IPv6: Add 'autoconf' and 'disable_ipv6' module parameters
Add 'autoconf' and 'disable_ipv6' parameters to the IPv6 module.
The first controls if IPv6 addresses are autoconfigured from
prefixes received in Router Advertisements. The IPv6 loopback
(::1) and link-local addresses are still configured.
The second controls if IPv6 addresses are desired at all. No
IPv6 addresses will be added to any interfaces.
Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 3ffd233..8be7623 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -1057,6 +1057,13 @@
address.
Default: FALSE (enable IPv6 operation)
+ When this value is changed from 1 to 0 (IPv6 is being enabled),
+ it will dynamically create a link-local address on the given
+ interface and start Duplicate Address Detection, if necessary.
+
+ When this value is changed from 0 to 1 (IPv6 is being disabled),
+ it will dynamically delete all address on the given interface.
+
accept_dad - INTEGER
Whether to accept DAD (Duplicate Address Detection).
0: Disable DAD
diff --git a/Documentation/networking/ipv6.txt b/Documentation/networking/ipv6.txt
index 268e5c1..9fd7e21 100644
--- a/Documentation/networking/ipv6.txt
+++ b/Documentation/networking/ipv6.txt
@@ -33,3 +33,40 @@
A reboot is required to enable IPv6.
+autoconf
+
+ Specifies whether to enable IPv6 address autoconfiguration
+ on all interfaces. This might be used when one does not wish
+ for addresses to be automatically generated from prefixes
+ received in Router Advertisements.
+
+ The possible values and their effects are:
+
+ 0
+ IPv6 address autoconfiguration is disabled on all interfaces.
+
+ Only the IPv6 loopback address (::1) and link-local addresses
+ will be added to interfaces.
+
+ 1
+ IPv6 address autoconfiguration is enabled on all interfaces.
+
+ This is the default value.
+
+disable_ipv6
+
+ Specifies whether to disable IPv6 on all interfaces.
+ This might be used when no IPv6 addresses are desired.
+
+ The possible values and their effects are:
+
+ 0
+ IPv6 is enabled on all interfaces.
+
+ This is the default value.
+
+ 1
+ IPv6 is disabled on all interfaces.
+
+ No IPv6 addresses will be added to interfaces.
+
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 476d946..c662efa 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -169,6 +169,12 @@
__s32 accept_dad;
void *sysctl;
};
+
+struct ipv6_params {
+ __s32 disable_ipv6;
+ __s32 autoconf;
+};
+extern struct ipv6_params ipv6_defaults;
#endif
/* index values for the variables in ipv6_devconf */
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 31938e5..c348837 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -591,7 +591,6 @@
{
struct inet6_ifaddr *ifa = NULL;
struct rt6_info *rt;
- struct net *net = dev_net(idev->dev);
int hash;
int err = 0;
int addr_type = ipv6_addr_type(addr);
@@ -608,7 +607,7 @@
goto out2;
}
- if (idev->cnf.disable_ipv6 || net->ipv6.devconf_all->disable_ipv6) {
+ if (idev->cnf.disable_ipv6) {
err = -EACCES;
goto out2;
}
@@ -1752,6 +1751,7 @@
__u32 prefered_lft;
int addr_type;
struct inet6_dev *in6_dev;
+ struct net *net = dev_net(dev);
pinfo = (struct prefix_info *) opt;
@@ -1809,7 +1809,7 @@
if (addrconf_finite_timeout(rt_expires))
rt_expires *= HZ;
- rt = rt6_lookup(dev_net(dev), &pinfo->prefix, NULL,
+ rt = rt6_lookup(net, &pinfo->prefix, NULL,
dev->ifindex, 1);
if (rt && addrconf_is_prefix_route(rt)) {
@@ -1846,7 +1846,6 @@
struct inet6_ifaddr * ifp;
struct in6_addr addr;
int create = 0, update_lft = 0;
- struct net *net = dev_net(dev);
if (pinfo->prefix_len == 64) {
memcpy(&addr, &pinfo->prefix, 8);
@@ -3988,6 +3987,75 @@
return addrconf_fixup_forwarding(table, valp, val);
}
+static void dev_disable_change(struct inet6_dev *idev)
+{
+ if (!idev || !idev->dev)
+ return;
+
+ if (idev->cnf.disable_ipv6)
+ addrconf_notify(NULL, NETDEV_DOWN, idev->dev);
+ else
+ addrconf_notify(NULL, NETDEV_UP, idev->dev);
+}
+
+static void addrconf_disable_change(struct net *net, __s32 newf)
+{
+ struct net_device *dev;
+ struct inet6_dev *idev;
+
+ read_lock(&dev_base_lock);
+ for_each_netdev(net, dev) {
+ rcu_read_lock();
+ idev = __in6_dev_get(dev);
+ if (idev) {
+ int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
+ idev->cnf.disable_ipv6 = newf;
+ if (changed)
+ dev_disable_change(idev);
+ }
+ rcu_read_unlock();
+ }
+ read_unlock(&dev_base_lock);
+}
+
+static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int old)
+{
+ struct net *net;
+
+ net = (struct net *)table->extra2;
+
+ if (p == &net->ipv6.devconf_dflt->disable_ipv6)
+ return 0;
+
+ if (!rtnl_trylock())
+ return restart_syscall();
+
+ if (p == &net->ipv6.devconf_all->disable_ipv6) {
+ __s32 newf = net->ipv6.devconf_all->disable_ipv6;
+ net->ipv6.devconf_dflt->disable_ipv6 = newf;
+ addrconf_disable_change(net, newf);
+ } else if ((!*p) ^ (!old))
+ dev_disable_change((struct inet6_dev *)table->extra1);
+
+ rtnl_unlock();
+ return 0;
+}
+
+static
+int addrconf_sysctl_disable(ctl_table *ctl, int write, struct file * filp,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ int *valp = ctl->data;
+ int val = *valp;
+ int ret;
+
+ ret = proc_dointvec(ctl, write, filp, buffer, lenp, ppos);
+
+ if (write)
+ ret = addrconf_disable_ipv6(ctl, valp, val);
+ return ret;
+}
+
static struct addrconf_sysctl_table
{
struct ctl_table_header *sysctl_header;
@@ -4225,7 +4293,8 @@
.data = &ipv6_devconf.disable_ipv6,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = addrconf_sysctl_disable,
+ .strategy = sysctl_intvec,
},
{
.ctl_name = CTL_UNNUMBERED,
@@ -4346,6 +4415,10 @@
dflt = kmemdup(dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
if (dflt == NULL)
goto err_alloc_dflt;
+ } else {
+ /* these will be inherited by all namespaces */
+ dflt->autoconf = ipv6_defaults.autoconf;
+ dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
}
net->ipv6.devconf_all = all;
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index b6215be..85b3d00 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -72,9 +72,21 @@
static struct list_head inetsw6[SOCK_MAX];
static DEFINE_SPINLOCK(inetsw6_lock);
-static int disable_ipv6 = 0;
-module_param_named(disable, disable_ipv6, int, 0);
-MODULE_PARM_DESC(disable, "Disable IPv6 such that it is non-functional");
+struct ipv6_params ipv6_defaults = {
+ .disable_ipv6 = 0,
+ .autoconf = 1,
+};
+
+static int disable_ipv6_mod = 0;
+
+module_param_named(disable, disable_ipv6_mod, int, 0444);
+MODULE_PARM_DESC(disable, "Disable IPv6 module such that it is non-functional");
+
+module_param_named(disable_ipv6, ipv6_defaults.disable_ipv6, int, 0444);
+MODULE_PARM_DESC(disable_ipv6, "Disable IPv6 on all interfaces");
+
+module_param_named(autoconf, ipv6_defaults.autoconf, int, 0444);
+MODULE_PARM_DESC(autoconf, "Enable IPv6 address autoconfiguration on all interfaces");
static __inline__ struct ipv6_pinfo *inet6_sk_generic(struct sock *sk)
{
@@ -1038,7 +1050,7 @@
for(r = &inetsw6[0]; r < &inetsw6[SOCK_MAX]; ++r)
INIT_LIST_HEAD(r);
- if (disable_ipv6) {
+ if (disable_ipv6_mod) {
printk(KERN_INFO
"IPv6: Loaded, but administratively disabled, "
"reboot required to enable\n");
@@ -1227,7 +1239,7 @@
static void __exit inet6_exit(void)
{
- if (disable_ipv6)
+ if (disable_ipv6_mod)
return;
/* First of all disallow new sockets creation. */
