1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2010-2011 Monthadar Al Jaberi, TerraNet AB
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer,
12 * without modification.
13 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
14 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
15 * redistribution must be conditioned upon including a substantially
16 * similar Disclaimer requirement for further binary redistribution.
17 *
18 * NO WARRANTY
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
22 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
23 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
24 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
27 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
29 * THE POSSIBILITY OF SUCH DAMAGES.
30 */
31 #include "if_wtapvar.h"
32 #include "if_medium.h"
33
34 void
init_medium(struct wtap_medium * md)35 init_medium(struct wtap_medium *md)
36 {
37
38 DWTAP_PRINTF("%s\n", __func__);
39 STAILQ_INIT(&md->md_pktbuf);
40 mtx_init(&md->md_mtx, "wtap_medium mtx", NULL, MTX_DEF | MTX_RECURSE);
41
42 /* Event handler for sending packets between wtaps */
43 struct eventhandler *eh = (struct eventhandler *)
44 malloc(sizeof(struct eventhandler), M_WTAP, M_NOWAIT | M_ZERO);
45 eh->tq = taskqueue_create("wtap_tx_taskq", M_NOWAIT | M_ZERO,
46 taskqueue_thread_enqueue, &eh->tq);
47 taskqueue_start_threads(&eh->tq, 1, PI_NET, "%s taskq", "wtap_medium");
48 md->tx_handler = eh;
49 /* Mark medium closed by default */
50 md->open = 0;
51 }
52
53 void
deinit_medium(struct wtap_medium * md)54 deinit_medium(struct wtap_medium *md)
55 {
56
57 DWTAP_PRINTF("%s\n", __func__);
58 taskqueue_free(md->tx_handler->tq);
59 free(md->tx_handler, M_WTAP);
60 }
61
62 int
medium_transmit(struct wtap_medium * md,int id,struct mbuf * m)63 medium_transmit(struct wtap_medium *md, int id, struct mbuf*m)
64 {
65
66 mtx_lock(&md->md_mtx);
67 if (md->open == 0){
68 DWTAP_PRINTF("[%d] dropping m=%p\n", id, m);
69 m_free(m);
70 mtx_unlock(&md->md_mtx);
71 return 0;
72 }
73
74 DWTAP_PRINTF("[%d] transmiting m=%p\n", id, m);
75 struct packet *p = (struct packet *)malloc(sizeof(struct packet),
76 M_WTAP_PACKET, M_ZERO | M_NOWAIT);
77 p->id = id;
78 p->m = m;
79
80 STAILQ_INSERT_TAIL(&md->md_pktbuf, p, pf_list);
81 taskqueue_enqueue(md->tx_handler->tq, &md->tx_handler->proc);
82 mtx_unlock(&md->md_mtx);
83
84 return 0;
85 }
86
87 struct packet *
medium_get_next_packet(struct wtap_medium * md)88 medium_get_next_packet(struct wtap_medium *md)
89 {
90 struct packet *p;
91
92 mtx_lock(&md->md_mtx);
93 p = STAILQ_FIRST(&md->md_pktbuf);
94 if (p == NULL){
95 mtx_unlock(&md->md_mtx);
96 return NULL;
97 }
98
99 STAILQ_REMOVE_HEAD(&md->md_pktbuf, pf_list);
100 mtx_unlock(&md->md_mtx);
101 return p;
102 }
103
104 void
medium_open(struct wtap_medium * md)105 medium_open(struct wtap_medium *md)
106 {
107
108 mtx_lock(&md->md_mtx);
109 md->open = 1;
110 mtx_unlock(&md->md_mtx);
111 }
112
113 void
medium_close(struct wtap_medium * md)114 medium_close(struct wtap_medium *md)
115 {
116
117 mtx_lock(&md->md_mtx);
118 md->open = 0;
119 mtx_unlock(&md->md_mtx);
120 }
121