settings: add match for proc cmdline

Add a new "kernel-command-line" match option to nm-settings. It allows
to disable a network connection configuration if a pattern is found or
is not found in /proc/cmdline.

clients/common/nm-meta-setting-desc.c

@@ -3459,6 +3459,35 @@ _get_fcn_match_interface_name (ARGS_GET_FCN)
 	RETURN_STR_TO_FREE (g_string_free (str, FALSE));
 }
 
+static gconstpointer
+_get_fcn_match_kernel_command_line (ARGS_GET_FCN)
+{
+	NMSettingMatch *s_match = NM_SETTING_MATCH (setting);
+	GString *str = NULL;
+	guint i, num;
+
+	RETURN_UNSUPPORTED_GET_TYPE ();
+
+	num = nm_setting_match_get_num_kernel_command_lines (s_match);
+	for (i = 0; i < num; i++) {
+		const char *name;
+
+		name = nm_setting_match_get_kernel_command_line (s_match, i);
+		if (!name || !name[0])
+			continue;
+		if (!str)
+			str = g_string_new ("");
+		else
+			g_string_append_c (str, ESCAPED_TOKENS_WITH_SPACES_DELIMTER);
+		nm_utils_escaped_tokens_escape_gstr (name, ESCAPED_TOKENS_WITH_SPACES_DELIMTERS, str);
+	}
+
+	NM_SET_OUT (out_is_default, num == 0);
+	if (!str)
+		return NULL;
+	RETURN_STR_TO_FREE (g_string_free (str, FALSE));
+}
+
 static gconstpointer
 _get_fcn_olpc_mesh_ssid (ARGS_GET_FCN)
 {
@@ -6209,6 +6238,22 @@ static const NMMetaPropertyInfo *const property_infos_MATCH[] = {
 	        ),
 	    ),
 	),
+	PROPERTY_INFO_WITH_DESC (NM_SETTING_MATCH_KERNEL_COMMAND_LINE,
+	    .property_type = DEFINE_PROPERTY_TYPE (
+	        .get_fcn =                  _get_fcn_match_kernel_command_line,
+	        .set_fcn =                  _set_fcn_multilist,
+	        .set_supports_remove =      TRUE,
+	    ),
+	    .property_typ_data = DEFINE_PROPERTY_TYP_DATA (
+	        PROPERTY_TYP_DATA_SUBTYPE (multilist,
+	            .get_num_fcn_u   =      MULTILIST_GET_NUM_FCN_U       (NMSettingMatch, nm_setting_match_get_num_kernel_command_lines),
+	            .add2_fcn =             MULTILIST_ADD2_FCN            (NMSettingMatch, nm_setting_match_add_kernel_command_line),
+	            .remove_by_idx_fcn_u =  MULTILIST_REMOVE_BY_IDX_FCN_U (NMSettingMatch, nm_setting_match_remove_kernel_command_line),
+	            .remove_by_value_fcn =  MULTILIST_REMOVE_BY_VALUE_FCN (NMSettingMatch, nm_setting_match_remove_kernel_command_line_by_value),
+	            .strsplit_with_spaces = TRUE,
+	        ),
+	    ),
+	),
 	NULL
 };
 

clients/common/settings-docs.h.in

@@ -281,6 +281,7 @@
 #define DESCRIBE_DOC_NM_SETTING_MACVLAN_PROMISCUOUS N_("Whether the interface should be put in promiscuous mode.")
 #define DESCRIBE_DOC_NM_SETTING_MACVLAN_TAP N_("Whether the interface should be a MACVTAP.")
 #define DESCRIBE_DOC_NM_SETTING_MATCH_INTERFACE_NAME N_("A list of interface names to match. Each element is a shell wildcard pattern.  When an element is prefixed with exclamation mark (!) the condition is inverted. A candidate interface name is considered matching when both these conditions are satisfied: (a) any of the elements not prefixed with '!' matches or there aren't such elements; (b) none of the elements prefixed with '!' match.")
+#define DESCRIBE_DOC_NM_SETTING_MATCH_KERNEL_COMMAND_LINE N_("A list of kernel command line arguments to match. This may be used to check whether a specific kernel command line option is set (or if prefixed with the exclamation mark unset). The argument must either be a single word, or an assignment (i.e. two words, separated \"=\"). In the former case the kernel command line is searched for the word appearing as is, or as left hand side of an assignment. In the latter case, the exact assignment is looked for with right and left hand side matching.")
 #define DESCRIBE_DOC_NM_SETTING_OVS_BRIDGE_DATAPATH_TYPE N_("The data path type. One of \"system\", \"netdev\" or empty.")
 #define DESCRIBE_DOC_NM_SETTING_OVS_BRIDGE_FAIL_MODE N_("The bridge failure mode. One of \"secure\", \"standalone\" or empty.")
 #define DESCRIBE_DOC_NM_SETTING_OVS_BRIDGE_MCAST_SNOOPING_ENABLE N_("Enable or disable multicast snooping.")

libnm-core/nm-setting-match.c

@@ -20,6 +20,7 @@
 
 NM_GOBJECT_PROPERTIES_DEFINE (NMSettingMatch,
 	PROP_INTERFACE_NAME,
+	PROP_KERNEL_COMMAND_LINE,
 );
 
 /**
@@ -32,6 +33,7 @@ NM_GOBJECT_PROPERTIES_DEFINE (NMSettingMatch,
 struct _NMSettingMatch {
 	NMSetting parent;
 	GPtrArray *interface_name;
+	GPtrArray *kernel_command_line;
 };
 
 struct _NMSettingMatchClass {
@@ -191,6 +193,154 @@ nm_setting_match_get_interface_names (NMSettingMatch *setting, guint *length)
 
 /*****************************************************************************/
 
+/**
+ * nm_setting_match_get_num_kernel_command_lines:
+ * @setting: the #NMSettingMatch
+ *
+ * Returns: the number of configured kernel command line arguments
+ *
+ * Since: 1.26
+ **/
+guint
+nm_setting_match_get_num_kernel_command_lines (NMSettingMatch *setting)
+{
+	g_return_val_if_fail (NM_IS_SETTING_MATCH (setting), 0);
+
+	return setting->kernel_command_line->len;
+}
+
+/**
+ * nm_setting_match_get_kernel_command_line:
+ * @setting: the #NMSettingMatch
+ * @idx: index number of the kernel command line argument to return
+ *
+ * Returns: the kernel command line argument at index @idx
+ *
+ * Since: 1.26
+ **/
+const char *
+nm_setting_match_get_kernel_command_line (NMSettingMatch *setting, guint idx)
+{
+	g_return_val_if_fail (NM_IS_SETTING_MATCH (setting), NULL);
+
+	g_return_val_if_fail (idx < setting->kernel_command_line->len, NULL);
+
+	return setting->kernel_command_line->pdata[idx];
+}
+
+/**
+ * nm_setting_match_add_kernel_command_line:
+ * @setting: the #NMSettingMatch
+ * @kernel_command_line: the kernel command line argument to add
+ *
+ * Adds a new kernel command line argument to the setting.
+ *
+ * Since: 1.26
+ **/
+void
+nm_setting_match_add_kernel_command_line (NMSettingMatch *setting,
+                                          const char *kernel_command_line)
+{
+	g_return_if_fail (NM_IS_SETTING_MATCH (setting));
+	g_return_if_fail (kernel_command_line != NULL);
+	g_return_if_fail (kernel_command_line[0] != '\0');
+
+	g_ptr_array_add (setting->kernel_command_line, g_strdup (kernel_command_line));
+	_notify (setting, PROP_KERNEL_COMMAND_LINE);
+}
+
+/**
+ * nm_setting_match_remove_kernel_command_line:
+ * @setting: the #NMSettingMatch
+ * @idx: index number of the kernel command line argument
+ *
+ * Removes the kernel command line argument at index @idx.
+ *
+ * Since: 1.26
+ **/
+void
+nm_setting_match_remove_kernel_command_line (NMSettingMatch *setting, guint idx)
+{
+	g_return_if_fail (NM_IS_SETTING_MATCH (setting));
+
+	g_return_if_fail (idx < setting->kernel_command_line->len);
+
+	g_ptr_array_remove_index (setting->kernel_command_line, idx);
+	_notify (setting, PROP_KERNEL_COMMAND_LINE);
+}
+
+/**
+ * nm_setting_match_remove_kernel_command_line_by_value:
+ * @setting: the #NMSettingMatch
+ * @kernel_command_line: the kernel command line argument name to remove
+ *
+ * Removes @kernel_command_line.
+ *
+ * Returns: %TRUE if the kernel command line argument was found and removed; %FALSE if it was not.
+ *
+ * Since: 1.26
+ **/
+gboolean
+nm_setting_match_remove_kernel_command_line_by_value (NMSettingMatch *setting,
+                                                      const char *kernel_command_line)
+{
+	guint i;
+
+	g_return_val_if_fail (NM_IS_SETTING_MATCH (setting), FALSE);
+	g_return_val_if_fail (kernel_command_line != NULL, FALSE);
+	g_return_val_if_fail (kernel_command_line[0] != '\0', FALSE);
+
+	for (i = 0; i < setting->kernel_command_line->len; i++) {
+		if (nm_streq (kernel_command_line, setting->kernel_command_line->pdata[i])) {
+			g_ptr_array_remove_index (setting->kernel_command_line, i);
+			_notify (setting, PROP_KERNEL_COMMAND_LINE);
+			return TRUE;
+		}
+	}
+	return FALSE;
+}
+
+/**
+ * nm_setting_match_clear_kernel_command_lines:
+ * @setting: the #NMSettingMatch
+ *
+ * Removes all configured kernel command line arguments.
+ *
+ * Since: 1.26
+ **/
+void
+nm_setting_match_clear_kernel_command_lines (NMSettingMatch *setting)
+{
+	g_return_if_fail (NM_IS_SETTING_MATCH (setting));
+
+	if (setting->kernel_command_line->len != 0) {
+		g_ptr_array_set_size (setting->kernel_command_line, 0);
+		_notify (setting, PROP_KERNEL_COMMAND_LINE);
+	}
+}
+
+/**
+ * nm_setting_match_get_kernel_command_lines:
+ * @setting: the #NMSettingMatch
+ *
+ * Returns all the interface names.
+ *
+ * Returns: (transfer none): the configured interface names.
+ *
+ * Since: 1.26
+ **/
+const char *const *
+nm_setting_match_get_kernel_command_lines (NMSettingMatch *setting, guint *length)
+{
+	g_return_val_if_fail (NM_IS_SETTING_MATCH (setting), NULL);
+	g_return_val_if_fail (length, NULL);
+
+	NM_SET_OUT (length, setting->kernel_command_line->len);
+	return (const char *const *) setting->kernel_command_line->pdata;
+}
+
+/*****************************************************************************/
+
 static void
 get_property (GObject *object, guint prop_id,
               GValue *value, GParamSpec *pspec)
@@ -201,6 +351,9 @@ get_property (GObject *object, guint prop_id,
 	case PROP_INTERFACE_NAME:
 		g_value_take_boxed (value, _nm_utils_ptrarray_to_strv (self->interface_name));
 		break;
+	case PROP_KERNEL_COMMAND_LINE:
+		g_value_take_boxed (value, _nm_utils_ptrarray_to_strv (self->kernel_command_line));
+		break;
 	default:
 		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 		break;
@@ -218,6 +371,10 @@ set_property (GObject *object, guint prop_id,
 		g_ptr_array_unref (self->interface_name);
 		self->interface_name = _nm_utils_strv_to_ptrarray (g_value_get_boxed (value));
 		break;
+	case PROP_KERNEL_COMMAND_LINE:
+		g_ptr_array_unref (self->kernel_command_line);
+		self->kernel_command_line = _nm_utils_strv_to_ptrarray (g_value_get_boxed (value));
+		break;
 	default:
 		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 		break;
@@ -230,6 +387,7 @@ static void
 nm_setting_match_init (NMSettingMatch *setting)
 {
 	setting->interface_name = g_ptr_array_new_with_free_func (g_free);
+	setting->kernel_command_line = g_ptr_array_new_with_free_func (g_free);
 }
 
 /**
@@ -266,6 +424,19 @@ verify (NMSetting *setting, NMConnection *connection, GError **error)
 		}
 	}
 
+	for (k = 0; k < self->kernel_command_line->len; k++) {
+		char *kparam = (char*) g_ptr_array_index (self->kernel_command_line, k);
+		if (nm_streq0 (kparam, "")) {
+			g_set_error (error,
+			             NM_CONNECTION_ERROR,
+			             NM_CONNECTION_ERROR_INVALID_PROPERTY,
+			             _("is empty"));
+			g_prefix_error (error, "%s.%s: ", NM_SETTING_MATCH_SETTING_NAME,
+			                NM_SETTING_MATCH_KERNEL_COMMAND_LINE);
+			return FALSE;
+		}
+	}
+
 	return TRUE;
 }
 
@@ -275,6 +446,7 @@ finalize (GObject *object)
 	NMSettingMatch *self = NM_SETTING_MATCH (object);
 
 	g_ptr_array_unref (self->interface_name);
+	g_ptr_array_unref (self->kernel_command_line);
 
 	G_OBJECT_CLASS (nm_setting_match_parent_class)->finalize (object);
 }
@@ -312,6 +484,26 @@ nm_setting_match_class_init (NMSettingMatchClass *klass)
 	                        G_PARAM_READWRITE |
 	                        G_PARAM_STATIC_STRINGS);
 
+	/**
+	 * NMSettingMatch:kernel-command-line
+	 *
+	 * A list of kernel command line arguments to match. This may be used to check
+	 * whether a specific kernel command line option is set (or if prefixed with
+	 * the exclamation mark unset). The argument must either be a single word, or
+	 * an assignment (i.e. two words, separated "="). In the former case the kernel
+	 * command line is searched for the word appearing as is, or as left hand side
+	 * of an assignment. In the latter case, the exact assignment is looked for
+	 * with right and left hand side matching.
+	 *
+	 * Since: 1.26
+	 **/
+	obj_properties[PROP_KERNEL_COMMAND_LINE] =
+	    g_param_spec_boxed (NM_SETTING_MATCH_KERNEL_COMMAND_LINE, "", "",
+	                        G_TYPE_STRV,
+	                        NM_SETTING_PARAM_FUZZY_IGNORE |
+	                        G_PARAM_READWRITE |
+	                        G_PARAM_STATIC_STRINGS);
+
 	g_object_class_install_properties (object_class, _PROPERTY_ENUMS_LAST, obj_properties);
 
 	_nm_setting_class_commit (setting_class, NM_META_SETTING_TYPE_MATCH);

libnm-core/nm-setting-match.h

@@ -24,6 +24,7 @@ G_BEGIN_DECLS
 #define NM_SETTING_MATCH_SETTING_NAME      "match"
 
 #define NM_SETTING_MATCH_INTERFACE_NAME    "interface-name"
+#define NM_SETTING_MATCH_KERNEL_COMMAND_LINE    "kernel-command-line"
 
 typedef struct _NMSettingMatchClass NMSettingMatchClass;
 
@@ -49,6 +50,25 @@ NM_AVAILABLE_IN_1_14
 void nm_setting_match_clear_interface_names (NMSettingMatch *setting);
 NM_AVAILABLE_IN_1_14
 const char *const *nm_setting_match_get_interface_names (NMSettingMatch *setting, guint *length);
+
+
+NM_AVAILABLE_IN_1_26
+guint nm_setting_match_get_num_kernel_command_lines (NMSettingMatch *setting);
+NM_AVAILABLE_IN_1_26
+const char *nm_setting_match_get_kernel_command_line (NMSettingMatch *setting, guint idx);
+NM_AVAILABLE_IN_1_26
+void nm_setting_match_remove_kernel_command_line (NMSettingMatch *setting, guint idx);
+NM_AVAILABLE_IN_1_26
+gboolean nm_setting_match_remove_kernel_command_line_by_value (NMSettingMatch *setting,
+                                                               const char *kernel_command_line);
+NM_AVAILABLE_IN_1_26
+void nm_setting_match_add_kernel_command_line (NMSettingMatch *setting,
+                                               const char *kernel_command_line);
+NM_AVAILABLE_IN_1_26
+void nm_setting_match_clear_kernel_command_lines (NMSettingMatch *setting);
+NM_AVAILABLE_IN_1_26
+const char *const *nm_setting_match_get_kernel_command_lines (NMSettingMatch *setting, guint *length);
+
 G_END_DECLS
 
 #endif /* NM_SETTING_MATCH_H */

libnm/libnm.ver

@@ -1708,4 +1708,11 @@ global:
 	nm_setting_bridge_get_multicast_startup_query_count;
 	nm_setting_bridge_get_multicast_startup_query_interval;
 	nm_setting_connection_get_mud_url;
+	nm_setting_match_add_kernel_command_line;
+	nm_setting_match_clear_kernel_command_lines;
+	nm_setting_match_get_kernel_command_line;
+	nm_setting_match_get_kernel_command_lines;
+	nm_setting_match_get_num_kernel_command_lines;
+	nm_setting_match_remove_kernel_command_line;
+	nm_setting_match_remove_kernel_command_line_by_value;
 } libnm_1_24_0;

src/devices/nm-device.c

@@ -5999,7 +5999,6 @@ check_connection_compatible (NMDevice *self, NMConnection *connection, GError **
 	gs_free_error GError *local = NULL;
 	gs_free char *conn_iface = NULL;
 	NMDeviceClass *klass;
-	const char *const *patterns;
 	NMSettingMatch *s_match;
 
 	klass = NM_DEVICE_GET_CLASS (self);
@@ -6042,14 +6041,68 @@ check_connection_compatible (NMDevice *self, NMConnection *connection, GError **
 	s_match = (NMSettingMatch *) nm_connection_get_setting (connection,
 	                                                        NM_TYPE_SETTING_MATCH);
 	if (s_match) {
+		const char *const *patterns;
 		guint num_patterns = 0;
 
+		/* interface_names */
 		patterns = nm_setting_match_get_interface_names (s_match, &num_patterns);
 		if (!nm_wildcard_match_check (device_iface, patterns, num_patterns)) {
 			nm_utils_error_set_literal (error, NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,
 			                            "device does not satisfy match.interface-name property");
 			return FALSE;
 		}
+
+		{ /* kernel_command_line */
+			const char *const*proc_cmdline;
+			const char *const*proc_cmdline_i;
+			unsigned i;
+			gboolean pos_patterns = FALSE;
+
+			patterns = nm_setting_match_get_kernel_command_lines (s_match, &num_patterns);
+			proc_cmdline = nm_utils_proc_cmdline_split ();
+			for(i=0; i<num_patterns; i++) {
+				gboolean found = FALSE;
+				gboolean negative = FALSE;
+				const char *equal;
+				const char *patterns_i = patterns[i];
+
+				if(patterns_i[0] == '!') {
+					++patterns_i;
+					negative = TRUE;
+				} else {
+					pos_patterns = TRUE;
+				}
+				equal = strchr(patterns_i, '=');
+
+				proc_cmdline_i = proc_cmdline;
+				while (*proc_cmdline_i) {
+					if (equal) {  /* if pattern contains = compare full key=value */
+						found = nm_streq0(*proc_cmdline_i, patterns_i);
+					} else {      /* otherwise consider pattern as key only */
+						size_t l = strlen(patterns_i);
+						if (strncmp(*proc_cmdline_i, patterns_i, l) == 0) {
+							if((*proc_cmdline_i)[l] == 0 || (*proc_cmdline_i)[l] == '=') {
+								found = TRUE;
+							}
+						}
+					}
+					if(found && negative) {
+						nm_utils_error_set (error, NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,
+						                    "device does not satisfy match.kernel-command-line property %s",
+						                    patterns[i]);
+						return FALSE;  /* first negative match */
+					}
+					proc_cmdline_i++;
+				}
+
+				if (pos_patterns == TRUE && found == FALSE) {  /* positive patterns configured but no match */
+					nm_utils_error_set (error, NM_UTILS_ERROR_CONNECTION_AVAILABLE_TEMPORARY,
+					                    "device does not satisfy any match.kernel-command-line property %s...",
+					                    patterns[0]);
+					return FALSE;
+				}
+			}
+		}
 	}
 
 	return TRUE;