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