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 };
  52
  53 enum dhcpv6_msg {
  54         DHCPV6_MSG_UNKNOWN = 0,
  55         DHCPV6_MSG_SOLICIT = 1,
  56         DHCPV6_MSG_ADVERT = 2,
  57         DHCPV6_MSG_REQUEST = 3,
  58         DHCPV6_MSG_RENEW = 5,
  59         DHCPV6_MSG_REBIND = 6,
  60         DHCPV6_MSG_REPLY = 7,
  61         DHCPV6_MSG_RELEASE = 8,
  62         DHCPV6_MSG_DECLINE = 9,
  63         DHCPV6_MSG_RECONF = 10,
  64         DHCPV6_MSG_INFO_REQ = 11,
  65         _DHCPV6_MSG_MAX
  66 };
  67
  68 enum dhcpv6_status {
  69         DHCPV6_NoAddrsAvail = 2,
  70         DHCPV6_NoPrefixAvail = 6,
  71 };
  72
  73 typedef int(reply_handler)(enum dhcpv6_msg orig,
  74                 const void *opt, const void *end, uint32_t elapsed);
  75
  76 // retransmission strategy
  77 struct dhcpv6_retx {
  78         bool delay;
  79         uint8_t init_timeo;
  80         uint16_t max_timeo;
  81         char name[8];
  82         reply_handler *handler_reply;
  83         int(*handler_finish)(uint32_t elapsed);
  84 };
  85
  86
  87 // DHCPv6 Protocol Headers
  88 struct dhcpv6_header {
  89         uint8_t msg_type;
  90         uint8_t tr_id[3];
  91 } __attribute__((packed));
  92
  93 struct dhcpv6_ia_hdr {
  94         uint16_t type;
  95         uint16_t len;
  96         uint32_t iaid;
  97         uint32_t t1;
  98         uint32_t t2;
  99 } _packed;
 100
 101 struct dhcpv6_ia_addr {
 102         uint16_t type;
 103         uint16_t len;
 104         struct in6_addr addr;
 105         uint32_t preferred;
 106         uint32_t valid;
 107 } _packed;
 108
 109 struct dhcpv6_ia_prefix {
 110         uint16_t type;
 111         uint16_t len;
 112         uint32_t preferred;
 113         uint32_t valid;
 114         uint8_t prefix;
 115         struct in6_addr addr;
 116 } _packed;
 117
 118 struct dhcpv6_duid {
 119         uint16_t type;
 120         uint16_t len;
 121         uint16_t duid_type;
 122         uint8_t data[128];
 123 } _packed;
 124
 125
 126 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
 127         for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
 128                 ((otype) = _o[0] << 8 | _o[1]) && ((odata) = (void*)&_o[4]) &&\
 129                 ((olen) = _o[2] << 8 | _o[3]) + (odata) <= (uint8_t*)(end); \
 130                 _o += 4 + (_o[2] << 8 | _o[3]))
 131
 132
 133 struct dhcpv6_server_cand {
 134         bool has_noaddravail;
 135         bool wants_reconfigure;
 136         int16_t preference;
 137         uint8_t duid_len;
 138         uint8_t duid[130];
 139 };
 140
 141
 142 enum odhcp6c_state {
 143         STATE_CLIENT_ID,
 144         STATE_SERVER_ID,
 145         STATE_SERVER_CAND,
 146         STATE_ORO,
 147         STATE_DNS,
 148         STATE_SEARCH,
 149         STATE_IA_NA,
 150         STATE_IA_PD,
 151         STATE_IA_PD_LOST,
 152         STATE_CUSTOM_OPTS,
 153         _STATE_MAX
 154 };
 155
 156
 157 struct icmp6_opt {
 158         uint8_t type;
 159         uint8_t len;
 160         uint8_t data[6];
 161 };
 162
 163
 164 enum dhcpv6_mode {
 165         DHCPV6_UNKNOWN,
 166         DHCPV6_STATELESS,
 167         DHCPV6_STATEFUL
 168 };
 169
 170
 171 enum odhcp6c_ia_mode {
 172         IA_MODE_NONE,
 173         IA_MODE_TRY,
 174         IA_MODE_FORCE,
 175 };
 176
 177
 178 int init_dhcpv6(const char *ifname, int request_pd);
 179 void dhcpv6_set_ia_na_mode(enum odhcp6c_ia_mode mode);
 180 int dhcpv6_request(enum dhcpv6_msg type);
 181 int dhcpv6_poll_reconfigure(void);
 182 void dhcpv6_remove_addrs(void);
 183
 184 int init_rtnetlink(void);
 185 int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
 186                 time_t pref, time_t valid);
 187
 188 int script_init(const char *path, const char *ifname);
 189 ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
 190 void script_call(const char *status);
 191
 192
 193 // State manipulation
 194 bool odhcp6c_signal_is_pending(void);
 195 uint64_t odhcp6c_get_milli_time(void);
 196 void odhcp6c_clear_state(enum odhcp6c_state state);
 197 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len);
 198 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len);
 199 bool odhcp6c_commit_state(enum odhcp6c_state state, size_t old_len);
 200 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len);
 201