From 0493935691e925ae137af7636fa15befa76c8b45 Mon Sep 17 00:00:00 2001 From: Eamon Walsh Date: Mon, 31 Aug 2009 21:20:53 -0400 Subject: xselinux: Factor out some dynamic array code into common helpers. Signed-off-by: Eamon Walsh --- Xext/xselinux_label.c | 173 +++++++++++++++++++++++++++----------------------- 1 file changed, 95 insertions(+), 78 deletions(-) diff --git a/Xext/xselinux_label.c b/Xext/xselinux_label.c index 7ec10ff86..239536cf3 100644 --- a/Xext/xselinux_label.c +++ b/Xext/xselinux_label.c @@ -32,21 +32,60 @@ typedef struct { SELinuxObjectRec sel; } SELinuxAtomRec; +/* dynamic array */ +typedef struct { + unsigned size; + void **array; +} SELinuxArrayRec; + /* labeling handle */ static struct selabel_handle *label_hnd; /* Array of object classes indexed by resource type */ -static security_class_t *knownTypes; -static unsigned numKnownTypes; - +SELinuxArrayRec arr_types; /* Array of event SIDs indexed by event type */ -static security_id_t *knownEvents; -static unsigned numKnownEvents; - +SELinuxArrayRec arr_events; /* Array of property and selection SID structures */ -static SELinuxAtomRec *knownAtoms; -static unsigned numKnownAtoms; +SELinuxArrayRec arr_atoms; + +/* + * Dynamic array helpers + */ +static void * +SELinuxArrayGet(SELinuxArrayRec *rec, unsigned key) +{ + return (rec->size > key) ? rec->array[key] : 0; +} + +static int +SELinuxArraySet(SELinuxArrayRec *rec, unsigned key, void *val) +{ + if (key >= rec->size) { + /* Need to increase size of array */ + rec->array = xrealloc(rec->array, (key + 1) * sizeof(val)); + if (!rec->array) + return FALSE; + memset(rec->array + rec->size, 0, (key - rec->size + 1) * sizeof(val)); + rec->size = key + 1; + } + + rec->array[key] = val; + return TRUE; +} +static void +SELinuxArrayFree(SELinuxArrayRec *rec, int free_elements) +{ + if (free_elements) { + unsigned i = rec->size; + while (i) + xfree(rec->array[--i]); + } + + xfree(rec->array); + rec->size = 0; + rec->array = NULL; +} /* * Looks up a name in the selection or property mappings @@ -87,26 +126,23 @@ SELinuxAtomToSIDLookup(Atom atom, SELinuxObjectRec *obj, int map, int polymap) int SELinuxAtomToSID(Atom atom, int prop, SELinuxObjectRec **obj_rtn) { + SELinuxAtomRec *rec; 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) + rec = SELinuxArrayGet(&arr_atoms, atom); + if (!rec) { + rec = xcalloc(1, sizeof(SELinuxAtomRec)); + if (!rec || !SELinuxArraySet(&arr_atoms, atom, rec)) return BadAlloc; - memset(knownAtoms + numKnownAtoms, 0, - (atom - numKnownAtoms + 1) * size); - numKnownAtoms = atom + 1; } if (prop) { - obj = &knownAtoms[atom].prp; + obj = &rec->prp; map = SELABEL_X_PROP; polymap = SELABEL_X_POLYPROP; } else { - obj = &knownAtoms[atom].sel; + obj = &rec->sel; map = SELABEL_X_SELN; polymap = SELABEL_X_POLYSELN; } @@ -218,36 +254,33 @@ SELinuxEventToSID(unsigned type, security_id_t sid_of_window, SELinuxObjectRec *sid_return) { const char *name = LookupEventName(type); + security_id_t sid; security_context_t ctx; 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]) { + sid = SELinuxArrayGet(&arr_events, type); + if (!sid) { /* Look in the mappings of event names to contexts */ if (selabel_lookup_raw(label_hnd, &ctx, 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_raw(ctx, knownEvents + type) < 0) { + if (avc_context_to_sid_raw(ctx, &sid) < 0) { ErrorF("SELinux: a context_to_SID_raw call failed!\n"); + freecon(ctx); return BadAlloc; } freecon(ctx); + /* Cache the SID value */ + if (!SELinuxArraySet(&arr_events, type, sid)) { + sidput(sid); + return BadAlloc; + } } /* Perform a transition to obtain the final SID */ - if (avc_compute_create(sid_of_window, knownEvents[type], SECCLASS_X_EVENT, + if (avc_compute_create(sid_of_window, sid, SECCLASS_X_EVENT, &sid_return->sid) < 0) { ErrorF("SELinux: a compute_create call failed!\n"); return BadValue; @@ -282,44 +315,36 @@ SELinuxExtensionToSID(const char *name, security_id_t *sid_rtn) 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; - } + void *tmp; + + tmp = SELinuxArrayGet(&arr_types, type & TypeMask); + if (!tmp) { + unsigned long class = SECCLASS_X_RESOURCE; + + if (type & RC_DRAWABLE) + class = SECCLASS_X_DRAWABLE; + else if (type == RT_GC) + class = SECCLASS_X_GC; + else if (type == RT_FONT) + class = SECCLASS_X_FONT; + else if (type == RT_CURSOR) + class = SECCLASS_X_CURSOR; + else if (type == RT_COLORMAP) + class = SECCLASS_X_COLORMAP; + else { + /* Need to do a string lookup */ + const char *str = LookupResourceName(type); + if (!strcmp(str, "PICTURE")) + class = SECCLASS_X_DRAWABLE; + else if (!strcmp(str, "GLYPHSET")) + class = SECCLASS_X_FONT; + } - 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; + tmp = (void *)class; + SELinuxArraySet(&arr_types, type & TypeMask, tmp); } - return knownTypes[type]; + return (security_class_t)(unsigned long)tmp; } security_context_t @@ -350,15 +375,7 @@ SELinuxLabelReset(void) label_hnd = NULL; /* Free local state */ - xfree(knownAtoms); - knownAtoms = NULL; - numKnownAtoms = 0; - - xfree(knownEvents); - knownEvents = NULL; - numKnownEvents = 0; - - xfree(knownTypes); - knownTypes = NULL; - numKnownTypes = 0; + SELinuxArrayFree(&arr_types, 0); + SELinuxArrayFree(&arr_events, 0); + SELinuxArrayFree(&arr_atoms, 1); } -- cgit v1.2.3