qcsrc/server/ipban.qc

   1 #include "ipban.qh"
   2
   3 #include <server/defs.qh>
   4 #include <server/miscfunctions.qh>
   5 #include "autocvars.qh"
   6 #include "command/banning.qh"
   7 #include "defs.qh"
   8 #include "../common/constants.qh"
   9 #include "../common/util.qh"
  10
  11 /*
  12  * Protocol of online ban list:
  13  *
  14  * - Reporting a ban:
  15  *     GET g_ban_sync_uri?action=ban&hostname=...&ip=xxx.xxx.xxx&duration=nnnn&reason=...................
  16  *     (IP 1, 2, 3, or 4 octets, 3 octets for example is a /24 mask)
  17  * - Removing a ban:
  18  *     GET g_ban_sync_uri?action=unban&hostname=...&ip=xxx.xxx.xxx
  19  * - Querying the ban list
  20  *     GET g_ban_sync_uri?action=list&hostname=...&servers=xxx.xxx.xxx.xxx;xxx.xxx.xxx.xxx;...
  21  *
  22  *     shows the bans from the listed servers, and possibly others.
  23  *     Format of a ban is ASCII plain text, four lines per ban, delimited by
  24  *     newline ONLY (no carriage return):
  25  *
  26  *     IP address (also 1, 2, 3, or 4 octets, delimited by dot)
  27  *     time left in seconds
  28  *     reason of the ban
  29  *     server IP that registered the ban
  30  */
  31
  32 #define MAX_IPBAN_URIS (URI_GET_IPBAN_END - URI_GET_IPBAN + 1)
  33
  34 void OnlineBanList_SendBan(string ip, float bantime, string reason)
  35 {
  36         string uri;
  37         float i, n;
  38
  39         uri = strcat(     "action=ban&hostname=", uri_escape(autocvar_hostname));
  40         uri = strcat(uri, "&ip=", uri_escape(ip));
  41         uri = strcat(uri, "&duration=", ftos(bantime));
  42         uri = strcat(uri, "&reason=", uri_escape(reason));
  43
  44         n = tokenize_console(autocvar_g_ban_sync_uri);
  45         if(n >= MAX_IPBAN_URIS)
  46                 n = MAX_IPBAN_URIS;
  47         for(i = 0; i < n; ++i)
  48         {
  49                 if(strstrofs(argv(i), "?", 0) >= 0)
  50                         uri_get(strcat(argv(i), "&", uri), URI_GET_DISCARD); // 0 = "discard" callback target
  51                 else
  52                         uri_get(strcat(argv(i), "?", uri), URI_GET_DISCARD); // 0 = "discard" callback target
  53         }
  54 }
  55
  56 void OnlineBanList_SendUnban(string ip)
  57 {
  58         string uri;
  59         float i, n;
  60
  61         uri = strcat(     "action=unban&hostname=", uri_escape(autocvar_hostname));
  62         uri = strcat(uri, "&ip=", uri_escape(ip));
  63
  64         n = tokenize_console(autocvar_g_ban_sync_uri);
  65         if(n >= MAX_IPBAN_URIS)
  66                 n = MAX_IPBAN_URIS;
  67         for(i = 0; i < n; ++i)
  68         {
  69                 if(strstrofs(argv(i), "?", 0) >= 0)
  70                         uri_get(strcat(argv(i), "&", uri), URI_GET_DISCARD); // 0 = "discard" callback target
  71                 else
  72                         uri_get(strcat(argv(i), "?", uri), URI_GET_DISCARD); // 0 = "discard" callback target
  73         }
  74 }
  75
  76 string OnlineBanList_Servers;
  77 float OnlineBanList_Timeout;
  78 float OnlineBanList_RequestWaiting[MAX_IPBAN_URIS];
  79
  80 void OnlineBanList_URI_Get_Callback(float id, float status, string data)
  81 {
  82         float n, i, j, l;
  83         string ip;
  84         float timeleft;
  85         string reason;
  86         string serverip;
  87         float syncinterval;
  88         string uri;
  89
  90         id -= URI_GET_IPBAN;
  91
  92         if(id >= MAX_IPBAN_URIS)
  93         {
  94                 LOG_INFO("Received ban list for invalid ID");
  95                 return;
  96         }
  97
  98         tokenize_console(autocvar_g_ban_sync_uri);
  99         uri = argv(id);
 100
 101         string prelude = strcat("Received ban list from ", uri, ": ");
 102
 103         if(OnlineBanList_RequestWaiting[id] == 0)
 104         {
 105                 LOG_INFO(prelude, "rejected (unexpected)");
 106                 return;
 107         }
 108
 109         OnlineBanList_RequestWaiting[id] = 0;
 110
 111         if(time > OnlineBanList_Timeout)
 112         {
 113                 LOG_INFO(prelude, "rejected (too late)");
 114                 return;
 115         }
 116
 117         syncinterval = autocvar_g_ban_sync_interval;
 118         if(syncinterval == 0)
 119         {
 120                 LOG_INFO(prelude, "rejected (syncing disabled)");
 121                 return;
 122         }
 123         if(syncinterval > 0)
 124                 syncinterval *= 60;
 125
 126         if(status != 0)
 127         {
 128                 LOG_INFO(prelude, "error: status is ", ftos(status));
 129                 return;
 130         }
 131
 132         if(substring(data, 0, 1) == "<")
 133         {
 134                 LOG_INFO(prelude, "error: received HTML instead of a ban list");
 135                 return;
 136         }
 137
 138         if(strstrofs(data, "\r", 0) != -1)
 139         {
 140                 LOG_INFO(prelude, "error: received carriage returns");
 141                 return;
 142         }
 143
 144         if(data == "")
 145                 n = 0;
 146         else
 147                 n = tokenizebyseparator(data, "\n");
 148
 149         if((n % 4) != 0)
 150         {
 151                 LOG_INFO(prelude, "error: received invalid item count: ", ftos(n));
 152                 return;
 153         }
 154
 155         LOG_INFO(prelude, "OK, ", ftos(n / 4), " items");
 156
 157         for(i = 0; i < n; i += 4)
 158         {
 159                 ip = argv(i);
 160                 timeleft = stof(argv(i + 1));
 161                 reason = argv(i + 2);
 162                 serverip = argv(i + 3);
 163
 164                 LOG_TRACE("received ban list item ", ftos(i / 4), ": ip=", ip);
 165                 LOG_TRACE(" timeleft=", ftos(timeleft), " reason=", reason);
 166                 LOG_TRACE(" serverip=", serverip);
 167
 168                 timeleft -= 1.5 * autocvar_g_ban_sync_timeout;
 169                 if(timeleft < 0)
 170                         continue;
 171
 172                 l = strlen(ip);
 173                 if(l != 44) // length 44 is a cryptographic ID
 174                 {
 175                         for(j = 0; j < l; ++j)
 176                                 if(strstrofs("0123456789.", substring(ip, j, 1), 0) == -1)
 177                                 {
 178                                         LOG_INFO("Invalid character ", substring(ip, j, 1), " in IP address ", ip, ". Skipping this ban.");
 179                                         goto skip;
 180                                 }
 181                 }
 182
 183                 if(autocvar_g_ban_sync_trusted_servers_verify)
 184                         if((strstrofs(strcat(";", OnlineBanList_Servers, ";"), strcat(";", serverip, ";"), 0) == -1))
 185                                 continue;
 186
 187                 if(syncinterval > 0)
 188                         timeleft = min(syncinterval + (OnlineBanList_Timeout - time) + 5, timeleft);
 189                         // the ban will be prolonged on the next sync
 190                         // or expire 5 seconds after the next timeout
 191                 Ban_Insert(ip, timeleft, strcat("ban synced from ", serverip, " at ", uri), 0);
 192                 LOG_INFO("Ban list syncing: accepted ban of ", ip, " by ", serverip, " at ", uri, ": ", reason);
 193
 194 LABEL(skip)
 195         }
 196 }
 197
 198 void OnlineBanList_Think(entity this)
 199 {
 200         int argc;
 201         string uri;
 202         float i, n;
 203
 204         if(autocvar_g_ban_sync_uri == "")
 205                 goto killme;
 206         if(autocvar_g_ban_sync_interval == 0) // < 0 is okay, it means "sync on level start only"
 207                 goto killme;
 208         argc = tokenize_console(autocvar_g_ban_sync_trusted_servers);
 209         if(argc == 0)
 210                 goto killme;
 211
 212         string s = argv(0); for(i = 1; i < argc; ++i) s = strcat(s, ";", argv(i));
 213         strcpy(OnlineBanList_Servers, s);
 214
 215         uri = strcat(     "action=list&hostname=", uri_escape(autocvar_hostname));
 216         uri = strcat(uri, "&servers=", uri_escape(OnlineBanList_Servers));
 217
 218         OnlineBanList_Timeout = time + autocvar_g_ban_sync_timeout;
 219
 220         n = tokenize_console(autocvar_g_ban_sync_uri);
 221         if(n >= MAX_IPBAN_URIS)
 222                 n = MAX_IPBAN_URIS;
 223         for(i = 0; i < n; ++i)
 224         {
 225                 if(OnlineBanList_RequestWaiting[i])
 226                         continue;
 227                 OnlineBanList_RequestWaiting[i] = 1;
 228                 if(strstrofs(argv(i), "?", 0) >= 0)
 229                         uri_get(strcat(argv(i), "&", uri), URI_GET_IPBAN + i); // 1000 = "banlist" callback target
 230                 else
 231                         uri_get(strcat(argv(i), "?", uri), URI_GET_IPBAN + i); // 1000 = "banlist" callback target
 232         }
 233
 234         if(autocvar_g_ban_sync_interval > 0)
 235                 this.nextthink = time + max(60, autocvar_g_ban_sync_interval * 60);
 236         else
 237                 goto killme;
 238         return;
 239
 240 LABEL(killme)
 241         delete(this);
 242 }
 243
 244 const float BAN_MAX = 256;
 245 float ban_loaded;
 246 string ban_ip[BAN_MAX];
 247 float ban_expire[BAN_MAX];
 248 float ban_count;
 249
 250 string ban_ip1;
 251 string ban_ip2;
 252 string ban_ip3;
 253 string ban_ip4;
 254 string ban_idfp;
 255
 256 void Ban_SaveBans()
 257 {
 258         string out;
 259         float i;
 260
 261         if(!ban_loaded)
 262                 return;
 263
 264         // version of list
 265         out = "1";
 266         for(i = 0; i < ban_count; ++i)
 267         {
 268                 if(time > ban_expire[i])
 269                         continue;
 270                 out = strcat(out, " ", ban_ip[i]);
 271                 out = strcat(out, " ", ftos(ban_expire[i] - time));
 272         }
 273         if(strlen(out) <= 1) // no real entries
 274                 cvar_set("g_banned_list", "");
 275         else
 276                 cvar_set("g_banned_list", out);
 277 }
 278
 279 float Ban_Delete(float i)
 280 {
 281         if(i < 0)
 282                 return false;
 283         if(i >= ban_count)
 284                 return false;
 285         if(ban_expire[i] == 0)
 286                 return false;
 287         if(ban_expire[i] > 0)
 288         {
 289                 OnlineBanList_SendUnban(ban_ip[i]);
 290                 strunzone(ban_ip[i]);
 291         }
 292         ban_expire[i] = 0;
 293         ban_ip[i] = "";
 294         Ban_SaveBans();
 295         return true;
 296 }
 297
 298 void Ban_LoadBans()
 299 {
 300         float i, n;
 301         for(i = 0; i < ban_count; ++i)
 302                 Ban_Delete(i);
 303         ban_count = 0;
 304         ban_loaded = true;
 305         n = tokenize_console(autocvar_g_banned_list);
 306         if(stof(argv(0)) == 1)
 307         {
 308                 ban_count = (n - 1) / 2;
 309                 for(i = 0; i < ban_count; ++i)
 310                 {
 311                         ban_ip[i] = strzone(argv(2*i+1));
 312                         ban_expire[i] = time + stof(argv(2*i+2));
 313                 }
 314         }
 315
 316         entity e = new(bansyncer);
 317         setthink(e, OnlineBanList_Think);
 318         e.nextthink = time + 1;
 319 }
 320
 321 void Ban_View()
 322 {
 323         float i, n;
 324         string msg;
 325
 326         LOG_INFO("^2Listing all existing active bans:");
 327
 328         n = 0;
 329         for(i = 0; i < ban_count; ++i)
 330         {
 331                 if(time > ban_expire[i])
 332                         continue;
 333
 334                 ++n; // total number of existing bans
 335
 336                 msg = strcat("#", ftos(i), ": ");
 337                 msg = strcat(msg, ban_ip[i], " is still banned for ");
 338                 msg = strcat(msg, ftos(ban_expire[i] - time), " seconds");
 339
 340                 LOG_INFO("  ", msg);
 341         }
 342
 343         LOG_INFO("^2Done listing all active (", ftos(n), ") bans.");
 344 }
 345
 346 float Ban_GetClientIP(entity client)
 347 {
 348         // we can't use tokenizing here, as this is called during ban list parsing
 349         float i1, i2, i3, i4;
 350         string s;
 351
 352         if(client.crypto_idfp_signed)
 353                 ban_idfp = client.crypto_idfp;
 354         else
 355                 ban_idfp = string_null;
 356
 357         s = client.netaddress;
 358
 359         i1 = strstrofs(s, ".", 0);
 360         if(i1 < 0)
 361                 goto ipv6;
 362         i2 = strstrofs(s, ".", i1 + 1);
 363         if(i2 < 0)
 364                 return false;
 365         i3 = strstrofs(s, ".", i2 + 1);
 366         if(i3 < 0)
 367                 return false;
 368         i4 = strstrofs(s, ".", i3 + 1);
 369         if(i4 >= 0)
 370                 s = substring(s, 0, i4);
 371
 372         ban_ip1 = substring(s, 0, i1); // 8
 373         ban_ip2 = substring(s, 0, i2); // 16
 374         ban_ip3 = substring(s, 0, i3); // 24
 375         ban_ip4 = strcat1(s); // 32
 376         return true;
 377
 378 LABEL(ipv6)
 379         i1 = strstrofs(s, ":", 0);
 380         if(i1 < 0)
 381                 return false;
 382         i1 = strstrofs(s, ":", i1 + 1);
 383         if(i1 < 0)
 384                 return false;
 385         i2 = strstrofs(s, ":", i1 + 1);
 386         if(i2 < 0)
 387                 return false;
 388         i3 = strstrofs(s, ":", i2 + 1);
 389         if(i3 < 0)
 390                 return false;
 391
 392         ban_ip1 = strcat(substring(s, 0, i1), "::/32"); // 32
 393         ban_ip2 = strcat(substring(s, 0, i2), "::/48"); // 48
 394         ban_ip4 = strcat(substring(s, 0, i3), "::/64"); // 64
 395
 396         if(i3 - i2 > 3) // means there is more than 2 digits and a : in the range
 397                 ban_ip3 = strcat(substring(s, 0, i2), ":", substring(s, i2 + 1, i3 - i2 - 3), "00::/56");
 398         else
 399                 ban_ip3 = strcat(substring(s, 0, i2), ":0::/56");
 400
 401         return true;
 402 }
 403
 404 float Ban_IsClientBanned(entity client, float idx)
 405 {
 406         float i, b, e, ipbanned;
 407         if(!ban_loaded)
 408                 Ban_LoadBans();
 409         if(!Ban_GetClientIP(client))
 410                 return false;
 411         if(idx < 0)
 412         {
 413                 b = 0;
 414                 e = ban_count;
 415         }
 416         else
 417         {
 418                 b = idx;
 419                 e = idx + 1;
 420         }
 421         ipbanned = false;
 422         for(i = b; i < e; ++i)
 423         {
 424                 string s;
 425                 if(time > ban_expire[i])
 426                         continue;
 427                 s = ban_ip[i];
 428                 if(ban_ip1 == s) ipbanned = true;
 429                 if(ban_ip2 == s) ipbanned = true;
 430                 if(ban_ip3 == s) ipbanned = true;
 431                 if(ban_ip4 == s) ipbanned = true;
 432                 if(ban_idfp == s) return true;
 433         }
 434         if(ipbanned)
 435         {
 436                 if(!autocvar_g_banned_list_idmode)
 437                         return true;
 438                 if (!ban_idfp)
 439                         return true;
 440         }
 441         return false;
 442 }
 443
 444 bool Ban_MaybeEnforceBan(entity client)
 445 {
 446         if (Ban_IsClientBanned(client, -1))
 447         {
 448                 string s = sprintf("^1NOTE:^7 banned client %s just tried to enter\n", client.netaddress);
 449                 if(autocvar_g_ban_telluser)
 450                         sprint(client, "You are banned from this server.\n");
 451                 dropclient(client);
 452                 bprint(s);
 453                 return true;
 454         }
 455         return false;
 456 }
 457
 458 .bool ban_checked;
 459 bool Ban_MaybeEnforceBanOnce(entity client)
 460 {
 461         if (client.ban_checked) return false;
 462         client.ban_checked = true;
 463         return Ban_MaybeEnforceBan(client);
 464 }
 465
 466 string Ban_Enforce(float j, string reason)
 467 {
 468         string s;
 469
 470         // Enforce our new ban
 471         s = "";
 472         FOREACH_CLIENTSLOT(IS_REAL_CLIENT(it),
 473         {
 474                 if(Ban_IsClientBanned(it, j))
 475                 {
 476                         if(reason != "")
 477                         {
 478                                 if(s == "")
 479                                         reason = strcat(reason, ": affects ");
 480                                 else
 481                                         reason = strcat(reason, ", ");
 482                                 reason = strcat(reason, it.netname);
 483                         }
 484                         s = strcat(s, "^1NOTE:^7 banned client ", it.netaddress, "^7 has to go\n");
 485                         dropclient(it);
 486                 }
 487         });
 488         bprint(s);
 489
 490         return reason;
 491 }
 492
 493 float Ban_Insert(string ip, float bantime, string reason, float dosync)
 494 {
 495         float i;
 496         float j;
 497         float bestscore;
 498
 499         // already banned?
 500         for(i = 0; i < ban_count; ++i)
 501                 if(ban_ip[i] == ip)
 502                 {
 503                         // prolong the ban
 504                         if(time + bantime > ban_expire[i])
 505                         {
 506                                 ban_expire[i] = time + bantime;
 507                                 LOG_TRACE(ip, "'s ban has been prolonged to ", ftos(bantime), " seconds from now");
 508                         }
 509                         else
 510                                 LOG_TRACE(ip, "'s ban is still active until ", ftos(ban_expire[i] - time), " seconds from now");
 511
 512                         // and enforce
 513                         reason = Ban_Enforce(i, reason);
 514
 515                         // and abort
 516                         if(dosync)
 517                                 if(reason != "")
 518                                         if(substring(reason, 0, 1) != "~") // like IRC: unauthenticated banner
 519                                                 OnlineBanList_SendBan(ip, bantime, reason);
 520
 521                         return false;
 522                 }
 523
 524         // do we have a free slot?
 525         for(i = 0; i < ban_count; ++i)
 526                 if(time > ban_expire[i])
 527                         break;
 528         // no free slot? Then look for the one who would get unbanned next
 529         if(i >= BAN_MAX)
 530         {
 531                 i = 0;
 532                 bestscore = ban_expire[i];
 533                 for(j = 1; j < ban_count; ++j)
 534                 {
 535                         if(ban_expire[j] < bestscore)
 536                         {
 537                                 i = j;
 538                                 bestscore = ban_expire[i];
 539                         }
 540                 }
 541         }
 542         // if we replace someone, will we be banned longer than him (so long-term
 543         // bans never get overridden by short-term bans)
 544         if(i < ban_count)
 545         if(ban_expire[i] > time + bantime)
 546         {
 547                 LOG_INFO(ip, " could not get banned due to no free ban slot");
 548                 return false;
 549         }
 550         // okay, insert our new victim as i
 551         Ban_Delete(i);
 552         LOG_TRACE(ip, " has been banned for ", ftos(bantime), " seconds");
 553         ban_expire[i] = time + bantime;
 554         ban_ip[i] = strzone(ip);
 555         ban_count = max(ban_count, i + 1);
 556
 557         Ban_SaveBans();
 558
 559         reason = Ban_Enforce(i, reason);
 560
 561         // and abort
 562         if(dosync)
 563                 if(reason != "")
 564                         if(substring(reason, 0, 1) != "~") // like IRC: unauthenticated banner
 565                                 OnlineBanList_SendBan(ip, bantime, reason);
 566
 567         return true;
 568 }
 569
 570 void Ban_KickBanClient(entity client, float bantime, float masksize, string reason)
 571 {
 572         string ip, id;
 573         if(!Ban_GetClientIP(client))
 574         {
 575                 sprint(client, strcat("Kickbanned: ", reason, "\n"));
 576                 dropclient(client);
 577                 return;
 578         }
 579
 580         // who to ban?
 581         switch(masksize)
 582         {
 583                 case 1:
 584                         ip = strcat1(ban_ip1);
 585                         break;
 586                 case 2:
 587                         ip = strcat1(ban_ip2);
 588                         break;
 589                 case 3:
 590                         ip = strcat1(ban_ip3);
 591                         break;
 592                 case 4:
 593                 default:
 594                         ip = strcat1(ban_ip4);
 595                         break;
 596         }
 597         if(ban_idfp)
 598                 id = strcat1(ban_idfp);
 599         else
 600                 id = string_null;
 601
 602         Ban_Insert(ip, bantime, reason, 1);
 603         if(id)
 604                 Ban_Insert(id, bantime, reason, 1);
 605         /*
 606          * not needed, as we enforce the ban in Ban_Insert anyway
 607         // and kick him
 608         sprint(client, strcat("Kickbanned: ", reason, "\n"));
 609         dropclient(client);
 610          */
 611 }