storage: enable switching env through encryption flags

Makefile

@@ -915,7 +915,7 @@ UI_JS := $(UI_ROOT)/src/js/protos.js
 UI_TS := $(UI_ROOT)/src/js/protos.d.ts
 UI_PROTOS := $(UI_JS) $(UI_TS)
 
-CPP_PROTOS := $(filter %/roachpb/metadata.proto %/roachpb/data.proto %/roachpb/internal.proto %/engine/enginepb/mvcc.proto %/engine/enginepb/mvcc3.proto %/engine/enginepb/rocksdb.proto %/hlc/legacy_timestamp.proto %/hlc/timestamp.proto %/unresolved_addr.proto,$(GO_PROTOS))
+CPP_PROTOS := $(filter %/roachpb/metadata.proto %/roachpb/data.proto %/roachpb/internal.proto %/engine/enginepb/mvcc.proto %/engine/enginepb/mvcc3.proto %/engine/enginepb/registry.proto %/engine/enginepb/rocksdb.proto %/hlc/legacy_timestamp.proto %/hlc/timestamp.proto %/unresolved_addr.proto,$(GO_PROTOS))
 CPP_HEADERS := $(subst $(PKG_ROOT),$(CPP_PROTO_ROOT),$(CPP_PROTOS:%.proto=%.pb.h))
 CPP_SOURCES := $(subst $(PKG_ROOT),$(CPP_PROTO_ROOT),$(CPP_PROTOS:%.proto=%.pb.cc))
 

c-deps/libroach/CMakeLists.txt

@@ -23,12 +23,14 @@ project(roachlib)
 add_library(roach
   db.cc
   encoding.cc
+  env_switching.cc
   eventlistener.cc
   protos/roachpb/data.pb.cc
   protos/roachpb/internal.pb.cc
   protos/roachpb/metadata.pb.cc
   protos/storage/engine/enginepb/mvcc.pb.cc
   protos/storage/engine/enginepb/mvcc3.pb.cc
+  protos/storage/engine/enginepb/registry.pb.cc
   protos/storage/engine/enginepb/rocksdb.pb.cc
   protos/util/hlc/legacy_timestamp.pb.cc
   protos/util/hlc/timestamp.pb.cc

c-deps/libroach/db.cc

@@ -33,6 +33,7 @@
 #include "protos/storage/engine/enginepb/mvcc.pb.h"
 #include "db.h"
 #include "encoding.h"
+#include "env_switching.h"
 #include "eventlistener.h"
 #include "keys.h"
 
@@ -89,17 +90,19 @@ struct DBEngine {
 };
 
 struct DBImpl : public DBEngine {
+  std::unique_ptr<rocksdb::Env> switching_env;
   std::unique_ptr<rocksdb::Env> memenv;
   std::unique_ptr<rocksdb::DB> rep_deleter;
   std::shared_ptr<rocksdb::Cache> block_cache;
   std::shared_ptr<DBEventListener> event_listener;
 
-  // Construct a new DBImpl from the specified DB and Env. Both the DB
-  // and Env will be deleted when the DBImpl is deleted. It is ok to
-  // pass NULL for the Env.
+  // Construct a new DBImpl from the specified DB.
+  // The DB and passed Envs will be deleted when the DBImpl is deleted.
+  // Either env can be NULL.
   DBImpl(rocksdb::DB* r, rocksdb::Env* m, std::shared_ptr<rocksdb::Cache> bc,
-    std::shared_ptr<DBEventListener> event_listener)
+    std::shared_ptr<DBEventListener> event_listener, rocksdb::Env* s_env)
       : DBEngine(r),
+        switching_env(s_env),
         memenv(m),
         rep_deleter(r),
         block_cache(bc),
@@ -1691,20 +1694,29 @@ DBStatus DBOpen(DBEngine **db, DBSlice dir, DBOptions db_opts) {
   std::shared_ptr<DBEventListener> event_listener(new DBEventListener);
   options.listeners.emplace_back(event_listener);
 
+  // TODO(mberhault): we shouldn't need two separate env objects,
+  // options.env should be sufficient with SwitchingEnv owning any
+  // underlying Env.
   std::unique_ptr<rocksdb::Env> memenv;
   if (dir.len == 0) {
     memenv.reset(rocksdb::NewMemEnv(rocksdb::Env::Default()));
     options.env = memenv.get();
   }
 
+  std::unique_ptr<rocksdb::Env> switching_env;
+  if (db_opts.use_switching_env) {
+    switching_env.reset(NewSwitchingEnv(options.env, options.info_log));
+    options.env = switching_env.get();
+  }
+
   rocksdb::DB *db_ptr;
   rocksdb::Status status = rocksdb::DB::Open(options, ToString(dir), &db_ptr);
   if (!status.ok()) {
     return ToDBStatus(status);
   }
   *db = new DBImpl(db_ptr, memenv.release(),
       db_opts.cache != nullptr ? db_opts.cache->rep : nullptr,
-      event_listener);
+      event_listener, switching_env.release());
   return kSuccess;
 }
 

c-deps/libroach/env_switching.cc

@@ -0,0 +1,50 @@
+// Copyright 2017 The Cockroach Authors.
+//
+// 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.
+
+#include "env_switching.h"
+
+/*
+ *
+ * SwitchingEnv switches between a base_env (usually a Env::Default or MemEnv) and an encrypted env.
+ *
+ *         -----------------------------
+ *         | SwitchingEnv (EnvWrapper) |
+ *         --- PLAIN - ENCRYPTED -------
+ *               |        \
+ *               |         \
+ *               |    ------------------------------
+ *               |    | encrypted_env (EnvWrapper) |
+ *               |    ------------------------------
+ *               |         /
+ *               |        /
+ *           ------------------
+ *           | base_env (Env) |
+ *           ------------------
+ *
+ * Any unimplemented methods are called on the base_env.
+ */
+class SwitchingEnv : public rocksdb::EnvWrapper {
+  public:
+   SwitchingEnv(rocksdb::Env* base_env, std::shared_ptr<rocksdb::Logger> logger)
+     : rocksdb::EnvWrapper(base_env),
+       logger(logger) {
+     rocksdb::Info(logger, "initialized switching env");
+   }
+  private:
+    std::shared_ptr<rocksdb::Logger> logger;
+};
+
+rocksdb::Env* NewSwitchingEnv(rocksdb::Env* base_env, std::shared_ptr<rocksdb::Logger> logger) {
+  return new SwitchingEnv(base_env ? base_env : rocksdb::Env::Default(), logger);
+}

c-deps/libroach/env_switching.h

@@ -0,0 +1,20 @@
+// Copyright 2017 The Cockroach Authors.
+//
+// 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.
+
+#pragma once
+
+#include <rocksdb/env.h>
+
+// Returns a new SwitchingEnv using the passed-in env as the base.
+rocksdb::Env* NewSwitchingEnv(rocksdb::Env* base_env, std::shared_ptr<rocksdb::Logger> logger);

c-deps/libroach/include/libroach.h

@@ -71,6 +71,7 @@ typedef struct {
   bool logging_enabled;
   int num_cpu;
   int max_open_files;
+  bool use_switching_env;
 } DBOptions;
 
 // Create a new cache with the specified size.