1 /****************************************************************************** 2 * 3 * Copyright (C) 2010-2014 Broadcom Corporation 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at: 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 * 17 ******************************************************************************/ 18 19 /****************************************************************************** 20 * 21 * This file contains source code for some utility functions to help parse 22 * and build NFC Data Exchange Format (NDEF) messages 23 * 24 ******************************************************************************/ 25 #include "ndef_utils.h" 26 #include <string.h> 27 28 /******************************************************************************* 29 ** 30 ** Static Local Functions 31 ** 32 *******************************************************************************/ 33 34 /******************************************************************************* 35 ** 36 ** Function shiftdown 37 ** 38 ** Description shift memory down (to make space to insert a record) 39 ** 40 *******************************************************************************/ 41 static void shiftdown(uint8_t* p_mem, uint32_t len, uint32_t shift_amount) { 42 register uint8_t* ps = p_mem + len - 1; 43 register uint8_t* pd = ps + shift_amount; 44 register uint32_t xx; 45 46 for (xx = 0; xx < len; xx++) *pd-- = *ps--; 47 } 48 49 /******************************************************************************* 50 ** 51 ** Function shiftup 52 ** 53 ** Description shift memory up (to delete a record) 54 ** 55 *******************************************************************************/ 56 static void shiftup(uint8_t* p_dest, uint8_t* p_src, uint32_t len) { 57 register uint8_t* ps = p_src; 58 register uint8_t* pd = p_dest; 59 register uint32_t xx; 60 61 for (xx = 0; xx < len; xx++) *pd++ = *ps++; 62 } 63 64 /******************************************************************************* 65 ** 66 ** Function NDEF_MsgValidate 67 ** 68 ** Description This function validates an NDEF message. 69 ** 70 ** Returns TRUE if all OK, or FALSE if the message is invalid. 71 ** 72 *******************************************************************************/ 73 tNDEF_STATUS NDEF_MsgValidate(uint8_t* p_msg, uint32_t msg_len, 74 bool b_allow_chunks) { 75 uint8_t* p_rec = p_msg; 76 uint8_t* p_end = p_msg + msg_len; 77 uint8_t rec_hdr = 0, type_len, id_len; 78 int count; 79 uint32_t payload_len; 80 bool bInChunk = false; 81 82 if ((p_msg == NULL) || (msg_len < 3)) return (NDEF_MSG_TOO_SHORT); 83 84 /* The first record must have the MB bit set */ 85 if ((*p_msg & NDEF_MB_MASK) == 0) return (NDEF_MSG_NO_MSG_BEGIN); 86 87 /* The first record cannot be a chunk */ 88 if ((*p_msg & NDEF_TNF_MASK) == NDEF_TNF_UNCHANGED) 89 return (NDEF_MSG_UNEXPECTED_CHUNK); 90 91 for (count = 0; p_rec < p_end; count++) { 92 /* if less than short record header */ 93 if (p_rec + 3 > p_end) return (NDEF_MSG_TOO_SHORT); 94 95 rec_hdr = *p_rec++; 96 97 /* header should have a valid TNF */ 98 if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_MASK) 99 return NDEF_MSG_INVALID_CHUNK; 100 101 /* The second and all subsequent records must NOT have the MB bit set */ 102 if ((count > 0) && (rec_hdr & NDEF_MB_MASK)) 103 return (NDEF_MSG_EXTRA_MSG_BEGIN); 104 105 /* Type field length */ 106 type_len = *p_rec++; 107 108 /* If the record is chunked, first record must contain the type unless 109 * it's Type Name Format is Unknown */ 110 if ((rec_hdr & NDEF_CF_MASK) && (rec_hdr & NDEF_MB_MASK) && type_len == 0 && 111 (rec_hdr & NDEF_TNF_MASK) != NDEF_TNF_UNKNOWN) 112 return (NDEF_MSG_INVALID_CHUNK); 113 114 /* Payload length - can be 1 or 4 bytes */ 115 if (rec_hdr & NDEF_SR_MASK) 116 payload_len = *p_rec++; 117 else { 118 /* if less than 4 bytes payload length */ 119 if (p_rec + 4 > p_end) return (NDEF_MSG_TOO_SHORT); 120 121 BE_STREAM_TO_UINT32(payload_len, p_rec); 122 } 123 124 /* ID field Length */ 125 if (rec_hdr & NDEF_IL_MASK) { 126 /* if less than 1 byte ID field length */ 127 if (p_rec + 1 > p_end) return (NDEF_MSG_TOO_SHORT); 128 129 id_len = *p_rec++; 130 } else { 131 id_len = 0; 132 /* Empty record must have the id_len */ 133 if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_EMPTY) 134 return (NDEF_MSG_INVALID_EMPTY_REC); 135 } 136 137 /* A chunk must have type "unchanged", and no type or ID fields */ 138 if (rec_hdr & NDEF_CF_MASK) { 139 if (!b_allow_chunks) return (NDEF_MSG_UNEXPECTED_CHUNK); 140 141 /* Inside a chunk, the type must be unchanged and no type or ID field i 142 * sallowed */ 143 if (bInChunk) { 144 if ((type_len != 0) || (id_len != 0) || 145 ((rec_hdr & NDEF_TNF_MASK) != NDEF_TNF_UNCHANGED)) 146 return (NDEF_MSG_INVALID_CHUNK); 147 } else { 148 /* First record of a chunk must NOT have type "unchanged" */ 149 if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_UNCHANGED) 150 return (NDEF_MSG_INVALID_CHUNK); 151 152 bInChunk = true; 153 } 154 } else { 155 /* This may be the last guy in a chunk. */ 156 if (bInChunk) { 157 if ((type_len != 0) || (id_len != 0) || 158 ((rec_hdr & NDEF_TNF_MASK) != NDEF_TNF_UNCHANGED)) 159 return (NDEF_MSG_INVALID_CHUNK); 160 161 bInChunk = false; 162 } else { 163 /* If not in a chunk, the record must NOT have type "unchanged" */ 164 if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_UNCHANGED) 165 return (NDEF_MSG_INVALID_CHUNK); 166 } 167 } 168 169 /* An empty record must NOT have a type, ID or payload */ 170 if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_EMPTY) { 171 if ((type_len != 0) || (id_len != 0) || (payload_len != 0)) 172 return (NDEF_MSG_INVALID_EMPTY_REC); 173 } 174 175 if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_UNKNOWN) { 176 if (type_len != 0) return (NDEF_MSG_LENGTH_MISMATCH); 177 } 178 179 /* External type should have non-zero type length */ 180 if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_EXT) { 181 if (type_len == 0) return (NDEF_MSG_LENGTH_MISMATCH); 182 } 183 184 /* External type and Well Known types should have valid characters 185 in the TYPE field */ 186 if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_EXT || 187 (rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_WKT) { 188 uint8_t* p_rec_type = p_rec; 189 if ((p_rec_type + type_len) > p_end) return (NDEF_MSG_TOO_SHORT); 190 191 for (int type_index = 0; type_index < type_len; type_index++) { 192 if (p_rec_type[type_index] < NDEF_RTD_VALID_START || 193 p_rec_type[type_index] > NDEF_RTD_VALID_END) 194 return (NDEF_MSG_INVALID_TYPE); 195 } 196 } 197 198 /* Point to next record */ 199 p_rec += (payload_len + type_len + id_len); 200 201 if (rec_hdr & NDEF_ME_MASK) break; 202 203 rec_hdr = 0; 204 } 205 206 /* The last record should have the ME bit set */ 207 if ((rec_hdr & NDEF_ME_MASK) == 0) return (NDEF_MSG_NO_MSG_END); 208 209 /* p_rec should equal p_end if all the length fields were correct */ 210 if (p_rec != p_end) return (NDEF_MSG_LENGTH_MISMATCH); 211 212 return (NDEF_OK); 213 } 214 215 /******************************************************************************* 216 ** 217 ** Function NDEF_MsgGetNumRecs 218 ** 219 ** Description This function gets the number of records in the given NDEF 220 ** message. 221 ** 222 ** Returns The record count, or 0 if the message is invalid. 223 ** 224 *******************************************************************************/ 225 int32_t NDEF_MsgGetNumRecs(uint8_t* p_msg) { 226 uint8_t* p_rec = p_msg; 227 uint8_t rec_hdr, type_len, id_len; 228 int count; 229 uint32_t payload_len; 230 231 for (count = 0;;) { 232 count++; 233 234 rec_hdr = *p_rec++; 235 236 if (rec_hdr & NDEF_ME_MASK) break; 237 238 /* Type field length */ 239 type_len = *p_rec++; 240 241 /* Payload length - can be 1 or 4 bytes */ 242 if (rec_hdr & NDEF_SR_MASK) 243 payload_len = *p_rec++; 244 else 245 BE_STREAM_TO_UINT32(payload_len, p_rec); 246 247 /* ID field Length */ 248 if (rec_hdr & NDEF_IL_MASK) 249 id_len = *p_rec++; 250 else 251 id_len = 0; 252 253 /* Point to next record */ 254 p_rec += (payload_len + type_len + id_len); 255 } 256 257 /* Return the number of records found */ 258 return (count); 259 } 260 261 /******************************************************************************* 262 ** 263 ** Function NDEF_MsgGetRecLength 264 ** 265 ** Description This function returns length of the current record in the 266 ** given NDEF message. 267 ** 268 ** Returns Length of record 269 ** 270 *******************************************************************************/ 271 uint32_t NDEF_MsgGetRecLength(uint8_t* p_cur_rec) { 272 uint8_t rec_hdr, type_len, id_len; 273 uint32_t rec_len = 0; 274 uint32_t payload_len; 275 276 /* Get the current record's header */ 277 rec_hdr = *p_cur_rec++; 278 rec_len++; 279 280 /* Type field length */ 281 type_len = *p_cur_rec++; 282 rec_len++; 283 284 /* Payload length - can be 1 or 4 bytes */ 285 if (rec_hdr & NDEF_SR_MASK) { 286 payload_len = *p_cur_rec++; 287 rec_len++; 288 } else { 289 BE_STREAM_TO_UINT32(payload_len, p_cur_rec); 290 rec_len += 4; 291 } 292 293 /* ID field Length */ 294 if (rec_hdr & NDEF_IL_MASK) { 295 id_len = *p_cur_rec++; 296 rec_len++; 297 } else 298 id_len = 0; 299 300 /* Total length of record */ 301 rec_len += (payload_len + type_len + id_len); 302 303 return (rec_len); 304 } 305 306 /******************************************************************************* 307 ** 308 ** Function NDEF_MsgGetNextRec 309 ** 310 ** Description This function gets a pointer to the next record in the given 311 ** NDEF message. If the current record pointer is NULL, a 312 ** pointer to the first record is returned. 313 ** 314 ** Returns Pointer to the start of the record, or NULL if no more 315 ** 316 *******************************************************************************/ 317 uint8_t* NDEF_MsgGetNextRec(uint8_t* p_cur_rec) { 318 uint8_t rec_hdr, type_len, id_len; 319 uint32_t payload_len; 320 321 /* Get the current record's header */ 322 rec_hdr = *p_cur_rec++; 323 324 /* If this is the last record, return NULL */ 325 if (rec_hdr & NDEF_ME_MASK) return (NULL); 326 327 /* Type field length */ 328 type_len = *p_cur_rec++; 329 330 /* Payload length - can be 1 or 4 bytes */ 331 if (rec_hdr & NDEF_SR_MASK) 332 payload_len = *p_cur_rec++; 333 else 334 BE_STREAM_TO_UINT32(payload_len, p_cur_rec); 335 336 /* ID field Length */ 337 if (rec_hdr & NDEF_IL_MASK) 338 id_len = *p_cur_rec++; 339 else 340 id_len = 0; 341 342 /* Point to next record */ 343 p_cur_rec += (payload_len + type_len + id_len); 344 345 return (p_cur_rec); 346 } 347 348 /******************************************************************************* 349 ** 350 ** Function NDEF_MsgGetRecByIndex 351 ** 352 ** Description This function gets a pointer to the record with the given 353 ** index (0-based index) in the given NDEF message. 354 ** 355 ** Returns Pointer to the start of the record, or NULL 356 ** 357 *******************************************************************************/ 358 uint8_t* NDEF_MsgGetRecByIndex(uint8_t* p_msg, int32_t index) { 359 uint8_t* p_rec = p_msg; 360 uint8_t rec_hdr, type_len, id_len; 361 int32_t count; 362 uint32_t payload_len; 363 364 for (count = 0;; count++) { 365 if (count == index) return (p_rec); 366 367 rec_hdr = *p_rec++; 368 369 if (rec_hdr & NDEF_ME_MASK) return (NULL); 370 371 /* Type field length */ 372 type_len = *p_rec++; 373 374 /* Payload length - can be 1 or 4 bytes */ 375 if (rec_hdr & NDEF_SR_MASK) 376 payload_len = *p_rec++; 377 else 378 BE_STREAM_TO_UINT32(payload_len, p_rec); 379 380 /* ID field Length */ 381 if (rec_hdr & NDEF_IL_MASK) 382 id_len = *p_rec++; 383 else 384 id_len = 0; 385 386 /* Point to next record */ 387 p_rec += (payload_len + type_len + id_len); 388 } 389 390 /* If here, there is no record of that index */ 391 return (NULL); 392 } 393 394 /******************************************************************************* 395 ** 396 ** Function NDEF_MsgGetLastRecInMsg 397 ** 398 ** Description This function gets a pointer to the last record in the 399 ** given NDEF message. 400 ** 401 ** Returns Pointer to the start of the last record, or NULL if some 402 ** problem 403 ** 404 *******************************************************************************/ 405 uint8_t* NDEF_MsgGetLastRecInMsg(uint8_t* p_msg) { 406 uint8_t* p_rec = p_msg; 407 uint8_t* pRecStart; 408 uint8_t rec_hdr, type_len, id_len; 409 uint32_t payload_len; 410 411 for (;;) { 412 pRecStart = p_rec; 413 rec_hdr = *p_rec++; 414 415 if (rec_hdr & NDEF_ME_MASK) break; 416 417 /* Type field length */ 418 type_len = *p_rec++; 419 420 /* Payload length - can be 1 or 4 bytes */ 421 if (rec_hdr & NDEF_SR_MASK) 422 payload_len = *p_rec++; 423 else 424 BE_STREAM_TO_UINT32(payload_len, p_rec); 425 426 /* ID field Length */ 427 if (rec_hdr & NDEF_IL_MASK) 428 id_len = *p_rec++; 429 else 430 id_len = 0; 431 432 /* Point to next record */ 433 p_rec += (payload_len + type_len + id_len); 434 } 435 436 return (pRecStart); 437 } 438 439 /******************************************************************************* 440 ** 441 ** Function NDEF_MsgGetFirstRecByType 442 ** 443 ** Description This function gets a pointer to the first record with the 444 ** given record type in the given NDEF message. 445 ** 446 ** Returns Pointer to the start of the record, or NULL 447 ** 448 *******************************************************************************/ 449 uint8_t* NDEF_MsgGetFirstRecByType(uint8_t* p_msg, uint8_t tnf, uint8_t* p_type, 450 uint8_t tlen) { 451 uint8_t* p_rec = p_msg; 452 uint8_t* pRecStart; 453 uint8_t rec_hdr, type_len, id_len; 454 uint32_t payload_len; 455 456 for (;;) { 457 pRecStart = p_rec; 458 459 rec_hdr = *p_rec++; 460 461 /* Type field length */ 462 type_len = *p_rec++; 463 464 /* Payload length - can be 1 or 4 bytes */ 465 if (rec_hdr & NDEF_SR_MASK) 466 payload_len = *p_rec++; 467 else 468 BE_STREAM_TO_UINT32(payload_len, p_rec); 469 470 /* ID field Length */ 471 if (rec_hdr & NDEF_IL_MASK) 472 id_len = *p_rec++; 473 else 474 id_len = 0; 475 476 /* At this point, p_rec points to the start of the type field. We need to */ 477 /* compare the type of the type, the length of the type and the data */ 478 if (((rec_hdr & NDEF_TNF_MASK) == tnf) && (type_len == tlen) && 479 (!memcmp(p_rec, p_type, tlen))) 480 return (pRecStart); 481 482 /* If this was the last record, return NULL */ 483 if (rec_hdr & NDEF_ME_MASK) return (NULL); 484 485 /* Point to next record */ 486 p_rec += (payload_len + type_len + id_len); 487 } 488 489 /* If here, there is no record of that type */ 490 return (NULL); 491 } 492 493 /******************************************************************************* 494 ** 495 ** Function NDEF_MsgGetNextRecByType 496 ** 497 ** Description This function gets a pointer to the next record with the 498 ** given record type in the given NDEF message. 499 ** 500 ** Returns Pointer to the start of the record, or NULL 501 ** 502 *******************************************************************************/ 503 uint8_t* NDEF_MsgGetNextRecByType(uint8_t* p_cur_rec, uint8_t tnf, 504 uint8_t* p_type, uint8_t tlen) { 505 uint8_t* p_rec; 506 uint8_t* pRecStart; 507 uint8_t rec_hdr, type_len, id_len; 508 uint32_t payload_len; 509 510 /* If this is the last record in the message, return NULL */ 511 p_rec = NDEF_MsgGetNextRec(p_cur_rec); 512 if (p_rec == NULL) return (NULL); 513 514 for (;;) { 515 pRecStart = p_rec; 516 517 rec_hdr = *p_rec++; 518 519 /* Type field length */ 520 type_len = *p_rec++; 521 522 /* Payload length - can be 1 or 4 bytes */ 523 if (rec_hdr & NDEF_SR_MASK) 524 payload_len = *p_rec++; 525 else 526 BE_STREAM_TO_UINT32(payload_len, p_rec); 527 528 /* ID field Length */ 529 if (rec_hdr & NDEF_IL_MASK) 530 id_len = *p_rec++; 531 else 532 id_len = 0; 533 534 /* At this point, p_rec points to the start of the type field. We need to */ 535 /* compare the type of the type, the length of the type and the data */ 536 if (((rec_hdr & NDEF_TNF_MASK) == tnf) && (type_len == tlen) && 537 (!memcmp(p_rec, p_type, tlen))) 538 return (pRecStart); 539 540 /* If this was the last record, return NULL */ 541 if (rec_hdr & NDEF_ME_MASK) break; 542 543 /* Point to next record */ 544 p_rec += (payload_len + type_len + id_len); 545 } 546 547 /* If here, there is no record of that type */ 548 return (NULL); 549 } 550 551 /******************************************************************************* 552 ** 553 ** Function NDEF_MsgGetFirstRecById 554 ** 555 ** Description This function gets a pointer to the first record with the 556 ** given record id in the given NDEF message. 557 ** 558 ** Returns Pointer to the start of the record, or NULL 559 ** 560 *******************************************************************************/ 561 uint8_t* NDEF_MsgGetFirstRecById(uint8_t* p_msg, uint8_t* p_id, uint8_t ilen) { 562 uint8_t* p_rec = p_msg; 563 uint8_t* pRecStart; 564 uint8_t rec_hdr, type_len, id_len; 565 uint32_t payload_len; 566 567 for (;;) { 568 pRecStart = p_rec; 569 570 rec_hdr = *p_rec++; 571 572 /* Type field length */ 573 type_len = *p_rec++; 574 575 /* Payload length - can be 1 or 4 bytes */ 576 if (rec_hdr & NDEF_SR_MASK) 577 payload_len = *p_rec++; 578 else 579 BE_STREAM_TO_UINT32(payload_len, p_rec); 580 581 /* ID field Length */ 582 if (rec_hdr & NDEF_IL_MASK) 583 id_len = *p_rec++; 584 else 585 id_len = 0; 586 587 /* At this point, p_rec points to the start of the type field. Skip it */ 588 p_rec += type_len; 589 590 /* At this point, p_rec points to the start of the ID field. Compare length 591 * and data */ 592 if ((id_len == ilen) && (!memcmp(p_rec, p_id, ilen))) return (pRecStart); 593 594 /* If this was the last record, return NULL */ 595 if (rec_hdr & NDEF_ME_MASK) return (NULL); 596 597 /* Point to next record */ 598 p_rec += (id_len + payload_len); 599 } 600 601 /* If here, there is no record of that ID */ 602 return (NULL); 603 } 604 605 /******************************************************************************* 606 ** 607 ** Function NDEF_MsgGetNextRecById 608 ** 609 ** Description This function gets a pointer to the next record with the 610 ** given record id in the given NDEF message. 611 ** 612 ** Returns Pointer to the start of the record, or NULL 613 ** 614 *******************************************************************************/ 615 uint8_t* NDEF_MsgGetNextRecById(uint8_t* p_cur_rec, uint8_t* p_id, 616 uint8_t ilen) { 617 uint8_t* p_rec; 618 uint8_t* pRecStart; 619 uint8_t rec_hdr, type_len, id_len; 620 uint32_t payload_len; 621 622 /* If this is the last record in the message, return NULL */ 623 p_rec = NDEF_MsgGetNextRec(p_cur_rec); 624 if (p_rec == NULL) return (NULL); 625 626 for (;;) { 627 pRecStart = p_rec; 628 629 rec_hdr = *p_rec++; 630 631 /* Type field length */ 632 type_len = *p_rec++; 633 634 /* Payload length - can be 1 or 4 bytes */ 635 if (rec_hdr & NDEF_SR_MASK) 636 payload_len = *p_rec++; 637 else 638 BE_STREAM_TO_UINT32(payload_len, p_rec); 639 640 /* ID field Length */ 641 if (rec_hdr & NDEF_IL_MASK) 642 id_len = *p_rec++; 643 else 644 id_len = 0; 645 646 /* At this point, p_rec points to the start of the type field. Skip it */ 647 p_rec += type_len; 648 649 /* At this point, p_rec points to the start of the ID field. Compare length 650 * and data */ 651 if ((id_len == ilen) && (!memcmp(p_rec, p_id, ilen))) return (pRecStart); 652 653 /* If this was the last record, return NULL */ 654 if (rec_hdr & NDEF_ME_MASK) break; 655 656 /* Point to next record */ 657 p_rec += (id_len + payload_len); 658 } 659 660 /* If here, there is no record of that ID */ 661 return (NULL); 662 } 663 664 /******************************************************************************* 665 ** 666 ** Function NDEF_RecGetType 667 ** 668 ** Description This function gets a pointer to the record type for the 669 ** given NDEF record. 670 ** 671 ** Returns Pointer to Type (NULL if none). TNF and len are filled in. 672 ** 673 *******************************************************************************/ 674 uint8_t* NDEF_RecGetType(uint8_t* p_rec, uint8_t* p_tnf, uint8_t* p_type_len) { 675 uint8_t rec_hdr, type_len; 676 677 /* First byte is the record header */ 678 rec_hdr = *p_rec++; 679 680 /* Next byte is the type field length */ 681 type_len = *p_rec++; 682 683 /* Skip the payload length */ 684 if (rec_hdr & NDEF_SR_MASK) 685 p_rec += 1; 686 else 687 p_rec += 4; 688 689 /* Skip ID field Length, if present */ 690 if (rec_hdr & NDEF_IL_MASK) p_rec++; 691 692 /* At this point, p_rec points to the start of the type field. */ 693 *p_type_len = type_len; 694 *p_tnf = rec_hdr & NDEF_TNF_MASK; 695 696 if (type_len == 0) 697 return (NULL); 698 else 699 return (p_rec); 700 } 701 702 /******************************************************************************* 703 ** 704 ** Function NDEF_RecGetId 705 ** 706 ** Description This function gets a pointer to the record id for the given 707 ** NDEF record. 708 ** 709 ** Returns Pointer to Id (NULL if none). ID Len is filled in. 710 ** 711 *******************************************************************************/ 712 uint8_t* NDEF_RecGetId(uint8_t* p_rec, uint8_t* p_id_len) { 713 uint8_t rec_hdr, type_len; 714 715 /* First byte is the record header */ 716 rec_hdr = *p_rec++; 717 718 /* Next byte is the type field length */ 719 type_len = *p_rec++; 720 721 /* Skip the payload length */ 722 if (rec_hdr & NDEF_SR_MASK) 723 p_rec++; 724 else 725 p_rec += 4; 726 727 /* ID field Length */ 728 if (rec_hdr & NDEF_IL_MASK) 729 *p_id_len = *p_rec++; 730 else 731 *p_id_len = 0; 732 733 /* p_rec now points to the start of the type field. The ID field follows it */ 734 if (*p_id_len == 0) 735 return (NULL); 736 else 737 return (p_rec + type_len); 738 } 739 740 /******************************************************************************* 741 ** 742 ** Function NDEF_RecGetPayload 743 ** 744 ** Description This function gets a pointer to the payload for the given 745 ** NDEF record. 746 ** 747 ** Returns a pointer to the payload (or NULL none). Payload len filled 748 ** in. 749 ** 750 *******************************************************************************/ 751 uint8_t* NDEF_RecGetPayload(uint8_t* p_rec, uint32_t* p_payload_len) { 752 uint8_t rec_hdr, type_len, id_len; 753 uint32_t payload_len; 754 755 /* First byte is the record header */ 756 rec_hdr = *p_rec++; 757 758 /* Next byte is the type field length */ 759 type_len = *p_rec++; 760 761 /* Next is the payload length (1 or 4 bytes) */ 762 if (rec_hdr & NDEF_SR_MASK) 763 payload_len = *p_rec++; 764 else 765 BE_STREAM_TO_UINT32(payload_len, p_rec); 766 767 *p_payload_len = payload_len; 768 769 /* ID field Length */ 770 if (rec_hdr & NDEF_IL_MASK) 771 id_len = *p_rec++; 772 else 773 id_len = 0; 774 775 /* p_rec now points to the start of the type field. The ID field follows it, 776 * then the payload */ 777 if (payload_len == 0) 778 return (NULL); 779 else 780 return (p_rec + type_len + id_len); 781 } 782 783 /******************************************************************************* 784 ** 785 ** Function NDEF_MsgInit 786 ** 787 ** Description This function initializes an NDEF message. 788 ** 789 ** Returns void 790 ** *p_cur_size is initialized to 0 791 ** 792 *******************************************************************************/ 793 void NDEF_MsgInit(uint8_t* p_msg, uint32_t max_size, uint32_t* p_cur_size) { 794 *p_cur_size = 0; 795 memset(p_msg, 0, max_size); 796 } 797 798 /******************************************************************************* 799 ** 800 ** Function NDEF_MsgAddRec 801 ** 802 ** Description This function adds an NDEF record to the end of an NDEF 803 ** message. 804 ** 805 ** Returns OK, or error if the record did not fit 806 ** *p_cur_size is updated 807 ** 808 *******************************************************************************/ 809 extern tNDEF_STATUS NDEF_MsgAddRec(uint8_t* p_msg, uint32_t max_size, 810 uint32_t* p_cur_size, uint8_t tnf, 811 uint8_t* p_type, uint8_t type_len, 812 uint8_t* p_id, uint8_t id_len, 813 uint8_t* p_payload, uint32_t payload_len) { 814 uint8_t* p_rec = p_msg + *p_cur_size; 815 uint32_t recSize; 816 int plen = (payload_len < 256) ? 1 : 4; 817 int ilen = (id_len == 0) ? 0 : 1; 818 819 if (tnf > NDEF_TNF_RESERVED) { 820 tnf = NDEF_TNF_UNKNOWN; 821 type_len = 0; 822 } 823 824 /* First, make sure the record will fit. we need at least 2 bytes for header 825 * and type length */ 826 recSize = payload_len + 2 + type_len + plen + ilen + id_len; 827 828 if ((*p_cur_size + recSize) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); 829 830 /* Construct the record header. For the first record, set both begin and end 831 * bits */ 832 if (*p_cur_size == 0) 833 *p_rec = tnf | NDEF_MB_MASK | NDEF_ME_MASK; 834 else { 835 /* Find the previous last and clear his 'Message End' bit */ 836 uint8_t* pLast = NDEF_MsgGetLastRecInMsg(p_msg); 837 838 if (!pLast) return (NDEF_MSG_NO_MSG_END); 839 840 *pLast &= ~NDEF_ME_MASK; 841 *p_rec = tnf | NDEF_ME_MASK; 842 } 843 844 if (plen == 1) *p_rec |= NDEF_SR_MASK; 845 846 if (ilen != 0) *p_rec |= NDEF_IL_MASK; 847 848 p_rec++; 849 850 /* The next byte is the type field length */ 851 *p_rec++ = type_len; 852 853 /* Payload length - can be 1 or 4 bytes */ 854 if (plen == 1) 855 *p_rec++ = (uint8_t)payload_len; 856 else 857 UINT32_TO_BE_STREAM(p_rec, payload_len); 858 859 /* ID field Length (optional) */ 860 if (ilen > 0) *p_rec++ = id_len; 861 862 /* Next comes the type */ 863 if (type_len) { 864 if (p_type) memcpy(p_rec, p_type, type_len); 865 866 p_rec += type_len; 867 } 868 869 /* Next comes the ID */ 870 if (id_len) { 871 if (p_id) memcpy(p_rec, p_id, id_len); 872 873 p_rec += id_len; 874 } 875 876 /* And lastly the payload. If NULL, the app just wants to reserve memory */ 877 if (p_payload) memcpy(p_rec, p_payload, payload_len); 878 879 *p_cur_size += recSize; 880 881 return (NDEF_OK); 882 } 883 884 /******************************************************************************* 885 ** 886 ** Function NDEF_MsgInsertRec 887 ** 888 ** Description This function inserts a record at a specific index into the 889 ** given NDEF message 890 ** 891 ** Returns OK, or error if the record did not fit 892 ** *p_cur_size is updated 893 ** 894 *******************************************************************************/ 895 extern tNDEF_STATUS NDEF_MsgInsertRec(uint8_t* p_msg, uint32_t max_size, 896 uint32_t* p_cur_size, int32_t index, 897 uint8_t tnf, uint8_t* p_type, 898 uint8_t type_len, uint8_t* p_id, 899 uint8_t id_len, uint8_t* p_payload, 900 uint32_t payload_len) { 901 uint8_t* p_rec; 902 uint32_t recSize; 903 int32_t plen = (payload_len < 256) ? 1 : 4; 904 int32_t ilen = (id_len == 0) ? 0 : 1; 905 906 /* First, make sure the record will fit. we need at least 2 bytes for header 907 * and type length */ 908 recSize = payload_len + 2 + type_len + plen + ilen + id_len; 909 910 if ((*p_cur_size + recSize) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); 911 912 /* See where the new record goes. If at the end, call the 'AddRec' function */ 913 if ((index >= NDEF_MsgGetNumRecs(p_msg)) || 914 ((p_rec = NDEF_MsgGetRecByIndex(p_msg, index)) == NULL)) { 915 return NDEF_MsgAddRec(p_msg, max_size, p_cur_size, tnf, p_type, type_len, 916 p_id, id_len, p_payload, payload_len); 917 } 918 919 /* If we are inserting at the beginning, remove the MB bit from the current 920 * first */ 921 if (index == 0) *p_msg &= ~NDEF_MB_MASK; 922 923 /* Make space for the new record */ 924 shiftdown(p_rec, (uint32_t)(*p_cur_size - (p_rec - p_msg)), recSize); 925 926 /* If adding at the beginning, set begin bit */ 927 if (index == 0) 928 *p_rec = tnf | NDEF_MB_MASK; 929 else 930 *p_rec = tnf; 931 932 if (plen == 1) *p_rec |= NDEF_SR_MASK; 933 934 if (ilen != 0) *p_rec |= NDEF_IL_MASK; 935 936 p_rec++; 937 938 /* The next byte is the type field length */ 939 *p_rec++ = type_len; 940 941 /* Payload length - can be 1 or 4 bytes */ 942 if (plen == 1) 943 *p_rec++ = (uint8_t)payload_len; 944 else 945 UINT32_TO_BE_STREAM(p_rec, payload_len); 946 947 /* ID field Length (optional) */ 948 if (ilen != 0) *p_rec++ = id_len; 949 950 /* Next comes the type */ 951 if (type_len) { 952 if (p_type) memcpy(p_rec, p_type, type_len); 953 954 p_rec += type_len; 955 } 956 957 /* Next comes the ID */ 958 if (ilen != 0) { 959 if (p_id) memcpy(p_rec, p_id, id_len); 960 961 p_rec += id_len; 962 } 963 964 /* And lastly the payload. If NULL, the app just wants to reserve memory */ 965 if (p_payload) memcpy(p_rec, p_payload, payload_len); 966 967 *p_cur_size += recSize; 968 969 return (NDEF_OK); 970 } 971 972 /******************************************************************************* 973 ** 974 ** Function NDEF_MsgAppendRec 975 ** 976 ** Description This function adds NDEF records to the end of an NDEF 977 ** message. 978 ** 979 ** Returns OK, or error if the record did not fit 980 ** *p_cur_size is updated 981 ** 982 *******************************************************************************/ 983 extern tNDEF_STATUS NDEF_MsgAppendRec(uint8_t* p_msg, uint32_t max_size, 984 uint32_t* p_cur_size, uint8_t* p_new_rec, 985 uint32_t new_rec_len) { 986 uint8_t* p_rec; 987 tNDEF_STATUS status; 988 989 /* First, validate new records */ 990 status = NDEF_MsgValidate(p_new_rec, new_rec_len, false); 991 if (status != NDEF_OK) return (status); 992 993 /* First, make sure the record will fit */ 994 if ((*p_cur_size + new_rec_len) > max_size) 995 return (NDEF_MSG_INSUFFICIENT_MEM); 996 997 /* Find where to copy new record */ 998 if (*p_cur_size == 0) 999 p_rec = p_msg; 1000 else { 1001 /* Find the previous last and clear his 'Message End' bit */ 1002 uint8_t* pLast = NDEF_MsgGetLastRecInMsg(p_msg); 1003 1004 if (!pLast) return (NDEF_MSG_NO_MSG_END); 1005 1006 *pLast &= ~NDEF_ME_MASK; 1007 p_rec = p_msg + *p_cur_size; 1008 1009 /* clear 'Message Begin' bit of new record */ 1010 *p_new_rec &= ~NDEF_MB_MASK; 1011 } 1012 1013 /* append new records */ 1014 memcpy(p_rec, p_new_rec, new_rec_len); 1015 1016 *p_cur_size += new_rec_len; 1017 1018 return (NDEF_OK); 1019 } 1020 1021 /******************************************************************************* 1022 ** 1023 ** Function NDEF_MsgAppendPayload 1024 ** 1025 ** Description This function appends extra payload to a specific record in 1026 ** the given NDEF message 1027 ** 1028 ** Returns OK, or error if the extra payload did not fit 1029 ** *p_cur_size is updated 1030 ** 1031 *******************************************************************************/ 1032 tNDEF_STATUS NDEF_MsgAppendPayload(uint8_t* p_msg, uint32_t max_size, 1033 uint32_t* p_cur_size, uint8_t* p_rec, 1034 uint8_t* p_add_pl, uint32_t add_pl_len) { 1035 uint32_t prev_paylen, new_paylen; 1036 uint8_t *p_prev_pl, *pp; 1037 uint8_t incr_lenfld = 0; 1038 uint8_t type_len, id_len; 1039 1040 /* Skip header */ 1041 pp = p_rec + 1; 1042 1043 /* Next byte is the type field length */ 1044 type_len = *pp++; 1045 1046 /* Next is the payload length (1 or 4 bytes) */ 1047 if (*p_rec & NDEF_SR_MASK) 1048 prev_paylen = *pp++; 1049 else 1050 BE_STREAM_TO_UINT32(prev_paylen, pp); 1051 1052 /* ID field Length */ 1053 if (*p_rec & NDEF_IL_MASK) 1054 id_len = *pp++; 1055 else 1056 id_len = 0; 1057 1058 p_prev_pl = pp + type_len + id_len; 1059 1060 new_paylen = prev_paylen + add_pl_len; 1061 1062 /* Previous payload may be < 256, and this addition may make it larger than 1063 * 256 */ 1064 /* If that were to happen, the payload length field goes from 1 byte to 4 1065 * bytes */ 1066 if ((prev_paylen < 256) && (new_paylen > 255)) incr_lenfld = 3; 1067 1068 /* Check that it all fits */ 1069 if ((*p_cur_size + add_pl_len + incr_lenfld) > max_size) 1070 return (NDEF_MSG_INSUFFICIENT_MEM); 1071 1072 /* Point to payload length field */ 1073 pp = p_rec + 2; 1074 1075 /* If we need to increase the length field from 1 to 4 bytes, do it first */ 1076 if (incr_lenfld) { 1077 shiftdown(pp + 1, (uint32_t)(*p_cur_size - (pp - p_msg) - 1), 3); 1078 p_prev_pl += 3; 1079 } 1080 1081 /* Store in the new length */ 1082 if (new_paylen > 255) { 1083 *p_rec &= ~NDEF_SR_MASK; 1084 UINT32_TO_BE_STREAM(pp, new_paylen); 1085 } else 1086 *pp = (uint8_t)new_paylen; 1087 1088 /* Point to the end of the previous payload */ 1089 pp = p_prev_pl + prev_paylen; 1090 1091 /* If we are not the last record, make space for the extra payload */ 1092 if ((*p_rec & NDEF_ME_MASK) == 0) 1093 shiftdown(pp, (uint32_t)(*p_cur_size - (pp - p_msg)), add_pl_len); 1094 1095 /* Now copy in the additional payload data */ 1096 memcpy(pp, p_add_pl, add_pl_len); 1097 1098 *p_cur_size += add_pl_len + incr_lenfld; 1099 1100 return (NDEF_OK); 1101 } 1102 1103 /******************************************************************************* 1104 ** 1105 ** Function NDEF_MsgReplacePayload 1106 ** 1107 ** Description This function replaces the payload of a specific record in 1108 ** the given NDEF message 1109 ** 1110 ** Returns OK, or error if the new payload did not fit 1111 ** *p_cur_size is updated 1112 ** 1113 *******************************************************************************/ 1114 tNDEF_STATUS NDEF_MsgReplacePayload(uint8_t* p_msg, uint32_t max_size, 1115 uint32_t* p_cur_size, uint8_t* p_rec, 1116 uint8_t* p_new_pl, uint32_t new_pl_len) { 1117 uint32_t prev_paylen; 1118 uint8_t *p_prev_pl, *pp; 1119 uint32_t paylen_delta; 1120 uint8_t type_len, id_len; 1121 1122 /* Skip header */ 1123 pp = p_rec + 1; 1124 1125 /* Next byte is the type field length */ 1126 type_len = *pp++; 1127 1128 /* Next is the payload length (1 or 4 bytes) */ 1129 if (*p_rec & NDEF_SR_MASK) 1130 prev_paylen = *pp++; 1131 else 1132 BE_STREAM_TO_UINT32(prev_paylen, pp); 1133 1134 /* ID field Length */ 1135 if (*p_rec & NDEF_IL_MASK) 1136 id_len = *pp++; 1137 else 1138 id_len = 0; 1139 1140 p_prev_pl = pp + type_len + id_len; 1141 1142 /* Point to payload length field again */ 1143 pp = p_rec + 2; 1144 1145 if (new_pl_len > prev_paylen) { 1146 /* New payload is larger than the previous */ 1147 paylen_delta = new_pl_len - prev_paylen; 1148 1149 /* If the previous payload length was < 256, and new is > 255 */ 1150 /* the payload length field goes from 1 byte to 4 bytes */ 1151 if ((prev_paylen < 256) && (new_pl_len > 255)) { 1152 if ((*p_cur_size + paylen_delta + 3) > max_size) 1153 return (NDEF_MSG_INSUFFICIENT_MEM); 1154 1155 shiftdown(pp + 1, (uint32_t)(*p_cur_size - (pp - p_msg) - 1), 3); 1156 p_prev_pl += 3; 1157 *p_cur_size += 3; 1158 *p_rec &= ~NDEF_SR_MASK; 1159 } else if ((*p_cur_size + paylen_delta) > max_size) 1160 return (NDEF_MSG_INSUFFICIENT_MEM); 1161 1162 /* Store in the new length */ 1163 if (new_pl_len > 255) { 1164 UINT32_TO_BE_STREAM(pp, new_pl_len); 1165 } else 1166 *pp = (uint8_t)new_pl_len; 1167 1168 /* Point to the end of the previous payload */ 1169 pp = p_prev_pl + prev_paylen; 1170 1171 /* If we are not the last record, make space for the extra payload */ 1172 if ((*p_rec & NDEF_ME_MASK) == 0) 1173 shiftdown(pp, (uint32_t)(*p_cur_size - (pp - p_msg)), paylen_delta); 1174 1175 *p_cur_size += paylen_delta; 1176 } else if (new_pl_len < prev_paylen) { 1177 /* New payload is smaller than the previous */ 1178 paylen_delta = prev_paylen - new_pl_len; 1179 1180 /* If the previous payload was > 256, and new is less than 256 */ 1181 /* the payload length field goes from 4 bytes to 1 byte */ 1182 if ((prev_paylen > 255) && (new_pl_len < 256)) { 1183 shiftup(pp + 1, pp + 4, (uint32_t)(*p_cur_size - (pp - p_msg) - 3)); 1184 p_prev_pl -= 3; 1185 *p_cur_size -= 3; 1186 *p_rec |= NDEF_SR_MASK; 1187 } 1188 1189 /* Store in the new length */ 1190 if (new_pl_len > 255) { 1191 UINT32_TO_BE_STREAM(pp, new_pl_len); 1192 } else 1193 *pp = (uint8_t)new_pl_len; 1194 1195 /* Point to the end of the previous payload */ 1196 pp = p_prev_pl + prev_paylen; 1197 1198 /* If we are not the last record, remove the extra space from the previous 1199 * payload */ 1200 if ((*p_rec & NDEF_ME_MASK) == 0) 1201 shiftup(pp - paylen_delta, pp, (uint32_t)(*p_cur_size - (pp - p_msg))); 1202 1203 *p_cur_size -= paylen_delta; 1204 } 1205 1206 /* Now copy in the new payload data */ 1207 if (p_new_pl) memcpy(p_prev_pl, p_new_pl, new_pl_len); 1208 1209 return (NDEF_OK); 1210 } 1211 1212 /******************************************************************************* 1213 ** 1214 ** Function NDEF_MsgReplaceType 1215 ** 1216 ** Description This function replaces the type field of a specific record 1217 ** in the given NDEF message 1218 ** 1219 ** Returns OK, or error if the new type field did not fit 1220 ** *p_cur_size is updated 1221 ** 1222 *******************************************************************************/ 1223 tNDEF_STATUS NDEF_MsgReplaceType(uint8_t* p_msg, uint32_t max_size, 1224 uint32_t* p_cur_size, uint8_t* p_rec, 1225 uint8_t* p_new_type, uint8_t new_type_len) { 1226 uint8_t typelen_delta; 1227 uint8_t *p_prev_type, prev_type_len; 1228 uint8_t* pp; 1229 1230 /* Skip header */ 1231 pp = p_rec + 1; 1232 1233 /* Next byte is the type field length */ 1234 prev_type_len = *pp++; 1235 1236 /* Skip the payload length */ 1237 if (*p_rec & NDEF_SR_MASK) 1238 pp += 1; 1239 else 1240 pp += 4; 1241 1242 if (*p_rec & NDEF_IL_MASK) pp++; 1243 1244 /* Save pointer to the start of the type field */ 1245 p_prev_type = pp; 1246 1247 if (new_type_len > prev_type_len) { 1248 /* New type is larger than the previous */ 1249 typelen_delta = new_type_len - prev_type_len; 1250 1251 if ((*p_cur_size + typelen_delta) > max_size) 1252 return (NDEF_MSG_INSUFFICIENT_MEM); 1253 1254 /* Point to the end of the previous type, and make space for the extra data 1255 */ 1256 pp = p_prev_type + prev_type_len; 1257 shiftdown(pp, (uint32_t)(*p_cur_size - (pp - p_msg)), typelen_delta); 1258 1259 *p_cur_size += typelen_delta; 1260 } else if (new_type_len < prev_type_len) { 1261 /* New type field is smaller than the previous */ 1262 typelen_delta = prev_type_len - new_type_len; 1263 1264 /* Point to the end of the previous type, and shift up to fill the the 1265 * unused space */ 1266 pp = p_prev_type + prev_type_len; 1267 shiftup(pp - typelen_delta, pp, (uint32_t)(*p_cur_size - (pp - p_msg))); 1268 1269 *p_cur_size -= typelen_delta; 1270 } 1271 1272 /* Save in new type length */ 1273 p_rec[1] = new_type_len; 1274 1275 /* Now copy in the new type field data */ 1276 if (p_new_type) memcpy(p_prev_type, p_new_type, new_type_len); 1277 1278 return (NDEF_OK); 1279 } 1280 1281 /******************************************************************************* 1282 ** 1283 ** Function NDEF_MsgReplaceId 1284 ** 1285 ** Description This function replaces the ID field of a specific record in 1286 ** the given NDEF message 1287 ** 1288 ** Returns OK, or error if the new ID field did not fit 1289 ** *p_cur_size is updated 1290 ** 1291 *******************************************************************************/ 1292 tNDEF_STATUS NDEF_MsgReplaceId(uint8_t* p_msg, uint32_t max_size, 1293 uint32_t* p_cur_size, uint8_t* p_rec, 1294 uint8_t* p_new_id, uint8_t new_id_len) { 1295 uint8_t idlen_delta; 1296 uint8_t *p_prev_id, *p_idlen_field; 1297 uint8_t prev_id_len, type_len; 1298 uint8_t* pp; 1299 1300 /* Skip header */ 1301 pp = p_rec + 1; 1302 1303 /* Next byte is the type field length */ 1304 type_len = *pp++; 1305 1306 /* Skip the payload length */ 1307 if (*p_rec & NDEF_SR_MASK) 1308 pp += 1; 1309 else 1310 pp += 4; 1311 1312 p_idlen_field = pp; 1313 1314 if (*p_rec & NDEF_IL_MASK) 1315 prev_id_len = *pp++; 1316 else 1317 prev_id_len = 0; 1318 1319 /* Save pointer to the start of the ID field (right after the type field) */ 1320 p_prev_id = pp + type_len; 1321 1322 if (new_id_len > prev_id_len) { 1323 /* New ID field is larger than the previous */ 1324 idlen_delta = new_id_len - prev_id_len; 1325 1326 /* If the previous ID length was 0, we need to add a 1-byte ID length */ 1327 if (prev_id_len == 0) { 1328 if ((*p_cur_size + idlen_delta + 1) > max_size) 1329 return (NDEF_MSG_INSUFFICIENT_MEM); 1330 1331 shiftdown(p_idlen_field, 1332 (uint32_t)(*p_cur_size - (p_idlen_field - p_msg)), 1); 1333 p_prev_id += 1; 1334 *p_cur_size += 1; 1335 *p_rec |= NDEF_IL_MASK; 1336 } else if ((*p_cur_size + idlen_delta) > max_size) 1337 return (NDEF_MSG_INSUFFICIENT_MEM); 1338 1339 /* Point to the end of the previous ID field, and make space for the extra 1340 * data */ 1341 pp = p_prev_id + prev_id_len; 1342 shiftdown(pp, (uint32_t)(*p_cur_size - (pp - p_msg)), idlen_delta); 1343 1344 *p_cur_size += idlen_delta; 1345 } else if (new_id_len < prev_id_len) { 1346 /* New ID field is smaller than the previous */ 1347 idlen_delta = prev_id_len - new_id_len; 1348 1349 /* Point to the end of the previous ID, and shift up to fill the the unused 1350 * space */ 1351 pp = p_prev_id + prev_id_len; 1352 shiftup(pp - idlen_delta, pp, (uint32_t)(*p_cur_size - (pp - p_msg))); 1353 1354 *p_cur_size -= idlen_delta; 1355 1356 /* If removing the ID, make sure that length field is also removed */ 1357 if (new_id_len == 0) { 1358 shiftup(p_idlen_field, p_idlen_field + 1, 1359 (uint32_t)(*p_cur_size - (p_idlen_field - p_msg - (uint32_t)1))); 1360 *p_rec &= ~NDEF_IL_MASK; 1361 *p_cur_size -= 1; 1362 } 1363 } 1364 1365 /* Save in new ID length and data */ 1366 if (new_id_len) { 1367 *p_idlen_field = new_id_len; 1368 1369 if (p_new_id) memcpy(p_prev_id, p_new_id, new_id_len); 1370 } 1371 1372 return (NDEF_OK); 1373 } 1374 1375 /******************************************************************************* 1376 ** 1377 ** Function NDEF_MsgRemoveRec 1378 ** 1379 ** Description This function removes the record at the given 1380 ** index in the given NDEF message. 1381 ** 1382 ** Returns TRUE if OK, FALSE if the index was invalid 1383 ** *p_cur_size is updated 1384 ** 1385 *******************************************************************************/ 1386 tNDEF_STATUS NDEF_MsgRemoveRec(uint8_t* p_msg, uint32_t* p_cur_size, 1387 int32_t index) { 1388 uint8_t* p_rec = NDEF_MsgGetRecByIndex(p_msg, index); 1389 uint8_t *pNext, *pPrev; 1390 1391 if (!p_rec) return (NDEF_REC_NOT_FOUND); 1392 1393 /* If this is the first record in the message... */ 1394 if (*p_rec & NDEF_MB_MASK) { 1395 /* Find the second record (if any) and set his 'Message Begin' bit */ 1396 pNext = NDEF_MsgGetRecByIndex(p_msg, 1); 1397 if (pNext != NULL) { 1398 *pNext |= NDEF_MB_MASK; 1399 1400 *p_cur_size -= (uint32_t)(pNext - p_msg); 1401 1402 shiftup(p_msg, pNext, *p_cur_size); 1403 } else 1404 *p_cur_size = 0; /* No more records, lenght must be zero */ 1405 1406 return (NDEF_OK); 1407 } 1408 1409 /* If this is the last record in the message... */ 1410 if (*p_rec & NDEF_ME_MASK) { 1411 if (index > 0) { 1412 /* Find the previous record and set his 'Message End' bit */ 1413 pPrev = NDEF_MsgGetRecByIndex(p_msg, index - 1); 1414 if (pPrev == NULL) return false; 1415 1416 *pPrev |= NDEF_ME_MASK; 1417 } 1418 *p_cur_size = (uint32_t)(p_rec - p_msg); 1419 1420 return (NDEF_OK); 1421 } 1422 1423 /* Not the first or the last... get the address of the next record */ 1424 pNext = NDEF_MsgGetNextRec(p_rec); 1425 if (pNext == NULL) return false; 1426 1427 /* We are removing p_rec, so shift from pNext to the end */ 1428 shiftup(p_rec, pNext, (uint32_t)(*p_cur_size - (pNext - p_msg))); 1429 1430 *p_cur_size -= (uint32_t)(pNext - p_rec); 1431 1432 return (NDEF_OK); 1433 } 1434 1435 /******************************************************************************* 1436 ** 1437 ** Function NDEF_MsgCopyAndDechunk 1438 ** 1439 ** Description This function copies and de-chunks an NDEF message. 1440 ** It is assumed that the destination is at least as large 1441 ** as the source, since the source may not actually contain 1442 ** any chunks. 1443 ** 1444 ** Returns The output byte count 1445 ** 1446 *******************************************************************************/ 1447 tNDEF_STATUS NDEF_MsgCopyAndDechunk(uint8_t* p_src, uint32_t src_len, 1448 uint8_t* p_dest, uint32_t* p_out_len) { 1449 uint32_t out_len, max_out_len; 1450 uint8_t* p_rec; 1451 uint8_t* p_prev_rec = p_dest; 1452 uint8_t *p_type, *p_id, *p_pay; 1453 uint8_t type_len, id_len, tnf; 1454 uint32_t pay_len; 1455 tNDEF_STATUS status; 1456 1457 /* First, validate the source */ 1458 status = NDEF_MsgValidate(p_src, src_len, true); 1459 if (status != NDEF_OK) return (status); 1460 1461 /* The output buffer must be at least as large as the input buffer */ 1462 max_out_len = src_len; 1463 1464 /* Initialize output */ 1465 NDEF_MsgInit(p_dest, max_out_len, &out_len); 1466 1467 p_rec = p_src; 1468 1469 /* Now, copy record by record */ 1470 while ((p_rec != NULL) && (status == NDEF_OK)) { 1471 p_type = NDEF_RecGetType(p_rec, &tnf, &type_len); 1472 p_id = NDEF_RecGetId(p_rec, &id_len); 1473 p_pay = NDEF_RecGetPayload(p_rec, &pay_len); 1474 1475 /* If this is the continuation of a chunk, append the payload to the 1476 * previous */ 1477 if (tnf == NDEF_TNF_UNCHANGED) { 1478 if (p_pay) { 1479 status = NDEF_MsgAppendPayload(p_dest, max_out_len, &out_len, 1480 p_prev_rec, p_pay, pay_len); 1481 } 1482 } else { 1483 p_prev_rec = p_dest + out_len; 1484 1485 status = NDEF_MsgAddRec(p_dest, max_out_len, &out_len, tnf, p_type, 1486 type_len, p_id, id_len, p_pay, pay_len); 1487 } 1488 1489 p_rec = NDEF_MsgGetNextRec(p_rec); 1490 } 1491 1492 *p_out_len = out_len; 1493 1494 return (status); 1495 } 1496
