diff --git a/sys/netlink/netlink_message_parser.h b/sys/netlink/netlink_message_parser.h index 2f802b0961ad..b23b223ef80e 100644 --- a/sys/netlink/netlink_message_parser.h +++ b/sys/netlink/netlink_message_parser.h @@ -1,272 +1,274 @@ /*- * 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_ #ifdef _KERNEL /* * It is not meant to be included directly */ /* 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 nl_pstate { struct linear_buffer lb; /* Per-message scratch buffer */ struct nlpcb *nlp; /* Originator socket */ struct nl_writer *nw; /* 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 */ bool strict; /* Strict parsing required */ }; static inline void * npt_alloc(struct nl_pstate *npt, int len) { return (lb_alloc(&npt->lb, len)); } #define npt_alloc_sockaddr(_npt, _len) ((struct sockaddr *)(npt_alloc(_npt, _len))) typedef int parse_field_f(void *hdr, struct nl_pstate *npt, void *target); struct nlfield_parser { uint16_t off_in; uint16_t off_out; parse_field_f *cb; }; static const struct nlfield_parser nlf_p_empty[] = {}; int nlf_get_ifp(void *src, struct nl_pstate *npt, void *target); int nlf_get_ifpz(void *src, struct nl_pstate *npt, void *target); int nlf_get_u8(void *src, struct nl_pstate *npt, void *target); int nlf_get_u16(void *src, struct nl_pstate *npt, void *target); int nlf_get_u32(void *src, struct nl_pstate *npt, void *target); int nlf_get_u8_u32(void *src, struct nl_pstate *npt, void *target); struct nlattr_parser; typedef int parse_attr_f(struct nlattr *attr, struct nl_pstate *npt, const void *arg, 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 */ const void *arg; }; typedef bool strict_parser_f(void *hdr, struct nl_pstate *npt); struct nlhdr_parser { int nl_hdr_off; /* aligned netlink header size */ int out_hdr_off; /* target header size */ int fp_size; int np_size; const struct nlfield_parser *fp; /* array of header field parsers */ const struct nlattr_parser *np; /* array of attribute parsers */ strict_parser_f *sp; /* Parser function */ }; #define NL_DECLARE_PARSER(_name, _t, _fp, _np) \ static const struct nlhdr_parser _name = { \ .nl_hdr_off = sizeof(_t), \ .fp = &((_fp)[0]), \ .np = &((_np)[0]), \ .fp_size = NL_ARRAY_LEN(_fp), \ .np_size = NL_ARRAY_LEN(_np), \ } #define NL_DECLARE_STRICT_PARSER(_name, _t, _sp, _fp, _np)\ static const struct nlhdr_parser _name = { \ .nl_hdr_off = sizeof(_t), \ .fp = &((_fp)[0]), \ .np = &((_np)[0]), \ .fp_size = NL_ARRAY_LEN(_fp), \ .np_size = NL_ARRAY_LEN(_np), \ .sp = _sp, \ } #define NL_DECLARE_ARR_PARSER(_name, _t, _o, _fp, _np) \ static const struct nlhdr_parser _name = { \ .nl_hdr_off = sizeof(_t), \ .out_hdr_off = sizeof(_o), \ .fp = &((_fp)[0]), \ .np = &((_np)[0]), \ .fp_size = NL_ARRAY_LEN(_fp), \ .np_size = NL_ARRAY_LEN(_np), \ } #define NL_DECLARE_ATTR_PARSER(_name, _np) \ static const struct nlhdr_parser _name = { \ .np = &((_np)[0]), \ .np_size = NL_ARRAY_LEN(_np), \ } struct nlarr_hdr { int num_items; int max_items; }; int nl_parse_attrs_raw(struct nlattr *nla_head, int len, const struct nlattr_parser *ps, int pslen, struct nl_pstate *npt, void *target); int nl_parse_attrs(struct nlmsghdr *hdr, int hdrlen, struct nlattr_parser *ps, int pslen, struct nl_pstate *npt, void *target); int nlattr_get_flag(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_ip(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_uint16(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_uint32(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_uint64(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_ifp(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_ifpz(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_ipvia(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_string(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_stringn(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_nla(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); int nlattr_get_nested(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target); bool nlmsg_report_err_msg(struct nl_pstate *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 nl_pstate *npt, uint32_t off); /* * Have it inline so compiler can optimize field accesses into * the list of direct function calls without iteration. */ static inline int nl_parse_header(void *hdr, int len, const struct nlhdr_parser *parser, struct nl_pstate *npt, void *target) { int error; if (__predict_false(len < parser->nl_hdr_off)) { nlmsg_report_err_msg(npt, "header too short: expected %d, got %d", parser->nl_hdr_off, len); return (EINVAL); } if (npt->strict && parser->sp != NULL && !parser->sp(hdr, npt)) return (EINVAL); /* Extract fields first */ for (int i = 0; i < parser->fp_size; i++) { const struct nlfield_parser *fp = &parser->fp[i]; void *src = (char *)hdr + fp->off_in; void *dst = (char *)target + fp->off_out; error = fp->cb(src, npt, dst); if (error != 0) return (error); } struct nlattr *nla_head = (struct nlattr *)((char *)hdr + parser->nl_hdr_off); error = nl_parse_attrs_raw(nla_head, len - parser->nl_hdr_off, parser->np, parser->np_size, npt, target); return (error); } static inline int nl_parse_nested(struct nlattr *nla, const struct nlhdr_parser *parser, struct nl_pstate *npt, void *target) { struct nlattr *nla_head = (struct nlattr *)NLA_DATA(nla); return (nl_parse_attrs_raw(nla_head, NLA_DATA_LEN(nla), parser->np, parser->np_size, npt, target)); } /* * Checks that attributes are sorted by attribute type. */ static inline void nl_verify_parsers(const struct nlhdr_parser **parser, int count) { +#ifdef INVARIANTS for (int i = 0; i < count; i++) { const struct nlhdr_parser *p = parser[i]; int attr_type = 0; for (int j = 0; j < p->np_size; j++) { MPASS(p->np[j].type > attr_type); attr_type = p->np[j].type; } } +#endif } void nl_verify_parsers(const struct nlhdr_parser **parser, int count); #define NL_VERIFY_PARSERS(_p) nl_verify_parsers((_p), NL_ARRAY_LEN(_p)) static inline int nl_parse_nlmsg(struct nlmsghdr *hdr, const struct nlhdr_parser *parser, struct nl_pstate *npt, void *target) { return (nl_parse_header(hdr + 1, hdr->nlmsg_len - sizeof(*hdr), parser, npt, target)); } #endif #endif