netdev - [PATCH net-next 5/6] sctp: implement prsctp RTX policy

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Sat,  9 Jul 2016 19:47:44 +0800
From:	Xin Long <lucien.xin@...il.com>
To:	network dev <netdev@...r.kernel.org>, linux-sctp@...r.kernel.org
Cc:	Marcelo Ricardo Leitner <marcelo.leitner@...il.com>,
	Vlad Yasevich <vyasevich@...il.com>, daniel@...earbox.net,
	davem@...emloft.net
Subject: [PATCH net-next 5/6] sctp: implement prsctp RTX policy

prsctp RTX policy is a policy to abandon chunks when they are
retransmitted beyond the max count.

This patch uses sent_count to count how many times one chunk has
been sent, and prsctp_param is the max rtx count, which is from
sinfo->sinfo_timetolive in sctp_set_prsctp_policy(). So similar
to TTL policy, if RTX policy is enabled, msg->expire_at won't
work.

Then in sctp_chunk_abandoned, this patch checks if chunk->sent_count
is bigger than chunk->prsctp_param to abandon this chunk.

Signed-off-by: Xin Long <lucien.xin@...il.com>
---
 net/sctp/chunk.c         | 4 ++++
 net/sctp/sm_make_chunk.c | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
index 2698d12..b3692b5 100644
--- a/net/sctp/chunk.c
+++ b/net/sctp/chunk.c
@@ -355,6 +355,10 @@ int sctp_chunk_abandoned(struct sctp_chunk *chunk)
 		else
 			chunk->asoc->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;
 		return 1;
+	} else if (SCTP_PR_RTX_ENABLED(chunk->sinfo.sinfo_flags) &&
+		   chunk->sent_count > chunk->prsctp_param) {
+		chunk->asoc->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
+		return 1;
 	}
 
 	return 0;
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 2c431ee..cfde934 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -720,6 +720,8 @@ static void sctp_set_prsctp_policy(struct sctp_chunk *chunk,
 	if (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags))
 		chunk->prsctp_param =
 			jiffies + msecs_to_jiffies(sinfo->sinfo_timetolive);
+	else if (SCTP_PR_RTX_ENABLED(sinfo->sinfo_flags))
+		chunk->prsctp_param = sinfo->sinfo_timetolive;
 }
 
 /* Make a DATA chunk for the given association from the provided
-- 
2.1.0