Hannes Frederic Sowa
482fc6094a
ipv4: introduce new IP_MTU_DISCOVER mode IP_PMTUDISC_INTERFACE ...
Sockets marked with IP_PMTUDISC_INTERFACE won't do path mtu discovery,
their sockets won't accept and install new path mtu information and they
will always use the interface mtu for outgoing packets. It is guaranteed
that the packet is not fragmented locally. But we won't set the DF-Flag
on the outgoing frames.
Florian Weimer had the idea to use this flag to ensure DNS servers are
never generating outgoing fragments. They may well be fragmented on the
path, but the server never stores or usees path mtu values, which could
well be forged in an attack.
(The root of the problem with path MTU discovery is that there is
no reliable way to authenticate ICMP Fragmentation Needed But DF Set
messages because they are sent from intermediate routers with their
source addresses, and the IMCP payload will not always contain sufficient
information to identify a flow.)
Recent research in the DNS community showed that it is possible to
implement an attack where DNS cache poisoning is feasible by spoofing
fragments. This work was done by Amir Herzberg and Haya Shulman:
<https://sites.google.com/site/hayashulman/files/fragmentation-poisoning.pdf >
This issue was previously discussed among the DNS community, e.g.
<http://www.ietf.org/mail-archive/web/dnsext/current/msg01204.html >,
without leading to fixes.
This patch depends on the patch "ipv4: fix DO and PROBE pmtu mode
regarding local fragmentation with UFO/CORK" for the enforcement of the
non-fragmentable checks. If other users than ip_append_page/data should
use this semantic too, we have to add a new flag to IPCB(skb)->flags to
suppress local fragmentation and check for this in ip_finish_output.
Many thanks to Florian Weimer for the idea and feedback while implementing
this patch.
Cc: David S. Miller <davem@davemloft.net>
Suggested-by: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-05 21:52:27 -05:00
for-linus-3.12-merge minor 9p fixes and tweaks for 3.12 merge window
2013-09-11 12:34:13 -07:00
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem
2013-11-04 14:51:28 -05:00
caif_hsi.h: Remove extern from function prototypes
2013-09-23 16:29:41 -04:00
irda: update comment mentioning IRQF_DISABLED
2013-10-17 15:13:20 -04:00
af_iucv: fix recvmsg by replacing skb_pull() function
2013-04-08 17:16:57 -04:00
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
2013-11-04 19:46:58 -05:00
tcp_memcontrol: Remove the per netns control.
2013-10-21 18:43:02 -04:00
NFC: NCI: Modify NCI SPI to implement CS/INT handshake per the spec
2013-09-25 14:59:56 +02:00
net: sctp: fix and consolidate SCTP checksumming code
2013-11-03 23:04:57 -05:00
net: Remove extern from include/net/ scheduling prototypes
2013-07-31 17:24:22 -07:00
IPv6 NAT: Do not drop DNATed 6to4/6rd packets
2013-09-28 15:56:15 -04:00
af_rxrpc.h: Remove extern from function prototypes
2013-07-31 17:50:01 -07:00
af_unix: improve STREAM behavior with fragmented memory
2013-08-10 01:16:44 -07:00
VSOCK: Move af_vsock.h and vsock_addr.h to include/net
2013-07-27 22:14:06 -07:00
arp/neighbour.h: Remove extern from function prototypes
2013-07-31 17:50:02 -07:00
ax25.h: Remove extern from function prototypes
2013-07-31 17:50:02 -07:00
net: add cpu_relax to busy poll loop
2013-08-28 17:45:48 -04:00
cfg80211: export reg_initiator_name()
2013-10-18 14:04:40 -04:00
net: checksum: fix warning in skb_checksum
2013-11-04 15:27:08 -05:00
net: fix cipso packet validation when !NETLABEL
2013-10-19 18:55:42 -04:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2013-09-05 14:54:29 -07:00
net: codel: Avoid undefined behavior from signed overflow
2013-11-04 20:01:29 -05:00
compat.h: Remove extern from function prototypes
2013-09-20 14:49:32 -04:00
dcbevent.h: Remove extern from function prototypes
2013-09-20 14:49:32 -04:00
decnet (dn*.h): Remove extern from function prototypes
2013-09-20 14:49:32 -04:00
decnet (dn*.h): Remove extern from function prototypes
2013-09-20 14:49:32 -04:00
decnet (dn*.h): Remove extern from function prototypes
2013-09-20 14:49:32 -04:00
decnet (dn*.h): Remove extern from function prototypes
2013-09-20 14:49:32 -04:00
decnet (dn*.h): Remove extern from function prototypes
2013-09-20 14:49:32 -04:00
decnet (dn*.h): Remove extern from function prototypes
2013-09-20 14:49:32 -04:00
ipv6: Optimize ipv6_change_dsfield().
2013-01-09 23:59:53 -08:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
2013-10-23 16:49:34 -04:00
net: esp{4,6}: get rid of struct esp_data
2013-10-29 06:39:42 +01:00
fib_rules.h: Remove extern from function prototypes
2013-09-20 14:49:33 -04:00
firewire net, ipv4 arp: Extend hardware address and remove driver-level packet inspection.
2013-03-26 12:32:13 -04:00
flow.h/flow_keys.h: Remove extern from function prototypes
2013-09-20 14:49:33 -04:00
flow_dissector: factor out the ports extraction in skb_flow_get_ports
2013-10-03 15:36:37 -04:00
garp.h: Remove extern from function prototypes
2013-09-20 14:49:33 -04:00
gen_stats.h: Remove extern from function prototypes
2013-09-20 14:49:33 -04:00
genetlink.h: Remove extern from function prototypes
2013-09-20 14:49:33 -04:00
ipv4: generalize gre_handle_offloads
2013-10-19 19:36:18 -04:00
gro: Fix kcalloc argument order
2013-01-27 22:46:33 -05:00
icmp.h: Remove extern from function prototypes
2013-09-20 14:49:33 -04:00
mac80211: add radiotap flag and handling for 5/10 MHz
2013-07-16 09:58:05 +03:00
ieee802154/nl-mac.c: make some MLME operations optional
2013-04-08 12:00:16 -04:00
ipv6: Remove privacy config option.
2013-10-28 20:07:50 -04:00
inet*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
ipv6: split inet6_ehashfn to hash functions per compilation unit
2013-10-19 19:45:34 -04:00
inet*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
inet*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
net: Correct comparisons and calculations using skb->tail and skb-transport_header
2013-05-28 23:49:07 -07:00
inet: remove old fragmentation hash initializing
2013-10-23 17:01:41 -04:00
tcp/dccp: remove twchain
2013-10-08 23:19:24 -04:00
inet: convert inet_ehash_secret and ipv6_hash_secret to net_get_random_once
2013-10-19 19:45:35 -04:00
netdev: inet_timewait_sock.h missing semi-colon when KMEMCHECK is enabled
2013-10-17 15:56:53 -04:00
inet*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
ipv6: make lookups simpler and faster
2013-10-09 00:01:25 -04:00
net: fix build errors if ipv6 is disabled
2013-10-09 13:04:03 -04:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
2013-11-04 13:48:30 -05:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
2013-10-23 16:49:34 -04:00
tunnels: harmonize cleanup done on skb on xmit path
2013-09-04 00:27:25 -04:00
ip*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
ipv4: generalize gre_handle_offloads
2013-10-19 19:36:18 -04:00
ipvs: avoid rcu_barrier during netns cleanup
2013-10-15 10:36:01 +09:00
ipv6: split inet6_hash_frag for netfilter and initialize secrets with net_get_random_once
2013-10-23 17:01:40 -04:00
ipx.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
iw_handler.h: Remove extern from function prototypes
2013-09-21 14:01:39 -04:00
lapb.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
hostap: Don't use create_proc_read_entry()
2013-04-29 15:41:56 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
llc*.h: Remove extern from function prototypes
2013-09-21 14:01:38 -04:00
mac80211: implement STA CSA for drivers using channel contexts
2013-10-02 18:18:23 +02:00
mac802154: correct a typo in ieee802154_alloc_device() prototype
2013-10-21 18:56:23 -04:00
net: ipv6: mld: get rid of MLDV2_MRC and simplify calculation
2013-09-04 14:53:20 -04:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
2013-10-01 17:06:14 -04:00
ndisc.h: Remove extern from function prototypes
2013-09-21 14:01:39 -04:00
arp/neighbour.h: Remove extern from function prototypes
2013-07-31 17:50:02 -07:00
netfilter: nf_tables: complete net namespace support
2013-10-14 18:00:59 +02:00
netevent/netlink.h: Remove extern from function prototypes
2013-09-21 14:01:39 -04:00
netevent/netlink.h: Remove extern from function prototypes
2013-09-21 14:01:39 -04:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
2013-09-05 14:54:29 -07:00
netrom.h: Remove extern from function prototypes
2013-09-21 14:01:39 -04:00
p8022.h: Remove extern from function prototypes
2013-09-21 14:01:39 -04:00
ping.h: Remove extern from function prototypes
2013-09-23 01:51:07 -04:00
net: Remove extern from include/net/ scheduling prototypes
2013-07-31 17:24:22 -07:00
qdisc: allow setting default queuing discipline
2013-08-31 00:32:32 -04:00
protocol.h: Remove extern from function prototypes
2013-09-23 01:51:08 -04:00
psnap.h: Remove extern from function prototypes
2013-09-23 01:51:08 -04:00
raw/rawv6.h: Remove extern from function prototypes
2013-09-23 01:51:08 -04:00
raw/rawv6.h: Remove extern from function prototypes
2013-09-23 01:51:08 -04:00
regulatory: use RCU to protect last_request
2013-01-03 13:01:30 +01:00
inet: includes a sock_common in request_sock
2013-10-10 00:08:07 -04:00
rose.h: Remove extern from function prototypes
2013-09-23 01:51:08 -04:00
ipv4: introduce new IP_MTU_DISCOVER mode IP_PMTUDISC_INTERFACE
2013-11-05 21:52:27 -05:00
rtnetlink.h: Remove extern from function prototypes
2013-09-23 01:51:09 -04:00
net_sched: add u64 rate to psched_ratecfg_precompute()
2013-09-20 14:41:02 -04:00
scm.h: Remove extern from function prototypes
2013-09-23 01:51:09 -04:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
2013-10-01 17:06:14 -04:00
net: Dereference pointer-value of sk_prot->memory_pressure
2013-10-23 16:15:01 -04:00
stp.h: Remove extern from function prototypes
2013-09-23 01:51:09 -04:00
tcp: properly handle stretch acks in slow start
2013-11-04 19:57:59 -05:00
tcp_memcontrol: Kill struct tcp_memcontrol
2013-10-21 18:43:02 -04:00
transp_v6.h: style neatening
2013-06-04 16:43:42 -07:00
udp: ipv4: Add udp early demux
2013-10-08 16:27:33 -04:00
udplite.h: Remove extern from function prototypes
2013-09-23 16:29:40 -04:00
VSOCK: Move af_vsock.h and vsock_addr.h to include/net
2013-07-27 22:14:06 -07:00
vxlan: Have the NIC drivers do less work for offloads
2013-10-29 02:39:13 -07:00
wext.h: Remove extern from function prototypes
2013-09-23 16:29:40 -04:00
wimax.h: Remove extern from function prototypes
2013-09-23 16:29:41 -04:00
x25.h: Remove extern from function prototypes
2013-09-23 16:29:41 -04:00
ipv6: Add a receive path hook for vti6 in xfrm6_mode_tunnel.
2013-10-09 13:16:36 +02:00
482fc6094a