diff options
Diffstat (limited to 'plugin/password_reuse_check')
| -rw-r--r-- | plugin/password_reuse_check/CMakeLists.txt | 3 | ||||
| -rw-r--r-- | plugin/password_reuse_check/password_reuse_check.c | 262 |
2 files changed, 265 insertions, 0 deletions
diff --git a/plugin/password_reuse_check/CMakeLists.txt b/plugin/password_reuse_check/CMakeLists.txt new file mode 100644 index 00000000..6c816071 --- /dev/null +++ b/plugin/password_reuse_check/CMakeLists.txt @@ -0,0 +1,3 @@ + +MYSQL_ADD_PLUGIN(password_reuse_check password_reuse_check.c + RECOMPILE_FOR_EMBEDDED) diff --git a/plugin/password_reuse_check/password_reuse_check.c b/plugin/password_reuse_check/password_reuse_check.c new file mode 100644 index 00000000..47c9b453 --- /dev/null +++ b/plugin/password_reuse_check/password_reuse_check.c @@ -0,0 +1,262 @@ +/* Copyright (c) 2021, Oleksandr Byelkin and MariaDB + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + 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 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 02110-1335 USA */ + +#include <my_global.h> // for int2store +#include <stdio.h> // for snprintf +#include <string.h> // for memset +#include <mysql/plugin_password_validation.h> +#include <mysqld_error.h> + +#define HISTORY_DB_NAME "password_reuse_check_history" + +#define SQL_BUFF_LEN 2048 + +#define STRING_WITH_LEN(X) (X), ((size_t) (sizeof(X) - 1)) + +// 0 - unlimited, otherwise number of days to check +static unsigned interval= 0; + +// helping string for bin_to_hex512 +static char digits[]= "0123456789ABCDEF"; + +/** + Store string with length + + @param to buffer where to put the length and string + @param from the string to store + + @return reference on the byte after copied string +*/ + +static char *store_str(char *to, const MYSQL_CONST_LEX_STRING *from) +{ + int2store(to, from->length); + memcpy(to + 2, from->str, from->length); + return to + 2 + from->length; +} + + +/** + Convert string of 512 bits (64 bytes) to hex representation + + @param to pointer to the result puffer + (should be at least 64*2 bytes) + @param str pointer to 512 bits (64 bytes string) +*/ + +static void bin_to_hex512(char *to, const unsigned char *str) +{ + const unsigned char *str_end= str + (512/8); + for (; str != str_end; ++str) + { + *to++= digits[((unsigned char) *str) >> 4]; + *to++= digits[((unsigned char) *str) & 0x0F]; + } +} + + +/** + Send SQL error as ER_UNKNOWN_ERROR for information + + @param mysql Connection handler +*/ + +static void report_sql_error(MYSQL *mysql) +{ + my_printf_error(ER_UNKNOWN_ERROR, "password_reuse_check:[%d] %s", ME_WARNING, + mysql_errno(mysql), mysql_error(mysql)); +} + + +/** + Create the history of passwords table for this plugin. + + @param mysql Connection handler + + @retval 1 - Error + @retval 0 - OK +*/ + +static int create_table(MYSQL *mysql) +{ + if (mysql_real_query(mysql, + // 512/8 = 64 + STRING_WITH_LEN("CREATE TABLE mysql." HISTORY_DB_NAME + " ( hash binary(64)," + " time timestamp not null default current_timestamp," + " primary key (hash), index tm (time) )" + " ENGINE=Aria"))) + { + report_sql_error(mysql); + return 1; + } + return 0; +} + + +/** + Run this query and create table if needed + + @param mysql Connection handler + @param query The query to run + @param len length of the query text + + @retval 1 - Error + @retval 0 - OK +*/ + +static int run_query_with_table_creation(MYSQL *mysql, const char *query, + size_t len) +{ + if (mysql_real_query(mysql, query, (unsigned long) len)) + { + unsigned int rc= mysql_errno(mysql); + if (rc != ER_NO_SUCH_TABLE) + { + if (rc != ER_DUP_ENTRY) + { + report_sql_error(mysql); + } + else + { + // warning used to do not change error code + my_printf_error(ER_NOT_VALID_PASSWORD, + "password_reuse_check: The password was already used", + ME_WARNING); + } + return 1; + } + if (create_table(mysql)) + return 1; + if (mysql_real_query(mysql, query, (unsigned long) len)) + { + report_sql_error(mysql); + return 1; + } + } + return 0; +} + + +/** + Password validator + + @param username User name (part of whole login name) + @param password Password to validate + @param hostname Host name (part of whole login name) + + @retval 1 - Password is not OK or an error happened + @retval 0 - Password is OK +*/ + +static int validate(const MYSQL_CONST_LEX_STRING *username, + const MYSQL_CONST_LEX_STRING *password, + const MYSQL_CONST_LEX_STRING *hostname) +{ + MYSQL *mysql= NULL; + size_t key_len= username->length + password->length + hostname->length + + (3 * 2 /* space for storing length of the strings */); + size_t buff_len= (key_len > SQL_BUFF_LEN ? key_len : SQL_BUFF_LEN); + size_t len; + char *buff= malloc(buff_len); + unsigned char hash[512/8]; + char escaped_hash[512/8*2 + 1]; + if (!buff) + return 1; + + mysql= mysql_init(NULL); + if (!mysql) + { + free(buff); + return 1; + } + + /* + Store: username, hostname, password + (password first to make its rewriting password in memory simplier) + */ + store_str(store_str(store_str(buff, password), username), hostname); + buff[key_len]= 0; // safety + memset(hash, 0, sizeof(hash)); + my_sha512(hash, buff, key_len); + // safety: rewrite password with zerows + memset(buff, 0, password->length); + if (mysql_real_connect_local(mysql) == NULL) + goto sql_error; + + if (interval) + { + // trim the table + len= snprintf(buff, buff_len, + "DELETE FROM mysql." HISTORY_DB_NAME + " WHERE time < DATE_SUB(NOW(), interval %d day)", + interval); + if (run_query_with_table_creation(mysql, buff, len)) + goto sql_error; + } + + bin_to_hex512(escaped_hash, hash); + escaped_hash[512/8*2]= '\0'; + len= snprintf(buff, buff_len, + "INSERT INTO mysql." HISTORY_DB_NAME "(hash) " + "values (x'%s')", + escaped_hash); + if (run_query_with_table_creation(mysql, buff, len)) + goto sql_error; + + free(buff); + mysql_close(mysql); + return 0; // OK + +sql_error: + free(buff); + if (mysql) + mysql_close(mysql); + return 1; // Error +} + +static MYSQL_SYSVAR_UINT(interval, interval, PLUGIN_VAR_RQCMDARG, + "Password history retention period in days (0 means unlimited)", NULL, NULL, + 0, 0, 365*100, 1); + + +static struct st_mysql_sys_var* sysvars[]= { + MYSQL_SYSVAR(interval), + NULL +}; + +static struct st_mariadb_password_validation info= +{ + MariaDB_PASSWORD_VALIDATION_INTERFACE_VERSION, + validate +}; + +maria_declare_plugin(password_reuse_check) +{ + MariaDB_PASSWORD_VALIDATION_PLUGIN, + &info, + "password_reuse_check", + "Oleksandr Byelkin", + "Prevent password reuse", + PLUGIN_LICENSE_GPL, + NULL, + NULL, + 0x0200, + NULL, + sysvars, + "2.0", + MariaDB_PLUGIN_MATURITY_STABLE +} +maria_declare_plugin_end; |