From 27184f8905ba680f22abf1707fbed24036a67119 Mon Sep 17 00:00:00 2001 From: Jarkko Sakkinen Date: Wed, 13 Nov 2024 07:54:12 +0200 Subject: tpm: Opt-in in disable PCR integrity protection The initial HMAC session feature added TPM bus encryption and/or integrity protection to various in-kernel TPM operations. This can cause performance bottlenecks with IMA, as it heavily utilizes PCR extend operations. In order to mitigate this performance issue, introduce a kernel command-line parameter to the TPM driver for disabling the integrity protection for PCR extend operations (i.e. TPM2_PCR_Extend). Cc: James Bottomley Link: https://lore.kernel.org/linux-integrity/20241015193916.59964-1-zohar@linux.ibm.com/ Fixes: 6519fea6fd37 ("tpm: add hmac checks to tpm2_pcr_extend()") Tested-by: Mimi Zohar Co-developed-by: Roberto Sassu Signed-off-by: Roberto Sassu Co-developed-by: Mimi Zohar Signed-off-by: Mimi Zohar Signed-off-by: Jarkko Sakkinen --- include/linux/tpm.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 587b96b4418e..20a40ade8030 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -421,6 +421,7 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value); u8 tpm_buf_read_u8(struct tpm_buf *buf, off_t *offset); u16 tpm_buf_read_u16(struct tpm_buf *buf, off_t *offset); u32 tpm_buf_read_u32(struct tpm_buf *buf, off_t *offset); +void tpm_buf_append_handle(struct tpm_chip *chip, struct tpm_buf *buf, u32 handle); /* * Check if TPM device is in the firmware upgrade mode. @@ -505,6 +506,8 @@ void tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf, void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf, u8 attributes, u8 *passphrase, int passphraselen); +void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf, + u8 attributes, u8 *passphrase, int passphraselen); static inline void tpm_buf_append_hmac_session_opt(struct tpm_chip *chip, struct tpm_buf *buf, u8 attributes, -- cgit v1.2.3