Fix QCH:supportsAlgorithm() result for unsupported hashes in OpenSSL

OpenSSL doesn't support some Blake2s and Blake2b hashes and querying
these would automatically report that they are unsupported, while we are
actually using non-OpenSSL implementataion for these and therefore they
are always supported.

Change-Id: I300694459891c3103502705d6c8271caa47d8d01
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
(cherry picked from commit 86a517ac786c90b9ce8deb502c413287e31058c2)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 21 insertions, 1 deletions

diff --git a/src/corelib/tools/qcryptographichash.cpp b/src/corelib/tools/qcryptographichash.cpp
index 3258011323..6c71e095dc 100644
--- a/src/corelib/tools/qcryptographichash.cpp
+++ b/src/corelib/tools/qcryptographichash.cpp
@@ -222,7 +222,21 @@ static constexpr const char * methodToName(QCryptographicHash::Algorithm method)
     default: return nullptr;
     }
 }
-#endif
+
+/*
+    Checks whether given method is not provided by OpenSSL and whether we will
+    have a fallback to non-OpenSSL implementation.
+*/
+static constexpr bool useNonOpenSSLFallback(QCryptographicHash::Algorithm method) noexcept
+{
+    if (method == QCryptographicHash::Blake2b_160 || method == QCryptographicHash::Blake2b_256 ||
+        method == QCryptographicHash::Blake2b_384 || method == QCryptographicHash::Blake2s_128 ||
+        method == QCryptographicHash::Blake2s_160 || method == QCryptographicHash::Blake2s_224)
+        return true;
+
+    return false;
+}
+#endif // USING_OPENSSL30
 
 class QCryptographicHashPrivate
 {
@@ -913,6 +927,12 @@ bool QCryptographicHash::supportsAlgorithm(QCryptographicHash::Algorithm method)
 bool QCryptographicHashPrivate::supportsAlgorithm(QCryptographicHash::Algorithm method)
 {
 #ifdef USING_OPENSSL30
+    // OpenSSL doesn't support Blake2b{60,236,384} and Blake2s{128,160,224}
+    // and these would automatically return FALSE in that case, while they are
+    // actually supported by our non-OpenSSL implementation.
+    if (useNonOpenSSLFallback(method))
+        return true;
+
     OSSL_PROVIDER_load(nullptr, "legacy");
     OSSL_PROVIDER_load(nullptr, "default");