trusts/data.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3 #include <stdio.h>
   4
   5 #include "../lib/sstring.h"
   6 #include "../core/hooks.h"
   7 #include "../core/nsmalloc.h"
   8 #include "../lib/irc_string.h"
   9 #include "trusts.h"
  10
  11 trustgroup *tglist;
  12
  13 void th_dbupdatecounts(trusthost *);
  14 void tg_dbupdatecounts(trustgroup *);
  15
  16 static trusthost *th_getnextchildbyhost(trusthost *, trusthost *);
  17
  18 void trusts_freeall(void) {
  19   trustgroup *tg, *ntg;
  20   trusthost *th, *nth;
  21
  22   for(tg=tglist;tg;tg=ntg) {
  23     ntg = tg->next;
  24     for(th=tg->hosts;th;th=nth) {
  25       nth = th->next;
  26
  27       th_free(th);
  28     }
  29
  30     tg_free(tg);
  31   }
  32
  33   tglist = NULL;
  34 }
  35
  36 trustgroup *tg_getbyid(unsigned int id) {
  37   trustgroup *tg;
  38
  39   for(tg=tglist;tg;tg=tg->next)
  40     if(tg->id == id)
  41       return tg;
  42
  43   return NULL;
  44 }
  45
  46 void th_free(trusthost *th) {
  47   nsfree(POOL_TRUSTS, th);
  48 }
  49
  50 static void th_updatechildren(trusthost *th) {
  51   trusthost *nth = NULL;
  52
  53   th->children = NULL;
  54
  55   for(;;) {
  56     nth = th_getnextchildbyhost(th, nth);
  57     if(!nth)
  58       break;
  59
  60     nth->nextbychild = th->children;
  61     th->children = nth;
  62   }
  63 }
  64
  65 void th_linktree(void) {
  66   trustgroup *tg;
  67   trusthost *th;
  68
  69   /* ugh */
  70   for(tg=tglist;tg;tg=tg->next)
  71     for(th=tg->hosts;th;th=th->next)
  72       th->parent = th_getsmallestsupersetbyhost(th->ip, th->mask);
  73
  74   for(tg=tglist;tg;tg=tg->next)
  75     for(th=tg->hosts;th;th=th->next)
  76       if(th->parent)
  77         th_updatechildren(th->parent);
  78 }
  79
  80 trusthost *th_add(trustgroup *tg, unsigned int id, char *host, unsigned int maxusage, time_t lastseen) {
  81   uint32_t ip, mask;
  82   trusthost *th;
  83
  84   if(!trusts_str2cidr(host, &ip, &mask))
  85     return NULL;
  86
  87   th = nsmalloc(POOL_TRUSTS, sizeof(trusthost));
  88   if(!th)
  89     return NULL;
  90
  91   th->id = id;
  92   th->maxusage = maxusage;
  93   th->lastseen = lastseen;
  94   th->ip = ip;
  95   th->mask = mask;
  96
  97   th->users = NULL;
  98   th->group = tg;
  99   th->count = 0;
 100
 101   th->parent = NULL;
 102   th->children = NULL;
 103
 104   th->marker = 0;
 105
 106   th->next = tg->hosts;
 107   tg->hosts = th;
 108
 109   return th;
 110 }
 111
 112 void tg_free(trustgroup *tg) {
 113   triggerhook(HOOK_TRUSTS_LOSTGROUP, tg);
 114
 115   freesstring(tg->name);
 116   freesstring(tg->createdby);
 117   freesstring(tg->contact);
 118   freesstring(tg->comment);
 119   nsfree(POOL_TRUSTS, tg);
 120 }
 121
 122 trustgroup *tg_add(unsigned int id, char *name, unsigned int trustedfor, int mode, unsigned int maxperident, unsigned int maxusage, time_t expires, time_t lastseen, time_t lastmaxuserreset, char *createdby, char *contact, char *comment) {
 123   trustgroup *tg = nsmalloc(POOL_TRUSTS, sizeof(trustgroup));
 124   if(!tg)
 125     return NULL;
 126
 127   tg->name = getsstring(name, TRUSTNAMELEN);
 128   tg->createdby = getsstring(createdby, NICKLEN);
 129   tg->contact = getsstring(contact, CONTACTLEN);
 130   tg->comment = getsstring(comment, COMMENTLEN);
 131   if(!tg->name || !tg->createdby || !tg->contact || !tg->comment) {
 132     tg_free(tg);
 133     return NULL;
 134   }
 135
 136   tg->id = id;
 137   tg->trustedfor = trustedfor;
 138   tg->mode = mode;
 139   tg->maxperident = maxperident;
 140   tg->maxusage = maxusage;
 141   tg->expires = expires;
 142   tg->lastseen = lastseen;
 143   tg->lastmaxuserreset = lastmaxuserreset;
 144   tg->hosts = NULL;
 145
 146   tg->marker = 0;
 147
 148   tg->count = 0;
 149
 150   memset(tg->exts, 0, sizeof(tg->exts));
 151
 152   tg->next = tglist;
 153   tglist = tg;
 154
 155   triggerhook(HOOK_TRUSTS_NEWGROUP, tg);
 156
 157   return tg;
 158 }
 159
 160 trusthost *th_getbyhost(uint32_t ip) {
 161   trustgroup *tg;
 162   trusthost *th, *result = NULL;
 163   uint32_t mask;
 164
 165   for(tg=tglist;tg;tg=tg->next) {
 166     for(th=tg->hosts;th;th=th->next) {
 167       if((ip & th->mask) == th->ip) {
 168         if(!result || (th->mask > mask)) {
 169           mask = th->mask;
 170           result = th;
 171         }
 172       }
 173     }
 174   }
 175
 176   return result;
 177 }
 178
 179 trusthost *th_getbyhostandmask(uint32_t ip, uint32_t mask) {
 180   trustgroup *tg;
 181   trusthost *th;
 182
 183   for(tg=tglist;tg;tg=tg->next)
 184     for(th=tg->hosts;th;th=th->next)
 185       if((th->ip == ip) && (th->mask == mask))
 186         return th;
 187
 188   return NULL;
 189 }
 190
 191 /* returns the ip with the smallest prefix that is still a superset of the given host */
 192 trusthost *th_getsmallestsupersetbyhost(uint32_t ip, uint32_t mask) {
 193   trustgroup *tg;
 194   trusthost *th, *result = NULL;
 195   uint32_t smask;
 196
 197   for(tg=tglist;tg;tg=tg->next) {
 198     for(th=tg->hosts;th;th=th->next) {
 199       if(th->ip == (ip & th->mask)) {
 200         if((th->mask < mask) && (!result || (th->mask > smask))) {
 201           smask = th->mask;
 202           result = th;
 203         }
 204       }
 205     }
 206   }
 207
 208   return result;
 209 }
 210
 211 /* returns the first ip that is a subset it comes across */
 212 trusthost *th_getsubsetbyhost(uint32_t ip, uint32_t mask) {
 213   trustgroup *tg;
 214   trusthost *th;
 215
 216   for(tg=tglist;tg;tg=tg->next)
 217     for(th=tg->hosts;th;th=th->next)
 218       if((th->ip & mask) == ip)
 219         if(th->mask > mask)
 220           return th;
 221
 222   return NULL;
 223 }
 224
 225 /* NOT reentrant obviously */
 226 static trusthost *th_getnextchildbyhost(trusthost *orig, trusthost *th) {
 227   if(!th) {
 228     trustgroup *tg;
 229
 230     tg = tglist;
 231     for(tg=tglist;tg;tg=tg->next) {
 232       th = tg->hosts;
 233       if(th)
 234         break;
 235     }
 236
 237     /* INVARIANT: tg => th */
 238     if(!tg)
 239       return NULL;
 240
 241     if(th->parent == orig)
 242       return th;
 243   }
 244
 245   for(;;) {
 246     if(th->next) {
 247       th = th->next;
 248     } else {
 249       if(!th->group->next)
 250         return NULL;
 251       th = th->group->next->hosts;
 252     }
 253
 254     if(th->parent == orig)
 255       return th;
 256   }
 257 }
 258
 259 void th_getsuperandsubsets(uint32_t ip, uint32_t mask, trusthost **superset, trusthost **subset) {
 260   *superset = th_getsmallestsupersetbyhost(ip, mask);
 261   *subset = th_getsubsetbyhost(ip, mask);
 262 }
 263
 264 void trusts_flush(void) {
 265   trustgroup *tg;
 266   trusthost *th;
 267   time_t t = time(NULL);
 268
 269   for(tg=tglist;tg;tg=tg->next) {
 270     if(tg->count > 0)
 271       tg->lastseen = t;
 272
 273     tg_dbupdatecounts(tg);
 274
 275     for(th=tg->hosts;th;th=th->next) {
 276       if(th->count > 0)
 277         th->lastseen = t;
 278
 279       th_dbupdatecounts(th);
 280     }
 281   }
 282 }
 283
 284 trustgroup *tg_strtotg(char *name) {
 285   unsigned long id;
 286   trustgroup *tg;
 287
 288   /* legacy format */
 289   if(name[0] == '#') {
 290     id = strtoul(&name[1], NULL, 10);
 291     if(!id)
 292       return NULL;
 293
 294     for(tg=tglist;tg;tg=tg->next)
 295       if(tg->id == id)
 296         return tg;
 297   }
 298
 299   for(tg=tglist;tg;tg=tg->next)
 300     if(!match(name, tg->name->content))
 301       return tg;
 302
 303   id = strtoul(name, NULL, 10);
 304   if(!id)
 305     return NULL;
 306
 307   /* legacy format */
 308   for(tg=tglist;tg;tg=tg->next)
 309     if(tg->id == id)
 310       return tg;
 311
 312   return NULL;
 313 }
 314
 315 void th_adjusthosts(trusthost *th, trusthost *superset, trusthost *subset) {
 316   /*
 317    * First and foremost, CIDR doesn't allow hosts to cross boundaries, i.e. everything with a smaller prefix
 318    * is entirely contained with the prefix that is one smaller.
 319    * e.g. 0.0.0.0/23, 0.0.0.128/23, you can't have a single prefix for 0.0.0.64-0.0.0.192, instead
 320    * you have two, 0.0.0.64/26 and 0.0.0.128/26.
 321    *
 322    * This makes the code MUCH easier as the entire thing is one huge set/tree.
 323    *
 324    * Four cases here:
 325    * 1: host isn't covered by any existing hosts.
 326    * 2: host is covered by a less specific one only, e.g. adding 0.0.0.1/32, while 0.0.0.0/24 already exists.
 327    * 3: host is covered by a more specific one only, e.g. adding 0.0.0.0/24 while 0.0.0.1/32 already exists
 328    *    (note there might be more than one more specific host, e.g. 0.0.0.1/32 and 0.0.0.2/32).
 329    * 4: covered by more and less specific cases, e.g. adding 0.0.0.0/24 to: { 0.0.0.1/32, 0.0.0.2/32, 0.0.0.0/16 }.
 330    *
 331    * CASE 1
 332    * ------
 333    *
 334    * !superset && !subset
 335    *
 336    * Scan through the host hash and add any clients which match our host, this is exactly the same as case 3
 337    * but without needing to check (though checking doesn't hurt), so we'll just use the code for that.
 338    *
 339    * CASE 2
 340    * ------
 341    *
 342    * superset && !subset
 343    *
 344    * We have the less specific host in 'superset', we know it is the only one so pull out clients in it's
 345    * ->users list matching our new host.
 346    * No need to look for extra hosts in the main nick hash as they're all covered already.
 347    *
 348    * CASE 3
 349    * ------
 350    *
 351    * !superset && subset
 352    *
 353    * We have one host in 'subset', but there might be more than one, we don't care though!
 354    * We can scan the entire host hash and pull out any hosts that match us and don't have
 355    * a trust group already, this ignores any with a more specific prefix.
 356    *
 357    * CASE 4
 358    * ------
 359    *
 360    * superset && subset
 361    *
 362    * Here we first fix up the ones less specific then us, so we just perform what we did for case 2,
 363    * then we perform what we did for case 3.
 364    *
 365    * So in summary:
 366    *   CASE 1: DO 3
 367    *   CASE 2: (work)
 368    *   CASE 3: (work)
 369    *   CASE 4: DO 2; DO 3
 370    * Or:
 371    *   if(2 || 4)     : DO 2
 372    *   if(1 || 3 || 4): DO 3
 373    */
 374
 375   /* we let the compiler do the boolean minimisation for clarity reasons */
 376
 377   if((superset && !subset) || (superset && subset)) { /* cases 2 and 4 */
 378     nick *np, *nnp;
 379     for(np=superset->users;np;np=nnp) {
 380       nnp = nextbytrust(np);
 381       if((irc_in_addr_v4_to_int(&np->p_ipaddr) & th->mask) == th->ip) {
 382         trusts_lostnick(np, 1);
 383         trusts_newnick(np, 1);
 384       }
 385     }
 386   }
 387
 388   if((!superset && !subset) || (!superset && subset) || (superset && subset)) { /* cases 1, 3 and 4 */
 389     nick *np;
 390     int i;
 391
 392     for(i=0;i<NICKHASHSIZE;i++)
 393       for(np=nicktable[i];np;np=np->next)
 394         if(!gettrusthost(np) && ((irc_in_addr_v4_to_int(&np->p_ipaddr) & th->mask) == th->ip))
 395           trusts_newnick(np, 1);
 396   }
 397 }
 398
 399 unsigned int nexttgmarker(void) {
 400   static unsigned int tgmarker = 0;
 401   trustgroup *tg;
 402
 403   tgmarker++;
 404   if(!tgmarker) {
 405     /* If we wrapped to zero, zap the marker on all groups */
 406     for(tg=tglist;tg;tg=tg->next)
 407       tg->marker=0;
 408
 409     tgmarker++;
 410   }
 411
 412   return tgmarker;
 413 }
 414
 415 unsigned int nextthmarker(void) {
 416   static unsigned int thmarker = 0;
 417   trustgroup *tg;
 418   trusthost *th;
 419
 420   thmarker++;
 421   if(!thmarker) {
 422     /* If we wrapped to zero, zap the marker on all hosts */
 423     for(tg=tglist;tg;tg=tg->next)
 424       for(th=tg->hosts;th;th=th->next)
 425         th->marker=0;
 426
 427     thmarker++;
 428   }
 429
 430   return thmarker;
 431 }