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#include "header.h"
#include "read.h"
#include "global_elements.h"
#ifdef WA_VALIDATE
extern uint64_t max_id_length;
extern uint64_t max_size_length;
#endif
// returns bytes read. 0 means EOF
uint64_t nsmkv::ReadHeader(nsmkv::MKVReader *reader, uint64_t size, nsmkv::Header &header)
{
uint64_t total_bytes_read=0;
while (size)
{
ebml_node node;
uint64_t bytes_read = read_ebml_node(reader, &node);
if (bytes_read == 0)
return 0;
// benski> checking bytes_read and node.size separately prevents possible integer overflow attack
if (bytes_read > size)
return 0;
total_bytes_read+=bytes_read;
size-=bytes_read;
if (node.size > size)
return 0;
total_bytes_read+=node.size;
size-=node.size;
switch(node.id)
{
case mkv_header_doctype:
{
char *utf8=0;
if (read_utf8(reader, node.size, &utf8) == 0)
return 0;
header.OwnDocType(utf8);
#ifdef WA_VALIDATE
header.doctype_found = true;
printf(" DocType: %s\n", header.doctype);
#endif
}
break;
case mkv_header_doctype_version:
{
uint64_t val;
if (read_unsigned(reader, node.size, &val) == 0)
return 0;
header.doctype_version = val;
#ifdef WA_VALIDATE
header.doctype_version_found = true;
printf(" DocType Version: %I64u\n", header.doctype_version);
#endif
}
break;
case mkv_header_doctype_read_version:
{
uint64_t val;
if (read_unsigned(reader, node.size, &val) == 0)
return 0;
header.doctype_read_version = val;
#ifdef WA_VALIDATE
header.doctype_read_version_found = true;
printf(" DocType Read Version: %I64u\n", header.doctype_read_version);
#endif
}
break;
case mkv_header_ebml_version:
{
uint64_t val;
if (read_unsigned(reader, node.size, &val) == 0)
return 0;
header.ebml_version = val;
#ifdef WA_VALIDATE
header.ebml_version_found = true;
printf(" EBML Version: %I64u\n", header.ebml_version);
#endif
}
break;
case mkv_header_ebml_read_version:
{
uint64_t val;
if (read_unsigned(reader, node.size, &val) == 0)
return 0;
header.ebml_read_version = val;
#ifdef WA_VALIDATE
header.ebml_read_version_found = true;
printf(" EBML Read Version: %I64u\n", header.ebml_read_version);
#endif
}
break;
case mkv_header_ebml_max_id_length:
{
uint64_t val;
if (read_unsigned(reader, node.size, &val) == 0)
return 0;
header.ebml_max_id_length = val;
#ifdef WA_VALIDATE
max_id_length = val;
header.ebml_max_id_length_found = true;
printf(" EBML Max ID Length: %I64u\n", header.ebml_max_id_length);
#endif
}
break;
case mkv_header_ebml_max_size_length:
{
uint64_t val;
if (read_unsigned(reader, node.size, &val) == 0)
return 0;
header.ebml_max_size_length = val;
#ifdef WA_VALIDATE
max_size_length = val;
header.ebml_max_size_length_found = true;
printf(" EBML Max Size Length: %I64u\n", header.ebml_max_size_length);
#endif
}
break;
default:
{
if (ReadGlobal(reader, node.id, node.size) == 0)
return 0;
}
}
}
return total_bytes_read;
}
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