lib: Add namemap_cache

A few functions to maintain lookupname and lookupsid cache in gencache.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=13369

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>

3 files changed, 369 insertions, 0 deletions

diff --git a/source3/lib/namemap_cache.c b/source3/lib/namemap_cache.c
new file mode 100644
index 00000000000..0d6ed32abc5
--- /dev/null
+++ b/source3/lib/namemap_cache.c
@@ -0,0 +1,323 @@
+/*
+ * Unix SMB/CIFS implementation.
+ * Utils for caching sid2name and name2sid
+ * Copyright (C) Volker Lendecke 2017
+ *
+ * This program 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "replace.h"
+#include "namemap_cache.h"
+#include "source3/lib/gencache.h"
+#include "lib/util/debug.h"
+#include "lib/util/strv.h"
+#include "lib/util/talloc_stack.h"
+#include "lib/util/charset/charset.h"
+#include "libcli/security/dom_sid.h"
+
+bool namemap_cache_set_sid2name(const struct dom_sid *sid,
+				const char *domain, const char *name,
+				enum lsa_SidType type, time_t timeout)
+{
+	char typebuf[16];
+	char sidbuf[DOM_SID_STR_BUFLEN];
+	char keybuf[DOM_SID_STR_BUFLEN+10];
+	char *val = NULL;
+	DATA_BLOB data;
+	int ret;
+	bool ok = false;
+
+	if ((sid == NULL) || is_null_sid(sid)) {
+		return true;
+	}
+	if (domain == NULL) {
+		domain = "";
+	}
+	if (name == NULL) {
+		name = "";
+	}
+	if (type == SID_NAME_UNKNOWN) {
+		domain = "";
+		name = "";
+	}
+
+	snprintf(typebuf, sizeof(typebuf), "%d", (int)type);
+	snprintf(keybuf, sizeof(keybuf), "SID2NAME/%s", sidbuf);
+
+	ret = strv_add(talloc_tos(), &val, domain);
+	if (ret != 0) {
+		DBG_DEBUG("strv_add failed: %s\n", strerror(ret));
+		goto fail;
+	}
+	ret = strv_add(NULL, &val, name);
+	if (ret != 0) {
+		DBG_DEBUG("strv_add failed: %s\n", strerror(ret));
+		goto fail;
+	}
+	ret = strv_add(NULL, &val, typebuf);
+	if (ret != 0) {
+		DBG_DEBUG("strv_add failed: %s\n", strerror(ret));
+		goto fail;
+	}
+
+	dom_sid_string_buf(sid, sidbuf, sizeof(sidbuf));
+	snprintf(keybuf, sizeof(keybuf), "SID2NAME/%s", sidbuf);
+
+	data = data_blob_const(val, talloc_get_size(val));
+
+	ok = gencache_set_data_blob(keybuf, data, timeout);
+	if (!ok) {
+		DBG_DEBUG("gencache_set_data_blob failed\n");
+	}
+fail:
+	TALLOC_FREE(val);
+	return ok;
+}
+
+struct namemap_cache_find_sid_state {
+	void (*fn)(const char *domain, const char *name,
+		   enum lsa_SidType type, time_t timeout,
+		   void *private_data);
+	void *private_data;
+	bool ok;
+};
+
+static void namemap_cache_find_sid_parser(time_t timeout, DATA_BLOB blob,
+					  void *private_data)
+{
+	struct namemap_cache_find_sid_state *state = private_data;
+	const char *strv = (const char *)blob.data;
+	size_t strv_len = blob.length;
+	const char *domain;
+	const char *name;
+	const char *typebuf;
+	char *endptr;
+	unsigned long type;
+
+	state->ok = false;
+
+	domain = strv_len_next(strv, strv_len, NULL);
+	if (domain == NULL) {
+		return;
+	}
+	name = strv_len_next(strv, strv_len, domain);
+	if (name == NULL) {
+		return;
+	}
+	typebuf = strv_len_next(strv, strv_len, name);
+	if (typebuf == NULL) {
+		return;
+	}
+
+	type = strtoul(typebuf, &endptr, 10);
+	if (*endptr != '\0') {
+		return;
+	}
+	if ((type == ULONG_MAX) && (errno == ERANGE)) {
+		return;
+	}
+
+	state->fn(domain, name, (enum lsa_SidType)type, timeout,
+		  state->private_data);
+
+	state->ok = true;
+}
+
+bool namemap_cache_find_sid(const struct dom_sid *sid,
+			    void (*fn)(const char *domain, const char *name,
+				       enum lsa_SidType type, time_t timeout,
+				       void *private_data),
+			    void *private_data)
+{
+	struct namemap_cache_find_sid_state state = {
+		.fn = fn, .private_data = private_data
+	};
+	char sidbuf[DOM_SID_STR_BUFLEN];
+	char keybuf[DOM_SID_STR_BUFLEN+10];
+	bool ok;
+
+	dom_sid_string_buf(sid, sidbuf, sizeof(sidbuf));
+	snprintf(keybuf, sizeof(keybuf), "SID2NAME/%s", sidbuf);
+
+	ok = gencache_parse(keybuf, namemap_cache_find_sid_parser, &state);
+	if (!ok) {
+		DBG_DEBUG("gencache_parse(%s) failed\n", keybuf);
+		return false;
+	}
+
+	if (!state.ok) {
+		DBG_DEBUG("Could not parse %s, deleting\n", keybuf);
+		gencache_del(keybuf);
+		return false;
+	}
+
+	return true;
+}
+
+bool namemap_cache_set_name2sid(const char *domain, const char *name,
+				const struct dom_sid *sid,
+				enum lsa_SidType type,
+				time_t timeout)
+{
+	char typebuf[16];
+	char sidbuf[DOM_SID_STR_BUFLEN];
+	char *key;
+	char *key_upper;
+	char *val = NULL;
+	DATA_BLOB data;
+	int ret;
+	bool ok = false;
+
+	if (domain == NULL) {
+		domain = "";
+	}
+	if (name == NULL) {
+		name = "";
+	}
+	if (type == SID_NAME_UNKNOWN) {
+		sidbuf[0] = '\0';
+	} else {
+		dom_sid_string_buf(sid, sidbuf, sizeof(sidbuf));
+	}
+
+	snprintf(typebuf, sizeof(typebuf), "%d", (int)type);
+
+	key = talloc_asprintf(talloc_tos(), "NAME2SID/%s\\%s", domain, name);
+	if (key == NULL) {
+		DBG_DEBUG("talloc_asprintf failed\n");
+		goto fail;
+	}
+	key_upper = strupper_talloc(key, key);
+	if (key_upper == NULL) {
+		DBG_DEBUG("strupper_talloc failed\n");
+		goto fail;
+	}
+
+	ret = strv_add(key, &val, sidbuf);
+	if (ret != 0) {
+		DBG_DEBUG("strv_add failed: %s\n", strerror(ret));
+		goto fail;
+	}
+	ret = strv_add(NULL, &val, typebuf);
+	if (ret != 0) {
+		DBG_DEBUG("strv_add failed: %s\n", strerror(ret));
+		goto fail;
+	}
+
+	data = data_blob_const(val, talloc_get_size(val));
+
+	ok = gencache_set_data_blob(key_upper, data, timeout);
+	if (!ok) {
+		DBG_DEBUG("gencache_set_data_blob failed\n");
+	}
+fail:
+	TALLOC_FREE(key);
+	return ok;
+}
+
+struct namemap_cache_find_name_state {
+	void (*fn)(const struct dom_sid *sid,
+		   enum lsa_SidType type, time_t timeout,
+		   void *private_data);
+	void *private_data;
+	bool ok;
+};
+
+static void namemap_cache_find_name_parser(time_t timeout, DATA_BLOB blob,
+					   void *private_data)
+{
+	struct namemap_cache_find_name_state *state = private_data;
+	const char *strv = (const char *)blob.data;
+	size_t strv_len = blob.length;
+	const char *sidbuf;
+	const char *sid_endptr;
+	const char *typebuf;
+	char *endptr;
+	struct dom_sid sid;
+	unsigned long type;
+	bool ok;
+
+	state->ok = false;
+
+	sidbuf = strv_len_next(strv, strv_len, NULL);
+	if (sidbuf == NULL) {
+		return;
+	}
+	typebuf = strv_len_next(strv, strv_len, sidbuf);
+	if (typebuf == NULL) {
+		return;
+	}
+
+	ok = dom_sid_parse_endp(sidbuf, &sid, &sid_endptr);
+	if (!ok) {
+		return;
+	}
+	if (*sid_endptr != '\0') {
+		return;
+	}
+
+	type = strtoul(typebuf, &endptr, 10);
+	if (*endptr != '\0') {
+		return;
+	}
+	if ((type == ULONG_MAX) && (errno == ERANGE)) {
+		return;
+	}
+
+	state->fn(&sid, (enum lsa_SidType)type, timeout, state->private_data);
+
+	state->ok = true;
+}
+
+bool namemap_cache_find_name(const char *domain, const char *name,
+			     void (*fn)(const struct dom_sid *sid,
+					enum lsa_SidType type, time_t timeout,
+					void *private_data),
+			     void *private_data)
+{
+	struct namemap_cache_find_name_state state = {
+		.fn = fn, .private_data = private_data
+	};
+	char *key;
+	char *key_upper;
+	bool ret = false;
+	bool ok;
+
+	key = talloc_asprintf(talloc_tos(), "NAME2SID/%s\\%s", domain, name);
+	if (key == NULL) {
+		DBG_DEBUG("talloc_asprintf failed\n");
+		return false;
+	}
+	key_upper = strupper_talloc(key, key);
+	if (key_upper == NULL) {
+		DBG_DEBUG("strupper_talloc failed\n");
+		goto fail;
+	}
+
+	ok = gencache_parse(key_upper, namemap_cache_find_name_parser, &state);
+	if (!ok) {
+		DBG_DEBUG("gencache_parse(%s) failed\n", key_upper);
+		goto fail;
+	}
+
+	if (!state.ok) {
+		DBG_DEBUG("Could not parse %s, deleting\n", key_upper);
+		goto fail;
+	}
+
+	ret = true;
+fail:
+	TALLOC_FREE(key);
+	return ret;
+}
diff --git a/source3/lib/namemap_cache.h b/source3/lib/namemap_cache.h
new file mode 100644
index 00000000000..a70de34b885
--- /dev/null
+++ b/source3/lib/namemap_cache.h
@@ -0,0 +1,45 @@
+/*
+ * Unix SMB/CIFS implementation.
+ * Utils for caching sid2name and name2sid
+ * Copyright (C) Volker Lendecke 2017
+ *
+ * This program 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __LIB_NAMEMAP_CACHE_H__
+#define __LIB_NAMEMAP_CACHE_H__
+
+#include "lib/util/time.h"
+#include "lib/util/data_blob.h"
+#include "librpc/gen_ndr/lsa.h"
+
+bool namemap_cache_set_sid2name(const struct dom_sid *sid,
+				const char *domain, const char *name,
+				enum lsa_SidType type, time_t timeout);
+bool namemap_cache_set_name2sid(const char *domain, const char *name,
+				const struct dom_sid *sid,
+				enum lsa_SidType type,
+				time_t timeout);
+bool namemap_cache_find_sid(const struct dom_sid *sid,
+			    void (*fn)(const char *domain, const char *name,
+				       enum lsa_SidType type, time_t timeout,
+				       void *private_data),
+			    void *private_data);
+bool namemap_cache_find_name(const char *domain, const char *name,
+			     void (*fn)(const struct dom_sid *sid,
+					enum lsa_SidType type, time_t timeout,
+					void *private_data),
+			     void *private_data);
+
+#endif
diff --git a/source3/wscript_build b/source3/wscript_build
index 8b119a824c3..cc511c376d8 100644
--- a/source3/wscript_build
+++ b/source3/wscript_build
@@ -410,6 +410,7 @@ bld.SAMBA3_SUBSYSTEM('samba3core',
                           lib/audit.c
                           lib/tevent_wait.c
                           lib/idmap_cache.c
+                          lib/namemap_cache.c
                           lib/util_ea.c
                           lib/background.c
                           lib/cleanupdb.c