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Convert rand code to new threading API

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Replace the CRYPTO_LOCK_RAND and CRYPTO_LOCK_RAND2 locks with new thread
API style locks.

Reviewed-by: Rich Salz <rsalz@openssl.org>
This commit is contained in:
Matt Caswell
2016-03-08 11:40:05 +00:00
parent 29eed3ddb8
commit 8eed7e873b
2 changed files with 47 additions and 34 deletions
Download Patch File Download Diff File Expand all files Collapse all files

79
crypto/rand/md_rand.c
View File

@@ -125,6 +125,7 @@
#include <openssl/rand.h>
#include <openssl/async.h>
#include "rand_lcl.h"
#include "internal/threads.h"
#include <openssl/err.h>
@@ -147,12 +148,15 @@ static long md_count[2] = { 0, 0 };
static double entropy = 0;
static int initialized = 0;
static unsigned int crypto_lock_rand = 0; /* may be set only when a thread
* holds CRYPTO_LOCK_RAND (to
* prevent double locking) */
/* access to lockin_thread is synchronized by CRYPTO_LOCK_RAND2 */
static CRYPTO_RWLOCK *rand_lock = NULL;
static CRYPTO_RWLOCK *rand_tmp_lock = NULL;
static CRYPTO_ONCE rand_lock_init = CRYPTO_ONCE_STATIC_INIT;
/* May be set only when a thread holds rand_lock (to prevent double locking) */
static unsigned int crypto_lock_rand = 0;
/* access to locking_threadid is synchronized by rand_tmp_lock */
/* valid iff crypto_lock_rand is set */
static CRYPTO_THREADID locking_threadid;
static CRYPTO_THREAD_ID locking_threadid;
#ifdef PREDICT
int rand_predictable = 0;
@@ -183,6 +187,12 @@ static RAND_METHOD rand_meth = {
rand_status
};
static void do_rand_lock_init(void)
{
rand_lock = CRYPTO_THREAD_lock_new();
rand_tmp_lock = CRYPTO_THREAD_lock_new();
}
RAND_METHOD *RAND_OpenSSL(void)
{
return (&rand_meth);
@@ -198,6 +208,8 @@ static void rand_cleanup(void)
md_count[1] = 0;
entropy = 0;
initialized = 0;
CRYPTO_THREAD_lock_free(rand_lock);
CRYPTO_THREAD_lock_free(rand_tmp_lock);
}
static int rand_add(const void *buf, int num, double add)
@@ -231,18 +243,19 @@ static int rand_add(const void *buf, int num, double add)
if (m == NULL)
goto err;
CRYPTO_THREAD_run_once(&rand_lock_init, do_rand_lock_init);
/* check if we already have the lock */
if (crypto_lock_rand) {
CRYPTO_THREADID cur;
CRYPTO_THREADID_current(&cur);
CRYPTO_r_lock(CRYPTO_LOCK_RAND2);
do_not_lock = !CRYPTO_THREADID_cmp(&locking_threadid, &cur);
CRYPTO_r_unlock(CRYPTO_LOCK_RAND2);
CRYPTO_THREAD_ID cur = CRYPTO_THREAD_get_current_id();
CRYPTO_THREAD_read_lock(rand_tmp_lock);
do_not_lock = CRYPTO_THREAD_compare_id(locking_threadid, cur);
CRYPTO_THREAD_unlock(rand_tmp_lock);
} else
do_not_lock = 0;
if (!do_not_lock)
CRYPTO_w_lock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_write_lock(rand_lock);
st_idx = state_index;
/*
@@ -274,7 +287,7 @@ static int rand_add(const void *buf, int num, double add)
md_count[1] += (num / MD_DIGEST_LENGTH) + (num % MD_DIGEST_LENGTH > 0);
if (!do_not_lock)
CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_unlock(rand_lock);
for (i = 0; i < num; i += MD_DIGEST_LENGTH) {
j = (num - i);
@@ -328,7 +341,7 @@ static int rand_add(const void *buf, int num, double add)
}
if (!do_not_lock)
CRYPTO_w_lock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_write_lock(rand_lock);
/*
* Don't just copy back local_md into md -- this could mean that other
* thread's seeding remains without effect (except for the incremented
@@ -341,7 +354,7 @@ static int rand_add(const void *buf, int num, double add)
if (entropy < ENTROPY_NEEDED) /* stop counting when we have enough */
entropy += add;
if (!do_not_lock)
CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_unlock(rand_lock);
rv = 1;
err:
@@ -428,7 +441,8 @@ static int rand_bytes(unsigned char *buf, int num, int pseudo)
* global 'md'.
*/
CRYPTO_w_lock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_run_once(&rand_lock_init, do_rand_lock_init);
CRYPTO_THREAD_write_lock(rand_lock);
/*
* We could end up in an async engine while holding this lock so ensure
* we don't pause and cause a deadlock
@@ -436,9 +450,9 @@ static int rand_bytes(unsigned char *buf, int num, int pseudo)
ASYNC_block_pause();
/* prevent rand_bytes() from trying to obtain the lock again */
CRYPTO_w_lock(CRYPTO_LOCK_RAND2);
CRYPTO_THREADID_current(&locking_threadid);
CRYPTO_w_unlock(CRYPTO_LOCK_RAND2);
CRYPTO_THREAD_write_lock(rand_tmp_lock);
locking_threadid = CRYPTO_THREAD_get_current_id();
CRYPTO_THREAD_unlock(rand_tmp_lock);
crypto_lock_rand = 1;
if (!initialized) {
@@ -513,7 +527,7 @@ static int rand_bytes(unsigned char *buf, int num, int pseudo)
/* before unlocking, we must clear 'crypto_lock_rand' */
crypto_lock_rand = 0;
ASYNC_unblock_pause();
CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_unlock(rand_lock);
while (num > 0) {
/* num_ceil -= MD_DIGEST_LENGTH/2 */
@@ -566,17 +580,17 @@ static int rand_bytes(unsigned char *buf, int num, int pseudo)
|| !MD_Update(m, (unsigned char *)&(md_c[0]), sizeof(md_c))
|| !MD_Update(m, local_md, MD_DIGEST_LENGTH))
goto err;
CRYPTO_w_lock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_write_lock(rand_lock);
/*
* Prevent deadlocks if we end up in an async engine
*/
ASYNC_block_pause();
if (!MD_Update(m, md, MD_DIGEST_LENGTH) || !MD_Final(m, md)) {
CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_unlock(rand_lock);
goto err;
}
ASYNC_unblock_pause();
CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_unlock(rand_lock);
EVP_MD_CTX_free(m);
if (ok)
@@ -617,24 +631,25 @@ static int rand_pseudo_bytes(unsigned char *buf, int num)
static int rand_status(void)
{
CRYPTO_THREADID cur;
CRYPTO_THREAD_ID cur;
int ret;
int do_not_lock;
CRYPTO_THREADID_current(&cur);
CRYPTO_THREAD_run_once(&rand_lock_init, do_rand_lock_init);
cur = CRYPTO_THREAD_get_current_id();
/*
* check if we already have the lock (could happen if a RAND_poll()
* implementation calls RAND_status())
*/
if (crypto_lock_rand) {
CRYPTO_r_lock(CRYPTO_LOCK_RAND2);
do_not_lock = !CRYPTO_THREADID_cmp(&locking_threadid, &cur);
CRYPTO_r_unlock(CRYPTO_LOCK_RAND2);
CRYPTO_THREAD_read_lock(rand_tmp_lock);
do_not_lock = CRYPTO_THREAD_compare_id(locking_threadid, cur);
CRYPTO_THREAD_unlock(rand_tmp_lock);
} else
do_not_lock = 0;
if (!do_not_lock) {
CRYPTO_w_lock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_write_lock(rand_lock);
/*
* Prevent deadlocks in case we end up in an async engine
*/
@@ -643,9 +658,9 @@ static int rand_status(void)
/*
* prevent rand_bytes() from trying to obtain the lock again
*/
CRYPTO_w_lock(CRYPTO_LOCK_RAND2);
CRYPTO_THREADID_cpy(&locking_threadid, &cur);
CRYPTO_w_unlock(CRYPTO_LOCK_RAND2);
CRYPTO_THREAD_write_lock(rand_tmp_lock);
locking_threadid = cur;
CRYPTO_THREAD_unlock(rand_tmp_lock);
crypto_lock_rand = 1;
}
@@ -661,7 +676,7 @@ static int rand_status(void)
crypto_lock_rand = 0;
ASYNC_unblock_pause();
CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
CRYPTO_THREAD_unlock(rand_lock);
}
return ret;

2
include/openssl/crypto.h
View File

@@ -166,8 +166,6 @@ extern "C" {
*/
# define CRYPTO_LOCK_X509_STORE 11
# define CRYPTO_LOCK_RAND 18
# define CRYPTO_LOCK_RAND2 19
# define CRYPTO_LOCK_DYNLOCK 29
# define CRYPTO_LOCK_ENGINE 30
# define CRYPTO_LOCK_ECDSA 32