git: 831c6b8edda6 - stable/13 - ipfilter: Support only jails in VNET

The branch stable/13 has been updated by cy:

URL: https://cgit.FreeBSD.org/src/commit/?id=831c6b8edda6c8d25db43e4d4bbf5120651bd1ec

commit 831c6b8edda6c8d25db43e4d4bbf5120651bd1ec
Author:     Cy Schubert <cy@FreeBSD.org>
AuthorDate: 2022-03-17 18:05:05 +0000
Commit:     Cy Schubert <cy@FreeBSD.org>
CommitDate: 2022-07-14 13:54:22 +0000

    ipfilter: Support only jails in VNET
    
    Jails without VNET have complete access to the ipfilter rules, NAT,
    pools and logs. This is insecure. Only allow jails to manipulate
    ipfilter rules, NAT tables and ippools if the jail has its own VNET.
    Otherwise a jail can affect the global system.
    
    This patch brings ipfilter in line with ipfw's support of VNET jails and
    non-support of non-VNET jails.
    
    (cherry picked from commit c47db49ba4aa7e74afe22591a62fbda95317932d)
---
 sbin/ipf/libipf/interror.c                    |  4 +++-
 sys/netpfil/ipfilter/netinet/ip_fil_freebsd.c |  7 +++++++
 sys/netpfil/ipfilter/netinet/ip_nat.c         |  9 +++++++++
 sys/netpfil/ipfilter/netinet/mlfk_ipl.c       | 12 ++++++++++++
 4 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/sbin/ipf/libipf/interror.c b/sbin/ipf/libipf/interror.c
index ca97254cb382..994fb9d2b320 100644
--- a/sbin/ipf/libipf/interror.c
+++ b/sbin/ipf/libipf/interror.c
@@ -17,7 +17,7 @@ typedef	struct	{
 
 static ipf_error_entry_t *find_error(int);
 
-#define	IPF_NUM_ERRORS	475
+#define	IPF_NUM_ERRORS	477
 
 /*
  * NO REUSE OF NUMBERS!
@@ -355,6 +355,7 @@ log" },
 	{	60073,	"unknown lookup group for next address (ipv6)" },
 	{	60074,	"unknown next address type (ipv6)" },
 	{	60075,	"one object at a time must be copied" },
+	{	60076,	"NAT ioctl denied in jail without VNET" },
 /* -------------------------------------------------------------------------- */
 	{	70001,	"incorrect object size to get pool stats" },
 	{	70002,	"could not malloc memory for new pool node" },
@@ -516,6 +517,7 @@ log" },
 	{	130015,	"ipf_init_all failed" },
 	{	130016,	"finding pfil head failed" },
 	{	130017,	"ipfilter is already initialised and running" },
+	{	130018,	"ioctl denied in jail without VNET" },
 };
 
 
diff --git a/sys/netpfil/ipfilter/netinet/ip_fil_freebsd.c b/sys/netpfil/ipfilter/netinet/ip_fil_freebsd.c
index f617584394cf..57a006ed5393 100644
--- a/sys/netpfil/ipfilter/netinet/ip_fil_freebsd.c
+++ b/sys/netpfil/ipfilter/netinet/ip_fil_freebsd.c
@@ -47,6 +47,7 @@ static const char rcsid[] = "@(#)$Id$";
 #include <net/route/nhop.h>
 #include <netinet/in.h>
 #include <netinet/in_fib.h>
+#include <netinet/in_pcb.h>
 #include <netinet/in_var.h>
 #include <netinet/in_systm.h>
 #include <netinet/ip.h>
@@ -281,6 +282,12 @@ ipfioctl(struct cdev *dev, ioctlcmd_t cmd, caddr_t data,
 		return (EPERM);
 	}
 
+	if (jailed_without_vnet(p->p_cred)) {
+		V_ipfmain.ipf_interror = 130018;
+		CURVNET_RESTORE();
+		return (EOPNOTSUPP);
+	}
+
 	unit = GET_MINOR(dev);
 	if ((IPL_LOGMAX < unit) || (unit < 0)) {
 		V_ipfmain.ipf_interror = 130002;
diff --git a/sys/netpfil/ipfilter/netinet/ip_nat.c b/sys/netpfil/ipfilter/netinet/ip_nat.c
index fd9429a623dd..9ee3082aa864 100644
--- a/sys/netpfil/ipfilter/netinet/ip_nat.c
+++ b/sys/netpfil/ipfilter/netinet/ip_nat.c
@@ -42,6 +42,9 @@ struct file;
 #include <sys/socket.h>
 #if defined(_KERNEL)
 # include <sys/systm.h>
+# if defined(__FreeBSD__)
+#  include <sys/jail.h>
+# endif
 # if !defined(__SVR4)
 #  include <sys/mbuf.h>
 # endif
@@ -999,6 +1002,12 @@ ipf_nat_ioctl(ipf_main_softc_t *softc, caddr_t data, ioctlcmd_t cmd,
 		IPFERROR(60001);
 		return (EPERM);
 	}
+# if defined(__FreeBSD__)
+	if (jailed_without_vnet(curthread->td_ucred)) {
+		IPFERROR(60076);
+		return (EOPNOTSUPP);
+	}
+# endif
 #endif
 
 	getlock = (mode & NAT_LOCKHELD) ? 0 : 1;
diff --git a/sys/netpfil/ipfilter/netinet/mlfk_ipl.c b/sys/netpfil/ipfilter/netinet/mlfk_ipl.c
index 872471bac38b..091d2c7d2061 100644
--- a/sys/netpfil/ipfilter/netinet/mlfk_ipl.c
+++ b/sys/netpfil/ipfilter/netinet/mlfk_ipl.c
@@ -377,6 +377,9 @@ sysctl_error:
 static int
 sysctl_ipf_int_nat ( SYSCTL_HANDLER_ARGS )
 {
+	if (jailed_without_vnet(curthread->td_ucred))
+		return (0);
+
 	ipf_nat_softc_t *nat_softc;
 
 	nat_softc = V_ipfmain.ipf_nat_soft;
@@ -388,6 +391,9 @@ sysctl_ipf_int_nat ( SYSCTL_HANDLER_ARGS )
 static int
 sysctl_ipf_int_state ( SYSCTL_HANDLER_ARGS )
 {
+	if (jailed_without_vnet(curthread->td_ucred))
+		return (0);
+
 	ipf_state_softc_t *state_softc;
 
 	state_softc = V_ipfmain.ipf_state_soft;
@@ -399,6 +405,9 @@ sysctl_ipf_int_state ( SYSCTL_HANDLER_ARGS )
 static int
 sysctl_ipf_int_auth ( SYSCTL_HANDLER_ARGS )
 {
+	if (jailed_without_vnet(curthread->td_ucred))
+		return (0);
+
 	ipf_auth_softc_t *auth_softc;
 
 	auth_softc = V_ipfmain.ipf_auth_soft;
@@ -410,6 +419,9 @@ sysctl_ipf_int_auth ( SYSCTL_HANDLER_ARGS )
 static int
 sysctl_ipf_int_frag ( SYSCTL_HANDLER_ARGS )
 {
+	if (jailed_without_vnet(curthread->td_ucred))
+		return (0);
+
 	ipf_frag_softc_t *frag_softc;
 
 	frag_softc = V_ipfmain.ipf_frag_soft;