3 * Dynamic Host Configuration Protocol client
9 * Copyright (c) 2001-2004 Leon Woestenberg <leon.woestenberg@gmx.net>
10 * Copyright (c) 2001-2004 Axon Digital Design B.V., The Netherlands.
11 * All rights reserved.
13 * Redistribution and use in source and binary forms, with or without modification,
14 * are permitted provided that the following conditions are met:
16 * 1. Redistributions of source code must retain the above copyright notice,
17 * this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright notice,
19 * this list of conditions and the following disclaimer in the documentation
20 * and/or other materials provided with the distribution.
21 * 3. The name of the author may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
27 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
28 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
29 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
32 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
35 * This file is a contribution to the lwIP TCP/IP stack.
36 * The Swedish Institute of Computer Science and Adam Dunkels
37 * are specifically granted permission to redistribute this
40 * Author: Leon Woestenberg <leon.woestenberg@gmx.net>
42 * This is a DHCP client for the lwIP TCP/IP stack. It aims to conform
43 * with RFC 2131 and RFC 2132.
46 * - Support for interfaces other than Ethernet (SLIP, PPP, ...)
48 * Please coordinate changes and requests with Leon Woestenberg
49 * <leon.woestenberg@gmx.net>
51 * Integration with your code:
54 * #define DHCP_COARSE_TIMER_SECS (recommended 60 which is a minute)
55 * #define DHCP_FINE_TIMER_MSECS (recommended 500 which equals TCP coarse timer)
57 * Then have your application call dhcp_coarse_tmr() and
58 * dhcp_fine_tmr() on the defined intervals.
60 * dhcp_start(struct netif *netif);
61 * starts a DHCP client instance which configures the interface by
62 * obtaining an IP address lease and maintaining it.
64 * Use dhcp_release(netif) to end the lease and use dhcp_stop(netif)
65 * to remove the DHCP client.
71 #if LWIP_DHCP /* don't build if not configured for use in lwipopts.h */
73 #include "lwip/stats.h"
76 #include "lwip/ip_addr.h"
77 #include "lwip/netif.h"
80 #include "lwip/dhcp.h"
81 #include "lwip/autoip.h"
83 #include "netif/etharp.h"
87 /** Default for DHCP_GLOBAL_XID is 0xABCD0000
88 * This can be changed by defining DHCP_GLOBAL_XID and DHCP_GLOBAL_XID_HEADER, e.g.
89 * #define DHCP_GLOBAL_XID_HEADER "stdlib.h"
90 * #define DHCP_GLOBAL_XID rand()
92 #ifdef DHCP_GLOBAL_XID_HEADER
93 #include DHCP_GLOBAL_XID_HEADER /* include optional starting XID generation prototypes */
96 /** DHCP_OPTION_MAX_MSG_SIZE is set to the MTU
97 * MTU is checked to be big enough in dhcp_start */
98 #define DHCP_MAX_MSG_LEN(netif) (netif->mtu)
99 #define DHCP_MAX_MSG_LEN_MIN_REQUIRED 576
100 /** Minimum length for reply before packet is parsed */
101 #define DHCP_MIN_REPLY_LEN 44
103 #define REBOOT_TRIES 2
105 /** Option handling: options are parsed in dhcp_parse_reply
106 * and saved in an array where other functions can load them from.
107 * This might be moved into the struct dhcp (not necessarily since
108 * lwIP is single-threaded and the array is only used while in recv
110 #define DHCP_OPTION_IDX_OVERLOAD 0
111 #define DHCP_OPTION_IDX_MSG_TYPE 1
112 #define DHCP_OPTION_IDX_SERVER_ID 2
113 #define DHCP_OPTION_IDX_LEASE_TIME 3
114 #define DHCP_OPTION_IDX_T1 4
115 #define DHCP_OPTION_IDX_T2 5
116 #define DHCP_OPTION_IDX_SUBNET_MASK 6
117 #define DHCP_OPTION_IDX_ROUTER 7
118 #define DHCP_OPTION_IDX_DNS_SERVER 8
119 #define DHCP_OPTION_IDX_MAX (DHCP_OPTION_IDX_DNS_SERVER + DNS_MAX_SERVERS)
121 /** Holds the decoded option values, only valid while in dhcp_recv.
122 @todo: move this into struct dhcp? */
123 u32_t dhcp_rx_options_val
[DHCP_OPTION_IDX_MAX
];
124 /** Holds a flag which option was received and is contained in dhcp_rx_options_val,
125 only valid while in dhcp_recv.
126 @todo: move this into struct dhcp? */
127 u8_t dhcp_rx_options_given
[DHCP_OPTION_IDX_MAX
];
129 #define dhcp_option_given(dhcp, idx) (dhcp_rx_options_given[idx] != 0)
130 #define dhcp_got_option(dhcp, idx) (dhcp_rx_options_given[idx] = 1)
131 #define dhcp_clear_option(dhcp, idx) (dhcp_rx_options_given[idx] = 0)
132 #define dhcp_clear_all_options(dhcp) (memset(dhcp_rx_options_given, 0, sizeof(dhcp_rx_options_given)))
133 #define dhcp_get_option_value(dhcp, idx) (dhcp_rx_options_val[idx])
134 #define dhcp_set_option_value(dhcp, idx, val) (dhcp_rx_options_val[idx] = (val))
137 /* DHCP client state machine functions */
138 static err_t
dhcp_discover(struct netif
*netif
);
139 static err_t
dhcp_select(struct netif
*netif
);
140 static void dhcp_bind(struct netif
*netif
);
141 #if DHCP_DOES_ARP_CHECK
142 static err_t
dhcp_decline(struct netif
*netif
);
143 #endif /* DHCP_DOES_ARP_CHECK */
144 static err_t
dhcp_rebind(struct netif
*netif
);
145 static err_t
dhcp_reboot(struct netif
*netif
);
146 static void dhcp_set_state(struct dhcp
*dhcp
, u8_t new_state
);
148 /* receive, unfold, parse and free incoming messages */
149 static void dhcp_recv(void *arg
, struct udp_pcb
*pcb
, struct pbuf
*p
, ip_addr_t
*addr
, u16_t port
);
151 /* set the DHCP timers */
152 static void dhcp_timeout(struct netif
*netif
);
153 static void dhcp_t1_timeout(struct netif
*netif
);
154 static void dhcp_t2_timeout(struct netif
*netif
);
156 /* build outgoing messages */
157 /* create a DHCP message, fill in common headers */
158 static err_t
dhcp_create_msg(struct netif
*netif
, struct dhcp
*dhcp
, u8_t message_type
);
159 /* free a DHCP request */
160 static void dhcp_delete_msg(struct dhcp
*dhcp
);
161 /* add a DHCP option (type, then length in bytes) */
162 static void dhcp_option(struct dhcp
*dhcp
, u8_t option_type
, u8_t option_len
);
163 /* add option values */
164 static void dhcp_option_byte(struct dhcp
*dhcp
, u8_t value
);
165 static void dhcp_option_short(struct dhcp
*dhcp
, u16_t value
);
166 static void dhcp_option_long(struct dhcp
*dhcp
, u32_t value
);
167 /* always add the DHCP options trailer to end and pad */
168 static void dhcp_option_trailer(struct dhcp
*dhcp
);
171 * Back-off the DHCP client (because of a received NAK response).
173 * Back-off the DHCP client because of a received NAK. Receiving a
174 * NAK means the client asked for something non-sensible, for
175 * example when it tries to renew a lease obtained on another network.
177 * We clear any existing set IP address and restart DHCP negotiation
178 * afresh (as per RFC2131 3.2.3).
180 * @param netif the netif under DHCP control
183 dhcp_handle_nak(struct netif
*netif
)
185 struct dhcp
*dhcp
= netif
->dhcp
;
186 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_handle_nak(netif=%p) %c%c%"U16_F
"\n",
187 (void*)netif
, netif
->name
[0], netif
->name
[1], (u16_t
)netif
->num
));
188 /* Set the interface down since the address must no longer be used, as per RFC2131 */
189 netif_set_down(netif
);
190 /* remove IP address from interface */
191 netif_set_ipaddr(netif
, IP_ADDR_ANY
);
192 netif_set_gw(netif
, IP_ADDR_ANY
);
193 netif_set_netmask(netif
, IP_ADDR_ANY
);
194 /* Change to a defined state */
195 dhcp_set_state(dhcp
, DHCP_BACKING_OFF
);
196 /* We can immediately restart discovery */
197 dhcp_discover(netif
);
200 #if DHCP_DOES_ARP_CHECK
202 * Checks if the offered IP address is already in use.
204 * It does so by sending an ARP request for the offered address and
205 * entering CHECKING state. If no ARP reply is received within a small
206 * interval, the address is assumed to be free for use by us.
208 * @param netif the netif under DHCP control
211 dhcp_check(struct netif
*netif
)
213 struct dhcp
*dhcp
= netif
->dhcp
;
216 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_check(netif=%p) %c%c\n", (void *)netif
, (s16_t
)netif
->name
[0],
217 (s16_t
)netif
->name
[1]));
218 dhcp_set_state(dhcp
, DHCP_CHECKING
);
219 /* create an ARP query for the offered IP address, expecting that no host
220 responds, as the IP address should not be in use. */
221 result
= etharp_query(netif
, &dhcp
->offered_ip_addr
, NULL
);
222 if (result
!= ERR_OK
) {
223 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_WARNING
, ("dhcp_check: could not perform ARP query\n"));
227 dhcp
->request_timeout
= (msecs
+ DHCP_FINE_TIMER_MSECS
- 1) / DHCP_FINE_TIMER_MSECS
;
228 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_check(): set request timeout %"U16_F
" msecs\n", msecs
));
230 #endif /* DHCP_DOES_ARP_CHECK */
233 * Remember the configuration offered by a DHCP server.
235 * @param netif the netif under DHCP control
238 dhcp_handle_offer(struct netif
*netif
)
240 struct dhcp
*dhcp
= netif
->dhcp
;
241 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_handle_offer(netif=%p) %c%c%"U16_F
"\n",
242 (void*)netif
, netif
->name
[0], netif
->name
[1], (u16_t
)netif
->num
));
243 /* obtain the server address */
244 if (dhcp_option_given(dhcp
, DHCP_OPTION_IDX_SERVER_ID
)) {
245 ip4_addr_set_u32(&dhcp
->server_ip_addr
, htonl(dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_SERVER_ID
)));
246 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_STATE
, ("dhcp_handle_offer(): server 0x%08"X32_F
"\n",
247 ip4_addr_get_u32(&dhcp
->server_ip_addr
)));
248 /* remember offered address */
249 ip_addr_copy(dhcp
->offered_ip_addr
, dhcp
->msg_in
->yiaddr
);
250 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_STATE
, ("dhcp_handle_offer(): offer for 0x%08"X32_F
"\n",
251 ip4_addr_get_u32(&dhcp
->offered_ip_addr
)));
255 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
,
256 ("dhcp_handle_offer(netif=%p) did not get server ID!\n", (void*)netif
));
261 * Select a DHCP server offer out of all offers.
263 * Simply select the first offer received.
265 * @param netif the netif under DHCP control
266 * @return lwIP specific error (see error.h)
269 dhcp_select(struct netif
*netif
)
271 struct dhcp
*dhcp
= netif
->dhcp
;
275 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_select(netif=%p) %c%c%"U16_F
"\n", (void*)netif
, netif
->name
[0], netif
->name
[1], (u16_t
)netif
->num
));
276 dhcp_set_state(dhcp
, DHCP_REQUESTING
);
278 /* create and initialize the DHCP message header */
279 result
= dhcp_create_msg(netif
, dhcp
, DHCP_REQUEST
);
280 if (result
== ERR_OK
) {
281 dhcp_option(dhcp
, DHCP_OPTION_MAX_MSG_SIZE
, DHCP_OPTION_MAX_MSG_SIZE_LEN
);
282 dhcp_option_short(dhcp
, DHCP_MAX_MSG_LEN(netif
));
284 /* MUST request the offered IP address */
285 dhcp_option(dhcp
, DHCP_OPTION_REQUESTED_IP
, 4);
286 dhcp_option_long(dhcp
, ntohl(ip4_addr_get_u32(&dhcp
->offered_ip_addr
)));
288 dhcp_option(dhcp
, DHCP_OPTION_SERVER_ID
, 4);
289 dhcp_option_long(dhcp
, ntohl(ip4_addr_get_u32(&dhcp
->server_ip_addr
)));
291 dhcp_option(dhcp
, DHCP_OPTION_PARAMETER_REQUEST_LIST
, 4/*num options*/);
292 dhcp_option_byte(dhcp
, DHCP_OPTION_SUBNET_MASK
);
293 dhcp_option_byte(dhcp
, DHCP_OPTION_ROUTER
);
294 dhcp_option_byte(dhcp
, DHCP_OPTION_BROADCAST
);
295 dhcp_option_byte(dhcp
, DHCP_OPTION_DNS_SERVER
);
297 #if LWIP_NETIF_HOSTNAME
298 if (netif
->hostname
!= NULL
) {
299 const char *p
= (const char*)netif
->hostname
;
300 u8_t namelen
= (u8_t
)strlen(p
);
302 LWIP_ASSERT("DHCP: hostname is too long!", namelen
< 255);
303 dhcp_option(dhcp
, DHCP_OPTION_HOSTNAME
, namelen
);
305 dhcp_option_byte(dhcp
, *p
++);
309 #endif /* LWIP_NETIF_HOSTNAME */
311 dhcp_option_trailer(dhcp
);
312 /* shrink the pbuf to the actual content length */
313 pbuf_realloc(dhcp
->p_out
, sizeof(struct dhcp_msg
) - DHCP_OPTIONS_LEN
+ dhcp
->options_out_len
);
315 /* send broadcast to any DHCP server */
316 udp_sendto_if(dhcp
->pcb
, dhcp
->p_out
, IP_ADDR_BROADCAST
, DHCP_SERVER_PORT
, netif
);
317 dhcp_delete_msg(dhcp
);
318 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_select: REQUESTING\n"));
320 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_WARNING
, ("dhcp_select: could not allocate DHCP request\n"));
323 msecs
= (dhcp
->tries
< 6 ? 1 << dhcp
->tries
: 60) * 1000;
324 dhcp
->request_timeout
= (msecs
+ DHCP_FINE_TIMER_MSECS
- 1) / DHCP_FINE_TIMER_MSECS
;
325 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_STATE
, ("dhcp_select(): set request timeout %"U16_F
" msecs\n", msecs
));
330 * The DHCP timer that checks for lease renewal/rebind timeouts.
335 struct netif
*netif
= netif_list
;
336 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_coarse_tmr()\n"));
337 /* iterate through all network interfaces */
338 while (netif
!= NULL
) {
339 /* only act on DHCP configured interfaces */
340 if (netif
->dhcp
!= NULL
) {
341 /* timer is active (non zero), and triggers (zeroes) now? */
342 if (netif
->dhcp
->t2_timeout
-- == 1) {
343 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_coarse_tmr(): t2 timeout\n"));
344 /* this clients' rebind timeout triggered */
345 dhcp_t2_timeout(netif
);
346 /* timer is active (non zero), and triggers (zeroes) now */
347 } else if (netif
->dhcp
->t1_timeout
-- == 1) {
348 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_coarse_tmr(): t1 timeout\n"));
349 /* this clients' renewal timeout triggered */
350 dhcp_t1_timeout(netif
);
353 /* proceed to next netif */
359 * DHCP transaction timeout handling
361 * A DHCP server is expected to respond within a short period of time.
362 * This timer checks whether an outstanding DHCP request is timed out.
367 struct netif
*netif
= netif_list
;
368 /* loop through netif's */
369 while (netif
!= NULL
) {
370 /* only act on DHCP configured interfaces */
371 if (netif
->dhcp
!= NULL
) {
372 /* timer is active (non zero), and is about to trigger now */
373 if (netif
->dhcp
->request_timeout
> 1) {
374 netif
->dhcp
->request_timeout
--;
376 else if (netif
->dhcp
->request_timeout
== 1) {
377 netif
->dhcp
->request_timeout
--;
378 /* { netif->dhcp->request_timeout == 0 } */
379 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_fine_tmr(): request timeout\n"));
380 /* this client's request timeout triggered */
384 /* proceed to next network interface */
390 * A DHCP negotiation transaction, or ARP request, has timed out.
392 * The timer that was started with the DHCP or ARP request has
393 * timed out, indicating no response was received in time.
395 * @param netif the netif under DHCP control
398 dhcp_timeout(struct netif
*netif
)
400 struct dhcp
*dhcp
= netif
->dhcp
;
401 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_timeout()\n"));
402 /* back-off period has passed, or server selection timed out */
403 if ((dhcp
->state
== DHCP_BACKING_OFF
) || (dhcp
->state
== DHCP_SELECTING
)) {
404 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_timeout(): restarting discovery\n"));
405 dhcp_discover(netif
);
406 /* receiving the requested lease timed out */
407 } else if (dhcp
->state
== DHCP_REQUESTING
) {
408 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_timeout(): REQUESTING, DHCP request timed out\n"));
409 if (dhcp
->tries
<= 5) {
412 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_timeout(): REQUESTING, releasing, restarting\n"));
414 dhcp_discover(netif
);
416 #if DHCP_DOES_ARP_CHECK
417 /* received no ARP reply for the offered address (which is good) */
418 } else if (dhcp
->state
== DHCP_CHECKING
) {
419 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_timeout(): CHECKING, ARP request timed out\n"));
420 if (dhcp
->tries
<= 1) {
422 /* no ARP replies on the offered address,
423 looks like the IP address is indeed free */
425 /* bind the interface to the offered address */
428 #endif /* DHCP_DOES_ARP_CHECK */
430 /* did not get response to renew request? */
431 else if (dhcp
->state
== DHCP_RENEWING
) {
432 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_timeout(): RENEWING, DHCP request timed out\n"));
433 /* just retry renewal */
434 /* note that the rebind timer will eventually time-out if renew does not work */
436 /* did not get response to rebind request? */
437 } else if (dhcp
->state
== DHCP_REBINDING
) {
438 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_timeout(): REBINDING, DHCP request timed out\n"));
439 if (dhcp
->tries
<= 8) {
442 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_timeout(): RELEASING, DISCOVERING\n"));
444 dhcp_discover(netif
);
446 } else if (dhcp
->state
== DHCP_REBOOTING
) {
447 if (dhcp
->tries
< REBOOT_TRIES
) {
450 dhcp_discover(netif
);
456 * The renewal period has timed out.
458 * @param netif the netif under DHCP control
461 dhcp_t1_timeout(struct netif
*netif
)
463 struct dhcp
*dhcp
= netif
->dhcp
;
464 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_STATE
, ("dhcp_t1_timeout()\n"));
465 if ((dhcp
->state
== DHCP_REQUESTING
) || (dhcp
->state
== DHCP_BOUND
) ||
466 (dhcp
->state
== DHCP_RENEWING
)) {
467 /* just retry to renew - note that the rebind timer (t2) will
468 * eventually time-out if renew tries fail. */
469 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
,
470 ("dhcp_t1_timeout(): must renew\n"));
471 /* This slightly different to RFC2131: DHCPREQUEST will be sent from state
472 DHCP_RENEWING, not DHCP_BOUND */
478 * The rebind period has timed out.
480 * @param netif the netif under DHCP control
483 dhcp_t2_timeout(struct netif
*netif
)
485 struct dhcp
*dhcp
= netif
->dhcp
;
486 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_t2_timeout()\n"));
487 if ((dhcp
->state
== DHCP_REQUESTING
) || (dhcp
->state
== DHCP_BOUND
) ||
488 (dhcp
->state
== DHCP_RENEWING
)) {
489 /* just retry to rebind */
490 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
,
491 ("dhcp_t2_timeout(): must rebind\n"));
492 /* This slightly different to RFC2131: DHCPREQUEST will be sent from state
493 DHCP_REBINDING, not DHCP_BOUND */
499 * Handle a DHCP ACK packet
501 * @param netif the netif under DHCP control
504 dhcp_handle_ack(struct netif
*netif
)
506 struct dhcp
*dhcp
= netif
->dhcp
;
509 #endif /* LWIP_DNS */
511 /* clear options we might not get from the ACK */
512 ip_addr_set_zero(&dhcp
->offered_sn_mask
);
513 ip_addr_set_zero(&dhcp
->offered_gw_addr
);
514 #if LWIP_DHCP_BOOTP_FILE
515 ip_addr_set_zero(&dhcp
->offered_si_addr
);
516 #endif /* LWIP_DHCP_BOOTP_FILE */
518 /* lease time given? */
519 if (dhcp_option_given(dhcp
, DHCP_OPTION_IDX_LEASE_TIME
)) {
520 /* remember offered lease time */
521 dhcp
->offered_t0_lease
= dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_LEASE_TIME
);
523 /* renewal period given? */
524 if (dhcp_option_given(dhcp
, DHCP_OPTION_IDX_T1
)) {
525 /* remember given renewal period */
526 dhcp
->offered_t1_renew
= dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_T1
);
528 /* calculate safe periods for renewal */
529 dhcp
->offered_t1_renew
= dhcp
->offered_t0_lease
/ 2;
532 /* renewal period given? */
533 if (dhcp_option_given(dhcp
, DHCP_OPTION_IDX_T2
)) {
534 /* remember given rebind period */
535 dhcp
->offered_t2_rebind
= dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_T2
);
537 /* calculate safe periods for rebinding */
538 dhcp
->offered_t2_rebind
= dhcp
->offered_t0_lease
;
541 /* (y)our internet address */
542 ip_addr_copy(dhcp
->offered_ip_addr
, dhcp
->msg_in
->yiaddr
);
544 #if LWIP_DHCP_BOOTP_FILE
545 /* copy boot server address,
546 boot file name copied in dhcp_parse_reply if not overloaded */
547 ip_addr_copy(dhcp
->offered_si_addr
, dhcp
->msg_in
->siaddr
);
548 #endif /* LWIP_DHCP_BOOTP_FILE */
550 /* subnet mask given? */
551 if (dhcp_option_given(dhcp
, DHCP_OPTION_IDX_SUBNET_MASK
)) {
552 /* remember given subnet mask */
553 ip4_addr_set_u32(&dhcp
->offered_sn_mask
, htonl(dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_SUBNET_MASK
)));
554 dhcp
->subnet_mask_given
= 1;
556 dhcp
->subnet_mask_given
= 0;
560 if (dhcp_option_given(dhcp
, DHCP_OPTION_IDX_ROUTER
)) {
561 ip4_addr_set_u32(&dhcp
->offered_gw_addr
, htonl(dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_ROUTER
)));
567 while(dhcp_option_given(dhcp
, DHCP_OPTION_IDX_DNS_SERVER
+ n
) && (n
< DNS_MAX_SERVERS
)) {
569 ip4_addr_set_u32(&dns_addr
, htonl(dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_DNS_SERVER
+ n
)));
570 dns_setserver(n
, &dns_addr
);
573 #endif /* LWIP_DNS */
576 /** Set a statically allocated struct dhcp to work with.
577 * Using this prevents dhcp_start to allocate it using mem_malloc.
579 * @param netif the netif for which to set the struct dhcp
580 * @param dhcp (uninitialised) dhcp struct allocated by the application
583 dhcp_set_struct(struct netif
*netif
, struct dhcp
*dhcp
)
585 LWIP_ASSERT("netif != NULL", netif
!= NULL
);
586 LWIP_ASSERT("dhcp != NULL", dhcp
!= NULL
);
587 LWIP_ASSERT("netif already has a struct dhcp set", netif
->dhcp
== NULL
);
589 /* clear data structure */
590 memset(dhcp
, 0, sizeof(struct dhcp
));
591 /* dhcp_set_state(&dhcp, DHCP_OFF); */
595 /** Removes a struct dhcp from a netif.
597 * ATTENTION: Only use this when not using dhcp_set_struct() to allocate the
598 * struct dhcp since the memory is passed back to the heap.
600 * @param netif the netif from which to remove the struct dhcp
602 void dhcp_cleanup(struct netif
*netif
)
604 LWIP_ASSERT("netif != NULL", netif
!= NULL
);
606 if (netif
->dhcp
!= NULL
) {
607 mem_free(netif
->dhcp
);
613 * Start DHCP negotiation for a network interface.
615 * If no DHCP client instance was attached to this interface,
616 * a new client is created first. If a DHCP client instance
617 * was already present, it restarts negotiation.
619 * @param netif The lwIP network interface
620 * @return lwIP error code
621 * - ERR_OK - No error
622 * - ERR_MEM - Out of memory
625 dhcp_start(struct netif
*netif
)
628 err_t result
= ERR_OK
;
630 LWIP_ERROR("netif != NULL", (netif
!= NULL
), return ERR_ARG
;);
632 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_start(netif=%p) %c%c%"U16_F
"\n", (void*)netif
, netif
->name
[0], netif
->name
[1], (u16_t
)netif
->num
));
633 /* Remove the flag that says this netif is handled by DHCP,
634 it is set when we succeeded starting. */
635 netif
->flags
&= ~NETIF_FLAG_DHCP
;
637 /* check hwtype of the netif */
638 if ((netif
->flags
& NETIF_FLAG_ETHARP
) == 0) {
639 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_start(): No ETHARP netif\n"));
643 /* check MTU of the netif */
644 if (netif
->mtu
< DHCP_MAX_MSG_LEN_MIN_REQUIRED
) {
645 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_start(): Cannot use this netif with DHCP: MTU is too small\n"));
649 /* no DHCP client attached yet? */
651 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_start(): starting new DHCP client\n"));
652 dhcp
= (struct dhcp
*)mem_malloc(sizeof(struct dhcp
));
654 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_start(): could not allocate dhcp\n"));
657 /* store this dhcp client in the netif */
659 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_start(): allocated dhcp"));
660 /* already has DHCP client attached */
662 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_start(): restarting DHCP configuration\n"));
663 if (dhcp
->pcb
!= NULL
) {
664 udp_remove(dhcp
->pcb
);
666 LWIP_ASSERT("pbuf p_out wasn't freed", dhcp
->p_out
== NULL
);
667 LWIP_ASSERT("reply wasn't freed", dhcp
->msg_in
== NULL
);
670 /* clear data structure */
671 memset(dhcp
, 0, sizeof(struct dhcp
));
672 /* dhcp_set_state(&dhcp, DHCP_OFF); */
673 /* allocate UDP PCB */
674 dhcp
->pcb
= udp_new();
675 if (dhcp
->pcb
== NULL
) {
676 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_start(): could not obtain pcb\n"));
679 dhcp
->pcb
->so_options
|= SOF_BROADCAST
;
680 /* set up local and remote port for the pcb */
681 udp_bind(dhcp
->pcb
, IP_ADDR_ANY
, DHCP_CLIENT_PORT
);
682 udp_connect(dhcp
->pcb
, IP_ADDR_ANY
, DHCP_SERVER_PORT
);
683 /* set up the recv callback and argument */
684 udp_recv(dhcp
->pcb
, dhcp_recv
, netif
);
685 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_start(): starting DHCP configuration\n"));
686 /* (re)start the DHCP negotiation */
687 result
= dhcp_discover(netif
);
688 if (result
!= ERR_OK
) {
689 /* free resources allocated above */
693 /* Set the flag that says this netif is handled by DHCP. */
694 netif
->flags
|= NETIF_FLAG_DHCP
;
699 * Inform a DHCP server of our manual configuration.
701 * This informs DHCP servers of our fixed IP address configuration
702 * by sending an INFORM message. It does not involve DHCP address
703 * configuration, it is just here to be nice to the network.
705 * @param netif The lwIP network interface
708 dhcp_inform(struct netif
*netif
)
711 err_t result
= ERR_OK
;
714 LWIP_ERROR("netif != NULL", (netif
!= NULL
), return;);
716 memset(&dhcp
, 0, sizeof(struct dhcp
));
717 dhcp_set_state(&dhcp
, DHCP_INFORM
);
719 if ((netif
->dhcp
!= NULL
) && (netif
->dhcp
->pcb
!= NULL
)) {
720 /* re-use existing pcb */
721 pcb
= netif
->dhcp
->pcb
;
725 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
, ("dhcp_inform(): could not obtain pcb"));
729 dhcp
.pcb
->so_options
|= SOF_BROADCAST
;
730 udp_bind(dhcp
.pcb
, IP_ADDR_ANY
, DHCP_CLIENT_PORT
);
731 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_inform(): created new udp pcb\n"));
733 /* create and initialize the DHCP message header */
734 result
= dhcp_create_msg(netif
, &dhcp
, DHCP_INFORM
);
735 if (result
== ERR_OK
) {
736 dhcp_option(&dhcp
, DHCP_OPTION_MAX_MSG_SIZE
, DHCP_OPTION_MAX_MSG_SIZE_LEN
);
737 dhcp_option_short(&dhcp
, DHCP_MAX_MSG_LEN(netif
));
739 dhcp_option_trailer(&dhcp
);
741 pbuf_realloc(dhcp
.p_out
, sizeof(struct dhcp_msg
) - DHCP_OPTIONS_LEN
+ dhcp
.options_out_len
);
743 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_inform: INFORMING\n"));
744 udp_sendto_if(pcb
, dhcp
.p_out
, IP_ADDR_BROADCAST
, DHCP_SERVER_PORT
, netif
);
745 dhcp_delete_msg(&dhcp
);
747 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
, ("dhcp_inform: could not allocate DHCP request\n"));
750 if (dhcp
.pcb
!= NULL
) {
751 /* otherwise, the existing pcb was used */
752 udp_remove(dhcp
.pcb
);
756 /** Handle a possible change in the network configuration.
758 * This enters the REBOOTING state to verify that the currently bound
759 * address is still valid.
762 dhcp_network_changed(struct netif
*netif
)
764 struct dhcp
*dhcp
= netif
->dhcp
;
767 switch (dhcp
->state
) {
772 netif_set_down(netif
);
781 #if LWIP_DHCP_AUTOIP_COOP
782 if(dhcp
->autoip_coop_state
== DHCP_AUTOIP_COOP_STATE_ON
) {
784 dhcp
->autoip_coop_state
= DHCP_AUTOIP_COOP_STATE_OFF
;
786 #endif /* LWIP_DHCP_AUTOIP_COOP */
787 dhcp_discover(netif
);
792 #if DHCP_DOES_ARP_CHECK
794 * Match an ARP reply with the offered IP address.
796 * @param netif the network interface on which the reply was received
797 * @param addr The IP address we received a reply from
799 void dhcp_arp_reply(struct netif
*netif
, ip_addr_t
*addr
)
801 LWIP_ERROR("netif != NULL", (netif
!= NULL
), return;);
802 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_arp_reply()\n"));
803 /* is a DHCP client doing an ARP check? */
804 if ((netif
->dhcp
!= NULL
) && (netif
->dhcp
->state
== DHCP_CHECKING
)) {
805 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_arp_reply(): CHECKING, arp reply for 0x%08"X32_F
"\n",
806 ip4_addr_get_u32(addr
)));
807 /* did a host respond with the address we
808 were offered by the DHCP server? */
809 if (ip_addr_cmp(addr
, &netif
->dhcp
->offered_ip_addr
)) {
810 /* we will not accept the offered address */
811 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
| LWIP_DBG_LEVEL_WARNING
,
812 ("dhcp_arp_reply(): arp reply matched with offered address, declining\n"));
819 * Decline an offered lease.
821 * Tell the DHCP server we do not accept the offered address.
822 * One reason to decline the lease is when we find out the address
823 * is already in use by another host (through ARP).
825 * @param netif the netif under DHCP control
828 dhcp_decline(struct netif
*netif
)
830 struct dhcp
*dhcp
= netif
->dhcp
;
831 err_t result
= ERR_OK
;
833 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_decline()\n"));
834 dhcp_set_state(dhcp
, DHCP_BACKING_OFF
);
835 /* create and initialize the DHCP message header */
836 result
= dhcp_create_msg(netif
, dhcp
, DHCP_DECLINE
);
837 if (result
== ERR_OK
) {
838 dhcp_option(dhcp
, DHCP_OPTION_REQUESTED_IP
, 4);
839 dhcp_option_long(dhcp
, ntohl(ip4_addr_get_u32(&dhcp
->offered_ip_addr
)));
841 dhcp_option_trailer(dhcp
);
842 /* resize pbuf to reflect true size of options */
843 pbuf_realloc(dhcp
->p_out
, sizeof(struct dhcp_msg
) - DHCP_OPTIONS_LEN
+ dhcp
->options_out_len
);
845 /* per section 4.4.4, broadcast DECLINE messages */
846 udp_sendto_if(dhcp
->pcb
, dhcp
->p_out
, IP_ADDR_BROADCAST
, DHCP_SERVER_PORT
, netif
);
847 dhcp_delete_msg(dhcp
);
848 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_decline: BACKING OFF\n"));
850 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
,
851 ("dhcp_decline: could not allocate DHCP request\n"));
855 dhcp
->request_timeout
= (msecs
+ DHCP_FINE_TIMER_MSECS
- 1) / DHCP_FINE_TIMER_MSECS
;
856 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_decline(): set request timeout %"U16_F
" msecs\n", msecs
));
859 #endif /* DHCP_DOES_ARP_CHECK */
863 * Start the DHCP process, discover a DHCP server.
865 * @param netif the netif under DHCP control
868 dhcp_discover(struct netif
*netif
)
870 struct dhcp
*dhcp
= netif
->dhcp
;
871 err_t result
= ERR_OK
;
873 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_discover()\n"));
874 ip_addr_set_any(&dhcp
->offered_ip_addr
);
875 dhcp_set_state(dhcp
, DHCP_SELECTING
);
876 /* create and initialize the DHCP message header */
877 result
= dhcp_create_msg(netif
, dhcp
, DHCP_DISCOVER
);
878 if (result
== ERR_OK
) {
879 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_discover: making request\n"));
881 dhcp_option(dhcp
, DHCP_OPTION_MAX_MSG_SIZE
, DHCP_OPTION_MAX_MSG_SIZE_LEN
);
882 dhcp_option_short(dhcp
, DHCP_MAX_MSG_LEN(netif
));
884 dhcp_option(dhcp
, DHCP_OPTION_PARAMETER_REQUEST_LIST
, 4/*num options*/);
885 dhcp_option_byte(dhcp
, DHCP_OPTION_SUBNET_MASK
);
886 dhcp_option_byte(dhcp
, DHCP_OPTION_ROUTER
);
887 dhcp_option_byte(dhcp
, DHCP_OPTION_BROADCAST
);
888 dhcp_option_byte(dhcp
, DHCP_OPTION_DNS_SERVER
);
890 dhcp_option_trailer(dhcp
);
892 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_discover: realloc()ing\n"));
893 pbuf_realloc(dhcp
->p_out
, sizeof(struct dhcp_msg
) - DHCP_OPTIONS_LEN
+ dhcp
->options_out_len
);
895 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_discover: sendto(DISCOVER, IP_ADDR_BROADCAST, DHCP_SERVER_PORT)\n"));
896 udp_sendto_if(dhcp
->pcb
, dhcp
->p_out
, IP_ADDR_BROADCAST
, DHCP_SERVER_PORT
, netif
);
897 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_discover: deleting()ing\n"));
898 dhcp_delete_msg(dhcp
);
899 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_discover: SELECTING\n"));
901 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
, ("dhcp_discover: could not allocate DHCP request\n"));
904 #if LWIP_DHCP_AUTOIP_COOP
905 if(dhcp
->tries
>= LWIP_DHCP_AUTOIP_COOP_TRIES
&& dhcp
->autoip_coop_state
== DHCP_AUTOIP_COOP_STATE_OFF
) {
906 dhcp
->autoip_coop_state
= DHCP_AUTOIP_COOP_STATE_ON
;
909 #endif /* LWIP_DHCP_AUTOIP_COOP */
910 msecs
= (dhcp
->tries
< 6 ? 1 << dhcp
->tries
: 60) * 1000;
911 dhcp
->request_timeout
= (msecs
+ DHCP_FINE_TIMER_MSECS
- 1) / DHCP_FINE_TIMER_MSECS
;
912 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_discover(): set request timeout %"U16_F
" msecs\n", msecs
));
918 * Bind the interface to the offered IP address.
920 * @param netif network interface to bind to the offered address
923 dhcp_bind(struct netif
*netif
)
927 ip_addr_t sn_mask
, gw_addr
;
928 LWIP_ERROR("dhcp_bind: netif != NULL", (netif
!= NULL
), return;);
930 LWIP_ERROR("dhcp_bind: dhcp != NULL", (dhcp
!= NULL
), return;);
931 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_bind(netif=%p) %c%c%"U16_F
"\n", (void*)netif
, netif
->name
[0], netif
->name
[1], (u16_t
)netif
->num
));
933 /* temporary DHCP lease? */
934 if (dhcp
->offered_t1_renew
!= 0xffffffffUL
) {
935 /* set renewal period timer */
936 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_bind(): t1 renewal timer %"U32_F
" secs\n", dhcp
->offered_t1_renew
));
937 timeout
= (dhcp
->offered_t1_renew
+ DHCP_COARSE_TIMER_SECS
/ 2) / DHCP_COARSE_TIMER_SECS
;
938 if(timeout
> 0xffff) {
941 dhcp
->t1_timeout
= (u16_t
)timeout
;
942 if (dhcp
->t1_timeout
== 0) {
943 dhcp
->t1_timeout
= 1;
945 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_bind(): set request timeout %"U32_F
" msecs\n", dhcp
->offered_t1_renew
*1000));
947 /* set renewal period timer */
948 if (dhcp
->offered_t2_rebind
!= 0xffffffffUL
) {
949 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_bind(): t2 rebind timer %"U32_F
" secs\n", dhcp
->offered_t2_rebind
));
950 timeout
= (dhcp
->offered_t2_rebind
+ DHCP_COARSE_TIMER_SECS
/ 2) / DHCP_COARSE_TIMER_SECS
;
951 if(timeout
> 0xffff) {
954 dhcp
->t2_timeout
= (u16_t
)timeout
;
955 if (dhcp
->t2_timeout
== 0) {
956 dhcp
->t2_timeout
= 1;
958 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_bind(): set request timeout %"U32_F
" msecs\n", dhcp
->offered_t2_rebind
*1000));
961 if (dhcp
->subnet_mask_given
) {
962 /* copy offered network mask */
963 ip_addr_copy(sn_mask
, dhcp
->offered_sn_mask
);
965 /* subnet mask not given, choose a safe subnet mask given the network class */
966 u8_t first_octet
= ip4_addr1(&dhcp
->offered_ip_addr
);
967 if (first_octet
<= 127) {
968 ip4_addr_set_u32(&sn_mask
, PP_HTONL(0xff000000UL
));
969 } else if (first_octet
>= 192) {
970 ip4_addr_set_u32(&sn_mask
, PP_HTONL(0xffffff00UL
));
972 ip4_addr_set_u32(&sn_mask
, PP_HTONL(0xffff0000UL
));
976 ip_addr_copy(gw_addr
, dhcp
->offered_gw_addr
);
977 /* gateway address not given? */
978 if (ip_addr_isany(&gw_addr
)) {
979 /* copy network address */
980 ip_addr_get_network(&gw_addr
, &dhcp
->offered_ip_addr
, &sn_mask
);
981 /* use first host address on network as gateway */
982 ip4_addr_set_u32(&gw_addr
, ip4_addr_get_u32(&gw_addr
) | PP_HTONL(0x00000001UL
));
985 #if LWIP_DHCP_AUTOIP_COOP
986 if(dhcp
->autoip_coop_state
== DHCP_AUTOIP_COOP_STATE_ON
) {
988 dhcp
->autoip_coop_state
= DHCP_AUTOIP_COOP_STATE_OFF
;
990 #endif /* LWIP_DHCP_AUTOIP_COOP */
992 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_STATE
, ("dhcp_bind(): IP: 0x%08"X32_F
"\n",
993 ip4_addr_get_u32(&dhcp
->offered_ip_addr
)));
994 netif_set_ipaddr(netif
, &dhcp
->offered_ip_addr
);
995 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_STATE
, ("dhcp_bind(): SN: 0x%08"X32_F
"\n",
996 ip4_addr_get_u32(&sn_mask
)));
997 netif_set_netmask(netif
, &sn_mask
);
998 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_STATE
, ("dhcp_bind(): GW: 0x%08"X32_F
"\n",
999 ip4_addr_get_u32(&gw_addr
)));
1000 netif_set_gw(netif
, &gw_addr
);
1001 /* bring the interface up */
1002 netif_set_up(netif
);
1003 /* netif is now bound to DHCP leased address */
1004 dhcp_set_state(dhcp
, DHCP_BOUND
);
1008 * Renew an existing DHCP lease at the involved DHCP server.
1010 * @param netif network interface which must renew its lease
1013 dhcp_renew(struct netif
*netif
)
1015 struct dhcp
*dhcp
= netif
->dhcp
;
1018 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_renew()\n"));
1019 dhcp_set_state(dhcp
, DHCP_RENEWING
);
1021 /* create and initialize the DHCP message header */
1022 result
= dhcp_create_msg(netif
, dhcp
, DHCP_REQUEST
);
1023 if (result
== ERR_OK
) {
1024 dhcp_option(dhcp
, DHCP_OPTION_MAX_MSG_SIZE
, DHCP_OPTION_MAX_MSG_SIZE_LEN
);
1025 dhcp_option_short(dhcp
, DHCP_MAX_MSG_LEN(netif
));
1027 #if LWIP_NETIF_HOSTNAME
1028 if (netif
->hostname
!= NULL
) {
1029 const char *p
= (const char*)netif
->hostname
;
1030 u8_t namelen
= (u8_t
)strlen(p
);
1032 LWIP_ASSERT("DHCP: hostname is too long!", namelen
< 255);
1033 dhcp_option(dhcp
, DHCP_OPTION_HOSTNAME
, namelen
);
1035 dhcp_option_byte(dhcp
, *p
++);
1039 #endif /* LWIP_NETIF_HOSTNAME */
1042 dhcp_option(dhcp
, DHCP_OPTION_REQUESTED_IP
, 4);
1043 dhcp_option_long(dhcp
, ntohl(dhcp
->offered_ip_addr
.addr
));
1047 dhcp_option(dhcp
, DHCP_OPTION_SERVER_ID
, 4);
1048 dhcp_option_long(dhcp
, ntohl(dhcp
->server_ip_addr
.addr
));
1050 /* append DHCP message trailer */
1051 dhcp_option_trailer(dhcp
);
1053 pbuf_realloc(dhcp
->p_out
, sizeof(struct dhcp_msg
) - DHCP_OPTIONS_LEN
+ dhcp
->options_out_len
);
1055 udp_sendto_if(dhcp
->pcb
, dhcp
->p_out
, &dhcp
->server_ip_addr
, DHCP_SERVER_PORT
, netif
);
1056 dhcp_delete_msg(dhcp
);
1058 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_renew: RENEWING\n"));
1060 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
, ("dhcp_renew: could not allocate DHCP request\n"));
1063 /* back-off on retries, but to a maximum of 20 seconds */
1064 msecs
= dhcp
->tries
< 10 ? dhcp
->tries
* 2000 : 20 * 1000;
1065 dhcp
->request_timeout
= (msecs
+ DHCP_FINE_TIMER_MSECS
- 1) / DHCP_FINE_TIMER_MSECS
;
1066 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_renew(): set request timeout %"U16_F
" msecs\n", msecs
));
1071 * Rebind with a DHCP server for an existing DHCP lease.
1073 * @param netif network interface which must rebind with a DHCP server
1076 dhcp_rebind(struct netif
*netif
)
1078 struct dhcp
*dhcp
= netif
->dhcp
;
1081 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_rebind()\n"));
1082 dhcp_set_state(dhcp
, DHCP_REBINDING
);
1084 /* create and initialize the DHCP message header */
1085 result
= dhcp_create_msg(netif
, dhcp
, DHCP_REQUEST
);
1086 if (result
== ERR_OK
) {
1087 dhcp_option(dhcp
, DHCP_OPTION_MAX_MSG_SIZE
, DHCP_OPTION_MAX_MSG_SIZE_LEN
);
1088 dhcp_option_short(dhcp
, DHCP_MAX_MSG_LEN(netif
));
1090 #if LWIP_NETIF_HOSTNAME
1091 if (netif
->hostname
!= NULL
) {
1092 const char *p
= (const char*)netif
->hostname
;
1093 u8_t namelen
= (u8_t
)strlen(p
);
1095 LWIP_ASSERT("DHCP: hostname is too long!", namelen
< 255);
1096 dhcp_option(dhcp
, DHCP_OPTION_HOSTNAME
, namelen
);
1098 dhcp_option_byte(dhcp
, *p
++);
1102 #endif /* LWIP_NETIF_HOSTNAME */
1105 dhcp_option(dhcp
, DHCP_OPTION_REQUESTED_IP
, 4);
1106 dhcp_option_long(dhcp
, ntohl(dhcp
->offered_ip_addr
.addr
));
1108 dhcp_option(dhcp
, DHCP_OPTION_SERVER_ID
, 4);
1109 dhcp_option_long(dhcp
, ntohl(dhcp
->server_ip_addr
.addr
));
1112 dhcp_option_trailer(dhcp
);
1114 pbuf_realloc(dhcp
->p_out
, sizeof(struct dhcp_msg
) - DHCP_OPTIONS_LEN
+ dhcp
->options_out_len
);
1116 /* broadcast to server */
1117 udp_sendto_if(dhcp
->pcb
, dhcp
->p_out
, IP_ADDR_BROADCAST
, DHCP_SERVER_PORT
, netif
);
1118 dhcp_delete_msg(dhcp
);
1119 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_rebind: REBINDING\n"));
1121 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
, ("dhcp_rebind: could not allocate DHCP request\n"));
1124 msecs
= dhcp
->tries
< 10 ? dhcp
->tries
* 1000 : 10 * 1000;
1125 dhcp
->request_timeout
= (msecs
+ DHCP_FINE_TIMER_MSECS
- 1) / DHCP_FINE_TIMER_MSECS
;
1126 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_rebind(): set request timeout %"U16_F
" msecs\n", msecs
));
1131 * Enter REBOOTING state to verify an existing lease
1133 * @param netif network interface which must reboot
1136 dhcp_reboot(struct netif
*netif
)
1138 struct dhcp
*dhcp
= netif
->dhcp
;
1141 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_reboot()\n"));
1142 dhcp_set_state(dhcp
, DHCP_REBOOTING
);
1144 /* create and initialize the DHCP message header */
1145 result
= dhcp_create_msg(netif
, dhcp
, DHCP_REQUEST
);
1146 if (result
== ERR_OK
) {
1147 dhcp_option(dhcp
, DHCP_OPTION_MAX_MSG_SIZE
, DHCP_OPTION_MAX_MSG_SIZE_LEN
);
1148 dhcp_option_short(dhcp
, 576);
1150 dhcp_option(dhcp
, DHCP_OPTION_REQUESTED_IP
, 4);
1151 dhcp_option_long(dhcp
, ntohl(ip4_addr_get_u32(&dhcp
->offered_ip_addr
)));
1153 dhcp_option_trailer(dhcp
);
1155 pbuf_realloc(dhcp
->p_out
, sizeof(struct dhcp_msg
) - DHCP_OPTIONS_LEN
+ dhcp
->options_out_len
);
1157 /* broadcast to server */
1158 udp_sendto_if(dhcp
->pcb
, dhcp
->p_out
, IP_ADDR_BROADCAST
, DHCP_SERVER_PORT
, netif
);
1159 dhcp_delete_msg(dhcp
);
1160 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_reboot: REBOOTING\n"));
1162 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
, ("dhcp_reboot: could not allocate DHCP request\n"));
1165 msecs
= dhcp
->tries
< 10 ? dhcp
->tries
* 1000 : 10 * 1000;
1166 dhcp
->request_timeout
= (msecs
+ DHCP_FINE_TIMER_MSECS
- 1) / DHCP_FINE_TIMER_MSECS
;
1167 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_reboot(): set request timeout %"U16_F
" msecs\n", msecs
));
1173 * Release a DHCP lease.
1175 * @param netif network interface which must release its lease
1178 dhcp_release(struct netif
*netif
)
1180 struct dhcp
*dhcp
= netif
->dhcp
;
1183 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_release()\n"));
1185 /* idle DHCP client */
1186 dhcp_set_state(dhcp
, DHCP_OFF
);
1187 /* clean old DHCP offer */
1188 ip_addr_set_zero(&dhcp
->server_ip_addr
);
1189 ip_addr_set_zero(&dhcp
->offered_ip_addr
);
1190 ip_addr_set_zero(&dhcp
->offered_sn_mask
);
1191 ip_addr_set_zero(&dhcp
->offered_gw_addr
);
1192 #if LWIP_DHCP_BOOTP_FILE
1193 ip_addr_set_zero(&dhcp
->offered_si_addr
);
1194 #endif /* LWIP_DHCP_BOOTP_FILE */
1195 dhcp
->offered_t0_lease
= dhcp
->offered_t1_renew
= dhcp
->offered_t2_rebind
= 0;
1197 /* create and initialize the DHCP message header */
1198 result
= dhcp_create_msg(netif
, dhcp
, DHCP_RELEASE
);
1199 if (result
== ERR_OK
) {
1200 dhcp_option_trailer(dhcp
);
1202 pbuf_realloc(dhcp
->p_out
, sizeof(struct dhcp_msg
) - DHCP_OPTIONS_LEN
+ dhcp
->options_out_len
);
1204 udp_sendto_if(dhcp
->pcb
, dhcp
->p_out
, &dhcp
->server_ip_addr
, DHCP_SERVER_PORT
, netif
);
1205 dhcp_delete_msg(dhcp
);
1206 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_release: RELEASED, DHCP_OFF\n"));
1208 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
, ("dhcp_release: could not allocate DHCP request\n"));
1211 msecs
= dhcp
->tries
< 10 ? dhcp
->tries
* 1000 : 10 * 1000;
1212 dhcp
->request_timeout
= (msecs
+ DHCP_FINE_TIMER_MSECS
- 1) / DHCP_FINE_TIMER_MSECS
;
1213 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_STATE
, ("dhcp_release(): set request timeout %"U16_F
" msecs\n", msecs
));
1214 /* bring the interface down */
1215 netif_set_down(netif
);
1216 /* remove IP address from interface */
1217 netif_set_ipaddr(netif
, IP_ADDR_ANY
);
1218 netif_set_gw(netif
, IP_ADDR_ANY
);
1219 netif_set_netmask(netif
, IP_ADDR_ANY
);
1225 * Remove the DHCP client from the interface.
1227 * @param netif The network interface to stop DHCP on
1230 dhcp_stop(struct netif
*netif
)
1233 LWIP_ERROR("dhcp_stop: netif != NULL", (netif
!= NULL
), return;);
1235 /* Remove the flag that says this netif is handled by DHCP. */
1236 netif
->flags
&= ~NETIF_FLAG_DHCP
;
1238 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_stop()\n"));
1239 /* netif is DHCP configured? */
1241 #if LWIP_DHCP_AUTOIP_COOP
1242 if(dhcp
->autoip_coop_state
== DHCP_AUTOIP_COOP_STATE_ON
) {
1244 dhcp
->autoip_coop_state
= DHCP_AUTOIP_COOP_STATE_OFF
;
1246 #endif /* LWIP_DHCP_AUTOIP_COOP */
1248 if (dhcp
->pcb
!= NULL
) {
1249 udp_remove(dhcp
->pcb
);
1252 LWIP_ASSERT("reply wasn't freed", dhcp
->msg_in
== NULL
);
1253 dhcp_set_state(dhcp
, DHCP_OFF
);
1258 * Set the DHCP state of a DHCP client.
1260 * If the state changed, reset the number of tries.
1263 dhcp_set_state(struct dhcp
*dhcp
, u8_t new_state
)
1265 if (new_state
!= dhcp
->state
) {
1266 dhcp
->state
= new_state
;
1268 dhcp
->request_timeout
= 0;
1273 * Concatenate an option type and length field to the outgoing
1278 dhcp_option(struct dhcp
*dhcp
, u8_t option_type
, u8_t option_len
)
1280 LWIP_ASSERT("dhcp_option: dhcp->options_out_len + 2 + option_len <= DHCP_OPTIONS_LEN", dhcp
->options_out_len
+ 2U + option_len
<= DHCP_OPTIONS_LEN
);
1281 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = option_type
;
1282 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = option_len
;
1285 * Concatenate a single byte to the outgoing DHCP message.
1289 dhcp_option_byte(struct dhcp
*dhcp
, u8_t value
)
1291 LWIP_ASSERT("dhcp_option_byte: dhcp->options_out_len < DHCP_OPTIONS_LEN", dhcp
->options_out_len
< DHCP_OPTIONS_LEN
);
1292 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = value
;
1296 dhcp_option_short(struct dhcp
*dhcp
, u16_t value
)
1298 LWIP_ASSERT("dhcp_option_short: dhcp->options_out_len + 2 <= DHCP_OPTIONS_LEN", dhcp
->options_out_len
+ 2U <= DHCP_OPTIONS_LEN
);
1299 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = (u8_t
)((value
& 0xff00U
) >> 8);
1300 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = (u8_t
) (value
& 0x00ffU
);
1304 dhcp_option_long(struct dhcp
*dhcp
, u32_t value
)
1306 LWIP_ASSERT("dhcp_option_long: dhcp->options_out_len + 4 <= DHCP_OPTIONS_LEN", dhcp
->options_out_len
+ 4U <= DHCP_OPTIONS_LEN
);
1307 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = (u8_t
)((value
& 0xff000000UL
) >> 24);
1308 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = (u8_t
)((value
& 0x00ff0000UL
) >> 16);
1309 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = (u8_t
)((value
& 0x0000ff00UL
) >> 8);
1310 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = (u8_t
)((value
& 0x000000ffUL
));
1314 * Extract the DHCP message and the DHCP options.
1316 * Extract the DHCP message and the DHCP options, each into a contiguous
1317 * piece of memory. As a DHCP message is variable sized by its options,
1318 * and also allows overriding some fields for options, the easy approach
1319 * is to first unfold the options into a conitguous piece of memory, and
1320 * use that further on.
1324 dhcp_parse_reply(struct dhcp
*dhcp
, struct pbuf
*p
)
1330 u16_t options_idx_max
;
1332 int parse_file_as_options
= 0;
1333 int parse_sname_as_options
= 0;
1335 /* clear received options */
1336 dhcp_clear_all_options(dhcp
);
1337 /* check that beginning of dhcp_msg (up to and including chaddr) is in first pbuf */
1338 if (p
->len
< DHCP_SNAME_OFS
) {
1341 dhcp
->msg_in
= (struct dhcp_msg
*)p
->payload
;
1342 #if LWIP_DHCP_BOOTP_FILE
1343 /* clear boot file name */
1344 dhcp
->boot_file_name
[0] = 0;
1345 #endif /* LWIP_DHCP_BOOTP_FILE */
1349 /* start with options field */
1350 options_idx
= DHCP_OPTIONS_OFS
;
1351 /* parse options to the end of the received packet */
1352 options_idx_max
= p
->tot_len
;
1355 while((q
!= NULL
) && (options_idx
>= q
->len
)) {
1356 options_idx
-= q
->len
;
1357 options_idx_max
-= q
->len
;
1363 offset
= options_idx
;
1364 offset_max
= options_idx_max
;
1365 options
= (u8_t
*)q
->payload
;
1366 /* at least 1 byte to read and no end marker, then at least 3 bytes to read? */
1367 while((q
!= NULL
) && (options
[offset
] != DHCP_OPTION_END
) && (offset
< offset_max
)) {
1368 u8_t op
= options
[offset
];
1370 u8_t decode_len
= 0;
1371 int decode_idx
= -1;
1372 u16_t val_offset
= offset
+ 2;
1373 /* len byte might be in the next pbuf */
1374 if (offset
+ 1 < q
->len
) {
1375 len
= options
[offset
+ 1];
1377 len
= (q
->next
!= NULL
? ((u8_t
*)q
->next
->payload
)[0] : 0);
1379 /* LWIP_DEBUGF(DHCP_DEBUG, ("msg_offset=%"U16_F", q->len=%"U16_F, msg_offset, q->len)); */
1382 /* case(DHCP_OPTION_END): handled above */
1383 case(DHCP_OPTION_PAD
):
1384 /* special option: no len encoded */
1385 decode_len
= len
= 0;
1386 /* will be increased below */
1389 case(DHCP_OPTION_SUBNET_MASK
):
1390 LWIP_ASSERT("len == 4", len
== 4);
1391 decode_idx
= DHCP_OPTION_IDX_SUBNET_MASK
;
1393 case(DHCP_OPTION_ROUTER
):
1394 decode_len
= 4; /* only copy the first given router */
1395 LWIP_ASSERT("len >= decode_len", len
>= decode_len
);
1396 decode_idx
= DHCP_OPTION_IDX_ROUTER
;
1398 case(DHCP_OPTION_DNS_SERVER
):
1399 /* special case: there might be more than one server */
1400 LWIP_ASSERT("len % 4 == 0", len
% 4 == 0);
1401 /* limit number of DNS servers */
1402 decode_len
= LWIP_MIN(len
, 4 * DNS_MAX_SERVERS
);
1403 LWIP_ASSERT("len >= decode_len", len
>= decode_len
);
1404 decode_idx
= DHCP_OPTION_IDX_DNS_SERVER
;
1406 case(DHCP_OPTION_LEASE_TIME
):
1407 LWIP_ASSERT("len == 4", len
== 4);
1408 decode_idx
= DHCP_OPTION_IDX_LEASE_TIME
;
1410 case(DHCP_OPTION_OVERLOAD
):
1411 LWIP_ASSERT("len == 1", len
== 1);
1412 decode_idx
= DHCP_OPTION_IDX_OVERLOAD
;
1414 case(DHCP_OPTION_MESSAGE_TYPE
):
1415 LWIP_ASSERT("len == 1", len
== 1);
1416 decode_idx
= DHCP_OPTION_IDX_MSG_TYPE
;
1418 case(DHCP_OPTION_SERVER_ID
):
1419 LWIP_ASSERT("len == 4", len
== 4);
1420 decode_idx
= DHCP_OPTION_IDX_SERVER_ID
;
1422 case(DHCP_OPTION_T1
):
1423 LWIP_ASSERT("len == 4", len
== 4);
1424 decode_idx
= DHCP_OPTION_IDX_T1
;
1426 case(DHCP_OPTION_T2
):
1427 LWIP_ASSERT("len == 4", len
== 4);
1428 decode_idx
= DHCP_OPTION_IDX_T2
;
1432 LWIP_DEBUGF(DHCP_DEBUG
, ("skipping option %"U16_F
" in options\n", op
));
1436 if (decode_len
> 0) {
1440 LWIP_ASSERT("check decode_idx", decode_idx
>= 0 && decode_idx
< DHCP_OPTION_IDX_MAX
);
1441 LWIP_ASSERT("option already decoded", !dhcp_option_given(dhcp
, decode_idx
));
1442 copy_len
= LWIP_MIN(decode_len
, 4);
1443 pbuf_copy_partial(q
, &value
, copy_len
, val_offset
);
1444 if (decode_len
> 4) {
1445 /* decode more than one u32_t */
1446 LWIP_ASSERT("decode_len % 4 == 0", decode_len
% 4 == 0);
1447 dhcp_got_option(dhcp
, decode_idx
);
1448 dhcp_set_option_value(dhcp
, decode_idx
, htonl(value
));
1453 } else if (decode_len
== 4) {
1454 value
= ntohl(value
);
1456 LWIP_ASSERT("invalid decode_len", decode_len
== 1);
1457 value
= ((u8_t
*)&value
)[0];
1459 dhcp_got_option(dhcp
, decode_idx
);
1460 dhcp_set_option_value(dhcp
, decode_idx
, value
);
1462 if (offset
>= q
->len
) {
1464 offset_max
-= q
->len
;
1466 options
= (u8_t
*)q
->payload
;
1469 /* is this an overloaded message? */
1470 if (dhcp_option_given(dhcp
, DHCP_OPTION_IDX_OVERLOAD
)) {
1471 u32_t overload
= dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_OVERLOAD
);
1472 dhcp_clear_option(dhcp
, DHCP_OPTION_IDX_OVERLOAD
);
1473 if (overload
== DHCP_OVERLOAD_FILE
) {
1474 parse_file_as_options
= 1;
1475 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("overloaded file field\n"));
1476 } else if (overload
== DHCP_OVERLOAD_SNAME
) {
1477 parse_sname_as_options
= 1;
1478 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("overloaded sname field\n"));
1479 } else if (overload
== DHCP_OVERLOAD_SNAME_FILE
) {
1480 parse_sname_as_options
= 1;
1481 parse_file_as_options
= 1;
1482 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("overloaded sname and file field\n"));
1484 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("invalid overload option: %d\n", (int)overload
));
1486 #if LWIP_DHCP_BOOTP_FILE
1487 if (!parse_file_as_options
) {
1488 /* only do this for ACK messages */
1489 if (dhcp_option_given(dhcp
, DHCP_OPTION_IDX_MSG_TYPE
) &&
1490 (dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_MSG_TYPE
) == DHCP_ACK
))
1491 /* copy bootp file name, don't care for sname (server hostname) */
1492 pbuf_copy_partial(p
, dhcp
->boot_file_name
, DHCP_FILE_LEN
-1, DHCP_FILE_OFS
);
1493 /* make sure the string is really NULL-terminated */
1494 dhcp
->boot_file_name
[DHCP_FILE_LEN
-1] = 0;
1496 #endif /* LWIP_DHCP_BOOTP_FILE */
1498 if (parse_file_as_options
) {
1499 /* if both are overloaded, parse file first and then sname (RFC 2131 ch. 4.1) */
1500 parse_file_as_options
= 0;
1501 options_idx
= DHCP_FILE_OFS
;
1502 options_idx_max
= DHCP_FILE_OFS
+ DHCP_FILE_LEN
;
1504 } else if (parse_sname_as_options
) {
1505 parse_sname_as_options
= 0;
1506 options_idx
= DHCP_SNAME_OFS
;
1507 options_idx_max
= DHCP_SNAME_OFS
+ DHCP_SNAME_LEN
;
1514 * If an incoming DHCP message is in response to us, then trigger the state machine
1517 dhcp_recv(void *arg
, struct udp_pcb
*pcb
, struct pbuf
*p
, ip_addr_t
*addr
, u16_t port
)
1519 struct netif
*netif
= (struct netif
*)arg
;
1520 struct dhcp
*dhcp
= netif
->dhcp
;
1521 struct dhcp_msg
*reply_msg
= (struct dhcp_msg
*)p
->payload
;
1524 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("dhcp_recv(pbuf = %p) from DHCP server %"U16_F
".%"U16_F
".%"U16_F
".%"U16_F
" port %"U16_F
"\n", (void*)p
,
1525 ip4_addr1_16(addr
), ip4_addr2_16(addr
), ip4_addr3_16(addr
), ip4_addr4_16(addr
), port
));
1526 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("pbuf->len = %"U16_F
"\n", p
->len
));
1527 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("pbuf->tot_len = %"U16_F
"\n", p
->tot_len
));
1528 /* prevent warnings about unused arguments */
1529 LWIP_UNUSED_ARG(pcb
);
1530 LWIP_UNUSED_ARG(addr
);
1531 LWIP_UNUSED_ARG(port
);
1533 LWIP_ASSERT("reply wasn't freed", dhcp
->msg_in
== NULL
);
1535 if (p
->len
< DHCP_MIN_REPLY_LEN
) {
1536 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_WARNING
, ("DHCP reply message or pbuf too short\n"));
1537 goto free_pbuf_and_return
;
1540 if (reply_msg
->op
!= DHCP_BOOTREPLY
) {
1541 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_WARNING
, ("not a DHCP reply message, but type %"U16_F
"\n", (u16_t
)reply_msg
->op
));
1542 goto free_pbuf_and_return
;
1544 /* iterate through hardware address and match against DHCP message */
1545 for (i
= 0; i
< netif
->hwaddr_len
; i
++) {
1546 if (netif
->hwaddr
[i
] != reply_msg
->chaddr
[i
]) {
1547 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_WARNING
,
1548 ("netif->hwaddr[%"U16_F
"]==%02"X16_F
" != reply_msg->chaddr[%"U16_F
"]==%02"X16_F
"\n",
1549 (u16_t
)i
, (u16_t
)netif
->hwaddr
[i
], (u16_t
)i
, (u16_t
)reply_msg
->chaddr
[i
]));
1550 goto free_pbuf_and_return
;
1553 /* match transaction ID against what we expected */
1554 if (ntohl(reply_msg
->xid
) != dhcp
->xid
) {
1555 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_WARNING
,
1556 ("transaction id mismatch reply_msg->xid(%"X32_F
")!=dhcp->xid(%"X32_F
")\n",ntohl(reply_msg
->xid
),dhcp
->xid
));
1557 goto free_pbuf_and_return
;
1559 /* option fields could be unfold? */
1560 if (dhcp_parse_reply(dhcp
, p
) != ERR_OK
) {
1561 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
,
1562 ("problem unfolding DHCP message - too short on memory?\n"));
1563 goto free_pbuf_and_return
;
1566 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("searching DHCP_OPTION_MESSAGE_TYPE\n"));
1567 /* obtain pointer to DHCP message type */
1568 if (!dhcp_option_given(dhcp
, DHCP_OPTION_IDX_MSG_TYPE
)) {
1569 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_WARNING
, ("DHCP_OPTION_MESSAGE_TYPE option not found\n"));
1570 goto free_pbuf_and_return
;
1573 /* read DHCP message type */
1574 msg_type
= (u8_t
)dhcp_get_option_value(dhcp
, DHCP_OPTION_IDX_MSG_TYPE
);
1575 /* message type is DHCP ACK? */
1576 if (msg_type
== DHCP_ACK
) {
1577 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("DHCP_ACK received\n"));
1578 /* in requesting state? */
1579 if (dhcp
->state
== DHCP_REQUESTING
) {
1580 dhcp_handle_ack(netif
);
1581 #if DHCP_DOES_ARP_CHECK
1582 /* check if the acknowledged lease address is already in use */
1585 /* bind interface to the acknowledged lease address */
1589 /* already bound to the given lease address? */
1590 else if ((dhcp
->state
== DHCP_REBOOTING
) || (dhcp
->state
== DHCP_REBINDING
) || (dhcp
->state
== DHCP_RENEWING
)) {
1594 /* received a DHCP_NAK in appropriate state? */
1595 else if ((msg_type
== DHCP_NAK
) &&
1596 ((dhcp
->state
== DHCP_REBOOTING
) || (dhcp
->state
== DHCP_REQUESTING
) ||
1597 (dhcp
->state
== DHCP_REBINDING
) || (dhcp
->state
== DHCP_RENEWING
))) {
1598 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("DHCP_NAK received\n"));
1599 dhcp_handle_nak(netif
);
1601 /* received a DHCP_OFFER in DHCP_SELECTING state? */
1602 else if ((msg_type
== DHCP_OFFER
) && (dhcp
->state
== DHCP_SELECTING
)) {
1603 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
, ("DHCP_OFFER received in DHCP_SELECTING state\n"));
1604 dhcp
->request_timeout
= 0;
1605 /* remember offered lease */
1606 dhcp_handle_offer(netif
);
1608 free_pbuf_and_return
:
1609 dhcp
->msg_in
= NULL
;
1614 * Create a DHCP request, fill in common headers
1616 * @param netif the netif under DHCP control
1617 * @param dhcp dhcp control struct
1618 * @param message_type message type of the request
1621 dhcp_create_msg(struct netif
*netif
, struct dhcp
*dhcp
, u8_t message_type
)
1624 #ifndef DHCP_GLOBAL_XID
1625 /** default global transaction identifier starting value (easy to match
1626 * with a packet analyser). We simply increment for each new request.
1627 * Predefine DHCP_GLOBAL_XID to a better value or a function call to generate one
1628 * at runtime, any supporting function prototypes can be defined in DHCP_GLOBAL_XID_HEADER */
1629 static u32_t xid
= 0xABCD0000;
1632 static u8_t xid_initialised
= 0;
1633 if (!xid_initialised
) {
1634 xid
= DHCP_GLOBAL_XID
;
1635 xid_initialised
= !xid_initialised
;
1638 LWIP_ERROR("dhcp_create_msg: netif != NULL", (netif
!= NULL
), return ERR_ARG
;);
1639 LWIP_ERROR("dhcp_create_msg: dhcp != NULL", (dhcp
!= NULL
), return ERR_VAL
;);
1640 LWIP_ASSERT("dhcp_create_msg: dhcp->p_out == NULL", dhcp
->p_out
== NULL
);
1641 LWIP_ASSERT("dhcp_create_msg: dhcp->msg_out == NULL", dhcp
->msg_out
== NULL
);
1642 dhcp
->p_out
= pbuf_alloc(PBUF_TRANSPORT
, sizeof(struct dhcp_msg
), PBUF_RAM
);
1643 if (dhcp
->p_out
== NULL
) {
1644 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
| LWIP_DBG_LEVEL_SERIOUS
,
1645 ("dhcp_create_msg(): could not allocate pbuf\n"));
1648 LWIP_ASSERT("dhcp_create_msg: check that first pbuf can hold struct dhcp_msg",
1649 (dhcp
->p_out
->len
>= sizeof(struct dhcp_msg
)));
1651 /* reuse transaction identifier in retransmissions */
1652 if (dhcp
->tries
== 0) {
1656 LWIP_DEBUGF(DHCP_DEBUG
| LWIP_DBG_TRACE
,
1657 ("transaction id xid(%"X32_F
")\n", xid
));
1659 dhcp
->msg_out
= (struct dhcp_msg
*)dhcp
->p_out
->payload
;
1661 dhcp
->msg_out
->op
= DHCP_BOOTREQUEST
;
1662 /* TODO: make link layer independent */
1663 dhcp
->msg_out
->htype
= DHCP_HTYPE_ETH
;
1664 dhcp
->msg_out
->hlen
= netif
->hwaddr_len
;
1665 dhcp
->msg_out
->hops
= 0;
1666 dhcp
->msg_out
->xid
= htonl(dhcp
->xid
);
1667 dhcp
->msg_out
->secs
= 0;
1668 /* we don't need the broadcast flag since we can receive unicast traffic
1669 before being fully configured! */
1670 dhcp
->msg_out
->flags
= 0;
1671 ip_addr_set_zero(&dhcp
->msg_out
->ciaddr
);
1672 /* set ciaddr to netif->ip_addr based on message_type and state */
1673 if ((message_type
== DHCP_INFORM
) || (message_type
== DHCP_DECLINE
) ||
1674 ((message_type
== DHCP_REQUEST
) && /* DHCP_BOUND not used for sending! */
1675 ((dhcp
->state
==DHCP_RENEWING
) || dhcp
->state
==DHCP_REBINDING
))) {
1676 ip_addr_copy(dhcp
->msg_out
->ciaddr
, netif
->ip_addr
);
1678 ip_addr_set_zero(&dhcp
->msg_out
->yiaddr
);
1679 ip_addr_set_zero(&dhcp
->msg_out
->siaddr
);
1680 ip_addr_set_zero(&dhcp
->msg_out
->giaddr
);
1681 for (i
= 0; i
< DHCP_CHADDR_LEN
; i
++) {
1682 /* copy netif hardware address, pad with zeroes */
1683 dhcp
->msg_out
->chaddr
[i
] = (i
< netif
->hwaddr_len
) ? netif
->hwaddr
[i
] : 0/* pad byte*/;
1685 for (i
= 0; i
< DHCP_SNAME_LEN
; i
++) {
1686 dhcp
->msg_out
->sname
[i
] = 0;
1688 for (i
= 0; i
< DHCP_FILE_LEN
; i
++) {
1689 dhcp
->msg_out
->file
[i
] = 0;
1691 dhcp
->msg_out
->cookie
= PP_HTONL(DHCP_MAGIC_COOKIE
);
1692 dhcp
->options_out_len
= 0;
1693 /* fill options field with an incrementing array (for debugging purposes) */
1694 for (i
= 0; i
< DHCP_OPTIONS_LEN
; i
++) {
1695 dhcp
->msg_out
->options
[i
] = (u8_t
)i
; /* for debugging only, no matter if truncated */
1697 /* Add option MESSAGE_TYPE */
1698 dhcp_option(dhcp
, DHCP_OPTION_MESSAGE_TYPE
, DHCP_OPTION_MESSAGE_TYPE_LEN
);
1699 dhcp_option_byte(dhcp
, message_type
);
1704 * Free previously allocated memory used to send a DHCP request.
1706 * @param dhcp the dhcp struct to free the request from
1709 dhcp_delete_msg(struct dhcp
*dhcp
)
1711 LWIP_ERROR("dhcp_delete_msg: dhcp != NULL", (dhcp
!= NULL
), return;);
1712 LWIP_ASSERT("dhcp_delete_msg: dhcp->p_out != NULL", dhcp
->p_out
!= NULL
);
1713 LWIP_ASSERT("dhcp_delete_msg: dhcp->msg_out != NULL", dhcp
->msg_out
!= NULL
);
1714 if (dhcp
->p_out
!= NULL
) {
1715 pbuf_free(dhcp
->p_out
);
1718 dhcp
->msg_out
= NULL
;
1722 * Add a DHCP message trailer
1724 * Adds the END option to the DHCP message, and if
1725 * necessary, up to three padding bytes.
1727 * @param dhcp DHCP state structure
1730 dhcp_option_trailer(struct dhcp
*dhcp
)
1732 LWIP_ERROR("dhcp_option_trailer: dhcp != NULL", (dhcp
!= NULL
), return;);
1733 LWIP_ASSERT("dhcp_option_trailer: dhcp->msg_out != NULL\n", dhcp
->msg_out
!= NULL
);
1734 LWIP_ASSERT("dhcp_option_trailer: dhcp->options_out_len < DHCP_OPTIONS_LEN\n", dhcp
->options_out_len
< DHCP_OPTIONS_LEN
);
1735 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = DHCP_OPTION_END
;
1736 /* packet is too small, or not 4 byte aligned? */
1737 while ((dhcp
->options_out_len
< DHCP_MIN_OPTIONS_LEN
) || (dhcp
->options_out_len
& 3)) {
1738 /* LWIP_DEBUGF(DHCP_DEBUG,("dhcp_option_trailer:dhcp->options_out_len=%"U16_F", DHCP_OPTIONS_LEN=%"U16_F, dhcp->options_out_len, DHCP_OPTIONS_LEN)); */
1739 LWIP_ASSERT("dhcp_option_trailer: dhcp->options_out_len < DHCP_OPTIONS_LEN\n", dhcp
->options_out_len
< DHCP_OPTIONS_LEN
);
1740 /* add a fill/padding byte */
1741 dhcp
->msg_out
->options
[dhcp
->options_out_len
++] = 0;
1745 #endif /* LWIP_DHCP */