xref: /openbsd/sys/ddb/db_usrreq.c (revision d415bd75)
1 /*	$OpenBSD: db_usrreq.c,v 1.22 2021/01/09 20:58:12 gnezdo Exp $	*/
2 
3 /*
4  * Copyright (c) 1996 Michael Shalayeff.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/proc.h>
30 #include <sys/tty.h>
31 #include <sys/sysctl.h>
32 #include <dev/cons.h>
33 
34 #include <ddb/db_var.h>
35 
36 int	db_log = 1;
37 int	db_profile;			/* Allow dynamic profiling */
38 
39 const struct sysctl_bounded_args ddb_vars[] = {
40 	{ DBCTL_RADIX, &db_radix, 8, 16 },
41 	{ DBCTL_MAXWIDTH, &db_max_width, 0, INT_MAX },
42 	{ DBCTL_TABSTOP, &db_tab_stop_width, 1, 16 },
43 	{ DBCTL_MAXLINE, &db_max_line, 0, INT_MAX },
44 	{ DBCTL_LOG, &db_log, 0, 1 },
45 };
46 
47 int
48 ddb_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
49     size_t newlen, struct proc *p)
50 {
51 	/* All sysctl names at this level are terminal. */
52 	if (namelen != 1)
53 		return (ENOTDIR);
54 
55 	switch (name[0]) {
56 	case DBCTL_PANIC:
57 		if (securelevel > 0)
58 			return (sysctl_int_lower(oldp, oldlenp, newp, newlen,
59 			    &db_panic));
60 		else {
61 			return (sysctl_int_bounded(oldp, oldlenp, newp, newlen,
62 			    &db_panic, 0, 1));
63 		}
64 		break;
65 	case DBCTL_CONSOLE:
66 		if (securelevel > 0)
67 			return (sysctl_int_lower(oldp, oldlenp, newp, newlen,
68 			    &db_console));
69 		else {
70 			return (sysctl_int_bounded(oldp, oldlenp, newp, newlen,
71 			    &db_console, 0, 1));
72 		}
73 		break;
74 	case DBCTL_TRIGGER:
75 		if (newp && db_console) {
76 			struct process *pr = curproc->p_p;
77 
78 			if (securelevel < 1 ||
79 			    (pr->ps_flags & PS_CONTROLT && cn_tab &&
80 			    cn_tab->cn_dev == pr->ps_session->s_ttyp->t_dev)) {
81 				db_enter();
82 				newp = NULL;
83 			} else
84 				return (ENODEV);
85 		}
86 		return (sysctl_rdint(oldp, oldlenp, newp, 0));
87 #if defined(DDBPROF)
88 	case DBCTL_PROFILE:
89 		if (securelevel > 0)
90 			return (sysctl_int_lower(oldp, oldlenp, newp, newlen,
91 			    &db_profile));
92 		else {
93 			return (sysctl_int_bounded(oldp, oldlenp, newp, newlen,
94 			    &db_profile, 0, 1));
95 		}
96 		break;
97 #endif /* DDBPROF */
98 	default:
99 		return (sysctl_bounded_arr(ddb_vars, nitems(ddb_vars), name,
100 		    namelen, oldp, oldlenp, newp, newlen));
101 	}
102 	/* NOTREACHED */
103 }
104