From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Berger Subject: Re: [PATCH v6 2/3] tpm: vtpm_proxy: Implement request_locality function. Date: Thu, 1 Jun 2017 20:34:31 -0400 Message-ID: <22d2ce2e-6636-82ad-3099-5f947bc70e05@linux.vnet.ibm.com> References: <1495661981-27249-1-git-send-email-stefanb@linux.vnet.ibm.com> <1495661981-27249-3-git-send-email-stefanb@linux.vnet.ibm.com> <20170524222130.cqnt433dbrr3t43i@intel.com> <20170525000936.djj37wyqieorjfva@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170525000936.djj37wyqieorjfva@intel.com> Sender: owner-linux-security-module@vger.kernel.org To: Jarkko Sakkinen Cc: tpmdd-devel@lists.sourceforge.net, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, jgunthorpe@obsidianresearch.com List-Id: tpmdd-devel@lists.sourceforge.net On 05/24/2017 08:09 PM, Jarkko Sakkinen wrote: > On Wed, May 24, 2017 at 07:03:27PM -0400, Stefan Berger wrote: >> On 05/24/2017 06:21 PM, Jarkko Sakkinen wrote: >>> On Wed, May 24, 2017 at 05:39:40PM -0400, Stefan Berger wrote: >>>> Implement the request_locality function. To set the locality on the >>>> backend we define vendor-specific TPM 1.2 and TPM 2 ordinals and send >>>> a command to the backend to set the locality for the next commands. >>>> >>>> To avoid recursing into requesting the locality, we set the >>>> TPM_TRANSMIT_RAW flag when calling tpm_transmit_cmd. To avoid recursing >>>> into TPM 2 space related commands, we set the space parameter to NULL. >>>> >>>> Signed-off-by: Stefan Berger >>>> --- >>>> drivers/char/tpm/tpm-interface.c | 1 + >>>> drivers/char/tpm/tpm_vtpm_proxy.c | 36 ++++++++++++++++++++++++++++++++++++ >>>> include/uapi/linux/vtpm_proxy.h | 4 ++++ >>>> 3 files changed, 41 insertions(+) >>>> >>>> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c >>>> index 2eacda2..876d45f 100644 >>>> --- a/drivers/char/tpm/tpm-interface.c >>>> +++ b/drivers/char/tpm/tpm-interface.c >>>> @@ -537,6 +537,7 @@ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space, >>>> return 0; >>>> } >>>> +EXPORT_SYMBOL_GPL(tpm_transmit_cmd); >>>> #define TPM_DIGEST_SIZE 20 >>>> #define TPM_RET_CODE_IDX 6 >>>> diff --git a/drivers/char/tpm/tpm_vtpm_proxy.c b/drivers/char/tpm/tpm_vtpm_proxy.c >>>> index 751059d..66024bf 100644 >>>> --- a/drivers/char/tpm/tpm_vtpm_proxy.c >>>> +++ b/drivers/char/tpm/tpm_vtpm_proxy.c >>>> @@ -371,6 +371,41 @@ static bool vtpm_proxy_tpm_req_canceled(struct tpm_chip *chip, u8 status) >>>> return ret; >>>> } >>>> +static int vtpm_proxy_request_locality(struct tpm_chip *chip, int locality) >>>> +{ >>>> + struct tpm_buf buf; >>>> + int rc; >>>> + const struct tpm_output_header *header; >>>> + >>>> + if (chip->flags & TPM_CHIP_FLAG_TPM2) >>>> + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, >>>> + TPM2_CC_SET_LOCALITY); >>> I would always go with this branch. >>> >>>> + else >>>> + rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, >>>> + TPM_ORD_SET_LOCALITY); >>>> + if (rc) >>>> + return rc; >>>> + tpm_buf_append_u8(&buf, locality); >>>> + >>>> + rc = tpm_transmit_cmd(chip, NULL, buf.data, tpm_buf_length(&buf), 0, >>>> + TPM_TRANSMIT_UNLOCKED | TPM_TRANSMIT_RAW, >>>> + "attempting to set locality"); >>>> + if (rc < 0) { >>>> + locality = rc; >>>> + goto out; >>>> + } >>>> + >>>> + header = (const struct tpm_output_header *)buf.data; >>>> + rc = be32_to_cpu(header->return_code); >>>> + if (rc) >>>> + locality = -1; >>>> + >>>> +out: >>>> + tpm_buf_destroy(&buf); >>>> + >>>> + return locality; >>>> +} >>>> + >>>> static const struct tpm_class_ops vtpm_proxy_tpm_ops = { >>>> .flags = TPM_OPS_AUTO_STARTUP, >>>> .recv = vtpm_proxy_tpm_op_recv, >>>> @@ -380,6 +415,7 @@ static const struct tpm_class_ops vtpm_proxy_tpm_ops = { >>>> .req_complete_mask = VTPM_PROXY_REQ_COMPLETE_FLAG, >>>> .req_complete_val = VTPM_PROXY_REQ_COMPLETE_FLAG, >>>> .req_canceled = vtpm_proxy_tpm_req_canceled, >>>> + .request_locality = vtpm_proxy_request_locality, >>>> }; >>>> /* >>>> diff --git a/include/uapi/linux/vtpm_proxy.h b/include/uapi/linux/vtpm_proxy.h >>>> index a69e991..58ac73c 100644 >>>> --- a/include/uapi/linux/vtpm_proxy.h >>>> +++ b/include/uapi/linux/vtpm_proxy.h >>>> @@ -46,4 +46,8 @@ struct vtpm_proxy_new_dev { >>>> #define VTPM_PROXY_IOC_NEW_DEV _IOWR(0xa1, 0x00, struct vtpm_proxy_new_dev) >>>> +/* vendor specific commands to set locality */ >>>> +#define TPM2_CC_SET_LOCALITY 0x20001000 >>>> +#define TPM_ORD_SET_LOCALITY 0x20001000 >>>> + >>>> #endif /* _UAPI_LINUX_VTPM_PROXY_H */ >>>> -- >>>> 2.4.3 >>> What practical benefit you get from these two constants? I understand >>> the value range but not so much the redundant code. >> If you want to change this, please go ahead and give it a sinle name. >> For the code branches above I think that we should at least send a TPM 1.2 >> formatted command in case of TPM 1.2 and a TPM 2 formatted one in case of >> TPM 2. It seems just 'proper.' >> >> Stefan > Agreed. I will make these changes no need to send new series. I pushed an update to the test suite, which may help the cause to accept this series. https://github.com/stefanberger/linux-vtpm-tests Patch 3/3 should probably not return -EFAULT in case of the user trying to send the SetLocality command via /dev/tpm%d but rather -EPIPE to get the logging of the error suppressed, even though that doesn't seem to be the right error code. Stefan > > Reviewed-by: Jarkko Sakkinen > > /Jarkko >