Add GPT editing. Based on GSOC 2014 work by Markus Muller.

12 files changed, 759 insertions, 165 deletions

diff --git a/sbin/fdisk/cmd.c b/sbin/fdisk/cmd.c
index 19b5e2f9606..6d445017f49 100644
--- a/sbin/fdisk/cmd.c
+++ b/sbin/fdisk/cmd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cmd.c,v 1.82 2015/04/02 18:00:55 krw Exp $	*/
+/*	$OpenBSD: cmd.c,v 1.83 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -16,6 +16,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <sys/param.h>
 #include <sys/types.h>
 #include <sys/fcntl.h>
 #include <sys/disklabel.h>
@@ -26,30 +27,53 @@
 #include <stdlib.h>
 #include <signal.h>
 #include <unistd.h>
+#include <uuid.h>
 
 #include "disk.h"
 #include "misc.h"
 #include "part.h"
 #include "mbr.h"
+#include "gpt.h"
 #include "user.h"
 #include "cmd.h"
 
 int reinited;
 
+/* Some helper functions for GPT handling. */
+int Xgedit(char *);
+int Xgsetpid(char *);
+
 int
 Xreinit(char *args, struct mbr *mbr)
 {
 	struct dos_mbr dos_mbr;
+	int dogpt;
+
+	if (strncasecmp(args, "gpt", 3) == 0)
+		dogpt = 1;
+	else if (strncasecmp(args, "mbr", 3) == 0)
+		dogpt = 0;
+	else if (strlen(args) > 0) {
+		printf("Unrecognized modifier '%s'\n", args);
+		return (CMD_CONT);
+	} else if (MBR_protective_mbr(&initial_mbr) == 0)
+		dogpt = 1;
+	else
+		dogpt = 0;
 
 	MBR_make(&initial_mbr, &dos_mbr);
 	MBR_parse(&dos_mbr, mbr->offset, mbr->reloffset, mbr);
 
-	MBR_init(mbr);
+	if (dogpt) {
+		MBR_init_GPT(mbr);
+		GPT_init();
+		GPT_print("s");
+	} else {
+		MBR_init(mbr);
+		MBR_print(mbr, "s");
+	}
 	reinited = 1;
 
-	/* Tell em we did something */
-	printf("In memory copy is initialized to:\n");
-	MBR_print(mbr, args);
 	printf("Use 'write' to update disk.\n");
 
 	return (CMD_DIRTY);
@@ -91,8 +115,9 @@ Xswap(char *args, struct mbr *mbr)
 {
 	const char *errstr;
 	char *from, *to;
-	int pf, pt;
+	int pf, pt, maxpn;
 	struct prt pp;
+	struct gpt_partition gg;
 
 	to = args;
 	from = strsep(&to, " \t");
@@ -102,12 +127,17 @@ Xswap(char *args, struct mbr *mbr)
 		return (CMD_CONT);
 	}
 
-	pf = strtonum(from, 0, 3, &errstr);
+	if (letoh64(gh.gh_sig) == GPTSIGNATURE)
+		maxpn = NGPTPARTITIONS - 1;
+	else
+		maxpn = NDOSPART - 1;
+
+	pf = strtonum(from, 0, maxpn, &errstr);
 	if (errstr) {
 		printf("partition number is %s: %s\n", errstr, from);
 		return (CMD_CONT);
 	}
-	pt = strtonum(to, 0, 3, &errstr);
+	pt = strtonum(to, 0, maxpn, &errstr);
 	if (errstr) {
 		printf("partition number is %s: %s\n", errstr, to);
 		return (CMD_CONT);
@@ -118,20 +148,71 @@ Xswap(char *args, struct mbr *mbr)
 		return (CMD_CONT);
 	}
 
-	pp = mbr->part[pt];
-	mbr->part[pt] = mbr->part[pf];
-	mbr->part[pf] = pp;
+	if (letoh64(gh.gh_sig) == GPTSIGNATURE) {
+		gg = gp[pt];
+		gp[pt] = gp[pf];
+		gp[pf] = gg;
+	} else {
+		pp = mbr->part[pt];
+		mbr->part[pt] = mbr->part[pf];
+		mbr->part[pf] = pp;
+	}
 
 	return (CMD_DIRTY);
 }
 
 int
+Xgedit(char *args)
+{
+	const char *errstr;
+	struct gpt_partition *gg;
+	char *name;
+	u_int64_t bs, ns;
+	int pn, ret;
+
+	pn = strtonum(args, 0, NGPTPARTITIONS - 1, &errstr);
+	if (errstr) {
+		printf("partition number is %s: %s\n", errstr, args);
+		return (CMD_CONT);
+	}
+	gg = &gp[pn];
+
+	/* Edit partition type */
+	ret = Xgsetpid(args);
+
+	/* Unused, so just zero out */
+	if (uuid_is_nil(&gg->gp_type, NULL)) {
+		memset(gg, 0, sizeof(struct gpt_partition));
+		printf("Partition %d is disabled.\n", pn);
+		return (ret);
+	}
+
+	/* Change table entry */
+	bs = getuint64("Partition offset", letoh64(gh.gh_lba_start),
+	    letoh64(gh.gh_lba_end));
+	ns = getuint64("Partition size", letoh64(gh.gh_lba_end) - bs + 1,
+	    letoh64(gh.gh_lba_end) - bs + 1);
+
+	gg->gp_lba_start = htole64(bs);
+	gg->gp_lba_end = htole64(bs + ns - 1);
+
+	/* Ask for partition name. */
+	name = ask_string("partition name", utf16le_to_string(gg->gp_name));
+	memcpy(gg->gp_name, string_to_utf16le(name), sizeof(gg->gp_name));
+
+	return (ret);
+}
+
+int
 Xedit(char *args, struct mbr *mbr)
 {
 	const char *errstr;
 	int pn, num, ret;
 	struct prt *pp;
 
+	if (letoh64(gh.gh_sig) == GPTSIGNATURE)
+		return (Xgedit(args));
+
 	pn = strtonum(args, 0, 3, &errstr);
 	if (errstr) {
 		printf("partition number is %s: %s\n", errstr, args);
@@ -187,12 +268,52 @@ Xedit(char *args, struct mbr *mbr)
 }
 
 int
+Xgsetpid(char *args)
+{
+	const char *errstr;
+	struct uuid guid;
+	struct gpt_partition *gg;
+	int pn, num, status;
+
+	pn = strtonum(args, 0, NGPTPARTITIONS - 1, &errstr);
+	if (errstr) {
+		printf("partition number is %s: %s\n", errstr, args);
+		return (CMD_CONT);
+	}
+	gg = &gp[pn];
+
+	/* Print out current table entry */
+	GPT_print_parthdr();
+	GPT_print_part(pn, "s");
+
+	/* Ask for partition type or GUID. */
+	num = ask_pid(0, &guid);
+	if (num <= 0xff)
+		guid = *(PRT_type_to_uuid(num));
+	uuid_enc_le(&gg->gp_type, &guid);
+
+	if (uuid_is_nil(&gg->gp_guid, NULL)) {
+		uuid_create(&guid, &status);
+		if (status != uuid_s_ok) {
+			printf("could not create guid for partition\n");
+			return (CMD_CONT);
+		}
+		uuid_enc_le(&gg->gp_guid, &guid);
+	}
+
+	return (CMD_DIRTY);
+}
+
+int
 Xsetpid(char *args, struct mbr *mbr)
 {
 	const char *errstr;
 	int pn, num;
 	struct prt *pp;
 
+	if (letoh64(gh.gh_sig) == GPTSIGNATURE)
+		return (Xgsetpid(args));
+
 	pn = strtonum(args, 0, 3, &errstr);
 	if (errstr) {
 		printf("partition number is %s: %s\n", errstr, args);
@@ -205,7 +326,7 @@ Xsetpid(char *args, struct mbr *mbr)
 	PRT_print(pn, pp, NULL);
 
 	/* Ask for MBR partition type */
-	num = ask_pid(pp->id, 0x01, 0xff);
+	num = ask_pid(pp->id, NULL);
 	if (num == pp->id)
 		return (CMD_CONT);
 
@@ -258,8 +379,10 @@ int
 Xprint(char *args, struct mbr *mbr)
 {
 
-	DISK_printgeometry(args);
-	MBR_print(mbr, args);
+	if (MBR_protective_mbr(mbr) == 0 && letoh64(gh.gh_sig) == GPTSIGNATURE)
+		GPT_print(args);
+	else
+		MBR_print(mbr, args);
 
 	return (CMD_CONT);
 }
@@ -291,9 +414,19 @@ Xwrite(char *args, struct mbr *mbr)
 		return (CMD_CONT);
 	}
 
-	/* Make sure GPT doesn't get in the way. */
-	if (reinited)
+	if (letoh64(gh.gh_sig) == GPTSIGNATURE) {
+		printf("Writing GPT.\n");
+		if (GPT_write(fd) == -1) {
+			int saved_errno = errno;
+			warn("error writing GPT");
+			close(fd);
+			errno = saved_errno;
+			return (CMD_CONT);
+		}
+	} else if (reinited) {
+		/* Make sure GPT doesn't get in the way. */
 		MBR_zapgpt(fd, &dos_mbr, DL_GETDSIZE(&dl) - 1);
+	}
 
 	/* Refresh in memory copy to reflect what was just written. */
 	MBR_parse(&dos_mbr, mbr->offset, mbr->reloffset, mbr);
@@ -324,10 +457,26 @@ Xexit(char *args, struct mbr *mbr)
 int
 Xhelp(char *args, struct mbr *mbr)
 {
+	char *mbrstr, *gpthelp;
 	int i;
 
-	for (i = 0; cmd_table[i].cmd != NULL; i++)
+	for (i = 0; cmd_table[i].cmd != NULL; i++) {
+		if (letoh64(gh.gh_sig) == GPTSIGNATURE) {
+			if (cmd_table[i].gpt == 0)
+				continue;
+			gpthelp = strdup(cmd_table[i].help);
+			mbrstr = strstr(gpthelp, "MBR");
+			if (mbrstr) {
+				memcpy(mbrstr, "GPT", 3);
+				printf("\t%s\t\t%s\n", cmd_table[i].cmd,
+				    gpthelp);
+				free(gpthelp);
+				continue;
+			}
+		}
 		printf("\t%s\t\t%s\n", cmd_table[i].cmd, cmd_table[i].help);
+	}
+
 	return (CMD_CONT);
 }
 
@@ -345,38 +494,57 @@ int
 Xflag(char *args, struct mbr *mbr)
 {
 	const char *errstr;
-	int i, pn = -1, val = -1;
+	int i, maxpn, pn = -1;
+	long long val = -1;
 	char *part, *flag;
 
 	flag = args;
 	part = strsep(&flag, " \t");
 
-	pn = strtonum(part, 0, 3, &errstr);
+	if (letoh64(gh.gh_sig) == GPTSIGNATURE)
+		maxpn = NGPTPARTITIONS - 1;
+	else
+		maxpn = NDOSPART - 1;
+
+	pn = strtonum(part, 0, maxpn, &errstr);
 	if (errstr) {
 		printf("partition number is %s: %s.\n", errstr, part);
 		return (CMD_CONT);
 	}
 
 	if (flag != NULL) {
-		val = (int)strtonum(flag, 0, 0xff, &errstr);
+		/* Set flag to value provided. */
+		if (letoh64(gh.gh_sig) == GPTSIGNATURE)
+			val = strtonum(flag, 0, LLONG_MAX, &errstr);
+		else
+			val = strtonum(flag, 0, 0xff, &errstr);
 		if (errstr) {
 			printf("flag value is %s: %s.\n", errstr, flag);
 			return (CMD_CONT);
 		}
-	}
-
-	if (val == -1) {
+		if (letoh64(gh.gh_sig) == GPTSIGNATURE)
+			gp[pn].gp_attrs = htole64(val);
+		else
+			mbr->part[pn].flag = val;
+		printf("Partition %d flag value set to 0x%llx.\n", pn, val);
+	} else {
 		/* Set active flag */
-		for (i = 0; i < 4; i++) {
-			if (i == pn)
-				mbr->part[i].flag = DOSACTIVE;
-			else
-				mbr->part[i].flag = 0x00;
+		if (letoh64(gh.gh_sig) == GPTSIGNATURE) {
+			for (i = 0; i < NGPTPARTITIONS; i++) {
+				if (i == pn)
+					gp[i].gp_attrs = htole64(GPTDOSACTIVE);
+				else
+					gp[i].gp_attrs = htole64(0);
+			}
+		} else {
+			for (i = 0; i < NDOSPART; i++) {
+				if (i == pn)
+					mbr->part[i].flag = DOSACTIVE;
+				else
+					mbr->part[i].flag = 0x00;
+			}
 		}
 		printf("Partition %d marked active.\n", pn);
-	} else {
-		mbr->part[pn].flag = val;
-		printf("Partition %d flag value set to 0x%x.\n", pn, val);
 	}
 
 	return (CMD_DIRTY);
diff --git a/sbin/fdisk/cmd.h b/sbin/fdisk/cmd.h
index 9d478b64668..af3e7675519 100644
--- a/sbin/fdisk/cmd.h
+++ b/sbin/fdisk/cmd.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cmd.h,v 1.17 2015/03/18 14:46:59 krw Exp $	*/
+/*	$OpenBSD: cmd.h,v 1.18 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -27,6 +27,7 @@
 
 struct cmd {
 	char *cmd;
+	int  gpt;
 	int (*fcn)(char *, struct mbr *);
 	char *help;
 };
diff --git a/sbin/fdisk/fdisk.c b/sbin/fdisk/fdisk.c
index f1605c2f94c..450d41edd19 100644
--- a/sbin/fdisk/fdisk.c
+++ b/sbin/fdisk/fdisk.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: fdisk.c,v 1.78 2015/10/05 01:39:08 krw Exp $	*/
+/*	$OpenBSD: fdisk.c,v 1.79 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -71,8 +71,8 @@ int
 main(int argc, char *argv[])
 {
 	ssize_t len;
-	int ch, fd;
-	int i_flag = 0, e_flag = 0, u_flag = 0;
+	int ch, fd, error;
+	int i_flag = 0, e_flag = 0, f_flag = 0, u_flag = 0;
 	int c_arg = 0, h_arg = 0, s_arg = 0;
 	u_int32_t l_arg = 0;
 	char *query;
@@ -97,6 +97,7 @@ main(int argc, char *argv[])
 			e_flag = 1;
 			break;
 		case 'f':
+			f_flag = 1;
 			mbrfile = optarg;
 			break;
 		case 'c':
@@ -148,18 +149,24 @@ main(int argc, char *argv[])
 	else
 		disk.name = argv[0];
 
-	if (g_flag != 0 && i_flag == 0) {
-		warnx("-g specified without -i");
-		usage();
-	}
+	/* Start with the disklabel geometry and get the sector size. */
+	DISK_getlabelgeometry();
 
 	if (b_arg > 0 && i_flag == 0) {
 		warnx("-b specified without -i");
 		usage();
 	}
 
-	/* Start with the disklabel geometry and get the sector size. */
-	DISK_getlabelgeometry();
+	if (g_flag != 0 && i_flag == 0) {
+		warnx("-g specified without -i");
+		usage();
+	}
+
+	/* Get the GPT if present. */
+	if (GPT_get_gpt()) {
+		memset(&gh, 0, sizeof(gh));
+		memset(&gp, 0, sizeof(gp));
+	}
 
 	if (c_arg | h_arg | s_arg) {
 		/* Use supplied geometry if it is completely specified. */
@@ -188,13 +195,25 @@ main(int argc, char *argv[])
 		USER_print_disk();
 
 	/* Create initial/default MBR. */
+	if (i_flag == 0) {
+		fd = DISK_open(disk.name, O_RDONLY);
+		error = MBR_read(fd, 0, &dos_mbr);
+		close(fd);
+		if (error)
+			errx(1, "Can't read sector 0!");
+		MBR_parse(&dos_mbr, 0, 0, &initial_mbr);
+	}
+
 	if (mbrfile != NULL && (fd = open(mbrfile, O_RDONLY)) == -1) {
 		warn("%s", mbrfile);
 		warnx("using builtin MBR");
+		memset(&initial_mbr, 0, sizeof(initial_mbr));
 		mbrfile = NULL;
 	}
 	if (mbrfile == NULL) {
-		memcpy(&dos_mbr, builtin_mbr, sizeof(dos_mbr));
+		if (MBR_protective_mbr(&initial_mbr) != 0) {
+			memcpy(&dos_mbr, builtin_mbr, sizeof(dos_mbr));
+		}
 	} else {
 		len = read(fd, &dos_mbr, sizeof(dos_mbr));
 		if (len == -1)
@@ -204,7 +223,10 @@ main(int argc, char *argv[])
 			    mbrfile);
 		close(fd);
 	}
-	MBR_parse(&dos_mbr, 0, 0, &initial_mbr);
+	if (f_flag || MBR_protective_mbr(&initial_mbr) != 0)  {
+		memset(&gh, 0, sizeof(struct gpt_header));
+		MBR_parse(&dos_mbr, 0, 0, &initial_mbr);
+	}
 
 	query = NULL;
 	if (i_flag) {
@@ -221,15 +243,8 @@ main(int argc, char *argv[])
 		MBR_pcopy(&initial_mbr);
 		query = "Do you wish to write new MBR?";
 	}
-	if (query && ask_yn(query)) {
+	if (query && ask_yn(query))
 		Xwrite(NULL, &initial_mbr);
-		if (g_flag) {
-			fd = DISK_open(disk.name, O_RDWR);
-			if (GPT_write(fd) == -1)
-				warn("error writing GPT");
-			close(fd);
-		}
-	}
 
 	if (e_flag)
 		USER_edit(0, 0);
diff --git a/sbin/fdisk/gpt.c b/sbin/fdisk/gpt.c
index 698f8872980..7f37628c16f 100644
--- a/sbin/fdisk/gpt.c
+++ b/sbin/fdisk/gpt.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: gpt.c,v 1.1 2015/10/05 01:39:08 krw Exp $	*/
+/*	$OpenBSD: gpt.c,v 1.2 2015/10/26 15:08:26 krw Exp $	*/
 /*
  * Copyright (c) 2015 Markus Muller <mmu@grummel.net>
  * Copyright (c) 2015 Kenneth R Westerback <krw@openbsd.org>
@@ -16,10 +16,14 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+#include <sys/types.h>
 #include <sys/param.h>
 #include <sys/disklabel.h>
 #include <sys/dkio.h>
+#include <sys/fcntl.h>
 #include <sys/ioctl.h>
+#include <stdint.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
@@ -31,10 +35,274 @@
 #include "part.h"
 #include "gpt.h"
 
+#ifdef DEBUG
+#define DPRINTF(x...)	printf(x)
+#else
+#define DPRINTF(x...)
+#endif
+
 struct gpt_header gh;
 struct gpt_partition gp[NGPTPARTITIONS];
 
 int
+GPT_get_header(int fd, off_t where)
+{
+	char *secbuf;
+	uint64_t partlastlba;
+	int partspersec;
+	uint32_t orig_gh_csum, new_gh_csum;
+
+	secbuf = DISK_readsector(fd, where);
+	if (secbuf == 0)
+		return (1);
+
+	memcpy(&gh, secbuf, sizeof(struct gpt_header));
+	free(secbuf);
+
+	if (letoh64(gh.gh_sig) != GPTSIGNATURE) {
+		DPRINTF("gpt signature: expected 0x%llx, got 0x%llx\n",
+		    GPTSIGNATURE, letoh64(gh.gh_sig));
+		return (1);
+	}
+
+	if (letoh32(gh.gh_rev) != GPTREVISION) {
+		DPRINTF("gpt revision: expected 0x%x, got 0x%x\n",
+		    GPTREVISION, letoh32(gh.gh_rev));
+		return (1);
+	}
+
+	if (letoh64(gh.gh_lba_self) != where) {
+		DPRINTF("gpt self lba: expected %lld, got %llu\n",
+		    (long long)where, letoh64(gh.gh_lba_self));
+		return (1);
+	}
+
+	if (letoh32(gh.gh_size) != GPTMINHDRSIZE) {
+		DPRINTF("gpt header size: expected %u, got %u\n",
+		    GPTMINHDRSIZE, letoh32(gh.gh_size));
+		return (1);
+	}
+
+	if (letoh32(gh.gh_part_size) != GPTMINPARTSIZE) {
+		DPRINTF("gpt partition size: expected %u, got %u\n",
+		    GPTMINPARTSIZE, letoh32(gh.gh_part_size));
+		return (1);
+	}
+
+	if (letoh32(gh.gh_part_num) > NGPTPARTITIONS) {
+		DPRINTF("gpt partition count: expected <= %u, got %u\n",
+		    NGPTPARTITIONS, letoh32(gh.gh_part_num));
+		return (1);
+	}
+
+	orig_gh_csum = gh.gh_csum;
+	gh.gh_csum = 0;
+	new_gh_csum = crc32((unsigned char *)&gh, letoh32(gh.gh_size));
+	gh.gh_csum = orig_gh_csum;
+	if (letoh32(orig_gh_csum) != new_gh_csum) {
+		DPRINTF("gpt header checksum: expected 0x%x, got 0x%x\n",
+		    orig_gh_csum, new_gh_csum);
+		return (1);
+	}
+
+	if (letoh64(gh.gh_lba_end) >= DL_GETDSIZE(&dl)) {
+		DPRINTF("gpt last usable LBA: expected < %lld, got %llu\n",
+		    DL_GETDSIZE(&dl), letoh64(gh.gh_lba_end));
+		return (1);
+	}
+
+	if (letoh64(gh.gh_lba_start) >= letoh64(gh.gh_lba_end)) {
+		DPRINTF("gpt first usable LBA: expected < %llu, got %llu\n",
+		    letoh64(gh.gh_lba_start), letoh64(gh.gh_lba_start));
+		return (1);
+	}
+
+	if (letoh64(gh.gh_part_lba) <= letoh64(gh.gh_lba_end) &&
+	    letoh64(gh.gh_part_lba) >= letoh64(gh.gh_lba_start)) {
+		DPRINTF("gpt partition table start lba: expected < %llu or "
+		    "> %llu, got %llu\n", letoh64(gh.gh_lba_start),
+		    letoh64(gh.gh_lba_end), letoh64(gh.gh_part_lba));
+		return (1);
+	}
+
+	partspersec = dl.d_secsize / letoh32(gh.gh_part_size);
+	partlastlba = letoh64(gh.gh_part_lba) +
+	    ((letoh32(gh.gh_part_num) + partspersec - 1) / partspersec) - 1;
+	if (partlastlba <= letoh64(gh.gh_lba_end) &&
+	    partlastlba >= letoh64(gh.gh_lba_start)) {
+		DPRINTF("gpt partition table last LBA: expected < %llu or "
+		    "> %llu, got %llu\n", letoh64(gh.gh_lba_start),
+		    letoh64(gh.gh_lba_end), partlastlba);
+		return (1);
+	}
+
+	/*
+	 * Other possible paranoia checks:
+	 *	1) partition table starts before primary gpt lba.
+	 *	2) partition table extends into lowest partition.
+	 *	3) alt partition table starts before gh_lba_end.
+	 */
+	return (0);
+}
+
+int
+GPT_get_partition_table(int fd, off_t where)
+{
+	ssize_t len;
+	off_t off;
+	int secs;
+	uint32_t checksum, partspersec;
+
+	DPRINTF("gpt partition table being read from LBA %llu\n",
+	    letoh64(gh.gh_part_lba));
+
+	partspersec = dl.d_secsize / letoh32(gh.gh_part_size);
+	if (partspersec * letoh32(gh.gh_part_size) != dl.d_secsize) {
+		DPRINTF("gpt partition table entry invalid size. %u\n",
+		    letoh32(gh.gh_part_size));
+		return (1);
+	}
+	secs = (letoh32(gh.gh_part_num) + partspersec - 1) / partspersec;
+
+	memset(&gp, 0, sizeof(gp));
+
+	where *= dl.d_secsize;
+	off = lseek(fd, where, SEEK_SET);
+	if (off == -1) {
+		DPRINTF("seek to gpt partition table @ sector %llu failed\n",
+		    (unsigned long long)where / dl.d_secsize);
+		return (1);
+	}
+	len = read(fd, &gp, secs * dl.d_secsize);
+	if (len == -1 || len != secs * dl.d_secsize) {
+		DPRINTF("gpt partition table read failed.\n");
+		return (1);
+	}
+
+	checksum = crc32((unsigned char *)&gp, letoh32(gh.gh_part_num) *
+	    letoh32(gh.gh_part_size));
+	if (checksum != letoh32(gh.gh_part_csum)) {
+		DPRINTF("gpt partition table checksum: expected %x, got %x\n",
+		    checksum, letoh32(gh.gh_part_csum));
+		return (1);
+	}
+
+	return (0);
+}
+
+int
+GPT_get_gpt(void)
+{
+	int fd, privalid, altvalid;
+
+	fd = DISK_open(disk.name, O_RDONLY);
+
+	/*
+	 * primary header && primary partition table ||
+	 * alt header && alt partition table
+	 */
+	privalid = GPT_get_header(fd, GPTSECTOR);
+	if (privalid == 0)
+		privalid = GPT_get_partition_table(fd, gh.gh_part_lba);
+	if (privalid == 0) {
+		close(fd);
+		return (0);
+	}
+
+	altvalid = GPT_get_header(fd, DL_GETDSIZE(&dl) - 1);
+	if (altvalid == 0)
+		altvalid = GPT_get_partition_table(fd, gh.gh_part_lba);
+	if (altvalid == 0) {
+		close(fd);
+		return (0);
+	}
+
+	close(fd);
+
+	return (1);
+}
+
+void
+GPT_print(char *units)
+{
+	const int secsize = unit_types[SECTORS].conversion;
+	struct uuid guid;
+	char *guidstr = NULL;
+	double size;
+	int i, u, status;
+
+	printf("Disk: %s ", disk.name);
+
+	uuid_dec_le(&gh.gh_guid, &guid);
+	uuid_to_string(&guid, &guidstr, &status);
+	if (status == uuid_s_ok)
+		printf("%s ", guidstr);
+	else
+		printf("<invalid header guid> ");
+	free(guidstr);
+
+	u = unit_lookup(units);
+	size = ((double)disk.size * secsize) / unit_types[u].conversion;
+	printf("[%.0f ", size);
+	if (u == SECTORS && secsize != DEV_BSIZE)
+		printf("%d-byte ", secsize);
+	printf("%s]\n", unit_types[u].lname);
+
+	GPT_print_parthdr();
+
+	for (i = 0; i < letoh32(gh.gh_part_num); i++) {
+		if (uuid_is_nil(&gp[i].gp_type, NULL))
+			continue;
+		GPT_print_part(i, units);
+	}
+}
+
+void
+GPT_print_parthdr()
+{
+	printf("      First usable LBA: %llu  Last usable LBA: %llu\n",
+	    letoh64(gh.gh_lba_start), letoh64(gh.gh_lba_end));
+
+	printf("   #: uuid                                         "
+	    "lba         size \n");
+	printf("      type                                 name\n");
+	printf("----------------------------------------------------"
+	    "-----------------\n");
+}
+
+void
+GPT_print_part(int n, char *units)
+{
+	struct uuid guid;
+	const int secsize = unit_types[SECTORS].conversion;
+	struct gpt_partition *partn = &gp[n];
+	char *guidstr = NULL;
+	double size;
+	int u, status;
+
+	printf("%c%3d: ", (letoh64(partn->gp_attrs) & GPTDOSACTIVE)?'*':' ', n);
+
+	uuid_dec_le(&partn->gp_guid, &guid);
+	uuid_to_string(&guid, &guidstr, &status);
+	if (status != uuid_s_ok)
+		printf("<invalid partition guid>             ");
+	else
+		printf("%36s ", guidstr);
+	free(guidstr);
+
+	printf("%12lld ", letoh64(partn->gp_lba_start));
+
+	u = unit_lookup(units);
+	size = letoh64(partn->gp_lba_end) - letoh64(partn->gp_lba_start) + 1;
+	size = (size * secsize) / unit_types[u].conversion;
+	printf("%12.0f%s\n", size, unit_types[u].abbr);
+
+	uuid_dec_le(&partn->gp_type, &guid);
+	printf("      %-36s %-36s\n", PRT_uuid_to_type(&guid),
+	    utf16le_to_string(partn->gp_name));
+}
+
+int
 GPT_init(void)
 {
 	extern u_int32_t b_arg;
@@ -83,6 +351,8 @@ GPT_init(void)
 		uuid_enc_le(&gp[1].gp_guid, &guid);
 		gp[1].gp_lba_start = gh.gh_lba_start;
 		gp[1].gp_lba_end = htole64(letoh64(gh.gh_lba_start)+b_arg - 1);
+		memcpy(gp[1].gp_name, string_to_utf16le("EFI System Area"),
+		    sizeof(gp[1].gp_name));
 	}
 #endif
 	uuid_dec_be(gpt_uuid_openbsd, &guid);
@@ -103,6 +373,9 @@ GPT_init(void)
 	}
 #endif
 	gp[3].gp_lba_end = gh.gh_lba_end;
+	memcpy(gp[3].gp_name, string_to_utf16le("OpenBSD Area"),
+	    sizeof(gp[3].gp_name));
+
 	gh.gh_part_csum = crc32((unsigned char *)&gp, sizeof(gp));
 	gh.gh_csum = crc32((unsigned char *)&gh, sizeof(gh));
 
diff --git a/sbin/fdisk/gpt.h b/sbin/fdisk/gpt.h
index 2d4607c3667..1caca02305b 100644
--- a/sbin/fdisk/gpt.h
+++ b/sbin/fdisk/gpt.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: gpt.h,v 1.1 2015/10/05 01:39:08 krw Exp $	*/
+/*	$OpenBSD: gpt.h,v 1.2 2015/10/26 15:08:26 krw Exp $	*/
 /*
  * Copyright (c) 2015 Markus Muller <mmu@grummel.net>
  * Copyright (c) 2015 Kenneth R Westerback <krw@openbsd.org>
@@ -16,8 +16,15 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
 
+int GPT_get_hdr(int, off_t);
+int GPT_get_partition_table(int, off_t);
+int GPT_get_gpt(void);
 int GPT_init(void);
 int GPT_write(int);
 
+void GPT_print(char *);
+void GPT_print_part(int, char *);
+void GPT_print_parthdr(void);
+
 extern struct gpt_header gh;
 extern struct gpt_partition gp[NGPTPARTITIONS];
diff --git a/sbin/fdisk/mbr.c b/sbin/fdisk/mbr.c
index b9eb693a3d1..211ed3f5190 100644
--- a/sbin/fdisk/mbr.c
+++ b/sbin/fdisk/mbr.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mbr.c,v 1.55 2015/10/05 01:39:08 krw Exp $	*/
+/*	$OpenBSD: mbr.c,v 1.56 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -28,6 +28,7 @@
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <memory.h>
 
 #include "disk.h"
@@ -37,6 +38,33 @@
 
 struct mbr initial_mbr;
 
+int
+MBR_protective_mbr(struct mbr *mbr)
+{
+	u_int64_t dsize;
+	int efi, found, i;
+	u_int32_t psize;
+
+	found = efi = 0;
+	for (i = 0; i < NDOSPART; i++) {
+		if (mbr->part[i].id == DOSPTYP_UNUSED)
+			continue;
+		found++;
+		if (mbr->part[i].id != DOSPTYP_EFI)
+			continue;
+		dsize = DL_GETDSIZE(&dl);
+		psize = mbr->part[i].ns;
+		if (psize == (dsize - 1) || psize == UINT32_MAX) {
+			if (mbr->part[i].bs == 1)
+				efi++;
+		}
+	}
+	if (found == 1 && efi == 1)
+		return (0);
+
+	return (1);
+}
+
 void
 MBR_init_GPT(struct mbr *mbr)
 {
@@ -167,6 +195,8 @@ 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);
diff --git a/sbin/fdisk/mbr.h b/sbin/fdisk/mbr.h
index 294dea61114..0673f87fb45 100644
--- a/sbin/fdisk/mbr.h
+++ b/sbin/fdisk/mbr.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mbr.h,v 1.25 2015/10/05 01:39:08 krw Exp $	*/
+/*	$OpenBSD: mbr.h,v 1.26 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -39,5 +39,6 @@ int MBR_write(int, off_t, struct dos_mbr *);
 void MBR_pcopy(struct mbr *);
 void MBR_zapgpt(int, struct dos_mbr *, uint64_t);
 void MBR_init_GPT(struct mbr *);
+int MBR_protective_mbr(struct mbr *);
 
 #endif /* _MBR_H */
diff --git a/sbin/fdisk/misc.c b/sbin/fdisk/misc.c
index e6416147c7d..cc95a29875e 100644
--- a/sbin/fdisk/misc.c
+++ b/sbin/fdisk/misc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: misc.c,v 1.53 2015/10/07 00:04:57 krw Exp $	*/
+/*	$OpenBSD: misc.c,v 1.54 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -24,6 +24,7 @@
 #include <string.h>
 #include <err.h>
 #include <errno.h>
+#include <uuid.h>
 
 #include "disk.h"
 #include "misc.h"
@@ -60,18 +61,38 @@ unit_lookup(char *units)
 }
 
 int
+string_from_line(char *buf, size_t buflen)
+{
+	char *line;
+	size_t sz;
+
+	line = fgetln(stdin, &sz);
+	if (line == NULL)
+		return (1);
+
+	if (line[sz - 1] == '\n')
+		line[--sz] = '\0';
+
+	if (sz < buflen) {
+		memcpy(buf, line, sz);
+		buf[sz] = '\0';
+	} else {
+		memcpy(buf, line, buflen - 1);
+		buf[buflen - 1] = '\0';
+	}
+
+	return (0);
+}
+
+int
 ask_cmd(char **cmd, char **args)
 {
 	static char lbuf[100];
 	char *cp, *buf;
-	size_t lbuflen;
 
 	/* Get input */
-	if (fgets(lbuf, sizeof lbuf, stdin) == NULL)
+	if (string_from_line(lbuf, sizeof(lbuf)))
 		errx(1, "eof");
-	lbuflen = strlen(lbuf);
-	if (lbuflen > 0 && lbuf[lbuflen - 1] == '\n')
-		lbuf[lbuflen - 1] = '\0';
 
 	/* Parse input */
 	buf = lbuf;
@@ -89,7 +110,6 @@ ask_num(const char *str, int dflt, int low, int high)
 {
 	char lbuf[100];
 	const char *errstr;
-	size_t lbuflen;
 	int num;
 
 	if (dflt < low)
@@ -100,13 +120,9 @@ ask_num(const char *str, int dflt, int low, int high)
 	do {
 		printf("%s [%d - %d]: [%d] ", str, low, high, dflt);
 
-		if (fgets(lbuf, sizeof lbuf, stdin) == NULL)
+		if (string_from_line(lbuf, sizeof(lbuf)))
 			errx(1, "eof");
 
-		lbuflen = strlen(lbuf);
-		if (lbuflen > 0 && lbuf[lbuflen - 1] == '\n')
-			lbuf[lbuflen - 1] = '\0';
-
 		if (lbuf[0] == '\0') {
 			num = dflt;
 			errstr = NULL;
@@ -121,36 +137,29 @@ ask_num(const char *str, int dflt, int low, int high)
 }
 
 int
-ask_pid(int dflt, int low, int high)
+ask_pid(int dflt, struct uuid *guid)
 {
 	char lbuf[100], *cp;
-	size_t lbuflen;
-	int num = -1;
-
-	if (low == 1)
-		low = 0;	/* Show continguous range */
-
-	if (dflt < low)
-		dflt = low;
-	else if (dflt > high)
-		dflt = high;
+	int num = -1, status;
 
 	do {
-		printf("Partition id ('0' to disable) [%X - %X]: [%X] ", low,
-		    high, dflt);
+		printf("Partition id ('0' to disable) [01 - FF]: [%X] ", dflt);
 		printf("(? for help) ");
 
-		if (fgets(lbuf, sizeof lbuf, stdin) == NULL)
+		if (string_from_line(lbuf, sizeof(lbuf)))
 			errx(1, "eof");
-		lbuflen = strlen(lbuf);
-		if (lbuflen > 0 && lbuf[lbuflen - 1] == '\n')
-			lbuf[lbuflen - 1] = '\0';
 
 		if (lbuf[0] == '?') {
 			PRT_printall();
 			continue;
 		}
 
+		if (guid) {
+			uuid_from_string(lbuf, guid, &status);
+			if (status == uuid_s_ok)
+				return (0x100);
+		}
+
 		/* Convert */
 		cp = lbuf;
 		num = strtol(lbuf, &cp, 16);
@@ -160,13 +169,13 @@ ask_pid(int dflt, int low, int high)
 			num = dflt;
 		if (*cp != '\0') {
 			printf("'%s' is not a valid number.\n", lbuf);
-			num = low - 1;
+			num = -1;
 		} else if (num == 0) {
 			break;
-		} else if (num < low || num > high) {
+		} else if (num < 0 || num > 0xff) {
 			printf("'%x' is out of range.\n", num);
 		}
-	} while (num < low || num > high);
+	} while (num < 0 || num > 0xff);
 
 	return (num);
 }
@@ -215,13 +224,9 @@ getuint64(char *prompt, u_int64_t oval, u_int64_t maxval)
 	do {
 		printf("%s: [%llu] ", prompt, oval);
 
-		if (fgets(buf, sizeof(buf), stdin) == NULL)
+		if (string_from_line(buf, sizeof(buf)))
 			errx(1, "eof");
 
-		n = strlen(buf);
-		if (n > 0 && buf[n-1] == '\n')
-			buf[--n] = '\0';
-
 		if (buf[0] == '\0') {
 			return (oval);
 		} else if (buf[0] == '*' && buf[1] == '\0') {
@@ -229,6 +234,7 @@ getuint64(char *prompt, u_int64_t oval, u_int64_t maxval)
 		}
 
 		/* deal with units */
+		n = strlen(buf);
 		switch (tolower((unsigned char)buf[n-1])) {
 		case 'c':
 			unit = 'c';
@@ -318,28 +324,17 @@ getuint64(char *prompt, u_int64_t oval, u_int64_t maxval)
 char *
 ask_string(const char *prompt, const char *oval)
 {
-	static char buf[BUFSIZ];
-	int n;
+	static char buf[37];
 
 	buf[0] = '\0';
-	do {
-		printf("%s: [%s] ", prompt, oval ? oval : "");
-		if (fgets(buf, sizeof(buf), stdin) == NULL) {
-			buf[0] = '\0';
-			if (feof(stdin)) {
-				clearerr(stdin);
-				putchar('\n');
-				return(NULL);
-			}
-		}
-		n = strlen(buf);
-		if (n > 0 && buf[n-1] == '\n')
-			buf[--n] = '\0';
-		else if (oval != NULL && buf[0] == '\0')
-			strlcpy(buf, oval, sizeof(buf));
-	} while (buf[0] == '?');
+	printf("%s: [%s] ", prompt, oval ? oval : "");
+	if (string_from_line(buf, sizeof(buf)))
+		errx(1, "eof");
 
-	return(&buf[0]);
+	if (buf[0] == '\0' && oval)
+		strlcpy(buf, oval, sizeof(buf));
+
+	return(buf);
 }
 
 /*
@@ -372,3 +367,37 @@ crc32(const u_char *buf, const u_int32_t size)
 
 	return ~crc;
 }
+
+char *
+utf16le_to_string(u_int16_t *utf)
+{
+	static char name[36];
+	int i;
+
+	for (i = 0; i < sizeof(name); i++) {
+		name[i] = letoh16(utf[i]) & 0x7F;
+		if (name[i] == '\0')
+			break;
+	}
+	if (i == sizeof(name))
+		name[i - 1] = '\0';
+
+	return (name);
+}
+
+u_int16_t *
+string_to_utf16le(char *ch)
+{
+	static u_int16_t utf[36];
+	int i;
+
+	for (i = 0; i < sizeof(utf); i++) {
+		utf[i] = htole16((unsigned int)ch[i]);
+		if (utf[i] == 0)
+			break;
+	}
+	if (i == sizeof(utf))
+		utf[i - 1] = 0;
+
+	return (utf);
+}
diff --git a/sbin/fdisk/misc.h b/sbin/fdisk/misc.h
index 04d95c5865d..263fbd2d5c5 100644
--- a/sbin/fdisk/misc.h
+++ b/sbin/fdisk/misc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: misc.h,v 1.30 2015/03/30 17:11:49 krw Exp $	*/
+/*	$OpenBSD: misc.h,v 1.31 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -29,12 +29,15 @@ extern struct unit_type unit_types[];
 
 /* Prototypes */
 int unit_lookup(char *);
+int string_from_line(char *, size_t);
 int ask_cmd(char **, char **);
 int ask_num(const char *, int, int, int);
-int ask_pid(int, int, int);
+int ask_pid(int, struct uuid *);
 char *ask_string(const char *, const char *);
 int ask_yn(const char *);
 u_int64_t getuint64(char *, u_int64_t, u_int64_t);
 u_int32_t crc32(const u_char *, const u_int32_t);
+char *utf16le_to_string(u_int16_t *);
+u_int16_t *string_to_utf16le(char *);
 
 #endif /* _MISC_H */
diff --git a/sbin/fdisk/part.c b/sbin/fdisk/part.c
index 1ad2a85f5b9..04ce07a7d18 100644
--- a/sbin/fdisk/part.c
+++ b/sbin/fdisk/part.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: part.c,v 1.72 2015/03/27 16:06:00 krw Exp $	*/
+/*	$OpenBSD: part.c,v 1.73 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -20,7 +20,9 @@
 #include <sys/disklabel.h>
 #include <err.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
+#include <uuid.h>
 
 #include "disk.h"
 #include "misc.h"
@@ -31,39 +33,40 @@ int	PRT_check_chs(struct prt *partn);
 static const struct part_type {
 	int	type;
 	char	sname[14];
+	char	guid[37];
 } part_types[] = {
-	{ 0x00, "unused      "},   /* unused */
-	{ 0x01, "DOS FAT-12  "},   /* Primary DOS with 12 bit FAT */
+	{ 0x00, "unused      ", "00000000-0000-0000-0000-000000000000" },
+	{ 0x01, "DOS FAT-12  ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
 	{ 0x02, "XENIX /     "},   /* XENIX / filesystem */
 	{ 0x03, "XENIX /usr  "},   /* XENIX /usr filesystem */
-	{ 0x04, "DOS FAT-16  "},   /* Primary DOS with 16 bit FAT */
+	{ 0x04, "DOS FAT-16  ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
 	{ 0x05, "Extended DOS"},   /* Extended DOS */
-	{ 0x06, "DOS > 32MB  "},   /* Primary 'big' DOS (> 32MB) */
-	{ 0x07, "NTFS        "},   /* NTFS */
+	{ 0x06, "DOS > 32MB  ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
+	{ 0x07, "NTFS        ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
 	{ 0x08, "AIX fs      "},   /* AIX filesystem */
 	{ 0x09, "AIX/Coherent"},   /* AIX boot partition or Coherent */
 	{ 0x0A, "OS/2 Bootmgr"},   /* OS/2 Boot Manager or OPUS */
-	{ 0x0B, "Win95 FAT-32"},   /* Primary Win95 w/ 32-bit FAT */
-	{ 0x0C, "Win95 FAT32L"},   /* Primary Win95 w/ 32-bit FAT LBA-mapped */
-	{ 0x0E, "DOS FAT-16  "},   /* Primary DOS w/ 16-bit FAT, CHS-mapped */
+	{ 0x0B, "Win95 FAT-32", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
+	{ 0x0C, "Win95 FAT32L", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
+	{ 0x0E, "DOS FAT-16  ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
 	{ 0x0F, "Extended LBA"},   /* Extended DOS LBA-mapped */
 	{ 0x10, "OPUS        "},   /* OPUS */
-	{ 0x11, "OS/2 hidden "},   /* OS/2 BM: hidden DOS 12-bit FAT */
+	{ 0x11, "OS/2 hidden ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
 	{ 0x12, "Compaq Diag."},   /* Compaq Diagnostics */
-	{ 0x14, "OS/2 hidden "},   /* OS/2 BM: hidden DOS 16-bit FAT <32M or Novell DOS 7.0 bug */
-	{ 0x16, "OS/2 hidden "},   /* OS/2 BM: hidden DOS 16-bit FAT >=32M */
-	{ 0x17, "OS/2 hidden "},   /* OS/2 BM: hidden IFS */
+	{ 0x14, "OS/2 hidden ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
+	{ 0x16, "OS/2 hidden ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
+	{ 0x17, "OS/2 hidden ", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
 	{ 0x18, "AST swap    "},   /* AST Windows swapfile */
 	{ 0x19, "Willowtech  "},   /* Willowtech Photon coS */
-	{ 0x1C, "ThinkPad Rec"},   /* IBM ThinkPad recovery partition */
-	{ 0x20, "Willowsoft  "},   /* Willowsoft OFS1 */
+	{ 0x1C, "ThinkPad Rec", "ebd0a0a2-b9e5-4433-87c0-68b6b72699c7" },
 	{ 0x24, "NEC DOS     "},   /* NEC DOS */
-	{ 0x27, "Win Recovery"},   /* Windows hidden Recovery Partition */
+	{ 0x27, "Win Recovery", "de94bba4-06d1-4d40-a16a-bfd50179d6ac" },
+	{ 0x20, "Willowsoft  "},   /* Willowsoft OFS1 */
 	{ 0x38, "Theos       "},   /* Theos */
 	{ 0x39, "Plan 9      "},   /* Plan 9 */
 	{ 0x40, "VENIX 286   "},   /* VENIX 286 or LynxOS */
 	{ 0x41, "Lin/Minux DR"},   /* Linux/MINIX (sharing disk with DRDOS) or Personal RISC boot */
-	{ 0x42, "LinuxSwap DR"},   /* SFS or Linux swap (sharing disk with DRDOS) */
+	{ 0x42, "LinuxSwap DR", "af9b60a0-1431-4f62-bc68-3311714a69ad" },
 	{ 0x43, "Linux DR    "},   /* Linux native (sharing disk with DRDOS) */
 	{ 0x4D, "QNX 4.2 Pri "},   /* QNX 4.2 Primary */
 	{ 0x4E, "QNX 4.2 Sec "},   /* QNX 4.2 Secondary */
@@ -86,30 +89,31 @@ static const struct part_type {
 	{ 0x69, "Novell      "},   /* Novell */
 	{ 0x70, "DiskSecure  "},   /* DiskSecure Multi-Boot */
 	{ 0x75, "PCIX        "},   /* PCIX */
+	{ 0x7f, "ChromeKernel", "fe3a2a5d-4f32-41a7-b725-accc3285a309" },
 	{ 0x80, "Minix (old) "},   /* Minix 1.1 ... 1.4a */
 	{ 0x81, "Minix (new) "},   /* Minix 1.4b ... 1.5.10 */
-	{ 0x82, "Linux swap  "},   /* Linux swap */
-	{ 0x83, "Linux files*"},   /* Linux filesystem */
+	{ 0x82, "Linux swap  ", "0657fd6d-a4ab-43c4-84e5-0933c84b4f4f" },
+	{ 0x83, "Linux files*", "0fc63daf-8483-4772-8e79-3d69d8477de4" },
 	{ 0x84, "OS/2 hidden "},   /* OS/2 hidden C: drive */
 	{ 0x85, "Linux ext.  "},   /* Linux extended */
 	{ 0x86, "NT FAT VS   "},   /* NT FAT volume set */
 	{ 0x87, "NTFS VS     "},   /* NTFS volume set or HPFS mirrored */
-	{ 0x8E, "Linux LVM   "},   /* Linux LVM */
+	{ 0x8E, "Linux LVM   ", "e6d6d379-f507-44c2-a23c-238f2a3df928" },
 	{ 0x93, "Amoeba FS   "},   /* Amoeba filesystem */
 	{ 0x94, "Amoeba BBT  "},   /* Amoeba bad block table */
 	{ 0x99, "Mylex       "},   /* Mylex EISA SCSI */
 	{ 0x9F, "BSDI        "},   /* BSDI BSD/OS */
 	{ 0xA0, "NotebookSave"},   /* Phoenix NoteBIOS save-to-disk */
-	{ 0xA5, "FreeBSD     "},   /* FreeBSD */
-	{ 0xA6, "OpenBSD     "},   /* OpenBSD */
+	{ 0xA5, "FreeBSD     ", "516e7cb4-6ecf-11d6-8ff8-00022d09712b" },
+	{ 0xA6, "OpenBSD     ", "824cc7a0-36a8-11e3-890a-952519ad3f61" },
 	{ 0xA7, "NEXTSTEP    "},   /* NEXTSTEP */
-	{ 0xA8, "MacOS X     "},   /* MacOS X main partition */
-	{ 0xA9, "NetBSD      "},   /* NetBSD */
-	{ 0xAB, "MacOS X boot"},   /* MacOS X boot partition */
-	{ 0xAF, "MacOS X HFS+"},   /* MacOS X HFS+ partition */
+	{ 0xA8, "MacOS X     ", "55465300-0000-11aa-aa11-00306543ecac" },
+	{ 0xA9, "NetBSD      ", "516e7cb4-6ecf-11d6-8ff8-00022d09712b" },
+	{ 0xAB, "MacOS X boot", "426f6f74-0000-11aa-aa11-00306543ecac" },
+	{ 0xAF, "MacOS X HFS+", "48465300-0000-11aa-aa11-00306543ecac" },
 	{ 0xB7, "BSDI filesy*"},   /* BSDI BSD/386 filesystem */
 	{ 0xB8, "BSDI swap   "},   /* BSDI BSD/386 swap */
-	{ 0xBF, "Solaris     "},   /* Solaris */
+	{ 0xBF, "Solaris     ", "6a85cf4d-1dd2-11b2-99a6-080020736631" },
 	{ 0xC0, "CTOS        "},   /* CTOS */
 	{ 0xC1, "DRDOSs FAT12"},   /* DRDOS/sec (FAT-12) */
 	{ 0xC4, "DRDOSs < 32M"},   /* DRDOS/sec (FAT-16, < 32M) */
@@ -120,9 +124,9 @@ static const struct part_type {
 	{ 0xE1, "SpeedStor   "},   /* DOS access or SpeedStor 12-bit FAT extended partition */
 	{ 0xE3, "SpeedStor   "},   /* DOS R/O or SpeedStor or Storage Dimensions */
 	{ 0xE4, "SpeedStor   "},   /* SpeedStor 16-bit FAT extended partition < 1024 cyl. */
-	{ 0xEB, "BeOS/i386   "},   /* BeOS for Intel */
+	{ 0xEB, "BeOS/i386   ", "42465331-3ba3-10f1-802a-4861696b7521" },
 	{ 0xEE, "EFI GPT     "},   /* EFI Protective Partition */
-	{ 0xEF, "EFI Sys     "},   /* EFI System Partition */
+	{ 0xEF, "EFI Sys     ", "c12a7328-f81f-11d2-ba4b-00a0c93ec93b" },
 	{ 0xF1, "SpeedStor   "},   /* SpeedStor or Storage Dimensions */
 	{ 0xF2, "DOS 3.3+ Sec"},   /* DOS 3.3+ Secondary */
 	{ 0xF4, "SpeedStor   "},   /* SpeedStor >1024 cyl. or LANstep or IBM PS/2 IML */
@@ -268,6 +272,7 @@ PRT_make(struct prt *partn, off_t offset, off_t reloff,
 void
 PRT_print(int num, struct prt *partn, char *units)
 {
+	const int secsize = unit_types[SECTORS].conversion;
 	double size;
 	int i;
 
@@ -281,8 +286,7 @@ PRT_print(int num, struct prt *partn, char *units)
 		printf("---------------------------------------"
 		    "----------------------------------------\n");
 	} else {
-		size = ((double)partn->ns * unit_types[SECTORS].conversion) /
-		    unit_types[i].conversion;
+		size = ((double)partn->ns * secsize) / unit_types[i].conversion;
 		printf("%c%1d: %.2X %6u %3u %3u - %6u %3u %3u "
 		    "[%12llu:%12.0f%s] %s\n",
 		    (partn->flag == DOSACTIVE)?'*':' ',
@@ -369,3 +373,58 @@ PRT_fix_CHS(struct prt *part)
 	part->ehead = head;
 	part->esect = sect;
 }
+
+char *
+PRT_uuid_to_type(struct uuid *uuid)
+{
+	static char partition_type[37];	/* Room for a GUID if needed. */
+	char *uuidstr = NULL;
+	int i, entries, status;
+
+	memset(partition_type, 0, sizeof(partition_type));
+
+	uuid_to_string(uuid, &uuidstr, &status);
+	if (status != uuid_s_ok)
+		goto done;
+
+	entries = sizeof(part_types) / sizeof(struct part_type);
+
+	for (i = 0; i < entries; i++) {
+		if (memcmp(part_types[i].guid, uuidstr,
+		    sizeof(part_types[i].guid)) == 0)
+			break;
+	}
+
+	if (i < entries)
+		strlcpy(partition_type, part_types[i].sname,
+		    sizeof(partition_type));
+	else
+		strlcpy(partition_type, uuidstr, sizeof(partition_type));
+
+done:
+	free(uuidstr);
+
+	return (partition_type);
+}
+
+struct uuid *
+PRT_type_to_uuid(int type)
+{
+	static struct uuid guid;
+	int i, entries, status = uuid_s_ok;
+
+	memset(&guid, 0, sizeof(guid));
+
+	entries = sizeof(part_types) / sizeof(struct part_type);
+
+	for (i = 0; i < entries; i++) {
+		if (part_types[i].type == type)
+			break;
+	}
+	if (i < entries)
+		uuid_from_string(part_types[i].guid, &guid, &status);
+	if (i == entries || status != uuid_s_ok)
+		uuid_from_string(part_types[0].guid, &guid, &status);
+
+	return (&guid);
+}
diff --git a/sbin/fdisk/part.h b/sbin/fdisk/part.h
index 645c1c8c2df..c1b2299f0ed 100644
--- a/sbin/fdisk/part.h
+++ b/sbin/fdisk/part.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: part.h,v 1.19 2015/03/26 14:08:12 krw Exp $	*/
+/*	$OpenBSD: part.h,v 1.20 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -34,6 +34,8 @@ void PRT_parse(struct dos_partition *, off_t, off_t,
     struct prt *);
 void PRT_make(struct prt *, off_t, off_t, struct dos_partition *);
 void PRT_print(int, struct prt *, char *);
+char *PRT_uuid_to_type(struct uuid *);
+struct uuid *PRT_type_to_uuid(int);
 
 /* This does CHS -> bs/ns */
 void PRT_fix_BN(struct prt *, int);
diff --git a/sbin/fdisk/user.c b/sbin/fdisk/user.c
index 65d995e9b4e..40d40a73253 100644
--- a/sbin/fdisk/user.c
+++ b/sbin/fdisk/user.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: user.c,v 1.44 2015/04/02 18:00:55 krw Exp $	*/
+/*	$OpenBSD: user.c,v 1.45 2015/10/26 15:08:26 krw Exp $	*/
 
 /*
  * Copyright (c) 1997 Tobias Weingartner
@@ -30,25 +30,26 @@
 #include "misc.h"
 #include "cmd.h"
 #include "user.h"
+#include "gpt.h"
 
 /* Our command table */
 struct cmd cmd_table[] = {
-	{"help",   Xhelp,	"Command help list"},
-	{"manual", Xmanual,	"Show entire OpenBSD man page for fdisk"},
-	{"reinit", Xreinit,	"Re-initialize loaded MBR (to defaults)"},
-	{"setpid", Xsetpid,	"Set the identifier of a given table entry"},
-	{"disk",   Xdisk,	"Edit current drive stats"},
-	{"edit",   Xedit,	"Edit given table entry"},
-	{"flag",   Xflag,	"Flag given table entry as bootable"},
-	{"update", Xupdate,	"Update machine code in loaded MBR"},
-	{"select", Xselect,	"Select extended partition table entry MBR"},
-	{"swap",   Xswap,	"Swap two partition entries"},
-	{"print",  Xprint,	"Print loaded MBR partition table"},
-	{"write",  Xwrite,	"Write loaded MBR to disk"},
-	{"exit",   Xexit,	"Exit edit of current MBR, without saving changes"},
-	{"quit",   Xquit,	"Quit edit of current MBR, saving current changes"},
-	{"abort",  Xabort,	"Abort program without saving current changes"},
-	{NULL,     NULL,	NULL}
+	{"help",   1, Xhelp,   "Command help list"},
+	{"manual", 1, Xmanual, "Show entire OpenBSD man page for fdisk"},
+	{"reinit", 1, Xreinit, "Re-initialize loaded MBR (to defaults)"},
+	{"setpid", 1, Xsetpid, "Set the identifier of a given table entry"},
+	{"disk",   0, Xdisk,   "Edit current drive stats"},
+	{"edit",   1, Xedit,   "Edit given table entry"},
+	{"flag",   1, Xflag,   "Flag given table entry as bootable"},
+	{"update", 0, Xupdate, "Update machine code in loaded MBR"},
+	{"select", 0, Xselect, "Select extended partition table entry MBR"},
+	{"swap",   1, Xswap,   "Swap two partition entries"},
+	{"print",  1, Xprint,  "Print loaded MBR partition table"},
+	{"write",  1, Xwrite,  "Write loaded MBR to disk"},
+	{"exit",   1, Xexit,   "Exit edit of current MBR, without saving changes"},
+	{"quit",   1, Xquit,   "Quit edit of current MBR, saving current changes"},
+	{"abort",  1, Xabort,  "Abort program without saving current changes"},
+	{NULL,     0, NULL,    NULL}
 };
 
 
@@ -96,7 +97,8 @@ again:
 			i = 0;
 
 		/* Check for valid command */
-		if (cmd_table[i].cmd == NULL) {
+		if ((cmd_table[i].cmd == NULL) || (letoh64(gh.gh_sig) ==
+		    GPTSIGNATURE && cmd_table[i].gpt == 0)) {
 			printf("Invalid command '%s'.  Try 'help'.\n", cmd);
 			continue;
 		}
@@ -141,13 +143,17 @@ USER_print_disk(void)
 	fd = DISK_open(disk.name, O_RDONLY);
 	offset = firstoff = 0;
 
-	DISK_printgeometry(NULL);
-
 	do {
 		error = MBR_read(fd, offset, &dos_mbr);
 		if (error == -1)
 			break;
 		MBR_parse(&dos_mbr, offset, firstoff, &mbr);
+		if (offset == 0 && MBR_protective_mbr(&mbr) == 0) {
+			if (letoh64(gh.gh_sig) == GPTSIGNATURE) {
+				GPT_print("s");
+				break;
+			}
+		}
 
 		MBR_print(&mbr, NULL);