blob: 44d10af6280390fa76d452496dd8a6076ecdb93b [file] [log] [blame]
/* Copyright (c) 2016, Google Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
#include <openssl/pool.h>
#include <assert.h>
#include <string.h>
#include <openssl/buf.h>
#include <openssl/bytestring.h>
#include <openssl/mem.h>
#include <openssl/thread.h>
#include "../internal.h"
#include "internal.h"
static uint32_t CRYPTO_BUFFER_hash(const CRYPTO_BUFFER *buf) {
return OPENSSL_hash32(buf->data, buf->len);
}
static int CRYPTO_BUFFER_cmp(const CRYPTO_BUFFER *a, const CRYPTO_BUFFER *b) {
if (a->len != b->len) {
return 1;
}
return OPENSSL_memcmp(a->data, b->data, a->len);
}
CRYPTO_BUFFER_POOL* CRYPTO_BUFFER_POOL_new(void) {
CRYPTO_BUFFER_POOL *pool = OPENSSL_malloc(sizeof(CRYPTO_BUFFER_POOL));
if (pool == NULL) {
return NULL;
}
OPENSSL_memset(pool, 0, sizeof(CRYPTO_BUFFER_POOL));
pool->bufs = lh_CRYPTO_BUFFER_new(CRYPTO_BUFFER_hash, CRYPTO_BUFFER_cmp);
if (pool->bufs == NULL) {
OPENSSL_free(pool);
return NULL;
}
CRYPTO_MUTEX_init(&pool->lock);
return pool;
}
void CRYPTO_BUFFER_POOL_free(CRYPTO_BUFFER_POOL *pool) {
if (pool == NULL) {
return;
}
#if !defined(NDEBUG)
CRYPTO_MUTEX_lock_write(&pool->lock);
assert(lh_CRYPTO_BUFFER_num_items(pool->bufs) == 0);
CRYPTO_MUTEX_unlock_write(&pool->lock);
#endif
lh_CRYPTO_BUFFER_free(pool->bufs);
CRYPTO_MUTEX_cleanup(&pool->lock);
OPENSSL_free(pool);
}
CRYPTO_BUFFER *CRYPTO_BUFFER_new(const uint8_t *data, size_t len,
CRYPTO_BUFFER_POOL *pool) {
if (pool != NULL) {
CRYPTO_BUFFER tmp;
tmp.data = (uint8_t *) data;
tmp.len = len;
CRYPTO_MUTEX_lock_read(&pool->lock);
CRYPTO_BUFFER *const duplicate =
lh_CRYPTO_BUFFER_retrieve(pool->bufs, &tmp);
if (duplicate != NULL) {
CRYPTO_refcount_inc(&duplicate->references);
}
CRYPTO_MUTEX_unlock_read(&pool->lock);
if (duplicate != NULL) {
return duplicate;
}
}
CRYPTO_BUFFER *const buf = OPENSSL_malloc(sizeof(CRYPTO_BUFFER));
if (buf == NULL) {
return NULL;
}
OPENSSL_memset(buf, 0, sizeof(CRYPTO_BUFFER));
buf->data = BUF_memdup(data, len);
if (len != 0 && buf->data == NULL) {
OPENSSL_free(buf);
return NULL;
}
buf->len = len;
buf->references = 1;
if (pool == NULL) {
return buf;
}
buf->pool = pool;
CRYPTO_MUTEX_lock_write(&pool->lock);
CRYPTO_BUFFER *duplicate = lh_CRYPTO_BUFFER_retrieve(pool->bufs, buf);
int inserted = 0;
if (duplicate == NULL) {
CRYPTO_BUFFER *old = NULL;
inserted = lh_CRYPTO_BUFFER_insert(pool->bufs, &old, buf);
assert(old == NULL);
} else {
CRYPTO_refcount_inc(&duplicate->references);
}
CRYPTO_MUTEX_unlock_write(&pool->lock);
if (!inserted) {
/* We raced to insert |buf| into the pool and lost, or else there was an
* error inserting. */
OPENSSL_free(buf->data);
OPENSSL_free(buf);
return duplicate;
}
return buf;
}
CRYPTO_BUFFER* CRYPTO_BUFFER_new_from_CBS(CBS *cbs, CRYPTO_BUFFER_POOL *pool) {
return CRYPTO_BUFFER_new(CBS_data(cbs), CBS_len(cbs), pool);
}
void CRYPTO_BUFFER_free(CRYPTO_BUFFER *buf) {
if (buf == NULL) {
return;
}
CRYPTO_BUFFER_POOL *const pool = buf->pool;
if (pool == NULL) {
if (CRYPTO_refcount_dec_and_test_zero(&buf->references)) {
/* If a reference count of zero is observed, there cannot be a reference
* from any pool to this buffer and thus we are able to free this
* buffer. */
OPENSSL_free(buf->data);
OPENSSL_free(buf);
}
return;
}
CRYPTO_MUTEX_lock_write(&pool->lock);
if (!CRYPTO_refcount_dec_and_test_zero(&buf->references)) {
CRYPTO_MUTEX_unlock_write(&buf->pool->lock);
return;
}
/* We have an exclusive lock on the pool, therefore no concurrent lookups can
* find this buffer and increment the reference count. Thus, if the count is
* zero there are and can never be any more references and thus we can free
* this buffer. */
void *found = lh_CRYPTO_BUFFER_delete(pool->bufs, buf);
assert(found != NULL);
assert(found == buf);
(void)found;
CRYPTO_MUTEX_unlock_write(&buf->pool->lock);
OPENSSL_free(buf->data);
OPENSSL_free(buf);
}
int CRYPTO_BUFFER_up_ref(CRYPTO_BUFFER *buf) {
/* This is safe in the case that |buf->pool| is NULL because it's just
* standard reference counting in that case.
*
* This is also safe if |buf->pool| is non-NULL because, if it were racing
* with |CRYPTO_BUFFER_free| then the two callers must have independent
* references already and so the reference count will never hit zero. */
CRYPTO_refcount_inc(&buf->references);
return 1;
}
const uint8_t *CRYPTO_BUFFER_data(const CRYPTO_BUFFER *buf) {
return buf->data;
}
size_t CRYPTO_BUFFER_len(const CRYPTO_BUFFER *buf) {
return buf->len;
}
void CRYPTO_BUFFER_init_CBS(const CRYPTO_BUFFER *buf, CBS *out) {
CBS_init(out, buf->data, buf->len);
}