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-rw-r--r--net/sctp/sysctl.c477
1 files changed, 363 insertions, 114 deletions
diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c
index 9a5c4c9eddaf..15e7db9a3ab2 100644
--- a/net/sctp/sysctl.c
+++ b/net/sctp/sysctl.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/* SCTP kernel implementation
* (C) Copyright IBM Corp. 2002, 2004
* Copyright (c) 2002 Intel Corp.
@@ -6,29 +7,9 @@
*
* Sysctl related interfaces for SCTP.
*
- * This SCTP implementation 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, or (at your option)
- * any later version.
- *
- * This SCTP implementation is distributed in the hope that it
- * will be useful, but WITHOUT ANY WARRANTY; without even the implied
- * ************************
- * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
- * See the GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with GNU CC; see the file COPYING. If not, write to
- * the Free Software Foundation, 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
- *
* Please send any bug reports or fixes you make to the
* email address(es):
- * lksctp developers <lksctp-developers@lists.sourceforge.net>
- *
- * Or submit a bug report through the following website:
- * http://www.sf.net/projects/lksctp
+ * lksctp developers <linux-sctp@vger.kernel.org>
*
* Written or modified by:
* Mingqin Liu <liuming@us.ibm.com>
@@ -36,37 +17,47 @@
* Ardelle Fan <ardelle.fan@intel.com>
* Ryan Layer <rmlayer@us.ibm.com>
* Sridhar Samudrala <sri@us.ibm.com>
- *
- * Any bugs reported given to us we will try to fix... any fixes shared will
- * be incorporated into the next SCTP release.
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <net/sctp/structs.h>
#include <net/sctp/sctp.h>
#include <linux/sysctl.h>
-static int zero = 0;
-static int one = 1;
static int timer_max = 86400000; /* ms in one day */
-static int int_max = INT_MAX;
static int sack_timer_min = 1;
static int sack_timer_max = 500;
-static int addr_scope_max = 3; /* check sctp_scope_policy_t in include/net/sctp/constants.h for max entries */
+static int addr_scope_max = SCTP_SCOPE_POLICY_MAX;
static int rwnd_scale_max = 16;
+static int rto_alpha_min = 0;
+static int rto_beta_min = 0;
+static int rto_alpha_max = 1000;
+static int rto_beta_max = 1000;
+static int pf_expose_max = SCTP_PF_EXPOSE_MAX;
+static int ps_retrans_max = SCTP_PS_RETRANS_MAX;
+static int udp_port_max = 65535;
+
static unsigned long max_autoclose_min = 0;
static unsigned long max_autoclose_max =
(MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
-extern long sysctl_sctp_mem[3];
-extern int sysctl_sctp_rmem[3];
-extern int sysctl_sctp_wmem[3];
-
-static int proc_sctp_do_hmac_alg(struct ctl_table *ctl,
- int write,
- void __user *buffer, size_t *lenp,
+static int proc_sctp_do_hmac_alg(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos);
+static int proc_sctp_do_rto_min(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos);
+static int proc_sctp_do_rto_max(const struct ctl_table *ctl, int write, void *buffer,
+ size_t *lenp, loff_t *ppos);
+static int proc_sctp_do_udp_port(const struct ctl_table *ctl, int write, void *buffer,
+ size_t *lenp, loff_t *ppos);
+static int proc_sctp_do_alpha_beta(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos);
+static int proc_sctp_do_auth(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos);
+static int proc_sctp_do_probe_interval(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos);
- loff_t *ppos);
static struct ctl_table sctp_table[] = {
{
.procname = "sctp_mem",
@@ -89,51 +80,81 @@ static struct ctl_table sctp_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec,
},
-
- { /* sentinel */ }
};
+/* The following index defines are used in sctp_sysctl_net_register().
+ * If you add new items to the sctp_net_table, please ensure that
+ * the index values of these defines hold the same meaning indicated by
+ * their macro names when they appear in sctp_net_table.
+ */
+#define SCTP_RTO_MIN_IDX 0
+#define SCTP_RTO_MAX_IDX 1
+#define SCTP_PF_RETRANS_IDX 2
+#define SCTP_PS_RETRANS_IDX 3
+
static struct ctl_table sctp_net_table[] = {
- {
- .procname = "rto_initial",
- .data = &init_net.sctp.rto_initial,
+ [SCTP_RTO_MIN_IDX] = {
+ .procname = "rto_min",
+ .data = &init_net.sctp.rto_min,
.maxlen = sizeof(unsigned int),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &one,
- .extra2 = &timer_max
+ .proc_handler = proc_sctp_do_rto_min,
+ .extra1 = SYSCTL_ONE,
+ .extra2 = &init_net.sctp.rto_max
},
- {
- .procname = "rto_min",
- .data = &init_net.sctp.rto_min,
+ [SCTP_RTO_MAX_IDX] = {
+ .procname = "rto_max",
+ .data = &init_net.sctp.rto_max,
.maxlen = sizeof(unsigned int),
.mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &one,
+ .proc_handler = proc_sctp_do_rto_max,
+ .extra1 = &init_net.sctp.rto_min,
.extra2 = &timer_max
},
+ [SCTP_PF_RETRANS_IDX] = {
+ .procname = "pf_retrans",
+ .data = &init_net.sctp.pf_retrans,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = &init_net.sctp.ps_retrans,
+ },
+ [SCTP_PS_RETRANS_IDX] = {
+ .procname = "ps_retrans",
+ .data = &init_net.sctp.ps_retrans,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = &init_net.sctp.pf_retrans,
+ .extra2 = &ps_retrans_max,
+ },
{
- .procname = "rto_max",
- .data = &init_net.sctp.rto_max,
+ .procname = "rto_initial",
+ .data = &init_net.sctp.rto_initial,
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &one,
+ .extra1 = SYSCTL_ONE,
.extra2 = &timer_max
},
{
.procname = "rto_alpha_exp_divisor",
.data = &init_net.sctp.rto_alpha,
.maxlen = sizeof(int),
- .mode = 0444,
- .proc_handler = proc_dointvec,
+ .mode = 0644,
+ .proc_handler = proc_sctp_do_alpha_beta,
+ .extra1 = &rto_alpha_min,
+ .extra2 = &rto_alpha_max,
},
{
.procname = "rto_beta_exp_divisor",
.data = &init_net.sctp.rto_beta,
.maxlen = sizeof(int),
- .mode = 0444,
- .proc_handler = proc_dointvec,
+ .mode = 0644,
+ .proc_handler = proc_sctp_do_alpha_beta,
+ .extra1 = &rto_beta_min,
+ .extra2 = &rto_beta_max,
},
{
.procname = "max_burst",
@@ -141,8 +162,8 @@ static struct ctl_table sctp_net_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- .extra2 = &int_max
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_INT_MAX,
},
{
.procname = "cookie_preserve_enable",
@@ -153,6 +174,7 @@ static struct ctl_table sctp_net_table[] = {
},
{
.procname = "cookie_hmac_alg",
+ .data = &init_net.sctp.cookie_auth_enable,
.maxlen = 8,
.mode = 0644,
.proc_handler = proc_sctp_do_hmac_alg,
@@ -163,7 +185,7 @@ static struct ctl_table sctp_net_table[] = {
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &one,
+ .extra1 = SYSCTL_ONE,
.extra2 = &timer_max
},
{
@@ -181,7 +203,7 @@ static struct ctl_table sctp_net_table[] = {
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &one,
+ .extra1 = SYSCTL_ONE,
.extra2 = &timer_max
},
{
@@ -190,8 +212,8 @@ static struct ctl_table sctp_net_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &one,
- .extra2 = &int_max
+ .extra1 = SYSCTL_ONE,
+ .extra2 = SYSCTL_INT_MAX,
},
{
.procname = "path_max_retrans",
@@ -199,8 +221,8 @@ static struct ctl_table sctp_net_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &one,
- .extra2 = &int_max
+ .extra1 = SYSCTL_ONE,
+ .extra2 = SYSCTL_INT_MAX,
},
{
.procname = "max_init_retransmits",
@@ -208,17 +230,8 @@ static struct ctl_table sctp_net_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &one,
- .extra2 = &int_max
- },
- {
- .procname = "pf_retrans",
- .data = &init_net.sctp.pf_retrans,
- .maxlen = sizeof(int),
- .mode = 0644,
- .proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
- .extra2 = &int_max
+ .extra1 = SYSCTL_ONE,
+ .extra2 = SYSCTL_INT_MAX,
},
{
.procname = "sndbuf_policy",
@@ -263,19 +276,65 @@ static struct ctl_table sctp_net_table[] = {
.proc_handler = proc_dointvec,
},
{
+ .procname = "reconf_enable",
+ .data = &init_net.sctp.reconf_enable,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
.procname = "auth_enable",
.data = &init_net.sctp.auth_enable,
.maxlen = sizeof(int),
.mode = 0644,
+ .proc_handler = proc_sctp_do_auth,
+ },
+ {
+ .procname = "intl_enable",
+ .data = &init_net.sctp.intl_enable,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "ecn_enable",
+ .data = &init_net.sctp.ecn_enable,
+ .maxlen = sizeof(int),
+ .mode = 0644,
.proc_handler = proc_dointvec,
},
{
+ .procname = "plpmtud_probe_interval",
+ .data = &init_net.sctp.probe_interval,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_sctp_do_probe_interval,
+ },
+ {
+ .procname = "udp_port",
+ .data = &init_net.sctp.udp_port,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_sctp_do_udp_port,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = &udp_port_max,
+ },
+ {
+ .procname = "encap_port",
+ .data = &init_net.sctp.encap_port,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = &udp_port_max,
+ },
+ {
.procname = "addr_scope_policy",
.data = &init_net.sctp.scope_policy,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_minmax,
- .extra1 = &zero,
+ .extra1 = SYSCTL_ZERO,
.extra2 = &addr_scope_max,
},
{
@@ -284,7 +343,7 @@ static struct ctl_table sctp_net_table[] = {
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec_minmax,
- .extra1 = &one,
+ .extra1 = SYSCTL_ONE,
.extra2 = &rwnd_scale_max,
},
{
@@ -296,53 +355,232 @@ static struct ctl_table sctp_net_table[] = {
.extra1 = &max_autoclose_min,
.extra2 = &max_autoclose_max,
},
-
- { /* sentinel */ }
+#ifdef CONFIG_NET_L3_MASTER_DEV
+ {
+ .procname = "l3mdev_accept",
+ .data = &init_net.sctp.l3mdev_accept,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = SYSCTL_ONE,
+ },
+#endif
+ {
+ .procname = "pf_enable",
+ .data = &init_net.sctp.pf_enable,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+ },
+ {
+ .procname = "pf_expose",
+ .data = &init_net.sctp.pf_expose,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = SYSCTL_ZERO,
+ .extra2 = &pf_expose_max,
+ },
};
-static int proc_sctp_do_hmac_alg(struct ctl_table *ctl,
- int write,
- void __user *buffer, size_t *lenp,
- loff_t *ppos)
+static int proc_sctp_do_hmac_alg(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
{
- struct net *net = current->nsproxy->net_ns;
- char tmp[8];
+ struct net *net = container_of(ctl->data, struct net,
+ sctp.cookie_auth_enable);
struct ctl_table tbl;
+ char tmp[8] = {0};
int ret;
- int changed = 0;
- char *none = "none";
memset(&tbl, 0, sizeof(struct ctl_table));
if (write) {
tbl.data = tmp;
- tbl.maxlen = 8;
- } else {
- tbl.data = net->sctp.sctp_hmac_alg ? : none;
- tbl.maxlen = strlen(tbl.data);
- }
- ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
-
- if (write) {
-#ifdef CONFIG_CRYPTO_MD5
- if (!strncmp(tmp, "md5", 3)) {
- net->sctp.sctp_hmac_alg = "md5";
- changed = 1;
+ tbl.maxlen = sizeof(tmp) - 1;
+ ret = proc_dostring(&tbl, 1, buffer, lenp, ppos);
+ if (ret)
+ return ret;
+ if (!strcmp(tmp, "sha256")) {
+ net->sctp.cookie_auth_enable = 1;
+ return 0;
}
-#endif
-#ifdef CONFIG_CRYPTO_SHA1
- if (!strncmp(tmp, "sha1", 4)) {
- net->sctp.sctp_hmac_alg = "sha1";
- changed = 1;
+ if (!strcmp(tmp, "none")) {
+ net->sctp.cookie_auth_enable = 0;
+ return 0;
}
-#endif
- if (!strncmp(tmp, "none", 4)) {
- net->sctp.sctp_hmac_alg = NULL;
- changed = 1;
+ return -EINVAL;
+ }
+ if (net->sctp.cookie_auth_enable)
+ tbl.data = (char *)"sha256";
+ else
+ tbl.data = (char *)"none";
+ tbl.maxlen = strlen(tbl.data);
+ return proc_dostring(&tbl, 0, buffer, lenp, ppos);
+}
+
+static int proc_sctp_do_rto_min(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net *net = container_of(ctl->data, struct net, sctp.rto_min);
+ unsigned int min = *(unsigned int *) ctl->extra1;
+ unsigned int max = *(unsigned int *) ctl->extra2;
+ struct ctl_table tbl;
+ int ret, new_value;
+
+ memset(&tbl, 0, sizeof(struct ctl_table));
+ tbl.maxlen = sizeof(unsigned int);
+
+ if (write)
+ tbl.data = &new_value;
+ else
+ tbl.data = &net->sctp.rto_min;
+
+ ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
+ if (write && ret == 0) {
+ if (new_value > max || new_value < min)
+ return -EINVAL;
+
+ net->sctp.rto_min = new_value;
+ }
+
+ return ret;
+}
+
+static int proc_sctp_do_rto_max(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net *net = container_of(ctl->data, struct net, sctp.rto_max);
+ unsigned int min = *(unsigned int *) ctl->extra1;
+ unsigned int max = *(unsigned int *) ctl->extra2;
+ struct ctl_table tbl;
+ int ret, new_value;
+
+ memset(&tbl, 0, sizeof(struct ctl_table));
+ tbl.maxlen = sizeof(unsigned int);
+
+ if (write)
+ tbl.data = &new_value;
+ else
+ tbl.data = &net->sctp.rto_max;
+
+ ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
+ if (write && ret == 0) {
+ if (new_value > max || new_value < min)
+ return -EINVAL;
+
+ net->sctp.rto_max = new_value;
+ }
+
+ return ret;
+}
+
+static int proc_sctp_do_alpha_beta(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ if (write)
+ pr_warn_once("Changing rto_alpha or rto_beta may lead to "
+ "suboptimal rtt/srtt estimations!\n");
+
+ return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
+}
+
+static int proc_sctp_do_auth(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net *net = container_of(ctl->data, struct net, sctp.auth_enable);
+ struct ctl_table tbl;
+ int new_value, ret;
+
+ memset(&tbl, 0, sizeof(struct ctl_table));
+ tbl.maxlen = sizeof(unsigned int);
+
+ if (write)
+ tbl.data = &new_value;
+ else
+ tbl.data = &net->sctp.auth_enable;
+
+ ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
+ if (write && ret == 0) {
+ struct sock *sk = net->sctp.ctl_sock;
+
+ net->sctp.auth_enable = new_value;
+ /* Update the value in the control socket */
+ lock_sock(sk);
+ sctp_sk(sk)->ep->auth_enable = new_value;
+ release_sock(sk);
+ }
+
+ return ret;
+}
+
+static DEFINE_MUTEX(sctp_sysctl_mutex);
+
+static int proc_sctp_do_udp_port(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net *net = container_of(ctl->data, struct net, sctp.udp_port);
+ unsigned int min = *(unsigned int *)ctl->extra1;
+ unsigned int max = *(unsigned int *)ctl->extra2;
+ struct ctl_table tbl;
+ int ret, new_value;
+
+ memset(&tbl, 0, sizeof(struct ctl_table));
+ tbl.maxlen = sizeof(unsigned int);
+
+ if (write)
+ tbl.data = &new_value;
+ else
+ tbl.data = &net->sctp.udp_port;
+
+ ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
+ if (write && ret == 0) {
+ struct sock *sk = net->sctp.ctl_sock;
+
+ if (new_value > max || new_value < min)
+ return -EINVAL;
+
+ mutex_lock(&sctp_sysctl_mutex);
+ net->sctp.udp_port = new_value;
+ sctp_udp_sock_stop(net);
+ if (new_value) {
+ ret = sctp_udp_sock_start(net);
+ if (ret)
+ net->sctp.udp_port = 0;
}
- if (!changed)
- ret = -EINVAL;
+ /* Update the value in the control socket */
+ lock_sock(sk);
+ sctp_sk(sk)->udp_port = htons(net->sctp.udp_port);
+ release_sock(sk);
+ mutex_unlock(&sctp_sysctl_mutex);
+ }
+
+ return ret;
+}
+
+static int proc_sctp_do_probe_interval(const struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net *net = container_of(ctl->data, struct net,
+ sctp.probe_interval);
+ struct ctl_table tbl;
+ int ret, new_value;
+
+ memset(&tbl, 0, sizeof(struct ctl_table));
+ tbl.maxlen = sizeof(unsigned int);
+
+ if (write)
+ tbl.data = &new_value;
+ else
+ tbl.data = &net->sctp.probe_interval;
+
+ ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
+ if (write && ret == 0) {
+ if (new_value && new_value < SCTP_PROBE_TIMER_MIN)
+ return -EINVAL;
+
+ net->sctp.probe_interval = new_value;
}
return ret;
@@ -350,6 +588,7 @@ static int proc_sctp_do_hmac_alg(struct ctl_table *ctl,
int sctp_sysctl_net_register(struct net *net)
{
+ size_t table_size = ARRAY_SIZE(sctp_net_table);
struct ctl_table *table;
int i;
@@ -357,23 +596,33 @@ int sctp_sysctl_net_register(struct net *net)
if (!table)
return -ENOMEM;
- for (i = 0; table[i].data; i++)
+ for (i = 0; i < table_size; i++)
table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
- net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
+ table[SCTP_RTO_MIN_IDX].extra2 = &net->sctp.rto_max;
+ table[SCTP_RTO_MAX_IDX].extra1 = &net->sctp.rto_min;
+ table[SCTP_PF_RETRANS_IDX].extra2 = &net->sctp.ps_retrans;
+ table[SCTP_PS_RETRANS_IDX].extra1 = &net->sctp.pf_retrans;
+
+ net->sctp.sysctl_header = register_net_sysctl_sz(net, "net/sctp",
+ table, table_size);
+ if (net->sctp.sysctl_header == NULL) {
+ kfree(table);
+ return -ENOMEM;
+ }
return 0;
}
void sctp_sysctl_net_unregister(struct net *net)
{
- struct ctl_table *table;
+ const struct ctl_table *table;
table = net->sctp.sysctl_header->ctl_table_arg;
unregister_net_sysctl_table(net->sctp.sysctl_header);
kfree(table);
}
-static struct ctl_table_header * sctp_sysctl_header;
+static struct ctl_table_header *sctp_sysctl_header;
/* Sysctl registration. */
void sctp_sysctl_register(void)
generated by cgit (git 2.34.1) at 2025-12-22 02:05:28 +0000