Add sysctl variables for the Linuxulator. These reside under `compat.linux' as

discussed on current.

The following variables are defined (for now):

    osname (defaults to "Linux")
        Allow users to change the name of the OS as returned by uname(2),
        specially added for all those Linux Netscape users and statistics
        maniacs :-) We now have what we all wanted!

    osrelease (defaults to "2.2.5")
        Allow users to change the version of the OS as returned by uname(2).
        Since -current supports glibc2.1 now, change the default to 2.2.5
        (was 2.0.36).

    oss_version (defaults to 198144 [0x030600])
        This one will be used by the OSS_GETVERSION ioctl (PR 12917) which I
        can commit now that we have the MIB. The default version number is the
        lowest version possible with the current 'encoding'.

A note about imprisoned processes (see jail(2)):
  These variables are copy-on-write (as suggested by phk). This means that
  imprisoned processes will use the system wide value unless it is written/set
  by the process. From that moment on, a copy local to the prison will be
  used.

A note about the implementation:
  I choose to add a single pointer to struct prison, because I didn't like the
  idea of changing struct prison every time I come up with a new variable. As
  a side effect, the extra storage is only needed when a variable is set from
  within the prison. This also minimizes kernel bloat when the Linuxulator is
  not used; both compiled in or as a module.

Reviewed by: bde (first version only) and phk

3 files changed, 282 insertions, 3 deletions

diff --git a/sys/i386/linux/linux_mib.c b/sys/i386/linux/linux_mib.c
new file mode 100644
index 0000000..98b4a94f
--- /dev/null
+++ b/sys/i386/linux/linux_mib.c
@@ -0,0 +1,231 @@
+/*-
+ * Copyright (c) 1999 Marcel Moolenaar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer 
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software withough specific prior written permission
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *  $Id$
+ */
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+#include <sys/sysctl.h>
+#include <sys/proc.h>
+#include <sys/malloc.h>
+#include <sys/jail.h>
+
+#include <i386/linux/linux.h>
+#include <i386/linux/linux_mib.h>
+
+struct linux_prison {
+	char	pr_osname[LINUX_MAX_UTSNAME];
+	char	pr_osrelease[LINUX_MAX_UTSNAME];
+	int	pr_oss_version;
+};
+
+SYSCTL_NODE(_compat, OID_AUTO, linux, CTLFLAG_RW, 0,
+	    "Linux mode");
+
+static char	linux_osname[LINUX_MAX_UTSNAME] = "Linux";
+
+static int
+linux_sysctl_osname SYSCTL_HANDLER_ARGS
+{
+	char osname[LINUX_MAX_UTSNAME];
+	int error;
+
+	strcpy(osname, linux_get_osname(req->p));
+	error = sysctl_handle_string(oidp, osname, LINUX_MAX_UTSNAME, req);
+	if (error || req->newptr == NULL)
+		return (error);
+	error = linux_set_osname(req->p, osname);
+	return (error);
+}
+
+SYSCTL_PROC(_compat_linux, OID_AUTO, osname,
+	    CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON,
+	    0, 0, linux_sysctl_osname, "A",
+	    "Linux kernel OS name");
+
+static char	linux_osrelease[LINUX_MAX_UTSNAME] = "2.2.5";
+
+static int
+linux_sysctl_osrelease SYSCTL_HANDLER_ARGS
+{
+	char osrelease[LINUX_MAX_UTSNAME];
+	int error;
+
+	strcpy(osrelease, linux_get_osrelease(req->p));
+	error = sysctl_handle_string(oidp, osrelease, LINUX_MAX_UTSNAME, req);
+	if (error || req->newptr == NULL)
+		return (error);
+	error = linux_set_osrelease(req->p, osrelease);
+	return (error);
+}
+
+SYSCTL_PROC(_compat_linux, OID_AUTO, osrelease,
+	    CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_PRISON,
+	    0, 0, linux_sysctl_osrelease, "A",
+	    "Linux kernel OS release");
+
+static int	linux_oss_version = 0x030600;
+
+static int
+linux_sysctl_oss_version SYSCTL_HANDLER_ARGS
+{
+	int oss_version;
+	int error;
+
+	oss_version = linux_get_oss_version(req->p);
+	error = sysctl_handle_int(oidp, &oss_version, 0, req);
+	if (error || req->newptr == NULL)
+		return (error);
+	error = linux_set_oss_version(req->p, oss_version);
+	return (error);
+}
+
+SYSCTL_PROC(_compat_linux, OID_AUTO, oss_version,
+	    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_PRISON,
+	    0, 0, linux_sysctl_oss_version, "I",
+	    "Linux OSS version");
+
+static struct linux_prison *
+get_prison(struct proc *p)
+{
+	register struct prison *pr;
+	register struct linux_prison *lpr;
+
+	pr = p->p_prison;
+	if (pr == NULL)
+		return (NULL);
+
+	if (pr->pr_linux == NULL) {
+		MALLOC(lpr, struct linux_prison *, sizeof *lpr,
+		       M_PRISON, M_WAITOK);
+		bzero((caddr_t)lpr, sizeof *lpr);
+		pr->pr_linux = lpr;
+	}
+
+	return (pr->pr_linux);
+}
+
+char *
+linux_get_osname(p)
+	struct proc *p;
+{
+	register struct prison *pr;
+	register struct linux_prison *lpr;
+
+	pr = p->p_prison;
+	if (pr != NULL && pr->pr_linux != NULL) {
+		lpr = pr->pr_linux;
+		if (lpr->pr_osname[0])
+			return (lpr->pr_osname);
+	}
+
+	return (linux_osname);
+}
+
+int
+linux_set_osname(p, osname)
+	struct proc *p;
+	char *osname;
+{
+	register struct linux_prison *lpr;
+
+	lpr = get_prison(p);
+	if (lpr != NULL)
+		strcpy(lpr->pr_osname, osname);
+	else
+		strcpy(linux_osname, osname);
+
+	return (0);
+}
+
+char *
+linux_get_osrelease(p)
+	struct proc *p;
+{
+	register struct prison *pr;
+	register struct linux_prison *lpr;
+
+	pr = p->p_prison;
+	if (pr != NULL && pr->pr_linux != NULL) {
+		lpr = pr->pr_linux;
+		if (lpr->pr_osrelease[0])
+			return (lpr->pr_osrelease);
+	}
+
+	return (linux_osrelease);
+}
+
+int
+linux_set_osrelease(p, osrelease)
+	struct proc *p;
+	char *osrelease;
+{
+	register struct linux_prison *lpr;
+
+	lpr = get_prison(p);
+	if (lpr != NULL)
+		strcpy(lpr->pr_osrelease, osrelease);
+	else
+		strcpy(linux_osrelease, osrelease);
+
+	return (0);
+}
+
+int
+linux_get_oss_version(p)
+	struct proc *p;
+{
+	register struct prison *pr;
+	register struct linux_prison *lpr;
+
+	pr = p->p_prison;
+	if (pr != NULL && pr->pr_linux != NULL) {
+		lpr = pr->pr_linux;
+		if (lpr->pr_oss_version)
+			return (lpr->pr_oss_version);
+	}
+
+	return (linux_oss_version);
+}
+
+int
+linux_set_oss_version(p, oss_version)
+	struct proc *p;
+	int oss_version;
+{
+	register struct linux_prison *lpr;
+
+	lpr = get_prison(p);
+	if (lpr != NULL)
+		lpr->pr_oss_version = oss_version;
+	else
+		linux_oss_version = oss_version;
+
+	return (0);
+}
diff --git a/sys/i386/linux/linux_mib.h b/sys/i386/linux/linux_mib.h
new file mode 100644
index 0000000..24c2548
--- /dev/null
+++ b/sys/i386/linux/linux_mib.h
@@ -0,0 +1,43 @@
+/*-
+ * Copyright (c) 1999 Marcel Moolenaar
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer 
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software withough specific prior written permission
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ *  $Id$
+ */
+
+#ifndef _LINUX_MIB_H_
+#define _LINUX_MIB_H_
+
+char*	linux_get_osname	__P((struct proc *p));
+int	linux_set_osname	__P((struct proc *p, char *osname));
+
+char*	linux_get_osrelease	__P((struct proc *p));
+int	linux_set_osrelease	__P((struct proc *p, char *osrelease));
+
+int	linux_get_oss_version	__P((struct proc *p));
+int	linux_set_oss_version	__P((struct proc *p, int oss_version));
+
+#endif /* _LINUX_MIB_H_ */
diff --git a/sys/i386/linux/linux_misc.c b/sys/i386/linux/linux_misc.c
index 929bfaa..74fb731 100644
--- a/sys/i386/linux/linux_misc.c
+++ b/sys/i386/linux/linux_misc.c
@@ -25,7 +25,7 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
- *  $Id: linux_misc.c,v 1.66 1999/08/25 11:19:02 marcel Exp $
+ *  $Id: linux_misc.c,v 1.67 1999/08/25 14:11:01 marcel Exp $
  */
 
 #include "opt_compat.h"
@@ -61,6 +61,7 @@
 #include <i386/linux/linux.h>
 #include <i386/linux/linux_proto.h>
 #include <i386/linux/linux_util.h>
+#include <i386/linux/linux_mib.h>
 
 #include <posix4/sched.h>
 
@@ -880,15 +881,19 @@ int
 linux_newuname(struct proc *p, struct linux_newuname_args *args)
 {
 	struct linux_new_utsname utsname;
+	char *osrelease, *osname;
 
 #ifdef DEBUG
 	printf("Linux-emul(%ld): newuname(*)\n", (long)p->p_pid);
 #endif
 
+	osname = linux_get_osname(p);
+	osrelease = linux_get_osrelease(p);
+
 	bzero(&utsname, sizeof(struct linux_new_utsname));
-	strncpy(utsname.sysname, "Linux", LINUX_MAX_UTSNAME-1);
+	strncpy(utsname.sysname, osname, LINUX_MAX_UTSNAME-1);
 	strncpy(utsname.nodename, hostname, LINUX_MAX_UTSNAME-1);
-	strncpy(utsname.release, "2.0.36", LINUX_MAX_UTSNAME-1);
+	strncpy(utsname.release, osrelease, LINUX_MAX_UTSNAME-1);
 	strncpy(utsname.version, version, LINUX_MAX_UTSNAME-1);
 	strncpy(utsname.machine, machine, LINUX_MAX_UTSNAME-1);
 	strncpy(utsname.domainname, domainname, LINUX_MAX_UTSNAME-1);