[CRIU] [PATCH 4/4] netdevconf: restore network devices config options

[Pavel Tikhomirov]

Signed-off-by: Pavel Tikhomirov <ptikhomirov at parallels.com>
---
 net.c | 89 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)

diff --git a/net.c b/net.c
index 5619fe4..0631b9f 100644
--- a/net.c
+++ b/net.c
@@ -646,6 +646,93 @@ static inline int restore_iptables(int pid)
 	return ret;
 }
 
+static int restore_one_option(char *option, char *path, void *data)
+{
+	int ret;
+	int val;
+	FILE *fp;
+	NetDeviceIpv4ConfEntry *netdev = data;
+
+	ret = get_opt_index(option);
+	if (ret < 0)
+		return -1;
+
+	val = netdev->data[ret];
+
+	ret = access(path, W_OK);
+	if (ret < 0) {
+		/*
+		 * If don't have access, at least check option don't change
+		 * mainly it's made for mc_forwarding option: it is write protected
+		 */
+		int tmp;
+		pr_debug("%s option is write protected", option);
+		fp = fopen(path, "r");
+		if (fp == NULL) {
+			pr_perror("fopen");
+			return -1;
+		}
+
+		ret = fscanf(fp, "%d", &tmp);
+		if (ret < 0) {
+			pr_perror("fscanf");
+			return -1;
+		}
+
+		if (val != tmp) {
+			pr_err("Network device ipv4 config option %s corrupted", option);
+			return -1;
+		}
+		return 0;
+	}
+
+	fp = fopen(path, "w");
+	if (fp == NULL) {
+		pr_perror("fopen");
+		return -1;
+	}
+
+	ret = fprintf(fp, "%d", val);
+	if (ret < 0) {
+		pr_perror("fprintf");
+		return -1;
+	}
+
+	fclose(fp);
+	return 0;
+}
+
+static int restore_net_devs_conf(int pid)
+{
+	int fd;
+	NetDeviceIpv4ConfEntry *netdev;
+
+	fd = open_image(CR_FD_NETDEV_CONF, O_RSTR, pid);
+	if (fd < 0) {
+		pr_perror("open_image");
+		return -1;
+	}
+
+	while (1) {
+		int ret;
+		char path[PATH_MAX];
+
+		ret = pb_read_one_eof(fd, &netdev, PB_NETDEV_CONF);
+		if (ret <= 0)
+			break;
+
+		snprintf(path, sizeof(path), "%s/%s", NET_IPV4_CONF_DIR, netdev->dev_name);
+		ret = for_each_entry_do(path, restore_one_option, (void*)netdev);
+		if (ret < 0)
+			return -1;
+
+		net_device_ipv4_conf_entry__free_unpacked(netdev, NULL);
+	}
+
+	close(fd);
+	return 0;
+}
+
 static int mount_ns_sysfs(void)
 {
 	char sys_mount[] = "crtools-sys.XXXXXX";
@@ -727,6 +814,8 @@ int prepare_net_ns(int pid)
 		ret = restore_route(pid);
 	if (!ret)
 		ret = restore_iptables(pid);
+	if (!ret)
+		ret = restore_net_devs_conf(pid);
 
 	close(ns_fd);
 
-- 
1.9.3