- 根目录:
- net
- nfc
- netlink.c
/*
* Copyright (C) 2011 Instituto Nokia de Tecnologia
*
* Authors:
* Lauro Ramos Venancio <lauro.venancio@openbossa.org>
* Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the
* Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
#include <net/genetlink.h>
#include <linux/nfc.h>
#include <linux/slab.h>
#include "nfc.h"
static struct genl_multicast_group nfc_genl_event_mcgrp = {
.name = NFC_GENL_MCAST_EVENT_NAME,
};
struct genl_family nfc_genl_family = {
.id = GENL_ID_GENERATE,
.hdrsize = 0,
.name = NFC_GENL_NAME,
.version = NFC_GENL_VERSION,
.maxattr = NFC_ATTR_MAX,
};
static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = {
[NFC_ATTR_DEVICE_INDEX] = { .type = NLA_U32 },
[NFC_ATTR_DEVICE_NAME] = { .type = NLA_STRING,
.len = NFC_DEVICE_NAME_MAXSIZE },
[NFC_ATTR_PROTOCOLS] = { .type = NLA_U32 },
[NFC_ATTR_COMM_MODE] = { .type = NLA_U8 },
[NFC_ATTR_RF_MODE] = { .type = NLA_U8 },
};
static int nfc_genl_send_target(struct sk_buff *msg, struct nfc_target *target,
struct netlink_callback *cb, int flags)
{
void *hdr;
hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
&nfc_genl_family, flags, NFC_CMD_GET_TARGET);
if (!hdr)
return -EMSGSIZE;
genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
NLA_PUT_U32(msg, NFC_ATTR_TARGET_INDEX, target->idx);
NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS,
target->supported_protocols);
NLA_PUT_U16(msg, NFC_ATTR_TARGET_SENS_RES, target->sens_res);
NLA_PUT_U8(msg, NFC_ATTR_TARGET_SEL_RES, target->sel_res);
if (target->nfcid1_len > 0)
NLA_PUT(msg, NFC_ATTR_TARGET_NFCID1, target->nfcid1_len,
target->nfcid1);
return genlmsg_end(msg, hdr);
nla_put_failure:
genlmsg_cancel(msg, hdr);
return -EMSGSIZE;
}
static struct nfc_dev *__get_device_from_cb(struct netlink_callback *cb)
{
struct nfc_dev *dev;
int rc;
u32 idx;
rc = nlmsg_parse(cb->nlh, GENL_HDRLEN + nfc_genl_family.hdrsize,
nfc_genl_family.attrbuf,
nfc_genl_family.maxattr,
nfc_genl_policy);
if (rc < 0)
return ERR_PTR(rc);
if (!nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX])
return ERR_PTR(-EINVAL);
idx = nla_get_u32(nfc_genl_family.attrbuf[NFC_ATTR_DEVICE_INDEX]);
dev = nfc_get_device(idx);
if (!dev)
return ERR_PTR(-ENODEV);
return dev;
}
static int nfc_genl_dump_targets(struct sk_buff *skb,
struct netlink_callback *cb)
{
int i = cb->args[0];
struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
int rc;
if (!dev) {
dev = __get_device_from_cb(cb);
if (IS_ERR(dev))
return PTR_ERR(dev);
cb->args[1] = (long) dev;
}
spin_lock_bh(&dev->targets_lock);
cb->seq = dev->targets_generation;
while (i < dev->n_targets) {
rc = nfc_genl_send_target(skb, &dev->targets[i], cb,
NLM_F_MULTI);
if (rc < 0)
break;
i++;
}
spin_unlock_bh(&dev->targets_lock);
cb->args[0] = i;
return skb->len;
}
static int nfc_genl_dump_targets_done(struct netlink_callback *cb)
{
struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
if (dev)
nfc_put_device(dev);
return 0;
}
int nfc_genl_targets_found(struct nfc_dev *dev)
{
struct sk_buff *msg;
void *hdr;
dev->genl_data.poll_req_pid = 0;
msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
if (!msg)
return -ENOMEM;
hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
NFC_EVENT_TARGETS_FOUND);
if (!hdr)
goto free_msg;
NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
genlmsg_end(msg, hdr);
return genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
nla_put_failure:
genlmsg_cancel(msg, hdr);
free_msg:
nlmsg_free(msg);
return -EMSGSIZE;
}
int nfc_genl_device_added(struct nfc_dev *dev)
{
struct sk_buff *msg;
void *hdr;
msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
if (!msg)
return -ENOMEM;
hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
NFC_EVENT_DEVICE_ADDED);
if (!hdr)
goto free_msg;
NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev));
NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols);
genlmsg_end(msg, hdr);
genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
return 0;
nla_put_failure:
genlmsg_cancel(msg, hdr);
free_msg:
nlmsg_free(msg);
return -EMSGSIZE;
}
int nfc_genl_device_removed(struct nfc_dev *dev)
{
struct sk_buff *msg;
void *hdr;
msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
if (!msg)
return -ENOMEM;
hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
NFC_EVENT_DEVICE_REMOVED);
if (!hdr)
goto free_msg;
NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
genlmsg_end(msg, hdr);
genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
return 0;
nla_put_failure:
genlmsg_cancel(msg, hdr);
free_msg:
nlmsg_free(msg);
return -EMSGSIZE;
}
static int nfc_genl_send_device(struct sk_buff *msg, struct nfc_dev *dev,
u32 pid, u32 seq,
struct netlink_callback *cb,
int flags)
{
void *hdr;
hdr = genlmsg_put(msg, pid, seq, &nfc_genl_family, flags,
NFC_CMD_GET_DEVICE);
if (!hdr)
return -EMSGSIZE;
if (cb)
genl_dump_check_consistent(cb, hdr, &nfc_genl_family);
NLA_PUT_STRING(msg, NFC_ATTR_DEVICE_NAME, nfc_device_name(dev));
NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
NLA_PUT_U32(msg, NFC_ATTR_PROTOCOLS, dev->supported_protocols);
return genlmsg_end(msg, hdr);
nla_put_failure:
genlmsg_cancel(msg, hdr);
return -EMSGSIZE;
}
static int nfc_genl_dump_devices(struct sk_buff *skb,
struct netlink_callback *cb)
{
struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];
struct nfc_dev *dev = (struct nfc_dev *) cb->args[1];
bool first_call = false;
if (!iter) {
first_call = true;
iter = kmalloc(sizeof(struct class_dev_iter), GFP_KERNEL);
if (!iter)
return -ENOMEM;
cb->args[0] = (long) iter;
}
mutex_lock(&nfc_devlist_mutex);
cb->seq = nfc_devlist_generation;
if (first_call) {
nfc_device_iter_init(iter);
dev = nfc_device_iter_next(iter);
}
while (dev) {
int rc;
rc = nfc_genl_send_device(skb, dev, NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq,
cb, NLM_F_MULTI);
if (rc < 0)
break;
dev = nfc_device_iter_next(iter);
}
mutex_unlock(&nfc_devlist_mutex);
cb->args[1] = (long) dev;
return skb->len;
}
static int nfc_genl_dump_devices_done(struct netlink_callback *cb)
{
struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];
nfc_device_iter_exit(iter);
kfree(iter);
return 0;
}
int nfc_genl_dep_link_up_event(struct nfc_dev *dev, u32 target_idx,
u8 comm_mode, u8 rf_mode)
{
struct sk_buff *msg;
void *hdr;
pr_debug("DEP link is up\n");
msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
if (!msg)
return -ENOMEM;
hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
NFC_CMD_DEP_LINK_UP);
if (!hdr)
goto free_msg;
NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
if (rf_mode == NFC_RF_INITIATOR)
NLA_PUT_U32(msg, NFC_ATTR_TARGET_INDEX, target_idx);
NLA_PUT_U8(msg, NFC_ATTR_COMM_MODE, comm_mode);
NLA_PUT_U8(msg, NFC_ATTR_RF_MODE, rf_mode);
genlmsg_end(msg, hdr);
dev->dep_link_up = true;
genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
return 0;
nla_put_failure:
genlmsg_cancel(msg, hdr);
free_msg:
nlmsg_free(msg);
return -EMSGSIZE;
}
int nfc_genl_dep_link_down_event(struct nfc_dev *dev)
{
struct sk_buff *msg;
void *hdr;
pr_debug("DEP link is down\n");
msg = nlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
if (!msg)
return -ENOMEM;
hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
NFC_CMD_DEP_LINK_DOWN);
if (!hdr)
goto free_msg;
NLA_PUT_U32(msg, NFC_ATTR_DEVICE_INDEX, dev->idx);
genlmsg_end(msg, hdr);
genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_ATOMIC);
return 0;
nla_put_failure:
genlmsg_cancel(msg, hdr);
free_msg:
nlmsg_free(msg);
return -EMSGSIZE;
}
static int nfc_genl_get_device(struct sk_buff *skb, struct genl_info *info)
{
struct sk_buff *msg;
struct nfc_dev *dev;
u32 idx;
int rc = -ENOBUFS;
if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
return -EINVAL;
idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
dev = nfc_get_device(idx);
if (!dev)
return -ENODEV;
msg = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
if (!msg) {
rc = -ENOMEM;
goto out_putdev;
}
rc = nfc_genl_send_device(msg, dev, info->snd_pid, info->snd_seq,
NULL, 0);
if (rc < 0)
goto out_free;
nfc_put_device(dev);
return genlmsg_reply(msg, info);
out_free:
nlmsg_free(msg);
out_putdev:
nfc_put_device(dev);
return rc;
}
static int nfc_genl_dev_up(struct sk_buff *skb, struct genl_info *info)
{
struct nfc_dev *dev;
int rc;
u32 idx;
if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
return -EINVAL;
idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
dev = nfc_get_device(idx);
if (!dev)
return -ENODEV;
rc = nfc_dev_up(dev);
nfc_put_device(dev);
return rc;
}
static int nfc_genl_dev_down(struct sk_buff *skb, struct genl_info *info)
{
struct nfc_dev *dev;
int rc;
u32 idx;
if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
return -EINVAL;
idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
dev = nfc_get_device(idx);
if (!dev)
return -ENODEV;
rc = nfc_dev_down(dev);
nfc_put_device(dev);
return rc;
}
static int nfc_genl_start_poll(struct sk_buff *skb, struct genl_info *info)
{
struct nfc_dev *dev;
int rc;
u32 idx;
u32 protocols;
pr_debug("Poll start\n");
if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
!info->attrs[NFC_ATTR_PROTOCOLS])
return -EINVAL;
idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
protocols = nla_get_u32(info->attrs[NFC_ATTR_PROTOCOLS]);
dev = nfc_get_device(idx);
if (!dev)
return -ENODEV;
mutex_lock(&dev->genl_data.genl_data_mutex);
rc = nfc_start_poll(dev, protocols);
if (!rc)
dev->genl_data.poll_req_pid = info->snd_pid;
mutex_unlock(&dev->genl_data.genl_data_mutex);
nfc_put_device(dev);
return rc;
}
static int nfc_genl_stop_poll(struct sk_buff *skb, struct genl_info *info)
{
struct nfc_dev *dev;
int rc;
u32 idx;
if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
return -EINVAL;
idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
dev = nfc_get_device(idx);
if (!dev)
return -ENODEV;
mutex_lock(&dev->genl_data.genl_data_mutex);
if (dev->genl_data.poll_req_pid != info->snd_pid) {
rc = -EBUSY;
goto out;
}
rc = nfc_stop_poll(dev);
dev->genl_data.poll_req_pid = 0;
out:
mutex_unlock(&dev->genl_data.genl_data_mutex);
nfc_put_device(dev);
return rc;
}
static int nfc_genl_dep_link_up(struct sk_buff *skb, struct genl_info *info)
{
struct nfc_dev *dev;
int rc, tgt_idx;
u32 idx;
u8 comm, rf;
pr_debug("DEP link up\n");
if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
!info->attrs[NFC_ATTR_COMM_MODE] ||
!info->attrs[NFC_ATTR_RF_MODE])
return -EINVAL;
idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
if (!info->attrs[NFC_ATTR_TARGET_INDEX])
tgt_idx = NFC_TARGET_IDX_ANY;
else
tgt_idx = nla_get_u32(info->attrs[NFC_ATTR_TARGET_INDEX]);
comm = nla_get_u8(info->attrs[NFC_ATTR_COMM_MODE]);
rf = nla_get_u8(info->attrs[NFC_ATTR_RF_MODE]);
if (comm != NFC_COMM_ACTIVE && comm != NFC_COMM_PASSIVE)
return -EINVAL;
if (rf != NFC_RF_INITIATOR && comm != NFC_RF_TARGET)
return -EINVAL;
dev = nfc_get_device(idx);
if (!dev)
return -ENODEV;
rc = nfc_dep_link_up(dev, tgt_idx, comm, rf);
nfc_put_device(dev);
return rc;
}
static int nfc_genl_dep_link_down(struct sk_buff *skb, struct genl_info *info)
{
struct nfc_dev *dev;
int rc;
u32 idx;
if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
return -EINVAL;
idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
dev = nfc_get_device(idx);
if (!dev)
return -ENODEV;
rc = nfc_dep_link_down(dev);
nfc_put_device(dev);
return rc;
}
static struct genl_ops nfc_genl_ops[] = {
{
.cmd = NFC_CMD_GET_DEVICE,
.doit = nfc_genl_get_device,
.dumpit = nfc_genl_dump_devices,
.done = nfc_genl_dump_devices_done,
.policy = nfc_genl_policy,
},
{
.cmd = NFC_CMD_DEV_UP,
.doit = nfc_genl_dev_up,
.policy = nfc_genl_policy,
},
{
.cmd = NFC_CMD_DEV_DOWN,
.doit = nfc_genl_dev_down,
.policy = nfc_genl_policy,
},
{
.cmd = NFC_CMD_START_POLL,
.doit = nfc_genl_start_poll,
.policy = nfc_genl_policy,
},
{
.cmd = NFC_CMD_STOP_POLL,
.doit = nfc_genl_stop_poll,
.policy = nfc_genl_policy,
},
{
.cmd = NFC_CMD_DEP_LINK_UP,
.doit = nfc_genl_dep_link_up,
.policy = nfc_genl_policy,
},
{
.cmd = NFC_CMD_DEP_LINK_DOWN,
.doit = nfc_genl_dep_link_down,
.policy = nfc_genl_policy,
},
{
.cmd = NFC_CMD_GET_TARGET,
.dumpit = nfc_genl_dump_targets,
.done = nfc_genl_dump_targets_done,
.policy = nfc_genl_policy,
},
};
static int nfc_genl_rcv_nl_event(struct notifier_block *this,
unsigned long event, void *ptr)
{
struct netlink_notify *n = ptr;
struct class_dev_iter iter;
struct nfc_dev *dev;
if (event != NETLINK_URELEASE || n->protocol != NETLINK_GENERIC)
goto out;
pr_debug("NETLINK_URELEASE event from id %d\n", n->pid);
nfc_device_iter_init(&iter);
dev = nfc_device_iter_next(&iter);
while (dev) {
if (dev->genl_data.poll_req_pid == n->pid) {
nfc_stop_poll(dev);
dev->genl_data.poll_req_pid = 0;
}
dev = nfc_device_iter_next(&iter);
}
nfc_device_iter_exit(&iter);
out:
return NOTIFY_DONE;
}
void nfc_genl_data_init(struct nfc_genl_data *genl_data)
{
genl_data->poll_req_pid = 0;
mutex_init(&genl_data->genl_data_mutex);
}
void nfc_genl_data_exit(struct nfc_genl_data *genl_data)
{
mutex_destroy(&genl_data->genl_data_mutex);
}
static struct notifier_block nl_notifier = {
.notifier_call = nfc_genl_rcv_nl_event,
};
/**
* nfc_genl_init() - Initialize netlink interface
*
* This initialization function registers the nfc netlink family.
*/
int __init nfc_genl_init(void)
{
int rc;
rc = genl_register_family_with_ops(&nfc_genl_family, nfc_genl_ops,
ARRAY_SIZE(nfc_genl_ops));
if (rc)
return rc;
rc = genl_register_mc_group(&nfc_genl_family, &nfc_genl_event_mcgrp);
netlink_register_notifier(&nl_notifier);
return rc;
}
/**
* nfc_genl_exit() - Deinitialize netlink interface
*
* This exit function unregisters the nfc netlink family.
*/
void nfc_genl_exit(void)
{
netlink_unregister_notifier(&nl_notifier);
genl_unregister_family(&nfc_genl_family);
}