Work around false-positive DAD-hits
[project/odhcp6c.git] / 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_AFTR_NAME = 64,
55 DHCPV6_OPT_PD_EXCLUDE = 67,
56 };
57
58 enum dhcpv6_opt_npt {
59 NTP_SRV_ADDR = 1,
60 NTP_MC_ADDR = 2,
61 NTP_SRV_FQDN = 3
62 };
63
64 enum dhcpv6_msg {
65 DHCPV6_MSG_UNKNOWN = 0,
66 DHCPV6_MSG_SOLICIT = 1,
67 DHCPV6_MSG_ADVERT = 2,
68 DHCPV6_MSG_REQUEST = 3,
69 DHCPV6_MSG_RENEW = 5,
70 DHCPV6_MSG_REBIND = 6,
71 DHCPV6_MSG_REPLY = 7,
72 DHCPV6_MSG_RELEASE = 8,
73 DHCPV6_MSG_DECLINE = 9,
74 DHCPV6_MSG_RECONF = 10,
75 DHCPV6_MSG_INFO_REQ = 11,
76 _DHCPV6_MSG_MAX
77 };
78
79 enum dhcpv6_status {
80 DHCPV6_NoAddrsAvail = 2,
81 DHCPV6_NoPrefixAvail = 6,
82 };
83
84 typedef int(reply_handler)(enum dhcpv6_msg orig,
85 const void *opt, const void *end);
86
87 // retransmission strategy
88 struct dhcpv6_retx {
89 bool delay;
90 uint8_t init_timeo;
91 uint16_t max_timeo;
92 char name[8];
93 reply_handler *handler_reply;
94 int(*handler_finish)(void);
95 };
96
97
98 // DHCPv6 Protocol Headers
99 struct dhcpv6_header {
100 uint8_t msg_type;
101 uint8_t tr_id[3];
102 } __attribute__((packed));
103
104 struct dhcpv6_ia_hdr {
105 uint16_t type;
106 uint16_t len;
107 uint32_t iaid;
108 uint32_t t1;
109 uint32_t t2;
110 } _packed;
111
112 struct dhcpv6_ia_addr {
113 uint16_t type;
114 uint16_t len;
115 struct in6_addr addr;
116 uint32_t preferred;
117 uint32_t valid;
118 } _packed;
119
120 struct dhcpv6_ia_prefix {
121 uint16_t type;
122 uint16_t len;
123 uint32_t preferred;
124 uint32_t valid;
125 uint8_t prefix;
126 struct in6_addr addr;
127 } _packed;
128
129 struct dhcpv6_duid {
130 uint16_t type;
131 uint16_t len;
132 uint16_t duid_type;
133 uint8_t data[128];
134 } _packed;
135
136 struct dhcpv6_auth_reconfigure {
137 uint16_t type;
138 uint16_t len;
139 uint8_t protocol;
140 uint8_t algorithm;
141 uint8_t rdm;
142 uint64_t replay;
143 uint8_t reconf_type;
144 uint8_t key[16];
145 } _packed;
146
147
148 #define dhcpv6_for_each_option(start, end, otype, olen, odata)\
149 for (uint8_t *_o = (uint8_t*)(start); _o + 4 <= (uint8_t*)(end) &&\
150 ((otype) = _o[0] << 8 | _o[1]) && ((odata) = (void*)&_o[4]) &&\
151 ((olen) = _o[2] << 8 | _o[3]) + (odata) <= (uint8_t*)(end); \
152 _o += 4 + (_o[2] << 8 | _o[3]))
153
154
155 struct dhcpv6_server_cand {
156 bool has_noaddravail;
157 bool wants_reconfigure;
158 int16_t preference;
159 uint8_t duid_len;
160 uint8_t duid[130];
161 };
162
163
164 enum odhcp6c_state {
165 STATE_CLIENT_ID,
166 STATE_SERVER_ID,
167 STATE_SERVER_CAND,
168 STATE_ORO,
169 STATE_DNS,
170 STATE_SEARCH,
171 STATE_IA_NA,
172 STATE_IA_PD,
173 STATE_CUSTOM_OPTS,
174 STATE_SNTP_IP,
175 STATE_SNTP_FQDN,
176 STATE_SIP_IP,
177 STATE_SIP_FQDN,
178 STATE_RA_ROUTE,
179 STATE_RA_PREFIX,
180 STATE_RA_DNS,
181 STATE_AFTR_NAME,
182 _STATE_MAX
183 };
184
185
186 struct icmp6_opt {
187 uint8_t type;
188 uint8_t len;
189 uint8_t data[6];
190 };
191
192
193 enum dhcpv6_mode {
194 DHCPV6_UNKNOWN,
195 DHCPV6_STATELESS,
196 DHCPV6_STATEFUL
197 };
198
199
200 enum odhcp6c_ia_mode {
201 IA_MODE_NONE,
202 IA_MODE_TRY,
203 IA_MODE_FORCE,
204 };
205
206
207 struct odhcp6c_entry {
208 struct in6_addr router;
209 uint16_t length;
210 int16_t priority;
211 struct in6_addr target;
212 uint32_t valid;
213 uint32_t preferred;
214 };
215
216
217 int init_dhcpv6(const char *ifname, int request_pd);
218 void dhcpv6_set_ia_na_mode(enum odhcp6c_ia_mode mode);
219 int dhcpv6_request(enum dhcpv6_msg type);
220 int dhcpv6_poll_reconfigure(void);
221
222 int init_rtnetlink(void);
223 int set_rtnetlink_addr(int ifindex, const struct in6_addr *addr,
224 uint32_t pref, uint32_t valid);
225
226 int script_init(const char *path, const char *ifname);
227 ssize_t script_unhexlify(uint8_t *dst, size_t len, const char *src);
228 void script_call(const char *status);
229 void script_delay_call(const char *status, int timeout);
230
231 bool odhcp6c_signal_process(void);
232 uint64_t odhcp6c_get_milli_time(void);
233 void odhcp6c_random(void *buf, size_t len);
234
235 // State manipulation
236 void odhcp6c_clear_state(enum odhcp6c_state state);
237 void odhcp6c_add_state(enum odhcp6c_state state, const void *data, size_t len);
238 size_t odhcp6c_remove_state(enum odhcp6c_state state, size_t offset, size_t len);
239 void* odhcp6c_get_state(enum odhcp6c_state state, size_t *len);
240
241 // Entry manipulation
242 struct odhcp6c_entry* odhcp6c_find_entry(enum odhcp6c_state state, const struct odhcp6c_entry *new);
243 void odhcp6c_update_entry(enum odhcp6c_state state, struct odhcp6c_entry *new);
244 void odhcp6c_update_entry_safe(enum odhcp6c_state state, struct odhcp6c_entry *new, uint32_t safe);
245
246 void odhcp6c_expire(void);
247 uint32_t odhcp6c_elapsed(void);