act_skbedit.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2008, Intel Corporation.
*
* Author: Alexander Duyck <alexander.h.duyck@intel.com>
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/dsfield.h>
#include <net/pkt_cls.h>
#include <net/tc_wrapper.h>
#include <linux/tc_act/tc_skbedit.h>
#include <net/tc_act/tc_skbedit.h>
static struct tc_action_ops act_skbedit_ops;
static u16 tcf_skbedit_hash(struct tcf_skbedit_params *params,
struct sk_buff *skb)
{
u16 queue_mapping = params->queue_mapping;
if (params->flags & SKBEDIT_F_TXQ_SKBHASH) {
u32 hash = skb_get_hash(skb);
queue_mapping += hash % params->mapping_mod;
}
return netdev_cap_txqueue(skb->dev, queue_mapping);
}
TC_INDIRECT_SCOPE int tcf_skbedit_act(struct sk_buff *skb,
const struct tc_action *a,
struct tcf_result *res)
{
struct tcf_skbedit *d = to_skbedit(a);
struct tcf_skbedit_params *params;
int action;
tcf_lastuse_update(&d->tcf_tm);
bstats_update(this_cpu_ptr(d->common.cpu_bstats), skb);
params = rcu_dereference_bh(d->params);
action = READ_ONCE(d->tcf_action);
if (params->flags & SKBEDIT_F_PRIORITY)
skb->priority = params->priority;
if (params->flags & SKBEDIT_F_INHERITDSFIELD) {
int wlen = skb_network_offset(skb);
switch (skb_protocol(skb, true)) {
case htons(ETH_P_IP):
wlen += sizeof(struct iphdr);
if (!pskb_may_pull(skb, wlen))
goto err;
skb->priority = ipv4_get_dsfield(ip_hdr(skb)) >> 2;
break;
case htons(ETH_P_IPV6):
wlen += sizeof(struct ipv6hdr);
if (!pskb_may_pull(skb, wlen))
goto err;
skb->priority = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2;
break;
}
}
if (params->flags & SKBEDIT_F_QUEUE_MAPPING &&
skb->dev->real_num_tx_queues > params->queue_mapping) {
#ifdef CONFIG_NET_EGRESS
netdev_xmit_skip_txqueue(true);
#endif
skb_set_queue_mapping(skb, tcf_skbedit_hash(params, skb));
}
if (params->flags & SKBEDIT_F_MARK) {
skb->mark &= ~params->mask;
skb->mark |= params->mark & params->mask;
}
if (params->flags & SKBEDIT_F_PTYPE)
skb->pkt_type = params->ptype;
return action;
err:
qstats_drop_inc(this_cpu_ptr(d->common.cpu_qstats));
return TC_ACT_SHOT;
}
static void tcf_skbedit_stats_update(struct tc_action *a, u64 bytes,
u64 packets, u64 drops,
u64 lastuse, bool hw)
{
struct tcf_skbedit *d = to_skbedit(a);
struct tcf_t *tm = &d->tcf_tm;
tcf_action_update_stats(a, bytes, packets, drops, hw);
tm->lastuse = max_t(u64, tm->lastuse, lastuse);
}
static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
[TCA_SKBEDIT_PARMS] = { .len = sizeof(struct tc_skbedit) },
[TCA_SKBEDIT_PRIORITY] = { .len = sizeof(u32) },
[TCA_SKBEDIT_QUEUE_MAPPING] = { .len = sizeof(u16) },
[TCA_SKBEDIT_MARK] = { .len = sizeof(u32) },
[TCA_SKBEDIT_PTYPE] = { .len = sizeof(u16) },
[TCA_SKBEDIT_MASK] = { .len = sizeof(u32) },
[TCA_SKBEDIT_FLAGS] = { .len = sizeof(u64) },
[TCA_SKBEDIT_QUEUE_MAPPING_MAX] = { .len = sizeof(u16) },
};
static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
struct nlattr *est, struct tc_action **a,
struct tcf_proto *tp, u32 act_flags,
struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, act_skbedit_ops.net_id);
bool bind = act_flags & TCA_ACT_FLAGS_BIND;
struct tcf_skbedit_params *params_new;
struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
struct tcf_chain *goto_ch = NULL;
struct tc_skbedit *parm;
struct tcf_skbedit *d;
u32 flags = 0, *priority = NULL, *mark = NULL, *mask = NULL;
u16 *queue_mapping = NULL, *ptype = NULL;
u16 mapping_mod = 1;
bool exists = false;
int ret = 0, err;
u32 index;
if (nla == NULL)
return -EINVAL;
err = nla_parse_nested_deprecated(tb, TCA_SKBEDIT_MAX, nla,
skbedit_policy, NULL);
if (err < 0)
return err;
if (tb[TCA_SKBEDIT_PARMS] == NULL)
return -EINVAL;
if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
flags |= SKBEDIT_F_PRIORITY;
priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
}
if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
if (is_tcf_skbedit_ingress(act_flags) &&
!(act_flags & TCA_ACT_FLAGS_SKIP_SW)) {
NL_SET_ERR_MSG_MOD(extack, "\"queue_mapping\" option on receive side is hardware only, use skip_sw");
return -EOPNOTSUPP;
}
flags |= SKBEDIT_F_QUEUE_MAPPING;
queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
}
if (tb[TCA_SKBEDIT_PTYPE] != NULL) {
ptype = nla_data(tb[TCA_SKBEDIT_PTYPE]);
if (!skb_pkt_type_ok(*ptype))
return -EINVAL;
flags |= SKBEDIT_F_PTYPE;
}
if (tb[TCA_SKBEDIT_MARK] != NULL) {
flags |= SKBEDIT_F_MARK;
mark = nla_data(tb[TCA_SKBEDIT_MARK]);
}
if (tb[TCA_SKBEDIT_MASK] != NULL) {
flags |= SKBEDIT_F_MASK;
mask = nla_data(tb[TCA_SKBEDIT_MASK]);
}
if (tb[TCA_SKBEDIT_FLAGS] != NULL) {
u64 *pure_flags = nla_data(tb[TCA_SKBEDIT_FLAGS]);
if (*pure_flags & SKBEDIT_F_TXQ_SKBHASH) {
u16 *queue_mapping_max;
if (!tb[TCA_SKBEDIT_QUEUE_MAPPING] ||
!tb[TCA_SKBEDIT_QUEUE_MAPPING_MAX]) {
NL_SET_ERR_MSG_MOD(extack, "Missing required range of queue_mapping.");
return -EINVAL;
}
queue_mapping_max =
nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING_MAX]);
if (*queue_mapping_max < *queue_mapping) {
NL_SET_ERR_MSG_MOD(extack, "The range of queue_mapping is invalid, max < min.");
return -EINVAL;
}
mapping_mod = *queue_mapping_max - *queue_mapping + 1;
flags |= SKBEDIT_F_TXQ_SKBHASH;
}
if (*pure_flags & SKBEDIT_F_INHERITDSFIELD)
flags |= SKBEDIT_F_INHERITDSFIELD;
}
parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
index = parm->index;
err = tcf_idr_check_alloc(tn, &index, a, bind);
if (err < 0)
return err;
exists = err;
if (exists && bind)
return 0;
if (!flags) {
if (exists)
tcf_idr_release(*a, bind);
else
tcf_idr_cleanup(tn, index);
return -EINVAL;
}
if (!exists) {
ret = tcf_idr_create(tn, index, est, a,
&act_skbedit_ops, bind, true, act_flags);
if (ret) {
tcf_idr_cleanup(tn, index);
return ret;
}
d = to_skbedit(*a);
ret = ACT_P_CREATED;
} else {
d = to_skbedit(*a);
if (!(act_flags & TCA_ACT_FLAGS_REPLACE)) {
tcf_idr_release(*a, bind);
return -EEXIST;
}
}
err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
if (err < 0)
goto release_idr;
params_new = kzalloc(sizeof(*params_new), GFP_KERNEL);
if (unlikely(!params_new)) {
err = -ENOMEM;
goto put_chain;
}
params_new->flags = flags;
if (flags & SKBEDIT_F_PRIORITY)
params_new->priority = *priority;
if (flags & SKBEDIT_F_QUEUE_MAPPING) {
params_new->queue_mapping = *queue_mapping;
params_new->mapping_mod = mapping_mod;
}
if (flags & SKBEDIT_F_MARK)
params_new->mark = *mark;
if (flags & SKBEDIT_F_PTYPE)
params_new->ptype = *ptype;
/* default behaviour is to use all the bits */
params_new->mask = 0xffffffff;
if (flags & SKBEDIT_F_MASK)
params_new->mask = *mask;
spin_lock_bh(&d->tcf_lock);
goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
params_new = rcu_replace_pointer(d->params, params_new,
lockdep_is_held(&d->tcf_lock));
spin_unlock_bh(&d->tcf_lock);
if (params_new)
kfree_rcu(params_new, rcu);
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
return ret;
put_chain:
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
release_idr:
tcf_idr_release(*a, bind);
return err;
}
static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
int bind, int ref)
{
unsigned char *b = skb_tail_pointer(skb);
struct tcf_skbedit *d = to_skbedit(a);
struct tcf_skbedit_params *params;
struct tc_skbedit opt = {
.index = d->tcf_index,
.refcnt = refcount_read(&d->tcf_refcnt) - ref,
.bindcnt = atomic_read(&d->tcf_bindcnt) - bind,
};
u64 pure_flags = 0;
struct tcf_t t;
spin_lock_bh(&d->tcf_lock);
params = rcu_dereference_protected(d->params,
lockdep_is_held(&d->tcf_lock));
opt.action = d->tcf_action;
if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
goto nla_put_failure;
if ((params->flags & SKBEDIT_F_PRIORITY) &&
nla_put_u32(skb, TCA_SKBEDIT_PRIORITY, params->priority))
goto nla_put_failure;
if ((params->flags & SKBEDIT_F_QUEUE_MAPPING) &&
nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING, params->queue_mapping))
goto nla_put_failure;
if ((params->flags & SKBEDIT_F_MARK) &&
nla_put_u32(skb, TCA_SKBEDIT_MARK, params->mark))
goto nla_put_failure;
if ((params->flags & SKBEDIT_F_PTYPE) &&
nla_put_u16(skb, TCA_SKBEDIT_PTYPE, params->ptype))
goto nla_put_failure;
if ((params->flags & SKBEDIT_F_MASK) &&
nla_put_u32(skb, TCA_SKBEDIT_MASK, params->mask))
goto nla_put_failure;
if (params->flags & SKBEDIT_F_INHERITDSFIELD)
pure_flags |= SKBEDIT_F_INHERITDSFIELD;
if (params->flags & SKBEDIT_F_TXQ_SKBHASH) {
if (nla_put_u16(skb, TCA_SKBEDIT_QUEUE_MAPPING_MAX,
params->queue_mapping + params->mapping_mod - 1))
goto nla_put_failure;
pure_flags |= SKBEDIT_F_TXQ_SKBHASH;
}
if (pure_flags != 0 &&
nla_put(skb, TCA_SKBEDIT_FLAGS, sizeof(pure_flags), &pure_flags))
goto nla_put_failure;
tcf_tm_dump(&t, &d->tcf_tm);
if (nla_put_64bit(skb, TCA_SKBEDIT_TM, sizeof(t), &t, TCA_SKBEDIT_PAD))
goto nla_put_failure;
spin_unlock_bh(&d->tcf_lock);
return skb->len;
nla_put_failure:
spin_unlock_bh(&d->tcf_lock);
nlmsg_trim(skb, b);
return -1;
}
static void tcf_skbedit_cleanup(struct tc_action *a)
{
struct tcf_skbedit *d = to_skbedit(a);
struct tcf_skbedit_params *params;
params = rcu_dereference_protected(d->params, 1);
if (params)
kfree_rcu(params, rcu);
}
static size_t tcf_skbedit_get_fill_size(const struct tc_action *act)
{
return nla_total_size(sizeof(struct tc_skbedit))
+ nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_PRIORITY */
+ nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_QUEUE_MAPPING */
+ nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_QUEUE_MAPPING_MAX */
+ nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_MARK */
+ nla_total_size(sizeof(u16)) /* TCA_SKBEDIT_PTYPE */
+ nla_total_size(sizeof(u32)) /* TCA_SKBEDIT_MASK */
+ nla_total_size_64bit(sizeof(u64)); /* TCA_SKBEDIT_FLAGS */
}
static int tcf_skbedit_offload_act_setup(struct tc_action *act, void *entry_data,
u32 *index_inc, bool bind,
struct netlink_ext_ack *extack)
{
if (bind) {
struct flow_action_entry *entry = entry_data;
if (is_tcf_skbedit_mark(act)) {
entry->id = FLOW_ACTION_MARK;
entry->mark = tcf_skbedit_mark(act);
} else if (is_tcf_skbedit_ptype(act)) {
entry->id = FLOW_ACTION_PTYPE;
entry->ptype = tcf_skbedit_ptype(act);
} else if (is_tcf_skbedit_priority(act)) {
entry->id = FLOW_ACTION_PRIORITY;
entry->priority = tcf_skbedit_priority(act);
} else if (is_tcf_skbedit_tx_queue_mapping(act)) {
NL_SET_ERR_MSG_MOD(extack, "Offload not supported when \"queue_mapping\" option is used on transmit side");
return -EOPNOTSUPP;
} else if (is_tcf_skbedit_rx_queue_mapping(act)) {
entry->id = FLOW_ACTION_RX_QUEUE_MAPPING;
entry->rx_queue = tcf_skbedit_rx_queue_mapping(act);
} else if (is_tcf_skbedit_inheritdsfield(act)) {
NL_SET_ERR_MSG_MOD(extack, "Offload not supported when \"inheritdsfield\" option is used");
return -EOPNOTSUPP;
} else {
NL_SET_ERR_MSG_MOD(extack, "Unsupported skbedit option offload");
return -EOPNOTSUPP;
}
*index_inc = 1;
} else {
struct flow_offload_action *fl_action = entry_data;
if (is_tcf_skbedit_mark(act))
fl_action->id = FLOW_ACTION_MARK;
else if (is_tcf_skbedit_ptype(act))
fl_action->id = FLOW_ACTION_PTYPE;
else if (is_tcf_skbedit_priority(act))
fl_action->id = FLOW_ACTION_PRIORITY;
else if (is_tcf_skbedit_rx_queue_mapping(act))
fl_action->id = FLOW_ACTION_RX_QUEUE_MAPPING;
else
return -EOPNOTSUPP;
}
return 0;
}
static struct tc_action_ops act_skbedit_ops = {
.kind = "skbedit",
.id = TCA_ID_SKBEDIT,
.owner = THIS_MODULE,
.act = tcf_skbedit_act,
.stats_update = tcf_skbedit_stats_update,
.dump = tcf_skbedit_dump,
.init = tcf_skbedit_init,
.cleanup = tcf_skbedit_cleanup,
.get_fill_size = tcf_skbedit_get_fill_size,
.offload_act_setup = tcf_skbedit_offload_act_setup,
.size = sizeof(struct tcf_skbedit),
};
static __net_init int skbedit_init_net(struct net *net)
{
struct tc_action_net *tn = net_generic(net, act_skbedit_ops.net_id);
return tc_action_net_init(net, tn, &act_skbedit_ops);
}
static void __net_exit skbedit_exit_net(struct list_head *net_list)
{
tc_action_net_exit(net_list, act_skbedit_ops.net_id);
}
static struct pernet_operations skbedit_net_ops = {
.init = skbedit_init_net,
.exit_batch = skbedit_exit_net,
.id = &act_skbedit_ops.net_id,
.size = sizeof(struct tc_action_net),
};
MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
MODULE_DESCRIPTION("SKB Editing");
MODULE_LICENSE("GPL");
static int __init skbedit_init_module(void)
{
return tcf_register_action(&act_skbedit_ops, &skbedit_net_ops);
}
static void __exit skbedit_cleanup_module(void)
{
tcf_unregister_action(&act_skbedit_ops, &skbedit_net_ops);
}
module_init(skbedit_init_module);
module_exit(skbedit_cleanup_module);