SM: Add compile-time smhax flag, finishing module. (Closes #62)

stratosphere/sm/Makefile

@@ -46,7 +46,7 @@ ARCH	:=	-march=armv8-a -mtune=cortex-a57 -mtp=soft -fPIE
 CFLAGS	:=	-g -Wall -O2 -ffunction-sections \
 			$(ARCH) $(DEFINES)
 
-CFLAGS	+=	$(INCLUDE) -D__SWITCH__
+CFLAGS	+=	$(INCLUDE) -D__SWITCH__ -DSM_ENABLE_SMHAX
 
 CXXFLAGS	:= $(CFLAGS) -fno-rtti -fno-exceptions -std=gnu++17
 

stratosphere/sm/source/sm_registration.cpp

@@ -6,6 +6,10 @@
 static Registration::Process g_process_list[REGISTRATION_LIST_MAX_PROCESS] = {0};
 static Registration::Service g_service_list[REGISTRATION_LIST_MAX_SERVICE] = {0};
 
+static u64 g_initial_process_id_low = 0;
+static u64 g_initial_process_id_high = 0;
+static bool g_determined_initial_process_ids = false;
+
 u64 GetServiceNameLength(u64 service) {
     u64 service_name_len = 0;
     while (service & 0xFF) {
@@ -107,6 +111,30 @@ bool Registration::ValidateSacAgainstRestriction(u8 *r_sac, size_t r_sac_size, u
     return true;
 }
 
+void Registration::CacheInitialProcessIdLimits() {
+    if (g_determined_initial_process_ids) {
+        return;
+    }
+    if (kernelAbove400()) {
+        svcGetSystemInfo(&g_initial_process_id_low, 2, 0, 0);
+        svcGetSystemInfo(&g_initial_process_id_high, 2, 0, 0);
+    } else {
+        g_initial_process_id_low = 0;
+        g_initial_process_id_high = REGISTRATION_INITIAL_PID_MAX;
+    }
+    g_determined_initial_process_ids = true;
+}
+
+bool Registration::IsInitialProcess(u64 pid) {
+    CacheInitialProcessIdLimits();
+    return g_initial_process_id_low <= pid && pid <= g_initial_process_id_high;
+}
+
+u64 Registration::GetInitialProcessId() {
+    CacheInitialProcessIdLimits();
+    return g_initial_process_id_low;
+}
+
 /* Process management. */
 Result Registration::RegisterProcess(u64 pid, u8 *acid_sac, size_t acid_sac_size, u8 *aci0_sac, size_t aci0_sac_size) {
     Registration::Process *proc = GetFreeProcess();
@@ -178,7 +206,7 @@ Result Registration::GetServiceForPid(u64 pid, u64 service, Handle *out) {
         return 0xC15;
     }
     
-    if (pid >= REGISTRATION_PID_BUILTIN_MAX && service != smEncodeName("dbg:m")) {
+    if (!IsInitialProcess(pid)) {
         Registration::Process *proc = GetProcessForPid(pid);
         if (proc == NULL) {
             return 0x415;
@@ -204,7 +232,7 @@ Result Registration::RegisterServiceForPid(u64 pid, u64 service, u64 max_session
         return 0xC15;
     }
     
-    if (pid >= REGISTRATION_PID_BUILTIN_MAX) {
+    if (!IsInitialProcess(pid)) {
         Registration::Process *proc = GetProcessForPid(pid);
         if (proc == NULL) {
             return 0x415;
@@ -288,7 +316,7 @@ Result Registration::UnregisterServiceForPid(u64 pid, u64 service) {
         return 0xE15;
     }
 
-    if (target_service->owner_pid != pid) {
+    if (!IsInitialProcess(pid) && target_service->owner_pid != pid) {
         return 0x1015;
     }
     

stratosphere/sm/source/sm_registration.hpp

@@ -4,7 +4,7 @@
 #define REGISTRATION_LIST_MAX_PROCESS (0x40)
 #define REGISTRATION_LIST_MAX_SERVICE (0x100)
 #define REGISTRATION_MAX_SAC_SIZE (0x200)
-#define REGISTRATION_PID_BUILTIN_MAX 0x50
+#define REGISTRATION_INITIAL_PID_MAX 0x50
 
 class Registration {
     public:
@@ -27,6 +27,9 @@ class Registration {
         static Registration::Service *GetFreeService();
         static bool IsValidForSac(u8 *sac, size_t sac_size, u64 service, bool is_host);
         static bool ValidateSacAgainstRestriction(u8 *r_sac, size_t r_sac_size, u8 *sac, size_t sac_size);
+        static void CacheInitialProcessIdLimits();
+        static bool IsInitialProcess(u64 pid);
+        static u64 GetInitialProcessId();
         
         /* Process management. */
         static Result RegisterProcess(u64 pid, u8 *acid_sac, size_t acid_sac_size, u8 *aci0_sac, size_t aci0_sac_size);

stratosphere/sm/source/sm_user_service.cpp

@@ -39,6 +39,11 @@ std::tuple<Result> UserService::initialize(PidDescriptor pid) {
 std::tuple<Result, MovedHandle> UserService::get_service(u64 service) {
     Handle session_h = 0;
     Result rc = 0x415;
+#ifdef SM_ENABLE_SMHAX
+    if (!this->has_initialized) {
+        rc = Registration::GetServiceForPid(Registration::GetInitialProcessId(), service, &session_h);
+    }
+#endif
     if (this->has_initialized) {
         rc = Registration::GetServiceForPid(this->pid, service, &session_h);
     }
@@ -58,6 +63,11 @@ std::tuple<Result, MovedHandle> UserService::deferred_get_service(u64 service) {
 std::tuple<Result, MovedHandle> UserService::register_service(u64 service, u8 is_light, u32 max_sessions) {
     Handle service_h = 0;
     Result rc = 0x415;
+#ifdef SM_ENABLE_SMHAX
+    if (!this->has_initialized) {
+        rc = Registration::RegisterServiceForPid(Registration::GetInitialProcessId(), service, max_sessions, is_light != 0, &service_h);
+    }
+#endif
     if (this->has_initialized) {
         rc = Registration::RegisterServiceForPid(this->pid, service, max_sessions, is_light != 0, &service_h);
     }
@@ -66,6 +76,11 @@ std::tuple<Result, MovedHandle> UserService::register_service(u64 service, u8 is
 
 std::tuple<Result> UserService::unregister_service(u64 service) {
     Result rc = 0x415;
+#ifdef SM_ENABLE_SMHAX
+    if (!this->has_initialized) {
+        rc = Registration::UnregisterServiceForPid(Registration::GetInitialProcessId(), service);
+    }
+#endif
     if (this->has_initialized) {
         rc = Registration::UnregisterServiceForPid(this->pid, service);
     }