1 files changed, 71 insertions, 0 deletions

diff --git a/net/dcb/dcbnl.c b/net/dcb/dcbnl.c
index 656c7c75b192..5520e431b072 100644
--- a/net/dcb/dcbnl.c
+++ b/net/dcb/dcbnl.c
@@ -196,6 +196,34 @@ static const struct nla_policy dcbnl_featcfg_nest[DCB_FEATCFG_ATTR_MAX + 1] = {
 static LIST_HEAD(dcb_app_list);
 static DEFINE_SPINLOCK(dcb_lock);
 
+static struct sk_buff *dcbnl_newmsg(int type, u8 cmd, u32 port, u32 seq,
+                                    u32 flags, struct nlmsghdr **nlhp)
+{
+        struct sk_buff *skb;
+        struct dcbmsg *dcb;
+        struct nlmsghdr *nlh;
+
+        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+        if (!skb)
+                return NULL;
+
+        nlh = nlmsg_put(skb, port, seq, type, sizeof(*dcb), flags);
+        if (!nlh) {
+                /* header should always fit, allocation must be buggy */
+                BUG();
+        }
+
+        dcb = nlmsg_data(nlh);
+        dcb->dcb_family = AF_UNSPEC;
+        dcb->cmd = cmd;
+        dcb->dcb_pad = 0;
+
+        if (nlhp)
+                *nlhp = nlh;
+
+        return skb;
+}
+
 /* standard netlink reply call */
 static int dcbnl_reply(u8 value, u8 event, u8 cmd, u8 attr, u32 pid,
                        u32 seq, u16 flags)
@@ -1922,6 +1950,19 @@ static int dcbnl_cee_get(struct net_device *netdev, struct nlattr **tb,
         return err;
 }
 
+struct reply_func {
+        /* reply netlink message type */
+        int     type;
+
+        /* function to fill message contents */
+        int   (*cb)(struct net_device *, struct nlmsghdr *, u32,
+                    struct nlattr **, struct sk_buff *);
+};
+
+static const struct reply_func reply_funcs[DCB_CMD_MAX+1] = {
+        /* FIXME: add reply defs */
+};
+
 static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
         struct net *net = sock_net(skb->sk);
@@ -1930,6 +1971,9 @@ static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
         struct nlattr *tb[DCB_ATTR_MAX + 1];
         u32 pid = skb ? NETLINK_CB(skb).pid : 0;
         int ret = -EINVAL;
+        struct sk_buff *reply_skb;
+        struct nlmsghdr *reply_nlh;
+        const struct reply_func *fn;
 
         if (!net_eq(net, &init_net))
                 return -EINVAL;
@@ -1939,6 +1983,14 @@ static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
         if (ret < 0)
                 return ret;
 
+        if (dcb->cmd > DCB_CMD_MAX)
+                return -EINVAL;
+
+        /* check if a reply function has been defined for the command */
+        fn = &reply_funcs[dcb->cmd];
+        if (!fn->cb)
+                return -EOPNOTSUPP;
+
         if (!tb[DCB_ATTR_IFNAME])
                 return -EINVAL;
 
@@ -1949,6 +2001,25 @@ static int dcb_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
         if (!netdev->dcbnl_ops)
                 goto errout;
 
+        reply_skb = dcbnl_newmsg(fn->type, dcb->cmd, pid, nlh->nlmsg_seq,
+                                 nlh->nlmsg_flags, &reply_nlh);
+        if (!reply_skb) {
+                ret = -ENOBUFS;
+                goto out;
+        }
+
+        ret = fn->cb(netdev, nlh, nlh->nlmsg_seq, tb, reply_skb);
+        if (ret < 0) {
+                nlmsg_free(reply_skb);
+                goto out;
+        }
+
+        nlmsg_end(reply_skb, reply_nlh);
+
+        ret = rtnl_unicast(reply_skb, &init_net, pid);
+        if (ret)
+                goto out;
+
         switch (dcb->cmd) {
         case DCB_CMD_GSTATE:
                 ret = dcbnl_getstate(netdev, tb, pid, nlh->nlmsg_seq,