av/rtmp/rtmp_c/librtmp/amf.c

/*
 *      Copyright (C) 2005-2008 Team XBMC
 *      http://www.xbmc.org
 *      Copyright (C) 2008-2009 Andrej Stepanchuk
 *      Copyright (C) 2009-2010 Howard Chu
 *
 *  This file is part of librtmp.
 *
 *  librtmp is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as
 *  published by the Free Software Foundation; either version 2.1,
 *  or (at your option) any later version.
 *
 *  librtmp is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with librtmp see the file COPYING.  If not, write to
 *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 *  Boston, MA  02110-1301, USA.
 *  http://www.gnu.org/copyleft/lgpl.html
 */

#include <string.h>
#include <assert.h>
#include <stdlib.h>

#include "rtmp_sys.h"
#include "amf.h"
#include "log.h"
#include "bytes.h"

static const AMFObjectProperty AMFProp_Invalid = { {0, 0}, AMF_INVALID };
static const AMFObject AMFObj_Invalid = { 0, 0 };
static const AVal AV_empty = { 0, 0 };

/* Data is Big-Endian */
unsigned short
AMF_DecodeInt16(const char *data)
{
  unsigned char *c = (unsigned char *) data;
  unsigned short val;
  val = (c[0] << 8) | c[1];
  return val;
}

unsigned int
AMF_DecodeInt24(const char *data)
{
  unsigned char *c = (unsigned char *) data;
  unsigned int val;
  val = (c[0] << 16) | (c[1] << 8) | c[2];
  return val;
}

unsigned int
AMF_DecodeInt32(const char *data)
{
  unsigned char *c = (unsigned char *)data;
  unsigned int val;
  val = (c[0] << 24) | (c[1] << 16) | (c[2] << 8) | c[3];
  return val;
}

void
AMF_DecodeString(const char *data, AVal *bv)
{
  bv->av_len = AMF_DecodeInt16(data);
  bv->av_val = (bv->av_len > 0) ? (char *)data + 2 : NULL;
}

void
AMF_DecodeLongString(const char *data, AVal *bv)
{
  bv->av_len = AMF_DecodeInt32(data);
  bv->av_val = (bv->av_len > 0) ? (char *)data + 4 : NULL;
}

double
AMF_DecodeNumber(const char *data)
{
  double dVal;
#if __FLOAT_WORD_ORDER == __BYTE_ORDER
#if __BYTE_ORDER == __BIG_ENDIAN
  memcpy(&dVal, data, 8);
#elif __BYTE_ORDER == __LITTLE_ENDIAN
  unsigned char *ci, *co;
  ci = (unsigned char *)data;
  co = (unsigned char *)&dVal;
  co[0] = ci[7];
  co[1] = ci[6];
  co[2] = ci[5];
  co[3] = ci[4];
  co[4] = ci[3];
  co[5] = ci[2];
  co[6] = ci[1];
  co[7] = ci[0];
#endif
#else
#if __BYTE_ORDER == __LITTLE_ENDIAN	/* __FLOAT_WORD_ORER == __BIG_ENDIAN */
  unsigned char *ci, *co;
  ci = (unsigned char *)data;
  co = (unsigned char *)&dVal;
  co[0] = ci[3];
  co[1] = ci[2];
  co[2] = ci[1];
  co[3] = ci[0];
  co[4] = ci[7];
  co[5] = ci[6];
  co[6] = ci[5];
  co[7] = ci[4];
#else /* __BYTE_ORDER == __BIG_ENDIAN && __FLOAT_WORD_ORER == __LITTLE_ENDIAN */
  unsigned char *ci, *co;
  ci = (unsigned char *)data;
  co = (unsigned char *)&dVal;
  co[0] = ci[4];
  co[1] = ci[5];
  co[2] = ci[6];
  co[3] = ci[7];
  co[4] = ci[0];
  co[5] = ci[1];
  co[6] = ci[2];
  co[7] = ci[3];
#endif
#endif
  return dVal;
}

int
AMF_DecodeBoolean(const char *data)
{
  return *data != 0;
}

char *
AMF_EncodeInt16(char *output, char *outend, short nVal)
{
  if (output+2 > outend)
    return NULL;

  output[1] = nVal & 0xff;
  output[0] = nVal >> 8;
  return output+2;
}

char *
AMF_EncodeInt24(char *output, char *outend, int nVal)
{
  if (output+3 > outend)
    return NULL;

  output[2] = nVal & 0xff;
  output[1] = nVal >> 8;
  output[0] = nVal >> 16;
  return output+3;
}

char *
AMF_EncodeInt32(char *output, char *outend, int nVal)
{
  if (output+4 > outend)
    return NULL;

  output[3] = nVal & 0xff;
  output[2] = nVal >> 8;
  output[1] = nVal >> 16;
  output[0] = nVal >> 24;
  return output+4;
}

char *
AMF_EncodeString(char *output, char *outend, const AVal *bv)
{
  if ((bv->av_len < 65536 && output + 1 + 2 + bv->av_len > outend) ||
	output + 1 + 4 + bv->av_len > outend)
    return NULL;

  if (bv->av_len < 65536)
    {
      *output++ = AMF_STRING;

      output = AMF_EncodeInt16(output, outend, bv->av_len);
    }
  else
    {
      *output++ = AMF_LONG_STRING;

      output = AMF_EncodeInt32(output, outend, bv->av_len);
    }
  memcpy(output, bv->av_val, bv->av_len);
  output += bv->av_len;

  return output;
}

char *
AMF_EncodeNumber(char *output, char *outend, double dVal)
{
  if (output+1+8 > outend)
    return NULL;

  *output++ = AMF_NUMBER;	/* type: Number */

#if __FLOAT_WORD_ORDER == __BYTE_ORDER
#if __BYTE_ORDER == __BIG_ENDIAN
  memcpy(output, &dVal, 8);
#elif __BYTE_ORDER == __LITTLE_ENDIAN
  {
    unsigned char *ci, *co;
    ci = (unsigned char *)&dVal;
    co = (unsigned char *)output;
    co[0] = ci[7];
    co[1] = ci[6];
    co[2] = ci[5];
    co[3] = ci[4];
    co[4] = ci[3];
    co[5] = ci[2];
    co[6] = ci[1];
    co[7] = ci[0];
  }
#endif
#else
#if __BYTE_ORDER == __LITTLE_ENDIAN	/* __FLOAT_WORD_ORER == __BIG_ENDIAN */
  {
    unsigned char *ci, *co;
    ci = (unsigned char *)&dVal;
    co = (unsigned char *)output;
    co[0] = ci[3];
    co[1] = ci[2];
    co[2] = ci[1];
    co[3] = ci[0];
    co[4] = ci[7];
    co[5] = ci[6];
    co[6] = ci[5];
    co[7] = ci[4];
  }
#else /* __BYTE_ORDER == __BIG_ENDIAN && __FLOAT_WORD_ORER == __LITTLE_ENDIAN */
  {
    unsigned char *ci, *co;
    ci = (unsigned char *)&dVal;
    co = (unsigned char *)output;
    co[0] = ci[4];
    co[1] = ci[5];
    co[2] = ci[6];
    co[3] = ci[7];
    co[4] = ci[0];
    co[5] = ci[1];
    co[6] = ci[2];
    co[7] = ci[3];
  }
#endif
#endif

  return output+8;
}

char *
AMF_EncodeBoolean(char *output, char *outend, int bVal)
{
  if (output+2 > outend)
    return NULL;

  *output++ = AMF_BOOLEAN;

  *output++ = bVal ? 0x01 : 0x00;

  return output;
}

char *
AMF_EncodeNamedString(char *output, char *outend, const AVal *strName, const AVal *strValue)
{
  if (output+2+strName->av_len > outend)
    return NULL;
  output = AMF_EncodeInt16(output, outend, strName->av_len);

  memcpy(output, strName->av_val, strName->av_len);
  output += strName->av_len;

  return AMF_EncodeString(output, outend, strValue);
}

char *
AMF_EncodeNamedNumber(char *output, char *outend, const AVal *strName, double dVal)
{
  if (output+2+strName->av_len > outend)
    return NULL;
  output = AMF_EncodeInt16(output, outend, strName->av_len);

  memcpy(output, strName->av_val, strName->av_len);
  output += strName->av_len;

  return AMF_EncodeNumber(output, outend, dVal);
}

char *
AMF_EncodeNamedBoolean(char *output, char *outend, const AVal *strName, int bVal)
{
  if (output+2+strName->av_len > outend)
    return NULL;
  output = AMF_EncodeInt16(output, outend, strName->av_len);

  memcpy(output, strName->av_val, strName->av_len);
  output += strName->av_len;

  return AMF_EncodeBoolean(output, outend, bVal);
}

void
AMFProp_GetName(AMFObjectProperty *prop, AVal *name)
{
  *name = prop->p_name;
}

void
AMFProp_SetName(AMFObjectProperty *prop, AVal *name)
{
  prop->p_name = *name;
}

AMFDataType
AMFProp_GetType(AMFObjectProperty *prop)
{
  return prop->p_type;
}

double
AMFProp_GetNumber(AMFObjectProperty *prop)
{
  return prop->p_vu.p_number;
}

int
AMFProp_GetBoolean(AMFObjectProperty *prop)
{
  return prop->p_vu.p_number != 0;
}

void
AMFProp_GetString(AMFObjectProperty *prop, AVal *str)
{
  if (prop->p_type == AMF_STRING)
    *str = prop->p_vu.p_aval;
  else
    *str = AV_empty;
}

void
AMFProp_GetObject(AMFObjectProperty *prop, AMFObject *obj)
{
  if (prop->p_type == AMF_OBJECT)
    *obj = prop->p_vu.p_object;
  else
    *obj = AMFObj_Invalid;
}

int
AMFProp_IsValid(AMFObjectProperty *prop)
{
  return prop->p_type != AMF_INVALID;
}

char *
AMFProp_Encode(AMFObjectProperty *prop, char *pBuffer, char *pBufEnd)
{
  if (prop->p_type == AMF_INVALID)
    return NULL;

  if (prop->p_type != AMF_NULL && pBuffer + prop->p_name.av_len + 2 + 1 >= pBufEnd)
    return NULL;

  if (prop->p_type != AMF_NULL && prop->p_name.av_len)
    {
      *pBuffer++ = prop->p_name.av_len >> 8;
      *pBuffer++ = prop->p_name.av_len & 0xff;
      memcpy(pBuffer, prop->p_name.av_val, prop->p_name.av_len);
      pBuffer += prop->p_name.av_len;
    }

  switch (prop->p_type)
    {
    case AMF_NUMBER:
      pBuffer = AMF_EncodeNumber(pBuffer, pBufEnd, prop->p_vu.p_number);
      break;

    case AMF_BOOLEAN:
      pBuffer = AMF_EncodeBoolean(pBuffer, pBufEnd, prop->p_vu.p_number != 0);
      break;

    case AMF_STRING:
      pBuffer = AMF_EncodeString(pBuffer, pBufEnd, &prop->p_vu.p_aval);
      break;

    case AMF_NULL:
      if (pBuffer+1 >= pBufEnd)
        return NULL;
      *pBuffer++ = AMF_NULL;
      break;

    case AMF_OBJECT:
      pBuffer = AMF_Encode(&prop->p_vu.p_object, pBuffer, pBufEnd);
      break;

    case AMF_ECMA_ARRAY:
      pBuffer = AMF_EncodeEcmaArray(&prop->p_vu.p_object, pBuffer, pBufEnd);
      break;

    case AMF_STRICT_ARRAY:
      pBuffer = AMF_EncodeArray(&prop->p_vu.p_object, pBuffer, pBufEnd);
      break;

    default:
      RTMP_Log(RTMP_LOGERROR, "%s, invalid type. %d", __FUNCTION__, prop->p_type);
      pBuffer = NULL;
    };

  return pBuffer;
}

#define AMF3_INTEGER_MAX	268435455
#define AMF3_INTEGER_MIN	-268435456

int
AMF3ReadInteger(const char *data, int32_t *valp)
{
  int i = 0;
  int32_t val = 0;

  while (i <= 2)
    {				/* handle first 3 bytes */
      if (data[i] & 0x80)
	{			/* byte used */
	  val <<= 7;		/* shift up */
	  val |= (data[i] & 0x7f);	/* add bits */
	  i++;
	}
      else
	{
	  break;
	}
    }

  if (i > 2)
    {				/* use 4th byte, all 8bits */
      val <<= 8;
      val |= data[3];

      /* range check */
      if (val > AMF3_INTEGER_MAX)
	val -= (1 << 29);
    }
  else
    {				/* use 7bits of last unparsed byte (0xxxxxxx) */
      val <<= 7;
      val |= data[i];
    }

  *valp = val;

  return i > 2 ? 4 : i + 1;
}

int
AMF3ReadString(const char *data, AVal *str)
{
  int32_t ref = 0;
  int len;
  assert(str != 0);

  len = AMF3ReadInteger(data, &ref);
  data += len;

  if ((ref & 0x1) == 0)
    {				/* reference: 0xxx */
      uint32_t refIndex = (ref >> 1);
      RTMP_Log(RTMP_LOGDEBUG,
	  "%s, string reference, index: %d, not supported, ignoring!",
	  __FUNCTION__, refIndex);
	  str->av_val = NULL;
	  str->av_len = 0;
      return len;
    }
  else
    {
      uint32_t nSize = (ref >> 1);

      str->av_val = (char *)data;
      str->av_len = nSize;

      return len + nSize;
    }
  return len;
}

int
AMF3Prop_Decode(AMFObjectProperty *prop, const char *pBuffer, int nSize,
		int bDecodeName)
{
  int nOriginalSize = nSize;
  AMF3DataType type;

  prop->p_name.av_len = 0;
  prop->p_name.av_val = NULL;

  if (nSize == 0 || !pBuffer)
    {
      RTMP_Log(RTMP_LOGDEBUG, "empty buffer/no buffer pointer!");
      return -1;
    }

  /* decode name */
  if (bDecodeName)
    {
      AVal name;
      int nRes = AMF3ReadString(pBuffer, &name);

      if (name.av_len <= 0)
	return nRes;

      nSize -= nRes;
      if (nSize <= 0)
	return -1;
      prop->p_name = name;
      pBuffer += nRes;
    }

  /* decode */
  type = *pBuffer++;
  nSize--;

  switch (type)
    {
    case AMF3_UNDEFINED: