On Tue, Apr 27, 2021 at 12:18:02PM -0600, Theo de Raadt wrote:
> Actually, your variation seems pretty good. Is there any reason to not
> use this type of define?
This would look like this.
I think sysctl_int() and sysctl_rdint() should be the primitive
functions. This brings us back the 4.4BSD implementation. Then
sysctl_int_bounded() builds the magic on top like sysctl_int_lower()
does it. sysctl_bounded_arr() is a wrapper around it.
I just added a few defines that my simple grep found. We could
search for more.
bluhm
Index: kern/kern_sysctl.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/kern/kern_sysctl.c,v
retrieving revision 1.390
diff -u -p -r1.390 kern_sysctl.c
--- kern/kern_sysctl.c 23 Apr 2021 07:21:02 -0000 1.390
+++ kern/kern_sysctl.c 27 Apr 2021 19:09:18 -0000
@@ -818,7 +818,8 @@ debug_sysctl(int *name, u_int namelen, v
* Reads, or writes that lower the value
*/
int
-sysctl_int_lower(void *oldp, size_t *oldlenp, void *newp, size_t newlen, int
*valp)
+sysctl_int_lower(void *oldp, size_t *oldlenp, void *newp, size_t newlen,
+ int *valp)
{
unsigned int oval = *valp, val = *valp;
int error;
@@ -841,35 +842,40 @@ sysctl_int_lower(void *oldp, size_t *old
int
sysctl_int(void *oldp, size_t *oldlenp, void *newp, size_t newlen, int *valp)
{
- return (sysctl_int_bounded(oldp, oldlenp, newp, newlen, valp, 0, 0));
-}
-
-int
-sysctl_int_bounded(void *oldp, size_t *oldlenp, void *newp, size_t newlen,
- int *valp, int minimum, int maximum)
-{
int error = 0;
- int val;
if (oldp && *oldlenp < sizeof(int))
return (ENOMEM);
if (newp && newlen != sizeof(int))
return (EINVAL);
*oldlenp = sizeof(int);
- val = *valp;
if (oldp)
- error = copyout(&val, oldp, sizeof(int));
+ error = copyout(valp, oldp, sizeof(int));
if (error == 0 && newp)
- error = copyin(newp, &val, sizeof(int));
- if (error)
- return (error);
- if (minimum == maximum || (minimum <= val && val <= maximum))
- *valp = val;
- else
- error = EINVAL;
+ error = copyin(newp, valp, sizeof(int));
return (error);
}
+int
+sysctl_int_bounded(void *oldp, size_t *oldlenp, void *newp, size_t newlen,
+ int *valp, int minimum, int maximum)
+{
+ int val = *valp;
+ int error;
+
+ /* read only */
+ if (newp == NULL || minimum > maximum)
+ return (sysctl_rdint(oldp, oldlenp, newp, *valp));
+
+ if ((error = sysctl_int(oldp, oldlenp, newp, newlen, &val)))
+ return (error);
+ /* bounded and not within limits */
+ if (minimum < maximum && (val < minimum || maximum < val))
+ return (EINVAL);
+ *valp = val;
+ return (0);
+}
+
/*
* As above, but read-only.
*/
@@ -901,14 +907,8 @@ sysctl_bounded_arr(const struct sysctl_b
return (ENOTDIR);
for (i = 0; i < valplen; ++i) {
if (valpp[i].mib == name[0]) {
- if (valpp[i].minimum <= valpp[i].maximum) {
- return (sysctl_int_bounded(oldp, oldlenp, newp,
- newlen, valpp[i].var, valpp[i].minimum,
- valpp[i].maximum));
- } else {
- return (sysctl_rdint(oldp, oldlenp, newp,
- *valpp[i].var));
- }
+ return (sysctl_int_bounded(oldp, oldlenp, newp, newlen,
+ valpp[i].var, valpp[i].minimum, valpp[i].maximum));
}
}
return (EOPNOTSUPP);
Index: kern/kern_tc.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/kern/kern_tc.c,v
retrieving revision 1.71
diff -u -p -r1.71 kern_tc.c
--- kern/kern_tc.c 23 Feb 2021 04:44:31 -0000 1.71
+++ kern/kern_tc.c 27 Apr 2021 18:57:29 -0000
@@ -829,7 +829,7 @@ inittimecounter(void)
}
const struct sysctl_bounded_args tc_vars[] = {
- { KERN_TIMECOUNTER_TICK, &tc_tick, 1, 0 },
+ { KERN_TIMECOUNTER_TICK, &tc_tick, SYSCTL_INT_READONLY },
{ KERN_TIMECOUNTER_TIMESTEPWARNINGS, ×tepwarnings, 0, 1 },
};
Index: kern/sysv_sem.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/kern/sysv_sem.c,v
retrieving revision 1.60
diff -u -p -r1.60 sysv_sem.c
--- kern/sysv_sem.c 17 Nov 2020 03:23:54 -0000 1.60
+++ kern/sysv_sem.c 27 Apr 2021 18:57:33 -0000
@@ -860,10 +860,10 @@ sema_reallocate(int val)
}
const struct sysctl_bounded_args sysvsem_vars[] = {
- { KERN_SEMINFO_SEMUME, &seminfo.semume, 1, 0 },
- { KERN_SEMINFO_SEMUSZ, &seminfo.semusz, 1, 0 },
- { KERN_SEMINFO_SEMVMX, &seminfo.semvmx, 1, 0 },
- { KERN_SEMINFO_SEMAEM, &seminfo.semaem, 1, 0 },
+ { KERN_SEMINFO_SEMUME, &seminfo.semume, SYSCTL_INT_READONLY },
+ { KERN_SEMINFO_SEMUSZ, &seminfo.semusz, SYSCTL_INT_READONLY },
+ { KERN_SEMINFO_SEMVMX, &seminfo.semvmx, SYSCTL_INT_READONLY },
+ { KERN_SEMINFO_SEMAEM, &seminfo.semaem, SYSCTL_INT_READONLY },
{ KERN_SEMINFO_SEMOPM, &seminfo.semopm, 1, INT_MAX },
};
Index: netinet/ip_input.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/ip_input.c,v
retrieving revision 1.358
diff -u -p -r1.358 ip_input.c
--- netinet/ip_input.c 23 Apr 2021 21:55:36 -0000 1.358
+++ netinet/ip_input.c 27 Apr 2021 18:57:42 -0000
@@ -113,7 +113,7 @@ extern int ip_mrtproto;
const struct sysctl_bounded_args ipctl_vars[] = {
#ifdef MROUTING
- { IPCTL_MRTPROTO, &ip_mrtproto, 1, 0 },
+ { IPCTL_MRTPROTO, &ip_mrtproto, SYSCTL_INT_READONLY },
#endif
{ IPCTL_FORWARDING, &ipforwarding, 0, 2 },
{ IPCTL_SENDREDIRECTS, &ipsendredirects, 0, 1 },
Index: netinet/tcp_usrreq.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/tcp_usrreq.c,v
retrieving revision 1.180
diff -u -p -r1.180 tcp_usrreq.c
--- netinet/tcp_usrreq.c 10 Mar 2021 10:21:49 -0000 1.180
+++ netinet/tcp_usrreq.c 27 Apr 2021 18:57:51 -0000
@@ -112,7 +112,7 @@ u_int tcp_autorcvbuf_inc = 16 * 1024;
static int pr_slowhz = PR_SLOWHZ;
const struct sysctl_bounded_args tcpctl_vars[] = {
- { TCPCTL_SLOWHZ, &pr_slowhz, 1, 0 },
+ { TCPCTL_SLOWHZ, &pr_slowhz, SYSCTL_INT_READONLY },
{ TCPCTL_RFC1323, &tcp_do_rfc1323, 0, 1 },
{ TCPCTL_KEEPINITTIME, &tcptv_keep_init, 1, 3 * TCPTV_KEEP_INIT },
{ TCPCTL_KEEPIDLE, &tcp_keepidle, 1, 5 * TCPTV_KEEP_IDLE },
Index: netinet6/ip6_input.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/netinet6/ip6_input.c,v
retrieving revision 1.232
diff -u -p -r1.232 ip6_input.c
--- netinet6/ip6_input.c 10 Mar 2021 10:21:49 -0000 1.232
+++ netinet6/ip6_input.c 27 Apr 2021 18:58:03 -0000
@@ -1339,9 +1339,9 @@ extern int ip6_mrtproto;
#endif
const struct sysctl_bounded_args ipv6ctl_vars[] = {
- { IPV6CTL_DAD_PENDING, &ip6_dad_pending, 1, 0 },
+ { IPV6CTL_DAD_PENDING, &ip6_dad_pending, SYSCTL_INT_READONLY },
#ifdef MROUTING
- { IPV6CTL_MRTPROTO, &ip6_mrtproto, 1, 0 },
+ { IPV6CTL_MRTPROTO, &ip6_mrtproto, SYSCTL_INT_READONLY },
#endif
{ IPV6CTL_FORWARDING, &ip6_forwarding, 0, 1 },
{ IPV6CTL_SENDREDIRECTS, &ip6_sendredirects, 0, 1 },
Index: sys/sysctl.h
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/sys/sysctl.h,v
retrieving revision 1.214
diff -u -p -r1.214 sysctl.h
--- sys/sysctl.h 10 Mar 2021 10:21:47 -0000 1.214
+++ sys/sysctl.h 27 Apr 2021 18:58:53 -0000
@@ -1000,6 +1000,9 @@ struct sysctl_bounded_args {
int maximum; /* read-only variable if minimum > maximum */
};
+#define SYSCTL_INT_UNBOUNDED 0,0
+#define SYSCTL_INT_READONLY 1,0
+
/*
* Internal sysctl function calling convention:
*
