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FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //sys/kern/kern_uuid.c |
/*-
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/sys/kern/kern_uuid.c 233200 2012-03-19 20:49:16Z jhb $");
#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/systm.h>
#include <sys/jail.h>
#include <sys/uuid.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/vnet.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;
CURVNET_SET(TD_TO_VNET(curthread));
IFNET_RLOCK_NOSLEEP();
TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
/* Walk the address list */
IF_ADDR_RLOCK(ifp);
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);
IF_ADDR_RUNLOCK(ifp);
IFNET_RUNLOCK_NOSLEEP();
CURVNET_RESTORE();
return;
}
}
IF_ADDR_RUNLOCK(ifp);
}
IFNET_RUNLOCK_NOSLEEP();
for (i = 0; i < (UUID_NODE_LEN>>1); i++)
node[i] = (uint16_t)arc4random();
*((uint8_t*)node) |= 0x01;
CURVNET_RESTORE();
}
/*
* 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, January 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));
}
struct uuid *
kern_uuidgen(struct uuid *store, size_t count)
{
struct uuid_private uuid;
uint64_t time;
size_t n;
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 + count - 1) & ((1LL << 60) - 1LL);
mtx_unlock(&uuid_mutex);
/* Set sequence and variant and deal with byte order. */
uuid.seq = htobe16(uuid.seq | 0x8000);
for (n = 0; n < count; n++) {
/* Set time and version (=1). */
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);
store[n] = *(struct uuid *)&uuid;
time++;
}
return (store);
}
#ifndef _SYS_SYSPROTO_H_
struct uuidgen_args {
struct uuid *store;
int count;
};
#endif
int
sys_uuidgen(struct thread *td, struct uuidgen_args *uap)
{
struct uuid *store;
size_t 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 probably needs to be tunable.
*/
if (uap->count < 1 || uap->count > 2048)
return (EINVAL);
count = uap->count;
store = malloc(count * sizeof(struct uuid), M_TEMP, M_WAITOK);
kern_uuidgen(store, count);
error = copyout(store, uap->store, count * sizeof(struct uuid));
free(store, M_TEMP);
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));
}
/*
* Encode/Decode UUID into byte-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
le_uuid_enc(void *buf, struct uuid const *uuid)
{
u_char *p;
int i;
p = buf;
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
le_uuid_dec(void const *buf, struct uuid *uuid)
{
u_char const *p;
int i;
p = buf;
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
be_uuid_enc(void *buf, struct uuid const *uuid)
{
u_char *p;
int i;
p = buf;
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
be_uuid_dec(void const *buf, struct uuid *uuid)
{
u_char const *p;
int i;
p = buf;
uuid->time_low = be32dec(p);
uuid->time_mid = le16dec(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];
}
int
parse_uuid(const char *str, struct uuid *uuid)
{
u_int c[11];
int n;
/* An empty string represents a nil UUID. */
if (*str == '\0') {
bzero(uuid, sizeof(*uuid));
return (0);
}
/* The UUID string representation has a fixed length. */
if (strlen(str) != 36)
return (EINVAL);
/*
* We only work with "new" UUIDs. New UUIDs have the form:
* 01234567-89ab-cdef-0123-456789abcdef
* The so called "old" UUIDs, which we don't support, have the form:
* 0123456789ab.cd.ef.01.23.45.67.89.ab
*/
if (str[8] != '-')
return (EINVAL);
n = sscanf(str, "%8x-%4x-%4x-%2x%2x-%2x%2x%2x%2x%2x%2x", c + 0, c + 1,
c + 2, c + 3, c + 4, c + 5, c + 6, c + 7, c + 8, c + 9, c + 10);
/* Make sure we have all conversions. */
if (n != 11)
return (EINVAL);
/* Successful scan. Build the UUID. */
uuid->time_low = c[0];
uuid->time_mid = c[1];
uuid->time_hi_and_version = c[2];
uuid->clock_seq_hi_and_reserved = c[3];
uuid->clock_seq_low = c[4];
for (n = 0; n < 6; n++)
uuid->node[n] = c[n + 5];
/* Check semantics... */
return (((c[3] & 0x80) != 0x00 && /* variant 0? */
(c[3] & 0xc0) != 0x80 && /* variant 1? */
(c[3] & 0xe0) != 0xc0) ? EINVAL : 0); /* variant 2? */
}