From b96b3aeb4ac1fae68e77bb38a1553855b8ef16f7 Mon Sep 17 00:00:00 2001 From: Rob Austein Date: Fri, 17 Jul 2015 10:54:52 +0200 Subject: First cut at libhal support for hash cores with ability to save and restore internal state. Compiles, not yet tested. --- hash.c | 100 +++++++++++++++++++++++++++++++++++++++++++---------------------- 1 file changed, 67 insertions(+), 33 deletions(-) (limited to 'hash.c') diff --git a/hash.c b/hash.c index f48e079..af461a6 100644 --- a/hash.c +++ b/hash.c @@ -76,7 +76,8 @@ typedef struct { } driver_t; /* - * Hash state. + * Hash state. For now we assume that the only core state we need to + * save and restore is the current digest value. */ typedef struct { @@ -84,7 +85,8 @@ typedef struct { const driver_t *driver; uint64_t msg_length_high; /* Total data hashed in this message */ uint64_t msg_length_low; /* (128 bits in SHA-512 cases) */ - uint8_t block[HAL_MAX_HASH_BLOCK_LENGTH]; /* Block we're accumulating */ + uint8_t block[HAL_MAX_HASH_BLOCK_LENGTH], /* Block we're accumulating */ + core_state[HAL_MAX_HASH_DIGEST_LENGTH]; /* Saved core state */ size_t block_used; /* How much of the block we've used */ unsigned block_count; /* Blocks sent */ } internal_hash_state_t; @@ -185,42 +187,42 @@ const hal_hash_descriptor_t hal_hash_sha1[1] = {{ SHA1_BLOCK_LEN, SHA1_DIGEST_LEN, sizeof(internal_hash_state_t), sizeof(internal_hmac_state_t), dalgid_sha1, sizeof(dalgid_sha1), - &sha1_driver + &sha1_driver, 0 }}; const hal_hash_descriptor_t hal_hash_sha256[1] = {{ SHA256_BLOCK_LEN, SHA256_DIGEST_LEN, sizeof(internal_hash_state_t), sizeof(internal_hmac_state_t), dalgid_sha256, sizeof(dalgid_sha256), - &sha256_driver + &sha256_driver, 1 }}; const hal_hash_descriptor_t hal_hash_sha512_224[1] = {{ SHA512_BLOCK_LEN, SHA512_224_DIGEST_LEN, sizeof(internal_hash_state_t), sizeof(internal_hmac_state_t), dalgid_sha512_224, sizeof(dalgid_sha512_224), - &sha512_224_driver + &sha512_224_driver, 0 }}; const hal_hash_descriptor_t hal_hash_sha512_256[1] = {{ SHA512_BLOCK_LEN, SHA512_256_DIGEST_LEN, sizeof(internal_hash_state_t), sizeof(internal_hmac_state_t), dalgid_sha512_256, sizeof(dalgid_sha512_256), - &sha512_256_driver + &sha512_256_driver, 0 }}; const hal_hash_descriptor_t hal_hash_sha384[1] = {{ SHA512_BLOCK_LEN, SHA384_DIGEST_LEN, sizeof(internal_hash_state_t), sizeof(internal_hmac_state_t), dalgid_sha384, sizeof(dalgid_sha384), - &sha384_driver + &sha384_driver, 0 }}; const hal_hash_descriptor_t hal_hash_sha512[1] = {{ SHA512_BLOCK_LEN, SHA512_DIGEST_LEN, sizeof(internal_hash_state_t), sizeof(internal_hmac_state_t), dalgid_sha512, sizeof(dalgid_sha512), - &sha512_driver + &sha512_driver, 0 }}; /* @@ -281,17 +283,54 @@ hal_error_t hal_hash_initialize(const hal_hash_descriptor_t * const descriptor, memset(state, 0, sizeof(*state)); state->descriptor = descriptor; state->driver = driver; - + opaque_state->state = state; return HAL_OK; } +/* + * Read hash result from core. At least for now, this also serves to + * read current hash state from core. + */ + +static hal_error_t hash_read_digest(const driver_t * const driver, + uint8_t *digest, + const size_t digest_length) +{ + hal_error_t err; + + assert(digest != NULL && digest_length % 4 == 0); + + if ((err = hal_io_wait_valid(driver->status_addr)) != HAL_OK) + return err; + + return hal_io_read(driver->digest_addr, digest, digest_length); +} + +/* + * Write hash state back to core. + */ + +static hal_error_t hash_write_digest(const driver_t * const driver, + const uint8_t * const digest, + const size_t digest_length) +{ + hal_error_t err; + + assert(digest != NULL && digest_length % 4 == 0); + + if ((err = hal_io_wait_ready(driver->status_addr)) != HAL_OK) + return err; + + return hal_io_write(driver->digest_addr, digest, digest_length); +} + /* * Send one block to a core. */ -static hal_error_t hash_write_block(const internal_hash_state_t * const state) +static hal_error_t hash_write_block(internal_hash_state_t *state) { uint8_t ctrl_cmd[4]; hal_error_t err; @@ -299,43 +338,38 @@ static hal_error_t hash_write_block(const internal_hash_state_t * const state) assert(state != NULL && state->descriptor != NULL && state->driver != NULL); assert(state->descriptor->block_length % 4 == 0); + assert(state->descriptor->digest_length <= sizeof(state->core_state) || + !state->descriptor->can_restore_state); + if (debug) fprintf(stderr, "[ %s ]\n", state->block_count == 0 ? "init" : "next"); - if ((err = hal_io_write(state->driver->block_addr, state->block, state->descriptor->block_length)) != HAL_OK) + if ((err = hal_io_wait_ready(state->driver->status_addr)) != HAL_OK) + return err; + + if (state->descriptor->can_restore_state && + state->block_count != 0 && + (err = hash_write_digest(state->driver, state->core_state, + state->descriptor->digest_length)) != HAL_OK) + return err; + + if ((err = hal_io_write(state->driver->block_addr, state->block, + state->descriptor->block_length)) != HAL_OK) return err; ctrl_cmd[0] = ctrl_cmd[1] = ctrl_cmd[2] = 0; ctrl_cmd[3] = state->block_count == 0 ? CTRL_INIT : CTRL_NEXT; ctrl_cmd[3] |= state->driver->ctrl_mode; - /* - * Not sure why we're waiting for ready here, but it's what the old - * (read: tested) code did, so keep that behavior for now. - */ - if ((err = hal_io_write(state->driver->ctrl_addr, ctrl_cmd, sizeof(ctrl_cmd))) != HAL_OK) return err; - return hal_io_wait_valid(state->driver->status_addr); -} - -/* - * Read hash result from core. - */ - -static hal_error_t hash_read_digest(const driver_t * const driver, - uint8_t *digest, - const size_t digest_length) -{ - hal_error_t err; - - assert(digest != NULL && digest_length % 4 == 0); - - if ((err = hal_io_wait_valid(driver->status_addr)) != HAL_OK) + if (state->descriptor->can_restore_state && + (err = hash_read_digest(state->driver, state->core_state, + state->descriptor->digest_length)) != HAL_OK) return err; - return hal_io_read(driver->digest_addr, digest, digest_length); + return hal_io_wait_valid(state->driver->status_addr); } /* -- cgit v1.2.3