4 * Dynamic Host Configuration Protocol client
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9 * Copyright (c) 2001-2004 Leon Woestenberg <leon.woestenberg@gmx.net>
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10 * Copyright (c) 2001-2004 Axon Digital Design B.V., The Netherlands.
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11 * All rights reserved.
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13 * Redistribution and use in source and binary forms, with or without modification,
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14 * are permitted provided that the following conditions are met:
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16 * 1. Redistributions of source code must retain the above copyright notice,
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17 * this list of conditions and the following disclaimer.
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18 * 2. Redistributions in binary form must reproduce the above copyright notice,
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19 * this list of conditions and the following disclaimer in the documentation
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20 * and/or other materials provided with the distribution.
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21 * 3. The name of the author may not be used to endorse or promote products
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22 * derived from this software without specific prior written permission.
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24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
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25 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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26 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
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27 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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28 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
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29 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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32 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
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35 * This file is a contribution to the lwIP TCP/IP stack.
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36 * The Swedish Institute of Computer Science and Adam Dunkels
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37 * are specifically granted permission to redistribute this
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40 * Author: Leon Woestenberg <leon.woestenberg@gmx.net>
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42 * This is a DHCP client for the lwIP TCP/IP stack. It aims to conform
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43 * with RFC 2131 and RFC 2132.
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46 * - Proper parsing of DHCP messages exploiting file/sname field overloading.
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47 * - Add JavaDoc style documentation (API, internals).
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48 * - Support for interfaces other than Ethernet (SLIP, PPP, ...)
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50 * Please coordinate changes and requests with Leon Woestenberg
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51 * <leon.woestenberg@gmx.net>
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53 * Integration with your code:
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56 * #define DHCP_COARSE_TIMER_SECS (recommended 60 which is a minute)
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57 * #define DHCP_FINE_TIMER_MSECS (recommended 500 which equals TCP coarse timer)
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59 * Then have your application call dhcp_coarse_tmr() and
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60 * dhcp_fine_tmr() on the defined intervals.
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62 * dhcp_start(struct netif *netif);
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63 * starts a DHCP client instance which configures the interface by
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64 * obtaining an IP address lease and maintaining it.
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66 * Use dhcp_release(netif) to end the lease and use dhcp_stop(netif)
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67 * to remove the DHCP client.
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73 #include "lwip/stats.h"
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74 #include "lwip/mem.h"
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75 #include "lwip/udp.h"
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76 #include "lwip/ip_addr.h"
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77 #include "lwip/netif.h"
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78 #include "lwip/inet.h"
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79 #include "netif/etharp.h"
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81 #include "lwip/sys.h"
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82 #include "lwip/opt.h"
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83 #include "lwip/dhcp.h"
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85 #if LWIP_DHCP /* don't build if not configured for use in lwipopt.h */
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87 /** global transaction identifier, must be
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88 * unique for each DHCP request. We simply increment, starting
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89 * with this value (easy to match with a packet analyzer) */
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90 static u32_t xid = 0xABCD0000;
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92 /** DHCP client state machine functions */
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93 static void dhcp_handle_ack(struct netif *netif);
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94 static void dhcp_handle_nak(struct netif *netif);
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95 static void dhcp_handle_offer(struct netif *netif);
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97 static err_t dhcp_discover(struct netif *netif);
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98 static err_t dhcp_select(struct netif *netif);
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99 static void dhcp_check(struct netif *netif);
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100 static void dhcp_bind(struct netif *netif);
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101 static err_t dhcp_decline(struct netif *netif);
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102 static err_t dhcp_rebind(struct netif *netif);
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103 static void dhcp_set_state(struct dhcp *dhcp, u8_t new_state);
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105 /** receive, unfold, parse and free incoming messages */
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106 static void dhcp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port);
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107 static err_t dhcp_unfold_reply(struct dhcp *dhcp);
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108 static u8_t *dhcp_get_option_ptr(struct dhcp *dhcp, u8_t option_type);
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109 static u8_t dhcp_get_option_byte(u8_t *ptr);
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110 static u16_t dhcp_get_option_short(u8_t *ptr);
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111 static u32_t dhcp_get_option_long(u8_t *ptr);
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112 static void dhcp_free_reply(struct dhcp *dhcp);
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114 /** set the DHCP timers */
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115 static void dhcp_timeout(struct netif *netif);
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116 static void dhcp_t1_timeout(struct netif *netif);
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117 static void dhcp_t2_timeout(struct netif *netif);
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119 /** build outgoing messages */
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120 /** create a DHCP request, fill in common headers */
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121 static err_t dhcp_create_request(struct netif *netif);
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122 /** free a DHCP request */
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123 static void dhcp_delete_request(struct netif *netif);
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124 /** add a DHCP option (type, then length in bytes) */
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125 static void dhcp_option(struct dhcp *dhcp, u8_t option_type, u8_t option_len);
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126 /** add option values */
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127 static void dhcp_option_byte(struct dhcp *dhcp, u8_t value);
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128 static void dhcp_option_short(struct dhcp *dhcp, u16_t value);
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129 static void dhcp_option_long(struct dhcp *dhcp, u32_t value);
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130 /** always add the DHCP options trailer to end and pad */
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131 static void dhcp_option_trailer(struct dhcp *dhcp);
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134 * Back-off the DHCP client (because of a received NAK response).
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136 * Back-off the DHCP client because of a received NAK. Receiving a
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137 * NAK means the client asked for something non-sensible, for
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138 * example when it tries to renew a lease obtained on another network.
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140 * We back-off and will end up restarting a fresh DHCP negotiation later.
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142 * @param state pointer to DHCP state structure
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144 static void dhcp_handle_nak(struct netif *netif) {
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145 struct dhcp *dhcp = netif->dhcp;
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146 u16_t msecs = 10 * 1000;
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147 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_handle_nak(netif=%p) %c%c%"U16_F"\n",
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148 (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
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149 dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
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150 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_handle_nak(): set request timeout %"U16_F" msecs\n", msecs));
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151 dhcp_set_state(dhcp, DHCP_BACKING_OFF);
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155 * Checks if the offered IP address is already in use.
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157 * It does so by sending an ARP request for the offered address and
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158 * entering CHECKING state. If no ARP reply is received within a small
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159 * interval, the address is assumed to be free for use by us.
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161 static void dhcp_check(struct netif *netif)
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163 struct dhcp *dhcp = netif->dhcp;
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166 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_check(netif=%p) %c%c\n", (void *)netif, (s16_t)netif->name[0],
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167 (s16_t)netif->name[1]));
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168 /* create an ARP query for the offered IP address, expecting that no host
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169 responds, as the IP address should not be in use. */
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170 result = etharp_query(netif, &dhcp->offered_ip_addr, NULL);
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171 if (result != ERR_OK) {
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172 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_check: could not perform ARP query\n"));
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176 dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
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177 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_check(): set request timeout %"U16_F" msecs\n", msecs));
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178 dhcp_set_state(dhcp, DHCP_CHECKING);
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182 * Remember the configuration offered by a DHCP server.
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184 * @param state pointer to DHCP state structure
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186 static void dhcp_handle_offer(struct netif *netif)
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188 struct dhcp *dhcp = netif->dhcp;
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189 /* obtain the server address */
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190 u8_t *option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_SERVER_ID);
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191 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_handle_offer(netif=%p) %c%c%"U16_F"\n",
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192 (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
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193 if (option_ptr != NULL)
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195 dhcp->server_ip_addr.addr = htonl(dhcp_get_option_long(&option_ptr[2]));
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196 LWIP_DEBUGF(DHCP_DEBUG | DBG_STATE, ("dhcp_handle_offer(): server 0x%08"X32_F"\n", dhcp->server_ip_addr.addr));
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197 /* remember offered address */
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198 ip_addr_set(&dhcp->offered_ip_addr, (struct ip_addr *)&dhcp->msg_in->yiaddr);
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199 LWIP_DEBUGF(DHCP_DEBUG | DBG_STATE, ("dhcp_handle_offer(): offer for 0x%08"X32_F"\n", dhcp->offered_ip_addr.addr));
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201 dhcp_select(netif);
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206 * Select a DHCP server offer out of all offers.
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208 * Simply select the first offer received.
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210 * @param netif the netif under DHCP control
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211 * @return lwIP specific error (see error.h)
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213 static err_t dhcp_select(struct netif *netif)
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215 struct dhcp *dhcp = netif->dhcp;
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218 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_select(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
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220 /* create and initialize the DHCP message header */
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221 result = dhcp_create_request(netif);
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222 if (result == ERR_OK)
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224 dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN);
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225 dhcp_option_byte(dhcp, DHCP_REQUEST);
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227 dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
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228 dhcp_option_short(dhcp, 576);
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230 /* MUST request the offered IP address */
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231 dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
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232 dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr));
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234 dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4);
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235 dhcp_option_long(dhcp, ntohl(dhcp->server_ip_addr.addr));
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237 dhcp_option(dhcp, DHCP_OPTION_PARAMETER_REQUEST_LIST, 4/*num options*/);
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238 dhcp_option_byte(dhcp, DHCP_OPTION_SUBNET_MASK);
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239 dhcp_option_byte(dhcp, DHCP_OPTION_ROUTER);
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240 dhcp_option_byte(dhcp, DHCP_OPTION_BROADCAST);
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241 dhcp_option_byte(dhcp, DHCP_OPTION_DNS_SERVER);
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243 dhcp_option_trailer(dhcp);
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244 /* shrink the pbuf to the actual content length */
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245 pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
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247 /* TODO: we really should bind to a specific local interface here
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248 but we cannot specify an unconfigured netif as it is addressless */
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249 udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
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250 /* send broadcast to any DHCP server */
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251 udp_connect(dhcp->pcb, IP_ADDR_BROADCAST, DHCP_SERVER_PORT);
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252 udp_send(dhcp->pcb, dhcp->p_out);
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253 /* reconnect to any (or to server here?!) */
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254 udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
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255 dhcp_delete_request(netif);
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256 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_select: REQUESTING\n"));
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257 dhcp_set_state(dhcp, DHCP_REQUESTING);
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259 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_select: could not allocate DHCP request\n"));
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262 msecs = dhcp->tries < 4 ? dhcp->tries * 1000 : 4 * 1000;
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263 dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
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264 LWIP_DEBUGF(DHCP_DEBUG | DBG_STATE, ("dhcp_select(): set request timeout %"U32_F" msecs\n", msecs));
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269 * The DHCP timer that checks for lease renewal/rebind timeouts.
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272 void dhcp_coarse_tmr()
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274 struct netif *netif = netif_list;
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275 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_coarse_tmr()\n"));
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276 /* iterate through all network interfaces */
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277 while (netif != NULL) {
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278 /* only act on DHCP configured interfaces */
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279 if (netif->dhcp != NULL) {
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280 /* timer is active (non zero), and triggers (zeroes) now? */
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281 if (netif->dhcp->t2_timeout-- == 1) {
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282 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_coarse_tmr(): t2 timeout\n"));
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283 /* this clients' rebind timeout triggered */
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284 dhcp_t2_timeout(netif);
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285 /* timer is active (non zero), and triggers (zeroes) now */
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286 } else if (netif->dhcp->t1_timeout-- == 1) {
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287 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_coarse_tmr(): t1 timeout\n"));
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288 /* this clients' renewal timeout triggered */
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289 dhcp_t1_timeout(netif);
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292 /* proceed to next netif */
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293 netif = netif->next;
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298 * DHCP transaction timeout handling
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300 * A DHCP server is expected to respond within a short period of time.
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301 * This timer checks whether an outstanding DHCP request is timed out.
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304 void dhcp_fine_tmr()
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306 struct netif *netif = netif_list;
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307 /* loop through netif's */
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308 while (netif != NULL) {
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309 /* only act on DHCP configured interfaces */
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310 if (netif->dhcp != NULL) {
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311 /* timer is active (non zero), and is about to trigger now */
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312 if (netif->dhcp->request_timeout-- == 1) {
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313 /* { netif->dhcp->request_timeout == 0 } */
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314 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_fine_tmr(): request timeout\n"));
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315 /* this clients' request timeout triggered */
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316 dhcp_timeout(netif);
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319 /* proceed to next network interface */
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320 netif = netif->next;
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325 * A DHCP negotiation transaction, or ARP request, has timed out.
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327 * The timer that was started with the DHCP or ARP request has
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328 * timed out, indicating no response was received in time.
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330 * @param netif the netif under DHCP control
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333 static void dhcp_timeout(struct netif *netif)
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335 struct dhcp *dhcp = netif->dhcp;
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336 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_timeout()\n"));
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337 /* back-off period has passed, or server selection timed out */
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338 if ((dhcp->state == DHCP_BACKING_OFF) || (dhcp->state == DHCP_SELECTING)) {
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339 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_timeout(): restarting discovery\n"));
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340 dhcp_discover(netif);
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341 /* receiving the requested lease timed out */
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342 } else if (dhcp->state == DHCP_REQUESTING) {
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343 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_timeout(): REQUESTING, DHCP request timed out\n"));
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344 if (dhcp->tries <= 5) {
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345 dhcp_select(netif);
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347 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_timeout(): REQUESTING, releasing, restarting\n"));
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348 dhcp_release(netif);
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349 dhcp_discover(netif);
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351 /* received no ARP reply for the offered address (which is good) */
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352 } else if (dhcp->state == DHCP_CHECKING) {
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353 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_timeout(): CHECKING, ARP request timed out\n"));
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354 if (dhcp->tries <= 1) {
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356 /* no ARP replies on the offered address,
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357 looks like the IP address is indeed free */
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359 /* bind the interface to the offered address */
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363 /* did not get response to renew request? */
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364 else if (dhcp->state == DHCP_RENEWING) {
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365 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_timeout(): RENEWING, DHCP request timed out\n"));
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366 /* just retry renewal */
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367 /* note that the rebind timer will eventually time-out if renew does not work */
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369 /* did not get response to rebind request? */
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370 } else if (dhcp->state == DHCP_REBINDING) {
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371 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_timeout(): REBINDING, DHCP request timed out\n"));
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372 if (dhcp->tries <= 8) {
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373 dhcp_rebind(netif);
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375 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_timeout(): RELEASING, DISCOVERING\n"));
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376 dhcp_release(netif);
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377 dhcp_discover(netif);
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383 * The renewal period has timed out.
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385 * @param netif the netif under DHCP control
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387 static void dhcp_t1_timeout(struct netif *netif)
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389 struct dhcp *dhcp = netif->dhcp;
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390 LWIP_DEBUGF(DHCP_DEBUG | DBG_STATE, ("dhcp_t1_timeout()\n"));
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391 if ((dhcp->state == DHCP_REQUESTING) || (dhcp->state == DHCP_BOUND) || (dhcp->state == DHCP_RENEWING)) {
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392 /* just retry to renew - note that the rebind timer (t2) will
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393 * eventually time-out if renew tries fail. */
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394 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_t1_timeout(): must renew\n"));
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400 * The rebind period has timed out.
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403 static void dhcp_t2_timeout(struct netif *netif)
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405 struct dhcp *dhcp = netif->dhcp;
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406 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_t2_timeout()\n"));
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407 if ((dhcp->state == DHCP_REQUESTING) || (dhcp->state == DHCP_BOUND) || (dhcp->state == DHCP_RENEWING)) {
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408 /* just retry to rebind */
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409 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_t2_timeout(): must rebind\n"));
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410 dhcp_rebind(netif);
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416 * @param netif the netif under DHCP control
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418 static void dhcp_handle_ack(struct netif *netif)
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420 struct dhcp *dhcp = netif->dhcp;
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422 /* clear options we might not get from the ACK */
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423 dhcp->offered_sn_mask.addr = 0;
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424 dhcp->offered_gw_addr.addr = 0;
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425 dhcp->offered_bc_addr.addr = 0;
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427 /* lease time given? */
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428 option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_LEASE_TIME);
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429 if (option_ptr != NULL) {
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430 /* remember offered lease time */
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431 dhcp->offered_t0_lease = dhcp_get_option_long(option_ptr + 2);
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433 /* renewal period given? */
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434 option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_T1);
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435 if (option_ptr != NULL) {
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436 /* remember given renewal period */
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437 dhcp->offered_t1_renew = dhcp_get_option_long(option_ptr + 2);
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439 /* calculate safe periods for renewal */
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440 dhcp->offered_t1_renew = dhcp->offered_t0_lease / 2;
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443 /* renewal period given? */
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444 option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_T2);
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445 if (option_ptr != NULL) {
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446 /* remember given rebind period */
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447 dhcp->offered_t2_rebind = dhcp_get_option_long(option_ptr + 2);
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449 /* calculate safe periods for rebinding */
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450 dhcp->offered_t2_rebind = dhcp->offered_t0_lease;
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453 /* (y)our internet address */
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454 ip_addr_set(&dhcp->offered_ip_addr, &dhcp->msg_in->yiaddr);
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458 * TODO: we must check if the file field is not overloaded by DHCP options!
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461 /* boot server address */
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462 ip_addr_set(&dhcp->offered_si_addr, &dhcp->msg_in->siaddr);
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463 /* boot file name */
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464 if (dhcp->msg_in->file[0]) {
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465 dhcp->boot_file_name = mem_malloc(strlen(dhcp->msg_in->file) + 1);
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466 strcpy(dhcp->boot_file_name, dhcp->msg_in->file);
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471 option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_SUBNET_MASK);
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472 /* subnet mask given? */
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473 if (option_ptr != NULL) {
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474 dhcp->offered_sn_mask.addr = htonl(dhcp_get_option_long(&option_ptr[2]));
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477 /* gateway router */
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478 option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_ROUTER);
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479 if (option_ptr != NULL) {
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480 dhcp->offered_gw_addr.addr = htonl(dhcp_get_option_long(&option_ptr[2]));
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483 /* broadcast address */
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484 option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_BROADCAST);
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485 if (option_ptr != NULL) {
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486 dhcp->offered_bc_addr.addr = htonl(dhcp_get_option_long(&option_ptr[2]));
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490 option_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_DNS_SERVER);
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491 if (option_ptr != NULL) {
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493 dhcp->dns_count = dhcp_get_option_byte(&option_ptr[1]);
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494 /* limit to at most DHCP_MAX_DNS DNS servers */
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495 if (dhcp->dns_count > DHCP_MAX_DNS) dhcp->dns_count = DHCP_MAX_DNS;
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496 for (n = 0; n < dhcp->dns_count; n++)
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498 dhcp->offered_dns_addr[n].addr = htonl(dhcp_get_option_long(&option_ptr[2+(n<<2)]));
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504 * Start DHCP negotiation for a network interface.
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506 * If no DHCP client instance was attached to this interface,
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507 * a new client is created first. If a DHCP client instance
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508 * was already present, it restarts negotiation.
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510 * @param netif The lwIP network interface
\r
511 * @return lwIP error code
\r
512 * - ERR_OK - No error
\r
513 * - ERR_MEM - Out of memory
\r
516 err_t dhcp_start(struct netif *netif)
\r
518 struct dhcp *dhcp = netif->dhcp;
\r
519 err_t result = ERR_OK;
\r
521 LWIP_ASSERT("netif != NULL", netif != NULL);
\r
522 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_start(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
\r
523 netif->flags &= ~NETIF_FLAG_DHCP;
\r
525 /* no DHCP client attached yet? */
\r
526 if (dhcp == NULL) {
\r
527 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_start(): starting new DHCP client\n"));
\r
528 dhcp = mem_malloc(sizeof(struct dhcp));
\r
529 if (dhcp == NULL) {
\r
530 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_start(): could not allocate dhcp\n"));
\r
533 /* store this dhcp client in the netif */
\r
534 netif->dhcp = dhcp;
\r
535 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_start(): allocated dhcp"));
\r
536 /* already has DHCP client attached */
\r
538 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE | 3, ("dhcp_start(): restarting DHCP configuration\n"));
\r
541 /* clear data structure */
\r
542 memset(dhcp, 0, sizeof(struct dhcp));
\r
543 /* allocate UDP PCB */
\r
544 dhcp->pcb = udp_new();
\r
545 if (dhcp->pcb == NULL) {
\r
546 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_start(): could not obtain pcb\n"));
\r
547 mem_free((void *)dhcp);
\r
548 netif->dhcp = dhcp = NULL;
\r
551 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_start(): starting DHCP configuration\n"));
\r
552 /* (re)start the DHCP negotiation */
\r
553 result = dhcp_discover(netif);
\r
554 if (result != ERR_OK) {
\r
555 /* free resources allocated above */
\r
559 netif->flags |= NETIF_FLAG_DHCP;
\r
564 * Inform a DHCP server of our manual configuration.
\r
566 * This informs DHCP servers of our fixed IP address configuration
\r
567 * by sending an INFORM message. It does not involve DHCP address
\r
568 * configuration, it is just here to be nice to the network.
\r
570 * @param netif The lwIP network interface
\r
573 void dhcp_inform(struct netif *netif)
\r
576 err_t result = ERR_OK;
\r
577 dhcp = mem_malloc(sizeof(struct dhcp));
\r
578 if (dhcp == NULL) {
\r
579 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_inform(): could not allocate dhcp\n"));
\r
582 netif->dhcp = dhcp;
\r
583 memset(dhcp, 0, sizeof(struct dhcp));
\r
585 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_inform(): allocated dhcp\n"));
\r
586 dhcp->pcb = udp_new();
\r
587 if (dhcp->pcb == NULL) {
\r
588 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_inform(): could not obtain pcb"));
\r
589 mem_free((void *)dhcp);
\r
592 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_inform(): created new udp pcb\n"));
\r
593 /* create and initialize the DHCP message header */
\r
594 result = dhcp_create_request(netif);
\r
595 if (result == ERR_OK) {
\r
597 dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN);
\r
598 dhcp_option_byte(dhcp, DHCP_INFORM);
\r
600 dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
\r
601 /* TODO: use netif->mtu ?! */
\r
602 dhcp_option_short(dhcp, 576);
\r
604 dhcp_option_trailer(dhcp);
\r
606 pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
\r
608 udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
\r
609 udp_connect(dhcp->pcb, IP_ADDR_BROADCAST, DHCP_SERVER_PORT);
\r
610 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_inform: INFORMING\n"));
\r
611 udp_send(dhcp->pcb, dhcp->p_out);
\r
612 udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
\r
613 dhcp_delete_request(netif);
\r
615 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_inform: could not allocate DHCP request\n"));
\r
620 if (dhcp->pcb != NULL) udp_remove(dhcp->pcb);
\r
622 mem_free((void *)dhcp);
\r
623 netif->dhcp = NULL;
\r
627 #if DHCP_DOES_ARP_CHECK
\r
629 * Match an ARP reply with the offered IP address.
\r
631 * @param addr The IP address we received a reply from
\r
634 void dhcp_arp_reply(struct netif *netif, struct ip_addr *addr)
\r
636 LWIP_ASSERT("netif != NULL", netif != NULL);
\r
637 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_arp_reply()\n"));
\r
638 /* is a DHCP client doing an ARP check? */
\r
639 if ((netif->dhcp != NULL) && (netif->dhcp->state == DHCP_CHECKING)) {
\r
640 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_arp_reply(): CHECKING, arp reply for 0x%08"X32_F"\n", addr->addr));
\r
641 /* did a host respond with the address we
\r
642 were offered by the DHCP server? */
\r
643 if (ip_addr_cmp(addr, &netif->dhcp->offered_ip_addr)) {
\r
644 /* we will not accept the offered address */
\r
645 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE | 1, ("dhcp_arp_reply(): arp reply matched with offered address, declining\n"));
\r
646 dhcp_decline(netif);
\r
652 * Decline an offered lease.
\r
654 * Tell the DHCP server we do not accept the offered address.
\r
655 * One reason to decline the lease is when we find out the address
\r
656 * is already in use by another host (through ARP).
\r
658 static err_t dhcp_decline(struct netif *netif)
\r
660 struct dhcp *dhcp = netif->dhcp;
\r
661 err_t result = ERR_OK;
\r
663 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_decline()\n"));
\r
664 dhcp_set_state(dhcp, DHCP_BACKING_OFF);
\r
665 /* create and initialize the DHCP message header */
\r
666 result = dhcp_create_request(netif);
\r
667 if (result == ERR_OK)
\r
669 dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN);
\r
670 dhcp_option_byte(dhcp, DHCP_DECLINE);
\r
672 dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
\r
673 dhcp_option_short(dhcp, 576);
\r
675 dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
\r
676 dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr));
\r
678 dhcp_option_trailer(dhcp);
\r
679 /* resize pbuf to reflect true size of options */
\r
680 pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
\r
682 udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
\r
683 /* @todo: should we really connect here? we are performing sendto() */
\r
684 udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
\r
685 /* per section 4.4.4, broadcast DECLINE messages */
\r
686 udp_sendto(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT);
\r
687 dhcp_delete_request(netif);
\r
688 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_decline: BACKING OFF\n"));
\r
690 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_decline: could not allocate DHCP request\n"));
\r
694 dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
\r
695 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_decline(): set request timeout %"U16_F" msecs\n", msecs));
\r
702 * Start the DHCP process, discover a DHCP server.
\r
705 static err_t dhcp_discover(struct netif *netif)
\r
707 struct dhcp *dhcp = netif->dhcp;
\r
708 err_t result = ERR_OK;
\r
710 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_discover()\n"));
\r
711 ip_addr_set(&dhcp->offered_ip_addr, IP_ADDR_ANY);
\r
712 /* create and initialize the DHCP message header */
\r
713 result = dhcp_create_request(netif);
\r
714 if (result == ERR_OK)
\r
716 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_discover: making request\n"));
\r
717 dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN);
\r
718 dhcp_option_byte(dhcp, DHCP_DISCOVER);
\r
720 dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
\r
721 dhcp_option_short(dhcp, 576);
\r
723 dhcp_option(dhcp, DHCP_OPTION_PARAMETER_REQUEST_LIST, 4/*num options*/);
\r
724 dhcp_option_byte(dhcp, DHCP_OPTION_SUBNET_MASK);
\r
725 dhcp_option_byte(dhcp, DHCP_OPTION_ROUTER);
\r
726 dhcp_option_byte(dhcp, DHCP_OPTION_BROADCAST);
\r
727 dhcp_option_byte(dhcp, DHCP_OPTION_DNS_SERVER);
\r
729 dhcp_option_trailer(dhcp);
\r
731 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_discover: realloc()ing\n"));
\r
732 pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
\r
734 /* set receive callback function with netif as user data */
\r
735 udp_recv(dhcp->pcb, dhcp_recv, netif);
\r
736 udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
\r
737 udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
\r
738 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_discover: sendto(DISCOVER, IP_ADDR_BROADCAST, DHCP_SERVER_PORT)\n"));
\r
739 udp_sendto(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT);
\r
740 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_discover: deleting()ing\n"));
\r
741 dhcp_delete_request(netif);
\r
742 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_discover: SELECTING\n"));
\r
743 dhcp_set_state(dhcp, DHCP_SELECTING);
\r
745 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_discover: could not allocate DHCP request\n"));
\r
748 msecs = dhcp->tries < 4 ? (dhcp->tries + 1) * 1000 : 10 * 1000;
\r
749 dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
\r
750 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_discover(): set request timeout %"U16_F" msecs\n", msecs));
\r
756 * Bind the interface to the offered IP address.
\r
758 * @param netif network interface to bind to the offered address
\r
760 static void dhcp_bind(struct netif *netif)
\r
762 struct dhcp *dhcp = netif->dhcp;
\r
763 struct ip_addr sn_mask, gw_addr;
\r
764 LWIP_ASSERT("dhcp_bind: netif != NULL", netif != NULL);
\r
765 LWIP_ASSERT("dhcp_bind: dhcp != NULL", dhcp != NULL);
\r
766 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_bind(netif=%p) %c%c%"U16_F"\n", (void*)netif, netif->name[0], netif->name[1], (u16_t)netif->num));
\r
768 /* temporary DHCP lease? */
\r
769 if (dhcp->offered_t1_renew != 0xffffffffUL) {
\r
770 /* set renewal period timer */
\r
771 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_bind(): t1 renewal timer %"U32_F" secs\n", dhcp->offered_t1_renew));
\r
772 dhcp->t1_timeout = (dhcp->offered_t1_renew + DHCP_COARSE_TIMER_SECS / 2) / DHCP_COARSE_TIMER_SECS;
\r
773 if (dhcp->t1_timeout == 0) dhcp->t1_timeout = 1;
\r
774 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_bind(): set request timeout %"U32_F" msecs\n", dhcp->offered_t1_renew*1000));
\r
776 /* set renewal period timer */
\r
777 if (dhcp->offered_t2_rebind != 0xffffffffUL) {
\r
778 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_bind(): t2 rebind timer %"U32_F" secs\n", dhcp->offered_t2_rebind));
\r
779 dhcp->t2_timeout = (dhcp->offered_t2_rebind + DHCP_COARSE_TIMER_SECS / 2) / DHCP_COARSE_TIMER_SECS;
\r
780 if (dhcp->t2_timeout == 0) dhcp->t2_timeout = 1;
\r
781 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_bind(): set request timeout %"U32_F" msecs\n", dhcp->offered_t2_rebind*1000));
\r
783 /* copy offered network mask */
\r
784 ip_addr_set(&sn_mask, &dhcp->offered_sn_mask);
\r
786 /* subnet mask not given? */
\r
787 /* TODO: this is not a valid check. what if the network mask is 0? */
\r
788 if (sn_mask.addr == 0) {
\r
789 /* choose a safe subnet mask given the network class */
\r
790 u8_t first_octet = ip4_addr1(&sn_mask);
\r
791 if (first_octet <= 127) sn_mask.addr = htonl(0xff000000);
\r
792 else if (first_octet >= 192) sn_mask.addr = htonl(0xffffff00);
\r
793 else sn_mask.addr = htonl(0xffff0000);
\r
796 ip_addr_set(&gw_addr, &dhcp->offered_gw_addr);
\r
797 /* gateway address not given? */
\r
798 if (gw_addr.addr == 0) {
\r
799 /* copy network address */
\r
800 gw_addr.addr = (dhcp->offered_ip_addr.addr & sn_mask.addr);
\r
801 /* use first host address on network as gateway */
\r
802 gw_addr.addr |= htonl(0x00000001);
\r
805 LWIP_DEBUGF(DHCP_DEBUG | DBG_STATE, ("dhcp_bind(): IP: 0x%08"X32_F"\n", dhcp->offered_ip_addr.addr));
\r
806 netif_set_ipaddr(netif, &dhcp->offered_ip_addr);
\r
807 LWIP_DEBUGF(DHCP_DEBUG | DBG_STATE, ("dhcp_bind(): SN: 0x%08"X32_F"\n", sn_mask.addr));
\r
808 netif_set_netmask(netif, &sn_mask);
\r
809 LWIP_DEBUGF(DHCP_DEBUG | DBG_STATE, ("dhcp_bind(): GW: 0x%08"X32_F"\n", gw_addr.addr));
\r
810 netif_set_gw(netif, &gw_addr);
\r
811 /* bring the interface up */
\r
812 netif_set_up(netif);
\r
813 /* netif is now bound to DHCP leased address */
\r
814 dhcp_set_state(dhcp, DHCP_BOUND);
\r
818 * Renew an existing DHCP lease at the involved DHCP server.
\r
820 * @param netif network interface which must renew its lease
\r
822 err_t dhcp_renew(struct netif *netif)
\r
824 struct dhcp *dhcp = netif->dhcp;
\r
827 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_renew()\n"));
\r
828 dhcp_set_state(dhcp, DHCP_RENEWING);
\r
830 /* create and initialize the DHCP message header */
\r
831 result = dhcp_create_request(netif);
\r
832 if (result == ERR_OK) {
\r
834 dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN);
\r
835 dhcp_option_byte(dhcp, DHCP_REQUEST);
\r
837 dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
\r
838 /* TODO: use netif->mtu in some way */
\r
839 dhcp_option_short(dhcp, 576);
\r
842 dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
\r
843 dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr));
\r
847 dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4);
\r
848 dhcp_option_long(dhcp, ntohl(dhcp->server_ip_addr.addr));
\r
850 /* append DHCP message trailer */
\r
851 dhcp_option_trailer(dhcp);
\r
853 pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
\r
855 udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
\r
856 udp_connect(dhcp->pcb, &dhcp->server_ip_addr, DHCP_SERVER_PORT);
\r
857 udp_send(dhcp->pcb, dhcp->p_out);
\r
858 dhcp_delete_request(netif);
\r
860 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_renew: RENEWING\n"));
\r
862 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_renew: could not allocate DHCP request\n"));
\r
865 /* back-off on retries, but to a maximum of 20 seconds */
\r
866 msecs = dhcp->tries < 10 ? dhcp->tries * 2000 : 20 * 1000;
\r
867 dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
\r
868 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_renew(): set request timeout %"U16_F" msecs\n", msecs));
\r
873 * Rebind with a DHCP server for an existing DHCP lease.
\r
875 * @param netif network interface which must rebind with a DHCP server
\r
877 static err_t dhcp_rebind(struct netif *netif)
\r
879 struct dhcp *dhcp = netif->dhcp;
\r
882 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_rebind()\n"));
\r
883 dhcp_set_state(dhcp, DHCP_REBINDING);
\r
885 /* create and initialize the DHCP message header */
\r
886 result = dhcp_create_request(netif);
\r
887 if (result == ERR_OK)
\r
890 dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN);
\r
891 dhcp_option_byte(dhcp, DHCP_REQUEST);
\r
893 dhcp_option(dhcp, DHCP_OPTION_MAX_MSG_SIZE, DHCP_OPTION_MAX_MSG_SIZE_LEN);
\r
894 dhcp_option_short(dhcp, 576);
\r
897 dhcp_option(dhcp, DHCP_OPTION_REQUESTED_IP, 4);
\r
898 dhcp_option_long(dhcp, ntohl(dhcp->offered_ip_addr.addr));
\r
900 dhcp_option(dhcp, DHCP_OPTION_SERVER_ID, 4);
\r
901 dhcp_option_long(dhcp, ntohl(dhcp->server_ip_addr.addr));
\r
904 dhcp_option_trailer(dhcp);
\r
906 pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
\r
908 /* set remote IP association to any DHCP server */
\r
909 udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
\r
910 udp_connect(dhcp->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
\r
911 /* broadcast to server */
\r
912 udp_sendto(dhcp->pcb, dhcp->p_out, IP_ADDR_BROADCAST, DHCP_SERVER_PORT);
\r
913 dhcp_delete_request(netif);
\r
914 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_rebind: REBINDING\n"));
\r
916 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_rebind: could not allocate DHCP request\n"));
\r
919 msecs = dhcp->tries < 10 ? dhcp->tries * 1000 : 10 * 1000;
\r
920 dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
\r
921 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_rebind(): set request timeout %"U16_F" msecs\n", msecs));
\r
926 * Release a DHCP lease.
\r
928 * @param netif network interface which must release its lease
\r
930 err_t dhcp_release(struct netif *netif)
\r
932 struct dhcp *dhcp = netif->dhcp;
\r
935 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_release()\n"));
\r
937 /* idle DHCP client */
\r
938 dhcp_set_state(dhcp, DHCP_OFF);
\r
939 /* clean old DHCP offer */
\r
940 dhcp->server_ip_addr.addr = 0;
\r
941 dhcp->offered_ip_addr.addr = dhcp->offered_sn_mask.addr = 0;
\r
942 dhcp->offered_gw_addr.addr = dhcp->offered_bc_addr.addr = 0;
\r
943 dhcp->offered_t0_lease = dhcp->offered_t1_renew = dhcp->offered_t2_rebind = 0;
\r
944 dhcp->dns_count = 0;
\r
946 /* create and initialize the DHCP message header */
\r
947 result = dhcp_create_request(netif);
\r
948 if (result == ERR_OK) {
\r
949 dhcp_option(dhcp, DHCP_OPTION_MESSAGE_TYPE, DHCP_OPTION_MESSAGE_TYPE_LEN);
\r
950 dhcp_option_byte(dhcp, DHCP_RELEASE);
\r
952 dhcp_option_trailer(dhcp);
\r
954 pbuf_realloc(dhcp->p_out, sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN + dhcp->options_out_len);
\r
956 udp_bind(dhcp->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
\r
957 udp_connect(dhcp->pcb, &dhcp->server_ip_addr, DHCP_SERVER_PORT);
\r
958 udp_send(dhcp->pcb, dhcp->p_out);
\r
959 dhcp_delete_request(netif);
\r
960 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_release: RELEASED, DHCP_OFF\n"));
\r
962 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_release: could not allocate DHCP request\n"));
\r
965 msecs = dhcp->tries < 10 ? dhcp->tries * 1000 : 10 * 1000;
\r
966 dhcp->request_timeout = (msecs + DHCP_FINE_TIMER_MSECS - 1) / DHCP_FINE_TIMER_MSECS;
\r
967 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | DBG_STATE, ("dhcp_release(): set request timeout %"U16_F" msecs\n", msecs));
\r
968 /* bring the interface down */
\r
969 netif_set_down(netif);
\r
970 /* remove IP address from interface */
\r
971 netif_set_ipaddr(netif, IP_ADDR_ANY);
\r
972 netif_set_gw(netif, IP_ADDR_ANY);
\r
973 netif_set_netmask(netif, IP_ADDR_ANY);
\r
975 /* TODO: netif_down(netif); */
\r
979 * Remove the DHCP client from the interface.
\r
981 * @param netif The network interface to stop DHCP on
\r
983 void dhcp_stop(struct netif *netif)
\r
985 struct dhcp *dhcp = netif->dhcp;
\r
986 LWIP_ASSERT("dhcp_stop: netif != NULL", netif != NULL);
\r
988 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_stop()\n"));
\r
989 /* netif is DHCP configured? */
\r
992 if (dhcp->pcb != NULL)
\r
994 udp_remove(dhcp->pcb);
\r
997 if (dhcp->p != NULL)
\r
999 pbuf_free(dhcp->p);
\r
1002 /* free unfolded reply */
\r
1003 dhcp_free_reply(dhcp);
\r
1004 mem_free((void *)dhcp);
\r
1005 netif->dhcp = NULL;
\r
1010 * Set the DHCP state of a DHCP client.
\r
1012 * If the state changed, reset the number of tries.
\r
1014 * TODO: we might also want to reset the timeout here?
\r
1016 static void dhcp_set_state(struct dhcp *dhcp, u8_t new_state)
\r
1018 if (new_state != dhcp->state)
\r
1020 dhcp->state = new_state;
\r
1026 * Concatenate an option type and length field to the outgoing
\r
1030 static void dhcp_option(struct dhcp *dhcp, u8_t option_type, u8_t option_len)
\r
1032 LWIP_ASSERT("dhcp_option_short: dhcp->options_out_len + 2 + option_len <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 2 + option_len <= DHCP_OPTIONS_LEN);
\r
1033 dhcp->msg_out->options[dhcp->options_out_len++] = option_type;
\r
1034 dhcp->msg_out->options[dhcp->options_out_len++] = option_len;
\r
1037 * Concatenate a single byte to the outgoing DHCP message.
\r
1040 static void dhcp_option_byte(struct dhcp *dhcp, u8_t value)
\r
1042 LWIP_ASSERT("dhcp_option_short: dhcp->options_out_len < DHCP_OPTIONS_LEN", dhcp->options_out_len < DHCP_OPTIONS_LEN);
\r
1043 dhcp->msg_out->options[dhcp->options_out_len++] = value;
\r
1045 static void dhcp_option_short(struct dhcp *dhcp, u16_t value)
\r
1047 LWIP_ASSERT("dhcp_option_short: dhcp->options_out_len + 2 <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 2 <= DHCP_OPTIONS_LEN);
\r
1048 dhcp->msg_out->options[dhcp->options_out_len++] = (value & 0xff00U) >> 8;
\r
1049 dhcp->msg_out->options[dhcp->options_out_len++] = value & 0x00ffU;
\r
1051 static void dhcp_option_long(struct dhcp *dhcp, u32_t value)
\r
1053 LWIP_ASSERT("dhcp_option_long: dhcp->options_out_len + 4 <= DHCP_OPTIONS_LEN", dhcp->options_out_len + 4 <= DHCP_OPTIONS_LEN);
\r
1054 dhcp->msg_out->options[dhcp->options_out_len++] = (value & 0xff000000UL) >> 24;
\r
1055 dhcp->msg_out->options[dhcp->options_out_len++] = (value & 0x00ff0000UL) >> 16;
\r
1056 dhcp->msg_out->options[dhcp->options_out_len++] = (value & 0x0000ff00UL) >> 8;
\r
1057 dhcp->msg_out->options[dhcp->options_out_len++] = (value & 0x000000ffUL);
\r
1061 * Extract the DHCP message and the DHCP options.
\r
1063 * Extract the DHCP message and the DHCP options, each into a contiguous
\r
1064 * piece of memory. As a DHCP message is variable sized by its options,
\r
1065 * and also allows overriding some fields for options, the easy approach
\r
1066 * is to first unfold the options into a conitguous piece of memory, and
\r
1067 * use that further on.
\r
1070 static err_t dhcp_unfold_reply(struct dhcp *dhcp)
\r
1072 struct pbuf *p = dhcp->p;
\r
1076 LWIP_ASSERT("dhcp->p != NULL", dhcp->p != NULL);
\r
1077 /* free any left-overs from previous unfolds */
\r
1078 dhcp_free_reply(dhcp);
\r
1079 /* options present? */
\r
1080 if (dhcp->p->tot_len > (sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN))
\r
1082 dhcp->options_in_len = dhcp->p->tot_len - (sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN);
\r
1083 dhcp->options_in = mem_malloc(dhcp->options_in_len);
\r
1084 if (dhcp->options_in == NULL)
\r
1086 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_unfold_reply(): could not allocate dhcp->options\n"));
\r
1090 dhcp->msg_in = mem_malloc(sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN);
\r
1091 if (dhcp->msg_in == NULL)
\r
1093 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_unfold_reply(): could not allocate dhcp->msg_in\n"));
\r
1094 mem_free((void *)dhcp->options_in);
\r
1095 dhcp->options_in = NULL;
\r
1099 ptr = (u8_t *)dhcp->msg_in;
\r
1100 /* proceed through struct dhcp_msg */
\r
1101 for (i = 0; i < sizeof(struct dhcp_msg) - DHCP_OPTIONS_LEN; i++)
\r
1103 *ptr++ = ((u8_t *)p->payload)[j++];
\r
1104 /* reached end of pbuf? */
\r
1107 /* proceed to next pbuf in chain */
\r
1112 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_unfold_reply(): copied %"U16_F" bytes into dhcp->msg_in[]\n", i));
\r
1113 if (dhcp->options_in != NULL) {
\r
1114 ptr = (u8_t *)dhcp->options_in;
\r
1115 /* proceed through options */
\r
1116 for (i = 0; i < dhcp->options_in_len; i++) {
\r
1117 *ptr++ = ((u8_t *)p->payload)[j++];
\r
1118 /* reached end of pbuf? */
\r
1119 if (j == p->len) {
\r
1120 /* proceed to next pbuf in chain */
\r
1125 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("dhcp_unfold_reply(): copied %"U16_F" bytes to dhcp->options_in[]\n", i));
\r
1131 * Free the incoming DHCP message including contiguous copy of
\r
1132 * its DHCP options.
\r
1135 static void dhcp_free_reply(struct dhcp *dhcp)
\r
1137 if (dhcp->msg_in != NULL) {
\r
1138 mem_free((void *)dhcp->msg_in);
\r
1139 dhcp->msg_in = NULL;
\r
1141 if (dhcp->options_in) {
\r
1142 mem_free((void *)dhcp->options_in);
\r
1143 dhcp->options_in = NULL;
\r
1144 dhcp->options_in_len = 0;
\r
1146 LWIP_DEBUGF(DHCP_DEBUG, ("dhcp_free_reply(): free'd\n"));
\r
1151 * If an incoming DHCP message is in response to us, then trigger the state machine
\r
1153 static void dhcp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port)
\r
1155 struct netif *netif = (struct netif *)arg;
\r
1156 struct dhcp *dhcp = netif->dhcp;
\r
1157 struct dhcp_msg *reply_msg = (struct dhcp_msg *)p->payload;
\r
1158 u8_t *options_ptr;
\r
1161 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 3, ("dhcp_recv(pbuf = %p) from DHCP server %"U16_F".%"U16_F".%"U16_F".%"U16_F" port %"U16_F"\n", (void*)p,
\r
1162 (u16_t)(ntohl(addr->addr) >> 24 & 0xff), (u16_t)(ntohl(addr->addr) >> 16 & 0xff),
\r
1163 (u16_t)(ntohl(addr->addr) >> 8 & 0xff), (u16_t)(ntohl(addr->addr) & 0xff), port));
\r
1164 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("pbuf->len = %"U16_F"\n", p->len));
\r
1165 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("pbuf->tot_len = %"U16_F"\n", p->tot_len));
\r
1166 /* prevent warnings about unused arguments */
\r
1167 (void)pcb; (void)addr; (void)port;
\r
1169 /* TODO: check packet length before reading them */
\r
1170 if (reply_msg->op != DHCP_BOOTREPLY) {
\r
1171 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 1, ("not a DHCP reply message, but type %"U16_F"\n", (u16_t)reply_msg->op));
\r
1176 /* iterate through hardware address and match against DHCP message */
\r
1177 for (i = 0; i < netif->hwaddr_len; i++) {
\r
1178 if (netif->hwaddr[i] != reply_msg->chaddr[i]) {
\r
1179 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("netif->hwaddr[%"U16_F"]==%02"X16_F" != reply_msg->chaddr[%"U16_F"]==%02"X16_F"\n",
\r
1180 (u16_t)i, (u16_t)netif->hwaddr[i], (u16_t)i, (u16_t)reply_msg->chaddr[i]));
\r
1186 /* match transaction ID against what we expected */
\r
1187 if (ntohl(reply_msg->xid) != dhcp->xid) {
\r
1188 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("transaction id mismatch\n"));
\r
1193 /* option fields could be unfold? */
\r
1194 if (dhcp_unfold_reply(dhcp) != ERR_OK) {
\r
1195 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("problem unfolding DHCP message - too short on memory?\n"));
\r
1201 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("searching DHCP_OPTION_MESSAGE_TYPE\n"));
\r
1202 /* obtain pointer to DHCP message type */
\r
1203 options_ptr = dhcp_get_option_ptr(dhcp, DHCP_OPTION_MESSAGE_TYPE);
\r
1204 if (options_ptr == NULL) {
\r
1205 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 1, ("DHCP_OPTION_MESSAGE_TYPE option not found\n"));
\r
1211 /* read DHCP message type */
\r
1212 msg_type = dhcp_get_option_byte(options_ptr + 2);
\r
1213 /* message type is DHCP ACK? */
\r
1214 if (msg_type == DHCP_ACK) {
\r
1215 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 1, ("DHCP_ACK received\n"));
\r
1216 /* in requesting state? */
\r
1217 if (dhcp->state == DHCP_REQUESTING) {
\r
1218 dhcp_handle_ack(netif);
\r
1219 dhcp->request_timeout = 0;
\r
1220 #if DHCP_DOES_ARP_CHECK
\r
1221 /* check if the acknowledged lease address is already in use */
\r
1222 dhcp_check(netif);
\r
1224 /* bind interface to the acknowledged lease address */
\r
1228 /* already bound to the given lease address? */
\r
1229 else if ((dhcp->state == DHCP_REBOOTING) || (dhcp->state == DHCP_REBINDING) || (dhcp->state == DHCP_RENEWING)) {
\r
1230 dhcp->request_timeout = 0;
\r
1234 /* received a DHCP_NAK in appropriate state? */
\r
1235 else if ((msg_type == DHCP_NAK) &&
\r
1236 ((dhcp->state == DHCP_REBOOTING) || (dhcp->state == DHCP_REQUESTING) ||
\r
1237 (dhcp->state == DHCP_REBINDING) || (dhcp->state == DHCP_RENEWING ))) {
\r
1238 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 1, ("DHCP_NAK received\n"));
\r
1239 dhcp->request_timeout = 0;
\r
1240 dhcp_handle_nak(netif);
\r
1242 /* received a DHCP_OFFER in DHCP_SELECTING state? */
\r
1243 else if ((msg_type == DHCP_OFFER) && (dhcp->state == DHCP_SELECTING)) {
\r
1244 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 1, ("DHCP_OFFER received in DHCP_SELECTING state\n"));
\r
1245 dhcp->request_timeout = 0;
\r
1246 /* remember offered lease */
\r
1247 dhcp_handle_offer(netif);
\r
1254 static err_t dhcp_create_request(struct netif *netif)
\r
1256 struct dhcp *dhcp = netif->dhcp;
\r
1258 LWIP_ASSERT("dhcp_create_request: dhcp->p_out == NULL", dhcp->p_out == NULL);
\r
1259 LWIP_ASSERT("dhcp_create_request: dhcp->msg_out == NULL", dhcp->msg_out == NULL);
\r
1260 dhcp->p_out = pbuf_alloc(PBUF_TRANSPORT, sizeof(struct dhcp_msg), PBUF_RAM);
\r
1261 if (dhcp->p_out == NULL) {
\r
1262 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("dhcp_create_request(): could not allocate pbuf\n"));
\r
1265 /* give unique transaction identifier to this request */
\r
1266 dhcp->xid = xid++;
\r
1268 dhcp->msg_out = (struct dhcp_msg *)dhcp->p_out->payload;
\r
1270 dhcp->msg_out->op = DHCP_BOOTREQUEST;
\r
1271 /* TODO: make link layer independent */
\r
1272 dhcp->msg_out->htype = DHCP_HTYPE_ETH;
\r
1273 /* TODO: make link layer independent */
\r
1274 dhcp->msg_out->hlen = DHCP_HLEN_ETH;
\r
1275 dhcp->msg_out->hops = 0;
\r
1276 dhcp->msg_out->xid = htonl(dhcp->xid);
\r
1277 dhcp->msg_out->secs = 0;
\r
1278 dhcp->msg_out->flags = 0;
\r
1279 dhcp->msg_out->ciaddr.addr = netif->ip_addr.addr;
\r
1280 dhcp->msg_out->yiaddr.addr = 0;
\r
1281 dhcp->msg_out->siaddr.addr = 0;
\r
1282 dhcp->msg_out->giaddr.addr = 0;
\r
1283 for (i = 0; i < DHCP_CHADDR_LEN; i++) {
\r
1284 /* copy netif hardware address, pad with zeroes */
\r
1285 dhcp->msg_out->chaddr[i] = (i < netif->hwaddr_len) ? netif->hwaddr[i] : 0/* pad byte*/;
\r
1287 for (i = 0; i < DHCP_SNAME_LEN; i++) dhcp->msg_out->sname[i] = 0;
\r
1288 for (i = 0; i < DHCP_FILE_LEN; i++) dhcp->msg_out->file[i] = 0;
\r
1289 dhcp->msg_out->cookie = htonl(0x63825363UL);
\r
1290 dhcp->options_out_len = 0;
\r
1291 /* fill options field with an incrementing array (for debugging purposes) */
\r
1292 for (i = 0; i < DHCP_OPTIONS_LEN; i++) dhcp->msg_out->options[i] = i;
\r
1296 static void dhcp_delete_request(struct netif *netif)
\r
1298 struct dhcp *dhcp = netif->dhcp;
\r
1299 LWIP_ASSERT("dhcp_free_msg: dhcp->p_out != NULL", dhcp->p_out != NULL);
\r
1300 LWIP_ASSERT("dhcp_free_msg: dhcp->msg_out != NULL", dhcp->msg_out != NULL);
\r
1301 pbuf_free(dhcp->p_out);
\r
1302 dhcp->p_out = NULL;
\r
1303 dhcp->msg_out = NULL;
\r
1307 * Add a DHCP message trailer
\r
1309 * Adds the END option to the DHCP message, and if
\r
1310 * necessary, up to three padding bytes.
\r
1313 static void dhcp_option_trailer(struct dhcp *dhcp)
\r
1315 LWIP_ASSERT("dhcp_option_trailer: dhcp->msg_out != NULL\n", dhcp->msg_out != NULL);
\r
1316 LWIP_ASSERT("dhcp_option_trailer: dhcp->options_out_len < DHCP_OPTIONS_LEN\n", dhcp->options_out_len < DHCP_OPTIONS_LEN);
\r
1317 dhcp->msg_out->options[dhcp->options_out_len++] = DHCP_OPTION_END;
\r
1318 /* packet is too small, or not 4 byte aligned? */
\r
1319 while ((dhcp->options_out_len < DHCP_MIN_OPTIONS_LEN) || (dhcp->options_out_len & 3)) {
\r
1320 /* 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)); */
\r
1321 LWIP_ASSERT("dhcp_option_trailer: dhcp->options_out_len < DHCP_OPTIONS_LEN\n", dhcp->options_out_len < DHCP_OPTIONS_LEN);
\r
1322 /* add a fill/padding byte */
\r
1323 dhcp->msg_out->options[dhcp->options_out_len++] = 0;
\r
1328 * Find the offset of a DHCP option inside the DHCP message.
\r
1330 * @param client DHCP client
\r
1331 * @param option_type
\r
1333 * @return a byte offset into the UDP message where the option was found, or
\r
1334 * zero if the given option was not found.
\r
1336 static u8_t *dhcp_get_option_ptr(struct dhcp *dhcp, u8_t option_type)
\r
1338 u8_t overload = DHCP_OVERLOAD_NONE;
\r
1340 /* options available? */
\r
1341 if ((dhcp->options_in != NULL) && (dhcp->options_in_len > 0)) {
\r
1342 /* start with options field */
\r
1343 u8_t *options = (u8_t *)dhcp->options_in;
\r
1345 /* at least 1 byte to read and no end marker, then at least 3 bytes to read? */
\r
1346 while ((offset < dhcp->options_in_len) && (options[offset] != DHCP_OPTION_END)) {
\r
1347 /* LWIP_DEBUGF(DHCP_DEBUG, ("msg_offset=%"U16_F", q->len=%"U16_F, msg_offset, q->len)); */
\r
1348 /* are the sname and/or file field overloaded with options? */
\r
1349 if (options[offset] == DHCP_OPTION_OVERLOAD) {
\r
1350 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 2, ("overloaded message detected\n"));
\r
1351 /* skip option type and length */
\r
1353 overload = options[offset++];
\r
1355 /* requested option found */
\r
1356 else if (options[offset] == option_type) {
\r
1357 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("option found at offset %"U16_F" in options\n", offset));
\r
1358 return &options[offset];
\r
1361 LWIP_DEBUGF(DHCP_DEBUG, ("skipping option %"U16_F" in options\n", options[offset]));
\r
1362 /* skip option type */
\r
1364 /* skip option length, and then length bytes */
\r
1365 offset += 1 + options[offset];
\r
1368 /* is this an overloaded message? */
\r
1369 if (overload != DHCP_OVERLOAD_NONE) {
\r
1371 if (overload == DHCP_OVERLOAD_FILE) {
\r
1372 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 1, ("overloaded file field\n"));
\r
1373 options = (u8_t *)&dhcp->msg_in->file;
\r
1374 field_len = DHCP_FILE_LEN;
\r
1375 } else if (overload == DHCP_OVERLOAD_SNAME) {
\r
1376 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 1, ("overloaded sname field\n"));
\r
1377 options = (u8_t *)&dhcp->msg_in->sname;
\r
1378 field_len = DHCP_SNAME_LEN;
\r
1379 /* TODO: check if else if () is necessary */
\r
1381 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE | 1, ("overloaded sname and file field\n"));
\r
1382 options = (u8_t *)&dhcp->msg_in->sname;
\r
1383 field_len = DHCP_FILE_LEN + DHCP_SNAME_LEN;
\r
1387 /* at least 1 byte to read and no end marker */
\r
1388 while ((offset < field_len) && (options[offset] != DHCP_OPTION_END)) {
\r
1389 if (options[offset] == option_type) {
\r
1390 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("option found at offset=%"U16_F"\n", offset));
\r
1391 return &options[offset];
\r
1394 LWIP_DEBUGF(DHCP_DEBUG | DBG_TRACE, ("skipping option %"U16_F"\n", options[offset]));
\r
1395 /* skip option type */
\r
1397 offset += 1 + options[offset];
\r
1406 * Return the byte of DHCP option data.
\r
1408 * @param client DHCP client.
\r
1409 * @param ptr pointer obtained by dhcp_get_option_ptr().
\r
1411 * @return byte value at the given address.
\r
1413 static u8_t dhcp_get_option_byte(u8_t *ptr)
\r
1415 LWIP_DEBUGF(DHCP_DEBUG, ("option byte value=%"U16_F"\n", (u16_t)(*ptr)));
\r
1420 * Return the 16-bit value of DHCP option data.
\r
1422 * @param client DHCP client.
\r
1423 * @param ptr pointer obtained by dhcp_get_option_ptr().
\r
1425 * @return byte value at the given address.
\r
1427 static u16_t dhcp_get_option_short(u8_t *ptr)
\r
1430 value = *ptr++ << 8;
\r
1432 LWIP_DEBUGF(DHCP_DEBUG, ("option short value=%"U16_F"\n", value));
\r
1437 * Return the 32-bit value of DHCP option data.
\r
1439 * @param client DHCP client.
\r
1440 * @param ptr pointer obtained by dhcp_get_option_ptr().
\r
1442 * @return byte value at the given address.
\r
1444 static u32_t dhcp_get_option_long(u8_t *ptr)
\r
1447 value = (u32_t)(*ptr++) << 24;
\r
1448 value |= (u32_t)(*ptr++) << 16;
\r
1449 value |= (u32_t)(*ptr++) << 8;
\r
1450 value |= (u32_t)(*ptr++);
\r
1451 LWIP_DEBUGF(DHCP_DEBUG, ("option long value=%"U32_F"\n", value));
\r
1455 #endif /* LWIP_DHCP */
\r