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
  14 struct fib_kuid_range {
  15         kuid_t start;
  16         kuid_t end;
  17 };
  18
  19 struct fib_rule {
  20         struct list_head        list;
  21         int                     iifindex;
  22         int                     oifindex;
  23         u32                     mark;
  24         u32                     mark_mask;
  25         u32                     flags;
  26         u32                     table;
  27         u8                      action;
  28         u8                      l3mdev;
  29         /* 2 bytes hole, try to use */
  30         u32                     target;
  31         __be64                  tun_id;
  32         struct fib_rule __rcu   *ctarget;
  33         struct net              *fr_net;
  34
  35         refcount_t              refcnt;
  36         u32                     pref;
  37         int                     suppress_ifgroup;
  38         int                     suppress_prefixlen;
  39         char                    iifname[IFNAMSIZ];
  40         char                    oifname[IFNAMSIZ];
  41         struct fib_kuid_range   uid_range;
  42         struct rcu_head         rcu;
  43 };
  44
  45 struct fib_lookup_arg {
  46         void                    *lookup_ptr;
  47         void                    *result;
  48         struct fib_rule         *rule;
  49         u32                     table;
  50         int                     flags;
  51 #define FIB_LOOKUP_NOREF                1
  52 #define FIB_LOOKUP_IGNORE_LINKSTATE     2
  53 };
  54
  55 struct fib_rules_ops {
  56         int                     family;
  57         struct list_head        list;
  58         int                     rule_size;
  59         int                     addr_size;
  60         int                     unresolved_rules;
  61         int                     nr_goto_rules;
  62         unsigned int            fib_rules_seq;
  63
  64         int                     (*action)(struct fib_rule *,
  65                                           struct flowi *, int,
  66                                           struct fib_lookup_arg *);
  67         bool                    (*suppress)(struct fib_rule *,
  68                                             struct fib_lookup_arg *);
  69         int                     (*match)(struct fib_rule *,
  70                                          struct flowi *, int);
  71         int                     (*configure)(struct fib_rule *,
  72                                              struct sk_buff *,
  73                                              struct fib_rule_hdr *,
  74                                              struct nlattr **);
  75         int                     (*delete)(struct fib_rule *);
  76         int                     (*compare)(struct fib_rule *,
  77                                            struct fib_rule_hdr *,
  78                                            struct nlattr **);
  79         int                     (*fill)(struct fib_rule *, struct sk_buff *,
  80                                         struct fib_rule_hdr *);
  81         size_t                  (*nlmsg_payload)(struct fib_rule *);
  82
  83         /* Called after modifications to the rules set, must flush
  84          * the route cache if one exists. */
  85         void                    (*flush_cache)(struct fib_rules_ops *ops);
  86
  87         int                     nlgroup;
  88         const struct nla_policy *policy;
  89         struct list_head        rules_list;
  90         struct module           *owner;
  91         struct net              *fro_net;
  92         struct rcu_head         rcu;
  93 };
  94
  95 struct fib_rule_notifier_info {
  96         struct fib_notifier_info info; /* must be first */
  97         struct fib_rule *rule;
  98 };
  99
 100 #define FRA_GENERIC_POLICY \
 101         [FRA_IIFNAME]   = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
 102         [FRA_OIFNAME]   = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
 103         [FRA_PRIORITY]  = { .type = NLA_U32 }, \
 104         [FRA_FWMARK]    = { .type = NLA_U32 }, \
 105         [FRA_FWMASK]    = { .type = NLA_U32 }, \
 106         [FRA_TABLE]     = { .type = NLA_U32 }, \
 107         [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
 108         [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
 109         [FRA_GOTO]      = { .type = NLA_U32 }, \
 110         [FRA_L3MDEV]    = { .type = NLA_U8 }, \
 111         [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) }
 112
 113 static inline void fib_rule_get(struct fib_rule *rule)
 114 {
 115         refcount_inc(&rule->refcnt);
 116 }
 117
 118 static inline void fib_rule_put(struct fib_rule *rule)
 119 {
 120         if (refcount_dec_and_test(&rule->refcnt))
 121                 kfree_rcu(rule, rcu);
 122 }
 123
 124 #ifdef CONFIG_NET_L3_MASTER_DEV
 125 static inline u32 fib_rule_get_table(struct fib_rule *rule,
 126                                      struct fib_lookup_arg *arg)
 127 {
 128         return rule->l3mdev ? arg->table : rule->table;
 129 }
 130 #else
 131 static inline u32 fib_rule_get_table(struct fib_rule *rule,
 132                                      struct fib_lookup_arg *arg)
 133 {
 134         return rule->table;
 135 }
 136 #endif
 137
 138 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
 139 {
 140         if (nla[FRA_TABLE])
 141                 return nla_get_u32(nla[FRA_TABLE]);
 142         return frh->table;
 143 }
 144
 145 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
 146                                          struct net *);
 147 void fib_rules_unregister(struct fib_rules_ops *);
 148
 149 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
 150                      struct fib_lookup_arg *);
 151 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table,
 152                          u32 flags);
 153 bool fib_rule_matchall(const struct fib_rule *rule);
 154 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family);
 155 unsigned int fib_rules_seq_read(struct net *net, int family);
 156
 157 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 158                    struct netlink_ext_ack *extack);
 159 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 160                    struct netlink_ext_ack *extack);
 161 #endif