public override Stream OpenEntry(ArcFile arc, Entry entry)
{
var nsa_arc = arc as NsaEncryptedArchive;
if (null == nsa_arc)
{
var input = arc.File.CreateStream(entry.Offset, entry.Size);
return(UnpackEntry(input, entry as NsaEntry));
}
var encrypted = new EncryptedViewStream(arc.File, nsa_arc.Key);
var stream = new StreamRegion(encrypted, entry.Offset, entry.Size);
return(UnpackEntry(stream, entry as NsaEntry));
}
public override ArcFile TryOpen(ArcView file)
{
List <Entry> dir = null;
bool zero_signature = 0 == file.View.ReadInt16(0);
try
{
using (var input = file.CreateStream())
{
if (zero_signature)
{
input.Seek(2, SeekOrigin.Begin);
}
dir = ReadIndex(input);
if (null != dir)
{
return(new ArcFile(file, this, dir));
}
}
}
catch { /* ignore parse errors */ }
if (zero_signature || !file.Name.HasExtension(".nsa"))
{
return(null);
}
var password = QueryPassword();
if (string.IsNullOrEmpty(password))
{
return(null);
}
var key = Encoding.ASCII.GetBytes(password);
using (var input = new EncryptedViewStream(file, key))
{
dir = ReadIndex(input);
if (null == dir)
{
return(null);
}
return(new NsaEncryptedArchive(file, this, dir, key));
}
}
public override ArcFile TryOpen(ArcView file)
{
List<Entry> dir = null;
bool zero_signature = 0 == file.View.ReadInt16 (0);
try
{
using (var input = file.CreateStream())
{
if (zero_signature)
input.Seek (2, SeekOrigin.Begin);
dir = ReadIndex (input);
if (null != dir)
return new ArcFile (file, this, dir);
}
}
catch { /* ignore parse errors */ }
if (zero_signature || !file.Name.EndsWith (".nsa", StringComparison.InvariantCultureIgnoreCase))
return null;
var password = QueryPassword();
if (string.IsNullOrEmpty (password))
return null;
var key = Encoding.ASCII.GetBytes (password);
using (var input = new EncryptedViewStream (file, key))
{
dir = ReadIndex (input);
if (null == dir)
return null;
return new NsaEncryptedArchive (file, this, dir, key);
}
}
public override Stream OpenEntry(ArcFile arc, Entry entry)
{
var nsa_arc = arc as NsaEncryptedArchive;
if (null == nsa_arc)
{
var input = arc.File.CreateStream (entry.Offset, entry.Size);
return UnpackEntry (input, entry as NsaEntry);
}
var encrypted = new EncryptedViewStream (arc.File, nsa_arc.Key);
var stream = new StreamRegion (encrypted, entry.Offset, entry.Size);
return UnpackEntry (stream, entry as NsaEntry);
}