xref: /third_party/lwip/src/apps/snmp/snmp_raw.c (revision 195972f6) 
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 */
46static void
47snmp_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
56err_t
57snmp_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
62u8_t
63snmp_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 */
86void
87snmp_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