/** | |
* @file | |
* Dynamic Host Configuration Protocol client | |
* | |
*/ | |
/* | |
* | |
* Copyright (c) 2001-2004 Leon Woestenberg <leon.woestenberg@gmx.net> | |
* Copyright (c) 2001-2004 Axon Digital Design B.V., The Netherlands. | |
* All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without modification, | |
* are permitted provided that the following conditions are met: | |
* | |
* 1. Redistributions of source code must retain the above copyright notice, | |
* this list of conditions and the following disclaimer. | |
* 2. Redistributions in binary form must reproduce the above copyright notice, | |
* this list of conditions and the following disclaimer in the documentation | |
* and/or other materials provided with the distribution. | |
* 3. The name of the author may not be used to endorse or promote products | |
* derived from this software without specific prior written permission. | |
* | |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED | |
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT | |
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT | |
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING | |
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY | |
* OF SUCH DAMAGE. | |
* | |
* This file is a contribution to the lwIP TCP/IP stack. | |
* The Swedish Institute of Computer Science and Adam Dunkels | |
* are specifically granted permission to redistribute this | |
* source code. | |
* | |
* Author: Leon Woestenberg <leon.woestenberg@gmx.net> | |
* | |
* This is a DHCP client for the lwIP TCP/IP stack. It aims to conform | |
* with RFC 2131 and RFC 2132. | |
* | |
* TODO: | |
* - Proper parsing of DHCP messages exploiting file/sname field overloading. | |
* - Add JavaDoc style documentation (API, internals). | |
* - Support for interfaces other than Ethernet (SLIP, PPP, ...) | |
* | |
* Please coordinate changes and requests with Leon Woestenberg | |
* <leon.woestenberg@gmx.net> | |
* | |
* Integration with your code: | |
* | |
* In lwip/dhcp.h | |
* #define DHCP_COARSE_TIMER_SECS (recommended 60 which is a minute) | |
* #define DHCP_FINE_TIMER_MSECS (recommended 500 which equals TCP coarse timer) | |
* | |
* Then have your application call dhcp_coarse_tmr() and | |
* dhcp_fine_tmr() on the defined intervals. | |
* | |
* dhcp_start(struct netif *netif); | |
* starts a DHCP client instance which configures the interface by | |
* obtaining an IP address lease and maintaining it. | |
* | |
* Use dhcp_release(netif) to end the lease and use dhcp_stop(netif) | |
* to remove the DHCP client. | |
* | |
*/ | |
#include "lwip/opt.h" | |
#if LWIP_DHCP /* don't build if not configured for use in lwipopts.h */ | |
#include "lwip/stats.h" | |
#include "lwip/mem.h" | |
#include "lwip/udp.h" | |
#include "lwip/ip_addr.h" | |
#include "lwip/netif.h" | |
#include "lwip/inet.h" | |
#include "lwip/sys.h" | |
#include "lwip/dhcp.h" | |
#include "lwip/autoip.h" | |
#include "lwip/dns.h" | |
#include "netif/etharp.h" | |
#include <string.h> | |
/** global transaction identifier, must be | |
* unique for each DHCP request. We simply increment, starting | |
* with this value (easy to match with a packet analyzer) */ | |
static u32_t xid = 0xABCD0000; | |
/* DHCP client state machine functions */ | |
static void dhcp_handle_ack(struct netif *netif); | |
static void dhcp_handle_nak(struct netif *netif); | |
static void dhcp_handle_offer(struct netif *netif); | |
static err_t dhcp_discover(struct netif *netif); | |
static err_t dhcp_select(struct netif *netif); | |
static void dhcp_check(struct netif *netif); | |
static void dhcp_bind(struct netif *netif); | |
#if DHCP_DOES_ARP_CHECK | |
static err_t dhcp_decline(struct netif *netif); | |
#endif /* DHCP_DOES_ARP_CHECK */ | |
static err_t dhcp_rebind(struct netif *netif); | |
static void dhcp_set_state(struct dhcp *dhcp, u8_t new_state); | |
/* receive, unfold, parse and free incoming messages */ | |
static void dhcp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port); | |
static err_t dhcp_unfold_reply(struct dhcp *dhcp); | |
static u8_t *dhcp_get_option_ptr(struct dhcp *dhcp, u8_t option_type); | |
static u8_t dhcp_get_option_byte(u8_t *ptr); | |
#if 0 | |
static u16_t dhcp_get_option_short(u8_t *ptr); | |
#endif | |
static u32_t dhcp_get_option_long(u8_t *ptr); | |
static void dhcp_free_reply(struct dhcp *dhcp); | |
/* set the DHCP timers */ | |
static void dhcp_timeout(struct netif *netif); | |
static void dhcp_t1_timeout(struct netif *netif); | |
static void dhcp_t2_timeout(struct netif *netif); | |
/* build outgoing messages */ | |
/* create a DHCP request, fill in common headers */ | |
static err_t dhcp_create_request(struct netif *netif); | |
/* free a DHCP request */ | |
static void dhcp_delete_request(struct netif *netif); | |
/* add a DHCP option (type, then length in bytes) */ | |
static void dhcp_option(struct dhcp *dhcp, u8_t option_type, u8_t option_len); | |
/* add option values */ | |
static void dhcp_option_byte(struct dhcp *dhcp, u8_t value); | |
static void dhcp_option_short(struct dhcp *dhcp, u16_t value); | |
static void dhcp_option_long(struct dhcp *dhcp, u32_t value); | |
/* always add the DHCP options trailer to end and pad */ | |
static void dhcp_option_trailer(struct dhcp *dhcp); | |
/** | |
* Back-off the DHCP client (because of a received NAK response). | |
* | |
* Back-off the DHCP client because of a received NAK. Receiving a | |
* NAK means the client asked for something non-sensible, for | |
* example when it tries to renew a lease obtained on another network. | |
* | |
* We clear any existing set IP address and restart DHCP negotiation | |
* afresh (as per RFC2131 3.2.3). | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static void | |
dhcp_handle_nak(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_handle_nak(netif=%p) %c%c%"U16_F"\n", | |
(void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num)); | |
/* Set the interface down since the address must no longer be used, as per RFC2131 */ | |
netif_set_down(netif); | |
/* remove IP address from interface */ | |
netif_set_ipaddr(netif, IP_ADDR_ANY); | |
netif_set_gw(netif, IP_ADDR_ANY); | |
netif_set_netmask(netif, IP_ADDR_ANY); | |
/* Change to a defined state */ | |
dhcp_set_state(dhcp, DHCP_BACKING_OFF); | |
/* We can immediately restart discovery */ | |
dhcp_discover(netif); | |
} | |
/** | |
* Checks if the offered IP address is already in use. | |
* | |
* It does so by sending an ARP request for the offered address and | |
* entering CHECKING state. If no ARP reply is received within a small | |
* interval, the address is assumed to be free for use by us. | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static void | |
dhcp_check(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
err_t result; | |
u16_t msecs; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_check(netif=%p) %c%c\n", (void *)netif, (s16_t)netif->name[0], | |
(s16_t)netif->name[1])); | |
/* create an ARP query for the offered IP address, expecting that no host | |
responds, as the IP address should not be in use. */ | |
result = etharp_query(netif, &dhcp->offered_ip_addr, NULL); | |
if (result != ERR_OK) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_check: could not perform ARP query\n")); | |
} | |
dhcp->tries++; | |
msecs = 500; | |
dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_check(): set request timeout %"U16_F" msecs\n", msecs)); | |
dhcp_set_state(dhcp, DHCP_CHECKING); | |
} | |
/** | |
* Remember the configuration offered by a DHCP server. | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static void | |
dhcp_handle_offer(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
/* obtain the server address */ | |
u8_t *option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_SERVER_ID); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_handle_offer(netif=%p) %c%c%"U16_F"\n", | |
(void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num)); | |
if (option_ptr != NULL) { | |
dhcp->server_ip_addr.addr = htonl(dhcp_get_option_long(&option_ptr[2])); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_handle_offer(): server 0x%08"X32_F"\n", dhcp->server_ip_addr.addr)); | |
/* remember offered address */ | |
ip_addr_set(&dhcp->offered_ip_addr, (struct ip_addr *)&dhcp->msg_in->yiaddr); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_handle_offer(): offer for 0x%08"X32_F"\n", dhcp->offered_ip_addr.addr)); | |
dhcp_select(netif); | |
} | |
} | |
/** | |
* Select a DHCP server offer out of all offers. | |
* | |
* Simply select the first offer received. | |
* | |
* @param netif the netif under DHCP control | |
* @return lwIP specific error (see error.h) | |
*/ | |
static err_t | |
dhcp_select(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
err_t result; | |
u16_t msecs; | |
#if LWIP_NETIF_HOSTNAME | |
const char *p; | |
#endif /* LWIP_NETIF_HOSTNAME */ | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_select(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num)); | |
/* create and initialize the DHCP message header */ | |
result = dhcp_create_request(netif); | |
if (result == ERR_OK) { | |
dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN); | |
dhcp_option_byte(dhcp, DHCP_REQUEST); | |
dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN); | |
dhcp_option_short(dhcp, 576); | |
/* MUST request the offered IP address */ | |
dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4); | |
dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr)); | |
dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4); | |
dhcp_option_long(dhcp, ntohl(dhcp->server_ip_addr.addr)); | |
dhcp_option(dhcp, DHCP_OPTION_PARAMETER_REQUEST_LIST, 4/*num options*/); | |
dhcp_option_byte(dhcp, DHCP_OPTION_SUBNET_MASK); | |
dhcp_option_byte(dhcp, DHCP_OPTION_ROUTER); | |
dhcp_option_byte(dhcp, DHCP_OPTION_BROADCAST); | |
dhcp_option_byte(dhcp, DHCP_OPTION_DNS_SERVER); | |
#if LWIP_NETIF_HOSTNAME | |
p = (const char*)netif->hostname; | |
if (p!=NULL) { | |
dhcp_option(dhcp, DHCP_OPTION_HOSTNAME, strlen(p)); | |
while (*p) { | |
dhcp_option_byte(dhcp, *p++); | |
} | |
} | |
#endif /* LWIP_NETIF_HOSTNAME */ | |
dhcp_option_trailer(dhcp); | |
/* shrink the pbuf to the actual content length */ | |
pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len); | |
/* TODO: we really should bind to a specific local interface here | |
but we cannot specify an unconfigured netif as it is addressless */ | |
/* send broadcast to any DHCP server */ | |
udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif); | |
/* reconnect to any (or to server here?!) */ | |
udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT); | |
dhcp_delete_request(netif); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_select: REQUESTING\n")); | |
dhcp_set_state(dhcp, DHCP_REQUESTING); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_select: could not allocate DHCP request\n")); | |
} | |
dhcp->tries++; | |
msecs = dhcp->tries < 4 ? dhcp->tries * 1000 : 4 * 1000; | |
dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_select(): set request timeout %"U16_F" msecs\n", msecs)); | |
return result; | |
} | |
/** | |
* The DHCP timer that checks for lease renewal/rebind timeouts. | |
* | |
*/ | |
void | |
dhcp_coarse_tmr() | |
{ | |
struct netif *netif = netif_list; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_coarse_tmr()\n")); | |
/* iterate through all network interfaces */ | |
while (netif != NULL) { | |
/* only act on DHCP configured interfaces */ | |
if (netif->dhcp != NULL) { | |
/* timer is active (non zero), and triggers (zeroes) now? */ | |
if (netif->dhcp->t2_timeout-- == 1) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_coarse_tmr(): t2 timeout\n")); | |
/* this clients' rebind timeout triggered */ | |
dhcp_t2_timeout(netif); | |
/* timer is active (non zero), and triggers (zeroes) now */ | |
} else if (netif->dhcp->t1_timeout-- == 1) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_coarse_tmr(): t1 timeout\n")); | |
/* this clients' renewal timeout triggered */ | |
dhcp_t1_timeout(netif); | |
} | |
} | |
/* proceed to next netif */ | |
netif = netif->next; | |
} | |
} | |
/** | |
* DHCP transaction timeout handling | |
* | |
* A DHCP server is expected to respond within a short period of time. | |
* This timer checks whether an outstanding DHCP request is timed out. | |
* | |
*/ | |
void | |
dhcp_fine_tmr() | |
{ | |
struct netif *netif = netif_list; | |
/* loop through netif's */ | |
while (netif != NULL) { | |
/* only act on DHCP configured interfaces */ | |
if (netif->dhcp != NULL) { | |
/* timer is active (non zero), and is about to trigger now */ | |
if (netif->dhcp->request_timeout > 1) { | |
netif->dhcp->request_timeout--; | |
} | |
else if (netif->dhcp->request_timeout == 1) { | |
netif->dhcp->request_timeout--; | |
/* { netif->dhcp->request_timeout == 0 } */ | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_fine_tmr(): request timeout\n")); | |
/* this clients' request timeout triggered */ | |
dhcp_timeout(netif); | |
} | |
} | |
/* proceed to next network interface */ | |
netif = netif->next; | |
} | |
} | |
/** | |
* A DHCP negotiation transaction, or ARP request, has timed out. | |
* | |
* The timer that was started with the DHCP or ARP request has | |
* timed out, indicating no response was received in time. | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static void | |
dhcp_timeout(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_timeout()\n")); | |
/* back-off period has passed, or server selection timed out */ | |
if ((dhcp->state == DHCP_BACKING_OFF) || (dhcp->state == DHCP_SELECTING)) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_timeout(): restarting discovery\n")); | |
dhcp_discover(netif); | |
/* receiving the requested lease timed out */ | |
} else if (dhcp->state == DHCP_REQUESTING) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): REQUESTING, DHCP request timed out\n")); | |
if (dhcp->tries <= 5) { | |
dhcp_select(netif); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): REQUESTING, releasing, restarting\n")); | |
dhcp_release(netif); | |
dhcp_discover(netif); | |
} | |
/* received no ARP reply for the offered address (which is good) */ | |
} else if (dhcp->state == DHCP_CHECKING) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): CHECKING, ARP request timed out\n")); | |
if (dhcp->tries <= 1) { | |
dhcp_check(netif); | |
/* no ARP replies on the offered address, | |
looks like the IP address is indeed free */ | |
} else { | |
/* bind the interface to the offered address */ | |
dhcp_bind(netif); | |
} | |
} | |
/* did not get response to renew request? */ | |
else if (dhcp->state == DHCP_RENEWING) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): RENEWING, DHCP request timed out\n")); | |
/* just retry renewal */ | |
/* note that the rebind timer will eventually time-out if renew does not work */ | |
dhcp_renew(netif); | |
/* did not get response to rebind request? */ | |
} else if (dhcp->state == DHCP_REBINDING) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): REBINDING, DHCP request timed out\n")); | |
if (dhcp->tries <= 8) { | |
dhcp_rebind(netif); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_timeout(): RELEASING, DISCOVERING\n")); | |
dhcp_release(netif); | |
dhcp_discover(netif); | |
} | |
} | |
} | |
/** | |
* The renewal period has timed out. | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static void | |
dhcp_t1_timeout(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_t1_timeout()\n")); | |
if ((dhcp->state == DHCP_REQUESTING) || (dhcp->state == DHCP_BOUND) || (dhcp->state == DHCP_RENEWING)) { | |
/* just retry to renew - note that the rebind timer (t2) will | |
* eventually time-out if renew tries fail. */ | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_t1_timeout(): must renew\n")); | |
dhcp_renew(netif); | |
} | |
} | |
/** | |
* The rebind period has timed out. | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static void | |
dhcp_t2_timeout(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_t2_timeout()\n")); | |
if ((dhcp->state == DHCP_REQUESTING) || (dhcp->state == DHCP_BOUND) || (dhcp->state == DHCP_RENEWING)) { | |
/* just retry to rebind */ | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_t2_timeout(): must rebind\n")); | |
dhcp_rebind(netif); | |
} | |
} | |
/** | |
* Handle a DHCP ACK packet | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static void | |
dhcp_handle_ack(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
u8_t *option_ptr; | |
/* clear options we might not get from the ACK */ | |
dhcp->offered_sn_mask.addr = 0; | |
dhcp->offered_gw_addr.addr = 0; | |
dhcp->offered_bc_addr.addr = 0; | |
/* lease time given? */ | |
option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_LEASE_TIME); | |
if (option_ptr != NULL) { | |
/* remember offered lease time */ | |
dhcp->offered_t0_lease = dhcp_get_option_long(option_ptr + 2); | |
} | |
/* renewal period given? */ | |
option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_T1); | |
if (option_ptr != NULL) { | |
/* remember given renewal period */ | |
dhcp->offered_t1_renew = dhcp_get_option_long(option_ptr + 2); | |
} else { | |
/* calculate safe periods for renewal */ | |
dhcp->offered_t1_renew = dhcp->offered_t0_lease / 2; | |
} | |
/* renewal period given? */ | |
option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_T2); | |
if (option_ptr != NULL) { | |
/* remember given rebind period */ | |
dhcp->offered_t2_rebind = dhcp_get_option_long(option_ptr + 2); | |
} else { | |
/* calculate safe periods for rebinding */ | |
dhcp->offered_t2_rebind = dhcp->offered_t0_lease; | |
} | |
/* (y)our internet address */ | |
ip_addr_set(&dhcp->offered_ip_addr, &dhcp->msg_in->yiaddr); | |
/** | |
* Patch #1308 | |
* TODO: we must check if the file field is not overloaded by DHCP options! | |
*/ | |
#if 0 | |
/* boot server address */ | |
ip_addr_set(&dhcp->offered_si_addr, &dhcp->msg_in->siaddr); | |
/* boot file name */ | |
if (dhcp->msg_in->file[0]) { | |
dhcp->boot_file_name = mem_malloc(strlen(dhcp->msg_in->file) + 1); | |
strcpy(dhcp->boot_file_name, dhcp->msg_in->file); | |
} | |
#endif | |
/* subnet mask */ | |
option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_SUBNET_MASK); | |
/* subnet mask given? */ | |
if (option_ptr != NULL) { | |
dhcp->offered_sn_mask.addr = htonl(dhcp_get_option_long(&option_ptr[2])); | |
} | |
/* gateway router */ | |
option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_ROUTER); | |
if (option_ptr != NULL) { | |
dhcp->offered_gw_addr.addr = htonl(dhcp_get_option_long(&option_ptr[2])); | |
} | |
/* broadcast address */ | |
option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_BROADCAST); | |
if (option_ptr != NULL) { | |
dhcp->offered_bc_addr.addr = htonl(dhcp_get_option_long(&option_ptr[2])); | |
} | |
/* DNS servers */ | |
option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_DNS_SERVER); | |
if (option_ptr != NULL) { | |
u8_t n; | |
dhcp->dns_count = dhcp_get_option_byte(&option_ptr[1]) / (u32_t)sizeof(struct ip_addr); | |
/* limit to at most DHCP_MAX_DNS DNS servers */ | |
if (dhcp->dns_count > DHCP_MAX_DNS) | |
dhcp->dns_count = DHCP_MAX_DNS; | |
for (n = 0; n < dhcp->dns_count; n++) { | |
dhcp->offered_dns_addr[n].addr = htonl(dhcp_get_option_long(&option_ptr[2 + n * 4])); | |
#if LWIP_DNS | |
dns_setserver( n, (struct ip_addr *)(&(dhcp->offered_dns_addr[n].addr))); | |
#endif /* LWIP_DNS */ | |
} | |
#if LWIP_DNS | |
dns_setserver( n, (struct ip_addr *)(&ip_addr_any)); | |
#endif /* LWIP_DNS */ | |
} | |
} | |
/** | |
* Start DHCP negotiation for a network interface. | |
* | |
* If no DHCP client instance was attached to this interface, | |
* a new client is created first. If a DHCP client instance | |
* was already present, it restarts negotiation. | |
* | |
* @param netif The lwIP network interface | |
* @return lwIP error code | |
* - ERR_OK - No error | |
* - ERR_MEM - Out of memory | |
*/ | |
err_t | |
dhcp_start(struct netif *netif) | |
{ | |
struct dhcp *dhcp; | |
err_t result = ERR_OK; | |
LWIP_ERROR("netif != NULL", (netif != NULL), return ERR_ARG;); | |
dhcp = netif->dhcp; | |
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)); | |
netif->flags &= ~NETIF_FLAG_DHCP; | |
/* no DHCP client attached yet? */ | |
if (dhcp == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): starting new DHCP client\n")); | |
dhcp = mem_malloc(sizeof(struct dhcp)); | |
if (dhcp == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): could not allocate dhcp\n")); | |
return ERR_MEM; | |
} | |
/* store this dhcp client in the netif */ | |
netif->dhcp = dhcp; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): allocated dhcp")); | |
/* already has DHCP client attached */ | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | 3, ("dhcp_start(): restarting DHCP configuration\n")); | |
} | |
/* clear data structure */ | |
memset(dhcp, 0, sizeof(struct dhcp)); | |
/* allocate UDP PCB */ | |
dhcp->pcb = udp_new(); | |
if (dhcp->pcb == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): could not obtain pcb\n")); | |
mem_free((void *)dhcp); | |
netif->dhcp = dhcp = NULL; | |
return ERR_MEM; | |
} | |
/* set up local and remote port for the pcb */ | |
udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT); | |
udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT); | |
/* set up the recv callback and argument */ | |
udp_recv(dhcp->pcb, dhcp_recv, netif); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): starting DHCP configuration\n")); | |
/* (re)start the DHCP negotiation */ | |
result = dhcp_discover(netif); | |
if (result != ERR_OK) { | |
/* free resources allocated above */ | |
dhcp_stop(netif); | |
return ERR_MEM; | |
} | |
netif->flags |= NETIF_FLAG_DHCP; | |
return result; | |
} | |
/** | |
* Inform a DHCP server of our manual configuration. | |
* | |
* This informs DHCP servers of our fixed IP address configuration | |
* by sending an INFORM message. It does not involve DHCP address | |
* configuration, it is just here to be nice to the network. | |
* | |
* @param netif The lwIP network interface | |
*/ | |
void | |
dhcp_inform(struct netif *netif) | |
{ | |
struct dhcp *dhcp, *old_dhcp = netif->dhcp; | |
err_t result = ERR_OK; | |
dhcp = mem_malloc(sizeof(struct dhcp)); | |
if (dhcp == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_inform(): could not allocate dhcp\n")); | |
return; | |
} | |
netif->dhcp = dhcp; | |
memset(dhcp, 0, sizeof(struct dhcp)); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_inform(): allocated dhcp\n")); | |
dhcp->pcb = udp_new(); | |
if (dhcp->pcb == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_inform(): could not obtain pcb")); | |
mem_free((void *)dhcp); | |
return; | |
} | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_inform(): created new udp pcb\n")); | |
/* create and initialize the DHCP message header */ | |
result = dhcp_create_request(netif); | |
if (result == ERR_OK) { | |
dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN); | |
dhcp_option_byte(dhcp, DHCP_INFORM); | |
dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN); | |
/* TODO: use netif->mtu ?! */ | |
dhcp_option_short(dhcp, 576); | |
dhcp_option_trailer(dhcp); | |
pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len); | |
udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT); | |
udp_connect(dhcp->pcb, IP_ADDR_BROADCAST, DHCP_SERVER_PORT); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_inform: INFORMING\n")); | |
udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif); | |
udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT); | |
dhcp_delete_request(netif); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_inform: could not allocate DHCP request\n")); | |
} | |
if (dhcp != NULL) { | |
if (dhcp->pcb != NULL) { | |
udp_remove(dhcp->pcb); | |
} | |
dhcp->pcb = NULL; | |
mem_free((void *)dhcp); | |
netif->dhcp = old_dhcp; | |
} | |
} | |
#if DHCP_DOES_ARP_CHECK | |
/** | |
* Match an ARP reply with the offered IP address. | |
* | |
* @param netif the network interface on which the reply was received | |
* @param addr The IP address we received a reply from | |
*/ | |
void dhcp_arp_reply(struct netif *netif, struct ip_addr *addr) | |
{ | |
LWIP_ERROR("netif != NULL", (netif != NULL), return;); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_arp_reply()\n")); | |
/* is a DHCP client doing an ARP check? */ | |
if ((netif->dhcp != NULL) && (netif->dhcp->state == DHCP_CHECKING)) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_arp_reply(): CHECKING, arp reply for 0x%08"X32_F"\n", addr->addr)); | |
/* did a host respond with the address we | |
were offered by the DHCP server? */ | |
if (ip_addr_cmp(addr, &netif->dhcp->offered_ip_addr)) { | |
/* we will not accept the offered address */ | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE | 1, ("dhcp_arp_reply(): arp reply matched with offered address, declining\n")); | |
dhcp_decline(netif); | |
} | |
} | |
} | |
/** | |
* Decline an offered lease. | |
* | |
* Tell the DHCP server we do not accept the offered address. | |
* One reason to decline the lease is when we find out the address | |
* is already in use by another host (through ARP). | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static err_t | |
dhcp_decline(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
err_t result = ERR_OK; | |
u16_t msecs; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_decline()\n")); | |
dhcp_set_state(dhcp, DHCP_BACKING_OFF); | |
/* create and initialize the DHCP message header */ | |
result = dhcp_create_request(netif); | |
if (result == ERR_OK) { | |
dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN); | |
dhcp_option_byte(dhcp, DHCP_DECLINE); | |
dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN); | |
dhcp_option_short(dhcp, 576); | |
dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4); | |
dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr)); | |
dhcp_option_trailer(dhcp); | |
/* resize pbuf to reflect true size of options */ | |
pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len); | |
/* @todo: should we really connect here? we are performing sendto() */ | |
udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT); | |
/* per section 4.4.4, broadcast DECLINE messages */ | |
udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif); | |
dhcp_delete_request(netif); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_decline: BACKING OFF\n")); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_decline: could not allocate DHCP request\n")); | |
} | |
dhcp->tries++; | |
msecs = 10*1000; | |
dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_decline(): set request timeout %"U16_F" msecs\n", msecs)); | |
return result; | |
} | |
#endif | |
/** | |
* Start the DHCP process, discover a DHCP server. | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static err_t | |
dhcp_discover(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
err_t result = ERR_OK; | |
u16_t msecs; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_discover()\n")); | |
ip_addr_set(&dhcp->offered_ip_addr, IP_ADDR_ANY); | |
/* create and initialize the DHCP message header */ | |
result = dhcp_create_request(netif); | |
if (result == ERR_OK) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: making request\n")); | |
dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN); | |
dhcp_option_byte(dhcp, DHCP_DISCOVER); | |
dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN); | |
dhcp_option_short(dhcp, 576); | |
dhcp_option(dhcp, DHCP_OPTION_PARAMETER_REQUEST_LIST, 4/*num options*/); | |
dhcp_option_byte(dhcp, DHCP_OPTION_SUBNET_MASK); | |
dhcp_option_byte(dhcp, DHCP_OPTION_ROUTER); | |
dhcp_option_byte(dhcp, DHCP_OPTION_BROADCAST); | |
dhcp_option_byte(dhcp, DHCP_OPTION_DNS_SERVER); | |
dhcp_option_trailer(dhcp); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: realloc()ing\n")); | |
pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len); | |
udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: sendto(DISCOVER, IP_ADDR_BROADCAST, DHCP_SERVER_PORT)\n")); | |
udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_discover: deleting()ing\n")); | |
dhcp_delete_request(netif); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_discover: SELECTING\n")); | |
dhcp_set_state(dhcp, DHCP_SELECTING); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_discover: could not allocate DHCP request\n")); | |
} | |
dhcp->tries++; | |
#if LWIP_DHCP_AUTOIP_COOP | |
/* that means we waited 57 seconds */ | |
if(dhcp->tries >= 9 && dhcp->autoip_coop_state == DHCP_AUTOIP_COOP_STATE_OFF) { | |
dhcp->autoip_coop_state = DHCP_AUTOIP_COOP_STATE_ON; | |
autoip_start(netif); | |
} | |
#endif /* LWIP_DHCP_AUTOIP_COOP */ | |
msecs = dhcp->tries < 4 ? (dhcp->tries + 1) * 1000 : 10 * 1000; | |
dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_discover(): set request timeout %"U16_F" msecs\n", msecs)); | |
return result; | |
} | |
/** | |
* Bind the interface to the offered IP address. | |
* | |
* @param netif network interface to bind to the offered address | |
*/ | |
static void | |
dhcp_bind(struct netif *netif) | |
{ | |
u32_t timeout; | |
struct dhcp *dhcp; | |
struct ip_addr sn_mask, gw_addr; | |
LWIP_ERROR("dhcp_bind: netif != NULL", (netif != NULL), return;); | |
dhcp = netif->dhcp; | |
LWIP_ERROR("dhcp_bind: dhcp != NULL", (dhcp != NULL), return;); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_bind(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num)); | |
/* temporary DHCP lease? */ | |
if (dhcp->offered_t1_renew != 0xffffffffUL) { | |
/* set renewal period timer */ | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_bind(): t1 renewal timer %"U32_F" secs\n", dhcp->offered_t1_renew)); | |
timeout = (dhcp->offered_t1_renew + DHCP_COARSE_TIMER_SECS / 2) / DHCP_COARSE_TIMER_SECS; | |
if(timeout > 0xffff) { | |
timeout = 0xffff; | |
} | |
dhcp->t1_timeout = (u16_t)timeout; | |
if (dhcp->t1_timeout == 0) { | |
dhcp->t1_timeout = 1; | |
} | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_bind(): set request timeout %"U32_F" msecs\n", dhcp->offered_t1_renew*1000)); | |
} | |
/* set renewal period timer */ | |
if (dhcp->offered_t2_rebind != 0xffffffffUL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_bind(): t2 rebind timer %"U32_F" secs\n", dhcp->offered_t2_rebind)); | |
timeout = (dhcp->offered_t2_rebind + DHCP_COARSE_TIMER_SECS / 2) / DHCP_COARSE_TIMER_SECS; | |
if(timeout > 0xffff) { | |
timeout = 0xffff; | |
} | |
dhcp->t2_timeout = (u16_t)timeout; | |
if (dhcp->t2_timeout == 0) { | |
dhcp->t2_timeout = 1; | |
} | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_bind(): set request timeout %"U32_F" msecs\n", dhcp->offered_t2_rebind*1000)); | |
} | |
/* copy offered network mask */ | |
ip_addr_set(&sn_mask, &dhcp->offered_sn_mask); | |
/* subnet mask not given? */ | |
/* TODO: this is not a valid check. what if the network mask is 0? */ | |
if (sn_mask.addr == 0) { | |
/* choose a safe subnet mask given the network class */ | |
u8_t first_octet = ip4_addr1(&sn_mask); | |
if (first_octet <= 127) { | |
sn_mask.addr = htonl(0xff000000); | |
} else if (first_octet >= 192) { | |
sn_mask.addr = htonl(0xffffff00); | |
} else { | |
sn_mask.addr = htonl(0xffff0000); | |
} | |
} | |
ip_addr_set(&gw_addr, &dhcp->offered_gw_addr); | |
/* gateway address not given? */ | |
if (gw_addr.addr == 0) { | |
/* copy network address */ | |
gw_addr.addr = (dhcp->offered_ip_addr.addr & sn_mask.addr); | |
/* use first host address on network as gateway */ | |
gw_addr.addr |= htonl(0x00000001); | |
} | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_bind(): IP: 0x%08"X32_F"\n", dhcp->offered_ip_addr.addr)); | |
netif_set_ipaddr(netif, &dhcp->offered_ip_addr); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_bind(): SN: 0x%08"X32_F"\n", sn_mask.addr)); | |
netif_set_netmask(netif, &sn_mask); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_STATE, ("dhcp_bind(): GW: 0x%08"X32_F"\n", gw_addr.addr)); | |
netif_set_gw(netif, &gw_addr); | |
/* bring the interface up */ | |
netif_set_up(netif); | |
/* netif is now bound to DHCP leased address */ | |
dhcp_set_state(dhcp, DHCP_BOUND); | |
} | |
/** | |
* Renew an existing DHCP lease at the involved DHCP server. | |
* | |
* @param netif network interface which must renew its lease | |
*/ | |
err_t | |
dhcp_renew(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
err_t result; | |
u16_t msecs; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_renew()\n")); | |
dhcp_set_state(dhcp, DHCP_RENEWING); | |
/* create and initialize the DHCP message header */ | |
result = dhcp_create_request(netif); | |
if (result == ERR_OK) { | |
dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN); | |
dhcp_option_byte(dhcp, DHCP_REQUEST); | |
dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN); | |
/* TODO: use netif->mtu in some way */ | |
dhcp_option_short(dhcp, 576); | |
#if 0 | |
dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4); | |
dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr)); | |
#endif | |
#if 0 | |
dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4); | |
dhcp_option_long(dhcp, ntohl(dhcp->server_ip_addr.addr)); | |
#endif | |
/* append DHCP message trailer */ | |
dhcp_option_trailer(dhcp); | |
pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len); | |
udp_connect(dhcp->pcb, &dhcp->server_ip_addr, DHCP_SERVER_PORT); | |
udp_sendto_if(dhcp->pcb, dhcp->p_out, &dhcp->server_ip_addr, DHCP_SERVER_PORT, netif); | |
dhcp_delete_request(netif); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_renew: RENEWING\n")); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_renew: could not allocate DHCP request\n")); | |
} | |
dhcp->tries++; | |
/* back-off on retries, but to a maximum of 20 seconds */ | |
msecs = dhcp->tries < 10 ? dhcp->tries * 2000 : 20 * 1000; | |
dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_renew(): set request timeout %"U16_F" msecs\n", msecs)); | |
return result; | |
} | |
/** | |
* Rebind with a DHCP server for an existing DHCP lease. | |
* | |
* @param netif network interface which must rebind with a DHCP server | |
*/ | |
static err_t | |
dhcp_rebind(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
err_t result; | |
u16_t msecs; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_rebind()\n")); | |
dhcp_set_state(dhcp, DHCP_REBINDING); | |
/* create and initialize the DHCP message header */ | |
result = dhcp_create_request(netif); | |
if (result == ERR_OK) { | |
dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN); | |
dhcp_option_byte(dhcp, DHCP_REQUEST); | |
dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN); | |
dhcp_option_short(dhcp, 576); | |
#if 0 | |
dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4); | |
dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr)); | |
dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4); | |
dhcp_option_long(dhcp, ntohl(dhcp->server_ip_addr.addr)); | |
#endif | |
dhcp_option_trailer(dhcp); | |
pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len); | |
/* broadcast to server */ | |
udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT); | |
udp_sendto_if(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT, netif); | |
dhcp_delete_request(netif); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_rebind: REBINDING\n")); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_rebind: could not allocate DHCP request\n")); | |
} | |
dhcp->tries++; | |
msecs = dhcp->tries < 10 ? dhcp->tries * 1000 : 10 * 1000; | |
dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_rebind(): set request timeout %"U16_F" msecs\n", msecs)); | |
return result; | |
} | |
/** | |
* Release a DHCP lease. | |
* | |
* @param netif network interface which must release its lease | |
*/ | |
err_t | |
dhcp_release(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
err_t result; | |
u16_t msecs; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_release()\n")); | |
/* idle DHCP client */ | |
dhcp_set_state(dhcp, DHCP_OFF); | |
/* clean old DHCP offer */ | |
dhcp->server_ip_addr.addr = 0; | |
dhcp->offered_ip_addr.addr = dhcp->offered_sn_mask.addr = 0; | |
dhcp->offered_gw_addr.addr = dhcp->offered_bc_addr.addr = 0; | |
dhcp->offered_t0_lease = dhcp->offered_t1_renew = dhcp->offered_t2_rebind = 0; | |
dhcp->dns_count = 0; | |
/* create and initialize the DHCP message header */ | |
result = dhcp_create_request(netif); | |
if (result == ERR_OK) { | |
dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN); | |
dhcp_option_byte(dhcp, DHCP_RELEASE); | |
dhcp_option_trailer(dhcp); | |
pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len); | |
udp_connect(dhcp->pcb, &dhcp->server_ip_addr, DHCP_SERVER_PORT); | |
udp_sendto_if(dhcp->pcb, dhcp->p_out, &dhcp->server_ip_addr, DHCP_SERVER_PORT, netif); | |
dhcp_delete_request(netif); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_release: RELEASED, DHCP_OFF\n")); | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_release: could not allocate DHCP request\n")); | |
} | |
dhcp->tries++; | |
msecs = dhcp->tries < 10 ? dhcp->tries * 1000 : 10 * 1000; | |
dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_STATE, ("dhcp_release(): set request timeout %"U16_F" msecs\n", msecs)); | |
/* bring the interface down */ | |
netif_set_down(netif); | |
/* remove IP address from interface */ | |
netif_set_ipaddr(netif, IP_ADDR_ANY); | |
netif_set_gw(netif, IP_ADDR_ANY); | |
netif_set_netmask(netif, IP_ADDR_ANY); | |
/* TODO: netif_down(netif); */ | |
return result; | |
} | |
/** | |
* Remove the DHCP client from the interface. | |
* | |
* @param netif The network interface to stop DHCP on | |
*/ | |
void | |
dhcp_stop(struct netif *netif) | |
{ | |
struct dhcp *dhcp = netif->dhcp; | |
LWIP_ERROR("dhcp_stop: netif != NULL", (netif != NULL), return;); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_stop()\n")); | |
/* netif is DHCP configured? */ | |
if (dhcp != NULL) { | |
if (dhcp->pcb != NULL) { | |
udp_remove(dhcp->pcb); | |
dhcp->pcb = NULL; | |
} | |
if (dhcp->p != NULL) { | |
pbuf_free(dhcp->p); | |
dhcp->p = NULL; | |
} | |
/* free unfolded reply */ | |
dhcp_free_reply(dhcp); | |
mem_free((void *)dhcp); | |
netif->dhcp = NULL; | |
} | |
} | |
/* | |
* Set the DHCP state of a DHCP client. | |
* | |
* If the state changed, reset the number of tries. | |
* | |
* TODO: we might also want to reset the timeout here? | |
*/ | |
static void | |
dhcp_set_state(struct dhcp *dhcp, u8_t new_state) | |
{ | |
if (new_state != dhcp->state) { | |
dhcp->state = new_state; | |
dhcp->tries = 0; | |
} | |
} | |
/* | |
* Concatenate an option type and length field to the outgoing | |
* DHCP message. | |
* | |
*/ | |
static void | |
dhcp_option(struct dhcp *dhcp, u8_t option_type, u8_t option_len) | |
{ | |
LWIP_ASSERT("dhcp_option: dhcp->options_out_len + 2 + option_len <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 2U + option_len <= DHCP_OPTIONS_LEN); | |
dhcp->msg_out->options[dhcp->options_out_len++] = option_type; | |
dhcp->msg_out->options[dhcp->options_out_len++] = option_len; | |
} | |
/* | |
* Concatenate a single byte to the outgoing DHCP message. | |
* | |
*/ | |
static void | |
dhcp_option_byte(struct dhcp *dhcp, u8_t value) | |
{ | |
LWIP_ASSERT("dhcp_option_byte: dhcp->options_out_len < DHCP_OPTIONS_LEN", dhcp->options_out_len < DHCP_OPTIONS_LEN); | |
dhcp->msg_out->options[dhcp->options_out_len++] = value; | |
} | |
static void | |
dhcp_option_short(struct dhcp *dhcp, u16_t value) | |
{ | |
LWIP_ASSERT("dhcp_option_short: dhcp->options_out_len + 2 <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 2U <= DHCP_OPTIONS_LEN); | |
dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0xff00U) >> 8); | |
dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t) (value & 0x00ffU); | |
} | |
static void | |
dhcp_option_long(struct dhcp *dhcp, u32_t value) | |
{ | |
LWIP_ASSERT("dhcp_option_long: dhcp->options_out_len + 4 <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 4U <= DHCP_OPTIONS_LEN); | |
dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0xff000000UL) >> 24); | |
dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0x00ff0000UL) >> 16); | |
dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0x0000ff00UL) >> 8); | |
dhcp->msg_out->options[dhcp->options_out_len++] = (u8_t)((value & 0x000000ffUL)); | |
} | |
/** | |
* Extract the DHCP message and the DHCP options. | |
* | |
* Extract the DHCP message and the DHCP options, each into a contiguous | |
* piece of memory. As a DHCP message is variable sized by its options, | |
* and also allows overriding some fields for options, the easy approach | |
* is to first unfold the options into a conitguous piece of memory, and | |
* use that further on. | |
* | |
*/ | |
static err_t | |
dhcp_unfold_reply(struct dhcp *dhcp) | |
{ | |
u16_t ret; | |
LWIP_ERROR("dhcp != NULL", (dhcp != NULL), return ERR_ARG;); | |
LWIP_ERROR("dhcp->p != NULL", (dhcp->p != NULL), return ERR_VAL;); | |
/* free any left-overs from previous unfolds */ | |
dhcp_free_reply(dhcp); | |
/* options present? */ | |
if (dhcp->p->tot_len > (sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN)) { | |
dhcp->options_in_len = dhcp->p->tot_len - (sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN); | |
dhcp->options_in = mem_malloc(dhcp->options_in_len); | |
if (dhcp->options_in == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_unfold_reply(): could not allocate dhcp->options\n")); | |
return ERR_MEM; | |
} | |
} | |
dhcp->msg_in = mem_malloc(sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN); | |
if (dhcp->msg_in == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_unfold_reply(): could not allocate dhcp->msg_in\n")); | |
mem_free((void *)dhcp->options_in); | |
dhcp->options_in = NULL; | |
return ERR_MEM; | |
} | |
/** copy the DHCP message without options */ | |
ret = pbuf_copy_partial(dhcp->p, dhcp->msg_in, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN, 0); | |
LWIP_ASSERT("ret == sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN", ret == sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_unfold_reply(): copied %"U16_F" bytes into dhcp->msg_in[]\n", | |
sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN)); | |
if (dhcp->options_in != NULL) { | |
/** copy the DHCP options */ | |
ret = pbuf_copy_partial(dhcp->p, dhcp->options_in, dhcp->options_in_len, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN); | |
LWIP_ASSERT("ret == dhcp->options_in_len", ret == dhcp->options_in_len); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_unfold_reply(): copied %"U16_F" bytes to dhcp->options_in[]\n", | |
dhcp->options_in_len)); | |
} | |
LWIP_UNUSED_ARG(ret); | |
return ERR_OK; | |
} | |
/** | |
* Free the incoming DHCP message including contiguous copy of | |
* its DHCP options. | |
* | |
*/ | |
static void dhcp_free_reply(struct dhcp *dhcp) | |
{ | |
if (dhcp->msg_in != NULL) { | |
mem_free((void *)dhcp->msg_in); | |
dhcp->msg_in = NULL; | |
} | |
if (dhcp->options_in) { | |
mem_free((void *)dhcp->options_in); | |
dhcp->options_in = NULL; | |
dhcp->options_in_len = 0; | |
} | |
LWIP_DEBUGF(DHCP_DEBUG, ("dhcp_free_reply(): free'd\n")); | |
} | |
/** | |
* If an incoming DHCP message is in response to us, then trigger the state machine | |
*/ | |
static void dhcp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port) | |
{ | |
struct netif *netif = (struct netif *)arg; | |
struct dhcp *dhcp = netif->dhcp; | |
struct dhcp_msg *reply_msg = (struct dhcp_msg *)p->payload; | |
u8_t *options_ptr; | |
u8_t msg_type; | |
u8_t i; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 3, ("dhcp_recv(pbuf = %p) from DHCP server %"U16_F".%"U16_F".%"U16_F".%"U16_F" port %"U16_F"\n", (void*)p, | |
(u16_t)(ntohl(addr->addr) >> 24 & 0xff), (u16_t)(ntohl(addr->addr) >> 16 & 0xff), | |
(u16_t)(ntohl(addr->addr) >> 8 & 0xff), (u16_t)(ntohl(addr->addr) & 0xff), port)); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("pbuf->len = %"U16_F"\n", p->len)); | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("pbuf->tot_len = %"U16_F"\n", p->tot_len)); | |
/* prevent warnings about unused arguments */ | |
LWIP_UNUSED_ARG(pcb); | |
LWIP_UNUSED_ARG(addr); | |
LWIP_UNUSED_ARG(port); | |
dhcp->p = p; | |
/* TODO: check packet length before reading them */ | |
if (reply_msg->op != DHCP_BOOTREPLY) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 1, ("not a DHCP reply message, but type %"U16_F"\n", (u16_t)reply_msg->op)); | |
goto free_pbuf_and_return; | |
} | |
/* iterate through hardware address and match against DHCP message */ | |
for (i = 0; i < netif->hwaddr_len; i++) { | |
if (netif->hwaddr[i] != reply_msg->chaddr[i]) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("netif->hwaddr[%"U16_F"]==%02"X16_F" != reply_msg->chaddr[%"U16_F"]==%02"X16_F"\n", | |
(u16_t)i, (u16_t)netif->hwaddr[i], (u16_t)i, (u16_t)reply_msg->chaddr[i])); | |
goto free_pbuf_and_return; | |
} | |
} | |
/* match transaction ID against what we expected */ | |
if (ntohl(reply_msg->xid) != dhcp->xid) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("transaction id mismatch reply_msg->xid(%"X32_F")!=dhcp->xid(%"X32_F")\n",ntohl(reply_msg->xid),dhcp->xid)); | |
goto free_pbuf_and_return; | |
} | |
/* option fields could be unfold? */ | |
if (dhcp_unfold_reply(dhcp) != ERR_OK) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("problem unfolding DHCP message - too short on memory?\n")); | |
goto free_pbuf_and_return; | |
} | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("searching DHCP_OPTION_MESSAGE_TYPE\n")); | |
/* obtain pointer to DHCP message type */ | |
options_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_MESSAGE_TYPE); | |
if (options_ptr == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 1, ("DHCP_OPTION_MESSAGE_TYPE option not found\n")); | |
goto free_pbuf_and_return; | |
} | |
/* read DHCP message type */ | |
msg_type = dhcp_get_option_byte(options_ptr + 2); | |
/* message type is DHCP ACK? */ | |
if (msg_type == DHCP_ACK) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 1, ("DHCP_ACK received\n")); | |
/* in requesting state? */ | |
if (dhcp->state == DHCP_REQUESTING) { | |
dhcp_handle_ack(netif); | |
dhcp->request_timeout = 0; | |
#if DHCP_DOES_ARP_CHECK | |
/* check if the acknowledged lease address is already in use */ | |
dhcp_check(netif); | |
#else | |
/* bind interface to the acknowledged lease address */ | |
dhcp_bind(netif); | |
#endif | |
} | |
/* already bound to the given lease address? */ | |
else if ((dhcp->state == DHCP_REBOOTING) || (dhcp->state == DHCP_REBINDING) || (dhcp->state == DHCP_RENEWING)) { | |
dhcp->request_timeout = 0; | |
dhcp_bind(netif); | |
} | |
} | |
/* received a DHCP_NAK in appropriate state? */ | |
else if ((msg_type == DHCP_NAK) && | |
((dhcp->state == DHCP_REBOOTING) || (dhcp->state == DHCP_REQUESTING) || | |
(dhcp->state == DHCP_REBINDING) || (dhcp->state == DHCP_RENEWING ))) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 1, ("DHCP_NAK received\n")); | |
dhcp->request_timeout = 0; | |
dhcp_handle_nak(netif); | |
} | |
/* received a DHCP_OFFER in DHCP_SELECTING state? */ | |
else if ((msg_type == DHCP_OFFER) && (dhcp->state == DHCP_SELECTING)) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 1, ("DHCP_OFFER received in DHCP_SELECTING state\n")); | |
dhcp->request_timeout = 0; | |
/* remember offered lease */ | |
dhcp_handle_offer(netif); | |
} | |
free_pbuf_and_return: | |
pbuf_free(p); | |
dhcp->p = NULL; | |
} | |
/** | |
* Create a DHCP request, fill in common headers | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static err_t | |
dhcp_create_request(struct netif *netif) | |
{ | |
struct dhcp *dhcp; | |
u16_t i; | |
LWIP_ERROR("dhcp_create_request: netif != NULL", (netif != NULL), return ERR_ARG;); | |
dhcp = netif->dhcp; | |
LWIP_ERROR("dhcp_create_request: dhcp != NULL", (dhcp != NULL), return ERR_VAL;); | |
LWIP_ASSERT("dhcp_create_request: dhcp->p_out == NULL", dhcp->p_out == NULL); | |
LWIP_ASSERT("dhcp_create_request: dhcp->msg_out == NULL", dhcp->msg_out == NULL); | |
dhcp->p_out = pbuf_alloc(PBUF_TRANSPORT, sizeof(struct dhcp_msg), PBUF_RAM); | |
if (dhcp->p_out == NULL) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("dhcp_create_request(): could not allocate pbuf\n")); | |
return ERR_MEM; | |
} | |
LWIP_ASSERT("dhcp_create_request: check that first pbuf can hold struct dhcp_msg", | |
(dhcp->p_out->len >= sizeof(struct dhcp_msg))); | |
/* give unique transaction identifier to this request */ | |
dhcp->xid = xid++; | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("transaction id xid++(%"X32_F") dhcp->xid(%"U32_F")\n",xid,dhcp->xid)); | |
dhcp->msg_out = (struct dhcp_msg *)dhcp->p_out->payload; | |
dhcp->msg_out->op = DHCP_BOOTREQUEST; | |
/* TODO: make link layer independent */ | |
dhcp->msg_out->htype = DHCP_HTYPE_ETH; | |
/* TODO: make link layer independent */ | |
dhcp->msg_out->hlen = DHCP_HLEN_ETH; | |
dhcp->msg_out->hops = 0; | |
dhcp->msg_out->xid = htonl(dhcp->xid); | |
dhcp->msg_out->secs = 0; | |
dhcp->msg_out->flags = 0; | |
dhcp->msg_out->ciaddr.addr = netif->ip_addr.addr; | |
dhcp->msg_out->yiaddr.addr = 0; | |
dhcp->msg_out->siaddr.addr = 0; | |
dhcp->msg_out->giaddr.addr = 0; | |
for (i = 0; i < DHCP_CHADDR_LEN; i++) { | |
/* copy netif hardware address, pad with zeroes */ | |
dhcp->msg_out->chaddr[i] = (i < netif->hwaddr_len) ? netif->hwaddr[i] : 0/* pad byte*/; | |
} | |
for (i = 0; i < DHCP_SNAME_LEN; i++) { | |
dhcp->msg_out->sname[i] = 0; | |
} | |
for (i = 0; i < DHCP_FILE_LEN; i++) { | |
dhcp->msg_out->file[i] = 0; | |
} | |
dhcp->msg_out->cookie = htonl(0x63825363UL); | |
dhcp->options_out_len = 0; | |
/* fill options field with an incrementing array (for debugging purposes) */ | |
for (i = 0; i < DHCP_OPTIONS_LEN; i++) { | |
dhcp->msg_out->options[i] = (u8_t)i; /* for debugging only, no matter if truncated */ | |
} | |
return ERR_OK; | |
} | |
/** | |
* Free previously allocated memory used to send a DHCP request. | |
* | |
* @param netif the netif under DHCP control | |
*/ | |
static void | |
dhcp_delete_request(struct netif *netif) | |
{ | |
struct dhcp *dhcp; | |
LWIP_ERROR("dhcp_delete_request: netif != NULL", (netif != NULL), return;); | |
dhcp = netif->dhcp; | |
LWIP_ERROR("dhcp_delete_request: dhcp != NULL", (dhcp != NULL), return;); | |
LWIP_ASSERT("dhcp_delete_request: dhcp->p_out != NULL", dhcp->p_out != NULL); | |
LWIP_ASSERT("dhcp_delete_request: dhcp->msg_out != NULL", dhcp->msg_out != NULL); | |
if (dhcp->p_out != NULL) { | |
pbuf_free(dhcp->p_out); | |
} | |
dhcp->p_out = NULL; | |
dhcp->msg_out = NULL; | |
} | |
/** | |
* Add a DHCP message trailer | |
* | |
* Adds the END option to the DHCP message, and if | |
* necessary, up to three padding bytes. | |
* | |
* @param dhcp DHCP state structure | |
*/ | |
static void | |
dhcp_option_trailer(struct dhcp *dhcp) | |
{ | |
LWIP_ERROR("dhcp_option_trailer: dhcp != NULL", (dhcp != NULL), return;); | |
LWIP_ASSERT("dhcp_option_trailer: dhcp->msg_out != NULL\n", dhcp->msg_out != NULL); | |
LWIP_ASSERT("dhcp_option_trailer: dhcp->options_out_len < DHCP_OPTIONS_LEN\n", dhcp->options_out_len < DHCP_OPTIONS_LEN); | |
dhcp->msg_out->options[dhcp->options_out_len++] = DHCP_OPTION_END; | |
/* packet is too small, or not 4 byte aligned? */ | |
while ((dhcp->options_out_len < DHCP_MIN_OPTIONS_LEN) || (dhcp->options_out_len & 3)) { | |
/* 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)); */ | |
LWIP_ASSERT("dhcp_option_trailer: dhcp->options_out_len < DHCP_OPTIONS_LEN\n", dhcp->options_out_len < DHCP_OPTIONS_LEN); | |
/* add a fill/padding byte */ | |
dhcp->msg_out->options[dhcp->options_out_len++] = 0; | |
} | |
} | |
/** | |
* Find the offset of a DHCP option inside the DHCP message. | |
* | |
* @param dhcp DHCP client | |
* @param option_type | |
* | |
* @return a byte offset into the UDP message where the option was found, or | |
* zero if the given option was not found. | |
*/ | |
static u8_t *dhcp_get_option_ptr(struct dhcp *dhcp, u8_t option_type) | |
{ | |
u8_t overload = DHCP_OVERLOAD_NONE; | |
/* options available? */ | |
if ((dhcp->options_in != NULL) && (dhcp->options_in_len > 0)) { | |
/* start with options field */ | |
u8_t *options = (u8_t *)dhcp->options_in; | |
u16_t offset = 0; | |
/* at least 1 byte to read and no end marker, then at least 3 bytes to read? */ | |
while ((offset < dhcp->options_in_len) && (options[offset] != DHCP_OPTION_END)) { | |
/* LWIP_DEBUGF(DHCP_DEBUG, ("msg_offset=%"U16_F", q->len=%"U16_F, msg_offset, q->len)); */ | |
/* are the sname and/or file field overloaded with options? */ | |
if (options[offset] == DHCP_OPTION_OVERLOAD) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 2, ("overloaded message detected\n")); | |
/* skip option type and length */ | |
offset += 2; | |
overload = options[offset++]; | |
} | |
/* requested option found */ | |
else if (options[offset] == option_type) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("option found at offset %"U16_F" in options\n", offset)); | |
return &options[offset]; | |
/* skip option */ | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG, ("skipping option %"U16_F" in options\n", options[offset])); | |
/* skip option type */ | |
offset++; | |
/* skip option length, and then length bytes */ | |
offset += 1 + options[offset]; | |
} | |
} | |
/* is this an overloaded message? */ | |
if (overload != DHCP_OVERLOAD_NONE) { | |
u16_t field_len; | |
if (overload == DHCP_OVERLOAD_FILE) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 1, ("overloaded file field\n")); | |
options = (u8_t *)&dhcp->msg_in->file; | |
field_len = DHCP_FILE_LEN; | |
} else if (overload == DHCP_OVERLOAD_SNAME) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 1, ("overloaded sname field\n")); | |
options = (u8_t *)&dhcp->msg_in->sname; | |
field_len = DHCP_SNAME_LEN; | |
/* TODO: check if else if () is necessary */ | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE | 1, ("overloaded sname and file field\n")); | |
options = (u8_t *)&dhcp->msg_in->sname; | |
field_len = DHCP_FILE_LEN + DHCP_SNAME_LEN; | |
} | |
offset = 0; | |
/* at least 1 byte to read and no end marker */ | |
while ((offset < field_len) && (options[offset] != DHCP_OPTION_END)) { | |
if (options[offset] == option_type) { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("option found at offset=%"U16_F"\n", offset)); | |
return &options[offset]; | |
/* skip option */ | |
} else { | |
LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("skipping option %"U16_F"\n", options[offset])); | |
/* skip option type */ | |
offset++; | |
offset += 1 + options[offset]; | |
} | |
} | |
} | |
} | |
return NULL; | |
} | |
/** | |
* Return the byte of DHCP option data. | |
* | |
* @param client DHCP client. | |
* @param ptr pointer obtained by dhcp_get_option_ptr(). | |
* | |
* @return byte value at the given address. | |
*/ | |
static u8_t | |
dhcp_get_option_byte(u8_t *ptr) | |
{ | |
LWIP_DEBUGF(DHCP_DEBUG, ("option byte value=%"U16_F"\n", (u16_t)(*ptr))); | |
return *ptr; | |
} | |
#if 0 /* currently unused */ | |
/** | |
* Return the 16-bit value of DHCP option data. | |
* | |
* @param client DHCP client. | |
* @param ptr pointer obtained by dhcp_get_option_ptr(). | |
* | |
* @return byte value at the given address. | |
*/ | |
static u16_t | |
dhcp_get_option_short(u8_t *ptr) | |
{ | |
u16_t value; | |
value = *ptr++ << 8; | |
value |= *ptr; | |
LWIP_DEBUGF(DHCP_DEBUG, ("option short value=%"U16_F"\n", value)); | |
return value; | |
} | |
#endif | |
/** | |
* Return the 32-bit value of DHCP option data. | |
* | |
* @param client DHCP client. | |
* @param ptr pointer obtained by dhcp_get_option_ptr(). | |
* | |
* @return byte value at the given address. | |
*/ | |
static u32_t dhcp_get_option_long(u8_t *ptr) | |
{ | |
u32_t value; | |
value = (u32_t)(*ptr++) << 24; | |
value |= (u32_t)(*ptr++) << 16; | |
value |= (u32_t)(*ptr++) << 8; | |
value |= (u32_t)(*ptr++); | |
LWIP_DEBUGF(DHCP_DEBUG, ("option long value=%"U32_F"\n", value)); | |
return value; | |
} | |
#endif /* LWIP_DHCP */ |