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authorArnaldo Carvalho de Melo <acme@mandriva.com>2005-12-13 23:25:44 -0800
committerDavid S. Miller <davem@sunset.davemloft.net>2006-01-03 13:10:56 -0800
commitd8313f5ca2b1f86b7df6c99fc4b3fffa1f84e92b (patch)
tree1ee41d265c7790e4389bf4d123b2b60975ad2967
parenta7f5e7f164788a22eb5d3de8e2d3cee1bf58fdca (diff)
downloadtalos-obmc-linux-d8313f5ca2b1f86b7df6c99fc4b3fffa1f84e92b.tar.gz
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[INET6]: Generalise tcp_v6_hash_connect
Renaming it to inet6_hash_connect, making it possible to ditch dccp_v6_hash_connect and share the same code with TCP instead. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/char/random.c4
-rw-r--r--include/linux/random.h4
-rw-r--r--include/net/ipv6.h3
-rw-r--r--net/dccp/ipv6.c171
-rw-r--r--net/ipv6/inet6_hashtables.c183
-rw-r--r--net/ipv6/tcp_ipv6.c173
6 files changed, 190 insertions, 348 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 79b59d986af4..bdfdfd28594d 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1573,7 +1573,7 @@ u32 secure_ipv4_port_ephemeral(__u32 saddr, __u32 daddr, __u16 dport)
}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-u32 secure_tcpv6_port_ephemeral(const __u32 *saddr, const __u32 *daddr, __u16 dport)
+u32 secure_ipv6_port_ephemeral(const __u32 *saddr, const __u32 *daddr, __u16 dport)
{
struct keydata *keyptr = get_keyptr();
u32 hash[12];
@@ -1584,7 +1584,7 @@ u32 secure_tcpv6_port_ephemeral(const __u32 *saddr, const __u32 *daddr, __u16 dp
return twothirdsMD4Transform(daddr, hash);
}
-EXPORT_SYMBOL(secure_tcpv6_port_ephemeral);
+EXPORT_SYMBOL(secure_ipv6_port_ephemeral);
#endif
#if defined(CONFIG_IP_DCCP) || defined(CONFIG_IP_DCCP_MODULE)
diff --git a/include/linux/random.h b/include/linux/random.h
index 01424a8e621c..5d6456bcdeba 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -53,8 +53,8 @@ void generate_random_uuid(unsigned char uuid_out[16]);
extern __u32 secure_ip_id(__u32 daddr);
extern u32 secure_ipv4_port_ephemeral(__u32 saddr, __u32 daddr, __u16 dport);
-extern u32 secure_tcpv6_port_ephemeral(const __u32 *saddr, const __u32 *daddr,
- __u16 dport);
+extern u32 secure_ipv6_port_ephemeral(const __u32 *saddr, const __u32 *daddr,
+ __u16 dport);
extern __u32 secure_tcp_sequence_number(__u32 saddr, __u32 daddr,
__u16 sport, __u16 dport);
extern __u32 secure_tcpv6_sequence_number(__u32 *saddr, __u32 *daddr,
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 851376108ac2..e3d5d7bc8837 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -527,6 +527,9 @@ extern int inet6_getname(struct socket *sock, struct sockaddr *uaddr,
extern int inet6_ioctl(struct socket *sock, unsigned int cmd,
unsigned long arg);
+extern int inet6_hash_connect(struct inet_timewait_death_row *death_row,
+ struct sock *sk);
+
/*
* reassembly.c
*/
diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 4d078f5b911b..71bf04eb21e1 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -84,175 +84,6 @@ static __u32 dccp_v6_init_sequence(struct sock *sk, struct sk_buff *skb)
dh->dccph_sport);
}
-static int __dccp_v6_check_established(struct sock *sk, const __u16 lport,
- struct inet_timewait_sock **twp)
-{
- struct inet_sock *inet = inet_sk(sk);
- const struct ipv6_pinfo *np = inet6_sk(sk);
- const struct in6_addr *daddr = &np->rcv_saddr;
- const struct in6_addr *saddr = &np->daddr;
- const int dif = sk->sk_bound_dev_if;
- const u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
- const unsigned int hash = inet6_ehashfn(daddr, inet->num,
- saddr, inet->dport);
- struct inet_ehash_bucket *head = inet_ehash_bucket(&dccp_hashinfo, hash);
- struct sock *sk2;
- const struct hlist_node *node;
- struct inet_timewait_sock *tw;
-
- prefetch(head->chain.first);
- write_lock(&head->lock);
-
- /* Check TIME-WAIT sockets first. */
- sk_for_each(sk2, node, &(head + dccp_hashinfo.ehash_size)->chain) {
- const struct inet6_timewait_sock *tw6 = inet6_twsk(sk2);
-
- tw = inet_twsk(sk2);
-
- if(*((__u32 *)&(tw->tw_dport)) == ports &&
- sk2->sk_family == PF_INET6 &&
- ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) &&
- ipv6_addr_equal(&tw6->tw_v6_rcv_saddr, daddr) &&
- sk2->sk_bound_dev_if == sk->sk_bound_dev_if)
- goto not_unique;
- }
- tw = NULL;
-
- /* And established part... */
- sk_for_each(sk2, node, &head->chain) {
- if (INET6_MATCH(sk2, hash, saddr, daddr, ports, dif))
- goto not_unique;
- }
-
- BUG_TRAP(sk_unhashed(sk));
- __sk_add_node(sk, &head->chain);
- sk->sk_hash = hash;
- sock_prot_inc_use(sk->sk_prot);
- write_unlock(&head->lock);
-
- if (twp) {
- *twp = tw;
- NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
- } else if (tw) {
- /* Silly. Should hash-dance instead... */
- inet_twsk_deschedule(tw, &dccp_death_row);
- NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
-
- inet_twsk_put(tw);
- }
- return 0;
-
-not_unique:
- write_unlock(&head->lock);
- return -EADDRNOTAVAIL;
-}
-
-static inline u32 dccp_v6_port_offset(const struct sock *sk)
-{
- const struct inet_sock *inet = inet_sk(sk);
- const struct ipv6_pinfo *np = inet6_sk(sk);
-
- return secure_tcpv6_port_ephemeral(np->rcv_saddr.s6_addr32,
- np->daddr.s6_addr32,
- inet->dport);
-}
-
-static int dccp_v6_hash_connect(struct sock *sk)
-{
- const unsigned short snum = inet_sk(sk)->num;
- struct inet_bind_hashbucket *head;
- struct inet_bind_bucket *tb;
- int ret;
-
- if (snum == 0) {
- int low = sysctl_local_port_range[0];
- int high = sysctl_local_port_range[1];
- int range = high - low;
- int i;
- int port;
- static u32 hint;
- u32 offset = hint + dccp_v6_port_offset(sk);
- struct hlist_node *node;
- struct inet_timewait_sock *tw = NULL;
-
- local_bh_disable();
- for (i = 1; i <= range; i++) {
- port = low + (i + offset) % range;
- head = &dccp_hashinfo.bhash[inet_bhashfn(port,
- dccp_hashinfo.bhash_size)];
- spin_lock(&head->lock);
-
- /* Does not bother with rcv_saddr checks,
- * because the established check is already
- * unique enough.
- */
- inet_bind_bucket_for_each(tb, node, &head->chain) {
- if (tb->port == port) {
- BUG_TRAP(!hlist_empty(&tb->owners));
- if (tb->fastreuse >= 0)
- goto next_port;
- if (!__dccp_v6_check_established(sk,
- port,
- &tw))
- goto ok;
- goto next_port;
- }
- }
-
- tb = inet_bind_bucket_create(dccp_hashinfo.bind_bucket_cachep,
- head, port);
- if (!tb) {
- spin_unlock(&head->lock);
- break;
- }
- tb->fastreuse = -1;
- goto ok;
-
- next_port:
- spin_unlock(&head->lock);
- }
- local_bh_enable();
-
- return -EADDRNOTAVAIL;
-ok:
- hint += i;
-
- /* Head lock still held and bh's disabled */
- inet_bind_hash(sk, tb, port);
- if (sk_unhashed(sk)) {
- inet_sk(sk)->sport = htons(port);
- __inet6_hash(&dccp_hashinfo, sk);
- }
- spin_unlock(&head->lock);
-
- if (tw) {
- inet_twsk_deschedule(tw, &dccp_death_row);
- inet_twsk_put(tw);
- }
-
- ret = 0;
- goto out;
- }
-
- head = &dccp_hashinfo.bhash[inet_bhashfn(snum,
- dccp_hashinfo.bhash_size)];
- tb = inet_csk(sk)->icsk_bind_hash;
- spin_lock_bh(&head->lock);
-
- if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
- __inet6_hash(&dccp_hashinfo, sk);
- spin_unlock_bh(&head->lock);
- return 0;
- } else {
- spin_unlock(&head->lock);
- /* No definite answer... Walk to established hash table */
- ret = __dccp_v6_check_established(sk, snum, NULL);
-out:
- local_bh_enable();
- return ret;
- }
-}
-
static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
int addr_len)
{
@@ -403,7 +234,7 @@ static int dccp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
inet->dport = usin->sin6_port;
dccp_set_state(sk, DCCP_REQUESTING);
- err = dccp_v6_hash_connect(sk);
+ err = inet6_hash_connect(&dccp_death_row, sk);
if (err)
goto late_failure;
/* FIXME */
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 01d5f46d4e40..4154f3a8b6cf 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -5,7 +5,8 @@
*
* Generic INET6 transport hashtables
*
- * Authors: Lotsa people, from code originally in tcp
+ * Authors: Lotsa people, from code originally in tcp, generalised here
+ * by Arnaldo Carvalho de Melo <acme@mandriva.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
@@ -14,12 +15,13 @@
*/
#include <linux/config.h>
-
#include <linux/module.h>
+#include <linux/random.h>
#include <net/inet_connection_sock.h>
#include <net/inet_hashtables.h>
#include <net/inet6_hashtables.h>
+#include <net/ip.h>
struct sock *inet6_lookup_listener(struct inet_hashinfo *hashinfo,
const struct in6_addr *daddr,
@@ -79,3 +81,180 @@ struct sock *inet6_lookup(struct inet_hashinfo *hashinfo,
}
EXPORT_SYMBOL_GPL(inet6_lookup);
+
+static int __inet6_check_established(struct inet_timewait_death_row *death_row,
+ struct sock *sk, const __u16 lport,
+ struct inet_timewait_sock **twp)
+{
+ struct inet_hashinfo *hinfo = death_row->hashinfo;
+ const struct inet_sock *inet = inet_sk(sk);
+ const struct ipv6_pinfo *np = inet6_sk(sk);
+ const struct in6_addr *daddr = &np->rcv_saddr;
+ const struct in6_addr *saddr = &np->daddr;
+ const int dif = sk->sk_bound_dev_if;
+ const u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
+ const unsigned int hash = inet6_ehashfn(daddr, inet->num, saddr,
+ inet->dport);
+ struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
+ struct sock *sk2;
+ const struct hlist_node *node;
+ struct inet_timewait_sock *tw;
+
+ prefetch(head->chain.first);
+ write_lock(&head->lock);
+
+ /* Check TIME-WAIT sockets first. */
+ sk_for_each(sk2, node, &(head + hinfo->ehash_size)->chain) {
+ const struct inet6_timewait_sock *tw6 = inet6_twsk(sk2);
+
+ tw = inet_twsk(sk2);
+
+ if(*((__u32 *)&(tw->tw_dport)) == ports &&
+ sk2->sk_family == PF_INET6 &&
+ ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) &&
+ ipv6_addr_equal(&tw6->tw_v6_rcv_saddr, daddr) &&
+ sk2->sk_bound_dev_if == sk->sk_bound_dev_if) {
+ if (twsk_unique(sk, sk2, twp))
+ goto unique;
+ else
+ goto not_unique;
+ }
+ }
+ tw = NULL;
+
+ /* And established part... */
+ sk_for_each(sk2, node, &head->chain) {
+ if (INET6_MATCH(sk2, hash, saddr, daddr, ports, dif))
+ goto not_unique;
+ }
+
+unique:
+ BUG_TRAP(sk_unhashed(sk));
+ __sk_add_node(sk, &head->chain);
+ sk->sk_hash = hash;
+ sock_prot_inc_use(sk->sk_prot);
+ write_unlock(&head->lock);
+
+ if (twp != NULL) {
+ *twp = tw;
+ NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
+ } else if (tw != NULL) {
+ /* Silly. Should hash-dance instead... */
+ inet_twsk_deschedule(tw, death_row);
+ NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
+
+ inet_twsk_put(tw);
+ }
+ return 0;
+
+not_unique:
+ write_unlock(&head->lock);
+ return -EADDRNOTAVAIL;
+}
+
+static inline u32 inet6_sk_port_offset(const struct sock *sk)
+{
+ const struct inet_sock *inet = inet_sk(sk);
+ const struct ipv6_pinfo *np = inet6_sk(sk);
+ return secure_ipv6_port_ephemeral(np->rcv_saddr.s6_addr32,
+ np->daddr.s6_addr32,
+ inet->dport);
+}
+
+int inet6_hash_connect(struct inet_timewait_death_row *death_row,
+ struct sock *sk)
+{
+ struct inet_hashinfo *hinfo = death_row->hashinfo;
+ const unsigned short snum = inet_sk(sk)->num;
+ struct inet_bind_hashbucket *head;
+ struct inet_bind_bucket *tb;
+ int ret;
+
+ if (snum == 0) {
+ const int low = sysctl_local_port_range[0];
+ const int high = sysctl_local_port_range[1];
+ const int range = high - low;
+ int i, port;
+ static u32 hint;
+ const u32 offset = hint + inet6_sk_port_offset(sk);
+ struct hlist_node *node;
+ struct inet_timewait_sock *tw = NULL;
+
+ local_bh_disable();
+ for (i = 1; i <= range; i++) {
+ port = low + (i + offset) % range;
+ head = &hinfo->bhash[inet_bhashfn(port, hinfo->bhash_size)];
+ spin_lock(&head->lock);
+
+ /* Does not bother with rcv_saddr checks,
+ * because the established check is already
+ * unique enough.
+ */
+ inet_bind_bucket_for_each(tb, node, &head->chain) {
+ if (tb->port == port) {
+ BUG_TRAP(!hlist_empty(&tb->owners));
+ if (tb->fastreuse >= 0)
+ goto next_port;
+ if (!__inet6_check_established(death_row,
+ sk, port,
+ &tw))
+ goto ok;
+ goto next_port;
+ }
+ }
+
+ tb = inet_bind_bucket_create(hinfo->bind_bucket_cachep,
+ head, port);
+ if (!tb) {
+ spin_unlock(&head->lock);
+ break;
+ }
+ tb->fastreuse = -1;
+ goto ok;
+
+ next_port:
+ spin_unlock(&head->lock);
+ }
+ local_bh_enable();
+
+ return -EADDRNOTAVAIL;
+
+ok:
+ hint += i;
+
+ /* Head lock still held and bh's disabled */
+ inet_bind_hash(sk, tb, port);
+ if (sk_unhashed(sk)) {
+ inet_sk(sk)->sport = htons(port);
+ __inet6_hash(hinfo, sk);
+ }
+ spin_unlock(&head->lock);
+
+ if (tw) {
+ inet_twsk_deschedule(tw, death_row);
+ inet_twsk_put(tw);
+ }
+
+ ret = 0;
+ goto out;
+ }
+
+ head = &hinfo->bhash[inet_bhashfn(snum, hinfo->bhash_size)];
+ tb = inet_csk(sk)->icsk_bind_hash;
+ spin_lock_bh(&head->lock);
+
+ if (sk_head(&tb->owners) == sk && sk->sk_bind_node.next == NULL) {
+ __inet6_hash(hinfo, sk);
+ spin_unlock_bh(&head->lock);
+ return 0;
+ } else {
+ spin_unlock(&head->lock);
+ /* No definite answer... Walk to established hash table */
+ ret = __inet6_check_established(death_row, sk, snum, NULL);
+out:
+ local_bh_enable();
+ return ret;
+ }
+}
+
+EXPORT_SYMBOL_GPL(inet6_hash_connect);
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 514b57bb80b7..a682eb9093e1 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -119,177 +119,6 @@ static __u32 tcp_v6_init_sequence(struct sock *sk, struct sk_buff *skb)
}
}
-static int __tcp_v6_check_established(struct sock *sk, const __u16 lport,
- struct inet_timewait_sock **twp)
-{
- struct inet_sock *inet = inet_sk(sk);
- const struct ipv6_pinfo *np = inet6_sk(sk);
- const struct in6_addr *daddr = &np->rcv_saddr;
- const struct in6_addr *saddr = &np->daddr;
- const int dif = sk->sk_bound_dev_if;
- const u32 ports = INET_COMBINED_PORTS(inet->dport, lport);
- unsigned int hash = inet6_ehashfn(daddr, inet->num, saddr, inet->dport);
- struct inet_ehash_bucket *head = inet_ehash_bucket(&tcp_hashinfo, hash);
- struct sock *sk2;
- const struct hlist_node *node;
- struct inet_timewait_sock *tw;
-
- prefetch(head->chain.first);
- write_lock(&head->lock);
-
- /* Check TIME-WAIT sockets first. */
- sk_for_each(sk2, node, &(head + tcp_hashinfo.ehash_size)->chain) {
- const struct inet6_timewait_sock *tw6 = inet6_twsk(sk2);
-
- tw = inet_twsk(sk2);
-
- if(*((__u32 *)&(tw->tw_dport)) == ports &&
- sk2->sk_family == PF_INET6 &&
- ipv6_addr_equal(&tw6->tw_v6_daddr, saddr) &&
- ipv6_addr_equal(&tw6->tw_v6_rcv_saddr, daddr) &&
- sk2->sk_bound_dev_if == sk->sk_bound_dev_if) {
- if (twsk_unique(sk, sk2, twp))
- goto unique;
- else
- goto not_unique;
- }
- }
- tw = NULL;
-
- /* And established part... */
- sk_for_each(sk2, node, &head->chain) {
- if (INET6_MATCH(sk2, hash, saddr, daddr, ports, dif))
- goto not_unique;
- }
-
-unique:
- BUG_TRAP(sk_unhashed(sk));
- __sk_add_node(sk, &head->chain);
- sk->sk_hash = hash;
- sock_prot_inc_use(sk->sk_prot);
- write_unlock(&head->lock);
-
- if (twp) {
- *twp = tw;
- NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
- } else if (tw) {
- /* Silly. Should hash-dance instead... */
- inet_twsk_deschedule(tw, &tcp_death_row);
- NET_INC_STATS_BH(LINUX_MIB_TIMEWAITRECYCLED);
-
- inet_twsk_put(tw);
- }
- return 0;
-
-not_unique:
- write_unlock(&head->lock);
- return -EADDRNOTAVAIL;
-}
-
-static inline u32 tcpv6_port_offset(const struct sock *sk)
-{
- const struct inet_sock *inet = inet_sk(sk);
- const struct ipv6_pinfo *np = inet6_sk(sk);
-
- return secure_tcpv6_port_ephemeral(np->rcv_saddr.s6_addr32,
- np->daddr.s6_addr32,
- inet->dport);
-}
-
-static int tcp_v6_hash_connect(struct sock *sk)
-{
- unsigned short snum = inet_sk(sk)->num;
- struct inet_bind_hashbucket *head;
- struct inet_bind_bucket *tb;
- int ret;
-
- if (!snum) {
- int low = sysctl_local_port_range[0];
- int high = sysctl_local_port_range[1];
- int range = high - low;
- int i;
- int port;
- static u32 hint;
- u32 offset = hint + tcpv6_port_offset(sk);
- struct hlist_node *node;
- struct inet_timewait_sock *tw = NULL;
-
- local_bh_disable();
- for (i = 1; i <= range; i++) {
- port = low + (i + offset) % range;
- head = &tcp_hashinfo.bhash[inet_bhashfn(port, tcp_hashinfo.bhash_size)];
- spin_lock(&head->lock);
-
- /* Does not bother with rcv_saddr checks,
- * because the established check is already
- * unique enough.
- */
- inet_bind_bucket_for_each(tb, node, &head->chain) {
- if (tb->port == port) {
- BUG_TRAP(!hlist_empty(&tb->owners));
- if (tb->fastreuse >= 0)
- goto next_port;
- if (!__tcp_v6_check_established(sk,
- port,
- &tw))
- goto ok;
- goto next_port;
- }
- }
-
- tb = inet_bind_bucket_create(tcp_hashinfo.bind_bucket_cachep, head, port);
- if (!tb) {
- spin_unlock(&head->lock);
- break;
- }
- tb->fastreuse = -1;
- goto ok;
-
- next_port:
- spin_unlock(&head->lock);
- }
- local_bh_enable();
-
- return -EADDRNOTAVAIL;
-
-ok:
- hint += i;
-
- /* Head lock still held and bh's disabled */
- inet_bind_hash(sk, tb, port);
- if (sk_unhashed(sk)) {
- inet_sk(sk)->sport = htons(port);
- __inet6_hash(&tcp_hashinfo, sk);
- }
- spin_unlock(&head->lock);
-
- if (tw) {
- inet_twsk_deschedule(tw, &tcp_death_row);
- inet_twsk_put(tw);
- }
-
- ret = 0;
- goto out;
- }
-
- head = &tcp_hashinfo.bhash[inet_bhashfn(snum, tcp_hashinfo.bhash_size)];
- tb = inet_csk(sk)->icsk_bind_hash;
- spin_lock_bh(&head->lock);
-
- if (sk_head(&tb->owners) == sk && !sk->sk_bind_node.next) {
- __inet6_hash(&tcp_hashinfo, sk);
- spin_unlock_bh(&head->lock);
- return 0;
- } else {
- spin_unlock(&head->lock);
- /* No definite answer... Walk to established hash table */
- ret = __tcp_v6_check_established(sk, snum, NULL);
-out:
- local_bh_enable();
- return ret;
- }
-}
-
static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
int addr_len)
{
@@ -450,7 +279,7 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
inet->dport = usin->sin6_port;
tcp_set_state(sk, TCP_SYN_SENT);
- err = tcp_v6_hash_connect(sk);
+ err = inet6_hash_connect(&tcp_death_row, sk);
if (err)
goto late_failure;
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