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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	sbin/fdisk/mbr.c	Lines:	0	108	0.0 %
Date:	2017-11-07	Branches:	0	42	0.0 %


/*	$OpenBSD: mbr.c,v 1.67 2016/09/01 16:17:46 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)
{
	memset(&mbr->part, 0, sizeof(mbr->part));

	/* Use whole disk, starting after MBR.
	 *
	 * Always set the partition size to UINT32_MAX (as MS does). EFI
	 * firmware has been encountered that lies in unpredictable ways
	 * about the size of the disk, thus making it impossible to boot
	 * such devices.
	 */
	mbr->part[0].id = DOSPTYP_EFI;
	mbr->part[0].bs = 1;
	mbr->part[0].ns = UINT32_MAX;

	/* 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 1.67 2016/09/01 16:17:46 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			memset(&mbr->part, 0, sizeof(mbr->part));
58
59			/* Use whole disk, starting after MBR.
60			*
61			* Always set the partition size to UINT32_MAX (as MS does). EFI
62			* firmware has been encountered that lies in unpredictable ways
63			* about the size of the disk, thus making it impossible to boot
64			* such devices.
65			*/
66			mbr->part[0].id = DOSPTYP_EFI;
67			mbr->part[0].bs = 1;
68			mbr->part[0].ns = UINT32_MAX;
69
70			/* Fix up start/length fields. */
71			PRT_fix_CHS(&mbr->part[0]);
72			}
73
74			void
75			MBR_init(struct mbr *mbr)
76			{
77			extern u_int32_t b_arg;
78			u_int64_t adj;
79			daddr_t i;
80
81			/*
82			* XXX Do NOT zap all MBR parts! Some archs still read initmbr
83			* from disk!! Just mark them inactive until -b goodness spreads
84			* further.
85			*/
86			mbr->part[0].flag = 0;
87			mbr->part[1].flag = 0;
88			mbr->part[2].flag = 0;
89
90			memset(&gh, 0, sizeof(gh));
91			memset(&gp, 0, sizeof(gp));
92
93			mbr->part[3].flag = DOSACTIVE;
94			mbr->signature = DOSMBR_SIGNATURE;
95
96			/* Use whole disk. Reserve first track, or first cyl, if possible. */
97			mbr->part[3].id = DOSPTYP_OPENBSD;
98			if (disk.heads > 1)
99			mbr->part[3].shead = 1;
100			else
101			mbr->part[3].shead = 0;
102			if (disk.heads < 2 && disk.cylinders > 1)
103			mbr->part[3].scyl = 1;
104			else
105			mbr->part[3].scyl = 0;
106			mbr->part[3].ssect = 1;
107
108			/* Go right to the end */
109			mbr->part[3].ecyl = disk.cylinders - 1;
110			mbr->part[3].ehead = disk.heads - 1;
111			mbr->part[3].esect = disk.sectors;
112
113			/* Fix up start/length fields */
114			PRT_fix_BN(&mbr->part[3], 3);
115
116			#if defined(__powerpc__) \|\| defined(__mips__)
117			/* Now fix up for the MS-DOS boot partition on PowerPC. */
118			mbr->part[0].flag = DOSACTIVE; /* Boot from dos part */
119			mbr->part[3].flag = 0;
120			mbr->part[3].ns += mbr->part[3].bs;
121			mbr->part[3].bs = mbr->part[0].bs + mbr->part[0].ns;
122			mbr->part[3].ns -= mbr->part[3].bs;
123			PRT_fix_CHS(&mbr->part[3]);
124			if ((mbr->part[3].shead != 1) \|\| (mbr->part[3].ssect != 1)) {
125			/* align the partition on a cylinder boundary */
126			mbr->part[3].shead = 0;
127			mbr->part[3].ssect = 1;
128			mbr->part[3].scyl += 1;
129			}
130			/* Fix up start/length fields */
131			PRT_fix_BN(&mbr->part[3], 3);
132			#endif
133			#if defined(__i386__) \|\| defined(__amd64__)
134			if (b_arg > 0) {
135			/* Add an EFI system partition on i386/amd64. */
136			mbr->part[0].id = DOSPTYP_EFISYS;
137			mbr->part[0].bs = 64;
138			mbr->part[0].ns = b_arg;
139			PRT_fix_CHS(&mbr->part[0]);
140			mbr->part[3].ns += mbr->part[3].bs;
141			mbr->part[3].bs = mbr->part[0].bs + mbr->part[0].ns;
142			mbr->part[3].ns -= mbr->part[3].bs;
143			PRT_fix_CHS(&mbr->part[3]);
144			}
145			#endif
146
147			/* Start OpenBSD MBR partition on a power of 2 block number. */
148			i = 1;
149			while (i < DL_SECTOBLK(&dl, mbr->part[3].bs))
150			i *= 2;
151			adj = DL_BLKTOSEC(&dl, i) - mbr->part[3].bs;
152			mbr->part[3].bs += adj;
153			mbr->part[3].ns -= adj;
154			PRT_fix_CHS(&mbr->part[3]);
155			}
156
157			void
158			MBR_parse(struct dos_mbr dos_mbr, off_t offset, off_t reloff, struct mbr mbr)
159			{
160			struct dos_partition dos_parts[NDOSPART];
161			int i;
162
163			memcpy(mbr->code, dos_mbr->dmbr_boot, sizeof(mbr->code));
164			mbr->offset = offset;
165			mbr->reloffset = reloff;
166			mbr->signature = letoh16(dos_mbr->dmbr_sign);
167
168			memcpy(dos_parts, dos_mbr->dmbr_parts, sizeof(dos_parts));
169
170			for (i = 0; i < NDOSPART; i++)
171			PRT_parse(&dos_parts[i], offset, reloff, &mbr->part[i]);
172			}
173
174			void
175			MBR_make(struct mbr mbr, struct dos_mbr dos_mbr)
176			{
177			struct dos_partition dos_partition;
178			int i;
179
180			memcpy(dos_mbr->dmbr_boot, mbr->code, sizeof(dos_mbr->dmbr_boot));
181			dos_mbr->dmbr_sign = htole16(DOSMBR_SIGNATURE);
182
183			for (i = 0; i < NDOSPART; i++) {
184			PRT_make(&mbr->part[i], mbr->offset, mbr->reloffset,
185			&dos_partition);
186			memcpy(&dos_mbr->dmbr_parts[i], &dos_partition,
187			sizeof(dos_mbr->dmbr_parts[i]));
188			}
189			}
190
191			void
192			MBR_print(struct mbr mbr, char units)
193			{
194			int i;
195
196			DISK_printgeometry(NULL);
197
198			/* Header */
199			printf("Offset: %lld\t", (long long)mbr->offset);
200			printf("Signature: 0x%X\n", (int)mbr->signature);
201			PRT_print(0, NULL, units);
202
203			/* Entries */
204			for (i = 0; i < NDOSPART; i++)
205			PRT_print(i, &mbr->part[i], units);
206			}
207
208			int
209			MBR_read(off_t where, struct dos_mbr *dos_mbr)
210			{
211			char *secbuf;
212
213			secbuf = DISK_readsector(where);
214			if (secbuf == NULL)
215			return (-1);
216
217			memcpy(dos_mbr, secbuf, sizeof(*dos_mbr));
218			free(secbuf);
219
220			return (0);
221			}
222
223			int
224			MBR_write(off_t where, struct dos_mbr *dos_mbr)
225			{
226			char *secbuf;
227
228			secbuf = DISK_readsector(where);
229			if (secbuf == NULL)
230			return (-1);
231
232			/*
233			* Place the new MBR at the start of the sector and
234			* write the sector back to "disk".
235			*/
236			memcpy(secbuf, dos_mbr, sizeof(*dos_mbr));
237			DISK_writesector(secbuf, where);
238
239			/* Refresh in-kernel disklabel from the updated disk information. */
240			ioctl(disk.fd, DIOCRLDINFO, 0);
241
242			free(secbuf);
243
244			return (0);
245			}
246
247			/*
248			* If *dos_mbr has a 0xee or 0xef partition, nothing needs to happen. If no
249			* such partition is present but the first or last sector on the disk has a
250			* GPT, zero the GPT to ensure the MBR takes priority and fewer BIOSes get
251			* confused.
252			*/
253			void
254			MBR_zapgpt(struct dos_mbr *dos_mbr, uint64_t lastsec)
255			{
256			struct dos_partition dos_parts[NDOSPART];
257			char *secbuf;
258			uint64_t sig;
259			int i;
260
261			memcpy(dos_parts, dos_mbr->dmbr_parts, sizeof(dos_parts));
262
263			for (i = 0; i < NDOSPART; i++)
264			if ((dos_parts[i].dp_typ == DOSPTYP_EFI) \|\|
265			(dos_parts[i].dp_typ == DOSPTYP_EFISYS))
266			return;
267
268			secbuf = DISK_readsector(GPTSECTOR);
269			if (secbuf == NULL)
270			return;
271
272			memcpy(&sig, secbuf, sizeof(sig));
273			if (letoh64(sig) == GPTSIGNATURE) {
274			memset(secbuf, 0, sizeof(sig));
275			DISK_writesector(secbuf, GPTSECTOR);
276			}
277			free(secbuf);
278
279			secbuf = DISK_readsector(lastsec);
280			if (secbuf == NULL)
281			return;
282
283			memcpy(&sig, secbuf, sizeof(sig));
284			if (letoh64(sig) == GPTSIGNATURE) {
285			memset(secbuf, 0, sizeof(sig));
286			DISK_writesector(secbuf, lastsec);
287			}
288			free(secbuf);
289			}
290
291			/*
292			* Returns 0 if the MBR with the provided partition array is a GPT protective
293			* MBR, and returns 1 otherwise. A GPT protective MBR would have one and only
294			* one MBR partition, an EFI partition that either covers the whole disk or as
295			* much of it as is possible with a 32bit size field.
296			*
297			* Taken from kern/subr_disk.c.
298			*
299			* NOTE: MS always uses a size of UINT32_MAX for the EFI partition!**
300			*/
301			int
302			gpt_chk_mbr(struct dos_partition *dp, u_int64_t dsize)
303			{
304			struct dos_partition *dp2;
305			int efi, found, i;
306			u_int32_t psize;
307
308			found = efi = 0;
309			for (dp2=dp, i=0; i < NDOSPART; i++, dp2++) {
310			if (dp2->dp_typ == DOSPTYP_UNUSED)
311			continue;
312			found++;
313			if (dp2->dp_typ != DOSPTYP_EFI)
314			continue;
315			psize = letoh32(dp2->dp_size);
316			if (psize == (dsize - 1) \|\|
317			psize == UINT32_MAX) {
318			if (letoh32(dp2->dp_start) == 1)
319			efi++;
320			}
321			}
322			if (found == 1 && efi == 1)
323			return (0);
324
325			return (1);
326			}
327