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 InterlockedIncrement (&mono_jit_stats.cas_declsec_check);
22 if (method->wrapper_type == MONO_WRAPPER_MANAGED_TO_NATIVE || method->wrapper_type == MONO_WRAPPER_MANAGED_TO_MANAGED) {
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 MonoMethodCasInfo *info = mono_jit_info_get_cas_info (jinfo);
52 /* first find the stack modifiers applied to the method */
53 flags = mono_declsec_flags_from_method (jinfo->method);
54 info->cas_method_assert = (flags & MONO_DECLSEC_FLAG_ASSERT) != 0;
55 info->cas_method_deny = (flags & MONO_DECLSEC_FLAG_DENY) != 0;
56 info->cas_method_permitonly = (flags & MONO_DECLSEC_FLAG_PERMITONLY) != 0;
58 /* then find the stack modifiers applied to the class */
59 flags = mono_declsec_flags_from_class (jinfo->method->klass);
60 info->cas_class_assert = (flags & MONO_DECLSEC_FLAG_ASSERT) != 0;
61 info->cas_class_deny = (flags & MONO_DECLSEC_FLAG_DENY) != 0;
62 info->cas_class_permitonly = (flags & MONO_DECLSEC_FLAG_PERMITONLY) != 0;
67 mono_declsec_create_frame (MonoDomain *domain, MonoJitInfo *jinfo)
69 MonoSecurityFrame *frame = (MonoSecurityFrame*) mono_object_new (domain, mono_defaults.runtimesecurityframe_class);
70 MonoMethodCasInfo *info;
72 info = mono_jit_info_get_cas_info (jinfo);
73 if (info && !info->cas_inited) {
74 if (mono_method_has_declsec (jinfo->method)) {
75 /* Cache the stack modifiers into the MonoJitInfo structure to speed up future stack walks */
76 mono_declsec_cache_stack_modifiers (jinfo);
78 info->cas_inited = TRUE;
81 MONO_OBJECT_SETREF (frame, method, mono_method_get_object (domain, jinfo->method, NULL));
82 MONO_OBJECT_SETREF (frame, domain, domain->domain);
84 /* stack modifiers on methods have priority on (i.e. replaces) modifiers on class */
86 if (info && info->cas_method_assert) {
87 mono_declsec_get_method_action (jinfo->method, SECURITY_ACTION_ASSERT, &frame->assert);
88 } else if (info && info->cas_class_assert) {
89 mono_declsec_get_class_action (jinfo->method->klass, SECURITY_ACTION_ASSERT, &frame->assert);
92 if (info && info->cas_method_deny) {
93 mono_declsec_get_method_action (jinfo->method, SECURITY_ACTION_DENY, &frame->deny);
94 } else if (info && info->cas_class_deny) {
95 mono_declsec_get_class_action (jinfo->method->klass, SECURITY_ACTION_DENY, &frame->deny);
98 if (info && info->cas_method_permitonly) {
99 mono_declsec_get_method_action (jinfo->method, SECURITY_ACTION_PERMITONLY, &frame->permitonly);
100 } else if (info && info->cas_class_permitonly) {
101 mono_declsec_get_class_action (jinfo->method->klass, SECURITY_ACTION_PERMITONLY, &frame->permitonly);
104 /* g_warning ("FRAME %s A(%p,%d) D(%p,%d) PO(%p,%d)",
105 jinfo->method->name, frame->assert.blob, frame->assert.size, frame->deny.blob, frame->deny.size, frame->permitonly.blob,frame->permitonly.size); */
112 * Execute any LinkDemand, NonCasLinkDemand, LinkDemandChoice declarative
113 * security attribute present on the called method or it's class.
115 * @domain The current application domain
116 * @caller The method calling
117 * @callee The called method.
118 * return value: TRUE if a security violation is detection, FALSE otherwise.
120 * Note: The execution is done in managed code in SecurityManager.LinkDemand
123 mono_declsec_linkdemand_standard (MonoDomain *domain, MonoMethod *caller, MonoMethod *callee)
125 MonoDeclSecurityActions linkclass, linkmethod;
127 InterlockedIncrement (&mono_jit_stats.cas_linkdemand);
129 if (mono_declsec_get_linkdemands (callee, &linkclass, &linkmethod)) {
130 MonoAssembly *assembly = mono_image_get_assembly (caller->klass->image);
131 MonoReflectionAssembly *refass = (MonoReflectionAssembly*) mono_assembly_get_object (domain, assembly);
132 MonoSecurityManager *secman = mono_security_manager_get_methods ();
137 args [1] = &linkclass;
138 args [2] = &linkmethod;
140 res = mono_runtime_invoke (secman->linkdemand, NULL, args, NULL);
141 return !(*(MonoBoolean *) mono_object_unbox(res));
147 * Ensure that the restrictions for partially trusted code are satisfied.
149 * @domain The current application domain
150 * @assembly The assembly to query
151 * return value: TRUE if the assembly is runnning at FullTrust, FALSE otherwise.
154 mono_declsec_is_assembly_fulltrust (MonoDomain *domain, MonoAssembly *assembly)
156 if (!MONO_SECMAN_FLAG_INIT (assembly->fulltrust)) {
157 MonoReflectionAssembly *refass = (MonoReflectionAssembly*) mono_assembly_get_object (domain, assembly);
158 MonoSecurityManager *secman = mono_security_manager_get_methods ();
160 if (secman && refass) {
165 res = mono_runtime_invoke (secman->linkdemandfulltrust, NULL, args, NULL);
166 if (*(MonoBoolean *) mono_object_unbox(res)) {
167 /* keep this value cached as it will be used very often */
168 MONO_SECMAN_FLAG_SET_VALUE (assembly->fulltrust, TRUE);
173 MONO_SECMAN_FLAG_SET_VALUE (assembly->fulltrust, FALSE);
177 return MONO_SECMAN_FLAG_GET_VALUE (assembly->fulltrust);
181 * Ensure that the restrictions for partially trusted code are satisfied.
183 * @domain The current application domain
184 * @caller The method calling
185 * @callee The called method
186 * return value: TRUE if a security violation is detected, FALSE otherwise.
188 * If callee's assembly is strongnamed and doesn't have an
189 * [AllowPartiallyTrustedCallers] attribute then we must enforce a LinkDemand
190 * for FullTrust on all public/protected methods on public class.
192 * Note: APTC is only effective on stongnamed assemblies.
195 mono_declsec_linkdemand_aptc (MonoDomain *domain, MonoMethod *caller, MonoMethod *callee)
197 MonoSecurityManager* secman = NULL;
198 MonoAssembly *assembly;
201 InterlockedIncrement (&mono_jit_stats.cas_linkdemand_aptc);
203 /* A - Applicable only if we're calling into *another* assembly */
204 if (caller->klass->image == callee->klass->image)
207 /* B - Applicable if we're calling a public/protected method from a public class */
208 if (!(callee->klass->flags & TYPE_ATTRIBUTE_PUBLIC) || !(callee->flags & FIELD_ATTRIBUTE_PUBLIC))
211 /* C - Applicable if the callee's assembly is strongnamed */
212 if ((mono_image_get_public_key (callee->klass->image, &size) == NULL) || (size < MONO_ECMA_KEY_LENGTH))
215 /* D - the callee's assembly must have [AllowPartiallyTrustedCallers] */
216 assembly = mono_image_get_assembly (callee->klass->image);
217 if (!MONO_SECMAN_FLAG_INIT (assembly->aptc)) {
218 MonoCustomAttrInfo* cinfo = mono_custom_attrs_from_assembly (assembly);
219 gboolean result = FALSE;
220 secman = mono_security_manager_get_methods ();
221 if (secman && cinfo) {
222 /* look for AllowPartiallyTrustedCallersAttribute */
223 result = mono_custom_attrs_has_attr (cinfo, secman->allowpartiallytrustedcallers);
226 mono_custom_attrs_free (cinfo);
227 MONO_SECMAN_FLAG_SET_VALUE (assembly->aptc, result);
230 if (MONO_SECMAN_FLAG_GET_VALUE (assembly->aptc))
233 /* E - the caller's assembly must have full trust permissions */
234 assembly = mono_image_get_assembly (caller->klass->image);
235 if (mono_declsec_is_assembly_fulltrust (domain, assembly))
238 /* g_warning ("FAILURE *** JIT LinkDemand APTC check *** %s.%s calls into %s.%s",
239 caller->klass->name, caller->name, callee->klass->name, callee->name); */
241 return TRUE; /* i.e. throw new SecurityException(); */
245 * Ensure that the restrictions for calling native code are satisfied.
247 * @domain The current application domain
248 * @caller The method calling
249 * @native The native method called
250 * return value: TRUE if a security violation is detected, FALSE otherwise.
252 * Executing Platform Invokes (P/Invoke) is a is a restricted operation.
253 * The security policy must allow (SecurityPermissionFlag.UnmanagedCode)
254 * an assembly to do this.
256 * This LinkDemand case is special because it only needs to call managed
257 * code once per assembly. Further calls on this assembly will use a cached
258 * flag for better performance. This is not done before the first call (e.g.
259 * when loading the assembly) because that would break the lazy policy
260 * evaluation that Mono use (another time saving optimization).
262 * Note: P/Invoke checks are ALWAYS (1) done at JIT time (as a LinkDemand).
263 * They are also checked at runtime, using a Demand (stack walk), unless the
264 * method or it's class has a [SuppressUnmanagedCodeSecurity] attribute.
266 * (1) well as long as the security manager is active (i.e. --security)
269 mono_declsec_linkdemand_pinvoke (MonoDomain *domain, MonoMethod *caller, MonoMethod *native)
271 MonoAssembly *assembly = mono_image_get_assembly (caller->klass->image);
273 InterlockedIncrement (&mono_jit_stats.cas_linkdemand_pinvoke);
275 /* Check for P/Invoke flag for the assembly */
276 if (!MONO_SECMAN_FLAG_INIT (assembly->unmanaged)) {
277 /* Check if we know (and have) or FullTrust status */
278 if (MONO_SECMAN_FLAG_INIT (assembly->fulltrust) && MONO_SECMAN_FLAG_GET_VALUE (assembly->fulltrust)) {
279 /* FullTrust includes UnmanagedCode permission */
280 MONO_SECMAN_FLAG_SET_VALUE (assembly->unmanaged, TRUE);
283 MonoReflectionAssembly *refass = (MonoReflectionAssembly*) mono_assembly_get_object (domain, assembly);
284 MonoSecurityManager* secman = mono_security_manager_get_methods ();
285 if (secman && refass) {
290 res = mono_runtime_invoke (secman->linkdemandunmanaged, NULL, args, NULL);
291 if (*(MonoBoolean *) mono_object_unbox(res)) {
292 MONO_SECMAN_FLAG_SET_VALUE (assembly->unmanaged, TRUE);
298 MONO_SECMAN_FLAG_SET_VALUE (assembly->unmanaged, FALSE);
301 if (MONO_SECMAN_FLAG_GET_VALUE (assembly->unmanaged))
304 /* g_warning ("FAILURE *** JIT LinkDemand P/Invoke check *** %s.%s calls into %s.%s",
305 caller->klass->name, caller->name, native->klass->name, native->name); */
307 return TRUE; /* i.e. throw new SecurityException(); */
311 * Ensure that the restrictions for calling internal calls are satisfied.
313 * @domain The current application domain
314 * @caller The method calling
315 * @icall The internal call method
316 * return value: TRUE if a security violation is detected, FALSE otherwise.
318 * We can't trust the icall flags/iflags as it comes from the assembly
319 * that we may want to restrict and we do not have the public/restricted
320 * information about icalls in the runtime. Actually it is not so bad
321 * as the CLR 2.0 doesn't enforce that restriction anymore.
323 * So we'll limit the icalls to originate from ECMA signed assemblies
324 * (as this is required for partial trust scenarios) - or - assemblies that
328 mono_declsec_linkdemand_icall (MonoDomain *domain, MonoMethod *caller, MonoMethod *icall)
330 MonoAssembly *assembly;
332 InterlockedIncrement (&mono_jit_stats.cas_linkdemand_icall);
334 /* check if the _icall_ is defined inside an ECMA signed assembly */
335 assembly = mono_image_get_assembly (icall->klass->image);
336 if (!MONO_SECMAN_FLAG_INIT (assembly->ecma)) {
338 const char *pk = mono_image_get_public_key (icall->klass->image, &size);
339 MONO_SECMAN_FLAG_SET_VALUE (assembly->ecma, mono_is_ecma_key (pk, size));
342 if (MONO_SECMAN_FLAG_GET_VALUE (assembly->ecma))
345 /* else check if the _calling_ assembly is running at FullTrust */
346 assembly = mono_image_get_assembly (caller->klass->image);
347 return !mono_declsec_is_assembly_fulltrust (domain, assembly);
352 * Before the JIT can link (call) into a method the following security checks
355 * We check that the code has the permission to link when:
356 * 1. the code try to call an internal call;
357 * 2. the code try to p/invoke to unmanaged code;
358 * 3. the code try to call trusted code without being trusted itself -
359 * or without the trusted code permission (APTC);
360 * 4. the code try to call managed code protected by a LinkDemand security
363 * Failures result in a SecurityException being thrown (later in mini code).
365 * Note: Some checks are duplicated in managed code to deal when reflection is
366 * used to call the methods.
369 mono_declsec_linkdemand (MonoDomain *domain, MonoMethod *caller, MonoMethod *callee)
371 guint32 violation = MONO_JIT_SECURITY_OK;
373 /* short-circuit corlib as it is fully trusted (within itself)
374 * and because this cause major recursion headaches */
375 if ((caller->klass->image == mono_defaults.corlib) && (callee->klass->image == mono_defaults.corlib))
378 /* next, the special (implied) linkdemand */
380 if (callee->iflags & METHOD_IMPL_ATTRIBUTE_INTERNAL_CALL) {
381 /* restrict internal calls into the runtime */
382 if (mono_declsec_linkdemand_icall (domain, caller, callee))
383 violation = MONO_JIT_LINKDEMAND_ECMA;
384 } else if (callee->flags & METHOD_ATTRIBUTE_PINVOKE_IMPL) {
385 /* CAS can restrict p/invoke calls with the assembly granted permissions */
386 if (mono_declsec_linkdemand_pinvoke (domain, caller, callee))
387 violation = MONO_JIT_LINKDEMAND_PINVOKE;
391 /* check if we allow partially trusted callers in trusted (signed) assemblies */
392 if (mono_declsec_linkdemand_aptc (domain, caller, callee))
393 violation = MONO_JIT_LINKDEMAND_APTC;
396 /* then the "normal" LinkDemand (only when called method has declarative security) */
397 if (!violation && mono_method_has_declsec (callee)) {
398 /* LinkDemand are ignored for static constructors (ensured by calling mono_method_has_declsec) */
399 if (mono_declsec_linkdemand_standard (domain, caller, callee))
400 violation = MONO_JIT_LINKDEMAND_PERMISSION;
403 /* if (violation) g_warning ("mono_declsec_linkdemand violation reported %d", violation); */