Updates to insecure or unknown nonce at operation.

Author: bdrodes

java/ql/src/experimental/Quantum/InsecureOrUnknownNonceAtOperation.ql

@@ -6,52 +6,47 @@
 
 import experimental.Quantum.Language
 
-
 from Crypto::NonceNode n, Crypto::CipherOperationNode op, Crypto::FlowAwareElement src, string msg
 where
   op.getANonce() = n and
+  // Only encryption mode is relevant for insecure nonces, consder any 'unknown' subtype
+  // as possibly encryption. 
+  (
+    op.getCipherOperationSubtype() instanceof Crypto::EncryptionSubtype
+    or
+    op.getCipherOperationSubtype() instanceof Crypto::WrapSubtype
+    or
+    op.getCipherOperationSubtype() instanceof Crypto::UnwrapSubtype 
+  ) and
   (
     // Known sources cases that are not secure
     src = n.getSourceElement() and
-      not src instanceof SecureRandomnessInstance and
-      msg = "Operation uses insecure nonce source $@"
-
+    not src instanceof SecureRandomnessInstance and
+    msg = "Operation uses insecure nonce source $@"
     or
     // Totally unknown sources (unmodeled input sources)
-    not exists(n.getSourceElement()) and msg = "Operation uses unknown nonce source" and src = n.asElement()
+    not exists(n.getSourceElement()) and
+    msg = "Operation uses unknown nonce source" and
+    src = n.asElement()
   )
 select n, msg, src, src.toString()
 
-
 // variant using instances, does not yield the same results
 // from Crypto::NonceArtifactConsumer n, Crypto::CipherOperationInstance op, Crypto::FlowAwareElement src, string msg
 // where
 //   op.getNonceConsumer() = n and
+// TODO: only perform the query on encryption
 //   (
 //     // Known sources cases that are not secure
 //     src = n.getAKnownArtifactSource()and
 //       not src instanceof SecureRandomnessInstance and
 //       msg = "Operation uses insecure nonce source $@"
-
 //     or
 //     // Totally unknown sources (unmodeled input sources)
 //     // When this occurs set src to n, just to bind it, but the output message will not report any source
 //     not exists(n.getAKnownArtifactSource()) and msg = "Operation uses unknown nonce source" and src = n
 //   )
 // select n, msg, src, src.toString()
-
-
-
-
-
-
-
-
-
-
-
-
-
 // NOTE: this will find all unknowns too, constants, and allocations, without needing to model them
 // which is kinda nice, but accidental, since getSourceElement is not modeled for everything
 // If users want to find constants or unallocated, they need to model those sources, and output the
@@ -61,7 +56,6 @@ select n, msg, src, src.toString()
 // will see the nonce and operation are secure, regardless of potentially insecure IV sources
 // resulting in False Negatives
 // NOTE: need to have a query where the op has no Nonce
-
 // // Ideal query
 // from Crypto::NonceNode n, Crypto::CipherOperationNode op
 // where