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 __user *buffer, size_t *lenp,
  47                                 loff_t *ppos);
  48 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
  49                                 void __user *buffer, size_t *lenp,
  50                                 loff_t *ppos);
  51 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
  52                                 void __user *buffer, size_t *lenp,
  53                                 loff_t *ppos);
  54 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
  55                                    void __user *buffer, size_t *lenp,
  56                                    loff_t *ppos);
  57 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
  58                              void __user *buffer, size_t *lenp,
  59                              loff_t *ppos);
  60
  61 static struct ctl_table sctp_table[] = {
  62         {
  63                 .procname       = "sctp_mem",
  64                 .data           = &sysctl_sctp_mem,
  65                 .maxlen         = sizeof(sysctl_sctp_mem),
  66                 .mode           = 0644,
  67                 .proc_handler   = proc_doulongvec_minmax
  68         },
  69         {
  70                 .procname       = "sctp_rmem",
  71                 .data           = &sysctl_sctp_rmem,
  72                 .maxlen         = sizeof(sysctl_sctp_rmem),
  73                 .mode           = 0644,
  74                 .proc_handler   = proc_dointvec,
  75         },
  76         {
  77                 .procname       = "sctp_wmem",
  78                 .data           = &sysctl_sctp_wmem,
  79                 .maxlen         = sizeof(sysctl_sctp_wmem),
  80                 .mode           = 0644,
  81                 .proc_handler   = proc_dointvec,
  82         },
  83
  84         { /* sentinel */ }
  85 };
  86
  87 static struct ctl_table sctp_net_table[] = {
  88         {
  89                 .procname       = "rto_initial",
  90                 .data           = &init_net.sctp.rto_initial,
  91                 .maxlen         = sizeof(unsigned int),
  92                 .mode           = 0644,
  93                 .proc_handler   = proc_dointvec_minmax,
  94                 .extra1         = SYSCTL_ONE,
  95                 .extra2         = &timer_max
  96         },
  97         {
  98                 .procname       = "rto_min",
  99                 .data           = &init_net.sctp.rto_min,
 100                 .maxlen         = sizeof(unsigned int),
 101                 .mode           = 0644,
 102                 .proc_handler   = proc_sctp_do_rto_min,
 103                 .extra1         = SYSCTL_ONE,
 104                 .extra2         = &init_net.sctp.rto_max
 105         },
 106         {
 107                 .procname       = "rto_max",
 108                 .data           = &init_net.sctp.rto_max,
 109                 .maxlen         = sizeof(unsigned int),
 110                 .mode           = 0644,
 111                 .proc_handler   = proc_sctp_do_rto_max,
 112                 .extra1         = &init_net.sctp.rto_min,
 113                 .extra2         = &timer_max
 114         },
 115         {
 116                 .procname       = "rto_alpha_exp_divisor",
 117                 .data           = &init_net.sctp.rto_alpha,
 118                 .maxlen         = sizeof(int),
 119                 .mode           = 0644,
 120                 .proc_handler   = proc_sctp_do_alpha_beta,
 121                 .extra1         = &rto_alpha_min,
 122                 .extra2         = &rto_alpha_max,
 123         },
 124         {
 125                 .procname       = "rto_beta_exp_divisor",
 126                 .data           = &init_net.sctp.rto_beta,
 127                 .maxlen         = sizeof(int),
 128                 .mode           = 0644,
 129                 .proc_handler   = proc_sctp_do_alpha_beta,
 130                 .extra1         = &rto_beta_min,
 131                 .extra2         = &rto_beta_max,
 132         },
 133         {
 134                 .procname       = "max_burst",
 135                 .data           = &init_net.sctp.max_burst,
 136                 .maxlen         = sizeof(int),
 137                 .mode           = 0644,
 138                 .proc_handler   = proc_dointvec_minmax,
 139                 .extra1         = SYSCTL_ZERO,
 140                 .extra2         = SYSCTL_INT_MAX,
 141         },
 142         {
 143                 .procname       = "cookie_preserve_enable",
 144                 .data           = &init_net.sctp.cookie_preserve_enable,
 145                 .maxlen         = sizeof(int),
 146                 .mode           = 0644,
 147                 .proc_handler   = proc_dointvec,
 148         },
 149         {
 150                 .procname       = "cookie_hmac_alg",
 151                 .data           = &init_net.sctp.sctp_hmac_alg,
 152                 .maxlen         = 8,
 153                 .mode           = 0644,
 154                 .proc_handler   = proc_sctp_do_hmac_alg,
 155         },
 156         {
 157                 .procname       = "valid_cookie_life",
 158                 .data           = &init_net.sctp.valid_cookie_life,
 159                 .maxlen         = sizeof(unsigned int),
 160                 .mode           = 0644,
 161                 .proc_handler   = proc_dointvec_minmax,
 162                 .extra1         = SYSCTL_ONE,
 163                 .extra2         = &timer_max
 164         },
 165         {
 166                 .procname       = "sack_timeout",
 167                 .data           = &init_net.sctp.sack_timeout,
 168                 .maxlen         = sizeof(int),
 169                 .mode           = 0644,
 170                 .proc_handler   = proc_dointvec_minmax,
 171                 .extra1         = &sack_timer_min,
 172                 .extra2         = &sack_timer_max,
 173         },
 174         {
 175                 .procname       = "hb_interval",
 176                 .data           = &init_net.sctp.hb_interval,
 177                 .maxlen         = sizeof(unsigned int),
 178                 .mode           = 0644,
 179                 .proc_handler   = proc_dointvec_minmax,
 180                 .extra1         = SYSCTL_ONE,
 181                 .extra2         = &timer_max
 182         },
 183         {
 184                 .procname       = "association_max_retrans",
 185                 .data           = &init_net.sctp.max_retrans_association,
 186                 .maxlen         = sizeof(int),
 187                 .mode           = 0644,
 188                 .proc_handler   = proc_dointvec_minmax,
 189                 .extra1         = SYSCTL_ONE,
 190                 .extra2         = SYSCTL_INT_MAX,
 191         },
 192         {
 193                 .procname       = "path_max_retrans",
 194                 .data           = &init_net.sctp.max_retrans_path,
 195                 .maxlen         = sizeof(int),
 196                 .mode           = 0644,
 197                 .proc_handler   = proc_dointvec_minmax,
 198                 .extra1         = SYSCTL_ONE,
 199                 .extra2         = SYSCTL_INT_MAX,
 200         },
 201         {
 202                 .procname       = "max_init_retransmits",
 203                 .data           = &init_net.sctp.max_retrans_init,
 204                 .maxlen         = sizeof(int),
 205                 .mode           = 0644,
 206                 .proc_handler   = proc_dointvec_minmax,
 207                 .extra1         = SYSCTL_ONE,
 208                 .extra2         = SYSCTL_INT_MAX,
 209         },
 210         {
 211                 .procname       = "pf_retrans",
 212                 .data           = &init_net.sctp.pf_retrans,
 213                 .maxlen         = sizeof(int),
 214                 .mode           = 0644,
 215                 .proc_handler   = proc_dointvec_minmax,
 216                 .extra1         = SYSCTL_ZERO,
 217                 .extra2         = &init_net.sctp.ps_retrans,
 218         },
 219         {
 220                 .procname       = "ps_retrans",
 221                 .data           = &init_net.sctp.ps_retrans,
 222                 .maxlen         = sizeof(int),
 223                 .mode           = 0644,
 224                 .proc_handler   = proc_dointvec_minmax,
 225                 .extra1         = &init_net.sctp.pf_retrans,
 226                 .extra2         = &ps_retrans_max,
 227         },
 228         {
 229                 .procname       = "sndbuf_policy",
 230                 .data           = &init_net.sctp.sndbuf_policy,
 231                 .maxlen         = sizeof(int),
 232                 .mode           = 0644,
 233                 .proc_handler   = proc_dointvec,
 234         },
 235         {
 236                 .procname       = "rcvbuf_policy",
 237                 .data           = &init_net.sctp.rcvbuf_policy,
 238                 .maxlen         = sizeof(int),
 239                 .mode           = 0644,
 240                 .proc_handler   = proc_dointvec,
 241         },
 242         {
 243                 .procname       = "default_auto_asconf",
 244                 .data           = &init_net.sctp.default_auto_asconf,
 245                 .maxlen         = sizeof(int),
 246                 .mode           = 0644,
 247                 .proc_handler   = proc_dointvec,
 248         },
 249         {
 250                 .procname       = "addip_enable",
 251                 .data           = &init_net.sctp.addip_enable,
 252                 .maxlen         = sizeof(int),
 253                 .mode           = 0644,
 254                 .proc_handler   = proc_dointvec,
 255         },
 256         {
 257                 .procname       = "addip_noauth_enable",
 258                 .data           = &init_net.sctp.addip_noauth,
 259                 .maxlen         = sizeof(int),
 260                 .mode           = 0644,
 261                 .proc_handler   = proc_dointvec,
 262         },
 263         {
 264                 .procname       = "prsctp_enable",
 265                 .data           = &init_net.sctp.prsctp_enable,
 266                 .maxlen         = sizeof(int),
 267                 .mode           = 0644,
 268                 .proc_handler   = proc_dointvec,
 269         },
 270         {
 271                 .procname       = "reconf_enable",
 272                 .data           = &init_net.sctp.reconf_enable,
 273                 .maxlen         = sizeof(int),
 274                 .mode           = 0644,
 275                 .proc_handler   = proc_dointvec,
 276         },
 277         {
 278                 .procname       = "auth_enable",
 279                 .data           = &init_net.sctp.auth_enable,
 280                 .maxlen         = sizeof(int),
 281                 .mode           = 0644,
 282                 .proc_handler   = proc_sctp_do_auth,
 283         },
 284         {
 285                 .procname       = "intl_enable",
 286                 .data           = &init_net.sctp.intl_enable,
 287                 .maxlen         = sizeof(int),
 288                 .mode           = 0644,
 289                 .proc_handler   = proc_dointvec,
 290         },
 291         {
 292                 .procname       = "ecn_enable",
 293                 .data           = &init_net.sctp.ecn_enable,
 294                 .maxlen         = sizeof(int),
 295                 .mode           = 0644,
 296                 .proc_handler   = proc_dointvec,
 297         },
 298         {
 299                 .procname       = "addr_scope_policy",
 300                 .data           = &init_net.sctp.scope_policy,
 301                 .maxlen         = sizeof(int),
 302                 .mode           = 0644,
 303                 .proc_handler   = proc_dointvec_minmax,
 304                 .extra1         = SYSCTL_ZERO,
 305                 .extra2         = &addr_scope_max,
 306         },
 307         {
 308                 .procname       = "rwnd_update_shift",
 309                 .data           = &init_net.sctp.rwnd_upd_shift,
 310                 .maxlen         = sizeof(int),
 311                 .mode           = 0644,
 312                 .proc_handler   = &proc_dointvec_minmax,
 313                 .extra1         = SYSCTL_ONE,
 314                 .extra2         = &rwnd_scale_max,
 315         },
 316         {
 317                 .procname       = "max_autoclose",
 318                 .data           = &init_net.sctp.max_autoclose,
 319                 .maxlen         = sizeof(unsigned long),
 320                 .mode           = 0644,
 321                 .proc_handler   = &proc_doulongvec_minmax,
 322                 .extra1         = &max_autoclose_min,
 323                 .extra2         = &max_autoclose_max,
 324         },
 325         {
 326                 .procname       = "pf_enable",
 327                 .data           = &init_net.sctp.pf_enable,
 328                 .maxlen         = sizeof(int),
 329                 .mode           = 0644,
 330                 .proc_handler   = proc_dointvec,
 331         },
 332         {
 333                 .procname       = "pf_expose",
 334                 .data           = &init_net.sctp.pf_expose,
 335                 .maxlen         = sizeof(int),
 336                 .mode           = 0644,
 337                 .proc_handler   = proc_dointvec_minmax,
 338                 .extra1         = SYSCTL_ZERO,
 339                 .extra2         = &pf_expose_max,
 340         },
 341
 342         { /* sentinel */ }
 343 };
 344
 345 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
 346                                 void __user *buffer, size_t *lenp,
 347                                 loff_t *ppos)
 348 {
 349         struct net *net = current->nsproxy->net_ns;
 350         struct ctl_table tbl;
 351         bool changed = false;
 352         char *none = "none";
 353         char tmp[8] = {0};
 354         int ret;
 355
 356         memset(&tbl, 0, sizeof(struct ctl_table));
 357
 358         if (write) {
 359                 tbl.data = tmp;
 360                 tbl.maxlen = sizeof(tmp);
 361         } else {
 362                 tbl.data = net->sctp.sctp_hmac_alg ? : none;
 363                 tbl.maxlen = strlen(tbl.data);
 364         }
 365
 366         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 367         if (write && ret == 0) {
 368 #ifdef CONFIG_CRYPTO_MD5
 369                 if (!strncmp(tmp, "md5", 3)) {
 370                         net->sctp.sctp_hmac_alg = "md5";
 371                         changed = true;
 372                 }
 373 #endif
 374 #ifdef CONFIG_CRYPTO_SHA1
 375                 if (!strncmp(tmp, "sha1", 4)) {
 376                         net->sctp.sctp_hmac_alg = "sha1";
 377                         changed = true;
 378                 }
 379 #endif
 380                 if (!strncmp(tmp, "none", 4)) {
 381                         net->sctp.sctp_hmac_alg = NULL;
 382                         changed = true;
 383                 }
 384                 if (!changed)
 385                         ret = -EINVAL;
 386         }
 387
 388         return ret;
 389 }
 390
 391 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
 392                                 void __user *buffer, size_t *lenp,
 393                                 loff_t *ppos)
 394 {
 395         struct net *net = current->nsproxy->net_ns;
 396         unsigned int min = *(unsigned int *) ctl->extra1;
 397         unsigned int max = *(unsigned int *) ctl->extra2;
 398         struct ctl_table tbl;
 399         int ret, new_value;
 400
 401         memset(&tbl, 0, sizeof(struct ctl_table));
 402         tbl.maxlen = sizeof(unsigned int);
 403
 404         if (write)
 405                 tbl.data = &new_value;
 406         else
 407                 tbl.data = &net->sctp.rto_min;
 408
 409         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 410         if (write && ret == 0) {
 411                 if (new_value > max || new_value < min)
 412                         return -EINVAL;
 413
 414                 net->sctp.rto_min = new_value;
 415         }
 416
 417         return ret;
 418 }
 419
 420 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
 421                                 void __user *buffer, size_t *lenp,
 422                                 loff_t *ppos)
 423 {
 424         struct net *net = current->nsproxy->net_ns;
 425         unsigned int min = *(unsigned int *) ctl->extra1;
 426         unsigned int max = *(unsigned int *) ctl->extra2;
 427         struct ctl_table tbl;
 428         int ret, new_value;
 429
 430         memset(&tbl, 0, sizeof(struct ctl_table));
 431         tbl.maxlen = sizeof(unsigned int);
 432
 433         if (write)
 434                 tbl.data = &new_value;
 435         else
 436                 tbl.data = &net->sctp.rto_max;
 437
 438         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 439         if (write && ret == 0) {
 440                 if (new_value > max || new_value < min)
 441                         return -EINVAL;
 442
 443                 net->sctp.rto_max = new_value;
 444         }
 445
 446         return ret;
 447 }
 448
 449 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
 450                                    void __user *buffer, size_t *lenp,
 451                                    loff_t *ppos)
 452 {
 453         if (write)
 454                 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
 455                              "suboptimal rtt/srtt estimations!\n");
 456
 457         return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
 458 }
 459
 460 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
 461                              void __user *buffer, size_t *lenp,
 462                              loff_t *ppos)
 463 {
 464         struct net *net = current->nsproxy->net_ns;
 465         struct ctl_table tbl;
 466         int new_value, ret;
 467
 468         memset(&tbl, 0, sizeof(struct ctl_table));
 469         tbl.maxlen = sizeof(unsigned int);
 470
 471         if (write)
 472                 tbl.data = &new_value;
 473         else
 474                 tbl.data = &net->sctp.auth_enable;
 475
 476         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 477         if (write && ret == 0) {
 478                 struct sock *sk = net->sctp.ctl_sock;
 479
 480                 net->sctp.auth_enable = new_value;
 481                 /* Update the value in the control socket */
 482                 lock_sock(sk);
 483                 sctp_sk(sk)->ep->auth_enable = new_value;
 484                 release_sock(sk);
 485         }
 486
 487         return ret;
 488 }
 489
 490 int sctp_sysctl_net_register(struct net *net)
 491 {
 492         struct ctl_table *table;
 493         int i;
 494
 495         table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
 496         if (!table)
 497                 return -ENOMEM;
 498
 499         for (i = 0; table[i].data; i++)
 500                 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
 501
 502         net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
 503         if (net->sctp.sysctl_header == NULL) {
 504                 kfree(table);
 505                 return -ENOMEM;
 506         }
 507         return 0;
 508 }
 509
 510 void sctp_sysctl_net_unregister(struct net *net)
 511 {
 512         struct ctl_table *table;
 513
 514         table = net->sctp.sysctl_header->ctl_table_arg;
 515         unregister_net_sysctl_table(net->sctp.sysctl_header);
 516         kfree(table);
 517 }
 518
 519 static struct ctl_table_header *sctp_sysctl_header;
 520
 521 /* Sysctl registration.  */
 522 void sctp_sysctl_register(void)
 523 {
 524         sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
 525 }
 526
 527 /* Sysctl deregistration.  */
 528 void sctp_sysctl_unregister(void)
 529 {
 530         unregister_net_sysctl_table(sctp_sysctl_header);
 531 }