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linux/net/ipv6/datagram.c

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/*
* common UDP/RAW code
* Linux INET6 implementation
*
* Authors:
* Pedro Roque <roque@di.fc.ul.pt>
*
* $Id: datagram.c,v 1.24 2002/02/01 22:01:04 davem Exp $
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in6.h>
#include <linux/ipv6.h>
#include <linux/route.h>
#include <net/ipv6.h>
#include <net/ndisc.h>
#include <net/addrconf.h>
#include <net/transp_v6.h>
#include <net/ip6_route.h>
#include <net/tcp_states.h>
#include <linux/errqueue.h>
#include <asm/uaccess.h>
int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
struct inet_sock *inet = inet_sk(sk);
struct ipv6_pinfo *np = inet6_sk(sk);
struct in6_addr *daddr, *final_p = NULL, final;
struct dst_entry *dst;
struct flowi fl;
struct ip6_flowlabel *flowlabel = NULL;
int addr_type;
int err;
if (usin->sin6_family == AF_INET) {
if (__ipv6_only_sock(sk))
return -EAFNOSUPPORT;
err = ip4_datagram_connect(sk, uaddr, addr_len);
goto ipv4_connected;
}
if (addr_len < SIN6_LEN_RFC2133)
return -EINVAL;
if (usin->sin6_family != AF_INET6)
return -EAFNOSUPPORT;
memset(&fl, 0, sizeof(fl));
if (np->sndflow) {
fl.fl6_flowlabel = usin->sin6_flowinfo&IPV6_FLOWINFO_MASK;
if (fl.fl6_flowlabel&IPV6_FLOWLABEL_MASK) {
flowlabel = fl6_sock_lookup(sk, fl.fl6_flowlabel);
if (flowlabel == NULL)
return -EINVAL;
ipv6_addr_copy(&usin->sin6_addr, &flowlabel->dst);
}
}
addr_type = ipv6_addr_type(&usin->sin6_addr);
if (addr_type == IPV6_ADDR_ANY) {
/*
* connect to self
*/
usin->sin6_addr.s6_addr[15] = 0x01;
}
daddr = &usin->sin6_addr;
if (addr_type == IPV6_ADDR_MAPPED) {
struct sockaddr_in sin;
if (__ipv6_only_sock(sk)) {
err = -ENETUNREACH;
goto out;
}
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = daddr->s6_addr32[3];
sin.sin_port = usin->sin6_port;
err = ip4_datagram_connect(sk,
(struct sockaddr*) &sin,
sizeof(sin));
ipv4_connected:
if (err)
goto out;
ipv6_addr_set(&np->daddr, 0, 0, htonl(0x0000ffff), inet->daddr);
if (ipv6_addr_any(&np->saddr)) {
ipv6_addr_set(&np->saddr, 0, 0, htonl(0x0000ffff),
inet->saddr);
}
if (ipv6_addr_any(&np->rcv_saddr)) {
ipv6_addr_set(&np->rcv_saddr, 0, 0, htonl(0x0000ffff),
inet->rcv_saddr);
}
goto out;
}
if (addr_type&IPV6_ADDR_LINKLOCAL) {
if (addr_len >= sizeof(struct sockaddr_in6) &&
usin->sin6_scope_id) {
if (sk->sk_bound_dev_if &&
sk->sk_bound_dev_if != usin->sin6_scope_id) {
err = -EINVAL;
goto out;
}
sk->sk_bound_dev_if = usin->sin6_scope_id;
}
if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
sk->sk_bound_dev_if = np->mcast_oif;
/* Connect to link-local address requires an interface */
if (!sk->sk_bound_dev_if) {
err = -EINVAL;
goto out;
}
}
ipv6_addr_copy(&np->daddr, daddr);
np->flow_label = fl.fl6_flowlabel;
inet->dport = usin->sin6_port;
/*
* Check for a route to destination an obtain the
* destination cache for it.
*/
fl.proto = sk->sk_protocol;
ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
ipv6_addr_copy(&fl.fl6_src, &np->saddr);
fl.oif = sk->sk_bound_dev_if;
fl.fl_ip_dport = inet->dport;
fl.fl_ip_sport = inet->sport;
if (!fl.oif && (addr_type&IPV6_ADDR_MULTICAST))
fl.oif = np->mcast_oif;
security_sk_classify_flow(sk, &fl);
if (flowlabel) {
if (flowlabel->opt && flowlabel->opt->srcrt) {
struct rt0_hdr *rt0 = (struct rt0_hdr *) flowlabel->opt->srcrt;
ipv6_addr_copy(&final, &fl.fl6_dst);
ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
final_p = &final;
}
} else if (np->opt && np->opt->srcrt) {
struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
ipv6_addr_copy(&final, &fl.fl6_dst);
ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
final_p = &final;
}
err = ip6_dst_lookup(sk, &dst, &fl);
if (err)
goto out;
if (final_p)
ipv6_addr_copy(&fl.fl6_dst, final_p);
if ((err = __xfrm_lookup(&dst, &fl, sk, XFRM_LOOKUP_WAIT)) < 0) {
if (err == -EREMOTE)
err = ip6_dst_blackhole(sk, &dst, &fl);
if (err < 0)
goto out;
}
/* source address lookup done in ip6_dst_lookup */
if (ipv6_addr_any(&np->saddr))
ipv6_addr_copy(&np->saddr, &fl.fl6_src);
if (ipv6_addr_any(&np->rcv_saddr)) {
ipv6_addr_copy(&np->rcv_saddr, &fl.fl6_src);
inet->rcv_saddr = LOOPBACK4_IPV6;
}
ip6_dst_store(sk, dst,
ipv6_addr_equal(&fl.fl6_dst, &np->daddr) ?
&np->daddr : NULL,
#ifdef CONFIG_IPV6_SUBTREES
ipv6_addr_equal(&fl.fl6_src, &np->saddr) ?
&np->saddr :
#endif
NULL);
sk->sk_state = TCP_ESTABLISHED;
out:
fl6_sock_release(flowlabel);
return err;
}
void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
__be16 port, u32 info, u8 *payload)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct icmp6hdr *icmph = icmp6_hdr(skb);
struct sock_exterr_skb *serr;
if (!np->recverr)
return;
skb = skb_clone(skb, GFP_ATOMIC);
if (!skb)
return;
serr = SKB_EXT_ERR(skb);
serr->ee.ee_errno = err;
serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
serr->ee.ee_type = icmph->icmp6_type;
serr->ee.ee_code = icmph->icmp6_code;
serr->ee.ee_pad = 0;
serr->ee.ee_info = info;
serr->ee.ee_data = 0;
serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
skb_network_header(skb);
serr->port = port;
__skb_pull(skb, payload - skb->data);
skb_reset_transport_header(skb);
if (sock_queue_err_skb(sk, skb))
kfree_skb(skb);
}
void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sock_exterr_skb *serr;
struct ipv6hdr *iph;
struct sk_buff *skb;
if (!np->recverr)
return;
skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
if (!skb)
return;
skb_put(skb, sizeof(struct ipv6hdr));
skb_reset_network_header(skb);
iph = ipv6_hdr(skb);
ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
serr = SKB_EXT_ERR(skb);
serr->ee.ee_errno = err;
serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
serr->ee.ee_type = 0;
serr->ee.ee_code = 0;
serr->ee.ee_pad = 0;
serr->ee.ee_info = info;
serr->ee.ee_data = 0;
serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
serr->port = fl->fl_ip_dport;
__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
skb_reset_transport_header(skb);
if (sock_queue_err_skb(sk, skb))
kfree_skb(skb);
}
/*
* Handle MSG_ERRQUEUE
*/
int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sock_exterr_skb *serr;
struct sk_buff *skb, *skb2;
struct sockaddr_in6 *sin;
struct {
struct sock_extended_err ee;
struct sockaddr_in6 offender;
} errhdr;
int err;
int copied;
err = -EAGAIN;
skb = skb_dequeue(&sk->sk_error_queue);
if (skb == NULL)
goto out;
copied = skb->len;
if (copied > len) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
if (err)
goto out_free_skb;
sock_recv_timestamp(msg, sk, skb);
serr = SKB_EXT_ERR(skb);
sin = (struct sockaddr_in6 *)msg->msg_name;
if (sin) {
const unsigned char *nh = skb_network_header(skb);
sin->sin6_family = AF_INET6;
sin->sin6_flowinfo = 0;
sin->sin6_port = serr->port;
sin->sin6_scope_id = 0;
if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
ipv6_addr_copy(&sin->sin6_addr,
(struct in6_addr *)(nh + serr->addr_offset));
if (np->sndflow)
sin->sin6_flowinfo =
(*(__be32 *)(nh + serr->addr_offset - 24) &
IPV6_FLOWINFO_MASK);
if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
sin->sin6_scope_id = IP6CB(skb)->iif;
} else {
ipv6_addr_set(&sin->sin6_addr, 0, 0,
htonl(0xffff),
*(__be32 *)(nh + serr->addr_offset));
}
}
memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
sin = &errhdr.offender;
sin->sin6_family = AF_UNSPEC;
if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {
sin->sin6_family = AF_INET6;
sin->sin6_flowinfo = 0;
sin->sin6_scope_id = 0;
if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
ipv6_addr_copy(&sin->sin6_addr, &ipv6_hdr(skb)->saddr);
if (np->rxopt.all)
datagram_recv_ctl(sk, msg, skb);
if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
sin->sin6_scope_id = IP6CB(skb)->iif;
} else {
struct inet_sock *inet = inet_sk(sk);
ipv6_addr_set(&sin->sin6_addr, 0, 0,
htonl(0xffff), ip_hdr(skb)->saddr);
if (inet->cmsg_flags)
ip_cmsg_recv(msg, skb);
}
}
put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
/* Now we could try to dump offended packet options */
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
/* Reset and regenerate socket error */
spin_lock_bh(&sk->sk_error_queue.lock);
sk->sk_err = 0;
if ((skb2 = skb_peek(&sk->sk_error_queue)) != NULL) {
sk->sk_err = SKB_EXT_ERR(skb2)->ee.ee_errno;
spin_unlock_bh(&sk->sk_error_queue.lock);
sk->sk_error_report(sk);
} else {
spin_unlock_bh(&sk->sk_error_queue.lock);
}
out_free_skb:
kfree_skb(skb);
out:
return err;
}
int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct inet6_skb_parm *opt = IP6CB(skb);
unsigned char *nh = skb_network_header(skb);
if (np->rxopt.bits.rxinfo) {
struct in6_pktinfo src_info;
src_info.ipi6_ifindex = opt->iif;
ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO, sizeof(src_info), &src_info);
}
if (np->rxopt.bits.rxhlim) {
int hlim = ipv6_hdr(skb)->hop_limit;
put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
}
if (np->rxopt.bits.rxtclass) {
int tclass = (ntohl(*(__be32 *)ipv6_hdr(skb)) >> 20) & 0xff;
put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
}
if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
__be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
}
/* HbH is allowed only once */
if (np->rxopt.bits.hopopts && opt->hop) {
u8 *ptr = nh + opt->hop;
put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
}
if (opt->lastopt &&
(np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
/*
* Silly enough, but we need to reparse in order to
* report extension headers (except for HbH)
* in order.
*
* Also note that IPV6_RECVRTHDRDSTOPTS is NOT
* (and WILL NOT be) defined because
* IPV6_RECVDSTOPTS is more generic. --yoshfuji
*/
unsigned int off = sizeof(struct ipv6hdr);
u8 nexthdr = ipv6_hdr(skb)->nexthdr;
while (off <= opt->lastopt) {
unsigned len;
u8 *ptr = nh + off;
switch(nexthdr) {
case IPPROTO_DSTOPTS:
nexthdr = ptr[0];
len = (ptr[1] + 1) << 3;
if (np->rxopt.bits.dstopts)
put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
break;
case IPPROTO_ROUTING:
nexthdr = ptr[0];
len = (ptr[1] + 1) << 3;
if (np->rxopt.bits.srcrt)
put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
break;
case IPPROTO_AH:
nexthdr = ptr[0];
len = (ptr[1] + 2) << 2;
break;
default:
nexthdr = ptr[0];
len = (ptr[1] + 1) << 3;
break;
}
off += len;
}
}
/* socket options in old style */
if (np->rxopt.bits.rxoinfo) {
struct in6_pktinfo src_info;
src_info.ipi6_ifindex = opt->iif;
ipv6_addr_copy(&src_info.ipi6_addr, &ipv6_hdr(skb)->daddr);
put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
}
if (np->rxopt.bits.rxohlim) {
int hlim = ipv6_hdr(skb)->hop_limit;
put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
}
if (np->rxopt.bits.ohopopts && opt->hop) {
u8 *ptr = nh + opt->hop;
put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
}
if (np->rxopt.bits.odstopts && opt->dst0) {
u8 *ptr = nh + opt->dst0;
put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
}
if (np->rxopt.bits.osrcrt && opt->srcrt) {
struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
}
if (np->rxopt.bits.odstopts && opt->dst1) {
u8 *ptr = nh + opt->dst1;
put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
}
return 0;
}
int datagram_send_ctl(struct msghdr *msg, struct flowi *fl,
struct ipv6_txoptions *opt,
int *hlimit, int *tclass)
{
struct in6_pktinfo *src_info;
struct cmsghdr *cmsg;
struct ipv6_rt_hdr *rthdr;
struct ipv6_opt_hdr *hdr;
int len;
int err = 0;
for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
int addr_type;
struct net_device *dev = NULL;
if (!CMSG_OK(msg, cmsg)) {
err = -EINVAL;
goto exit_f;
}
if (cmsg->cmsg_level != SOL_IPV6)
continue;
switch (cmsg->cmsg_type) {
case IPV6_PKTINFO:
case IPV6_2292PKTINFO:
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
err = -EINVAL;
goto exit_f;
}
src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
if (src_info->ipi6_ifindex) {
if (fl->oif && src_info->ipi6_ifindex != fl->oif)
return -EINVAL;
fl->oif = src_info->ipi6_ifindex;
}
addr_type = ipv6_addr_type(&src_info->ipi6_addr);
if (addr_type == IPV6_ADDR_ANY)
break;
if (addr_type & IPV6_ADDR_LINKLOCAL) {
if (!src_info->ipi6_ifindex)
return -EINVAL;
else {
dev = dev_get_by_index(&init_net, src_info->ipi6_ifindex);
if (!dev)
return -ENODEV;
}
}
if (!ipv6_chk_addr(&init_net, &src_info->ipi6_addr,
dev, 0)) {
if (dev)
dev_put(dev);
err = -EINVAL;
goto exit_f;
}
if (dev)
dev_put(dev);
ipv6_addr_copy(&fl->fl6_src, &src_info->ipi6_addr);
break;
case IPV6_FLOWINFO:
if (cmsg->cmsg_len < CMSG_LEN(4)) {
err = -EINVAL;
goto exit_f;
}
if (fl->fl6_flowlabel&IPV6_FLOWINFO_MASK) {
if ((fl->fl6_flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
err = -EINVAL;
goto exit_f;
}
}
fl->fl6_flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
break;
case IPV6_2292HOPOPTS:
case IPV6_HOPOPTS:
if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
err = -EINVAL;
goto exit_f;
}
hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
len = ((hdr->hdrlen + 1) << 3);
if (cmsg->cmsg_len < CMSG_LEN(len)) {
err = -EINVAL;
goto exit_f;
}
if (!capable(CAP_NET_RAW)) {
err = -EPERM;
goto exit_f;
}
opt->opt_nflen += len;
opt->hopopt = hdr;
break;
case IPV6_2292DSTOPTS:
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
err = -EINVAL;
goto exit_f;
}
hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
len = ((hdr->hdrlen + 1) << 3);
if (cmsg->cmsg_len < CMSG_LEN(len)) {
err = -EINVAL;
goto exit_f;
}
if (!capable(CAP_NET_RAW)) {
err = -EPERM;
goto exit_f;
}
if (opt->dst1opt) {
err = -EINVAL;
goto exit_f;
}
opt->opt_flen += len;
opt->dst1opt = hdr;
break;
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
err = -EINVAL;
goto exit_f;
}
hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
len = ((hdr->hdrlen + 1) << 3);
if (cmsg->cmsg_len < CMSG_LEN(len)) {
err = -EINVAL;
goto exit_f;
}
if (!capable(CAP_NET_RAW)) {
err = -EPERM;
goto exit_f;
}
if (cmsg->cmsg_type == IPV6_DSTOPTS) {
opt->opt_flen += len;
opt->dst1opt = hdr;
} else {
opt->opt_nflen += len;
opt->dst0opt = hdr;
}
break;
case IPV6_2292RTHDR:
case IPV6_RTHDR:
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
err = -EINVAL;
goto exit_f;
}
rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
switch (rthdr->type) {
#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
case IPV6_SRCRT_TYPE_2:
break;
#endif
default:
err = -EINVAL;
goto exit_f;
}
len = ((rthdr->hdrlen + 1) << 3);
if (cmsg->cmsg_len < CMSG_LEN(len)) {
err = -EINVAL;
goto exit_f;
}
/* segments left must also match */
if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
err = -EINVAL;
goto exit_f;
}
opt->opt_nflen += len;
opt->srcrt = rthdr;
if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
opt->opt_nflen += dsthdrlen;
opt->dst0opt = opt->dst1opt;
opt->dst1opt = NULL;
opt->opt_flen -= dsthdrlen;
}
break;
case IPV6_2292HOPLIMIT:
case IPV6_HOPLIMIT:
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
err = -EINVAL;
goto exit_f;
}
*hlimit = *(int *)CMSG_DATA(cmsg);
break;
case IPV6_TCLASS:
{
int tc;
err = -EINVAL;
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
goto exit_f;
}
tc = *(int *)CMSG_DATA(cmsg);
if (tc < -1 || tc > 0xff)
goto exit_f;
err = 0;
*tclass = tc;
break;
}
default:
LIMIT_NETDEBUG(KERN_DEBUG "invalid cmsg type: %d\n",
cmsg->cmsg_type);
err = -EINVAL;
break;
}
}
exit_f:
return err;
}
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