u-boot/include/tpm-common.h
Miquel Raynal 2a2096ea60 tpm: allow TPM v1 and v2 to be compiled at the same time
While there is probably no reason to do so in a real life situation, it
will allow to compile test both stacks with the same sandbox defconfig.

As we cannot define two 'tpm' commands at the same time, the command for
TPM v1 is still called 'tpm' and the one for TPM v2 'tpm2'. While this
is the exact command name that must be written into eg. test files, any
user already using the TPM v2 stack can continue to do so by just writing
'tpm' because as long as TPM v1 support is not compiled, U-Boot prompt
will search for the closest command named after 'tpm'.

The command set can also be changed at runtime (not supported yet, but
ready to be), but as one can compile only either one stack or the other,
there is still one spot in the code where conditionals are used: to
retrieve the v1 or v2 command set.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
[trini: In sandbox_tpm2_fill_buf() use NULL not \0 to ensure NULL
terminated string due to LLVM warning]
Signed-off-by: Tom Rini <trini@konsulko.com>
2018-07-28 11:57:38 -04:00

245 lines
6.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (c) 2013 The Chromium OS Authors.
* Coypright (c) 2013 Guntermann & Drunck GmbH
*/
#ifndef __TPM_COMMON_H
#define __TPM_COMMON_H
enum tpm_duration {
TPM_SHORT = 0,
TPM_MEDIUM = 1,
TPM_LONG = 2,
TPM_UNDEFINED,
TPM_DURATION_COUNT,
};
/*
* Here is a partial implementation of TPM commands. Please consult TCG Main
* Specification for definitions of TPM commands.
*/
#define TPM_HEADER_SIZE 10
/* Max buffer size supported by our tpm */
#define TPM_DEV_BUFSIZE 1260
/**
* enum tpm_version - The version of the TPM stack to be used
* @TPM_V1: Use TPM v1.x stack
* @TPM_V2: Use TPM v2.x stack
*/
enum tpm_version {
TPM_V1 = 0,
TPM_V2,
};
/**
* struct tpm_chip_priv - Information about a TPM, stored by the uclass
*
* These values must be set up by the device's probe() method before
* communcation is attempted. If the device has an xfer() method, this is
* not needed. There is no need to set up @buf.
*
* @version: TPM stack to be used
* @duration_ms: Length of each duration type in milliseconds
* @retry_time_ms: Time to wait before retrying receive
* @buf: Buffer used during the exchanges with the chip
* @pcr_count: Number of PCR per bank
* @pcr_select_min: Minimum size in bytes of the pcrSelect array
*/
struct tpm_chip_priv {
enum tpm_version version;
uint duration_ms[TPM_DURATION_COUNT];
uint retry_time_ms;
u8 buf[TPM_DEV_BUFSIZE + sizeof(u8)]; /* Max buffer size + addr */
/* TPM v2 specific data */
uint pcr_count;
uint pcr_select_min;
};
/**
* struct tpm_ops - low-level TPM operations
*
* These are designed to avoid loops and delays in the driver itself. These
* should be handled in the uclass.
*
* In gneral you should implement everything except xfer(). Where you need
* complete control of the transfer, then xfer() can be provided and will
* override the other methods.
*
* This interface is for low-level TPM access. It does not understand the
* concept of localities or the various TPM messages. That interface is
* defined in the functions later on in this file, but they all translate
* to bytes which are sent and received.
*/
struct tpm_ops {
/**
* open() - Request access to locality 0 for the caller
*
* After all commands have been completed the caller should call
* close().
*
* @dev: Device to open
* @return 0 ok OK, -ve on error
*/
int (*open)(struct udevice *dev);
/**
* close() - Close the current session
*
* Releasing the locked locality. Returns 0 on success, -ve 1 on
* failure (in case lock removal did not succeed).
*
* @dev: Device to close
* @return 0 ok OK, -ve on error
*/
int (*close)(struct udevice *dev);
/**
* get_desc() - Get a text description of the TPM
*
* @dev: Device to check
* @buf: Buffer to put the string
* @size: Maximum size of buffer
* @return length of string, or -ENOSPC it no space
*/
int (*get_desc)(struct udevice *dev, char *buf, int size);
/**
* send() - send data to the TPM
*
* @dev: Device to talk to
* @sendbuf: Buffer of the data to send
* @send_size: Size of the data to send
*
* Returns 0 on success or -ve on failure.
*/
int (*send)(struct udevice *dev, const u8 *sendbuf, size_t send_size);
/**
* recv() - receive a response from the TPM
*
* @dev: Device to talk to
* @recvbuf: Buffer to save the response to
* @max_size: Maximum number of bytes to receive
*
* Returns number of bytes received on success, -EAGAIN if the TPM
* response is not ready, -EINTR if cancelled, or other -ve value on
* failure.
*/
int (*recv)(struct udevice *dev, u8 *recvbuf, size_t max_size);
/**
* cleanup() - clean up after an operation in progress
*
* This is called if receiving times out. The TPM may need to abort
* the current transaction if it did not complete, and make itself
* ready for another.
*
* @dev: Device to talk to
*/
int (*cleanup)(struct udevice *dev);
/**
* xfer() - send data to the TPM and get response
*
* This method is optional. If it exists it is used in preference
* to send(), recv() and cleanup(). It should handle all aspects of
* TPM communication for a single transfer.
*
* @dev: Device to talk to
* @sendbuf: Buffer of the data to send
* @send_size: Size of the data to send
* @recvbuf: Buffer to save the response to
* @recv_size: Pointer to the size of the response buffer
*
* Returns 0 on success (and places the number of response bytes at
* recv_size) or -ve on failure.
*/
int (*xfer)(struct udevice *dev, const u8 *sendbuf, size_t send_size,
u8 *recvbuf, size_t *recv_size);
};
#define tpm_get_ops(dev) ((struct tpm_ops *)device_get_ops(dev))
#define MAKE_TPM_CMD_ENTRY(cmd) \
U_BOOT_CMD_MKENT(cmd, 0, 1, do_tpm_ ## cmd, "", "")
#define TPM_COMMAND_NO_ARG(cmd) \
int do_##cmd(cmd_tbl_t *cmdtp, int flag, \
int argc, char * const argv[]) \
{ \
if (argc != 1) \
return CMD_RET_USAGE; \
return report_return_code(cmd()); \
}
/**
* tpm_get_desc() - Get a text description of the TPM
*
* @dev: Device to check
* @buf: Buffer to put the string
* @size: Maximum size of buffer
* @return length of string, or -ENOSPC it no space
*/
int tpm_get_desc(struct udevice *dev, char *buf, int size);
/**
* tpm_xfer() - send data to the TPM and get response
*
* This first uses the device's send() method to send the bytes. Then it calls
* recv() to get the reply. If recv() returns -EAGAIN then it will delay a
* short time and then call recv() again.
*
* Regardless of whether recv() completes successfully, it will then call
* cleanup() to finish the transaction.
*
* Note that the outgoing data is inspected to determine command type
* (ordinal) and a timeout is used for that command type.
*
* @sendbuf - buffer of the data to send
* @send_size size of the data to send
* @recvbuf - memory to save the response to
* @recv_len - pointer to the size of the response buffer
*
* Returns 0 on success (and places the number of response bytes at
* recv_len) or -ve on failure.
*/
int tpm_xfer(struct udevice *dev, const u8 *sendbuf, size_t send_size,
u8 *recvbuf, size_t *recv_size);
/**
* Initialize TPM device. It must be called before any TPM commands.
*
* @return 0 on success, non-0 on error.
*/
int tpm_init(void);
/**
* Retrieve the array containing all the v1 (resp. v2) commands.
*
* @return a cmd_tbl_t array.
*/
#if defined(CONFIG_TPM_V1)
cmd_tbl_t *get_tpm1_commands(unsigned int *size);
#else
static inline cmd_tbl_t *get_tpm1_commands(unsigned int *size)
{
return NULL;
}
#endif
#if defined(CONFIG_TPM_V2)
cmd_tbl_t *get_tpm2_commands(unsigned int *size);
#else
static inline cmd_tbl_t *get_tpm2_commands(unsigned int *size)
{
return NULL;
}
#endif
#endif /* __TPM_COMMON_H */