ARC: log signing-spec errors in mainlog only, not paniclog

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

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index cf80e92f7ae747a41ee9cab42702d6de42fc5c8e..2dbe6d2d34b14112e0ad9e18f3718c2bbb87856e 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -52,7 +52,7 @@
 .set I   "    "
 
 .macro copyyear
-2017
+2018
 .endmacro
 
 . /////////////////////////////////////////////////////////////////////////////
@@ -7839,6 +7839,19 @@ ${lookup redis{set keyname ${quote_redis:objvalue plus}}}
 ${lookup redis{get keyname}}
 .endd
 
+.new
+As of release 4.91, "lightweight" support for Redis Cluster is available.
+Requires &%redis_servers%& list to contain all the servers in the cluster, all
+of which must be reachable from the running exim instance. If the cluster has
+master/slave replication, the list must contain all the master and slave
+servers.
+
+When the Redis Cluster returns a "MOVED" response to a query, exim does not
+immediately follow the redirection but treats the response as a DEFER, moving on
+to the next server in the &%redis_servers%& list until the correct server is
+reached.
+.wen
+
 .ecindex IIDfidalo1
 .ecindex IIDfidalo2
 
@@ -9141,6 +9154,7 @@ If the ACL returns defer the result is a forced-fail.  Otherwise the expansion f
 .vitem "&*${authresults{*&<&'authserv-id'&>&*}}*&"
 .cindex authentication "results header"
 .cindex headers "authentication-results:"
+.cindex authentication "expansion item"
 This item returns a string suitable for insertion as an
 &'Authentication-Results"'&
 header line.
@@ -9159,6 +9173,7 @@ Example use (as an ACL modifier):
 .code
       add_header = :at_start:${authresults {$primary_hostname}}
 .endd
+This is safe even if no authentication reselts are available.
 .wen
 
 
@@ -11580,10 +11595,15 @@ preserve some of the authentication information in the variable
 user/password authenticator configuration might preserve the user name for use
 in the routers. Note that this is not the same information that is saved in
 &$sender_host_authenticated$&.
+
 When a message is submitted locally (that is, not over a TCP connection)
 the value of &$authenticated_id$& is normally the login name of the calling
 process. However, a trusted user can override this by means of the &%-oMai%&
 command line option.
+.new
+This second case also sets up inforamtion used by the
+&$authresults$& expansion item.
+.wen
 
 .vitem &$authenticated_fail_id$&
 .cindex "authentication" "fail" "id"
@@ -11923,6 +11943,13 @@ lookup succeeds, but there is a lookup problem such as a timeout when checking
 the result, the name is not accepted, and &$host_lookup_deferred$& is set to
 &"1"&. See also &$sender_host_name$&.
 
+.new
+.cindex authentication "expansion item"
+Performing these checks sets up information used by the
+&$authresults$& expansion item.
+.wen
+
+
 .vitem &$host_lookup_failed$&
 .vindex "&$host_lookup_failed$&"
 See &$host_lookup_deferred$&.
@@ -12878,6 +12905,7 @@ is compiled with the content-scanning extension. For details, see section
 .vitem &$spf_header_comment$& &&&
        &$spf_received$& &&&
        &$spf_result$& &&&
+       &$spf_result_guessed$& &&&
        &$spf_smtp_comment$&
 These variables are only available if Exim is built with SPF support.
 For details see section &<<SECSPF>>&.
@@ -26091,6 +26119,12 @@ public name) of the authenticator driver that successfully authenticated the
 client from which the message was received. This variable is empty if there was
 no successful authentication.
 
+.new
+.cindex authentication "expansion item"
+Successful authentication sets up information used by the
+&$authresults$& expansion item.
+.wen
+
 
 
 
@@ -38890,7 +38924,8 @@ The result can either
 be a valid RSA private key in ASCII armor (.pem file), including line breaks
 .new
 .next
-with GnuTLS 3.6.0 or later, be a valid Ed25519 private key (same format as above)
+with GnuTLS 3.6.0 or OpenSSL 1.1.1 or later,
+be a valid Ed25519 private key (same format as above)
 .wen
 .next
 start with a slash, in which case it is treated as a file that contains
@@ -38902,6 +38937,21 @@ is set.
 .endlist
 
 .new
+To generate keys under OpenSSL:
+.code
+openssl genrsa -out dkim_rsa.private 2048
+openssl rsa -in dkim_rsa.private -out /dev/stdout -pubout -outform PEM
+.endd
+Take the base-64 lines from the output of the second command, concatenated,
+for the DNS TXT record.
+See section 3.6 of RFC6376 for the record specification.
+
+Under GnuTLS:
+.code
+certtool --generate-privkey --rsa --bits=2048 --password='' -8 --outfile=dkim_rsa.private
+certtool --load-privkey=dkim_rsa.private --pubkey-info
+.endd
+
 Note that RFC 8301 says:
 .code
 Signers MUST use RSA keys of at least 1024 bits for all keys.
@@ -38916,6 +38966,18 @@ As they are a recent development, users should consider dual-signing
 for some transition period.
 The "_CRYPTO_SIGN_ED25519" macro will be defined if support is present
 for EC keys.
+
+OpenSSL 1.1.1 and GnuTLS 3.6.0 can create Ed25519 private keys:
+.code
+openssl genpkey -algorithm ed25519 -out dkim_ed25519.private
+certtool --generate-privkey --key-type=ed25519 --outfile=dkim_ed25519.private
+.endd
+
+To produce the required public key value for a DNS record:
+.code
+openssl pkey -outform DER -pubout -in dkim_ed25519.private | tail -c +13 | base64
+certtool --load_privkey=dkim_ed25519.private --pubkey_info --outder | tail -c +13 | base64
+.endd
 .wen
 
 .option dkim_hash smtp string&!! sha256
@@ -38986,6 +39048,12 @@ To evaluate the signature in the ACL a large number of expansion variables
 containing the signature status and its details are set up during the
 runtime of the ACL.
 
+.new
+.cindex authentication "expansion item"
+Performing verification sets up information used by the
+&$authresults$& expansion item.
+.wen
+
 Calling the ACL only for existing signatures is not sufficient to build
 more advanced policies. For that reason, the global option
 &%dkim_verify_signers%&, and a global expansion variable
@@ -39101,7 +39169,8 @@ The key record selector string.
 .vitem &%$dkim_algo%&
 The algorithm used. One of 'rsa-sha1' or 'rsa-sha256'.
 .new
-If running under GnuTLS 3.6.0 or later, may also be 'ed25519-sha256'.
+If running under GnuTLS 3.6.0 or OpenSSL 1.1.1 or later,
+may also be 'ed25519-sha256'.
 The "_CRYPTO_SIGN_ED25519" macro will be defined if support is present
 for EC keys.
 .wen
@@ -39245,6 +39314,12 @@ There is no Exim involvement on the trasmission of messages; publishing certain
 DNS records is all that is required.
 
 For verification, an ACL condition and an expansion lookup are provided.
+.new
+.cindex authentication "expansion item"
+Performing verification sets up information used by the
+&$authresults$& expansion item.
+.wen
+
 
 .cindex SPF "ACL condition"
 .cindex ACL "spf condition"
@@ -39274,18 +39349,11 @@ its domain as well.  This should be treated like "none".
 
 .vitem &%permerror%&
 This indicates a syntax error in the SPF record of the queried domain.
-You may deny messages when this occurs. (Changed in 4.83)
+You may deny messages when this occurs.
 
 .vitem &%temperror%&
 This indicates a temporary error during all processing, including Exim's
 SPF processing.  You may defer messages when this occurs.
-(Changed in 4.83)
-
-.vitem &%err_temp%&
-Same as permerror, deprecated in 4.83, will be removed in a future release.
-
-.vitem &%err_perm%&
-Same as temperror, deprecated in 4.83, will be removed in a future release.
 .endlist
 
 You can prefix each string with an exclamation mark to  invert
@@ -39333,6 +39401,11 @@ variables:
   one of pass, fail, softfail, none, neutral, permerror or
   temperror.
 
+.vitem &$spf_result_guessed$&
+.vindex &$spf_result_guessed$&
+  This boolean is true only if a best-guess operation was used
+  and required in order to obtain a result.
+
 .vitem &$spf_smtp_comment$&
 .vindex &$spf_smtp_comment$&
   This contains a string that can be used in a SMTP response