From 7613f5fe11c518c16b6b50dabb4964052766b73b Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Tue, 27 Aug 2013 16:53:52 +0200 Subject: [PATCH] net: sctp: sctp_verify_init: clean up mandatory checks and add comment 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 Acked-by: Neil Horman Signed-off-by: David S. Miller --- 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 01e97836ca6..d244a23ab8d 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. -- 2.43.2