
­­­­­­­­­­­­­­­­­­
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\me.                 @   sZ  d dl Z d dlZd dlZd dlZd dlZd dlmZ d dlmZ e j	e
ZdZdZdZdZdZdZd	Zd
ZdZdZdZdZdZdZejeZejeZee ZdZdZdZ dZ!d Z"dZ#dZ$dZ%dZ&dZ'dZ(eddddgZ)edddgZ*eddddddgZ+G dd  d e,Z-d!d" Z.d#d$ Z/d3d%d&Z0d'd( Z1d)d* Z2d+d, Z3d-d. Z4d/d0 Z5d1d2 Z6dS )4    N)
namedtuple)util                     i      <   ZIHHIIZBHiII         RTAAttrlengthrta_typedataInterfaceOperstateifname	operstateNetlinkHeadertypeflagsseqpidc               @   s   e Zd ZdZdS )NetlinkCreateSocketErrorz5Raised if netlink socket fails during create or bind.N)__name__
__module____qualname____doc__ r!   r!   /usr/lib/python3.6/netlink.pyr   9   s   r   c              C   sz   y4t j t jt jt j} | jtj tf | jd W n6 t j	k
rj } zd| }t
||W Y dd}~X nX tjd | S )au  Creates netlink socket and bind on netlink group to catch interface
    down/up events. The socket will bound only on RTMGRP_LINK (which only
    includes RTM_NEWLINK/RTM_DELLINK/RTM_GETLINK events). The socket is set to
    non-blocking mode since we're only receiving messages.

    :returns: netlink socket in non-blocking mode
    :raises: NetlinkCreateSocketError
    r   z*Exception during netlink socket create: %sNzCreated netlink socket)socketZ
AF_NETLINKZSOCK_RAWZNETLINK_ROUTEZbindosgetpidRTMGRP_LINKZsetblockingerrorr   LOGdebug)netlink_socketemsgr!   r!   r"   create_bound_netlink_socket=   s    	
r-   c             C   s^   | dk	st dt| tks$t dtjt| dt \}}}}}tjd| t	|||||S )a  Gets netlink message type and length

    :param: data read from netlink socket
    :returns: netlink message type
    :raises: AssertionError if data is None or data is not >= NLMSGHDR_SIZE
    struct nlmsghdr {
               __u32 nlmsg_len;    /* Length of message including header */
               __u16 nlmsg_type;   /* Type of message content */
               __u16 nlmsg_flags;  /* Additional flags */
               __u32 nlmsg_seq;    /* Sequence number */
               __u32 nlmsg_pid;    /* Sender port ID */
    };
    Nzdata is nonez+data is smaller than netlink message headerzGot netlink msg of type %d)
AssertionErrorlenNLMSGHDR_SIZEstructunpackNLMSGHDR_FMTMSG_TYPE_OFFSETr(   r)   r   )r   Zmsg_lenZmsg_typer   r   r   r!   r!   r"   get_netlink_msg_headerS   s    r5   c             C   s^   | dk	st dtj| gg g |\}}}| |kr4dS tjd | jt}|dkrZtjd |S )a  Select and read from the netlink socket if ready.

    :param: netlink_socket: specify which socket object to read from
    :param: timeout: specify a timeout value (integer) to wait while reading,
            if none, it will block indefinitely until socket ready for read
    :returns: string of data read (max length = <MAX_SIZE>) from socket,
              if no data read, returns None
    :raises: AssertionError if netlink_socket is None
    Nznetlink socket is noneznetlink socket ready for readz,Reading from Netlink socket returned no data)r.   selectr(   r)   ZrecvMAX_SIZEr'   )r*   ZtimeoutZread_set_r   r!   r!   r"   read_netlink_socketl   s    



r9   c             C   s   | dk	st dt|ts"t d|tks2t dd }}d}y0tjd| |dd }tjd| |d dd }W n tjk
r   dS X | |t ||  }t|||S )	a(  Unpack a single rta attribute.

    :param: data: string of data read from netlink socket
    :param: offset: starting offset of RTA Attribute
    :return: RTAAttr object with length, type and data. On error, return None.
    :raises: AssertionError if data is None or offset is not integer.
    Nzdata is nonezoffset is not integerz'rta offset is less than expected lengthr   H)offsetr   )	r.   
isinstanceintRTATTR_START_OFFSETr1   unpack_fromr'   RTA_DATA_START_OFFSETr   )r   r;   r   r   Z	attr_datar!   r!   r"   unpack_rta_attr   s    
rA   c             C   s   | dk	st dt| tks$t dd }}t}x|t| krt| |}| sX|jdkrZP t|jt  t }||j| 7 }|jtkrt|j	}q2|jt
kr2tj|j	d}|jd}q2W | s|dkrdS tjd|| t||S )a  Reads Interface name and operational state from RTA Data.

    :param: data: string of data read from netlink socket
    :returns: InterfaceOperstate object containing if_name and oper_state.
              None if data does not contain valid IFLA_OPERSTATE and
              IFLA_IFNAME messages.
    :raises: AssertionError if data is None or length of data is
             smaller than RTATTR_START_OFFSET.
    Nzdata is nonez2length of data is smaller than RTATTR_START_OFFSETr   zutf-8 z!rta attrs: ifname %s operstate %d)r.   r/   r>   rA   r   PAD_ALIGNMENTr   IFLA_OPERSTATEordr   IFLA_IFNAMEr   Zdecode_binarystripr(   r)   r   )r   r   r   r;   attrpadlenZinterface_namer!   r!   r"   read_rta_oper_state   s*    



rJ   c                s6   t jd d fdd}t| dtgttg| S )zBlock until a single nic is attached.

    :param: netlink_socket: netlink_socket to receive events
    :param: existing_nics: List of existing nics so that we can skip them.
    :raises: AssertionError if netlink_socket is none.
    z!Preparing to wait for nic attach.Nc                s   |  krdS | dS )NTFr!   )inamecarrierprevCarrier)existing_nicsr   r!   r"   should_continue_cb   s    z5wait_for_nic_attach_event.<locals>.should_continue_cb)r(   r)   read_netlink_messagesRTM_NEWLINKOPER_UP	OPER_DOWN)r*   rN   rO   r!   )rN   r   r"   wait_for_nic_attach_event   s    
	rT   c                s2   t jd d  fdd}t| dtgtg|  S )zBlock until a single nic is detached and its operational state is down.

    :param: netlink_socket: netlink_socket to receive events.
    z!Preparing to wait for nic detach.Nc                s   |  dS )NFr!   )rK   rL   rM   )r   r!   r"   rO      s    z5wait_for_nic_detach_event.<locals>.should_continue_cb)r(   r)   rP   RTM_DELLINKrS   )r*   rO   r!   )r   r"   wait_for_nic_detach_event   s    
rV   c                sf   | dk	st d dk	s t dt dks4t d fdd}tjd t|  ttgttg| dS )	a  Block until media disconnect and connect has happened on an interface.
    Listens on netlink socket to receive netlink events and when the carrier
    changes from 0 to 1, it considers event has happened and
    return from this function

    :param: netlink_socket: netlink_socket to receive events
    :param: ifname: Interface name to lookout for netlink events
    :raises: AssertionError if netlink_socket is None or ifname is None.
    Nznetlink socket is nonezinterface name is noner   zinterface name cannot be emptyc                s(   |t ko|tk}|r$tjd  dS dS )NzMedia switch happened on %s.FT)rS   rR   r(   r)   )rK   rL   rM   ZisVnetSwitch)r   r!   r"   rO      s
    z=wait_for_media_disconnect_connect.<locals>.should_continue_cbz1Wait for media disconnect and reconnect to happen)	r.   r/   r(   r)   rP   rQ   rU   rR   rS   )r*   r   rO   r!   )r   r"   !wait_for_media_disconnect_connect   s    

rW   c             C   s  | dkrt dt }t}t}xZt| t}|dkr6q"tjdt| ||7 }tjdt| d}	t|}
 x|	|
k rj||	d }t|tk rtjd P t	|}t||j
k rtjd P |j
t d td  @ }|	| }	tjd	|	 |j|krqnt|}|dkrtjd
| qn|dk	r>|j|kr>tjd|j| qn|j|krLqn|}|j}||j||sndS qnW ||	d }q"W dS )a  Reads from the netlink socket until the condition specified by
    the continuation callback is met.

    :param: netlink_socket: netlink_socket to receive events.
    :param: ifname_filter: if not None, will only listen for this interface.
    :param: rtm_types: Type of netlink events to listen for.
    :param: operstates: Operational states to listen.
    :param: should_continue_callback: Specifies when to stop listening.
    NzNetlink socket is nonezread %d bytes from socketzLength of data after concat %dr   z#Data is smaller than netlink headerz*Partial data. Smaller than netlink messager   z"offset to next netlink message: %dz!Failed to read rta attributes: %sz6Ignored netlink event on interface %s. Waiting for %s.)RuntimeErrorbytesrR   r9   SELECT_TIMEOUTr(   r)   r/   r0   r5   r   rC   r   rJ   r   r   )r*   Zifname_filterZ	rtm_typesZ
operstatesZshould_continue_callbackr   rL   rM   Z	recv_datar;   ZdatalenZnl_msgZnlheaderrI   Zinterface_stater!   r!   r"   rP     s`    





rP   )N)7Zloggingr$   r6   r#   r1   collectionsr   Z	cloudinitr   Z	getLoggerr   r(   r&   Z
NLMSG_NOOPZNLMSG_ERRORZ
NLMSG_DONErQ   rU   ZRTM_GETLINKZRTM_SETLINKr7   ZRTA_DATA_OFFSETr4   rZ   r3   ZIFINFOMSG_FMTcalcsizer0   ZIFINFOMSG_SIZEr>   r@   rC   rF   rD   ZOPER_UNKNOWNZOPER_NOTPRESENTrS   ZOPER_LOWERLAYERDOWNZOPER_TESTINGZOPER_DORMANTrR   r   r   r   rX   r   r-   r5   r9   rA   rJ   rT   rV   rW   rP   r!   r!   r!   r"   <module>   sb   



% 