// Copyright (C) 2009 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.
package com.google.gerrit.sshd;
import static com.google.gerrit.reviewdb.client.AccountExternalId.SCHEME_USERNAME;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import com.google.gerrit.common.errors.InvalidSshKeyException;
import com.google.gerrit.reviewdb.client.AccountExternalId;
import com.google.gerrit.reviewdb.client.AccountSshKey;
import com.google.gerrit.reviewdb.server.ReviewDb;
import com.google.gerrit.server.cache.CacheModule;
import com.google.gerrit.server.ssh.SshKeyCache;
import com.google.gwtorm.server.OrmException;
import com.google.gwtorm.server.SchemaFactory;
import com.google.inject.Inject;
import com.google.inject.Module;
import com.google.inject.Singleton;
import com.google.inject.TypeLiteral;
import com.google.inject.name.Named;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.spec.InvalidKeySpecException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ExecutionException;
/** Provides the {@link SshKeyCacheEntry}. */
@Singleton
public class SshKeyCacheImpl implements SshKeyCache {
private static final Logger log =
LoggerFactory.getLogger(SshKeyCacheImpl.class);
private static final String CACHE_NAME = "sshkeys";
static final Iterable<SshKeyCacheEntry> NO_SUCH_USER = none();
static final Iterable<SshKeyCacheEntry> NO_KEYS = none();
public static Module module() {
return new CacheModule() {
@Override
protected void configure() {
cache(CACHE_NAME,
String.class,
new TypeLiteral<Iterable<SshKeyCacheEntry>>(){})
.loader(Loader.class);
bind(SshKeyCacheImpl.class);
bind(SshKeyCache.class).to(SshKeyCacheImpl.class);
}
};
}
private static Iterable<SshKeyCacheEntry> none() {
return Collections.unmodifiableCollection(Arrays
.asList(new SshKeyCacheEntry[0]));
}
private final LoadingCache<String, Iterable<SshKeyCacheEntry>> cache;
@Inject
SshKeyCacheImpl(
@Named(CACHE_NAME) LoadingCache<String, Iterable<SshKeyCacheEntry>> cache) {
this.cache = cache;
}
Iterable<SshKeyCacheEntry> get(String username) {
try {
return cache.get(username);
} catch (ExecutionException e) {
log.warn("Cannot load SSH keys for " + username, e);
return Collections.emptyList();
}
}
public void evict(String username) {
if (username != null) {
cache.invalidate(username);
}
}
@Override
public AccountSshKey create(AccountSshKey.Id id, String encoded)
throws InvalidSshKeyException {
try {
final AccountSshKey key =
new AccountSshKey(id, SshUtil.toOpenSshPublicKey(encoded));
SshUtil.parse(key);
return key;
} catch (NoSuchAlgorithmException e) {
throw new InvalidSshKeyException();
} catch (InvalidKeySpecException e) {
throw new InvalidSshKeyException();
} catch (NoSuchProviderException e) {
log.error("Cannot parse SSH key", e);
throw new InvalidSshKeyException();
}
}
static class Loader extends CacheLoader<String, Iterable<SshKeyCacheEntry>> {
private final SchemaFactory<ReviewDb> schema;
@Inject
Loader(SchemaFactory<ReviewDb> schema) {
this.schema = schema;
}
@Override
public Iterable<SshKeyCacheEntry> load(String username) throws Exception {
final ReviewDb db = schema.open();
try {
final AccountExternalId.Key key =
new AccountExternalId.Key(SCHEME_USERNAME, username);
final AccountExternalId user = db.accountExternalIds().get(key);
if (user == null) {
return NO_SUCH_USER;
}
final List<SshKeyCacheEntry> kl = new ArrayList<SshKeyCacheEntry>(4);
for (AccountSshKey k : db.accountSshKeys().byAccount(
user.getAccountId())) {
if (k.isValid()) {
add(db, kl, k);
}
}
if (kl.isEmpty()) {
return NO_KEYS;
}
return Collections.unmodifiableList(kl);
} finally {
db.close();
}
}
private void add(ReviewDb db, List<SshKeyCacheEntry> kl, AccountSshKey k) {
try {
kl.add(new SshKeyCacheEntry(k.getKey(), SshUtil.parse(k)));
} catch (OutOfMemoryError e) {
// This is the only case where we assume the problem has nothing
// to do with the key object, and instead we must abort this load.
//
throw e;
} catch (Throwable e) {
markInvalid(db, k);
}
}
private void markInvalid(final ReviewDb db, final AccountSshKey k) {
try {
log.info("Flagging SSH key " + k.getKey() + " invalid");
k.setInvalid();
db.accountSshKeys().update(Collections.singleton(k));
} catch (OrmException e) {
log.error("Failed to mark SSH key" + k.getKey() + " invalid", e);
}
}
}
}