xref: /freebsd/lib/libifconfig/libifconfig_bridge.c (revision 0a36787e4c1fa0cf77dcf83be0867178476e372b)
1 /*
2  * Copyright (c) 2020, Ryan Moeller <freqlabs@FreeBSD.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  *
25  * $FreeBSD$
26  */
27 #include <sys/param.h>
28 #include <sys/ioctl.h>
29 
30 #include <net/ethernet.h>
31 #include <net/if.h>
32 #include <net/if_bridgevar.h>
33 #include <net/route.h>
34 
35 #include <assert.h>
36 #include <errno.h>
37 #include <stdbool.h>
38 #include <stdlib.h>
39 #include <string.h>
40 
41 #include "libifconfig.h"
42 #include "libifconfig_internal.h"
43 
44 /* Internal structure used for allocations and frees */
45 struct _ifconfig_bridge_status {
46 	struct ifconfig_bridge_status inner;	/* wrapped bridge status */
47 	struct ifbropreq params;		/* operational parameters */
48 };
49 
50 static int
51 ifconfig_bridge_ioctlwrap(ifconfig_handle_t *h, const char *name,
52     unsigned long cmd, void *arg, size_t arglen, bool set)
53 {
54 	struct ifdrv ifd = { 0 };
55 	unsigned long req = set ? SIOCSDRVSPEC : SIOCGDRVSPEC;
56 
57 	strlcpy(ifd.ifd_name, name, sizeof(ifd.ifd_name));
58 	ifd.ifd_cmd = cmd;
59 	ifd.ifd_data = arg;
60 	ifd.ifd_len = arglen;
61 
62 	return (ifconfig_ioctlwrap(h, AF_LOCAL, req, &ifd));
63 }
64 
65 int
66 ifconfig_bridge_get_bridge_status(ifconfig_handle_t *h,
67     const char *name, struct ifconfig_bridge_status **bridgep)
68 {
69 	struct ifbifconf members;
70 	struct ifbrparam cache_param;
71 	struct _ifconfig_bridge_status *bridge;
72 	char *buf;
73 
74 	*bridgep = NULL;
75 
76 	bridge = calloc(1, sizeof(struct _ifconfig_bridge_status));
77 	if (bridge == NULL) {
78 		h->error.errtype = OTHER;
79 		h->error.errcode = ENOMEM;
80 		return (-1);
81 	}
82 	bridge->inner.params = &bridge->params;
83 
84 	if (ifconfig_bridge_ioctlwrap(h, name, BRDGGCACHE,
85 	    &cache_param, sizeof(cache_param), false) != 0) {
86 		free(bridge);
87 		return (-1);
88 	}
89 	bridge->inner.cache_size = cache_param.ifbrp_csize;
90 
91 	if (ifconfig_bridge_ioctlwrap(h, name, BRDGGTO,
92 	    &cache_param, sizeof(cache_param), false) != 0) {
93 		free(bridge);
94 		return (-1);
95 	}
96 	bridge->inner.cache_lifetime = cache_param.ifbrp_ctime;
97 
98 	if (ifconfig_bridge_ioctlwrap(h, name, BRDGPARAM,
99 	    &bridge->params, sizeof(bridge->params), false) != 0) {
100 		free(bridge);
101 		return (-1);
102 	}
103 
104 	members.ifbic_buf = NULL;
105 	for (size_t len = 8192;
106 	    (buf = realloc(members.ifbic_buf, len)) != NULL;
107 	    len *= 2) {
108 		members.ifbic_buf = buf;
109 		members.ifbic_len = len;
110 		if (ifconfig_bridge_ioctlwrap(h, name, BRDGGIFS,
111 		    &members, sizeof(members), false) != 0) {
112 			free(buf);
113 			free(bridge);
114 			return (-1);
115 		}
116 		if (members.ifbic_len <= len)
117 			break;
118 	}
119 	if (buf == NULL) {
120 		free(members.ifbic_buf);
121 		free(bridge);
122 		h->error.errtype = OTHER;
123 		h->error.errcode = ENOMEM;
124 		return (-1);
125 	}
126 	bridge->inner.members = members.ifbic_req;
127 	bridge->inner.members_count =
128 	    members.ifbic_len / sizeof(*members.ifbic_req);
129 
130 	*bridgep = &bridge->inner;
131 
132 	return (0);
133 }
134 
135 void
136 ifconfig_bridge_free_bridge_status(struct ifconfig_bridge_status *bridge)
137 {
138 	if (bridge != NULL) {
139 		free(bridge->members);
140 		free(bridge);
141 	}
142 }
143