1 files changed, 69 insertions, 0 deletions
diff --git a/unrar/unrar/crypt3.cpp b/unrar/unrar/crypt3.cpp
new file mode 100644
index 0000000..e6e3a82
--- /dev/null
+++ b/unrar/unrar/crypt3.cpp
@@ -0,0 +1,69 @@
+void CryptData::SetKey30(bool Encrypt,SecPassword *Password,const wchar *PwdW,const byte *Salt)
+{
+  byte AESKey[16],AESInit[16];
+
+  bool Cached=false;
+  for (uint I=0;I<ASIZE(KDF3Cache);I++)
+    if (KDF3Cache[I].Pwd==*Password &&
+        (Salt==NULL && !KDF3Cache[I].SaltPresent || Salt!=NULL &&
+        KDF3Cache[I].SaltPresent && memcmp(KDF3Cache[I].Salt,Salt,SIZE_SALT30)==0))
+    {
+      memcpy(AESKey,KDF3Cache[I].Key,sizeof(AESKey));
+      SecHideData(AESKey,sizeof(AESKey),false,false);
+      memcpy(AESInit,KDF3Cache[I].Init,sizeof(AESInit));
+      Cached=true;
+      break;
+    }
+
+  if (!Cached)
+  {
+    byte RawPsw[2*MAXPASSWORD+SIZE_SALT30];
+    size_t PswLength=wcslen(PwdW);
+    size_t RawLength=2*PswLength;
+    WideToRaw(PwdW,PswLength,RawPsw,RawLength);
+    if (Salt!=NULL)
+    {
+      memcpy(RawPsw+RawLength,Salt,SIZE_SALT30);
+      RawLength+=SIZE_SALT30;
+    }
+    sha1_context c;
+    sha1_init(&c);
+
+    const uint HashRounds=0x40000;
+    for (uint I=0;I<HashRounds;I++)
+    {
+      sha1_process_rar29( &c, RawPsw, RawLength );
+      byte PswNum[3];
+      PswNum[0]=(byte)I;
+      PswNum[1]=(byte)(I>>8);
+      PswNum[2]=(byte)(I>>16);
+      sha1_process(&c, PswNum, 3);
+      if (I%(HashRounds/16)==0)
+      {
+        sha1_context tempc=c;
+        uint32 digest[5];
+        sha1_done( &tempc, digest );
+        AESInit[I/(HashRounds/16)]=(byte)digest[4];
+      }
+    }
+    uint32 digest[5];
+    sha1_done( &c, digest );
+    for (uint I=0;I<4;I++)
+      for (uint J=0;J<4;J++)
+        AESKey[I*4+J]=(byte)(digest[I]>>(J*8));
+
+    KDF3Cache[KDF3CachePos].Pwd=*Password;
+    if ((KDF3Cache[KDF3CachePos].SaltPresent=(Salt!=NULL))==true)
+      memcpy(KDF3Cache[KDF3CachePos].Salt,Salt,SIZE_SALT30);
+    memcpy(KDF3Cache[KDF3CachePos].Key,AESKey,sizeof(AESKey));
+    SecHideData(KDF3Cache[KDF3CachePos].Key,sizeof(KDF3Cache[KDF3CachePos].Key),true,false);
+    memcpy(KDF3Cache[KDF3CachePos].Init,AESInit,sizeof(AESInit));
+    KDF3CachePos=(KDF3CachePos+1)%ASIZE(KDF3Cache);
+
+    cleandata(RawPsw,sizeof(RawPsw));
+  }
+  rin.Init(Encrypt, AESKey, 128, AESInit);
+  cleandata(AESKey,sizeof(AESKey));
+  cleandata(AESInit,sizeof(AESInit));
+}
+