security.jail.allow_raw_sockets sysctl MIB is set to 1) where privileged
access to jails is given out, it is possible for prison root to manipulate
various network parameters which effect the host environment. This commit
plugs a number of security holes associated with the use of raw sockets
and prisons.
This commit makes the following changes:
- Add a comment to rtioctl warning developers that if they add
any ioctl commands, they should use super-user checks where necessary,
as it is possible for PRISON root to make it this far in execution.
- Add super-user checks for the execution of the SIOCGETVIFCNT
and SIOCGETSGCNT IP multicast ioctl commands.
- Add a super-user check to rip_ctloutput(). If the calling cred
is PRISON root, make sure the socket option name is IP_HDRINCL,
otherwise deny the request.
Although this patch corrects a number of security problems associated
with raw sockets and prisons, the warning in jail(8) should still
apply, and by default we should keep the default value of
security.jail.allow_raw_sockets MIB to 0 (or disabled) until
we are certain that we have tracked down all the problems.
Looking forward, we will probably want to eliminate the
references to curthread.
This may be a MFC candidate for RELENG_5.
Reviewed by: rwatson
Approved by: bmilekic (mentor)
called "rtentry".
This saves a considerable amount of kernel memory. R_Zmalloc previously
used 256 byte blocks (plus kmalloc overhead) whereas UMA only needs 132
bytes.
Idea from: OpenBSD
it checked for rt == NULL after dereferencing the pointer).
We never check for those events elsewhere, so probably these checks
might go away here as well.
Slightly simplify (and document) the logic for memory allocation
in rt_setgate().
The rest is mostly style changes -- replace 0 with NULL where appropriate,
remove the macro SA() that was only used once, remove some useless
debugging code in rt_fixchange, explain some odd-looking casts.
of an interface. No functional change.
On passing, comment a likely bug in net/rtsock.c:sysctl_ifmalist()
which, if confirmed, would deserve to be fixed and MFC'ed
the space occupied by a struct sockaddr when passed through a
routing socket.
Use it to replace the macro ROUNDUP(int), that does the same but
is redefined by every file which uses it, courtesy of
the School of Cut'n'Paste Programming(TM).
(partial) userland changes to follow.
accordingly. The define is left intact for ABI compatibility
with userland.
This is a pre-step for the introduction of tcp_hostcache. The
network stack remains fully useable with this change.
Reviewed by: sam (mentor), bms
Reviewed by: -net, -current, core@kame.net (IPv6 parts)
Approved by: re (scottl)
routine that takes a locked routing table reference and removes all
references to the entry in the various data structures. This
eliminates instances of recursive locking and also closes races
where the lock on the entry had to be dropped prior to calling
rtrequest(RTM_DELETE). This also cleans up confusion where the
caller held a reference to an entry that might have been reclaimed
(and in some cases used that reference).
Supported by: FreeBSD Foundation
that covers updates to the contents. Note this is separate from holding
a reference and/or locking the routing table itself.
Other/related changes:
o rtredirect loses the final parameter by which an rtentry reference
may be returned; this was never used and added unwarranted complexity
for locking.
o minor style cleanups to routing code (e.g. ansi-fy function decls)
o remove the logic to bump the refcnt on the parent of cloned routes,
we assume the parent will remain as long as the clone; doing this avoids
a circularity in locking during delete
o convert some timeouts to MPSAFE callouts
Notes:
1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level
applications cannot/do-no know about mutex's. Doing this requires
that the mutex be the last element in the structure. A better solution
is to introduce an externalized version of struct rtentry but this is
a major task because of the intertwining of rtentry and other data
structures that are visible to user applications.
2. There are known LOR's that are expected to go away with forthcoming
work to eliminate many held references. If not these will be resolved
prior to release.
3. ATM changes are untested.
Sponsored by: FreeBSD Foundation
Obtained from: BSD/OS (partly)
o move route_cb to be private to rtsock.c
o replace global static route_proto by locals
o eliminate global #define shorthands for info references
o remove some register decls
o ansi-fy function decls
o move items to be close in scope to their usage
o add rt_dispatch function for dispatching the actual message
o cleanup tangled logic for doing all-but-me msg send
Support by: FreeBSD Foundation
when julian@ added it, but the commented out code had at least
one bug -- not freeing the allocated mbuf.
Anyway, this comment no longer applies as of revision 1.67, so
remove it.
the entry being removed (ret_nrt != NULL), increment the entry's
rt_refcnt like we do it for RTM_ADD and RTM_RESOLVE, rather than
messing around with 1->0 transitions for rtfree() all over.
to current leaves because function may vanish the current node.
If parent RTA_GENMASK route has a clone (a "cloning clone"), an
rn_walktree_from() starting from parent will cause another walk
starting from clone. If a function is either rt_fixdelete() or
rt_fixchange(), this recursive walk may vanish the leaf that is
remembered by an outer walk (the "next leaf" above), panicing a
system when it resumes with an outer walk.
The following script paniced my single-user mode booted system:
: sysctl net.inet.ip.forwarding=1
: ipfw add 1 allow ip from any to any
: ifconfig lo0 127.1
: route add -net 10 -genmask 255.255.255.0 127.1
: telnet 10.1 # rt_fixchange() panic
: telnet 10.2
: telnet 10.1
: route delete -net 10 # rt_fixdelete() panic
For the time being, avoid these races by disallowing recursive
walks in rt_fixchange() and rt_fixdelete().
Also, make a slight optimization in the rtrequest(RTM_RESOLVE)
case: there is no reason to call rt_fixchange() in this case.
PR: kern/37606
MFC after: 5 days
No functional changes, but:
+ the mrouting module now should behave the same as the compiled-in
version (it did not before, some of the rsvp code was not loaded
properly);
+ netinet/ip_mroute.c is now truly optional;
+ removed some redundant/unused code;
+ changed many instances of '0' to NULL and INADDR_ANY as appropriate;
+ removed several static variables to make the code more SMP-friendly;
+ fixed some minor bugs in the mrouting code (mostly, incorrect return
values from functions).
This commit is also a prerequisite to the addition of support for PIM,
which i would like to put in before DP2 (it does not change any of
the existing APIs, anyways).
Note, in the process we found out that some device drivers fail to
properly handle changes in IFF_ALLMULTI, leading to interesting
behaviour when a multicast router is started. This bug is not
corrected by this commit, and will be fixed with a separate commit.
Detailed changes:
--------------------
netinet/ip_mroute.c all the above.
conf/files make ip_mroute.c optional
net/route.c fix mrt_ioctl hook
netinet/ip_input.c fix ip_mforward hook, move rsvp_input() here
together with other rsvp code, and a couple
of indentation fixes.
netinet/ip_output.c fix ip_mforward and ip_mcast_src hooks
netinet/ip_var.h rsvp function hooks
netinet/raw_ip.c hooks for mrouting and rsvp functions, plus
interface cleanup.
netinet/ip_mroute.h remove an unused and optional field from a struct
Most of the code is from Pavlin Radoslavov and the XORP project
Reviewed by: sam
MFC after: 1 week
a route is cloned. Previously, they took on the count
of their parent route (which was sometimes nonzero.)
Submitted by: Andre Oppermann <oppermann@pipeline.ch>
MFC after: 5 days
Have sys/net/route.c:rtrequest1(), which takes ``rt_addrinfo *''
as the argument. Pass rt_addrinfo all the way down to rtrequest1
and ifa->ifa_rtrequest. 3rd argument of ifa->ifa_rtrequest is now
``rt_addrinfo *'' instead of ``sockaddr *'' (almost noone is
using it anyways).
Benefit: the following command now works. Previously we needed
two route(8) invocations, "add" then "change".
# route add -inet6 default ::1 -ifp gif0
Remove unsafe typecast in rtrequest(), from ``rtentry *'' to
``sockaddr *''. It was introduced by 4.3BSD-Reno and never
corrected.
Obtained from: BSD/OS, NetBSD
MFC after: 1 month
PR: kern/28360
effect, which would cause unnecessary route deletion:
* Unfortunately, this has the obnoxious
* property of also triggering for insertion /above/ a pre-existing network
* route and clones. Sigh. This may be fixed some day.
The effect has been even worse, because recent versions of route.c set
the parent rtentry for cloned routes from an interface-direct route.
For example, suppose that we have an interface "ne0" that has an IPv4
subnet "10.0.0.0/24". Then we may have a cloned route like 10.0.0.1
on the interface, whose parent route is 10.0.0.0/24 (to the interface
ne0). Now, when we add the default route (i.e. 0.0.0.0/0),
rt_fixchange() will remove the cloned route 10.0.0.1. The (bad) effect
also prevents rt_setgate from configuring rt_gwroute, which would not
be an intended behavior.
As suggested in the comments to rt_fixchange(), we need stricter check
in the function, to prevent unintentional route deletion.
This fix also solve the "IPV6 panic?" problem in nd6_timer().
Submitted by: JINMEI Tatuya <jinmei@isl.rdc.toshiba.co.jp>
MFC after: 4 days
route in ifa_ifwithroute(), as the last resort, look up the route to
the gateway, not destination (to derive the interface from).
PR: kern/27852
Submitted by: Iasen Kostoff <tbyte@tbyte.org>
MFC after: 2 weeks
A route generated from an RTF_CLONING route had the RTF_WASCLONED flag
set but did not have a reference to the parent route, as documented in
the rtentry(9) manpage. This prevented such routes from being deleted
when their parent route is deleted.
Now, for example, if you delete an IP address from a network interface,
all ARP entries that were cloned from this interface route are flushed.
This also has an impact on netstat(1) output. Previously, dynamically
created ARP cache entries (RTF_STATIC flag is unset) were displayed as
part of the routing table display (-r). Now, they are only printed if
the -a option is given.
netinet/in.c, netinet/in_rmx.c:
When address is removed from an interface, also delete all routes that
point to this interface and address. Previously, for example, if you
changed the address on an interface, outgoing IP datagrams might still
use the old address. The only solution was to delete and re-add some
routes. (The problem is easily observed with the route(8) command.)
Note, that if the socket was already bound to the local address before
this address is removed, new datagrams generated from this socket will
still be sent from the old address.
PR: kern/20785, kern/21914
Reviewed by: wollman (the idea)
search routine, and scratching our heads over why it was so obfuscated.
This delta fixes a number of confusing style bugs and renames several
structure members to have more meaningful names. There remain a number
of odd control-flow structures. These changes do not affect the generated
code.
Pleases let me make sure that no one touch the invalid ro_rt pointer,
after splx(s) and before next ro_rt initialization.
Though usually this seems to be already called at splnet,
I still sometime experience kernel crash at rtfree() in my
INET6 enabled environment where IPv6 connection is frequently used.
(Off-course, it might be just due to another bug.)
