1 files changed, 243 insertions, 0 deletions
diff --git a/src/modules/rlm_cache/serialize.c b/src/modules/rlm_cache/serialize.c
new file mode 100644
index 0000000..b1f8e0c
--- /dev/null
+++ b/src/modules/rlm_cache/serialize.c
@@ -0,0 +1,243 @@
+/*
+ *   This program is is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or (at
+ *   your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+/**
+ * $Id$
+ * @file serialize.c
+ * @brief Serialize and deserialise cache entries.
+ *
+ * @author Arran Cudbard-Bell
+ * @copyright 2014 Arran Cudbard-Bell <a.cudbardb@freeradius.org>
+ * @copyright 2014 The FreeRADIUS server project
+ */
+RCSID("$Id$")
+
+#include "rlm_cache.h"
+#include "serialize.h"
+
+/** Serialize a cache entry as a humanly readable string
+ *
+ * @param ctx to alloc new string in. Should be a talloc pool a little bigger
+ *	than the maximum serialized size of the entry.
+ * @param out Where to write pointer to serialized cache entry.
+ * @param c Cache entry to serialize.
+ * @return 0 on success else -1.
+ */
+int cache_serialize(TALLOC_CTX *ctx, char **out, rlm_cache_entry_t *c)
+{
+	TALLOC_CTX *pairs = NULL;
+
+	vp_cursor_t cursor;
+	VALUE_PAIR *vp;
+
+	char *to_store = NULL, *pair;
+
+	to_store = talloc_asprintf(ctx, "&Cache-Expires = %" PRIu64 "\n&Cache-Created = %" PRIu64 "\n",
+				   (uint64_t)c->expires, (uint64_t)c->created);
+	if (!to_store) goto error;
+
+	/*
+	 *	It's valid to have an empty cache entry (save allocing the
+	 *	pairs pool)
+	 */
+	if (!c->control && !c->packet && !c->reply) goto finish;
+
+	/*
+	 *  In the majority of cases using these pools reduces the number of mallocs
+	 *  to two, except in the case where the total serialized pairs length is
+	 *  greater than the pairs pool, or the total serialized string is greater
+	 *  than the store pool.
+	 */
+	pairs = talloc_pool(ctx, 512);
+	if (!pairs) {
+	error:
+		talloc_free(pairs);
+		return -1;
+	}
+
+	if (c->control) {
+		for (vp = fr_cursor_init(&cursor, &c->control);
+		     vp;
+		     vp = fr_cursor_next(&cursor)) {
+			pair = vp_aprints(pairs, vp, '\'');
+			if (!pair) goto error;
+
+			to_store = talloc_asprintf_append_buffer(to_store, "&control:%s\n", pair);
+			if (!to_store) goto error;
+		}
+	}
+
+	if (c->packet) {
+		for (vp = fr_cursor_init(&cursor, &c->packet);
+		     vp;
+		     vp = fr_cursor_next(&cursor)) {
+			pair = vp_aprints(pairs, vp, '\'');
+			if (!pair) goto error;
+
+			to_store = talloc_asprintf_append_buffer(to_store, "&%s\n", pair);
+			if (!to_store) goto error;
+		}
+	}
+
+	if (c->reply) {
+		for (vp = fr_cursor_init(&cursor, &c->reply);
+		     vp;
+		     vp = fr_cursor_next(&cursor)) {
+			pair = vp_aprints(pairs, vp, '\'');
+			if (!pair) goto error;
+
+			to_store = talloc_asprintf_append_buffer(to_store, "&reply:%s\n", pair);
+			if (!to_store) goto error;
+		}
+	}
+
+	if (c->state) {
+		for (vp = fr_cursor_init(&cursor, &c->state);
+		     vp;
+		     vp = fr_cursor_next(&cursor)) {
+			pair = vp_aprints(pairs, vp, '\'');
+			if (!pair) goto error;
+
+			to_store = talloc_asprintf_append_buffer(to_store, "&session-state:%s\n", pair);
+			if (!to_store) goto error;
+		}
+	}
+
+finish:
+	talloc_free(pairs);
+	*out = to_store;
+
+	return 0;
+}
+
+/** Converts a serialized cache entry back into a structure
+ *
+ * @param c Cache entry to populate (should already be allocated)
+ * @param in String representation of cache entry.
+ * @param inlen Length of string. May be < 0 in which case strlen will be
+ *	used to calculate the length of the string.
+ * @return 0 on success, -1 on error.
+ */
+int cache_deserialize(rlm_cache_entry_t *c, char *in, ssize_t inlen)
+{
+	vp_cursor_t packet, control, reply, state;
+
+	TALLOC_CTX *store = NULL;
+	char *p, *q;
+
+	store = talloc_pool(c, 1024);
+	if (!store) return -1;
+
+	if (inlen < 0) inlen = strlen(in);
+
+	fr_cursor_init(&packet, &c->packet);
+	fr_cursor_init(&control, &c->control);
+	fr_cursor_init(&reply, &c->reply);
+	fr_cursor_init(&state, &c->state);
+
+	p = in;
+
+	while (((size_t)(p - in)) < (size_t)inlen) {
+		vp_map_t *map = NULL;
+		VALUE_PAIR *vp = NULL;
+		ssize_t len;
+
+		q = strchr(p, '\n');
+		if (!q) break;	/* List should also be terminated with a \n */
+		*q = '\0';
+
+		if (map_afrom_attr_str(store, &map, p,
+				       REQUEST_CURRENT, PAIR_LIST_REQUEST,
+				       REQUEST_CURRENT, PAIR_LIST_REQUEST) < 0) {
+			fr_strerror_printf("Failed parsing pair: %s", p);
+			goto error;
+		}
+
+		if (map->lhs->type != TMPL_TYPE_ATTR) {
+			fr_strerror_printf("Pair left hand side \"%s\" parsed as %s, needed attribute.  "
+					   "Check local dictionaries", map->lhs->name,
+					   fr_int2str(tmpl_names, map->lhs->type, "<INVALID>"));
+			goto error;
+		}
+
+		if (map->rhs->type != TMPL_TYPE_LITERAL) {
+			fr_strerror_printf("Pair right hand side \"%s\" parsed as %s, needed literal.  "
+					   "Check serialized data quoting", map->rhs->name,
+					   fr_int2str(tmpl_names, map->rhs->type, "<INVALID>"));
+			goto error;
+		}
+
+		/*
+		 *	Convert literal to a type appropriate for the VP.
+		 */
+		if (tmpl_cast_in_place(map->rhs, map->lhs->tmpl_da->type, map->lhs->tmpl_da) < 0) goto error;
+
+		vp = fr_pair_afrom_da(c, map->lhs->tmpl_da);
+		len = value_data_copy(vp, &vp->data, map->rhs->tmpl_data_type,
+				      &map->rhs->tmpl_data_value, map->rhs->tmpl_data_length);
+		if (len < 0) goto error;
+		vp->vp_length = len;
+
+		/*
+		 *	Pull out the special attributes, and set the
+		 *	relevant cache entry fields.
+		 */
+		if (vp->da->vendor == 0) switch (vp->da->attr) {
+		case PW_CACHE_CREATED:
+			c->created = vp->vp_date;
+			talloc_free(vp);
+			goto next;
+
+		case PW_CACHE_EXPIRES:
+			c->expires = vp->vp_date;
+			talloc_free(vp);
+			goto next;
+
+		default:
+			break;
+		}
+
+		switch (map->lhs->tmpl_list) {
+		case PAIR_LIST_REQUEST:
+			fr_cursor_insert(&packet, vp);
+			break;
+
+		case PAIR_LIST_CONTROL:
+			fr_cursor_insert(&control, vp);
+			break;
+
+		case PAIR_LIST_REPLY:
+			fr_cursor_insert(&reply, vp);
+			break;
+
+		case PAIR_LIST_STATE:
+			fr_cursor_insert(&state, vp);
+			break;
+
+		default:
+			fr_strerror_printf("Invalid cache list for pair: %s", p);
+		error:
+			talloc_free(vp);
+			talloc_free(map);
+			return -1;
+		}
+	next:
+		p = q + 1;
+		talloc_free(map);
+	}
+
+	return 0;
+}