1 /* vi: set sw=4 ts=4: */
3 * Russ Dill <Russ.Dill@asu.edu> September 2001
4 * Rewritten by Vladimir Oleynik <dzo@simtreas.ru> (C) 2003
6 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
9 #define UDHCP_COMMON_H 1
12 #include "common_bufsiz.h"
13 #include <netinet/udp.h>
14 #include <netinet/ip.h>
16 PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
18 extern const uint8_t MAC_BCAST_ADDR[6] ALIGN2; /* six all-ones */
23 /* DHCP protocol. See RFC 2131 */
24 #define DHCP_MAGIC 0x63825363
25 #define DHCP_OPTIONS_BUFSIZE 308
29 //TODO: rename ciaddr/yiaddr/chaddr
31 uint8_t op; /* BOOTREQUEST or BOOTREPLY */
32 uint8_t htype; /* hardware address type. 1 = 10mb ethernet */
33 uint8_t hlen; /* hardware address length */
34 uint8_t hops; /* used by relay agents only */
35 uint32_t xid; /* unique id */
36 uint16_t secs; /* elapsed since client began acquisition/renewal */
37 uint16_t flags; /* only one flag so far: */
38 #define BROADCAST_FLAG 0x8000 /* "I need broadcast replies" */
39 uint32_t ciaddr; /* client IP (if client is in BOUND, RENEW or REBINDING state) */
40 uint32_t yiaddr; /* 'your' (client) IP address */
41 /* IP address of next server to use in bootstrap, returned in DHCPOFFER, DHCPACK by server */
43 uint32_t gateway_nip; /* aka 'giaddr': relay agent IP address */
44 uint8_t chaddr[16]; /* link-layer client hardware address (MAC) */
45 uint8_t sname[64]; /* server host name (ASCIZ) */
46 uint8_t file[128]; /* boot file name (ASCIZ) */
47 uint32_t cookie; /* fixed first four option bytes (99,130,83,99 dec) */
48 uint8_t options[DHCP_OPTIONS_BUFSIZE + CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS];
50 #define DHCP_PKT_SNAME_LEN 64
51 #define DHCP_PKT_FILE_LEN 128
52 #define DHCP_PKT_SNAME_LEN_STR "64"
53 #define DHCP_PKT_FILE_LEN_STR "128"
55 struct ip_udp_dhcp_packet {
58 struct dhcp_packet data;
61 struct udp_dhcp_packet {
63 struct dhcp_packet data;
67 IP_UDP_DHCP_SIZE = sizeof(struct ip_udp_dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS,
68 UDP_DHCP_SIZE = sizeof(struct udp_dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS,
69 DHCP_SIZE = sizeof(struct dhcp_packet) - CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS,
72 /* Let's see whether compiler understood us right */
73 struct BUG_bad_sizeof_struct_ip_udp_dhcp_packet {
74 char c[IP_UDP_DHCP_SIZE == 576 ? 1 : -1];
84 /* Opts of STRING_HOST type will be sanitized before they are passed
85 * to udhcpc script's environment: */
96 #if ENABLE_FEATURE_UDHCP_RFC3397 || ENABLE_FEATURE_UDHCPC6_RFC3646 || ENABLE_FEATURE_UDHCPC6_RFC4704
97 OPTION_DNS_STRING, /* RFC1035 compressed domain name list */
99 #if ENABLE_FEATURE_UDHCP_RFC3397
103 OPTION_TYPE_MASK = 0x0f,
104 /* Client requests this option by default */
106 /* There can be a list of 1 or more of these */
110 /* DHCP option codes (partial list). See RFC 2132 and
111 * http://www.iana.org/assignments/bootp-dhcp-parameters/
112 * Commented out options are handled by common option machinery,
113 * uncommented ones have special cases (grep for them to see).
115 #define DHCP_PADDING 0x00
116 #define DHCP_SUBNET 0x01
117 //#define DHCP_TIME_OFFSET 0x02 /* (localtime - UTC_time) in seconds. signed */
118 //#define DHCP_ROUTER 0x03
119 //#define DHCP_TIME_SERVER 0x04 /* RFC 868 time server (32-bit, 0 = 1.1.1900) */
120 //#define DHCP_NAME_SERVER 0x05 /* IEN 116 _really_ ancient kind of NS */
121 //#define DHCP_DNS_SERVER 0x06
122 //#define DHCP_LOG_SERVER 0x07 /* port 704 UDP log (not syslog) */
123 //#define DHCP_COOKIE_SERVER 0x08 /* "quote of the day" server */
124 //#define DHCP_LPR_SERVER 0x09
125 #define DHCP_HOST_NAME 0x0c /* 12: either client informs server or server gives name to client */
126 //#define DHCP_BOOT_SIZE 0x0d
127 //#define DHCP_DOMAIN_NAME 0x0f /* 15: server gives domain suffix */
128 //#define DHCP_SWAP_SERVER 0x10
129 //#define DHCP_ROOT_PATH 0x11
130 //#define DHCP_IP_TTL 0x17
131 //#define DHCP_MTU 0x1a
132 //#define DHCP_BROADCAST 0x1c
133 //#define DHCP_ROUTES 0x21
134 //#define DHCP_NIS_DOMAIN 0x28
135 //#define DHCP_NIS_SERVER 0x29
136 //#define DHCP_NTP_SERVER 0x2a
137 //#define DHCP_WINS_SERVER 0x2c
138 #define DHCP_REQUESTED_IP 0x32 /* 50: sent by client if specific IP is wanted */
139 #define DHCP_LEASE_TIME 0x33 /* 51: */
140 #define DHCP_OPTION_OVERLOAD 0x34 /* 52: */
141 #define DHCP_MESSAGE_TYPE 0x35 /* 53: */
142 #define DHCP_SERVER_ID 0x36 /* 54: server's IP */
143 #define DHCP_PARAM_REQ 0x37 /* 55: list of options client wants */
144 //#define DHCP_ERR_MESSAGE 0x38 /* 56: error message when sending NAK etc */
145 #define DHCP_MAX_SIZE 0x39 /* 57: */
146 #define DHCP_VENDOR 0x3c /* 60: client's vendor (a string) */
147 #define DHCP_CLIENT_ID 0x3d /* 61: by default client's MAC addr, but may be arbitrarily long */
148 //#define DHCP_TFTP_SERVER_NAME 0x42 /* 66: same as 'sname' field */
149 //#define DHCP_BOOT_FILE 0x43 /* 67: same as 'file' field */
150 //#define DHCP_USER_CLASS 0x4d /* 77: RFC 3004. set of LASCII strings. "I am a printer" etc */
151 #define DHCP_FQDN 0x51 /* 81: client asks to update DNS to map its FQDN to its new IP */
152 //#define DHCP_PCODE 0x64 /* 100: RFC 4833. IEEE 1003.1 TZ string */
153 //#define DHCP_TCODE 0x65 /* 101: RFC 4833. Reference to the TZ database string */
154 //#define DHCP_DOMAIN_SEARCH 0x77 /* 119: RFC 3397. set of ASCIZ string, DNS-style compressed */
155 //#define DHCP_SIP_SERVERS 0x78 /* 120: RFC 3361. flag byte, then: 0: domain names, 1: IP addrs */
156 //#define DHCP_STATIC_ROUTES 0x79 /* 121: RFC 3442. (mask,ip,router) tuples */
157 //#define DHCP_VLAN_ID 0x84 /* 132: 802.1P VLAN ID */
158 //#define DHCP_VLAN_PRIORITY 0x85 /* 133: 802.1Q VLAN priority */
159 //#define DHCP_PXE_CONF_FILE 0xd1 /* 209: RFC 5071 Configuration file */
160 //#define DHCP_PXE_PATH_PREFIX 0xd2 /* 210: RFC 5071 Path prefix */
161 //#define DHCP_REBOOT_TIME 0xd3 /* 211: RFC 5071 Reboot time */
162 //#define DHCP_MS_STATIC_ROUTES 0xf9 /* 249: Microsoft's pre-RFC 3442 code for 0x79? */
163 //#define DHCP_WPAD 0xfc /* 252: MSIE's Web Proxy Autodiscovery Protocol */
164 #define DHCP_END 0xff /* 255: */
166 /* Offsets in option byte sequence */
170 /* Offsets in option byte sequence for DHCPv6 */
171 #define D6_OPT_CODE 0
173 #define D6_OPT_DATA 4
174 /* Bits in "overload" option */
175 #define OPTION_FIELD 0
177 #define SNAME_FIELD 2
179 /* DHCP_MESSAGE_TYPE values */
180 #define DHCPDISCOVER 1 /* client -> server */
181 #define DHCPOFFER 2 /* client <- server */
182 #define DHCPREQUEST 3 /* client -> server */
183 #define DHCPDECLINE 4 /* client -> server */
184 #define DHCPACK 5 /* client <- server */
185 #define DHCPNAK 6 /* client <- server */
186 #define DHCPRELEASE 7 /* client -> server */
187 #define DHCPINFORM 8 /* client -> server */
188 #define DHCP_MINTYPE DHCPDISCOVER
189 #define DHCP_MAXTYPE DHCPINFORM
191 struct dhcp_optflag {
198 struct option_set *next;
201 #if ENABLE_UDHCPC || ENABLE_UDHCPD
202 extern const struct dhcp_optflag dhcp_optflags[];
203 extern const char dhcp_option_strings[] ALIGN1;
205 extern const uint8_t dhcp_option_lengths[] ALIGN1;
207 unsigned FAST_FUNC udhcp_option_idx(const char *name, const char *option_strings);
209 uint8_t *udhcp_get_option(struct dhcp_packet *packet, int code) FAST_FUNC;
210 /* Same as above + ensures that option length is 4 bytes
211 * (returns NULL if size is different)
213 uint8_t *udhcp_get_option32(struct dhcp_packet *packet, int code) FAST_FUNC;
214 int udhcp_end_option(uint8_t *optionptr) FAST_FUNC;
215 void udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt) FAST_FUNC;
216 #if ENABLE_UDHCPC || ENABLE_UDHCPD
217 void udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data) FAST_FUNC;
219 #if ENABLE_FEATURE_UDHCP_RFC3397 || ENABLE_FEATURE_UDHCPC6_RFC3646 || ENABLE_FEATURE_UDHCPC6_RFC4704
220 char *dname_dec(const uint8_t *cstr, int clen, const char *pre) FAST_FUNC;
221 uint8_t *dname_enc(/*const uint8_t *cstr, int clen,*/ const char *src, int *retlen) FAST_FUNC;
223 struct option_set *udhcp_find_option(struct option_set *opt_list, uint8_t code) FAST_FUNC;
225 // RFC 2131 Table 5: Fields and options used by DHCP clients
227 // Fields 'hops', 'yiaddr', 'siaddr', 'giaddr' are always zero, 'chaddr' is always client's MAC
229 // Field DHCPDISCOVER DHCPINFORM DHCPREQUEST DHCPDECLINE DHCPRELEASE
230 // ----- ------------ ------------ ----------- ----------- -----------
231 // 'xid' selected by client selected by client 'xid' from server selected by client selected by client
233 // 'secs' 0 or seconds since 0 or seconds since 0 or seconds since 0 0
234 // DHCP process started DHCP process started DHCP process started
235 // 'flags' Set 'BROADCAST' Set 'BROADCAST' Set 'BROADCAST' 0 0
236 // flag if client needs flag if client needs flag if client needs
237 // broadcast reply broadcast reply broadcast reply
238 // 'ciaddr' 0 client's IP 0 or client's IP 0 client's IP
239 // (BOUND/RENEW/REBIND)
240 // 'sname' options or sname options or sname options or sname (unused) (unused)
241 // 'file' options or file options or file options or file (unused) (unused)
242 // 'options' options options options message type opt message type opt
244 // Option DHCPDISCOVER DHCPINFORM DHCPREQUEST DHCPDECLINE DHCPRELEASE
245 // ------ ------------ ---------- ----------- ----------- -----------
246 // Requested IP address MAY MUST NOT MUST (in SELECTING MUST MUST NOT
248 // MUST NOT (in BOUND
250 // IP address lease time MAY MUST NOT MAY MUST NOT MUST NOT
251 // Use 'file'/'sname' fields MAY MAY MAY MAY MAY
252 // Client identifier MAY MAY MAY MAY MAY
253 // Vendor class identifier MAY MAY MAY MUST NOT MUST NOT
254 // Server identifier MUST NOT MUST NOT MUST (after SELECTING) MUST MUST
256 // INIT-REBOOT, BOUND,
257 // RENEWING or REBINDING)
258 // Parameter request list MAY MAY MAY MUST NOT MUST NOT
259 // Maximum message size MAY MAY MAY MUST NOT MUST NOT
260 // Message SHOULD NOT SHOULD NOT SHOULD NOT SHOULD SHOULD
261 // Site-specific MAY MAY MAY MUST NOT MUST NOT
262 // All others MAY MAY MAY MUST NOT MUST NOT
266 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
267 # define IF_UDHCP_VERBOSE(...) __VA_ARGS__
268 extern unsigned dhcp_verbose;
269 # define log1(...) do { if (dhcp_verbose >= 1) bb_info_msg(__VA_ARGS__); } while (0)
270 # define log1s(msg) do { if (dhcp_verbose >= 1) bb_simple_info_msg(msg); } while (0)
271 # if CONFIG_UDHCP_DEBUG >= 2
272 void udhcp_dump_packet(struct dhcp_packet *packet) FAST_FUNC;
273 # define log2(...) do { if (dhcp_verbose >= 2) bb_info_msg(__VA_ARGS__); } while (0)
274 # define log2s(msg) do { if (dhcp_verbose >= 2) bb_simple_info_msg(msg); } while (0)
276 # define udhcp_dump_packet(...) ((void)0)
277 # define log2(...) ((void)0)
278 # define log2s(msg) ((void)0)
280 # if CONFIG_UDHCP_DEBUG >= 3
281 # define log3(...) do { if (dhcp_verbose >= 3) bb_info_msg(__VA_ARGS__); } while (0)
282 # define log3s(msg) do { if (dhcp_verbose >= 3) bb_simple_info_msg(msg); } while (0)
284 # define log3(...) ((void)0)
285 # define log3s(msg) ((void)0)
288 # define IF_UDHCP_VERBOSE(...)
289 # define udhcp_dump_packet(...) ((void)0)
290 # define log1(...) ((void)0)
291 # define log1s(msg) ((void)0)
292 # define log2(...) ((void)0)
293 # define log2s(msg) ((void)0)
294 # define log3(...) ((void)0)
295 # define log3s(msg) ((void)0)
298 #if defined(__mips__)
300 * The 'simple' message functions have a negative impact on the size of the
301 * DHCP code when compiled for MIPS, so don't use them in this case.
303 #define bb_simple_info_msg bb_info_msg
304 #define bb_simple_error_msg bb_error_msg
305 #define bb_simple_perror_msg_and_die bb_perror_msg_and_die
310 /*** Other shared functions ***/
312 /* 2nd param is "uint32_t*" */
313 int FAST_FUNC udhcp_str2nip(const char *str, void *arg);
314 /* 2nd param is "struct option_set**" */
316 #define udhcp_str2optset(str, arg, optflags, option_strings, dhcpv6) \
317 udhcp_str2optset(str, arg, optflags, option_strings)
319 int FAST_FUNC udhcp_str2optset(const char *str,
321 const struct dhcp_optflag *optflags,
322 const char *option_strings,
325 #if ENABLE_UDHCPC || ENABLE_UDHCPD
326 void udhcp_init_header(struct dhcp_packet *packet, char type) FAST_FUNC;
329 int udhcp_recv_kernel_packet(struct dhcp_packet *packet, int fd) FAST_FUNC;
331 int udhcp_send_raw_packet(struct dhcp_packet *dhcp_pkt,
332 uint32_t source_nip, int source_port,
333 uint32_t dest_nip, int dest_port, const uint8_t *dest_arp,
334 int ifindex) FAST_FUNC;
336 int udhcp_send_kernel_packet(struct dhcp_packet *dhcp_pkt,
337 uint32_t source_nip, int source_port,
338 uint32_t dest_nip, int dest_port) FAST_FUNC;
340 void udhcp_sp_setup(void) FAST_FUNC;
341 void udhcp_sp_fd_set(struct pollfd *pfds, int extra_fd) FAST_FUNC;
342 int udhcp_sp_read(void) FAST_FUNC;
344 int udhcp_read_interface(const char *interface, int *ifindex, uint32_t *nip, uint8_t *mac) FAST_FUNC;
346 int udhcp_listen_socket(/*uint32_t ip,*/ int port, const char *inf) FAST_FUNC;
348 /* Returns 1 if no reply received */
349 int arpping(uint32_t test_nip,
350 const uint8_t *safe_mac,
353 const char *interface,
354 unsigned timeo) FAST_FUNC;
356 /* note: ip is a pointer to an IPv6 in network order, possibly misaliged */
357 int sprint_nip6(char *dest, /*const char *pre,*/ const uint8_t *ip) FAST_FUNC;
359 POP_SAVED_FUNCTION_VISIBILITY