rtnl/ipv6: add support of RTM_GETNETCONF

This message allows to get the devconf for an interface.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 0c57a8f6771510d078d9e9f288966b458291a0bc..8f0b12a67131a54c5665fdb1e1a5cb7aaea90bf3 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -466,7 +466,8 @@ static int inet6_netconf_msgsize_devconf(int type)
        int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
                    + nla_total_size(4);        /* NETCONFA_IFINDEX */
 
-       if (type == NETCONFA_FORWARDING)
+       /* type -1 is used for ALL */
+       if (type == -1 || type == NETCONFA_FORWARDING)
                size += nla_total_size(4);
 
        return size;
@@ -491,7 +492,8 @@ static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
        if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
                goto nla_put_failure;
 
-       if (type == NETCONFA_FORWARDING &&
+       /* type -1 is used for ALL */
+       if ((type == -1 || type == NETCONFA_FORWARDING) &&
            nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
                goto nla_put_failure;
 
@@ -527,6 +529,73 @@ errout:
                rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
 }
 
+static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
+       [NETCONFA_IFINDEX]      = { .len = sizeof(int) },
+       [NETCONFA_FORWARDING]   = { .len = sizeof(int) },
+};
+
+static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
+                                    struct nlmsghdr *nlh,
+                                    void *arg)
+{
+       struct net *net = sock_net(in_skb->sk);
+       struct nlattr *tb[NETCONFA_MAX+1];
+       struct netconfmsg *ncm;
+       struct sk_buff *skb;
+       struct ipv6_devconf *devconf;
+       struct inet6_dev *in6_dev;
+       struct net_device *dev;
+       int ifindex;
+       int err;
+
+       err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
+                         devconf_ipv6_policy);
+       if (err < 0)
+               goto errout;
+
+       err = EINVAL;
+       if (!tb[NETCONFA_IFINDEX])
+               goto errout;
+
+       ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
+       switch (ifindex) {
+       case NETCONFA_IFINDEX_ALL:
+               devconf = net->ipv6.devconf_all;
+               break;
+       case NETCONFA_IFINDEX_DEFAULT:
+               devconf = net->ipv6.devconf_dflt;
+               break;
+       default:
+               dev = __dev_get_by_index(net, ifindex);
+               if (dev == NULL)
+                       goto errout;
+               in6_dev = __in6_dev_get(dev);
+               if (in6_dev == NULL)
+                       goto errout;
+               devconf = &in6_dev->cnf;
+               break;
+       }
+
+       err = -ENOBUFS;
+       skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
+       if (skb == NULL)
+               goto errout;
+
+       err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
+                                        NETLINK_CB(in_skb).portid,
+                                        nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
+                                        -1);
+       if (err < 0) {
+               /* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
+               WARN_ON(err == -EMSGSIZE);
+               kfree_skb(skb);
+               goto errout;
+       }
+       err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
+errout:
+       return err;
+}
+
 #ifdef CONFIG_SYSCTL
 static void dev_forward_change(struct inet6_dev *idev)
 {
@@ -4861,6 +4930,8 @@ int __init addrconf_init(void)
                        inet6_dump_ifmcaddr, NULL);
        __rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
                        inet6_dump_ifacaddr, NULL);
+       __rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
+                       NULL, NULL);
 
        ipv6_addr_label_rtnl_register();