ACPICA: New: I/O port protection

Protect certain I/O ports from reads/writes. Provides MS
compatibility. New module, hwvalid.c

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 240 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/hwvalid.c b/drivers/acpi/acpica/hwvalid.c
new file mode 100644
index 00000000000..e0b562fbe7c
--- /dev/null
+++ b/drivers/acpi/acpica/hwvalid.c
@@ -0,0 +1,240 @@
+
+/******************************************************************************
+ *
+ * Module Name: hwvalid - I/O request validation
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2009, Intel Corp.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ *    of any contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ */
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+
+#define _COMPONENT          ACPI_HARDWARE
+ACPI_MODULE_NAME("hwvalid")
+
+/* Local prototypes */
+static acpi_status
+acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width);
+
+/*
+ * Protected I/O ports. Some ports are always illegal, and some are
+ * conditionally illegal. This table must remain ordered by port address.
+ *
+ * The table is used to implement the Microsoft port access rules that
+ * first appeared in Windows XP. Some ports are always illegal, and some
+ * ports are only illegal if the BIOS calls _OSI with a win_xP string or
+ * later (meaning that the BIOS itelf is post-XP.)
+ *
+ * This provides ACPICA with the desired port protections and
+ * Microsoft compatibility.
+ */
+static const struct acpi_port_info acpi_protected_ports[] = {
+	{"DMA1", 0x0000, 0x000F, ACPI_OSI_WIN_XP},
+	{"PIC0", 0x0020, 0x0021, ACPI_ALWAYS_ILLEGAL},
+	{"PIT1", 0x0040, 0x0043, ACPI_OSI_WIN_XP},
+	{"PIT2", 0x0048, 0x004B, ACPI_OSI_WIN_XP},
+	{"RTC", 0x0070, 0x0071, ACPI_OSI_WIN_XP},
+	{"CMOS", 0x0074, 0x0076, ACPI_OSI_WIN_XP},
+	{"DMA1", 0x0081, 0x0083, ACPI_OSI_WIN_XP},
+	{"DMA1", 0x0087, 0x0087, ACPI_OSI_WIN_XP},
+	{"DMA2", 0x0089, 0x0089, ACPI_OSI_WIN_XP},
+	{"DMA2", 0x008A, 0x008B, ACPI_OSI_WIN_XP},
+	{"DMA2", 0x008F, 0x008F, ACPI_OSI_WIN_XP},
+	{"Arb", 0x0090, 0x0091, ACPI_OSI_WIN_XP},
+	{"Setup", 0x0093, 0x0094, ACPI_OSI_WIN_XP},
+	{"POS", 0x0096, 0x0097, ACPI_OSI_WIN_XP},
+	{"PIC1", 0x00A0, 0x00A1, ACPI_ALWAYS_ILLEGAL},
+	{"DMA", 0x00C0, 0x00DF, ACPI_OSI_WIN_XP},
+	{"ELCR", 0x04D0, 0x04D1, ACPI_ALWAYS_ILLEGAL},
+	{"PCI", 0x0CF8, 0x0D00, ACPI_OSI_WIN_XP}
+};
+
+#define ACPI_PORT_INFO_ENTRIES  ACPI_ARRAY_LENGTH (acpi_protected_ports)
+
+/******************************************************************************
+ *
+ * FUNCTION:    acpi_hw_validate_io_request
+ *
+ * PARAMETERS:  Address             Address of I/O port/register
+ *              bit_width           Number of bits (8,16,32)
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Validates an I/O request (address/length). Certain ports are
+ *              always illegal and some ports are only illegal depending on
+ *              the requests the BIOS AML code makes to the predefined
+ *              _OSI method.
+ *
+ ******************************************************************************/
+
+static acpi_status
+acpi_hw_validate_io_request(acpi_io_address address, u32 bit_width)
+{
+	u32 i;
+	u32 byte_width;
+	acpi_io_address last_address;
+	const struct acpi_port_info *port_info;
+
+	ACPI_FUNCTION_TRACE(hw_validate_io_request);
+
+	/* Supported widths are 8/16/32 */
+
+	if ((bit_width != 8) && (bit_width != 16) && (bit_width != 32)) {
+		return AE_BAD_PARAMETER;
+	}
+
+	port_info = acpi_protected_ports;
+	byte_width = ACPI_DIV_8(bit_width);
+	last_address = address + byte_width - 1;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_IO, "Address %p LastAddress %p Length %X",
+			  ACPI_CAST_PTR(void, address), ACPI_CAST_PTR(void,
+								      last_address),
+			  byte_width));
+
+	/* Maximum 16-bit address in I/O space */
+
+	if (last_address > ACPI_UINT16_MAX) {
+		ACPI_ERROR((AE_INFO,
+			    "Illegal I/O port address/length above 64K: 0x%p/%X",
+			    ACPI_CAST_PTR(void, address), byte_width));
+		return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
+	}
+
+	/* Exit if requested address is not within the protected port table */
+
+	if (address > acpi_protected_ports[ACPI_PORT_INFO_ENTRIES - 1].end) {
+		return_ACPI_STATUS(AE_OK);
+	}
+
+	/* Check request against the list of protected I/O ports */
+
+	for (i = 0; i < ACPI_PORT_INFO_ENTRIES; i++, port_info++) {
+		/*
+		 * Check if the requested address range will write to a reserved
+		 * port. Four cases to consider:
+		 *
+		 * 1) Address range is contained completely in the port address range
+		 * 2) Address range overlaps port range at the port range start
+		 * 3) Address range overlaps port range at the port range end
+		 * 4) Address range completely encompasses the port range
+		 */
+		if ((address <= port_info->end)
+		    && (last_address >= port_info->start)) {
+
+			/* Port illegality may depend on the _OSI calls made by the BIOS */
+
+			if (acpi_gbl_osi_data >= port_info->osi_dependency) {
+				ACPI_ERROR((AE_INFO,
+					    "Denied AML access to port 0x%p/%X (%s 0x%.4X-0x%.4X)",
+					    ACPI_CAST_PTR(void, address),
+					    byte_width, port_info->name,
+					    port_info->start, port_info->end));
+
+				return_ACPI_STATUS(AE_AML_ILLEGAL_ADDRESS);
+			}
+		}
+
+		/* Finished if address range ends before the end of this port */
+
+		if (last_address <= port_info->end) {
+			break;
+		}
+	}
+
+	return_ACPI_STATUS(AE_OK);
+}
+
+/******************************************************************************
+ *
+ * FUNCTION:    acpi_hw_read_port
+ *
+ * PARAMETERS:  Address             Address of I/O port/register to read
+ *              Value               Where value is placed
+ *              Width               Number of bits
+ *
+ * RETURN:      Value read from port
+ *
+ * DESCRIPTION: Read data from an I/O port or register. This is a front-end
+ *              to acpi_os_read_port that performs validation on both the port
+ *              address and the length.
+ *
+ *****************************************************************************/
+
+acpi_status acpi_hw_read_port(acpi_io_address address, u32 *value, u32 width)
+{
+	acpi_status status;
+
+	status = acpi_hw_validate_io_request(address, width);
+	if (ACPI_FAILURE(status)) {
+		return status;
+	}
+
+	status = acpi_os_read_port(address, value, width);
+	return status;
+}
+
+/******************************************************************************
+ *
+ * FUNCTION:    acpi_hw_write_port
+ *
+ * PARAMETERS:  Address             Address of I/O port/register to write
+ *              Value               Value to write
+ *              Width               Number of bits
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Write data to an I/O port or register. This is a front-end
+ *              to acpi_os_write_port that performs validation on both the port
+ *              address and the length.
+ *
+ *****************************************************************************/
+
+acpi_status acpi_hw_write_port(acpi_io_address address, u32 value, u32 width)
+{
+	acpi_status status;
+
+	status = acpi_hw_validate_io_request(address, width);
+	if (ACPI_FAILURE(status)) {
+		return status;
+	}
+
+	status = acpi_os_write_port(address, value, width);
+	return status;
+}