1 /*
2 * Copyright (c) 2008, XenSource Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 * * Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * * 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 * * Neither the name of XenSource Inc. nor the names of its contributors
13 * may be used to endorse or promote products derived from this software
14 * without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
20 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
23 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
24 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
25 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
26 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28 #include <stdio.h>
29 #include <errno.h>
30 #include <unistd.h>
31 #include <string.h>
32
33 #include "tap-ctl.h"
34 #include "blktap2.h"
35
36 int
tap_ctl_check_blktap(const char ** msg)37 tap_ctl_check_blktap(const char **msg)
38 {
39 FILE *f;
40 int err = 0, minor;
41 char name[32];
42
43 memset(name, 0, sizeof(name));
44
45 f = fopen("/proc/misc", "r");
46 if (!f) {
47 *msg = "failed to open /proc/misc";
48 return -errno;
49 }
50
51 while (fscanf(f, "%d %32s", &minor, name) == 2) {
52 if (!strcmp(name, BLKTAP2_CONTROL_NAME))
53 goto out;
54 }
55
56 err = -ENOSYS;
57 *msg = "blktap kernel module not installed";
58
59 out:
60 fclose(f);
61 return err;
62 }
63
64 int
tap_ctl_check(const char ** msg)65 tap_ctl_check(const char **msg)
66 {
67 int err;
68 uid_t uid;
69
70 err = tap_ctl_check_blktap(msg);
71 if (err)
72 goto out;
73
74 err = 0;
75 *msg = "ok";
76
77 out:
78 return err;
79 }
80