x509: make PrivateKey::getPublicKey() thread-safe

include/opendht/crypto.h

@@ -33,6 +33,7 @@ extern "C" {
 #include <vector>
 #include <memory>
 #include <atomic>
+#include <mutex>
 
 #ifdef _WIN32
 #include <iso646.h>
@@ -207,6 +208,7 @@ private:
     PrivateKey& operator=(const PrivateKey&) = delete;
     Blob decryptBloc(const uint8_t* src, size_t src_size) const;
 
+    mutable std::mutex publicKeyMutex_ {};
     mutable std::shared_ptr<PublicKey> publicKey_ {};
 };
 

src/crypto.cpp

@@ -361,6 +361,7 @@ PrivateKey::getPublicKey() const
 const std::shared_ptr<PublicKey>&
 PrivateKey::getSharedPublicKey() const
 {
+    std::lock_guard<std::mutex> lock(publicKeyMutex_);
     if (not publicKey_) {
         auto pk = std::make_shared<PublicKey>();
         if (auto err = gnutls_pubkey_import_privkey(pk->pk, key, GNUTLS_KEY_KEY_CERT_SIGN | GNUTLS_KEY_CRL_SIGN, 0))