linux/linux-5.18.11/drivers/net/can/dev/netlink.c

625 lines
18 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
* Copyright (C) 2006 Andrey Volkov, Varma Electronics
* Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
* Copyright (C) 2021 Vincent Mailhol <mailhol.vincent@wanadoo.fr>
*/
#include <linux/can/dev.h>
#include <net/rtnetlink.h>
static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
[IFLA_CAN_STATE] = { .type = NLA_U32 },
[IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) },
[IFLA_CAN_RESTART_MS] = { .type = NLA_U32 },
[IFLA_CAN_RESTART] = { .type = NLA_U32 },
[IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) },
[IFLA_CAN_BITTIMING_CONST] = { .len = sizeof(struct can_bittiming_const) },
[IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) },
[IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
[IFLA_CAN_DATA_BITTIMING] = { .len = sizeof(struct can_bittiming) },
[IFLA_CAN_DATA_BITTIMING_CONST] = { .len = sizeof(struct can_bittiming_const) },
[IFLA_CAN_TERMINATION] = { .type = NLA_U16 },
[IFLA_CAN_TDC] = { .type = NLA_NESTED },
[IFLA_CAN_CTRLMODE_EXT] = { .type = NLA_NESTED },
};
static const struct nla_policy can_tdc_policy[IFLA_CAN_TDC_MAX + 1] = {
[IFLA_CAN_TDC_TDCV_MIN] = { .type = NLA_U32 },
[IFLA_CAN_TDC_TDCV_MAX] = { .type = NLA_U32 },
[IFLA_CAN_TDC_TDCO_MIN] = { .type = NLA_U32 },
[IFLA_CAN_TDC_TDCO_MAX] = { .type = NLA_U32 },
[IFLA_CAN_TDC_TDCF_MIN] = { .type = NLA_U32 },
[IFLA_CAN_TDC_TDCF_MAX] = { .type = NLA_U32 },
[IFLA_CAN_TDC_TDCV] = { .type = NLA_U32 },
[IFLA_CAN_TDC_TDCO] = { .type = NLA_U32 },
[IFLA_CAN_TDC_TDCF] = { .type = NLA_U32 },
};
static int can_validate(struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
bool is_can_fd = false;
/* Make sure that valid CAN FD configurations always consist of
* - nominal/arbitration bittiming
* - data bittiming
* - control mode with CAN_CTRLMODE_FD set
* - TDC parameters are coherent (details below)
*/
if (!data)
return 0;
if (data[IFLA_CAN_CTRLMODE]) {
struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
u32 tdc_flags = cm->flags & CAN_CTRLMODE_TDC_MASK;
is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD;
/* CAN_CTRLMODE_TDC_{AUTO,MANUAL} are mutually exclusive */
if (tdc_flags == CAN_CTRLMODE_TDC_MASK)
return -EOPNOTSUPP;
/* If one of the CAN_CTRLMODE_TDC_* flag is set then
* TDC must be set and vice-versa
*/
if (!!tdc_flags != !!data[IFLA_CAN_TDC])
return -EOPNOTSUPP;
/* If providing TDC parameters, at least TDCO is
* needed. TDCV is needed if and only if
* CAN_CTRLMODE_TDC_MANUAL is set
*/
if (data[IFLA_CAN_TDC]) {
struct nlattr *tb_tdc[IFLA_CAN_TDC_MAX + 1];
int err;
err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX,
data[IFLA_CAN_TDC],
can_tdc_policy, extack);
if (err)
return err;
if (tb_tdc[IFLA_CAN_TDC_TDCV]) {
if (tdc_flags & CAN_CTRLMODE_TDC_AUTO)
return -EOPNOTSUPP;
} else {
if (tdc_flags & CAN_CTRLMODE_TDC_MANUAL)
return -EOPNOTSUPP;
}
if (!tb_tdc[IFLA_CAN_TDC_TDCO])
return -EOPNOTSUPP;
}
}
if (is_can_fd) {
if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
return -EOPNOTSUPP;
}
if (data[IFLA_CAN_DATA_BITTIMING] || data[IFLA_CAN_TDC]) {
if (!is_can_fd)
return -EOPNOTSUPP;
}
return 0;
}
static int can_tdc_changelink(struct can_priv *priv, const struct nlattr *nla,
struct netlink_ext_ack *extack)
{
struct nlattr *tb_tdc[IFLA_CAN_TDC_MAX + 1];
struct can_tdc tdc = { 0 };
const struct can_tdc_const *tdc_const = priv->tdc_const;
int err;
if (!tdc_const || !can_tdc_is_enabled(priv))
return -EOPNOTSUPP;
err = nla_parse_nested(tb_tdc, IFLA_CAN_TDC_MAX, nla,
can_tdc_policy, extack);
if (err)
return err;
if (tb_tdc[IFLA_CAN_TDC_TDCV]) {
u32 tdcv = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCV]);
if (tdcv < tdc_const->tdcv_min || tdcv > tdc_const->tdcv_max)
return -EINVAL;
tdc.tdcv = tdcv;
}
if (tb_tdc[IFLA_CAN_TDC_TDCO]) {
u32 tdco = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCO]);
if (tdco < tdc_const->tdco_min || tdco > tdc_const->tdco_max)
return -EINVAL;
tdc.tdco = tdco;
}
if (tb_tdc[IFLA_CAN_TDC_TDCF]) {
u32 tdcf = nla_get_u32(tb_tdc[IFLA_CAN_TDC_TDCF]);
if (tdcf < tdc_const->tdcf_min || tdcf > tdc_const->tdcf_max)
return -EINVAL;
tdc.tdcf = tdcf;
}
priv->tdc = tdc;
return 0;
}
static int can_changelink(struct net_device *dev, struct nlattr *tb[],
struct nlattr *data[],
struct netlink_ext_ack *extack)
{
struct can_priv *priv = netdev_priv(dev);
u32 tdc_mask = 0;
int err;
/* We need synchronization with dev->stop() */
ASSERT_RTNL();
if (data[IFLA_CAN_BITTIMING]) {
struct can_bittiming bt;
/* Do not allow changing bittiming while running */
if (dev->flags & IFF_UP)
return -EBUSY;
/* Calculate bittiming parameters based on
* bittiming_const if set, otherwise pass bitrate
* directly via do_set_bitrate(). Bail out if neither
* is given.
*/
if (!priv->bittiming_const && !priv->do_set_bittiming)
return -EOPNOTSUPP;
memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
err = can_get_bittiming(dev, &bt,
priv->bittiming_const,
priv->bitrate_const,
priv->bitrate_const_cnt);
if (err)
return err;
if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) {
netdev_err(dev, "arbitration bitrate surpasses transceiver capabilities of %d bps\n",
priv->bitrate_max);
return -EINVAL;
}
memcpy(&priv->bittiming, &bt, sizeof(bt));
if (priv->do_set_bittiming) {
/* Finally, set the bit-timing registers */
err = priv->do_set_bittiming(dev);
if (err)
return err;
}
}
if (data[IFLA_CAN_CTRLMODE]) {
struct can_ctrlmode *cm;
u32 ctrlstatic;
u32 maskedflags;
/* Do not allow changing controller mode while running */
if (dev->flags & IFF_UP)
return -EBUSY;
cm = nla_data(data[IFLA_CAN_CTRLMODE]);
ctrlstatic = can_get_static_ctrlmode(priv);
maskedflags = cm->flags & cm->mask;
/* check whether provided bits are allowed to be passed */
if (maskedflags & ~(priv->ctrlmode_supported | ctrlstatic))
return -EOPNOTSUPP;
/* do not check for static fd-non-iso if 'fd' is disabled */
if (!(maskedflags & CAN_CTRLMODE_FD))
ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
/* make sure static options are provided by configuration */
if ((maskedflags & ctrlstatic) != ctrlstatic)
return -EOPNOTSUPP;
/* clear bits to be modified and copy the flag values */
priv->ctrlmode &= ~cm->mask;
priv->ctrlmode |= maskedflags;
/* CAN_CTRLMODE_FD can only be set when driver supports FD */
if (priv->ctrlmode & CAN_CTRLMODE_FD) {
dev->mtu = CANFD_MTU;
} else {
dev->mtu = CAN_MTU;
memset(&priv->data_bittiming, 0,
sizeof(priv->data_bittiming));
priv->ctrlmode &= ~CAN_CTRLMODE_TDC_MASK;
memset(&priv->tdc, 0, sizeof(priv->tdc));
}
tdc_mask = cm->mask & CAN_CTRLMODE_TDC_MASK;
/* CAN_CTRLMODE_TDC_{AUTO,MANUAL} are mutually
* exclusive: make sure to turn the other one off
*/
if (tdc_mask)
priv->ctrlmode &= cm->flags | ~CAN_CTRLMODE_TDC_MASK;
}
if (data[IFLA_CAN_RESTART_MS]) {
/* Do not allow changing restart delay while running */
if (dev->flags & IFF_UP)
return -EBUSY;
priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
}
if (data[IFLA_CAN_RESTART]) {
/* Do not allow a restart while not running */
if (!(dev->flags & IFF_UP))
return -EINVAL;
err = can_restart_now(dev);
if (err)
return err;
}
if (data[IFLA_CAN_DATA_BITTIMING]) {
struct can_bittiming dbt;
/* Do not allow changing bittiming while running */
if (dev->flags & IFF_UP)
return -EBUSY;
/* Calculate bittiming parameters based on
* data_bittiming_const if set, otherwise pass bitrate
* directly via do_set_bitrate(). Bail out if neither
* is given.
*/
if (!priv->data_bittiming_const && !priv->do_set_data_bittiming)
return -EOPNOTSUPP;
memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
sizeof(dbt));
err = can_get_bittiming(dev, &dbt,
priv->data_bittiming_const,
priv->data_bitrate_const,
priv->data_bitrate_const_cnt);
if (err)
return err;
if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
netdev_err(dev, "canfd data bitrate surpasses transceiver capabilities of %d bps\n",
priv->bitrate_max);
return -EINVAL;
}
memset(&priv->tdc, 0, sizeof(priv->tdc));
if (data[IFLA_CAN_TDC]) {
/* TDC parameters are provided: use them */
err = can_tdc_changelink(priv, data[IFLA_CAN_TDC],
extack);
if (err) {
priv->ctrlmode &= ~CAN_CTRLMODE_TDC_MASK;
return err;
}
} else if (!tdc_mask) {
/* Neither of TDC parameters nor TDC flags are
* provided: do calculation
*/
can_calc_tdco(&priv->tdc, priv->tdc_const, &priv->data_bittiming,
&priv->ctrlmode, priv->ctrlmode_supported);
} /* else: both CAN_CTRLMODE_TDC_{AUTO,MANUAL} are explicitly
* turned off. TDC is disabled: do nothing
*/
memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
if (priv->do_set_data_bittiming) {
/* Finally, set the bit-timing registers */
err = priv->do_set_data_bittiming(dev);
if (err)
return err;
}
}
if (data[IFLA_CAN_TERMINATION]) {
const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]);
const unsigned int num_term = priv->termination_const_cnt;
unsigned int i;
if (!priv->do_set_termination)
return -EOPNOTSUPP;
/* check whether given value is supported by the interface */
for (i = 0; i < num_term; i++) {
if (termval == priv->termination_const[i])
break;
}
if (i >= num_term)
return -EINVAL;
/* Finally, set the termination value */
err = priv->do_set_termination(dev, termval);
if (err)
return err;
priv->termination = termval;
}
return 0;
}
static size_t can_tdc_get_size(const struct net_device *dev)
{
struct can_priv *priv = netdev_priv(dev);
size_t size;
if (!priv->tdc_const)
return 0;
size = nla_total_size(0); /* nest IFLA_CAN_TDC */
if (priv->ctrlmode_supported & CAN_CTRLMODE_TDC_MANUAL) {
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCV_MIN */
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCV_MAX */
}
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCO_MIN */
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCO_MAX */
if (priv->tdc_const->tdcf_max) {
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCF_MIN */
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCF_MAX */
}
if (can_tdc_is_enabled(priv)) {
if (priv->ctrlmode & CAN_CTRLMODE_TDC_MANUAL ||
priv->do_get_auto_tdcv)
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCV */
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCO */
if (priv->tdc_const->tdcf_max)
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_TDCF */
}
return size;
}
static size_t can_ctrlmode_ext_get_size(void)
{
return nla_total_size(0) + /* nest IFLA_CAN_CTRLMODE_EXT */
nla_total_size(sizeof(u32)); /* IFLA_CAN_CTRLMODE_SUPPORTED */
}
static size_t can_get_size(const struct net_device *dev)
{
struct can_priv *priv = netdev_priv(dev);
size_t size = 0;
if (priv->bittiming.bitrate) /* IFLA_CAN_BITTIMING */
size += nla_total_size(sizeof(struct can_bittiming));
if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */
size += nla_total_size(sizeof(struct can_bittiming_const));
size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */
size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */
size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */
if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */
size += nla_total_size(sizeof(struct can_berr_counter));
if (priv->data_bittiming.bitrate) /* IFLA_CAN_DATA_BITTIMING */
size += nla_total_size(sizeof(struct can_bittiming));
if (priv->data_bittiming_const) /* IFLA_CAN_DATA_BITTIMING_CONST */
size += nla_total_size(sizeof(struct can_bittiming_const));
if (priv->termination_const) {
size += nla_total_size(sizeof(priv->termination)); /* IFLA_CAN_TERMINATION */
size += nla_total_size(sizeof(*priv->termination_const) * /* IFLA_CAN_TERMINATION_CONST */
priv->termination_const_cnt);
}
if (priv->bitrate_const) /* IFLA_CAN_BITRATE_CONST */
size += nla_total_size(sizeof(*priv->bitrate_const) *
priv->bitrate_const_cnt);
if (priv->data_bitrate_const) /* IFLA_CAN_DATA_BITRATE_CONST */
size += nla_total_size(sizeof(*priv->data_bitrate_const) *
priv->data_bitrate_const_cnt);
size += sizeof(priv->bitrate_max); /* IFLA_CAN_BITRATE_MAX */
size += can_tdc_get_size(dev); /* IFLA_CAN_TDC */
size += can_ctrlmode_ext_get_size(); /* IFLA_CAN_CTRLMODE_EXT */
return size;
}
static int can_tdc_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct nlattr *nest;
struct can_priv *priv = netdev_priv(dev);
struct can_tdc *tdc = &priv->tdc;
const struct can_tdc_const *tdc_const = priv->tdc_const;
if (!tdc_const)
return 0;
nest = nla_nest_start(skb, IFLA_CAN_TDC);
if (!nest)
return -EMSGSIZE;
if (priv->ctrlmode_supported & CAN_CTRLMODE_TDC_MANUAL &&
(nla_put_u32(skb, IFLA_CAN_TDC_TDCV_MIN, tdc_const->tdcv_min) ||
nla_put_u32(skb, IFLA_CAN_TDC_TDCV_MAX, tdc_const->tdcv_max)))
goto err_cancel;
if (nla_put_u32(skb, IFLA_CAN_TDC_TDCO_MIN, tdc_const->tdco_min) ||
nla_put_u32(skb, IFLA_CAN_TDC_TDCO_MAX, tdc_const->tdco_max))
goto err_cancel;
if (tdc_const->tdcf_max &&
(nla_put_u32(skb, IFLA_CAN_TDC_TDCF_MIN, tdc_const->tdcf_min) ||
nla_put_u32(skb, IFLA_CAN_TDC_TDCF_MAX, tdc_const->tdcf_max)))
goto err_cancel;
if (can_tdc_is_enabled(priv)) {
u32 tdcv;
int err = -EINVAL;
if (priv->ctrlmode & CAN_CTRLMODE_TDC_MANUAL) {
tdcv = tdc->tdcv;
err = 0;
} else if (priv->do_get_auto_tdcv) {
err = priv->do_get_auto_tdcv(dev, &tdcv);
}
if (!err && nla_put_u32(skb, IFLA_CAN_TDC_TDCV, tdcv))
goto err_cancel;
if (nla_put_u32(skb, IFLA_CAN_TDC_TDCO, tdc->tdco))
goto err_cancel;
if (tdc_const->tdcf_max &&
nla_put_u32(skb, IFLA_CAN_TDC_TDCF, tdc->tdcf))
goto err_cancel;
}
nla_nest_end(skb, nest);
return 0;
err_cancel:
nla_nest_cancel(skb, nest);
return -EMSGSIZE;
}
static int can_ctrlmode_ext_fill_info(struct sk_buff *skb,
const struct can_priv *priv)
{
struct nlattr *nest;
nest = nla_nest_start(skb, IFLA_CAN_CTRLMODE_EXT);
if (!nest)
return -EMSGSIZE;
if (nla_put_u32(skb, IFLA_CAN_CTRLMODE_SUPPORTED,
priv->ctrlmode_supported)) {
nla_nest_cancel(skb, nest);
return -EMSGSIZE;
}
nla_nest_end(skb, nest);
return 0;
}
static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
{
struct can_priv *priv = netdev_priv(dev);
struct can_ctrlmode cm = {.flags = priv->ctrlmode};
struct can_berr_counter bec = { };
enum can_state state = priv->state;
if (priv->do_get_state)
priv->do_get_state(dev, &state);
if ((priv->bittiming.bitrate &&
nla_put(skb, IFLA_CAN_BITTIMING,
sizeof(priv->bittiming), &priv->bittiming)) ||
(priv->bittiming_const &&
nla_put(skb, IFLA_CAN_BITTIMING_CONST,
sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) ||
nla_put_u32(skb, IFLA_CAN_STATE, state) ||
nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
(priv->do_get_berr_counter &&
!priv->do_get_berr_counter(dev, &bec) &&
nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
(priv->data_bittiming.bitrate &&
nla_put(skb, IFLA_CAN_DATA_BITTIMING,
sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
(priv->data_bittiming_const &&
nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
sizeof(*priv->data_bittiming_const),
priv->data_bittiming_const)) ||
(priv->termination_const &&
(nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) ||
nla_put(skb, IFLA_CAN_TERMINATION_CONST,
sizeof(*priv->termination_const) *
priv->termination_const_cnt,
priv->termination_const))) ||
(priv->bitrate_const &&
nla_put(skb, IFLA_CAN_BITRATE_CONST,
sizeof(*priv->bitrate_const) *
priv->bitrate_const_cnt,
priv->bitrate_const)) ||
(priv->data_bitrate_const &&
nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST,
sizeof(*priv->data_bitrate_const) *
priv->data_bitrate_const_cnt,
priv->data_bitrate_const)) ||
(nla_put(skb, IFLA_CAN_BITRATE_MAX,
sizeof(priv->bitrate_max),
&priv->bitrate_max)) ||
can_tdc_fill_info(skb, dev) ||
can_ctrlmode_ext_fill_info(skb, priv)
)
return -EMSGSIZE;
return 0;
}
static size_t can_get_xstats_size(const struct net_device *dev)
{
return sizeof(struct can_device_stats);
}
static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
{
struct can_priv *priv = netdev_priv(dev);
if (nla_put(skb, IFLA_INFO_XSTATS,
sizeof(priv->can_stats), &priv->can_stats))
goto nla_put_failure;
return 0;
nla_put_failure:
return -EMSGSIZE;
}
static int can_newlink(struct net *src_net, struct net_device *dev,
struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
return -EOPNOTSUPP;
}
static void can_dellink(struct net_device *dev, struct list_head *head)
{
}
struct rtnl_link_ops can_link_ops __read_mostly = {
.kind = "can",
.netns_refund = true,
.maxtype = IFLA_CAN_MAX,
.policy = can_policy,
.setup = can_setup,
.validate = can_validate,
.newlink = can_newlink,
.changelink = can_changelink,
.dellink = can_dellink,
.get_size = can_get_size,
.fill_info = can_fill_info,
.get_xstats_size = can_get_xstats_size,
.fill_xstats = can_fill_xstats,
};
int can_netlink_register(void)
{
return rtnl_link_register(&can_link_ops);
}
void can_netlink_unregister(void)
{
rtnl_link_unregister(&can_link_ops);
}