void UpdateCachedFields(BufRef reader)
{
CachedKey = new I2PIdentHash(reader);
CachedFrom = new I2PIdentHash(reader);
CachedLookupType = (LookupTypes)reader.Read8();
if (((byte)CachedLookupType & 0x01) != 0)
{
CachedTunnelId = new I2PTunnelId(reader);
}
var excludecount = reader.ReadFlip16();
for (int i = 0; i < excludecount; ++i)
{
CachedExcludeList.Add(new DatabaseSearchReplyMessage(reader));
}
if (((byte)CachedLookupType & 0x02) != 0)
{
CachedReplyKey = new I2PSessionKey(reader);
var tagcount = reader.Read8();
CachedTags.Add(new I2PSessionTag(reader));
}
}
public static GarlicMessage AESEncryptGarlic(
Garlic msg,
I2PSessionKey sessionkey,
I2PSessionTag tag,
List <I2PSessionTag> newtags)
{
var cipher = new CbcBlockCipher(new AesEngine());
var payload = msg.ToByteArray();
var dest = new BufLen(new byte[65536]);
// Reserve header + 4 bytes for GarlicMessageLength
var writer = new BufRefLen(dest, I2NPMaxHeaderSize + 4);
// Tag as header
writer.Write(tag.Value);
// AES block
var aesstart = new BufLen(writer);
var aesblock = new GarlicAESBlock(writer, newtags, null, new BufRefLen(payload));
var pivh = I2PHashSHA256.GetHash(tag.Value);
cipher.Init(true, sessionkey.Key.ToParametersWithIV(new BufLen(pivh, 0, 16)));
cipher.ProcessBytes(aesblock.DataBuf);
var length = writer - dest;
dest.PokeFlip32((uint)(length - 4), I2NPMaxHeaderSize);
return(new GarlicMessage(new BufRefLen(dest, I2NPMaxHeaderSize, length)));
}
public static (GarlicAESBlock, I2PSessionKey) EGDecryptGarlic(
GarlicMessage garlic,
I2PPrivateKey privkey)
{
var cipher = new CbcBlockCipher(new AesEngine());
var egdata = garlic.EGData;
var egbuf = new BufLen(egdata, 0, 514);
var egheader = ElGamalCrypto.Decrypt(egbuf, privkey, true);
var sessionkey = new I2PSessionKey(new BufLen(egheader, 0, 32));
var preiv = new BufLen(egheader, 32, 32);
var egpadding = new BufLen(egheader, 64, 158);
var aesbuf = new BufLen(egdata, 514);
var pivh = I2PHashSHA256.GetHash(preiv);
cipher.Init(false, sessionkey.Key.ToParametersWithIV(new BufLen(pivh, 0, 16)));
cipher.ProcessBytes(aesbuf);
GarlicAESBlock aesblock =
new GarlicAESBlock(new BufRefLen(aesbuf));
if (!aesblock.VerifyPayloadHash())
{
throw new ChecksumFailureException("AES block hash check failed!");
}
return(aesblock, sessionkey);
}
public GarlicCloveDeliveryLocal(BufRef reader, byte flag) : base(DeliveryMethod.Local)
{
Flag = flag;
if ((Flag & (byte)DeliveryFlags.Encrypted) != 0)
{
SessionKey = new I2PSessionKey(reader);
}
if ((Flag & (byte)DeliveryFlags.Delay) != 0)
{
Delay = reader.ReadFlip32();
}
}
public GarlicCloveDeliveryRouter(BufRef reader, byte flag) : base(DeliveryMethod.Router)
{
Flag = flag;
if ((Flag & (byte)DeliveryFlags.Encrypted) != 0)
{
SessionKey = new I2PSessionKey(reader);
}
Destination = new I2PIdentHash(reader);
if ((Flag & (byte)DeliveryFlags.Delay) != 0)
{
Delay = reader.ReadFlip32();
}
}
public GarlicAESBlock(
BufRefLen reader,
IList <I2PSessionTag> tags,
I2PSessionKey newsessionkey,
BufRefLen payload)
{
var start = new BufLen(reader);
// Allocate
TagCount = reader.ReadBufLen(2);
if (tags != null)
{
for (int i = 0; i < tags.Count; ++i)
{
Tags.Add(reader.ReadBufLen(I2PSessionTag.TagLength));
}
}
PayloadSize = reader.ReadBufLen(4);
PayloadHash = reader.ReadBufLen(32);
Flag = reader.ReadBufLen(1);
if (newsessionkey != null)
{
reader.ReadBufLen(32);
}
var pllen = Math.Min(reader.Length, payload.Length);
Payload = reader.ReadBufLen(pllen);
Padding = reader.ReadBufLen(BufUtils.Get16BytePadding(reader - start));
// Write
TagCount.PokeFlip16((ushort)(tags == null ? 0 : tags.Count), 0);
if (tags != null)
{
for (int i = 0; i < tags.Count; ++i)
{
Tags[i].Poke(tags[i].Value, 0);
}
}
Flag[0] = (byte)(newsessionkey != null ? 0x01 : 0);
if (newsessionkey != null)
{
NewSessionKey.Poke(newsessionkey.Key, 0);
}
Payload.Poke(new BufLen(payload, 0, pllen), 0);
payload.Seek(pllen);
PayloadSize.PokeFlip32((uint)pllen, 0);
PayloadHash.Poke(I2PHashSHA256.GetHash(Payload), 0);
Padding.Randomize();
DataBuf = new BufLen(start, 0, reader - start);
}
public void TestEncodeDecodeAES()
{
var m1 = new DeliveryStatusMessage(0x4321);
var m2 = new DeliveryStatusMessage(0xa3c2);
var garlic = new Garlic(
new GarlicClove(
new GarlicCloveDeliveryDestination(
m1,
Destination.IdentHash)),
new GarlicClove(
new GarlicCloveDeliveryDestination(
m2,
Destination.IdentHash))
);
// No tags
var sessionkey = new I2PSessionKey();
var sessiontag = new I2PSessionTag();
var cg = Garlic.AESEncryptGarlic(garlic, sessionkey, sessiontag, null);
var egdata = I2NPMessage.Clone(cg);
var(aesblock, sk) = Garlic.RetrieveAESBlock(egdata, Private, (t) => sessionkey);
var g2 = new Garlic((BufRefLen)aesblock.Payload);
Assert.IsTrue(BufUtils.Equal(garlic.ToByteArray(), g2.ToByteArray()));
// With tags
var tags = new List <I2PSessionTag>();
for (int i = 0; i < 30; ++i)
{
tags.Add(new I2PSessionTag());
}
cg = Garlic.AESEncryptGarlic(garlic, sessionkey, sessiontag, null);
egdata = I2NPMessage.Clone(cg);
(aesblock, sk) = Garlic.RetrieveAESBlock(egdata, Private, (t) => sessionkey);
g2 = new Garlic((BufRefLen)aesblock.Payload);
Assert.IsTrue(BufUtils.Equal(garlic.ToByteArray(), g2.ToByteArray()));
}
public static GarlicMessage EGEncryptGarlic(
Garlic msg,
I2PPublicKey pubkey,
I2PSessionKey sessionkey,
List <I2PSessionTag> newtags)
{
var cipher = new CbcBlockCipher(new AesEngine());
var payload = msg.ToByteArray();
var dest = new BufLen(new byte[65536]);
// Reserve header + 4 bytes for GarlicMessageLength
var writer = new BufRefLen(dest, I2NPMaxHeaderSize + 4);
// ElGamal block
var egbuf = new BufLen(new byte[222]);
var sessionkeybuf = new BufLen(egbuf, 0, 32);
var preivbuf = new BufLen(egbuf, 32, 32);
var egpadding = new BufLen(egbuf, 64, 158);
egpadding.Randomize();
preivbuf.Randomize();
sessionkeybuf.Poke(sessionkey.Key, 0);
var iv = new BufLen(I2PHashSHA256.GetHash(preivbuf), 0, 16);
ElGamalCrypto.Encrypt(writer, egbuf, pubkey, true);
// AES block
var aesstart = new BufLen(writer);
var aesblock = new GarlicAESBlock(writer, newtags, null, new BufRefLen(payload));
cipher.Init(true, sessionkey.Key.ToParametersWithIV(iv));
cipher.ProcessBytes(aesblock.DataBuf);
var length = writer - dest;
dest.PokeFlip32((uint)(length - 4), I2NPMaxHeaderSize);
return(new GarlicMessage(new BufRefLen(dest, I2NPMaxHeaderSize, length)));
}
public GarlicAESBlock(BufRefLen reader)
{
var start = new BufLen(reader);
TagCount = reader.ReadBufLen(2);
var tags = TagCount.PeekFlip16(0);
if (tags > 0)
{
if (tags * I2PSessionTag.TagLength > start.Length)
{
throw new ArgumentException("GarlicAESBlock: Not enough data for the tags supplied.");
}
for (int i = 0; i < tags; ++i)
{
Tags.Add(reader.ReadBufLen(I2PSessionTag.TagLength));
}
}
PayloadSize = reader.ReadBufLen(4);
PayloadHash = reader.ReadBufLen(32);
Flag = reader.ReadBufLen(1);
if (Flag[0] != 0)
{
NewSessionKey = new I2PSessionKey(reader.ReadBufLen(32));
}
var pllen = PayloadSize.PeekFlip32(0);
if (pllen > reader.Length)
{
throw new ArgumentException("GarlicAESBlock: Not enough data payload supplied.");
}
Payload = reader.ReadBufLen((int)pllen);
Padding = reader.ReadBufLen(BufUtils.Get16BytePadding(reader - start));
DataBuf = new BufLen(start, 0, reader - start);
}
public void Reset()
{
SessionKey = new I2PSessionKey();
lock (SessionTags) SessionTags.Clear();
}
public Garlic DecryptMessage(EGGarlic message)
{
lock ( SessionTags )
{
var old = SessionTags.Where(p => p.Key.Created.DeltaToNow.ToMinutes > (I2PSessionTag.TagLifetimeMinutes + 2)).ToArray();
foreach (var one in old)
{
SessionTags.Remove(one.Key);
}
}
var egdata = message.EGData;
var tag = new I2PSessionTag(new BufRefLen(egdata, 0, 32));
I2PSessionKey sessionkey;
bool found;
lock ( SessionTags )
{
found = SessionTags.TryGetValue(tag, out sessionkey);
}
BufLen aesbuf;
if (found)
{
aesbuf = new BufLen(egdata, 32);
lock ( SessionTags )
{
SessionTags.Remove(tag);
}
#if LOG_ALL_TUNNEL_TRANSFER
DebugUtils.LogDebug("ReceivedSessions: Working tag found for EGarlic.");
#endif
var pivh = I2PHashSHA256.GetHash(tag.Value);
Cipher.Init(false, sessionkey.Key.ToParametersWithIV(new BufLen(pivh, 0, 16)));
Cipher.ProcessBytes(aesbuf);
}
else
{
BufLen egheader;
try
{
var egbuf = new BufLen(egdata, 0, 514);
egheader = ElGamalCrypto.Decrypt(egbuf, Key, true);
}
catch (Exception ex)
{
DebugUtils.Log("ReceivedSessions", ex);
return(null);
}
#if LOG_ALL_TUNNEL_TRANSFER
DebugUtils.LogDebug("ReceivedSessions: Using ElGamal to decrypt.");
#endif
sessionkey = new I2PSessionKey(new BufLen(egheader, 0, 32));
var preiv = new BufLen(egheader, 32, 32);
var egpadding = new BufLen(egheader, 64);
aesbuf = new BufLen(egdata, 514);
var pivh = I2PHashSHA256.GetHash(preiv);
Cipher.Init(false, sessionkey.Key.ToParametersWithIV(new BufLen(pivh, 0, 16)));
Cipher.ProcessBytes(aesbuf);
}
GarlicAESBlock aesblock;
try
{
aesblock = new GarlicAESBlock(new BufRefLen(aesbuf));
}
catch (Exception ex)
{
DebugUtils.Log("ReceivedSessions", ex);
return(null);
}
if (!aesblock.VerifyPayloadHash())
{
DebugUtils.LogDebug("ReceivedSessions: DecryptMessage: AES block SHA256 check failed.");
return(null);
}
#if LOG_ALL_TUNNEL_TRANSFER
DebugUtils.LogDebug("ReceivedSessions: Working Aes block received. " + SessionTags.Count.ToString() + " tags available.");
#endif
if (aesblock.Tags.Count > 0)
{
#if LOG_ALL_TUNNEL_TRANSFER
DebugUtils.LogDebug("ReceivedSessions: " + aesblock.Tags.Count.ToString() + " new tags received.");
#endif
lock ( SessionTags )
{
foreach (var onetag in aesblock.Tags.ToArray())
{
SessionTags[new I2PSessionTag(new BufRef(onetag))] = sessionkey;
}
}
}
return(new Garlic((BufRefLen)aesblock.Payload));
}