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 };
  53
  54 enum dhcpv6_opt_npt {
  55         NTP_SRV_ADDR = 1,
  56         NTP_MC_ADDR = 2,
  57         NTP_SRV_FQDN = 3
  58 };
  59
  60 enum dhcpv6_msg {
  61         DHCPV6_MSG_UNKNOWN = 0,
  62         DHCPV6_MSG_SOLICIT = 1,
  63         DHCPV6_MSG_ADVERT = 2,
  64         DHCPV6_MSG_REQUEST = 3,
  65         DHCPV6_MSG_RENEW = 5,
  66         DHCPV6_MSG_REBIND = 6,
  67         DHCPV6_MSG_REPLY = 7,
  68         DHCPV6_MSG_RELEASE = 8,
  69         DHCPV6_MSG_DECLINE = 9,
  70         DHCPV6_MSG_RECONF = 10,
  71         DHCPV6_MSG_INFO_REQ = 11,
  72         _DHCPV6_MSG_MAX
  73 };
  74
  75 enum dhcpv6_status {
  76         DHCPV6_NoAddrsAvail = 2,
  77         DHCPV6_NoPrefixAvail = 6,
  78 };
  79
  80 typedef int(reply_handler)(enum dhcpv6_msg orig,
  81                 const void *opt, const void *end, uint32_t elapsed);
  82
  83 // retransmission strategy
  84 struct dhcpv6_retx {
  85         bool delay;
  86         uint8_t init_timeo;
  87         uint16_t max_timeo;
  88         char name[8];
  89         reply_handler *handler_reply;
  90         int(*handler_finish)(uint32_t elapsed);
  91 };
  92
  93
  94 // DHCPv6 Protocol Headers
  95 struct dhcpv6_header {
  96         uint8_t msg_type;
  97         uint8_t tr_id[3];
  98 } __attribute__((packed));
  99
 100 struct dhcpv6_ia_hdr {
 101         uint16_t type;
 102         uint16_t len;
 103         uint32_t iaid;
 104         uint32_t t1;
 105         uint32_t t2;
 106 } _packed;
 107
 108 struct dhcpv6_ia_addr {
 109         uint16_t type;
 110         uint16_t len;
 111         struct in6_addr addr;
 112         uint32_t preferred;
 113         uint32_t valid;
 114 } _packed;
 115
 116 struct dhcpv6_ia_prefix {
 117         uint16_t type;
 118         uint16_t len;
 119         uint32_t preferred;
 120         uint32_t valid;
 121         uint8_t prefix;
 122         struct in6_addr addr;
 123 } _packed;
 124
 125 struct dhcpv6_duid {
 126         uint16_t type;
 127         uint16_t len;
 128         uint16_t duid_type;
 129         uint8_t data[128];
 130 } _packed;
 131
 132
 133 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
 134         for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
 135                 ((otype) = _o[0] << 8 | _o[1]) && ((odata) = (void*)&_o[4]) &&\
 136                 ((olen) = _o[2] << 8 | _o[3]) + (odata) <= (uint8_t*)(end); \
 137                 _o += 4 + (_o[2] << 8 | _o[3]))
 138
 139
 140 struct dhcpv6_server_cand {
 141         bool has_noaddravail;
 142         bool wants_reconfigure;
 143         int16_t preference;
 144         uint8_t duid_len;
 145         uint8_t duid[130];
 146 };
 147
 148
 149 enum odhcp6c_state {
 150         STATE_CLIENT_ID,
 151         STATE_SERVER_ID,
 152         STATE_SERVER_CAND,
 153         STATE_ORO,
 154         STATE_DNS,
 155         STATE_SEARCH,
 156         STATE_IA_NA,
 157         STATE_IA_PD,
 158         STATE_IA_PD_LOST,
 159         STATE_CUSTOM_OPTS,
 160         STATE_SNTP_IP,
 161         STATE_SNTP_FQDN,
 162         _STATE_MAX
 163 };
 164
 165
 166 struct icmp6_opt {
 167         uint8_t type;
 168         uint8_t len;
 169         uint8_t data[6];
 170 };
 171
 172
 173 enum dhcpv6_mode {
 174         DHCPV6_UNKNOWN,
 175         DHCPV6_STATELESS,
 176         DHCPV6_STATEFUL
 177 };
 178
 179
 180 enum odhcp6c_ia_mode {
 181         IA_MODE_NONE,
 182         IA_MODE_TRY,
 183         IA_MODE_FORCE,
 184 };
 185
 186
 187 int init_dhcpv6(const char *ifname, int request_pd);
 188 void dhcpv6_set_ia_na_mode(enum odhcp6c_ia_mode mode);
 189 int dhcpv6_request(enum dhcpv6_msg type);
 190 int dhcpv6_poll_reconfigure(void);
 191 void dhcpv6_remove_addrs(void);
 192
 193 int init_rtnetlink(void);
 194 int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
 195                 time_t pref, time_t valid);
 196
 197 int script_init(const char *path, const char *ifname);
 198 ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
 199 void script_call(const char *status);
 200
 201
 202 // State manipulation
 203 bool odhcp6c_signal_is_pending(void);
 204 uint64_t odhcp6c_get_milli_time(void);
 205 void odhcp6c_clear_state(enum odhcp6c_state state);
 206 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len);
 207 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len);
 208 bool odhcp6c_commit_state(enum odhcp6c_state state, size_t old_len);
 209 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len);
 210