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Crypto: Added Signature algorithm instance and consumer
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+137
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‎cpp/ql/lib/experimental/quantum/OpenSSL/AlgorithmInstances/SignatureAlgorithmInstance.qll

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import cpp
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private import experimental.quantum.Language
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private import KnownAlgorithmConstants
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private import Crypto::KeyOpAlg as KeyOpAlg
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private import OpenSSLAlgorithmInstanceBase
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private import experimental.quantum.OpenSSL.AlgorithmValueConsumers.OpenSSLAlgorithmValueConsumerBase
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private import experimental.quantum.OpenSSL.AlgorithmValueConsumers.DirectAlgorithmValueConsumer
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private import AlgToAVCFlow
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/**
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* Gets the signature algorithm type based on the normalized algorithm name.
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*/
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private predicate knownOpenSSLConstantToSignatureFamilyType(
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KnownOpenSSLSignatureAlgorithmExpr e, Crypto::KeyOpAlg::TAlgorithm type
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) {
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exists(string name |
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name = e.(KnownOpenSSLAlgorithmExpr).getNormalizedName() and
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(
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name.matches("RSA%") and type = KeyOpAlg::TAsymmetricCipher(KeyOpAlg::RSA())
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or
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name.matches("DSA%") and type = KeyOpAlg::TSignature(KeyOpAlg::DSA())
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or
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name.matches("ECDSA%") and type = KeyOpAlg::TSignature(KeyOpAlg::ECDSA())
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or
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name.matches("ED25519%") and type = KeyOpAlg::TSignature(KeyOpAlg::EDDSA())
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or
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name.matches("ED448%") and type = KeyOpAlg::TSignature(KeyOpAlg::EDDSA())
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)
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)
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}
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/**
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* A signature algorithm instance derived from an OpenSSL constant.
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*/
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class KnownOpenSSLSignatureConstantAlgorithmInstance extends OpenSSLAlgorithmInstance,
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Crypto::KeyOperationAlgorithmInstance instanceof KnownOpenSSLSignatureAlgorithmExpr
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{
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OpenSSLAlgorithmValueConsumer getterCall;
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KnownOpenSSLSignatureConstantAlgorithmInstance() {
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// Two possibilities:
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// 1) The source is a literal and flows to a getter, then we know we have an instance
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// 2) The source is a KnownOpenSSLAlgorithm call, and we know we have an instance immediately from that
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// Possibility 1:
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this instanceof KnownOpenSSLPaddingAlgorithmExpr and
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exists(DataFlow::Node src, DataFlow::Node sink |
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// Sink is an argument to a signature getter call
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sink = getterCall.getInputNode() and
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// Source is `this`
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src.asExpr() = this and
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// This traces to a getter
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KnownOpenSSLAlgorithmToAlgorithmValueConsumerFlow::flow(src, sink)
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)
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or
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// Possibility 2:
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this instanceof OpenSSLAlgorithmCall and
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getterCall = this
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}
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override Crypto::ModeOfOperationAlgorithmInstance getModeOfOperationAlgorithm() { none() }
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override Crypto::PaddingAlgorithmInstance getPaddingAlgorithm() { none() }
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override string getRawAlgorithmName() {
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result = this.(Literal).getValue().toString()
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or
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result = this.(Call).getTarget().getName()
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}
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override int getKeySizeFixed() {
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// TODO: use ellipticCurveNameToKeySizeAndFamilyMapping or KnownOpenSSLEllipticCurveConstantAlgorithmInstance
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// TODO: maybe add getExplicitKeySize to KnownOpenSSLSignatureAlgorithmExpr and use it here
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none()
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}
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override KeyOpAlg::Algorithm getAlgorithmType() {
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knownOpenSSLConstantToSignatureFamilyType(this, result)
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or
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not knownOpenSSLConstantToSignatureFamilyType(this, _) and
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result = KeyOpAlg::TSignature(KeyOpAlg::OtherSignatureAlgorithmType())
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}
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override OpenSSLAlgorithmValueConsumer getAVC() { result = getterCall }
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override Crypto::ConsumerInputDataFlowNode getKeySizeConsumer() {
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// TODO: trace to any key size initializer
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// probably PKeyAlgorithmValueConsumer and SignatureAlgorithmValueConsumer
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none()
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}
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/**
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* No mode for signatures.
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*/
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override predicate shouldHaveModeOfOperation() { none() }
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/**
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* Padding only for RSA.
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*/
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override predicate shouldHavePaddingScheme() {
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this.getAlgorithmType() instanceof KeyOpAlg::TAsymmetricCipher
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}
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}

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

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@@ -5,3 +5,4 @@ import PaddingAlgorithmValueConsumer
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import HashAlgorithmValueConsumer
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import EllipticCurveAlgorithmValueConsumer
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import PKeyAlgorithmValueConsumer
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import SignatureAlgorithmValueConsumer

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

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import cpp
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private import experimental.quantum.Language
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private import experimental.quantum.OpenSSL.AlgorithmInstances.KnownAlgorithmConstants
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private import experimental.quantum.OpenSSL.AlgorithmInstances.OpenSSLAlgorithmInstanceBase
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private import OpenSSLAlgorithmValueConsumerBase
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private import experimental.quantum.OpenSSL.LibraryDetector
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abstract class SignatureAlgorithmValueConsumer extends OpenSSLAlgorithmValueConsumer { }
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class EVPSignatureAlgorithmValueConsumer extends SignatureAlgorithmValueConsumer {
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DataFlow::Node valueArgNode;
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DataFlow::Node resultNode;
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EVPSignatureAlgorithmValueConsumer() {
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resultNode.asExpr() = this and
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(
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// EVP_SIGNATURE
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this.(Call).getTarget().getName() = "EVP_SIGNATURE_fetch" and
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valueArgNode.asExpr() = this.(Call).getArgument(1)
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// EVP_PKEY_get1_DSA, EVP_PKEY_get1_RSA
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// DSA_SIG_new, DSA_SIG_get0, RSA_sign ?
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)
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}
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override DataFlow::Node getResultNode() { result = resultNode }
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override Crypto::ConsumerInputDataFlowNode getInputNode() { result = valueArgNode }
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override Crypto::AlgorithmInstance getAKnownAlgorithmSource() {
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exists(OpenSSLAlgorithmInstance i | i.getAVC() = this and result = i)
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}
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}

‎shared/quantum/codeql/quantum/experimental/Model.qll

Lines changed: 2 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -597,8 +597,7 @@ module CryptographyBase<LocationSig Location, InputSig<Location> Input> {
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newtype TSignatureAlgorithmType =
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DSA() or
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ECDSA() or
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Ed25519() or
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Ed448() or
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EDDSA() or // e.g., ED25519 or ED448
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OtherSignatureAlgorithmType()
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newtype TKEMAlgorithmType =
@@ -703,9 +702,7 @@ module CryptographyBase<LocationSig Location, InputSig<Location> Input> {
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or
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type = TSignature(ECDSA()) and name = "ECDSA"
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or
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type = TSignature(Ed25519()) and name = "Ed25519"
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or
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type = TSignature(Ed448()) and name = "Ed448"
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type = TSignature(EDDSA()) and name = "EDSA"
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or
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type = TSignature(OtherSignatureAlgorithmType()) and name = "UnknownSignature"
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or

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