public static IEnumerable <PotentialArray> FindArrays(
byte[] payload)
{
using (var reader = new TeraBinaryReader(payload))
{
for (var i = 0; i < reader.Length; i++)
{
reader.Position = i;
if (!reader.CanRead(sizeof(ushort) * 2))
{
break;
}
var countPos = reader.Position;
var count = reader.ReadUInt16();
var offsetPos = reader.Position;
var offset = reader.ReadUInt16() -
PacketHeader.HeaderSize;
if (count == 0 ||
(count * (sizeof(ushort) * 2 + sizeof(byte)) +
sizeof(ushort) * 2) > reader.Length)
{
continue;
}
var positions = new HashSet <int>
{
countPos,
countPos + sizeof(byte),
offsetPos,
offsetPos + sizeof(byte)
};
var elems = new List <PotentialArrayElement>();
var good = true;
var last = offsetPos;
var next = offset;
while (next != -PacketHeader.HeaderSize)
{
if (!(good = next >= 0 && next > last &&
next <= reader.Length - sizeof(ushort) * 2 - sizeof(byte)))
{
break;
}
last = next + sizeof(ushort) * 2;
reader.Position = next;
var herePos = reader.Position;
var here = reader.ReadUInt16() -
PacketHeader.HeaderSize;
if (!(good = here == herePos && here == next &&
positions.Add(herePos) &&
positions.Add(herePos + sizeof(byte))))
{
break;
}
var nextPos = reader.Position;
next = reader.ReadUInt16() -
PacketHeader.HeaderSize;
if (!(good = positions.Add(nextPos) &&
positions.Add(nextPos + sizeof(byte))))
{
break;
}
elems.Add(new PotentialArrayElement((ushort)here,
nextPos, (ushort)(next == -PacketHeader.HeaderSize ?
0 : next)));
}
if (good && elems.Count == count)
{
yield return(new PotentialArray(countPos, count,
offsetPos, (ushort)offset, elems));
}
}
}
}
public static IEnumerable <PotentialString> FindStrings(
byte[] payload, bool whiteSpace, bool control, int minLength)
{
using (var reader = new TeraBinaryReader(payload))
{
for (var i = 0; i < reader.Length; i++)
{
reader.Position = i;
if (!reader.CanRead(sizeof(ushort)))
{
break;
}
var offsetPos = reader.Position;
var offset = reader.ReadUInt16() - PacketHeader.HeaderSize;
if (offset < 0 || offset < offsetPos + sizeof(ushort) ||
offset > reader.Length - sizeof(char))
{
continue;
}
reader.Position = offset;
string str;
try
{
str = reader.ReadString();
if (offset < offsetPos &&
reader.Position > offsetPos)
{
continue;
}
TeraBinaryReader.Encoding.GetString(
TeraBinaryReader.Encoding.GetBytes(str));
}
catch (Exception e) when(IsStringException(e))
{
continue;
}
if (!whiteSpace && string.IsNullOrWhiteSpace(str))
{
continue;
}
if (minLength != 0 && str.Length < minLength)
{
continue;
}
var hasBadChars = str.Any(c =>
{
var cat = char.GetUnicodeCategory(c);
return(cat == UnicodeCategory.Control ||
cat == UnicodeCategory.Format ||
cat == UnicodeCategory.OtherNotAssigned ||
cat == UnicodeCategory.PrivateUse ||
cat == UnicodeCategory.Surrogate);
});
if (!control && hasBadChars)
{
continue;
}
yield return(new PotentialString(offsetPos,
(ushort)offset, str));
}
}
}