diff options
Diffstat (limited to 'drivers/char/tpm')
-rw-r--r-- | drivers/char/tpm/tpm-chip.c | 24 | ||||
-rw-r--r-- | drivers/char/tpm/tpm-interface.c | 135 | ||||
-rw-r--r-- | drivers/char/tpm/tpm.h | 2 |
3 files changed, 86 insertions, 75 deletions
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index a114e8f7fb90..bab9c14e040c 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -81,21 +81,26 @@ void tpm_put_ops(struct tpm_chip *chip) EXPORT_SYMBOL_GPL(tpm_put_ops); /** - * tpm_chip_find_get() - return tpm_chip for a given chip number - * @chip_num: id to find + * tpm_chip_find_get() - find and reserve a TPM chip + * @chip: a &struct tpm_chip instance, %NULL for the default chip * - * The return'd chip has been tpm_try_get_ops'd and must be released via - * tpm_put_ops + * Finds a TPM chip and reserves its class device and operations. The chip must + * be released with tpm_chip_put_ops() after use. + * + * Return: + * A reserved &struct tpm_chip instance. + * %NULL if a chip is not found. + * %NULL if the chip is not available. */ -struct tpm_chip *tpm_chip_find_get(int chip_num) +struct tpm_chip *tpm_chip_find_get(struct tpm_chip *chip) { - struct tpm_chip *chip, *res = NULL; + struct tpm_chip *res = NULL; + int chip_num = 0; int chip_prev; mutex_lock(&idr_lock); - if (chip_num == TPM_ANY_NUM) { - chip_num = 0; + if (!chip) { do { chip_prev = chip_num; chip = idr_get_next(&dev_nums_idr, &chip_num); @@ -105,8 +110,7 @@ struct tpm_chip *tpm_chip_find_get(int chip_num) } } while (chip_prev != chip_num); } else { - chip = idr_find(&dev_nums_idr, chip_num); - if (chip && !tpm_try_get_ops(chip)) + if (!tpm_try_get_ops(chip)) res = chip; } diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index ebe0a1d36d8c..19f820f775b5 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -809,19 +809,20 @@ int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) } /** - * tpm_is_tpm2 - is the chip a TPM2 chip? - * @chip_num: tpm idx # or ANY + * tpm_is_tpm2 - do we a have a TPM2 chip? + * @chip: a &struct tpm_chip instance, %NULL for the default chip * - * Returns < 0 on error, and 1 or 0 on success depending whether the chip - * is a TPM2 chip. + * Return: + * 1 if we have a TPM2 chip. + * 0 if we don't have a TPM2 chip. + * A negative number for system errors (errno). */ -int tpm_is_tpm2(u32 chip_num) +int tpm_is_tpm2(struct tpm_chip *chip) { - struct tpm_chip *chip; int rc; - chip = tpm_chip_find_get(chip_num); - if (chip == NULL) + chip = tpm_chip_find_get(chip); + if (!chip) return -ENODEV; rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0; @@ -833,23 +834,19 @@ int tpm_is_tpm2(u32 chip_num) EXPORT_SYMBOL_GPL(tpm_is_tpm2); /** - * tpm_pcr_read - read a pcr value - * @chip_num: tpm idx # or ANY - * @pcr_idx: pcr idx to retrieve - * @res_buf: TPM_PCR value - * size of res_buf is 20 bytes (or NULL if you don't care) + * tpm_pcr_read - read a PCR value from SHA1 bank + * @chip: a &struct tpm_chip instance, %NULL for the default chip + * @pcr_idx: the PCR to be retrieved + * @res_buf: the value of the PCR * - * The TPM driver should be built-in, but for whatever reason it - * isn't, protect against the chip disappearing, by incrementing - * the module usage count. + * Return: same as with tpm_transmit_cmd() */ -int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf) +int tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) { - struct tpm_chip *chip; int rc; - chip = tpm_chip_find_get(chip_num); - if (chip == NULL) + chip = tpm_chip_find_get(chip); + if (!chip) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_TPM2) rc = tpm2_pcr_read(chip, pcr_idx, res_buf); @@ -889,25 +886,26 @@ static int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash, } /** - * tpm_pcr_extend - extend pcr value with hash - * @chip_num: tpm idx # or AN& - * @pcr_idx: pcr idx to extend - * @hash: hash value used to extend pcr value + * tpm_pcr_extend - extend a PCR value in SHA1 bank. + * @chip: a &struct tpm_chip instance, %NULL for the default chip + * @pcr_idx: the PCR to be retrieved + * @hash: the hash value used to extend the PCR value * - * The TPM driver should be built-in, but for whatever reason it - * isn't, protect against the chip disappearing, by incrementing - * the module usage count. + * Note: with TPM 2.0 extends also those banks with a known digest size to the + * cryto subsystem in order to prevent malicious use of those PCR banks. In the + * future we should dynamically determine digest sizes. + * + * Return: same as with tpm_transmit_cmd() */ -int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash) +int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash) { int rc; - struct tpm_chip *chip; struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; u32 count = 0; int i; - chip = tpm_chip_find_get(chip_num); - if (chip == NULL) + chip = tpm_chip_find_get(chip); + if (!chip) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_TPM2) { @@ -1019,17 +1017,24 @@ out: return rc; } -int tpm_send(u32 chip_num, void *cmd, size_t buflen) +/** + * tpm_send - send a TPM command + * @chip: a &struct tpm_chip instance, %NULL for the default chip + * @cmd: a TPM command buffer + * @buflen: the length of the TPM command buffer + * + * Return: same as with tpm_transmit_cmd() + */ +int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen) { - struct tpm_chip *chip; int rc; - chip = tpm_chip_find_get(chip_num); - if (chip == NULL) + chip = tpm_chip_find_get(chip); + if (!chip) return -ENODEV; rc = tpm_transmit_cmd(chip, NULL, cmd, buflen, 0, 0, - "attempting tpm_cmd"); + "attempting to a send a command"); tpm_put_ops(chip); return rc; } @@ -1127,16 +1132,15 @@ static const struct tpm_input_header tpm_getrandom_header = { }; /** - * tpm_get_random() - Get random bytes from the tpm's RNG - * @chip_num: A specific chip number for the request or TPM_ANY_NUM - * @out: destination buffer for the random bytes - * @max: the max number of bytes to write to @out + * tpm_get_random() - get random bytes from the TPM's RNG + * @chip: a &struct tpm_chip instance, %NULL for the default chip + * @out: destination buffer for the random bytes + * @max: the max number of bytes to write to @out * - * Returns < 0 on error and the number of bytes read on success + * Return: same as with tpm_transmit_cmd() */ -int tpm_get_random(u32 chip_num, u8 *out, size_t max) +int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max) { - struct tpm_chip *chip; struct tpm_cmd_t tpm_cmd; u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA), rlength; int err, total = 0, retries = 5; @@ -1145,8 +1149,8 @@ int tpm_get_random(u32 chip_num, u8 *out, size_t max) if (!out || !num_bytes || max > TPM_MAX_RNG_DATA) return -EINVAL; - chip = tpm_chip_find_get(chip_num); - if (chip == NULL) + chip = tpm_chip_find_get(chip); + if (!chip) return -ENODEV; if (chip->flags & TPM_CHIP_FLAG_TPM2) { @@ -1188,22 +1192,23 @@ int tpm_get_random(u32 chip_num, u8 *out, size_t max) EXPORT_SYMBOL_GPL(tpm_get_random); /** - * tpm_seal_trusted() - seal a trusted key - * @chip_num: A specific chip number for the request or TPM_ANY_NUM - * @options: authentication values and other options - * @payload: the key data in clear and encrypted form + * tpm_seal_trusted() - seal a trusted key payload + * @chip: a &struct tpm_chip instance, %NULL for the default chip + * @options: authentication values and other options + * @payload: the key data in clear and encrypted form + * + * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in + * the keyring subsystem. * - * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips - * are supported. + * Return: same as with tpm_transmit_cmd() */ -int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload, +int tpm_seal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options) { - struct tpm_chip *chip; int rc; - chip = tpm_chip_find_get(chip_num); - if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2)) + chip = tpm_chip_find_get(chip); + if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2)) return -ENODEV; rc = tpm2_seal_trusted(chip, payload, options); @@ -1215,21 +1220,23 @@ EXPORT_SYMBOL_GPL(tpm_seal_trusted); /** * tpm_unseal_trusted() - unseal a trusted key - * @chip_num: A specific chip number for the request or TPM_ANY_NUM - * @options: authentication values and other options - * @payload: the key data in clear and encrypted form + * @chip: a &struct tpm_chip instance, %NULL for the default chip + * @options: authentication values and other options + * @payload: the key data in clear and encrypted form + * + * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in + * the keyring subsystem. * - * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips - * are supported. + * Return: same as with tpm_transmit_cmd() */ -int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload, +int tpm_unseal_trusted(struct tpm_chip *chip, + struct trusted_key_payload *payload, struct trusted_key_options *options) { - struct tpm_chip *chip; int rc; - chip = tpm_chip_find_get(chip_num); - if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2)) + chip = tpm_chip_find_get(chip); + if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2)) return -ENODEV; rc = tpm2_unseal_trusted(chip, payload, options); diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index c1866cc02e30..6c189174c0d3 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -516,7 +516,7 @@ static inline void tpm_msleep(unsigned int delay_msec) delay_msec * 1000); }; -struct tpm_chip *tpm_chip_find_get(int chip_num); +struct tpm_chip *tpm_chip_find_get(struct tpm_chip *chip); __must_check int tpm_try_get_ops(struct tpm_chip *chip); void tpm_put_ops(struct tpm_chip *chip); |