lib/liblwip/include/lwip/udp.h

   1 /*
   2  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without modification,
   6  * are permitted provided that the following conditions are met:
   7  *
   8  * 1. Redistributions of source code must retain the above copyright notice,
   9  *    this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright notice,
  11  *    this list of conditions and the following disclaimer in the documentation
  12  *    and/or other materials provided with the distribution.
  13  * 3. The name of the author may not be used to endorse or promote products
  14  *    derived from this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
  17  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  18  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  19  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
  21  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  22  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  24  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
  25  * OF SUCH DAMAGE.
  26  *
  27  * This file is part of the lwIP TCP/IP stack.
  28  *
  29  * Author: Adam Dunkels <adam@sics.se>
  30  *
  31  */
  32 #ifndef __LWIP_UDP_H__
  33 #define __LWIP_UDP_H__
  34
  35 #include "lwip/opt.h"
  36
  37 #if LWIP_UDP /* don't build if not configured for use in lwipopts.h */
  38
  39 #include "lwip/pbuf.h"
  40 #include "lwip/netif.h"
  41 #include "lwip/ip_addr.h"
  42 #include "lwip/ip.h"
  43
  44 #ifdef __cplusplus
  45 extern "C" {
  46 #endif
  47
  48 #define UDP_HLEN 8
  49
  50 /* Fields are (of course) in network byte order. */
  51 #ifdef PACK_STRUCT_USE_INCLUDES
  52 #  include "arch/bpstruct.h"
  53 #endif
  54 PACK_STRUCT_BEGIN
  55 struct udp_hdr {
  56   PACK_STRUCT_FIELD(u16_t src);
  57   PACK_STRUCT_FIELD(u16_t dest);  /* src/dest UDP ports */
  58   PACK_STRUCT_FIELD(u16_t len);
  59   PACK_STRUCT_FIELD(u16_t chksum);
  60 } PACK_STRUCT_STRUCT;
  61 PACK_STRUCT_END
  62 #ifdef PACK_STRUCT_USE_INCLUDES
  63 #  include "arch/epstruct.h"
  64 #endif
  65
  66 #define UDP_FLAGS_NOCHKSUM       0x01U
  67 #define UDP_FLAGS_UDPLITE        0x02U
  68 #define UDP_FLAGS_CONNECTED      0x04U
  69 #define UDP_FLAGS_MULTICAST_LOOP 0x08U
  70
  71 struct udp_pcb;
  72
  73 /** Function prototype for udp pcb receive callback functions
  74  * addr and port are in same byte order as in the pcb
  75  * The callback is responsible for freeing the pbuf
  76  * if it's not used any more.
  77  *
  78  * ATTENTION: Be aware that 'addr' points into the pbuf 'p' so freeing this pbuf
  79  *            makes 'addr' invalid, too.
  80  *
  81  * @param arg user supplied argument (udp_pcb.recv_arg)
  82  * @param pcb the udp_pcb which received data
  83  * @param p the packet buffer that was received
  84  * @param addr the remote IP address from which the packet was received
  85  * @param port the remote port from which the packet was received
  86  */
  87 typedef void (*udp_recv_fn)(void *arg, struct udp_pcb *pcb, struct pbuf *p,
  88     ip_addr_t *addr, u16_t port);
  89
  90
  91 struct udp_pcb {
  92 /* Common members of all PCB types */
  93   IP_PCB;
  94
  95 /* Protocol specific PCB members */
  96
  97   struct udp_pcb *next;
  98
  99   u8_t flags;
 100   /** ports are in host byte order */
 101   u16_t local_port, remote_port;
 102
 103 #if LWIP_IGMP
 104   /** outgoing network interface for multicast packets */
 105   ip_addr_t multicast_ip;
 106 #endif /* LWIP_IGMP */
 107
 108 #if LWIP_UDPLITE
 109   /** used for UDP_LITE only */
 110   u16_t chksum_len_rx, chksum_len_tx;
 111 #endif /* LWIP_UDPLITE */
 112
 113   /** receive callback function */
 114   udp_recv_fn recv;
 115   /** user-supplied argument for the recv callback */
 116   void *recv_arg;
 117 };
 118 /* udp_pcbs export for exernal reference (e.g. SNMP agent) */
 119 extern struct udp_pcb *udp_pcbs;
 120
 121 /* The following functions is the application layer interface to the
 122    UDP code. */
 123 struct udp_pcb * udp_new        (void);
 124 void             udp_remove     (struct udp_pcb *pcb);
 125 err_t            udp_bind       (struct udp_pcb *pcb, ip_addr_t *ipaddr,
 126                                  u16_t port);
 127 err_t            udp_connect    (struct udp_pcb *pcb, ip_addr_t *ipaddr,
 128                                  u16_t port);
 129 void             udp_disconnect (struct udp_pcb *pcb);
 130 void             udp_recv       (struct udp_pcb *pcb, udp_recv_fn recv,
 131                                  void *recv_arg);
 132 err_t            udp_sendto_if  (struct udp_pcb *pcb, struct pbuf *p,
 133                                  ip_addr_t *dst_ip, u16_t dst_port,
 134                                  struct netif *netif);
 135 err_t            udp_sendto     (struct udp_pcb *pcb, struct pbuf *p,
 136                                  ip_addr_t *dst_ip, u16_t dst_port);
 137 err_t            udp_send       (struct udp_pcb *pcb, struct pbuf *p);
 138
 139 #if LWIP_CHECKSUM_ON_COPY
 140 err_t            udp_sendto_if_chksum(struct udp_pcb *pcb, struct pbuf *p,
 141                                  ip_addr_t *dst_ip, u16_t dst_port,
 142                                  struct netif *netif, u8_t have_chksum,
 143                                  u16_t chksum);
 144 err_t            udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p,
 145                                  ip_addr_t *dst_ip, u16_t dst_port,
 146                                  u8_t have_chksum, u16_t chksum);
 147 err_t            udp_send_chksum(struct udp_pcb *pcb, struct pbuf *p,
 148                                  u8_t have_chksum, u16_t chksum);
 149 #endif /* LWIP_CHECKSUM_ON_COPY */
 150
 151 #define          udp_flags(pcb) ((pcb)->flags)
 152 #define          udp_setflags(pcb, f)  ((pcb)->flags = (f))
 153
 154 /* The following functions are the lower layer interface to UDP. */
 155 void             udp_input      (struct pbuf *p, struct netif *inp);
 156
 157 #define udp_init() /* Compatibility define, not init needed. */
 158
 159 #if UDP_DEBUG
 160 void udp_debug_print(struct udp_hdr *udphdr);
 161 #else
 162 #define udp_debug_print(udphdr)
 163 #endif
 164
 165 #ifdef __cplusplus
 166 }
 167 #endif
 168
 169 #endif /* LWIP_UDP */
 170
 171 #endif /* __LWIP_UDP_H__ */