| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * net/sched/cls_fw.c Classifier mapping ipchains' fwmark to traffic class. |
| * |
| * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> |
| * |
| * Changes: |
| * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_walk off by one |
| * Karlis Peisenieks <karlis@mt.lv> : 990415 : fw_delete killed all the filter (and kernel). |
| * Alex <alex@pilotsoft.com> : 2004xxyy: Added Action extension |
| */ |
| |
| #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/netlink.h> |
| #include <net/act_api.h> |
| #include <net/pkt_cls.h> |
| #include <net/sch_generic.h> |
| #include <net/tc_wrapper.h> |
| |
| #define HTSIZE 256 |
| |
| struct fw_head { |
| u32 mask; |
| struct fw_filter __rcu *ht[HTSIZE]; |
| struct rcu_head rcu; |
| }; |
| |
| struct fw_filter { |
| struct fw_filter __rcu *next; |
| u32 id; |
| struct tcf_result res; |
| int ifindex; |
| struct tcf_exts exts; |
| struct tcf_proto *tp; |
| struct rcu_work rwork; |
| }; |
| |
| static u32 fw_hash(u32 handle) |
| { |
| handle ^= (handle >> 16); |
| handle ^= (handle >> 8); |
| return handle % HTSIZE; |
| } |
| |
| TC_INDIRECT_SCOPE int fw_classify(struct sk_buff *skb, |
| const struct tcf_proto *tp, |
| struct tcf_result *res) |
| { |
| struct fw_head *head = rcu_dereference_bh(tp->root); |
| struct fw_filter *f; |
| int r; |
| u32 id = skb->mark; |
| |
| if (head != NULL) { |
| id &= head->mask; |
| |
| for (f = rcu_dereference_bh(head->ht[fw_hash(id)]); f; |
| f = rcu_dereference_bh(f->next)) { |
| if (f->id == id) { |
| *res = f->res; |
| if (!tcf_match_indev(skb, f->ifindex)) |
| continue; |
| r = tcf_exts_exec(skb, &f->exts, res); |
| if (r < 0) |
| continue; |
| |
| return r; |
| } |
| } |
| } else { |
| struct Qdisc *q = tcf_block_q(tp->chain->block); |
| |
| /* Old method: classify the packet using its skb mark. */ |
| if (id && (TC_H_MAJ(id) == 0 || |
| !(TC_H_MAJ(id ^ q->handle)))) { |
| res->classid = id; |
| res->class = 0; |
| return 0; |
| } |
| } |
| |
| return -1; |
| } |
| |
| static void *fw_get(struct tcf_proto *tp, u32 handle) |
| { |
| struct fw_head *head = rtnl_dereference(tp->root); |
| struct fw_filter *f; |
| |
| if (head == NULL) |
| return NULL; |
| |
| f = rtnl_dereference(head->ht[fw_hash(handle)]); |
| for (; f; f = rtnl_dereference(f->next)) { |
| if (f->id == handle) |
| return f; |
| } |
| return NULL; |
| } |
| |
| static int fw_init(struct tcf_proto *tp) |
| { |
| /* We don't allocate fw_head here, because in the old method |
| * we don't need it at all. |
| */ |
| return 0; |
| } |
| |
| static void __fw_delete_filter(struct fw_filter *f) |
| { |
| tcf_exts_destroy(&f->exts); |
| tcf_exts_put_net(&f->exts); |
| kfree(f); |
| } |
| |
| static void fw_delete_filter_work(struct work_struct *work) |
| { |
| struct fw_filter *f = container_of(to_rcu_work(work), |
| struct fw_filter, |
| rwork); |
| rtnl_lock(); |
| __fw_delete_filter(f); |
| rtnl_unlock(); |
| } |
| |
| static void fw_destroy(struct tcf_proto *tp, bool rtnl_held, |
| struct netlink_ext_ack *extack) |
| { |
| struct fw_head *head = rtnl_dereference(tp->root); |
| struct fw_filter *f; |
| int h; |
| |
| if (head == NULL) |
| return; |
| |
| for (h = 0; h < HTSIZE; h++) { |
| while ((f = rtnl_dereference(head->ht[h])) != NULL) { |
| RCU_INIT_POINTER(head->ht[h], |
| rtnl_dereference(f->next)); |
| tcf_unbind_filter(tp, &f->res); |
| if (tcf_exts_get_net(&f->exts)) |
| tcf_queue_work(&f->rwork, fw_delete_filter_work); |
| else |
| __fw_delete_filter(f); |
| } |
| } |
| kfree_rcu(head, rcu); |
| } |
| |
| static int fw_delete(struct tcf_proto *tp, void *arg, bool *last, |
| bool rtnl_held, struct netlink_ext_ack *extack) |
| { |
| struct fw_head *head = rtnl_dereference(tp->root); |
| struct fw_filter *f = arg; |
| struct fw_filter __rcu **fp; |
| struct fw_filter *pfp; |
| int ret = -EINVAL; |
| int h; |
| |
| if (head == NULL || f == NULL) |
| goto out; |
| |
| fp = &head->ht[fw_hash(f->id)]; |
| |
| for (pfp = rtnl_dereference(*fp); pfp; |
| fp = &pfp->next, pfp = rtnl_dereference(*fp)) { |
| if (pfp == f) { |
| RCU_INIT_POINTER(*fp, rtnl_dereference(f->next)); |
| tcf_unbind_filter(tp, &f->res); |
| tcf_exts_get_net(&f->exts); |
| tcf_queue_work(&f->rwork, fw_delete_filter_work); |
| ret = 0; |
| break; |
| } |
| } |
| |
| *last = true; |
| for (h = 0; h < HTSIZE; h++) { |
| if (rcu_access_pointer(head->ht[h])) { |
| *last = false; |
| break; |
| } |
| } |
| |
| out: |
| return ret; |
| } |
| |
| static const struct nla_policy fw_policy[TCA_FW_MAX + 1] = { |
| [TCA_FW_CLASSID] = { .type = NLA_U32 }, |
| [TCA_FW_INDEV] = { .type = NLA_STRING, .len = IFNAMSIZ }, |
| [TCA_FW_MASK] = { .type = NLA_U32 }, |
| }; |
| |
| static int fw_set_parms(struct net *net, struct tcf_proto *tp, |
| struct fw_filter *f, struct nlattr **tb, |
| struct nlattr **tca, unsigned long base, u32 flags, |
| struct netlink_ext_ack *extack) |
| { |
| struct fw_head *head = rtnl_dereference(tp->root); |
| u32 mask; |
| int err; |
| |
| err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &f->exts, flags, |
| extack); |
| if (err < 0) |
| return err; |
| |
| if (tb[TCA_FW_INDEV]) { |
| int ret; |
| ret = tcf_change_indev(net, tb[TCA_FW_INDEV], extack); |
| if (ret < 0) |
| return ret; |
| f->ifindex = ret; |
| } |
| |
| err = -EINVAL; |
| if (tb[TCA_FW_MASK]) { |
| mask = nla_get_u32(tb[TCA_FW_MASK]); |
| if (mask != head->mask) |
| return err; |
| } else if (head->mask != 0xFFFFFFFF) |
| return err; |
| |
| if (tb[TCA_FW_CLASSID]) { |
| f->res.classid = nla_get_u32(tb[TCA_FW_CLASSID]); |
| tcf_bind_filter(tp, &f->res, base); |
| } |
| |
| return 0; |
| } |
| |
| static int fw_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 fw_head *head = rtnl_dereference(tp->root); |
| struct fw_filter *f = *arg; |
| struct nlattr *opt = tca[TCA_OPTIONS]; |
| struct nlattr *tb[TCA_FW_MAX + 1]; |
| int err; |
| |
| if (!opt) |
| return handle ? -EINVAL : 0; /* Succeed if it is old method. */ |
| |
| err = nla_parse_nested_deprecated(tb, TCA_FW_MAX, opt, fw_policy, |
| NULL); |
| if (err < 0) |
| return err; |
| |
| if (f) { |
| struct fw_filter *pfp, *fnew; |
| struct fw_filter __rcu **fp; |
| |
| if (f->id != handle && handle) |
| return -EINVAL; |
| |
| fnew = kzalloc(sizeof(struct fw_filter), GFP_KERNEL); |
| if (!fnew) |
| return -ENOBUFS; |
| |
| fnew->id = f->id; |
| fnew->ifindex = f->ifindex; |
| fnew->tp = f->tp; |
| |
| err = tcf_exts_init(&fnew->exts, net, TCA_FW_ACT, |
| TCA_FW_POLICE); |
| if (err < 0) { |
| kfree(fnew); |
| return err; |
| } |
| |
| err = fw_set_parms(net, tp, fnew, tb, tca, base, flags, extack); |
| if (err < 0) { |
| tcf_exts_destroy(&fnew->exts); |
| kfree(fnew); |
| return err; |
| } |
| |
| fp = &head->ht[fw_hash(fnew->id)]; |
| for (pfp = rtnl_dereference(*fp); pfp; |
| fp = &pfp->next, pfp = rtnl_dereference(*fp)) |
| if (pfp == f) |
| break; |
| |
| RCU_INIT_POINTER(fnew->next, rtnl_dereference(pfp->next)); |
| rcu_assign_pointer(*fp, fnew); |
| tcf_unbind_filter(tp, &f->res); |
| tcf_exts_get_net(&f->exts); |
| tcf_queue_work(&f->rwork, fw_delete_filter_work); |
| |
| *arg = fnew; |
| return err; |
| } |
| |
| if (!handle) |
| return -EINVAL; |
| |
| if (!head) { |
| u32 mask = 0xFFFFFFFF; |
| if (tb[TCA_FW_MASK]) |
| mask = nla_get_u32(tb[TCA_FW_MASK]); |
| |
| head = kzalloc(sizeof(*head), GFP_KERNEL); |
| if (!head) |
| return -ENOBUFS; |
| head->mask = mask; |
| |
| rcu_assign_pointer(tp->root, head); |
| } |
| |
| f = kzalloc(sizeof(struct fw_filter), GFP_KERNEL); |
| if (f == NULL) |
| return -ENOBUFS; |
| |
| err = tcf_exts_init(&f->exts, net, TCA_FW_ACT, TCA_FW_POLICE); |
| if (err < 0) |
| goto errout; |
| f->id = handle; |
| f->tp = tp; |
| |
| err = fw_set_parms(net, tp, f, tb, tca, base, flags, extack); |
| if (err < 0) |
| goto errout; |
| |
| RCU_INIT_POINTER(f->next, head->ht[fw_hash(handle)]); |
| rcu_assign_pointer(head->ht[fw_hash(handle)], f); |
| |
| *arg = f; |
| return 0; |
| |
| errout: |
| tcf_exts_destroy(&f->exts); |
| kfree(f); |
| return err; |
| } |
| |
| static void fw_walk(struct tcf_proto *tp, struct tcf_walker *arg, |
| bool rtnl_held) |
| { |
| struct fw_head *head = rtnl_dereference(tp->root); |
| int h; |
| |
| if (head == NULL) |
| arg->stop = 1; |
| |
| if (arg->stop) |
| return; |
| |
| for (h = 0; h < HTSIZE; h++) { |
| struct fw_filter *f; |
| |
| for (f = rtnl_dereference(head->ht[h]); f; |
| f = rtnl_dereference(f->next)) { |
| if (!tc_cls_stats_dump(tp, arg, f)) |
| return; |
| } |
| } |
| } |
| |
| static int fw_dump(struct net *net, struct tcf_proto *tp, void *fh, |
| struct sk_buff *skb, struct tcmsg *t, bool rtnl_held) |
| { |
| struct fw_head *head = rtnl_dereference(tp->root); |
| struct fw_filter *f = fh; |
| struct nlattr *nest; |
| |
| if (f == NULL) |
| return skb->len; |
| |
| t->tcm_handle = f->id; |
| |
| if (!f->res.classid && !tcf_exts_has_actions(&f->exts)) |
| return skb->len; |
| |
| nest = nla_nest_start_noflag(skb, TCA_OPTIONS); |
| if (nest == NULL) |
| goto nla_put_failure; |
| |
| if (f->res.classid && |
| nla_put_u32(skb, TCA_FW_CLASSID, f->res.classid)) |
| goto nla_put_failure; |
| if (f->ifindex) { |
| struct net_device *dev; |
| dev = __dev_get_by_index(net, f->ifindex); |
| if (dev && nla_put_string(skb, TCA_FW_INDEV, dev->name)) |
| goto nla_put_failure; |
| } |
| if (head->mask != 0xFFFFFFFF && |
| nla_put_u32(skb, TCA_FW_MASK, head->mask)) |
| 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 fw_bind_class(void *fh, u32 classid, unsigned long cl, void *q, |
| unsigned long base) |
| { |
| struct fw_filter *f = fh; |
| |
| tc_cls_bind_class(classid, cl, q, &f->res, base); |
| } |
| |
| static struct tcf_proto_ops cls_fw_ops __read_mostly = { |
| .kind = "fw", |
| .classify = fw_classify, |
| .init = fw_init, |
| .destroy = fw_destroy, |
| .get = fw_get, |
| .change = fw_change, |
| .delete = fw_delete, |
| .walk = fw_walk, |
| .dump = fw_dump, |
| .bind_class = fw_bind_class, |
| .owner = THIS_MODULE, |
| }; |
| |
| static int __init init_fw(void) |
| { |
| return register_tcf_proto_ops(&cls_fw_ops); |
| } |
| |
| static void __exit exit_fw(void) |
| { |
| unregister_tcf_proto_ops(&cls_fw_ops); |
| } |
| |
| module_init(init_fw) |
| module_exit(exit_fw) |
| MODULE_DESCRIPTION("SKB mark based TC classifier"); |
| MODULE_LICENSE("GPL"); |