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 26 27 #ifndef _NS_CONNMGMT_H 28 #define _NS_CONNMGMT_H 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 #ifdef __cplusplus 33 extern "C" { 34 #endif 35 36 #include <thread.h> 37 #include "ns_sldap.h" 38 #include "ns_internal.h" 39 #include "ns_cache_door.h" 40 41 struct ns_conn_user; /* connection user, forward definition */ 42 struct ns_conn_mt; /* multi-threaded (MT) connection, forward definition */ 43 struct ns_conn_mgmt; /* connection management, forward definition */ 44 45 #define NS_CONN_MT_USER_NO_MAX -1 46 #define NS_CONN_MT_USER_MAX NS_CONN_MT_USER_NO_MAX 47 #define NS_LIST_TRY_MAX 3 48 49 /* 50 * Structure for handling the waiter of a pending multi-threaded (MT) connection 51 */ 52 typedef struct ns_conn_waiter { 53 cond_t waitcv; 54 uint8_t signaled; 55 struct ns_conn_user *key; 56 struct ns_conn_waiter *next, *prev; 57 } ns_conn_waiter_t; 58 59 /* 60 * type of a connection user 61 */ 62 typedef enum { 63 NS_CONN_USER_SEARCH = 1, 64 NS_CONN_USER_WRITE = 2, 65 NS_CONN_USER_AUTH = 3, 66 NS_CONN_USER_GETENT = 4 67 } ns_conn_user_type_t; 68 69 /* 70 * state of a connection user 71 */ 72 typedef enum { 73 NS_CONN_USER_UNINITED = 0, 74 NS_CONN_USER_ALLOCATED = 1, 75 NS_CONN_USER_FINDING = 2, /* looking for an MT connection */ 76 NS_CONN_USER_WAITING = 3, /* waiting for an MT connection */ 77 NS_CONN_USER_WOKEUP = 4, 78 NS_CONN_USER_CONNECT_ERROR = 5, 79 NS_CONN_USER_CONNECTED = 6, 80 NS_CONN_USER_DISCONNECTED = 7, 81 NS_CONN_USER_FREED = 8 82 } ns_conn_user_state_t; 83 84 /* 85 * A connection user represents a request processed by libsldap. It 86 * usually is a thread using the same connection from start to end. 87 * Different connection users of the same type can share the same 88 * connection opened for that type. But search and getent users can 89 * share the same connection opened for either search or getent. AUTH 90 * connection are not shareable. 91 * 92 * A getent user may have a longer lifespan and live outside of libsldap. 93 * This is because the associated search cookie is passed back to the caller 94 * via the firstEntry call and used in the subsequent nextEntry or endEntry 95 * calls. Even though the firstEntry and the nextEntry/endEntry calls may 96 * be running in a different thread, the connection being used will be the 97 * same. It is the one assigend during the firstEntry call. 98 */ 99 struct ns_conn_user { 100 ns_conn_user_type_t type; /* search, write, auth, getent, ... */ 101 ns_conn_user_state_t state; 102 thread_t tid; /* id of the thread starts the request */ 103 struct ns_conn_user *next; /* next conn_user in the linked list */ 104 struct ns_conn_mt *conn_mt; /* the MT connection being used */ 105 struct ns_conn_mgmt *conn_mgmt; /* ref counted conn management */ 106 void *userinfo; /* private data of the request */ 107 ns_ldap_return_code ns_rc; /* error return code */ 108 ns_ldap_error_t *ns_error; /* error info */ 109 boolean_t referral; /* using a referred server ? */ 110 boolean_t retry; /* retry the request on certain error? */ 111 boolean_t keep_conn; /* keep the conn for reuse ? */ 112 boolean_t use_mt_conn; /* using/used an MT connection ? */ 113 boolean_t bad_mt_conn; /* MT connection is not usable ? */ 114 }; 115 116 /* 117 * state of an MT connection 118 */ 119 typedef enum { 120 NS_CONN_MT_UNINITED = 0, 121 NS_CONN_MT_CONNECTING = 1, 122 NS_CONN_MT_CONNECT_ERROR = 2, 123 NS_CONN_MT_CONNECTED = 3, 124 NS_CONN_MT_CLOSING = 4 125 } ns_conn_mt_state_t; 126 127 /* 128 * An ns_conn_mt (or MT connection) represents an ldap connection 129 * that can be shared among multiple threads. It also represents 130 * the set of connection users using the ldap connection. It contains 131 * a pointer to the Connection structure that has the physical info 132 * of the connection (server name, address, ldap handle, etc). It 133 * also contains a linked list of all the conn_user using the ldap 134 * connection. The connection users can wait on an MT connection 135 * to become available or be told to abort and clean up when one of 136 * the connection user detects an error and knows that the connection 137 * is no longer usable. The error info is then saved in the structure 138 * for other users to consume. 139 * 140 * An MT connection is meant to be shared concurrently and persistent. 141 * Even when there's no current user, it will be kept by the connection 142 * management, waiting for the next user. It will be closed when 143 * a connection error is detected, when a better server should be 144 * used, when the Native LDAP configuration change, or when the libsldap 145 * is being unloaded. 146 */ 147 typedef struct ns_conn_mt { 148 mutex_t lock; 149 ns_conn_mt_state_t state; 150 pid_t pid; /* process creates the connection */ 151 thread_t tid; /* thread creates the connection */ 152 struct ns_conn_mt *next; /* next conn_mt in the linked list */ 153 ns_conn_user_t *cu_head; /* head of conn_user linked list */ 154 ns_conn_user_t *cu_tail; /* tail of conn_user linked list */ 155 struct ns_conn_mgmt *conn_mgmt; /* ref counted conn management */ 156 ns_conn_waiter_t waiter; /* first of the connection waiters */ 157 uint_t cu_cnt; /* number of the using conn_user */ 158 int32_t cu_max; /* max. allowed number of conn_user */ 159 uint_t waiter_cnt; /* number of waiters */ 160 ns_conn_user_type_t opened_for; /* type of conn_user opened for */ 161 Connection *conn; /* name, IP address, ldap handle, etc */ 162 time_t create_time; /* time when connection created */ 163 time_t access_time; /* time when last used */ 164 ns_ldap_return_code ns_rc; /* saved error code */ 165 ns_ldap_error_t *ns_error; /* saved error info */ 166 boolean_t close_when_nouser; /* close connection when */ 167 /* last user is done ? */ 168 boolean_t detached; /* no longer in connection pool? */ 169 boolean_t referral; /* using a referred server ? */ 170 } ns_conn_mt_t; 171 172 /* 173 * state of a connection management 174 * (a connection pool sharing the same native LDAP configuration) 175 */ 176 typedef enum { 177 NS_CONN_MGMT_UNINITED = 0, 178 NS_CONN_MGMT_INACTIVE = 1, /* conn sharing not yet requested */ 179 NS_CONN_MGMT_ACTIVE = 2, /* connection sharing required/requested */ 180 NS_CONN_MGMT_DETACHED = 3 /* on the way down, no new user allowed */ 181 } ns_conn_mgmt_state_t; 182 183 /* 184 * An ns_conn_mgmt (or connection management) represents the set of MT 185 * connections using the same native LDAP configuration. It is a connection 186 * pool that can adjust the MT connection status and usage based on the 187 * change notifications it receives from the ldap_cachemgr daemon, OR When 188 * the change is detected at config refresh time. When a server status 189 * change (up or down) notification is received or detected, it will 190 * close the MT connections using the server. Or mark them as to-be-closed 191 * and close them when all users are done using them. When a config change 192 * notice is received, it will detach itself and allow a new ns_conn_mgmt be 193 * created for the new configuration. The old config would still be used 194 * by the detached ns_conn_mgmt. Both will be destroyed when all existing 195 * conn_user are done. Any conn_user and MT connection created after the 196 * configuration switch will use the new configuration. 197 * 198 * Note that there's always just one current ns_conn_mgmt. Its usage is 199 * reference counted. Any new conn_user or MT connection referencing 200 * the ns_conn_mgmt adds 1 to the count, any release of the ns_conn_mgmt 201 * decrement the count by 1. The ns_conn_mgmt can not be freed until 202 * the reference count becomes zero. 203 * 204 * Each ns_conn_mgmt references a native LDAP configuration. The config 205 * component of this library always maintains a global configuration. It is 206 * referred to as the current global config. The current ns_conn_mgmt 207 * uses that global config. When an ns_conn_mgmt is detached, or not 208 * longer active/current, the config it uses is no longer the current global 209 * one, which is referred as the per connection management config. When 210 * the ns_conn_mgmt is freed, the config will also be destroyed. 211 */ 212 213 typedef struct ns_conn_mgmt { 214 mutex_t lock; 215 ns_conn_mgmt_state_t state; 216 pid_t pid; /* process creates the conn_mgmt */ 217 thread_t procchg_tid; /* id of the change monitor thread */ 218 ns_conn_mt_t *cm_head; /* head of the conn_mt linked list */ 219 ns_conn_mt_t *cm_tail; /* tail of the conn_mt linked list */ 220 mutex_t cfg_lock; /* lock serializes access to config */ 221 ldap_get_chg_cookie_t cfg_cookie; /* used to detect if config changes */ 222 ns_config_t *config; /* the native LDAP config being used */ 223 char **pservers; /* preferred servers defined in config */ 224 uint_t cm_cnt; /* number of MT connection in the pool */ 225 uint_t ref_cnt; /* number of reference by conn_MT/conn_user */ 226 boolean_t is_nscd; /* running in a nscd ? */ 227 boolean_t is_peruser_nscd; /* running in a per-user nscd ? */ 228 boolean_t ldap_mt; /* libldap supports multi-threaded client ? */ 229 boolean_t do_mt_conn; /* need and able to do MT conn ? */ 230 boolean_t shutting_down; /* on the way down ? */ 231 boolean_t cfg_reloaded; /* config is not current ? */ 232 boolean_t procchg_started; /* change monitor thread started ? */ 233 boolean_t procchg_door_call; /* in door call and waiting ? */ 234 boolean_t pservers_loaded; /* pservers array is set ? */ 235 } ns_conn_mgmt_t; 236 237 /* 238 * For a connection management and the conn_mt connections it manages, it is 239 * very helpful to know exactly when the Native LDAP configuration changes 240 * and when the status of the configured servers change. If the config 241 * changes, new connection management will be created. If servers go up 242 * or down, conn_mt connections being used need to be dropped or switched. 243 * For processes other than the main nscd, the changes has to be detected 244 * in a less efficient way by libsldap. For the main nscd (not including 245 * peruser nscd), the connection management which has active conn_mt 246 * connections can rely on the ldap_cachemgr daemon to report if there's any 247 * change in servers' status or if the native LDAP configuration has changed. 248 * 249 * The mechanism for reporting of the changes is a door call sent from 250 * libsldap to ldap_cachemgr. The call will not be returned until changes 251 * detected by ldap_cachemgr. When the change info is passed back to 252 * libsldap, the change monitor thread will wake up from the door call 253 * and process the notification. For servers went from up to down, the 254 * associated MT connections will be closed, and then all conn_users' 255 * state will be marked as closing. When a conn_user notices it, the 256 * operations represented by that conn_user will be ended with error 257 * info. When a more preferred server is up, MT connections using 258 * less preferred servers will be marked as closed-when-all-user-done, 259 * so that new connection will be opened and using the preferred server. 260 * A configuration change causes the current connection management and 261 * the configuration it uses to become detached but continually being 262 * used by the old MT connections. Any new MT connection opened will 263 * be put in a new connection management and uses the new configuration 264 * immediately. 265 */ 266 typedef enum { 267 NS_SERVER_UP = 1, 268 NS_SERVER_DOWN = 2 269 } ns_server_status_t; 270 271 typedef struct ns_server_status_change { 272 int num_server; 273 boolean_t config_changed; 274 ns_server_status_t *changes; /* array of status change */ 275 char **servers; /* array of server */ 276 } ns_server_status_change_t; 277 278 /* 279 * connection management functions 280 */ 281 ns_conn_mgmt_t *__s_api_conn_mgmt_init(); 282 int __s_api_setup_mt_ld(LDAP *ld); 283 int __s_api_check_mtckey(); 284 void __s_api_use_prev_conn_mgmt(int, ns_config_t *); 285 ns_conn_user_t *__s_api_conn_user_init(int, void *, boolean_t); 286 void __s_api_conn_mt_return(ns_conn_user_t *); 287 void __s_api_conn_user_free(ns_conn_user_t *); 288 int __s_api_conn_mt_add(Connection *con, ns_conn_user_t *, ns_ldap_error_t **); 289 int __s_api_conn_mt_get(const char *, const int, const ns_cred_t *, 290 Connection **, ns_ldap_error_t **, ns_conn_user_t *); 291 void __s_api_conn_mt_remove(ns_conn_user_t *, int, ns_ldap_error_t **); 292 int __s_api_check_libldap_MT_conn_support(ns_conn_user_t *, LDAP *ld, 293 ns_ldap_error_t **); 294 void __s_api_conn_mt_close(ns_conn_user_t *, int, ns_ldap_error_t **); 295 void __s_api_reinit_conn_mgmt_new_config(ns_config_t *); 296 int __s_api_setup_retry_search(ns_conn_user_t **, ns_conn_user_type_t, int *, 297 int *, ns_ldap_error_t **); 298 int __s_api_setup_getnext(ns_conn_user_t *, int *, ns_ldap_error_t **); 299 void __s_api_shutdown_conn_mgmt(); 300 301 #ifdef __cplusplus 302 } 303 #endif 304 305 #endif /* _NS_CONNMGMT_H */ 306