Mach messages: mach_exc

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osfmk/mach/mach_exc.defs. Listed in the kernel kobject subsystem table, subject to the registration guards and per-slot skips. The destination's typed capability still controls admission. Registration evidence: mig_e.

Reading these entries

IDs are computed from the explicit preprocessing profiles in the catalog guide, counting both routines and skip slots. They are not discovered from a running kernel. Each entry retains all observed names/declaration locations; the displayed fields come from the first non-skipped profile. Alternative declarations can have different fields. simpleroutine is one-way at the MIG interface level.

An interface contract block quotes the adjacent local .defs comment with whitespace normalized. Mechanism paragraphs explain selected implementation decisions. Local body links and call names identify implementation evidence; syntactic call lists are reading aids, not a proof that every listed call executes on every path. Short complete implementation bodies are included where especially useful.

Complete routine and reserved-slot catalog

2405: mach_exception_raise

Deliver a Mach exception with wide exception-code elements and thread/task rights.

Mechanism: For default exception behavior, XNU exports control ports in developer mode or for a corpse, otherwise read ports, and sends the wide exception codes. The local Unix receiver verifies its destination, converts the thread port to a read reference and calls handle_ux_exception; it consumes the supplied task/thread send rights only on success and always drops the converted thread reference. Local path.

Declarations: mach_exception_raise (server64, server32, client64, client32, libsyscall64, sender64, local64).

Fields after preprocessing (server64):

routine mach_exception_raise(
   exception_port : mach_port_t;
   thread : mach_port_t;
   task : mach_port_t;
   exception : exception_type_t;
   code : mach_exception_data_t
   );

Local body: catch_mach_exception_raise. Calls visible in this body include convert_port_to_thread_read, handle_ux_exception, ipc_port_release_send, thread_deallocate.

2406: mach_exception_raise_state

Deliver wide exception codes and thread-state data, accepting replacement state in the reply.

Mechanism: The EXCEPTION_STATE sender obtains architecture state with thread_getstatus_to_user, allocates reply-state storage and sends wide exception codes with a flavor/count. A successful reply is validated through thread_setstatus_from_user, except for corpse notification. The local Unix receiver for this state-only form returns KERN_INVALID_ARGUMENT; a user exception server supplies the useful receiver. Local path.

Declarations: mach_exception_raise_state (server64, server32, client64, client32, libsyscall64, sender64, local64).

Fields after preprocessing (server64):

routine mach_exception_raise_state(
   exception_port : mach_port_t;
   exception : exception_type_t;
   code : mach_exception_data_t, const;
    inout flavor : int;
   old_state : thread_state_t, const;
      out new_state : thread_state_t
   );

Local body: catch_mach_exception_raise_state.

Implementation excerpt:

catch_mach_exception_raise_state(
	__unused mach_port_t                    exception_port,
	__unused exception_type_t               exception,
	__unused const mach_exception_data_t    code,
	__unused mach_msg_type_number_t         codeCnt,
	__unused int                           *flavor,
	__unused const thread_state_t           old_state,
	__unused mach_msg_type_number_t         old_stateCnt,
	__unused thread_state_t                 new_state,
	__unused mach_msg_type_number_t        *new_stateCnt)
{
	return KERN_INVALID_ARGUMENT;
}

2407: mach_exception_raise_state_identity

Deliver wide exception codes, thread/task rights and state, accepting replacement state in the reply.

Mechanism: The state-and-identity sender exports policy-selected task/thread capabilities as well as old thread state, flavor and wide codes. A successful reply is imported through architecture/state validation only when the exception is not EXC_CORPSE_NOTIFY and the exported thread port is IKOT_THREAD_CONTROL; the read-port delivery branch does not import returned state. The in-kernel Unix handler is an invalid-argument stub for this behavior; its presence in the generated exception subsystem does not mean it implements state editing. Local path.

Declarations: mach_exception_raise_state_identity (server64, server32, client64, client32, libsyscall64, sender64, local64).

Fields after preprocessing (server64):

routine mach_exception_raise_state_identity(
   exception_port : mach_port_t;
   thread : mach_port_t;
   task : mach_port_t;
   exception : exception_type_t;
   code : mach_exception_data_t;
    inout flavor : int;
   old_state : thread_state_t;
      out new_state : thread_state_t
   );

Local body: catch_mach_exception_raise_state_identity.

Implementation excerpt:

catch_mach_exception_raise_state_identity(
	__unused mach_port_t                   exception_port,
	__unused mach_port_t                   thread,
	__unused mach_port_t                   task,
	__unused exception_type_t              exception,
	__unused mach_exception_data_t         code,
	__unused mach_msg_type_number_t        codeCnt,
	__unused int                          *flavor,
	__unused thread_state_t                old_state,
	__unused mach_msg_type_number_t        old_stateCnt,
	__unused thread_state_t                new_state,
	__unused mach_msg_type_number_t       *new_stateCnt)
{
	return KERN_INVALID_ARGUMENT;
}

2408: mach_exception_raise_identity_protected

Deliver an exception using a task identity token and thread identifier instead of exposing ordinary control rights.

Mechanism: Creates a task identity token and sends its port plus numeric thread ID instead of exporting task/thread control ports. This behavior requires wide exception codes. A task becoming inactive during identity-token creation is treated specially. The local Unix receiver returns invalid argument; registered external exception servers can implement this protocol. Local path.

Declarations: mach_exception_raise_identity_protected (server64, server32, sender64, local64). Reserved instead in: client64, client32, libsyscall64.

Fields after preprocessing (server64):

routine mach_exception_raise_identity_protected(
   exception_port : mach_port_t;
   thread_id : uint64_t;
   task_id_token_t : mach_port_t;
   exception : exception_type_t;
   code : mach_exception_data_t
   );

Local body: catch_mach_exception_raise_identity_protected.

Implementation excerpt:

catch_mach_exception_raise_identity_protected(
	__unused mach_port_t               exception_port,
	__unused uint64_t                  thread_id,
	__unused mach_port_t               task_id_token,
	__unused exception_type_t          exception,
	__unused mach_exception_data_t     code,
	__unused mach_msg_type_number_t    codeCnt)
{
	return KERN_INVALID_ARGUMENT;
}

2409: mach_exception_raise_backtrace

Interface contract:

MACH_EXC_SERVER_TASKIDTOKEN

Mechanism: Sends an EXC_CORPSE_NOTIFY message containing a kcdata/backtrace-object port to eligible live exception endpoints. The sender tries its candidate ports and stops on success or receive-port death. The local Unix receiver returns invalid argument; interpretation of the diagnostic object by another receiver is outside that body. Local path.

Declarations: mach_exception_raise_backtrace (server64, server32, sender64, local64). Reserved instead in: client64, client32, libsyscall64.

Fields after preprocessing (server64):

routine mach_exception_raise_backtrace(
   exception_port : mach_port_t;
   kcdata_object_t : mach_port_t;
   exception : exception_type_t;
   code : mach_exception_data_t
   );

Local body: catch_mach_exception_raise_backtrace.

Implementation excerpt:

catch_mach_exception_raise_backtrace(
	__unused mach_port_t               exception_port,
	__unused mach_port_t               kcdata_object,
	__unused exception_type_t          exception,
	__unused mach_exception_data_t     code,
	__unused mach_msg_type_number_t    codeCnt)
{
	return KERN_INVALID_ARGUMENT;
}

2410: mach_exception_raise_state_identity_protected

Interface contract:

Same as identity_protected above, but also handles an in/out thread_state_t.

Mechanism: Combines a task identity token and thread ID with exported architecture state. Pointer-authentication policy affects state-export/import flags; a successful reply goes through thread_setstatus_from_user unless it is corpse notification. The local Unix receiver is an invalid-argument stub, so the implemented sender and a capable external receiver are distinct. Local path.

Declarations: mach_exception_raise_state_identity_protected (server64, server32, sender64, local64). Reserved instead in: client64, client32, libsyscall64.

Fields after preprocessing (server64):

routine mach_exception_raise_state_identity_protected(
   exception_port : mach_port_t;
   thread_id : uint64_t;
   task_id_token_t : mach_port_t;
   exception : exception_type_t;
   code : mach_exception_data_t;
   inout flavor : int;
   old_state : thread_state_t;
      out new_state : thread_state_t
   );

Local body: catch_mach_exception_raise_state_identity_protected.

Implementation excerpt:

catch_mach_exception_raise_state_identity_protected(
	__unused mach_port_t               exception_port,
	__unused uint64_t                  thread_id,
	__unused mach_port_t               task_id_token,
	__unused exception_type_t          exception,
	__unused mach_exception_data_t     code,
	__unused mach_msg_type_number_t    codeCnt,
	__unused int                      *flavor,
	__unused thread_state_t            old_state,
	__unused mach_msg_type_number_t    old_stateCnt,
	__unused thread_state_t            new_state,
	__unused mach_msg_type_number_t   *new_stateCnt)
{
	return KERN_INVALID_ARGUMENT;
}