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Diffstat (limited to 'drivers/mxc/security/dryice.h')
-rw-r--r-- | drivers/mxc/security/dryice.h | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/drivers/mxc/security/dryice.h b/drivers/mxc/security/dryice.h new file mode 100644 index 000000000000..127e0bcd5d1b --- /dev/null +++ b/drivers/mxc/security/dryice.h @@ -0,0 +1,287 @@ +/* + * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + + +#ifndef __DRYICE_H__ +#define __DRYICE_H__ + + +/*! + * @file dryice.h + * @brief Definition of DryIce API. + */ + +/*! @page dryice_api DryIce API + * + * Definition of the DryIce API. + * + * The DryIce API implements a software interface to the DryIce hardware + * block. Methods are provided to store, retrieve, generate, and manage + * cryptographic keys and to monitor security tamper events. + * + * See @ref dryice_api for the DryIce API. + */ + +/*! + * This defines the SCC key length (in bits) + */ +#define SCC_KEY_LEN 168 + +/*! + * This defines the maximum key length (in bits) + */ +#define MAX_KEY_LEN 256 +#define MAX_KEY_BYTES ((MAX_KEY_LEN) / 8) +#define MAX_KEY_WORDS ((MAX_KEY_LEN) / 32) + +/*! + * @name DryIce Function Flags + */ +/*@{*/ +#define DI_FUNC_FLAG_ASYNC 0x01 /*!< do not block */ +#define DI_FUNC_FLAG_READ_LOCK 0x02 /*!< set read lock for this resource */ +#define DI_FUNC_FLAG_WRITE_LOCK 0x04 /*!< set write lock for resource */ +#define DI_FUNC_FLAG_HARD_LOCK 0x08 /*!< locks will be hard (default soft) */ +#define DI_FUNC_FLAG_WORD_KEY 0x10 /*!< key provided as 32-bit words */ +/*@}*/ + +/*! + * @name DryIce Tamper Events + */ +/*@{*/ +#define DI_TAMPER_EVENT_WTD (1 << 23) /*!< wire-mesh tampering det */ +#define DI_TAMPER_EVENT_ETBD (1 << 22) /*!< ext tampering det: input B */ +#define DI_TAMPER_EVENT_ETAD (1 << 21) /*!< ext tampering det: input A */ +#define DI_TAMPER_EVENT_EBD (1 << 20) /*!< external boot detected */ +#define DI_TAMPER_EVENT_SAD (1 << 19) /*!< security alarm detected */ +#define DI_TAMPER_EVENT_TTD (1 << 18) /*!< temperature tampering det */ +#define DI_TAMPER_EVENT_CTD (1 << 17) /*!< clock tampering det */ +#define DI_TAMPER_EVENT_VTD (1 << 16) /*!< voltage tampering det */ +#define DI_TAMPER_EVENT_MCO (1 << 3) /*!< monotonic counter overflow */ +#define DI_TAMPER_EVENT_TCO (1 << 2) /*!< time counter overflow */ +/*@}*/ + +/*! + * DryIce Key Sources + */ +typedef enum di_key { + DI_KEY_FK, /*!< the fused (IIM) key */ + DI_KEY_PK, /*!< the programmed key */ + DI_KEY_RK, /*!< the random key */ + DI_KEY_FPK, /*!< the programmed key XORed with the fused key */ + DI_KEY_FRK, /*!< the random key XORed with the fused key */ +} di_key_t; + +/*! + * DryIce Error Codes + */ +typedef enum dryice_return { + DI_SUCCESS = 0, /*!< operation was successful */ + DI_ERR_BUSY, /*!< device or resource busy */ + DI_ERR_STATE, /*!< dryice is in incompatible state */ + DI_ERR_INUSE, /*!< resource is already in use */ + DI_ERR_UNSET, /*!< resource has not been initialized */ + DI_ERR_WRITE, /*!< error occurred during register write */ + DI_ERR_INVAL, /*!< invalid argument */ + DI_ERR_FAIL, /*!< operation failed */ + DI_ERR_HLOCK, /*!< resource is hard locked */ + DI_ERR_SLOCK, /*!< resource is soft locked */ + DI_ERR_NOMEM, /*!< out of memory */ +} di_return_t; + +/*! + * These functions define the DryIce API. + */ + +/*! + * Write a given key to the Programmed Key registers in DryIce, and + * optionally lock the Programmed Key against either reading or further + * writing. The value is held until a call to the release_programmed_key + * interface is made, or until the appropriate HW reset if the write-lock + * flags are used. Unused key bits will be zeroed. + * + * @param[in] key_data A pointer to the key data to be programmed, with + * the most significant byte or word first. This + * will be interpreted as a byte pointer unless the + * WORD_KEY flag is set, in which case it will be + * treated as a word pointer and the key data will be + * read a word at a time, starting with the MSW. + * When called asynchronously, the data pointed to by + * key_data must persist until the operation completes. + * + * @param[in] key_bits The number of bits in the key to be stored. + * This must be a multiple of 8 and within the + * range of 0 and MAX_KEY_LEN. + * + * @param[in] flags This is a bit-wise OR of the flags to be passed + * to the function. Flags can include: + * ASYNC, READ_LOCK, WRITE_LOCK, HARD_LOCK, and + * WORD_KEY. + * + * @return Returns SUCCESS (0), BUSY if DryIce is busy, INVAL + * on invalid arguments, INUSE if key has already been + * programmed, STATE if DryIce is in the wrong state, + * HLOCK or SLOCK if the key registers are locked for + * writing, and WRITE if a write error occurs + * (See #di_return_t). + */ +extern di_return_t dryice_set_programmed_key(const void *key_data, int key_bits, + int flags); + +/*! + * Read the Programmed Key registers and write the contents into a buffer. + * + * @param[out] key_data A byte pointer to where the key data will be written, + * with the most significant byte being written first. + * + * @param[in] key_bits The number of bits of the key to be retrieved. + * This must be a multiple of 8 and within the + * range of 0 and MAX_KEY_LEN. + * + * @return Returns SUCCESS (0), BUSY if DryIce is busy, INVAL + * on invalid arguments, UNSET if key has not been + * programmed, STATE if DryIce is in the wrong state, + * and HLOCK or SLOCK if the key registers are locked for + * reading (See #di_return_t). + */ +extern di_return_t dryice_get_programmed_key(uint8_t *key_data, int key_bits); + +/*! + * Allow the set_programmed_key interface to be used to write a new + * Programmed Key to DryIce. Note that this interface does not overwrite + * the value in the Programmed Key registers. + * + * @return Returns SUCCESS (0), BUSY if DryIce is busy, + * UNSET if the key has not been previously set, and + * HLOCK or SLOCK if the key registers are locked for + * writing (See #di_return_t). + */ +extern di_return_t dryice_release_programmed_key(void); + +/*! + * Generate and load a new Random Key in DryIce, and optionally lock the + * Random Key against further change. + * + * @param[in] flags This is a bit-wise OR of the flags to be passed + * to the function. Flags can include: + * ASYNC, READ_LOCK, WRITE_LOCK, and HARD_LOCK. + * + * @return Returns SUCCESS (0), BUSY if DryIce is busy, STATE + * if DryIce is in the wrong state, FAIL if the key gen + * failed, HLOCK or SLOCK if the key registers are + * locked, and WRITE if a write error occurs + * (See #di_return_t). + */ +extern di_return_t dryice_set_random_key(int flags); + +/*! + * Set the key selection in DryIce to determine the key used by an + * encryption module such as SCC. The selection is held until a call to the + * Release Selected Key interface is made, or until the appropriate HW + * reset if the LOCK flags are used. + * + * @param[in] key The source of the key to be used by the SCC + * (See #di_key_t). + * + * @param[in] flags This is a bit-wise OR of the flags to be passed + * to the function. Flags can include: + * ASYNC, WRITE_LOCK, and HARD_LOCK. + * + * @return Returns SUCCESS (0), BUSY if DryIce is busy, INVAL + * on invalid arguments, INUSE if a selection has already + * been made, STATE if DryIce is in the wrong state, + * HLOCK or SLOCK if the selection register is locked, + * and WRITE if a write error occurs + */ +extern di_return_t dryice_select_key(di_key_t key, int flags); + +/*! + * Check which key will be used in the SCC. This is needed because in some + * DryIce states, the Key Select Register is overridden by a default value + * (the Fused/IIM key). + * + * @param[out] key The source of the key that is currently selected for + * use by the SCC. This may be different from the key + * specified by the dryice_select_key function + * (See #di_key_t). This value is set even if an error + * code (except for BUSY) is returned. + * + * @return Returns SUCCESS (0), BUSY if DryIce is busy, STATE if + * DryIce is in the wrong state, INVAL on invalid + * arguments, or UNSET if no key has been selected + * (See #di_return_t). + */ +extern di_return_t dryice_check_key(di_key_t *key); + +/*! + * Allow the dryice_select_key interface to be used to set a new key selection + * in DryIce. Note that this interface does not overwrite the value in DryIce. + * + * @return Returns SUCCESS (0), BUSY if DryIce is busy, UNSET + * if the no selection has been made previously, and + * HLOCK or SLOCK if the selection register is locked + * (See #di_return_t). + */ +extern di_return_t dryice_release_key_selection(void); + +/*! + * Returns tamper-detection status bits. Also an optional timestamp when + * DryIce is in the Non-valid state. If DryIce is not in Failure or Non-valid + * state, this interface returns a failure code. + * + * @param[out] events This is a bit-wise OR of the following events: + * WTD (Wire Mesh), ETBD (External Tamper B), + * ETAD (External Tamper A), EBD (External Boot), + * SAD (Security Alarm), TTD (Temperature Tamper), + * CTD (Clock Tamper), VTD (Voltage Tamper), + * MCO (Monolithic Counter Overflow), and + * TCO (Time Counter Overflow). + * + * @param[out] timestamp This is the value of the time counter in seconds + * when the tamper occurred. A timestamp will not be + * returned if a NULL pointer is specified. If DryIce + * is not in the Non-valid state the time cannot be + * read, so a timestamp of 0 will be returned. + * + * @param[in] flags This is a bit-wise OR of the flags to be passed + * to the function. Flags is ignored currently by + * this function. + * + * @return Returns SUCCESS (0), BUSY if DryIce is busy, and + * INVAL on invalid arguments (See #di_return_t). + */ +extern di_return_t +dryice_get_tamper_event(uint32_t *events, uint32_t *timestamp, int flags); + +/*! + * Provide a callback function to be called upon the completion of DryIce calls + * that are executed asynchronously. + * + * @param[in] func This is a pointer to a function of type: + * void callback(di_return_t rc, unsigned long cookie) + * The return code of the async function is passed + * back in "rc" along with the cookie provided when + * registering the callback. + * + * @param[in] cookie This is an "opaque" cookie of type unsigned long that + * is returned on subsequent callbacks. It may be of any + * value. + * + * @return Returns SUCCESS (0), or BUSY if DryIce is busy + * (See #di_return_t). + */ +extern di_return_t dryice_register_callback(void (*func)(di_return_t rc, + unsigned long cookie), + unsigned long cookie); + +#endif /* __DRYICE_H__ */ |