netdev - [RFC PATCH 0/2] Faster/parallel SYN handling to mitigate SYN floods

lists.openwall.net		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 linux-hardening linux-cve-announce 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]

Message-ID: <20120528115102.12068.79994.stgit@localhost.localdomain>
Date:	Mon, 28 May 2012 13:52:16 +0200
From:	Jesper Dangaard Brouer <brouer@...hat.com>
To:	Jesper Dangaard Brouer <brouer@...hat.com>, netdev@...r.kernel.org,
	Christoph Paasch <christoph.paasch@...ouvain.be>,
	Eric Dumazet <eric.dumazet@...il.com>,
	"David S. Miller" <davem@...emloft.net>,
	Martin Topholm <mph@...h.dk>
Cc:	Florian Westphal <fw@...len.de>, opurdila@...acom.com,
	Hans Schillstrom <hans.schillstrom@...csson.com>
Subject: [RFC PATCH 0/2] Faster/parallel SYN handling to mitigate SYN floods

The following series is a RFC (Request For Comments) for implementing
a faster and parallel handling of TCP SYN connections, to mitigate SYN
flood attacks.  This is against DaveM's net (f0d1b3c2bc), as net-next
is closed, as DaveM has mentioned numerous times ;-)

Only IPv4 TCP is handled here. The IPv6 TCP code also need to be
updated, but I'll deal with that part after we have agreed on a
solution for IPv4 TCP.

 Patch 1/2: Is a cleanup, where I split out the SYN cookie handling
  from tcp_v4_conn_request() into tcp_v4_syn_conn_limit().

 Patch 2/2: Move tcp_v4_syn_conn_limit() outside bh_lock_sock() in
  tcp_v4_rcv().  I would like some input on, (1) if this safe without
  the lock, (2) if we need to do some sock lookup, before calling
  tcp_v4_syn_conn_limit() (Christoph Paasch
  <christoph.paasch@...ouvain.be> mentioned something about SYN
  retransmissions)

---

Jesper Dangaard Brouer (2):
      tcp: Early SYN limit and SYN cookie handling to mitigate SYN floods
      tcp: extract syncookie part of tcp_v4_conn_request()

 net/ipv4/tcp_ipv4.c |  131 ++++++++++++++++++++++++++++++++++++++++++---------
 1 files changed, 107 insertions(+), 24 deletions(-)

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html