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Obtain all of the avc and policy load messages from the audit
log. This function uses ausearch and requires that the current
process have sufficient rights to run ausearch.
Returns:
string contain all of the audit messages returned by ausearch.
r Nz /proc/uptime�rz%xz%Xz/sbin/ausearchz-mz5AVC,USER_AVC,MAC_POLICY_LOAD,DAEMON_START,SELINUX_ERRz-ts)�stdout)�
subprocess�time�open�float�read�split�closeZ localtimeZstrftime�Popen�PIPE� communicater �PY3� decode_input)r r �fdZoff�sZbootdateZboottime�output� r �/usr/lib/python3.6/audit.py�get_audit_boot_msgs s
r c C s: ddl } | jdddg| jd�j� d }tjr6tj|�}|S )a
Obtain all of the avc and policy load messages from the audit
log. This function uses ausearch and requires that the current
process have sufficient rights to run ausearch.
Returns:
string contain all of the audit messages returned by ausearch.
r Nz/sbin/ausearchz-mz5AVC,USER_AVC,MAC_POLICY_LOAD,DAEMON_START,SELINUX_ERR)r )r r r r r r r )r r r r r �get_audit_msgs2 s
r c C s6 ddl } | jdg| jd�j� d }tjr2tj|�}|S )z�Obtain all of the avc and policy load messages from /bin/dmesg.
Returns:
string contain all of the audit messages returned by dmesg.
r Nz
/bin/dmesg)r )r r r r r r r )r r r r r �get_dmesg_msgsA s
r c @ s e Zd ZdZdd� Zdd� ZdS )� AuditMessagez�Base class for all objects representing audit messages.
AuditMessage is a base class for all audit messages and only
provides storage for the raw message (as a string) and a
parsing function that does nothing.
c C s || _ d| _d S )N� )�message�header)�selfr r r r �__init__W s zAuditMessage.__init__c C s^ xX|D ]P}|j d�}t|�dkr<|dd� dkr|| _dS q|d dkr|d | _dS qW dS ) z�Parse a string that has been split into records by space into
an audit message.
This method should be overridden by subclasses. Error reporting
should be done by raise ValueError exceptions.
�=� N� zaudit(r �msgr )r
�lenr )r �recsr% �fieldsr r r �from_split_string[ s
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__module__� __qualname__�__doc__r! r) r r r r r P s r c @ s e Zd ZdZdd� ZdS )�InvalidMessagez�Class representing invalid audit messages. This is used to differentiate
between audit messages that aren't recognized (that should return None from
the audit message parser) and a message that is recognized but is malformed
in some way.
c C s t j| |� d S )N)r r! )r r r r r r! v s zInvalidMessage.__init__N)r* r+ r, r- r! r r r r r. p s r. c @ s e Zd ZdZdd� Zdd� ZdS )� PathMessagez!Class representing a path messagec C s t j| |� d| _d S )Nr )r r! �path)r r r r r r! { s zPathMessage.__init__c C sX t j| |� xF|D ]>}|jd�}t|�dkr.q|d dkr|d dd� | _d S qW d S )Nr" r# r r0 r ���)r r) r
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S ) �
AVCMessagea� AVC message representing an access denial or granted message.
This is a very basic class and does not represent all possible fields
in an avc message. Currently the fields are:
scontext - context for the source (process) that generated the message
tcontext - context for the target
tclass - object class for the target (only one)
comm - the process name
exe - the on-disc binary
path - the path of the target
access - list of accesses that were allowed or denied
denial - boolean indicating whether this was a denial (True) or granted
(False) message.
ioctlcmd - ioctl 'request' parameter
An example audit message generated from the audit daemon looks like (line breaks
added):
'type=AVC msg=audit(1155568085.407:10877): avc: denied { search } for
pid=677 comm="python" name="modules" dev=dm-0 ino=13716388
scontext=user_u:system_r:setroubleshootd_t:s0
tcontext=system_u:object_r:modules_object_t:s0 tclass=dir'
An example audit message stored in syslog (not processed by the audit daemon - line
breaks added):
'Sep 12 08:26:43 dhcp83-5 kernel: audit(1158064002.046:4): avc: denied { read }
for pid=2 496 comm="bluez-pin" name=".gdm1K3IFT" dev=dm-0 ino=3601333
scontext=user_u:system_r:bluetooth_helper_t:s0-s0:c0
tcontext=system_u:object_r:xdm_tmp_t:s0 tclass=file
c C s\ t j| |� tj� | _tj� | _d| _d| _d| _d| _ d| _
g | _ d| _ d | _
tj| _d S )Nr T)r r! r �SecurityContext�scontext�tcontext�tclass�comm�exer0 �name�accesses�denial�ioctlcmd� audit2why�TERULE�type)r r r r r r! � s
zAVCMessage.__init__c C s| d}|}|t |�d kr&td| j ��x:|t |�k r`|| dkrFd}P | jj|| � |d }q(W |sttd| j ��|d S )NFr z#AVC message in invalid format [%s]
�}T)r& �
ValueErrorr r: �append)r r' �startZ found_close�ir r r Z__parse_access� s zAVCMessage.__parse_accessc C s� t j| |� d}d}d}d}�xftt|��D �]T}|| dkrV| j||d �}d}q,n|| dkrhd| _|| jd�}t|�dkr�q,|d d kr�tj|d �| _ d}q,|d d
kr�tj|d �| _
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�r� Y q,X q,W | �s�| �s�| �s�| �r�td| j ��| j� d S )NF�{r TZgrantedr" r# r r4 r5 r6 r7 r8 r9 r< � z#AVC message in invalid format [%s]
r1 r1 r1 )r r) �ranger& �_AVCMessage__parse_accessr; r
r r3 r4 r5 r6 r7 r8 r9 �intr< rA r �analyze)r r' Z found_srcZ found_tgtZ found_classZ found_accessrD r( r r r r) � sL
z AVCMessage.from_split_stringc C s� | j j� }| jj� }t| j�}g | _||| j|ftj� krXt||| j|f \| _ | _�n�t
j ||| j| j�\| _ | _| j t
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jk�r�| jg| _| jj| j jk�rR| jjd| jj d| j j f� | jj| j jk�r�| j jdk�r�| jjd | jj d | j j f� | jj| j jk�r�| jjd
| jj d
| j j f� | j | jft||| j|f< d S ) NzInvalid Target Context %s
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� z&Error during access vector computationz user (%s)Zobject_rz role (%s)z
level (%s))r5 Z to_stringr4 �tupler: �datar6 �avcdict�keysr? r= rJ ZNOPOLICYr> ZBADTCONrA ZBADSCONZBADPERM�joinZ
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CONSTRAINT�userrB �role�level)r r5 r4 Z access_tupler r r rJ � s8
zAVCMessage.analyzeN)r* r+ r, r- r! rH r) rJ r r r r r2 � s
-r2 c @ s e Zd ZdZdd� ZdS )�PolicyLoadMessagez6Audit message indicating that the policy was reloaded.c C s t j| |� d S )N)r r! )r r r r r r! s zPolicyLoadMessage.__init__N)r* r+ r, r- r! r r r r rT s rT c @ s e Zd ZdZdd� Zdd� ZdS )�DaemonStartMessagez3Audit message indicating that a daemon was started.c C s t j| |� d| _d S )NF)r r! �auditd)r r r r r r! % s zDaemonStartMessage.__init__c C s t j| |� d|krd| _d S )NrV T)r r) rV )r r' r r r r) ) s z$DaemonStartMessage.from_split_stringN)r* r+ r, r- r! r) r r r r rU # s rU c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS ) �ComputeSidMessagea� Audit message indicating that a sid was not valid.
Compute sid messages are generated on attempting to create a security
context that is not valid. Security contexts are invalid if the role is
not authorized for the user or the type is not authorized for the role.
This class does not store all of the fields from the compute sid message -
just the type and role.
c C s4 t j| |� tj� | _tj� | _tj� | _d| _d S )Nr )r r! r r3 �invalid_contextr4 r5 r6 )r r r r r r! 9 s
zComputeSidMessage.__init__c C s� t j| |� t|�dk r td��y\tj|d �| _tj|d jd�d �| _tj|d jd�d �| _ |d jd�d | _
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z;Split string does not represent a valid compute sid message� � r" r � � ) r r) r& rA r r3 rX r
r4 r5 r6 )r r' r r r r) @ s z#ComputeSidMessage.from_split_stringc C s d| j | jf S )Nzrole %s types %s;
)rR r? )r r r r r L s zComputeSidMessage.outputN)r* r+ r, r- r! r) r r r r r rW / s rW c @ s^ e Zd ZdZddd�Zdd� Zdd� Zd d
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d� Z dd� Z
ddd�Z ddd�Z dS )� AuditParsera� Parser for audit messages.
This class parses audit messages and stores them according to their message
type. This is not a general purpose audit message parser - it only extracts
selinux related messages.
Each audit messages are stored in one of four lists:
avc_msgs - avc denial or granted messages. Messages are stored in
AVCMessage objects.
comput_sid_messages - invalid sid messages. Messages are stored in
ComputSidMessage objects.
invalid_msgs - selinux related messages that are not valid. Messages
are stored in InvalidMessageObjects.
policy_load_messages - policy load messages. Messages are stored in
PolicyLoadMessage objects.
These lists will be reset when a policy load message is seen if
AuditParser.last_load_only is set to true. It is assumed that messages
are fed to the parser in chronological order - time stamps are not
parsed.
Fc C s | j � || _d S )N)�_AuditParser__initialize�last_load_only)r r` r r r r! g s zAuditParser.__init__c C s. g | _ g | _g | _g | _g | _i | _d| _d S )NF)�avc_msgs�compute_sid_msgs� invalid_msgs�policy_load_msgs� path_msgs� by_header�check_input_file)r r r r Z __initializek s zAuditParser.__initializec C s� dd� |j � D �}x�|D ]�}d}|dks8|dks8|dkrFt|�}d}n^|dkr\t|�}d}nH|d ksl|d
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r2 rW rT r/ rU �listrg r) rA r. )r �lineZrecrD �foundr% r r r Z __parse_line� s4
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j|� nFt|t �r�| j j|� n.t|t
�r�| jj|� nt|t�r�| jj|� |jdkr�|j| jkr�| j|j j|� n|g| j|j< d S )Nr )�_AuditParser__parse_line�
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zAuditParser.__parsec C sx xr| j j� D ]d}g }d }x0|D ](}t|t�r2|}q t|t�r |j|� q W t|�dkr |r x|D ] }|j|_q`W q W d S )Nr )rf �valuesrp r/ r2 rB r& r0 )r �value�avcr0 r% �ar r r Z__post_process� s
zAuditParser.__post_processc C sL |j � }x|r"| j|� |j � }q
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r N)�readline�_AuditParser__parserg �sys�stderr�write�exit�_AuditParser__post_process)r �inputrm r r r �
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zAuditParser.parse_filec C s. |j d�}x|D ]}| j|� qW | j� dS )z�Parse a string containing audit messages - messages should
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zAuditParser.parse_stringNc C s@ t j� }x2| jD ](}| s$|j|�r|j|jj|jj� qW |S )ao Return RoleAllowSet statements matching the specified filter
Filter out types that match the filer, or all roles
Params:
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output.
Returns:
Access vector set representing the denied access in the
audit logs parsed by this object.
)r Z RoleTypeSetrb �filter�addrX rR r? )r Z role_filterZ
role_typesZcsr r r �to_role� s
zAuditParser.to_roleTc C s� t j� }x�| jD ]�}|jdkr$|r$q| s4|j|�rt j|jj|jj|j g|j
�}|j |_ |j|_|j r�t
j� }|j|j � ||jd< |j||d� qW |S )a� Convert the audit logs access into a an access vector set.
Convert the audit logs into an access vector set, optionally
filtering the restults with the passed in filter object.
Filter objects are object instances with a .filter method
that takes and access vector and returns True if the message
should be included in the final output and False otherwise.
Params:
avc_filter - [optional] Filter object used to filter the
output.
Returns:
Access vector set representing the denied access in the
audit logs parsed by this object.
TZioctl)Z audit_msg)r ZAccessVectorSetra r; r� Z AccessVectorr4 r? r5 r6 r: rM r< r ZXpermSetr� ZxpermsZadd_av)r Z
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zAVCTypeFilter.filterN)r* r+ r, r! r� r r r r r� $ s r� c @ s e Zd Zdd� Zdd� ZdS )�ComputeSidTypeFilterc C s t j|�| _d S )N)r� r� r� )r r� r r r r! 0 s z ComputeSidTypeFilter.__init__c C s@ | j j|jj�rdS | j j|jj�r(dS | j j|jj�r<dS dS )NTF)r� r� rX r? r4 r5 )r rs r r r r� 3 s zComputeSidTypeFilter.filterN)r* r+ r, r! r� r r r r r� / s r� )r� rw r r r r r r r r r. r/ Zselinux.audit2whyr= rN r2 rT rU rW r^ r� r� r r r r �<module> s*
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