From 6719cbe31afef2cba4bc10b33350b38c4a51c3ac Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Sat, 6 Feb 2021 14:23:40 -0700 Subject: [PATCH] tpm: Add TPM2 support for read/write values Implement this API function for TPM2. Signed-off-by: Simon Glass Acked-by: Ilias Apalodimas --- include/tpm-common.h | 3 ++ include/tpm-v2.h | 38 ++++++++++++++++++++ lib/tpm-v2.c | 84 ++++++++++++++++++++++++++++++++++++++++++++ lib/tpm_api.c | 4 +-- 4 files changed, 127 insertions(+), 2 deletions(-) diff --git a/include/tpm-common.h b/include/tpm-common.h index c1309a2735..998b4fbb41 100644 --- a/include/tpm-common.h +++ b/include/tpm-common.h @@ -55,6 +55,8 @@ enum tpm_version { * @buf: Buffer used during the exchanges with the chip * @pcr_count: Number of PCR per bank * @pcr_select_min: Minimum size in bytes of the pcrSelect array + * @plat_hier_disabled: Platform hierarchy has been disabled (TPM is locked + * down until next reboot) */ struct tpm_chip_priv { enum tpm_version version; @@ -66,6 +68,7 @@ struct tpm_chip_priv { /* TPM v2 specific data */ uint pcr_count; uint pcr_select_min; + bool plat_hier_disabled; }; /** diff --git a/include/tpm-v2.h b/include/tpm-v2.h index aa8b6512b2..b73a2d278e 100644 --- a/include/tpm-v2.h +++ b/include/tpm-v2.h @@ -242,6 +242,7 @@ enum tpm2_command_codes { TPM2_CC_HIERCHANGEAUTH = 0x0129, TPM2_CC_NV_DEFINE_SPACE = 0x012a, TPM2_CC_PCR_SETAUTHPOL = 0x012C, + TPM2_CC_NV_WRITE = 0x0137, TPM2_CC_DAM_RESET = 0x0139, TPM2_CC_DAM_PARAMETERS = 0x013A, TPM2_CC_NV_READ = 0x014E, @@ -356,6 +357,20 @@ enum { TPM_MAX_BUF_SIZE = 1260, }; +enum { + /* Secure storage for firmware settings */ + TPM_HT_PCR = 0, + TPM_HT_NV_INDEX, + TPM_HT_HMAC_SESSION, + TPM_HT_POLICY_SESSION, + + HR_SHIFT = 24, + HR_PCR = TPM_HT_PCR << HR_SHIFT, + HR_HMAC_SESSION = TPM_HT_HMAC_SESSION << HR_SHIFT, + HR_POLICY_SESSION = TPM_HT_POLICY_SESSION << HR_SHIFT, + HR_NV_INDEX = TPM_HT_NV_INDEX << HR_SHIFT, +}; + /** * Issue a TPM2_Startup command. * @@ -420,6 +435,29 @@ u32 tpm2_nv_define_space(struct udevice *dev, u32 space_index, u32 tpm2_pcr_extend(struct udevice *dev, u32 index, u32 algorithm, const u8 *digest, u32 digest_len); +/** + * Read data from the secure storage + * + * @dev TPM device + * @index Index of data to read + * @data Place to put data + * @count Number of bytes of data + * @return code of the operation + */ +u32 tpm2_nv_read_value(struct udevice *dev, u32 index, void *data, u32 count); + +/** + * Write data to the secure storage + * + * @dev TPM device + * @index Index of data to write + * @data Data to write + * @count Number of bytes of data + * @return code of the operation + */ +u32 tpm2_nv_write_value(struct udevice *dev, u32 index, const void *data, + u32 count); + /** * Issue a TPM2_PCR_Read command. * diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c index e9bf4018fe..9f1699131e 100644 --- a/lib/tpm-v2.c +++ b/lib/tpm-v2.c @@ -169,6 +169,90 @@ u32 tpm2_pcr_extend(struct udevice *dev, u32 index, u32 algorithm, return tpm_sendrecv_command(dev, command_v2, NULL, NULL); } +u32 tpm2_nv_read_value(struct udevice *dev, u32 index, void *data, u32 count) +{ + u8 command_v2[COMMAND_BUFFER_SIZE] = { + /* header 10 bytes */ + tpm_u16(TPM2_ST_SESSIONS), /* TAG */ + tpm_u32(10 + 8 + 4 + 9 + 4), /* Length */ + tpm_u32(TPM2_CC_NV_READ), /* Command code */ + + /* handles 8 bytes */ + tpm_u32(TPM2_RH_PLATFORM), /* Primary platform seed */ + tpm_u32(HR_NV_INDEX + index), /* Password authorisation */ + + /* AUTH_SESSION */ + tpm_u32(9), /* Authorization size */ + tpm_u32(TPM2_RS_PW), /* Session handle */ + tpm_u16(0), /* Size of */ + /* (if any) */ + 0, /* Attributes: Cont/Excl/Rst */ + tpm_u16(0), /* Size of */ + /* (if any) */ + + tpm_u16(count), /* Number of bytes */ + tpm_u16(0), /* Offset */ + }; + size_t response_len = COMMAND_BUFFER_SIZE; + u8 response[COMMAND_BUFFER_SIZE]; + int ret; + u16 tag; + u32 size, code; + + ret = tpm_sendrecv_command(dev, command_v2, response, &response_len); + if (ret) + return log_msg_ret("read", ret); + if (unpack_byte_string(response, response_len, "wdds", + 0, &tag, 2, &size, 6, &code, + 16, data, count)) + return TPM_LIB_ERROR; + + return 0; +} + +u32 tpm2_nv_write_value(struct udevice *dev, u32 index, const void *data, + u32 count) +{ + struct tpm_chip_priv *priv = dev_get_uclass_priv(dev); + uint offset = 10 + 8 + 4 + 9 + 2; + uint len = offset + count + 2; + /* Use empty password auth if platform hierarchy is disabled */ + u32 auth = priv->plat_hier_disabled ? HR_NV_INDEX + index : + TPM2_RH_PLATFORM; + u8 command_v2[COMMAND_BUFFER_SIZE] = { + /* header 10 bytes */ + tpm_u16(TPM2_ST_SESSIONS), /* TAG */ + tpm_u32(len), /* Length */ + tpm_u32(TPM2_CC_NV_WRITE), /* Command code */ + + /* handles 8 bytes */ + tpm_u32(auth), /* Primary platform seed */ + tpm_u32(HR_NV_INDEX + index), /* Password authorisation */ + + /* AUTH_SESSION */ + tpm_u32(9), /* Authorization size */ + tpm_u32(TPM2_RS_PW), /* Session handle */ + tpm_u16(0), /* Size of */ + /* (if any) */ + 0, /* Attributes: Cont/Excl/Rst */ + tpm_u16(0), /* Size of */ + /* (if any) */ + + tpm_u16(count), + }; + size_t response_len = COMMAND_BUFFER_SIZE; + u8 response[COMMAND_BUFFER_SIZE]; + int ret; + + ret = pack_byte_string(command_v2, sizeof(command_v2), "sw", + offset, data, count, + offset + count, 0); + if (ret) + return TPM_LIB_ERROR; + + return tpm_sendrecv_command(dev, command_v2, response, &response_len); +} + u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz, void *data, unsigned int *updates) { diff --git a/lib/tpm_api.c b/lib/tpm_api.c index f1553512cc..687fc8bc7e 100644 --- a/lib/tpm_api.c +++ b/lib/tpm_api.c @@ -118,7 +118,7 @@ u32 tpm_nv_read_value(struct udevice *dev, u32 index, void *data, u32 count) if (is_tpm1(dev)) return tpm1_nv_read_value(dev, index, data, count); else if (is_tpm2(dev)) - return -ENOSYS; + return tpm2_nv_read_value(dev, index, data, count); else return -ENOSYS; } @@ -129,7 +129,7 @@ u32 tpm_nv_write_value(struct udevice *dev, u32 index, const void *data, if (is_tpm1(dev)) return tpm1_nv_write_value(dev, index, data, count); else if (is_tpm2(dev)) - return -ENOSYS; + return tpm2_nv_write_value(dev, index, data, count); else return -ENOSYS; } -- 2.39.5