/* $NetBSD: kern_uuid.c,v 1.20 2014/10/05 10:00:03 riastradh Exp $ */

/* $NetBSD: kern_uuid.c,v 1.20 2014/10/05 10:00:03 riastradh Exp $ */

/*
* 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: /repoman/r/ncvs/src/sys/kern/kern_uuid.c,v 1.7 2004/01/12 13:34:11 rse Exp $
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: kern_uuid.c,v 1.20 2014/10/05 10:00:03 riastradh Exp $");

#include <sys/param.h>
#include <sys/cprng.h>
#include <sys/endian.h>
#include <sys/syscallargs.h>
#include <sys/systm.h>
#include <sys/uuid.h>

/*
* See also:
* http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt
* http://www.opengroup.org/onlinepubs/009629399/apdxa.htm
*/

CTASSERT(sizeof(struct uuid) == 16);

static void
uuid_generate(struct uuid *uuid)
{

/* Randomly generate the content. */
cprng_fast(uuid, sizeof(*uuid));

/* Set the version number to 4. */
uuid->time_hi_and_version &= ~(uint32_t)0xf000;
uuid->time_hi_and_version |= 0x4000;

/* Fix the reserved bits. */
uuid->clock_seq_hi_and_reserved &= ~(uint8_t)0x40;
uuid->clock_seq_hi_and_reserved |= 0x80;
}

int
sys_uuidgen(struct lwp *l, const struct sys_uuidgen_args *uap, register_t *retval)
{
struct uuid *store, tmp;
unsigned count;
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 (SCARG(uap,count) < 1 || SCARG(uap,count) > 2048)
return (EINVAL);

for (store = SCARG(uap,store), count = SCARG(uap,count);
count > 0;
store++, count--) {
uuid_generate(&tmp);
error = copyout(&tmp, store, sizeof tmp);
if (error)
return error;
}

return 0;
}

int
uuidgen(struct uuid *store, int count)
{

while (--count > 0)
uuid_generate(store++);
return 0;
}

int
uuid_snprintf(char *buf, size_t sz, const struct uuid *uuid)
{

return snprintf(buf, sz,
"%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
uuid->time_low, uuid->time_mid, uuid->time_hi_and_version,
uuid->clock_seq_hi_and_reserved, uuid->clock_seq_low,
uuid->node[0], uuid->node[1], uuid->node[2], uuid->node[3],
uuid->node[4], uuid->node[5]);
}

int
uuid_printf(const struct uuid *uuid)
{
char buf[UUID_STR_LEN];

(void) uuid_snprintf(buf, sizeof(buf), uuid);
printf("%s", buf);
return (0);
}

/*
* Encode/Decode UUID into octet-stream.
* http://www.opengroup.org/dce/info/draft-leach-uuids-guids-01.txt
*
* 0 1 2 3
* 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | time_low |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | time_mid | time_hi_and_version |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |clk_seq_hi_res | clk_seq_low | node (0-1) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | node (2-5) |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/

void
uuid_enc_le(void *buf, const struct uuid *uuid)
{
uint8_t *p = buf;
int i;

le32enc(p, uuid->time_low);
le16enc(p + 4, uuid->time_mid);
le16enc(p + 6, uuid->time_hi_and_version);
p[8] = uuid->clock_seq_hi_and_reserved;
p[9] = uuid->clock_seq_low;
for (i = 0; i < _UUID_NODE_LEN; i++)
p[10 + i] = uuid->node[i];
}

void
uuid_dec_le(void const *buf, struct uuid *uuid)
{
const uint8_t *p = buf;
int i;

uuid->time_low = le32dec(p);
uuid->time_mid = le16dec(p + 4);
uuid->time_hi_and_version = le16dec(p + 6);
uuid->clock_seq_hi_and_reserved = p[8];
uuid->clock_seq_low = p[9];
for (i = 0; i < _UUID_NODE_LEN; i++)
uuid->node[i] = p[10 + i];
}

void
uuid_enc_be(void *buf, const struct uuid *uuid)
{
uint8_t *p = buf;
int i;

be32enc(p, uuid->time_low);
be16enc(p + 4, uuid->time_mid);
be16enc(p + 6, uuid->time_hi_and_version);
p[8] = uuid->clock_seq_hi_and_reserved;
p[9] = uuid->clock_seq_low;
for (i = 0; i < _UUID_NODE_LEN; i++)
p[10 + i] = uuid->node[i];
}

void
uuid_dec_be(void const *buf, struct uuid *uuid)
{
const uint8_t *p = buf;
int i;

uuid->time_low = be32dec(p);
uuid->time_mid = be16dec(p + 4);
uuid->time_hi_and_version = be16dec(p + 6);
uuid->clock_seq_hi_and_reserved = p[8];
uuid->clock_seq_low = p[9];
for (i = 0; i < _UUID_NODE_LEN; i++)
uuid->node[i] = p[10 + i];
}