/* $NetBSD: kern_uuid.c,v 1.17 2010/05/04 19:23:56 kardel 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 __KERNEL_RCSID(0, "$NetBSD: kern_uuid.c,v 1.17 2010/05/04 19:23:56 kardel Exp $"); #include #include #include #include #include #include #include /* NetBSD */ #include #include #include #include #include #include #include /* * 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; /* "UUID generator mutex lock" */ static kmutex_t uuid_mutex; void uuid_init(void) { mutex_init(&uuid_mutex, MUTEX_DEFAULT, IPL_NONE); } /* * 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, s; s = splnet(); KERNEL_LOCK(1, NULL); IFNET_FOREACH(ifp) { /* Walk the address list */ IFADDR_FOREACH(ifa, ifp) { sdl = (struct sockaddr_dl*)ifa->ifa_addr; if (sdl != NULL && sdl->sdl_family == AF_LINK && sdl->sdl_type == IFT_ETHER) { /* Got a MAC address. */ memcpy(node, CLLADDR(sdl), UUID_NODE_LEN); KERNEL_UNLOCK_ONE(NULL); splx(s); return; } } } KERNEL_UNLOCK_ONE(NULL); splx(s); for (i = 0; i < (UUID_NODE_LEN>>1); i++) node[i] = (uint16_t)arc4random(); *((uint8_t*)node) |= 0x01; } /* * 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 timespec tsp; uint64_t xtime = 0x01B21DD213814000LL; nanotime(&tsp); xtime += (uint64_t)tsp.tv_sec * 10000000LL; xtime += (uint64_t)(tsp.tv_nsec / 100); return (xtime & ((1LL << 60) - 1LL)); } /* * Internal routine to actually generate the UUID. */ static void uuid_generate(struct uuid_private *uuid, uint64_t *timep, int count) { uint64_t xtime; mutex_enter(&uuid_mutex); uuid_node(uuid->node); xtime = uuid_time(); *timep = xtime; 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 >= xtime) uuid->seq = (uuid_last.seq + 1) & 0x3fff; else uuid->seq = uuid_last.seq; uuid_last = *uuid; uuid_last.time.ll = (xtime + count - 1) & ((1LL << 60) - 1LL); mutex_exit(&uuid_mutex); } static int kern_uuidgen(struct uuid *store, int count, bool to_user) { struct uuid_private uuid; uint64_t xtime; int error = 0, i; KASSERT(count >= 1); /* Generate the base UUID. */ uuid_generate(&uuid, &xtime, count); /* Set sequence and variant and deal with byte order. */ uuid.seq = htobe16(uuid.seq | 0x8000); for (i = 0; i < count; xtime++, i++) { /* Set time and version (=1) and deal with byte order. */ uuid.time.x.low = (uint32_t)xtime; uuid.time.x.mid = (uint16_t)(xtime >> 32); uuid.time.x.hi = ((uint16_t)(xtime >> 48) & 0xfff) | (1 << 12); if (to_user) { error = copyout(&uuid, store + i, sizeof(uuid)); if (error != 0) break; } else { memcpy(store + i, &uuid, sizeof(uuid)); } } return error; } int sys_uuidgen(struct lwp *l, const struct sys_uuidgen_args *uap, register_t *retval) { /* * 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); return kern_uuidgen(SCARG(uap, store), SCARG(uap,count), true); } int uuidgen(struct uuid *store, int count) { return kern_uuidgen(store,count, false); } int uuid_snprintf(char *buf, size_t sz, const struct uuid *uuid) { const struct uuid_private *id; int cnt; id = (const 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 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]; }