* [PATCH v3 6/7] tpm: Orchestrate TPM commands in tpm_get_random()
From: Jarkko Sakkinen @ 2025-12-10 14:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, David Howells,
Paul Moore, James Morris, Serge E. Hallyn, open list,
open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org>
tpm1_get_random() and tpm2_get_random() contain duplicate orchestration
code. Consolidate orchestration to tpm_get_random().
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm-interface.c | 165 ++++++++++++++++++++++++++++---
drivers/char/tpm/tpm.h | 2 -
drivers/char/tpm/tpm1-cmd.c | 62 ------------
drivers/char/tpm/tpm2-cmd.c | 95 ------------------
4 files changed, 154 insertions(+), 170 deletions(-)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index f745a098908b..ab52a1cb0a78 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -26,7 +26,7 @@
#include <linux/suspend.h>
#include <linux/freezer.h>
#include <linux/tpm_eventlog.h>
-
+#include <linux/tpm_command.h>
#include "tpm.h"
/*
@@ -486,19 +486,143 @@ int tpm_pm_resume(struct device *dev)
}
EXPORT_SYMBOL_GPL(tpm_pm_resume);
+struct tpm1_get_random_out {
+ __be32 rng_data_len;
+ u8 rng_data[TPM_MAX_RNG_DATA];
+} __packed;
+
+static int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max)
+{
+ struct tpm1_get_random_out *resp;
+ u32 recd;
+ int rc;
+
+ if (!out || !max || max > TPM_MAX_RNG_DATA)
+ return -EINVAL;
+
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GETRANDOM);
+ tpm_buf_append_u32(buf, max);
+
+ rc = tpm_transmit_cmd(chip, buf, sizeof(resp->rng_data_len), "TPM_GetRandom");
+ if (rc) {
+ if (rc > 0)
+ rc = -EIO;
+ return rc;
+ }
+
+ resp = (struct tpm1_get_random_out *)&buf->data[TPM_HEADER_SIZE];
+
+ recd = be32_to_cpu(resp->rng_data_len);
+ if (recd > max)
+ return -EIO;
+
+ if (buf->length < TPM_HEADER_SIZE + sizeof(resp->rng_data_len) + recd)
+ return -EIO;
+
+ memcpy(out, resp->rng_data, recd);
+ return recd;
+}
+
+struct tpm2_get_random_out {
+ __be16 size;
+ u8 buffer[TPM_MAX_RNG_DATA];
+} __packed;
+
+static int tpm2_get_random(struct tpm_chip *chip, u8 *out, size_t max)
+{
+ struct tpm2_get_random_out *resp;
+ struct tpm_header *head;
+ off_t offset;
+ u32 recd;
+ int ret;
+
+ if (!out || !max || max > TPM_MAX_RNG_DATA)
+ return -EINVAL;
+
+ struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ tpm_buf_init(buf, TPM_BUFSIZE);
+ tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
+ if (tpm2_chip_auth(chip)) {
+ tpm_buf_append_hmac_session(chip, buf,
+ TPM2_SA_ENCRYPT | TPM2_SA_CONTINUE_SESSION,
+ NULL, 0);
+ } else {
+ head = (struct tpm_header *)buf->data;
+ head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+ }
+ tpm_buf_append_u16(buf, max);
+
+ ret = tpm_buf_fill_hmac_session(chip, buf);
+ if (ret)
+ return ret;
+
+ ret = tpm_transmit_cmd(chip, buf, offsetof(struct tpm2_get_random_out, buffer),
+ "TPM2_GetRandom");
+
+ ret = tpm_buf_check_hmac_response(chip, buf, ret);
+ if (ret) {
+ if (ret > 0)
+ ret = -EIO;
+
+ goto out;
+ }
+
+ head = (struct tpm_header *)buf->data;
+ offset = TPM_HEADER_SIZE;
+
+ /* Skip the parameter size field: */
+ if (be16_to_cpu(head->tag) == TPM2_ST_SESSIONS)
+ offset += 4;
+
+ resp = (struct tpm2_get_random_out *)&buf->data[offset];
+ recd = min_t(u32, be16_to_cpu(resp->size), max);
+
+ if (tpm_buf_length(buf) <
+ TPM_HEADER_SIZE + offsetof(struct tpm2_get_random_out, buffer) + recd) {
+ ret = -EIO;
+ goto out;
+ }
+
+ memcpy(out, resp->buffer, recd);
+ return recd;
+
+out:
+ tpm2_end_auth_session(chip);
+ return ret;
+}
+
/**
- * tpm_get_random() - get random bytes from the TPM's RNG
- * @chip: a &struct tpm_chip instance, %NULL for the default chip
- * @out: destination buffer for the random bytes
- * @max: the max number of bytes to write to @out
+ * tpm_get_random() - Get random bytes from the TPM's RNG
+ * @chip: A &tpm_chip instance. Whenset to %NULL, the default chip is used.
+ * @out: Destination buffer for the acquired random bytes.
+ * @max: The maximum number of bytes to write to @out.
*
- * Return: number of random bytes read or a negative error value.
+ * Iterates pulling more bytes from TPM up until all of the @max bytes have been
+ * received.
+ *
+ * Returns the number of random bytes read on success.
+ * Returns -EINVAL when @out is NULL, or @max is not between zero and
+ * %TPM_MAX_RNG_DATA.
+ * Returns tpm_transmit_cmd() error codes when the TPM command results an
+ * error.
*/
int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
{
+ u32 num_bytes = max;
+ u8 *out_ptr = out;
+ int retries = 5;
+ int total = 0;
int rc;
- if (!out || max > TPM_MAX_RNG_DATA)
+ if (!out || !max || max > TPM_MAX_RNG_DATA)
return -EINVAL;
if (!chip)
@@ -508,11 +632,30 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max)
if (rc)
return rc;
- if (chip->flags & TPM_CHIP_FLAG_TPM2)
- rc = tpm2_get_random(chip, out, max);
- else
- rc = tpm1_get_random(chip, out, max);
+ if (chip->flags & TPM_CHIP_FLAG_TPM2) {
+ rc = tpm2_start_auth_session(chip);
+ if (rc)
+ return rc;
+ }
+
+ do {
+ if (chip->flags & TPM_CHIP_FLAG_TPM2)
+ rc = tpm2_get_random(chip, out_ptr, num_bytes);
+ else
+ rc = tpm1_get_random(chip, out_ptr, num_bytes);
+
+ if (rc < 0)
+ goto err;
+
+ out_ptr += rc;
+ total += rc;
+ num_bytes -= rc;
+ } while (retries-- && total < max);
+
+ tpm_put_ops(chip);
+ return total ? total : -EIO;
+err:
tpm_put_ops(chip);
return rc;
}
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 5395927c62fc..c4bbd8f04605 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -250,7 +250,6 @@ int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf);
ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
const char *desc, size_t min_cap_length);
-int tpm1_get_random(struct tpm_chip *chip, u8 *out, size_t max);
int tpm1_get_pcr_allocation(struct tpm_chip *chip);
unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal);
int tpm_pm_suspend(struct device *dev);
@@ -290,7 +289,6 @@ int tpm2_pcr_read(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digest, u16 *digest_size_ptr);
int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
struct tpm_digest *digests);
-int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max);
ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
u32 *value, const char *desc);
diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
index 11090053ef54..d8f16e66666b 100644
--- a/drivers/char/tpm/tpm1-cmd.c
+++ b/drivers/char/tpm/tpm1-cmd.c
@@ -502,68 +502,6 @@ ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
}
EXPORT_SYMBOL_GPL(tpm1_getcap);
-#define TPM_ORD_GET_RANDOM 70
-struct tpm1_get_random_out {
- __be32 rng_data_len;
- u8 rng_data[TPM_MAX_RNG_DATA];
-} __packed;
-
-/**
- * tpm1_get_random() - get random bytes from the TPM's RNG
- * @chip: a &struct tpm_chip instance
- * @dest: destination buffer for the random bytes
- * @max: the maximum number of bytes to write to @dest
- *
- * Return:
- * * number of bytes read
- * * -errno (positive TPM return codes are masked to -EIO)
- */
-int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
-{
- struct tpm1_get_random_out *out;
- u32 num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
- u32 total = 0;
- int retries = 5;
- u32 recd;
- int rc;
-
- struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
-
- tpm_buf_init(buf, TPM_BUFSIZE);
- do {
- tpm_buf_reset(buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
- tpm_buf_append_u32(buf, num_bytes);
-
- rc = tpm_transmit_cmd(chip, buf, sizeof(out->rng_data_len), "TPM_GetRandom");
- if (rc) {
- if (rc > 0)
- rc = -EIO;
- return rc;
- }
-
- out = (struct tpm1_get_random_out *)&buf->data[TPM_HEADER_SIZE];
-
- recd = be32_to_cpu(out->rng_data_len);
- if (recd > num_bytes)
- return -EFAULT;
-
- if (buf->length < TPM_HEADER_SIZE +
- sizeof(out->rng_data_len) + recd)
- return -EFAULT;
-
- memcpy(dest, out->rng_data, recd);
-
- dest += recd;
- total += recd;
- num_bytes -= recd;
- } while (retries-- && total < max);
-
- rc = total ? (int)total : -EIO;
- return rc;
-}
-
#define TPM_ORD_PCRREAD 21
int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
{
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index bc50d6b734cf..f066efb54a2c 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -233,101 +233,6 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
return rc;
}
-struct tpm2_get_random_out {
- __be16 size;
- u8 buffer[TPM_MAX_RNG_DATA];
-} __packed;
-
-/**
- * tpm2_get_random() - get random bytes from the TPM RNG
- *
- * @chip: a &tpm_chip instance
- * @dest: destination buffer
- * @max: the max number of random bytes to pull
- *
- * Return:
- * size of the buffer on success,
- * -errno otherwise (positive TPM return codes are masked to -EIO)
- */
-int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
-{
- struct tpm2_get_random_out *out;
- struct tpm_header *head;
- u32 recd;
- u32 num_bytes = max;
- int err;
- int total = 0;
- int retries = 5;
- u8 *dest_ptr = dest;
- off_t offset;
-
- if (!num_bytes || max > TPM_MAX_RNG_DATA)
- return -EINVAL;
-
- struct tpm_buf *buf __free(kfree) = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
-
- err = tpm2_start_auth_session(chip);
- if (err)
- return err;
-
- tpm_buf_init(buf, TPM_BUFSIZE);
- do {
- tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_GET_RANDOM);
- if (tpm2_chip_auth(chip)) {
- tpm_buf_append_hmac_session(chip, buf,
- TPM2_SA_ENCRYPT |
- TPM2_SA_CONTINUE_SESSION,
- NULL, 0);
- } else {
- head = (struct tpm_header *)buf->data;
- head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
- }
- tpm_buf_append_u16(buf, num_bytes);
- err = tpm_buf_fill_hmac_session(chip, buf);
- if (err)
- return err;
-
- err = tpm_transmit_cmd(chip, buf,
- offsetof(struct tpm2_get_random_out,
- buffer),
- "TPM2_GetRandom");
- err = tpm_buf_check_hmac_response(chip, buf, err);
- if (err) {
- if (err > 0)
- err = -EIO;
- goto out;
- }
-
- head = (struct tpm_header *)buf->data;
- offset = TPM_HEADER_SIZE;
- /* Skip the parameter size field: */
- if (be16_to_cpu(head->tag) == TPM2_ST_SESSIONS)
- offset += 4;
-
- out = (struct tpm2_get_random_out *)&buf->data[offset];
- recd = min_t(u32, be16_to_cpu(out->size), num_bytes);
- if (tpm_buf_length(buf) <
- TPM_HEADER_SIZE +
- offsetof(struct tpm2_get_random_out, buffer) +
- recd) {
- err = -EFAULT;
- goto out;
- }
- memcpy(dest_ptr, out->buffer, recd);
-
- dest_ptr += recd;
- total += recd;
- num_bytes -= recd;
- } while (retries-- && total < max);
-
- return total ? total : -EIO;
-out:
- tpm2_end_auth_session(chip);
- return err;
-}
-
/**
* tpm2_flush_context() - execute a TPM2_FlushContext command
* @chip: TPM chip to use
--
2.52.0
^ permalink raw reply related
* [PATCH v3 5/7] tpm-buf: Remove tpm_buf_append_handle
From: Jarkko Sakkinen @ 2025-12-10 14:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, David Howells,
Paul Moore, James Morris, Serge E. Hallyn, open list,
open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org>
Since the number of handles is fixed to a single handle, eliminate all uses
of buf->handles and deduce values during compile-time.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
v2:
- Streamline the code change and remove dead code.
---
drivers/char/tpm/tpm-buf.c | 25 -------------------------
drivers/char/tpm/tpm2-cmd.c | 6 ++----
drivers/char/tpm/tpm2-sessions.c | 14 ++------------
include/linux/tpm.h | 2 --
4 files changed, 4 insertions(+), 43 deletions(-)
diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index 73be8a87b472..752c69b8a4f5 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c
@@ -40,7 +40,6 @@ static void __tpm_buf_reset(struct tpm_buf *buf, u16 buf_size, u16 tag, u32 ordi
buf->flags = 0;
buf->length = sizeof(*head);
buf->capacity = buf_size - sizeof(*buf);
- buf->handles = 0;
head->tag = cpu_to_be16(tag);
head->length = cpu_to_be32(sizeof(*head));
head->ordinal = cpu_to_be32(ordinal);
@@ -56,7 +55,6 @@ static void __tpm_buf_reset_sized(struct tpm_buf *buf, u16 buf_size)
buf->flags = TPM_BUF_TPM2B;
buf->length = 2;
buf->capacity = buf_size - sizeof(*buf);
- buf->handles = 0;
buf->data[0] = 0;
buf->data[1] = 0;
}
@@ -177,29 +175,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
}
EXPORT_SYMBOL_GPL(tpm_buf_append_u32);
-/**
- * tpm_buf_append_handle() - Add a handle
- * @buf: &tpm_buf instance
- * @handle: a TPM object handle
- *
- * Add a handle to the buffer, and increase the count tracking the number of
- * handles in the command buffer. Works only for command buffers.
- */
-void tpm_buf_append_handle(struct tpm_buf *buf, u32 handle)
-{
- if (buf->flags & TPM_BUF_INVALID)
- return;
-
- if (buf->flags & TPM_BUF_TPM2B) {
- WARN(1, "tpm-buf: invalid type: TPM2B\n");
- buf->flags |= TPM_BUF_INVALID;
- return;
- }
-
- tpm_buf_append_u32(buf, handle);
- buf->handles++;
-}
-
/**
* tpm_buf_read() - Read from a TPM buffer
* @buf: &tpm_buf instance
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 436ee82620e4..bc50d6b734cf 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -205,7 +205,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
return rc;
tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
} else {
- tpm_buf_append_handle(buf, pcr_idx);
+ tpm_buf_append_u32(buf, pcr_idx);
tpm_buf_append_auth(chip, buf, NULL, 0);
}
@@ -281,10 +281,8 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
TPM2_SA_CONTINUE_SESSION,
NULL, 0);
} else {
- offset = buf->handles * 4 + TPM_HEADER_SIZE;
head = (struct tpm_header *)buf->data;
- if (tpm_buf_length(buf) == offset)
- head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
+ head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
}
tpm_buf_append_u16(buf, num_bytes);
err = tpm_buf_fill_hmac_session(chip, buf);
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 62a200ae72d7..f2b8ca893e15 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -261,7 +261,7 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
if (!tpm2_chip_auth(chip)) {
- tpm_buf_append_handle(buf, handle);
+ tpm_buf_append_u32(buf, handle);
return 0;
}
@@ -288,17 +288,7 @@ EXPORT_SYMBOL_GPL(tpm_buf_append_name);
void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
u8 *passphrase, int passphrase_len)
{
- /* offset tells us where the sessions area begins */
- int offset = buf->handles * 4 + TPM_HEADER_SIZE;
- u32 len = 9 + passphrase_len;
-
- if (tpm_buf_length(buf) != offset) {
- /* not the first session so update the existing length */
- len += get_unaligned_be32(&buf->data[offset]);
- put_unaligned_be32(len, &buf->data[offset]);
- } else {
- tpm_buf_append_u32(buf, len);
- }
+ tpm_buf_append_u32(buf, 9 + passphrase_len);
/* auth handle */
tpm_buf_append_u32(buf, TPM2_RS_PW);
/* nonce */
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 9f684fc7ae04..e68995df8796 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -395,7 +395,6 @@ enum tpm_buf_flags {
*/
struct tpm_buf {
u8 flags;
- u8 handles;
u16 length;
u16 capacity;
u8 data[];
@@ -441,7 +440,6 @@ 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_buf *buf, u32 handle);
/*
* Check if TPM device is in the firmware upgrade mode.
--
2.52.0
^ permalink raw reply related
* [PATCH v3 4/7] tpm2-sessions: Remove AUTH_MAX_NAMES
From: Jarkko Sakkinen @ 2025-12-10 14:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, David Howells,
Paul Moore, James Morris, Serge E. Hallyn, open list,
open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org>
In all of the call sites only one session is ever append. Thus, reduce
AUTH_MAX_NAMES, which leads into removing constant completely.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm2-sessions.c | 31 +++++++++++--------------------
1 file changed, 11 insertions(+), 20 deletions(-)
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 0816a91134fc..62a200ae72d7 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -72,9 +72,6 @@
#include <crypto/sha2.h>
#include <crypto/utils.h>
-/* maximum number of names the TPM must remember for authorization */
-#define AUTH_MAX_NAMES 3
-
#define AES_KEY_BYTES AES_KEYSIZE_128
#define AES_KEY_BITS (AES_KEY_BYTES*8)
@@ -136,8 +133,8 @@ struct tpm2_auth {
* handle, but they are part of the session by name, which
* we must compute and remember
*/
- u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
- u16 name_size_tbl[AUTH_MAX_NAMES];
+ u8 name[TPM2_MAX_NAME_SIZE];
+ u16 name_size;
};
#ifdef CONFIG_TCG_TPM2_HMAC
@@ -254,11 +251,14 @@ EXPORT_SYMBOL_GPL(tpm2_read_public);
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
u32 handle, u8 *name, u16 name_size)
{
-#ifdef CONFIG_TCG_TPM2_HMAC
struct tpm2_auth *auth;
- int slot;
int ret;
-#endif
+
+ if (tpm_buf_length(buf) != TPM_HEADER_SIZE) {
+ dev_err(&chip->dev, "too many handles\n");
+ ret = -EIO;
+ goto err;
+ }
if (!tpm2_chip_auth(chip)) {
tpm_buf_append_handle(buf, handle);
@@ -266,12 +266,6 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
#ifdef CONFIG_TCG_TPM2_HMAC
- slot = (tpm_buf_length(buf) - TPM_HEADER_SIZE) / 4;
- if (slot >= AUTH_MAX_NAMES) {
- dev_err(&chip->dev, "too many handles\n");
- ret = -EIO;
- goto err;
- }
auth = chip->auth;
if (auth->session != tpm_buf_length(buf)) {
dev_err(&chip->dev, "session state malformed");
@@ -280,16 +274,14 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
tpm_buf_append_u32(buf, handle);
auth->session += 4;
- memcpy(auth->name[slot], name, name_size);
- auth->name_size_tbl[slot] = name_size;
+ memcpy(auth->name, name, name_size);
+ auth->name_size = name_size;
#endif
return 0;
-#ifdef CONFIG_TCG_TPM2_HMAC
err:
tpm2_end_auth_session(chip);
return ret;
-#endif
}
EXPORT_SYMBOL_GPL(tpm_buf_append_name);
@@ -658,8 +650,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
/* ordinal is already BE */
sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal));
/* add the handle names */
- for (i = 0; i < handles; i++)
- sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]);
+ sha256_update(&sctx, auth->name, auth->name_size);
if (offset_s != tpm_buf_length(buf))
sha256_update(&sctx, &buf->data[offset_s],
tpm_buf_length(buf) - offset_s);
--
2.52.0
^ permalink raw reply related
* [PATCH v3 3/7] KEYS: trusted: Re-orchestrate tpm2_read_public() calls
From: Jarkko Sakkinen @ 2025-12-10 14:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, David Howells,
Paul Moore, James Morris, Serge E. Hallyn, James Bottomley,
Mimi Zohar, open list, open list:KEYS/KEYRINGS,
open list:SECURITY SUBSYSTEM
In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org>
tpm2_load_cmd() and tpm2_unseal_cmd() use the same parent, and calls to
tpm_buf_append_name() cause the exact same TPM2_ReadPublic command to be
sent to the chip, causing unnecessary traffic.
1. Export tpm2_read_public in order to make it callable from
'trusted_tpm2'.
2. Re-orchestrate tpm2_seal_trusted() and tpm2_unseal_trusted() in order to
halve the name resolutions required:
2a. Move tpm2_read_public() calls into trusted_tpm2.
2b. Pass TPM name to tpm_buf_append_name().
2c. Rework tpm_buf_append_name() to use the pre-resolved name.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm2-cmd.c | 3 +-
drivers/char/tpm/tpm2-sessions.c | 95 +++++------------
include/linux/tpm.h | 10 +-
security/keys/trusted-keys/trusted_tpm2.c | 124 ++++++++++++++--------
4 files changed, 118 insertions(+), 114 deletions(-)
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 543c1c62c938..436ee82620e4 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -199,7 +199,8 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
if (!disable_pcr_integrity) {
- rc = tpm_buf_append_name(chip, buf, pcr_idx, NULL);
+ rc = tpm_buf_append_name(chip, buf, pcr_idx, (u8 *)&pcr_idx,
+ sizeof(u32));
if (rc)
return rc;
tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index a0c88fb1804c..0816a91134fc 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -136,8 +136,8 @@ struct tpm2_auth {
* handle, but they are part of the session by name, which
* we must compute and remember
*/
- u32 name_h[AUTH_MAX_NAMES];
u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
+ u16 name_size_tbl[AUTH_MAX_NAMES];
};
#ifdef CONFIG_TCG_TPM2_HMAC
@@ -163,7 +163,17 @@ static int name_size(const u8 *name)
}
}
-static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
+/**
+ * tpm2_read_public: Resolve TPM name for a handle
+ * @chip: TPM chip to use.
+ * @handle: TPM handle.
+ * @name: A buffer for returning the name blob. Must have a
+ * capacity of 'SHA512_DIGET_SIZE + 2' bytes at minimum
+ *
+ * Returns size of TPM handle name of success.
+ * Returns tpm_transmit_cmd error codes when TPM2_ReadPublic fails.
+ */
+int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
{
u32 mso = tpm2_handle_mso(handle);
off_t offset = TPM_HEADER_SIZE;
@@ -212,14 +222,16 @@ static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
memcpy(name, &buf->data[offset], rc);
return name_size_alg;
}
+EXPORT_SYMBOL_GPL(tpm2_read_public);
#endif /* CONFIG_TCG_TPM2_HMAC */
/**
- * tpm_buf_append_name() - add a handle area to the buffer
- * @chip: the TPM chip structure
- * @buf: The buffer to be appended
- * @handle: The handle to be appended
- * @name: The name of the handle (may be NULL)
+ * tpm_buf_append_name() - Append a handle and store TPM name
+ * @chip: TPM chip to use.
+ * @buf: TPM buffer containing the TPM command in-transit.
+ * @handle: TPM handle to be appended.
+ * @name: TPM name of the handle
+ * @name_size: Size of the TPM name.
*
* In order to compute session HMACs, we need to know the names of the
* objects pointed to by the handles. For most objects, this is simply
@@ -236,15 +248,14 @@ static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
* will be caused by an incorrect programming model and indicated by a
* kernel message.
*
- * Ends the authorization session on failure.
+ * Returns zero on success.
+ * Returns -EIO when the authorization area state is malformed.
*/
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
- u32 handle, u8 *name)
+ u32 handle, u8 *name, u16 name_size)
{
#ifdef CONFIG_TCG_TPM2_HMAC
- enum tpm2_mso_type mso = tpm2_handle_mso(handle);
struct tpm2_auth *auth;
- u16 name_size_alg;
int slot;
int ret;
#endif
@@ -269,36 +280,15 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
tpm_buf_append_u32(buf, handle);
auth->session += 4;
-
- if (mso == TPM2_MSO_PERSISTENT ||
- mso == TPM2_MSO_VOLATILE ||
- mso == TPM2_MSO_NVRAM) {
- if (!name) {
- ret = tpm2_read_public(chip, handle, auth->name[slot]);
- if (ret < 0)
- goto err;
-
- name_size_alg = ret;
- }
- } else {
- if (name) {
- dev_err(&chip->dev, "handle 0x%08x does not use a name\n",
- handle);
- ret = -EIO;
- goto err;
- }
- }
-
- auth->name_h[slot] = handle;
- if (name)
- memcpy(auth->name[slot], name, name_size_alg);
+ memcpy(auth->name[slot], name, name_size);
+ auth->name_size_tbl[slot] = name_size;
#endif
return 0;
#ifdef CONFIG_TCG_TPM2_HMAC
err:
tpm2_end_auth_session(chip);
- return tpm_ret_to_err(ret);
+ return ret;
#endif
}
EXPORT_SYMBOL_GPL(tpm_buf_append_name);
@@ -606,22 +596,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
attrs = chip->cc_attrs_tbl[i];
handles = (attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0);
+ offset_s += handles * sizeof(u32);
- /*
- * just check the names, it's easy to make mistakes. This
- * would happen if someone added a handle via
- * tpm_buf_append_u32() instead of tpm_buf_append_name()
- */
- for (i = 0; i < handles; i++) {
- u32 handle = tpm_buf_read_u32(buf, &offset_s);
-
- if (auth->name_h[i] != handle) {
- dev_err(&chip->dev, "invalid handle 0x%08x\n", handle);
- ret = -EIO;
- goto err;
- }
- }
- /* point offset_s to the start of the sessions */
val = tpm_buf_read_u32(buf, &offset_s);
/* point offset_p to the start of the parameters */
offset_p = offset_s + val;
@@ -682,23 +658,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
/* ordinal is already BE */
sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal));
/* add the handle names */
- for (i = 0; i < handles; i++) {
- enum tpm2_mso_type mso = tpm2_handle_mso(auth->name_h[i]);
-
- if (mso == TPM2_MSO_PERSISTENT ||
- mso == TPM2_MSO_VOLATILE ||
- mso == TPM2_MSO_NVRAM) {
- ret = name_size(auth->name[i]);
- if (ret < 0)
- goto err;
-
- sha256_update(&sctx, auth->name[i], ret);
- } else {
- __be32 h = cpu_to_be32(auth->name_h[i]);
-
- sha256_update(&sctx, (u8 *)&h, 4);
- }
- }
+ for (i = 0; i < handles; i++)
+ sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]);
if (offset_s != tpm_buf_length(buf))
sha256_update(&sctx, &buf->data[offset_s],
tpm_buf_length(buf) - offset_s);
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 922a43ef23b5..9f684fc7ae04 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -543,7 +543,7 @@ static inline struct tpm2_auth *tpm2_chip_auth(struct tpm_chip *chip)
}
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
- u32 handle, u8 *name);
+ u32 handle, u8 *name, u16 name_size);
void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
u8 attributes, u8 *passphrase,
int passphraselen);
@@ -557,6 +557,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf);
int tpm_buf_check_hmac_response(struct tpm_chip *chip, struct tpm_buf *buf,
int rc);
void tpm2_end_auth_session(struct tpm_chip *chip);
+int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name);
#else
#include <linux/unaligned.h>
@@ -580,6 +581,13 @@ static inline int tpm_buf_check_hmac_response(struct tpm_chip *chip,
{
return rc;
}
+
+static inline int tpm2_read_public(struct tpm_chip *chip, u32 handle,
+ void *name)
+{
+ memcpy(name, &handle, sizeof(u32));
+ return sizeof(u32);
+}
#endif /* CONFIG_TCG_TPM2_HMAC */
#endif
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 27424e1a4a63..63539b344ffb 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -203,7 +203,9 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ u8 parent_name[TPM2_MAX_NAME_SIZE];
off_t offset = TPM_HEADER_SIZE;
+ u16 parent_name_size;
int blob_len = 0;
int hash;
u32 flags;
@@ -220,6 +222,12 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
if (rc)
return rc;
+ rc = tpm2_read_public(chip, options->keyhandle, parent_name);
+ if (rc < 0)
+ goto out_put;
+
+ parent_name_size = rc;
+
rc = tpm2_start_auth_session(chip);
if (rc)
goto out_put;
@@ -234,7 +242,8 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
goto out_put;
@@ -326,48 +335,38 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
}
/**
- * tpm2_load_cmd() - execute a TPM2_Load command
- *
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- * @blob_handle: returned blob handle
+ * tpm2_load_cmd() - Execute TPM2_Load
+ * @chip: TPM chip to use.
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
+ * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the
+ * parent key.
+ * @blob: The decoded payload for the key.
+ * @blob_handle: On success, will contain handle to the loaded keyedhash
+ * blob.
*
- * Return: 0 on success.
- * -E2BIG on wrong payload size.
- * -EPERM on tpm error status.
- * < 0 error from tpm_send.
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails.
*/
static int tpm2_load_cmd(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options,
+ u8 *parent_name,
+ u16 parent_name_size,
+ const u8 *blob,
u32 *blob_handle)
{
u8 *blob_ref __free(kfree) = NULL;
unsigned int private_len;
unsigned int public_len;
unsigned int blob_len;
- u8 *blob, *pub;
+ const u8 *pub;
int rc;
u32 attrs;
- rc = tpm2_key_decode(payload, options, &blob);
- if (rc) {
- /* old form */
- blob = payload->blob;
- payload->old_format = 1;
- } else {
- /* Bind for cleanup: */
- blob_ref = blob;
- }
-
- /* new format carries keyhandle but old format doesn't */
- if (!options->keyhandle)
- return -EINVAL;
-
/* must be big enough for at least the two be16 size counts */
if (payload->blob_len < 4)
- return -EINVAL;
+ return -E2BIG;
private_len = get_unaligned_be16(blob);
@@ -406,7 +405,8 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
return rc;
@@ -434,20 +434,23 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
}
/**
- * tpm2_unseal_cmd() - execute a TPM2_Unload command
+ * tpm2_unseal_cmd() - Execute TPM2_Unload
*
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- * @blob_handle: blob handle
+ * @chip: TPM chip to use
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
+ * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the
+ * parent key.
+ * @blob_handle: Handle to the loaded keyedhash blob.
*
- * Return: 0 on success
- * -EPERM on tpm error status
- * < 0 error from tpm_send
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails.
*/
static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options,
+ u8 *parent_name,
+ u16 parent_name_size,
u32 blob_handle)
{
u16 data_len;
@@ -465,7 +468,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
return rc;
@@ -526,30 +530,60 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
}
/**
- * tpm2_unseal_trusted() - unseal the payload of a trusted key
+ * tpm2_unseal_trusted() - Unseal a trusted key
+ * @chip: TPM chip to use.
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
*
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- *
- * Return: Same as with tpm_send.
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Return -EINVAL when parent's key handle has not been set.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load or TPM2_Unseal
+ * fails.
*/
int tpm2_unseal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ u8 *blob_ref __free(kfree) = NULL;
+ u8 parent_name[TPM2_MAX_NAME_SIZE];
+ u16 parent_name_size;
u32 blob_handle;
+ u8 *blob;
int rc;
+ /*
+ * Try to decode the provided blob as an ASN.1 blob. Assume that the
+ * blob is in the legacy format if decoding does not end successfully.
+ */
+ rc = tpm2_key_decode(payload, options, &blob);
+ if (rc) {
+ blob = payload->blob;
+ payload->old_format = 1;
+ } else {
+ blob_ref = blob;
+ }
+
+ if (!options->keyhandle)
+ return -EINVAL;
+
rc = tpm_try_get_ops(chip);
if (rc)
return rc;
- rc = tpm2_load_cmd(chip, payload, options, &blob_handle);
+ rc = tpm2_read_public(chip, options->keyhandle, parent_name);
+ if (rc < 0)
+ goto out;
+
+ parent_name_size = rc;
+
+ rc = tpm2_load_cmd(chip, payload, options, parent_name,
+ parent_name_size, blob, &blob_handle);
if (rc)
goto out;
- rc = tpm2_unseal_cmd(chip, payload, options, blob_handle);
+ rc = tpm2_unseal_cmd(chip, payload, options, parent_name,
+ parent_name_size, blob_handle);
+
tpm2_flush_context(chip, blob_handle);
out:
--
2.52.0
^ permalink raw reply related
* [PATCH v3 2/7] tpm2-sessions: Define TPM2_NAME_MAX_SIZE
From: Jarkko Sakkinen @ 2025-12-10 14:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, David Howells,
Paul Moore, James Morris, Serge E. Hallyn, open list,
open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org>
This is somewhat cosmetic change but it does serve a purpose on tracking
the value set for the maximum length of TPM names, and to clearly states
what components it is composed of. It also anchors the value so that when
buffers are declared for this particular purpose, the same value is used
for the capacity.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
v2:
- Rename TPM2_NAME_SIZE as TPM2_NULL_NAME_SIZE.
---
drivers/char/tpm/tpm-sysfs.c | 2 +-
drivers/char/tpm/tpm2-sessions.c | 2 +-
include/linux/tpm.h | 37 +++++++++++++++++++++-----------
3 files changed, 27 insertions(+), 14 deletions(-)
diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index f5dcadb1ab3c..0f321c307bc6 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -313,7 +313,7 @@ static ssize_t null_name_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct tpm_chip *chip = to_tpm_chip(dev);
- int size = TPM2_NAME_SIZE;
+ int size = TPM2_NULL_NAME_SIZE;
bin2hex(buf, chip->null_key_name, size);
size *= 2;
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 79f27a46bd7f..a0c88fb1804c 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -137,7 +137,7 @@ struct tpm2_auth {
* we must compute and remember
*/
u32 name_h[AUTH_MAX_NAMES];
- u8 name[AUTH_MAX_NAMES][2 + SHA512_DIGEST_SIZE];
+ u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
};
#ifdef CONFIG_TCG_TPM2_HMAC
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 42e2a091f43d..922a43ef23b5 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -28,9 +28,33 @@
#define TPM_DIGEST_SIZE 20 /* Max TPM v1.2 PCR size */
#define TPM_BUFSIZE 4096
+/*
+ * SHA-512 is, as of today, the largest digest in the TCG algorithm repository.
+ */
#define TPM2_MAX_DIGEST_SIZE SHA512_DIGEST_SIZE
+
+/*
+ * A TPM name digest i.e., TPMT_HA, is a concatenation of TPM_ALG_ID of the
+ * name algorithm and hash of TPMT_PUBLIC.
+ */
+#define TPM2_MAX_NAME_SIZE (TPM2_MAX_DIGEST_SIZE + 2)
+
+/*
+ * The maximum number of PCR banks.
+ */
#define TPM2_MAX_PCR_BANKS 8
+/*
+ * fixed define for the size of a name. This is actually HASHALG size
+ * plus 2, so 32 for SHA256
+ */
+#define TPM2_NULL_NAME_SIZE 34
+
+/*
+ * The maximum size for an object context
+ */
+#define TPM2_MAX_CONTEXT_SIZE 4096
+
struct tpm_chip;
struct trusted_key_payload;
struct trusted_key_options;
@@ -140,17 +164,6 @@ struct tpm_chip_seqops {
/* fixed define for the curve we use which is NIST_P256 */
#define EC_PT_SZ 32
-/*
- * fixed define for the size of a name. This is actually HASHALG size
- * plus 2, so 32 for SHA256
- */
-#define TPM2_NAME_SIZE 34
-
-/*
- * The maximum size for an object context
- */
-#define TPM2_MAX_CONTEXT_SIZE 4096
-
struct tpm_chip {
struct device dev;
struct device devs;
@@ -212,7 +225,7 @@ struct tpm_chip {
/* saved context for NULL seed */
u8 null_key_context[TPM2_MAX_CONTEXT_SIZE];
/* name of NULL seed */
- u8 null_key_name[TPM2_NAME_SIZE];
+ u8 null_key_name[TPM2_NULL_NAME_SIZE];
u8 null_ec_key_x[EC_PT_SZ];
u8 null_ec_key_y[EC_PT_SZ];
struct tpm2_auth *auth;
--
2.52.0
^ permalink raw reply related
* [PATCH v3 1/7] KEYS: trusted: Remove dead branch from tpm2_unseal_cmd
From: Jarkko Sakkinen @ 2025-12-10 14:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, David Howells, Paul Moore, James Morris,
Serge E. Hallyn, James Bottomley, Mimi Zohar,
open list:KEYS/KEYRINGS, open list:SECURITY SUBSYSTEM, open list
In-Reply-To: <20251210143940.264191-1-jarkko@kernel.org>
TPM2_Unseal requires TPM2_ST_SESSIONS, and tpm2_unseal_cmd() always does
set up either password or HMAC session.
Remove the branch in tpm2_unseal_cmd() conditionally setting
TPM2_ST_NO_SESSIONS. It is faulty but luckily it is never exercised at
run-time, and thus does not cause regressions.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
security/keys/trusted-keys/trusted_tpm2.c | 10 +---------
1 file changed, 1 insertion(+), 9 deletions(-)
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 9074ae1a5896..27424e1a4a63 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -450,9 +450,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_options *options,
u32 blob_handle)
{
- struct tpm_header *head;
u16 data_len;
- int offset;
u8 *data;
int rc;
@@ -488,14 +486,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
tpm_buf_append_u16(buf, options->blobauth_len);
tpm_buf_append(buf, options->blobauth, options->blobauth_len);
- if (tpm2_chip_auth(chip)) {
+ if (tpm2_chip_auth(chip))
tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT, NULL, 0);
- } else {
- offset = buf->handles * 4 + TPM_HEADER_SIZE;
- head = (struct tpm_header *)buf->data;
- if (tpm_buf_length(buf) == offset)
- head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
- }
}
rc = tpm_buf_fill_hmac_session(chip, buf);
--
2.52.0
^ permalink raw reply related
* [PATCH v3 0/7] Streamline TPM2 HMAC sessions
From: Jarkko Sakkinen @ 2025-12-10 14:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, David Howells, Paul Moore, James Morris,
Serge E. Hallyn, open list:KEYS/KEYRINGS,
open list:SECURITY SUBSYSTEM, open list
Since we cannot at this point cache names of the keys given limitations
of the ASN.1 file format, I'll start a fresh patch set. Let's fixup what
we can right now.
This patch set addresses two major issues in the feature:
1. Dynamic resolution without gain. All kernel sites have at most single
handle to authorize. Even if this changes some day this is how it is
as of today and we definitely do not want to dictate the future but
instead downscale code to the metrics that we have as of today.
2. Eliminate at least one unnnecessary tpm2_read_public() call.
Jarkko Sakkinen (7):
KEYS: trusted: Remove dead branch from tpm2_unseal_cmd
tpm2-sessions: Define TPM2_NAME_MAX_SIZE
KEYS: trusted: Re-orchestrate tpm2_read_public() calls
tpm2-sessions: Remove AUTH_MAX_NAMES
tpm-buf: Remove tpm_buf_append_handle
tpm: Orchestrate TPM commands in tpm_get_random()
tpm: Send only one TPM command per hwrng request
drivers/char/tpm/tpm-buf.c | 25 ----
drivers/char/tpm/tpm-chip.c | 2 +-
drivers/char/tpm/tpm-interface.c | 174 ++++++++++++++++++++--
drivers/char/tpm/tpm-sysfs.c | 2 +-
drivers/char/tpm/tpm.h | 2 -
drivers/char/tpm/tpm1-cmd.c | 62 --------
drivers/char/tpm/tpm2-cmd.c | 102 +------------
drivers/char/tpm/tpm2-sessions.c | 130 +++++-----------
include/linux/tpm.h | 51 +++++--
security/keys/trusted-keys/trusted_tpm1.c | 8 +-
security/keys/trusted-keys/trusted_tpm2.c | 134 ++++++++++-------
11 files changed, 322 insertions(+), 370 deletions(-)
--
2.52.0
^ permalink raw reply
* Re: [PATCH] bpf, arm64: Do not audit capability check in do_jit()
From: patchwork-bot+netdevbpf @ 2025-12-10 7:30 UTC (permalink / raw)
To: Ondrej Mosnacek; +Cc: ast, daniel, bpf, selinux, linux-security-module, serge
In-Reply-To: <20251204125916.441021-1-omosnace@redhat.com>
Hello:
This patch was applied to bpf/bpf.git (master)
by Alexei Starovoitov <ast@kernel.org>:
On Thu, 4 Dec 2025 13:59:16 +0100 you wrote:
> Analogically to the x86 commit 881a9c9cb785 ("bpf: Do not audit
> capability check in do_jit()"), change the capable() call to
> ns_capable_noaudit() in order to avoid spurious SELinux denials in audit
> log.
>
> The commit log from that commit applies here as well:
> """
> The failure of this check only results in a security mitigation being
> applied, slightly affecting performance of the compiled BPF program. It
> doesn't result in a failed syscall, an thus auditing a failed LSM
> permission check for it is unwanted. For example with SELinux, it causes
> a denial to be reported for confined processes running as root, which
> tends to be flagged as a problem to be fixed in the policy. Yet
> dontauditing or allowing CAP_SYS_ADMIN to the domain may not be
> desirable, as it would allow/silence also other checks - either going
> against the principle of least privilege or making debugging potentially
> harder.
>
> [...]
Here is the summary with links:
- bpf, arm64: Do not audit capability check in do_jit()
https://git.kernel.org/bpf/bpf/c/189e5deb944a
You are awesome, thank you!
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^ permalink raw reply
* An opinion about Linux security
From: Timur Chernykh @ 2025-12-10 0:15 UTC (permalink / raw)
To: torvalds; +Cc: linux-security-module
Hello Linus,
I’m writing to ask for your opinion. What do you think about Linux’s
current readiness for security-focused commercial products? I’m
particularly interested in several areas.
First, in today’s 3rd-party (out-of-tree) EDR development — EDR being
the most common commercial class of security products — eBPF has
effectively become the main option. Yet eBPF is extremely restrictive.
It is not possible to write fully expressive real-time analysis code:
the verifier is overly strict, non-deterministic loops are not
allowed, and older kernels lack BTF support. These issues create real
limitations.
Second, the removal of the out-of-tree LSM API in the 4.x kernel
series caused significant problems for many AV/EDR vendors. I was
unable to find an explanation in the mailing lists that convincingly
justified that decision.
The next closest mechanism, fanotify, was a genuine improvement.
However, it does not allow an AV/EDR vendor to protect the integrity
of its own product. Is Linux truly expecting modern AV/EDR solutions
to rely on fanotify alone?
My main question is: what are the future plans? Linux provides very
few APIs for security and dynamic analysis. eBPF is still immature,
fanotify is insufficient, and driver workarounds that bypass kernel
restrictions are risky — they introduce both stability and security
problems. At the same time, properly implemented in-tree LSMs are not
inherently dangerous and remain the safer, supported path for
extending security functionality. Without safe, supported interfaces,
however, commercial products struggle to be competitive. At the
moment, macOS with its Endpoint Security Framework is significantly
ahead.
Yes, the kernel includes multiple in-tree LSM modules, but in practice
SELinux does not simplify operations — it often complicates them,
despite its long-standing presence. Many of the other LSMs are rarely
used in production. As an EDR developer, I seldom encounter them, and
when I do, they usually provide little practical value. Across
numerous real-world server intrusions, none of these LSM modules have
meaningfully prevented attacks, despite many years of kernel
development.
Perhaps it is time for Linux to focus on more than a theoretical model
of security.
P.S.
Everything above reflects only my personal opinion. I would greatly
appreciate your response and any criticism you may have.
Best regards,
Timur Chernykh
^ permalink raw reply
* Re: [f2fs-dev] [PATCH kvm-next V11 0/7] Add NUMA mempolicy support for KVM guest-memfd
From: patchwork-bot+f2fs @ 2025-12-09 17:18 UTC (permalink / raw)
To: Garg, Shivank
Cc: willy, akpm, david, pbonzini, shuah, seanjc, vbabka, jgowans,
mhocko, jack, kvm, dhavale, linux-btrfs, aik, papaluri, kalyazin,
peterx, linux-mm, clm, ddutile, linux-kselftest, shdhiman, gshan,
ying.huang, ira.weiny, roypat, matthew.brost, linux-coco,
zbestahu, lorenzo.stoakes, linux-bcachefs, apopple, jmorris, hch,
chao.gao, cgzones, ziy, rientjes, yuzhao, xiang, nikunj, gourry,
serge, thomas.lendacky, ashish.kalra, chao.p.peng, yan.y.zhao,
byungchul, michael.day, Neeraj.Upadhyay, michael.roth, bfoster,
bharata, josef, Liam.Howlett, ackerleytng, dsterba, viro,
jefflexu, jaegeuk, dan.j.williams, surenb, tabba, paul,
joshua.hahnjy, brauner, quic_eberman, rakie.kim, pvorel,
linux-erofs, kent.overstreet, linux-kernel, linux-f2fs-devel,
pankaj.gupta, linux-security-module, lihongbo22, amit,
linux-fsdevel, vannapurve, suzuki.poulose, rppt, jgg
In-Reply-To: <20250827175247.83322-2-shivankg@amd.com>
Hello:
This series was applied to jaegeuk/f2fs.git (dev)
by Sean Christopherson <seanjc@google.com>:
On Wed, 27 Aug 2025 17:52:41 +0000 you wrote:
> This series introduces NUMA-aware memory placement support for KVM guests
> with guest_memfd memory backends. It builds upon Fuad Tabba's work (V17)
> that enabled host-mapping for guest_memfd memory [1] and can be applied
> directly applied on KVM tree [2] (branch kvm-next, base commit: a6ad5413,
> Merge branch 'guest-memfd-mmap' into HEAD)
>
> == Background ==
> KVM's guest-memfd memory backend currently lacks support for NUMA policy
> enforcement, causing guest memory allocations to be distributed across host
> nodes according to kernel's default behavior, irrespective of any policy
> specified by the VMM. This limitation arises because conventional userspace
> NUMA control mechanisms like mbind(2) don't work since the memory isn't
> directly mapped to userspace when allocations occur.
> Fuad's work [1] provides the necessary mmap capability, and this series
> leverages it to enable mbind(2).
>
> [...]
Here is the summary with links:
- [f2fs-dev,kvm-next,V11,1/7] mm/filemap: Add NUMA mempolicy support to filemap_alloc_folio()
(no matching commit)
- [f2fs-dev,kvm-next,V11,2/7] mm/filemap: Extend __filemap_get_folio() to support NUMA memory policies
https://git.kernel.org/jaegeuk/f2fs/c/16a542e22339
- [f2fs-dev,kvm-next,V11,3/7] mm/mempolicy: Export memory policy symbols
https://git.kernel.org/jaegeuk/f2fs/c/f634f10809ec
- [f2fs-dev,kvm-next,V11,4/7] KVM: guest_memfd: Use guest mem inodes instead of anonymous inodes
(no matching commit)
- [f2fs-dev,kvm-next,V11,5/7] KVM: guest_memfd: Add slab-allocated inode cache
(no matching commit)
- [f2fs-dev,kvm-next,V11,6/7] KVM: guest_memfd: Enforce NUMA mempolicy using shared policy
(no matching commit)
- [f2fs-dev,kvm-next,V11,7/7] KVM: guest_memfd: selftests: Add tests for mmap and NUMA policy support
(no matching commit)
You are awesome, thank you!
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^ permalink raw reply
* Re: Are setuid shell scripts safe? (Implied by security_bprm_creds_for_exec)
From: Jan Kara @ 2025-12-09 12:28 UTC (permalink / raw)
To: Bernd Edlinger
Cc: Al Viro, Eric W. Biederman, Roberto Sassu, Alexey Dobriyan,
Oleg Nesterov, Kees Cook, Andy Lutomirski, Will Drewry,
Christian Brauner, Andrew Morton, Michal Hocko, Serge Hallyn,
James Morris, Randy Dunlap, Suren Baghdasaryan, Yafang Shao,
Helge Deller, Adrian Reber, Thomas Gleixner, Jens Axboe,
Alexei Starovoitov, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-kselftest, linux-mm,
linux-security-module, tiozhang, Luis Chamberlain,
Paulo Alcantara (SUSE), Sergey Senozhatsky, Frederic Weisbecker,
YueHaibing, Paul Moore, Aleksa Sarai, Stefan Roesch, Chao Yu,
xu xin, Jeff Layton, Jan Kara, David Hildenbrand, Dave Chinner,
Shuah Khan, Elena Reshetova, David Windsor, Mateusz Guzik,
Ard Biesheuvel, Joel Fernandes (Google), Matthew Wilcox (Oracle),
Hans Liljestrand, Penglei Jiang, Lorenzo Stoakes, Adrian Ratiu,
Ingo Molnar, Peter Zijlstra (Intel), Cyrill Gorcunov,
Eric Dumazet, zohar, linux-integrity, Ryan Lee, apparmor
In-Reply-To: <GV2PPF74270EBEE0AAAE2EB22B668EE21A7E4A6A@GV2PPF74270EBEE.EURP195.PROD.OUTLOOK.COM>
On Thu 04-12-25 14:03:27, Bernd Edlinger wrote:
> On 12/4/25 06:49, Al Viro wrote:
> > On Wed, Dec 03, 2025 at 02:16:29PM +0100, Bernd Edlinger wrote:
> >
> >> Hmm, yes, that looks like an issue.
> >>
> >> I would have expected the security engine to look at bprm->filenanme
> >> especially in the case, when bprm->interp != bprm->filename,
> >> and check that it is not a sym-link with write-access for the
> >> current user and of course also that the bprm->file is not a regular file
> >> which is writable by the current user, if that is the case I would have expected
> >> the secuity engine to enforce non-new-privs on a SUID executable somehow.
> >
> > Check that _what_ is not a symlink? And while we are at it, what do write
> > permissions to any symlinks have to do with anything whatsoever?
>
> When we execve a normal executable, we do open the binary file with
> deny_write_access so this might allow the security engine to inspaect the
> binary, before it is used.
That would be seriously flawed IMO because there are lot of cases where
code is executed without deny_write_access() - like shared libraries, code
loaded by interpreter, and probably more.
> However this behavior has changed recently,
> now it has some exceptions, where even this behavior is no longer
> guaranteed for binary executables, due to commit
> 0357ef03c94ef835bd44a0658b8edb672a9dbf51, but why? I have no idea...
Because for hierarchical storage implementation you may need to fill in the
executable data from remote storage on demand and the deny_write_access
logic was making this impossible. We even tried to completely remove the
deny_write_access logic exactly because it has very limited use and
complicates things (commit 2a010c412853 ("fs: don't block i_writecount
during exec")) but that had to be reverted because some userspace depends
on the ETXTBUSY behavior.
Honza
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
^ permalink raw reply
* [RFC][PATCH] ima: Add support for staging measurements for deletion
From: Roberto Sassu @ 2025-12-09 10:17 UTC (permalink / raw)
To: corbet, zohar, dmitry.kasatkin, eric.snowberg, paul, jmorris,
serge
Cc: linux-doc, linux-kernel, linux-integrity, linux-security-module,
gregorylumen, chenste, nramas, Roberto Sassu
From: Roberto Sassu <roberto.sassu@huawei.com>
Introduce the ability of staging the entire of the IMA measurement list, or
a portion, for deletion. Staging means moving the current content of the
measurement list to a separate location, and allowing users to read and
delete it. This causes the measurement list to be atomically truncated
before new measurements can be added. Staging can be done only once at a
time.
User space is responsible to concatenate the staged IMA measurements list
portions following the temporal order in which the operations were done,
together with the current measurement list. Then, it can send the collected
data to the remote verifiers.
The benefit of this solution is the ability to free precious kernel memory,
in exchange of delegating user space to reconstruct the full measurement
list from the chunks. No trust needs to be given to user space, since the
integrity of the measurement list is protected by the TPM.
By default, staging the measurements list for deletion does not alter the
hash table. When staging is done, IMA is still able to detect collisions on
the staged and later deleted measurement entries, by keeping the entry
digests (only template data are freed).
However, since during the measurements list serialization only the SHA1
digest is passed, and since there are no template data to recalculate the
other digests from, the hash table is currently not populated with digests
from staged/deleted entries after kexec().
Introduce the new kernel option ima_flush_htable to decide whether or not
the digests of staged measurement entries are flushed from the hash table.
Then, introduce ascii_runtime_measurements_staged_<algo> and
binary_runtime_measurement_staged_<algo> interfaces to stage/delete the
measurements. Use 'echo A > <IMA interface>' and 'echo D > <IMA interface>'
to respectively stage and delete the entire measurements list. Use
'echo N > <IMA interface>', with N between 1 and ULONG_MAX, to stage the
selected portion of the measurements list.
The ima_measure_users counter (protected by the ima_measure_lock mutex) has
been introduced to protect access to the measurement list and the staged
part. The open method of all the measurement interfaces has been extended
to allow only one writer at a time or, in alternative, multiple readers.
The write permission is used to stage/delete the measurements, the read
permission to read them. Write requires also the CAP_SYS_ADMIN capability.
Finally, introduce the _notrim version of the run-time measurements count
and the binary measurements list size, to display them in the kexec-related
critical data records.
Note: This code derives from the Alt-IMA Huawei project, and is being
released under the dual license model (GPL-2.0 OR MIT).
Link: https://github.com/linux-integrity/linux/issues/1
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
.../admin-guide/kernel-parameters.txt | 4 +
security/integrity/ima/ima.h | 10 +-
security/integrity/ima/ima_fs.c | 222 +++++++++++++++++-
security/integrity/ima/ima_kexec.c | 13 +-
security/integrity/ima/ima_queue.c | 111 ++++++++-
5 files changed, 340 insertions(+), 20 deletions(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 6c42061ca20e..355d8930e3ac 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2215,6 +2215,10 @@
Use the canonical format for the binary runtime
measurements, instead of host native format.
+ ima_flush_htable [IMA]
+ Flush the measurement list hash table when staging all
+ or a part of it for deletion.
+
ima_hash= [IMA]
Format: { md5 | sha1 | rmd160 | sha256 | sha384
| sha512 | ... }
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index e3d71d8d56e3..d7aa4a0f79b1 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -117,6 +117,8 @@ struct ima_queue_entry {
struct ima_template_entry *entry;
};
extern struct list_head ima_measurements; /* list of all measurements */
+extern struct list_head ima_measurements_staged; /* list of staged meas. */
+extern bool ima_measurements_staged_exist; /* If there are staged meas. */
/* Some details preceding the binary serialized measurement list */
struct ima_kexec_hdr {
@@ -281,10 +283,12 @@ struct ima_template_desc *ima_template_desc_current(void);
struct ima_template_desc *ima_template_desc_buf(void);
struct ima_template_desc *lookup_template_desc(const char *name);
bool ima_template_has_modsig(const struct ima_template_desc *ima_template);
+int ima_queue_stage(unsigned long req_value);
+int ima_queue_delete_staged(void);
int ima_restore_measurement_entry(struct ima_template_entry *entry);
int ima_restore_measurement_list(loff_t bufsize, void *buf);
int ima_measurements_show(struct seq_file *m, void *v);
-unsigned long ima_get_binary_runtime_size(void);
+unsigned long ima_get_binary_runtime_size(bool notrim);
int ima_init_template(void);
void ima_init_template_list(void);
int __init ima_init_digests(void);
@@ -298,11 +302,13 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
extern spinlock_t ima_queue_lock;
struct ima_h_table {
- atomic_long_t len; /* number of stored measurements in the list */
+ atomic_long_t len; /* current num of stored meas. in the list */
+ atomic_long_t len_notrim; /* total num of stored meas. in the list */
atomic_long_t violations;
struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
};
extern struct ima_h_table ima_htable;
+extern struct mutex ima_extend_list_mutex;
static inline unsigned int ima_hash_key(u8 *digest)
{
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index 87045b09f120..321c98ae0e55 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -24,7 +24,12 @@
#include "ima.h"
+/* Requests: ('A', [1, ULONG_MAX])\n (stage all/N) or D\n (delete staged) */
+#define STAGED_REQ_LENGTH 21
+
static DEFINE_MUTEX(ima_write_mutex);
+static DEFINE_MUTEX(ima_measure_lock);
+static long ima_measure_users;
bool ima_canonical_fmt;
static int __init default_canonical_fmt_setup(char *str)
@@ -74,14 +79,15 @@ static const struct file_operations ima_measurements_count_ops = {
};
/* returns pointer to hlist_node */
-static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
+static void *_ima_measurements_start(struct seq_file *m, loff_t *pos,
+ struct list_head *head)
{
loff_t l = *pos;
struct ima_queue_entry *qe;
/* we need a lock since pos could point beyond last element */
rcu_read_lock();
- list_for_each_entry_rcu(qe, &ima_measurements, later) {
+ list_for_each_entry_rcu(qe, head, later) {
if (!l--) {
rcu_read_unlock();
return qe;
@@ -91,7 +97,18 @@ static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
return NULL;
}
-static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos)
+static void *ima_measurements_start(struct seq_file *m, loff_t *pos)
+{
+ return _ima_measurements_start(m, pos, &ima_measurements);
+}
+
+static void *ima_measurements_staged_start(struct seq_file *m, loff_t *pos)
+{
+ return _ima_measurements_start(m, pos, &ima_measurements_staged);
+}
+
+static void *_ima_measurements_next(struct seq_file *m, void *v, loff_t *pos,
+ struct list_head *head)
{
struct ima_queue_entry *qe = v;
@@ -103,7 +120,18 @@ static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos)
rcu_read_unlock();
(*pos)++;
- return (&qe->later == &ima_measurements) ? NULL : qe;
+ return (&qe->later == head) ? NULL : qe;
+}
+
+static void *ima_measurements_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ return _ima_measurements_next(m, v, pos, &ima_measurements);
+}
+
+static void *ima_measurements_staged_next(struct seq_file *m, void *v,
+ loff_t *pos)
+{
+ return _ima_measurements_next(m, v, pos, &ima_measurements_staged);
}
static void ima_measurements_stop(struct seq_file *m, void *v)
@@ -202,16 +230,138 @@ static const struct seq_operations ima_measurments_seqops = {
.show = ima_measurements_show
};
+static int _ima_measurements_open(struct inode *inode, struct file *file,
+ const struct seq_operations *seq_ops)
+{
+ bool write = !!(file->f_mode & FMODE_WRITE);
+ int ret;
+
+ if (write && !capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ mutex_lock(&ima_measure_lock);
+ if ((write && ima_measure_users != 0) ||
+ (!write && ima_measure_users < 0)) {
+ mutex_unlock(&ima_measure_lock);
+ return -EBUSY;
+ }
+
+ ret = seq_open(file, seq_ops);
+ if (ret < 0) {
+ mutex_unlock(&ima_measure_lock);
+ return ret;
+ }
+
+ if (write)
+ ima_measure_users--;
+ else
+ ima_measure_users++;
+
+ mutex_unlock(&ima_measure_lock);
+ return ret;
+}
+
static int ima_measurements_open(struct inode *inode, struct file *file)
{
- return seq_open(file, &ima_measurments_seqops);
+ return _ima_measurements_open(inode, file, &ima_measurments_seqops);
+}
+
+static int ima_measurements_release(struct inode *inode, struct file *file)
+{
+ bool write = !!(file->f_mode & FMODE_WRITE);
+ int ret;
+
+ mutex_lock(&ima_measure_lock);
+ ret = seq_release(inode, file);
+ if (!ret) {
+ if (write)
+ ima_measure_users++;
+ else
+ ima_measure_users--;
+ }
+
+ mutex_unlock(&ima_measure_lock);
+ return ret;
}
static const struct file_operations ima_measurements_ops = {
.open = ima_measurements_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = seq_release,
+ .release = ima_measurements_release,
+};
+
+static const struct seq_operations ima_measurments_staged_seqops = {
+ .start = ima_measurements_staged_start,
+ .next = ima_measurements_staged_next,
+ .stop = ima_measurements_stop,
+ .show = ima_measurements_show
+};
+
+static int ima_measurements_staged_open(struct inode *inode, struct file *file)
+{
+ return _ima_measurements_open(inode, file,
+ &ima_measurments_staged_seqops);
+}
+
+static ssize_t ima_measurements_staged_read(struct file *file, char __user *buf,
+ size_t size, loff_t *ppos)
+{
+ if (!ima_measurements_staged_exist)
+ return -ENOENT;
+
+ return seq_read(file, buf, size, ppos);
+}
+
+static ssize_t ima_measurements_staged_write(struct file *file,
+ const char __user *buf,
+ size_t datalen, loff_t *ppos)
+{
+ char req[STAGED_REQ_LENGTH], *req_ptr = req;
+ unsigned long req_value;
+ int ret;
+
+ if (*ppos > 0 || datalen < 2 || datalen > STAGED_REQ_LENGTH)
+ return -EINVAL;
+
+ ret = copy_from_user(req, buf, datalen);
+ if (ret < 0)
+ return ret;
+
+ if (strsep(&req_ptr, "\n") == NULL)
+ return -EINVAL;
+
+ switch (req[0]) {
+ case 'A':
+ if (datalen != 2 || req[1] != '\0')
+ return -EINVAL;
+
+ ret = ima_queue_stage(ULONG_MAX);
+ break;
+ case 'D':
+ if (datalen != 2 || req[1] != '\0')
+ return -EINVAL;
+
+ ret = ima_queue_delete_staged();
+ break;
+ default:
+ ret = kstrtoul(req, 0, &req_value);
+ if (!ret)
+ ret = ima_queue_stage(req_value);
+ }
+
+ if (ret < 0)
+ return ret;
+
+ return datalen;
+}
+
+static const struct file_operations ima_measurements_staged_ops = {
+ .open = ima_measurements_staged_open,
+ .read = ima_measurements_staged_read,
+ .write = ima_measurements_staged_write,
+ .llseek = seq_lseek,
+ .release = ima_measurements_release,
};
void ima_print_digest(struct seq_file *m, u8 *digest, u32 size)
@@ -279,14 +429,37 @@ static const struct seq_operations ima_ascii_measurements_seqops = {
static int ima_ascii_measurements_open(struct inode *inode, struct file *file)
{
- return seq_open(file, &ima_ascii_measurements_seqops);
+ return _ima_measurements_open(inode, file,
+ &ima_ascii_measurements_seqops);
}
static const struct file_operations ima_ascii_measurements_ops = {
.open = ima_ascii_measurements_open,
.read = seq_read,
.llseek = seq_lseek,
- .release = seq_release,
+ .release = ima_measurements_release,
+};
+
+static const struct seq_operations ima_ascii_measurements_staged_seqops = {
+ .start = ima_measurements_staged_start,
+ .next = ima_measurements_staged_next,
+ .stop = ima_measurements_stop,
+ .show = ima_ascii_measurements_show
+};
+
+static int ima_ascii_measurements_staged_open(struct inode *inode,
+ struct file *file)
+{
+ return _ima_measurements_open(inode, file,
+ &ima_ascii_measurements_staged_seqops);
+}
+
+static const struct file_operations ima_ascii_measurements_staged_ops = {
+ .open = ima_ascii_measurements_staged_open,
+ .read = ima_measurements_staged_read,
+ .write = ima_measurements_staged_write,
+ .llseek = seq_lseek,
+ .release = ima_measurements_release,
};
static ssize_t ima_read_policy(char *path)
@@ -419,6 +592,25 @@ static int __init create_securityfs_measurement_lists(void)
&ima_measurements_ops);
if (IS_ERR(dentry))
return PTR_ERR(dentry);
+
+ sprintf(file_name, "ascii_runtime_measurements_staged_%s",
+ hash_algo_name[algo]);
+ dentry = securityfs_create_file(file_name,
+ S_IRUSR | S_IRGRP | S_IWUSR | S_IWGRP,
+ ima_dir, (void *)(uintptr_t)i,
+ &ima_ascii_measurements_staged_ops);
+ if (IS_ERR(dentry))
+ return PTR_ERR(dentry);
+
+ sprintf(file_name, "binary_runtime_measurements_staged_%s",
+ hash_algo_name[algo]);
+ dentry = securityfs_create_file(file_name,
+ S_IRUSR | S_IRGRP |
+ S_IWUSR | S_IWGRP,
+ ima_dir, (void *)(uintptr_t)i,
+ &ima_measurements_staged_ops);
+ if (IS_ERR(dentry))
+ return PTR_ERR(dentry);
}
return 0;
@@ -528,6 +720,20 @@ int __init ima_fs_init(void)
goto out;
}
+ dentry = securityfs_create_symlink("binary_runtime_measurements_staged",
+ ima_dir, "binary_runtime_measurements_staged_sha1", NULL);
+ if (IS_ERR(dentry)) {
+ ret = PTR_ERR(dentry);
+ goto out;
+ }
+
+ dentry = securityfs_create_symlink("ascii_runtime_measurements_staged",
+ ima_dir, "ascii_runtime_measurements_staged_sha1", NULL);
+ if (IS_ERR(dentry)) {
+ ret = PTR_ERR(dentry);
+ goto out;
+ }
+
dentry = securityfs_create_file("runtime_measurements_count",
S_IRUSR | S_IRGRP, ima_dir, NULL,
&ima_measurements_count_ops);
diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
index 7362f68f2d8b..23a20300da7b 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -40,8 +40,8 @@ void ima_measure_kexec_event(const char *event_name)
long len;
int n;
- buf_size = ima_get_binary_runtime_size();
- len = atomic_long_read(&ima_htable.len);
+ buf_size = ima_get_binary_runtime_size(true);
+ len = atomic_long_read(&ima_htable.len_notrim);
n = scnprintf(ima_kexec_event, IMA_KEXEC_EVENT_LEN,
"kexec_segment_size=%lu;ima_binary_runtime_size=%lu;"
@@ -93,8 +93,10 @@ static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer,
memset(&khdr, 0, sizeof(khdr));
khdr.version = 1;
- /* This is an append-only list, no need to hold the RCU read lock */
- list_for_each_entry_rcu(qe, &ima_measurements, later, true) {
+
+ /* It can race with ima_queue_stage(). */
+ mutex_lock(&ima_extend_list_mutex);
+ list_for_each_entry(qe, &ima_measurements, later) {
if (ima_kexec_file.count < ima_kexec_file.size) {
khdr.count++;
ima_measurements_show(&ima_kexec_file, qe);
@@ -103,6 +105,7 @@ static int ima_dump_measurement_list(unsigned long *buffer_size, void **buffer,
break;
}
}
+ mutex_unlock(&ima_extend_list_mutex);
/*
* fill in reserved space with some buffer details
@@ -157,7 +160,7 @@ void ima_add_kexec_buffer(struct kimage *image)
else
extra_memory = CONFIG_IMA_KEXEC_EXTRA_MEMORY_KB * 1024;
- binary_runtime_size = ima_get_binary_runtime_size() + extra_memory;
+ binary_runtime_size = ima_get_binary_runtime_size(false) + extra_memory;
if (binary_runtime_size >= ULONG_MAX - PAGE_SIZE)
kexec_segment_size = ULONG_MAX;
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index 590637e81ad1..868f216ac343 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c
@@ -22,19 +22,32 @@
#define AUDIT_CAUSE_LEN_MAX 32
+bool ima_flush_htable;
+static int __init ima_flush_htable_setup(char *str)
+{
+ ima_flush_htable = true;
+ return 1;
+}
+__setup("ima_flush_htable", ima_flush_htable_setup);
+
/* pre-allocated array of tpm_digest structures to extend a PCR */
static struct tpm_digest *digests;
LIST_HEAD(ima_measurements); /* list of all measurements */
+LIST_HEAD(ima_measurements_staged); /* list of staged measurements */
+bool ima_measurements_staged_exist; /* If there are staged measurements */
#ifdef CONFIG_IMA_KEXEC
static unsigned long binary_runtime_size;
+static unsigned long binary_runtime_size_notrim;
#else
static unsigned long binary_runtime_size = ULONG_MAX;
+static unsigned long binary_runtime_size_notrim = ULONG_MAX;
#endif
/* key: inode (before secure-hashing a file) */
struct ima_h_table ima_htable = {
.len = ATOMIC_LONG_INIT(0),
+ .len_notrim = ATOMIC_LONG_INIT(0),
.violations = ATOMIC_LONG_INIT(0),
.queue[0 ... IMA_MEASURE_HTABLE_SIZE - 1] = HLIST_HEAD_INIT
};
@@ -43,7 +56,7 @@ struct ima_h_table ima_htable = {
* and extending the TPM PCR aggregate. Since tpm_extend can take
* long (and the tpm driver uses a mutex), we can't use the spinlock.
*/
-static DEFINE_MUTEX(ima_extend_list_mutex);
+DEFINE_MUTEX(ima_extend_list_mutex);
/*
* Used internally by the kernel to suspend measurements.
@@ -114,15 +127,19 @@ static int ima_add_digest_entry(struct ima_template_entry *entry,
list_add_tail_rcu(&qe->later, &ima_measurements);
atomic_long_inc(&ima_htable.len);
+ atomic_long_inc(&ima_htable.len_notrim);
if (update_htable) {
key = ima_hash_key(entry->digests[ima_hash_algo_idx].digest);
hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);
}
- if (binary_runtime_size != ULONG_MAX) {
+ if (binary_runtime_size_notrim != ULONG_MAX) {
int size;
size = get_binary_runtime_size(entry);
+ binary_runtime_size_notrim =
+ (binary_runtime_size_notrim < ULONG_MAX - size) ?
+ binary_runtime_size_notrim + size : ULONG_MAX;
binary_runtime_size = (binary_runtime_size < ULONG_MAX - size) ?
binary_runtime_size + size : ULONG_MAX;
}
@@ -134,12 +151,18 @@ static int ima_add_digest_entry(struct ima_template_entry *entry,
* entire binary_runtime_measurement list, including the ima_kexec_hdr
* structure.
*/
-unsigned long ima_get_binary_runtime_size(void)
+unsigned long ima_get_binary_runtime_size(bool notrim)
{
- if (binary_runtime_size >= (ULONG_MAX - sizeof(struct ima_kexec_hdr)))
+ unsigned long *val;
+
+ mutex_lock(&ima_extend_list_mutex);
+ val = (notrim) ? &binary_runtime_size_notrim : &binary_runtime_size;
+ mutex_unlock(&ima_extend_list_mutex);
+
+ if (*val >= (ULONG_MAX - sizeof(struct ima_kexec_hdr)))
return ULONG_MAX;
else
- return binary_runtime_size + sizeof(struct ima_kexec_hdr);
+ return *val + sizeof(struct ima_kexec_hdr);
}
static int ima_pcr_extend(struct tpm_digest *digests_arg, int pcr)
@@ -220,6 +243,84 @@ int ima_add_template_entry(struct ima_template_entry *entry, int violation,
return result;
}
+int ima_queue_stage(unsigned long req_value)
+{
+ unsigned long req_value_copy = req_value, to_remove = 0;
+ struct ima_queue_entry *qe;
+
+ if (ima_measurements_staged_exist)
+ return -EEXIST;
+
+ mutex_lock(&ima_extend_list_mutex);
+ if (list_empty(&ima_measurements)) {
+ mutex_unlock(&ima_extend_list_mutex);
+ return -ENOENT;
+ }
+
+ if (req_value == ULONG_MAX) {
+ list_replace(&ima_measurements, &ima_measurements_staged);
+ INIT_LIST_HEAD(&ima_measurements);
+ atomic_long_set(&ima_htable.len, 0);
+ if (IS_ENABLED(CONFIG_IMA_KEXEC))
+ binary_runtime_size = 0;
+ } else {
+ list_for_each_entry(qe, &ima_measurements, later) {
+ to_remove += get_binary_runtime_size(qe->entry);
+ if (--req_value_copy == 0)
+ break;
+ }
+
+ if (req_value_copy > 0) {
+ mutex_unlock(&ima_extend_list_mutex);
+ return -ENOENT;
+ }
+
+ __list_cut_position(&ima_measurements_staged, &ima_measurements,
+ &qe->later);
+ atomic_long_sub(req_value, &ima_htable.len);
+ if (IS_ENABLED(CONFIG_IMA_KEXEC))
+ binary_runtime_size -= to_remove;
+ }
+
+ if (ima_flush_htable) {
+ list_for_each_entry(qe, &ima_measurements_staged, later)
+ /* It can race with ima_lookup_digest_entry(). */
+ hlist_del_rcu(&qe->hnext);
+ }
+
+ mutex_unlock(&ima_extend_list_mutex);
+ ima_measurements_staged_exist = true;
+ return 0;
+}
+
+int ima_queue_delete_staged(void)
+{
+ struct ima_queue_entry *qe, *qe_tmp;
+ unsigned int i;
+
+ if (!ima_measurements_staged_exist)
+ return -ENOENT;
+
+ list_for_each_entry_safe(qe, qe_tmp, &ima_measurements_staged, later) {
+ for (i = 0; i < qe->entry->template_desc->num_fields; i++) {
+ kfree(qe->entry->template_data[i].data);
+ qe->entry->template_data[i].data = NULL;
+ qe->entry->template_data[i].len = 0;
+ }
+
+ list_del(&qe->later);
+
+ if (ima_flush_htable) {
+ kfree(qe->entry->digests);
+ kfree(qe->entry);
+ kfree(qe);
+ }
+ }
+
+ ima_measurements_staged_exist = false;
+ return 0;
+}
+
int ima_restore_measurement_entry(struct ima_template_entry *entry)
{
int result = 0;
--
2.43.0
^ permalink raw reply related
* [PATCH v2 3/5] KEYS: trusted: Re-orchestrate tpm2_read_public() calls
From: Jarkko Sakkinen @ 2025-12-09 10:05 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, James Bottomley,
Mimi Zohar, David Howells, Paul Moore, James Morris,
Serge E. Hallyn, open list, open list:KEYS-TRUSTED,
open list:SECURITY SUBSYSTEM
In-Reply-To: <20251209100529.1700779-1-jarkko@kernel.org>
tpm2_load_cmd() and tpm2_unseal_cmd() use the same parent, and calls to
tpm_buf_append_name() cause the exact same TPM2_ReadPublic command to be
sent to the chip, causing unnecessary traffic.
1. Export tpm2_read_public in order to make it callable from
'trusted_tpm2'.
2. Re-orchestrate tpm2_seal_trusted() and tpm2_unseal_trusted() in order to
halve the name resolutions required:
2a. Move tpm2_read_public() calls into trusted_tpm2.
2b. Pass TPM name to tpm_buf_append_name().
2c. Rework tpm_buf_append_name() to use the pre-resolved name.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm2-cmd.c | 3 +-
drivers/char/tpm/tpm2-sessions.c | 95 +++++------------
include/linux/tpm.h | 10 +-
security/keys/trusted-keys/trusted_tpm2.c | 124 ++++++++++++++--------
4 files changed, 118 insertions(+), 114 deletions(-)
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 2682f5ec09cb..5b04e74b6377 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -199,7 +199,8 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
if (!disable_pcr_integrity) {
- rc = tpm_buf_append_name(chip, buf, pcr_idx, NULL);
+ rc = tpm_buf_append_name(chip, buf, pcr_idx, (u8 *)&pcr_idx,
+ sizeof(u32));
if (rc)
return rc;
tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index a0c88fb1804c..0816a91134fc 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -136,8 +136,8 @@ struct tpm2_auth {
* handle, but they are part of the session by name, which
* we must compute and remember
*/
- u32 name_h[AUTH_MAX_NAMES];
u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
+ u16 name_size_tbl[AUTH_MAX_NAMES];
};
#ifdef CONFIG_TCG_TPM2_HMAC
@@ -163,7 +163,17 @@ static int name_size(const u8 *name)
}
}
-static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
+/**
+ * tpm2_read_public: Resolve TPM name for a handle
+ * @chip: TPM chip to use.
+ * @handle: TPM handle.
+ * @name: A buffer for returning the name blob. Must have a
+ * capacity of 'SHA512_DIGET_SIZE + 2' bytes at minimum
+ *
+ * Returns size of TPM handle name of success.
+ * Returns tpm_transmit_cmd error codes when TPM2_ReadPublic fails.
+ */
+int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
{
u32 mso = tpm2_handle_mso(handle);
off_t offset = TPM_HEADER_SIZE;
@@ -212,14 +222,16 @@ static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
memcpy(name, &buf->data[offset], rc);
return name_size_alg;
}
+EXPORT_SYMBOL_GPL(tpm2_read_public);
#endif /* CONFIG_TCG_TPM2_HMAC */
/**
- * tpm_buf_append_name() - add a handle area to the buffer
- * @chip: the TPM chip structure
- * @buf: The buffer to be appended
- * @handle: The handle to be appended
- * @name: The name of the handle (may be NULL)
+ * tpm_buf_append_name() - Append a handle and store TPM name
+ * @chip: TPM chip to use.
+ * @buf: TPM buffer containing the TPM command in-transit.
+ * @handle: TPM handle to be appended.
+ * @name: TPM name of the handle
+ * @name_size: Size of the TPM name.
*
* In order to compute session HMACs, we need to know the names of the
* objects pointed to by the handles. For most objects, this is simply
@@ -236,15 +248,14 @@ static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
* will be caused by an incorrect programming model and indicated by a
* kernel message.
*
- * Ends the authorization session on failure.
+ * Returns zero on success.
+ * Returns -EIO when the authorization area state is malformed.
*/
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
- u32 handle, u8 *name)
+ u32 handle, u8 *name, u16 name_size)
{
#ifdef CONFIG_TCG_TPM2_HMAC
- enum tpm2_mso_type mso = tpm2_handle_mso(handle);
struct tpm2_auth *auth;
- u16 name_size_alg;
int slot;
int ret;
#endif
@@ -269,36 +280,15 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
tpm_buf_append_u32(buf, handle);
auth->session += 4;
-
- if (mso == TPM2_MSO_PERSISTENT ||
- mso == TPM2_MSO_VOLATILE ||
- mso == TPM2_MSO_NVRAM) {
- if (!name) {
- ret = tpm2_read_public(chip, handle, auth->name[slot]);
- if (ret < 0)
- goto err;
-
- name_size_alg = ret;
- }
- } else {
- if (name) {
- dev_err(&chip->dev, "handle 0x%08x does not use a name\n",
- handle);
- ret = -EIO;
- goto err;
- }
- }
-
- auth->name_h[slot] = handle;
- if (name)
- memcpy(auth->name[slot], name, name_size_alg);
+ memcpy(auth->name[slot], name, name_size);
+ auth->name_size_tbl[slot] = name_size;
#endif
return 0;
#ifdef CONFIG_TCG_TPM2_HMAC
err:
tpm2_end_auth_session(chip);
- return tpm_ret_to_err(ret);
+ return ret;
#endif
}
EXPORT_SYMBOL_GPL(tpm_buf_append_name);
@@ -606,22 +596,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
attrs = chip->cc_attrs_tbl[i];
handles = (attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0);
+ offset_s += handles * sizeof(u32);
- /*
- * just check the names, it's easy to make mistakes. This
- * would happen if someone added a handle via
- * tpm_buf_append_u32() instead of tpm_buf_append_name()
- */
- for (i = 0; i < handles; i++) {
- u32 handle = tpm_buf_read_u32(buf, &offset_s);
-
- if (auth->name_h[i] != handle) {
- dev_err(&chip->dev, "invalid handle 0x%08x\n", handle);
- ret = -EIO;
- goto err;
- }
- }
- /* point offset_s to the start of the sessions */
val = tpm_buf_read_u32(buf, &offset_s);
/* point offset_p to the start of the parameters */
offset_p = offset_s + val;
@@ -682,23 +658,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
/* ordinal is already BE */
sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal));
/* add the handle names */
- for (i = 0; i < handles; i++) {
- enum tpm2_mso_type mso = tpm2_handle_mso(auth->name_h[i]);
-
- if (mso == TPM2_MSO_PERSISTENT ||
- mso == TPM2_MSO_VOLATILE ||
- mso == TPM2_MSO_NVRAM) {
- ret = name_size(auth->name[i]);
- if (ret < 0)
- goto err;
-
- sha256_update(&sctx, auth->name[i], ret);
- } else {
- __be32 h = cpu_to_be32(auth->name_h[i]);
-
- sha256_update(&sctx, (u8 *)&h, 4);
- }
- }
+ for (i = 0; i < handles; i++)
+ sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]);
if (offset_s != tpm_buf_length(buf))
sha256_update(&sctx, &buf->data[offset_s],
tpm_buf_length(buf) - offset_s);
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 922a43ef23b5..9f684fc7ae04 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -543,7 +543,7 @@ static inline struct tpm2_auth *tpm2_chip_auth(struct tpm_chip *chip)
}
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
- u32 handle, u8 *name);
+ u32 handle, u8 *name, u16 name_size);
void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
u8 attributes, u8 *passphrase,
int passphraselen);
@@ -557,6 +557,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf);
int tpm_buf_check_hmac_response(struct tpm_chip *chip, struct tpm_buf *buf,
int rc);
void tpm2_end_auth_session(struct tpm_chip *chip);
+int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name);
#else
#include <linux/unaligned.h>
@@ -580,6 +581,13 @@ static inline int tpm_buf_check_hmac_response(struct tpm_chip *chip,
{
return rc;
}
+
+static inline int tpm2_read_public(struct tpm_chip *chip, u32 handle,
+ void *name)
+{
+ memcpy(name, &handle, sizeof(u32));
+ return sizeof(u32);
+}
#endif /* CONFIG_TCG_TPM2_HMAC */
#endif
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 27424e1a4a63..63539b344ffb 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -203,7 +203,9 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ u8 parent_name[TPM2_MAX_NAME_SIZE];
off_t offset = TPM_HEADER_SIZE;
+ u16 parent_name_size;
int blob_len = 0;
int hash;
u32 flags;
@@ -220,6 +222,12 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
if (rc)
return rc;
+ rc = tpm2_read_public(chip, options->keyhandle, parent_name);
+ if (rc < 0)
+ goto out_put;
+
+ parent_name_size = rc;
+
rc = tpm2_start_auth_session(chip);
if (rc)
goto out_put;
@@ -234,7 +242,8 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
goto out_put;
@@ -326,48 +335,38 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
}
/**
- * tpm2_load_cmd() - execute a TPM2_Load command
- *
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- * @blob_handle: returned blob handle
+ * tpm2_load_cmd() - Execute TPM2_Load
+ * @chip: TPM chip to use.
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
+ * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the
+ * parent key.
+ * @blob: The decoded payload for the key.
+ * @blob_handle: On success, will contain handle to the loaded keyedhash
+ * blob.
*
- * Return: 0 on success.
- * -E2BIG on wrong payload size.
- * -EPERM on tpm error status.
- * < 0 error from tpm_send.
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails.
*/
static int tpm2_load_cmd(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options,
+ u8 *parent_name,
+ u16 parent_name_size,
+ const u8 *blob,
u32 *blob_handle)
{
u8 *blob_ref __free(kfree) = NULL;
unsigned int private_len;
unsigned int public_len;
unsigned int blob_len;
- u8 *blob, *pub;
+ const u8 *pub;
int rc;
u32 attrs;
- rc = tpm2_key_decode(payload, options, &blob);
- if (rc) {
- /* old form */
- blob = payload->blob;
- payload->old_format = 1;
- } else {
- /* Bind for cleanup: */
- blob_ref = blob;
- }
-
- /* new format carries keyhandle but old format doesn't */
- if (!options->keyhandle)
- return -EINVAL;
-
/* must be big enough for at least the two be16 size counts */
if (payload->blob_len < 4)
- return -EINVAL;
+ return -E2BIG;
private_len = get_unaligned_be16(blob);
@@ -406,7 +405,8 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
return rc;
@@ -434,20 +434,23 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
}
/**
- * tpm2_unseal_cmd() - execute a TPM2_Unload command
+ * tpm2_unseal_cmd() - Execute TPM2_Unload
*
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- * @blob_handle: blob handle
+ * @chip: TPM chip to use
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
+ * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the
+ * parent key.
+ * @blob_handle: Handle to the loaded keyedhash blob.
*
- * Return: 0 on success
- * -EPERM on tpm error status
- * < 0 error from tpm_send
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails.
*/
static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options,
+ u8 *parent_name,
+ u16 parent_name_size,
u32 blob_handle)
{
u16 data_len;
@@ -465,7 +468,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
return rc;
@@ -526,30 +530,60 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
}
/**
- * tpm2_unseal_trusted() - unseal the payload of a trusted key
+ * tpm2_unseal_trusted() - Unseal a trusted key
+ * @chip: TPM chip to use.
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
*
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- *
- * Return: Same as with tpm_send.
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Return -EINVAL when parent's key handle has not been set.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load or TPM2_Unseal
+ * fails.
*/
int tpm2_unseal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ u8 *blob_ref __free(kfree) = NULL;
+ u8 parent_name[TPM2_MAX_NAME_SIZE];
+ u16 parent_name_size;
u32 blob_handle;
+ u8 *blob;
int rc;
+ /*
+ * Try to decode the provided blob as an ASN.1 blob. Assume that the
+ * blob is in the legacy format if decoding does not end successfully.
+ */
+ rc = tpm2_key_decode(payload, options, &blob);
+ if (rc) {
+ blob = payload->blob;
+ payload->old_format = 1;
+ } else {
+ blob_ref = blob;
+ }
+
+ if (!options->keyhandle)
+ return -EINVAL;
+
rc = tpm_try_get_ops(chip);
if (rc)
return rc;
- rc = tpm2_load_cmd(chip, payload, options, &blob_handle);
+ rc = tpm2_read_public(chip, options->keyhandle, parent_name);
+ if (rc < 0)
+ goto out;
+
+ parent_name_size = rc;
+
+ rc = tpm2_load_cmd(chip, payload, options, parent_name,
+ parent_name_size, blob, &blob_handle);
if (rc)
goto out;
- rc = tpm2_unseal_cmd(chip, payload, options, blob_handle);
+ rc = tpm2_unseal_cmd(chip, payload, options, parent_name,
+ parent_name_size, blob_handle);
+
tpm2_flush_context(chip, blob_handle);
out:
--
2.52.0
^ permalink raw reply related
* [PATCH v2 1/5] KEYS: trusted: Remove dead branch from tpm2_unseal_cmd
From: Jarkko Sakkinen @ 2025-12-09 10:05 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, James Bottomley,
Mimi Zohar, David Howells, Paul Moore, James Morris,
Serge E. Hallyn, open list, open list:KEYS-TRUSTED,
open list:SECURITY SUBSYSTEM
In-Reply-To: <20251209100529.1700779-1-jarkko@kernel.org>
TPM2_Unseal requires TPM2_ST_SESSIONS, and tpm2_unseal_cmd() always does
set up either password or HMAC session.
Remove the branch in tpm2_unseal_cmd() conditionally setting
TPM2_ST_NO_SESSIONS. It is faulty but luckily it is never exercised at
run-time, and thus does not cause regressions.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
security/keys/trusted-keys/trusted_tpm2.c | 10 +---------
1 file changed, 1 insertion(+), 9 deletions(-)
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 9074ae1a5896..27424e1a4a63 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -450,9 +450,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_options *options,
u32 blob_handle)
{
- struct tpm_header *head;
u16 data_len;
- int offset;
u8 *data;
int rc;
@@ -488,14 +486,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
tpm_buf_append_u16(buf, options->blobauth_len);
tpm_buf_append(buf, options->blobauth, options->blobauth_len);
- if (tpm2_chip_auth(chip)) {
+ if (tpm2_chip_auth(chip))
tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT, NULL, 0);
- } else {
- offset = buf->handles * 4 + TPM_HEADER_SIZE;
- head = (struct tpm_header *)buf->data;
- if (tpm_buf_length(buf) == offset)
- head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
- }
}
rc = tpm_buf_fill_hmac_session(chip, buf);
--
2.52.0
^ permalink raw reply related
* Re: [PATCH 1/1] IMA event log trimming
From: Roberto Sassu @ 2025-12-09 9:36 UTC (permalink / raw)
To: James Bottomley, steven chen, linux-integrity
Cc: zohar, roberto.sassu, dmitry.kasatkin, eric.snowberg, paul,
jmorris, serge, linux-security-module, anirudhve, gregorylumen,
nramas, sushring
In-Reply-To: <d0c00469a8501483baffaf1158102c0f2c5211e8.camel@HansenPartnership.com>
On Tue, 2025-12-09 at 07:17 +0900, James Bottomley wrote:
> On Mon, 2025-12-08 at 10:40 +0100, Roberto Sassu wrote:
> > I have the impression that none the functionality you cited has to be
> > implemented in the kernel, because the only component one can trust
> > to verify the integrity of the IMA measurements list is the TPM.
> > Whether either the kernel or user space retain the measurements is
> > irrelevant.
>
> That's correct, I'm not advocating moving quoting into the kernel. Co-
> ordinating the trim with where the quote gets you to is phenomenally
> useful. While you could theoretically store any mismatch in userspace,
> having two locations for the log makes it more error prone.
>
> > I believe that the only role of the kernel is to get rid of the
> > measurements entries as fast as possible (the kernel would act more
> > like a buffer).
>
> I wouldn't say that, I'd say to get rid of measurements that the user
> has indicated are of no further use.
Different users could have different and conflicting requirements, and
we would spend time trying to conciliate those. We can avoid that by
doing it the same for everyone, and the additional cost of handling it
I believe it is fair.
I could accept staging N entries since I already agreed with Gregory
and Steven, and since it requires only an extra iteration in the linked
list. The other desired functionality should be implemented in user
space.
> > This was actually the intent of my original proposal in
> > https://github.com/linux-integrity/linux/issues/1 . The idea of
> > staging (was snapshotting, but Mimi thinks the term is not accurate)
> > is simply to detach the entire IMA measurement list as fast as
> > possible. Further read and delete after staging is done without
> > interfering with new measurements (sure, the detaching of the hash
> > table is not yet as efficient as I hoped).
>
> From the application point of view, offloading the log and random
> points is a bit more work because now the log collector has to be
> modified to look in multiple locations and we'd also need an agreement
> of where those locations are and how the log is sequenced in a naming
> scheme so it's the same for every distribution. If the application is
> in charge of trimming the log at a particular point, collection remains
> the same (it can simply be the existing in-kernel location), so we
> don't need a cross distro agreement, and the trim can simply be added
> as an extra function.
It could be a single location, the user space program would be
responsible to present the IMA measurement list as if it was never
trimmed.
Roberto
^ permalink raw reply
* Re: [PATCH 4/4] tpm-buf: Remove tpm_buf_append_handle
From: Jarkko Sakkinen @ 2025-12-09 7:52 UTC (permalink / raw)
To: linux-integrity
Cc: Peter Huewe, Jason Gunthorpe, James Bottomley, Mimi Zohar,
David Howells, Paul Moore, James Morris, Serge E. Hallyn,
open list, open list:KEYS-TRUSTED, open list:SECURITY SUBSYSTEM
In-Reply-To: <20251209073903.767518-5-jarkko@kernel.org>
On Tue, Dec 09, 2025 at 09:39:02AM +0200, Jarkko Sakkinen wrote:
> Since the number of handles is fixed to a single handle, eliminate all uses
> of buf->handles and deduce values during compile-time.
>
> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
> ---
> drivers/char/tpm/tpm-buf.c | 25 -----------------------
> drivers/char/tpm/tpm2-cmd.c | 4 ++--
> drivers/char/tpm/tpm2-sessions.c | 4 ++--
> include/linux/tpm.h | 1 -
> security/keys/trusted-keys/trusted_tpm2.c | 2 +-
> 5 files changed, 5 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
> index 73be8a87b472..752c69b8a4f5 100644
> --- a/drivers/char/tpm/tpm-buf.c
> +++ b/drivers/char/tpm/tpm-buf.c
> @@ -40,7 +40,6 @@ static void __tpm_buf_reset(struct tpm_buf *buf, u16 buf_size, u16 tag, u32 ordi
> buf->flags = 0;
> buf->length = sizeof(*head);
> buf->capacity = buf_size - sizeof(*buf);
> - buf->handles = 0;
> head->tag = cpu_to_be16(tag);
> head->length = cpu_to_be32(sizeof(*head));
> head->ordinal = cpu_to_be32(ordinal);
> @@ -56,7 +55,6 @@ static void __tpm_buf_reset_sized(struct tpm_buf *buf, u16 buf_size)
> buf->flags = TPM_BUF_TPM2B;
> buf->length = 2;
> buf->capacity = buf_size - sizeof(*buf);
> - buf->handles = 0;
> buf->data[0] = 0;
> buf->data[1] = 0;
> }
> @@ -177,29 +175,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
> }
> EXPORT_SYMBOL_GPL(tpm_buf_append_u32);
>
> -/**
> - * tpm_buf_append_handle() - Add a handle
> - * @buf: &tpm_buf instance
> - * @handle: a TPM object handle
> - *
> - * Add a handle to the buffer, and increase the count tracking the number of
> - * handles in the command buffer. Works only for command buffers.
> - */
> -void tpm_buf_append_handle(struct tpm_buf *buf, u32 handle)
> -{
> - if (buf->flags & TPM_BUF_INVALID)
> - return;
> -
> - if (buf->flags & TPM_BUF_TPM2B) {
> - WARN(1, "tpm-buf: invalid type: TPM2B\n");
> - buf->flags |= TPM_BUF_INVALID;
> - return;
> - }
> -
> - tpm_buf_append_u32(buf, handle);
> - buf->handles++;
> -}
> -
> /**
> * tpm_buf_read() - Read from a TPM buffer
> * @buf: &tpm_buf instance
> diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
> index 5b04e74b6377..d14e249831c7 100644
> --- a/drivers/char/tpm/tpm2-cmd.c
> +++ b/drivers/char/tpm/tpm2-cmd.c
> @@ -205,7 +205,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
> return rc;
> tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
> } else {
> - tpm_buf_append_handle(buf, pcr_idx);
> + tpm_buf_append_u32(buf, pcr_idx);
> tpm_buf_append_auth(chip, buf, NULL, 0);
> }
>
> @@ -281,7 +281,7 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
> TPM2_SA_CONTINUE_SESSION,
> NULL, 0);
> } else {
> - offset = buf->handles * 4 + TPM_HEADER_SIZE;
> + offset = TPM_HEADER_SIZE + sizeof(u32);
> head = (struct tpm_header *)buf->data;
> if (tpm_buf_length(buf) == offset)
> head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
> index 62a200ae72d7..dfd1abe673bc 100644
> --- a/drivers/char/tpm/tpm2-sessions.c
> +++ b/drivers/char/tpm/tpm2-sessions.c
> @@ -261,7 +261,7 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
> }
>
> if (!tpm2_chip_auth(chip)) {
> - tpm_buf_append_handle(buf, handle);
> + tpm_buf_append_u32(buf, handle);
> return 0;
> }
>
> @@ -289,7 +289,7 @@ void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
> u8 *passphrase, int passphrase_len)
> {
> /* offset tells us where the sessions area begins */
> - int offset = buf->handles * 4 + TPM_HEADER_SIZE;
> + int offset = TPM_HEADER_SIZE + sizeof(u32);
> u32 len = 9 + passphrase_len;
>
> if (tpm_buf_length(buf) != offset) {
> diff --git a/include/linux/tpm.h b/include/linux/tpm.h
> index db716841973f..e20647cc0a0f 100644
> --- a/include/linux/tpm.h
> +++ b/include/linux/tpm.h
> @@ -437,7 +437,6 @@ 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_buf *buf, u32 handle);
>
> /*
> * Check if TPM device is in the firmware upgrade mode.
> diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
> index 7756aa839d81..0a07a18da2ed 100644
> --- a/security/keys/trusted-keys/trusted_tpm2.c
> +++ b/security/keys/trusted-keys/trusted_tpm2.c
> @@ -495,7 +495,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
> if (tpm2_chip_auth(chip)) {
> tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT, NULL, 0);
> } else {
> - offset = buf->handles * 4 + TPM_HEADER_SIZE;
> + offset = TPM_HEADER_SIZE + sizeof(u32);
Maybe it would be sensible to define:
/*
* Offset of the authorization area of a TPM command with a single
* handle.
*/
#define TPM2_AUTH_OFFSET (TPM_HEADER_SIZE + sizeof(u32))
This would overall clarify how this code works.
> head = (struct tpm_header *)buf->data;
> if (tpm_buf_length(buf) == offset)
> head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> --
> 2.52.0
>
BR, Jarkko
^ permalink raw reply
* [PATCH 4/4] tpm-buf: Remove tpm_buf_append_handle
From: Jarkko Sakkinen @ 2025-12-09 7:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, James Bottomley,
Mimi Zohar, David Howells, Paul Moore, James Morris,
Serge E. Hallyn, open list, open list:KEYS-TRUSTED,
open list:SECURITY SUBSYSTEM
In-Reply-To: <20251209073903.767518-1-jarkko@kernel.org>
Since the number of handles is fixed to a single handle, eliminate all uses
of buf->handles and deduce values during compile-time.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm-buf.c | 25 -----------------------
drivers/char/tpm/tpm2-cmd.c | 4 ++--
drivers/char/tpm/tpm2-sessions.c | 4 ++--
include/linux/tpm.h | 1 -
security/keys/trusted-keys/trusted_tpm2.c | 2 +-
5 files changed, 5 insertions(+), 31 deletions(-)
diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index 73be8a87b472..752c69b8a4f5 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c
@@ -40,7 +40,6 @@ static void __tpm_buf_reset(struct tpm_buf *buf, u16 buf_size, u16 tag, u32 ordi
buf->flags = 0;
buf->length = sizeof(*head);
buf->capacity = buf_size - sizeof(*buf);
- buf->handles = 0;
head->tag = cpu_to_be16(tag);
head->length = cpu_to_be32(sizeof(*head));
head->ordinal = cpu_to_be32(ordinal);
@@ -56,7 +55,6 @@ static void __tpm_buf_reset_sized(struct tpm_buf *buf, u16 buf_size)
buf->flags = TPM_BUF_TPM2B;
buf->length = 2;
buf->capacity = buf_size - sizeof(*buf);
- buf->handles = 0;
buf->data[0] = 0;
buf->data[1] = 0;
}
@@ -177,29 +175,6 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
}
EXPORT_SYMBOL_GPL(tpm_buf_append_u32);
-/**
- * tpm_buf_append_handle() - Add a handle
- * @buf: &tpm_buf instance
- * @handle: a TPM object handle
- *
- * Add a handle to the buffer, and increase the count tracking the number of
- * handles in the command buffer. Works only for command buffers.
- */
-void tpm_buf_append_handle(struct tpm_buf *buf, u32 handle)
-{
- if (buf->flags & TPM_BUF_INVALID)
- return;
-
- if (buf->flags & TPM_BUF_TPM2B) {
- WARN(1, "tpm-buf: invalid type: TPM2B\n");
- buf->flags |= TPM_BUF_INVALID;
- return;
- }
-
- tpm_buf_append_u32(buf, handle);
- buf->handles++;
-}
-
/**
* tpm_buf_read() - Read from a TPM buffer
* @buf: &tpm_buf instance
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 5b04e74b6377..d14e249831c7 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -205,7 +205,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
return rc;
tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
} else {
- tpm_buf_append_handle(buf, pcr_idx);
+ tpm_buf_append_u32(buf, pcr_idx);
tpm_buf_append_auth(chip, buf, NULL, 0);
}
@@ -281,7 +281,7 @@ int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
TPM2_SA_CONTINUE_SESSION,
NULL, 0);
} else {
- offset = buf->handles * 4 + TPM_HEADER_SIZE;
+ offset = TPM_HEADER_SIZE + sizeof(u32);
head = (struct tpm_header *)buf->data;
if (tpm_buf_length(buf) == offset)
head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index 62a200ae72d7..dfd1abe673bc 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -261,7 +261,7 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
if (!tpm2_chip_auth(chip)) {
- tpm_buf_append_handle(buf, handle);
+ tpm_buf_append_u32(buf, handle);
return 0;
}
@@ -289,7 +289,7 @@ void tpm_buf_append_auth(struct tpm_chip *chip, struct tpm_buf *buf,
u8 *passphrase, int passphrase_len)
{
/* offset tells us where the sessions area begins */
- int offset = buf->handles * 4 + TPM_HEADER_SIZE;
+ int offset = TPM_HEADER_SIZE + sizeof(u32);
u32 len = 9 + passphrase_len;
if (tpm_buf_length(buf) != offset) {
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index db716841973f..e20647cc0a0f 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -437,7 +437,6 @@ 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_buf *buf, u32 handle);
/*
* Check if TPM device is in the firmware upgrade mode.
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 7756aa839d81..0a07a18da2ed 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -495,7 +495,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
if (tpm2_chip_auth(chip)) {
tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT, NULL, 0);
} else {
- offset = buf->handles * 4 + TPM_HEADER_SIZE;
+ offset = TPM_HEADER_SIZE + sizeof(u32);
head = (struct tpm_header *)buf->data;
if (tpm_buf_length(buf) == offset)
head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
--
2.52.0
^ permalink raw reply related
* [PATCH 2/4] KEYS: trusted: Re-orchestrate tpm2_read_public() calls
From: Jarkko Sakkinen @ 2025-12-09 7:39 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, Peter Huewe, Jason Gunthorpe, James Bottomley,
Mimi Zohar, David Howells, Paul Moore, James Morris,
Serge E. Hallyn, open list, open list:KEYS-TRUSTED,
open list:SECURITY SUBSYSTEM
In-Reply-To: <20251209073903.767518-1-jarkko@kernel.org>
tpm2_load_cmd() and tpm2_unseal_cmd() use the same parent, and calls to
tpm_buf_append_name() cause the exact same TPM2_ReadPublic command to be
sent to the chip, causing unnecessary traffic.
1. Export tpm2_read_public in order to make it callable from
'trusted_tpm2'.
2. Re-orchestrate tpm2_seal_trusted() and tpm2_unseal_trusted() in order to
halve the name resolutions required:
2a. Move tpm2_read_public() calls into trusted_tpm2.
2b. Pass TPM name to tpm_buf_append_name().
2c. Rework tpm_buf_append_name() to use the pre-resolved name.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
drivers/char/tpm/tpm2-cmd.c | 3 +-
drivers/char/tpm/tpm2-sessions.c | 95 +++++------------
include/linux/tpm.h | 10 +-
security/keys/trusted-keys/trusted_tpm2.c | 124 ++++++++++++++--------
4 files changed, 118 insertions(+), 114 deletions(-)
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 2682f5ec09cb..5b04e74b6377 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -199,7 +199,8 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND);
if (!disable_pcr_integrity) {
- rc = tpm_buf_append_name(chip, buf, pcr_idx, NULL);
+ rc = tpm_buf_append_name(chip, buf, pcr_idx, (u8 *)&pcr_idx,
+ sizeof(u32));
if (rc)
return rc;
tpm_buf_append_hmac_session(chip, buf, 0, NULL, 0);
diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessions.c
index a0c88fb1804c..0816a91134fc 100644
--- a/drivers/char/tpm/tpm2-sessions.c
+++ b/drivers/char/tpm/tpm2-sessions.c
@@ -136,8 +136,8 @@ struct tpm2_auth {
* handle, but they are part of the session by name, which
* we must compute and remember
*/
- u32 name_h[AUTH_MAX_NAMES];
u8 name[AUTH_MAX_NAMES][TPM2_MAX_NAME_SIZE];
+ u16 name_size_tbl[AUTH_MAX_NAMES];
};
#ifdef CONFIG_TCG_TPM2_HMAC
@@ -163,7 +163,17 @@ static int name_size(const u8 *name)
}
}
-static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
+/**
+ * tpm2_read_public: Resolve TPM name for a handle
+ * @chip: TPM chip to use.
+ * @handle: TPM handle.
+ * @name: A buffer for returning the name blob. Must have a
+ * capacity of 'SHA512_DIGET_SIZE + 2' bytes at minimum
+ *
+ * Returns size of TPM handle name of success.
+ * Returns tpm_transmit_cmd error codes when TPM2_ReadPublic fails.
+ */
+int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
{
u32 mso = tpm2_handle_mso(handle);
off_t offset = TPM_HEADER_SIZE;
@@ -212,14 +222,16 @@ static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
memcpy(name, &buf->data[offset], rc);
return name_size_alg;
}
+EXPORT_SYMBOL_GPL(tpm2_read_public);
#endif /* CONFIG_TCG_TPM2_HMAC */
/**
- * tpm_buf_append_name() - add a handle area to the buffer
- * @chip: the TPM chip structure
- * @buf: The buffer to be appended
- * @handle: The handle to be appended
- * @name: The name of the handle (may be NULL)
+ * tpm_buf_append_name() - Append a handle and store TPM name
+ * @chip: TPM chip to use.
+ * @buf: TPM buffer containing the TPM command in-transit.
+ * @handle: TPM handle to be appended.
+ * @name: TPM name of the handle
+ * @name_size: Size of the TPM name.
*
* In order to compute session HMACs, we need to know the names of the
* objects pointed to by the handles. For most objects, this is simply
@@ -236,15 +248,14 @@ static int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name)
* will be caused by an incorrect programming model and indicated by a
* kernel message.
*
- * Ends the authorization session on failure.
+ * Returns zero on success.
+ * Returns -EIO when the authorization area state is malformed.
*/
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
- u32 handle, u8 *name)
+ u32 handle, u8 *name, u16 name_size)
{
#ifdef CONFIG_TCG_TPM2_HMAC
- enum tpm2_mso_type mso = tpm2_handle_mso(handle);
struct tpm2_auth *auth;
- u16 name_size_alg;
int slot;
int ret;
#endif
@@ -269,36 +280,15 @@ int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
}
tpm_buf_append_u32(buf, handle);
auth->session += 4;
-
- if (mso == TPM2_MSO_PERSISTENT ||
- mso == TPM2_MSO_VOLATILE ||
- mso == TPM2_MSO_NVRAM) {
- if (!name) {
- ret = tpm2_read_public(chip, handle, auth->name[slot]);
- if (ret < 0)
- goto err;
-
- name_size_alg = ret;
- }
- } else {
- if (name) {
- dev_err(&chip->dev, "handle 0x%08x does not use a name\n",
- handle);
- ret = -EIO;
- goto err;
- }
- }
-
- auth->name_h[slot] = handle;
- if (name)
- memcpy(auth->name[slot], name, name_size_alg);
+ memcpy(auth->name[slot], name, name_size);
+ auth->name_size_tbl[slot] = name_size;
#endif
return 0;
#ifdef CONFIG_TCG_TPM2_HMAC
err:
tpm2_end_auth_session(chip);
- return tpm_ret_to_err(ret);
+ return ret;
#endif
}
EXPORT_SYMBOL_GPL(tpm_buf_append_name);
@@ -606,22 +596,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
attrs = chip->cc_attrs_tbl[i];
handles = (attrs >> TPM2_CC_ATTR_CHANDLES) & GENMASK(2, 0);
+ offset_s += handles * sizeof(u32);
- /*
- * just check the names, it's easy to make mistakes. This
- * would happen if someone added a handle via
- * tpm_buf_append_u32() instead of tpm_buf_append_name()
- */
- for (i = 0; i < handles; i++) {
- u32 handle = tpm_buf_read_u32(buf, &offset_s);
-
- if (auth->name_h[i] != handle) {
- dev_err(&chip->dev, "invalid handle 0x%08x\n", handle);
- ret = -EIO;
- goto err;
- }
- }
- /* point offset_s to the start of the sessions */
val = tpm_buf_read_u32(buf, &offset_s);
/* point offset_p to the start of the parameters */
offset_p = offset_s + val;
@@ -682,23 +658,8 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf)
/* ordinal is already BE */
sha256_update(&sctx, (u8 *)&head->ordinal, sizeof(head->ordinal));
/* add the handle names */
- for (i = 0; i < handles; i++) {
- enum tpm2_mso_type mso = tpm2_handle_mso(auth->name_h[i]);
-
- if (mso == TPM2_MSO_PERSISTENT ||
- mso == TPM2_MSO_VOLATILE ||
- mso == TPM2_MSO_NVRAM) {
- ret = name_size(auth->name[i]);
- if (ret < 0)
- goto err;
-
- sha256_update(&sctx, auth->name[i], ret);
- } else {
- __be32 h = cpu_to_be32(auth->name_h[i]);
-
- sha256_update(&sctx, (u8 *)&h, 4);
- }
- }
+ for (i = 0; i < handles; i++)
+ sha256_update(&sctx, auth->name[i], auth->name_size_tbl[i]);
if (offset_s != tpm_buf_length(buf))
sha256_update(&sctx, &buf->data[offset_s],
tpm_buf_length(buf) - offset_s);
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index b4b5bd586501..db716841973f 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -539,7 +539,7 @@ static inline struct tpm2_auth *tpm2_chip_auth(struct tpm_chip *chip)
}
int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
- u32 handle, u8 *name);
+ u32 handle, u8 *name, u16 name_size);
void tpm_buf_append_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf,
u8 attributes, u8 *passphrase,
int passphraselen);
@@ -553,6 +553,7 @@ int tpm_buf_fill_hmac_session(struct tpm_chip *chip, struct tpm_buf *buf);
int tpm_buf_check_hmac_response(struct tpm_chip *chip, struct tpm_buf *buf,
int rc);
void tpm2_end_auth_session(struct tpm_chip *chip);
+int tpm2_read_public(struct tpm_chip *chip, u32 handle, void *name);
#else
#include <linux/unaligned.h>
@@ -576,6 +577,13 @@ static inline int tpm_buf_check_hmac_response(struct tpm_chip *chip,
{
return rc;
}
+
+static inline int tpm2_read_public(struct tpm_chip *chip, u32 handle,
+ void *name)
+{
+ memcpy(name, &handle, sizeof(u32));
+ return sizeof(u32);
+}
#endif /* CONFIG_TCG_TPM2_HMAC */
#endif
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 9074ae1a5896..7756aa839d81 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -203,7 +203,9 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ u8 parent_name[TPM2_MAX_NAME_SIZE];
off_t offset = TPM_HEADER_SIZE;
+ u16 parent_name_size;
int blob_len = 0;
int hash;
u32 flags;
@@ -220,6 +222,12 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
if (rc)
return rc;
+ rc = tpm2_read_public(chip, options->keyhandle, parent_name);
+ if (rc < 0)
+ goto out_put;
+
+ parent_name_size = rc;
+
rc = tpm2_start_auth_session(chip);
if (rc)
goto out_put;
@@ -234,7 +242,8 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
goto out_put;
@@ -326,48 +335,38 @@ int tpm2_seal_trusted(struct tpm_chip *chip,
}
/**
- * tpm2_load_cmd() - execute a TPM2_Load command
- *
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- * @blob_handle: returned blob handle
+ * tpm2_load_cmd() - Execute TPM2_Load
+ * @chip: TPM chip to use.
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
+ * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the
+ * parent key.
+ * @blob: The decoded payload for the key.
+ * @blob_handle: On success, will contain handle to the loaded keyedhash
+ * blob.
*
- * Return: 0 on success.
- * -E2BIG on wrong payload size.
- * -EPERM on tpm error status.
- * < 0 error from tpm_send.
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails.
*/
static int tpm2_load_cmd(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options,
+ u8 *parent_name,
+ u16 parent_name_size,
+ const u8 *blob,
u32 *blob_handle)
{
u8 *blob_ref __free(kfree) = NULL;
unsigned int private_len;
unsigned int public_len;
unsigned int blob_len;
- u8 *blob, *pub;
+ const u8 *pub;
int rc;
u32 attrs;
- rc = tpm2_key_decode(payload, options, &blob);
- if (rc) {
- /* old form */
- blob = payload->blob;
- payload->old_format = 1;
- } else {
- /* Bind for cleanup: */
- blob_ref = blob;
- }
-
- /* new format carries keyhandle but old format doesn't */
- if (!options->keyhandle)
- return -EINVAL;
-
/* must be big enough for at least the two be16 size counts */
if (payload->blob_len < 4)
- return -EINVAL;
+ return -E2BIG;
private_len = get_unaligned_be16(blob);
@@ -406,7 +405,8 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
return rc;
@@ -434,20 +434,23 @@ static int tpm2_load_cmd(struct tpm_chip *chip,
}
/**
- * tpm2_unseal_cmd() - execute a TPM2_Unload command
+ * tpm2_unseal_cmd() - Execute TPM2_Unload
*
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- * @blob_handle: blob handle
+ * @chip: TPM chip to use
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
+ * @parent_name: A cryptographic name, i.e. a TPMT_HA blob, of the
+ * parent key.
+ * @blob_handle: Handle to the loaded keyedhash blob.
*
- * Return: 0 on success
- * -EPERM on tpm error status
- * < 0 error from tpm_send
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load fails.
*/
static int tpm2_unseal_cmd(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options,
+ u8 *parent_name,
+ u16 parent_name_size,
u32 blob_handle)
{
struct tpm_header *head;
@@ -467,7 +470,8 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
tpm_buf_init(buf, TPM_BUFSIZE);
tpm_buf_reset(buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL);
- rc = tpm_buf_append_name(chip, buf, options->keyhandle, NULL);
+ rc = tpm_buf_append_name(chip, buf, options->keyhandle, parent_name,
+ parent_name_size);
if (rc)
return rc;
@@ -534,30 +538,60 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
}
/**
- * tpm2_unseal_trusted() - unseal the payload of a trusted key
+ * tpm2_unseal_trusted() - Unseal a trusted key
+ * @chip: TPM chip to use.
+ * @payload: Key data in clear text.
+ * @options: Trusted key options.
*
- * @chip: TPM chip to use
- * @payload: the key data in clear and encrypted form
- * @options: authentication values and other options
- *
- * Return: Same as with tpm_send.
+ * Return -E2BIG when the blob size is too small for all the data.
+ * Return -EINVAL when parent's key handle has not been set.
+ * Returns tpm_transmit_cmd() error codes when either TPM2_Load or TPM2_Unseal
+ * fails.
*/
int tpm2_unseal_trusted(struct tpm_chip *chip,
struct trusted_key_payload *payload,
struct trusted_key_options *options)
{
+ u8 *blob_ref __free(kfree) = NULL;
+ u8 parent_name[TPM2_MAX_NAME_SIZE];
+ u16 parent_name_size;
u32 blob_handle;
+ u8 *blob;
int rc;
+ /*
+ * Try to decode the provided blob as an ASN.1 blob. Assume that the
+ * blob is in the legacy format if decoding does not end successfully.
+ */
+ rc = tpm2_key_decode(payload, options, &blob);
+ if (rc) {
+ blob = payload->blob;
+ payload->old_format = 1;
+ } else {
+ blob_ref = blob;
+ }
+
+ if (!options->keyhandle)
+ return -EINVAL;
+
rc = tpm_try_get_ops(chip);
if (rc)
return rc;
- rc = tpm2_load_cmd(chip, payload, options, &blob_handle);
+ rc = tpm2_read_public(chip, options->keyhandle, parent_name);
+ if (rc < 0)
+ goto out;
+
+ parent_name_size = rc;
+
+ rc = tpm2_load_cmd(chip, payload, options, parent_name,
+ parent_name_size, blob, &blob_handle);
if (rc)
goto out;
- rc = tpm2_unseal_cmd(chip, payload, options, blob_handle);
+ rc = tpm2_unseal_cmd(chip, payload, options, parent_name,
+ parent_name_size, blob_handle);
+
tpm2_flush_context(chip, blob_handle);
out:
--
2.52.0
^ permalink raw reply related
* Re: [PATCH] KEYS: trusted: Don't use 'buf->handles'
From: Jarkko Sakkinen @ 2025-12-09 7:19 UTC (permalink / raw)
To: linux-integrity
Cc: James Bottomley, Mimi Zohar, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, open list:KEYS-TRUSTED,
open list:SECURITY SUBSYSTEM, open list
In-Reply-To: <20251209071144.56893-1-jarkko@kernel.org>
On Tue, Dec 09, 2025 at 09:11:43AM +0200, Jarkko Sakkinen wrote:
> tpm2_unseal_trusted() deduces number of handles in run-time even tho the
> expected value is known at compile time. Address the issue.
>
> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
> ---
> security/keys/trusted-keys/trusted_tpm2.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
> index 9074ae1a5896..e78061ee2d99 100644
> --- a/security/keys/trusted-keys/trusted_tpm2.c
> +++ b/security/keys/trusted-keys/trusted_tpm2.c
> @@ -491,7 +491,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
> if (tpm2_chip_auth(chip)) {
> tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT, NULL, 0);
> } else {
> - offset = buf->handles * 4 + TPM_HEADER_SIZE;
> + offset = TPM_HEADER_SIZE + 2 * sizeof(u32);
Oops.
Should be 'TPM_HEADER_SIZE + sizeof(u32)'. There's just a single handle.
> head = (struct tpm_header *)buf->data;
> if (tpm_buf_length(buf) == offset)
> head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
> --
> 2.39.5
>
BR, Jarkko
^ permalink raw reply
* [PATCH] KEYS: trusted: Don't use 'buf->handles'
From: Jarkko Sakkinen @ 2025-12-09 7:11 UTC (permalink / raw)
To: linux-integrity
Cc: Jarkko Sakkinen, James Bottomley, Mimi Zohar, David Howells,
Paul Moore, James Morris, Serge E. Hallyn, open list:KEYS-TRUSTED,
open list:SECURITY SUBSYSTEM, open list
tpm2_unseal_trusted() deduces number of handles in run-time even tho the
expected value is known at compile time. Address the issue.
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
---
security/keys/trusted-keys/trusted_tpm2.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/security/keys/trusted-keys/trusted_tpm2.c b/security/keys/trusted-keys/trusted_tpm2.c
index 9074ae1a5896..e78061ee2d99 100644
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -491,7 +491,7 @@ static int tpm2_unseal_cmd(struct tpm_chip *chip,
if (tpm2_chip_auth(chip)) {
tpm_buf_append_hmac_session(chip, buf, TPM2_SA_ENCRYPT, NULL, 0);
} else {
- offset = buf->handles * 4 + TPM_HEADER_SIZE;
+ offset = TPM_HEADER_SIZE + 2 * sizeof(u32);
head = (struct tpm_header *)buf->data;
if (tpm_buf_length(buf) == offset)
head->tag = cpu_to_be16(TPM2_ST_NO_SESSIONS);
--
2.39.5
^ permalink raw reply related
* Re: [PATCH 1/1] IMA event log trimming
From: James Bottomley @ 2025-12-08 22:17 UTC (permalink / raw)
To: Roberto Sassu, steven chen, linux-integrity
Cc: zohar, roberto.sassu, dmitry.kasatkin, eric.snowberg, paul,
jmorris, serge, linux-security-module, anirudhve, gregorylumen,
nramas, sushring
In-Reply-To: <1ca00e3238e804db9280abf8655364c2662754ca.camel@huaweicloud.com>
On Mon, 2025-12-08 at 10:40 +0100, Roberto Sassu wrote:
> I have the impression that none the functionality you cited has to be
> implemented in the kernel, because the only component one can trust
> to verify the integrity of the IMA measurements list is the TPM.
> Whether either the kernel or user space retain the measurements is
> irrelevant.
That's correct, I'm not advocating moving quoting into the kernel. Co-
ordinating the trim with where the quote gets you to is phenomenally
useful. While you could theoretically store any mismatch in userspace,
having two locations for the log makes it more error prone.
> I believe that the only role of the kernel is to get rid of the
> measurements entries as fast as possible (the kernel would act more
> like a buffer).
I wouldn't say that, I'd say to get rid of measurements that the user
has indicated are of no further use.
> This was actually the intent of my original proposal in
> https://github.com/linux-integrity/linux/issues/1 . The idea of
> staging (was snapshotting, but Mimi thinks the term is not accurate)
> is simply to detach the entire IMA measurement list as fast as
> possible. Further read and delete after staging is done without
> interfering with new measurements (sure, the detaching of the hash
> table is not yet as efficient as I hoped).
From the application point of view, offloading the log and random
points is a bit more work because now the log collector has to be
modified to look in multiple locations and we'd also need an agreement
of where those locations are and how the log is sequenced in a naming
scheme so it's the same for every distribution. If the application is
in charge of trimming the log at a particular point, collection remains
the same (it can simply be the existing in-kernel location), so we
don't need a cross distro agreement, and the trim can simply be added
as an extra function.
Regards,
James
^ permalink raw reply
* Re: [PATCH] ipe: remove headers that are included but not used
From: Fan Wu @ 2025-12-08 19:02 UTC (permalink / raw)
To: Yicong Hui
Cc: Fan Wu, paul, jmorris, serge, linux-security-module, linux-kernel,
skhan, david.hunter.linux
In-Reply-To: <3748b276-6503-4c50-a394-e5b75c1eb7bf@gmail.com>
On Sat, Dec 6, 2025 at 1:04 PM Yicong Hui <yiconghui@gmail.com> wrote:
>
> On 12/3/25 10:25 PM, Fan Wu wrote:
> > On Wed, Dec 3, 2025 at 11:37 AM Yicong Hui <yiconghui@gmail.com> wrote:
> >
> > Hi Yicong,
> >
> > Thanks for the patch. This kind of cleanup is appreciated.
> >
> > Commit message typo: "audit. c, audit.c, policy. c" - audit. c is listed
> > twice.
>
> Hi! Thank you for the reply! Yes! My bad, this typo will be fixed in v2.
>
...
>
> I have manually read through the functions/macros/filetypes in policy.c,
> policy_fs.c and audit.c and found a few dependencies that are used but
> not explicitly included, like minmax.h, sha2.h, lockdep.h, string.h,
> capability.h, kstrtox.h, sprintf.h, array_size.h and err.h.
>
> This might be a stupid question, but how explicit should I be in my v2
> patch with the dependencies? There's headers like
> "asm-generic/int-ll64.h" "uidgid.h", "gfp_types.h", "rwonce.h",
> "compiler_types.h" or "errno-base.h" but I'm not sure to what extent I
> need to import them, because I shouldn't be including them all, right?
Hi Yicong,
On second thought, the cost of this cleanup outweighs the benefit.
Let's drop this patch and keep the code as it is.
-Fan
^ permalink raw reply
* Re: [PATCH] KEYS: trusted: Fix overwrite of keyhandle parameter
From: Jarkko Sakkinen @ 2025-12-08 18:56 UTC (permalink / raw)
To: linux-integrity
Cc: stable, James Bottomley, Mimi Zohar, David Howells, Paul Moore,
James Morris, Serge E. Hallyn, open list:KEYS-TRUSTED,
open list:SECURITY SUBSYSTEM, open list
In-Reply-To: <20251208145436.21519-1-jarkko@kernel.org>
On Mon, Dec 08, 2025 at 04:54:35PM +0200, Jarkko Sakkinen wrote:
> tpm2_key_decode() overrides the explicit keyhandle parameter, which can
> lead to problems, if the loaded parent handle does not match the handle
> stored to the key file. This can easily happen as handle by definition
> is an ambiguous attribute.
>
> Cc: stable@vger.kernel.org # v5.13+
> Fixes: f2219745250f ("security: keys: trusted: use ASN.1 TPM2 key format for the blobs")
> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
What this means in practice is that sometimes you need either to:
1. Binary patch the key file.
2. Decompose/compose a key file
BR, Jarkko
^ permalink raw reply
* Re: [PATCH 1/1] IMA event log trimming
From: Roberto Sassu @ 2025-12-08 17:50 UTC (permalink / raw)
To: Gregory Lumen
Cc: James Bottomley, steven chen, linux-integrity, zohar,
roberto.sassu, dmitry.kasatkin, eric.snowberg, paul, jmorris,
serge, linux-security-module, anirudhve, nramas, sushring
In-Reply-To: <862fa081-df51-084-ae2c-efa0eae0ca7e@linux.microsoft.com>
On Mon, 2025-12-08 at 09:21 -0800, Gregory Lumen wrote:
> > Rather than designing the interface absent use cases, could we give use
> > cases first so we know it fits?
>
> I would also like to request that we include operational considerations in
> the interface design; specifically, which additional signals can or should
> be made available to UM to assist in diagnosing log validation failures.
> This seems called for as any form of log trimming will introduce a new
> potential cause for validation failures (unexpected trimming).
>
> With the proposed changes, the only signal available to system operators
> is the validation failure itself, with no signal that could be used to
> determine if the failure was the result of an unexpected trim or a loss of
> synchronization between the log and the PCRs (either through an unexpected
> PCR extend, or tampering with the measurement list). Any of these may
> indicate malicious activity, but they may also result from system
> configuration issues that operators would need to diagnose and resolve.
I don't agree with this. User space can keep a persistent state, and
resume from where it was interrupted. There is no risk of loss of data,
if user space deletes staged measurements only after the read is
complete.
The same comment applies for coordination between different user space
agents. It would not be too hard to expose an interface managed by a
new user space component, providing similar data as IMA (even showing
the full measurements list without its users being aware of the
snapshots). The other agents can fetch the data from the new interface.
And also, I don't see the problem in developing more complex user space
programs which link the measurement entries to PCR values, and anything
that is desirable.
And if from the kernel perspective all we need to do is a list replace,
for me that is the most efficient solution.
Roberto
> Tracking and exposing either the total number of trimmed measurements or
> the most recent trimmed-to PCR values by the kernel would allow system
> operators to determine whether a failure was caused by unexpected trimming
> or integrity issues. (Storing the PCR values also enables validation of
> the retained measurements even after an unexpected trim, though I’m unsure
> how often that signal would prove useful.)
>
> Neither approach appears to add any additional attack surface beyond
> raising the likelihood of incorrectly or insecurely implemented UM
> attestation agents. Though that risk (and the additional kernel
> complexity) should be weighed against the value of the additional
> diagnostic signals.
>
> -Gregory Lumen
^ permalink raw reply
* Re: [PATCH 1/1] IMA event log trimming
From: Gregory Lumen @ 2025-12-08 17:21 UTC (permalink / raw)
To: Roberto Sassu
Cc: James Bottomley, steven chen, linux-integrity, zohar,
roberto.sassu, dmitry.kasatkin, eric.snowberg, paul, jmorris,
serge, linux-security-module, anirudhve, nramas, sushring
In-Reply-To: <1ca00e3238e804db9280abf8655364c2662754ca.camel@huaweicloud.com>
[-- Attachment #1: Type: text/plain, Size: 1701 bytes --]
> Rather than designing the interface absent use cases, could we give use
> cases first so we know it fits?
I would also like to request that we include operational considerations in
the interface design; specifically, which additional signals can or should
be made available to UM to assist in diagnosing log validation failures.
This seems called for as any form of log trimming will introduce a new
potential cause for validation failures (unexpected trimming).
With the proposed changes, the only signal available to system operators
is the validation failure itself, with no signal that could be used to
determine if the failure was the result of an unexpected trim or a loss of
synchronization between the log and the PCRs (either through an unexpected
PCR extend, or tampering with the measurement list). Any of these may
indicate malicious activity, but they may also result from system
configuration issues that operators would need to diagnose and resolve.
Tracking and exposing either the total number of trimmed measurements or
the most recent trimmed-to PCR values by the kernel would allow system
operators to determine whether a failure was caused by unexpected trimming
or integrity issues. (Storing the PCR values also enables validation of
the retained measurements even after an unexpected trim, though I’m unsure
how often that signal would prove useful.)
Neither approach appears to add any additional attack surface beyond
raising the likelihood of incorrectly or insecurely implemented UM
attestation agents. Though that risk (and the additional kernel
complexity) should be weighed against the value of the additional
diagnostic signals.
-Gregory Lumen
^ permalink raw reply
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