Add uuidgen(2) and uuidgen(1).

The uuidgen command, by means of the uuidgen syscall, generates one
or more Universally Unique Identifiers compatible with OSF/DCE 1.1
version 1 UUIDs.

From the Perforce logs (change 11995):

Round of cleanups:
o  Give uuidgen() the correct prototype in syscalls.master
o  Define struct uuid according to DCE 1.1 in sys/uuid.h
o  Use struct uuid instead of uuid_t. The latter is defined
   in sys/uuid.h but should not be used in kernel land.
o  Add snprintf_uuid(), printf_uuid() and sbuf_printf_uuid()
   to kern_uuid.c for use in the kernel (currently geom_gpt.c).
o  Rename the non-standard struct uuid in kern/kern_uuid.c
   to struct uuid_private and give it a slightly better definition
   for better byte-order handling. See below.
o  In sys/gpt.h, fix the broken uuid definitions to match the now
   compliant struct uuid definition. See below.
o  In usr.bin/uuidgen/uuidgen.c catch up with struct uuid change.

A note about byte-order:
        The standard failed to provide a non-conflicting and
unambiguous definition for the binary representation. My initial
implementation always wrote the timestamp as a 64-bit little-endian
(2s-complement) integral. The clock sequence was always written
as a 16-bit big-endian (2s-complement) integral. After a good
nights sleep and couple of Pan Galactic Gargle Blasters (not
necessarily in that order :-) I reread the spec and came to the
conclusion that the time fields are always written in the native
by order, provided the the low, mid and hi chopping still occurs.
The spec mentions that you "might need to swap bytes if you talk
to a machine that has a different byte-order". The clock sequence
is always written in big-endian order (as is the IEEE 802 address)
because its division is resulting in bytes, making the ordering
unambiguous.

17 files changed, 774 insertions, 8 deletions

diff --git a/bin/uuidgen/Makefile b/bin/uuidgen/Makefile
new file mode 100644
index 0000000..81459e2
--- /dev/null
+++ b/bin/uuidgen/Makefile
@@ -0,0 +1,6 @@
+# $FreeBSD$
+
+PROG=	uuidgen
+WARNS?=	4
+
+.include <bsd.prog.mk>
diff --git a/bin/uuidgen/uuidgen.1 b/bin/uuidgen/uuidgen.1
new file mode 100644
index 0000000..d61f848
--- /dev/null
+++ b/bin/uuidgen/uuidgen.1
@@ -0,0 +1,71 @@
+.\" Copyright (c) 2002 Marcel Moolenaar
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\"
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd May 23, 2002
+.Dt UUIDGEN 1
+.Os
+.Sh NAME
+.Nm uuidgen
+.Nd generate universally unique identifiers
+.Sh SYNOPSIS
+.Nm
+.Op Fl 1
+.Op Fl n Ar count
+.Sh DESCRIPTION
+The
+.Nm
+utility by default generates a single universally unique identifier (UUID),
+also known as a globally unique identifier (GUID). The UUID is written to
+stdout. The following options can be used to change the number of identifiers
+and the method used:
+.Bl -tag -width indent
+.It Fl 1
+This option only has effect if multiple identifiers are to be generated and
+instructs
+.Nm
+to not generate them in batch, but one at a time.
+.It Fl n
+This option controls the number of identifiers generated. By default, multiple
+identifiers are generated in batch.
+.El
+.Pp
+Batched generation yields a dense set of identifiers in such a way that there
+is no identifier that is larger than the smallest identifier in the set and
+smaller than the largest identifier in the set and that is not already in the
+set.
+.Pp
+When generating the identifiers one at a time, the identifiers will be close
+to each other, but operating system latency and processing time will be
+reflected in the distance between two successive identifiers.
+.Sh DIAGNOSTICS
+.Ex -std
+.Sh SEE ALSO
+.Xr uuidgen 2
+.Sh HISTORY
+The
+.Nm
+command first appeared in
+.Fx 5.0 .
diff --git a/bin/uuidgen/uuidgen.c b/bin/uuidgen/uuidgen.c
new file mode 100644
index 0000000..59fd446
--- /dev/null
+++ b/bin/uuidgen/uuidgen.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2002 Marcel Moolenaar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $Id$
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/endian.h>
+#include <sys/uuid.h>
+
+#include <err.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static void
+usage(void)
+{
+	(void)fprintf(stderr, "usage: uuidgen [-1] [-n count]\n");
+	exit(1);
+}
+
+static void
+uuid_print(uuid_t *uuid)
+{
+	printf("%08x-%04x-%04x-%02x%02x-", uuid->time_low, uuid->time_mid,
+	    uuid->time_hi_and_version, uuid->clock_seq_hi_and_reserved,
+	    uuid->clock_seq_low);
+	printf("%02x%02x%02x%02x%02x%02x\n", uuid->node[0], uuid->node[1],
+	    uuid->node[2], uuid->node[3], uuid->node[4], uuid->node[5]);
+}
+
+int
+main(int argc, char *argv[])
+{
+	uuid_t *store, *uuid;
+	char *p;
+	int ch, count, i, iterate;
+
+	count = -1;	/* no count yet */
+	iterate = 0;	/* not one at a time */
+	while ((ch = getopt(argc, argv, "1n:")) != -1)
+		switch (ch) {
+		case '1':
+			iterate = 1;
+			break;
+		case 'n':
+			if (count > 0)
+				usage();
+			count = strtol(optarg, &p, 10);
+			if (*p != 0 || count < 1)
+				usage();
+			break;
+		default:
+			usage();
+		}
+	argv += optind;
+	argc -= optind;
+
+	if (argc)
+		usage();
+
+	if (count == -1)
+		count = 1;
+
+	store = (uuid_t*)malloc(sizeof(uuid_t) * count);
+	if (store == NULL)
+		err(1, "malloc()");
+
+	if (!iterate) {
+		/* Get them all in a single batch */
+		if (uuidgen(store, count) != 0)
+			err(1, "uuidgen()");
+	} else {
+		uuid = store;
+		for (i = 0; i < count; i++) {
+			if (uuidgen(uuid++, 1) != 0)
+				err(1, "uuidgen()");
+		}
+	}
+
+	uuid = store;
+	while (count--)
+		uuid_print(uuid++);
+
+	free(store);
+	return (0);
+}
diff --git a/lib/libc/sys/Makefile.inc b/lib/libc/sys/Makefile.inc
index 5f78b60..5133fff 100644
--- a/lib/libc/sys/Makefile.inc
+++ b/lib/libc/sys/Makefile.inc
@@ -81,7 +81,7 @@ MAN+=	_exit.2 accept.2 access.2 acct.2 adjtime.2 \
 	sigstack.2 sigsuspend.2 socket.2 socketpair.2 stat.2 statfs.2 \
 	swapon.2 symlink.2 sync.2 sysarch.2 syscall.2 \
 	truncate.2 umask.2 undelete.2 \
-	unlink.2 utimes.2 vfork.2 wait.2 write.2
+	unlink.2 utimes.2 uuidgen.2 vfork.2 wait.2 write.2
 .if !defined(NO_P1003_1B)
 MAN+=	sched_get_priority_max.2 sched_setparam.2 \
 	sched_setscheduler.2 sched_yield.2
diff --git a/lib/libc/sys/uuidgen.2 b/lib/libc/sys/uuidgen.2
new file mode 100644
index 0000000..9d6a522
--- /dev/null
+++ b/lib/libc/sys/uuidgen.2
@@ -0,0 +1,83 @@
+.\" Copyright (c) 2002 Marcel Moolenaar
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\"
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd May 26, 2002
+.Dt UUIDGEN 2
+.Os
+.Sh NAME
+.Nm uuidgen
+.Nd generate universally unique identifiers
+.Sh LIBRARY
+.Lb libc
+.Sh SYNOPSIS
+.In sys/uuid.h
+.Ft int
+.Fn uuidgen "uuid_t *store" "int count"
+.Sh DESCRIPTION
+The
+.Nm
+system call generates
+.Fa count
+universally unique identifiers (UUIDs) and writes them to the buffer
+pointed to by
+.Fa store .
+The identifiers are generated according to the syntax and semantics of the
+DCE version 1 variant of universally unique identifiers. When no IEEE 802
+address is available for the node field a random multicast address is
+generated for each call.
+.Pp
+When multiple identifiers are requested, the
+.Nm
+system call will generate identifiers that are adjacent in time.
+.Pp
+Universally unique identifiers, also known as globally unique identifiers,
+are normally represented as:
+.Bd -literal -offset indent
+63d81915-7140-11d6-903d-00022d09712b
+.Ed
+.Sh RETURN VALUES
+.Rv -std
+.Sh ERRORS
+The
+.Nm
+system call can fail with:
+.Bl -tag -width Er
+.It Bq Er EFAULT
+The buffer pointed to by
+.Fa store
+could not be written to for any or all identifiers.
+.It Bq Er EINVAL
+The
+.Fa count
+parameter is less than 1 or larger than the hard upper limit of 2048.
+.El
+.Sh SEE ALSO
+.Xr uuidgen 1
+.Sh HISTORY
+The
+.Nm
+system call first appeared in
+.Fx 5.0 .
diff --git a/sys/conf/files b/sys/conf/files
index 7a67183..6e3e365 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -863,6 +863,7 @@ kern/kern_sysctl.c	standard
 kern/kern_tc.c		standard
 kern/kern_time.c	standard
 kern/kern_timeout.c	standard
+kern/kern_uuid.c	standard
 kern/kern_xxx.c		standard
 kern/link_elf.c		standard
 kern/md5c.c		standard
diff --git a/sys/kern/init_sysent.c b/sys/kern/init_sysent.c
index 567ce4b..2dc7bc3 100644
--- a/sys/kern/init_sysent.c
+++ b/sys/kern/init_sysent.c
@@ -3,7 +3,7 @@
  *
  * DO NOT EDIT-- this file is automatically generated.
  * $FreeBSD$
- * created from FreeBSD: src/sys/kern/syscalls.master,v 1.111 2002/05/05 23:37:44 mux Exp 
+ * created from FreeBSD: src/sys/kern/syscalls.master,v 1.112 2002/05/28 05:58:06 marcel Exp 
  */
 
 #include "opt_compat.h"
@@ -414,4 +414,5 @@ struct sysent sysent[] = {
 	{ 0, (sy_call_t *)nosys },			/* 389 = __mac_set_file */
 	{ AS(kenv_args), (sy_call_t *)kenv },		/* 390 = kenv */
 	{ AS(lchflags_args), (sy_call_t *)lchflags },	/* 391 = lchflags */
+	{ AS(uuidgen_args), (sy_call_t *)uuidgen },	/* 392 = uuidgen */
 };
diff --git a/sys/kern/kern_uuid.c b/sys/kern/kern_uuid.c
new file mode 100644
index 0000000..ba5faa5
--- /dev/null
+++ b/sys/kern/kern_uuid.c
@@ -0,0 +1,222 @@
+/*
+ * Copyright (c) 2002 Marcel Moolenaar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <sys/endian.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/sbuf.h>
+#include <sys/socket.h>
+#include <sys/sysproto.h>
+#include <sys/uuid.h>
+
+#include <net/if.h>
+#include <net/if_dl.h>
+#include <net/if_types.h>
+
+/*
+ * See also:
+ *	http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt
+ *	http://www.opengroup.org/onlinepubs/009629399/apdxa.htm
+ *
+ * Note that the generator state is itself an UUID, but the time and clock
+ * sequence fields are written in the native byte order.
+ */
+
+CTASSERT(sizeof(struct uuid) == 16);
+
+/* We use an alternative, more convenient representation in the generator. */
+struct uuid_private {
+	union {
+		uint64_t	ll;		/* internal. */
+		struct {
+			uint32_t	low;
+			uint16_t	mid;
+			uint16_t	hi;
+		} x;
+	} time;
+	uint16_t	seq;			/* Big-endian. */
+	uint16_t	node[UUID_NODE_LEN>>1];
+};
+
+CTASSERT(sizeof(struct uuid_private) == 16);
+
+static struct uuid_private uuid_last;
+
+static struct mtx uuid_mutex;
+MTX_SYSINIT(uuid_lock, &uuid_mutex, "UUID generator mutex lock", MTX_DEF);
+
+/*
+ * Return the first MAC address we encounter or, if none was found,
+ * construct a sufficiently random multicast address. We don't try
+ * to return the same MAC address as previously returned. We always
+ * generate a new multicast address if no MAC address exists in the
+ * system.
+ * It would be nice to know if 'ifnet' or any of its sub-structures
+ * has been changed in any way. If not, we could simply skip the
+ * scan and safely return the MAC address we returned before.
+ */
+static void
+uuid_node(uint16_t *node)
+{
+	struct ifnet *ifp;
+	struct ifaddr *ifa;
+	struct sockaddr_dl *sdl;
+	int i;
+
+	/* XXX: lock ifnet. */
+	TAILQ_FOREACH(ifp, &ifnet, if_link) {
+		/* Walk the address list */
+		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
+			sdl = (struct sockaddr_dl*)ifa->ifa_addr;
+			if (sdl != NULL && sdl->sdl_family == AF_LINK &&
+			    sdl->sdl_type == IFT_ETHER) {
+				/* Got a MAC address. */
+				bcopy(LLADDR(sdl), node, UUID_NODE_LEN);
+				/* XXX: unlock ifnet. */
+				return;
+			}
+		}
+	}
+	/* XXX: unlock ifnet. */
+
+	for (i = 0; i < (UUID_NODE_LEN>>1); i++)
+		node[i] = (uint16_t)arc4random();
+	*((uint8_t*)node) |= 0x80;
+}
+
+/*
+ * Get the current time as a 60 bit count of 100-nanosecond intervals
+ * since 00:00:00.00, October 15,1582. We apply a magic offset to convert
+ * the Unix time since 00:00:00.00, Januari 1, 1970 to the date of the
+ * Gregorian reform to the Christian calendar.
+ */
+static uint64_t
+uuid_time(void)
+{
+	struct bintime bt;
+	uint64_t time = 0x01B21DD213814000LL;
+
+	bintime(&bt);
+	time += (uint64_t)bt.sec * 10000000LL;
+	time += (10000000LL * (uint32_t)(bt.frac >> 32)) >> 32;
+	return (time & ((1LL << 60) - 1LL));
+}
+
+#ifndef _SYS_SYSPROTO_H_
+struct uuidgen_args {
+	struct uuid *store;
+	int	count;
+};
+#endif
+
+int uuidgen(struct thread *td, struct uuidgen_args *uap)
+{
+	struct uuid_private uuid;
+	uint64_t time;
+	int error;
+
+	/*
+	 * Limit the number of UUIDs that can be created at the same time
+	 * to some arbitrary number. This isn't really necessary, but I
+	 * like to have some sort of upper-bound that's less than 2G :-)
+	 * XXX needs to be tunable.
+	 */
+	if (uap->count < 1 || uap->count > 2048)
+		return (EINVAL);
+
+	/* XXX: pre-validate accessibility to the whole of the UUID store? */
+
+	mtx_lock(&uuid_mutex);
+
+	uuid_node(uuid.node);
+	time = uuid_time();
+
+	if (uuid_last.time.ll == 0LL || uuid_last.node[0] != uuid.node[0] ||
+	    uuid_last.node[1] != uuid.node[1] ||
+	    uuid_last.node[2] != uuid.node[2])
+		uuid.seq = (uint16_t)arc4random() & 0x3fff;
+	else if (uuid_last.time.ll >= time)
+		uuid.seq = (uuid_last.seq + 1) & 0x3fff;
+	else
+		uuid.seq = uuid_last.seq;
+
+	uuid_last = uuid;
+	uuid_last.time.ll = (time + uap->count - 1) & ((1LL << 60) - 1LL);
+
+	mtx_unlock(&uuid_mutex);
+
+	/* Set sequence and variant and deal with byte order. */
+	uuid.seq = htobe16(uuid.seq | 0x8000);
+
+	/* XXX: this should copyout larger chunks at a time. */
+	do {
+		/* Set time and version (=1) and deal with byte order. */
+		uuid.time.x.low = (uint32_t)time;
+		uuid.time.x.mid = (uint16_t)(time >> 32);
+		uuid.time.x.hi = ((uint16_t)(time >> 48) & 0xfff) | (1 << 12);
+		error = copyout(&uuid, uap->store, sizeof(uuid));
+		uap->store++;
+		uap->count--;
+		time++;
+	} while (uap->count > 0 && !error);
+
+	return (error);
+}
+
+int
+snprintf_uuid(char *buf, size_t sz, struct uuid *uuid)
+{
+	struct uuid_private *id;
+	int cnt;
+
+	id = (struct uuid_private *)uuid;
+	cnt = snprintf(buf, sz, "%08x-%04x-%04x-%04x-%04x%04x%04x",
+	    id->time.x.low, id->time.x.mid, id->time.x.hi, be16toh(id->seq),
+	    be16toh(id->node[0]), be16toh(id->node[1]), be16toh(id->node[2]));
+	return (cnt);
+}
+
+int
+printf_uuid(struct uuid *uuid)
+{
+	char buf[38];
+
+	snprintf_uuid(buf, sizeof(buf), uuid);
+	return (printf("%s", buf));
+}
+
+int
+sbuf_printf_uuid(struct sbuf *sb, struct uuid *uuid)
+{
+	char buf[38];
+
+	snprintf_uuid(buf, sizeof(buf), uuid);
+	return (sbuf_printf(sb, "%s", buf));
+}
diff --git a/sys/kern/syscalls.c b/sys/kern/syscalls.c
index 7b0b49e..c555aca 100644
--- a/sys/kern/syscalls.c
+++ b/sys/kern/syscalls.c
@@ -3,7 +3,7 @@
  *
  * DO NOT EDIT-- this file is automatically generated.
  * $FreeBSD$
- * created from FreeBSD: src/sys/kern/syscalls.master,v 1.111 2002/05/05 23:37:44 mux Exp 
+ * created from FreeBSD: src/sys/kern/syscalls.master,v 1.112 2002/05/28 05:58:06 marcel Exp 
  */
 
 char *syscallnames[] = {
@@ -399,4 +399,5 @@ char *syscallnames[] = {
 	"#389",			/* 389 = __mac_set_file */
 	"kenv",			/* 390 = kenv */
 	"lchflags",			/* 391 = lchflags */
+	"uuidgen",			/* 392 = uuidgen */
 };
diff --git a/sys/sys/syscall.h b/sys/sys/syscall.h
index 31c0c9a..6fd04f3 100644
--- a/sys/sys/syscall.h
+++ b/sys/sys/syscall.h
@@ -3,7 +3,7 @@
  *
  * DO NOT EDIT-- this file is automatically generated.
  * $FreeBSD$
- * created from FreeBSD: src/sys/kern/syscalls.master,v 1.111 2002/05/05 23:37:44 mux Exp 
+ * created from FreeBSD: src/sys/kern/syscalls.master,v 1.112 2002/05/28 05:58:06 marcel Exp 
  */
 
 #define	SYS_syscall	0
@@ -305,4 +305,5 @@
 #define	SYS_kse_yield	383
 #define	SYS_kenv	390
 #define	SYS_lchflags	391
-#define	SYS_MAXSYSCALL	392
+#define	SYS_uuidgen	392
+#define	SYS_MAXSYSCALL	393
diff --git a/sys/sys/syscall.mk b/sys/sys/syscall.mk
index d269daf..193e7cc 100644
--- a/sys/sys/syscall.mk
+++ b/sys/sys/syscall.mk
@@ -1,7 +1,7 @@
 # FreeBSD system call names.
 # DO NOT EDIT-- this file is automatically generated.
 # $FreeBSD$
-# created from FreeBSD: src/sys/kern/syscalls.master,v 1.111 2002/05/05 23:37:44 mux Exp 
+# created from FreeBSD: src/sys/kern/syscalls.master,v 1.112 2002/05/28 05:58:06 marcel Exp 
 MIASM =  \
 	syscall.o \
 	exit.o \
@@ -254,4 +254,5 @@ MIASM =  \
 	thread_wakeup.o \
 	kse_yield.o \
 	kenv.o \
-	lchflags.o
+	lchflags.o \
+	uuidgen.o
diff --git a/sys/sys/sysproto.h b/sys/sys/sysproto.h
index 011dc92..57c6b7f 100644
--- a/sys/sys/sysproto.h
+++ b/sys/sys/sysproto.h
@@ -3,7 +3,7 @@
  *
  * DO NOT EDIT-- this file is automatically generated.
  * $FreeBSD$
- * created from FreeBSD: src/sys/kern/syscalls.master,v 1.111 2002/05/05 23:37:44 mux Exp 
+ * created from FreeBSD: src/sys/kern/syscalls.master,v 1.112 2002/05/28 05:58:06 marcel Exp 
  */
 
 #ifndef _SYS_SYSPROTO_H_
@@ -1115,6 +1115,10 @@ struct lchflags_args {
 	char path_l_[PADL_(const char *)]; const char * path; char path_r_[PADR_(const char *)];
 	char flags_l_[PADL_(int)]; int flags; char flags_r_[PADR_(int)];
 };
+struct uuidgen_args {
+	char store_l_[PADL_(struct uuid *)]; struct uuid * store; char store_r_[PADR_(struct uuid *)];
+	char count_l_[PADL_(int)]; int count; char count_r_[PADR_(int)];
+};
 int	nosys(struct thread *, struct nosys_args *);
 void	sys_exit(struct thread *, struct sys_exit_args *);
 int	fork(struct thread *, struct fork_args *);
@@ -1366,6 +1370,7 @@ int	thread_wakeup(struct thread *, struct thread_wakeup_args *);
 int	kse_yield(struct thread *, struct kse_yield_args *);
 int	kenv(struct thread *, struct kenv_args *);
 int	lchflags(struct thread *, struct lchflags_args *);
+int	uuidgen(struct thread *, struct uuidgen_args *);
 
 #ifdef COMPAT_43
 
diff --git a/sys/sys/uuid.h b/sys/sys/uuid.h
new file mode 100644
index 0000000..155f909
--- /dev/null
+++ b/sys/sys/uuid.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2002 Marcel Moolenaar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _SYS_UUID_H_
+#define	_SYS_UUID_H_
+
+/* Length of a node address (an IEEE 802 address). */
+#define	_UUID_NODE_LEN		6
+
+/*
+ * See also:
+ *      http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt
+ *      http://www.opengroup.org/onlinepubs/009629399/apdxa.htm
+ *
+ * A DCE 1.1 compatible source representation of UUIDs.
+ */
+struct uuid {
+	uint32_t	time_low;
+	uint16_t	time_mid;
+	uint16_t	time_hi_and_version;
+	uint8_t		clock_seq_hi_and_reserved;
+	uint8_t		clock_seq_low;
+	uint8_t		node[_UUID_NODE_LEN];
+};
+
+#ifdef _KERNEL
+
+#define	UUID_NODE_LEN	_UUID_NODE_LEN
+
+struct sbuf;
+
+int snprintf_uuid(char *, size_t, struct uuid *);
+int printf_uuid(struct uuid *);
+int sbuf_printf_uuid(struct sbuf *, struct uuid *);
+
+#else	/* _KERNEL */
+
+/* XXX namespace pollution? */
+typedef struct uuid uuid_t;
+
+int	uuidgen(struct uuid *, int);
+
+#endif	/* _KERNEL */
+
+#endif /* _SYS_UUID_H_ */
diff --git a/usr.bin/Makefile b/usr.bin/Makefile
index 892eb41..f49bbbc 100644
--- a/usr.bin/Makefile
+++ b/usr.bin/Makefile
@@ -178,6 +178,7 @@ SUBDIR=	apply \
 	users \
 	uudecode \
 	uuencode \
+	uuidgen \
 	vgrind \
 	vi \
 	vis \
diff --git a/usr.bin/uuidgen/Makefile b/usr.bin/uuidgen/Makefile
new file mode 100644
index 0000000..81459e2
--- /dev/null
+++ b/usr.bin/uuidgen/Makefile
@@ -0,0 +1,6 @@
+# $FreeBSD$
+
+PROG=	uuidgen
+WARNS?=	4
+
+.include <bsd.prog.mk>
diff --git a/usr.bin/uuidgen/uuidgen.1 b/usr.bin/uuidgen/uuidgen.1
new file mode 100644
index 0000000..d61f848
--- /dev/null
+++ b/usr.bin/uuidgen/uuidgen.1
@@ -0,0 +1,71 @@
+.\" Copyright (c) 2002 Marcel Moolenaar
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\"
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.\"
+.Dd May 23, 2002
+.Dt UUIDGEN 1
+.Os
+.Sh NAME
+.Nm uuidgen
+.Nd generate universally unique identifiers
+.Sh SYNOPSIS
+.Nm
+.Op Fl 1
+.Op Fl n Ar count
+.Sh DESCRIPTION
+The
+.Nm
+utility by default generates a single universally unique identifier (UUID),
+also known as a globally unique identifier (GUID). The UUID is written to
+stdout. The following options can be used to change the number of identifiers
+and the method used:
+.Bl -tag -width indent
+.It Fl 1
+This option only has effect if multiple identifiers are to be generated and
+instructs
+.Nm
+to not generate them in batch, but one at a time.
+.It Fl n
+This option controls the number of identifiers generated. By default, multiple
+identifiers are generated in batch.
+.El
+.Pp
+Batched generation yields a dense set of identifiers in such a way that there
+is no identifier that is larger than the smallest identifier in the set and
+smaller than the largest identifier in the set and that is not already in the
+set.
+.Pp
+When generating the identifiers one at a time, the identifiers will be close
+to each other, but operating system latency and processing time will be
+reflected in the distance between two successive identifiers.
+.Sh DIAGNOSTICS
+.Ex -std
+.Sh SEE ALSO
+.Xr uuidgen 2
+.Sh HISTORY
+The
+.Nm
+command first appeared in
+.Fx 5.0 .
diff --git a/usr.bin/uuidgen/uuidgen.c b/usr.bin/uuidgen/uuidgen.c
new file mode 100644
index 0000000..59fd446
--- /dev/null
+++ b/usr.bin/uuidgen/uuidgen.c
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2002 Marcel Moolenaar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $Id$
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/endian.h>
+#include <sys/uuid.h>
+
+#include <err.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static void
+usage(void)
+{
+	(void)fprintf(stderr, "usage: uuidgen [-1] [-n count]\n");
+	exit(1);
+}
+
+static void
+uuid_print(uuid_t *uuid)
+{
+	printf("%08x-%04x-%04x-%02x%02x-", uuid->time_low, uuid->time_mid,
+	    uuid->time_hi_and_version, uuid->clock_seq_hi_and_reserved,
+	    uuid->clock_seq_low);
+	printf("%02x%02x%02x%02x%02x%02x\n", uuid->node[0], uuid->node[1],
+	    uuid->node[2], uuid->node[3], uuid->node[4], uuid->node[5]);
+}
+
+int
+main(int argc, char *argv[])
+{
+	uuid_t *store, *uuid;
+	char *p;
+	int ch, count, i, iterate;
+
+	count = -1;	/* no count yet */
+	iterate = 0;	/* not one at a time */
+	while ((ch = getopt(argc, argv, "1n:")) != -1)
+		switch (ch) {
+		case '1':
+			iterate = 1;
+			break;
+		case 'n':
+			if (count > 0)
+				usage();
+			count = strtol(optarg, &p, 10);
+			if (*p != 0 || count < 1)
+				usage();
+			break;
+		default:
+			usage();
+		}
+	argv += optind;
+	argc -= optind;
+
+	if (argc)
+		usage();
+
+	if (count == -1)
+		count = 1;
+
+	store = (uuid_t*)malloc(sizeof(uuid_t) * count);
+	if (store == NULL)
+		err(1, "malloc()");
+
+	if (!iterate) {
+		/* Get them all in a single batch */
+		if (uuidgen(store, count) != 0)
+			err(1, "uuidgen()");
+	} else {
+		uuid = store;
+		for (i = 0; i < count; i++) {
+			if (uuidgen(uuid++, 1) != 0)
+				err(1, "uuidgen()");
+		}
+	}
+
+	uuid = store;
+	while (count--)
+		uuid_print(uuid++);
+
+	free(store);
+	return (0);
+}