1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
  2#ifndef __YNL_C_H
  3#define __YNL_C_H 1
  4
  5#include <stddef.h>
  6#include <linux/genetlink.h>
  7#include <linux/types.h>
  8
  9#include "ynl-priv.h"
 10
 11enum ynl_error_code {
 12	YNL_ERROR_NONE = 0,
 13	__YNL_ERRNO_END = 4096,
 14	YNL_ERROR_INTERNAL,
 15	YNL_ERROR_EXPECT_ACK,
 16	YNL_ERROR_EXPECT_MSG,
 17	YNL_ERROR_UNEXPECT_MSG,
 18	YNL_ERROR_ATTR_MISSING,
 19	YNL_ERROR_ATTR_INVALID,
 20	YNL_ERROR_UNKNOWN_NTF,
 21	YNL_ERROR_INV_RESP,
 22};
 23
 24/**
 25 * struct ynl_error - error encountered by YNL
 26 * @code:	errno (low values) or YNL error code (enum ynl_error_code)
 27 * @attr_offs:	offset of bad attribute (for very advanced users)
 28 * @msg:	error message
 29 *
 30 * Error information for when YNL operations fail.
 31 * Users should interact with the err member of struct ynl_sock directly.
 32 * The main exception to that rule is ynl_sock_create().
 33 */
 34struct ynl_error {
 35	enum ynl_error_code code;
 36	unsigned int attr_offs;
 37	char msg[512];
 38};
 39
 40/**
 41 * struct ynl_family - YNL family info
 42 * Family description generated by codegen. Pass to ynl_sock_create().
 43 */
 44struct ynl_family {
 45/* private: */
 46	const char *name;
 47	size_t hdr_len;
 48	const struct ynl_ntf_info *ntf_info;
 49	unsigned int ntf_info_size;
 50};
 51
 52/**
 53 * struct ynl_sock - YNL wrapped netlink socket
 54 * @err: YNL error descriptor, cleared on every request.
 55 */
 56struct ynl_sock {
 57	struct ynl_error err;
 58
 59/* private: */
 60	const struct ynl_family *family;
 61	struct mnl_socket *sock;
 62	__u32 seq;
 63	__u32 portid;
 64	__u16 family_id;
 65
 66	unsigned int n_mcast_groups;
 67	struct {
 68		unsigned int id;
 69		char name[GENL_NAMSIZ];
 70	} *mcast_groups;
 71
 72	struct ynl_ntf_base_type *ntf_first;
 73	struct ynl_ntf_base_type **ntf_last_next;
 74
 75	struct nlmsghdr *nlh;
 76	struct ynl_policy_nest *req_policy;
 77	unsigned char *tx_buf;
 78	unsigned char *rx_buf;
 79	unsigned char raw_buf[];
 80};
 81
 82struct ynl_sock *
 83ynl_sock_create(const struct ynl_family *yf, struct ynl_error *e);
 84void ynl_sock_destroy(struct ynl_sock *ys);
 85
 86#define ynl_dump_foreach(dump, iter)					\
 87	for (typeof(dump->obj) *iter = &dump->obj;			\
 88	     !ynl_dump_obj_is_last(iter);				\
 89	     iter = ynl_dump_obj_next(iter))
 90
 91int ynl_subscribe(struct ynl_sock *ys, const char *grp_name);
 92int ynl_socket_get_fd(struct ynl_sock *ys);
 93int ynl_ntf_check(struct ynl_sock *ys);
 94
 95/**
 96 * ynl_has_ntf() - check if socket has *parsed* notifications
 97 * @ys: active YNL socket
 98 *
 99 * Note that this does not take into account notifications sitting
100 * in netlink socket, just the notifications which have already been
101 * read and parsed (e.g. during a ynl_ntf_check() call).
102 */
103static inline bool ynl_has_ntf(struct ynl_sock *ys)
104{
105	return ys->ntf_last_next != &ys->ntf_first;
106}
107struct ynl_ntf_base_type *ynl_ntf_dequeue(struct ynl_sock *ys);
108
109void ynl_ntf_free(struct ynl_ntf_base_type *ntf);
110#endif