Implementation of put state function

Author: MatheusNtg

Makefile

@@ -1,4 +1,4 @@
-ccflags-y += -D_LUNATIK -D_KERNEL -I$(src) -D_CONFIG_FULL_PANIC -DLUNATIK_UNUSED \
+ccflags-y += -D_LUNATIK -D_KERNEL -I$(src) -D_CONFIG_FULL_PANIC -DLUNATIK_UNUSED -DDEBUG\
 	-I$(src)/lua -I$(src)/deps/lua-memory/src
 asflags-y += -D_LUNATIK -D_KERNEL
 

lib/lunatik.c

@@ -546,6 +546,9 @@ static int response_state_handler(struct nl_msg *msg, void *arg)
 	} else if (attrs_tb[OP_ERROR] && nla_get_u8(attrs_tb[OP_ERROR])) {
 		state->cb_result = CB_ERROR;
 		return NL_OK;
+	} else if (attrs_tb[NOT_IN_USE] && nla_get_u8(attrs_tb[NOT_IN_USE])) {
+		state->cb_result = CB_ERROR;
+		return NL_OK;
 	}
 
 	if (attrs_tb[CURR_ALLOC]) {
@@ -810,3 +813,24 @@ int lunatik_getcurralloc(struct lunatik_nl_state *state)
 	printf("Failed to put attribute to get current alloc of state %s\n", state->name);
 	return -1;
 }
+
+int lunatik_putstate(struct lunatik_nl_state *state)
+{
+	struct nl_msg *msg;
+	
+	int err = -1;
+
+	if ((msg = prepare_message(PUT_STATE, 0)) == NULL) 
+		return err;
+
+	NLA_PUT_STRING(msg, STATE_NAME, state->name);
+
+	if ((err = nl_send_auto(state->control_sock, msg)) < 0)
+		return err;	
+
+	return receive_state_op_result(state);
+
+nla_put_failure:
+	printf("Failed to put attribute to put state\n");
+	return -1;
+}

lib/lunatik.h

@@ -113,4 +113,6 @@ int lunatik_datasend(struct lunatik_nl_state *state,
 
 int lunatik_getcurralloc(struct lunatik_nl_state *state);
 
+int lunatik_putstate(struct lunatik_nl_state *state);
+
 #endif /* LUNATIK_H */

lib/lunatik_module.c

@@ -158,7 +158,7 @@ static int lstate_close(lua_State *L)
 		lua_pushnil(L);
 		return 1;
 	}
-
+	free(state);
 	lua_pushboolean(L, true);
 	return 1;
 }
@@ -319,6 +319,21 @@ static int lstate_getcurralloc(lua_State *L)
 	return 1;
 }
 
+static int lstate_put(lua_State *L)
+{
+	struct lunatik_nl_state *state = getnlstate(L);
+
+	if (lunatik_putstate(state)) {
+		lua_pushnil(L);
+		return 1;
+	}
+	
+	free(state);
+	lua_pushboolean(L, true);
+
+	return 1;
+}
+
 static const luaL_Reg session_mt[] = {
 	{"close", lsession_close},
 	{"getfd", lsession_getfd},
@@ -337,6 +352,7 @@ static const luaL_Reg state_mt[] = {
 	{"close", lstate_close},
 	{"send", lstate_datasend},
 	{"receive", lstate_datareceive},
+	{"put", lstate_put},
 	{NULL, NULL}
 };
 

netlink.c

@@ -51,6 +51,7 @@ static int lunatikN_data(struct sk_buff *buff, struct genl_info *info);
 static int lunatikN_datainit(struct sk_buff *buff, struct genl_info *info);
 static int lunatikN_sendstate(struct sk_buff *buff, struct genl_info *info);
 static int lunatikN_getcurralloc(struct sk_buff *buff, struct genl_info *info);
+static int lunatikN_putstate(struct sk_buff *buff, struct genl_info *info);
 
 struct nla_policy lunatik_policy[ATTRS_COUNT] = {
 	[STATE_NAME]  = { .type = NLA_STRING },
@@ -123,8 +124,16 @@ static const struct genl_ops l_ops[] = {
 		.doit   = lunatikN_getcurralloc,
 #if LINUX_VERSION_CODE < KERNEL_VERSION(5,2,0)
 		.policy = lunatik_policy
+#endif
+	},
+	{
+		.cmd    = PUT_STATE,
+		.doit   = lunatikN_putstate,
+#if LINUX_VERSION_CODE < KERNEL_VERSION(5,2,0)
+		.policy = lunatik_policy
 #endif
 	}
+
 };
 
 struct genl_family lunatik_family = {
@@ -714,6 +723,34 @@ static int lunatikN_getcurralloc(struct sk_buff *buff, struct genl_info *info)
 	return 0;
 }
 
+static int lunatikN_putstate(struct sk_buff *buff, struct genl_info *info)
+{
+	struct lunatik_state *s;
+	char *state_name;
+
+	pr_debug("Received a PUT_STATE command\n");
+
+	state_name = (char*)nla_data(info->attrs[STATE_NAME]);
+	s = lunatik_netstatelookup(state_name, genl_info_net(info));
+
+	if (s == NULL)
+		goto error;
+
+	if (!s->inuse) {
+		reply_with(NOT_IN_USE, PUT_STATE, info);
+		return 0;
+	}
+
+	s->inuse = false;
+	reply_with(OP_SUCESS, PUT_STATE, info);	
+
+	return 0;
+
+error:
+	reply_with(OP_ERROR, PUT_STATE, info);
+	return 0;
+}
+
 /* Note: Most of the function below is copied from NFLua: https://github.com/cujoai/nflua
  * Copyright (C) 2017-2019  CUJO LLC
  *

netlink_common.h

@@ -44,6 +44,7 @@ enum lunatik_operations {
 	DATA_INIT,
 	GET_STATE,
 	GET_CURRALLOC,
+	PUT_STATE,
 };
 
 enum lunatik_attrs {
@@ -63,6 +64,7 @@ enum lunatik_attrs {
 	LUNATIK_DATA_LEN,
 	CURR_ALLOC,
 	STATE_NOT_FOUND,
+	NOT_IN_USE,
 	ATTRS_COUNT
 #define ATTRS_MAX	(ATTRS_COUNT - 1)
 };