Add a control socket so that interfaces can be dynamically re-set.

This requires the event loop argument being changed to void *
so we can send arguments other than an interface.

1 files changed, 163 insertions, 0 deletions

diff --git a/control.c b/control.c
new file mode 100644
index 00000000..6b0f1a19
--- /dev/null
+++ b/control.c
@@ -0,0 +1,163 @@
+/* 
+ * dhcpcd - DHCP client daemon
+ * Copyright 2006-2008 Roy Marples <roy@marples.name>
+ * All rights reserved
+
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/stat.h>
+#include <sys/un.h>
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "config.h"
+#include "common.h"
+#include "control.h"
+#include "eloop.h"
+#include "dhcpcd.h"
+
+static int fd = -1;
+struct sockaddr_un sun;
+static char buffer[1024];
+static char *argvp[255];
+
+static void
+handle_control_data(void *arg)
+{
+	ssize_t bytes;
+	int argc, s = (int)arg;
+	char *e, *p;
+	char **ap;
+
+	for (;;) {
+		bytes = read(s, buffer, sizeof(buffer));
+		if (bytes == -1 || bytes == 0) {
+			close(s);
+			delete_event(s);
+			return;
+		}
+		p = buffer;
+		e = buffer + bytes;
+		argc = 0;
+		ap = argvp;
+		while (p < e && (size_t)argc < sizeof(argvp)) {
+			argc++;
+			*ap++ = p;
+			p += strlen(p) + 1;
+		}
+		handle_args(argc, argvp);
+	}
+}
+
+static void
+handle_control(_unused void *arg)
+{
+	struct sockaddr_un run;
+	socklen_t len;
+	int s;
+
+	len = sizeof(run);
+	if ((s = accept(fd, (struct sockaddr *)&run, &len)) == -1)
+		return;
+	add_event(s, handle_control_data, (void *)s);
+}
+
+static int
+make_sock(void)
+{
+	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
+		return -1;
+	memset(&sun, 0, sizeof(sun));
+	sun.sun_family = AF_UNIX;
+	strlcpy(sun.sun_path, CONTROLSOCKET, sizeof(sun.sun_path));
+	return sizeof(sun.sun_family) + strlen(sun.sun_path) + 1;
+}
+
+int
+start_control(void)
+{
+	int len;
+
+	if ((len = make_sock()) == -1)
+		return -1;
+	unlink(CONTROLSOCKET);
+	if (bind(fd, (struct sockaddr *)&sun, len) == -1 ||
+	    chmod(CONTROLSOCKET, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP) == -1 ||
+	    set_cloexec(fd) == -1 ||
+	    set_nonblock(fd) == -1 ||
+	    listen(fd, 0) == -1)
+	{
+		close(fd);
+		return -1;
+	}
+	add_event(fd, handle_control, NULL);
+	return fd;
+}
+
+int
+stop_control(void)
+{
+	int retval = 0;
+	if (close(fd) == -1)
+		retval = 1;
+	if (unlink(CONTROLSOCKET) == -1)
+		retval = -1;
+	return retval;
+}
+
+int
+open_control(void)
+{
+	int len;
+
+	if ((len = make_sock()) == -1)
+		return -1;
+	return connect(fd, (struct sockaddr *)&sun, len);
+}
+
+int
+send_control(int argc, char * const *argv)
+{
+	char *p = buffer;
+	int i;
+	size_t len;
+
+	if (argc > 255) {
+		errno = ENOBUFS;
+		return -1;
+	}
+	for (i = 0; i < argc; i++) {
+		len = strlen(argv[i]) + 1;
+		if ((p - buffer) + len > sizeof(buffer)) {
+			errno = ENOBUFS;
+			return -1;
+		}
+		memcpy(p, argv[i], len);
+		p += len;
+	}
+	return write(fd, buffer, p - buffer);
+}