diff options
Diffstat (limited to 'drivers/char/tpm/tpm1-cmd.c')
| -rw-r--r-- | drivers/char/tpm/tpm1-cmd.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c index e02f0c1c822f..a69a02366c32 100644 --- a/drivers/char/tpm/tpm1-cmd.c +++ b/drivers/char/tpm/tpm1-cmd.c @@ -524,3 +524,145 @@ int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max) return total ? total : -EIO; } + +#define TPM_ORDINAL_PCRREAD 21 +#define READ_PCR_RESULT_SIZE 30 +#define READ_PCR_RESULT_BODY_SIZE 20 +static const struct tpm_input_header pcrread_header = { + .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), + .length = cpu_to_be32(14), + .ordinal = cpu_to_be32(TPM_ORDINAL_PCRREAD) +}; + +int tpm1_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) +{ + int rc; + struct tpm_cmd_t cmd; + + cmd.header.in = pcrread_header; + cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx); + rc = tpm_transmit_cmd(chip, NULL, &cmd, READ_PCR_RESULT_SIZE, + READ_PCR_RESULT_BODY_SIZE, 0, + "attempting to read a pcr value"); + + if (rc == 0) + memcpy(res_buf, cmd.params.pcrread_out.pcr_result, + TPM_DIGEST_SIZE); + return rc; +} + +#define TPM_ORD_CONTINUE_SELFTEST 83 +#define CONTINUE_SELFTEST_RESULT_SIZE 10 +static const struct tpm_input_header continue_selftest_header = { + .tag = cpu_to_be16(TPM_TAG_RQU_COMMAND), + .length = cpu_to_be32(10), + .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST), +}; + +/** + * tpm_continue_selftest -- run TPM's selftest + * @chip: TPM chip to use + * + * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing + * a TPM error code. + */ +static int tpm1_continue_selftest(struct tpm_chip *chip) +{ + int rc; + struct tpm_cmd_t cmd; + + cmd.header.in = continue_selftest_header; + rc = tpm_transmit_cmd(chip, NULL, &cmd, CONTINUE_SELFTEST_RESULT_SIZE, + 0, 0, "continue selftest"); + return rc; +} + +/** + * tpm1_do_selftest - have the TPM continue its selftest and wait until it + * can receive further commands + * @chip: TPM chip to use + * + * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing + * a TPM error code. + */ +int tpm1_do_selftest(struct tpm_chip *chip) +{ + int rc; + unsigned int loops; + unsigned int delay_msec = 100; + unsigned long duration; + u8 dummy[TPM_DIGEST_SIZE]; + + duration = tpm1_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST); + + loops = jiffies_to_msecs(duration) / delay_msec; + + rc = tpm1_continue_selftest(chip); + if (rc == TPM_ERR_INVALID_POSTINIT) { + chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED; + dev_info(&chip->dev, "TPM not ready (%d)\n", rc); + } + /* This may fail if there was no TPM driver during a suspend/resume + * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST) + */ + if (rc) + return rc; + + do { + /* Attempt to read a PCR value */ + rc = tpm1_pcr_read_dev(chip, 0, dummy); + + /* Some buggy TPMs will not respond to tpm_tis_ready() for + * around 300ms while the self test is ongoing, keep trying + * until the self test duration expires. + */ + if (rc == -ETIME) { + dev_info(&chip->dev, HW_ERR "TPM command timed out during continue self test"); + tpm_msleep(delay_msec); + continue; + } + + if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) { + dev_info(&chip->dev, "TPM is disabled/deactivated (0x%X)\n", + rc); + /* TPM is disabled and/or deactivated; driver can + * proceed and TPM does handle commands for + * suspend/resume correctly + */ + return 0; + } + if (rc != TPM_WARN_DOING_SELFTEST) + return rc; + tpm_msleep(delay_msec); + } while (--loops > 0); + + return rc; +} +EXPORT_SYMBOL_GPL(tpm1_do_selftest); + +/** + * tpm1_auto_startup - Perform the standard automatic TPM initialization + * sequence + * @chip: TPM chip to use + * + * Returns 0 on success, < 0 in case of fatal error. + */ +int tpm1_auto_startup(struct tpm_chip *chip) +{ + int rc; + + rc = tpm1_get_timeouts(chip); + if (rc) + goto out; + rc = tpm1_do_selftest(chip); + if (rc) { + dev_err(&chip->dev, "TPM self test failed\n"); + goto out; + } + + return rc; +out: + if (rc > 0) + rc = -ENODEV; + return rc; +} |