wiz0u/WTelegramClient
1
0
Fork 0
mirror of https://github.com/wiz0u/WTelegramClient.git synced 2026-01-29 03:34:19 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity

Fix issue with SHA computation under .NET Framework

Browse source
This commit is contained in:
Wizou 2021-09-02 00:00:54 +02:00
parent cd6d813845
commit 832e2143f5
2 changed files with 16 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
src/Client.cs
View file

@ -353,6 +353,7 @@ namespace WTelegram
throw new ApplicationException($"Mismatch between MsgKey & decrypted SHA1");
#else
if (decrypted_data.Length - 32 - length is < 12 or > 1024) throw new ApplicationException($"Unexpected decrypted message_data_length {length} / {decrypted_data.Length - 32}");
Sha256Recv.Initialize();
Sha256Recv.TransformBlock(_session.AuthKey, 96, 32, null, 0);
Sha256Recv.TransformFinalBlock(decrypted_data, 0, decrypted_data.Length);
if (!data.AsSpan(8, 16).SequenceEqual(Sha256Recv.Hash.AsSpan(8, 16)))

15
src/Encryption.cs
View file

@ -177,13 +177,16 @@ namespace WTelegram
static (byte[] key, byte[] iv) ConstructTmpAESKeyIV(Int128 server_nonce, Int256 new_nonce)
{
byte[] tmp_aes_key = new byte[32], tmp_aes_iv = new byte[32];
Sha1.Initialize();
Sha1.TransformBlock(new_nonce, 0, 32, null, 0);
Sha1.TransformFinalBlock(server_nonce, 0, 16);
Sha1.Hash.CopyTo(tmp_aes_key, 0); // tmp_aes_key := SHA1(new_nonce + server_nonce)
Sha1.Initialize();
Sha1.TransformBlock(server_nonce, 0, 16, null, 0);
Sha1.TransformFinalBlock(new_nonce, 0, 32);
Array.Copy(Sha1.Hash, 0, tmp_aes_key, 20, 12); // + SHA1(server_nonce, new_nonce)[0:12]
Array.Copy(Sha1.Hash, 12, tmp_aes_iv, 0, 8); // tmp_aes_iv != SHA1(server_nonce, new_nonce)[12:8]
Sha1.Initialize();
Sha1.TransformBlock(new_nonce, 0, 32, null, 0);
Sha1.TransformFinalBlock(new_nonce, 0, 32);
Sha1.Hash.CopyTo(tmp_aes_iv, 8); // + SHA(new_nonce + new_nonce)
@ -281,16 +284,20 @@ j4WcDuXc2CTHgH8gFTNhp/Y8/SpDOhvn9QIDAQAB
byte[] aes_key = new byte[32], aes_iv = new byte[32];
#if MTPROTO1
var sha1 = encrypt ? Sha1 : Sha1Recv;
sha1.Initialize();
sha1.TransformBlock(msgKeyLarge, 4, 16, null, 0); // msgKey
sha1.TransformFinalBlock(authKey, x, 32); // authKey[x:32]
var sha1_a = sha1.Hash;
sha1.Initialize();
sha1.TransformBlock(authKey, 32 + x, 16, null, 0); // authKey[32+x:16]
sha1.TransformBlock(msgKeyLarge, 4, 16, null, 0); // msgKey
sha1.TransformFinalBlock(authKey, 48 + x, 16); // authKey[48+x:16]
var sha1_b = sha1.Hash;
sha1.Initialize();
sha1.TransformBlock(authKey, 64 + x, 32, null, 0); // authKey[64+x:32]
sha1.TransformFinalBlock(msgKeyLarge, 4, 16); // msgKey
var sha1_c = sha1.Hash;
sha1.Initialize();
sha1.TransformBlock(msgKeyLarge, 4, 16, null, 0); // msgKey
sha1.TransformFinalBlock(authKey, 96 + x, 32); // authKey[96+x:32]
var sha1_d = sha1.Hash;
@ -303,9 +310,11 @@ j4WcDuXc2CTHgH8gFTNhp/Y8/SpDOhvn9QIDAQAB
Array.Copy(sha1_d, 0, aes_iv, 24, 8);
#else
var sha256 = encrypt ? Sha256 : Sha256Recv;
sha256.Initialize();
sha256.TransformBlock(msgKeyLarge, 8, 16, null, 0); // msgKey
sha256.TransformFinalBlock(authKey, x, 36); // authKey[x:36]
var sha256_a = sha256.Hash;
sha256.Initialize();
sha256.TransformBlock(authKey, 40 + x, 36, null, 0); // authKey[40+x:36]
sha256.TransformFinalBlock(msgKeyLarge, 8, 16); // msgKey
var sha256_b = sha256.Hash;
@ -365,10 +374,12 @@ j4WcDuXc2CTHgH8gFTNhp/Y8/SpDOhvn9QIDAQAB
var g_256 = g.To256Bytes();
ValidityChecks(p, algo.g);
Sha256.Initialize();
Sha256.TransformBlock(algo.salt1, 0, algo.salt1.Length, null, 0);
Sha256.TransformBlock(passwordBytes, 0, passwordBytes.Length, null, 0);
Sha256.TransformFinalBlock(algo.salt1, 0, algo.salt1.Length);
var hash = Sha256.Hash;
Sha256.Initialize();
Sha256.TransformBlock(algo.salt2, 0, algo.salt2.Length, null, 0);
Sha256.TransformBlock(hash, 0, 32, null, 0);
Sha256.TransformFinalBlock(algo.salt2, 0, algo.salt2.Length);
@ -379,11 +390,13 @@ j4WcDuXc2CTHgH8gFTNhp/Y8/SpDOhvn9QIDAQAB
#else
var pbkdf2 = PBKDF2_SHA512(hash, algo.salt1, 100000, 64);
#endif
Sha256.Initialize();
Sha256.TransformBlock(algo.salt2, 0, algo.salt2.Length, null, 0);
Sha256.TransformBlock(pbkdf2, 0, 64, null, 0);
Sha256.TransformFinalBlock(algo.salt2, 0, algo.salt2.Length);
var x = BigEndianInteger(Sha256.Hash);
Sha256.Initialize();
Sha256.TransformBlock(algo.p, 0, 256, null, 0);
Sha256.TransformFinalBlock(g_256, 0, 256);
var k = BigEndianInteger(Sha256.Hash);
@ -394,6 +407,7 @@ j4WcDuXc2CTHgH8gFTNhp/Y8/SpDOhvn9QIDAQAB
var g_a = BigInteger.ModPow(g, a, p);
var g_a_256 = g_a.To256Bytes();
Sha256.Initialize();
Sha256.TransformBlock(g_a_256, 0, 256, null, 0);
Sha256.TransformFinalBlock(g_b_256, 0, 256);
var u = BigEndianInteger(Sha256.Hash);
@ -408,6 +422,7 @@ j4WcDuXc2CTHgH8gFTNhp/Y8/SpDOhvn9QIDAQAB
for (int i = 0; i < 32; i++) hash[i] ^= h2[i];
var hs1 = Sha256.ComputeHash(algo.salt1);
var hs2 = Sha256.ComputeHash(algo.salt2);
Sha256.Initialize();
Sha256.TransformBlock(hash, 0, 32, null, 0);
Sha256.TransformBlock(hs1, 0, 32, null, 0);
Sha256.TransformBlock(hs2, 0, 32, null, 0);