net/802/garp.c

Source file repositories/reference/linux-study-clean/net/802/garp.c

File Facts

System
Linux kernel
Corpus path
net/802/garp.c
Extension
.c
Size
18382 bytes
Lines
654
Domain
Networking Core
Bucket
Sockets, Protocols, Packet Path, And Network Policy
Inferred role
Networking Core: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 *	IEEE 802.1D Generic Attribute Registration Protocol (GARP)
 *
 *	Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
 */
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/llc.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <net/llc.h>
#include <net/llc_pdu.h>
#include <net/garp.h>
#include <linux/unaligned.h>

static unsigned int garp_join_time __read_mostly = 200;
module_param(garp_join_time, uint, 0644);
MODULE_PARM_DESC(garp_join_time, "Join time in ms (default 200ms)");
MODULE_DESCRIPTION("IEEE 802.1D Generic Attribute Registration Protocol (GARP)");
MODULE_LICENSE("GPL");

static const struct garp_state_trans {
	u8	state;
	u8	action;
} garp_applicant_state_table[GARP_APPLICANT_MAX + 1][GARP_EVENT_MAX + 1] = {
	[GARP_APPLICANT_VA] = {
		[GARP_EVENT_TRANSMIT_PDU]	= { .state = GARP_APPLICANT_AA,
						    .action = GARP_ACTION_S_JOIN_IN },
		[GARP_EVENT_R_JOIN_IN]		= { .state = GARP_APPLICANT_AA },
		[GARP_EVENT_R_JOIN_EMPTY]	= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_R_EMPTY]		= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_R_LEAVE_IN]		= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_R_LEAVE_EMPTY]	= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_REQ_JOIN]		= { .state = GARP_APPLICANT_INVALID },
		[GARP_EVENT_REQ_LEAVE]		= { .state = GARP_APPLICANT_LA },
	},
	[GARP_APPLICANT_AA] = {
		[GARP_EVENT_TRANSMIT_PDU]	= { .state = GARP_APPLICANT_QA,
						    .action = GARP_ACTION_S_JOIN_IN },
		[GARP_EVENT_R_JOIN_IN]		= { .state = GARP_APPLICANT_QA },
		[GARP_EVENT_R_JOIN_EMPTY]	= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_R_EMPTY]		= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_R_LEAVE_IN]		= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_R_LEAVE_EMPTY]	= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_REQ_JOIN]		= { .state = GARP_APPLICANT_INVALID },
		[GARP_EVENT_REQ_LEAVE]		= { .state = GARP_APPLICANT_LA },
	},
	[GARP_APPLICANT_QA] = {
		[GARP_EVENT_TRANSMIT_PDU]	= { .state = GARP_APPLICANT_INVALID },
		[GARP_EVENT_R_JOIN_IN]		= { .state = GARP_APPLICANT_QA },
		[GARP_EVENT_R_JOIN_EMPTY]	= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_R_EMPTY]		= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_R_LEAVE_IN]		= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_R_LEAVE_EMPTY]	= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_REQ_JOIN]		= { .state = GARP_APPLICANT_INVALID },
		[GARP_EVENT_REQ_LEAVE]		= { .state = GARP_APPLICANT_LA },
	},
	[GARP_APPLICANT_LA] = {
		[GARP_EVENT_TRANSMIT_PDU]	= { .state = GARP_APPLICANT_VO,
						    .action = GARP_ACTION_S_LEAVE_EMPTY },
		[GARP_EVENT_R_JOIN_IN]		= { .state = GARP_APPLICANT_LA },
		[GARP_EVENT_R_JOIN_EMPTY]	= { .state = GARP_APPLICANT_VO },
		[GARP_EVENT_R_EMPTY]		= { .state = GARP_APPLICANT_LA },
		[GARP_EVENT_R_LEAVE_IN]		= { .state = GARP_APPLICANT_LA },
		[GARP_EVENT_R_LEAVE_EMPTY]	= { .state = GARP_APPLICANT_VO },
		[GARP_EVENT_REQ_JOIN]		= { .state = GARP_APPLICANT_VA },
		[GARP_EVENT_REQ_LEAVE]		= { .state = GARP_APPLICANT_INVALID },
	},
	[GARP_APPLICANT_VP] = {
		[GARP_EVENT_TRANSMIT_PDU]	= { .state = GARP_APPLICANT_AA,
						    .action = GARP_ACTION_S_JOIN_IN },
		[GARP_EVENT_R_JOIN_IN]		= { .state = GARP_APPLICANT_AP },
		[GARP_EVENT_R_JOIN_EMPTY]	= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_R_EMPTY]		= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_R_LEAVE_IN]		= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_R_LEAVE_EMPTY]	= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_REQ_JOIN]		= { .state = GARP_APPLICANT_INVALID },
		[GARP_EVENT_REQ_LEAVE]		= { .state = GARP_APPLICANT_VO },
	},
	[GARP_APPLICANT_AP] = {
		[GARP_EVENT_TRANSMIT_PDU]	= { .state = GARP_APPLICANT_QA,
						    .action = GARP_ACTION_S_JOIN_IN },
		[GARP_EVENT_R_JOIN_IN]		= { .state = GARP_APPLICANT_QP },
		[GARP_EVENT_R_JOIN_EMPTY]	= { .state = GARP_APPLICANT_VP },
		[GARP_EVENT_R_EMPTY]		= { .state = GARP_APPLICANT_VP },

Annotation

Implementation Notes