/* * 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 *table[256 + 1]; }; struct route4_bucket { /* 16 FROM buckets + 16 IIF buckets + 1 wildcard bucket */ struct route4_filter *ht[16 + 16 + 1]; }; struct route4_filter { struct route4_filter *next; u32 id; int iif; struct tcf_result res; struct tcf_exts exts; u32 handle; struct route4_bucket *bkt; }; #define ROUTE4_FAILURE ((struct route4_filter *)(-1L)) static inline int route4_fastmap_hash(u32 id, int iif) { return id & 0xF; } static void route4_reset_fastmap(struct Qdisc *q, struct route4_head *head, u32 id) { spinlock_t *root_lock = qdisc_root_sleeping_lock(q); spin_lock_bh(root_lock); memset(head->fastmap, 0, sizeof(head->fastmap)); spin_unlock_bh(root_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); head->fastmap[h].id = id; head->fastmap[h].iif = iif; head->fastmap[h].filter = f; } 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_is_available(&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 = 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; if (head == NULL) goto old_method; iif = inet_iif(skb); h = route4_fastmap_hash(id, iif); if (id == head->fastmap[h].id && iif == head->fastmap[h].iif && (f = head->fastmap[h].filter) != NULL) { if (f == ROUTE4_FAILURE) goto failure; *res = f->res; return 0; } h = route4_hash_to(id); restart: b = head->table[h]; if (b) { for (f = b->ht[route4_hash_from(id)]; f; f = f->next) if (f->id == id) ROUTE4_APPLY_RESULT(); for (f = b->ht[route4_hash_iif(iif)]; f; f = f->next) if (f->iif == iif) ROUTE4_APPLY_RESULT(); for (f = b->ht[route4_hash_wild()]; f; f = 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; old_method: if (id && (TC_H_MAJ(id) == 0 || !(TC_H_MAJ(id^tp->q->handle)))) { res->classid = id; res->class = 0; return 0; } 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 unsigned long route4_get(struct tcf_proto *tp, u32 handle) { struct route4_head *head = tp->root; struct route4_bucket *b; struct route4_filter *f; unsigned int h1, h2; if (!head) return 0; h1 = to_hash(handle); if (h1 > 256) return 0; h2 = from_hash(handle >> 16); if (h2 > 32) return 0; b = head->table[h1]; if (b) { for (f = b->ht[h2]; f; f = f->next) if (f->handle == handle) return (unsigned long)f; } return 0; } static void route4_put(struct tcf_proto *tp, unsigned long f) { } static int route4_init(struct tcf_proto *tp) { return 0; } static void route4_delete_filter(struct tcf_proto *tp, struct route4_filter *f) { tcf_unbind_filter(tp, &f->res); tcf_exts_destroy(tp, &f->exts); kfree(f); } static void route4_destroy(struct tcf_proto *tp) { struct route4_head *head = tp->root; int h1, h2; if (head == NULL) return; for (h1 = 0; h1 <= 256; h1++) { struct route4_bucket *b; b = head->table[h1]; if (b) { for (h2 = 0; h2 <= 32; h2++) { struct route4_filter *f; while ((f = b->ht[h2]) != NULL) { b->ht[h2] = f->next; route4_delete_filter(tp, f); } } kfree(b); } } kfree(head); } static int route4_delete(struct tcf_proto *tp, unsigned long arg) { struct route4_head *head = tp->root; struct route4_filter **fp, *f = (struct route4_filter *)arg; unsigned int h = 0; struct route4_bucket *b; int i; if (!head || !f) return -EINVAL; h = f->handle; b = f->bkt; for (fp = &b->ht[from_hash(h >> 16)]; *fp; fp = &(*fp)->next) { if (*fp == f) { tcf_tree_lock(tp); *fp = f->next; tcf_tree_unlock(tp); route4_reset_fastmap(tp->q, head, f->id); route4_delete_filter(tp, f); /* Strip tree */ for (i = 0; i <= 32; i++) if (b->ht[i]) return 0; /* OK, session has no flows */ tcf_tree_lock(tp); head->table[to_hash(h)] = NULL; tcf_tree_unlock(tp); kfree(b); return 0; } } 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) { int err; u32 id = 0, to = 0, nhandle = 0x8000; struct route4_filter *fp; unsigned int h1; struct route4_bucket *b; struct tcf_exts e; tcf_exts_init(&e, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE); err = tcf_exts_validate(net, tp, tb, est, &e); if (err < 0) return err; err = -EINVAL; if (tb[TCA_ROUTE4_TO]) { if (new && handle & 0x8000) goto errout; to = nla_get_u32(tb[TCA_ROUTE4_TO]); if (to > 0xFF) goto errout; nhandle = to; } if (tb[TCA_ROUTE4_FROM]) { if (tb[TCA_ROUTE4_IIF]) goto errout; id = nla_get_u32(tb[TCA_ROUTE4_FROM]); if (id > 0xFF) goto errout; nhandle |= id << 16; } else if (tb[TCA_ROUTE4_IIF]) { id = nla_get_u32(tb[TCA_ROUTE4_IIF]); if (id > 0x7FFF) goto errout; nhandle |= (id | 0x8000) << 16; } else nhandle |= 0xFFFF << 16; if (handle && new) { nhandle |= handle & 0x7F00; if (nhandle != handle) goto errout; } h1 = to_hash(nhandle); b = head->table[h1]; if (!b) { err = -ENOBUFS; b = kzalloc(sizeof(struct route4_bucket), GFP_KERNEL); if (b == NULL) goto errout; tcf_tree_lock(tp); head->table[h1] = b; tcf_tree_unlock(tp); } else { unsigned int h2 = from_hash(nhandle >> 16); err = -EEXIST; for (fp = b->ht[h2]; fp; fp = fp->next) if (fp->handle == f->handle) goto errout; } tcf_tree_lock(tp); 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; tcf_tree_unlock(tp); if (tb[TCA_ROUTE4_CLASSID]) { f->res.classid = nla_get_u32(tb[TCA_ROUTE4_CLASSID]); tcf_bind_filter(tp, &f->res, base); } tcf_exts_change(tp, &f->exts, &e); return 0; errout: tcf_exts_destroy(tp, &e); return err; } static int route4_change(struct net *net, struct sk_buff *in_skb, struct tcf_proto *tp, unsigned long base, u32 handle, struct nlattr **tca, unsigned long *arg) { struct route4_head *head = tp->root; struct route4_filter *f, *f1, **fp; struct route4_bucket *b; struct nlattr *opt = tca[TCA_OPTIONS]; struct nlattr *tb[TCA_ROUTE4_MAX + 1]; unsigned int h, th; u32 old_handle = 0; int err; if (opt == NULL) return handle ? -EINVAL : 0; err = nla_parse_nested(tb, TCA_ROUTE4_MAX, opt, route4_policy); if (err < 0) return err; f = (struct route4_filter *)*arg; if (f) { if (f->handle != handle && handle) return -EINVAL; if (f->bkt) old_handle = f->handle; err = route4_set_parms(net, tp, base, f, handle, head, tb, tca[TCA_RATE], 0); if (err < 0) return err; goto reinsert; } err = -ENOBUFS; if (head == NULL) { head = kzalloc(sizeof(struct route4_head), GFP_KERNEL); if (head == NULL) goto errout; tcf_tree_lock(tp); tp->root = head; tcf_tree_unlock(tp); } f = kzalloc(sizeof(struct route4_filter), GFP_KERNEL); if (f == NULL) goto errout; tcf_exts_init(&f->exts, TCA_ROUTE4_ACT, TCA_ROUTE4_POLICE); err = route4_set_parms(net, tp, base, f, handle, head, tb, tca[TCA_RATE], 1); if (err < 0) goto errout; reinsert: h = from_hash(f->handle >> 16); for (fp = &f->bkt->ht[h]; (f1 = *fp) != NULL; fp = &f1->next) if (f->handle < f1->handle) break; f->next = f1; tcf_tree_lock(tp); *fp = f; if (old_handle && f->handle != old_handle) { th = to_hash(old_handle); h = from_hash(old_handle >> 16); b = head->table[th]; if (b) { for (fp = &b->ht[h]; *fp; fp = &(*fp)->next) { if (*fp == f) { *fp = f->next; break; } } } } tcf_tree_unlock(tp); route4_reset_fastmap(tp->q, head, f->id); *arg = (unsigned long)f; return 0; errout: kfree(f); return err; } static void route4_walk(struct tcf_proto *tp, struct tcf_walker *arg) { struct route4_head *head = tp->root; unsigned int h, h1; if (head == NULL) arg->stop = 1; if (arg->stop) return; for (h = 0; h <= 256; h++) { struct route4_bucket *b = head->table[h]; if (b) { for (h1 = 0; h1 <= 32; h1++) { struct route4_filter *f; for (f = b->ht[h1]; f; f = f->next) { if (arg->count < arg->skip) { arg->count++; continue; } if (arg->fn(tp, (unsigned long)f, arg) < 0) { arg->stop = 1; return; } arg->count++; } } } } } static int route4_dump(struct net *net, struct tcf_proto *tp, unsigned long fh, struct sk_buff *skb, struct tcmsg *t) { struct route4_filter *f = (struct route4_filter *)fh; unsigned char *b = skb_tail_pointer(skb); 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: nlmsg_trim(skb, b); return -1; } static struct tcf_proto_ops cls_route4_ops __read_mostly = { .kind = "route", .classify = route4_classify, .init = route4_init, .destroy = route4_destroy, .get = route4_get, .put = route4_put, .change = route4_change, .delete = route4_delete, .walk = route4_walk, .dump = route4_dump, .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");