lib/liblwip/include/lwip/dhcp.h

   1 /** @file
   2  */
   3
   4 #ifndef __LWIP_DHCP_H__
   5 #define __LWIP_DHCP_H__
   6
   7 #include "lwip/opt.h"
   8
   9 #if LWIP_DHCP /* don't build if not configured for use in lwipopts.h */
  10
  11 #include "lwip/netif.h"
  12 #include "lwip/udp.h"
  13
  14 #ifdef __cplusplus
  15 extern "C" {
  16 #endif
  17
  18 /** period (in seconds) of the application calling dhcp_coarse_tmr() */
  19 #define DHCP_COARSE_TIMER_SECS 60
  20 /** period (in milliseconds) of the application calling dhcp_coarse_tmr() */
  21 #define DHCP_COARSE_TIMER_MSECS (DHCP_COARSE_TIMER_SECS * 1000UL)
  22 /** period (in milliseconds) of the application calling dhcp_fine_tmr() */
  23 #define DHCP_FINE_TIMER_MSECS 500
  24
  25 #define DHCP_CHADDR_LEN 16U
  26 #define DHCP_SNAME_LEN  64U
  27 #define DHCP_FILE_LEN   128U
  28
  29 struct dhcp
  30 {
  31   /** transaction identifier of last sent request */
  32   u32_t xid;
  33   /** our connection to the DHCP server */
  34   struct udp_pcb *pcb;
  35   /** incoming msg */
  36   struct dhcp_msg *msg_in;
  37   /** current DHCP state machine state */
  38   u8_t state;
  39   /** retries of current request */
  40   u8_t tries;
  41 #if LWIP_DHCP_AUTOIP_COOP
  42   u8_t autoip_coop_state;
  43 #endif
  44   u8_t subnet_mask_given;
  45
  46   struct pbuf *p_out; /* pbuf of outcoming msg */
  47   struct dhcp_msg *msg_out; /* outgoing msg */
  48   u16_t options_out_len; /* outgoing msg options length */
  49   u16_t request_timeout; /* #ticks with period DHCP_FINE_TIMER_SECS for request timeout */
  50   u16_t t1_timeout;  /* #ticks with period DHCP_COARSE_TIMER_SECS for renewal time */
  51   u16_t t2_timeout;  /* #ticks with period DHCP_COARSE_TIMER_SECS for rebind time */
  52   ip_addr_t server_ip_addr; /* dhcp server address that offered this lease */
  53   ip_addr_t offered_ip_addr;
  54   ip_addr_t offered_sn_mask;
  55   ip_addr_t offered_gw_addr;
  56
  57   u32_t offered_t0_lease; /* lease period (in seconds) */
  58   u32_t offered_t1_renew; /* recommended renew time (usually 50% of lease period) */
  59   u32_t offered_t2_rebind; /* recommended rebind time (usually 66% of lease period)  */
  60   /* @todo: LWIP_DHCP_BOOTP_FILE configuration option?
  61      integrate with possible TFTP-client for booting? */
  62 #if LWIP_DHCP_BOOTP_FILE
  63   ip_addr_t offered_si_addr;
  64   char boot_file_name[DHCP_FILE_LEN];
  65 #endif /* LWIP_DHCP_BOOTPFILE */
  66 };
  67
  68 /* MUST be compiled with "pack structs" or equivalent! */
  69 #ifdef PACK_STRUCT_USE_INCLUDES
  70 #  include "arch/bpstruct.h"
  71 #endif
  72 PACK_STRUCT_BEGIN
  73 /** minimum set of fields of any DHCP message */
  74 struct dhcp_msg
  75 {
  76   PACK_STRUCT_FIELD(u8_t op);
  77   PACK_STRUCT_FIELD(u8_t htype);
  78   PACK_STRUCT_FIELD(u8_t hlen);
  79   PACK_STRUCT_FIELD(u8_t hops);
  80   PACK_STRUCT_FIELD(u32_t xid);
  81   PACK_STRUCT_FIELD(u16_t secs);
  82   PACK_STRUCT_FIELD(u16_t flags);
  83   PACK_STRUCT_FIELD(ip_addr_p_t ciaddr);
  84   PACK_STRUCT_FIELD(ip_addr_p_t yiaddr);
  85   PACK_STRUCT_FIELD(ip_addr_p_t siaddr);
  86   PACK_STRUCT_FIELD(ip_addr_p_t giaddr);
  87   PACK_STRUCT_FIELD(u8_t chaddr[DHCP_CHADDR_LEN]);
  88   PACK_STRUCT_FIELD(u8_t sname[DHCP_SNAME_LEN]);
  89   PACK_STRUCT_FIELD(u8_t file[DHCP_FILE_LEN]);
  90   PACK_STRUCT_FIELD(u32_t cookie);
  91 #define DHCP_MIN_OPTIONS_LEN 68U
  92 /** make sure user does not configure this too small */
  93 #if ((defined(DHCP_OPTIONS_LEN)) && (DHCP_OPTIONS_LEN < DHCP_MIN_OPTIONS_LEN))
  94 #  undef DHCP_OPTIONS_LEN
  95 #endif
  96 /** allow this to be configured in lwipopts.h, but not too small */
  97 #if (!defined(DHCP_OPTIONS_LEN))
  98 /** set this to be sufficient for your options in outgoing DHCP msgs */
  99 #  define DHCP_OPTIONS_LEN DHCP_MIN_OPTIONS_LEN
 100 #endif
 101   PACK_STRUCT_FIELD(u8_t options[DHCP_OPTIONS_LEN]);
 102 } PACK_STRUCT_STRUCT;
 103 PACK_STRUCT_END
 104 #ifdef PACK_STRUCT_USE_INCLUDES
 105 #  include "arch/epstruct.h"
 106 #endif
 107
 108 void dhcp_set_struct(struct netif *netif, struct dhcp *dhcp);
 109 /** start DHCP configuration */
 110 err_t dhcp_start(struct netif *netif);
 111 /** enforce early lease renewal (not needed normally)*/
 112 err_t dhcp_renew(struct netif *netif);
 113 /** release the DHCP lease, usually called before dhcp_stop()*/
 114 err_t dhcp_release(struct netif *netif);
 115 /** stop DHCP configuration */
 116 void dhcp_stop(struct netif *netif);
 117 /** inform server of our manual IP address */
 118 void dhcp_inform(struct netif *netif);
 119 /** Handle a possible change in the network configuration */
 120 void dhcp_network_changed(struct netif *netif);
 121
 122 /** if enabled, check whether the offered IP address is not in use, using ARP */
 123 #if DHCP_DOES_ARP_CHECK
 124 void dhcp_arp_reply(struct netif *netif, ip_addr_t *addr);
 125 #endif
 126
 127 /** to be called every minute */
 128 void dhcp_coarse_tmr(void);
 129 /** to be called every half second */
 130 void dhcp_fine_tmr(void);
 131
 132 /** DHCP message item offsets and length */
 133 #define DHCP_OP_OFS       0
 134 #define DHCP_HTYPE_OFS    1
 135 #define DHCP_HLEN_OFS     2
 136 #define DHCP_HOPS_OFS     3
 137 #define DHCP_XID_OFS      4
 138 #define DHCP_SECS_OFS     8
 139 #define DHCP_FLAGS_OFS    10
 140 #define DHCP_CIADDR_OFS   12
 141 #define DHCP_YIADDR_OFS   16
 142 #define DHCP_SIADDR_OFS   20
 143 #define DHCP_GIADDR_OFS   24
 144 #define DHCP_CHADDR_OFS   28
 145 #define DHCP_SNAME_OFS    44
 146 #define DHCP_FILE_OFS     108
 147 #define DHCP_MSG_LEN      236
 148
 149 #define DHCP_COOKIE_OFS   DHCP_MSG_LEN
 150 #define DHCP_OPTIONS_OFS  (DHCP_MSG_LEN + 4)
 151
 152 #define DHCP_CLIENT_PORT  68
 153 #define DHCP_SERVER_PORT  67
 154
 155 /** DHCP client states */
 156 #define DHCP_OFF          0
 157 #define DHCP_REQUESTING   1
 158 #define DHCP_INIT         2
 159 #define DHCP_REBOOTING    3
 160 #define DHCP_REBINDING    4
 161 #define DHCP_RENEWING     5
 162 #define DHCP_SELECTING    6
 163 #define DHCP_INFORMING    7
 164 #define DHCP_CHECKING     8
 165 #define DHCP_PERMANENT    9
 166 #define DHCP_BOUND        10
 167 /** not yet implemented #define DHCP_RELEASING 11 */
 168 #define DHCP_BACKING_OFF  12
 169
 170 /** AUTOIP cooperatation flags */
 171 #define DHCP_AUTOIP_COOP_STATE_OFF  0
 172 #define DHCP_AUTOIP_COOP_STATE_ON   1
 173
 174 #define DHCP_BOOTREQUEST  1
 175 #define DHCP_BOOTREPLY    2
 176
 177 /** DHCP message types */
 178 #define DHCP_DISCOVER 1
 179 #define DHCP_OFFER    2
 180 #define DHCP_REQUEST  3
 181 #define DHCP_DECLINE  4
 182 #define DHCP_ACK      5
 183 #define DHCP_NAK      6
 184 #define DHCP_RELEASE  7
 185 #define DHCP_INFORM   8
 186
 187 /** DHCP hardware type, currently only ethernet is supported */
 188 #define DHCP_HTYPE_ETH 1
 189
 190 #define DHCP_MAGIC_COOKIE 0x63825363UL
 191
 192 /* This is a list of options for BOOTP and DHCP, see RFC 2132 for descriptions */
 193
 194 /** BootP options */
 195 #define DHCP_OPTION_PAD 0
 196 #define DHCP_OPTION_SUBNET_MASK 1 /* RFC 2132 3.3 */
 197 #define DHCP_OPTION_ROUTER 3
 198 #define DHCP_OPTION_DNS_SERVER 6
 199 #define DHCP_OPTION_HOSTNAME 12
 200 #define DHCP_OPTION_IP_TTL 23
 201 #define DHCP_OPTION_MTU 26
 202 #define DHCP_OPTION_BROADCAST 28
 203 #define DHCP_OPTION_TCP_TTL 37
 204 #define DHCP_OPTION_END 255
 205
 206 /** DHCP options */
 207 #define DHCP_OPTION_REQUESTED_IP 50 /* RFC 2132 9.1, requested IP address */
 208 #define DHCP_OPTION_LEASE_TIME 51 /* RFC 2132 9.2, time in seconds, in 4 bytes */
 209 #define DHCP_OPTION_OVERLOAD 52 /* RFC2132 9.3, use file and/or sname field for options */
 210
 211 #define DHCP_OPTION_MESSAGE_TYPE 53 /* RFC 2132 9.6, important for DHCP */
 212 #define DHCP_OPTION_MESSAGE_TYPE_LEN 1
 213
 214 #define DHCP_OPTION_SERVER_ID 54 /* RFC 2132 9.7, server IP address */
 215 #define DHCP_OPTION_PARAMETER_REQUEST_LIST 55 /* RFC 2132 9.8, requested option types */
 216
 217 #define DHCP_OPTION_MAX_MSG_SIZE 57 /* RFC 2132 9.10, message size accepted >= 576 */
 218 #define DHCP_OPTION_MAX_MSG_SIZE_LEN 2
 219
 220 #define DHCP_OPTION_T1 58 /* T1 renewal time */
 221 #define DHCP_OPTION_T2 59 /* T2 rebinding time */
 222 #define DHCP_OPTION_US 60
 223 #define DHCP_OPTION_CLIENT_ID 61
 224 #define DHCP_OPTION_TFTP_SERVERNAME 66
 225 #define DHCP_OPTION_BOOTFILE 67
 226
 227 /** possible combinations of overloading the file and sname fields with options */
 228 #define DHCP_OVERLOAD_NONE 0
 229 #define DHCP_OVERLOAD_FILE 1
 230 #define DHCP_OVERLOAD_SNAME  2
 231 #define DHCP_OVERLOAD_SNAME_FILE 3
 232
 233 #ifdef __cplusplus
 234 }
 235 #endif
 236
 237 #endif /* LWIP_DHCP */
 238
 239 #endif /*__LWIP_DHCP_H__*/