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-rw-r--r--net/sched/cls_route.c692
1 files changed, 692 insertions, 0 deletions
diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
new file mode 100644
index 000000000..1ad4b3e60
--- /dev/null
+++ b/net/sched/cls_route.c
@@ -0,0 +1,692 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * net/sched/cls_route.c ROUTE4 classifier.
+ *
+ * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ */
+
+#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/skbuff.h>
+#include <net/dst.h>
+#include <net/route.h>
+#include <net/netlink.h>
+#include <net/act_api.h>
+#include <net/pkt_cls.h>
+
+/*
+ * 1. For now we assume that route tags < 256.
+ * It allows to use direct table lookups, instead of hash tables.
+ * 2. For now we assume that "from TAG" and "fromdev DEV" statements
+ * are mutually exclusive.
+ * 3. "to TAG from ANY" has higher priority, than "to ANY from XXX"
+ */
+struct route4_fastmap {
+ struct route4_filter *filter;
+ u32 id;
+ int iif;
+};
+
+struct route4_head {
+ struct route4_fastmap fastmap[16];
+ struct route4_bucket __rcu *table[256 + 1];
+ struct rcu_head rcu;
+};
+
+struct route4_bucket {
+ /* 16 FROM buckets + 16 IIF buckets + 1 wildcard bucket */
+ struct route4_filter __rcu *ht[16 + 16 + 1];
+ struct rcu_head rcu;
+};
+
+struct route4_filter {
+ struct route4_filter __rcu *next;
+ u32 id;
+ int iif;
+
+ struct tcf_result res;
+ struct tcf_exts exts;
+ u32 handle;
+ struct route4_bucket *bkt;
+ struct tcf_proto *tp;
+ struct rcu_work rwork;
+};
+
+#define ROUTE4_FAILURE ((struct route4_filter *)(-1L))
+
+static inline int route4_fastmap_hash(u32 id, int iif)
+{
+ return id & 0xF;
+}
+
+static DEFINE_SPINLOCK(fastmap_lock);
+static void
+route4_reset_fastmap(struct route4_head *head)
+{
+ spin_lock_bh(&fastmap_lock);
+ memset(head->fastmap, 0, sizeof(head->fastmap));
+ spin_unlock_bh(&fastmap_lock);
+}
+
+static void
+route4_set_fastmap(struct route4_head *head, u32 id, int iif,
+ struct route4_filter *f)
+{
+ int h = route4_fastmap_hash(id, iif);
+
+ /* fastmap updates must look atomic to aling id, iff, filter */
+ spin_lock_bh(&fastmap_lock);
+ head->fastmap[h].id = id;
+ head->fastmap[h].iif = iif;
+ head->fastmap[h].filter = f;
+ spin_unlock_bh(&fastmap_lock);
+}
+
+static inline int route4_hash_to(u32 id)
+{
+ return id & 0xFF;
+}
+
+static inline int route4_hash_from(u32 id)
+{
+ return (id >> 16) & 0xF;
+}
+
+static inline int route4_hash_iif(int iif)
+{
+ return 16 + ((iif >> 16) & 0xF);
+}
+
+static inline int route4_hash_wild(void)
+{
+ return 32;
+}
+
+#define ROUTE4_APPLY_RESULT() \
+{ \
+ *res = f->res; \
+ if (tcf_exts_has_actions(&f->exts)) { \
+ int r = tcf_exts_exec(skb, &f->exts, res); \
+ if (r < 0) { \
+ dont_cache = 1; \
+ continue; \
+ } \
+ return r; \
+ } else if (!dont_cache) \
+ route4_set_fastmap(head, id, iif, f); \
+ return 0; \
+}
+
+static int route4_classify(struct sk_buff *skb, const struct tcf_proto *tp,
+ struct tcf_result *res)
+{
+ struct route4_head *head = rcu_dereference_bh(tp->root);
+ struct dst_entry *dst;
+ struct route4_bucket *b;
+ struct route4_filter *f;
+ u32 id, h;
+ int iif, dont_cache = 0;
+
+ dst = skb_dst(skb);
+ if (!dst)
+ goto failure;
+
+ id = dst->tclassid;
+
+ iif = inet_iif(skb);
+
+ h = route4_fastmap_hash(id, iif);
+
+ spin_lock(&fastmap_lock);
+ if (id == head->fastmap[h].id &&
+ iif == head->fastmap[h].iif &&
+ (f = head->fastmap[h].filter) != NULL) {
+ if (f == ROUTE4_FAILURE) {
+ spin_unlock(&fastmap_lock);
+ goto failure;
+ }
+
+ *res = f->res;
+ spin_unlock(&fastmap_lock);
+ return 0;
+ }
+ spin_unlock(&fastmap_lock);
+
+ h = route4_hash_to(id);
+
+restart:
+ b = rcu_dereference_bh(head->table[h]);
+ if (b) {
+ for (f = rcu_dereference_bh(b->ht[route4_hash_from(id)]);
+ f;
+ f = rcu_dereference_bh(f->next))
+ if (f->id == id)
+ ROUTE4_APPLY_RESULT();
+
+ for (f = rcu_dereference_bh(b->ht[route4_hash_iif(iif)]);
+ f;
+ f = rcu_dereference_bh(f->next))
+ if (f->iif == iif)
+ ROUTE4_APPLY_RESULT();
+
+ for (f = rcu_dereference_bh(b->ht[route4_hash_wild()]);
+ f;
+ f = rcu_dereference_bh(f->next))
+ ROUTE4_APPLY_RESULT();
+ }
+ if (h < 256) {
+ h = 256;
+ id &= ~0xFFFF;
+ goto restart;
+ }
+
+ if (!dont_cache)
+ route4_set_fastmap(head, id, iif, ROUTE4_FAILURE);
+failure:
+ return -1;
+}
+
+static inline u32 to_hash(u32 id)
+{
+ u32 h = id & 0xFF;
+
+ if (id & 0x8000)
+ h += 256;
+ return h;
+}
+
+static inline u32 from_hash(u32 id)
+{
+ id &= 0xFFFF;
+ if (id == 0xFFFF)
+ return 32;
+ if (!(id & 0x8000)) {
+ if (id > 255)
+ return 256;
+ return id & 0xF;
+ }
+ return 16 + (id & 0xF);
+}
+
+static void *route4_get(struct tcf_proto *tp, u32 handle)
+{
+ struct route4_head *head = rtnl_dereference(tp->root);
+ struct route4_bucket *b;
+ struct route4_filter *f;
+ unsigned int h1, h2;
+
+ h1 = to_hash(handle);
+ if (h1 > 256)
+ return NULL;
+
+ h2 = from_hash(handle >> 16);
+ if (h2 > 32)
+ return NULL;
+
+ b = rtnl_dereference(head->table[h1]);
+ if (b) {
+ for (f = rtnl_dereference(b->ht[h2]);
+ f;
+ f = rtnl_dereference(f->next))
+ if (f->handle == handle)
+ return f;
+ }
+ return NULL;
+}
+
+static int route4_init(struct tcf_proto *tp)
+{
+ struct route4_head *head;
+
+ head = kzalloc(sizeof(struct route4_head), GFP_KERNEL);
+ if (head == NULL)
+ return -ENOBUFS;
+
+ rcu_assign_pointer(tp->root, head);
+ return 0;
+}
+
+static void __route4_delete_filter(struct route4_filter *f)
+{
+ tcf_exts_destroy(&f->exts);
+ tcf_exts_put_net(&f->exts);
+ kfree(f);
+}
+
+static void route4_delete_filter_work(struct work_struct *work)
+{
+ struct route4_filter *f = container_of(to_rcu_work(work),
+ struct route4_filter,
+ rwork);
+ rtnl_lock();
+ __route4_delete_filter(f);
+ rtnl_unlock();
+}
+
+static void route4_queue_work(struct route4_filter *f)
+{
+ tcf_queue_work(&f->rwork, route4_delete_filter_work);
+}
+
+static void route4_destroy(struct tcf_proto *tp, bool rtnl_held,
+ struct netlink_ext_ack *extack)
+{
+ struct route4_head *head = rtnl_dereference(tp->root);
+ int h1, h2;
+
+ if (head == NULL)
+ return;
+
+ for (h1 = 0; h1 <= 256; h1++) {
+ struct route4_bucket *b;
+
+ b = rtnl_dereference(head->table[h1]);
+ if (b) {
+ for (h2 = 0; h2 <= 32; h2++) {
+ struct route4_filter *f;
+
+ while ((f = rtnl_dereference(b->ht[h2])) != NULL) {
+ struct route4_filter *next;
+
+ next = rtnl_dereference(f->next);
+ RCU_INIT_POINTER(b->ht[h2], next);
+ tcf_unbind_filter(tp, &f->res);
+ if (tcf_exts_get_net(&f->exts))
+ route4_queue_work(f);
+ else
+ __route4_delete_filter(f);
+ }
+ }
+ RCU_INIT_POINTER(head->table[h1], NULL);
+ kfree_rcu(b, rcu);
+ }
+ }
+ kfree_rcu(head, rcu);
+}
+
+static int route4_delete(struct tcf_proto *tp, void *arg, bool *last,
+ bool rtnl_held, struct netlink_ext_ack *extack)
+{
+ struct route4_head *head = rtnl_dereference(tp->root);
+ struct route4_filter *f = arg;
+ struct route4_filter __rcu **fp;
+ struct route4_filter *nf;
+ struct route4_bucket *b;
+ unsigned int h = 0;
+ int i, h1;
+
+ if (!head || !f)
+ return -EINVAL;
+
+ h = f->handle;
+ b = f->bkt;
+
+ fp = &b->ht[from_hash(h >> 16)];
+ for (nf = rtnl_dereference(*fp); nf;
+ fp = &nf->next, nf = rtnl_dereference(*fp)) {
+ if (nf == f) {
+ /* unlink it */
+ RCU_INIT_POINTER(*fp, rtnl_dereference(f->next));
+
+ /* Remove any fastmap lookups that might ref filter
+ * notice we unlink'd the filter so we can't get it
+ * back in the fastmap.
+ */
+ route4_reset_fastmap(head);
+
+ /* Delete it */
+ tcf_unbind_filter(tp, &f->res);
+ tcf_exts_get_net(&f->exts);
+ tcf_queue_work(&f->rwork, route4_delete_filter_work);
+
+ /* Strip RTNL protected tree */
+ for (i = 0; i <= 32; i++) {
+ struct route4_filter *rt;
+
+ rt = rtnl_dereference(b->ht[i]);
+ if (rt)
+ goto out;
+ }
+
+ /* OK, session has no flows */
+ RCU_INIT_POINTER(head->table[to_hash(h)], NULL);
+ kfree_rcu(b, rcu);
+ break;
+ }
+ }
+
+out:
+ *last = true;
+ for (h1 = 0; h1 <= 256; h1++) {
+ if (rcu_access_pointer(head->table[h1])) {
+ *last = false;
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static const struct nla_policy route4_policy[TCA_ROUTE4_MAX + 1] = {
+ [TCA_ROUTE4_CLASSID] = { .type = NLA_U32 },
+ [TCA_ROUTE4_TO] = { .type = NLA_U32 },
+ [TCA_ROUTE4_FROM] = { .type = NLA_U32 },
+ [TCA_ROUTE4_IIF] = { .type = NLA_U32 },
+};
+
+static int route4_set_parms(struct net *net, struct tcf_proto *tp,
+ unsigned long base, struct route4_filter *f,
+ u32 handle, struct route4_head *head,
+ struct nlattr **tb, struct nlattr *est, int new,
+ bool ovr, struct netlink_ext_ack *extack)
+{
+ u32 id = 0, to = 0, nhandle = 0x8000;
+ struct route4_filter *fp;
+ unsigned int h1;
+ struct route4_bucket *b;
+ int err;
+
+ err = tcf_exts_validate(net, tp, tb, est, &f->exts, ovr, true, extack);
+ if (err < 0)
+ return err;
+
+ if (tb[TCA_ROUTE4_TO]) {
+ if (new && handle & 0x8000)
+ return -EINVAL;
+ to = nla_get_u32(tb[TCA_ROUTE4_TO]);
+ if (to > 0xFF)
+ return -EINVAL;
+ nhandle = to;
+ }
+
+ if (tb[TCA_ROUTE4_FROM]) {
+ if (tb[TCA_ROUTE4_IIF])
+ return -EINVAL;
+ id = nla_get_u32(tb[TCA_ROUTE4_FROM]);
+ if (id > 0xFF)
+ return -EINVAL;
+ nhandle |= id << 16;
+ } else if (tb[TCA_ROUTE4_IIF]) {
+ id = nla_get_u32(tb[TCA_ROUTE4_IIF]);
+ if (id > 0x7FFF)
+ return -EINVAL;
+ nhandle |= (id | 0x8000) << 16;
+ } else
+ nhandle |= 0xFFFF << 16;
+
+ if (handle && new) {
+ nhandle |= handle & 0x7F00;
+ if (nhandle != handle)
+ return -EINVAL;
+ }
+
+ if (!nhandle) {
+ NL_SET_ERR_MSG(extack, "Replacing with handle of 0 is invalid");
+ return -EINVAL;
+ }
+
+ h1 = to_hash(nhandle);
+ b = rtnl_dereference(head->table[h1]);
+ if (!b) {
+ b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL);
+ if (b == NULL)
+ return -ENOBUFS;
+
+ rcu_assign_pointer(head->table[h1], b);
+ } else {
+ unsigned int h2 = from_hash(nhandle >> 16);
+
+ for (fp = rtnl_dereference(b->ht[h2]);
+ fp;
+ fp = rtnl_dereference(fp->next))
+ if (fp->handle == f->handle)
+ return -EEXIST;
+ }
+
+ if (tb[TCA_ROUTE4_TO])
+ f->id = to;
+
+ if (tb[TCA_ROUTE4_FROM])
+ f->id = to | id<<16;
+ else if (tb[TCA_ROUTE4_IIF])
+ f->iif = id;
+
+ f->handle = nhandle;
+ f->bkt = b;
+ f->tp = tp;
+
+ if (tb[TCA_ROUTE4_CLASSID]) {
+ f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]);
+ tcf_bind_filter(tp, &f->res, base);
+ }
+
+ return 0;
+}
+
+static int route4_change(struct net *net, struct sk_buff *in_skb,
+ struct tcf_proto *tp, unsigned long base, u32 handle,
+ struct nlattr **tca, void **arg, bool ovr,
+ bool rtnl_held, struct netlink_ext_ack *extack)
+{
+ struct route4_head *head = rtnl_dereference(tp->root);
+ struct route4_filter __rcu **fp;
+ struct route4_filter *fold, *f1, *pfp, *f = NULL;
+ struct route4_bucket *b;
+ struct nlattr *opt = tca[TCA_OPTIONS];
+ struct nlattr *tb[TCA_ROUTE4_MAX + 1];
+ unsigned int h, th;
+ int err;
+ bool new = true;
+
+ if (!handle) {
+ NL_SET_ERR_MSG(extack, "Creating with handle of 0 is invalid");
+ return -EINVAL;
+ }
+
+ if (opt == NULL)
+ return handle ? -EINVAL : 0;
+
+ err = nla_parse_nested_deprecated(tb, TCA_ROUTE4_MAX, opt,
+ route4_policy, NULL);
+ if (err < 0)
+ return err;
+
+ fold = *arg;
+ if (fold && handle && fold->handle != handle)
+ return -EINVAL;
+
+ err = -ENOBUFS;
+ f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL);
+ if (!f)
+ goto errout;
+
+ err = tcf_exts_init(&f->exts, net, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE);
+ if (err < 0)
+ goto errout;
+
+ if (fold) {
+ f->id = fold->id;
+ f->iif = fold->iif;
+ f->handle = fold->handle;
+
+ f->tp = fold->tp;
+ f->bkt = fold->bkt;
+ new = false;
+ }
+
+ err = route4_set_parms(net, tp, base, f, handle, head, tb,
+ tca[TCA_RATE], new, ovr, extack);
+ if (err < 0)
+ goto errout;
+
+ h = from_hash(f->handle >> 16);
+ fp = &f->bkt->ht[h];
+ for (pfp = rtnl_dereference(*fp);
+ (f1 = rtnl_dereference(*fp)) != NULL;
+ fp = &f1->next)
+ if (f->handle < f1->handle)
+ break;
+
+ tcf_block_netif_keep_dst(tp->chain->block);
+ rcu_assign_pointer(f->next, f1);
+ rcu_assign_pointer(*fp, f);
+
+ if (fold) {
+ th = to_hash(fold->handle);
+ h = from_hash(fold->handle >> 16);
+ b = rtnl_dereference(head->table[th]);
+ if (b) {
+ fp = &b->ht[h];
+ for (pfp = rtnl_dereference(*fp); pfp;
+ fp = &pfp->next, pfp = rtnl_dereference(*fp)) {
+ if (pfp == fold) {
+ rcu_assign_pointer(*fp, fold->next);
+ break;
+ }
+ }
+ }
+ }
+
+ route4_reset_fastmap(head);
+ *arg = f;
+ if (fold) {
+ tcf_unbind_filter(tp, &fold->res);
+ tcf_exts_get_net(&fold->exts);
+ tcf_queue_work(&fold->rwork, route4_delete_filter_work);
+ }
+ return 0;
+
+errout:
+ if (f)
+ tcf_exts_destroy(&f->exts);
+ kfree(f);
+ return err;
+}
+
+static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg,
+ bool rtnl_held)
+{
+ struct route4_head *head = rtnl_dereference(tp->root);
+ unsigned int h, h1;
+
+ if (head == NULL || arg->stop)
+ return;
+
+ for (h = 0; h <= 256; h++) {
+ struct route4_bucket *b = rtnl_dereference(head->table[h]);
+
+ if (b) {
+ for (h1 = 0; h1 <= 32; h1++) {
+ struct route4_filter *f;
+
+ for (f = rtnl_dereference(b->ht[h1]);
+ f;
+ f = rtnl_dereference(f->next)) {
+ if (arg->count < arg->skip) {
+ arg->count++;
+ continue;
+ }
+ if (arg->fn(tp, f, arg) < 0) {
+ arg->stop = 1;
+ return;
+ }
+ arg->count++;
+ }
+ }
+ }
+ }
+}
+
+static int route4_dump(struct net *net, struct tcf_proto *tp, void *fh,
+ struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
+{
+ struct route4_filter *f = fh;
+ struct nlattr *nest;
+ u32 id;
+
+ if (f == NULL)
+ return skb->len;
+
+ t->tcm_handle = f->handle;
+
+ nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
+ if (nest == NULL)
+ goto nla_put_failure;
+
+ if (!(f->handle & 0x8000)) {
+ id = f->id & 0xFF;
+ if (nla_put_u32(skb, TCA_ROUTE4_TO, id))
+ goto nla_put_failure;
+ }
+ if (f->handle & 0x80000000) {
+ if ((f->handle >> 16) != 0xFFFF &&
+ nla_put_u32(skb, TCA_ROUTE4_IIF, f->iif))
+ goto nla_put_failure;
+ } else {
+ id = f->id >> 16;
+ if (nla_put_u32(skb, TCA_ROUTE4_FROM, id))
+ goto nla_put_failure;
+ }
+ if (f->res.classid &&
+ nla_put_u32(skb, TCA_ROUTE4_CLASSID, f->res.classid))
+ goto nla_put_failure;
+
+ if (tcf_exts_dump(skb, &f->exts) < 0)
+ goto nla_put_failure;
+
+ nla_nest_end(skb, nest);
+
+ if (tcf_exts_dump_stats(skb, &f->exts) < 0)
+ goto nla_put_failure;
+
+ return skb->len;
+
+nla_put_failure:
+ nla_nest_cancel(skb, nest);
+ return -1;
+}
+
+static void route4_bind_class(void *fh, u32 classid, unsigned long cl, void *q,
+ unsigned long base)
+{
+ struct route4_filter *f = fh;
+
+ if (f && f->res.classid == classid) {
+ if (cl)
+ __tcf_bind_filter(q, &f->res, base);
+ else
+ __tcf_unbind_filter(q, &f->res);
+ }
+}
+
+static struct tcf_proto_ops cls_route4_ops __read_mostly = {
+ .kind = "route",
+ .classify = route4_classify,
+ .init = route4_init,
+ .destroy = route4_destroy,
+ .get = route4_get,
+ .change = route4_change,
+ .delete = route4_delete,
+ .walk = route4_walk,
+ .dump = route4_dump,
+ .bind_class = route4_bind_class,
+ .owner = THIS_MODULE,
+};
+
+static int __init init_route4(void)
+{
+ return register_tcf_proto_ops(&cls_route4_ops);
+}
+
+static void __exit exit_route4(void)
+{
+ unregister_tcf_proto_ops(&cls_route4_ops);
+}
+
+module_init(init_route4)
+module_exit(exit_route4)
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 18:10:08 +0000