diff options
Diffstat (limited to 'drivers/char/random.c')
-rw-r--r-- | drivers/char/random.c | 41 |
1 files changed, 21 insertions, 20 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 38f2fab29c56..5f22a08101f6 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -309,11 +309,11 @@ static void crng_reseed(struct work_struct *work) * key value, at index 4, so the state should always be zeroed out * immediately after using in order to maintain forward secrecy. * If the state cannot be erased in a timely manner, then it is - * safer to set the random_data parameter to &chacha_state[4] so - * that this function overwrites it before returning. + * safer to set the random_data parameter to &chacha_state->x[4] + * so that this function overwrites it before returning. */ static void crng_fast_key_erasure(u8 key[CHACHA_KEY_SIZE], - u32 chacha_state[CHACHA_STATE_WORDS], + struct chacha_state *chacha_state, u8 *random_data, size_t random_data_len) { u8 first_block[CHACHA_BLOCK_SIZE]; @@ -321,8 +321,8 @@ static void crng_fast_key_erasure(u8 key[CHACHA_KEY_SIZE], BUG_ON(random_data_len > 32); chacha_init_consts(chacha_state); - memcpy(&chacha_state[4], key, CHACHA_KEY_SIZE); - memset(&chacha_state[12], 0, sizeof(u32) * 4); + memcpy(&chacha_state->x[4], key, CHACHA_KEY_SIZE); + memset(&chacha_state->x[12], 0, sizeof(u32) * 4); chacha20_block(chacha_state, first_block); memcpy(key, first_block, CHACHA_KEY_SIZE); @@ -335,7 +335,7 @@ static void crng_fast_key_erasure(u8 key[CHACHA_KEY_SIZE], * random data. It also returns up to 32 bytes on its own of random data * that may be used; random_data_len may not be greater than 32. */ -static void crng_make_state(u32 chacha_state[CHACHA_STATE_WORDS], +static void crng_make_state(struct chacha_state *chacha_state, u8 *random_data, size_t random_data_len) { unsigned long flags; @@ -395,7 +395,7 @@ static void crng_make_state(u32 chacha_state[CHACHA_STATE_WORDS], static void _get_random_bytes(void *buf, size_t len) { - u32 chacha_state[CHACHA_STATE_WORDS]; + struct chacha_state chacha_state; u8 tmp[CHACHA_BLOCK_SIZE]; size_t first_block_len; @@ -403,26 +403,26 @@ static void _get_random_bytes(void *buf, size_t len) return; first_block_len = min_t(size_t, 32, len); - crng_make_state(chacha_state, buf, first_block_len); + crng_make_state(&chacha_state, buf, first_block_len); len -= first_block_len; buf += first_block_len; while (len) { if (len < CHACHA_BLOCK_SIZE) { - chacha20_block(chacha_state, tmp); + chacha20_block(&chacha_state, tmp); memcpy(buf, tmp, len); memzero_explicit(tmp, sizeof(tmp)); break; } - chacha20_block(chacha_state, buf); - if (unlikely(chacha_state[12] == 0)) - ++chacha_state[13]; + chacha20_block(&chacha_state, buf); + if (unlikely(chacha_state.x[12] == 0)) + ++chacha_state.x[13]; len -= CHACHA_BLOCK_SIZE; buf += CHACHA_BLOCK_SIZE; } - memzero_explicit(chacha_state, sizeof(chacha_state)); + chacha_zeroize_state(&chacha_state); } /* @@ -441,7 +441,7 @@ EXPORT_SYMBOL(get_random_bytes); static ssize_t get_random_bytes_user(struct iov_iter *iter) { - u32 chacha_state[CHACHA_STATE_WORDS]; + struct chacha_state chacha_state; u8 block[CHACHA_BLOCK_SIZE]; size_t ret = 0, copied; @@ -453,21 +453,22 @@ static ssize_t get_random_bytes_user(struct iov_iter *iter) * bytes, in case userspace causes copy_to_iter() below to sleep * forever, so that we still retain forward secrecy in that case. */ - crng_make_state(chacha_state, (u8 *)&chacha_state[4], CHACHA_KEY_SIZE); + crng_make_state(&chacha_state, (u8 *)&chacha_state.x[4], + CHACHA_KEY_SIZE); /* * However, if we're doing a read of len <= 32, we don't need to * use chacha_state after, so we can simply return those bytes to * the user directly. */ if (iov_iter_count(iter) <= CHACHA_KEY_SIZE) { - ret = copy_to_iter(&chacha_state[4], CHACHA_KEY_SIZE, iter); + ret = copy_to_iter(&chacha_state.x[4], CHACHA_KEY_SIZE, iter); goto out_zero_chacha; } for (;;) { - chacha20_block(chacha_state, block); - if (unlikely(chacha_state[12] == 0)) - ++chacha_state[13]; + chacha20_block(&chacha_state, block); + if (unlikely(chacha_state.x[12] == 0)) + ++chacha_state.x[13]; copied = copy_to_iter(block, sizeof(block), iter); ret += copied; @@ -484,7 +485,7 @@ static ssize_t get_random_bytes_user(struct iov_iter *iter) memzero_explicit(block, sizeof(block)); out_zero_chacha: - memzero_explicit(chacha_state, sizeof(chacha_state)); + chacha_zeroize_state(&chacha_state); return ret ? ret : -EFAULT; } |