net/netlink/genetlink.c

55 static void genl_op_lock(const struct genl_family *family)
57 	if (!family->parallel_ops)
61 static void genl_op_unlock(const struct genl_family *family)
63 	if (!family->parallel_ops)
82  * also abused this API and relied on family == group ID, we
83  * cater to that by giving it a static family and group ID.
99 static int genl_ctrl_event(int event, const struct genl_family *family,
104 genl_op_fill_in_reject_policy(const struct genl_family *family,
109 	if (op->policy || op->cmd < family->resv_start_op)
117 genl_op_fill_in_reject_policy_split(const struct genl_family *family,
134 	const struct genl_family *family;
137 	idr_for_each_entry(&genl_fam_idr, family, id)
138 		if (strcmp(family->name, name) == 0)
139 			return family;
145 	const struct genl_family *family;
154 static void genl_op_from_full(const struct genl_family *family,
157 	*op = family->ops[i];
160 		op->maxattr = family->maxattr;
162 		op->policy = family->policy;
164 	genl_op_fill_in_reject_policy(family, op);
167 static int genl_get_cmd_full(u32 cmd, const struct genl_family *family,
172 	for (i = 0; i < family->n_ops; i++)
173 		if (family->ops[i].cmd == cmd) {
174 			genl_op_from_full(family, i, op);
181 static void genl_op_from_small(const struct genl_family *family,
185 	op->doit	= family->small_ops[i].doit;
186 	op->dumpit	= family->small_ops[i].dumpit;
187 	op->cmd		= family->small_ops[i].cmd;
188 	op->internal_flags = family->small_ops[i].internal_flags;
189 	op->flags	= family->small_ops[i].flags;
190 	op->validate	= family->small_ops[i].validate;
192 	op->maxattr = family->maxattr;
193 	op->policy = family->policy;
195 	genl_op_fill_in_reject_policy(family, op);
198 static int genl_get_cmd_small(u32 cmd, const struct genl_family *family,
203 	for (i = 0; i < family->n_small_ops; i++)
204 		if (family->small_ops[i].cmd == cmd) {
205 			genl_op_from_small(family, i, op);
214 	const struct genl_family *family = iter->family;
217 	i = iter->entry_idx - family->n_ops - family->n_small_ops;
219 	if (family->split_ops[i + cnt].flags & GENL_CMD_CAP_DO) {
220 		iter->doit = family->split_ops[i + cnt];
221 		genl_op_fill_in_reject_policy_split(family, &iter->doit);
227 	if (i + cnt < family->n_split_ops &&
228 	    family->split_ops[i + cnt].flags & GENL_CMD_CAP_DUMP &&
229 	    (!cnt || family->split_ops[i + cnt].cmd == iter->doit.cmd)) {
230 		iter->dumpit = family->split_ops[i + cnt];
231 		genl_op_fill_in_reject_policy_split(family, &iter->dumpit);
242 genl_get_cmd_split(u32 cmd, u8 flag, const struct genl_family *family,
247 	for (i = 0; i < family->n_split_ops; i++)
248 		if (family->split_ops[i].cmd == cmd &&
249 		    family->split_ops[i].flags & flag) {
250 			*op = family->split_ops[i];
259 		       const struct genl_family *family,
273 		op->pre_doit	= family->pre_doit;
275 		op->post_doit	= family->post_doit;
300 genl_get_cmd(u32 cmd, u8 flags, const struct genl_family *family,
306 	err = genl_get_cmd_full(cmd, family, &full);
308 		err = genl_get_cmd_small(cmd, family, &full);
311 		return genl_cmd_full_to_split(op, family, &full, flags);
313 	err = genl_get_cmd_split(cmd, flags, family, op);
323 genl_get_cmd_both(u32 cmd, const struct genl_family *family,
328 	err1 = genl_get_cmd(cmd, GENL_CMD_CAP_DO, family, doit);
329 	err2 = genl_get_cmd(cmd, GENL_CMD_CAP_DUMP, family, dumpit);
335 genl_op_iter_init(const struct genl_family *family, struct genl_op_iter *iter)
337 	iter->family = family;
343 	return iter->family->n_ops +
344 		iter->family->n_small_ops +
345 		iter->family->n_split_ops;
350 	const struct genl_family *family = iter->family;
354 	if (iter->entry_idx < family->n_ops) {
355 		genl_op_from_full(family, iter->entry_idx, &op);
356 	} else if (iter->entry_idx < family->n_ops + family->n_small_ops) {
357 		genl_op_from_small(family, iter->entry_idx - family->n_ops,
360 		   family->n_ops + family->n_small_ops + family->n_split_ops) {
373 		genl_cmd_full_to_split(&iter->doit, family,
375 		genl_cmd_full_to_split(&iter->dumpit, family,
458 static int genl_validate_assign_mc_groups(struct genl_family *family)
461 	int n_groups = family->n_mcgrps;
469 		const struct genl_multicast_group *grp = &family->mcgrps[i];
478 	if (family == &genl_ctrl) {
481 	} else if (strcmp(family->name, "NET_DM") == 0) {
484 	} else if (family->id == GENL_ID_VFS_DQUOT) {
487 	} else if (family->id == GENL_ID_PMCRAID) {
497 	family->mcgrp_offset = first_id;
503 	if (family->netnsok) {
529 		for (i = 0; i < family->n_mcgrps; i++)
530 			clear_bit(family->mcgrp_offset + i, mc_groups);
536 static void genl_unregister_mc_groups(const struct genl_family *family)
544 		for (i = 0; i < family->n_mcgrps; i++)
546 				net->genl_sock, family->mcgrp_offset + i);
551 	for (i = 0; i < family->n_mcgrps; i++) {
552 		int grp_id = family->mcgrp_offset + i;
556 		genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, family,
557 				&family->mcgrps[i], grp_id);
569 static int genl_validate_ops(const struct genl_family *family)
574 	if (WARN_ON(family->n_ops && !family->ops) ||
575 	    WARN_ON(family->n_small_ops && !family->small_ops) ||
576 	    WARN_ON(family->n_split_ops && !family->split_ops))
579 	for (genl_op_iter_init(family, &i); genl_op_iter_next(&i); ) {
583 		if (WARN_ON(i.cmd >= family->resv_start_op &&
594 	if (family->n_split_ops) {
595 		if (genl_split_op_check(&family->split_ops[0]))
599 	for (s = 1; s < family->n_split_ops; s++) {
602 		a = &family->split_ops[s - 1];
603 		b = &family->split_ops[s];
634 static void *genl_sk_priv_alloc(struct genl_family *family)
638 	priv = kzalloc(family->sock_priv_size, GFP_KERNEL);
642 	if (family->sock_priv_init)
643 		family->sock_priv_init(priv);
648 static void genl_sk_priv_free(const struct genl_family *family, void *priv)
650 	if (family->sock_priv_destroy)
651 		family->sock_priv_destroy(priv);
655 static int genl_sk_privs_alloc(struct genl_family *family)
657 	if (!family->sock_priv_size)
660 	family->sock_privs = kzalloc(sizeof(*family->sock_privs), GFP_KERNEL);
661 	if (!family->sock_privs)
663 	xa_init(family->sock_privs);
667 static void genl_sk_privs_free(const struct genl_family *family)
672 	if (!family->sock_priv_size)
675 	xa_for_each(family->sock_privs, id, priv)
676 		genl_sk_priv_free(family, priv);
678 	xa_destroy(family->sock_privs);
679 	kfree(family->sock_privs);
682 static void genl_sk_priv_free_by_sock(struct genl_family *family,
687 	if (!family->sock_priv_size)
689 	priv = xa_erase(family->sock_privs, (unsigned long) sk);
692 	genl_sk_priv_free(family, priv);
697 	struct genl_family *family;
702 	idr_for_each_entry(&genl_fam_idr, family, id)
703 		genl_sk_priv_free_by_sock(family, sk);
709  * __genl_sk_priv_get - Get family private pointer for socket, if exists
711  * @family: family
714  * Lookup a private memory for a Generic netlink family and specified socket.
721 void *__genl_sk_priv_get(struct genl_family *family, struct sock *sk)
723 	if (WARN_ON_ONCE(!family->sock_privs))
725 	return xa_load(family->sock_privs, (unsigned long) sk);
729  * genl_sk_priv_get - Get family private pointer for socket
731  * @family: family
734  * Lookup a private memory for a Generic netlink family and specified socket.
740 void *genl_sk_priv_get(struct genl_family *family, struct sock *sk)
744 	priv = __genl_sk_priv_get(family, sk);
748 	/* priv for the family does not exist so far, create it. */
750 	priv = genl_sk_priv_alloc(family);
754 	old_priv = xa_cmpxchg(family->sock_privs, (unsigned long) sk, NULL,
757 		genl_sk_priv_free(family, priv);
767  * genl_register_family - register a generic netlink family
768  * @family: generic netlink family
770  * Registers the specified family after validating it first. Only one
771  * family may be registered with the same family name or identifier.
773  * The family's ops, multicast groups and module pointer must already
778 int genl_register_family(struct genl_family *family)
783 	err = genl_validate_ops(family);
789 	if (genl_family_find_byname(family->name)) {
794 	err = genl_sk_privs_alloc(family);
801 	 * and having used their family ID also as their
805 	if (family == &genl_ctrl) {
806 		/* and this needs to be special for initial family lookups */
808 	} else if (strcmp(family->name, "pmcraid") == 0) {
810 	} else if (strcmp(family->name, "VFS_DQUOT") == 0) {
814 	family->id = idr_alloc_cyclic(&genl_fam_idr, family,
816 	if (family->id < 0) {
817 		err = family->id;
821 	err = genl_validate_assign_mc_groups(family);
828 	genl_ctrl_event(CTRL_CMD_NEWFAMILY, family, NULL, 0);
829 	for (i = 0; i < family->n_mcgrps; i++)
830 		genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, family,
831 				&family->mcgrps[i], family->mcgrp_offset + i);
836 	idr_remove(&genl_fam_idr, family->id);
838 	genl_sk_privs_free(family);
846  * genl_unregister_family - unregister generic netlink family
847  * @family: generic netlink family
849  * Unregisters the specified family.
853 int genl_unregister_family(const struct genl_family *family)
857 	if (!genl_family_find_byid(family->id)) {
862 	genl_unregister_mc_groups(family);
864 	idr_remove(&genl_fam_idr, family->id);
870 	genl_sk_privs_free(family);
874 	genl_ctrl_event(CTRL_CMD_DELFAMILY, family, NULL, 0);
885  * @family: generic netlink family
892 		  const struct genl_family *family, int flags, u8 cmd)
897 	nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN +
898 			family->hdrsize, flags);
904 	hdr->version = family->version;
922 genl_family_rcv_msg_attrs_parse(const struct genl_family *family,
958 	const struct genl_family *family;
978 	attrs = genl_family_rcv_msg_attrs_parse(ctx->family, ctx->nlh, ctx->extack,
990 	info->info.family	= ctx->family;
1002 		genl_op_lock(ctx->family);
1004 		genl_op_unlock(ctx->family);
1024 	genl_op_lock(info->family);
1026 	genl_op_unlock(info->family);
1040 		genl_op_lock(info->family);
1042 		genl_op_unlock(info->family);
1049 static int genl_family_rcv_msg_dumpit(const struct genl_family *family,
1058 		.module = family->module,
1067 	ctx.family = family;
1073 	genl_op_unlock(family);
1075 	genl_op_lock(family);
1080 static int genl_family_rcv_msg_doit(const struct genl_family *family,
1091 	attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack,
1099 	info.family = family;
1124 static int genl_header_check(const struct genl_family *family,
1131 	if (hdr->cmd < family->resv_start_op)
1154 static int genl_family_rcv_msg(const struct genl_family *family,
1165 	/* this family doesn't exist in this netns */
1166 	if (!family->netnsok && !net_eq(net, &init_net))
1169 	hdrlen = GENL_HDRLEN + family->hdrsize;
1173 	if (genl_header_check(family, nlh, hdr, extack))
1178 	if (genl_get_cmd(hdr->cmd, flags, family, &op))
1190 		return genl_family_rcv_msg_dumpit(family, skb, nlh, extack,
1193 		return genl_family_rcv_msg_doit(family, skb, nlh, extack,
1200 	const struct genl_family *family;
1203 	family = genl_family_find_byid(nlh->nlmsg_type);
1204 	if (family == NULL)
1207 	genl_op_lock(family);
1208 	err = genl_family_rcv_msg(family, skb, nlh, extack);
1209 	genl_op_unlock(family);
1227 static int ctrl_fill_info(const struct genl_family *family, u32 portid, u32 seq,
1237 	if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) ||
1238 	    nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) ||
1239 	    nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) ||
1240 	    nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) ||
1241 	    nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr))
1244 	if (genl_op_iter_init(family, &i)) {
1273 	if (family->n_mcgrps) {
1281 		for (i = 0; i < family->n_mcgrps; i++) {
1285 			grp = &family->mcgrps[i];
1292 					family->mcgrp_offset + i) ||
1310 static int ctrl_fill_mcgrp_info(const struct genl_family *family,
1323 	if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) ||
1324 	    nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id))
1380 static struct sk_buff *ctrl_build_family_msg(const struct genl_family *family,
1390 	err = ctrl_fill_info(family, portid, seq, 0, skb, cmd);
1400 ctrl_build_mcgrp_msg(const struct genl_family *family,
1411 	err = ctrl_fill_mcgrp_info(family, grp, grp_id, portid,
1448 			request_module("net-pf-%d-proto-%d-family-%s",
1462 		/* family doesn't exist here */
1474 static int genl_ctrl_event(int event, const struct genl_family *family,
1488 		msg = ctrl_build_family_msg(family, 0, 0, event);
1493 		msg = ctrl_build_mcgrp_msg(family, grp, grp_id, 0, 0, event);
1502 	if (!family->netnsok) {
1816 	const struct genl_family *family;
1822 	idr_for_each_entry(&genl_fam_idr, family, id) {
1826 		if (family->n_mcgrps == 0)
1829 		i = group - family->mcgrp_offset;
1830 		if (i < 0 || i >= family->n_mcgrps)
1833 		grp = &family->mcgrps[i];
1841 		if (family->bind)
1842 			family->bind(i);
1853 	const struct genl_family *family;
1858 	idr_for_each_entry(&genl_fam_idr, family, id) {
1861 		if (family->n_mcgrps == 0)
1864 		i = group - family->mcgrp_offset;
1865 		if (i < 0 || i >= family->n_mcgrps)
1868 		if (family->unbind)
1869 			family->unbind(i);
1967 int genlmsg_multicast_allns(const struct genl_family *family,
1971 	if (WARN_ON_ONCE(group >= family->n_mcgrps))
1974 	group = family->mcgrp_offset + group;
1979 void genl_notify(const struct genl_family *family, struct sk_buff *skb,
1985 	if (WARN_ON_ONCE(group >= family->n_mcgrps))
1988 	group = family->mcgrp_offset + group;