include/lwip/udp.h

0001 /*
0002  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
0003  * All rights reserved.
0004  *
0005  * Redistribution and use in source and binary forms, with or without modification,
0006  * are permitted provided that the following conditions are met:
0007  *
0008  * 1. Redistributions of source code must retain the above copyright notice,
0009  *    this list of conditions and the following disclaimer.
0010  * 2. Redistributions in binary form must reproduce the above copyright notice,
0011  *    this list of conditions and the following disclaimer in the documentation
0012  *    and/or other materials provided with the distribution.
0013  * 3. The name of the author may not be used to endorse or promote products
0014  *    derived from this software without specific prior written permission.
0015  *
0016  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
0017  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
0018  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
0019  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
0020  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
0021  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0022  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0023  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
0024  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
0025  * OF SUCH DAMAGE.
0026  *
0027  * This file is part of the lwIP TCP/IP stack.
0028  *
0029  * Author: Adam Dunkels <adam@sics.se>
0030  *
0031  */
0032 #ifndef __LWIP_UDP_H__
0033 #define __LWIP_UDP_H__
0034
0035 #include "lwip/opt.h"
0036
0037 #if LWIP_UDP /* don't build if not configured for use in lwipopts.h */
0038
0039 #include "lwip/pbuf.h"
0040 #include "lwip/netif.h"
0041 #include "lwip/ip_addr.h"
0042 #include "lwip/ip.h"
0043
0044 #ifdef __cplusplus
0045 extern "C" {
0046 #endif
0047
0048 #define UDP_HLEN 8
0049
0050 /* Fields are (of course) in network byte order. */
0051 #ifdef PACK_STRUCT_USE_INCLUDES
0052 #  include "arch/bpstruct.h"
0053 #endif
0054 PACK_STRUCT_BEGIN
0055 struct udp_hdr {
0056   PACK_STRUCT_FIELD(u16_t src);
0057   PACK_STRUCT_FIELD(u16_t dest);  /* src/dest UDP ports */
0058   PACK_STRUCT_FIELD(u16_t len);
0059   PACK_STRUCT_FIELD(u16_t chksum);
0060 } PACK_STRUCT_STRUCT;
0061 PACK_STRUCT_END
0062 #ifdef PACK_STRUCT_USE_INCLUDES
0063 #  include "arch/epstruct.h"
0064 #endif
0065
0066 #define UDP_FLAGS_NOCHKSUM 0x01U
0067 #define UDP_FLAGS_UDPLITE  0x02U
0068 #define UDP_FLAGS_CONNECTED  0x04U
0069
0070 struct udp_pcb {
0071 /* Common members of all PCB types */
0072   IP_PCB;
0073
0074 /* Protocol specific PCB members */
0075
0076   struct udp_pcb *next;
0077
0078   u8_t flags;
0079   /* ports are in host byte order */
0080   u16_t local_port, remote_port;
0081
0082 #if LWIP_IGMP
0083   /* outgoing network interface for multicast packets */
0084   struct ip_addr multicast_ip;
0085 #endif /* LWIP_IGMP */
0086
0087 #if LWIP_UDPLITE
0088   /* used for UDP_LITE only */
0089   u16_t chksum_len_rx, chksum_len_tx;
0090 #endif /* LWIP_UDPLITE */
0091
0092   /* receive callback function
0093    * addr and port are in same byte order as in the pcb
0094    * The callback is responsible for freeing the pbuf
0095    * if it's not used any more.
0096    *
0097    * ATTENTION: Be aware that 'addr' points into the pbuf 'p' so freeing this pbuf
0098    *            makes 'addr' invalid, too.
0099    *
0100    * @param arg user supplied argument (udp_pcb.recv_arg)
0101    * @param pcb the udp_pcb which received data
0102    * @param p the packet buffer that was received
0103    * @param addr the remote IP address from which the packet was received
0104    * @param port the remote port from which the packet was received
0105    */
0106   void (* recv)(void *arg, struct udp_pcb *pcb, struct pbuf *p,
0107     struct ip_addr *addr, u16_t port);
0108   /* user-supplied argument for the recv callback */
0109   void *recv_arg;
0110 };
0111 /* udp_pcbs export for exernal reference (e.g. SNMP agent) */
0112 extern struct udp_pcb *udp_pcbs;
0113
0114 /* The following functions is the application layer interface to the
0115    UDP code. */
0116 struct udp_pcb * udp_new        (void);
0117 void             udp_remove     (struct udp_pcb *pcb);
0118 err_t            udp_bind       (struct udp_pcb *pcb, struct ip_addr *ipaddr,
0119                  u16_t port);
0120 err_t            udp_connect    (struct udp_pcb *pcb, struct ip_addr *ipaddr,
0121                  u16_t port);
0122 void             udp_disconnect    (struct udp_pcb *pcb);
0123 void             udp_recv       (struct udp_pcb *pcb,
0124          void (* recv)(void *arg, struct udp_pcb *upcb,
0125                  struct pbuf *p,
0126                  struct ip_addr *addr,
0127                  u16_t port),
0128          void *recv_arg);
0129 err_t            udp_sendto_if  (struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *dst_ip, u16_t dst_port, struct netif *netif);
0130 err_t            udp_sendto     (struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *dst_ip, u16_t dst_port);
0131 err_t            udp_send       (struct udp_pcb *pcb, struct pbuf *p);
0132
0133 #define          udp_flags(pcb)  ((pcb)->flags)
0134 #define          udp_setflags(pcb, f)  ((pcb)->flags = (f))
0135
0136 /* The following functions are the lower layer interface to UDP. */
0137 void             udp_input      (struct pbuf *p, struct netif *inp);
0138
0139 #define udp_init() /* Compatibility define, not init needed. */
0140
0141 #if UDP_DEBUG
0142 void udp_debug_print(struct udp_hdr *udphdr);
0143 #else
0144 #define udp_debug_print(udphdr)
0145 #endif
0146
0147 #ifdef __cplusplus
0148 }
0149 #endif
0150
0151 #endif /* LWIP_UDP */
0152
0153 #endif /* __LWIP_UDP_H__ */