mysql-server/sql/server_component/mysql_connection_attributes_iterator_imp.cc
2025-03-05 14:31:37 +07:00

128 lines
4.8 KiB
C++

/* Copyright (c) 2019, 2024, Oracle and/or its affiliates.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License, version 2.0,
as published by the Free Software Foundation.
This program is designed to work with certain software (including
but not limited to OpenSSL) that is licensed under separate terms,
as designated in a particular file or component or in included license
documentation. The authors of MySQL hereby grant you an additional
permission to link the program and your derivative works with the
separately licensed software that they have either included with
the program or referenced in the documentation.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License, version 2.0, for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
#include "mysql_connection_attributes_iterator_imp.h"
#include <sql/sql_class.h>
DEFINE_BOOL_METHOD(mysql_connection_attributes_iterator_imp::init,
(MYSQL_THD opaque_thd,
my_h_connection_attributes_iterator *iterator)) {
try {
THD *thd;
if (opaque_thd != nullptr)
thd = reinterpret_cast<THD *>(opaque_thd);
else
thd = current_thd;
if (iterator != nullptr && thd->m_connection_attributes.size() > 0) {
*iterator = thd->m_connection_attributes.data();
return false; // Success
} else
return true; /* invalid option */
} catch (...) {
return true;
}
}
DEFINE_BOOL_METHOD(mysql_connection_attributes_iterator_imp::deinit,
(my_h_connection_attributes_iterator iterator)) {
if (iterator != nullptr) {
// nothing to do
return false; // Success
} else
return true; /* invalid option */
}
/**
Helper function to decode lenght-encoded string and advance to the next
length-encoded part.
*/
std::tuple<const char *, size_t, bool> parse_length_encoded_string(
const char **str, std::vector<char> *connection_attributes_vector) {
size_t length;
const char *result;
const auto &connection_attributes = connection_attributes_vector->data();
size_t connection_attributes_length = connection_attributes_vector->size();
// check if we're in the connection attributes string boundaries
if (*str < connection_attributes || *str > connection_attributes +
connection_attributes_length -
sizeof(char))
return std::make_tuple(nullptr, 0, false);
// The first item of the string is the length of the attribute
length = **str;
result = *str + 1;
/* Check if we're still in the connection attributes string boundaries.
Note: the original condition was:
if (*str + length > connection_attributes + connection_attributes_length)
but it lead to pointer overflow. Now it cannot overflow.
Note2: 5 lines above we make sure *str > connection_attributes
*/
if (length > connection_attributes_length ||
static_cast<size_t>(*str - connection_attributes) >
connection_attributes_length - length)
return std::make_tuple(nullptr, 0, false);
// Advance the iterator with the parsed string length, plus the extra
// length byte
*str += length + 1;
return std::make_tuple(result, length, true);
}
DEFINE_BOOL_METHOD(mysql_connection_attributes_iterator_imp::get,
(MYSQL_THD opaque_thd,
my_h_connection_attributes_iterator *iterator,
const char **name, size_t *name_length, const char **value,
size_t *value_length, const char **client_charset)) {
try {
THD *thd;
if (opaque_thd != nullptr)
thd = reinterpret_cast<THD *>(opaque_thd);
else
thd = current_thd;
if (name != nullptr && name_length != nullptr && value != nullptr &&
value_length != nullptr && iterator != nullptr) {
bool isParsingSuccessful;
std::tie(*name, *name_length, isParsingSuccessful) =
parse_length_encoded_string(iterator, &thd->m_connection_attributes);
if (!isParsingSuccessful) return true;
std::tie(*value, *value_length, isParsingSuccessful) =
parse_length_encoded_string(iterator, &thd->m_connection_attributes);
if (!isParsingSuccessful) return true;
*client_charset = thd->variables.character_set_client->m_coll_name;
return false; // Success
} else
return true; /* invalid option */
} catch (...) {
return true;
}
}