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