Edit
kc3-lang/freetype/src/sfnt/sfwoff2.c
Werner Lemberg
- src/sfnt/sfwoff2.c
-
/**************************************************************************** * * sfwoff2.c * * WOFF2 format management (base). * * Copyright (C) 2019-2020 by * Nikhil Ramakrishnan, David Turner, Robert Wilhelm, and Werner Lemberg. * * This file is part of the FreeType project, and may only be used, * modified, and distributed under the terms of the FreeType project * license, LICENSE.TXT. By continuing to use, modify, or distribute * this file you indicate that you have read the license and * understand and accept it fully. * */ #include "sfwoff2.h" #include "woff2tags.h" #include <freetype/tttags.h> #include <freetype/internal/ftdebug.h> #include <freetype/internal/ftstream.h> #ifdef FT_CONFIG_OPTION_USE_BROTLI #include <brotli/decode.h> #endif /************************************************************************** * * The macro FT_COMPONENT is used in trace mode. It is an implicit * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log * messages during execution. */ #undef FT_COMPONENT #define FT_COMPONENT sfwoff2 #define READ_255USHORT( var ) FT_SET_ERROR( Read255UShort( stream, &var ) ) #define READ_BASE128( var ) FT_SET_ERROR( ReadBase128( stream, &var ) ) #define ROUND4( var ) ( ( var + 3 ) & ~3 ) #define WRITE_USHORT( p, v ) \ do \ { \ *(p)++ = (FT_Byte)( (v) >> 8 ); \ *(p)++ = (FT_Byte)( (v) >> 0 ); \ \ } while ( 0 ) #define WRITE_ULONG( p, v ) \ do \ { \ *(p)++ = (FT_Byte)( (v) >> 24 ); \ *(p)++ = (FT_Byte)( (v) >> 16 ); \ *(p)++ = (FT_Byte)( (v) >> 8 ); \ *(p)++ = (FT_Byte)( (v) >> 0 ); \ \ } while ( 0 ) #define WRITE_SHORT( p, v ) \ do \ { \ *(p)++ = ( (v) >> 8 ); \ *(p)++ = ( (v) >> 0 ); \ \ } while ( 0 ) #define WRITE_SFNT_BUF( buf, s ) \ write_buf( &sfnt, sfnt_size, &dest_offset, buf, s, memory ) #define WRITE_SFNT_BUF_AT( offset, buf, s ) \ write_buf( &sfnt, sfnt_size, &offset, buf, s, memory ) #define N_CONTOUR_STREAM 0 #define N_POINTS_STREAM 1 #define FLAG_STREAM 2 #define GLYPH_STREAM 3 #define COMPOSITE_STREAM 4 #define BBOX_STREAM 5 #define INSTRUCTION_STREAM 6 static void stream_close( FT_Stream stream ) { FT_Memory memory = stream->memory; FT_FREE( stream->base ); stream->size = 0; stream->base = NULL; stream->close = NULL; } FT_CALLBACK_DEF( int ) compare_tags( const void* a, const void* b ) { WOFF2_Table table1 = *(WOFF2_Table*)a; WOFF2_Table table2 = *(WOFF2_Table*)b; FT_ULong tag1 = table1->Tag; FT_ULong tag2 = table2->Tag; if ( tag1 > tag2 ) return 1; else if ( tag1 < tag2 ) return -1; else return 0; } static FT_Error Read255UShort( FT_Stream stream, FT_UShort* value ) { static const FT_Int oneMoreByteCode1 = 255; static const FT_Int oneMoreByteCode2 = 254; static const FT_Int wordCode = 253; static const FT_Int lowestUCode = 253; FT_Error error = FT_Err_Ok; FT_Byte code; FT_Byte result_byte = 0; FT_UShort result_short = 0; if ( FT_READ_BYTE( code ) ) return error; if ( code == wordCode ) { /* Read next two bytes and store `FT_UShort' value. */ if ( FT_READ_USHORT( result_short ) ) return error; *value = result_short; return FT_Err_Ok; } else if ( code == oneMoreByteCode1 ) { if ( FT_READ_BYTE( result_byte ) ) return error; *value = result_byte + lowestUCode; return FT_Err_Ok; } else if ( code == oneMoreByteCode2 ) { if ( FT_READ_BYTE( result_byte ) ) return error; *value = result_byte + lowestUCode * 2; return FT_Err_Ok; } else { *value = code; return FT_Err_Ok; } } static FT_Error ReadBase128( FT_Stream stream, FT_ULong* value ) { FT_ULong result = 0; FT_Int i; FT_Byte code; FT_Error error = FT_Err_Ok; for ( i = 0; i < 5; ++i ) { code = 0; if ( FT_READ_BYTE( code ) ) return error; /* Leading zeros are invalid. */ if ( i == 0 && code == 0x80 ) return FT_THROW( Invalid_Table ); /* If any of top seven bits are set then we're about to overflow. */ if ( result & 0xfe000000 ) return FT_THROW( Invalid_Table ); result = ( result << 7 ) | ( code & 0x7f ); /* Spin until most significant bit of data byte is false. */ if ( ( code & 0x80 ) == 0 ) { *value = result; return FT_Err_Ok; } } /* Make sure not to exceed the size bound. */ return FT_THROW( Invalid_Table ); } /* Extend memory of `dst_bytes' buffer and copy data from `src'. */ static FT_Error write_buf( FT_Byte** dst_bytes, FT_ULong* dst_size, FT_ULong* offset, FT_Byte* src, FT_ULong size, FT_Memory memory ) { FT_Error error = FT_Err_Ok; /* We are reallocating memory for `dst', so its pointer may change. */ FT_Byte* dst = *dst_bytes; /* Check whether we are within limits. */ if ( ( *offset + size ) > WOFF2_DEFAULT_MAX_SIZE ) return FT_THROW( Array_Too_Large ); /* Reallocate `dst'. */ if ( ( *offset + size ) > *dst_size ) { FT_TRACE6(( "Reallocating %lu to %lu.\n", *dst_size, (*offset + size) )); if ( FT_REALLOC( dst, (FT_ULong)( *dst_size ), (FT_ULong)( *offset + size ) ) ) goto Exit; *dst_size = *offset + size; } /* Copy data. */ ft_memcpy( dst + *offset, src, size ); *offset += size; /* Set pointer of `dst' to its correct value. */ *dst_bytes = dst; Exit: return error; } /* Pad buffer to closest multiple of 4. */ static FT_Error pad4( FT_Byte** sfnt_bytes, FT_ULong* sfnt_size, FT_ULong* out_offset, FT_Memory memory ) { FT_Byte* sfnt = *sfnt_bytes; FT_ULong dest_offset = *out_offset; FT_Byte zeroes[] = { 0, 0, 0 }; FT_ULong pad_bytes; if ( dest_offset + 3 < dest_offset ) return FT_THROW( Invalid_Table ); pad_bytes = ROUND4( dest_offset ) - dest_offset; if ( pad_bytes > 0 ) { if ( WRITE_SFNT_BUF( &zeroes[0], pad_bytes ) ) return FT_THROW( Invalid_Table ); } *sfnt_bytes = sfnt; *out_offset = dest_offset; return FT_Err_Ok; } /* Calculate table checksum of `buf'. */ static FT_Long compute_ULong_sum( FT_Byte* buf, FT_ULong size ) { FT_ULong checksum = 0; FT_ULong aligned_size = size & ~3; FT_ULong i; FT_ULong v; for ( i = 0; i < aligned_size; i += 4 ) checksum += ( (FT_ULong)buf[i ] << 24 ) | ( (FT_ULong)buf[i + 1] << 16 ) | ( (FT_ULong)buf[i + 2] << 8 ) | ( (FT_ULong)buf[i + 3] << 0 ); /* If size is not aligned to 4, treat as if it is padded with 0s. */ if ( size != aligned_size ) { v = 0; for ( i = aligned_size ; i < size; ++i ) v |= (FT_ULong)buf[i] << ( 24 - 8 * ( i & 3 ) ); checksum += v; } return checksum; } static FT_Error woff2_decompress( FT_Byte* dst, FT_ULong dst_size, const FT_Byte* src, FT_ULong src_size ) { #ifdef FT_CONFIG_OPTION_USE_BROTLI FT_ULong uncompressed_size = dst_size; BrotliDecoderResult result; result = BrotliDecoderDecompress( src_size, src, &uncompressed_size, dst ); if ( result != BROTLI_DECODER_RESULT_SUCCESS || uncompressed_size != dst_size ) { FT_ERROR(( "woff2_decompress: Stream length mismatch.\n" )); return FT_THROW( Invalid_Table ); } FT_TRACE2(( "woff2_decompress: Brotli stream decompressed.\n" )); return FT_Err_Ok; #else /* !FT_CONFIG_OPTION_USE_BROTLI */ FT_ERROR(( "woff2_decompress: Brotli support not available.\n" )); return FT_THROW( Unimplemented_Feature ); #endif /* !FT_CONFIG_OPTION_USE_BROTLI */ } static WOFF2_Table find_table( WOFF2_Table* tables, FT_UShort num_tables, FT_ULong tag ) { FT_Int i; for ( i = 0; i < num_tables; i++ ) { if ( tables[i]->Tag == tag ) return tables[i]; } return NULL; } /* Read `numberOfHMetrics' field from `hhea' table. */ static FT_Error read_num_hmetrics( FT_Stream stream, FT_UShort* num_hmetrics ) { FT_Error error = FT_Err_Ok; FT_UShort num_metrics; if ( FT_STREAM_SKIP( 34 ) ) return FT_THROW( Invalid_Table ); if ( FT_READ_USHORT( num_metrics ) ) return FT_THROW( Invalid_Table ); *num_hmetrics = num_metrics; return error; } /* An auxiliary function for overflow-safe addition. */ static FT_Int with_sign( FT_Byte flag, FT_Int base_val ) { /* Precondition: 0 <= base_val < 65536 (to avoid overflow). */ return ( flag & 1 ) ? base_val : -base_val; } /* An auxiliary function for overflow-safe addition. */ static FT_Int safe_int_addition( FT_Int a, FT_Int b, FT_Int* result ) { if ( ( ( a > 0 ) && ( b > FT_INT_MAX - a ) ) || ( ( a < 0 ) && ( b < FT_INT_MIN - a ) ) ) return FT_THROW( Invalid_Table ); *result = a + b; return FT_Err_Ok; } /* * Decode variable-length (flag, xCoordinate, yCoordinate) triplet for a * simple glyph. See * * https://www.w3.org/TR/WOFF2/#triplet_decoding */ static FT_Error triplet_decode( const FT_Byte* flags_in, const FT_Byte* in, FT_ULong in_size, FT_ULong n_points, WOFF2_Point result, FT_ULong* in_bytes_used ) { FT_Int x = 0; FT_Int y = 0; FT_Int dx; FT_Int dy; FT_Int b0, b1, b2; FT_ULong triplet_index = 0; FT_ULong data_bytes; FT_UInt i; if ( n_points > in_size ) return FT_THROW( Invalid_Table ); for ( i = 0; i < n_points; ++i ) { FT_Byte flag = flags_in[i]; FT_Bool on_curve = !( flag >> 7 ); flag &= 0x7f; if ( flag < 84 ) data_bytes = 1; else if ( flag < 120 ) data_bytes = 2; else if ( flag < 124 ) data_bytes = 3; else data_bytes = 4; /* Overflow checks */ if ( triplet_index + data_bytes > in_size || triplet_index + data_bytes < triplet_index ) return FT_THROW( Invalid_Table ); if ( flag < 10 ) { dx = 0; dy = with_sign( flag, ( ( flag & 14 ) << 7 ) + in[triplet_index] ); } else if ( flag < 20 ) { dx = with_sign( flag, ( ( ( flag - 10 ) & 14 ) << 7 ) + in[triplet_index] ); dy = 0; } else if ( flag < 84 ) { b0 = flag - 20; b1 = in[triplet_index]; dx = with_sign( flag, 1 + ( b0 & 0x30 ) + ( b1 >> 4 ) ); dy = with_sign( flag >> 1, 1 + ( ( b0 & 0x0c ) << 2 ) + ( b1 & 0x0f ) ); } else if ( flag < 120 ) { b0 = flag - 84; dx = with_sign( flag, 1 + ( ( b0 / 12 ) << 8 ) + in[triplet_index] ); dy = with_sign( flag >> 1, 1 + ( ( ( b0 % 12 ) >> 2 ) << 8 ) + in[triplet_index + 1] ); } else if ( flag < 124 ) { b2 = in[triplet_index + 1]; dx = with_sign( flag, ( in[triplet_index] << 4 ) + ( b2 >> 4 ) ); dy = with_sign( flag >> 1, ( ( b2 & 0x0f ) << 8 ) + in[triplet_index + 2] ); } else { dx = with_sign( flag, ( in[triplet_index] << 8 ) + in[triplet_index + 1] ); dy = with_sign( flag >> 1, ( in[triplet_index + 2] << 8 ) + in[triplet_index + 3] ); } triplet_index += data_bytes; if ( safe_int_addition( x, dx, &x ) ) return FT_THROW( Invalid_Table ); if ( safe_int_addition( y, dy, &y ) ) return FT_THROW( Invalid_Table ); result[i].x = x; result[i].y = y; result[i].on_curve = on_curve; } *in_bytes_used = triplet_index; return FT_Err_Ok; } /* Store decoded points in glyph buffer. */ static FT_Error store_points( FT_ULong n_points, const WOFF2_Point points, FT_UShort n_contours, FT_UShort instruction_len, FT_Byte* dst, FT_ULong dst_size, FT_ULong* glyph_size ) { FT_UInt flag_offset = 10 + ( 2 * n_contours ) + 2 + instruction_len; FT_Int last_flag = -1; FT_Int repeat_count = 0; FT_Int last_x = 0; FT_Int last_y = 0; FT_UInt x_bytes = 0; FT_UInt y_bytes = 0; FT_UInt xy_bytes; FT_UInt i; FT_UInt x_offset; FT_UInt y_offset; FT_Byte* pointer; for ( i = 0; i < n_points; ++i ) { const WOFF2_PointRec point = points[i]; FT_Int flag = point.on_curve ? GLYF_ON_CURVE : 0; FT_Int dx = point.x - last_x; FT_Int dy = point.y - last_y; if ( dx == 0 ) flag |= GLYF_THIS_X_IS_SAME; else if ( dx > -256 && dx < 256 ) { flag |= GLYF_X_SHORT | ( dx > 0 ? GLYF_THIS_X_IS_SAME : 0 ); x_bytes += 1; } else x_bytes += 2; if ( dy == 0 ) flag |= GLYF_THIS_Y_IS_SAME; else if ( dy > -256 && dy < 256 ) { flag |= GLYF_Y_SHORT | ( dy > 0 ? GLYF_THIS_Y_IS_SAME : 0 ); y_bytes += 1; } else y_bytes += 2; if ( flag == last_flag && repeat_count != 255 ) { dst[flag_offset - 1] |= GLYF_REPEAT; repeat_count++; } else { if ( repeat_count != 0 ) { if ( flag_offset >= dst_size ) return FT_THROW( Invalid_Table ); dst[flag_offset++] = repeat_count; } if ( flag_offset >= dst_size ) return FT_THROW( Invalid_Table ); dst[flag_offset++] = flag; repeat_count = 0; } last_x = point.x; last_y = point.y; last_flag = flag; } if ( repeat_count != 0 ) { if ( flag_offset >= dst_size ) return FT_THROW( Invalid_Table ); dst[flag_offset++] = repeat_count; } xy_bytes = x_bytes + y_bytes; if ( xy_bytes < x_bytes || flag_offset + xy_bytes < flag_offset || flag_offset + xy_bytes > dst_size ) return FT_THROW( Invalid_Table ); x_offset = flag_offset; y_offset = flag_offset + x_bytes; last_x = 0; last_y = 0; for ( i = 0; i < n_points; ++i ) { FT_Int dx = points[i].x - last_x; FT_Int dy = points[i].y - last_y; if ( dx == 0 ) ; else if ( dx > -256 && dx < 256 ) dst[x_offset++] = FT_ABS( dx ); else { pointer = dst + x_offset; WRITE_SHORT( pointer, dx ); x_offset += 2; } last_x += dx; if ( dy == 0 ) ; else if ( dy > -256 && dy < 256 ) dst[y_offset++] = FT_ABS( dy ); else { pointer = dst + y_offset; WRITE_SHORT( pointer, dy ); y_offset += 2; } last_y += dy; } *glyph_size = y_offset; return FT_Err_Ok; } static void compute_bbox( FT_ULong n_points, const WOFF2_Point points, FT_Byte* dst, FT_UShort* src_x_min ) { FT_Int x_min = 0; FT_Int y_min = 0; FT_Int x_max = 0; FT_Int y_max = 0; FT_UInt i; FT_ULong offset; FT_Byte* pointer; if ( n_points > 0 ) { x_min = points[0].x; y_min = points[0].y; x_max = points[0].x; y_max = points[0].y; } for ( i = 1; i < n_points; ++i ) { FT_Int x = points[i].x; FT_Int y = points[i].y; x_min = FT_MIN( x, x_min ); y_min = FT_MIN( y, y_min ); x_max = FT_MAX( x, x_max ); y_max = FT_MAX( y, y_max ); } /* Write values to `glyf' record. */ offset = 2; pointer = dst + offset; WRITE_SHORT( pointer, x_min ); WRITE_SHORT( pointer, y_min ); WRITE_SHORT( pointer, x_max ); WRITE_SHORT( pointer, y_max ); *src_x_min = (FT_UShort)x_min; } static FT_Error compositeGlyph_size( FT_Stream stream, FT_ULong offset, FT_ULong* size, FT_Bool* have_instructions ) { FT_Error error = FT_Err_Ok; FT_ULong start_offset = offset; FT_Bool we_have_inst = FALSE; FT_UShort flags = FLAG_MORE_COMPONENTS; if ( FT_STREAM_SEEK( start_offset ) ) goto Exit; while ( flags & FLAG_MORE_COMPONENTS ) { FT_ULong arg_size; if ( FT_READ_USHORT( flags ) ) goto Exit; we_have_inst |= ( flags & FLAG_WE_HAVE_INSTRUCTIONS ) != 0; /* glyph index */ arg_size = 2; if ( flags & FLAG_ARG_1_AND_2_ARE_WORDS ) arg_size += 4; else arg_size += 2; if ( flags & FLAG_WE_HAVE_A_SCALE ) arg_size += 2; else if ( flags & FLAG_WE_HAVE_AN_X_AND_Y_SCALE ) arg_size += 4; else if ( flags & FLAG_WE_HAVE_A_TWO_BY_TWO ) arg_size += 8; if ( FT_STREAM_SKIP( arg_size ) ) goto Exit; } *size = FT_STREAM_POS() - start_offset; *have_instructions = we_have_inst; Exit: return error; } /* Store loca values (provided by `reconstruct_glyf') to output stream. */ static FT_Error store_loca( FT_ULong* loca_values, FT_ULong loca_values_size, FT_UShort index_format, FT_ULong* checksum, FT_Byte** sfnt_bytes, FT_ULong* sfnt_size, FT_ULong* out_offset, FT_Memory memory ) { FT_Error error = FT_Err_Ok; FT_Byte* sfnt = *sfnt_bytes; FT_ULong dest_offset = *out_offset; FT_Byte* loca_buf = NULL; FT_Byte* dst = NULL; FT_UInt i = 0; FT_ULong loca_buf_size; const FT_ULong offset_size = index_format ? 4 : 2; if ( ( loca_values_size << 2 ) >> 2 != loca_values_size ) goto Fail; loca_buf_size = loca_values_size * offset_size; if ( FT_NEW_ARRAY( loca_buf, loca_buf_size ) ) goto Fail; dst = loca_buf; for ( i = 0; i < loca_values_size; i++ ) { FT_ULong value = loca_values[i]; if ( index_format ) WRITE_ULONG( dst, value ); else WRITE_USHORT( dst, ( value >> 1 ) ); } *checksum = compute_ULong_sum( loca_buf, loca_buf_size ); /* Write `loca' table to sfnt buffer. */ if ( WRITE_SFNT_BUF( loca_buf, loca_buf_size ) ) goto Fail; /* Set pointer `sfnt_bytes' to its correct value. */ *sfnt_bytes = sfnt; *out_offset = dest_offset; FT_FREE( loca_buf ); return error; Fail: if ( !error ) error = FT_THROW( Invalid_Table ); FT_FREE( loca_buf ); return error; } static FT_Error reconstruct_glyf( FT_Stream stream, FT_ULong* glyf_checksum, FT_ULong* loca_checksum, FT_Byte** sfnt_bytes, FT_ULong* sfnt_size, FT_ULong* out_offset, WOFF2_Info info, FT_Memory memory ) { FT_Error error = FT_Err_Ok; FT_Byte* sfnt = *sfnt_bytes; /* current position in stream */ const FT_ULong pos = FT_STREAM_POS(); FT_UInt num_substreams = 7; FT_UShort num_glyphs; FT_UShort index_format; FT_ULong expected_loca_length; FT_UInt offset; FT_UInt i; FT_ULong points_size; FT_ULong bitmap_length; FT_ULong glyph_buf_size; FT_ULong bbox_bitmap_offset; const FT_ULong glyf_start = *out_offset; FT_ULong dest_offset = *out_offset; WOFF2_Substream substreams = NULL; FT_ULong* loca_values = NULL; FT_UShort* n_points_arr = NULL; FT_Byte* glyph_buf = NULL; WOFF2_Point points = NULL; if ( FT_NEW_ARRAY( substreams, num_substreams ) ) goto Fail; if ( FT_STREAM_SKIP( 4 ) ) goto Fail; if ( FT_READ_USHORT( num_glyphs ) ) goto Fail; if ( FT_READ_USHORT( index_format ) ) goto Fail; FT_TRACE4(( "num_glyphs = %u; index_format = %u\n", num_glyphs, index_format )); info->num_glyphs = num_glyphs; /* Calculate expected length of loca and compare. */ /* See https://www.w3.org/TR/WOFF2/#conform-mustRejectLoca */ /* index_format = 0 => Short version `loca'. */ /* index_format = 1 => Long version `loca'. */ expected_loca_length = ( index_format ? 4 : 2 ) * ( (FT_ULong)num_glyphs + 1 ); if ( info->loca_table->dst_length != expected_loca_length ) goto Fail; offset = ( 2 + num_substreams ) * 4; if ( offset > info->glyf_table->TransformLength ) goto Fail; for ( i = 0; i < num_substreams; ++i ) { FT_ULong substream_size; if ( FT_READ_ULONG( substream_size ) ) goto Fail; if ( substream_size > info->glyf_table->TransformLength - offset ) goto Fail; substreams[i].start = pos + offset; substreams[i].offset = pos + offset; substreams[i].size = substream_size; FT_TRACE5(( " Substream %d: offset = %lu; size = %lu;\n", i, substreams[i].offset, substreams[i].size )); offset += substream_size; } if ( FT_NEW_ARRAY( loca_values, num_glyphs + 1 ) ) goto Fail; points_size = 0; bbox_bitmap_offset = substreams[BBOX_STREAM].offset; /* Size of bboxBitmap = 4 * floor((numGlyphs + 31) / 32) */ bitmap_length = ( ( num_glyphs + 31 ) >> 5 ) << 2; substreams[BBOX_STREAM].offset += bitmap_length; glyph_buf_size = WOFF2_DEFAULT_GLYPH_BUF; if ( FT_NEW_ARRAY( glyph_buf, glyph_buf_size ) ) goto Fail; if ( FT_NEW_ARRAY( info->x_mins, num_glyphs ) ) goto Fail; for ( i = 0; i < num_glyphs; ++i ) { FT_ULong glyph_size = 0; FT_UShort n_contours = 0; FT_Bool have_bbox = FALSE; FT_Byte bbox_bitmap; FT_ULong bbox_offset; FT_UShort x_min = 0; /* Set `have_bbox'. */ bbox_offset = bbox_bitmap_offset + ( i >> 3 ); if ( FT_STREAM_SEEK( bbox_offset ) || FT_READ_BYTE( bbox_bitmap ) ) goto Fail; if ( bbox_bitmap & ( 0x80 >> ( i & 7 ) ) ) have_bbox = TRUE; /* Read value from `nContourStream'. */ if ( FT_STREAM_SEEK( substreams[N_CONTOUR_STREAM].offset ) || FT_READ_USHORT( n_contours ) ) goto Fail; substreams[N_CONTOUR_STREAM].offset += 2; if ( n_contours == 0xffff ) { /* composite glyph */ FT_Bool have_instructions = FALSE; FT_UShort instruction_size = 0; FT_ULong composite_size; FT_ULong size_needed; FT_Byte* pointer = NULL; /* Composite glyphs must have explicit bbox. */ if ( !have_bbox ) goto Fail; if ( compositeGlyph_size( stream, substreams[COMPOSITE_STREAM].offset, &composite_size, &have_instructions) ) goto Fail; if ( have_instructions ) { if ( FT_STREAM_SEEK( substreams[GLYPH_STREAM].offset ) || READ_255USHORT( instruction_size ) ) goto Fail; substreams[GLYPH_STREAM].offset = FT_STREAM_POS(); } size_needed = 12 + composite_size + instruction_size; if ( glyph_buf_size < size_needed ) { if ( FT_RENEW_ARRAY( glyph_buf, glyph_buf_size, size_needed ) ) goto Fail; glyph_buf_size = size_needed; } pointer = glyph_buf + glyph_size; WRITE_USHORT( pointer, n_contours ); glyph_size += 2; /* Read x_min for current glyph. */ if ( FT_STREAM_SEEK( substreams[BBOX_STREAM].offset ) || FT_READ_USHORT( x_min ) ) goto Fail; /* No increment here because we read again. */ if ( FT_STREAM_SEEK( substreams[BBOX_STREAM].offset ) || FT_STREAM_READ( glyph_buf + glyph_size, 8 ) ) goto Fail; substreams[BBOX_STREAM].offset += 8; glyph_size += 8; if ( FT_STREAM_SEEK( substreams[COMPOSITE_STREAM].offset ) || FT_STREAM_READ( glyph_buf + glyph_size, composite_size ) ) goto Fail; substreams[COMPOSITE_STREAM].offset += composite_size; glyph_size += composite_size; if ( have_instructions ) { pointer = glyph_buf + glyph_size; WRITE_USHORT( pointer, instruction_size ); glyph_size += 2; if ( FT_STREAM_SEEK( substreams[INSTRUCTION_STREAM].offset ) || FT_STREAM_READ( glyph_buf + glyph_size, instruction_size ) ) goto Fail; substreams[INSTRUCTION_STREAM].offset += instruction_size; glyph_size += instruction_size; } } else if ( n_contours > 0 ) { /* simple glyph */ FT_ULong total_n_points = 0; FT_UShort n_points_contour; FT_UInt j; FT_ULong flag_size; FT_ULong triplet_size; FT_ULong triplet_bytes_used; FT_Byte* flags_buf = NULL; FT_Byte* triplet_buf = NULL; FT_UShort instruction_size; FT_ULong size_needed; FT_Int end_point; FT_UInt contour_ix; FT_Byte* pointer = NULL; if ( FT_NEW_ARRAY( n_points_arr, n_contours ) ) goto Fail; if ( FT_STREAM_SEEK( substreams[N_POINTS_STREAM].offset ) ) goto Fail; for ( j = 0; j < n_contours; ++j ) { if ( READ_255USHORT( n_points_contour ) ) goto Fail; n_points_arr[j] = n_points_contour; /* Prevent negative/overflow. */ if ( total_n_points + n_points_contour < total_n_points ) goto Fail; total_n_points += n_points_contour; } substreams[N_POINTS_STREAM].offset = FT_STREAM_POS(); flag_size = total_n_points; if ( flag_size > substreams[FLAG_STREAM].size ) goto Fail; flags_buf = stream->base + substreams[FLAG_STREAM].offset; triplet_buf = stream->base + substreams[GLYPH_STREAM].offset; if ( substreams[GLYPH_STREAM].size < ( substreams[GLYPH_STREAM].offset - substreams[GLYPH_STREAM].start ) ) goto Fail; triplet_size = substreams[GLYPH_STREAM].size - ( substreams[GLYPH_STREAM].offset - substreams[GLYPH_STREAM].start ); triplet_bytes_used = 0; /* Create array to store point information. */ points_size = total_n_points; if ( FT_NEW_ARRAY( points, points_size ) ) goto Fail; if ( triplet_decode( flags_buf, triplet_buf, triplet_size, total_n_points, points, &triplet_bytes_used ) ) goto Fail; substreams[FLAG_STREAM].offset += flag_size; substreams[GLYPH_STREAM].offset += triplet_bytes_used; if ( FT_STREAM_SEEK( substreams[GLYPH_STREAM].offset ) || READ_255USHORT( instruction_size ) ) goto Fail; substreams[GLYPH_STREAM].offset = FT_STREAM_POS(); if ( total_n_points >= ( 1 << 27 ) ) goto Fail; size_needed = 12 + ( 2 * n_contours ) + ( 5 * total_n_points ) + instruction_size; if ( glyph_buf_size < size_needed ) { if ( FT_RENEW_ARRAY( glyph_buf, glyph_buf_size, size_needed ) ) goto Fail; glyph_buf_size = size_needed; } pointer = glyph_buf + glyph_size; WRITE_USHORT( pointer, n_contours ); glyph_size += 2; if ( have_bbox ) { /* Read x_min for current glyph. */ if ( FT_STREAM_SEEK( substreams[BBOX_STREAM].offset ) || FT_READ_USHORT( x_min ) ) goto Fail; /* No increment here because we read again. */ if ( FT_STREAM_SEEK( substreams[BBOX_STREAM].offset ) || FT_STREAM_READ( glyph_buf + glyph_size, 8 ) ) goto Fail; substreams[BBOX_STREAM].offset += 8; } else compute_bbox( total_n_points, points, glyph_buf, &x_min ); glyph_size = CONTOUR_OFFSET_END_POINT; pointer = glyph_buf + glyph_size; end_point = -1; for ( contour_ix = 0; contour_ix < n_contours; ++contour_ix ) { end_point += n_points_arr[contour_ix]; if ( end_point >= 65536 ) goto Fail; WRITE_SHORT( pointer, end_point ); glyph_size += 2; } WRITE_USHORT( pointer, instruction_size ); glyph_size += 2; if ( FT_STREAM_SEEK( substreams[INSTRUCTION_STREAM].offset ) || FT_STREAM_READ( glyph_buf + glyph_size, instruction_size ) ) goto Fail; substreams[INSTRUCTION_STREAM].offset += instruction_size; glyph_size += instruction_size; if ( store_points( total_n_points, points, n_contours, instruction_size, glyph_buf, glyph_buf_size, &glyph_size ) ) goto Fail; FT_FREE( points ); FT_FREE( n_points_arr ); } else { /* Empty glyph. */ /* Must not have a bbox. */ if ( have_bbox ) { FT_ERROR(( "Empty glyph has a bbox.\n" )); goto Fail; } } loca_values[i] = dest_offset - glyf_start; if ( WRITE_SFNT_BUF( glyph_buf, glyph_size ) ) goto Fail; if ( pad4( &sfnt, sfnt_size, &dest_offset, memory ) ) goto Fail; *glyf_checksum += compute_ULong_sum( glyph_buf, glyph_size ); /* Store x_mins, may be required to reconstruct `hmtx'. */ if ( n_contours > 0 ) info->x_mins[i] = x_min; } info->glyf_table->dst_length = dest_offset - info->glyf_table->dst_offset; info->loca_table->dst_offset = dest_offset; /* `loca[n]' will be equal to the length of the `glyf' table. */ loca_values[num_glyphs] = info->glyf_table->dst_length; if ( store_loca( loca_values, num_glyphs + 1, index_format, loca_checksum, &sfnt, sfnt_size, &dest_offset, memory ) ) goto Fail; info->loca_table->dst_length = dest_offset - info->loca_table->dst_offset; FT_TRACE4(( " loca table info:\n" )); FT_TRACE4(( " dst_offset = %lu\n", info->loca_table->dst_offset )); FT_TRACE4(( " dst_length = %lu\n", info->loca_table->dst_length )); FT_TRACE4(( " checksum = %09x\n", *loca_checksum )); /* Set pointer `sfnt_bytes' to its correct value. */ *sfnt_bytes = sfnt; *out_offset = dest_offset; FT_FREE( substreams ); FT_FREE( loca_values ); FT_FREE( n_points_arr ); FT_FREE( glyph_buf ); FT_FREE( points ); return error; Fail: if ( !error ) error = FT_THROW( Invalid_Table ); /* Set pointer `sfnt_bytes' to its correct value. */ *sfnt_bytes = sfnt; FT_FREE( substreams ); FT_FREE( loca_values ); FT_FREE( n_points_arr ); FT_FREE( glyph_buf ); FT_FREE( points ); return error; } /* Get `x_mins' for untransformed `glyf' table. */ static FT_Error get_x_mins( FT_Stream stream, WOFF2_Table* tables, FT_UShort num_tables, WOFF2_Info info, FT_Memory memory ) { FT_UShort num_glyphs; FT_UShort index_format; FT_ULong glyf_offset; FT_UShort glyf_offset_short; FT_ULong loca_offset; FT_Int i; FT_Error error = FT_Err_Ok; FT_ULong offset_size; /* At this point of time those tables might not have been read yet. */ const WOFF2_Table maxp_table = find_table( tables, num_tables, TTAG_maxp ); const WOFF2_Table head_table = find_table( tables, num_tables, TTAG_head ); if ( !maxp_table ) { FT_ERROR(( "`maxp' table is missing.\n" )); return FT_THROW( Invalid_Table ); } if ( !head_table ) { FT_ERROR(( "`head' table is missing.\n" )); return FT_THROW( Invalid_Table ); } if ( !info->loca_table ) { FT_ERROR(( "`loca' table is missing.\n" )); return FT_THROW( Invalid_Table ); } /* Read `numGlyphs' field from `maxp' table. */ if ( FT_STREAM_SEEK( maxp_table->src_offset ) || FT_STREAM_SKIP( 8 ) ) return error; if ( FT_READ_USHORT( num_glyphs ) ) return error; info->num_glyphs = num_glyphs; /* Read `indexToLocFormat' field from `head' table. */ if ( FT_STREAM_SEEK( head_table->src_offset ) || FT_STREAM_SKIP( 50 ) ) return error; if ( FT_READ_USHORT( index_format ) ) return error; offset_size = index_format ? 4 : 2; /* Create `x_mins' array. */ if ( FT_NEW_ARRAY( info->x_mins, num_glyphs ) ) return error; loca_offset = info->loca_table->src_offset; for ( i = 0; i < num_glyphs; ++i ) { if ( FT_STREAM_SEEK( loca_offset ) ) return error; loca_offset += offset_size; if ( index_format ) { if ( FT_READ_ULONG( glyf_offset ) ) return error; } else { if ( FT_READ_USHORT( glyf_offset_short ) ) return error; glyf_offset = (FT_ULong)( glyf_offset_short ); glyf_offset = glyf_offset << 1; } glyf_offset += info->glyf_table->src_offset; if ( FT_STREAM_SEEK( glyf_offset ) || FT_STREAM_SKIP( 2 ) ) return error; if ( FT_READ_USHORT( info->x_mins[i] ) ) return error; } return error; } static FT_Error reconstruct_hmtx( FT_Stream stream, FT_UShort num_glyphs, FT_UShort num_hmetrics, FT_Short* x_mins, FT_ULong* checksum, FT_Byte** sfnt_bytes, FT_ULong* sfnt_size, FT_ULong* out_offset, FT_Memory memory ) { FT_Error error = FT_Err_Ok; FT_Byte* sfnt = *sfnt_bytes; FT_ULong dest_offset = *out_offset; FT_Byte hmtx_flags; FT_Bool has_proportional_lsbs, has_monospace_lsbs; FT_ULong hmtx_table_size; FT_Int i; FT_UShort* advance_widths = NULL; FT_Short* lsbs = NULL; FT_Byte* hmtx_table = NULL; FT_Byte* dst = NULL; if ( FT_READ_BYTE( hmtx_flags ) ) goto Fail; has_proportional_lsbs = ( hmtx_flags & 1 ) == 0; has_monospace_lsbs = ( hmtx_flags & 2 ) == 0; /* Bits 2-7 are reserved and MUST be zero. */ if ( ( hmtx_flags & 0xFC ) != 0 ) goto Fail; /* Are you REALLY transformed? */ if ( has_proportional_lsbs && has_monospace_lsbs ) goto Fail; /* Cannot have a transformed `hmtx' without `glyf'. */ if ( ( num_hmetrics > num_glyphs ) || ( num_hmetrics < 1 ) ) goto Fail; /* Must have at least one entry. */ if ( num_hmetrics < 1 ) goto Fail; if ( FT_NEW_ARRAY( advance_widths, num_hmetrics ) || FT_NEW_ARRAY( lsbs, num_glyphs ) ) goto Fail; /* Read `advanceWidth' stream. Always present. */ for ( i = 0; i < num_hmetrics; i++ ) { FT_UShort advance_width; if ( FT_READ_USHORT( advance_width ) ) goto Fail; advance_widths[i] = advance_width; } /* lsb values for proportional glyphs. */ for ( i = 0; i < num_hmetrics; i++ ) { FT_Short lsb; if ( has_proportional_lsbs ) { if ( FT_READ_SHORT( lsb ) ) goto Fail; } else lsb = x_mins[i]; lsbs[i] = lsb; } /* lsb values for monospaced glyphs. */ for ( i = num_hmetrics; i < num_glyphs; i++ ) { FT_Short lsb; if ( has_monospace_lsbs ) { if ( FT_READ_SHORT( lsb ) ) goto Fail; } else lsb = x_mins[i]; lsbs[i] = lsb; } /* Build the hmtx table. */ hmtx_table_size = 2 * num_hmetrics + 2 * num_glyphs; if ( FT_NEW_ARRAY( hmtx_table, hmtx_table_size ) ) goto Fail; dst = hmtx_table; FT_TRACE6(( "hmtx values: \n" )); for ( i = 0; i < num_glyphs; i++ ) { if ( i < num_hmetrics ) { WRITE_SHORT( dst, advance_widths[i] ); FT_TRACE6(( "%d ", advance_widths[i] )); } WRITE_SHORT( dst, lsbs[i] ); FT_TRACE6(( "%d ", lsbs[i] )); } FT_TRACE6(( "\n" )); *checksum = compute_ULong_sum( hmtx_table, hmtx_table_size ); /* Write `hmtx' table to sfnt buffer. */ if ( WRITE_SFNT_BUF( hmtx_table, hmtx_table_size ) ) goto Fail; /* Set pointer `sfnt_bytes' to its correct value. */ *sfnt_bytes = sfnt; *out_offset = dest_offset; FT_FREE( advance_widths ); FT_FREE( lsbs ); FT_FREE( hmtx_table ); return error; Fail: FT_FREE( advance_widths ); FT_FREE( lsbs ); FT_FREE( hmtx_table ); if ( !error ) error = FT_THROW( Invalid_Table ); return error; } static FT_Error reconstruct_font( FT_Byte* transformed_buf, FT_ULong transformed_buf_size, WOFF2_Table* indices, WOFF2_Header woff2, WOFF2_Info info, FT_Byte** sfnt_bytes, FT_ULong* sfnt_size, FT_Memory memory ) { /* Memory management of `transformed_buf' is handled by the caller. */ FT_Error error = FT_Err_Ok; FT_Stream stream = NULL; FT_Byte* buf_cursor = NULL; FT_Byte* table_entry = NULL; /* We are reallocating memory for `sfnt', so its pointer may change. */ FT_Byte* sfnt = *sfnt_bytes; FT_UShort num_tables = woff2->num_tables; FT_ULong dest_offset = 12 + num_tables * 16UL; FT_ULong checksum = 0; FT_ULong loca_checksum = 0; FT_Int nn = 0; FT_UShort num_hmetrics = 0; FT_ULong font_checksum = info->header_checksum; FT_Bool is_glyf_xform = FALSE; FT_ULong table_entry_offset = 12; /* A few table checks before reconstruction. */ /* `glyf' must be present with `loca'. */ info->glyf_table = find_table( indices, num_tables, TTAG_glyf ); info->loca_table = find_table( indices, num_tables, TTAG_loca ); if ( ( info->glyf_table == NULL ) ^ ( info->loca_table == NULL ) ) { FT_ERROR(( "One of `glyf'/`loca' tables missing.\n" )); return FT_THROW( Invalid_Table ); } /* Both `glyf' and `loca' must have same transformation. */ if ( info->glyf_table != NULL ) { if ( ( info->glyf_table->flags & WOFF2_FLAGS_TRANSFORM ) != ( info->loca_table->flags & WOFF2_FLAGS_TRANSFORM ) ) { FT_ERROR(( "Transformation mismatch" " between `glyf' and `loca' table." )); return FT_THROW( Invalid_Table ); } } /* Create buffer for table entries. */ if ( FT_NEW_ARRAY( table_entry, 16 ) ) goto Fail; /* Create a stream for the uncompressed buffer. */ if ( FT_NEW( stream ) ) goto Fail; FT_Stream_OpenMemory( stream, transformed_buf, transformed_buf_size ); FT_ASSERT( FT_STREAM_POS() == 0 ); /* Reconstruct/copy tables to output stream. */ for ( nn = 0; nn < num_tables; nn++ ) { WOFF2_TableRec table = *( indices[nn] ); FT_TRACE3(( "Seeking to %d with table size %d.\n", table.src_offset, table.src_length )); FT_TRACE3(( "Table tag: %c%c%c%c.\n", (FT_Char)( table.Tag >> 24 ), (FT_Char)( table.Tag >> 16 ), (FT_Char)( table.Tag >> 8 ), (FT_Char)( table.Tag ) )); if ( FT_STREAM_SEEK( table.src_offset ) ) goto Fail; if ( table.src_offset + table.src_length > transformed_buf_size ) goto Fail; /* Get stream size for fields of `hmtx' table. */ if ( table.Tag == TTAG_hhea ) { if ( read_num_hmetrics( stream, &num_hmetrics ) ) goto Fail; } info->num_hmetrics = num_hmetrics; checksum = 0; if ( ( table.flags & WOFF2_FLAGS_TRANSFORM ) != WOFF2_FLAGS_TRANSFORM ) { /* Check whether `head' is at least 12 bytes. */ if ( table.Tag == TTAG_head ) { if ( table.src_length < 12 ) goto Fail; buf_cursor = transformed_buf + table.src_offset + 8; /* Set checkSumAdjustment = 0 */ WRITE_ULONG( buf_cursor, 0 ); } table.dst_offset = dest_offset; checksum = compute_ULong_sum( transformed_buf + table.src_offset, table.src_length ); FT_TRACE4(( "Checksum = %09x.\n", checksum )); if ( WRITE_SFNT_BUF( transformed_buf + table.src_offset, table.src_length ) ) goto Fail; } else { FT_TRACE3(( "This table is transformed.\n" )); if ( table.Tag == TTAG_glyf ) { is_glyf_xform = TRUE; table.dst_offset = dest_offset; if ( reconstruct_glyf( stream, &checksum, &loca_checksum, &sfnt, sfnt_size, &dest_offset, info, memory ) ) goto Fail; FT_TRACE4(( "Checksum = %09x.\n", checksum )); } else if ( table.Tag == TTAG_loca ) checksum = loca_checksum; else if ( table.Tag == TTAG_hmtx ) { /* If glyf is not transformed and hmtx is, handle separately. */ if ( !is_glyf_xform ) { if ( get_x_mins( stream, indices, num_tables, info, memory ) ) goto Fail; } table.dst_offset = dest_offset; if ( reconstruct_hmtx( stream, info->num_glyphs, info->num_hmetrics, info->x_mins, &checksum, &sfnt, sfnt_size, &dest_offset, memory ) ) goto Fail; } else { /* Unknown transform. */ FT_ERROR(( "Unknown table transform.\n" )); goto Fail; } } font_checksum += checksum; buf_cursor = &table_entry[0]; WRITE_ULONG( buf_cursor, table.Tag ); WRITE_ULONG( buf_cursor, checksum ); WRITE_ULONG( buf_cursor, table.dst_offset ); WRITE_ULONG( buf_cursor, table.dst_length ); WRITE_SFNT_BUF_AT( table_entry_offset, table_entry, 16 ); /* Update checksum. */ font_checksum += compute_ULong_sum( table_entry, 16 ); if ( pad4( &sfnt, sfnt_size, &dest_offset, memory ) ) goto Fail; /* Sanity check. */ if ( (FT_ULong)( table.dst_offset + table.dst_length ) > dest_offset ) { FT_ERROR(( "Table was partially written.\n" )); goto Fail; } } /* Update `head' checkSumAdjustment. */ info->head_table = find_table( indices, num_tables, TTAG_head ); if ( !info->head_table ) { FT_ERROR(( "`head' table is missing.\n" )); goto Fail; } if ( info->head_table->dst_length < 12 ) goto Fail; buf_cursor = sfnt + info->head_table->dst_offset + 8; font_checksum = 0xB1B0AFBA - font_checksum; WRITE_ULONG( buf_cursor, font_checksum ); FT_TRACE2(( "Final checksum = %09x.\n", font_checksum )); woff2->actual_sfnt_size = dest_offset; /* Set pointer of sfnt stream to its correct value. */ *sfnt_bytes = sfnt; FT_FREE( table_entry ); FT_Stream_Close( stream ); FT_FREE( stream ); return error; Fail: if ( !error ) error = FT_THROW( Invalid_Table ); /* Set pointer of sfnt stream to its correct value. */ *sfnt_bytes = sfnt; FT_FREE( table_entry ); FT_Stream_Close( stream ); FT_FREE( stream ); return error; } /* Replace `face->root.stream' with a stream containing the extracted */ /* SFNT of a WOFF2 font. */ FT_LOCAL_DEF( FT_Error ) woff2_open_font( FT_Stream stream, TT_Face face, FT_Int* face_instance_index, FT_Long* num_faces ) { FT_Memory memory = stream->memory; FT_Error error = FT_Err_Ok; FT_Int face_index; WOFF2_HeaderRec woff2; WOFF2_InfoRec info = { 0, 0, 0, NULL, NULL, NULL, NULL }; WOFF2_Table tables = NULL; WOFF2_Table* indices = NULL; WOFF2_Table* temp_indices = NULL; WOFF2_Table last_table; FT_Int nn; FT_ULong j; FT_ULong flags; FT_UShort xform_version; FT_ULong src_offset = 0; FT_UInt glyf_index; FT_UInt loca_index; FT_UInt32 file_offset; FT_Byte* sfnt = NULL; FT_Stream sfnt_stream = NULL; FT_Byte* sfnt_header; FT_ULong sfnt_size; FT_Byte* uncompressed_buf = NULL; static const FT_Frame_Field woff2_header_fields[] = { #undef FT_STRUCTURE #define FT_STRUCTURE WOFF2_HeaderRec FT_FRAME_START( 48 ), FT_FRAME_ULONG ( signature ), FT_FRAME_ULONG ( flavor ), FT_FRAME_ULONG ( length ), FT_FRAME_USHORT ( num_tables ), FT_FRAME_SKIP_BYTES( 2 ), FT_FRAME_ULONG ( totalSfntSize ), FT_FRAME_ULONG ( totalCompressedSize ), FT_FRAME_SKIP_BYTES( 2 * 2 ), FT_FRAME_ULONG ( metaOffset ), FT_FRAME_ULONG ( metaLength ), FT_FRAME_ULONG ( metaOrigLength ), FT_FRAME_ULONG ( privOffset ), FT_FRAME_ULONG ( privLength ), FT_FRAME_END }; FT_ASSERT( stream == face->root.stream ); FT_ASSERT( FT_STREAM_POS() == 0 ); face_index = FT_ABS( *face_instance_index ) & 0xFFFF; /* Read WOFF2 Header. */ if ( FT_STREAM_READ_FIELDS( woff2_header_fields, &woff2 ) ) return error; FT_TRACE4(( "signature -> 0x%X\n", woff2.signature )); FT_TRACE2(( "flavor -> 0x%08lx\n", woff2.flavor )); FT_TRACE4(( "length -> %lu\n", woff2.length )); FT_TRACE2(( "num_tables -> %hu\n", woff2.num_tables )); FT_TRACE4(( "totalSfntSize -> %lu\n", woff2.totalSfntSize )); FT_TRACE4(( "metaOffset -> %hu\n", woff2.metaOffset )); FT_TRACE4(( "metaLength -> %hu\n", woff2.metaLength )); FT_TRACE4(( "privOffset -> %hu\n", woff2.privOffset )); FT_TRACE4(( "privLength -> %hu\n", woff2.privLength )); /* Make sure we don't recurse back here. */ if ( woff2.flavor == TTAG_wOF2 ) return FT_THROW( Invalid_Table ); /* Miscellaneous checks. */ if ( woff2.length != stream->size || woff2.num_tables == 0 || 48 + woff2.num_tables * 20UL >= woff2.length || ( woff2.metaOffset == 0 && ( woff2.metaLength != 0 || woff2.metaOrigLength != 0 ) ) || ( woff2.metaLength != 0 && woff2.metaOrigLength == 0 ) || ( woff2.metaOffset >= woff2.length ) || ( woff2.length - woff2.metaOffset < woff2.metaLength ) || ( woff2.privOffset == 0 && woff2.privLength != 0 ) || ( woff2.privOffset >= woff2.length ) || ( woff2.length - woff2.privOffset < woff2.privLength ) ) { FT_ERROR(( "woff2_open_font: invalid WOFF2 header\n" )); return FT_THROW( Invalid_Table ); } FT_TRACE2(( "woff2_open_font: WOFF2 Header is valid.\n" )); woff2.ttc_fonts = NULL; /* Read table directory. */ if ( FT_NEW_ARRAY( tables, woff2.num_tables ) || FT_NEW_ARRAY( indices, woff2.num_tables ) ) goto Exit; FT_TRACE2(( "\n" " tag flags transform origLen transformLen\n" " --------------------------------------------------\n" )); for ( nn = 0; nn < woff2.num_tables; nn++ ) { WOFF2_Table table = tables + nn; if ( FT_READ_BYTE( table->FlagByte ) ) goto Exit; if ( ( table->FlagByte & 0x3f ) == 0x3f ) { if ( FT_READ_ULONG( table->Tag ) ) goto Exit; } else { table->Tag = woff2_known_tags( table->FlagByte & 0x3f ); if ( !table->Tag ) { FT_ERROR(( "woff2_open_font: Unknown table tag." )); error = FT_THROW( Invalid_Table ); goto Exit; } } flags = 0; xform_version = ( table->FlagByte >> 6 ) & 0x03; /* 0 means xform for glyph/loca, non-0 for others. */ if ( table->Tag == TTAG_glyf || table->Tag == TTAG_loca ) { if ( xform_version == 0 ) flags |= WOFF2_FLAGS_TRANSFORM; } else if ( xform_version != 0 ) flags |= WOFF2_FLAGS_TRANSFORM; flags |= xform_version; if ( READ_BASE128( table->dst_length ) ) goto Exit; table->TransformLength = table->dst_length; if ( ( flags & WOFF2_FLAGS_TRANSFORM ) != 0 ) { if ( READ_BASE128( table->TransformLength ) ) goto Exit; if ( table->Tag == TTAG_loca && table->TransformLength ) { FT_ERROR(( "woff2_open_font: Invalid loca `transformLength'.\n" )); error = FT_THROW( Invalid_Table ); goto Exit; } } if ( src_offset + table->TransformLength < src_offset ) { FT_ERROR(( "woff2_open_font: invalid WOFF2 table directory.\n" )); error = FT_THROW( Invalid_Table ); goto Exit; } table->src_offset = src_offset; table->src_length = table->TransformLength; src_offset += table->TransformLength; table->flags = flags; FT_TRACE2(( " %c%c%c%c %08d %08d %08ld %08ld\n", (FT_Char)( table->Tag >> 24 ), (FT_Char)( table->Tag >> 16 ), (FT_Char)( table->Tag >> 8 ), (FT_Char)( table->Tag ), table->FlagByte & 0x3f, ( table->FlagByte >> 6 ) & 0x03, table->dst_length, table->TransformLength, table->src_length, table->src_offset )); indices[nn] = table; } /* End of last table is uncompressed size. */ last_table = indices[woff2.num_tables - 1]; woff2.uncompressed_size = last_table->src_offset + last_table->src_length; if ( woff2.uncompressed_size < last_table->src_offset ) { error = FT_THROW( Invalid_Table ); goto Exit; } FT_TRACE2(( "Table directory parsed.\n" )); /* Check for and read collection directory. */ woff2.num_fonts = 1; woff2.header_version = 0; if ( woff2.flavor == TTAG_ttcf ) { FT_TRACE2(( "Font is a TTC, reading collection directory.\n" )); if ( FT_READ_ULONG( woff2.header_version ) ) goto Exit; if ( woff2.header_version != 0x00010000 && woff2.header_version != 0x00020000 ) { error = FT_THROW( Invalid_Table ); goto Exit; } if ( READ_255USHORT( woff2.num_fonts ) ) goto Exit; if ( !woff2.num_fonts ) { error = FT_THROW( Invalid_Table ); goto Exit; } FT_TRACE4(( "Number of fonts in TTC: %ld\n", woff2.num_fonts )); if ( FT_NEW_ARRAY( woff2.ttc_fonts, woff2.num_fonts ) ) goto Exit; for ( nn = 0; nn < woff2.num_fonts; nn++ ) { WOFF2_TtcFont ttc_font = woff2.ttc_fonts + nn; if ( READ_255USHORT( ttc_font->num_tables ) ) goto Exit; if ( FT_READ_ULONG( ttc_font->flavor ) ) goto Exit; if ( FT_NEW_ARRAY( ttc_font->table_indices, ttc_font->num_tables ) ) goto Exit; FT_TRACE5(( "Number of tables in font %d: %ld\n", nn, ttc_font->num_tables )); #ifdef FT_DEBUG_LEVEL_TRACE if ( ttc_font->num_tables ) FT_TRACE6(( " Indices: " )); #endif glyf_index = 0; loca_index = 0; for ( j = 0; j < ttc_font->num_tables; j++ ) { FT_UShort table_index; WOFF2_Table table; if ( READ_255USHORT( table_index ) ) goto Exit; FT_TRACE6(( "%hu ", table_index )); if ( table_index >= woff2.num_tables ) { FT_ERROR(( "woff2_open_font: invalid table index\n" )); error = FT_THROW( Invalid_Table ); goto Exit; } ttc_font->table_indices[j] = table_index; table = indices[table_index]; if ( table->Tag == TTAG_loca ) loca_index = table_index; if ( table->Tag == TTAG_glyf ) glyf_index = table_index; } #ifdef FT_DEBUG_LEVEL_TRACE if ( ttc_font->num_tables ) FT_TRACE6(( "\n" )); #endif /* glyf and loca must be consecutive */ if ( glyf_index > 0 || loca_index > 0 ) { if ( glyf_index > loca_index || loca_index - glyf_index != 1 ) { error = FT_THROW( Invalid_Table ); goto Exit; } } } /* Collection directory reading complete. */ FT_TRACE2(( "WOFF2 collection directory is valid.\n" )); } else woff2.ttc_fonts = NULL; woff2.compressed_offset = FT_STREAM_POS(); file_offset = ROUND4( woff2.compressed_offset + woff2.totalCompressedSize ); /* Some more checks before we start reading the tables. */ if ( file_offset > woff2.length ) { error = FT_THROW( Invalid_Table ); goto Exit; } if ( woff2.metaOffset ) { if ( file_offset != woff2.metaOffset ) { error = FT_THROW( Invalid_Table ); goto Exit; } file_offset = ROUND4(woff2.metaOffset + woff2.metaLength); } if ( woff2.privOffset ) { if ( file_offset != woff2.privOffset ) { error = FT_THROW( Invalid_Table ); goto Exit; } file_offset = ROUND4(woff2.privOffset + woff2.privLength); } if ( file_offset != ( ROUND4( woff2.length ) ) ) { error = FT_THROW( Invalid_Table ); goto Exit; } /* Validate requested face index. */ *num_faces = woff2.num_fonts; /* value -(N+1) requests information on index N */ if ( *face_instance_index < 0 ) face_index--; if ( face_index >= woff2.num_fonts ) { if ( *face_instance_index >= 0 ) { error = FT_THROW( Invalid_Argument ); goto Exit; } else face_index = 0; } /* Only retain tables of the requested face in a TTC. */ if ( woff2.header_version ) { WOFF2_TtcFont ttc_font = woff2.ttc_fonts + face_index; /* Create a temporary array. */ if ( FT_NEW_ARRAY( temp_indices, ttc_font->num_tables ) ) goto Exit; FT_TRACE4(( "Storing tables for TTC face index %d.\n", face_index )); for ( nn = 0; nn < ttc_font->num_tables; nn++ ) temp_indices[nn] = indices[ttc_font->table_indices[nn]]; /* Resize array to required size. */ if ( FT_RENEW_ARRAY( indices, woff2.num_tables, ttc_font->num_tables ) ) goto Exit; for ( nn = 0; nn < ttc_font->num_tables; nn++ ) indices[nn] = temp_indices[nn]; FT_FREE( temp_indices ); /* Change header values. */ woff2.flavor = ttc_font->flavor; woff2.num_tables = ttc_font->num_tables; } /* We need to allocate this much at the minimum. */ sfnt_size = 12 + woff2.num_tables * 16UL; /* This is what we normally expect. */ /* Initially trust `totalSfntSize' and change later as required. */ if ( woff2.totalSfntSize > sfnt_size ) { /* However, adjust the value to something reasonable. */ /* Factor 64 is heuristic. */ if ( ( woff2.totalSfntSize >> 6 ) > woff2.length ) sfnt_size = woff2.length << 6; else sfnt_size = woff2.totalSfntSize; /* Value 1<<26 = 67108864 is heuristic. */ if (sfnt_size >= (1 << 26)) sfnt_size = 1 << 26; #ifdef FT_DEBUG_LEVEL_TRACE if ( sfnt_size != woff2.totalSfntSize ) FT_TRACE4(( "adjusting estimate of uncompressed font size" " to %lu bytes\n", sfnt_size )); #endif } /* Write sfnt header. */ if ( FT_ALLOC( sfnt, sfnt_size ) || FT_NEW( sfnt_stream ) ) goto Exit; sfnt_header = sfnt; WRITE_ULONG( sfnt_header, woff2.flavor ); if ( woff2.num_tables ) { FT_UInt searchRange, entrySelector, rangeShift, x; x = woff2.num_tables; entrySelector = 0; while ( x ) { x >>= 1; entrySelector += 1; } entrySelector--; searchRange = ( 1 << entrySelector ) * 16; rangeShift = ( woff2.num_tables * 16 ) - searchRange; WRITE_USHORT( sfnt_header, woff2.num_tables ); WRITE_USHORT( sfnt_header, searchRange ); WRITE_USHORT( sfnt_header, entrySelector ); WRITE_USHORT( sfnt_header, rangeShift ); } info.header_checksum = compute_ULong_sum( sfnt, 12 ); /* Sort tables by tag. */ ft_qsort( indices, woff2.num_tables, sizeof ( WOFF2_Table ), compare_tags ); if ( woff2.uncompressed_size < 1 ) { error = FT_THROW( Invalid_Table ); goto Exit; } if ( woff2.uncompressed_size > sfnt_size ) { FT_ERROR(( "woff2_open_font: SFNT table lengths are too large.\n" )); error = FT_THROW( Invalid_Table ); goto Exit; } /* Allocate memory for uncompressed table data. */ if ( FT_ALLOC( uncompressed_buf, woff2.uncompressed_size ) || FT_FRAME_ENTER( woff2.totalCompressedSize ) ) goto Exit; /* Uncompress the stream. */ error = woff2_decompress( uncompressed_buf, woff2.uncompressed_size, stream->cursor, woff2.totalCompressedSize ); FT_FRAME_EXIT(); if ( error ) goto Exit; error = reconstruct_font( uncompressed_buf, woff2.uncompressed_size, indices, &woff2, &info, &sfnt, &sfnt_size, memory ); if ( error ) goto Exit; /* Resize `sfnt' to actual size of sfnt stream. */ if ( woff2.actual_sfnt_size < sfnt_size ) { FT_TRACE5(( "Trimming sfnt stream from %lu to %lu.\n", sfnt_size, woff2.actual_sfnt_size )); if ( FT_REALLOC( sfnt, (FT_ULong)( sfnt_size ), (FT_ULong)( woff2.actual_sfnt_size ) ) ) goto Exit; } /* `reconstruct_font' has done all the work. */ /* Swap out stream and return. */ FT_Stream_OpenMemory( sfnt_stream, sfnt, woff2.actual_sfnt_size ); sfnt_stream->memory = stream->memory; sfnt_stream->close = stream_close; FT_Stream_Free( face->root.stream, ( face->root.face_flags & FT_FACE_FLAG_EXTERNAL_STREAM ) != 0 ); face->root.stream = sfnt_stream; face->root.face_flags &= ~FT_FACE_FLAG_EXTERNAL_STREAM; /* Set face_index to 0 or -1. */ if ( *face_instance_index >= 0 ) *face_instance_index = 0; else *face_instance_index = -1; FT_TRACE2(( "woff2_open_font: SFNT synthesized.\n" )); Exit: FT_FREE( tables ); FT_FREE( indices ); FT_FREE( uncompressed_buf ); FT_FREE( info.x_mins ); if ( woff2.ttc_fonts ) { WOFF2_TtcFont ttc_font = woff2.ttc_fonts; for ( nn = 0; nn < woff2.num_fonts; nn++ ) { FT_FREE( ttc_font->table_indices ); ttc_font++; } FT_FREE( woff2.ttc_fonts ); } if ( error ) { FT_FREE( sfnt ); if ( sfnt_stream ) { FT_Stream_Close( sfnt_stream ); FT_FREE( sfnt_stream ); } } return error; } #undef READ_255USHORT #undef READ_BASE128 #undef ROUND4 #undef WRITE_USHORT #undef WRITE_ULONG #undef WRITE_SHORT #undef WRITE_SFNT_BUF #undef WRITE_SFNT_BUF_AT #undef N_CONTOUR_STREAM #undef N_POINTS_STREAM #undef FLAG_STREAM #undef GLYPH_STREAM #undef COMPOSITE_STREAM #undef BBOX_STREAM #undef INSTRUCTION_STREAM /* END */