src/nfa/dm/nfa_dm_ndef.cc

/******************************************************************************
 *
 *  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.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  Handle ndef messages
 *
 ******************************************************************************/
#include <string.h>

#include <android-base/stringprintf.h>
#include <base/logging.h>

#include "ndef_utils.h"
#include "nfa_api.h"
#include "nfa_dm_int.h"

using android::base::StringPrintf;

extern bool nfc_debug_enabled;

/*******************************************************************************
* URI Well-known-type prefixes
*******************************************************************************/
const uint8_t* nfa_dm_ndef_wkt_uri_str_tbl[] = {
    nullptr,                                         /* 0x00 */
    (const uint8_t*)"http://www.",                /* 0x01 */
    (const uint8_t*)"https://www.",               /* 0x02 */
    (const uint8_t*)"http://",                    /* 0x03 */
    (const uint8_t*)"https://",                   /* 0x04 */
    (const uint8_t*)"tel:",                       /* 0x05 */
    (const uint8_t*)"mailto:",                    /* 0x06 */
    (const uint8_t*)"ftp://anonymous:anonymous@", /* 0x07 */
    (const uint8_t*)"ftp://ftp.",                 /* 0x08 */
    (const uint8_t*)"ftps://",                    /* 0x09 */
    (const uint8_t*)"sftp://",                    /* 0x0A */
    (const uint8_t*)"smb://",                     /* 0x0B */
    (const uint8_t*)"nfs://",                     /* 0x0C */
    (const uint8_t*)"ftp://",                     /* 0x0D */
    (const uint8_t*)"dav://",                     /* 0x0E */
    (const uint8_t*)"news:",                      /* 0x0F */
    (const uint8_t*)"telnet://",                  /* 0x10 */
    (const uint8_t*)"imap:",                      /* 0x11 */
    (const uint8_t*)"rtsp://",                    /* 0x12 */
    (const uint8_t*)"urn:",                       /* 0x13 */
    (const uint8_t*)"pop:",                       /* 0x14 */
    (const uint8_t*)"sip:",                       /* 0x15 */
    (const uint8_t*)"sips:",                      /* 0x16 */
    (const uint8_t*)"tftp:",                      /* 0x17 */
    (const uint8_t*)"btspp://",                   /* 0x18 */
    (const uint8_t*)"btl2cap://",                 /* 0x19 */
    (const uint8_t*)"btgoep://",                  /* 0x1A */
    (const uint8_t*)"tcpobex://",                 /* 0x1B */
    (const uint8_t*)"irdaobex://",                /* 0x1C */
    (const uint8_t*)"file://",                    /* 0x1D */
    (const uint8_t*)"urn:epc:id:",                /* 0x1E */
    (const uint8_t*)"urn:epc:tag:",               /* 0x1F */
    (const uint8_t*)"urn:epc:pat:",               /* 0x20 */
    (const uint8_t*)"urn:epc:raw:",               /* 0x21 */
    (const uint8_t*)"urn:epc:",                   /* 0x22 */
    (const uint8_t*)"urn:nfc:"                    /* 0x23 */
};
#define NFA_DM_NDEF_WKT_URI_STR_TBL_SIZE \
  (sizeof(nfa_dm_ndef_wkt_uri_str_tbl) / sizeof(uint8_t*))

/*******************************************************************************
**
** Function         nfa_dm_ndef_dereg_hdlr_by_handle
**
** Description      Deregister NDEF record type handler
**
** Returns          TRUE (message buffer to be freed by caller)
**
*******************************************************************************/
void nfa_dm_ndef_dereg_hdlr_by_handle(tNFA_HANDLE ndef_type_handle) {
  tNFA_DM_CB* p_cb = &nfa_dm_cb;
  uint16_t hdlr_idx;
  hdlr_idx = (uint16_t)(ndef_type_handle & NFA_HANDLE_MASK);

  if (p_cb->p_ndef_handler[hdlr_idx]) {
    GKI_freebuf(p_cb->p_ndef_handler[hdlr_idx]);
    p_cb->p_ndef_handler[hdlr_idx] = nullptr;
  }
}

/*******************************************************************************
**
** Function         nfa_dm_ndef_dereg_all
**
** Description      Deregister all NDEF record type handlers (called during
**                  shutdown(.
**
** Returns          Nothing
**
*******************************************************************************/
void nfa_dm_ndef_dereg_all(void) {
  tNFA_DM_CB* p_cb = &nfa_dm_cb;
  uint32_t i;

  for (i = 0; i < NFA_NDEF_MAX_HANDLERS; i++) {
    /* If this is a free slot, then remember it */
    if (p_cb->p_ndef_handler[i] != nullptr) {
      GKI_freebuf(p_cb->p_ndef_handler[i]);
      p_cb->p_ndef_handler[i] = nullptr;
    }
  }
}

/*******************************************************************************
**
** Function         nfa_dm_ndef_reg_hdlr
**
** Description      Register NDEF record type handler
**
** Returns          TRUE if message buffer is to be freed by caller
**
*******************************************************************************/
bool nfa_dm_ndef_reg_hdlr(tNFA_DM_MSG* p_data) {
  tNFA_DM_CB* p_cb = &nfa_dm_cb;
  uint32_t hdlr_idx, i;
  tNFA_DM_API_REG_NDEF_HDLR* p_reg_info = (tNFA_DM_API_REG_NDEF_HDLR*)p_data;
  tNFA_NDEF_REGISTER ndef_register;

  /* If registering default handler, check to see if one is already registered
   */
  if (p_reg_info->tnf == NFA_TNF_DEFAULT) {
    /* check if default handler is already registered */
    if (p_cb->p_ndef_handler[NFA_NDEF_DEFAULT_HANDLER_IDX]) {
      LOG(WARNING) << StringPrintf("Default NDEF handler being changed.");

      /* Free old registration info */
      nfa_dm_ndef_dereg_hdlr_by_handle(
          (tNFA_HANDLE)NFA_NDEF_DEFAULT_HANDLER_IDX);
    }
    DLOG_IF(INFO, nfc_debug_enabled)
        << StringPrintf("Default NDEF handler successfully registered.");
    hdlr_idx = NFA_NDEF_DEFAULT_HANDLER_IDX;
  }
  /* Get available entry in ndef_handler table, and check if requested type is
     already registered */
  else {
    hdlr_idx = NFA_HANDLE_INVALID;

    /* Check if this type is already registered */
    for (i = (NFA_NDEF_DEFAULT_HANDLER_IDX + 1); i < NFA_NDEF_MAX_HANDLERS;
         i++) {
      /* If this is a free slot, then remember it */
      if (p_cb->p_ndef_handler[i] == nullptr) {
        hdlr_idx = i;
        break;
      }
    }
  }

  if (hdlr_idx != NFA_HANDLE_INVALID) {
    /* Update the table */
    p_cb->p_ndef_handler[hdlr_idx] = p_reg_info;

    p_reg_info->ndef_type_handle =
        (tNFA_HANDLE)(NFA_HANDLE_GROUP_NDEF_HANDLER | hdlr_idx);

    ndef_register.ndef_type_handle = p_reg_info->ndef_type_handle;
    ndef_register.status = NFA_STATUS_OK;

    DLOG_IF(INFO, nfc_debug_enabled)
        << StringPrintf("NDEF handler successfully registered. Handle=0x%08x",
                        p_reg_info->ndef_type_handle);
    tNFA_NDEF_EVT_DATA nfa_ndef_evt_data;
    nfa_ndef_evt_data.ndef_reg = ndef_register;
    (*(p_reg_info->p_ndef_cback))(NFA_NDEF_REGISTER_EVT, &nfa_ndef_evt_data);

    /* indicate that we will free message buffer when type_handler is
     * deregistered */
    return false;
  } else {
    /* Error */
    LOG(ERROR) << StringPrintf("NDEF handler failed to register.");
    ndef_register.ndef_type_handle = NFA_HANDLE_INVALID;
    ndef_register.status = NFA_STATUS_FAILED;
    tNFA_NDEF_EVT_DATA nfa_ndef_evt_data;
    nfa_ndef_evt_data.ndef_reg = ndef_register;
    (*(p_reg_info->p_ndef_cback))(NFA_NDEF_REGISTER_EVT, &nfa_ndef_evt_data);

    return true;
  }
}

/*******************************************************************************
**
** Function         nfa_dm_ndef_dereg_hdlr
**
** Description      Deregister NDEF record type handler
**
** Returns          TRUE (message buffer to be freed by caller)
**
*******************************************************************************/
bool nfa_dm_ndef_dereg_hdlr(tNFA_DM_MSG* p_data) {
  tNFA_DM_API_DEREG_NDEF_HDLR* p_dereginfo =
      (tNFA_DM_API_DEREG_NDEF_HDLR*)p_data;

  /* Make sure this is a NDEF_HDLR handle */
  if (((p_dereginfo->ndef_type_handle & NFA_HANDLE_GROUP_MASK) !=
       NFA_HANDLE_GROUP_NDEF_HANDLER) ||
      ((p_dereginfo->ndef_type_handle & NFA_HANDLE_MASK) >=
       NFA_NDEF_MAX_HANDLERS)) {
    LOG(ERROR) << StringPrintf("Invalid handle for NDEF type handler: 0x%08x",
                               p_dereginfo->ndef_type_handle);
  } else {
    nfa_dm_ndef_dereg_hdlr_by_handle(p_dereginfo->ndef_type_handle);
  }

  return true;
}

/*******************************************************************************
**
** Function         nfa_dm_ndef_find_next_handler
**
** Description      Find next ndef handler for a given record type
**
** Returns          void
**
*******************************************************************************/
tNFA_DM_API_REG_NDEF_HDLR* nfa_dm_ndef_find_next_handler(
    tNFA_DM_API_REG_NDEF_HDLR* p_init_handler, uint8_t tnf,
    uint8_t* p_type_name, uint8_t type_name_len, uint8_t* p_payload,
    uint32_t payload_len) {
  tNFA_DM_CB* p_cb = &nfa_dm_cb;
  uint8_t i;

  /* if init_handler is NULL, then start with the first non-default handler */
  if (!p_init_handler)
    i = NFA_NDEF_DEFAULT_HANDLER_IDX + 1;
  else {
    /* Point to handler index after p_init_handler */
    i = (p_init_handler->ndef_type_handle & NFA_HANDLE_MASK) + 1;
  }

  /* Look for next handler */
  for (; i < NFA_NDEF_MAX_HANDLERS; i++) {
    /* Check if TNF matches */
    if ((p_cb->p_ndef_handler[i]) && (p_cb->p_ndef_handler[i]->tnf == tnf)) {
      /* TNF matches. */
      /* If handler is for a specific URI type, check if type is WKT URI, */
      /* and that the URI prefix abrieviation for this handler matches */
      if (p_cb->p_ndef_handler[i]->flags & NFA_NDEF_FLAGS_WKT_URI) {
        /* This is a handler for a specific URI type */
        /* Check if this recurd is WKT URI */
        if ((p_payload) && (type_name_len == 1) && (*p_type_name == 'U')) {
          /* Check if URI prefix abrieviation matches */
          if ((payload_len > 1) &&
              (p_payload[0] == p_cb->p_ndef_handler[i]->uri_id)) {
            /* URI prefix abrieviation matches */
            /* If handler does not specify an absolute URI, then match found. */
            /* If absolute URI, then compare URI for match (skip over uri_id in
             * ndef payload) */
            if ((p_cb->p_ndef_handler[i]->uri_id != NFA_NDEF_URI_ID_ABSOLUTE) ||
                ((payload_len > p_cb->p_ndef_handler[i]->name_len) &&
                 (memcmp(&p_payload[1], p_cb->p_ndef_handler[i]->name,
                         p_cb->p_ndef_handler[i]->name_len) == 0))) {
              /* Handler found. */
              break;
            }
          }
          /* Check if handler is absolute URI but NDEF is using prefix
             abrieviation */
          else if ((p_cb->p_ndef_handler[i]->uri_id ==
                    NFA_NDEF_URI_ID_ABSOLUTE) &&
                   (p_payload[0] != NFA_NDEF_URI_ID_ABSOLUTE)) {
            /* Handler is absolute URI but NDEF is using prefix abrieviation.
             * Compare URI prefix */
            if ((p_payload[0] < NFA_DM_NDEF_WKT_URI_STR_TBL_SIZE) &&
                strlen(
                    (const char*)nfa_dm_ndef_wkt_uri_str_tbl[p_payload[0]]) >=
                    p_cb->p_ndef_handler[i]->name_len &&
                (memcmp(p_cb->p_ndef_handler[i]->name,
                        (char*)nfa_dm_ndef_wkt_uri_str_tbl[p_payload[0]],
                        p_cb->p_ndef_handler[i]->name_len) == 0)) {
              /* Handler found. */
              break;
            }
          }
          /* Check if handler is using prefix abrieviation, but NDEF is using
             absolute URI */
          else if ((p_cb->p_ndef_handler[i]->uri_id !=
                    NFA_NDEF_URI_ID_ABSOLUTE) &&
                   (p_payload[0] == NFA_NDEF_URI_ID_ABSOLUTE)) {
            /* Handler is using prefix abrieviation, but NDEF is using absolute
             * URI. Compare URI prefix */
            if ((p_cb->p_ndef_handler[i]->uri_id <
                 NFA_DM_NDEF_WKT_URI_STR_TBL_SIZE) &&
                payload_len > strlen((const char*)nfa_dm_ndef_wkt_uri_str_tbl
                                         [p_cb->p_ndef_handler[i]->uri_id]) &&
                (memcmp(&p_payload[1],
                        nfa_dm_ndef_wkt_uri_str_tbl[p_cb->p_ndef_handler[i]
                                                        ->uri_id],
                        strlen((const char*)nfa_dm_ndef_wkt_uri_str_tbl
                                   [p_cb->p_ndef_handler[i]->uri_id])) == 0)) {
              /* Handler found. */
              break;
            }
          }
        }
      }
      /* Not looking for specific URI. Check if type_name for this handler
         matches the NDEF record's type_name */
      else if (p_cb->p_ndef_handler[i]->name_len == type_name_len) {
        if ((type_name_len == 0) || (memcmp(p_cb->p_ndef_handler[i]->name,
                                            p_type_name, type_name_len) == 0)) {
          /* Handler found */
          break;
        }
      }
    }
  }

  if (i < NFA_NDEF_MAX_HANDLERS)
    return (p_cb->p_ndef_handler[i]);
  else
    return (nullptr);
}

/*******************************************************************************
**
** Function         nfa_dm_ndef_clear_notified_flag
**
** Description      Clear 'whole_message_notified' flag for all the handlers
**                  (flag used to indicate that this handler has already
**                  handled the entire incoming NDEF message)
**
** Returns          void
**
*******************************************************************************/
void nfa_dm_ndef_clear_notified_flag(void) {
  tNFA_DM_CB* p_cb = &nfa_dm_cb;
  uint8_t i;

  for (i = 0; i < NFA_NDEF_MAX_HANDLERS; i++) {
    if (p_cb->p_ndef_handler[i]) {
      p_cb->p_ndef_handler[i]->flags &= ~NFA_NDEF_FLAGS_WHOLE_MESSAGE_NOTIFIED;
    }
  }
}

/*******************************************************************************
**
** Function         nfa_dm_ndef_handle_message
**
** Description      Handle incoming ndef message
**
** Returns          void
**
*******************************************************************************/
void nfa_dm_ndef_handle_message(tNFA_STATUS status, uint8_t* p_msg_buf,
                                uint32_t len) {
  tNFA_DM_CB* p_cb = &nfa_dm_cb;
  tNDEF_STATUS ndef_status;
  uint8_t *p_rec, *p_ndef_start, *p_type, *p_payload, *p_rec_end;
  uint32_t payload_len;
  uint8_t tnf, type_len, rec_hdr_flags, id_len;
  tNFA_DM_API_REG_NDEF_HDLR* p_handler;
  tNFA_NDEF_DATA ndef_data;
  uint8_t rec_count = 0;
  bool record_handled, entire_message_handled;

  DLOG_IF(INFO, nfc_debug_enabled) << StringPrintf(
      "nfa_dm_ndef_handle_message status=%i, len=%i", status, len);

  if (status != NFA_STATUS_OK) {
    /* If problem reading NDEF message, then exit (no action required) */
    return;
  }

  /* If in exclusive RF mode is activer, then route NDEF message callback
   * registered with NFA_StartExclusiveRfControl */
  if ((p_cb->flags & NFA_DM_FLAGS_EXCL_RF_ACTIVE) &&
      (p_cb->p_excl_ndef_cback)) {
    /* No ndef-handler handle, since this callback is not from
     * RegisterNDefHandler */
    ndef_data.ndef_type_handle = 0;
    ndef_data.p_data = p_msg_buf;
    ndef_data.len = len;
    tNFA_NDEF_EVT_DATA nfa_ndef_evt_data;
    nfa_ndef_evt_data.ndef_data = ndef_data;
    (*p_cb->p_excl_ndef_cback)(NFA_NDEF_DATA_EVT, &nfa_ndef_evt_data);
    return;
  }

  /* Handle zero length - notify default handler */
  if (len == 0) {
    p_handler = p_cb->p_ndef_handler[NFA_NDEF_DEFAULT_HANDLER_IDX];
    if (p_handler != nullptr) {
      DLOG_IF(INFO, nfc_debug_enabled) << StringPrintf(
          "Notifying default handler of zero-length NDEF message...");
      ndef_data.ndef_type_handle = p_handler->ndef_type_handle;
      ndef_data.p_data = nullptr; /* Start of record */
      ndef_data.len = 0;
      tNFA_NDEF_EVT_DATA nfa_ndef_evt_data;
      nfa_ndef_evt_data.ndef_data = ndef_data;
      (*p_handler->p_ndef_cback)(NFA_NDEF_DATA_EVT, &nfa_ndef_evt_data);
    }
    return;
  }

  /* Validate the NDEF message */
  ndef_status = NDEF_MsgValidate(p_msg_buf, len, true);
  if (ndef_status != NDEF_OK) {
    LOG(ERROR) << StringPrintf(
        "Received invalid NDEF message. NDEF status=0x%x", ndef_status);
    return;
  }

  /* NDEF message received from backgound polling. Pass the NDEF message to the
   * NDEF handlers */

  /* New NDEF message. Clear 'notified' flag for all the handlers */
  nfa_dm_ndef_clear_notified_flag();

  /* Indicate that no handler has handled this entire NDEF message (e.g.
   * connection-handover handler *) */
  entire_message_handled = false;

  /* Get first record in message */
  p_rec = p_ndef_start = p_msg_buf;

  /* Check each record in the NDEF message */
  while (p_rec != nullptr) {
    /* Get record type */
    p_type = NDEF_RecGetType(p_rec, &tnf, &type_len);

    /* Indicate record not handled yet */
    record_handled = false;

    /* Get pointer to record payload */
    p_payload = NDEF_RecGetPayload(p_rec, &payload_len);

    /* Find first handler for this type */
    p_handler = nfa_dm_ndef_find_next_handler(nullptr, tnf, p_type, type_len,
                                              p_payload, payload_len);
    if (p_handler == nullptr) {
      /* Not a registered NDEF type. Use default handler */
      p_handler = p_cb->p_ndef_handler[NFA_NDEF_DEFAULT_HANDLER_IDX];
      if (p_handler != nullptr) {
        DLOG_IF(INFO, nfc_debug_enabled)
            << StringPrintf("No handler found. Using default handler...");
      }
    }

    while (p_handler) {
      /* If handler is for whole NDEF message, and it has already been notified,
       * then skip notification */
      if (p_handler->flags & NFA_NDEF_FLAGS_WHOLE_MESSAGE_NOTIFIED) {
        /* Look for next handler */
        p_handler = nfa_dm_ndef_find_next_handler(
            p_handler, tnf, p_type, type_len, p_payload, payload_len);
        continue;
      }

      /* Get pointer to record payload */
      DLOG_IF(INFO, nfc_debug_enabled) << StringPrintf(
          "Calling ndef type handler (%x)", p_handler->ndef_type_handle);

      ndef_data.ndef_type_handle = p_handler->ndef_type_handle;
      ndef_data.p_data = p_rec; /* Start of record */

      /* Calculate length of NDEF record */
      if (p_payload != nullptr)
        ndef_data.len = payload_len + (uint32_t)(p_payload - p_rec);
      else {
        /* If no payload, calculate length of ndef record header */
        p_rec_end = p_rec;

        /* First byte is the header flags */
        rec_hdr_flags = *p_rec_end++;

        /* Next byte is the type field length */
        type_len = *p_rec_end++;

        /* Next is the payload length (1 or 4 bytes) */
        if (rec_hdr_flags & NDEF_SR_MASK) {
          p_rec_end++;
        } else {
          p_rec_end += 4;
        }

        /* ID field Length */
        if (rec_hdr_flags & NDEF_IL_MASK)
          id_len = *p_rec_end++;
        else
          id_len = 0;
        p_rec_end += id_len;

        ndef_data.len = (uint32_t)(p_rec_end - p_rec);
      }

      /* If handler wants entire ndef message, then pass pointer to start of
       * message and  */
      /* set 'notified' flag so handler won't get notified on subsequent records
       * for this */
      /* NDEF message. */
      if (p_handler->flags & NFA_NDEF_FLAGS_HANDLE_WHOLE_MESSAGE) {
        ndef_data.p_data = p_ndef_start; /* Start of NDEF message */
        ndef_data.len = len;
        p_handler->flags |= NFA_NDEF_FLAGS_WHOLE_MESSAGE_NOTIFIED;

        /* Indicate that at least one handler has received entire NDEF message
         */
        entire_message_handled = true;
      }

      /* Notify NDEF type handler */
      tNFA_NDEF_EVT_DATA nfa_ndef_evt_data;
      nfa_ndef_evt_data.ndef_data = ndef_data;
      (*p_handler->p_ndef_cback)(NFA_NDEF_DATA_EVT, &nfa_ndef_evt_data);

      /* Indicate that at lease one handler has received this record */
      record_handled = true;

      /* Look for next handler */
      p_handler = nfa_dm_ndef_find_next_handler(
          p_handler, tnf, p_type, type_len, p_payload, payload_len);
    }

    /* Check if at least one handler was notified of this record (only happens
     * if no default handler was register) */
    if ((!record_handled) && (!entire_message_handled)) {
      /* Unregistered NDEF record type; no default handler */
      LOG(WARNING) << StringPrintf("Unhandled NDEF record (#%i)", rec_count);
    }

    rec_count++;
    p_rec = NDEF_MsgGetNextRec(p_rec);
  }
}