Properties for implementation selection.

Properties are a sequence of comma separated name=value pairs.  A name
without a corresponding value is assumed to be a Boolean and have the
true value 'yes'.  Values are either strings or numbers.  Strings can be
quoted either _"_ or _'_ or unquoted (with restrictions).  There are no
escape characters inside strings.  Number are either decimal digits or
'0x' followed by hexidecimal digits.  Numbers are represented internally
as signed sixty four bit values.

Queries on properties are a sequence comma separated conditional tests.
These take the form of name=value (equality test), name!=value (inequality
test) or name (Boolean test for truth).  Queries can be parsed, compared
against a definition or merged pairwise.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/8224)

1 files changed, 105 insertions, 0 deletions

diff --git a/crypto/property/defn_cache.c b/crypto/property/defn_cache.c
new file mode 100644
index 0000000000..df87c19f55
--- /dev/null
+++ b/crypto/property/defn_cache.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright 2019 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 "property_lcl.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 LHASH_OF(PROPERTY_DEFN_ELEM) *property_defns = NULL;
+
+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);
+}
+
+int ossl_prop_defn_init(void)
+{
+    property_defns = lh_PROPERTY_DEFN_ELEM_new(&property_defn_hash,
+                                               &property_defn_cmp);
+    return property_defns != NULL;
+}
+
+void ossl_prop_defn_cleanup(void)
+{
+    if (property_defns != NULL) {
+        lh_PROPERTY_DEFN_ELEM_doall(property_defns, &property_defn_free);
+        lh_PROPERTY_DEFN_ELEM_free(property_defns);
+        property_defns = NULL;
+    }
+}
+
+OSSL_PROPERTY_LIST *ossl_prop_defn_get(const char *prop)
+{
+    PROPERTY_DEFN_ELEM elem, *r;
+
+    elem.prop = prop;
+    r = lh_PROPERTY_DEFN_ELEM_retrieve(property_defns, &elem);
+    return r != NULL ? r->defn : NULL;
+}
+
+int ossl_prop_defn_set(const char *prop, OSSL_PROPERTY_LIST *pl)
+{
+    PROPERTY_DEFN_ELEM elem, *old, *p = NULL;
+    size_t len;
+
+    if (prop == NULL)
+        return 1;
+
+    if (pl == NULL) {
+        elem.prop = prop;
+        lh_PROPERTY_DEFN_ELEM_delete(property_defns, &elem);
+        return 1;
+    }
+    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 (old != NULL) {
+            property_defn_free(old);
+            return 1;
+        }
+        if (!lh_PROPERTY_DEFN_ELEM_error(property_defns))
+            return 1;
+    }
+    OPENSSL_free(p);
+    return 0;
+}