Add CRYPTO_BUFFER and CRYPTO_BUFFER_POOL.
These structures allow for blobs of data (e.g. certificates) to be
deduplicated in memory.
Change-Id: Iebfec90b85d55565848a178b6951562b4ccc083e
Reviewed-on: https://boringssl-review.googlesource.com/11820
Reviewed-by: Adam Langley <alangley@gmail.com>
Commit-Queue: Adam Langley <alangley@gmail.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
diff --git a/crypto/pool/CMakeLists.txt b/crypto/pool/CMakeLists.txt
new file mode 100644
index 0000000..fe55af2
--- /dev/null
+++ b/crypto/pool/CMakeLists.txt
@@ -0,0 +1,20 @@
+include_directories(../../include)
+
+add_library(
+ pool
+
+ OBJECT
+
+ pool.c
+)
+
+add_executable(
+ pool_test
+
+ pool_test.cc
+
+ $<TARGET_OBJECTS:test_support>
+)
+
+target_link_libraries(pool_test crypto)
+add_dependencies(all_tests pool_test)
diff --git a/crypto/pool/internal.h b/crypto/pool/internal.h
new file mode 100644
index 0000000..3ec2ec2
--- /dev/null
+++ b/crypto/pool/internal.h
@@ -0,0 +1,45 @@
+/* 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. */
+
+#ifndef OPENSSL_HEADER_POOL_INTERNAL_H
+#define OPENSSL_HEADER_POOL_INTERNAL_H
+
+#include <openssl/lhash.h>
+#include <openssl/thread.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+
+DECLARE_LHASH_OF(CRYPTO_BUFFER);
+
+struct crypto_buffer_st {
+ CRYPTO_BUFFER_POOL *pool;
+ uint8_t *data;
+ size_t len;
+ CRYPTO_refcount_t references;
+};
+
+struct crypto_buffer_pool_st {
+ LHASH_OF(CRYPTO_BUFFER) *bufs;
+ CRYPTO_MUTEX lock;
+};
+
+
+#if defined(__cplusplus)
+} /* extern C */
+#endif
+
+#endif /* OPENSSL_HEADER_POOL_INTERNAL_H */
diff --git a/crypto/pool/pool.c b/crypto/pool/pool.c
new file mode 100644
index 0000000..ebe1b24
--- /dev/null
+++ b/crypto/pool/pool.c
@@ -0,0 +1,200 @@
+/* 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 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;
+ }
+
+ 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;
+ }
+ 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;
+}
+
+const 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);
+}
diff --git a/crypto/pool/pool_test.cc b/crypto/pool/pool_test.cc
new file mode 100644
index 0000000..4dfc546
--- /dev/null
+++ b/crypto/pool/pool_test.cc
@@ -0,0 +1,85 @@
+/* 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 <string.h>
+
+#include <openssl/pool.h>
+
+
+static bool TestUnpooled() {
+ static const uint8_t kData[4] = {1, 2, 3, 4};
+ bssl::UniquePtr<CRYPTO_BUFFER> buf(
+ CRYPTO_BUFFER_new(kData, sizeof(kData), nullptr));
+ if (!buf) {
+ return false;
+ }
+
+ if (CRYPTO_BUFFER_len(buf.get()) != sizeof(kData) ||
+ memcmp(kData, CRYPTO_BUFFER_data(buf.get()), sizeof(kData)) != 0) {
+ fprintf(stderr, "CRYPTO_BUFFER corrupted data.\n");
+ return false;
+ }
+
+ CRYPTO_BUFFER_up_ref(buf.get());
+ bssl::UniquePtr<CRYPTO_BUFFER> buf2(buf.get());
+
+ return true;
+}
+
+static bool TestEmpty() {
+ bssl::UniquePtr<CRYPTO_BUFFER> buf(CRYPTO_BUFFER_new(nullptr, 0, nullptr));
+ if (!buf) {
+ return false;
+ }
+
+ return true;
+}
+
+static bool TestPool() {
+ bssl::UniquePtr<CRYPTO_BUFFER_POOL> pool(CRYPTO_BUFFER_POOL_new());
+ if (!pool) {
+ return false;
+ }
+
+ static const uint8_t kData[4] = {1, 2, 3, 4};
+ bssl::UniquePtr<CRYPTO_BUFFER> buf(
+ CRYPTO_BUFFER_new(kData, sizeof(kData), pool.get()));
+ if (!buf) {
+ return false;
+ }
+
+ bssl::UniquePtr<CRYPTO_BUFFER> buf2(
+ CRYPTO_BUFFER_new(kData, sizeof(kData), pool.get()));
+ if (!buf2) {
+ return false;
+ }
+
+ if (buf.get() != buf2.get()) {
+ fprintf(stderr, "CRYPTO_BUFFER_POOL did not dedup data.\n");
+ return false;
+ }
+
+ return true;
+}
+
+int main(int argc, char **argv) {
+ if (!TestUnpooled() ||
+ !TestEmpty() ||
+ !TestPool()) {
+ return 1;
+ }
+
+ printf("PASS\n");
+ return 0;
+}
