/*!
* @header
* Provides an interface for managing nonces to govern the lifetime of a
* personalization performed with TSS. A nonce managed by this interface may
* be used in a TSS signing request as the value for the BNCH tag.
*
* These interfaces require the caller to possess the
*
* com.apple.private.security.AppleImage4.user-client
*
* entitlement.
*
* @section Threat Model
* The adversary possesses the following:
*
* 1. a manifest which was previously valid but has since been invalidated
* by rolling the nonce associated with it
* 2. user-level code execution
* 3. knowledge of the raw nonce value for the previously-valid manifest
*
* The defense against this adversary is a system in which knowledge of the raw
* nonce is insufficient to impact the evaluation of a personalization. This
* system has the following characteristics:
*
* 1. A nonce seed is stored in an nvram variable which is only writable by
* the kernel
* 2. When making a new signing request, the nonce seed is encrypted by a
* UID1-derived key in-kernel and then hashed -- the output of this
* operation the nonce to be used in the signing request
* 3. On boot, AppleImage4 obtains the nonce seed from nvram and stores it
* in a data structure which will be covered by KTRR
* 4. When evaluating a manifest, AppleImage4 reads the raw nonce from the
* KTRR-covered data structure and validates it with the same
* transformation as was done in (2)
* 5. When the nonce is to be invalidated, AppleImage4 sets a flag in an
* nvram variable which is only writable by the kernel
* 6. On the subsequent boot, AppleImage4 notices the flag, generates a new
* nonce and repeats the procedure in (3)
*
* In this system, the raw nonce seed never leaves the kernel, and the nonce
* itself is a non-reversible representation of the seed.
*/
#ifndef __IMG4_NONCE_H
#define __IMG4_NONCE_H
#ifndef __IMG4_INDIRECT
#error "Please #include <img4/firmware.h> instead of this file directly"
#endif // __IMG4_INDIRECT
__BEGIN_DECLS
OS_ASSUME_NONNULL_BEGIN
OS_ASSUME_PTR_ABI_SINGLE_BEGIN
/*!
* @typedef img4_nonce_domain_t
* An opaque type describing a nonce domain.
*/
IMG4_API_AVAILABLE_20181106
typedef struct _img4_nonce_domain img4_nonce_domain_t;
/*!
* @const IMG4_NONCE_STRUCT_VERSION
* The version of the {@link img4_nonce_t} structure supported by the
* implementation.
*/
#define IMG4_NONCE_STRUCT_VERSION ((img4_struct_version_t)0)
#define IMG4_NONCE_VERSION IMG4_NONCE_STRUCT_VERSION
/*!
* @const IMG4_NONCE_MAX_LENGTH
* The maximum length of a nonce. Currently, this is the length of a SHA2-384
* hash.
*/
#define IMG4_NONCE_MAX_LENGTH (48u)
/*!
* @typedef img4_nonce_domain_index_t
* An enumeration describing nonce domains.
*
* @const IMG4_NONCE_DOMAIN_INDEX_TEST
* The enumerated constant corresponding to the internal test nonce domain.
*
* @const IMG4_NONCE_DOMAIN_INDEX_TRUST_CACHE
* The enumerated constant corresponding to
* {@link IMG4_NONCE_DOMAIN_TRUST_CACHE}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_PDI
* The enumerated constant corresponding to {@link IMG4_NONCE_DOMAIN_TRUST_PDI}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_CRYPTEX
* The enumerated constant corresponding to {@link IMG4_NONCE_DOMAIN_CRYPTEX}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_DDI
* The enumerated constant corresponding to {@link IMG4_NONCE_DOMAIN_DDI}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_EPHEMERAL_CRYPTEX
* The enumerated constant corresponding to
* {@link IMG4_NONCE_DOMAIN_EPHEMERAL_CRYPTEX}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_SNUF_STUB
* The enumerated constant corresponding to
* {@link IMG4_NONCE_DOMAIN_CRYPTEX1_SNUF_STUB}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_BOOT
* The enumerated constant corresponding to
* {@link IMG4_NONCE_DOMAIN_CRYPTEX1_BOOT}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_ASSET
* The enumerated constant corresponding to
* {@link IMG4_NONCE_DOMAIN_CRYPTEX1_ASSET}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_GENERIC
* The enumerated constant corresponding to
* {@link IMG4_NONCE_DOMAIN_CRYPTEX1_GENERIC}.
*
* @const IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_SIMULATOR
* The enumerated constant corresponding to
* {@link IMG4_NONCE_DOMAIN_CRYPTEX1_SIMULATOR}.
*
* @const _IMG4_NONCE_DOMAIN_INDEX_CNT
* A sentinel value indicating the number of nonce domains.
*/
IMG4_API_AVAILABLE_20210521
OS_CLOSED_ENUM(img4_nonce_domain_index, uint64_t,
IMG4_NONCE_DOMAIN_INDEX_TEST = 0,
IMG4_NONCE_DOMAIN_INDEX_TRUST_CACHE,
IMG4_NONCE_DOMAIN_INDEX_PDI,
IMG4_NONCE_DOMAIN_INDEX_CRYPTEX,
IMG4_NONCE_DOMAIN_INDEX_DDI,
IMG4_NONCE_DOMAIN_INDEX_EPHEMERAL_CRYPTEX,
IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_SNUF_STUB,
IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_BOOT,
IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_ASSET,
IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_GENERIC,
IMG4_NONCE_DOMAIN_INDEX_CRYPTEX1_SIMULATOR,
_IMG4_NONCE_DOMAIN_INDEX_CNT,
);
/*!
* @typedef img4_nonce_t
* A structure describing a nonce.
*
* @field i4n_version
* The version of the structure. When declaring this structure, you must
* initialize this field to {@link IMG4_NONCE_VERSION}.
*
* @field i4n_nonce
* The bytes comprising the nonce.
*
* @field i4n_length
* The length of the nonce. Will be at most {@link IMG4_NONCE_MAX_LENGTH}.
*
* @discussion
* The {@link i4n_nonce} field was previously const. This was a terrible idea,
* and the const storage qualifier was removed without adjusting the structure
* version.
*/
IMG4_API_AVAILABLE_20181106
typedef struct _img4_nonce {
img4_struct_version_t i4n_version;
uint8_t i4n_nonce[IMG4_NONCE_MAX_LENGTH];
uint32_t i4n_length;
} img4_nonce_t;
/*!
* @const IMG4_NONCE_INIT
* A convenience initializer for {@link img4_nonce_t} which ensures that the
* {@link i4n_version} field is properly initialized.
*/
#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
#define IMG4_NONCE_INIT (img4_nonce_t){.i4n_version = IMG4_NONCE_STRUCT_VERSION}
#elif defined(__cplusplus) && __cplusplus >= 201103L
#define IMG4_NONCE_INIT (img4_nonce_t{IMG4_NONCE_STRUCT_VERSION})
#elif defined(__cplusplus)
#define IMG4_NONCE_INIT \
(img4_nonce_t((img4_nonce_t){IMG4_NONCE_STRUCT_VERSION}))
#else
#define IMG4_NONCE_INIT {IMG4_NONCE_STRUCT_VERSION}
#endif
/*!
* @const IMG4_NONCE_ZERO
* A convenience initializer for {@link img4_nonce_t} which initializes a 48-
* byte nonce of all zeroes.
*/
#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
#define IMG4_NONCE_ZERO (img4_nonce_t){ \
.i4n_version = IMG4_NONCE_STRUCT_VERSION, \
.i4n_nonce = {0}, \
.i4n_length = IMG4_NONCE_MAX_LENGTH, \
}
#endif
/*!
* @const IMG4_NONCE_DOMAIN_TRUST_CACHE
* The nonce domain governing trust cache personalizations. Use of this domain
* requires the
*
* com.apple.private.img4.nonce.trust-cache
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20181106
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_trust_cache;
#define IMG4_NONCE_DOMAIN_TRUST_CACHE (&_img4_nonce_domain_trust_cache)
#else
#define IMG4_NONCE_DOMAIN_TRUST_CACHE (img4if->i4if_v1.nonce_domain_trust_cache)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_PDI
* The nonce domain governing disk image personalizations. Use of this domain
* requires the
*
* com.apple.private.img4.nonce.pdi
*
* entitlement. The nonce for this domain is regenerated once every boot.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20181106
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_pdi;
#define IMG4_NONCE_DOMAIN_PDI (&_img4_nonce_domain_pdi)
#else
#define IMG4_NONCE_DOMAIN_PDI (img4if->i4if_v3.nonce_domain_pdi)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_CRYPTEX
* The nonce domain governing cryptex personalizations. Use of this domain
* requires the
*
* com.apple.private.img4.nonce.cryptex
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20181106
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_cryptex;
#define IMG4_NONCE_DOMAIN_CRYPTEX (&_img4_nonce_domain_cryptex)
#else
#define IMG4_NONCE_DOMAIN_CRYPTEX (img4if->i4if_v3.nonce_domain_cryptex)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_DDI
* The nonce domain governing developer disk image personalizations. Use of this
* domain requires the
*
* com.apple.private.img4.nonce.ddi
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20181106
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_ddi;
#define IMG4_NONCE_DOMAIN_DDI (&_img4_nonce_domain_ddi)
#else
#define IMG4_NONCE_DOMAIN_DDI (img4if->i4if_v12.nonce_domain_ddi)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_EPHEMERAL_CRYPTEX
* The nonce domain governing ephemeral cryptex personalizations. Use of this
* domain requires the
*
* com.apple.private.img4.nonce.ephemeral-cryptex
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20210305
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_ephemeral_cryptex;
#define IMG4_NONCE_DOMAIN_EPHEMERAL_CRYPTEX \
(&_img4_nonce_domain_ephemeral_cryptex)
#else
#define IMG4_NONCE_DOMAIN_EPHEMERAL_CRYPTEX \
(img4if->i4if_v12.nonce_domain_ephemeral_cryptex)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_CRYPTEX1_SNUF_STUB
* The nonce domain which acts as a null stub for the snuf value for Cryptex1
* processors. This domain corresponds to a value of 0 for the
* Cryptex1,NonceDomain tag. Use of this domain requires the
*
* com.apple.private.img4.nonce.cryptex1.snuf-stub
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20220322
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_cryptex1_snuf_stub;
#define IMG4_NONCE_DOMAIN_CRYPTEX1_SNUF_STUB \
(&_img4_nonce_domain_cryptex1_snuf_stub)
#else
#define IMG4_NONCE_DOMAIN_CRYPTEX1_SNUF_STUB \
(img4if->i4if_v18.nonce_domain_cryptex1_snuf_stub)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_CRYPTEX1_BOOT
* The nonce domain governing personalizations for the virtual Cryptex1
* coprocessor's boot objects. This domain corresponds to a value of 1 for the
* Cryptex1,NonceDomain tag. Use of this domain requires the
*
* com.apple.private.img4.nonce.cryptex1.boot
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20211112
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_cryptex1_boot;
#define IMG4_NONCE_DOMAIN_CRYPTEX1_BOOT \
(&_img4_nonce_domain_cryptex1_boot)
#else
#define IMG4_NONCE_DOMAIN_CRYPTEX1_BOOT \
(img4if->i4if_v16.nonce_domain_cryptex1_boot)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_CRYPTEX1_ASSET
* The nonce domain governing personalizations for the virtual Cryptex1
* coprocessor's asset brain objects. This domain corresponds to a value of 2
* for the Cryptex1,NonceDomain tag. Use of this domain requires the
*
* com.apple.private.img4.nonce.cryptex1.asset
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20211112
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_cryptex1_asset;
#define IMG4_NONCE_DOMAIN_CRYPTEX1_ASSET \
(&_img4_nonce_domain_cryptex1_asset)
#else
#define IMG4_NONCE_DOMAIN_CRYPTEX1_ASSET \
(img4if->i4if_v16.nonce_domain_cryptex1_asset)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_CRYPTEX1_GENERIC
* The nonce domain governing personalizations for the virtual Cryptex1
* coprocessor's generic supplemental objects. This domain corresponds to a
* value of 3 for the Cryptex1,NonceDomain tag. Use of this domain requires the
*
* com.apple.private.img4.nonce.cryptex1.supplemental
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20221202
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_cryptex1_generic;
#define IMG4_NONCE_DOMAIN_CRYPTEX1_GENERIC \
(&_img4_nonce_domain_cryptex1_generic)
#else
#define IMG4_NONCE_DOMAIN_CRYPTEX1_GENERIC \
(img4if->i4if_v20.nonce_domain_cryptex1_generic)
#endif
/*!
* @const IMG4_NONCE_DOMAIN_CRYPTEX1_SIMULATOR
* The nonce domain governing personalizations for the virtual Cryptex1
* coprocessor's Simulator runtime objects. This domain corresponds to a value
* of 4 for the Cryptex1,NonceDomain tag. Use of this domain requires the
*
* com.apple.private.img4.nonce.cryptex1.simulator
*
* entitlement.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20221202
OS_EXPORT
const struct _img4_nonce_domain _img4_nonce_domain_cryptex1_simulator;
#define IMG4_NONCE_DOMAIN_CRYPTEX1_SIMULATOR \
(&_img4_nonce_domain_cryptex1_simulator)
#else
#define IMG4_NONCE_DOMAIN_CRYPTEX1_SIMULATOR \
(img4if->i4if_v20.nonce_domain_cryptex1_simulator)
#endif
/*!
* @function img4_nonce_domain_copy_nonce
* Copies the current value of the nonce in the given domain.
*
* @param nd
* The nonce domain.
*
* @param n
* Upon successful return, storage that will contain the current nonce. The
* provided structure's {@link i4n_version} must be initialized to
* {@link IMG4_NONCE_VERSION}.
*
* @result
* Upon success, zero is returned. The implementation may also return one of the
* following error codes directly:
*
* [ESTALE] The nonce for the given domain has been invalidated, and the
* host must reboot in order to generate a new one
* [EPERM] The caller lacked the entitlement necessary to read the
* given nonce
* [ENOTSUP] Nonce management is not available on the host
* [EACCES] The nonce requested is not accessible in this environment
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20210305
OS_EXPORT OS_WARN_RESULT OS_NONNULL1 OS_NONNULL2
errno_t
img4_nonce_domain_copy_nonce(const img4_nonce_domain_t *nd, img4_nonce_t *n);
#else
#define img4_nonce_domain_copy_nonce(...) \
(img4if->i4if_v1.nonce_domain_copy_nonce(__VA_ARGS__))
#endif
/*!
* @function img4_nonce_domain_roll_nonce
* Invalidates the current nonce for the given domain and forces a re-generation
* of the domain's nonce seed at the next boot.
*
* @param nd
* The nonce domain.
*
* @result
* Upon success, zero is returned. The kernel implementation will never return
* a non-zero code. The userspace implementation may return one of the following
* error codes directly:
*
* [EPERM] The caller lacked the entitlement necessary to roll the
* given nonce
* [EROFS] The boot mode didn't allow committing to non-volatile storage
* [ENOTSUP] Nonce management is not available on the host
* [EACCES] The nonce requested is not accessible in this environment
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20181106
OS_EXPORT OS_WARN_RESULT OS_NONNULL1
errno_t
img4_nonce_domain_roll_nonce(const img4_nonce_domain_t *nd);
#else
#define img4_nonce_domain_roll_nonce(...) \
(img4if->i4if_v1.nonce_domain_roll_nonce(__VA_ARGS__))
#endif
/*!
* @function img4_nonce_domain_preroll_nonce
* Generates a new nonce seed and returns the resulting hash. The new nonce seed
* will be in force at the next reboot if and only if the boot manifest hash
* changes. Otherwise, the current nonce seed value will remain stable (modulo
* the regeneration policy associated with its domain).
*
* @param nd
* The nonce domain.
*
* @param n
* Upon successful return, storage that will contain the current nonce. The
* provided structure's {@link i4n_version} must be initialized to
* {@link IMG4_NONCE_VERSION}.
*
* @result
* Upon success, zero is returned. The kernel implementation will never return
* a non-zero code. The userspace implementation may return one of the following
* error codes directly:
*
* [EPERM] The caller lacked the entitlement necessary to roll the
* given nonce
* [EROFS] The boot mode didn't allow committing to non-volatile storage
* [ENOTSUP] Nonce management is not available on the host
* [EACCES] The nonce requested is not accessible in this environment
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_FALL_2021_B
OS_EXPORT OS_WARN_RESULT OS_NONNULL1 OS_NONNULL2
errno_t
img4_nonce_domain_preroll_nonce(const img4_nonce_domain_t *nd, img4_nonce_t *n);
#else
#define img4_nonce_domain_preroll_nonce(...) \
(img4if->i4if_v14.nonce_domain_preroll_nonce(__VA_ARGS__))
#endif
/*!
* @function img4_nonce_domain_peek_nonce
* Copies the current proposed value of a nonce domain.
*
* @param nd
* The nonce domain.
*
* @param n
* Upon successful return, storage that will contain the current proposed
* nonce. The provided structure's {@link i4n_version} must be initialized to
* {@link IMG4_NONCE_VERSION}.
*
* @result
* Upon success, zero is returned. The implementation may also return one of the
* following error codes directly:
*
* [EPERM] The caller lacked the entitlement necessary to roll the
* given nonce
* [ENOENT] The nonce doesn't have a proposed value
* [ENOTSUP] Nonce management is not available on the host
* [EACCES] The nonce requested is not accessible in this environment
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20220714
OS_EXPORT OS_WARN_RESULT OS_NONNULL1 OS_NONNULL2
errno_t
img4_nonce_domain_peek_nonce(const img4_nonce_domain_t *nd, img4_nonce_t *n);
#else
#define img4_nonce_domain_peek_nonce(...) \
(img4if->i4if_v19.nonce_domain_peek_nonce(__VA_ARGS__))
#endif
/*!
* @function img4_nonce_domain_get_from_handle
* Obtains the nonce domain for the given integer handle.
*
* @param handle
* The nonce domain handle.
*
* @result
* The nonce domain associated with the provided handle. If no domain is
* associated with the handle, NULL is returned.
*/
#if !XNU_KERNEL_PRIVATE
IMG4_API_AVAILABLE_20221202
OS_EXPORT OS_WARN_RESULT
const img4_nonce_domain_t *_Nullable
img4_nonce_domain_get_from_handle(uint32_t handle);
#else
#define img4_nonce_domain_get_from_handle(...) \
(img4if->i4if_v20.nonce_domain_get_from_handle(__VA_ARGS__))
#endif
OS_ASSUME_PTR_ABI_SINGLE_END
OS_ASSUME_NONNULL_END
__END_DECLS
#endif // __IMG4_NONCE_H