1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2023 Baptiste Daroussin <bapt@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 28 #include <sys/param.h> 29 #include <sys/types.h> 30 #include <sys/devctl.h> 31 #include <sys/errno.h> 32 #include <sys/module.h> 33 #include <sys/kernel.h> 34 #include <sys/malloc.h> 35 #include <net/vnet.h> 36 #include <netlink/netlink.h> 37 #include <netlink/netlink_ctl.h> 38 #include <netlink/netlink_generic.h> 39 #include <netlink/netlink_sysevent.h> 40 41 #define DEBUG_MOD_NAME nl_sysevent 42 #define DEBUG_MAX_LEVEL LOG_DEBUG3 43 #include <netlink/netlink_debug.h> 44 _DECLARE_DEBUG(LOG_INFO); 45 46 MALLOC_DEFINE(M_NLSE, "nlsysevent", "Memory used for Netlink sysevent"); 47 #define NLSE_FAMILY_NAME "nlsysevent" 48 static uint32_t ctrl_family_id; 49 50 #define MAX_SYSEVENT_GROUPS 64 51 static struct sysevent_group { 52 char *name; 53 uint32_t id; 54 } sysevent_groups[MAX_SYSEVENT_GROUPS] = {}; 55 56 static const char *devctl_systems[] = { 57 "ACPI", 58 "AEON", 59 "CAM", 60 "CARP", 61 "coretemp", 62 "DEVFS", 63 "device", 64 "ETHERNET", 65 "GEOM", 66 "HYPERV_NIC_VF", 67 "IFNET", 68 "INFINIBAND", 69 "KERNEL", 70 "nvme", 71 "PMU", 72 "RCTL", 73 "USB", 74 "VFS", 75 "VT", 76 "ZFS", 77 }; 78 79 static void 80 sysevent_write(struct sysevent_group *se, const char *subsystem, const char *type, 81 const char *data) 82 { 83 struct nl_writer nw; 84 85 if (!nl_writer_group(&nw, NLMSG_LARGE, NETLINK_GENERIC, se->id, 86 false)) { 87 NL_LOG(LOG_DEBUG, "error allocating group writer"); 88 return; 89 } 90 struct nlmsghdr hdr = { .nlmsg_type = ctrl_family_id }; 91 if (!nlmsg_reply(&nw, &hdr, sizeof(struct genlmsghdr))) { 92 return; 93 } 94 95 struct genlmsghdr *ghdr = nlmsg_reserve_object(&nw, struct genlmsghdr); 96 if (ghdr == NULL) { 97 NL_LOG(LOG_DEBUG, "unable to allocate memory"); 98 return; 99 } 100 ghdr->version = 0; 101 ghdr->cmd = NLSE_CMD_NEWEVENT; 102 ghdr->reserved = 0; 103 nlattr_add_string(&nw, NLSE_ATTR_SYSTEM, se->name); 104 nlattr_add_string(&nw, NLSE_ATTR_SUBSYSTEM, subsystem); 105 nlattr_add_string(&nw, NLSE_ATTR_TYPE, type); 106 if (data != NULL) 107 nlattr_add_string(&nw, NLSE_ATTR_DATA, data); 108 nlmsg_end(&nw); 109 nlmsg_flush(&nw); 110 } 111 112 static void 113 sysevent_new_group(size_t index, const char *name) 114 { 115 if (index >= MAX_SYSEVENT_GROUPS) { 116 NL_LOG(LOG_WARNING, "impossible to add the event %s, " 117 "too many event groups\n", name); 118 return; 119 } 120 sysevent_groups[index].name = strdup(name, M_NLSE); 121 sysevent_groups[index].id = genl_register_group(NLSE_FAMILY_NAME, sysevent_groups[index].name); 122 } 123 124 static struct sysevent_group * 125 sysevent_get_group(const char *system) 126 { 127 for (size_t i = 0; i < MAX_SYSEVENT_GROUPS; i++) { 128 if (sysevent_groups[i].name == NULL) { 129 sysevent_new_group(i, system); 130 return (&sysevent_groups[i]); 131 } 132 if (strcmp(sysevent_groups[i].name, system) == 0) 133 return (&sysevent_groups[i]); 134 } 135 136 return (NULL); 137 } 138 139 static void 140 sysevent_send(const char *system, const char *subsystem, const char *type, 141 const char *data) 142 { 143 struct sysevent_group *se = sysevent_get_group(system); 144 145 if (se == NULL) { 146 NL_LOG(LOG_WARNING, "impossible to add the event %s, " 147 "too many event groups\n", system); 148 return; 149 } 150 151 CURVNET_SET(vnet0); 152 sysevent_write(se, subsystem, type, data); 153 CURVNET_RESTORE(); 154 } 155 156 static void 157 nlsysevent_load(void) 158 { 159 devctl_set_notify_hook(sysevent_send); 160 ctrl_family_id = genl_register_family(NLSE_FAMILY_NAME, 0, 2, NLSE_ATTR_MAX); 161 for (size_t i = 0; i < nitems(devctl_systems); i++) { 162 if (i >= MAX_SYSEVENT_GROUPS) { 163 NL_LOG(LOG_WARNING, "impossible to add the event %s, too many events\n", devctl_systems[i]); 164 continue; 165 } 166 sysevent_new_group(i, devctl_systems[i]); 167 } 168 } 169 170 static void 171 nlsysevent_unload(void) 172 { 173 devctl_unset_notify_hook(); 174 genl_unregister_family(NLSE_FAMILY_NAME); 175 for (size_t i = 0; i < MAX_SYSEVENT_GROUPS; i++) { 176 if (sysevent_groups[i].name == NULL) 177 break; 178 free(sysevent_groups[i].name, M_NLSE); 179 } 180 } 181 182 static int 183 nlsysevent_loader(module_t mod __unused, int what, void *priv __unused) 184 { 185 int err = 0; 186 187 switch (what) { 188 case MOD_LOAD: 189 nlsysevent_load(); 190 break; 191 case MOD_UNLOAD: 192 nlsysevent_unload(); 193 break; 194 default: 195 err = EOPNOTSUPP; 196 break; 197 } 198 return (err); 199 } 200 static moduledata_t nlsysevent_mod = { "nlsysevent", nlsysevent_loader, NULL}; 201 202 DECLARE_MODULE(nlsysevent, nlsysevent_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); 203 MODULE_DEPEND(nlsysevent, netlink, 1, 1, 1); 204 MODULE_VERSION(nlsysevent, 1); 205