1/* 2 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28/* 29 * @OSF_COPYRIGHT@ 30 */ 31/* 32 * Mach Operating System 33 * Copyright (c) 1991,1990,1989 Carnegie Mellon University 34 * All Rights Reserved. 35 * 36 * Permission to use, copy, modify and distribute this software and its 37 * documentation is hereby granted, provided that both the copyright 38 * notice and this permission notice appear in all copies of the 39 * software, derivative works or modified versions, and any portions 40 * thereof, and that both notices appear in supporting documentation. 41 * 42 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 43 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 44 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 45 * 46 * Carnegie Mellon requests users of this software to return to 47 * 48 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 49 * School of Computer Science 50 * Carnegie Mellon University 51 * Pittsburgh PA 15213-3890 52 * 53 * any improvements or extensions that they make and grant Carnegie Mellon 54 * the rights to redistribute these changes. 55 */ 56/* 57 * NOTICE: This file was modified by McAfee Research in 2004 to introduce 58 * support for mandatory and extensible security protections. This notice 59 * is included in support of clause 2.2 (b) of the Apple Public License, 60 * Version 2.0. 61 */ 62/* 63 */ 64/* 65 * File: ipc/ipc_space.c 66 * Author: Rich Draves 67 * Date: 1989 68 * 69 * Functions to manipulate IPC capability spaces. 70 */ 71 72#include <mach/boolean.h> 73#include <mach/kern_return.h> 74#include <mach/port.h> 75#include <kern/assert.h> 76#include <kern/sched_prim.h> 77#include <kern/zalloc.h> 78#include <ipc/port.h> 79#include <ipc/ipc_entry.h> 80#include <ipc/ipc_object.h> 81#include <ipc/ipc_hash.h> 82#include <ipc/ipc_table.h> 83#include <ipc/ipc_port.h> 84#include <ipc/ipc_space.h> 85#include <ipc/ipc_right.h> 86#include <string.h> 87 88zone_t ipc_space_zone; 89ipc_space_t ipc_space_kernel; 90ipc_space_t ipc_space_reply; 91 92/* 93 * Routine: ipc_space_reference 94 * Routine: ipc_space_release 95 * Purpose: 96 * Function versions of the IPC space inline reference. 97 */ 98 99void 100ipc_space_reference( 101 ipc_space_t space) 102{ 103 is_reference(space); 104} 105 106void 107ipc_space_release( 108 ipc_space_t space) 109{ 110 is_release(space); 111} 112 113/* 114 * Routine: ipc_space_create 115 * Purpose: 116 * Creates a new IPC space. 117 * 118 * The new space has two references, one for the caller 119 * and one because it is active. 120 * Conditions: 121 * Nothing locked. Allocates memory. 122 * Returns: 123 * KERN_SUCCESS Created a space. 124 * KERN_RESOURCE_SHORTAGE Couldn't allocate memory. 125 */ 126 127kern_return_t 128ipc_space_create( 129 ipc_table_size_t initial, 130 ipc_space_t *spacep) 131{ 132 ipc_space_t space; 133 ipc_entry_t table; 134 ipc_entry_num_t new_size; 135 mach_port_index_t index; 136 137 space = is_alloc(); 138 if (space == IS_NULL) 139 return KERN_RESOURCE_SHORTAGE; 140 141 table = it_entries_alloc(initial); 142 if (table == IE_NULL) { 143 is_free(space); 144 return KERN_RESOURCE_SHORTAGE; 145 } 146 147 new_size = initial->its_size; 148 memset((void *) table, 0, new_size * sizeof(struct ipc_entry)); 149 150 /* 151 * Initialize the free list in the table. 152 * Add the entries in reverse order, and 153 * set the generation number to -1, so that 154 * initial allocations produce "natural" names. 155 */ 156 for (index = 0; index < new_size; index++) { 157 ipc_entry_t entry = &table[index]; 158 159 entry->ie_bits = IE_BITS_GEN_MASK; 160 entry->ie_next = index+1; 161 } 162 table[new_size-1].ie_next = 0; 163 164 is_lock_init(space); 165 space->is_bits = 2; /* 2 refs, active, not growing */ 166 space->is_table_size = new_size; 167 space->is_table_free = new_size - 1; 168 space->is_table = table; 169 space->is_table_next = initial+1; 170 space->is_task = NULL; 171 space->is_low_mod = new_size; 172 space->is_high_mod = 0; 173 174 *spacep = space; 175 return KERN_SUCCESS; 176} 177 178/* 179 * Routine: ipc_space_create_special 180 * Purpose: 181 * Create a special space. A special space 182 * doesn't hold rights in the normal way. 183 * Instead it is place-holder for holding 184 * disembodied (naked) receive rights. 185 * See ipc_port_alloc_special/ipc_port_dealloc_special. 186 * Conditions: 187 * Nothing locked. 188 * Returns: 189 * KERN_SUCCESS Created a space. 190 * KERN_RESOURCE_SHORTAGE Couldn't allocate memory. 191 */ 192 193kern_return_t 194ipc_space_create_special( 195 ipc_space_t *spacep) 196{ 197 ipc_space_t space; 198 199 space = is_alloc(); 200 if (space == IS_NULL) 201 return KERN_RESOURCE_SHORTAGE; 202 203 is_lock_init(space); 204 205 space->is_bits = IS_INACTIVE | 1; /* 1 ref, not active, not growing */ 206 space->is_table = IE_NULL; 207 space->is_task = TASK_NULL; 208 space->is_table_next = 0; 209 space->is_low_mod = 0; 210 space->is_high_mod = 0; 211 212 *spacep = space; 213 return KERN_SUCCESS; 214} 215 216/* 217 * ipc_space_clean - remove all port references from an ipc space. 218 * 219 * In order to follow the traditional semantic, ipc_space_destroy 220 * will not destroy the entire port table of a shared space. Instead 221 * it will simply clear its own sub-space. 222 */ 223void 224ipc_space_clean( 225 ipc_space_t space) 226{ 227 ipc_entry_t table; 228 ipc_entry_num_t size; 229 mach_port_index_t index; 230 231 /* 232 * If somebody is trying to grow the table, 233 * we must wait until they finish and figure 234 * out the space died. 235 */ 236 retry: 237 is_write_lock(space); 238 while (is_growing(space)) 239 is_write_sleep(space); 240 241 if (!is_active(space)) { 242 is_write_unlock(space); 243 return; 244 } 245 246 /* 247 * Now we can futz with it since we have the write lock. 248 */ 249 250 table = space->is_table; 251 size = space->is_table_size; 252 253 for (index = 0; index < size; index++) { 254 ipc_entry_t entry = &table[index]; 255 mach_port_type_t type; 256 257 type = IE_BITS_TYPE(entry->ie_bits); 258 if (type != MACH_PORT_TYPE_NONE) { 259 mach_port_name_t name = MACH_PORT_MAKE(index, 260 IE_BITS_GEN(entry->ie_bits)); 261 ipc_right_destroy(space, name, entry, FALSE, 0); /* unlocks space */ 262 goto retry; 263 } 264 } 265 266 /* 267 * JMM - Now the table is cleaned out. We don't bother shrinking the 268 * size of the table at this point, but we probably should if it is 269 * really large. 270 */ 271 272 is_write_unlock(space); 273} 274 275 276/* 277 * Routine: ipc_space_terminate 278 * Purpose: 279 * Marks the space as dead and cleans up the entries. 280 * Does nothing if the space is already dead. 281 * Conditions: 282 * Nothing locked. 283 */ 284 285void 286ipc_space_terminate( 287 ipc_space_t space) 288{ 289 ipc_entry_t table; 290 ipc_entry_num_t size; 291 mach_port_index_t index; 292 293 assert(space != IS_NULL); 294 295 is_write_lock(space); 296 if (!is_active(space)) { 297 is_write_unlock(space); 298 return; 299 } 300 is_mark_inactive(space); 301 302 /* 303 * If somebody is trying to grow the table, 304 * we must wait until they finish and figure 305 * out the space died. 306 */ 307 while (is_growing(space)) 308 is_write_sleep(space); 309 310 is_write_unlock(space); 311 312 313 /* 314 * Now we can futz with it unlocked. 315 */ 316 317 table = space->is_table; 318 size = space->is_table_size; 319 320 for (index = 0; index < size; index++) { 321 ipc_entry_t entry = &table[index]; 322 mach_port_type_t type; 323 324 type = IE_BITS_TYPE(entry->ie_bits); 325 if (type != MACH_PORT_TYPE_NONE) { 326 mach_port_name_t name; 327 328 name = MACH_PORT_MAKE(index, 329 IE_BITS_GEN(entry->ie_bits)); 330 ipc_right_terminate(space, name, entry); 331 } 332 } 333 334 it_entries_free(space->is_table_next-1, table); 335 space->is_table_size = 0; 336 space->is_table_free = 0; 337 338 /* 339 * Because the space is now dead, 340 * we must release the "active" reference for it. 341 * Our caller still has his reference. 342 */ 343 is_release(space); 344} 345 346 347