Introduce common code for an associative container. This common code
will be used for maps of matches, targets and tables. Hash search tables
from libc are used as an index. The supported set of operations is:
insert, update and find.
Signed-off-by: Dmitrii Banshchikov <me@xxxxxxxxxxxxx>
---
net/bpfilter/Makefile | 2 +-
net/bpfilter/map-common.c | 64 +++++++++++++++++++
net/bpfilter/map-common.h | 19 ++++++
.../testing/selftests/bpf/bpfilter/.gitignore | 1 +
tools/testing/selftests/bpf/bpfilter/Makefile | 2 +
.../testing/selftests/bpf/bpfilter/test_map.c | 63 ++++++++++++++++++
6 files changed, 150 insertions(+), 1 deletion(-)
create mode 100644 net/bpfilter/map-common.c
create mode 100644 net/bpfilter/map-common.h
create mode 100644 tools/testing/selftests/bpf/bpfilter/test_map.c
diff --git a/net/bpfilter/Makefile b/net/bpfilter/Makefile
index 69a6c139fc7a..908fbad680ec 100644
--- a/net/bpfilter/Makefile
+++ b/net/bpfilter/Makefile
@@ -4,7 +4,7 @@
#
userprogs := bpfilter_umh
-bpfilter_umh-objs := main.o bflog.o io.o
+bpfilter_umh-objs := main.o bflog.o io.o map-common.o
userccflags += -I $(srctree)/tools/include/ -I $(srctree)/tools/include/uapi
ifeq ($(CONFIG_BPFILTER_UMH), y)
diff --git a/net/bpfilter/map-common.c b/net/bpfilter/map-common.c
new file mode 100644
index 000000000000..6a4ab0c5d3ec
--- /dev/null
+++ b/net/bpfilter/map-common.c
@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2021 Telegram FZ-LLC
+ */
+
+#include "map-common.h"
+
+#include <linux/err.h>
+
+#include <errno.h>
+#include <string.h>
+
+int create_map(struct hsearch_data *htab, size_t nelem)
+{
+ memset(htab, 0, sizeof(*htab));
+ if (!hcreate_r(nelem, htab))
+ return -errno;
+
+ return 0;
+}
+
+void *map_find(struct hsearch_data *htab, const char *name)
+{
+ const ENTRY needle = { .key = (char *)name };
+ ENTRY *found;
+
+ if (!hsearch_r(needle, FIND, &found, htab))
+ return ERR_PTR(-ENOENT);
+
+ return found->data;
+}
+
+int map_update(struct hsearch_data *htab, const char *name, void *data)
+{
+ const ENTRY needle = { .key = (char *)name, .data = data };
+ ENTRY *found;
+
+ if (!hsearch_r(needle, ENTER, &found, htab))
+ return -errno;
+
+ found->key = (char *)name;
+ found->data = data;
+
+ return 0;
+}
+
+int map_insert(struct hsearch_data *htab, const char *name, void *data)
+{
+ const ENTRY needle = { .key = (char *)name, .data = data };
+ ENTRY *found;
+
+ if (!hsearch_r(needle, ENTER, &found, htab))
+ return -errno;
+
+ if (found->data != data)
+ return -EEXIST;
+
+ return 0;
+}
+
+void free_map(struct hsearch_data *htab)
+{
+ hdestroy_r(htab);
+}
diff --git a/net/bpfilter/map-common.h b/net/bpfilter/map-common.h
new file mode 100644
index 000000000000..b29829230eff
--- /dev/null
+++ b/net/bpfilter/map-common.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2021 Telegram FZ-LLC
+ */
+
+#ifndef NET_BPFILTER_MAP_COMMON_H
+#define NET_BPFILTER_MAP_COMMON_H
+
+#define _GNU_SOURCE
+
+#include <search.h>
+
+int create_map(struct hsearch_data *htab, size_t nelem);
+void *map_find(struct hsearch_data *htab, const char *name);
+int map_insert(struct hsearch_data *htab, const char *name, void *data);
+int map_update(struct hsearch_data *htab, const char *name, void *data);
+void free_map(struct hsearch_data *htab);
+
+#endif // NET_BPFILTER_MAP_COMMON_H
diff --git a/tools/testing/selftests/bpf/bpfilter/.gitignore b/tools/testing/selftests/bpf/bpfilter/.gitignore
index f5785e366013..be10b50ca289 100644
--- a/tools/testing/selftests/bpf/bpfilter/.gitignore
+++ b/tools/testing/selftests/bpf/bpfilter/.gitignore
@@ -1,2 +1,3 @@
# SPDX-License-Identifier: GPL-2.0-only
test_io
+test_map
diff --git a/tools/testing/selftests/bpf/bpfilter/Makefile b/tools/testing/selftests/bpf/bpfilter/Makefile
index c02d72d89199..77afbbdf27c5 100644
--- a/tools/testing/selftests/bpf/bpfilter/Makefile
+++ b/tools/testing/selftests/bpf/bpfilter/Makefile
@@ -9,9 +9,11 @@ BPFILTERSRCDIR := $(top_srcdir)/net/bpfilter
CFLAGS += -Wall -g -pthread -I$(TOOLSINCDIR) -I$(APIDIR) -I$(BPFILTERSRCDIR)
TEST_GEN_PROGS += test_io
+TEST_GEN_PROGS += test_map
KSFT_KHDR_INSTALL := 1
include ../../lib.mk
$(OUTPUT)/test_io: test_io.c $(BPFILTERSRCDIR)/io.c
+$(OUTPUT)/test_map: test_map.c $(BPFILTERSRCDIR)/map-common.c
diff --git a/tools/testing/selftests/bpf/bpfilter/test_map.c b/tools/testing/selftests/bpf/bpfilter/test_map.c
new file mode 100644
index 000000000000..6ac61a634e41
--- /dev/null
+++ b/tools/testing/selftests/bpf/bpfilter/test_map.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "map-common.h"
+
+#include <linux/err.h>
+
+#include "../../kselftest_harness.h"
+
+FIXTURE(test_map)
+{
+ struct hsearch_data map;
+ const char *key;
+ void *expected;
+ void *actual;
+};
+
+FIXTURE_SETUP(test_map)
+{
+ const int max_nelements = 100;
+
+ create_map(&self->map, max_nelements);
+ self->key = "key";
+ self->expected = "expected";
+ self->actual = "actual";
+}
+
+FIXTURE_TEARDOWN(test_map)
+{
+ free_map(&self->map);
+}
+
+TEST_F(test_map, insert_and_find)
+{
+ void *found;
+
+ found = map_find(&self->map, self->key);
+ ASSERT_TRUE(IS_ERR(found))
+ ASSERT_EQ(-ENOENT, PTR_ERR(found))
+
+ ASSERT_EQ(0, map_insert(&self->map, self->key, self->expected));
+ ASSERT_EQ(0, map_insert(&self->map, self->key, self->expected));
+ ASSERT_EQ(-EEXIST, map_insert(&self->map, self->key, self->actual));
+
+ found = map_find(&self->map, self->key);
+
+ ASSERT_FALSE(IS_ERR(found));
+ ASSERT_STREQ(self->expected, found);
+}
+
+TEST_F(test_map, update)
+{
+ void *found;
+
+ ASSERT_EQ(0, map_insert(&self->map, self->key, self->actual));
+ ASSERT_EQ(0, map_update(&self->map, self->key, self->expected));
+
+ found = map_find(&self->map, self->key);
+
+ ASSERT_FALSE(IS_ERR(found));
+ ASSERT_STREQ(self->expected, found);
+}
+
+TEST_HARNESS_MAIN
--
2.25.1
