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                """Utilities module for of_core OpenFlow v0x04 operations."""  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    2
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                from pyof.v0x04.common.action import ControllerMaxLen  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    3
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                from pyof.v0x04.controller2switch.common import ConfigFlag, MultipartType  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    4
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                from pyof.v0x04.controller2switch.multipart_request import (FlowStatsRequest,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    5
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                                                                            MultipartRequest)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    6
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                from pyof.v0x04.controller2switch.set_config import SetConfig  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    7
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                from pyof.v0x04.symmetric.echo_request import EchoRequest  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    8
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                from pyof.v0x04.symmetric.hello import Hello  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                from kytos.core.events import KytosEvent  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                from kytos.core.interface import Interface  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    12
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                from napps.kytos.of_core.utils import emit_message_out  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                def update_flow_list(controller, switch):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    """Request flow stats from switches.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    Args:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    19
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                        controller(:class:`~kytos.core.controller.Controller`):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            the controller being used.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    21
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                        switch(:class:`~kytos.core.switch.Switch`):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    22
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                            target to send a stats request.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    Returns:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    25
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                        int: multipart request xid  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    26
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                    27
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                    """  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    28
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                    multipart_request = MultipartRequest()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    29
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                    multipart_request.multipart_type = MultipartType.OFPMP_FLOW  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    30
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                    multipart_request.body = FlowStatsRequest()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    emit_message_out(controller, switch.connection, multipart_request)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    32
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                    return multipart_request.header.xid  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    35
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                             1                          | 
                
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                def send_desc_request(controller, switch):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    36
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                    """Request vendor-specific switch description.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    37
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                    38
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                    Args:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    39
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                        controller(:class:`~kytos.core.controller.Controller`):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    40
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                            the controller being used.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    41
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                        switch(:class:`~kytos.core.switch.Switch`):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    42
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                            target to send a stats request.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    43
                 | 
                                    
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                    """  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    44
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                    multipart_request = MultipartRequest()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    45
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                    multipart_request.multipart_type = MultipartType.OFPMP_DESC  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    46
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                    emit_message_out(controller, switch.connection, multipart_request)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    47
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                    48
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                    49
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                             1                          | 
                
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                def send_port_request(controller, connection):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    50
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                    """Send a Port Description Request after the Features Reply."""  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    51
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                    port_request = MultipartRequest()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    52
                 | 
                                    
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                    port_request.multipart_type = MultipartType.OFPMP_PORT_DESC  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    53
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                    emit_message_out(controller, connection, port_request)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    54
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                    55
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                    56
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                             1                          | 
                
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                def handle_features_reply(controller, event):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    57
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                    """Handle OF v0x04 features_reply message events.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    58
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                    59
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                    This is the end of the Handshake workflow of the OpenFlow Protocol.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    60
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                    61
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                    Parameters:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    62
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                        controller (Controller): Controller being used.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    63
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                        event (KytosEvent): Event with features reply message.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    64
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                    65
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                    """  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    66
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                    connection = event.source  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    67
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                    features_reply = event.content['message']  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    68
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                    dpid = features_reply.datapath_id.value  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    69
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                    70
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                    switch = controller.get_switch_or_create(dpid=dpid,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    71
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                                                             connection=connection)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    72
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                    send_port_request(controller, connection)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    73
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                    74
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                    switch.update_features(features_reply)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    75
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                    76
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                    return switch  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    77
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                    78
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                    79
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                             1                          | 
                
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                def handle_port_desc(controller, switch, port_list):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    80
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                    """Update interfaces on switch based on port_list information."""  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    81
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                    for port in port_list:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    82
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                        interface = switch.get_interface_by_port_no(port.port_no.value)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    83
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                        if interface:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    84
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                            interface.name = port.name.value  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    85
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                            interface.address = port.hw_addr.value  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    86
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                            interface.state = port.state.value  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    87
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                            interface.features = port.curr  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    88
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                        else:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    89
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                            interface = Interface(name=port.name.value,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    90
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                                                  address=port.hw_addr.value,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    91
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                                                  port_number=port.port_no.value,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    92
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                                                  switch=switch,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    93
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                                                  state=port.state.value,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    94
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                                                  features=port.curr)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    95
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                        switch.update_interface(interface)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    96
                 | 
                                    
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                        port_event = KytosEvent(name='kytos/of_core.switch.port.created',  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    97
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                                                content={ | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    98
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                                                    'switch': switch.id,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    99
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                                                    'port': port.port_no.value,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    100
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                                                    'port_description': { | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    101
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                                                        'alias': port.name.value,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    102
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                                                        'mac': port.hw_addr.value,  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    103
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                                                        'state': port.state.value  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    104
                 | 
                                    
                                                     | 
                
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                                                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    105
                 | 
                                    
                                                     | 
                
                 | 
                                                    })  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    106
                 | 
                                    
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                 | 
                        controller.buffers.app.put(port_event)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    107
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                | 
                    108
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                | 
                    109
                 | 
                                    
                             1                          | 
                
                 | 
                def send_echo(controller, switch):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    110
                 | 
                                    
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                 | 
                    """Send echo request to a datapath.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    111
                 | 
                                    
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                 | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    112
                 | 
                                    
                                                     | 
                
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                    Keep the connection alive through symmetric echoes.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    113
                 | 
                                    
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                 | 
                    """  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    114
                 | 
                                    
                                                     | 
                
                 | 
                    echo = EchoRequest(data=b'kytosd_13')  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    115
                 | 
                                    
                                                     | 
                
                 | 
                    emit_message_out(controller, switch.connection, echo)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    116
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                    117
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                | 
                    118
                 | 
                                    
                             1                          | 
                
                 | 
                def send_set_config(controller, switch):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    119
                 | 
                                    
                                                     | 
                
                 | 
                    """Send a SetConfig message after the OpenFlow handshake."""  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    120
                 | 
                                    
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                 | 
                    set_config = SetConfig()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    121
                 | 
                                    
                                                     | 
                
                 | 
                    set_config.flags = ConfigFlag.OFPC_FRAG_NORMAL  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    122
                 | 
                                    
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                 | 
                    set_config.miss_send_len = ControllerMaxLen.OFPCML_NO_BUFFER  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    123
                 | 
                                    
                                                     | 
                
                 | 
                    emit_message_out(controller, switch.connection, set_config)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    124
                 | 
                                    
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                | 
                    125
                 | 
                                    
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                | 
                    126
                 | 
                                    
                             1                          | 
                
                 | 
                def say_hello(controller, connection):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    127
                 | 
                                    
                                                     | 
                
                 | 
                    """Send back a Hello packet with the same version as the switch."""  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    128
                 | 
                                    
                                                     | 
                
                 | 
                    hello = Hello()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    129
                 | 
                                    
                                                     | 
                
                 | 
                    emit_message_out(controller, connection, hello)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    130
                 | 
                                    
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                 | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
                | 
                    131
                 | 
                                    
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                 | 
            
            
                                                                        
                            
            
                                    
            
            
                | 
                    132
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                             1                          | 
                
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                def mask_to_bytes(mask, size):  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    133
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                    """Return the mask in bytes."""  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    134
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                    bits = 0  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    135
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                    for i in range(size-mask, size):  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    136
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                        bits |= (1 << i)  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    137
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                    tobytes = bits.to_bytes(size//8, 'big')  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    138
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                    return tobytes  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    139
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                    140
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                    141
                 | 
                                    
                             1                          | 
                
                View Code Duplication | 
                def bytes_to_mask(tobytes, size):  | 
            
                            
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                    142
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                    """Return the mask in string."""  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    143
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                    int_mask = int.from_bytes(tobytes, 'big')  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    144
                 | 
                                    
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                    bits = bin(int_mask)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    145
                 | 
                                    
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                    strbits = str(bits)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    146
                 | 
                                    
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                    strbits = strbits[2:]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    147
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                    netmask = 0  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    148
                 | 
                                    
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                    for i in range(size):  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    149
                 | 
                                    
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                        if strbits[i] == '1':  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    150
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                            netmask += 1  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    151
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                        else:  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    152
                 | 
                                    
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                 | 
                            break  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
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                    153
                 | 
                                    
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                 | 
                    return netmask  | 
            
            
                                                        
            
                                    
            
            
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                    154
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