This is xnu-12377.1.9. See this file in:
#include <stdlib.h>
#include <stdio.h>
#include <pthread.h>
#include <pthread/private.h>
#include <unistd.h>
#include <mach/kern_return.h>
#include <mach/mach.h>
#include <mach/task.h>
#include <mach/thread_status.h>
#include <os/tsd.h>
#include <assert.h>
#include <sys/codesign.h>
#include <stdbool.h>
#include <darwintest.h>
#include <mach/mk_timer.h>
#include "cs_helpers.h"
#define MAX_TEST_NUM 22
#if __arm64__
#define machine_thread_state_t arm_thread_state64_t
#define EXCEPTION_THREAD_STATE ARM_THREAD_STATE64
#define EXCEPTION_THREAD_STATE_COUNT ARM_THREAD_STATE64_COUNT
#elif __x86_64__
#define machine_thread_state_t x86_thread_state_t
#define EXCEPTION_THREAD_STATE x86_THREAD_STATE
#define EXCEPTION_THREAD_STATE_COUNT x86_THREAD_STATE_COUNT
#else
#error Unsupported architecture
#endif
/* in xpc/launch_private.h */
#define XPC_DOMAIN_SYSTEM 1
static mach_port_t
alloc_server_port(void)
{
mach_port_t server_port = MACH_PORT_NULL;
kern_return_t kr;
kr = mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &server_port);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "alloc_server_port");
kr = mach_port_insert_right(mach_task_self(), server_port, server_port, MACH_MSG_TYPE_MAKE_SEND);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "alloc_server_port mach_port_insert_right");
return server_port;
}
static mach_port_t
alloc_reply_port()
{
kern_return_t kr;
mach_port_t reply_port = MACH_PORT_NULL;
mach_port_options_t opts = {
.flags = MPO_REPLY_PORT | MPO_INSERT_SEND_RIGHT,
};
kr = mach_port_construct(mach_task_self(), &opts, 0, &reply_port);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "alloc_reply_port");
T_QUIET; T_ASSERT_NE(reply_port, (mach_port_t)MACH_PORT_NULL, "reply_port_create: %s", mach_error_string(kr));
return reply_port;
}
static mach_port_t
alloc_weak_reply_port()
{
kern_return_t kr;
mach_port_t reply_port = MACH_PORT_NULL;
mach_port_options_t opts = {
.flags = MPO_PROVISIONAL_REPLY_PORT,
};
kr = mach_port_construct(mach_task_self(), &opts, 0, &reply_port);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "alloc_reply_port");
T_QUIET; T_ASSERT_NE(reply_port, (mach_port_t)MACH_PORT_NULL, "weak_reply_port_create: %s", mach_error_string(kr));
return reply_port;
}
static mach_port_t
alloc_service_port(void)
{
kern_return_t kr;
mach_port_t service_port = MACH_PORT_NULL;
struct mach_service_port_info sp_info = {
.mspi_string_name = "com.apple.testservice",
.mspi_domain_type = XPC_DOMAIN_SYSTEM,
};
mach_port_options_t opts = {
.flags = MPO_STRICT_SERVICE_PORT | MPO_INSERT_SEND_RIGHT,
.service_port_info = &sp_info,
};
kr = mach_port_construct(mach_task_self(), &opts, 0, &service_port);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "alloc_service_port");
return service_port;
}
static mach_port_t
alloc_weak_service_port(void)
{
kern_return_t kr;
mach_port_t weak_service_port = MACH_PORT_NULL;
struct mach_service_port_info sp_info = {
.mspi_string_name = "com.apple.testservice",
.mspi_domain_type = XPC_DOMAIN_SYSTEM,
};
mach_port_options_t opts = {
.flags = MPO_SERVICE_PORT | MPO_INSERT_SEND_RIGHT,
.service_port_info = &sp_info,
};
kr = mach_port_construct(mach_task_self(), &opts, 0, &weak_service_port);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "alloc_weak_service_port");
return weak_service_port;
}
/* The rcv right of the port would be marked immovable. */
static void
test_immovable_receive_right(void)
{
kern_return_t kr;
mach_port_t server_port = MACH_PORT_NULL, reply_port = MACH_PORT_NULL;
struct {
mach_msg_header_t header;
mach_msg_body_t body;
mach_msg_port_descriptor_t desc;
} msg;
server_port = alloc_server_port();
reply_port = alloc_reply_port();
msg.header.msgh_remote_port = server_port;
msg.header.msgh_local_port = MACH_PORT_NULL;
msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0) | MACH_MSGH_BITS_COMPLEX;
msg.header.msgh_size = sizeof msg;
msg.body.msgh_descriptor_count = 1;
msg.desc.name = reply_port;
msg.desc.disposition = MACH_MSG_TYPE_MOVE_RECEIVE;
msg.desc.type = MACH_MSG_PORT_DESCRIPTOR;
kr = mach_msg_send(&msg.header);
printf("[reply_port_defense_client test_immovable_receive_right]: mach_msg2() returned %d\n", kr);
}
/* The only way you could create a send once right is when you send the port in local port of a mach msg with MAKE_SEND_ONCE disposition. */
static void
test_make_send_once_right(void)
{
kern_return_t kr;
mach_port_t reply_port = alloc_reply_port();
kr = mach_port_insert_right(mach_task_self(), reply_port, reply_port, MACH_MSG_TYPE_MAKE_SEND_ONCE);
printf("[reply_port_defense_client test_make_send_once_right]: mach_port_insert_right() returned %d\n", kr);
}
static void
test_alloc_weak_reply_port(void)
{
mach_port_t reply_port = alloc_weak_reply_port();
printf("[reply_port_defense_client test_alloc_weak_reply_port]: did not crash with port=%d\n", reply_port);
}
/* The send right of the port would only used for guarding a name in ipc space, it would not allow to send a message. */
static void
test_using_send_right(void)
{
kern_return_t kr;
mach_port_t reply_port = alloc_reply_port();
struct {
mach_msg_header_t header;
mach_msg_body_t body;
} msg;
msg.header.msgh_remote_port = reply_port;
msg.header.msgh_local_port = MACH_PORT_NULL;
msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0);
msg.header.msgh_size = sizeof msg;
kr = mach_msg_send(&msg.header);
printf("[reply_port_defense_client test_using_send_right]: mach_msg2() returned %d\n", kr);
}
/* The send right of the port would only used for guarding a name in ipc space, it would not allowed to get moved. */
static void
test_move_send_right(void)
{
kern_return_t kr;
mach_port_t server_port = MACH_PORT_NULL, reply_port = MACH_PORT_NULL;
struct {
mach_msg_header_t header;
mach_msg_body_t body;
mach_msg_port_descriptor_t desc;
} msg;
server_port = alloc_server_port();
reply_port = alloc_reply_port();
msg.header.msgh_remote_port = server_port;
msg.header.msgh_local_port = MACH_PORT_NULL;
msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0) | MACH_MSGH_BITS_COMPLEX;
msg.header.msgh_size = sizeof msg;
msg.body.msgh_descriptor_count = 1;
msg.desc.name = reply_port;
msg.desc.disposition = MACH_MSG_TYPE_MOVE_SEND;
msg.desc.type = MACH_MSG_PORT_DESCRIPTOR;
kr = mach_msg_send(&msg.header);
printf("[reply_port_defense_client test_move_send_right]: mach_msg2() returned %d\n", kr);
}
static void
test_unentitled_thread_set_state(void)
{
machine_thread_state_t ts;
mach_msg_type_number_t count = MACHINE_THREAD_STATE_COUNT;
/* thread_set_state as a platform restrictions binary should fail */
kern_return_t kr = thread_get_state(mach_thread_self(), MACHINE_THREAD_STATE, (thread_state_t)&ts, &count);
kr = thread_set_state(mach_thread_self(), MACHINE_THREAD_STATE, (thread_state_t)&ts, count);
assert(kr != KERN_SUCCESS);
exit(-1); /* Should have crashed before here! */
}
static void
test_unentitled_thread_set_exception_ports(void)
{
mach_port_t exc_port = alloc_server_port();
/* thread_set_exception_ports as a platform restrictions binary should fail without identity protected options */
kern_return_t kr = thread_set_exception_ports(
mach_thread_self(),
EXC_MASK_ALL,
exc_port,
(exception_behavior_t)((unsigned int)EXCEPTION_DEFAULT | MACH_EXCEPTION_CODES),
EXCEPTION_THREAD_STATE);
/* thread_set_exception_ports is supposed to crash, unless the policy is turned off.
* Things that disable the policy: AMFI boot-args in use, SIP disabled,
* third party plugins in a process. The caller of this client will check
* whether the test crashed and correctly adhered to these policies.
*/
printf("thread_set_exception_ports did not crash\n");
}
static void
unentitled_set_exception_ports_pass(void)
{
mach_port_t exc_port = alloc_server_port();
/* thread_set_exception_ports with state *IDENTITY_PROTECTED should not fail */
kern_return_t kr = thread_set_exception_ports(
mach_thread_self(),
EXC_MASK_ALL,
exc_port,
(exception_behavior_t)((unsigned int)EXCEPTION_STATE_IDENTITY_PROTECTED | MACH_EXCEPTION_CODES),
EXCEPTION_THREAD_STATE);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "thread_set_exception_ports EXCEPTION_STATE_IDENTITY_PROTECTED");
kr = thread_set_exception_ports(
mach_thread_self(),
EXC_MASK_ALL,
exc_port,
(exception_behavior_t)((unsigned int)EXCEPTION_IDENTITY_PROTECTED | MACH_EXCEPTION_CODES),
EXCEPTION_THREAD_STATE);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "thread_set_exception_ports EXCEPTION_IDENTITY_PROTECTED");
return;
}
static void
exception_ports_crash(void)
{
kern_return_t kr;
mach_port_t exc_port;
mach_port_options_t opts = {
.flags = MPO_INSERT_SEND_RIGHT | MPO_EXCEPTION_PORT,
};
kr = mach_port_construct(mach_task_self(), &opts, 0ull, &exc_port);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "exception_ports_crash mach_port_construct");
kr = task_register_hardened_exception_handler(current_task(),
0, EXC_MASK_BAD_ACCESS,
EXCEPTION_STATE_IDENTITY_PROTECTED, EXCEPTION_THREAD_STATE, exc_port);
kr = thread_set_exception_ports(
mach_thread_self(),
EXC_MASK_BAD_ACCESS,
exc_port,
(exception_behavior_t)((unsigned int)EXCEPTION_STATE_IDENTITY_PROTECTED | MACH_EXCEPTION_CODES),
EXCEPTION_THREAD_STATE);
printf("thread_set_exception_ports did not crash: %d\n", kr);
}
static void
kobject_reply_port_defense(void)
{
machine_thread_state_t ts;
mach_msg_type_number_t count = MACHINE_THREAD_STATE_COUNT;
mach_port_t port = MACH_PORT_NULL;
kern_return_t kr = mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &port);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "kobject_reply_port_defense mach_port_allocate");
// make a kobject call
kr = thread_get_state(mach_thread_self(), MACHINE_THREAD_STATE, (thread_state_t)&ts, &count);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "kobject_reply_port_defense thread_get_state");
// set the MIG reply port to a "normal" port
_os_tsd_set_direct(__TSD_MIG_REPLY, (void *)(uintptr_t)port);
kr = thread_get_state(mach_thread_self(), MACHINE_THREAD_STATE, (thread_state_t)&ts, &count);
T_FAIL("kobject call did not crash: %d\n", kr);
}
static void
test_move_service_port(void)
{
kern_return_t kr;
mach_port_t server_port = MACH_PORT_NULL, service_port = MACH_PORT_NULL;
struct {
mach_msg_header_t header;
mach_msg_body_t body;
mach_msg_port_descriptor_t desc;
} msg;
server_port = alloc_server_port();
service_port = alloc_service_port();
msg.header.msgh_remote_port = server_port;
msg.header.msgh_local_port = MACH_PORT_NULL;
msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0) | MACH_MSGH_BITS_COMPLEX;
msg.header.msgh_size = sizeof msg;
msg.body.msgh_descriptor_count = 1;
msg.desc.name = service_port;
msg.desc.disposition = MACH_MSG_TYPE_MOVE_RECEIVE;
msg.desc.type = MACH_MSG_PORT_DESCRIPTOR;
kr = mach_msg_send(&msg.header);
T_FAIL("move service port did not crash: %d\n", kr);
}
static void
test_mktimer_notification_policy(void)
{
mach_port_t timer_port = MACH_PORT_NULL;
mach_port_t notify_port = MACH_PORT_NULL;
mach_port_t previous = MACH_PORT_NULL;
kern_return_t kr = KERN_SUCCESS;
timer_port = mk_timer_create();
T_ASSERT_NE(timer_port, (mach_port_t)MACH_PORT_NULL, "mk_timer_create: %s", mach_error_string(kr));
/* notification port for the mk_timer port to come back on */
kr = mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, ¬ify_port);
T_ASSERT_EQ(kr, KERN_SUCCESS, "mach_port_allocate(notify_port): %s", mach_error_string(kr));
T_LOG("timer: 0x%x, notify: 0x%x", timer_port, notify_port);
/* request a port-destroyed notification on the timer port, which should crash */
kr = mach_port_request_notification(mach_task_self(), timer_port, MACH_NOTIFY_PORT_DESTROYED,
0, notify_port, MACH_MSG_TYPE_MAKE_SEND_ONCE, &previous);
T_FAIL("mktimer did not crash with exc_guard kr=%d", kr);
}
static void
test_reply_port_port_destroyed_notification_policy(void)
{
mach_port_t reply_port = MACH_PORT_NULL;
mach_port_t previous = MACH_PORT_NULL;
mach_port_t notify_port = MACH_PORT_NULL;
kern_return_t kr = KERN_SUCCESS;
mach_port_options_t opts = {};
reply_port = alloc_reply_port();
kr = mach_port_construct(mach_task_self(), &opts, 0, ¬ify_port);
T_ASSERT_EQ(kr, KERN_SUCCESS, "mach_port_allocate(notify_port): %s", mach_error_string(kr));
/* request a port-destroyed notification on the reply port */
kr = mach_port_request_notification(mach_task_self(), reply_port, MACH_NOTIFY_PORT_DESTROYED,
0, notify_port, MACH_MSG_TYPE_MAKE_SEND_ONCE, &previous);
printf("reply port did not crash kr=%d\n", kr);
}
static void
test_reply_port_no_senders_notification_policy(void)
{
mach_port_t reply_port = MACH_PORT_NULL;
mach_port_t previous = MACH_PORT_NULL;
mach_port_t notify_port = MACH_PORT_NULL;
kern_return_t kr = KERN_SUCCESS;
reply_port = alloc_reply_port();
mach_port_options_t opts = {};
kr = mach_port_construct(mach_task_self(), &opts, 0, ¬ify_port);
T_ASSERT_EQ(kr, KERN_SUCCESS, "mach_port_allocate(notify_port): %s", mach_error_string(kr));
/* request a no-senders notification on the reply port */
kr = mach_port_request_notification(mach_task_self(), reply_port, MACH_NOTIFY_NO_SENDERS,
0, notify_port, MACH_MSG_TYPE_MAKE_SEND_ONCE, &previous);
T_FAIL("reply port did not crash kr=%d", kr);
}
static void
test_reply_port_insert_right_disallowed(void)
{
mach_port_t reply_port = MACH_PORT_NULL;
mach_port_t send_reply_port = MACH_PORT_NULL;
mach_msg_type_name_t right = 0;
kern_return_t kr = KERN_SUCCESS;
reply_port = alloc_reply_port();
kr = mach_port_extract_right(mach_task_self(), reply_port, MACH_MSG_TYPE_MAKE_SEND_ONCE, &send_reply_port, &right);
T_ASSERT_EQ(kr, KERN_SUCCESS, "mach_port_extract_right(reply_port, make_send_once): %s", mach_error_string(kr));
T_FAIL("reply port make send once outside of kmsg did not crash kr=%d", kr);
}
static kern_return_t
move_port(mach_port_t immovable_port)
{
mach_port_t server_port = MACH_PORT_NULL;
struct {
mach_msg_header_t header;
mach_msg_body_t body;
mach_msg_port_descriptor_t desc;
} msg;
server_port = alloc_server_port();
msg.header.msgh_remote_port = server_port;
msg.header.msgh_local_port = MACH_PORT_NULL;
msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0) | MACH_MSGH_BITS_COMPLEX;
msg.header.msgh_size = sizeof msg;
msg.body.msgh_descriptor_count = 1;
msg.desc.name = immovable_port;
msg.desc.disposition = MACH_MSG_TYPE_MOVE_SEND;
msg.desc.type = MACH_MSG_PORT_DESCRIPTOR;
return mach_msg_send(&msg.header);
}
/* attempt to move mach_task_self */
static void
test_mach_task_self_send_movability(void)
{
kern_return_t kr = move_port(mach_task_self());
printf("[reply_port_defense_client test_task_self_immovable]: mach_msg2() returned %d\n", kr);
}
/* mach_task_self() is movable before and after calling task_get_special_port, when entitled */
static void
test_task_self_movable_send(void)
{
kern_return_t kr;
mach_port_t task_self = MACH_PORT_NULL;
kr = move_port(mach_task_self());
T_EXPECT_MACH_SUCCESS(kr, "move mach_task_self");
kr = task_get_special_port(mach_task_self(), TASK_KERNEL_PORT, &task_self);
T_EXPECT_MACH_SUCCESS(kr, "task_get_special_port");
kr = move_port(mach_task_self());
T_EXPECT_MACH_SUCCESS(kr, "move mach_task_self again");
mach_port_t thread_port = pthread_mach_thread_np(pthread_main_thread_np());
kr = move_port(thread_port);
T_EXPECT_MACH_SUCCESS(kr, "move main_thread_port");
}
static void
test_move_newly_constructed_port_immovable_send(void)
{
kern_return_t kr;
mach_port_t port = MACH_PORT_NULL;
mach_port_options_t opts = {
.flags = MPO_INSERT_SEND_RIGHT | MPO_CONNECTION_PORT,
.service_port_name = MPO_ANONYMOUS_SERVICE,
};
kr = mach_port_construct(mach_task_self(), &opts, 0, &port);
kr = move_port(port);
printf("kr=%d\n", kr);
T_EXPECT_MACH_ERROR(kr, KERN_DENIED, "move port with immovable send rights");
}
static void
test_move_special_reply_port(void)
{
kern_return_t kr;
mach_port_t special_reply_port = thread_get_special_reply_port();
kr = move_port(special_reply_port);
T_EXPECT_MACH_ERROR(kr, KERN_DENIED, "move special reply port");
}
static void
test_reply_port_header_disposition(void)
{
kern_return_t kr;
mach_port_t server_port = MACH_PORT_NULL;
mach_port_t reply_port1 = MACH_PORT_NULL, reply_port2 = MACH_PORT_NULL;
struct {
mach_msg_header_t header;
} msg;
server_port = alloc_server_port();
reply_port1 = alloc_reply_port();
reply_port2 = alloc_reply_port();
msg.header.msgh_remote_port = server_port;
msg.header.msgh_size = sizeof msg;
/* sending with make_send_once should succeed */
msg.header.msgh_local_port = reply_port1;
msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND,
MACH_MSG_TYPE_MAKE_SEND_ONCE);
kr = mach_msg_send(&msg.header);
T_EXPECT_MACH_SUCCESS(kr, "reply_port_disposition make_send_once");
/* sending with make_send should fail */
msg.header.msgh_local_port = reply_port2;
msg.header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND,
MACH_MSG_TYPE_MAKE_SEND);
kr = mach_msg_send(&msg.header);
T_ASSERT_MACH_ERROR(kr, MACH_SEND_INVALID_REPLY, "reply_port_disposition make_send");
}
static void
test_service_port_as_exception_port(void)
{
kern_return_t kr;
mach_port_t service_port = alloc_service_port();
mach_port_t weak_service_port = alloc_weak_service_port();
kr = thread_set_exception_ports(
mach_thread_self(),
EXC_MASK_ALL,
service_port,
(exception_behavior_t)((unsigned int)EXCEPTION_STATE_IDENTITY_PROTECTED | MACH_EXCEPTION_CODES),
EXCEPTION_THREAD_STATE);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "test_service_port_as_exception_port IOT_SERVICE_PORT");
kr = thread_set_exception_ports(
mach_thread_self(),
EXC_MASK_ALL,
weak_service_port,
(exception_behavior_t)((unsigned int)EXCEPTION_STATE_IDENTITY_PROTECTED | MACH_EXCEPTION_CODES),
EXCEPTION_THREAD_STATE);
T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "test_service_port_as_exception_port IOT_WEAK_SERVICE_PORT");
}
int
main(int argc, char *argv[])
{
uint32_t my_csflags = 0;
bool thirdparty_hardened = !strcmp(argv[0], "./reply_port_defense_client_3P_hardened");
T_ASSERT_POSIX_ZERO(csops(getpid(), CS_OPS_STATUS, &my_csflags, sizeof(my_csflags)), NULL);
/* TODO add some sysctl which disabled platform binary bit here */
if ((my_csflags & CS_PLATFORM_BINARY) == thirdparty_hardened) {
printf("platform binary does not match expected\n");
return -1;
}
void (*tests[MAX_TEST_NUM])(void) = {
test_immovable_receive_right, /* 0 */
test_using_send_right, /* 1 */
test_move_send_right, /* 2 */
test_make_send_once_right, /* 3 */
NULL, /* 4 */
test_unentitled_thread_set_exception_ports, /* 5 */
test_unentitled_thread_set_state, /* 6 */
unentitled_set_exception_ports_pass,
exception_ports_crash, /* 8 */
kobject_reply_port_defense, /* 9 */
test_alloc_weak_reply_port, /* 10 */
test_move_service_port, /* 11 */
test_mktimer_notification_policy, /* 12 */
test_reply_port_port_destroyed_notification_policy, /* 13 */
test_reply_port_no_senders_notification_policy, /* 14 */
test_reply_port_insert_right_disallowed, /* 15 */
test_mach_task_self_send_movability, /* 16 */
test_task_self_movable_send, /* 17 */
test_move_newly_constructed_port_immovable_send, /* 18 */
test_move_special_reply_port, /* 19 */
test_reply_port_header_disposition, /* 20 */
test_service_port_as_exception_port, /* 21 */
};
if (argc < 2) {
printf("[reply_port_defense_client]: Specify a test to run.");
exit(-1);
}
int test_num = atoi(argv[1]);
printf("[reply_port_defense_client]: My Pid: %d Test num: %d third_party_hardened: %s\n",
getpid(), test_num, thirdparty_hardened ? "yes" : "no");
fflush(stdout);
if (test_num >= 0 && test_num < MAX_TEST_NUM) {
(*tests[test_num])();
} else {
printf("[reply_port_defense_client]: Invalid test num. Exiting...\n");
exit(-1);
}
printf("Child exiting cleanly!!\n");
fflush(stdout);
// return 0;
exit(0);
}