Cisco Cisco Email Security Appliance C650 Guía Del Usuario
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Cisco IronPort AsyncOS 7.5 for Email Advanced Configuration Guide
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Chapter 6 Using Message Filters to Enforce Email Policies
Since X.509 certificates require the issuer field,
signed-certificate(“issuer”)
evaluates whether the S/MIME message contains an X.509 certificate.
Escaping in Regular Expressions
LDAP-UTF8 defines a mechanism for escaping that you can use in your regular
expressions. For a detailed discussion on escaping characters in LDAP-UTF8,
consult Lightweight Directory Access Protocol (LDAP): String Representation of
Distinguished Names, accessible from
expressions. For a detailed discussion on escaping characters in LDAP-UTF8,
consult Lightweight Directory Access Protocol (LDAP): String Representation of
Distinguished Names, accessible from
http://www.ietf.org/rfc/rfc4514.txt
.
The escaping rules for the
signed-certificate
rule’s regular expressions differ
from the escaping rules defined in LDAP-UTF8 by limiting escaping to only the
characters that require escaping. LDAP-UTF8 allows optional escaping for
characters that can be represented without escaping. For example, the following
two strings are considered correct for “Example, Inc.” using the LDAP-UTF8
escaping rules:
characters that require escaping. LDAP-UTF8 allows optional escaping for
characters that can be represented without escaping. For example, the following
two strings are considered correct for “Example, Inc.” using the LDAP-UTF8
escaping rules:
•
Example\, Inc.
•
Example\,\ Inc\.
However, the
signed-certificate
rule only matches
Example\, Inc.
The
regular expression does not allow escaping the space and period for matching
because these characters do not require escaping, even though it is permitted in
LDAP-UTF8. When creating a regular expression for the
because these characters do not require escaping, even though it is permitted in
LDAP-UTF8. When creating a regular expression for the
signed-certificate
rule, do not escape a character if it can be represented without escaping.
$CertificateSigners Action Variable
The action variable
$CertificateSigners
is a comma separated list of signers
obtained from the
subjectAltName
element of the signing certificate. Multiple
email addresses of a single signer will be included in the list with duplicates
removed.
removed.
For example, Alice signs a message with her two certificates. Bob signs the
message with his single certificate. All certificates are issued by a single corporate
authority. After the message passes the S/MIME scan, the extracted data contain
three items:
message with his single certificate. All certificates are issued by a single corporate
authority. After the message passes the S/MIME scan, the extracted data contain
three items:
[
{
'issuer': 'CN=Auth,O=Example\, Inc.',