xref: /netbsd-src/usr.sbin/fstyp/hammer2.c (revision d90047b5d07facf36e6c01dcc0bded8997ce9cc2)
1 /*        $NetBSD: hammer2.c,v 1.4 2020/01/15 15:32:05 tkusumi Exp $      */
2 
3 /*-
4  * Copyright (c) 2017-2019 The DragonFly Project
5  * Copyright (c) 2017-2019 Tomohiro Kusumi <tkusumi@netbsd.org>
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: hammer2.c,v 1.4 2020/01/15 15:32:05 tkusumi Exp $");
31 
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <stdbool.h>
35 #include <string.h>
36 #include <err.h>
37 #include <assert.h>
38 
39 #include "fstyp.h"
40 #include "hammer2_disk.h"
41 
42 static hammer2_volume_data_t*
43 read_voldata(FILE *fp)
44 {
45 	hammer2_volume_data_t *voldata;
46 
47 	voldata = read_buf(fp, 0, sizeof(*voldata));
48 	if (voldata == NULL)
49 		err(1, "failed to read volume data");
50 
51 	return (voldata);
52 }
53 
54 static int
55 test_voldata(const hammer2_volume_data_t *voldata)
56 {
57 	if (voldata->magic != HAMMER2_VOLUME_ID_HBO &&
58 	    voldata->magic != HAMMER2_VOLUME_ID_ABO)
59 		return (1);
60 
61 	return (0);
62 }
63 
64 static hammer2_media_data_t*
65 read_media(FILE *fp, const hammer2_blockref_t *bref, size_t *media_bytes)
66 {
67 	hammer2_media_data_t *media;
68 	hammer2_off_t io_off, io_base;
69 	size_t bytes, io_bytes, boff;
70 
71 	bytes = (bref->data_off & HAMMER2_OFF_MASK_RADIX);
72 	if (bytes)
73 		bytes = (size_t)1 << bytes;
74 	*media_bytes = bytes;
75 
76 	if (!bytes) {
77 		warnx("blockref has no data");
78 		return (NULL);
79 	}
80 
81 	io_off = bref->data_off & ~HAMMER2_OFF_MASK_RADIX;
82 	io_base = io_off & ~(hammer2_off_t)(HAMMER2_MINIOSIZE - 1);
83 	boff = (size_t)(io_off - io_base);
84 
85 	io_bytes = HAMMER2_MINIOSIZE;
86 	while (io_bytes + boff < bytes)
87 		io_bytes <<= 1;
88 
89 	if (io_bytes > sizeof(hammer2_media_data_t)) {
90 		warnx("invalid I/O bytes");
91 		return (NULL);
92 	}
93 
94 	if (fseek(fp, (long int)io_base, SEEK_SET) == -1) {
95 		warnx("failed to seek media");
96 		return (NULL);
97 	}
98 	media = read_buf(fp, (off_t)io_base, io_bytes);
99 	if (media == NULL) {
100 		warnx("failed to read media");
101 		return (NULL);
102 	}
103 	if (boff)
104 		memcpy(media, (char *)media + boff, bytes);
105 
106 	return (media);
107 }
108 
109 static int
110 find_pfs(FILE *fp, const hammer2_blockref_t *bref, const char *pfs, bool *res)
111 {
112 	hammer2_media_data_t *media;
113 	hammer2_inode_data_t ipdata;
114 	hammer2_blockref_t *bscan;
115 	size_t bytes;
116 	int i, bcount;
117 
118 	media = read_media(fp, bref, &bytes);
119 	if (media == NULL)
120 		return (-1);
121 
122 	switch (bref->type) {
123 	case HAMMER2_BREF_TYPE_INODE:
124 		ipdata = media->ipdata;
125 		if (ipdata.meta.pfs_type & HAMMER2_PFSTYPE_SUPROOT) {
126 			bscan = &ipdata.u.blockset.blockref[0];
127 			bcount = HAMMER2_SET_COUNT;
128 		} else {
129 			bscan = NULL;
130 			bcount = 0;
131 			if (ipdata.meta.op_flags & HAMMER2_OPFLAG_PFSROOT) {
132 				if (memchr(ipdata.filename, 0,
133 				    sizeof(ipdata.filename))) {
134 					if (!strcmp(
135 					    (const char*)ipdata.filename, pfs))
136 						*res = true;
137 				} else {
138 					if (strlen(pfs) > 0 &&
139 					    !memcmp(ipdata.filename, pfs,
140 					    strlen(pfs)))
141 						*res = true;
142 				}
143 			} else
144 				assert(0);
145 		}
146 		break;
147 	case HAMMER2_BREF_TYPE_INDIRECT:
148 		bscan = &media->npdata[0];
149 		bcount = (int)(bytes / sizeof(hammer2_blockref_t));
150 		break;
151 	default:
152 		bscan = NULL;
153 		bcount = 0;
154 		break;
155 	}
156 
157 	for (i = 0; i < bcount; ++i) {
158 		if (bscan[i].type != HAMMER2_BREF_TYPE_EMPTY) {
159 			if (find_pfs(fp, &bscan[i], pfs, res) == -1) {
160 				free(media);
161 				return (-1);
162 			}
163 		}
164 	}
165 	free(media);
166 
167 	return (0);
168 }
169 
170 static char*
171 extract_device_name(const char *devpath)
172 {
173 	char *p, *head;
174 
175 	if (!devpath)
176 		return NULL;
177 
178 	p = strdup(devpath);
179 	head = p;
180 
181 	p = strchr(p, '@');
182 	if (p)
183 		*p = 0;
184 
185 	p = strrchr(head, '/');
186 	if (p) {
187 		p++;
188 		if (*p == 0) {
189 			free(head);
190 			return NULL;
191 		}
192 		p = strdup(p);
193 		free(head);
194 		return p;
195 	}
196 
197 	return head;
198 }
199 
200 static int
201 read_label(FILE *fp, char *label, size_t size)
202 {
203 	hammer2_blockref_t broot, best, *bref;
204 	hammer2_media_data_t *vols[HAMMER2_NUM_VOLHDRS], *media;
205 	size_t bytes;
206 	bool res = false;
207 	int i, best_i, error = 1;
208 	const char *pfs;
209 	char *devname;
210 
211 	best_i = -1;
212 	memset(&best, 0, sizeof(best));
213 
214 	for (i = 0; i < HAMMER2_NUM_VOLHDRS; i++) {
215 		memset(&broot, 0, sizeof(broot));
216 		broot.type = HAMMER2_BREF_TYPE_VOLUME;
217 		broot.data_off = ((hammer2_off_t)i *
218 		    (hammer2_off_t)HAMMER2_ZONE_BYTES64) | HAMMER2_PBUFRADIX;
219 		vols[i] = read_buf(fp,
220 		    (off_t)(broot.data_off & ~HAMMER2_OFF_MASK_RADIX),
221 		    sizeof(*vols[i]));
222 		broot.mirror_tid = vols[i]->voldata.mirror_tid;
223 		if (best_i < 0 || best.mirror_tid < broot.mirror_tid) {
224 			best_i = i;
225 			best = broot;
226 		}
227 	}
228 
229 	bref = &vols[best_i]->voldata.sroot_blockset.blockref[0];
230 	if (bref->type != HAMMER2_BREF_TYPE_INODE) {
231 		warnx("blockref type is not inode");
232 		goto fail;
233 	}
234 
235 	media = read_media(fp, bref, &bytes);
236 	if (media == NULL) {
237 		goto fail;
238 	}
239 
240 	/*
241 	 * fstyp_function in DragonFly takes an additional devpath argument
242 	 * which doesn't exist in FreeBSD and NetBSD.
243 	 */
244 #ifdef HAS_DEVPATH
245 	pfs = strchr(devpath, '@');
246 	if (!pfs) {
247 		assert(strlen(devpath));
248 		switch (devpath[strlen(devpath) - 1]) {
249 		case 'a':
250 			pfs = "BOOT";
251 			break;
252 		case 'd':
253 			pfs = "ROOT";
254 			break;
255 		default:
256 			pfs = "DATA";
257 			break;
258 		}
259 	} else
260 		pfs++;
261 
262 	if (strlen(pfs) > HAMMER2_INODE_MAXNAME) {
263 		goto fail;
264 	}
265 	devname = extract_device_name(devpath);
266 #else
267 	pfs = "";
268 	devname = extract_device_name(NULL);
269 	assert(!devname);
270 #endif
271 
272 	/* Add device name to help support multiple autofs -media mounts. */
273 	if (find_pfs(fp, bref, pfs, &res) == 0 && res) {
274 		if (devname)
275 			snprintf(label, size, "%s_%s", pfs, devname);
276 		else
277 			strlcpy(label, pfs, size);
278 	} else {
279 		memset(label, 0, size);
280 		memcpy(label, media->ipdata.filename,
281 		    sizeof(media->ipdata.filename));
282 		if (devname) {
283 			strlcat(label, "_", size);
284 			strlcat(label, devname, size);
285 		}
286 	}
287 	if (devname)
288 		free(devname);
289 	free(media);
290 	error = 0;
291 fail:
292 	for (i = 0; i < HAMMER2_NUM_VOLHDRS; i++)
293 		free(vols[i]);
294 
295 	return (error);
296 }
297 
298 int
299 fstyp_hammer2(FILE *fp, char *label, size_t size)
300 {
301 	hammer2_volume_data_t *voldata;
302 	int error = 1;
303 
304 	voldata = read_voldata(fp);
305 	if (test_voldata(voldata))
306 		goto fail;
307 
308 	error = read_label(fp, label, size);
309 fail:
310 	free(voldata);
311 	return (error);
312 }
313