1 files changed, 12 insertions, 3 deletions

diff --git a/src/lib/libcrypto/evp/digest.c b/src/lib/libcrypto/evp/digest.c
index b22eed4421..0623ddf1f0 100644
--- a/src/lib/libcrypto/evp/digest.c
+++ b/src/lib/libcrypto/evp/digest.c
@@ -248,6 +248,7 @@ int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in)
 
 int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in)
         {
+        unsigned char *tmp_buf;
         if ((in == NULL) || (in->digest == NULL))
                 {
                 EVPerr(EVP_F_EVP_MD_CTX_COPY,EVP_R_INPUT_NOT_INITIALIZED);
@@ -262,15 +263,22 @@ int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in)
                 }
 #endif
 
+        if (out->digest == in->digest)
+                {
+                tmp_buf = out->md_data;
+                EVP_MD_CTX_set_flags(out,EVP_MD_CTX_FLAG_REUSE);
+                }
+        else tmp_buf = NULL;
         EVP_MD_CTX_cleanup(out);
         memcpy(out,in,sizeof *out);
 
         if (out->digest->ctx_size)
                 {
-                out->md_data=OPENSSL_malloc(out->digest->ctx_size);
+                if (tmp_buf) out->md_data = tmp_buf;
+                else out->md_data=OPENSSL_malloc(out->digest->ctx_size);
                 memcpy(out->md_data,in->md_data,out->digest->ctx_size);
                 }
-        
+
         if (out->digest->copy)
                 return out->digest->copy(out,in);
         
@@ -308,7 +316,8 @@ int EVP_MD_CTX_cleanup(EVP_MD_CTX *ctx)
         if (ctx->digest && ctx->digest->cleanup
             && !EVP_MD_CTX_test_flags(ctx,EVP_MD_CTX_FLAG_CLEANED))
                 ctx->digest->cleanup(ctx);
-        if (ctx->digest && ctx->digest->ctx_size && ctx->md_data)
+        if (ctx->digest && ctx->digest->ctx_size && ctx->md_data
+            && !EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_REUSE))
                 {
                 OPENSSL_cleanse(ctx->md_data,ctx->digest->ctx_size);
                 OPENSSL_free(ctx->md_data);