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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/sched/cls_flow.c
Initial import
Diffstat (limited to 'net/sched/cls_flow.c')
-rw-r--r--net/sched/cls_flow.c694
1 files changed, 694 insertions, 0 deletions
diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
new file mode 100644
index 000000000..a620c4e28
--- /dev/null
+++ b/net/sched/cls_flow.c
@@ -0,0 +1,694 @@
+/*
+ * net/sched/cls_flow.c Generic flow classifier
+ *
+ * Copyright (c) 2007, 2008 Patrick McHardy <kaber@trash.net>
+ *
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/jhash.h>
+#include <linux/random.h>
+#include <linux/pkt_cls.h>
+#include <linux/skbuff.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/if_vlan.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include <net/pkt_cls.h>
+#include <net/ip.h>
+#include <net/route.h>
+#include <net/flow_keys.h>
+
+#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+#include <net/netfilter/nf_conntrack.h>
+#endif
+
+struct flow_head {
+ struct list_head filters;
+ struct rcu_head rcu;
+};
+
+struct flow_filter {
+ struct list_head list;
+ struct tcf_exts exts;
+ struct tcf_ematch_tree ematches;
+ struct tcf_proto *tp;
+ struct timer_list perturb_timer;
+ u32 perturb_period;
+ u32 handle;
+
+ u32 nkeys;
+ u32 keymask;
+ u32 mode;
+ u32 mask;
+ u32 xor;
+ u32 rshift;
+ u32 addend;
+ u32 divisor;
+ u32 baseclass;
+ u32 hashrnd;
+ struct rcu_head rcu;
+};
+
+static inline u32 addr_fold(void *addr)
+{
+ unsigned long a = (unsigned long)addr;
+
+ return (a & 0xFFFFFFFF) ^ (BITS_PER_LONG > 32 ? a >> 32 : 0);
+}
+
+static u32 flow_get_src(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ if (flow->src)
+ return ntohl(flow->src);
+ return addr_fold(skb->sk);
+}
+
+static u32 flow_get_dst(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ if (flow->dst)
+ return ntohl(flow->dst);
+ return addr_fold(skb_dst(skb)) ^ (__force u16) tc_skb_protocol(skb);
+}
+
+static u32 flow_get_proto(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ return flow->ip_proto;
+}
+
+static u32 flow_get_proto_src(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ if (flow->ports)
+ return ntohs(flow->port16[0]);
+
+ return addr_fold(skb->sk);
+}
+
+static u32 flow_get_proto_dst(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ if (flow->ports)
+ return ntohs(flow->port16[1]);
+
+ return addr_fold(skb_dst(skb)) ^ (__force u16) tc_skb_protocol(skb);
+}
+
+static u32 flow_get_iif(const struct sk_buff *skb)
+{
+ return skb->skb_iif;
+}
+
+static u32 flow_get_priority(const struct sk_buff *skb)
+{
+ return skb->priority;
+}
+
+static u32 flow_get_mark(const struct sk_buff *skb)
+{
+ return skb->mark;
+}
+
+static u32 flow_get_nfct(const struct sk_buff *skb)
+{
+#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+ return addr_fold(skb->nfct);
+#else
+ return 0;
+#endif
+}
+
+#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+#define CTTUPLE(skb, member) \
+({ \
+ enum ip_conntrack_info ctinfo; \
+ const struct nf_conn *ct = nf_ct_get(skb, &ctinfo); \
+ if (ct == NULL) \
+ goto fallback; \
+ ct->tuplehash[CTINFO2DIR(ctinfo)].tuple.member; \
+})
+#else
+#define CTTUPLE(skb, member) \
+({ \
+ goto fallback; \
+ 0; \
+})
+#endif
+
+static u32 flow_get_nfct_src(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ switch (tc_skb_protocol(skb)) {
+ case htons(ETH_P_IP):
+ return ntohl(CTTUPLE(skb, src.u3.ip));
+ case htons(ETH_P_IPV6):
+ return ntohl(CTTUPLE(skb, src.u3.ip6[3]));
+ }
+fallback:
+ return flow_get_src(skb, flow);
+}
+
+static u32 flow_get_nfct_dst(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ switch (tc_skb_protocol(skb)) {
+ case htons(ETH_P_IP):
+ return ntohl(CTTUPLE(skb, dst.u3.ip));
+ case htons(ETH_P_IPV6):
+ return ntohl(CTTUPLE(skb, dst.u3.ip6[3]));
+ }
+fallback:
+ return flow_get_dst(skb, flow);
+}
+
+static u32 flow_get_nfct_proto_src(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ return ntohs(CTTUPLE(skb, src.u.all));
+fallback:
+ return flow_get_proto_src(skb, flow);
+}
+
+static u32 flow_get_nfct_proto_dst(const struct sk_buff *skb, const struct flow_keys *flow)
+{
+ return ntohs(CTTUPLE(skb, dst.u.all));
+fallback:
+ return flow_get_proto_dst(skb, flow);
+}
+
+static u32 flow_get_rtclassid(const struct sk_buff *skb)
+{
+#ifdef CONFIG_IP_ROUTE_CLASSID
+ if (skb_dst(skb))
+ return skb_dst(skb)->tclassid;
+#endif
+ return 0;
+}
+
+static u32 flow_get_skuid(const struct sk_buff *skb)
+{
+ if (skb->sk && skb->sk->sk_socket && skb->sk->sk_socket->file) {
+ kuid_t skuid = skb->sk->sk_socket->file->f_cred->fsuid;
+ return from_kuid(&init_user_ns, skuid);
+ }
+ return 0;
+}
+
+static u32 flow_get_skgid(const struct sk_buff *skb)
+{
+ if (skb->sk && skb->sk->sk_socket && skb->sk->sk_socket->file) {
+ kgid_t skgid = skb->sk->sk_socket->file->f_cred->fsgid;
+ return from_kgid(&init_user_ns, skgid);
+ }
+ return 0;
+}
+
+static u32 flow_get_vlan_tag(const struct sk_buff *skb)
+{
+ u16 uninitialized_var(tag);
+
+ if (vlan_get_tag(skb, &tag) < 0)
+ return 0;
+ return tag & VLAN_VID_MASK;
+}
+
+static u32 flow_get_rxhash(struct sk_buff *skb)
+{
+ return skb_get_hash(skb);
+}
+
+static u32 flow_key_get(struct sk_buff *skb, int key, struct flow_keys *flow)
+{
+ switch (key) {
+ case FLOW_KEY_SRC:
+ return flow_get_src(skb, flow);
+ case FLOW_KEY_DST:
+ return flow_get_dst(skb, flow);
+ case FLOW_KEY_PROTO:
+ return flow_get_proto(skb, flow);
+ case FLOW_KEY_PROTO_SRC:
+ return flow_get_proto_src(skb, flow);
+ case FLOW_KEY_PROTO_DST:
+ return flow_get_proto_dst(skb, flow);
+ case FLOW_KEY_IIF:
+ return flow_get_iif(skb);
+ case FLOW_KEY_PRIORITY:
+ return flow_get_priority(skb);
+ case FLOW_KEY_MARK:
+ return flow_get_mark(skb);
+ case FLOW_KEY_NFCT:
+ return flow_get_nfct(skb);
+ case FLOW_KEY_NFCT_SRC:
+ return flow_get_nfct_src(skb, flow);
+ case FLOW_KEY_NFCT_DST:
+ return flow_get_nfct_dst(skb, flow);
+ case FLOW_KEY_NFCT_PROTO_SRC:
+ return flow_get_nfct_proto_src(skb, flow);
+ case FLOW_KEY_NFCT_PROTO_DST:
+ return flow_get_nfct_proto_dst(skb, flow);
+ case FLOW_KEY_RTCLASSID:
+ return flow_get_rtclassid(skb);
+ case FLOW_KEY_SKUID:
+ return flow_get_skuid(skb);
+ case FLOW_KEY_SKGID:
+ return flow_get_skgid(skb);
+ case FLOW_KEY_VLAN_TAG:
+ return flow_get_vlan_tag(skb);
+ case FLOW_KEY_RXHASH:
+ return flow_get_rxhash(skb);
+ default:
+ WARN_ON(1);
+ return 0;
+ }
+}
+
+#define FLOW_KEYS_NEEDED ((1 << FLOW_KEY_SRC) | \
+ (1 << FLOW_KEY_DST) | \
+ (1 << FLOW_KEY_PROTO) | \
+ (1 << FLOW_KEY_PROTO_SRC) | \
+ (1 << FLOW_KEY_PROTO_DST) | \
+ (1 << FLOW_KEY_NFCT_SRC) | \
+ (1 << FLOW_KEY_NFCT_DST) | \
+ (1 << FLOW_KEY_NFCT_PROTO_SRC) | \
+ (1 << FLOW_KEY_NFCT_PROTO_DST))
+
+static int flow_classify(struct sk_buff *skb, const struct tcf_proto *tp,
+ struct tcf_result *res)
+{
+ struct flow_head *head = rcu_dereference_bh(tp->root);
+ struct flow_filter *f;
+ u32 keymask;
+ u32 classid;
+ unsigned int n, key;
+ int r;
+
+ list_for_each_entry_rcu(f, &head->filters, list) {
+ u32 keys[FLOW_KEY_MAX + 1];
+ struct flow_keys flow_keys;
+
+ if (!tcf_em_tree_match(skb, &f->ematches, NULL))
+ continue;
+
+ keymask = f->keymask;
+ if (keymask & FLOW_KEYS_NEEDED)
+ skb_flow_dissect(skb, &flow_keys);
+
+ for (n = 0; n < f->nkeys; n++) {
+ key = ffs(keymask) - 1;
+ keymask &= ~(1 << key);
+ keys[n] = flow_key_get(skb, key, &flow_keys);
+ }
+
+ if (f->mode == FLOW_MODE_HASH)
+ classid = jhash2(keys, f->nkeys, f->hashrnd);
+ else {
+ classid = keys[0];
+ classid = (classid & f->mask) ^ f->xor;
+ classid = (classid >> f->rshift) + f->addend;
+ }
+
+ if (f->divisor)
+ classid %= f->divisor;
+
+ res->class = 0;
+ res->classid = TC_H_MAKE(f->baseclass, f->baseclass + classid);
+
+ r = tcf_exts_exec(skb, &f->exts, res);
+ if (r < 0)
+ continue;
+ return r;
+ }
+ return -1;
+}
+
+static void flow_perturbation(unsigned long arg)
+{
+ struct flow_filter *f = (struct flow_filter *)arg;
+
+ get_random_bytes(&f->hashrnd, 4);
+ if (f->perturb_period)
+ mod_timer(&f->perturb_timer, jiffies + f->perturb_period);
+}
+
+static const struct nla_policy flow_policy[TCA_FLOW_MAX + 1] = {
+ [TCA_FLOW_KEYS] = { .type = NLA_U32 },
+ [TCA_FLOW_MODE] = { .type = NLA_U32 },
+ [TCA_FLOW_BASECLASS] = { .type = NLA_U32 },
+ [TCA_FLOW_RSHIFT] = { .type = NLA_U32 },
+ [TCA_FLOW_ADDEND] = { .type = NLA_U32 },
+ [TCA_FLOW_MASK] = { .type = NLA_U32 },
+ [TCA_FLOW_XOR] = { .type = NLA_U32 },
+ [TCA_FLOW_DIVISOR] = { .type = NLA_U32 },
+ [TCA_FLOW_ACT] = { .type = NLA_NESTED },
+ [TCA_FLOW_POLICE] = { .type = NLA_NESTED },
+ [TCA_FLOW_EMATCHES] = { .type = NLA_NESTED },
+ [TCA_FLOW_PERTURB] = { .type = NLA_U32 },
+};
+
+static void flow_destroy_filter(struct rcu_head *head)
+{
+ struct flow_filter *f = container_of(head, struct flow_filter, rcu);
+
+ del_timer_sync(&f->perturb_timer);
+ tcf_exts_destroy(&f->exts);
+ tcf_em_tree_destroy(&f->ematches);
+ kfree(f);
+}
+
+static int flow_change(struct net *net, struct sk_buff *in_skb,
+ struct tcf_proto *tp, unsigned long base,
+ u32 handle, struct nlattr **tca,
+ unsigned long *arg, bool ovr)
+{
+ struct flow_head *head = rtnl_dereference(tp->root);
+ struct flow_filter *fold, *fnew;
+ struct nlattr *opt = tca[TCA_OPTIONS];
+ struct nlattr *tb[TCA_FLOW_MAX + 1];
+ struct tcf_exts e;
+ struct tcf_ematch_tree t;
+ unsigned int nkeys = 0;
+ unsigned int perturb_period = 0;
+ u32 baseclass = 0;
+ u32 keymask = 0;
+ u32 mode;
+ int err;
+
+ if (opt == NULL)
+ return -EINVAL;
+
+ err = nla_parse_nested(tb, TCA_FLOW_MAX, opt, flow_policy);
+ if (err < 0)
+ return err;
+
+ if (tb[TCA_FLOW_BASECLASS]) {
+ baseclass = nla_get_u32(tb[TCA_FLOW_BASECLASS]);
+ if (TC_H_MIN(baseclass) == 0)
+ return -EINVAL;
+ }
+
+ if (tb[TCA_FLOW_KEYS]) {
+ keymask = nla_get_u32(tb[TCA_FLOW_KEYS]);
+
+ nkeys = hweight32(keymask);
+ if (nkeys == 0)
+ return -EINVAL;
+
+ if (fls(keymask) - 1 > FLOW_KEY_MAX)
+ return -EOPNOTSUPP;
+
+ if ((keymask & (FLOW_KEY_SKUID|FLOW_KEY_SKGID)) &&
+ sk_user_ns(NETLINK_CB(in_skb).sk) != &init_user_ns)
+ return -EOPNOTSUPP;
+ }
+
+ tcf_exts_init(&e, TCA_FLOW_ACT, TCA_FLOW_POLICE);
+ err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &e, ovr);
+ if (err < 0)
+ return err;
+
+ err = tcf_em_tree_validate(tp, tb[TCA_FLOW_EMATCHES], &t);
+ if (err < 0)
+ goto err1;
+
+ err = -ENOBUFS;
+ fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
+ if (!fnew)
+ goto err2;
+
+ fold = (struct flow_filter *)*arg;
+ if (fold) {
+ err = -EINVAL;
+ if (fold->handle != handle && handle)
+ goto err2;
+
+ /* Copy fold into fnew */
+ fnew->tp = fold->tp;
+ fnew->handle = fold->handle;
+ fnew->nkeys = fold->nkeys;
+ fnew->keymask = fold->keymask;
+ fnew->mode = fold->mode;
+ fnew->mask = fold->mask;
+ fnew->xor = fold->xor;
+ fnew->rshift = fold->rshift;
+ fnew->addend = fold->addend;
+ fnew->divisor = fold->divisor;
+ fnew->baseclass = fold->baseclass;
+ fnew->hashrnd = fold->hashrnd;
+
+ mode = fold->mode;
+ if (tb[TCA_FLOW_MODE])
+ mode = nla_get_u32(tb[TCA_FLOW_MODE]);
+ if (mode != FLOW_MODE_HASH && nkeys > 1)
+ goto err2;
+
+ if (mode == FLOW_MODE_HASH)
+ perturb_period = fold->perturb_period;
+ if (tb[TCA_FLOW_PERTURB]) {
+ if (mode != FLOW_MODE_HASH)
+ goto err2;
+ perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ;
+ }
+ } else {
+ err = -EINVAL;
+ if (!handle)
+ goto err2;
+ if (!tb[TCA_FLOW_KEYS])
+ goto err2;
+
+ mode = FLOW_MODE_MAP;
+ if (tb[TCA_FLOW_MODE])
+ mode = nla_get_u32(tb[TCA_FLOW_MODE]);
+ if (mode != FLOW_MODE_HASH && nkeys > 1)
+ goto err2;
+
+ if (tb[TCA_FLOW_PERTURB]) {
+ if (mode != FLOW_MODE_HASH)
+ goto err2;
+ perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ;
+ }
+
+ if (TC_H_MAJ(baseclass) == 0)
+ baseclass = TC_H_MAKE(tp->q->handle, baseclass);
+ if (TC_H_MIN(baseclass) == 0)
+ baseclass = TC_H_MAKE(baseclass, 1);
+
+ fnew->handle = handle;
+ fnew->mask = ~0U;
+ fnew->tp = tp;
+ get_random_bytes(&fnew->hashrnd, 4);
+ tcf_exts_init(&fnew->exts, TCA_FLOW_ACT, TCA_FLOW_POLICE);
+ }
+
+ fnew->perturb_timer.function = flow_perturbation;
+ fnew->perturb_timer.data = (unsigned long)fnew;
+ init_timer_deferrable(&fnew->perturb_timer);
+
+ tcf_exts_change(tp, &fnew->exts, &e);
+ tcf_em_tree_change(tp, &fnew->ematches, &t);
+
+ netif_keep_dst(qdisc_dev(tp->q));
+
+ if (tb[TCA_FLOW_KEYS]) {
+ fnew->keymask = keymask;
+ fnew->nkeys = nkeys;
+ }
+
+ fnew->mode = mode;
+
+ if (tb[TCA_FLOW_MASK])
+ fnew->mask = nla_get_u32(tb[TCA_FLOW_MASK]);
+ if (tb[TCA_FLOW_XOR])
+ fnew->xor = nla_get_u32(tb[TCA_FLOW_XOR]);
+ if (tb[TCA_FLOW_RSHIFT])
+ fnew->rshift = nla_get_u32(tb[TCA_FLOW_RSHIFT]);
+ if (tb[TCA_FLOW_ADDEND])
+ fnew->addend = nla_get_u32(tb[TCA_FLOW_ADDEND]);
+
+ if (tb[TCA_FLOW_DIVISOR])
+ fnew->divisor = nla_get_u32(tb[TCA_FLOW_DIVISOR]);
+ if (baseclass)
+ fnew->baseclass = baseclass;
+
+ fnew->perturb_period = perturb_period;
+ if (perturb_period)
+ mod_timer(&fnew->perturb_timer, jiffies + perturb_period);
+
+ if (*arg == 0)
+ list_add_tail_rcu(&fnew->list, &head->filters);
+ else
+ list_replace_rcu(&fnew->list, &fold->list);
+
+ *arg = (unsigned long)fnew;
+
+ if (fold)
+ call_rcu(&fold->rcu, flow_destroy_filter);
+ return 0;
+
+err2:
+ tcf_em_tree_destroy(&t);
+ kfree(fnew);
+err1:
+ tcf_exts_destroy(&e);
+ return err;
+}
+
+static int flow_delete(struct tcf_proto *tp, unsigned long arg)
+{
+ struct flow_filter *f = (struct flow_filter *)arg;
+
+ list_del_rcu(&f->list);
+ call_rcu(&f->rcu, flow_destroy_filter);
+ return 0;
+}
+
+static int flow_init(struct tcf_proto *tp)
+{
+ struct flow_head *head;
+
+ head = kzalloc(sizeof(*head), GFP_KERNEL);
+ if (head == NULL)
+ return -ENOBUFS;
+ INIT_LIST_HEAD(&head->filters);
+ rcu_assign_pointer(tp->root, head);
+ return 0;
+}
+
+static bool flow_destroy(struct tcf_proto *tp, bool force)
+{
+ struct flow_head *head = rtnl_dereference(tp->root);
+ struct flow_filter *f, *next;
+
+ if (!force && !list_empty(&head->filters))
+ return false;
+
+ list_for_each_entry_safe(f, next, &head->filters, list) {
+ list_del_rcu(&f->list);
+ call_rcu(&f->rcu, flow_destroy_filter);
+ }
+ RCU_INIT_POINTER(tp->root, NULL);
+ kfree_rcu(head, rcu);
+ return true;
+}
+
+static unsigned long flow_get(struct tcf_proto *tp, u32 handle)
+{
+ struct flow_head *head = rtnl_dereference(tp->root);
+ struct flow_filter *f;
+
+ list_for_each_entry(f, &head->filters, list)
+ if (f->handle == handle)
+ return (unsigned long)f;
+ return 0;
+}
+
+static int flow_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
+ struct sk_buff *skb, struct tcmsg *t)
+{
+ struct flow_filter *f = (struct flow_filter *)fh;
+ struct nlattr *nest;
+
+ 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 (nla_put_u32(skb, TCA_FLOW_KEYS, f->keymask) ||
+ nla_put_u32(skb, TCA_FLOW_MODE, f->mode))
+ goto nla_put_failure;
+
+ if (f->mask != ~0 || f->xor != 0) {
+ if (nla_put_u32(skb, TCA_FLOW_MASK, f->mask) ||
+ nla_put_u32(skb, TCA_FLOW_XOR, f->xor))
+ goto nla_put_failure;
+ }
+ if (f->rshift &&
+ nla_put_u32(skb, TCA_FLOW_RSHIFT, f->rshift))
+ goto nla_put_failure;
+ if (f->addend &&
+ nla_put_u32(skb, TCA_FLOW_ADDEND, f->addend))
+ goto nla_put_failure;
+
+ if (f->divisor &&
+ nla_put_u32(skb, TCA_FLOW_DIVISOR, f->divisor))
+ goto nla_put_failure;
+ if (f->baseclass &&
+ nla_put_u32(skb, TCA_FLOW_BASECLASS, f->baseclass))
+ goto nla_put_failure;
+
+ if (f->perturb_period &&
+ nla_put_u32(skb, TCA_FLOW_PERTURB, f->perturb_period / HZ))
+ goto nla_put_failure;
+
+ if (tcf_exts_dump(skb, &f->exts) < 0)
+ goto nla_put_failure;
+#ifdef CONFIG_NET_EMATCH
+ if (f->ematches.hdr.nmatches &&
+ tcf_em_tree_dump(skb, &f->ematches, TCA_FLOW_EMATCHES) < 0)
+ goto nla_put_failure;
+#endif
+ 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 flow_walk(struct tcf_proto *tp, struct tcf_walker *arg)
+{
+ struct flow_head *head = rtnl_dereference(tp->root);
+ struct flow_filter *f;
+
+ list_for_each_entry(f, &head->filters, list) {
+ if (arg->count < arg->skip)
+ goto skip;
+ if (arg->fn(tp, (unsigned long)f, arg) < 0) {
+ arg->stop = 1;
+ break;
+ }
+skip:
+ arg->count++;
+ }
+}
+
+static struct tcf_proto_ops cls_flow_ops __read_mostly = {
+ .kind = "flow",
+ .classify = flow_classify,
+ .init = flow_init,
+ .destroy = flow_destroy,
+ .change = flow_change,
+ .delete = flow_delete,
+ .get = flow_get,
+ .dump = flow_dump,
+ .walk = flow_walk,
+ .owner = THIS_MODULE,
+};
+
+static int __init cls_flow_init(void)
+{
+ return register_tcf_proto_ops(&cls_flow_ops);
+}
+
+static void __exit cls_flow_exit(void)
+{
+ unregister_tcf_proto_ops(&cls_flow_ops);
+}
+
+module_init(cls_flow_init);
+module_exit(cls_flow_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_DESCRIPTION("TC flow classifier");