[pki] check for NULL and small cosmetic changes

src/pki.c

@@ -56,11 +56,11 @@ void ssh_key_clean (ssh_key key){
     if(key == NULL)
         return;
 #ifdef HAVE_LIBGCRYPT
-  gcry_sexp_release(key->dsa);
-  gcry_sexp_release(key->rsa);
+    if(key->dsa) gcry_sexp_release(key->dsa);
+    if(key->rsa) gcry_sexp_release(key->rsa);
 #elif defined HAVE_LIBCRYPTO
-  DSA_free(key->dsa);
-  RSA_free(key->rsa);
+    if(key->dsa) DSA_free(key->dsa);
+    if(key->rsa) RSA_free(key->rsa);
 #endif
     key->flags=SSH_KEY_FLAG_EMPTY;
     key->type=SSH_KEYTYPE_UNKNOWN;
@@ -85,8 +85,9 @@ void ssh_key_free (ssh_key key){
  * @returns SSH_KEYTYPE_UNKNOWN if the type is unknown
  */
 enum ssh_keytypes_e ssh_key_type(ssh_key key){
-  if (key==NULL)
+    if (key == NULL) {
         return SSH_KEYTYPE_UNKNOWN;
+    }
     return key->type;
 }