1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * L2TP-over-IP socket for L2TPv3.
4  *
5  * Author: James Chapman <jchapman@katalix.com>
6  */
7 
8 #ifndef _LINUX_L2TP_H_
9 #define _LINUX_L2TP_H_
10 
11 #include <linux/types.h>
12 #include <linux/socket.h>
13 #include <linux/in.h>
14 #include <linux/in6.h>
15 
16 #define IPPROTO_L2TP		115
17 
18 /**
19  * struct sockaddr_l2tpip - the sockaddr structure for L2TP-over-IP sockets
20  * @l2tp_family:  address family number AF_L2TPIP.
21  * @l2tp_addr:    protocol specific address information
22  * @l2tp_conn_id: connection id of tunnel
23  */
24 #define __SOCK_SIZE__	16		/* sizeof(struct sockaddr)	*/
25 struct sockaddr_l2tpip {
26 	/* The first fields must match struct sockaddr_in */
27 	__kernel_sa_family_t l2tp_family; /* AF_INET */
28 	__be16		l2tp_unused;	/* INET port number (unused) */
29 	struct in_addr	l2tp_addr;	/* Internet address */
30 
31 	__u32		l2tp_conn_id;	/* Connection ID of tunnel */
32 
33 	/* Pad to size of `struct sockaddr'. */
34 	unsigned char	__pad[__SOCK_SIZE__ -
35 			      sizeof(__kernel_sa_family_t) -
36 			      sizeof(__be16) - sizeof(struct in_addr) -
37 			      sizeof(__u32)];
38 };
39 
40 /**
41  * struct sockaddr_l2tpip6 - the sockaddr structure for L2TP-over-IPv6 sockets
42  * @l2tp_family:  address family number AF_L2TPIP.
43  * @l2tp_addr:    protocol specific address information
44  * @l2tp_conn_id: connection id of tunnel
45  */
46 struct sockaddr_l2tpip6 {
47 	/* The first fields must match struct sockaddr_in6 */
48 	__kernel_sa_family_t l2tp_family; /* AF_INET6 */
49 	__be16		l2tp_unused;	/* INET port number (unused) */
50 	__be32		l2tp_flowinfo;	/* IPv6 flow information */
51 	struct in6_addr	l2tp_addr;	/* IPv6 address */
52 	__u32		l2tp_scope_id;	/* scope id (new in RFC2553) */
53 	__u32		l2tp_conn_id;	/* Connection ID of tunnel */
54 };
55 
56 /*****************************************************************************
57  *  NETLINK_GENERIC netlink family.
58  *****************************************************************************/
59 
60 /*
61  * Commands.
62  * Valid TLVs of each command are:-
63  * TUNNEL_CREATE	- CONN_ID, pw_type, netns, ifname, ipinfo, udpinfo, udpcsum, vlanid
64  * TUNNEL_DELETE	- CONN_ID
65  * TUNNEL_MODIFY	- CONN_ID, udpcsum
66  * TUNNEL_GETSTATS	- CONN_ID, (stats)
67  * TUNNEL_GET		- CONN_ID, (...)
68  * SESSION_CREATE	- SESSION_ID, PW_TYPE, offset, data_seq, cookie, peer_cookie, offset, l2spec
69  * SESSION_DELETE	- SESSION_ID
70  * SESSION_MODIFY	- SESSION_ID, data_seq
71  * SESSION_GET		- SESSION_ID, (...)
72  * SESSION_GETSTATS	- SESSION_ID, (stats)
73  *
74  */
75 enum {
76 	L2TP_CMD_NOOP,
77 	L2TP_CMD_TUNNEL_CREATE,
78 	L2TP_CMD_TUNNEL_DELETE,
79 	L2TP_CMD_TUNNEL_MODIFY,
80 	L2TP_CMD_TUNNEL_GET,
81 	L2TP_CMD_SESSION_CREATE,
82 	L2TP_CMD_SESSION_DELETE,
83 	L2TP_CMD_SESSION_MODIFY,
84 	L2TP_CMD_SESSION_GET,
85 	__L2TP_CMD_MAX,
86 };
87 
88 #define L2TP_CMD_MAX			(__L2TP_CMD_MAX - 1)
89 
90 /*
91  * ATTR types defined for L2TP
92  */
93 enum {
94 	L2TP_ATTR_NONE,			/* no data */
95 	L2TP_ATTR_PW_TYPE,		/* u16, enum l2tp_pwtype */
96 	L2TP_ATTR_ENCAP_TYPE,		/* u16, enum l2tp_encap_type */
97 	L2TP_ATTR_OFFSET,		/* u16 */
98 	L2TP_ATTR_DATA_SEQ,		/* u16 */
99 	L2TP_ATTR_L2SPEC_TYPE,		/* u8, enum l2tp_l2spec_type */
100 	L2TP_ATTR_L2SPEC_LEN,		/* u8, enum l2tp_l2spec_type */
101 	L2TP_ATTR_PROTO_VERSION,	/* u8 */
102 	L2TP_ATTR_IFNAME,		/* string */
103 	L2TP_ATTR_CONN_ID,		/* u32 */
104 	L2TP_ATTR_PEER_CONN_ID,		/* u32 */
105 	L2TP_ATTR_SESSION_ID,		/* u32 */
106 	L2TP_ATTR_PEER_SESSION_ID,	/* u32 */
107 	L2TP_ATTR_UDP_CSUM,		/* u8 */
108 	L2TP_ATTR_VLAN_ID,		/* u16 */
109 	L2TP_ATTR_COOKIE,		/* 0, 4 or 8 bytes */
110 	L2TP_ATTR_PEER_COOKIE,		/* 0, 4 or 8 bytes */
111 	L2TP_ATTR_DEBUG,		/* u32, enum l2tp_debug_flags */
112 	L2TP_ATTR_RECV_SEQ,		/* u8 */
113 	L2TP_ATTR_SEND_SEQ,		/* u8 */
114 	L2TP_ATTR_LNS_MODE,		/* u8 */
115 	L2TP_ATTR_USING_IPSEC,		/* u8 */
116 	L2TP_ATTR_RECV_TIMEOUT,		/* msec */
117 	L2TP_ATTR_FD,			/* int */
118 	L2TP_ATTR_IP_SADDR,		/* u32 */
119 	L2TP_ATTR_IP_DADDR,		/* u32 */
120 	L2TP_ATTR_UDP_SPORT,		/* u16 */
121 	L2TP_ATTR_UDP_DPORT,		/* u16 */
122 	L2TP_ATTR_MTU,			/* u16 */
123 	L2TP_ATTR_MRU,			/* u16 */
124 	L2TP_ATTR_STATS,		/* nested */
125 	L2TP_ATTR_IP6_SADDR,		/* struct in6_addr */
126 	L2TP_ATTR_IP6_DADDR,		/* struct in6_addr */
127 	L2TP_ATTR_UDP_ZERO_CSUM6_TX,	/* flag */
128 	L2TP_ATTR_UDP_ZERO_CSUM6_RX,	/* flag */
129 	L2TP_ATTR_PAD,
130 	__L2TP_ATTR_MAX,
131 };
132 
133 #define L2TP_ATTR_MAX			(__L2TP_ATTR_MAX - 1)
134 
135 /* Nested in L2TP_ATTR_STATS */
136 enum {
137 	L2TP_ATTR_STATS_NONE,		/* no data */
138 	L2TP_ATTR_TX_PACKETS,		/* u64 */
139 	L2TP_ATTR_TX_BYTES,		/* u64 */
140 	L2TP_ATTR_TX_ERRORS,		/* u64 */
141 	L2TP_ATTR_RX_PACKETS,		/* u64 */
142 	L2TP_ATTR_RX_BYTES,		/* u64 */
143 	L2TP_ATTR_RX_SEQ_DISCARDS,	/* u64 */
144 	L2TP_ATTR_RX_OOS_PACKETS,	/* u64 */
145 	L2TP_ATTR_RX_ERRORS,		/* u64 */
146 	L2TP_ATTR_STATS_PAD,
147 	__L2TP_ATTR_STATS_MAX,
148 };
149 
150 #define L2TP_ATTR_STATS_MAX		(__L2TP_ATTR_STATS_MAX - 1)
151 
152 enum l2tp_pwtype {
153 	L2TP_PWTYPE_NONE = 0x0000,
154 	L2TP_PWTYPE_ETH_VLAN = 0x0004,
155 	L2TP_PWTYPE_ETH = 0x0005,
156 	L2TP_PWTYPE_PPP = 0x0007,
157 	L2TP_PWTYPE_PPP_AC = 0x0008,
158 	L2TP_PWTYPE_IP = 0x000b,
159 	__L2TP_PWTYPE_MAX
160 };
161 
162 enum l2tp_l2spec_type {
163 	L2TP_L2SPECTYPE_NONE,
164 	L2TP_L2SPECTYPE_DEFAULT,
165 };
166 
167 enum l2tp_encap_type {
168 	L2TP_ENCAPTYPE_UDP,
169 	L2TP_ENCAPTYPE_IP,
170 };
171 
172 enum l2tp_seqmode {
173 	L2TP_SEQ_NONE = 0,
174 	L2TP_SEQ_IP = 1,
175 	L2TP_SEQ_ALL = 2,
176 };
177 
178 /**
179  * enum l2tp_debug_flags - debug message categories for L2TP tunnels/sessions
180  *
181  * @L2TP_MSG_DEBUG: verbose debug (if compiled in)
182  * @L2TP_MSG_CONTROL: userspace - kernel interface
183  * @L2TP_MSG_SEQ: sequence numbers
184  * @L2TP_MSG_DATA: data packets
185  */
186 enum l2tp_debug_flags {
187 	L2TP_MSG_DEBUG		= (1 << 0),
188 	L2TP_MSG_CONTROL	= (1 << 1),
189 	L2TP_MSG_SEQ		= (1 << 2),
190 	L2TP_MSG_DATA		= (1 << 3),
191 };
192 
193 /*
194  * NETLINK_GENERIC related info
195  */
196 #define L2TP_GENL_NAME		"l2tp"
197 #define L2TP_GENL_VERSION	0x1
198 #define L2TP_GENL_MCGROUP       "l2tp"
199 
200 #endif /* _LINUX_L2TP_H_ */
201