Implemented TPM2 support for tpm_pcr_read() by adding a new function tpm2_pcr_read_dev() that is called for TPM2 chipsets.
Signed-off-by: Jarkko Sakkinen <[email protected]> --- drivers/char/tpm/tpm-interface.c | 5 ++++- drivers/char/tpm/tpm.h | 21 ++++++++++++++++++++ drivers/char/tpm/tpm2-commands.c | 43 ++++++++++++++++++++++++++++++++++++++++ drivers/char/tpm/tpm2.h | 18 +++++++++++++++++ 4 files changed, 86 insertions(+), 1 deletion(-) diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 07a2fc5..4494b16 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -680,7 +680,10 @@ int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf) chip = tpm_chip_find_get(chip_num); if (chip == NULL) return -ENODEV; - rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf); + if (chip->tpm2) + rc = tpm2_pcr_read_dev(chip, pcr_idx, res_buf); + else + rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf); tpm_chip_put(chip); return rc; } diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index bda88aa..10d6731 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -298,6 +298,25 @@ struct tpm_startup_in { __be16 startup_type; } __packed; +struct tpm2_pcr_read_in { + __be32 pcr_selects_cnt; + __be16 hash_alg; + u8 pcr_select_size; + u8 pcr_select[TPM2_PCR_SELECT_MIN]; +} __packed; + + +struct tpm2_pcr_read_out { + __be32 update_cnt; + __be32 pcr_selects_cnt; + __be16 hash_alg; + u8 pcr_select_size; + u8 pcr_select[TPM2_PCR_SELECT_MIN]; + __be32 digests_cnt; + __be16 digest_size; + u8 digest[TPM_DIGEST_SIZE]; +} __packed; + typedef union { struct tpm_getcap_params_out getcap_out; struct tpm_readpubek_params_out readpubek_out; @@ -309,6 +328,8 @@ typedef union { struct tpm_getrandom_in getrandom_in; struct tpm_getrandom_out getrandom_out; struct tpm_startup_in startup_in; + struct tpm2_pcr_read_in tpm2_pcrread_in; + struct tpm2_pcr_read_out tpm2_pcrread_out; } tpm_cmd_params; struct tpm_cmd_t { diff --git a/drivers/char/tpm/tpm2-commands.c b/drivers/char/tpm/tpm2-commands.c index 14b3ae7..2fb553c 100644 --- a/drivers/char/tpm/tpm2-commands.c +++ b/drivers/char/tpm/tpm2-commands.c @@ -157,3 +157,46 @@ unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal) else return duration; } + +#define TPM2_PCR_READ_IN_SIZE \ + (sizeof(struct tpm_input_header) + \ + sizeof(struct tpm2_pcr_read_in)) + +static struct tpm_input_header tpm2_pcrread_header = { + .tag = cpu_to_be16(TPM2_ST_NO_SESSIONS), + .length = cpu_to_be32(TPM2_PCR_READ_IN_SIZE), + .ordinal = cpu_to_be32(TPM2_CC_PCR_READ) +}; + +int tpm2_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf) +{ + int rc; + struct tpm_cmd_t cmd; + u8 *buf; + int i, j; + + if (pcr_idx >= TPM2_PLATFORM_PCR) + return -EINVAL; + + cmd.header.in = tpm2_pcrread_header; + cmd.params.tpm2_pcrread_in.pcr_selects_cnt = cpu_to_be32(1); + cmd.params.tpm2_pcrread_in.hash_alg = cpu_to_be16(TPM2_ALG_SHA1); + cmd.params.tpm2_pcrread_in.pcr_select_size = TPM2_PCR_SELECT_MIN; + + for (i = 0; i < TPM2_PCR_SELECT_MIN; i++) { + j = pcr_idx - i * 8; + + cmd.params.tpm2_pcrread_in.pcr_select[i] = + (j >= 0 && j < 8) ? 1 << j : 0; + } + + rc = tpm_transmit_cmd(chip, &cmd, sizeof(cmd), + "attempting to read a pcr value"); + + if (rc == 0) { + buf = cmd.params.tpm2_pcrread_out.digest; + memcpy(res_buf, buf, TPM_DIGEST_SIZE); + } + + return rc; +} diff --git a/drivers/char/tpm/tpm2.h b/drivers/char/tpm/tpm2.h index dc0a2a2..fbab49c 100644 --- a/drivers/char/tpm/tpm2.h +++ b/drivers/char/tpm/tpm2.h @@ -16,11 +16,29 @@ #ifndef __DRIVERS_CHAR_TPM2_H__ #define __DRIVERS_CHAR_TPM2_H__ +enum tpm2_const { + TPM2_PLATFORM_PCR = 24, + TPM2_PCR_SELECT_MIN = ((TPM2_PLATFORM_PCR + 7) / 8), +}; + +enum tpm2_structures { + TPM2_ST_NO_SESSIONS = 0x8001, +}; + +enum tpm2_algorithms { + TPM2_ALG_SHA1 = 0x0004, +}; + +enum tpm2_command_codes { + TPM2_CC_PCR_READ = 0x017E, +}; + struct tpm_chip; #define TPM2_CC_FIRST 0x11F #define TPM2_CC_LAST 0x18F unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *, u32); +int tpm2_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf); #endif /* __DRIVERS_CHAR_TPM2_H__ */ -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
