| Message ID | 20220309122800.3940001-4-sughosh.ganu@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | tpm: rng: Move TPM RNG functionality to driver model | expand |
Hi Sughosh, On Wed, 9 Mar 2022 at 05:28, Sughosh Ganu <sughosh.ganu@linaro.org> wrote: > > The TPM device has a builtin random number generator(RNG) > functionality. Expose the RNG functions of the TPM device to the > driver model so that they can be used by the EFI_RNG_PROTOCOL if the > protocol is installed. > > Also change the function arguments and return type of the random > number functions to comply with the driver model api. > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > --- > > Changes since V3: > > * Move back the driver model interface for the TPM RNG devices under > drivers/rng/ directory. > * Add a rng read function for the tpm devices which calls the > tpm*_get_random API's. > * Pass the TPM device pointer to the tpm*_get_random API's from the > TPM RNG drivers as suggested by Simon. > > drivers/rng/Makefile | 2 ++ > drivers/rng/tpm1_rng.c | 24 ++++++++++++++++++++++++ > drivers/rng/tpm2_rng.c | 23 +++++++++++++++++++++++ > include/tpm-v1.h | 4 ++-- > include/tpm-v2.h | 4 ++-- > lib/tpm-v1.c | 16 +++++++++------- > lib/tpm-v2.c | 9 +++++---- > lib/tpm_api.c | 23 +++++++++++++++++++---- > 8 files changed, 86 insertions(+), 19 deletions(-) > create mode 100644 drivers/rng/tpm1_rng.c > create mode 100644 drivers/rng/tpm2_rng.c > > diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile > index 39f7ee3f03..c91e4e1701 100644 > --- a/drivers/rng/Makefile > +++ b/drivers/rng/Makefile > @@ -10,3 +10,5 @@ obj-$(CONFIG_RNG_MSM) += msm_rng.o > obj-$(CONFIG_RNG_STM32MP1) += stm32mp1_rng.o > obj-$(CONFIG_RNG_ROCKCHIP) += rockchip_rng.o > obj-$(CONFIG_RNG_IPROC200) += iproc_rng200.o > +obj-$(CONFIG_TPM_V1) += tpm1_rng.o > +obj-$(CONFIG_TPM_V2) += tpm2_rng.o > diff --git a/drivers/rng/tpm1_rng.c b/drivers/rng/tpm1_rng.c > new file mode 100644 > index 0000000000..b827e2d1c1 > --- /dev/null > +++ b/drivers/rng/tpm1_rng.c > @@ -0,0 +1,24 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2022, Linaro Limited > + */ > + > +#include <dm.h> > +#include <rng.h> > +#include <tpm-v1.h> > + > +static int rng_tpm1_random_read(struct udevice *dev, void *data, size_t count) > +{ > + return tpm1_get_random(dev->parent, data, count); > +} > + > +static const struct dm_rng_ops tpm1_rng_ops = { > + .read = rng_tpm1_random_read, > +}; > + > +U_BOOT_DRIVER(tpm1_rng) = { > + .name = "tpm1-rng", > + .id = UCLASS_RNG, > + .ops = &tpm1_rng_ops, > +}; > + > diff --git a/drivers/rng/tpm2_rng.c b/drivers/rng/tpm2_rng.c > new file mode 100644 > index 0000000000..bd1fd539f0 > --- /dev/null > +++ b/drivers/rng/tpm2_rng.c > @@ -0,0 +1,23 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Copyright (c) 2022, Linaro Limited > + */ > + > +#include <dm.h> > +#include <rng.h> > +#include <tpm-v2.h> > + > +static int rng_tpm2_random_read(struct udevice *dev, void *data, size_t count) > +{ > + return tpm2_get_random(dev->parent, data, count); > +} > + > +static const struct dm_rng_ops tpm2_rng_ops = { > + .read = rng_tpm2_random_read, > +}; > + > +U_BOOT_DRIVER(tpm2_rng) = { > + .name = "tpm2-rng", > + .id = UCLASS_RNG, > + .ops = &tpm2_rng_ops, > +}; Can't you just have one driver and have a tpm_get_random() function in tpm_api.h ? > diff --git a/include/tpm-v1.h b/include/tpm-v1.h > index 33d53fb695..d2ff8b446d 100644 > --- a/include/tpm-v1.h > +++ b/include/tpm-v1.h > @@ -555,9 +555,9 @@ u32 tpm1_find_key_sha1(struct udevice *dev, const u8 auth[20], > * @param dev TPM device > * @param data output buffer for the random bytes > * @param count size of output buffer > - * Return: return code of the operation > + * Return: 0 if OK, -ve on error > */ > -u32 tpm1_get_random(struct udevice *dev, void *data, u32 count); > +int tpm1_get_random(struct udevice *dev, void *data, size_t count); > > /** > * tpm_finalise_physical_presence() - Finalise physical presence > diff --git a/include/tpm-v2.h b/include/tpm-v2.h > index e79c90b939..4fb1e7a948 100644 > --- a/include/tpm-v2.h > +++ b/include/tpm-v2.h > @@ -619,9 +619,9 @@ u32 tpm2_pcr_setauthvalue(struct udevice *dev, const char *pw, > * @param data output buffer for the random bytes > * @param count size of output buffer > * > - * Return: return code of the operation > + * Return: 0 if OK, -ve on error > */ > -u32 tpm2_get_random(struct udevice *dev, void *data, u32 count); > +int tpm2_get_random(struct udevice *dev, void *data, size_t count); Do you need to change these? It would be better if the caller dealt with this. > > /** > * Lock data in the TPM > diff --git a/lib/tpm-v1.c b/lib/tpm-v1.c > index 22a769c587..4c6bc31a64 100644 > --- a/lib/tpm-v1.c > +++ b/lib/tpm-v1.c > @@ -9,12 +9,14 @@ > #include <common.h> > #include <dm.h> > #include <log.h> > -#include <asm/unaligned.h> > -#include <u-boot/sha1.h> > +#include <rng.h> > #include <tpm-common.h> > #include <tpm-v1.h> > #include "tpm-utils.h" > > +#include <asm/unaligned.h> > +#include <u-boot/sha1.h> > + > #ifdef CONFIG_TPM_AUTH_SESSIONS > > #ifndef CONFIG_SHA1 > @@ -869,7 +871,7 @@ u32 tpm1_find_key_sha1(struct udevice *dev, const u8 auth[20], > > #endif /* CONFIG_TPM_AUTH_SESSIONS */ > > -u32 tpm1_get_random(struct udevice *dev, void *data, u32 count) > +int tpm1_get_random(struct udevice *dev, void *data, size_t count) > { > const u8 command[14] = { > 0x0, 0xc1, /* TPM_TAG */ > @@ -892,19 +894,19 @@ u32 tpm1_get_random(struct udevice *dev, void *data, u32 count) > if (pack_byte_string(buf, sizeof(buf), "sd", > 0, command, sizeof(command), > length_offset, this_bytes)) > - return TPM_LIB_ERROR; > + return -EIO; > err = tpm_sendrecv_command(dev, buf, response, > &response_length); > if (err) > return err; > if (unpack_byte_string(response, response_length, "d", > data_size_offset, &data_size)) > - return TPM_LIB_ERROR; > + return -EIO; > if (data_size > count) > - return TPM_LIB_ERROR; > + return -EIO; > if (unpack_byte_string(response, response_length, "s", > data_offset, out, data_size)) > - return TPM_LIB_ERROR; > + return -EIO; > > count -= data_size; > out += data_size; > diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c > index 1bf627853a..d7a23ccf7e 100644 > --- a/lib/tpm-v2.c > +++ b/lib/tpm-v2.c > @@ -6,6 +6,7 @@ > > #include <common.h> > #include <dm.h> > +#include <rng.h> > #include <tpm-common.h> > #include <tpm-v2.h> > #include <linux/bitops.h> > @@ -562,7 +563,7 @@ u32 tpm2_pcr_setauthvalue(struct udevice *dev, const char *pw, > return tpm_sendrecv_command(dev, command_v2, NULL, NULL); > } > > -u32 tpm2_get_random(struct udevice *dev, void *data, u32 count) > +int tpm2_get_random(struct udevice *dev, void *data, size_t count) > { > const u8 command_v2[10] = { > tpm_u16(TPM2_ST_NO_SESSIONS), > @@ -585,19 +586,19 @@ u32 tpm2_get_random(struct udevice *dev, void *data, u32 count) > if (pack_byte_string(buf, sizeof(buf), "sw", > 0, command_v2, sizeof(command_v2), > sizeof(command_v2), this_bytes)) > - return TPM_LIB_ERROR; > + return -EIO; > err = tpm_sendrecv_command(dev, buf, response, > &response_length); > if (err) > return err; > if (unpack_byte_string(response, response_length, "w", > data_size_offset, &data_size)) > - return TPM_LIB_ERROR; > + return -EIO; > if (data_size > this_bytes) > return TPM_LIB_ERROR; > if (unpack_byte_string(response, response_length, "s", > data_offset, out, data_size)) > - return TPM_LIB_ERROR; > + return -EIO; > > count -= data_size; > out += data_size; > diff --git a/lib/tpm_api.c b/lib/tpm_api.c > index da48058abe..3584fda98c 100644 > --- a/lib/tpm_api.c > +++ b/lib/tpm_api.c > @@ -6,6 +6,7 @@ > #include <common.h> > #include <dm.h> > #include <log.h> > +#include <rng.h> > #include <tpm_api.h> > #include <tpm-v1.h> > #include <tpm-v2.h> > @@ -265,12 +266,26 @@ u32 tpm_get_permissions(struct udevice *dev, u32 index, u32 *perm) > return -ENOSYS; > } > > +#if CONFIG_IS_ENABLED(DM_RNG) > int tpm_get_random(struct udevice *dev, void *data, u32 count) This is the function you should call > { > + int ret = -ENOSYS; > + struct udevice *rng_dev; > + > if (tpm_is_v1(dev)) > - return tpm1_get_random(dev, data, count); > + ret = uclass_get_device_by_driver(UCLASS_RNG, > + DM_DRIVER_GET(tpm1_rng), > + &rng_dev); What is going on here? This code should stay the same. Why would you go off and hunt for the device? > else if (tpm_is_v2(dev)) > - return -ENOSYS; /* not implemented yet */ It is implemented above > - else > - return -ENOSYS; > + ret = uclass_get_device_by_driver(UCLASS_RNG, > + DM_DRIVER_GET(tpm1_rng), > + &rng_dev); > + > + if (ret) { > + log_err("Getting tpm rng device failed\n"); > + return ret; > + } > + > + return dm_rng_read(rng_dev, data, (size_t)count); ?? Don't you want to call the TPM to get the random number? I am just lost. > } > +#endif /* DM_RNG */ > -- > 2.25.1 > Regards, Simon
hi Simon, On Sat, 12 Mar 2022 at 08:14, Simon Glass <sjg@chromium.org> wrote: > > Hi Sughosh, > > On Wed, 9 Mar 2022 at 05:28, Sughosh Ganu <sughosh.ganu@linaro.org> wrote: > > > > The TPM device has a builtin random number generator(RNG) > > functionality. Expose the RNG functions of the TPM device to the > > driver model so that they can be used by the EFI_RNG_PROTOCOL if the > > protocol is installed. > > > > Also change the function arguments and return type of the random > > number functions to comply with the driver model api. > > > > Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> > > --- > > > > Changes since V3: > > > > * Move back the driver model interface for the TPM RNG devices under > > drivers/rng/ directory. > > * Add a rng read function for the tpm devices which calls the > > tpm*_get_random API's. > > * Pass the TPM device pointer to the tpm*_get_random API's from the > > TPM RNG drivers as suggested by Simon. > > > > drivers/rng/Makefile | 2 ++ > > drivers/rng/tpm1_rng.c | 24 ++++++++++++++++++++++++ > > drivers/rng/tpm2_rng.c | 23 +++++++++++++++++++++++ > > include/tpm-v1.h | 4 ++-- > > include/tpm-v2.h | 4 ++-- > > lib/tpm-v1.c | 16 +++++++++------- > > lib/tpm-v2.c | 9 +++++---- > > lib/tpm_api.c | 23 +++++++++++++++++++---- > > 8 files changed, 86 insertions(+), 19 deletions(-) > > create mode 100644 drivers/rng/tpm1_rng.c > > create mode 100644 drivers/rng/tpm2_rng.c <snip> > > +static int rng_tpm2_random_read(struct udevice *dev, void *data, size_t count) > > +{ > > + return tpm2_get_random(dev->parent, data, count); > > +} > > + > > +static const struct dm_rng_ops tpm2_rng_ops = { > > + .read = rng_tpm2_random_read, > > +}; > > + > > +U_BOOT_DRIVER(tpm2_rng) = { > > + .name = "tpm2-rng", > > + .id = UCLASS_RNG, > > + .ops = &tpm2_rng_ops, > > +}; > > Can't you just have one driver and have a tpm_get_random() function in > tpm_api.h ? With a call to tpm_get_random we can, yes. > > > diff --git a/include/tpm-v1.h b/include/tpm-v1.h > > index 33d53fb695..d2ff8b446d 100644 > > --- a/include/tpm-v1.h > > +++ b/include/tpm-v1.h > > @@ -555,9 +555,9 @@ u32 tpm1_find_key_sha1(struct udevice *dev, const u8 auth[20], > > * @param dev TPM device > > * @param data output buffer for the random bytes > > * @param count size of output buffer > > - * Return: return code of the operation > > + * Return: 0 if OK, -ve on error > > */ > > -u32 tpm1_get_random(struct udevice *dev, void *data, u32 count); > > +int tpm1_get_random(struct udevice *dev, void *data, size_t count); > > > > /** > > * tpm_finalise_physical_presence() - Finalise physical presence > > diff --git a/include/tpm-v2.h b/include/tpm-v2.h > > index e79c90b939..4fb1e7a948 100644 > > --- a/include/tpm-v2.h > > +++ b/include/tpm-v2.h > > @@ -619,9 +619,9 @@ u32 tpm2_pcr_setauthvalue(struct udevice *dev, const char *pw, > > * @param data output buffer for the random bytes > > * @param count size of output buffer > > * > > - * Return: return code of the operation > > + * Return: 0 if OK, -ve on error > > */ > > -u32 tpm2_get_random(struct udevice *dev, void *data, u32 count); > > +int tpm2_get_random(struct udevice *dev, void *data, size_t count); > > Do you need to change these? It would be better if the caller dealt with this. I am putting these functions in line with the RNG uclass interface which has the count parameter as a size_t data type. > > > > > /** > > * Lock data in the TPM > > diff --git a/lib/tpm-v1.c b/lib/tpm-v1.c > > index 22a769c587..4c6bc31a64 100644 > > --- a/lib/tpm-v1.c > > +++ b/lib/tpm-v1.c > > @@ -9,12 +9,14 @@ > > #include <common.h> > > #include <dm.h> > > #include <log.h> > > -#include <asm/unaligned.h> > > -#include <u-boot/sha1.h> > > +#include <rng.h> > > #include <tpm-common.h> > > #include <tpm-v1.h> > > #include "tpm-utils.h" > > > > +#include <asm/unaligned.h> > > +#include <u-boot/sha1.h> > > + > > #ifdef CONFIG_TPM_AUTH_SESSIONS > > > > #ifndef CONFIG_SHA1 > > @@ -869,7 +871,7 @@ u32 tpm1_find_key_sha1(struct udevice *dev, const u8 auth[20], > > > > #endif /* CONFIG_TPM_AUTH_SESSIONS */ > > > > -u32 tpm1_get_random(struct udevice *dev, void *data, u32 count) > > +int tpm1_get_random(struct udevice *dev, void *data, size_t count) > > { > > const u8 command[14] = { > > 0x0, 0xc1, /* TPM_TAG */ > > @@ -892,19 +894,19 @@ u32 tpm1_get_random(struct udevice *dev, void *data, u32 count) > > if (pack_byte_string(buf, sizeof(buf), "sd", > > 0, command, sizeof(command), > > length_offset, this_bytes)) > > - return TPM_LIB_ERROR; > > + return -EIO; > > err = tpm_sendrecv_command(dev, buf, response, > > &response_length); > > if (err) > > return err; > > if (unpack_byte_string(response, response_length, "d", > > data_size_offset, &data_size)) > > - return TPM_LIB_ERROR; > > + return -EIO; > > if (data_size > count) > > - return TPM_LIB_ERROR; > > + return -EIO; > > if (unpack_byte_string(response, response_length, "s", > > data_offset, out, data_size)) > > - return TPM_LIB_ERROR; > > + return -EIO; > > > > count -= data_size; > > out += data_size; > > diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c > > index 1bf627853a..d7a23ccf7e 100644 > > --- a/lib/tpm-v2.c > > +++ b/lib/tpm-v2.c > > @@ -6,6 +6,7 @@ > > > > #include <common.h> > > #include <dm.h> > > +#include <rng.h> > > #include <tpm-common.h> > > #include <tpm-v2.h> > > #include <linux/bitops.h> > > @@ -562,7 +563,7 @@ u32 tpm2_pcr_setauthvalue(struct udevice *dev, const char *pw, > > return tpm_sendrecv_command(dev, command_v2, NULL, NULL); > > } > > > > -u32 tpm2_get_random(struct udevice *dev, void *data, u32 count) > > +int tpm2_get_random(struct udevice *dev, void *data, size_t count) > > { > > const u8 command_v2[10] = { > > tpm_u16(TPM2_ST_NO_SESSIONS), > > @@ -585,19 +586,19 @@ u32 tpm2_get_random(struct udevice *dev, void *data, u32 count) > > if (pack_byte_string(buf, sizeof(buf), "sw", > > 0, command_v2, sizeof(command_v2), > > sizeof(command_v2), this_bytes)) > > - return TPM_LIB_ERROR; > > + return -EIO; > > err = tpm_sendrecv_command(dev, buf, response, > > &response_length); > > if (err) > > return err; > > if (unpack_byte_string(response, response_length, "w", > > data_size_offset, &data_size)) > > - return TPM_LIB_ERROR; > > + return -EIO; > > if (data_size > this_bytes) > > return TPM_LIB_ERROR; > > if (unpack_byte_string(response, response_length, "s", > > data_offset, out, data_size)) > > - return TPM_LIB_ERROR; > > + return -EIO; > > > > count -= data_size; > > out += data_size; > > diff --git a/lib/tpm_api.c b/lib/tpm_api.c > > index da48058abe..3584fda98c 100644 > > --- a/lib/tpm_api.c > > +++ b/lib/tpm_api.c > > @@ -6,6 +6,7 @@ > > #include <common.h> > > #include <dm.h> > > #include <log.h> > > +#include <rng.h> > > #include <tpm_api.h> > > #include <tpm-v1.h> > > #include <tpm-v2.h> > > @@ -265,12 +266,26 @@ u32 tpm_get_permissions(struct udevice *dev, u32 index, u32 *perm) > > return -ENOSYS; > > } > > > > +#if CONFIG_IS_ENABLED(DM_RNG) > > int tpm_get_random(struct udevice *dev, void *data, u32 count) > > This is the function you should call My thinking was that the TPM drivers would use the tpm{1,2}_get_random functions directly, while tpm_get_random would be a generic API which could be called from any other module. This API would then call the driver model interface(dm_rng_read). But I see that you want this function to be called from the tpm rng driver. I have made the change in my v5. > > > { > > + int ret = -ENOSYS; > > + struct udevice *rng_dev; > > + > > if (tpm_is_v1(dev)) > > - return tpm1_get_random(dev, data, count); > > + ret = uclass_get_device_by_driver(UCLASS_RNG, > > + DM_DRIVER_GET(tpm1_rng), > > + &rng_dev); > > What is going on here? This code should stay the same. Why would you > go off and hunt for the device? > > > else if (tpm_is_v2(dev)) > > - return -ENOSYS; /* not implemented yet */ > > It is implemented above Yeah I know :). This is existing code which, for some reason, was not calling the tpm2_get_random function. I am fixing this now by removing this line. > > > - else > > - return -ENOSYS; > > + ret = uclass_get_device_by_driver(UCLASS_RNG, > > + DM_DRIVER_GET(tpm1_rng), > > + &rng_dev); > > + > > + if (ret) { > > + log_err("Getting tpm rng device failed\n"); > > + return ret; > > + } > > + > > + return dm_rng_read(rng_dev, data, (size_t)count); > > ?? Don't you want to call the TPM to get the random number? I am just lost. Please see the explanation above. -sughosh
diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile index 39f7ee3f03..c91e4e1701 100644 --- a/drivers/rng/Makefile +++ b/drivers/rng/Makefile @@ -10,3 +10,5 @@ obj-$(CONFIG_RNG_MSM) += msm_rng.o obj-$(CONFIG_RNG_STM32MP1) += stm32mp1_rng.o obj-$(CONFIG_RNG_ROCKCHIP) += rockchip_rng.o obj-$(CONFIG_RNG_IPROC200) += iproc_rng200.o +obj-$(CONFIG_TPM_V1) += tpm1_rng.o +obj-$(CONFIG_TPM_V2) += tpm2_rng.o diff --git a/drivers/rng/tpm1_rng.c b/drivers/rng/tpm1_rng.c new file mode 100644 index 0000000000..b827e2d1c1 --- /dev/null +++ b/drivers/rng/tpm1_rng.c @@ -0,0 +1,24 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2022, Linaro Limited + */ + +#include <dm.h> +#include <rng.h> +#include <tpm-v1.h> + +static int rng_tpm1_random_read(struct udevice *dev, void *data, size_t count) +{ + return tpm1_get_random(dev->parent, data, count); +} + +static const struct dm_rng_ops tpm1_rng_ops = { + .read = rng_tpm1_random_read, +}; + +U_BOOT_DRIVER(tpm1_rng) = { + .name = "tpm1-rng", + .id = UCLASS_RNG, + .ops = &tpm1_rng_ops, +}; + diff --git a/drivers/rng/tpm2_rng.c b/drivers/rng/tpm2_rng.c new file mode 100644 index 0000000000..bd1fd539f0 --- /dev/null +++ b/drivers/rng/tpm2_rng.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2022, Linaro Limited + */ + +#include <dm.h> +#include <rng.h> +#include <tpm-v2.h> + +static int rng_tpm2_random_read(struct udevice *dev, void *data, size_t count) +{ + return tpm2_get_random(dev->parent, data, count); +} + +static const struct dm_rng_ops tpm2_rng_ops = { + .read = rng_tpm2_random_read, +}; + +U_BOOT_DRIVER(tpm2_rng) = { + .name = "tpm2-rng", + .id = UCLASS_RNG, + .ops = &tpm2_rng_ops, +}; diff --git a/include/tpm-v1.h b/include/tpm-v1.h index 33d53fb695..d2ff8b446d 100644 --- a/include/tpm-v1.h +++ b/include/tpm-v1.h @@ -555,9 +555,9 @@ u32 tpm1_find_key_sha1(struct udevice *dev, const u8 auth[20], * @param dev TPM device * @param data output buffer for the random bytes * @param count size of output buffer - * Return: return code of the operation + * Return: 0 if OK, -ve on error */ -u32 tpm1_get_random(struct udevice *dev, void *data, u32 count); +int tpm1_get_random(struct udevice *dev, void *data, size_t count); /** * tpm_finalise_physical_presence() - Finalise physical presence diff --git a/include/tpm-v2.h b/include/tpm-v2.h index e79c90b939..4fb1e7a948 100644 --- a/include/tpm-v2.h +++ b/include/tpm-v2.h @@ -619,9 +619,9 @@ u32 tpm2_pcr_setauthvalue(struct udevice *dev, const char *pw, * @param data output buffer for the random bytes * @param count size of output buffer * - * Return: return code of the operation + * Return: 0 if OK, -ve on error */ -u32 tpm2_get_random(struct udevice *dev, void *data, u32 count); +int tpm2_get_random(struct udevice *dev, void *data, size_t count); /** * Lock data in the TPM diff --git a/lib/tpm-v1.c b/lib/tpm-v1.c index 22a769c587..4c6bc31a64 100644 --- a/lib/tpm-v1.c +++ b/lib/tpm-v1.c @@ -9,12 +9,14 @@ #include <common.h> #include <dm.h> #include <log.h> -#include <asm/unaligned.h> -#include <u-boot/sha1.h> +#include <rng.h> #include <tpm-common.h> #include <tpm-v1.h> #include "tpm-utils.h" +#include <asm/unaligned.h> +#include <u-boot/sha1.h> + #ifdef CONFIG_TPM_AUTH_SESSIONS #ifndef CONFIG_SHA1 @@ -869,7 +871,7 @@ u32 tpm1_find_key_sha1(struct udevice *dev, const u8 auth[20], #endif /* CONFIG_TPM_AUTH_SESSIONS */ -u32 tpm1_get_random(struct udevice *dev, void *data, u32 count) +int tpm1_get_random(struct udevice *dev, void *data, size_t count) { const u8 command[14] = { 0x0, 0xc1, /* TPM_TAG */ @@ -892,19 +894,19 @@ u32 tpm1_get_random(struct udevice *dev, void *data, u32 count) if (pack_byte_string(buf, sizeof(buf), "sd", 0, command, sizeof(command), length_offset, this_bytes)) - return TPM_LIB_ERROR; + return -EIO; err = tpm_sendrecv_command(dev, buf, response, &response_length); if (err) return err; if (unpack_byte_string(response, response_length, "d", data_size_offset, &data_size)) - return TPM_LIB_ERROR; + return -EIO; if (data_size > count) - return TPM_LIB_ERROR; + return -EIO; if (unpack_byte_string(response, response_length, "s", data_offset, out, data_size)) - return TPM_LIB_ERROR; + return -EIO; count -= data_size; out += data_size; diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c index 1bf627853a..d7a23ccf7e 100644 --- a/lib/tpm-v2.c +++ b/lib/tpm-v2.c @@ -6,6 +6,7 @@ #include <common.h> #include <dm.h> +#include <rng.h> #include <tpm-common.h> #include <tpm-v2.h> #include <linux/bitops.h> @@ -562,7 +563,7 @@ u32 tpm2_pcr_setauthvalue(struct udevice *dev, const char *pw, return tpm_sendrecv_command(dev, command_v2, NULL, NULL); } -u32 tpm2_get_random(struct udevice *dev, void *data, u32 count) +int tpm2_get_random(struct udevice *dev, void *data, size_t count) { const u8 command_v2[10] = { tpm_u16(TPM2_ST_NO_SESSIONS), @@ -585,19 +586,19 @@ u32 tpm2_get_random(struct udevice *dev, void *data, u32 count) if (pack_byte_string(buf, sizeof(buf), "sw", 0, command_v2, sizeof(command_v2), sizeof(command_v2), this_bytes)) - return TPM_LIB_ERROR; + return -EIO; err = tpm_sendrecv_command(dev, buf, response, &response_length); if (err) return err; if (unpack_byte_string(response, response_length, "w", data_size_offset, &data_size)) - return TPM_LIB_ERROR; + return -EIO; if (data_size > this_bytes) return TPM_LIB_ERROR; if (unpack_byte_string(response, response_length, "s", data_offset, out, data_size)) - return TPM_LIB_ERROR; + return -EIO; count -= data_size; out += data_size; diff --git a/lib/tpm_api.c b/lib/tpm_api.c index da48058abe..3584fda98c 100644 --- a/lib/tpm_api.c +++ b/lib/tpm_api.c @@ -6,6 +6,7 @@ #include <common.h> #include <dm.h> #include <log.h> +#include <rng.h> #include <tpm_api.h> #include <tpm-v1.h> #include <tpm-v2.h> @@ -265,12 +266,26 @@ u32 tpm_get_permissions(struct udevice *dev, u32 index, u32 *perm) return -ENOSYS; } +#if CONFIG_IS_ENABLED(DM_RNG) int tpm_get_random(struct udevice *dev, void *data, u32 count) { + int ret = -ENOSYS; + struct udevice *rng_dev; + if (tpm_is_v1(dev)) - return tpm1_get_random(dev, data, count); + ret = uclass_get_device_by_driver(UCLASS_RNG, + DM_DRIVER_GET(tpm1_rng), + &rng_dev); else if (tpm_is_v2(dev)) - return -ENOSYS; /* not implemented yet */ - else - return -ENOSYS; + ret = uclass_get_device_by_driver(UCLASS_RNG, + DM_DRIVER_GET(tpm1_rng), + &rng_dev); + + if (ret) { + log_err("Getting tpm rng device failed\n"); + return ret; + } + + return dm_rng_read(rng_dev, data, (size_t)count); } +#endif /* DM_RNG */
The TPM device has a builtin random number generator(RNG) functionality. Expose the RNG functions of the TPM device to the driver model so that they can be used by the EFI_RNG_PROTOCOL if the protocol is installed. Also change the function arguments and return type of the random number functions to comply with the driver model api. Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> --- Changes since V3: * Move back the driver model interface for the TPM RNG devices under drivers/rng/ directory. * Add a rng read function for the tpm devices which calls the tpm*_get_random API's. * Pass the TPM device pointer to the tpm*_get_random API's from the TPM RNG drivers as suggested by Simon. drivers/rng/Makefile | 2 ++ drivers/rng/tpm1_rng.c | 24 ++++++++++++++++++++++++ drivers/rng/tpm2_rng.c | 23 +++++++++++++++++++++++ include/tpm-v1.h | 4 ++-- include/tpm-v2.h | 4 ++-- lib/tpm-v1.c | 16 +++++++++------- lib/tpm-v2.c | 9 +++++---- lib/tpm_api.c | 23 +++++++++++++++++++---- 8 files changed, 86 insertions(+), 19 deletions(-) create mode 100644 drivers/rng/tpm1_rng.c create mode 100644 drivers/rng/tpm2_rng.c