Differential D36002 Diff 110147 sys/netlink/netlink_message_parser.h

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sys/netlink/netlink_message_parser.h

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				/*-
				* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
				*
				* Copyright (c) 2022 Alexander V. Chernikov
				*
				* Redistribution and use in source and binary forms, with or without
				* modification, are permitted provided that the following conditions
				* are met:
				* 1. Redistributions of source code must retain the above copyright
				* notice, this list of conditions and the following disclaimer.
				* 2. Redistributions in binary form must reproduce the above copyright
				* notice, this list of conditions and the following disclaimer in the
				* documentation and/or other materials provided with the distribution.
				*
				* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
				* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
				* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
				* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
				* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
				* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
				* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
				* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
				* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
				* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
				* SUCH DAMAGE.
				*/

				#ifndef _NETLINK_NETLINK_MESSAGE_PARSER_H_
				#define _NETLINK_NETLINK_MESSAGE_PARSER_H_

				/*
				* It is not meant to be included directly
				*/

				struct netlink_parse_tracker;
				typedef int parse_field_f(void hdr, struct netlink_parse_tracker npt,
				void *target);
				struct nlfield_parser {
				uint16_t off_in;
				uint16_t off_out;
				parse_field_f *cb;
				};

				int nlf_get_ifp(void src, struct netlink_parse_tracker npt, void *target);
				int nlf_get_ifpz(void src, struct netlink_parse_tracker npt, void *target);
				int nlf_get_u8(void src, struct netlink_parse_tracker npt, void *target);


				typedef int parse_attr_f(struct nlattr attr, struct netlink_parse_tracker npt,
				void *target);
				struct nlattr_parser {
				uint16_t type; /* Attribute type */
				uint16_t off; /* field offset in the target structure */
				parse_attr_f cb; / parser function to call */
				};

				struct nlhdr_parser {
				int hdr_off; /* aligned header size */
				int fp_size;
				int np_size;
				struct nlfield_parser fp; / array of header field parsers */
				struct nlattr_parser np; / array of attribute parsers */
				};

				int nl_parse_attrs_raw(struct nlattr nla_head, int len, struct nlattr_parser ps,
				int pslen, struct netlink_parse_tracker npt, void target);
				int nl_parse_attrs(struct nlmsghdr hdr, int hdrlen, struct nlattr_parser ps,
				int pslen, struct netlink_parse_tracker npt, void target);
				int nl_parse_header(void hdr, int len, struct nlhdr_parser parser,
				struct netlink_parse_tracker npt, void target);
				int nl_parse_nlmsg(struct nlmsghdr hdr, struct nlhdr_parser parser,
				struct netlink_parse_tracker npt, void target);

				int nlattr_get_flag(struct nlattr nla, struct netlink_parse_tracker npt,
				void *target);
				int nlattr_get_ip(struct nlattr nla, struct netlink_parse_tracker npt,
				void *target);
				int nlattr_get_uint32(struct nlattr nla, struct netlink_parse_tracker npt,
				void *target);
				int nlattr_get_ifp(struct nlattr nla, struct netlink_parse_tracker npt,
				void *target);
				int nlattr_get_ifpz(struct nlattr nla, struct netlink_parse_tracker npt,
				void *target);
				int nlattr_get_ipvia(struct nlattr nla, struct netlink_parse_tracker npt,
				void *target);
				int nlattr_get_string(struct nlattr nla, struct netlink_parse_tracker npt,
				void *target);
				int nlattr_get_nla(struct nlattr nla, struct netlink_parse_tracker npt,
				void *target);

				/* Parsing state */
				struct linear_buffer {
				char base; / Base allocated memory pointer */
				uint32_t offset; /* Currently used offset */
				uint32_t size; /* Total buffer size */
				};

				static inline void *
				lb_alloc(struct linear_buffer *lb, int len)
				{
				len = roundup2(len, sizeof(uint64_t));
				if (lb->offset + len > lb->size)
				return (NULL);
				void data = (void )(lb->base + lb->offset);
				lb->offset += len;
				return (data);
				}

				static inline void
				lb_clear(struct linear_buffer *lb)
				{
				memset(lb->base, 0, lb->size);
				lb->offset = 0;
				}

				#define NL_MAX_ERROR_BUF 128
				#define SCRATCH_BUFFER_SIZE (1024 + NL_MAX_ERROR_BUF)
				struct netlink_parse_tracker {
				struct linear_buffer lb; /* Per-message scratch buffer */
				struct nlpcb nlp; / Originator socket */
				struct nlmsg_state ns; / Message writer to use */
				struct nlmsghdr hdr; / Current parsed message header */
				uint32_t err_off; /* error offset from hdr start */
				int error; /* last operation error */
				char err_msg; / Description of last error */
				};

				static inline void *
				npt_alloc(struct netlink_parse_tracker *npt, int len)
				{
				return (lb_alloc(&npt->lb, len));
				}
				#define npt_alloc_sockaddr(_npt, _len) ((struct sockaddr *)(npt_alloc(_npt, _len)))

				bool nlmsg_report_err_msg(struct netlink_parse_tracker npt, const char fmt, ...);

				#define NLMSG_REPORT_ERR_MSG(_npt, _fmt, ...) { \
				nlmsg_report_err_msg(_npt, _fmt, ## __VA_ARGS__); \
				NLP_LOG(LOG_DEBUG, (_npt)->nlp, _fmt, ## __VA_ARGS__); \
				}

				bool nlmsg_report_err_offset(struct netlink_parse_tracker *npt, uint32_t off);

				#endif