1 /**
2  * @file
3  * UDP API (to be used from TCPIP thread)\n
4  * See also @ref udp_raw
5  */
6 
7 /*
8  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without modification,
12  * are permitted provided that the following conditions are met:
13  *
14  * 1. Redistributions of source code must retain the above copyright notice,
15  *    this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright notice,
17  *    this list of conditions and the following disclaimer in the documentation
18  *    and/or other materials provided with the distribution.
19  * 3. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
23  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
25  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
26  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
27  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
30  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
31  * OF SUCH DAMAGE.
32  *
33  * This file is part of the lwIP TCP/IP stack.
34  *
35  * Author: Adam Dunkels <adam@sics.se>
36  *
37  */
38 #ifndef LWIP_HDR_UDP_H
39 #define LWIP_HDR_UDP_H
40 
41 #include "lwip/opt.h"
42 
43 #if LWIP_UDP /* don't build if not configured for use in lwipopts.h */
44 
45 #include "lwip/pbuf.h"
46 #include "lwip/netif.h"
47 #include "lwip/ip_addr.h"
48 #include "lwip/ip.h"
49 #include "lwip/ip6_addr.h"
50 #include "lwip/prot/udp.h"
51 
52 #ifdef __cplusplus
53 extern "C" {
54 #endif
55 
56 #define UDP_FLAGS_NOCHKSUM       0x01U
57 #define UDP_FLAGS_UDPLITE        0x02U
58 #define UDP_FLAGS_CONNECTED      0x04U
59 #define UDP_FLAGS_MULTICAST_LOOP 0x08U
60 
61 struct udp_pcb;
62 
63 /** Function prototype for udp pcb receive callback functions
64  * addr and port are in same byte order as in the pcb
65  * The callback is responsible for freeing the pbuf
66  * if it's not used any more.
67  *
68  * ATTENTION: Be aware that 'addr' might point into the pbuf 'p' so freeing this pbuf
69  *            can make 'addr' invalid, too.
70  *
71  * @param arg user supplied argument (udp_pcb.recv_arg)
72  * @param pcb the udp_pcb which received data
73  * @param p the packet buffer that was received
74  * @param addr the remote IP address from which the packet was received
75  * @param port the remote port from which the packet was received
76  */
77 typedef void (*udp_recv_fn)(void *arg, struct udp_pcb *pcb, struct pbuf *p,
78     const ip_addr_t *addr, u16_t port);
79 
80 /** the UDP protocol control block */
81 struct udp_pcb {
82 /** Common members of all PCB types */
83   IP_PCB;
84 
85 /* Protocol specific PCB members */
86 
87   struct udp_pcb *next;
88 
89   u8_t flags;
90   /** ports are in host byte order */
91   u16_t local_port, remote_port;
92 
93 #if LWIP_MULTICAST_TX_OPTIONS
94   /** outgoing network interface for multicast packets */
95   ip_addr_t multicast_ip;
96   /** TTL for outgoing multicast packets */
97   u8_t mcast_ttl;
98 #endif /* LWIP_MULTICAST_TX_OPTIONS */
99 
100 #if LWIP_UDPLITE
101   /** used for UDP_LITE only */
102   u16_t chksum_len_rx, chksum_len_tx;
103 #endif /* LWIP_UDPLITE */
104 
105   /** receive callback function */
106   udp_recv_fn recv;
107   /** user-supplied argument for the recv callback */
108   void *recv_arg;
109 };
110 /* udp_pcbs export for external reference (e.g. SNMP agent) */
111 extern struct udp_pcb *udp_pcbs;
112 
113 /* The following functions is the application layer interface to the
114    UDP code. */
115 struct udp_pcb * udp_new        (void);
116 struct udp_pcb * udp_new_ip_type(u8_t type);
117 void             udp_remove     (struct udp_pcb *pcb);
118 err_t            udp_bind       (struct udp_pcb *pcb, const ip_addr_t *ipaddr,
119                                  u16_t port);
120 err_t            udp_connect    (struct udp_pcb *pcb, const ip_addr_t *ipaddr,
121                                  u16_t port);
122 void             udp_disconnect (struct udp_pcb *pcb);
123 void             udp_recv       (struct udp_pcb *pcb, udp_recv_fn recv,
124                                  void *recv_arg);
125 err_t            udp_sendto_if  (struct udp_pcb *pcb, struct pbuf *p,
126                                  const ip_addr_t *dst_ip, u16_t dst_port,
127                                  struct netif *netif);
128 err_t            udp_sendto_if_src(struct udp_pcb *pcb, struct pbuf *p,
129                                  const ip_addr_t *dst_ip, u16_t dst_port,
130                                  struct netif *netif, const ip_addr_t *src_ip);
131 err_t            udp_sendto     (struct udp_pcb *pcb, struct pbuf *p,
132                                  const ip_addr_t *dst_ip, u16_t dst_port);
133 err_t            udp_send       (struct udp_pcb *pcb, struct pbuf *p);
134 
135 #if LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP
136 err_t            udp_sendto_if_chksum(struct udp_pcb *pcb, struct pbuf *p,
137                                  const ip_addr_t *dst_ip, u16_t dst_port,
138                                  struct netif *netif, u8_t have_chksum,
139                                  u16_t chksum);
140 err_t            udp_sendto_chksum(struct udp_pcb *pcb, struct pbuf *p,
141                                  const ip_addr_t *dst_ip, u16_t dst_port,
142                                  u8_t have_chksum, u16_t chksum);
143 err_t            udp_send_chksum(struct udp_pcb *pcb, struct pbuf *p,
144                                  u8_t have_chksum, u16_t chksum);
145 err_t            udp_sendto_if_src_chksum(struct udp_pcb *pcb, struct pbuf *p,
146                                  const ip_addr_t *dst_ip, u16_t dst_port, struct netif *netif,
147                                  u8_t have_chksum, u16_t chksum, const ip_addr_t *src_ip);
148 #endif /* LWIP_CHECKSUM_ON_COPY && CHECKSUM_GEN_UDP */
149 
150 #define          udp_flags(pcb) ((pcb)->flags)
151 #define          udp_setflags(pcb, f)  ((pcb)->flags = (f))
152 
153 /* The following functions are the lower layer interface to UDP. */
154 void             udp_input      (struct pbuf *p, struct netif *inp);
155 
156 void             udp_init       (void);
157 
158 /* for compatibility with older implementation */
159 #define udp_new_ip6() udp_new_ip_type(IPADDR_TYPE_V6)
160 
161 #if LWIP_MULTICAST_TX_OPTIONS
162 #define udp_set_multicast_netif_addr(pcb, ip4addr) ip_addr_copy_from_ip4((pcb)->multicast_ip, *(ip4addr))
163 #define udp_get_multicast_netif_addr(pcb)          ip_2_ip4(&(pcb)->multicast_ip)
164 #define udp_set_multicast_ttl(pcb, value)      do { (pcb)->mcast_ttl = value; } while(0)
165 #define udp_get_multicast_ttl(pcb)                 ((pcb)->mcast_ttl)
166 #endif /* LWIP_MULTICAST_TX_OPTIONS */
167 
168 #if UDP_DEBUG
169 void udp_debug_print(struct udp_hdr *udphdr);
170 #else
171 #define udp_debug_print(udphdr)
172 #endif
173 
174 void udp_netif_ip_addr_changed(const ip_addr_t* old_addr, const ip_addr_t* new_addr);
175 
176 #ifdef __cplusplus
177 }
178 #endif
179 
180 #endif /* LWIP_UDP */
181 
182 #endif /* LWIP_HDR_UDP_H */
183