2 * declsec.c: Declarative Security support
5 * Sebastien Pouliot <sebastien@ximian.com>
7 * Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
14 * Does the methods (or it's class) as any declarative security attribute ?
15 * Is so are they applicable ? (e.g. static class constructor)
18 mono_method_has_declsec (MonoMethod *method)
20 mono_jit_stats.cas_declsec_check++;
22 if (method->wrapper_type == MONO_WRAPPER_MANAGED_TO_NATIVE) {
23 method = mono_marshal_method_from_wrapper (method);
26 } else if (method->wrapper_type != MONO_WRAPPER_NONE)
29 if ((method->klass->flags & TYPE_ATTRIBUTE_HAS_SECURITY) || (method->flags & METHOD_ATTRIBUTE_HAS_SECURITY)) {
30 /* ignore static constructors */
31 if (strcmp (method->name, ".cctor"))
39 * Fill actions for the specific index (which may either be an encoded class token or
40 * an encoded method token) from the metadata image.
41 * Returns TRUE if some actions requiring code generation are present, FALSE otherwise.
44 mono_declsec_cache_stack_modifiers (MonoJitInfo *jinfo)
46 /* first find the stack modifiers applied to the method */
47 guint32 flags = mono_declsec_flags_from_method (jinfo->method);
48 jinfo->cas_method_assert = (flags & MONO_DECLSEC_FLAG_ASSERT) != 0;
49 jinfo->cas_method_deny = (flags & MONO_DECLSEC_FLAG_DENY) != 0;
50 jinfo->cas_method_permitonly = (flags & MONO_DECLSEC_FLAG_PERMITONLY) != 0;
52 /* then find the stack modifiers applied to the class */
53 flags = mono_declsec_flags_from_class (jinfo->method->klass);
54 jinfo->cas_class_assert = (flags & MONO_DECLSEC_FLAG_ASSERT) != 0;
55 jinfo->cas_class_deny = (flags & MONO_DECLSEC_FLAG_DENY) != 0;
56 jinfo->cas_class_permitonly = (flags & MONO_DECLSEC_FLAG_PERMITONLY) != 0;
61 mono_declsec_create_frame (MonoDomain *domain, MonoJitInfo *jinfo)
63 MonoSecurityFrame *frame = (MonoSecurityFrame*) mono_object_new (domain, mono_defaults.runtimesecurityframe_class);
65 if (!jinfo->cas_inited) {
66 if (mono_method_has_declsec (jinfo->method)) {
67 /* Cache the stack modifiers into the MonoJitInfo structure to speed up future stack walks */
68 mono_declsec_cache_stack_modifiers (jinfo);
70 jinfo->cas_inited = TRUE;
73 frame->method = mono_method_get_object (domain, jinfo->method, NULL);
75 /* stack modifiers on methods have priority on (i.e. replaces) modifiers on class */
77 if (jinfo->cas_method_assert) {
78 mono_declsec_get_method_action (jinfo->method, SECURITY_ACTION_ASSERT, &frame->assert);
79 } else if (jinfo->cas_class_assert) {
80 mono_declsec_get_class_action (jinfo->method->klass, SECURITY_ACTION_ASSERT, &frame->assert);
83 if (jinfo->cas_method_deny) {
84 mono_declsec_get_method_action (jinfo->method, SECURITY_ACTION_DENY, &frame->deny);
85 } else if (jinfo->cas_class_deny) {
86 mono_declsec_get_class_action (jinfo->method->klass, SECURITY_ACTION_DENY, &frame->deny);
89 if (jinfo->cas_method_permitonly) {
90 mono_declsec_get_method_action (jinfo->method, SECURITY_ACTION_PERMITONLY, &frame->permitonly);
91 } else if (jinfo->cas_class_permitonly) {
92 mono_declsec_get_class_action (jinfo->method->klass, SECURITY_ACTION_PERMITONLY, &frame->permitonly);
95 /* g_warning ("FRAME %s A(%p,%d) D(%p,%d) PO(%p,%d)",
96 jinfo->method->name, frame->assert.blob, frame->assert.size, frame->deny.blob, frame->deny.size, frame->permitonly.blob,frame->permitonly.size); */
103 * Execute any LinkDemand, NonCasLinkDemand, LinkDemandChoice declarative
104 * security attribute present on the called method or it's class.
106 * @domain The current application domain
107 * @caller The method calling
108 * @callee The called method.
109 * return value: TRUE if a security violation is detection, FALSE otherwise.
111 * Note: The execution is done in managed code in SecurityManager.LinkDemand
114 mono_declsec_linkdemand_standard (MonoDomain *domain, MonoMethod *caller, MonoMethod *callee)
116 MonoDeclSecurityActions linkclass, linkmethod;
118 mono_jit_stats.cas_linkdemand++;
120 if (mono_declsec_get_linkdemands (callee, &linkclass, &linkmethod)) {
121 MonoAssembly *assembly = mono_image_get_assembly (caller->klass->image);
122 MonoReflectionAssembly *refass = (MonoReflectionAssembly*) mono_assembly_get_object (domain, assembly);
123 MonoSecurityManager *secman = mono_security_manager_get_methods ();
128 args [1] = &linkclass;
129 args [2] = &linkmethod;
131 res = mono_runtime_invoke (secman->linkdemand, NULL, args, NULL);
132 return !(*(MonoBoolean *) mono_object_unbox(res));
138 * Ensure that the restrictions for partially trusted code are satisfied.
140 * @domain The current application domain
141 * @assembly The assembly to query
142 * return value: TRUE if the assembly is runnning at FullTrust, FALSE otherwise.
145 mono_declsec_is_assembly_fulltrust (MonoDomain *domain, MonoAssembly *assembly)
147 if (!MONO_SECMAN_FLAG_INIT (assembly->fulltrust)) {
148 MonoReflectionAssembly *refass = (MonoReflectionAssembly*) mono_assembly_get_object (domain, assembly);
149 MonoSecurityManager *secman = mono_security_manager_get_methods ();
151 if (secman && refass) {
156 res = mono_runtime_invoke (secman->linkdemandfulltrust, NULL, args, NULL);
157 if (*(MonoBoolean *) mono_object_unbox(res)) {
158 /* keep this value cached as it will be used very often */
159 MONO_SECMAN_FLAG_SET_VALUE (assembly->fulltrust, TRUE);
164 MONO_SECMAN_FLAG_SET_VALUE (assembly->fulltrust, FALSE);
168 return MONO_SECMAN_FLAG_GET_VALUE (assembly->fulltrust);
172 * Ensure that the restrictions for partially trusted code are satisfied.
174 * @domain The current application domain
175 * @caller The method calling
176 * @callee The called method
177 * return value: TRUE if a security violation is detection, FALSE otherwise.
179 * If callee's assembly is strongnamed and doesn't have an
180 * [AllowPartiallyTrustedCallers] attribute then we must enforce a LinkDemand
181 * for FullTrust on all public/protected methods on public class.
183 * Note: APTC is only effective on stongnamed assemblies.
186 mono_declsec_linkdemand_aptc (MonoDomain *domain, MonoMethod *caller, MonoMethod *callee)
188 MonoSecurityManager* secman = NULL;
189 MonoAssembly *assembly;
192 mono_jit_stats.cas_linkdemand_aptc++;
194 /* A - Applicable only if we're calling into *another* assembly */
195 if (caller->klass->image == callee->klass->image)
198 /* B - Applicable if we're calling a public/protected method from a public class */
199 if (!(callee->klass->flags & TYPE_ATTRIBUTE_PUBLIC) || !(callee->flags & FIELD_ATTRIBUTE_PUBLIC))
202 /* C - Applicable if the callee's assembly is strongnamed */
203 if ((mono_image_get_public_key (callee->klass->image, &size) == NULL) || (size < MONO_ECMA_KEY_LENGTH))
206 /* D - the callee's assembly must have [AllowPartiallyTrustedCallers] */
207 assembly = mono_image_get_assembly (callee->klass->image);
208 if (!MONO_SECMAN_FLAG_INIT (assembly->aptc)) {
209 MonoCustomAttrInfo* cinfo = mono_custom_attrs_from_assembly (assembly);
210 gboolean result = FALSE;
211 secman = mono_security_manager_get_methods ();
212 if (secman && cinfo) {
213 /* look for AllowPartiallyTrustedCallersAttribute */
214 result = mono_custom_attrs_has_attr (cinfo, secman->allowpartiallytrustedcallers);
216 MONO_SECMAN_FLAG_SET_VALUE (assembly->aptc, result);
219 if (MONO_SECMAN_FLAG_GET_VALUE (assembly->aptc))
222 /* E - the caller's assembly must have full trust permissions */
223 if (mono_declsec_is_assembly_fulltrust (domain, assembly))
226 /* g_warning ("FAILURE *** JIT LinkDemand APTC check *** %s.%s calls into %s.%s",
227 caller->klass->name, caller->name, callee->klass->name, callee->name); */
229 return TRUE; /* i.e. throw new SecurityException(); */
233 * Ensure that the restrictions for calling native code are satisfied.
235 * @domain The current application domain
236 * @caller The method calling
237 * @native The native method called
238 * return value: TRUE if a security violation is detection, FALSE otherwise.
240 * Executing Platform Invokes (P/Invoke) is a is a restricted operation.
241 * The security policy must allow (SecurityPermissionFlag.UnmanagedCode)
242 * an assembly to do this.
244 * This LinkDemand case is special because it only needs to call managed
245 * code once per assembly. Further calls on this assembly will use a cached
246 * flag for better performance. This is not done before the first call (e.g.
247 * when loading the assembly) because that would break the lazy policy
248 * evaluation that Mono use (another time saving optimization).
250 * Note: P/Invoke checks are ALWAYS (1) done at JIT time (as a LinkDemand).
251 * They are also checked at runtime, using a Demand (stack walk), unless the
252 * method or it's class has a [SuppressUnmanagedCodeSecurity] attribute.
254 * (1) well as long as the security manager is active (i.e. --security)
257 mono_declsec_linkdemand_pinvoke (MonoDomain *domain, MonoMethod *caller, MonoMethod *native)
259 MonoAssembly *assembly = mono_image_get_assembly (caller->klass->image);
261 mono_jit_stats.cas_linkdemand_pinvoke++;
263 /* Check for P/Invoke flag for the assembly */
264 if (!MONO_SECMAN_FLAG_INIT (assembly->unmanaged)) {
265 /* Check if we know (and have) or FullTrust status */
266 if (MONO_SECMAN_FLAG_INIT (assembly->fulltrust) && MONO_SECMAN_FLAG_GET_VALUE (assembly->fulltrust)) {
267 /* FullTrust includes UnmanagedCode permission */
268 MONO_SECMAN_FLAG_SET_VALUE (assembly->unmanaged, TRUE);
270 MonoReflectionAssembly *refass = (MonoReflectionAssembly*) mono_assembly_get_object (domain, assembly);
271 MonoSecurityManager* secman = mono_security_manager_get_methods ();
272 if (secman && refass) {
277 res = mono_runtime_invoke (secman->linkdemandunmanaged, NULL, args, NULL);
278 if (*(MonoBoolean *) mono_object_unbox(res)) {
279 MONO_SECMAN_FLAG_SET_VALUE (assembly->unmanaged, TRUE);
285 MONO_SECMAN_FLAG_SET_VALUE (assembly->unmanaged, FALSE);
288 if (MONO_SECMAN_FLAG_GET_VALUE (assembly->unmanaged))
291 /* g_warning ("FAILURE *** JIT LinkDemand P/Invoke check *** %s.%s calls into %s.%s",
292 caller->klass->name, caller->name, native->klass->name, native->name); */
294 return TRUE; /* i.e. throw new SecurityException(); */
298 * Ensure that the restrictions for calling internal calls are satisfied.
300 * @domain The current application domain
301 * @caller The method calling
302 * @icall The internal call method
303 * return value: TRUE if a security violation is detection, FALSE otherwise.
305 * We can't trust the icall flags/iflags as it comes from the assembly
306 * that we may want to restrict and we do not have the public/restricted
307 * information about icalls in the runtime. Actually it is not so bad
308 * as the CLR 2.0 doesn't enforce that restriction anymore.
310 * So we'll limit the icalls to originate from ECMA signed assemblies
311 * (as this is required for partial trust scenarios) - or - assemblies that
315 mono_declsec_linkdemand_icall (MonoDomain *domain, MonoMethod *caller, MonoMethod *icall)
317 MonoAssembly *assembly;
319 mono_jit_stats.cas_linkdemand_icall++;
321 /* check if the _icall_ is defined inside an ECMA signed assembly */
322 assembly = mono_image_get_assembly (icall->klass->image);
323 if (!MONO_SECMAN_FLAG_INIT (assembly->ecma)) {
325 const char *pk = mono_image_get_public_key (icall->klass->image, &size);
326 MONO_SECMAN_FLAG_SET_VALUE (assembly->ecma, mono_is_ecma_key (pk, size));
329 if (MONO_SECMAN_FLAG_GET_VALUE (assembly->ecma))
332 /* else check if the _calling_ assembly is running at FullTrust */
333 assembly = mono_image_get_assembly (caller->klass->image);
334 return !mono_declsec_is_assembly_fulltrust (domain, assembly);
339 * Before the JIT can link (call) into a method the following security checks
342 * We check that the code has the permission to link when:
343 * 1. the code try to call an internal call;
344 * 2. the code try to p/invoke to unmanaged code;
345 * 3. the code try to call trusted code without being trusted itself -
346 * or without the trusted code permission (APTC);
347 * 4. the code try to call managed code protected by a LinkDemand security
350 * Failures result in a SecurityException being thrown (later in mini code).
352 * Note: Some checks are duplicated in managed code to deal when reflection is
353 * used to call the methods.
356 mono_declsec_linkdemand (MonoDomain *domain, MonoMethod *caller, MonoMethod *callee)
358 guint32 violation = MONO_JIT_SECURITY_OK;
359 /* first, the special (implied) linkdemand */
361 if (callee->iflags & METHOD_IMPL_ATTRIBUTE_INTERNAL_CALL) {
362 /* restrict internal calls into the runtime */
363 if (mono_declsec_linkdemand_icall (domain, caller, callee))
364 violation = MONO_JIT_LINKDEMAND_ECMA;
365 } else if (callee->flags & METHOD_ATTRIBUTE_PINVOKE_IMPL) {
366 /* CAS can restrict p/invoke calls with the assembly granted permissions */
367 if (mono_declsec_linkdemand_pinvoke (domain, caller, callee))
368 violation = MONO_JIT_LINKDEMAND_PINVOKE;
372 /* check if we allow partially trusted callers in trusted (signed) assemblies */
373 if (mono_declsec_linkdemand_aptc (domain, caller, callee))
374 violation = MONO_JIT_LINKDEMAND_APTC;
377 /* then the "normal" LinkDemand (only when called method has declarative security) */
378 if (!violation && mono_method_has_declsec (callee)) {
379 /* LinkDemand are ignored for static constructors (ensured by calling mono_method_has_declsec) */
380 if (mono_declsec_linkdemand_standard (domain, caller, callee))
381 violation = MONO_JIT_LINKDEMAND_PERMISSION;
384 /* if (violation) g_warning ("mono_declsec_linkdemand violation reported %d", violation); */