o
    ¯bhC  ã                   @   s  d Z ddlZddlZddlmZ ddlmZmZmZm	Z	m
Z
mZmZmZ ddlmZ ddlmZ ddlmZ ddlmZ dd	lmZ dd
lmZ ddlmZmZmZmZ ddlm Z  dZ!dd„ Z"dZ#dd„ Z$dd„ Z%dd„ Z&G dd„ dƒZ'dd„ Z(eeƒG dd„ dƒƒZ)G dd„ dƒZ*dS )zD
Tools for automated testing of L{twisted.pair}-based applications.
é    N)Údeque)ÚEAGAINÚEBADFÚEINTRÚEINVALÚENOBUFSÚENOSYSÚEPERMÚEWOULDBLOCK©Úwraps)Úimplementer)ÚDatagramProtocol)ÚEthernetProtocol)Ú
IPProtocol)ÚRawUDPProtocol)Ú	_IFNAMSIZÚ
_TUNSETIFFÚTunnelFlagsÚ_IInputOutputSystem)ÚnativeStringé   c                 C   s   t  d| ¡S )zê
    Pack an integer into a network-order two-byte string.

    @param n: The integer to pack.  Only values that fit into 16 bits are
        supported.

    @return: The packed representation of the integer.
    @rtype: L{bytes}
    z>H)ÚstructÚpack)Ún© r   ú6/usr/lib/python3/dist-packages/twisted/pair/testing.pyÚ_H   s   
r   é   c                 C   s   ||  t |ƒ | S )aØ  
    Construct an ethernet frame.

    @param src: The source ethernet address, encoded.
    @type src: L{bytes}

    @param dst: The destination ethernet address, encoded.
    @type dst: L{bytes}

    @param protocol: The protocol number of the payload of this datagram.
    @type protocol: L{int}

    @param payload: The content of the ethernet frame (such as an IP datagram).
    @type payload: L{bytes}

    @return: The full ethernet frame.
    @rtype: L{bytes}
    )r   ©ÚsrcÚdstÚprotocolÚpayloadr   r   r   Ú	_ethernet.   s   r$   c                 C   sœ   dt dt|ƒ ƒ d t dƒ t tjt| ƒ¡ t tjt|ƒ¡ }tt d|¡ƒ}|d? }|d@ | }|dA }|dd	… t 	d
|¡ |dd…  }|| S )aÌ  
    Construct an IP datagram with the given source, destination, and
    application payload.

    @param src: The source IPv4 address as a dotted-quad string.
    @type src: L{bytes}

    @param dst: The destination IPv4 address as a dotted-quad string.
    @type dst: L{bytes}

    @param payload: The content of the IP datagram (such as a UDP datagram).
    @type payload: L{bytes}

    @return: An IP datagram header and payload.
    @rtype: L{bytes}
    s   E é   s      @r   z!10Hé   iÿÿ  Né
   z!Hé   )
r   ÚlenÚsocketÚ	inet_ptonÚAF_INETr   Úsumr   Úunpackr   )r    r!   r#   ÚipHeaderÚchecksumStep1ÚcarryÚchecksumStep2ÚchecksumStep3r   r   r   Ú_ipD   s$   üûù	÷õþ$r4   c                 C   s0   t | ƒt |ƒ t t|ƒd ƒ t dƒ }|| S )a~  
    Construct a UDP datagram with the given source, destination, and
    application payload.

    @param src: The source port number.
    @type src: L{int}

    @param dst: The destination port number.
    @type dst: L{int}

    @param payload: The content of the UDP datagram.
    @type payload: L{bytes}

    @return: A UDP datagram header and payload.
    @rtype: L{bytes}
    é   r   )r   r)   )r    r!   r#   Ú	udpHeaderr   r   r   Ú_udpv   s   þüúþ
r7   c                   @   sr   e Zd ZdZdZeedƒZee	dƒZ
eedƒZeZdZdd„ Zed	d
„ ƒZedd„ ƒZdd„ Zdd„ Zdd„ ZdS )ÚTunnelzè
    An in-memory implementation of a tun or tap device.

    @cvar _DEVICE_NAME: A string representing the conventional filesystem entry
        for the tunnel factory character special device.
    @type _DEVICE_NAME: C{bytes}
    s   /dev/net/tunz Resource temporarily unavailablezOperation would blockzInterrupted function calli   c                 C   s:   || _ || _d| _d| _d| _tƒ | _tƒ | _tƒ | _dS )a  
        @param system: An L{_IInputOutputSystem} provider to use to perform I/O.

        @param openFlags: Any flags to apply when opening the tunnel device.
            See C{os.O_*}.

        @type openFlags: L{int}

        @param fileMode: ignored
        N)	ÚsystemÚ	openFlagsÚ
tunnelModeÚrequestedNameÚnamer   Ú
readBufferÚwriteBufferÚpendingSignals)Úselfr9   r:   ÚfileModer   r   r   Ú__init__¬   s   zTunnel.__init__c                 C   s   | j | jj@  S )zx
        If the file descriptor for this tunnel is open in blocking mode,
        C{True}.  C{False} otherwise.
        )r:   r9   Ú
O_NONBLOCK©rA   r   r   r   ÚblockingÃ   s   zTunnel.blockingc                 C   s   t | j| jj@ ƒS )zz
        If the file descriptor for this tunnel is marked as close-on-exec,
        C{True}.  C{False} otherwise.
        )Úboolr:   r9   Ú	O_CLOEXECrE   r   r   r   ÚcloseOnExecË   s   zTunnel.closeOnExecc                 C   s.   | j tjj@ rtddt|d�}| j |¡ dS )aI  
        Deliver a datagram to this tunnel's read buffer.  This makes it
        available to be read later using the C{read} method.

        @param datagram: The IPv4 datagram to deliver.  If the mode of this
            tunnel is TAP then ethernet framing will be added automatically.
        @type datagram: L{bytes}
        s         s   ÿÿÿÿÿÿr   N)r;   r   ÚIFF_TAPÚvaluer$   Ú_IPv4r>   Úappend©rA   Údatagramr   r   r   ÚaddToReadBufferÓ   s
   
ÿzTunnel.addToReadBufferc                 C   sR   | j r | jtjj@ rd}ndt }|d8 }|| j  ¡ d|…  S | jr&tƒ ‚| j	‚)a  
        Read a datagram out of this tunnel.

        @param limit: The maximum number of bytes from the datagram to return.
            If the next datagram is larger than this, extra bytes are dropped
            and lost forever.
        @type limit: L{int}

        @raise OSError: Any of the usual I/O problems can result in this
            exception being raised with some particular error number set.

        @raise IOError: Any of the usual I/O problems can result in this
            exception being raised with some particular error number set.

        @return: The datagram which was read from the tunnel.  If the tunnel
            mode does not include L{TunnelFlags.IFF_NO_PI} then the datagram is
            prefixed with a 4 byte PI header.
        @rtype: L{bytes}
        ó    ó    r   N)
r>   r;   r   Ú	IFF_NO_PIrK   Ú_PI_SIZEÚpopleftrF   ÚNotImplementedErrorÚnonBlockingExceptionStyle)rA   ÚlimitÚheaderr   r   r   Úreadä   s   zTunnel.readc                 C   sF   | j r| j  ¡  ttdƒ‚t|ƒ| jkrttdƒ‚| j |¡ t|ƒS )a{  
        Write a datagram into this tunnel.

        @param datagram: The datagram to write.
        @type datagram: L{bytes}

        @raise IOError: Any of the usual I/O problems can result in this
            exception being raised with some particular error number set.

        @return: The number of bytes of the datagram which were written.
        @rtype: L{int}
        zInterrupted system callzNo buffer space available)	r@   rU   ÚOSErrorr   r)   ÚSEND_BUFFER_SIZEr   r?   rM   rN   r   r   r   Úwrite  s   


zTunnel.writeN)Ú__name__Ú
__module__Ú__qualname__Ú__doc__Ú_DEVICE_NAMEÚIOErrorr   ÚEAGAIN_STYLEr[   r
   ÚEWOULDBLOCK_STYLEr   ÚEINTR_STYLErW   r\   rC   ÚpropertyrF   rI   rP   rZ   r]   r   r   r   r   r8   ”   s     




#r8   c                    s   t ˆ ƒ‡ fdd„ƒ}|S )a|  
    Wrap a L{MemoryIOSystem} method with permission-checking logic.  The
    returned function will check C{self.permissions} and raise L{IOError} with
    L{errno.EPERM} if the function name is not listed as an available
    permission.

    @param original: The L{MemoryIOSystem} instance to wrap.

    @return: A wrapper around C{original} that applies permission checks.
    c                    s,   ˆ j | jvrttdƒ‚ˆ | g|¢R i |¤ŽS )NzOperation not permitted)r^   Úpermissionsr[   r	   )rA   ÚargsÚkwargs©Úoriginalr   r   ÚpermissionChecker+  s   
z&_privileged.<locals>.permissionCheckerr   )rl   rm   r   rk   r   Ú_privileged  s   rn   c                   @   sz   e Zd ZdZdZdZdZdZdd„ Zdd	„ Z	d
d„ Z
eddd„ƒZdd„ Zdd„ Zdd„ Zedd„ ƒZdd„ Zdd„ ZdS )ÚMemoryIOSystemz÷
    An in-memory implementation of basic I/O primitives, useful in the context
    of unit testing as a drop-in replacement for parts of the C{os} module.

    @ivar _devices:
    @ivar _openFiles:
    @ivar permissions:

    @ivar _counter:
    i    é   é   r   c                 C   s   i | _ i | _ddh| _d S )NÚopenÚioctl)Ú_devicesÚ
_openFilesrh   rE   r   r   r   rC   G  s   zMemoryIOSystem.__init__c                 C   s   | j | ¡  S )aX  
        Get the L{Tunnel} object associated with the given L{TuntapPort}.

        @param port: A L{TuntapPort} previously initialized using this
            L{MemoryIOSystem}.

        @return: The tunnel object created by a prior use of C{open} on this
            object on the tunnel special device file.
        @rtype: L{Tunnel}
        )ru   Úfileno)rA   Úportr   r   r   Ú	getTunnelL  ó   zMemoryIOSystem.getTunnelc                 C   s   || j |< dS )a1  
        Specify a class which will be used to handle I/O to a device of a
        particular name.

        @param name: The filesystem path name of the device.
        @type name: L{bytes}

        @param cls: A class (like L{Tunnel}) to instantiated whenever this
            device is opened.
        N)rt   )rA   r=   Úclsr   r   r   ÚregisterSpecialDeviceY  ry   z$MemoryIOSystem.registerSpecialDeviceNc                 C   sD   || j v r| j}|  jd7  _| j | | ||ƒ| j|< |S ttdƒ‚)aþ  
        A replacement for C{os.open}.  This initializes state in this
        L{MemoryIOSystem} which will be reflected in the behavior of the other
        file descriptor-related methods (eg L{MemoryIOSystem.read},
        L{MemoryIOSystem.write}, etc).

        @param name: A string giving the name of the file to open.
        @type name: C{bytes}

        @param flags: The flags with which to open the file.
        @type flags: C{int}

        @param mode: The mode with which to open the file.
        @type mode: C{int}

        @raise OSError: With C{ENOSYS} if the file is not a recognized special
            device file.

        @return: A file descriptor associated with the newly opened file
            description.
        @rtype: L{int}
        rp   zFunction not implemented)rt   Ú_counterru   r[   r   )rA   r=   ÚflagsÚmodeÚfdr   r   r   rr   f  s   

zMemoryIOSystem.openc                 C   ó,   z	| j |  |¡W S  ty   ttdƒ‚w )z¤
        Try to read some bytes out of one of the in-memory buffers which may
        previously have been populated by C{write}.

        @see: L{os.read}
        úBad file descriptor)ru   rZ   ÚKeyErrorr[   r   )rA   r   rX   r   r   r   rZ   …  ó
   
ÿzMemoryIOSystem.readc                 C   r€   )z’
        Try to add some bytes to one of the in-memory buffers to be accessed by
        a later C{read} call.

        @see: L{os.write}
        r�   )ru   r]   r‚   r[   r   )rA   r   Údatar   r   r   r]   ‘  rƒ   zMemoryIOSystem.writec                 C   s(   z| j |= W dS  ty   ttdƒ‚w )zŠ
        Discard the in-memory buffer and other in-memory state for the given
        file descriptor.

        @see: L{os.close}
        r�   N)ru   r‚   r[   r   )rA   r   r   r   r   Úclose�  s
   
ÿzMemoryIOSystem.closec                 C   sˆ   z| j | }W n ty   ttdƒ‚w |tkrttdƒ‚t dtf |¡\}}||_	||_
|dtd … d |_t dtf |j|¡S )z�
        Perform some configuration change to the in-memory state for the given
        file descriptor.

        @see: L{fcntl.ioctl}
        r�   zRequest or args is not valid.z%dsHNé   s   123)ru   r‚   r[   r   r   r   r   r.   r   r;   r<   r=   r   )rA   r   Úrequestri   Útunnelr=   r~   r   r   r   rs   ©  s   
ÿ
zMemoryIOSystem.ioctlc                 C   sL   d}d}t ||d t||d |d�d�}t| j ¡ ƒ}|d  |¡ ||fS )ah  
        Write an ethernet frame containing an ip datagram containing a udp
        datagram containing the given payload, addressed to the given address,
        to a tunnel device previously opened on this I/O system.

        @param datagram: A UDP datagram payload to send.
        @type datagram: L{bytes}

        @param address: The destination to which to send the datagram.
        @type address: L{tuple} of (L{bytes}, L{int})

        @return: A two-tuple giving the address from which gives the address
            from which the datagram was sent.
        @rtype: L{tuple} of (L{bytes}, L{int})
        z10.1.2.3iaS  r   rp   )r    r!   r#   )r4   r7   Úlistru   ÚvaluesrP   )rA   rO   ÚaddressÚsrcIPÚsrcPortÚ
serializedÚ	openFilesr   r   r   ÚsendUDPÀ  s   ýzMemoryIOSystem.sendUDPc                 C   s
   t | |ƒS )aa  
        Get a socket-like object which can be used to receive a datagram sent
        from the given address.

        @param fileno: A file descriptor representing a tunnel device which the
            datagram will be received via.
        @type fileno: L{int}

        @param host: The IPv4 address to which the datagram was sent.
        @type host: L{bytes}

        @param port: The UDP port number to which the datagram was sent.
            received.
        @type port: L{int}

        @return: A L{socket.socket}-like object which can be used to receive
            the specified datagram.
        )Ú	_FakePort)rA   rv   Úhostrw   r   r   r   Ú
receiveUDPß  s   
zMemoryIOSystem.receiveUDP©N)r^   r_   r`   ra   r|   ÚO_RDWRrD   rH   rC   rx   r{   rn   rr   rZ   r]   r…   rs   r�   r“   r   r   r   r   ro   4  s$    
ro   c                   @   s    e Zd ZdZdd„ Zdd„ ZdS )r‘   zŒ
    A socket-like object which can be used to read UDP datagrams from
    tunnel-like file descriptors managed by a L{MemoryIOSystem}.
    c                 C   s   || _ || _d S r”   )Ú_systemÚ_fileno)rA   r9   rv   r   r   r   rC   û  s   
z_FakePort.__init__c           
         sÌ   | j j| j j ¡ }g ‰ tƒ }‡ fdd„}||_tƒ }| d|¡ t	ƒ ‰ˆ d|¡ | j j| j j
}|tjj@ rEtƒ }| dˆ¡ |j}n‡fdd„}|tjj@  }	|	rZ|td… }||ƒ ˆ d	 d|… S )
a_  
        Receive a datagram sent to this port using the L{MemoryIOSystem} which
        created this object.

        This behaves like L{socket.socket.recv} but the data being I{sent} and
        I{received} only passes through various memory buffers managed by this
        object and L{MemoryIOSystem}.

        @see: L{socket.socket.recv}
        c                    s   ˆ   | ¡ d S r”   )rM   )rO   r‹   )Ú	datagramsr   r   Úcapture  s   z_FakePort.recv.<locals>.capturei90  é   r   c                    s   ˆ   | d d d d ¡S r”   )ÚdatagramReceived)r„   )Úipr   r   Ú<lambda>   s    
ÿz _FakePort.recv.<locals>.<lambda>Nr   )r–   ru   r—   r?   rU   r   r›   r   ÚaddProtor   r;   r   rJ   rK   r   rS   rT   )
rA   Únbytesr„   Úreceiverr™   Úudpr~   Úetherr›   Ú	dataHasPIr   )r˜   rœ   r   Úrecvÿ  s(   z_FakePort.recvN)r^   r_   r`   ra   rC   r¤   r   r   r   r   r‘   õ  s    r‘   )+ra   r*   r   Úcollectionsr   Úerrnor   r   r   r   r   r   r	   r
   Ú	functoolsr   Úzope.interfacer   Útwisted.internet.protocolr   Útwisted.pair.ethernetr   Útwisted.pair.ipr   Útwisted.pair.rawudpr   Útwisted.pair.tuntapr   r   r   r   Útwisted.python.compatr   rT   r   rL   r$   r4   r7   r8   rn   ro   r‘   r   r   r   r   Ú<module>   s4   (2  A