diff options
Diffstat (limited to 'net/sched/cls_u32.c')
| -rw-r--r-- | net/sched/cls_u32.c | 1490 |
1 files changed, 1490 insertions, 0 deletions
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c new file mode 100644 index 000000000..04448bfb4 --- /dev/null +++ b/net/sched/cls_u32.c @@ -0,0 +1,1490 @@ +// 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> + +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; + int 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; + int 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; +} + +static 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; + + root_ht->refcnt++; + 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; + } + 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)); + } + + tp_c->refcnt++; + RCU_INIT_POINTER(root_ht->next, tp_c->hlist); + rcu_assign_pointer(tp_c->hlist, root_ht); + + root_ht->refcnt++; + 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 && --ht->refcnt == 0) + 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; + + WARN_ON(--ht->refcnt); + + 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 && --root_ht->refcnt == 1) + u32_destroy_hnode(tp, root_ht, extack); + + if (--tp_c->refcnt == 0) { + 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 (--ht->refcnt == 0) + 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 (ht->refcnt == 1) { + u32_destroy_hnode(tp, ht, extack); + } else { + NL_SET_ERR_MSG_MOD(extack, "Can not delete in-use filter"); + return -EBUSY; + } + +out: + *last = 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; + } + ht_down->refcnt++; + } + + ht_old = rtnl_dereference(n->ht_down); + rcu_assign_pointer(n->ht_down, ht_down); + + if (ht_old) + 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) + 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) + 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; + } + } + 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, +}; + +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_LICENSE("GPL"); |