wrapper: move EVP_CIPHER_CTX_free call to libcrypto.c

With this change, a HAVE_LIBCRYPTO #ifdef is removed from wrapper.c.
Now, the libcrypto-specific logic for EVP_CIPHER_CTX_free is moved
into the ssh_cipher_struct cleanup callback handler for those
ciphers.

Signed-off-by: Jon Simons <jon@jonsimons.org>
Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

src/libcrypto.c

@@ -554,6 +554,9 @@ static void evp_cipher_decrypt(struct ssh_cipher_struct *cipher,
 
 static void evp_cipher_cleanup(struct ssh_cipher_struct *cipher) {
     EVP_CIPHER_CTX_cleanup(cipher->ctx);
+    if (cipher->ctx != NULL) {
+        EVP_CIPHER_CTX_free(cipher->ctx);
+    }
 }
 
 #ifndef HAVE_OPENSSL_EVP_AES_CTR

src/wrapper.c

@@ -124,12 +124,6 @@ void ssh_cipher_clear(struct ssh_cipher_struct *cipher){
     if (cipher->cleanup != NULL) {
         cipher->cleanup(cipher);
     }
-
-#ifdef HAVE_LIBCRYPTO
-    if (cipher->ctx != NULL) {
-        EVP_CIPHER_CTX_free(cipher->ctx);
-    }
-#endif
 }
 
 static void cipher_free(struct ssh_cipher_struct *cipher) {