P2P: Adjust service discovery maximum fragment size for 60 GHz

In the 60 GHz band, service discovery management frames are sent over
the control PHY and have a smaller maximum frame size (IEEE Std
802.11ad-2012, 21.4.3.2). Fix the code to use sufficiently small
fragment size when operating in the 60 GHz band.

The 60 GHz fragment size (928) is derived from the maximum frame size
for control PHY (1023) and subtracting 48 bytes of header size, and some
spare so we do not reach frames with the absolute maximum size.

Signed-off-by: Lior David <qca_liord@qca.qualcomm.com>

src/p2p/p2p_sd.c

@@ -425,9 +425,16 @@ void p2p_sd_response(struct p2p_data *p2p, int freq, const u8 *dst,
 		     u8 dialog_token, const struct wpabuf *resp_tlvs)
 {
 	struct wpabuf *resp;
+	size_t max_len;
+
+	/*
+	 * In the 60 GHz, we have a smaller maximum frame length for management
+	 * frames.
+	 */
+	max_len = (freq > 56160) ? 928 : 1400;
 
 	/* TODO: fix the length limit to match with the maximum frame length */
-	if (wpabuf_len(resp_tlvs) > 1400) {
+	if (wpabuf_len(resp_tlvs) > max_len) {
 		p2p_dbg(p2p, "SD response long enough to require fragmentation");
 		if (p2p->sd_resp) {
 			/*
@@ -614,7 +621,7 @@ void p2p_rx_gas_comeback_req(struct p2p_data *p2p, const u8 *sa,
 {
 	struct wpabuf *resp;
 	u8 dialog_token;
-	size_t frag_len;
+	size_t frag_len, max_len;
 	int more = 0;
 
 	wpa_hexdump(MSG_DEBUG, "P2P: RX GAS Comeback Request", data, len);
@@ -638,9 +645,14 @@ void p2p_rx_gas_comeback_req(struct p2p_data *p2p, const u8 *sa,
 		return;
 	}
 
+	/*
+	 * In the 60 GHz, we have a smaller maximum frame length for management
+	 * frames.
+	 */
+	max_len = (rx_freq > 56160) ? 928 : 1400;
 	frag_len = wpabuf_len(p2p->sd_resp) - p2p->sd_resp_pos;
-	if (frag_len > 1400) {
-		frag_len = 1400;
+	if (frag_len > max_len) {
+		frag_len = max_len;
 		more = 1;
 	}
 	resp = p2p_build_gas_comeback_resp(dialog_token, WLAN_STATUS_SUCCESS,