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         u8                      proto;
  30         u8                      ip_proto;
  31         u32                     target;
  32         __be64                  tun_id;
  33         struct fib_rule __rcu   *ctarget;
  34         struct net              *fr_net;
  35
  36         refcount_t              refcnt;
  37         u32                     pref;
  38         int                     suppress_ifgroup;
  39         int                     suppress_prefixlen;
  40         char                    iifname[IFNAMSIZ];
  41         char                    oifname[IFNAMSIZ];
  42         struct fib_kuid_range   uid_range;
  43         struct fib_rule_port_range      sport_range;
  44         struct fib_rule_port_range      dport_range;
  45         struct rcu_head         rcu;
  46 };
  47
  48 struct fib_lookup_arg {
  49         void                    *lookup_ptr;
  50         void                    *result;
  51         struct fib_rule         *rule;
  52         u32                     table;
  53         int                     flags;
  54 #define FIB_LOOKUP_NOREF                1
  55 #define FIB_LOOKUP_IGNORE_LINKSTATE     2
  56 };
  57
  58 struct fib_rules_ops {
  59         int                     family;
  60         struct list_head        list;
  61         int                     rule_size;
  62         int                     addr_size;
  63         int                     unresolved_rules;
  64         int                     nr_goto_rules;
  65         unsigned int            fib_rules_seq;
  66
  67         int                     (*action)(struct fib_rule *,
  68                                           struct flowi *, int,
  69                                           struct fib_lookup_arg *);
  70         bool                    (*suppress)(struct fib_rule *,
  71                                             struct fib_lookup_arg *);
  72         int                     (*match)(struct fib_rule *,
  73                                          struct flowi *, int);
  74         int                     (*configure)(struct fib_rule *,
  75                                              struct sk_buff *,
  76                                              struct fib_rule_hdr *,
  77                                              struct nlattr **);
  78         int                     (*delete)(struct fib_rule *);
  79         int                     (*compare)(struct fib_rule *,
  80                                            struct fib_rule_hdr *,
  81                                            struct nlattr **);
  82         int                     (*fill)(struct fib_rule *, struct sk_buff *,
  83                                         struct fib_rule_hdr *);
  84         size_t                  (*nlmsg_payload)(struct fib_rule *);
  85
  86         /* Called after modifications to the rules set, must flush
  87          * the route cache if one exists. */
  88         void                    (*flush_cache)(struct fib_rules_ops *ops);
  89
  90         int                     nlgroup;
  91         const struct nla_policy *policy;
  92         struct list_head        rules_list;
  93         struct module           *owner;
  94         struct net              *fro_net;
  95         struct rcu_head         rcu;
  96 };
  97
  98 struct fib_rule_notifier_info {
  99         struct fib_notifier_info info; /* must be first */
 100         struct fib_rule *rule;
 101 };
 102
 103 #define FRA_GENERIC_POLICY \
 104         [FRA_IIFNAME]   = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
 105         [FRA_OIFNAME]   = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
 106         [FRA_PRIORITY]  = { .type = NLA_U32 }, \
 107         [FRA_FWMARK]    = { .type = NLA_U32 }, \
 108         [FRA_FWMASK]    = { .type = NLA_U32 }, \
 109         [FRA_TABLE]     = { .type = NLA_U32 }, \
 110         [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
 111         [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
 112         [FRA_GOTO]      = { .type = NLA_U32 }, \
 113         [FRA_L3MDEV]    = { .type = NLA_U8 }, \
 114         [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) }, \
 115         [FRA_PROTOCOL]  = { .type = NLA_U8 }
 116
 117 static inline void fib_rule_get(struct fib_rule *rule)
 118 {
 119         refcount_inc(&rule->refcnt);
 120 }
 121
 122 static inline void fib_rule_put(struct fib_rule *rule)
 123 {
 124         if (refcount_dec_and_test(&rule->refcnt))
 125                 kfree_rcu(rule, rcu);
 126 }
 127
 128 #ifdef CONFIG_NET_L3_MASTER_DEV
 129 static inline u32 fib_rule_get_table(struct fib_rule *rule,
 130                                      struct fib_lookup_arg *arg)
 131 {
 132         return rule->l3mdev ? arg->table : rule->table;
 133 }
 134 #else
 135 static inline u32 fib_rule_get_table(struct fib_rule *rule,
 136                                      struct fib_lookup_arg *arg)
 137 {
 138         return rule->table;
 139 }
 140 #endif
 141
 142 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
 143 {
 144         if (nla[FRA_TABLE])
 145                 return nla_get_u32(nla[FRA_TABLE]);
 146         return frh->table;
 147 }
 148
 149 static inline bool fib_rule_port_range_set(const struct fib_rule_port_range *range)
 150 {
 151         return range->start != 0 && range->end != 0;
 152 }
 153
 154 static inline bool fib_rule_port_inrange(const struct fib_rule_port_range *a,
 155                                          __be16 port)
 156 {
 157         return ntohs(port) >= a->start &&
 158                 ntohs(port) <= a->end;
 159 }
 160
 161 static inline bool fib_rule_port_range_valid(const struct fib_rule_port_range *a)
 162 {
 163         return a->start != 0 && a->end != 0 && a->end < 0xffff &&
 164                 a->start <= a->end;
 165 }
 166
 167 static inline bool fib_rule_port_range_compare(struct fib_rule_port_range *a,
 168                                                struct fib_rule_port_range *b)
 169 {
 170         return a->start == b->start &&
 171                 a->end == b->end;
 172 }
 173
 174 static inline bool fib_rule_requires_fldissect(struct fib_rule *rule)
 175 {
 176         return rule->ip_proto ||
 177                 fib_rule_port_range_set(&rule->sport_range) ||
 178                 fib_rule_port_range_set(&rule->dport_range);
 179 }
 180
 181 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
 182                                          struct net *);
 183 void fib_rules_unregister(struct fib_rules_ops *);
 184
 185 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
 186                      struct fib_lookup_arg *);
 187 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table,
 188                          u32 flags);
 189 bool fib_rule_matchall(const struct fib_rule *rule);
 190 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family);
 191 unsigned int fib_rules_seq_read(struct net *net, int family);
 192
 193 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 194                    struct netlink_ext_ack *extack);
 195 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 196                    struct netlink_ext_ack *extack);
 197 #endif