<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/net/ipv4/af_inet.c, branch v3.2.32</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>ipv4: compat_ioctl is local to af_inet.c, make it static</title>
<updated>2011-10-19T23:24:39+00:00</updated>
<author>
<name>Gerrit Renker</name>
<email>gerrit@erg.abdn.ac.uk</email>
</author>
<published>2011-10-15T09:26:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=686dc6b64b58e69715ce92177da0732a6464db69'/>
<id>686dc6b64b58e69715ce92177da0732a6464db69</id>
<content type='text'>
ipv4: compat_ioctl is local to af_inet.c, make it static

Signed-off-by: Gerrit Renker &lt;gerrit@erg.abdn.ac.uk&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
ipv4: compat_ioctl is local to af_inet.c, make it static

Signed-off-by: Gerrit Renker &lt;gerrit@erg.abdn.ac.uk&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: ipv4: relax AF_INET check in bind()</title>
<updated>2011-08-30T22:57:00+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>eric.dumazet@gmail.com</email>
</author>
<published>2011-08-30T22:57:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=29c486df6a208432b370bd4be99ae1369ede28d8'/>
<id>29c486df6a208432b370bd4be99ae1369ede28d8</id>
<content type='text'>
commit d0733d2e29b65 (Check for mistakenly passed in non-IPv4 address)
added regression on legacy apps that use bind() with AF_UNSPEC family.

Relax the check, but make sure the bind() is done on INADDR_ANY
addresses, as AF_UNSPEC has probably no sane meaning for other
addresses.

Bugzilla reference : https://bugzilla.kernel.org/show_bug.cgi?id=42012

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Reported-and-bisected-by: Rene Meier &lt;r_meier@freenet.de&gt;
CC: Marcus Meissner &lt;meissner@suse.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit d0733d2e29b65 (Check for mistakenly passed in non-IPv4 address)
added regression on legacy apps that use bind() with AF_UNSPEC family.

Relax the check, but make sure the bind() is done on INADDR_ANY
addresses, as AF_UNSPEC has probably no sane meaning for other
addresses.

Bugzilla reference : https://bugzilla.kernel.org/show_bug.cgi?id=42012

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
Reported-and-bisected-by: Rene Meier &lt;r_meier@freenet.de&gt;
CC: Marcus Meissner &lt;meissner@suse.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6</title>
<updated>2011-07-06T06:23:37+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2011-07-06T06:23:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e12fe68ce34d60c04bb1ddb1d3cc5c3022388fe4'/>
<id>e12fe68ce34d60c04bb1ddb1d3cc5c3022388fe4</id>
<content type='text'>
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
</pre>
</div>
</content>
</entry>
<entry>
<title>net: bind() fix error return on wrong address family</title>
<updated>2011-07-05T04:37:41+00:00</updated>
<author>
<name>Marcus Meissner</name>
<email>meissner@novell.com</email>
</author>
<published>2011-07-04T01:30:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c349a528cd47e2272ded0ea358363855e86180da'/>
<id>c349a528cd47e2272ded0ea358363855e86180da</id>
<content type='text'>
Hi,

Reinhard Max also pointed out that the error should EAFNOSUPPORT according
to POSIX.

The Linux manpages have it as EINVAL, some other OSes (Minix, HPUX, perhaps BSD) use
EAFNOSUPPORT. Windows uses WSAEFAULT according to MSDN.

Other protocols error values in their af bind() methods in current mainline git as far
as a brief look shows:
	EAFNOSUPPORT: atm, appletalk, l2tp, llc, phonet, rxrpc
	EINVAL: ax25, bluetooth, decnet, econet, ieee802154, iucv, netlink, netrom, packet, rds, rose, unix, x25,
	No check?: can/raw, ipv6/raw, irda, l2tp/l2tp_ip

Ciao, Marcus

Signed-off-by: Marcus Meissner &lt;meissner@suse.de&gt;
Cc: Reinhard Max &lt;max@suse.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Hi,

Reinhard Max also pointed out that the error should EAFNOSUPPORT according
to POSIX.

The Linux manpages have it as EINVAL, some other OSes (Minix, HPUX, perhaps BSD) use
EAFNOSUPPORT. Windows uses WSAEFAULT according to MSDN.

Other protocols error values in their af bind() methods in current mainline git as far
as a brief look shows:
	EAFNOSUPPORT: atm, appletalk, l2tp, llc, phonet, rxrpc
	EINVAL: ax25, bluetooth, decnet, econet, ieee802154, iucv, netlink, netrom, packet, rds, rose, unix, x25,
	No check?: can/raw, ipv6/raw, irda, l2tp/l2tp_ip

Ciao, Marcus

Signed-off-by: Marcus Meissner &lt;meissner@suse.de&gt;
Cc: Reinhard Max &lt;max@suse.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6</title>
<updated>2011-06-21T05:29:08+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2011-06-21T05:29:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9f6ec8d697c08963d83880ccd35c13c5ace716ea'/>
<id>9f6ec8d697c08963d83880ccd35c13c5ace716ea</id>
<content type='text'>
Conflicts:
	drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
	drivers/net/wireless/rtlwifi/pci.c
	net/netfilter/ipvs/ip_vs_core.c
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Conflicts:
	drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
	drivers/net/wireless/rtlwifi/pci.c
	net/netfilter/ipvs/ip_vs_core.c
</pre>
</div>
</content>
</entry>
<entry>
<title>net: rfs: enable RFS before first data packet is received</title>
<updated>2011-06-17T19:27:31+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>eric.dumazet@gmail.com</email>
</author>
<published>2011-06-17T03:45:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=1eddceadb0d6441cd39b2c38705a8f5fec86e770'/>
<id>1eddceadb0d6441cd39b2c38705a8f5fec86e770</id>
<content type='text'>
Le jeudi 16 juin 2011 à 23:38 -0400, David Miller a écrit :
&gt; From: Ben Hutchings &lt;bhutchings@solarflare.com&gt;
&gt; Date: Fri, 17 Jun 2011 00:50:46 +0100
&gt;
&gt; &gt; On Wed, 2011-06-15 at 04:15 +0200, Eric Dumazet wrote:
&gt; &gt;&gt; @@ -1594,6 +1594,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
&gt; &gt;&gt;  			goto discard;
&gt; &gt;&gt;
&gt; &gt;&gt;  		if (nsk != sk) {
&gt; &gt;&gt; +			sock_rps_save_rxhash(nsk, skb-&gt;rxhash);
&gt; &gt;&gt;  			if (tcp_child_process(sk, nsk, skb)) {
&gt; &gt;&gt;  				rsk = nsk;
&gt; &gt;&gt;  				goto reset;
&gt; &gt;&gt;
&gt; &gt;
&gt; &gt; I haven't tried this, but it looks reasonable to me.
&gt; &gt;
&gt; &gt; What about IPv6?  The logic in tcp_v6_do_rcv() looks very similar.
&gt;
&gt; Indeed ipv6 side needs the same fix.
&gt;
&gt; Eric please add that part and resubmit.  And in fact I might stick
&gt; this into net-2.6 instead of net-next-2.6
&gt;

OK, here is the net-2.6 based one then, thanks !

[PATCH v2] net: rfs: enable RFS before first data packet is received

First packet received on a passive tcp flow is not correctly RFS
steered.

One sock_rps_record_flow() call is missing in inet_accept()

But before that, we also must record rxhash when child socket is setup.

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
CC: Tom Herbert &lt;therbert@google.com&gt;
CC: Ben Hutchings &lt;bhutchings@solarflare.com&gt;
CC: Jamal Hadi Salim &lt;hadi@cyberus.ca&gt;
Signed-off-by: David S. Miller &lt;davem@conan.davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Le jeudi 16 juin 2011 à 23:38 -0400, David Miller a écrit :
&gt; From: Ben Hutchings &lt;bhutchings@solarflare.com&gt;
&gt; Date: Fri, 17 Jun 2011 00:50:46 +0100
&gt;
&gt; &gt; On Wed, 2011-06-15 at 04:15 +0200, Eric Dumazet wrote:
&gt; &gt;&gt; @@ -1594,6 +1594,7 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
&gt; &gt;&gt;  			goto discard;
&gt; &gt;&gt;
&gt; &gt;&gt;  		if (nsk != sk) {
&gt; &gt;&gt; +			sock_rps_save_rxhash(nsk, skb-&gt;rxhash);
&gt; &gt;&gt;  			if (tcp_child_process(sk, nsk, skb)) {
&gt; &gt;&gt;  				rsk = nsk;
&gt; &gt;&gt;  				goto reset;
&gt; &gt;&gt;
&gt; &gt;
&gt; &gt; I haven't tried this, but it looks reasonable to me.
&gt; &gt;
&gt; &gt; What about IPv6?  The logic in tcp_v6_do_rcv() looks very similar.
&gt;
&gt; Indeed ipv6 side needs the same fix.
&gt;
&gt; Eric please add that part and resubmit.  And in fact I might stick
&gt; this into net-2.6 instead of net-next-2.6
&gt;

OK, here is the net-2.6 based one then, thanks !

[PATCH v2] net: rfs: enable RFS before first data packet is received

First packet received on a passive tcp flow is not correctly RFS
steered.

One sock_rps_record_flow() call is missing in inet_accept()

But before that, we also must record rxhash when child socket is setup.

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
CC: Tom Herbert &lt;therbert@google.com&gt;
CC: Ben Hutchings &lt;bhutchings@solarflare.com&gt;
CC: Jamal Hadi Salim &lt;hadi@cyberus.ca&gt;
Signed-off-by: David S. Miller &lt;davem@conan.davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>snmp: reduce percpu needs by 50%</title>
<updated>2011-06-11T23:23:59+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>eric.dumazet@gmail.com</email>
</author>
<published>2011-06-10T19:45:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8f0ea0fe3a036a47767f9c80e81b13e379a1f43b'/>
<id>8f0ea0fe3a036a47767f9c80e81b13e379a1f43b</id>
<content type='text'>
SNMP mibs use two percpu arrays, one used in BH context, another in USER
context. With increasing number of cpus in machines, and fact that ipv6
uses per network device ipstats_mib, this is consuming a lot of memory
if many network devices are registered.

commit be281e554e2a (ipv6: reduce per device ICMP mib sizes) shrinked
percpu needs for ipv6, but we can reduce memory use a bit more.

With recent percpu infrastructure (irqsafe_cpu_inc() ...), we no longer
need this BH/USER separation since we can update counters in a single
x86 instruction, regardless of the BH/USER context.

Other arches than x86 might need to disable irq in their
irqsafe_cpu_inc() implementation : If this happens to be a problem, we
can make SNMP_ARRAY_SZ arch dependent, but a previous poll
( https://lkml.org/lkml/2011/3/17/174 ) to arch maintainers did not
raise strong opposition.

Only on 32bit arches, we need to disable BH for 64bit counters updates
done from USER context (currently used for IP MIB)

This also reduces vmlinux size :

1) x86_64 build
$ size vmlinux.before vmlinux.after
   text	   data	    bss	    dec	    hex	filename
7853650	1293772	1896448	11043870	 a8841e	vmlinux.before
7850578	1293772	1896448	11040798	 a8781e	vmlinux.after

2) i386  build
$ size vmlinux.before vmlinux.afterpatch
   text	   data	    bss	    dec	    hex	filename
6039335	 635076	3670016	10344427	 9dd7eb	vmlinux.before
6037342	 635076	3670016	10342434	 9dd022	vmlinux.afterpatch

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
CC: Andi Kleen &lt;andi@firstfloor.org&gt;
CC: Ingo Molnar &lt;mingo@elte.hu&gt;
CC: Tejun Heo &lt;tj@kernel.org&gt;
CC: Christoph Lameter &lt;cl@linux-foundation.org&gt;
CC: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org
CC: linux-arch@vger.kernel.org
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
SNMP mibs use two percpu arrays, one used in BH context, another in USER
context. With increasing number of cpus in machines, and fact that ipv6
uses per network device ipstats_mib, this is consuming a lot of memory
if many network devices are registered.

commit be281e554e2a (ipv6: reduce per device ICMP mib sizes) shrinked
percpu needs for ipv6, but we can reduce memory use a bit more.

With recent percpu infrastructure (irqsafe_cpu_inc() ...), we no longer
need this BH/USER separation since we can update counters in a single
x86 instruction, regardless of the BH/USER context.

Other arches than x86 might need to disable irq in their
irqsafe_cpu_inc() implementation : If this happens to be a problem, we
can make SNMP_ARRAY_SZ arch dependent, but a previous poll
( https://lkml.org/lkml/2011/3/17/174 ) to arch maintainers did not
raise strong opposition.

Only on 32bit arches, we need to disable BH for 64bit counters updates
done from USER context (currently used for IP MIB)

This also reduces vmlinux size :

1) x86_64 build
$ size vmlinux.before vmlinux.after
   text	   data	    bss	    dec	    hex	filename
7853650	1293772	1896448	11043870	 a8841e	vmlinux.before
7850578	1293772	1896448	11040798	 a8781e	vmlinux.after

2) i386  build
$ size vmlinux.before vmlinux.afterpatch
   text	   data	    bss	    dec	    hex	filename
6039335	 635076	3670016	10344427	 9dd7eb	vmlinux.before
6037342	 635076	3670016	10342434	 9dd022	vmlinux.afterpatch

Signed-off-by: Eric Dumazet &lt;eric.dumazet@gmail.com&gt;
CC: Andi Kleen &lt;andi@firstfloor.org&gt;
CC: Ingo Molnar &lt;mingo@elte.hu&gt;
CC: Tejun Heo &lt;tj@kernel.org&gt;
CC: Christoph Lameter &lt;cl@linux-foundation.org&gt;
CC: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org
CC: linux-arch@vger.kernel.org
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net/ipv4: Check for mistakenly passed in non-IPv4 address</title>
<updated>2011-06-02T04:05:22+00:00</updated>
<author>
<name>Marcus Meissner</name>
<email>meissner@suse.de</email>
</author>
<published>2011-06-02T04:05:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d0733d2e29b652b2e7b1438ececa732e4eed98eb'/>
<id>d0733d2e29b652b2e7b1438ececa732e4eed98eb</id>
<content type='text'>
Check against mistakenly passing in IPv6 addresses (which would result
in an INADDR_ANY bind) or similar incompatible sockaddrs.

Signed-off-by: Marcus Meissner &lt;meissner@suse.de&gt;
Cc: Reinhard Max &lt;max@suse.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Check against mistakenly passing in IPv6 addresses (which would result
in an INADDR_ANY bind) or similar incompatible sockaddrs.

Signed-off-by: Marcus Meissner &lt;meissner@suse.de&gt;
Cc: Reinhard Max &lt;max@suse.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: ipv4: add IPPROTO_ICMP socket kind</title>
<updated>2011-05-13T20:08:13+00:00</updated>
<author>
<name>Vasiliy Kulikov</name>
<email>segoon@openwall.com</email>
</author>
<published>2011-05-13T10:01:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c319b4d76b9e583a5d88d6bf190e079c4e43213d'/>
<id>c319b4d76b9e583a5d88d6bf190e079c4e43213d</id>
<content type='text'>
This patch adds IPPROTO_ICMP socket kind.  It makes it possible to send
ICMP_ECHO messages and receive the corresponding ICMP_ECHOREPLY messages
without any special privileges.  In other words, the patch makes it
possible to implement setuid-less and CAP_NET_RAW-less /bin/ping.  In
order not to increase the kernel's attack surface, the new functionality
is disabled by default, but is enabled at bootup by supporting Linux
distributions, optionally with restriction to a group or a group range
(see below).

Similar functionality is implemented in Mac OS X:
http://www.manpagez.com/man/4/icmp/

A new ping socket is created with

    socket(PF_INET, SOCK_DGRAM, PROT_ICMP)

Message identifiers (octets 4-5 of ICMP header) are interpreted as local
ports. Addresses are stored in struct sockaddr_in. No port numbers are
reserved for privileged processes, port 0 is reserved for API ("let the
kernel pick a free number"). There is no notion of remote ports, remote
port numbers provided by the user (e.g. in connect()) are ignored.

Data sent and received include ICMP headers. This is deliberate to:
1) Avoid the need to transport headers values like sequence numbers by
other means.
2) Make it easier to port existing programs using raw sockets.

ICMP headers given to send() are checked and sanitized. The type must be
ICMP_ECHO and the code must be zero (future extensions might relax this,
see below). The id is set to the number (local port) of the socket, the
checksum is always recomputed.

ICMP reply packets received from the network are demultiplexed according
to their id's, and are returned by recv() without any modifications.
IP header information and ICMP errors of those packets may be obtained
via ancillary data (IP_RECVTTL, IP_RETOPTS, and IP_RECVERR). ICMP source
quenches and redirects are reported as fake errors via the error queue
(IP_RECVERR); the next hop address for redirects is saved to ee_info (in
network order).

socket(2) is restricted to the group range specified in
"/proc/sys/net/ipv4/ping_group_range".  It is "1 0" by default, meaning
that nobody (not even root) may create ping sockets.  Setting it to "100
100" would grant permissions to the single group (to either make
/sbin/ping g+s and owned by this group or to grant permissions to the
"netadmins" group), "0 4294967295" would enable it for the world, "100
4294967295" would enable it for the users, but not daemons.

The existing code might be (in the unlikely case anyone needs it)
extended rather easily to handle other similar pairs of ICMP messages
(Timestamp/Reply, Information Request/Reply, Address Mask Request/Reply
etc.).

Userspace ping util &amp; patch for it:
http://openwall.info/wiki/people/segoon/ping

For Openwall GNU/*/Linux it was the last step on the road to the
setuid-less distro.  A revision of this patch (for RHEL5/OpenVZ kernels)
is in use in Owl-current, such as in the 2011/03/12 LiveCD ISOs:
http://mirrors.kernel.org/openwall/Owl/current/iso/

Initially this functionality was written by Pavel Kankovsky for
Linux 2.4.32, but unfortunately it was never made public.

All ping options (-b, -p, -Q, -R, -s, -t, -T, -M, -I), are tested with
the patch.

PATCH v3:
    - switched to flowi4.
    - minor changes to be consistent with raw sockets code.

PATCH v2:
    - changed ping_debug() to pr_debug().
    - removed CONFIG_IP_PING.
    - removed ping_seq_fops.owner field (unused for procfs).
    - switched to proc_net_fops_create().
    - switched to %pK in seq_printf().

PATCH v1:
    - fixed checksumming bug.
    - CAP_NET_RAW may not create icmp sockets anymore.

RFC v2:
    - minor cleanups.
    - introduced sysctl'able group range to restrict socket(2).

Signed-off-by: Vasiliy Kulikov &lt;segoon@openwall.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch adds IPPROTO_ICMP socket kind.  It makes it possible to send
ICMP_ECHO messages and receive the corresponding ICMP_ECHOREPLY messages
without any special privileges.  In other words, the patch makes it
possible to implement setuid-less and CAP_NET_RAW-less /bin/ping.  In
order not to increase the kernel's attack surface, the new functionality
is disabled by default, but is enabled at bootup by supporting Linux
distributions, optionally with restriction to a group or a group range
(see below).

Similar functionality is implemented in Mac OS X:
http://www.manpagez.com/man/4/icmp/

A new ping socket is created with

    socket(PF_INET, SOCK_DGRAM, PROT_ICMP)

Message identifiers (octets 4-5 of ICMP header) are interpreted as local
ports. Addresses are stored in struct sockaddr_in. No port numbers are
reserved for privileged processes, port 0 is reserved for API ("let the
kernel pick a free number"). There is no notion of remote ports, remote
port numbers provided by the user (e.g. in connect()) are ignored.

Data sent and received include ICMP headers. This is deliberate to:
1) Avoid the need to transport headers values like sequence numbers by
other means.
2) Make it easier to port existing programs using raw sockets.

ICMP headers given to send() are checked and sanitized. The type must be
ICMP_ECHO and the code must be zero (future extensions might relax this,
see below). The id is set to the number (local port) of the socket, the
checksum is always recomputed.

ICMP reply packets received from the network are demultiplexed according
to their id's, and are returned by recv() without any modifications.
IP header information and ICMP errors of those packets may be obtained
via ancillary data (IP_RECVTTL, IP_RETOPTS, and IP_RECVERR). ICMP source
quenches and redirects are reported as fake errors via the error queue
(IP_RECVERR); the next hop address for redirects is saved to ee_info (in
network order).

socket(2) is restricted to the group range specified in
"/proc/sys/net/ipv4/ping_group_range".  It is "1 0" by default, meaning
that nobody (not even root) may create ping sockets.  Setting it to "100
100" would grant permissions to the single group (to either make
/sbin/ping g+s and owned by this group or to grant permissions to the
"netadmins" group), "0 4294967295" would enable it for the world, "100
4294967295" would enable it for the users, but not daemons.

The existing code might be (in the unlikely case anyone needs it)
extended rather easily to handle other similar pairs of ICMP messages
(Timestamp/Reply, Information Request/Reply, Address Mask Request/Reply
etc.).

Userspace ping util &amp; patch for it:
http://openwall.info/wiki/people/segoon/ping

For Openwall GNU/*/Linux it was the last step on the road to the
setuid-less distro.  A revision of this patch (for RHEL5/OpenVZ kernels)
is in use in Owl-current, such as in the 2011/03/12 LiveCD ISOs:
http://mirrors.kernel.org/openwall/Owl/current/iso/

Initially this functionality was written by Pavel Kankovsky for
Linux 2.4.32, but unfortunately it was never made public.

All ping options (-b, -p, -Q, -R, -s, -t, -T, -M, -I), are tested with
the patch.

PATCH v3:
    - switched to flowi4.
    - minor changes to be consistent with raw sockets code.

PATCH v2:
    - changed ping_debug() to pr_debug().
    - removed CONFIG_IP_PING.
    - removed ping_seq_fops.owner field (unused for procfs).
    - switched to proc_net_fops_create().
    - switched to %pK in seq_printf().

PATCH v1:
    - fixed checksumming bug.
    - CAP_NET_RAW may not create icmp sockets anymore.

RFC v2:
    - minor cleanups.
    - introduced sysctl'able group range to restrict socket(2).

Signed-off-by: Vasiliy Kulikov &lt;segoon@openwall.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ipv4: Use cork flow in inet_sk_{reselect_saddr,rebuild_header}()</title>
<updated>2011-05-08T21:05:13+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2011-05-06T23:18:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6e869138101bc607e4780187210b79d531f9b2ce'/>
<id>6e869138101bc607e4780187210b79d531f9b2ce</id>
<content type='text'>
These two functions must be invoked only when the socket is locked
(because socket identity modifications are made non-atomically).

Therefore we can use the cork flow for output route lookups.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
These two functions must be invoked only when the socket is locked
(because socket identity modifications are made non-atomically).

Therefore we can use the cork flow for output route lookups.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
