proto/radv/radv.h

   1 /*
   2  *      BIRD -- Router Advertisement
   3  *
   4  *      (c) 2011--2019 Ondrej Zajicek <santiago@crfreenet.org>
   5  *      (c) 2011--2019 CZ.NIC z.s.p.o.
   6  *
   7  *      Can be freely distributed and used under the terms of the GNU GPL.
   8  */
   9
  10 #ifndef _BIRD_RADV_H_
  11 #define _BIRD_RADV_H_
  12
  13 #include "nest/bird.h"
  14
  15 #include "lib/ip.h"
  16 #include "lib/lists.h"
  17 #include "lib/socket.h"
  18 #include "lib/timer.h"
  19 #include "lib/resource.h"
  20 #include "nest/protocol.h"
  21 #include "nest/iface.h"
  22 #include "nest/route.h"
  23 #include "nest/cli.h"
  24 #include "nest/locks.h"
  25 #include "conf/conf.h"
  26 #include "lib/string.h"
  27
  28
  29 #define ICMPV6_PROTO 58
  30
  31 #define ICMPV6_RS 133
  32 #define ICMPV6_RA 134
  33
  34 #define MAX_INITIAL_RTR_ADVERTISEMENTS 3
  35 #define MAX_INITIAL_RTR_ADVERT_INTERVAL (16 S_)
  36
  37 #define DEFAULT_MAX_RA_INT 600
  38 #define DEFAULT_MIN_DELAY 3
  39 #define DEFAULT_CURRENT_HOP_LIMIT 64
  40
  41 #define DEFAULT_VALID_LIFETIME 86400
  42 #define DEFAULT_PREFERRED_LIFETIME 14400
  43
  44 #define DEFAULT_DNS_LIFETIME_MULT 3
  45
  46
  47 struct radv_config
  48 {
  49   struct proto_config c;
  50   list patt_list;               /* List of iface configs (struct radv_iface_config) */
  51   list pref_list;               /* Global list of prefix configs (struct radv_prefix_config) */
  52   list rdnss_list;              /* Global list of RDNSS configs (struct radv_rdnss_config) */
  53   list dnssl_list;              /* Global list of DNSSL configs (struct radv_dnssl_config) */
  54
  55   net_addr trigger;             /* Prefix of a trigger route, if defined */
  56   u8 propagate_routes;          /* Do we propagate more specific routes (RFC 4191)? */
  57   u32 max_linger_time;          /* Maximum of interface route_linger_time */
  58 };
  59
  60 struct radv_iface_config
  61 {
  62   struct iface_patt i;
  63   list pref_list;               /* Local list of prefix configs (struct radv_prefix_config) */
  64   list rdnss_list;              /* Local list of RDNSS configs (struct radv_rdnss_config) */
  65   list dnssl_list;              /* Local list of DNSSL configs (struct radv_dnssl_config) */
  66
  67   u32 min_ra_int;               /* Standard options from RFC 4861 */
  68   u32 max_ra_int;
  69   u32 min_delay;
  70
  71   u8 solicited_ra_unicast;      /* Send solicited RAs as unicast */
  72
  73   u32 prefix_linger_time;       /* How long we advertise dead prefixes with lifetime 0 */
  74   u32 route_linger_time;        /* How long we advertise dead routes with lifetime 0 */
  75
  76   u8 rdnss_local;               /* Global list is not used for RDNSS */
  77   u8 dnssl_local;               /* Global list is not used for DNSSL */
  78
  79   u8 managed;                   /* Standard options from RFC 4861 */
  80   u8 other_config;
  81   u32 link_mtu;
  82   u32 reachable_time;
  83   u32 retrans_timer;
  84   u32 current_hop_limit;
  85   u32 default_lifetime;
  86   u32 route_lifetime;           /* Lifetime for the RFC 4191 routes */
  87   u8 default_lifetime_sensitive; /* Whether default_lifetime depends on trigger */
  88   u8 route_lifetime_sensitive;  /* Whether route_lifetime depends on trigger */
  89   u8 default_preference;        /* Default Router Preference (RFC 4191) */
  90   u8 route_preference;          /* Specific Route Preference (RFC 4191) */
  91 };
  92
  93 struct radv_prefix_config
  94 {
  95   node n;
  96   net_addr_ip6 prefix;
  97
  98   u8 skip;                      /* Do not include this prefix to RA */
  99   u8 onlink;                    /* Standard options from RFC 4861 */
 100   u8 autonomous;
 101   u32 valid_lifetime;
 102   u32 preferred_lifetime;
 103   u8 valid_lifetime_sensitive;   /* Whether valid_lifetime depends on trigger */
 104   u8 preferred_lifetime_sensitive; /* Whether preferred_lifetime depends on trigger */
 105 };
 106
 107 struct radv_rdnss_config
 108 {
 109   node n;
 110   u32 lifetime;                 /* Valid if lifetime_mult is 0 */
 111   u16 lifetime_mult;            /* Lifetime specified as multiple of max_ra_int */
 112   ip6_addr server;              /* IP address of recursive DNS server */
 113 };
 114
 115 struct radv_dnssl_config
 116 {
 117   node n;
 118   u32 lifetime;                 /* Valid if lifetime_mult is 0 */
 119   u16 lifetime_mult;            /* Lifetime specified as multiple of max_ra_int */
 120   u8 dlen_first;                /* Length of first label in domain */
 121   u8 dlen_all;                  /* Both dlen_ filled in radv_process_domain() */
 122   char *domain;                 /* Domain for DNS search list, in processed form */
 123 };
 124
 125 /*
 126  * One more specific route as per RFC 4191.
 127  *
 128  * Note that it does *not* contain the next hop field. The next hop is always
 129  * the router sending the advertisment and the more specific route only allows
 130  * overriding the preference of the route.
 131  */
 132 struct radv_route
 133 {
 134   u32 lifetime;                 /* Lifetime from an attribute */
 135   u8 lifetime_set;              /* Whether lifetime is defined */
 136   u8 preference;                /* Preference of the route, RA_PREF_* */
 137   u8 preference_set;            /* Whether preference is defined */
 138   u8 valid;                     /* Whethe route is valid or withdrawn */
 139   btime changed;                /* Last time when the route changed */
 140
 141   struct fib_node n;
 142 };
 143
 144 struct radv_proto
 145 {
 146   struct proto p;
 147   list iface_list;              /* List of active ifaces */
 148   u8 valid;                     /* Router is valid for forwarding, used for shutdown */
 149   u8 active;                    /* Whether radv is active w.r.t. triggers */
 150   u8 fib_up;                    /* FIB table (routes) is initialized */
 151   struct fib routes;            /* FIB table of specific routes (struct radv_route) */
 152   btime prune_time;             /* Next time of route table pruning */
 153 };
 154
 155 struct radv_prefix              /* One prefix we advertise */
 156 {
 157   node n;
 158   net_addr_ip6 prefix;
 159
 160   u8 valid;                     /* Is the prefix valid? If not, we advertise it
 161                                    with 0 lifetime, so clients stop using it */
 162   u8 mark;                      /* A temporary mark for processing */
 163   btime changed;                /* Last time when the prefix changed */
 164   struct radv_prefix_config *cf; /* The config tied to this prefix */
 165 };
 166
 167 struct radv_iface
 168 {
 169   node n;
 170   struct radv_proto *ra;
 171   struct radv_iface_config *cf; /* Related config, must be updated in reconfigure */
 172   struct iface *iface;
 173   struct ifa *addr;             /* Link-local address of iface */
 174   struct pool *pool;            /* A pool for interface-specific things */
 175   list prefixes;                /* The prefixes we advertise (struct radv_prefix) */
 176   btime prune_time;             /* Next time of prefix list pruning */
 177   btime valid_time;             /* Cached packet is valid until first linger timeout */
 178
 179   timer *timer;
 180   struct object_lock *lock;
 181   sock *sk;
 182
 183   btime last;                   /* Time of last sending of RA */
 184   u16 plen;                     /* Length of prepared RA in tbuf, or 0 if not valid */
 185   byte initial;                 /* How many RAs are still to be sent as initial */
 186 };
 187
 188 #define RA_EV_INIT 1            /* Switch to initial mode */
 189 #define RA_EV_CHANGE 2          /* Change of options or prefixes */
 190 #define RA_EV_RS 3              /* Received RS */
 191
 192 /* Default Router Preferences (RFC 4191) */
 193 #define RA_PREF_LOW     0x18
 194 #define RA_PREF_MEDIUM  0x00
 195 #define RA_PREF_HIGH    0x08
 196 #define RA_PREF_MASK    0x18
 197
 198 /* Attributes */
 199 #define EA_RA_PREFERENCE        EA_CODE(PROTOCOL_RADV, 0)
 200 #define EA_RA_LIFETIME          EA_CODE(PROTOCOL_RADV, 1)
 201
 202 #ifdef LOCAL_DEBUG
 203 #define RADV_FORCE_DEBUG 1
 204 #else
 205 #define RADV_FORCE_DEBUG 0
 206 #endif
 207 #define RADV_TRACE(flags, msg, args...) do { if ((p->p.debug & flags) || RADV_FORCE_DEBUG) \
 208         log(L_TRACE "%s: " msg, p->p.name , ## args ); } while(0)
 209
 210
 211 /* Invalidate cached RA packet */
 212 static inline void radv_invalidate(struct radv_iface *ifa)
 213 { ifa->plen = 0; }
 214
 215 /* radv.c */
 216 void radv_iface_notify(struct radv_iface *ifa, int event);
 217
 218 /* packets.c */
 219 int radv_process_domain(struct radv_dnssl_config *cf);
 220 void radv_send_ra(struct radv_iface *ifa, ip_addr to);
 221 int radv_sk_open(struct radv_iface *ifa);
 222
 223
 224
 225 #endif /* _BIRD_RADV_H_ */