File indexing completed on 2024-11-24 04:44:40

 /*
  * SPDX-FileCopyrightText: 2021 Volker Krause <vkrause@kde.org>
  * SPDX-License-Identifier: LGPL-2.0-or-later
  */
 
 #include "irmapublickey_p.h"
 
 #include "openssl/bignum_p.h"
 
 #include <QDebug>
 #include <QFile>
 #include <QXmlStreamReader>
 
 // see https://pkg.go.dev/github.com/privacybydesign/gabi@v0.0.0-20210816093228-75a6590e506c/gabikeys#PublicKey
 
 IrmaPublicKey::IrmaPublicKey() = default;
 
 bool IrmaPublicKey::isValid() const
 {
     return N && Z && S && std::all_of(R.begin(), R.end(), [](const auto &r) { return r.get() != nullptr; });
 }
 
 // see https://github.com/minvws/gabi/blob/idemix_origin/sysparams.go#L21
 int IrmaPublicKey::LePrime() const
 {
     return 120;
 }
 
 int IrmaPublicKey::Lh() const
 {
     return 256;
 }
 
 int IrmaPublicKey::Lm() const
 {
     switch (BN_num_bits(N.get())) {
         case 1024:
         case 2048:
             return 256;
         case 4096:
             return 512;
     }
     return 0;
 }
 
 int IrmaPublicKey::Lstatzk() const
 {
     switch (BN_num_bits(N.get())) {
         case 1024:
             return 80;
         case 2048:
         case 4096:
             return 128;
     }
     return 0;
 }
 
 // and https://github.com/minvws/gabi/blob/idemix_origin/sysparams.go#L60
 int IrmaPublicKey::Le() const
 {
     return Lstatzk() + Lh() + Lm() + 5;
 }
 
 int IrmaPublicKey::LeCommit() const
 {
     return LePrime() + Lstatzk() + Lh();
 }
 
 int IrmaPublicKey::LmCommit() const
 {
     return Lm() + Lstatzk() + Lh();
 }
 
 
 IrmaPublicKey IrmaPublicKeyLoader::load(const QString &keyId)
 {
     IrmaPublicKey pk;
 
     QFile pkFile(QLatin1String(":/org.kde.khealthcertificate/nl-coronacheck/keys/") + keyId + QLatin1String(".xml"));
     if (!pkFile.open(QFile::ReadOnly)) {
         qWarning() << "Failed to find IRMA public key:" << keyId;
         return pk;
     }
 
     QXmlStreamReader reader(&pkFile);
     while (!reader.atEnd() && !reader.hasError()) {
         reader.readNextStartElement();
         if (reader.name() == QLatin1String("n")) {
             pk.N = Bignum::fromDecimalString(reader.readElementText());
         }
         else if (reader.name() == QLatin1String("Z")) {
             pk.Z = Bignum::fromDecimalString(reader.readElementText());
         }
         else if (reader.name() == QLatin1String("S")) {
             pk.S = Bignum::fromDecimalString(reader.readElementText());
         }
         else if (reader.name() == QLatin1String("Bases")) {
             const auto num = reader.attributes().value(QLatin1String("num")).toInt();
             pk.R.reserve(num);
         }
         else if (reader.name().startsWith(QLatin1String("Base_"))) {
             pk.R.push_back(Bignum::fromDecimalString(reader.readElementText()));
         }
     }
 
     return pk;
 }