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         const void              *lookup_data;
  51         void                    *result;
  52         struct fib_rule         *rule;
  53         u32                     table;
  54         int                     flags;
  55 #define FIB_LOOKUP_NOREF                1
  56 #define FIB_LOOKUP_IGNORE_LINKSTATE     2
  57 };
  58
  59 struct fib_rules_ops {
  60         int                     family;
  61         struct list_head        list;
  62         int                     rule_size;
  63         int                     addr_size;
  64         int                     unresolved_rules;
  65         int                     nr_goto_rules;
  66         unsigned int            fib_rules_seq;
  67
  68         int                     (*action)(struct fib_rule *,
  69                                           struct flowi *, int,
  70                                           struct fib_lookup_arg *);
  71         bool                    (*suppress)(struct fib_rule *,
  72                                             struct fib_lookup_arg *);
  73         int                     (*match)(struct fib_rule *,
  74                                          struct flowi *, int);
  75         int                     (*configure)(struct fib_rule *,
  76                                              struct sk_buff *,
  77                                              struct fib_rule_hdr *,
  78                                              struct nlattr **,
  79                                              struct netlink_ext_ack *);
  80         int                     (*delete)(struct fib_rule *);
  81         int                     (*compare)(struct fib_rule *,
  82                                            struct fib_rule_hdr *,
  83                                            struct nlattr **);
  84         int                     (*fill)(struct fib_rule *, struct sk_buff *,
  85                                         struct fib_rule_hdr *);
  86         size_t                  (*nlmsg_payload)(struct fib_rule *);
  87
  88         /* Called after modifications to the rules set, must flush
  89          * the route cache if one exists. */
  90         void                    (*flush_cache)(struct fib_rules_ops *ops);
  91
  92         int                     nlgroup;
  93         const struct nla_policy *policy;
  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 #define FRA_GENERIC_POLICY \
 106         [FRA_UNSPEC]    = { .strict_start_type = FRA_DPORT_RANGE + 1 }, \
 107         [FRA_IIFNAME]   = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
 108         [FRA_OIFNAME]   = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
 109         [FRA_PRIORITY]  = { .type = NLA_U32 }, \
 110         [FRA_FWMARK]    = { .type = NLA_U32 }, \
 111         [FRA_FWMASK]    = { .type = NLA_U32 }, \
 112         [FRA_TABLE]     = { .type = NLA_U32 }, \
 113         [FRA_SUPPRESS_PREFIXLEN] = { .type = NLA_U32 }, \
 114         [FRA_SUPPRESS_IFGROUP] = { .type = NLA_U32 }, \
 115         [FRA_GOTO]      = { .type = NLA_U32 }, \
 116         [FRA_L3MDEV]    = { .type = NLA_U8 }, \
 117         [FRA_UID_RANGE] = { .len = sizeof(struct fib_rule_uid_range) }, \
 118         [FRA_PROTOCOL]  = { .type = NLA_U8 }, \
 119         [FRA_IP_PROTO]  = { .type = NLA_U8 }, \
 120         [FRA_SPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) }, \
 121         [FRA_DPORT_RANGE] = { .len = sizeof(struct fib_rule_port_range) }
 122
 123
 124 static inline void fib_rule_get(struct fib_rule *rule)
 125 {
 126         refcount_inc(&rule->refcnt);
 127 }
 128
 129 static inline void fib_rule_put(struct fib_rule *rule)
 130 {
 131         if (refcount_dec_and_test(&rule->refcnt))
 132                 kfree_rcu(rule, rcu);
 133 }
 134
 135 #ifdef CONFIG_NET_L3_MASTER_DEV
 136 static inline u32 fib_rule_get_table(struct fib_rule *rule,
 137                                      struct fib_lookup_arg *arg)
 138 {
 139         return rule->l3mdev ? arg->table : rule->table;
 140 }
 141 #else
 142 static inline u32 fib_rule_get_table(struct fib_rule *rule,
 143                                      struct fib_lookup_arg *arg)
 144 {
 145         return rule->table;
 146 }
 147 #endif
 148
 149 static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
 150 {
 151         if (nla[FRA_TABLE])
 152                 return nla_get_u32(nla[FRA_TABLE]);
 153         return frh->table;
 154 }
 155
 156 static inline bool fib_rule_port_range_set(const struct fib_rule_port_range *range)
 157 {
 158         return range->start != 0 && range->end != 0;
 159 }
 160
 161 static inline bool fib_rule_port_inrange(const struct fib_rule_port_range *a,
 162                                          __be16 port)
 163 {
 164         return ntohs(port) >= a->start &&
 165                 ntohs(port) <= a->end;
 166 }
 167
 168 static inline bool fib_rule_port_range_valid(const struct fib_rule_port_range *a)
 169 {
 170         return a->start != 0 && a->end != 0 && a->end < 0xffff &&
 171                 a->start <= a->end;
 172 }
 173
 174 static inline bool fib_rule_port_range_compare(struct fib_rule_port_range *a,
 175                                                struct fib_rule_port_range *b)
 176 {
 177         return a->start == b->start &&
 178                 a->end == b->end;
 179 }
 180
 181 static inline bool fib_rule_requires_fldissect(struct fib_rule *rule)
 182 {
 183         return rule->iifindex != LOOPBACK_IFINDEX && (rule->ip_proto ||
 184                 fib_rule_port_range_set(&rule->sport_range) ||
 185                 fib_rule_port_range_set(&rule->dport_range));
 186 }
 187
 188 struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *,
 189                                          struct net *);
 190 void fib_rules_unregister(struct fib_rules_ops *);
 191
 192 int fib_rules_lookup(struct fib_rules_ops *, struct flowi *, int flags,
 193                      struct fib_lookup_arg *);
 194 int fib_default_rule_add(struct fib_rules_ops *, u32 pref, u32 table,
 195                          u32 flags);
 196 bool fib_rule_matchall(const struct fib_rule *rule);
 197 int fib_rules_dump(struct net *net, struct notifier_block *nb, int family,
 198                    struct netlink_ext_ack *extack);
 199 unsigned int fib_rules_seq_read(struct net *net, int family);
 200
 201 int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 202                    struct netlink_ext_ack *extack);
 203 int fib_nl_delrule(struct sk_buff *skb, struct nlmsghdr *nlh,
 204                    struct netlink_ext_ack *extack);
 205 #endif