NB: big update - may break stuff. Please test!

 - (djm) OpenBSD CVS sync:
   - markus@cvs.openbsd.org  2001/02/03 03:08:38
     [auth-options.c auth-rh-rsa.c auth-rhosts.c auth.c canohost.c]
     [canohost.h servconf.c servconf.h session.c sshconnect1.c sshd.8]
     [sshd_config]
     make ReverseMappingCheck optional in sshd_config; ok djm@,dugsong@
   - markus@cvs.openbsd.org  2001/02/03 03:19:51
     [ssh.1 sshd.8 sshd_config]
     Skey is now called ChallengeResponse
   - markus@cvs.openbsd.org  2001/02/03 03:43:09
     [sshd.8]
     use no-pty option in .ssh/authorized_keys* if you need a 8-bit clean
     channel. note from Erik.Anggard@cygate.se (pr/1659)
   - stevesk@cvs.openbsd.org 2001/02/03 10:03:06
     [ssh.1]
     typos; ok markus@
   - djm@cvs.openbsd.org     2001/02/04 04:11:56
     [scp.1 sftp-server.c ssh.1 sshd.8 sftp-client.c sftp-client.h]
     [sftp-common.c sftp-common.h sftp-int.c sftp-int.h sftp.1 sftp.c]
     Basic interactive sftp client; ok theo@
 - (djm) Update RPM specs for new sftp binary
 - (djm) Update several bits for new optional reverse lookup stuff. I
   think I got them all.
diff --git a/servconf.c b/servconf.c
index 9f292b6..5fa41e0 100644
--- a/servconf.c
+++ b/servconf.c
@@ -10,7 +10,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: servconf.c,v 1.63 2001/01/22 23:06:39 markus Exp $");
+RCSID("$OpenBSD: servconf.c,v 1.64 2001/02/03 10:08:37 markus Exp $");
 
 #ifdef KRB4
 #include <krb.h>
@@ -92,6 +92,7 @@
 	options->max_startups_rate = -1;
 	options->max_startups = -1;
 	options->banner = NULL;
+	options->reverse_mapping_check = -1;
 }
 
 void
@@ -186,6 +187,8 @@
 		options->max_startups_rate = 100;		/* 100% */
 	if (options->max_startups_begin == -1)
 		options->max_startups_begin = options->max_startups;
+	if (options->reverse_mapping_check == -1)
+		options->reverse_mapping_check = 0;
 }
 
 /* Keyword tokens. */
@@ -208,7 +211,7 @@
 	sAllowUsers, sDenyUsers, sAllowGroups, sDenyGroups,
 	sIgnoreUserKnownHosts, sCiphers, sProtocol, sPidFile,
 	sGatewayPorts, sPubkeyAuthentication, sXAuthLocation, sSubsystem, sMaxStartups,
-	sBanner
+	sBanner, sReverseMappingCheck
 } ServerOpCodes;
 
 /* Textual representation of the tokens. */
@@ -268,6 +271,7 @@
 	{ "subsystem", sSubsystem },
 	{ "maxstartups", sMaxStartups },
 	{ "banner", sBanner },
+	{ "reversemappingcheck", sReverseMappingCheck },
 	{ NULL, 0 }
 };
 
@@ -577,6 +581,10 @@
 			intptr = &options->gateway_ports;
 			goto parse_flag;
 
+		case sReverseMappingCheck:
+			intptr = &options->reverse_mapping_check;
+			goto parse_flag;
+
 		case sLogFacility:
 			intptr = (int *) &options->log_facility;
 			arg = strdelim(&cp);