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authorLinus Torvalds <torvalds@linux-foundation.org>2018-04-06 15:39:26 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-04-06 15:39:26 -0700
commit9eda2d2dca830f0f8923b1f377d0fb70f576af1d (patch)
tree5bdc06d14182e67ebdf20e5543de2a407563662f /net/sctp
parent6ad11bdd57ad31182850a54235f0e947cbfd5ad0 (diff)
parent6b6bc6205d98796361962ee282a063f18ba8dc57 (diff)
Merge tag 'selinux-pr-20180403' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull SELinux updates from Paul Moore: "A bigger than usual pull request for SELinux, 13 patches (lucky!) along with a scary looking diffstat. Although if you look a bit closer, excluding the usual minor tweaks/fixes, there are really only two significant changes in this pull request: the addition of proper SELinux access controls for SCTP and the encapsulation of a lot of internal SELinux state. The SCTP changes are the result of a multi-month effort (maybe even a year or longer?) between the SELinux folks and the SCTP folks to add proper SELinux controls. A special thanks go to Richard for seeing this through and keeping the effort moving forward. The state encapsulation work is a bit of janitorial work that came out of some early work on SELinux namespacing. The question of namespacing is still an open one, but I believe there is some real value in the encapsulation work so we've split that out and are now sending that up to you" * tag 'selinux-pr-20180403' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: selinux: wrap AVC state selinux: wrap selinuxfs state selinux: fix handling of uninitialized selinux state in get_bools/classes selinux: Update SELinux SCTP documentation selinux: Fix ltp test connect-syscall failure selinux: rename the {is,set}_enforcing() functions selinux: wrap global selinux state selinux: fix typo in selinux_netlbl_sctp_sk_clone declaration selinux: Add SCTP support sctp: Add LSM hooks sctp: Add ip option support security: Add support for SCTP security hooks netlabel: If PF_INET6, check sk_buff ip header version
Diffstat (limited to 'net/sctp')
-rw-r--r--net/sctp/chunk.c10
-rw-r--r--net/sctp/ipv6.c45
-rw-r--r--net/sctp/output.c34
-rw-r--r--net/sctp/protocol.c43
-rw-r--r--net/sctp/sm_make_chunk.c12
-rw-r--r--net/sctp/sm_statefuns.c18
-rw-r--r--net/sctp/socket.c70
7 files changed, 205 insertions, 27 deletions
diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
index f889a84f264d..be296d633e95 100644
--- a/net/sctp/chunk.c
+++ b/net/sctp/chunk.c
@@ -172,6 +172,8 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
struct list_head *pos, *temp;
struct sctp_chunk *chunk;
struct sctp_datamsg *msg;
+ struct sctp_sock *sp;
+ struct sctp_af *af;
int err;
msg = sctp_datamsg_new(GFP_KERNEL);
@@ -190,9 +192,11 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
/* This is the biggest possible DATA chunk that can fit into
* the packet
*/
- max_data = asoc->pathmtu -
- sctp_sk(asoc->base.sk)->pf->af->net_header_len -
- sizeof(struct sctphdr) - sctp_datachk_len(&asoc->stream);
+ sp = sctp_sk(asoc->base.sk);
+ af = sp->pf->af;
+ max_data = asoc->pathmtu - af->net_header_len -
+ sizeof(struct sctphdr) - sctp_datachk_len(&asoc->stream) -
+ af->ip_options_len(asoc->base.sk);
max_data = SCTP_TRUNC4(max_data);
/* If the the peer requested that we authenticate DATA chunks
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index 0d873c58e516..6dd976c8ab61 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -427,6 +427,41 @@ static void sctp_v6_copy_addrlist(struct list_head *addrlist,
rcu_read_unlock();
}
+/* Copy over any ip options */
+static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk)
+{
+ struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
+ struct ipv6_txoptions *opt;
+
+ newnp = inet6_sk(newsk);
+
+ rcu_read_lock();
+ opt = rcu_dereference(np->opt);
+ if (opt) {
+ opt = ipv6_dup_options(newsk, opt);
+ if (!opt)
+ pr_err("%s: Failed to copy ip options\n", __func__);
+ }
+ RCU_INIT_POINTER(newnp->opt, opt);
+ rcu_read_unlock();
+}
+
+/* Account for the IP options */
+static int sctp_v6_ip_options_len(struct sock *sk)
+{
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct ipv6_txoptions *opt;
+ int len = 0;
+
+ rcu_read_lock();
+ opt = rcu_dereference(np->opt);
+ if (opt)
+ len = opt->opt_flen + opt->opt_nflen;
+
+ rcu_read_unlock();
+ return len;
+}
+
/* Initialize a sockaddr_storage from in incoming skb. */
static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb,
int is_saddr)
@@ -666,7 +701,6 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
struct sock *newsk;
struct ipv6_pinfo *newnp, *np = inet6_sk(sk);
struct sctp6_sock *newsctp6sk;
- struct ipv6_txoptions *opt;
newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern);
if (!newsk)
@@ -689,12 +723,7 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk,
newnp->ipv6_ac_list = NULL;
newnp->ipv6_fl_list = NULL;
- rcu_read_lock();
- opt = rcu_dereference(np->opt);
- if (opt)
- opt = ipv6_dup_options(newsk, opt);
- RCU_INIT_POINTER(newnp->opt, opt);
- rcu_read_unlock();
+ sctp_v6_copy_ip_options(sk, newsk);
/* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname()
* and getpeername().
@@ -1041,6 +1070,7 @@ static struct sctp_af sctp_af_inet6 = {
.ecn_capable = sctp_v6_ecn_capable,
.net_header_len = sizeof(struct ipv6hdr),
.sockaddr_len = sizeof(struct sockaddr_in6),
+ .ip_options_len = sctp_v6_ip_options_len,
#ifdef CONFIG_COMPAT
.compat_setsockopt = compat_ipv6_setsockopt,
.compat_getsockopt = compat_ipv6_getsockopt,
@@ -1059,6 +1089,7 @@ static struct sctp_pf sctp_pf_inet6 = {
.addr_to_user = sctp_v6_addr_to_user,
.to_sk_saddr = sctp_v6_to_sk_saddr,
.to_sk_daddr = sctp_v6_to_sk_daddr,
+ .copy_ip_options = sctp_v6_copy_ip_options,
.af = &sctp_af_inet6,
};
diff --git a/net/sctp/output.c b/net/sctp/output.c
index d6e1c90cc09a..690d8557bb7b 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -69,7 +69,11 @@ static enum sctp_xmit sctp_packet_will_fit(struct sctp_packet *packet,
static void sctp_packet_reset(struct sctp_packet *packet)
{
+ /* sctp_packet_transmit() relies on this to reset size to the
+ * current overhead after sending packets.
+ */
packet->size = packet->overhead;
+
packet->has_cookie_echo = 0;
packet->has_sack = 0;
packet->has_data = 0;
@@ -87,6 +91,7 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag,
struct sctp_transport *tp = packet->transport;
struct sctp_association *asoc = tp->asoc;
struct sock *sk;
+ size_t overhead = sizeof(struct ipv6hdr) + sizeof(struct sctphdr);
pr_debug("%s: packet:%p vtag:0x%x\n", __func__, packet, vtag);
packet->vtag = vtag;
@@ -95,10 +100,22 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag,
if (!sctp_packet_empty(packet))
return;
- /* set packet max_size with pathmtu */
+ /* set packet max_size with pathmtu, then calculate overhead */
packet->max_size = tp->pathmtu;
- if (!asoc)
+ if (asoc) {
+ struct sctp_sock *sp = sctp_sk(asoc->base.sk);
+ struct sctp_af *af = sp->pf->af;
+
+ overhead = af->net_header_len +
+ af->ip_options_len(asoc->base.sk);
+ overhead += sizeof(struct sctphdr);
+ packet->overhead = overhead;
+ packet->size = overhead;
+ } else {
+ packet->overhead = overhead;
+ packet->size = overhead;
return;
+ }
/* update dst or transport pathmtu if in need */
sk = asoc->base.sk;
@@ -140,23 +157,14 @@ void sctp_packet_init(struct sctp_packet *packet,
struct sctp_transport *transport,
__u16 sport, __u16 dport)
{
- struct sctp_association *asoc = transport->asoc;
- size_t overhead;
-
pr_debug("%s: packet:%p transport:%p\n", __func__, packet, transport);
packet->transport = transport;
packet->source_port = sport;
packet->destination_port = dport;
INIT_LIST_HEAD(&packet->chunk_list);
- if (asoc) {
- struct sctp_sock *sp = sctp_sk(asoc->base.sk);
- overhead = sp->pf->af->net_header_len;
- } else {
- overhead = sizeof(struct ipv6hdr);
- }
- overhead += sizeof(struct sctphdr);
- packet->overhead = overhead;
+ /* The overhead will be calculated by sctp_packet_config() */
+ packet->overhead = 0;
sctp_packet_reset(packet);
packet->vtag = 0;
}
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index a24cde236330..d685f8456762 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -187,6 +187,45 @@ int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *bp,
return error;
}
+/* Copy over any ip options */
+static void sctp_v4_copy_ip_options(struct sock *sk, struct sock *newsk)
+{
+ struct inet_sock *newinet, *inet = inet_sk(sk);
+ struct ip_options_rcu *inet_opt, *newopt = NULL;
+
+ newinet = inet_sk(newsk);
+
+ rcu_read_lock();
+ inet_opt = rcu_dereference(inet->inet_opt);
+ if (inet_opt) {
+ newopt = sock_kmalloc(newsk, sizeof(*inet_opt) +
+ inet_opt->opt.optlen, GFP_ATOMIC);
+ if (newopt)
+ memcpy(newopt, inet_opt, sizeof(*inet_opt) +
+ inet_opt->opt.optlen);
+ else
+ pr_err("%s: Failed to copy ip options\n", __func__);
+ }
+ RCU_INIT_POINTER(newinet->inet_opt, newopt);
+ rcu_read_unlock();
+}
+
+/* Account for the IP options */
+static int sctp_v4_ip_options_len(struct sock *sk)
+{
+ struct inet_sock *inet = inet_sk(sk);
+ struct ip_options_rcu *inet_opt;
+ int len = 0;
+
+ rcu_read_lock();
+ inet_opt = rcu_dereference(inet->inet_opt);
+ if (inet_opt)
+ len = inet_opt->opt.optlen;
+
+ rcu_read_unlock();
+ return len;
+}
+
/* Initialize a sctp_addr from in incoming skb. */
static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
int is_saddr)
@@ -538,6 +577,8 @@ static struct sock *sctp_v4_create_accept_sk(struct sock *sk,
sctp_copy_sock(newsk, sk, asoc);
sock_reset_flag(newsk, SOCK_ZAPPED);
+ sctp_v4_copy_ip_options(sk, newsk);
+
newinet = inet_sk(newsk);
newinet->inet_daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr;
@@ -956,6 +997,7 @@ static struct sctp_pf sctp_pf_inet = {
.addr_to_user = sctp_v4_addr_to_user,
.to_sk_saddr = sctp_v4_to_sk_saddr,
.to_sk_daddr = sctp_v4_to_sk_daddr,
+ .copy_ip_options = sctp_v4_copy_ip_options,
.af = &sctp_af_inet
};
@@ -1040,6 +1082,7 @@ static struct sctp_af sctp_af_inet = {
.ecn_capable = sctp_v4_ecn_capable,
.net_header_len = sizeof(struct iphdr),
.sockaddr_len = sizeof(struct sockaddr_in),
+ .ip_options_len = sctp_v4_ip_options_len,
#ifdef CONFIG_COMPAT
.compat_setsockopt = compat_ip_setsockopt,
.compat_getsockopt = compat_ip_getsockopt,
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index cc20bc39ee7c..5a4fb1dc8400 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -3098,6 +3098,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
if (af->is_any(&addr))
memcpy(&addr, &asconf->source, sizeof(addr));
+ if (security_sctp_bind_connect(asoc->ep->base.sk,
+ SCTP_PARAM_ADD_IP,
+ (struct sockaddr *)&addr,
+ af->sockaddr_len))
+ return SCTP_ERROR_REQ_REFUSED;
+
/* ADDIP 4.3 D9) If an endpoint receives an ADD IP address
* request and does not have the local resources to add this
* new address to the association, it MUST return an Error
@@ -3164,6 +3170,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc,
if (af->is_any(&addr))
memcpy(&addr.v4, sctp_source(asconf), sizeof(addr));
+ if (security_sctp_bind_connect(asoc->ep->base.sk,
+ SCTP_PARAM_SET_PRIMARY,
+ (struct sockaddr *)&addr,
+ af->sockaddr_len))
+ return SCTP_ERROR_REQ_REFUSED;
+
peer = sctp_assoc_lookup_paddr(asoc, &addr);
if (!peer)
return SCTP_ERROR_DNS_FAILED;
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index cc56a67dbb4d..dd0594a10961 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -321,6 +321,11 @@ enum sctp_disposition sctp_sf_do_5_1B_init(struct net *net,
struct sctp_packet *packet;
int len;
+ /* Update socket peer label if first association. */
+ if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+ chunk->skb))
+ return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
/* 6.10 Bundling
* An endpoint MUST NOT bundle INIT, INIT ACK or
* SHUTDOWN COMPLETE with any other chunks.
@@ -922,6 +927,9 @@ enum sctp_disposition sctp_sf_do_5_1E_ca(struct net *net,
*/
sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL());
+ /* Set peer label for connection. */
+ security_inet_conn_established(ep->base.sk, chunk->skb);
+
/* RFC 2960 5.1 Normal Establishment of an Association
*
* E) Upon reception of the COOKIE ACK, endpoint "A" will move
@@ -1459,6 +1467,11 @@ static enum sctp_disposition sctp_sf_do_unexpected_init(
struct sctp_packet *packet;
int len;
+ /* Update socket peer label if first association. */
+ if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+ chunk->skb))
+ return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
/* 6.10 Bundling
* An endpoint MUST NOT bundle INIT, INIT ACK or
* SHUTDOWN COMPLETE with any other chunks.
@@ -2145,6 +2158,11 @@ enum sctp_disposition sctp_sf_do_5_2_4_dupcook(
}
}
+ /* Update socket peer label if first association. */
+ if (security_sctp_assoc_request((struct sctp_endpoint *)ep,
+ chunk->skb))
+ return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
+
/* Set temp so that it won't be added into hashtable */
new_asoc->temp = 1;
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 7a10ae3c3d82..2a2e094560de 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1046,6 +1046,12 @@ static int sctp_setsockopt_bindx(struct sock *sk,
/* Do the work. */
switch (op) {
case SCTP_BINDX_ADD_ADDR:
+ /* Allow security module to validate bindx addresses. */
+ err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_BINDX_ADD,
+ (struct sockaddr *)kaddrs,
+ addrs_size);
+ if (err)
+ goto out;
err = sctp_bindx_add(sk, kaddrs, addrcnt);
if (err)
goto out;
@@ -1255,6 +1261,7 @@ static int __sctp_connect(struct sock *sk,
if (assoc_id)
*assoc_id = asoc->assoc_id;
+
err = sctp_wait_for_connect(asoc, &timeo);
/* Note: the asoc may be freed after the return of
* sctp_wait_for_connect.
@@ -1350,7 +1357,16 @@ static int __sctp_setsockopt_connectx(struct sock *sk,
if (unlikely(IS_ERR(kaddrs)))
return PTR_ERR(kaddrs);
+ /* Allow security module to validate connectx addresses. */
+ err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_CONNECTX,
+ (struct sockaddr *)kaddrs,
+ addrs_size);
+ if (err)
+ goto out_free;
+
err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
+
+out_free:
kvfree(kaddrs);
return err;
@@ -1680,6 +1696,7 @@ static int sctp_sendmsg_new_asoc(struct sock *sk, __u16 sflags,
struct sctp_association *asoc;
enum sctp_scope scope;
struct cmsghdr *cmsg;
+ struct sctp_af *af;
int err;
*tp = NULL;
@@ -1705,6 +1722,21 @@ static int sctp_sendmsg_new_asoc(struct sock *sk, __u16 sflags,
scope = sctp_scope(daddr);
+ /* Label connection socket for first association 1-to-many
+ * style for client sequence socket()->sendmsg(). This
+ * needs to be done before sctp_assoc_add_peer() as that will
+ * set up the initial packet that needs to account for any
+ * security ip options (CIPSO/CALIPSO) added to the packet.
+ */
+ af = sctp_get_af_specific(daddr->sa.sa_family);
+ if (!af)
+ return -EINVAL;
+ err = security_sctp_bind_connect(sk, SCTP_SENDMSG_CONNECT,
+ (struct sockaddr *)daddr,
+ af->sockaddr_len);
+ if (err < 0)
+ return err;
+
asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL);
if (!asoc)
return -ENOMEM;
@@ -2932,6 +2964,8 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
{
struct sctp_prim prim;
struct sctp_transport *trans;
+ struct sctp_af *af;
+ int err;
if (optlen != sizeof(struct sctp_prim))
return -EINVAL;
@@ -2939,6 +2973,17 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval,
if (copy_from_user(&prim, optval, sizeof(struct sctp_prim)))
return -EFAULT;
+ /* Allow security module to validate address but need address len. */
+ af = sctp_get_af_specific(prim.ssp_addr.ss_family);
+ if (!af)
+ return -EINVAL;
+
+ err = security_sctp_bind_connect(sk, SCTP_PRIMARY_ADDR,
+ (struct sockaddr *)&prim.ssp_addr,
+ af->sockaddr_len);
+ if (err)
+ return err;
+
trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id);
if (!trans)
return -EINVAL;
@@ -3161,6 +3206,7 @@ static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsign
static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen)
{
struct sctp_sock *sp = sctp_sk(sk);
+ struct sctp_af *af = sp->pf->af;
struct sctp_assoc_value params;
struct sctp_association *asoc;
int val;
@@ -3185,7 +3231,8 @@ static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned
if (val) {
int min_len, max_len;
- min_len = SCTP_DEFAULT_MINSEGMENT - sp->pf->af->net_header_len;
+ min_len = SCTP_DEFAULT_MINSEGMENT - af->net_header_len;
+ min_len -= af->ip_options_len(sk);
min_len -= sizeof(struct sctphdr) +
sizeof(struct sctp_data_chunk);
@@ -3198,7 +3245,8 @@ static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned
asoc = sctp_id2assoc(sk, params.assoc_id);
if (asoc) {
if (val == 0) {
- val = asoc->pathmtu - sp->pf->af->net_header_len;
+ val = asoc->pathmtu - af->net_header_len;
+ val -= af->ip_options_len(sk);
val -= sizeof(struct sctphdr) +
sctp_datachk_len(&asoc->stream);
}
@@ -3267,6 +3315,13 @@ static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optva
if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr))
return -EADDRNOTAVAIL;
+ /* Allow security module to validate address. */
+ err = security_sctp_bind_connect(sk, SCTP_SET_PEER_PRIMARY_ADDR,
+ (struct sockaddr *)&prim.sspp_addr,
+ af->sockaddr_len);
+ if (err)
+ return err;
+
/* Create an ASCONF chunk with SET_PRIMARY parameter */
chunk = sctp_make_asconf_set_prim(asoc,
(union sctp_addr *)&prim.sspp_addr);
@@ -5140,9 +5195,11 @@ int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp)
sctp_copy_sock(sock->sk, sk, asoc);
/* Make peeled-off sockets more like 1-1 accepted sockets.
- * Set the daddr and initialize id to something more random
+ * Set the daddr and initialize id to something more random and also
+ * copy over any ip options.
*/
sp->pf->to_sk_daddr(&asoc->peer.primary_addr, sk);
+ sp->pf->copy_ip_options(sk, sock->sk);
/* Populate the fields of the newsk from the oldsk and migrate the
* asoc to the newsk.
@@ -8465,6 +8522,8 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
{
struct inet_sock *inet = inet_sk(sk);
struct inet_sock *newinet;
+ struct sctp_sock *sp = sctp_sk(sk);
+ struct sctp_endpoint *ep = sp->ep;
newsk->sk_type = sk->sk_type;
newsk->sk_bound_dev_if = sk->sk_bound_dev_if;
@@ -8507,7 +8566,10 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk,
if (newsk->sk_flags & SK_FLAGS_TIMESTAMP)
net_enable_timestamp();
- security_sk_clone(sk, newsk);
+ /* Set newsk security attributes from orginal sk and connection
+ * security attribute from ep.
+ */
+ security_sctp_sk_clone(ep, sk, newsk);
}
static inline void sctp_copy_descendant(struct sock *sk_to,