diff options
Diffstat (limited to 'common/vboot_hash.c')
| -rw-r--r-- | common/vboot_hash.c | 165 |
1 files changed, 83 insertions, 82 deletions
diff --git a/common/vboot_hash.c b/common/vboot_hash.c index abc67ebe00..bd80fbde2d 100644 --- a/common/vboot_hash.c +++ b/common/vboot_hash.c @@ -28,7 +28,9 @@ struct vboot_hash_tag { #define VBOOT_HASH_SYSJUMP_TAG 0x5648 /* "VH" */ #define VBOOT_HASH_SYSJUMP_VERSION 1 -#define CHUNK_SIZE 1024 + +#define CHUNK_SIZE 1024 /* Bytes to hash per deferred call */ +#define WORK_INTERVAL_US 100 /* Delay between deferred calls */ static uint32_t data_offset; static uint32_t data_size; @@ -39,10 +41,65 @@ static int in_progress; static struct sha256_ctx ctx; -/* +/** + * Abort hash currently in progress, and invalidate any completed hash. + */ +static void vboot_hash_abort(void) +{ + if (in_progress) { + want_abort = 1; + } else { + CPRINTF("[%T hash abort]\n"); + want_abort = 0; + data_size = 0; + hash = NULL; + } +} + +/** + * Do next chunk of hashing work, if any. + */ +static void vboot_hash_next_chunk(void) +{ + int size; + + /* Handle abort */ + if (want_abort) { + in_progress = 0; + vboot_hash_abort(); + return; + } + + /* Compute the next chunk of hash */ + size = MIN(CHUNK_SIZE, data_size - curr_pos); + SHA256_update(&ctx, (const uint8_t *)(CONFIG_FLASH_BASE + + data_offset + curr_pos), size); + + curr_pos += size; + if (curr_pos >= data_size) { + /* Store the final hash */ + hash = SHA256_final(&ctx); + CPRINTF("[%T hash done %.*h]\n", SHA256_DIGEST_SIZE, hash); + + in_progress = 0; + + /* Handle receiving abort during finalize */ + if (want_abort) + vboot_hash_abort(); + + return; + } + + /* If we're still here, more work to do; come back later */ + hook_call_deferred(vboot_hash_next_chunk, WORK_INTERVAL_US); +} +DECLARE_DEFERRED(vboot_hash_next_chunk); + +/** * Start computing a hash of <size> bytes of data at flash offset <offset>. - * If nonce_size is non-zero, prefixes the <nonce> onto the data to be - * hashed. Returns non-zero if error. + * + * If nonce_size is non-zero, prefixes the <nonce> onto the data to be hashed. + * Returns non-zero if error. */ static int vboot_hash_start(uint32_t offset, uint32_t size, const uint8_t *nonce, int nonce_size) @@ -74,25 +131,34 @@ static int vboot_hash_start(uint32_t offset, uint32_t size, if (nonce_size) SHA256_update(&ctx, nonce, nonce_size); - /* Wake the hash task */ - task_wake(TASK_ID_VBOOTHASH); + hook_call_deferred(vboot_hash_next_chunk, 0); return EC_SUCCESS; } -/* Abort hash currently in progress, and invalidate any completed hash. */ -static void vboot_hash_abort(void) +int vboot_hash_invalidate(int offset, int size) { - if (in_progress) { - want_abort = 1; - } else { - CPRINTF("[%T hash abort]\n"); - want_abort = 0; - data_size = 0; - hash = NULL; - } + /* Don't invalidate if passed an invalid region */ + if (offset < 0 || size <= 0 || offset + size < 0) + return 0; + + /* Don't invalidate if hash is already invalid */ + if (!hash) + return 0; + + /* No overlap if passed region is off either end of hashed region */ + if (offset + size <= data_offset || offset >= data_offset + data_size) + return 0; + + /* Invalidate the hash */ + CPRINTF("[%T hash invalidated 0x%08x 0x%08x]\n", offset, size); + vboot_hash_abort(); + return 1; } +/*****************************************************************************/ +/* Hooks */ + static void vboot_hash_init(void) { #ifdef CONFIG_SAVE_VBOOT_HASH @@ -117,72 +183,7 @@ static void vboot_hash_init(void) NULL, 0); } } - -int vboot_hash_invalidate(int offset, int size) -{ - /* Don't invalidate if passed an invalid region */ - if (offset < 0 || size <= 0 || offset + size < 0) - return 0; - - /* Don't invalidate if hash is already invalid */ - if (!hash) - return 0; - - /* No overlap if passed region is off either end of hashed region */ - if (offset + size <= data_offset || offset >= data_offset + data_size) - return 0; - - /* Invalidate the hash */ - CPRINTF("[%T hash invalidated 0x%08x 0x%08x]\n", offset, size); - vboot_hash_abort(); - return 1; -} - -void vboot_hash_task(void) -{ - vboot_hash_init(); - - while (1) { - if (!in_progress) { - /* Nothing to do, so go back to sleep */ - task_wait_event(-1); - } else if (want_abort) { - /* Abort hash computation currently in progress */ - in_progress = 0; - vboot_hash_abort(); - } else { - /* Compute the next chunk of hash */ - int size = MIN(CHUNK_SIZE, data_size - curr_pos); - - SHA256_update(&ctx, - (const uint8_t *)(CONFIG_FLASH_BASE + - data_offset + curr_pos), - size); - curr_pos += size; - if (curr_pos >= data_size) { - /* Store the final hash */ - hash = SHA256_final(&ctx); - CPRINTF("[%T hash done %.*h]\n", - SHA256_DIGEST_SIZE, hash); - - in_progress = 0; - - /* Handle receiving abort during finalize */ - if (want_abort) - vboot_hash_abort(); - } - - /* - * Let other tasks (really, just the watchdog task) - * run for a bit. - */ - usleep(100); - } - } -} - -/*****************************************************************************/ -/* Hooks */ +DECLARE_HOOK(HOOK_INIT, vboot_hash_init, HOOK_PRIO_DEFAULT); #ifdef CONFIG_SAVE_VBOOT_HASH |