[RFC PATCH 07/12] net/filter: Introduce filter-ubpf module

[Zhang Chen <chen.zhang@intel.com>]

The filter-ubpf module able to load user defined ebpf program
to handle network packet based on filter framework.

Signed-off-by: Zhang Chen <chen.zhang@intel.com>
---
 net/filter-ubpf.c | 149 ++++++++++++++++++++++++++++++++++++++++++++++
 net/meson.build   |   1 +
 2 files changed, 150 insertions(+)
 create mode 100644 net/filter-ubpf.c

diff --git a/net/filter-ubpf.c b/net/filter-ubpf.c
new file mode 100644
index 0000000000..c63a021759
--- /dev/null
+++ b/net/filter-ubpf.c
@@ -0,0 +1,149 @@
+/*
+ * QEMU Userspace eBPF Support
+ *
+ * Copyright(C) 2022 Intel Corporation.
+ *
+ * Author:
+ *  Zhang Chen <chen.zhang@intel.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "net/filter.h"
+#include "net/net.h"
+#include "qapi/error.h"
+#include "qom/object.h"
+#include "qemu/main-loop.h"
+#include "qemu/error-report.h"
+#include "trace.h"
+#include "ebpf/ubpf.h"
+
+#define TYPE_FILTER_UBPF "filter-ubpf"
+OBJECT_DECLARE_SIMPLE_TYPE(FiliterUbpfState, FILTER_UBPF)
+
+struct FiliterUbpfState {
+    NetFilterState parent_obj;
+    bool ip_mode;
+    char *handler;
+    UbpfState ubpf;
+};
+
+static ssize_t filter_ubpf_receive_iov(NetFilterState *nf,
+                                       NetClientState *sender,
+                                       unsigned flags,
+                                       const struct iovec *iov,
+                                       int iovcnt,
+                                       NetPacketSent *sent_cb)
+{
+    /* TODO: handle packet by loaded userspace ebpf program */
+
+    return 0;
+}
+
+static void filter_ubpf_cleanup(NetFilterState *nf)
+{
+    /* cleanup */
+}
+
+static void filter_ubpf_setup(NetFilterState *nf, Error **errp)
+{
+    FiliterUbpfState *s = FILTER_UBPF(nf);
+
+    if (s->handler == NULL) {
+        error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND, "filter-ubpf parameter"\
+                  " 'ubpf-handler' cannot be empty");
+        return;
+    }
+
+    qemu_ubpf_init_jit(&s->ubpf, true);
+
+    if (qemu_ubpf_prepare(&s->ubpf, s->handler)) {
+        error_set(errp, ERROR_CLASS_DEVICE_NOT_ACTIVE, "filter-ubpf parameter"\
+                  " 'ubpf-handler' cannot be load");
+        return;
+    }
+}
+
+static char *filter_ubpf_get_handler(Object *obj, Error **errp)
+{
+    FiliterUbpfState *s = FILTER_UBPF(obj);
+
+    return g_strdup(s->handler);
+}
+
+static void filter_ubpf_set_handler(Object *obj,
+                                    const char *value,
+                                    Error **errp)
+{
+    FiliterUbpfState *s = FILTER_UBPF(obj);
+
+    g_free(s->handler);
+    s->handler = g_strdup(value);
+    if (!s->handler) {
+        error_setg(errp, "filter ubpf needs 'ubpf-handler' "
+                   "property set");
+        return;
+    }
+}
+
+static bool filter_ubpf_get_mode(Object *obj, Error **errp)
+{
+    FiliterUbpfState *s = FILTER_UBPF(obj);
+
+    return s->ip_mode;
+}
+
+static void filter_ubpf_set_mode(Object *obj, bool value, Error **errp)
+{
+    FiliterUbpfState *s = FILTER_UBPF(obj);
+
+    s->ip_mode = value;
+}
+
+static void filter_ubpf_class_init(ObjectClass *oc, void *data)
+{
+    NetFilterClass *nfc = NETFILTER_CLASS(oc);
+
+    object_class_property_add_str(oc, "ubpf-handler",
+                                  filter_ubpf_get_handler,
+                                  filter_ubpf_set_handler);
+    object_class_property_add_bool(oc, "ip-mode",
+                                   filter_ubpf_get_mode,
+                                   filter_ubpf_set_mode);
+
+    nfc->setup = filter_ubpf_setup;
+    nfc->cleanup = filter_ubpf_cleanup;
+    nfc->receive_iov = filter_ubpf_receive_iov;
+}
+
+static void filter_ubpf_init(Object *obj)
+{
+    FiliterUbpfState *s = FILTER_UBPF(obj);
+
+    /* Filter-ubpf default is ip_mode */
+    s->ip_mode = true;
+}
+
+static void filter_ubpf_fini(Object *obj)
+{
+    /* do some thing */
+}
+
+static const TypeInfo filter_ubpf_info = {
+    .name = TYPE_FILTER_UBPF,
+    .parent = TYPE_NETFILTER,
+    .class_init = filter_ubpf_class_init,
+    .instance_init = filter_ubpf_init,
+    .instance_finalize = filter_ubpf_fini,
+    .instance_size = sizeof(FiliterUbpfState),
+};
+
+static void register_types(void)
+{
+    type_register_static(&filter_ubpf_info);
+}
+
+type_init(register_types);
diff --git a/net/meson.build b/net/meson.build
index 754e2d1d40..177078fa7a 100644
--- a/net/meson.build
+++ b/net/meson.build
@@ -14,6 +14,7 @@ softmmu_ss.add(files(
   'queue.c',
   'socket.c',
   'util.c',
+  'filter-ubpf.c',
 ))
 
 softmmu_ss.add(when: 'CONFIG_TCG', if_true: files('filter-replay.c'))
-- 
2.25.1