dpp-nfc: Reuse the same handover client for alternative URI

Postpone closing of the handover client to allow the same client to be
used for sending both handover request messages if an alternative URI
needs to be tried.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>

wpa_supplicant/examples/dpp-nfc.py

@@ -30,6 +30,8 @@ in_raw_mode = False
 prev_tcgetattr = 0
 no_input = False
 srv = None
+hs_client = None
+need_client = False
 continue_loop = True
 terminate_now = False
 summary_file = None
@@ -41,7 +43,9 @@ hs_sent = False
 netrole = None
 operation_success = False
 mutex = threading.Lock()
+client_mutex = threading.Lock()
 no_alt_proposal = False
+i_m_selector = False
 
 C_NORMAL = '\033[0m'
 C_RED = '\033[91m'
@@ -248,6 +252,19 @@ def wpas_report_handover_sel(uri):
     return wpas.request(cmd)
 
 def dpp_handover_client(llc, alt=False):
+    summary("About to start run_dpp_handover_client (alt=%s)" % str(alt))
+    if alt:
+        global need_client
+        need_client = True
+    with client_mutex:
+        summary("Start run_dpp_handover_client (client_mutex held; alt=%s))" % str(alt))
+        if alt:
+            global i_m_selector
+            i_m_selector = False
+        run_dpp_handover_client(llc, alt)
+        summary("Done run_dpp_handover_client (alt=%s)" % str(alt))
+
+def run_dpp_handover_client(llc, alt=False):
     chan_override = None
     global alt_proposal_used
     if alt:
@@ -284,6 +301,12 @@ def dpp_handover_client(llc, alt=False):
     if peer_crn is not None and not alt:
         summary("NFC handover request from peer was already received - do not send own")
         return
+    global hs_client
+    if hs_client:
+        summary("Use already started handover client")
+        client = hs_client
+    else:
+        summary("Start handover client")
         client = nfc.handover.HandoverClient(llc)
         try:
             summary("Trying to initiate NFC connection handover")
@@ -297,20 +320,21 @@ def dpp_handover_client(llc, alt=False):
             summary("Other exception: " + str(e))
             client.close()
             return
+        hs_client = client;
 
     if peer_crn is not None and not alt:
         summary("NFC handover request from peer was already received - do not send own")
-        client.close()
         return
 
     summary("Sending handover request")
 
-    global my_crn, my_crn_ready, hs_sent
+    global my_crn, my_crn_ready, hs_sent, need_client
     my_crn_ready = True
 
     if not client.send_records(message):
         my_crn_ready = False
         summary("Failed to send handover request", color=C_RED)
+        hs_client = None
         client.close()
         return
 
@@ -333,19 +357,27 @@ def dpp_handover_client(llc, alt=False):
             summary("No response received as expected since I'm the handover server")
         elif alt_proposal_used and not alt:
             summary("No response received for initial proposal as expected since alternative proposal was also used")
+        elif need_client:
+            summary("No response received, but handover client is still needed")
         else:
             summary("No response received", color=C_RED)
+            hs_client = None
             client.close()
         return
     summary("Received message: " + str(message))
     if len(message) < 1 or \
        not isinstance(message[0], ndef.HandoverSelectRecord):
         summary("Response was not Hs - received: " + message.type)
+        hs_client = None
         client.close()
         return
 
     summary("Received handover select message")
     summary("alternative carriers: " + str(message[0].alternative_carriers))
+    global i_m_selector
+    if i_m_selector:
+        summary("Ignore the received select since I'm the handover selector")
+        return
 
     if alt_proposal_used and not alt:
         summary("Ignore received handover select for the initial proposal since alternative proposal was sent")
@@ -412,11 +444,13 @@ def dpp_handover_client(llc, alt=False):
         my_crn = None
         peer_crn = None
         hs_sent = False
+        hs_client = None
         client.close()
         summary("Returning from dpp_handover_client")
         return
 
     summary("Remove peer")
+    hs_client = None
     client.close()
     summary("Done with handover")
     global only_one
@@ -477,7 +511,8 @@ class HandoverServer(nfc.handover.HandoverServer):
             if ((my_crn & 1) == (peer_crn & 1) and my_crn > peer_crn) or \
                ((my_crn & 1) != (peer_crn & 1) and my_crn < peer_crn):
                 summary("I'm the Handover Selector Device")
-                pass
+                global i_m_selector
+                i_m_selector = True
             else:
                 summary("Peer is the Handover Selector device")
                 summary("Ignore the received request.")
@@ -799,7 +834,7 @@ def llcp_startup(llc):
 def llcp_connected(llc):
     summary("P2P LLCP connected")
     global wait_connection, my_crn, peer_crn, my_crn_ready, hs_sent
-    global no_alt_proposal, alt_proposal_used
+    global no_alt_proposal, alt_proposal_used, need_client, i_m_selector
     wait_connection = False
     my_crn_ready = False
     my_crn = None
@@ -807,6 +842,8 @@ def llcp_connected(llc):
     hs_sent = False
     no_alt_proposal = False
     alt_proposal_used = False
+    need_client = False
+    i_m_selector = False
     global srv
     srv.start()
     if init_on_touch or not no_input:
@@ -815,6 +852,10 @@ def llcp_connected(llc):
 
 def llcp_release(llc):
     summary("LLCP release")
+    global hs_client
+    if hs_client:
+        hs_client.close()
+        hs_client = None
     return True
 
 def terminate_loop():