| Message ID | 20210225203229.363302-2-patrick@puiterwijk.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Load keys from TPM2 NV Index on IMA keyring | expand |
On 2/25/21 3:32 PM, Patrick Uiterwijk wrote: > Add support to read contents from a TPM2 Non-Volatile Index location, > allowing the kernel to retrieve contents and attributes of NV indexes. > > Signed-off-by: Patrick Uiterwijk <patrick@puiterwijk.org> > --- > drivers/char/tpm/tpm-interface.c | 30 ++++++ > drivers/char/tpm/tpm.h | 5 + > drivers/char/tpm/tpm2-cmd.c | 163 +++++++++++++++++++++++++++++++ > include/linux/tpm.h | 65 ++++++++++++ > 4 files changed, 263 insertions(+) > > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c > index 1621ce818705..9d81c11181d4 100644 > --- a/drivers/char/tpm/tpm-interface.c > +++ b/drivers/char/tpm/tpm-interface.c > @@ -342,6 +342,36 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, > } > EXPORT_SYMBOL_GPL(tpm_pcr_extend); > > +/** > + * tpm_nv_read - Read an NV Index from the TPM > + * @chip: A &struct tpm_chip instance, %NULL for the default chip > + * @nv_idx: The NV Index to be retrieved > + * @attr_out: A place to store returned attributes if a TPM 2 was used > + * @out: A pointer where to store the return buffer > + * > + * Return: number of bytes read or a negative error value > + */ > +int tpm_nv_read(struct tpm_chip *chip, u32 nv_idx, u32 *attr_out, void **out) > +{ > + int rc; > + > + chip = tpm_find_get_ops(chip); > + if (!chip) > + return -ENODEV; > + > + if (chip->flags & TPM_CHIP_FLAG_TPM2) { > + rc = tpm2_nv_read(chip, nv_idx, attr_out, out); > + goto out; > + } > + > + rc = -ENODEV; > + > +out: > + tpm_put_ops(chip); > + return rc; > +} > +EXPORT_SYMBOL_GPL(tpm_nv_read); > + > /** > * tpm_send - send a TPM command > * @chip: a &struct tpm_chip instance, %NULL for the default chip > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h > index 947d1db0a5cc..d4dfc5148adb 100644 > --- a/drivers/char/tpm/tpm.h > +++ b/drivers/char/tpm/tpm.h > @@ -56,9 +56,12 @@ enum tpm_addr { > #define TPM_ERR_DEACTIVATED 0x6 > #define TPM_ERR_DISABLED 0x7 > #define TPM_ERR_INVALID_POSTINIT 38 > +#define TPM_ERR_INVALID_HANDLE_1 0x18b > > #define TPM_TAG_RQU_COMMAND 193 > > +#define TPM2_HR_NV_INDEX 0x1000000 > + > /* TPM2 specific constants. */ > #define TPM2_SPACE_BUFFER_SIZE 16384 /* 16 kB */ > > @@ -224,6 +227,8 @@ 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); > > +int tpm2_nv_read(struct tpm_chip *chip, u32 nvindex, u32 *attr_out, void **dest); > +int tpm2_nv_readpublic(struct tpm_chip *chip, u32 nvindex, struct tpm2_nv_public *info); > ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip); > int tpm2_auto_startup(struct tpm_chip *chip); > void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type); > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c > index eff1f12d981a..ba1026123464 100644 > --- a/drivers/char/tpm/tpm2-cmd.c > +++ b/drivers/char/tpm/tpm2-cmd.c > @@ -269,6 +269,169 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, > return rc; > } > > +struct tpm2_buffer_out { > + __be16 size; > + u8 data[]; > +} __packed; > + > +struct tpm2_nv_public_out { > + __be32 nvIndex; > + __be16 nameAlg; > + __be32 attributes; > + __be16 authPolicySize; > + u8 data[]; > +} __packed; > + > +int tpm2_nv_readpublic(struct tpm_chip *chip, u32 nvindex, struct tpm2_nv_public *info) > +{ > + struct tpm_buf buf; > + int rc; > + u16 recd; > + u32 resp_header_length; > + struct tpm2_buffer_out *out; > + struct tpm2_nv_public_out *publicout; > + u32 nvhandle; > + u16 auth_policy_size; > + > + if ((nvindex & ~TPM2_HR_NV_INDEX) > 0x00FFFFFF) > + return -EINVAL; > + > + /* HR_NV_INDEX = TPM_HT_NV_INDEX << HR_SHIFT */ > + nvhandle = TPM2_HR_NV_INDEX | nvindex; > + > + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_NV_READPUBLIC); > + if (rc) > + return rc; > + tpm_buf_append_u32(&buf, nvhandle); > + rc = tpm_transmit_cmd(chip, &buf, 0, NULL); > + if (rc) { > + if (rc != TPM_ERR_DISABLED && rc != TPM_ERR_DEACTIVATED These are TPM 1.2 error codes. I don't think TPM 2 returns those, does it? Ah, you took that from tpm_transmit_cmd... I think you can remove those. > + && rc != TPM2_RC_TESTING && rc != TPM_ERR_INVALID_HANDLE_1) > + dev_err(&chip->dev, "A TPM error (%d) occurred attempting to read an NV Index public\n", rc); > + if (rc == TPM_ERR_INVALID_HANDLE_1) > + rc = -ENOENT; > + else if (rc > 0) > + rc = -EIO; > + goto out; > + } > + resp_header_length = tpm_buf_response_header_length(&buf, 0); > + out = (struct tpm2_buffer_out *)&buf.data[resp_header_length]; > + publicout = (struct tpm2_nv_public_out *)&out->data; > + recd = be16_to_cpu(out->size); > + > + info->nv_index = be32_to_cpu(publicout->nvIndex); > + info->name_alg = be16_to_cpu(publicout->nameAlg); > + info->attributes = be32_to_cpu(publicout->attributes); > + > + /* Determine the size of the authPolicy, so we can skip over that to grab the data size */ > + auth_policy_size = be16_to_cpu(publicout->authPolicySize); > + > + info->data_size = be16_to_cpu((publicout->data[auth_policy_size]) | (publicout->data[auth_policy_size+1] << 8)); I don't think this is correct. The way you read the 2 bytes they are already in native format then due to the shifting. So be16_to_cpu should return the wrong result on little endian machines. > + > +out: > + tpm_buf_destroy(&buf); > + return rc; > +} > + > +int tpm2_nv_read(struct tpm_chip *chip, u32 nvindex, u32 *attr_out, void **dest) > +{ > + struct tpm_buf buf; > + int rc; > + struct tpm2_buffer_out *out; > + u16 recd; > + u16 copied; > + u32 nvhandle; > + u32 resp_header_length; > + struct tpm2_null_auth_area auth_area; > + u16 size; > + struct tpm2_nv_public public; > + > + copied = 0; > + > + if ((nvindex & ~TPM2_HR_NV_INDEX) > 0x00FFFFFF) > + return -EINVAL; > + > + /* HR_NV_INDEX = TPM_HT_NV_INDEX << HR_SHIFT */ > + nvhandle = TPM2_HR_NV_INDEX | nvindex; > + > + /* Determine the size of the NV Index contents */ > + rc = tpm2_nv_readpublic(chip, nvindex, &public); > + if (rc < 0) > + return rc; > + if (attr_out != NULL) > + *attr_out = public.attributes; > + size = public.data_size; > + *dest = kzalloc(size, GFP_KERNEL); > + if (!*dest) { > + rc = -ENOMEM; > + goto out; > + } > + > + /* Retrieve the actual NV Index contents */ > + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_NV_READ); > + if (rc) > + goto out_free; > + > + while (copied < size) { > + tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_NV_READ); > + > + tpm_buf_append_u32(&buf, TPM2_RH_OWNER); > + tpm_buf_append_u32(&buf, nvhandle); > + > + auth_area.handle = cpu_to_be32(TPM2_RS_PW); > + auth_area.nonce_size = 0; > + auth_area.attributes = 0; > + auth_area.auth_size = 0; > + > + tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area)); > + tpm_buf_append(&buf, (const unsigned char *)&auth_area, > + sizeof(auth_area)); > + > + /* Size to request: at most 512 bytes at a time */ > + tpm_buf_append_u16(&buf, min_t(u16, 512, size-copied)); > + /* Offset: start at where we ended up */ > + tpm_buf_append_u16(&buf, copied); > + > + rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read NV index"); > + if (rc) { > + if (rc > 0) > + rc = -EIO; > + goto out_free; > + } > + resp_header_length = tpm_buf_response_header_length(&buf, 0); > + out = (struct tpm2_buffer_out *)&buf.data[resp_header_length]; > + recd = be16_to_cpu(out->size); > + > + if (recd == 0) { > + rc = -EIO; > + goto out_free; > + } > + if (recd > size-copied) { > + rc = -EIO; > + goto out_free; > + } You could add this to the above. if (recd == 0 || recd > size - copied) ... This address the case where the TPM is actually returning more bytes than requested. > + > + memcpy(*dest + copied, out->data, recd); > + copied += recd; > + }; > + > +out_free: > + if ((rc < 0) || (copied != size)) { > + kvfree(*dest); kfree ? > + *dest = NULL; > + } > + > +out: > + tpm_buf_destroy(&buf); > + > + if (rc < 0) > + return rc; > + else if (copied != size) > + return -EIO; > + else > + return size; > +} > + > struct tpm2_get_random_out { > __be16 size; > u8 buffer[TPM_MAX_RNG_DATA]; > diff --git a/include/linux/tpm.h b/include/linux/tpm.h > index 8f4ff39f51e7..b812236b9955 100644 > --- a/include/linux/tpm.h > +++ b/include/linux/tpm.h > @@ -53,6 +53,40 @@ struct tpm_bank_info { > u16 crypto_id; > }; > > +enum tpm_nv_public_attrs { > + TPM2_ATTR_NV_PPWRITE = 0x00000001, > + TPM2_ATTR_NV_OWNERWRITE = 0x00000002, > + TPM2_ATTR_NV_AUTHWRITE = 0x00000004, > + TPM2_ATTR_NV_POLICYWRITE = 0x00000008, > + /* Bits 4-7 TPM_NT */ > + /* Bits 8-9 reserved */ > + TPM2_ATTR_NV_POLICY_DELETE = 0x00000400, > + TPM2_ATTR_NV_WRITELOCKED = 0x00000800, > + TPM2_ATTR_NV_WRITEALL = 0x00001000, > + TPM2_ATTR_NV_WRITE_DEFINE = 0x00002000, > + TPM2_ATTR_NV_WRITE_STCLEAR = 0x00004000, > + TPM2_ATTR_NV_GLOBALLOCK = 0x00008000, > + TPM2_ATTR_NV_PPREAD = 0x00010000, > + TPM2_ATTR_NV_OWNERREAD = 0x00020000, > + TPM2_ATTR_NV_AUTHREAD = 0x00040000, > + TPM2_ATTR_NV_POLICYREAD = 0x00080000, > + /* Bits 20-24 reserved */ > + TPM2_ATTR_NV_NO_DA = 0x02000000, > + TPM2_ATTR_NV_ORDERLY = 0x04000000, > + TPM2_ATTR_NV_CLEAR_STCLEAR = 0x08000000, > + TPM2_ATTR_NV_READLOCKED = 0x10000000, > + TPM2_ATTR_NV_WRITTEN = 0x20000000, > + TPM2_ATTR_NV_PLATFORMCREATE = 0x40000000, > + TPM2_ATTR_NV_READ_STCLEAR = 0x80000000, > +}; > + > +struct tpm2_nv_public { > + u32 nv_index; > + u16 name_alg; > + u32 attributes; > + u16 data_size; > +}; > + > enum TPM_OPS_FLAGS { > TPM_OPS_AUTO_STARTUP = BIT(0), > }; > @@ -189,6 +223,10 @@ enum tpm2_structures { > TPM2_ST_SESSIONS = 0x8002, > }; > > +enum tpm2_root_handles { > + TPM2_RH_OWNER = 0x40000001, > +}; > + > /* Indicates from what layer of the software stack the error comes from */ > #define TSS2_RC_LAYER_SHIFT 16 > #define TSS2_RESMGR_TPM_RC_LAYER (11 << TSS2_RC_LAYER_SHIFT) > @@ -223,6 +261,7 @@ enum tpm2_command_codes { > TPM2_CC_CONTEXT_LOAD = 0x0161, > TPM2_CC_CONTEXT_SAVE = 0x0162, > TPM2_CC_FLUSH_CONTEXT = 0x0165, > + TPM2_CC_NV_READPUBLIC = 0x0169, > TPM2_CC_VERIFY_SIGNATURE = 0x0177, > TPM2_CC_GET_CAPABILITY = 0x017A, > TPM2_CC_GET_RANDOM = 0x017B, > @@ -389,6 +428,21 @@ static inline void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value) > tpm_buf_append(buf, (u8 *) &value2, 4); > } > > +static inline u32 tpm_buf_response_header_length(struct tpm_buf *buf, bool has_shielded_locations) > +{ > + u32 header_length = TPM_HEADER_SIZE; > + > + /* Possibly a handle for a Shielded Location */ > + if (has_shielded_locations) > + header_length += 4; > + > + /* Possibly the 32-bit parameter area size */ > + if (tpm_buf_tag(buf) == TPM2_ST_SESSIONS) > + header_length += 4; > + > + return header_length; > +} > + > static inline u32 tpm2_rc_value(u32 rc) > { > return (rc & BIT(7)) ? rc & 0xff : rc; > @@ -401,6 +455,7 @@ extern int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx, > struct tpm_digest *digest); > extern int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, > struct tpm_digest *digests); > +extern int tpm_nv_read(struct tpm_chip *chip, u32 nv_idx, u32 *attrs_out, void **out); > extern int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen); > extern int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max); > extern struct tpm_chip *tpm_default_chip(void); > @@ -423,6 +478,16 @@ static inline int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, > return -ENODEV; > } > > +static inline int tpm2_nv_readpublic(struct tpm_chip *chip, u32 nvindex, struct tpm2_nv_public *info) > +{ > + return -ENODEV; > +} > + > +static inline int tpm_nv_read(struct tpm_chip *chip, u32 nv_idx, u8 *out, size_t max) > +{ tpm2_nv_read > + return -ENODEV; > +} > + > static inline int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen) > { > return -ENODEV;
On Thu, Feb 25, 2021 at 09:32:27PM +0100, Patrick Uiterwijk wrote: > Add support to read contents from a TPM2 Non-Volatile Index location, > allowing the kernel to retrieve contents and attributes of NV indexes. > > Signed-off-by: Patrick Uiterwijk <patrick@puiterwijk.org> How many call sites? /Jarkko
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 1621ce818705..9d81c11181d4 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -342,6 +342,36 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, } EXPORT_SYMBOL_GPL(tpm_pcr_extend); +/** + * tpm_nv_read - Read an NV Index from the TPM + * @chip: A &struct tpm_chip instance, %NULL for the default chip + * @nv_idx: The NV Index to be retrieved + * @attr_out: A place to store returned attributes if a TPM 2 was used + * @out: A pointer where to store the return buffer + * + * Return: number of bytes read or a negative error value + */ +int tpm_nv_read(struct tpm_chip *chip, u32 nv_idx, u32 *attr_out, void **out) +{ + int rc; + + chip = tpm_find_get_ops(chip); + if (!chip) + return -ENODEV; + + if (chip->flags & TPM_CHIP_FLAG_TPM2) { + rc = tpm2_nv_read(chip, nv_idx, attr_out, out); + goto out; + } + + rc = -ENODEV; + +out: + tpm_put_ops(chip); + return rc; +} +EXPORT_SYMBOL_GPL(tpm_nv_read); + /** * tpm_send - send a TPM command * @chip: a &struct tpm_chip instance, %NULL for the default chip diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 947d1db0a5cc..d4dfc5148adb 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -56,9 +56,12 @@ enum tpm_addr { #define TPM_ERR_DEACTIVATED 0x6 #define TPM_ERR_DISABLED 0x7 #define TPM_ERR_INVALID_POSTINIT 38 +#define TPM_ERR_INVALID_HANDLE_1 0x18b #define TPM_TAG_RQU_COMMAND 193 +#define TPM2_HR_NV_INDEX 0x1000000 + /* TPM2 specific constants. */ #define TPM2_SPACE_BUFFER_SIZE 16384 /* 16 kB */ @@ -224,6 +227,8 @@ 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); +int tpm2_nv_read(struct tpm_chip *chip, u32 nvindex, u32 *attr_out, void **dest); +int tpm2_nv_readpublic(struct tpm_chip *chip, u32 nvindex, struct tpm2_nv_public *info); ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip); int tpm2_auto_startup(struct tpm_chip *chip); void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type); diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index eff1f12d981a..ba1026123464 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -269,6 +269,169 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, return rc; } +struct tpm2_buffer_out { + __be16 size; + u8 data[]; +} __packed; + +struct tpm2_nv_public_out { + __be32 nvIndex; + __be16 nameAlg; + __be32 attributes; + __be16 authPolicySize; + u8 data[]; +} __packed; + +int tpm2_nv_readpublic(struct tpm_chip *chip, u32 nvindex, struct tpm2_nv_public *info) +{ + struct tpm_buf buf; + int rc; + u16 recd; + u32 resp_header_length; + struct tpm2_buffer_out *out; + struct tpm2_nv_public_out *publicout; + u32 nvhandle; + u16 auth_policy_size; + + if ((nvindex & ~TPM2_HR_NV_INDEX) > 0x00FFFFFF) + return -EINVAL; + + /* HR_NV_INDEX = TPM_HT_NV_INDEX << HR_SHIFT */ + nvhandle = TPM2_HR_NV_INDEX | nvindex; + + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_NV_READPUBLIC); + if (rc) + return rc; + tpm_buf_append_u32(&buf, nvhandle); + rc = tpm_transmit_cmd(chip, &buf, 0, NULL); + if (rc) { + if (rc != TPM_ERR_DISABLED && rc != TPM_ERR_DEACTIVATED + && rc != TPM2_RC_TESTING && rc != TPM_ERR_INVALID_HANDLE_1) + dev_err(&chip->dev, "A TPM error (%d) occurred attempting to read an NV Index public\n", rc); + if (rc == TPM_ERR_INVALID_HANDLE_1) + rc = -ENOENT; + else if (rc > 0) + rc = -EIO; + goto out; + } + resp_header_length = tpm_buf_response_header_length(&buf, 0); + out = (struct tpm2_buffer_out *)&buf.data[resp_header_length]; + publicout = (struct tpm2_nv_public_out *)&out->data; + recd = be16_to_cpu(out->size); + + info->nv_index = be32_to_cpu(publicout->nvIndex); + info->name_alg = be16_to_cpu(publicout->nameAlg); + info->attributes = be32_to_cpu(publicout->attributes); + + /* Determine the size of the authPolicy, so we can skip over that to grab the data size */ + auth_policy_size = be16_to_cpu(publicout->authPolicySize); + + info->data_size = be16_to_cpu((publicout->data[auth_policy_size]) | (publicout->data[auth_policy_size+1] << 8)); + +out: + tpm_buf_destroy(&buf); + return rc; +} + +int tpm2_nv_read(struct tpm_chip *chip, u32 nvindex, u32 *attr_out, void **dest) +{ + struct tpm_buf buf; + int rc; + struct tpm2_buffer_out *out; + u16 recd; + u16 copied; + u32 nvhandle; + u32 resp_header_length; + struct tpm2_null_auth_area auth_area; + u16 size; + struct tpm2_nv_public public; + + copied = 0; + + if ((nvindex & ~TPM2_HR_NV_INDEX) > 0x00FFFFFF) + return -EINVAL; + + /* HR_NV_INDEX = TPM_HT_NV_INDEX << HR_SHIFT */ + nvhandle = TPM2_HR_NV_INDEX | nvindex; + + /* Determine the size of the NV Index contents */ + rc = tpm2_nv_readpublic(chip, nvindex, &public); + if (rc < 0) + return rc; + if (attr_out != NULL) + *attr_out = public.attributes; + size = public.data_size; + *dest = kzalloc(size, GFP_KERNEL); + if (!*dest) { + rc = -ENOMEM; + goto out; + } + + /* Retrieve the actual NV Index contents */ + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_NV_READ); + if (rc) + goto out_free; + + while (copied < size) { + tpm_buf_reset(&buf, TPM2_ST_SESSIONS, TPM2_CC_NV_READ); + + tpm_buf_append_u32(&buf, TPM2_RH_OWNER); + tpm_buf_append_u32(&buf, nvhandle); + + auth_area.handle = cpu_to_be32(TPM2_RS_PW); + auth_area.nonce_size = 0; + auth_area.attributes = 0; + auth_area.auth_size = 0; + + tpm_buf_append_u32(&buf, sizeof(struct tpm2_null_auth_area)); + tpm_buf_append(&buf, (const unsigned char *)&auth_area, + sizeof(auth_area)); + + /* Size to request: at most 512 bytes at a time */ + tpm_buf_append_u16(&buf, min_t(u16, 512, size-copied)); + /* Offset: start at where we ended up */ + tpm_buf_append_u16(&buf, copied); + + rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to read NV index"); + if (rc) { + if (rc > 0) + rc = -EIO; + goto out_free; + } + resp_header_length = tpm_buf_response_header_length(&buf, 0); + out = (struct tpm2_buffer_out *)&buf.data[resp_header_length]; + recd = be16_to_cpu(out->size); + + if (recd == 0) { + rc = -EIO; + goto out_free; + } + if (recd > size-copied) { + rc = -EIO; + goto out_free; + } + + memcpy(*dest + copied, out->data, recd); + copied += recd; + }; + +out_free: + if ((rc < 0) || (copied != size)) { + kvfree(*dest); + *dest = NULL; + } + +out: + tpm_buf_destroy(&buf); + + if (rc < 0) + return rc; + else if (copied != size) + return -EIO; + else + return size; +} + struct tpm2_get_random_out { __be16 size; u8 buffer[TPM_MAX_RNG_DATA]; diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 8f4ff39f51e7..b812236b9955 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -53,6 +53,40 @@ struct tpm_bank_info { u16 crypto_id; }; +enum tpm_nv_public_attrs { + TPM2_ATTR_NV_PPWRITE = 0x00000001, + TPM2_ATTR_NV_OWNERWRITE = 0x00000002, + TPM2_ATTR_NV_AUTHWRITE = 0x00000004, + TPM2_ATTR_NV_POLICYWRITE = 0x00000008, + /* Bits 4-7 TPM_NT */ + /* Bits 8-9 reserved */ + TPM2_ATTR_NV_POLICY_DELETE = 0x00000400, + TPM2_ATTR_NV_WRITELOCKED = 0x00000800, + TPM2_ATTR_NV_WRITEALL = 0x00001000, + TPM2_ATTR_NV_WRITE_DEFINE = 0x00002000, + TPM2_ATTR_NV_WRITE_STCLEAR = 0x00004000, + TPM2_ATTR_NV_GLOBALLOCK = 0x00008000, + TPM2_ATTR_NV_PPREAD = 0x00010000, + TPM2_ATTR_NV_OWNERREAD = 0x00020000, + TPM2_ATTR_NV_AUTHREAD = 0x00040000, + TPM2_ATTR_NV_POLICYREAD = 0x00080000, + /* Bits 20-24 reserved */ + TPM2_ATTR_NV_NO_DA = 0x02000000, + TPM2_ATTR_NV_ORDERLY = 0x04000000, + TPM2_ATTR_NV_CLEAR_STCLEAR = 0x08000000, + TPM2_ATTR_NV_READLOCKED = 0x10000000, + TPM2_ATTR_NV_WRITTEN = 0x20000000, + TPM2_ATTR_NV_PLATFORMCREATE = 0x40000000, + TPM2_ATTR_NV_READ_STCLEAR = 0x80000000, +}; + +struct tpm2_nv_public { + u32 nv_index; + u16 name_alg; + u32 attributes; + u16 data_size; +}; + enum TPM_OPS_FLAGS { TPM_OPS_AUTO_STARTUP = BIT(0), }; @@ -189,6 +223,10 @@ enum tpm2_structures { TPM2_ST_SESSIONS = 0x8002, }; +enum tpm2_root_handles { + TPM2_RH_OWNER = 0x40000001, +}; + /* Indicates from what layer of the software stack the error comes from */ #define TSS2_RC_LAYER_SHIFT 16 #define TSS2_RESMGR_TPM_RC_LAYER (11 << TSS2_RC_LAYER_SHIFT) @@ -223,6 +261,7 @@ enum tpm2_command_codes { TPM2_CC_CONTEXT_LOAD = 0x0161, TPM2_CC_CONTEXT_SAVE = 0x0162, TPM2_CC_FLUSH_CONTEXT = 0x0165, + TPM2_CC_NV_READPUBLIC = 0x0169, TPM2_CC_VERIFY_SIGNATURE = 0x0177, TPM2_CC_GET_CAPABILITY = 0x017A, TPM2_CC_GET_RANDOM = 0x017B, @@ -389,6 +428,21 @@ static inline void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value) tpm_buf_append(buf, (u8 *) &value2, 4); } +static inline u32 tpm_buf_response_header_length(struct tpm_buf *buf, bool has_shielded_locations) +{ + u32 header_length = TPM_HEADER_SIZE; + + /* Possibly a handle for a Shielded Location */ + if (has_shielded_locations) + header_length += 4; + + /* Possibly the 32-bit parameter area size */ + if (tpm_buf_tag(buf) == TPM2_ST_SESSIONS) + header_length += 4; + + return header_length; +} + static inline u32 tpm2_rc_value(u32 rc) { return (rc & BIT(7)) ? rc & 0xff : rc; @@ -401,6 +455,7 @@ extern int tpm_pcr_read(struct tpm_chip *chip, u32 pcr_idx, struct tpm_digest *digest); extern int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, struct tpm_digest *digests); +extern int tpm_nv_read(struct tpm_chip *chip, u32 nv_idx, u32 *attrs_out, void **out); extern int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen); extern int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max); extern struct tpm_chip *tpm_default_chip(void); @@ -423,6 +478,16 @@ static inline int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, return -ENODEV; } +static inline int tpm2_nv_readpublic(struct tpm_chip *chip, u32 nvindex, struct tpm2_nv_public *info) +{ + return -ENODEV; +} + +static inline int tpm_nv_read(struct tpm_chip *chip, u32 nv_idx, u8 *out, size_t max) +{ + return -ENODEV; +} + static inline int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen) { return -ENODEV;
Add support to read contents from a TPM2 Non-Volatile Index location, allowing the kernel to retrieve contents and attributes of NV indexes. Signed-off-by: Patrick Uiterwijk <patrick@puiterwijk.org> --- drivers/char/tpm/tpm-interface.c | 30 ++++++ drivers/char/tpm/tpm.h | 5 + drivers/char/tpm/tpm2-cmd.c | 163 +++++++++++++++++++++++++++++++ include/linux/tpm.h | 65 ++++++++++++ 4 files changed, 263 insertions(+)