xref: /openbsd/sbin/vnconfig/vnconfig.c (revision 5a38ef86)
1 /*	$OpenBSD: vnconfig.c,v 1.7 2021/10/25 19:54:29 kn Exp $	*/
2 /*
3  * Copyright (c) 1993 University of Utah.
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * the Systems Programming Group of the University of Utah Computer
9  * Science Department.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34 e */
35 
36 #include <sys/param.h>	/* DEV_BSIZE */
37 #include <sys/ioctl.h>
38 #include <sys/stat.h>
39 #include <sys/disklabel.h>
40 
41 #include <dev/vndioctl.h>
42 
43 #include <blf.h>
44 #include <err.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <readpassphrase.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <limits.h>
53 #include <util.h>
54 
55 #define DEFAULT_VND	"vnd0"
56 
57 #define VND_CONFIG	1
58 #define VND_UNCONFIG	2
59 #define VND_GETINFO	3
60 
61 int verbose = 0;
62 
63 __dead void	 usage(void);
64 int		 config(char *, char *, struct disklabel *, char *, size_t);
65 int		 unconfig(char *);
66 int		 getinfo(const char *, int *availp);
67 char		*get_pkcs_key(char *, char *);
68 
69 int
70 main(int argc, char **argv)
71 {
72 	int	 ch, rv, action, opt_k = 0, opt_K = 0, opt_l = 0, opt_u = 0;
73 	char	*key = NULL, *rounds = NULL, *saltopt = NULL;
74 	char	*file, *vnd;
75 	size_t	 keylen = 0;
76 	extern char *__progname;
77 	struct disklabel *dp = NULL;
78 
79 	action = VND_CONFIG;
80 
81 	while ((ch = getopt(argc, argv, "ckK:lo:S:t:uv")) != -1) {
82 		switch (ch) {
83 		case 'c':
84 			/* backwards compat: delete in 2020 */
85 			break;
86 		case 'k':
87 			opt_k = 1;
88 			break;
89 		case 'K':
90 			opt_K = 1;
91 			rounds = optarg;
92 			break;
93 		case 'l':
94 			opt_l = 1;
95 			break;
96 		case 'S':
97 			saltopt = optarg;
98 			break;
99 		case 't':
100 			dp = getdiskbyname(optarg);
101 			if (dp == NULL)
102 				errx(1, "unknown disk type: %s", optarg);
103 			break;
104 		case 'u':
105 			opt_u = 1;
106 			break;
107 		case 'v':
108 			verbose = 1;
109 			break;
110 		default:
111 			usage();
112 			/* NOTREACHED */
113 		}
114 	}
115 	argc -= optind;
116 	argv += optind;
117 
118 	if (opt_l + opt_u > 1)
119 		errx(1, "-l and -u are mutually exclusive options");
120 
121 	if (opt_l)
122 		action = VND_GETINFO;
123 	else if (opt_u)
124 		action = VND_UNCONFIG;
125 
126 	if (saltopt && (!opt_K))
127 		errx(1, "-S only makes sense when used with -K");
128 
129 	if (action == VND_CONFIG) {
130 		if (argc == 1) {
131 			file = argv[0];
132 			vnd = NULL;
133 		} else if (argc == 2) {
134 			vnd = argv[0];
135 			file = argv[1];
136 		} else
137 			usage();
138 
139 		if (opt_k || opt_K)
140 			fprintf(stderr, "WARNING: Consider using softraid crypto.\n");
141 		if (opt_k) {
142 			if (opt_K)
143 				errx(1, "-k and -K are mutually exclusive");
144 			key = getpass("Encryption key: ");
145 			if (key == NULL || (keylen = strlen(key)) == 0)
146 				errx(1, "Need an encryption key");
147 		} else if (opt_K) {
148 			key = get_pkcs_key(rounds, saltopt);
149 			keylen = BLF_MAXUTILIZED;
150 		}
151 		rv = config(file, vnd, dp, key, keylen);
152 	} else if (action == VND_UNCONFIG && argc == 1)
153 		rv = unconfig(argv[0]);
154 	else if (action == VND_GETINFO)
155 		rv = getinfo(argc ? argv[0] : NULL, NULL);
156 	else
157 		usage();
158 
159 	exit(rv);
160 }
161 
162 char *
163 get_pkcs_key(char *arg, char *saltopt)
164 {
165 	char		 passphrase[128] = {'\0'};
166 	char		 saltbuf[128] = {'\0'}, saltfilebuf[PATH_MAX];
167 	char		*key = NULL;
168 	char		*saltfile;
169 	const char	*errstr;
170 	int		 rounds;
171 
172 	rounds = strtonum(arg, 1000, INT_MAX, &errstr);
173 	if (errstr)
174 		err(1, "rounds: %s", errstr);
175 	if (readpassphrase("Encryption key: ", passphrase, sizeof(passphrase),
176 	    RPP_REQUIRE_TTY) == NULL)
177 		errx(1, "Unable to read passphrase");
178 	if (saltopt)
179 		saltfile = saltopt;
180 	else {
181 		printf("Salt file: ");
182 		fflush(stdout);
183 		saltfile = fgets(saltfilebuf, sizeof(saltfilebuf), stdin);
184 		if (saltfile)
185 			saltfile[strcspn(saltfile, "\n")] = '\0';
186 	}
187 	if (!saltfile || saltfile[0] == '\0')
188 		warnx("Skipping salt file, insecure");
189 	else {
190 		int fd;
191 
192 		fd = open(saltfile, O_RDONLY);
193 		if (fd == -1) {
194 			int *s;
195 
196 			fprintf(stderr, "Salt file not found, attempting to "
197 			    "create one\n");
198 			fd = open(saltfile, O_RDWR|O_CREAT|O_EXCL, 0600);
199 			if (fd == -1)
200 				err(1, "Unable to create salt file: '%s'",
201 				    saltfile);
202 			for (s = (int *)saltbuf;
203 			    s < (int *)(saltbuf + sizeof(saltbuf)); s++)
204 				*s = arc4random();
205 			if (write(fd, saltbuf, sizeof(saltbuf))
206 			    != sizeof(saltbuf))
207 				err(1, "Unable to write salt file: '%s'",
208 				    saltfile);
209 			fprintf(stderr, "Salt file created as '%s'\n",
210 			    saltfile);
211 		} else {
212 			if (read(fd, saltbuf, sizeof(saltbuf))
213 			    != sizeof(saltbuf))
214 				err(1, "Unable to read salt file: '%s'",
215 				    saltfile);
216 		}
217 		close(fd);
218 	}
219 	if ((key = calloc(1, BLF_MAXUTILIZED)) == NULL)
220 		err(1, NULL);
221 	if (pkcs5_pbkdf2(passphrase, sizeof(passphrase), saltbuf,
222 	    sizeof (saltbuf), key, BLF_MAXUTILIZED, rounds))
223 		errx(1, "pkcs5_pbkdf2 failed");
224 	explicit_bzero(passphrase, sizeof(passphrase));
225 
226 	return (key);
227 }
228 
229 int
230 getinfo(const char *vname, int *availp)
231 {
232 	int vd, print_all = 0;
233 	struct vnd_user vnu;
234 
235 	if (vname == NULL) {
236 		vname = DEFAULT_VND;
237 		print_all = 1;
238 	}
239 
240 	vd = opendev((char *)vname, O_RDONLY, OPENDEV_PART, NULL);
241 	if (vd == -1)
242 		err(1, "open: %s", vname);
243 
244 	vnu.vnu_unit = -1;
245 
246 query:
247 	if (ioctl(vd, VNDIOCGET, &vnu) == -1) {
248 		if (print_all && errno == ENXIO && vnu.vnu_unit > 0)
249 			goto end;
250 		err(1, "ioctl: %s", vname);
251 	}
252 
253 	if (availp) {
254 		if (!vnu.vnu_ino) {
255 			*availp = vnu.vnu_unit;
256 			close(vd);
257 			return (0);
258 		}
259 		vnu.vnu_unit++;
260 		goto query;
261 	}
262 
263 	fprintf(stdout, "vnd%d: ", vnu.vnu_unit);
264 
265 	if (!vnu.vnu_ino)
266 		fprintf(stdout, "not in use\n");
267 	else
268 		fprintf(stdout, "covering %s on %s, inode %llu\n",
269 		    vnu.vnu_file, devname(vnu.vnu_dev, S_IFBLK),
270 		    (unsigned long long)vnu.vnu_ino);
271 
272 	if (print_all) {
273 		vnu.vnu_unit++;
274 		goto query;
275 	}
276 
277 end:
278 	close(vd);
279 	if (availp)
280 		return (-1);
281 	return (0);
282 }
283 
284 int
285 config(char *file, char *dev, struct disklabel *dp, char *key, size_t keylen)
286 {
287 	struct vnd_ioctl vndio;
288 	char *rdev;
289 	int fd, rv = -1;
290 	int unit;
291 
292 	if (dev == NULL) {
293 		if (getinfo(NULL, &unit) == -1)
294 			err(1, "no devices available");
295 		printf("vnd%d\n", unit);
296 		asprintf(&dev, "vnd%d", unit);
297 	}
298 
299 	if ((fd = opendev(dev, O_RDONLY, OPENDEV_PART, &rdev)) == -1) {
300 		err(4, "%s", rdev);
301 		goto out;
302 	}
303 
304 	memset(&vndio, 0, sizeof vndio);
305 	vndio.vnd_file = file;
306 	vndio.vnd_secsize = (dp && dp->d_secsize) ? dp->d_secsize : DEV_BSIZE;
307 	vndio.vnd_nsectors = (dp && dp->d_nsectors) ? dp->d_nsectors : 100;
308 	vndio.vnd_ntracks = (dp && dp->d_ntracks) ? dp->d_ntracks : 1;
309 	vndio.vnd_key = (u_char *)key;
310 	vndio.vnd_keylen = keylen;
311 
312 	/*
313 	 * Configure the device
314 	 */
315 	rv = ioctl(fd, VNDIOCSET, &vndio);
316 	if (rv)
317 		warn("VNDIOCSET");
318 	else if (verbose)
319 		fprintf(stderr, "%s: %llu bytes on %s\n", dev, vndio.vnd_size,
320 		    file);
321 
322 	close(fd);
323 	fflush(stdout);
324  out:
325 	if (key)
326 		explicit_bzero(key, keylen);
327 	explicit_bzero(&vndio.vnd_keylen, sizeof vndio.vnd_keylen);
328 	return (rv == -1);
329 }
330 
331 int
332 unconfig(char *vnd)
333 {
334 	struct vnd_ioctl vndio;
335 	int fd, rv = -1;
336 	char *rdev;
337 
338 	if ((fd = opendev(vnd, O_RDONLY, OPENDEV_PART, &rdev)) == -1)
339 		err(4, "%s", rdev);
340 
341 	memset(&vndio, 0, sizeof vndio);
342 	vndio.vnd_file = vnd;
343 
344 	/*
345 	 * Clear (un-configure) the device
346 	 */
347 	rv = ioctl(fd, VNDIOCCLR, &vndio);
348 	if (rv)
349 		warn("VNDIOCCLR");
350 	else if (verbose)
351 		fprintf(stderr, "%s: cleared\n", vnd);
352 
353 	close(fd);
354 	fflush(stdout);
355 	return (rv == -1);
356 }
357 
358 __dead void
359 usage(void)
360 {
361 	fprintf(stderr,
362 	    "usage: vnconfig [-kv] [-K rounds] [-S saltfile] "
363 	    "[-t disktype] [vnd_dev] image\n");
364 	fprintf(stderr,
365 	    "       vnconfig -l [vnd_dev]\n");
366 	fprintf(stderr,
367 	    "       vnconfig -u [-v] vnd_dev\n");
368 	exit(1);
369 }
370