#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/skbuff.h>
#include <linux/rtnetlink.h>
#include <linux/module.h>
#include <linux/init.h>
#include <net/netlink.h>
#include <net/pkt_sched.h>
#include <net/pkt_cls.h>
#include <linux/tc_act/tc_gact.h>
#include <net/tc_act/tc_gact.h>
#include <net/tc_wrapper.h>
static struct tc_action_ops act_gact_ops;
#ifdef CONFIG_GACT_PROB
static int gact_net_rand(struct tcf_gact *gact)
{
smp_rmb();
if (get_random_u32_below(gact->tcfg_pval))
return gact->tcf_action;
return gact->tcfg_paction;
}
static int gact_determ(struct tcf_gact *gact)
{
u32 pack = atomic_inc_return(&gact->packets);
smp_rmb();
if (pack % gact->tcfg_pval)
return gact->tcf_action;
return gact->tcfg_paction;
}
typedef int (*g_rand)(struct tcf_gact *gact);
static g_rand gact_rand[MAX_RAND] = { NULL, gact_net_rand, gact_determ };
#endif
static const struct nla_policy gact_policy[TCA_GACT_MAX + 1] = {
[TCA_GACT_PARMS] = { .len = sizeof(struct tc_gact) },
[TCA_GACT_PROB] = { .len = sizeof(struct tc_gact_p) },
};
static int tcf_gact_init(struct net *net, struct nlattr *nla,
struct nlattr *est, struct tc_action **a,
struct tcf_proto *tp, u32 flags,
struct netlink_ext_ack *extack)
{
struct tc_action_net *tn = net_generic(net, act_gact_ops.net_id);
bool bind = flags & TCA_ACT_FLAGS_BIND;
struct nlattr *tb[TCA_GACT_MAX + 1];
struct tcf_chain *goto_ch = NULL;
struct tc_gact *parm;
struct tcf_gact *gact;
int ret = 0;
u32 index;
int err;
#ifdef CONFIG_GACT_PROB
struct tc_gact_p *p_parm = NULL;
#endif
if (nla == NULL)
return -EINVAL;
err = nla_parse_nested_deprecated(tb, TCA_GACT_MAX, nla, gact_policy,
NULL);
if (err < 0)
return err;
if (tb[TCA_GACT_PARMS] == NULL)
return -EINVAL;
parm = nla_data(tb[TCA_GACT_PARMS]);
index = parm->index;
#ifndef CONFIG_GACT_PROB
if (tb[TCA_GACT_PROB] != NULL)
return -EOPNOTSUPP;
#else
if (tb[TCA_GACT_PROB]) {
p_parm = nla_data(tb[TCA_GACT_PROB]);
if (p_parm->ptype >= MAX_RAND)
return -EINVAL;
if (TC_ACT_EXT_CMP(p_parm->paction, TC_ACT_GOTO_CHAIN)) {
NL_SET_ERR_MSG(extack,
"goto chain not allowed on fallback");
return -EINVAL;
}
}
#endif
err = tcf_idr_check_alloc(tn, &index, a, bind);
if (!err) {
ret = tcf_idr_create_from_flags(tn, index, est, a,
&act_gact_ops, bind, flags);
if (ret) {
tcf_idr_cleanup(tn, index);
return ret;
}
ret = ACT_P_CREATED;
} else if (err > 0) {
if (bind)
return ACT_P_BOUND;
if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
tcf_idr_release(*a, bind);
return -EEXIST;
}
} else {
return err;
}
err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
if (err < 0)
goto release_idr;
gact = to_gact(*a);
spin_lock_bh(&gact->tcf_lock);
goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
#ifdef CONFIG_GACT_PROB
if (p_parm) {
gact->tcfg_paction = p_parm->paction;
gact->tcfg_pval = max_t(u16, 1, p_parm->pval);
smp_wmb();
gact->tcfg_ptype = p_parm->ptype;
}
#endif
spin_unlock_bh(&gact->tcf_lock);
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
return ret;
release_idr:
tcf_idr_release(*a, bind);
return err;
}
TC_INDIRECT_SCOPE int tcf_gact_act(struct sk_buff *skb,
const struct tc_action *a,
struct tcf_result *res)
{
struct tcf_gact *gact = to_gact(a);
int action = READ_ONCE(gact->tcf_action);
#ifdef CONFIG_GACT_PROB
{
u32 ptype = READ_ONCE(gact->tcfg_ptype);
if (ptype)
action = gact_rand[ptype](gact);
}
#endif
tcf_action_update_bstats(&gact->common, skb);
if (action == TC_ACT_SHOT)
tcf_action_inc_drop_qstats(&gact->common);
tcf_lastuse_update(&gact->tcf_tm);
return action;
}
static void tcf_gact_stats_update(struct tc_action *a, u64 bytes, u64 packets,
u64 drops, u64 lastuse, bool hw)
{
struct tcf_gact *gact = to_gact(a);
int action = READ_ONCE(gact->tcf_action);
struct tcf_t *tm = &gact->tcf_tm;
tcf_action_update_stats(a, bytes, packets,
action == TC_ACT_SHOT ? packets : drops, hw);
tm->lastuse = max_t(u64, tm->lastuse, lastuse);
}
static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a,
int bind, int ref)
{
unsigned char *b = skb_tail_pointer(skb);
struct tcf_gact *gact = to_gact(a);
struct tc_gact opt = {
.index = gact->tcf_index,
.refcnt = refcount_read(&gact->tcf_refcnt) - ref,
.bindcnt = atomic_read(&gact->tcf_bindcnt) - bind,
};
struct tcf_t t;
spin_lock_bh(&gact->tcf_lock);
opt.action = gact->tcf_action;
if (nla_put(skb, TCA_GACT_PARMS, sizeof(opt), &opt))
goto nla_put_failure;
#ifdef CONFIG_GACT_PROB
if (gact->tcfg_ptype) {
struct tc_gact_p p_opt = {
.paction = gact->tcfg_paction,
.pval = gact->tcfg_pval,
.ptype = gact->tcfg_ptype,
};
if (nla_put(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt))
goto nla_put_failure;
}
#endif
tcf_tm_dump(&t, &gact->tcf_tm);
if (nla_put_64bit(skb, TCA_GACT_TM, sizeof(t), &t, TCA_GACT_PAD))
goto nla_put_failure;
spin_unlock_bh(&gact->tcf_lock);
return skb->len;
nla_put_failure:
spin_unlock_bh(&gact->tcf_lock);
nlmsg_trim(skb, b);
return -1;
}
static size_t tcf_gact_get_fill_size(const struct tc_action *act)
{
size_t sz = nla_total_size(sizeof(struct tc_gact));
#ifdef CONFIG_GACT_PROB
if (to_gact(act)->tcfg_ptype)
sz += nla_total_size(sizeof(struct tc_gact_p));
#endif
return sz;
}
static int tcf_gact_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_gact_ok(act)) {
entry->id = FLOW_ACTION_ACCEPT;
} else if (is_tcf_gact_shot(act)) {
entry->id = FLOW_ACTION_DROP;
} else if (is_tcf_gact_trap(act)) {
entry->id = FLOW_ACTION_TRAP;
} else if (is_tcf_gact_goto_chain(act)) {
entry->id = FLOW_ACTION_GOTO;
entry->chain_index = tcf_gact_goto_chain_index(act);
} else if (is_tcf_gact_continue(act)) {
NL_SET_ERR_MSG_MOD(extack, "Offload of \"continue\" action is not supported");
return -EOPNOTSUPP;
} else if (is_tcf_gact_reclassify(act)) {
NL_SET_ERR_MSG_MOD(extack, "Offload of \"reclassify\" action is not supported");
return -EOPNOTSUPP;
} else if (is_tcf_gact_pipe(act)) {
NL_SET_ERR_MSG_MOD(extack, "Offload of \"pipe\" action is not supported");
return -EOPNOTSUPP;
} else {
NL_SET_ERR_MSG_MOD(extack, "Unsupported generic action offload");
return -EOPNOTSUPP;
}
*index_inc = 1;
} else {
struct flow_offload_action *fl_action = entry_data;
if (is_tcf_gact_ok(act))
fl_action->id = FLOW_ACTION_ACCEPT;
else if (is_tcf_gact_shot(act))
fl_action->id = FLOW_ACTION_DROP;
else if (is_tcf_gact_trap(act))
fl_action->id = FLOW_ACTION_TRAP;
else if (is_tcf_gact_goto_chain(act))
fl_action->id = FLOW_ACTION_GOTO;
else
return -EOPNOTSUPP;
}
return 0;
}
static struct tc_action_ops act_gact_ops = {
.kind = "gact",
.id = TCA_ID_GACT,
.owner = THIS_MODULE,
.act = tcf_gact_act,
.stats_update = tcf_gact_stats_update,
.dump = tcf_gact_dump,
.init = tcf_gact_init,
.get_fill_size = tcf_gact_get_fill_size,
.offload_act_setup = tcf_gact_offload_act_setup,
.size = sizeof(struct tcf_gact),
};
MODULE_ALIAS_NET_ACT("gact");
static __net_init int gact_init_net(struct net *net)
{
struct tc_action_net *tn = net_generic(net, act_gact_ops.net_id);
return tc_action_net_init(net, tn, &act_gact_ops);
}
static void __net_exit gact_exit_net(struct list_head *net_list)
{
tc_action_net_exit(net_list, act_gact_ops.net_id);
}
static struct pernet_operations gact_net_ops = {
.init = gact_init_net,
.exit_batch = gact_exit_net,
.id = &act_gact_ops.net_id,
.size = sizeof(struct tc_action_net),
};
MODULE_AUTHOR("Jamal Hadi Salim(2002-4)");
MODULE_DESCRIPTION("Generic Classifier actions");
MODULE_LICENSE("GPL");
static int __init gact_init_module(void)
{
#ifdef CONFIG_GACT_PROB
pr_info("GACT probability on\n");
#else
pr_info("GACT probability NOT on\n");
#endif
return tcf_register_action(&act_gact_ops, &gact_net_ops);
}
static void __exit gact_cleanup_module(void)
{
tcf_unregister_action(&act_gact_ops, &gact_net_ops);
}
module_init(gact_init_module);
module_exit(gact_cleanup_module);
