xref: /freebsd/sys/netlink/netlink_var.h (revision 090e9752d7291db0c251a5576892e3bbbaea2479)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2021 Ng Peng Nam Sean
5  * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 #ifndef _NETLINK_NETLINK_VAR_H_
29 #define _NETLINK_NETLINK_VAR_H_
30 
31 #ifdef _KERNEL
32 
33 #include <sys/ck.h>
34 #include <sys/epoch.h>
35 #include <sys/sysctl.h>
36 #include <sys/taskqueue.h>
37 #include <net/vnet.h>
38 
39 #define	NLSNDQ  65536 /* Default socket sendspace */
40 #define	NLRCVQ	65536 /* Default socket recvspace */
41 
42 struct ucred;
43 
44 struct nl_io_queue {
45 	STAILQ_HEAD(, mbuf)	head;
46 	int			length;
47 	int			hiwat;
48 };
49 
50 #define	NLP_MAX_GROUPS		128
51 
52 struct nlpcb {
53         struct socket           *nl_socket;
54 	uint64_t	        nl_groups[NLP_MAX_GROUPS / 64];
55 	uint32_t                nl_port;
56 	uint32_t	        nl_flags;
57 	uint32_t	        nl_process_id;
58         int                     nl_proto;
59         bool			nl_active;
60 	bool			nl_bound;
61         bool			nl_task_pending;
62 	bool			nl_tx_blocked; /* No new requests accepted */
63 	bool			nl_linux; /* true if running under compat */
64 	bool			nl_unconstrained_vnet; /* true if running under VNET jail (or without jail) */
65 	struct nl_io_queue	rx_queue;
66 	struct nl_io_queue	tx_queue;
67 	struct taskqueue	*nl_taskqueue;
68 	struct task		nl_task;
69 	struct ucred		*nl_cred; /* Copy of nl_socket->so_cred */
70 	uint64_t		nl_dropped_bytes;
71 	uint64_t		nl_dropped_messages;
72         CK_LIST_ENTRY(nlpcb)    nl_next;
73         CK_LIST_ENTRY(nlpcb)    nl_port_next;
74 	volatile u_int		nl_refcount;
75 	struct mtx		nl_lock;
76 	struct epoch_context	nl_epoch_ctx;
77 };
78 #define sotonlpcb(so)       ((struct nlpcb *)(so)->so_pcb)
79 
80 #define	NLP_LOCK_INIT(_nlp)	mtx_init(&((_nlp)->nl_lock), "nlp mtx", NULL, MTX_DEF)
81 #define	NLP_LOCK_DESTROY(_nlp)	mtx_destroy(&((_nlp)->nl_lock))
82 #define	NLP_LOCK(_nlp)		mtx_lock(&((_nlp)->nl_lock))
83 #define	NLP_UNLOCK(_nlp)	mtx_unlock(&((_nlp)->nl_lock))
84 
85 #define	ALIGNED_NL_SZ(_data)	roundup2((((struct nlmsghdr *)(_data))->nlmsg_len), 16)
86 
87 /* nl_flags */
88 #define NLF_CAP_ACK             0x01 /* Do not send message body with errmsg */
89 #define NLF_EXT_ACK             0x02 /* Allow including extended TLVs in ack */
90 #define	NLF_STRICT		0x04 /* Perform strict header checks */
91 
92 SYSCTL_DECL(_net_netlink);
93 SYSCTL_DECL(_net_netlink_debug);
94 
95 struct nl_io {
96 	struct callout				callout;
97 	struct mbuf				*head;
98 	struct mbuf 				*last;
99 	int64_t					length;
100 };
101 
102 struct nl_control {
103 	CK_LIST_HEAD(nl_pid_head, nlpcb)	ctl_port_head;
104 	CK_LIST_HEAD(nlpcb_head, nlpcb)		ctl_pcb_head;
105 	CK_LIST_ENTRY(nl_control)		ctl_next;
106 	struct nl_io				ctl_io;
107 	struct rmlock				ctl_lock;
108 };
109 VNET_DECLARE(struct nl_control *, nl_ctl);
110 #define	V_nl_ctl	VNET(nl_ctl)
111 
112 
113 struct sockaddr_nl;
114 struct sockaddr;
115 struct nlmsghdr;
116 
117 /* netlink_module.c */
118 struct nl_control *vnet_nl_ctl_init(void);
119 
120 int nl_verify_proto(int proto);
121 const char *nl_get_proto_name(int proto);
122 
123 extern int netlink_unloading;
124 
125 struct nl_proto_handler {
126 	nl_handler_f	cb;
127 	const char	*proto_name;
128 };
129 extern struct nl_proto_handler *nl_handlers;
130 
131 /* netlink_domain.c */
132 void nl_send_group(struct mbuf *m, int cnt, int proto, int group_id);
133 
134 /* netlink_io.c */
135 #define	NL_IOF_UNTRANSLATED	0x01
136 #define	NL_IOF_IGNORE_LIMIT	0x02
137 bool nl_send_one(struct mbuf *m, struct nlpcb *nlp, int cnt, int io_flags);
138 void nlmsg_ack(struct nlpcb *nlp, int error, struct nlmsghdr *nlmsg,
139     struct nl_pstate *npt);
140 void nl_on_transmit(struct nlpcb *nlp);
141 void nl_init_io(struct nlpcb *nlp);
142 void nl_free_io(struct nlpcb *nlp);
143 
144 void nl_taskqueue_handler(void *_arg, int pending);
145 int nl_receive_async(struct mbuf *m, struct socket *so);
146 void nl_process_receive_locked(struct nlpcb *nlp);
147 
148 /* netlink_generic.c */
149 struct genl_family {
150 	const char	*family_name;
151 	uint16_t	family_hdrsize;
152 	uint16_t	family_id;
153 	uint16_t	family_version;
154 	uint16_t	family_attr_max;
155 	uint16_t	family_cmd_size;
156 	uint16_t	family_num_groups;
157 	struct genl_cmd	*family_cmds;
158 };
159 
160 struct genl_group {
161 	struct genl_family	*group_family;
162 	const char		*group_name;
163 };
164 
165 struct genl_family *genl_get_family(uint32_t family_id);
166 struct genl_group *genl_get_group(uint32_t group_id);
167 
168 #define	MAX_FAMILIES	20
169 #define	MAX_GROUPS	64
170 
171 #define	MIN_GROUP_NUM	48
172 
173 #define	CTRL_FAMILY_NAME	"nlctrl"
174 
175 struct ifnet;
176 struct nl_parsed_link;
177 struct nlattr_bmask;
178 struct nl_pstate;
179 
180 /* Function map */
181 struct nl_function_wrapper {
182 	bool (*nlmsg_add)(struct nl_writer *nw, uint32_t portid, uint32_t seq, uint16_t type,
183 	    uint16_t flags, uint32_t len);
184 	bool (*nlmsg_refill_buffer)(struct nl_writer *nw, int required_len);
185 	bool (*nlmsg_flush)(struct nl_writer *nw);
186 	bool (*nlmsg_end)(struct nl_writer *nw);
187 	void (*nlmsg_abort)(struct nl_writer *nw);
188 	void (*nlmsg_ignore_limit)(struct nl_writer *nw);
189 	bool (*nlmsg_get_unicast_writer)(struct nl_writer *nw, int size, struct nlpcb *nlp);
190 	bool (*nlmsg_get_group_writer)(struct nl_writer *nw, int size, int protocol, int group_id);
191 	bool (*nlmsg_get_chain_writer)(struct nl_writer *nw, int size, struct mbuf **pm);
192 	bool (*nlmsg_end_dump)(struct nl_writer *nw, int error, struct nlmsghdr *hdr);
193 	int (*nl_modify_ifp_generic)(struct ifnet *ifp, struct nl_parsed_link *lattrs,
194 	    const struct nlattr_bmask *bm, struct nl_pstate *npt);
195 	void (*nl_store_ifp_cookie)(struct nl_pstate *npt, struct ifnet *ifp);
196 };
197 void nl_set_functions(const struct nl_function_wrapper *nl);
198 
199 
200 
201 #endif
202 #endif
203