From 20536cb67ae20b901991d11f2b3750cff86a5236 Mon Sep 17 00:00:00 2001
From: Julien Maffre <jumaffre@microsoft.com>
Date: Fri, 18 Aug 2023 13:17:29 +0000
Subject: [PATCH] Support for OpenSSL 3

---
 doc/index.rst                   |  3 ---
 merklecpp.h                     | 36 ++++-----------------------------
 test/compare_hash_functions.cpp | 21 -------------------
 3 files changed, 4 insertions(+), 56 deletions(-)

diff --git a/doc/index.rst b/doc/index.rst
index c66aaea..80a2ae4 100644
--- a/doc/index.rst
+++ b/doc/index.rst
@@ -55,9 +55,6 @@ To enable these bindings, merklecpp requires the compiler macros
 .. doxygenfunction:: merkle::sha256_compress
    :project: merklecpp
 
-.. doxygenfunction:: merkle::sha256_compress_openssl
-   :project: merklecpp
-
 .. doxygenfunction:: merkle::sha256_openssl
    :project: merklecpp
 
diff --git a/merklecpp.h b/merklecpp.h
index 0505907..2cd0aea 100644
--- a/merklecpp.h
+++ b/merklecpp.h
@@ -17,6 +17,7 @@
 #include <vector>
 
 #ifdef HAVE_OPENSSL
+#  include <openssl/evp.h>
 #  include <openssl/sha.h>
 #endif
 
@@ -1885,34 +1886,6 @@ namespace merkle
   // clang-format on
 
 #ifdef HAVE_OPENSSL
-  /// @brief OpenSSL's SHA256 compression function
-  /// @param l Left node hash
-  /// @param r Right node hash
-  /// @param out Output node hash
-  /// @note Some versions of OpenSSL may not provide SHA256_Transform.
-  static inline void sha256_compress_openssl(
-    const HashT<32>& l, const HashT<32>& r, HashT<32>& out)
-  {
-    unsigned char block[32 * 2];
-    memcpy(&block[0], l.bytes, 32);
-    memcpy(&block[32], r.bytes, 32);
-
-    const EVP_MD* md = EVP_sha256();
-    int rc = EVP_Digest(&block[0], 32 * 2, h, nullptr, md, nullptr);
-    if (rc != 1)
-    {
-      throw std::logic_error(fmt::format("EVP_Digest failed: {}", rc));
-    }
-
-    // SHA256_CTX ctx;
-    // if (SHA256_Init(&ctx) != 1)
-    //   printf("SHA256_Init error");
-    // SHA256_Transform(&ctx, &block[0]);
-
-    for (int i = 0; i < 8; i++)
-      ((uint32_t*)out.bytes)[i] = convert_endianness(((uint32_t*)ctx.h)[i]);
-  }
-
   /// @brief OpenSSL SHA256
   /// @param l Left node hash
   /// @param r Right node hash
@@ -1928,13 +1901,12 @@ namespace merkle
     memcpy(&block[32], r.bytes, 32);
 
     const EVP_MD* md = EVP_sha256();
-    int rc = EVP_Digest(&block[0], sizeof(block), h, nullptr, md, nullptr);
+    int rc =
+      EVP_Digest(&block[0], sizeof(block), out.bytes, nullptr, md, nullptr);
     if (rc != 1)
     {
-      throw std::logic_error(fmt::format("EVP_Digest failed: {}", rc));
+      throw std::runtime_error("EVP_Digest failed: " + std::to_string(rc));
     }
-
-    // SHA256(block, sizeof(block), out.bytes);
   }
 #endif
 
diff --git a/test/compare_hash_functions.cpp b/test/compare_hash_functions.cpp
index 76d48e5..94d80e7 100644
--- a/test/compare_hash_functions.cpp
+++ b/test/compare_hash_functions.cpp
@@ -47,7 +47,6 @@ typedef merkle::TreeT<32, sha256_evercrypt> EverCryptFullTree;
 #endif
 
 #ifdef HAVE_OPENSSL
-typedef merkle::TreeT<32, merkle::sha256_compress_openssl> OpenSSLTree;
 typedef merkle::TreeT<32, merkle::sha256_openssl> OpenSSLFullTree;
 #endif
 
@@ -103,10 +102,6 @@ void compare_compression_hashes()
     EverCryptTree mte;
 #endif
 
-#ifdef HAVE_OPENSSL
-    OpenSSLTree mto;
-#endif
-
 #ifdef HAVE_MBEDTLS
     MbedTLSTree mtm;
 #endif
@@ -123,10 +118,6 @@ void compare_compression_hashes()
       mte.insert(h);
 #endif
 
-#ifdef HAVE_OPENSSL
-      mto.insert(h);
-#endif
-
 #ifdef HAVE_MBEDTLS
       mtm.insert(h);
 #endif
@@ -139,10 +130,6 @@ void compare_compression_hashes()
         compare_roots(mt, mte, "EverCrypt");
 #endif
 
-#ifdef HAVE_OPENSSL
-        compare_roots(mt, mto, "OpenSSL");
-#endif
-
 #ifdef HAVE_MBEDTLS
         compare_roots(mt, mtm, "mbedTLS");
 #endif
@@ -155,10 +142,6 @@ void compare_compression_hashes()
     compare_roots(mt, mte, "EverCrypt");
 #endif
 
-#ifdef HAVE_OPENSSL
-    compare_roots(mt, mto, "OpenSSL");
-#endif
-
 #ifdef HAVE_MBEDTLS
     compare_roots(mt, mtm, "mbedTLS");
 #endif
@@ -329,10 +312,6 @@ int main()
 
     bench<merkle::Tree>(hashes, "merklecpp", root_interval);
 
-#ifdef HAVE_OPENSSL
-    bench<OpenSSLTree>(hashes, "OpenSSL", root_interval);
-#endif
-
 #ifdef HAVE_MBEDTLS
     bench<MbedTLSTree>(hashes, "mbedTLS", root_interval);
 #endif