1 files changed, 143 insertions, 0 deletions
diff --git a/crypto/property/defn_cache.c b/crypto/property/defn_cache.c
new file mode 100644
index 000000000000..b43f2d247ef6
--- /dev/null
+++ b/crypto/property/defn_cache.c
@@ -0,0 +1,143 @@
+/*
+ * Copyright 2019-2022 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright (c) 2019, Oracle and/or its affiliates.  All rights reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <string.h>
+#include <openssl/err.h>
+#include <openssl/lhash.h>
+#include "internal/propertyerr.h"
+#include "internal/property.h"
+#include "internal/core.h"
+#include "property_local.h"
+
+/*
+ * Implement a property definition cache.
+ * These functions assume that they are called under a write lock.
+ * No attempt is made to clean out the cache, except when it is shut down.
+ */
+
+typedef struct {
+    const char *prop;
+    OSSL_PROPERTY_LIST *defn;
+    char body[1];
+} PROPERTY_DEFN_ELEM;
+
+DEFINE_LHASH_OF(PROPERTY_DEFN_ELEM);
+
+static unsigned long property_defn_hash(const PROPERTY_DEFN_ELEM *a)
+{
+    return OPENSSL_LH_strhash(a->prop);
+}
+
+static int property_defn_cmp(const PROPERTY_DEFN_ELEM *a,
+                             const PROPERTY_DEFN_ELEM *b)
+{
+    return strcmp(a->prop, b->prop);
+}
+
+static void property_defn_free(PROPERTY_DEFN_ELEM *elem)
+{
+    ossl_property_free(elem->defn);
+    OPENSSL_free(elem);
+}
+
+static void property_defns_free(void *vproperty_defns)
+{
+    LHASH_OF(PROPERTY_DEFN_ELEM) *property_defns = vproperty_defns;
+
+    if (property_defns != NULL) {
+        lh_PROPERTY_DEFN_ELEM_doall(property_defns,
+                                    &property_defn_free);
+        lh_PROPERTY_DEFN_ELEM_free(property_defns);
+    }
+}
+
+static void *property_defns_new(OSSL_LIB_CTX *ctx) {
+    return lh_PROPERTY_DEFN_ELEM_new(&property_defn_hash, &property_defn_cmp);
+}
+
+static const OSSL_LIB_CTX_METHOD property_defns_method = {
+    OSSL_LIB_CTX_METHOD_DEFAULT_PRIORITY,
+    property_defns_new,
+    property_defns_free,
+};
+
+OSSL_PROPERTY_LIST *ossl_prop_defn_get(OSSL_LIB_CTX *ctx, const char *prop)
+{
+    PROPERTY_DEFN_ELEM elem, *r;
+    LHASH_OF(PROPERTY_DEFN_ELEM) *property_defns;
+
+    property_defns = ossl_lib_ctx_get_data(ctx,
+                                           OSSL_LIB_CTX_PROPERTY_DEFN_INDEX,
+                                           &property_defns_method);
+    if (property_defns == NULL || !ossl_lib_ctx_read_lock(ctx))
+        return NULL;
+
+    elem.prop = prop;
+    r = lh_PROPERTY_DEFN_ELEM_retrieve(property_defns, &elem);
+    ossl_lib_ctx_unlock(ctx);
+    if (r == NULL || !ossl_assert(r->defn != NULL))
+        return NULL;
+    return r->defn;
+}
+
+/*
+ * Cache the property list for a given property string *pl.
+ * If an entry already exists in the cache *pl is freed and
+ * overwritten with the existing entry from the cache.
+ */
+int ossl_prop_defn_set(OSSL_LIB_CTX *ctx, const char *prop,
+                       OSSL_PROPERTY_LIST **pl)
+{
+    PROPERTY_DEFN_ELEM elem, *old, *p = NULL;
+    size_t len;
+    LHASH_OF(PROPERTY_DEFN_ELEM) *property_defns;
+    int res = 1;
+
+    property_defns = ossl_lib_ctx_get_data(ctx,
+                                           OSSL_LIB_CTX_PROPERTY_DEFN_INDEX,
+                                           &property_defns_method);
+    if (property_defns == NULL)
+        return 0;
+
+    if (prop == NULL)
+        return 1;
+
+    if (!ossl_lib_ctx_write_lock(ctx))
+        return 0;
+    elem.prop = prop;
+    if (pl == NULL) {
+        lh_PROPERTY_DEFN_ELEM_delete(property_defns, &elem);
+        goto end;
+    }
+    /* check if property definition is in the cache already */
+    if ((p = lh_PROPERTY_DEFN_ELEM_retrieve(property_defns, &elem)) != NULL) {
+        ossl_property_free(*pl);
+        *pl = p->defn;
+        goto end;
+    }
+    len = strlen(prop);
+    p = OPENSSL_malloc(sizeof(*p) + len);
+    if (p != NULL) {
+        p->prop = p->body;
+        p->defn = *pl;
+        memcpy(p->body, prop, len + 1);
+        old = lh_PROPERTY_DEFN_ELEM_insert(property_defns, p);
+        if (!ossl_assert(old == NULL))
+            /* This should not happen. An existing entry is handled above. */
+            goto end;
+        if (!lh_PROPERTY_DEFN_ELEM_error(property_defns))
+            goto end;
+    }
+    OPENSSL_free(p);
+    res = 0;
+ end:
+    ossl_lib_ctx_unlock(ctx);
+    return res;
+}