1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
|
#ifndef _CCID_H
#define _CCID_H
/*
* net/dccp/ccid.h
*
* An implementation of the DCCP protocol
* Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*
* CCID infrastructure
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <net/sock.h>
#include <linux/compiler.h>
#include <linux/dccp.h>
#include <linux/list.h>
#include <linux/module.h>
/* maximum value for a CCID (RFC 4340, 19.5) */
#define CCID_MAX 255
#define CCID_SLAB_NAME_LENGTH 32
struct tcp_info;
/**
* struct ccid_operations - Interface to Congestion-Control Infrastructure
*
* @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.)
* @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled)
* @ccid_name: alphabetical identifier string for @ccid_id
* @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection
* @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket
*
* @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup)
* @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction)
* @ccid_hc_rx_packet_recv: implements the HC-receiver side
* @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options
* @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options
* @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender
* @ccid_hc_tx_send_packet: implements the sending part of the HC-sender
* @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender
* @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender
* @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender
*/
struct ccid_operations {
unsigned char ccid_id;
__u32 ccid_ccmps;
const char *ccid_name;
struct kmem_cache *ccid_hc_rx_slab,
*ccid_hc_tx_slab;
char ccid_hc_rx_slab_name[CCID_SLAB_NAME_LENGTH];
char ccid_hc_tx_slab_name[CCID_SLAB_NAME_LENGTH];
__u32 ccid_hc_rx_obj_size,
ccid_hc_tx_obj_size;
/* Interface Routines */
int (*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk);
int (*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk);
void (*ccid_hc_rx_exit)(struct sock *sk);
void (*ccid_hc_tx_exit)(struct sock *sk);
void (*ccid_hc_rx_packet_recv)(struct sock *sk,
struct sk_buff *skb);
int (*ccid_hc_rx_parse_options)(struct sock *sk, u8 pkt,
u8 opt, u8 *val, u8 len);
int (*ccid_hc_rx_insert_options)(struct sock *sk,
struct sk_buff *skb);
void (*ccid_hc_tx_packet_recv)(struct sock *sk,
struct sk_buff *skb);
int (*ccid_hc_tx_parse_options)(struct sock *sk, u8 pkt,
u8 opt, u8 *val, u8 len);
int (*ccid_hc_tx_send_packet)(struct sock *sk,
struct sk_buff *skb);
void (*ccid_hc_tx_packet_sent)(struct sock *sk,
unsigned int len);
void (*ccid_hc_rx_get_info)(struct sock *sk,
struct tcp_info *info);
void (*ccid_hc_tx_get_info)(struct sock *sk,
struct tcp_info *info);
int (*ccid_hc_rx_getsockopt)(struct sock *sk,
const int optname, int len,
u32 __user *optval,
int __user *optlen);
int (*ccid_hc_tx_getsockopt)(struct sock *sk,
const int optname, int len,
u32 __user *optval,
int __user *optlen);
};
extern struct ccid_operations ccid2_ops;
#ifdef CONFIG_IP_DCCP_CCID3
extern struct ccid_operations ccid3_ops;
#endif
int ccid_initialize_builtins(void);
void ccid_cleanup_builtins(void);
struct ccid {
struct ccid_operations *ccid_ops;
char ccid_priv[0];
};
static inline void *ccid_priv(const struct ccid *ccid)
{
return (void *)ccid->ccid_priv;
}
bool ccid_support_check(u8 const *ccid_array, u8 array_len);
int ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len);
int ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
char __user *, int __user *);
struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx);
static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp)
{
struct ccid *ccid = dp->dccps_hc_rx_ccid;
if (ccid == NULL || ccid->ccid_ops == NULL)
return -1;
return ccid->ccid_ops->ccid_id;
}
static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp)
{
struct ccid *ccid = dp->dccps_hc_tx_ccid;
if (ccid == NULL || ccid->ccid_ops == NULL)
return -1;
return ccid->ccid_ops->ccid_id;
}
void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk);
/*
* Congestion control of queued data packets via CCID decision.
*
* The TX CCID performs its congestion-control by indicating whether and when a
* queued packet may be sent, using the return code of ccid_hc_tx_send_packet().
* The following modes are supported via the symbolic constants below:
* - timer-based pacing (CCID returns a delay value in milliseconds);
* - autonomous dequeueing (CCID internally schedules dccps_xmitlet).
*/
enum ccid_dequeueing_decision {
CCID_PACKET_SEND_AT_ONCE = 0x00000, /* "green light": no delay */
CCID_PACKET_DELAY_MAX = 0x0FFFF, /* maximum delay in msecs */
CCID_PACKET_DELAY = 0x10000, /* CCID msec-delay mode */
CCID_PACKET_WILL_DEQUEUE_LATER = 0x20000, /* CCID autonomous mode */
CCID_PACKET_ERR = 0xF0000, /* error condition */
};
static inline int ccid_packet_dequeue_eval(const int return_code)
{
if (return_code < 0)
return CCID_PACKET_ERR;
if (return_code == 0)
return CCID_PACKET_SEND_AT_ONCE;
if (return_code <= CCID_PACKET_DELAY_MAX)
return CCID_PACKET_DELAY;
return return_code;
}
static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
struct sk_buff *skb)
{
if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL)
return ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
return CCID_PACKET_SEND_AT_ONCE;
}
static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
unsigned int len)
{
if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL)
ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, len);
}
static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk,
struct sk_buff *skb)
{
if (ccid->ccid_ops->ccid_hc_rx_packet_recv != NULL)
ccid->ccid_ops->ccid_hc_rx_packet_recv(sk, skb);
}
static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk,
struct sk_buff *skb)
{
if (ccid->ccid_ops->ccid_hc_tx_packet_recv != NULL)
ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb);
}
/**
* ccid_hc_tx_parse_options - Parse CCID-specific options sent by the receiver
* @pkt: type of packet that @opt appears on (RFC 4340, 5.1)
* @opt: the CCID-specific option type (RFC 4340, 5.8 and 10.3)
* @val: value of @opt
* @len: length of @val in bytes
*/
static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk,
u8 pkt, u8 opt, u8 *val, u8 len)
{
if (ccid->ccid_ops->ccid_hc_tx_parse_options == NULL)
return 0;
return ccid->ccid_ops->ccid_hc_tx_parse_options(sk, pkt, opt, val, len);
}
/**
* ccid_hc_rx_parse_options - Parse CCID-specific options sent by the sender
* Arguments are analogous to ccid_hc_tx_parse_options()
*/
static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk,
u8 pkt, u8 opt, u8 *val, u8 len)
{
if (ccid->ccid_ops->ccid_hc_rx_parse_options == NULL)
return 0;
return ccid->ccid_ops->ccid_hc_rx_parse_options(sk, pkt, opt, val, len);
}
static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,
struct sk_buff *skb)
{
if (ccid->ccid_ops->ccid_hc_rx_insert_options != NULL)
return ccid->ccid_ops->ccid_hc_rx_insert_options(sk, skb);
return 0;
}
static inline void ccid_hc_rx_get_info(struct ccid *ccid, struct sock *sk,
struct tcp_info *info)
{
if (ccid->ccid_ops->ccid_hc_rx_get_info != NULL)
ccid->ccid_ops->ccid_hc_rx_get_info(sk, info);
}
static inline void ccid_hc_tx_get_info(struct ccid *ccid, struct sock *sk,
struct tcp_info *info)
{
if (ccid->ccid_ops->ccid_hc_tx_get_info != NULL)
ccid->ccid_ops->ccid_hc_tx_get_info(sk, info);
}
static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk,
const int optname, int len,
u32 __user *optval, int __user *optlen)
{
int rc = -ENOPROTOOPT;
if (ccid != NULL && ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL)
rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len,
optval, optlen);
return rc
|