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- /* 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);
- }
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