/* 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" DEFINE_LHASH_OF(CRYPTO_BUFFER) 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_alloc(uint8_t **out_data, size_t len) { CRYPTO_BUFFER *const buf = OPENSSL_malloc(sizeof(CRYPTO_BUFFER)); if (buf == NULL) { return NULL; } OPENSSL_memset(buf, 0, sizeof(CRYPTO_BUFFER)); buf->data = OPENSSL_malloc(len); if (len != 0 && buf->data == NULL) { OPENSSL_free(buf); return NULL; } buf->len = len; buf->references = 1; *out_data = buf->data; 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); }