SMM:08-48
Sendmail Installation and Operation Guide
${auth_ssf}
The keylength (in bits) of the symmetric encryption algorithm used for the security layer of a
SASL mechanism.
${bodytype}
The message body type (7BIT or 8BITMIME), as determined from the envelope.
${cert_issuer}
The DN (distinguished name) of the CA (certificate authority) that signed the presented cer-
tificate (the cert issuer) (STARTTLS only).
${cert_md5}
The MD5 hash of the presented certificate (STARTTLS only).
${cert_subject}
The DN of the presented certificate (called the cert subject) (STARTTLS only).
${cipher}
The cipher suite used for the connection, e.g., EDH-DSS-DES-CBC3-SHA, EDH-RSA-DES-
CBC-SHA, DES-CBC-MD5, DES-CBC3-SHA (STARTTLS only).
${cipher_bits}
The effective keylength (in bits) of the symmetric encryption algorithm used for a TLS con-
nection.
${client_addr}
The IP address of the SMTP client. IPv6 addresses are tagged with "IPv6:" before the
address. Defined in the SMTP server only.
${client_connections}
The number of open connections in the SMTP server for the client IP address.
${client_name}
The host name of the SMTP client. This may be the client's bracketed IP address in the form
[ nnn.nnn.nnn.nnn ] for IPv4 and [ IPv6:nnnn:...:nnnn ] for IPv6 if the client's IP address is
not resolvable, or if it is resolvable but the IP address of the resolved hostname doesn't match
the original IP address. Defined in the SMTP server only. See also ${client_resolve}.
${client_port}
The port number of the SMTP client. Defined in the SMTP server only.
${client_ptr}
The result of the PTR lookup for the client IP address. Note: this is the same as
${client_name}
if and only if ${client_resolve} is OK. Defined in the SMTP server only.
${client_rate}
The number of incoming connections for the client IP address over the time interval specified
by ConnectionRateWindowSize.
${client_resolve}
Holds the result of the resolve call for ${client_name}. Possible values are:
OK resolved
successfully
FAIL permanent lookup
failure
FORGED forward lookup doesn't match reverse lookup
TEMP temporary lookup
failure
Defined in the SMTP server only. sendmail performs a hostname lookup on the IP address of
the connecting client. Next the IP addresses of that hostname are looked up. If the client IP
address does not appear in that list, then the hostname is maybe forged. This is reflected as
the value FORGED for ${client_resolve} and it also shows up in $_ as "(may be forged)".