channel/channelbans.c

   1 /* channelbans.c */
   2
   3 #include <assert.h>
   4 #include <string.h>
   5 #include <stdio.h>
   6
   7 #include "channel.h"
   8 #include "../nick/nick.h"
   9 #include "../lib/irc_string.h"
  10 #include "../irc/irc_config.h"
  11 #include "../irc/irc.h"
  12 #include "../lib/irc_ipv6.h"
  13
  14 /*
  15  * nickmatchban:
  16  *  Returns true iff the supplied nick* matches the supplied ban*
  17  *
  18  * "visibleonly" flag indicates that we shouldn't check against the real
  19  * host if it's masked.
  20  */
  21
  22 int nickmatchban(nick *np, chanban *bp, int visibleonly) {
  23   char fakehost[HOSTLEN+1];
  24   char *ident;
  25
  26   /* nick/ident section: return 0 (no match) if they don't match */
  27   if (bp->flags & CHANBAN_INVALID)
  28     return 0;
  29
  30   /* Pick up the visible username.  If a sethost username is set, the real
  31    * username is not checked. */
  32   ident=np->ident;
  33   if (IsSetHost(np) && np->shident)
  34     ident=np->shident->content;
  35
  36   if (bp->flags & CHANBAN_USEREXACT &&
  37       ircd_strcmp(ident,bp->user->content))
  38     return 0;
  39
  40   if (bp->flags & CHANBAN_NICKEXACT && ircd_strcmp(np->nick,bp->nick->content))
  41     return 0;
  42
  43   if (bp->flags & CHANBAN_USERMASK &&
  44       !match2strings(bp->user->content,ident))
  45     return 0;
  46
  47   if (bp->flags & CHANBAN_NICKMASK && !match2strings(bp->nick->content,np->nick))
  48      return 0;
  49
  50   /* host section.  Return 1 (match) if they do match
  51    * Note that if user or ident was specified, they've already been checked
  52    */
  53
  54   if (bp->flags & CHANBAN_HOSTANY)
  55     return 1;
  56
  57   if ((bp->flags & CHANBAN_IP) && !(visibleonly && (IsSetHost(np) || (IsAccount(np) && IsHideHost(np))))) {
  58     if (ipmask_check(&(np->ipnode->prefix->sin), &(bp->ipaddr), bp->prefixlen))
  59       return 1;
  60   }
  61
  62   /* Hostname bans need to be checked against +x host, +h host (if set)
  63    * and actual host.  Note that the +x host is only generated (and checked) if it's
  64    * possible for the ban to match a hidden host.. */
  65
  66   if ((bp->flags & CHANBAN_HIDDENHOST) && IsAccount(np)) {
  67     sprintf(fakehost,"%s.%s",np->authname, HIS_HIDDENHOST);
  68
  69     if ((bp->flags & CHANBAN_HOSTEXACT) &&
  70          !ircd_strcmp(fakehost, bp->host->content))
  71       return 1;
  72
  73     if ((bp->flags & CHANBAN_HOSTMASK) &&
  74          match2strings(bp->host->content, fakehost))
  75       return 1;
  76   }
  77
  78   if (IsSetHost(np)) {
  79     if ((bp->flags & CHANBAN_HOSTEXACT) &&
  80           !ircd_strcmp(np->sethost->content, bp->host->content))
  81       return 1;
  82
  83     if ((bp->flags & CHANBAN_HOSTMASK) &&
  84           match2strings(bp->host->content, np->sethost->content))
  85       return 1;
  86   }
  87
  88   /* If we are only checking visible host and the host is somehow masked, don't check
  89    * against the real one. */
  90   if (visibleonly && (IsSetHost(np) || (IsAccount(np) && IsHideHost(np))))
  91     return 0;
  92
  93   if (bp->flags & CHANBAN_HOSTEXACT && !ircd_strcmp(np->host->name->content,bp->host->content))
  94     return 1;
  95
  96   if (bp->flags & CHANBAN_HOSTMASK && match2strings(bp->host->content,np->host->name->content))
  97     return 1;
  98
  99   return 0;
 100 }
 101
 102 /*
 103  * nickbanned:
 104  *  Returns true iff the supplied nick* is banned on the supplied chan*
 105  *
 106  * Pass the visibleonly flag on to nickbanned().
 107  */
 108 int nickbanned(nick *np, channel *cp, int visibleonly) {
 109   chanban *cbp;
 110
 111   for (cbp=cp->bans;cbp;cbp=cbp->next) {
 112     if (nickmatchban(np,cbp,visibleonly))
 113       return 1;
 114   }
 115
 116   return 0;
 117 }
 118
 119 /*
 120  * setban:
 121  *  Set the specified ban; if it completely encloses any existing bans
 122  *  then remove them.
 123  *
 124  * Returns 1 if the ban was set, or 0 if the ban was not set because an
 125  * existing ban overlapped it.
 126  */
 127
 128 int setban(channel *cp, const char *ban) {
 129   chanban **cbh,*cbp,*cbp2;
 130
 131   cbp=makeban(ban);
 132
 133   /* Don't set our ban if something encloses it */
 134   for (cbp2=cp->bans;cbp2;cbp2=cbp2->next) {
 135     if (banoverlap(cbp2, cbp)) {
 136       /* This ban overlaps the one we are adding.  Abort. */
 137       freechanban(cbp);
 138       return 0;
 139     }
 140   }
 141
 142   /* Remove enclosed bans first */
 143   for (cbh=&(cp->bans);*cbh;) {
 144     if (banoverlap(cbp,*cbh)) {
 145       cbp2=(*cbh);
 146       (*cbh)=cbp2->next;
 147       freechanban(cbp2);
 148       /* Break out of the loop if we just deleted the last ban */
 149       if ((*cbh)==NULL) {
 150         break;
 151       }
 152     } else {
 153       cbh=(chanban **)&((*cbh)->next);
 154     }
 155   }
 156
 157   /* Now set the new ban */
 158   cbp->next=(struct chanban *)cp->bans;
 159   cp->bans=cbp;
 160
 161   return 1;
 162 }
 163
 164 /*
 165  * clearban:
 166  *  Remove the specified ban iff an exact match is found
 167  *  Returns 1 if the ban was cleared, 0 if the ban didn't exist.
 168  *  If "optional" is 0 and the ban didn't exist, flags an error
 169  */
 170
 171 int clearban(channel *cp, const char *ban, int optional) {
 172   chanban **cbh,*cbp,*cbp2;
 173   int found=0;
 174   int i=0;
 175
 176   if (!cp)
 177     return 0;
 178
 179   cbp=makeban(ban);
 180
 181   for (cbh=&(cp->bans);*cbh;cbh=(chanban **)&((*cbh)->next)) {
 182     if (banequal(cbp,*cbh)) {
 183       cbp2=(*cbh);
 184       (*cbh)=cbp2->next;
 185       freechanban(cbp2);
 186       found=1;
 187       break;
 188     }
 189   }
 190
 191   if (!found && !optional) {
 192     Error("channel",ERR_DEBUG,"Couldn't remove ban %s from %s.  Dumping banlist:",ban,cp->index->name->content);
 193     for (cbp2=cp->bans;cbp2;cbp2=cbp2->next) {
 194       Error("channel",ERR_DEBUG,"%s %d %s",cp->index->name->content, i++, bantostringdebug(cbp2));
 195     }
 196   }
 197
 198   freechanban(cbp);
 199
 200   return found;
 201 }
 202
 203 /*
 204  * clearallbans:
 205  *  Just free all the bans on the channel
 206  */
 207
 208 void clearallbans(channel *cp) {
 209   chanban *cbp,*ncbp;
 210
 211   for (cbp=cp->bans;cbp;cbp=ncbp) {
 212     ncbp=(chanban *)cbp->next;
 213     freechanban(cbp);
 214   }
 215
 216   cp->bans=NULL;
 217 }