1 files changed, 97 insertions, 0 deletions
diff --git a/src/libsystemd/sd-netlink/generic-netlink.c b/src/libsystemd/sd-netlink/generic-netlink.c
new file mode 100644
index 0000000..3445757
--- /dev/null
+++ b/src/libsystemd/sd-netlink/generic-netlink.c
@@ -0,0 +1,97 @@
+#include <linux/genetlink.h>
+
+#include "sd-netlink.h"
+#include "netlink-internal.h"
+#include "alloc-util.h"
+
+typedef struct {
+        const char* name;
+        uint8_t version;
+} genl_family;
+
+static const genl_family genl_families[] = {
+        [SD_GENL_ID_CTRL] = { .name = "", .version = 1 },
+        [SD_GENL_WIREGUARD] = { .name = "wireguard", .version = 1 },
+        [SD_GENL_FOU]       = { .name = "fou", .version = 1 },
+};
+
+int sd_genl_socket_open(sd_netlink **ret) {
+        return netlink_open_family(ret, NETLINK_GENERIC);
+}
+static int lookup_id(sd_netlink *nl, sd_genl_family family, uint16_t *id);
+
+static int genl_message_new(sd_netlink *nl, sd_genl_family family, uint16_t nlmsg_type, uint8_t cmd, sd_netlink_message **ret) {
+        int r;
+        struct genlmsghdr *genl;
+        const NLType *genl_cmd_type, *nl_type;
+        const NLTypeSystem *type_system;
+        size_t size;
+        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
+
+        assert_return(nl->protocol == NETLINK_GENERIC, -EINVAL);
+
+        r = type_system_get_type(&genl_family_type_system_root, &genl_cmd_type, family);
+        if (r < 0)
+                return r;
+
+        r = message_new_empty(nl, &m);
+        if (r < 0)
+                return r;
+
+        size = NLMSG_SPACE(sizeof(struct genlmsghdr));
+        m->hdr = malloc0(size);
+        if (!m->hdr)
+                return -ENOMEM;
+
+        m->hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
+
+        type_get_type_system(genl_cmd_type, &type_system);
+
+        r = type_system_get_type(type_system, &nl_type, cmd);
+        if (r < 0)
+                return r;
+
+        m->hdr->nlmsg_len = size;
+        m->hdr->nlmsg_type = nlmsg_type;
+
+        type_get_type_system(nl_type, &m->containers[0].type_system);
+        genl = NLMSG_DATA(m->hdr);
+        genl->cmd = cmd;
+        genl->version = genl_families[family].version;
+
+        *ret = TAKE_PTR(m);
+
+        return 0;
+}
+
+int sd_genl_message_new(sd_netlink *nl, sd_genl_family family, uint8_t cmd, sd_netlink_message **ret) {
+        int r;
+        uint16_t id = GENL_ID_CTRL;
+
+        if (family != SD_GENL_ID_CTRL) {
+                r = lookup_id(nl, family, &id);
+                if (r < 0)
+                        return r;
+        }
+
+        return genl_message_new(nl, family, id, cmd, ret);
+}
+
+static int lookup_id(sd_netlink *nl, sd_genl_family family, uint16_t *id) {
+        int r;
+        _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *req = NULL, *reply = NULL;
+
+        r = sd_genl_message_new(nl, SD_GENL_ID_CTRL, CTRL_CMD_GETFAMILY, &req);
+        if (r < 0)
+                return r;
+
+        r = sd_netlink_message_append_string(req, CTRL_ATTR_FAMILY_NAME, genl_families[family].name);
+        if (r < 0)
+                return r;
+
+        r = sd_netlink_call(nl, req, 0, &reply);
+        if (r < 0)
+                return r;
+
+        return sd_netlink_message_read_u16(reply, CTRL_ATTR_FAMILY_ID, id);
+}