| /* |
| * net/sched/cls_route.c ROUTE4 classifier. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| * |
| * 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; |
| } |
| |
| 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 (opt == NULL) |
| return handle ? -EINVAL : 0; |
| |
| err = nla_parse_nested(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->res = fold->res; |
| 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 && fold->handle && f->handle != fold->handle) { |
| 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 == f) { |
| *fp = f->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(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) |
| { |
| struct route4_filter *f = fh; |
| |
| if (f && f->res.classid == classid) |
| f->res.class = cl; |
| } |
| |
| 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"); |