1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 * 25 * Copyright 2017 Nexenta Systems, Inc. All rights reserved. 26 */ 27 28 #ifndef _NS_CONNMGMT_H 29 #define _NS_CONNMGMT_H 30 31 #ifdef __cplusplus 32 extern "C" { 33 #endif 34 35 #include <thread.h> 36 #include "ns_sldap.h" 37 #include "ns_internal.h" 38 #include "ns_cache_door.h" 39 40 struct ns_conn_user; /* connection user, forward definition */ 41 struct ns_conn_mt; /* multi-threaded (MT) connection, forward definition */ 42 struct ns_conn_mgmt; /* connection management, forward definition */ 43 44 #define NS_CONN_MT_USER_NO_MAX -1 45 #define NS_CONN_MT_USER_MAX NS_CONN_MT_USER_NO_MAX 46 #define NS_LIST_TRY_MAX 3 47 48 /* 49 * Structure for handling the waiter of a pending multi-threaded (MT) connection 50 */ 51 typedef struct ns_conn_waiter { 52 cond_t waitcv; 53 uint8_t signaled; 54 struct ns_conn_user *key; 55 struct ns_conn_waiter *next, *prev; 56 } ns_conn_waiter_t; 57 58 /* 59 * type of a connection user 60 */ 61 typedef enum { 62 NS_CONN_USER_SEARCH = 1, 63 NS_CONN_USER_WRITE = 2, 64 NS_CONN_USER_AUTH = 3, 65 NS_CONN_USER_GETENT = 4 66 } ns_conn_user_type_t; 67 68 /* 69 * state of a connection user 70 */ 71 typedef enum { 72 NS_CONN_USER_UNINITED = 0, 73 NS_CONN_USER_ALLOCATED = 1, 74 NS_CONN_USER_FINDING = 2, /* looking for an MT connection */ 75 NS_CONN_USER_WAITING = 3, /* waiting for an MT connection */ 76 NS_CONN_USER_WOKEUP = 4, 77 NS_CONN_USER_CONNECT_ERROR = 5, 78 NS_CONN_USER_CONNECTED = 6, 79 NS_CONN_USER_DISCONNECTED = 7, 80 NS_CONN_USER_FREED = 8 81 } ns_conn_user_state_t; 82 83 /* 84 * A connection user represents a request processed by libsldap. It 85 * usually is a thread using the same connection from start to end. 86 * Different connection users of the same type can share the same 87 * connection opened for that type. But search and getent users can 88 * share the same connection opened for either search or getent. AUTH 89 * connection are not shareable. 90 * 91 * A getent user may have a longer lifespan and live outside of libsldap. 92 * This is because the associated search cookie is passed back to the caller 93 * via the firstEntry call and used in the subsequent nextEntry or endEntry 94 * calls. Even though the firstEntry and the nextEntry/endEntry calls may 95 * be running in a different thread, the connection being used will be the 96 * same. It is the one assigend during the firstEntry call. 97 */ 98 struct ns_conn_user { 99 ns_conn_user_type_t type; /* search, write, auth, getent, ... */ 100 ns_conn_user_state_t state; 101 thread_t tid; /* id of the thread starts the request */ 102 struct ns_conn_user *next; /* next conn_user in the linked list */ 103 struct ns_conn_mt *conn_mt; /* the MT connection being used */ 104 struct ns_conn_mgmt *conn_mgmt; /* ref counted conn management */ 105 void *userinfo; /* private data of the request */ 106 ns_ldap_return_code ns_rc; /* error return code */ 107 ns_ldap_error_t *ns_error; /* error info */ 108 boolean_t referral; /* using a referred server ? */ 109 boolean_t retry; /* retry the request on certain error? */ 110 boolean_t keep_conn; /* keep the conn for reuse ? */ 111 boolean_t use_mt_conn; /* using/used an MT connection ? */ 112 boolean_t bad_mt_conn; /* MT connection is not usable ? */ 113 }; 114 115 /* 116 * state of an MT connection 117 */ 118 typedef enum { 119 NS_CONN_MT_UNINITED = 0, 120 NS_CONN_MT_CONNECTING = 1, 121 NS_CONN_MT_CONNECT_ERROR = 2, 122 NS_CONN_MT_CONNECTED = 3, 123 NS_CONN_MT_CLOSING = 4 124 } ns_conn_mt_state_t; 125 126 /* 127 * An ns_conn_mt (or MT connection) represents an ldap connection 128 * that can be shared among multiple threads. It also represents 129 * the set of connection users using the ldap connection. It contains 130 * a pointer to the Connection structure that has the physical info 131 * of the connection (server name, address, ldap handle, etc). It 132 * also contains a linked list of all the conn_user using the ldap 133 * connection. The connection users can wait on an MT connection 134 * to become available or be told to abort and clean up when one of 135 * the connection user detects an error and knows that the connection 136 * is no longer usable. The error info is then saved in the structure 137 * for other users to consume. 138 * 139 * An MT connection is meant to be shared concurrently and persistent. 140 * Even when there's no current user, it will be kept by the connection 141 * management, waiting for the next user. It will be closed when 142 * a connection error is detected, when a better server should be 143 * used, when the Native LDAP configuration change, or when the libsldap 144 * is being unloaded. 145 */ 146 typedef struct ns_conn_mt { 147 mutex_t lock; 148 ns_conn_mt_state_t state; 149 pid_t pid; /* process creates the connection */ 150 thread_t tid; /* thread creates the connection */ 151 struct ns_conn_mt *next; /* next conn_mt in the linked list */ 152 ns_conn_user_t *cu_head; /* head of conn_user linked list */ 153 ns_conn_user_t *cu_tail; /* tail of conn_user linked list */ 154 struct ns_conn_mgmt *conn_mgmt; /* ref counted conn management */ 155 ns_conn_waiter_t waiter; /* first of the connection waiters */ 156 uint_t cu_cnt; /* number of the using conn_user */ 157 int32_t cu_max; /* max. allowed number of conn_user */ 158 uint_t waiter_cnt; /* number of waiters */ 159 ns_conn_user_type_t opened_for; /* type of conn_user opened for */ 160 Connection *conn; /* name, IP address, ldap handle, etc */ 161 time_t create_time; /* time when connection created */ 162 time_t access_time; /* time when last used */ 163 ns_ldap_return_code ns_rc; /* saved error code */ 164 ns_ldap_error_t *ns_error; /* saved error info */ 165 boolean_t close_when_nouser; /* close connection when */ 166 /* last user is done ? */ 167 boolean_t detached; /* no longer in connection pool? */ 168 boolean_t referral; /* using a referred server ? */ 169 } ns_conn_mt_t; 170 171 /* 172 * state of a connection management 173 * (a connection pool sharing the same native LDAP configuration) 174 */ 175 typedef enum { 176 NS_CONN_MGMT_UNINITED = 0, 177 NS_CONN_MGMT_INACTIVE = 1, /* conn sharing not yet requested */ 178 NS_CONN_MGMT_ACTIVE = 2, /* connection sharing required/requested */ 179 NS_CONN_MGMT_DETACHED = 3 /* on the way down, no new user allowed */ 180 } ns_conn_mgmt_state_t; 181 182 /* 183 * An ns_conn_mgmt (or connection management) represents the set of MT 184 * connections using the same native LDAP configuration. It is a connection 185 * pool that can adjust the MT connection status and usage based on the 186 * change notifications it receives from the ldap_cachemgr daemon, OR When 187 * the change is detected at config refresh time. When a server status 188 * change (up or down) notification is received or detected, it will 189 * close the MT connections using the server. Or mark them as to-be-closed 190 * and close them when all users are done using them. When a config change 191 * notice is received, it will detach itself and allow a new ns_conn_mgmt be 192 * created for the new configuration. The old config would still be used 193 * by the detached ns_conn_mgmt. Both will be destroyed when all existing 194 * conn_user are done. Any conn_user and MT connection created after the 195 * configuration switch will use the new configuration. 196 * 197 * Note that there's always just one current ns_conn_mgmt. Its usage is 198 * reference counted. Any new conn_user or MT connection referencing 199 * the ns_conn_mgmt adds 1 to the count, any release of the ns_conn_mgmt 200 * decrement the count by 1. The ns_conn_mgmt can not be freed until 201 * the reference count becomes zero. 202 * 203 * Each ns_conn_mgmt references a native LDAP configuration. The config 204 * component of this library always maintains a global configuration. It is 205 * referred to as the current global config. The current ns_conn_mgmt 206 * uses that global config. When an ns_conn_mgmt is detached, or not 207 * longer active/current, the config it uses is no longer the current global 208 * one, which is referred as the per connection management config. When 209 * the ns_conn_mgmt is freed, the config will also be destroyed. 210 */ 211 212 typedef struct ns_conn_mgmt { 213 mutex_t lock; 214 ns_conn_mgmt_state_t state; 215 pid_t pid; /* process creates the conn_mgmt */ 216 thread_t procchg_tid; /* id of the change monitor thread */ 217 ns_conn_mt_t *cm_head; /* head of the conn_mt linked list */ 218 ns_conn_mt_t *cm_tail; /* tail of the conn_mt linked list */ 219 mutex_t cfg_lock; /* lock serializes access to config */ 220 ldap_get_chg_cookie_t cfg_cookie; /* used to detect if config changes */ 221 ns_config_t *config; /* the native LDAP config being used */ 222 char **pservers; /* preferred servers defined in config */ 223 uint_t cm_cnt; /* number of MT connection in the pool */ 224 uint_t ref_cnt; /* number of reference by conn_MT/conn_user */ 225 boolean_t is_nscd; /* running in a nscd ? */ 226 boolean_t is_peruser_nscd; /* running in a per-user nscd ? */ 227 boolean_t ldap_mt; /* libldap supports multi-threaded client ? */ 228 boolean_t do_mt_conn; /* need and able to do MT conn ? */ 229 boolean_t shutting_down; /* on the way down ? */ 230 boolean_t cfg_reloaded; /* config is not current ? */ 231 boolean_t procchg_started; /* change monitor thread started ? */ 232 boolean_t procchg_door_call; /* in door call and waiting ? */ 233 boolean_t pservers_loaded; /* pservers array is set ? */ 234 } ns_conn_mgmt_t; 235 236 /* 237 * For a connection management and the conn_mt connections it manages, it is 238 * very helpful to know exactly when the Native LDAP configuration changes 239 * and when the status of the configured servers change. If the config 240 * changes, new connection management will be created. If servers go up 241 * or down, conn_mt connections being used need to be dropped or switched. 242 * For processes other than the main nscd, the changes has to be detected 243 * in a less efficient way by libsldap. For the main nscd (not including 244 * peruser nscd), the connection management which has active conn_mt 245 * connections can rely on the ldap_cachemgr daemon to report if there's any 246 * change in servers' status or if the native LDAP configuration has changed. 247 * 248 * The mechanism for reporting of the changes is a door call sent from 249 * libsldap to ldap_cachemgr. The call will not be returned until changes 250 * detected by ldap_cachemgr. When the change info is passed back to 251 * libsldap, the change monitor thread will wake up from the door call 252 * and process the notification. For servers went from up to down, the 253 * associated MT connections will be closed, and then all conn_users' 254 * state will be marked as closing. When a conn_user notices it, the 255 * operations represented by that conn_user will be ended with error 256 * info. When a more preferred server is up, MT connections using 257 * less preferred servers will be marked as closed-when-all-user-done, 258 * so that new connection will be opened and using the preferred server. 259 * A configuration change causes the current connection management and 260 * the configuration it uses to become detached but continually being 261 * used by the old MT connections. Any new MT connection opened will 262 * be put in a new connection management and uses the new configuration 263 * immediately. 264 */ 265 typedef enum { 266 NS_SERVER_UP = 1, 267 NS_SERVER_DOWN = 2 268 } ns_server_status_t; 269 270 typedef struct ns_server_status_change { 271 int num_server; 272 boolean_t config_changed; 273 ns_server_status_t *changes; /* array of status change */ 274 char **servers; /* array of server */ 275 } ns_server_status_change_t; 276 277 /* 278 * connection management functions 279 */ 280 ns_conn_mgmt_t *__s_api_conn_mgmt_init(); 281 int __s_api_setup_mt_ld(LDAP *ld); 282 int __s_api_check_mtckey(); 283 void __s_api_use_prev_conn_mgmt(int, ns_config_t *); 284 ns_conn_user_t *__s_api_conn_user_init(int, void *, boolean_t); 285 void __s_api_conn_mt_return(ns_conn_user_t *); 286 void __s_api_conn_user_free(ns_conn_user_t *); 287 int __s_api_conn_mt_add(Connection *con, ns_conn_user_t *, ns_ldap_error_t **); 288 int __s_api_conn_mt_get(const char *, const int, const ns_cred_t *, 289 Connection **, ns_ldap_error_t **, ns_conn_user_t *); 290 void __s_api_conn_mt_remove(ns_conn_user_t *, int, ns_ldap_error_t **); 291 int __s_api_check_libldap_MT_conn_support(ns_conn_user_t *, LDAP *ld, 292 ns_ldap_error_t **); 293 void __s_api_conn_mt_close(ns_conn_user_t *, int, ns_ldap_error_t **); 294 void __s_api_reinit_conn_mgmt_new_config(ns_config_t *); 295 int __s_api_setup_retry_search(ns_conn_user_t **, ns_conn_user_type_t, int *, 296 int *, ns_ldap_error_t **); 297 int __s_api_setup_getnext(ns_conn_user_t *, int *, ns_ldap_error_t **); 298 void __s_api_shutdown_conn_mgmt(); 299 300 #ifdef __cplusplus 301 } 302 #endif 303 304 #endif /* _NS_CONNMGMT_H */ 305