net/sctp/sysctl.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* SCTP kernel implementation
   3  * (C) Copyright IBM Corp. 2002, 2004
   4  * Copyright (c) 2002 Intel Corp.
   5  *
   6  * This file is part of the SCTP kernel implementation
   7  *
   8  * Sysctl related interfaces for SCTP.
   9  *
  10  * Please send any bug reports or fixes you make to the
  11  * email address(es):
  12  *    lksctp developers <linux-sctp@vger.kernel.org>
  13  *
  14  * Written or modified by:
  15  *    Mingqin Liu           <liuming@us.ibm.com>
  16  *    Jon Grimm             <jgrimm@us.ibm.com>
  17  *    Ardelle Fan           <ardelle.fan@intel.com>
  18  *    Ryan Layer            <rmlayer@us.ibm.com>
  19  *    Sridhar Samudrala     <sri@us.ibm.com>
  20  */
  21
  22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  24 #include <net/sctp/structs.h>
  25 #include <net/sctp/sctp.h>
  26 #include <linux/sysctl.h>
  27
  28 static int timer_max = 86400000; /* ms in one day */
  29 static int sack_timer_min = 1;
  30 static int sack_timer_max = 500;
  31 static int addr_scope_max = SCTP_SCOPE_POLICY_MAX;
  32 static int rwnd_scale_max = 16;
  33 static int rto_alpha_min = 0;
  34 static int rto_beta_min = 0;
  35 static int rto_alpha_max = 1000;
  36 static int rto_beta_max = 1000;
  37
  38 static unsigned long max_autoclose_min = 0;
  39 static unsigned long max_autoclose_max =
  40         (MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
  41         ? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
  42
  43 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
  44                                 void __user *buffer, size_t *lenp,
  45                                 loff_t *ppos);
  46 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
  47                                 void __user *buffer, size_t *lenp,
  48                                 loff_t *ppos);
  49 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
  50                                 void __user *buffer, size_t *lenp,
  51                                 loff_t *ppos);
  52 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
  53                                    void __user *buffer, size_t *lenp,
  54                                    loff_t *ppos);
  55 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
  56                              void __user *buffer, size_t *lenp,
  57                              loff_t *ppos);
  58
  59 static struct ctl_table sctp_table[] = {
  60         {
  61                 .procname       = "sctp_mem",
  62                 .data           = &sysctl_sctp_mem,
  63                 .maxlen         = sizeof(sysctl_sctp_mem),
  64                 .mode           = 0644,
  65                 .proc_handler   = proc_doulongvec_minmax
  66         },
  67         {
  68                 .procname       = "sctp_rmem",
  69                 .data           = &sysctl_sctp_rmem,
  70                 .maxlen         = sizeof(sysctl_sctp_rmem),
  71                 .mode           = 0644,
  72                 .proc_handler   = proc_dointvec,
  73         },
  74         {
  75                 .procname       = "sctp_wmem",
  76                 .data           = &sysctl_sctp_wmem,
  77                 .maxlen         = sizeof(sysctl_sctp_wmem),
  78                 .mode           = 0644,
  79                 .proc_handler   = proc_dointvec,
  80         },
  81
  82         { /* sentinel */ }
  83 };
  84
  85 static struct ctl_table sctp_net_table[] = {
  86         {
  87                 .procname       = "rto_initial",
  88                 .data           = &init_net.sctp.rto_initial,
  89                 .maxlen         = sizeof(unsigned int),
  90                 .mode           = 0644,
  91                 .proc_handler   = proc_dointvec_minmax,
  92                 .extra1         = SYSCTL_ONE,
  93                 .extra2         = &timer_max
  94         },
  95         {
  96                 .procname       = "rto_min",
  97                 .data           = &init_net.sctp.rto_min,
  98                 .maxlen         = sizeof(unsigned int),
  99                 .mode           = 0644,
 100                 .proc_handler   = proc_sctp_do_rto_min,
 101                 .extra1         = SYSCTL_ONE,
 102                 .extra2         = &init_net.sctp.rto_max
 103         },
 104         {
 105                 .procname       = "rto_max",
 106                 .data           = &init_net.sctp.rto_max,
 107                 .maxlen         = sizeof(unsigned int),
 108                 .mode           = 0644,
 109                 .proc_handler   = proc_sctp_do_rto_max,
 110                 .extra1         = &init_net.sctp.rto_min,
 111                 .extra2         = &timer_max
 112         },
 113         {
 114                 .procname       = "rto_alpha_exp_divisor",
 115                 .data           = &init_net.sctp.rto_alpha,
 116                 .maxlen         = sizeof(int),
 117                 .mode           = 0644,
 118                 .proc_handler   = proc_sctp_do_alpha_beta,
 119                 .extra1         = &rto_alpha_min,
 120                 .extra2         = &rto_alpha_max,
 121         },
 122         {
 123                 .procname       = "rto_beta_exp_divisor",
 124                 .data           = &init_net.sctp.rto_beta,
 125                 .maxlen         = sizeof(int),
 126                 .mode           = 0644,
 127                 .proc_handler   = proc_sctp_do_alpha_beta,
 128                 .extra1         = &rto_beta_min,
 129                 .extra2         = &rto_beta_max,
 130         },
 131         {
 132                 .procname       = "max_burst",
 133                 .data           = &init_net.sctp.max_burst,
 134                 .maxlen         = sizeof(int),
 135                 .mode           = 0644,
 136                 .proc_handler   = proc_dointvec_minmax,
 137                 .extra1         = SYSCTL_ZERO,
 138                 .extra2         = SYSCTL_INT_MAX,
 139         },
 140         {
 141                 .procname       = "cookie_preserve_enable",
 142                 .data           = &init_net.sctp.cookie_preserve_enable,
 143                 .maxlen         = sizeof(int),
 144                 .mode           = 0644,
 145                 .proc_handler   = proc_dointvec,
 146         },
 147         {
 148                 .procname       = "cookie_hmac_alg",
 149                 .data           = &init_net.sctp.sctp_hmac_alg,
 150                 .maxlen         = 8,
 151                 .mode           = 0644,
 152                 .proc_handler   = proc_sctp_do_hmac_alg,
 153         },
 154         {
 155                 .procname       = "valid_cookie_life",
 156                 .data           = &init_net.sctp.valid_cookie_life,
 157                 .maxlen         = sizeof(unsigned int),
 158                 .mode           = 0644,
 159                 .proc_handler   = proc_dointvec_minmax,
 160                 .extra1         = SYSCTL_ONE,
 161                 .extra2         = &timer_max
 162         },
 163         {
 164                 .procname       = "sack_timeout",
 165                 .data           = &init_net.sctp.sack_timeout,
 166                 .maxlen         = sizeof(int),
 167                 .mode           = 0644,
 168                 .proc_handler   = proc_dointvec_minmax,
 169                 .extra1         = &sack_timer_min,
 170                 .extra2         = &sack_timer_max,
 171         },
 172         {
 173                 .procname       = "hb_interval",
 174                 .data           = &init_net.sctp.hb_interval,
 175                 .maxlen         = sizeof(unsigned int),
 176                 .mode           = 0644,
 177                 .proc_handler   = proc_dointvec_minmax,
 178                 .extra1         = SYSCTL_ONE,
 179                 .extra2         = &timer_max
 180         },
 181         {
 182                 .procname       = "association_max_retrans",
 183                 .data           = &init_net.sctp.max_retrans_association,
 184                 .maxlen         = sizeof(int),
 185                 .mode           = 0644,
 186                 .proc_handler   = proc_dointvec_minmax,
 187                 .extra1         = SYSCTL_ONE,
 188                 .extra2         = SYSCTL_INT_MAX,
 189         },
 190         {
 191                 .procname       = "path_max_retrans",
 192                 .data           = &init_net.sctp.max_retrans_path,
 193                 .maxlen         = sizeof(int),
 194                 .mode           = 0644,
 195                 .proc_handler   = proc_dointvec_minmax,
 196                 .extra1         = SYSCTL_ONE,
 197                 .extra2         = SYSCTL_INT_MAX,
 198         },
 199         {
 200                 .procname       = "max_init_retransmits",
 201                 .data           = &init_net.sctp.max_retrans_init,
 202                 .maxlen         = sizeof(int),
 203                 .mode           = 0644,
 204                 .proc_handler   = proc_dointvec_minmax,
 205                 .extra1         = SYSCTL_ONE,
 206                 .extra2         = SYSCTL_INT_MAX,
 207         },
 208         {
 209                 .procname       = "pf_retrans",
 210                 .data           = &init_net.sctp.pf_retrans,
 211                 .maxlen         = sizeof(int),
 212                 .mode           = 0644,
 213                 .proc_handler   = proc_dointvec_minmax,
 214                 .extra1         = SYSCTL_ZERO,
 215                 .extra2         = SYSCTL_INT_MAX,
 216         },
 217         {
 218                 .procname       = "sndbuf_policy",
 219                 .data           = &init_net.sctp.sndbuf_policy,
 220                 .maxlen         = sizeof(int),
 221                 .mode           = 0644,
 222                 .proc_handler   = proc_dointvec,
 223         },
 224         {
 225                 .procname       = "rcvbuf_policy",
 226                 .data           = &init_net.sctp.rcvbuf_policy,
 227                 .maxlen         = sizeof(int),
 228                 .mode           = 0644,
 229                 .proc_handler   = proc_dointvec,
 230         },
 231         {
 232                 .procname       = "default_auto_asconf",
 233                 .data           = &init_net.sctp.default_auto_asconf,
 234                 .maxlen         = sizeof(int),
 235                 .mode           = 0644,
 236                 .proc_handler   = proc_dointvec,
 237         },
 238         {
 239                 .procname       = "addip_enable",
 240                 .data           = &init_net.sctp.addip_enable,
 241                 .maxlen         = sizeof(int),
 242                 .mode           = 0644,
 243                 .proc_handler   = proc_dointvec,
 244         },
 245         {
 246                 .procname       = "addip_noauth_enable",
 247                 .data           = &init_net.sctp.addip_noauth,
 248                 .maxlen         = sizeof(int),
 249                 .mode           = 0644,
 250                 .proc_handler   = proc_dointvec,
 251         },
 252         {
 253                 .procname       = "prsctp_enable",
 254                 .data           = &init_net.sctp.prsctp_enable,
 255                 .maxlen         = sizeof(int),
 256                 .mode           = 0644,
 257                 .proc_handler   = proc_dointvec,
 258         },
 259         {
 260                 .procname       = "reconf_enable",
 261                 .data           = &init_net.sctp.reconf_enable,
 262                 .maxlen         = sizeof(int),
 263                 .mode           = 0644,
 264                 .proc_handler   = proc_dointvec,
 265         },
 266         {
 267                 .procname       = "auth_enable",
 268                 .data           = &init_net.sctp.auth_enable,
 269                 .maxlen         = sizeof(int),
 270                 .mode           = 0644,
 271                 .proc_handler   = proc_sctp_do_auth,
 272         },
 273         {
 274                 .procname       = "intl_enable",
 275                 .data           = &init_net.sctp.intl_enable,
 276                 .maxlen         = sizeof(int),
 277                 .mode           = 0644,
 278                 .proc_handler   = proc_dointvec,
 279         },
 280         {
 281                 .procname       = "ecn_enable",
 282                 .data           = &init_net.sctp.ecn_enable,
 283                 .maxlen         = sizeof(int),
 284                 .mode           = 0644,
 285                 .proc_handler   = proc_dointvec,
 286         },
 287         {
 288                 .procname       = "addr_scope_policy",
 289                 .data           = &init_net.sctp.scope_policy,
 290                 .maxlen         = sizeof(int),
 291                 .mode           = 0644,
 292                 .proc_handler   = proc_dointvec_minmax,
 293                 .extra1         = SYSCTL_ZERO,
 294                 .extra2         = &addr_scope_max,
 295         },
 296         {
 297                 .procname       = "rwnd_update_shift",
 298                 .data           = &init_net.sctp.rwnd_upd_shift,
 299                 .maxlen         = sizeof(int),
 300                 .mode           = 0644,
 301                 .proc_handler   = &proc_dointvec_minmax,
 302                 .extra1         = SYSCTL_ONE,
 303                 .extra2         = &rwnd_scale_max,
 304         },
 305         {
 306                 .procname       = "max_autoclose",
 307                 .data           = &init_net.sctp.max_autoclose,
 308                 .maxlen         = sizeof(unsigned long),
 309                 .mode           = 0644,
 310                 .proc_handler   = &proc_doulongvec_minmax,
 311                 .extra1         = &max_autoclose_min,
 312                 .extra2         = &max_autoclose_max,
 313         },
 314         {
 315                 .procname       = "pf_enable",
 316                 .data           = &init_net.sctp.pf_enable,
 317                 .maxlen         = sizeof(int),
 318                 .mode           = 0644,
 319                 .proc_handler   = proc_dointvec,
 320         },
 321
 322         { /* sentinel */ }
 323 };
 324
 325 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
 326                                 void __user *buffer, size_t *lenp,
 327                                 loff_t *ppos)
 328 {
 329         struct net *net = current->nsproxy->net_ns;
 330         struct ctl_table tbl;
 331         bool changed = false;
 332         char *none = "none";
 333         char tmp[8] = {0};
 334         int ret;
 335
 336         memset(&tbl, 0, sizeof(struct ctl_table));
 337
 338         if (write) {
 339                 tbl.data = tmp;
 340                 tbl.maxlen = sizeof(tmp);
 341         } else {
 342                 tbl.data = net->sctp.sctp_hmac_alg ? : none;
 343                 tbl.maxlen = strlen(tbl.data);
 344         }
 345
 346         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 347         if (write && ret == 0) {
 348 #ifdef CONFIG_CRYPTO_MD5
 349                 if (!strncmp(tmp, "md5", 3)) {
 350                         net->sctp.sctp_hmac_alg = "md5";
 351                         changed = true;
 352                 }
 353 #endif
 354 #ifdef CONFIG_CRYPTO_SHA1
 355                 if (!strncmp(tmp, "sha1", 4)) {
 356                         net->sctp.sctp_hmac_alg = "sha1";
 357                         changed = true;
 358                 }
 359 #endif
 360                 if (!strncmp(tmp, "none", 4)) {
 361                         net->sctp.sctp_hmac_alg = NULL;
 362                         changed = true;
 363                 }
 364                 if (!changed)
 365                         ret = -EINVAL;
 366         }
 367
 368         return ret;
 369 }
 370
 371 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
 372                                 void __user *buffer, size_t *lenp,
 373                                 loff_t *ppos)
 374 {
 375         struct net *net = current->nsproxy->net_ns;
 376         unsigned int min = *(unsigned int *) ctl->extra1;
 377         unsigned int max = *(unsigned int *) ctl->extra2;
 378         struct ctl_table tbl;
 379         int ret, new_value;
 380
 381         memset(&tbl, 0, sizeof(struct ctl_table));
 382         tbl.maxlen = sizeof(unsigned int);
 383
 384         if (write)
 385                 tbl.data = &new_value;
 386         else
 387                 tbl.data = &net->sctp.rto_min;
 388
 389         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 390         if (write && ret == 0) {
 391                 if (new_value > max || new_value < min)
 392                         return -EINVAL;
 393
 394                 net->sctp.rto_min = new_value;
 395         }
 396
 397         return ret;
 398 }
 399
 400 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
 401                                 void __user *buffer, size_t *lenp,
 402                                 loff_t *ppos)
 403 {
 404         struct net *net = current->nsproxy->net_ns;
 405         unsigned int min = *(unsigned int *) ctl->extra1;
 406         unsigned int max = *(unsigned int *) ctl->extra2;
 407         struct ctl_table tbl;
 408         int ret, new_value;
 409
 410         memset(&tbl, 0, sizeof(struct ctl_table));
 411         tbl.maxlen = sizeof(unsigned int);
 412
 413         if (write)
 414                 tbl.data = &new_value;
 415         else
 416                 tbl.data = &net->sctp.rto_max;
 417
 418         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 419         if (write && ret == 0) {
 420                 if (new_value > max || new_value < min)
 421                         return -EINVAL;
 422
 423                 net->sctp.rto_max = new_value;
 424         }
 425
 426         return ret;
 427 }
 428
 429 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
 430                                    void __user *buffer, size_t *lenp,
 431                                    loff_t *ppos)
 432 {
 433         if (write)
 434                 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
 435                              "suboptimal rtt/srtt estimations!\n");
 436
 437         return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
 438 }
 439
 440 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
 441                              void __user *buffer, size_t *lenp,
 442                              loff_t *ppos)
 443 {
 444         struct net *net = current->nsproxy->net_ns;
 445         struct ctl_table tbl;
 446         int new_value, ret;
 447
 448         memset(&tbl, 0, sizeof(struct ctl_table));
 449         tbl.maxlen = sizeof(unsigned int);
 450
 451         if (write)
 452                 tbl.data = &new_value;
 453         else
 454                 tbl.data = &net->sctp.auth_enable;
 455
 456         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 457         if (write && ret == 0) {
 458                 struct sock *sk = net->sctp.ctl_sock;
 459
 460                 net->sctp.auth_enable = new_value;
 461                 /* Update the value in the control socket */
 462                 lock_sock(sk);
 463                 sctp_sk(sk)->ep->auth_enable = new_value;
 464                 release_sock(sk);
 465         }
 466
 467         return ret;
 468 }
 469
 470 int sctp_sysctl_net_register(struct net *net)
 471 {
 472         struct ctl_table *table;
 473         int i;
 474
 475         table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
 476         if (!table)
 477                 return -ENOMEM;
 478
 479         for (i = 0; table[i].data; i++)
 480                 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
 481
 482         net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
 483         if (net->sctp.sysctl_header == NULL) {
 484                 kfree(table);
 485                 return -ENOMEM;
 486         }
 487         return 0;
 488 }
 489
 490 void sctp_sysctl_net_unregister(struct net *net)
 491 {
 492         struct ctl_table *table;
 493
 494         table = net->sctp.sysctl_header->ctl_table_arg;
 495         unregister_net_sysctl_table(net->sctp.sysctl_header);
 496         kfree(table);
 497 }
 498
 499 static struct ctl_table_header *sctp_sysctl_header;
 500
 501 /* Sysctl registration.  */
 502 void sctp_sysctl_register(void)
 503 {
 504         sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
 505 }
 506
 507 /* Sysctl deregistration.  */
 508 void sctp_sysctl_unregister(void)
 509 {
 510         unregister_net_sysctl_table(sctp_sysctl_header);
 511 }