crypto: require key on ChaCha20 initialization

2 files changed, 4 insertions, 7 deletions

diff --git a/src/crypto/chacha20.cpp b/src/crypto/chacha20.cpp
index 438e451c9a..143179f905 100644
--- a/src/crypto/chacha20.cpp
+++ b/src/crypto/chacha20.cpp
@@ -40,11 +40,6 @@ void ChaCha20Aligned::SetKey(Span<const std::byte> key) noexcept
     input[11] = 0;
 }
 
-ChaCha20Aligned::ChaCha20Aligned() noexcept
-{
-    memset(input, 0, sizeof(input));
-}
-
 ChaCha20Aligned::~ChaCha20Aligned()
 {
     memory_cleanse(input, sizeof(input));
diff --git a/src/crypto/chacha20.h b/src/crypto/chacha20.h
index a766f7d13c..4d16961609 100644
--- a/src/crypto/chacha20.h
+++ b/src/crypto/chacha20.h
@@ -34,7 +34,8 @@ public:
     /** Block size (inputs/outputs to Keystream / Crypt should be multiples of this). */
     static constexpr unsigned BLOCKLEN{64};
 
-    ChaCha20Aligned() noexcept;
+    /** For safety, disallow initialization without key. */
+    ChaCha20Aligned() noexcept = delete;
 
     /** Initialize a cipher with specified 32-byte key. */
     ChaCha20Aligned(Span<const std::byte> key) noexcept;
@@ -84,7 +85,8 @@ public:
     /** Expected key length in constructor and SetKey. */
     static constexpr unsigned KEYLEN = ChaCha20Aligned::KEYLEN;
 
-    ChaCha20() noexcept = default;
+    /** For safety, disallow initialization without key. */
+    ChaCha20() noexcept = delete;
 
     /** Initialize a cipher with specified 32-byte key. */
     ChaCha20(Span<const std::byte> key) noexcept : m_aligned(key) {}