[PATCH 2/3] P2P: always re-select oper channel if not hard coded

[Arik Nemtsov]

Since the operating channel is randomly set to 1/6/11 on init, which is
always in the channel intersection, we were effectively ignoring the set
of p2p preferred channels.
Fix this by trying to get the best channel we can, unless the user hard
coded the operating channel in the configuration file. Fall back to the
initial randomly selected channel if a better one cannot be chosen.

Signed-hostap: Arik Nemtsov <arik at wizery.com>
---
 src/p2p/p2p_go_neg.c |   17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/p2p/p2p_go_neg.c b/src/p2p/p2p_go_neg.c
index 031b3a1..e1ba466 100644
--- a/src/p2p/p2p_go_neg.c
+++ b/src/p2p/p2p_go_neg.c
@@ -391,6 +391,20 @@ static void p2p_reselect_channel(struct p2p_data *p2p,
 	}
 
 	/*
+	 * Try to see if the original channel is in the intersection. If
+	 * so, no need to change anything, as it already contains some
+	 * randomness.
+	 */
+	if (p2p_channels_includes(intersection, p2p->op_reg_class,
+				  p2p->op_channel)) {
+		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
+			"P2P: Using original operating class and channel "
+			"(reg_class %u channel %u) from intersection",
+			p2p->op_reg_class, p2p->op_channel);
+		return;
+	}
+
+	/*
 	 * Fall back to whatever is included in the channel intersection since
 	 * no better options seems to be available.
 	 */
@@ -639,7 +653,8 @@ void p2p_process_go_neg_req(struct p2p_data *p2p, const u8 *sa,
 				wpa_hexdump(MSG_DEBUG, "P2P: channels",
 					    c->channel, c->channels);
 			}
-			if (!p2p_channels_includes(&intersection,
+			if (!p2p->cfg->cfg_op_channel ||
+			    !p2p_channels_includes(&intersection,
 						   p2p->op_reg_class,
 						   p2p->op_channel))
 				p2p_reselect_channel(p2p, &intersection);
-- 
1.7.9.5