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 #ifdef EXT_CER_ID
  71         /* draft-donley-dhc-cer-id-option-03 */
  72         DHCPV6_OPT_CER_ID = EXT_CER_ID,
  73 #endif
  74 };
  75
  76 enum dhcpv6_opt_npt {
  77         NTP_SRV_ADDR = 1,
  78         NTP_MC_ADDR = 2,
  79         NTP_SRV_FQDN = 3
  80 };
  81
  82 enum dhcpv6_msg {
  83         DHCPV6_MSG_UNKNOWN = 0,
  84         DHCPV6_MSG_SOLICIT = 1,
  85         DHCPV6_MSG_ADVERT = 2,
  86         DHCPV6_MSG_REQUEST = 3,
  87         DHCPV6_MSG_RENEW = 5,
  88         DHCPV6_MSG_REBIND = 6,
  89         DHCPV6_MSG_REPLY = 7,
  90         DHCPV6_MSG_RELEASE = 8,
  91         DHCPV6_MSG_DECLINE = 9,
  92         DHCPV6_MSG_RECONF = 10,
  93         DHCPV6_MSG_INFO_REQ = 11,
  94         _DHCPV6_MSG_MAX
  95 };
  96
  97 enum dhcpv6_status {
  98         DHCPV6_Success = 0,
  99         DHCPV6_UnspecFail = 1,
 100         DHCPV6_NoAddrsAvail = 2,
 101         DHCPV6_NoBinding = 3,
 102         DHCPV6_NotOnLink = 4,
 103         DHCPV6_UseMulticast = 5,
 104         DHCPV6_NoPrefixAvail = 6,
 105         _DHCPV6_Status_Max
 106 };
 107
 108 enum dhcpv6_config {
 109         DHCPV6_STRICT_OPTIONS = 1,
 110         DHCPV6_CLIENT_FQDN = 2,
 111         DHCPV6_ACCEPT_RECONFIGURE = 4,
 112 };
 113
 114 typedef int(reply_handler)(enum dhcpv6_msg orig, const int rc,
 115                 const void *opt, const void *end);
 116
 117 // retransmission strategy
 118 struct dhcpv6_retx {
 119         bool delay;
 120         uint8_t init_timeo;
 121         uint16_t max_timeo;
 122         uint8_t max_rc;
 123         char name[8];
 124         reply_handler *handler_reply;
 125         int(*handler_finish)(void);
 126 };
 127
 128 // DHCPv6 Protocol Headers
 129 struct dhcpv6_header {
 130         uint8_t msg_type;
 131         uint8_t tr_id[3];
 132 } __attribute__((packed));
 133
 134 struct dhcpv6_ia_hdr {
 135         uint16_t type;
 136         uint16_t len;
 137         uint32_t iaid;
 138         uint32_t t1;
 139         uint32_t t2;
 140 } _packed;
 141
 142 struct dhcpv6_ia_addr {
 143         uint16_t type;
 144         uint16_t len;
 145         struct in6_addr addr;
 146         uint32_t preferred;
 147         uint32_t valid;
 148 } _packed;
 149
 150 struct dhcpv6_ia_prefix {
 151         uint16_t type;
 152         uint16_t len;
 153         uint32_t preferred;
 154         uint32_t valid;
 155         uint8_t prefix;
 156         struct in6_addr addr;
 157 } _packed;
 158
 159 struct dhcpv6_duid {
 160         uint16_t type;
 161         uint16_t len;
 162         uint16_t duid_type;
 163         uint8_t data[128];
 164 } _packed;
 165
 166 struct dhcpv6_auth_reconfigure {
 167         uint16_t type;
 168         uint16_t len;
 169         uint8_t protocol;
 170         uint8_t algorithm;
 171         uint8_t rdm;
 172         uint64_t replay;
 173         uint8_t reconf_type;
 174         uint8_t key[16];
 175 } _packed;
 176
 177 struct dhcpv6_cer_id {
 178         uint16_t type;
 179         uint16_t len;
 180         uint16_t reserved;
 181         uint16_t auth_type;
 182         uint8_t auth[16];
 183         struct in6_addr addr;
 184 } _packed;
 185
 186
 187 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
 188         for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
 189                 ((otype) = _o[0] << 8 | _o[1]) && ((odata) = (void*)&_o[4]) &&\
 190                 ((olen) = _o[2] << 8 | _o[3]) + (odata) <= (uint8_t*)(end); \
 191                 _o += 4 + (_o[2] << 8 | _o[3]))
 192
 193
 194 struct dhcpv6_server_cand {
 195         bool has_noaddravail;
 196         bool wants_reconfigure;
 197         int16_t preference;
 198         uint8_t duid_len;
 199         uint8_t duid[130];
 200         uint32_t sol_max_rt;
 201         uint32_t inf_max_rt;
 202         void *ia_na;
 203         void *ia_pd;
 204         size_t ia_na_len;
 205         size_t ia_pd_len;
 206 };
 207
 208
 209 enum odhcp6c_state {
 210         STATE_CLIENT_ID,
 211         STATE_SERVER_ID,
 212         STATE_SERVER_CAND,
 213         STATE_ORO,
 214         STATE_DNS,
 215         STATE_SEARCH,
 216         STATE_IA_NA,
 217         STATE_IA_PD,
 218         STATE_IA_PD_INIT,
 219         STATE_CUSTOM_OPTS,
 220         STATE_SNTP_IP,
 221         STATE_NTP_IP,
 222         STATE_NTP_FQDN,
 223         STATE_SIP_IP,
 224         STATE_SIP_FQDN,
 225         STATE_RA_ROUTE,
 226         STATE_RA_PREFIX,
 227         STATE_RA_DNS,
 228         STATE_AFTR_NAME,
 229         STATE_VENDORCLASS,
 230         STATE_USERCLASS,
 231         STATE_CER,
 232         _STATE_MAX
 233 };
 234
 235
 236 struct icmp6_opt {
 237         uint8_t type;
 238         uint8_t len;
 239         uint8_t data[6];
 240 };
 241
 242
 243 enum dhcpv6_mode {
 244         DHCPV6_UNKNOWN = -1,
 245         DHCPV6_STATELESS,
 246         DHCPV6_STATEFUL
 247 };
 248
 249 enum odhcp6c_ia_mode {
 250         IA_MODE_NONE,
 251         IA_MODE_TRY,
 252         IA_MODE_FORCE,
 253 };
 254
 255
 256 struct odhcp6c_entry {
 257         struct in6_addr router;
 258         uint16_t length;
 259         int16_t priority;
 260         struct in6_addr target;
 261         uint32_t valid;
 262         uint32_t preferred;
 263         uint32_t t1;
 264         uint32_t t2;
 265         uint16_t class;
 266         uint32_t iaid;
 267 };
 268
 269 struct odhcp6c_request_prefix {
 270         uint32_t iaid;
 271         uint16_t length;
 272 };
 273
 274 int init_dhcpv6(const char *ifname, unsigned int client_options, int sol_timeout);
 275 void dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na, enum odhcp6c_ia_mode pd);
 276 int dhcpv6_request(enum dhcpv6_msg type);
 277 int dhcpv6_poll_reconfigure(void);
 278 int dhcpv6_promote_server_cand(void);
 279
 280 int init_rtnetlink(void);
 281 int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
 282                 uint32_t pref, uint32_t valid);
 283
 284 int script_init(const char *path, const char *ifname);
 285 ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
 286 void script_call(const char *status);
 287 void script_delay_call(const char *status, int timeout);
 288
 289 bool odhcp6c_signal_process(void);
 290 uint64_t odhcp6c_get_milli_time(void);
 291 void odhcp6c_random(void *buf, size_t len);
 292 bool odhcp6c_is_bound(void);
 293
 294 // State manipulation
 295 void odhcp6c_clear_state(enum odhcp6c_state state);
 296 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len);
 297 void odhcp6c_append_state(enum odhcp6c_state state, const void *data, size_t len);
 298 void odhcp6c_insert_state(enum odhcp6c_state state, size_t offset, const void *data, size_t len);
 299 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len);
 300 void* odhcp6c_move_state(enum odhcp6c_state state, size_t *len);
 301 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len);
 302
 303 // Entry manipulation
 304 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new);
 305 bool odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new);
 306 bool odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe);
 307
 308 void odhcp6c_expire(void);
 309 uint32_t odhcp6c_elapsed(void);