/****************************************************************************** * * Copyright (C) 2010-2014 Broadcom Corporation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * ******************************************************************************/ /****************************************************************************** * * This file contains source code for some utility functions to help parse * and build NFC Data Exchange Format (NDEF) messages * ******************************************************************************/ #include <string.h> #include "ndef_utils.h" /******************************************************************************* ** ** Static Local Functions ** *******************************************************************************/ /******************************************************************************* ** ** Function shiftdown ** ** Description shift memory down (to make space to insert a record) ** *******************************************************************************/ static void shiftdown (UINT8 *p_mem, UINT32 len, UINT32 shift_amount) { register UINT8 *ps = p_mem + len - 1; register UINT8 *pd = ps + shift_amount; register UINT32 xx; for (xx = 0; xx < len; xx++) *pd-- = *ps--; } /******************************************************************************* ** ** Function shiftup ** ** Description shift memory up (to delete a record) ** *******************************************************************************/ static void shiftup (UINT8 *p_dest, UINT8 *p_src, UINT32 len) { register UINT8 *ps = p_src; register UINT8 *pd = p_dest; register UINT32 xx; for (xx = 0; xx < len; xx++) *pd++ = *ps++; } /******************************************************************************* ** ** Function NDEF_MsgValidate ** ** Description This function validates an NDEF message. ** ** Returns TRUE if all OK, or FALSE if the message is invalid. ** *******************************************************************************/ tNDEF_STATUS NDEF_MsgValidate (UINT8 *p_msg, UINT32 msg_len, BOOLEAN b_allow_chunks) { UINT8 *p_rec = p_msg; UINT8 *p_end = p_msg + msg_len; UINT8 rec_hdr=0, type_len, id_len; int count; UINT32 payload_len; BOOLEAN bInChunk = FALSE; if ( (p_msg == NULL) || (msg_len < 3) ) return (NDEF_MSG_TOO_SHORT); /* The first record must have the MB bit set */ if ((*p_msg & NDEF_MB_MASK) == 0) return (NDEF_MSG_NO_MSG_BEGIN); /* The first record cannot be a chunk */ if ((*p_msg & NDEF_TNF_MASK) == NDEF_TNF_UNCHANGED) return (NDEF_MSG_UNEXPECTED_CHUNK); for (count = 0; p_rec < p_end; count++) { /* if less than short record header */ if (p_rec + 3 > p_end) return (NDEF_MSG_TOO_SHORT); rec_hdr = *p_rec++; /* The second and all subsequent records must NOT have the MB bit set */ if ( (count > 0) && (rec_hdr & NDEF_MB_MASK) ) return (NDEF_MSG_EXTRA_MSG_BEGIN); /* Type field length */ type_len = *p_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else { /* if less than 4 bytes payload length */ if (p_rec + 4 > p_end) return (NDEF_MSG_TOO_SHORT); BE_STREAM_TO_UINT32 (payload_len, p_rec); } /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) { /* if less than 1 byte ID field length */ if (p_rec + 1 > p_end) return (NDEF_MSG_TOO_SHORT); id_len = *p_rec++; } else id_len = 0; /* A chunk must have type "unchanged", and no type or ID fields */ if (rec_hdr & NDEF_CF_MASK) { if (!b_allow_chunks) return (NDEF_MSG_UNEXPECTED_CHUNK); /* Inside a chunk, the type must be unchanged and no type or ID field i sallowed */ if (bInChunk) { if ( (type_len != 0) || (id_len != 0) || ((rec_hdr & NDEF_TNF_MASK) != NDEF_TNF_UNCHANGED) ) return (NDEF_MSG_INVALID_CHUNK); } else { /* First record of a chunk must NOT have type "unchanged" */ if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_UNCHANGED) return (NDEF_MSG_INVALID_CHUNK); bInChunk = TRUE; } } else { /* This may be the last guy in a chunk. */ if (bInChunk) { if ( (type_len != 0) || (id_len != 0) || ((rec_hdr & NDEF_TNF_MASK) != NDEF_TNF_UNCHANGED) ) return (NDEF_MSG_INVALID_CHUNK); bInChunk = FALSE; } else { /* If not in a chunk, the record must NOT have type "unchanged" */ if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_UNCHANGED) return (NDEF_MSG_INVALID_CHUNK); } } /* An empty record must NOT have a type, ID or payload */ if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_EMPTY) { if ( (type_len != 0) || (id_len != 0) || (payload_len != 0) ) return (NDEF_MSG_INVALID_EMPTY_REC); } if ((rec_hdr & NDEF_TNF_MASK) == NDEF_TNF_UNKNOWN) { if (type_len != 0) return (NDEF_MSG_LENGTH_MISMATCH); } /* Point to next record */ p_rec += (payload_len + type_len + id_len); if (rec_hdr & NDEF_ME_MASK) break; rec_hdr = 0; } /* The last record should have the ME bit set */ if ((rec_hdr & NDEF_ME_MASK) == 0) return (NDEF_MSG_NO_MSG_END); /* p_rec should equal p_end if all the length fields were correct */ if (p_rec != p_end) return (NDEF_MSG_LENGTH_MISMATCH); return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgGetNumRecs ** ** Description This function gets the number of records in the given NDEF ** message. ** ** Returns The record count, or 0 if the message is invalid. ** *******************************************************************************/ INT32 NDEF_MsgGetNumRecs (UINT8 *p_msg) { UINT8 *p_rec = p_msg; UINT8 rec_hdr, type_len, id_len; int count; UINT32 payload_len; for (count = 0; ; ) { count++; rec_hdr = *p_rec++; if (rec_hdr & NDEF_ME_MASK) break; /* Type field length */ type_len = *p_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_rec); /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_rec++; else id_len = 0; /* Point to next record */ p_rec += (payload_len + type_len + id_len); } /* Return the number of records found */ return (count); } /******************************************************************************* ** ** Function NDEF_MsgGetRecLength ** ** Description This function returns length of the current record in the given ** NDEF message. ** ** Returns Length of record ** *******************************************************************************/ UINT32 NDEF_MsgGetRecLength (UINT8 *p_cur_rec) { UINT8 rec_hdr, type_len, id_len; UINT32 rec_len = 0; UINT32 payload_len; /* Get the current record's header */ rec_hdr = *p_cur_rec++; rec_len++; /* Type field length */ type_len = *p_cur_rec++; rec_len++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) { payload_len = *p_cur_rec++; rec_len++; } else { BE_STREAM_TO_UINT32 (payload_len, p_cur_rec); rec_len += 4; } /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) { id_len = *p_cur_rec++; rec_len++; } else id_len = 0; /* Total length of record */ rec_len += (payload_len + type_len + id_len); return (rec_len); } /******************************************************************************* ** ** Function NDEF_MsgGetNextRec ** ** Description This function gets a pointer to the next record in the given ** NDEF message. If the current record pointer is NULL, a pointer ** to the first record is returned. ** ** Returns Pointer to the start of the record, or NULL if no more ** *******************************************************************************/ UINT8 *NDEF_MsgGetNextRec (UINT8 *p_cur_rec) { UINT8 rec_hdr, type_len, id_len; UINT32 payload_len; /* Get the current record's header */ rec_hdr = *p_cur_rec++; /* If this is the last record, return NULL */ if (rec_hdr & NDEF_ME_MASK) return (NULL); /* Type field length */ type_len = *p_cur_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_cur_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_cur_rec); /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_cur_rec++; else id_len = 0; /* Point to next record */ p_cur_rec += (payload_len + type_len + id_len); return (p_cur_rec); } /******************************************************************************* ** ** Function NDEF_MsgGetRecByIndex ** ** Description This function gets a pointer to the record with the given ** index (0-based index) in the given NDEF message. ** ** Returns Pointer to the start of the record, or NULL ** *******************************************************************************/ UINT8 *NDEF_MsgGetRecByIndex (UINT8 *p_msg, INT32 index) { UINT8 *p_rec = p_msg; UINT8 rec_hdr, type_len, id_len; INT32 count; UINT32 payload_len; for (count = 0; ; count++) { if (count == index) return (p_rec); rec_hdr = *p_rec++; if (rec_hdr & NDEF_ME_MASK) return (NULL); /* Type field length */ type_len = *p_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_rec); /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_rec++; else id_len = 0; /* Point to next record */ p_rec += (payload_len + type_len + id_len); } /* If here, there is no record of that index */ return (NULL); } /******************************************************************************* ** ** Function NDEF_MsgGetLastRecInMsg ** ** Description This function gets a pointer to the last record in the ** given NDEF message. ** ** Returns Pointer to the start of the last record, or NULL if some problem ** *******************************************************************************/ UINT8 *NDEF_MsgGetLastRecInMsg (UINT8 *p_msg) { UINT8 *p_rec = p_msg; UINT8 *pRecStart; UINT8 rec_hdr, type_len, id_len; UINT32 payload_len; for ( ; ; ) { pRecStart = p_rec; rec_hdr = *p_rec++; if (rec_hdr & NDEF_ME_MASK) break; /* Type field length */ type_len = *p_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_rec); /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_rec++; else id_len = 0; /* Point to next record */ p_rec += (payload_len + type_len + id_len); } return (pRecStart); } /******************************************************************************* ** ** Function NDEF_MsgGetFirstRecByType ** ** Description This function gets a pointer to the first record with the given ** record type in the given NDEF message. ** ** Returns Pointer to the start of the record, or NULL ** *******************************************************************************/ UINT8 *NDEF_MsgGetFirstRecByType (UINT8 *p_msg, UINT8 tnf, UINT8 *p_type, UINT8 tlen) { UINT8 *p_rec = p_msg; UINT8 *pRecStart; UINT8 rec_hdr, type_len, id_len; UINT32 payload_len; for ( ; ; ) { pRecStart = p_rec; rec_hdr = *p_rec++; /* Type field length */ type_len = *p_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_rec); /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_rec++; else id_len = 0; /* At this point, p_rec points to the start of the type field. We need to */ /* compare the type of the type, the length of the type and the data */ if ( ((rec_hdr & NDEF_TNF_MASK) == tnf) && (type_len == tlen) && (!memcmp (p_rec, p_type, tlen)) ) return (pRecStart); /* If this was the last record, return NULL */ if (rec_hdr & NDEF_ME_MASK) return (NULL); /* Point to next record */ p_rec += (payload_len + type_len + id_len); } /* If here, there is no record of that type */ return (NULL); } /******************************************************************************* ** ** Function NDEF_MsgGetNextRecByType ** ** Description This function gets a pointer to the next record with the given ** record type in the given NDEF message. ** ** Returns Pointer to the start of the record, or NULL ** *******************************************************************************/ UINT8 *NDEF_MsgGetNextRecByType (UINT8 *p_cur_rec, UINT8 tnf, UINT8 *p_type, UINT8 tlen) { UINT8 *p_rec; UINT8 *pRecStart; UINT8 rec_hdr, type_len, id_len; UINT32 payload_len; /* If this is the last record in the message, return NULL */ if ((p_rec = NDEF_MsgGetNextRec (p_cur_rec)) == NULL) return (NULL); for ( ; ; ) { pRecStart = p_rec; rec_hdr = *p_rec++; /* Type field length */ type_len = *p_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_rec); /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_rec++; else id_len = 0; /* At this point, p_rec points to the start of the type field. We need to */ /* compare the type of the type, the length of the type and the data */ if ( ((rec_hdr & NDEF_TNF_MASK) == tnf) && (type_len == tlen) && (!memcmp (p_rec, p_type, tlen)) ) return (pRecStart); /* If this was the last record, return NULL */ if (rec_hdr & NDEF_ME_MASK) break; /* Point to next record */ p_rec += (payload_len + type_len + id_len); } /* If here, there is no record of that type */ return (NULL); } /******************************************************************************* ** ** Function NDEF_MsgGetFirstRecById ** ** Description This function gets a pointer to the first record with the given ** record id in the given NDEF message. ** ** Returns Pointer to the start of the record, or NULL ** *******************************************************************************/ UINT8 *NDEF_MsgGetFirstRecById (UINT8 *p_msg, UINT8 *p_id, UINT8 ilen) { UINT8 *p_rec = p_msg; UINT8 *pRecStart; UINT8 rec_hdr, type_len, id_len; UINT32 payload_len; for ( ; ; ) { pRecStart = p_rec; rec_hdr = *p_rec++; /* Type field length */ type_len = *p_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_rec); /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_rec++; else id_len = 0; /* At this point, p_rec points to the start of the type field. Skip it */ p_rec += type_len; /* At this point, p_rec points to the start of the ID field. Compare length and data */ if ( (id_len == ilen) && (!memcmp (p_rec, p_id, ilen)) ) return (pRecStart); /* If this was the last record, return NULL */ if (rec_hdr & NDEF_ME_MASK) return (NULL); /* Point to next record */ p_rec += (id_len + payload_len); } /* If here, there is no record of that ID */ return (NULL); } /******************************************************************************* ** ** Function NDEF_MsgGetNextRecById ** ** Description This function gets a pointer to the next record with the given ** record id in the given NDEF message. ** ** Returns Pointer to the start of the record, or NULL ** *******************************************************************************/ UINT8 *NDEF_MsgGetNextRecById (UINT8 *p_cur_rec, UINT8 *p_id, UINT8 ilen) { UINT8 *p_rec; UINT8 *pRecStart; UINT8 rec_hdr, type_len, id_len; UINT32 payload_len; /* If this is the last record in the message, return NULL */ if ((p_rec = NDEF_MsgGetNextRec (p_cur_rec)) == NULL) return (NULL); for ( ; ; ) { pRecStart = p_rec; rec_hdr = *p_rec++; /* Type field length */ type_len = *p_rec++; /* Payload length - can be 1 or 4 bytes */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_rec); /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_rec++; else id_len = 0; /* At this point, p_rec points to the start of the type field. Skip it */ p_rec += type_len; /* At this point, p_rec points to the start of the ID field. Compare length and data */ if ( (id_len == ilen) && (!memcmp (p_rec, p_id, ilen)) ) return (pRecStart); /* If this was the last record, return NULL */ if (rec_hdr & NDEF_ME_MASK) break; /* Point to next record */ p_rec += (id_len + payload_len); } /* If here, there is no record of that ID */ return (NULL); } /******************************************************************************* ** ** Function NDEF_RecGetType ** ** Description This function gets a pointer to the record type for the given NDEF record. ** ** Returns Pointer to Type (NULL if none). TNF and len are filled in. ** *******************************************************************************/ UINT8 *NDEF_RecGetType (UINT8 *p_rec, UINT8 *p_tnf, UINT8 *p_type_len) { UINT8 rec_hdr, type_len; /* First byte is the record header */ rec_hdr = *p_rec++; /* Next byte is the type field length */ type_len = *p_rec++; /* Skip the payload length */ if (rec_hdr & NDEF_SR_MASK) p_rec += 1; else p_rec += 4; /* Skip ID field Length, if present */ if (rec_hdr & NDEF_IL_MASK) p_rec++; /* At this point, p_rec points to the start of the type field. */ *p_type_len = type_len; *p_tnf = rec_hdr & NDEF_TNF_MASK; if (type_len == 0) return (NULL); else return (p_rec); } /******************************************************************************* ** ** Function NDEF_RecGetId ** ** Description This function gets a pointer to the record id for the given NDEF record. ** ** Returns Pointer to Id (NULL if none). ID Len is filled in. ** *******************************************************************************/ UINT8 *NDEF_RecGetId (UINT8 *p_rec, UINT8 *p_id_len) { UINT8 rec_hdr, type_len; /* First byte is the record header */ rec_hdr = *p_rec++; /* Next byte is the type field length */ type_len = *p_rec++; /* Skip the payload length */ if (rec_hdr & NDEF_SR_MASK) p_rec++; else p_rec += 4; /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) *p_id_len = *p_rec++; else *p_id_len = 0; /* p_rec now points to the start of the type field. The ID field follows it */ if (*p_id_len == 0) return (NULL); else return (p_rec + type_len); } /******************************************************************************* ** ** Function NDEF_RecGetPayload ** ** Description This function gets a pointer to the payload for the given NDEF record. ** ** Returns a pointer to the payload (or NULL none). Payload len filled in. ** *******************************************************************************/ UINT8 *NDEF_RecGetPayload (UINT8 *p_rec, UINT32 *p_payload_len) { UINT8 rec_hdr, type_len, id_len; UINT32 payload_len; /* First byte is the record header */ rec_hdr = *p_rec++; /* Next byte is the type field length */ type_len = *p_rec++; /* Next is the payload length (1 or 4 bytes) */ if (rec_hdr & NDEF_SR_MASK) payload_len = *p_rec++; else BE_STREAM_TO_UINT32 (payload_len, p_rec); *p_payload_len = payload_len; /* ID field Length */ if (rec_hdr & NDEF_IL_MASK) id_len = *p_rec++; else id_len = 0; /* p_rec now points to the start of the type field. The ID field follows it, then the payload */ if (payload_len == 0) return (NULL); else return (p_rec + type_len + id_len); } /******************************************************************************* ** ** Function NDEF_MsgInit ** ** Description This function initializes an NDEF message. ** ** Returns void ** *p_cur_size is initialized to 0 ** *******************************************************************************/ void NDEF_MsgInit (UINT8 *p_msg, UINT32 max_size, UINT32 *p_cur_size) { *p_cur_size = 0; memset (p_msg, 0, max_size); } /******************************************************************************* ** ** Function NDEF_MsgAddRec ** ** Description This function adds an NDEF record to the end of an NDEF message. ** ** Returns OK, or error if the record did not fit ** *p_cur_size is updated ** *******************************************************************************/ extern tNDEF_STATUS NDEF_MsgAddRec (UINT8 *p_msg, UINT32 max_size, UINT32 *p_cur_size, UINT8 tnf, UINT8 *p_type, UINT8 type_len, UINT8 *p_id, UINT8 id_len, UINT8 *p_payload, UINT32 payload_len) { UINT8 *p_rec = p_msg + *p_cur_size; UINT32 recSize; int plen = (payload_len < 256) ? 1 : 4; int ilen = (id_len == 0) ? 0 : 1; if (tnf > NDEF_TNF_RESERVED) { tnf = NDEF_TNF_UNKNOWN; type_len = 0; } /* First, make sure the record will fit. we need at least 2 bytes for header and type length */ recSize = payload_len + 2 + type_len + plen + ilen + id_len; if ((*p_cur_size + recSize) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); /* Construct the record header. For the first record, set both begin and end bits */ if (*p_cur_size == 0) *p_rec = tnf | NDEF_MB_MASK | NDEF_ME_MASK; else { /* Find the previous last and clear his 'Message End' bit */ UINT8 *pLast = NDEF_MsgGetLastRecInMsg (p_msg); if (!pLast) return (NDEF_MSG_NO_MSG_END); *pLast &= ~NDEF_ME_MASK; *p_rec = tnf | NDEF_ME_MASK; } if (plen == 1) *p_rec |= NDEF_SR_MASK; if (ilen != 0) *p_rec |= NDEF_IL_MASK; p_rec++; /* The next byte is the type field length */ *p_rec++ = type_len; /* Payload length - can be 1 or 4 bytes */ if (plen == 1) *p_rec++ = (UINT8)payload_len; else UINT32_TO_BE_STREAM (p_rec, payload_len); /* ID field Length (optional) */ if (ilen > 0) *p_rec++ = id_len; /* Next comes the type */ if (type_len) { if (p_type) memcpy (p_rec, p_type, type_len); p_rec += type_len; } /* Next comes the ID */ if (id_len) { if (p_id) memcpy (p_rec, p_id, id_len); p_rec += id_len; } /* And lastly the payload. If NULL, the app just wants to reserve memory */ if (p_payload) memcpy (p_rec, p_payload, payload_len); *p_cur_size += recSize; return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgInsertRec ** ** Description This function inserts a record at a specific index into the ** given NDEF message ** ** Returns OK, or error if the record did not fit ** *p_cur_size is updated ** *******************************************************************************/ extern tNDEF_STATUS NDEF_MsgInsertRec (UINT8 *p_msg, UINT32 max_size, UINT32 *p_cur_size, INT32 index, UINT8 tnf, UINT8 *p_type, UINT8 type_len, UINT8 *p_id, UINT8 id_len, UINT8 *p_payload, UINT32 payload_len) { UINT8 *p_rec; UINT32 recSize; INT32 plen = (payload_len < 256) ? 1 : 4; INT32 ilen = (id_len == 0) ? 0 : 1; /* First, make sure the record will fit. we need at least 2 bytes for header and type length */ recSize = payload_len + 2 + type_len + plen + ilen + id_len; if ((*p_cur_size + recSize) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); /* See where the new record goes. If at the end, call the 'AddRec' function */ if ( (index >= NDEF_MsgGetNumRecs (p_msg)) || ((p_rec = NDEF_MsgGetRecByIndex(p_msg, index)) == NULL) ) { return NDEF_MsgAddRec (p_msg, max_size, p_cur_size, tnf, p_type, type_len, p_id, id_len, p_payload, payload_len); } /* If we are inserting at the beginning, remove the MB bit from the current first */ if (index == 0) *p_msg &= ~NDEF_MB_MASK; /* Make space for the new record */ shiftdown (p_rec, (UINT32)(*p_cur_size - (p_rec - p_msg)), recSize); /* If adding at the beginning, set begin bit */ if (index == 0) *p_rec = tnf | NDEF_MB_MASK; else *p_rec = tnf; if (plen == 1) *p_rec |= NDEF_SR_MASK; if (ilen != 0) *p_rec |= NDEF_IL_MASK; p_rec++; /* The next byte is the type field length */ *p_rec++ = type_len; /* Payload length - can be 1 or 4 bytes */ if (plen == 1) *p_rec++ = (UINT8)payload_len; else UINT32_TO_BE_STREAM (p_rec, payload_len); /* ID field Length (optional) */ if (ilen != 0) *p_rec++ = id_len; /* Next comes the type */ if (type_len) { if (p_type) memcpy (p_rec, p_type, type_len); p_rec += type_len; } /* Next comes the ID */ if (ilen != 0) { if (p_id) memcpy (p_rec, p_id, id_len); p_rec += id_len; } /* And lastly the payload. If NULL, the app just wants to reserve memory */ if (p_payload) memcpy (p_rec, p_payload, payload_len); *p_cur_size += recSize; return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgAppendRec ** ** Description This function adds NDEF records to the end of an NDEF message. ** ** Returns OK, or error if the record did not fit ** *p_cur_size is updated ** *******************************************************************************/ extern tNDEF_STATUS NDEF_MsgAppendRec (UINT8 *p_msg, UINT32 max_size, UINT32 *p_cur_size, UINT8 *p_new_rec, UINT32 new_rec_len) { UINT8 *p_rec; tNDEF_STATUS status; /* First, validate new records */ if ((status = NDEF_MsgValidate(p_new_rec, new_rec_len, FALSE)) != NDEF_OK) return (status); /* First, make sure the record will fit */ if ((*p_cur_size + new_rec_len) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); /* Find where to copy new record */ if (*p_cur_size == 0) p_rec = p_msg; else { /* Find the previous last and clear his 'Message End' bit */ UINT8 *pLast = NDEF_MsgGetLastRecInMsg (p_msg); if (!pLast) return (NDEF_MSG_NO_MSG_END); *pLast &= ~NDEF_ME_MASK; p_rec = p_msg + *p_cur_size; /* clear 'Message Begin' bit of new record */ *p_new_rec &= ~NDEF_MB_MASK; } /* append new records */ memcpy (p_rec, p_new_rec, new_rec_len); *p_cur_size += new_rec_len; return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgAppendPayload ** ** Description This function appends extra payload to a specific record in the ** given NDEF message ** ** Returns OK, or error if the extra payload did not fit ** *p_cur_size is updated ** *******************************************************************************/ tNDEF_STATUS NDEF_MsgAppendPayload (UINT8 *p_msg, UINT32 max_size, UINT32 *p_cur_size, UINT8 *p_rec, UINT8 *p_add_pl, UINT32 add_pl_len) { UINT32 prev_paylen, new_paylen; UINT8 *p_prev_pl, *pp; UINT8 incr_lenfld = 0; UINT8 type_len, id_len; /* Skip header */ pp = p_rec + 1; /* Next byte is the type field length */ type_len = *pp++; /* Next is the payload length (1 or 4 bytes) */ if (*p_rec & NDEF_SR_MASK) prev_paylen = *pp++; else BE_STREAM_TO_UINT32 (prev_paylen, pp); /* ID field Length */ if (*p_rec & NDEF_IL_MASK) id_len = *pp++; else id_len = 0; p_prev_pl = pp + type_len + id_len; new_paylen = prev_paylen + add_pl_len; /* Previous payload may be < 256, and this addition may make it larger than 256 */ /* If that were to happen, the payload length field goes from 1 byte to 4 bytes */ if ( (prev_paylen < 256) && (new_paylen > 255) ) incr_lenfld = 3; /* Check that it all fits */ if ((*p_cur_size + add_pl_len + incr_lenfld) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); /* Point to payload length field */ pp = p_rec + 2; /* If we need to increase the length field from 1 to 4 bytes, do it first */ if (incr_lenfld) { shiftdown (pp + 1, (UINT32)(*p_cur_size - (pp - p_msg) - 1), 3); p_prev_pl += 3; } /* Store in the new length */ if (new_paylen > 255) { *p_rec &= ~NDEF_SR_MASK; UINT32_TO_BE_STREAM (pp, new_paylen); } else *pp = (UINT8)new_paylen; /* Point to the end of the previous payload */ pp = p_prev_pl + prev_paylen; /* If we are not the last record, make space for the extra payload */ if ((*p_rec & NDEF_ME_MASK) == 0) shiftdown (pp, (UINT32)(*p_cur_size - (pp - p_msg)), add_pl_len); /* Now copy in the additional payload data */ memcpy (pp, p_add_pl, add_pl_len); *p_cur_size += add_pl_len + incr_lenfld; return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgReplacePayload ** ** Description This function replaces the payload of a specific record in the ** given NDEF message ** ** Returns OK, or error if the new payload did not fit ** *p_cur_size is updated ** *******************************************************************************/ tNDEF_STATUS NDEF_MsgReplacePayload (UINT8 *p_msg, UINT32 max_size, UINT32 *p_cur_size, UINT8 *p_rec, UINT8 *p_new_pl, UINT32 new_pl_len) { UINT32 prev_paylen; UINT8 *p_prev_pl, *pp; UINT32 paylen_delta; UINT8 type_len, id_len; /* Skip header */ pp = p_rec + 1; /* Next byte is the type field length */ type_len = *pp++; /* Next is the payload length (1 or 4 bytes) */ if (*p_rec & NDEF_SR_MASK) prev_paylen = *pp++; else BE_STREAM_TO_UINT32 (prev_paylen, pp); /* ID field Length */ if (*p_rec & NDEF_IL_MASK) id_len = *pp++; else id_len = 0; p_prev_pl = pp + type_len + id_len; /* Point to payload length field again */ pp = p_rec + 2; if (new_pl_len > prev_paylen) { /* New payload is larger than the previous */ paylen_delta = new_pl_len - prev_paylen; /* If the previous payload length was < 256, and new is > 255 */ /* the payload length field goes from 1 byte to 4 bytes */ if ( (prev_paylen < 256) && (new_pl_len > 255) ) { if ((*p_cur_size + paylen_delta + 3) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); shiftdown (pp + 1, (UINT32)(*p_cur_size - (pp - p_msg) - 1), 3); p_prev_pl += 3; *p_cur_size += 3; *p_rec &= ~NDEF_SR_MASK; } else if ((*p_cur_size + paylen_delta) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); /* Store in the new length */ if (new_pl_len > 255) { UINT32_TO_BE_STREAM (pp, new_pl_len); } else *pp = (UINT8)new_pl_len; /* Point to the end of the previous payload */ pp = p_prev_pl + prev_paylen; /* If we are not the last record, make space for the extra payload */ if ((*p_rec & NDEF_ME_MASK) == 0) shiftdown (pp, (UINT32)(*p_cur_size - (pp - p_msg)), paylen_delta); *p_cur_size += paylen_delta; } else if (new_pl_len < prev_paylen) { /* New payload is smaller than the previous */ paylen_delta = prev_paylen - new_pl_len; /* If the previous payload was > 256, and new is less than 256 */ /* the payload length field goes from 4 bytes to 1 byte */ if ( (prev_paylen > 255) && (new_pl_len < 256) ) { shiftup (pp + 1, pp + 4, (UINT32)(*p_cur_size - (pp - p_msg) - 3)); p_prev_pl -= 3; *p_cur_size -= 3; *p_rec |= NDEF_SR_MASK; } /* Store in the new length */ if (new_pl_len > 255) { UINT32_TO_BE_STREAM (pp, new_pl_len); } else *pp = (UINT8)new_pl_len; /* Point to the end of the previous payload */ pp = p_prev_pl + prev_paylen; /* If we are not the last record, remove the extra space from the previous payload */ if ((*p_rec & NDEF_ME_MASK) == 0) shiftup (pp - paylen_delta, pp, (UINT32)(*p_cur_size - (pp - p_msg))); *p_cur_size -= paylen_delta; } /* Now copy in the new payload data */ if (p_new_pl) memcpy (p_prev_pl, p_new_pl, new_pl_len); return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgReplaceType ** ** Description This function replaces the type field of a specific record in the ** given NDEF message ** ** Returns OK, or error if the new type field did not fit ** *p_cur_size is updated ** *******************************************************************************/ tNDEF_STATUS NDEF_MsgReplaceType (UINT8 *p_msg, UINT32 max_size, UINT32 *p_cur_size, UINT8 *p_rec, UINT8 *p_new_type, UINT8 new_type_len) { UINT8 typelen_delta; UINT8 *p_prev_type, prev_type_len; UINT8 *pp; /* Skip header */ pp = p_rec + 1; /* Next byte is the type field length */ prev_type_len = *pp++; /* Skip the payload length */ if (*p_rec & NDEF_SR_MASK) pp += 1; else pp += 4; if (*p_rec & NDEF_IL_MASK) pp++; /* Save pointer to the start of the type field */ p_prev_type = pp; if (new_type_len > prev_type_len) { /* New type is larger than the previous */ typelen_delta = new_type_len - prev_type_len; if ((*p_cur_size + typelen_delta) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); /* Point to the end of the previous type, and make space for the extra data */ pp = p_prev_type + prev_type_len; shiftdown (pp, (UINT32)(*p_cur_size - (pp - p_msg)), typelen_delta); *p_cur_size += typelen_delta; } else if (new_type_len < prev_type_len) { /* New type field is smaller than the previous */ typelen_delta = prev_type_len - new_type_len; /* Point to the end of the previous type, and shift up to fill the the unused space */ pp = p_prev_type + prev_type_len; shiftup (pp - typelen_delta, pp, (UINT32)(*p_cur_size - (pp - p_msg))); *p_cur_size -= typelen_delta; } /* Save in new type length */ p_rec[1] = new_type_len; /* Now copy in the new type field data */ if (p_new_type) memcpy (p_prev_type, p_new_type, new_type_len); return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgReplaceId ** ** Description This function replaces the ID field of a specific record in the ** given NDEF message ** ** Returns OK, or error if the new ID field did not fit ** *p_cur_size is updated ** *******************************************************************************/ tNDEF_STATUS NDEF_MsgReplaceId (UINT8 *p_msg, UINT32 max_size, UINT32 *p_cur_size, UINT8 *p_rec, UINT8 *p_new_id, UINT8 new_id_len) { UINT8 idlen_delta; UINT8 *p_prev_id, *p_idlen_field; UINT8 prev_id_len, type_len; UINT8 *pp; /* Skip header */ pp = p_rec + 1; /* Next byte is the type field length */ type_len = *pp++; /* Skip the payload length */ if (*p_rec & NDEF_SR_MASK) pp += 1; else pp += 4; p_idlen_field = pp; if (*p_rec & NDEF_IL_MASK) prev_id_len = *pp++; else prev_id_len = 0; /* Save pointer to the start of the ID field (right after the type field) */ p_prev_id = pp + type_len; if (new_id_len > prev_id_len) { /* New ID field is larger than the previous */ idlen_delta = new_id_len - prev_id_len; /* If the previous ID length was 0, we need to add a 1-byte ID length */ if (prev_id_len == 0) { if ((*p_cur_size + idlen_delta + 1) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); shiftdown (p_idlen_field, (UINT32)(*p_cur_size - (p_idlen_field - p_msg)), 1); p_prev_id += 1; *p_cur_size += 1; *p_rec |= NDEF_IL_MASK; } else if ((*p_cur_size + idlen_delta) > max_size) return (NDEF_MSG_INSUFFICIENT_MEM); /* Point to the end of the previous ID field, and make space for the extra data */ pp = p_prev_id + prev_id_len; shiftdown (pp, (UINT32)(*p_cur_size - (pp - p_msg)), idlen_delta); *p_cur_size += idlen_delta; } else if (new_id_len < prev_id_len) { /* New ID field is smaller than the previous */ idlen_delta = prev_id_len - new_id_len; /* Point to the end of the previous ID, and shift up to fill the the unused space */ pp = p_prev_id + prev_id_len; shiftup (pp - idlen_delta, pp, (UINT32)(*p_cur_size - (pp - p_msg))); *p_cur_size -= idlen_delta; /* If removing the ID, make sure that length field is also removed */ if (new_id_len == 0) { shiftup (p_idlen_field, p_idlen_field + 1, (UINT32)(*p_cur_size - (p_idlen_field - p_msg - (UINT32)1))); *p_rec &= ~NDEF_IL_MASK; *p_cur_size -= 1; } } /* Save in new ID length and data */ if (new_id_len) { *p_idlen_field = new_id_len; if (p_new_id) memcpy (p_prev_id, p_new_id, new_id_len); } return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgRemoveRec ** ** Description This function removes the record at the given ** index in the given NDEF message. ** ** Returns TRUE if OK, FALSE if the index was invalid ** *p_cur_size is updated ** *******************************************************************************/ tNDEF_STATUS NDEF_MsgRemoveRec (UINT8 *p_msg, UINT32 *p_cur_size, INT32 index) { UINT8 *p_rec = NDEF_MsgGetRecByIndex (p_msg, index); UINT8 *pNext, *pPrev; if (!p_rec) return (NDEF_REC_NOT_FOUND); /* If this is the first record in the message... */ if (*p_rec & NDEF_MB_MASK) { /* Find the second record (if any) and set his 'Message Begin' bit */ if ((pNext = NDEF_MsgGetRecByIndex(p_msg, 1)) != NULL) { *pNext |= NDEF_MB_MASK; *p_cur_size -= (UINT32)(pNext - p_msg); shiftup (p_msg, pNext, *p_cur_size); } else *p_cur_size = 0; /* No more records, lenght must be zero */ return (NDEF_OK); } /* If this is the last record in the message... */ if (*p_rec & NDEF_ME_MASK) { if (index > 0) { /* Find the previous record and set his 'Message End' bit */ if ((pPrev = NDEF_MsgGetRecByIndex(p_msg, index - 1)) == NULL) return (FALSE); *pPrev |= NDEF_ME_MASK; } *p_cur_size = (UINT32)(p_rec - p_msg); return (NDEF_OK); } /* Not the first or the last... get the address of the next record */ if ((pNext = NDEF_MsgGetNextRec (p_rec)) == NULL) return (FALSE); /* We are removing p_rec, so shift from pNext to the end */ shiftup (p_rec, pNext, (UINT32)(*p_cur_size - (pNext - p_msg))); *p_cur_size -= (UINT32)(pNext - p_rec); return (NDEF_OK); } /******************************************************************************* ** ** Function NDEF_MsgCopyAndDechunk ** ** Description This function copies and de-chunks an NDEF message. ** It is assumed that the destination is at least as large ** as the source, since the source may not actually contain ** any chunks. ** ** Returns The output byte count ** *******************************************************************************/ tNDEF_STATUS NDEF_MsgCopyAndDechunk (UINT8 *p_src, UINT32 src_len, UINT8 *p_dest, UINT32 *p_out_len) { UINT32 out_len, max_out_len; UINT8 *p_rec; UINT8 *p_prev_rec = p_dest; UINT8 *p_type, *p_id, *p_pay; UINT8 type_len, id_len, tnf; UINT32 pay_len; tNDEF_STATUS status; /* First, validate the source */ if ((status = NDEF_MsgValidate(p_src, src_len, TRUE)) != NDEF_OK) return (status); /* The output buffer must be at least as large as the input buffer */ max_out_len = src_len; /* Initialize output */ NDEF_MsgInit (p_dest, max_out_len, &out_len); p_rec = p_src; /* Now, copy record by record */ while ((p_rec != NULL) && (status == NDEF_OK)) { p_type = NDEF_RecGetType (p_rec, &tnf, &type_len); p_id = NDEF_RecGetId (p_rec, &id_len); p_pay = NDEF_RecGetPayload (p_rec, &pay_len); /* If this is the continuation of a chunk, append the payload to the previous */ if (tnf == NDEF_TNF_UNCHANGED) { if (p_pay) { status = NDEF_MsgAppendPayload (p_dest, max_out_len, &out_len, p_prev_rec, p_pay, pay_len); } } else { p_prev_rec = p_dest + out_len; status = NDEF_MsgAddRec (p_dest, max_out_len, &out_len, tnf, p_type, type_len, p_id, id_len, p_pay, pay_len); } p_rec = NDEF_MsgGetNextRec (p_rec); } *p_out_len = out_len; return (status); }