diff options
Diffstat (limited to 'xorg-server/Xext/xselinux.c')
| -rw-r--r-- | xorg-server/Xext/xselinux.c | 2037 |
1 files changed, 2037 insertions, 0 deletions
diff --git a/xorg-server/Xext/xselinux.c b/xorg-server/Xext/xselinux.c new file mode 100644 index 000000000..1d3449b9a --- /dev/null +++ b/xorg-server/Xext/xselinux.c @@ -0,0 +1,2037 @@ +/************************************************************ + +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. + +********************************************************/ + +/* + * Portions of this code copyright (c) 2005 by Trusted Computer Solutions, Inc. + * All rights reserved. + */ + +#ifdef HAVE_DIX_CONFIG_H +#include <dix-config.h> +#endif + +#include <sys/socket.h> +#include <stdio.h> +#include <stdarg.h> + +#include <selinux/selinux.h> +#include <selinux/label.h> +#include <selinux/avc.h> + +#include <libaudit.h> + +#include <X11/Xatom.h> +#include "globals.h" +#include "resource.h" +#include "privates.h" +#include "registry.h" +#include "dixstruct.h" +#include "inputstr.h" +#include "windowstr.h" +#include "propertyst.h" +#include "extnsionst.h" +#include "scrnintstr.h" +#include "selection.h" +#include "xacestr.h" +#include "xselinux.h" +#define XSERV_t +#define TRANS_SERVER +#include <X11/Xtrans/Xtrans.h> +#include "../os/osdep.h" +#include "modinit.h" + + +/* + * Globals + */ + +/* private state keys */ +static DevPrivateKey subjectKey = &subjectKey; +static DevPrivateKey objectKey = &objectKey; +static DevPrivateKey dataKey = &dataKey; + +/* subject state (clients and devices only) */ +typedef struct { + security_id_t sid; + security_id_t dev_create_sid; + security_id_t win_create_sid; + security_id_t sel_create_sid; + security_id_t prp_create_sid; + security_id_t sel_use_sid; + security_id_t prp_use_sid; + struct avc_entry_ref aeref; + char *command; + int privileged; +} SELinuxSubjectRec; + +/* object state */ +typedef struct { + security_id_t sid; + int poly; +} SELinuxObjectRec; + +/* selection and property atom cache */ +typedef struct { + SELinuxObjectRec prp; + SELinuxObjectRec sel; +} SELinuxAtomRec; + +/* audit file descriptor */ +static int audit_fd; + +/* structure passed to auditing callback */ +typedef struct { + ClientPtr client; /* client */ + DeviceIntPtr dev; /* device */ + char *command; /* client's executable path */ + unsigned id; /* resource id, if any */ + int restype; /* resource type, if any */ + int event; /* event type, if any */ + Atom property; /* property name, if any */ + Atom selection; /* selection name, if any */ + char *extension; /* extension name, if any */ +} SELinuxAuditRec; + +/* labeling handle */ +static struct selabel_handle *label_hnd; + +/* whether AVC is active */ +static int avc_active; + +/* atoms for window label properties */ +static Atom atom_ctx; +static Atom atom_client_ctx; + +/* The unlabeled SID */ +static security_id_t unlabeled_sid; + +/* Array of object classes indexed by resource type */ +static security_class_t *knownTypes; +static unsigned numKnownTypes; + +/* Array of event SIDs indexed by event type */ +static security_id_t *knownEvents; +static unsigned numKnownEvents; + +/* Array of property and selection SID structures */ +static SELinuxAtomRec *knownAtoms; +static unsigned numKnownAtoms; + +/* dynamically allocated security classes and permissions */ +static struct security_class_mapping map[] = { + { "x_drawable", { "read", "write", "destroy", "create", "getattr", "setattr", "list_property", "get_property", "set_property", "", "", "list_child", "add_child", "remove_child", "hide", "show", "blend", "override", "", "", "", "", "send", "receive", "", "manage", NULL }}, + { "x_screen", { "", "", "", "", "getattr", "setattr", "saver_getattr", "saver_setattr", "", "", "", "", "", "", "hide_cursor", "show_cursor", "saver_hide", "saver_show", NULL }}, + { "x_gc", { "", "", "destroy", "create", "getattr", "setattr", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "use", NULL }}, + { "x_font", { "", "", "destroy", "create", "getattr", "", "", "", "", "", "", "", "add_glyph", "remove_glyph", "", "", "", "", "", "", "", "", "", "", "use", NULL }}, + { "x_colormap", { "read", "write", "destroy", "create", "getattr", "", "", "", "", "", "", "", "add_color", "remove_color", "", "", "", "", "", "", "install", "uninstall", "", "", "use", NULL }}, + { "x_property", { "read", "write", "destroy", "create", "getattr", "setattr", "", "", "", "", "", "", "", "", "", "", "write", NULL }}, + { "x_selection", { "read", "", "", "setattr", "getattr", "setattr", NULL }}, + { "x_cursor", { "read", "write", "destroy", "create", "getattr", "setattr", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "use", NULL }}, + { "x_client", { "", "", "destroy", "", "getattr", "setattr", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "manage", NULL }}, + { "x_device", { "read", "write", "", "", "getattr", "setattr", "", "", "", "getfocus", "setfocus", "", "", "", "", "", "", "grab", "freeze", "force_cursor", "", "", "", "", "use", "manage", "", "bell", NULL }}, + { "x_server", { "record", "", "", "", "getattr", "setattr", "", "", "", "", "", "", "", "", "", "", "", "grab", "", "", "", "", "", "", "", "manage", "debug", NULL }}, + { "x_extension", { "", "", "", "", "query", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "use", NULL }}, + { "x_event", { "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "send", "receive", NULL }}, + { "x_synthetic_event", { "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "send", "receive", NULL }}, + { "x_resource", { "read", "write", "write", "write", "read", "write", "read", "read", "write", "read", "write", "read", "write", "write", "write", "read", "read", "write", "write", "write", "write", "write", "write", "read", "read", "write", "read", "write", NULL }}, + { NULL } +}; + +/* x_resource "read" bits from the list above */ +#define SELinuxReadMask (DixReadAccess|DixGetAttrAccess|DixListPropAccess| \ + DixGetPropAccess|DixGetFocusAccess|DixListAccess| \ + DixShowAccess|DixBlendAccess|DixReceiveAccess| \ + DixUseAccess|DixDebugAccess) + +/* forward declarations */ +static void SELinuxScreen(CallbackListPtr *, pointer, pointer); + +/* "true" pointer value for use as callback data */ +static pointer truep = (pointer)1; + + +/* + * Support Routines + */ + +/* + * Looks up a name in the selection or property mappings + */ +static int +SELinuxAtomToSIDLookup(Atom atom, SELinuxObjectRec *obj, int map, int polymap) +{ + const char *name = NameForAtom(atom); + security_context_t ctx; + int rc = Success; + + obj->poly = 1; + + /* Look in the mappings of names to contexts */ + if (selabel_lookup(label_hnd, &ctx, name, map) == 0) { + obj->poly = 0; + } else if (errno != ENOENT) { + ErrorF("SELinux: a property label lookup failed!\n"); + return BadValue; + } else if (selabel_lookup(label_hnd, &ctx, name, polymap) < 0) { + ErrorF("SELinux: a property label lookup failed!\n"); + return BadValue; + } + + /* Get a SID for context */ + if (avc_context_to_sid(ctx, &obj->sid) < 0) { + ErrorF("SELinux: a context_to_SID call failed!\n"); + rc = BadAlloc; + } + + freecon(ctx); + return rc; +} + +/* + * Looks up the SID corresponding to the given property or selection atom + */ +static int +SELinuxAtomToSID(Atom atom, int prop, SELinuxObjectRec **obj_rtn) +{ + SELinuxObjectRec *obj; + int rc, map, polymap; + + if (atom >= numKnownAtoms) { + /* Need to increase size of atoms array */ + unsigned size = sizeof(SELinuxAtomRec); + knownAtoms = xrealloc(knownAtoms, (atom + 1) * size); + if (!knownAtoms) + return BadAlloc; + memset(knownAtoms + numKnownAtoms, 0, + (atom - numKnownAtoms + 1) * size); + numKnownAtoms = atom + 1; + } + + if (prop) { + obj = &knownAtoms[atom].prp; + map = SELABEL_X_PROP; + polymap = SELABEL_X_POLYPROP; + } else { + obj = &knownAtoms[atom].sel; + map = SELABEL_X_SELN; + polymap = SELABEL_X_POLYSELN; + } + + if (!obj->sid) { + rc = SELinuxAtomToSIDLookup(atom, obj, map, polymap); + if (rc != Success) + goto out; + } + + *obj_rtn = obj; + rc = Success; +out: + return rc; +} + +/* + * Looks up a SID for a selection/subject pair + */ +static int +SELinuxSelectionToSID(Atom selection, SELinuxSubjectRec *subj, + security_id_t *sid_rtn, int *poly_rtn) +{ + int rc; + SELinuxObjectRec *obj; + security_id_t tsid; + + /* Get the default context and polyinstantiation bit */ + rc = SELinuxAtomToSID(selection, 0, &obj); + if (rc != Success) + return rc; + + /* Check for an override context next */ + if (subj->sel_use_sid) { + sidget(tsid = subj->sel_use_sid); + goto out; + } + + sidget(tsid = obj->sid); + + /* Polyinstantiate if necessary to obtain the final SID */ + if (obj->poly) { + sidput(tsid); + if (avc_compute_member(subj->sid, obj->sid, + SECCLASS_X_SELECTION, &tsid) < 0) { + ErrorF("SELinux: a compute_member call failed!\n"); + return BadValue; + } + } +out: + *sid_rtn = tsid; + if (poly_rtn) + *poly_rtn = obj->poly; + return Success; +} + +/* + * Looks up a SID for a property/subject pair + */ +static int +SELinuxPropertyToSID(Atom property, SELinuxSubjectRec *subj, + security_id_t *sid_rtn, int *poly_rtn) +{ + int rc; + SELinuxObjectRec *obj; + security_id_t tsid, tsid2; + + /* Get the default context and polyinstantiation bit */ + rc = SELinuxAtomToSID(property, 1, &obj); + if (rc != Success) + return rc; + + /* Check for an override context next */ + if (subj->prp_use_sid) { + sidget(tsid = subj->prp_use_sid); + goto out; + } + + /* Perform a transition */ + if (avc_compute_create(subj->sid, obj->sid, + SECCLASS_X_PROPERTY, &tsid) < 0) { + ErrorF("SELinux: a compute_create call failed!\n"); + return BadValue; + } + + /* Polyinstantiate if necessary to obtain the final SID */ + if (obj->poly) { + tsid2 = tsid; + if (avc_compute_member(subj->sid, tsid2, + SECCLASS_X_PROPERTY, &tsid) < 0) { + ErrorF("SELinux: a compute_member call failed!\n"); + sidput(tsid2); + return BadValue; + } + sidput(tsid2); + } +out: + *sid_rtn = tsid; + if (poly_rtn) + *poly_rtn = obj->poly; + return Success; +} + +/* + * Looks up the SID corresponding to the given event type + */ +static int +SELinuxEventToSID(unsigned type, security_id_t sid_of_window, + SELinuxObjectRec *sid_return) +{ + const char *name = LookupEventName(type); + security_context_t con; + type &= 127; + + if (type >= numKnownEvents) { + /* Need to increase size of classes array */ + unsigned size = sizeof(security_id_t); + knownEvents = xrealloc(knownEvents, (type + 1) * size); + if (!knownEvents) + return BadAlloc; + memset(knownEvents + numKnownEvents, 0, + (type - numKnownEvents + 1) * size); + numKnownEvents = type + 1; + } + + if (!knownEvents[type]) { + /* Look in the mappings of event names to contexts */ + if (selabel_lookup(label_hnd, &con, name, SELABEL_X_EVENT) < 0) { + ErrorF("SELinux: an event label lookup failed!\n"); + return BadValue; + } + /* Get a SID for context */ + if (avc_context_to_sid(con, knownEvents + type) < 0) { + ErrorF("SELinux: a context_to_SID call failed!\n"); + return BadAlloc; + } + freecon(con); + } + + /* Perform a transition to obtain the final SID */ + if (avc_compute_create(sid_of_window, knownEvents[type], SECCLASS_X_EVENT, + &sid_return->sid) < 0) { + ErrorF("SELinux: a compute_create call failed!\n"); + return BadValue; + } + + return Success; +} + +/* + * Returns the object class corresponding to the given resource type. + */ +static security_class_t +SELinuxTypeToClass(RESTYPE type) +{ + RESTYPE fulltype = type; + type &= TypeMask; + + if (type >= numKnownTypes) { + /* Need to increase size of classes array */ + unsigned size = sizeof(security_class_t); + knownTypes = xrealloc(knownTypes, (type + 1) * size); + if (!knownTypes) + return 0; + memset(knownTypes + numKnownTypes, 0, + (type - numKnownTypes + 1) * size); + numKnownTypes = type + 1; + } + + if (!knownTypes[type]) { + const char *str; + knownTypes[type] = SECCLASS_X_RESOURCE; + + if (fulltype & RC_DRAWABLE) + knownTypes[type] = SECCLASS_X_DRAWABLE; + if (fulltype == RT_GC) + knownTypes[type] = SECCLASS_X_GC; + if (fulltype == RT_FONT) + knownTypes[type] = SECCLASS_X_FONT; + if (fulltype == RT_CURSOR) + knownTypes[type] = SECCLASS_X_CURSOR; + if (fulltype == RT_COLORMAP) + knownTypes[type] = SECCLASS_X_COLORMAP; + + /* Need to do a string lookup */ + str = LookupResourceName(fulltype); + if (!strcmp(str, "PICTURE")) + knownTypes[type] = SECCLASS_X_DRAWABLE; + if (!strcmp(str, "GLYPHSET")) + knownTypes[type] = SECCLASS_X_FONT; + } + + return knownTypes[type]; +} + +/* + * Performs an SELinux permission check. + */ +static int +SELinuxDoCheck(SELinuxSubjectRec *subj, SELinuxObjectRec *obj, + security_class_t class, Mask mode, SELinuxAuditRec *auditdata) +{ + /* serverClient requests OK */ + if (subj->privileged) + return Success; + + auditdata->command = subj->command; + errno = 0; + + if (avc_has_perm(subj->sid, obj->sid, class, mode, &subj->aeref, + auditdata) < 0) { + if (mode == DixUnknownAccess) + return Success; /* DixUnknownAccess requests OK ... for now */ + if (errno == EACCES) + return BadAccess; + ErrorF("SELinux: avc_has_perm: unexpected error %d\n", errno); + return BadValue; + } + + return Success; +} + +/* + * Labels a newly connected client. + */ +static void +SELinuxLabelClient(ClientPtr client) +{ + XtransConnInfo ci = ((OsCommPtr)client->osPrivate)->trans_conn; + int fd = _XSERVTransGetConnectionNumber(ci); + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + security_context_t ctx; + + subj = dixLookupPrivate(&client->devPrivates, subjectKey); + sidput(subj->sid); + obj = dixLookupPrivate(&client->devPrivates, objectKey); + sidput(obj->sid); + + /* Try to get a context from the socket */ + if (fd < 0 || getpeercon(fd, &ctx) < 0) { + /* Otherwise, fall back to a default context */ + if (selabel_lookup(label_hnd, &ctx, NULL, SELABEL_X_CLIENT) < 0) + FatalError("SELinux: failed to look up remote-client context\n"); + } + + /* For local clients, try and determine the executable name */ + if (_XSERVTransIsLocal(ci)) { + struct ucred creds; + socklen_t len = sizeof(creds); + char path[PATH_MAX + 1]; + size_t bytes; + + memset(&creds, 0, sizeof(creds)); + if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &creds, &len) < 0) + goto finish; + + snprintf(path, PATH_MAX + 1, "/proc/%d/cmdline", creds.pid); + fd = open(path, O_RDONLY); + if (fd < 0) + goto finish; + + bytes = read(fd, path, PATH_MAX + 1); + close(fd); + if (bytes <= 0) + goto finish; + + subj->command = xalloc(bytes); + if (!subj->command) + goto finish; + + memcpy(subj->command, path, bytes); + subj->command[bytes - 1] = 0; + } + +finish: + /* Get a SID from the context */ + if (avc_context_to_sid(ctx, &subj->sid) < 0) + FatalError("SELinux: client %d: context_to_sid(%s) failed\n", + client->index, ctx); + + sidget(obj->sid = subj->sid); + freecon(ctx); +} + +/* + * Labels initial server objects. + */ +static void +SELinuxLabelInitial(void) +{ + int i; + XaceScreenAccessRec srec; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + security_context_t ctx; + pointer unused; + + /* Do the serverClient */ + subj = dixLookupPrivate(&serverClient->devPrivates, subjectKey); + obj = dixLookupPrivate(&serverClient->devPrivates, objectKey); + subj->privileged = 1; + sidput(subj->sid); + + /* Use the context of the X server process for the serverClient */ + if (getcon(&ctx) < 0) + FatalError("SELinux: couldn't get context of X server process\n"); + + /* Get a SID from the context */ + if (avc_context_to_sid(ctx, &subj->sid) < 0) + FatalError("SELinux: serverClient: context_to_sid(%s) failed\n", ctx); + + sidget(obj->sid = subj->sid); + freecon(ctx); + + srec.client = serverClient; + srec.access_mode = DixCreateAccess; + srec.status = Success; + + for (i = 0; i < screenInfo.numScreens; i++) { + /* Do the screen object */ + srec.screen = screenInfo.screens[i]; + SELinuxScreen(NULL, NULL, &srec); + + /* Do the default colormap */ + dixLookupResource(&unused, screenInfo.screens[i]->defColormap, + RT_COLORMAP, serverClient, DixCreateAccess); + } +} + +/* + * Labels new resource objects. + */ +static int +SELinuxLabelResource(XaceResourceAccessRec *rec, SELinuxSubjectRec *subj, + SELinuxObjectRec *obj, security_class_t class) +{ + int offset; + security_id_t tsid; + + /* Check for a create context */ + if (rec->rtype == RT_WINDOW && subj->win_create_sid) { + sidget(obj->sid = subj->win_create_sid); + return Success; + } + + if (rec->parent) + offset = dixLookupPrivateOffset(rec->ptype); + + if (rec->parent && offset >= 0) { + /* Use the SID of the parent object in the labeling operation */ + PrivateRec **privatePtr = DEVPRIV_AT(rec->parent, offset); + SELinuxObjectRec *pobj = dixLookupPrivate(privatePtr, objectKey); + tsid = pobj->sid; + } else { + /* Use the SID of the subject */ + tsid = subj->sid; + } + + /* Perform a transition to obtain the final SID */ + if (avc_compute_create(subj->sid, tsid, class, &obj->sid) < 0) { + ErrorF("SELinux: a compute_create call failed!\n"); + return BadValue; + } + + return Success; +} + + +/* + * Libselinux Callbacks + */ + +static int +SELinuxAudit(void *auditdata, + security_class_t class, + char *msgbuf, + size_t msgbufsize) +{ + SELinuxAuditRec *audit = auditdata; + ClientPtr client = audit->client; + char idNum[16], *propertyName, *selectionName; + int major = -1, minor = -1; + + if (client) { + REQUEST(xReq); + if (stuff) { + major = stuff->reqType; + minor = MinorOpcodeOfRequest(client); + } + } + if (audit->id) + snprintf(idNum, 16, "%x", audit->id); + + propertyName = audit->property ? NameForAtom(audit->property) : NULL; + selectionName = audit->selection ? NameForAtom(audit->selection) : NULL; + + return snprintf(msgbuf, msgbufsize, + "%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s", + (major >= 0) ? "request=" : "", + (major >= 0) ? LookupRequestName(major, minor) : "", + audit->command ? " comm=" : "", + audit->command ? audit->command : "", + audit->dev ? " xdevice=\"" : "", + audit->dev ? audit->dev->name : "", + audit->dev ? "\"" : "", + audit->id ? " resid=" : "", + audit->id ? idNum : "", + audit->restype ? " restype=" : "", + audit->restype ? LookupResourceName(audit->restype) : "", + audit->event ? " event=" : "", + audit->event ? LookupEventName(audit->event & 127) : "", + audit->property ? " property=" : "", + audit->property ? propertyName : "", + audit->selection ? " selection=" : "", + audit->selection ? selectionName : "", + audit->extension ? " extension=" : "", + audit->extension ? audit->extension : ""); +} + +static int +SELinuxLog(int type, const char *fmt, ...) +{ + va_list ap; + char buf[MAX_AUDIT_MESSAGE_LENGTH]; + int rc, aut = AUDIT_USER_AVC; + + va_start(ap, fmt); + vsnprintf(buf, MAX_AUDIT_MESSAGE_LENGTH, fmt, ap); + rc = audit_log_user_avc_message(audit_fd, aut, buf, NULL, NULL, NULL, 0); + va_end(ap); + LogMessageVerb(X_WARNING, 0, "%s", buf); + return 0; +} + +/* + * XACE Callbacks + */ + +static void +SELinuxDevice(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XaceDeviceAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + SELinuxAuditRec auditdata = { .client = rec->client, .dev = rec->dev }; + int rc; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + obj = dixLookupPrivate(&rec->dev->devPrivates, objectKey); + + /* If this is a new object that needs labeling, do it now */ + if (rec->access_mode & DixCreateAccess) { + SELinuxSubjectRec *dsubj; + dsubj = dixLookupPrivate(&rec->dev->devPrivates, subjectKey); + + sidput(dsubj->sid); + sidput(obj->sid); + + if (subj->dev_create_sid) { + /* Label the device with the create context */ + sidget(obj->sid = subj->dev_create_sid); + sidget(dsubj->sid = subj->dev_create_sid); + } else { + /* Label the device directly with the process SID */ + sidget(obj->sid = subj->sid); + sidget(dsubj->sid = subj->sid); + } + } + + /* XXX only check read permission on XQueryKeymap */ + /* This is to allow the numerous apps that call XQueryPointer to work */ + if (rec->access_mode & DixReadAccess) { + ClientPtr client = rec->client; + REQUEST(xReq); + if (stuff && stuff->reqType != X_QueryKeymap) { + rec->access_mode &= ~DixReadAccess; + rec->access_mode |= DixGetAttrAccess; + } + } + + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_DEVICE, rec->access_mode, + &auditdata); + if (rc != Success) + rec->status = rc; +} + +static void +SELinuxSend(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XaceSendAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj, ev_sid; + SELinuxAuditRec auditdata = { .client = rec->client, .dev = rec->dev }; + security_class_t class; + int rc, i, type; + + if (rec->dev) + subj = dixLookupPrivate(&rec->dev->devPrivates, subjectKey); + else + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + + obj = dixLookupPrivate(&rec->pWin->devPrivates, objectKey); + + /* Check send permission on window */ + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_DRAWABLE, DixSendAccess, + &auditdata); + if (rc != Success) + goto err; + + /* Check send permission on specific event types */ + for (i = 0; i < rec->count; i++) { + type = rec->events[i].u.u.type; + class = (type & 128) ? SECCLASS_X_FAKEEVENT : SECCLASS_X_EVENT; + + rc = SELinuxEventToSID(type, obj->sid, &ev_sid); + if (rc != Success) + goto err; + + auditdata.event = type; + rc = SELinuxDoCheck(subj, &ev_sid, class, DixSendAccess, &auditdata); + if (rc != Success) + goto err; + } + return; +err: + rec->status = rc; +} + +static void +SELinuxReceive(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XaceReceiveAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj, ev_sid; + SELinuxAuditRec auditdata = { .client = NULL }; + security_class_t class; + int rc, i, type; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + obj = dixLookupPrivate(&rec->pWin->devPrivates, objectKey); + + /* Check receive permission on window */ + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_DRAWABLE, DixReceiveAccess, + &auditdata); + if (rc != Success) + goto err; + + /* Check receive permission on specific event types */ + for (i = 0; i < rec->count; i++) { + type = rec->events[i].u.u.type; + class = (type & 128) ? SECCLASS_X_FAKEEVENT : SECCLASS_X_EVENT; + + rc = SELinuxEventToSID(type, obj->sid, &ev_sid); + if (rc != Success) + goto err; + + auditdata.event = type; + rc = SELinuxDoCheck(subj, &ev_sid, class, DixReceiveAccess, &auditdata); + if (rc != Success) + goto err; + } + return; +err: + rec->status = rc; +} + +static void +SELinuxExtension(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XaceExtAccessRec *rec = calldata; + SELinuxSubjectRec *subj, *serv; + SELinuxObjectRec *obj; + SELinuxAuditRec auditdata = { .client = rec->client }; + int rc; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + obj = dixLookupPrivate(&rec->ext->devPrivates, objectKey); + + /* If this is a new object that needs labeling, do it now */ + /* XXX there should be a separate callback for this */ + if (obj->sid == unlabeled_sid) { + const char *name = rec->ext->name; + security_context_t con; + security_id_t sid; + + serv = dixLookupPrivate(&serverClient->devPrivates, subjectKey); + + /* Look in the mappings of extension names to contexts */ + if (selabel_lookup(label_hnd, &con, name, SELABEL_X_EXT) < 0) { + ErrorF("SELinux: a property label lookup failed!\n"); + rec->status = BadValue; + return; + } + /* Get a SID for context */ + if (avc_context_to_sid(con, &sid) < 0) { + ErrorF("SELinux: a context_to_SID call failed!\n"); + rec->status = BadAlloc; + return; + } + + sidput(obj->sid); + + /* Perform a transition to obtain the final SID */ + if (avc_compute_create(serv->sid, sid, SECCLASS_X_EXTENSION, + &obj->sid) < 0) { + ErrorF("SELinux: a SID transition call failed!\n"); + freecon(con); + rec->status = BadValue; + return; + } + freecon(con); + } + + /* Perform the security check */ + auditdata.extension = rec->ext->name; + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_EXTENSION, rec->access_mode, + &auditdata); + if (rc != Success) + rec->status = rc; +} + +static void +SELinuxSelection(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XaceSelectionAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj, *data; + Selection *pSel = *rec->ppSel; + Atom name = pSel->selection; + Mask access_mode = rec->access_mode; + SELinuxAuditRec auditdata = { .client = rec->client, .selection = name }; + security_id_t tsid; + int rc; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + obj = dixLookupPrivate(&pSel->devPrivates, objectKey); + + /* If this is a new object that needs labeling, do it now */ + if (access_mode & DixCreateAccess) { + sidput(obj->sid); + rc = SELinuxSelectionToSID(name, subj, &obj->sid, &obj->poly); + if (rc != Success) + obj->sid = unlabeled_sid; + access_mode = DixSetAttrAccess; + } + /* If this is a polyinstantiated object, find the right instance */ + else if (obj->poly) { + rc = SELinuxSelectionToSID(name, subj, &tsid, NULL); + if (rc != Success) { + rec->status = rc; + return; + } + while (pSel->selection != name || obj->sid != tsid) { + if ((pSel = pSel->next) == NULL) + break; + obj = dixLookupPrivate(&pSel->devPrivates, objectKey); + } + sidput(tsid); + + if (pSel) + *rec->ppSel = pSel; + else { + rec->status = BadMatch; + return; + } + } + + /* Perform the security check */ + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_SELECTION, access_mode, + &auditdata); + if (rc != Success) + rec->status = rc; + + /* Label the content (advisory only) */ + if (access_mode & DixSetAttrAccess) { + data = dixLookupPrivate(&pSel->devPrivates, dataKey); + sidput(data->sid); + if (subj->sel_create_sid) + sidget(data->sid = subj->sel_create_sid); + else + sidget(data->sid = obj->sid); + } +} + +static void +SELinuxProperty(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XacePropertyAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj, *data; + PropertyPtr pProp = *rec->ppProp; + Atom name = pProp->propertyName; + SELinuxAuditRec auditdata = { .client = rec->client, .property = name }; + security_id_t tsid; + int rc; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + obj = dixLookupPrivate(&pProp->devPrivates, objectKey); + + /* If this is a new object that needs labeling, do it now */ + if (rec->access_mode & DixCreateAccess) { + sidput(obj->sid); + rc = SELinuxPropertyToSID(name, subj, &obj->sid, &obj->poly); + if (rc != Success) { + rec->status = rc; + return; + } + } + /* If this is a polyinstantiated object, find the right instance */ + else if (obj->poly) { + rc = SELinuxPropertyToSID(name, subj, &tsid, NULL); + if (rc != Success) { + rec->status = rc; + return; + } + while (pProp->propertyName != name || obj->sid != tsid) { + if ((pProp = pProp->next) == NULL) + break; + obj = dixLookupPrivate(&pProp->devPrivates, objectKey); + } + sidput(tsid); + + if (pProp) + *rec->ppProp = pProp; + else { + rec->status = BadMatch; + return; + } + } + + /* Perform the security check */ + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_PROPERTY, rec->access_mode, + &auditdata); + if (rc != Success) + rec->status = rc; + + /* Label the content (advisory only) */ + if (rec->access_mode & DixWriteAccess) { + data = dixLookupPrivate(&pProp->devPrivates, dataKey); + sidput(data->sid); + if (subj->prp_create_sid) + sidget(data->sid = subj->prp_create_sid); + else + sidget(data->sid = obj->sid); + } +} + +static void +SELinuxResource(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XaceResourceAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + SELinuxAuditRec auditdata = { .client = rec->client }; + Mask access_mode = rec->access_mode; + PrivateRec **privatePtr; + security_class_t class; + int rc, offset; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + + /* Determine if the resource object has a devPrivates field */ + offset = dixLookupPrivateOffset(rec->rtype); + if (offset < 0) { + /* No: use the SID of the owning client */ + class = SECCLASS_X_RESOURCE; + privatePtr = &clients[CLIENT_ID(rec->id)]->devPrivates; + obj = dixLookupPrivate(privatePtr, objectKey); + } else { + /* Yes: use the SID from the resource object itself */ + class = SELinuxTypeToClass(rec->rtype); + privatePtr = DEVPRIV_AT(rec->res, offset); + obj = dixLookupPrivate(privatePtr, objectKey); + } + + /* If this is a new object that needs labeling, do it now */ + if (access_mode & DixCreateAccess && offset >= 0) { + rc = SELinuxLabelResource(rec, subj, obj, class); + if (rc != Success) { + rec->status = rc; + return; + } + } + + /* Collapse generic resource permissions down to read/write */ + if (class == SECCLASS_X_RESOURCE) { + access_mode = !!(rec->access_mode & SELinuxReadMask); /* rd */ + access_mode |= !!(rec->access_mode & ~SELinuxReadMask) << 1; /* wr */ + } + + /* Perform the security check */ + auditdata.restype = rec->rtype; + auditdata.id = rec->id; + rc = SELinuxDoCheck(subj, obj, class, access_mode, &auditdata); + if (rc != Success) + rec->status = rc; + + /* Perform the background none check on windows */ + if (access_mode & DixCreateAccess && rec->rtype == RT_WINDOW) { + rc = SELinuxDoCheck(subj, obj, class, DixBlendAccess, &auditdata); + if (rc != Success) + ((WindowPtr)rec->res)->forcedBG = TRUE; + } +} + +static void +SELinuxScreen(CallbackListPtr *pcbl, pointer is_saver, pointer calldata) +{ + XaceScreenAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + SELinuxAuditRec auditdata = { .client = rec->client }; + Mask access_mode = rec->access_mode; + int rc; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + obj = dixLookupPrivate(&rec->screen->devPrivates, objectKey); + + /* If this is a new object that needs labeling, do it now */ + if (access_mode & DixCreateAccess) { + sidput(obj->sid); + + /* Perform a transition to obtain the final SID */ + if (avc_compute_create(subj->sid, subj->sid, SECCLASS_X_SCREEN, + &obj->sid) < 0) { + ErrorF("SELinux: a compute_create call failed!\n"); + rec->status = BadValue; + return; + } + } + + if (is_saver) + access_mode <<= 2; + + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_SCREEN, access_mode, &auditdata); + if (rc != Success) + rec->status = rc; +} + +static void +SELinuxClient(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XaceClientAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + SELinuxAuditRec auditdata = { .client = rec->client }; + int rc; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + obj = dixLookupPrivate(&rec->target->devPrivates, objectKey); + + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_CLIENT, rec->access_mode, + &auditdata); + if (rc != Success) + rec->status = rc; +} + +static void +SELinuxServer(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + XaceServerAccessRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + SELinuxAuditRec auditdata = { .client = rec->client }; + int rc; + + subj = dixLookupPrivate(&rec->client->devPrivates, subjectKey); + obj = dixLookupPrivate(&serverClient->devPrivates, objectKey); + + rc = SELinuxDoCheck(subj, obj, SECCLASS_X_SERVER, rec->access_mode, + &auditdata); + if (rc != Success) + rec->status = rc; +} + + +/* + * DIX Callbacks + */ + +static void +SELinuxClientState(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + NewClientInfoRec *pci = calldata; + + switch (pci->client->clientState) { + case ClientStateInitial: + SELinuxLabelClient(pci->client); + break; + + default: + break; + } +} + +static void +SELinuxResourceState(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + ResourceStateInfoRec *rec = calldata; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + WindowPtr pWin; + + if (rec->type != RT_WINDOW) + return; + + pWin = (WindowPtr)rec->value; + subj = dixLookupPrivate(&wClient(pWin)->devPrivates, subjectKey); + + if (subj->sid) { + security_context_t ctx; + int rc = avc_sid_to_context(subj->sid, &ctx); + if (rc < 0) + FatalError("SELinux: Failed to get security context!\n"); + rc = dixChangeWindowProperty(serverClient, + pWin, atom_client_ctx, XA_STRING, 8, + PropModeReplace, strlen(ctx), ctx, FALSE); + if (rc != Success) + FatalError("SELinux: Failed to set label property on window!\n"); + freecon(ctx); + } else + FatalError("SELinux: Unexpected unlabeled client found\n"); + + obj = dixLookupPrivate(&pWin->devPrivates, objectKey); + + if (obj->sid) { + security_context_t ctx; + int rc = avc_sid_to_context(obj->sid, &ctx); + if (rc < 0) + FatalError("SELinux: Failed to get security context!\n"); + rc = dixChangeWindowProperty(serverClient, + pWin, atom_ctx, XA_STRING, 8, + PropModeReplace, strlen(ctx), ctx, FALSE); + if (rc != Success) + FatalError("SELinux: Failed to set label property on window!\n"); + freecon(ctx); + } else + FatalError("SELinux: Unexpected unlabeled window found\n"); +} + + +/* + * DevPrivates Callbacks + */ + +static void +SELinuxSubjectInit(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + PrivateCallbackRec *rec = calldata; + SELinuxSubjectRec *subj = *rec->value; + + sidget(unlabeled_sid); + subj->sid = unlabeled_sid; + + avc_entry_ref_init(&subj->aeref); +} + +static void +SELinuxSubjectFree(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + PrivateCallbackRec *rec = calldata; + SELinuxSubjectRec *subj = *rec->value; + + xfree(subj->command); + + if (avc_active) { + sidput(subj->sid); + sidput(subj->dev_create_sid); + sidput(subj->win_create_sid); + sidput(subj->sel_create_sid); + sidput(subj->prp_create_sid); + } +} + +static void +SELinuxObjectInit(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + PrivateCallbackRec *rec = calldata; + SELinuxObjectRec *obj = *rec->value; + + sidget(unlabeled_sid); + obj->sid = unlabeled_sid; +} + +static void +SELinuxObjectFree(CallbackListPtr *pcbl, pointer unused, pointer calldata) +{ + PrivateCallbackRec *rec = calldata; + SELinuxObjectRec *obj = *rec->value; + + if (avc_active) + sidput(obj->sid); +} + + +/* + * Extension Dispatch + */ + +#define CTX_DEV offsetof(SELinuxSubjectRec, dev_create_sid) +#define CTX_WIN offsetof(SELinuxSubjectRec, win_create_sid) +#define CTX_PRP offsetof(SELinuxSubjectRec, prp_create_sid) +#define CTX_SEL offsetof(SELinuxSubjectRec, sel_create_sid) +#define USE_PRP offsetof(SELinuxSubjectRec, prp_use_sid) +#define USE_SEL offsetof(SELinuxSubjectRec, sel_use_sid) + +typedef struct { + security_context_t octx; + security_context_t dctx; + CARD32 octx_len; + CARD32 dctx_len; + CARD32 id; +} SELinuxListItemRec; + +static int +ProcSELinuxQueryVersion(ClientPtr client) +{ + SELinuxQueryVersionReply rep; + + rep.type = X_Reply; + rep.length = 0; + rep.sequenceNumber = client->sequence; + rep.server_major = SELINUX_MAJOR_VERSION; + rep.server_minor = SELINUX_MINOR_VERSION; + if (client->swapped) { + int n; + swaps(&rep.sequenceNumber, n); + swapl(&rep.length, n); + swaps(&rep.server_major, n); + swaps(&rep.server_minor, n); + } + WriteToClient(client, sizeof(rep), (char *)&rep); + return (client->noClientException); +} + +static int +SELinuxSendContextReply(ClientPtr client, security_id_t sid) +{ + SELinuxGetContextReply rep; + security_context_t ctx = NULL; + int len = 0; + + if (sid) { + if (avc_sid_to_context(sid, &ctx) < 0) + return BadValue; + len = strlen(ctx) + 1; + } + + rep.type = X_Reply; + rep.length = (len + 3) >> 2; + rep.sequenceNumber = client->sequence; + rep.context_len = len; + + if (client->swapped) { + int n; + swapl(&rep.length, n); + swaps(&rep.sequenceNumber, n); + swapl(&rep.context_len, n); + } + + WriteToClient(client, sizeof(SELinuxGetContextReply), (char *)&rep); + WriteToClient(client, len, ctx); + freecon(ctx); + return client->noClientException; +} + +static int +ProcSELinuxSetCreateContext(ClientPtr client, unsigned offset) +{ + PrivateRec **privPtr = &client->devPrivates; + security_id_t *pSid; + security_context_t ctx; + char *ptr; + + REQUEST(SELinuxSetCreateContextReq); + REQUEST_FIXED_SIZE(SELinuxSetCreateContextReq, stuff->context_len); + + ctx = (char *)(stuff + 1); + if (stuff->context_len > 0 && ctx[stuff->context_len - 1]) + return BadLength; + + if (offset == CTX_DEV) { + /* Device create context currently requires manage permission */ + int rc = XaceHook(XACE_SERVER_ACCESS, client, DixManageAccess); + if (rc != Success) + return rc; + privPtr = &serverClient->devPrivates; + } + else if (offset == USE_SEL) { + /* Selection use context currently requires no selections owned */ + Selection *pSel; + for (pSel = CurrentSelections; pSel; pSel = pSel->next) + if (pSel->client == client) + return BadMatch; + } + + ptr = dixLookupPrivate(privPtr, subjectKey); + pSid = (security_id_t *)(ptr + offset); + sidput(*pSid); + *pSid = NULL; + + if (stuff->context_len > 0) { + if (security_check_context(ctx) < 0) + return BadValue; + if (avc_context_to_sid(ctx, pSid) < 0) + return BadValue; + } + return Success; +} + +static int +ProcSELinuxGetCreateContext(ClientPtr client, unsigned offset) +{ + security_id_t *pSid; + char *ptr; + + REQUEST_SIZE_MATCH(SELinuxGetCreateContextReq); + + if (offset == CTX_DEV) + ptr = dixLookupPrivate(&serverClient->devPrivates, subjectKey); + else + ptr = dixLookupPrivate(&client->devPrivates, subjectKey); + + pSid = (security_id_t *)(ptr + offset); + return SELinuxSendContextReply(client, *pSid); +} + +static int +ProcSELinuxSetDeviceContext(ClientPtr client) +{ + security_context_t ctx; + security_id_t sid; + DeviceIntPtr dev; + SELinuxSubjectRec *subj; + SELinuxObjectRec *obj; + int rc; + + REQUEST(SELinuxSetContextReq); + REQUEST_FIXED_SIZE(SELinuxSetContextReq, stuff->context_len); + + ctx = (char *)(stuff + 1); + if (stuff->context_len < 1 || ctx[stuff->context_len - 1]) + return BadLength; + + rc = dixLookupDevice(&dev, stuff->id, client, DixManageAccess); + if (rc != Success) + return rc; + + if (security_check_context(ctx) < 0) + return BadValue; + if (avc_context_to_sid(ctx, &sid) < 0) + return BadValue; + + subj = dixLookupPrivate(&dev->devPrivates, subjectKey); + sidput(subj->sid); + subj->sid = sid; + obj = dixLookupPrivate(&dev->devPrivates, objectKey); + sidput(obj->sid); + sidget(obj->sid = sid); + + return Success; +} + +static int +ProcSELinuxGetDeviceContext(ClientPtr client) +{ + DeviceIntPtr dev; + SELinuxSubjectRec *subj; + int rc; + + REQUEST(SELinuxGetContextReq); + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + + rc = dixLookupDevice(&dev, stuff->id, client, DixGetAttrAccess); + if (rc != Success) + return rc; + + subj = dixLookupPrivate(&dev->devPrivates, subjectKey); + return SELinuxSendContextReply(client, subj->sid); +} + +static int +ProcSELinuxGetWindowContext(ClientPtr client) +{ + WindowPtr pWin; + SELinuxObjectRec *obj; + int rc; + + REQUEST(SELinuxGetContextReq); + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + + rc = dixLookupWindow(&pWin, stuff->id, client, DixGetAttrAccess); + if (rc != Success) + return rc; + + obj = dixLookupPrivate(&pWin->devPrivates, objectKey); + return SELinuxSendContextReply(client, obj->sid); +} + +static int +ProcSELinuxGetPropertyContext(ClientPtr client, pointer privKey) +{ + WindowPtr pWin; + PropertyPtr pProp; + SELinuxObjectRec *obj; + int rc; + + REQUEST(SELinuxGetPropertyContextReq); + REQUEST_SIZE_MATCH(SELinuxGetPropertyContextReq); + + rc = dixLookupWindow(&pWin, stuff->window, client, DixGetPropAccess); + if (rc != Success) + return rc; + + rc = dixLookupProperty(&pProp, pWin, stuff->property, client, + DixGetAttrAccess); + if (rc != Success) + return rc; + + obj = dixLookupPrivate(&pProp->devPrivates, privKey); + return SELinuxSendContextReply(client, obj->sid); +} + +static int +ProcSELinuxGetSelectionContext(ClientPtr client, pointer privKey) +{ + Selection *pSel; + SELinuxObjectRec *obj; + int rc; + + REQUEST(SELinuxGetContextReq); + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + + rc = dixLookupSelection(&pSel, stuff->id, client, DixGetAttrAccess); + if (rc != Success) + return rc; + + obj = dixLookupPrivate(&pSel->devPrivates, privKey); + return SELinuxSendContextReply(client, obj->sid); +} + +static int +ProcSELinuxGetClientContext(ClientPtr client) +{ + ClientPtr target; + SELinuxSubjectRec *subj; + int rc; + + REQUEST(SELinuxGetContextReq); + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + + rc = dixLookupClient(&target, stuff->id, client, DixGetAttrAccess); + if (rc != Success) + return rc; + + subj = dixLookupPrivate(&target->devPrivates, subjectKey); + return SELinuxSendContextReply(client, subj->sid); +} + +static int +SELinuxPopulateItem(SELinuxListItemRec *i, PrivateRec **privPtr, CARD32 id, + int *size) +{ + SELinuxObjectRec *obj = dixLookupPrivate(privPtr, objectKey); + SELinuxObjectRec *data = dixLookupPrivate(privPtr, dataKey); + + if (avc_sid_to_context(obj->sid, &i->octx) < 0) + return BadValue; + if (avc_sid_to_context(data->sid, &i->dctx) < 0) + return BadValue; + + i->id = id; + i->octx_len = (strlen(i->octx) + 4) >> 2; + i->dctx_len = (strlen(i->dctx) + 4) >> 2; + + *size += i->octx_len + i->dctx_len + 3; + return Success; +} + +static void +SELinuxFreeItems(SELinuxListItemRec *items, int count) +{ + int k; + for (k = 0; k < count; k++) { + freecon(items[k].octx); + freecon(items[k].dctx); + } + xfree(items); +} + +static int +SELinuxSendItemsToClient(ClientPtr client, SELinuxListItemRec *items, + int size, int count) +{ + int rc, k, n, pos = 0; + SELinuxListItemsReply rep; + CARD32 *buf; + + buf = xcalloc(size, sizeof(CARD32)); + if (!buf) { + rc = BadAlloc; + goto out; + } + + /* Fill in the buffer */ + for (k = 0; k < count; k++) { + buf[pos] = items[k].id; + if (client->swapped) + swapl(buf + pos, n); + pos++; + + buf[pos] = items[k].octx_len * 4; + if (client->swapped) + swapl(buf + pos, n); + pos++; + + buf[pos] = items[k].dctx_len * 4; + if (client->swapped) + swapl(buf + pos, n); + pos++; + + memcpy((char *)(buf + pos), items[k].octx, strlen(items[k].octx) + 1); + pos += items[k].octx_len; + memcpy((char *)(buf + pos), items[k].dctx, strlen(items[k].dctx) + 1); + pos += items[k].dctx_len; + } + + /* Send reply to client */ + rep.type = X_Reply; + rep.length = size; + rep.sequenceNumber = client->sequence; + rep.count = count; + + if (client->swapped) { + swapl(&rep.length, n); + swaps(&rep.sequenceNumber, n); + swapl(&rep.count, n); + } + + WriteToClient(client, sizeof(SELinuxListItemsReply), (char *)&rep); + WriteToClient(client, size * 4, (char *)buf); + + /* Free stuff and return */ + rc = client->noClientException; + xfree(buf); +out: + SELinuxFreeItems(items, count); + return rc; +} + +static int +ProcSELinuxListProperties(ClientPtr client) +{ + WindowPtr pWin; + PropertyPtr pProp; + SELinuxListItemRec *items; + int rc, count, size, i; + CARD32 id; + + REQUEST(SELinuxGetContextReq); + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + + rc = dixLookupWindow(&pWin, stuff->id, client, DixListPropAccess); + if (rc != Success) + return rc; + + /* Count the number of properties and allocate items */ + count = 0; + for (pProp = wUserProps(pWin); pProp; pProp = pProp->next) + count++; + items = xcalloc(count, sizeof(SELinuxListItemRec)); + if (!items) + return BadAlloc; + + /* Fill in the items and calculate size */ + i = 0; + size = 0; + for (pProp = wUserProps(pWin); pProp; pProp = pProp->next) { + id = pProp->propertyName; + rc = SELinuxPopulateItem(items + i, &pProp->devPrivates, id, &size); + if (rc != Success) { + SELinuxFreeItems(items, count); + return rc; + } + i++; + } + + return SELinuxSendItemsToClient(client, items, size, count); +} + +static int +ProcSELinuxListSelections(ClientPtr client) +{ + Selection *pSel; + SELinuxListItemRec *items; + int rc, count, size, i; + CARD32 id; + + REQUEST_SIZE_MATCH(SELinuxGetCreateContextReq); + + /* Count the number of selections and allocate items */ + count = 0; + for (pSel = CurrentSelections; pSel; pSel = pSel->next) + count++; + items = xcalloc(count, sizeof(SELinuxListItemRec)); + if (!items) + return BadAlloc; + + /* Fill in the items and calculate size */ + i = 0; + size = 0; + for (pSel = CurrentSelections; pSel; pSel = pSel->next) { + id = pSel->selection; + rc = SELinuxPopulateItem(items + i, &pSel->devPrivates, id, &size); + if (rc != Success) { + SELinuxFreeItems(items, count); + return rc; + } + i++; + } + + return SELinuxSendItemsToClient(client, items, size, count); +} + +static int +ProcSELinuxDispatch(ClientPtr client) +{ + REQUEST(xReq); + switch (stuff->data) { + case X_SELinuxQueryVersion: + return ProcSELinuxQueryVersion(client); + case X_SELinuxSetDeviceCreateContext: + return ProcSELinuxSetCreateContext(client, CTX_DEV); + case X_SELinuxGetDeviceCreateContext: + return ProcSELinuxGetCreateContext(client, CTX_DEV); + case X_SELinuxSetDeviceContext: + return ProcSELinuxSetDeviceContext(client); + case X_SELinuxGetDeviceContext: + return ProcSELinuxGetDeviceContext(client); + case X_SELinuxSetWindowCreateContext: + return ProcSELinuxSetCreateContext(client, CTX_WIN); + case X_SELinuxGetWindowCreateContext: + return ProcSELinuxGetCreateContext(client, CTX_WIN); + case X_SELinuxGetWindowContext: + return ProcSELinuxGetWindowContext(client); + case X_SELinuxSetPropertyCreateContext: + return ProcSELinuxSetCreateContext(client, CTX_PRP); + case X_SELinuxGetPropertyCreateContext: + return ProcSELinuxGetCreateContext(client, CTX_PRP); + case X_SELinuxSetPropertyUseContext: + return ProcSELinuxSetCreateContext(client, USE_PRP); + case X_SELinuxGetPropertyUseContext: + return ProcSELinuxGetCreateContext(client, USE_PRP); + case X_SELinuxGetPropertyContext: + return ProcSELinuxGetPropertyContext(client, objectKey); + case X_SELinuxGetPropertyDataContext: + return ProcSELinuxGetPropertyContext(client, dataKey); + case X_SELinuxListProperties: + return ProcSELinuxListProperties(client); + case X_SELinuxSetSelectionCreateContext: + return ProcSELinuxSetCreateContext(client, CTX_SEL); + case X_SELinuxGetSelectionCreateContext: + return ProcSELinuxGetCreateContext(client, CTX_SEL); + case X_SELinuxSetSelectionUseContext: + return ProcSELinuxSetCreateContext(client, USE_SEL); + case X_SELinuxGetSelectionUseContext: + return ProcSELinuxGetCreateContext(client, USE_SEL); + case X_SELinuxGetSelectionContext: + return ProcSELinuxGetSelectionContext(client, objectKey); + case X_SELinuxGetSelectionDataContext: + return ProcSELinuxGetSelectionContext(client, dataKey); + case X_SELinuxListSelections: + return ProcSELinuxListSelections(client); + case X_SELinuxGetClientContext: + return ProcSELinuxGetClientContext(client); + default: + return BadRequest; + } +} + +static int +SProcSELinuxQueryVersion(ClientPtr client) +{ + REQUEST(SELinuxQueryVersionReq); + int n; + + REQUEST_SIZE_MATCH(SELinuxQueryVersionReq); + swaps(&stuff->client_major, n); + swaps(&stuff->client_minor, n); + return ProcSELinuxQueryVersion(client); +} + +static int +SProcSELinuxSetCreateContext(ClientPtr client, unsigned offset) +{ + REQUEST(SELinuxSetCreateContextReq); + int n; + + REQUEST_AT_LEAST_SIZE(SELinuxSetCreateContextReq); + swapl(&stuff->context_len, n); + return ProcSELinuxSetCreateContext(client, offset); +} + +static int +SProcSELinuxSetDeviceContext(ClientPtr client) +{ + REQUEST(SELinuxSetContextReq); + int n; + + REQUEST_AT_LEAST_SIZE(SELinuxSetContextReq); + swapl(&stuff->id, n); + swapl(&stuff->context_len, n); + return ProcSELinuxSetDeviceContext(client); +} + +static int +SProcSELinuxGetDeviceContext(ClientPtr client) +{ + REQUEST(SELinuxGetContextReq); + int n; + + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + swapl(&stuff->id, n); + return ProcSELinuxGetDeviceContext(client); +} + +static int +SProcSELinuxGetWindowContext(ClientPtr client) +{ + REQUEST(SELinuxGetContextReq); + int n; + + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + swapl(&stuff->id, n); + return ProcSELinuxGetWindowContext(client); +} + +static int +SProcSELinuxGetPropertyContext(ClientPtr client, pointer privKey) +{ + REQUEST(SELinuxGetPropertyContextReq); + int n; + + REQUEST_SIZE_MATCH(SELinuxGetPropertyContextReq); + swapl(&stuff->window, n); + swapl(&stuff->property, n); + return ProcSELinuxGetPropertyContext(client, privKey); +} + +static int +SProcSELinuxGetSelectionContext(ClientPtr client, pointer privKey) +{ + REQUEST(SELinuxGetContextReq); + int n; + + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + swapl(&stuff->id, n); + return ProcSELinuxGetSelectionContext(client, privKey); +} + +static int +SProcSELinuxListProperties(ClientPtr client) +{ + REQUEST(SELinuxGetContextReq); + int n; + + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + swapl(&stuff->id, n); + return ProcSELinuxListProperties(client); +} + +static int +SProcSELinuxGetClientContext(ClientPtr client) +{ + REQUEST(SELinuxGetContextReq); + int n; + + REQUEST_SIZE_MATCH(SELinuxGetContextReq); + swapl(&stuff->id, n); + return ProcSELinuxGetClientContext(client); +} + +static int +SProcSELinuxDispatch(ClientPtr client) +{ + REQUEST(xReq); + int n; + + swaps(&stuff->length, n); + + switch (stuff->data) { + case X_SELinuxQueryVersion: + return SProcSELinuxQueryVersion(client); + case X_SELinuxSetDeviceCreateContext: + return SProcSELinuxSetCreateContext(client, CTX_DEV); + case X_SELinuxGetDeviceCreateContext: + return ProcSELinuxGetCreateContext(client, CTX_DEV); + case X_SELinuxSetDeviceContext: + return SProcSELinuxSetDeviceContext(client); + case X_SELinuxGetDeviceContext: + return SProcSELinuxGetDeviceContext(client); + case X_SELinuxSetWindowCreateContext: + return SProcSELinuxSetCreateContext(client, CTX_WIN); + case X_SELinuxGetWindowCreateContext: + return ProcSELinuxGetCreateContext(client, CTX_WIN); + case X_SELinuxGetWindowContext: + return SProcSELinuxGetWindowContext(client); + case X_SELinuxSetPropertyCreateContext: + return SProcSELinuxSetCreateContext(client, CTX_PRP); + case X_SELinuxGetPropertyCreateContext: + return ProcSELinuxGetCreateContext(client, CTX_PRP); + case X_SELinuxSetPropertyUseContext: + return SProcSELinuxSetCreateContext(client, USE_PRP); + case X_SELinuxGetPropertyUseContext: + return ProcSELinuxGetCreateContext(client, USE_PRP); + case X_SELinuxGetPropertyContext: + return SProcSELinuxGetPropertyContext(client, objectKey); + case X_SELinuxGetPropertyDataContext: + return SProcSELinuxGetPropertyContext(client, dataKey); + case X_SELinuxListProperties: + return SProcSELinuxListProperties(client); + case X_SELinuxSetSelectionCreateContext: + return SProcSELinuxSetCreateContext(client, CTX_SEL); + case X_SELinuxGetSelectionCreateContext: + return ProcSELinuxGetCreateContext(client, CTX_SEL); + case X_SELinuxSetSelectionUseContext: + return SProcSELinuxSetCreateContext(client, USE_SEL); + case X_SELinuxGetSelectionUseContext: + return ProcSELinuxGetCreateContext(client, USE_SEL); + case X_SELinuxGetSelectionContext: + return SProcSELinuxGetSelectionContext(client, objectKey); + case X_SELinuxGetSelectionDataContext: + return SProcSELinuxGetSelectionContext(client, dataKey); + case X_SELinuxListSelections: + return ProcSELinuxListSelections(client); + case X_SELinuxGetClientContext: + return SProcSELinuxGetClientContext(client); + default: + return BadRequest; + } +} + + +/* + * Extension Setup / Teardown + */ + +static void +SELinuxResetProc(ExtensionEntry *extEntry) +{ + /* Unregister callbacks */ + DeleteCallback(&ClientStateCallback, SELinuxClientState, NULL); + DeleteCallback(&ResourceStateCallback, SELinuxResourceState, NULL); + + XaceDeleteCallback(XACE_EXT_DISPATCH, SELinuxExtension, NULL); + XaceDeleteCallback(XACE_RESOURCE_ACCESS, SELinuxResource, NULL); + XaceDeleteCallback(XACE_DEVICE_ACCESS, SELinuxDevice, NULL); + XaceDeleteCallback(XACE_PROPERTY_ACCESS, SELinuxProperty, NULL); + XaceDeleteCallback(XACE_SEND_ACCESS, SELinuxSend, NULL); + XaceDeleteCallback(XACE_RECEIVE_ACCESS, SELinuxReceive, NULL); + XaceDeleteCallback(XACE_CLIENT_ACCESS, SELinuxClient, NULL); + XaceDeleteCallback(XACE_EXT_ACCESS, SELinuxExtension, NULL); + XaceDeleteCallback(XACE_SERVER_ACCESS, SELinuxServer, NULL); + XaceDeleteCallback(XACE_SELECTION_ACCESS, SELinuxSelection, NULL); + XaceDeleteCallback(XACE_SCREEN_ACCESS, SELinuxScreen, NULL); + XaceDeleteCallback(XACE_SCREENSAVER_ACCESS, SELinuxScreen, truep); + + /* Tear down SELinux stuff */ + selabel_close(label_hnd); + label_hnd = NULL; + + audit_close(audit_fd); + + avc_destroy(); + avc_active = 0; + + /* Free local state */ + xfree(knownAtoms); + knownAtoms = NULL; + numKnownAtoms = 0; + + xfree(knownEvents); + knownEvents = NULL; + numKnownEvents = 0; + + xfree(knownTypes); + knownTypes = NULL; + numKnownTypes = 0; +} + +void +SELinuxExtensionInit(INITARGS) +{ + ExtensionEntry *extEntry; + struct selinux_opt selabel_option = { SELABEL_OPT_VALIDATE, (char *)1 }; + struct selinux_opt avc_option = { AVC_OPT_SETENFORCE, (char *)0 }; + security_context_t con; + int ret = TRUE; + + /* Check SELinux mode on system */ + if (!is_selinux_enabled()) { + ErrorF("SELinux: Disabled on system, not enabling in X server\n"); + return; + } + + /* Check SELinux mode in configuration file */ + switch(selinuxEnforcingState) { + case SELINUX_MODE_DISABLED: + LogMessage(X_INFO, "SELinux: Disabled in configuration file\n"); + return; + case SELINUX_MODE_ENFORCING: + LogMessage(X_INFO, "SELinux: Configured in enforcing mode\n"); + avc_option.value = (char *)1; + break; + case SELINUX_MODE_PERMISSIVE: + LogMessage(X_INFO, "SELinux: Configured in permissive mode\n"); + avc_option.value = (char *)0; + break; + default: + avc_option.type = AVC_OPT_UNUSED; + break; + } + + /* Set up SELinux stuff */ + selinux_set_callback(SELINUX_CB_LOG, (union selinux_callback)SELinuxLog); + selinux_set_callback(SELINUX_CB_AUDIT, (union selinux_callback)SELinuxAudit); + + if (selinux_set_mapping(map) < 0) { + if (errno == EINVAL) { + ErrorF("SELinux: Invalid object class mapping, disabling SELinux support.\n"); + return; + } + FatalError("SELinux: Failed to set up security class mapping\n"); + } + + if (avc_open(&avc_option, 1) < 0) + FatalError("SELinux: Couldn't initialize SELinux userspace AVC\n"); + avc_active = 1; + + label_hnd = selabel_open(SELABEL_CTX_X, &selabel_option, 1); + if (!label_hnd) + FatalError("SELinux: Failed to open x_contexts mapping in policy\n"); + + if (security_get_initial_context("unlabeled", &con) < 0) + FatalError("SELinux: Failed to look up unlabeled context\n"); + if (avc_context_to_sid(con, &unlabeled_sid) < 0) + FatalError("SELinux: a context_to_SID call failed!\n"); + freecon(con); + + /* Prepare for auditing */ + audit_fd = audit_open(); + if (audit_fd < 0) + FatalError("SELinux: Failed to open the system audit log\n"); + + /* Allocate private storage */ + if (!dixRequestPrivate(subjectKey, sizeof(SELinuxSubjectRec)) || + !dixRequestPrivate(objectKey, sizeof(SELinuxObjectRec)) || + !dixRequestPrivate(dataKey, sizeof(SELinuxObjectRec))) + FatalError("SELinux: Failed to allocate private storage.\n"); + + /* Create atoms for doing window labeling */ + atom_ctx = MakeAtom("_SELINUX_CONTEXT", 16, TRUE); + if (atom_ctx == BAD_RESOURCE) + FatalError("SELinux: Failed to create atom\n"); + atom_client_ctx = MakeAtom("_SELINUX_CLIENT_CONTEXT", 23, TRUE); + if (atom_client_ctx == BAD_RESOURCE) + FatalError("SELinux: Failed to create atom\n"); + + /* Register callbacks */ + ret &= dixRegisterPrivateInitFunc(subjectKey, SELinuxSubjectInit, NULL); + ret &= dixRegisterPrivateDeleteFunc(subjectKey, SELinuxSubjectFree, NULL); + ret &= dixRegisterPrivateInitFunc(objectKey, SELinuxObjectInit, NULL); + ret &= dixRegisterPrivateDeleteFunc(objectKey, SELinuxObjectFree, NULL); + ret &= dixRegisterPrivateInitFunc(dataKey, SELinuxObjectInit, NULL); + ret &= dixRegisterPrivateDeleteFunc(dataKey, SELinuxObjectFree, NULL); + + ret &= AddCallback(&ClientStateCallback, SELinuxClientState, NULL); + ret &= AddCallback(&ResourceStateCallback, SELinuxResourceState, NULL); + + ret &= XaceRegisterCallback(XACE_EXT_DISPATCH, SELinuxExtension, NULL); + ret &= XaceRegisterCallback(XACE_RESOURCE_ACCESS, SELinuxResource, NULL); + ret &= XaceRegisterCallback(XACE_DEVICE_ACCESS, SELinuxDevice, NULL); + ret &= XaceRegisterCallback(XACE_PROPERTY_ACCESS, SELinuxProperty, NULL); + ret &= XaceRegisterCallback(XACE_SEND_ACCESS, SELinuxSend, NULL); + ret &= XaceRegisterCallback(XACE_RECEIVE_ACCESS, SELinuxReceive, NULL); + ret &= XaceRegisterCallback(XACE_CLIENT_ACCESS, SELinuxClient, NULL); + ret &= XaceRegisterCallback(XACE_EXT_ACCESS, SELinuxExtension, NULL); + ret &= XaceRegisterCallback(XACE_SERVER_ACCESS, SELinuxServer, NULL); + ret &= XaceRegisterCallback(XACE_SELECTION_ACCESS, SELinuxSelection, NULL); + ret &= XaceRegisterCallback(XACE_SCREEN_ACCESS, SELinuxScreen, NULL); + ret &= XaceRegisterCallback(XACE_SCREENSAVER_ACCESS, SELinuxScreen, truep); + if (!ret) + FatalError("SELinux: Failed to register one or more callbacks\n"); + + /* Add extension to server */ + extEntry = AddExtension(SELINUX_EXTENSION_NAME, + SELinuxNumberEvents, SELinuxNumberErrors, + ProcSELinuxDispatch, SProcSELinuxDispatch, + SELinuxResetProc, StandardMinorOpcode); + + AddExtensionAlias("Flask", extEntry); + + /* Label objects that were created before we could register ourself */ + SELinuxLabelInitial(); +} |