diff options
Diffstat (limited to '')
| -rw-r--r-- | net/802/garp.c | 649 |
1 files changed, 649 insertions, 0 deletions
diff --git a/net/802/garp.c b/net/802/garp.c new file mode 100644 index 000000000..f6012f8e5 --- /dev/null +++ b/net/802/garp.c @@ -0,0 +1,649 @@ +// 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 <asm/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_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 }, + [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_AO }, + }, + [GARP_APPLICANT_QP] = { + [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, + [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 }, + [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_QO }, + }, + [GARP_APPLICANT_VO] = { + [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, + [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_AO }, + [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_VP }, + [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID }, + }, + [GARP_APPLICANT_AO] = { + [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, + [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO }, + [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_AP }, + [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID }, + }, + [GARP_APPLICANT_QO] = { + [GARP_EVENT_TRANSMIT_PDU] = { .state = GARP_APPLICANT_INVALID }, + [GARP_EVENT_R_JOIN_IN] = { .state = GARP_APPLICANT_QO }, + [GARP_EVENT_R_JOIN_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_LEAVE_IN] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_R_LEAVE_EMPTY] = { .state = GARP_APPLICANT_VO }, + [GARP_EVENT_REQ_JOIN] = { .state = GARP_APPLICANT_QP }, + [GARP_EVENT_REQ_LEAVE] = { .state = GARP_APPLICANT_INVALID }, + }, +}; + +static int garp_attr_cmp(const struct garp_attr *attr, + const void *data, u8 len, u8 type) +{ + if (attr->type != type) + return attr->type - type; + if (attr->dlen != len) + return attr->dlen - len; + return memcmp(attr->data, data, len); +} + +static struct garp_attr *garp_attr_lookup(const struct garp_applicant *app, + const void *data, u8 len, u8 type) +{ + struct rb_node *parent = app->gid.rb_node; + struct garp_attr *attr; + int d; + + while (parent) { + attr = rb_entry(parent, struct garp_attr, node); + d = garp_attr_cmp(attr, data, len, type); + if (d > 0) + parent = parent->rb_left; + else if (d < 0) + parent = parent->rb_right; + else + return attr; + } + return NULL; +} + +static struct garp_attr *garp_attr_create(struct garp_applicant *app, + const void *data, u8 len, u8 type) +{ + struct rb_node *parent = NULL, **p = &app->gid.rb_node; + struct garp_attr *attr; + int d; + + while (*p) { + parent = *p; + attr = rb_entry(parent, struct garp_attr, node); + d = garp_attr_cmp(attr, data, len, type); + if (d > 0) + p = &parent->rb_left; + else if (d < 0) + p = &parent->rb_right; + else { + /* The attribute already exists; re-use it. */ + return attr; + } + } + attr = kmalloc(sizeof(*attr) + len, GFP_ATOMIC); + if (!attr) + return attr; + attr->state = GARP_APPLICANT_VO; + attr->type = type; + attr->dlen = len; + memcpy(attr->data, data, len); + + rb_link_node(&attr->node, parent, p); + rb_insert_color(&attr->node, &app->gid); + return attr; +} + +static void garp_attr_destroy(struct garp_applicant *app, struct garp_attr *attr) +{ + rb_erase(&attr->node, &app->gid); + kfree(attr); +} + +static void garp_attr_destroy_all(struct garp_applicant *app) +{ + struct rb_node *node, *next; + struct garp_attr *attr; + + for (node = rb_first(&app->gid); + next = node ? rb_next(node) : NULL, node != NULL; + node = next) { + attr = rb_entry(node, struct garp_attr, node); + garp_attr_destroy(app, attr); + } +} + +static int garp_pdu_init(struct garp_applicant *app) +{ + struct sk_buff *skb; + struct garp_pdu_hdr *gp; + +#define LLC_RESERVE sizeof(struct llc_pdu_un) + skb = alloc_skb(app->dev->mtu + LL_RESERVED_SPACE(app->dev), + GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + skb->dev = app->dev; + skb->protocol = htons(ETH_P_802_2); + skb_reserve(skb, LL_RESERVED_SPACE(app->dev) + LLC_RESERVE); + + gp = __skb_put(skb, sizeof(*gp)); + put_unaligned(htons(GARP_PROTOCOL_ID), &gp->protocol); + + app->pdu = skb; + return 0; +} + +static int garp_pdu_append_end_mark(struct garp_applicant *app) +{ + if (skb_tailroom(app->pdu) < sizeof(u8)) + return -1; + __skb_put_u8(app->pdu, GARP_END_MARK); + return 0; +} + +static void garp_pdu_queue(struct garp_applicant *app) +{ + if (!app->pdu) + return; + + garp_pdu_append_end_mark(app); + garp_pdu_append_end_mark(app); + + llc_pdu_header_init(app->pdu, LLC_PDU_TYPE_U, LLC_SAP_BSPAN, + LLC_SAP_BSPAN, LLC_PDU_CMD); + llc_pdu_init_as_ui_cmd(app->pdu); + llc_mac_hdr_init(app->pdu, app->dev->dev_addr, + app->app->proto.group_address); + + skb_queue_tail(&app->queue, app->pdu); + app->pdu = NULL; +} + +static void garp_queue_xmit(struct garp_applicant *app) +{ + struct sk_buff *skb; + + while ((skb = skb_dequeue(&app->queue))) + dev_queue_xmit(skb); +} + +static int garp_pdu_append_msg(struct garp_applicant *app, u8 attrtype) +{ + struct garp_msg_hdr *gm; + + if (skb_tailroom(app->pdu) < sizeof(*gm)) + return -1; + gm = __skb_put(app->pdu, sizeof(*gm)); + gm->attrtype = attrtype; + garp_cb(app->pdu)->cur_type = attrtype; + return 0; +} + +static int garp_pdu_append_attr(struct garp_applicant *app, + const struct garp_attr *attr, + enum garp_attr_event event) +{ + struct garp_attr_hdr *ga; + unsigned int len; + int err; +again: + if (!app->pdu) { + err = garp_pdu_init(app); + if (err < 0) + return err; + } + + if (garp_cb(app->pdu)->cur_type != attr->type) { + if (garp_cb(app->pdu)->cur_type && + garp_pdu_append_end_mark(app) < 0) + goto queue; + if (garp_pdu_append_msg(app, attr->type) < 0) + goto queue; + } + + len = sizeof(*ga) + attr->dlen; + if (skb_tailroom(app->pdu) < len) + goto queue; + ga = __skb_put(app->pdu, len); + ga->len = len; + ga->event = event; + memcpy(ga->data, attr->data, attr->dlen); + return 0; + +queue: + garp_pdu_queue(app); + goto again; +} + +static void garp_attr_event(struct garp_applicant *app, + struct garp_attr *attr, enum garp_event event) +{ + enum garp_applicant_state state; + + state = garp_applicant_state_table[attr->state][event].state; + if (state == GARP_APPLICANT_INVALID) + return; + + switch (garp_applicant_state_table[attr->state][event].action) { + case GARP_ACTION_NONE: + break; + case GARP_ACTION_S_JOIN_IN: + /* When appending the attribute fails, don't update state in + * order to retry on next TRANSMIT_PDU event. */ + if (garp_pdu_append_attr(app, attr, GARP_JOIN_IN) < 0) + return; + break; + case GARP_ACTION_S_LEAVE_EMPTY: + garp_pdu_append_attr(app, attr, GARP_LEAVE_EMPTY); + /* As a pure applicant, sending a leave message implies that + * the attribute was unregistered and can be destroyed. */ + garp_attr_destroy(app, attr); + return; + default: + WARN_ON(1); + } + + attr->state = state; +} + +int garp_request_join(const struct net_device *dev, + const struct garp_application *appl, + const void *data, u8 len, u8 type) +{ + struct garp_port *port = rtnl_dereference(dev->garp_port); + struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]); + struct garp_attr *attr; + + spin_lock_bh(&app->lock); + attr = garp_attr_create(app, data, len, type); + if (!attr) { + spin_unlock_bh(&app->lock); + return -ENOMEM; + } + garp_attr_event(app, attr, GARP_EVENT_REQ_JOIN); + spin_unlock_bh(&app->lock); + return 0; +} +EXPORT_SYMBOL_GPL(garp_request_join); + +void garp_request_leave(const struct net_device *dev, + const struct garp_application *appl, + const void *data, u8 len, u8 type) +{ + struct garp_port *port = rtnl_dereference(dev->garp_port); + struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]); + struct garp_attr *attr; + + spin_lock_bh(&app->lock); + attr = garp_attr_lookup(app, data, len, type); + if (!attr) { + spin_unlock_bh(&app->lock); + return; + } + garp_attr_event(app, attr, GARP_EVENT_REQ_LEAVE); + spin_unlock_bh(&app->lock); +} +EXPORT_SYMBOL_GPL(garp_request_leave); + +static void garp_gid_event(struct garp_applicant *app, enum garp_event event) +{ + struct rb_node *node, *next; + struct garp_attr *attr; + + for (node = rb_first(&app->gid); + next = node ? rb_next(node) : NULL, node != NULL; + node = next) { + attr = rb_entry(node, struct garp_attr, node); + garp_attr_event(app, attr, event); + } +} + +static void garp_join_timer_arm(struct garp_applicant *app) +{ + unsigned long delay; + + delay = (u64)msecs_to_jiffies(garp_join_time) * prandom_u32() >> 32; + mod_timer(&app->join_timer, jiffies + delay); +} + +static void garp_join_timer(struct timer_list *t) +{ + struct garp_applicant *app = from_timer(app, t, join_timer); + + spin_lock(&app->lock); + garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU); + garp_pdu_queue(app); + spin_unlock(&app->lock); + + garp_queue_xmit(app); + garp_join_timer_arm(app); +} + +static int garp_pdu_parse_end_mark(struct sk_buff *skb) +{ + if (!pskb_may_pull(skb, sizeof(u8))) + return -1; + if (*skb->data == GARP_END_MARK) { + skb_pull(skb, sizeof(u8)); + return -1; + } + return 0; +} + +static int garp_pdu_parse_attr(struct garp_applicant *app, struct sk_buff *skb, + u8 attrtype) +{ + const struct garp_attr_hdr *ga; + struct garp_attr *attr; + enum garp_event event; + unsigned int dlen; + + if (!pskb_may_pull(skb, sizeof(*ga))) + return -1; + ga = (struct garp_attr_hdr *)skb->data; + if (ga->len < sizeof(*ga)) + return -1; + + if (!pskb_may_pull(skb, ga->len)) + return -1; + skb_pull(skb, ga->len); + dlen = sizeof(*ga) - ga->len; + + if (attrtype > app->app->maxattr) + return 0; + + switch (ga->event) { + case GARP_LEAVE_ALL: + if (dlen != 0) + return -1; + garp_gid_event(app, GARP_EVENT_R_LEAVE_EMPTY); + return 0; + case GARP_JOIN_EMPTY: + event = GARP_EVENT_R_JOIN_EMPTY; + break; + case GARP_JOIN_IN: + event = GARP_EVENT_R_JOIN_IN; + break; + case GARP_LEAVE_EMPTY: + event = GARP_EVENT_R_LEAVE_EMPTY; + break; + case GARP_EMPTY: + event = GARP_EVENT_R_EMPTY; + break; + default: + return 0; + } + + if (dlen == 0) + return -1; + attr = garp_attr_lookup(app, ga->data, dlen, attrtype); + if (attr == NULL) + return 0; + garp_attr_event(app, attr, event); + return 0; +} + +static int garp_pdu_parse_msg(struct garp_applicant *app, struct sk_buff *skb) +{ + const struct garp_msg_hdr *gm; + + if (!pskb_may_pull(skb, sizeof(*gm))) + return -1; + gm = (struct garp_msg_hdr *)skb->data; + if (gm->attrtype == 0) + return -1; + skb_pull(skb, sizeof(*gm)); + + while (skb->len > 0) { + if (garp_pdu_parse_attr(app, skb, gm->attrtype) < 0) + return -1; + if (garp_pdu_parse_end_mark(skb) < 0) + break; + } + return 0; +} + +static void garp_pdu_rcv(const struct stp_proto *proto, struct sk_buff *skb, + struct net_device *dev) +{ + struct garp_application *appl = proto->data; + struct garp_port *port; + struct garp_applicant *app; + const struct garp_pdu_hdr *gp; + + port = rcu_dereference(dev->garp_port); + if (!port) + goto err; + app = rcu_dereference(port->applicants[appl->type]); + if (!app) + goto err; + + if (!pskb_may_pull(skb, sizeof(*gp))) + goto err; + gp = (struct garp_pdu_hdr *)skb->data; + if (get_unaligned(&gp->protocol) != htons(GARP_PROTOCOL_ID)) + goto err; + skb_pull(skb, sizeof(*gp)); + + spin_lock(&app->lock); + while (skb->len > 0) { + if (garp_pdu_parse_msg(app, skb) < 0) + break; + if (garp_pdu_parse_end_mark(skb) < 0) + break; + } + spin_unlock(&app->lock); +err: + kfree_skb(skb); +} + +static int garp_init_port(struct net_device *dev) +{ + struct garp_port *port; + + port = kzalloc(sizeof(*port), GFP_KERNEL); + if (!port) + return -ENOMEM; + rcu_assign_pointer(dev->garp_port, port); + return 0; +} + +static void garp_release_port(struct net_device *dev) +{ + struct garp_port *port = rtnl_dereference(dev->garp_port); + unsigned int i; + + for (i = 0; i <= GARP_APPLICATION_MAX; i++) { + if (rtnl_dereference(port->applicants[i])) + return; + } + RCU_INIT_POINTER(dev->garp_port, NULL); + kfree_rcu(port, rcu); +} + +int garp_init_applicant(struct net_device *dev, struct garp_application *appl) +{ + struct garp_applicant *app; + int err; + + ASSERT_RTNL(); + + if (!rtnl_dereference(dev->garp_port)) { + err = garp_init_port(dev); + if (err < 0) + goto err1; + } + + err = -ENOMEM; + app = kzalloc(sizeof(*app), GFP_KERNEL); + if (!app) + goto err2; + + err = dev_mc_add(dev, appl->proto.group_address); + if (err < 0) + goto err3; + + app->dev = dev; + app->app = appl; + app->gid = RB_ROOT; + spin_lock_init(&app->lock); + skb_queue_head_init(&app->queue); + rcu_assign_pointer(dev->garp_port->applicants[appl->type], app); + timer_setup(&app->join_timer, garp_join_timer, 0); + garp_join_timer_arm(app); + return 0; + +err3: + kfree(app); +err2: + garp_release_port(dev); +err1: + return err; +} +EXPORT_SYMBOL_GPL(garp_init_applicant); + +void garp_uninit_applicant(struct net_device *dev, struct garp_application *appl) +{ + struct garp_port *port = rtnl_dereference(dev->garp_port); + struct garp_applicant *app = rtnl_dereference(port->applicants[appl->type]); + + ASSERT_RTNL(); + + RCU_INIT_POINTER(port->applicants[appl->type], NULL); + + /* Delete timer and generate a final TRANSMIT_PDU event to flush out + * all pending messages before the applicant is gone. */ + del_timer_sync(&app->join_timer); + + spin_lock_bh(&app->lock); + garp_gid_event(app, GARP_EVENT_TRANSMIT_PDU); + garp_attr_destroy_all(app); + garp_pdu_queue(app); + spin_unlock_bh(&app->lock); + + garp_queue_xmit(app); + + dev_mc_del(dev, appl->proto.group_address); + kfree_rcu(app, rcu); + garp_release_port(dev); +} +EXPORT_SYMBOL_GPL(garp_uninit_applicant); + +int garp_register_application(struct garp_application *appl) +{ + appl->proto.rcv = garp_pdu_rcv; + appl->proto.data = appl; + return stp_proto_register(&appl->proto); +} +EXPORT_SYMBOL_GPL(garp_register_application); + +void garp_unregister_application(struct garp_application *appl) +{ + stp_proto_unregister(&appl->proto); +} +EXPORT_SYMBOL_GPL(garp_unregister_application); |