class StateBasedChainer(MultiTargetChainer):
"""<class maturity="stable" abstract="yes">
<summary>
Class encapsulating connection establishment with multiple
target addresses and keeping down state between connects.
</summary>
<description>
<para>
This class encapsulates a real TCP/IP connection
establishment, and is used when a top-level proxy wants to
perform chaining. In addition to ConnectChainer, this class
adds the capability to perform stateful, load balance
server connections among a set of IP addresses.
</para>
<note>
<para>Both the <link linkend="python.Chainer.FailoverChainer">FailoverChainer</link>
and <link linkend="python.Chainer.RoundRobinChainer">RoundRobinChainer</link>
classes are derived from StateBasedChainer.</para>
</note>
</description>
<metainfo>
<attributes>
<attribute internal="yes">
<name>state</name>
<type></type>
<description>Down state of target hosts.
</description>
</attribute>
</attributes>
</metainfo>
</class>
"""
def __init__(self,
protocol=ZD_PROTO_AUTO,
timeout_connect=None,
timeout_state=None):
"""<method maturity="stable">
<summary>
Constructor to initialize a StateBasedChainer instance.
</summary>
<description>
<para>
This constructor initializes a StateBasedChainer class by
filling arguments with appropriate values and calling the
inherited constructor.
</para>
</description>
<metainfo>
<arguments>
<argument maturity="stable">
<name>protocol</name>
<type>
<link id="zorp.proto.id"/>
</type>
<default>ZD_PROTO_AUTO</default>
<description>
Optional, specifies connection protocol (<parameter>
ZD_PROTO_TCP</parameter> or <parameter>ZD_PROTO_UDP
</parameter>), when not specified it
defaults to the same protocol used on the
client side.
</description>
</argument>
<argument>
<name>timeout_connect</name>
<type>
<integer/>
</type>
<default>30000</default>
<description>
Specifies connection timeout to be used when
connecting to the target server.
</description>
</argument>
<argument>
<name>timeout_state</name>
<type>
<integer/>
</type>
<default>60000</default>
<description>
The down state of remote hosts is kept for this interval in miliseconds.
</description>
</argument>
</arguments>
</metainfo>
</method>
"""
MultiTargetChainer.__init__(self, protocol, timeout_connect)
if not timeout_state:
timeout_state = 60000
self.state = TimedCache('chainer-state',
int((timeout_state + 999) / 1000),
update_stamp=FALSE)
def getNextTarget(self, session):
"""<method internal="yes">
</method>
"""
while 1:
(target_local,
target_remote) = MultiTargetChainer.getNextTarget(self, session)
if not target_remote:
# we enumerated all targets
try:
session.chainer_targets_enumerated = session.chainer_targets_enumerated + 1
except AttributeError:
session.chainer_targets_enumerated = 1
if not self.state or session.chainer_targets_enumerated == 2:
# we enumerated all our targets twice, once
# with state held, and then all state
# cleared, we were not successful, terminate
# target iteration
log(
None, CORE_MESSAGE, 4,
"All destinations are down for two full iterations, giving up;"
)
return (None, None)
## LOG ##
# This message reports that the remote end is down and Zorp stores the
# down state of the remote end, so Zorp wont try to connect to it within the
# timeout latter.
##
log(
None, CORE_MESSAGE, 4,
"All destinations are down, clearing cache and trying again;"
)
# we enumerated all targets, and all of them were
# down, clear our state and try once more
self.state.clear()
self.restart(session)
continue
is_host_down = self.state.lookup(target_remote.ip_s)
if not is_host_down:
return (target_local, target_remote)
else:
## LOG ##
# This message reports that the remote end is down, but Zorp does not store the
# down state of the remote end, so Zorp will try to connect to it next time.
##
log(session.session_id, CORE_MESSAGE, 4,
"Destination is down, skipping; remote='%s'",
(target_remote, ))
def disableTarget(self, session, target_local, target_remote):
"""<method internal="yes">
</method>
"""
## LOG ##
# This message reports that the remote end is down and Zorp stores the
# down state of the remote end, so Zorp wont try to connect to it within the
# timeout latter.
##
log(session.session_id, CORE_MESSAGE, 4,
"Destination is down, keeping state; remote='%s'",
(target_remote, ))
self.state.store(target_remote.ip_s, 1)
class SmtpInvalidRecipientMatcher(AbstractMatcher):
"""<class maturity="stable" type="matcher">
<summary>
Class verifying the validity of the recipient addresses in E-mails.
</summary>
<description>
<para>
This class encapsulates a VRFY/RCPT based validity checker to transparently verify the existance of
E-mail addresses. Instead of immediately sending the e-mail to the recipient SMTP server, Zorp queuries an
independent SMTP server about the existance of the recipient e-mail address.
</para>
<para>
Instances of this class can be referred to in the <parameter>recipient_matcher</parameter>
attribute of the <link linkend="python.Smtp.SmtpProxy">SmtpProxy</link> class. The SmtpProxy
will automatically reject unknown recipients even if the recipient SMTP
server would accept them.
</para>
<example>
<title>SmtpInvalidMatcher example</title>
<synopsis>Python:
class SmtpRecipientMatcherProxy(SmtpProxy):
recipient_matcher="SmtpCheckrecipient"
def config(self):
super(SmtpRecipientMatcherProxy, self).config()
MatcherPolicy(name="SmtpCheckrecipient", matcher=SmtpInvalidRecipientMatcher (server_port=25, cache_timeout=60, attempt_delivery=FALSE, force_delivery_attempt=FALSE, server_name="recipientcheck.example.com"))</synopsis>
</example>
</description>
<metainfo>
<attributes/>
</metainfo>
</class>
"""
def __init__(self, server_name, server_port=25, cache_timeout=60, attempt_delivery=FALSE, force_delivery_attempt=FALSE, sender_address='<>', bind_name=''):
"""<method maturity="stable">
<summary>
</summary>
<description>
</description>
<metainfo>
<arguments>
<argument maturity="stable">
<name>server_name</name>
<type>
<string/>
</type>
<description>
Domain name of the SMTP server that will verify the addresses.
</description>
</argument>
<argument maturity="stable">
<name>server_port</name>
<type>
<integer/>
</type>
<default>25</default>
<description>
Port of the target server.
</description>
</argument>
<argument maturity="stable">
<name>cache_timeout</name>
<type>
<integer/>
</type>
<default>60</default>
<description>
How long will the result of an address verification be retained (in seconds).
</description>
</argument>
<argument maturity="obsolete">
<name>attempt_delivery</name>
<type>
<boolean/>
</type>
<default>FALSE</default>
<description>
Obsolete, ignored.
</description>
</argument>
<argument maturity="stable">
<name>force_delivery_attempt</name>
<type>
<boolean/>
</type>
<default>FALSE</default>
<description>
Force a delivery attempt even if the autodetection code otherwise
would use VRFY. Useful if the server always returns success for VRFY.
</description>
</argument>
<argument maturity="stable">
<name>sender_address</name>
<type>
<string/>
</type>
<default>"<>"</default>
<description>
This value will be used as the mail sender for the
attempted mail delivery. Mail delivery is attempted if
the <parameter>force_delivery_attempt</parameter> is TRUE,
or the recipient server does not support the VRFY command.
</description>
</argument>
<argument maturity="stable">
<name>bind_name</name>
<type>
<string/>
</type>
<default>""</default>
<description>
Specifies the hostname to bind to before initiating the connection to the SMTP server.
</description>
</argument>
</arguments>
</metainfo>
</method>
"""
super(SmtpInvalidRecipientMatcher, self).__init__()
self.force_delivery_attempt = force_delivery_attempt
self.server_name = server_name
self.server_port = server_port
self.bind_name = bind_name
self.sender_address = sender_address
self.cache = TimedCache('smtp_valid_recipients(%s)' % server_name, cache_timeout)
def checkMatch(self, email):
"""<method internal="yes">
</method>
"""
# email is a fully qualified email address like [email protected]
try:
cached = self.cache.lookup(email)
if cached != None:
## LOG ##
# This message reports that the recipient address has been already checked and
# Zorp uses the cached information.
##
log(None, CORE_DEBUG, 6, "Cached recipient match found; email='%s', cached='%d'", (email, cached))
if cached:
return TRUE
else:
return FALSE
except KeyError:
cached = None
try:
## LOG ##
# This message reports that the recipient address has not been already checked and
# Zorp is going to check it now directly.
##
log(None, CORE_DEBUG, 6, "Recipient validity not cached, trying the direct way; email='%s'", (email))
server = SmtpProto(self.server_name, self.server_port, bind_addr=self.bind_name)
try:
(smtp_code, smtp_msg) = server.ehlo()
if smtp_code > 299:
(smtp_code, smtp_msg) = server.helo()
esmtp = FALSE
else:
esmtp = TRUE
if smtp_code > 299:
raise MatcherException, "Server refused our EHLO/HELO command."
present = FALSE
smtp_code = -1
if not self.force_delivery_attempt and (not esmtp or server.has_extn("VRFY")):
log(None, CORE_DEBUG, 6, "Trying to use VRFY to check email address validity; email='%s'", (email,))
(smtp_code, smtp_msg) = server.verify(email)
present = (smtp_code < 300)
else:
log(None, CORE_DEBUG, 6, "Attempting delivery to check email address validity; email='%s'", (email,))
(smtp_code, smtp_msg) = server.mail(self.sender_address)
if smtp_code == 250:
(smtp_code, smtp_msg) = server.rcpt(email)
present = (smtp_code < 300)
else:
## LOG ##
# This message indicates that the sender address was rejected during the recipient address
# verify check and Zorp rejects the recipient address.
##
log(None, CORE_ERROR, 3, "SMTP sender was rejected, unable to verify user existence; email='%s', server_address='%s', server_port='%d'", (email, self.server_name, self.server_port))
raise MatcherException, "Server has not accepted our sender (%s)." % self.sender_address
if present:
## LOG ##
# This message reports that the recipient address verify was successful and Zorp accepts it.
##
log(None, CORE_INFO, 5, "Server accepted recipient; email='%s'", email)
# we only cache successful lookups
self.cache.store(email, not present)
elif smtp_code != -1:
## LOG ##
# This message reports that the recipient address verify was unsuccessful and Zorp rejects it.
##
log(None, CORE_INFO, 4, "Server rejected recipient; email='%s'", email)
finally:
server.quit()
except (socket.error, smtplib.SMTPException), e:
## LOG ##
# This message indicates that an SMTP error occurred during the recipient address verify
# and Zorp rejects it.
##
log(None, CORE_ERROR, 3, "SMTP error during recipient validity checking; info='%s'", e)
raise MatcherException, "SMTP error or socket failure while checking user validity (%s)" % str(e)
# we return when we want to reject...
return not present
class SmtpInvalidRecipientMatcher(AbstractMatcher):
"""<class maturity="stable" type="matcher">
<summary>
Class verifying the validity of the recipient addresses in E-mails.
</summary>
<description>
<para>
This class encapsulates a VRFY/RCPT based validity checker to transparently verify the existance of
E-mail addresses. Instead of immediately sending the e-mail to the recipient SMTP server, Zorp queuries an
independent SMTP server about the existance of the recipient e-mail address.
</para>
<para>
Instances of this class can be referred to in the <parameter>recipient_matcher</parameter>
attribute of the <link linkend="python.Smtp.SmtpProxy">SmtpProxy</link> class. The SmtpProxy
will automatically reject unknown recipients even if the recipient SMTP
server would accept them.
</para>
<example>
<title>SmtpInvalidMatcher example</title>
<synopsis>Python:
class SmtpRecipientMatcherProxy(SmtpProxy):
recipient_matcher="SmtpCheckrecipient"
def config(self):
super(SmtpRecipientMatcherProxy, self).config()
MatcherPolicy(name="SmtpCheckrecipient", matcher=SmtpInvalidRecipientMatcher (server_port=25, cache_timeout=60, attempt_delivery=FALSE, force_delivery_attempt=FALSE, server_name="recipientcheck.example.com"))</synopsis>
</example>
</description>
<metainfo>
<attributes/>
</metainfo>
</class>
"""
def __init__(self, server_name, server_port=25, cache_timeout=60, attempt_delivery=FALSE, force_delivery_attempt=FALSE, sender_address='<>', bind_name=''):
"""<method maturity="stable">
<summary>
</summary>
<description>
</description>
<metainfo>
<arguments>
<argument maturity="stable">
<name>server_name</name>
<type>
<string/>
</type>
<description>
Domain name of the SMTP server that will verify the addresses.
</description>
</argument>
<argument maturity="stable">
<name>server_port</name>
<type>
<integer/>
</type>
<default>25</default>
<description>
Port of the target server.
</description>
</argument>
<argument maturity="stable">
<name>cache_timeout</name>
<type>
<integer/>
</type>
<default>60</default>
<description>
How long will the result of an address verification be retained (in seconds).
</description>
</argument>
<argument maturity="obsolete">
<name>attempt_delivery</name>
<type>
<boolean/>
</type>
<default>FALSE</default>
<description>
Obsolete, ignored.
</description>
</argument>
<argument maturity="stable">
<name>force_delivery_attempt</name>
<type>
<boolean/>
</type>
<default>FALSE</default>
<description>
Force a delivery attempt even if the autodetection code otherwise
would use VRFY. Useful if the server always returns success for VRFY.
</description>
</argument>
<argument maturity="stable">
<name>sender_address</name>
<type>
<string/>
</type>
<default>"<>"</default>
<description>
This value will be used as the mail sender for the
attempted mail delivery. Mail delivery is attempted if
the <parameter>force_delivery_attempt</parameter> is TRUE,
or the recipient server does not support the VRFY command.
</description>
</argument>
<argument maturity="stable">
<name>bind_name</name>
<type>
<string/>
</type>
<default>""</default>
<description>
Specifies the hostname to bind to before initiating the connection to the SMTP server.
</description>
</argument>
</arguments>
</metainfo>
</method>
"""
super(SmtpInvalidRecipientMatcher, self).__init__()
self.force_delivery_attempt = force_delivery_attempt
self.server_name = server_name
self.server_port = server_port
self.bind_name = bind_name
self.sender_address = sender_address
self.cache = TimedCache('smtp_valid_recipients(%s)' % server_name, cache_timeout)
def checkMatch(self, email):
"""<method internal="yes">
</method>
"""
# email is a fully qualified email address like [email protected]
try:
cached = self.cache.lookup(email)
if cached != None:
## LOG ##
# This message reports that the recipient address has been already checked and
# Zorp uses the cached information.
##
log(None, CORE_DEBUG, 6, "Cached recipient match found; email='%s', cached='%d'", (email, cached))
if cached:
return TRUE
else:
return FALSE
except KeyError:
cached = None
try:
## LOG ##
# This message reports that the recipient address has not been already checked and
# Zorp is going to check it now directly.
##
log(None, CORE_DEBUG, 6, "Recipient validity not cached, trying the direct way; email='%s'", (email))
server = SmtpProto(self.server_name, self.server_port, bind_addr=self.bind_name)
try:
(smtp_code, smtp_msg) = server.ehlo()
if smtp_code > 299:
(smtp_code, smtp_msg) = server.helo()
esmtp = FALSE
else:
esmtp = TRUE
if smtp_code > 299:
raise MatcherException, "Server refused our EHLO/HELO command."
present = FALSE
smtp_code = -1
if not self.force_delivery_attempt and (not esmtp or server.has_extn("VRFY")):
log(None, CORE_DEBUG, 6, "Trying to use VRFY to check email address validity; email='%s'", (email,))
(smtp_code, smtp_msg) = server.verify(email)
present = (smtp_code < 300)
else:
log(None, CORE_DEBUG, 6, "Attempting delivery to check email address validity; email='%s'", (email,))
(smtp_code, smtp_msg) = server.mail(self.sender_address)
if smtp_code == 250:
(smtp_code, smtp_msg) = server.rcpt(email)
present = (smtp_code < 300)
else:
## LOG ##
# This message indicates that the sender address was rejected during the recipient address
# verify check and Zorp rejects the recipient address.
##
log(None, CORE_ERROR, 3, "SMTP sender was rejected, unable to verify user existence; email='%s', server_address='%s', server_port='%d'", (email, self.server_name, self.server_port))
raise MatcherException, "Server has not accepted our sender (%s)." % self.sender_address
if present:
## LOG ##
# This message reports that the recipient address verify was successful and Zorp accepts it.
##
log(None, CORE_INFO, 5, "Server accepted recipient; email='%s'", email)
# we only cache successful lookups
self.cache.store(email, not present)
elif smtp_code != -1:
## LOG ##
# This message reports that the recipient address verify was unsuccessful and Zorp rejects it.
##
log(None, CORE_INFO, 4, "Server rejected recipient; email='%s'", email)
finally:
server.quit()
except (socket.error, smtplib.SMTPException), e:
## LOG ##
# This message indicates that an SMTP error occurred during the recipient address verify
# and Zorp rejects it.
##
log(None, CORE_ERROR, 3, "SMTP error during recipient validity checking; info='%s'", e)
raise MatcherException, "SMTP error or socket failure while checking user validity (%s)" % str(e)
# we return when we want to reject...
return not present
class StateBasedChainer(MultiTargetChainer):
"""<class maturity="stable" abstract="yes">
<summary>
Class encapsulating connection establishment with multiple
target addresses and keeping down state between connects.
</summary>
<description>
<para>
This class encapsulates a real TCP/IP connection
establishment, and is used when a top-level proxy wants to
perform chaining. In addition to ConnectChainer, this class
adds the capability to perform stateful, load balance
server connections among a set of IP addresses.
</para>
<note>
<para>Both the <link linkend="python.Chainer.FailoverChainer">FailoverChainer</link>
and <link linkend="python.Chainer.RoundRobinChainer">RoundRobinChainer</link>
classes are derived from StateBasedChainer.</para>
</note>
</description>
<metainfo>
<attributes>
<attribute internal="yes">
<name>state</name>
<type></type>
<description>Down state of target hosts.
</description>
</attribute>
</attributes>
</metainfo>
</class>
"""
def __init__(self, protocol=ZD_PROTO_AUTO, timeout_connect=None, timeout_state=None):
"""<method maturity="stable">
<summary>
Constructor to initialize a StateBasedChainer instance.
</summary>
<description>
<para>
This constructor initializes a StateBasedChainer class by
filling arguments with appropriate values and calling the
inherited constructor.
</para>
</description>
<metainfo>
<arguments>
<argument maturity="stable">
<name>protocol</name>
<type>
<link id="zorp.proto.id"/>
</type>
<default>ZD_PROTO_AUTO</default>
<description>
Optional, specifies connection protocol (<parameter>
ZD_PROTO_TCP</parameter> or <parameter>ZD_PROTO_UDP
</parameter>), when not specified it
defaults to the same protocol used on the
client side.
</description>
</argument>
<argument>
<name>timeout_connect</name>
<type>
<integer/>
</type>
<default>30000</default>
<description>
Specifies connection timeout to be used when
connecting to the target server.
</description>
</argument>
<argument>
<name>timeout_state</name>
<type>
<integer/>
</type>
<default>60000</default>
<description>
The down state of remote hosts is kept for this interval in miliseconds.
</description>
</argument>
</arguments>
</metainfo>
</method>
"""
MultiTargetChainer.__init__(self, protocol, timeout_connect)
if not timeout_state:
timeout_state = 60000
self.state = TimedCache('chainer-state', int((timeout_state + 999) / 1000), update_stamp=FALSE)
def getNextTarget(self, session):
"""<method internal="yes">
</method>
"""
while 1:
(target_local, target_remote) = MultiTargetChainer.getNextTarget(self, session)
if not target_remote:
# we enumerated all targets
try:
session.chainer_targets_enumerated = session.chainer_targets_enumerated + 1
except AttributeError:
session.chainer_targets_enumerated = 1
if not self.state or session.chainer_targets_enumerated == 2:
# we enumerated all our targets twice, once
# with state held, and then all state
# cleared, we were not successful, terminate
# target iteration
log(None, CORE_MESSAGE, 4, "All destinations are down for two full iterations, giving up;")
return (None, None)
## LOG ##
# This message reports that the remote end is down and Zorp stores the
# down state of the remote end, so Zorp wont try to connect to it within the
# timeout latter.
##
log(None, CORE_MESSAGE, 4, "All destinations are down, clearing cache and trying again;")
# we enumerated all targets, and all of them were
# down, clear our state and try once more
self.state.clear()
self.restart(session)
continue
is_host_down = self.state.lookup(target_remote.ip_s)
if not is_host_down:
return (target_local, target_remote)
else:
## LOG ##
# This message reports that the remote end is down, but Zorp does not store the
# down state of the remote end, so Zorp will try to connect to it next time.
##
log(session.session_id, CORE_MESSAGE, 4, "Destination is down, skipping; remote='%s'", (target_remote,))
def disableTarget(self, session, target_local, target_remote):
"""<method internal="yes">
</method>
"""
## LOG ##
# This message reports that the remote end is down and Zorp stores the
# down state of the remote end, so Zorp wont try to connect to it within the
# timeout latter.
##
log(session.session_id, CORE_MESSAGE, 4, "Destination is down, keeping state; remote='%s'", (target_remote,))
self.state.store(target_remote.ip_s, 1)
