src/odhcp6c.h

   1 /**
   2  * Copyright (C) 2012-2014 Steven Barth <steven@midlink.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License v2 as published by
   6  * the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14 #pragma once
  15 #include <stdint.h>
  16 #include <stdbool.h>
  17 #include <netinet/in.h>
  18
  19 #define _unused __attribute__((unused))
  20 #define _packed __attribute__((packed))
  21
  22 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
  23
  24 #define ND_OPT_RECURSIVE_DNS 25
  25 #define ND_OPT_DNSSL 31
  26
  27 #define DHCPV6_SOL_MAX_RT 3600
  28 #define DHCPV6_REQ_MAX_RT 30
  29 #define DHCPV6_CNF_MAX_RT 4
  30 #define DHCPV6_REN_MAX_RT 600
  31 #define DHCPV6_REB_MAX_RT 600
  32 #define DHCPV6_INF_MAX_RT 3600
  33
  34 #define DEFAULT_MIN_UPDATE_INTERVAL 30
  35
  36 enum dhcvp6_opt {
  37         DHCPV6_OPT_CLIENTID = 1,
  38         DHCPV6_OPT_SERVERID = 2,
  39         DHCPV6_OPT_IA_NA = 3,
  40         DHCPV6_OPT_IA_ADDR = 5,
  41         DHCPV6_OPT_ORO = 6,
  42         DHCPV6_OPT_PREF = 7,
  43         DHCPV6_OPT_ELAPSED = 8,
  44         DHCPV6_OPT_RELAY_MSG = 9,
  45         DHCPV6_OPT_AUTH = 11,
  46         DHCPV6_OPT_STATUS = 13,
  47         DHCPV6_OPT_RAPID_COMMIT = 14,
  48         DHCPV6_OPT_USER_CLASS = 15,
  49         DHCPV6_OPT_VENDOR_CLASS = 16,
  50         DHCPV6_OPT_RECONF_MESSAGE = 19,
  51         DHCPV6_OPT_RECONF_ACCEPT = 20,
  52         DHCPV6_OPT_DNS_SERVERS = 23,
  53         DHCPV6_OPT_DNS_DOMAIN = 24,
  54         DHCPV6_OPT_IA_PD = 25,
  55         DHCPV6_OPT_IA_PREFIX = 26,
  56         DHCPV6_OPT_SNTP_SERVERS = 31,
  57         DHCPV6_OPT_INFO_REFRESH = 32,
  58         DHCPV6_OPT_FQDN = 39,
  59         DHCPV6_OPT_NTP_SERVER = 56,
  60         DHCPV6_OPT_SIP_SERVER_D = 21,
  61         DHCPV6_OPT_SIP_SERVER_A = 22,
  62         DHCPV6_OPT_AFTR_NAME = 64,
  63         DHCPV6_OPT_PD_EXCLUDE = 67,
  64         DHCPV6_OPT_SOL_MAX_RT = 82,
  65         DHCPV6_OPT_INF_MAX_RT = 83,
  66 #ifdef EXT_PREFIX_CLASS
  67         /* draft-bhandari-dhc-class-based-prefix, not yet standardized */
  68         DHCPV6_OPT_PREFIX_CLASS = EXT_PREFIX_CLASS,
  69 #endif
  70 };
  71
  72 enum dhcpv6_opt_npt {
  73         NTP_SRV_ADDR = 1,
  74         NTP_MC_ADDR = 2,
  75         NTP_SRV_FQDN = 3
  76 };
  77
  78 enum dhcpv6_msg {
  79         DHCPV6_MSG_UNKNOWN = 0,
  80         DHCPV6_MSG_SOLICIT = 1,
  81         DHCPV6_MSG_ADVERT = 2,
  82         DHCPV6_MSG_REQUEST = 3,
  83         DHCPV6_MSG_RENEW = 5,
  84         DHCPV6_MSG_REBIND = 6,
  85         DHCPV6_MSG_REPLY = 7,
  86         DHCPV6_MSG_RELEASE = 8,
  87         DHCPV6_MSG_DECLINE = 9,
  88         DHCPV6_MSG_RECONF = 10,
  89         DHCPV6_MSG_INFO_REQ = 11,
  90         _DHCPV6_MSG_MAX
  91 };
  92
  93 enum dhcpv6_status {
  94         DHCPV6_Success = 0,
  95         DHCPV6_UnspecFail = 1,
  96         DHCPV6_NoAddrsAvail = 2,
  97         DHCPV6_NoBinding = 3,
  98         DHCPV6_NotOnLink = 4,
  99         DHCPV6_UseMulticast = 5,
 100         DHCPV6_NoPrefixAvail = 6,
 101         _DHCPV6_Status_Max
 102 };
 103
 104 enum dhcpv6_config {
 105         DHCPV6_STRICT_OPTIONS = 1,
 106         DHCPV6_CLIENT_FQDN = 2,
 107         DHCPV6_ACCEPT_RECONFIGURE = 4,
 108 };
 109
 110 typedef int(reply_handler)(enum dhcpv6_msg orig, const int rc,
 111                 const void *opt, const void *end);
 112
 113 // retransmission strategy
 114 struct dhcpv6_retx {
 115         bool delay;
 116         uint8_t init_timeo;
 117         uint16_t max_timeo;
 118         uint8_t max_rc;
 119         char name[8];
 120         reply_handler *handler_reply;
 121         int(*handler_finish)(void);
 122 };
 123
 124 // DHCPv6 Protocol Headers
 125 struct dhcpv6_header {
 126         uint8_t msg_type;
 127         uint8_t tr_id[3];
 128 } __attribute__((packed));
 129
 130 struct dhcpv6_ia_hdr {
 131         uint16_t type;
 132         uint16_t len;
 133         uint32_t iaid;
 134         uint32_t t1;
 135         uint32_t t2;
 136 } _packed;
 137
 138 struct dhcpv6_ia_addr {
 139         uint16_t type;
 140         uint16_t len;
 141         struct in6_addr addr;
 142         uint32_t preferred;
 143         uint32_t valid;
 144 } _packed;
 145
 146 struct dhcpv6_ia_prefix {
 147         uint16_t type;
 148         uint16_t len;
 149         uint32_t preferred;
 150         uint32_t valid;
 151         uint8_t prefix;
 152         struct in6_addr addr;
 153 } _packed;
 154
 155 struct dhcpv6_duid {
 156         uint16_t type;
 157         uint16_t len;
 158         uint16_t duid_type;
 159         uint8_t data[128];
 160 } _packed;
 161
 162 struct dhcpv6_auth_reconfigure {
 163         uint16_t type;
 164         uint16_t len;
 165         uint8_t protocol;
 166         uint8_t algorithm;
 167         uint8_t rdm;
 168         uint64_t replay;
 169         uint8_t reconf_type;
 170         uint8_t key[16];
 171 } _packed;
 172
 173
 174 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
 175         for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
 176                 ((otype) = _o[0] << 8 | _o[1]) && ((odata) = (void*)&_o[4]) &&\
 177                 ((olen) = _o[2] << 8 | _o[3]) + (odata) <= (uint8_t*)(end); \
 178                 _o += 4 + (_o[2] << 8 | _o[3]))
 179
 180
 181 struct dhcpv6_server_cand {
 182         bool has_noaddravail;
 183         bool wants_reconfigure;
 184         int16_t preference;
 185         uint8_t duid_len;
 186         uint8_t duid[130];
 187         uint32_t sol_max_rt;
 188         uint32_t inf_max_rt;
 189         void *ia_na;
 190         void *ia_pd;
 191         size_t ia_na_len;
 192         size_t ia_pd_len;
 193 };
 194
 195
 196 enum odhcp6c_state {
 197         STATE_CLIENT_ID,
 198         STATE_SERVER_ID,
 199         STATE_SERVER_CAND,
 200         STATE_ORO,
 201         STATE_DNS,
 202         STATE_SEARCH,
 203         STATE_IA_NA,
 204         STATE_IA_PD,
 205         STATE_IA_PD_INIT,
 206         STATE_CUSTOM_OPTS,
 207         STATE_SNTP_IP,
 208         STATE_NTP_IP,
 209         STATE_NTP_FQDN,
 210         STATE_SIP_IP,
 211         STATE_SIP_FQDN,
 212         STATE_RA_ROUTE,
 213         STATE_RA_PREFIX,
 214         STATE_RA_DNS,
 215         STATE_AFTR_NAME,
 216         STATE_VENDORCLASS,
 217         STATE_USERCLASS,
 218         _STATE_MAX
 219 };
 220
 221
 222 struct icmp6_opt {
 223         uint8_t type;
 224         uint8_t len;
 225         uint8_t data[6];
 226 };
 227
 228
 229 enum dhcpv6_mode {
 230         DHCPV6_UNKNOWN = -1,
 231         DHCPV6_STATELESS,
 232         DHCPV6_STATEFUL
 233 };
 234
 235 enum odhcp6c_ia_mode {
 236         IA_MODE_NONE,
 237         IA_MODE_TRY,
 238         IA_MODE_FORCE,
 239 };
 240
 241
 242 struct odhcp6c_entry {
 243         struct in6_addr router;
 244         uint16_t length;
 245         int16_t priority;
 246         struct in6_addr target;
 247         uint32_t valid;
 248         uint32_t preferred;
 249         uint32_t t1;
 250         uint32_t t2;
 251         uint16_t class;
 252         uint32_t iaid;
 253 };
 254
 255 struct odhcp6c_request_prefix {
 256         uint32_t iaid;
 257         uint16_t length;
 258 };
 259
 260 int init_dhcpv6(const char *ifname, unsigned int client_options, int sol_timeout);
 261 void dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na, enum odhcp6c_ia_mode pd);
 262 int dhcpv6_request(enum dhcpv6_msg type);
 263 int dhcpv6_poll_reconfigure(void);
 264 int dhcpv6_promote_server_cand(void);
 265
 266 int init_rtnetlink(void);
 267 int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
 268                 uint32_t pref, uint32_t valid);
 269
 270 int script_init(const char *path, const char *ifname);
 271 ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
 272 void script_call(const char *status);
 273 void script_delay_call(const char *status, int timeout);
 274
 275 bool odhcp6c_signal_process(void);
 276 uint64_t odhcp6c_get_milli_time(void);
 277 void odhcp6c_random(void *buf, size_t len);
 278 bool odhcp6c_is_bound(void);
 279
 280 // State manipulation
 281 void odhcp6c_clear_state(enum odhcp6c_state state);
 282 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len);
 283 void odhcp6c_append_state(enum odhcp6c_state state, const void *data, size_t len);
 284 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len);
 285 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len);
 286 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len);
 287 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len);
 288
 289 // Entry manipulation
 290 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new);
 291 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new);
 292 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe);
 293
 294 void odhcp6c_expire(void);
 295 uint32_t odhcp6c_elapsed(void);