/* Copyright (c) 2012, 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. Without limiting anything contained in the foregoing, this file, which is part of C Driver for MySQL (Connector/C), is also subject to the Universal FOSS Exception, version 1.0, a copy of which can be found at http://oss.oracle.com/licenses/universal-foss-exception. 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 */ /** @file mysys/my_rnd.cc */ #include "my_rnd.h" #include #include #include #include "my_inttypes.h" // uint /* A wrapper to use OpenSSL PRNGs. */ void randominit(struct rand_struct *rand_st, ulong seed1, ulong seed2) { /* For mysql 3.21.# */ rand_st->max_value = 0x3FFFFFFFL; rand_st->max_value_dbl = (double)rand_st->max_value; rand_st->seed1 = seed1 % rand_st->max_value; rand_st->seed2 = seed2 % rand_st->max_value; } /** Generate random number. @param [in,out] rand_st Structure used for number generation. @retval Generated pseudo random number. */ double my_rnd(struct rand_struct *rand_st) { rand_st->seed1 = (rand_st->seed1 * 3 + rand_st->seed2) % rand_st->max_value; rand_st->seed2 = (rand_st->seed1 + rand_st->seed2 + 33) % rand_st->max_value; return (((double)rand_st->seed1) / rand_st->max_value_dbl); } /** Fill a buffer with random bytes using the SSL library routines @param [out] buffer Buffer to receive the random data @param [in] buffer_size sizeof the the buffer @retval 1 error occurred. @retval 0 OK */ int my_rand_buffer(unsigned char *buffer, size_t buffer_size) { int rc; rc = RAND_bytes(buffer, (int)buffer_size); if (!rc) { ERR_clear_error(); return 1; } return 0; } /** Generate a random number using the OpenSSL supplied random number generator if available. @param [out] failed set to TRUE if the method failed. FALSE if OK. @retval Generated random number or 0 if failed is set. */ double my_rnd_ssl(bool *failed) { unsigned int res; if (my_rand_buffer((unsigned char *)&res, sizeof(res))) { *failed = true; return 0; } else *failed = false; return (double)res / (double)UINT_MAX; }