src: Add GPLv2+ header to .c files of recent creation

This patch comes after a proposal of mine at NFWS 2022 that resulted in
agreement to license recent .c files under GPLv2+ by the attendees at this
meeting:

- Stefano Brivio
- Fernando F. Mancera
- Phil Sutter
- Jozsef Kadlecsik
- Florian Westphal
- Laura Garcia
- Arturo Borrero
- Pablo Neira

It has already happened that one of the external library dependencies
was moved to GPLv3+ (libreadline), resulting in a change to libedit by
default in b4dded0ca78d ("configure: default to libedit for cli").

I have added the GPLv2+ header to the following files:

                        Authors
                        -------
src/cmd.c               Pablo
src/fib.c               Florian
src/hash.c              Pablo
src/iface.c             Pablo
src/json.c              Phil + fixes from occasional contributors
src/libnftables.c       Eric Leblond and Phil
src/mergesort.c         Elise Lenion
src/misspell.c          Pablo
src/mnl.c               Pablo + fixes from occasional contributors
src/monitor.c           Arturo
src/numgen.c            Pablo
src/osf.c               Fernando
src/owner.c             Pablo
src/parser_json.c       Phil + fixes from occasional contributors
src/print.c             Phil
src/xfrm.c              Florian
src/xt.c                Pablo

Eric Leblond and Elise Lennion did not attend NFWS 2022, but they
acknowledged this license update already in the past when I proposed
this to them in private emails.

Update COPYING file too to refer that we are now moving towards GPLv2 or
any later.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

18 files changed, 77 insertions, 29 deletions

diff --git a/COPYING b/COPYING
index bf7f06eb..a0dd81b9 100644
--- a/COPYING
+++ b/COPYING
@@ -1,8 +1,8 @@
+Original author of nftables distributed the code under the terms of the
+GPL version 2 *only*. New code though is moving to GPL version 2 or any
+later which is the preferred license for this project these days.
 
-nftables is distributed under the terms of the GPL version 2. Note that
-*only* version 2 of the GPL applies, not "any later version".
-
-Patrick McHardy <kaber@trash.net>
+Pablo Neira Ayuso <pablo@netfilter.org>
 
 -------------------------------------------------------------------------------
 
diff --git a/src/cmd.c b/src/cmd.c
index 63692422..9e375078 100644
--- a/src/cmd.c
+++ b/src/cmd.c
@@ -1,3 +1,11 @@
+/*
+ * Copyright (c) 2020 Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
+ */
+
 #include <erec.h>
 #include <mnl.h>
 #include <cmd.h>
diff --git a/src/fib.c b/src/fib.c
index c6ad0f9c..98c57868 100644
--- a/src/fib.c
+++ b/src/fib.c
@@ -4,8 +4,8 @@
  * Copyright (c) Red Hat GmbH.	Author: Florian Westphal <fw@strlen.de>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <nftables.h>
diff --git a/src/hash.c b/src/hash.c
index 42c50407..a3fd0872 100644
--- a/src/hash.c
+++ b/src/hash.c
@@ -4,8 +4,8 @@
  * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <nftables.h>
diff --git a/src/iface.c b/src/iface.c
index c0642e0c..3647778c 100644
--- a/src/iface.c
+++ b/src/iface.c
@@ -2,8 +2,8 @@
  * Copyright (c) 2015 Pablo Neira Ayuso <pablo@netfilter.org>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <stdio.h>
diff --git a/src/json.c b/src/json.c
index 89ff8a34..f57f2f77 100644
--- a/src/json.c
+++ b/src/json.c
@@ -1,3 +1,11 @@
+/*
+ * Copyright (c) Red Hat GmbH.  Author: Phil Sutter <phil@nwl.cc>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
+ */
+
 #define _GNU_SOURCE
 #include <stdio.h>
 #include <string.h>
diff --git a/src/libnftables.c b/src/libnftables.c
index a376825d..ec01a427 100644
--- a/src/libnftables.c
+++ b/src/libnftables.c
@@ -2,9 +2,8 @@
  * Copyright (c) 2017 Eric Leblond <eric@regit.org>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 #include <nftables/libnftables.h>
 #include <erec.h>
diff --git a/src/mergesort.c b/src/mergesort.c
index dca71422..a3a9d605 100644
--- a/src/mergesort.c
+++ b/src/mergesort.c
@@ -2,8 +2,8 @@
  * Copyright (c) 2017 Elise Lennion <elise.lennion@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <stdint.h>
diff --git a/src/misspell.c b/src/misspell.c
index 6536d755..8992c75e 100644
--- a/src/misspell.c
+++ b/src/misspell.c
@@ -1,3 +1,11 @@
+/*
+ * Copyright (c) 2018 Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
+ */
+
 #include <stdlib.h>
 #include <string.h>
 #include <limits.h>
diff --git a/src/mnl.c b/src/mnl.c
index e87b0338..62b0b59c 100644
--- a/src/mnl.c
+++ b/src/mnl.c
@@ -2,8 +2,8 @@
  * Copyright (c) 2013-2017 Pablo Neira Ayuso <pablo@netfilter.org>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  *
  * Development of this code funded by Astaro AG (http://www.astaro.com/)
  */
diff --git a/src/monitor.c b/src/monitor.c
index 4b55872b..9692b859 100644
--- a/src/monitor.c
+++ b/src/monitor.c
@@ -2,8 +2,8 @@
  * Copyright (c) 2015 Arturo Borrero Gonzalez <arturo@netfilter.org>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <string.h>
diff --git a/src/numgen.c b/src/numgen.c
index ea2b2626..256514d1 100644
--- a/src/numgen.c
+++ b/src/numgen.c
@@ -4,8 +4,8 @@
  * Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <nftables.h>
diff --git a/src/osf.c b/src/osf.c
index cb58315d..c611b542 100644
--- a/src/osf.c
+++ b/src/osf.c
@@ -1,3 +1,11 @@
+/*
+ * Copyright (c) 2018 Fernando Fernandez Mancera <ffmancera@riseup.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
+ */
+
 #include <nftables.h>
 #include <expression.h>
 #include <utils.h>
diff --git a/src/owner.c b/src/owner.c
index 20bed38b..c34b0c15 100644
--- a/src/owner.c
+++ b/src/owner.c
@@ -1,3 +1,11 @@
+/*
+ * Copyright (c) 2021 Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
+ */
+
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
diff --git a/src/parser_json.c b/src/parser_json.c
index 762e779d..ae683314 100644
--- a/src/parser_json.c
+++ b/src/parser_json.c
@@ -1,3 +1,11 @@
+/*
+ * Copyright (c) Red Hat GmbH.  Author: Phil Sutter <phil@nwl.cc>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
+ */
+
 #define _GNU_SOURCE
 #include <errno.h>
 #include <stdint.h> /* needed by gmputil.h */
diff --git a/src/print.c b/src/print.c
index d1b25e8b..4896e13c 100644
--- a/src/print.c
+++ b/src/print.c
@@ -2,9 +2,8 @@
  * Copyright (c) 2017 Phil Sutter <phil@nwl.cc>
  *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <stdarg.h>
diff --git a/src/xfrm.c b/src/xfrm.c
index 80f0ea03..b27821a9 100644
--- a/src/xfrm.c
+++ b/src/xfrm.c
@@ -1,9 +1,11 @@
 /*
  * XFRM (ipsec) expression
  *
+ * Copyright (c) Red Hat GmbH.  Author: Florian Westphal <fw@strlen.de>
+ *
  * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <nftables.h>
diff --git a/src/xt.c b/src/xt.c
index b75c94e8..9bfd8a2f 100644
--- a/src/xt.c
+++ b/src/xt.c
@@ -2,9 +2,9 @@
  * Copyright (c) 2013-2015 Pablo Neira Ayuso <pablo@netfilter.org>
  * Copyright (c) 2015 Arturo Borrero Gonzalez <arturo@debian.org>
  *
- * This program is free software; you can redistribute it and/or modifyi
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 (or any
+ * later) as published by the Free Software Foundation.
  */
 
 #include <stdlib.h>