src/odhcp6c.h

   1 /**
   2  * Copyright (C) 2012 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 #ifndef SOL_NETLINK
  25 #define SOL_NETLINK 270
  26 #endif
  27
  28 #define ND_OPT_RECURSIVE_DNS 25
  29 #define ND_OPT_DNSSL 31
  30
  31 enum dhcvp6_opt {
  32         DHCPV6_OPT_CLIENTID = 1,
  33         DHCPV6_OPT_SERVERID = 2,
  34         DHCPV6_OPT_IA_NA = 3,
  35         DHCPV6_OPT_IA_ADDR = 5,
  36         DHCPV6_OPT_ORO = 6,
  37         DHCPV6_OPT_PREF = 7,
  38         DHCPV6_OPT_ELAPSED = 8,
  39         DHCPV6_OPT_RELAY_MSG = 9,
  40         DHCPV6_OPT_AUTH = 11,
  41         DHCPV6_OPT_STATUS = 13,
  42         DHCPV6_OPT_RAPID_COMMIT = 14,
  43         DHCPV6_OPT_RECONF_MESSAGE = 19,
  44         DHCPV6_OPT_RECONF_ACCEPT = 20,
  45         DHCPV6_OPT_DNS_SERVERS = 23,
  46         DHCPV6_OPT_DNS_DOMAIN = 24,
  47         DHCPV6_OPT_IA_PD = 25,
  48         DHCPV6_OPT_IA_PREFIX = 26,
  49         DHCPV6_OPT_INFO_REFRESH = 32,
  50         DHCPV6_OPT_FQDN = 39,
  51         DHCPV6_OPT_NTP_SERVER = 56,
  52         DHCPV6_OPT_SIP_SERVER_D = 21,
  53         DHCPV6_OPT_SIP_SERVER_A = 22,
  54
  55         /* draft-bhandari-dhc-class-based-prefix */
  56         DHCPV6_OPT_PREFIX_CLASS = 200, /* NOT STANDARDIZED! */
  57 };
  58
  59 enum dhcpv6_opt_npt {
  60         NTP_SRV_ADDR = 1,
  61         NTP_MC_ADDR = 2,
  62         NTP_SRV_FQDN = 3
  63 };
  64
  65 enum dhcpv6_msg {
  66         DHCPV6_MSG_UNKNOWN = 0,
  67         DHCPV6_MSG_SOLICIT = 1,
  68         DHCPV6_MSG_ADVERT = 2,
  69         DHCPV6_MSG_REQUEST = 3,
  70         DHCPV6_MSG_RENEW = 5,
  71         DHCPV6_MSG_REBIND = 6,
  72         DHCPV6_MSG_REPLY = 7,
  73         DHCPV6_MSG_RELEASE = 8,
  74         DHCPV6_MSG_DECLINE = 9,
  75         DHCPV6_MSG_RECONF = 10,
  76         DHCPV6_MSG_INFO_REQ = 11,
  77         _DHCPV6_MSG_MAX
  78 };
  79
  80 enum dhcpv6_status {
  81         DHCPV6_NoAddrsAvail = 2,
  82         DHCPV6_NoPrefixAvail = 6,
  83 };
  84
  85 typedef int(reply_handler)(enum dhcpv6_msg orig,
  86                 const void *opt, const void *end);
  87
  88 // retransmission strategy
  89 struct dhcpv6_retx {
  90         bool delay;
  91         uint8_t init_timeo;
  92         uint16_t max_timeo;
  93         char name[8];
  94         reply_handler *handler_reply;
  95         int(*handler_finish)(void);
  96 };
  97
  98
  99 // DHCPv6 Protocol Headers
 100 struct dhcpv6_header {
 101         uint8_t msg_type;
 102         uint8_t tr_id[3];
 103 } __attribute__((packed));
 104
 105 struct dhcpv6_ia_hdr {
 106         uint16_t type;
 107         uint16_t len;
 108         uint32_t iaid;
 109         uint32_t t1;
 110         uint32_t t2;
 111 } _packed;
 112
 113 struct dhcpv6_ia_addr {
 114         uint16_t type;
 115         uint16_t len;
 116         struct in6_addr addr;
 117         uint32_t preferred;
 118         uint32_t valid;
 119 } _packed;
 120
 121 struct dhcpv6_ia_prefix {
 122         uint16_t type;
 123         uint16_t len;
 124         uint32_t preferred;
 125         uint32_t valid;
 126         uint8_t prefix;
 127         struct in6_addr addr;
 128 } _packed;
 129
 130 struct dhcpv6_duid {
 131         uint16_t type;
 132         uint16_t len;
 133         uint16_t duid_type;
 134         uint8_t data[128];
 135 } _packed;
 136
 137 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
 138         for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
 139                 ((otype) = _o[0] << 8 | _o[1]) && ((odata) = (void*)&_o[4]) &&\
 140                 ((olen) = _o[2] << 8 | _o[3]) + (odata) <= (uint8_t*)(end); \
 141                 _o += 4 + (_o[2] << 8 | _o[3]))
 142
 143
 144 struct dhcpv6_server_cand {
 145         bool has_noaddravail;
 146         bool wants_reconfigure;
 147         int16_t preference;
 148         uint8_t duid_len;
 149         uint8_t duid[130];
 150 };
 151
 152
 153 enum odhcp6c_state {
 154         STATE_CLIENT_ID,
 155         STATE_SERVER_ID,
 156         STATE_SERVER_CAND,
 157         STATE_ORO,
 158         STATE_DNS,
 159         STATE_SEARCH,
 160         STATE_IA_NA,
 161         STATE_IA_PD,
 162         STATE_CUSTOM_OPTS,
 163         STATE_SNTP_IP,
 164         STATE_SNTP_FQDN,
 165         STATE_SIP_IP,
 166         STATE_SIP_FQDN,
 167         STATE_RA_ROUTE,
 168         STATE_RA_PREFIX,
 169         STATE_RA_DNS,
 170         _STATE_MAX
 171 };
 172
 173
 174 struct icmp6_opt {
 175         uint8_t type;
 176         uint8_t len;
 177         uint8_t data[6];
 178 };
 179
 180
 181 enum dhcpv6_mode {
 182         DHCPV6_UNKNOWN,
 183         DHCPV6_STATELESS,
 184         DHCPV6_STATEFUL
 185 };
 186
 187
 188 enum odhcp6c_ia_mode {
 189         IA_MODE_NONE,
 190         IA_MODE_TRY,
 191         IA_MODE_FORCE,
 192 };
 193
 194
 195 struct odhcp6c_entry {
 196         struct in6_addr router;
 197         uint16_t length;
 198         int16_t priority;
 199         struct in6_addr target;
 200         uint32_t valid;
 201         uint32_t preferred;
 202         uint32_t prefix_class;
 203 };
 204
 205
 206 int init_dhcpv6(const char *ifname, int request_pd);
 207 void dhcpv6_set_ia_na_mode(enum odhcp6c_ia_mode mode);
 208 int dhcpv6_request(enum dhcpv6_msg type);
 209 int dhcpv6_poll_reconfigure(void);
 210
 211 int init_rtnetlink(void);
 212 int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
 213                 uint32_t pref, uint32_t valid);
 214
 215 int script_init(const char *path, const char *ifname);
 216 ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
 217 void script_call(const char *status);
 218
 219 bool odhcp6c_signal_process(void);
 220 uint64_t odhcp6c_get_milli_time(void);
 221 void odhcp6c_random(void *buf, size_t len);
 222
 223 // State manipulation
 224 void odhcp6c_clear_state(enum odhcp6c_state state);
 225 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len);
 226 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len);
 227 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len);
 228
 229 // Entry manipulation
 230 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new);
 231 void odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new);
 232 void odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe);
 233
 234 void odhcp6c_expire(void);