// SPDX-License-Identifier: GPL-2.0-or-later /* * net/sched/em_meta.c Metadata ematch * * Authors: Thomas Graf <[email protected]> * * ========================================================================== * * The metadata ematch compares two meta objects where each object * represents either a meta value stored in the kernel or a static * value provided by userspace. The objects are not provided by * userspace itself but rather a definition providing the information * to build them. Every object is of a certain type which must be * equal to the object it is being compared to. * * The definition of a objects conists of the type (meta type), a * identifier (meta id) and additional type specific information. * The meta id is either TCF_META_TYPE_VALUE for values provided by * userspace or a index to the meta operations table consisting of * function pointers to type specific meta data collectors returning * the value of the requested meta value. * * lvalue rvalue * +-----------+ +-----------+ * | type: INT | | type: INT | * def | id: DEV | | id: VALUE | * | data: | | data: 3 | * +-----------+ +-----------+ * | | * ---> meta_ops[INT][DEV](...) | * | | * ----------- | * V V * +-----------+ +-----------+ * | type: INT | | type: INT | * obj | id: DEV | | id: VALUE | * | data: 2 |<--data got filled out | data: 3 | * +-----------+ +-----------+ * | | * --------------> 2 equals 3 <-------------- * * This is a simplified schema, the complexity varies depending * on the meta type. Obviously, the length of the data must also * be provided for non-numeric types. * * Additionally, type dependent modifiers such as shift operators * or mask may be applied to extend the functionality. As of now, * the variable length type supports shifting the byte string to * the right, eating up any number of octets and thus supporting * wildcard interface name comparisons such as "ppp%" matching * ppp0..9. * * NOTE: Certain meta values depend on other subsystems and are * only available if that subsystem is enabled in the kernel. */ #include <linux/slab.h> #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/sched/loadavg.h> #include <linux/string.h> #include <linux/skbuff.h> #include <linux/random.h> #include <linux/if_vlan.h> #include <linux/tc_ematch/tc_em_meta.h> #include <net/dst.h> #include <net/route.h> #include <net/pkt_cls.h> #include <net/sock.h> struct meta_obj { … }; struct meta_value { … }; struct meta_match { … }; static inline int meta_id(struct meta_value *v) { … } static inline int meta_type(struct meta_value *v) { … } #define META_COLLECTOR(FUNC) … /************************************************************************** * System status & misc **************************************************************************/ META_COLLECTOR(int_random) { … } static inline unsigned long fixed_loadavg(int load) { … } META_COLLECTOR(int_loadavg_0) { … } META_COLLECTOR(int_loadavg_1) { … } META_COLLECTOR(int_loadavg_2) { … } /************************************************************************** * Device names & indices **************************************************************************/ static inline int int_dev(struct net_device *dev, struct meta_obj *dst) { … } static inline int var_dev(struct net_device *dev, struct meta_obj *dst) { … } META_COLLECTOR(int_dev) { … } META_COLLECTOR(var_dev) { … } /************************************************************************** * vlan tag **************************************************************************/ META_COLLECTOR(int_vlan_tag) { … } /************************************************************************** * skb attributes **************************************************************************/ META_COLLECTOR(int_priority) { … } META_COLLECTOR(int_protocol) { … } META_COLLECTOR(int_pkttype) { … } META_COLLECTOR(int_pktlen) { … } META_COLLECTOR(int_datalen) { … } META_COLLECTOR(int_maclen) { … } META_COLLECTOR(int_rxhash) { … } /************************************************************************** * Netfilter **************************************************************************/ META_COLLECTOR(int_mark) { … } /************************************************************************** * Traffic Control **************************************************************************/ META_COLLECTOR(int_tcindex) { … } /************************************************************************** * Routing **************************************************************************/ META_COLLECTOR(int_rtclassid) { … } META_COLLECTOR(int_rtiif) { … } /************************************************************************** * Socket Attributes **************************************************************************/ #define skip_nonlocal(skb) … META_COLLECTOR(int_sk_family) { … } META_COLLECTOR(int_sk_state) { … } META_COLLECTOR(int_sk_reuse) { … } META_COLLECTOR(int_sk_bound_if) { … } META_COLLECTOR(var_sk_bound_if) { … } META_COLLECTOR(int_sk_refcnt) { … } META_COLLECTOR(int_sk_rcvbuf) { … } META_COLLECTOR(int_sk_shutdown) { … } META_COLLECTOR(int_sk_proto) { … } META_COLLECTOR(int_sk_type) { … } META_COLLECTOR(int_sk_rmem_alloc) { … } META_COLLECTOR(int_sk_wmem_alloc) { … } META_COLLECTOR(int_sk_omem_alloc) { … } META_COLLECTOR(int_sk_rcv_qlen) { … } META_COLLECTOR(int_sk_snd_qlen) { … } META_COLLECTOR(int_sk_wmem_queued) { … } META_COLLECTOR(int_sk_fwd_alloc) { … } META_COLLECTOR(int_sk_sndbuf) { … } META_COLLECTOR(int_sk_alloc) { … } META_COLLECTOR(int_sk_hash) { … } META_COLLECTOR(int_sk_lingertime) { … } META_COLLECTOR(int_sk_err_qlen) { … } META_COLLECTOR(int_sk_ack_bl) { … } META_COLLECTOR(int_sk_max_ack_bl) { … } META_COLLECTOR(int_sk_prio) { … } META_COLLECTOR(int_sk_rcvlowat) { … } META_COLLECTOR(int_sk_rcvtimeo) { … } META_COLLECTOR(int_sk_sndtimeo) { … } META_COLLECTOR(int_sk_sendmsg_off) { … } META_COLLECTOR(int_sk_write_pend) { … } /************************************************************************** * Meta value collectors assignment table **************************************************************************/ struct meta_ops { … }; #define META_ID(name) … #define META_FUNC(name) … /* Meta value operations table listing all meta value collectors and * assigns them to a type and meta id. */ static struct meta_ops __meta_ops[TCF_META_TYPE_MAX + 1][TCF_META_ID_MAX + 1] = …; static inline struct meta_ops *meta_ops(struct meta_value *val) { … } /************************************************************************** * Type specific operations for TCF_META_TYPE_VAR **************************************************************************/ static int meta_var_compare(struct meta_obj *a, struct meta_obj *b) { … } static int meta_var_change(struct meta_value *dst, struct nlattr *nla) { … } static void meta_var_destroy(struct meta_value *v) { … } static void meta_var_apply_extras(struct meta_value *v, struct meta_obj *dst) { … } static int meta_var_dump(struct sk_buff *skb, struct meta_value *v, int tlv) { … } /************************************************************************** * Type specific operations for TCF_META_TYPE_INT **************************************************************************/ static int meta_int_compare(struct meta_obj *a, struct meta_obj *b) { … } static int meta_int_change(struct meta_value *dst, struct nlattr *nla) { … } static void meta_int_apply_extras(struct meta_value *v, struct meta_obj *dst) { … } static int meta_int_dump(struct sk_buff *skb, struct meta_value *v, int tlv) { … } /************************************************************************** * Type specific operations table **************************************************************************/ struct meta_type_ops { … }; static const struct meta_type_ops __meta_type_ops[TCF_META_TYPE_MAX + 1] = …; static inline const struct meta_type_ops *meta_type_ops(struct meta_value *v) { … } /************************************************************************** * Core **************************************************************************/ static int meta_get(struct sk_buff *skb, struct tcf_pkt_info *info, struct meta_value *v, struct meta_obj *dst) { … } static int em_meta_match(struct sk_buff *skb, struct tcf_ematch *m, struct tcf_pkt_info *info) { … } static void meta_delete(struct meta_match *meta) { … } static inline int meta_change_data(struct meta_value *dst, struct nlattr *nla) { … } static inline int meta_is_supported(struct meta_value *val) { … } static const struct nla_policy meta_policy[TCA_EM_META_MAX + 1] = …; static int em_meta_change(struct net *net, void *data, int len, struct tcf_ematch *m) { … } static void em_meta_destroy(struct tcf_ematch *m) { … } static int em_meta_dump(struct sk_buff *skb, struct tcf_ematch *em) { … } static struct tcf_ematch_ops em_meta_ops = …; static int __init init_em_meta(void) { … } static void __exit exit_em_meta(void) { … } MODULE_DESCRIPTION(…) …; MODULE_LICENSE(…) …; module_init(…) …; module_exit(exit_em_meta); MODULE_ALIAS_TCF_EMATCH(…);
Codebase Browser
linux