1 /**
2  * @file
3  * SNMP netconn frontend.
4  */
5 
6 /*
7  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without modification,
11  * are permitted provided that the following conditions are met:
12  *
13  * 1. Redistributions of source code must retain the above copyright notice,
14  *    this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright notice,
16  *    this list of conditions and the following disclaimer in the documentation
17  *    and/or other materials provided with the distribution.
18  * 3. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
22  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
24  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
26  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
29  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
30  * OF SUCH DAMAGE.
31  *
32  * Author: Dirk Ziegelmeier <dziegel@gmx.de>
33  */
34 
35 #include "lwip/apps/snmp_opts.h"
36 
37 #if LWIP_SNMP && SNMP_USE_NETCONN
38 
39 #include <string.h>
40 #include "lwip/api.h"
41 #include "lwip/ip.h"
42 #include "lwip/udp.h"
43 #include "snmp_msg.h"
44 #include "lwip/sys.h"
45 
46 /** SNMP netconn API worker thread */
47 static void
48 snmp_netconn_thread(void *arg)
49 {
50   struct netconn *conn;
51   struct netbuf *buf;
52   err_t err;
53   LWIP_UNUSED_ARG(arg);
54 
55   /* Bind to SNMP port with default IP address */
56 #if LWIP_IPV6
57   conn = netconn_new(NETCONN_UDP_IPV6);
58   netconn_bind(conn, IP6_ADDR_ANY, SNMP_IN_PORT);
59 #else /* LWIP_IPV6 */
60   conn = netconn_new(NETCONN_UDP);
61   netconn_bind(conn, IP4_ADDR_ANY, SNMP_IN_PORT);
62 #endif /* LWIP_IPV6 */
63   LWIP_ERROR("snmp_netconn: invalid conn", (conn != NULL), return;);
64 
65   snmp_traps_handle = conn;
66 
67   do {
68     err = netconn_recv(conn, &buf);
69 
70     if (err == ERR_OK) {
71       snmp_receive(conn, buf->p, &buf->addr, buf->port);
72     }
73 
74     if (buf != NULL) {
75       netbuf_delete(buf);
76     }
77   } while(1);
78 }
79 
80 err_t
81 snmp_sendto(void *handle, struct pbuf *p, const ip_addr_t *dst, u16_t port)
82 {
83   err_t result;
84   struct netbuf buf;
85 
86   memset(&buf, 0, sizeof(buf));
87   buf.p = p;
88   result = netconn_sendto((struct netconn*)handle, &buf, dst, port);
89 
90   return result;
91 }
92 
93 u8_t
94 snmp_get_local_ip_for_dst(void* handle, const ip_addr_t *dst, ip_addr_t *result)
95 {
96   struct netconn* conn = (struct netconn*)handle;
97   struct netif *dst_if;
98   const ip_addr_t* dst_ip;
99 
100   LWIP_UNUSED_ARG(conn); /* unused in case of IPV4 only configuration */
101 
102   ip_route_get_local_ip(&conn->pcb.udp->local_ip, dst, dst_if, dst_ip);
103 
104   if ((dst_if != NULL) && (dst_ip != NULL)) {
105     ip_addr_copy(*result, *dst_ip);
106     return 1;
107   } else {
108     return 0;
109   }
110 }
111 
112 /**
113  * Starts SNMP Agent.
114  */
115 void
116 snmp_init(void)
117 {
118   sys_thread_new("snmp_netconn", snmp_netconn_thread, NULL, SNMP_STACK_SIZE, SNMP_THREAD_PRIO);
119 }
120 
121 #endif /* LWIP_SNMP && SNMP_USE_NETCONN */
122