1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  net/dccp/sysctl.c
4  *
5  *  An implementation of the DCCP protocol
6  *  Arnaldo Carvalho de Melo <acme@mandriva.com>
7  */
8 
9 #include <linux/mm.h>
10 #include <linux/sysctl.h>
11 #include "dccp.h"
12 #include "feat.h"
13 
14 #ifndef CONFIG_SYSCTL
15 #error This file should not be compiled without CONFIG_SYSCTL defined
16 #endif
17 
18 /* Boundary values */
19 static int		u8_max   = 0xFF;
20 static unsigned long	seqw_min = DCCPF_SEQ_WMIN,
21 			seqw_max = 0xFFFFFFFF;		/* maximum on 32 bit */
22 
23 static struct ctl_table dccp_default_table[] = {
24 	{
25 		.procname	= "seq_window",
26 		.data		= &sysctl_dccp_sequence_window,
27 		.maxlen		= sizeof(sysctl_dccp_sequence_window),
28 		.mode		= 0644,
29 		.proc_handler	= proc_doulongvec_minmax,
30 		.extra1		= &seqw_min,		/* RFC 4340, 7.5.2 */
31 		.extra2		= &seqw_max,
32 	},
33 	{
34 		.procname	= "rx_ccid",
35 		.data		= &sysctl_dccp_rx_ccid,
36 		.maxlen		= sizeof(sysctl_dccp_rx_ccid),
37 		.mode		= 0644,
38 		.proc_handler	= proc_dointvec_minmax,
39 		.extra1		= SYSCTL_ZERO,
40 		.extra2		= &u8_max,		/* RFC 4340, 10. */
41 	},
42 	{
43 		.procname	= "tx_ccid",
44 		.data		= &sysctl_dccp_tx_ccid,
45 		.maxlen		= sizeof(sysctl_dccp_tx_ccid),
46 		.mode		= 0644,
47 		.proc_handler	= proc_dointvec_minmax,
48 		.extra1		= SYSCTL_ZERO,
49 		.extra2		= &u8_max,		/* RFC 4340, 10. */
50 	},
51 	{
52 		.procname	= "request_retries",
53 		.data		= &sysctl_dccp_request_retries,
54 		.maxlen		= sizeof(sysctl_dccp_request_retries),
55 		.mode		= 0644,
56 		.proc_handler	= proc_dointvec_minmax,
57 		.extra1		= SYSCTL_ONE,
58 		.extra2		= &u8_max,
59 	},
60 	{
61 		.procname	= "retries1",
62 		.data		= &sysctl_dccp_retries1,
63 		.maxlen		= sizeof(sysctl_dccp_retries1),
64 		.mode		= 0644,
65 		.proc_handler	= proc_dointvec_minmax,
66 		.extra1		= SYSCTL_ZERO,
67 		.extra2		= &u8_max,
68 	},
69 	{
70 		.procname	= "retries2",
71 		.data		= &sysctl_dccp_retries2,
72 		.maxlen		= sizeof(sysctl_dccp_retries2),
73 		.mode		= 0644,
74 		.proc_handler	= proc_dointvec_minmax,
75 		.extra1		= SYSCTL_ZERO,
76 		.extra2		= &u8_max,
77 	},
78 	{
79 		.procname	= "tx_qlen",
80 		.data		= &sysctl_dccp_tx_qlen,
81 		.maxlen		= sizeof(sysctl_dccp_tx_qlen),
82 		.mode		= 0644,
83 		.proc_handler	= proc_dointvec_minmax,
84 		.extra1		= SYSCTL_ZERO,
85 	},
86 	{
87 		.procname	= "sync_ratelimit",
88 		.data		= &sysctl_dccp_sync_ratelimit,
89 		.maxlen		= sizeof(sysctl_dccp_sync_ratelimit),
90 		.mode		= 0644,
91 		.proc_handler	= proc_dointvec_ms_jiffies,
92 	},
93 
94 	{ }
95 };
96 
97 static struct ctl_table_header *dccp_table_header;
98 
dccp_sysctl_init(void)99 int __init dccp_sysctl_init(void)
100 {
101 	dccp_table_header = register_net_sysctl(&init_net, "net/dccp/default",
102 			dccp_default_table);
103 
104 	return dccp_table_header != NULL ? 0 : -ENOMEM;
105 }
106 
dccp_sysctl_exit(void)107 void dccp_sysctl_exit(void)
108 {
109 	if (dccp_table_header != NULL) {
110 		unregister_net_sysctl_table(dccp_table_header);
111 		dccp_table_header = NULL;
112 	}
113 }
114