Merge branch 'tools-ynl-user-space-c'

Jakub Kicinski says:

====================
tools: ynl: user space C

Use the code gen which is already in tree to generate a user space
library for a handful of simple families. I find YNL C quite useful
in some WIP projects, and I think others may find it useful, too.
I was hoping someone will pick this work up and finish it...
but it seems that Python YNL has largely stolen the thunder.
Python may not be great for selftest, tho, and actually this lib
is more fully-featured. The Python script was meant as a quick demo,
funny how those things go.

v2: https://lore.kernel.org/all/20230604175843.662084-1-kuba@kernel.org/
v1: https://lore.kernel.org/all/20230603052547.631384-1-kuba@kernel.org/
====================

Link: https://lore.kernel.org/r/20230605190108.809439-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 340 insertions, 0 deletions

diff --git a/tools/net/ynl/generated/fou-user.c b/tools/net/ynl/generated/fou-user.c
new file mode 100644
index 000000000000..c99b5d438021
--- /dev/null
+++ b/tools/net/ynl/generated/fou-user.c
@@ -0,0 +1,340 @@
+// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/fou.yaml */
+/* YNL-GEN user source */
+
+#include <stdlib.h>
+#include "fou-user.h"
+#include "ynl.h"
+#include <linux/fou.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <libmnl/libmnl.h>
+#include <linux/genetlink.h>
+
+/* Enums */
+static const char * const fou_op_strmap[] = {
+	[FOU_CMD_UNSPEC] = "unspec",
+	[FOU_CMD_ADD] = "add",
+	[FOU_CMD_DEL] = "del",
+	[FOU_CMD_GET] = "get",
+};
+
+const char *fou_op_str(int op)
+{
+	if (op < 0 || op >= (int)MNL_ARRAY_SIZE(fou_op_strmap))
+		return NULL;
+	return fou_op_strmap[op];
+}
+
+static const char * const fou_encap_type_strmap[] = {
+	[0] = "unspec",
+	[1] = "direct",
+	[2] = "gue",
+};
+
+const char *fou_encap_type_str(int value)
+{
+	if (value < 0 || value >= (int)MNL_ARRAY_SIZE(fou_encap_type_strmap))
+		return NULL;
+	return fou_encap_type_strmap[value];
+}
+
+/* Policies */
+extern struct ynl_policy_nest fou_nest;
+
+struct ynl_policy_attr fou_policy[FOU_ATTR_MAX + 1] = {
+	[FOU_ATTR_UNSPEC] = { .name = "unspec", .type = YNL_PT_REJECT, },
+	[FOU_ATTR_PORT] = { .name = "port", .type = YNL_PT_U16, },
+	[FOU_ATTR_AF] = { .name = "af", .type = YNL_PT_U8, },
+	[FOU_ATTR_IPPROTO] = { .name = "ipproto", .type = YNL_PT_U8, },
+	[FOU_ATTR_TYPE] = { .name = "type", .type = YNL_PT_U8, },
+	[FOU_ATTR_REMCSUM_NOPARTIAL] = { .name = "remcsum_nopartial", .type = YNL_PT_FLAG, },
+	[FOU_ATTR_LOCAL_V4] = { .name = "local_v4", .type = YNL_PT_U32, },
+	[FOU_ATTR_LOCAL_V6] = { .name = "local_v6", .type = YNL_PT_BINARY,},
+	[FOU_ATTR_PEER_V4] = { .name = "peer_v4", .type = YNL_PT_U32, },
+	[FOU_ATTR_PEER_V6] = { .name = "peer_v6", .type = YNL_PT_BINARY,},
+	[FOU_ATTR_PEER_PORT] = { .name = "peer_port", .type = YNL_PT_U16, },
+	[FOU_ATTR_IFINDEX] = { .name = "ifindex", .type = YNL_PT_U32, },
+};
+
+struct ynl_policy_nest fou_nest = {
+	.max_attr = FOU_ATTR_MAX,
+	.table = fou_policy,
+};
+
+/* Common nested types */
+/* ============== FOU_CMD_ADD ============== */
+/* FOU_CMD_ADD - do */
+void fou_add_req_free(struct fou_add_req *req)
+{
+	free(req->local_v6);
+	free(req->peer_v6);
+	free(req);
+}
+
+int fou_add(struct ynl_sock *ys, struct fou_add_req *req)
+{
+	struct nlmsghdr *nlh;
+	int err;
+
+	nlh = ynl_gemsg_start_req(ys, ys->family_id, FOU_CMD_ADD, 1);
+	ys->req_policy = &fou_nest;
+
+	if (req->_present.port)
+		mnl_attr_put_u16(nlh, FOU_ATTR_PORT, req->port);
+	if (req->_present.ipproto)
+		mnl_attr_put_u8(nlh, FOU_ATTR_IPPROTO, req->ipproto);
+	if (req->_present.type)
+		mnl_attr_put_u8(nlh, FOU_ATTR_TYPE, req->type);
+	if (req->_present.remcsum_nopartial)
+		mnl_attr_put(nlh, FOU_ATTR_REMCSUM_NOPARTIAL, 0, NULL);
+	if (req->_present.local_v4)
+		mnl_attr_put_u32(nlh, FOU_ATTR_LOCAL_V4, req->local_v4);
+	if (req->_present.peer_v4)
+		mnl_attr_put_u32(nlh, FOU_ATTR_PEER_V4, req->peer_v4);
+	if (req->_present.local_v6_len)
+		mnl_attr_put(nlh, FOU_ATTR_LOCAL_V6, req->_present.local_v6_len, req->local_v6);
+	if (req->_present.peer_v6_len)
+		mnl_attr_put(nlh, FOU_ATTR_PEER_V6, req->_present.peer_v6_len, req->peer_v6);
+	if (req->_present.peer_port)
+		mnl_attr_put_u16(nlh, FOU_ATTR_PEER_PORT, req->peer_port);
+	if (req->_present.ifindex)
+		mnl_attr_put_u32(nlh, FOU_ATTR_IFINDEX, req->ifindex);
+
+	err = ynl_exec(ys, nlh, NULL);
+	if (err < 0)
+		return -1;
+
+	return 0;
+}
+
+/* ============== FOU_CMD_DEL ============== */
+/* FOU_CMD_DEL - do */
+void fou_del_req_free(struct fou_del_req *req)
+{
+	free(req->local_v6);
+	free(req->peer_v6);
+	free(req);
+}
+
+int fou_del(struct ynl_sock *ys, struct fou_del_req *req)
+{
+	struct nlmsghdr *nlh;
+	int err;
+
+	nlh = ynl_gemsg_start_req(ys, ys->family_id, FOU_CMD_DEL, 1);
+	ys->req_policy = &fou_nest;
+
+	if (req->_present.af)
+		mnl_attr_put_u8(nlh, FOU_ATTR_AF, req->af);
+	if (req->_present.ifindex)
+		mnl_attr_put_u32(nlh, FOU_ATTR_IFINDEX, req->ifindex);
+	if (req->_present.port)
+		mnl_attr_put_u16(nlh, FOU_ATTR_PORT, req->port);
+	if (req->_present.peer_port)
+		mnl_attr_put_u16(nlh, FOU_ATTR_PEER_PORT, req->peer_port);
+	if (req->_present.local_v4)
+		mnl_attr_put_u32(nlh, FOU_ATTR_LOCAL_V4, req->local_v4);
+	if (req->_present.peer_v4)
+		mnl_attr_put_u32(nlh, FOU_ATTR_PEER_V4, req->peer_v4);
+	if (req->_present.local_v6_len)
+		mnl_attr_put(nlh, FOU_ATTR_LOCAL_V6, req->_present.local_v6_len, req->local_v6);
+	if (req->_present.peer_v6_len)
+		mnl_attr_put(nlh, FOU_ATTR_PEER_V6, req->_present.peer_v6_len, req->peer_v6);
+
+	err = ynl_exec(ys, nlh, NULL);
+	if (err < 0)
+		return -1;
+
+	return 0;
+}
+
+/* ============== FOU_CMD_GET ============== */
+/* FOU_CMD_GET - do */
+void fou_get_req_free(struct fou_get_req *req)
+{
+	free(req->local_v6);
+	free(req->peer_v6);
+	free(req);
+}
+
+void fou_get_rsp_free(struct fou_get_rsp *rsp)
+{
+	free(rsp->local_v6);
+	free(rsp->peer_v6);
+	free(rsp);
+}
+
+int fou_get_rsp_parse(const struct nlmsghdr *nlh, void *data)
+{
+	struct ynl_parse_arg *yarg = data;
+	const struct nlattr *attr;
+	struct fou_get_rsp *dst;
+
+	dst = yarg->data;
+
+	mnl_attr_for_each(attr, nlh, sizeof(struct genlmsghdr)) {
+		if (mnl_attr_get_type(attr) == FOU_ATTR_PORT) {
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+			dst->_present.port = 1;
+			dst->port = mnl_attr_get_u16(attr);
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_IPPROTO) {
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+			dst->_present.ipproto = 1;
+			dst->ipproto = mnl_attr_get_u8(attr);
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_TYPE) {
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+			dst->_present.type = 1;
+			dst->type = mnl_attr_get_u8(attr);
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_REMCSUM_NOPARTIAL) {
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+			dst->_present.remcsum_nopartial = 1;
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_LOCAL_V4) {
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+			dst->_present.local_v4 = 1;
+			dst->local_v4 = mnl_attr_get_u32(attr);
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_PEER_V4) {
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+			dst->_present.peer_v4 = 1;
+			dst->peer_v4 = mnl_attr_get_u32(attr);
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_LOCAL_V6) {
+			unsigned int len;
+
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+
+			len = mnl_attr_get_payload_len(attr);
+			dst->_present.local_v6_len = len;
+			dst->local_v6 = malloc(len);
+			memcpy(dst->local_v6, mnl_attr_get_payload(attr), len);
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_PEER_V6) {
+			unsigned int len;
+
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+
+			len = mnl_attr_get_payload_len(attr);
+			dst->_present.peer_v6_len = len;
+			dst->peer_v6 = malloc(len);
+			memcpy(dst->peer_v6, mnl_attr_get_payload(attr), len);
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_PEER_PORT) {
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+			dst->_present.peer_port = 1;
+			dst->peer_port = mnl_attr_get_u16(attr);
+		}
+		else if (mnl_attr_get_type(attr) == FOU_ATTR_IFINDEX) {
+			if (ynl_attr_validate(yarg, attr))
+				return MNL_CB_ERROR;
+			dst->_present.ifindex = 1;
+			dst->ifindex = mnl_attr_get_u32(attr);
+		}
+	}
+
+	return MNL_CB_OK;
+}
+
+struct fou_get_rsp *fou_get(struct ynl_sock *ys, struct fou_get_req *req)
+{
+	struct ynl_req_state yrs = { .yarg = { .ys = ys, }, };
+	struct fou_get_rsp *rsp;
+	struct nlmsghdr *nlh;
+	int err;
+
+	nlh = ynl_gemsg_start_req(ys, ys->family_id, FOU_CMD_GET, 1);
+	ys->req_policy = &fou_nest;
+	yrs.yarg.rsp_policy = &fou_nest;
+
+	if (req->_present.af)
+		mnl_attr_put_u8(nlh, FOU_ATTR_AF, req->af);
+	if (req->_present.ifindex)
+		mnl_attr_put_u32(nlh, FOU_ATTR_IFINDEX, req->ifindex);
+	if (req->_present.port)
+		mnl_attr_put_u16(nlh, FOU_ATTR_PORT, req->port);
+	if (req->_present.peer_port)
+		mnl_attr_put_u16(nlh, FOU_ATTR_PEER_PORT, req->peer_port);
+	if (req->_present.local_v4)
+		mnl_attr_put_u32(nlh, FOU_ATTR_LOCAL_V4, req->local_v4);
+	if (req->_present.peer_v4)
+		mnl_attr_put_u32(nlh, FOU_ATTR_PEER_V4, req->peer_v4);
+	if (req->_present.local_v6_len)
+		mnl_attr_put(nlh, FOU_ATTR_LOCAL_V6, req->_present.local_v6_len, req->local_v6);
+	if (req->_present.peer_v6_len)
+		mnl_attr_put(nlh, FOU_ATTR_PEER_V6, req->_present.peer_v6_len, req->peer_v6);
+
+	rsp = calloc(1, sizeof(*rsp));
+	yrs.yarg.data = rsp;
+	yrs.cb = fou_get_rsp_parse;
+	yrs.rsp_cmd = FOU_CMD_GET;
+
+	err = ynl_exec(ys, nlh, &yrs);
+	if (err < 0)
+		goto err_free;
+
+	return rsp;
+
+err_free:
+	fou_get_rsp_free(rsp);
+	return NULL;
+}
+
+/* FOU_CMD_GET - dump */
+void fou_get_list_free(struct fou_get_list *rsp)
+{
+	struct fou_get_list *next = rsp;
+
+	while ((void *)next != YNL_LIST_END) {
+		rsp = next;
+		next = rsp->next;
+
+		free(rsp->obj.local_v6);
+		free(rsp->obj.peer_v6);
+		free(rsp);
+	}
+}
+
+struct fou_get_list *fou_get_dump(struct ynl_sock *ys)
+{
+	struct ynl_dump_state yds = {};
+	struct nlmsghdr *nlh;
+	int err;
+
+	yds.ys = ys;
+	yds.alloc_sz = sizeof(struct fou_get_list);
+	yds.cb = fou_get_rsp_parse;
+	yds.rsp_cmd = FOU_CMD_GET;
+	yds.rsp_policy = &fou_nest;
+
+	nlh = ynl_gemsg_start_dump(ys, ys->family_id, FOU_CMD_GET, 1);
+
+	err = ynl_exec_dump(ys, nlh, &yds);
+	if (err < 0)
+		goto free_list;
+
+	return yds.first;
+
+free_list:
+	fou_get_list_free(yds.first);
+	return NULL;
+}
+
+const struct ynl_family ynl_fou_family =  {
+	.name		= "fou",
+};