Move TPM2 trusted keys code to trusted keys subsystem.
Suggested-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com Signed-off-by: Sumit Garg sumit.garg@linaro.org --- drivers/char/tpm/tpm-interface.c | 56 ----- drivers/char/tpm/tpm.h | 224 ------------------ drivers/char/tpm/tpm2-cmd.c | 307 ------------------------ include/keys/trusted_tpm.h | 23 +- include/linux/tpm.h | 264 +++++++++++++++++++-- security/keys/trusted-keys/Makefile | 3 +- security/keys/trusted-keys/trusted-tpm.c | 16 +- security/keys/trusted-keys/trusted-tpm2.c | 378 ++++++++++++++++++++++++++++++ 8 files changed, 652 insertions(+), 619 deletions(-) create mode 100644 security/keys/trusted-keys/trusted-tpm2.c
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 1b4f95c..208e5ba 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -454,62 +454,6 @@ int tpm_get_random(struct tpm_chip *chip, u8 *out, size_t max) } EXPORT_SYMBOL_GPL(tpm_get_random);
-/** - * tpm_seal_trusted() - seal a trusted key payload - * @chip: a &struct tpm_chip instance, %NULL for the default chip - * @options: authentication values and other options - * @payload: the key data in clear and encrypted form - * - * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in - * the keyring subsystem. - * - * Return: same as with tpm_transmit_cmd() - */ -int tpm_seal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, - struct trusted_key_options *options) -{ - int rc; - - chip = tpm_find_get_ops(chip); - if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2)) - return -ENODEV; - - rc = tpm2_seal_trusted(chip, payload, options); - - tpm_put_ops(chip); - return rc; -} -EXPORT_SYMBOL_GPL(tpm_seal_trusted); - -/** - * tpm_unseal_trusted() - unseal a trusted key - * @chip: a &struct tpm_chip instance, %NULL for the default chip - * @options: authentication values and other options - * @payload: the key data in clear and encrypted form - * - * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in - * the keyring subsystem. - * - * Return: same as with tpm_transmit_cmd() - */ -int tpm_unseal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options) -{ - int rc; - - chip = tpm_find_get_ops(chip); - if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2)) - return -ENODEV; - - rc = tpm2_unseal_trusted(chip, payload, options); - - tpm_put_ops(chip); - - return rc; -} -EXPORT_SYMBOL_GPL(tpm_unseal_trusted); - static int __init tpm_init(void) { int rc; diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index e503ffc..0705d44 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -25,7 +25,6 @@ #include <linux/platform_device.h> #include <linux/io.h> #include <linux/tpm.h> -#include <linux/highmem.h> #include <linux/tpm_eventlog.h>
#ifdef CONFIG_X86 @@ -58,123 +57,12 @@ enum tpm_addr { #define TPM_ERR_DISABLED 0x7 #define TPM_ERR_INVALID_POSTINIT 38
-#define TPM_HEADER_SIZE 10 - -enum tpm2_const { - TPM2_PLATFORM_PCR = 24, - TPM2_PCR_SELECT_MIN = ((TPM2_PLATFORM_PCR + 7) / 8), -}; - -enum tpm2_timeouts { - TPM2_TIMEOUT_A = 750, - TPM2_TIMEOUT_B = 2000, - TPM2_TIMEOUT_C = 200, - TPM2_TIMEOUT_D = 30, - TPM2_DURATION_SHORT = 20, - TPM2_DURATION_MEDIUM = 750, - TPM2_DURATION_LONG = 2000, - TPM2_DURATION_LONG_LONG = 300000, - TPM2_DURATION_DEFAULT = 120000, -}; - -enum tpm2_structures { - TPM2_ST_NO_SESSIONS = 0x8001, - TPM2_ST_SESSIONS = 0x8002, -}; - -/* 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) - -enum tpm2_return_codes { - TPM2_RC_SUCCESS = 0x0000, - TPM2_RC_HASH = 0x0083, /* RC_FMT1 */ - TPM2_RC_HANDLE = 0x008B, - TPM2_RC_INITIALIZE = 0x0100, /* RC_VER1 */ - TPM2_RC_FAILURE = 0x0101, - TPM2_RC_DISABLED = 0x0120, - TPM2_RC_COMMAND_CODE = 0x0143, - TPM2_RC_TESTING = 0x090A, /* RC_WARN */ - TPM2_RC_REFERENCE_H0 = 0x0910, - TPM2_RC_RETRY = 0x0922, -}; - -enum tpm2_command_codes { - TPM2_CC_FIRST = 0x011F, - TPM2_CC_HIERARCHY_CONTROL = 0x0121, - TPM2_CC_HIERARCHY_CHANGE_AUTH = 0x0129, - TPM2_CC_CREATE_PRIMARY = 0x0131, - TPM2_CC_SEQUENCE_COMPLETE = 0x013E, - TPM2_CC_SELF_TEST = 0x0143, - TPM2_CC_STARTUP = 0x0144, - TPM2_CC_SHUTDOWN = 0x0145, - TPM2_CC_NV_READ = 0x014E, - TPM2_CC_CREATE = 0x0153, - TPM2_CC_LOAD = 0x0157, - TPM2_CC_SEQUENCE_UPDATE = 0x015C, - TPM2_CC_UNSEAL = 0x015E, - TPM2_CC_CONTEXT_LOAD = 0x0161, - TPM2_CC_CONTEXT_SAVE = 0x0162, - TPM2_CC_FLUSH_CONTEXT = 0x0165, - TPM2_CC_VERIFY_SIGNATURE = 0x0177, - TPM2_CC_GET_CAPABILITY = 0x017A, - TPM2_CC_GET_RANDOM = 0x017B, - TPM2_CC_PCR_READ = 0x017E, - TPM2_CC_PCR_EXTEND = 0x0182, - TPM2_CC_EVENT_SEQUENCE_COMPLETE = 0x0185, - TPM2_CC_HASH_SEQUENCE_START = 0x0186, - TPM2_CC_CREATE_LOADED = 0x0191, - TPM2_CC_LAST = 0x0193, /* Spec 1.36 */ -}; - -enum tpm2_permanent_handles { - TPM2_RS_PW = 0x40000009, -}; - -enum tpm2_capabilities { - TPM2_CAP_HANDLES = 1, - TPM2_CAP_COMMANDS = 2, - TPM2_CAP_PCRS = 5, - TPM2_CAP_TPM_PROPERTIES = 6, -}; - -enum tpm2_properties { - TPM_PT_TOTAL_COMMANDS = 0x0129, -}; - -enum tpm2_startup_types { - TPM2_SU_CLEAR = 0x0000, - TPM2_SU_STATE = 0x0001, -}; - -enum tpm2_cc_attrs { - TPM2_CC_ATTR_CHANDLES = 25, - TPM2_CC_ATTR_RHANDLE = 28, -}; - #define TPM_VID_INTEL 0x8086 #define TPM_VID_WINBOND 0x1050 #define TPM_VID_STM 0x104A
-enum tpm_chip_flags { - TPM_CHIP_FLAG_TPM2 = BIT(1), - TPM_CHIP_FLAG_IRQ = BIT(2), - TPM_CHIP_FLAG_VIRTUAL = BIT(3), - TPM_CHIP_FLAG_HAVE_TIMEOUTS = BIT(4), - TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5), -}; - #define to_tpm_chip(d) container_of(d, struct tpm_chip, dev)
-struct tpm_header { - __be16 tag; - __be32 length; - union { - __be32 ordinal; - __be32 return_code; - }; -} __packed; - #define TPM_TAG_RQU_COMMAND 193
struct stclear_flags_t { @@ -274,102 +162,6 @@ enum tpm_sub_capabilities { * compiler warnings about stack frame size. */ #define TPM_MAX_RNG_DATA 128
-/* A string buffer type for constructing TPM commands. This is based on the - * ideas of string buffer code in security/keys/trusted.h but is heap based - * in order to keep the stack usage minimal. - */ - -enum tpm_buf_flags { - TPM_BUF_OVERFLOW = BIT(0), -}; - -struct tpm_buf { - struct page *data_page; - unsigned int flags; - u8 *data; -}; - -static inline void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal) -{ - struct tpm_header *head = (struct tpm_header *)buf->data; - - head->tag = cpu_to_be16(tag); - head->length = cpu_to_be32(sizeof(*head)); - head->ordinal = cpu_to_be32(ordinal); -} - -static inline int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal) -{ - buf->data_page = alloc_page(GFP_HIGHUSER); - if (!buf->data_page) - return -ENOMEM; - - buf->flags = 0; - buf->data = kmap(buf->data_page); - tpm_buf_reset(buf, tag, ordinal); - return 0; -} - -static inline void tpm_buf_destroy(struct tpm_buf *buf) -{ - kunmap(buf->data_page); - __free_page(buf->data_page); -} - -static inline u32 tpm_buf_length(struct tpm_buf *buf) -{ - struct tpm_header *head = (struct tpm_header *)buf->data; - - return be32_to_cpu(head->length); -} - -static inline u16 tpm_buf_tag(struct tpm_buf *buf) -{ - struct tpm_header *head = (struct tpm_header *)buf->data; - - return be16_to_cpu(head->tag); -} - -static inline void tpm_buf_append(struct tpm_buf *buf, - const unsigned char *new_data, - unsigned int new_len) -{ - struct tpm_header *head = (struct tpm_header *)buf->data; - u32 len = tpm_buf_length(buf); - - /* Return silently if overflow has already happened. */ - if (buf->flags & TPM_BUF_OVERFLOW) - return; - - if ((len + new_len) > PAGE_SIZE) { - WARN(1, "tpm_buf: overflow\n"); - buf->flags |= TPM_BUF_OVERFLOW; - return; - } - - memcpy(&buf->data[len], new_data, new_len); - head->length = cpu_to_be32(len + new_len); -} - -static inline void tpm_buf_append_u8(struct tpm_buf *buf, const u8 value) -{ - tpm_buf_append(buf, &value, 1); -} - -static inline void tpm_buf_append_u16(struct tpm_buf *buf, const u16 value) -{ - __be16 value2 = cpu_to_be16(value); - - tpm_buf_append(buf, (u8 *) &value2, 2); -} - -static inline void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value) -{ - __be32 value2 = cpu_to_be32(value); - - tpm_buf_append(buf, (u8 *) &value2, 4); -} - extern struct class *tpm_class; extern struct class *tpmrm_class; extern dev_t tpm_devt; @@ -378,8 +170,6 @@ extern const struct file_operations tpmrm_fops; extern struct idr dev_nums_idr;
ssize_t tpm_transmit(struct tpm_chip *chip, u8 *buf, size_t bufsiz); -ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf, - size_t min_rsp_body_length, const char *desc); int tpm_get_timeouts(struct tpm_chip *); int tpm_auto_startup(struct tpm_chip *chip);
@@ -406,9 +196,7 @@ static inline void tpm_msleep(unsigned int delay_msec)
int tpm_chip_start(struct tpm_chip *chip); void tpm_chip_stop(struct tpm_chip *chip); -struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip); __must_check int tpm_try_get_ops(struct tpm_chip *chip); -void tpm_put_ops(struct tpm_chip *chip);
struct tpm_chip *tpm_chip_alloc(struct device *dev, const struct tpm_class_ops *ops); @@ -428,24 +216,12 @@ static inline void tpm_add_ppi(struct tpm_chip *chip) } #endif
-static inline u32 tpm2_rc_value(u32 rc) -{ - return (rc & BIT(7)) ? rc & 0xff : rc; -} - int tpm2_get_timeouts(struct tpm_chip *chip); 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); -void tpm2_flush_context(struct tpm_chip *chip, u32 handle); -int tpm2_seal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options); -int tpm2_unseal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options); ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id, u32 *value, const char *desc);
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index d103545..0a319e1 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -13,20 +13,6 @@
#include "tpm.h" #include <crypto/hash_info.h> -#include <keys/trusted-type.h> - -enum tpm2_object_attributes { - TPM2_OA_USER_WITH_AUTH = BIT(6), -}; - -enum tpm2_session_attributes { - TPM2_SA_CONTINUE_SESSION = BIT(0), -}; - -struct tpm2_hash { - unsigned int crypto_id; - unsigned int tpm_id; -};
static struct tpm2_hash tpm2_hash_map[] = { {HASH_ALGO_SHA1, TPM_ALG_SHA1}, @@ -377,299 +363,6 @@ void tpm2_flush_context(struct tpm_chip *chip, u32 handle) tpm_buf_destroy(&buf); }
-/** - * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer. - * - * @buf: an allocated tpm_buf instance - * @session_handle: session handle - * @nonce: the session nonce, may be NULL if not used - * @nonce_len: the session nonce length, may be 0 if not used - * @attributes: the session attributes - * @hmac: the session HMAC or password, may be NULL if not used - * @hmac_len: the session HMAC or password length, maybe 0 if not used - */ -static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle, - const u8 *nonce, u16 nonce_len, - u8 attributes, - const u8 *hmac, u16 hmac_len) -{ - tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len); - tpm_buf_append_u32(buf, session_handle); - tpm_buf_append_u16(buf, nonce_len); - - if (nonce && nonce_len) - tpm_buf_append(buf, nonce, nonce_len); - - tpm_buf_append_u8(buf, attributes); - tpm_buf_append_u16(buf, hmac_len); - - if (hmac && hmac_len) - tpm_buf_append(buf, hmac, hmac_len); -} - -/** - * tpm2_seal_trusted() - seal the payload of a trusted key - * - * @chip: TPM chip to use - * @payload: the key data in clear and encrypted form - * @options: authentication values and other options - * - * Return: < 0 on error and 0 on success. - */ -int tpm2_seal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options) -{ - unsigned int blob_len; - struct tpm_buf buf; - u32 hash; - int i; - int rc; - - for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) { - if (options->hash == tpm2_hash_map[i].crypto_id) { - hash = tpm2_hash_map[i].tpm_id; - break; - } - } - - if (i == ARRAY_SIZE(tpm2_hash_map)) - return -EINVAL; - - rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE); - if (rc) - return rc; - - tpm_buf_append_u32(&buf, options->keyhandle); - tpm2_buf_append_auth(&buf, TPM2_RS_PW, - NULL /* nonce */, 0, - 0 /* session_attributes */, - options->keyauth /* hmac */, - TPM_DIGEST_SIZE); - - /* sensitive */ - tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1); - - tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE); - tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE); - tpm_buf_append_u16(&buf, payload->key_len + 1); - tpm_buf_append(&buf, payload->key, payload->key_len); - tpm_buf_append_u8(&buf, payload->migratable); - - /* public */ - tpm_buf_append_u16(&buf, 14 + options->policydigest_len); - tpm_buf_append_u16(&buf, TPM_ALG_KEYEDHASH); - tpm_buf_append_u16(&buf, hash); - - /* policy */ - if (options->policydigest_len) { - tpm_buf_append_u32(&buf, 0); - tpm_buf_append_u16(&buf, options->policydigest_len); - tpm_buf_append(&buf, options->policydigest, - options->policydigest_len); - } else { - tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH); - tpm_buf_append_u16(&buf, 0); - } - - /* public parameters */ - tpm_buf_append_u16(&buf, TPM_ALG_NULL); - tpm_buf_append_u16(&buf, 0); - - /* outside info */ - tpm_buf_append_u16(&buf, 0); - - /* creation PCR */ - tpm_buf_append_u32(&buf, 0); - - if (buf.flags & TPM_BUF_OVERFLOW) { - rc = -E2BIG; - goto out; - } - - rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data"); - if (rc) - goto out; - - blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]); - if (blob_len > MAX_BLOB_SIZE) { - rc = -E2BIG; - goto out; - } - if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 4 + blob_len) { - rc = -EFAULT; - goto out; - } - - memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len); - payload->blob_len = blob_len; - -out: - tpm_buf_destroy(&buf); - - if (rc > 0) { - if (tpm2_rc_value(rc) == TPM2_RC_HASH) - rc = -EINVAL; - else - rc = -EPERM; - } - - return rc; -} - -/** - * 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 - * - * Return: 0 on success. - * -E2BIG on wrong payload size. - * -EPERM on tpm error status. - * < 0 error from tpm_transmit_cmd. - */ -static int tpm2_load_cmd(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options, - u32 *blob_handle) -{ - struct tpm_buf buf; - unsigned int private_len; - unsigned int public_len; - unsigned int blob_len; - int rc; - - private_len = be16_to_cpup((__be16 *) &payload->blob[0]); - if (private_len > (payload->blob_len - 2)) - return -E2BIG; - - public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]); - blob_len = private_len + public_len + 4; - if (blob_len > payload->blob_len) - return -E2BIG; - - rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD); - if (rc) - return rc; - - tpm_buf_append_u32(&buf, options->keyhandle); - tpm2_buf_append_auth(&buf, TPM2_RS_PW, - NULL /* nonce */, 0, - 0 /* session_attributes */, - options->keyauth /* hmac */, - TPM_DIGEST_SIZE); - - tpm_buf_append(&buf, payload->blob, blob_len); - - if (buf.flags & TPM_BUF_OVERFLOW) { - rc = -E2BIG; - goto out; - } - - rc = tpm_transmit_cmd(chip, &buf, 4, "loading blob"); - if (!rc) - *blob_handle = be32_to_cpup( - (__be32 *) &buf.data[TPM_HEADER_SIZE]); - -out: - tpm_buf_destroy(&buf); - - if (rc > 0) - rc = -EPERM; - - return rc; -} - -/** - * tpm2_unseal_cmd() - execute a TPM2_Unload command - * - * @chip: TPM chip to use - * @payload: the key data in clear and encrypted form - * @options: authentication values and other options - * @blob_handle: blob handle - * - * Return: 0 on success - * -EPERM on tpm error status - * < 0 error from tpm_transmit_cmd - */ -static int tpm2_unseal_cmd(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options, - u32 blob_handle) -{ - struct tpm_buf buf; - u16 data_len; - u8 *data; - int rc; - - rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL); - if (rc) - return rc; - - tpm_buf_append_u32(&buf, blob_handle); - tpm2_buf_append_auth(&buf, - options->policyhandle ? - options->policyhandle : TPM2_RS_PW, - NULL /* nonce */, 0, - TPM2_SA_CONTINUE_SESSION, - options->blobauth /* hmac */, - TPM_DIGEST_SIZE); - - rc = tpm_transmit_cmd(chip, &buf, 6, "unsealing"); - if (rc > 0) - rc = -EPERM; - - if (!rc) { - data_len = be16_to_cpup( - (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]); - if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE + 1) { - rc = -EFAULT; - goto out; - } - - if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 6 + data_len) { - rc = -EFAULT; - goto out; - } - data = &buf.data[TPM_HEADER_SIZE + 6]; - - memcpy(payload->key, data, data_len - 1); - payload->key_len = data_len - 1; - payload->migratable = data[data_len - 1]; - } - -out: - tpm_buf_destroy(&buf); - return rc; -} - -/** - * tpm2_unseal_trusted() - unseal the payload of a trusted key - * - * @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_transmit_cmd. - */ -int tpm2_unseal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options) -{ - u32 blob_handle; - int rc; - - rc = tpm2_load_cmd(chip, payload, options, &blob_handle); - if (rc) - return rc; - - rc = tpm2_unseal_cmd(chip, payload, options, blob_handle); - tpm2_flush_context(chip, blob_handle); - return rc; -} - struct tpm2_get_cap_out { u8 more_data; __be32 subcap_id; diff --git a/include/keys/trusted_tpm.h b/include/keys/trusted_tpm.h index 7d7b108..77a2b5c 100644 --- a/include/keys/trusted_tpm.h +++ b/include/keys/trusted_tpm.h @@ -17,7 +17,7 @@ #define LOAD32N(buffer, offset) (*(uint32_t *)&buffer[offset]) #define LOAD16(buffer, offset) (ntohs(*(uint16_t *)&buffer[offset]))
-struct tpm_buf { +struct tpm1_buf { int len; unsigned char data[MAX_BUF_SIZE]; }; @@ -46,7 +46,14 @@ int TSS_checkhmac1(unsigned char *buffer, unsigned int keylen, ...);
int trusted_tpm_send(unsigned char *cmd, size_t buflen); -int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce); +int oiap(struct tpm1_buf *tb, uint32_t *handle, unsigned char *nonce); + +int tpm_seal_trusted(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options); +int tpm_unseal_trusted(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options);
#define TPM_DEBUG 0
@@ -84,7 +91,7 @@ static inline void dump_sess(struct osapsess *s) 16, 1, &s->enonce, SHA1_DIGEST_SIZE, 0); }
-static inline void dump_tpm_buf(unsigned char *buf) +static inline void dump_tpm1_buf(unsigned char *buf) { int len;
@@ -105,29 +112,29 @@ static inline void dump_sess(struct osapsess *s) { }
-static inline void dump_tpm_buf(unsigned char *buf) +static inline void dump_tpm1_buf(unsigned char *buf) { } #endif
-static inline void store8(struct tpm_buf *buf, const unsigned char value) +static inline void store8(struct tpm1_buf *buf, const unsigned char value) { buf->data[buf->len++] = value; }
-static inline void store16(struct tpm_buf *buf, const uint16_t value) +static inline void store16(struct tpm1_buf *buf, const uint16_t value) { *(uint16_t *) & buf->data[buf->len] = htons(value); buf->len += sizeof value; }
-static inline void store32(struct tpm_buf *buf, const uint32_t value) +static inline void store32(struct tpm1_buf *buf, const uint32_t value) { *(uint32_t *) & buf->data[buf->len] = htonl(value); buf->len += sizeof value; }
-static inline void storebytes(struct tpm_buf *buf, const unsigned char *in, +static inline void storebytes(struct tpm1_buf *buf, const unsigned char *in, const int len) { memcpy(buf->data + buf->len, in, len); diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 53c0ea9..5c43b41 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -21,6 +21,7 @@ #include <linux/acpi.h> #include <linux/cdev.h> #include <linux/fs.h> +#include <linux/highmem.h> #include <crypto/hash_info.h>
#define TPM_DIGEST_SIZE 20 /* Max TPM v1.2 PCR size */ @@ -161,6 +162,231 @@ struct tpm_chip { int locality; };
+#define TPM_HEADER_SIZE 10 + +struct tpm_header { + __be16 tag; + __be32 length; + union { + __be32 ordinal; + __be32 return_code; + }; +} __packed; + +enum tpm2_const { + TPM2_PLATFORM_PCR = 24, + TPM2_PCR_SELECT_MIN = ((TPM2_PLATFORM_PCR + 7) / 8), +}; + +enum tpm2_timeouts { + TPM2_TIMEOUT_A = 750, + TPM2_TIMEOUT_B = 2000, + TPM2_TIMEOUT_C = 200, + TPM2_TIMEOUT_D = 30, + TPM2_DURATION_SHORT = 20, + TPM2_DURATION_MEDIUM = 750, + TPM2_DURATION_LONG = 2000, + TPM2_DURATION_LONG_LONG = 300000, + TPM2_DURATION_DEFAULT = 120000, +}; + +enum tpm2_structures { + TPM2_ST_NO_SESSIONS = 0x8001, + TPM2_ST_SESSIONS = 0x8002, +}; + +/* 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) + +enum tpm2_return_codes { + TPM2_RC_SUCCESS = 0x0000, + TPM2_RC_HASH = 0x0083, /* RC_FMT1 */ + TPM2_RC_HANDLE = 0x008B, + TPM2_RC_INITIALIZE = 0x0100, /* RC_VER1 */ + TPM2_RC_FAILURE = 0x0101, + TPM2_RC_DISABLED = 0x0120, + TPM2_RC_COMMAND_CODE = 0x0143, + TPM2_RC_TESTING = 0x090A, /* RC_WARN */ + TPM2_RC_REFERENCE_H0 = 0x0910, + TPM2_RC_RETRY = 0x0922, +}; + +enum tpm2_command_codes { + TPM2_CC_FIRST = 0x011F, + TPM2_CC_HIERARCHY_CONTROL = 0x0121, + TPM2_CC_HIERARCHY_CHANGE_AUTH = 0x0129, + TPM2_CC_CREATE_PRIMARY = 0x0131, + TPM2_CC_SEQUENCE_COMPLETE = 0x013E, + TPM2_CC_SELF_TEST = 0x0143, + TPM2_CC_STARTUP = 0x0144, + TPM2_CC_SHUTDOWN = 0x0145, + TPM2_CC_NV_READ = 0x014E, + TPM2_CC_CREATE = 0x0153, + TPM2_CC_LOAD = 0x0157, + TPM2_CC_SEQUENCE_UPDATE = 0x015C, + TPM2_CC_UNSEAL = 0x015E, + TPM2_CC_CONTEXT_LOAD = 0x0161, + TPM2_CC_CONTEXT_SAVE = 0x0162, + TPM2_CC_FLUSH_CONTEXT = 0x0165, + TPM2_CC_VERIFY_SIGNATURE = 0x0177, + TPM2_CC_GET_CAPABILITY = 0x017A, + TPM2_CC_GET_RANDOM = 0x017B, + TPM2_CC_PCR_READ = 0x017E, + TPM2_CC_PCR_EXTEND = 0x0182, + TPM2_CC_EVENT_SEQUENCE_COMPLETE = 0x0185, + TPM2_CC_HASH_SEQUENCE_START = 0x0186, + TPM2_CC_CREATE_LOADED = 0x0191, + TPM2_CC_LAST = 0x0193, /* Spec 1.36 */ +}; + +enum tpm2_permanent_handles { + TPM2_RS_PW = 0x40000009, +}; + +enum tpm2_capabilities { + TPM2_CAP_HANDLES = 1, + TPM2_CAP_COMMANDS = 2, + TPM2_CAP_PCRS = 5, + TPM2_CAP_TPM_PROPERTIES = 6, +}; + +enum tpm2_properties { + TPM_PT_TOTAL_COMMANDS = 0x0129, +}; + +enum tpm2_startup_types { + TPM2_SU_CLEAR = 0x0000, + TPM2_SU_STATE = 0x0001, +}; + +enum tpm2_cc_attrs { + TPM2_CC_ATTR_CHANDLES = 25, + TPM2_CC_ATTR_RHANDLE = 28, +}; + +enum tpm_chip_flags { + TPM_CHIP_FLAG_TPM2 = BIT(1), + TPM_CHIP_FLAG_IRQ = BIT(2), + TPM_CHIP_FLAG_VIRTUAL = BIT(3), + TPM_CHIP_FLAG_HAVE_TIMEOUTS = BIT(4), + TPM_CHIP_FLAG_ALWAYS_POWERED = BIT(5), +}; + +enum tpm2_object_attributes { + TPM2_OA_USER_WITH_AUTH = BIT(6), +}; + +enum tpm2_session_attributes { + TPM2_SA_CONTINUE_SESSION = BIT(0), +}; + +struct tpm2_hash { + unsigned int crypto_id; + unsigned int tpm_id; +}; + +/* A string buffer type for constructing TPM commands. This is based on the + * ideas of string buffer code in security/keys/trusted_tpm.h but is heap based + * in order to keep the stack usage minimal. + */ + +enum tpm_buf_flags { + TPM_BUF_OVERFLOW = BIT(0), +}; + +struct tpm_buf { + struct page *data_page; + unsigned int flags; + u8 *data; +}; + +static inline void tpm_buf_reset(struct tpm_buf *buf, u16 tag, u32 ordinal) +{ + struct tpm_header *head = (struct tpm_header *)buf->data; + + head->tag = cpu_to_be16(tag); + head->length = cpu_to_be32(sizeof(*head)); + head->ordinal = cpu_to_be32(ordinal); +} + +static inline int tpm_buf_init(struct tpm_buf *buf, u16 tag, u32 ordinal) +{ + buf->data_page = alloc_page(GFP_HIGHUSER); + if (!buf->data_page) + return -ENOMEM; + + buf->flags = 0; + buf->data = kmap(buf->data_page); + tpm_buf_reset(buf, tag, ordinal); + return 0; +} + +static inline void tpm_buf_destroy(struct tpm_buf *buf) +{ + kunmap(buf->data_page); + __free_page(buf->data_page); +} + +static inline u32 tpm_buf_length(struct tpm_buf *buf) +{ + struct tpm_header *head = (struct tpm_header *)buf->data; + + return be32_to_cpu(head->length); +} + +static inline u16 tpm_buf_tag(struct tpm_buf *buf) +{ + struct tpm_header *head = (struct tpm_header *)buf->data; + + return be16_to_cpu(head->tag); +} + +static inline void tpm_buf_append(struct tpm_buf *buf, + const unsigned char *new_data, + unsigned int new_len) +{ + struct tpm_header *head = (struct tpm_header *)buf->data; + u32 len = tpm_buf_length(buf); + + /* Return silently if overflow has already happened. */ + if (buf->flags & TPM_BUF_OVERFLOW) + return; + + if ((len + new_len) > PAGE_SIZE) { + WARN(1, "tpm_buf: overflow\n"); + buf->flags |= TPM_BUF_OVERFLOW; + return; + } + + memcpy(&buf->data[len], new_data, new_len); + head->length = cpu_to_be32(len + new_len); +} + +static inline void tpm_buf_append_u8(struct tpm_buf *buf, const u8 value) +{ + tpm_buf_append(buf, &value, 1); +} + +static inline void tpm_buf_append_u16(struct tpm_buf *buf, const u16 value) +{ + __be16 value2 = cpu_to_be16(value); + + tpm_buf_append(buf, (u8 *) &value2, 2); +} + +static inline void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value) +{ + __be32 value2 = cpu_to_be32(value); + + tpm_buf_append(buf, (u8 *) &value2, 4); +} + +static inline u32 tpm2_rc_value(u32 rc) +{ + return (rc & BIT(7)) ? rc & 0xff : rc; +} + #if defined(CONFIG_TCG_TPM) || defined(CONFIG_TCG_TPM_MODULE)
extern int tpm_is_tpm2(struct tpm_chip *chip); @@ -170,13 +396,12 @@ extern int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, struct tpm_digest *digests); 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 int tpm_seal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options); -extern int tpm_unseal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options); extern struct tpm_chip *tpm_default_chip(void); +extern struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip); +extern void tpm_put_ops(struct tpm_chip *chip); +extern ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_buf *buf, + size_t min_rsp_body_length, const char *desc); +extern void tpm2_flush_context(struct tpm_chip *chip, u32 handle); #else static inline int tpm_is_tpm2(struct tpm_chip *chip) { @@ -204,21 +429,30 @@ static inline int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max) return -ENODEV; }
-static inline int tpm_seal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options) +static inline struct tpm_chip *tpm_default_chip(void) { - return -ENODEV; + return NULL; } -static inline int tpm_unseal_trusted(struct tpm_chip *chip, - struct trusted_key_payload *payload, - struct trusted_key_options *options) + +static inline struct tpm_chip *tpm_find_get_ops(struct tpm_chip *chip) +{ + return NULL; +} + +static inline void tpm_put_ops(struct tpm_chip *chip) +{ +} + +static inline ssize_t tpm_transmit_cmd(struct tpm_chip *chip, + struct tpm_buf *buf, + size_t min_rsp_body_length, + const char *desc) { return -ENODEV; } -static inline struct tpm_chip *tpm_default_chip(void) + +static inline void tpm2_flush_context(struct tpm_chip *chip, u32 handle) { - return NULL; } #endif #endif diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile index ad34d17..590a694 100644 --- a/security/keys/trusted-keys/Makefile +++ b/security/keys/trusted-keys/Makefile @@ -3,4 +3,5 @@ # Makefile for trusted keys #
-obj-$(CONFIG_TRUSTED_KEYS) += trusted-tpm.o +obj-$(CONFIG_TRUSTED_KEYS) += trusted-tpm.o \ + trusted-tpm2.o diff --git a/security/keys/trusted-keys/trusted-tpm.c b/security/keys/trusted-keys/trusted-tpm.c index b7e53a3..d09893b 100644 --- a/security/keys/trusted-keys/trusted-tpm.c +++ b/security/keys/trusted-keys/trusted-tpm.c @@ -368,9 +368,9 @@ int trusted_tpm_send(unsigned char *cmd, size_t buflen) if (!chip) return -ENODEV;
- dump_tpm_buf(cmd); + dump_tpm1_buf(cmd); rc = tpm_send(chip, cmd, buflen); - dump_tpm_buf(cmd); + dump_tpm1_buf(cmd); if (rc > 0) /* Can't return positive return codes values to keyctl */ rc = -EPERM; @@ -395,7 +395,7 @@ static int pcrlock(const int pcrnum) /* * Create an object specific authorisation protocol (OSAP) session */ -static int osap(struct tpm_buf *tb, struct osapsess *s, +static int osap(struct tpm1_buf *tb, struct osapsess *s, const unsigned char *key, uint16_t type, uint32_t handle) { unsigned char enonce[TPM_NONCE_SIZE]; @@ -430,7 +430,7 @@ static int osap(struct tpm_buf *tb, struct osapsess *s, /* * Create an object independent authorisation protocol (oiap) session */ -int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce) +int oiap(struct tpm1_buf *tb, uint32_t *handle, unsigned char *nonce) { int ret;
@@ -464,7 +464,7 @@ struct tpm_digests { * Have the TPM seal(encrypt) the trusted key, possibly based on * Platform Configuration Registers (PCRs). AUTH1 for sealing key. */ -static int tpm_seal(struct tpm_buf *tb, uint16_t keytype, +static int tpm_seal(struct tpm1_buf *tb, uint16_t keytype, uint32_t keyhandle, const unsigned char *keyauth, const unsigned char *data, uint32_t datalen, unsigned char *blob, uint32_t *bloblen, @@ -579,7 +579,7 @@ static int tpm_seal(struct tpm_buf *tb, uint16_t keytype, /* * use the AUTH2_COMMAND form of unseal, to authorize both key and blob */ -static int tpm_unseal(struct tpm_buf *tb, +static int tpm_unseal(struct tpm1_buf *tb, uint32_t keyhandle, const unsigned char *keyauth, const unsigned char *blob, int bloblen, const unsigned char *blobauth, @@ -670,7 +670,7 @@ static int tpm_unseal(struct tpm_buf *tb, static int key_seal(struct trusted_key_payload *p, struct trusted_key_options *o) { - struct tpm_buf *tb; + struct tpm1_buf *tb; int ret;
tb = kzalloc(sizeof *tb, GFP_KERNEL); @@ -696,7 +696,7 @@ static int key_seal(struct trusted_key_payload *p, static int key_unseal(struct trusted_key_payload *p, struct trusted_key_options *o) { - struct tpm_buf *tb; + struct tpm1_buf *tb; int ret;
tb = kzalloc(sizeof *tb, GFP_KERNEL); diff --git a/security/keys/trusted-keys/trusted-tpm2.c b/security/keys/trusted-keys/trusted-tpm2.c new file mode 100644 index 0000000..98892ed7 --- /dev/null +++ b/security/keys/trusted-keys/trusted-tpm2.c @@ -0,0 +1,378 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2004 IBM Corporation + * Copyright (C) 2014 Intel Corporation + * + * Authors: + * Leendert van Doorn leendert@watson.ibm.com + * Dave Safford safford@watson.ibm.com + * Reiner Sailer sailer@watson.ibm.com + * Kylene Hall kjhall@us.ibm.com + * + * Maintained by: tpmdd-devel@lists.sourceforge.net + * + * Trusted Keys code for TCG/TCPA TPM2 (trusted platform module). + */ + +#include <linux/string.h> +#include <linux/err.h> +#include <linux/tpm.h> +#include <linux/tpm_command.h> + +#include <keys/trusted-type.h> +#include <keys/trusted_tpm.h> + +static struct tpm2_hash tpm2_hash_map[] = { + {HASH_ALGO_SHA1, TPM_ALG_SHA1}, + {HASH_ALGO_SHA256, TPM_ALG_SHA256}, + {HASH_ALGO_SHA384, TPM_ALG_SHA384}, + {HASH_ALGO_SHA512, TPM_ALG_SHA512}, + {HASH_ALGO_SM3_256, TPM_ALG_SM3_256}, +}; + +/** + * tpm_buf_append_auth() - append TPMS_AUTH_COMMAND to the buffer. + * + * @buf: an allocated tpm_buf instance + * @session_handle: session handle + * @nonce: the session nonce, may be NULL if not used + * @nonce_len: the session nonce length, may be 0 if not used + * @attributes: the session attributes + * @hmac: the session HMAC or password, may be NULL if not used + * @hmac_len: the session HMAC or password length, maybe 0 if not used + */ +static void tpm2_buf_append_auth(struct tpm_buf *buf, u32 session_handle, + const u8 *nonce, u16 nonce_len, + u8 attributes, + const u8 *hmac, u16 hmac_len) +{ + tpm_buf_append_u32(buf, 9 + nonce_len + hmac_len); + tpm_buf_append_u32(buf, session_handle); + tpm_buf_append_u16(buf, nonce_len); + + if (nonce && nonce_len) + tpm_buf_append(buf, nonce, nonce_len); + + tpm_buf_append_u8(buf, attributes); + tpm_buf_append_u16(buf, hmac_len); + + if (hmac && hmac_len) + tpm_buf_append(buf, hmac, hmac_len); +} + +/** + * tpm2_seal_trusted() - seal the payload of a trusted key + * + * @chip: TPM chip to use + * @payload: the key data in clear and encrypted form + * @options: authentication values and other options + * + * Return: < 0 on error and 0 on success. + */ +int tpm2_seal_trusted(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options) +{ + unsigned int blob_len; + struct tpm_buf buf; + u32 hash; + int i; + int rc; + + for (i = 0; i < ARRAY_SIZE(tpm2_hash_map); i++) { + if (options->hash == tpm2_hash_map[i].crypto_id) { + hash = tpm2_hash_map[i].tpm_id; + break; + } + } + + if (i == ARRAY_SIZE(tpm2_hash_map)) + return -EINVAL; + + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_CREATE); + if (rc) + return rc; + + tpm_buf_append_u32(&buf, options->keyhandle); + tpm2_buf_append_auth(&buf, TPM2_RS_PW, + NULL /* nonce */, 0, + 0 /* session_attributes */, + options->keyauth /* hmac */, + TPM_DIGEST_SIZE); + + /* sensitive */ + tpm_buf_append_u16(&buf, 4 + TPM_DIGEST_SIZE + payload->key_len + 1); + + tpm_buf_append_u16(&buf, TPM_DIGEST_SIZE); + tpm_buf_append(&buf, options->blobauth, TPM_DIGEST_SIZE); + tpm_buf_append_u16(&buf, payload->key_len + 1); + tpm_buf_append(&buf, payload->key, payload->key_len); + tpm_buf_append_u8(&buf, payload->migratable); + + /* public */ + tpm_buf_append_u16(&buf, 14 + options->policydigest_len); + tpm_buf_append_u16(&buf, TPM_ALG_KEYEDHASH); + tpm_buf_append_u16(&buf, hash); + + /* policy */ + if (options->policydigest_len) { + tpm_buf_append_u32(&buf, 0); + tpm_buf_append_u16(&buf, options->policydigest_len); + tpm_buf_append(&buf, options->policydigest, + options->policydigest_len); + } else { + tpm_buf_append_u32(&buf, TPM2_OA_USER_WITH_AUTH); + tpm_buf_append_u16(&buf, 0); + } + + /* public parameters */ + tpm_buf_append_u16(&buf, TPM_ALG_NULL); + tpm_buf_append_u16(&buf, 0); + + /* outside info */ + tpm_buf_append_u16(&buf, 0); + + /* creation PCR */ + tpm_buf_append_u32(&buf, 0); + + if (buf.flags & TPM_BUF_OVERFLOW) { + rc = -E2BIG; + goto out; + } + + rc = tpm_transmit_cmd(chip, &buf, 4, "sealing data"); + if (rc) + goto out; + + blob_len = be32_to_cpup((__be32 *) &buf.data[TPM_HEADER_SIZE]); + if (blob_len > MAX_BLOB_SIZE) { + rc = -E2BIG; + goto out; + } + if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 4 + blob_len) { + rc = -EFAULT; + goto out; + } + + memcpy(payload->blob, &buf.data[TPM_HEADER_SIZE + 4], blob_len); + payload->blob_len = blob_len; + +out: + tpm_buf_destroy(&buf); + + if (rc > 0) { + if (tpm2_rc_value(rc) == TPM2_RC_HASH) + rc = -EINVAL; + else + rc = -EPERM; + } + + return rc; +} + +/** + * tpm_seal_trusted() - seal a trusted key payload + * @chip: a &struct tpm_chip instance, %NULL for the default chip + * @options: authentication values and other options + * @payload: the key data in clear and encrypted form + * + * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in + * the keyring subsystem. + * + * Return: same as with tpm_transmit_cmd() + */ +int tpm_seal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, + struct trusted_key_options *options) +{ + int rc; + + chip = tpm_find_get_ops(chip); + if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2)) + return -ENODEV; + + rc = tpm2_seal_trusted(chip, payload, options); + + tpm_put_ops(chip); + return rc; +} + +/** + * 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 + * + * Return: 0 on success. + * -E2BIG on wrong payload size. + * -EPERM on tpm error status. + * < 0 error from tpm_transmit_cmd. + */ +static int tpm2_load_cmd(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options, + u32 *blob_handle) +{ + struct tpm_buf buf; + unsigned int private_len; + unsigned int public_len; + unsigned int blob_len; + int rc; + + private_len = be16_to_cpup((__be16 *) &payload->blob[0]); + if (private_len > (payload->blob_len - 2)) + return -E2BIG; + + public_len = be16_to_cpup((__be16 *) &payload->blob[2 + private_len]); + blob_len = private_len + public_len + 4; + if (blob_len > payload->blob_len) + return -E2BIG; + + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_LOAD); + if (rc) + return rc; + + tpm_buf_append_u32(&buf, options->keyhandle); + tpm2_buf_append_auth(&buf, TPM2_RS_PW, + NULL /* nonce */, 0, + 0 /* session_attributes */, + options->keyauth /* hmac */, + TPM_DIGEST_SIZE); + + tpm_buf_append(&buf, payload->blob, blob_len); + + if (buf.flags & TPM_BUF_OVERFLOW) { + rc = -E2BIG; + goto out; + } + + rc = tpm_transmit_cmd(chip, &buf, 4, "loading blob"); + if (!rc) + *blob_handle = be32_to_cpup( + (__be32 *) &buf.data[TPM_HEADER_SIZE]); + +out: + tpm_buf_destroy(&buf); + + if (rc > 0) + rc = -EPERM; + + return rc; +} + +/** + * tpm2_unseal_cmd() - execute a TPM2_Unload command + * + * @chip: TPM chip to use + * @payload: the key data in clear and encrypted form + * @options: authentication values and other options + * @blob_handle: blob handle + * + * Return: 0 on success + * -EPERM on tpm error status + * < 0 error from tpm_transmit_cmd + */ +static int tpm2_unseal_cmd(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options, + u32 blob_handle) +{ + struct tpm_buf buf; + u16 data_len; + u8 *data; + int rc; + + rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_UNSEAL); + if (rc) + return rc; + + tpm_buf_append_u32(&buf, blob_handle); + tpm2_buf_append_auth(&buf, + options->policyhandle ? + options->policyhandle : TPM2_RS_PW, + NULL /* nonce */, 0, + TPM2_SA_CONTINUE_SESSION, + options->blobauth /* hmac */, + TPM_DIGEST_SIZE); + + rc = tpm_transmit_cmd(chip, &buf, 6, "unsealing"); + if (rc > 0) + rc = -EPERM; + + if (!rc) { + data_len = be16_to_cpup( + (__be16 *) &buf.data[TPM_HEADER_SIZE + 4]); + if (data_len < MIN_KEY_SIZE || data_len > MAX_KEY_SIZE + 1) { + rc = -EFAULT; + goto out; + } + + if (tpm_buf_length(&buf) < TPM_HEADER_SIZE + 6 + data_len) { + rc = -EFAULT; + goto out; + } + data = &buf.data[TPM_HEADER_SIZE + 6]; + + memcpy(payload->key, data, data_len - 1); + payload->key_len = data_len - 1; + payload->migratable = data[data_len - 1]; + } + +out: + tpm_buf_destroy(&buf); + return rc; +} + +/** + * tpm2_unseal_trusted() - unseal the payload of a trusted key + * + * @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_transmit_cmd. + */ +int tpm2_unseal_trusted(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options) +{ + u32 blob_handle; + int rc; + + rc = tpm2_load_cmd(chip, payload, options, &blob_handle); + if (rc) + return rc; + + rc = tpm2_unseal_cmd(chip, payload, options, blob_handle); + tpm2_flush_context(chip, blob_handle); + return rc; +} + +/** + * tpm_unseal_trusted() - unseal a trusted key + * @chip: a &struct tpm_chip instance, %NULL for the default chip + * @options: authentication values and other options + * @payload: the key data in clear and encrypted form + * + * Note: only TPM 2.0 chip are supported. TPM 1.x implementation is located in + * the keyring subsystem. + * + * Return: same as with tpm_transmit_cmd() + */ +int tpm_unseal_trusted(struct tpm_chip *chip, + struct trusted_key_payload *payload, + struct trusted_key_options *options) +{ + int rc; + + chip = tpm_find_get_ops(chip); + if (!chip || !(chip->flags & TPM_CHIP_FLAG_TPM2)) + return -ENODEV; + + rc = tpm2_unseal_trusted(chip, payload, options); + + tpm_put_ops(chip); + + return rc; +}