Kernel Debug Protocol (KDP)

boolean_t
kdp_packet(
	unsigned char       *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	static unsigned     aligned_pkt[1538 / sizeof(unsigned) + 1];// max ether pkt
	kdp_pkt_t           *rd = (kdp_pkt_t *)&aligned_pkt;
	size_t              plen = *len;
	kdp_req_t           req;
	boolean_t           ret;

#if DO_ALIGN
	if (plen > sizeof(aligned_pkt)) {
		printf("kdp_packet bad len %lu\n", plen);
		return FALSE;
	}
	bcopy((char *)pkt, (char *)rd, plen);
#else
	rd = (kdp_pkt_t *)pkt;
#endif
	if (plen < sizeof(rd->hdr) || rd->hdr.len != plen) {
		printf("kdp_packet bad len pkt %lu hdr %d\n", plen, rd->hdr.len);

		return FALSE;
	}

	if (rd->hdr.is_reply) {
		printf("kdp_packet reply recvd req %x seq %x\n",
… more in source

static boolean_t
kdp_unknown(
	kdp_pkt_t           *pkt,
	__unused int        *len,
	__unused unsigned short     *reply_port
	)
{
	kdp_pkt_t           *rd = (kdp_pkt_t *)pkt;

	printf("kdp_unknown request %x len %d seq %x key %x\n",
	    rd->hdr.request, rd->hdr.len, rd->hdr.seq, rd->hdr.key);

	return FALSE;
}

static boolean_t
kdp_connect(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_connect_req_t   *rq = &pkt->connect_req;
	size_t              plen = *len;
	kdp_connect_reply_t *rp = &pkt->connect_reply;
	uint16_t            rport, eport;
	uint32_t            key;
	uint8_t             seq;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	dprintf(("kdp_connect seq %x greeting %s\n", rq->hdr.seq, rq->greeting));

	rport = rq->req_reply_port;
	eport = rq->exc_note_port;
	key   = rq->hdr.key;
	seq   = rq->hdr.seq;
	if (kdp.is_conn) {
		if ((seq == kdp.conn_seq) && /* duplicate request */
		    (rport == kdp.reply_port) &&
		    (eport == kdp.exception_port) &&
		    (key == kdp.session_key)) {
			rp->error = KDPERR_NO_ERROR;
… more in source

static boolean_t
kdp_disconnect(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_disconnect_req_t        *rq = &pkt->disconnect_req;
	size_t                      plen = *len;
	kdp_disconnect_reply_t      *rp = &pkt->disconnect_reply;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	if (!kdp.is_conn) {
		return FALSE;
	}

	dprintf(("kdp_disconnect\n"));

	*reply_port = kdp.reply_port;

	kdp.reply_port = kdp.exception_port = 0;
	kdp.is_halted = kdp.is_conn = FALSE;
	kdp.exception_seq = kdp.conn_seq = 0;
	kdp.session_key = 0;

	if (debugger_panic_str != NULL) {
		reattach_wait = 1;
… more in source

static boolean_t
kdp_reattach(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_reattach_req_t            *rq = &pkt->reattach_req;

	kdp.is_conn = TRUE;
	kdp_disconnect(pkt, len, reply_port);
	*reply_port = rq->req_reply_port;
	reattach_wait = 1;
	return TRUE;
}

static boolean_t
kdp_hostinfo(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_hostinfo_req_t  *rq = &pkt->hostinfo_req;
	size_t              plen = *len;
	kdp_hostinfo_reply_t *rp = &pkt->hostinfo_reply;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	dprintf(("kdp_hostinfo\n"));

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	kdp_machine_hostinfo(&rp->hostinfo);

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

static boolean_t
kdp_kernelversion(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_kernelversion_req_t     *rq = &pkt->kernelversion_req;
	size_t              plen = *len;
	kdp_kernelversion_reply_t *rp = &pkt->kernelversion_reply;
	size_t          slen;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	dprintf(("kdp_kernelversion\n"));
	slen = strlcpy(rp->version, kdp_kernelversion_string, MAX_KDP_DATA_SIZE);

	rp->hdr.len += slen + 1; /* strlcpy returns the amount copied with NUL */

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

static boolean_t
kdp_suspend(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_suspend_req_t   *rq = &pkt->suspend_req;
	size_t              plen = *len;
	kdp_suspend_reply_t *rp = &pkt->suspend_reply;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	dprintf(("kdp_suspend\n"));

	kdp.is_halted = TRUE;

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

static boolean_t
kdp_resumecpus(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_resumecpus_req_t        *rq = &pkt->resumecpus_req;
	size_t                      plen = *len;
	kdp_resumecpus_reply_t      *rp = &pkt->resumecpus_reply;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	dprintf(("kdp_resumecpus %x\n", rq->cpu_mask));

	kdp.is_halted = FALSE;

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

static boolean_t
kdp_writemem(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_writemem_req_t  *rq = &pkt->writemem_req;
	size_t              plen = *len;
	kdp_writemem_reply_t *rp = &pkt->writemem_reply;
	mach_vm_size_t      cnt;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	if (rq->nbytes > MAX_KDP_DATA_SIZE) {
		rp->error = KDPERR_BAD_NBYTES;
	} else {
		dprintf(("kdp_writemem addr %x size %d\n", rq->address, rq->nbytes));
		cnt = kdp_machine_vm_write((caddr_t)rq->data, (mach_vm_address_t)rq->address, rq->nbytes);
		rp->error = KDPERR_ACCESS(rq->nbytes, cnt);
		dprintf(("  cnt %lld error %d\n", cnt, rp->error));
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;
… more in source

static boolean_t
kdp_writemem64(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_writemem64_req_t        *rq = &pkt->writemem64_req;
	size_t              plen = *len;
	kdp_writemem64_reply_t *rp = &pkt->writemem64_reply;
	mach_vm_size_t              cnt;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	if (rq->nbytes > MAX_KDP_DATA_SIZE) {
		rp->error = KDPERR_BAD_NBYTES;
	} else {
		dprintf(("kdp_writemem64 addr %llx size %d\n", rq->address, rq->nbytes));
		cnt = kdp_machine_vm_write((caddr_t)rq->data, (mach_vm_address_t)rq->address, (mach_vm_size_t)rq->nbytes);
		rp->error = KDPERR_ACCESS(rq->nbytes, cnt);
		dprintf(("  cnt %lld error %d\n", cnt, rp->error));
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;
… more in source

static boolean_t
kdp_writephysmem64(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_writephysmem64_req_t    *rq = &pkt->writephysmem64_req;
	size_t              plen = *len;
	kdp_writephysmem64_reply_t *rp = &pkt->writephysmem64_reply;
	mach_vm_size_t              cnt;
	unsigned int                size;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	size = rq->nbytes;
	if (size > MAX_KDP_DATA_SIZE) {
		rp->error = KDPERR_BAD_NBYTES;
	} else {
		dprintf(("kdp_writephysmem64 addr %llx size %d\n", rq->address, size));
		cnt = kdp_machine_phys_write(rq, rq->data, rq->lcpu);
		rp->error = KDPERR_ACCESS(size, cnt);
		dprintf(("  cnt %lld error %d\n", cnt, rp->error));
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);
… more in source

static boolean_t
kdp_readmem(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_readmem_req_t   *rq = &pkt->readmem_req;
	size_t              plen = *len;
	kdp_readmem_reply_t *rp = &pkt->readmem_reply;
	mach_vm_size_t      cnt;
	unsigned int        size;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	size = rq->nbytes;
	if (size > MAX_KDP_DATA_SIZE) {
		rp->error = KDPERR_BAD_NBYTES;
	} else {
		dprintf(("kdp_readmem addr %x size %d\n", rq->address, size));
		cnt = kdp_machine_vm_read((mach_vm_address_t)rq->address, (caddr_t)rp->data, rq->nbytes);
		rp->error = KDPERR_ACCESS(size, cnt);
		dprintf(("  cnt %lld error %d\n", cnt, rp->error));

		rp->hdr.len += cnt;
… more in source

static boolean_t
kdp_readmem64(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_readmem64_req_t *rq = &pkt->readmem64_req;
	size_t              plen = *len;
	kdp_readmem64_reply_t *rp = &pkt->readmem64_reply;
	mach_vm_size_t      cnt;
	unsigned int        size;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	size = rq->nbytes;
	if (size > MAX_KDP_DATA_SIZE) {
		rp->error = KDPERR_BAD_NBYTES;
	} else {
		dprintf(("kdp_readmem64 addr %llx size %d\n", rq->address, size));
		cnt = kdp_machine_vm_read((mach_vm_address_t)rq->address, (caddr_t)rp->data, rq->nbytes);
		rp->error = KDPERR_ACCESS(size, cnt);
		dprintf(("  cnt %lld error %d\n", cnt, rp->error));

		rp->hdr.len += cnt;
… more in source

static boolean_t
kdp_readphysmem64(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_readphysmem64_req_t     *rq = &pkt->readphysmem64_req;
	size_t              plen = *len;
	kdp_readphysmem64_reply_t *rp = &pkt->readphysmem64_reply;
	mach_vm_size_t      cnt;
	unsigned int        size;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	size = rq->nbytes;
	if (size > MAX_KDP_DATA_SIZE) {
		rp->error = KDPERR_BAD_NBYTES;
	} else {
		dprintf(("kdp_readphysmem64 addr %llx size %d\n", rq->address, size));
		cnt = kdp_machine_phys_read(rq, rp->data, rq->lcpu);
		rp->error = KDPERR_ACCESS(size, cnt);
		dprintf(("  cnt %lld error %d\n", cnt, rp->error));

		rp->hdr.len += cnt;
… more in source

static boolean_t
kdp_maxbytes(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_maxbytes_req_t  *rq = &pkt->maxbytes_req;
	size_t              plen = *len;
	kdp_maxbytes_reply_t *rp = &pkt->maxbytes_reply;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	dprintf(("kdp_maxbytes\n"));

	rp->max_bytes = MAX_KDP_DATA_SIZE;

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

static boolean_t
kdp_version(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_version_req_t   *rq = &pkt->version_req;
	size_t              plen = *len;
	kdp_version_reply_t *rp = &pkt->version_reply;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	dprintf(("kdp_version\n"));

	rp->version = KDP_VERSION;
	if (!(kdp_flag & KDP_BP_DIS)) {
		rp->feature = KDP_FEATURE_BP;
	} else {
		rp->feature = 0;
	}

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;
… more in source

static boolean_t
kdp_regions(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_regions_req_t   *rq = &pkt->regions_req;
	size_t              plen = *len;
	kdp_regions_reply_t *rp = &pkt->regions_reply;
	kdp_region_t        *r;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	dprintf(("kdp_regions\n"));

	r = rp->regions;
	rp->nregions = 0;

	r->address = 0;
	r->nbytes = 0xffffffff;

	r->protection = VM_PROT_ALL; r++; rp->nregions++;

	rp->hdr.len += rp->nregions * sizeof(kdp_region_t);
… more in source

static boolean_t
kdp_writeregs(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_writeregs_req_t *rq = &pkt->writeregs_req;
	size_t              plen = *len;
	int                 size;
	kdp_writeregs_reply_t *rp = &pkt->writeregs_reply;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	size = rq->hdr.len - (unsigned)sizeof(kdp_hdr_t) - (unsigned)sizeof(unsigned int);
	rp->error = kdp_machine_write_regs(rq->cpu, rq->flavor, rq->data, &size);

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

static boolean_t
kdp_readregs(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_readregs_req_t  *rq = &pkt->readregs_req;
	size_t              plen = *len;
	kdp_readregs_reply_t *rp = &pkt->readregs_reply;
	int                 size;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	rp->error = kdp_machine_read_regs(rq->cpu, rq->flavor, rp->data, &size);
	rp->hdr.len += size;

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

boolean_t
kdp_breakpoint_set(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_breakpoint_req_t    *rq = &pkt->breakpoint_req;
	kdp_breakpoint_reply_t *rp = &pkt->breakpoint_reply;
	size_t          plen = *len;
	kdp_error_t     kerr;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	dprintf(("kdp_breakpoint_set %x\n", rq->address));

	kerr = kdp_set_breakpoint_internal((mach_vm_address_t)rq->address);

	rp->error = kerr;

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);
	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

boolean_t
kdp_breakpoint64_set(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_breakpoint64_req_t  *rq = &pkt->breakpoint64_req;
	kdp_breakpoint64_reply_t *rp = &pkt->breakpoint64_reply;
	size_t          plen = *len;
	kdp_error_t     kerr;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	dprintf(("kdp_breakpoint64_set %llx\n", rq->address));

	kerr = kdp_set_breakpoint_internal((mach_vm_address_t)rq->address);

	rp->error = kerr;

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);
	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

boolean_t
kdp_breakpoint_remove(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_breakpoint_req_t    *rq = &pkt->breakpoint_req;
	kdp_breakpoint_reply_t *rp = &pkt->breakpoint_reply;
	size_t          plen = *len;
	kdp_error_t     kerr;
	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	dprintf(("kdp_breakpoint_remove %x\n", rq->address));

	kerr = kdp_remove_breakpoint_internal((mach_vm_address_t)rq->address);

	rp->error = kerr;

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);
	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

boolean_t
kdp_breakpoint64_remove(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_breakpoint64_req_t  *rq = &pkt->breakpoint64_req;
	kdp_breakpoint64_reply_t *rp = &pkt->breakpoint64_reply;
	size_t          plen = *len;
	kdp_error_t     kerr;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	dprintf(("kdp_breakpoint64_remove %llx\n", rq->address));

	kerr = kdp_remove_breakpoint_internal((mach_vm_address_t)rq->address);

	rp->error = kerr;

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);
	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

kdp_error_t
kdp_set_breakpoint_internal(
	mach_vm_address_t   address
	)
{
	uint8_t         breakinstr[MAX_BREAKINSN_BYTES], oldinstr[MAX_BREAKINSN_BYTES];
	uint32_t        breakinstrsize = sizeof(breakinstr);
	mach_vm_size_t  cnt;
	int                     i;

	kdp_machine_get_breakinsn(breakinstr, &breakinstrsize);

	if (breakpoints_initialized == 0) {
		for (i = 0; (i < MAX_BREAKPOINTS); breakpoint_list[i].address = 0, i++) {
			;
		}
		breakpoints_initialized++;
	}

	cnt = kdp_machine_vm_read(address, (caddr_t)&oldinstr, (mach_vm_size_t)breakinstrsize);

	if (0 == memcmp(oldinstr, breakinstr, breakinstrsize)) {
		printf("A trap was already set at that address, not setting new breakpoint\n");

		return KDPERR_BREAKPOINT_ALREADY_SET;
	}

	for (i = 0; (i < MAX_BREAKPOINTS) && (breakpoint_list[i].address != 0); i++) {
		;
	}
… more in source

kdp_error_t
kdp_remove_breakpoint_internal(
	mach_vm_address_t   address
	)
{
	mach_vm_size_t  cnt;
	int             i;

	for (i = 0; (i < MAX_BREAKPOINTS) && (breakpoint_list[i].address != address); i++) {
		;
	}

	if (i == MAX_BREAKPOINTS) {
		return KDPERR_BREAKPOINT_NOT_FOUND;
	}

	breakpoint_list[i].address = 0;
	cnt = kdp_machine_vm_write((caddr_t)&breakpoint_list[i].oldbytes, address, breakpoint_list[i].bytesused);

	return KDPERR_NO_ERROR;
}

boolean_t
kdp_remove_all_breakpoints(void)
{
	int i;
	boolean_t breakpoint_found = FALSE;

	if (breakpoints_initialized) {
		for (i = 0; i < MAX_BREAKPOINTS; i++) {
			if (breakpoint_list[i].address) {
				kdp_machine_vm_write((caddr_t)&(breakpoint_list[i].oldbytes), (mach_vm_address_t)breakpoint_list[i].address, (mach_vm_size_t)breakpoint_list[i].bytesused);
				breakpoint_found = TRUE;
				breakpoint_list[i].address = 0;
			}
		}

		if (breakpoint_found) {
			printf("kdp_remove_all_breakpoints: found extant breakpoints, removing them.\n");
		}
	}
	return breakpoint_found;
}

boolean_t
kdp_reboot(
	__unused kdp_pkt_t *pkt,
	__unused int    *len,
	__unused unsigned short *reply_port
	)
{
	dprintf(("kdp_reboot\n"));

	kdp_machine_reboot();

	return TRUE; // no, not really, we won't return
}

static boolean_t
kdp_readioport(
	kdp_pkt_t           *pkt,
	int                 *len,
	unsigned short      *reply_port
	)
{
	kdp_readioport_req_t   *rq = &pkt->readioport_req;
	kdp_readioport_reply_t *rp = &pkt->readioport_reply;
	size_t plen = *len;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	if (rq->nbytes > MAX_KDP_DATA_SIZE) {
		rp->error = KDPERR_BAD_NBYTES;
	} else {
#if KDP_TEST_HARNESS
		uint16_t addr = rq->address;
#endif
		uint16_t size = rq->nbytes;
		dprintf(("kdp_readioport addr %x size %d\n", addr, size));

		rp->error = kdp_machine_ioport_read(rq, rp->data, rq->lcpu);
		if (rp->error == KDPERR_NO_ERROR) {
			rp->hdr.len += size;
… more in source

static boolean_t
kdp_writeioport(
	kdp_pkt_t       *pkt,
	int             *len,
	unsigned short  *reply_port
	)
{
	kdp_writeioport_req_t   *rq = &pkt->writeioport_req;
	kdp_writeioport_reply_t *rp = &pkt->writeioport_reply;
	size_t  plen = *len;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	if (rq->nbytes > MAX_KDP_DATA_SIZE) {
		rp->error = KDPERR_BAD_NBYTES;
	} else {
		dprintf(("kdp_writeioport addr %x size %d\n", rq->address,
		    rq->nbytes));

		rp->error = kdp_machine_ioport_write(rq, rq->data, rq->lcpu);
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;
… more in source

static boolean_t
kdp_readmsr64(
	kdp_pkt_t               *pkt,
	int                     *len,
	unsigned short  *reply_port
	)
{
	kdp_readmsr64_req_t   *rq = &pkt->readmsr64_req;
	kdp_readmsr64_reply_t *rp = &pkt->readmsr64_reply;
	size_t plen = *len;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	dprintf(("kdp_readmsr64 lcpu %x addr %x\n", rq->lcpu, rq->address));
	rp->error = kdp_machine_msr64_read(rq, rp->data, rq->lcpu);
	if (rp->error == KDPERR_NO_ERROR) {
		rp->hdr.len += sizeof(uint64_t);
	}

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

static boolean_t
kdp_writemsr64(
	kdp_pkt_t       *pkt,
	int             *len,
	unsigned short  *reply_port
	)
{
	kdp_writemsr64_req_t   *rq = &pkt->writemsr64_req;
	kdp_writemsr64_reply_t *rp = &pkt->writemsr64_reply;
	size_t  plen = *len;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	dprintf(("kdp_writemsr64 lcpu %x addr %x\n", rq->lcpu, rq->address));
	rp->error = kdp_machine_msr64_write(rq, rq->data, rq->lcpu);

	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;

	return TRUE;
}

static boolean_t
kdp_dumpinfo(
	kdp_pkt_t       *pkt,
	int             *len,
	unsigned short  *reply_port
	)
{
	kdp_dumpinfo_req_t   *rq = &pkt->dumpinfo_req;
	kdp_dumpinfo_reply_t *rp = &pkt->dumpinfo_reply;
	size_t  plen = *len;

	if (plen < sizeof(*rq)) {
		return FALSE;
	}

	dprintf(("kdp_dumpinfo file=%s destip=%s routerip=%s\n", rq->name, rq->destip, rq->routerip));
	rp->hdr.is_reply = 1;
	rp->hdr.len = sizeof(*rp);

	if ((rq->type & KDP_DUMPINFO_MASK) != KDP_DUMPINFO_GETINFO) {
		kdp_set_dump_info(rq->type, rq->name, rq->destip, rq->routerip,
		    rq->port);
	}

	/* gather some stats for reply */
	kdp_get_dump_info(rp);

	*reply_port = kdp.reply_port;
	*len = rp->hdr.len;
… more in source

typedef struct{ mach_vm_address_t address; uint32_t bytesused; uint8_t oldbytes[MAX_BREAKINSN_BYTES]; } kdp_breakpoint_record_t;