Ejemplo n.º 1
0
  static FT_Error
  check_type1_format( FT_Stream    stream,
                      const char*  header_string,
                      size_t       header_length )
  {
    FT_Error   error;
    FT_UShort  tag;
    FT_Long    size;


    if ( FT_STREAM_SEEK( 0 ) )
      goto Exit;

    error = read_pfb_tag( stream, &tag, &size );
    if ( error )
      goto Exit;

    if ( tag != 0x8001U && FT_STREAM_SEEK( 0 ) )
      goto Exit;

    if ( !FT_FRAME_ENTER( header_length ) )
    {
      error = 0;

      if ( ft_memcmp( stream->cursor, header_string, header_length ) != 0 )
        error = T1_Err_Unknown_File_Format;

      FT_FRAME_EXIT();
    }

  Exit:
    return error;
  }
  static FT_Error
  check_type1_format( FT_Stream    stream,
                      const char*  header_string,
                      size_t       header_length )
  {
    FT_Error   error;
    FT_UShort  tag;
    FT_ULong   dummy;


    if ( FT_STREAM_SEEK( 0 ) )
      goto Exit;

    error = read_pfb_tag( stream, &tag, &dummy );
    if ( error )
      goto Exit;

    /* We assume that the first segment in a PFB is always encoded as   */
    /* text.  This might be wrong (and the specification doesn't insist */
    /* on that), but we have never seen a counterexample.               */
    if ( tag != 0x8001U && FT_STREAM_SEEK( 0 ) )
      goto Exit;

    if ( !FT_FRAME_ENTER( header_length ) )
    {
      error = FT_Err_Ok;

      if ( ft_memcmp( stream->cursor, header_string, header_length ) != 0 )
        error = FT_THROW( Unknown_File_Format );

      FT_FRAME_EXIT();
    }

  Exit:
    return error;
  }
  T1_Get_Private_Dict( T1_Parser      parser,
                       PSAux_Service  psaux )
  {
    FT_Stream  stream = parser->stream;
    FT_Memory  memory = parser->root.memory;
    FT_Error   error  = FT_Err_Ok;
    FT_ULong   size;


    if ( parser->in_pfb )
    {
      /* in the case of the PFB format, the private dictionary can be  */
      /* made of several segments.  We thus first read the number of   */
      /* segments to compute the total size of the private dictionary  */
      /* then re-read them into memory.                                */
      FT_Long    start_pos = FT_STREAM_POS();
      FT_UShort  tag;


      parser->private_len = 0;
      for (;;)
      {
        error = read_pfb_tag( stream, &tag, &size );
        if ( error )
          goto Fail;

        if ( tag != 0x8002U )
          break;

        parser->private_len += size;

        if ( FT_STREAM_SKIP( size ) )
          goto Fail;
      }

      /* Check that we have a private dictionary there */
      /* and allocate private dictionary buffer        */
      if ( parser->private_len == 0 )
      {
        FT_ERROR(( "T1_Get_Private_Dict:"
                   " invalid private dictionary section\n" ));
        error = FT_THROW( Invalid_File_Format );
        goto Fail;
      }

      if ( FT_STREAM_SEEK( start_pos )                           ||
           FT_ALLOC( parser->private_dict, parser->private_len ) )
        goto Fail;

      parser->private_len = 0;
      for (;;)
      {
        error = read_pfb_tag( stream, &tag, &size );
        if ( error || tag != 0x8002U )
        {
          error = FT_Err_Ok;
          break;
        }

        if ( FT_STREAM_READ( parser->private_dict + parser->private_len,
                             size ) )
          goto Fail;

        parser->private_len += size;
      }
    }
    else
    {
      /* We have already `loaded' the whole PFA font file into memory; */
      /* if this is a memory resource, allocate a new block to hold    */
      /* the private dict.  Otherwise, simply overwrite into the base  */
      /* dictionary block in the heap.                                 */

      /* first of all, look at the `eexec' keyword */
      FT_Byte*  cur   = parser->base_dict;
      FT_Byte*  limit = cur + parser->base_len;
      FT_Byte   c;


    Again:
      for (;;)
      {
        c = cur[0];
        if ( c == 'e' && cur + 9 < limit )  /* 9 = 5 letters for `eexec' + */
                                            /* whitespace + 4 chars        */
        {
          if ( cur[1] == 'e' &&
               cur[2] == 'x' &&
               cur[3] == 'e' &&
               cur[4] == 'c' )
            break;
        }
        cur++;
        if ( cur >= limit )
        {
          FT_ERROR(( "T1_Get_Private_Dict:"
                     " could not find `eexec' keyword\n" ));
          error = FT_THROW( Invalid_File_Format );
          goto Exit;
        }
      }

      /* check whether `eexec' was real -- it could be in a comment */
      /* or string (as e.g. in u003043t.gsf from ghostscript)       */

      parser->root.cursor = parser->base_dict;
      /* set limit to `eexec' + whitespace + 4 characters */
      parser->root.limit  = cur + 10;

      cur   = parser->root.cursor;
      limit = parser->root.limit;

      while ( cur < limit )
      {
        if ( *cur == 'e' && ft_strncmp( (char*)cur, "eexec", 5 ) == 0 )
          goto Found;

        T1_Skip_PS_Token( parser );
        if ( parser->root.error )
          break;
        T1_Skip_Spaces  ( parser );
        cur = parser->root.cursor;
      }

      /* we haven't found the correct `eexec'; go back and continue */
      /* searching                                                  */

      cur   = limit;
      limit = parser->base_dict + parser->base_len;
      goto Again;

      /* now determine where to write the _encrypted_ binary private  */
      /* dictionary.  We overwrite the base dictionary for disk-based */
      /* resources and allocate a new block otherwise                 */

    Found:
      parser->root.limit = parser->base_dict + parser->base_len;

      T1_Skip_PS_Token( parser );
      cur   = parser->root.cursor;
      limit = parser->root.limit;

      /* according to the Type1 spec, the first cipher byte must not be  */
      /* an ASCII whitespace character code (blank, tab, carriage return */
      /* or line feed).  We have seen Type 1 fonts with two line feed    */
      /* characters...  So skip now all whitespace character codes.      */
      /* SumatraPDF: stop at \r if it's not used for EOL - cf. https://code.google.com/p/sumatrapdf/issues/detail?id=2408 */
      c = !memchr(cur, '\n', limit - cur) || memchr(cur, '\n', limit - cur) > memchr(cur, '\r', limit - cur);
      while ( cur < limit       &&
              ( *cur == ' '  ||
                *cur == '\t' ||
                ( c && *cur == '\r' ) ||
                *cur == '\n' ) )
        ++cur;
      if ( cur >= limit )
      {
        FT_ERROR(( "T1_Get_Private_Dict:"
                   " `eexec' not properly terminated\n" ));
        error = FT_THROW( Invalid_File_Format );
        goto Exit;
      }

      size = (FT_ULong)( parser->base_len - ( cur - parser->base_dict ) );

      if ( parser->in_memory )
      {
        /* note that we allocate one more byte to put a terminating `0' */
        if ( FT_ALLOC( parser->private_dict, size + 1 ) )
          goto Fail;
        parser->private_len = size;
      }
      else
      {
        parser->single_block = 1;
        parser->private_dict = parser->base_dict;
        parser->private_len  = size;
        parser->base_dict    = 0;
        parser->base_len     = 0;
      }

      /* now determine whether the private dictionary is encoded in binary */
      /* or hexadecimal ASCII format -- decode it accordingly              */

      /* we need to access the next 4 bytes (after the final whitespace */
      /* following the `eexec' keyword); if they all are hexadecimal    */
      /* digits, then we have a case of ASCII storage                   */

      if ( cur + 3 < limit                                &&
           ft_isxdigit( cur[0] ) && ft_isxdigit( cur[1] ) &&
           ft_isxdigit( cur[2] ) && ft_isxdigit( cur[3] ) )
      {
        /* ASCII hexadecimal encoding */
        FT_Long  len;


        parser->root.cursor = cur;
        (void)psaux->ps_parser_funcs->to_bytes( &parser->root,
                                                parser->private_dict,
                                                parser->private_len,
                                                &len,
                                                0 );
        parser->private_len = len;

        /* put a safeguard */
        parser->private_dict[len] = '\0';
      }
      else
        /* binary encoding -- copy the private dict */
        FT_MEM_MOVE( parser->private_dict, cur, size );
    }

    /* we now decrypt the encoded binary private dictionary */
    psaux->t1_decrypt( parser->private_dict, parser->private_len, 55665U );

    if ( parser->private_len < 4 )
    {
      FT_ERROR(( "T1_Get_Private_Dict:"
                 " invalid private dictionary section\n" ));
      error = FT_THROW( Invalid_File_Format );
      goto Fail;
    }

    /* replace the four random bytes at the beginning with whitespace */
    parser->private_dict[0] = ' ';
    parser->private_dict[1] = ' ';
    parser->private_dict[2] = ' ';
    parser->private_dict[3] = ' ';

    parser->root.base   = parser->private_dict;
    parser->root.cursor = parser->private_dict;
    parser->root.limit  = parser->root.cursor + parser->private_len;

  Fail:
  Exit:
    return error;
  }
  T1_New_Parser( T1_Parser      parser,
                 FT_Stream      stream,
                 FT_Memory      memory,
                 PSAux_Service  psaux )
  {
    FT_Error   error;
    FT_UShort  tag;
    FT_ULong   size;


    psaux->ps_parser_funcs->init( &parser->root, 0, 0, memory );

    parser->stream       = stream;
    parser->base_len     = 0;
    parser->base_dict    = 0;
    parser->private_len  = 0;
    parser->private_dict = 0;
    parser->in_pfb       = 0;
    parser->in_memory    = 0;
    parser->single_block = 0;

    /* check the header format */
    error = check_type1_format( stream, "%!PS-AdobeFont", 14 );
    if ( error )
    {
      if ( FT_ERR_NEQ( error, Unknown_File_Format ) )
        goto Exit;

      error = check_type1_format( stream, "%!FontType", 10 );
      if ( error )
      {
        FT_TRACE2(( "  not a Type 1 font\n" ));
        goto Exit;
      }
    }

    /******************************************************************/
    /*                                                                */
    /* Here a short summary of what is going on:                      */
    /*                                                                */
    /*   When creating a new Type 1 parser, we try to locate and load */
    /*   the base dictionary if this is possible (i.e., for PFB       */
    /*   files).  Otherwise, we load the whole font into memory.      */
    /*                                                                */
    /*   When `loading' the base dictionary, we only setup pointers   */
    /*   in the case of a memory-based stream.  Otherwise, we         */
    /*   allocate and load the base dictionary in it.                 */
    /*                                                                */
    /*   parser->in_pfb is set if we are in a binary (`.pfb') font.   */
    /*   parser->in_memory is set if we have a memory stream.         */
    /*                                                                */

    /* try to compute the size of the base dictionary;     */
    /* look for a Postscript binary file tag, i.e., 0x8001 */
    if ( FT_STREAM_SEEK( 0L ) )
      goto Exit;

    error = read_pfb_tag( stream, &tag, &size );
    if ( error )
      goto Exit;

    if ( tag != 0x8001U )
    {
      /* assume that this is a PFA file for now; an error will */
      /* be produced later when more things are checked        */
      if ( FT_STREAM_SEEK( 0L ) )
        goto Exit;
      size = stream->size;
    }
    else
      parser->in_pfb = 1;

    /* now, try to load `size' bytes of the `base' dictionary we */
    /* found previously                                          */

    /* if it is a memory-based resource, set up pointers */
    if ( !stream->read )
    {
      parser->base_dict = (FT_Byte*)stream->base + stream->pos;
      parser->base_len  = size;
      parser->in_memory = 1;

      /* check that the `size' field is valid */
      if ( FT_STREAM_SKIP( size ) )
        goto Exit;
    }
    else
    {
      /* read segment in memory -- this is clumsy, but so does the format */
      if ( FT_ALLOC( parser->base_dict, size )       ||
           FT_STREAM_READ( parser->base_dict, size ) )
        goto Exit;
      parser->base_len = size;
    }

    parser->root.base   = parser->base_dict;
    parser->root.cursor = parser->base_dict;
    parser->root.limit  = parser->root.cursor + parser->base_len;

  Exit:
    if ( error && !parser->in_memory )
      FT_FREE( parser->base_dict );

    return error;
  }
Ejemplo n.º 5
0
Archivo: t1parse.c Proyecto: 8l/inferno
  T1_Get_Private_Dict( T1_Parser      parser,
                       PSAux_Service  psaux )
  {
    FT_Stream  stream = parser->stream;
    FT_Memory  memory = parser->root.memory;
    FT_Error   error  = 0;
    FT_Long    size;


    if ( parser->in_pfb )
    {
      /* in the case of the PFB format, the private dictionary can be  */
      /* made of several segments.  We thus first read the number of   */
      /* segments to compute the total size of the private dictionary  */
      /* then re-read them into memory.                                */
      FT_Long    start_pos = FT_STREAM_POS();
      FT_UShort  tag;


      parser->private_len = 0;
      for (;;)
      {
        error = read_pfb_tag( stream, &tag, &size );
        if ( error )
          goto Fail;

        if ( tag != 0x8002U )
          break;

        parser->private_len += size;

        if ( FT_STREAM_SKIP( size ) )
          goto Fail;
      }

      /* Check that we have a private dictionary there */
      /* and allocate private dictionary buffer        */
      if ( parser->private_len == 0 )
      {
        FT_ERROR(( "T1_Get_Private_Dict:" ));
        FT_ERROR(( " invalid private dictionary section\n" ));
        error = T1_Err_Invalid_File_Format;
        goto Fail;
      }

      if ( FT_STREAM_SEEK( start_pos )                             ||
           FT_ALLOC( parser->private_dict, parser->private_len ) )
        goto Fail;

      parser->private_len = 0;
      for (;;)
      {
        error = read_pfb_tag( stream, &tag, &size );
        if ( error || tag != 0x8002U )
        {
          error = T1_Err_Ok;
          break;
        }

        if ( FT_STREAM_READ( parser->private_dict + parser->private_len, size ) )
          goto Fail;

        parser->private_len += size;
      }
    }
    else
    {
      /* we have already `loaded' the whole PFA font file into memory; */
      /* if this is a memory resource, allocate a new block to hold    */
      /* the private dict. Otherwise, simply overwrite into the base   */
      /* dictionary block in the heap.                                 */

      /* first of all, look at the `eexec' keyword */
      FT_Byte*  cur   = parser->base_dict;
      FT_Byte*  limit = cur + parser->base_len;
      FT_Byte   c;


      for (;;)
      {
        c = cur[0];
        if ( c == 'e' && cur + 9 < limit )  /* 9 = 5 letters for `eexec' + */
                                            /* newline + 4 chars           */
        {
          if ( cur[1] == 'e' && cur[2] == 'x' &&
               cur[3] == 'e' && cur[4] == 'c' )
          {
            cur += 6; /* we skip the newling after the `eexec' */

            /* XXX: Some fonts use DOS-linefeeds, i.e. \r\n; we need to */
            /*      skip the extra \n if we find it                     */
            if ( cur[0] == '\n' )
              cur++;

            break;
          }
        }
        cur++;
        if ( cur >= limit )
        {
          FT_ERROR(( "T1_Get_Private_Dict:" ));
          FT_ERROR(( " could not find `eexec' keyword\n" ));
          error = T1_Err_Invalid_File_Format;
          goto Exit;
        }
      }

      /* now determine where to write the _encrypted_ binary private  */
      /* dictionary.  We overwrite the base dictionary for disk-based */
      /* resources and allocate a new block otherwise                 */

      size = (FT_Long)( parser->base_len - ( cur - parser->base_dict ) );

      if ( parser->in_memory )
      {
        /* note that we allocate one more byte to put a terminating `0' */
        if ( FT_ALLOC( parser->private_dict, size + 1 ) )
          goto Fail;
        parser->private_len = size;
      }
      else
      {
        parser->single_block = 1;
        parser->private_dict = parser->base_dict;
        parser->private_len  = size;
        parser->base_dict    = 0;
        parser->base_len     = 0;
      }

      /* now determine whether the private dictionary is encoded in binary */
      /* or hexadecimal ASCII format -- decode it accordingly              */

      /* we need to access the next 4 bytes (after the final \r following */
      /* the `eexec' keyword); if they all are hexadecimal digits, then   */
      /* we have a case of ASCII storage                                  */

      if ( ( hexa_value( cur[0] ) | hexa_value( cur[1] ) |
             hexa_value( cur[2] ) | hexa_value( cur[3] ) ) < 0 )

        /* binary encoding -- `simply' copy the private dict */
        FT_MEM_COPY( parser->private_dict, cur, size );

      else
      {
        /* ASCII hexadecimal encoding */

        FT_Byte*  write;
        FT_Int    count;


        write = parser->private_dict;
        count = 0;

        for ( ;cur < limit; cur++ )
        {
          int  hex1;


          /* check for newline */
          if ( cur[0] == '\r' || cur[0] == '\n' )
            continue;

          /* exit if we have a non-hexadecimal digit that isn't a newline */
          hex1 = hexa_value( cur[0] );
          if ( hex1 < 0 || cur + 1 >= limit )
            break;

          /* otherwise, store byte */
          *write++ = (FT_Byte)( ( hex1 << 4 ) | hexa_value( cur[1] ) );
          count++;
          cur++;
        }

        /* put a safeguard */
        parser->private_len = write - parser->private_dict;
        *write++ = 0;
      }
    }

    /* we now decrypt the encoded binary private dictionary */
    psaux->t1_decrypt( parser->private_dict, parser->private_len, 55665U );
    parser->root.base   = parser->private_dict;
    parser->root.cursor = parser->private_dict;
    parser->root.limit  = parser->root.cursor + parser->private_len;

  Fail:
  Exit:
    return error;
  }