diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..544d21f
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,11 @@
+root = true
+
+[*]
+end_of_line = lf
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[{*.c,*.h}]
+indent_style = space
+indent_size = 4
+tab_width = 8
diff --git a/.gitignore b/.gitignore
index 7a98dc8..bb95251 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,9 @@
-/MCONFIG
-/aconfig.h
-/aconfig.h.in
+/config/MCONFIG
+/config/config.h
+/config/config.h.in
+/autoconf/aclocal.m4
+/autoconf/clean.sh
+/autoconf/helpers/
 /autom4te.cache
 /config.log
 /config.status
@@ -12,5 +15,7 @@
 *.8
 *.a
 *.o
+*.i
+*.s
 *~
 \#*
diff --git a/CHANGES b/CHANGES
index 6df0d97..6b7b53c 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,8 @@
+Changes in 5.2:
+	Fix breakage on newer Linux when a single interface has
+	multiple IP addresses.
+
+
 Changes in 5.1:
 	Add -P option to write a PID file.  Patch by Ferenc Wagner.
 
diff --git a/Makefile b/Makefile
index 9ff12d8..2e790fd 100644
--- a/Makefile
+++ b/Makefile
@@ -3,10 +3,10 @@
 
 SUB =   lib common tftp tftpd
 
-%.build: MCONFIG aconfig.h version.h
+%.build: config/MCONFIG config/config.h version.h
 	$(MAKE) -C $(patsubst %.build, %, $@)
 
-%.install: MCONFIG aconfig.h version.h
+%.install: config/MCONFIG config/config.h version.h
 	$(MAKE) -C $(patsubst %.install, %, $@) install
 
 %.clean:
@@ -15,12 +15,12 @@ SUB =   lib common tftp tftpd
 %.distclean:
 	$(MAKE) -C $(patsubst %.distclean, %, $@) distclean
 
-all:      MCONFIG $(patsubst %, %.build, $(SUB))
+all:      config/MCONFIG $(patsubst %, %.build, $(SUB))
 
 tftp.build: lib.build common.build
 tftpd.build: lib.build common.build
 
-install:  MCONFIG $(patsubst %, %.install, $(SUB))
+install:  config/MCONFIG $(patsubst %, %.install, $(SUB))
 
 clean:	localclean $(patsubst %, %.clean, $(SUB))
 
@@ -30,46 +30,40 @@ localclean:
 distclean: localdistclean $(patsubst %, %.distclean, $(SUB))
 
 localdistclean: localclean
-	rm -f MCONFIG config.status config.log aconfig.h *~ \#*
+	rm -f config/config/MCONFIG config.status config.log config/config.h *~ \#*
 	rm -rf *.cache
 	find . -type f \( -name \*.orig -o -name \*.rej \) | xargs rm -f
 
 spotless: distclean
-	rm -f configure aconfig.h.in tftp.spec
+	rm -f configure config/config.h.in tftp.spec
 
-autoconf: configure aconfig.h.in
+autoconf: configure config/config.h.in
 
-config:	MCONFIG aconfig.h
+config:	config/MCONFIG config/config.h
 
 release:
 	$(MAKE) autoconf
 	$(MAKE) tftp.spec
 	$(MAKE) distclean
 
-MCONFIG: configure MCONFIG.in aconfig.h.in
+config/MCONFIG: configure config/MCONFIG.in config/config.h.in
 	if test -x config.status; then \
 		./config.status --recheck && ./config.status ; \
 	else \
 		./configure ; \
 	fi
 
-aconfig.h: MCONFIG
+config/config.h: config/MCONFIG
 	: Generated by side effect
 
-# Adding "configure" to the dependencies serializes this with running
-# autoconf, because there are apparently race conditions between
-# autoconf and autoheader.
-aconfig.h.in: configure.in configure aclocal.m4
-	rm -f aconfig.h.in aconfig.h
-	autoheader
+configure: configure.ac
+	sh autogen.sh
 
-configure: configure.in aclocal.m4
-	rm -rf MCONFIG configure config.log aconfig.h *.cache
-	autoconf
+config/config.h.in: configure
+	: Generated by side effect
 
 version.h: version
 	echo \#define VERSION \"tftp-hpa `cat version`\" > version.h
 
 tftp.spec: tftp.spec.in version
 	sed -e "s/@@VERSION@@/`cat version`/g" < $< > $@ || rm -f $@
-
diff --git a/aclocal.m4 b/aclocal.m4
deleted file mode 100644
index c07702c..0000000
--- a/aclocal.m4
+++ /dev/null
@@ -1,280 +0,0 @@
-dnl  -----------------------------------------------------------------------
-dnl    
-dnl    Copyright 1999-2008 H. Peter Anvin - All Rights Reserved
-dnl 
-dnl    This program is free software; you can redistribute it and/or modify
-dnl    it under the terms of the GNU General Public License as published by
-dnl    the Free Software Foundation, Inc., 53 Temple Place Ste 330,
-dnl    Bostom MA 02111-1307, USA; either version 2 of the License, or
-dnl    (at your option) any later version; incorporated herein by reference.
-dnl 
-dnl  -----------------------------------------------------------------------
-
-dnl --------------------------------------------------------------------------
-dnl PA_ADD_CFLAGS()
-dnl
-dnl Attempt to add the given option to CFLAGS, if it doesn't break compilation
-dnl --------------------------------------------------------------------------
-AC_DEFUN(PA_ADD_CFLAGS,
-[AC_MSG_CHECKING([if $CC accepts $1])
- pa_add_cflags__old_cflags="$CFLAGS"
- CFLAGS="$CFLAGS $1"
- AC_TRY_LINK([#include <stdio.h>],
- [printf("Hello, World!\n");],
- AC_MSG_RESULT([yes]),
- AC_MSG_RESULT([no])
- CFLAGS="$pa_add_cflags__old_cflags")])
-
-dnl --------------------------------------------------------------------------
-dnl PA_SIGSETJMP
-dnl
-dnl Do we have sigsetjmp/siglongjmp?  (AC_CHECK_FUNCS doesn't seem to work
-dnl for these particular functions.)
-dnl --------------------------------------------------------------------------
-AC_DEFUN(PA_SIGSETJMP,
-[AC_MSG_CHECKING([for sigsetjmp])
- AC_TRY_LINK([
-#ifdef HAVE_SETJMP_H
-#include <setjmp.h>
-#endif],
- [sigjmp_buf buf;
-  sigsetjmp(buf,1);
-  siglongjmp(buf,2);],
- AC_MSG_RESULT([yes])
- $1,
- AC_MSG_RESULT([no])
- $2)])
-
-dnl --------------------------------------------------------------------------
-dnl PA_MSGHDR_MSG_CONTROL
-dnl
-dnl Does struct msghdr have the msg_control field?
-dnl --------------------------------------------------------------------------
-AH_TEMPLATE([HAVE_MSGHDR_MSG_CONTROL],
-[Define if struct msghdr has the msg_control field.])
-
-AC_DEFUN(PA_MSGHDR_MSG_CONTROL,
- [AC_CHECK_MEMBER(struct msghdr.msg_control,
-  [AC_DEFINE(HAVE_MSGHDR_MSG_CONTROL)],
-  [],
-  [
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-  ])])
-
-dnl ------------------------------------------------------------------------
-dnl  PA_STRUCT_IN_PKTINFO
-dnl 
-dnl Look for definition of struct in_pktinfo, which at least has an
-dnl ipi_addr member.  Some versions of glibc lack struct in_pktinfo;
-dnl if so we need to include the definition ourselves -- but we only
-dnl want to do that if absolutely necessary!
-dnl ------------------------------------------------------------------------
-AH_TEMPLATE([HAVE_STRUCT_IN_PKTINFO],
-[Define if struct in_pktinfo is defined.])
-
-AC_DEFUN(PA_STRUCT_IN_PKTINFO,
- [AC_CHECK_MEMBER(struct in_pktinfo.ipi_addr,
-  [AC_DEFINE(HAVE_STRUCT_IN_PKTINFO)],
-  [],
-  [
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-#include <stdlib.h>
-#include <sys/uio.h>
-  ])])
-
-
-dnl ------------------------------------------------------------------------
-dnl  PA_STRUCT_SOCKADDR_IN6
-dnl
-dnl Look for definition of struct sockaddr_in6, which at least has an
-dnl sin6_addr member
-dnl
-AH_TEMPLATE([HAVE_STRUCT_SOCKADDR_IN6],
-[Define if struct sockaddr_in6 is defined.])
-
-AC_DEFUN(PA_STRUCT_SOCKADDR_IN6,
- [AC_CHECK_MEMBER(struct sockaddr_in6.sin6_addr,
-  [
-   AC_DEFINE(HAVE_STRUCT_SOCKADDR_IN6)
-   HAVE_INET6=true;
-  ],
-  [
-   HAVE_INET6=false;
-  ],
-  [
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-  ])])
-
-dnl ------------------------------------------------------------------------
-dnl  PA_STRUCT_ADDRINFO
-dnl
-dnl Look for definition of struct addrinfo, which at least has an
-dnl ai_addr member
-dnl
-AH_TEMPLATE([HAVE_STRUCT_ADDRINFO],
-[Define if struct addrinfo is defined.])
-
-AC_DEFUN(PA_STRUCT_ADDRINFO,
- [AC_CHECK_MEMBER(struct addrinfo.ai_addr,
-  [AC_DEFINE(HAVE_STRUCT_ADDRINFO)],
-  [],
-  [
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netdb.h>
-  ])])
-
-dnl ------------------------------------------------------------------------
-dnl  PA_STRUCT_IN6_PKTINFO
-dnl
-dnl Look for definition of struct in6_pktinfo, which at least has an
-dnl ipi6_addr member
-dnl
-AH_TEMPLATE([HAVE_STRUCT_IN6_PKTINFO],
-[Define if struct in6_pktinfo is defined.])
-
-AC_DEFUN(PA_STRUCT_IN6_PKTINFO,
- [AC_CHECK_MEMBER(struct in6_pktinfo.ipi6_addr,
-  [AC_DEFINE(HAVE_STRUCT_IN6_PKTINFO)],
-  [],
-  [
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
-  ])])
-
-dnl --------------------------------------------------------------------------
-dnl PA_HAVE_TCPWRAPPERS
-dnl
-dnl Do we have the tcpwrappers -lwrap?  This can't be done using AC_CHECK_LIBS
-dnl due to the need to provide "allow_severity" and "deny_severity" variables
-dnl --------------------------------------------------------------------------
-AH_TEMPLATE([HAVE_TCPWRAPPERS],
-[Define if we have tcpwrappers (-lwrap) and <tcpd.h>.])
-
-AC_DEFUN(PA_HAVE_TCPWRAPPERS,
-[AC_CHECK_LIB([wrap], [main])
- AC_MSG_CHECKING([for tcpwrappers])
- AC_TRY_LINK(
-[
-#include <tcpd.h>
-int allow_severity = 0;
-int deny_severity = 0;
-],
-[
-	hosts_ctl("sample_daemon", STRING_UNKNOWN, STRING_UNKNOWN, STRING_UNKNOWN);
-],
-[
-	AC_DEFINE(HAVE_TCPWRAPPERS)
-	AC_MSG_RESULT([yes])
-],
-[
-	AC_MSG_RESULT([no])
-])])
-
-dnl ------------------------------------------------------------------------
-dnl  PA_CHECK_INTTYPES_H_SANE
-dnl
-dnl  At least some versions of AIX 4 have <inttypes.h> macros which are
-dnl  completely broken.  Try to detect those.
-dnl --------------------------------------------------------------------------
-AH_TEMPLATE([INTTYPES_H_IS_SANE],
-[Define if the macros in <inttypes.h> are usable])
-
-AC_DEFUN(PA_CHECK_INTTYPES_H_SANE,
-[AC_CHECK_HEADERS(inttypes.h,
- [
-  AC_MSG_CHECKING([if inttypes.h is sane])
-  AC_TRY_LINK(
-  [
-#include <inttypes.h>
-#include <stdio.h>
-  ],
-  [uintmax_t max = UINTMAX_C(0);
-   printf("%"PRIuMAX"\n", max);],
-  AC_MSG_RESULT([yes])
-  AC_DEFINE(INTTYPES_H_IS_SANE),
-  AC_MSG_RESULT([no (AIX, eh?)]))
- ])
-])
-
-dnl ------------------------------------------------------------------------
-dnl  PA_WITH_BOOL
-dnl
-dnl  PA_WITH_BOOL(option, default, help, enable, disable)
-dnl
-dnl  Provides a more convenient way to specify --with-option and
-dnl  --without-option, with a default.  default should be either 0 or 1.
-dnl ------------------------------------------------------------------------
-AC_DEFUN(PA_WITH_BOOL,
-[AC_ARG_WITH([$1], [$3],
-if test ["$withval"] != no; then
-[$4]
-else
-[$5]
-fi,
-if test [$2] -ne 0; then
-[$4]
-else
-[$5]
-fi)])
-
-dnl --------------------------------------------------------------------------
-dnl  PA_HEADER_DEFINES
-dnl
-dnl  PA_HEADER_DEFINES(header, type, value)
-dnl --------------------------------------------------------------------------
-AC_DEFUN(PA_HEADER_DEFINES,
-[AC_MSG_CHECKING([if $1 defines $3])
- AH_TEMPLATE([HAVE_$3_DEFINITION], [Define if $1 defines $3])
- AC_TRY_COMPILE([
-#include <$1>
-],
-[
-int main()
-{
-	$2 dummy = $3;
-	return 0;
-}
-],
-[
- pa_header_define=`echo HAVE_$3_DEFINITION | tr '[a-z]' '[A-Z]'`
- AC_DEFINE_UNQUOTED($pa_header_define)
- AC_MSG_RESULT(yes)
-],
-[
- AC_MSG_RESULT(no)
-])])
-
-dnl --------------------------------------------------------------------------
-dnl  PA_SEARCH_LIBS_AND_ADD
-dnl
-dnl  PA_SEARCH_LIBS_AND_ADD(function, libraries [,function to add])
-dnl --------------------------------------------------------------------------
-
-AC_DEFUN(PA_SEARCH_LIBS_AND_ADD,
- [
-  AH_TEMPLATE(AS_TR_CPP(HAVE_$1), [Define if $1 function was found])
-  AC_SEARCH_LIBS($1, $2,
-   [
-    AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_$1))
-    pa_add_$1=false;
-   ],
-   [
-    XTRA=true;
-    if test $# -eq 3; then
-      AC_LIBOBJ($3)
-    else
-      AC_LIBOBJ($1)
-    fi
-    pa_add_$1=true;
-   ])])
diff --git a/autoconf/m4/pa_add_cflags.m4 b/autoconf/m4/pa_add_cflags.m4
new file mode 100644
index 0000000..26d55c4
--- /dev/null
+++ b/autoconf/m4/pa_add_cflags.m4
@@ -0,0 +1,9 @@
+dnl --------------------------------------------------------------------------
+dnl PA_ADD_CFLAGS(variable, flag [,actual_flag [,success [,failure]]]])
+dnl
+dnl Attempt to add the given option to xFLAGS, if it doesn't break
+dnl compilation.  If the option to be tested is different than the
+dnl option that should actually be added, add the option to be
+dnl actually added as a second argument.
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_ADD_CFLAGS], [PA_ADD_FLAGS(CFLAGS, [$1], [$2], [$3], [$4])])
diff --git a/autoconf/m4/pa_add_flags.m4 b/autoconf/m4/pa_add_flags.m4
new file mode 100644
index 0000000..23f96f1
--- /dev/null
+++ b/autoconf/m4/pa_add_flags.m4
@@ -0,0 +1,39 @@
+dnl --------------------------------------------------------------------------
+dnl PA_ADD_FLAGS(flagvar, flags)
+dnl
+dnl  Add [flags] to the variable [flagvar] if and only if it is accepted
+dnl  by all languages affected by [flagvar], if those languages have
+dnl  been previously seen in the script.
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_ADD_FLAGS],
+[
+  AS_VAR_PUSHDEF([old], [_$0_$1_orig])
+  AS_VAR_PUSHDEF([ok], [_$0_$1_ok])
+  AS_VAR_PUSHDEF([flags], [$1])
+
+  AS_VAR_COPY([old], [flags])
+  AS_VAR_SET([flags], ["$flags $2"])
+  AS_VAR_SET([ok], [yes])
+
+  PA_LANG_FOREACH(PA_FLAGS_LANGLIST($1),
+    [AS_VAR_IF([ok], [yes],
+     [AC_MSG_CHECKING([if $]_AC_CC[ accepts $2])
+      PA_BUILD_IFELSE([],
+      [AC_MSG_RESULT([yes])],
+      [AC_MSG_RESULT([no])
+       AS_VAR_SET([ok], [no])])])
+     ])
+
+ AS_VAR_IF([ok], [yes],
+  [m4_ifnblank([$3],[AS_VAR_SET([flags], ["$old $3"])])
+   m4_foreach_w([_pa_add_flags_flag], [m4_ifblank([$3],[$2],[$3])],
+   [AC_DEFINE(PA_SYM([$1_]_pa_add_flags_flag), 1,
+    [Define to 1 if compiled with the ]_pa_add_flags_flag[ compiler flag])])
+   $4],
+  [AS_VAR_SET([flags], ["$old"])
+   $5])
+
+  AS_VAR_POPDEF([flags])
+  AS_VAR_POPDEF([ok])
+  AS_VAR_POPDEF([old])
+])
diff --git a/autoconf/m4/pa_add_headers.m4 b/autoconf/m4/pa_add_headers.m4
new file mode 100644
index 0000000..d3c478a
--- /dev/null
+++ b/autoconf/m4/pa_add_headers.m4
@@ -0,0 +1,13 @@
+dnl --------------------------------------------------------------------------
+dnl PA_ADD_HEADERS(headers...)
+dnl
+dnl Call AC_CHECK_HEADERS(), and add to ac_includes_default if found
+dnl --------------------------------------------------------------------------
+AC_DEFUN([_PA_ADD_HEADER],
+[AC_CHECK_HEADERS([$1],[ac_includes_default="$ac_includes_default
+#include <$1>"
+])
+])
+
+AC_DEFUN([PA_ADD_HEADERS],
+[m4_map_args_w([$1],[_PA_ADD_HEADER(],[)])])
diff --git a/autoconf/m4/pa_add_langflags.m4 b/autoconf/m4/pa_add_langflags.m4
new file mode 100644
index 0000000..05c3114
--- /dev/null
+++ b/autoconf/m4/pa_add_langflags.m4
@@ -0,0 +1,27 @@
+dnl --------------------------------------------------------------------------
+dnl PA_ADD_LANGFLAGS(flag...)
+dnl
+dnl Attempt to add the option in the given list to each compiler flags
+dnl (CFLAGS, CXXFLAGS, ...), if it doesn't break compilation.
+dnl --------------------------------------------------------------------------
+m4_defun([_PA_LANGFLAG_VAR],
+[m4_case([$1],
+ [C], [CFLAGS],
+ [C++], [CXXFLAGS],
+ [Fortran 77], [FFLAGS],
+ [Fortran], [FCFLAGS],
+ [Erlang], [ERLCFLAGS],
+ [Objective C], [OBJCFLAGS],
+ [Objective C++], [OBJCXXFLAGS],
+ [Go], [GOFLAGS],
+ [m4_fatal([PA_ADD_LANGFLAGS: Unknown language: $1])])])
+
+AC_DEFUN([PA_ADD_LANGFLAGS],
+[m4_pushdef([_pa_langflags],m4_dquote($1))dnl
+m4_set_foreach(_PA_LANG_SEEN_SET,[_pa_lang],dnl
+[_pa_flag_found=no
+ m4_foreach_w([_pa_flag], _pa_langflags,
+ [AS_IF([test $_pa_flag_found = no],
+  [PA_ADD_FLAGS(_PA_LANGFLAG_VAR(_pa_lang),_pa_flag,[],[_pa_flag_found=yes])])
+  ])])
+m4_popdef([_pa_langflags])])
diff --git a/autoconf/m4/pa_arg_bool.m4 b/autoconf/m4/pa_arg_bool.m4
new file mode 100644
index 0000000..5289ed4
--- /dev/null
+++ b/autoconf/m4/pa_arg_bool.m4
@@ -0,0 +1,19 @@
+dnl --------------------------------------------------------------------------
+dnl PA_ARG_BOOL(option,helptext,default,enabled_action,disabled_action)
+dnl
+dnl  The last three arguments are optional; default can be yes or no.
+dnl
+dnl  Simpler-to-use versions of AC_ARG_ENABLED, that include the
+dnl  test for $enableval and the AS_HELP_STRING definition. This is only
+dnl  to be used for boolean options.
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_ARG_BOOL],
+[m4_pushdef([pa_default],m4_default(m4_normalize([$3]),[no]))
+ m4_pushdef([pa_option],m4_case(pa_default,[yes],[disable],[enable]))
+ AC_ARG_ENABLE([$1],
+  [AS_HELP_STRING([--]m4_defn([pa_option])[-$1],[$2])],
+  [pa_arg_bool_enableval="$enableval"],
+  [pa_arg_bool_enableval="]m4_defn([pa_default])["])
+ m4_popdef([pa_option], [pa_default])
+ AS_IF([test x"$pa_arg_bool_enableval" != xno], [$4], [$5])
+])
diff --git a/autoconf/m4/pa_arg_disabled.m4 b/autoconf/m4/pa_arg_disabled.m4
new file mode 100644
index 0000000..42f4ce8
--- /dev/null
+++ b/autoconf/m4/pa_arg_disabled.m4
@@ -0,0 +1,4 @@
+dnl --------------------------------------------------------------------------
+dnl PA_ARG_DISABLED(option,helptext,disabled_action,enabled_action)
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_ARG_DISABLED],[PA_ARG_BOOL([$1],[$2],yes,[$4],[$3])])
diff --git a/autoconf/m4/pa_arg_enabled.m4 b/autoconf/m4/pa_arg_enabled.m4
new file mode 100644
index 0000000..7d66a21
--- /dev/null
+++ b/autoconf/m4/pa_arg_enabled.m4
@@ -0,0 +1,4 @@
+dnl --------------------------------------------------------------------------
+dnl PA_ARG_ENABLED(option,helptext,enabled_action,disabled_action)
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_ARG_ENABLED],[PA_ARG_BOOL([$1],[$2],no,[$3],[$4])])
diff --git a/autoconf/m4/pa_build_ifelse.m4 b/autoconf/m4/pa_build_ifelse.m4
new file mode 100644
index 0000000..1aacfcd
--- /dev/null
+++ b/autoconf/m4/pa_build_ifelse.m4
@@ -0,0 +1,16 @@
+dnl --------------------------------------------------------------------------
+dnl PA_BUILD_IFELSE(input [,success [,failure]])
+dnl
+dnl  Same as AC_LINK_IFELSE for languages where linking is applicable,
+dnl  otherwise AC_COMPILE_IFELSE.
+dnl
+dnl If the first argument is empty, use _AC_LANG_IO_PROGRAM.
+dnl --------------------------------------------------------------------------
+m4_defun([_PA_BUILD_IFELSE],
+[m4_case(_AC_LANG,
+ [Erlang], [AC_COMPILE_IFELSE($@)],
+ [AC_LINK_IFELSE($@)])])
+
+AC_DEFUN([PA_BUILD_IFELSE],
+[_PA_BUILD_IFELSE([m4_ifblank([$1],[AC_LANG_SOURCE(_AC_LANG_IO_PROGRAM)],
+ [$1])],[$2],[$3])])
diff --git a/autoconf/m4/pa_c_typeof.m4 b/autoconf/m4/pa_c_typeof.m4
new file mode 100644
index 0000000..909b171
--- /dev/null
+++ b/autoconf/m4/pa_c_typeof.m4
@@ -0,0 +1,32 @@
+dnl --------------------------------------------------------------------------
+dnl PA_C_TYPEOF
+dnl
+dnl Find if typeof() exists, or an equivalent (__typeof__, decltype,
+dnl __decltype__)
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_C_TYPEOF],
+[AC_CACHE_CHECK([if $CC supports typeof], [pa_cv_typeof],
+ [pa_cv_typeof=no
+ for pa_typeof_try in typeof __typeof __typeof__ decltype __decltype __decltype__ _Decltype
+ do
+  AS_IF([test $pa_cv_typeof = no],
+        [AC_COMPILE_IFELSE([AC_LANG_SOURCE([
+AC_INCLUDES_DEFAULT
+int testme(int x);
+int testme(int x)
+{
+    $pa_typeof_try(x) y = x*x;
+    return y;
+}
+])],
+ [pa_cv_typeof=$pa_typeof_try])])
+ done
+ ])
+ AS_IF([test $pa_cv_typeof = no],
+       [],
+       [AC_DEFINE([HAVE_TYPEOF], 1,
+	 [Define to 1 if you have some version of the typeof operator.])
+	AS_IF([test $pa_cv_typeof = typeof],
+	      [],
+	      [AC_DEFINE_UNQUOTED([typeof], [$pa_cv_typeof],
+	        [Define if your typeof operator is not named `typeof'.])])])])
diff --git a/autoconf/m4/pa_check_bad_stdc_inline.m4 b/autoconf/m4/pa_check_bad_stdc_inline.m4
new file mode 100644
index 0000000..3fbc53a
--- /dev/null
+++ b/autoconf/m4/pa_check_bad_stdc_inline.m4
@@ -0,0 +1,26 @@
+dnl --------------------------------------------------------------------------
+dnl PA_CHECK_BAD_STDC_INLINE
+dnl
+dnl Some versions of gcc seem to apply -Wmissing-prototypes to C99
+dnl inline functions, which means we need to use GNU inline syntax
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_CHECK_BAD_STDC_INLINE],
+[AC_MSG_CHECKING([if $CC supports C99 external inlines])
+ AC_COMPILE_IFELSE([AC_LANG_SOURCE([
+AC_INCLUDES_DEFAULT
+
+/* Don't mistake GNU inlines for c99 */
+#if defined(__GNUC__) && !defined(__GNUC_STDC_INLINE__)
+# error "Using gnu inline standard"
+#endif
+
+inline int foo(int x)
+{
+	return x+1;
+}
+ ])],
+ [AC_MSG_RESULT([yes])
+  AC_DEFINE([HAVE_STDC_INLINE], 1,
+    [Define to 1 if your compiler supports C99 extern inline])],
+ [AC_MSG_RESULT([no])
+  PA_ADD_CFLAGS([-fgnu89-inline])])])
diff --git a/autoconf/m4/pa_check_inttypes_h_sane.m4 b/autoconf/m4/pa_check_inttypes_h_sane.m4
new file mode 100644
index 0000000..589e0a2
--- /dev/null
+++ b/autoconf/m4/pa_check_inttypes_h_sane.m4
@@ -0,0 +1,17 @@
+dnl ------------------------------------------------------------------------
+dnl  PA_CHECK_INTTYPES_H_SANE
+dnl
+dnl  At least some versions of AIX 4 have <inttypes.h> macros which are
+dnl  completely broken.  Try to detect those.
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_CHECK_INTTYPES_H_SANE],
+[AC_CHECK_HEADERS_ONCE(inttypes.h)
+AS_IF([test "x$ac_cv_header_inttypes_h" = xyes],[
+  AC_MSG_CHECKING([if inttypes.h is sane])
+  AC_LINK_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
+  [uintmax_t max = UINTMAX_C(0);
+   printf("%"PRIuMAX"\n", max);])],
+  [AC_MSG_RESULT([yes])
+   AC_DEFINE(INTTYPES_H_IS_SANE, 1,
+     [Define if the macros in <inttypes.h> are usable])],
+  [AC_MSG_RESULT([no (AIX, eh?)])])])])
diff --git a/autoconf/m4/pa_cross_compile.m4 b/autoconf/m4/pa_cross_compile.m4
new file mode 100644
index 0000000..f082973
--- /dev/null
+++ b/autoconf/m4/pa_cross_compile.m4
@@ -0,0 +1,41 @@
+dnl --------------------------------------------------------------------------
+dnl  PA_CROSS_COMPILE
+dnl
+dnl Get the canonical name for the build and host (runtime) systems;
+dnl then figure out if this is cross-compilation. Specifically, this
+dnl disables invoking WINE on non-Windows systems which are configured
+dnl to run WINE automatically.
+dnl
+dnl Use PA_CROSS_COMPILE_TOOL if the target system (output of a code-
+dnl generation tool) is applicable.
+dnl
+dnl This doesn't explicitly print any messages as that is automatically
+dnl done elsewhere.
+dnl --------------------------------------------------------------------------
+AC_DEFUN_ONCE([PA_CROSS_COMPILE],
+[
+ AC_BEFORE([$0], [AC_LANG_COMPILER])
+ AC_BEFORE([$0], [AC_LANG])
+ AC_BEFORE([$0], [AC_PROG_CC])
+ AC_BEFORE([$0], [AC_PROG_CPP])
+ AC_BEFORE([$0], [AC_PROG_CXX])
+ AC_BEFORE([$0], [AC_PROG_CXXCPP])
+ AC_BEFORE([$0], [AC_PROG_OBJC])
+ AC_BEFORE([$0], [AC_PROG_OBJCPP])
+ AC_BEFORE([$0], [AC_PROG_OBJCXX])
+ AC_BEFORE([$0], [AC_PROG_OBJCXXCPP])
+ AC_BEFORE([$0], [AC_PROG_F77])
+ AC_BEFORE([$0], [AC_PROG_FC])
+ AC_BEFORE([$0], [AC_PROG_GO])
+
+ # Disable WINE
+ WINELOADER=/dev/null
+ export WINELOADER
+ WINESERVER=/dev/null
+ export WINESERVER
+ WINEPREFIX=/dev/null
+ export WINEPREFIX
+
+ AC_CANONICAL_BUILD
+ AC_CANONICAL_HOST
+])
diff --git a/autoconf/m4/pa_flags_langlist.m4 b/autoconf/m4/pa_flags_langlist.m4
new file mode 100644
index 0000000..2ef5ded
--- /dev/null
+++ b/autoconf/m4/pa_flags_langlist.m4
@@ -0,0 +1,19 @@
+dnl --------------------------------------------------------------------------
+dnl PA_FLAGS_LANGLIST(flagvar)
+dnl
+dnl  Return a list of languages affected by the variable flagvar.
+dnl  If flagvar is unknown, assume it affects the current language.
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_FLAGS_LANGLIST],
+[m4_dquote(m4_case([$1],
+	[CPPFLAGS], [[C],[C++],[Objective C],[Objective C++]],
+	[CFLAGS], [[C]],
+	[CXXFLAGS], [[C++]],
+	[FFLAGS], [[Fortran 77]],
+	[FCFLAGS], [[Fortran]],
+	[ERLCFLAGS], [[Erlang]],
+	[OBJCFLAGS], [[Objective C]],
+	[OBJCXXFLAGS], [[Objective C++]],
+	[GOFLAGS], [[Go]],
+	[LDFLAGS], [[C],[C++],[Fortran 77],[Fortran],[Objective C],[Objective C++],[Go]],
+	m4_dquote(_AC_LANG)))])
diff --git a/autoconf/m4/pa_have_tcpwrappers.m4 b/autoconf/m4/pa_have_tcpwrappers.m4
new file mode 100644
index 0000000..fba87ce
--- /dev/null
+++ b/autoconf/m4/pa_have_tcpwrappers.m4
@@ -0,0 +1,26 @@
+dnl --------------------------------------------------------------------------
+dnl PA_HAVE_TCPWRAPPERS
+dnl
+dnl Do we have the tcpwrappers -lwrap?  This can't be done using AC_CHECK_LIBS
+dnl due to the need to provide "allow_severity" and "deny_severity" variables
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_HAVE_TCPWRAPPERS],
+[AC_CHECK_LIB([wrap], [main])
+ AC_MSG_CHECKING([for tcpwrappers])
+ AC_LINK_IFELSE([AC_LANG_PROGRAM(
+  [[
+#include <tcpd.h>
+int allow_severity = 0;
+int deny_severity = 0;
+  ]],
+  [[
+	hosts_ctl("sample_daemon", STRING_UNKNOWN, STRING_UNKNOWN, STRING_UNKNOWN);
+  ]])],
+ [
+	AC_DEFINE(HAVE_TCPWRAPPERS, 1,
+	[Define if we have tcpwrappers (-lwrap) and <tcpd.h>.])
+	AC_MSG_RESULT([yes])
+ ],
+ [
+	AC_MSG_RESULT([no])
+ ])])
diff --git a/autoconf/m4/pa_lang_foreach.m4 b/autoconf/m4/pa_lang_foreach.m4
new file mode 100644
index 0000000..650913d
--- /dev/null
+++ b/autoconf/m4/pa_lang_foreach.m4
@@ -0,0 +1,15 @@
+dnl --------------------------------------------------------------------------
+dnl PA_LANG_FOREACH(subset, body)
+dnl
+dnl  Expand [body] for each language encountered in the configure script also
+dnl  present in [subset], or all if [subset] is empty
+dnl --------------------------------------------------------------------------
+AC_DEFUN([_PA_LANG_DO],dnl
+[AC_LANG([$2])dnl
+$1])
+
+AC_DEFUN([PA_LANG_FOREACH],dnl
+[m4_pushdef([_pa_lang_foreach_current],[_AC_LANG])dnl
+m4_map_args([m4_curry([_PA_LANG_DO],[$2])],m4_unquote(PA_LANG_SEEN_LIST($1)))dnl
+AC_LANG(_pa_lang_foreach_current)dnl
+m4_popdef([_pa_lang_foreach_current])])
diff --git a/autoconf/m4/pa_lang_seen_list.m4 b/autoconf/m4/pa_lang_seen_list.m4
new file mode 100644
index 0000000..d524013
--- /dev/null
+++ b/autoconf/m4/pa_lang_seen_list.m4
@@ -0,0 +1,20 @@
+dnl --------------------------------------------------------------------------
+dnl PA_LANG_SEEN_LIST(subset)
+dnl
+dnl  List of the language lang has been used in the configuration
+dnl  script so far, possibly subset by [subset].
+dnl
+dnl This relies on overriding _AC_LANG_SET(from, to),
+dnl the internal implementation of _AC_LANG.
+dnl --------------------------------------------------------------------------
+m4_ifndef([_PA_LANG_SET],
+[m4_rename([_AC_LANG_SET], [_PA_LANG_SET])dnl
+m4_defun([_AC_LANG_SET], [m4_set_add([_PA_LANG_SEEN_SET],[$2])dnl
+_PA_LANG_SET($@)])])
+
+AC_DEFUN([PA_LANG_SEEN_LIST],
+[m4_set_delete([_pa_lang_seen_subset])dnl
+m4_pushdef([_pa_lang_seen_subset_list],m4_ifnblank([$1],[$1],m4_dquote(m4_set_list([_PA_LANG_SEEN_SET]))))dnl
+m4_set_add_all([_pa_lang_seen_subset],_pa_lang_seen_subset_list)dnl
+m4_cdr(m4_set_intersection([_pa_lang_seen_subset],[_PA_LANG_SEEN_SET]))dnl
+m4_popdef([_pa_lang_seen_subset_list])])
diff --git a/autoconf/m4/pa_option_debug.m4 b/autoconf/m4/pa_option_debug.m4
new file mode 100644
index 0000000..ae7d9db
--- /dev/null
+++ b/autoconf/m4/pa_option_debug.m4
@@ -0,0 +1,13 @@
+dnl --------------------------------------------------------------------------
+dnl PA_OPTION_DEBUG(with_debug, without_debug)
+dnl
+dnl Set debug flags and optimization flags depending on if
+dnl --enable-debug is set or not. Some flags are set regardless...
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_OPTION_DEBUG],
+[PA_ARG_DISABLED([gdb], [disable gdb debug extensions],
+ [PA_ADD_LANGFLAGS([-g3])], [PA_ADD_LANGFLAGS([-ggdb3 -g3])])
+ PA_ARG_ENABLED([debug], [optimize for debugging],
+ [PA_ADD_LANGFLAGS([-Og -O0])
+  $1],
+ [$2])])
diff --git a/autoconf/m4/pa_option_profiling.m4 b/autoconf/m4/pa_option_profiling.m4
new file mode 100644
index 0000000..39a3f6c
--- /dev/null
+++ b/autoconf/m4/pa_option_profiling.m4
@@ -0,0 +1,8 @@
+dnl --------------------------------------------------------------------------
+dnl PA_OPTION_PROFILING(with_profiling, without_profiling)
+dnl
+dnl Try to enable profiling if --enable-profiling is set.
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_OPTION_PROFILING],
+[PA_ARG_ENABLED([profiling], [compile with profiling (-pg option)],
+[PA_ADD_LANGFLAGS([-pg])])])
diff --git a/autoconf/m4/pa_prog_cc.m4 b/autoconf/m4/pa_prog_cc.m4
new file mode 100644
index 0000000..0debe5d
--- /dev/null
+++ b/autoconf/m4/pa_prog_cc.m4
@@ -0,0 +1,13 @@
+dnl --------------------------------------------------------------------------
+dnl PA_PROG_CC()
+dnl
+dnl Similar to AC_PROG_CC, but add a prototype for main() to
+dnl AC_INCLUDES_DEFAULT to avoid -Werror from breaking compilation.
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_PROG_CC],
+[AC_PROG_CC
+ AS_IF([test x$ac_cv_prog != xno],
+ [ac_includes_default="$ac_includes_default
+#ifndef __cplusplus
+extern int main(void);
+#endif"])])
diff --git a/autoconf/m4/pa_search_libs_and_add.m4 b/autoconf/m4/pa_search_libs_and_add.m4
new file mode 100644
index 0000000..b006128
--- /dev/null
+++ b/autoconf/m4/pa_search_libs_and_add.m4
@@ -0,0 +1,22 @@
+dnl --------------------------------------------------------------------------
+dnl  PA_SEARCH_LIBS_AND_ADD
+dnl
+dnl  PA_SEARCH_LIBS_AND_ADD(function, libraries [,function to add])
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_SEARCH_LIBS_AND_ADD],
+ [
+  AH_TEMPLATE(AS_TR_CPP(HAVE_$1), [Define if $1 function was found])
+  AC_SEARCH_LIBS($1, $2,
+   [
+    AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_$1))
+    pa_add_$1=false;
+   ],
+   [
+    XTRA=true;
+    if test $# -eq 3; then
+      AC_LIBOBJ($3)
+    else
+      AC_LIBOBJ($1)
+    fi
+    pa_add_$1=true;
+   ])])
diff --git a/autoconf/m4/pa_sigsetjmp.m4 b/autoconf/m4/pa_sigsetjmp.m4
new file mode 100644
index 0000000..898b562
--- /dev/null
+++ b/autoconf/m4/pa_sigsetjmp.m4
@@ -0,0 +1,25 @@
+dnl --------------------------------------------------------------------------
+dnl PA_SIGSETJMP
+dnl
+dnl Do we have sigsetjmp/siglongjmp?  (AC_CHECK_FUNCS doesn't seem to work
+dnl for these particular functions.)
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_SIGSETJMP],
+[AC_MSG_CHECKING([for sigsetjmp])
+ AC_LINK_IFELSE([AC_LANG_SOURCE(
+[
+AC_INCLUDES_DEFAULT
+#include <setjmp.h>
+
+int main(void) {
+	sigjmp_buf buf;
+	if (sigsetjmp(buf,1))
+		return 0;
+	siglongjmp(buf,2);
+	return 1;
+  }
+])],
+ [AC_MSG_RESULT([yes])
+  AC_DEFINE([HAVE_SIGSETJMP], 1,
+    [Define to 1 if your system has sigsetjmp/siglongjmp])],
+ [AC_MSG_RESULT([no])])])
diff --git a/autoconf/m4/pa_sym.m4 b/autoconf/m4/pa_sym.m4
new file mode 100644
index 0000000..d3a8965
--- /dev/null
+++ b/autoconf/m4/pa_sym.m4
@@ -0,0 +1,11 @@
+dnl --------------------------------------------------------------------------
+dnl PA_SYM(prefix, string)
+dnl
+dnl Convert a (semi-) arbitrary string to a CPP symbol
+dnl Compact underscores and convert non-C characters to underscore,
+dnl except + which is converted to X (so C++ -> CXX).
+dnl --------------------------------------------------------------------------
+AC_DEFUN([PA_SYM],
+[m4_bpatsubsts(m4_quote(m4_toupper([$*])),
+ [,],[],[\+],[X],[[^ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789]+],[_],dnl
+[^._?\(.*\)_.$],[[\1]])])
diff --git a/autogen.sh b/autogen.sh
index 728a381..0c892cc 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -1,2 +1,83 @@
-#!/bin/sh
-make autoconf
+#!/bin/sh -x
+#
+# Run this script to regenerate autoconf files
+#
+recheck=false
+for arg; do
+    case x"$arg" in
+	x--recheck)
+	    recheck=true
+	    config=$(sh config.status --config 2>/dev/null)
+	    ;;
+	x--clearenv)
+	    unset AUTOCONF AUTOMAKE ACLOCAL AUTOHEADER ACLOCAL_PATH
+	    ;;
+	*)
+	    echo "$0: unknown option: $arg" 1>&2
+	    ;;
+    esac
+done
+
+# This allows for overriding the default autoconf programs
+AUTOCONF="${AUTOCONF:-${AUTOTOOLS_PREFIX}autoconf}"
+AUTOMAKE="${AUTOMAKE:-${AUTOTOOLS_PREFIX}automake}"
+ACLOCAL="${ACLOCAL:-${AUTOTOOLS_PREFIX}aclocal}"
+AUTOHEADER="${AUTOHEADER:-${AUTOTOOLS_PREFIX}autoheader}"
+
+mkdir -p autoconf autoconf/helpers config
+autolib="`"$AUTOMAKE" --print-libdir`"
+if test ! x"$autolib" = x; then
+    for prg in install-sh compile config.guess config.sub; do
+	# Update autoconf helpers if and only if newer ones are available
+	if test -f "$autolib"/"$prg" && \
+		( set -e ; \
+		  test -f autoconf/helpers/"$prg" && sed -n \
+		    -e 's/^scriptver=/scriptversion=/' \
+		    -e 's/^timestamp=/scriptversion=/' \
+		    -e 's/^scriptversion=['\''"]?\([^'\''"]*\).*$/\1/p' \
+			  "$autolib"/"$prg" autoconf/helpers/"$prg" | \
+			  sort -c 2>/dev/null ; \
+		  test $? -ne 0 )
+	then
+	    cp -f "$autolib"/"$prg" autoconf/helpers
+	fi
+    done
+fi
+mv -f autoconf/aclocal.m4 autoconf/aclocal.m4.old
+mkdir -p autoconf/m4.old autoconf/m4
+mv -f autoconf/m4/*.m4 autoconf/m4.old/ 2>/dev/null || true
+ACLOCAL_PATH="${ACLOCAL_PATH}${ACLOCAL_PATH:+:}`pwd`/autoconf/m4.old"
+export ACLOCAL_PATH
+"$ACLOCAL" --install --output=autoconf/aclocal.m4 -I autoconf/m4
+if test ! -f autoconf/aclocal.m4; then
+    # aclocal failed, revert to previous files
+    mv -f autoconf/m4.old/*.m4 autoconf/m4/
+    mv -f autoconf/aclocal.m4.old autoconf/aclocal.m4
+    exit 1
+fi
+rm -rf autoconf/*m4.old
+"$AUTOHEADER" -B autoconf
+"$AUTOCONF" -B autoconf
+(
+    echo '#!/bin/sh'
+    "$AUTOCONF" -B autoconf \
+		-t AC_CONFIG_HEADERS:'rm -f $*' \
+		-t AC_CONFIG_FILES:'rm -f $*'
+    echo 'rm -f config.log config.status'
+    echo 'rm -rf autom4te.cache'
+) > autoconf/clean.sh
+chmod +x autoconf/clean.sh
+sh autoconf/clean.sh
+
+rm -f configure~ || true
+
+# Try to regenerate unconfig.h if Perl is available and unconfig.pl
+# is present in the autoconf directory.
+if [ -n "$(which perl)" -a -f autoconf/unconfig.pl ]; then
+    perl autoconf/unconfig.pl . config/config.h.in config/unconfig.h
+fi
+
+if $recheck; then
+    # This bizarre statement has to do with how config.status quotes its output
+    echo exec sh configure $config | sh -
+fi
diff --git a/common/Makefile b/common/Makefile
index a825213..89e351d 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -1,10 +1,10 @@
 SRCROOT = ..
 VERSION = $(shell cat ../version)
 
--include ../MCONFIG
+-include ../config/MCONFIG
 include ../MRULES
 
-OBJS = tftpsubs.$(O)
+OBJS = tftpsubs.$(O) signal.$(O)
 LIB  = libcommon.a
 
 all: $(LIB)
diff --git a/common/signal.c b/common/signal.c
new file mode 100644
index 0000000..ccd4af8
--- /dev/null
+++ b/common/signal.c
@@ -0,0 +1,19 @@
+/*
+ * signal.c
+ *
+ * User-friendly wrapper around sigaction().
+ */
+
+#include "config.h"
+
+int tftp_signal(int signum, sighandler_t handler, int flags)
+{
+    struct sigaction sa;
+
+    memset(&sa, 0, sizeof sa);
+    sa.sa_handler = handler;
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = flags;
+
+    return sigaction(signum, &sa, NULL);
+}
diff --git a/config.h b/config.h
index 0e35438..a8c55ac 100644
--- a/config.h
+++ b/config.h
@@ -1,6 +1,6 @@
 /* -*- c -*- ------------------------------------------------------------- *
  *
- *   Copyright 2001-2006 H. Peter Anvin - All Rights Reserved
+ *   Copyright 2001-2024 H. Peter Anvin - All Rights Reserved
  *
  *   This program is free software available under the same license
  *   as the "OpenBSD" operating system, distributed at
@@ -17,12 +17,23 @@
 #ifndef CONFIG_H
 #define CONFIG_H 1
 
+/* Feature enables for specific environments */
+#ifdef __APPLE__
+#if __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 1070
+#define __APPLE_USE_RFC_3542 1
+#endif
+#endif
+
 /* Must be included before we include any system headers! */
-#include "aconfig.h"            /* autogenerated configuration header */
+#include "config/config.h"            /* autogenerated configuration header */
 
 /* Standard includes */
 
 #include <stdio.h>
+#include <time.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <signal.h>
 
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
@@ -32,21 +43,6 @@
 #include <sys/stat.h>
 #endif
 
-#ifdef STDC_HEADERS
-#include <stdlib.h>
-#include <stddef.h>
-#else
-#ifdef HAVE_STDLIB_H
-#include <stdlib.h>
-#endif
-#endif
-
-#ifdef HAVE_MEMORY_H
-#ifndef STDC_HEADERS
-#include <memory.h>
-#endif
-#endif
-
 #ifdef HAVE_STRING_H
 #include <string.h>
 #endif
@@ -73,15 +69,8 @@
 #include <setjmp.h>
 #endif
 
-#ifdef TIME_WITH_SYS_TIME
+#ifdef HAVE_SYS_TIME_H
 #include <sys/time.h>
-#include <time.h>
-#else
-#if HAVE_SYS_TIME_H
-#include <sys/time.h>
-#else
-#include <time.h>
-#endif
 #endif
 
 #ifdef HAVE_GRP_H
@@ -92,9 +81,6 @@
 #include <fcntl.h>
 #endif
 
-#include <errno.h>
-#include <signal.h>
-
 #ifdef HAVE_SYS_SOCKET_H
 #include <sys/socket.h>
 #else
@@ -129,10 +115,10 @@
 
 /* Some broken systems care about text versus binary, but
    real Unix systems don't... */
-#ifndef HAVE_O_TEXT_DEFINITION
+#if !HAVE_DECL_O_TEXT
 #define O_TEXT		0
 #endif
-#ifndef HAVE_O_BINARY_DEFINITION
+#if !HAVE_DECL_O_BINARY
 #define O_BINARY	0
 #endif
 
@@ -267,11 +253,9 @@ typedef int socklen_t;
 
 #include <netinet/in.h>
 
-#ifndef HAVE_IPPORT_TFTP_DEFINITION
-#ifndef IPPORT_TFTP
+#if !HAVE_DECL_IPPORT_TFTP && !defined(IPPORT_TFTP)
 #define IPPORT_TFTP 69
 #endif
-#endif
 
 /* arpa/{inet,tftp}.h, and possible missing pieces */
 
@@ -293,9 +277,11 @@ typedef int socklen_t;
 void *xmalloc(size_t);
 char *xstrdup(const char *);
 
-#ifndef HAVE_BSD_SIGNAL
-void (*bsd_signal(int, void (*)(int))) (int);
+#ifndef HAVE_SIGHANDLER_T
+typedef void (*sighandler_t)(int);
 #endif
+int tftp_signal(int, sighandler_t, int);
+
 #ifndef HAVE_DUP2
 int dup2(int, int);
 #endif
diff --git a/MCONFIG.in b/config/MCONFIG.in
similarity index 100%
rename from MCONFIG.in
rename to config/MCONFIG.in
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..deaa4fc
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,283 @@
+dnl Process this file with autoconf 2.71 or later to produce
+dnl a configure script.
+AC_PREREQ([2.71])
+AC_INIT
+AC_CONFIG_SRCDIR([MRULES])
+AC_PREFIX_DEFAULT([/usr])
+AC_CONFIG_AUX_DIR([autoconf/helpers])
+
+dnl This prevents us from running Wine and thinking we are not
+dnl cross-compiling when in fact we are; running Wine here is at
+dnl the best very slow and doesn't buy us a single thing at all.
+PA_CROSS_COMPILE
+
+dnl Enable any available C extensions
+PA_PROG_CC
+AC_USE_SYSTEM_EXTENSIONS
+
+dnl Options for debugging and profiling
+PA_OPTION_DEBUG
+PA_OPTION_PROFILING
+
+dnl LLVM doesn't error out on invalid -W options unless this option is
+dnl specified first.  Enable this so this script can actually discover
+dnl which -W options are possible for this compiler.
+PA_ADD_CFLAGS([-Werror=unknown-warning-option])
+
+dnl Force gcc and gcc-compatible compilers treat signed integers
+dnl as 2's complement
+PA_ADD_CFLAGS([-fwrapv])
+
+dnl Force clang to behave in a predictable manner, in order to make bugs
+dnl possible to track down. gcc appears to have this behavior by default.
+PA_ADD_CFLAGS([-ftrivial-auto-var-init=zero])
+
+dnl Some environments abuse __STRICT_ANSI__ to disable some
+dnl function declarations
+PA_ADD_CFLAGS([-U__STRICT_ANSI__])
+
+dnl Don't put things in common if we can avoid it.  We don't want to
+dnl assume all compilers support common, and this will help find those
+dnl problems.  This also works around an OSX linker problem.
+PA_ADD_CFLAGS([-fno-common])
+
+dnl Tests which may trigger warnings on some compilers
+AC_C_CONST
+AC_C_INLINE
+AC_C_RESTRICT
+
+dnl Checks for header files.
+AC_CHECK_INCLUDES_DEFAULT
+
+dnl See if we need extra libraries
+XTRA=false
+
+AC_SEARCH_LIBS([strerror],[cposix])
+
+AC_CHECK_HEADERS_ONCE(inttypes.h)
+AC_CHECK_HEADERS_ONCE(stdint.h)
+AC_CHECK_HEADERS_ONCE(grp.h)
+AC_CHECK_HEADERS_ONCE(libgen.h)
+AC_CHECK_HEADERS_ONCE(setjmp.h)
+AC_CHECK_HEADERS_ONCE(strings.h)
+AC_CHECK_HEADERS_ONCE(sysexits.h)
+AC_CHECK_HEADERS_ONCE(unistd.h)
+AC_CHECK_HEADERS_ONCE(sys/filio.h)
+AC_CHECK_HEADERS_ONCE(sys/stat.h)
+AC_CHECK_HEADERS_ONCE(sys/time.h)
+PA_CHECK_INTTYPES_H_SANE
+
+dnl This is needed on some versions of FreeBSD...
+AC_CHECK_HEADERS_ONCE(machine/param.h)
+
+dnl Windows...
+PA_ADD_HEADERS(windows.h)
+PA_ADD_HEADERS(winsock2.h)
+AS_IF([test "x$ac_cv_header_winsock2_h" != xyes],
+      [PA_ADD_HEADERS(winsock.h)])
+
+PA_ADD_HEADERS(fcntl.h)
+PA_ADD_HEADERS(sys/types.h)
+PA_ADD_HEADERS(arpa/inet.h)
+PA_ADD_HEADERS(sys/socket.h)
+PA_ADD_HEADERS(sys/file.h)
+PA_ADD_HEADERS(netinet/in.h)
+PA_ADD_HEADERS(sys/uio.h)
+PA_ADD_HEADERS(netdb.h)
+
+AC_TYPE_OFF_T
+AC_TYPE_PID_T
+AC_TYPE_MODE_T
+AC_TYPE_SIZE_T
+AC_CHECK_TYPES(intmax_t)
+AC_CHECK_TYPES(long long)
+AC_CHECK_TYPES(uint16_t)
+AC_CHECK_TYPES(uint32_t)
+AC_CHECK_TYPES(u_short)
+AC_CHECK_TYPES(u_long)
+
+AC_CHECK_TYPES(socklen_t)
+
+AC_SEARCH_LIBS(socket, [socket ws2_32 wsock32], ,
+ [AC_MSG_ERROR(socket library not found)])
+
+AC_CHECK_FUNCS(fcntl)
+AC_CHECK_FUNCS(flock)
+AC_CHECK_FUNCS(setsid)
+AC_CHECK_FUNCS(recvmsg)
+AC_CHECK_FUNCS(ftruncate)
+AC_CHECK_FUNCS(setresuid)
+AC_CHECK_FUNCS(setreuid)
+AC_CHECK_FUNCS(setresgid)
+AC_CHECK_FUNCS(setregid)
+AC_CHECK_FUNCS(initgroups)
+AC_CHECK_FUNCS(setgroups)
+AC_CHECK_TYPES(sighandler_t)
+
+dnl Solaris 8 has [u]intmax_t but not strtoumax().  How utterly braindamaged.
+AC_CHECK_FUNCS(strtoumax)
+AC_CHECK_FUNCS(strtoull)
+
+AC_CHECK_MEMBERS(struct msghdr.msg_control)
+AC_CHECK_MEMBERS(struct in_pktinfo.ipi_addr)
+AC_CHECK_MEMBERS(struct addrinfo.ai_addr)
+
+AC_CHECK_DECLS([O_NONBLOCK, O_BINARY, O_TEXT])
+AC_CHECK_DECLS([F_SETLK])
+AC_CHECK_DECLS([LOCK_SH, LOCK_EX])
+
+PA_SIGSETJMP
+
+dnl
+dnl Get common paths
+dnl
+SRCROOT=`cd $srcdir && pwd`
+OBJROOT=`pwd`
+
+PA_SEARCH_LIBS_AND_ADD(xmalloc, iberty)
+PA_SEARCH_LIBS_AND_ADD(xstrdup, iberty)
+PA_SEARCH_LIBS_AND_ADD(getopt_long, getopt, getopt_long)
+PA_SEARCH_LIBS_AND_ADD(getaddrinfo, [nsl resolv])
+AS_IF([$pa_add_getaddrinfo],
+[AC_SEARCH_LIBS(gethostbyname, [nsl resolv],
+      [AC_SEARCH_LIBS(herror, [nsl resolv], ,
+	 [AC_MSG_ERROR(herror not found)])],
+      [AC_MSG_ERROR(gethostbyname not found)])],
+[AC_SEARCH_LIBS(freeaddrinfo, [nsl resolv], ,
+      [AC_MSG_ERROR(getaddrinfo but not freeaddrinfo found)])
+    AC_SEARCH_LIBS(gai_strerror, [nsl resolv], ,
+      [AC_MSG_ERROR(getaddrinfo but not gai_strerror found)])])
+
+PA_SEARCH_LIBS_AND_ADD(inet_ntop, [nsl resolv])
+AS_IF([$pa_add_inet_ntop],
+  [AC_SEARCH_LIBS(inet_ntoa, [nsl resolv], ,
+   [AC_MSG_ERROR(inet_ntoa not found)])])
+
+AC_SEARCH_LIBS(inet_aton, [nsl resolv], ,[AC_MSG_ERROR(inet_aton not found)])
+
+PA_SEARCH_LIBS_AND_ADD(daemon)
+PA_SEARCH_LIBS_AND_ADD(dup2)
+
+AS_IF([$XTRA], [XTRALIBS="$OBJROOT/lib/libxtra.a $XTRALIBS"])
+
+dnl
+dnl These libraries apply to the server only
+dnl
+
+common_libs="$LIBS"
+
+AC_CHECK_DECLS(IPPORT_TFTP)
+
+PA_ARG_DISABLED([tcpwrappers],
+  [disable tcpwrapper permissions checking], [],
+  [
+	AC_SEARCH_LIBS(yp_get_default_domain, [nsl resolv])
+	PA_HAVE_TCPWRAPPERS
+  ])
+
+AC_CHECK_HEADERS_ONCE([regex.h])
+PA_ARG_DISABLED([remap],
+ [disable regex-based filename remapping], [],
+ [AS_IF([test x"$ac_cv_header_regex_h" = xyes],
+  [AC_SEARCH_LIBS(regcomp, [regex rx],
+   [AC_DEFINE([WITH_REGEX], 1,
+	     [Define if we are compiling with regex filename remapping.])
+    TFTPDOBJS="remap.\$(O) $TFTPOBJS"])])])
+
+TFTPD_LIBS="$LIBS $XTRALIBS"
+LIBS="$common_libs"
+
+dnl
+dnl These libraries apply to the client only
+dnl
+
+AH_TEMPLATE([WITH_READLINE],
+[Define if we are compiling with readline/editline command-line editing.])
+
+PA_ARG_DISABLED([readline],
+ [disable the use of readline command-line editing], [],
+ [
+  AC_CHECK_HEADER([readline/readline.h],
+	[
+		dnl readline may need libtermcap or somesuch...
+		AC_SEARCH_LIBS(tputs, [termcap terminfo])
+
+		AC_SEARCH_LIBS(readline, [readline history],
+		[AC_DEFINE(WITH_READLINE)])
+		AC_CHECK_HEADERS(readline/history.h)
+	],
+	[AC_CHECK_HEADER([editline/readline.h],
+	[
+		dnl editline may need libtermcap or somesuch...
+		AC_SEARCH_LIBS(tputs, [termcap terminfo])
+
+		AC_SEARCH_LIBS(editline, [edit],
+		[AC_DEFINE(WITH_READLINE)])
+	])])
+],:)
+
+TFTP_LIBS="$LIBS $XTRALIBS"
+LIBS="$common_libs"
+
+dnl
+dnl   Check for IPV6 and disable-ipv6
+dnl
+
+AC_CHECK_MEMBERS(struct sockaddr_in6.sin6_addr)
+AC_MSG_CHECKING([for IPv6 support])
+PA_ARG_DISABLED([ipv6],
+ [disable support for IPv6],
+ [AC_MSG_RESULT(disabled)],
+ [AS_IF([test x"$ac_cv_member_struct_sockaddr_in6_sin6_addr$ac_cv_member_struct_addrinfo_ai_addr" = xyesyes],
+ [AC_MSG_RESULT(yes)
+  AC_DEFINE(HAVE_IPV6, 1, [define if IPv6 support is enabled])],
+ [AC_MSG_RESULT(no)
+  AC_MSG_WARN([*** we do not have required IPv6 structs - IPv6 will be disabled])])])
+
+AC_SUBST(SRCROOT)
+AC_SUBST(OBJROOT)
+
+AC_SUBST(TFTP_LIBS)
+AC_SUBST(TFTPD_LIBS)
+AC_SUBST(TFTPDOBJS)
+
+AC_PROG_LN_S
+AC_PROG_RANLIB
+
+dnl
+dnl Make sure the install program has an absolute path if it
+dnl has a path at all.  autoconf doesn't do this "in order
+dnl to not pollute the cache."  Sigh.
+dnl Note: the $ needs to be double-quoted for reasons unknown.
+dnl
+AC_PROG_INSTALL
+[if echo "$INSTALL" | grep '^[^/].*/' > /dev/null 2>&1; then
+   INSTALL='\${SRCROOT}'/"$INSTALL"
+fi]
+
+PA_ADD_CFLAGS(-W)
+PA_ADD_CFLAGS(-Wall)
+PA_ADD_CFLAGS(-Wpointer-arith)
+PA_ADD_CFLAGS(-Wbad-function-cast)
+PA_ADD_CFLAGS(-Wcast-equal)
+PA_ADD_CFLAGS(-Wstrict-prototypes)
+PA_ADD_CFLAGS(-Wmissing-prototypes)
+PA_ADD_CFLAGS(-Wmissing-declarations)
+PA_ADD_CFLAGS(-Wnested-externs)
+PA_ADD_CFLAGS(-Winline)
+PA_ADD_CFLAGS(-Wwrite-strings)
+PA_ADD_CFLAGS(-Wundef)
+PA_ADD_CFLAGS(-Wshadow)
+PA_ADD_CFLAGS(-Wsign-compare)
+PA_ADD_CFLAGS(-fno-strict-aliasing)
+
+dnl
+dnl Test compiler features. On some compilers, this can be affected
+dnl by -Werror options, so run this *after* those options are added.
+dnl
+PA_CHECK_BAD_STDC_INLINE
+PA_C_TYPEOF
+
+AC_CONFIG_HEADERS([config/config.h])
+AC_CONFIG_FILES([config/MCONFIG])
+AC_OUTPUT
diff --git a/configure.in b/configure.in
deleted file mode 100644
index 7ab7c5a..0000000
--- a/configure.in
+++ /dev/null
@@ -1,303 +0,0 @@
-dnl
-dnl autoconf input file to generate MCONFIG
-dnl
-
-AC_PREREQ(2.61)
-AC_INIT(MCONFIG.in)
-AC_PREFIX_DEFAULT(/usr)
-
-AC_USE_SYSTEM_EXTENSIONS
-AC_ISC_POSIX
-AC_PROG_CC
-
-AC_C_CONST
-AC_C_INLINE
-
-PA_ADD_CFLAGS(-W)
-PA_ADD_CFLAGS(-Wall)
-PA_ADD_CFLAGS(-Wpointer-arith)
-PA_ADD_CFLAGS(-Wbad-function-cast)
-PA_ADD_CFLAGS(-Wcast-equal)
-PA_ADD_CFLAGS(-Wstrict-prototypes)
-PA_ADD_CFLAGS(-Wmissing-prototypes)
-PA_ADD_CFLAGS(-Wmissing-declarations)
-PA_ADD_CFLAGS(-Wnested-externs)
-PA_ADD_CFLAGS(-Winline)
-PA_ADD_CFLAGS(-Wwrite-strings)
-PA_ADD_CFLAGS(-Wundef)
-PA_ADD_CFLAGS(-Wshadow)
-PA_ADD_CFLAGS(-Wsign-compare)
-PA_ADD_CFLAGS(-pipe)
-PA_ADD_CFLAGS(-fno-strict-aliasing)
-
-AC_HEADER_STDC
-AC_CHECK_HEADERS(inttypes.h)
-AC_CHECK_HEADERS(stdint.h)
-PA_CHECK_INTTYPES_H_SANE
-AC_CHECK_HEADERS(fcntl.h)
-AC_CHECK_HEADERS(grp.h)
-AC_CHECK_HEADERS(libgen.h)
-AC_CHECK_HEADERS(memory.h)
-AC_CHECK_HEADERS(setjmp.h)
-AC_CHECK_HEADERS(stddef.h)
-AC_CHECK_HEADERS(stdlib.h)
-AC_CHECK_HEADERS(string.h)
-AC_CHECK_HEADERS(strings.h)
-AC_CHECK_HEADERS(sysexits.h)
-AC_CHECK_HEADERS(time.h)
-AC_CHECK_HEADERS(unistd.h)
-AC_CHECK_HEADERS(sys/file.h)
-AC_CHECK_HEADERS(sys/filio.h)
-AC_CHECK_HEADERS(sys/stat.h)
-AC_CHECK_HEADERS(sys/time.h)
-AC_CHECK_HEADERS(sys/types.h)
-AC_CHECK_HEADERS(arpa/inet.h)
-AC_CHECK_HEADERS(netdb.h)
-AC_HEADER_TIME
-dnl This is needed on some versions of FreeBSD...
-AC_CHECK_HEADERS(machine/param.h)
-AC_CHECK_HEADERS(sys/socket.h)
-AC_CHECK_HEADERS(winsock2.h)
-AC_CHECK_HEADERS(winsock.h)
-
-AC_SYS_LARGEFILE
-
-AC_TYPE_OFF_T
-AC_TYPE_PID_T
-AC_TYPE_MODE_T
-AC_TYPE_SIZE_T
-AC_CHECK_TYPES(intmax_t)
-AC_CHECK_TYPES(long long)
-AC_CHECK_TYPES(uint16_t)
-AC_CHECK_TYPES(uint32_t)
-AC_CHECK_TYPES(u_short)
-AC_CHECK_TYPES(u_long)
-
-dnl
-dnl <sys/socket.h> isn't among the list of standard headers that autoconf checks,
-dnl but POSIX requires <sys/socket.h> for socklen_t to be defined.
-dnl
-AC_CHECK_TYPES(socklen_t,,,
-[
-#include <stdio.h>
-#if HAVE_SYS_TYPES_H
-# include <sys/types.h>
-#endif
-#if HAVE_SYS_STAT_H
-# include <sys/stat.h>
-#endif
-#if STDC_HEADERS
-# include <stdlib.h>
-# include <stddef.h>
-#else
-# if HAVE_STDLIB_H
-#  include <stdlib.h>
-# endif
-#endif
-#if HAVE_STRING_H
-# if !STDC_HEADERS && HAVE_MEMORY_H
-#  include <memory.h>
-# endif
-# include <string.h>
-#endif
-#if HAVE_STRINGS_H
-# include <strings.h>
-#endif
-#if HAVE_INTTYPES_H
-# include <inttypes.h>
-#else
-# if HAVE_STDINT_H
-#  include <stdint.h>
-# endif
-#endif
-#if HAVE_UNISTD_H
-# include <unistd.h>
-#endif
-#ifdef HAVE_SYS_SOCKET_H
-# include <sys/socket.h>
-#endif
-])
-
-AC_SEARCH_LIBS(socket, [socket ws2_32 wsock32], , [AC_MSG_ERROR(socket library not found)])
-
-AC_CHECK_FUNCS(fcntl)
-AC_CHECK_FUNCS(setsid)
-AC_CHECK_FUNCS(recvmsg)
-AC_CHECK_FUNCS(ftruncate)
-AC_CHECK_FUNCS(setreuid)
-AC_CHECK_FUNCS(setregid)
-AC_CHECK_FUNCS(initgroups)
-AC_CHECK_FUNCS(setgroups)
-
-dnl Solaris 8 has [u]intmax_t but not strtoumax().  How utterly braindamaged.
-AC_CHECK_FUNCS(strtoumax)
-AC_CHECK_FUNCS(strtoull)
-
-PA_MSGHDR_MSG_CONTROL
-PA_STRUCT_IN_PKTINFO
-PA_STRUCT_ADDRINFO
-
-PA_HEADER_DEFINES(fcntl.h, int, O_NONBLOCK)
-PA_HEADER_DEFINES(fcntl.h, int, O_BINARY)
-PA_HEADER_DEFINES(fcntl.h, int, O_TEXT)
-
-PA_HEADER_DEFINES(fcntl.h, int, F_SETLK)
-
-PA_HEADER_DEFINES(sys/file.h, int, LOCK_SH)
-PA_HEADER_DEFINES(sys/file.h, int, LOCK_EX)
-
-AH_TEMPLATE([HAVE_SIGSETJMP],
-[Define if we have sigsetjmp, siglongjmp and sigjmp_buf.])
-PA_SIGSETJMP([AC_DEFINE(HAVE_SIGSETJMP)])
-
-dnl
-dnl Get common paths
-dnl
-SRCROOT=`cd $srcdir && pwd`
-OBJROOT=`pwd`
-
-XTRA=false
-PA_SEARCH_LIBS_AND_ADD(xmalloc, iberty)
-PA_SEARCH_LIBS_AND_ADD(xstrdup, iberty)
-PA_SEARCH_LIBS_AND_ADD(bsd_signal, bsd, bsdsignal)
-PA_SEARCH_LIBS_AND_ADD(getopt_long, getopt, getopt_long)
-PA_SEARCH_LIBS_AND_ADD(getaddrinfo, [nsl resolv])
-if $pa_add_getaddrinfo
-then
-    AC_SEARCH_LIBS(gethostbyname, [nsl resolv],
-      [AC_SEARCH_LIBS(herror, [nsl resolv], ,
-	 [AC_MSG_ERROR(herror not found)])],
-      [AC_MSG_ERROR(gethostbyname not found)])
-else
-    AC_SEARCH_LIBS(freeaddrinfo, [nsl resolv], ,
-      [AC_MSG_ERROR(getaddrinfo but not freeaddrinfo found)])
-    AC_SEARCH_LIBS(gai_strerror, [nsl resolv], ,
-      [AC_MSG_ERROR(getaddrinfo but not gai_strerror found)])
-fi
-
-PA_SEARCH_LIBS_AND_ADD(inet_ntop, [nsl resolv])
-if $pa_add_inet_ntop
-then
-    AC_SEARCH_LIBS(inet_ntoa, [nsl resolv], ,
-      [AC_MSG_ERROR(inet_ntoa not found)])
-fi
-AC_SEARCH_LIBS(inet_aton, [nsl resolv], ,[AC_MSG_ERROR(inet_aton not found)])
-
-AC_CHECK_FUNCS(daemon, , [XTRA=true; AC_LIBOBJ(daemon)])
-AC_CHECK_FUNCS(dup2, , [XTRA=true; AC_LIBOBJ(dup2)])
-if $XTRA
-then
-  XTRALIBS="$OBJROOT/lib/libxtra.a $XTRALIBS"
-fi
-
-dnl
-dnl These libraries apply to the server only
-dnl
-
-common_libs="$LIBS"
-
-PA_HEADER_DEFINES(netinet/in.h, int, IPPORT_TFTP)
-
-PA_WITH_BOOL(tcpwrappers, 1,
-[  --without-tcpwrappers   disable tcpwrapper permissions checking],
-[
-	AC_SEARCH_LIBS(yp_get_default_domain, [nsl resolv])
-	PA_HAVE_TCPWRAPPERS
-],:)
-
-
-AH_TEMPLATE([WITH_REGEX],
-[Define if we are compiling with regex filename remapping.])
-
-PA_WITH_BOOL(remap, 1,
-[  --without-remap         disable regex-based filename remapping],
-[
-	AC_CHECK_HEADER(regex.h,
-	[
-		AC_SEARCH_LIBS(regcomp, [regex rx],
-		[
-			AC_DEFINE(WITH_REGEX)
-			TFTPDOBJS="remap.${OBJEXT} $TFTPDOBJS"
-		])
-	])
-],:)
-
-TFTPD_LIBS="$LIBS $XTRALIBS"
-LIBS="$common_libs"
-
-dnl
-dnl These libraries apply to the client only
-dnl
-
-AH_TEMPLATE([WITH_READLINE],
-[Define if we are compiling with readline/editline command-line editing.])
-
-PA_WITH_BOOL(readline, 1,
-[  --without-readline      disable the use of readline command-line editing],
-[
-	AC_CHECK_HEADER(readline/readline.h,
-	[
-		dnl readline may need libtermcap or somesuch...
-		AC_SEARCH_LIBS(tputs, [termcap terminfo])
-
-		AC_SEARCH_LIBS(readline, [readline history],
-		[AC_DEFINE(WITH_READLINE)])
-		AC_CHECK_HEADERS(readline/history.h)
-	],
-	[AC_CHECK_HEADER(editline/readline.h,
-	[
-		dnl editline may need libtermcap or somesuch...
-		AC_SEARCH_LIBS(tputs, [termcap terminfo])
-
-		AC_SEARCH_LIBS(editline, [edit],
-		[AC_DEFINE(WITH_READLINE)])
-	])])
-],:)
-
-TFTP_LIBS="$LIBS $XTRALIBS"
-LIBS="$common_libs"
-
-dnl
-dnl   Check for IPV6 and disable-ipv6
-dnl
-PA_STRUCT_SOCKADDR_IN6
-AC_MSG_CHECKING([for IPv6 support])
-PA_WITH_BOOL(ipv6, 1,
-[  --without-ipv6      disable the support for IPv6],
-[
-    if  $HAVE_INET6
-    then
-	AC_MSG_RESULT(yes)
-        AC_DEFINE(HAVE_IPV6, 1, [Define if IPv6 support is enabled.])
-        PA_STRUCT_IN6_PKTINFO
-    else
-	AC_MSG_RESULT(no)
-        AC_MSG_WARN([*** we do not have required IPv6 structs - IPv6 will be disabled])
-    fi
-],
-[AC_MSG_RESULT(disabled)])
-
-
-AC_SUBST(SRCROOT)
-AC_SUBST(OBJROOT)
-
-AC_SUBST(TFTP_LIBS)
-AC_SUBST(TFTPD_LIBS)
-AC_SUBST(TFTPDOBJS)
-
-AC_PROG_LN_S
-AC_PROG_RANLIB
-
-dnl
-dnl Make sure the install program has an absolute path if it
-dnl has a path at all.  autoconf doesn't do this "in order
-dnl to not pollute the cache."  Sigh.
-dnl Note: the $ needs to be double-quoted for reasons unknown.
-dnl
-AC_PROG_INSTALL
-[if echo "$INSTALL" | grep '^[^/].*/' > /dev/null 2>&1; then
-   INSTALL='\${SRCROOT}'/"$INSTALL"
-fi]
-
-AC_CONFIG_HEADERS(aconfig.h)
-AC_OUTPUT(MCONFIG)
diff --git a/lib/Makefile b/lib/Makefile
index a43ce19..a7fd057 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -4,7 +4,7 @@
 
 SRCROOT = ..
 
--include ../MCONFIG
+-include ../config/MCONFIG
 include ../MRULES
 
 ifeq ($(LIBOBJS),)
@@ -25,5 +25,3 @@ libxtra.a: $(LIBOBJS)
 	-rm -f libxtra.a
 	$(AR) libxtra.a $(LIBOBJS)
 	$(RANLIB) libxtra.a
-
-
diff --git a/lib/bsdsignal.c b/lib/bsdsignal.c
deleted file mode 100644
index 0aae136..0000000
--- a/lib/bsdsignal.c
+++ /dev/null
@@ -1,27 +0,0 @@
-/*
- * bsdsignal.c
- *
- * Use sigaction() to simulate BSD signal()
- */
-
-#include "config.h"
-
-void (*bsd_signal(int signum, void (*handler) (int))) (int) {
-    struct sigaction action, oldaction;
-
-    memset(&action, 0, sizeof action);
-    action.sa_handler = handler;
-    sigemptyset(&action.sa_mask);
-    sigaddset(&action.sa_mask, signum);
-    action.sa_flags = SA_RESTART;
-
-    if (sigaction(signum, &action, &oldaction) == -1) {
-#ifdef SIG_ERR
-        return SIG_ERR;
-#else
-        return NULL;
-#endif
-    }
-
-    return oldaction.sa_handler;
-}
diff --git a/tftp/Makefile b/tftp/Makefile
index 20f4c18..9faa62f 100644
--- a/tftp/Makefile
+++ b/tftp/Makefile
@@ -1,7 +1,7 @@
 SRCROOT = ..
 VERSION = $(shell cat ../version)
 
--include ../MCONFIG
+-include ../config/MCONFIG
 include ../MRULES
 
 OBJS = tftp.$(O) main.$(O)
diff --git a/tftp/extern.h b/tftp/extern.h
index 78474fc..9c578e6 100644
--- a/tftp/extern.h
+++ b/tftp/extern.h
@@ -31,10 +31,13 @@
  * SUCH DAMAGE.
  */
 
-#ifndef RECVFILE_H
-#define RECVFILE_H
+#ifndef EXTERN_H
+#define EXTERN_H
+
+#include "config.h"
 
 void tftp_recvfile(int, const char *, const char *);
 void tftp_sendfile(int, const char *, const char *);
+extern sigjmp_buf toplevel;
 
 #endif
diff --git a/tftp/main.c b/tftp/main.c
index 1b8a881..ac06330 100644
--- a/tftp/main.c
+++ b/tftp/main.c
@@ -188,7 +188,7 @@ char *xstrdup(const char *);
 
 const char *program;
 
-static inline void usage(int errcode)
+static void usage(int errcode)
 {
     fprintf(stderr,
 #ifdef HAVE_IPV6
@@ -305,7 +305,7 @@ int main(int argc, char *argv[])
         sp->s_proto = (char *)"udp";
     }
 
-    bsd_signal(SIGINT, intr);
+    tftp_signal(SIGINT, intr, 0);
 
     if (peerargc) {
         /* Set peer */
@@ -768,8 +768,8 @@ void intr(int sig)
 {
     (void)sig;                  /* Quiet unused warning */
 
-    bsd_signal(SIGALRM, SIG_IGN);
     alarm(0);
+    tftp_signal(SIGALRM, SIG_DFL, 0);
     siglongjmp(toplevel, -1);
 }
 
diff --git a/tftp/tftp.c b/tftp/tftp.c
index d15da22..33a4175 100644
--- a/tftp/tftp.c
+++ b/tftp/tftp.c
@@ -48,8 +48,7 @@ extern int maxtimeout;
 #define PKTSIZE    SEGSIZE+4
 char ackbuf[PKTSIZE];
 int timeout;
-sigjmp_buf toplevel;
-sigjmp_buf timeoutbuf;
+static sigjmp_buf timeoutbuf;
 
 static void nak(int, const char *);
 static int makerequest(int, const char *, struct tftphdr *, const char *);
@@ -85,7 +84,7 @@ void tftp_sendfile(int fd, const char *name, const char *mode)
     is_request = 1;             /* First packet is the actual WRQ */
     amount = 0;
 
-    bsd_signal(SIGALRM, timer);
+    tftp_signal(SIGALRM, timer, 0);
     do {
         if (is_request) {
             size = makerequest(WRQ, name, dp, mode) - 4;
@@ -191,7 +190,7 @@ void tftp_recvfile(int fd, const char *name, const char *mode)
     firsttrip = 1;
     amount = 0;
 
-    bsd_signal(SIGALRM, timer);
+    tftp_signal(SIGALRM, timer, 0);
     do {
         if (firsttrip) {
             size = makerequest(RRQ, name, ap, mode);
diff --git a/tftpd/Makefile b/tftpd/Makefile
index a05335d..5963581 100644
--- a/tftpd/Makefile
+++ b/tftpd/Makefile
@@ -1,7 +1,7 @@
 SRCROOT = ..
 VERSION = $(shell cat ../version)
 
--include ../MCONFIG
+-include ../config/MCONFIG
 include ../MRULES
 
 OBJS = tftpd.$(O) recvfrom.$(O) misc.$(O) $(TFTPDOBJS)
diff --git a/tftpd/misc.c b/tftpd/misc.c
index 07684dd..9070f96 100644
--- a/tftpd/misc.c
+++ b/tftpd/misc.c
@@ -19,19 +19,11 @@
 #include "tftpd.h"
 
 /*
- * Set the signal handler and flags.  Basically a user-friendly
- * wrapper around sigaction().
+ * Set the signal handler and flags, and error out on failure.
  */
-void set_signal(int signum, void (*handler) (int), int flags)
+void set_signal(int signum, sighandler_t handler, int flags)
 {
-    struct sigaction sa;
-
-    memset(&sa, 0, sizeof sa);
-    sa.sa_handler = handler;
-    sigemptyset(&sa.sa_mask);
-    sa.sa_flags = flags;
-
-    if (sigaction(signum, &sa, NULL)) {
+    if (tftp_signal(signum, handler, flags)) {
         syslog(LOG_ERR, "sigaction: %m");
         exit(EX_OSERR);
     }
diff --git a/tftpd/recvfrom.c b/tftpd/recvfrom.c
index 3ee5642..320678d 100644
--- a/tftpd/recvfrom.c
+++ b/tftpd/recvfrom.c
@@ -26,10 +26,12 @@
 
 #if defined(HAVE_RECVMSG) && defined(HAVE_MSGHDR_MSG_CONTROL)
 
-#include <sys/uio.h>
+#ifdef HAVE_SYS_UIO_H
+# include <sys/uio.h>
+#endif
 
 #ifdef IP_PKTINFO
-# ifndef HAVE_STRUCT_IN_PKTINFO
+# ifndef HAVE_STRUCT_IN_PKTINFO_IPI_ADDR
 #  ifdef __linux__
 /* Assume this version of glibc simply lacks the definition */
 struct in_pktinfo {
@@ -51,52 +53,59 @@ struct in_pktinfo {
 #endif
 
 /*
- * Check to see if this is a valid local address.  If so, we should
- * end up having the same local and remote address when trying to
- * bind to it.
+ * Check to see if this is a valid local address, meaning that we can
+ * legally bind to it.
  */
 static int address_is_local(const union sock_addr *addr)
 {
-    union sock_addr sa;
+    union sock_addr sa1, sa2;
     int sockfd = -1;
     int e;
     int rv = 0;
     socklen_t addrlen;
 
+    memcpy(&sa1, addr, sizeof sa1);
+
     /* Multicast or universal broadcast address? */
-    if (addr->sa.sa_family == AF_INET) {
-        if (ntohl(addr->si.sin_addr.s_addr) >= (224UL << 24))
+    if (sa1.sa.sa_family == AF_INET) {
+        if (ntohl(sa1.si.sin_addr.s_addr) >= (224UL << 24))
             return 0;
+	sa1.si.sin_port = 0;	/* Any port */
     }
 #ifdef HAVE_IPV6
-    else if (addr->sa.sa_family == AF_INET6) {
-        if (IN6_IS_ADDR_MULTICAST(&addr->s6.sin6_addr))
+    else if (sa1.sa.sa_family == AF_INET6) {
+        if (IN6_IS_ADDR_MULTICAST(&sa1.s6.sin6_addr))
             return 0;
+	sa1.s6.sin6_port = 0;	/* Any port */
     }
 #endif
     else
         return 0;
 
-    sockfd = socket(addr->sa.sa_family, SOCK_DGRAM, 0);
+    sockfd = socket(sa1.sa.sa_family, SOCK_DGRAM, 0);
     if (sockfd < 0)
         goto err;
 
-    if (connect(sockfd, &addr->sa, SOCKLEN(addr)))
+    if (bind(sockfd, &sa1.sa, SOCKLEN(&sa1)))
         goto err;
 
     addrlen = SOCKLEN(addr);
-    if (getsockname(sockfd, (struct sockaddr *)&sa, &addrlen))
+    if (getsockname(sockfd, (struct sockaddr *)&sa2, &addrlen))
         goto err;
 
-    if (addr->sa.sa_family == AF_INET)
-        rv = sa.si.sin_addr.s_addr == addr->si.sin_addr.s_addr;
+    if (sa1.sa.sa_family != sa2.sa.sa_family)
+	goto err;
+
+    if (sa2.sa.sa_family == AF_INET)
+        rv = sa1.si.sin_addr.s_addr == sa2.si.sin_addr.s_addr;
 #ifdef HAVE_IPV6
-    else if (addr->sa.sa_family == AF_INET6)
-        rv = IN6_ARE_ADDR_EQUAL(&sa.s6.sin6_addr, &addr->s6.sin6_addr);
+    else if (sa2.sa.sa_family == AF_INET6)
+        rv = IN6_ARE_ADDR_EQUAL(&sa1.s6.sin6_addr, &sa2.s6.sin6_addr);
 #endif
     else
         rv = 0;
-  err:
+
+err:
     e = errno;
 
     if (sockfd >= 0)
@@ -106,10 +115,31 @@ static int address_is_local(const union sock_addr *addr)
     return rv;
 }
 
+static void normalize_ip6_compat(union sock_addr *myaddr)
+{
+#ifdef HAVE_IPV6
+    static const uint8_t ip6_compat_prefix[12] =
+	{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xff, 0xff };
+    struct sockaddr_in in;
+
+    if (myaddr->sa.sa_family == AF_INET6 &&
+	!memcmp(&myaddr->s6.sin6_addr, ip6_compat_prefix,
+		sizeof ip6_compat_prefix)) {
+	bzero(&in, sizeof in);
+	in.sin_family = AF_INET;
+	in.sin_port = myaddr->s6.sin6_port;
+	memcpy(&in.sin_addr, (const char *)&myaddr->s6.sin6_addr +
+	       sizeof ip6_compat_prefix, sizeof in.sin_addr);
+	memcpy(&myaddr->si, &in, sizeof in);
+    }
+#else
+    (void)myaddr;
+#endif
+}
+
 int
 myrecvfrom(int s, void *buf, int len, unsigned int flags,
-           struct sockaddr *from, socklen_t * fromlen,
-           union sock_addr *myaddr)
+           union sock_addr *from, union sock_addr *myaddr)
 {
     struct msghdr msg;
     struct iovec iov;
@@ -142,16 +172,16 @@ myrecvfrom(int s, void *buf, int len, unsigned int flags,
 
     /* Try to enable getting the return address */
 #ifdef IP_RECVDSTADDR
-    if (from->sa_family == AF_INET)
+    if (from->sa.sa_family == AF_INET)
         setsockopt(s, IPPROTO_IP, IP_RECVDSTADDR, &on, sizeof(on));
 #endif
 #ifdef IP_PKTINFO
-    if (from->sa_family == AF_INET)
+    if (from->sa.sa_family == AF_INET)
         setsockopt(s, IPPROTO_IP, IP_PKTINFO, &on, sizeof(on));
 #endif
 #ifdef HAVE_IPV6
 #ifdef IPV6_RECVPKTINFO
-    if (from->sa_family == AF_INET6)
+    if (from->sa.sa_family == AF_INET6)
         setsockopt(s, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, sizeof(on));
 #endif
 #endif
@@ -160,8 +190,8 @@ myrecvfrom(int s, void *buf, int len, unsigned int flags,
     msg.msg_controllen = sizeof(control_un);
     msg.msg_flags = 0;
 
-    msg.msg_name = from;
-    msg.msg_namelen = *fromlen;
+    msg.msg_name = &from->sa;
+    msg.msg_namelen = sizeof(*from);
     iov.iov_base = buf;
     iov.iov_len = len;
     msg.msg_iov = &iov;
@@ -170,11 +200,9 @@ myrecvfrom(int s, void *buf, int len, unsigned int flags,
     if ((n = recvmsg(s, &msg, flags)) < 0)
         return n;               /* Error */
 
-    *fromlen = msg.msg_namelen;
-
     if (myaddr) {
         bzero(myaddr, sizeof(*myaddr));
-        myaddr->sa.sa_family = from->sa_family;
+        myaddr->sa.sa_family = from->sa.sa_family;
 
         if (msg.msg_controllen < sizeof(struct cmsghdr) ||
             (msg.msg_flags & MSG_CTRUNC))
@@ -183,7 +211,7 @@ myrecvfrom(int s, void *buf, int len, unsigned int flags,
         for (cmptr = CMSG_FIRSTHDR(&msg); cmptr != NULL;
              cmptr = CMSG_NXTHDR(&msg, cmptr)) {
 
-            if (from->sa_family == AF_INET) {
+            if (from->sa.sa_family == AF_INET) {
                 myaddr->sa.sa_family = AF_INET;
 #ifdef IP_RECVDSTADDR
                 if (cmptr->cmsg_level == IPPROTO_IP &&
@@ -204,7 +232,7 @@ myrecvfrom(int s, void *buf, int len, unsigned int flags,
 #endif
             }
 #ifdef HAVE_IPV6
-            else if (from->sa_family == AF_INET6) {
+            else if (from->sa.sa_family == AF_INET6) {
                 myaddr->sa.sa_family = AF_INET6;
 #ifdef IP6_RECVDSTADDR
                 if (cmptr->cmsg_level == IPPROTO_IPV6 &&
@@ -215,17 +243,23 @@ myrecvfrom(int s, void *buf, int len, unsigned int flags,
 
 #ifdef HAVE_STRUCT_IN6_PKTINFO
                 if (cmptr->cmsg_level == IPPROTO_IPV6 &&
-                    (cmptr->cmsg_type == IPV6_RECVPKTINFO ||
+		    (
+#ifdef IPV6_RECVPKTINFO
+		     cmptr->cmsg_type == IPV6_RECVPKTINFO ||
+#endif
                      cmptr->cmsg_type == IPV6_PKTINFO)) {
-                    memcpy(&pktinfo6, CMSG_DATA(cmptr),
-                           sizeof(struct in6_pktinfo));
-                    memcpy(&myaddr->s6.sin6_addr, &pktinfo6.ipi6_addr,
-                           sizeof(struct in6_addr));
+		    memcpy(&pktinfo6, CMSG_DATA(cmptr),
+			   sizeof(struct in6_pktinfo));
+		    memcpy(&myaddr->s6.sin6_addr, &pktinfo6.ipi6_addr,
+			   sizeof(struct in6_addr));
                 }
 #endif
             }
 #endif
         }
+
+	normalize_ip6_compat(myaddr);
+
         /* If the address is not a valid local address,
          * then bind to any address...
          */
@@ -238,6 +272,9 @@ myrecvfrom(int s, void *buf, int len, unsigned int flags,
 #endif
         }
     }
+
+    normalize_ip6_compat(from);
+
     return n;
 }
 
@@ -245,16 +282,16 @@ myrecvfrom(int s, void *buf, int len, unsigned int flags,
 
 int
 myrecvfrom(int s, void *buf, int len, unsigned int flags,
-           struct sockaddr *from, socklen_t * fromlen,
-           union sock_addr *myaddr)
+           union sock_addr *from, union sock_addr *myaddr)
 {
     /* There is no way we can get the local address, fudge it */
+    socklen_t fromlen = sizeof(*from);
 
     bzero(myaddr, sizeof(*myaddr));
-    myaddr->sa.sa_family = from->sa_family;
+    myaddr->sa.sa_family = from->sa.sa_family;
     sa_set_port(myaddr, htons(IPPORT_TFTP));
 
-    return recvfrom(s, buf, len, flags, from, fromlen);
+    return recvfrom(s, buf, len, flags, &from->sa, &fromlen);
 }
 
 #endif
diff --git a/tftpd/recvfrom.h b/tftpd/recvfrom.h
index e3c4055..7773a0d 100644
--- a/tftpd/recvfrom.h
+++ b/tftpd/recvfrom.h
@@ -19,5 +19,4 @@
 
 int
 myrecvfrom(int s, void *buf, int len, unsigned int flags,
-           struct sockaddr *from, socklen_t *fromlen,
-           union sock_addr *myaddr);
+           union sock_addr *from, union sock_addr *myaddr);
diff --git a/tftpd/remap.c b/tftpd/remap.c
index 1e7abe7..413d117 100644
--- a/tftpd/remap.c
+++ b/tftpd/remap.c
@@ -1,6 +1,6 @@
 /* ----------------------------------------------------------------------- *
  *
- *   Copyright 2001-2007 H. Peter Anvin - All Rights Reserved
+ *   Copyright 2001-2024 H. Peter Anvin - All Rights Reserved
  *
  *   This program is free software available under the same license
  *   as the "OpenBSD" operating system, distributed at
@@ -22,7 +22,7 @@
 #include "tftpd.h"
 #include "remap.h"
 
-#define DEADMAN_MAX_STEPS	1024    /* Timeout after this many steps */
+#define DEADMAN_MAX_STEPS	4096    /* Timeout after this many steps */
 #define MAXLINE			16384   /* Truncate a line at this many bytes */
 
 #define RULE_REWRITE	0x01    /* This is a rewrite rule */
@@ -31,12 +31,20 @@
 #define RULE_RESTART	0x08    /* Restart at the top after matching this rule */
 #define RULE_ABORT	0x10    /* Terminate processing with an error */
 #define RULE_INVERSE	0x20    /* Execute if regex *doesn't* match */
+#define RULE_IPV4	0x40	/* IPv4 only */
+#define RULE_IPV6	0x80	/* IPv6 only */
+
+#define RULE_HASFILE	0x100	/* Valid if rule results in a valid filename */
+#define RULE_RRQ	0x200	/* Get (read) only */
+#define RULE_WRQ	0x400	/* Put (write) only */
+#define RULE_SEDG	0x800   /* sed-style global */
+
+int deadman_max_steps = DEADMAN_MAX_STEPS;
 
 struct rule {
     struct rule *next;
     int nrule;
-    int rule_flags;
-    char rule_mode;
+    unsigned int rule_flags;
     regex_t rx;
     const char *pattern;
 };
@@ -56,22 +64,30 @@ static int xform_tolower(int c)
     return tolower(c);
 }
 
-/* Do \-substitution.  Call with string == NULL to get length only. */
-static int genmatchstring(char *string, const char *pattern,
-                          const char *input, const regmatch_t * pmatch,
-                          match_pattern_callback macrosub)
+/*
+ * Do \-substitution.  Call with string == NULL to get length only.
+ * "start" indicates an offset into the input buffer where the pattern
+ * match was started.
+ */
+static int do_genmatchstring(char *string, const char *pattern,
+                             const char *ibuf,
+                             const regmatch_t * pmatch,
+                             match_pattern_callback macrosub,
+                             int start, int *nextp)
 {
     int (*xform) (int) = xform_null;
     int len = 0;
     int n, mlen, sublen;
     int endbytes;
+    const char *input = ibuf + start;
 
     /* Get section before match; note pmatch[0] is the whole match */
     endbytes = strlen(input) - pmatch[0].rm_eo;
-    len = pmatch[0].rm_so + endbytes;
+    len = start + pmatch[0].rm_so;
     if (string) {
-        memcpy(string, input, pmatch[0].rm_so);
-        string += pmatch[0].rm_so;
+        /* Copy the prefix before "start" as well! */
+        memcpy(string, ibuf, start + pmatch[0].rm_so);
+        string += start + pmatch[0].rm_so;
     }
 
     /* Transform matched section */
@@ -97,7 +113,7 @@ static int genmatchstring(char *string, const char *pattern,
                     mlen = pmatch[n].rm_eo - pmatch[n].rm_so;
                     len += mlen;
                     if (string) {
-                        const char *p = input + pmatch[n].rm_so;
+                        const char *p = input + start + pmatch[n].rm_so;
                         while (mlen--)
                             *string++ = xform(*p++);
                     }
@@ -140,7 +156,12 @@ static int genmatchstring(char *string, const char *pattern,
         }
     }
 
+    /* Pointer to post-substitution tail */
+    if (nextp)
+        *nextp = len;
+
     /* Copy section after match */
+    len += endbytes;
     if (string) {
         memcpy(string, input + pmatch[0].rm_eo, endbytes);
         string[endbytes] = '\0';
@@ -149,6 +170,26 @@ static int genmatchstring(char *string, const char *pattern,
     return len;
 }
 
+/*
+ * Ditto, but allocate the string in a new buffer
+ */
+
+static int genmatchstring(char **string, const char *pattern,
+                          const char *ibuf,
+                          const regmatch_t * pmatch,
+                          match_pattern_callback macrosub,
+                          int start, int *nextp)
+{
+    int len;
+    char *buf;
+
+    len = do_genmatchstring(NULL, pattern, ibuf, pmatch,
+                            macrosub, start, NULL);
+    *string = buf = tfmalloc(len + 1);
+    return do_genmatchstring(buf, pattern, ibuf, pmatch,
+                             macrosub, start, nextp);
+}
+
 /*
  * Extract a string terminated by non-escaped whitespace; ignoring
  * leading whitespace.  Consider an unescaped # to be a comment marker,
@@ -206,11 +247,17 @@ static int parseline(char *line, struct rule *r, int lineno)
             r->rule_flags |= RULE_REWRITE;
             break;
         case 'g':
-            r->rule_flags |= RULE_GLOBAL;
+            if (r->rule_flags & RULE_GLOBAL)
+                r->rule_flags |= RULE_SEDG;
+            else
+                r->rule_flags |= RULE_GLOBAL;
             break;
         case 'e':
             r->rule_flags |= RULE_EXIT;
             break;
+        case 'E':
+            r->rule_flags |= RULE_HASFILE;
+            break;
         case 's':
             r->rule_flags |= RULE_RESTART;
             break;
@@ -223,9 +270,17 @@ static int parseline(char *line, struct rule *r, int lineno)
         case '~':
             r->rule_flags |= RULE_INVERSE;
             break;
-	case 'G':
-	case 'P':
-            r->rule_mode = *p;
+        case '4':
+            r->rule_flags |= RULE_IPV4;
+            break;
+        case '6':
+            r->rule_flags |= RULE_IPV6;
+            break;
+        case 'G':
+            r->rule_flags |= RULE_RRQ;
+            break;
+        case 'P':
+            r->rule_flags |= RULE_WRQ;
             break;
         default:
             syslog(LOG_ERR,
@@ -236,15 +291,21 @@ static int parseline(char *line, struct rule *r, int lineno)
         }
     }
 
-    /* RULE_GLOBAL only applies when RULE_REWRITE specified */
-    if (!(r->rule_flags & RULE_REWRITE))
-        r->rule_flags &= ~RULE_GLOBAL;
-
-    if ((r->rule_flags & (RULE_INVERSE | RULE_REWRITE)) ==
-        (RULE_INVERSE | RULE_REWRITE)) {
-        syslog(LOG_ERR, "r rules cannot be inverted, line %d: %s\n",
-               lineno, line);
-        return -1;              /* Error */
+    if (r->rule_flags & RULE_REWRITE) {
+        if (r->rule_flags & RULE_INVERSE) {
+            syslog(LOG_ERR, "r rules cannot be inverted, line %d: %s\n",
+                   lineno, line);
+            return -1;              /* Error */
+        }
+        if ((r->rule_flags & (RULE_GLOBAL|RULE_SEDG|RULE_HASFILE))
+            == (RULE_GLOBAL|RULE_HASFILE)) {
+            syslog(LOG_ERR, "E rules cannot be combined with g (but gg is OK), line %d: %s\n",
+                   lineno, line);
+            return -1;              /* Error */
+        }
+    } else {
+        /* RULE_GLOBAL and RULE_SEDG are meaningless without RULE_REWRITE */
+        r->rule_flags &= ~(RULE_GLOBAL|RULE_SEDG);
     }
 
     /* Read and compile the regex */
@@ -325,17 +386,24 @@ void freerules(struct rule *r)
 }
 
 /* Execute a rule set on a string; returns a malloc'd new string. */
-char *rewrite_string(const char *input, const struct rule *rules,
-                     char mode, match_pattern_callback macrosub,
+char *rewrite_string(const struct formats *pf,
+                     const char *input, const struct rule *rules,
+                     int mode, int af, match_pattern_callback macrosub,
                      const char **errmsg)
 {
     char *current = tfstrdup(input);
-    char *newstr;
+    char *newstr, *newerstr;
+    const char *accerr;
     const struct rule *ruleptr = rules;
     regmatch_t pmatch[10];
+    int i;
     int len;
     int was_match = 0;
-    int deadman = DEADMAN_MAX_STEPS;
+    int deadman = deadman_max_steps;
+    int matchsense;
+    int pmatches;
+    unsigned int bad_flags;
+    int ggoffset;
 
     /* Default error */
     *errmsg = "Remap table failure";
@@ -344,86 +412,121 @@ char *rewrite_string(const char *input, const struct rule *rules,
         syslog(LOG_INFO, "remap: input: %s", current);
     }
 
-    for (ruleptr = rules; ruleptr; ruleptr = ruleptr->next) {
-	if (ruleptr->rule_mode && ruleptr->rule_mode != mode)
-            continue;           /* Rule not applicable, try next */
+    bad_flags = 0;
+    if (mode != RRQ)    bad_flags |= RULE_RRQ;
+    if (mode != WRQ)    bad_flags |= RULE_WRQ;
+    if (af != AF_INET)  bad_flags |= RULE_IPV4;
+    if (af != AF_INET6) bad_flags |= RULE_IPV6;
 
-        if (!deadman--) {
-            syslog(LOG_WARNING,
-                   "remap: Breaking loop, input = %s, last = %s", input,
-                   current);
-            free(current);
-            return NULL;        /* Did not terminate! */
-        }
+    for (ruleptr = rules; ruleptr; ruleptr = ruleptr->next) {
+        if (ruleptr->rule_flags & bad_flags)
+            continue;		/* This rule is excluded by flags */
+
+        matchsense = ruleptr->rule_flags & RULE_INVERSE ? REG_NOMATCH : 0;
+        pmatches = ruleptr->rule_flags & RULE_INVERSE ? 0 : 10;
+
+        /* Clear the pmatch[] array */
+        for (i = 0; i < 10; i++)
+            pmatch[i].rm_so = pmatch[i].rm_eo = -1;
+
+        was_match = 0;
 
         do {
-            if (regexec(&ruleptr->rx, current, 10, pmatch, 0) ==
-                (ruleptr->rule_flags & RULE_INVERSE ? REG_NOMATCH : 0)) {
-                /* Match on this rule */
-                was_match = 1;
+            if (!deadman--)
+                goto dead;
 
-                if (ruleptr->rule_flags & RULE_INVERSE) {
-                    /* No actual match, so clear out the pmatch array */
-                    int i;
-                    for (i = 0; i < 10; i++)
-                        pmatch[i].rm_so = pmatch[i].rm_eo = -1;
-                }
+            if (regexec(&ruleptr->rx, current, pmatches, pmatch, 0)
+                != matchsense)
+                break;          /* No match, break out of do loop */
 
-                if (ruleptr->rule_flags & RULE_ABORT) {
-                    if (verbosity >= 3) {
-                        syslog(LOG_INFO, "remap: rule %d: abort: %s",
-                               ruleptr->nrule, current);
-                    }
-                    if (ruleptr->pattern[0]) {
-                        /* Custom error message */
-                        len =
-                            genmatchstring(NULL, ruleptr->pattern, current,
-                                           pmatch, macrosub);
-                        newstr = tfmalloc(len + 1);
-                        genmatchstring(newstr, ruleptr->pattern, current,
-                                       pmatch, macrosub);
-                        *errmsg = newstr;
-                    } else {
-                        *errmsg = NULL;
-                    }
-                    free(current);
-                    return (NULL);
-                }
+            /* Match on this rule */
+            was_match = 1;
 
-                if (ruleptr->rule_flags & RULE_REWRITE) {
-                    len = genmatchstring(NULL, ruleptr->pattern, current,
-                                         pmatch, macrosub);
-                    newstr = tfmalloc(len + 1);
-                    genmatchstring(newstr, ruleptr->pattern, current,
-                                   pmatch, macrosub);
-                    free(current);
-                    current = newstr;
-                    if (verbosity >= 3) {
-                        syslog(LOG_INFO, "remap: rule %d: rewrite: %s",
-                               ruleptr->nrule, current);
-                    }
+            if (ruleptr->rule_flags & RULE_ABORT) {
+                if (verbosity >= 3) {
+                    syslog(LOG_INFO, "remap: rule %d: abort: %s",
+                           ruleptr->nrule, current);
                 }
-            } else {
-                break;          /* No match, terminate unconditionally */
+                if (ruleptr->pattern[0]) {
+                    /* Custom error message */
+                    genmatchstring(&newstr, ruleptr->pattern, current,
+                                   pmatch, macrosub, 0, NULL);
+                    *errmsg = newstr;
+                } else {
+                    *errmsg = NULL;
+                }
+                free(current);
+                return (NULL);
             }
-            /* If the rule is global, keep going until no match */
-        } while (ruleptr->rule_flags & RULE_GLOBAL);
 
-        if (was_match) {
-            was_match = 0;
+            if (ruleptr->rule_flags & RULE_REWRITE) {
+                len = genmatchstring(&newstr, ruleptr->pattern, current,
+                                     pmatch, macrosub, 0, &ggoffset);
 
-            if (ruleptr->rule_flags & RULE_EXIT) {
-                if (verbosity >= 3) {
-                    syslog(LOG_INFO, "remap: rule %d: exit",
-                           ruleptr->nrule);
+                if (ruleptr->rule_flags & RULE_SEDG) {
+                    /* sed-style partial-matching global */
+                    while (ggoffset < len &&
+                           regexec(&ruleptr->rx, newstr + ggoffset,
+                                   pmatches, pmatch,
+                                   ggoffset ? REG_NOTBOL : 0)
+                           == matchsense) {
+                        if (!deadman--) {
+                            free(current);
+                            current = newstr;
+                            goto dead;
+                        }
+                        len = genmatchstring(&newerstr, ruleptr->pattern,
+                                             newstr, pmatch, macrosub,
+                                             ggoffset, &ggoffset);
+                        free(newstr);
+                        newstr = newerstr;
+                    }
                 }
-                return current; /* Exit here, we're done */
-            } else if (ruleptr->rule_flags & RULE_RESTART) {
-                ruleptr = rules;        /* Start from the top */
-                if (verbosity >= 3) {
-                    syslog(LOG_INFO, "remap: rule %d: restart",
-                           ruleptr->nrule);
+
+                if ((ruleptr->rule_flags & RULE_HASFILE) &&
+                    pf->f_validate(newstr, mode, pf, &accerr)) {
+                    if (verbosity >= 3) {
+                        syslog(LOG_INFO, "remap: rule %d: ignored rewrite (%s): %s",
+                               ruleptr->nrule, accerr, newstr);
+                    }
+                    free(newstr);
+                    was_match = 0;
+                    break;
                 }
+
+                free(current);
+                current = newstr;
+                if (verbosity >= 3) {
+                    syslog(LOG_INFO, "remap: rule %d: rewrite: %s",
+                           ruleptr->nrule, current);
+                }
+            } else if (ruleptr->rule_flags & RULE_HASFILE) {
+                if (pf->f_validate(current, mode, pf, &accerr)) {
+                    if (verbosity >= 3) {
+                        syslog(LOG_INFO, "remap: rule %d: not exiting (%s)\n",
+                               ruleptr->nrule, accerr);
+                    }
+                    was_match = 0;
+                    break;
+                }
+            }
+            /* If the rule is (old-style) global, keep going until no match */
+        } while ((ruleptr->rule_flags & (RULE_GLOBAL|RULE_SEDG)) == RULE_GLOBAL);
+
+        if (!was_match)
+            continue;           /* Next rule */
+
+        if (ruleptr->rule_flags & (RULE_EXIT|RULE_HASFILE)) {
+            if (verbosity >= 3) {
+                syslog(LOG_INFO, "remap: rule %d: exit",
+                       ruleptr->nrule);
+            }
+            return current; /* Exit here, we're done */
+        } else if (ruleptr->rule_flags & RULE_RESTART) {
+            ruleptr = rules;        /* Start from the top */
+            if (verbosity >= 3) {
+                syslog(LOG_INFO, "remap: rule %d: restart",
+                       ruleptr->nrule);
             }
         }
     }
@@ -432,4 +535,11 @@ char *rewrite_string(const char *input, const struct rule *rules,
         syslog(LOG_INFO, "remap: done");
     }
     return current;
+
+dead:                           /* Deadman expired */
+    syslog(LOG_ERR,
+           "remap: Breaking loop after %d steps, input = %s, last = %s",
+           deadman_max_steps, input, current);
+    free(current);
+    return NULL;        /* Did not terminate! */
 }
diff --git a/tftpd/remap.h b/tftpd/remap.h
index 69ca08d..c8d76ff 100644
--- a/tftpd/remap.h
+++ b/tftpd/remap.h
@@ -35,8 +35,13 @@ struct rule *parserulefile(FILE *);
 void freerules(struct rule *);
 
 /* Execute a rule set on a string; returns a malloc'd new string. */
-char *rewrite_string(const char *, const struct rule *, char,
+struct formats;
+char *rewrite_string(const struct formats *, const char *,
+		     const struct rule *, int, int,
                      match_pattern_callback, const char **);
 
+/* Remapping deadman counter */
+extern int deadman_max_steps;
+
 #endif                          /* WITH_REGEX */
 #endif                          /* TFTPD_REMAP_H */
diff --git a/tftpd/tftpd.8.in b/tftpd/tftpd.8.in
index 78b4cfb..3d43325 100644
--- a/tftpd/tftpd.8.in
+++ b/tftpd/tftpd.8.in
@@ -1,5 +1,5 @@
 .\" -*- nroff -*- --------------------------------------------------------- *
-.\"  
+.\"
 .\" Copyright (c) 1990, 1993, 1994
 .\"     The Regents of the University of California.  All rights reserved.
 .\"
@@ -30,7 +30,7 @@
 .\" SUCH DAMAGE.
 .\"
 .\"----------------------------------------------------------------------- */
-.TH TFTPD 8 "14 September 2009" "tftp-hpa @@VERSION@@" "System Manager's Manual"
+.TH TFTPD 8 "7 June 2014" "tftp-hpa @@VERSION@@" "System Manager's Manual"
 .SH NAME
 .B tftpd
 \- Trivial File Transfer Protocol server
@@ -155,7 +155,7 @@ or
 .B utimeout
 option is negotiated.  The default is 1000000 (1 second.)
 .TP
-\fB\-\-mapfile\fP \fIremap-file\fP, \fB\-m\fP \fIremap-file\fP
+\fB\-\-map-file\fP \fIremap-file\fP, \fB\-m\fP \fIremap-file\fP
 Specify the use of filename remapping.  The
 .I remap-file
 is a file containing the remapping rules.  See the section on filename
@@ -163,6 +163,10 @@ remapping below.  This option may not be compiled in, see the output of
 .B "in.tftpd \-V"
 to verify whether or not it is available.
 .TP
+.\fB\-\-map-steps\fP \fIsteps\fP
+Specify the number of remapping rules that may be executed before the
+filename mapping fails. The default is 4096.
+.TP
 \fB\-\-verbose\fP, \fB\-v\fP
 Increase the logging verbosity of
 .BR tftpd .
@@ -238,7 +242,7 @@ option, but crash with an error if they actually get the option
 accepted by the server.
 .SH "FILENAME REMAPPING"
 The
-.B \-\-mapfile
+.B \-\-map-file
 option specifies a file which contains filename remapping rules.  Each
 non-comment line (comments begin with hash marks,
 .BR # )
@@ -270,7 +274,18 @@ by the
 The replacement pattern may contain escape sequences; see below.
 .TP
 .B g
-Repeat this rule until it no longer matches.  This is always used with
+Repeat this rule until it no longer matches. This is always used with
+.BR r .
+.TP
+.B gg
+Repeat this rule until it no longer matches, but only on the portion
+of the string that has not yet been matched, similar to how the
+.B s
+command with the
+.B g
+option works in
+.BR sed (1).
+This is always used with
 .BR r .
 .TP
 .B i
@@ -281,6 +296,17 @@ case-insensitively.  By default it is case sensitive.
 .B e
 If this rule matches, end rule processing after executing the rule.
 .TP
+.B E
+If this rule matches,
+\fIand the result matches a filename that can be transferred\fP,
+end rule processing after executing the rule. If this is combined with
+.BR r ,
+then if the substitution does \fInot\fP result in a valid filename,
+the substitution is undone. This cannot be combined with
+.BR g ,
+but \fIcan\fP be combined with
+.BR gg .
+.TP
 .B s
 If this rule matches, start rule processing over from the very first
 rule after executing this rule.
@@ -295,16 +321,22 @@ This rule applies to GET (RRQ) requests only.
 .B P
 This rule applies to PUT (WRQ) requests only.
 .TP
+.B 4
+This rule applies to IPv4 sessions only.
+.TP
+.B 6
+This rule applies to IPv6 sessions only.
+.TP
 .B ~
 Inverse the sense of this rule, i.e. execute the
 .I operation
 only if the
 .I regex
 .I doesn't
-match.  Cannot used together with 
+match.  Cannot used together with
 .BR r .
 .PP
-The following escape sequences are recognized as part of the
+The following escape sequences are recognized as part of a
 .IR "replacement pattern" :
 .TP
 \fB\\0\fP
@@ -318,12 +350,14 @@ subexpressions, \\( ... \\), of the
 pattern.
 .TP
 \fB\\i\fP
-The IP address of the requesting host, in dotted-quad notation
-(e.g. 192.0.2.169).
+The IP address of the requesting host, in dotted-quad notation for
+IPv4 (e.g. 192.0.2.169) or conventional colon form for IPv6
+(e.g. 2001:db8::1).
 .TP
 \fB\\x\fP
-The IP address of the requesting host, in hexadecimal notation
-(e.g. C00002A9).
+The IP address of the requesting host, in expanded hexadecimal
+notation (e.g. C00002A9 for IPv4, or 20010DB8000000000000000000000001
+for IPv6).
 .TP
 \fB\\\\\fP
 Literal backslash.
@@ -383,14 +417,14 @@ Access to files can, and should, be restricted by invoking
 .B tftpd
 with a list of directories by including pathnames as server program
 arguments on the command line.  In this case access is restricted to
-files whole names are prefixed by one of the given directories.  If
+files whose names are prefixed by one of the given directories.  If
 possible, it is recommended that the
 .B \-\-secure
 flag is used to set up a chroot() environment for the server to run in
 once a connection has been set up.
 .PP
 Finally, the filename remapping
-.RB ( \-\-mapfile
+.RB ( \-\-map-file
 flag) support can be used to provide a limited amount of additional
 access control.
 .SH "CONFORMING TO"
diff --git a/tftpd/tftpd.c b/tftpd/tftpd.c
index 1873e70..e0041dc 100644
--- a/tftpd/tftpd.c
+++ b/tftpd/tftpd.c
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 1983 Regents of the University of California.
  * Copyright (c) 1999-2009 H. Peter Anvin
- * Copyright (c) 2011 Intel Corporation; author: H. Peter Anvin
+ * Copyright (c) 2011-2014 Intel Corporation; author: H. Peter Anvin
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -76,7 +76,7 @@ static int ai_fam = AF_INET;
 #define TRIES   6               /* Number of attempts to send each packet */
 #define TIMEOUT_LIMIT ((1 << TRIES)-1)
 
-const char *__progname;
+const char *tftpd_progname;
 static int peer;
 static unsigned long timeout  = TIMEOUT;        /* Current timeout value */
 static unsigned long rexmtval = TIMEOUT;       /* Basic timeout value */
@@ -93,7 +93,6 @@ static unsigned int max_blksize = MAX_SEGSIZE;
 static char tmpbuf[INET6_ADDRSTRLEN], *tmp_p;
 
 static union sock_addr from;
-static socklen_t fromlen;
 static off_t tsize;
 static int tsize_ok;
 
@@ -107,11 +106,12 @@ int portrange = 0;
 unsigned int portrange_from, portrange_to;
 int verbosity = 0;
 
-struct formats;
 #ifdef WITH_REGEX
 static struct rule *rewrite_rules = NULL;
 #endif
 
+static FILE *file;
+
 int tftp(struct tftphdr *, int);
 static void nak(int, const char *);
 static void timer(int);
@@ -153,7 +153,7 @@ static void handle_exit(int sig)
 }
 
 /* Handle timeout signal or timeout event */
-void timer(int sig)
+static void timer(int sig)
 {
     (void)sig;                  /* Suppress unused warning */
     timeout <<= 1;
@@ -163,14 +163,14 @@ void timer(int sig)
 }
 
 #ifdef WITH_REGEX
-static struct rule *read_remap_rules(const char *file)
+static struct rule *read_remap_rules(const char *rulefile)
 {
     FILE *f;
     struct rule *rulep;
 
-    f = fopen(file, "rt");
+    f = fopen(rulefile, "rt");
     if (!f) {
-        syslog(LOG_ERR, "Cannot open map file: %s: %m", file);
+        syslog(LOG_ERR, "Cannot open map file: %s: %m", rulefile);
         exit(EX_NOINPUT);
     }
     rulep = parserulefile(f);
@@ -185,7 +185,8 @@ static struct rule *read_remap_rules(const char *file)
  */
 static int lock_file(int fd, int lock_write)
 {
-#if defined(HAVE_FCNTL) && defined(HAVE_F_SETLK_DEFINITION)
+    (void)lock_write;
+#if defined(HAVE_FCNTL) && HAVE_DECL_F_SETLK
   struct flock fl;
 
   fl.l_type   = lock_write ? F_WRLCK : F_RDLCK;
@@ -193,7 +194,7 @@ static int lock_file(int fd, int lock_write)
   fl.l_start  = 0;
   fl.l_len    = 0;		/* Whole file */
   return fcntl(fd, F_SETLK, &fl);
-#elif defined(HAVE_LOCK_SH_DEFINITION)
+#elif defined(HAVE_FLOCK) && HAVE_DECL_LOCK_SH && HAVE_DECL_LOCK_EX
   return flock(fd, lock_write ? LOCK_EX|LOCK_NB : LOCK_SH|LOCK_NB);
 #else
   return 0;			/* Hope & pray... */
@@ -324,8 +325,9 @@ static int split_port(char **ap, char **pp)
 
 enum long_only_options {
     OPT_VERBOSITY	= 256,
+    OPT_MAP_STEPS
 };
-    
+
 static struct option long_options[] = {
     { "ipv4",        0, NULL, '4' },
     { "ipv6",        0, NULL, '6' },
@@ -346,6 +348,7 @@ static struct option long_options[] = {
     { "retransmit",  1, NULL, 'T' },
     { "port-range",  1, NULL, 'R' },
     { "map-file",    1, NULL, 'm' },
+    { "map-steps",   1, NULL, OPT_MAP_STEPS },
     { "pidfile",     1, NULL, 'P' },
     { NULL, 0, NULL, 0 }
 };
@@ -375,6 +378,7 @@ int main(int argc, char **argv)
     int spec_umask = 0;
     int c;
     int setrv;
+    int die;
     int waittime = 900;         /* Default time to wait for a connect */
     const char *user = "nobody";        /* Default user */
     char *p, *ep;
@@ -387,9 +391,9 @@ int main(int argc, char **argv)
     /* basename() is way too much of a pain from a portability standpoint */
 
     p = strrchr(argv[0], '/');
-    __progname = (p && p[1]) ? p + 1 : argv[0];
+    tftpd_progname = (p && p[1]) ? p + 1 : argv[0];
 
-    openlog(__progname, LOG_PID | LOG_NDELAY, LOG_DAEMON);
+    openlog(tftpd_progname, LOG_PID | LOG_NDELAY, LOG_DAEMON);
 
     srand(time(NULL) ^ getpid());
 
@@ -493,6 +497,17 @@ int main(int argc, char **argv)
             }
             rewrite_file = optarg;
             break;
+        case OPT_MAP_STEPS:
+        {
+            unsigned long steps = strtoul(optarg, &ep, 0);
+            if (*optarg && *ep && steps > 0 && steps <= INT_MAX) {
+                deadman_max_steps = steps;
+            } else {
+                syslog(LOG_ERR, "Bad --map-steps option: %s", optarg);
+                exit(EX_USAGE);
+            }
+            break;
+        }
 #endif
         case 'v':
             verbosity++;
@@ -874,9 +889,7 @@ int main(int argc, char **argv)
         set_socket_nonblock(fd, 0);
 #endif
 
-        fromlen = sizeof(from);
-        n = myrecvfrom(fd, buf, sizeof(buf), 0,
-                       (struct sockaddr *)&from, &fromlen, &myaddr);
+        n = myrecvfrom(fd, buf, sizeof(buf), 0, &from, &myaddr);
 
         if (n < 0) {
             if (E_WOULD_BLOCK(errno) || errno == EINTR) {
@@ -938,14 +951,14 @@ int main(int argc, char **argv)
        syslog daemon gets restarted by the time we get here. */
     if (secure && standalone) {
         closelog();
-        openlog(__progname, LOG_PID | LOG_NDELAY, LOG_DAEMON);
+        openlog(tftpd_progname, LOG_PID | LOG_NDELAY, LOG_DAEMON);
     }
 
 #ifdef HAVE_TCPWRAPPERS
     /* Verify if this was a legal request for us.  This has to be
        done before the chroot, while /etc is still accessible. */
     request_init(&wrap_request,
-                 RQ_DAEMON, __progname,
+                 RQ_DAEMON, tftpd_progname,
                  RQ_FILE, fd,
                  RQ_CLIENT_SIN, &from, RQ_SERVER_SIN, &myaddr, 0);
     sock_methods(&wrap_request);
@@ -977,21 +990,29 @@ int main(int argc, char **argv)
         exit(EX_IOERR);
     }
 
-    /* Set up the supplementary group access list if possible */
-    /* /etc/group still need to be accessible at this point */
+    /* Set up the supplementary group access list if possible
+       /etc/group still need to be accessible at this point.
+       If we get EPERM, this is already a restricted process, e.g.
+       using user namespaces on Linux. */
+    die = 0;
+#ifdef HAVE_SETGROUPS
+    setrv = setgroups(0, NULL);
+    if (setrv && errno != EPERM) {
+	syslog(LOG_ERR, "cannot clear group list");
+	die = EX_OSERR;
+    }
+#endif
 #ifdef HAVE_INITGROUPS
     setrv = initgroups(user, pw->pw_gid);
-    if (setrv) {
+    if (!setrv) {
+	die = 0;
+    } else if (errno != EPERM) {
         syslog(LOG_ERR, "cannot set groups for user %s", user);
-        exit(EX_OSERR);
-    }
-#else
-#ifdef HAVE_SETGROUPS
-    if (setgroups(0, NULL)) {
-        syslog(LOG_ERR, "cannot clear group list");
+	die = EX_OSERR;
     }
 #endif
-#endif
+    if (die)
+	exit(die);
 
     /* Chroot and drop privileges */
     if (secure) {
@@ -1003,19 +1024,30 @@ int main(int argc, char **argv)
         chdir("/");             /* Cygwin chroot() bug workaround */
 #endif
     }
-#ifdef HAVE_SETREGID
+
+#ifdef HAVE_SETRESGID
+    setrv = setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid);
+#elif defined(HAVE_SETREGID)
     setrv = setregid(pw->pw_gid, pw->pw_gid);
 #else
     setrv = setegid(pw->pw_gid) || setgid(pw->pw_gid);
 #endif
+    if (setrv && errno == EPERM) {
+	setrv = 0;		/* Assume already restricted by system policy */
+    }
 
-#ifdef HAVE_SETREUID
+#ifdef HAVE_SETRESUID
+    setrv = setrv || setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid);
+#elif defined(HAVE_SETREUID)
     setrv = setrv || setreuid(pw->pw_uid, pw->pw_uid);
 #else
     /* Important: setuid() must come first */
     setrv = setrv || setuid(pw->pw_uid) ||
         (geteuid() != pw->pw_uid && seteuid(pw->pw_uid));
 #endif
+    if (setrv && errno == EPERM) {
+	setrv = 0;		/* Assume already restricted by system policy */
+    }
 
     if (setrv) {
         syslog(LOG_ERR, "cannot drop privileges: %m");
@@ -1039,23 +1071,16 @@ int main(int argc, char **argv)
     tp = (struct tftphdr *)buf;
     tp_opcode = ntohs(tp->th_opcode);
     if (tp_opcode == RRQ || tp_opcode == WRQ)
-        tftp(tp, n);
+	tftp(tp, n);
     exit(0);
 }
 
-static char *rewrite_access(char *, int, const char **);
+static char *rewrite_access(const struct formats *,
+			    char *, int, int, const char **);
 static int validate_access(char *, int, const struct formats *, const char **);
 static void tftp_sendfile(const struct formats *, struct tftphdr *, int);
 static void tftp_recvfile(const struct formats *, struct tftphdr *, int);
 
-struct formats {
-    const char *f_mode;
-    char *(*f_rewrite) (char *, int, const char **);
-    int (*f_validate) (char *, int, const struct formats *, const char **);
-    void (*f_send) (const struct formats *, struct tftphdr *, int);
-    void (*f_recv) (const struct formats *, struct tftphdr *, int);
-    int f_convert;
-};
 static const struct formats formats[] = {
     {
     "netascii", rewrite_access, validate_access, tftp_sendfile,
@@ -1112,9 +1137,9 @@ int tftp(struct tftphdr *tp, int size)
                 nak(EBADOP, "Unknown mode");
                 exit(0);
             }
-            if (!(filename =
-                  (*pf->f_rewrite) (origfilename, tp_opcode,
-                                    &errmsgptr))) {
+	    file = NULL;
+            if (!(filename = (*pf->f_rewrite)
+		  (pf, origfilename, tp_opcode, from.sa.sa_family, &errmsgptr))) {
                 nak(EACCESS, errmsgptr);        /* File denied by mapping rule */
                 exit(0);
             }
@@ -1137,12 +1162,18 @@ int tftp(struct tftphdr *tp, int size)
                            tmp_p, origfilename,
                            filename);
             }
-            ecode =
-                (*pf->f_validate) (filename, tp_opcode, pf, &errmsgptr);
-            if (ecode) {
-                nak(ecode, errmsgptr);
-                exit(0);
-            }
+	    /*
+	     * If "file" is already set, then a file was already validated
+	     * and opened during remap processing.
+	     */
+	    if (!file) {
+		ecode =
+		    (*pf->f_validate) (filename, tp_opcode, pf, &errmsgptr);
+		if (ecode) {
+		    nak(ecode, errmsgptr);
+		    exit(0);
+		}
+	    }
             opt = ++cp;
         } else if (argn & 1) {
             val = ++cp;
@@ -1229,7 +1260,7 @@ static int set_blksize2(uintmax_t *vp)
 static int set_rollover(uintmax_t *vp)
 {
     uintmax_t ro = *vp;
-    
+
     if (ro > 65535)
 	return 0;
 
@@ -1328,7 +1359,7 @@ static void do_opt(const char *opt, const char *val, char **ap)
                     nak(EOPTNEG, "Insufficient space for options");
                     exit(0);
                 }
-		
+
 		memcpy(p, opt, optlen+1);
 		p += optlen+1;
 		memcpy(p, retbuf, retlen+1);
@@ -1398,12 +1429,12 @@ static int rewrite_macros(char macro, char *output)
 /*
  * Modify the filename, if applicable.  If it returns NULL, deny the access.
  */
-static char *rewrite_access(char *filename, int mode, const char **msg)
+static char *rewrite_access(const struct formats *pf, char *filename,
+			    int mode, int af, const char **msg)
 {
     if (rewrite_rules) {
         char *newname =
-            rewrite_string(filename, rewrite_rules,
-			   mode != RRQ ? 'P' : 'G',
+            rewrite_string(pf, filename, rewrite_rules, mode, af,
                            rewrite_macros, msg);
         filename = newname;
     }
@@ -1411,15 +1442,17 @@ static char *rewrite_access(char *filename, int mode, const char **msg)
 }
 
 #else
-static char *rewrite_access(char *filename, int mode, const char **msg)
+static char *rewrite_access(const struct formats *pf, char *filename,
+			    int mode, int af, const char **msg)
 {
+    (void)pf;
     (void)mode;                 /* Avoid warning */
     (void)msg;
+    (void)af;
     return filename;
 }
 #endif
 
-static FILE *file;
 /*
  * Validate file access.  Since we
  * have no uid or gid, for now require
@@ -1644,17 +1677,21 @@ static void tftp_sendfile(const struct formats *pf, struct tftphdr *oap, int oac
 /*
  * Receive a file.
  */
-static void tftp_recvfile(const struct formats *pf, struct tftphdr *oap, int oacklen)
+static void tftp_recvfile(const struct formats *pf,
+			  struct tftphdr *oack, int oacklen)
 {
     struct tftphdr *dp;
     int n, size;
     /* These are "static" to avoid longjmp funnies */
+    static struct tftphdr *oap;
     static struct tftphdr *ap;  /* ack buffer */
     static u_short block = 0;
     static int acksize;
     u_short dp_opcode, dp_block;
     unsigned long r_timeout;
 
+    oap = oack;
+
     dp = w_init();
     do {
         timeout = rexmtval;
diff --git a/tftpd/tftpd.h b/tftpd/tftpd.h
index e1d8bf0..277e5d2 100644
--- a/tftpd/tftpd.h
+++ b/tftpd/tftpd.h
@@ -23,4 +23,13 @@ char *tfstrdup(const char *);
 
 extern int verbosity;
 
+struct formats {
+    const char *f_mode;
+    char *(*f_rewrite) (const struct formats *, char *, int, int, const char **);
+    int (*f_validate) (char *, int, const struct formats *, const char **);
+    void (*f_send) (const struct formats *, struct tftphdr *, int);
+    void (*f_recv) (const struct formats *, struct tftphdr *, int);
+    int f_convert;
+};
+
 #endif
diff --git a/version b/version
index a75b92f..d346e2a 100644
--- a/version
+++ b/version
@@ -1 +1 @@
-5.1
+5.3