lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 21 Feb 2008 09:09:18 +0000
From:	Gerrit Renker <>
Subject: [DCCP] [Patch 0/10]: Finish and repair existing Ack Vector implementation

This is a re-packaged resubmission (reduction from about 20 small patches) of the
Ack Vector patch set, which accomplishes two main things.

 First, it completes the implementation of a circular Ack Vector buffer. So far
 the buffer was implemented as a linear array which dropped packets on overflow.

 Second, it makes the Ack Vector implementation workable for Ack Ratios greater
 than 1. The code does not currently work when Ack Ratio is greater than 1.
 The reason that existing problems were not observed is that the main module 
 sets Ack Ratio to 1, which in effect bypasses Ack Vectors entirely.
 Several bugs with regard to a basic implementation of RFC 4340 Ack Vectors
 were fixed and protections against corrupting buffer state added:
 * successive overlapping Ack Vectors were corrupting buffer state;
 * a protection against outdated entries was missing;
 * a modification was necessary to compute ECN nonces over multiple vectors;
 * reserving entries (one per packet) didn't work well with large burst losses;
A summary of the problems that were fixed and full code documentation is on

The code has been tested extensively and has been part of the test tree for over
two months.

Ack Vectors are a necessary requirement of CCID-2, so it expected that CCID-2
can subsequently also be improved.
 Short summary
 Patch # 1: Fixes an oversight: Ack Vectors need to be ignored as long as
            feature-negotiation is processing.
 Patch # 2: Ack Vector interface clean-up -- preparation for subsequent patches.
 Patch # 3: Separates Ack Vector - specific code from option-inserting code.
 Patch # 4: Completes the implementation of a fully circular Ack Vector buffer. 
 Patch # 5: Adds a tested algorithm to update Ack Vector buffer state.
 Patch # 6: Updates and revises the way new Ack Vector information is registered.
 Patch # 7: Consolidates Ack Vector processing within DCCP main module.
 Patch # 8: Adds a fallback solution - scheduling a Sync when out-of-space.
 Patch # 9: Removes older and now unused parts of the Ack Vector infrastructure.
 Patch #10: Separates the task of parsing Ack Vectors from the CCID(-2) code.

The revised patch set has been uploaded to
	git:// 	[dccp]
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to
More majordomo info at

Powered by blists - more mailing lists