Initial integration of a much cleaned up libwrap.

23 files changed, 3450 insertions, 0 deletions

diff --git a/lib/libwrap/Makefile b/lib/libwrap/Makefile
new file mode 100644
index 00000000000..14fb6b27ce2
--- /dev/null
+++ b/lib/libwrap/Makefile
@@ -0,0 +1,32 @@
+#	$OpenBSD: Makefile,v 1.1 1997/02/26 03:06:49 downsj Exp $
+
+LIB=	wrap
+SRCS=	hosts_access.c options.c shell_cmd.c rfc931.c eval.c \
+	hosts_ctl.c refuse.c percent_x.c clean_exit.c \
+	fix_options.c socket.c update.c misc.c \
+	diag.c percent_m.c
+HDRS=	tcpd.h
+
+# Configuration options for libwrap.
+CFLAGS+=-DPROCESS_OPTIONS -DFACILITY=LOG_AUTH -DSEVERITY=LOG_INFO \
+	-DRFC931_TIMEOUT=10 -DHOSTS_ACCESS -DALWAYS_HOSTNAME \
+	-DHOSTS_DENY=\"/etc/hosts.deny\" -DHOSTS_ALLOW=\"/etc/hosts.allow\" \
+	-DNETGROUP -DSYS_ERRLIST_DEFINED
+
+MAN=	hosts_access.3 hosts_access.5 hosts_options.5
+MLINKS+=hosts_access.5 hosts.allow.5
+MLINKS+=hosts_access.5 hosts.deny.5
+MLINKS+=hosts_access.3 hosts_ctl.3
+MLINKS+=hosts_access.3 request_init.3
+MLINKS+=hosts_access.3 request_set.3
+
+includes:
+	@cd ${.CURDIR}; for i in $(HDRS); do \
+	    j="cmp -s $$i ${DESTDIR}/usr/include/$$i || \
+		${INSTALL} ${COPY} -o ${BINOWN} -g ${BINGRP} -m 444 $$i \
+		${DESTDIR}/usr/include"; \
+	    echo $$j; \
+	    eval "$$j"; \
+	done
+
+.include <bsd.lib.mk>
diff --git a/lib/libwrap/clean_exit.c b/lib/libwrap/clean_exit.c
new file mode 100644
index 00000000000..3e6f3815462
--- /dev/null
+++ b/lib/libwrap/clean_exit.c
@@ -0,0 +1,47 @@
+/*	$OpenBSD: clean_exit.c,v 1.1 1997/02/26 03:06:50 downsj Exp $	*/
+
+/*
+  * clean_exit() cleans up and terminates the program. It should be called
+  * instead of exit() when for some reason the real network daemon will not or
+  * cannot be run. Reason: in the case of a datagram-oriented service we must
+  * discard the not-yet received data from the client. Otherwise, inetd will
+  * see the same datagram again and again, and go into a loop.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) clean_exit.c 1.4 94/12/28 17:42:19";
+#else
+static char rcsid[] = "$OpenBSD: clean_exit.c,v 1.1 1997/02/26 03:06:50 downsj Exp $";
+#endif
+#endif
+
+#include <stdio.h>
+#include <unistd.h>
+
+#include "tcpd.h"
+
+/* clean_exit - clean up and exit */
+
+void    clean_exit(request)
+struct request_info *request;
+{
+
+    /*
+     * In case of unconnected protocols we must eat up the not-yet received
+     * data or inetd will loop.
+     */
+
+    if (request->sink)
+	request->sink(request->fd);
+
+    /*
+     * Be kind to the inetd. We already reported the problem via the syslogd,
+     * and there is no need for additional garbage in the logfile.
+     */
+
+    sleep(5);
+    exit(0);
+}
diff --git a/lib/libwrap/diag.c b/lib/libwrap/diag.c
new file mode 100644
index 00000000000..ed8d064ed56
--- /dev/null
+++ b/lib/libwrap/diag.c
@@ -0,0 +1,75 @@
+/*	$OpenBSD: diag.c,v 1.1 1997/02/26 03:06:50 downsj Exp $	*/
+
+ /*
+  * Routines to report various classes of problems. Each report is decorated
+  * with the current context (file name and line number), if available.
+  * 
+  * tcpd_warn() reports a problem and proceeds.
+  * 
+  * tcpd_jump() reports a problem and jumps.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) diag.c 1.1 94/12/28 17:42:20";
+#else
+static char rcsid[] = "$OpenBSD: diag.c,v 1.1 1997/02/26 03:06:50 downsj Exp $";
+#endif
+#endif
+
+/* System libraries */
+
+#include <syslog.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <setjmp.h>
+
+/* Local stuff */
+
+#include "tcpd.h"
+
+struct tcpd_context tcpd_context;
+jmp_buf tcpd_buf;
+
+/* tcpd_diag - centralize error reporter */
+
+static void tcpd_diag(severity, tag, format, ap)
+int     severity;
+char   *tag;
+char   *format;
+va_list ap;
+{
+    char    fmt[BUFSIZ];
+
+    if (tcpd_context.file)
+	sprintf(fmt, "%s: %s, line %d: %s",
+		tag, tcpd_context.file, tcpd_context.line, format);
+    else
+	sprintf(fmt, "%s: %s", tag, format);
+    vsyslog(severity, fmt, ap);
+}
+
+/* tcpd_warn - report problem of some sort and proceed */
+
+void    VARARGS(tcpd_warn, char *, format)
+{
+    va_list ap;
+
+    VASTART(ap, char *, format);
+    tcpd_diag(LOG_ERR, "warning", format, ap);
+    VAEND(ap);
+}
+
+/* tcpd_jump - report serious problem and jump */
+
+void    VARARGS(tcpd_jump, char *, format)
+{
+    va_list ap;
+
+    VASTART(ap, char *, format);
+    tcpd_diag(LOG_ERR, "error", format, ap);
+    VAEND(ap);
+    longjmp(tcpd_buf, AC_ERROR);
+}
diff --git a/lib/libwrap/eval.c b/lib/libwrap/eval.c
new file mode 100644
index 00000000000..ef8bc4562aa
--- /dev/null
+++ b/lib/libwrap/eval.c
@@ -0,0 +1,142 @@
+/*	$OpenBSD: eval.c,v 1.1 1997/02/26 03:06:50 downsj Exp $	*/
+
+ /*
+  * Routines for controlled evaluation of host names, user names, and so on.
+  * They are, in fact, wrappers around the functions that are specific for
+  * the sockets or TLI programming interfaces. The request_info and host_info
+  * structures are used for result cacheing.
+  * 
+  * These routines allows us to postpone expensive operations until their
+  * results are really needed. Examples are hostname lookups and double
+  * checks, or username lookups. Information that cannot be retrieved is
+  * given the value "unknown" ("paranoid" in case of hostname problems).
+  * 
+  * When ALWAYS_HOSTNAME is off, hostname lookup is done only when required by
+  * tcpd paranoid mode, by access control patterns, or by %letter expansions.
+  * 
+  * When ALWAYS_RFC931 mode is off, user lookup is done only when required by
+  * access control patterns or %letter expansions.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) eval.c 1.3 95/01/30 19:51:45";
+#else
+static char rcsid[] = "$OpenBSD: eval.c,v 1.1 1997/02/26 03:06:50 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <stdio.h>
+#include <string.h>
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+ /*
+  * When a string has the value STRING_UNKNOWN, it means: don't bother, I
+  * tried to look up the data but it was unavailable for some reason. When a
+  * host name has the value STRING_PARANOID it means there was a name/address
+  * conflict.
+  */
+char    unknown[] = STRING_UNKNOWN;
+char    paranoid[] = STRING_PARANOID;
+
+/* eval_user - look up user name */
+
+char   *eval_user(request)
+struct request_info *request;
+{
+    if (request->user[0] == 0) {
+	strcpy(request->user, unknown);
+	if (request->sink == 0 && request->client->sin && request->server->sin)
+	    rfc931(request->client->sin, request->server->sin, request->user);
+    }
+    return (request->user);
+}
+
+/* eval_hostaddr - look up printable address */
+
+char   *eval_hostaddr(host)
+struct host_info *host;
+{
+    if (host->addr[0] == 0) {
+	strcpy(host->addr, unknown);
+	if (host->request->hostaddr != 0)
+	    host->request->hostaddr(host);
+    }
+    return (host->addr);
+}
+
+/* eval_hostname - look up host name */
+
+char   *eval_hostname(host)
+struct host_info *host;
+{
+    if (host->name[0] == 0) {
+	strcpy(host->name, unknown);
+	if (host->request->hostname != 0)
+	    host->request->hostname(host);
+    }
+    return (host->name);
+}
+
+/* eval_hostinfo - return string with host name (preferred) or address */
+
+char   *eval_hostinfo(host)
+struct host_info *host;
+{
+    char   *hostname;
+
+#ifndef ALWAYS_HOSTNAME				/* no implicit host lookups */
+    if (host->name[0] == 0)
+	return (eval_hostaddr(host));
+#endif
+    hostname = eval_hostname(host);
+    if (HOSTNAME_KNOWN(hostname)) {
+	return (host->name);
+    } else {
+	return (eval_hostaddr(host));
+    }
+}
+
+/* eval_client - return string with as much about the client as we know */
+
+char   *eval_client(request)
+struct request_info *request;
+{
+    static char both[2 * STRING_LENGTH];
+    char   *hostinfo = eval_hostinfo(request->client);
+
+#ifndef ALWAYS_RFC931				/* no implicit user lookups */
+    if (request->user[0] == 0)
+	return (hostinfo);
+#endif
+    if (STR_NE(eval_user(request), unknown)) {
+	sprintf(both, "%s@%s", request->user, hostinfo);
+	return (both);
+    } else {
+	return (hostinfo);
+    }
+}
+
+/* eval_server - return string with as much about the server as we know */
+
+char   *eval_server(request)
+struct request_info *request;
+{
+    static char both[2 * STRING_LENGTH];
+    char   *host = eval_hostinfo(request->server);
+    char   *daemon = eval_daemon(request);
+
+    if (STR_NE(host, unknown)) {
+	sprintf(both, "%s@%s", daemon, host);
+	return (both);
+    } else {
+	return (daemon);
+    }
+}
diff --git a/lib/libwrap/fix_options.c b/lib/libwrap/fix_options.c
new file mode 100644
index 00000000000..619f1469952
--- /dev/null
+++ b/lib/libwrap/fix_options.c
@@ -0,0 +1,132 @@
+/*	$OpenBSD: fix_options.c,v 1.1 1997/02/26 03:06:51 downsj Exp $	*/
+
+ /*
+  * Routine to disable IP-level socket options. This code was taken from 4.4BSD
+  * rlogind and kernel source, but all mistakes in it are my fault.
+  *
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) fix_options.c 1.4 97/02/12 02:13:22";
+#else
+static char rcsid[] = "$OpenBSD: fix_options.c,v 1.1 1997/02/26 03:06:51 downsj Exp $";
+#endif
+#endif
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/in_systm.h>
+#include <netinet/ip.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <syslog.h>
+
+#ifndef IPOPT_OPTVAL
+#define IPOPT_OPTVAL	0
+#define IPOPT_OLEN	1
+#endif
+
+#include "tcpd.h"
+
+#define BUFFER_SIZE	512		/* Was: BUFSIZ */
+
+/* fix_options - get rid of IP-level socket options */
+
+void
+fix_options(request)
+struct request_info *request;
+{
+#ifdef IP_OPTIONS
+    unsigned char optbuf[BUFFER_SIZE / 3], *cp;
+    char    lbuf[BUFFER_SIZE], *lp;
+    int     optsize = sizeof(optbuf), ipproto;
+    struct protoent *ip;
+    int     fd = request->fd;
+    unsigned int opt;
+    int     optlen;
+    unsigned char *first_option = optbuf;
+
+    if ((ip = getprotobyname("ip")) != 0)
+	ipproto = ip->p_proto;
+    else
+	ipproto = IPPROTO_IP;
+
+    if (getsockopt(fd, ipproto, IP_OPTIONS, (char *) optbuf, &optsize) == 0
+	&& optsize != 0) {
+
+	/*
+	 * Horror! 4.[34] BSD getsockopt() prepends the first-hop destination
+	 * address to the result IP options list when source routing options
+	 * are present (see <netinet/ip_var.h>), but produces no output for
+	 * other IP options. Solaris 2.x getsockopt() does produce output for
+	 * non-routing IP options, and uses the same format as BSD even when
+	 * the space for the destination address is unused. However, we must
+	 * be prepared to deal with systems that return the options only. The
+	 * code below does the right thing with 4.[34]BSD derivatives and
+	 * Solaris 2, but may occasionally miss source routing options on
+	 * incompatible systems such as Linux. Their choice.
+	 */
+#define ADDR_LEN sizeof(struct in_addr)
+
+	for (cp = optbuf + ADDR_LEN; cp < optbuf + optsize; cp++) {
+	    opt = cp[IPOPT_OPTVAL];
+	    if (opt != IPOPT_NOP) {
+		if (opt == IPOPT_RR
+		    || opt == IPOPT_TS
+		    || opt == IPOPT_SECURITY
+		    || opt == IPOPT_LSRR
+		    || opt == IPOPT_SATID
+		    || opt == IPOPT_SSRR)
+		    first_option = cp;
+		break;
+	    }
+	}
+
+	/*
+	 * Look for source routing options. Drop the connection when one is
+	 * found. Just wiping the IP options is insufficient: we would still
+	 * help the attacker by providing a real TCP sequence number, and the
+	 * attacker would still be able to send packets (blind spoofing). I
+	 * discussed this attack with Niels Provos, half a year before the
+	 * attack was described in open mailing lists.
+	 * 
+	 * It would be cleaner to just return a yes/no reply and let the caller
+	 * decide how to deal with it. Resident servers should not terminate.
+	 * However I am not prepared to make changes to internal interfaces
+	 * on short notice.
+	 */
+	for (cp = first_option; cp < optbuf + optsize; cp += optlen) {
+	    opt = cp[IPOPT_OPTVAL];
+	    if (opt == IPOPT_LSRR || opt == IPOPT_SSRR) {
+		syslog(LOG_WARNING,
+		   "refused connect from %s with IP source routing options",
+		       eval_client(request));
+		clean_exit(request);
+	    }
+	    if (opt == IPOPT_EOL)
+		break;
+	    if (opt == IPOPT_NOP) {
+		optlen = 1;
+	    } else {
+		optlen = cp[IPOPT_OLEN];
+		if (optlen <= 0)		/* Do not loop! */
+		    break;
+	    }
+	}
+	lp = lbuf;
+	for (cp = optbuf; optsize > 0; cp++, optsize--, lp += 3)
+	    sprintf(lp, " %2.2x", *cp);
+	syslog(LOG_NOTICE,
+	       "connect from %s with IP options (ignored):%s",
+	       eval_client(request), lbuf);
+	if (setsockopt(fd, ipproto, IP_OPTIONS, (char *) 0, optsize) != 0) {
+	    syslog(LOG_ERR, "setsockopt IP_OPTIONS NULL: %m");
+	    clean_exit(request);
+	}
+    }
+#endif
+}
diff --git a/lib/libwrap/hosts_access.3 b/lib/libwrap/hosts_access.3
new file mode 100644
index 00000000000..2614dbac21b
--- /dev/null
+++ b/lib/libwrap/hosts_access.3
@@ -0,0 +1,94 @@
+.\"	$OpenBSD: hosts_access.3,v 1.1 1997/02/26 03:06:51 downsj Exp $
+.TH HOSTS_ACCESS 3
+.SH NAME
+hosts_access, hosts_ctl, request_init, request_set \- access control library
+.SH SYNOPSIS
+.nf
+#include "tcpd.h"
+
+extern int allow_severity;
+extern int deny_severity;
+
+struct request_info *request_init(request, key, value, ..., 0)
+struct request_info *request;
+
+struct request_info *request_set(request, key, value, ..., 0)
+struct request_info *request;
+
+int hosts_access(request)
+struct request_info *request;
+
+int hosts_ctl(daemon, client_name, client_addr, client_user)
+char *daemon;
+char *client_name;
+char *client_addr;
+char *client_user;
+.fi
+.SH DESCRIPTION
+The routines described in this document are part of the \fIlibwrap.a\fR
+library. They implement a rule-based access control language with
+optional shell commands that are executed when a rule fires.
+.PP
+request_init() initializes a structure with information about a client
+request. request_set() updates an already initialized request
+structure. Both functions take a variable-length list of key-value
+pairs and return their first argument.  The argument lists are
+terminated with a zero key value. All string-valued arguments are
+copied. The expected keys (and corresponding value types) are:
+.IP "RQ_FILE (int)"
+The file descriptor associated with the request.
+.IP "RQ_CLIENT_NAME (char *)"
+The client host name.
+.IP "RQ_CLIENT_ADDR (char *)"
+A printable representation of the client network address.
+.IP "RQ_CLIENT_SIN (struct sockaddr_in *)"
+An internal representation of the client network address and port.  The
+contents of the structure are not copied.
+.IP "RQ_SERVER_NAME (char *)"
+The hostname associated with the server endpoint address.
+.IP "RQ_SERVER_ADDR (char *)"
+A printable representation of the server endpoint address.
+.IP "RQ_SERVER_SIN (struct sockaddr_in *)"
+An internal representation of the server endpoint address and port.
+The contents of the structure are not copied.
+.IP "RQ_DAEMON (char *)"
+The name of the daemon process running on the server host.
+.IP "RQ_USER (char *)"
+The name of the user on whose behalf the client host makes the request.
+.PP
+hosts_access() consults the access control tables described in the
+\fIhosts_access(5)\fR manual page.  When internal endpoint information
+is available, host names and client user names are looked up on demand,
+using the request structure as a cache.  hosts_access() returns zero if
+access should be denied.
+.PP
+hosts_ctl() is a wrapper around the request_init() and hosts_access()
+routines with a perhaps more convenient interface (though it does not
+pass on enough information to support automated client username
+lookups).  The client host address, client host name and username
+arguments should contain valid data or STRING_UNKNOWN.  hosts_ctl()
+returns zero if access should be denied.
+.PP
+The \fIallow_severity\fR and \fIdeny_severity\fR variables determine
+how accepted and rejected requests may be logged. They must be provided
+by the caller and may be modified by rules in the access control
+tables.
+.SH DIAGNOSTICS
+Problems are reported via the syslog daemon.
+.SH SEE ALSO
+hosts_access(5), format of the access control tables.
+hosts_options(5), optional extensions to the base language.
+.SH FILES
+/etc/hosts.allow, /etc/hosts.deny, access control tables.
+.SH BUGS
+hosts_access() uses the strtok() library function. This may interfere
+with other code that relies on strtok().
+.SH AUTHOR
+.na
+.nf
+Wietse Venema (wietse@wzv.win.tue.nl)
+Department of Mathematics and Computing Science
+Eindhoven University of Technology
+Den Dolech 2, P.O. Box 513, 
+5600 MB Eindhoven, The Netherlands
+\" @(#) hosts_access.3 1.8 96/02/11 17:01:26
diff --git a/lib/libwrap/hosts_access.5 b/lib/libwrap/hosts_access.5
new file mode 100644
index 00000000000..feab610e485
--- /dev/null
+++ b/lib/libwrap/hosts_access.5
@@ -0,0 +1,379 @@
+.\"	$OpenBSD: hosts_access.5,v 1.1 1997/02/26 03:06:52 downsj Exp $
+.TH HOSTS_ACCESS 5
+.SH NAME
+hosts_access \- format of host access control files
+.SH DESCRIPTION
+This manual page describes a simple access control language that is
+based on client (host name/address, user name), and server (process
+name, host name/address) patterns.  Examples are given at the end. The
+impatient reader is encouraged to skip to the EXAMPLES section for a
+quick introduction.
+.PP
+An extended version of the access control language is described in the
+\fIhosts_options\fR(5) document. The extensions are turned on at
+program build time by building with -DPROCESS_OPTIONS.
+.PP
+In the following text, \fIdaemon\fR is the the process name of a
+network daemon process, and \fIclient\fR is the name and/or address of
+a host requesting service. Network daemon process names are specified
+in the inetd configuration file.
+.SH ACCESS CONTROL FILES
+The access control software consults two files. The search stops
+at the first match:
+.IP \(bu
+Access will be granted when a (daemon,client) pair matches an entry in
+the \fI/etc/hosts.allow\fR file.
+.IP \(bu
+Otherwise, access will be denied when a (daemon,client) pair matches an
+entry in the \fI/etc/hosts.deny\fR file.
+.IP \(bu
+Otherwise, access will be granted.
+.PP
+A non-existing access control file is treated as if it were an empty
+file. Thus, access control can be turned off by providing no access
+control files.
+.SH ACCESS CONTROL RULES
+Each access control file consists of zero or more lines of text.  These
+lines are processed in order of appearance. The search terminates when a
+match is found.
+.IP \(bu
+A newline character is ignored when it is preceded by a backslash
+character. This permits you to break up long lines so that they are
+easier to edit.
+.IP \(bu
+Blank lines or lines that begin with a `#\' character are ignored.
+This permits you to insert comments and whitespace so that the tables
+are easier to read.
+.IP \(bu
+All other lines should satisfy the following format, things between []
+being optional:
+.sp
+.ti +3
+daemon_list : client_list [ : shell_command ]
+.PP
+\fIdaemon_list\fR is a list of one or more daemon process names
+(argv[0] values) or wildcards (see below).  
+.PP
+\fIclient_list\fR is a list
+of one or more host names, host addresses, patterns or wildcards (see
+below) that will be matched against the client host name or address.
+.PP
+The more complex forms \fIdaemon@host\fR and \fIuser@host\fR are
+explained in the sections on server endpoint patterns and on client
+username lookups, respectively.
+.PP
+List elements should be separated by blanks and/or commas.  
+.PP
+With the exception of NIS (YP) netgroup lookups, all access control
+checks are case insensitive.
+.ne 4
+.SH PATTERNS
+The access control language implements the following patterns:
+.IP \(bu
+A string that begins with a `.\' character. A host name is matched if
+the last components of its name match the specified pattern.  For
+example, the pattern `.tue.nl\' matches the host name
+`wzv.win.tue.nl\'.
+.IP \(bu
+A string that ends with a `.\' character. A host address is matched if
+its first numeric fields match the given string.  For example, the
+pattern `131.155.\' matches the address of (almost) every host on the
+Eind\%hoven University network (131.155.x.x).
+.IP \(bu
+A string that begins with an `@\' character is treated as an NIS
+(formerly YP) netgroup name. A host name is matched if it is a host
+member of the specified netgroup. Netgroup matches are not supported
+for daemon process names or for client user names.
+.IP \(bu
+An expression of the form `n.n.n.n/m.m.m.m\' is interpreted as a
+`net/mask\' pair. A host address is matched if `net\' is equal to the
+bitwise AND of the address and the `mask\'. For example, the net/mask
+pattern `131.155.72.0/255.255.254.0\' matches every address in the
+range `131.155.72.0\' through `131.155.73.255\'.
+.SH WILDCARDS
+The access control language supports explicit wildcards:
+.IP ALL
+The universal wildcard, always matches.
+.IP LOCAL
+Matches any host whose name does not contain a dot character.
+.IP UNKNOWN
+Matches any user whose name is unknown, and matches any host whose name
+\fIor\fR address are unknown.  This pattern should be used with care:
+host names may be unavailable due to temporary name server problems. A
+network address will be unavailable when the software cannot figure out
+what type of network it is talking to.
+.IP KNOWN
+Matches any user whose name is known, and matches any host whose name
+\fIand\fR address are known. This pattern should be used with care:
+host names may be unavailable due to temporary name server problems.  A
+network address will be unavailable when the software cannot figure out
+what type of network it is talking to.
+.IP PARANOID
+Matches any host whose name does not match its address.  When tcpd is
+built with -DPARANOID (default mode), it drops requests from such
+clients even before looking at the access control tables.  Build
+without -DPARANOID when you want more control over such requests.
+.ne 6
+.SH OPERATORS
+.IP EXCEPT
+Intended use is of the form: `list_1 EXCEPT list_2\'; this construct
+matches anything that matches \fIlist_1\fR unless it matches
+\fIlist_2\fR.  The EXCEPT operator can be used in daemon_lists and in
+client_lists. The EXCEPT operator can be nested: if the control
+language would permit the use of parentheses, `a EXCEPT b EXCEPT c\'
+would parse as `(a EXCEPT (b EXCEPT c))\'.
+.br
+.ne 6
+.SH SHELL COMMANDS
+If the first-matched access control rule contains a shell command, that
+command is subjected to %<letter> substitutions (see next section).
+The result is executed by a \fI/bin/sh\fR child process with standard
+input, output and error connected to \fI/dev/null\fR.  Specify an `&\'
+at the end of the command if you do not want to wait until it has
+completed.
+.PP
+Shell commands should not rely on the PATH setting of the inetd.
+Instead, they should use absolute path names, or they should begin with
+an explicit PATH=whatever statement.
+.PP
+The \fIhosts_options\fR(5) document describes an alternative language
+that uses the shell command field in a different and incompatible way.
+.SH % EXPANSIONS
+The following expansions are available within shell commands:
+.IP "%a (%A)"
+The client (server) host address.
+.IP %c
+Client information: user@host, user@address, a host name, or just an
+address, depending on how much information is available.
+.IP %d
+The daemon process name (argv[0] value).
+.IP "%h (%H)"
+The client (server) host name or address, if the host name is
+unavailable.
+.IP "%n (%N)"
+The client (server) host name (or "unknown" or "paranoid").
+.IP %p
+The daemon process id.
+.IP %s
+Server information: daemon@host, daemon@address, or just a daemon name,
+depending on how much information is available.
+.IP %u
+The client user name (or "unknown").
+.IP %%
+Expands to a single `%\' character.
+.PP
+Characters in % expansions that may confuse the shell are replaced by
+underscores.
+.SH SERVER ENDPOINT PATTERNS
+In order to distinguish clients by the network address that they
+connect to, use patterns of the form:
+.sp
+.ti +3
+process_name@host_pattern : client_list ...
+.sp
+Patterns like these can be used when the machine has different internet
+addresses with different internet hostnames.  Service providers can use
+this facility to offer FTP, GOPHER or WWW archives with internet names
+that may even belong to different organizations. See also the `twist'
+option in the hosts_options(5) document. Some systems (Solaris,
+FreeBSD) can have more than one internet address on one physical
+interface; with other systems you may have to resort to SLIP or PPP
+pseudo interfaces that live in a dedicated network address space.
+.sp
+The host_pattern obeys the same syntax rules as host names and
+addresses in client_list context. Usually, server endpoint information
+is available only with connection-oriented services.
+.SH CLIENT USERNAME LOOKUP
+When the client host supports the RFC 931 protocol or one of its
+descendants (TAP, IDENT, RFC 1413) the wrapper programs can retrieve
+additional information about the owner of a connection. Client username
+information, when available, is logged together with the client host
+name, and can be used to match patterns like:
+.PP
+.ti +3
+daemon_list : ... user_pattern@host_pattern ...
+.PP
+The daemon wrappers can be configured at compile time to perform
+rule-driven username lookups (default) or to always interrogate the
+client host.  In the case of rule-driven username lookups, the above
+rule would cause username lookup only when both the \fIdaemon_list\fR
+and the \fIhost_pattern\fR match. 
+.PP
+A user pattern has the same syntax as a daemon process pattern, so the
+same wildcards apply (netgroup membership is not supported).  One
+should not get carried away with username lookups, though.
+.IP \(bu
+The client username information cannot be trusted when it is needed
+most, i.e. when the client system has been compromised.  In general,
+ALL and (UN)KNOWN are the only user name patterns that make sense.
+.IP \(bu
+Username lookups are possible only with TCP-based services, and only
+when the client host runs a suitable daemon; in all other cases the
+result is "unknown".
+.IP \(bu
+A well-known UNIX kernel bug may cause loss of service when username
+lookups are blocked by a firewall. The wrapper README document
+describes a procedure to find out if your kernel has this bug.
+.IP \(bu
+Username lookups may cause noticeable delays for non-UNIX users.  The
+default timeout for username lookups is 10 seconds: too short to cope
+with slow networks, but long enough to irritate PC users.
+.PP
+Selective username lookups can alleviate the last problem. For example,
+a rule like:
+.PP
+.ti +3
+daemon_list : @pcnetgroup ALL@ALL
+.PP
+would match members of the pc netgroup without doing username lookups,
+but would perform username lookups with all other systems.
+.SH DETECTING ADDRESS SPOOFING ATTACKS
+A flaw in the sequence number generator of many TCP/IP implementations
+allows intruders to easily impersonate trusted hosts and to break in
+via, for example, the remote shell service.  The IDENT (RFC931 etc.)
+service can be used to detect such and other host address spoofing
+attacks.
+.PP
+Before accepting a client request, the wrappers can use the IDENT
+service to find out that the client did not send the request at all.
+When the client host provides IDENT service, a negative IDENT lookup
+result (the client matches `UNKNOWN@host') is strong evidence of a host
+spoofing attack.
+.PP
+A positive IDENT lookup result (the client matches `KNOWN@host') is
+less trustworthy. It is possible for an intruder to spoof both the
+client connection and the IDENT lookup, although doing so is much
+harder than spoofing just a client connection. It may also be that
+the client\'s IDENT server is lying.
+.PP
+Note: IDENT lookups don\'t work with UDP services. 
+.SH EXAMPLES
+The language is flexible enough that different types of access control
+policy can be expressed with a minimum of fuss. Although the language
+uses two access control tables, the most common policies can be
+implemented with one of the tables being trivial or even empty.
+.PP
+When reading the examples below it is important to realize that the
+allow table is scanned before the deny table, that the search
+terminates when a match is found, and that access is granted when no
+match is found at all.
+.PP
+The examples use host and domain names. They can be improved by
+including address and/or network/netmask information, to reduce the
+impact of temporary name server lookup failures.
+.SH MOSTLY CLOSED
+In this case, access is denied by default. Only explicitly authorized
+hosts are permitted access. 
+.PP
+The default policy (no access) is implemented with a trivial deny
+file:
+.PP
+.ne 2
+/etc/hosts.deny: 
+.in +3
+ALL: ALL
+.PP
+This denies all service to all hosts, unless they are permitted access
+by entries in the allow file.
+.PP
+The explicitly authorized hosts are listed in the allow file.
+For example:
+.PP
+.ne 2
+/etc/hosts.allow: 
+.in +3
+ALL: LOCAL @some_netgroup
+.br
+ALL: .foobar.edu EXCEPT terminalserver.foobar.edu
+.PP
+The first rule permits access from hosts in the local domain (no `.\'
+in the host name) and from members of the \fIsome_netgroup\fP
+netgroup.  The second rule permits access from all hosts in the
+\fIfoobar.edu\fP domain (notice the leading dot), with the exception of
+\fIterminalserver.foobar.edu\fP.
+.SH MOSTLY OPEN
+Here, access is granted by default; only explicitly specified hosts are
+refused service. 
+.PP
+The default policy (access granted) makes the allow file redundant so
+that it can be omitted.  The explicitly non-authorized hosts are listed
+in the deny file. For example:
+.PP
+/etc/hosts.deny:
+.in +3
+ALL: some.host.name, .some.domain
+.br
+ALL EXCEPT in.fingerd: other.host.name, .other.domain
+.PP
+The first rule denies some hosts and domains all services; the second
+rule still permits finger requests from other hosts and domains.
+.SH BOOBY TRAPS
+The next example permits tftp requests from hosts in the local domain
+(notice the leading dot).  Requests from any other hosts are denied.
+Instead of the requested file, a finger probe is sent to the offending
+host. The result is mailed to the superuser.
+.PP
+.ne 2
+/etc/hosts.allow:
+.in +3
+.nf
+in.tftpd: LOCAL, .my.domain
+.PP
+.ne 2
+/etc/hosts.deny:
+.in +3
+.nf
+in.tftpd: ALL: (/some/where/safe_finger -l @%h | \\
+	/usr/ucb/mail -s %d-%h root) &
+.fi
+.PP
+The safe_finger command comes with the tcpd wrapper and should be
+installed in a suitable place. It limits possible damage from data sent
+by the remote finger server.  It gives better protection than the
+standard finger command.
+.PP
+The expansion of the %h (client host) and %d (service name) sequences
+is described in the section on shell commands.
+.PP
+Warning: do not booby-trap your finger daemon, unless you are prepared
+for infinite finger loops.
+.PP
+On network firewall systems this trick can be carried even further.
+The typical network firewall only provides a limited set of services to
+the outer world. All other services can be "bugged" just like the above
+tftp example. The result is an excellent early-warning system.
+.br
+.ne 4
+.SH DIAGNOSTICS
+An error is reported when a syntax error is found in a host access
+control rule; when the length of an access control rule exceeds the
+capacity of an internal buffer; when an access control rule is not
+terminated by a newline character; when the result of %<letter>
+expansion would overflow an internal buffer; when a system call fails
+that shouldn\'t.  All problems are reported via the syslog daemon.
+.SH FILES
+.na
+.nf
+/etc/hosts.allow, (daemon,client) pairs that are granted access.
+/etc/hosts.deny, (daemon,client) pairs that are denied access.
+.ad
+.fi
+.SH SEE ALSO
+.nf
+tcpd(8) tcp/ip daemon wrapper program.
+tcpdchk(8), tcpdmatch(8), test programs.
+.SH BUGS
+If a name server lookup times out, the host name will not be available
+to the access control software, even though the host is registered.
+.PP
+Domain name server lookups are case insensitive; NIS (formerly YP)
+netgroup lookups are case sensitive.
+.SH AUTHOR
+.na
+.nf
+Wietse Venema (wietse@wzv.win.tue.nl)
+Department of Mathematics and Computing Science
+Eindhoven University of Technology
+Den Dolech 2, P.O. Box 513, 
+5600 MB Eindhoven, The Netherlands
+\" @(#) hosts_access.5 1.20 95/01/30 19:51:46
diff --git a/lib/libwrap/hosts_access.c b/lib/libwrap/hosts_access.c
new file mode 100644
index 00000000000..bb9ca0e4128
--- /dev/null
+++ b/lib/libwrap/hosts_access.c
@@ -0,0 +1,339 @@
+/*	$OpenBSD: hosts_access.c,v 1.1 1997/02/26 03:06:52 downsj Exp $	*/
+
+ /*
+  * This module implements a simple access control language that is based on
+  * host (or domain) names, NIS (host) netgroup names, IP addresses (or
+  * network numbers) and daemon process names. When a match is found the
+  * search is terminated, and depending on whether PROCESS_OPTIONS is defined,
+  * a list of options is executed or an optional shell command is executed.
+  * 
+  * Host and user names are looked up on demand, provided that suitable endpoint
+  * information is available as sockaddr_in structures or TLI netbufs. As a
+  * side effect, the pattern matching process may change the contents of
+  * request structure fields.
+  * 
+  * Diagnostics are reported through syslog(3).
+  * 
+  * Compile with -DNETGROUP if your library provides support for netgroups.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) hosts_access.c 1.21 97/02/12 02:13:22";
+#else
+static char rcsid[] = "$OpenBSD: hosts_access.c,v 1.1 1997/02/26 03:06:52 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <stdio.h>
+#include <syslog.h>
+#include <ctype.h>
+#include <errno.h>
+#include <setjmp.h>
+#include <string.h>
+#ifdef NETGROUP
+#include <netgroup.h>
+#endif
+
+extern int errno;
+
+#ifndef	INADDR_NONE
+#define	INADDR_NONE	(-1)		/* XXX should be 0xffffffff */
+#endif
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+/* Error handling. */
+
+extern jmp_buf tcpd_buf;
+
+/* Delimiters for lists of daemons or clients. */
+
+static char sep[] = ", \t\r\n";
+
+/* Constants to be used in assignments only, not in comparisons... */
+
+#define	YES		1
+#define	NO		0
+
+ /*
+  * These variables are globally visible so that they can be redirected in
+  * verification mode.
+  */
+
+char   *hosts_allow_table = HOSTS_ALLOW;
+char   *hosts_deny_table = HOSTS_DENY;
+int     hosts_access_verbose = 0;
+
+ /*
+  * In a long-running process, we are not at liberty to just go away.
+  */
+
+int     resident = (-1);		/* -1, 0: unknown; +1: yes */
+
+/* Forward declarations. */
+
+static int table_match();
+static int list_match();
+static int server_match();
+static int client_match();
+static int host_match();
+static int string_match();
+static int masked_match();
+
+/* Size of logical line buffer. */
+
+#define	BUFLEN 2048
+
+/* hosts_access - host access control facility */
+
+int     hosts_access(request)
+struct request_info *request;
+{
+    int     verdict;
+
+    /*
+     * If the (daemon, client) pair is matched by an entry in the file
+     * /etc/hosts.allow, access is granted. Otherwise, if the (daemon,
+     * client) pair is matched by an entry in the file /etc/hosts.deny,
+     * access is denied. Otherwise, access is granted. A non-existent
+     * access-control file is treated as an empty file.
+     * 
+     * After a rule has been matched, the optional language extensions may
+     * decide to grant or refuse service anyway. Or, while a rule is being
+     * processed, a serious error is found, and it seems better to play safe
+     * and deny service. All this is done by jumping back into the
+     * hosts_access() routine, bypassing the regular return from the
+     * table_match() function calls below.
+     */
+
+    if (resident <= 0)
+	resident++;
+    verdict = setjmp(tcpd_buf);
+    if (verdict != 0)
+	return (verdict == AC_PERMIT);
+    if (table_match(hosts_allow_table, request))
+	return (YES);
+    if (table_match(hosts_deny_table, request))
+	return (NO);
+    return (YES);
+}
+
+/* table_match - match table entries with (daemon, client) pair */
+
+static int table_match(table, request)
+char   *table;
+struct request_info *request;
+{
+    FILE   *fp;
+    char    sv_list[BUFLEN];		/* becomes list of daemons */
+    char   *cl_list;			/* becomes list of clients */
+    char   *sh_cmd;			/* becomes optional shell command */
+    int     match = NO;
+    struct tcpd_context saved_context;
+
+    saved_context = tcpd_context;		/* stupid compilers */
+
+    /*
+     * Between the fopen() and fclose() calls, avoid jumps that may cause
+     * file descriptor leaks.
+     */
+
+    if ((fp = fopen(table, "r")) != 0) {
+	tcpd_context.file = table;
+	tcpd_context.line = 0;
+	while (match == NO && xgets(sv_list, sizeof(sv_list), fp) != 0) {
+	    if (sv_list[strlen(sv_list) - 1] != '\n') {
+		tcpd_warn("missing newline or line too long");
+		continue;
+	    }
+	    if (sv_list[0] == '#' || sv_list[strspn(sv_list, " \t\r\n")] == 0)
+		continue;
+	    if ((cl_list = split_at(sv_list, ':')) == 0) {
+		tcpd_warn("missing \":\" separator");
+		continue;
+	    }
+	    sh_cmd = split_at(cl_list, ':');
+	    match = list_match(sv_list, request, server_match)
+		&& list_match(cl_list, request, client_match);
+	}
+	(void) fclose(fp);
+    } else if (errno != ENOENT) {
+	tcpd_warn("cannot open %s: %m", table);
+    }
+    if (match) {
+	if (hosts_access_verbose > 1)
+	    syslog(LOG_DEBUG, "matched:  %s line %d",
+		   tcpd_context.file, tcpd_context.line);
+	if (sh_cmd) {
+#ifdef PROCESS_OPTIONS
+	    process_options(sh_cmd, request);
+#else
+	    char    cmd[BUFSIZ];
+	    shell_cmd(percent_x(cmd, sizeof(cmd), sh_cmd, request));
+#endif
+	}
+    }
+    tcpd_context = saved_context;
+    return (match);
+}
+
+/* list_match - match a request against a list of patterns with exceptions */
+
+static int list_match(list, request, match_fn)
+char   *list;
+struct request_info *request;
+int   (*match_fn) ();
+{
+    char   *tok;
+
+    /*
+     * Process tokens one at a time. We have exhausted all possible matches
+     * when we reach an "EXCEPT" token or the end of the list. If we do find
+     * a match, look for an "EXCEPT" list and recurse to determine whether
+     * the match is affected by any exceptions.
+     */
+
+    for (tok = strtok(list, sep); tok != 0; tok = strtok((char *) 0, sep)) {
+	if (STR_EQ(tok, "EXCEPT"))		/* EXCEPT: give up */
+	    return (NO);
+	if (match_fn(tok, request)) {		/* YES: look for exceptions */
+	    while ((tok = strtok((char *) 0, sep)) && STR_NE(tok, "EXCEPT"))
+		 /* VOID */ ;
+	    return (tok == 0 || list_match((char *) 0, request, match_fn) == 0);
+	}
+    }
+    return (NO);
+}
+
+/* server_match - match server information */
+
+static int server_match(tok, request)
+char   *tok;
+struct request_info *request;
+{
+    char   *host;
+
+    if ((host = split_at(tok + 1, '@')) == 0) {	/* plain daemon */
+	return (string_match(tok, eval_daemon(request)));
+    } else {					/* daemon@host */
+	return (string_match(tok, eval_daemon(request))
+		&& host_match(host, request->server));
+    }
+}
+
+/* client_match - match client information */
+
+static int client_match(tok, request)
+char   *tok;
+struct request_info *request;
+{
+    char   *host;
+
+    if ((host = split_at(tok + 1, '@')) == 0) {	/* plain host */
+	return (host_match(tok, request->client));
+    } else {					/* user@host */
+	return (host_match(host, request->client)
+		&& string_match(tok, eval_user(request)));
+    }
+}
+
+/* host_match - match host name and/or address against pattern */
+
+static int host_match(tok, host)
+char   *tok;
+struct host_info *host;
+{
+    char   *mask;
+
+    /*
+     * This code looks a little hairy because we want to avoid unnecessary
+     * hostname lookups.
+     * 
+     * The KNOWN pattern requires that both address AND name be known; some
+     * patterns are specific to host names or to host addresses; all other
+     * patterns are satisfied when either the address OR the name match.
+     */
+
+    if (tok[0] == '@') {			/* netgroup: look it up */
+#ifdef  NETGROUP
+	static char *mydomain = 0;
+	if (mydomain == 0)
+	    yp_get_default_domain(&mydomain);
+	return (innetgr(tok + 1, eval_hostname(host), (char *) 0, mydomain));
+#else
+	tcpd_warn("netgroup support is disabled");	/* not tcpd_jump() */
+	return (NO);
+#endif
+    } else if (STR_EQ(tok, "KNOWN")) {		/* check address and name */
+	char   *name = eval_hostname(host);
+	return (STR_NE(eval_hostaddr(host), unknown) && HOSTNAME_KNOWN(name));
+    } else if (STR_EQ(tok, "LOCAL")) {		/* local: no dots in name */
+	char   *name = eval_hostname(host);
+	return (strchr(name, '.') == 0 && HOSTNAME_KNOWN(name));
+    } else if ((mask = split_at(tok, '/')) != 0) {	/* net/mask */
+	return (masked_match(tok, mask, eval_hostaddr(host)));
+    } else {					/* anything else */
+	return (string_match(tok, eval_hostaddr(host))
+	    || (NOT_INADDR(tok) && string_match(tok, eval_hostname(host))));
+    }
+}
+
+/* string_match - match string against pattern */
+
+static int string_match(tok, string)
+char   *tok;
+char   *string;
+{
+    int     n;
+
+    if (tok[0] == '.') {			/* suffix */
+	n = strlen(string) - strlen(tok);
+	return (n > 0 && STR_EQ(tok, string + n));
+    } else if (STR_EQ(tok, "ALL")) {		/* all: match any */
+	return (YES);
+    } else if (STR_EQ(tok, "KNOWN")) {		/* not unknown */
+	return (STR_NE(string, unknown));
+    } else if (tok[(n = strlen(tok)) - 1] == '.') {	/* prefix */
+	return (STRN_EQ(tok, string, n));
+    } else {					/* exact match */
+	return (STR_EQ(tok, string));
+    }
+}
+
+/* masked_match - match address against netnumber/netmask */
+
+static int masked_match(net_tok, mask_tok, string)
+char   *net_tok;
+char   *mask_tok;
+char   *string;
+{
+    unsigned long net;
+    unsigned long mask;
+    unsigned long addr;
+
+    /*
+     * Disallow forms other than dotted quad: the treatment that inet_addr()
+     * gives to forms with less than four components is inconsistent with the
+     * access control language. John P. Rouillard <rouilj@cs.umb.edu>.
+     */
+
+    if ((addr = dot_quad_addr(string)) == INADDR_NONE)
+	return (NO);
+    if ((net = dot_quad_addr(net_tok)) == INADDR_NONE
+	|| (mask = dot_quad_addr(mask_tok)) == INADDR_NONE) {
+	tcpd_warn("bad net/mask expression: %s/%s", net_tok, mask_tok);
+	return (NO);				/* not tcpd_jump() */
+    }
+    return ((addr & mask) == net);
+}
diff --git a/lib/libwrap/hosts_ctl.c b/lib/libwrap/hosts_ctl.c
new file mode 100644
index 00000000000..ec53c3f2694
--- /dev/null
+++ b/lib/libwrap/hosts_ctl.c
@@ -0,0 +1,44 @@
+/*	$OpenBSD: hosts_ctl.c,v 1.1 1997/02/26 03:06:53 downsj Exp $	*/
+
+ /*
+  * hosts_ctl() combines common applications of the host access control
+  * library routines. It bundles its arguments then calls the hosts_access()
+  * access control checker. The host name and user name arguments should be
+  * empty strings, STRING_UNKNOWN or real data. If a match is found, the
+  * optional shell command is executed.
+  * 
+  * Restriction: this interface does not pass enough information to support
+  * selective remote username lookups or selective hostname double checks.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) hosts_ctl.c 1.4 94/12/28 17:42:27";
+#else
+static char rcsid[] = "$OpenBSD: hosts_ctl.c,v 1.1 1997/02/26 03:06:53 downsj Exp $";
+#endif
+#endif
+
+#include <stdio.h>
+
+#include "tcpd.h"
+
+/* hosts_ctl - limited interface to the hosts_access() routine */
+
+int     hosts_ctl(daemon, name, addr, user)
+char   *daemon;
+char   *name;
+char   *addr;
+char   *user;
+{
+    struct request_info request;
+
+    return (hosts_access(request_init(&request,
+				      RQ_DAEMON, daemon,
+				      RQ_CLIENT_NAME, name,
+				      RQ_CLIENT_ADDR, addr,
+				      RQ_USER, user,
+				      0)));
+}
diff --git a/lib/libwrap/hosts_options.5 b/lib/libwrap/hosts_options.5
new file mode 100644
index 00000000000..0a727c9e76e
--- /dev/null
+++ b/lib/libwrap/hosts_options.5
@@ -0,0 +1,173 @@
+.\"	$OpenBSD: hosts_options.5,v 1.1 1997/02/26 03:06:53 downsj Exp $
+.TH HOSTS_OPTIONS 5
+.SH NAME
+hosts_options \- host access control language extensions
+.SH DESCRIPTION
+This document describes optional extensions to the language described
+in the hosts_access(5) document. The extensions are enabled at program
+build time. For example, by editing the Makefile and turning on the 
+PROCESS_OPTIONS compile-time option.
+.PP
+The extensible language uses the following format:
+.sp
+.ti +3
+daemon_list : client_list : option : option ...
+.PP
+The first two fields are described in the hosts_access(5) manual page.
+The remainder of the rules is a list of zero or more options.  Any ":"
+characters within options should be protected with a backslash.
+.PP
+An option is of the form "keyword" or "keyword value". Options are
+processed in the specified order. Some options are subjected to
+%<letter> substitutions. For the sake of backwards compatibility with
+earlier versions, an "=" is permitted between keyword and value.
+.SH LOGGING
+.IP "severity mail.info"
+.IP "severity notice"
+Change the severity level at which the event will be logged. Facility
+names (such as mail) are optional, and are not supported on systems
+with older syslog implementations. The severity option can be used
+to emphasize or to ignore specific events.
+.SH ACCESS CONTROL
+.IP "allow"
+.IP "deny"
+Grant (deny) service. These options must appear at the end of a rule.
+.PP
+The \fIallow\fR and \fIdeny\fR keywords make it possible to keep all
+access control rules within a single file, for example in the
+\fIhosts.allow\fR file.
+.sp
+To permit access from specific hosts only:
+.sp
+.ne 2
+.ti +3
+ALL: .friendly.domain: ALLOW
+.ti +3
+ALL: ALL: DENY
+.sp
+To permit access from all hosts except a few trouble makers:
+.sp
+.ne 2
+.ti +3
+ALL: .bad.domain: DENY
+.ti +3
+ALL: ALL: ALLOW
+.sp
+Notice the leading dot on the domain name patterns.
+.SH RUNNING OTHER COMMANDS
+.IP "spawn shell_command"
+Execute, in a child process, the specified shell command, after
+performing the %<letter> expansions described in the hosts_access(5)
+manual page.  The command is executed with stdin, stdout and stderr
+connected to the null device, so that it won\'t mess up the
+conversation with the client host. Example:
+.sp
+.nf
+.ti +3
+spawn (/some/where/safe_finger -l @%h | /usr/ucb/mail root) &
+.fi
+.sp
+executes, in a background child process, the shell command "safe_finger
+-l @%h | mail root" after replacing %h by the name or address of the
+remote host.
+.sp
+The example uses the "safe_finger" command instead of the regular
+"finger" command, to limit possible damage from data sent by the finger
+server. The "safe_finger" command is part of the daemon wrapper
+package; it is a wrapper around the regular finger command that filters
+the data sent by the remote host.
+.IP "twist shell_command"
+Replace the current process by an instance of the specified shell
+command, after performing the %<letter> expansions described in the
+hosts_access(5) manual page.  Stdin, stdout and stderr are connected to
+the client process. This option must appear at the end of a rule.
+.sp
+To send a customized bounce message to the client instead of
+running the real ftp daemon:
+.sp
+.nf
+.ti +3
+in.ftpd : ... : twist /bin/echo 421 Some bounce message
+.fi
+.sp
+For an alternative way to talk to client processes, see the
+\fIbanners\fR option below.
+.sp
+To run /some/other/in.telnetd without polluting its command-line
+array or its process environment:
+.sp
+.nf
+.ti +3
+in.telnetd : ... : twist PATH=/some/other; exec in.telnetd
+.fi
+.sp
+Warning:  in case of UDP services, do not twist to commands that use
+the standard I/O or the read(2)/write(2) routines to communicate with
+the client process; UDP requires other I/O primitives.
+.SH NETWORK OPTIONS
+.IP "keepalive"
+Causes the server to periodically send a message to the client.  The
+connection is considered broken when the client does not respond. The
+keepalive option can be useful when users turn off their machine while
+it is still connected to a server.  The keepalive option is not useful
+for datagram (UDP) services.
+.IP "linger number_of_seconds"
+Specifies how long the kernel will try to deliver not-yet delivered
+data after the server process closes a connection. 
+.SH USERNAME LOOKUP
+.IP "rfc931 [ timeout_in_seconds ]"
+Look up the client user name with the RFC 931 (TAP, IDENT, RFC 1413)
+protocol.  This option is silently ignored in case of services based on
+transports other than TCP.  It requires that the client system runs an
+RFC 931 (IDENT, etc.) -compliant daemon, and may cause noticeable
+delays with connections from non-UNIX clients.  The timeout period is
+optional. If no timeout is specified a compile-time defined default
+value is taken.
+.SH MISCELLANEOUS
+.IP "banners /some/directory"
+Look for a file in `/some/directory' with the same name as the daemon
+process (for example in.telnetd for the telnet service), and copy its
+contents to the client. Newline characters are replaced by
+carriage-return newline, and %<letter> sequences are expanded (see
+the hosts_access(5) manual page).
+.sp
+The tcp wrappers source code distribution provides a sample makefile
+(Banners.Makefile) for convenient banner maintenance.
+.sp
+Warning: banners are supported for connection-oriented (TCP) network
+services only.
+.IP "nice [ number ]"
+Change the nice value of the process (default 10).  Specify a positive
+value to spend more CPU resources on other processes. 
+.IP "setenv name value"
+Place a (name, value) pair into the process environment. The value is
+subjected to %<letter> expansions and may contain whitespace (but
+leading and trailing blanks are stripped off).
+.sp
+Warning: many network daemons reset their environment before spawning a
+login or shell process.
+.IP "umask 022"
+Like the umask command that is built into the shell. An umask of 022
+prevents the creation of files with group and world write permission.
+The umask argument should be an octal number.
+.IP "user nobody"
+.IP "user nobody.kmem"
+Assume the privileges of the "nobody" userid (or user "nobody", group
+"kmem"). The first form is useful with inetd implementations that run
+all services with root privilege. The second form is useful for
+services that need special group privileges only.
+.SH DIAGNOSTICS
+When a syntax error is found in an access control rule, the error
+is reported to the syslog daemon; further options will be ignored,
+and service is denied.
+.SH SEE ALSO
+hosts_access(5), the default access control language
+.SH AUTHOR
+.na
+.nf
+Wietse Venema (wietse@wzv.win.tue.nl)
+Department of Mathematics and Computing Science
+Eindhoven University of Technology
+Den Dolech 2, P.O. Box 513, 
+5600 MB Eindhoven, The Netherlands
+\" @(#) hosts_options.5 1.10 94/12/28 17:42:28
diff --git a/lib/libwrap/misc.c b/lib/libwrap/misc.c
new file mode 100644
index 00000000000..7819fb59309
--- /dev/null
+++ b/lib/libwrap/misc.c
@@ -0,0 +1,91 @@
+/*	$OpenBSD: misc.c,v 1.1 1997/02/26 03:06:53 downsj Exp $	*/
+
+ /*
+  * Misc routines that are used by tcpd and by tcpdchk.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsic[] = "@(#) misc.c 1.2 96/02/11 17:01:29";
+#else
+static char rcsid[] = "$OpenBSD: misc.c,v 1.1 1997/02/26 03:06:53 downsj Exp $";
+#endif
+#endif
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "tcpd.h"
+
+#ifndef	INADDR_NONE
+#define	INADDR_NONE	(-1)		/* XXX should be 0xffffffff */
+#endif
+
+/* xgets - fgets() with backslash-newline stripping */
+
+char   *xgets(ptr, len, fp)
+char   *ptr;
+int     len;
+FILE   *fp;
+{
+    int     got;
+    char   *start = ptr;
+
+    while (fgets(ptr, len, fp)) {
+	got = strlen(ptr);
+	if (got >= 1 && ptr[got - 1] == '\n') {
+	    tcpd_context.line++;
+	    if (got >= 2 && ptr[got - 2] == '\\') {
+		got -= 2;
+	    } else {
+		return (start);
+	    }
+	}
+	ptr += got;
+	len -= got;
+	ptr[0] = 0;
+    }
+    return (ptr > start ? start : 0);
+}
+
+/* split_at - break string at delimiter or return NULL */
+
+char   *split_at(string, delimiter)
+char   *string;
+int     delimiter;
+{
+    char   *cp;
+
+    if ((cp = strchr(string, delimiter)) != 0)
+	*cp++ = 0;
+    return (cp);
+}
+
+/* dot_quad_addr - convert dotted quad to internal form */
+
+unsigned long dot_quad_addr(str)
+char   *str;
+{
+    int     in_run = 0;
+    int     runs = 0;
+    char   *cp = str;
+
+    /* Count the number of runs of non-dot characters. */
+
+    while (*cp) {
+	if (*cp == '.') {
+	    in_run = 0;
+	} else if (in_run == 0) {
+	    in_run = 1;
+	    runs++;
+	}
+	cp++;
+    }
+    return (runs == 4 ? inet_addr(str) : INADDR_NONE);
+}
diff --git a/lib/libwrap/options.c b/lib/libwrap/options.c
new file mode 100644
index 00000000000..30e456f3887
--- /dev/null
+++ b/lib/libwrap/options.c
@@ -0,0 +1,629 @@
+/*	$OpenBSD: options.c,v 1.1 1997/02/26 03:06:54 downsj Exp $	*/
+
+ /*
+  * General skeleton for adding options to the access control language. The
+  * features offered by this module are documented in the hosts_options(5)
+  * manual page (source file: hosts_options.5, "nroff -man" format).
+  * 
+  * Notes and warnings for those who want to add features:
+  * 
+  * In case of errors, abort options processing and deny access. There are too
+  * many irreversible side effects to make error recovery feasible. For
+  * example, it makes no sense to continue after we have already changed the
+  * userid.
+  * 
+  * In case of errors, do not terminate the process: the routines might be
+  * called from a long-running daemon that should run forever. Instead, call
+  * tcpd_jump() which does a non-local goto back into the hosts_access()
+  * routine.
+  * 
+  * In case of severe errors, use clean_exit() instead of directly calling
+  * exit(), or the inetd may loop on an UDP request.
+  * 
+  * In verification mode (for example, with the "tcpdmatch" command) the
+  * "dry_run" flag is set. In this mode, an option function should just "say"
+  * what it is going to do instead of really doing it.
+  * 
+  * Some option functions do not return (for example, the twist option passes
+  * control to another program). In verification mode (dry_run flag is set)
+  * such options should clear the "dry_run" flag to inform the caller of this
+  * course of action.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) options.c 1.17 96/02/11 17:01:31";
+#else
+static char rcsid[] = "$OpenBSD: options.c,v 1.1 1997/02/26 03:06:54 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <syslog.h>
+#include <pwd.h>
+#include <grp.h>
+#include <ctype.h>
+#include <setjmp.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifndef MAXPATHNAMELEN
+#define MAXPATHNAMELEN  BUFSIZ
+#endif
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+/* Options runtime support. */
+
+int     dry_run = 0;			/* flag set in verification mode */
+extern jmp_buf tcpd_buf;		/* tcpd_jump() support */
+
+/* Options parser support. */
+
+static char whitespace_eq[] = "= \t\r\n";
+#define whitespace (whitespace_eq + 1)
+
+static char *get_field();		/* chew :-delimited field off string */
+static char *chop_string();		/* strip leading and trailing blanks */
+
+/* List of functions that implement the options. Add yours here. */
+
+static void user_option();		/* execute "user name.group" option */
+static void group_option();		/* execute "group name" option */
+static void umask_option();		/* execute "umask mask" option */
+static void linger_option();		/* execute "linger time" option */
+static void keepalive_option();		/* execute "keepalive" option */
+static void spawn_option();		/* execute "spawn command" option */
+static void twist_option();		/* execute "twist command" option */
+static void rfc931_option();		/* execute "rfc931" option */
+static void setenv_option();		/* execute "setenv name value" */
+static void nice_option();		/* execute "nice" option */
+static void severity_option();		/* execute "severity value" */
+static void allow_option();		/* execute "allow" option */
+static void deny_option();		/* execute "deny" option */
+static void banners_option();		/* execute "banners path" option */
+
+/* Structure of the options table. */
+
+struct option {
+    char   *name;			/* keyword name, case is ignored */
+    void  (*func) ();			/* function that does the real work */
+    int     flags;			/* see below... */
+};
+
+#define NEED_ARG	(1<<1)		/* option requires argument */
+#define USE_LAST	(1<<2)		/* option must be last */
+#define OPT_ARG		(1<<3)		/* option has optional argument */
+#define EXPAND_ARG	(1<<4)		/* do %x expansion on argument */
+
+#define need_arg(o)	((o)->flags & NEED_ARG)
+#define opt_arg(o)	((o)->flags & OPT_ARG)
+#define permit_arg(o)	((o)->flags & (NEED_ARG | OPT_ARG))
+#define use_last(o)	((o)->flags & USE_LAST)
+#define expand_arg(o)	((o)->flags & EXPAND_ARG)
+
+/* List of known keywords. Add yours here. */
+
+static struct option option_table[] = {
+    "user", user_option, NEED_ARG,
+    "group", group_option, NEED_ARG,
+    "umask", umask_option, NEED_ARG,
+    "linger", linger_option, NEED_ARG,
+    "keepalive", keepalive_option, 0,
+    "spawn", spawn_option, NEED_ARG | EXPAND_ARG,
+    "twist", twist_option, NEED_ARG | EXPAND_ARG | USE_LAST,
+    "rfc931", rfc931_option, OPT_ARG,
+    "setenv", setenv_option, NEED_ARG | EXPAND_ARG,
+    "nice", nice_option, OPT_ARG,
+    "severity", severity_option, NEED_ARG,
+    "allow", allow_option, USE_LAST,
+    "deny", deny_option, USE_LAST,
+    "banners", banners_option, NEED_ARG,
+    0,
+};
+
+/* process_options - process access control options */
+
+void    process_options(options, request)
+char   *options;
+struct request_info *request;
+{
+    char   *key;
+    char   *value;
+    char   *curr_opt;
+    char   *next_opt;
+    struct option *op;
+    char    bf[BUFSIZ];
+
+    for (curr_opt = get_field(options); curr_opt; curr_opt = next_opt) {
+	next_opt = get_field((char *) 0);
+
+	/*
+	 * Separate the option into name and value parts. For backwards
+	 * compatibility we ignore exactly one '=' between name and value.
+	 */
+	curr_opt = chop_string(curr_opt);
+	if (*(value = curr_opt + strcspn(curr_opt, whitespace_eq))) {
+	    if (*value != '=') {
+		*value++ = 0;
+		value += strspn(value, whitespace);
+	    }
+	    if (*value == '=') {
+		*value++ = 0;
+		value += strspn(value, whitespace);
+	    }
+	}
+	if (*value == 0)
+	    value = 0;
+	key = curr_opt;
+
+	/*
+	 * Disallow missing option names (and empty option fields).
+	 */
+	if (*key == 0)
+	    tcpd_jump("missing option name");
+
+	/*
+	 * Lookup the option-specific info and do some common error checks.
+	 * Delegate option-specific processing to the specific functions.
+	 */
+
+	for (op = option_table; op->name && STR_NE(op->name, key); op++)
+	     /* VOID */ ;
+	if (op->name == 0)
+	    tcpd_jump("bad option name: \"%s\"", key);
+	if (!value && need_arg(op))
+	    tcpd_jump("option \"%s\" requires value", key);
+	if (value && !permit_arg(op))
+	    tcpd_jump("option \"%s\" requires no value", key);
+	if (next_opt && use_last(op))
+	    tcpd_jump("option \"%s\" must be at end", key);
+	if (value && expand_arg(op))
+	    value = chop_string(percent_x(bf, sizeof(bf), value, request));
+	if (hosts_access_verbose)
+	    syslog(LOG_DEBUG, "option:   %s %s", key, value ? value : "");
+	(*(op->func)) (value, request);
+    }
+}
+
+/* allow_option - grant access */
+
+/* ARGSUSED */
+
+static void allow_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    longjmp(tcpd_buf, AC_PERMIT);
+}
+
+/* deny_option - deny access */
+
+/* ARGSUSED */
+
+static void deny_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    longjmp(tcpd_buf, AC_DENY);
+}
+
+/* banners_option - expand %<char>, terminate each line with CRLF */
+
+static void banners_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    char    path[MAXPATHNAMELEN];
+    char    ibuf[BUFSIZ];
+    char    obuf[2 * BUFSIZ];
+    struct stat st;
+    int     ch;
+    FILE   *fp;
+
+    sprintf(path, "%s/%s", value, eval_daemon(request));
+    if ((fp = fopen(path, "r")) != 0) {
+	while ((ch = fgetc(fp)) == 0)
+	    write(request->fd, "", 1);
+	ungetc(ch, fp);
+	while (fgets(ibuf, sizeof(ibuf) - 1, fp)) {
+	    if (split_at(ibuf, '\n'))
+		strcat(ibuf, "\r\n");
+	    percent_x(obuf, sizeof(obuf), ibuf, request);
+	    write(request->fd, obuf, strlen(obuf));
+	}
+	fclose(fp);
+    } else if (stat(value, &st) < 0) {
+	tcpd_warn("%s: %m", value);
+    }
+}
+
+/* group_option - switch group id */
+
+/* ARGSUSED */
+
+static void group_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    struct group *grp;
+    struct group *getgrnam();
+
+    if ((grp = getgrnam(value)) == 0)
+	tcpd_jump("unknown group: \"%s\"", value);
+    endgrent();
+
+    if (dry_run == 0 && setgid(grp->gr_gid))
+	tcpd_jump("setgid(%s): %m", value);
+}
+
+/* user_option - switch user id */
+
+/* ARGSUSED */
+
+static void user_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    struct passwd *pwd;
+    struct passwd *getpwnam();
+    char   *group;
+
+    if ((group = split_at(value, '.')) != 0)
+	group_option(group, request);
+    if ((pwd = getpwnam(value)) == 0)
+	tcpd_jump("unknown user: \"%s\"", value);
+    endpwent();
+
+    if (dry_run == 0 && setuid(pwd->pw_uid))
+	tcpd_jump("setuid(%s): %m", value);
+}
+
+/* umask_option - set file creation mask */
+
+/* ARGSUSED */
+
+static void umask_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    unsigned mask;
+    char    junk;
+
+    if (sscanf(value, "%o%c", &mask, &junk) != 1 || (mask & 0777) != mask)
+	tcpd_jump("bad umask value: \"%s\"", value);
+    (void) umask(mask);
+}
+
+/* spawn_option - spawn a shell command and wait */
+
+/* ARGSUSED */
+
+static void spawn_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    if (dry_run == 0)
+	shell_cmd(value);
+}
+
+/* linger_option - set the socket linger time (Marc Boucher <marc@cam.org>) */
+
+/* ARGSUSED */
+
+static void linger_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    struct linger linger;
+    char    junk;
+
+    if (sscanf(value, "%d%c", &linger.l_linger, &junk) != 1
+	|| linger.l_linger < 0)
+	tcpd_jump("bad linger value: \"%s\"", value);
+    if (dry_run == 0) {
+	linger.l_onoff = (linger.l_linger != 0);
+	if (setsockopt(request->fd, SOL_SOCKET, SO_LINGER, (char *) &linger,
+		       sizeof(linger)) < 0)
+	    tcpd_warn("setsockopt SO_LINGER %d: %m", linger.l_linger);
+    }
+}
+
+/* keepalive_option - set the socket keepalive option */
+
+/* ARGSUSED */
+
+static void keepalive_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    static int on = 1;
+
+    if (dry_run == 0 && setsockopt(request->fd, SOL_SOCKET, SO_KEEPALIVE,
+				   (char *) &on, sizeof(on)) < 0)
+	tcpd_warn("setsockopt SO_KEEPALIVE: %m");
+}
+
+/* nice_option - set nice value */
+
+/* ARGSUSED */
+
+static void nice_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    int     niceval = 10;
+    char    junk;
+
+    if (value != 0 && sscanf(value, "%d%c", &niceval, &junk) != 1)
+	tcpd_jump("bad nice value: \"%s\"", value);
+    if (dry_run == 0 && nice(niceval) < 0)
+	tcpd_warn("nice(%d): %m", niceval);
+}
+
+/* twist_option - replace process by shell command */
+
+static void twist_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    char   *error;
+
+    if (dry_run != 0) {
+	dry_run = 0;
+    } else {
+	if (resident > 0)
+	    tcpd_jump("twist option in resident process");
+
+	syslog(deny_severity, "twist %s to %s", eval_client(request), value);
+
+	/* Before switching to the shell, set up stdin, stdout and stderr. */
+
+#define maybe_dup2(from, to) ((from == to) ? to : (close(to), dup(from)))
+
+	if (maybe_dup2(request->fd, 0) != 0 ||
+	    maybe_dup2(request->fd, 1) != 1 ||
+	    maybe_dup2(request->fd, 2) != 2) {
+	    error = "twist_option: dup: %m";
+	} else {
+	    if (request->fd > 2)
+		close(request->fd);
+	    (void) execl("/bin/sh", "sh", "-c", value, (char *) 0);
+	    error = "twist_option: /bin/sh: %m";
+	}
+
+	/* Something went wrong: we MUST terminate the process. */
+
+	tcpd_warn(error);
+	clean_exit(request);
+    }
+}
+
+/* rfc931_option - look up remote user name */
+
+static void rfc931_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    int     timeout;
+    char    junk;
+
+    if (value != 0) {
+	if (sscanf(value, "%d%c", &timeout, &junk) != 1 || timeout <= 0)
+	    tcpd_jump("bad rfc931 timeout: \"%s\"", value);
+	rfc931_timeout = timeout;
+    }
+    (void) eval_user(request);
+}
+
+/* setenv_option - set environment variable */
+
+/* ARGSUSED */
+
+static void setenv_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    char   *var_value;
+
+    if (*(var_value = value + strcspn(value, whitespace)))
+	*var_value++ = 0;
+    if (setenv(chop_string(value), chop_string(var_value), 1))
+	tcpd_jump("memory allocation failure");
+}
+
+ /*
+  * The severity option goes last because it comes with a huge amount of ugly
+  * #ifdefs and tables.
+  */
+
+struct syslog_names {
+    char   *name;
+    int     value;
+};
+
+static struct syslog_names log_fac[] = {
+#ifdef LOG_KERN
+    "kern", LOG_KERN,
+#endif
+#ifdef LOG_USER
+    "user", LOG_USER,
+#endif
+#ifdef LOG_MAIL
+    "mail", LOG_MAIL,
+#endif
+#ifdef LOG_DAEMON
+    "daemon", LOG_DAEMON,
+#endif
+#ifdef LOG_AUTH
+    "auth", LOG_AUTH,
+#endif
+#ifdef LOG_LPR
+    "lpr", LOG_LPR,
+#endif
+#ifdef LOG_NEWS
+    "news", LOG_NEWS,
+#endif
+#ifdef LOG_UUCP
+    "uucp", LOG_UUCP,
+#endif
+#ifdef LOG_CRON
+    "cron", LOG_CRON,
+#endif
+#ifdef LOG_LOCAL0
+    "local0", LOG_LOCAL0,
+#endif
+#ifdef LOG_LOCAL1
+    "local1", LOG_LOCAL1,
+#endif
+#ifdef LOG_LOCAL2
+    "local2", LOG_LOCAL2,
+#endif
+#ifdef LOG_LOCAL3
+    "local3", LOG_LOCAL3,
+#endif
+#ifdef LOG_LOCAL4
+    "local4", LOG_LOCAL4,
+#endif
+#ifdef LOG_LOCAL5
+    "local5", LOG_LOCAL5,
+#endif
+#ifdef LOG_LOCAL6
+    "local6", LOG_LOCAL6,
+#endif
+#ifdef LOG_LOCAL7
+    "local7", LOG_LOCAL7,
+#endif
+    0,
+};
+
+static struct syslog_names log_sev[] = {
+#ifdef LOG_EMERG
+    "emerg", LOG_EMERG,
+#endif
+#ifdef LOG_ALERT
+    "alert", LOG_ALERT,
+#endif
+#ifdef LOG_CRIT
+    "crit", LOG_CRIT,
+#endif
+#ifdef LOG_ERR
+    "err", LOG_ERR,
+#endif
+#ifdef LOG_WARNING
+    "warning", LOG_WARNING,
+#endif
+#ifdef LOG_NOTICE
+    "notice", LOG_NOTICE,
+#endif
+#ifdef LOG_INFO
+    "info", LOG_INFO,
+#endif
+#ifdef LOG_DEBUG
+    "debug", LOG_DEBUG,
+#endif
+    0,
+};
+
+/* severity_map - lookup facility or severity value */
+
+static int severity_map(table, name)
+struct syslog_names *table;
+char   *name;
+{
+    struct syslog_names *t;
+
+    for (t = table; t->name; t++)
+	if (STR_EQ(t->name, name))
+	    return (t->value);
+    tcpd_jump("bad syslog facility or severity: \"%s\"", name);
+    /* NOTREACHED */
+}
+
+/* severity_option - change logging severity for this event (Dave Mitchell) */
+
+/* ARGSUSED */
+
+static void severity_option(value, request)
+char   *value;
+struct request_info *request;
+{
+    char   *level = split_at(value, '.');
+
+    allow_severity = deny_severity = level ?
+	severity_map(log_fac, value) | severity_map(log_sev, level) :
+	severity_map(log_sev, value);
+}
+
+/* get_field - return pointer to next field in string */
+
+static char *get_field(string)
+char   *string;
+{
+    static char *last = "";
+    char   *src;
+    char   *dst;
+    char   *ret;
+    int     ch;
+
+    /*
+     * This function returns pointers to successive fields within a given
+     * string. ":" is the field separator; warn if the rule ends in one. It
+     * replaces a "\:" sequence by ":", without treating the result of
+     * substitution as field terminator. A null argument means resume search
+     * where the previous call terminated. This function destroys its
+     * argument.
+     * 
+     * Work from explicit source or from memory. While processing \: we
+     * overwrite the input. This way we do not have to maintain buffers for
+     * copies of input fields.
+     */
+
+    src = dst = ret = (string ? string : last);
+    if (src[0] == 0)
+	return (0);
+
+    while ((ch = *src)) {
+	if (ch == ':') {
+	    if (*++src == 0)
+		tcpd_warn("rule ends in \":\"");
+	    break;
+	}
+	if (ch == '\\' && src[1] == ':')
+	    src++;
+	*dst++ = *src++;
+    }
+    last = src;
+    *dst = 0;
+    return (ret);
+}
+
+/* chop_string - strip leading and trailing blanks from string */
+
+static char *chop_string(string)
+register char *string;
+{
+    char   *start = 0;
+    char   *end;
+    char   *cp;
+
+    for (cp = string; *cp; cp++) {
+	if (!isspace(*cp)) {
+	    if (start == 0)
+		start = cp;
+	    end = cp;
+	}
+    }
+    return (start ? (end[1] = 0, start) : cp);
+}
diff --git a/lib/libwrap/percent_m.c b/lib/libwrap/percent_m.c
new file mode 100644
index 00000000000..86f531619ea
--- /dev/null
+++ b/lib/libwrap/percent_m.c
@@ -0,0 +1,49 @@
+/*	$OpenBSD: percent_m.c,v 1.1 1997/02/26 03:06:54 downsj Exp $	*/
+
+ /*
+  * Replace %m by system error message.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) percent_m.c 1.1 94/12/28 17:42:37";
+#else
+static char rcsid[] = "$OpenBSD: percent_m.c,v 1.1 1997/02/26 03:06:54 downsj Exp $";
+#endif
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <errno.h>
+#include <string.h>
+
+extern int errno;
+#ifndef SYS_ERRLIST_DEFINED
+extern char *sys_errlist[];
+extern int sys_nerr;
+#endif
+
+char   *percent_m(obuf, ibuf)
+char   *obuf;
+char   *ibuf;
+{
+    char   *bp = obuf;
+    char   *cp = ibuf;
+
+    while ((*bp = *cp)) {
+	if (*cp == '%' && cp[1] == 'm') {
+	    if (errno < sys_nerr && errno > 0) {
+		strcpy(bp, sys_errlist[errno]);
+	    } else {
+		sprintf(bp, "Unknown error %d", errno);
+	    }
+	    bp += strlen(bp);
+	    cp += 2;
+	} else {
+	    bp++, cp++;
+	}
+    }
+    return (obuf);
+}
diff --git a/lib/libwrap/percent_x.c b/lib/libwrap/percent_x.c
new file mode 100644
index 00000000000..96eb5eb8ed9
--- /dev/null
+++ b/lib/libwrap/percent_x.c
@@ -0,0 +1,91 @@
+/*	$OpenBSD: percent_x.c,v 1.1 1997/02/26 03:06:55 downsj Exp $	*/
+
+ /*
+  * percent_x() takes a string and performs %<char> expansions. It aborts the
+  * program when the expansion would overflow the output buffer. The result
+  * of %<char> expansion may be passed on to a shell process. For this
+  * reason, characters with a special meaning to shells are replaced by
+  * underscores.
+  * 
+  * Diagnostics are reported through syslog(3).
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) percent_x.c 1.4 94/12/28 17:42:37";
+#else
+static char rcsid[] = "$OpenBSD: percent_x.c,v 1.1 1997/02/26 03:06:55 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <stdio.h>
+#include <syslog.h>
+#include <string.h>
+#include <unistd.h>
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+/* percent_x - do %<char> expansion, abort if result buffer is too small */
+
+char   *percent_x(result, result_len, string, request)
+char   *result;
+int     result_len;
+char   *string;
+struct request_info *request;
+{
+    char   *bp = result;
+    char   *end = result + result_len - 1;	/* end of result buffer */
+    char   *expansion;
+    int     expansion_len;
+    static char ok_chars[] = "1234567890!@%-_=+:,./\
+abcdefghijklmnopqrstuvwxyz\
+ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+    char   *str = string;
+    char   *cp;
+    int     ch;
+
+    /*
+     * Warning: we may be called from a child process or after pattern
+     * matching, so we cannot use clean_exit() or tcpd_jump().
+     */
+
+    while (*str) {
+	if (*str == '%' && (ch = str[1]) != 0) {
+	    str += 2;
+	    expansion =
+		ch == 'a' ? eval_hostaddr(request->client) :
+		ch == 'A' ? eval_hostaddr(request->server) :
+		ch == 'c' ? eval_client(request) :
+		ch == 'd' ? eval_daemon(request) :
+		ch == 'h' ? eval_hostinfo(request->client) :
+		ch == 'H' ? eval_hostinfo(request->server) :
+		ch == 'n' ? eval_hostname(request->client) :
+		ch == 'N' ? eval_hostname(request->server) :
+		ch == 'p' ? eval_pid(request) :
+		ch == 's' ? eval_server(request) :
+		ch == 'u' ? eval_user(request) :
+		ch == '%' ? "%" : (tcpd_warn("unrecognized %%%c", ch), "");
+	    for (cp = expansion; *(cp += strspn(cp, ok_chars)); /* */ )
+		*cp = '_';
+	    expansion_len = cp - expansion;
+	} else {
+	    expansion = str++;
+	    expansion_len = 1;
+	}
+	if (bp + expansion_len >= end) {
+	    tcpd_warn("percent_x: expansion too long: %.30s...", result);
+	    sleep(5);
+	    exit(0);
+	}
+	memcpy(bp, expansion, expansion_len);
+	bp += expansion_len;
+    }
+    *bp = 0;
+    return (result);
+}
diff --git a/lib/libwrap/refuse.c b/lib/libwrap/refuse.c
new file mode 100644
index 00000000000..4860986db5b
--- /dev/null
+++ b/lib/libwrap/refuse.c
@@ -0,0 +1,38 @@
+/*	$OpenBSD: refuse.c,v 1.1 1997/02/26 03:06:55 downsj Exp $	*/
+
+ /*
+  * refuse() reports a refused connection, and takes the consequences: in
+  * case of a datagram-oriented service, the unread datagram is taken from
+  * the input queue (or inetd would see the same datagram again and again);
+  * the program is terminated.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) refuse.c 1.5 94/12/28 17:42:39";
+#else
+static char rcsid[] = "$OpenBSD: refuse.c,v 1.1 1997/02/26 03:06:55 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <stdio.h>
+#include <syslog.h>
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+/* refuse - refuse request */
+
+void    refuse(request)
+struct request_info *request;
+{
+    syslog(deny_severity, "refused connect from %s", eval_client(request));
+    clean_exit(request);
+    /* NOTREACHED */
+}
+
diff --git a/lib/libwrap/rfc931.c b/lib/libwrap/rfc931.c
new file mode 100644
index 00000000000..4bb94294e6c
--- /dev/null
+++ b/lib/libwrap/rfc931.c
@@ -0,0 +1,173 @@
+/*	$OpenBSD: rfc931.c,v 1.1 1997/02/26 03:06:56 downsj Exp $	*/
+
+ /*
+  * rfc931() speaks a common subset of the RFC 931, AUTH, TAP, IDENT and RFC
+  * 1413 protocols. It queries an RFC 931 etc. compatible daemon on a remote
+  * host to look up the owner of a connection. The information should not be
+  * used for authentication purposes. This routine intercepts alarm signals.
+  * 
+  * Diagnostics are reported through syslog(3).
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) rfc931.c 1.10 95/01/02 16:11:34";
+#else
+static char rcsid[] = "$OpenBSD: rfc931.c,v 1.1 1997/02/26 03:06:56 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <stdio.h>
+#include <syslog.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <setjmp.h>
+#include <signal.h>
+#include <string.h>
+#include <unistd.h>
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+#define	RFC931_PORT	113		/* Semi-well-known port */
+#define	ANY_PORT	0		/* Any old port will do */
+
+int     rfc931_timeout = RFC931_TIMEOUT;/* Global so it can be changed */
+
+static jmp_buf timebuf;
+
+/* fsocket - open stdio stream on top of socket */
+
+static FILE *fsocket(domain, type, protocol)
+int     domain;
+int     type;
+int     protocol;
+{
+    int     s;
+    FILE   *fp;
+
+    if ((s = socket(domain, type, protocol)) < 0) {
+	tcpd_warn("socket: %m");
+	return (0);
+    } else {
+	if ((fp = fdopen(s, "r+")) == 0) {
+	    tcpd_warn("fdopen: %m");
+	    close(s);
+	}
+	return (fp);
+    }
+}
+
+/* timeout - handle timeouts */
+
+static void timeout(sig)
+int     sig;
+{
+    longjmp(timebuf, sig);
+}
+
+/* rfc931 - return remote user name, given socket structures */
+
+void    rfc931(rmt_sin, our_sin, dest)
+struct sockaddr_in *rmt_sin;
+struct sockaddr_in *our_sin;
+char   *dest;
+{
+    unsigned rmt_port;
+    unsigned our_port;
+    struct sockaddr_in rmt_query_sin;
+    struct sockaddr_in our_query_sin;
+    char    user[256];			/* XXX */
+    char    buffer[512];		/* XXX */
+    char   *cp;
+    char   *result = unknown;
+    FILE   *fp;
+
+    /*
+     * Use one unbuffered stdio stream for writing to and for reading from
+     * the RFC931 etc. server. This is done because of a bug in the SunOS
+     * 4.1.x stdio library. The bug may live in other stdio implementations,
+     * too. When we use a single, buffered, bidirectional stdio stream ("r+"
+     * or "w+" mode) we read our own output. Such behaviour would make sense
+     * with resources that support random-access operations, but not with
+     * sockets.
+     */
+
+    if ((fp = fsocket(AF_INET, SOCK_STREAM, 0)) != 0) {
+	setbuf(fp, (char *) 0);
+
+	/*
+	 * Set up a timer so we won't get stuck while waiting for the server.
+	 */
+
+	if (setjmp(timebuf) == 0) {
+	    signal(SIGALRM, timeout);
+	    alarm(rfc931_timeout);
+
+	    /*
+	     * Bind the local and remote ends of the query socket to the same
+	     * IP addresses as the connection under investigation. We go
+	     * through all this trouble because the local or remote system
+	     * might have more than one network address. The RFC931 etc.
+	     * client sends only port numbers; the server takes the IP
+	     * addresses from the query socket.
+	     */
+
+	    our_query_sin = *our_sin;
+	    our_query_sin.sin_port = htons(ANY_PORT);
+	    rmt_query_sin = *rmt_sin;
+	    rmt_query_sin.sin_port = htons(RFC931_PORT);
+
+	    if (bind(fileno(fp), (struct sockaddr *) & our_query_sin,
+		     sizeof(our_query_sin)) >= 0 &&
+		connect(fileno(fp), (struct sockaddr *) & rmt_query_sin,
+			sizeof(rmt_query_sin)) >= 0) {
+
+		/*
+		 * Send query to server. Neglect the risk that a 13-byte
+		 * write would have to be fragmented by the local system and
+		 * cause trouble with buggy System V stdio libraries.
+		 */
+
+		fprintf(fp, "%u,%u\r\n",
+			ntohs(rmt_sin->sin_port),
+			ntohs(our_sin->sin_port));
+		fflush(fp);
+
+		/*
+		 * Read response from server. Use fgets()/sscanf() so we can
+		 * work around System V stdio libraries that incorrectly
+		 * assume EOF when a read from a socket returns less than
+		 * requested.
+		 */
+
+		if (fgets(buffer, sizeof(buffer), fp) != 0
+		    && ferror(fp) == 0 && feof(fp) == 0
+		    && sscanf(buffer, "%u , %u : USERID :%*[^:]:%255s",
+			      &rmt_port, &our_port, user) == 3
+		    && ntohs(rmt_sin->sin_port) == rmt_port
+		    && ntohs(our_sin->sin_port) == our_port) {
+
+		    /*
+		     * Strip trailing carriage return. It is part of the
+		     * protocol, not part of the data.
+		     */
+
+		    cp = strchr(user, '\r');
+		    if (cp)
+			*cp = 0;
+		    result = user;
+		}
+	    }
+	    alarm(0);
+	}
+	fclose(fp);
+    }
+    STRN_CPY(dest, result, STRING_LENGTH);
+}
diff --git a/lib/libwrap/scaffold.c b/lib/libwrap/scaffold.c
new file mode 100644
index 00000000000..8fab86f24af
--- /dev/null
+++ b/lib/libwrap/scaffold.c
@@ -0,0 +1,219 @@
+/*	$OpenBSD: scaffold.c,v 1.1 1997/02/26 03:06:56 downsj Exp $	*/
+
+ /*
+  * Routines for testing only. Not really industrial strength.
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccs_id[] = "@(#) scaffold.c 1.5 95/01/03 09:13:48";
+#else
+static char rcsid[] = "$OpenBSD: scaffold.c,v 1.1 1997/02/26 03:06:56 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <syslog.h>
+#include <setjmp.h>
+#include <string.h>
+
+#ifndef INADDR_NONE
+#define	INADDR_NONE	(-1)		/* XXX should be 0xffffffff */
+#endif
+
+extern char *malloc();
+
+/* Application-specific. */
+
+#include "tcpd.h"
+#include "scaffold.h"
+
+ /*
+  * These are referenced by the options module and by rfc931.c.
+  */
+int     allow_severity = SEVERITY;
+int     deny_severity = LOG_WARNING;
+int     rfc931_timeout = RFC931_TIMEOUT;
+
+/* dup_hostent - create hostent in one memory block */
+
+static struct hostent *dup_hostent(hp)
+struct hostent *hp;
+{
+    struct hostent_block {
+	struct hostent host;
+	char   *addr_list[1];
+    };
+    struct hostent_block *hb;
+    int     count;
+    char   *data;
+    char   *addr;
+
+    for (count = 0; hp->h_addr_list[count] != 0; count++)
+	 /* void */ ;
+
+    if ((hb = (struct hostent_block *) malloc(sizeof(struct hostent_block)
+			 + (hp->h_length + sizeof(char *)) * count)) == 0) {
+	fprintf(stderr, "Sorry, out of memory\n");
+	exit(1);
+    }
+    memset((char *) &hb->host, 0, sizeof(hb->host));
+    hb->host.h_length = hp->h_length;
+    hb->host.h_addr_list = hb->addr_list;
+    hb->host.h_addr_list[count] = 0;
+    data = (char *) (hb->host.h_addr_list + count + 1);
+
+    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
+	hb->host.h_addr_list[count] = data + hp->h_length * count;
+	memcpy(hb->host.h_addr_list[count], addr, hp->h_length);
+    }
+    return (&hb->host);
+}
+
+/* find_inet_addr - find all addresses for this host, result to free() */
+
+struct hostent *find_inet_addr(host)
+char   *host;
+{
+    struct in_addr addr;
+    struct hostent *hp;
+    static struct hostent h;
+    static char *addr_list[2];
+
+    /*
+     * Host address: translate it to internal form.
+     */
+    if ((addr.s_addr = dot_quad_addr(host)) != INADDR_NONE) {
+	h.h_addr_list = addr_list;
+	h.h_addr_list[0] = (char *) &addr;
+	h.h_length = sizeof(addr);
+	return (dup_hostent(&h));
+    }
+
+    /*
+     * Map host name to a series of addresses. Watch out for non-internet
+     * forms or aliases. The NOT_INADDR() is here in case gethostbyname() has
+     * been "enhanced" to accept numeric addresses. Make a copy of the
+     * address list so that later gethostbyXXX() calls will not clobber it.
+     */
+    if (NOT_INADDR(host) == 0) {
+	tcpd_warn("%s: not an internet address", host);
+	return (0);
+    }
+    if ((hp = gethostbyname(host)) == 0) {
+	tcpd_warn("%s: host not found", host);
+	return (0);
+    }
+    if (hp->h_addrtype != AF_INET) {
+	tcpd_warn("%d: not an internet host", hp->h_addrtype);
+	return (0);
+    }
+    if (STR_NE(host, hp->h_name)) {
+	tcpd_warn("%s: hostname alias", host);
+	tcpd_warn("(official name: %s)", hp->h_name);
+    }
+    return (dup_hostent(hp));
+}
+
+/* check_dns - give each address thorough workout, return address count */
+
+int     check_dns(host)
+char   *host;
+{
+    struct request_info request;
+    struct sockaddr_in sin;
+    struct hostent *hp;
+    int     count;
+    char   *addr;
+
+    if ((hp = find_inet_addr(host)) == 0)
+	return (0);
+    request_init(&request, RQ_CLIENT_SIN, &sin, 0);
+    sock_methods(&request);
+    memset((char *) &sin, 0, sizeof(sin));
+    sin.sin_family = AF_INET;
+
+    for (count = 0; (addr = hp->h_addr_list[count]) != 0; count++) {
+	memcpy((char *) &sin.sin_addr, addr, sizeof(sin.sin_addr));
+
+	/*
+	 * Force host name and address conversions. Use the request structure
+	 * as a cache. Detect hostname lookup problems. Any name/name or
+	 * name/address conflicts will be reported while eval_hostname() does
+	 * its job.
+	 */
+	request_set(&request, RQ_CLIENT_ADDR, "", RQ_CLIENT_NAME, "", 0);
+	if (STR_EQ(eval_hostname(request.client), unknown))
+	    tcpd_warn("host address %s->name lookup failed",
+		      eval_hostaddr(request.client));
+    }
+    free((char *) hp);
+    return (count);
+}
+
+/* dummy function to intercept the real shell_cmd() */
+
+/* ARGSUSED */
+
+void    shell_cmd(command)
+char   *command;
+{
+    if (hosts_access_verbose)
+	printf("command: %s", command);
+}
+
+/* dummy function  to intercept the real clean_exit() */
+
+/* ARGSUSED */
+
+void    clean_exit(request)
+struct request_info *request;
+{
+    exit(0);
+}
+
+/* dummy function  to intercept the real rfc931() */
+
+/* ARGSUSED */
+
+void    rfc931(request)
+struct request_info *request;
+{
+    strcpy(request->user, unknown);
+}
+
+/* check_path - examine accessibility */
+
+int     check_path(path, st)
+char   *path;
+struct stat *st;
+{
+    struct stat stbuf;
+    char    buf[BUFSIZ];
+
+    if (stat(path, st) < 0)
+	return (-1);
+#ifdef notdef
+    if (st->st_uid != 0)
+	tcpd_warn("%s: not owned by root", path);
+    if (st->st_mode & 020)
+	tcpd_warn("%s: group writable", path);
+#endif
+    if (st->st_mode & 002)
+	tcpd_warn("%s: world writable", path);
+    if (path[0] == '/' && path[1] != 0) {
+	strrchr(strcpy(buf, path), '/')[0] = 0;
+	(void) check_path(buf[0] ? buf : "/", &stbuf);
+    }
+    return (0);
+}
diff --git a/lib/libwrap/scaffold.h b/lib/libwrap/scaffold.h
new file mode 100644
index 00000000000..e89a9aa7aa2
--- /dev/null
+++ b/lib/libwrap/scaffold.h
@@ -0,0 +1,15 @@
+/*	$OpenBSD: scaffold.h,v 1.1 1997/02/26 03:06:57 downsj Exp $	*/
+
+ /*
+  * @(#) scaffold.h 1.3 94/12/31 18:19:19
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+extern struct hostent *find_inet_addr __P((char *));
+extern int check_dns __P((char *));
+extern int check_path __P((char *, struct stat *));
+__END_DECLS
diff --git a/lib/libwrap/shell_cmd.c b/lib/libwrap/shell_cmd.c
new file mode 100644
index 00000000000..b371f353616
--- /dev/null
+++ b/lib/libwrap/shell_cmd.c
@@ -0,0 +1,99 @@
+/*	$OpenBSD: shell_cmd.c,v 1.1 1997/02/26 03:06:57 downsj Exp $	*/
+
+ /*
+  * shell_cmd() takes a shell command after %<character> substitutions. The
+  * command is executed by a /bin/sh child process, with standard input,
+  * standard output and standard error connected to /dev/null.
+  * 
+  * Diagnostics are reported through syslog(3).
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) shell_cmd.c 1.5 94/12/28 17:42:44";
+#else
+static char rcsid[] = "$OpenBSD: shell_cmd.c,v 1.1 1997/02/26 03:06:57 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/wait.h>
+#include <signal.h>
+#include <stdio.h>
+#include <syslog.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+/* Forward declarations. */
+
+static void do_child();
+
+/* shell_cmd - execute shell command */
+
+void    shell_cmd(command)
+char   *command;
+{
+    int     child_pid;
+    int     wait_pid;
+
+    /*
+     * Most of the work is done within the child process, to minimize the
+     * risk of damage to the parent.
+     */
+
+    switch (child_pid = fork()) {
+    case -1:					/* error */
+	tcpd_warn("cannot fork: %m");
+	break;
+    case 00:					/* child */
+	do_child(command);
+	/* NOTREACHED */
+    default:					/* parent */
+	while ((wait_pid = wait((int *) 0)) != -1 && wait_pid != child_pid)
+	     /* void */ ;
+    }
+}
+
+/* do_child - exec command with { stdin, stdout, stderr } to /dev/null */
+
+static void do_child(command)
+char   *command;
+{
+    char   *error;
+    int     tmp_fd;
+
+    /*
+     * Systems with POSIX sessions may send a SIGHUP to grandchildren if the
+     * child exits first. This is sick, sessions were invented for terminals.
+     */
+
+    signal(SIGHUP, SIG_IGN);
+
+    /* Set up new stdin, stdout, stderr, and exec the shell command. */
+
+    for (tmp_fd = 0; tmp_fd < 3; tmp_fd++)
+	(void) close(tmp_fd);
+    if (open("/dev/null", O_RDWR) != 0) {
+	error = "open /dev/null: %m";
+    } else if (dup(0) != 1 || dup(0) != 2) {
+	error = "dup: %m";
+    } else {
+	(void) execl("/bin/sh", "sh", "-c", command, (char *) 0);
+	error = "execl /bin/sh: %m";
+    }
+
+    /* Something went wrong. We MUST terminate the child process. */
+
+    tcpd_warn(error);
+    _exit(0);
+}
diff --git a/lib/libwrap/shlib_version b/lib/libwrap/shlib_version
new file mode 100644
index 00000000000..1edea46de91
--- /dev/null
+++ b/lib/libwrap/shlib_version
@@ -0,0 +1,2 @@
+major=1
+minor=0
diff --git a/lib/libwrap/socket.c b/lib/libwrap/socket.c
new file mode 100644
index 00000000000..f1c9795a8b4
--- /dev/null
+++ b/lib/libwrap/socket.c
@@ -0,0 +1,240 @@
+/*	$OpenBSD: socket.c,v 1.1 1997/02/26 03:06:58 downsj Exp $	*/
+
+ /*
+  * This module determines the type of socket (datagram, stream), the client
+  * socket address and port, the server socket address and port. In addition,
+  * it provides methods to map a transport address to a printable host name
+  * or address. Socket address information results are in static memory.
+  * 
+  * The result from the hostname lookup method is STRING_PARANOID when a host
+  * pretends to have someone elses name, or when a host name is available but
+  * could not be verified.
+  * 
+  * When lookup or conversion fails the result is set to STRING_UNKNOWN.
+  * 
+  * Diagnostics are reported through syslog(3).
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) socket.c 1.14 95/01/30 19:51:50";
+#else
+static char rcsid[] = "$OpenBSD: socket.c,v 1.1 1997/02/26 03:06:58 downsj Exp $";
+#endif
+#endif
+
+/* System libraries. */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <syslog.h>
+#include <string.h>
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+/* Forward declarations. */
+
+static void sock_sink();
+
+#ifdef APPEND_DOT
+
+ /*
+  * Speed up DNS lookups by terminating the host name with a dot. Should be
+  * done with care. The speedup can give problems with lookups from sources
+  * that lack DNS-style trailing dot magic, such as local files or NIS maps.
+  */
+
+static struct hostent *gethostbyname_dot(name)
+char   *name;
+{
+    char    dot_name[MAXHOSTNAMELEN + 1];
+
+    /*
+     * Don't append dots to unqualified names. Such names are likely to come
+     * from local hosts files or from NIS.
+     */
+
+    if (strchr(name, '.') == 0 || strlen(name) >= MAXHOSTNAMELEN - 1) {
+	return (gethostbyname(name));
+    } else {
+	sprintf(dot_name, "%s.", name);
+	return (gethostbyname(dot_name));
+    }
+}
+
+#define gethostbyname gethostbyname_dot
+#endif
+
+/* sock_host - look up endpoint addresses and install conversion methods */
+
+void    sock_host(request)
+struct request_info *request;
+{
+    static struct sockaddr_in client;
+    static struct sockaddr_in server;
+    int     len;
+    char    buf[BUFSIZ];
+    int     fd = request->fd;
+
+    sock_methods(request);
+
+    /*
+     * Look up the client host address. Hal R. Brand <BRAND@addvax.llnl.gov>
+     * suggested how to get the client host info in case of UDP connections:
+     * peek at the first message without actually looking at its contents. We
+     * really should verify that client.sin_family gets the value AF_INET,
+     * but this program has already caused too much grief on systems with
+     * broken library code.
+     */
+
+    len = sizeof(client);
+    if (getpeername(fd, (struct sockaddr *) & client, &len) < 0) {
+	request->sink = sock_sink;
+	len = sizeof(client);
+	if (recvfrom(fd, buf, sizeof(buf), MSG_PEEK,
+		     (struct sockaddr *) & client, &len) < 0) {
+	    tcpd_warn("can't get client address: %m");
+	    return;				/* give up */
+	}
+#ifdef really_paranoid
+	memset(buf, 0 sizeof(buf));
+#endif
+    }
+    request->client->sin = &client;
+
+    /*
+     * Determine the server binding. This is used for client username
+     * lookups, and for access control rules that trigger on the server
+     * address or name.
+     */
+
+    len = sizeof(server);
+    if (getsockname(fd, (struct sockaddr *) & server, &len) < 0) {
+	tcpd_warn("getsockname: %m");
+	return;
+    }
+    request->server->sin = &server;
+}
+
+/* sock_hostaddr - map endpoint address to printable form */
+
+void    sock_hostaddr(host)
+struct host_info *host;
+{
+    struct sockaddr_in *sin = host->sin;
+
+    if (sin != 0)
+	STRN_CPY(host->addr, inet_ntoa(sin->sin_addr), sizeof(host->addr));
+}
+
+/* sock_hostname - map endpoint address to host name */
+
+void    sock_hostname(host)
+struct host_info *host;
+{
+    struct sockaddr_in *sin = host->sin;
+    struct hostent *hp;
+    int     i;
+
+    /*
+     * On some systems, for example Solaris 2.3, gethostbyaddr(0.0.0.0) does
+     * not fail. Instead it returns "INADDR_ANY". Unfortunately, this does
+     * not work the other way around: gethostbyname("INADDR_ANY") fails. We
+     * have to special-case 0.0.0.0, in order to avoid false alerts from the
+     * host name/address checking code below.
+     */
+    if (sin != 0 && sin->sin_addr.s_addr != 0
+	&& (hp = gethostbyaddr((char *) &(sin->sin_addr),
+			       sizeof(sin->sin_addr), AF_INET)) != 0) {
+
+	STRN_CPY(host->name, hp->h_name, sizeof(host->name));
+
+	/*
+	 * Verify that the address is a member of the address list returned
+	 * by gethostbyname(hostname).
+	 * 
+	 * Verify also that gethostbyaddr() and gethostbyname() return the same
+	 * hostname, or rshd and rlogind may still end up being spoofed.
+	 * 
+	 * On some sites, gethostbyname("localhost") returns "localhost.domain".
+	 * This is a DNS artefact. We treat it as a special case. When we
+	 * can't believe the address list from gethostbyname("localhost")
+	 * we're in big trouble anyway.
+	 */
+
+	if ((hp = gethostbyname(host->name)) == 0) {
+
+	    /*
+	     * Unable to verify that the host name matches the address. This
+	     * may be a transient problem or a botched name server setup.
+	     */
+
+	    tcpd_warn("can't verify hostname: gethostbyname(%s) failed",
+		      host->name);
+
+	} else if (STR_NE(host->name, hp->h_name)
+		   && STR_NE(host->name, "localhost")) {
+
+	    /*
+	     * The gethostbyaddr() and gethostbyname() calls did not return
+	     * the same hostname. This could be a nameserver configuration
+	     * problem. It could also be that someone is trying to spoof us.
+	     */
+
+	    tcpd_warn("host name/name mismatch: %s != %s",
+		      host->name, hp->h_name);
+
+	} else {
+
+	    /*
+	     * The address should be a member of the address list returned by
+	     * gethostbyname(). We should first verify that the h_addrtype
+	     * field is AF_INET, but this program has already caused too much
+	     * grief on systems with broken library code.
+	     */
+
+	    for (i = 0; hp->h_addr_list[i]; i++) {
+		if (memcmp(hp->h_addr_list[i],
+			   (char *) &sin->sin_addr,
+			   sizeof(sin->sin_addr)) == 0)
+		    return;			/* name is good, keep it */
+	    }
+
+	    /*
+	     * The host name does not map to the initial address. Perhaps
+	     * someone has messed up. Perhaps someone compromised a name
+	     * server.
+	     */
+
+	    tcpd_warn("host name/address mismatch: %s != %s",
+		      inet_ntoa(sin->sin_addr), hp->h_name);
+	}
+	strcpy(host->name, paranoid);		/* name is bad, clobber it */
+    }
+}
+
+/* sock_sink - absorb unreceived IP datagram */
+
+static void sock_sink(fd)
+int     fd;
+{
+    char    buf[BUFSIZ];
+    struct sockaddr_in sin;
+    int     size = sizeof(sin);
+
+    /*
+     * Eat up the not-yet received datagram. Some systems insist on a
+     * non-zero source address argument in the recvfrom() call below.
+     */
+
+    (void) recvfrom(fd, buf, sizeof(buf), 0, (struct sockaddr *) & sin, &size);
+}
diff --git a/lib/libwrap/tcpd.h b/lib/libwrap/tcpd.h
new file mode 100644
index 00000000000..aa6bd16d7f3
--- /dev/null
+++ b/lib/libwrap/tcpd.h
@@ -0,0 +1,221 @@
+/*	$OpenBSD: tcpd.h,v 1.1 1997/02/26 03:06:58 downsj Exp $	*/
+
+/*
+ * Copyright (c) 1997, Jason Downs.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
+ * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+ /*
+  * @(#) tcpd.h 1.5 96/03/19 16:22:24
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef _TCPD_H_
+#define _TCPD_H_
+
+#include <sys/cdefs.h>
+
+/* Structure to describe one communications endpoint. */
+
+#define STRING_LENGTH	128		/* hosts, users, processes */
+
+struct host_info {
+    char    name[STRING_LENGTH];	/* access via eval_hostname(host) */
+    char    addr[STRING_LENGTH];	/* access via eval_hostaddr(host) */
+    struct sockaddr_in *sin;		/* socket address or 0 */
+    struct t_unitdata *unit;		/* TLI transport address or 0 */
+    struct request_info *request;	/* for shared information */
+};
+
+/* Structure to describe what we know about a service request. */
+
+struct request_info {
+    int     fd;				/* socket handle */
+    char    user[STRING_LENGTH];	/* access via eval_user(request) */
+    char    daemon[STRING_LENGTH];	/* access via eval_daemon(request) */
+    char    pid[10];			/* access via eval_pid(request) */
+    struct host_info client[1];		/* client endpoint info */
+    struct host_info server[1];		/* server endpoint info */
+    void  (*sink) ();			/* datagram sink function or 0 */
+    void  (*hostname) ();		/* address to printable hostname */
+    void  (*hostaddr) ();		/* address to printable address */
+    void  (*cleanup) ();		/* cleanup function or 0 */
+    struct netconfig *config;		/* netdir handle */
+};
+
+/* Common string operations. Less clutter should be more readable. */
+
+#define STRN_CPY(d,s,l)	{ strncpy((d),(s),(l)); (d)[(l)-1] = 0; }
+
+#define STRN_EQ(x,y,l)	(strncasecmp((x),(y),(l)) == 0)
+#define STRN_NE(x,y,l)	(strncasecmp((x),(y),(l)) != 0)
+#define STR_EQ(x,y)	(strcasecmp((x),(y)) == 0)
+#define STR_NE(x,y)	(strcasecmp((x),(y)) != 0)
+
+ /*
+  * Initially, all above strings have the empty value. Information that
+  * cannot be determined at runtime is set to "unknown", so that we can
+  * distinguish between `unavailable' and `not yet looked up'. A hostname
+  * that we do not believe in is set to "paranoid".
+  */
+
+#define STRING_UNKNOWN	"unknown"	/* lookup failed */
+#define STRING_PARANOID	"paranoid"	/* hostname conflict */
+
+__BEGIN_DECLS
+extern char unknown[];
+extern char paranoid[];
+__END_DECLS
+
+#define HOSTNAME_KNOWN(s) (STR_NE((s),unknown) && STR_NE((s),paranoid))
+
+#define NOT_INADDR(s) (s[strspn(s,"01234567890./")] != 0)
+
+/* Global functions. */
+
+#define fromhost sock_host		/* no TLI support needed */
+
+__BEGIN_DECLS
+extern int hosts_access __P((struct request_info *));
+extern void shell_cmd __P((char *));
+extern char *percent_m __P((char *, char *));
+extern char *percent_x __P((char *, int, char *, struct request_info *));
+extern void rfc931 __P((struct sockaddr_in *, struct sockaddr_in *, char *));
+extern void clean_exit __P((struct request_info *));
+extern void refuse __P((struct request_info *));
+extern char *xgets __P((char *, int, FILE *));
+extern char *split_at __P((char *, int));
+extern unsigned long dot_quad_addr __P((char *));
+
+/* Global variables. */
+
+extern int allow_severity;		/* for connection logging */
+extern int deny_severity;		/* for connection logging */
+extern char *hosts_allow_table;		/* for verification mode redirection */
+extern char *hosts_deny_table;		/* for verification mode redirection */
+extern int hosts_access_verbose;	/* for verbose matching mode */
+extern int rfc931_timeout;		/* user lookup timeout */
+extern int resident;			/* > 0 if resident process */
+
+ /*
+  * Routines for controlled initialization and update of request structure
+  * attributes. Each attribute has its own key.
+  */
+
+extern struct request_info *request_init __P((struct request_info *, ...));
+extern struct request_info *request_set __P((struct request_info *, ...));
+
+#define RQ_FILE		1		/* file descriptor */
+#define RQ_DAEMON	2		/* server process (argv[0]) */
+#define RQ_USER		3		/* client user name */
+#define RQ_CLIENT_NAME	4		/* client host name */
+#define RQ_CLIENT_ADDR	5		/* client host address */
+#define RQ_CLIENT_SIN	6		/* client endpoint (internal) */
+#define RQ_SERVER_NAME	7		/* server host name */
+#define RQ_SERVER_ADDR	8		/* server host address */
+#define RQ_SERVER_SIN	9		/* server endpoint (internal) */
+
+ /*
+  * Routines for delayed evaluation of request attributes. Each attribute
+  * type has its own access method. The trivial ones are implemented by
+  * macros. The other ones are wrappers around the transport-specific host
+  * name, address, and client user lookup methods. The request_info and
+  * host_info structures serve as caches for the lookup results.
+  */
+
+extern char *eval_user __P((struct request_info *));
+extern char *eval_hostname __P((struct host_info *));
+extern char *eval_hostaddr __P((struct host_info *));
+extern char *eval_hostinfo __P((struct host_info *));
+extern char *eval_client __P((struct request_info *));
+extern char *eval_server __P((struct request_info *));
+#define eval_daemon(r)	((r)->daemon)	/* daemon process name */
+#define eval_pid(r)	((r)->pid)	/* process id */
+
+/* Socket-specific methods, including DNS hostname lookups. */
+
+extern void sock_host __P((struct request_info *));
+extern void sock_hostname __P((struct host_info *));
+extern void sock_hostaddr __P((struct host_info *));
+#define sock_methods(r) \
+	{ (r)->hostname = sock_hostname; (r)->hostaddr = sock_hostaddr; }
+
+ /*
+  * Problem reporting interface. Additional file/line context is reported
+  * when available. The jump buffer (tcpd_buf) is not declared here, or
+  * everyone would have to include <setjmp.h>.
+  */
+
+extern void tcpd_warn __P((char *, ...));
+extern void tcpd_jump __P((char *, ...));
+__END_DECLS
+
+struct tcpd_context {
+    char   *file;			/* current file */
+    int     line;			/* current line */
+};
+
+__BEGIN_DECLS
+extern struct tcpd_context tcpd_context;
+
+ /*
+  * While processing access control rules, error conditions are handled by
+  * jumping back into the hosts_access() routine. This is cleaner than
+  * checking the return value of each and every silly little function. The
+  * (-1) returns are here because zero is already taken by longjmp().
+  */
+
+#define AC_PERMIT	1		/* permit access */
+#define AC_DENY		(-1)		/* deny_access */
+#define AC_ERROR	AC_DENY		/* XXX */
+
+ /*
+  * In verification mode an option function should just say what it would do,
+  * instead of really doing it. An option function that would not return
+  * should clear the dry_run flag to inform the caller of this unusual
+  * behavior.
+  */
+
+extern void process_options __P((char *, struct request_info *));
+extern int dry_run;			/* verification flag */
+__END_DECLS
+
+
+ /*
+  * What follows is an attempt to unify varargs.h and stdarg.h. I'd rather
+  * have this than #ifdefs all over the code.
+  *
+  * The code using these must include the proper system header.
+  */
+
+#ifdef __STDC__
+#define VARARGS(func,type,arg) func(type arg, ...)
+#define VASTART(ap,type,name)  va_start(ap,name)
+#define VAEND(ap)              va_end(ap)
+#else
+#define VARARGS(func,type,arg) func(va_alist) va_dcl
+#define VASTART(ap,type,name)  {type name; va_start(ap); name = va_arg(ap, type)
+#define VAEND(ap)              va_end(ap);}
+#endif
+
+#endif	/* _TCPD_H_ */
diff --git a/lib/libwrap/update.c b/lib/libwrap/update.c
new file mode 100644
index 00000000000..d8eca07d3e0
--- /dev/null
+++ b/lib/libwrap/update.c
@@ -0,0 +1,126 @@
+/*	$OpenBSD: update.c,v 1.1 1997/02/26 03:06:59 downsj Exp $	*/
+
+ /*
+  * Routines for controlled update/initialization of request structures.
+  * 
+  * request_init() initializes its argument. Pointers and string-valued members
+  * are initialized to zero, to indicate that no lookup has been attempted.
+  * 
+  * request_set() adds information to an already initialized request structure.
+  * 
+  * Both functions take a variable-length name-value list.
+  * 
+  * Diagnostics are reported through syslog(3).
+  * 
+  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
+  */
+
+#ifndef lint
+#if 0
+static char sccsid[] = "@(#) update.c 1.1 94/12/28 17:42:56";
+#else
+static char rcsid[] = "$OpenBSD: update.c,v 1.1 1997/02/26 03:06:59 downsj Exp $";
+#endif
+#endif
+
+/* System libraries */
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <syslog.h>
+#include <string.h>
+#include <unistd.h>
+
+/* Local stuff. */
+
+#include "tcpd.h"
+
+/* request_fill - request update engine */
+
+static struct request_info *request_fill(request, ap)
+struct request_info *request;
+va_list ap;
+{
+    int     key;
+    char   *ptr;
+
+    while ((key = va_arg(ap, int)) > 0) {
+	switch (key) {
+	default:
+	    tcpd_warn("request_fill: invalid key: %d", key);
+	    return (request);
+	case RQ_FILE:
+	    request->fd = va_arg(ap, int);
+	    continue;
+	case RQ_CLIENT_SIN:
+	    request->client->sin = va_arg(ap, struct sockaddr_in *);
+	    continue;
+	case RQ_SERVER_SIN:
+	    request->server->sin = va_arg(ap, struct sockaddr_in *);
+	    continue;
+
+	    /*
+	     * All other fields are strings with the same maximal length.
+	     */
+
+	case RQ_DAEMON:
+	    ptr = request->daemon;
+	    break;
+	case RQ_USER:
+	    ptr = request->user;
+	    break;
+	case RQ_CLIENT_NAME:
+	    ptr = request->client->name;
+	    break;
+	case RQ_CLIENT_ADDR:
+	    ptr = request->client->addr;
+	    break;
+	case RQ_SERVER_NAME:
+	    ptr = request->server->name;
+	    break;
+	case RQ_SERVER_ADDR:
+	    ptr = request->server->addr;
+	    break;
+	}
+	STRN_CPY(ptr, va_arg(ap, char *), STRING_LENGTH);
+    }
+    return (request);
+}
+
+/* request_init - initialize request structure */
+
+struct request_info *VARARGS(request_init, struct request_info *, request)
+{
+    static struct request_info default_info;
+    struct request_info *r;
+    va_list ap;
+
+    /*
+     * Initialize data members. We do not assign default function pointer
+     * members, to avoid pulling in the whole socket module when it is not
+     * really needed.
+     */
+    VASTART(ap, struct request_info *, request);
+    *request = default_info;
+    request->fd = -1;
+    strcpy(request->daemon, unknown);
+    sprintf(request->pid, "%d", getpid());
+    request->client->request = request;
+    request->server->request = request;
+    r = request_fill(request, ap);
+    VAEND(ap);
+    return (r);
+}
+
+/* request_set - update request structure */
+
+struct request_info *VARARGS(request_set, struct request_info *, request)
+{
+    struct request_info *r;
+    va_list ap;
+
+    VASTART(ap, struct request_info *, request);
+    r = request_fill(request, ap);
+    VAEND(ap);
+    return (r);
+}