free up gost ciphers

Reviewed-by: NViktor Dukhovni <viktor@openssl.org>

engines/ccgost/gost_crypt.c

@@ -109,6 +109,14 @@ const EVP_CIPHER *cipher_gost_cpacnt(void)
     return _hidden_gost89_cnt;
 }
 
+void cipher_gost_destroy(void)
+{
+    EVP_CIPHER_meth_free(_hidden_Gost28147_89_cipher);
+    _hidden_Gost28147_89_cipher = NULL;
+    EVP_CIPHER_meth_free(_hidden_gost89_cnt);
+    _hidden_gost89_cnt = NULL;
+}
+
 /* Implementation of GOST 28147-89 in MAC (imitovstavka) mode */
 /* Init functions which set specific parameters */
 static int gost_imit_init_cpa(EVP_MD_CTX *ctx);

engines/ccgost/gost_eng.c

@@ -77,6 +77,7 @@ static int gost_engine_finish(ENGINE *e)
 static int gost_engine_destroy(ENGINE *e)
 {
     digest_gost_destroy();
+    cipher_gost_destroy();
     imit_gost_cpa_destroy();
 
     gost_param_free();

engines/ccgost/gost_lcl.h

@@ -145,6 +145,7 @@ struct ossl_gost_digest_ctx {
 /* EVP_MD structure for GOST R 34.11 */
 EVP_MD *digest_gost(void);
 void digest_gost_destroy(void);
+void cipher_gost_destroy(void);
 /* EVP_MD structure for GOST 28147 in MAC mode */
 const EVP_MD *imit_gost_cpa(void);
 void imit_gost_cpa_destroy(void);