diff options
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/random.c | 40 |
1 files changed, 27 insertions, 13 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index b86eae9b77df..85e81ec1451e 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -399,7 +399,6 @@ static DECLARE_WAIT_QUEUE_HEAD(random_read_wait); static DECLARE_WAIT_QUEUE_HEAD(random_write_wait); static struct fasync_struct *fasync; -#if 0 static bool debug; module_param(debug, bool, 0644); #define DEBUG_ENT(fmt, arg...) do { \ @@ -410,9 +409,6 @@ module_param(debug, bool, 0644); blocking_pool.entropy_count,\ nonblocking_pool.entropy_count,\ ## arg); } while (0) -#else -#define DEBUG_ENT(fmt, arg...) do {} while (0) -#endif /********************************************************************** * @@ -437,6 +433,7 @@ struct entropy_store { int entropy_count; int entropy_total; unsigned int initialized:1; + bool last_data_init; __u8 last_data[EXTRACT_SIZE]; }; @@ -829,7 +826,7 @@ static void xfer_secondary_pool(struct entropy_store *r, size_t nbytes) bytes = min_t(int, bytes, sizeof(tmp)); DEBUG_ENT("going to reseed %s with %d bits " - "(%d of %d requested)\n", + "(%zu of %d requested)\n", r->name, bytes * 8, nbytes * 8, r->entropy_count); bytes = extract_entropy(r->pull, tmp, bytes, @@ -860,7 +857,7 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min, spin_lock_irqsave(&r->lock, flags); BUG_ON(r->entropy_count > r->poolinfo->POOLBITS); - DEBUG_ENT("trying to extract %d bits from %s\n", + DEBUG_ENT("trying to extract %zu bits from %s\n", nbytes * 8, r->name); /* Can we pull enough? */ @@ -882,7 +879,7 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min, } } - DEBUG_ENT("debiting %d entropy credits from %s%s\n", + DEBUG_ENT("debiting %zu entropy credits from %s%s\n", nbytes * 8, r->name, r->limit ? "" : " (unlimited)"); spin_unlock_irqrestore(&r->lock, flags); @@ -957,6 +954,10 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf, ssize_t ret = 0, i; __u8 tmp[EXTRACT_SIZE]; + /* if last_data isn't primed, we need EXTRACT_SIZE extra bytes */ + if (fips_enabled && !r->last_data_init) + nbytes += EXTRACT_SIZE; + trace_extract_entropy(r->name, nbytes, r->entropy_count, _RET_IP_); xfer_secondary_pool(r, nbytes); nbytes = account(r, nbytes, min, reserved); @@ -967,6 +968,17 @@ static ssize_t extract_entropy(struct entropy_store *r, void *buf, if (fips_enabled) { unsigned long flags; + + /* prime last_data value if need be, per fips 140-2 */ + if (!r->last_data_init) { + spin_lock_irqsave(&r->lock, flags); + memcpy(r->last_data, tmp, EXTRACT_SIZE); + r->last_data_init = true; + nbytes -= EXTRACT_SIZE; + spin_unlock_irqrestore(&r->lock, flags); + extract_buf(r, tmp); + } + spin_lock_irqsave(&r->lock, flags); if (!memcmp(tmp, r->last_data, EXTRACT_SIZE)) panic("Hardware RNG duplicated output!\n"); @@ -1086,6 +1098,7 @@ static void init_std_data(struct entropy_store *r) r->entropy_count = 0; r->entropy_total = 0; + r->last_data_init = false; mix_pool_bytes(r, &now, sizeof(now), NULL); for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof(rv)) { if (!arch_get_random_long(&rv)) @@ -1142,11 +1155,16 @@ random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) if (n > SEC_XFER_SIZE) n = SEC_XFER_SIZE; - DEBUG_ENT("reading %d bits\n", n*8); + DEBUG_ENT("reading %zu bits\n", n*8); n = extract_entropy_user(&blocking_pool, buf, n); - DEBUG_ENT("read got %d bits (%d still needed)\n", + if (n < 0) { + retval = n; + break; + } + + DEBUG_ENT("read got %zd bits (%zd still needed)\n", n*8, (nbytes-n)*8); if (n == 0) { @@ -1171,10 +1189,6 @@ random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) continue; } - if (n < 0) { - retval = n; - break; - } count += n; buf += n; nbytes -= n; |
