Adding upstream version 0.2.0.upstream/0.2.0upstream

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

19 files changed, 696 insertions, 0 deletions

diff --git a/AUTHORS b/AUTHORS
new file mode 100644
index 0000000..49ac0d3
--- /dev/null
+++ b/AUTHORS
@@ -0,0 +1 @@
+Thorsten Alteholz <thorsten@alteholz.dev>
diff --git a/COPYING b/COPYING
new file mode 100644
index 0000000..d159169
--- /dev/null
+++ b/COPYING
@@ -0,0 +1,339 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Lesser General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
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+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
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+Activities other than copying, distribution and modification are not
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+You may charge a fee for the physical act of transferring a copy, and
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+These requirements apply to the modified work as a whole.  If
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+  8. If the distribution and/or use of the Program is restricted in
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+Software Foundation.  If the Program does not specify a version number of
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+Foundation.
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+  10. If you wish to incorporate parts of the Program into other free
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+                            NO WARRANTY
+
+  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
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+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
+REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
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+TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
+YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
+when it starts in an interactive mode:
+
+    Gnomovision version 69, Copyright (C) year name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.
diff --git a/ChangeLog b/ChangeLog
new file mode 100644
index 0000000..c0e4a3b
--- /dev/null
+++ b/ChangeLog
@@ -0,0 +1 @@
+Nothing to be entered here.
diff --git a/INSTALL b/INSTALL
new file mode 100644
index 0000000..3105a4a
--- /dev/null
+++ b/INSTALL
@@ -0,0 +1,4 @@
+./doit
+./configure
+make
+make install
diff --git a/Makefile.am b/Makefile.am
new file mode 100644
index 0000000..2e46050
--- /dev/null
+++ b/Makefile.am
@@ -0,0 +1,29 @@
+#
+#   force-ip-protocol
+#   Copyright (C) 2023 Thorsten Alteholz
+#
+#   This program is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, version 2 of the License.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+ACLOCAL_AMFLAGS = -I m4
+
+lib_LTLIBRARIES=libforce-ip-protocol-ipv4.la libforce-ip-protocol-ipv6.la
+
+libforce_ip_protocol_ipv6_la_SOURCES=force-ip-protocol-ipv4-or-ipv6.c
+libforce_ip_protocol_ipv6_la_CFLAGS=-fPIC -DUSE_IPV6
+libforce_ip_protocol_ipv6_la_LDFLAGS= -shared -fPIC
+
+libforce_ip_protocol_ipv4_la_SOURCES=force-ip-protocol-ipv4-or-ipv6.c
+libforce_ip_protocol_ipv4_la_CFLAGS=-fPIC -DUSE_IPV4
+libforce_ip_protocol_ipv4_la_LDFLAGS= -shared -fPIC
+
diff --git a/NEWS b/NEWS
new file mode 100644
index 0000000..497d972
--- /dev/null
+++ b/NEWS
@@ -0,0 +1 @@
+no NEWS are good NEWS
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..3757427
--- /dev/null
+++ b/README.md
@@ -0,0 +1,26 @@
+# force-ip-protocol
+
+## Description
+
+This library forces other software to use only IPv4 or IPv6 for network connections.
+
+A library will be LD_PRELOADed which replaces function getaddrinfo()
+by its own version. This version limits the available sockets to ones of
+type PF_INET/PF_INTE6 and such limits all network traffic to a certain protocol
+
+## Installation
+
+Please see INSTALL.
+
+## Usage
+
+ipv4  wget http://www.t-online.de
+
+## Authors and acknowledgment
+
+Please see AUTHORS.
+
+## License
+
+This software is licensed under GPL-2.0-only.
+
diff --git a/config.h.in b/config.h.in
new file mode 100644
index 0000000..39aba0a
--- /dev/null
+++ b/config.h.in
@@ -0,0 +1,69 @@
+/* config.h.in.  Generated from configure.ac by autoheader.  */
+
+/* Define to 1 if you have the <dlfcn.h> header file. */
+#undef HAVE_DLFCN_H
+
+/* Define to 1 if you have the <inttypes.h> header file. */
+#undef HAVE_INTTYPES_H
+
+/* Define to 1 if you have the <netdb.h> header file. */
+#undef HAVE_NETDB_H
+
+/* Define to 1 if you have the <stdint.h> header file. */
+#undef HAVE_STDINT_H
+
+/* Define to 1 if you have the <stdio.h> header file. */
+#undef HAVE_STDIO_H
+
+/* Define to 1 if you have the <stdlib.h> header file. */
+#undef HAVE_STDLIB_H
+
+/* Define to 1 if you have the <strings.h> header file. */
+#undef HAVE_STRINGS_H
+
+/* Define to 1 if you have the <string.h> header file. */
+#undef HAVE_STRING_H
+
+/* Define to 1 if you have the <sys/socket.h> header file. */
+#undef HAVE_SYS_SOCKET_H
+
+/* Define to 1 if you have the <sys/stat.h> header file. */
+#undef HAVE_SYS_STAT_H
+
+/* Define to 1 if you have the <sys/types.h> header file. */
+#undef HAVE_SYS_TYPES_H
+
+/* Define to 1 if you have the <unistd.h> header file. */
+#undef HAVE_UNISTD_H
+
+/* Define to the sub-directory where libtool stores uninstalled libraries. */
+#undef LT_OBJDIR
+
+/* Name of package */
+#undef PACKAGE
+
+/* Define to the address where bug reports for this package should be sent. */
+#undef PACKAGE_BUGREPORT
+
+/* Define to the full name of this package. */
+#undef PACKAGE_NAME
+
+/* Define to the full name and version of this package. */
+#undef PACKAGE_STRING
+
+/* Define to the one symbol short name of this package. */
+#undef PACKAGE_TARNAME
+
+/* Define to the home page for this package. */
+#undef PACKAGE_URL
+
+/* Define to the version of this package. */
+#undef PACKAGE_VERSION
+
+/* Define to 1 if all of the C90 standard headers exist (not just the ones
+   required in a freestanding environment). This macro is provided for
+   backward compatibility; new code need not use it. */
+#undef STDC_HEADERS
+
+/* Version number of package */
+#undef VERSION
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..ef5dd8d
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,35 @@
+#
+#   force-ip-protocol
+#   Copyright (C) 2023 Thorsten Alteholz
+#
+#   This program is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, version 2 of the License.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+AC_INIT([force-ip-protocol], [0.2.0], [thorsten@alteholz.dev])
+
+AM_INIT_AUTOMAKE
+LT_INIT()
+
+AC_CONFIG_MACRO_DIRS([m4])
+AC_CONFIG_HEADERS([config.h:config.h.in])
+AC_CHECK_HEADERS([sys/socket.h])
+AC_CHECK_HEADERS([netdb.h])
+
+
+AC_PROG_CC
+AC_CONFIG_FILES([Makefile])
+
+AC_ENABLE_SHARED
+AC_DISABLE_STATIC
+
+AC_OUTPUT
diff --git a/doc/HEADER.c b/doc/HEADER.c
new file mode 100644
index 0000000..f2e60fa
--- /dev/null
+++ b/doc/HEADER.c
@@ -0,0 +1,16 @@
+//
+//   force-ip-protocol
+//   Copyright (C) 2023 Thorsten Alteholz
+//
+//   This program is free software: you can redistribute it and/or modify
+//   it under the terms of the GNU General Public License as published by
+//   the Free Software Foundation, version 2 of the License.
+//
+//   This program is distributed in the hope that it will be useful,
+//   but WITHOUT ANY WARRANTY; without even the implied warranty of
+//   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//   GNU General Public License for more details.
+//
+//   You should have received a copy of the GNU General Public License
+//   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+//
diff --git a/doit b/doit
new file mode 100755
index 0000000..77efc95
--- /dev/null
+++ b/doit
@@ -0,0 +1,23 @@
+#!/bin/bash
+#
+#   force-ip-protocol
+#   Copyright (C) 2023 Thorsten Alteholz
+#
+#   This program is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, version 2 of the License.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+libtoolize
+aclocal
+autoconf
+autoheader
+automake --add-missing
diff --git a/doit.rm b/doit.rm
new file mode 100755
index 0000000..cfc2250
--- /dev/null
+++ b/doit.rm
@@ -0,0 +1,6 @@
+#!/bin/bash
+
+rm -f compile config.guess config.sub depcomp install-sh ltmain.sh missing
+
+rm -f aclocal.m4 configure Makefile.in
+rm -rf autom4te.cache/ m4/
diff --git a/example/example.ipv4.wget b/example/example.ipv4.wget
new file mode 100755
index 0000000..d0620ff
--- /dev/null
+++ b/example/example.ipv4.wget
@@ -0,0 +1,3 @@
+#!/bin/bash
+
+ipv4  wget http://www.t-online.de
diff --git a/example/example.ipv6.wget b/example/example.ipv6.wget
new file mode 100755
index 0000000..e11d795
--- /dev/null
+++ b/example/example.ipv6.wget
@@ -0,0 +1,3 @@
+#!/bin/bash
+
+ipv6  wget http://www.t-online.de
diff --git a/force-ip-protocol-ipv4-or-ipv6.c b/force-ip-protocol-ipv4-or-ipv6.c
new file mode 100644
index 0000000..bd366ff
--- /dev/null
+++ b/force-ip-protocol-ipv4-or-ipv6.c
@@ -0,0 +1,50 @@
+/*
+   force-ip-protocol
+   Copyright (C) 2023 Thorsten Alteholz
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, version 2 of the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+   usage: LD_PRELOAD=/path/to/library.so program args ...
+ */
+
+#include <config.h>
+
+#ifdef HAVE_SYS_SOCKET_H
+ #include <sys/socket.h>
+#endif
+
+#ifdef HAVE_NETDB_H
+ #include <netdb.h>
+#endif
+
+#ifdef HAVE_DLFCN_H
+ #include <dlfcn.h>
+#endif
+
+int getaddrinfo(const char *hostname, const char *servname,
+		const struct addrinfo *hints, struct addrinfo **res)
+{
+	int (*getaddrinfo_org)();
+	struct addrinfo *hints2 = (struct addrinfo *) hints;
+
+	getaddrinfo_org = dlsym(RTLD_NEXT, "getaddrinfo");
+#if defined USE_IPV4
+	hints2->ai_family = PF_INET;
+#elif defined USE_IPV6
+	hints2->ai_family = PF_INET6;
+#else
+#error You must define either USE_IPV4 or USE_IPV6.
+#endif
+
+	return (getaddrinfo_org(hostname, servname, hints2, res));
+}
diff --git a/ipv4 b/ipv4
new file mode 100755
index 0000000..a0621a9
--- /dev/null
+++ b/ipv4
@@ -0,0 +1,30 @@
+#!/bin/bash
+#
+#   force-ip-protocol
+#   Copyright (C) 2023 Thorsten Alteholz
+#
+#   This program is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, version 2 of the License.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+LIBNAME=libforce-ip-protocol-ipv4.so
+LIB=/usr/lib/*/$LIBNAME
+
+if [ -f $LIB ]; then
+  LD_PRELOAD=$LIB "$@"
+elif [ -f ./.libs/$LIBNAME ]; then
+  LD_PRELOAD=./.libs/$LIBNAME "$@"
+else
+  echo "$LIBNAME not found"
+  exit 1
+fi
+
diff --git a/ipv6 b/ipv6
new file mode 100755
index 0000000..2cd6f5c
--- /dev/null
+++ b/ipv6
@@ -0,0 +1,30 @@
+#!/bin/bash
+#
+#   force-ip-protocol
+#   Copyright (C) 2023 Thorsten Alteholz
+#
+#   This program is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, version 2 of the License.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+LIBNAME=libforce-ip-protocol-ipv6.so
+LIB=/usr/lib/*/$LIBNAME
+
+if [ -f $LIB ]; then
+  LD_PRELOAD=$LIB "$@"
+elif [ -f ./.libs/$LIBNAME ]; then
+  LD_PRELOAD=./.libs/$LIBNAME "$@"
+else
+  echo "$LIBNAME not found"
+  exit 1
+fi
+
diff --git a/man/ipv4.1 b/man/ipv4.1
new file mode 100644
index 0000000..66a1a98
--- /dev/null
+++ b/man/ipv4.1
@@ -0,0 +1,15 @@
+.\"TOPICS "Topics:"
+.TH IPV4 1 "May" "ipv4" ""
+.SH "NAME"
+ipv4 \- force other software to use only IPv4 for network connections
+
+.SH "DESCRIPTION"
+
+This software LD_PRELOADs a library which replaces function getaddrinfo()
+by its own version. This version limits the available sockets to ones of
+type PF_INET and such limits all network traffic to IPv4.
+
+.SH "AUTHORS"
+Authors and contributors are listed in the AUTHORS file in the source
+distribution.
+
diff --git a/man/ipv6.1 b/man/ipv6.1
new file mode 100644
index 0000000..113e8fe
--- /dev/null
+++ b/man/ipv6.1
@@ -0,0 +1,15 @@
+.\"TOPICS "Topics:"
+.TH IPV6 1 "May" "ipv6" ""
+.SH "NAME"
+ipv6 \- force other software to use only IPv6 for network connections
+
+.SH "DESCRIPTION"
+
+This software LD_PRELOADs a library which replaces function getaddrinfo()
+by its own version. This version limits the available sockets to ones of
+type PF_INET6 and such limits all network traffic to IPv6.
+
+.SH "AUTHORS"
+Authors and contributors are listed in the AUTHORS file in the source
+distribution.
+