Raw socket support in Winsock ?

  • Thread starter Thread starter karthikbalaguru
  • Start date Start date
http://msdn.microsoft.com/en-us/library/ms740548(VS.85).aspx
Click to expand...

Thx for the link !

As per the link, the ability to send traffic over raw sockets
has been restricted in several ways in new Windows
releases after 'Windows XP with SP2' .

The reasons for the below changes w.r.t Raw Sockets
are not clearly mentioned in that link . Any ideas ?
1) TCP data cannot be sent over raw sockets.
But why ?

2) A call to the bind function with a raw socket is not allowed.
But why ? Any ideas ?

But, the below reason w.r.t raw socket & UDP datagram
support is clear -
3) UDP datagrams with an invalid source address cannot be sent
over raw sockets. The IP source address for any outgoing UDP
datagram must exist on a network interface or the datagram is
dropped. This change was made to limit the ability of malicious
code to create distributed denial-of-service attacks and limits the
ability to send spoofed packets (TCP/IP packets with a forged
source IP address).

Thx in advans,
Karthik Balaguru
 
karthikbalaguru said:
Thx for the link !

As per the link, the ability to send traffic over raw sockets
has been restricted in several ways in new Windows
releases after 'Windows XP with SP2' .

The reasons for the below changes w.r.t Raw Sockets
are not clearly mentioned in that link . Any ideas ?
1) TCP data cannot be sent over raw sockets.
But why ?

2) A call to the bind function with a raw socket is not allowed.
But why ? Any ideas ?

But, the below reason w.r.t raw socket & UDP datagram
support is clear -
3) UDP datagrams with an invalid source address cannot be sent
over raw sockets. The IP source address for any outgoing UDP
datagram must exist on a network interface or the datagram is
dropped. This change was made to limit the ability of malicious
code to create distributed denial-of-service attacks and limits the
ability to send spoofed packets (TCP/IP packets with a forged
source IP address).
Click to expand...

It's all to do with security.

Restricted traffic over raw sockets

Detailed description

A very small number of Windows applications make use of raw IP sockets,
which provide an industry-standard way for applications to create TCP/IP
packets with fewer integrity and security checks by the TCP/IP stack.
The Windows implementation of TCP/IP still supports receiving traffic on
raw IP sockets. However, the ability to send traffic over raw sockets
has been restricted in two ways:

* TCP data cannot be sent over raw sockets.

* UDP datagrams with invalid source addresses cannot be sent over raw
sockets. The IP source address for any outgoing UDP datagram must exist
on a network interface or the datagram is dropped.

Why is this change important? What threats does it help mitigate?

This change limits the ability of malicious code to create distributed
denial-of-service attacks and limits the ability to send spoofed
packets, which are TCP/IP packets with a forged source IP address.

[end quote]

http://technet.microsoft.com/en-us/library/bb457156.aspx

John
Click to expand...
 
It's all to do with security.
Click to expand...

Okay. Agreed !!
But, why is this change not present in the
versions earlier to 'Windows XP with SP2' ?

The below link seems to convey that these restrictions
do not apply to Windows Server 2008 , Windows Server
2003, or to versions of the operating system earlier
than Windows XP with SP2 . But, Why ?
http://msdn.microsoft.com/en-us/library/ms740548(VS.85).aspx#
Restricted traffic over raw sockets

Detailed description

A very small number of Windows applications make use of raw IP sockets,
which provide an industry-standard way for applications to create TCP/IP
packets with fewer integrity and security checks by the TCP/IP stack.
The Windows implementation of TCP/IP still supports receiving traffic on
raw IP sockets. However, the ability to send traffic over raw sockets
has been restricted in two ways:

*  TCP data cannot be sent over raw sockets.

*  UDP datagrams with invalid source addresses cannot be sent over raw
sockets. The IP source address for any outgoing UDP datagram must exist
on a network interface or the datagram is dropped.

Why is this change important? What threats does it help mitigate?

This change limits the ability of malicious code to create distributed
denial-of-service attacks and limits the ability to send spoofed
packets, which are TCP/IP packets with a forged source IP address.

[end quote]

http://technet.microsoft.com/en-us/library/bb457156.aspx
Click to expand...

Thx for the link !

The above link conveys that this change helps to limit the
speed at which malicious programs, such as viruses and
worms, spread to uninfected computers as Malicious
programs often attempt to reach uninfected computers
by opening simultaneous connections to random IP
addresses.

Thx in advans,
Karthik Balaguru
Click to expand...
 
karthikbalaguru said:
Okay. Agreed !!
But, why is this change not present in the
versions earlier to 'Windows XP with SP2' ?
Click to expand...

It was changed by way of a security update after SP1 (but before SP2),
but there was a workaround that still allowed users to circumvent the
security fix and still allow traffic over raw sockets. With SP2 it was
decided to plug this workaround too.

Why was this even present in the 'gold' or original RTM Windows XP
version? I don't know, probably because it was thought that there was a
legitimate use and need for this, but maybe after Windows XP was
released Microsoft might have had a change of mind and decided that this
feature should not be enabled on "client" or "consumer" versions of
their operating systems. Before SP2 came about embarrassing security
flaws were being exposed on a regular basis and Microsoft made an all
out effort to plug a lot of holes in Windows XP, the word then was that
almost all other projects were on hold or slowed down while Microsoft
concentrated on security and worked on SP2 for Windows XP, even Vista's
release was pushed back while Microsoft worked at securing their
flagship product.

For all it's worth Unix and Linux permit traffic over raw sockets and
the Windows server versions also allow this, although I'm unsure if
Server 2008 still allows it. I think that it's probably just that with
all kinds of bumbling users on XP a decision was made to "protect the
users from themselves" so they plugged up raw sockets as a preemptive
strike against possible exploits. But that is just what I think at this
time... I don't know the exact reasons behind these decisions.

John
 
John John

W2K8 R2 does allow it but not W2K8 stand alone except for the Enterprise version
 
John John

W2K8 R2 does allow it but not W2K8 stand alone except for the Enterpriseversion
Click to expand...

Would cygwin also not support the Raw
sockets as Winsock has been is used by
it ?

But, i need raw socket for an application
that i am trying to execute from cygwin in
'Windows XP with SP2' & Vista . How can
this be achieved ?

In Iinux, it seems that there is restriction at
user-level (root/normal user) to use the raw
sockets. So, it was not a problem.

Thx in advans,
Karthik Balaguru
 
karthikbalaguru said:
Would cygwin also not support the Raw
sockets as Winsock has been is used by
it ?
Click to expand...

Ask the folks in the cygwin help groups, they may know of a workaround.

But, i need raw socket for an application
that i am trying to execute from cygwin in
'Windows XP with SP2' & Vista . How can
this be achieved ?
Click to expand...

Use a driver that doesn't use the Windows TCP/IP stack, maybe try WinPcap.

In Iinux, it seems that there is restriction at
user-level (root/normal user) to use the raw
sockets. So, it was not a problem.
Click to expand...

That is also sort of how NT4/Windows 2000 and Windows XP Pro did it, it
was/is only allowed with administrative privileges. But for SP2 and
later it was plugged for all users on XP.

John
 
Ask the folks in the cygwin help groups, they may know of a workaround.
Click to expand...

Okay, I checked with cygwin help groups.
http://www.cygwin.com/ml/cygwin/2010-01/msg00183.html
Use a driver that doesn't use the Windows TCP/IP stack, maybe try WinPcap..
Click to expand...

This seems to the right approach !
WinPcap for raw sockets in windows seems
to be the only only way out as of now !
That is also sort of how NT4/Windows 2000 and Windows XP Pro did it, it
was/is only allowed with administrative privileges.  But for SP2 and
later it was plugged for all users on XP.
Click to expand...

I wonder how linux is secure without plugging
off while windows had to plug off to be secure !

Thx,
Karthik Balaguru
 
Back
Top