diff options
Diffstat (limited to 'ks.h')
| -rw-r--r-- | ks.h | 113 |
1 files changed, 105 insertions, 8 deletions
@@ -147,20 +147,45 @@ typedef struct { } hal_ks_cache_block_t; /* - * Medium-specific driver and in-memory database. + * Keystore object. hal_internal.h typedefs this to hal_ks_t. * - * The top-level structure is a static variable; the arrays are - * allocated at runtime using hal_allocate_static_memory() because - * they can get kind of large. + * We expect this to be a static variable, but we expect the arrays in + * it to be allocated at runtime using hal_allocate_static_memory() + * because they can get kind of large. * * Driver-specific stuff is handled by a form of subclassing: the * driver embeds the hal_ks_t structure at the head of whatever else * it needs, and performs (controlled, type-safe) casts as needed. + * + * Core of this is the keystore index. This is intended to be usable + * by both memory-based and flash-based keystores. Some of the + * features aren't necessary for memory-based keystores, but should be + * harmless, and let us keep the drivers simple. + * + * General approach is multiple arrays, all but one of which are + * indexed by "block" numbers, where a block number might be a slot in + * yet another static array, the number of a flash sub-sector, or + * whatever is the appropriate unit for holding one keystore record. + * + * The index array only contains block numbers. This is a small data + * structure so that moving data within it is relatively cheap. + * + * The index array is divided into two portions: the index proper, and + * the free queue. The index proper is ordered according to the names + * (UUIDs) of the corresponding blocks; the free queue is a FIFO, to + * support a simplistic form of wear leveling in flash-based keystores. + * + * Key names are kept in a separate array, indexed by block number. + * + * The all-zeros UUID, which (by definition) cannot be a valid key + * UUID, is reserved for the (non-key) block used to stash PINs and + * other small data which aren't really part of the keystore proper + * but are kept with it because the keystore is the flash we have. + * + * Note that this API deliberately says nothing about how the keys + * themselves are stored, that's up to the keystore driver. */ -typedef struct hal_ks_driver hal_ks_driver_t; -typedef struct hal_ks hal_ks_t; - struct hal_ks { const hal_ks_driver_t *driver; unsigned size; /* Blocks in keystore */ @@ -173,6 +198,19 @@ struct hal_ks { int per_session; /* Whether objects have per-session semantics (PKCS #11, sigh) */ }; +/* + * Keystore driver. This is just a dispatch vector for low-level + * keystore operations, and the code is very repetitive. We opt for + * expressing this in a terse form via C macros over expressing it + * as huge chunks of repetitive code: both are difficult to read, but + * the terse form has the advantage of fitting in a single screen. + * The KS_DRIVER_METHODS macro is the protein, the rest is just the + * machinery to expand the method definitions into a struct of typed + * function pointers and a set of static inline wrapper functions. + */ + +typedef struct hal_ks_driver hal_ks_driver_t; + #define KS_DRIVER_END_LIST #define KS_DRIVER_METHODS \ KS_DRIVER_METHOD(read, hal_ks_t *ks, const unsigned blockno, hal_ks_block_t *block) \ @@ -187,7 +225,7 @@ struct hal_ks { const hal_client_handle_t client, const hal_session_handle_t session) \ KS_DRIVER_END_LIST -#define KS_DRIVER_METHOD(_name_, ...) hal_error_t (*_name_)(__VA_ARGS__) +#define KS_DRIVER_METHOD(_name_, ...) hal_error_t (*_name_)(__VA_ARGS__); struct hal_ks_driver { KS_DRIVER_METHODS }; #undef KS_DRIVER_METHOD @@ -208,6 +246,65 @@ KS_DRIVER_METHODS #endif /* _KS_H_ */ /* + * Keystore utilities. Some or all of these may end up static within ks.c. + */ + +extern hal_error_t hal_ks_alloc_common(hal_ks_t *ks, + const unsigned ks_blocks, + const unsigned cache_blocks); + +extern hal_error_t hal_ks_init_common(hal_ks_t *ks, + const hal_ks_driver_t * const driver); + +extern hal_error_t hal_ks_index_heapsort(hal_ks_t *ks); + +extern hal_error_t hal_ks_index_find(hal_ks_t *ks, + const hal_uuid_t * const name, + unsigned *blockno, + int *hint); + +extern hal_error_t hal_ks_index_add(hal_ks_t *ks, + const hal_uuid_t * const name, + unsigned *blockno, + int *hint); + +extern hal_error_t hal_ks_index_delete(hal_ks_t *ks, + const hal_uuid_t * const name, + unsigned *blockno, + int *hint); + +extern hal_error_t hal_ks_index_replace(hal_ks_t *ks, + const hal_uuid_t * const name, + unsigned *blockno, + int *hint); + +extern hal_error_t hal_ks_index_fsck(hal_ks_t *ks); + +extern const size_t hal_ks_attribute_header_size; + +extern hal_error_t hal_ks_attribute_scan(const uint8_t * const bytes, + const size_t bytes_len, + hal_pkey_attribute_t *attributes, + const unsigned attributes_len, + size_t *total_len); + +extern hal_error_t hal_ks_attribute_delete(uint8_t *bytes, + const size_t bytes_len, + hal_pkey_attribute_t *attributes, + unsigned *attributes_len, + size_t *total_len, + const uint32_t type); + +extern hal_error_t hal_ks_attribute_insert(uint8_t *bytes, const size_t bytes_len, + hal_pkey_attribute_t *attributes, + unsigned *attributes_len, + size_t *total_len, + const uint32_t type, + const uint8_t * const value, + const size_t value_len); + + +/* * Local variables: * indent-tabs-mode: nil * End: |