net/ipv4/sysctl_net_ipv4.c

   1 /*
   2  * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
   3  *
   4  * Begun April 1, 1996, Mike Shaver.
   5  * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
   6  */
   7
   8 #include <linux/mm.h>
   9 #include <linux/module.h>
  10 #include <linux/sysctl.h>
  11 #include <linux/igmp.h>
  12 #include <linux/inetdevice.h>
  13 #include <linux/seqlock.h>
  14 #include <linux/init.h>
  15 #include <net/snmp.h>
  16 #include <net/icmp.h>
  17 #include <net/ip.h>
  18 #include <net/route.h>
  19 #include <net/tcp.h>
  20 #include <net/udp.h>
  21 #include <net/cipso_ipv4.h>
  22 #include <net/inet_frag.h>
  23
  24 static int zero;
  25 static int tcp_retr1_max = 255;
  26 static int ip_local_port_range_min[] = { 1, 1 };
  27 static int ip_local_port_range_max[] = { 65535, 65535 };
  28
  29 extern seqlock_t sysctl_port_range_lock;
  30 extern int sysctl_local_port_range[2];
  31
  32 /* Update system visible IP port range */
  33 static void set_local_port_range(int range[2])
  34 {
  35         write_seqlock(&sysctl_port_range_lock);
  36         sysctl_local_port_range[0] = range[0];
  37         sysctl_local_port_range[1] = range[1];
  38         write_sequnlock(&sysctl_port_range_lock);
  39 }
  40
  41 /* Validate changes from /proc interface. */
  42 static int ipv4_local_port_range(ctl_table *table, int write, struct file *filp,
  43                                  void __user *buffer,
  44                                  size_t *lenp, loff_t *ppos)
  45 {
  46         int ret;
  47         int range[2] = { sysctl_local_port_range[0],
  48                          sysctl_local_port_range[1] };
  49         ctl_table tmp = {
  50                 .data = &range,
  51                 .maxlen = sizeof(range),
  52                 .mode = table->mode,
  53                 .extra1 = &ip_local_port_range_min,
  54                 .extra2 = &ip_local_port_range_max,
  55         };
  56
  57         ret = proc_dointvec_minmax(&tmp, write, filp, buffer, lenp, ppos);
  58
  59         if (write && ret == 0) {
  60                 if (range[1] < range[0])
  61                         ret = -EINVAL;
  62                 else
  63                         set_local_port_range(range);
  64         }
  65
  66         return ret;
  67 }
  68
  69 /* Validate changes from sysctl interface. */
  70 static int ipv4_sysctl_local_port_range(ctl_table *table, int __user *name,
  71                                          int nlen, void __user *oldval,
  72                                          size_t __user *oldlenp,
  73                                         void __user *newval, size_t newlen)
  74 {
  75         int ret;
  76         int range[2] = { sysctl_local_port_range[0],
  77                          sysctl_local_port_range[1] };
  78         ctl_table tmp = {
  79                 .data = &range,
  80                 .maxlen = sizeof(range),
  81                 .mode = table->mode,
  82                 .extra1 = &ip_local_port_range_min,
  83                 .extra2 = &ip_local_port_range_max,
  84         };
  85
  86         ret = sysctl_intvec(&tmp, name, nlen, oldval, oldlenp, newval, newlen);
  87         if (ret == 0 && newval && newlen) {
  88                 if (range[1] < range[0])
  89                         ret = -EINVAL;
  90                 else
  91                         set_local_port_range(range);
  92         }
  93         return ret;
  94 }
  95
  96
  97 static int proc_tcp_congestion_control(ctl_table *ctl, int write, struct file * filp,
  98                                        void __user *buffer, size_t *lenp, loff_t *ppos)
  99 {
 100         char val[TCP_CA_NAME_MAX];
 101         ctl_table tbl = {
 102                 .data = val,
 103                 .maxlen = TCP_CA_NAME_MAX,
 104         };
 105         int ret;
 106
 107         tcp_get_default_congestion_control(val);
 108
 109         ret = proc_dostring(&tbl, write, filp, buffer, lenp, ppos);
 110         if (write && ret == 0)
 111                 ret = tcp_set_default_congestion_control(val);
 112         return ret;
 113 }
 114
 115 static int sysctl_tcp_congestion_control(ctl_table *table, int __user *name,
 116                                          int nlen, void __user *oldval,
 117                                          size_t __user *oldlenp,
 118                                          void __user *newval, size_t newlen)
 119 {
 120         char val[TCP_CA_NAME_MAX];
 121         ctl_table tbl = {
 122                 .data = val,
 123                 .maxlen = TCP_CA_NAME_MAX,
 124         };
 125         int ret;
 126
 127         tcp_get_default_congestion_control(val);
 128         ret = sysctl_string(&tbl, name, nlen, oldval, oldlenp, newval, newlen);
 129         if (ret == 1 && newval && newlen)
 130                 ret = tcp_set_default_congestion_control(val);
 131         return ret;
 132 }
 133
 134 static int proc_tcp_available_congestion_control(ctl_table *ctl,
 135                                                  int write, struct file * filp,
 136                                                  void __user *buffer, size_t *lenp,
 137                                                  loff_t *ppos)
 138 {
 139         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
 140         int ret;
 141
 142         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 143         if (!tbl.data)
 144                 return -ENOMEM;
 145         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
 146         ret = proc_dostring(&tbl, write, filp, buffer, lenp, ppos);
 147         kfree(tbl.data);
 148         return ret;
 149 }
 150
 151 static int proc_allowed_congestion_control(ctl_table *ctl,
 152                                            int write, struct file * filp,
 153                                            void __user *buffer, size_t *lenp,
 154                                            loff_t *ppos)
 155 {
 156         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 157         int ret;
 158
 159         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 160         if (!tbl.data)
 161                 return -ENOMEM;
 162
 163         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 164         ret = proc_dostring(&tbl, write, filp, buffer, lenp, ppos);
 165         if (write && ret == 0)
 166                 ret = tcp_set_allowed_congestion_control(tbl.data);
 167         kfree(tbl.data);
 168         return ret;
 169 }
 170
 171 static int strategy_allowed_congestion_control(ctl_table *table, int __user *name,
 172                                                int nlen, void __user *oldval,
 173                                                size_t __user *oldlenp,
 174                                                void __user *newval,
 175                                                size_t newlen)
 176 {
 177         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 178         int ret;
 179
 180         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 181         if (!tbl.data)
 182                 return -ENOMEM;
 183
 184         tcp_get_available_congestion_control(tbl.data, tbl.maxlen);
 185         ret = sysctl_string(&tbl, name, nlen, oldval, oldlenp, newval, newlen);
 186         if (ret == 1 && newval && newlen)
 187                 ret = tcp_set_allowed_congestion_control(tbl.data);
 188         kfree(tbl.data);
 189
 190         return ret;
 191
 192 }
 193
 194 static struct ctl_table ipv4_table[] = {
 195         {
 196                 .ctl_name       = NET_IPV4_TCP_TIMESTAMPS,
 197                 .procname       = "tcp_timestamps",
 198                 .data           = &sysctl_tcp_timestamps,
 199                 .maxlen         = sizeof(int),
 200                 .mode           = 0644,
 201                 .proc_handler   = &proc_dointvec
 202         },
 203         {
 204                 .ctl_name       = NET_IPV4_TCP_WINDOW_SCALING,
 205                 .procname       = "tcp_window_scaling",
 206                 .data           = &sysctl_tcp_window_scaling,
 207                 .maxlen         = sizeof(int),
 208                 .mode           = 0644,
 209                 .proc_handler   = &proc_dointvec
 210         },
 211         {
 212                 .ctl_name       = NET_IPV4_TCP_SACK,
 213                 .procname       = "tcp_sack",
 214                 .data           = &sysctl_tcp_sack,
 215                 .maxlen         = sizeof(int),
 216                 .mode           = 0644,
 217                 .proc_handler   = &proc_dointvec
 218         },
 219         {
 220                 .ctl_name       = NET_IPV4_TCP_RETRANS_COLLAPSE,
 221                 .procname       = "tcp_retrans_collapse",
 222                 .data           = &sysctl_tcp_retrans_collapse,
 223                 .maxlen         = sizeof(int),
 224                 .mode           = 0644,
 225                 .proc_handler   = &proc_dointvec
 226         },
 227         {
 228                 .ctl_name       = NET_IPV4_DEFAULT_TTL,
 229                 .procname       = "ip_default_ttl",
 230                 .data           = &sysctl_ip_default_ttl,
 231                 .maxlen         = sizeof(int),
 232                 .mode           = 0644,
 233                 .proc_handler   = &ipv4_doint_and_flush,
 234                 .strategy       = &ipv4_doint_and_flush_strategy,
 235                 .extra2         = &init_net,
 236         },
 237         {
 238                 .ctl_name       = NET_IPV4_NO_PMTU_DISC,
 239                 .procname       = "ip_no_pmtu_disc",
 240                 .data           = &ipv4_config.no_pmtu_disc,
 241                 .maxlen         = sizeof(int),
 242                 .mode           = 0644,
 243                 .proc_handler   = &proc_dointvec
 244         },
 245         {
 246                 .ctl_name       = NET_IPV4_NONLOCAL_BIND,
 247                 .procname       = "ip_nonlocal_bind",
 248                 .data           = &sysctl_ip_nonlocal_bind,
 249                 .maxlen         = sizeof(int),
 250                 .mode           = 0644,
 251                 .proc_handler   = &proc_dointvec
 252         },
 253         {
 254                 .ctl_name       = NET_IPV4_TCP_SYN_RETRIES,
 255                 .procname       = "tcp_syn_retries",
 256                 .data           = &sysctl_tcp_syn_retries,
 257                 .maxlen         = sizeof(int),
 258                 .mode           = 0644,
 259                 .proc_handler   = &proc_dointvec
 260         },
 261         {
 262                 .ctl_name       = NET_TCP_SYNACK_RETRIES,
 263                 .procname       = "tcp_synack_retries",
 264                 .data           = &sysctl_tcp_synack_retries,
 265                 .maxlen         = sizeof(int),
 266                 .mode           = 0644,
 267                 .proc_handler   = &proc_dointvec
 268         },
 269         {
 270                 .ctl_name       = NET_TCP_MAX_ORPHANS,
 271                 .procname       = "tcp_max_orphans",
 272                 .data           = &sysctl_tcp_max_orphans,
 273                 .maxlen         = sizeof(int),
 274                 .mode           = 0644,
 275                 .proc_handler   = &proc_dointvec
 276         },
 277         {
 278                 .ctl_name       = NET_TCP_MAX_TW_BUCKETS,
 279                 .procname       = "tcp_max_tw_buckets",
 280                 .data           = &tcp_death_row.sysctl_max_tw_buckets,
 281                 .maxlen         = sizeof(int),
 282                 .mode           = 0644,
 283                 .proc_handler   = &proc_dointvec
 284         },
 285         {
 286                 .ctl_name       = NET_IPV4_DYNADDR,
 287                 .procname       = "ip_dynaddr",
 288                 .data           = &sysctl_ip_dynaddr,
 289                 .maxlen         = sizeof(int),
 290                 .mode           = 0644,
 291                 .proc_handler   = &proc_dointvec
 292         },
 293         {
 294                 .ctl_name       = NET_IPV4_TCP_KEEPALIVE_TIME,
 295                 .procname       = "tcp_keepalive_time",
 296                 .data           = &sysctl_tcp_keepalive_time,
 297                 .maxlen         = sizeof(int),
 298                 .mode           = 0644,
 299                 .proc_handler   = &proc_dointvec_jiffies,
 300                 .strategy       = &sysctl_jiffies
 301         },
 302         {
 303                 .ctl_name       = NET_IPV4_TCP_KEEPALIVE_PROBES,
 304                 .procname       = "tcp_keepalive_probes",
 305                 .data           = &sysctl_tcp_keepalive_probes,
 306                 .maxlen         = sizeof(int),
 307                 .mode           = 0644,
 308                 .proc_handler   = &proc_dointvec
 309         },
 310         {
 311                 .ctl_name       = NET_IPV4_TCP_KEEPALIVE_INTVL,
 312                 .procname       = "tcp_keepalive_intvl",
 313                 .data           = &sysctl_tcp_keepalive_intvl,
 314                 .maxlen         = sizeof(int),
 315                 .mode           = 0644,
 316                 .proc_handler   = &proc_dointvec_jiffies,
 317                 .strategy       = &sysctl_jiffies
 318         },
 319         {
 320                 .ctl_name       = NET_IPV4_TCP_RETRIES1,
 321                 .procname       = "tcp_retries1",
 322                 .data           = &sysctl_tcp_retries1,
 323                 .maxlen         = sizeof(int),
 324                 .mode           = 0644,
 325                 .proc_handler   = &proc_dointvec_minmax,
 326                 .strategy       = &sysctl_intvec,
 327                 .extra2         = &tcp_retr1_max
 328         },
 329         {
 330                 .ctl_name       = NET_IPV4_TCP_RETRIES2,
 331                 .procname       = "tcp_retries2",
 332                 .data           = &sysctl_tcp_retries2,
 333                 .maxlen         = sizeof(int),
 334                 .mode           = 0644,
 335                 .proc_handler   = &proc_dointvec
 336         },
 337         {
 338                 .ctl_name       = NET_IPV4_TCP_FIN_TIMEOUT,
 339                 .procname       = "tcp_fin_timeout",
 340                 .data           = &sysctl_tcp_fin_timeout,
 341                 .maxlen         = sizeof(int),
 342                 .mode           = 0644,
 343                 .proc_handler   = &proc_dointvec_jiffies,
 344                 .strategy       = &sysctl_jiffies
 345         },
 346 #ifdef CONFIG_SYN_COOKIES
 347         {
 348                 .ctl_name       = NET_TCP_SYNCOOKIES,
 349                 .procname       = "tcp_syncookies",
 350                 .data           = &sysctl_tcp_syncookies,
 351                 .maxlen         = sizeof(int),
 352                 .mode           = 0644,
 353                 .proc_handler   = &proc_dointvec
 354         },
 355 #endif
 356         {
 357                 .ctl_name       = NET_TCP_TW_RECYCLE,
 358                 .procname       = "tcp_tw_recycle",
 359                 .data           = &tcp_death_row.sysctl_tw_recycle,
 360                 .maxlen         = sizeof(int),
 361                 .mode           = 0644,
 362                 .proc_handler   = &proc_dointvec
 363         },
 364         {
 365                 .ctl_name       = NET_TCP_ABORT_ON_OVERFLOW,
 366                 .procname       = "tcp_abort_on_overflow",
 367                 .data           = &sysctl_tcp_abort_on_overflow,
 368                 .maxlen         = sizeof(int),
 369                 .mode           = 0644,
 370                 .proc_handler   = &proc_dointvec
 371         },
 372         {
 373                 .ctl_name       = NET_TCP_STDURG,
 374                 .procname       = "tcp_stdurg",
 375                 .data           = &sysctl_tcp_stdurg,
 376                 .maxlen         = sizeof(int),
 377                 .mode           = 0644,
 378                 .proc_handler   = &proc_dointvec
 379         },
 380         {
 381                 .ctl_name       = NET_TCP_RFC1337,
 382                 .procname       = "tcp_rfc1337",
 383                 .data           = &sysctl_tcp_rfc1337,
 384                 .maxlen         = sizeof(int),
 385                 .mode           = 0644,
 386                 .proc_handler   = &proc_dointvec
 387         },
 388         {
 389                 .ctl_name       = NET_TCP_MAX_SYN_BACKLOG,
 390                 .procname       = "tcp_max_syn_backlog",
 391                 .data           = &sysctl_max_syn_backlog,
 392                 .maxlen         = sizeof(int),
 393                 .mode           = 0644,
 394                 .proc_handler   = &proc_dointvec
 395         },
 396         {
 397                 .ctl_name       = NET_IPV4_LOCAL_PORT_RANGE,
 398                 .procname       = "ip_local_port_range",
 399                 .data           = &sysctl_local_port_range,
 400                 .maxlen         = sizeof(sysctl_local_port_range),
 401                 .mode           = 0644,
 402                 .proc_handler   = &ipv4_local_port_range,
 403                 .strategy       = &ipv4_sysctl_local_port_range,
 404         },
 405 #ifdef CONFIG_IP_MULTICAST
 406         {
 407                 .ctl_name       = NET_IPV4_IGMP_MAX_MEMBERSHIPS,
 408                 .procname       = "igmp_max_memberships",
 409                 .data           = &sysctl_igmp_max_memberships,
 410                 .maxlen         = sizeof(int),
 411                 .mode           = 0644,
 412                 .proc_handler   = &proc_dointvec
 413         },
 414
 415 #endif
 416         {
 417                 .ctl_name       = NET_IPV4_IGMP_MAX_MSF,
 418                 .procname       = "igmp_max_msf",
 419                 .data           = &sysctl_igmp_max_msf,
 420                 .maxlen         = sizeof(int),
 421                 .mode           = 0644,
 422                 .proc_handler   = &proc_dointvec
 423         },
 424         {
 425                 .ctl_name       = NET_IPV4_INET_PEER_THRESHOLD,
 426                 .procname       = "inet_peer_threshold",
 427                 .data           = &inet_peer_threshold,
 428                 .maxlen         = sizeof(int),
 429                 .mode           = 0644,
 430                 .proc_handler   = &proc_dointvec
 431         },
 432         {
 433                 .ctl_name       = NET_IPV4_INET_PEER_MINTTL,
 434                 .procname       = "inet_peer_minttl",
 435                 .data           = &inet_peer_minttl,
 436                 .maxlen         = sizeof(int),
 437                 .mode           = 0644,
 438                 .proc_handler   = &proc_dointvec_jiffies,
 439                 .strategy       = &sysctl_jiffies
 440         },
 441         {
 442                 .ctl_name       = NET_IPV4_INET_PEER_MAXTTL,
 443                 .procname       = "inet_peer_maxttl",
 444                 .data           = &inet_peer_maxttl,
 445                 .maxlen         = sizeof(int),
 446                 .mode           = 0644,
 447                 .proc_handler   = &proc_dointvec_jiffies,
 448                 .strategy       = &sysctl_jiffies
 449         },
 450         {
 451                 .ctl_name       = NET_IPV4_INET_PEER_GC_MINTIME,
 452                 .procname       = "inet_peer_gc_mintime",
 453                 .data           = &inet_peer_gc_mintime,
 454                 .maxlen         = sizeof(int),
 455                 .mode           = 0644,
 456                 .proc_handler   = &proc_dointvec_jiffies,
 457                 .strategy       = &sysctl_jiffies
 458         },
 459         {
 460                 .ctl_name       = NET_IPV4_INET_PEER_GC_MAXTIME,
 461                 .procname       = "inet_peer_gc_maxtime",
 462                 .data           = &inet_peer_gc_maxtime,
 463                 .maxlen         = sizeof(int),
 464                 .mode           = 0644,
 465                 .proc_handler   = &proc_dointvec_jiffies,
 466                 .strategy       = &sysctl_jiffies
 467         },
 468         {
 469                 .ctl_name       = NET_TCP_ORPHAN_RETRIES,
 470                 .procname       = "tcp_orphan_retries",
 471                 .data           = &sysctl_tcp_orphan_retries,
 472                 .maxlen         = sizeof(int),
 473                 .mode           = 0644,
 474                 .proc_handler   = &proc_dointvec
 475         },
 476         {
 477                 .ctl_name       = NET_TCP_FACK,
 478                 .procname       = "tcp_fack",
 479                 .data           = &sysctl_tcp_fack,
 480                 .maxlen         = sizeof(int),
 481                 .mode           = 0644,
 482                 .proc_handler   = &proc_dointvec
 483         },
 484         {
 485                 .ctl_name       = NET_TCP_REORDERING,
 486                 .procname       = "tcp_reordering",
 487                 .data           = &sysctl_tcp_reordering,
 488                 .maxlen         = sizeof(int),
 489                 .mode           = 0644,
 490                 .proc_handler   = &proc_dointvec
 491         },
 492         {
 493                 .ctl_name       = NET_TCP_ECN,
 494                 .procname       = "tcp_ecn",
 495                 .data           = &sysctl_tcp_ecn,
 496                 .maxlen         = sizeof(int),
 497                 .mode           = 0644,
 498                 .proc_handler   = &proc_dointvec
 499         },
 500         {
 501                 .ctl_name       = NET_TCP_DSACK,
 502                 .procname       = "tcp_dsack",
 503                 .data           = &sysctl_tcp_dsack,
 504                 .maxlen         = sizeof(int),
 505                 .mode           = 0644,
 506                 .proc_handler   = &proc_dointvec
 507         },
 508         {
 509                 .ctl_name       = NET_TCP_MEM,
 510                 .procname       = "tcp_mem",
 511                 .data           = &sysctl_tcp_mem,
 512                 .maxlen         = sizeof(sysctl_tcp_mem),
 513                 .mode           = 0644,
 514                 .proc_handler   = &proc_dointvec
 515         },
 516         {
 517                 .ctl_name       = NET_TCP_WMEM,
 518                 .procname       = "tcp_wmem",
 519                 .data           = &sysctl_tcp_wmem,
 520                 .maxlen         = sizeof(sysctl_tcp_wmem),
 521                 .mode           = 0644,
 522                 .proc_handler   = &proc_dointvec
 523         },
 524         {
 525                 .ctl_name       = NET_TCP_RMEM,
 526                 .procname       = "tcp_rmem",
 527                 .data           = &sysctl_tcp_rmem,
 528                 .maxlen         = sizeof(sysctl_tcp_rmem),
 529                 .mode           = 0644,
 530                 .proc_handler   = &proc_dointvec
 531         },
 532         {
 533                 .ctl_name       = NET_TCP_APP_WIN,
 534                 .procname       = "tcp_app_win",
 535                 .data           = &sysctl_tcp_app_win,
 536                 .maxlen         = sizeof(int),
 537                 .mode           = 0644,
 538                 .proc_handler   = &proc_dointvec
 539         },
 540         {
 541                 .ctl_name       = NET_TCP_ADV_WIN_SCALE,
 542                 .procname       = "tcp_adv_win_scale",
 543                 .data           = &sysctl_tcp_adv_win_scale,
 544                 .maxlen         = sizeof(int),
 545                 .mode           = 0644,
 546                 .proc_handler   = &proc_dointvec
 547         },
 548         {
 549                 .ctl_name       = NET_TCP_TW_REUSE,
 550                 .procname       = "tcp_tw_reuse",
 551                 .data           = &sysctl_tcp_tw_reuse,
 552                 .maxlen         = sizeof(int),
 553                 .mode           = 0644,
 554                 .proc_handler   = &proc_dointvec
 555         },
 556         {
 557                 .ctl_name       = NET_TCP_FRTO,
 558                 .procname       = "tcp_frto",
 559                 .data           = &sysctl_tcp_frto,
 560                 .maxlen         = sizeof(int),
 561                 .mode           = 0644,
 562                 .proc_handler   = &proc_dointvec
 563         },
 564         {
 565                 .ctl_name       = NET_TCP_FRTO_RESPONSE,
 566                 .procname       = "tcp_frto_response",
 567                 .data           = &sysctl_tcp_frto_response,
 568                 .maxlen         = sizeof(int),
 569                 .mode           = 0644,
 570                 .proc_handler   = &proc_dointvec
 571         },
 572         {
 573                 .ctl_name       = NET_TCP_LOW_LATENCY,
 574                 .procname       = "tcp_low_latency",
 575                 .data           = &sysctl_tcp_low_latency,
 576                 .maxlen         = sizeof(int),
 577                 .mode           = 0644,
 578                 .proc_handler   = &proc_dointvec
 579         },
 580         {
 581                 .ctl_name       = NET_TCP_NO_METRICS_SAVE,
 582                 .procname       = "tcp_no_metrics_save",
 583                 .data           = &sysctl_tcp_nometrics_save,
 584                 .maxlen         = sizeof(int),
 585                 .mode           = 0644,
 586                 .proc_handler   = &proc_dointvec,
 587         },
 588         {
 589                 .ctl_name       = NET_TCP_MODERATE_RCVBUF,
 590                 .procname       = "tcp_moderate_rcvbuf",
 591                 .data           = &sysctl_tcp_moderate_rcvbuf,
 592                 .maxlen         = sizeof(int),
 593                 .mode           = 0644,
 594                 .proc_handler   = &proc_dointvec,
 595         },
 596         {
 597                 .ctl_name       = NET_TCP_TSO_WIN_DIVISOR,
 598                 .procname       = "tcp_tso_win_divisor",
 599                 .data           = &sysctl_tcp_tso_win_divisor,
 600                 .maxlen         = sizeof(int),
 601                 .mode           = 0644,
 602                 .proc_handler   = &proc_dointvec,
 603         },
 604         {
 605                 .ctl_name       = NET_TCP_CONG_CONTROL,
 606                 .procname       = "tcp_congestion_control",
 607                 .mode           = 0644,
 608                 .maxlen         = TCP_CA_NAME_MAX,
 609                 .proc_handler   = &proc_tcp_congestion_control,
 610                 .strategy       = &sysctl_tcp_congestion_control,
 611         },
 612         {
 613                 .ctl_name       = NET_TCP_ABC,
 614                 .procname       = "tcp_abc",
 615                 .data           = &sysctl_tcp_abc,
 616                 .maxlen         = sizeof(int),
 617                 .mode           = 0644,
 618                 .proc_handler   = &proc_dointvec,
 619         },
 620         {
 621                 .ctl_name       = NET_TCP_MTU_PROBING,
 622                 .procname       = "tcp_mtu_probing",
 623                 .data           = &sysctl_tcp_mtu_probing,
 624                 .maxlen         = sizeof(int),
 625                 .mode           = 0644,
 626                 .proc_handler   = &proc_dointvec,
 627         },
 628         {
 629                 .ctl_name       = NET_TCP_BASE_MSS,
 630                 .procname       = "tcp_base_mss",
 631                 .data           = &sysctl_tcp_base_mss,
 632                 .maxlen         = sizeof(int),
 633                 .mode           = 0644,
 634                 .proc_handler   = &proc_dointvec,
 635         },
 636         {
 637                 .ctl_name       = NET_IPV4_TCP_WORKAROUND_SIGNED_WINDOWS,
 638                 .procname       = "tcp_workaround_signed_windows",
 639                 .data           = &sysctl_tcp_workaround_signed_windows,
 640                 .maxlen         = sizeof(int),
 641                 .mode           = 0644,
 642                 .proc_handler   = &proc_dointvec
 643         },
 644 #ifdef CONFIG_NET_DMA
 645         {
 646                 .ctl_name       = NET_TCP_DMA_COPYBREAK,
 647                 .procname       = "tcp_dma_copybreak",
 648                 .data           = &sysctl_tcp_dma_copybreak,
 649                 .maxlen         = sizeof(int),
 650                 .mode           = 0644,
 651                 .proc_handler   = &proc_dointvec
 652         },
 653 #endif
 654         {
 655                 .ctl_name       = NET_TCP_SLOW_START_AFTER_IDLE,
 656                 .procname       = "tcp_slow_start_after_idle",
 657                 .data           = &sysctl_tcp_slow_start_after_idle,
 658                 .maxlen         = sizeof(int),
 659                 .mode           = 0644,
 660                 .proc_handler   = &proc_dointvec
 661         },
 662 #ifdef CONFIG_NETLABEL
 663         {
 664                 .ctl_name       = NET_CIPSOV4_CACHE_ENABLE,
 665                 .procname       = "cipso_cache_enable",
 666                 .data           = &cipso_v4_cache_enabled,
 667                 .maxlen         = sizeof(int),
 668                 .mode           = 0644,
 669                 .proc_handler   = &proc_dointvec,
 670         },
 671         {
 672                 .ctl_name       = NET_CIPSOV4_CACHE_BUCKET_SIZE,
 673                 .procname       = "cipso_cache_bucket_size",
 674                 .data           = &cipso_v4_cache_bucketsize,
 675                 .maxlen         = sizeof(int),
 676                 .mode           = 0644,
 677                 .proc_handler   = &proc_dointvec,
 678         },
 679         {
 680                 .ctl_name       = NET_CIPSOV4_RBM_OPTFMT,
 681                 .procname       = "cipso_rbm_optfmt",
 682                 .data           = &cipso_v4_rbm_optfmt,
 683                 .maxlen         = sizeof(int),
 684                 .mode           = 0644,
 685                 .proc_handler   = &proc_dointvec,
 686         },
 687         {
 688                 .ctl_name       = NET_CIPSOV4_RBM_STRICTVALID,
 689                 .procname       = "cipso_rbm_strictvalid",
 690                 .data           = &cipso_v4_rbm_strictvalid,
 691                 .maxlen         = sizeof(int),
 692                 .mode           = 0644,
 693                 .proc_handler   = &proc_dointvec,
 694         },
 695 #endif /* CONFIG_NETLABEL */
 696         {
 697                 .procname       = "tcp_available_congestion_control",
 698                 .maxlen         = TCP_CA_BUF_MAX,
 699                 .mode           = 0444,
 700                 .proc_handler   = &proc_tcp_available_congestion_control,
 701         },
 702         {
 703                 .ctl_name       = NET_TCP_ALLOWED_CONG_CONTROL,
 704                 .procname       = "tcp_allowed_congestion_control",
 705                 .maxlen         = TCP_CA_BUF_MAX,
 706                 .mode           = 0644,
 707                 .proc_handler   = &proc_allowed_congestion_control,
 708                 .strategy       = &strategy_allowed_congestion_control,
 709         },
 710         {
 711                 .ctl_name       = NET_TCP_MAX_SSTHRESH,
 712                 .procname       = "tcp_max_ssthresh",
 713                 .data           = &sysctl_tcp_max_ssthresh,
 714                 .maxlen         = sizeof(int),
 715                 .mode           = 0644,
 716                 .proc_handler   = &proc_dointvec,
 717         },
 718         {
 719                 .ctl_name       = CTL_UNNUMBERED,
 720                 .procname       = "udp_mem",
 721                 .data           = &sysctl_udp_mem,
 722                 .maxlen         = sizeof(sysctl_udp_mem),
 723                 .mode           = 0644,
 724                 .proc_handler   = &proc_dointvec_minmax,
 725                 .strategy       = &sysctl_intvec,
 726                 .extra1         = &zero
 727         },
 728         {
 729                 .ctl_name       = CTL_UNNUMBERED,
 730                 .procname       = "udp_rmem_min",
 731                 .data           = &sysctl_udp_rmem_min,
 732                 .maxlen         = sizeof(sysctl_udp_rmem_min),
 733                 .mode           = 0644,
 734                 .proc_handler   = &proc_dointvec_minmax,
 735                 .strategy       = &sysctl_intvec,
 736                 .extra1         = &zero
 737         },
 738         {
 739                 .ctl_name       = CTL_UNNUMBERED,
 740                 .procname       = "udp_wmem_min",
 741                 .data           = &sysctl_udp_wmem_min,
 742                 .maxlen         = sizeof(sysctl_udp_wmem_min),
 743                 .mode           = 0644,
 744                 .proc_handler   = &proc_dointvec_minmax,
 745                 .strategy       = &sysctl_intvec,
 746                 .extra1         = &zero
 747         },
 748         { .ctl_name = 0 }
 749 };
 750
 751 static struct ctl_table ipv4_net_table[] = {
 752         {
 753                 .ctl_name       = NET_IPV4_ICMP_ECHO_IGNORE_ALL,
 754                 .procname       = "icmp_echo_ignore_all",
 755                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 756                 .maxlen         = sizeof(int),
 757                 .mode           = 0644,
 758                 .proc_handler   = &proc_dointvec
 759         },
 760         {
 761                 .ctl_name       = NET_IPV4_ICMP_ECHO_IGNORE_BROADCASTS,
 762                 .procname       = "icmp_echo_ignore_broadcasts",
 763                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 764                 .maxlen         = sizeof(int),
 765                 .mode           = 0644,
 766                 .proc_handler   = &proc_dointvec
 767         },
 768         {
 769                 .ctl_name       = NET_IPV4_ICMP_IGNORE_BOGUS_ERROR_RESPONSES,
 770                 .procname       = "icmp_ignore_bogus_error_responses",
 771                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 772                 .maxlen         = sizeof(int),
 773                 .mode           = 0644,
 774                 .proc_handler   = &proc_dointvec
 775         },
 776         {
 777                 .ctl_name       = NET_IPV4_ICMP_ERRORS_USE_INBOUND_IFADDR,
 778                 .procname       = "icmp_errors_use_inbound_ifaddr",
 779                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 780                 .maxlen         = sizeof(int),
 781                 .mode           = 0644,
 782                 .proc_handler   = &proc_dointvec
 783         },
 784         {
 785                 .ctl_name       = NET_IPV4_ICMP_RATELIMIT,
 786                 .procname       = "icmp_ratelimit",
 787                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 788                 .maxlen         = sizeof(int),
 789                 .mode           = 0644,
 790                 .proc_handler   = &proc_dointvec_ms_jiffies,
 791                 .strategy       = &sysctl_ms_jiffies
 792         },
 793         {
 794                 .ctl_name       = NET_IPV4_ICMP_RATEMASK,
 795                 .procname       = "icmp_ratemask",
 796                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 797                 .maxlen         = sizeof(int),
 798                 .mode           = 0644,
 799                 .proc_handler   = &proc_dointvec
 800         },
 801         { }
 802 };
 803
 804 struct ctl_path net_ipv4_ctl_path[] = {
 805         { .procname = "net", .ctl_name = CTL_NET, },
 806         { .procname = "ipv4", .ctl_name = NET_IPV4, },
 807         { },
 808 };
 809 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
 810
 811 static __net_init int ipv4_sysctl_init_net(struct net *net)
 812 {
 813         struct ctl_table *table;
 814
 815         table = ipv4_net_table;
 816         if (net != &init_net) {
 817                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
 818                 if (table == NULL)
 819                         goto err_alloc;
 820
 821                 table[0].data =
 822                         &net->ipv4.sysctl_icmp_echo_ignore_all;
 823                 table[1].data =
 824                         &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
 825                 table[2].data =
 826                         &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
 827                 table[3].data =
 828                         &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
 829                 table[4].data =
 830                         &net->ipv4.sysctl_icmp_ratelimit;
 831                 table[5].data =
 832                         &net->ipv4.sysctl_icmp_ratemask;
 833         }
 834
 835         net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
 836                         net_ipv4_ctl_path, table);
 837         if (net->ipv4.ipv4_hdr == NULL)
 838                 goto err_reg;
 839
 840         return 0;
 841
 842 err_reg:
 843         if (net != &init_net)
 844                 kfree(table);
 845 err_alloc:
 846         return -ENOMEM;
 847 }
 848
 849 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
 850 {
 851         struct ctl_table *table;
 852
 853         table = net->ipv4.ipv4_hdr->ctl_table_arg;
 854         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
 855         kfree(table);
 856 }
 857
 858 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
 859         .init = ipv4_sysctl_init_net,
 860         .exit = ipv4_sysctl_exit_net,
 861 };
 862
 863 static __init int sysctl_ipv4_init(void)
 864 {
 865         struct ctl_table_header *hdr;
 866
 867         hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
 868         if (hdr == NULL)
 869                 return -ENOMEM;
 870
 871         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
 872                 unregister_sysctl_table(hdr);
 873                 return -ENOMEM;
 874         }
 875
 876         return 0;
 877 }
 878
 879 __initcall(sysctl_ipv4_init);