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 static int pf_expose_max = SCTP_PF_EXPOSE_MAX;
  38 static int ps_retrans_max = SCTP_PS_RETRANS_MAX;
  39
  40 static unsigned long max_autoclose_min = 0;
  41 static unsigned long max_autoclose_max =
  42         (MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
  43         ? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
  44
  45 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
  46                                  void *buffer, size_t *lenp, loff_t *ppos);
  47 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
  48                                 void *buffer, size_t *lenp, loff_t *ppos);
  49 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write, void *buffer,
  50                                 size_t *lenp, loff_t *ppos);
  51 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
  52                                    void *buffer, size_t *lenp, loff_t *ppos);
  53 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
  54                              void *buffer, size_t *lenp, loff_t *ppos);
  55
  56 static struct ctl_table sctp_table[] = {
  57         {
  58                 .procname       = "sctp_mem",
  59                 .data           = &sysctl_sctp_mem,
  60                 .maxlen         = sizeof(sysctl_sctp_mem),
  61                 .mode           = 0644,
  62                 .proc_handler   = proc_doulongvec_minmax
  63         },
  64         {
  65                 .procname       = "sctp_rmem",
  66                 .data           = &sysctl_sctp_rmem,
  67                 .maxlen         = sizeof(sysctl_sctp_rmem),
  68                 .mode           = 0644,
  69                 .proc_handler   = proc_dointvec,
  70         },
  71         {
  72                 .procname       = "sctp_wmem",
  73                 .data           = &sysctl_sctp_wmem,
  74                 .maxlen         = sizeof(sysctl_sctp_wmem),
  75                 .mode           = 0644,
  76                 .proc_handler   = proc_dointvec,
  77         },
  78
  79         { /* sentinel */ }
  80 };
  81
  82 static struct ctl_table sctp_net_table[] = {
  83         {
  84                 .procname       = "rto_initial",
  85                 .data           = &init_net.sctp.rto_initial,
  86                 .maxlen         = sizeof(unsigned int),
  87                 .mode           = 0644,
  88                 .proc_handler   = proc_dointvec_minmax,
  89                 .extra1         = SYSCTL_ONE,
  90                 .extra2         = &timer_max
  91         },
  92         {
  93                 .procname       = "rto_min",
  94                 .data           = &init_net.sctp.rto_min,
  95                 .maxlen         = sizeof(unsigned int),
  96                 .mode           = 0644,
  97                 .proc_handler   = proc_sctp_do_rto_min,
  98                 .extra1         = SYSCTL_ONE,
  99                 .extra2         = &init_net.sctp.rto_max
 100         },
 101         {
 102                 .procname       = "rto_max",
 103                 .data           = &init_net.sctp.rto_max,
 104                 .maxlen         = sizeof(unsigned int),
 105                 .mode           = 0644,
 106                 .proc_handler   = proc_sctp_do_rto_max,
 107                 .extra1         = &init_net.sctp.rto_min,
 108                 .extra2         = &timer_max
 109         },
 110         {
 111                 .procname       = "rto_alpha_exp_divisor",
 112                 .data           = &init_net.sctp.rto_alpha,
 113                 .maxlen         = sizeof(int),
 114                 .mode           = 0644,
 115                 .proc_handler   = proc_sctp_do_alpha_beta,
 116                 .extra1         = &rto_alpha_min,
 117                 .extra2         = &rto_alpha_max,
 118         },
 119         {
 120                 .procname       = "rto_beta_exp_divisor",
 121                 .data           = &init_net.sctp.rto_beta,
 122                 .maxlen         = sizeof(int),
 123                 .mode           = 0644,
 124                 .proc_handler   = proc_sctp_do_alpha_beta,
 125                 .extra1         = &rto_beta_min,
 126                 .extra2         = &rto_beta_max,
 127         },
 128         {
 129                 .procname       = "max_burst",
 130                 .data           = &init_net.sctp.max_burst,
 131                 .maxlen         = sizeof(int),
 132                 .mode           = 0644,
 133                 .proc_handler   = proc_dointvec_minmax,
 134                 .extra1         = SYSCTL_ZERO,
 135                 .extra2         = SYSCTL_INT_MAX,
 136         },
 137         {
 138                 .procname       = "cookie_preserve_enable",
 139                 .data           = &init_net.sctp.cookie_preserve_enable,
 140                 .maxlen         = sizeof(int),
 141                 .mode           = 0644,
 142                 .proc_handler   = proc_dointvec,
 143         },
 144         {
 145                 .procname       = "cookie_hmac_alg",
 146                 .data           = &init_net.sctp.sctp_hmac_alg,
 147                 .maxlen         = 8,
 148                 .mode           = 0644,
 149                 .proc_handler   = proc_sctp_do_hmac_alg,
 150         },
 151         {
 152                 .procname       = "valid_cookie_life",
 153                 .data           = &init_net.sctp.valid_cookie_life,
 154                 .maxlen         = sizeof(unsigned int),
 155                 .mode           = 0644,
 156                 .proc_handler   = proc_dointvec_minmax,
 157                 .extra1         = SYSCTL_ONE,
 158                 .extra2         = &timer_max
 159         },
 160         {
 161                 .procname       = "sack_timeout",
 162                 .data           = &init_net.sctp.sack_timeout,
 163                 .maxlen         = sizeof(int),
 164                 .mode           = 0644,
 165                 .proc_handler   = proc_dointvec_minmax,
 166                 .extra1         = &sack_timer_min,
 167                 .extra2         = &sack_timer_max,
 168         },
 169         {
 170                 .procname       = "hb_interval",
 171                 .data           = &init_net.sctp.hb_interval,
 172                 .maxlen         = sizeof(unsigned int),
 173                 .mode           = 0644,
 174                 .proc_handler   = proc_dointvec_minmax,
 175                 .extra1         = SYSCTL_ONE,
 176                 .extra2         = &timer_max
 177         },
 178         {
 179                 .procname       = "association_max_retrans",
 180                 .data           = &init_net.sctp.max_retrans_association,
 181                 .maxlen         = sizeof(int),
 182                 .mode           = 0644,
 183                 .proc_handler   = proc_dointvec_minmax,
 184                 .extra1         = SYSCTL_ONE,
 185                 .extra2         = SYSCTL_INT_MAX,
 186         },
 187         {
 188                 .procname       = "path_max_retrans",
 189                 .data           = &init_net.sctp.max_retrans_path,
 190                 .maxlen         = sizeof(int),
 191                 .mode           = 0644,
 192                 .proc_handler   = proc_dointvec_minmax,
 193                 .extra1         = SYSCTL_ONE,
 194                 .extra2         = SYSCTL_INT_MAX,
 195         },
 196         {
 197                 .procname       = "max_init_retransmits",
 198                 .data           = &init_net.sctp.max_retrans_init,
 199                 .maxlen         = sizeof(int),
 200                 .mode           = 0644,
 201                 .proc_handler   = proc_dointvec_minmax,
 202                 .extra1         = SYSCTL_ONE,
 203                 .extra2         = SYSCTL_INT_MAX,
 204         },
 205         {
 206                 .procname       = "pf_retrans",
 207                 .data           = &init_net.sctp.pf_retrans,
 208                 .maxlen         = sizeof(int),
 209                 .mode           = 0644,
 210                 .proc_handler   = proc_dointvec_minmax,
 211                 .extra1         = SYSCTL_ZERO,
 212                 .extra2         = &init_net.sctp.ps_retrans,
 213         },
 214         {
 215                 .procname       = "ps_retrans",
 216                 .data           = &init_net.sctp.ps_retrans,
 217                 .maxlen         = sizeof(int),
 218                 .mode           = 0644,
 219                 .proc_handler   = proc_dointvec_minmax,
 220                 .extra1         = &init_net.sctp.pf_retrans,
 221                 .extra2         = &ps_retrans_max,
 222         },
 223         {
 224                 .procname       = "sndbuf_policy",
 225                 .data           = &init_net.sctp.sndbuf_policy,
 226                 .maxlen         = sizeof(int),
 227                 .mode           = 0644,
 228                 .proc_handler   = proc_dointvec,
 229         },
 230         {
 231                 .procname       = "rcvbuf_policy",
 232                 .data           = &init_net.sctp.rcvbuf_policy,
 233                 .maxlen         = sizeof(int),
 234                 .mode           = 0644,
 235                 .proc_handler   = proc_dointvec,
 236         },
 237         {
 238                 .procname       = "default_auto_asconf",
 239                 .data           = &init_net.sctp.default_auto_asconf,
 240                 .maxlen         = sizeof(int),
 241                 .mode           = 0644,
 242                 .proc_handler   = proc_dointvec,
 243         },
 244         {
 245                 .procname       = "addip_enable",
 246                 .data           = &init_net.sctp.addip_enable,
 247                 .maxlen         = sizeof(int),
 248                 .mode           = 0644,
 249                 .proc_handler   = proc_dointvec,
 250         },
 251         {
 252                 .procname       = "addip_noauth_enable",
 253                 .data           = &init_net.sctp.addip_noauth,
 254                 .maxlen         = sizeof(int),
 255                 .mode           = 0644,
 256                 .proc_handler   = proc_dointvec,
 257         },
 258         {
 259                 .procname       = "prsctp_enable",
 260                 .data           = &init_net.sctp.prsctp_enable,
 261                 .maxlen         = sizeof(int),
 262                 .mode           = 0644,
 263                 .proc_handler   = proc_dointvec,
 264         },
 265         {
 266                 .procname       = "reconf_enable",
 267                 .data           = &init_net.sctp.reconf_enable,
 268                 .maxlen         = sizeof(int),
 269                 .mode           = 0644,
 270                 .proc_handler   = proc_dointvec,
 271         },
 272         {
 273                 .procname       = "auth_enable",
 274                 .data           = &init_net.sctp.auth_enable,
 275                 .maxlen         = sizeof(int),
 276                 .mode           = 0644,
 277                 .proc_handler   = proc_sctp_do_auth,
 278         },
 279         {
 280                 .procname       = "intl_enable",
 281                 .data           = &init_net.sctp.intl_enable,
 282                 .maxlen         = sizeof(int),
 283                 .mode           = 0644,
 284                 .proc_handler   = proc_dointvec,
 285         },
 286         {
 287                 .procname       = "ecn_enable",
 288                 .data           = &init_net.sctp.ecn_enable,
 289                 .maxlen         = sizeof(int),
 290                 .mode           = 0644,
 291                 .proc_handler   = proc_dointvec,
 292         },
 293         {
 294                 .procname       = "addr_scope_policy",
 295                 .data           = &init_net.sctp.scope_policy,
 296                 .maxlen         = sizeof(int),
 297                 .mode           = 0644,
 298                 .proc_handler   = proc_dointvec_minmax,
 299                 .extra1         = SYSCTL_ZERO,
 300                 .extra2         = &addr_scope_max,
 301         },
 302         {
 303                 .procname       = "rwnd_update_shift",
 304                 .data           = &init_net.sctp.rwnd_upd_shift,
 305                 .maxlen         = sizeof(int),
 306                 .mode           = 0644,
 307                 .proc_handler   = &proc_dointvec_minmax,
 308                 .extra1         = SYSCTL_ONE,
 309                 .extra2         = &rwnd_scale_max,
 310         },
 311         {
 312                 .procname       = "max_autoclose",
 313                 .data           = &init_net.sctp.max_autoclose,
 314                 .maxlen         = sizeof(unsigned long),
 315                 .mode           = 0644,
 316                 .proc_handler   = &proc_doulongvec_minmax,
 317                 .extra1         = &max_autoclose_min,
 318                 .extra2         = &max_autoclose_max,
 319         },
 320         {
 321                 .procname       = "pf_enable",
 322                 .data           = &init_net.sctp.pf_enable,
 323                 .maxlen         = sizeof(int),
 324                 .mode           = 0644,
 325                 .proc_handler   = proc_dointvec,
 326         },
 327         {
 328                 .procname       = "pf_expose",
 329                 .data           = &init_net.sctp.pf_expose,
 330                 .maxlen         = sizeof(int),
 331                 .mode           = 0644,
 332                 .proc_handler   = proc_dointvec_minmax,
 333                 .extra1         = SYSCTL_ZERO,
 334                 .extra2         = &pf_expose_max,
 335         },
 336
 337         { /* sentinel */ }
 338 };
 339
 340 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
 341                                  void *buffer, size_t *lenp, loff_t *ppos)
 342 {
 343         struct net *net = current->nsproxy->net_ns;
 344         struct ctl_table tbl;
 345         bool changed = false;
 346         char *none = "none";
 347         char tmp[8] = {0};
 348         int ret;
 349
 350         memset(&tbl, 0, sizeof(struct ctl_table));
 351
 352         if (write) {
 353                 tbl.data = tmp;
 354                 tbl.maxlen = sizeof(tmp);
 355         } else {
 356                 tbl.data = net->sctp.sctp_hmac_alg ? : none;
 357                 tbl.maxlen = strlen(tbl.data);
 358         }
 359
 360         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 361         if (write && ret == 0) {
 362 #ifdef CONFIG_CRYPTO_MD5
 363                 if (!strncmp(tmp, "md5", 3)) {
 364                         net->sctp.sctp_hmac_alg = "md5";
 365                         changed = true;
 366                 }
 367 #endif
 368 #ifdef CONFIG_CRYPTO_SHA1
 369                 if (!strncmp(tmp, "sha1", 4)) {
 370                         net->sctp.sctp_hmac_alg = "sha1";
 371                         changed = true;
 372                 }
 373 #endif
 374                 if (!strncmp(tmp, "none", 4)) {
 375                         net->sctp.sctp_hmac_alg = NULL;
 376                         changed = true;
 377                 }
 378                 if (!changed)
 379                         ret = -EINVAL;
 380         }
 381
 382         return ret;
 383 }
 384
 385 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
 386                                 void *buffer, size_t *lenp, loff_t *ppos)
 387 {
 388         struct net *net = current->nsproxy->net_ns;
 389         unsigned int min = *(unsigned int *) ctl->extra1;
 390         unsigned int max = *(unsigned int *) ctl->extra2;
 391         struct ctl_table tbl;
 392         int ret, new_value;
 393
 394         memset(&tbl, 0, sizeof(struct ctl_table));
 395         tbl.maxlen = sizeof(unsigned int);
 396
 397         if (write)
 398                 tbl.data = &new_value;
 399         else
 400                 tbl.data = &net->sctp.rto_min;
 401
 402         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 403         if (write && ret == 0) {
 404                 if (new_value > max || new_value < min)
 405                         return -EINVAL;
 406
 407                 net->sctp.rto_min = new_value;
 408         }
 409
 410         return ret;
 411 }
 412
 413 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
 414                                 void *buffer, size_t *lenp, loff_t *ppos)
 415 {
 416         struct net *net = current->nsproxy->net_ns;
 417         unsigned int min = *(unsigned int *) ctl->extra1;
 418         unsigned int max = *(unsigned int *) ctl->extra2;
 419         struct ctl_table tbl;
 420         int ret, new_value;
 421
 422         memset(&tbl, 0, sizeof(struct ctl_table));
 423         tbl.maxlen = sizeof(unsigned int);
 424
 425         if (write)
 426                 tbl.data = &new_value;
 427         else
 428                 tbl.data = &net->sctp.rto_max;
 429
 430         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 431         if (write && ret == 0) {
 432                 if (new_value > max || new_value < min)
 433                         return -EINVAL;
 434
 435                 net->sctp.rto_max = new_value;
 436         }
 437
 438         return ret;
 439 }
 440
 441 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
 442                                    void *buffer, size_t *lenp, loff_t *ppos)
 443 {
 444         if (write)
 445                 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
 446                              "suboptimal rtt/srtt estimations!\n");
 447
 448         return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
 449 }
 450
 451 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
 452                              void *buffer, size_t *lenp, loff_t *ppos)
 453 {
 454         struct net *net = current->nsproxy->net_ns;
 455         struct ctl_table tbl;
 456         int new_value, ret;
 457
 458         memset(&tbl, 0, sizeof(struct ctl_table));
 459         tbl.maxlen = sizeof(unsigned int);
 460
 461         if (write)
 462                 tbl.data = &new_value;
 463         else
 464                 tbl.data = &net->sctp.auth_enable;
 465
 466         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 467         if (write && ret == 0) {
 468                 struct sock *sk = net->sctp.ctl_sock;
 469
 470                 net->sctp.auth_enable = new_value;
 471                 /* Update the value in the control socket */
 472                 lock_sock(sk);
 473                 sctp_sk(sk)->ep->auth_enable = new_value;
 474                 release_sock(sk);
 475         }
 476
 477         return ret;
 478 }
 479
 480 int sctp_sysctl_net_register(struct net *net)
 481 {
 482         struct ctl_table *table;
 483         int i;
 484
 485         table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
 486         if (!table)
 487                 return -ENOMEM;
 488
 489         for (i = 0; table[i].data; i++)
 490                 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
 491
 492         net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
 493         if (net->sctp.sysctl_header == NULL) {
 494                 kfree(table);
 495                 return -ENOMEM;
 496         }
 497         return 0;
 498 }
 499
 500 void sctp_sysctl_net_unregister(struct net *net)
 501 {
 502         struct ctl_table *table;
 503
 504         table = net->sctp.sysctl_header->ctl_table_arg;
 505         unregister_net_sysctl_table(net->sctp.sysctl_header);
 506         kfree(table);
 507 }
 508
 509 static struct ctl_table_header *sctp_sysctl_header;
 510
 511 /* Sysctl registration.  */
 512 void sctp_sysctl_register(void)
 513 {
 514         sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
 515 }
 516
 517 /* Sysctl deregistration.  */
 518 void sctp_sysctl_unregister(void)
 519 {
 520         unregister_net_sysctl_table(sctp_sysctl_header);
 521 }