initrd: add configuration generator

nm-initrd-generator scans the command line for options relevant to network
configuration and creates configuration files for an early instance of
NetworkManager run from the initial ramdisk during early boot.

.gitignore

@@ -252,6 +252,7 @@ test-*.trs
 /src/dhcp/tests/test-dhcp-options
 /src/dhcp/tests/test-dhcp-utils
 /src/dnsmasq/tests/test-dnsmasq-utils
+/src/initrd/nm-initrd-generator
 /src/initrd/tests/test-cmdline-reader
 /src/initrd/tests/test-ibft-reader
 /src/nm-iface-helper

Makefile.am

@@ -1936,6 +1936,24 @@ src_initrd_libnmi_core_la_SOURCES = \
 	src/initrd/nmi-ibft-reader.c \
 	$(NULL)
 
+libexec_PROGRAMS += src/initrd/nm-initrd-generator
+
+src_initrd_nm_initrd_generator_CPPFLAGS = \
+	$(src_cppflags)
+
+src_initrd_nm_initrd_generator_SOURCES = \
+	src/initrd/nm-initrd-generator.c
+
+src_initrd_nm_initrd_generator_LDADD = \
+	libnm-core/libnm-core.la \
+	src/initrd/libnmi-core.la \
+	src/libNetworkManagerBase.la \
+	$(GLIB_LIBS)
+
+src_initrd_nm_initrd_generator_LDFLAGS = \
+	-Wl,--version-script="$(srcdir)/linker-script-binary.ver" \
+	$(SANITIZER_EXEC_LDFLAGS)
+
 check_programs += src/initrd/tests/test-ibft-reader
 
 src_initrd_tests_test_ibft_reader_CPPFLAGS = \
@@ -2166,6 +2184,7 @@ src_initrd_tests_test_cmdline_reader_LDADD = \
 	$(GLIB_LIBS)
 
 $(src_initrd_libnmi_core_la_OBJECTS): $(libnm_core_lib_h_pub_mkenums)
+$(src_initrd_nm_initrd_generator_OBJECTS): $(libnm_core_lib_h_pub_mkenums)
 $(src_initrd_tests_test_cmdline_reader_OBJECTS): $(libnm_core_lib_h_pub_mkenums)
 $(src_initrd_tests_test_ibft_reader_OBJECTS): $(libnm_core_lib_h_pub_mkenums)
 
@@ -4861,6 +4880,7 @@ man_pages += \
 	man/NetworkManager.8 \
 	man/NetworkManager.conf.5 \
 	man/nm-online.1 \
+	man/nm-initrd-generator.8 \
 	man/nmcli-examples.7 \
 	man/nmcli.1 \
 	man/nmtui.1

contrib/fedora/rpm/NetworkManager.spec

@@ -687,6 +687,7 @@ fi
 %{_libexecdir}/nm-dhcp-helper
 %{_libexecdir}/nm-dispatcher
 %{_libexecdir}/nm-iface-helper
+%{_libexecdir}/nm-initrd-generator
 %dir %{_libdir}/%{name}
 %dir %{nmplugindir}
 %{nmplugindir}/libnm-settings-plugin*.so

docs/api/Makefile.am

@@ -83,6 +83,7 @@ content_files = \
 	$(top_builddir)/man/nmcli.xml \
 	$(top_builddir)/man/nmtui.xml \
 	$(top_builddir)/man/nm-online.xml \
+	$(top_builddir)/man/nm-initrd-generator.xml \
 	$(top_builddir)/man/NetworkManager.xml \
 	$(top_builddir)/man/NetworkManager.conf.xml \
 	$(top_builddir)/man/nmcli-examples.xml \

docs/api/network-manager-docs.xml

@@ -77,6 +77,7 @@
     <xi:include href="../../man/nm-settings-keyfile.xml"><xi:fallback /></xi:include>
     <xi:include href="../../man/nm-settings-ifcfg-rh.xml"><xi:fallback /></xi:include>
     <xi:include href="../../man/nm-online.xml"/>
+    <xi:include href="../../man/nm-initrd-generator.xml"/>
     <xi:include href="../../man/nm-openvswitch.xml"/>
   </part>
 

man/nm-initrd-generator.xml

+<?xml version='1.0'?>
+<?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" [
+<!ENTITY % entities SYSTEM "common.ent" >
+%entities;
+]>
+
+<!--
+  nm-initrd-generator(8) manual page
+
+  Copyright 2018 Red Hat, Inc.
+
+  Permission is granted to copy, distribute and/or modify this document
+  under the terms of the GNU Free Documentation License, Version 1.1
+  or any later version published by the Free Software Foundation;
+  with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
+  Texts. You may obtain a copy of the GNU Free Documentation License
+  from the Free Software Foundation by visiting their Web site or by
+  writing to:
+
+  Free Software Foundation, Inc.,
+  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+-->
+
+<refentry id='nm-initrd-generator'>
+
+  <refentryinfo>
+    <title>nm-initrd-generator</title>
+    <author>NetworkManager developers</author>
+  </refentryinfo>
+
+  <refmeta>
+    <refentrytitle>nm-initrd-generator</refentrytitle>
+    <manvolnum>8</manvolnum>
+    <refmiscinfo class="source">NetworkManager</refmiscinfo>
+    <refmiscinfo class="manual">System Administration</refmiscinfo>
+    <refmiscinfo class="version">&NM_VERSION;</refmiscinfo>
+  </refmeta>
+
+  <refnamediv>
+    <refname>nm-initrd-generator</refname>
+    <refpurpose>early boot NetworkManager configuration generator</refpurpose>
+  </refnamediv>
+
+  <refsynopsisdiv id='synopsis'>
+    <cmdsynopsis>
+      <command>nm-initrd-generator</command>
+      <arg choice="opt" rep="repeat"><replaceable>OPTIONS</replaceable></arg>
+      <arg choice="plain">--</arg>
+      <arg choice="opt" rep="repeat"><replaceable>CMDLINE</replaceable></arg>
+    </cmdsynopsis>
+  </refsynopsisdiv>
+
+  <refsect1 id='description'><title>Description</title>
+    <para><command>nm-initrd-generator</command> scans the command line for options
+    relevant to network configuration and creates configuration files for an early
+    instance of NetworkManager run from the initial ramdisk during early boot.</para>
+  </refsect1>
+
+  <refsect1 id='options'><title>Options</title>
+    <variablelist>
+      <varlistentry>
+        <term>
+          <group choice='plain'>
+            <arg choice='plain'><option>-c</option></arg>
+            <arg choice='plain'><option>--connections-dir</option></arg>
+          </group>
+          <arg choice='plain'><replaceable>path</replaceable></arg>
+        </term>
+
+        <listitem>
+          <para>Output connection directory.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term>
+          <group choice='plain'>
+            <arg choice='plain'><option>-d</option></arg>
+            <arg choice='plain'><option>--sysfs-dir</option></arg>
+          </group>
+          <arg choice='plain'><replaceable>path</replaceable></arg>
+        </term>
+
+        <listitem>
+          <para>The sysfs mount point.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term>
+          <group choice='plain'>
+            <arg choice='plain'><option>-s</option></arg>
+            <arg choice='plain'><option>--stdout</option></arg>
+          </group>
+        </term>
+
+        <listitem>
+          <para>Dump connections to standard output. Useful for debugging.</para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><replaceable>CMDLINE</replaceable></term>
+
+        <listitem>
+          <para>The options that appear on the kernel command line. The following options are recognized:</para>
+
+          <simplelist>
+            <member><option>ip</option></member>
+            <member><option>rd.route</option></member>
+            <member><option>bridge</option></member>
+            <member><option>bond</option></member>
+            <member><option>team</option></member>
+            <member><option>vlan</option></member>
+            <member><option>bootdev</option></member>
+            <member><option>nameserver</option></member>
+            <member><option>rd.peerdns</option></member>
+            <member><option>rd.bootif</option></member>
+            <member><option>BOOTIF</option></member>
+          </simplelist>
+
+          <para>Please consult the <citerefentry><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+          manual for the documentation of the precise format of the values supported.</para>
+        </listitem>
+      </varlistentry>
+    </variablelist>
+  </refsect1>
+
+  <refsect1 id='exit_status'><title>Exit Status</title>
+    <para><command>nm-initrd-generator</command> exits with status 0. It ignores unrecognized
+    options and prints an error message if it encounters a malformed option.</para>
+  </refsect1>
+
+  <refsect1 id='see_also'><title>See Also</title>
+    <para><link linkend='dracut.cmdline'><citerefentry><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry></link>,
+    <link linkend='NetworkManager'><citerefentry><refentrytitle>NetworkManager</refentrytitle><manvolnum>8</manvolnum></citerefentry></link>.</para>
+  </refsect1>
+</refentry>

src/initrd/nm-initrd-generator.c

+/* NetworkManager initrd configuration generator
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ * Copyright (C) 2018 Red Hat, Inc.
+ */
+
+#include "nm-default.h"
+#include "nm-core-utils.h"
+#include "nm-core-internal.h"
+#include "nm-keyfile-internal.h"
+
+#include "nm-initrd-generator.h"
+
+/*****************************************************************************/
+
+#define _NMLOG(level, domain, ...) \
+    nm_log ((level), (domain), NULL, NULL, \
+            "initrd-generator: " _NM_UTILS_MACRO_FIRST (__VA_ARGS__) \
+            _NM_UTILS_MACRO_REST (__VA_ARGS__))
+
+/*****************************************************************************/
+
+static void
+output_conn (gpointer key, gpointer value, gpointer user_data)
+{
+	const char *basename = key;
+	NMConnection *connection = value;
+	char *connections_dir = user_data;
+	GKeyFile *file;
+	gs_free char *data = NULL;
+	GError *error = NULL;
+	gsize len;
+
+	if (!nm_connection_normalize (connection, NULL, NULL, &error)) {
+		g_print ("%s\n", error->message);
+		g_error_free (error);
+		return;
+	}
+
+	file = nm_keyfile_write (connection, NULL, NULL, &error);
+	if (file == NULL) {
+		g_print ("%s\n", error->message);
+		g_error_free (error);
+		return;
+	}
+
+	data = g_key_file_to_data (file, &len, &error);
+	if (!data) {
+		g_print ("%s\n", error->message);
+		g_error_free (error);
+	} else if (connections_dir) {
+		char *filename = g_build_filename (connections_dir, basename, NULL);
+
+		if (!nm_utils_file_set_contents (filename, data, len, 0600, &error)) {
+			g_print ("%s\n", error->message);
+			g_error_free (error);
+		}
+		g_free (filename);
+	} else {
+		g_print ("\n*** Connection '%s' ***\n\n%s\n", basename, data);
+	}
+
+	g_key_file_free (file);
+}
+
+#define DEFAULT_CONNECTIONS_DIR  NMRUNDIR "/system-connections"
+#define DEFAULT_SYSFS_DIR        "/sys"
+
+int
+main (int argc, char *argv[])
+{
+	GHashTable *connections;
+	gs_free char *connections_dir = NULL;
+	gs_free char *sysfs_dir = NULL;
+	gboolean dump_to_stdout = FALSE;
+	gs_strfreev char **remaining = NULL;
+	GOptionEntry option_entries[] = {
+		{ "connections-dir", 'c', 0, G_OPTION_ARG_FILENAME, &connections_dir, "Output connection directory", DEFAULT_CONNECTIONS_DIR },
+		{ "sysfs-dir", 'd', 0, G_OPTION_ARG_FILENAME, &sysfs_dir, "The sysfs mount point", DEFAULT_SYSFS_DIR },
+		{ "stdout", 's', 0, G_OPTION_ARG_NONE, &dump_to_stdout, "Dump connections to standard output", NULL },
+		{ G_OPTION_REMAINING, '\0', 0, G_OPTION_ARG_STRING_ARRAY, &remaining, NULL, NULL },
+		{ NULL }
+	};
+	GOptionContext *option_context;
+	GError *error = NULL;
+
+	option_context = g_option_context_new ("-- [ip=...] [rd.route=...] [bridge=...] [bond=...] [team=...] [vlan=...] "
+	                                       "[bootdev=...] [nameserver=...] [rd.peerdns=...] [rd.bootif=...] [BOOTIF=...] ... ");
+
+	g_option_context_set_summary (option_context, "Generate early NetworkManager configuration.");
+	g_option_context_set_description (option_context,
+		"This tool scans the command line for options relevant to network\n"
+		"configuration and creates configuration files for an early instance\n"
+		"of NetworkManager run from the initial ramdisk during early boot.");
+	g_option_context_add_main_entries (option_context, option_entries, GETTEXT_PACKAGE);
+
+	if (!g_option_context_parse (option_context, &argc, &argv, &error)) {
+		_LOGW (LOGD_CORE, "%s\n", error->message);
+		return 1;
+	}
+
+	if (!remaining) {
+		/* No arguments, no networking. Don't bother. */
+		return 0;
+	}
+
+	if (!connections_dir)
+		connections_dir = g_strdup (DEFAULT_CONNECTIONS_DIR);
+	if (!sysfs_dir)
+		sysfs_dir = g_strdup (DEFAULT_SYSFS_DIR);
+	if (dump_to_stdout)
+		g_clear_pointer (&connections_dir, g_free);
+
+	if (connections_dir && g_mkdir_with_parents (connections_dir, 0755) != 0) {
+		_LOGW (LOGD_CORE, "%s: %s\n", connections_dir, strerror (errno));
+		return 1;
+	}
+
+	connections = nmi_cmdline_reader_parse (sysfs_dir, remaining);
+	g_hash_table_foreach (connections, output_conn, connections_dir);
+	g_hash_table_destroy (connections);
+
+	return 0;
+}