Differences From Artifact [ecdbc341ea]:
- File src/OFMapTable.m — part of check-in [f675979cf0] at 2012-12-06 11:00:50 on branch trunk — Add of_random(). (user: js, size: 16069) [annotate] [blame] [check-ins using]
To Artifact [fda4d04529]:
- File
src/OFMapTable.m
— part of check-in
[4857107479]
at
2012-12-06 11:00:54
on branch trunk
— OFMapTable: Rotate hash by a random number of bits
By rotating the hash by a random number of bits, an attacker needs to
find collisions on the full 32 bits of the hash and not only on the
lower n bits that are actually used by the map table, as an attacker
can't know which bits are actually used for the map table. (user: js, size: 16362) [annotate] [blame] [check-ins using]
| ︙ | |||
149 150 151 152 153 154 155 | 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 | - + + + | minCapacity = capacity; buckets = [self allocMemoryWithSize: sizeof(*buckets) count: capacity]; memset(buckets, 0, capacity * sizeof(*buckets)); |
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228 229 230 231 232 233 234 | 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 | + - + + |
@try {
uint32_t i;
for (i = 0; i < capacity; i++)
if (buckets[i] != NULL && buckets[i] != &deleted)
[copy OF_setValue: buckets[i]->value
forKey: buckets[i]->key
hash: OF_ROR(
|
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253 254 255 256 257 258 259 | 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 | - + | uint32_t i, hash, last; if (key == NULL) @throw [OFInvalidArgumentException exceptionWithClass: [self class] selector: _cmd]; |
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285 286 287 288 289 290 291 292 293 294 295 296 297 298 | 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 | + |
return NULL;
}
- (void)OF_resizeForCount: (uint32_t)newCount
{
uint32_t i, fullness, newCapacity, newSeed = 0, seedUpdate = 0;
struct of_map_table_bucket **newBuckets;
uint8_t newRotate = 0;
if (newCount > UINT32_MAX || newCount > UINT32_MAX / sizeof(*buckets) ||
newCount > UINT32_MAX / 8)
@throw [OFOutOfRangeException exceptionWithClass: [self class]];
fullness = newCount * 8 / capacity;
|
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311 312 313 314 315 316 317 318 319 320 321 322 323 | 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 | + + - + + + |
for (i = 0; i < newCapacity; i++)
newBuckets[i] = NULL;
if (of_hash_seed != 0) {
newSeed = of_random();
seedUpdate = seed ^ newSeed;
newRotate = of_random() & 0x1F;
}
for (i = 0; i < capacity; i++) {
if (buckets[i] != NULL && buckets[i] != &deleted) {
uint32_t j, last;
|
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342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 | 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 | + - + |
}
}
[self freeMemory: buckets];
buckets = newBuckets;
capacity = newCapacity;
seed = newSeed;
rotate = newRotate;
}
- (void)OF_setValue: (void*)value
forKey: (void*)key
hash: (uint32_t)hash
{
uint32_t i, last, seededHash;
void *old;
if (key == NULL || value == NULL)
@throw [OFInvalidArgumentException
exceptionWithClass: [self class]
selector: _cmd];
last = capacity;
|
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387 388 389 390 391 392 393 | 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 | - + |
/* Key not in dictionary */
if (i >= last || buckets[i] == NULL || buckets[i] == &deleted ||
!keyFunctions.equal(buckets[i]->key, key)) {
struct of_map_table_bucket *bucket;
[self OF_resizeForCount: count + 1];
|
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454 455 456 457 458 459 460 | 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 | - + | uint32_t i, hash, last; if (key == NULL) @throw [OFInvalidArgumentException exceptionWithClass: [self class] selector: _cmd]; |
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