chanserv/authtracker/authtracker_db.c

   1 /* Keeps track of current "dangling" auths.
   2  *
   3  * Every entry here corresponds to a user who has an open session in the
   4  * session table, but we cannot be sure that the user has actually gone.
   5  * This means either (a) their server has split off or (b) we restarted and
   6  * found a dangling entry in the session table.
   7  *
   8  * Entries leave when either (a) the user comes back (the entry is dropped),
   9  * or (b) the server the user was on relinks without them, in which case we
  10  * close off their session.
  11  */
  12
  13 #include "authtracker.h"
  14 #include "../../core/nsmalloc.h"
  15 #include "../../server/server.h"
  16 #include "../../irc/irc_config.h"
  17
  18 #include <time.h>
  19
  20 #define DANGLING_HASHSIZE       500
  21 #define dangling_hash(x)        ((x)%DANGLING_HASHSIZE)
  22
  23 #define ALLOCUNIT       100
  24
  25 struct dangling_entry {
  26   unsigned int  numeric;
  27   unsigned long userid;
  28   time_t        authts;
  29   time_t        losttime;
  30   int           reason; /* AT_NETSPLIT or AT_RESTART */
  31   struct dangling_entry *next;
  32 };
  33
  34 struct dangling_server {
  35   struct dangling_entry *de[DANGLING_HASHSIZE];
  36 };
  37
  38 struct dangling_server *ds[MAXSERVERS];
  39 struct dangling_entry *free_des;
  40
  41 static struct dangling_entry *get_de() {
  42   struct dangling_entry *dep;
  43   int i;
  44
  45   if (free_des == NULL) {
  46     free_des = (struct dangling_entry *)nsmalloc(POOL_AUTHTRACKER, ALLOCUNIT * sizeof(struct dangling_entry));
  47     for (i=0;i<(ALLOCUNIT-1);i++) {
  48       free_des[i].next= &(free_des[i+1]);
  49     }
  50     free_des[ALLOCUNIT-1].next=NULL;
  51   }
  52
  53   dep=free_des;
  54   free_des=dep->next;
  55
  56   return dep;
  57 }
  58
  59 static void free_de(struct dangling_entry *dep) {
  60   dep->next=free_des;
  61   free_des=dep;
  62 }
  63
  64 void at_lostnick(unsigned int numeric, unsigned long userid, time_t accountts, time_t losttime, int reason) {
  65   unsigned int server=homeserver(numeric);
  66   unsigned int i;
  67   struct dangling_entry *dep;
  68   unsigned int thehash=dangling_hash(numeric);
  69
  70   /* If their server doesn't have an entry, make one. */
  71   if (!ds[server]) {
  72     ds[server]=nsmalloc(POOL_AUTHTRACKER, sizeof(struct dangling_server));
  73     for (i=0;i<DANGLING_HASHSIZE;i++)
  74       ds[server]->de[i]=NULL;
  75   }
  76
  77   /* Now make an entry */
  78   dep=get_de();
  79   dep->numeric=numeric;
  80   dep->userid=userid;
  81   dep->authts=accountts;
  82   dep->losttime=losttime;
  83   dep->reason=reason;
  84   dep->next=ds[server]->de[thehash];
  85   ds[server]->de[thehash]=dep;
  86 }
  87
  88 /* Removes a returning user from the "dangling" tables.  Return 1 if we found it, 0 otherwise. */
  89 int at_foundnick(unsigned int numeric, unsigned long userid, time_t accountts) {
  90   unsigned int server=homeserver(numeric);
  91   struct dangling_entry *dep, **deh;
  92   unsigned int thehash=dangling_hash(numeric);
  93
  94   /* If we've not got an entry for their server we certainly won't for them. */
  95   if (!ds[server])
  96     return 0;
  97
  98   for (deh=&(ds[server]->de[thehash]); *deh; deh=&((*deh)->next)) {
  99     dep=*deh;
 100     if ((dep->numeric == numeric) && (dep->userid==userid) && (dep->authts==accountts)) {
 101       /* Got it */
 102       *deh=dep->next;
 103       free_de(dep);
 104       return 1;
 105     }
 106   }
 107
 108   /* Dropped through - didn't find it */
 109   return 0;
 110 }
 111
 112 /* When a server is back (fully linked), any remaining dangling users on that server are definately gone. */
 113 void at_serverback(unsigned int server) {
 114   int i;
 115   struct dangling_entry *dep, *ndep;
 116
 117   if (!ds[server])
 118     return;
 119
 120   for (i=0;i<DANGLING_HASHSIZE;i++) {
 121     for (dep=ds[server]->de[i];dep;dep=ndep) {
 122       ndep=dep->next;
 123
 124       at_logquit(dep->userid, dep->authts, time(NULL), (dep->reason==AT_NETSPLIT)? "(netsplit)" : "(restart)");
 125       free_de(dep);
 126     }
 127   }
 128
 129   nsfree(POOL_AUTHTRACKER, ds[server]);
 130   ds[server]=NULL;
 131 }
 132
 133 void at_flushghosts() {
 134   int i;
 135
 136   for (i=0;i<MAXSERVERS;i++) {
 137     if (serverlist[i].linkstate == LS_LINKED)
 138       at_serverback(i);
 139   }
 140 }