VRFY: Permit an ACL to override the default 252 response, to support

[exim.git] / doc / doc-docbook / spec.xfpt

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 6f6ee4557282ce027ac6cadbdb2bfe88001e0902..cb913d6f1f481e5566f6f812173b17e447430636 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -10038,8 +10038,13 @@ string.
 .cindex "expansion" "base64 encoding"
 .cindex "base64 encoding" "in string expansion"
 .cindex "&%base64%& expansion item"
+.cindex certificate "base64 of DER"
 This operator converts a string into one that is base64 encoded.
 
+If the string is a single variable of type certificate,
+returns the base64 encoding of the DER form of the certificate.
+
+
 .vitem &*${base64d:*&<&'string'&>&*}*&
 .cindex "expansion" "base64 decoding"
 .cindex "base64 decoding" "in string expansion"
@@ -15426,7 +15431,7 @@ harm. This option overrides the &%pipe_as_creator%& option of the &(pipe)&
 transport driver.
 
 
-.option openssl_options main "string list" "+no_sslv2"
+.option openssl_options main "string list" "+no_sslv2 +single_dh_use"
 .cindex "OpenSSL "compatibility options"
 This option allows an administrator to adjust the SSL options applied
 by OpenSSL to connections.  It is given as a space-separated list of items,
@@ -27543,6 +27548,12 @@ Note that a client may issue more than one EHLO or HELO command in an SMTP
 session, and indeed is required to issue a new EHLO or HELO after successfully
 setting up encryption following a STARTTLS command.
 
+.new
+Note also that a deny neither forces the client to go away nor means that
+mail will be refused on the connection.  Consider checking for
+&$sender_helo_name$& being defined in a MAIL or RCPT ACL to do that.
+.wen
+
 If the command is accepted by an &%accept%& verb that has a &%message%&
 modifier, the message may not contain more than one line (it will be truncated
 at the first newline and a panic logged if it does). Such a message cannot
@@ -34035,13 +34046,20 @@ specific badly-behaved hosts that you have to live with.
 When Exim receives a VRFY or EXPN command on a TCP/IP connection, it
 runs the ACL specified by &%acl_smtp_vrfy%& or &%acl_smtp_expn%& (as
 appropriate) in order to decide whether the command should be accepted or not.
-If no ACL is defined, the command is rejected.
 
+.new
 .cindex "VRFY" "processing"
+When no ACL is defined for VRFY, or if it rejects without
+setting an explicit response code, the command is accepted
+(with a 252 SMTP response code)
+in order to support awkward clients that do a VRFY before every RCPT.
+.wen
 When VRFY is accepted, it runs exactly the same code as when Exim is
-called with the &%-bv%& option.
+called with the &%-bv%& option, and returns 250/451/550
+SMTP response codes.
 
 .cindex "EXPN" "processing"
+If no ACL for EXPN is defined, the command is rejected.
 When EXPN is accepted, a single-level expansion of the address is done.
 EXPN is treated as an &"address test"& (similar to the &%-bt%& option) rather
 than a verification (the &%-bv%& option). If an unqualified local part is given
@@ -37930,8 +37948,10 @@ linked to a domain which that entity controls.  It permits reputation to
 be tracked on a per-domain basis, rather than merely upon source IP address.
 DKIM is documented in RFC 4871.
 
-Since version 4.70, DKIM support is compiled into Exim by default. It can be
-disabled by setting DISABLE_DKIM=yes in &_Local/Makefile_&.
+.new
+DKIM support is compiled into Exim by default if TLS support is present.
+.wen
+It can be disabled by setting DISABLE_DKIM=yes in &_Local/Makefile_&.
 
 Exim's DKIM implementation allows to
 .olist