Added acl_setrole function. The function enables/disables role privileges to

the current user via the current security_context

sql/sql_acl.cc

@@ -1672,6 +1672,67 @@ bool acl_getroot(Security_context *sctx, char *user, char *host,
   DBUG_RETURN(res);
 }
 
+bool acl_setrole(THD *thd, char *rolename)
+{
+  bool is_granted;
+  int result= 0;
+
+  /* clear role privileges */
+  mysql_mutex_lock(&acl_cache->lock);
+
+  ACL_USER *role= find_acl_role(rolename);
+  ACL_USER *acl_user;
+
+  if (!strcasecmp(rolename, "NONE")) {
+    /* have to clear the privileges */
+    /* get the current user */
+    acl_user= find_acl_user(thd->security_ctx->host, thd->security_ctx->user,
+                             FALSE);
+    if (acl_user == NULL)
+      result= -1;
+    else
+      thd->security_ctx->master_access= acl_user->access;
+
+    goto end;
+  }
+
+  if (role == NULL) {
+    result= -1;
+    goto end;
+  }
+
+  for (uint i=0 ; i < role->role_grants.elements ; i++)
+  {
+    acl_user= *(dynamic_element(&role->role_grants, i, ACL_USER**));
+    if ((!acl_user->user.str && !thd->security_ctx->user[0]) ||
+        (acl_user->user.str && !strcmp(thd->security_ctx->user,
+                                       acl_user->user.str)))
+    {
+      if (compare_hostname(&acl_user->host, thd->security_ctx->host,
+                                            thd->security_ctx->host))
+      {
+        is_granted= TRUE;
+        break;
+      }
+    }
+  }
+
+  if (!is_granted)
+  {
+    result= 1;
+    goto end;
+  }
+
+  /* merge the privileges */
+  thd->security_ctx->master_access= acl_user->access | role->access;
+  /* mark the current role */
+  strcpy(thd->security_ctx->priv_role, rolename);
+
+end:
+  mysql_mutex_unlock(&acl_cache->lock);
+  return result;
+}
+
 static uchar* check_get_key(ACL_USER *buff, size_t *length,
                             my_bool not_used __attribute__((unused)))
 {

sql/sql_acl.h

@@ -382,4 +382,5 @@ get_cached_table_access(GRANT_INTERNAL_INFO *grant_internal_info,
 
 bool acl_check_proxy_grant_access (THD *thd, const char *host, const char *user,
                                    bool with_grant);
+bool acl_setrole(THD *thd, char *rolename);
 #endif /* SQL_ACL_INCLUDED */

sql/sql_class.cc

@@ -3647,7 +3647,7 @@ void Security_context::init()
 {
   host= user= ip= external_user= 0;
   host_or_ip= "connecting host";
-  priv_user[0]= priv_host[0]= proxy_user[0]= '\0';
+  priv_user[0]= priv_host[0]= proxy_user[0]= priv_role[0]= '\0';
   master_access= 0;
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
   db_access= NO_ACCESS;

sql/sql_class.h

@@ -1041,6 +1041,8 @@ class Security_context {
   char   proxy_user[USERNAME_LENGTH + MAX_HOSTNAME + 5];
   /* The host privilege we are using */
   char   priv_host[MAX_HOSTNAME];
+  /* The role privilege we are using */
+  char   priv_role[USERNAME_LENGTH];
   /* The external user (if available) */
   char   *external_user;
   /* points to host if host is available, otherwise points to ip */