OSX/sec/Security/SecOTRPacketData.h

   1 /*
   2  * Copyright (c) 2011-2014 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24
  25 #ifndef _SECOTRPACKETDATA_H_
  26 #define _SECOTRPACKETDATA_H_
  27
  28 #include <CoreFoundation/CFBase.h>
  29 #include <CoreFoundation/CFRuntime.h>
  30 #include <CoreFoundation/CFData.h>
  31
  32 #include <corecrypto/ccn.h>
  33
  34 #include <CommonCrypto/CommonDigest.h>
  35
  36 #include <Security/SecBase.h>
  37
  38 #include <Security/SecOTRPackets.h>
  39
  40 #include <AssertMacros.h>
  41
  42 __BEGIN_DECLS
  43
  44 static CC_NONNULL((1,2))
  45 OSStatus ReadAndVerifyByte(const uint8_t**bytes, size_t*size, uint8_t expected);
  46
  47 static CC_NONNULL((1,2))
  48 OSStatus ReadAndVerifyShort(const uint8_t**bytes, size_t*size, uint16_t expected);
  49
  50 static CC_NONNULL((1,2))
  51 OSStatus ReadAndVerifyMessageType(const uint8_t**bytes, size_t*size, OTRMessageType expected);
  52
  53 static CC_NONNULL((1,2,3,4))
  54 OSStatus SizeAndSkipDATA(const uint8_t **bytes, size_t *size,
  55                          const uint8_t **dataBytes, size_t *dataSize);
  56 static CC_NONNULL((1,2,3,4))
  57 OSStatus SizeAndSkipMPI(const uint8_t **bytes, size_t *size,
  58                         const uint8_t **mpiBytes, size_t *mpiSize);
  59
  60
  61 static CC_NONNULL((1,2,3))
  62 OSStatus ReadLongLongCompact(const uint8_t**bytesPtr, size_t*sizePtr, uint64_t* value);
  63
  64 static CC_NONNULL((1,2,3))
  65 OSStatus ReadLongLong(const uint8_t**bytesPtr, size_t*sizePtr, uint64_t* value);
  66
  67 static CC_NONNULL((1,2,3))
  68 OSStatus ReadLong(const uint8_t**bytesPtr, size_t*sizePtr, uint32_t* value);
  69
  70 static CC_NONNULL((1,2,3))
  71 OSStatus ReadShort(const uint8_t**bytesPtr, size_t*sizePtr, uint16_t* value);
  72
  73 static CC_NONNULL((1,2,3))
  74 OSStatus ReadByte(const uint8_t**bytesPtr, size_t*sizePtr, uint8_t* value);
  75
  76 static CC_NONNULL((1,2,3))
  77 OSStatus ReadMessageType(const uint8_t**bytesPtr, size_t*sizePtr, OTRMessageType* type);
  78
  79 static CC_NONNULL((1,2,4))
  80 OSStatus ReadMPI(const uint8_t**bytesPtr, size_t*sizePtr, cc_size n, cc_unit *x);
  81
  82 static CC_NONNULL((1,2,3,4))
  83 OSStatus ReadDATA(const uint8_t**bytesPtr, size_t*sizePtr, size_t* dataSize, uint8_t* data);
  84
  85 static CC_NONNULL((1,2,3))
  86 OSStatus CreatePublicKey(const uint8_t**bytesPtr, size_t*sizePtr, SecOTRPublicIdentityRef* publicId);
  87
  88 static CC_NONNULL((2,3))
  89 CFMutableDataRef CFDataCreateMutableFromOTRDATA(CFAllocatorRef allocator, const uint8_t**bytesPtr, size_t*sizePtr);
  90
  91 static CC_NONNULL((1))
  92 void AppendLongLongCompact(CFMutableDataRef appendTo, uint64_t value);
  93
  94 static CC_NONNULL((1))
  95 void AppendLongLong(CFMutableDataRef appendTo, uint64_t value);
  96
  97 static CC_NONNULL((1))
  98 void AppendLong(CFMutableDataRef appendTo, uint32_t value);
  99
 100 static CC_NONNULL((1))
 101 void AppendShort(CFMutableDataRef appendTo, uint16_t value);
 102
 103 static CC_NONNULL((1))
 104 void AppendByte(CFMutableDataRef appendTo, uint8_t type);
 105
 106 static CC_NONNULL((1))
 107 void AppendMessageType(CFMutableDataRef appendTo, OTRMessageType type);
 108
 109 static CC_NONNULL((1,3))
 110 void AppendMPI(CFMutableDataRef appendTo, cc_size n, const cc_unit *x);
 111
 112 static CC_NONNULL((1,3))
 113 void AppendDATA(CFMutableDataRef appendTo, size_t size, const uint8_t*data);
 114
 115 static CC_NONNULL((1,2))
 116 void AppendPublicKey(CFMutableDataRef appendTo, SecOTRPublicIdentityRef publicId);
 117
 118
 119 //
 120 // Inline implementation
 121 //
 122
 123 static uint16_t kCurrentOTRVersion = 0x2;
 124
 125 static inline OSStatus ReadLongLong(const uint8_t**bytesPtr, size_t*sizePtr, uint64_t* value)
 126 {
 127     require(bytesPtr != NULL, fail);
 128     require(sizePtr != NULL, fail);
 129     require(value != NULL, fail);
 130     require(*sizePtr >= 8, fail);
 131
 132     *value = ((uint64_t)(*bytesPtr)[0]) << 56 |
 133     ((uint64_t)(*bytesPtr)[1]) << 48 |
 134     ((uint64_t)(*bytesPtr)[2]) << 40 |
 135     ((uint64_t)(*bytesPtr)[3]) << 32 |
 136     ((uint64_t)(*bytesPtr)[4]) << 24 |
 137     ((uint64_t)(*bytesPtr)[5]) << 16 |
 138     ((uint64_t)(*bytesPtr)[6]) << 8  |
 139     ((uint64_t)(*bytesPtr)[7]) << 0;
 140
 141     *bytesPtr += 8;
 142     *sizePtr -= 8;
 143
 144     return errSecSuccess;
 145 fail:
 146     return errSecParam;
 147 }
 148
 149 static inline OSStatus ReadLongLongCompact(const uint8_t**bytesPtr, size_t*sizePtr, uint64_t* value)
 150 {
 151     bool moreBytes = true;
 152
 153     require(bytesPtr != NULL, fail);
 154     require(sizePtr != NULL, fail);
 155     require(value != NULL, fail);
 156
 157     *value = 0;
 158
 159     while (moreBytes && *sizePtr > 0) {
 160         uint8_t thisByte = **bytesPtr;
 161
 162         moreBytes = (0x80 & thisByte) != 0;
 163
 164         *value <<= 7;
 165         *value |= (thisByte & 0x7F);
 166
 167         ++*bytesPtr;
 168         --*sizePtr;
 169     }
 170
 171 fail:
 172     return !moreBytes ? errSecSuccess : errSecDecode;
 173 }
 174
 175 static inline OSStatus ReadLong(const uint8_t**bytesPtr, size_t*sizePtr, uint32_t* value)
 176 {
 177     require(bytesPtr != NULL, fail);
 178     require(sizePtr != NULL, fail);
 179     require(value != NULL, fail);
 180     require(*sizePtr >= 4, fail);
 181
 182     *value = (uint32_t)(*bytesPtr)[0] << 24 |
 183     (uint32_t)(*bytesPtr)[1] << 16 |
 184     (uint32_t)(*bytesPtr)[2] << 8  |
 185     (uint32_t)(*bytesPtr)[3] << 0;
 186
 187     *bytesPtr += 4;
 188     *sizePtr -= 4;
 189
 190     return errSecSuccess;
 191 fail:
 192     return errSecParam;
 193 }
 194
 195 static inline OSStatus ReadShort(const uint8_t**bytesPtr, size_t*sizePtr, uint16_t* value)
 196 {
 197     require(bytesPtr != NULL, fail);
 198     require(sizePtr != NULL, fail);
 199     require(value != NULL, fail);
 200     require(*sizePtr >= 2, fail);
 201
 202     *value = (*bytesPtr)[0] << 8  |
 203     (*bytesPtr)[1] << 0;
 204
 205     *bytesPtr += 2;
 206     *sizePtr -= 2;
 207
 208     return errSecSuccess;
 209 fail:
 210     return errSecParam;
 211 }
 212
 213 static inline OSStatus ReadByte(const uint8_t**bytesPtr, size_t*sizePtr, uint8_t* value)
 214 {
 215     require(bytesPtr != NULL, fail);
 216     require(sizePtr != NULL, fail);
 217     require(value != NULL, fail);
 218     require(*sizePtr >= 1, fail);
 219
 220     *value = *bytesPtr[0];
 221
 222     *bytesPtr += 1;
 223     *sizePtr -= 1;
 224
 225     return errSecSuccess;
 226 fail:
 227     return errSecParam;
 228 }
 229
 230 static inline OSStatus ReadByteAsBool(const uint8_t**bytesPtr, size_t*sizePtr, bool* value)
 231 {
 232     uint8_t byte = 0;
 233
 234     OSStatus result = ReadByte(bytesPtr, sizePtr, &byte);
 235
 236     if (result == noErr)
 237         *value = byte != 0;
 238
 239     return result;
 240 }
 241
 242 static inline OSStatus ReadMessageType(const uint8_t**bytesPtr, size_t*sizePtr, OTRMessageType* type)
 243 {
 244     OSStatus result = errSecParam;
 245     uint8_t value;
 246
 247     require(type != NULL, fail);
 248     require_noerr_quiet(result = ReadByte(bytesPtr, sizePtr, &value), fail);
 249
 250     *type = value;
 251 fail:
 252     return result;
 253 }
 254
 255 static inline OSStatus ReadMPI(const uint8_t**bytesPtr, size_t*sizePtr, cc_size n, cc_unit *x)
 256 {
 257     require(bytesPtr != NULL, fail);
 258     require(sizePtr != NULL, fail);
 259     require(x != NULL, fail);
 260     require_quiet(*sizePtr >= 5, fail);
 261
 262     uint32_t mpiLength;
 263
 264     ReadLong(bytesPtr, sizePtr, &mpiLength);
 265
 266     require_quiet(mpiLength <= *sizePtr, fail);
 267
 268     ccn_read_uint(n, x, mpiLength, *bytesPtr);
 269
 270     *bytesPtr += mpiLength;
 271     *sizePtr -= mpiLength;
 272
 273     return errSecSuccess;
 274 fail:
 275     return errSecParam;
 276
 277 }
 278
 279 static inline OSStatus ReadDATA(const uint8_t**bytesPtr, size_t*sizePtr, size_t* dataSize, uint8_t* data)
 280 {
 281     require(bytesPtr != NULL, fail);
 282     require(sizePtr != NULL, fail);
 283     require(data != NULL, fail);
 284     require_quiet(*sizePtr >= 5, fail);
 285
 286     uint32_t dataLength;
 287
 288     ReadLong(bytesPtr, sizePtr, &dataLength);
 289
 290     require_quiet(dataLength <= *sizePtr, fail);
 291     memmove(data, bytesPtr, dataLength);
 292
 293     *bytesPtr += dataLength;
 294     *sizePtr -= dataLength;
 295
 296     *dataSize = dataLength;
 297
 298     return errSecSuccess;
 299 fail:
 300     return errSecParam;
 301
 302 }
 303
 304 static inline OSStatus CreatePublicKey(const uint8_t**bytesPtr, size_t*sizePtr, SecOTRPublicIdentityRef* publicId)
 305 {
 306     require(bytesPtr != NULL, fail);
 307     require(sizePtr != NULL, fail);
 308     require(publicId != NULL, fail);
 309     require(*sizePtr >= 7, fail);
 310
 311     uint16_t type = 0;
 312     ReadShort(bytesPtr, sizePtr, &type);
 313
 314     require_quiet(type == 0xF000, fail);
 315     require_quiet(*sizePtr >= 5, fail);
 316
 317     uint32_t serializedIDLength = 0;
 318     ReadLong(bytesPtr, sizePtr, &serializedIDLength);
 319
 320     require_quiet(*sizePtr >= serializedIDLength, fail);
 321     require_quiet(((CFIndex)serializedIDLength) >= 0, fail);
 322
 323     CFDataRef serializedBytes = CFDataCreateWithBytesNoCopy(kCFAllocatorDefault, *bytesPtr, (CFIndex)serializedIDLength, kCFAllocatorNull);
 324
 325     *publicId = SecOTRPublicIdentityCreateFromData(kCFAllocatorDefault, serializedBytes, NULL);
 326
 327     *bytesPtr += serializedIDLength;
 328     *sizePtr -= serializedIDLength;
 329
 330     if(serializedBytes)
 331         CFRelease(serializedBytes);
 332
 333     return errSecSuccess;
 334 fail:
 335     return errSecParam;
 336
 337 }
 338
 339 static inline CFMutableDataRef CFDataCreateMutableFromOTRDATA(CFAllocatorRef allocator, const uint8_t**bytesPtr, size_t*sizePtr)
 340 {
 341     CFMutableDataRef result = NULL;
 342     uint32_t sizeInStream;
 343     require_noerr_quiet(ReadLong(bytesPtr, sizePtr, &sizeInStream), exit);
 344     require_quiet(sizeInStream <= *sizePtr, exit);
 345     require_quiet(((CFIndex)sizeInStream) >= 0, exit);
 346
 347     result = CFDataCreateMutable(allocator, 0);
 348
 349     CFDataAppendBytes(result, *bytesPtr, (CFIndex)sizeInStream);
 350
 351     *bytesPtr += sizeInStream;
 352     *sizePtr -= sizeInStream;
 353
 354 exit:
 355     return result;
 356 }
 357
 358
 359 //
 360 // Parse and verify functions
 361 //
 362 static inline OSStatus ReadAndVerifyByte(const uint8_t**bytes, size_t*size, uint8_t expected)
 363 {
 364     uint8_t found;
 365     OSStatus result = ReadByte(bytes, size, &found);
 366     require_noerr_quiet(result, exit);
 367     require_action_quiet(found == expected, exit, result = errSecDecode);
 368 exit:
 369     return result;
 370 }
 371
 372 static inline OSStatus ReadAndVerifyShort(const uint8_t**bytes, size_t*size, uint16_t expected)
 373 {
 374     uint16_t found;
 375     OSStatus result = ReadShort(bytes, size, &found);
 376     require_noerr_quiet(result, exit);
 377     require_action_quiet(found == expected, exit, result = errSecDecode);
 378 exit:
 379     return result;
 380 }
 381
 382 static inline OSStatus ReadAndVerifyMessageType(const uint8_t**bytes, size_t*size, OTRMessageType expected)
 383 {
 384     OTRMessageType found;
 385     OSStatus result = ReadMessageType(bytes, size, &found);
 386     require_noerr_quiet(result, exit);
 387     require_action_quiet(found == expected, exit, result = errSecDecode);
 388 exit:
 389     return result;
 390 }
 391
 392 static inline OSStatus ReadAndVerifyVersion(const uint8_t**bytes, size_t*size)
 393 {
 394     return ReadAndVerifyShort(bytes, size, kCurrentOTRVersion);
 395 }
 396
 397 static inline OSStatus ReadAndVerifyHeader(const uint8_t**bytes, size_t*size, OTRMessageType expected)
 398 {
 399     OSStatus result = ReadAndVerifyVersion(bytes, size);
 400     require_noerr_quiet(result, exit);
 401
 402     result = ReadAndVerifyMessageType(bytes, size, expected);
 403     require_noerr_quiet(result, exit);
 404
 405 exit:
 406     return result;
 407 }
 408
 409 static inline OSStatus ReadHeader(const uint8_t**bytes, size_t*size, OTRMessageType *messageType)
 410 {
 411     OSStatus result = ReadAndVerifyVersion(bytes, size);
 412     require_noerr_quiet(result, exit);
 413
 414     result = ReadMessageType(bytes, size, messageType);
 415     require_noerr_quiet(result, exit);
 416
 417 exit:
 418     return result;
 419 }
 420
 421 static inline OSStatus SizeAndSkipDATA(const uint8_t **bytes, size_t *size,
 422                                 const uint8_t **dataBytes, size_t *dataSize)
 423 {
 424     OSStatus result;
 425     uint32_t sizeRead;
 426     result = ReadLong(bytes, size, &sizeRead);
 427
 428     require_noerr_quiet(result, exit);
 429     require_action_quiet(sizeRead <= *size, exit, result = errSecDecode);
 430
 431     *dataSize = sizeRead;
 432     *dataBytes = *bytes;
 433     *bytes += sizeRead;
 434     *size -= sizeRead;
 435 exit:
 436     return result;
 437 }
 438
 439 static inline OSStatus SizeAndSkipMPI(const uint8_t **bytes, size_t *size,
 440                                const uint8_t **mpiBytes, size_t *mpiSize)
 441 {
 442     // MPIs looke like data for skipping.
 443     return SizeAndSkipDATA(bytes, size, mpiBytes, mpiSize);
 444 }
 445
 446
 447 //
 448 // Appending functions
 449 //
 450 static inline void AppendLongLongCompact(CFMutableDataRef appendTo, uint64_t value)
 451 {
 452     uint8_t compact[(sizeof(value) * 8 + 7) / 7]; // We can only need enough bytes to hold 8/7 expansion.
 453
 454     uint8_t *end = compact + sizeof(compact);
 455     uint8_t *lastFilled = end;
 456
 457     --lastFilled;
 458     *lastFilled = (value & 0x7F);
 459
 460     for (value >>= 7; value != 0; value >>= 7) {
 461         --lastFilled;
 462         *lastFilled = (value & 0x7f) | 0x80;
 463     }
 464
 465     CFDataAppendBytes(appendTo, lastFilled, end - lastFilled);
 466 }
 467
 468 static inline void AppendLongLong(CFMutableDataRef appendTo, uint64_t value)
 469 {
 470     uint8_t bigEndian[sizeof(value)] = { value >> 56, value >> 48, value >> 40, value >> 32,
 471                                          value >> 24, value >> 16, value >> 8 , value >> 0  };
 472
 473     CFDataAppendBytes(appendTo, bigEndian, sizeof(bigEndian));
 474 }
 475
 476 static inline void AppendLong(CFMutableDataRef appendTo, uint32_t value)
 477 {
 478     uint8_t bigEndian[sizeof(value)] = { value >> 24, value >> 16, value >> 8, value };
 479
 480     CFDataAppendBytes(appendTo, bigEndian, sizeof(bigEndian));
 481 }
 482
 483 static inline void AppendShort(CFMutableDataRef appendTo, uint16_t value)
 484 {
 485     uint8_t bigEndian[sizeof(value)] = { value >> 8, value };
 486
 487     CFDataAppendBytes(appendTo, bigEndian, sizeof(bigEndian));
 488 }
 489
 490 static inline void AppendByte(CFMutableDataRef appendTo, uint8_t byte)
 491 {
 492     CFDataAppendBytes(appendTo, &byte, 1);
 493 }
 494
 495 static inline void AppendMessageType(CFMutableDataRef appendTo, OTRMessageType type)
 496 {
 497     AppendByte(appendTo, type);
 498 }
 499
 500 static inline void AppendMPI(CFMutableDataRef appendTo, cc_size n, const cc_unit *x)
 501 {
 502     size_t size = ccn_write_uint_size(n, x);
 503     /* 64 bits cast: we are appending an identity, whose size is hardcoded and less then 2^32 bytes */
 504     /* Worst case is we encoded a truncated length. No security issue. */
 505     assert(size<UINT32_MAX); /* Debug check */
 506     AppendLong(appendTo, (uint32_t)size);
 507     assert(((CFIndex)size) >= 0);
 508     CFIndex startOffset = CFDataGetLength(appendTo);
 509     CFDataIncreaseLength(appendTo, (CFIndex)size);
 510     uint8_t* insertionPtr = CFDataGetMutableBytePtr(appendTo) + startOffset;
 511     ccn_write_uint(n, x, size, insertionPtr);
 512 }
 513
 514 static inline void AppendDATA(CFMutableDataRef appendTo, size_t size, const uint8_t*data)
 515 {
 516     /* 64 bits cast: we are appending Public Key or Signature, whose sizes are hardcoded and less then 2^32 bytes */
 517     /* Worst case is we encoded a truncated length. No security issue. */
 518     assert(size<=UINT32_MAX); /* Debug check */
 519     AppendLong(appendTo, (uint32_t)size);
 520     assert(((CFIndex)size) >= 0);
 521     CFDataAppendBytes(appendTo, data, (CFIndex)size);
 522 }
 523
 524 static inline void AppendCFDataAsDATA(CFMutableDataRef appendTo, CFDataRef dataToAppend)
 525 {
 526     AppendDATA(appendTo, (size_t)CFDataGetLength(dataToAppend), CFDataGetBytePtr(dataToAppend));
 527 }
 528
 529 static inline void AppendPublicKey(CFMutableDataRef appendTo, SecOTRPublicIdentityRef publicId)
 530 {
 531     AppendShort(appendTo, 0xF000); // Custom type reserved by no one
 532
 533     CFMutableDataRef serializedID = CFDataCreateMutable(kCFAllocatorDefault, 0);
 534
 535     SecOTRPIAppendSerialization(publicId, serializedID, NULL);
 536     AppendDATA(appendTo, (size_t)CFDataGetLength(serializedID), CFDataGetBytePtr(serializedID));
 537
 538     if(serializedID)
 539         CFRelease(serializedID);
 540 }
 541
 542 static inline void AppendVersion(CFMutableDataRef appendTo)
 543 {
 544     AppendShort(appendTo, kCurrentOTRVersion);
 545 }
 546
 547 static inline void AppendHeader(CFMutableDataRef appendTo, OTRMessageType type)
 548 {
 549     AppendVersion(appendTo);
 550     AppendMessageType(appendTo, type);
 551 }
 552
 553 __END_DECLS
 554
 555 #endif