--- ./configure.ac.orig 2018-08-23 00:41:42.000000000 -0500 +++ ./configure.ac 2018-08-25 19:14:10.706002529 -0500 @@ -1502,6 +1502,62 @@ AC_MSG_RESULT([no]) fi +# Check whether user wants TCP wrappers support +TCPW_MSG="no" +AC_ARG_WITH([tcp-wrappers], + [ --with-tcp-wrappers[[=PATH]] Enable tcpwrappers support (optionally in PATH)], + [ + if test "x$withval" != "xno" ; then + saved_LIBS="$LIBS" + saved_LDFLAGS="$LDFLAGS" + saved_CPPFLAGS="$CPPFLAGS" + if test -n "${withval}" && \ + test "x${withval}" != "xyes"; then + if test -d "${withval}/lib"; then + if test -n "${need_dash_r}"; then + LDFLAGS="-L${withval}/lib -R${withval}/lib ${LDFLAGS}" + else + LDFLAGS="-L${withval}/lib ${LDFLAGS}" + fi + else + if test -n "${need_dash_r}"; then + LDFLAGS="-L${withval} -R${withval} ${LDFLAGS}" + else + LDFLAGS="-L${withval} ${LDFLAGS}" + fi + fi + if test -d "${withval}/include"; then + CPPFLAGS="-I${withval}/include ${CPPFLAGS}" + else + CPPFLAGS="-I${withval} ${CPPFLAGS}" + fi + fi + LIBS="-lwrap -lnsl $LIBS" + AC_MSG_CHECKING([for libwrap]) + AC_LINK_IFELSE([AC_LANG_PROGRAM([[ +#include +#include +#include +#include +int deny_severity = 0, allow_severity = 0; + ]], [[ + hosts_access(0); + ]])], [ + AC_MSG_RESULT([yes]) + AC_DEFINE([LIBWRAP], [1], + [Define if you want + TCP Wrappers support]) + SSHDLIBS="$SSHDLIBS -lwrap -lnsl" + TCPW_MSG="yes" + ], [ + AC_MSG_ERROR([*** libwrap missing]) + + ]) + LIBS="$saved_LIBS" + fi + ] +) + # Check whether user wants to use ldns LDNS_MSG="no" AC_ARG_WITH(ldns, @@ -5177,6 +5233,7 @@ echo " OSF SIA support: $SIA_MSG" echo " KerberosV support: $KRB5_MSG" echo " SELinux support: $SELINUX_MSG" +echo " TCP Wrappers support: $TCPW_MSG" echo " MD5 password support: $MD5_MSG" echo " libedit support: $LIBEDIT_MSG" echo " libldns support: $LDNS_MSG" --- ./sshd.c.orig 2018-08-23 00:41:42.000000000 -0500 +++ ./sshd.c 2018-08-25 19:12:52.901002527 -0500 @@ -122,6 +122,12 @@ #include "auth-options.h" #include "version.h" #include "ssherr.h" +#ifdef LIBWRAP +#include +#include +int allow_severity; +int deny_severity; +#endif /* LIBWRAP */ /* Re-exec fds */ #define REEXEC_DEVCRYPTO_RESERVED_FD (STDERR_FILENO + 1) @@ -2063,6 +2069,26 @@ packet_set_server(); ssh = active_state; /* XXX */ +/* Moved LIBWRAP check here */ +#ifdef LIBWRAP + allow_severity = options.log_facility|LOG_INFO; + deny_severity = options.log_facility|LOG_WARNING; + /* Check whether logins are denied from this host. */ + if (packet_connection_is_on_socket()) { /* This check must be after packet_set_connection() */ + struct request_info req; + + request_init(&req, RQ_DAEMON, __progname, RQ_FILE, sock_in, 0); + fromhost(&req); + + if (!hosts_access(&req)) { + debug("Connection refused by tcp wrapper"); + refuse(&req); + /* NOTREACHED */ + fatal("libwrap refuse returns"); + } + } +#endif /* LIBWRAP */ + check_ip_options(ssh); /* Prepare the channels layer */ --- ./sshd.8.orig 2018-08-23 00:41:42.000000000 -0500 +++ ./sshd.8 2018-08-25 19:12:52.899002527 -0500 @@ -873,6 +873,12 @@ This file should be writable only by the user, and need not be readable by anyone else. .Pp +.It Pa /etc/hosts.allow +.It Pa /etc/hosts.deny +Access controls that should be enforced by tcp-wrappers are defined here. +Further details are described in +.Xr hosts_access 5 . +.Pp .It Pa /etc/hosts.equiv This file is for host-based authentication (see .Xr ssh 1 ) . @@ -975,6 +981,7 @@ .Xr ssh-keygen 1 , .Xr ssh-keyscan 1 , .Xr chroot 2 , +.Xr hosts_access 5 , .Xr login.conf 5 , .Xr moduli 5 , .Xr sshd_config 5 ,