1 /*
2  * net/tipc/bearer.h: Include file for TIPC bearer code
3  *
4  * Copyright (c) 1996-2006, 2013-2016, Ericsson AB
5  * Copyright (c) 2005, 2010-2011, Wind River Systems
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the names of the copyright holders nor the names of its
17  *    contributors may be used to endorse or promote products derived from
18  *    this software without specific prior written permission.
19  *
20  * Alternatively, this software may be distributed under the terms of the
21  * GNU General Public License ("GPL") version 2 as published by the Free
22  * Software Foundation.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34  * POSSIBILITY OF SUCH DAMAGE.
35  */
36 
37 #ifndef _TIPC_BEARER_H
38 #define _TIPC_BEARER_H
39 
40 #include "netlink.h"
41 #include "core.h"
42 #include "msg.h"
43 #include <net/genetlink.h>
44 
45 #define MAX_MEDIA	3
46 
47 /* Identifiers associated with TIPC message header media address info
48  * - address info field is 32 bytes long
49  * - the field's actual content and length is defined per media
50  * - remaining unused bytes in the field are set to zero
51  */
52 #define TIPC_MEDIA_INFO_SIZE	32
53 #define TIPC_MEDIA_TYPE_OFFSET	3
54 #define TIPC_MEDIA_ADDR_OFFSET	4
55 
56 /*
57  * Identifiers of supported TIPC media types
58  */
59 #define TIPC_MEDIA_TYPE_ETH	1
60 #define TIPC_MEDIA_TYPE_IB	2
61 #define TIPC_MEDIA_TYPE_UDP	3
62 
63 /* Minimum bearer MTU */
64 #define TIPC_MIN_BEARER_MTU	(MAX_H_SIZE + INT_H_SIZE)
65 
66 /* Identifiers for distinguishing between broadcast/multicast and replicast
67  */
68 #define TIPC_BROADCAST_SUPPORT  1
69 #define TIPC_REPLICAST_SUPPORT  2
70 
71 /**
72  * struct tipc_media_addr - destination address used by TIPC bearers
73  * @value: address info (format defined by media)
74  * @media_id: TIPC media type identifier
75  * @broadcast: non-zero if address is a broadcast address
76  */
77 struct tipc_media_addr {
78 	u8 value[TIPC_MEDIA_INFO_SIZE];
79 	u8 media_id;
80 	u8 broadcast;
81 };
82 
83 struct tipc_bearer;
84 
85 /**
86  * struct tipc_media - Media specific info exposed to generic bearer layer
87  * @send_msg: routine which handles buffer transmission
88  * @enable_media: routine which enables a media
89  * @disable_media: routine which disables a media
90  * @addr2str: convert media address format to string
91  * @addr2msg: convert from media addr format to discovery msg addr format
92  * @msg2addr: convert from discovery msg addr format to media addr format
93  * @raw2addr: convert from raw addr format to media addr format
94  * @priority: default link (and bearer) priority
95  * @tolerance: default time (in ms) before declaring link failure
96  * @min_win: minimum window (in packets) before declaring link congestion
97  * @max_win: maximum window (in packets) before declaring link congestion
98  * @mtu: max packet size bearer can support for media type not dependent on
99  * underlying device MTU
100  * @type_id: TIPC media identifier
101  * @hwaddr_len: TIPC media address len
102  * @name: media name
103  */
104 struct tipc_media {
105 	int (*send_msg)(struct net *net, struct sk_buff *buf,
106 			struct tipc_bearer *b,
107 			struct tipc_media_addr *dest);
108 	int (*enable_media)(struct net *net, struct tipc_bearer *b,
109 			    struct nlattr *attr[]);
110 	void (*disable_media)(struct tipc_bearer *b);
111 	int (*addr2str)(struct tipc_media_addr *addr,
112 			char *strbuf,
113 			int bufsz);
114 	int (*addr2msg)(char *msg, struct tipc_media_addr *addr);
115 	int (*msg2addr)(struct tipc_bearer *b,
116 			struct tipc_media_addr *addr,
117 			char *msg);
118 	int (*raw2addr)(struct tipc_bearer *b,
119 			struct tipc_media_addr *addr,
120 			const char *raw);
121 	u32 priority;
122 	u32 tolerance;
123 	u32 min_win;
124 	u32 max_win;
125 	u32 mtu;
126 	u32 type_id;
127 	u32 hwaddr_len;
128 	char name[TIPC_MAX_MEDIA_NAME];
129 };
130 
131 /**
132  * struct tipc_bearer - Generic TIPC bearer structure
133  * @media_ptr: pointer to additional media-specific information about bearer
134  * @mtu: max packet size bearer can support
135  * @addr: media-specific address associated with bearer
136  * @name: bearer name (format = media:interface)
137  * @media: ptr to media structure associated with bearer
138  * @bcast_addr: media address used in broadcasting
139  * @pt: packet type for bearer
140  * @rcu: rcu struct for tipc_bearer
141  * @priority: default link priority for bearer
142  * @min_win: minimum window (in packets) before declaring link congestion
143  * @max_win: maximum window (in packets) before declaring link congestion
144  * @tolerance: default link tolerance for bearer
145  * @domain: network domain to which links can be established
146  * @identity: array index of this bearer within TIPC bearer array
147  * @disc: ptr to link setup request
148  * @net_plane: network plane ('A' through 'H') currently associated with bearer
149  * @up: bearer up flag (bit 0)
150  * @refcnt: tipc_bearer reference counter
151  *
152  * Note: media-specific code is responsible for initialization of the fields
153  * indicated below when a bearer is enabled; TIPC's generic bearer code takes
154  * care of initializing all other fields.
155  */
156 struct tipc_bearer {
157 	void __rcu *media_ptr;			/* initialized by media */
158 	u32 mtu;				/* initialized by media */
159 	struct tipc_media_addr addr;		/* initialized by media */
160 	char name[TIPC_MAX_BEARER_NAME];
161 	struct tipc_media *media;
162 	struct tipc_media_addr bcast_addr;
163 	struct packet_type pt;
164 	struct rcu_head rcu;
165 	u32 priority;
166 	u32 min_win;
167 	u32 max_win;
168 	u32 tolerance;
169 	u32 domain;
170 	u32 identity;
171 	struct tipc_discoverer *disc;
172 	char net_plane;
173 	unsigned long up;
174 	refcount_t refcnt;
175 };
176 
177 struct tipc_bearer_names {
178 	char media_name[TIPC_MAX_MEDIA_NAME];
179 	char if_name[TIPC_MAX_IF_NAME];
180 };
181 
182 /*
183  * TIPC routines available to supported media types
184  */
185 
186 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b);
187 
188 /*
189  * Routines made available to TIPC by supported media types
190  */
191 extern struct tipc_media eth_media_info;
192 
193 #ifdef CONFIG_TIPC_MEDIA_IB
194 extern struct tipc_media ib_media_info;
195 #endif
196 #ifdef CONFIG_TIPC_MEDIA_UDP
197 extern struct tipc_media udp_media_info;
198 #endif
199 
200 int tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info);
201 int __tipc_nl_bearer_disable(struct sk_buff *skb, struct genl_info *info);
202 int tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info);
203 int __tipc_nl_bearer_enable(struct sk_buff *skb, struct genl_info *info);
204 int tipc_nl_bearer_dump(struct sk_buff *skb, struct netlink_callback *cb);
205 int tipc_nl_bearer_get(struct sk_buff *skb, struct genl_info *info);
206 int tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info);
207 int __tipc_nl_bearer_set(struct sk_buff *skb, struct genl_info *info);
208 int tipc_nl_bearer_add(struct sk_buff *skb, struct genl_info *info);
209 
210 int tipc_nl_media_dump(struct sk_buff *skb, struct netlink_callback *cb);
211 int tipc_nl_media_get(struct sk_buff *skb, struct genl_info *info);
212 int tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info);
213 int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info);
214 
215 int tipc_media_set_priority(const char *name, u32 new_value);
216 int tipc_media_set_window(const char *name, u32 new_value);
217 int tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a);
218 int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b,
219 			 struct nlattr *attrs[]);
220 bool tipc_bearer_hold(struct tipc_bearer *b);
221 void tipc_bearer_put(struct tipc_bearer *b);
222 void tipc_disable_l2_media(struct tipc_bearer *b);
223 int tipc_l2_send_msg(struct net *net, struct sk_buff *buf,
224 		     struct tipc_bearer *b, struct tipc_media_addr *dest);
225 
226 void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest);
227 void tipc_bearer_remove_dest(struct net *net, u32 bearer_id, u32 dest);
228 struct tipc_bearer *tipc_bearer_find(struct net *net, const char *name);
229 int tipc_bearer_get_name(struct net *net, char *name, u32 bearer_id);
230 struct tipc_media *tipc_media_find(const char *name);
231 int tipc_bearer_setup(void);
232 void tipc_bearer_cleanup(void);
233 void tipc_bearer_stop(struct net *net);
234 int tipc_bearer_mtu(struct net *net, u32 bearer_id);
235 bool tipc_bearer_bcast_support(struct net *net, u32 bearer_id);
236 void tipc_bearer_xmit_skb(struct net *net, u32 bearer_id,
237 			  struct sk_buff *skb,
238 			  struct tipc_media_addr *dest);
239 void tipc_bearer_xmit(struct net *net, u32 bearer_id,
240 		      struct sk_buff_head *xmitq,
241 		      struct tipc_media_addr *dst,
242 		      struct tipc_node *__dnode);
243 void tipc_bearer_bc_xmit(struct net *net, u32 bearer_id,
244 			 struct sk_buff_head *xmitq);
245 void tipc_clone_to_loopback(struct net *net, struct sk_buff_head *pkts);
246 int tipc_attach_loopback(struct net *net);
247 void tipc_detach_loopback(struct net *net);
248 
tipc_loopback_trace(struct net * net,struct sk_buff_head * pkts)249 static inline void tipc_loopback_trace(struct net *net,
250 				       struct sk_buff_head *pkts)
251 {
252 	if (unlikely(dev_nit_active(net->loopback_dev)))
253 		tipc_clone_to_loopback(net, pkts);
254 }
255 
256 /* check if device MTU is too low for tipc headers */
tipc_mtu_bad(struct net_device * dev,unsigned int reserve)257 static inline bool tipc_mtu_bad(struct net_device *dev, unsigned int reserve)
258 {
259 	if (dev->mtu >= TIPC_MIN_BEARER_MTU + reserve)
260 		return false;
261 	netdev_warn(dev, "MTU too low for tipc bearer\n");
262 	return true;
263 }
264 
265 #endif	/* _TIPC_BEARER_H */
266