dhcp/dhclient: parse "interface" statementsbg/dhclient-interface-bgo778430

Until now any "interface" statement was ignored and any enclosed
statement for which we have a special handling was considered, even if
belonging to a different interface. This can cause wrong options to be
set in the generated dhclient configuration.

Change the code to parse "interface" statements and skip the content
if the interface doesn't match.

https://bugzilla.gnome.org/show_bug.cgi?id=778430

2 files changed, 140 insertions, 0 deletions

diff --git a/src/dhcp/nm-dhcp-dhclient-utils.c b/src/dhcp/nm-dhcp-dhclient-utils.c
index f36451b2c3..d63aba4dd2 100644
--- a/src/dhcp/nm-dhcp-dhclient-utils.c
+++ b/src/dhcp/nm-dhcp-dhclient-utils.c
@@ -232,6 +232,39 @@ nm_dhcp_dhclient_get_client_id_from_config_file (const char *path)
 	return NULL;
 }
 
+static gboolean
+read_interface (const char *line, char *interface, guint size)
+{
+	gs_free char *dup = g_strdup (line + NM_STRLEN ("interface"));
+	char *ptr = dup, *end;
+
+	while (g_ascii_isspace (*ptr))
+		ptr++;
+
+	if (*ptr == '"') {
+		ptr++;
+		end = strchr (ptr, '"');
+		if (!end)
+			return FALSE;
+		*end = '\0';
+	} else {
+		end = strchr (ptr, ' ');
+		if (!end)
+			end = strchr (ptr, '{');
+		if (!end)
+			return FALSE;
+		*end = '\0';
+	}
+
+	if (   ptr[0] == '\0'
+	    || strlen (ptr) + 1 > size)
+		return FALSE;
+
+	snprintf (interface, size, "%s", ptr);
+
+	return TRUE;
+}
+
 char *
 nm_dhcp_dhclient_create_config (const char *interface,
                                 gboolean is_ip6,
@@ -258,8 +291,10 @@ nm_dhcp_dhclient_create_config (const char *interface,
 		char **lines, **line;
 		gboolean in_alsoreq = FALSE;
 		gboolean in_req = FALSE;
+		char intf[IFNAMSIZ];
 
 		g_string_append_printf (new_contents, _("# Merged from %s\n\n"), orig_path);
+		intf[0] = '\0';
 
 		lines = g_strsplit_set (orig_contents, "\n\r", 0);
 		for (line = lines; lines && *line; line++) {
@@ -268,6 +303,20 @@ nm_dhcp_dhclient_create_config (const char *interface,
 			if (!strlen (g_strstrip (p)))
 				continue;
 
+			if (   !intf[0]
+			    && g_str_has_prefix (p, "interface")) {
+				if (read_interface (p, intf, sizeof (intf)))
+					continue;
+			}
+
+			if (intf[0] && strchr (p, '}')) {
+				intf[0] = '\0';
+				continue;
+			}
+
+			if (intf[0] && !nm_streq (intf, interface))
+				continue;
+
 			if (!strncmp (p, CLIENTID_TAG, strlen (CLIENTID_TAG))) {
 				/* Override config file "dhcp-client-id" and use one from the connection */
 				if (client_id)
diff --git a/src/dhcp/tests/test-dhcp-dhclient.c b/src/dhcp/tests/test-dhcp-dhclient.c
index f4cf9c9ff2..361c7336be 100644
--- a/src/dhcp/tests/test-dhcp-dhclient.c
+++ b/src/dhcp/tests/test-dhcp-dhclient.c
@@ -744,6 +744,95 @@ test_write_existing_commented_duid (void)
 
 /*****************************************************************************/
 
+static const char *interface1_orig = \
+	"interface \"eth0\" {\n"
+	"	also request my-option;\n"
+	"	initial-delay 5;\n"
+	"}\n"
+	"interface \"eth1\" {\n"
+	"	also request another-option;\n"
+	"	initial-delay 0;\n"
+	"}\n"
+	"\n"
+	"also request yet-another-option;\n";
+
+static const char *interface1_expected = \
+	"# Created by NetworkManager\n"
+	"# Merged from /path/to/dhclient.conf\n"
+	"\n"
+	"initial-delay 5;\n"
+	"\n"
+	"option rfc3442-classless-static-routes code 121 = array of unsigned integer 8;\n"
+	"option ms-classless-static-routes code 249 = array of unsigned integer 8;\n"
+	"option wpad code 252 = string;\n"
+	"\n"
+	"also request my-option;\n"
+	"also request yet-another-option;\n"
+	"also request rfc3442-classless-static-routes;\n"
+	"also request ms-classless-static-routes;\n"
+	"also request static-routes;\n"
+	"also request wpad;\n"
+	"also request ntp-servers;\n"
+	"\n";
+
+static void
+test_interface1 (void)
+{
+	test_config (interface1_orig, interface1_expected,
+	             FALSE, NULL, NULL,
+	             NULL,
+	             NULL,
+	             "eth0",
+	             NULL);
+}
+
+/*****************************************************************************/
+
+static const char *interface2_orig = \
+	"interface eth0 {\n"
+	"	also request my-option;\n"
+	"	initial-delay 5;\n"
+	" }\n"
+	"interface eth1 {\n"
+	"	initial-delay 0;\n"
+	"	request another-option;\n"
+	" } \n"
+	"\n"
+	"also request yet-another-option;\n";
+
+static const char *interface2_expected = \
+	"# Created by NetworkManager\n"
+	"# Merged from /path/to/dhclient.conf\n"
+	"\n"
+	"initial-delay 0;\n"
+	"\n"
+	"option rfc3442-classless-static-routes code 121 = array of unsigned integer 8;\n"
+	"option ms-classless-static-routes code 249 = array of unsigned integer 8;\n"
+	"option wpad code 252 = string;\n"
+	"\n"
+	"request; # override dhclient defaults\n"
+	"also request another-option;\n"
+	"also request yet-another-option;\n"
+	"also request rfc3442-classless-static-routes;\n"
+	"also request ms-classless-static-routes;\n"
+	"also request static-routes;\n"
+	"also request wpad;\n"
+	"also request ntp-servers;\n"
+	"\n";
+
+static void
+test_interface2 (void)
+{
+	test_config (interface2_orig, interface2_expected,
+	             FALSE, NULL, NULL,
+	             NULL,
+	             NULL,
+	             "eth1",
+	             NULL);
+}
+
+/*****************************************************************************/
+
 static void
 test_read_lease_ip4_config_basic (void)
 {
@@ -891,6 +980,8 @@ main (int argc, char **argv)
 	g_test_add_func ("/dhcp/dhclient/existing_alsoreq", test_existing_alsoreq);
 	g_test_add_func ("/dhcp/dhclient/existing_multiline_alsoreq", test_existing_multiline_alsoreq);
 	g_test_add_func ("/dhcp/dhclient/duids", test_duids);
+	g_test_add_func ("/dhcp/dhclient/interface/1", test_interface1);
+	g_test_add_func ("/dhcp/dhclient/interface/2", test_interface2);
 
 	g_test_add_func ("/dhcp/dhclient/read_duid_from_leasefile", test_read_duid_from_leasefile);
 	g_test_add_func ("/dhcp/dhclient/read_commented_duid_from_leasefile", test_read_commented_duid_from_leasefile);