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 = table; 168 space->is_table_next = initial+1; 169 space->is_task = NULL; 170 space->is_low_mod = new_size; 171 space->is_high_mod = 0; 172 173 *spacep = space; 174 return KERN_SUCCESS; 175} 176 177/* 178 * Routine: ipc_space_create_special 179 * Purpose: 180 * Create a special space. A special space 181 * doesn't hold rights in the normal way. 182 * Instead it is place-holder for holding 183 * disembodied (naked) receive rights. 184 * See ipc_port_alloc_special/ipc_port_dealloc_special. 185 * Conditions: 186 * Nothing locked. 187 * Returns: 188 * KERN_SUCCESS Created a space. 189 * KERN_RESOURCE_SHORTAGE Couldn't allocate memory. 190 */ 191 192kern_return_t 193ipc_space_create_special( 194 ipc_space_t *spacep) 195{ 196 ipc_space_t space; 197 198 space = is_alloc(); 199 if (space == IS_NULL) 200 return KERN_RESOURCE_SHORTAGE; 201 202 is_lock_init(space); 203 204 space->is_bits = IS_INACTIVE | 1; /* 1 ref, not active, not growing */ 205 space->is_table = IE_NULL; 206 space->is_task = TASK_NULL; 207 space->is_table_next = 0; 208 space->is_low_mod = 0; 209 space->is_high_mod = 0; 210 211 *spacep = space; 212 return KERN_SUCCESS; 213} 214 215/* 216 * ipc_space_clean - remove all port references from an ipc space. 217 * 218 * In order to follow the traditional semantic, ipc_space_destroy 219 * will not destroy the entire port table of a shared space. Instead 220 * it will simply clear its own sub-space. 221 */ 222void 223ipc_space_clean( 224 ipc_space_t space) 225{ 226 ipc_entry_t table; 227 ipc_entry_num_t size; 228 mach_port_index_t index; 229 230 /* 231 * If somebody is trying to grow the table, 232 * we must wait until they finish and figure 233 * out the space died. 234 */ 235 retry: 236 is_write_lock(space); 237 while (is_growing(space)) 238 is_write_sleep(space); 239 240 if (!is_active(space)) { 241 is_write_unlock(space); 242 return; 243 } 244 245 /* 246 * Now we can futz with it since we have the write lock. 247 */ 248 249 table = space->is_table; 250 size = space->is_table_size; 251 252 for (index = 0; index < size; index++) { 253 ipc_entry_t entry = &table[index]; 254 mach_port_type_t type; 255 256 type = IE_BITS_TYPE(entry->ie_bits); 257 if (type != MACH_PORT_TYPE_NONE) { 258 mach_port_name_t name = MACH_PORT_MAKE(index, 259 IE_BITS_GEN(entry->ie_bits)); 260 ipc_right_destroy(space, name, entry, FALSE, 0); /* unlocks space */ 261 goto retry; 262 } 263 } 264 265 /* 266 * JMM - Now the table is cleaned out. We don't bother shrinking the 267 * size of the table at this point, but we probably should if it is 268 * really large. 269 */ 270 271 is_write_unlock(space); 272} 273 274 275/* 276 * Routine: ipc_space_terminate 277 * Purpose: 278 * Marks the space as dead and cleans up the entries. 279 * Does nothing if the space is already dead. 280 * Conditions: 281 * Nothing locked. 282 */ 283 284void 285ipc_space_terminate( 286 ipc_space_t space) 287{ 288 ipc_entry_t table; 289 ipc_entry_num_t size; 290 mach_port_index_t index; 291 292 assert(space != IS_NULL); 293 294 is_write_lock(space); 295 if (!is_active(space)) { 296 is_write_unlock(space); 297 return; 298 } 299 is_mark_inactive(space); 300 301 /* 302 * If somebody is trying to grow the table, 303 * we must wait until they finish and figure 304 * out the space died. 305 */ 306 while (is_growing(space)) 307 is_write_sleep(space); 308 309 is_write_unlock(space); 310 311 312 /* 313 * Now we can futz with it unlocked. 314 */ 315 316 table = space->is_table; 317 size = space->is_table_size; 318 319 for (index = 0; index < size; index++) { 320 ipc_entry_t entry = &table[index]; 321 mach_port_type_t type; 322 323 type = IE_BITS_TYPE(entry->ie_bits); 324 if (type != MACH_PORT_TYPE_NONE) { 325 mach_port_name_t name; 326 327 name = MACH_PORT_MAKE(index, 328 IE_BITS_GEN(entry->ie_bits)); 329 ipc_right_terminate(space, name, entry); 330 } 331 } 332 333 it_entries_free(space->is_table_next-1, table); 334 space->is_table_size = 0; 335 336 /* 337 * Because the space is now dead, 338 * we must release the "active" reference for it. 339 * Our caller still has his reference. 340 */ 341 is_release(space); 342} 343 344 345