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 static int udp_port_max = 65535;
  40
  41 static unsigned long max_autoclose_min = 0;
  42 static unsigned long max_autoclose_max =
  43         (MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
  44         ? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
  45
  46 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
  47                                  void *buffer, size_t *lenp, loff_t *ppos);
  48 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
  49                                 void *buffer, size_t *lenp, loff_t *ppos);
  50 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write, void *buffer,
  51                                 size_t *lenp, loff_t *ppos);
  52 static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write, void *buffer,
  53                                  size_t *lenp, loff_t *ppos);
  54 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
  55                                    void *buffer, size_t *lenp, loff_t *ppos);
  56 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
  57                              void *buffer, size_t *lenp, 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         = &init_net.sctp.ps_retrans,
 216         },
 217         {
 218                 .procname       = "ps_retrans",
 219                 .data           = &init_net.sctp.ps_retrans,
 220                 .maxlen         = sizeof(int),
 221                 .mode           = 0644,
 222                 .proc_handler   = proc_dointvec_minmax,
 223                 .extra1         = &init_net.sctp.pf_retrans,
 224                 .extra2         = &ps_retrans_max,
 225         },
 226         {
 227                 .procname       = "sndbuf_policy",
 228                 .data           = &init_net.sctp.sndbuf_policy,
 229                 .maxlen         = sizeof(int),
 230                 .mode           = 0644,
 231                 .proc_handler   = proc_dointvec,
 232         },
 233         {
 234                 .procname       = "rcvbuf_policy",
 235                 .data           = &init_net.sctp.rcvbuf_policy,
 236                 .maxlen         = sizeof(int),
 237                 .mode           = 0644,
 238                 .proc_handler   = proc_dointvec,
 239         },
 240         {
 241                 .procname       = "default_auto_asconf",
 242                 .data           = &init_net.sctp.default_auto_asconf,
 243                 .maxlen         = sizeof(int),
 244                 .mode           = 0644,
 245                 .proc_handler   = proc_dointvec,
 246         },
 247         {
 248                 .procname       = "addip_enable",
 249                 .data           = &init_net.sctp.addip_enable,
 250                 .maxlen         = sizeof(int),
 251                 .mode           = 0644,
 252                 .proc_handler   = proc_dointvec,
 253         },
 254         {
 255                 .procname       = "addip_noauth_enable",
 256                 .data           = &init_net.sctp.addip_noauth,
 257                 .maxlen         = sizeof(int),
 258                 .mode           = 0644,
 259                 .proc_handler   = proc_dointvec,
 260         },
 261         {
 262                 .procname       = "prsctp_enable",
 263                 .data           = &init_net.sctp.prsctp_enable,
 264                 .maxlen         = sizeof(int),
 265                 .mode           = 0644,
 266                 .proc_handler   = proc_dointvec,
 267         },
 268         {
 269                 .procname       = "reconf_enable",
 270                 .data           = &init_net.sctp.reconf_enable,
 271                 .maxlen         = sizeof(int),
 272                 .mode           = 0644,
 273                 .proc_handler   = proc_dointvec,
 274         },
 275         {
 276                 .procname       = "auth_enable",
 277                 .data           = &init_net.sctp.auth_enable,
 278                 .maxlen         = sizeof(int),
 279                 .mode           = 0644,
 280                 .proc_handler   = proc_sctp_do_auth,
 281         },
 282         {
 283                 .procname       = "intl_enable",
 284                 .data           = &init_net.sctp.intl_enable,
 285                 .maxlen         = sizeof(int),
 286                 .mode           = 0644,
 287                 .proc_handler   = proc_dointvec,
 288         },
 289         {
 290                 .procname       = "ecn_enable",
 291                 .data           = &init_net.sctp.ecn_enable,
 292                 .maxlen         = sizeof(int),
 293                 .mode           = 0644,
 294                 .proc_handler   = proc_dointvec,
 295         },
 296         {
 297                 .procname       = "udp_port",
 298                 .data           = &init_net.sctp.udp_port,
 299                 .maxlen         = sizeof(int),
 300                 .mode           = 0644,
 301                 .proc_handler   = proc_sctp_do_udp_port,
 302                 .extra1         = SYSCTL_ZERO,
 303                 .extra2         = &udp_port_max,
 304         },
 305         {
 306                 .procname       = "encap_port",
 307                 .data           = &init_net.sctp.encap_port,
 308                 .maxlen         = sizeof(int),
 309                 .mode           = 0644,
 310                 .proc_handler   = proc_dointvec,
 311                 .extra1         = SYSCTL_ZERO,
 312                 .extra2         = &udp_port_max,
 313         },
 314         {
 315                 .procname       = "addr_scope_policy",
 316                 .data           = &init_net.sctp.scope_policy,
 317                 .maxlen         = sizeof(int),
 318                 .mode           = 0644,
 319                 .proc_handler   = proc_dointvec_minmax,
 320                 .extra1         = SYSCTL_ZERO,
 321                 .extra2         = &addr_scope_max,
 322         },
 323         {
 324                 .procname       = "rwnd_update_shift",
 325                 .data           = &init_net.sctp.rwnd_upd_shift,
 326                 .maxlen         = sizeof(int),
 327                 .mode           = 0644,
 328                 .proc_handler   = &proc_dointvec_minmax,
 329                 .extra1         = SYSCTL_ONE,
 330                 .extra2         = &rwnd_scale_max,
 331         },
 332         {
 333                 .procname       = "max_autoclose",
 334                 .data           = &init_net.sctp.max_autoclose,
 335                 .maxlen         = sizeof(unsigned long),
 336                 .mode           = 0644,
 337                 .proc_handler   = &proc_doulongvec_minmax,
 338                 .extra1         = &max_autoclose_min,
 339                 .extra2         = &max_autoclose_max,
 340         },
 341         {
 342                 .procname       = "pf_enable",
 343                 .data           = &init_net.sctp.pf_enable,
 344                 .maxlen         = sizeof(int),
 345                 .mode           = 0644,
 346                 .proc_handler   = proc_dointvec,
 347         },
 348         {
 349                 .procname       = "pf_expose",
 350                 .data           = &init_net.sctp.pf_expose,
 351                 .maxlen         = sizeof(int),
 352                 .mode           = 0644,
 353                 .proc_handler   = proc_dointvec_minmax,
 354                 .extra1         = SYSCTL_ZERO,
 355                 .extra2         = &pf_expose_max,
 356         },
 357
 358         { /* sentinel */ }
 359 };
 360
 361 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
 362                                  void *buffer, size_t *lenp, loff_t *ppos)
 363 {
 364         struct net *net = current->nsproxy->net_ns;
 365         struct ctl_table tbl;
 366         bool changed = false;
 367         char *none = "none";
 368         char tmp[8] = {0};
 369         int ret;
 370
 371         memset(&tbl, 0, sizeof(struct ctl_table));
 372
 373         if (write) {
 374                 tbl.data = tmp;
 375                 tbl.maxlen = sizeof(tmp);
 376         } else {
 377                 tbl.data = net->sctp.sctp_hmac_alg ? : none;
 378                 tbl.maxlen = strlen(tbl.data);
 379         }
 380
 381         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 382         if (write && ret == 0) {
 383 #ifdef CONFIG_CRYPTO_MD5
 384                 if (!strncmp(tmp, "md5", 3)) {
 385                         net->sctp.sctp_hmac_alg = "md5";
 386                         changed = true;
 387                 }
 388 #endif
 389 #ifdef CONFIG_CRYPTO_SHA1
 390                 if (!strncmp(tmp, "sha1", 4)) {
 391                         net->sctp.sctp_hmac_alg = "sha1";
 392                         changed = true;
 393                 }
 394 #endif
 395                 if (!strncmp(tmp, "none", 4)) {
 396                         net->sctp.sctp_hmac_alg = NULL;
 397                         changed = true;
 398                 }
 399                 if (!changed)
 400                         ret = -EINVAL;
 401         }
 402
 403         return ret;
 404 }
 405
 406 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
 407                                 void *buffer, size_t *lenp, loff_t *ppos)
 408 {
 409         struct net *net = current->nsproxy->net_ns;
 410         unsigned int min = *(unsigned int *) ctl->extra1;
 411         unsigned int max = *(unsigned int *) ctl->extra2;
 412         struct ctl_table tbl;
 413         int ret, new_value;
 414
 415         memset(&tbl, 0, sizeof(struct ctl_table));
 416         tbl.maxlen = sizeof(unsigned int);
 417
 418         if (write)
 419                 tbl.data = &new_value;
 420         else
 421                 tbl.data = &net->sctp.rto_min;
 422
 423         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 424         if (write && ret == 0) {
 425                 if (new_value > max || new_value < min)
 426                         return -EINVAL;
 427
 428                 net->sctp.rto_min = new_value;
 429         }
 430
 431         return ret;
 432 }
 433
 434 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
 435                                 void *buffer, size_t *lenp, loff_t *ppos)
 436 {
 437         struct net *net = current->nsproxy->net_ns;
 438         unsigned int min = *(unsigned int *) ctl->extra1;
 439         unsigned int max = *(unsigned int *) ctl->extra2;
 440         struct ctl_table tbl;
 441         int ret, new_value;
 442
 443         memset(&tbl, 0, sizeof(struct ctl_table));
 444         tbl.maxlen = sizeof(unsigned int);
 445
 446         if (write)
 447                 tbl.data = &new_value;
 448         else
 449                 tbl.data = &net->sctp.rto_max;
 450
 451         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 452         if (write && ret == 0) {
 453                 if (new_value > max || new_value < min)
 454                         return -EINVAL;
 455
 456                 net->sctp.rto_max = new_value;
 457         }
 458
 459         return ret;
 460 }
 461
 462 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
 463                                    void *buffer, size_t *lenp, loff_t *ppos)
 464 {
 465         if (write)
 466                 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
 467                              "suboptimal rtt/srtt estimations!\n");
 468
 469         return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
 470 }
 471
 472 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
 473                              void *buffer, size_t *lenp, loff_t *ppos)
 474 {
 475         struct net *net = current->nsproxy->net_ns;
 476         struct ctl_table tbl;
 477         int new_value, ret;
 478
 479         memset(&tbl, 0, sizeof(struct ctl_table));
 480         tbl.maxlen = sizeof(unsigned int);
 481
 482         if (write)
 483                 tbl.data = &new_value;
 484         else
 485                 tbl.data = &net->sctp.auth_enable;
 486
 487         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 488         if (write && ret == 0) {
 489                 struct sock *sk = net->sctp.ctl_sock;
 490
 491                 net->sctp.auth_enable = new_value;
 492                 /* Update the value in the control socket */
 493                 lock_sock(sk);
 494                 sctp_sk(sk)->ep->auth_enable = new_value;
 495                 release_sock(sk);
 496         }
 497
 498         return ret;
 499 }
 500
 501 static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write,
 502                                  void *buffer, size_t *lenp, loff_t *ppos)
 503 {
 504         struct net *net = current->nsproxy->net_ns;
 505         unsigned int min = *(unsigned int *)ctl->extra1;
 506         unsigned int max = *(unsigned int *)ctl->extra2;
 507         struct ctl_table tbl;
 508         int ret, new_value;
 509
 510         memset(&tbl, 0, sizeof(struct ctl_table));
 511         tbl.maxlen = sizeof(unsigned int);
 512
 513         if (write)
 514                 tbl.data = &new_value;
 515         else
 516                 tbl.data = &net->sctp.udp_port;
 517
 518         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 519         if (write && ret == 0) {
 520                 struct sock *sk = net->sctp.ctl_sock;
 521
 522                 if (new_value > max || new_value < min)
 523                         return -EINVAL;
 524
 525                 net->sctp.udp_port = new_value;
 526                 sctp_udp_sock_stop(net);
 527                 if (new_value) {
 528                         ret = sctp_udp_sock_start(net);
 529                         if (ret)
 530                                 net->sctp.udp_port = 0;
 531                 }
 532
 533                 /* Update the value in the control socket */
 534                 lock_sock(sk);
 535                 sctp_sk(sk)->udp_port = htons(net->sctp.udp_port);
 536                 release_sock(sk);
 537         }
 538
 539         return ret;
 540 }
 541
 542 int sctp_sysctl_net_register(struct net *net)
 543 {
 544         struct ctl_table *table;
 545         int i;
 546
 547         table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
 548         if (!table)
 549                 return -ENOMEM;
 550
 551         for (i = 0; table[i].data; i++)
 552                 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
 553
 554         net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
 555         if (net->sctp.sysctl_header == NULL) {
 556                 kfree(table);
 557                 return -ENOMEM;
 558         }
 559         return 0;
 560 }
 561
 562 void sctp_sysctl_net_unregister(struct net *net)
 563 {
 564         struct ctl_table *table;
 565
 566         table = net->sctp.sysctl_header->ctl_table_arg;
 567         unregister_net_sysctl_table(net->sctp.sysctl_header);
 568         kfree(table);
 569 }
 570
 571 static struct ctl_table_header *sctp_sysctl_header;
 572
 573 /* Sysctl registration.  */
 574 void sctp_sysctl_register(void)
 575 {
 576         sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
 577 }
 578
 579 /* Sysctl deregistration.  */
 580 void sctp_sysctl_unregister(void)
 581 {
 582         unregister_net_sysctl_table(sctp_sysctl_header);
 583 }