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nuttx/net/sixlowpan/sixlowpan_utils.c

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/****************************************************************************
* net/sixlowpan/sixlowpan_utils.c
*
* Copyright (C) 2017 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Derives from logic in Contiki:
*
* Copyright (c) 2008, Swedish Institute of Computer Science.
* All rights reserved.
* Authors: Adam Dunkels <adam@sics.se>
* Nicolas Tsiftes <nvt@sics.se>
* Niclas Finne <nfi@sics.se>
* Mathilde Durvy <mdurvy@cisco.com>
* Julien Abeille <jabeille@cisco.com>
* Joakim Eriksson <joakime@sics.se>
* Joel Hoglund <joel@sics.se>
*
* 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.
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE OR CONTRIBUTORS 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/net/ip.h>
#include <nuttx/net/radiodev.h>
#include <nuttx/net/sixlowpan.h>
#include <nuttx/wireless/pktradio.h>
#include <nuttx/wireless/ieee802154/ieee802154_mac.h>
#include "inet/inet.h"
#include "sixlowpan/sixlowpan_internal.h"
#ifdef CONFIG_NET_6LOWPAN
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* REVISIT: The setting CONFIG_PKTRADIO_ADDRLEN should be the *maximum*
* address length. If there is only a single packet radio then it should be
* the exact address length of that radio. If there are multiple packet
* radios with different address lengths, then it will be inexact; it will
* be the size of the longest address.
*/
#undef HAVE_BYTEADDR
#undef HAVE_SADDR
#undef HAVE_EADDR
#ifdef CONFIG_WIRELESS_IEEE802154
# define HAVE_SADDR 1
# define HAVE_EADDR 1
#endif
#ifdef CONFIG_WIRELESS_PKTRADIO
# if CONFIG_PKTRADIO_ADDRLEN == 1
# define HAVE_BYTEADDR 1
# elif CONFIG_PKTRADIO_ADDRLEN == 2
# define HAVE_BYTEADDR 1
# define HAVE_SADDR 1
# elif CONFIG_PKTRADIO_ADDRLEN == 8
# define HAVE_BYTEADDR 1
# define HAVE_SADDR 1
# define HAVE_EADDR 1
# else
# error Unsupported value for CONFIG_PKTRADIO_ADDRLEN
# endif
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: sixlowpan_[s|e]addrfromip
*
* Description:
* sixlowpan_[s|e]addrfromip(): Extract the IEEE 802.15.14 address from a
* MAC-based IPv6 address. sixlowpan_saddrfromip() and
* sixlowpan_eaddrfromip() handle short and extended addresses,
* respectively.
*
* 128 112 96 80 64 48 32 16
* ---- ---- ---- ---- ---- ---- ---- ----
* fe80 0000 0000 0000 0000 00ff fe00 xx00 1-byte short address IEEE 48-bit MAC
* xxxx 0000 0000 0000 0000 00ff fe00 xxxx 2-byte short address IEEE 48-bit MAC
* xxxx 0000 0000 0000 xxxx xxxx xxxx xxxx 8-byte extended address IEEE EUI-64
*
****************************************************************************/
#ifndef CONFIG_NET_STARPOINT
#ifdef HAVE_BYTEADDR
static void sixlowpan_baddrfromip(const net_ipv6addr_t ipaddr, FAR uint8_t *baddr)
{
/* Big-endian uint16_t to byte order */
baddr[0] = ipaddr[7] >> 8 ^ 0x02;
}
#endif
#ifdef HAVE_SADDR
static void sixlowpan_saddrfromip(const net_ipv6addr_t ipaddr, FAR uint8_t *saddr)
{
/* Big-endian uint16_t to byte order */
saddr[0] = ipaddr[7] >> 8;
saddr[1] = ipaddr[7] & 0xff;
saddr[0] ^= 0x02;
}
#endif
#ifdef HAVE_EADDR
static void sixlowpan_eaddrfromip(const net_ipv6addr_t ipaddr, FAR uint8_t *eaddr)
{
FAR uint8_t *eptr = eaddr;
int i;
DEBUGASSERT(ipaddr[0] == HTONS(0xfe80));
for (i = 4; i < 8; i++)
{
/* Big-endian uint16_t to byte order */
*eptr++ = ipaddr[i] >> 8;
*eptr++ = ipaddr[i] & 0xff;
}
eaddr[0] ^= 0x02;
}
#endif
#endif /* !CONFIG_NET_STARPOINT */
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sixlowpan_destaddrfromip
*
* Description:
* sixlowpan_destaddrfromip(): Extract the IEEE 802.15.14 destination
* address from a MAC-based destination IPv6 address. This function
* handles a tagged address union which may either a short or and
* extended destination address.
*
* 128 112 96 80 64 48 32 16
* ---- ---- ---- ---- ---- ---- ---- ----
* ff02 xxxx xxxx xxxx xxxx xxxx xxxx xxxx Multicast
* ff02 0000 0000 0000 0000 0000 0000 0001 All nodes multicast group
* xxxx 0000 0000 0000 0000 00ff fe00 xx00 1-byte short address IEEE 48-bit MAC
* xxxx 0000 0000 0000 0000 00ff fe00 xxxx 2-byte short address IEEE 48-bit MAC
* xxxx 0000 0000 0000 xxxx xxxx xxxx xxxx 8-byte extended address IEEE EUI-64
*
* In the case there the IEEE 802.15.4 node functions as an endpoint in a
* start topology, the destination address will, instead, be the address
* of the star hub (which is assumed to be the address of the cooordinator).
*
****************************************************************************/
int sixlowpan_destaddrfromip(FAR struct radio_driver_s *radio,
const net_ipv6addr_t ipaddr,
FAR struct netdev_varaddr_s *destaddr)
{
struct radiodev_properties_s properties;
int ret;
#ifdef CONFIG_NET_STARPOINT
/* Only the radio driver knows the correct address of the hub. For IEEE
* 802.15.4 this will be the address of the PAN coordinator. For other
* radios, this may be some configured, "well-known" address.
*/
DEBUGASSERT(radio->r_properties != NULL);
ret = radio->r_properties(radio, &properties);
if (ret < 0)
{
return ret;
}
memcpy(destaddr, &properties.sp_hubnode, sizeof(struct netdev_varaddr_s));
return OK;
#else /* CONFIG_NET_STARPOINT */
/* Check for a multicast address */
if (ipaddr[0] == HTONS(0xff02))
{
DEBUGASSERT(radio->r_properties != NULL);
ret = radio->r_properties(radio, &properties);
if (ret < 0)
{
return ret;
}
/* Check for the broadcast IP address
*
* IPv6 does not implement the method of broadcast, and therefore
* does not define broadcast addresses. Instead, IPv6 uses multicast
* addressing to the all-nodes multicast group: ff02:0:0:0:0:0:0:1.
*
* However, the use of the all-nodes group is not common, and most
* IPv6 protocols use a dedicated link-local multicast group to avoid
* disturbing every interface in the network.
*/
if (net_ipv6addr_cmp(ipaddr, g_ipv6_allnodes))
{
memcpy(destaddr, &properties.sp_bcast,
sizeof(struct netdev_varaddr_s));
}
else
{
memcpy(destaddr, &properties.sp_mcast,
sizeof(struct netdev_varaddr_s));
}
return OK;
}
/* Otherwise, the destination MAC address is encoded in the IP address */
/* Check for compressible link-local address.
* REVISIT: This should not restrict us to link-local addresses.
*/
if (ipaddr[0] != HTONS(0xfe80) || ipaddr[1] != 0 ||
ipaddr[2] != 0 || ipaddr[3] != 0)
{
return -EADDRNOTAVAIL;
}
#ifdef CONFIG_WIRELESS_PKTRADIO
/* If this is a packet radio, then we cannot know the correct size of the
* radio's MAC address without asking. The setting CONFIG_PKTRADIO_ADDRLEN
* is inexact if there are multiple packet radios with different address
* lengths; it that case it will be the size of the longest address.
*
* NOTE: This logic assumes that the packet radio's address length is a
* constant.
*/
#ifdef CONFIG_WIRELESS_IEEE802154
if (radio->r_dev.d_lltype == NET_LL_PKTRADIO)
#endif
{
DEBUGASSERT(radio->r_properties != NULL);
ret = radio->r_properties(radio, &properties);
if (ret < 0)
{
return ret;
}
#ifdef HAVE_BYTEADDR
if (properties.sp_addrlen == 1 &&
SIXLOWPAN_IS_IID_8BIT_COMPRESSABLE(ipaddr))
{
memset(destaddr, 0, sizeof(struct netdev_varaddr_s));
sixlowpan_baddrfromip(ipaddr, destaddr->nv_addr);
destaddr->nv_addrlen = 1;
return OK;
}
else
#endif
#ifdef HAVE_SADDR
if (properties.sp_addrlen == 2 &&
SIXLOWPAN_IS_IID_16BIT_COMPRESSABLE(ipaddr))
{
memset(destaddr, 0, sizeof(struct netdev_varaddr_s));
sixlowpan_saddrfromip(ipaddr, destaddr->nv_addr);
destaddr->nv_addrlen = 2;
return OK;
}
else
#endif
#ifdef HAVE_EADDR
if (properties.sp_addrlen == 8)
{
sixlowpan_eaddrfromip(ipaddr, destaddr->nv_addr);
destaddr->nv_addrlen = 8;
return OK;
}
else
#endif
{
/* Just to satisfy the last dangling 'else' */
}
return -EADDRNOTAVAIL;
}
#endif /* CONFIG_WIRELESS_PKTRADIO */
#ifdef CONFIG_WIRELESS_IEEE802154
#ifdef CONFIG_WIRELESS_PKTRADIO
else
#endif
{
if (SIXLOWPAN_IS_IID_16BIT_COMPRESSABLE(ipaddr))
{
memset(destaddr, 0, sizeof(struct netdev_varaddr_s));
sixlowpan_saddrfromip(ipaddr, destaddr->nv_addr);
destaddr->nv_addrlen = NET_6LOWPAN_SADDRSIZE;
}
else
{
sixlowpan_eaddrfromip(ipaddr, destaddr->nv_addr);
destaddr->nv_addrlen = NET_6LOWPAN_EADDRSIZE;
}
return OK;
}
#endif /* CONFIG_WIRELESS_IEEE802154 */
#endif /* CONFIG_NET_STARPOINT */
}
/****************************************************************************
* Name: sixlowpan_ipfromaddr (plus helpers)
*
* Description:
* sixlowpan_ipfrom[s|e]addr(): Create a link-local, MAC-based IPv6
* address from an IEEE802.15.4 short address (saddr), extended address
* (eaddr), or other variable length radio addresses.
*
* 128 112 96 80 64 48 32 16
* ---- ---- ---- ---- ---- ---- ---- ----
* fe80 0000 0000 0000 0000 00ff fe00 xx00 1-byte short address IEEE 48-bit MAC
* fe80 0000 0000 0000 0000 00ff fe00 xxxx 2-byte short address IEEE 48-bit MAC
* fe80 0000 0000 0000 xxxx xxxx xxxx xxxx 8-byte extended address IEEE EUI-64
*
****************************************************************************/
#ifdef HAVE_BYTEADDR
static inline void sixlowpan_ipfrombyte(FAR const uint8_t *byte,
FAR net_ipv6addr_t ipaddr)
{
ipaddr[0] = HTONS(0xfe80);
ipaddr[1] = 0;
ipaddr[2] = 0;
ipaddr[3] = 0;
ipaddr[4] = 0;
ipaddr[5] = HTONS(0x00ff);
ipaddr[6] = HTONS(0xfe00);
ipaddr[7] = (uint16_t)byte[0] << 8 ^ 0x0200;
}
#endif
#ifdef HAVE_SADDR
static inline void sixlowpan_ipfromsaddr(FAR const uint8_t *saddr,
FAR net_ipv6addr_t ipaddr)
{
ipaddr[0] = HTONS(0xfe80);
ipaddr[1] = 0;
ipaddr[2] = 0;
ipaddr[3] = 0;
ipaddr[4] = 0;
ipaddr[5] = HTONS(0x00ff);
ipaddr[6] = HTONS(0xfe00);
ipaddr[7] = (uint16_t)saddr[0] << 8 | (uint16_t)saddr[1];
ipaddr[7] ^= 0x0200;
}
#endif
#ifdef HAVE_EADDR
static inline void sixlowpan_ipfromeaddr(FAR const uint8_t *eaddr,
FAR net_ipv6addr_t ipaddr)
{
ipaddr[0] = HTONS(0xfe80);
ipaddr[1] = 0;
ipaddr[2] = 0;
ipaddr[3] = 0;
ipaddr[4] = (uint16_t)eaddr[0] << 8 | (uint16_t)eaddr[1];
ipaddr[5] = (uint16_t)eaddr[2] << 8 | (uint16_t)eaddr[3];
ipaddr[6] = (uint16_t)eaddr[4] << 8 | (uint16_t)eaddr[5];
ipaddr[7] = (uint16_t)eaddr[6] << 8 | (uint16_t)eaddr[7];
ipaddr[4] ^= 0x0200;
}
#endif
void sixlowpan_ipfromaddr(FAR const struct netdev_varaddr_s *addr,
FAR net_ipv6addr_t ipaddr)
{
switch (addr->nv_addrlen)
{
#ifdef HAVE_BYTEADDR
case 1:
sixlowpan_ipfrombyte(addr->nv_addr, ipaddr);
break;
#endif
#ifdef HAVE_SADDR
case NET_6LOWPAN_SADDRSIZE:
sixlowpan_ipfromsaddr(addr->nv_addr, ipaddr);
break;
#endif
#ifdef HAVE_EADDR
case NET_6LOWPAN_EADDRSIZE:
sixlowpan_ipfromeaddr(addr->nv_addr, ipaddr);
break;
#endif
default:
nerr("ERROR: Unsupported address length: %u\n", addr->nv_addrlen);
break;
}
}
/****************************************************************************
* Name: sixlowpan_ismacbased (and helpers)
*
* Description:
* sixlowpan_ismacbased() will return true for IP addresses formed from
* IEEE802.15.4 MAC addresses. sixlowpan_destaddrfromip() is intended to
* handle a tagged address or any size.
*
* 128 112 96 80 64 48 32 16
* ---- ---- ---- ---- ---- ---- ---- ----
* fe80 0000 0000 0000 0000 00ff fe00 xx00 1-byte short address IEEE 48-bit MAC
* fe80 0000 0000 0000 0000 00ff fe00 xxxx 2-byte short address IEEE 48-bit MAC
* fe80 0000 0000 0000 xxxx xxxx xxxx xxxx 8-byte extended address IEEE EUI-64
*
****************************************************************************/
#ifdef HAVE_BYTEADDR
static inline bool sixlowpan_isbytebased(const net_ipv6addr_t ipaddr,
uint8_t byte)
{
return (ipaddr[5] == HTONS(0x00ff) &&
ipaddr[6] == HTONS(0xfe00) &&
ipaddr[7] == (((uint16_t)byte << 8) ^ 0x0200));
}
#endif
static inline bool sixlowpan_issaddrbased(const net_ipv6addr_t ipaddr,
FAR const uint8_t *saddr)
{
return (ipaddr[5] == HTONS(0x00ff) &&
ipaddr[6] == HTONS(0xfe00) &&
ipaddr[7] == (GETUINT16(saddr, 0) ^ 0x0200));
}
static inline bool sixlowpan_iseaddrbased(const net_ipv6addr_t ipaddr,
FAR const uint8_t *eaddr)
{
return (ipaddr[4] == (GETUINT16(eaddr, 0) ^ 0x0200) &&
ipaddr[5] == GETUINT16(eaddr, 2) &&
ipaddr[6] == GETUINT16(eaddr, 4) &&
ipaddr[7] == GETUINT16(eaddr, 6));
}
bool sixlowpan_ismacbased(const net_ipv6addr_t ipaddr,
FAR const struct netdev_varaddr_s *addr)
{
switch (addr->nv_addrlen)
{
#ifdef HAVE_BYTEADDR
case 1:
return sixlowpan_isbytebased(ipaddr, addr->nv_addr[0]);
#endif
#ifdef HAVE_SADDR
case NET_6LOWPAN_SADDRSIZE:
return sixlowpan_issaddrbased(ipaddr, addr->nv_addr);
#endif
#ifdef HAVE_EADDR
case NET_6LOWPAN_EADDRSIZE:
return sixlowpan_iseaddrbased(ipaddr, addr->nv_addr);
#endif
default:
nerr("ERROR: Unsupported address length: %u\n", addr->nv_addrlen);
return false;
}
}
/****************************************************************************
* Name: sixlowpan_src_panid
*
* Description:
* Get the source PAN ID from the IEEE802.15.4 MAC layer.
*
* Input parameters:
* radio - Reference to a radio network driver state instance.
* panid - The location in which to return the PAN ID. 0xfff may be
* returned if the device is not associated.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
#ifdef CONFIG_WIRELESS_IEEE802154
int sixlowpan_src_panid(FAR struct radio_driver_s *radio,
FAR uint8_t *panid)
{
FAR struct net_driver_s *dev = &radio->r_dev;
struct ieee802154_netmac_s arg;
int ret;
memcpy(arg.ifr_name, radio->r_dev.d_ifname, IFNAMSIZ);
arg.u.getreq.attr = IEEE802154_ATTR_MAC_PANID;
ret = dev->d_ioctl(dev, MAC802154IOC_MLME_GET_REQUEST,
(unsigned long)((uintptr_t)&arg));
if (ret < 0)
{
nerr("ERROR: MAC802154IOC_MLME_GET_REQUEST failed: %d\n", ret);
return ret;
}
IEEE802154_PANIDCOPY(panid, arg.u.getreq.attrval.mac.panid);
return OK;
}
#endif
/****************************************************************************
* Name: sixlowpan_extract_srcaddr
*
* Description:
* Extract the source MAC address from the radio-specific RX metadata, and
* return the source address in a radio-agnostic form.
*
* Input parameters:
* radio - Reference to a radio network driver state instance.
* metadata - Opaque reference to the radio-specific RX metadata.
* srcaddr - The location in which to return the source MAC address.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int sixlowpan_extract_srcaddr(FAR struct radio_driver_s *radio,
FAR const void *metadata,
FAR struct netdev_varaddr_s *srcaddr)
{
DEBUGASSERT(radio != NULL && metadata != NULL && srcaddr != NULL);
#ifdef CONFIG_WIRELESS_IEEE802154
#ifdef CONFIG_WIRELESS_PKTRADIO
if (radio->r_dev.d_lltype == NET_LL_IEEE802154)
#endif
{
FAR const struct ieee802154_data_ind_s *ind =
(FAR const struct ieee802154_data_ind_s *)metadata;
if (ind->src.mode == IEEE802154_ADDRMODE_SHORT)
{
srcaddr->nv_addrlen = NET_6LOWPAN_SADDRSIZE;
memcpy(srcaddr->nv_addr, ind->src.saddr, NET_6LOWPAN_SADDRSIZE);
}
else
{
srcaddr->nv_addrlen = NET_6LOWPAN_EADDRSIZE;
memcpy(srcaddr->nv_addr, ind->src.eaddr, NET_6LOWPAN_EADDRSIZE);
}
return OK;
}
#endif
#ifdef CONFIG_WIRELESS_PKTRADIO
#ifdef CONFIG_WIRELESS_IEEE802154
else
#endif
{
FAR const struct pktradio_metadata_s *pktmeta =
(FAR const struct pktradio_metadata_s *)metadata;
DEBUGASSERT(pktmeta->pm_src.pa_addrlen <= CONFIG_PKTRADIO_ADDRLEN);
srcaddr->nv_addrlen = pktmeta->pm_src.pa_addrlen;
memcpy(srcaddr->nv_addr, pktmeta->pm_src.pa_addr,
pktmeta->pm_src.pa_addrlen);
return OK;
}
#endif
return -EINVAL; /* Shouldn't get here */
}
/****************************************************************************
* Name: sixlowpan_extract_destaddr
*
* Description:
* Extract the destination MAC address from the radio-specific RX metadata,
* and return the destination address in a radio-agnostic form.
*
* Input parameters:
* radio - Reference to a radio network driver state instance.
* metadata - Opaque reference to the radio-specific RX metadata.
* destaddr - The location in which to return the destination MAC address.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
int sixlowpan_extract_destaddr(FAR struct radio_driver_s *radio,
FAR const void *metadata,
FAR struct netdev_varaddr_s *destaddr)
{
DEBUGASSERT(radio != NULL && metadata != NULL && destaddr != NULL);
#ifdef CONFIG_WIRELESS_IEEE802154
#ifdef CONFIG_WIRELESS_PKTRADIO
if (radio->r_dev.d_lltype == NET_LL_IEEE802154)
#endif
{
FAR const struct ieee802154_data_ind_s *ind =
(FAR const struct ieee802154_data_ind_s *)metadata;
if (ind->dest.mode == IEEE802154_ADDRMODE_SHORT)
{
destaddr->nv_addrlen = NET_6LOWPAN_SADDRSIZE;
memcpy(destaddr->nv_addr, ind->dest.saddr, NET_6LOWPAN_SADDRSIZE);
}
else
{
destaddr->nv_addrlen = NET_6LOWPAN_EADDRSIZE;
memcpy(destaddr->nv_addr, ind->dest.eaddr, NET_6LOWPAN_EADDRSIZE);
}
return OK;
}
#endif
#ifdef CONFIG_WIRELESS_PKTRADIO
#ifdef CONFIG_WIRELESS_IEEE802154
else
#endif
{
FAR const struct pktradio_metadata_s *pktmeta =
(FAR const struct pktradio_metadata_s *)metadata;
DEBUGASSERT(pktmeta->pm_dest.pa_addrlen <= CONFIG_PKTRADIO_ADDRLEN);
destaddr->nv_addrlen = pktmeta->pm_dest.pa_addrlen;
memcpy(destaddr->nv_addr, pktmeta->pm_dest.pa_addr,
pktmeta->pm_dest.pa_addrlen);
return OK;
}
#endif
return -EINVAL; /* Shouldn't get here */
}
#endif /* CONFIG_NET_6LOWPAN */
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