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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	sbin/fdisk/mbr.c	Lines:	0	113	0.0 %
Date:	2016-12-06	Branches:	0	48	0.0 %


/*	$OpenBSD: mbr.c,v 1.65 2015/12/30 17:21:39 krw Exp $	*/

/*
 * Copyright (c) 1997 Tobias Weingartner
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/param.h>	/* DEV_BSIZE */
#include <sys/ioctl.h>
#include <sys/disklabel.h>
#include <sys/dkio.h>

#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "disk.h"
#include "part.h"
#include "misc.h"
#include "mbr.h"
#include "gpt.h"

struct mbr initial_mbr;

static int gpt_chk_mbr(struct dos_partition *, u_int64_t);

int
MBR_protective_mbr(struct mbr *mbr)
{
	struct dos_partition dp[NDOSPART], dos_partition;
	int i;

	for (i = 0; i < NDOSPART; i++) {
		PRT_make(&mbr->part[i], mbr->offset, mbr->reloffset,
		    &dos_partition);
		memcpy(&dp[i], &dos_partition, sizeof(dp[i]));
	}

	return (gpt_chk_mbr(dp, DL_GETDSIZE(&dl)));
}

void
MBR_init_GPT(struct mbr *mbr)
{
	u_int64_t sz;

	sz = DL_GETDSIZE(&dl);

	memset(&mbr->part, 0, sizeof(mbr->part));

	/* Use whole disk, starting after MBR. */
	mbr->part[0].id = DOSPTYP_EFI;
	mbr->part[0].bs = 1;
	if (sz > UINT32_MAX)
		mbr->part[0].ns = UINT32_MAX;
	else
		mbr->part[0].ns = sz - 1;

	/* Fix up start/length fields. */
	PRT_fix_CHS(&mbr->part[0]);
}

void
MBR_init(struct mbr *mbr)
{
	extern u_int32_t b_arg;
	u_int64_t adj;
	daddr_t i;

	/*
	 * XXX Do *NOT* zap all MBR parts! Some archs still read initmbr
	 * from disk!! Just mark them inactive until -b goodness spreads
	 * further.
	 */
	mbr->part[0].flag = 0;
	mbr->part[1].flag = 0;
	mbr->part[2].flag = 0;

	memset(&gh, 0, sizeof(gh));
	memset(&gp, 0, sizeof(gp));

	mbr->part[3].flag = DOSACTIVE;
	mbr->signature = DOSMBR_SIGNATURE;

	/* Use whole disk. Reserve first track, or first cyl, if possible. */
	mbr->part[3].id = DOSPTYP_OPENBSD;
	if (disk.heads > 1)
		mbr->part[3].shead = 1;
	else
		mbr->part[3].shead = 0;
	if (disk.heads < 2 && disk.cylinders > 1)
		mbr->part[3].scyl = 1;
	else
		mbr->part[3].scyl = 0;
	mbr->part[3].ssect = 1;

	/* Go right to the end */
	mbr->part[3].ecyl = disk.cylinders - 1;
	mbr->part[3].ehead = disk.heads - 1;
	mbr->part[3].esect = disk.sectors;

	/* Fix up start/length fields */
	PRT_fix_BN(&mbr->part[3], 3);

#if defined(__powerpc__) || defined(__mips__)
	/* Now fix up for the MS-DOS boot partition on PowerPC. */
	mbr->part[0].flag = DOSACTIVE;	/* Boot from dos part */
	mbr->part[3].flag = 0;
	mbr->part[3].ns += mbr->part[3].bs;
	mbr->part[3].bs = mbr->part[0].bs + mbr->part[0].ns;
	mbr->part[3].ns -= mbr->part[3].bs;
	PRT_fix_CHS(&mbr->part[3]);
	if ((mbr->part[3].shead != 1) || (mbr->part[3].ssect != 1)) {
		/* align the partition on a cylinder boundary */
		mbr->part[3].shead = 0;
		mbr->part[3].ssect = 1;
		mbr->part[3].scyl += 1;
	}
	/* Fix up start/length fields */
	PRT_fix_BN(&mbr->part[3], 3);
#endif
#if defined(__i386__) || defined(__amd64__)
	if (b_arg > 0) {
		/* Add an EFI system partition on i386/amd64. */
		mbr->part[0].id = DOSPTYP_EFISYS;
		mbr->part[0].bs = 64;
		mbr->part[0].ns = b_arg;
		PRT_fix_CHS(&mbr->part[0]);
		mbr->part[3].ns += mbr->part[3].bs;
		mbr->part[3].bs = mbr->part[0].bs + mbr->part[0].ns;
		mbr->part[3].ns -= mbr->part[3].bs;
		PRT_fix_CHS(&mbr->part[3]);
	}
#endif

	/* Start OpenBSD MBR partition on a power of 2 block number. */
	i = 1;
	while (i < DL_SECTOBLK(&dl, mbr->part[3].bs))
		i *= 2;
	adj = DL_BLKTOSEC(&dl, i) - mbr->part[3].bs;
	mbr->part[3].bs += adj;
	mbr->part[3].ns -= adj;
	PRT_fix_CHS(&mbr->part[3]);
}

void
MBR_parse(struct dos_mbr *dos_mbr, off_t offset, off_t reloff, struct mbr *mbr)
{
	struct dos_partition dos_parts[NDOSPART];
	int i;

	memcpy(mbr->code, dos_mbr->dmbr_boot, sizeof(mbr->code));
	mbr->offset = offset;
	mbr->reloffset = reloff;
	mbr->signature = letoh16(dos_mbr->dmbr_sign);

	memcpy(dos_parts, dos_mbr->dmbr_parts, sizeof(dos_parts));

	for (i = 0; i < NDOSPART; i++)
		PRT_parse(&dos_parts[i], offset, reloff, &mbr->part[i]);
}

void
MBR_make(struct mbr *mbr, struct dos_mbr *dos_mbr)
{
	struct dos_partition dos_partition;
	int i;

	memcpy(dos_mbr->dmbr_boot, mbr->code, sizeof(dos_mbr->dmbr_boot));
	dos_mbr->dmbr_sign = htole16(DOSMBR_SIGNATURE);

	for (i = 0; i < NDOSPART; i++) {
		PRT_make(&mbr->part[i], mbr->offset, mbr->reloffset,
		    &dos_partition);
		memcpy(&dos_mbr->dmbr_parts[i], &dos_partition,
		    sizeof(dos_mbr->dmbr_parts[i]));
	}
}

void
MBR_print(struct mbr *mbr, char *units)
{
	int i;

	DISK_printgeometry(NULL);

	/* Header */
	printf("Offset: %lld\t", (long long)mbr->offset);
	printf("Signature: 0x%X\n", (int)mbr->signature);
	PRT_print(0, NULL, units);

	/* Entries */
	for (i = 0; i < NDOSPART; i++)
		PRT_print(i, &mbr->part[i], units);
}

int
MBR_read(off_t where, struct dos_mbr *dos_mbr)
{
	char *secbuf;

	secbuf = DISK_readsector(where);
	if (secbuf == NULL)
		return (-1);

	memcpy(dos_mbr, secbuf, sizeof(*dos_mbr));
	free(secbuf);

	return (0);
}

int
MBR_write(off_t where, struct dos_mbr *dos_mbr)
{
	char *secbuf;

	secbuf = DISK_readsector(where);
	if (secbuf == NULL)
		return (-1);

	/*
	 * Place the new MBR at the start of the sector and
	 * write the sector back to "disk".
	 */
	memcpy(secbuf, dos_mbr, sizeof(*dos_mbr));
	DISK_writesector(secbuf, where);

	/* Refresh in-kernel disklabel from the updated disk information. */
	ioctl(disk.fd, DIOCRLDINFO, 0);

	free(secbuf);

	return (0);
}

/*
 * If *dos_mbr has a 0xee or 0xef partition, nothing needs to happen. If no
 * such partition is present but the first or last sector on the disk has a
 * GPT, zero the GPT to ensure the MBR takes priority and fewer BIOSes get
 * confused.
 */
void
MBR_zapgpt(struct dos_mbr *dos_mbr, uint64_t lastsec)
{
	struct dos_partition dos_parts[NDOSPART];
	char *secbuf;
	uint64_t sig;
	int i;

	memcpy(dos_parts, dos_mbr->dmbr_parts, sizeof(dos_parts));

	for (i = 0; i < NDOSPART; i++)
		if ((dos_parts[i].dp_typ == DOSPTYP_EFI) ||
		    (dos_parts[i].dp_typ == DOSPTYP_EFISYS))
			return;

	secbuf = DISK_readsector(GPTSECTOR);
	if (secbuf == NULL)
		return;

	memcpy(&sig, secbuf, sizeof(sig));
	if (letoh64(sig) == GPTSIGNATURE) {
		memset(secbuf, 0, sizeof(sig));
		DISK_writesector(secbuf, GPTSECTOR);
	}
	free(secbuf);

	secbuf = DISK_readsector(lastsec);
	if (secbuf == NULL)
		return;

	memcpy(&sig, secbuf, sizeof(sig));
	if (letoh64(sig) == GPTSIGNATURE) {
		memset(secbuf, 0, sizeof(sig));
		DISK_writesector(secbuf, lastsec);
	}
	free(secbuf);
}

/*
 * Returns 0 if the MBR with the provided partition array is a GPT protective
 * MBR, and returns 1 otherwise. A GPT protective MBR would have one and only
 * one MBR partition, an EFI partition that either covers the whole disk or as
 * much of it as is possible with a 32bit size field.
 *
 * Taken from kern/subr_disk.c.
 *
 * NOTE: MS always uses a size of UINT32_MAX for the EFI partition!**
 */
int
gpt_chk_mbr(struct dos_partition *dp, u_int64_t dsize)
{
	struct dos_partition *dp2;
	int efi, found, i;
	u_int32_t psize;

	found = efi = 0;
	for (dp2=dp, i=0; i < NDOSPART; i++, dp2++) {
		if (dp2->dp_typ == DOSPTYP_UNUSED)
			continue;
		found++;
		if (dp2->dp_typ != DOSPTYP_EFI)
			continue;
		psize = letoh32(dp2->dp_size);
		if (psize == (dsize - 1) ||
		    psize == UINT32_MAX) {
			if (letoh32(dp2->dp_start) == 1)
				efi++;
		}
	}
	if (found == 1 && efi == 1)
		return (0);

	return (1);
}



Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: mbr.c,v 1.65 2015/12/30 17:21:39 krw Exp $ */
2
3			/*
4			* Copyright (c) 1997 Tobias Weingartner
5			*
6			* Permission to use, copy, modify, and distribute this software for any
7			* purpose with or without fee is hereby granted, provided that the above
8			* copyright notice and this permission notice appear in all copies.
9			*
10			* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11			* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12			* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13			* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15			* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16			* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17			*/
18
19			#include <sys/param.h> /* DEV_BSIZE */
20			#include <sys/ioctl.h>
21			#include <sys/disklabel.h>
22			#include <sys/dkio.h>
23
24			#include <stdint.h>
25			#include <stdio.h>
26			#include <stdlib.h>
27			#include <string.h>
28
29			#include "disk.h"
30			#include "part.h"
31			#include "misc.h"
32			#include "mbr.h"
33			#include "gpt.h"
34
35			struct mbr initial_mbr;
36
37			static int gpt_chk_mbr(struct dos_partition *, u_int64_t);
38
39			int
40			MBR_protective_mbr(struct mbr *mbr)
41			{
42			struct dos_partition dp[NDOSPART], dos_partition;
43			int i;
44
45			for (i = 0; i < NDOSPART; i++) {
46			PRT_make(&mbr->part[i], mbr->offset, mbr->reloffset,
47			&dos_partition);
48			memcpy(&dp[i], &dos_partition, sizeof(dp[i]));
49			}
50
51			return (gpt_chk_mbr(dp, DL_GETDSIZE(&dl)));
52			}
53
54			void
55			MBR_init_GPT(struct mbr *mbr)
56			{
57			u_int64_t sz;
58
59			sz = DL_GETDSIZE(&dl);
60
61			memset(&mbr->part, 0, sizeof(mbr->part));
62
63			/* Use whole disk, starting after MBR. */
64			mbr->part[0].id = DOSPTYP_EFI;
65			mbr->part[0].bs = 1;
66			if (sz > UINT32_MAX)
67			mbr->part[0].ns = UINT32_MAX;
68			else
69			mbr->part[0].ns = sz - 1;
70
71			/* Fix up start/length fields. */
72			PRT_fix_CHS(&mbr->part[0]);
73			}
74
75			void
76			MBR_init(struct mbr *mbr)
77			{
78			extern u_int32_t b_arg;
79			u_int64_t adj;
80			daddr_t i;
81
82			/*
83			* XXX Do NOT zap all MBR parts! Some archs still read initmbr
84			* from disk!! Just mark them inactive until -b goodness spreads
85			* further.
86			*/
87			mbr->part[0].flag = 0;
88			mbr->part[1].flag = 0;
89			mbr->part[2].flag = 0;
90
91			memset(&gh, 0, sizeof(gh));
92			memset(&gp, 0, sizeof(gp));
93
94			mbr->part[3].flag = DOSACTIVE;
95			mbr->signature = DOSMBR_SIGNATURE;
96
97			/* Use whole disk. Reserve first track, or first cyl, if possible. */
98			mbr->part[3].id = DOSPTYP_OPENBSD;
99			if (disk.heads > 1)
100			mbr->part[3].shead = 1;
101			else
102			mbr->part[3].shead = 0;
103			if (disk.heads < 2 && disk.cylinders > 1)
104			mbr->part[3].scyl = 1;
105			else
106			mbr->part[3].scyl = 0;
107			mbr->part[3].ssect = 1;
108
109			/* Go right to the end */
110			mbr->part[3].ecyl = disk.cylinders - 1;
111			mbr->part[3].ehead = disk.heads - 1;
112			mbr->part[3].esect = disk.sectors;
113
114			/* Fix up start/length fields */
115			PRT_fix_BN(&mbr->part[3], 3);
116
117			#if defined(__powerpc__) \|\| defined(__mips__)
118			/* Now fix up for the MS-DOS boot partition on PowerPC. */
119			mbr->part[0].flag = DOSACTIVE; /* Boot from dos part */
120			mbr->part[3].flag = 0;
121			mbr->part[3].ns += mbr->part[3].bs;
122			mbr->part[3].bs = mbr->part[0].bs + mbr->part[0].ns;
123			mbr->part[3].ns -= mbr->part[3].bs;
124			PRT_fix_CHS(&mbr->part[3]);
125			if ((mbr->part[3].shead != 1) \|\| (mbr->part[3].ssect != 1)) {
126			/* align the partition on a cylinder boundary */
127			mbr->part[3].shead = 0;
128			mbr->part[3].ssect = 1;
129			mbr->part[3].scyl += 1;
130			}
131			/* Fix up start/length fields */
132			PRT_fix_BN(&mbr->part[3], 3);
133			#endif
134			#if defined(__i386__) \|\| defined(__amd64__)
135			if (b_arg > 0) {
136			/* Add an EFI system partition on i386/amd64. */
137			mbr->part[0].id = DOSPTYP_EFISYS;
138			mbr->part[0].bs = 64;
139			mbr->part[0].ns = b_arg;
140			PRT_fix_CHS(&mbr->part[0]);
141			mbr->part[3].ns += mbr->part[3].bs;
142			mbr->part[3].bs = mbr->part[0].bs + mbr->part[0].ns;
143			mbr->part[3].ns -= mbr->part[3].bs;
144			PRT_fix_CHS(&mbr->part[3]);
145			}
146			#endif
147
148			/* Start OpenBSD MBR partition on a power of 2 block number. */
149			i = 1;
150			while (i < DL_SECTOBLK(&dl, mbr->part[3].bs))
151			i *= 2;
152			adj = DL_BLKTOSEC(&dl, i) - mbr->part[3].bs;
153			mbr->part[3].bs += adj;
154			mbr->part[3].ns -= adj;
155			PRT_fix_CHS(&mbr->part[3]);
156			}
157
158			void
159			MBR_parse(struct dos_mbr dos_mbr, off_t offset, off_t reloff, struct mbr mbr)
160			{
161			struct dos_partition dos_parts[NDOSPART];
162			int i;
163
164			memcpy(mbr->code, dos_mbr->dmbr_boot, sizeof(mbr->code));
165			mbr->offset = offset;
166			mbr->reloffset = reloff;
167			mbr->signature = letoh16(dos_mbr->dmbr_sign);
168
169			memcpy(dos_parts, dos_mbr->dmbr_parts, sizeof(dos_parts));
170
171			for (i = 0; i < NDOSPART; i++)
172			PRT_parse(&dos_parts[i], offset, reloff, &mbr->part[i]);
173			}
174
175			void
176			MBR_make(struct mbr mbr, struct dos_mbr dos_mbr)
177			{
178			struct dos_partition dos_partition;
179			int i;
180
181			memcpy(dos_mbr->dmbr_boot, mbr->code, sizeof(dos_mbr->dmbr_boot));
182			dos_mbr->dmbr_sign = htole16(DOSMBR_SIGNATURE);
183
184			for (i = 0; i < NDOSPART; i++) {
185			PRT_make(&mbr->part[i], mbr->offset, mbr->reloffset,
186			&dos_partition);
187			memcpy(&dos_mbr->dmbr_parts[i], &dos_partition,
188			sizeof(dos_mbr->dmbr_parts[i]));
189			}
190			}
191
192			void
193			MBR_print(struct mbr mbr, char units)
194			{
195			int i;
196
197			DISK_printgeometry(NULL);
198
199			/* Header */
200			printf("Offset: %lld\t", (long long)mbr->offset);
201			printf("Signature: 0x%X\n", (int)mbr->signature);
202			PRT_print(0, NULL, units);
203
204			/* Entries */
205			for (i = 0; i < NDOSPART; i++)
206			PRT_print(i, &mbr->part[i], units);
207			}
208
209			int
210			MBR_read(off_t where, struct dos_mbr *dos_mbr)
211			{
212			char *secbuf;
213
214			secbuf = DISK_readsector(where);
215			if (secbuf == NULL)
216			return (-1);
217
218			memcpy(dos_mbr, secbuf, sizeof(*dos_mbr));
219			free(secbuf);
220
221			return (0);
222			}
223
224			int
225			MBR_write(off_t where, struct dos_mbr *dos_mbr)
226			{
227			char *secbuf;
228
229			secbuf = DISK_readsector(where);
230			if (secbuf == NULL)
231			return (-1);
232
233			/*
234			* Place the new MBR at the start of the sector and
235			* write the sector back to "disk".
236			*/
237			memcpy(secbuf, dos_mbr, sizeof(*dos_mbr));
238			DISK_writesector(secbuf, where);
239
240			/* Refresh in-kernel disklabel from the updated disk information. */
241			ioctl(disk.fd, DIOCRLDINFO, 0);
242
243			free(secbuf);
244
245			return (0);
246			}
247
248			/*
249			* If *dos_mbr has a 0xee or 0xef partition, nothing needs to happen. If no
250			* such partition is present but the first or last sector on the disk has a
251			* GPT, zero the GPT to ensure the MBR takes priority and fewer BIOSes get
252			* confused.
253			*/
254			void
255			MBR_zapgpt(struct dos_mbr *dos_mbr, uint64_t lastsec)
256			{
257			struct dos_partition dos_parts[NDOSPART];
258			char *secbuf;
259			uint64_t sig;
260			int i;
261
262			memcpy(dos_parts, dos_mbr->dmbr_parts, sizeof(dos_parts));
263
264			for (i = 0; i < NDOSPART; i++)
265			if ((dos_parts[i].dp_typ == DOSPTYP_EFI) \|\|
266			(dos_parts[i].dp_typ == DOSPTYP_EFISYS))
267			return;
268
269			secbuf = DISK_readsector(GPTSECTOR);
270			if (secbuf == NULL)
271			return;
272
273			memcpy(&sig, secbuf, sizeof(sig));
274			if (letoh64(sig) == GPTSIGNATURE) {
275			memset(secbuf, 0, sizeof(sig));
276			DISK_writesector(secbuf, GPTSECTOR);
277			}
278			free(secbuf);
279
280			secbuf = DISK_readsector(lastsec);
281			if (secbuf == NULL)
282			return;
283
284			memcpy(&sig, secbuf, sizeof(sig));
285			if (letoh64(sig) == GPTSIGNATURE) {
286			memset(secbuf, 0, sizeof(sig));
287			DISK_writesector(secbuf, lastsec);
288			}
289			free(secbuf);
290			}
291
292			/*
293			* Returns 0 if the MBR with the provided partition array is a GPT protective
294			* MBR, and returns 1 otherwise. A GPT protective MBR would have one and only
295			* one MBR partition, an EFI partition that either covers the whole disk or as
296			* much of it as is possible with a 32bit size field.
297			*
298			* Taken from kern/subr_disk.c.
299			*
300			* NOTE: MS always uses a size of UINT32_MAX for the EFI partition!**
301			*/
302			int
303			gpt_chk_mbr(struct dos_partition *dp, u_int64_t dsize)
304			{
305			struct dos_partition *dp2;
306			int efi, found, i;
307			u_int32_t psize;
308
309			found = efi = 0;
310			for (dp2=dp, i=0; i < NDOSPART; i++, dp2++) {
311			if (dp2->dp_typ == DOSPTYP_UNUSED)
312			continue;
313			found++;
314			if (dp2->dp_typ != DOSPTYP_EFI)
315			continue;
316			psize = letoh32(dp2->dp_size);
317			if (psize == (dsize - 1) \|\|
318			psize == UINT32_MAX) {
319			if (letoh32(dp2->dp_start) == 1)
320			efi++;
321			}
322			}
323			if (found == 1 && efi == 1)
324			return (0);
325
326			return (1);
327			}
328