From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: [PATCH net-next v2] net: sctp: sctp_verify_init: clean up mandatory checks and add comment Date: Tue, 27 Aug 2013 16:06:03 +0200 Message-ID: <1377612363-10779-1-git-send-email-dborkman@redhat.com> Cc: netdev@vger.kernel.org, linux-sctp@vger.kernel.org To: davem@davemloft.net Return-path: Received: from mx1.redhat.com ([209.132.183.28]:51395 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753351Ab3H0OGG (ORCPT ); Tue, 27 Aug 2013 10:06:06 -0400 Sender: netdev-owner@vger.kernel.org List-ID: Add a comment related to RFC4960 explaning why we do not check for initial TSN, and while at it, remove yoda notation checks and clean up code from checks of mandatory conditions. That's probably just really minor, but makes reviewing easier. Signed-off-by: Daniel Borkmann --- v1->v2: update comment as Neil suggested net/sctp/sm_make_chunk.c | 26 ++++++++++++-------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index 01e9783..e1c1531 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -2240,25 +2240,23 @@ int sctp_verify_init(struct net *net, const struct sctp_association *asoc, struct sctp_chunk **errp) { union sctp_params param; - int has_cookie = 0; + bool has_cookie = false; int result; - /* Verify stream values are non-zero. */ - if ((0 == peer_init->init_hdr.num_outbound_streams) || - (0 == peer_init->init_hdr.num_inbound_streams) || - (0 == peer_init->init_hdr.init_tag) || - (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) { - + /* Check for missing mandatory parameters. Note: Initial TSN is + * also mandatory, but is not checked here since the valid range + * is 0..2**(32-1). RFC4960, section 3.3.3. + */ + if (peer_init->init_hdr.num_outbound_streams == 0 || + peer_init->init_hdr.num_inbound_streams == 0 || + peer_init->init_hdr.init_tag == 0 || + ntohl(peer_init->init_hdr.a_rwnd) < SCTP_DEFAULT_MINWINDOW) return sctp_process_inv_mandatory(asoc, chunk, errp); - } - /* Check for missing mandatory parameters. */ sctp_walk_params(param, peer_init, init_hdr.params) { - - if (SCTP_PARAM_STATE_COOKIE == param.p->type) - has_cookie = 1; - - } /* for (loop through all parameters) */ + if (param.p->type == SCTP_PARAM_STATE_COOKIE) + has_cookie = true; + } /* There is a possibility that a parameter length was bad and * in that case we would have stoped walking the parameters. -- 1.7.11.7