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kernel-aes67/net/sched/cls_u32.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* net/sched/cls_u32.c Ugly (or Universal) 32bit key Packet Classifier.
*
* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
* The filters are packed to hash tables of key nodes
* with a set of 32bit key/mask pairs at every node.
* Nodes reference next level hash tables etc.
*
* This scheme is the best universal classifier I managed to
* invent; it is not super-fast, but it is not slow (provided you
* program it correctly), and general enough. And its relative
* speed grows as the number of rules becomes larger.
*
* It seems that it represents the best middle point between
* speed and manageability both by human and by machine.
*
* It is especially useful for link sharing combined with QoS;
* pure RSVP doesn't need such a general approach and can use
* much simpler (and faster) schemes, sort of cls_rsvp.c.
*
* nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/percpu.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <linux/bitmap.h>
#include <linux/netdevice.h>
#include <linux/hash.h>
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>
#include <linux/idr.h>
#include <net/tc_wrapper.h>
struct tc_u_knode {
struct tc_u_knode __rcu *next;
u32 handle;
struct tc_u_hnode __rcu *ht_up;
struct tcf_exts exts;
int ifindex;
u8 fshift;
struct tcf_result res;
struct tc_u_hnode __rcu *ht_down;
#ifdef CONFIG_CLS_U32_PERF
struct tc_u32_pcnt __percpu *pf;
#endif
u32 flags;
unsigned int in_hw_count;
#ifdef CONFIG_CLS_U32_MARK
u32 val;
u32 mask;
u32 __percpu *pcpu_success;
#endif
struct rcu_work rwork;
/* The 'sel' field MUST be the last field in structure to allow for
* tc_u32_keys allocated at end of structure.
*/
struct tc_u32_sel sel;
};
struct tc_u_hnode {
struct tc_u_hnode __rcu *next;
u32 handle;
u32 prio;
refcount_t refcnt;
unsigned int divisor;
struct idr handle_idr;
bool is_root;
struct rcu_head rcu;
u32 flags;
/* The 'ht' field MUST be the last field in structure to allow for
* more entries allocated at end of structure.
*/
struct tc_u_knode __rcu *ht[];
};
struct tc_u_common {
struct tc_u_hnode __rcu *hlist;
void *ptr;
refcount_t refcnt;
struct idr handle_idr;
struct hlist_node hnode;
long knodes;
};
static inline unsigned int u32_hash_fold(__be32 key,
const struct tc_u32_sel *sel,
u8 fshift)
{
unsigned int h = ntohl(key & sel->hmask) >> fshift;
return h;
}
TC_INDIRECT_SCOPE int u32_classify(struct sk_buff *skb,
const struct tcf_proto *tp,
struct tcf_result *res)
{
struct {
struct tc_u_knode *knode;
unsigned int off;
} stack[TC_U32_MAXDEPTH];
struct tc_u_hnode *ht = rcu_dereference_bh(tp->root);
unsigned int off = skb_network_offset(skb);
struct tc_u_knode *n;
int sdepth = 0;
int off2 = 0;
int sel = 0;
#ifdef CONFIG_CLS_U32_PERF
int j;
#endif
int i, r;
next_ht:
n = rcu_dereference_bh(ht->ht[sel]);
next_knode:
if (n) {
struct tc_u32_key *key = n->sel.keys;
#ifdef CONFIG_CLS_U32_PERF
__this_cpu_inc(n->pf->rcnt);
j = 0;
#endif
if (tc_skip_sw(n->flags)) {
n = rcu_dereference_bh(n->next);
goto next_knode;
}
#ifdef CONFIG_CLS_U32_MARK
if ((skb->mark & n->mask) != n->val) {
n = rcu_dereference_bh(n->next);
goto next_knode;
} else {
__this_cpu_inc(*n->pcpu_success);
}
#endif
for (i = n->sel.nkeys; i > 0; i--, key++) {
int toff = off + key->off + (off2 & key->offmask);
__be32 *data, hdata;
if (skb_headroom(skb) + toff > INT_MAX)
goto out;
data = skb_header_pointer(skb, toff, 4, &hdata);
if (!data)
goto out;
if ((*data ^ key->val) & key->mask) {
n = rcu_dereference_bh(n->next);
goto next_knode;
}
#ifdef CONFIG_CLS_U32_PERF
__this_cpu_inc(n->pf->kcnts[j]);
j++;
#endif
}
ht = rcu_dereference_bh(n->ht_down);
if (!ht) {
check_terminal:
if (n->sel.flags & TC_U32_TERMINAL) {
*res = n->res;
if (!tcf_match_indev(skb, n->ifindex)) {
n = rcu_dereference_bh(n->next);
goto next_knode;
}
#ifdef CONFIG_CLS_U32_PERF
__this_cpu_inc(n->pf->rhit);
#endif
r = tcf_exts_exec(skb, &n->exts, res);
if (r < 0) {
n = rcu_dereference_bh(n->next);
goto next_knode;
}
return r;
}
n = rcu_dereference_bh(n->next);
goto next_knode;
}
/* PUSH */
if (sdepth >= TC_U32_MAXDEPTH)
goto deadloop;
stack[sdepth].knode = n;
stack[sdepth].off = off;
sdepth++;
ht = rcu_dereference_bh(n->ht_down);
sel = 0;
if (ht->divisor) {
__be32 *data, hdata;
data = skb_header_pointer(skb, off + n->sel.hoff, 4,
&hdata);
if (!data)
goto out;
sel = ht->divisor & u32_hash_fold(*data, &n->sel,
n->fshift);
}
if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
goto next_ht;
if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
off2 = n->sel.off + 3;
if (n->sel.flags & TC_U32_VAROFFSET) {
__be16 *data, hdata;
data = skb_header_pointer(skb,
off + n->sel.offoff,
2, &hdata);
if (!data)
goto out;
off2 += ntohs(n->sel.offmask & *data) >>
n->sel.offshift;
}
off2 &= ~3;
}
if (n->sel.flags & TC_U32_EAT) {
off += off2;
off2 = 0;
}
if (off < skb->len)
goto next_ht;
}
/* POP */
if (sdepth--) {
n = stack[sdepth].knode;
ht = rcu_dereference_bh(n->ht_up);
off = stack[sdepth].off;
goto check_terminal;
}
out:
return -1;
deadloop:
net_warn_ratelimited("cls_u32: dead loop\n");
return -1;
}
static struct tc_u_hnode *u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
{
struct tc_u_hnode *ht;
for (ht = rtnl_dereference(tp_c->hlist);
ht;
ht = rtnl_dereference(ht->next))
if (ht->handle == handle)
break;
return ht;
}
static struct tc_u_knode *u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
{
unsigned int sel;
struct tc_u_knode *n = NULL;
sel = TC_U32_HASH(handle);
if (sel > ht->divisor)
goto out;
for (n = rtnl_dereference(ht->ht[sel]);
n;
n = rtnl_dereference(n->next))
if (n->handle == handle)
break;
out:
return n;
}
static void *u32_get(struct tcf_proto *tp, u32 handle)
{
struct tc_u_hnode *ht;
struct tc_u_common *tp_c = tp->data;
if (TC_U32_HTID(handle) == TC_U32_ROOT)
ht = rtnl_dereference(tp->root);
else
ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
if (!ht)
return NULL;
if (TC_U32_KEY(handle) == 0)
return ht;
return u32_lookup_key(ht, handle);
}
/* Protected by rtnl lock */
static u32 gen_new_htid(struct tc_u_common *tp_c, struct tc_u_hnode *ptr)
{
int id = idr_alloc_cyclic(&tp_c->handle_idr, ptr, 1, 0x7FF, GFP_KERNEL);
if (id < 0)
return 0;
return (id | 0x800U) << 20;
}
static struct hlist_head *tc_u_common_hash;
#define U32_HASH_SHIFT 10
#define U32_HASH_SIZE (1 << U32_HASH_SHIFT)
static void *tc_u_common_ptr(const struct tcf_proto *tp)
{
struct tcf_block *block = tp->chain->block;
/* The block sharing is currently supported only
* for classless qdiscs. In that case we use block
* for tc_u_common identification. In case the
* block is not shared, block->q is a valid pointer
* and we can use that. That works for classful qdiscs.
*/
if (tcf_block_shared(block))
return block;
else
return block->q;
}
static struct hlist_head *tc_u_hash(void *key)
{
return tc_u_common_hash + hash_ptr(key, U32_HASH_SHIFT);
}
static struct tc_u_common *tc_u_common_find(void *key)
{
struct tc_u_common *tc;
hlist_for_each_entry(tc, tc_u_hash(key), hnode) {
if (tc->ptr == key)
return tc;
}
return NULL;
}
static int u32_init(struct tcf_proto *tp)
{
struct tc_u_hnode *root_ht;
void *key = tc_u_common_ptr(tp);
struct tc_u_common *tp_c = tc_u_common_find(key);
root_ht = kzalloc(struct_size(root_ht, ht, 1), GFP_KERNEL);
if (root_ht == NULL)
return -ENOBUFS;
refcount_set(&root_ht->refcnt, 1);
root_ht->handle = tp_c ? gen_new_htid(tp_c, root_ht) : 0x80000000;
root_ht->prio = tp->prio;
root_ht->is_root = true;
idr_init(&root_ht->handle_idr);
if (tp_c == NULL) {
tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
if (tp_c == NULL) {
kfree(root_ht);
return -ENOBUFS;
}
refcount_set(&tp_c->refcnt, 1);
tp_c->ptr = key;
INIT_HLIST_NODE(&tp_c->hnode);
idr_init(&tp_c->handle_idr);
hlist_add_head(&tp_c->hnode, tc_u_hash(key));
} else {
refcount_inc(&tp_c->refcnt);
}
RCU_INIT_POINTER(root_ht->next, tp_c->hlist);
rcu_assign_pointer(tp_c->hlist, root_ht);
/* root_ht must be destroyed when tcf_proto is destroyed */
rcu_assign_pointer(tp->root, root_ht);
tp->data = tp_c;
return 0;
}
static void __u32_destroy_key(struct tc_u_knode *n)
{
struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
tcf_exts_destroy(&n->exts);
if (ht && refcount_dec_and_test(&ht->refcnt))
kfree(ht);
kfree(n);
}
static void u32_destroy_key(struct tc_u_knode *n, bool free_pf)
{
tcf_exts_put_net(&n->exts);
#ifdef CONFIG_CLS_U32_PERF
if (free_pf)
free_percpu(n->pf);
#endif
#ifdef CONFIG_CLS_U32_MARK
if (free_pf)
free_percpu(n->pcpu_success);
#endif
__u32_destroy_key(n);
}
/* u32_delete_key_rcu should be called when free'ing a copied
* version of a tc_u_knode obtained from u32_init_knode(). When
* copies are obtained from u32_init_knode() the statistics are
* shared between the old and new copies to allow readers to
* continue to update the statistics during the copy. To support
* this the u32_delete_key_rcu variant does not free the percpu
* statistics.
*/
static void u32_delete_key_work(struct work_struct *work)
{
struct tc_u_knode *key = container_of(to_rcu_work(work),
struct tc_u_knode,
rwork);
rtnl_lock();
u32_destroy_key(key, false);
rtnl_unlock();
}
/* u32_delete_key_freepf_rcu is the rcu callback variant
* that free's the entire structure including the statistics
* percpu variables. Only use this if the key is not a copy
* returned by u32_init_knode(). See u32_delete_key_rcu()
* for the variant that should be used with keys return from
* u32_init_knode()
*/
static void u32_delete_key_freepf_work(struct work_struct *work)
{
struct tc_u_knode *key = container_of(to_rcu_work(work),
struct tc_u_knode,
rwork);
rtnl_lock();
u32_destroy_key(key, true);
rtnl_unlock();
}
static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_knode __rcu **kp;
struct tc_u_knode *pkp;
struct tc_u_hnode *ht = rtnl_dereference(key->ht_up);
if (ht) {
kp = &ht->ht[TC_U32_HASH(key->handle)];
for (pkp = rtnl_dereference(*kp); pkp;
kp = &pkp->next, pkp = rtnl_dereference(*kp)) {
if (pkp == key) {
RCU_INIT_POINTER(*kp, key->next);
tp_c->knodes--;
tcf_unbind_filter(tp, &key->res);
idr_remove(&ht->handle_idr, key->handle);
tcf_exts_get_net(&key->exts);
tcf_queue_work(&key->rwork, u32_delete_key_freepf_work);
return 0;
}
}
}
WARN_ON(1);
return 0;
}
static void u32_clear_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
struct netlink_ext_ack *extack)
{
struct tcf_block *block = tp->chain->block;
struct tc_cls_u32_offload cls_u32 = {};
tc_cls_common_offload_init(&cls_u32.common, tp, h->flags, extack);
cls_u32.command = TC_CLSU32_DELETE_HNODE;
cls_u32.hnode.divisor = h->divisor;
cls_u32.hnode.handle = h->handle;
cls_u32.hnode.prio = h->prio;
tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, false, true);
}
static int u32_replace_hw_hnode(struct tcf_proto *tp, struct tc_u_hnode *h,
u32 flags, struct netlink_ext_ack *extack)
{
struct tcf_block *block = tp->chain->block;
struct tc_cls_u32_offload cls_u32 = {};
bool skip_sw = tc_skip_sw(flags);
bool offloaded = false;
int err;
tc_cls_common_offload_init(&cls_u32.common, tp, flags, extack);
cls_u32.command = TC_CLSU32_NEW_HNODE;
cls_u32.hnode.divisor = h->divisor;
cls_u32.hnode.handle = h->handle;
cls_u32.hnode.prio = h->prio;
err = tc_setup_cb_call(block, TC_SETUP_CLSU32, &cls_u32, skip_sw, true);
if (err < 0) {
u32_clear_hw_hnode(tp, h, NULL);
return err;
} else if (err > 0) {
offloaded = true;
}
if (skip_sw && !offloaded)
return -EINVAL;
return 0;
}
static void u32_remove_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
struct netlink_ext_ack *extack)
{
struct tcf_block *block = tp->chain->block;
struct tc_cls_u32_offload cls_u32 = {};
tc_cls_common_offload_init(&cls_u32.common, tp, n->flags, extack);
cls_u32.command = TC_CLSU32_DELETE_KNODE;
cls_u32.knode.handle = n->handle;
tc_setup_cb_destroy(block, tp, TC_SETUP_CLSU32, &cls_u32, false,
&n->flags, &n->in_hw_count, true);
}
static int u32_replace_hw_knode(struct tcf_proto *tp, struct tc_u_knode *n,
u32 flags, struct netlink_ext_ack *extack)
{
struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
struct tcf_block *block = tp->chain->block;
struct tc_cls_u32_offload cls_u32 = {};
bool skip_sw = tc_skip_sw(flags);
int err;
tc_cls_common_offload_init(&cls_u32.common, tp, flags, extack);
cls_u32.command = TC_CLSU32_REPLACE_KNODE;
cls_u32.knode.handle = n->handle;
cls_u32.knode.fshift = n->fshift;
#ifdef CONFIG_CLS_U32_MARK
cls_u32.knode.val = n->val;
cls_u32.knode.mask = n->mask;
#else
cls_u32.knode.val = 0;
cls_u32.knode.mask = 0;
#endif
cls_u32.knode.sel = &n->sel;
cls_u32.knode.res = &n->res;
cls_u32.knode.exts = &n->exts;
if (n->ht_down)
cls_u32.knode.link_handle = ht->handle;
err = tc_setup_cb_add(block, tp, TC_SETUP_CLSU32, &cls_u32, skip_sw,
&n->flags, &n->in_hw_count, true);
if (err) {
u32_remove_hw_knode(tp, n, NULL);
return err;
}
if (skip_sw && !(n->flags & TCA_CLS_FLAGS_IN_HW))
return -EINVAL;
return 0;
}
static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
struct netlink_ext_ack *extack)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_knode *n;
unsigned int h;
for (h = 0; h <= ht->divisor; h++) {
while ((n = rtnl_dereference(ht->ht[h])) != NULL) {
RCU_INIT_POINTER(ht->ht[h],
rtnl_dereference(n->next));
tp_c->knodes--;
tcf_unbind_filter(tp, &n->res);
u32_remove_hw_knode(tp, n, extack);
idr_remove(&ht->handle_idr, n->handle);
if (tcf_exts_get_net(&n->exts))
tcf_queue_work(&n->rwork, u32_delete_key_freepf_work);
else
u32_destroy_key(n, true);
}
}
}
static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
struct netlink_ext_ack *extack)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode __rcu **hn;
struct tc_u_hnode *phn;
u32_clear_hnode(tp, ht, extack);
hn = &tp_c->hlist;
for (phn = rtnl_dereference(*hn);
phn;
hn = &phn->next, phn = rtnl_dereference(*hn)) {
if (phn == ht) {
u32_clear_hw_hnode(tp, ht, extack);
idr_destroy(&ht->handle_idr);
idr_remove(&tp_c->handle_idr, ht->handle);
RCU_INIT_POINTER(*hn, ht->next);
kfree_rcu(ht, rcu);
return 0;
}
}
return -ENOENT;
}
static void u32_destroy(struct tcf_proto *tp, bool rtnl_held,
struct netlink_ext_ack *extack)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *root_ht = rtnl_dereference(tp->root);
WARN_ON(root_ht == NULL);
if (root_ht && refcount_dec_and_test(&root_ht->refcnt))
u32_destroy_hnode(tp, root_ht, extack);
if (refcount_dec_and_test(&tp_c->refcnt)) {
struct tc_u_hnode *ht;
hlist_del(&tp_c->hnode);
while ((ht = rtnl_dereference(tp_c->hlist)) != NULL) {
u32_clear_hnode(tp, ht, extack);
RCU_INIT_POINTER(tp_c->hlist, ht->next);
/* u32_destroy_key() will later free ht for us, if it's
* still referenced by some knode
*/
if (refcount_dec_and_test(&ht->refcnt))
kfree_rcu(ht, rcu);
}
idr_destroy(&tp_c->handle_idr);
kfree(tp_c);
}
tp->data = NULL;
}
static int u32_delete(struct tcf_proto *tp, void *arg, bool *last,
bool rtnl_held, struct netlink_ext_ack *extack)
{
struct tc_u_hnode *ht = arg;
struct tc_u_common *tp_c = tp->data;
int ret = 0;
if (TC_U32_KEY(ht->handle)) {
u32_remove_hw_knode(tp, (struct tc_u_knode *)ht, extack);
ret = u32_delete_key(tp, (struct tc_u_knode *)ht);
goto out;
}
if (ht->is_root) {
NL_SET_ERR_MSG_MOD(extack, "Not allowed to delete root node");
return -EINVAL;
}
if (refcount_dec_if_one(&ht->refcnt)) {
u32_destroy_hnode(tp, ht, extack);
} else {
NL_SET_ERR_MSG_MOD(extack, "Can not delete in-use filter");
return -EBUSY;
}
out:
*last = refcount_read(&tp_c->refcnt) == 1 && tp_c->knodes == 0;
return ret;
}
static u32 gen_new_kid(struct tc_u_hnode *ht, u32 htid)
{
u32 index = htid | 0x800;
u32 max = htid | 0xFFF;
if (idr_alloc_u32(&ht->handle_idr, NULL, &index, max, GFP_KERNEL)) {
index = htid + 1;
if (idr_alloc_u32(&ht->handle_idr, NULL, &index, max,
GFP_KERNEL))
index = max;
}
return index;
}
static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
[TCA_U32_CLASSID] = { .type = NLA_U32 },
[TCA_U32_HASH] = { .type = NLA_U32 },
[TCA_U32_LINK] = { .type = NLA_U32 },
[TCA_U32_DIVISOR] = { .type = NLA_U32 },
[TCA_U32_SEL] = { .len = sizeof(struct tc_u32_sel) },
[TCA_U32_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ },
[TCA_U32_MARK] = { .len = sizeof(struct tc_u32_mark) },
[TCA_U32_FLAGS] = { .type = NLA_U32 },
};
static void u32_unbind_filter(struct tcf_proto *tp, struct tc_u_knode *n,
struct nlattr **tb)
{
if (tb[TCA_U32_CLASSID])
tcf_unbind_filter(tp, &n->res);
}
static void u32_bind_filter(struct tcf_proto *tp, struct tc_u_knode *n,
unsigned long base, struct nlattr **tb)
{
if (tb[TCA_U32_CLASSID]) {
n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
tcf_bind_filter(tp, &n->res, base);
}
}
static int u32_set_parms(struct net *net, struct tcf_proto *tp,
struct tc_u_knode *n, struct nlattr **tb,
struct nlattr *est, u32 flags, u32 fl_flags,
struct netlink_ext_ack *extack)
{
int err, ifindex = -1;
err = tcf_exts_validate_ex(net, tp, tb, est, &n->exts, flags,
fl_flags, extack);
if (err < 0)
return err;
if (tb[TCA_U32_INDEV]) {
ifindex = tcf_change_indev(net, tb[TCA_U32_INDEV], extack);
if (ifindex < 0)
return -EINVAL;
}
if (tb[TCA_U32_LINK]) {
u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
struct tc_u_hnode *ht_down = NULL, *ht_old;
if (TC_U32_KEY(handle)) {
NL_SET_ERR_MSG_MOD(extack, "u32 Link handle must be a hash table");
return -EINVAL;
}
if (handle) {
ht_down = u32_lookup_ht(tp->data, handle);
if (!ht_down) {
NL_SET_ERR_MSG_MOD(extack, "Link hash table not found");
return -EINVAL;
}
if (ht_down->is_root) {
NL_SET_ERR_MSG_MOD(extack, "Not linking to root node");
return -EINVAL;
}
refcount_inc(&ht_down->refcnt);
}
ht_old = rtnl_dereference(n->ht_down);
rcu_assign_pointer(n->ht_down, ht_down);
if (ht_old)
refcount_dec(&ht_old->refcnt);
}
if (ifindex >= 0)
n->ifindex = ifindex;
return 0;
}
static void u32_replace_knode(struct tcf_proto *tp, struct tc_u_common *tp_c,
struct tc_u_knode *n)
{
struct tc_u_knode __rcu **ins;
struct tc_u_knode *pins;
struct tc_u_hnode *ht;
if (TC_U32_HTID(n->handle) == TC_U32_ROOT)
ht = rtnl_dereference(tp->root);
else
ht = u32_lookup_ht(tp_c, TC_U32_HTID(n->handle));
ins = &ht->ht[TC_U32_HASH(n->handle)];
/* The node must always exist for it to be replaced if this is not the
* case then something went very wrong elsewhere.
*/
for (pins = rtnl_dereference(*ins); ;
ins = &pins->next, pins = rtnl_dereference(*ins))
if (pins->handle == n->handle)
break;
idr_replace(&ht->handle_idr, n, n->handle);
RCU_INIT_POINTER(n->next, pins->next);
rcu_assign_pointer(*ins, n);
}
static struct tc_u_knode *u32_init_knode(struct net *net, struct tcf_proto *tp,
struct tc_u_knode *n)
{
struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
struct tc_u32_sel *s = &n->sel;
struct tc_u_knode *new;
new = kzalloc(struct_size(new, sel.keys, s->nkeys), GFP_KERNEL);
if (!new)
return NULL;
RCU_INIT_POINTER(new->next, n->next);
new->handle = n->handle;
RCU_INIT_POINTER(new->ht_up, n->ht_up);
new->ifindex = n->ifindex;
new->fshift = n->fshift;
new->flags = n->flags;
RCU_INIT_POINTER(new->ht_down, ht);
#ifdef CONFIG_CLS_U32_PERF
/* Statistics may be incremented by readers during update
* so we must keep them in tact. When the node is later destroyed
* a special destroy call must be made to not free the pf memory.
*/
new->pf = n->pf;
#endif
#ifdef CONFIG_CLS_U32_MARK
new->val = n->val;
new->mask = n->mask;
/* Similarly success statistics must be moved as pointers */
new->pcpu_success = n->pcpu_success;
#endif
memcpy(&new->sel, s, struct_size(s, keys, s->nkeys));
if (tcf_exts_init(&new->exts, net, TCA_U32_ACT, TCA_U32_POLICE)) {
kfree(new);
return NULL;
}
/* bump reference count as long as we hold pointer to structure */
if (ht)
refcount_inc(&ht->refcnt);
return new;
}
static int u32_change(struct net *net, struct sk_buff *in_skb,
struct tcf_proto *tp, unsigned long base, u32 handle,
struct nlattr **tca, void **arg, u32 flags,
struct netlink_ext_ack *extack)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *ht;
struct tc_u_knode *n;
struct tc_u32_sel *s;
struct nlattr *opt = tca[TCA_OPTIONS];
struct nlattr *tb[TCA_U32_MAX + 1];
u32 htid, userflags = 0;
size_t sel_size;
int err;
if (!opt) {
if (handle) {
NL_SET_ERR_MSG_MOD(extack, "Filter handle requires options");
return -EINVAL;
} else {
return 0;
}
}
err = nla_parse_nested_deprecated(tb, TCA_U32_MAX, opt, u32_policy,
extack);
if (err < 0)
return err;
if (tb[TCA_U32_FLAGS]) {
userflags = nla_get_u32(tb[TCA_U32_FLAGS]);
if (!tc_flags_valid(userflags)) {
NL_SET_ERR_MSG_MOD(extack, "Invalid filter flags");
return -EINVAL;
}
}
n = *arg;
if (n) {
struct tc_u_knode *new;
if (TC_U32_KEY(n->handle) == 0) {
NL_SET_ERR_MSG_MOD(extack, "Key node id cannot be zero");
return -EINVAL;
}
if ((n->flags ^ userflags) &
~(TCA_CLS_FLAGS_IN_HW | TCA_CLS_FLAGS_NOT_IN_HW)) {
NL_SET_ERR_MSG_MOD(extack, "Key node flags do not match passed flags");
return -EINVAL;
}
new = u32_init_knode(net, tp, n);
if (!new)
return -ENOMEM;
err = u32_set_parms(net, tp, new, tb, tca[TCA_RATE],
flags, new->flags, extack);
if (err) {
__u32_destroy_key(new);
return err;
}
u32_bind_filter(tp, new, base, tb);
err = u32_replace_hw_knode(tp, new, flags, extack);
if (err) {
u32_unbind_filter(tp, new, tb);
if (tb[TCA_U32_LINK]) {
struct tc_u_hnode *ht_old;
ht_old = rtnl_dereference(n->ht_down);
if (ht_old)
refcount_inc(&ht_old->refcnt);
}
__u32_destroy_key(new);
return err;
}
if (!tc_in_hw(new->flags))
new->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
u32_replace_knode(tp, tp_c, new);
tcf_unbind_filter(tp, &n->res);
tcf_exts_get_net(&n->exts);
tcf_queue_work(&n->rwork, u32_delete_key_work);
return 0;
}
if (tb[TCA_U32_DIVISOR]) {
unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
if (!is_power_of_2(divisor)) {
NL_SET_ERR_MSG_MOD(extack, "Divisor is not a power of 2");
return -EINVAL;
}
if (divisor-- > 0x100) {
NL_SET_ERR_MSG_MOD(extack, "Exceeded maximum 256 hash buckets");
return -EINVAL;
}
if (TC_U32_KEY(handle)) {
NL_SET_ERR_MSG_MOD(extack, "Divisor can only be used on a hash table");
return -EINVAL;
}
ht = kzalloc(struct_size(ht, ht, divisor + 1), GFP_KERNEL);
if (ht == NULL)
return -ENOBUFS;
if (handle == 0) {
handle = gen_new_htid(tp->data, ht);
if (handle == 0) {
kfree(ht);
return -ENOMEM;
}
} else {
err = idr_alloc_u32(&tp_c->handle_idr, ht, &handle,
handle, GFP_KERNEL);
if (err) {
kfree(ht);
return err;
}
}
refcount_set(&ht->refcnt, 1);
ht->divisor = divisor;
ht->handle = handle;
ht->prio = tp->prio;
idr_init(&ht->handle_idr);
ht->flags = userflags;
err = u32_replace_hw_hnode(tp, ht, userflags, extack);
if (err) {
idr_remove(&tp_c->handle_idr, handle);
kfree(ht);
return err;
}
RCU_INIT_POINTER(ht->next, tp_c->hlist);
rcu_assign_pointer(tp_c->hlist, ht);
*arg = ht;
return 0;
}
if (tb[TCA_U32_HASH]) {
htid = nla_get_u32(tb[TCA_U32_HASH]);
if (TC_U32_HTID(htid) == TC_U32_ROOT) {
ht = rtnl_dereference(tp->root);
htid = ht->handle;
} else {
ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
if (!ht) {
NL_SET_ERR_MSG_MOD(extack, "Specified hash table not found");
return -EINVAL;
}
}
} else {
ht = rtnl_dereference(tp->root);
htid = ht->handle;
}
if (ht->divisor < TC_U32_HASH(htid)) {
NL_SET_ERR_MSG_MOD(extack, "Specified hash table buckets exceed configured value");
return -EINVAL;
}
/* At this point, we need to derive the new handle that will be used to
* uniquely map the identity of this table match entry. The
* identity of the entry that we need to construct is 32 bits made of:
* htid(12b):bucketid(8b):node/entryid(12b)
*
* At this point _we have the table(ht)_ in which we will insert this
* entry. We carry the table's id in variable "htid".
* Note that earlier code picked the ht selection either by a) the user
* providing the htid specified via TCA_U32_HASH attribute or b) when
* no such attribute is passed then the root ht, is default to at ID
* 0x[800][00][000]. Rule: the root table has a single bucket with ID 0.
* If OTOH the user passed us the htid, they may also pass a bucketid of
* choice. 0 is fine. For example a user htid is 0x[600][01][000] it is
* indicating hash bucketid of 1. Rule: the entry/node ID _cannot_ be
* passed via the htid, so even if it was non-zero it will be ignored.
*
* We may also have a handle, if the user passed one. The handle also
* carries the same addressing of htid(12b):bucketid(8b):node/entryid(12b).
* Rule: the bucketid on the handle is ignored even if one was passed;
* rather the value on "htid" is always assumed to be the bucketid.
*/
if (handle) {
/* Rule: The htid from handle and tableid from htid must match */
if (TC_U32_HTID(handle) && TC_U32_HTID(handle ^ htid)) {
NL_SET_ERR_MSG_MOD(extack, "Handle specified hash table address mismatch");
return -EINVAL;
}
/* Ok, so far we have a valid htid(12b):bucketid(8b) but we
* need to finalize the table entry identification with the last
* part - the node/entryid(12b)). Rule: Nodeid _cannot be 0_ for
* entries. Rule: nodeid of 0 is reserved only for tables(see
* earlier code which processes TC_U32_DIVISOR attribute).
* Rule: The nodeid can only be derived from the handle (and not
* htid).
* Rule: if the handle specified zero for the node id example
* 0x60000000, then pick a new nodeid from the pool of IDs
* this hash table has been allocating from.
* If OTOH it is specified (i.e for example the user passed a
* handle such as 0x60000123), then we use it generate our final
* handle which is used to uniquely identify the match entry.
*/
if (!TC_U32_NODE(handle)) {
handle = gen_new_kid(ht, htid);
} else {
handle = htid | TC_U32_NODE(handle);
err = idr_alloc_u32(&ht->handle_idr, NULL, &handle,
handle, GFP_KERNEL);
if (err)
return err;
}
} else {
/* The user did not give us a handle; lets just generate one
* from the table's pool of nodeids.
*/
handle = gen_new_kid(ht, htid);
}
if (tb[TCA_U32_SEL] == NULL) {
NL_SET_ERR_MSG_MOD(extack, "Selector not specified");
err = -EINVAL;
goto erridr;
}
s = nla_data(tb[TCA_U32_SEL]);
sel_size = struct_size(s, keys, s->nkeys);
if (nla_len(tb[TCA_U32_SEL]) < sel_size) {
err = -EINVAL;
goto erridr;
}
n = kzalloc(struct_size(n, sel.keys, s->nkeys), GFP_KERNEL);
if (n == NULL) {
err = -ENOBUFS;
goto erridr;
}
#ifdef CONFIG_CLS_U32_PERF
n->pf = __alloc_percpu(struct_size(n->pf, kcnts, s->nkeys),
__alignof__(struct tc_u32_pcnt));
if (!n->pf) {
err = -ENOBUFS;
goto errfree;
}
#endif
unsafe_memcpy(&n->sel, s, sel_size,
/* A composite flex-array structure destination,
* which was correctly sized with struct_size(),
* bounds-checked against nla_len(), and allocated
* above. */);
RCU_INIT_POINTER(n->ht_up, ht);
n->handle = handle;
n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
n->flags = userflags;
err = tcf_exts_init(&n->exts, net, TCA_U32_ACT, TCA_U32_POLICE);
if (err < 0)
goto errout;
#ifdef CONFIG_CLS_U32_MARK
n->pcpu_success = alloc_percpu(u32);
if (!n->pcpu_success) {
err = -ENOMEM;
goto errout;
}
if (tb[TCA_U32_MARK]) {
struct tc_u32_mark *mark;
mark = nla_data(tb[TCA_U32_MARK]);
n->val = mark->val;
n->mask = mark->mask;
}
#endif
err = u32_set_parms(net, tp, n, tb, tca[TCA_RATE],
flags, n->flags, extack);
u32_bind_filter(tp, n, base, tb);
if (err == 0) {
struct tc_u_knode __rcu **ins;
struct tc_u_knode *pins;
err = u32_replace_hw_knode(tp, n, flags, extack);
if (err)
goto errunbind;
if (!tc_in_hw(n->flags))
n->flags |= TCA_CLS_FLAGS_NOT_IN_HW;
ins = &ht->ht[TC_U32_HASH(handle)];
for (pins = rtnl_dereference(*ins); pins;
ins = &pins->next, pins = rtnl_dereference(*ins))
if (TC_U32_NODE(handle) < TC_U32_NODE(pins->handle))
break;
RCU_INIT_POINTER(n->next, pins);
rcu_assign_pointer(*ins, n);
tp_c->knodes++;
*arg = n;
return 0;
}
errunbind:
u32_unbind_filter(tp, n, tb);
#ifdef CONFIG_CLS_U32_MARK
free_percpu(n->pcpu_success);
#endif
errout:
tcf_exts_destroy(&n->exts);
#ifdef CONFIG_CLS_U32_PERF
errfree:
free_percpu(n->pf);
#endif
kfree(n);
erridr:
idr_remove(&ht->handle_idr, handle);
return err;
}
static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg,
bool rtnl_held)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *ht;
struct tc_u_knode *n;
unsigned int h;
if (arg->stop)
return;
for (ht = rtnl_dereference(tp_c->hlist);
ht;
ht = rtnl_dereference(ht->next)) {
if (ht->prio != tp->prio)
continue;
if (!tc_cls_stats_dump(tp, arg, ht))
return;
for (h = 0; h <= ht->divisor; h++) {
for (n = rtnl_dereference(ht->ht[h]);
n;
n = rtnl_dereference(n->next)) {
if (!tc_cls_stats_dump(tp, arg, n))
return;
}
}
}
}
static int u32_reoffload_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht,
bool add, flow_setup_cb_t *cb, void *cb_priv,
struct netlink_ext_ack *extack)
{
struct tc_cls_u32_offload cls_u32 = {};
int err;
tc_cls_common_offload_init(&cls_u32.common, tp, ht->flags, extack);
cls_u32.command = add ? TC_CLSU32_NEW_HNODE : TC_CLSU32_DELETE_HNODE;
cls_u32.hnode.divisor = ht->divisor;
cls_u32.hnode.handle = ht->handle;
cls_u32.hnode.prio = ht->prio;
err = cb(TC_SETUP_CLSU32, &cls_u32, cb_priv);
if (err && add && tc_skip_sw(ht->flags))
return err;
return 0;
}
static int u32_reoffload_knode(struct tcf_proto *tp, struct tc_u_knode *n,
bool add, flow_setup_cb_t *cb, void *cb_priv,
struct netlink_ext_ack *extack)
{
struct tc_u_hnode *ht = rtnl_dereference(n->ht_down);
struct tcf_block *block = tp->chain->block;
struct tc_cls_u32_offload cls_u32 = {};
tc_cls_common_offload_init(&cls_u32.common, tp, n->flags, extack);
cls_u32.command = add ?
TC_CLSU32_REPLACE_KNODE : TC_CLSU32_DELETE_KNODE;
cls_u32.knode.handle = n->handle;
if (add) {
cls_u32.knode.fshift = n->fshift;
#ifdef CONFIG_CLS_U32_MARK
cls_u32.knode.val = n->val;
cls_u32.knode.mask = n->mask;
#else
cls_u32.knode.val = 0;
cls_u32.knode.mask = 0;
#endif
cls_u32.knode.sel = &n->sel;
cls_u32.knode.res = &n->res;
cls_u32.knode.exts = &n->exts;
if (n->ht_down)
cls_u32.knode.link_handle = ht->handle;
}
return tc_setup_cb_reoffload(block, tp, add, cb, TC_SETUP_CLSU32,
&cls_u32, cb_priv, &n->flags,
&n->in_hw_count);
}
static int u32_reoffload(struct tcf_proto *tp, bool add, flow_setup_cb_t *cb,
void *cb_priv, struct netlink_ext_ack *extack)
{
struct tc_u_common *tp_c = tp->data;
struct tc_u_hnode *ht;
struct tc_u_knode *n;
unsigned int h;
int err;
for (ht = rtnl_dereference(tp_c->hlist);
ht;
ht = rtnl_dereference(ht->next)) {
if (ht->prio != tp->prio)
continue;
/* When adding filters to a new dev, try to offload the
* hashtable first. When removing, do the filters before the
* hashtable.
*/
if (add && !tc_skip_hw(ht->flags)) {
err = u32_reoffload_hnode(tp, ht, add, cb, cb_priv,
extack);
if (err)
return err;
}
for (h = 0; h <= ht->divisor; h++) {
for (n = rtnl_dereference(ht->ht[h]);
n;
n = rtnl_dereference(n->next)) {
if (tc_skip_hw(n->flags))
continue;
err = u32_reoffload_knode(tp, n, add, cb,
cb_priv, extack);
if (err)
return err;
}
}
if (!add && !tc_skip_hw(ht->flags))
u32_reoffload_hnode(tp, ht, add, cb, cb_priv, extack);
}
return 0;
}
static void u32_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
unsigned long base)
{
struct tc_u_knode *n = fh;
tc_cls_bind_class(classid, cl, q, &n->res, base);
}
static int u32_dump(struct net *net, struct tcf_proto *tp, void *fh,
struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
{
struct tc_u_knode *n = fh;
struct tc_u_hnode *ht_up, *ht_down;
struct nlattr *nest;
if (n == NULL)
return skb->len;
t->tcm_handle = n->handle;
nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
if (nest == NULL)
goto nla_put_failure;
if (TC_U32_KEY(n->handle) == 0) {
struct tc_u_hnode *ht = fh;
u32 divisor = ht->divisor + 1;
if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
goto nla_put_failure;
} else {
#ifdef CONFIG_CLS_U32_PERF
struct tc_u32_pcnt *gpf;
int cpu;
#endif
if (nla_put(skb, TCA_U32_SEL, struct_size(&n->sel, keys, n->sel.nkeys),
&n->sel))
goto nla_put_failure;
ht_up = rtnl_dereference(n->ht_up);
if (ht_up) {
u32 htid = n->handle & 0xFFFFF000;
if (nla_put_u32(skb, TCA_U32_HASH, htid))
goto nla_put_failure;
}
if (n->res.classid &&
nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
goto nla_put_failure;
ht_down = rtnl_dereference(n->ht_down);
if (ht_down &&
nla_put_u32(skb, TCA_U32_LINK, ht_down->handle))
goto nla_put_failure;
if (n->flags && nla_put_u32(skb, TCA_U32_FLAGS, n->flags))
goto nla_put_failure;
#ifdef CONFIG_CLS_U32_MARK
if ((n->val || n->mask)) {
struct tc_u32_mark mark = {.val = n->val,
.mask = n->mask,
.success = 0};
int cpum;
for_each_possible_cpu(cpum) {
__u32 cnt = *per_cpu_ptr(n->pcpu_success, cpum);
mark.success += cnt;
}
if (nla_put(skb, TCA_U32_MARK, sizeof(mark), &mark))
goto nla_put_failure;
}
#endif
if (tcf_exts_dump(skb, &n->exts) < 0)
goto nla_put_failure;
if (n->ifindex) {
struct net_device *dev;
dev = __dev_get_by_index(net, n->ifindex);
if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
goto nla_put_failure;
}
#ifdef CONFIG_CLS_U32_PERF
gpf = kzalloc(struct_size(gpf, kcnts, n->sel.nkeys), GFP_KERNEL);
if (!gpf)
goto nla_put_failure;
for_each_possible_cpu(cpu) {
int i;
struct tc_u32_pcnt *pf = per_cpu_ptr(n->pf, cpu);
gpf->rcnt += pf->rcnt;
gpf->rhit += pf->rhit;
for (i = 0; i < n->sel.nkeys; i++)
gpf->kcnts[i] += pf->kcnts[i];
}
if (nla_put_64bit(skb, TCA_U32_PCNT, struct_size(gpf, kcnts, n->sel.nkeys),
gpf, TCA_U32_PAD)) {
kfree(gpf);
goto nla_put_failure;
}
kfree(gpf);
#endif
}
nla_nest_end(skb, nest);
if (TC_U32_KEY(n->handle))
if (tcf_exts_dump_stats(skb, &n->exts) < 0)
goto nla_put_failure;
return skb->len;
nla_put_failure:
nla_nest_cancel(skb, nest);
return -1;
}
static struct tcf_proto_ops cls_u32_ops __read_mostly = {
.kind = "u32",
.classify = u32_classify,
.init = u32_init,
.destroy = u32_destroy,
.get = u32_get,
.change = u32_change,
.delete = u32_delete,
.walk = u32_walk,
.reoffload = u32_reoffload,
.dump = u32_dump,
.bind_class = u32_bind_class,
.owner = THIS_MODULE,
};
MODULE_ALIAS_NET_CLS("u32");
static int __init init_u32(void)
{
int i, ret;
pr_info("u32 classifier\n");
#ifdef CONFIG_CLS_U32_PERF
pr_info(" Performance counters on\n");
#endif
pr_info(" input device check on\n");
#ifdef CONFIG_NET_CLS_ACT
pr_info(" Actions configured\n");
#endif
tc_u_common_hash = kvmalloc_array(U32_HASH_SIZE,
sizeof(struct hlist_head),
GFP_KERNEL);
if (!tc_u_common_hash)
return -ENOMEM;
for (i = 0; i < U32_HASH_SIZE; i++)
INIT_HLIST_HEAD(&tc_u_common_hash[i]);
ret = register_tcf_proto_ops(&cls_u32_ops);
if (ret)
kvfree(tc_u_common_hash);
return ret;
}
static void __exit exit_u32(void)
{
unregister_tcf_proto_ops(&cls_u32_ops);
kvfree(tc_u_common_hash);
}
module_init(init_u32)
module_exit(exit_u32)
MODULE_DESCRIPTION("Universal 32bit based TC Classifier");
MODULE_LICENSE("GPL");
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