From: Stefano Garzarella Date: Fri, 20 Jun 2025 13:08:09 +0000 (+0200) Subject: tpm/tpm_ftpm_tee: support TPM_CHIP_FLAG_SYNC X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0637c10e72ef4b0645cb45873d21fd5f711ba041;p=thirdparty%2Flinux.git tpm/tpm_ftpm_tee: support TPM_CHIP_FLAG_SYNC This driver does not support interrupts, and receiving the response is synchronous with sending the command. Enable synchronous send() with TPM_CHIP_FLAG_SYNC, which implies that ->send() already fills the provided buffer with a response, and ->recv() is not implemented. Signed-off-by: Stefano Garzarella Reviewed-by: Sumit Garg Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c index dbad83bf798ed..4e63c30aeaf14 100644 --- a/drivers/char/tpm/tpm_ftpm_tee.c +++ b/drivers/char/tpm/tpm_ftpm_tee.c @@ -31,47 +31,19 @@ static const uuid_t ftpm_ta_uuid = 0x82, 0xCB, 0x34, 0x3F, 0xB7, 0xF3, 0x78, 0x96); /** - * ftpm_tee_tpm_op_recv() - retrieve fTPM response. - * @chip: the tpm_chip description as specified in driver/char/tpm/tpm.h. - * @buf: the buffer to store data. - * @count: the number of bytes to read. - * - * Return: - * In case of success the number of bytes received. - * On failure, -errno. - */ -static int ftpm_tee_tpm_op_recv(struct tpm_chip *chip, u8 *buf, size_t count) -{ - struct ftpm_tee_private *pvt_data = dev_get_drvdata(chip->dev.parent); - size_t len; - - len = pvt_data->resp_len; - if (count < len) { - dev_err(&chip->dev, - "%s: Invalid size in recv: count=%zd, resp_len=%zd\n", - __func__, count, len); - return -EIO; - } - - memcpy(buf, pvt_data->resp_buf, len); - pvt_data->resp_len = 0; - - return len; -} - -/** - * ftpm_tee_tpm_op_send() - send TPM commands through the TEE shared memory. + * ftpm_tee_tpm_op_send() - send TPM commands through the TEE shared memory + * and retrieve the response. * @chip: the tpm_chip description as specified in driver/char/tpm/tpm.h - * @buf: the buffer to send. + * @buf: the buffer to send and to store the response. * @bufsiz: the size of the buffer. - * @len: the number of bytes to send. + * @cmd_len: the number of bytes to send. * * Return: - * In case of success, returns 0. + * In case of success, returns the number of bytes received. * On failure, -errno */ static int ftpm_tee_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, - size_t len) + size_t cmd_len) { struct ftpm_tee_private *pvt_data = dev_get_drvdata(chip->dev.parent); size_t resp_len; @@ -82,16 +54,15 @@ static int ftpm_tee_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, struct tee_param command_params[4]; struct tee_shm *shm = pvt_data->shm; - if (len > MAX_COMMAND_SIZE) { + if (cmd_len > MAX_COMMAND_SIZE) { dev_err(&chip->dev, "%s: len=%zd exceeds MAX_COMMAND_SIZE supported by fTPM TA\n", - __func__, len); + __func__, cmd_len); return -EIO; } memset(&transceive_args, 0, sizeof(transceive_args)); memset(command_params, 0, sizeof(command_params)); - pvt_data->resp_len = 0; /* Invoke FTPM_OPTEE_TA_SUBMIT_COMMAND function of fTPM TA */ transceive_args = (struct tee_ioctl_invoke_arg) { @@ -105,7 +76,7 @@ static int ftpm_tee_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, .attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INPUT, .u.memref = { .shm = shm, - .size = len, + .size = cmd_len, .shm_offs = 0, }, }; @@ -117,7 +88,7 @@ static int ftpm_tee_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, return PTR_ERR(temp_buf); } memset(temp_buf, 0, (MAX_COMMAND_SIZE + MAX_RESPONSE_SIZE)); - memcpy(temp_buf, buf, len); + memcpy(temp_buf, buf, cmd_len); command_params[1] = (struct tee_param) { .attr = TEE_IOCTL_PARAM_ATTR_TYPE_MEMREF_INOUT, @@ -158,17 +129,20 @@ static int ftpm_tee_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, __func__, resp_len); return -EIO; } + if (resp_len > bufsiz) { + dev_err(&chip->dev, + "%s: resp_len=%zd exceeds bufsiz=%zd\n", + __func__, resp_len, bufsiz); + return -EIO; + } - /* sanity checks look good, cache the response */ - memcpy(pvt_data->resp_buf, temp_buf, resp_len); - pvt_data->resp_len = resp_len; + memcpy(buf, temp_buf, resp_len); - return 0; + return resp_len; } static const struct tpm_class_ops ftpm_tee_tpm_ops = { .flags = TPM_OPS_AUTO_STARTUP, - .recv = ftpm_tee_tpm_op_recv, .send = ftpm_tee_tpm_op_send, }; @@ -253,7 +227,7 @@ static int ftpm_tee_probe(struct device *dev) } pvt_data->chip = chip; - pvt_data->chip->flags |= TPM_CHIP_FLAG_TPM2; + pvt_data->chip->flags |= TPM_CHIP_FLAG_TPM2 | TPM_CHIP_FLAG_SYNC; /* Create a character device for the fTPM */ rc = tpm_chip_register(pvt_data->chip); diff --git a/drivers/char/tpm/tpm_ftpm_tee.h b/drivers/char/tpm/tpm_ftpm_tee.h index e39903b7ea071..8d5c3f0d28794 100644 --- a/drivers/char/tpm/tpm_ftpm_tee.h +++ b/drivers/char/tpm/tpm_ftpm_tee.h @@ -22,16 +22,12 @@ * struct ftpm_tee_private - fTPM's private data * @chip: struct tpm_chip instance registered with tpm framework. * @session: fTPM TA session identifier. - * @resp_len: cached response buffer length. - * @resp_buf: cached response buffer. * @ctx: TEE context handler. * @shm: Memory pool shared with fTPM TA in TEE. */ struct ftpm_tee_private { struct tpm_chip *chip; u32 session; - size_t resp_len; - u8 resp_buf[MAX_RESPONSE_SIZE]; struct tee_context *ctx; struct tee_shm *shm; };