xserver/Xext/namespace/hook-selection.c

109 lines
3.6 KiB
C

#define HOOK_NAME "selection"
#include <dix-config.h>
#include <stdio.h>
#include "dix/selection_priv.h"
#include "namespace.h"
#include "hooks.h"
static inline const char *stripNS(const char* name) {
if ((!name) || (name[0] != '<'))
return name; // can this ever happen ?
const char *got = strchr(name, '>');
if (!got)
return name;
return ++got;
}
/*
* This hook is rewriting the client visible selection names to internally used,
* per namespace ones. Whenever a client is asking for a selection, it's name
* is replaced by a namespaced one, e.g. asking for "PRIMARY" while being in
* namespace "foo" will become "<foo>PRIMARY"
*
* A malicious client could still send specially crafted messages to others,
* asking them to send their selection data to him. This needs to be solved
* separately, by a send hook.
*/
void hookSelectionFilter(CallbackListPtr *pcbl, void *unused, void *calldata)
{
XNS_HOOK_HEAD(SelectionFilterParamRec);
/* no rewrite if client is in root namespace */
if (subj->ns->superPower)
return;
const char *op = "<>";
switch (param->op) {
case SELECTION_FILTER_GETOWNER:
op = "SELECTION_FILTER_GETOWNER";
break;
case SELECTION_FILTER_SETOWNER:
op = "SELECTION_FILTER_SETOWNER";
break;
case SELECTION_FILTER_CONVERT:
op = "SELECTION_FILTER_CONVERT";
break;
case SELECTION_FILTER_EV_REQUEST:
op = "SELECTION_FILTER_EV_REQUEST";
break;
case SELECTION_FILTER_EV_CLEAR:
op = "SELECTION_FILTER_EV_CLEAR";
break;
}
const char *origSelectionName = NameForAtom(param->selection);
char selname[PATH_MAX] = { 0 };
snprintf(selname, sizeof(selname)-1, "<%s>%s", subj->ns->name, origSelectionName);
Atom realSelection = MakeAtom(selname, strlen(selname), TRUE);
switch (param->op) {
case SELECTION_FILTER_GETOWNER:
case SELECTION_FILTER_SETOWNER:
case SELECTION_FILTER_CONVERT:
case SELECTION_FILTER_LISTEN:
XNS_HOOK_LOG("%s origsel=%s (%d) newsel=%s (%d) -- using newsel\n", op,
origSelectionName,
param->selection,
selname,
realSelection);
// TODO: check whether window really belongs to the client
param->selection = realSelection;
break;
case SELECTION_FILTER_NOTIFY:
{
// need to translate back, since we're having the ns-prefixed name here
const char *stripped = stripNS(origSelectionName);
ATOM strippedAtom = MakeAtom(stripped, strlen(stripped), TRUE);
XNS_HOOK_LOG("NOTIFY stripped=\"%s\" atom=%d name=\"%s\n", stripped, strippedAtom, NameForAtom(strippedAtom));
XNS_HOOK_LOG("NOTIFY origID %d origName %s transID %d transName %s strippedName %s atom %d\n",
param->selection,
origSelectionName,
realSelection,
selname,
stripped,
strippedAtom);
param->selection = strippedAtom;
break;
}
// nothing to do here: already having the client visible name
case SELECTION_FILTER_EV_REQUEST:
case SELECTION_FILTER_EV_CLEAR:
XNS_HOOK_LOG("%s origsel=%s (%d) newsel=%s (%d) -- using origsel\n", op,
NameForAtom(param->selection),
param->selection,
selname,
realSelection);
break;
default:
XNS_HOOK_LOG("unknown op: %d selection=%d\n", param->op, param->selection);
break;
}
}