Adding upstream version 2.2.0.upstream/2.2.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 521 insertions, 0 deletions

diff --git a/src/lib/mysql/mysql_connection.cc b/src/lib/mysql/mysql_connection.cc
new file mode 100644
index 0000000..fc65cce
--- /dev/null
+++ b/src/lib/mysql/mysql_connection.cc
@@ -0,0 +1,521 @@
+// Copyright (C) 2012-2022 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#include <config.h>
+
+#include <database/db_log.h>
+#include <exceptions/exceptions.h>
+#include <mysql/mysql_connection.h>
+#include <util/file_utilities.h>
+
+#include <boost/lexical_cast.hpp>
+
+#include <algorithm>
+#include <stdint.h>
+#include <string>
+#include <limits>
+
+using namespace isc;
+using namespace std;
+
+namespace isc {
+namespace db {
+
+int MySqlHolder::atexit_ = [] {
+    return atexit([] { mysql_library_end(); });
+}();
+
+/// @todo: Migrate this default value to src/bin/dhcpX/simple_parserX.cc
+const int MYSQL_DEFAULT_CONNECTION_TIMEOUT = 5; // seconds
+
+MySqlTransaction::MySqlTransaction(MySqlConnection& conn)
+    : conn_(conn), committed_(false) {
+    conn_.startTransaction();
+}
+
+MySqlTransaction::~MySqlTransaction() {
+    // Rollback if the MySqlTransaction::commit wasn't explicitly
+    // called.
+    if (!committed_) {
+        conn_.rollback();
+    }
+}
+
+void
+MySqlTransaction::commit() {
+    conn_.commit();
+    committed_ = true;
+}
+
+// Open the database using the parameters passed to the constructor.
+
+void
+MySqlConnection::openDatabase() {
+    // Set up the values of the parameters
+    const char* host = "localhost";
+    string shost;
+    try {
+        shost = getParameter("host");
+        host = shost.c_str();
+    } catch (...) {
+        // No host.  Fine, we'll use "localhost"
+    }
+
+    unsigned int port = 0;
+    string sport;
+    try {
+        sport = getParameter("port");
+    } catch (...) {
+        // No port parameter, we are going to use the default port.
+        sport = "";
+    }
+
+    if (sport.size() > 0) {
+        // Port was given, so try to convert it to an integer.
+
+        try {
+            port = boost::lexical_cast<unsigned int>(sport);
+        } catch (...) {
+            // Port given but could not be converted to an unsigned int.
+            // Just fall back to the default value.
+            port = 0;
+        }
+
+        // The port is only valid when it is in the 0..65535 range.
+        // Again fall back to the default when the given value is invalid.
+        if (port > numeric_limits<uint16_t>::max()) {
+            port = 0;
+        }
+    }
+
+    const char* user = NULL;
+    string suser;
+    try {
+        suser = getParameter("user");
+        user = suser.c_str();
+    } catch (...) {
+        // No user.  Fine, we'll use NULL
+    }
+
+    const char* password = NULL;
+    string spassword;
+    try {
+        spassword = getParameter("password");
+        password = spassword.c_str();
+    } catch (...) {
+        // No password.  Fine, we'll use NULL
+    }
+
+    const char* name = NULL;
+    string sname;
+    try {
+        sname = getParameter("name");
+        name = sname.c_str();
+    } catch (...) {
+        // No database name.  Throw a "NoName" exception
+        isc_throw(NoDatabaseName, "must specify a name for the database");
+    }
+
+    unsigned int connect_timeout = MYSQL_DEFAULT_CONNECTION_TIMEOUT;
+    string stimeout;
+    try {
+        stimeout = getParameter("connect-timeout");
+    } catch (...) {
+        // No timeout parameter, we are going to use the default timeout.
+        stimeout = "";
+    }
+
+    if (stimeout.size() > 0) {
+        // Timeout was given, so try to convert it to an integer.
+
+        try {
+            connect_timeout = boost::lexical_cast<unsigned int>(stimeout);
+        } catch (...) {
+            // Timeout given but could not be converted to an unsigned int. Set
+            // the connection timeout to an invalid value to trigger throwing
+            // of an exception.
+            connect_timeout = 0;
+        }
+
+        // The timeout is only valid if greater than zero, as depending on the
+        // database, a zero timeout might signify something like "wait
+        // indefinitely".
+        //
+        // The check below also rejects a value greater than the maximum
+        // integer value.  The lexical_cast operation used to obtain a numeric
+        // value from a string can get confused if trying to convert a negative
+        // integer to an unsigned int: instead of throwing an exception, it may
+        // produce a large positive value.
+        if ((connect_timeout == 0) ||
+            (connect_timeout > numeric_limits<int>::max())) {
+            isc_throw(DbInvalidTimeout, "database connection timeout (" <<
+                      stimeout << ") must be an integer greater than 0");
+        }
+    }
+
+    const char* ca_file(0);
+    const char* ca_dir(0);
+    string sca;
+    try {
+        sca = getParameter("trust-anchor");
+        tls_ = true;
+        if (util::file::isDir(sca)) {
+            ca_dir = sca.c_str();
+        } else {
+            ca_file = sca.c_str();
+        }
+    } catch (...) {
+        // No trust anchor
+    }
+
+    const char* cert_file(0);
+    string scert;
+    try {
+        scert = getParameter("cert-file");
+        tls_ = true;
+        cert_file = scert.c_str();
+    } catch (...) {
+        // No client certificate file
+    }
+
+    const char* key_file(0);
+    string skey;
+    try {
+        skey = getParameter("key-file");
+        tls_ = true;
+        key_file = skey.c_str();
+    } catch (...) {
+        // No private key file
+    }
+
+    const char* cipher_list(0);
+    string scipher;
+    try {
+        scipher = getParameter("cipher-list");
+        tls_ = true;
+        cipher_list = scipher.c_str();
+    } catch (...) {
+        // No cipher list
+    }
+
+    // Set options for the connection:
+    //
+    // Set options for the connection:
+    // Make sure auto_reconnect is OFF! Enabling it leaves us with an unusable
+    // connection after a reconnect as among other things, it drops all our
+    // pre-compiled statements.
+    my_bool auto_reconnect = MLM_FALSE;
+    int result = mysql_options(mysql_, MYSQL_OPT_RECONNECT, &auto_reconnect);
+    if (result != 0) {
+        isc_throw(DbOpenError, "unable to set auto-reconnect option: " <<
+                  mysql_error(mysql_));
+    }
+
+    // Make sure we have a large idle time window ... say 30 days...
+    const char *wait_time = "SET SESSION wait_timeout = 30 * 86400";
+    result = mysql_options(mysql_, MYSQL_INIT_COMMAND, wait_time);
+    if (result != 0) {
+        isc_throw(DbOpenError, "unable to set wait_timeout " <<
+                  mysql_error(mysql_));
+    }
+
+    // Set SQL mode options for the connection:  SQL mode governs how what
+    // constitutes insertable data for a given column, and how to handle
+    // invalid data.  We want to ensure we get the strictest behavior and
+    // to reject invalid data with an error.
+    const char *sql_mode = "SET SESSION sql_mode ='STRICT_ALL_TABLES'";
+    result = mysql_options(mysql_, MYSQL_INIT_COMMAND, sql_mode);
+    if (result != 0) {
+        isc_throw(DbOpenError, "unable to set SQL mode options: " <<
+                  mysql_error(mysql_));
+    }
+
+    // Connection timeout, the amount of time taken for the client to drop
+    // the connection if the server is not responding.
+    result = mysql_options(mysql_, MYSQL_OPT_CONNECT_TIMEOUT, &connect_timeout);
+    if (result != 0) {
+        isc_throw(DbOpenError, "unable to set database connection timeout: " <<
+                  mysql_error(mysql_));
+    }
+
+    // If TLS is enabled set it. If something should go wrong it will happen
+    // later at the mysql_real_connect call.
+    if (tls_) {
+        mysql_ssl_set(mysql_, key_file, cert_file, ca_file, ca_dir,
+                      cipher_list);
+    }
+
+    // Open the database.
+    //
+    // The option CLIENT_FOUND_ROWS is specified so that in an UPDATE,
+    // the affected rows are the number of rows found that match the
+    // WHERE clause of the SQL statement, not the rows changed.  The reason
+    // here is that MySQL apparently does not update a row if data has not
+    // changed and so the "affected rows" (retrievable from MySQL) is zero.
+    // This makes it hard to distinguish whether the UPDATE changed no rows
+    // because no row matching the WHERE clause was found, or because a
+    // row was found but no data was altered.
+    MYSQL* status = mysql_real_connect(mysql_, host, user, password, name,
+                                       port, NULL, CLIENT_FOUND_ROWS);
+    if (status != mysql_) {
+        isc_throw(DbOpenError, mysql_error(mysql_));
+    }
+
+    // Enable autocommit. In case transaction is explicitly used, this
+    // setting will be overwritten for the transaction. However, there are
+    // cases when lack of autocommit could cause transactions to hang
+    // until commit or rollback is explicitly called. This already
+    // caused issues for some unit tests which were unable to cleanup
+    // the database after the test because of pending transactions.
+    // Use of autocommit will eliminate this problem.
+    my_bool autocommit_result = mysql_autocommit(mysql_, 1);
+    if (autocommit_result != 0) {
+        isc_throw(DbOperationError, mysql_error(mysql_));
+    }
+
+    // To avoid a flush to disk on every commit, the global parameter
+    // innodb_flush_log_at_trx_commit should be set to 2. This will cause the
+    // changes to be written to the log, but flushed to disk in the background
+    // every second. Setting the parameter to that value will speed up the
+    // system, but at the risk of losing data if the system crashes.
+}
+
+// Get schema version.
+
+std::pair<uint32_t, uint32_t>
+MySqlConnection::getVersion(const ParameterMap& parameters) {
+    // Get a connection.
+    MySqlConnection conn(parameters);
+
+    // Open the database.
+    conn.openDatabase();
+
+    // Allocate a new statement.
+    MYSQL_STMT *stmt = mysql_stmt_init(conn.mysql_);
+    if (stmt == NULL) {
+        isc_throw(DbOperationError, "unable to allocate MySQL prepared "
+                "statement structure, reason: " << mysql_error(conn.mysql_));
+    }
+
+    try {
+
+        // Prepare the statement from SQL text.
+        const char* version_sql = "SELECT version, minor FROM schema_version";
+        int status = mysql_stmt_prepare(stmt, version_sql, strlen(version_sql));
+        if (status != 0) {
+            isc_throw(DbOperationError, "unable to prepare MySQL statement <"
+                      << version_sql << ">, reason: "
+                      << mysql_error(conn.mysql_));
+        }
+
+        // Execute the prepared statement.
+        if (MysqlExecuteStatement(stmt) != 0) {
+            isc_throw(DbOperationError, "cannot execute schema version query <"
+                      << version_sql << ">, reason: "
+                      << mysql_errno(conn.mysql_));
+        }
+
+        // Bind the output of the statement to the appropriate variables.
+        MYSQL_BIND bind[2];
+        memset(bind, 0, sizeof(bind));
+
+        uint32_t version;
+        bind[0].buffer_type = MYSQL_TYPE_LONG;
+        bind[0].is_unsigned = 1;
+        bind[0].buffer = &version;
+        bind[0].buffer_length = sizeof(version);
+
+        uint32_t minor;
+        bind[1].buffer_type = MYSQL_TYPE_LONG;
+        bind[1].is_unsigned = 1;
+        bind[1].buffer = &minor;
+        bind[1].buffer_length = sizeof(minor);
+
+        if (mysql_stmt_bind_result(stmt, bind)) {
+            isc_throw(DbOperationError, "unable to bind result set for <"
+                      << version_sql << ">, reason: "
+                      << mysql_errno(conn.mysql_));
+        }
+
+        // Fetch the data.
+        if (mysql_stmt_fetch(stmt)) {
+            isc_throw(DbOperationError, "unable to bind result set for <"
+                      << version_sql << ">, reason: "
+                      << mysql_errno(conn.mysql_));
+        }
+
+        // Discard the statement and its resources
+        mysql_stmt_close(stmt);
+
+        return (std::make_pair(version, minor));
+
+    } catch (const std::exception&) {
+        // Avoid a memory leak on error.
+        mysql_stmt_close(stmt);
+
+        // Send the exception to the caller.
+        throw;
+    }
+}
+
+// Prepared statement setup.  The textual form of an SQL statement is stored
+// in a vector of strings (text_statements_) and is used in the output of
+// error messages.  The SQL statement is also compiled into a "prepared
+// statement" (stored in statements_), which avoids the overhead of compilation
+// during use.  As prepared statements have resources allocated to them, the
+// class destructor explicitly destroys them.
+
+void
+MySqlConnection::prepareStatement(uint32_t index, const char* text) {
+    // Validate that there is space for the statement in the statements array
+    // and that nothing has been placed there before.
+    if ((index >= statements_.size()) || (statements_[index] != NULL)) {
+        isc_throw(InvalidParameter, "invalid prepared statement index (" <<
+                  static_cast<int>(index) << ") or indexed prepared " <<
+                  "statement is not null");
+    }
+
+    // All OK, so prepare the statement
+    text_statements_[index] = std::string(text);
+    statements_[index] = mysql_stmt_init(mysql_);
+    if (statements_[index] == NULL) {
+        isc_throw(DbOperationError, "unable to allocate MySQL prepared "
+                  "statement structure, reason: " << mysql_error(mysql_));
+    }
+
+    int status = mysql_stmt_prepare(statements_[index], text, strlen(text));
+    if (status != 0) {
+        isc_throw(DbOperationError, "unable to prepare MySQL statement <" <<
+                  text << ">, reason: " << mysql_error(mysql_));
+    }
+}
+
+void
+MySqlConnection::prepareStatements(const TaggedStatement* start_statement,
+                                   const TaggedStatement* end_statement) {
+    // Created the MySQL prepared statements for each DML statement.
+    for (const TaggedStatement* tagged_statement = start_statement;
+         tagged_statement != end_statement; ++tagged_statement) {
+        if (tagged_statement->index >= statements_.size()) {
+            statements_.resize(tagged_statement->index + 1, NULL);
+            text_statements_.resize(tagged_statement->index + 1,
+                                    std::string(""));
+        }
+        prepareStatement(tagged_statement->index,
+                         tagged_statement->text);
+    }
+}
+
+void MySqlConnection::clearStatements() {
+    statements_.clear();
+    text_statements_.clear();
+}
+
+/// @brief Destructor
+MySqlConnection::~MySqlConnection() {
+    // Free up the prepared statements, ignoring errors. (What would we do
+    // about them? We're destroying this object and are not really concerned
+    // with errors on a database connection that is about to go away.)
+    for (int i = 0; i < statements_.size(); ++i) {
+        if (statements_[i] != NULL) {
+            (void) mysql_stmt_close(statements_[i]);
+            statements_[i] = NULL;
+        }
+    }
+    statements_.clear();
+    text_statements_.clear();
+}
+
+// Time conversion methods.
+//
+// Note that the MySQL TIMESTAMP data type (used for "expire") converts data
+// from the current timezone to UTC for storage, and from UTC to the current
+// timezone for retrieval.
+//
+// This causes no problems providing that:
+// a) cltt is given in local time
+// b) We let the system take care of timezone conversion when converting
+//    from a time read from the database into a local time.
+void
+MySqlConnection::convertToDatabaseTime(const time_t input_time,
+                                       MYSQL_TIME& output_time) {
+    MySqlBinding::convertToDatabaseTime(input_time, output_time);
+}
+
+void
+MySqlConnection::convertToDatabaseTime(const time_t cltt,
+                                       const uint32_t valid_lifetime,
+                                       MYSQL_TIME& expire) {
+    MySqlBinding::convertToDatabaseTime(cltt, valid_lifetime, expire);
+}
+
+void
+MySqlConnection::convertFromDatabaseTime(const MYSQL_TIME& expire,
+                                         uint32_t valid_lifetime, time_t& cltt) {
+    MySqlBinding::convertFromDatabaseTime(expire, valid_lifetime, cltt);
+}
+
+void
+MySqlConnection::startTransaction() {
+    // If it is nested transaction, do nothing.
+    if (++transaction_ref_count_ > 1) {
+        return;
+    }
+
+    DB_LOG_DEBUG(DB_DBG_TRACE_DETAIL, MYSQL_START_TRANSACTION);
+    checkUnusable();
+    // We create prepared statements for all other queries, but MySQL
+    // don't support prepared statements for START TRANSACTION.
+    int status = mysql_query(mysql_, "START TRANSACTION");
+    if (status != 0) {
+        isc_throw(DbOperationError, "unable to start transaction, "
+                  "reason: " << mysql_error(mysql_));
+    }
+}
+
+bool
+MySqlConnection::isTransactionStarted() const {
+    return (transaction_ref_count_ > 0);
+}
+
+void
+MySqlConnection::commit() {
+    if (transaction_ref_count_ <= 0) {
+        isc_throw(Unexpected, "commit called for not started transaction - coding error");
+    }
+
+    // When committing nested transaction, do nothing.
+    if (--transaction_ref_count_ > 0) {
+        return;
+    }
+    DB_LOG_DEBUG(DB_DBG_TRACE_DETAIL, MYSQL_COMMIT);
+    checkUnusable();
+    if (mysql_commit(mysql_) != 0) {
+        isc_throw(DbOperationError, "commit failed: "
+                  << mysql_error(mysql_));
+    }
+}
+
+void
+MySqlConnection::rollback() {
+    if (transaction_ref_count_ <= 0) {
+        isc_throw(Unexpected, "rollback called for not started transaction - coding error");
+    }
+
+    // When rolling back nested transaction, do nothing.
+    if (--transaction_ref_count_ > 0) {
+        return;
+    }
+    DB_LOG_DEBUG(DB_DBG_TRACE_DETAIL, MYSQL_ROLLBACK);
+    checkUnusable();
+    if (mysql_rollback(mysql_) != 0) {
+        isc_throw(DbOperationError, "rollback failed: "
+                  << mysql_error(mysql_));
+    }
+}
+
+} // namespace db
+} // namespace isc