udp.h

00001 /*
00002  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
00003  * All rights reserved. 
00004  * 
00005  * Redistribution and use in source and binary forms, with or without modification, 
00006  * are permitted provided that the following conditions are met:
00007  *
00008  * 1. Redistributions of source code must retain the above copyright notice,
00009  *    this list of conditions and the following disclaimer.
00010  * 2. Redistributions in binary form must reproduce the above copyright notice,
00011  *    this list of conditions and the following disclaimer in the documentation
00012  *    and/or other materials provided with the distribution.
00013  * 3. The name of the author may not be used to endorse or promote products
00014  *    derived from this software without specific prior written permission. 
00015  *
00016  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
00017  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
00018  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
00019  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
00020  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
00021  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
00022  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
00023  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
00024  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
00025  * OF SUCH DAMAGE.
00026  *
00027  * This file is part of the lwIP TCP/IP stack.
00028  * 
00029  * Author: Adam Dunkels <adam@sics.se>
00030  *
00031  */
00032 #ifndef __LWIP_UDP_H__
00033 #define __LWIP_UDP_H__
00034 
00035 #include "lwip/opt.h"
00036 
00037 #if LWIP_UDP /* don't build if not configured for use in lwipopts.h */
00038 
00039 #include "lwip/pbuf.h"
00040 #include "lwip/netif.h"
00041 #include "lwip/ip_addr.h"
00042 #include "lwip/ip.h"
00043 
00044 #ifdef __cplusplus
00045 extern "C" {
00046 #endif
00047 
00048 #define UDP_HLEN 8
00049 
00050 /* Fields are (of course) in network byte order. */
00051 #ifdef PACK_STRUCT_USE_INCLUDES
00052 #  include "arch/bpstruct.h"
00053 #endif
00054 PACK_STRUCT_BEGIN
00055 struct udp_hdr {
00056   PACK_STRUCT_FIELD(u16_t src);
00057   PACK_STRUCT_FIELD(u16_t dest);  /* src/dest UDP ports */
00058   PACK_STRUCT_FIELD(u16_t len);
00059   PACK_STRUCT_FIELD(u16_t chksum);
00060 } PACK_STRUCT_STRUCT;
00061 PACK_STRUCT_END
00062 #ifdef PACK_STRUCT_USE_INCLUDES
00063 #  include "arch/epstruct.h"
00064 #endif
00065 
00066 #define UDP_FLAGS_NOCHKSUM 0x01U
00067 #define UDP_FLAGS_UDPLITE  0x02U
00068 #define UDP_FLAGS_CONNECTED  0x04U
00069 
00070 struct udp_pcb {
00071 /* Common members of all PCB types */
00072   IP_PCB;
00073 
00074 /* Protocol specific PCB members */
00075 
00076   struct udp_pcb *next;
00077 
00078   u8_t flags;
00079   /* ports are in host byte order */
00080   u16_t local_port, remote_port;
00081 
00082 #if LWIP_IGMP
00083   /* outgoing network interface for multicast packets */
00084   struct ip_addr multicast_ip;
00085 #endif /* LWIP_IGMP */
00086 
00087 #if LWIP_UDPLITE
00088   /* used for UDP_LITE only */
00089   u16_t chksum_len_rx, chksum_len_tx;
00090 #endif /* LWIP_UDPLITE */
00091 
00092   /* receive callback function
00093    * addr and port are in same byte order as in the pcb
00094    * The callback is responsible for freeing the pbuf
00095    * if it's not used any more.
00096    *
00097    * ATTENTION: Be aware that 'addr' points into the pbuf 'p' so freeing this pbuf
00098    *            makes 'addr' invalid, too.
00099    *
00100    * @param arg user supplied argument (udp_pcb.recv_arg)
00101    * @param pcb the udp_pcb which received data
00102    * @param p the packet buffer that was received
00103    * @param addr the remote IP address from which the packet was received
00104    * @param port the remote port from which the packet was received
00105    */
00106   void (* recv)(void *arg, struct udp_pcb *pcb, struct pbuf *p,
00107     struct ip_addr *addr, u16_t port);
00108   /* user-supplied argument for the recv callback */
00109   void *recv_arg;  
00110 };
00111 /* udp_pcbs export for exernal reference (e.g. SNMP agent) */
00112 extern struct udp_pcb *udp_pcbs;
00113 
00114 /* The following functions is the application layer interface to the
00115    UDP code. */
00116 struct udp_pcb * udp_new        (void);
00117 void             udp_remove     (struct udp_pcb *pcb);
00118 err_t            udp_bind       (struct udp_pcb *pcb, struct ip_addr *ipaddr,
00119                  u16_t port);
00120 err_t            udp_connect    (struct udp_pcb *pcb, struct ip_addr *ipaddr,
00121                  u16_t port);
00122 void             udp_disconnect    (struct udp_pcb *pcb);
00123 void             udp_recv       (struct udp_pcb *pcb,
00124          void (* recv)(void *arg, struct udp_pcb *upcb,
00125                  struct pbuf *p,
00126                  struct ip_addr *addr,
00127                  u16_t port),
00128          void *recv_arg);
00129 err_t            udp_sendto_if  (struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *dst_ip, u16_t dst_port, struct netif *netif);
00130 err_t            udp_sendto     (struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *dst_ip, u16_t dst_port);
00131 err_t            udp_send       (struct udp_pcb *pcb, struct pbuf *p);
00132 
00133 #define          udp_flags(pcb)  ((pcb)->flags)
00134 #define          udp_setflags(pcb, f)  ((pcb)->flags = (f))
00135 
00136 /* The following functions are the lower layer interface to UDP. */
00137 void             udp_input      (struct pbuf *p, struct netif *inp);
00138 
00139 #define udp_init() /* Compatibility define, not init needed. */
00140 
00141 #if UDP_DEBUG
00142 void udp_debug_print(struct udp_hdr *udphdr);
00143 #else
00144 #define udp_debug_print(udphdr)
00145 #endif
00146 
00147 #ifdef __cplusplus
00148 }
00149 #endif
00150 
00151 #endif /* LWIP_UDP */
00152 
00153 #endif /* __LWIP_UDP_H__ */