image_verify: Add support for OpenSSL 1.1.0
With OpenSSL 1.1.0, some of the functions were renamed, for
example EVP_MD_CTX_create() and EVP_MD_CTX_destroy() were
renamed to EVP_MD_CTX_new() and EVP_MD_CTX_free().
Reference: https://wiki.openssl.org/index.php/OpenSSL_1.1.0_Changes
Abstract them to support old and new APIs.
Resolves openbmc/openbmc#3137
Tested: Verified the signature verification was successful.
Change-Id: If8b3f185666c3db59567c4ee3bdfa168c501d3da
Signed-off-by: Adriana Kobylak <anoo@us.ibm.com>
diff --git a/utils.hpp b/utils.hpp
new file mode 100644
index 0000000..90569bf
--- /dev/null
+++ b/utils.hpp
@@ -0,0 +1,15 @@
+#pragma once
+
+// With OpenSSL 1.1.0, some functions were deprecated. Need to abstract them
+// to make the code backward compatible with older OpenSSL veresions.
+// Reference: https://wiki.openssl.org/index.php/OpenSSL_1.1.0_Changes
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
+
+#include <openssl/evp.h>
+
+extern "C" {
+EVP_MD_CTX* EVP_MD_CTX_new(void);
+void EVP_MD_CTX_free(EVP_MD_CTX* ctx);
+}
+
+#endif // OPENSSL_VERSION_NUMBER < 0x10100000L