include/net/fib_rules.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __NET_FIB_RULES_H
   3 #define __NET_FIB_RULES_H
   4
   5 #include <linux/types.h>
   6 #include <linux/slab.h>
   7 #include <linux/netdevice.h>
   8 #include <linux/fib_rules.h>
   9 #include <linux/refcount.h>
  10 #include <net/flow.h>
  11 #include <net/rtnetlink.h>
  12 #include <net/fib_notifier.h>
  13 #include <linux/indirect_call_wrapper.h>
  14
  15 struct fib_kuid_range {
  16         kuid_t start;
  17         kuid_t end;
  18 };
  19
  20 struct fib_rule {
  21         struct list_head        list;
  22         int                     iifindex;
  23         int                     oifindex;
  24         u32                     mark;
  25         u32                     mark_mask;
  26         u32                     flags;
  27         u32                     table;
  28         u8                      action;
  29         u8                      l3mdev;
  30         u8                      proto;
  31         u8                      ip_proto;
  32         u32                     target;
  33         __be64                  tun_id;
  34         struct fib_rule __rcu   *ctarget;
  35         struct net              *fr_net;
  36
  37         refcount_t              refcnt;
  38         u32                     pref;
  39         int                     suppress_ifgroup;
  40         int                     suppress_prefixlen;
  41         char                    iifname[IFNAMSIZ];
  42         char                    oifname[IFNAMSIZ];
  43         struct fib_kuid_range   uid_range;
  44         struct fib_rule_port_range      sport_range;
  45         struct fib_rule_port_range      dport_range;
  46         struct rcu_head         rcu;
  47 };
  48
  49 struct fib_lookup_arg {
  50         void                    *lookup_ptr;
  51         const void              *lookup_data;
  52         void                    *result;
  53         struct fib_rule         *rule;
  54         u32                     table;
  55         int                     flags;
  56 #define FIB_LOOKUP_NOREF                1
  57 #define FIB_LOOKUP_IGNORE_LINKSTATE     2
  58 };
  59
  60 struct fib_rules_ops {
  61         int                     family;
  62         struct list_head        list;
  63         int                     rule_size;
  64         int                     addr_size;
  65         int                     unresolved_rules;
  66         int                     nr_goto_rules;
  67         unsigned int            fib_rules_seq;
  68
  69         int                     (*action)(struct fib_rule *,
  70                                           struct flowi *, int,
  71                                           struct fib_lookup_arg *);
  72         bool                    (*suppress)(struct fib_rule *, int,
  73                                             struct fib_lookup_arg *);
  74         int                     (*match)(struct fib_rule *,
  75                                          struct flowi *, int);
  76         int                     (*configure)(struct fib_rule *,
  77                                              struct sk_buff *,
  78                                              struct fib_rule_hdr *,
  79                                              struct nlattr **,
  80                                              struct netlink_ext_ack *);
  81         int                     (*delete)(struct fib_rule *);
  82         int                     (*compare)(struct fib_rule *,
  83                                            struct fib_rule_hdr *,
  84                                            struct nlattr **);
  85         int                     (*fill)(struct fib_rule *, struct sk_buff *,
  86                                         struct fib_rule_hdr *);
  87         size_t                  (*nlmsg_payload)(struct fib_rule *);
  88
  89         /* Called after modifications to the rules set, must flush
  90          * the route cache if one exists. */
  91         void                    (*flush_cache)(struct fib_rules_ops *ops);
  92
  93         int                     nlgroup;
  94         struct list_head        rules_list;
  95         struct module           *owner;
  96         struct net              *fro_net;
  97         struct rcu_head         rcu;
  98 };
  99
 100 struct fib_rule_notifier_info {
 101         struct fib_notifier_info info; /* must be first */
 102         struct fib_rule *rule;
 103 };
 104
 105 static inline void fib_rule_get(struct fib_rule *rule)
 106 {
 107         refcount_inc(&rule->refcnt);
 108 }
 109
 110 static inline void fib_rule_put(struct fib_rule *rule)
 111 {
 112         if (refcount_dec_and_test(&rule->refcnt))
 113                 kfree_rcu(rule, rcu);
 114 }
 115
 116 #ifdef CONFIG_NET_L3_MASTER_DEV
 117 static inline u32 fib_rule_get_table(struct fib_rule *rule,
 118                                      struct fib_lookup_arg *arg)
 119 {
 120         return rule->l3mdev ? arg->table : rule->table;
 121 }
 122 #else
 123 static inline u32 fib_rule_get_table(struct fib_rule *rule,
 124                                      struct fib_lookup_arg *arg)
 125 {
 126         return rule->table;
 127 }
 128 #endif
 129
 130 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
 131 {
 132         if (nla[FRA_TABLE])
 133                 return nla_get_u32(nla[FRA_TABLE]);
 134         return frh->table;
 135 }
 136
 137 static inline bool fib_rule_port_range_set(const struct fib_rule_port_range *range)
 138 {
 139         return range->start != 0 && range->end != 0;
 140 }
 141
 142 static inline bool fib_rule_port_inrange(const struct fib_rule_port_range *a,
 143                                          __be16 port)
 144 {
 145         return ntohs(port) >= a->start &&
 146                 ntohs(port) <= a->end;
 147 }
 148
 149 static inline bool fib_rule_port_range_valid(const struct fib_rule_port_range *a)
 150 {
 151         return a->start != 0 && a->end != 0 && a->end < 0xffff &&
 152                 a->start <= a->end;
 153 }
 154
 155 static inline bool fib_rule_port_range_compare(struct fib_rule_port_range *a,
 156                                                struct fib_rule_port_range *b)
 157 {
 158         return a->start == b->start &&
 159                 a->end == b->end;
 160 }
 161
 162 static inline bool fib_rule_requires_fldissect(struct fib_rule *rule)
 163 {
 164         return rule->iifindex != LOOPBACK_IFINDEX && (rule->ip_proto ||
 165                 fib_rule_port_range_set(&rule->sport_range) ||
 166                 fib_rule_port_range_set(&rule->dport_range));
 167 }
 168
 169 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
 170                                          struct net *);
 171 void fib_rules_unregister(struct fib_rules_ops *);
 172
 173 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
 174                      struct fib_lookup_arg *);
 175 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table);
 176 bool fib_rule_matchall(const struct fib_rule *rule);
 177 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
 178                    struct netlink_ext_ack *extack);
 179 unsigned int fib_rules_seq_read(const struct net *net, int family);
 180
 181 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 182                    struct netlink_ext_ack *extack);
 183 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 184                    struct netlink_ext_ack *extack);
 185
 186 INDIRECT_CALLABLE_DECLARE(int fib6_rule_match(struct fib_rule *rule,
 187                                             struct flowi *fl, int flags));
 188 INDIRECT_CALLABLE_DECLARE(int fib4_rule_match(struct fib_rule *rule,
 189                                             struct flowi *fl, int flags));
 190
 191 INDIRECT_CALLABLE_DECLARE(int fib6_rule_action(struct fib_rule *rule,
 192                             struct flowi *flp, int flags,
 193                             struct fib_lookup_arg *arg));
 194 INDIRECT_CALLABLE_DECLARE(int fib4_rule_action(struct fib_rule *rule,
 195                             struct flowi *flp, int flags,
 196                             struct fib_lookup_arg *arg));
 197
 198 INDIRECT_CALLABLE_DECLARE(bool fib6_rule_suppress(struct fib_rule *rule,
 199                                                 int flags,
 200                                                 struct fib_lookup_arg *arg));
 201 INDIRECT_CALLABLE_DECLARE(bool fib4_rule_suppress(struct fib_rule *rule,
 202                                                 int flags,
 203                                                 struct fib_lookup_arg *arg));
 204 #endif