1 /**
2 * @file
3 * SNMP RAW API 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 #include "lwip/ip_addr.h"
37
38 #if LWIP_SNMP && SNMP_USE_RAW
39
40 #include "lwip/udp.h"
41 #include "lwip/ip.h"
42 #include "lwip/prot/iana.h"
43 #include "snmp_msg.h"
44
45 /* lwIP UDP receive callback function */
46 static void
snmp_recv(void * arg,struct udp_pcb * pcb,struct pbuf * p,const ip_addr_t * addr,u16_t port)47 snmp_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port)
48 {
49 LWIP_UNUSED_ARG(arg);
50
51 snmp_receive(pcb, p, addr, port);
52
53 pbuf_free(p);
54 }
55
56 err_t
snmp_sendto(void * handle,struct pbuf * p,const ip_addr_t * dst,u16_t port)57 snmp_sendto(void *handle, struct pbuf *p, const ip_addr_t *dst, u16_t port)
58 {
59 return udp_sendto((struct udp_pcb *)handle, p, dst, port);
60 }
61
62 u8_t
snmp_get_local_ip_for_dst(void * handle,const ip_addr_t * dst,ip_addr_t * result)63 snmp_get_local_ip_for_dst(void *handle, const ip_addr_t *dst, ip_addr_t *result)
64 {
65 struct udp_pcb *udp_pcb = (struct udp_pcb *)handle;
66 struct netif *dst_if;
67 const ip_addr_t *dst_ip;
68
69 LWIP_UNUSED_ARG(udp_pcb); /* unused in case of IPV4 only configuration */
70
71 ip_route_get_local_ip(&udp_pcb->local_ip, dst, dst_if, dst_ip);
72
73 if ((dst_if != NULL) && (dst_ip != NULL)) {
74 ip_addr_copy(*result, *dst_ip);
75 return 1;
76 } else {
77 return 0;
78 }
79 }
80
81 /**
82 * @ingroup snmp_core
83 * Starts SNMP Agent.
84 * Allocates UDP pcb and binds it to IP_ANY_TYPE port 161.
85 */
86 void
snmp_init(void)87 snmp_init(void)
88 {
89 err_t err;
90
91 struct udp_pcb *snmp_pcb = udp_new_ip_type(IPADDR_TYPE_ANY);
92 LWIP_ERROR("snmp_raw: no PCB", (snmp_pcb != NULL), return;);
93
94 LWIP_ASSERT_CORE_LOCKED();
95
96 snmp_traps_handle = snmp_pcb;
97
98 udp_recv(snmp_pcb, snmp_recv, NULL);
99 err = udp_bind(snmp_pcb, IP_ANY_TYPE, LWIP_IANA_PORT_SNMP);
100 LWIP_ERROR("snmp_raw: Unable to bind PCB", (err == ERR_OK), return;);
101 }
102
103 #endif /* LWIP_SNMP && SNMP_USE_RAW */
104