diff options
Diffstat (limited to 'xorg-server/Xext/xace.c')
| -rw-r--r-- | xorg-server/Xext/xace.c | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/xorg-server/Xext/xace.c b/xorg-server/Xext/xace.c new file mode 100644 index 000000000..8a8f8c61d --- /dev/null +++ b/xorg-server/Xext/xace.c @@ -0,0 +1,341 @@ +/************************************************************ + +Author: Eamon Walsh <ewalsh@epoch.ncsc.mil> + +Permission to use, copy, modify, distribute, and sell this software and its +documentation for any purpose is hereby granted without fee, provided that +this permission notice appear in supporting documentation. This permission +notice shall be included in all copies or substantial portions of the +Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN +AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN +CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + +********************************************************/ + +#ifdef HAVE_DIX_CONFIG_H +#include <dix-config.h> +#endif + +#include <stdarg.h> +#include "scrnintstr.h" +#include "extnsionst.h" +#include "pixmapstr.h" +#include "regionstr.h" +#include "gcstruct.h" +#include "xacestr.h" + +CallbackListPtr XaceHooks[XACE_NUM_HOOKS] = {0}; + +/* Special-cased hook functions. Called by Xserver. + */ +int XaceHookDispatch(ClientPtr client, int major) +{ + /* Call the audit begin callback, there is no return value. */ + XaceAuditRec rec = { client, 0 }; + CallCallbacks(&XaceHooks[XACE_AUDIT_BEGIN], &rec); + + if (major < 128) { + /* Call the core dispatch hook */ + XaceCoreDispatchRec rec = { client, Success /* default allow */ }; + CallCallbacks(&XaceHooks[XACE_CORE_DISPATCH], &rec); + return rec.status; + } else { + /* Call the extension dispatch hook */ + ExtensionEntry *ext = GetExtensionEntry(major); + XaceExtAccessRec rec = { client, ext, DixUseAccess, Success }; + if (ext) + CallCallbacks(&XaceHooks[XACE_EXT_DISPATCH], &rec); + /* On error, pretend extension doesn't exist */ + return (rec.status == Success) ? Success : BadRequest; + } +} + +int XaceHookPropertyAccess(ClientPtr client, WindowPtr pWin, + PropertyPtr *ppProp, Mask access_mode) +{ + XacePropertyAccessRec rec = { client, pWin, ppProp, access_mode, Success }; + CallCallbacks(&XaceHooks[XACE_PROPERTY_ACCESS], &rec); + return rec.status; +} + +int XaceHookSelectionAccess(ClientPtr client, + Selection **ppSel, Mask access_mode) +{ + XaceSelectionAccessRec rec = { client, ppSel, access_mode, Success }; + CallCallbacks(&XaceHooks[XACE_SELECTION_ACCESS], &rec); + return rec.status; +} + +void XaceHookAuditEnd(ClientPtr ptr, int result) +{ + XaceAuditRec rec = { ptr, result }; + /* call callbacks, there is no return value. */ + CallCallbacks(&XaceHooks[XACE_AUDIT_END], &rec); +} + +/* Entry point for hook functions. Called by Xserver. + */ +int XaceHook(int hook, ...) +{ + pointer calldata; /* data passed to callback */ + int *prv = NULL; /* points to return value from callback */ + va_list ap; /* argument list */ + va_start(ap, hook); + + /* Marshal arguments for passing to callback. + * Each callback has its own case, which sets up a structure to hold + * the arguments and integer return parameter, or in some cases just + * sets calldata directly to a single argument (with no return result) + */ + switch (hook) + { + case XACE_RESOURCE_ACCESS: { + XaceResourceAccessRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, XID), + va_arg(ap, RESTYPE), + va_arg(ap, pointer), + va_arg(ap, RESTYPE), + va_arg(ap, pointer), + va_arg(ap, Mask), + Success /* default allow */ + }; + calldata = &rec; + prv = &rec.status; + break; + } + case XACE_DEVICE_ACCESS: { + XaceDeviceAccessRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, DeviceIntPtr), + va_arg(ap, Mask), + Success /* default allow */ + }; + calldata = &rec; + prv = &rec.status; + break; + } + case XACE_SEND_ACCESS: { + XaceSendAccessRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, DeviceIntPtr), + va_arg(ap, WindowPtr), + va_arg(ap, xEventPtr), + va_arg(ap, int), + Success /* default allow */ + }; + calldata = &rec; + prv = &rec.status; + break; + } + case XACE_RECEIVE_ACCESS: { + XaceReceiveAccessRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, WindowPtr), + va_arg(ap, xEventPtr), + va_arg(ap, int), + Success /* default allow */ + }; + calldata = &rec; + prv = &rec.status; + break; + } + case XACE_CLIENT_ACCESS: { + XaceClientAccessRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, ClientPtr), + va_arg(ap, Mask), + Success /* default allow */ + }; + calldata = &rec; + prv = &rec.status; + break; + } + case XACE_EXT_ACCESS: { + XaceExtAccessRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, ExtensionEntry*), + DixGetAttrAccess, + Success /* default allow */ + }; + calldata = &rec; + prv = &rec.status; + break; + } + case XACE_SERVER_ACCESS: { + XaceServerAccessRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, Mask), + Success /* default allow */ + }; + calldata = &rec; + prv = &rec.status; + break; + } + case XACE_SCREEN_ACCESS: + case XACE_SCREENSAVER_ACCESS: { + XaceScreenAccessRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, ScreenPtr), + va_arg(ap, Mask), + Success /* default allow */ + }; + calldata = &rec; + prv = &rec.status; + break; + } + case XACE_AUTH_AVAIL: { + XaceAuthAvailRec rec = { + va_arg(ap, ClientPtr), + va_arg(ap, XID) + }; + calldata = &rec; + break; + } + case XACE_KEY_AVAIL: { + XaceKeyAvailRec rec = { + va_arg(ap, xEventPtr), + va_arg(ap, DeviceIntPtr), + va_arg(ap, int) + }; + calldata = &rec; + break; + } + default: { + va_end(ap); + return 0; /* unimplemented hook number */ + } + } + va_end(ap); + + /* call callbacks and return result, if any. */ + CallCallbacks(&XaceHooks[hook], calldata); + return prv ? *prv : Success; +} + +/* XaceCensorImage + * + * Called after pScreen->GetImage to prevent pieces or trusted windows from + * being returned in image data from an untrusted window. + * + * Arguments: + * client is the client doing the GetImage. + * pVisibleRegion is the visible region of the window. + * widthBytesLine is the width in bytes of one horizontal line in pBuf. + * pDraw is the source window. + * x, y, w, h is the rectangle of image data from pDraw in pBuf. + * format is the format of the image data in pBuf: ZPixmap or XYPixmap. + * pBuf is the image data. + * + * Returns: nothing. + * + * Side Effects: + * Any part of the rectangle (x, y, w, h) that is outside the visible + * region of the window will be destroyed (overwritten) in pBuf. + */ +void +XaceCensorImage(client, pVisibleRegion, widthBytesLine, pDraw, x, y, w, h, + format, pBuf) + ClientPtr client; + RegionPtr pVisibleRegion; + long widthBytesLine; + DrawablePtr pDraw; + int x, y, w, h; + unsigned int format; + char * pBuf; +{ + ScreenPtr pScreen; + RegionRec imageRegion; /* region representing x,y,w,h */ + RegionRec censorRegion; /* region to obliterate */ + BoxRec imageBox; + int nRects; + + pScreen = pDraw->pScreen; + + imageBox.x1 = x; + imageBox.y1 = y; + imageBox.x2 = x + w; + imageBox.y2 = y + h; + REGION_INIT(pScreen, &imageRegion, &imageBox, 1); + REGION_NULL(pScreen, &censorRegion); + + /* censorRegion = imageRegion - visibleRegion */ + REGION_SUBTRACT(pScreen, &censorRegion, &imageRegion, pVisibleRegion); + nRects = REGION_NUM_RECTS(&censorRegion); + if (nRects > 0) + { /* we have something to censor */ + GCPtr pScratchGC = NULL; + PixmapPtr pPix = NULL; + xRectangle *pRects = NULL; + Bool failed = FALSE; + int depth = 1; + int bitsPerPixel = 1; + int i; + BoxPtr pBox; + + /* convert region to list-of-rectangles for PolyFillRect */ + + pRects = (xRectangle *)xalloc(nRects * sizeof(xRectangle)); + if (!pRects) + { + failed = TRUE; + goto failSafe; + } + for (pBox = REGION_RECTS(&censorRegion), i = 0; + i < nRects; + i++, pBox++) + { + pRects[i].x = pBox->x1; + pRects[i].y = pBox->y1 - imageBox.y1; + pRects[i].width = pBox->x2 - pBox->x1; + pRects[i].height = pBox->y2 - pBox->y1; + } + + /* use pBuf as a fake pixmap */ + + if (format == ZPixmap) + { + depth = pDraw->depth; + bitsPerPixel = pDraw->bitsPerPixel; + } + + pPix = GetScratchPixmapHeader(pDraw->pScreen, w, h, + depth, bitsPerPixel, + widthBytesLine, (pointer)pBuf); + if (!pPix) + { + failed = TRUE; + goto failSafe; + } + + pScratchGC = GetScratchGC(depth, pPix->drawable.pScreen); + if (!pScratchGC) + { + failed = TRUE; + goto failSafe; + } + + ValidateGC(&pPix->drawable, pScratchGC); + (* pScratchGC->ops->PolyFillRect)(&pPix->drawable, + pScratchGC, nRects, pRects); + + failSafe: + if (failed) + { + /* Censoring was not completed above. To be safe, wipe out + * all the image data so that nothing trusted gets out. + */ + bzero(pBuf, (int)(widthBytesLine * h)); + } + if (pRects) xfree(pRects); + if (pScratchGC) FreeScratchGC(pScratchGC); + if (pPix) FreeScratchPixmapHeader(pPix); + } + REGION_UNINIT(pScreen, &imageRegion); + REGION_UNINIT(pScreen, &censorRegion); +} /* XaceCensorImage */ |