Crypto: Code review cleanup.

Author: bdrodes

cpp/ql/lib/experimental/quantum/OpenSSL/AlgorithmInstances/KeyAgreementAlgorithmInstance.qll

@@ -22,12 +22,12 @@ predicate knownOpenSSLConstantToKeyAgreementFamilyType(
   )
 }
 
-class KnownOpenSSLHashConstantAlgorithmInstance extends OpenSSLAlgorithmInstance,
+class KnownOpenSSLKeyAgreementConstantAlgorithmInstance extends OpenSSLAlgorithmInstance,
   Crypto::KeyAgreementAlgorithmInstance instanceof KnownOpenSSLKeyAgreementAlgorithmExpr
 {
   OpenSSLAlgorithmValueConsumer getterCall;
 
-  KnownOpenSSLHashConstantAlgorithmInstance() {
+  KnownOpenSSLKeyAgreementConstantAlgorithmInstance() {
     // Two possibilities:
     // 1) The source is a literal and flows to a getter, then we know we have an instance
     // 2) The source is a KnownOpenSSLAlgorithm is call, and we know we have an instance immediately from that
@@ -44,7 +44,6 @@ class KnownOpenSSLHashConstantAlgorithmInstance extends OpenSSLAlgorithmInstance
     or
     // Possibility 2:
     this instanceof OpenSSLAlgorithmCall and
-    this instanceof DirectAlgorithmValueConsumer and
     getterCall = this
   }
 

cpp/ql/lib/experimental/quantum/OpenSSL/AlgorithmInstances/MACAlgorithmInstance.qll

@@ -19,7 +19,7 @@ class KnownOpenSSLMACConstantAlgorithmInstance extends OpenSSLAlgorithmInstance,
     this instanceof OpenSSLAlgorithmLiteral and
     exists(DataFlow::Node src, DataFlow::Node sink |
       // Sink is an argument to a CipherGetterCall
-      sink = getterCall.(OpenSSLAlgorithmValueConsumer).getInputNode() and
+      sink = getterCall.getInputNode() and
       // Source is `this`
       src.asExpr() = this and
       // This traces to a getter

cpp/ql/lib/experimental/quantum/OpenSSL/AlgorithmValueConsumers/DirectAlgorithmValueConsumer.qll

@@ -12,9 +12,6 @@ private import experimental.quantum.OpenSSL.AlgorithmValueConsumers.OpenSSLAlgor
  */
 class DirectAlgorithmValueConsumer extends OpenSSLAlgorithmValueConsumer instanceof OpenSSLAlgorithmCall
 {
-  DataFlow::Node resultNode;
-  Expr resultExpr;
-
   /**
    * These cases take in no explicit value (the value is implicit)
    */

cpp/ql/lib/experimental/quantum/OpenSSL/AlgorithmValueConsumers/HashAlgorithmValueConsumer.qll

@@ -28,7 +28,7 @@ class EVP_Q_Digest_Algorithm_Consumer extends HashAlgorithmValueConsumer {
 }
 
 /**
- *  Instances from https://docs.openssl.org/3.0/man3/EVP_PKEY_CTX_ctrl/
+ * An instance from https://docs.openssl.org/3.0/man3/EVP_PKEY_CTX_ctrl/
  * where the digest is directly consumed by name.
  * In these cases, the operation is not yet performed, but there is
  * these functions are treated as 'initializers' and track the algorithm through
@@ -71,7 +71,7 @@ class EVPDigestAlgorithmValueConsumer extends HashAlgorithmValueConsumer {
         ] and
       valueArgNode.asExpr() = this.(Call).getArgument(0)
       or
-      this.(Call).getTarget().getName() in ["EVP_MD_fetch"] and
+      this.(Call).getTarget().getName() = "EVP_MD_fetch" and
       valueArgNode.asExpr() = this.(Call).getArgument(1)
       or
       this.(Call).getTarget().getName() = "EVP_DigestSignInit_ex" and

cpp/ql/lib/experimental/quantum/OpenSSL/AvcFlow.qll

@@ -1,5 +1,5 @@
 import semmle.code.cpp.dataflow.new.DataFlow
-import experimental.quantum.OpenSSL.AlgorithmValueConsumers.OpenSSLAlgorithmValueConsumers
+private import experimental.quantum.OpenSSL.AlgorithmValueConsumers.OpenSSLAlgorithmValueConsumers
 
 /**
  * Flows from algorithm values to operations, specific to OpenSSL

cpp/ql/lib/experimental/quantum/OpenSSL/CtxFlow.qll

@@ -66,10 +66,8 @@ class CtxPointerArgument extends CtxPointerExpr {
 /**
  * A call returning a CtxPointerExpr.
  */
-private class CtxPointerReturn extends CtxPointerExpr {
-  CtxPointerReturn() { exists(Call c | c = this) }
-
-  Call getCall() { result = this.(Call) }
+private class CtxPointerReturn extends CtxPointerExpr instanceof Call {
+  Call getCall() { result = this }
 }
 
 /**

cpp/ql/lib/experimental/quantum/OpenSSL/KeyFlow.qll

@@ -12,9 +12,7 @@ module OpenSSLKeyFlowConfig implements DataFlow::ConfigSig {
     exists(Crypto::KeyCreationOperationInstance keygen | keygen.getOutputKeyArtifact() = source)
   }
 
-  predicate isSink(DataFlow::Node sink) {
-    exists(Call call | call.(Call).getAnArgument() = sink.asExpr())
-  }
+  predicate isSink(DataFlow::Node sink) { exists(Call call | call.getAnArgument() = sink.asExpr()) }
   //TODO: consideration for additional flow steps? Can a key be copied for example?
 }
 

cpp/ql/lib/experimental/quantum/OpenSSL/Operations/EVPKeyGenOperation.qll

@@ -2,7 +2,6 @@ private import experimental.quantum.Language
 private import experimental.quantum.OpenSSL.CtxFlow
 private import OpenSSLOperationBase
 private import experimental.quantum.OpenSSL.AlgorithmValueConsumers.OpenSSLAlgorithmValueConsumers
-private import semmle.code.cpp.dataflow.new.DataFlow
 
 class EVPKeyGenInitialize extends EvpPrimaryAlgorithmInitializer {
   EVPKeyGenInitialize() {
@@ -13,7 +12,8 @@ class EVPKeyGenInitialize extends EvpPrimaryAlgorithmInitializer {
   }
 
   /**
-   * The algorithm is encoded through the context argument.
+   * Gets the algorithm argument.
+   * In this case the algorithm is encoded through the context argument.
    * The context may be directly created from an algorithm consumer,
    * or from a new operation off of a prior key. Either way,
    * we will treat this argument as the algorithm argument.
@@ -67,8 +67,8 @@ class EVPKeyGenOperation extends EvpOperation, Crypto::KeyGenerationOperationIns
 }
 
 /**
- * Calls to `EVP_PKEY_new_mac_key` create a new MAC key.
- * EVP_PKEY *EVP_PKEY_new_mac_key(int type, ENGINE *e, const unsigned char *key, int keylen);
+ * A call to `EVP_PKEY_new_mac_key` that creatse a new generic MAC key.
+ * Signature: EVP_PKEY *EVP_PKEY_new_mac_key(int type, ENGINE *e, const unsigned char *key, int keylen);
  */
 class EvpNewMacKey extends EvpOperation, Crypto::KeyGenerationOperationInstance {
   DataFlow::Node keyResultNode;

cpp/ql/lib/experimental/quantum/OpenSSL/Operations/EVPPKeyCtxInitializer.qll

@@ -8,7 +8,6 @@
 import cpp
 private import experimental.quantum.OpenSSL.CtxFlow
 private import OpenSSLOperations
-private import OpenSSLOperationBase
 
 /**
  * A call to `EVP_PKEY_CTX_new` or `EVP_PKEY_CTX_new_from_pkey`.
@@ -17,7 +16,7 @@ private import OpenSSLOperationBase
  * parameters set (e.g., `EVP_PKEY_paramgen`).
  * NOTE: for the case of `EVP_PKEY_paramgen`, these calls
  * are encoded as context passthroughs, and any operation
- * will get all associated initializers for teh paramgen
+ * will get all associated initializers for the paramgen
  * at the final keygen operation automatically.
  */
 class EVPNewKeyCtx extends EvpKeyInitializer {

cpp/ql/lib/experimental/quantum/OpenSSL/Operations/EVPSignatureOperation.qll

@@ -3,7 +3,6 @@
  */
 
 private import experimental.quantum.Language
-private import OpenSSLOperationBase
 private import experimental.quantum.OpenSSL.AvcFlow
 private import experimental.quantum.OpenSSL.CtxFlow
 private import experimental.quantum.OpenSSL.AlgorithmValueConsumers.OpenSSLAlgorithmValueConsumers
@@ -87,7 +86,7 @@ private Expr signatureOperationOutputArg(Call call) {
 }
 
 /**
- * Base configuration for all EVP signature operations.
+ * The base configuration for all EVP signature operations.
  */
 abstract class EvpSignatureOperation extends EvpOperation, Crypto::SignatureOperationInstance {
   EvpSignatureOperation() {