| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * net/sched/cls_api.c Packet classifier API. |
| * |
| * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> |
| * |
| * Changes: |
| * |
| * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/string.h> |
| #include <linux/errno.h> |
| #include <linux/err.h> |
| #include <linux/skbuff.h> |
| #include <linux/init.h> |
| #include <linux/kmod.h> |
| #include <linux/slab.h> |
| #include <linux/idr.h> |
| #include <linux/jhash.h> |
| #include <linux/rculist.h> |
| #include <net/net_namespace.h> |
| #include <net/sock.h> |
| #include <net/netlink.h> |
| #include <net/pkt_sched.h> |
| #include <net/pkt_cls.h> |
| #include <net/tc_act/tc_pedit.h> |
| #include <net/tc_act/tc_mirred.h> |
| #include <net/tc_act/tc_vlan.h> |
| #include <net/tc_act/tc_tunnel_key.h> |
| #include <net/tc_act/tc_csum.h> |
| #include <net/tc_act/tc_gact.h> |
| #include <net/tc_act/tc_police.h> |
| #include <net/tc_act/tc_sample.h> |
| #include <net/tc_act/tc_skbedit.h> |
| #include <net/tc_act/tc_ct.h> |
| #include <net/tc_act/tc_mpls.h> |
| #include <net/tc_act/tc_gate.h> |
| #include <net/flow_offload.h> |
| |
| extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1]; |
| |
| /* The list of all installed classifier types */ |
| static LIST_HEAD(tcf_proto_base); |
| |
| /* Protects list of registered TC modules. It is pure SMP lock. */ |
| static DEFINE_RWLOCK(cls_mod_lock); |
| |
| static u32 destroy_obj_hashfn(const struct tcf_proto *tp) |
| { |
| return jhash_3words(tp->chain->index, tp->prio, |
| (__force __u32)tp->protocol, 0); |
| } |
| |
| static void tcf_proto_signal_destroying(struct tcf_chain *chain, |
| struct tcf_proto *tp) |
| { |
| struct tcf_block *block = chain->block; |
| |
| mutex_lock(&block->proto_destroy_lock); |
| hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node, |
| destroy_obj_hashfn(tp)); |
| mutex_unlock(&block->proto_destroy_lock); |
| } |
| |
| static bool tcf_proto_cmp(const struct tcf_proto *tp1, |
| const struct tcf_proto *tp2) |
| { |
| return tp1->chain->index == tp2->chain->index && |
| tp1->prio == tp2->prio && |
| tp1->protocol == tp2->protocol; |
| } |
| |
| static bool tcf_proto_exists_destroying(struct tcf_chain *chain, |
| struct tcf_proto *tp) |
| { |
| u32 hash = destroy_obj_hashfn(tp); |
| struct tcf_proto *iter; |
| bool found = false; |
| |
| rcu_read_lock(); |
| hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter, |
| destroy_ht_node, hash) { |
| if (tcf_proto_cmp(tp, iter)) { |
| found = true; |
| break; |
| } |
| } |
| rcu_read_unlock(); |
| |
| return found; |
| } |
| |
| static void |
| tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp) |
| { |
| struct tcf_block *block = chain->block; |
| |
| mutex_lock(&block->proto_destroy_lock); |
| if (hash_hashed(&tp->destroy_ht_node)) |
| hash_del_rcu(&tp->destroy_ht_node); |
| mutex_unlock(&block->proto_destroy_lock); |
| } |
| |
| /* Find classifier type by string name */ |
| |
| static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind) |
| { |
| const struct tcf_proto_ops *t, *res = NULL; |
| |
| if (kind) { |
| read_lock(&cls_mod_lock); |
| list_for_each_entry(t, &tcf_proto_base, head) { |
| if (strcmp(kind, t->kind) == 0) { |
| if (try_module_get(t->owner)) |
| res = t; |
| break; |
| } |
| } |
| read_unlock(&cls_mod_lock); |
| } |
| return res; |
| } |
| |
| static const struct tcf_proto_ops * |
| tcf_proto_lookup_ops(const char *kind, bool rtnl_held, |
| struct netlink_ext_ack *extack) |
| { |
| const struct tcf_proto_ops *ops; |
| |
| ops = __tcf_proto_lookup_ops(kind); |
| if (ops) |
| return ops; |
| #ifdef CONFIG_MODULES |
| if (rtnl_held) |
| rtnl_unlock(); |
| request_module("cls_%s", kind); |
| if (rtnl_held) |
| rtnl_lock(); |
| ops = __tcf_proto_lookup_ops(kind); |
| /* We dropped the RTNL semaphore in order to perform |
| * the module load. So, even if we succeeded in loading |
| * the module we have to replay the request. We indicate |
| * this using -EAGAIN. |
| */ |
| if (ops) { |
| module_put(ops->owner); |
| return ERR_PTR(-EAGAIN); |
| } |
| #endif |
| NL_SET_ERR_MSG(extack, "TC classifier not found"); |
| return ERR_PTR(-ENOENT); |
| } |
| |
| /* Register(unregister) new classifier type */ |
| |
| int register_tcf_proto_ops(struct tcf_proto_ops *ops) |
| { |
| struct tcf_proto_ops *t; |
| int rc = -EEXIST; |
| |
| write_lock(&cls_mod_lock); |
| list_for_each_entry(t, &tcf_proto_base, head) |
| if (!strcmp(ops->kind, t->kind)) |
| goto out; |
| |
| list_add_tail(&ops->head, &tcf_proto_base); |
| rc = 0; |
| out: |
| write_unlock(&cls_mod_lock); |
| return rc; |
| } |
| EXPORT_SYMBOL(register_tcf_proto_ops); |
| |
| static struct workqueue_struct *tc_filter_wq; |
| |
| int unregister_tcf_proto_ops(struct tcf_proto_ops *ops) |
| { |
| struct tcf_proto_ops *t; |
| int rc = -ENOENT; |
| |
| /* Wait for outstanding call_rcu()s, if any, from a |
| * tcf_proto_ops's destroy() handler. |
| */ |
| rcu_barrier(); |
| flush_workqueue(tc_filter_wq); |
| |
| write_lock(&cls_mod_lock); |
| list_for_each_entry(t, &tcf_proto_base, head) { |
| if (t == ops) { |
| list_del(&t->head); |
| rc = 0; |
| break; |
| } |
| } |
| write_unlock(&cls_mod_lock); |
| return rc; |
| } |
| EXPORT_SYMBOL(unregister_tcf_proto_ops); |
| |
| bool tcf_queue_work(struct rcu_work *rwork, work_func_t func) |
| { |
| INIT_RCU_WORK(rwork, func); |
| return queue_rcu_work(tc_filter_wq, rwork); |
| } |
| EXPORT_SYMBOL(tcf_queue_work); |
| |
| /* Select new prio value from the range, managed by kernel. */ |
| |
| static inline u32 tcf_auto_prio(struct tcf_proto *tp) |
| { |
| u32 first = TC_H_MAKE(0xC0000000U, 0U); |
| |
| if (tp) |
| first = tp->prio - 1; |
| |
| return TC_H_MAJ(first); |
| } |
| |
| static bool tcf_proto_check_kind(struct nlattr *kind, char *name) |
| { |
| if (kind) |
| return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ; |
| memset(name, 0, IFNAMSIZ); |
| return false; |
| } |
| |
| static bool tcf_proto_is_unlocked(const char *kind) |
| { |
| const struct tcf_proto_ops *ops; |
| bool ret; |
| |
| if (strlen(kind) == 0) |
| return false; |
| |
| ops = tcf_proto_lookup_ops(kind, false, NULL); |
| /* On error return false to take rtnl lock. Proto lookup/create |
| * functions will perform lookup again and properly handle errors. |
| */ |
| if (IS_ERR(ops)) |
| return false; |
| |
| ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED); |
| module_put(ops->owner); |
| return ret; |
| } |
| |
| static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol, |
| u32 prio, struct tcf_chain *chain, |
| bool rtnl_held, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_proto *tp; |
| int err; |
| |
| tp = kzalloc(sizeof(*tp), GFP_KERNEL); |
| if (!tp) |
| return ERR_PTR(-ENOBUFS); |
| |
| tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack); |
| if (IS_ERR(tp->ops)) { |
| err = PTR_ERR(tp->ops); |
| goto errout; |
| } |
| tp->classify = tp->ops->classify; |
| tp->protocol = protocol; |
| tp->prio = prio; |
| tp->chain = chain; |
| spin_lock_init(&tp->lock); |
| refcount_set(&tp->refcnt, 1); |
| |
| err = tp->ops->init(tp); |
| if (err) { |
| module_put(tp->ops->owner); |
| goto errout; |
| } |
| return tp; |
| |
| errout: |
| kfree(tp); |
| return ERR_PTR(err); |
| } |
| |
| static void tcf_proto_get(struct tcf_proto *tp) |
| { |
| refcount_inc(&tp->refcnt); |
| } |
| |
| static void tcf_chain_put(struct tcf_chain *chain); |
| |
| static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held, |
| bool sig_destroy, struct netlink_ext_ack *extack) |
| { |
| tp->ops->destroy(tp, rtnl_held, extack); |
| if (sig_destroy) |
| tcf_proto_signal_destroyed(tp->chain, tp); |
| tcf_chain_put(tp->chain); |
| module_put(tp->ops->owner); |
| kfree_rcu(tp, rcu); |
| } |
| |
| static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held, |
| struct netlink_ext_ack *extack) |
| { |
| if (refcount_dec_and_test(&tp->refcnt)) |
| tcf_proto_destroy(tp, rtnl_held, true, extack); |
| } |
| |
| static bool tcf_proto_check_delete(struct tcf_proto *tp) |
| { |
| if (tp->ops->delete_empty) |
| return tp->ops->delete_empty(tp); |
| |
| tp->deleting = true; |
| return tp->deleting; |
| } |
| |
| static void tcf_proto_mark_delete(struct tcf_proto *tp) |
| { |
| spin_lock(&tp->lock); |
| tp->deleting = true; |
| spin_unlock(&tp->lock); |
| } |
| |
| static bool tcf_proto_is_deleting(struct tcf_proto *tp) |
| { |
| bool deleting; |
| |
| spin_lock(&tp->lock); |
| deleting = tp->deleting; |
| spin_unlock(&tp->lock); |
| |
| return deleting; |
| } |
| |
| #define ASSERT_BLOCK_LOCKED(block) \ |
| lockdep_assert_held(&(block)->lock) |
| |
| struct tcf_filter_chain_list_item { |
| struct list_head list; |
| tcf_chain_head_change_t *chain_head_change; |
| void *chain_head_change_priv; |
| }; |
| |
| static struct tcf_chain *tcf_chain_create(struct tcf_block *block, |
| u32 chain_index) |
| { |
| struct tcf_chain *chain; |
| |
| ASSERT_BLOCK_LOCKED(block); |
| |
| chain = kzalloc(sizeof(*chain), GFP_KERNEL); |
| if (!chain) |
| return NULL; |
| list_add_tail_rcu(&chain->list, &block->chain_list); |
| mutex_init(&chain->filter_chain_lock); |
| chain->block = block; |
| chain->index = chain_index; |
| chain->refcnt = 1; |
| if (!chain->index) |
| block->chain0.chain = chain; |
| return chain; |
| } |
| |
| static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item, |
| struct tcf_proto *tp_head) |
| { |
| if (item->chain_head_change) |
| item->chain_head_change(tp_head, item->chain_head_change_priv); |
| } |
| |
| static void tcf_chain0_head_change(struct tcf_chain *chain, |
| struct tcf_proto *tp_head) |
| { |
| struct tcf_filter_chain_list_item *item; |
| struct tcf_block *block = chain->block; |
| |
| if (chain->index) |
| return; |
| |
| mutex_lock(&block->lock); |
| list_for_each_entry(item, &block->chain0.filter_chain_list, list) |
| tcf_chain_head_change_item(item, tp_head); |
| mutex_unlock(&block->lock); |
| } |
| |
| /* Returns true if block can be safely freed. */ |
| |
| static bool tcf_chain_detach(struct tcf_chain *chain) |
| { |
| struct tcf_block *block = chain->block; |
| |
| ASSERT_BLOCK_LOCKED(block); |
| |
| list_del_rcu(&chain->list); |
| if (!chain->index) |
| block->chain0.chain = NULL; |
| |
| if (list_empty(&block->chain_list) && |
| refcount_read(&block->refcnt) == 0) |
| return true; |
| |
| return false; |
| } |
| |
| static void tcf_block_destroy(struct tcf_block *block) |
| { |
| mutex_destroy(&block->lock); |
| mutex_destroy(&block->proto_destroy_lock); |
| kfree_rcu(block, rcu); |
| } |
| |
| static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block) |
| { |
| struct tcf_block *block = chain->block; |
| |
| mutex_destroy(&chain->filter_chain_lock); |
| kfree_rcu(chain, rcu); |
| if (free_block) |
| tcf_block_destroy(block); |
| } |
| |
| static void tcf_chain_hold(struct tcf_chain *chain) |
| { |
| ASSERT_BLOCK_LOCKED(chain->block); |
| |
| ++chain->refcnt; |
| } |
| |
| static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain) |
| { |
| ASSERT_BLOCK_LOCKED(chain->block); |
| |
| /* In case all the references are action references, this |
| * chain should not be shown to the user. |
| */ |
| return chain->refcnt == chain->action_refcnt; |
| } |
| |
| static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block, |
| u32 chain_index) |
| { |
| struct tcf_chain *chain; |
| |
| ASSERT_BLOCK_LOCKED(block); |
| |
| list_for_each_entry(chain, &block->chain_list, list) { |
| if (chain->index == chain_index) |
| return chain; |
| } |
| return NULL; |
| } |
| |
| #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT) |
| static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block, |
| u32 chain_index) |
| { |
| struct tcf_chain *chain; |
| |
| list_for_each_entry_rcu(chain, &block->chain_list, list) { |
| if (chain->index == chain_index) |
| return chain; |
| } |
| return NULL; |
| } |
| #endif |
| |
| static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb, |
| u32 seq, u16 flags, int event, bool unicast); |
| |
| static struct tcf_chain *__tcf_chain_get(struct tcf_block *block, |
| u32 chain_index, bool create, |
| bool by_act) |
| { |
| struct tcf_chain *chain = NULL; |
| bool is_first_reference; |
| |
| mutex_lock(&block->lock); |
| chain = tcf_chain_lookup(block, chain_index); |
| if (chain) { |
| tcf_chain_hold(chain); |
| } else { |
| if (!create) |
| goto errout; |
| chain = tcf_chain_create(block, chain_index); |
| if (!chain) |
| goto errout; |
| } |
| |
| if (by_act) |
| ++chain->action_refcnt; |
| is_first_reference = chain->refcnt - chain->action_refcnt == 1; |
| mutex_unlock(&block->lock); |
| |
| /* Send notification only in case we got the first |
| * non-action reference. Until then, the chain acts only as |
| * a placeholder for actions pointing to it and user ought |
| * not know about them. |
| */ |
| if (is_first_reference && !by_act) |
| tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL, |
| RTM_NEWCHAIN, false); |
| |
| return chain; |
| |
| errout: |
| mutex_unlock(&block->lock); |
| return chain; |
| } |
| |
| static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index, |
| bool create) |
| { |
| return __tcf_chain_get(block, chain_index, create, false); |
| } |
| |
| struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index) |
| { |
| return __tcf_chain_get(block, chain_index, true, true); |
| } |
| EXPORT_SYMBOL(tcf_chain_get_by_act); |
| |
| static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops, |
| void *tmplt_priv); |
| static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops, |
| void *tmplt_priv, u32 chain_index, |
| struct tcf_block *block, struct sk_buff *oskb, |
| u32 seq, u16 flags, bool unicast); |
| |
| static void __tcf_chain_put(struct tcf_chain *chain, bool by_act, |
| bool explicitly_created) |
| { |
| struct tcf_block *block = chain->block; |
| const struct tcf_proto_ops *tmplt_ops; |
| bool free_block = false; |
| unsigned int refcnt; |
| void *tmplt_priv; |
| |
| mutex_lock(&block->lock); |
| if (explicitly_created) { |
| if (!chain->explicitly_created) { |
| mutex_unlock(&block->lock); |
| return; |
| } |
| chain->explicitly_created = false; |
| } |
| |
| if (by_act) |
| chain->action_refcnt--; |
| |
| /* tc_chain_notify_delete can't be called while holding block lock. |
| * However, when block is unlocked chain can be changed concurrently, so |
| * save these to temporary variables. |
| */ |
| refcnt = --chain->refcnt; |
| tmplt_ops = chain->tmplt_ops; |
| tmplt_priv = chain->tmplt_priv; |
| |
| /* The last dropped non-action reference will trigger notification. */ |
| if (refcnt - chain->action_refcnt == 0 && !by_act) { |
| tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index, |
| block, NULL, 0, 0, false); |
| /* Last reference to chain, no need to lock. */ |
| chain->flushing = false; |
| } |
| |
| if (refcnt == 0) |
| free_block = tcf_chain_detach(chain); |
| mutex_unlock(&block->lock); |
| |
| if (refcnt == 0) { |
| tc_chain_tmplt_del(tmplt_ops, tmplt_priv); |
| tcf_chain_destroy(chain, free_block); |
| } |
| } |
| |
| static void tcf_chain_put(struct tcf_chain *chain) |
| { |
| __tcf_chain_put(chain, false, false); |
| } |
| |
| void tcf_chain_put_by_act(struct tcf_chain *chain) |
| { |
| __tcf_chain_put(chain, true, false); |
| } |
| EXPORT_SYMBOL(tcf_chain_put_by_act); |
| |
| static void tcf_chain_put_explicitly_created(struct tcf_chain *chain) |
| { |
| __tcf_chain_put(chain, false, true); |
| } |
| |
| static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held) |
| { |
| struct tcf_proto *tp, *tp_next; |
| |
| mutex_lock(&chain->filter_chain_lock); |
| tp = tcf_chain_dereference(chain->filter_chain, chain); |
| while (tp) { |
| tp_next = rcu_dereference_protected(tp->next, 1); |
| tcf_proto_signal_destroying(chain, tp); |
| tp = tp_next; |
| } |
| tp = tcf_chain_dereference(chain->filter_chain, chain); |
| RCU_INIT_POINTER(chain->filter_chain, NULL); |
| tcf_chain0_head_change(chain, NULL); |
| chain->flushing = true; |
| mutex_unlock(&chain->filter_chain_lock); |
| |
| while (tp) { |
| tp_next = rcu_dereference_protected(tp->next, 1); |
| tcf_proto_put(tp, rtnl_held, NULL); |
| tp = tp_next; |
| } |
| } |
| |
| static int tcf_block_setup(struct tcf_block *block, |
| struct flow_block_offload *bo); |
| |
| static void tcf_block_offload_init(struct flow_block_offload *bo, |
| struct net_device *dev, struct Qdisc *sch, |
| enum flow_block_command command, |
| enum flow_block_binder_type binder_type, |
| struct flow_block *flow_block, |
| bool shared, struct netlink_ext_ack *extack) |
| { |
| bo->net = dev_net(dev); |
| bo->command = command; |
| bo->binder_type = binder_type; |
| bo->block = flow_block; |
| bo->block_shared = shared; |
| bo->extack = extack; |
| bo->sch = sch; |
| INIT_LIST_HEAD(&bo->cb_list); |
| } |
| |
| static void tcf_block_unbind(struct tcf_block *block, |
| struct flow_block_offload *bo); |
| |
| static void tc_block_indr_cleanup(struct flow_block_cb *block_cb) |
| { |
| struct tcf_block *block = block_cb->indr.data; |
| struct net_device *dev = block_cb->indr.dev; |
| struct Qdisc *sch = block_cb->indr.sch; |
| struct netlink_ext_ack extack = {}; |
| struct flow_block_offload bo; |
| |
| tcf_block_offload_init(&bo, dev, sch, FLOW_BLOCK_UNBIND, |
| block_cb->indr.binder_type, |
| &block->flow_block, tcf_block_shared(block), |
| &extack); |
| down_write(&block->cb_lock); |
| list_del(&block_cb->driver_list); |
| list_move(&block_cb->list, &bo.cb_list); |
| up_write(&block->cb_lock); |
| rtnl_lock(); |
| tcf_block_unbind(block, &bo); |
| rtnl_unlock(); |
| } |
| |
| static bool tcf_block_offload_in_use(struct tcf_block *block) |
| { |
| return atomic_read(&block->offloadcnt); |
| } |
| |
| static int tcf_block_offload_cmd(struct tcf_block *block, |
| struct net_device *dev, struct Qdisc *sch, |
| struct tcf_block_ext_info *ei, |
| enum flow_block_command command, |
| struct netlink_ext_ack *extack) |
| { |
| struct flow_block_offload bo = {}; |
| |
| tcf_block_offload_init(&bo, dev, sch, command, ei->binder_type, |
| &block->flow_block, tcf_block_shared(block), |
| extack); |
| |
| if (dev->netdev_ops->ndo_setup_tc) { |
| int err; |
| |
| err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo); |
| if (err < 0) { |
| if (err != -EOPNOTSUPP) |
| NL_SET_ERR_MSG(extack, "Driver ndo_setup_tc failed"); |
| return err; |
| } |
| |
| return tcf_block_setup(block, &bo); |
| } |
| |
| flow_indr_dev_setup_offload(dev, sch, TC_SETUP_BLOCK, block, &bo, |
| tc_block_indr_cleanup); |
| tcf_block_setup(block, &bo); |
| |
| return -EOPNOTSUPP; |
| } |
| |
| static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q, |
| struct tcf_block_ext_info *ei, |
| struct netlink_ext_ack *extack) |
| { |
| struct net_device *dev = q->dev_queue->dev; |
| int err; |
| |
| down_write(&block->cb_lock); |
| |
| /* If tc offload feature is disabled and the block we try to bind |
| * to already has some offloaded filters, forbid to bind. |
| */ |
| if (dev->netdev_ops->ndo_setup_tc && |
| !tc_can_offload(dev) && |
| tcf_block_offload_in_use(block)) { |
| NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled"); |
| err = -EOPNOTSUPP; |
| goto err_unlock; |
| } |
| |
| err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_BIND, extack); |
| if (err == -EOPNOTSUPP) |
| goto no_offload_dev_inc; |
| if (err) |
| goto err_unlock; |
| |
| up_write(&block->cb_lock); |
| return 0; |
| |
| no_offload_dev_inc: |
| if (tcf_block_offload_in_use(block)) |
| goto err_unlock; |
| |
| err = 0; |
| block->nooffloaddevcnt++; |
| err_unlock: |
| up_write(&block->cb_lock); |
| return err; |
| } |
| |
| static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q, |
| struct tcf_block_ext_info *ei) |
| { |
| struct net_device *dev = q->dev_queue->dev; |
| int err; |
| |
| down_write(&block->cb_lock); |
| err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_UNBIND, NULL); |
| if (err == -EOPNOTSUPP) |
| goto no_offload_dev_dec; |
| up_write(&block->cb_lock); |
| return; |
| |
| no_offload_dev_dec: |
| WARN_ON(block->nooffloaddevcnt-- == 0); |
| up_write(&block->cb_lock); |
| } |
| |
| static int |
| tcf_chain0_head_change_cb_add(struct tcf_block *block, |
| struct tcf_block_ext_info *ei, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_filter_chain_list_item *item; |
| struct tcf_chain *chain0; |
| |
| item = kmalloc(sizeof(*item), GFP_KERNEL); |
| if (!item) { |
| NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed"); |
| return -ENOMEM; |
| } |
| item->chain_head_change = ei->chain_head_change; |
| item->chain_head_change_priv = ei->chain_head_change_priv; |
| |
| mutex_lock(&block->lock); |
| chain0 = block->chain0.chain; |
| if (chain0) |
| tcf_chain_hold(chain0); |
| else |
| list_add(&item->list, &block->chain0.filter_chain_list); |
| mutex_unlock(&block->lock); |
| |
| if (chain0) { |
| struct tcf_proto *tp_head; |
| |
| mutex_lock(&chain0->filter_chain_lock); |
| |
| tp_head = tcf_chain_dereference(chain0->filter_chain, chain0); |
| if (tp_head) |
| tcf_chain_head_change_item(item, tp_head); |
| |
| mutex_lock(&block->lock); |
| list_add(&item->list, &block->chain0.filter_chain_list); |
| mutex_unlock(&block->lock); |
| |
| mutex_unlock(&chain0->filter_chain_lock); |
| tcf_chain_put(chain0); |
| } |
| |
| return 0; |
| } |
| |
| static void |
| tcf_chain0_head_change_cb_del(struct tcf_block *block, |
| struct tcf_block_ext_info *ei) |
| { |
| struct tcf_filter_chain_list_item *item; |
| |
| mutex_lock(&block->lock); |
| list_for_each_entry(item, &block->chain0.filter_chain_list, list) { |
| if ((!ei->chain_head_change && !ei->chain_head_change_priv) || |
| (item->chain_head_change == ei->chain_head_change && |
| item->chain_head_change_priv == ei->chain_head_change_priv)) { |
| if (block->chain0.chain) |
| tcf_chain_head_change_item(item, NULL); |
| list_del(&item->list); |
| mutex_unlock(&block->lock); |
| |
| kfree(item); |
| return; |
| } |
| } |
| mutex_unlock(&block->lock); |
| WARN_ON(1); |
| } |
| |
| struct tcf_net { |
| spinlock_t idr_lock; /* Protects idr */ |
| struct idr idr; |
| }; |
| |
| static unsigned int tcf_net_id; |
| |
| static int tcf_block_insert(struct tcf_block *block, struct net *net, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_net *tn = net_generic(net, tcf_net_id); |
| int err; |
| |
| idr_preload(GFP_KERNEL); |
| spin_lock(&tn->idr_lock); |
| err = idr_alloc_u32(&tn->idr, block, &block->index, block->index, |
| GFP_NOWAIT); |
| spin_unlock(&tn->idr_lock); |
| idr_preload_end(); |
| |
| return err; |
| } |
| |
| static void tcf_block_remove(struct tcf_block *block, struct net *net) |
| { |
| struct tcf_net *tn = net_generic(net, tcf_net_id); |
| |
| spin_lock(&tn->idr_lock); |
| idr_remove(&tn->idr, block->index); |
| spin_unlock(&tn->idr_lock); |
| } |
| |
| static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q, |
| u32 block_index, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_block *block; |
| |
| block = kzalloc(sizeof(*block), GFP_KERNEL); |
| if (!block) { |
| NL_SET_ERR_MSG(extack, "Memory allocation for block failed"); |
| return ERR_PTR(-ENOMEM); |
| } |
| mutex_init(&block->lock); |
| mutex_init(&block->proto_destroy_lock); |
| init_rwsem(&block->cb_lock); |
| flow_block_init(&block->flow_block); |
| INIT_LIST_HEAD(&block->chain_list); |
| INIT_LIST_HEAD(&block->owner_list); |
| INIT_LIST_HEAD(&block->chain0.filter_chain_list); |
| |
| refcount_set(&block->refcnt, 1); |
| block->net = net; |
| block->index = block_index; |
| |
| /* Don't store q pointer for blocks which are shared */ |
| if (!tcf_block_shared(block)) |
| block->q = q; |
| return block; |
| } |
| |
| static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index) |
| { |
| struct tcf_net *tn = net_generic(net, tcf_net_id); |
| |
| return idr_find(&tn->idr, block_index); |
| } |
| |
| static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index) |
| { |
| struct tcf_block *block; |
| |
| rcu_read_lock(); |
| block = tcf_block_lookup(net, block_index); |
| if (block && !refcount_inc_not_zero(&block->refcnt)) |
| block = NULL; |
| rcu_read_unlock(); |
| |
| return block; |
| } |
| |
| static struct tcf_chain * |
| __tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain) |
| { |
| mutex_lock(&block->lock); |
| if (chain) |
| chain = list_is_last(&chain->list, &block->chain_list) ? |
| NULL : list_next_entry(chain, list); |
| else |
| chain = list_first_entry_or_null(&block->chain_list, |
| struct tcf_chain, list); |
| |
| /* skip all action-only chains */ |
| while (chain && tcf_chain_held_by_acts_only(chain)) |
| chain = list_is_last(&chain->list, &block->chain_list) ? |
| NULL : list_next_entry(chain, list); |
| |
| if (chain) |
| tcf_chain_hold(chain); |
| mutex_unlock(&block->lock); |
| |
| return chain; |
| } |
| |
| /* Function to be used by all clients that want to iterate over all chains on |
| * block. It properly obtains block->lock and takes reference to chain before |
| * returning it. Users of this function must be tolerant to concurrent chain |
| * insertion/deletion or ensure that no concurrent chain modification is |
| * possible. Note that all netlink dump callbacks cannot guarantee to provide |
| * consistent dump because rtnl lock is released each time skb is filled with |
| * data and sent to user-space. |
| */ |
| |
| struct tcf_chain * |
| tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain) |
| { |
| struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain); |
| |
| if (chain) |
| tcf_chain_put(chain); |
| |
| return chain_next; |
| } |
| EXPORT_SYMBOL(tcf_get_next_chain); |
| |
| static struct tcf_proto * |
| __tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp) |
| { |
| u32 prio = 0; |
| |
| ASSERT_RTNL(); |
| mutex_lock(&chain->filter_chain_lock); |
| |
| if (!tp) { |
| tp = tcf_chain_dereference(chain->filter_chain, chain); |
| } else if (tcf_proto_is_deleting(tp)) { |
| /* 'deleting' flag is set and chain->filter_chain_lock was |
| * unlocked, which means next pointer could be invalid. Restart |
| * search. |
| */ |
| prio = tp->prio + 1; |
| tp = tcf_chain_dereference(chain->filter_chain, chain); |
| |
| for (; tp; tp = tcf_chain_dereference(tp->next, chain)) |
| if (!tp->deleting && tp->prio >= prio) |
| break; |
| } else { |
| tp = tcf_chain_dereference(tp->next, chain); |
| } |
| |
| if (tp) |
| tcf_proto_get(tp); |
| |
| mutex_unlock(&chain->filter_chain_lock); |
| |
| return tp; |
| } |
| |
| /* Function to be used by all clients that want to iterate over all tp's on |
| * chain. Users of this function must be tolerant to concurrent tp |
| * insertion/deletion or ensure that no concurrent chain modification is |
| * possible. Note that all netlink dump callbacks cannot guarantee to provide |
| * consistent dump because rtnl lock is released each time skb is filled with |
| * data and sent to user-space. |
| */ |
| |
| struct tcf_proto * |
| tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp, |
| bool rtnl_held) |
| { |
| struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp); |
| |
| if (tp) |
| tcf_proto_put(tp, rtnl_held, NULL); |
| |
| return tp_next; |
| } |
| EXPORT_SYMBOL(tcf_get_next_proto); |
| |
| static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held) |
| { |
| struct tcf_chain *chain; |
| |
| /* Last reference to block. At this point chains cannot be added or |
| * removed concurrently. |
| */ |
| for (chain = tcf_get_next_chain(block, NULL); |
| chain; |
| chain = tcf_get_next_chain(block, chain)) { |
| tcf_chain_put_explicitly_created(chain); |
| tcf_chain_flush(chain, rtnl_held); |
| } |
| } |
| |
| /* Lookup Qdisc and increments its reference counter. |
| * Set parent, if necessary. |
| */ |
| |
| static int __tcf_qdisc_find(struct net *net, struct Qdisc **q, |
| u32 *parent, int ifindex, bool rtnl_held, |
| struct netlink_ext_ack *extack) |
| { |
| const struct Qdisc_class_ops *cops; |
| struct net_device *dev; |
| int err = 0; |
| |
| if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) |
| return 0; |
| |
| rcu_read_lock(); |
| |
| /* Find link */ |
| dev = dev_get_by_index_rcu(net, ifindex); |
| if (!dev) { |
| rcu_read_unlock(); |
| return -ENODEV; |
| } |
| |
| /* Find qdisc */ |
| if (!*parent) { |
| *q = dev->qdisc; |
| *parent = (*q)->handle; |
| } else { |
| *q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent)); |
| if (!*q) { |
| NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists"); |
| err = -EINVAL; |
| goto errout_rcu; |
| } |
| } |
| |
| *q = qdisc_refcount_inc_nz(*q); |
| if (!*q) { |
| NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists"); |
| err = -EINVAL; |
| goto errout_rcu; |
| } |
| |
| /* Is it classful? */ |
| cops = (*q)->ops->cl_ops; |
| if (!cops) { |
| NL_SET_ERR_MSG(extack, "Qdisc not classful"); |
| err = -EINVAL; |
| goto errout_qdisc; |
| } |
| |
| if (!cops->tcf_block) { |
| NL_SET_ERR_MSG(extack, "Class doesn't support blocks"); |
| err = -EOPNOTSUPP; |
| goto errout_qdisc; |
| } |
| |
| errout_rcu: |
| /* At this point we know that qdisc is not noop_qdisc, |
| * which means that qdisc holds a reference to net_device |
| * and we hold a reference to qdisc, so it is safe to release |
| * rcu read lock. |
| */ |
| rcu_read_unlock(); |
| return err; |
| |
| errout_qdisc: |
| rcu_read_unlock(); |
| |
| if (rtnl_held) |
| qdisc_put(*q); |
| else |
| qdisc_put_unlocked(*q); |
| *q = NULL; |
| |
| return err; |
| } |
| |
| static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl, |
| int ifindex, struct netlink_ext_ack *extack) |
| { |
| if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) |
| return 0; |
| |
| /* Do we search for filter, attached to class? */ |
| if (TC_H_MIN(parent)) { |
| const struct Qdisc_class_ops *cops = q->ops->cl_ops; |
| |
| *cl = cops->find(q, parent); |
| if (*cl == 0) { |
| NL_SET_ERR_MSG(extack, "Specified class doesn't exist"); |
| return -ENOENT; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q, |
| unsigned long cl, int ifindex, |
| u32 block_index, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_block *block; |
| |
| if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) { |
| block = tcf_block_refcnt_get(net, block_index); |
| if (!block) { |
| NL_SET_ERR_MSG(extack, "Block of given index was not found"); |
| return ERR_PTR(-EINVAL); |
| } |
| } else { |
| const struct Qdisc_class_ops *cops = q->ops->cl_ops; |
| |
| block = cops->tcf_block(q, cl, extack); |
| if (!block) |
| return ERR_PTR(-EINVAL); |
| |
| if (tcf_block_shared(block)) { |
| NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters"); |
| return ERR_PTR(-EOPNOTSUPP); |
| } |
| |
| /* Always take reference to block in order to support execution |
| * of rules update path of cls API without rtnl lock. Caller |
| * must release block when it is finished using it. 'if' block |
| * of this conditional obtain reference to block by calling |
| * tcf_block_refcnt_get(). |
| */ |
| refcount_inc(&block->refcnt); |
| } |
| |
| return block; |
| } |
| |
| static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q, |
| struct tcf_block_ext_info *ei, bool rtnl_held) |
| { |
| if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) { |
| /* Flushing/putting all chains will cause the block to be |
| * deallocated when last chain is freed. However, if chain_list |
| * is empty, block has to be manually deallocated. After block |
| * reference counter reached 0, it is no longer possible to |
| * increment it or add new chains to block. |
| */ |
| bool free_block = list_empty(&block->chain_list); |
| |
| mutex_unlock(&block->lock); |
| if (tcf_block_shared(block)) |
| tcf_block_remove(block, block->net); |
| |
| if (q) |
| tcf_block_offload_unbind(block, q, ei); |
| |
| if (free_block) |
| tcf_block_destroy(block); |
| else |
| tcf_block_flush_all_chains(block, rtnl_held); |
| } else if (q) { |
| tcf_block_offload_unbind(block, q, ei); |
| } |
| } |
| |
| static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held) |
| { |
| __tcf_block_put(block, NULL, NULL, rtnl_held); |
| } |
| |
| /* Find tcf block. |
| * Set q, parent, cl when appropriate. |
| */ |
| |
| static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q, |
| u32 *parent, unsigned long *cl, |
| int ifindex, u32 block_index, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_block *block; |
| int err = 0; |
| |
| ASSERT_RTNL(); |
| |
| err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack); |
| if (err) |
| goto errout; |
| |
| err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack); |
| if (err) |
| goto errout_qdisc; |
| |
| block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack); |
| if (IS_ERR(block)) { |
| err = PTR_ERR(block); |
| goto errout_qdisc; |
| } |
| |
| return block; |
| |
| errout_qdisc: |
| if (*q) |
| qdisc_put(*q); |
| errout: |
| *q = NULL; |
| return ERR_PTR(err); |
| } |
| |
| static void tcf_block_release(struct Qdisc *q, struct tcf_block *block, |
| bool rtnl_held) |
| { |
| if (!IS_ERR_OR_NULL(block)) |
| tcf_block_refcnt_put(block, rtnl_held); |
| |
| if (q) { |
| if (rtnl_held) |
| qdisc_put(q); |
| else |
| qdisc_put_unlocked(q); |
| } |
| } |
| |
| struct tcf_block_owner_item { |
| struct list_head list; |
| struct Qdisc *q; |
| enum flow_block_binder_type binder_type; |
| }; |
| |
| static void |
| tcf_block_owner_netif_keep_dst(struct tcf_block *block, |
| struct Qdisc *q, |
| enum flow_block_binder_type binder_type) |
| { |
| if (block->keep_dst && |
| binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS && |
| binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS) |
| netif_keep_dst(qdisc_dev(q)); |
| } |
| |
| void tcf_block_netif_keep_dst(struct tcf_block *block) |
| { |
| struct tcf_block_owner_item *item; |
| |
| block->keep_dst = true; |
| list_for_each_entry(item, &block->owner_list, list) |
| tcf_block_owner_netif_keep_dst(block, item->q, |
| item->binder_type); |
| } |
| EXPORT_SYMBOL(tcf_block_netif_keep_dst); |
| |
| static int tcf_block_owner_add(struct tcf_block *block, |
| struct Qdisc *q, |
| enum flow_block_binder_type binder_type) |
| { |
| struct tcf_block_owner_item *item; |
| |
| item = kmalloc(sizeof(*item), GFP_KERNEL); |
| if (!item) |
| return -ENOMEM; |
| item->q = q; |
| item->binder_type = binder_type; |
| list_add(&item->list, &block->owner_list); |
| return 0; |
| } |
| |
| static void tcf_block_owner_del(struct tcf_block *block, |
| struct Qdisc *q, |
| enum flow_block_binder_type binder_type) |
| { |
| struct tcf_block_owner_item *item; |
| |
| list_for_each_entry(item, &block->owner_list, list) { |
| if (item->q == q && item->binder_type == binder_type) { |
| list_del(&item->list); |
| kfree(item); |
| return; |
| } |
| } |
| WARN_ON(1); |
| } |
| |
| int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q, |
| struct tcf_block_ext_info *ei, |
| struct netlink_ext_ack *extack) |
| { |
| struct net *net = qdisc_net(q); |
| struct tcf_block *block = NULL; |
| int err; |
| |
| if (ei->block_index) |
| /* block_index not 0 means the shared block is requested */ |
| block = tcf_block_refcnt_get(net, ei->block_index); |
| |
| if (!block) { |
| block = tcf_block_create(net, q, ei->block_index, extack); |
| if (IS_ERR(block)) |
| return PTR_ERR(block); |
| if (tcf_block_shared(block)) { |
| err = tcf_block_insert(block, net, extack); |
| if (err) |
| goto err_block_insert; |
| } |
| } |
| |
| err = tcf_block_owner_add(block, q, ei->binder_type); |
| if (err) |
| goto err_block_owner_add; |
| |
| tcf_block_owner_netif_keep_dst(block, q, ei->binder_type); |
| |
| err = tcf_chain0_head_change_cb_add(block, ei, extack); |
| if (err) |
| goto err_chain0_head_change_cb_add; |
| |
| err = tcf_block_offload_bind(block, q, ei, extack); |
| if (err) |
| goto err_block_offload_bind; |
| |
| *p_block = block; |
| return 0; |
| |
| err_block_offload_bind: |
| tcf_chain0_head_change_cb_del(block, ei); |
| err_chain0_head_change_cb_add: |
| tcf_block_owner_del(block, q, ei->binder_type); |
| err_block_owner_add: |
| err_block_insert: |
| tcf_block_refcnt_put(block, true); |
| return err; |
| } |
| EXPORT_SYMBOL(tcf_block_get_ext); |
| |
| static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv) |
| { |
| struct tcf_proto __rcu **p_filter_chain = priv; |
| |
| rcu_assign_pointer(*p_filter_chain, tp_head); |
| } |
| |
| int tcf_block_get(struct tcf_block **p_block, |
| struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_block_ext_info ei = { |
| .chain_head_change = tcf_chain_head_change_dflt, |
| .chain_head_change_priv = p_filter_chain, |
| }; |
| |
| WARN_ON(!p_filter_chain); |
| return tcf_block_get_ext(p_block, q, &ei, extack); |
| } |
| EXPORT_SYMBOL(tcf_block_get); |
| |
| /* XXX: Standalone actions are not allowed to jump to any chain, and bound |
| * actions should be all removed after flushing. |
| */ |
| void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q, |
| struct tcf_block_ext_info *ei) |
| { |
| if (!block) |
| return; |
| tcf_chain0_head_change_cb_del(block, ei); |
| tcf_block_owner_del(block, q, ei->binder_type); |
| |
| __tcf_block_put(block, q, ei, true); |
| } |
| EXPORT_SYMBOL(tcf_block_put_ext); |
| |
| void tcf_block_put(struct tcf_block *block) |
| { |
| struct tcf_block_ext_info ei = {0, }; |
| |
| if (!block) |
| return; |
| tcf_block_put_ext(block, block->q, &ei); |
| } |
| |
| EXPORT_SYMBOL(tcf_block_put); |
| |
| static int |
| tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb, |
| void *cb_priv, bool add, bool offload_in_use, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_chain *chain, *chain_prev; |
| struct tcf_proto *tp, *tp_prev; |
| int err; |
| |
| lockdep_assert_held(&block->cb_lock); |
| |
| for (chain = __tcf_get_next_chain(block, NULL); |
| chain; |
| chain_prev = chain, |
| chain = __tcf_get_next_chain(block, chain), |
| tcf_chain_put(chain_prev)) { |
| for (tp = __tcf_get_next_proto(chain, NULL); tp; |
| tp_prev = tp, |
| tp = __tcf_get_next_proto(chain, tp), |
| tcf_proto_put(tp_prev, true, NULL)) { |
| if (tp->ops->reoffload) { |
| err = tp->ops->reoffload(tp, add, cb, cb_priv, |
| extack); |
| if (err && add) |
| goto err_playback_remove; |
| } else if (add && offload_in_use) { |
| err = -EOPNOTSUPP; |
| NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support"); |
| goto err_playback_remove; |
| } |
| } |
| } |
| |
| return 0; |
| |
| err_playback_remove: |
| tcf_proto_put(tp, true, NULL); |
| tcf_chain_put(chain); |
| tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use, |
| extack); |
| return err; |
| } |
| |
| static int tcf_block_bind(struct tcf_block *block, |
| struct flow_block_offload *bo) |
| { |
| struct flow_block_cb *block_cb, *next; |
| int err, i = 0; |
| |
| lockdep_assert_held(&block->cb_lock); |
| |
| list_for_each_entry(block_cb, &bo->cb_list, list) { |
| err = tcf_block_playback_offloads(block, block_cb->cb, |
| block_cb->cb_priv, true, |
| tcf_block_offload_in_use(block), |
| bo->extack); |
| if (err) |
| goto err_unroll; |
| if (!bo->unlocked_driver_cb) |
| block->lockeddevcnt++; |
| |
| i++; |
| } |
| list_splice(&bo->cb_list, &block->flow_block.cb_list); |
| |
| return 0; |
| |
| err_unroll: |
| list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) { |
| if (i-- > 0) { |
| list_del(&block_cb->list); |
| tcf_block_playback_offloads(block, block_cb->cb, |
| block_cb->cb_priv, false, |
| tcf_block_offload_in_use(block), |
| NULL); |
| if (!bo->unlocked_driver_cb) |
| block->lockeddevcnt--; |
| } |
| flow_block_cb_free(block_cb); |
| } |
| |
| return err; |
| } |
| |
| static void tcf_block_unbind(struct tcf_block *block, |
| struct flow_block_offload *bo) |
| { |
| struct flow_block_cb *block_cb, *next; |
| |
| lockdep_assert_held(&block->cb_lock); |
| |
| list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) { |
| tcf_block_playback_offloads(block, block_cb->cb, |
| block_cb->cb_priv, false, |
| tcf_block_offload_in_use(block), |
| NULL); |
| list_del(&block_cb->list); |
| flow_block_cb_free(block_cb); |
| if (!bo->unlocked_driver_cb) |
| block->lockeddevcnt--; |
| } |
| } |
| |
| static int tcf_block_setup(struct tcf_block *block, |
| struct flow_block_offload *bo) |
| { |
| int err; |
| |
| switch (bo->command) { |
| case FLOW_BLOCK_BIND: |
| err = tcf_block_bind(block, bo); |
| break; |
| case FLOW_BLOCK_UNBIND: |
| err = 0; |
| tcf_block_unbind(block, bo); |
| break; |
| default: |
| WARN_ON_ONCE(1); |
| err = -EOPNOTSUPP; |
| } |
| |
| return err; |
| } |
| |
| /* Main classifier routine: scans classifier chain attached |
| * to this qdisc, (optionally) tests for protocol and asks |
| * specific classifiers. |
| */ |
| static inline int __tcf_classify(struct sk_buff *skb, |
| const struct tcf_proto *tp, |
| const struct tcf_proto *orig_tp, |
| struct tcf_result *res, |
| bool compat_mode, |
| u32 *last_executed_chain) |
| { |
| #ifdef CONFIG_NET_CLS_ACT |
| const int max_reclassify_loop = 4; |
| const struct tcf_proto *first_tp; |
| int limit = 0; |
| |
| reclassify: |
| #endif |
| for (; tp; tp = rcu_dereference_bh(tp->next)) { |
| __be16 protocol = skb_protocol(skb, false); |
| int err; |
| |
| if (tp->protocol != protocol && |
| tp->protocol != htons(ETH_P_ALL)) |
| continue; |
| |
| err = tp->classify(skb, tp, res); |
| #ifdef CONFIG_NET_CLS_ACT |
| if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) { |
| first_tp = orig_tp; |
| *last_executed_chain = first_tp->chain->index; |
| goto reset; |
| } else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) { |
| first_tp = res->goto_tp; |
| *last_executed_chain = err & TC_ACT_EXT_VAL_MASK; |
| goto reset; |
| } |
| #endif |
| if (err >= 0) |
| return err; |
| } |
| |
| return TC_ACT_UNSPEC; /* signal: continue lookup */ |
| #ifdef CONFIG_NET_CLS_ACT |
| reset: |
| if (unlikely(limit++ >= max_reclassify_loop)) { |
| net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n", |
| tp->chain->block->index, |
| tp->prio & 0xffff, |
| ntohs(tp->protocol)); |
| return TC_ACT_SHOT; |
| } |
| |
| tp = first_tp; |
| goto reclassify; |
| #endif |
| } |
| |
| int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp, |
| struct tcf_result *res, bool compat_mode) |
| { |
| u32 last_executed_chain = 0; |
| |
| return __tcf_classify(skb, tp, tp, res, compat_mode, |
| &last_executed_chain); |
| } |
| EXPORT_SYMBOL(tcf_classify); |
| |
| int tcf_classify_ingress(struct sk_buff *skb, |
| const struct tcf_block *ingress_block, |
| const struct tcf_proto *tp, |
| struct tcf_result *res, bool compat_mode) |
| { |
| #if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT) |
| u32 last_executed_chain = 0; |
| |
| return __tcf_classify(skb, tp, tp, res, compat_mode, |
| &last_executed_chain); |
| #else |
| u32 last_executed_chain = tp ? tp->chain->index : 0; |
| const struct tcf_proto *orig_tp = tp; |
| struct tc_skb_ext *ext; |
| int ret; |
| |
| ext = skb_ext_find(skb, TC_SKB_EXT); |
| |
| if (ext && ext->chain) { |
| struct tcf_chain *fchain; |
| |
| fchain = tcf_chain_lookup_rcu(ingress_block, ext->chain); |
| if (!fchain) |
| return TC_ACT_SHOT; |
| |
| /* Consume, so cloned/redirect skbs won't inherit ext */ |
| skb_ext_del(skb, TC_SKB_EXT); |
| |
| tp = rcu_dereference_bh(fchain->filter_chain); |
| last_executed_chain = fchain->index; |
| } |
| |
| ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode, |
| &last_executed_chain); |
| |
| /* If we missed on some chain */ |
| if (ret == TC_ACT_UNSPEC && last_executed_chain) { |
| ext = skb_ext_add(skb, TC_SKB_EXT); |
| if (WARN_ON_ONCE(!ext)) |
| return TC_ACT_SHOT; |
| ext->chain = last_executed_chain; |
| ext->mru = qdisc_skb_cb(skb)->mru; |
| } |
| |
| return ret; |
| #endif |
| } |
| EXPORT_SYMBOL(tcf_classify_ingress); |
| |
| struct tcf_chain_info { |
| struct tcf_proto __rcu **pprev; |
| struct tcf_proto __rcu *next; |
| }; |
| |
| static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain, |
| struct tcf_chain_info *chain_info) |
| { |
| return tcf_chain_dereference(*chain_info->pprev, chain); |
| } |
| |
| static int tcf_chain_tp_insert(struct tcf_chain *chain, |
| struct tcf_chain_info *chain_info, |
| struct tcf_proto *tp) |
| { |
| if (chain->flushing) |
| return -EAGAIN; |
| |
| if (*chain_info->pprev == chain->filter_chain) |
| tcf_chain0_head_change(chain, tp); |
| tcf_proto_get(tp); |
| RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info)); |
| rcu_assign_pointer(*chain_info->pprev, tp); |
| |
| return 0; |
| } |
| |
| static void tcf_chain_tp_remove(struct tcf_chain *chain, |
| struct tcf_chain_info *chain_info, |
| struct tcf_proto *tp) |
| { |
| struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain); |
| |
| tcf_proto_mark_delete(tp); |
| if (tp == chain->filter_chain) |
| tcf_chain0_head_change(chain, next); |
| RCU_INIT_POINTER(*chain_info->pprev, next); |
| } |
| |
| static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain, |
| struct tcf_chain_info *chain_info, |
| u32 protocol, u32 prio, |
| bool prio_allocate); |
| |
| /* Try to insert new proto. |
| * If proto with specified priority already exists, free new proto |
| * and return existing one. |
| */ |
| |
| static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain, |
| struct tcf_proto *tp_new, |
| u32 protocol, u32 prio, |
| bool rtnl_held) |
| { |
| struct tcf_chain_info chain_info; |
| struct tcf_proto *tp; |
| int err = 0; |
| |
| mutex_lock(&chain->filter_chain_lock); |
| |
| if (tcf_proto_exists_destroying(chain, tp_new)) { |
| mutex_unlock(&chain->filter_chain_lock); |
| tcf_proto_destroy(tp_new, rtnl_held, false, NULL); |
| return ERR_PTR(-EAGAIN); |
| } |
| |
| tp = tcf_chain_tp_find(chain, &chain_info, |
| protocol, prio, false); |
| if (!tp) |
| err = tcf_chain_tp_insert(chain, &chain_info, tp_new); |
| mutex_unlock(&chain->filter_chain_lock); |
| |
| if (tp) { |
| tcf_proto_destroy(tp_new, rtnl_held, false, NULL); |
| tp_new = tp; |
| } else if (err) { |
| tcf_proto_destroy(tp_new, rtnl_held, false, NULL); |
| tp_new = ERR_PTR(err); |
| } |
| |
| return tp_new; |
| } |
| |
| static void tcf_chain_tp_delete_empty(struct tcf_chain *chain, |
| struct tcf_proto *tp, bool rtnl_held, |
| struct netlink_ext_ack *extack) |
| { |
| struct tcf_chain_info chain_info; |
| struct tcf_proto *tp_iter; |
| struct tcf_proto **pprev; |
| struct tcf_proto *next; |
| |
| mutex_lock(&chain->filter_chain_lock); |
| |
| /* Atomically find and remove tp from chain. */ |
| for (pprev = &chain->filter_chain; |
| (tp_iter = tcf_chain_dereference(*pprev, chain)); |
| pprev = &tp_iter->next) { |
| if (tp_iter == tp) { |
| chain_info.pprev = pprev; |
| chain_info.next = tp_iter->next; |
| WARN_ON(tp_iter->deleting); |
| break; |
| } |
| } |
| /* Verify that tp still exists and no new filters were inserted |
| * concurrently. |
| * Mark tp for deletion if it is empty. |
| */ |
| if (!tp_iter || !tcf_proto_check_delete(tp)) { |
| mutex_unlock(&chain->filter_chain_lock); |
| return; |
| } |
| |
| tcf_proto_signal_destroying(chain, tp); |
| next = tcf_chain_dereference(chain_info.next, chain); |
| if (tp == chain->filter_chain) |
| tcf_chain0_head_change(chain, next); |
| RCU_INIT_POINTER(*chain_info.pprev, next); |
| mutex_unlock(&chain->filter_chain_lock); |
| |
| tcf_proto_put(tp, rtnl_held, extack); |
| } |
| |
| static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain, |
| struct tcf_chain_info *chain_info, |
| u32 protocol, u32 prio, |
| bool prio_allocate) |
| { |
| struct tcf_proto **pprev; |
| struct tcf_proto *tp; |
| |
| /* Check the chain for existence of proto-tcf with this priority */ |
| for (pprev = &chain->filter_chain; |
| (tp = tcf_chain_dereference(*pprev, chain)); |
| pprev = &tp->next) { |
| if (tp->prio >= prio) { |
| if (tp->prio == prio) { |
| if (prio_allocate || |
| (tp->protocol != protocol && protocol)) |
| return ERR_PTR(-EINVAL); |
| } else { |
| tp = NULL; |
| } |
| break; |
| } |
| } |
| chain_info->pprev = pprev; |
| if (tp) { |
| chain_info->next = tp->next; |
| tcf_proto_get(tp); |
| } else { |
| chain_info->next = NULL; |
| } |
| return tp; |
| } |
| |
| static int tcf_fill_node(struct net *net, struct sk_buff *skb, |
| struct tcf_proto *tp, struct tcf_block *block, |
| struct Qdisc *q, u32 parent, void *fh, |
| u32 portid, u32 seq, u16 flags, int event, |
| bool terse_dump, bool rtnl_held) |
| { |
| struct tcmsg *tcm; |
| struct nlmsghdr *nlh; |
| unsigned char *b = skb_tail_pointer(skb); |
| |
| nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); |
| if (!nlh) |
| goto out_nlmsg_trim; |
| tcm = nlmsg_data(nlh); |
| tcm->tcm_family = AF_UNSPEC; |
| tcm->tcm__pad1 = 0; |
| tcm->tcm__pad2 = 0; |
| if (q) { |
| tcm->tcm_ifindex = qdisc_dev(q)->ifindex; |
| tcm->tcm_parent = parent; |
| } else { |
| tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK; |
| tcm->tcm_block_index = block->index; |
| } |
| tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol); |
| if (nla_put_string(skb, TCA_KIND, tp->ops->kind)) |
| goto nla_put_failure; |
| if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index)) |
| goto nla_put_failure; |
| if (!fh) { |
| tcm->tcm_handle = 0; |
| } else if (terse_dump) { |
| if (tp->ops->terse_dump) { |
| if (tp->ops->terse_dump(net, tp, fh, skb, tcm, |
| rtnl_held) < 0) |
| goto nla_put_failure; |
| } else { |
| goto cls_op_not_supp; |
| } |
| } else { |
| if (tp->ops->dump && |
| tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0) |
| goto nla_put_failure; |
| } |
| nlh->nlmsg_len = skb_tail_pointer(skb) - b; |
| return skb->len; |
| |
| out_nlmsg_trim: |
| nla_put_failure: |
| cls_op_not_supp: |
| nlmsg_trim(skb, b); |
| return -1; |
| } |
| |
| static int tfilter_notify(struct net *net, struct sk_buff *oskb, |
| struct nlmsghdr *n, struct tcf_proto *tp, |
| struct tcf_block *block, struct Qdisc *q, |
| u32 parent, void *fh, int event, bool unicast, |
| bool rtnl_held) |
| { |
| struct sk_buff *skb; |
| u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; |
| int err = 0; |
| |
| skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
| if (!skb) |
| return -ENOBUFS; |
| |
| if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid, |
| n->nlmsg_seq, n->nlmsg_flags, event, |
| false, rtnl_held) <= 0) { |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| |
| if (unicast) |
| err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); |
| else |
| err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, |
| n->nlmsg_flags & NLM_F_ECHO); |
| |
| if (err > 0) |
| err = 0; |
| return err; |
| } |
| |
| static int tfilter_del_notify(struct net *net, struct sk_buff *oskb, |
| struct nlmsghdr *n, struct tcf_proto *tp, |
| struct tcf_block *block, struct Qdisc *q, |
| u32 parent, void *fh, bool unicast, bool *last, |
| bool rtnl_held, struct netlink_ext_ack *extack) |
| { |
| struct sk_buff *skb; |
| u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; |
| int err; |
| |
| skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
| if (!skb) |
| return -ENOBUFS; |
| |
| if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid, |
| n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER, |
| false, rtnl_held) <= 0) { |
| NL_SET_ERR_MSG(extack, "Failed to build del event notification"); |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| |
| err = tp->ops->delete(tp, fh, last, rtnl_held, extack); |
| if (err) { |
| kfree_skb(skb); |
| return err; |
| } |
| |
| if (unicast) |
| err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); |
| else |
| err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, |
| n->nlmsg_flags & NLM_F_ECHO); |
| if (err < 0) |
| NL_SET_ERR_MSG(extack, "Failed to send filter delete notification"); |
| |
| if (err > 0) |
| err = 0; |
| return err; |
| } |
| |
| static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb, |
| struct tcf_block *block, struct Qdisc *q, |
| u32 parent, struct nlmsghdr *n, |
| struct tcf_chain *chain, int event, |
| bool rtnl_held) |
| { |
| struct tcf_proto *tp; |
| |
| for (tp = tcf_get_next_proto(chain, NULL, rtnl_held); |
| tp; tp = tcf_get_next_proto(chain, tp, rtnl_held)) |
| tfilter_notify(net, oskb, n, tp, block, |
| q, parent, NULL, event, false, rtnl_held); |
| } |
| |
| static void tfilter_put(struct tcf_proto *tp, void *fh) |
| { |
| if (tp->ops->put && fh) |
| tp->ops->put(tp, fh); |
| } |
| |
| static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n, |
| struct netlink_ext_ack *extack) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct nlattr *tca[TCA_MAX + 1]; |
| char name[IFNAMSIZ]; |
| struct tcmsg *t; |
| u32 protocol; |
| u32 prio; |
| bool prio_allocate; |
| u32 parent; |
| u32 chain_index; |
| struct Qdisc *q = NULL; |
| struct tcf_chain_info chain_info; |
| struct tcf_chain *chain = NULL; |
| struct tcf_block *block; |
| struct tcf_proto *tp; |
| unsigned long cl; |
| void *fh; |
| int err; |
| int tp_created; |
| bool rtnl_held = false; |
| |
| if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) |
| return -EPERM; |
| |
| replay: |
| tp_created = 0; |
| |
| err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, |
| rtm_tca_policy, extack); |
| if (err < 0) |
| return err; |
| |
| t = nlmsg_data(n); |
| protocol = TC_H_MIN(t->tcm_info); |
| prio = TC_H_MAJ(t->tcm_info); |
| prio_allocate = false; |
| parent = t->tcm_parent; |
| tp = NULL; |
| cl = 0; |
| block = NULL; |
| |
| if (prio == 0) { |
| /* If no priority is provided by the user, |
| * we allocate one. |
| */ |
| if (n->nlmsg_flags & NLM_F_CREATE) { |
| prio = TC_H_MAKE(0x80000000U, 0U); |
| prio_allocate = true; |
| } else { |
| NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero"); |
| return -ENOENT; |
| } |
| } |
| |
| /* Find head of filter chain. */ |
| |
| err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); |
| if (err) |
| return err; |
| |
| if (tcf_proto_check_kind(tca[TCA_KIND], name)) { |
| NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); |
| err = -EINVAL; |
| goto errout; |
| } |
| |
| /* Take rtnl mutex if rtnl_held was set to true on previous iteration, |
| * block is shared (no qdisc found), qdisc is not unlocked, classifier |
| * type is not specified, classifier is not unlocked. |
| */ |
| if (rtnl_held || |
| (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || |
| !tcf_proto_is_unlocked(name)) { |
| rtnl_held = true; |
| rtnl_lock(); |
| } |
| |
| err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); |
| if (err) |
| goto errout; |
| |
| block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, |
| extack); |
| if (IS_ERR(block)) { |
| err = PTR_ERR(block); |
| goto errout; |
| } |
| block->classid = parent; |
| |
| chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; |
| if (chain_index > TC_ACT_EXT_VAL_MASK) { |
| NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); |
| err = -EINVAL; |
| goto errout; |
| } |
| chain = tcf_chain_get(block, chain_index, true); |
| if (!chain) { |
| NL_SET_ERR_MSG(extack, "Cannot create specified filter chain"); |
| err = -ENOMEM; |
| goto errout; |
| } |
| |
| mutex_lock(&chain->filter_chain_lock); |
| tp = tcf_chain_tp_find(chain, &chain_info, protocol, |
| prio, prio_allocate); |
| if (IS_ERR(tp)) { |
| NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); |
| err = PTR_ERR(tp); |
| goto errout_locked; |
| } |
| |
| if (tp == NULL) { |
| struct tcf_proto *tp_new = NULL; |
| |
| if (chain->flushing) { |
| err = -EAGAIN; |
| goto errout_locked; |
| } |
| |
| /* Proto-tcf does not exist, create new one */ |
| |
| if (tca[TCA_KIND] == NULL || !protocol) { |
| NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified"); |
| err = -EINVAL; |
| goto errout_locked; |
| } |
| |
| if (!(n->nlmsg_flags & NLM_F_CREATE)) { |
| NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter"); |
| err = -ENOENT; |
| goto errout_locked; |
| } |
| |
| if (prio_allocate) |
| prio = tcf_auto_prio(tcf_chain_tp_prev(chain, |
| &chain_info)); |
| |
| mutex_unlock(&chain->filter_chain_lock); |
| tp_new = tcf_proto_create(name, protocol, prio, chain, |
| rtnl_held, extack); |
| if (IS_ERR(tp_new)) { |
| err = PTR_ERR(tp_new); |
| goto errout_tp; |
| } |
| |
| tp_created = 1; |
| tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio, |
| rtnl_held); |
| if (IS_ERR(tp)) { |
| err = PTR_ERR(tp); |
| goto errout_tp; |
| } |
| } else { |
| mutex_unlock(&chain->filter_chain_lock); |
| } |
| |
| if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { |
| NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); |
| err = -EINVAL; |
| goto errout; |
| } |
| |
| fh = tp->ops->get(tp, t->tcm_handle); |
| |
| if (!fh) { |
| if (!(n->nlmsg_flags & NLM_F_CREATE)) { |
| NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter"); |
| err = -ENOENT; |
| goto errout; |
| } |
| } else if (n->nlmsg_flags & NLM_F_EXCL) { |
| tfilter_put(tp, fh); |
| NL_SET_ERR_MSG(extack, "Filter already exists"); |
| err = -EEXIST; |
| goto errout; |
| } |
| |
| if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) { |
| NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind"); |
| err = -EINVAL; |
| goto errout; |
| } |
| |
| err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh, |
| n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE, |
| rtnl_held, extack); |
| if (err == 0) { |
| tfilter_notify(net, skb, n, tp, block, q, parent, fh, |
| RTM_NEWTFILTER, false, rtnl_held); |
| tfilter_put(tp, fh); |
| /* q pointer is NULL for shared blocks */ |
| if (q) |
| q->flags &= ~TCQ_F_CAN_BYPASS; |
| } |
| |
| errout: |
| if (err && tp_created) |
| tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL); |
| errout_tp: |
| if (chain) { |
| if (tp && !IS_ERR(tp)) |
| tcf_proto_put(tp, rtnl_held, NULL); |
| if (!tp_created) |
| tcf_chain_put(chain); |
| } |
| tcf_block_release(q, block, rtnl_held); |
| |
| if (rtnl_held) |
| rtnl_unlock(); |
| |
| if (err == -EAGAIN) { |
| /* Take rtnl lock in case EAGAIN is caused by concurrent flush |
| * of target chain. |
| */ |
| rtnl_held = true; |
| /* Replay the request. */ |
| goto replay; |
| } |
| return err; |
| |
| errout_locked: |
| mutex_unlock(&chain->filter_chain_lock); |
| goto errout; |
| } |
| |
| static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n, |
| struct netlink_ext_ack *extack) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct nlattr *tca[TCA_MAX + 1]; |
| char name[IFNAMSIZ]; |
| struct tcmsg *t; |
| u32 protocol; |
| u32 prio; |
| u32 parent; |
| u32 chain_index; |
| struct Qdisc *q = NULL; |
| struct tcf_chain_info chain_info; |
| struct tcf_chain *chain = NULL; |
| struct tcf_block *block = NULL; |
| struct tcf_proto *tp = NULL; |
| unsigned long cl = 0; |
| void *fh = NULL; |
| int err; |
| bool rtnl_held = false; |
| |
| if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) |
| return -EPERM; |
| |
| err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, |
| rtm_tca_policy, extack); |
| if (err < 0) |
| return err; |
| |
| t = nlmsg_data(n); |
| protocol = TC_H_MIN(t->tcm_info); |
| prio = TC_H_MAJ(t->tcm_info); |
| parent = t->tcm_parent; |
| |
| if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) { |
| NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set"); |
| return -ENOENT; |
| } |
| |
| /* Find head of filter chain. */ |
| |
| err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); |
| if (err) |
| return err; |
| |
| if (tcf_proto_check_kind(tca[TCA_KIND], name)) { |
| NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); |
| err = -EINVAL; |
| goto errout; |
| } |
| /* Take rtnl mutex if flushing whole chain, block is shared (no qdisc |
| * found), qdisc is not unlocked, classifier type is not specified, |
| * classifier is not unlocked. |
| */ |
| if (!prio || |
| (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || |
| !tcf_proto_is_unlocked(name)) { |
| rtnl_held = true; |
| rtnl_lock(); |
| } |
| |
| err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); |
| if (err) |
| goto errout; |
| |
| block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, |
| extack); |
| if (IS_ERR(block)) { |
| err = PTR_ERR(block); |
| goto errout; |
| } |
| |
| chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; |
| if (chain_index > TC_ACT_EXT_VAL_MASK) { |
| NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); |
| err = -EINVAL; |
| goto errout; |
| } |
| chain = tcf_chain_get(block, chain_index, false); |
| if (!chain) { |
| /* User requested flush on non-existent chain. Nothing to do, |
| * so just return success. |
| */ |
| if (prio == 0) { |
| err = 0; |
| goto errout; |
| } |
| NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); |
| err = -ENOENT; |
| goto errout; |
| } |
| |
| if (prio == 0) { |
| tfilter_notify_chain(net, skb, block, q, parent, n, |
| chain, RTM_DELTFILTER, rtnl_held); |
| tcf_chain_flush(chain, rtnl_held); |
| err = 0; |
| goto errout; |
| } |
| |
| mutex_lock(&chain->filter_chain_lock); |
| tp = tcf_chain_tp_find(chain, &chain_info, protocol, |
| prio, false); |
| if (!tp || IS_ERR(tp)) { |
| NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); |
| err = tp ? PTR_ERR(tp) : -ENOENT; |
| goto errout_locked; |
| } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { |
| NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); |
| err = -EINVAL; |
| goto errout_locked; |
| } else if (t->tcm_handle == 0) { |
| tcf_proto_signal_destroying(chain, tp); |
| tcf_chain_tp_remove(chain, &chain_info, tp); |
| mutex_unlock(&chain->filter_chain_lock); |
| |
| tcf_proto_put(tp, rtnl_held, NULL); |
| tfilter_notify(net, skb, n, tp, block, q, parent, fh, |
| RTM_DELTFILTER, false, rtnl_held); |
| err = 0; |
| goto errout; |
| } |
| mutex_unlock(&chain->filter_chain_lock); |
| |
| fh = tp->ops->get(tp, t->tcm_handle); |
| |
| if (!fh) { |
| NL_SET_ERR_MSG(extack, "Specified filter handle not found"); |
| err = -ENOENT; |
| } else { |
| bool last; |
| |
| err = tfilter_del_notify(net, skb, n, tp, block, |
| q, parent, fh, false, &last, |
| rtnl_held, extack); |
| |
| if (err) |
| goto errout; |
| if (last) |
| tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack); |
| } |
| |
| errout: |
| if (chain) { |
| if (tp && !IS_ERR(tp)) |
| tcf_proto_put(tp, rtnl_held, NULL); |
| tcf_chain_put(chain); |
| } |
| tcf_block_release(q, block, rtnl_held); |
| |
| if (rtnl_held) |
| rtnl_unlock(); |
| |
| return err; |
| |
| errout_locked: |
| mutex_unlock(&chain->filter_chain_lock); |
| goto errout; |
| } |
| |
| static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n, |
| struct netlink_ext_ack *extack) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct nlattr *tca[TCA_MAX + 1]; |
| char name[IFNAMSIZ]; |
| struct tcmsg *t; |
| u32 protocol; |
| u32 prio; |
| u32 parent; |
| u32 chain_index; |
| struct Qdisc *q = NULL; |
| struct tcf_chain_info chain_info; |
| struct tcf_chain *chain = NULL; |
| struct tcf_block *block = NULL; |
| struct tcf_proto *tp = NULL; |
| unsigned long cl = 0; |
| void *fh = NULL; |
| int err; |
| bool rtnl_held = false; |
| |
| err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, |
| rtm_tca_policy, extack); |
| if (err < 0) |
| return err; |
| |
| t = nlmsg_data(n); |
| protocol = TC_H_MIN(t->tcm_info); |
| prio = TC_H_MAJ(t->tcm_info); |
| parent = t->tcm_parent; |
| |
| if (prio == 0) { |
| NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero"); |
| return -ENOENT; |
| } |
| |
| /* Find head of filter chain. */ |
| |
| err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack); |
| if (err) |
| return err; |
| |
| if (tcf_proto_check_kind(tca[TCA_KIND], name)) { |
| NL_SET_ERR_MSG(extack, "Specified TC filter name too long"); |
| err = -EINVAL; |
| goto errout; |
| } |
| /* Take rtnl mutex if block is shared (no qdisc found), qdisc is not |
| * unlocked, classifier type is not specified, classifier is not |
| * unlocked. |
| */ |
| if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) || |
| !tcf_proto_is_unlocked(name)) { |
| rtnl_held = true; |
| rtnl_lock(); |
| } |
| |
| err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack); |
| if (err) |
| goto errout; |
| |
| block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index, |
| extack); |
| if (IS_ERR(block)) { |
| err = PTR_ERR(block); |
| goto errout; |
| } |
| |
| chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; |
| if (chain_index > TC_ACT_EXT_VAL_MASK) { |
| NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); |
| err = -EINVAL; |
| goto errout; |
| } |
| chain = tcf_chain_get(block, chain_index, false); |
| if (!chain) { |
| NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); |
| err = -EINVAL; |
| goto errout; |
| } |
| |
| mutex_lock(&chain->filter_chain_lock); |
| tp = tcf_chain_tp_find(chain, &chain_info, protocol, |
| prio, false); |
| mutex_unlock(&chain->filter_chain_lock); |
| if (!tp || IS_ERR(tp)) { |
| NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found"); |
| err = tp ? PTR_ERR(tp) : -ENOENT; |
| goto errout; |
| } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) { |
| NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one"); |
| err = -EINVAL; |
| goto errout; |
| } |
| |
| fh = tp->ops->get(tp, t->tcm_handle); |
| |
| if (!fh) { |
| NL_SET_ERR_MSG(extack, "Specified filter handle not found"); |
| err = -ENOENT; |
| } else { |
| err = tfilter_notify(net, skb, n, tp, block, q, parent, |
| fh, RTM_NEWTFILTER, true, rtnl_held); |
| if (err < 0) |
| NL_SET_ERR_MSG(extack, "Failed to send filter notify message"); |
| } |
| |
| tfilter_put(tp, fh); |
| errout: |
| if (chain) { |
| if (tp && !IS_ERR(tp)) |
| tcf_proto_put(tp, rtnl_held, NULL); |
| tcf_chain_put(chain); |
| } |
| tcf_block_release(q, block, rtnl_held); |
| |
| if (rtnl_held) |
| rtnl_unlock(); |
| |
| return err; |
| } |
| |
| struct tcf_dump_args { |
| struct tcf_walker w; |
| struct sk_buff *skb; |
| struct netlink_callback *cb; |
| struct tcf_block *block; |
| struct Qdisc *q; |
| u32 parent; |
| bool terse_dump; |
| }; |
| |
| static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg) |
| { |
| struct tcf_dump_args *a = (void *)arg; |
| struct net *net = sock_net(a->skb->sk); |
| |
| return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent, |
| n, NETLINK_CB(a->cb->skb).portid, |
| a->cb->nlh->nlmsg_seq, NLM_F_MULTI, |
| RTM_NEWTFILTER, a->terse_dump, true); |
| } |
| |
| static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent, |
| struct sk_buff *skb, struct netlink_callback *cb, |
| long index_start, long *p_index, bool terse) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct tcf_block *block = chain->block; |
| struct tcmsg *tcm = nlmsg_data(cb->nlh); |
| struct tcf_proto *tp, *tp_prev; |
| struct tcf_dump_args arg; |
| |
| for (tp = __tcf_get_next_proto(chain, NULL); |
| tp; |
| tp_prev = tp, |
| tp = __tcf_get_next_proto(chain, tp), |
| tcf_proto_put(tp_prev, true, NULL), |
| (*p_index)++) { |
| if (*p_index < index_start) |
| continue; |
| if (TC_H_MAJ(tcm->tcm_info) && |
| TC_H_MAJ(tcm->tcm_info) != tp->prio) |
| continue; |
| if (TC_H_MIN(tcm->tcm_info) && |
| TC_H_MIN(tcm->tcm_info) != tp->protocol) |
| continue; |
| if (*p_index > index_start) |
| memset(&cb->args[1], 0, |
| sizeof(cb->args) - sizeof(cb->args[0])); |
| if (cb->args[1] == 0) { |
| if (tcf_fill_node(net, skb, tp, block, q, parent, NULL, |
| NETLINK_CB(cb->skb).portid, |
| cb->nlh->nlmsg_seq, NLM_F_MULTI, |
| RTM_NEWTFILTER, false, true) <= 0) |
| goto errout; |
| cb->args[1] = 1; |
| } |
| if (!tp->ops->walk) |
| continue; |
| arg.w.fn = tcf_node_dump; |
| arg.skb = skb; |
| arg.cb = cb; |
| arg.block = block; |
| arg.q = q; |
| arg.parent = parent; |
| arg.w.stop = 0; |
| arg.w.skip = cb->args[1] - 1; |
| arg.w.count = 0; |
| arg.w.cookie = cb->args[2]; |
| arg.terse_dump = terse; |
| tp->ops->walk(tp, &arg.w, true); |
| cb->args[2] = arg.w.cookie; |
| cb->args[1] = arg.w.count + 1; |
| if (arg.w.stop) |
| goto errout; |
| } |
| return true; |
| |
| errout: |
| tcf_proto_put(tp, true, NULL); |
| return false; |
| } |
| |
| static const struct nla_policy tcf_tfilter_dump_policy[TCA_MAX + 1] = { |
| [TCA_DUMP_FLAGS] = NLA_POLICY_BITFIELD32(TCA_DUMP_FLAGS_TERSE), |
| }; |
| |
| /* called with RTNL */ |
| static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| struct tcf_chain *chain, *chain_prev; |
| struct net *net = sock_net(skb->sk); |
| struct nlattr *tca[TCA_MAX + 1]; |
| struct Qdisc *q = NULL; |
| struct tcf_block *block; |
| struct tcmsg *tcm = nlmsg_data(cb->nlh); |
| bool terse_dump = false; |
| long index_start; |
| long index; |
| u32 parent; |
| int err; |
| |
| if (nlmsg_len(cb->nlh) < sizeof(*tcm)) |
| return skb->len; |
| |
| err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX, |
| tcf_tfilter_dump_policy, cb->extack); |
| if (err) |
| return err; |
| |
| if (tca[TCA_DUMP_FLAGS]) { |
| struct nla_bitfield32 flags = |
| nla_get_bitfield32(tca[TCA_DUMP_FLAGS]); |
| |
| terse_dump = flags.value & TCA_DUMP_FLAGS_TERSE; |
| } |
| |
| if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) { |
| block = tcf_block_refcnt_get(net, tcm->tcm_block_index); |
| if (!block) |
| goto out; |
| /* If we work with block index, q is NULL and parent value |
| * will never be used in the following code. The check |
| * in tcf_fill_node prevents it. However, compiler does not |
| * see that far, so set parent to zero to silence the warning |
| * about parent being uninitialized. |
| */ |
| parent = 0; |
| } else { |
| const struct Qdisc_class_ops *cops; |
| struct net_device *dev; |
| unsigned long cl = 0; |
| |
| dev = __dev_get_by_index(net, tcm->tcm_ifindex); |
| if (!dev) |
| return skb->len; |
| |
| parent = tcm->tcm_parent; |
| if (!parent) |
| q = dev->qdisc; |
| else |
| q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); |
| if (!q) |
| goto out; |
| cops = q->ops->cl_ops; |
| if (!cops) |
| goto out; |
| if (!cops->tcf_block) |
| goto out; |
| if (TC_H_MIN(tcm->tcm_parent)) { |
| cl = cops->find(q, tcm->tcm_parent); |
| if (cl == 0) |
| goto out; |
| } |
| block = cops->tcf_block(q, cl, NULL); |
| if (!block) |
| goto out; |
| parent = block->classid; |
| if (tcf_block_shared(block)) |
| q = NULL; |
| } |
| |
| index_start = cb->args[0]; |
| index = 0; |
| |
| for (chain = __tcf_get_next_chain(block, NULL); |
| chain; |
| chain_prev = chain, |
| chain = __tcf_get_next_chain(block, chain), |
| tcf_chain_put(chain_prev)) { |
| if (tca[TCA_CHAIN] && |
| nla_get_u32(tca[TCA_CHAIN]) != chain->index) |
| continue; |
| if (!tcf_chain_dump(chain, q, parent, skb, cb, |
| index_start, &index, terse_dump)) { |
| tcf_chain_put(chain); |
| err = -EMSGSIZE; |
| break; |
| } |
| } |
| |
| if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) |
| tcf_block_refcnt_put(block, true); |
| cb->args[0] = index; |
| |
| out: |
| /* If we did no progress, the error (EMSGSIZE) is real */ |
| if (skb->len == 0 && err) |
| return err; |
| return skb->len; |
| } |
| |
| static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops, |
| void *tmplt_priv, u32 chain_index, |
| struct net *net, struct sk_buff *skb, |
| struct tcf_block *block, |
| u32 portid, u32 seq, u16 flags, int event) |
| { |
| unsigned char *b = skb_tail_pointer(skb); |
| const struct tcf_proto_ops *ops; |
| struct nlmsghdr *nlh; |
| struct tcmsg *tcm; |
| void *priv; |
| |
| ops = tmplt_ops; |
| priv = tmplt_priv; |
| |
| nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags); |
| if (!nlh) |
| goto out_nlmsg_trim; |
| tcm = nlmsg_data(nlh); |
| tcm->tcm_family = AF_UNSPEC; |
| tcm->tcm__pad1 = 0; |
| tcm->tcm__pad2 = 0; |
| tcm->tcm_handle = 0; |
| if (block->q) { |
| tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex; |
| tcm->tcm_parent = block->q->handle; |
| } else { |
| tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK; |
| tcm->tcm_block_index = block->index; |
| } |
| |
| if (nla_put_u32(skb, TCA_CHAIN, chain_index)) |
| goto nla_put_failure; |
| |
| if (ops) { |
| if (nla_put_string(skb, TCA_KIND, ops->kind)) |
| goto nla_put_failure; |
| if (ops->tmplt_dump(skb, net, priv) < 0) |
| goto nla_put_failure; |
| } |
| |
| nlh->nlmsg_len = skb_tail_pointer(skb) - b; |
| return skb->len; |
| |
| out_nlmsg_trim: |
| nla_put_failure: |
| nlmsg_trim(skb, b); |
| return -EMSGSIZE; |
| } |
| |
| static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb, |
| u32 seq, u16 flags, int event, bool unicast) |
| { |
| u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; |
| struct tcf_block *block = chain->block; |
| struct net *net = block->net; |
| struct sk_buff *skb; |
| int err = 0; |
| |
| skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
| if (!skb) |
| return -ENOBUFS; |
| |
| if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv, |
| chain->index, net, skb, block, portid, |
| seq, flags, event) <= 0) { |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| |
| if (unicast) |
| err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); |
| else |
| err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, |
| flags & NLM_F_ECHO); |
| |
| if (err > 0) |
| err = 0; |
| return err; |
| } |
| |
| static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops, |
| void *tmplt_priv, u32 chain_index, |
| struct tcf_block *block, struct sk_buff *oskb, |
| u32 seq, u16 flags, bool unicast) |
| { |
| u32 portid = oskb ? NETLINK_CB(oskb).portid : 0; |
| struct net *net = block->net; |
| struct sk_buff *skb; |
| |
| skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); |
| if (!skb) |
| return -ENOBUFS; |
| |
| if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb, |
| block, portid, seq, flags, RTM_DELCHAIN) <= 0) { |
| kfree_skb(skb); |
| return -EINVAL; |
| } |
| |
| if (unicast) |
| return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT); |
| |
| return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO); |
| } |
| |
| static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net, |
| struct nlattr **tca, |
| struct netlink_ext_ack *extack) |
| { |
| const struct tcf_proto_ops *ops; |
| char name[IFNAMSIZ]; |
| void *tmplt_priv; |
| |
| /* If kind is not set, user did not specify template. */ |
| if (!tca[TCA_KIND]) |
| return 0; |
| |
| if (tcf_proto_check_kind(tca[TCA_KIND], name)) { |
| NL_SET_ERR_MSG(extack, "Specified TC chain template name too long"); |
| return -EINVAL; |
| } |
| |
| ops = tcf_proto_lookup_ops(name, true, extack); |
| if (IS_ERR(ops)) |
| return PTR_ERR(ops); |
| if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) { |
| NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier"); |
| return -EOPNOTSUPP; |
| } |
| |
| tmplt_priv = ops->tmplt_create(net, chain, tca, extack); |
| if (IS_ERR(tmplt_priv)) { |
| module_put(ops->owner); |
| return PTR_ERR(tmplt_priv); |
| } |
| chain->tmplt_ops = ops; |
| chain->tmplt_priv = tmplt_priv; |
| return 0; |
| } |
| |
| static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops, |
| void *tmplt_priv) |
| { |
| /* If template ops are set, no work to do for us. */ |
| if (!tmplt_ops) |
| return; |
| |
| tmplt_ops->tmplt_destroy(tmplt_priv); |
| module_put(tmplt_ops->owner); |
| } |
| |
| /* Add/delete/get a chain */ |
| |
| static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n, |
| struct netlink_ext_ack *extack) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct nlattr *tca[TCA_MAX + 1]; |
| struct tcmsg *t; |
| u32 parent; |
| u32 chain_index; |
| struct Qdisc *q = NULL; |
| struct tcf_chain *chain = NULL; |
| struct tcf_block *block; |
| unsigned long cl; |
| int err; |
| |
| if (n->nlmsg_type != RTM_GETCHAIN && |
| !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) |
| return -EPERM; |
| |
| replay: |
| err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX, |
| rtm_tca_policy, extack); |
| if (err < 0) |
| return err; |
| |
| t = nlmsg_data(n); |
| parent = t->tcm_parent; |
| cl = 0; |
| |
| block = tcf_block_find(net, &q, &parent, &cl, |
| t->tcm_ifindex, t->tcm_block_index, extack); |
| if (IS_ERR(block)) |
| return PTR_ERR(block); |
| |
| chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0; |
| if (chain_index > TC_ACT_EXT_VAL_MASK) { |
| NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit"); |
| err = -EINVAL; |
| goto errout_block; |
| } |
| |
| mutex_lock(&block->lock); |
| chain = tcf_chain_lookup(block, chain_index); |
| if (n->nlmsg_type == RTM_NEWCHAIN) { |
| if (chain) { |
| if (tcf_chain_held_by_acts_only(chain)) { |
| /* The chain exists only because there is |
| * some action referencing it. |
| */ |
| tcf_chain_hold(chain); |
| } else { |
| NL_SET_ERR_MSG(extack, "Filter chain already exists"); |
| err = -EEXIST; |
| goto errout_block_locked; |
| } |
| } else { |
| if (!(n->nlmsg_flags & NLM_F_CREATE)) { |
| NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain"); |
| err = -ENOENT; |
| goto errout_block_locked; |
| } |
| chain = tcf_chain_create(block, chain_index); |
| if (!chain) { |
| NL_SET_ERR_MSG(extack, "Failed to create filter chain"); |
| err = -ENOMEM; |
| goto errout_block_locked; |
| } |
| } |
| } else { |
| if (!chain || tcf_chain_held_by_acts_only(chain)) { |
| NL_SET_ERR_MSG(extack, "Cannot find specified filter chain"); |
| err = -EINVAL; |
| goto errout_block_locked; |
| } |
| tcf_chain_hold(chain); |
| } |
| |
| if (n->nlmsg_type == RTM_NEWCHAIN) { |
| /* Modifying chain requires holding parent block lock. In case |
| * the chain was successfully added, take a reference to the |
| * chain. This ensures that an empty chain does not disappear at |
| * the end of this function. |
| */ |
| tcf_chain_hold(chain); |
| chain->explicitly_created = true; |
| } |
| mutex_unlock(&block->lock); |
| |
| switch (n->nlmsg_type) { |
| case RTM_NEWCHAIN: |
| err = tc_chain_tmplt_add(chain, net, tca, extack); |
| if (err) { |
| tcf_chain_put_explicitly_created(chain); |
| goto errout; |
| } |
| |
| tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL, |
| RTM_NEWCHAIN, false); |
| break; |
| case RTM_DELCHAIN: |
| tfilter_notify_chain(net, skb, block, q, parent, n, |
| chain, RTM_DELTFILTER, true); |
| /* Flush the chain first as the user requested chain removal. */ |
| tcf_chain_flush(chain, true); |
| /* In case the chain was successfully deleted, put a reference |
| * to the chain previously taken during addition. |
| */ |
| tcf_chain_put_explicitly_created(chain); |
| break; |
| case RTM_GETCHAIN: |
| err = tc_chain_notify(chain, skb, n->nlmsg_seq, |
| n->nlmsg_seq, n->nlmsg_type, true); |
| if (err < 0) |
| NL_SET_ERR_MSG(extack, "Failed to send chain notify message"); |
| break; |
| default: |
| err = -EOPNOTSUPP; |
| NL_SET_ERR_MSG(extack, "Unsupported message type"); |
| goto errout; |
| } |
| |
| errout: |
| tcf_chain_put(chain); |
| errout_block: |
| tcf_block_release(q, block, true); |
| if (err == -EAGAIN) |
| /* Replay the request. */ |
| goto replay; |
| return err; |
| |
| errout_block_locked: |
| mutex_unlock(&block->lock); |
| goto errout_block; |
| } |
| |
| /* called with RTNL */ |
| static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct nlattr *tca[TCA_MAX + 1]; |
| struct Qdisc *q = NULL; |
| struct tcf_block *block; |
| struct tcmsg *tcm = nlmsg_data(cb->nlh); |
| struct tcf_chain *chain; |
| long index_start; |
| long index; |
| u32 parent; |
| int err; |
| |
| if (nlmsg_len(cb->nlh) < sizeof(*tcm)) |
| return skb->len; |
| |
| err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX, |
| rtm_tca_policy, cb->extack); |
| if (err) |
| return err; |
| |
| if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) { |
| block = tcf_block_refcnt_get(net, tcm->tcm_block_index); |
| if (!block) |
| goto out; |
| /* If we work with block index, q is NULL and parent value |
| * will never be used in the following code. The check |
| * in tcf_fill_node prevents it. However, compiler does not |
| * see that far, so set parent to zero to silence the warning |
| * about parent being uninitialized. |
| */ |
| parent = 0; |
| } else { |
| const struct Qdisc_class_ops *cops; |
| struct net_device *dev; |
| unsigned long cl = 0; |
| |
| dev = __dev_get_by_index(net, tcm->tcm_ifindex); |
| if (!dev) |
| return skb->len; |
| |
| parent = tcm->tcm_parent; |
| if (!parent) { |
| q = dev->qdisc; |
| parent = q->handle; |
| } else { |
| q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent)); |
| } |
| if (!q) |
| goto out; |
| cops = q->ops->cl_ops; |
| if (!cops) |
| goto out; |
| if (!cops->tcf_block) |
| goto out; |
| if (TC_H_MIN(tcm->tcm_parent)) { |
| cl = cops->find(q, tcm->tcm_parent); |
| if (cl == 0) |
| goto out; |
| } |
| block = cops->tcf_block(q, cl, NULL); |
| if (!block) |
| goto out; |
| if (tcf_block_shared(block)) |
| q = NULL; |
| } |
| |
| index_start = cb->args[0]; |
| index = 0; |
| |
| mutex_lock(&block->lock); |
| list_for_each_entry(chain, &block->chain_list, list) { |
| if ((tca[TCA_CHAIN] && |
| nla_get_u32(tca[TCA_CHAIN]) != chain->index)) |
| continue; |
| |