHAIN, _, _)
| (SubComponentType::KEY_BLOB, _, _) => {}
_ => Err(KsError::sys()).context("Unknown subcomponent type.")?,
}
Ok(())
})
.context(ks_err!())?;
let blob_info = key_blob.map_or::<Result<_>, _>(Ok(None), |(blob_id, blob)| {
Ok(Some((
blob,
BlobMetaData::load_from_db(blob_id, tx)
.context(ks_err!("Trying to load blob_metadata."))?,
)))
})?;
Ok((has_km_blob, blob_info, cert_blob, cert_chain_blob))
}
fn load_key_parameters(key_id: i64, tx: &Transaction) -> Result<Vec<KeyParameter>> {
let mut stmt = tx
.prepare(
"SELECT tag, data, security_level from persistent.keyparameter
WHERE keyentryid = ?;",
)
.context("In load_key_parameters: prepare statement failed.")?;
let mut parameters: Vec<KeyParameter> = Vec::new();
let mut rows =
stmt.query(params![key_id]).context("In load_key_parameters: query failed.")?;
db_utils::with_rows_extract_all(&mut rows, |row| {
let tag = Tag(row.get(0).context("Failed to read tag.")?);
let sec_level = SecurityLevel(row.get(2).context("Failed to read sec_level.")?);
parameters.push(
KeyParameter::new_from_sql(tag, &SqlField::new(1, row), sec_level)
.context("Failed to read KeyParameter.")?,
);
Ok(())
})
.context(ks_err!())?;
Ok(parameters)
}
/// Decrements the usage count of a limited use key. This function first checks whether the
/// usage has been exhausted, if not, decreases the usage count. If the usage count reaches
/// zero, the key also gets marked unreferenced and scheduled for deletion.
/// Returns Ok(true) if the key was marked unreferenced as a hint to the garbage collector.
pub fn check_and_update_key_usage_count(&mut self, key_id: i64) -> Result<()> {
let _wp = wd::watch("KeystoreDB::check_and_update_key_usage_count");
self.with_transaction(Immediate("TX_check_and_update_key_usage_count"), |tx| {
let limit: Option<i32> = tx
.query_row(
"SELECT data FROM persistent.keyparameter WHERE keyentryid = ? AND tag = ?;",
params![key_id, Tag::USAGE_COUNT_LIMIT.0],
|row| row.get(0),
)
.optional()
.context("Trying to load usage count")?;
let limit = limit
.ok_or(KsError::Km(ErrorCode::INVALID_KEY_BLOB))
.context("The Key no longer exists. Key is exhausted.")?;
tx.execute(
"UPDATE persistent.keyparameter
SET data = data - 1
WHERE keyentryid = ? AND tag = ? AND data > 0;",
params![key_id, Tag::USAGE_COUNT_LIMIT.0],
)
.context("Failed to update key usage count.")?;
match limit {
1 => Self::mark_unreferenced(tx, key_id)
.map(|need_gc| (need_gc, ()))
.context("Trying to mark limited use key for deletion."),
0 => Err(KsError::Km(ErrorCode::INVALID_KEY_BLOB)).context("Key is exhausted."),
_ => Ok(()).no_gc(),
}
})
.context(ks_err!())
}
/// Load a key entry by the given key descriptor.
/// It uses the `check_permission` callback to verify if the access is allowed
/// given the key access tuple read from the database using `load_access_tuple`.
/// With `load_bits` the caller may specify which blobs shall be loaded from
/// the blob database.
pub fn load_key_entry(
&mut self,
key: &KeyDescriptor,
key_type: KeyType,
load_bits: KeyEntryLoadBits,
caller_uid: u32,
check_permission: impl Fn(&KeyDescriptor, Option<KeyPermSet>) -> Result<()>,
) -> Result<(KeyIdGuard, KeyEntry)> {
let _wp = wd::watch("KeystoreDB::load_key_entry");
loop {
match self.load_key_entry_internal(
key,
key_type,
load_bits,
caller_uid,
&check_permission,
) {
Ok(result) => break Ok(result),
Err(e) => {
if Self::is_locked_error(&e) {
std::thread::sleep(DB_BUSY_RETRY_INTERVAL);
continue;
} else {
return Err(e).context(ks_err!());
}
}
}
}
}
fn load_key_entry_internal(
&mut self,
key: &KeyDescriptor,
key_type: KeyType,
load_bits: KeyEntryLoadBits,
caller_uid: u32,
check_permission: &impl Fn(&KeyDescriptor, Option<KeyPermSet>) -> Result<()>,
) -> Result<(KeyIdGuard, KeyEntry)> {
// KEY ID LOCK 1/2
// If we got a key descriptor with a key id we can get the lock right away.
// Otherwise we have to defer it until we know the key id.
let key_id_guard = match key.domain {
Domain::KEY_ID => Some(KEY_ID_LOCK.get(key.nspace)),
_ => None,
};
let tx = self
.conn
.unchecked_transaction()
.context(ks_err!("Failed to initialize transaction."))?;
// Load the key_id and complete the access control tuple.
let access = Self::load_access_tuple(&tx, key, key_type, caller_uid).context(ks_err!())?;
// Perform access control. It is vital that we return here if the permission is denied.
// So do not touch that '?' at the end.
check_permission(&access.descriptor, access.vector).context(ks_err!())?;
// KEY ID LOCK 2/2
// If we did not get a key id lock by now, it was because we got a key descriptor
// without a key id. At this point we got the key id, so we can try and get a lock.
// However, we cannot block here, because we are in the middle of the transaction.
// So first we try to get the lock non blocking. If that fails, we roll back the
// transaction and block until we get the lock. After we successfully got the lock,
// we start a new transaction and load the access tuple again.
//
// We don't need to perform access control again, because we already established
// that the caller had access to the given key. But we need to make sure that the
// key id still exists. So we have to load the key entry by key id this time.
let (key_id_guard, tx) = match key_id_guard {
None => match KEY_ID_LOCK.try_get(access.key_id) {
None => {
// Roll back the transaction.
tx.rollback().context(ks_err!("Failed to roll back transaction."))?;
// Block until we have a key id lock.
let key_id_guard = KEY_ID_LOCK.get(access.key_id);
// Create a new transaction.
let tx = self
.conn
.unchecked_transaction()
.context(ks_err!("Failed to initialize transaction."))?;
Self::load_access_tuple(
&tx,
// This time we have to load the key by the retrieved key id, because the
// alias may have been rebound after we rolled back the transaction.
&KeyDescriptor {
domain: Domain::KEY_ID,
nspace: access.key_id,
..Default::default()
},
key_type,
caller_uid,
)
.context(ks_err!("(deferred key lock)"))?;
(key_id_guard, tx)
}
Some(l) => (l, tx),
},
Some(key_id_guard) => (key_id_guard, tx),
};
let key_entry =
Self::load_key_components(&tx, load_bits, key_id_guard.id()).context(ks_err!())?;
tx.commit().context(ks_err!("Failed to commit transaction."))?;
Ok((key_id_guard, key_entry))
}
fn mark_unreferenced(tx: &Transaction, key_id: i64) -> Result<bool> {
let updated = tx
.execute("DELETE FROM persistent.keyentry WHERE id = ?;", params![key_id])
.context("Trying to delete keyentry.")?;
tx.execute("DELETE FROM persistent.keymetadata WHERE keyentryid = ?;", params![key_id])
.context("Trying to delete keymetadata.")?;
tx.execute("DELETE FROM persistent.keyparameter WHERE keyentryid = ?;", params![key_id])
.context("Trying to delete keyparameters.")?;
tx.execute("DELETE FROM persistent.grant WHERE keyentryid = ?;", params![key_id])
.context("Trying to delete grants.")?;
// The associated blobentry rows are not immediately deleted when the owning keyentry is
// removed, because a KeyMint `deleteKey()` invocation is needed (specifically for the
// `KEY_BLOB`). Mark the affected rows with `state=Orphaned` so a subsequent garbage
// collection can do this.
tx.execute(
"UPDATE persistent.blobentry SET state = ? WHERE keyentryid = ?",
params![BlobState::Orphaned, key_id],
)
.context("Trying to mark blobentrys as superseded")?;
Ok(updated != 0)
}
/// Marks the given key as unreferenced and removes all of the grants to this key.
/// Returns Ok(true) if a key was marked unreferenced as a hint for the garbage collector.
pub fn unbind_key(
&mut self,
key: &KeyDescriptor,
key_type: KeyType,
caller_uid: u32,
check_permission: impl Fn(&KeyDescriptor, Option<KeyPermSet>) -> Result<()>,
) -> Result<()> {
let _wp = wd::watch("KeystoreDB::unbind_key");
self.with_transaction(Immediate("TX_unbind_key"), |tx| {
let access = Self::load_access_tuple(tx, key, key_type, caller_uid)
.context("Trying to get access tuple.")?;
// Perform access control. It is vital that we return here if the permission is denied.
// So do not touch that '?' at the end.
check_permission(&access.descriptor, access.vector)
.context("While checking permission.")?;
Self::mark_unreferenced(tx, access.key_id)
.map(|need_gc| (need_gc, ()))
.context("Trying to mark the key unreferenced.")
})
.context(ks_err!())
}
fn get_key_km_uuid(tx: &Transaction, key_id: i64) -> Result<Uuid> {
tx.query_row(
"SELECT km_uuid FROM persistent.keyentry WHERE id = ?",
params![key_id],
|row| row.get(0),
)
.context(ks_err!())
}
/// Delete all artifacts belonging to the namespace given by the domain-namespace tuple.
/// This leaves all of the blob entries orphaned for subsequent garbage collection.
pub fn unbind_keys_for_namespace(&mut self, domain: Domain, namespace: i64) -> Result<()> {
let _wp = wd::watch("KeystoreDB::unbind_keys_for_namespace");
if !(domain == Domain::APP || domain == Domain::SELINUX) {
return Err(KsError::Rc(ResponseCode::INVALID_ARGUMENT)).context(ks_err!());
}
self.with_transaction(Immediate("TX_unbind_keys_for_namespace"), |tx| {
tx.execute(
"DELETE FROM persistent.keymetadata
WHERE keyentryid IN (
SELECT id FROM persistent.keyentry
WHERE domain = ? AND namespace = ? AND key_type = ?
);",
params![domain.0, namespace, KeyType::Client],
)
.context("Trying to delete keymetadata.")?;
tx.execute(
"DELETE FROM persistent.keyparameter
WHERE keyentryid IN (
SELECT id FROM persistent.keyentry
WHERE domain = ? AND namespace = ? AND key_type = ?
);",
params![domain.0, namespace, KeyType::Client],
)
.context("Trying to delete keyparameters.")?;
tx.execute(
"DELETE FROM persistent.grant
WHERE keyentryid IN (
SELECT id FROM persistent.keyentry
WHERE domain = ? AND namespace = ? AND key_type = ?
);",
params![domain.0, namespace, KeyType::Client],
)
.context("Trying to delete grants.")?;
tx.execute(
"DELETE FROM persistent.keyentry
WHERE domain = ? AND namespace = ? AND key_type = ?;",
params![domain.0, namespace, KeyType::Client],
)
.context("Trying to delete keyentry.")?;
Ok(()).need_gc()
})
.context(ks_err!())
}
fn cleanup_unreferenced(tx: &Transaction) -> Result<()> {
let _wp = wd::watch("KeystoreDB::cleanup_unreferenced");
{
tx.execute(
"DELETE FROM persistent.keymetadata
WHERE keyentryid IN (
SELECT id FROM persistent.keyentry
WHERE state = ?
);",
params![KeyLifeCycle::Unreferenced],
)
.context("Trying to delete keymetadata.")?;
tx.execute(
"DELETE FROM persistent.keyparameter
WHERE keyentryid IN (
SELECT id FROM persistent.keyentry
WHERE state = ?
);",
params![KeyLifeCycle::Unreferenced],
)
.context("Trying to delete keyparameters.")?;
tx.execute(
"DELETE FROM persistent.grant
WHERE keyentryid IN (
SELECT id FROM persistent.keyentry
WHERE state = ?
);",
params![KeyLifeCycle::Unreferenced],
)
.context("Trying to delete grants.")?;
tx.execute(
"DELETE FROM persistent.keyentry
WHERE state = ?;",
params![KeyLifeCycle::Unreferenced],
)
.context("Trying to delete keyentry.")?;
Result::<()>::Ok(())
}
.context(ks_err!())
}
/// Deletes all keys for the given user, including both client keys and super keys.
pub fn unbind_keys_for_user(&mut self, user_id: u32) -> Result<()> {
let _wp = wd::watch("KeystoreDB::unbind_keys_for_user");
self.with_transaction(Immediate("TX_unbind_keys_for_user"), |tx| {
let mut stmt = tx
.prepare(&format!(
"SELECT id from persistent.keyentry
WHERE (
key_type = ?
AND domain = ?
AND cast ( (namespace/{aid_user_offset}) as int) = ?
AND state = ?
) OR (
key_type = ?
AND namespace = ?
AND state = ?
);",
aid_user_offset = AID_USER_OFFSET
))
.context(concat!(
"In unbind_keys_for_user. ",
"Failed to prepare the query to find the keys created by apps."
))?;
let mut rows = stmt
.query(params![
// WHERE client key:
KeyType::Client,
Domain::APP.0 as u32,
user_id,
KeyLifeCycle::Live,
// OR super key:
KeyType::Super,
user_id,
KeyLifeCycle::Live
])
.context(ks_err!("Failed to query the keys created by apps."))?;
let mut key_ids: Vec<i64> = Vec::new();
db_utils::with_rows_extract_all(&mut rows, |row| {
key_ids
.push(row.get(0).context("Failed to read key id of a key created by an app.")?);
Ok(())
})
.context(ks_err!())?;
let mut notify_gc = false;
for key_id in key_ids {
notify_gc = Self::mark_unreferenced(tx, key_id)
.context("In unbind_keys_for_user.")?
|| notify_gc;
}
Ok(()).do_gc(notify_gc)
})
.context(ks_err!())
}
/// Deletes all auth-bound keys, i.e. keys that require user authentication, for the given user.
/// This runs when the user's lock screen is being changed to Swipe or None.
///
/// This intentionally does *not* delete keys that require that the device be unlocked, unless
/// such keys also require user authentication. Keystore's concept of user authentication is
/// fairly strong, and it requires that keys that require authentication be deleted as soon as
/// authentication is no longer possible. In contrast, keys that just require that the device
/// be unlocked should remain usable when the lock screen is set to Swipe or None, as the device
/// is always considered "unlocked" in that case.
pub fn unbind_auth_bound_keys_for_user(&mut self, user_id: u32) -> Result<()> {
let _wp = wd::watch("KeystoreDB::unbind_auth_bound_keys_for_user");
self.with_transaction(Immediate("TX_unbind_auth_bound_keys_for_user"), |tx| {
let mut stmt = tx
.prepare(&format!(
"SELECT id from persistent.keyentry
WHERE key_type = ?
AND domain = ?
AND cast ( (namespace/{aid_user_offset}) as int) = ?
AND state = ?;",
aid_user_offset = AID_USER_OFFSET
))
.context(concat!(
"In unbind_auth_bound_keys_for_user. ",
"Failed to prepare the query to find the keys created by apps."
))?;
let mut rows = stmt
.query(params![KeyType::Client, Domain::APP.0 as u32, user_id, KeyLifeCycle::Live,])
.context(ks_err!("Failed to query the keys created by apps."))?;
let mut key_ids: Vec<i64> = Vec::new();
db_utils::with_rows_extract_all(&mut rows, |row| {
key_ids
.push(row.get(0).context("Failed to read key id of a key created by an app.")?);
Ok(())
})
.context(ks_err!())?;
let mut notify_gc = false;
let mut num_unbound = 0;
for key_id in key_ids {
// Load the key parameters and filter out non-auth-bound keys. To identify
// auth-bound keys, use the presence of UserSecureID. The absence of NoAuthRequired
// could also be used, but UserSecureID is what Keystore treats as authoritative
// when actually enforcing the key parameters (it might not matter, though).
let params = Self::load_key_parameters(key_id, tx)
.context("Failed to load key parameters.")?;
let is_auth_bound_key = params.iter().any(|kp| {
matches!(kp.key_parameter_value(), KeyParameterValue::UserSecureID(_))
});
if is_auth_bound_key {
notify_gc = Self::mark_unreferenced(tx, key_id)
.context("In unbind_auth_bound_keys_for_user.")?
|| notify_gc;
num_unbound += 1;
}
}
log::info!("Deleting {num_unbound} auth-bound keys for user {user_id}");
Ok(()).do_gc(notify_gc)
})
.context(ks_err!())
}
fn load_key_components(
tx: &Transaction,
load_bits: KeyEntryLoadBits,
key_id: i64,
) -> Result<KeyEntry> {
let metadata = KeyMetaData::load_from_db(key_id, tx).context("In load_key_components.")?;
let (has_km_blob, key_blob_info, cert_blob, cert_chain_blob) =
Self::load_blob_components(key_id, load_bits, tx).context("In load_key_components.")?;
let parameters = Self::load_key_parameters(key_id, tx)
.context("In load_key_components: Trying to load key parameters.")?;
let km_uuid = Self::get_key_km_uuid(tx, key_id)
.context("In load_key_components: Trying to get KM uuid.")?;
Ok(KeyEntry {
id: key_id,
key_blob_info,
cert: cert_blob,
cert_chain: cert_chain_blob,
km_uuid,
parameters,
metadata,
pure_cert: !has_km_blob,
})
}
/// Returns a list of KeyDescriptors in the selected domain/namespace whose
/// aliases are greater than the specified 'start_past_alias'. If no value
/// is provided, returns all KeyDescriptors.
/// The key descriptors will have the domain, nspace, and alias field set.
/// The returned list will be sorted by alias.
/// Domain must be APP or SELINUX, the caller must make sure of that.
/// Number of returned values is limited to 10,000 (which is empirically roughly
/// what will fit in a Binder message).
pub fn list_past_alias(
&mut self,
domain: Domain,
namespace: i64,
key_type: KeyType,
start_past_alias: Option<&str>,
) -> Result<Vec<KeyDescriptor>> {
let _wp = wd::watch("KeystoreDB::list_past_alias");
let query = format!(
"SELECT DISTINCT alias FROM persistent.keyentry
WHERE domain = ?
AND namespace = ?
AND alias IS NOT NULL
AND state = ?
AND key_type = ?
{}
ORDER BY alias ASC
LIMIT 10000;",
if start_past_alias.is_some() { " AND alias > ?" } else { "" }
);
self.with_transaction(TransactionBehavior::Deferred, |tx| {
let mut stmt = tx.prepare(&query).context(ks_err!("Failed to prepare."))?;
let mut rows = match start_past_alias {
Some(past_alias) => stmt
.query(params![
domain.0 as u32,
namespace,
KeyLifeCycle::Live,
key_type,
past_alias
])
.context(ks_err!("Failed to query."))?,
None => stmt
.query(params![domain.0 as u32, namespace, KeyLifeCycle::Live, key_type,])
.context(ks_err!("Failed to query."))?,
};
let mut descriptors: Vec<KeyDescriptor> = Vec::new();
db_utils::with_rows_extract_all(&mut rows, |row| {
descriptors.push(KeyDescriptor {
domain,
nspace: namespace,
alias: Some(row.get(0).context("Trying to extract alias.")?),
blob: None,
});
Ok(())
})
.context(ks_err!("Failed to extract rows."))?;
Ok(descriptors).no_gc()
})
}
/// Returns a number of KeyDescriptors in the selected domain/namespace.
/// Domain must be APP or SELINUX, the caller must make sure of that.
pub fn count_keys(
&mut self,
domain: Domain,
namespace: i64,
key_type: KeyType,
) -> Result<usize> {
let _wp = wd::watch("KeystoreDB::countKeys");
let num_keys = self.with_transaction(TransactionBehavior::Deferred, |tx| {
tx.query_row(
"SELECT COUNT(alias) FROM persistent.keyentry
WHERE domain = ?
AND namespace = ?
AND alias IS NOT NULL
AND state = ?
AND key_type = ?;",
params![domain.0 as u32, namespace, KeyLifeCycle::Live, key_type],
|row| row.get(0),
)
.context(ks_err!("Failed to count number of keys."))
.no_gc()
})?;
Ok(num_keys)
}
/// Adds a grant to the grant table.
/// Like `load_key_entry` this function loads the access tuple before
/// it uses the callback for a permission check. Upon success,
/// it inserts the `grantee_uid`, `key_id`, and `access_vector` into the
/// grant table. The new row will have a randomized id, which is used as
/// grant id in the namespace field of the resulting KeyDescriptor.
pub fn grant(
&mut self,
key: &KeyDescriptor,
caller_uid: u32,
grantee_uid: u32,
access_vector: KeyPermSet,
check_permission: impl Fn(&KeyDescriptor, &KeyPermSet) -> Result<()>,
) -> Result<KeyDescriptor> {
let _wp = wd::watch("KeystoreDB::grant");
self.with_transaction(Immediate("TX_grant"), |tx| {
// Load the key_id and complete the access control tuple.
// We ignore the access vector here because grants cannot be granted.
// The access vector returned here expresses the permissions the
// grantee has if key.domain == Domain::GRANT. But this vector
// cannot include the grant permission by design, so there is no way the
// subsequent permission check can pass.
// We could check key.domain == Domain::GRANT and fail early.
// But even if we load the access tuple by grant here, the permission
// check denies the attempt to create a grant by grant descriptor.
let access =
Self::load_access_tuple(tx, key, KeyType::Client, caller_uid).context(ks_err!())?;
// Perform access control. It is vital that we return here if the permission
// was denied. So do not touch that '?' at the end of the line.
// This permission check checks if the caller has the grant permission
// for the given key and in addition to all of the permissions
// expressed in `access_vector`.
check_permission(&access.descriptor, &access_vector)
.context(ks_err!("check_permission failed"))?;
let grant_id = if let Some(grant_id) = tx
.query_row(
"SELECT id FROM persistent.grant
WHERE keyentryid = ? AND grantee = ?;",
params![access.key_id, grantee_uid],
|row| row.get(0),
)
.optional()
.context(ks_err!("Failed get optional existing grant id."))?
{
tx.execute(
"UPDATE persistent.grant
SET access_vector = ?
WHERE id = ?;",
params![i32::from(access_vector), grant_id],
)
.context(ks_err!("Failed to update existing grant."))?;
grant_id
} else {
Self::insert_with_retry(|id| {
tx.execute(
"INSERT INTO persistent.grant (id, grantee, keyentryid, access_vector)
VALUES (?, ?, ?, ?);",
params![id, grantee_uid, access.key_id, i32::from(access_vector)],
)
})
.context(ks_err!())?
};
Ok(KeyDescriptor { domain: Domain::GRANT, nspace: grant_id, alias: None, blob: None })
.no_gc()
})
}
/// This function checks permissions like `grant` and `load_key_entry`
/// before removing a grant from the grant table.
pub fn ungrant(
&mut self,
key: &KeyDescriptor,
caller_uid: u32,
grantee_uid: u32,
check_permission: impl Fn(&KeyDescriptor) -> Result<()>,
) -> Result<()> {
let _wp = wd::watch("KeystoreDB::ungrant");
self.with_transaction(Immediate("TX_ungrant"), |tx| {
// Load the key_id and complete the access control tuple.
// We ignore the access vector here because grants cannot be granted.
let access =
Self::load_access_tuple(tx, key, KeyType::Client, caller_uid).context(ks_err!())?;
// Perform access control. We must return here if the permission
// was denied. So do not touch the '?' at the end of this line.
check_permission(&access.descriptor).context(ks_err!("check_permission failed."))?;
tx.execute(
"DELETE FROM persistent.grant
WHERE keyentryid = ? AND grantee = ?;",
params![access.key_id, grantee_uid],
)
.context("Failed to delete grant.")?;
Ok(()).no_gc()
})
}
// Generates a random id and passes it to the given function, which will
// try to insert it into a database. If that insertion fails, retry;
// otherwise return the id.
fn insert_with_retry(inserter: impl Fn(i64) -> rusqlite::Result<usize>) -> Result<i64> {
loop {
let newid: i64 = match random() {
Self::UNASSIGNED_KEY_ID => continue, // UNASSIGNED_KEY_ID cannot be assigned.
i => i,
};
match inserter(newid) {
// If the id already existed, try again.
Err(rusqlite::Error::SqliteFailure(
libsqlite3_sys::Error {
code: libsqlite3_sys::ErrorCode::ConstraintViolation,
extended_code: libsqlite3_sys::SQLITE_CONSTRAINT_UNIQUE,
},
_,
)) => (),
Err(e) => {
return Err(e).context(ks_err!("failed to insert into database."));
}
_ => return Ok(newid),
}
}
}
/// Insert or replace the auth token based on (user_id, auth_id, auth_type)
pub fn insert_auth_token(&mut self, auth_token: &HardwareAuthToken) {
self.perboot
.insert_auth_token_entry(AuthTokenEntry::new(auth_token.clone(), BootTime::now()))
}
/// Find the newest auth token matching the given predicate.
pub fn find_auth_token_entry<F>(&self, p: F) -> Option<AuthTokenEntry>
where
F: Fn(&AuthTokenEntry) -> bool,
{
self.perboot.find_auth_token_entry(p)
}
/// Load descriptor of a key by key id
pub fn load_key_descriptor(&mut self, key_id: i64) -> Result<Option<KeyDescriptor>> {
let _wp = wd::watch("KeystoreDB::load_key_descriptor");
self.with_transaction(TransactionBehavior::Deferred, |tx| {
tx.query_row(
"SELECT domain, namespace, alias FROM persistent.keyentry WHERE id = ?;",
params![key_id],
|row| {
Ok(KeyDescriptor {
domain: Domain(row.get(0)?),
nspace: row.get(1)?,
alias: row.get(2)?,
blob: None,
})
},
)
.optional()
.context("Trying to load key descriptor")
.no_gc()
})
.context(ks_err!())
}
/// Returns a list of app UIDs that have keys authenticated by the given secure_user_id
/// (for the given user_id).
/// This is helpful for finding out which apps will have their keys invalidated when
/// the user changes biometrics enrollment or removes their LSKF.
pub fn get_app_uids_affected_by_sid(
&mut self,
user_id: i32,
secure_user_id: i64,
) -> Result<Vec<i64>> {
let _wp = wd::watch("KeystoreDB::get_app_uids_affected_by_sid");
let ids = self.with_transaction(Immediate("TX_get_app_uids_affected_by_sid"), |tx| {
let mut stmt = tx
.prepare(&format!(
"SELECT id, namespace from persistent.keyentry
WHERE key_type = ?
AND domain = ?
AND cast ( (namespace/{AID_USER_OFFSET}) as int) = ?
AND state = ?;",
))
.context(concat!(
"In get_app_uids_affected_by_sid, ",
"failed to prepare the query to find the keys created by apps."
))?;
let mut rows = stmt
.query(params![KeyType::Client, Domain::APP.0 as u32, user_id, KeyLifeCycle::Live,])
.context(ks_err!("Failed to query the keys created by apps."))?;
let mut key_ids_and_app_uids: HashMap<i64, i64> = Default::default();
db_utils::with_rows_extract_all(&mut rows, |row| {
key_ids_and_app_uids.insert(
row.get(0).context("Failed to read key id of a key created by an app.")?,
row.get(1).context("Failed to read the app uid")?,
);
Ok(())
})?;
Ok(key_ids_and_app_uids).no_gc()
})?;
let mut app_uids_affected_by_sid: HashSet<i64> = Default::default();
for (key_id, app_uid) in ids {
// Read the key parameters for each key in its own transaction. It is OK to ignore
// an error to get the properties of a particular key since it might have been deleted
// under our feet after the previous transaction concluded. If the key was deleted
// then it is no longer applicable if it was auth-bound or not.
if let Ok(is_key_bound_to_sid) =
self.with_transaction(Immediate("TX_get_app_uids_affects_by_sid 2"), |tx| {
let params = Self::load_key_parameters(key_id, tx)
.context("Failed to load key parameters.")?;
// Check if the key is bound to this secure user ID.
let is_key_bound_to_sid = params.iter().any(|kp| {
matches!(
kp.key_parameter_value(),
KeyParameterValue::UserSecureID(sid) if *sid == secure_user_id
)
});
Ok(is_key_bound_to_sid).no_gc()
})
{
if is_key_bound_to_sid {
app_uids_affected_by_sid.insert(app_uid);
}
}
}
let app_uids_vec: Vec<i64> = app_uids_affected_by_sid.into_iter().collect();
Ok(app_uids_vec)
}
}