Re: KERNEL PATCH: add process hiding (fixed)
Thanks, Michael. Leave it to me to forget to update the documentation..
Here's the patch with the manpage change:
Index: sys/kern/kern_sysctl.c
===
RCS file: /cvs/src/sys/kern/kern_sysctl.c,v
retrieving revision 1.320
diff -u -p -u -r1.320 kern_sysctl.c
--- sys/kern/kern_sysctl.c 11 Nov 2016 18:59:09 - 1.320
+++ sys/kern/kern_sysctl.c 4 Dec 2016 20:43:53 -
@@ -263,6 +263,7 @@ size_t disknameslen;
struct diskstats *diskstats = NULL;
size_t diskstatslen;
int securelevel;
+int seeotheruids = 1; /* on by default */
/*
* kernel related system variables.
@@ -632,6 +633,13 @@ kern_sysctl(int *name, u_int namelen, vo
dnsjackport = port;
return 0;
}
+ case KERN_SEEOTHERUIDS: {
+ if (securelevel > 0)
+ return (sysctl_rdint(oldp, oldlenp, newp,
+ seeotheruids));
+ return (sysctl_int(oldp, oldlenp, newp, newlen,
+ ));
+ }
default:
return (EOPNOTSUPP);
}
@@ -1427,7 +1435,8 @@ sysctl_doproc(int *name, u_int namelen,
int arg, buflen, doingzomb, elem_size, elem_count;
int error, needed, op;
int dothreads = 0;
- int show_pointers;
+ int is_suser, show_pointers, show_otheruids;
+ uid_t euid;
dp = where;
buflen = where != NULL ? *sizep : 0;
@@ -1444,7 +1453,10 @@ sysctl_doproc(int *name, u_int namelen,
dothreads = op & KERN_PROC_SHOW_THREADS;
op &= ~KERN_PROC_SHOW_THREADS;
- show_pointers = suser(curproc, 0) == 0;
+ is_suser = suser(curproc, 0) == 0;
+ show_pointers = is_suser;
+ show_otheruids = seeotheruids || is_suser;
+ euid = curproc->p_ucred->cr_uid;
if (where != NULL)
kproc = malloc(sizeof(*kproc), M_TEMP, M_WAITOK);
@@ -1461,6 +1473,9 @@ again:
* Skip embryonic processes.
*/
if (pr->ps_flags & PS_EMBRYO)
+ continue;
+
+ if (!show_otheruids && pr->ps_ucred->cr_uid != euid)
continue;
/*
Index: sys/sys/sysctl.h
===
RCS file: /cvs/src/sys/sys/sysctl.h,v
retrieving revision 1.170
diff -u -p -u -r1.170 sysctl.h
--- sys/sys/sysctl.h7 Nov 2016 00:26:32 - 1.170
+++ sys/sys/sysctl.h4 Dec 2016 20:43:55 -
@@ -184,7 +184,8 @@ struct ctlname {
#defineKERN_GLOBAL_PTRACE 81 /* allow ptrace globally */
#defineKERN_CONSBUFSIZE82 /* int: console message buffer
size */
#defineKERN_CONSBUF83 /* console message buffer */
-#defineKERN_MAXID 84 /* number of valid kern ids */
+#defineKERN_SEEOTHERUIDS 84 /* see other users' proceesses
*/
+#defineKERN_MAXID 85 /* number of valid kern ids */
#defineCTL_KERN_NAMES { \
{ 0, 0 }, \
@@ -269,6 +270,9 @@ struct ctlname {
{ "proc_nobroadcastkill", CTLTYPE_NODE }, \
{ "proc_vmmap", CTLTYPE_NODE }, \
{ "global_ptrace", CTLTYPE_INT }, \
+ { "gap", 0 }, \
+ { "gap", 0 }, \
+ { "see_other_uids", CTLTYPE_INT }, \
}
/*
Index: sbin/sysctl/sysctl.8
===
RCS file: /cvs/src/sbin/sysctl/sysctl.8,v
retrieving revision 1.208
diff -u -p -u -r1.208 sysctl.8
--- sbin/sysctl/sysctl.815 Oct 2016 14:43:53 - 1.208
+++ sbin/sysctl/sysctl.85 Dec 2016 02:04:52 -
@@ -194,6 +194,7 @@ and a few require a kernel compiled with
.It kern.wxabort Ta integer Ta yes
.It kern.consdev Ta string Ta no
.It kern.global_ptrace Ta integer Ta yes
+.It kern.see_other_uids Ta integer Ta yes
.It vm.vmmeter Ta struct Ta no
.It vm.loadavg Ta struct Ta no
.It vm.psstrings Ta struct Ta no
On Mon, Dec 05, 2016 at 08:55:19AM +0800, Michael W. Bombardieri wrote:
> Should this patch also add see_other_uids in sysctl(8) manual?
>
> On Sun, Dec 04, 2016 at 07:49:12PM -0500, Ian Walker wrote:
> > (( Resending my last from a client that (hopefully) won't mangle the email.
> >Sorry about the noise, folks. ))
> >
> >
> > Hello OpenBSD Community -
> >
> > OpenBSD should have the ability to prevent users from seeing each other's
> > processes even if this ability is disabled by default.
> > In addition to the small security benefit this provides, it also affords
> > each user a much greater amount of privacy. Linux and
> > FreeBSD already support similar features (
> > https://www.cyberciti.biz/faq/linux-hide-processes-from-other-users/ &&
> > https://www.cyberciti.biz/faq/freebsd-disable-ps-sockstat-command-information-leakage/
> > ) and the implementation itself is fairly
> > trivial.
> >
> > Below is a patch which implements
Re: KERNEL PATCH: add process hiding (fixed)
Should this patch also add see_other_uids in sysctl(8) manual?
On Sun, Dec 04, 2016 at 07:49:12PM -0500, Ian Walker wrote:
> (( Resending my last from a client that (hopefully) won't mangle the email.
>Sorry about the noise, folks. ))
>
>
> Hello OpenBSD Community -
>
> OpenBSD should have the ability to prevent users from seeing each other's
> processes even if this ability is disabled by default.
> In addition to the small security benefit this provides, it also affords each
> user a much greater amount of privacy. Linux and
> FreeBSD already support similar features (
> https://www.cyberciti.biz/faq/linux-hide-processes-from-other-users/ &&
> https://www.cyberciti.biz/faq/freebsd-disable-ps-sockstat-command-information-leakage/
> ) and the implementation itself is fairly
> trivial.
>
> Below is a patch which implements basic process hiding for non-superusers and
> is activated with a sysctl knob. Similar to that of
> FreeBSD it is called "kern.see_other_uids??. The idea is that if process
> spying is a security or privacy concern for you, you
> would add "kern.see_other_uids=0" to sysctl.conf and reboot (assuming
> securelevel > 0).
>
> I look forward to your comments.
>
> Thanks and cheers all -
> Ian Walker
>
>
>
> Index: sys/kern/kern_sysctl.c
> ===
> RCS file: /cvs/src/sys/kern/kern_sysctl.c,v
> retrieving revision 1.320
> diff -u -p -u -r1.320 kern_sysctl.c
> --- sys/kern/kern_sysctl.c11 Nov 2016 18:59:09 -1.320
> +++ sys/kern/kern_sysctl.c4 Dec 2016 20:43:53 -
> @@ -263,6 +263,7 @@ size_t disknameslen;
> struct diskstats *diskstats = NULL;
> size_t diskstatslen;
> int securelevel;
> +int seeotheruids = 1; /* on by default */
>
> /*
> * kernel related system variables.
> @@ -632,6 +633,13 @@ kern_sysctl(int *name, u_int namelen, vo
> dnsjackport = port;
> return 0;
> }
> +case KERN_SEEOTHERUIDS: {
> +if (securelevel > 0)
> +return (sysctl_rdint(oldp, oldlenp, newp,
> +seeotheruids));
> +return (sysctl_int(oldp, oldlenp, newp, newlen,
> +));
> +}
> default:
> return (EOPNOTSUPP);
> }
> @@ -1427,7 +1435,8 @@ sysctl_doproc(int *name, u_int namelen,
> int arg, buflen, doingzomb, elem_size, elem_count;
> int error, needed, op;
> int dothreads = 0;
> -int show_pointers;
> +int is_suser, show_pointers, show_otheruids;
> +uid_t euid;
>
> dp = where;
> buflen = where != NULL ? *sizep : 0;
> @@ -1444,7 +1453,10 @@ sysctl_doproc(int *name, u_int namelen,
> dothreads = op & KERN_PROC_SHOW_THREADS;
> op &= ~KERN_PROC_SHOW_THREADS;
>
> -show_pointers = suser(curproc, 0) == 0;
> +is_suser = suser(curproc, 0) == 0;
> +show_pointers = is_suser;
> +show_otheruids = seeotheruids || is_suser;
> +euid = curproc->p_ucred->cr_uid;
>
> if (where != NULL)
> kproc = malloc(sizeof(*kproc), M_TEMP, M_WAITOK);
> @@ -1461,6 +1473,9 @@ again:
> * Skip embryonic processes.
> */
> if (pr->ps_flags & PS_EMBRYO)
> +continue;
> +
> +if (!show_otheruids && pr->ps_ucred->cr_uid != euid)
> continue;
>
> /*
> Index: sys/sys/sysctl.h
> ===
> RCS file: /cvs/src/sys/sys/sysctl.h,v
> retrieving revision 1.170
> diff -u -p -u -r1.170 sysctl.h
> --- sys/sys/sysctl.h7 Nov 2016 00:26:32 -1.170
> +++ sys/sys/sysctl.h4 Dec 2016 20:43:55 -
> @@ -184,7 +184,8 @@ struct ctlname {
> #defineKERN_GLOBAL_PTRACE81/* allow ptrace globally */
> #defineKERN_CONSBUFSIZE82/* int: console message buffer size */
> #defineKERN_CONSBUF83/* console message buffer */
> -#defineKERN_MAXID84/* number of valid kern ids */
> +#defineKERN_SEEOTHERUIDS84/* see other users' proceesses */
> +#defineKERN_MAXID85/* number of valid kern ids */
>
> #defineCTL_KERN_NAMES { \
> { 0, 0 }, \
> @@ -269,6 +270,9 @@ struct ctlname {
> { "proc_nobroadcastkill", CTLTYPE_NODE }, \
> { "proc_vmmap", CTLTYPE_NODE }, \
> { "global_ptrace", CTLTYPE_INT }, \
> +{ "gap", 0 }, \
> +{ "gap", 0 }, \
> +{ "see_other_uids", CTLTYPE_INT }, \
> }
>
> /*
>
KERNEL PATCH: add process hiding (fixed)
(( Resending my last from a client that (hopefully) won't mangle the email.
Sorry about the noise, folks. ))
Hello OpenBSD Community -
OpenBSD should have the ability to prevent users from seeing each other's
processes even if this ability is disabled by default.
In addition to the small security benefit this provides, it also affords each
user a much greater amount of privacy. Linux and
FreeBSD already support similar features (
https://www.cyberciti.biz/faq/linux-hide-processes-from-other-users/ &&
https://www.cyberciti.biz/faq/freebsd-disable-ps-sockstat-command-information-leakage/
) and the implementation itself is fairly
trivial.
Below is a patch which implements basic process hiding for non-superusers and
is activated with a sysctl knob. Similar to that of
FreeBSD it is called "kern.see_other_uids¨. The idea is that if process spying
is a security or privacy concern for you, you
would add "kern.see_other_uids=0" to sysctl.conf and reboot (assuming
securelevel > 0).
I look forward to your comments.
Thanks and cheers all -
Ian Walker
Index: sys/kern/kern_sysctl.c
===
RCS file: /cvs/src/sys/kern/kern_sysctl.c,v
retrieving revision 1.320
diff -u -p -u -r1.320 kern_sysctl.c
--- sys/kern/kern_sysctl.c11 Nov 2016 18:59:09 -1.320
+++ sys/kern/kern_sysctl.c4 Dec 2016 20:43:53 -
@@ -263,6 +263,7 @@ size_t disknameslen;
struct diskstats *diskstats = NULL;
size_t diskstatslen;
int securelevel;
+int seeotheruids = 1; /* on by default */
/*
* kernel related system variables.
@@ -632,6 +633,13 @@ kern_sysctl(int *name, u_int namelen, vo
dnsjackport = port;
return 0;
}
+case KERN_SEEOTHERUIDS: {
+if (securelevel > 0)
+return (sysctl_rdint(oldp, oldlenp, newp,
+seeotheruids));
+return (sysctl_int(oldp, oldlenp, newp, newlen,
+));
+}
default:
return (EOPNOTSUPP);
}
@@ -1427,7 +1435,8 @@ sysctl_doproc(int *name, u_int namelen,
int arg, buflen, doingzomb, elem_size, elem_count;
int error, needed, op;
int dothreads = 0;
-int show_pointers;
+int is_suser, show_pointers, show_otheruids;
+uid_t euid;
dp = where;
buflen = where != NULL ? *sizep : 0;
@@ -1444,7 +1453,10 @@ sysctl_doproc(int *name, u_int namelen,
dothreads = op & KERN_PROC_SHOW_THREADS;
op &= ~KERN_PROC_SHOW_THREADS;
-show_pointers = suser(curproc, 0) == 0;
+is_suser = suser(curproc, 0) == 0;
+show_pointers = is_suser;
+show_otheruids = seeotheruids || is_suser;
+euid = curproc->p_ucred->cr_uid;
if (where != NULL)
kproc = malloc(sizeof(*kproc), M_TEMP, M_WAITOK);
@@ -1461,6 +1473,9 @@ again:
* Skip embryonic processes.
*/
if (pr->ps_flags & PS_EMBRYO)
+continue;
+
+if (!show_otheruids && pr->ps_ucred->cr_uid != euid)
continue;
/*
Index: sys/sys/sysctl.h
===
RCS file: /cvs/src/sys/sys/sysctl.h,v
retrieving revision 1.170
diff -u -p -u -r1.170 sysctl.h
--- sys/sys/sysctl.h7 Nov 2016 00:26:32 -1.170
+++ sys/sys/sysctl.h4 Dec 2016 20:43:55 -
@@ -184,7 +184,8 @@ struct ctlname {
#defineKERN_GLOBAL_PTRACE81/* allow ptrace globally */
#defineKERN_CONSBUFSIZE82/* int: console message buffer size */
#defineKERN_CONSBUF83/* console message buffer */
-#defineKERN_MAXID84/* number of valid kern ids */
+#defineKERN_SEEOTHERUIDS84/* see other users' proceesses */
+#defineKERN_MAXID85/* number of valid kern ids */
#defineCTL_KERN_NAMES { \
{ 0, 0 }, \
@@ -269,6 +270,9 @@ struct ctlname {
{ "proc_nobroadcastkill", CTLTYPE_NODE }, \
{ "proc_vmmap", CTLTYPE_NODE }, \
{ "global_ptrace", CTLTYPE_INT }, \
+{ "gap", 0 }, \
+{ "gap", 0 }, \
+{ "see_other_uids", CTLTYPE_INT }, \
}
/*
