diff options
Diffstat (limited to 'drivers/char/tpm/tpm-interface.c')
-rw-r--r-- | drivers/char/tpm/tpm-interface.c | 58 |
1 files changed, 7 insertions, 51 deletions
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index a94a88f9f91c..a2205f26c74c 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -811,14 +811,6 @@ int tpm_pm_resume(struct device *dev) } EXPORT_SYMBOL_GPL(tpm_pm_resume); -#define TPM_ORD_GET_RANDOM 70 -#define TPM_GETRANDOM_RESULT_SIZE 18 -static const struct tpm_input_header tpm_getrandom_header = { - .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), - .length = cpu_to_be32(14), - .ordinal = cpu_to_be32(TPM_ORD_GET_RANDOM) -}; - /** * tpm_get_random() - get random bytes from the TPM's RNG * @chip: a &struct tpm_chip instance, %NULL for the default chip @@ -829,58 +821,22 @@ static const struct tpm_input_header tpm_getrandom_header = { */ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max) { - 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; - u8 *dest = out; + int rc; - if (!out || !num_bytes || max > TPM_MAX_RNG_DATA) + if (!out || max > TPM_MAX_RNG_DATA) return -EINVAL; chip = tpm_find_get_ops(chip); if (!chip) return -ENODEV; - if (chip->flags & TPM_CHIP_FLAG_TPM2) { - err = tpm2_get_random(chip, out, max); - tpm_put_ops(chip); - return err; - } - - do { - tpm_cmd.header.in = tpm_getrandom_header; - tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes); - - err = tpm_transmit_cmd(chip, NULL, &tpm_cmd, - TPM_GETRANDOM_RESULT_SIZE + num_bytes, - offsetof(struct tpm_getrandom_out, - rng_data), - 0, "attempting get random"); - if (err) - break; - - recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len); - if (recd > num_bytes) { - total = -EFAULT; - break; - } - - rlength = be32_to_cpu(tpm_cmd.header.out.length); - if (rlength < TPM_HEADER_SIZE + - offsetof(struct tpm_getrandom_out, rng_data) + - recd) { - total = -EFAULT; - break; - } - memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd); - - dest += recd; - total += recd; - num_bytes -= recd; - } while (retries-- && total < max); + if (chip->flags & TPM_CHIP_FLAG_TPM2) + rc = tpm2_get_random(chip, out, max); + else + rc = tpm1_get_random(chip, out, max); tpm_put_ops(chip); - return total ? total : -EIO; + return rc; } EXPORT_SYMBOL_GPL(tpm_get_random); |