2023-10-10 10:31:52 -07:00

144 lines
4.1 KiB
C++

/*
* ModSecurity, http://www.modsecurity.org/
* Copyright (c) 2015 - 2023 Trustwave Holdings, Inc. (http://www.trustwave.com/)
*
* 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
*
* If any of the files related to licensing are missing or if you have any
* other questions related to licensing please contact Trustwave Holdings, Inc.
* directly using the email address security@modsecurity.org.
*
*/
#ifdef __cplusplus
#include <string>
#include <cstring>
#include <iostream>
#include <unordered_map>
#include <list>
#include <vector>
#include <algorithm>
#include <memory>
#endif
#ifdef WITH_LMDB
#include <lmdb.h>
#include <semaphore.h>
#endif // WITH_LMDB
#include <sys/stat.h>
#include <sys/types.h>
#include <fcntl.h>
#include <pthread.h>
#include "modsecurity/variable_value.h"
#include "modsecurity/collection/collection.h"
#include "src/variables/variable.h"
#ifndef SRC_COLLECTION_BACKEND_LMDB_H_
#define SRC_COLLECTION_BACKEND_LMDB_H_
#ifdef WITH_LMDB
#ifdef __cplusplus
namespace modsecurity {
namespace collection {
namespace backend {
/**
* The MDBEnvProvider class defines the `GetInstance` method that serves as an
* alternative to constructor and lets clients access the same instance of this
* class over and over. Its used to provide single MDB_env instance for each collection
* that uses lmdb to store and retrieve data. That approach satisfies lmdb requirement:
*
* "LMDB uses POSIX locks on files, and these locks have issues if one process opens
* a file multiple times. Because of this, do not mdb_env_open() a file multiple
* times from a single process."
*
* Creation of MDB_env is delayed to moment when first transaction is opened.
* This approach prevents passing env object to forked processes.
* In that way next lmdb requirement be satisfied:
*
* "Use an MDB_env* in the process which opened it, without fork()ing."
*/
class MDBEnvProvider {
public:
MDBEnvProvider(MDBEnvProvider &other) = delete;
void operator=(const MDBEnvProvider &) = delete;
/**
* This is the static method that controls the access to the singleton
* instance. On the first run, it creates a singleton object and places it
* into the static field. On subsequent runs, it returns the client existing
* object stored in the static field (Meyers Singleton implementation).
*/
static MDBEnvProvider& GetInstance() {
static MDBEnvProvider instance;
return instance;
}
MDB_env* GetEnv();
MDB_dbi* GetDBI();
bool isValid();
~MDBEnvProvider();
private:
MDB_env *m_env;
MDB_dbi m_dbi;
bool valid;
MDBEnvProvider();
};
class LMDB :
public Collection {
public:
explicit LMDB(const std::string &name);
void store(std::string key, std::string value) override;
bool storeOrUpdateFirst(const std::string &key,
const std::string &value) override;
bool updateFirst(const std::string &key,
const std::string &value) override;
void del(const std::string& key) override;
void setExpiry(const std::string& key, int32_t expiry_seconds) override;
std::unique_ptr<std::string> resolveFirst(const std::string& var) override;
void resolveSingleMatch(const std::string& var,
std::vector<const VariableValue *> *l) override;
void resolveMultiMatches(const std::string& var,
std::vector<const VariableValue *> *l,
variables::KeyExclusions &ke) override;
void resolveRegularExpression(const std::string& var,
std::vector<const VariableValue *> *l,
variables::KeyExclusions &ke) override;
private:
int txn_begin(unsigned int flags, MDB_txn **ret);
void string2val(const std::string& str, MDB_val *val);
void inline lmdb_debug(int rc, const std::string &op, const std::string &scope);
void delIfExpired(const std::string& key);
MDB_env *m_env;
MDB_dbi m_dbi;
bool isOpen;
};
} // namespace backend
} // namespace collection
} // namespace modsecurity
#endif
#endif // WITH_LMDB
#endif // SRC_COLLECTION_BACKEND_LMDB_H_