src/odhcp6c.h

   1 /**
   2  * Copyright (C) 2012-2013 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         DHCPV6_OPT_PD_EXCLUDE = 67,
  55 };
  56
  57 enum dhcpv6_opt_npt {
  58         NTP_SRV_ADDR = 1,
  59         NTP_MC_ADDR = 2,
  60         NTP_SRV_FQDN = 3
  61 };
  62
  63 enum dhcpv6_msg {
  64         DHCPV6_MSG_UNKNOWN = 0,
  65         DHCPV6_MSG_SOLICIT = 1,
  66         DHCPV6_MSG_ADVERT = 2,
  67         DHCPV6_MSG_REQUEST = 3,
  68         DHCPV6_MSG_RENEW = 5,
  69         DHCPV6_MSG_REBIND = 6,
  70         DHCPV6_MSG_REPLY = 7,
  71         DHCPV6_MSG_RELEASE = 8,
  72         DHCPV6_MSG_DECLINE = 9,
  73         DHCPV6_MSG_RECONF = 10,
  74         DHCPV6_MSG_INFO_REQ = 11,
  75         _DHCPV6_MSG_MAX
  76 };
  77
  78 enum dhcpv6_status {
  79         DHCPV6_NoAddrsAvail = 2,
  80         DHCPV6_NoPrefixAvail = 6,
  81 };
  82
  83 typedef int(reply_handler)(enum dhcpv6_msg orig,
  84                 const void *opt, const void *end);
  85
  86 // retransmission strategy
  87 struct dhcpv6_retx {
  88         bool delay;
  89         uint8_t init_timeo;
  90         uint16_t max_timeo;
  91         char name[8];
  92         reply_handler *handler_reply;
  93         int(*handler_finish)(void);
  94 };
  95
  96
  97 // DHCPv6 Protocol Headers
  98 struct dhcpv6_header {
  99         uint8_t msg_type;
 100         uint8_t tr_id[3];
 101 } __attribute__((packed));
 102
 103 struct dhcpv6_ia_hdr {
 104         uint16_t type;
 105         uint16_t len;
 106         uint32_t iaid;
 107         uint32_t t1;
 108         uint32_t t2;
 109 } _packed;
 110
 111 struct dhcpv6_ia_addr {
 112         uint16_t type;
 113         uint16_t len;
 114         struct in6_addr addr;
 115         uint32_t preferred;
 116         uint32_t valid;
 117 } _packed;
 118
 119 struct dhcpv6_ia_prefix {
 120         uint16_t type;
 121         uint16_t len;
 122         uint32_t preferred;
 123         uint32_t valid;
 124         uint8_t prefix;
 125         struct in6_addr addr;
 126 } _packed;
 127
 128 struct dhcpv6_duid {
 129         uint16_t type;
 130         uint16_t len;
 131         uint16_t duid_type;
 132         uint8_t data[128];
 133 } _packed;
 134
 135
 136 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
 137         for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
 138                 ((otype) = _o[0] << 8 | _o[1]) && ((odata) = (void*)&_o[4]) &&\
 139                 ((olen) = _o[2] << 8 | _o[3]) + (odata) <= (uint8_t*)(end); \
 140                 _o += 4 + (_o[2] << 8 | _o[3]))
 141
 142
 143 struct dhcpv6_server_cand {
 144         bool has_noaddravail;
 145         bool wants_reconfigure;
 146         int16_t preference;
 147         uint8_t duid_len;
 148         uint8_t duid[130];
 149 };
 150
 151
 152 enum odhcp6c_state {
 153         STATE_CLIENT_ID,
 154         STATE_SERVER_ID,
 155         STATE_SERVER_CAND,
 156         STATE_ORO,
 157         STATE_DNS,
 158         STATE_SEARCH,
 159         STATE_IA_NA,
 160         STATE_IA_PD,
 161         STATE_CUSTOM_OPTS,
 162         STATE_SNTP_IP,
 163         STATE_SNTP_FQDN,
 164         STATE_SIP_IP,
 165         STATE_SIP_FQDN,
 166         STATE_RA_ROUTE,
 167         STATE_RA_PREFIX,
 168         STATE_RA_DNS,
 169         _STATE_MAX
 170 };
 171
 172
 173 struct icmp6_opt {
 174         uint8_t type;
 175         uint8_t len;
 176         uint8_t data[6];
 177 };
 178
 179
 180 enum dhcpv6_mode {
 181         DHCPV6_UNKNOWN,
 182         DHCPV6_STATELESS,
 183         DHCPV6_STATEFUL
 184 };
 185
 186
 187 enum odhcp6c_ia_mode {
 188         IA_MODE_NONE,
 189         IA_MODE_TRY,
 190         IA_MODE_FORCE,
 191 };
 192
 193
 194 struct odhcp6c_entry {
 195         struct in6_addr router;
 196         uint16_t length;
 197         int16_t priority;
 198         struct in6_addr target;
 199         uint32_t valid;
 200         uint32_t preferred;
 201 };
 202
 203
 204 int init_dhcpv6(const char *ifname, int request_pd);
 205 void dhcpv6_set_ia_na_mode(enum odhcp6c_ia_mode mode);
 206 int dhcpv6_request(enum dhcpv6_msg type);
 207 int dhcpv6_poll_reconfigure(void);
 208
 209 int init_rtnetlink(void);
 210 int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
 211                 uint32_t pref, uint32_t valid);
 212
 213 int script_init(const char *path, const char *ifname);
 214 ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
 215 void script_call(const char *status);
 216
 217 bool odhcp6c_signal_process(void);
 218 uint64_t odhcp6c_get_milli_time(void);
 219 void odhcp6c_random(void *buf, size_t len);
 220
 221 // State manipulation
 222 void odhcp6c_clear_state(enum odhcp6c_state state);
 223 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len);
 224 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len);
 225 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len);
 226
 227 // Entry manipulation
 228 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new);
 229 void odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new);
 230 void odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe);
 231
 232 void odhcp6c_expire(void);