private static InfoHash ComputeInfoHash(BEncoding.Dictionary info)
{
using (var stream = new MemoryStream())
{
BEncoding.Encode(info, stream);
stream.Seek(0L, SeekOrigin.Begin);
byte[] hash = HashHelper.ComputeSHA1(stream);
return(new InfoHash(hash));
}
}
private ScrapeResponse HandleScrapeResponse(BEncoding.Dictionary info)
{
BEncoding.Dictionary files;
if (!info.TryGetDictionary("files", out files))
{
return(null);
}
var torrentInfos = new List <ScrapeResponse.TorrentInfo>(files.Count);
foreach (var torrentInfo in files)
{
var torrentInfoDict = (torrentInfo.Value as BEncoding.Dictionary);
if (torrentInfoDict == null)
{
continue;
}
long completeCount, incompleteCount, downloadedCount;
string torrentName;
if (!torrentInfoDict.TryGetInteger("complete", out completeCount))
{
completeCount = 0;
}
if (!torrentInfoDict.TryGetInteger("incomplete", out incompleteCount))
{
incompleteCount = 0;
}
if (!torrentInfoDict.TryGetInteger("downloaded", out downloadedCount))
{
downloadedCount = 0;
}
if (!torrentInfoDict.TryGetString("name", out torrentName))
{
torrentName = null;
}
byte[] infoHashBytes = Encoding.UTF8.GetBytes(torrentInfo.Key); // TODO: Is this okay to do?
var infoHash = new InfoHash(infoHashBytes);
torrentInfos.Add(new ScrapeResponse.TorrentInfo(infoHash, (int)completeCount, (int)incompleteCount, (int)downloadedCount, torrentName));
}
return(new ScrapeResponse(this, torrentInfos.ToArray()));
}
private AnnounceResponse HandleAnnounceResponse(BEncoding.Dictionary info)
{
string failureReason, warningMessage;
if (info.TryGetString("failure reason", out failureReason))
{
this.failureMessage = failureReason;
}
if (info.TryGetString("warning message", out warningMessage))
{
this.warningMessage = warningMessage;
}
long completeCount, incompleteCount, downloadedCount, interval, minInterval;
if (info.TryGetInteger("complete", out completeCount))
{
this.completeCount = (int)completeCount;
}
if (info.TryGetInteger("incomplete", out incompleteCount))
{
this.incompleteCount = (int)incompleteCount;
}
if (info.TryGetInteger("downloaded", out downloadedCount))
{
this.downloadedCount = (int)downloadedCount;
}
if (info.TryGetInteger("interval", out interval))
{
this.interval = TimeSpan.FromSeconds(interval);
}
if (info.TryGetInteger("min interval", out minInterval))
{
this.minInterval = TimeSpan.FromSeconds(minInterval);
if (this.interval < this.minInterval)
{
this.interval = this.minInterval;
}
}
string trackerID;
if (info.TryGetString("tracker id", out trackerID))
{
this.trackerID = trackerID;
}
PeerInfo[] peerInfos = null;
byte[] compactPeerBytes;
BEncoding.List peerList;
if (info.TryGetByteArray("peers", out compactPeerBytes))
{
peerInfos = DecodePeers(compactPeerBytes);
}
else if (info.TryGetList("peers", out peerList))
{
peerInfos = DecodePeers(peerList);
}
// Decode IPv6 peers
if (info.TryGetByteArray("peers6", out compactPeerBytes))
{
var peerInfosV6 = DecodePeers(compactPeerBytes);
if (peerInfosV6 != null)
{
if (peerInfos != null && peerInfos.Length > 0)
{
peerInfos = peerInfos.Concat(peerInfosV6).ToArray();
}
else
{
peerInfos = peerInfosV6;
}
}
}
return(new AnnounceResponse(this, failureReason, warningMessage, peerInfos));
}
private BEncoding.Dictionary Save()
{
var torrentInfo = new BEncoding.Dictionary();
// Make sure that there is a piece size
if (pieceSize == 0)
{
throw new InvalidOperationException("No piece size has been set yet.");
}
else if (!MathHelper.IsPowerOfTwo(pieceSize))
{
throw new InvalidOperationException("The piece size must be a power of two.");
}
else if (files == null || files.Length == 0)
{
throw new InvalidOperationException("No files have been defined yet.");
}
else if (totalSize == 0L)
{
throw new InvalidOperationException("The total size of the torrent cannot be 0.");
}
int pieceCount = (int)((totalSize - 1) / pieceSize) + 1;
if (pieceCount != pieceHashes.Length)
{
throw new InvalidOperationException(string.Format("The calculated number of pieces is {0} while there are {1} piece hashes.", pieceCount, pieceHashes.Length));
}
if (announces != null && announces.Length > 0)
{
if (!string.IsNullOrEmpty(announces[0].Url))
{
torrentInfo.Add("announce", announces[0].Url);
}
var trackerList = new BEncoding.List();
for (int i = 0; i < announces.Length; i++)
{
var urls = announces[i].Urls;
if (urls == null || urls.Length == 0)
{
continue;
}
var urlList = new BEncoding.List();
for (int j = 0; j < urls.Length; j++)
{
if (!string.IsNullOrEmpty(urls[j]))
{
urlList.Add(urls[j]);
}
}
if (urlList.Count > 0)
{
trackerList.Add(urlList);
}
}
if (trackerList.Count > 0)
{
torrentInfo.Add("announce-list", trackerList);
}
}
if (!string.IsNullOrEmpty(comment))
{
torrentInfo.Add("comment", comment);
}
if (!string.IsNullOrEmpty(createdBy))
{
torrentInfo.Add("created by", createdBy);
}
if (creationDate != DateTime.MinValue)
{
long creationDateTimestamp = TimeHelper.GetUnixTimestampFromDate(creationDate);
torrentInfo.Add("creation date", creationDateTimestamp);
}
// Get the piece hash data
byte[] pieceHashData = new byte[20 * pieceCount];
for (int i = 0; i < pieceCount; i++)
{
Buffer.BlockCopy(pieceHashes[i].Hash, 0, pieceHashData, (i * 20), 20);
}
var info = new BEncoding.Dictionary();
info.Add("piece length", pieceSize);
info.Add("pieces", pieceHashData);
info.Add("private", (isPrivate ? 1 : 0));
if (!string.IsNullOrEmpty(source))
{
info.Add("source", source);
}
if (files != null)
{
if (files.Length == 1)
{
var fileItem = files[0];
info.Add("length", fileItem.Size);
if (fileItem.MD5Hash != null && fileItem.MD5Hash.Length == 16)
{
string fileMD5HashHex = HexHelper.BytesToHex(fileItem.MD5Hash);
info.Add("md5sum", fileMD5HashHex);
}
info.Add("name", GetFileName(fileItem.Path));
}
else if (files.Length > 1)
{
info.Add("name", name ?? "Unnamed");
var fileList = new BEncoding.List();
for (int i = 0; i < files.Length; i++)
{
var fileItem = files[i];
var fileDictionary = new BEncoding.Dictionary();
fileDictionary.Add("length", fileItem.Size);
if (fileItem.MD5Hash != null && fileItem.MD5Hash.Length == 16)
{
string fileMD5HashHex = HexHelper.BytesToHex(fileItem.MD5Hash);
info.Add("md5sum", fileMD5HashHex);
}
string[] pathParts = fileItem.Path.Split(new char[] { '/' });
var pathList = new BEncoding.List(pathParts);
fileDictionary.Add("path", pathList);
fileList.Add(fileDictionary);
}
info.Add("files", fileList);
}
}
infoHash = ComputeInfoHash(info);
torrentInfo.Add("info", info);
return(torrentInfo);
}
private void Load(BEncoding.Dictionary torrentInfo)
{
ClearInfo();
BEncoding.List announceList;
if (torrentInfo.TryGetList("announce-list", out announceList))
{
int announceCount = announceList.Count;
var newAnnounceList = new List <AnnounceItem>(announceCount);
for (int i = 0; i < announceCount; i++)
{
var urlList = (announceList[i] as BEncoding.List);
if (urlList != null)
{
int urlCount = urlList.Count;
var newUrlList = new List <string>(urlCount);
for (int j = 0; j < urlCount; j++)
{
string url = urlList.GetString(j);
if (!string.IsNullOrEmpty(url))
{
newUrlList.Add(url);
}
}
if (newUrlList.Count > 0)
{
newAnnounceList.Add(new AnnounceItem(newUrlList.ToArray()));
}
}
}
announces = newAnnounceList.ToArray();
}
else
{
string announceUrl;
if (torrentInfo.TryGetString("announce", out announceUrl))
{
announces = new AnnounceItem[]
{
new AnnounceItem(announceUrl)
};
}
}
long creationDateTimestamp;
if (!torrentInfo.TryGetString("comment", out comment))
{
comment = null;
}
if (!torrentInfo.TryGetString("created by", out createdBy))
{
createdBy = null;
}
if (torrentInfo.TryGetInteger("creation date", out creationDateTimestamp))
{
creationDate = TimeHelper.GetDateFromUnixTimestamp(creationDateTimestamp);
}
else
{
creationDate = DateTime.MinValue;
}
BEncoding.Dictionary info;
if (!torrentInfo.TryGetDictionary("info", out info))
{
throw new InvalidDataException("The info dictionary is missing in the torrent meta-data.");
}
infoHash = ComputeInfoHash(info);
long pieceSize;
if (!info.TryGetInteger("piece length", out pieceSize))
{
throw new InvalidDataException("The piece length is missing in the torrent meta-data. But it is required for all torrents.");
}
byte[] pieceHashData;
if (!info.TryGetByteArray("pieces", out pieceHashData))
{
throw new InvalidDataException("The piece hashes are missing in the torrent meta-data. But it is required for all torrents.");
}
else if ((pieceHashData.Length % 20) != 0)
{
throw new InvalidDataException("The piece hashes are invalid in the torrent meta-data. It must be a multiple of 20 (for SHA1 hashes).");
}
int pieceCount = (pieceHashData.Length / 20);
pieceHashes = new PieceHash[pieceCount];
for (int i = 0; i < pieceCount; i++)
{
byte[] pieceHashBytes = new byte[20];
Buffer.BlockCopy(pieceHashData, (i * 20), pieceHashBytes, 0, 20);
pieceHashes[i] = new PieceHash(pieceHashBytes);
}
long isPrivate;
if (info.TryGetInteger("private", out isPrivate) && isPrivate == 1)
{
this.isPrivate = true;
}
if (!info.TryGetString("source", out source))
{
source = null;
}
if (!info.TryGetString("name", out name) || string.IsNullOrEmpty(name))
{
throw new InvalidDataException("The name string is missing in the torrent meta-data. But it is required for all torrents.");
}
this.pieceSize = (int)pieceSize;
BEncoding.List fileList;
if (info.TryGetList("files", out fileList))
{
int fileCount = fileList.Count;
files = new FileItem[fileCount];
for (int i = 0; i < fileCount; i++)
{
var fileItem = fileList[i] as BEncoding.Dictionary;
if (fileItem == null)
{
throw new InvalidDataException("The format of the torrent meta-data is invalid. Expected a dictionary of file information.");
}
long fileSize;
if (!fileItem.TryGetInteger("length", out fileSize))
{
throw new InvalidDataException("The format of the torrent meta-data is invalid. Expected a file size.");
}
string fileMD5HashHex;
byte[] fileMD5Hash = null;
if (fileItem.TryGetString("md5sum", out fileMD5HashHex) && fileMD5HashHex.Length == 32)
{
fileMD5Hash = HexHelper.HexToBytes(fileMD5HashHex);
}
BEncoding.List pathList;
if (!fileItem.TryGetList("path", out pathList))
{
throw new InvalidDataException("The format of the torrent meta-data is invalid. Expected a file path.");
}
int pathPartCount = pathList.Count;
string[] pathParts = new string[pathPartCount];
for (int j = 0; j < pathPartCount; j++)
{
string pathPart = pathList.GetString(j);
if (string.IsNullOrEmpty(pathPart))
{
throw new InvalidDataException("The format of the torrent meta-data is invalid. Expected a file path.");
}
pathParts[j] = pathPart;
}
string filePath = string.Join("/", pathParts);
files[i] = new FileItem(filePath, fileSize, fileMD5Hash);
}
}
else
{
long fileSize;
if (!info.TryGetInteger("length", out fileSize))
{
throw new InvalidDataException("The file length is missing in the torrent meta-data. But it is required for single-file torrents.");
}
string fileMD5HashHex;
byte[] fileMD5Hash = null;
if (info.TryGetString("md5sum", out fileMD5HashHex) && fileMD5HashHex.Length == 32)
{
fileMD5Hash = HexHelper.HexToBytes(fileMD5HashHex);
}
files = new FileItem[]
{
new FileItem(name, fileSize, fileMD5Hash)
};
}
totalSize = ComputeTotalSize();
int expectedPieceCount = (int)((totalSize - 1) / pieceSize) + 1;
if (expectedPieceCount != pieceHashes.Length)
{
throw new InvalidOperationException(string.Format("The calculated number of pieces is {0} while there are {1} piece hashes.", expectedPieceCount, pieceHashes.Length));
}
}
