halimpl/bcm2079x/adaptation/StartupConfig.cpp

/******************************************************************************
 *
 *  Copyright (C) 1999-2012 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.
 *
 ******************************************************************************/

/******************************************************************************
 * Construct a buffer that contains multiple Type-Length-Value contents
 * that is used by the HAL in a CORE_SET_CONFIG NCI command.
 ******************************************************************************/

#define LOG_TAG "NfcNciHal"
#include "StartupConfig.h"
#include "_OverrideLog.h"

const uint8_t StartupConfig::mMaxLength = 255;

/*******************************************************************************
**
** Function:        initialize
**
** Description:     Initialize all member variables.
**
** Returns:         None
**
*******************************************************************************/
StartupConfig::StartupConfig() {
  // set first byte to 0, which is length of payload
  mBuffer.append((uint8_string::size_type)1, (uint8_string::value_type)0);
}

/*******************************************************************************
**
** Function:        initialize
**
** Description:     Reset all member variables.
**
** Returns:         None
**
*******************************************************************************/
void StartupConfig::initialize() {
  mBuffer.clear();
  // set first byte to 0, which is length of payload
  mBuffer.append((uint8_string::size_type)1, (uint8_string::value_type)0);
}

/*******************************************************************************
**
** Function:        getInternalBuffer
**
** Description:     Get the pointer to buffer that contains multiple
**                  Type-Length-Value contents.
**
** Returns:         Pointer to buffer.
**
*******************************************************************************/
const uint8_t* StartupConfig::getInternalBuffer() { return mBuffer.data(); }

/*******************************************************************************
**
** Function:        append
**
** Description:     Append new config data to internal buffer.
**                  newContent: buffer containing new content; newContent[0] is
**                          payload length; newContent[1..end] is payload.
**                  newContentLen: total length of newContent.
**
** Returns:         True if ok.
**
*******************************************************************************/
bool StartupConfig::append(const uint8_t* newContent, uint8_t newContentLen) {
  static const char fn[] = "StartupConfig::append";
  if ((newContentLen + mBuffer.size()) > mMaxLength) {
    ALOGE("%s: exceed max length", fn);
    return false;
  }

  ALOGD("%s: try append %zu bytes", fn,
        (uint8_string::size_type)(newContentLen));
  // append new payload into private buffer
  mBuffer.append(newContent + 1, (uint8_string::size_type)(newContentLen - 1));
  // increase size counter of payload in private buffer
  mBuffer[0] = mBuffer[0] + newContentLen - 1;
  ALOGD("%s: new size %u bytes", fn, mBuffer[0]);
  return true;
};

/*******************************************************************************
**
** Function:        disableSecureElement
**
** Description:     Adjust a TLV to disable secure element(s).  The TLV's type
*is 0xC2.
**                  bitmask: 0xC0 = do not detect any secure element.
**                           0x40 = do not detect secure element in slot 0.
**                           0x80 = do not detect secure element in slot 1.
**
** Returns:         True if ok.
**
*******************************************************************************/
bool StartupConfig::disableSecureElement(uint8_t bitmask) {
  const uint8_t maxLen = mBuffer[0];
  uint8_t index = 1, tlvType = 0, tlvLen = 0;
  bool found0xC2 = false;

  while (true) {
    if (index > maxLen) break;
    tlvType = mBuffer[index];
    index++;
    tlvLen = mBuffer[index];
    index++;
    if (tlvType == 0xC2)  // this TLV controls secure elements
    {
      index++;  // index of second byte in TLV's value
      mBuffer[index] = mBuffer[index] | bitmask;  // turn on certain bits
      found0xC2 = true;
    } else
      index += tlvLen;
  }

  if (found0xC2 == false) {
    uint8_t tlv[] = {0x04, 0xC2, 0x02, 0x61, 0x00};
    tlv[4] = tlv[4] | bitmask;
    found0xC2 = append(tlv, 5);
  }
  return found0xC2;
}