1/*
2 * Copyright (C) 2011, 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <stdlib.h>
18#include <stdio.h>
19#include <sys/types.h>
20#include <sys/stat.h>
21#include <fcntl.h>
22#include <unistd.h>
23#include <sys/ioctl.h>
24#include <linux/fs.h>
25#include <errno.h>
26
27typedef unsigned long long u64;
28
29#ifndef BLKDISCARD
30#define BLKDISCARD _IO(0x12,119)
31#endif
32
33#ifndef BLKSECDISCARD
34#define BLKSECDISCARD _IO(0x12,125)
35#endif
36
37static u64 get_block_device_size(int fd)
38{
39        u64 size = 0;
40        int ret;
41
42        ret = ioctl(fd, BLKGETSIZE64, &size);
43
44        if (ret)
45                return 0;
46
47        return size;
48}
49
50static int wipe_block_device(int fd, u64 len, int secure)
51{
52    u64 range[2];
53    int ret;
54    int req;
55
56    range[0] = 0;
57    range[1] = len;
58    if (secure) {
59       req = BLKSECDISCARD;
60    } else {
61       req = BLKDISCARD;
62    }
63
64    ret = ioctl(fd, req, &range);
65    if (ret < 0) {
66        fprintf(stderr, "%s discard failed, errno = %d\n",
67                secure ? "Secure" : "Nonsecure", errno);
68    }
69
70    return ret;
71}
72
73static void usage(void)
74{
75    fprintf(stderr, "Usage: wipe_blkdev [-s] <partition>\n");
76    exit(1);
77}
78
79int main(int argc, char *argv[])
80{
81    int secure = 0;
82    char *devname;
83    int fd;
84    u64 len;
85    struct stat statbuf;
86    int ret;
87
88    if ((argc != 2) && (argc != 3)) {
89        usage();
90    }
91
92    if (argc == 3) {
93        if (!strcmp(argv[1], "-s")) {
94            secure = 1;
95            devname = argv[2];
96        } else {
97            usage();
98        }
99    } else {
100        devname = argv[1];
101    }
102
103    fd = open(devname, O_RDWR);
104    if (fd < 0) {
105        fprintf(stderr, "Cannot open device %s\n", devname);
106        exit(1);
107    }
108
109    if (fstat(fd, &statbuf) < 0) {
110        fprintf(stderr, "Cannot stat %s\n", devname);
111        exit(1);
112    }
113
114    if (!S_ISBLK(statbuf.st_mode)) {
115        fprintf(stderr, "%s is not a block device\n", devname);
116        exit(1);
117    }
118
119    len = get_block_device_size(fd);
120
121    if (! len) {
122        fprintf(stderr, "Cannot get size of block device %s\n", devname);
123        exit(1);
124    }
125
126    ret = wipe_block_device(fd, len, secure);
127
128    close(fd);
129
130    return ret;
131}
132