diff options
Diffstat (limited to 'drivers/char/random.c')
| -rw-r--r-- | drivers/char/random.c | 24 |
1 files changed, 12 insertions, 12 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 2d5daf9b58e9..54d020815b4e 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -904,7 +904,7 @@ static void extract_buf(struct entropy_store *r, __u8 *out) int i; union { __u32 w[5]; - unsigned long l[LONGS(EXTRACT_SIZE)]; + unsigned long l[LONGS(20)]; } hash; __u32 workspace[SHA_WORKSPACE_WORDS]; __u8 extract[64]; @@ -917,6 +917,17 @@ static void extract_buf(struct entropy_store *r, __u8 *out) sha_transform(hash.w, (__u8 *)(r->pool + i), workspace); /* + * If we have a architectural hardware random number + * generator, mix that in, too. + */ + for (i = 0; i < LONGS(20); i++) { + unsigned long v; + if (!arch_get_random_long(&v)) + break; + hash.l[i] ^= v; + } + + /* * We mix the hash back into the pool to prevent backtracking * attacks (where the attacker knows the state of the pool * plus the current outputs, and attempts to find previous @@ -945,17 +956,6 @@ static void extract_buf(struct entropy_store *r, __u8 *out) hash.w[1] ^= hash.w[4]; hash.w[2] ^= rol32(hash.w[2], 16); - /* - * If we have a architectural hardware random number - * generator, mix that in, too. - */ - for (i = 0; i < LONGS(EXTRACT_SIZE); i++) { - unsigned long v; - if (!arch_get_random_long(&v)) - break; - hash.l[i] ^= v; - } - memcpy(out, &hash, EXTRACT_SIZE); memset(&hash, 0, sizeof(hash)); } |
