From 51ca4de68c7b6e6f61994a58147b274a9448bea1 Mon Sep 17 00:00:00 2001
From: Raul Metsma <raul@metsma.ee>
Date: Mon, 5 Aug 2024 23:07:49 +0300
Subject: [PATCH] Take PIN ownership to minimze memory copy-s

followup WE2-479

Signed-off-by: Raul Metsma <raul@metsma.ee>
---
 lib/libelectronic-id                          |  2 +-
 .../command-handlers/authenticate.cpp         | 22 ++++++-------------
 src/controller/command-handlers/sign.cpp      | 18 +++++----------
 3 files changed, 13 insertions(+), 29 deletions(-)

diff --git a/lib/libelectronic-id b/lib/libelectronic-id
index 7991e0ec..261c0d07 160000
--- a/lib/libelectronic-id
+++ b/lib/libelectronic-id
@@ -1 +1 @@
-Subproject commit 7991e0ecc5839a12d076166f663de5f3c7dcb8c0
+Subproject commit 261c0d07eb60d38e439c42973c2a00a8c6dce54c
diff --git a/src/controller/command-handlers/authenticate.cpp b/src/controller/command-handlers/authenticate.cpp
index 3af44db0..e1af1e04 100644
--- a/src/controller/command-handlers/authenticate.cpp
+++ b/src/controller/command-handlers/authenticate.cpp
@@ -30,7 +30,6 @@
 #include <QJsonDocument>
 #include <QCryptographicHash>
 #include <QDir>
-#include <QScopeGuard>
 
 #include <map>
 
@@ -57,7 +56,7 @@ QVariantMap createAuthenticationToken(const QString& signatureAlgorithm,
 }
 
 QByteArray createSignature(const QString& origin, const QString& challengeNonce,
-                           const ElectronicID& eid, const pcsc_cpp::byte_vector& pin)
+                           const ElectronicID& eid, pcsc_cpp::byte_vector&& pin)
 {
     static const std::map<JsonWebSignatureAlgorithm, QCryptographicHash::Algorithm>
         SIGNATURE_ALGO_TO_HASH {
@@ -86,7 +85,7 @@ QByteArray createSignature(const QString& origin, const QString& challengeNonce,
     const pcsc_cpp::byte_vector hashToBeSigned {hashToBeSignedQBytearray.cbegin(),
                                                 hashToBeSignedQBytearray.cend()};
 
-    const auto signature = eid.signWithAuthKey(pin, hashToBeSigned);
+    const auto signature = eid.signWithAuthKey(std::move(pin), hashToBeSigned);
 
     return QByteArray::fromRawData(reinterpret_cast<const char*>(signature.data()),
                                    int(signature.size()))
@@ -120,20 +119,13 @@ Authenticate::Authenticate(const CommandWithArguments& cmd) : CertificateReader(
 QVariantMap Authenticate::onConfirm(WebEidUI* window,
                                     const CardCertificateAndPinInfo& cardCertAndPin)
 {
-    const auto signatureAlgorithm =
-        QString::fromStdString(cardCertAndPin.cardInfo->eid().authSignatureAlgorithm());
-
-    pcsc_cpp::byte_vector pin;
-    getPin(pin, cardCertAndPin.cardInfo->eid(), window);
-    auto pin_cleanup = qScopeGuard([&pin] {
-        // Erase PIN memory.
-        std::fill(pin.begin(), pin.end(), '\0');
-    });
-
     try {
+        const auto signatureAlgorithm =
+            QString::fromStdString(cardCertAndPin.cardInfo->eid().authSignatureAlgorithm());
+        pcsc_cpp::byte_vector pin;
+        getPin(pin, cardCertAndPin.cardInfo->eid(), window);
         const auto signature =
-            createSignature(origin.url(), challengeNonce, cardCertAndPin.cardInfo->eid(), pin);
-
+            createSignature(origin.url(), challengeNonce, cardCertAndPin.cardInfo->eid(), std::move(pin));
         return createAuthenticationToken(signatureAlgorithm, cardCertAndPin.certificateBytesInDer,
                                          signature);
 
diff --git a/src/controller/command-handlers/sign.cpp b/src/controller/command-handlers/sign.cpp
index 5b383aba..2746da90 100644
--- a/src/controller/command-handlers/sign.cpp
+++ b/src/controller/command-handlers/sign.cpp
@@ -25,18 +25,16 @@
 #include "signauthutils.hpp"
 #include "utils/utils.hpp"
 
-#include <QScopeGuard>
-
 using namespace electronic_id;
 
 namespace
 {
 
-QPair<QString, QVariantMap> signHash(const ElectronicID& eid, const pcsc_cpp::byte_vector& pin,
+QPair<QString, QVariantMap> signHash(const ElectronicID& eid, pcsc_cpp::byte_vector&& pin,
                                      const QByteArray& docHash, const HashAlgorithm hashAlgo)
 {
     const auto hashBytes = pcsc_cpp::byte_vector {docHash.begin(), docHash.end()};
-    const auto signature = eid.signWithSigningKey(pin, hashBytes, hashAlgo);
+    const auto signature = eid.signWithSigningKey(std::move(pin), hashBytes, hashAlgo);
 
     const auto signatureBase64 =
         QByteArray::fromRawData(reinterpret_cast<const char*>(signature.first.data()),
@@ -97,16 +95,10 @@ void Sign::emitCertificatesReady(const std::vector<CardCertificateAndPinInfo>& c
 
 QVariantMap Sign::onConfirm(WebEidUI* window, const CardCertificateAndPinInfo& cardCertAndPin)
 {
-    pcsc_cpp::byte_vector pin;
-    getPin(pin, cardCertAndPin.cardInfo->eid(), window);
-    auto pin_cleanup = qScopeGuard([&pin] {
-        // Erase PIN memory.
-        std::fill(pin.begin(), pin.end(), '\0');
-    });
-
     try {
-        const auto signature = signHash(cardCertAndPin.cardInfo->eid(), pin, docHash, hashAlgo);
-
+        pcsc_cpp::byte_vector pin;
+        getPin(pin, cardCertAndPin.cardInfo->eid(), window);
+        const auto signature = signHash(cardCertAndPin.cardInfo->eid(), std::move(pin), docHash, hashAlgo);
         return {{QStringLiteral("signature"), signature.first},
                 {QStringLiteral("signatureAlgorithm"), signature.second}};