diff options
Diffstat (limited to 'sys/netlink/netlink_snl_generic.h')
| -rw-r--r-- | sys/netlink/netlink_snl_generic.h | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/sys/netlink/netlink_snl_generic.h b/sys/netlink/netlink_snl_generic.h new file mode 100644 index 000000000000..10e98a0266e0 --- /dev/null +++ b/sys/netlink/netlink_snl_generic.h @@ -0,0 +1,175 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org> + * + * 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_SNL_GENERIC_H_ +#define _NETLINK_NETLINK_SNL_GENERIC_H_ + +#include <netlink/netlink.h> +#include <netlink/netlink_generic.h> +#include <netlink/netlink_snl.h> + +/* Genetlink helpers */ +static inline struct nlmsghdr * +snl_create_genl_msg_request(struct snl_writer *nw, uint16_t genl_family, + uint8_t genl_cmd) +{ + struct nlmsghdr *hdr; + struct genlmsghdr *ghdr; + + assert(nw->hdr == NULL); + + hdr = snl_reserve_msg_object(nw, struct nlmsghdr); + if (__predict_false(hdr == NULL)) + return (NULL); + hdr->nlmsg_type = genl_family; + hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK; + ghdr = snl_reserve_msg_object(nw, struct genlmsghdr); + if (__predict_false(ghdr == NULL)) + return (NULL); + ghdr->cmd = genl_cmd; + nw->hdr = hdr; + + return (hdr); +} + +static struct snl_field_parser snl_fp_genl[] = {}; + +#define SNL_DECLARE_GENL_PARSER(_name, _np) SNL_DECLARE_PARSER(_name,\ + struct genlmsghdr, snl_fp_genl, _np) + +struct _snl_genl_ctrl_mcast_group { + uint32_t mcast_grp_id; + const char *mcast_grp_name; +}; + +struct _snl_genl_ctrl_mcast_groups { + uint32_t num_groups; + struct _snl_genl_ctrl_mcast_group **groups; +}; + +#define _OUT(_field) offsetof(struct _snl_genl_ctrl_mcast_group, _field) +static struct snl_attr_parser _nla_p_getmc[] = { + { + .type = CTRL_ATTR_MCAST_GRP_NAME, + .off = _OUT(mcast_grp_name), + .cb = snl_attr_get_string, + }, + { + .type = CTRL_ATTR_MCAST_GRP_ID, + .off = _OUT(mcast_grp_id), + .cb = snl_attr_get_uint32, + }, +}; +#undef _OUT +SNL_DECLARE_ATTR_PARSER_EXT(_genl_ctrl_mc_parser, + sizeof(struct _snl_genl_ctrl_mcast_group), _nla_p_getmc, NULL); + +struct _getfamily_attrs { + uint16_t family_id; + const char *family_name; + struct _snl_genl_ctrl_mcast_groups mcast_groups; +}; + +#define _IN(_field) offsetof(struct genlmsghdr, _field) +#define _OUT(_field) offsetof(struct _getfamily_attrs, _field) +static struct snl_attr_parser _nla_p_getfam[] = { + { + .type = CTRL_ATTR_FAMILY_ID, + .off = _OUT(family_id), + .cb = snl_attr_get_uint16, + }, + { + .type = CTRL_ATTR_FAMILY_NAME, + .off = _OUT(family_name), + .cb = snl_attr_get_string, + }, + { + .type = CTRL_ATTR_MCAST_GROUPS, + .off = _OUT(mcast_groups), + .cb = snl_attr_get_parray, + .arg = &_genl_ctrl_mc_parser, + }, +}; +#undef _IN +#undef _OUT +SNL_DECLARE_GENL_PARSER(_genl_ctrl_getfam_parser, _nla_p_getfam); + +static bool +_snl_get_genl_family_info(struct snl_state *ss, const char *family_name, + struct _getfamily_attrs *attrs) +{ + struct snl_writer nw; + struct nlmsghdr *hdr; + + memset(attrs, 0, sizeof(*attrs)); + + snl_init_writer(ss, &nw); + snl_create_genl_msg_request(&nw, GENL_ID_CTRL, CTRL_CMD_GETFAMILY); + snl_add_msg_attr_string(&nw, CTRL_ATTR_FAMILY_NAME, family_name); + if ((hdr = snl_finalize_msg(&nw)) == NULL || !snl_send_message(ss, hdr)) + return (false); + + hdr = snl_read_reply(ss, hdr->nlmsg_seq); + if (hdr != NULL && hdr->nlmsg_type != NLMSG_ERROR) { + if (snl_parse_nlmsg(ss, hdr, &_genl_ctrl_getfam_parser, attrs)) + return (true); + } + + return (false); +} + +static inline uint16_t +snl_get_genl_family(struct snl_state *ss, const char *family_name) +{ + struct _getfamily_attrs attrs = {}; + + if (__predict_false(!_snl_get_genl_family_info(ss, family_name, + &attrs))) + return (0); + return (attrs.family_id); +} + +static inline uint16_t +snl_get_genl_mcast_group(struct snl_state *ss, const char *family_name, + const char *group_name, uint16_t *family_id) +{ + struct _getfamily_attrs attrs = {}; + + if (__predict_false(!_snl_get_genl_family_info(ss, family_name, + &attrs))) + return (0); + if (attrs.family_id == 0) + return (0); + if (family_id != NULL) + *family_id = attrs.family_id; + for (u_int i = 0; i < attrs.mcast_groups.num_groups; i++) + if (strcmp(attrs.mcast_groups.groups[i]->mcast_grp_name, + group_name) == 0) + return (attrs.mcast_groups.groups[i]->mcast_grp_id); + return (0); +} + +#endif |