Adding upstream version 3.5.24.upstream/3.5.24upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

5 files changed, 2452 insertions, 0 deletions

diff --git a/src/posttls-finger/.indent.pro b/src/posttls-finger/.indent.pro
new file mode 120000
index 0000000..5c837ec
--- /dev/null
+++ b/src/posttls-finger/.indent.pro
@@ -0,0 +1 @@
+../../.indent.pro
\ No newline at end of file
diff --git a/src/posttls-finger/Makefile.in b/src/posttls-finger/Makefile.in
new file mode 100644
index 0000000..8855002
--- /dev/null
+++ b/src/posttls-finger/Makefile.in
@@ -0,0 +1,116 @@
+SHELL	= /bin/sh
+SRCS	= posttls-finger.c tlsmgrmem.c
+OBJS	= posttls-finger.o tlsmgrmem.o
+HDRS	= tlsmgrmem.h
+TESTSRC	= 
+DEFS	= -I. -I$(INC_DIR) -D$(SYSTYPE)
+CFLAGS	= $(DEBUG) $(OPT) $(DEFS)
+TESTPROG= 
+INC_DIR	= ../../include
+PROG	= posttls-finger
+LIBS	= ../../lib/lib$(LIB_PREFIX)tls$(LIB_SUFFIX) \
+	../../lib/lib$(LIB_PREFIX)dns$(LIB_SUFFIX) \
+	../../lib/lib$(LIB_PREFIX)global$(LIB_SUFFIX) \
+	../../lib/lib$(LIB_PREFIX)util$(LIB_SUFFIX)
+
+.c.o:;	$(CC) $(CFLAGS) -c $*.c
+
+all:	$(PROG)
+
+$(OBJS): ../../conf/makedefs.out $(HDRS)
+
+Makefile: Makefile.in
+	cat ../../conf/makedefs.out $? >$@
+
+posttls-finger: $(OBJS) $(LIBS)
+	$(CC) $(CFLAGS) $(SHLIB_RPATH) -o $@ $(OBJS) $(LIBS) $(SYSLIBS)
+
+test:	$(TESTPROG)
+
+tests:
+
+root_tests:
+
+update: ../../bin/posttls-finger
+
+../../bin/posttls-finger: posttls-finger
+	cp $? $@
+
+printfck: $(OBJS) $(PROG)
+	rm -rf printfck
+	mkdir printfck
+	sed '1,/^# do not edit/!d' Makefile >printfck/Makefile
+	set -e; for i in *.c; do printfck -f .printfck $$i >printfck/$$i; done
+	cd printfck; make "INC_DIR=../../../include" `cd ..; ls *.o`
+
+lint:
+	lint $(DEFS) $(SRCS) $(LINTFIX)
+
+clean:
+	rm -f *.o *core $(PROG) $(TESTPROG) junk
+	rm -rf printfck
+
+tidy:	clean
+
+depend: $(MAKES)
+	(sed '1,/^# do not edit/!d' Makefile.in; \
+	set -e; for i in [a-z][a-z0-9]*.c; do \
+	    $(CC) -E $(DEFS) $(INCL) $$i | grep -v '[<>]' | sed -n -e '/^# *1 *"\([^"]*\)".*/{' \
+	    -e 's//'`echo $$i|sed 's/c$$/o/'`': \1/' \
+	    -e 's/o: \.\//o: /' -e p -e '}' ; \
+	done | LANG=C sort -u) | grep -v '[.][o][:][ ][/]' >$$$$ && mv $$$$ Makefile.in
+	@$(EXPORT) make -f Makefile.in Makefile 1>&2
+
+# do not edit below this line - it is generated by 'make depend'
+posttls-finger.o: ../../include/argv.h
+posttls-finger.o: ../../include/attr.h
+posttls-finger.o: ../../include/check_arg.h
+posttls-finger.o: ../../include/chroot_uid.h
+posttls-finger.o: ../../include/clean_env.h
+posttls-finger.o: ../../include/dns.h
+posttls-finger.o: ../../include/dsn.h
+posttls-finger.o: ../../include/dsn_buf.h
+posttls-finger.o: ../../include/host_port.h
+posttls-finger.o: ../../include/htable.h
+posttls-finger.o: ../../include/inet_proto.h
+posttls-finger.o: ../../include/iostuff.h
+posttls-finger.o: ../../include/mail_conf.h
+posttls-finger.o: ../../include/mail_params.h
+posttls-finger.o: ../../include/mail_parm_split.h
+posttls-finger.o: ../../include/mail_proto.h
+posttls-finger.o: ../../include/mail_server.h
+posttls-finger.o: ../../include/midna_domain.h
+posttls-finger.o: ../../include/msg.h
+posttls-finger.o: ../../include/msg_vstream.h
+posttls-finger.o: ../../include/myaddrinfo.h
+posttls-finger.o: ../../include/mymalloc.h
+posttls-finger.o: ../../include/name_code.h
+posttls-finger.o: ../../include/name_mask.h
+posttls-finger.o: ../../include/nvtable.h
+posttls-finger.o: ../../include/sane_connect.h
+posttls-finger.o: ../../include/smtp_stream.h
+posttls-finger.o: ../../include/sock_addr.h
+posttls-finger.o: ../../include/stringops.h
+posttls-finger.o: ../../include/sys_defs.h
+posttls-finger.o: ../../include/timed_connect.h
+posttls-finger.o: ../../include/tls.h
+posttls-finger.o: ../../include/tls_proxy.h
+posttls-finger.o: ../../include/vbuf.h
+posttls-finger.o: ../../include/vstream.h
+posttls-finger.o: ../../include/vstring.h
+posttls-finger.o: ../../include/vstring_vstream.h
+posttls-finger.o: posttls-finger.c
+posttls-finger.o: tlsmgrmem.h
+tlsmgrmem.o: ../../include/argv.h
+tlsmgrmem.o: ../../include/check_arg.h
+tlsmgrmem.o: ../../include/dict.h
+tlsmgrmem.o: ../../include/htable.h
+tlsmgrmem.o: ../../include/myflock.h
+tlsmgrmem.o: ../../include/sys_defs.h
+tlsmgrmem.o: ../../include/tls_mgr.h
+tlsmgrmem.o: ../../include/tls_scache.h
+tlsmgrmem.o: ../../include/vbuf.h
+tlsmgrmem.o: ../../include/vstream.h
+tlsmgrmem.o: ../../include/vstring.h
+tlsmgrmem.o: tlsmgrmem.c
+tlsmgrmem.o: tlsmgrmem.h
diff --git a/src/posttls-finger/posttls-finger.c b/src/posttls-finger/posttls-finger.c
new file mode 100644
index 0000000..849b05d
--- /dev/null
+++ b/src/posttls-finger/posttls-finger.c
@@ -0,0 +1,2164 @@
+/*++
+/* NAME
+/*	posttls-finger 1
+/* SUMMARY
+/*	Probe the TLS properties of an ESMTP or LMTP server.
+/* SYNOPSIS
+/*	\fBposttls-finger\fR [\fIoptions\fR] [\fBinet:\fR]\fIdomain\fR[:\fIport\fR] [\fImatch ...\fR]
+/* .br
+/*	\fBposttls-finger\fR -S [\fIoptions\fR] \fBunix:\fIpathname\fR [\fImatch ...\fR]
+/* DESCRIPTION
+/*	\fBposttls-finger\fR(1) connects to the specified destination
+/*	and reports TLS-related information about the server. With SMTP, the
+/*	destination is a domainname; with LMTP it is either a domainname
+/*	prefixed with \fBinet:\fR or a pathname prefixed with \fBunix:\fR.  If
+/*	Postfix is built without TLS support, the resulting posttls-finger
+/*	program has very limited functionality, and only the \fB-a\fR, \fB-c\fR,
+/*	\fB-h\fR, \fB-o\fR, \fB-S\fR, \fB-t\fR, \fB-T\fR and \fB-v\fR options
+/*	are available.
+/*
+/*	Note: this is an unsupported test program. No attempt is made
+/*	to maintain compatibility between successive versions.
+/*
+/*	For SMTP servers that don't support ESMTP, only the greeting banner
+/*	and the negative EHLO response are reported. Otherwise, the reported
+/*	EHLO response details further server capabilities.
+/*
+/*	If TLS support is enabled when \fBposttls-finger\fR(1) is compiled, and
+/*	the server supports \fBSTARTTLS\fR, a TLS handshake is attempted.
+/*
+/*	If DNSSEC support is available, the connection TLS security level
+/*	(\fB-l\fR option) defaults to \fBdane\fR; see TLS_README for
+/*	details. Otherwise, it defaults to \fBsecure\fR.  This setting
+/*	determines the certificate matching policy.
+/*
+/*	If TLS negotiation succeeds, the TLS protocol and cipher details are
+/*	reported. The server certificate is then verified in accordance with
+/*	the policy at the chosen (or default) security level.  With public
+/*	CA-based trust, when the \fB-L\fR option includes \fBcertmatch\fR,
+/*	(true by default) name matching is performed even if the certificate
+/*	chain is not trusted.  This logs the names found in the remote SMTP
+/*	server certificate and which if any would match, were the certificate
+/*	chain trusted.
+/*
+/*	Note: \fBposttls-finger\fR(1) does not perform any table lookups, so
+/*	the TLS policy table and obsolete per-site tables are not consulted.
+/*	It does not communicate with the \fBtlsmgr\fR(8) daemon (or any other
+/*	Postfix daemons); its TLS session cache is held in private memory, and
+/*	disappears when the process exits.
+/*
+/*	With the \fB-r \fIdelay\fR option, if the server assigns a TLS
+/*	session id, the TLS session is cached. The connection is then closed
+/*	and re-opened after the specified delay, and \fBposttls-finger\fR(1)
+/*	then reports whether the cached TLS session was re-used.
+/*
+/*	When the destination is a load balancer, it may be distributing
+/*	load between multiple server caches. Typically, each server returns
+/*	its unique name in its EHLO response. If, upon reconnecting with
+/*	\fB-r\fR, a new server name is detected, another session is cached
+/*	for the new server, and the reconnect is repeated up to a maximum
+/*	number of times (default 5) that can be specified via the \fB-m\fR
+/*	option.
+/*
+/*	The choice of SMTP or LMTP (\fB-S\fR option) determines the syntax of
+/*	the destination argument. With SMTP, one can specify a service on a
+/*	non-default port as \fIhost\fR:\fIservice\fR, and disable MX (mail
+/*	exchanger) DNS lookups with [\fIhost\fR] or [\fIhost\fR]:\fIport\fR.
+/*	The [] form is required when you specify an IP address instead of a
+/*	hostname.  An IPv6 address takes the form [\fBipv6:\fIaddress\fR].
+/*	The default port for SMTP is taken from the \fBsmtp/tcp\fR entry in
+/*	/etc/services, defaulting to 25 if the entry is not found.
+/*
+/*	With LMTP, specify \fBunix:\fIpathname\fR to connect to a local server
+/*	listening on a unix-domain socket bound to the specified pathname;
+/*	otherwise, specify an optional \fBinet:\fR prefix followed by a
+/*	\fIdomain\fR and an optional port, with the same syntax as for
+/*	SMTP. The default TCP port for LMTP is 24.
+/*
+/*	Arguments:
+/* .IP "\fB-a\fR \fIfamily\fR (default: \fBany\fR)"
+/*	Address family preference: \fBipv4\fR, \fBipv6\fR or \fBany\fR.  When
+/*	using \fBany\fR, posttls-finger will randomly select one of the two as
+/*	the more preferred, and exhaust all MX preferences for the first
+/*	address family before trying any addresses for the other.
+/* .IP "\fB-A\fR \fItrust-anchor.pem\fR (default: none)"
+/*	A list of PEM trust-anchor files that overrides CAfile and CApath
+/*	trust chain verification.  Specify the option multiple times to
+/*	specify multiple files.  See the main.cf documentation for
+/*	smtp_tls_trust_anchor_file for details.
+/* .IP "\fB-c\fR"
+/*	Disable SMTP chat logging; only TLS-related information is logged.
+/* .IP "\fB-C\fR"
+/*	Print the remote SMTP server certificate trust chain in PEM format.
+/*	The issuer DN, subject DN, certificate and public key fingerprints
+/*	(see \fB-d \fImdalg\fR option below) are printed above each PEM
+/*	certificate block.  If you specify \fB-F \fICAfile\fR or
+/*	\fB-P \fICApath\fR, the OpenSSL library may augment the chain with
+/*	missing issuer certificates.  To see the actual chain sent by the
+/*	remote SMTP server leave \fICAfile\fR and \fICApath\fR unset.
+/* .IP "\fB-d \fImdalg\fR (default: \fBsha1\fR)"
+/*	The message digest algorithm to use for reporting remote SMTP server
+/*	fingerprints and matching against user provided certificate
+/*	fingerprints (with DANE TLSA records the algorithm is specified
+/*	in the DNS).
+/* .IP "\fB-f\fR"
+/*	Lookup the associated DANE TLSA RRset even when a hostname is not an
+/*	alias and its address records lie in an unsigned zone.  See
+/*	smtp_tls_force_insecure_host_tlsa_lookup for details.
+/* .IP "\fB-F \fICAfile.pem\fR (default: none)"
+/*	The PEM formatted CAfile for remote SMTP server certificate
+/*	verification.  By default no CAfile is used and no public CAs
+/*	are trusted.
+/* .IP "\fB-g \fIgrade\fR (default: medium)"
+/*	The minimum TLS cipher grade used by posttls-finger.  See
+/*	smtp_tls_mandatory_ciphers for details.
+/* .IP "\fB-h \fIhost_lookup\fR (default: \fBdns\fR)"
+/*	The hostname lookup methods used for the connection.  See the
+/*	documentation of smtp_host_lookup for syntax and semantics.
+/* .IP "\fB-H \fIchainfiles\fR (default: \fInone\fR)\fR"
+/*	List of files with a sequence PEM-encoded TLS client certificate
+/*	chains.  The list can be built-up incrementally, by specifying
+/*	the option multiple times, or all at once via a comma or
+/*	whitespace separated list of filenames.  Each chain starts with
+/*	a private key, which is followed immediately by the
+/*	corresponding certificate, and optionally by additional issuer
+/*	certificates. Each new key begins a new chain for the
+/*	corresponding algorithm.  This option is mutually exclusive with
+/*	the below \fB-k\fR and \fB-K\fR options.
+/* .IP "\fB-k \fIcertfile\fR (default: \fIkeyfile\fR)\fR"
+/*	File with PEM-encoded TLS client certificate chain. This
+/*	defaults to \fIkeyfile\fR if one is specified.
+/* .IP "\fB-K \fIkeyfile\fR (default: \fIcertfile\fR)"
+/*	File with PEM-encoded TLS client private key.
+/*	This defaults to \fIcertfile\fR if one is specified.
+/* .IP "\fB-l \fIlevel\fR (default: \fBdane\fR or \fBsecure\fR)"
+/*	The security level for the connection, default \fBdane\fR or
+/*	\fBsecure\fR depending on whether DNSSEC is available.  For syntax
+/*	and semantics, see the documentation of smtp_tls_security_level.
+/*	When \fBdane\fR or \fBdane-only\fR is supported and selected, if no
+/*	TLSA records are found, or all the records found are unusable, the
+/*	\fIsecure\fR level will be used instead.  The \fBfingerprint\fR
+/*	security level allows you to test certificate or public-key
+/*	fingerprint matches before you deploy them in the policy table.
+/* .IP
+/*	Note, since \fBposttls-finger\fR does not actually deliver any email,
+/*	the \fBnone\fR, \fBmay\fR and \fBencrypt\fR security levels are not
+/*	very useful.  Since \fBmay\fR and \fBencrypt\fR don't require peer
+/*	certificates, they will often negotiate anonymous TLS ciphersuites,
+/*	so you won't learn much about the remote SMTP server's certificates
+/*	at these levels if it also supports anonymous TLS (though you may
+/*	learn that the server supports anonymous TLS).
+/* .IP "\fB-L \fIlogopts\fR (default: \fBroutine,certmatch\fR)"
+/*	Fine-grained TLS logging options. To tune the TLS features logged
+/*	during the TLS handshake, specify one or more of:
+/* .RS
+/* .IP "\fB0, none\fR"
+/*	These yield no TLS logging; you'll generally want more, but this
+/*	is handy if you just want the trust chain:
+/* .RS
+/* .ad
+/* .nf
+/*	$ posttls-finger -cC -L none destination
+/* .fi
+/* .RE
+/* .IP "\fB1, routine, summary\fR"
+/*	These synonymous values yield a normal one-line summary of the TLS
+/*	connection.
+/* .IP "\fB2, debug\fR"
+/*	These synonymous values combine routine, ssl-debug, cache and verbose.
+/* .IP "\fB3, ssl-expert\fR"
+/*	These synonymous values combine debug with ssl-handshake-packet-dump.
+/*	For experts only.
+/* .IP "\fB4, ssl-developer\fR"
+/*	These synonymous values combine ssl-expert with ssl-session-packet-dump.
+/*	For experts only, and in most cases, use wireshark instead.
+/* .IP "\fBssl-debug\fR"
+/*	Turn on OpenSSL logging of the progress of the SSL handshake.
+/* .IP "\fBssl-handshake-packet-dump\fR"
+/*	Log hexadecimal packet dumps of the SSL handshake; for experts only.
+/* .IP "\fBssl-session-packet-dump\fR"
+/*	Log hexadecimal packet dumps of the entire SSL session; only useful
+/*	to those who can debug SSL protocol problems from hex dumps.
+/* .IP "\fBuntrusted\fR"
+/*	Logs trust chain verification problems.  This is turned on
+/*	automatically at security levels that use peer names signed
+/*	by Certification Authorities to validate certificates.  So while
+/*	this setting is recognized, you should never need to set it
+/*	explicitly.
+/* .IP "\fBpeercert\fR"
+/*	This logs a one line summary of the remote SMTP server certificate
+/*	subject, issuer, and fingerprints.
+/* .IP "\fBcertmatch\fR"
+/*	This logs remote SMTP server certificate matching, showing the CN
+/*	and each subjectAltName and which name matched.  With DANE, logs
+/*	matching of TLSA record trust-anchor and end-entity certificates.
+/* .IP "\fBcache\fR"
+/*	This logs session cache operations, showing whether session caching
+/*	is effective with the remote SMTP server.  Automatically used when
+/*	reconnecting with the \fB-r\fR option; rarely needs to be set
+/*	explicitly.
+/* .IP "\fBverbose\fR"
+/*	Enables verbose logging in the Postfix TLS driver; includes all of
+/*	peercert..cache and more.
+/* .RE
+/* .IP
+/*	The default is \fBroutine,certmatch\fR. After a reconnect,
+/*	\fBpeercert\fR, \fBcertmatch\fR and \fBverbose\fR are automatically
+/*	disabled while \fBcache\fR and \fBsummary\fR are enabled.
+/* .IP "\fB-m \fIcount\fR (default: \fB5\fR)"
+/*	When the \fB-r \fIdelay\fR option is specified, the \fB-m\fR option
+/*	determines the maximum number of reconnect attempts to use with
+/*	a server behind a load balancer, to see whether connection caching
+/*	is likely to be effective for this destination.  Some MTAs
+/*	don't expose the underlying server identity in their EHLO
+/*	response; with these servers there will never be more than
+/*	1 reconnection attempt.
+/* .IP "\fB-M \fIinsecure_mx_policy\fR (default: \fBdane\fR)"
+/*	The TLS policy for MX hosts with "secure" TLSA records when the
+/*	nexthop destination security level is \fBdane\fR, but the MX
+/*	record was found via an "insecure" MX lookup.  See the main.cf
+/*	documentation for smtp_tls_insecure_mx_policy for details.
+/* .IP "\fB-o \fIname=value\fR"
+/*	Specify zero or more times to override the value of the main.cf
+/*	parameter \fIname\fR with \fIvalue\fR.  Possible use-cases include
+/*	overriding the values of TLS library parameters, or "myhostname" to
+/*	configure the SMTP EHLO name sent to the remote server.
+/* .IP "\fB-p \fIprotocols\fR (default: !SSLv2)"
+/*	List of TLS protocols that posttls-finger will exclude or include.  See
+/*	smtp_tls_mandatory_protocols for details.
+/* .IP "\fB-P \fICApath/\fR (default: none)"
+/*	The OpenSSL CApath/ directory (indexed via c_rehash(1)) for remote
+/*	SMTP server certificate verification.  By default no CApath is used
+/*	and no public CAs are trusted.
+/* .IP "\fB-r \fIdelay\fR"
+/*	With a cacheable TLS session, disconnect and reconnect after \fIdelay\fR
+/*	seconds. Report whether the session is re-used. Retry if a new server
+/*	is encountered, up to 5 times or as specified with the \fB-m\fR option.
+/*	By default reconnection is disabled, specify a positive delay to
+/*	enable this behavior.
+/* .IP "\fB-s \fIservername\fR"
+/*	The server name to send with the TLS Server Name Indication (SNI)
+/*	extension.  When the server has DANE TLSA records, this parameter
+/*	is ignored and the TLSA base domain is used instead.  Otherwise, SNI is
+/*	not used by default, but can be enabled by specifying the desired value
+/*	with this option.
+/* .IP "\fB-S\fR"
+/*	Disable SMTP; that is, connect to an LMTP server. The default port for
+/*	LMTP over TCP is 24.  Alternative ports can specified by appending
+/*	"\fI:servicename\fR" or ":\fIportnumber\fR" to the destination
+/*	argument.
+/* .IP "\fB-t \fItimeout\fR (default: \fB30\fR)"
+/*	The TCP connection timeout to use.  This is also the timeout for
+/*	reading the remote server's 220 banner.
+/* .IP "\fB-T \fItimeout\fR (default: \fB30\fR)"
+/*	The SMTP/LMTP command timeout for EHLO/LHLO, STARTTLS and QUIT.
+/* .IP "\fB-v\fR"
+/*	Enable verbose Postfix logging.  Specify more than once to increase
+/*	the level of verbose logging.
+/* .IP "\fB-w\fR"
+/*	Enable outgoing TLS wrapper mode, or SMTPS support.  This is typically
+/*	provided on port 465 by servers that are compatible with the ad-hoc
+/*	SMTP in SSL protocol, rather than the standard STARTTLS protocol.
+/*	The destination \fIdomain\fR:\fIport\fR should of course provide such
+/*	a service.
+/* .IP "\fB-X\fR"
+/*	Enable \fBtlsproxy\fR(8) mode. This is an unsupported mode,
+/*	for program development only.
+/* .IP "[\fBinet:\fR]\fIdomain\fR[:\fIport\fR]"
+/*	Connect via TCP to domain \fIdomain\fR, port \fIport\fR. The default
+/*	port is \fBsmtp\fR (or 24 with LMTP).  With SMTP an MX lookup is
+/*	performed to resolve the domain to a host, unless the domain is
+/*	enclosed in \fB[]\fR.  If you want to connect to a specific MX host,
+/*	for instance \fImx1.example.com\fR, specify [\fImx1.example.com\fR]
+/*	as the destination and \fIexample.com\fR as a \fBmatch\fR argument.
+/*	When using DNS, the destination domain is assumed fully qualified
+/*	and no default domain or search suffixes are applied; you must use
+/*	fully-qualified names or also enable \fBnative\fR host lookups
+/*	(these don't support \fBdane\fR or \fBdane-only\fR as no DNSSEC
+/*	validation information is available via \fBnative\fR lookups).
+/* .IP "\fBunix:\fIpathname\fR"
+/*	Connect to the UNIX-domain socket at \fIpathname\fR. LMTP only.
+/* .IP "\fBmatch ...\fR"
+/*	With no match arguments specified, certificate peername matching uses
+/*	the compiled-in default strategies for each security level.  If you
+/*	specify one or more arguments, these will be used as the list of
+/*	certificate or public-key digests to match for the \fBfingerprint\fR
+/*	level, or as the list of DNS names to match in the certificate at the
+/*	\fBverify\fR and \fBsecure\fR levels.  If the security level is
+/*	\fBdane\fR, or \fBdane-only\fR the match names are ignored, and
+/*	\fBhostname, nexthop\fR strategies are used.
+/* .ad
+/* .fi
+/* ENVIRONMENT
+/* .ad
+/* .fi
+/* .IP \fBMAIL_CONFIG\fR
+/*	Read configuration parameters from a non-default location.
+/* .IP \fBMAIL_VERBOSE\fR
+/*	Same as \fB-v\fR option.
+/* SEE ALSO
+/*	smtp-source(1), SMTP/LMTP message source
+/*	smtp-sink(1), SMTP/LMTP message dump
+/*
+/* README FILES
+/* .ad
+/* .fi
+/*	Use "\fBpostconf readme_directory\fR" or "\fBpostconf
+/*	html_directory\fR" to locate this information.
+/* .na
+/* .nf
+/*	TLS_README, Postfix STARTTLS howto
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*
+/*	Wietse Venema
+/*	Google, Inc.
+/*	111 8th Avenue
+/*	New York, NY 10011, USA
+/*
+/*	Viktor Dukhovni
+/*--*/
+
+ /*
+  * System library.
+  */
+#include <sys_defs.h>
+#include <stdarg.h>
+#include <string.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#ifdef STRCASECMP_IN_STRINGS_H
+#include <strings.h>
+#endif
+
+ /*
+  * Utility library.
+  */
+#include <msg.h>
+#include <msg_vstream.h>
+#include <vstring.h>
+#include <vstream.h>
+#include <vstring_vstream.h>
+#include <mymalloc.h>
+#include <stringops.h>
+#include <argv.h>
+#include <name_mask.h>
+#include <name_code.h>
+#include <chroot_uid.h>
+#include <host_port.h>
+#include <inet_proto.h>
+#include <iostuff.h>
+#include <timed_connect.h>
+#include <sane_connect.h>
+#include <myaddrinfo.h>
+#include <sock_addr.h>
+#include <midna_domain.h>
+#include <clean_env.h>
+
+#define STR(x)		vstring_str(x)
+
+ /*
+  * Global library.
+  */
+#include <mail_params.h>
+#include <mail_conf.h>
+#include <smtp_stream.h>
+#include <dsn_buf.h>
+#include <mail_parm_split.h>
+#include <mail_proto.h>
+
+/* DNS library. */
+
+#include <dns.h>
+
+ /*
+  * master library
+  */
+#include <mail_server.h>
+
+ /*
+  * TLS Library
+  */
+#define TLS_INTERNAL
+#include <tls.h>
+
+#ifdef USE_TLS
+#include <tls_proxy.h>
+#include <openssl/engine.h>
+#endif
+
+ /*
+  * Application specific
+  */
+#include "tlsmgrmem.h"
+
+static int conn_tmout = 30;
+static int smtp_tmout = 30;
+
+#define HOST_FLAG_DNS		(1<<0)
+#define HOST_FLAG_NATIVE	(1<<1)
+
+#define MISC_FLAG_PREF_IPV6	(1<<0)
+#define MISC_FLAG_PREF_IPV4	(1<<1)
+
+static const NAME_MASK lookup_masks[] = {
+    "dns", HOST_FLAG_DNS,
+    "native", HOST_FLAG_NATIVE,
+    0,
+};
+
+static const NAME_CODE addr_pref_map[] = {
+    INET_PROTO_NAME_IPV6, MISC_FLAG_PREF_IPV6,
+    INET_PROTO_NAME_IPV4, MISC_FLAG_PREF_IPV4,
+    INET_PROTO_NAME_ANY, 0,
+    0, -1,
+};
+
+typedef struct OPTIONS {
+    char   *logopts;
+    char   *level;
+    ARGV   *tas;
+    char   *host_lookup;
+    char   *addr_pref;
+} OPTIONS;
+
+ /*
+  * Per-session data structure with state.
+  * 
+  * This software can maintain multiple parallel connections to the same SMTP
+  * server. However, it makes no more than one connection request at a time
+  * to avoid overwhelming the server with SYN packets and having to back off.
+  * Back-off would screw up the benchmark. Pending connection requests are
+  * kept in a linear list.
+  */
+typedef struct STATE {
+    int     smtp;			/* SMTP or LMTP? */
+    int     host_lookup;		/* dns|native|dns,native */
+    int     addr_pref;			/* v4, v6, both */
+    int     log_mask;			/* via tls_log_mask() */
+    int     reconnect;			/* -r option */
+    int     max_reconnect;		/* -m option */
+    int     force_tlsa;			/* -f option */
+    unsigned port;			/* TCP port */
+    char   *dest;			/* Full destination spec */
+    char   *paddr;			/* XXX printable addr for proxy */
+    char   *addrport;			/* [addr]:port */
+    char   *namaddrport;		/* name[addr]:port */
+    char   *nexthop;			/* Nexthop domain for verification */
+    char   *hostname;			/* Hostname for verification */
+    DNS_RR *addr;			/* IPv[46] Address to (re)connect to */
+    DNS_RR *mx;				/* MX RRset qname, rname, valid */
+    int     pass;			/* Pass number, 2 for reconnect */
+    int     nochat;			/* disable chat logging */
+    char   *helo;			/* Server name from EHLO reply */
+    DSN_BUF *why;			/* SMTP-style error message */
+    VSTRING *buffer;			/* Response buffer */
+    VSTREAM *stream;			/* Open connection */
+    int     level;			/* TLS security level */
+    int     wrapper_mode;		/* SMTPS support */
+#ifdef USE_TLS
+    char   *mdalg;			/* fingerprint digest algorithm */
+    char   *CAfile;			/* Trusted public CAs */
+    char   *CApath;			/* Trusted public CAs */
+    char   *chains;			/* TLS client certificate chain files */
+    char   *certfile;			/* TLS client certificate file */
+    char   *keyfile;			/* TLS client key file */
+    char   *sni;			/* Server SNI name */
+    ARGV   *match;			/* match arguments */
+    int     print_trust;		/* -C option */
+    BIO    *tls_bio;			/* BIO wrapper for stdout */
+    TLS_APPL_STATE *tls_ctx;		/* Application TLS context */
+    TLS_SESS_STATE *tls_context;	/* Session TLS context */
+    TLS_DANE *dane;			/* DANE TLSA validation structure */
+    TLS_DANE *ddane;			/* DANE TLSA from DNS */
+    char   *grade;			/* Minimum cipher grade */
+    char   *protocols;			/* Protocol inclusion/exclusion */
+    int     mxinsec_level;		/* DANE for insecure MX RRs? */
+    int     tlsproxy_mode;
+#endif
+    OPTIONS options;			/* JCL */
+} STATE;
+
+static DNS_RR *host_addr(STATE *, const char *);
+
+#define HNAME(addr) (addr->qname)
+
+ /*
+  * Structure with broken-up SMTP server response.
+  */
+typedef struct {			/* server response */
+    int     code;			/* status */
+    char   *str;			/* text */
+    VSTRING *buf;			/* origin of text */
+} RESPONSE;
+
+
+/* command - send an SMTP command */
+
+static void PRINTFLIKE(3, 4) command(STATE *state, int verbose, char *fmt,...)
+{
+    VSTREAM *stream = state->stream;
+    VSTRING *buf;
+    va_list ap;
+    char   *line;
+
+    buf = vstring_alloc(100);
+    va_start(ap, fmt);
+    vstring_vsprintf(buf, fmt, ap);
+    va_end(ap);
+    line = vstring_str(buf);
+
+    while (line && *line) {
+	char   *nextline = strchr(line, '\n');
+
+	if (nextline)
+	    *nextline++ = '\0';
+	if (verbose && !state->nochat)
+	    msg_info("> %s", line);
+	smtp_printf(stream, "%s", line);
+	line = nextline;
+    }
+
+    vstring_free(buf);
+}
+
+/* response - read and process SMTP server response */
+
+static RESPONSE *response(STATE *state, int verbose)
+{
+    VSTREAM *stream = state->stream;
+    VSTRING *buf = state->buffer;
+    static RESPONSE rdata;
+    int     more;
+    char   *cp;
+
+    /*
+     * Initialize the response data buffer. smtp_get() defends against a
+     * denial of service attack by limiting the amount of single-line text,
+     * and the loop below limits the amount of multi-line text that we are
+     * willing to store.
+     */
+    if (rdata.buf == 0)
+	rdata.buf = vstring_alloc(100);
+
+    /*
+     * Censor out non-printable characters in server responses. Concatenate
+     * multi-line server responses. Separate the status code from the text.
+     * Leave further parsing up to the application.
+     */
+#define BUF ((char *) vstring_str(buf))
+    VSTRING_RESET(rdata.buf);
+    for (;;) {
+	smtp_get(buf, stream, var_line_limit, SMTP_GET_FLAG_SKIP);
+	for (cp = BUF; *cp != 0; cp++)
+	    if (!ISPRINT(*cp) && !ISSPACE(*cp))
+		*cp = '?';
+	cp = BUF;
+	if (verbose && !state->nochat)
+	    msg_info("< %s", cp);
+	while (ISDIGIT(*cp))
+	    cp++;
+	rdata.code = (cp - BUF == 3 ? atoi(BUF) : 0);
+	if ((more = (*cp == '-')) != 0)
+	    cp++;
+	while (ISSPACE(*cp))
+	    cp++;
+	if (VSTRING_LEN(rdata.buf) < var_line_limit)
+	    vstring_strcat(rdata.buf, cp);
+	if (more == 0)
+	    break;
+	if (VSTRING_LEN(rdata.buf) < var_line_limit)
+	    VSTRING_ADDCH(rdata.buf, '\n');
+    }
+    VSTRING_TERMINATE(rdata.buf);
+    rdata.str = vstring_str(rdata.buf);
+    return (&rdata);
+}
+
+/* exception_text - translate exceptions from the smtp_stream module */
+
+static char *exception_text(int except)
+{
+    switch (except) {
+	case SMTP_ERR_EOF:
+	return ("lost connection");
+    case SMTP_ERR_TIME:
+	return ("timeout");
+    default:
+	msg_panic("exception_text: unknown exception %d", except);
+    }
+}
+
+/* greeting - read server's 220 greeting */
+
+static int greeting(STATE *state)
+{
+    VSTREAM *stream = state->stream;
+    int     except;
+    RESPONSE *resp;
+
+    /*
+     * Prepare for disaster.
+     */
+    smtp_stream_setup(stream, conn_tmout, 1);
+    if ((except = vstream_setjmp(stream)) != 0) {
+	msg_info("%s while reading server greeting", exception_text(except));
+	return (1);
+    }
+
+    /*
+     * Read and parse the server's SMTP greeting banner.
+     */
+    if (((resp = response(state, 1))->code / 100) != 2) {
+	msg_info("SMTP service not available: %d %s", resp->code, resp->str);
+	return (1);
+    }
+    return (0);
+}
+
+/* ehlo - send EHLO/LHLO */
+
+static RESPONSE *ehlo(STATE *state)
+{
+    int     except;
+    int     verbose;
+    volatile char *ehlo = state->smtp ? "EHLO" : "LHLO";
+    VSTREAM *stream = state->stream;
+    RESPONSE *resp;
+
+#ifdef USE_TLS
+    verbose = (state->pass == 1 && state->nochat == 0);
+#else
+    verbose = 1;
+#endif
+
+    /*
+     * Send the standard greeting with our hostname
+     */
+    if ((except = vstream_setjmp(stream)) != 0) {
+	msg_info("%s while sending %s", exception_text(except), ehlo);
+	return (0);
+    }
+    command(state, verbose, "%s %s", ehlo, var_myhostname);
+
+    resp = response(state, verbose);
+    if (resp->code / 100 != 2) {
+	msg_info("%s rejected: %d %s", ehlo, resp->code, resp->str);
+	return (0);
+    }
+    return resp;
+}
+
+#ifdef USE_TLS
+
+static void print_stack(STATE *state, x509_stack_t *sk, int trustout)
+{
+    int     i;
+
+    for (i = 0; i < sk_X509_num(sk); i++) {
+	X509   *cert = sk_X509_value(sk, i);
+	char    buf[CCERT_BUFSIZ];
+	X509_NAME *xn;
+	char   *digest;
+
+	if ((xn = X509_get_subject_name(cert)) != 0) {
+	    X509_NAME_oneline(xn, buf, sizeof buf);
+	    BIO_printf(state->tls_bio, "%2d subject: %s\n", i, buf);
+	}
+	if ((xn = X509_get_issuer_name(cert)) != 0) {
+	    X509_NAME_oneline(xn, buf, sizeof buf);
+	    BIO_printf(state->tls_bio, "    issuer: %s\n", buf);
+	}
+	digest = tls_cert_fprint(cert, state->mdalg);
+	BIO_printf(state->tls_bio, "   cert digest=%s\n", digest);
+	myfree(digest);
+
+	digest = tls_pkey_fprint(cert, state->mdalg);
+	BIO_printf(state->tls_bio, "   pkey digest=%s\n", digest);
+	myfree(digest);
+
+	if (trustout)
+	    PEM_write_bio_X509_AUX(state->tls_bio, cert);
+	else
+	    PEM_write_bio_X509(state->tls_bio, cert);
+    }
+}
+
+static void print_trust_info(STATE *state)
+{
+    x509_stack_t *sk = SSL_get_peer_cert_chain(state->tls_context->con);
+
+    if (sk != 0) {
+	BIO_printf(state->tls_bio, "\n---\nCertificate chain\n");
+	print_stack(state, sk, 0);
+    }
+#ifdef dane_verify_debug
+    /* print internally constructed untrusted chain */
+    if ((sk = state->tls_context->untrusted) != 0) {
+	BIO_printf(state->tls_bio, "\n---\nUntrusted chain\n");
+	print_stack(state, sk, 0);
+    }
+    /* print associated root CA */
+    if ((sk = state->tls_context->trusted) != 0) {
+	BIO_printf(state->tls_bio, "\n---\nTrusted chain\n");
+	print_stack(state, sk, 1);
+    }
+#endif
+}
+
+/* starttls - SMTP STARTTLS handshake */
+
+static int starttls(STATE *state)
+{
+    VSTRING *cipher_exclusions;
+    int     except;
+    RESPONSE *resp;
+    VSTREAM *stream = state->stream;
+    TLS_CLIENT_START_PROPS start_props;
+    TLS_CLIENT_INIT_PROPS init_props;
+    VSTREAM *tlsproxy;
+    VSTRING *port_buf;
+    int     cwd_fd;
+
+    if (state->wrapper_mode == 0) {
+	/* SMTP stream with deadline timeouts */
+	smtp_stream_setup(stream, smtp_tmout, 1);
+	if ((except = vstream_setjmp(stream)) != 0) {
+	    msg_fatal("%s while sending STARTTLS", exception_text(except));
+	    return (1);
+	}
+	command(state, state->pass == 1, "STARTTLS");
+
+	resp = response(state, state->pass == 1);
+	if (resp->code / 100 != 2) {
+	    msg_info("STARTTLS rejected: %d %s", resp->code, resp->str);
+	    return (1);
+	}
+
+	/*
+	 * Discard any plain-text data that may be piggybacked after the
+	 * server's 220 STARTTLS reply. Should we abort the session instead?
+	 */
+	vstream_fpurge(stream, VSTREAM_PURGE_READ);
+    }
+#define ADD_EXCLUDE(vstr, str) \
+    do { \
+	if (*(str)) \
+	    vstring_sprintf_append((vstr), "%s%s", \
+				   VSTRING_LEN(vstr) ? " " : "", (str)); \
+    } while (0)
+
+    cipher_exclusions = vstring_alloc(10);
+    ADD_EXCLUDE(cipher_exclusions, DEF_SMTP_TLS_EXCL_CIPH);
+    if (TLS_REQUIRED(state->level))
+	ADD_EXCLUDE(cipher_exclusions, DEF_SMTP_TLS_MAND_EXCL);
+
+    /*
+     * If we're authenticating suppress anonymous ciphersuites, otherwise at
+     * least encrypt, not much point in doing neither.
+     */
+    if (TLS_MUST_MATCH(state->level))
+	ADD_EXCLUDE(cipher_exclusions, "aNULL");
+    else
+	ADD_EXCLUDE(cipher_exclusions, "eNULL");
+
+    if (state->tlsproxy_mode) {
+	TLS_CLIENT_PARAMS tls_params;
+
+	/*
+	 * Send all our wishes in one big request.
+	 */
+	TLS_PROXY_CLIENT_INIT_PROPS(&init_props,
+				    log_param = "-L option",
+				    log_level = state->options.logopts,
+				    verifydepth = DEF_SMTP_TLS_SCERT_VD,
+				    cache_type = TLS_MGR_SCACHE_SMTP,
+				    chain_files = state->chains,
+				    cert_file = state->certfile,
+				    key_file = state->keyfile,
+				    dcert_file = "",
+				    dkey_file = "",
+				    eccert_file = "",
+				    eckey_file = "",
+				    CAfile = state->CAfile,
+				    CApath = state->CApath,
+				    mdalg = state->mdalg);
+	TLS_PROXY_CLIENT_START_PROPS(&start_props,
+				     timeout = smtp_tmout,
+				     tls_level = state->level,
+				     nexthop = state->nexthop,
+				     host = state->hostname,
+				     namaddr = state->namaddrport,
+				     sni = state->sni,
+				     serverid = state->addrport,
+				     helo = state->helo ? state->helo : "",
+				     protocols = state->protocols,
+				     cipher_grade = state->grade,
+				     cipher_exclusions
+				     = vstring_str(cipher_exclusions),
+				     matchargv = state->match,
+				     mdalg = state->mdalg,
+				     dane = state->ddane ?
+				     state->ddane : state->dane);
+
+#define PROXY_OPEN_FLAGS \
+        (TLS_PROXY_FLAG_ROLE_CLIENT | TLS_PROXY_FLAG_SEND_CONTEXT)
+#define var_tlsproxy_service
+
+	if ((cwd_fd = open(".", O_RDONLY)) < 0)
+	    msg_fatal("open(\".\", O_RDONLY): %m");
+	if (chdir(var_queue_dir) < 0)
+	    msg_fatal("chdir(%s): %m", var_queue_dir);
+	port_buf = vstring_alloc(100);
+	vstring_sprintf(port_buf, "%d", ntohs(state->port));
+	tlsproxy =
+	    tls_proxy_open(DEF_TLSPROXY_SERVICE /* TODO */ , PROXY_OPEN_FLAGS,
+			   state->stream, state->paddr, STR(port_buf),
+			   smtp_tmout, smtp_tmout, state->addrport,
+			   tls_proxy_client_param_from_config(&tls_params),
+			   &init_props, &start_props);
+	vstring_free(port_buf);
+	if (fchdir(cwd_fd) < 0)
+	    msg_fatal("fchdir: %m");
+	(void) close(cwd_fd);
+
+	/*
+	 * To insert tlsproxy(8) between this process and the remote SMTP
+	 * server, we swap the file descriptors between the tlsproxy and
+	 * session->stream VSTREAMS, so that we don't lose all the
+	 * user-configurable session->stream attributes (such as longjump
+	 * buffers or timeouts).
+	 * 
+	 * TODO: the tlsproxy RPCs should return more error detail than a "NO"
+	 * result.
+	 */
+	if (tlsproxy == 0) {
+	    state->tls_context = 0;
+	} else {
+	    vstream_control(tlsproxy,
+			    CA_VSTREAM_CTL_DOUBLE,
+			    CA_VSTREAM_CTL_END);
+	    vstream_control(state->stream,
+			    CA_VSTREAM_CTL_SWAP_FD(tlsproxy),
+			    CA_VSTREAM_CTL_END);
+	    (void) vstream_fclose(tlsproxy);	/* direct-to-server stream! */
+
+	    /*
+	     * There must not be any pending data in the stream buffers
+	     * before we read the TLS context attributes.
+	     */
+	    vstream_fpurge(state->stream, VSTREAM_PURGE_BOTH);
+
+	    /*
+	     * After plumbing the plaintext stream, receive the TLS context
+	     * object. For this we use the same VSTREAM buffer that we also
+	     * use to receive subsequent SMTP commands, therefore we must be
+	     * prepared for the possibility that the remote SMTP server
+	     * starts talking immediately. The tlsproxy implementation sends
+	     * the TLS context before remote content. The attribute protocol
+	     * is robust enough that an adversary cannot insert their own TLS
+	     * context attributes.
+	     */
+	    state->tls_context = tls_proxy_context_receive(state->stream);
+	    if (state->log_mask &
+		(TLS_LOG_CERTMATCH | TLS_LOG_VERBOSE | TLS_LOG_PEERCERT))
+		msg_info("%s: subject_CN=%s, issuer_CN=%s, "
+			 "fingerprint=%s, pkey_fingerprint=%s",
+			 state->namaddrport, state->tls_context->peer_CN,
+			 state->tls_context->issuer_CN,
+			 state->tls_context->peer_cert_fprint,
+			 state->tls_context->peer_pkey_fprint);
+	    tls_log_summary(TLS_ROLE_CLIENT, TLS_USAGE_NEW,
+			    state->tls_context);
+	}
+    } else {					/* tls_proxy_mode */
+	state->tls_context =
+	    TLS_CLIENT_START(&start_props,
+			     ctx = state->tls_ctx,
+			     stream = stream,
+			     fd = -1,
+			     timeout = smtp_tmout,
+			     tls_level = state->level,
+			     nexthop = state->nexthop,
+			     host = state->hostname,
+			     namaddr = state->namaddrport,
+			     sni = state->sni,
+			     serverid = state->addrport,
+			     helo = state->helo ? state->helo : "",
+			     protocols = state->protocols,
+			     cipher_grade = state->grade,
+			     cipher_exclusions
+			     = vstring_str(cipher_exclusions),
+			     matchargv = state->match,
+			     mdalg = state->mdalg,
+			  dane = state->ddane ? state->ddane : state->dane);
+    }						/* tlsproxy_mode */
+    vstring_free(cipher_exclusions);
+    if (state->helo) {
+	myfree(state->helo);
+	state->helo = 0;
+    }
+    if (state->tls_context == 0) {
+	/* We must avoid further I/O, the peer is in an undefined state. */
+	(void) vstream_fpurge(stream, VSTREAM_PURGE_BOTH);
+	(void) vstream_fclose(stream);
+	state->stream = 0;
+	return (1);
+    }
+    if (state->wrapper_mode && greeting(state) != 0)
+	return (1);
+
+    if (state->pass == 1) {
+	ehlo(state);
+	if (!TLS_CERT_IS_PRESENT(state->tls_context))
+	    msg_info("Server is anonymous");
+	else if (state->tlsproxy_mode == 0) {
+	    if (state->print_trust)
+		print_trust_info(state);
+	    state->log_mask &= ~(TLS_LOG_CERTMATCH | TLS_LOG_PEERCERT |
+				 TLS_LOG_VERBOSE | TLS_LOG_UNTRUSTED);
+	}
+	state->log_mask |= TLS_LOG_CACHE | TLS_LOG_SUMMARY;
+	tls_update_app_logmask(state->tls_ctx, state->log_mask);
+    }
+    return (0);
+}
+
+#endif
+
+/* doproto - do SMTP handshake */
+
+static int doproto(STATE *state)
+{
+    VSTREAM *stream = state->stream;
+    RESPONSE *resp;
+    int     except;
+    int     n;
+    char   *lines;
+    char   *words = 0;
+    char   *word;
+
+    if (!state->wrapper_mode) {
+	if (greeting(state) != 0)
+	    return (1);
+	if ((resp = ehlo(state)) == 0)
+	    return (1);
+
+	lines = resp->str;
+	for (n = 0; (words = mystrtok(&lines, "\n")) != 0; ++n) {
+	    if ((word = mystrtok(&words, " \t=")) != 0) {
+		if (n == 0)
+		    state->helo = mystrdup(word);
+		if (strcasecmp(word, "STARTTLS") == 0)
+		    break;
+	    }
+	}
+    }
+#ifdef USE_TLS
+    if ((state->wrapper_mode || words) && state->tls_ctx)
+	if (starttls(state))
+	    return (1);
+#endif
+
+    /*
+     * Prepare for disaster.
+     */
+    smtp_stream_setup(stream, smtp_tmout, 1);
+    if ((except = vstream_setjmp(stream)) != 0) {
+	msg_warn("%s while sending QUIT command", exception_text(except));
+	return (0);
+    }
+    command(state, 1, "QUIT");
+    (void) response(state, 1);
+    return (0);
+}
+
+/* connect_sock - connect a socket over some transport */
+
+static VSTREAM *connect_sock(int sock, struct sockaddr *sa, int salen,
+		           const char *name, const char *addr, STATE *state)
+{
+    DSN_BUF *why = state->why;
+    int     conn_stat;
+    int     saved_errno;
+    VSTREAM *stream;
+
+    if (conn_tmout > 0) {
+	non_blocking(sock, NON_BLOCKING);
+	conn_stat = timed_connect(sock, sa, salen, conn_tmout);
+	saved_errno = errno;
+	non_blocking(sock, BLOCKING);
+	errno = saved_errno;
+    } else {
+	conn_stat = sane_connect(sock, sa, salen);
+    }
+    if (conn_stat < 0) {
+	if (state->port)
+	    dsb_simple(why, "4.4.1", "connect to %s[%s]:%d: %m",
+		       name, addr, ntohs(state->port));
+	else
+	    dsb_simple(why, "4.4.1", "connect to %s[%s]: %m", name, addr);
+	close(sock);
+	return (0);
+    }
+    stream = vstream_fdopen(sock, O_RDWR);
+    state->namaddrport =
+	vstring_export(state->port == 0 ?
+		  vstring_sprintf(vstring_alloc(10), "%s[%s]", name, addr) :
+		       vstring_sprintf(vstring_alloc(10), "%s[%s]:%u",
+				       name, addr, ntohs(state->port)));
+    state->addrport =
+	vstring_export(state->port == 0 ?
+		       vstring_sprintf(vstring_alloc(10), "%s", addr) :
+		       vstring_sprintf(vstring_alloc(10), "[%s]:%u",
+				       addr, ntohs(state->port)));
+
+    state->paddr = mystrdup(addr);		/* XXX for tlsproxy */
+
+    /*
+     * Avoid poor performance when TCP MSS > VSTREAM_BUFSIZE.
+     */
+    if (sa->sa_family == AF_INET
+#ifdef AF_INET6
+	|| sa->sa_family == AF_INET6
+#endif
+	)
+	vstream_tweak_tcp(stream);
+
+    return (stream);
+}
+
+/* connect_unix - connect to a unix-domain socket */
+
+static VSTREAM *connect_unix(STATE *state, const char *path)
+{
+    static const char *myname = "connect_unix";
+    DSN_BUF *why = state->why;
+    struct sockaddr_un sock_un;
+    int     len = strlen(path);
+    int     sock;
+
+    if (!state->nexthop)
+	state->nexthop = mystrdup(var_myhostname);
+    state->hostname = mystrdup(var_myhostname);
+
+    dsb_reset(why);				/* Paranoia */
+
+    /*
+     * Sanity checks.
+     */
+    if (len >= (int) sizeof(sock_un.sun_path)) {
+	dsb_simple(why, "4.3.5", "unix-domain name too long: %s", path);
+	return (0);
+    }
+
+    /*
+     * Initialize.
+     */
+    memset((void *) &sock_un, 0, sizeof(sock_un));
+    sock_un.sun_family = AF_UNIX;
+#ifdef HAS_SUN_LEN
+    sock_un.sun_len = len + 1;
+#endif
+    memcpy(sock_un.sun_path, path, len + 1);
+
+    /*
+     * Create a client socket.
+     */
+    if ((sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
+	msg_fatal("%s: socket: %m", myname);
+
+    /*
+     * Connect to the server.
+     */
+    if (msg_verbose)
+	msg_info("%s: trying: %s...", myname, path);
+
+    return (connect_sock(sock, (struct sockaddr *) &sock_un, sizeof(sock_un),
+			 var_myhostname, path, state));
+}
+
+/* connect_addr - connect to explicit address */
+
+static VSTREAM *connect_addr(STATE *state, DNS_RR *addr)
+{
+    static const char *myname = "connect_addr";
+    DSN_BUF *why = state->why;
+    struct sockaddr_storage ss;		/* remote */
+    struct sockaddr *sa = (struct sockaddr *) &ss;
+    SOCKADDR_SIZE salen = sizeof(ss);
+    MAI_HOSTADDR_STR hostaddr;
+    int     sock;
+
+    dsb_reset(why);				/* Paranoia */
+
+    /*
+     * Sanity checks.
+     */
+    if (dns_rr_to_sa(addr, state->port, sa, &salen) != 0) {
+	msg_warn("%s: skip address type %s: %m",
+		 myname, dns_strtype(addr->type));
+	dsb_simple(why, "4.4.0", "network address conversion failed: %m");
+	return (0);
+    }
+
+    /*
+     * Initialize.
+     */
+    if ((sock = socket(sa->sa_family, SOCK_STREAM, 0)) < 0)
+	msg_fatal("%s: socket: %m", myname);
+
+    if (inet_windowsize > 0)
+	set_inet_windowsize(sock, inet_windowsize);
+
+    /*
+     * Connect to the server.
+     */
+    SOCKADDR_TO_HOSTADDR(sa, salen, &hostaddr, (MAI_SERVPORT_STR *) 0, 0);
+    if (msg_verbose)
+	msg_info("%s: trying: %s[%s] port %d...",
+		 myname, HNAME(addr), hostaddr.buf, ntohs(state->port));
+
+    return (connect_sock(sock, sa, salen, HNAME(addr), hostaddr.buf, state));
+}
+
+#define HAS_DSN(why)		(STR((why)->status)[0] != 0)
+#define HAS_SOFT_DSN(why)	(STR((why)->status)[0] == '4')
+#define HAS_HARD_DSN(why)	(STR((why)->status)[0] == '5')
+#define HAS_LOOP_DSN(why) \
+    (HAS_DSN(why) && strcmp(STR((why)->status) + 1, ".4.6") == 0)
+
+#define SET_SOFT_DSN(why)	(STR((why)->status)[0] = '4')
+#define SET_HARD_DSN(why)	(STR((why)->status)[0] = '5')
+
+/* addr_one - address lookup for one host name */
+
+static DNS_RR *addr_one(STATE *state, DNS_RR *addr_list, const char *host,
+			        int res_opt, unsigned pref)
+{
+    static const char *myname = "addr_one";
+    DSN_BUF *why = state->why;
+    DNS_RR *addr = 0;
+    DNS_RR *rr;
+    int     aierr;
+    struct addrinfo *res0;
+    struct addrinfo *res;
+    INET_PROTO_INFO *proto_info = inet_proto_info();
+    int     found;
+
+    if (msg_verbose)
+	msg_info("%s: host %s", myname, host);
+
+    /*
+     * Interpret a numerical name as an address.
+     */
+    if (hostaddr_to_sockaddr(host, (char *) 0, 0, &res0) == 0
+     && strchr((char *) proto_info->sa_family_list, res0->ai_family) != 0) {
+	if ((addr = dns_sa_to_rr(host, pref, res0->ai_addr)) == 0)
+	    msg_fatal("host %s: conversion error for address family %d: %m",
+		    host, ((struct sockaddr *) (res0->ai_addr))->sa_family);
+	addr_list = dns_rr_append(addr_list, addr);
+	freeaddrinfo(res0);
+	return (addr_list);
+    }
+
+    /*
+     * Use DNS lookup, but keep the option open to use native name service.
+     * 
+     * XXX A soft error dominates past and future hard errors. Therefore we
+     * should not clobber a soft error text and status code.
+     */
+    if (state->host_lookup & HOST_FLAG_DNS) {
+	switch (dns_lookup_v(host, res_opt, &addr, (VSTRING *) 0,
+			     why->reason, DNS_REQ_FLAG_NONE,
+			     proto_info->dns_atype_list)) {
+	case DNS_OK:
+	    for (rr = addr; rr; rr = rr->next)
+		rr->pref = pref;
+	    addr_list = dns_rr_append(addr_list, addr);
+	    return (addr_list);
+	default:
+	    dsb_status(why, "4.4.3");
+	    return (addr_list);
+	case DNS_FAIL:
+	    dsb_status(why, HAS_SOFT_DSN(why) ? "4.4.3" : "5.4.3");
+	    return (addr_list);
+	case DNS_INVAL:
+	    dsb_status(why, HAS_SOFT_DSN(why) ? "4.4.4" : "5.4.4");
+	    return (addr_list);
+	case DNS_NOTFOUND:
+	    dsb_status(why, HAS_SOFT_DSN(why) ? "4.4.4" : "5.4.4");
+	    /* maybe native naming service will succeed */
+	    break;
+	}
+    }
+
+    /*
+     * Use the native name service which also looks in /etc/hosts.
+     * 
+     * XXX A soft error dominates past and future hard errors. Therefore we
+     * should not clobber a soft error text and status code.
+     */
+#define RETRY_AI_ERROR(e) \
+        ((e) == EAI_AGAIN || (e) == EAI_MEMORY || (e) == EAI_SYSTEM)
+#ifdef EAI_NODATA
+#define DSN_NOHOST(e) \
+	((e) == EAI_AGAIN || (e) == EAI_NODATA || (e) == EAI_NONAME)
+#else
+#define DSN_NOHOST(e) \
+	((e) == EAI_AGAIN || (e) == EAI_NONAME)
+#endif
+
+    if (state->host_lookup & HOST_FLAG_NATIVE) {
+	if ((aierr = hostname_to_sockaddr(host, (char *) 0, 0, &res0)) != 0) {
+	    dsb_simple(why, (HAS_SOFT_DSN(why) || RETRY_AI_ERROR(aierr)) ?
+		       (DSN_NOHOST(aierr) ? "4.4.4" : "4.3.0") :
+		       (DSN_NOHOST(aierr) ? "5.4.4" : "5.3.0"),
+		       "unable to look up host %s: %s",
+		       host, MAI_STRERROR(aierr));
+	} else {
+	    for (found = 0, res = res0; res != 0; res = res->ai_next) {
+		if (strchr((char *) proto_info->sa_family_list, res->ai_family) == 0) {
+		    msg_info("skipping address family %d for host %s",
+			     res->ai_family, host);
+		    continue;
+		}
+		found++;
+		if ((addr = dns_sa_to_rr(host, pref, res->ai_addr)) == 0)
+		    msg_fatal("host %s: conversion error for address family %d: %m",
+		    host, ((struct sockaddr *) (res0->ai_addr))->sa_family);
+		addr_list = dns_rr_append(addr_list, addr);
+	    }
+	    freeaddrinfo(res0);
+	    if (found == 0) {
+		dsb_simple(why, HAS_SOFT_DSN(why) ? "4.4.4" : "5.4.4",
+			   "%s: host not found", host);
+	    }
+	    return (addr_list);
+	}
+    }
+
+    /*
+     * No further alternatives for host lookup.
+     */
+    return (addr_list);
+}
+
+/* mx_addr_list - address lookup for a list of mail exchangers */
+
+static DNS_RR *mx_addr_list(STATE *state, DNS_RR *mx_names)
+{
+    static const char *myname = "mx_addr_list";
+    DNS_RR *addr_list = 0;
+    DNS_RR *rr;
+    int     res_opt = 0;
+
+    if (mx_names->dnssec_valid)
+	res_opt = RES_USE_DNSSEC;
+#ifdef USE_TLS
+    else if (state->mxinsec_level > TLS_LEV_MAY)
+	res_opt = RES_USE_DNSSEC;
+#endif
+
+    for (rr = mx_names; rr; rr = rr->next) {
+	if (rr->type != T_MX)
+	    msg_panic("%s: bad resource type: %d", myname, rr->type);
+	addr_list = addr_one(state, addr_list, (char *) rr->data, res_opt,
+			     rr->pref);
+    }
+    return (addr_list);
+}
+
+/* smtp_domain_addr - mail exchanger address lookup */
+
+static DNS_RR *domain_addr(STATE *state, char *domain)
+{
+    DNS_RR *mx_names;
+    DNS_RR *addr_list = 0;
+    int     r = 0;			/* Resolver flags */
+    const char *aname;
+
+    dsb_reset(state->why);
+
+#if (RES_USE_DNSSEC != 0) && (RES_USE_EDNS0 != 0)
+    r |= RES_USE_DNSSEC;
+#endif
+
+    /*
+     * IDNA support.
+     */
+#ifndef NO_EAI
+    if (!allascii(domain) && (aname = midna_domain_to_ascii(domain)) != 0) {
+	msg_info("%s asciified to %s", domain, aname);
+    } else
+#endif
+	aname = domain;
+
+    switch (dns_lookup(aname, T_MX, r, &mx_names, (VSTRING *) 0,
+		       state->why->reason)) {
+    default:
+	dsb_status(state->why, "4.4.3");
+	break;
+    case DNS_INVAL:
+	dsb_status(state->why, "5.4.4");
+	break;
+    case DNS_NULLMX:
+	dsb_status(state->why, "5.1.0");
+	break;
+    case DNS_FAIL:
+	dsb_status(state->why, "5.4.3");
+	break;
+    case DNS_OK:
+	mx_names = dns_rr_sort(mx_names, dns_rr_compare_pref_any);
+	addr_list = mx_addr_list(state, mx_names);
+	state->mx = dns_rr_copy(mx_names);
+	dns_rr_free(mx_names);
+	if (addr_list == 0) {
+	    msg_warn("no MX host for %s has a valid address record", domain);
+	    break;
+	}
+#define COMPARE_ADDR(flags) \
+	((flags & MISC_FLAG_PREF_IPV6) ? dns_rr_compare_pref_ipv6 : \
+	 (flags & MISC_FLAG_PREF_IPV4) ? dns_rr_compare_pref_ipv4 : \
+	 dns_rr_compare_pref_any)
+	if (addr_list && addr_list->next) {
+	    addr_list = dns_rr_shuffle(addr_list);
+	    addr_list = dns_rr_sort(addr_list, COMPARE_ADDR(state->addr_pref));
+	}
+	break;
+    case DNS_NOTFOUND:
+	addr_list = host_addr(state, domain);
+	break;
+    }
+
+    return (addr_list);
+}
+
+/* host_addr - direct host lookup */
+
+static DNS_RR *host_addr(STATE *state, const char *host)
+{
+    DSN_BUF *why = state->why;
+    DNS_RR *addr_list;
+    int     res_opt = 0;
+    const char *ahost;
+
+    dsb_reset(why);				/* Paranoia */
+
+#if (RES_USE_DNSSEC != 0) && (RES_USE_EDNS0 != 0)
+    res_opt |= RES_USE_DNSSEC;
+#endif
+
+    /*
+     * IDNA support.
+     */
+#ifndef NO_EAI
+    if (!allascii(host) && (ahost = midna_domain_to_ascii(host)) != 0) {
+	msg_info("%s asciified to %s", host, ahost);
+    } else
+#endif
+	ahost = host;
+
+#define PREF0	0
+    addr_list = addr_one(state, (DNS_RR *) 0, ahost, res_opt, PREF0);
+    if (addr_list && addr_list->next) {
+	addr_list = dns_rr_shuffle(addr_list);
+	if (inet_proto_info()->ai_family_list[1] != 0)
+	    addr_list = dns_rr_sort(addr_list, COMPARE_ADDR(state->addr_pref));
+    }
+    return (addr_list);
+}
+
+/* dane_host_level - canidate host "dane" or degraded security level */
+
+static int dane_host_level(STATE *state, DNS_RR *addr)
+{
+    int     level = state->level;
+
+#ifdef USE_TLS
+    if (TLS_DANE_BASED(level)) {
+	if (state->mx == 0 || state->mx->dnssec_valid ||
+	    state->mxinsec_level > TLS_LEV_MAY) {
+	    if (state->log_mask & (TLS_LOG_CERTMATCH | TLS_LOG_VERBOSE))
+		tls_dane_verbose(1);
+	    else
+		tls_dane_verbose(0);
+
+	    /* See addr loop in connect_remote() */
+	    if (state->ddane)
+		tls_dane_free(state->ddane);
+
+	    /*
+	     * When TLSA lookups fail, next host.  If unusable or not found,
+	     * fallback to "secure"
+	     */
+	    state->ddane = tls_dane_resolve(state->port, "tcp", addr,
+					    state->force_tlsa);
+	    if (!state->ddane) {
+		dsb_simple(state->why, "4.7.5",
+			   "TLSA lookup error for %s:%u",
+			   HNAME(addr), ntohs(state->port));
+		level = TLS_LEV_INVALID;
+	    } else if (tls_dane_notfound(state->ddane)
+		       || tls_dane_unusable(state->ddane)) {
+		if (msg_verbose || level == TLS_LEV_DANE_ONLY)
+		    msg_info("no %sTLSA records found, "
+			     "resorting to \"secure\"",
+			     tls_dane_unusable(state->ddane) ?
+			     "usable " : "");
+		level = TLS_LEV_SECURE;
+	    } else if (!TLS_DANE_HASTA(state->ddane)
+		       && !TLS_DANE_HASEE(state->ddane)) {
+		msg_panic("DANE activated with no TLSA records to match");
+	    } else if (state->mx && !state->mx->dnssec_valid &&
+		       state->mxinsec_level == TLS_LEV_ENCRYPT) {
+		msg_info("TLSA RRs found, MX RRset insecure: just encrypt");
+		tls_dane_free(state->ddane);
+		state->ddane = 0;
+		level = TLS_LEV_ENCRYPT;
+	    } else {
+		if (state->match)
+		    argv_free(state->match);
+		argv_add(state->match = argv_alloc(2),
+			 state->ddane->base_domain, ARGV_END);
+		if (state->mx) {
+		    if (!state->mx->dnssec_valid) {
+			msg_info("MX RRset insecure: log verified as trusted");
+			level = TLS_LEV_HALF_DANE;
+		    }
+		    if (strcmp(state->mx->qname, state->mx->rname) == 0)
+			argv_add(state->match, state->mx->qname, ARGV_END);
+		    else
+			argv_add(state->match, state->mx->rname,
+				 state->mx->qname, ARGV_END);
+		}
+	    }
+	} else if (state->mx && !state->mx->dnssec_valid &&
+		   state->mxinsec_level == TLS_LEV_MAY) {
+	    msg_info("MX RRset is insecure: try to encrypt");
+	    level = TLS_LEV_MAY;
+	} else {
+	    level = TLS_LEV_SECURE;
+	}
+    }
+#endif
+
+    return (level);
+}
+
+/* parse_destination - parse host/port destination */
+
+static char *parse_destination(char *destination, char *def_service,
+			               char **hostp, unsigned *portp)
+{
+    char   *buf = mystrdup(destination);
+    char   *service;
+    struct servent *sp;
+    char   *protocol = "tcp";
+    unsigned port;
+    const char *err;
+
+    if (msg_verbose)
+	msg_info("parse_destination: %s %s", destination, def_service);
+
+    /*
+     * Parse the host/port information. We're working with a copy of the
+     * destination argument so the parsing can be destructive.
+     */
+    if ((err = host_port(buf, hostp, (char *) 0, &service, def_service)) != 0)
+	msg_fatal("%s in server description: %s", err, destination);
+
+    /*
+     * Convert service to port number, network byte order.
+     */
+    if (alldig(service)) {
+	if ((port = atoi(service)) >= 65536 || port == 0)
+	    msg_fatal("bad network port in destination: %s", destination);
+	*portp = htons(port);
+    } else {
+	if ((sp = getservbyname(service, protocol)) != 0)
+	    *portp = sp->s_port;
+	else if (strcmp(service, "smtp") == 0)
+	    *portp = htons(25);
+	else
+	    msg_fatal("unknown service: %s/%s", service, protocol);
+    }
+    return (buf);
+}
+
+/* connect_remote - connect to TCP destination or log an error */
+
+static void connect_remote(STATE *state, char *dest)
+{
+    DNS_RR *addr;
+    char   *buf;
+    char   *domain;
+
+    /* When reconnecting use IP address of previous session */
+    if (state->addr == 0) {
+	buf = parse_destination(dest, state->smtp ? "smtp" : "24",
+				&domain, &state->port);
+	if (!state->nexthop)
+	    state->nexthop = mystrdup(domain);
+	if (state->smtp == 0 || *dest == '[')
+	    state->addr = host_addr(state, domain);
+	else
+	    state->addr = domain_addr(state, domain);
+	myfree(buf);
+
+	if (state->addr == 0) {
+	    msg_info("Destination address lookup failed: %s",
+		     vstring_str(state->why->reason));
+	    return;
+	}
+    }
+    for (addr = state->addr; addr; addr = addr->next) {
+	int     level = dane_host_level(state, addr);
+
+	if (level == TLS_LEV_INVALID
+	    || (state->stream = connect_addr(state, addr)) == 0) {
+	    msg_info("Failed to establish session to %s via %s: %s",
+		     dest, HNAME(addr), vstring_str(state->why->reason));
+	    continue;
+	}
+	/* We have a connection */
+	state->level = level;
+	state->hostname = mystrdup(HNAME(addr));
+
+	/* We use the same address when reconnecting, so flush the rest. */
+	addr = dns_rr_copy(addr);
+	dns_rr_free(state->addr);
+	state->addr = addr;
+	break;
+    }
+}
+
+/* connect_dest - connect to given inet: or unix: destination */
+
+static int connect_dest(STATE *state)
+{
+    char   *dest = state->dest;
+
+    /*
+     * With LMTP we have direct-to-host delivery only. The destination may
+     * have multiple IP addresses.
+     */
+    if (state->smtp == 0) {
+	if (strncmp(dest, "unix:", 5) == 0) {
+	    state->stream = connect_unix(state, dest + 5);
+	    if (!state->stream)
+		msg_info("Failed to establish session to %s: %s",
+			 dest, vstring_str(state->why->reason));
+	    return (1);
+	}
+	if (strncmp(dest, "inet:", 5) == 0)
+	    dest += 5;
+    }
+    connect_remote(state, dest);
+
+    return (state->stream == 0);
+}
+
+static void disconnect_dest(STATE *state)
+{
+#ifdef USE_TLS
+    if (state->tls_context) {
+	if (state->tlsproxy_mode) {
+	    tls_proxy_context_free(state->tls_context);
+	} else {
+	    tls_client_stop(state->tls_ctx, state->stream,
+			    smtp_tmout, 0, state->tls_context);
+	}
+    }
+    state->tls_context = 0;
+    if (state->ddane)
+	tls_dane_free(state->ddane);
+    state->ddane = 0;
+#endif
+
+    if (state->stream)
+	vstream_fclose(state->stream);
+    state->stream = 0;
+
+    if (state->namaddrport)
+	myfree(state->namaddrport);
+    state->namaddrport = 0;
+
+    if (state->addrport)
+	myfree(state->addrport);
+    state->addrport = 0;
+
+    if (state->paddr)
+	myfree(state->paddr);
+    state->paddr = 0;
+
+    /* Reused on reconnect */
+    if (state->reconnect <= 0) {
+	if (state->addr)
+	    dns_rr_free(state->addr);
+	state->addr = 0;
+	if (state->mx)
+	    dns_rr_free(state->mx);
+	state->mx = 0;
+
+	if (state->nexthop)
+	    myfree(state->nexthop);
+	state->nexthop = 0;
+    }
+    if (state->hostname)
+	myfree(state->hostname);
+    state->hostname = 0;
+
+    dsb_free(state->why);
+    vstring_free(state->buffer);
+}
+
+static int finger(STATE *state)
+{
+    int     err;
+
+    /*
+     * smtp_get() makes sure the SMTP server cannot run us out of memory by
+     * sending never-ending lines of text.
+     */
+    state->buffer = vstring_alloc(100);
+    state->why = dsb_create();
+
+    if (!(err = connect_dest(state))) {
+	if (state->pass == 1 && !state->nochat)
+	    msg_info("Connected to %s", state->namaddrport);
+	err = doproto(state);
+    }
+    disconnect_dest(state);
+
+    if (err != 0)
+	return (1);
+
+#ifdef USE_TLS
+    if (state->tlsproxy_mode == 0 && state->reconnect > 0) {
+	int     cache_enabled;
+	int     cache_count;
+	int     cache_hits;
+
+	tlsmgrmem_status(&cache_enabled, &cache_count, &cache_hits);
+	if (cache_enabled && cache_count == 0) {
+	    msg_info("Server declined session caching. Done reconnecting.");
+	    state->reconnect = 0;
+	} else if (cache_hits > 0 && (state->log_mask & TLS_LOG_CACHE) != 0) {
+	    msg_info("Found a previously used server.  Done reconnecting.");
+	    state->reconnect = 0;
+	} else if (state->max_reconnect-- <= 0) {
+	    msg_info("Maximum reconnect count reached.");
+	    state->reconnect = 0;
+	}
+    }
+#endif
+
+    return (0);
+}
+
+#if defined(USE_TLS) && OPENSSL_VERSION_NUMBER < 0x10100000L
+
+/* ssl_cleanup - free memory allocated in the OpenSSL library */
+
+static void ssl_cleanup(void)
+{
+    ERR_remove_thread_state(0);		/* Thread-id is now a pointer */
+    ENGINE_cleanup();
+    CONF_modules_unload(1);
+    ERR_free_strings();
+    EVP_cleanup();
+    CRYPTO_cleanup_all_ex_data();
+}
+
+#endif					/* USE_TLS && OPENSSL_VERSION_NUMBER
+					 * < 0x10100000L */
+
+/* run - do what we were asked to do. */
+
+static int run(STATE *state)
+{
+
+    while (1) {
+	if (finger(state) != 0)
+	    break;
+	if (state->reconnect <= 0)
+	    break;
+	msg_info("Reconnecting after %d seconds", state->reconnect);
+	++state->pass;
+	sleep(state->reconnect);
+    }
+
+    return (0);
+}
+
+/* cleanup - free memory allocated in main */
+
+static void cleanup(STATE *state)
+{
+#ifdef USE_TLS
+    if (state->tls_ctx != 0)
+	tls_free_app_context(state->tls_ctx);
+    if (state->tls_bio)
+	(void) BIO_free(state->tls_bio);
+    state->tls_bio = 0;
+
+    myfree(state->mdalg);
+    myfree(state->CApath);
+    myfree(state->CAfile);
+    myfree(state->certfile);
+    myfree(state->keyfile);
+    myfree(state->sni);
+    if (state->options.level)
+	myfree(state->options.level);
+    myfree(state->options.logopts);
+    if (state->match)
+	argv_free(state->match);
+    if (state->options.tas)
+	argv_free(state->options.tas);
+    if (state->dane)
+	tls_dane_free(state->dane);
+
+    /* Flush and free DANE TLSA cache */
+    tls_dane_flush();
+    /* Flush and free memory tlsmgr cache */
+    tlsmgrmem_flush();
+    myfree(state->grade);
+    myfree(state->protocols);
+#endif
+    myfree(state->options.host_lookup);
+    myfree(state->dest);
+
+    mail_conf_flush();
+}
+
+/* usage - explain */
+
+static void usage(void)
+{
+#ifdef USE_TLS
+    fprintf(stderr, "usage: %s %s \\\n\t%s \\\n\t%s \\\n\t%s \\\n\t%s"
+	    " destination [match ...]\n", var_procname,
+	    "[-acCfSvw] [-t conn_tmout] [-T cmd_tmout] [-L logopts]",
+	 "[-h host_lookup] [-l level] [-d mdalg] [-g grade] [-p protocols]",
+	    "[-A tafile] [-F CAfile.pem] [-P CApath/] [-s servername]",
+	    "[ [-H chainfiles] | [-k certfile [-K keyfile]] ]",
+	    "[-m count] [-r delay] [-o name=value]");
+#else
+    fprintf(stderr, "usage: %s [-acStTv] [-h host_lookup] [-o name=value] destination\n",
+	    var_procname);
+#endif
+    exit(1);
+}
+
+/* tls_init - initialize application TLS library context */
+
+static void tls_init(STATE *state)
+{
+#ifdef USE_TLS
+    TLS_CLIENT_INIT_PROPS props;
+
+    if (state->level <= TLS_LEV_NONE)
+	return;
+
+    /* Needed for tls_dane_avail() and other DANE-related processing. */
+    state->tls_ctx =
+	TLS_CLIENT_INIT(&props,
+			log_param = "-L option",
+			log_level = state->options.logopts,
+			verifydepth = DEF_SMTP_TLS_SCERT_VD,
+			cache_type = "memory",
+			chain_files = state->chains,
+			cert_file = state->certfile,
+			key_file = state->keyfile,
+			dcert_file = "",
+			dkey_file = "",
+			eccert_file = "",
+			eckey_file = "",
+			CAfile = state->CAfile,
+			CApath = state->CApath,
+			mdalg = state->mdalg);
+#endif
+}
+
+/* override - update main.cf parameter */
+
+static void override(const char *nameval)
+{
+    char   *param_name;
+    char   *param_value;
+    char   *save = mystrdup(nameval);
+
+    if (split_nameval(save, &param_name, &param_value) != 0)
+	usage();
+    mail_conf_update(param_name, param_value);
+    myfree(save);
+}
+
+/* parse_options - (argc, argv) -> state */
+
+static void parse_options(STATE *state, int argc, char *argv[])
+{
+    int     c;
+
+    state->smtp = 1;
+    state->pass = 1;
+    state->reconnect = -1;
+    state->max_reconnect = 5;
+    state->wrapper_mode = 0;
+#ifdef USE_TLS
+    state->protocols = mystrdup("!SSLv2");
+    state->grade = mystrdup("medium");
+#endif
+    memset((void *) &state->options, 0, sizeof(state->options));
+    state->options.host_lookup = mystrdup("dns");
+
+#define OPTS "a:ch:o:St:T:v"
+#ifdef USE_TLS
+#define TLSOPTS "A:Cd:fF:g:H:k:K:l:L:m:M:p:P:r:s:wX"
+
+    state->mdalg = mystrdup("sha1");
+    state->CApath = mystrdup("");
+    state->CAfile = mystrdup("");
+    state->chains = mystrdup("");
+    state->certfile = mystrdup("");
+    state->keyfile = mystrdup("");
+    state->sni = mystrdup("");
+    state->options.tas = argv_alloc(1);
+    state->options.logopts = 0;
+    state->level = TLS_LEV_DANE;
+    state->mxinsec_level = TLS_LEV_DANE;
+    state->tlsproxy_mode = 0;
+#else
+#define TLSOPTS ""
+    state->level = TLS_LEV_NONE;
+#endif
+
+    while ((c = GETOPT(argc, argv, OPTS TLSOPTS)) > 0) {
+	switch (c) {
+	default:
+	    usage();
+	    break;
+	case 'a':
+	    state->options.addr_pref = mystrdup(optarg);
+	    break;
+	case 'c':
+	    state->nochat = 1;
+	    break;
+	case 'h':
+	    myfree(state->options.host_lookup);
+	    state->options.host_lookup = mystrdup(optarg);
+	    break;
+	case 'o':
+	    override(optarg);
+	    break;
+	case 'S':
+	    state->smtp = 0;
+	    break;
+	case 't':
+	    conn_tmout = atoi(optarg);
+	    break;
+	case 'T':
+	    smtp_tmout = atoi(optarg);
+	    break;
+	case 'v':
+	    msg_verbose++;
+	    break;
+#ifdef USE_TLS
+	case 'A':
+	    argv_add(state->options.tas, optarg, ARGV_END);
+	    break;
+	case 'C':
+	    state->print_trust = 1;
+	    break;
+	case 'd':
+	    myfree(state->mdalg);
+	    state->mdalg = mystrdup(optarg);
+	    break;
+	case 'f':
+	    state->force_tlsa = 1;
+	    break;
+	case 'F':
+	    myfree(state->CAfile);
+	    state->CAfile = mystrdup(optarg);
+	    break;
+	case 'g':
+	    myfree(state->grade);
+	    state->grade = mystrdup(optarg);
+	    break;
+	case 'H':
+	    {
+		char   *tmp;
+
+		if (*state->chains)
+		    tmp = concatenate(state->chains, ", ", optarg, (char *) 0);
+		else
+		    tmp = mystrdup(optarg);
+		myfree(state->chains);
+		state->chains = tmp;
+	    }
+	    break;
+	case 'k':
+	    myfree(state->certfile);
+	    state->certfile = mystrdup(optarg);
+	    if (!*state->keyfile) {
+		myfree(state->keyfile);
+		state->keyfile = mystrdup(optarg);
+	    }
+	    break;
+	case 'K':
+	    myfree(state->keyfile);
+	    state->keyfile = mystrdup(optarg);
+	    if (!*state->certfile) {
+		myfree(state->certfile);
+		state->certfile = mystrdup(optarg);
+	    }
+	    break;
+	case 'l':
+	    if (state->options.level)
+		myfree(state->options.level);
+	    state->options.level = mystrdup(optarg);
+	    break;
+	case 'L':
+	    if (state->options.logopts)
+		myfree(state->options.logopts);
+	    state->options.logopts = mystrdup(optarg);
+	    break;
+	case 'm':
+	    state->max_reconnect = atoi(optarg);
+	    break;
+	case 'M':
+	    switch (state->mxinsec_level = tls_level_lookup(optarg)) {
+	    case TLS_LEV_MAY:
+	    case TLS_LEV_ENCRYPT:
+	    case TLS_LEV_DANE:
+		break;
+	    default:
+		msg_fatal("bad '-M' option value: %s", optarg);
+	    }
+	    break;
+	case 'p':
+	    myfree(state->protocols);
+	    state->protocols = mystrdup(optarg);
+	    break;
+	case 'P':
+	    myfree(state->CApath);
+	    state->CApath = mystrdup(optarg);
+	    break;
+	case 'r':
+	    state->reconnect = atoi(optarg);
+	    break;
+	case 's':
+	    myfree(state->sni);
+	    state->sni = mystrdup(optarg);
+	    break;
+	case 'w':
+	    state->wrapper_mode = 1;
+	    break;
+	case 'X':
+	    state->tlsproxy_mode = 1;
+	    break;
+#endif
+	}
+    }
+
+    /*
+     * Address family preference.
+     */
+    state->addr_pref =
+	name_code(addr_pref_map, NAME_CODE_FLAG_NONE, state->options.addr_pref ?
+		  state->options.addr_pref : "any");
+    if (state->addr_pref < 0)
+	msg_fatal("bad '-a' option value: %s", state->options.addr_pref);
+
+#ifdef USE_TLS
+    if (state->tlsproxy_mode && state->reconnect >= 0)
+	msg_fatal("The -X and -r options are mutually exclusive");
+#endif
+
+    /*
+     * Select hostname lookup mechanisms.
+     */
+    state->host_lookup =
+	name_mask("-h option", lookup_masks, state->options.host_lookup ?
+		  state->options.host_lookup : "dns");
+
+#ifdef USE_TLS
+
+    if (*state->chains && *state->certfile)
+	msg_fatal("When the '-H' option is used, neither the '-k',"
+		  " nor the '-K' options may be used");
+
+    if (state->reconnect < 0)
+	tlsmgrmem_disable();
+
+    if (state->options.logopts == 0)
+	state->options.logopts = mystrdup("routine,certmatch");
+    state->log_mask = tls_log_mask("-L option", state->options.logopts);
+
+    if (state->options.level) {
+	state->level = tls_level_lookup(state->options.level);
+
+	switch (state->level) {
+	case TLS_LEV_NONE:
+	    if (state->wrapper_mode)
+		msg_fatal("SSL wrapper mode requires that TLS not be disabled");
+	    return;
+	case TLS_LEV_INVALID:
+	    msg_fatal("Invalid TLS level \"%s\"", state->options.level);
+	}
+    }
+
+    /*
+     * We first call tls_init(), which ultimately calls SSL_library_init(),
+     * since otherwise we can't tell whether we have the message digests
+     * required for DANE support.
+     */
+    tls_init(state);
+    if (TLS_DANE_BASED(state->level) && !tls_dane_avail()) {
+	msg_warn("DANE TLS support is not available, resorting to \"secure\"");
+	state->level = TLS_LEV_SECURE;
+    }
+    state->tls_bio = 0;
+    if (state->print_trust)
+	state->tls_bio = BIO_new_fp(stdout, BIO_NOCLOSE);
+
+#endif
+}
+
+/* parse_match - process match arguments */
+
+static void parse_match(STATE *state, int argc, char *argv[])
+{
+#ifdef USE_TLS
+
+    switch (state->level) {
+	case TLS_LEV_SECURE:
+	state->match = argv_alloc(2);
+	while (*argv)
+	    argv_split_append(state->match, *argv++, "");
+	if (state->match->argc == 0)
+	    argv_add(state->match, "nexthop", "dot-nexthop", ARGV_END);
+	break;
+    case TLS_LEV_VERIFY:
+	state->match = argv_alloc(1);
+	while (*argv)
+	    argv_split_append(state->match, *argv++, "");
+	if (state->match->argc == 0)
+	    argv_add(state->match, "hostname", ARGV_END);
+	break;
+    case TLS_LEV_FPRINT:
+	state->dane = tls_dane_alloc();
+	while (*argv)
+	    tls_dane_add_ee_digests((TLS_DANE *) state->dane,
+				    state->mdalg, *argv++, "");
+	break;
+    case TLS_LEV_DANE:
+    case TLS_LEV_DANE_ONLY:
+	state->match = argv_alloc(2);
+	argv_add(state->match, "nexthop", "hostname", ARGV_END);
+	break;
+    }
+#endif
+}
+
+/* parse_tas - process '-A' trust anchor file option */
+
+static void parse_tas(STATE *state)
+{
+#ifdef USE_TLS
+    char  **file;
+
+    if (!state->options.tas->argc)
+	return;
+
+    switch (state->level) {
+    default:
+	return;
+    case TLS_LEV_SECURE:
+    case TLS_LEV_VERIFY:
+	state->dane = tls_dane_alloc();
+	for (file = state->options.tas->argv; *file; ++file) {
+	    if (!tls_dane_load_trustfile((TLS_DANE *) state->dane, *file))
+		break;
+	}
+	if (*file)
+	    msg_fatal("Failed to load trust anchor file: %s", *file);
+	break;
+    }
+#endif
+}
+
+
+int     main(int argc, char *argv[])
+{
+    static STATE state;
+    char   *loopenv = getenv("VALGRINDLOOP");
+    int     loop = loopenv ? atoi(loopenv) : 1;
+    ARGV   *import_env;
+
+    /* Don't die when a peer goes away unexpectedly. */
+    signal(SIGPIPE, SIG_IGN);
+
+    /* We're a diagnostic utility, so diagnostic messages go to stdout. */
+    var_procname = mystrdup(basename(argv[0]));
+    set_mail_conf_str(VAR_PROCNAME, var_procname);
+    msg_vstream_init(var_procname, VSTREAM_OUT);
+
+    /*
+     * Load main.cf, parse command-line options, then process main.cf
+     * settings plus any command-line "-o" overrides.
+     */
+    mail_conf_suck();
+    parse_options(&state, argc, argv);
+    mail_params_init();
+    parse_tas(&state);
+
+    /* Enforce consistent operation of different Postfix parts. */
+    import_env = mail_parm_split(VAR_IMPORT_ENVIRON, var_import_environ);
+    update_env(import_env->argv);
+    argv_free(import_env);
+
+    argc -= optind;
+    argv += optind;
+
+    /* The first non-option argument is the destination. */
+    if (!argc)
+	usage();
+
+    state.dest = mystrdup(argv[0]);
+    parse_match(&state, --argc, ++argv);
+
+    /* Don't talk to remote systems as root */
+    if (!geteuid())
+	chroot_uid(0, var_mail_owner);
+
+    while (loop-- > 0)
+	run(&state);
+
+    /* Be valgrind friendly and clean-up */
+    cleanup(&state);
+
+    /* OpenSSL 1.1.0 and later (de)initialization is implicit */
+#if defined(USE_TLS) && OPENSSL_VERSION_NUMBER < 0x10100000L
+    ssl_cleanup();
+#endif
+
+    return (0);
+}
diff --git a/src/posttls-finger/tlsmgrmem.c b/src/posttls-finger/tlsmgrmem.c
new file mode 100644
index 0000000..bfbc3a1
--- /dev/null
+++ b/src/posttls-finger/tlsmgrmem.c
@@ -0,0 +1,143 @@
+/*++
+/* NAME
+/*	tlsmgrmem 3
+/* SUMMARY
+/*	Memory-based TLS manager interface for tlsfinger(1).
+/* SYNOPSIS
+/*	#ifdef	USE_TLS
+/*	#include <tlsmgrmem.h>
+/*
+/*	void	tlsmgrmem_disable()
+/*
+/*	void	tlsmgrmem_status(enable, count, hits)
+/*	int	*enable;
+/*	int	*count;
+/*	int	*hits;
+/*
+/*	void	tlsmgrmem_flush()
+/*	#endif
+/* DESCRIPTION
+/*	tlsmgrmem_disable() disables the in-memory TLS session cache.
+/*
+/*	tlsmgrmem_status() reports whether the cache is enabled, the
+/*	number of entries in the cache, and the number of cache hits.
+/*	If any of the return pointers are null, that item is not reported.
+/*
+/*	tlsmgrmem_flush() flushes any cached data and frees the cache.
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*
+/*	Viktor Dukhovni
+/*--*/
+
+#include <sys_defs.h>
+
+#ifdef USE_TLS
+#include <htable.h>
+#include <vstring.h>
+#include <tls_mgr.h>
+
+#include "tlsmgrmem.h"
+
+static HTABLE *tls_cache;
+static int cache_enabled = 1;
+static int cache_count;
+static int cache_hits;
+typedef void (*free_func) (void *);
+static free_func free_value = (free_func) vstring_free;
+
+void    tlsmgrmem_disable(void)
+{
+    cache_enabled = 0;
+}
+
+void    tlsmgrmem_flush(void)
+{
+    if (!tls_cache)
+	return;
+    htable_free(tls_cache, free_value);
+}
+
+void    tlsmgrmem_status(int *enabled, int *count, int *hits)
+{
+    if (enabled)
+	*enabled = cache_enabled;
+    if (count)
+	*count = cache_count;
+    if (hits)
+	*hits = cache_hits;
+}
+
+/* tls_mgr_* - Local cache and stubs that do not talk to the TLS manager */
+
+int     tls_mgr_seed(VSTRING *buf, int len)
+{
+    return (TLS_MGR_STAT_OK);
+}
+
+int     tls_mgr_policy(const char *unused_type, int *cachable, int *timeout)
+{
+    if (cache_enabled && tls_cache == 0)
+	tls_cache = htable_create(1);
+    *cachable = cache_enabled;
+    *timeout = TLS_SESSION_LIFEMIN;
+    return (TLS_MGR_STAT_OK);
+}
+
+int     tls_mgr_lookup(const char *unused_type, const char *key, VSTRING *buf)
+{
+    VSTRING *s;
+
+    if (tls_cache == 0)
+	return TLS_MGR_STAT_ERR;
+
+    if ((s = (VSTRING *) htable_find(tls_cache, key)) == 0)
+	return TLS_MGR_STAT_ERR;
+
+    vstring_memcpy(buf, vstring_str(s), VSTRING_LEN(s));
+
+    ++cache_hits;
+    return (TLS_MGR_STAT_OK);
+}
+
+int     tls_mgr_update(const char *unused_type, const char *key,
+		               const char *buf, ssize_t len)
+{
+    HTABLE_INFO *ent;
+    VSTRING *s;
+
+    if (tls_cache == 0)
+	return TLS_MGR_STAT_ERR;
+
+    if ((ent = htable_locate(tls_cache, key)) == 0) {
+	s = vstring_alloc(len);
+	ent = htable_enter(tls_cache, key, (void *) s);
+    } else {
+	s = (VSTRING *) ent->value;
+    }
+    vstring_memcpy(s, buf, len);
+
+    ++cache_count;
+    return (TLS_MGR_STAT_OK);
+}
+
+int     tls_mgr_delete(const char *unused_type, const char *key)
+{
+    if (tls_cache == 0)
+	return TLS_MGR_STAT_ERR;
+
+    if (htable_locate(tls_cache, key)) {
+	htable_delete(tls_cache, key, free_value);
+	--cache_count;
+    }
+    return (TLS_MGR_STAT_OK);
+}
+
+#endif
diff --git a/src/posttls-finger/tlsmgrmem.h b/src/posttls-finger/tlsmgrmem.h
new file mode 100644
index 0000000..706b206
--- /dev/null
+++ b/src/posttls-finger/tlsmgrmem.h
@@ -0,0 +1,28 @@
+/*++
+/* NAME
+/*	tlsmgrmem 3
+/* SUMMARY
+/*	Memory-based TLS manager interface for tlsfinger(1).
+/* SYNOPSIS
+/*	#include <tlsmgrmem.h>
+/* DESCRIPTION
+/* .nf
+
+ /* External interface. */
+
+extern void tlsmgrmem_disable(void);
+extern void tlsmgrmem_status(int *, int *, int *);
+extern void tlsmgrmem_flush(void);
+
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*
+/*	Viktor Dukhovni
+/*--*/