1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org> 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 #ifndef _NETLINK_NETLINK_SNL_GENERIC_H_ 28 #define _NETLINK_NETLINK_SNL_GENERIC_H_ 29 30 #include <netlink/netlink.h> 31 #include <netlink/netlink_generic.h> 32 #include <netlink/netlink_snl.h> 33 34 /* Genetlink helpers */ 35 static inline struct nlmsghdr * 36 snl_create_genl_msg_request(struct snl_writer *nw, int genl_family, uint8_t genl_cmd) 37 { 38 assert(nw->hdr == NULL); 39 40 struct nlmsghdr *hdr = snl_reserve_msg_object(nw, struct nlmsghdr); 41 hdr->nlmsg_type = genl_family; 42 hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; 43 nw->hdr = hdr; 44 struct genlmsghdr *ghdr = snl_reserve_msg_object(nw, struct genlmsghdr); 45 ghdr->cmd = genl_cmd; 46 47 return (hdr); 48 } 49 50 static struct snl_field_parser snl_fp_genl[] = {}; 51 52 #define SNL_DECLARE_GENL_PARSER(_name, _np) SNL_DECLARE_PARSER(_name,\ 53 struct genlmsghdr, snl_fp_genl, _np) 54 55 struct snl_genl_ctrl_mcast_group { 56 uint32_t mcast_grp_id; 57 char *mcast_grp_name; 58 }; 59 60 struct snl_genl_ctrl_mcast_groups { 61 uint32_t num_groups; 62 struct snl_genl_ctrl_mcast_group **groups; 63 }; 64 65 #define _OUT(_field) offsetof(struct snl_genl_ctrl_mcast_group, _field) 66 static struct snl_attr_parser _nla_p_getmc[] = { 67 { .type = CTRL_ATTR_MCAST_GRP_NAME, .off = _OUT(mcast_grp_name), .cb = snl_attr_get_string }, 68 { .type = CTRL_ATTR_MCAST_GRP_ID, .off = _OUT(mcast_grp_id), .cb = snl_attr_get_uint32 }, 69 }; 70 #undef _OUT 71 SNL_DECLARE_ATTR_PARSER_EXT(_genl_ctrl_mc_parser, 72 sizeof(struct snl_genl_ctrl_mcast_group), 73 _nla_p_getmc, NULL); 74 75 struct _getfamily_attrs { 76 uint16_t family_id; 77 char *family_name; 78 struct snl_genl_ctrl_mcast_groups mcast_groups; 79 }; 80 81 #define _IN(_field) offsetof(struct genlmsghdr, _field) 82 #define _OUT(_field) offsetof(struct _getfamily_attrs, _field) 83 static struct snl_attr_parser _nla_p_getfam[] = { 84 { .type = CTRL_ATTR_FAMILY_ID , .off = _OUT(family_id), .cb = snl_attr_get_uint16 }, 85 { .type = CTRL_ATTR_FAMILY_NAME, .off = _OUT(family_name), .cb = snl_attr_get_string }, 86 { 87 .type = CTRL_ATTR_MCAST_GROUPS, 88 .off = _OUT(mcast_groups), 89 .cb = snl_attr_get_parray, 90 .arg = &_genl_ctrl_mc_parser, 91 }, 92 }; 93 #undef _IN 94 #undef _OUT 95 SNL_DECLARE_GENL_PARSER(_genl_ctrl_getfam_parser, _nla_p_getfam); 96 97 static bool 98 snl_get_genl_family_info(struct snl_state *ss, const char *family_name, 99 struct _getfamily_attrs *attrs) 100 { 101 struct snl_writer nw; 102 struct nlmsghdr *hdr; 103 104 memset(attrs, 0, sizeof(*attrs)); 105 106 snl_init_writer(ss, &nw); 107 hdr = snl_create_genl_msg_request(&nw, GENL_ID_CTRL, CTRL_CMD_GETFAMILY); 108 snl_add_msg_attr_string(&nw, CTRL_ATTR_FAMILY_NAME, family_name); 109 if ((hdr = snl_finalize_msg(&nw)) == NULL || !snl_send_message(ss, hdr)) 110 return (false); 111 112 hdr = snl_read_reply(ss, hdr->nlmsg_seq); 113 if (hdr != NULL && hdr->nlmsg_type != NLMSG_ERROR) { 114 if (snl_parse_nlmsg(ss, hdr, &_genl_ctrl_getfam_parser, attrs)) 115 return (true); 116 } 117 118 return (false); 119 } 120 121 static inline uint16_t 122 snl_get_genl_family(struct snl_state *ss, const char *family_name) 123 { 124 struct _getfamily_attrs attrs = {}; 125 126 snl_get_genl_family_info(ss, family_name, &attrs); 127 return (attrs.family_id); 128 } 129 130 static const struct snl_hdr_parser *snl_all_genl_parsers[] = { 131 &_genl_ctrl_getfam_parser, &_genl_ctrl_mc_parser, 132 }; 133 134 #endif 135