linux/drivers/w1/w1_netlink.c
Philipp Reisner 7069331dbe connector: Provide the sender's credentials to the callback
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Acked-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-02 10:54:01 -07:00

427 lines
9.7 KiB
C

/*
* w1_netlink.c
*
* Copyright (c) 2003 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
*
*
* 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
*/
#include <linux/skbuff.h>
#include <linux/netlink.h>
#include <linux/connector.h>
#include "w1.h"
#include "w1_log.h"
#include "w1_netlink.h"
#if defined(CONFIG_W1_CON) && (defined(CONFIG_CONNECTOR) || (defined(CONFIG_CONNECTOR_MODULE) && defined(CONFIG_W1_MODULE)))
void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
{
char buf[sizeof(struct cn_msg) + sizeof(struct w1_netlink_msg)];
struct cn_msg *m = (struct cn_msg *)buf;
struct w1_netlink_msg *w = (struct w1_netlink_msg *)(m+1);
memset(buf, 0, sizeof(buf));
m->id.idx = CN_W1_IDX;
m->id.val = CN_W1_VAL;
m->seq = dev->seq++;
m->len = sizeof(struct w1_netlink_msg);
memcpy(w, msg, sizeof(struct w1_netlink_msg));
cn_netlink_send(m, 0, GFP_KERNEL);
}
static void w1_send_slave(struct w1_master *dev, u64 rn)
{
struct cn_msg *msg = dev->priv;
struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
int avail;
avail = dev->priv_size - cmd->len;
if (avail > 8) {
u64 *data = (void *)(cmd + 1) + cmd->len;
*data = rn;
cmd->len += 8;
hdr->len += 8;
msg->len += 8;
return;
}
msg->ack++;
cn_netlink_send(msg, 0, GFP_KERNEL);
msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
hdr->len = sizeof(struct w1_netlink_cmd);
cmd->len = 0;
}
static int w1_process_search_command(struct w1_master *dev, struct cn_msg *msg,
unsigned int avail)
{
struct w1_netlink_msg *hdr = (struct w1_netlink_msg *)(msg + 1);
struct w1_netlink_cmd *cmd = (struct w1_netlink_cmd *)(hdr + 1);
int search_type = (cmd->cmd == W1_CMD_ALARM_SEARCH)?W1_ALARM_SEARCH:W1_SEARCH;
dev->priv = msg;
dev->priv_size = avail;
w1_search_devices(dev, search_type, w1_send_slave);
msg->ack = 0;
cn_netlink_send(msg, 0, GFP_KERNEL);
dev->priv = NULL;
dev->priv_size = 0;
return 0;
}
static int w1_send_read_reply(struct cn_msg *msg, struct w1_netlink_msg *hdr,
struct w1_netlink_cmd *cmd)
{
void *data;
struct w1_netlink_msg *h;
struct w1_netlink_cmd *c;
struct cn_msg *cm;
int err;
data = kzalloc(sizeof(struct cn_msg) +
sizeof(struct w1_netlink_msg) +
sizeof(struct w1_netlink_cmd) +
cmd->len, GFP_KERNEL);
if (!data)
return -ENOMEM;
cm = (struct cn_msg *)(data);
h = (struct w1_netlink_msg *)(cm + 1);
c = (struct w1_netlink_cmd *)(h + 1);
memcpy(cm, msg, sizeof(struct cn_msg));
memcpy(h, hdr, sizeof(struct w1_netlink_msg));
memcpy(c, cmd, sizeof(struct w1_netlink_cmd));
cm->ack = msg->seq+1;
cm->len = sizeof(struct w1_netlink_msg) +
sizeof(struct w1_netlink_cmd) + cmd->len;
h->len = sizeof(struct w1_netlink_cmd) + cmd->len;
memcpy(c->data, cmd->data, c->len);
err = cn_netlink_send(cm, 0, GFP_KERNEL);
kfree(data);
return err;
}
static int w1_process_command_io(struct w1_master *dev, struct cn_msg *msg,
struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
{
int err = 0;
switch (cmd->cmd) {
case W1_CMD_TOUCH:
w1_touch_block(dev, cmd->data, cmd->len);
w1_send_read_reply(msg, hdr, cmd);
break;
case W1_CMD_READ:
w1_read_block(dev, cmd->data, cmd->len);
w1_send_read_reply(msg, hdr, cmd);
break;
case W1_CMD_WRITE:
w1_write_block(dev, cmd->data, cmd->len);
break;
default:
err = -EINVAL;
break;
}
return err;
}
static int w1_process_command_master(struct w1_master *dev, struct cn_msg *req_msg,
struct w1_netlink_msg *req_hdr, struct w1_netlink_cmd *req_cmd)
{
int err = -EINVAL;
struct cn_msg *msg;
struct w1_netlink_msg *hdr;
struct w1_netlink_cmd *cmd;
msg = kzalloc(PAGE_SIZE, GFP_KERNEL);
if (!msg)
return -ENOMEM;
msg->id = req_msg->id;
msg->seq = req_msg->seq;
msg->ack = 0;
msg->len = sizeof(struct w1_netlink_msg) + sizeof(struct w1_netlink_cmd);
hdr = (struct w1_netlink_msg *)(msg + 1);
cmd = (struct w1_netlink_cmd *)(hdr + 1);
hdr->type = W1_MASTER_CMD;
hdr->id = req_hdr->id;
hdr->len = sizeof(struct w1_netlink_cmd);
cmd->cmd = req_cmd->cmd;
cmd->len = 0;
switch (cmd->cmd) {
case W1_CMD_SEARCH:
case W1_CMD_ALARM_SEARCH:
err = w1_process_search_command(dev, msg,
PAGE_SIZE - msg->len - sizeof(struct cn_msg));
break;
case W1_CMD_READ:
case W1_CMD_WRITE:
case W1_CMD_TOUCH:
err = w1_process_command_io(dev, req_msg, req_hdr, req_cmd);
break;
case W1_CMD_RESET:
err = w1_reset_bus(dev);
break;
default:
err = -EINVAL;
break;
}
kfree(msg);
return err;
}
static int w1_process_command_slave(struct w1_slave *sl, struct cn_msg *msg,
struct w1_netlink_msg *hdr, struct w1_netlink_cmd *cmd)
{
dev_dbg(&sl->master->dev, "%s: %02x.%012llx.%02x: cmd=%02x, len=%u.\n",
__func__, sl->reg_num.family, (unsigned long long)sl->reg_num.id,
sl->reg_num.crc, cmd->cmd, cmd->len);
return w1_process_command_io(sl->master, msg, hdr, cmd);
}
static int w1_process_command_root(struct cn_msg *msg, struct w1_netlink_msg *mcmd)
{
struct w1_master *m;
struct cn_msg *cn;
struct w1_netlink_msg *w;
u32 *id;
if (mcmd->type != W1_LIST_MASTERS) {
printk(KERN_NOTICE "%s: msg: %x.%x, wrong type: %u, len: %u.\n",
__func__, msg->id.idx, msg->id.val, mcmd->type, mcmd->len);
return -EPROTO;
}
cn = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!cn)
return -ENOMEM;
cn->id.idx = CN_W1_IDX;
cn->id.val = CN_W1_VAL;
cn->seq = msg->seq;
cn->ack = 1;
cn->len = sizeof(struct w1_netlink_msg);
w = (struct w1_netlink_msg *)(cn + 1);
w->type = W1_LIST_MASTERS;
w->status = 0;
w->len = 0;
id = (u32 *)(w + 1);
mutex_lock(&w1_mlock);
list_for_each_entry(m, &w1_masters, w1_master_entry) {
if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) {
cn_netlink_send(cn, 0, GFP_KERNEL);
cn->ack++;
cn->len = sizeof(struct w1_netlink_msg);
w->len = 0;
id = (u32 *)(w + 1);
}
*id = m->id;
w->len += sizeof(*id);
cn->len += sizeof(*id);
id++;
}
cn->ack = 0;
cn_netlink_send(cn, 0, GFP_KERNEL);
mutex_unlock(&w1_mlock);
kfree(cn);
return 0;
}
static int w1_netlink_send_error(struct cn_msg *rcmsg, struct w1_netlink_msg *rmsg,
struct w1_netlink_cmd *rcmd, int error)
{
struct cn_msg *cmsg;
struct w1_netlink_msg *msg;
struct w1_netlink_cmd *cmd;
cmsg = kzalloc(sizeof(*msg) + sizeof(*cmd) + sizeof(*cmsg), GFP_KERNEL);
if (!cmsg)
return -ENOMEM;
msg = (struct w1_netlink_msg *)(cmsg + 1);
cmd = (struct w1_netlink_cmd *)(msg + 1);
memcpy(cmsg, rcmsg, sizeof(*cmsg));
cmsg->len = sizeof(*msg);
memcpy(msg, rmsg, sizeof(*msg));
msg->len = 0;
msg->status = (short)-error;
if (rcmd) {
memcpy(cmd, rcmd, sizeof(*cmd));
cmd->len = 0;
msg->len += sizeof(*cmd);
cmsg->len += sizeof(*cmd);
}
error = cn_netlink_send(cmsg, 0, GFP_KERNEL);
kfree(cmsg);
return error;
}
static void w1_cn_callback(struct cn_msg *msg, struct netlink_skb_parms *nsp)
{
struct w1_netlink_msg *m = (struct w1_netlink_msg *)(msg + 1);
struct w1_netlink_cmd *cmd;
struct w1_slave *sl;
struct w1_master *dev;
int err = 0;
while (msg->len && !err) {
struct w1_reg_num id;
u16 mlen = m->len;
u8 *cmd_data = m->data;
dev = NULL;
sl = NULL;
cmd = NULL;
memcpy(&id, m->id.id, sizeof(id));
#if 0
printk("%s: %02x.%012llx.%02x: type=%02x, len=%u.\n",
__func__, id.family, (unsigned long long)id.id, id.crc, m->type, m->len);
#endif
if (m->len + sizeof(struct w1_netlink_msg) > msg->len) {
err = -E2BIG;
break;
}
if (m->type == W1_MASTER_CMD) {
dev = w1_search_master_id(m->id.mst.id);
} else if (m->type == W1_SLAVE_CMD) {
sl = w1_search_slave(&id);
if (sl)
dev = sl->master;
} else {
err = w1_process_command_root(msg, m);
goto out_cont;
}
if (!dev) {
err = -ENODEV;
goto out_cont;
}
err = 0;
if (!mlen)
goto out_cont;
mutex_lock(&dev->mutex);
if (sl && w1_reset_select_slave(sl)) {
err = -ENODEV;
goto out_up;
}
while (mlen) {
cmd = (struct w1_netlink_cmd *)cmd_data;
if (cmd->len + sizeof(struct w1_netlink_cmd) > mlen) {
err = -E2BIG;
break;
}
if (sl)
err = w1_process_command_slave(sl, msg, m, cmd);
else
err = w1_process_command_master(dev, msg, m, cmd);
w1_netlink_send_error(msg, m, cmd, err);
err = 0;
cmd_data += cmd->len + sizeof(struct w1_netlink_cmd);
mlen -= cmd->len + sizeof(struct w1_netlink_cmd);
}
out_up:
atomic_dec(&dev->refcnt);
if (sl)
atomic_dec(&sl->refcnt);
mutex_unlock(&dev->mutex);
out_cont:
if (!cmd || err)
w1_netlink_send_error(msg, m, cmd, err);
msg->len -= sizeof(struct w1_netlink_msg) + m->len;
m = (struct w1_netlink_msg *)(((u8 *)m) + sizeof(struct w1_netlink_msg) + m->len);
/*
* Let's allow requests for nonexisting devices.
*/
if (err == -ENODEV)
err = 0;
}
}
int w1_init_netlink(void)
{
struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
return cn_add_callback(&w1_id, "w1", &w1_cn_callback);
}
void w1_fini_netlink(void)
{
struct cb_id w1_id = {.idx = CN_W1_IDX, .val = CN_W1_VAL};
cn_del_callback(&w1_id);
}
#else
void w1_netlink_send(struct w1_master *dev, struct w1_netlink_msg *msg)
{
}
int w1_init_netlink(void)
{
return 0;
}
void w1_fini_netlink(void)
{
}
#endif