This part of the code is not documented and had escaped
testing. Files: util/ip_match.c, util/ip_match.in,
util/ip_match.ref.
+
+20121230
+
+ Bugfix (omission in feature 20111106): the postconf(1)
+ master.cf options parser didn't support "clusters" of
+ command-line option letters. File: postconf/postconf_master.c,
+ postconf/test40.ref.
+
+20130131
+
+ Bugfix: the local(8) delivery agent dereferenced a null
+ pointer while delivering to null command (for example, "|"
+ in a .forward file). Reported by Gilles Chehade.
+
+20130203
+
+ Bugfix: the undocumented OpenSSL X509_pubkey_digest()
+ function is unsuitable for computing certificate PUBLIC KEY
+ fingerprints. Postfix now provides a correct procedure
+ that accounts for the algorithm and parameters in addition
+ to the key data. Specify "tls_legacy_public_key_fingerprints
+ = yes" if you need backwards compatibility. Fix by Victor
+ Duchovni, BC added by Wietse. Files: tls/tls_verify.c,
+ tls/tls_misc.c, proto/TLS_README.html, global/mail_params.h.
+
+ Bugfix: the 20121010 fix for tls_misc.c was documented but
+ not included.
/etc/postfix/relay_clientcerts:
D7:04:2F:A7:0B:8C:A5:21:FA:31:77:E1:41:8A:EE:80 lutzpc.at.home
+To extract the public key fingerprint from an X.509 certificate, you need to
+extract the public key from the certificate and compute the appropriate digest
+of its DER (ASN.1) encoding. With OpenSSL the "-pubkey" option of the "x509"
+command extracts the public key always in "PEM" format. We pipe the result to
+another OpenSSL command that converts the key to DER and then to the "dgst"
+command to compute the fingerprint.
+
+The actual command to transform the key to DER format depends on the version of
+OpenSSL used. With OpenSSL 1.0.0 and later, the "pkey" command supports all key
+types. With OpenSSL 0.9.8 and earlier, the key type is always RSA (nobody uses
+DSA, and EC keys are not fully supported by 0.9.8), so the "rsa" command is
+used.
+
+ # OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+ $ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+ (stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+
+ # OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+ $ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+ (stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+
+Note: Postfix 2.9.0-2.9.5 computed the public key fingerprint incorrectly. To
+use public-key fingerprints, upgrade to Postfix 2.9.6 or later.
+
S\bSe\ber\brv\bve\ber\br-\b-s\bsi\bid\bde\be c\bci\bip\bph\bhe\ber\br c\bco\bon\bnt\btr\bro\bol\bls\bs
The Postfix SMTP server supports 5 distinct cipher security levels as specified
match=3D:95:34:51:24:66:33:B9:D2:40:99:C0:C1:17:0B:D1
match=EC:3B:2D:B0:5B:B1:FB:6D:20:A3:9D:72:F6:8D:12:35
+To extract the public key fingerprint from an X.509 certificate, you need to
+extract the public key from the certificate and compute the appropriate digest
+of its DER (ASN.1) encoding. With OpenSSL the "-pubkey" option of the "x509"
+command extracts the public key always in "PEM" format. We pipe the result to
+another OpenSSL command that converts the key to DER and then to the "dgst"
+command to compute the fingerprint.
+
+The actual command to transform the key to DER format depends on the version of
+OpenSSL used. With OpenSSL 1.0.0 and later, the "pkey" command supports all key
+types. With OpenSSL 0.9.8 and earlier, the key type is always RSA (nobody uses
+DSA, and EC keys are not fully supported by 0.9.8), so the "rsa" command is
+used.
+
+ # OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+ $ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+ (stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+
+ # OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+ $ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+ (stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+
+Note: Postfix 2.9.0-2.9.5 computed the public key fingerprint incorrectly. To
+use public-key fingerprints, upgrade to Postfix 2.9.6 or later.
+
M\bMa\ban\bnd\bda\bat\bto\bor\bry\by s\bse\ber\brv\bve\ber\br c\bce\ber\brt\bti\bif\bfi\bic\bca\bat\bte\be v\bve\ber\bri\bif\bfi\bic\bca\bat\bti\bio\bon\bn
At the "verify" TLS security level, messages are sent only over TLS encrypted
If you upgrade from Postfix 2.7 or earlier, read RELEASE_NOTES-2.8
before proceeding.
+Major changes with Postfix 2.9.6
+--------------------------------
+
+Thanks to OpenSSL documentation, the Postfix 2.9.0..2.9.5 SMTP
+client and server computed incorrect TLS certificate PUBLIC-KEY
+fingerprints. Support for certificate PUBLIC-KEY finger prints
+was introduced with Postfix 2.9; there is no known problem with the
+certificate fingerprint algorithms available since Postfix 2.2.
+
+Certificate PUBLIC-KEY finger prints may be used in the Postfix
+SMTP server (with "check_ccert_access") and in the Postfix SMTP
+client (with the "fingerprint" security level).
+
+Specify "tls_legacy_public_key_fingerprints = yes" temporarily,
+pending a migration from configuration files with incorrect Postfix
+2.9.0..2.9.5 certificate PUBLIC-KEY finger prints, to the correct
+fingerprints used by Postfix 2.9.6 and later.
+
+To compute the correct PUBLIC-KEY finger prints:
+
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey | \
+ openssl pkey -pubin -outform DER | \
+ openssl dgst -sha1 -c
+
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey | \
+ openssl rsa -pubin -outform DER | \
+ openssl dgst -md5 -c
+
Major changes with Postfix 2.9.2
--------------------------------
</pre>
</blockquote>
+<p> To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint. </p>
+
+<p> The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used. </p>
+<blockquote>
+<pre>
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+</pre>
+</blockquote>
+<p> Note: Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
+
<h3><a name="server_cipher">Server-side cipher controls</a> </h3>
<p> The Postfix SMTP server supports 5 distinct cipher security levels
not checked. Instead, the <a href="postconf.5.html#smtp_tls_fingerprint_cert_match">smtp_tls_fingerprint_cert_match</a> parameter
or the "match" attribute in the <a href="#client_tls_policy">policy</a>
table lists the remote SMTP server certificate fingerprint or
-public key fingerprint (Postfix 2.9 and later).
+public key fingerprint (Postfix 2.9 and later). </p>
<p> If certificate fingerprints are exchanged securely, this is the
strongest, and least scalable security level. The administrator needs
</pre>
</blockquote>
+<p> To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint. </p>
+
+<p> The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used. </p>
+<blockquote>
+<pre>
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+</pre>
+</blockquote>
+<p> Note: Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
+
<h4><a name="client_tls_verify"> Mandatory server certificate verification </a> </h4>
<p> At the "verify" TLS security level, messages are sent only over
an appropriate <a href="access.5.html">access(5)</a> policy for each client.
See <a href="RESTRICTION_CLASS_README.html">RESTRICTION_CLASS_README</a>.</p>
+<p> <b>Note:</b> Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
+
<p>This feature is available with Postfix version 2.2.</p>
</pre>
</blockquote>
-<p> Public key fingerprints are more difficult to extract, however,
-the SHA-1 public key fingerprint is often present as the value of the
-"Subject Key Identifier" extension in X.509v3 certificates. The Postfix
-SMTP server and client log the peer certificate fingerprint and public
-key fingerprint when TLS loglevel is 1 or higher. </p>
+<p> To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint. </p>
+
+<p> The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used. </p>
+<blockquote>
+<pre>
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+</pre>
+</blockquote>
+
+<blockquote>
+<pre>
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+</pre>
+</blockquote>
+
+<p> The Postfix SMTP server and client log the peer (leaf) certificate
+fingerprint and public key fingerprint when TLS loglevel is 1 or
+higher. </p>
+
+<p> <b>Note:</b> Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
<p> This feature is available in Postfix 2.5 and later. </p>
</pre>
</blockquote>
-<p> Public key fingerprints are more difficult to extract, however,
-the SHA-1 public key fingerprint is often present as the value of the
-"Subject Key Identifier" extension in X.509v3 certificates. The Postfix
-SMTP server and client log the peer certificate fingerprint and public
-key fingerprint when TLS loglevel is 1 or higher. </p>
+<p> To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint. </p>
+
+<p> The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used. </p>
+<blockquote>
+<pre>
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+</pre>
+</blockquote>
+
+<blockquote>
+<pre>
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+</pre>
+</blockquote>
+
+<p> The Postfix SMTP server and client log the peer (leaf) certificate
+fingerprint and public key fingerprint when TLS loglevel is 1 or
+higher. </p>
+
+<p> <b>Note:</b> Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
<p> Example: client-certificate access table, with sha1 fingerprints: </p>
<p> This feature is available in Postfix 2.3 and later. </p>
+</DD>
+
+<DT><b><a name="tls_legacy_public_key_fingerprints">tls_legacy_public_key_fingerprints</a>
+(default: no)</b></DT><DD>
+
+<p> A temporary migration aid for sites that use certificate
+<i>public-key</i> fingerprints with Postfix 2.9.0..2.9.5, which use
+an incorrect algorithm. This parameter has no effect on the certificate
+fingerprint support that is available since Postfix 2.2. </p>
+
+<p> Specify "<a href="postconf.5.html#tls_legacy_public_key_fingerprint">tls_legacy_public_key_fingerprints</a> = yes" temporarily,
+pending a migration from configuration files with incorrect Postfix
+2.9.0..2.9.5 certificate public-key finger prints, to the correct
+fingerprints used by Postfix 2.9.6 and later. To compute the correct
+certificate public-key fingerprints, see <a href="TLS_README.html">TLS_README</a>. </p>
+
+<p> This feature is available in Postfix 2.9.6 and later. </p>
+
+
</DD>
<DT><b><a name="tls_low_cipherlist">tls_low_cipherlist</a>
an appropriate \fBaccess\fR(5) policy for each client.
See RESTRICTION_CLASS_README.
.PP
+\fBNote:\fR Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later.
+.PP
This feature is available with Postfix version 2.2.
.SH relay_destination_concurrency_limit (default: $default_destination_concurrency_limit)
The maximal number of parallel deliveries to the same destination
.ft R
.in -4
.PP
-Public key fingerprints are more difficult to extract, however,
-the SHA-1 public key fingerprint is often present as the value of the
-"Subject Key Identifier" extension in X.509v3 certificates. The Postfix
-SMTP server and client log the peer certificate fingerprint and public
-key fingerprint when TLS loglevel is 1 or higher.
+To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint.
+.PP
+The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used.
+.sp
+.in +4
+.nf
+.na
+.ft C
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+.fi
+.ad
+.ft R
+.in -4
+.sp
+.in +4
+.nf
+.na
+.ft C
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+.fi
+.ad
+.ft R
+.in -4
+.PP
+The Postfix SMTP server and client log the peer (leaf) certificate
+fingerprint and public key fingerprint when TLS loglevel is 1 or
+higher.
+.PP
+\fBNote:\fR Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later.
.PP
This feature is available in Postfix 2.5 and later.
.SH smtp_tls_key_file (default: $smtp_tls_cert_file)
.ft R
.in -4
.PP
-Public key fingerprints are more difficult to extract, however,
-the SHA-1 public key fingerprint is often present as the value of the
-"Subject Key Identifier" extension in X.509v3 certificates. The Postfix
-SMTP server and client log the peer certificate fingerprint and public
-key fingerprint when TLS loglevel is 1 or higher.
+To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint.
+.PP
+The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used.
+.sp
+.in +4
+.nf
+.na
+.ft C
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+.fi
+.ad
+.ft R
+.in -4
+.sp
+.in +4
+.nf
+.na
+.ft C
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+.fi
+.ad
+.ft R
+.in -4
+.PP
+The Postfix SMTP server and client log the peer (leaf) certificate
+fingerprint and public key fingerprint when TLS loglevel is 1 or
+higher.
+.PP
+\fBNote:\fR Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later.
.PP
Example: client-certificate access table, with sha1 fingerprints:
.sp
OpenSSL releases.
.PP
This feature is available in Postfix 2.3 and later.
+.SH tls_legacy_public_key_fingerprints (default: no)
+A temporary migration aid for sites that use certificate
+\fIpublic-key\fR fingerprints with Postfix 2.9.0..2.9.5, which use
+an incorrect algorithm. This parameter has no effect on the certificate
+fingerprint support that is available since Postfix 2.2.
+.PP
+Specify "tls_legacy_public_key_fingerprints = yes" temporarily,
+pending a migration from configuration files with incorrect Postfix
+2.9.0..2.9.5 certificate public-key finger prints, to the correct
+fingerprints used by Postfix 2.9.6 and later. To compute the correct
+certificate public-key fingerprints, see TLS_README.
+.PP
+This feature is available in Postfix 2.9.6 and later.
.SH tls_low_cipherlist (default: ALL:!EXPORT:+RC4:@STRENGTH)
The OpenSSL cipherlist for "LOW" or higher grade ciphers. This defines
the meaning of the "low" setting in smtpd_tls_mandatory_ciphers,
s;\btls_preempt_cipherlist\b;<a href="postconf.5.html#tls_preempt_cipherlist">$&</a>;g;
s;\btls_disable_workarounds\b;<a href="postconf.5.html#tls_disable_workarounds">$&</a>;g;
s;\btls_append_default_CA\b;<a href="postconf.5.html#tls_append_default_CA">$&</a>;g;
+ s;\btls_legacy_public_key_fingerprints\b;<a href="postconf.5.html#tls_legacy_public_key_fingerprint">$&</a>;g;
s;\bfrozen_delivered_to\b;<a href="postconf.5.html#frozen_delivered_to">$&</a>;g;
s;\breset_owner_alias\b;<a href="postconf.5.html#reset_owner_alias">$&</a>;g;
</pre>
</blockquote>
+<p> To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint. </p>
+
+<p> The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used. </p>
+<blockquote>
+<pre>
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+</pre>
+</blockquote>
+<p> Note: Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
+
<h3><a name="server_cipher">Server-side cipher controls</a> </h3>
<p> The Postfix SMTP server supports 5 distinct cipher security levels
not checked. Instead, the smtp_tls_fingerprint_cert_match parameter
or the "match" attribute in the <a href="#client_tls_policy">policy</a>
table lists the remote SMTP server certificate fingerprint or
-public key fingerprint (Postfix 2.9 and later).
+public key fingerprint (Postfix 2.9 and later). </p>
<p> If certificate fingerprints are exchanged securely, this is the
strongest, and least scalable security level. The administrator needs
</pre>
</blockquote>
+<p> To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint. </p>
+
+<p> The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used. </p>
+<blockquote>
+<pre>
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+</pre>
+</blockquote>
+<p> Note: Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
+
<h4><a name="client_tls_verify"> Mandatory server certificate verification </a> </h4>
<p> At the "verify" TLS security level, messages are sent only over
an appropriate access(5) policy for each client.
See RESTRICTION_CLASS_README.</p>
+<p> <b>Note:</b> Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
+
<p>This feature is available with Postfix version 2.2.</p>
%PARAM smtpd_tls_cipherlist
</pre>
</blockquote>
-<p> Public key fingerprints are more difficult to extract, however,
-the SHA-1 public key fingerprint is often present as the value of the
-"Subject Key Identifier" extension in X.509v3 certificates. The Postfix
-SMTP server and client log the peer certificate fingerprint and public
-key fingerprint when TLS loglevel is 1 or higher. </p>
+<p> To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint. </p>
+
+<p> The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used. </p>
+<blockquote>
+<pre>
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+</pre>
+</blockquote>
+
+<blockquote>
+<pre>
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+</pre>
+</blockquote>
+
+<p> The Postfix SMTP server and client log the peer (leaf) certificate
+fingerprint and public key fingerprint when TLS loglevel is 1 or
+higher. </p>
+
+<p> <b>Note:</b> Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
<p> This feature is available in Postfix 2.5 and later. </p>
</pre>
</blockquote>
-<p> Public key fingerprints are more difficult to extract, however,
-the SHA-1 public key fingerprint is often present as the value of the
-"Subject Key Identifier" extension in X.509v3 certificates. The Postfix
-SMTP server and client log the peer certificate fingerprint and public
-key fingerprint when TLS loglevel is 1 or higher. </p>
+<p> To extract the public key fingerprint from an X.509 certificate,
+you need to extract the public key from the certificate and compute
+the appropriate digest of its DER (ASN.1) encoding. With OpenSSL
+the "-pubkey" option of the "x509" command extracts the public
+key always in "PEM" format. We pipe the result to another OpenSSL
+command that converts the key to DER and then to the "dgst" command
+to compute the fingerprint. </p>
+
+<p> The actual command to transform the key to DER format depends
+on the version of OpenSSL used. With OpenSSL 1.0.0 and later, the
+"pkey" command supports all key types. With OpenSSL 0.9.8 and
+earlier, the key type is always RSA (nobody uses DSA, and EC
+keys are not fully supported by 0.9.8), so the "rsa" command is
+used. </p>
+<blockquote>
+<pre>
+# OpenSSL 1.0 with all certificates and SHA-1 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl pkey -pubin -outform DER |
+ openssl dgst -sha1 -c
+(stdin)= 64:3f:1f:f6:e5:1e:d4:2a:56:8b:fc:09:1a:61:98:b5:bc:7c:60:58
+</pre>
+</blockquote>
+
+<blockquote>
+<pre>
+# OpenSSL 0.9.8 with RSA certificates and MD5 fingerprints.
+$ openssl x509 -in cert.pem -noout -pubkey |
+ openssl rsa -pubin -outform DER |
+ openssl dgst -md5 -c
+(stdin)= f4:62:60:f6:12:8f:d5:8d:28:4d:13:a7:db:b2:ff:50
+</pre>
+</blockquote>
+
+<p> The Postfix SMTP server and client log the peer (leaf) certificate
+fingerprint and public key fingerprint when TLS loglevel is 1 or
+higher. </p>
+
+<p> <b>Note:</b> Postfix 2.9.0–2.9.5 computed the public key
+fingerprint incorrectly. To use public-key fingerprints, upgrade
+to Postfix 2.9.6 or later. </p>
<p> Example: client-certificate access table, with sha1 fingerprints: </p>
<p> This feature is available in Postfix 2.8 and later. </p>
+%PARAM tls_legacy_public_key_fingerprints no
+
+<p> A temporary migration aid for sites that use certificate
+<i>public-key</i> fingerprints with Postfix 2.9.0..2.9.5, which use
+an incorrect algorithm. This parameter has no effect on the certificate
+fingerprint support that is available since Postfix 2.2. </p>
+
+<p> Specify "tls_legacy_public_key_fingerprints = yes" temporarily,
+pending a migration from configuration files with incorrect Postfix
+2.9.0..2.9.5 certificate public-key finger prints, to the correct
+fingerprints used by Postfix 2.9.6 and later. To compute the correct
+certificate public-key fingerprints, see TLS_README. </p>
+
+<p> This feature is available in Postfix 2.9.6 and later. </p>
+
%PARAM tlsproxy_watchdog_timeout 10s
<p> How much time a tlsproxy(8) process may take to process local
#define DEF_TLS_BUG_TWEAKS TLS_BUG_TWEAKS
extern char *var_tls_bug_tweaks;
+#define VAR_TLS_BC_PKEY_FPRINT "tls_legacy_public_key_fingerprints"
+#define DEF_TLS_BC_PKEY_FPRINT 0
+extern bool var_tls_bc_pkey_fprint;
+
/*
* Sendmail-style mail filter support.
*/
* Patches change both the patchlevel and the release date. Snapshots have no
* patchlevel; they change the release date only.
*/
-#define MAIL_RELEASE_DATE "20121213"
-#define MAIL_VERSION_NUMBER "2.9.5"
+#define MAIL_RELEASE_DATE "20130203"
+#define MAIL_VERSION_NUMBER "2.9.6"
#ifdef SNAPSHOT
# define MAIL_VERSION_DATE "-" MAIL_RELEASE_DATE
tests: test1 test2 test3 test4 test5 test6 test7 test8 test9 test10 test11 \
test12 test13 test14 test15 test16 test17 test18 test19 test20 test21 \
- test22 test23 test24 test25 test26 test27 test28 test29 test30
+ test22 test23 test24 test25 test26 test27 test28 test29 test30 test40
root_tests:
diff test30.ref test30.tmp
rm -f main.cf master.cf test30.tmp
+test40: $(PROG) test40.ref
+ rm -f main.cf master.cf
+ touch main.cf master.cf
+ echo foo unix - n n - 0 other >> master.cf
+ echo ' -voaaa=bbb' >> master.cf
+ echo ' -vo ccc=$$aaa' >> master.cf
+ echo ' -v -oddd=$$ccc' >> master.cf
+ ./$(PROG) -Mfc . unix >test40.tmp 2>&1
+ diff test40.ref test40.tmp
+ rm -f main.cf master.cf test40.tmp
+
printfck: $(OBJS) $(PROG)
rm -rf printfck
mkdir printfck
{
int field;
char *arg;
+ char *cp;
+ char *junk;
/*
* Normalize options to simplify later processing.
arg = argv->argv[field];
if (arg[0] != '-' || strcmp(arg, "--") == 0)
break;
+ for (cp = arg + 1; *cp; cp++) {
+ if (*cp == 'o' && cp > arg + 1) {
+ /* Split "-stuffo" into "-stuff" and "-o". */
+ junk = concatenate("-", cp, (char *) 0);
+ argv_insert_one(argv, field + 1, junk);
+ myfree(junk);
+ *cp = 0;
+ break;
+ }
+ }
if (strncmp(arg, "-o", 2) == 0) {
if (arg[2] != 0) {
/* Split "-oname=value" into "-o" "name=value". */
--- /dev/null
+foo unix - n n - 0 other -v
+ -o aaa=bbb -v
+ -o ccc=$aaa -v
+ -o ddd=$ccc
tls_stream.o: tls.h
tls_stream.o: tls_stream.c
tls_verify.o: ../../include/argv.h
+tls_verify.o: ../../include/mail_params.h
tls_verify.o: ../../include/msg.h
tls_verify.o: ../../include/mymalloc.h
tls_verify.o: ../../include/name_code.h
/* int var_tls_daemon_rand_bytes;
/* bool var_tls_append_def_CA;
/* bool var_tls_preempt_clist;
+/* bool var_tls_bc_pkey_fprint;
/*
/* TLS_APPL_STATE *tls_alloc_app_context(ssl_ctx, log_mask)
/* SSL_CTX *ssl_ctx;
char *var_tls_eecdh_ultra;
bool var_tls_append_def_CA;
char *var_tls_bug_tweaks;
+bool var_tls_bc_pkey_fprint;
#ifdef VAR_TLS_PREEMPT_CLIST
bool var_tls_preempt_clist;
else
include |= code =
name_code(protocol_table, NAME_CODE_FLAG_NONE, tok);
- if (code == TLS_PROTOCOL_INVALID)
+ if (code == TLS_PROTOCOL_INVALID) {
+ myfree(save);
return TLS_PROTOCOL_INVALID;
+ }
}
myfree(save);
};
static const CONFIG_BOOL_TABLE bool_table[] = {
VAR_TLS_APPEND_DEF_CA, DEF_TLS_APPEND_DEF_CA, &var_tls_append_def_CA,
+ VAR_TLS_BC_PKEY_FPRINT, DEF_TLS_BC_PKEY_FPRINT, &var_tls_bc_pkey_fprint,
#if OPENSSL_VERSION_NUMBER >= 0x0090700fL /* OpenSSL 0.9.7 and later */
VAR_TLS_PREEMPT_CLIST, DEF_TLS_PREEMPT_CLIST, &var_tls_preempt_clist,
#endif
/* X509 *peercert;
/* const char *dgst;
/*
+/* char *tls_pkey_fprint(peercert, dgst)
+/* X509 *peercert;
+/* const char *dgst;
+/*
/* int tls_verify_certificate_callback(ok, ctx)
/* int ok;
/* X509_STORE_CTX *ctx;
/* value is dynamically allocated with mymalloc(), and the caller
/* must eventually free it with myfree().
/*
+/* tls_pkey_fprint() returns a public-key fingerprint; in all
+/* other respects the function behaves as tls_fingerprint().
+/* The var_tls_bc_pkey_fprint variable enables an incorrect
+/* algorithm that was used in Postfix versions 2.9.[0-5].
+/*
/* tls_verify_callback() is called several times (directly or
/* indirectly) from crypto/x509/x509_vfy.c. It is called as
/* a final check, and if it returns "0", the handshake is
#include <mymalloc.h>
#include <stringops.h>
+/* Global library. */
+
+#include <mail_params.h>
+
/* TLS library. */
#define TLS_INTERNAL
return (cn ? cn : mystrdup(""));
}
-typedef int (*x509_dgst_cb) (const X509 *, const EVP_MD *, unsigned char *, unsigned int *);
-
-/* tls_fprint - extract cert or pkey fingerprint from certificate */
+/* tls_fprint - compute and encode digest of DER-encoded object */
-static char *tls_fprint(X509 *peercert, x509_dgst_cb x509_dgst,
- const char *dgst)
+static char *tls_fprint(const char *buf, int len, const char *dgst)
{
- const char *myname = "tls_fingerprint";
+ const char *myname = "tls_fprint";
+ EVP_MD_CTX *mdctx;
const EVP_MD *md_alg;
unsigned char md_buf[EVP_MAX_MD_SIZE];
unsigned int md_len;
if ((md_alg = EVP_get_digestbyname(dgst)) == 0)
msg_panic("%s: digest algorithm \"%s\" not found", myname, dgst);
- /* Fails when serialization to ASN.1 runs out of memory */
- if (x509_dgst(peercert, md_alg, md_buf, &md_len) == 0)
- msg_fatal("%s: error computing certificate %s digest (out of memory?)",
- myname, dgst);
+ mdctx = EVP_MD_CTX_create();
+ if (EVP_DigestInit_ex(mdctx, md_alg, NULL) == 0
+ || EVP_DigestUpdate(mdctx, buf, len) == 0
+ || EVP_DigestFinal_ex(mdctx, md_buf, &md_len) == 0)
+ msg_fatal("%s: error computing %s message digest", myname, dgst);
+ EVP_MD_CTX_destroy(mdctx);
/* Check for OpenSSL contract violation */
if (md_len > EVP_MAX_MD_SIZE || md_len >= INT_MAX / 3)
char *tls_fingerprint(X509 *peercert, const char *dgst)
{
- return (tls_fprint(peercert, X509_digest, dgst));
+ int len;
+ char *buf;
+ char *buf2;
+ char *result;
+
+ len = i2d_X509(peercert, NULL);
+ buf2 = buf = mymalloc(len);
+ i2d_X509(peercert, (unsigned char **)&buf2);
+ if (buf2 - buf != len)
+ msg_panic("i2d_X509 invalid result length");
+
+ result = tls_fprint(buf, len, dgst);
+ myfree(buf);
+
+ return (result);
}
/* tls_pkey_fprint - extract public key fingerprint from certificate */
char *tls_pkey_fprint(X509 *peercert, const char *dgst)
{
- return (tls_fprint(peercert, X509_pubkey_digest, dgst));
+ if (var_tls_bc_pkey_fprint) {
+ const char *myname = "tls_pkey_fprint";
+ ASN1_BIT_STRING *key;
+ char *result;
+
+ key = X509_get0_pubkey_bitstr(peercert);
+ if (key == 0)
+ msg_fatal("%s: error extracting legacy public-key fingerprint: %m",
+ myname);
+
+ result = tls_fprint((char *) key->data, key->length, dgst);
+ return (result);
+ } else {
+ int len;
+ char *buf;
+ char *buf2;
+ char *result;
+
+ len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(peercert), NULL);
+ buf2 = buf = mymalloc(len);
+ i2d_X509_PUBKEY(X509_get_X509_PUBKEY(peercert), (unsigned char **) &buf2);
+ if (buf2 - buf != len)
+ msg_panic("i2d_X509_PUBKEY invalid result length");
+
+ result = tls_fprint(buf, len, dgst);
+ myfree(buf);
+ return (result);
+ }
}
#endif
/*
* See if this command contains any shell magic characters.
*/
- if (command[strspn(command, ok_chars)] == 0) {
+ if (command[strspn(command, ok_chars)] == 0
+ && command[strspn(command, SPACE_TAB)] != 0) {
/*
* No shell meta characters found, so we can try to avoid the overhead