[PATCH v2 05/11] tpm: export the context save and load commands

From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: linux-integrity@vger.kernel.org
Cc: Jarkko Sakkinen <jarkko@kernel.org>,
	keyrings@vger.kernel.org, Ard Biesheuvel <ardb@kernel.org>
Subject: [PATCH v2 05/11] tpm: export the context save and load commands
Date: Tue, 24 Jan 2023 12:55:10 -0500	[thread overview]
Message-ID: <20230124175516.5984-6-James.Bottomley@HansenPartnership.com> (raw)
In-Reply-To: <20230124175516.5984-1-James.Bottomley@HansenPartnership.com>

The TPM2 session HMAC and encryption handling code needs to save and
restore a single volatile context for the elliptic curve version of
the NULL seed, so export the APIs which do this for internal use.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
---
 drivers/char/tpm/tpm.h        | 4 ++++
 drivers/char/tpm/tpm2-space.c | 8 ++++----
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 24ee4e1cc452..a5fe37977103 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -237,6 +237,10 @@ int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, void *buf,
 		      size_t *bufsiz);
 int tpm_devs_add(struct tpm_chip *chip);
 void tpm_devs_remove(struct tpm_chip *chip);
+int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
+		      unsigned int buf_size, unsigned int *offset);
+int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
+		      unsigned int *offset, u32 *handle);
 
 void tpm_bios_log_setup(struct tpm_chip *chip);
 void tpm_bios_log_teardown(struct tpm_chip *chip);
diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index ffb35f0154c1..d77ee4af9d65 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -68,8 +68,8 @@ void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space)
 	kfree(space->session_buf);
 }
 
-static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
-			     unsigned int *offset, u32 *handle)
+int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
+		      unsigned int *offset, u32 *handle)
 {
 	struct tpm_buf tbuf;
 	struct tpm2_context *ctx;
@@ -119,8 +119,8 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf,
 	return 0;
 }
 
-static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
-			     unsigned int buf_size, unsigned int *offset)
+int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf,
+		      unsigned int buf_size, unsigned int *offset)
 {
 	struct tpm_buf tbuf;
 	unsigned int body_size;
-- 
2.35.3

