From f3e208572f8c3aa16d7a220f8b3671c6c4fa8e8c Mon Sep 17 00:00:00 2001
From: Simon Rozman <simon@rozman.si>
Date: Tue, 25 Feb 2020 12:45:22 +0100
Subject: [PATCH] Add SHA-256 support

Signed-off-by: Simon Rozman <simon@rozman.si>
---
 include/wxex/crypto.h | 29 +++++++++++++++++++
 src/crypto.cpp        | 67 +++++++++++++++++++++++++++----------------
 2 files changed, 71 insertions(+), 25 deletions(-)

diff --git a/include/wxex/crypto.h b/include/wxex/crypto.h
index 316d511..65e4a46 100644
--- a/include/wxex/crypto.h
+++ b/include/wxex/crypto.h
@@ -270,6 +270,35 @@ public:
 };
 
 
+#if (NTDDI_VERSION > NTDDI_WINXPSP2)
+
+///
+/// SHA-256 Cryptographics Hash
+///
+class WXEXTEND_API wxCryptoHashSHA256 : public wxCryptoHash
+{
+public:
+    ///
+    /// Creates a new cryptographics SHA-256 hash
+    ///
+    wxCryptoHashSHA256(wxCryptoSession &session);
+
+
+    ///
+    /// Finish hashing and return hash data.
+    ///
+    /// \param[out] hash  Hash data
+    ///
+    /// \returns
+    /// - \c true if succeeded
+    /// - \c false otherwise
+    ///
+    virtual _Success_(return != 0) bool GetValue(_Out_ wxMemoryBuffer &hash);
+};
+
+#endif
+
+
 ///
 /// Cryptographics Key Base
 ///
diff --git a/src/crypto.cpp b/src/crypto.cpp
index 321de9d..d61148d 100644
--- a/src/crypto.cpp
+++ b/src/crypto.cpp
@@ -22,6 +22,23 @@
 #pragma comment(lib, "Crypt32.lib")
 
 
+static bool wxGetHashValue(HCRYPTHASH h, DWORD length, wxMemoryBuffer &hash)
+{
+    // Prepare buffer.
+    hash.SetBufSize(length);
+
+    // Query hash value.
+    if (::CryptGetHashParam(h, HP_HASHVAL, (BYTE*)hash.GetData(), &length, 0)) {
+        hash.SetDataLen(length);
+        return true;
+    } else
+        wxLogLastError(wxT("CryptGetHashParam(HP_HASHVAL)"));
+
+    hash.Clear();
+    return false;
+}
+
+
 //////////////////////////////////////////////////////////////////////////
 // wxCryptoSession
 //////////////////////////////////////////////////////////////////////////
@@ -89,17 +106,7 @@ bool wxCryptoHash::GetValue(wxMemoryBuffer &hash)
     DWORD size, length = sizeof(size);
     if (::CryptGetHashParam(m_h, HP_HASHSIZE, (BYTE*)&size, &length, 0)) {
         wxASSERT(length == sizeof(size));
-
-        // Prepare buffer.
-        length = size;
-        hash.SetBufSize(length);
-
-        // Query hash value.
-        if (::CryptGetHashParam(m_h, HP_HASHVAL, (BYTE*)hash.GetData(), &length, 0)) {
-            hash.SetDataLen(length);
-            return true;
-        } else
-            wxLogLastError(wxT("CryptGetHashParam(HP_HASHVAL)"));
+        return wxGetHashValue(m_h, size, hash);
     } else
         wxLogLastError(wxT("CryptGetHashParam(HP_HASHSIZE)"));
 
@@ -153,23 +160,33 @@ _Use_decl_annotations_
 bool wxCryptoHashSHA1::GetValue(wxMemoryBuffer &hash)
 {
     wxASSERT_MSG(m_h, wxT("object uninitialized"));
-
-    // Prepare buffer.
-    DWORD length = 20;
-    hash.SetBufSize(length);
-
-    // Query hash value.
-    if (::CryptGetHashParam(m_h, HP_HASHVAL, (BYTE*)hash.GetData(), &length, 0)) {
-        hash.SetDataLen(length);
-        return true;
-    } else
-        wxLogLastError(wxT("CryptGetHashParam(HP_HASHVAL)"));
-
-    hash.Clear();
-    return false;
+    return wxGetHashValue(m_h, 20, hash);
 }
 
 
+#if (NTDDI_VERSION > NTDDI_WINXPSP2)
+
+//////////////////////////////////////////////////////////////////////////
+// wxCryptoHashSHA256
+//////////////////////////////////////////////////////////////////////////
+
+wxCryptoHashSHA256::wxCryptoHashSHA256(wxCryptoSession &session)
+{
+    if (!::CryptCreateHash(session, CALG_SHA_256, 0, 0, &m_h))
+        wxLogLastError(wxT("CryptCreateHash(CALG_SHA_256)"));
+}
+
+
+_Use_decl_annotations_
+bool wxCryptoHashSHA256::GetValue(wxMemoryBuffer &hash)
+{
+    wxASSERT_MSG(m_h, wxT("object uninitialized"));
+    return wxGetHashValue(m_h, 32, hash);
+}
+
+#endif
+
+
 //////////////////////////////////////////////////////////////////////////
 // wxCryptoKey
 //////////////////////////////////////////////////////////////////////////