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 tarball for details.
9 #define UDHCP_COMMON_H 1
12 #include <netinet/udp.h>
13 #include <netinet/ip.h>
15 PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
17 extern const uint8_t MAC_BCAST_ADDR[6]; /* six all-ones */
22 /* DHCP protocol. See RFC 2131 */
23 #define DHCP_MAGIC 0x63825363
24 #define DHCP_OPTIONS_BUFSIZE 308
28 //TODO: rename ciaddr/yiaddr/chaddr
30 uint8_t op; /* BOOTREQUEST or BOOTREPLY */
31 uint8_t htype; /* hardware address type. 1 = 10mb ethernet */
32 uint8_t hlen; /* hardware address length */
33 uint8_t hops; /* used by relay agents only */
34 uint32_t xid; /* unique id */
35 uint16_t secs; /* elapsed since client began acquisition/renewal */
36 uint16_t flags; /* only one flag so far: */
37 #define BROADCAST_FLAG 0x8000 /* "I need broadcast replies" */
38 uint32_t ciaddr; /* client IP (if client is in BOUND, RENEW or REBINDING state) */
39 uint32_t yiaddr; /* 'your' (client) IP address */
40 /* IP address of next server to use in bootstrap, returned in DHCPOFFER, DHCPACK by server */
42 uint32_t gateway_nip; /* relay agent IP address */
43 uint8_t chaddr[16]; /* link-layer client hardware address (MAC) */
44 uint8_t sname[64]; /* server host name (ASCIZ) */
45 uint8_t file[128]; /* boot file name (ASCIZ) */
46 uint32_t cookie; /* fixed first four option bytes (99,130,83,99 dec) */
47 uint8_t options[DHCP_OPTIONS_BUFSIZE + CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS];
49 #define DHCP_PKT_SNAME_LEN 64
50 #define DHCP_PKT_FILE_LEN 128
51 #define DHCP_PKT_SNAME_LEN_STR "64"
52 #define DHCP_PKT_FILE_LEN_STR "128"
54 struct ip_udp_dhcp_packet {
57 struct dhcp_packet data;
60 /* Let's see whether compiler understood us right */
61 struct BUG_bad_sizeof_struct_ip_udp_dhcp_packet {
62 char BUG_bad_sizeof_struct_ip_udp_dhcp_packet
63 [(sizeof(struct ip_udp_dhcp_packet) != 576 + CONFIG_UDHCPC_SLACK_FOR_BUGGY_SERVERS) ? -1 : 1];
81 #if ENABLE_FEATURE_UDHCP_RFC3397
82 OPTION_DNS_STRING, /* RFC1035 compressed domain name list */
86 OPTION_TYPE_MASK = 0x0f,
87 /* Client requests this option by default */
89 /* There can be a list of 1 or more of these */
93 /* DHCP option codes (partial list). See RFC 2132 and
94 * http://www.iana.org/assignments/bootp-dhcp-parameters/
95 * Commented out options are handled by common option machinery,
96 * uncommented ones have spacial cases (grep for them to see).
98 #define DHCP_PADDING 0x00
99 #define DHCP_SUBNET 0x01
100 //#define DHCP_TIME_OFFSET 0x02 /* (localtime - UTC_time) in seconds. signed */
101 //#define DHCP_ROUTER 0x03
102 //#define DHCP_TIME_SERVER 0x04 /* RFC 868 time server (32-bit, 0 = 1.1.1900) */
103 //#define DHCP_NAME_SERVER 0x05 /* IEN 116 _really_ ancient kind of NS */
104 //#define DHCP_DNS_SERVER 0x06
105 //#define DHCP_LOG_SERVER 0x07 /* port 704 UDP log (not syslog)
106 //#define DHCP_COOKIE_SERVER 0x08 /* "quote of the day" server */
107 //#define DHCP_LPR_SERVER 0x09
108 #define DHCP_HOST_NAME 0x0c /* either client informs server or server gives name to client */
109 //#define DHCP_BOOT_SIZE 0x0d
110 //#define DHCP_DOMAIN_NAME 0x0f /* server gives domain suffix */
111 //#define DHCP_SWAP_SERVER 0x10
112 //#define DHCP_ROOT_PATH 0x11
113 //#define DHCP_IP_TTL 0x17
114 //#define DHCP_MTU 0x1a
115 //#define DHCP_BROADCAST 0x1c
116 //#define DHCP_NIS_DOMAIN 0x28
117 //#define DHCP_NIS_SERVER 0x29
118 //#define DHCP_NTP_SERVER 0x2a
119 //#define DHCP_WINS_SERVER 0x2c
120 #define DHCP_REQUESTED_IP 0x32 /* sent by client if specific IP is wanted */
121 #define DHCP_LEASE_TIME 0x33
122 #define DHCP_OPTION_OVERLOAD 0x34
123 #define DHCP_MESSAGE_TYPE 0x35
124 #define DHCP_SERVER_ID 0x36 /* by default server's IP */
125 #define DHCP_PARAM_REQ 0x37 /* list of options client wants */
126 //#define DHCP_ERR_MESSAGE 0x38 /* error message when sending NAK etc */
127 #define DHCP_MAX_SIZE 0x39
128 #define DHCP_VENDOR 0x3c /* client's vendor (a string) */
129 #define DHCP_CLIENT_ID 0x3d /* by default client's MAC addr, but may be arbitrarily long */
130 //#define DHCP_TFTP_SERVER_NAME 0x42 /* same as 'sname' field */
131 //#define DHCP_BOOT_FILE 0x43 /* same as 'file' field */
132 //#define DHCP_USER_CLASS 0x4d /* RFC 3004. set of LASCII strings. "I am a printer" etc */
133 #define DHCP_FQDN 0x51 /* client asks to update DNS to map its FQDN to its new IP */
134 //#define DHCP_DOMAIN_SEARCH 0x77 /* RFC 3397. set of ASCIZ string, DNS-style compressed */
135 //#define DHCP_SIP_SERVERS 0x78 /* RFC 3361. flag byte, then: 0: domain names, 1: IP addrs */
136 //#define DHCP_STATIC_ROUTES 0x79 /* RFC 3442. (mask,ip,router) tuples */
137 //#define DHCP_WPAD 0xfc /* MSIE's Web Proxy Autodiscovery Protocol */
138 #define DHCP_END 0xff
140 /* Offsets in option byte sequence */
144 /* Bits in "overload" option */
145 #define OPTION_FIELD 0
147 #define SNAME_FIELD 2
149 /* DHCP_MESSAGE_TYPE values */
150 #define DHCPDISCOVER 1 /* client -> server */
151 #define DHCPOFFER 2 /* client <- server */
152 #define DHCPREQUEST 3 /* client -> server */
153 #define DHCPDECLINE 4 /* client -> server */
154 #define DHCPACK 5 /* client <- server */
155 #define DHCPNAK 6 /* client <- server */
156 #define DHCPRELEASE 7 /* client -> server */
157 #define DHCPINFORM 8 /* client -> server */
158 #define DHCP_MINTYPE DHCPDISCOVER
159 #define DHCP_MAXTYPE DHCPINFORM
161 struct dhcp_optflag {
168 struct option_set *next;
171 extern const struct dhcp_optflag dhcp_optflags[];
172 extern const char dhcp_option_strings[];
173 extern const uint8_t dhcp_option_lengths[];
175 unsigned FAST_FUNC udhcp_option_idx(const char *name);
177 uint8_t *udhcp_get_option(struct dhcp_packet *packet, int code) FAST_FUNC;
178 int udhcp_end_option(uint8_t *optionptr) FAST_FUNC;
179 void udhcp_add_binary_option(struct dhcp_packet *packet, uint8_t *addopt) FAST_FUNC;
180 void udhcp_add_simple_option(struct dhcp_packet *packet, uint8_t code, uint32_t data) FAST_FUNC;
181 #if ENABLE_FEATURE_UDHCP_RFC3397
182 char *dname_dec(const uint8_t *cstr, int clen, const char *pre) FAST_FUNC;
183 uint8_t *dname_enc(const uint8_t *cstr, int clen, const char *src, int *retlen) FAST_FUNC;
185 struct option_set *udhcp_find_option(struct option_set *opt_list, uint8_t code) FAST_FUNC;
188 // RFC 2131 Table 5: Fields and options used by DHCP clients
190 // Fields 'hops', 'yiaddr', 'siaddr', 'giaddr' are always zero
192 // Field DHCPDISCOVER DHCPINFORM DHCPREQUEST DHCPDECLINE DHCPRELEASE
193 // ----- ------------ ------------ ----------- ----------- -----------
194 // 'xid' selected by client selected by client 'xid' from server selected by client selected by client
196 // 'secs' 0 or seconds since 0 or seconds since 0 or seconds since 0 0
197 // DHCP process started DHCP process started DHCP process started
198 // 'flags' Set 'BROADCAST' Set 'BROADCAST' Set 'BROADCAST' 0 0
199 // flag if client flag if client flag if client
200 // requires broadcast requires broadcast requires broadcast
202 // 'ciaddr' 0 client's IP 0 or client's IP 0 client's IP
203 // (BOUND/RENEW/REBIND)
204 // 'chaddr' client's MAC client's MAC client's MAC client's MAC client's MAC
205 // 'sname' options or sname options or sname options or sname (unused) (unused)
206 // 'file' options or file options or file options or file (unused) (unused)
207 // 'options' options options options message type opt message type opt
209 // Option DHCPDISCOVER DHCPINFORM DHCPREQUEST DHCPDECLINE DHCPRELEASE
210 // ------ ------------ ---------- ----------- ----------- -----------
211 // Requested IP address MAY MUST NOT MUST (in MUST MUST NOT
217 // IP address lease time MAY MUST NOT MAY MUST NOT MUST NOT
218 // Use 'file'/'sname' fields MAY MAY MAY MAY MAY
219 // Client identifier MAY MAY MAY MAY MAY
220 // Vendor class identifier MAY MAY MAY MUST NOT MUST NOT
221 // Server identifier MUST NOT MUST NOT MUST (after MUST MUST
227 // Parameter request list MAY MAY MAY MUST NOT MUST NOT
228 // Maximum message size MAY MAY MAY MUST NOT MUST NOT
229 // Message SHOULD NOT SHOULD NOT SHOULD NOT SHOULD SHOULD
230 // Site-specific MAY MAY MAY MUST NOT MUST NOT
231 // All others MAY MAY MAY MUST NOT MUST NOT
236 #if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 1
237 extern unsigned dhcp_verbose;
238 # define log1(...) do { if (dhcp_verbose >= 1) bb_info_msg(__VA_ARGS__); } while (0)
239 # if CONFIG_UDHCP_DEBUG >= 2
240 void udhcp_dump_packet(struct dhcp_packet *packet) FAST_FUNC;
241 # define log2(...) do { if (dhcp_verbose >= 2) bb_info_msg(__VA_ARGS__); } while (0)
243 # define udhcp_dump_packet(...) ((void)0)
244 # define log2(...) ((void)0)
246 # if CONFIG_UDHCP_DEBUG >= 3
247 # define log3(...) do { if (dhcp_verbose >= 3) bb_info_msg(__VA_ARGS__); } while (0)
249 # define log3(...) ((void)0)
252 # define udhcp_dump_packet(...) ((void)0)
253 # define log1(...) ((void)0)
254 # define log2(...) ((void)0)
255 # define log3(...) ((void)0)
259 /*** Other shared functions ***/
261 /* 2nd param is "uint32_t*" */
262 int FAST_FUNC udhcp_str2nip(const char *str, void *arg);
263 /* 2nd param is "struct option_set**" */
264 int FAST_FUNC udhcp_str2optset(const char *str, void *arg);
266 uint16_t udhcp_checksum(void *addr, int count) FAST_FUNC;
268 void udhcp_init_header(struct dhcp_packet *packet, char type) FAST_FUNC;
270 int udhcp_recv_kernel_packet(struct dhcp_packet *packet, int fd) FAST_FUNC;
272 int udhcp_send_raw_packet(struct dhcp_packet *dhcp_pkt,
273 uint32_t source_ip, int source_port,
274 uint32_t dest_ip, int dest_port, const uint8_t *dest_arp,
275 int ifindex) FAST_FUNC;
277 int udhcp_send_kernel_packet(struct dhcp_packet *dhcp_pkt,
278 uint32_t source_ip, int source_port,
279 uint32_t dest_ip, int dest_port) FAST_FUNC;
281 void udhcp_sp_setup(void) FAST_FUNC;
282 int udhcp_sp_fd_set(fd_set *rfds, int extra_fd) FAST_FUNC;
283 int udhcp_sp_read(const fd_set *rfds) FAST_FUNC;
285 int udhcp_read_interface(const char *interface, int *ifindex, uint32_t *nip, uint8_t *mac) FAST_FUNC;
287 int udhcp_listen_socket(/*uint32_t ip,*/ int port, const char *inf) FAST_FUNC;
289 /* Returns 1 if no reply received */
290 int arpping(uint32_t test_nip,
291 const uint8_t *safe_mac,
294 const char *interface) FAST_FUNC;
296 POP_SAVED_FUNCTION_VISIBILITY