[DCCP]: Introduce DCCP_SOCKOPT_PACKET_SIZE

So that applications can set dccp_sock->dccps_pkt_size, that in turn
is used in the CCID3 half connection init routines to set
ccid3hc[tr]x_s and use it in its rate calculations.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 48 insertions, 4 deletions

diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index f4da6561e40c..18a0e69c9dc7 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -205,23 +205,67 @@ int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
 int dccp_setsockopt(struct sock *sk, int level, int optname,
                     char __user *optval, int optlen)
 {
-        dccp_pr_debug("entry\n");
+        struct dccp_sock *dp;
+        int err;
+        int val;
 
         if (level != SOL_DCCP)
                 return ip_setsockopt(sk, level, optname, optval, optlen);
 
-        return -EOPNOTSUPP;
+        if (optlen < sizeof(int))
+                return -EINVAL;
+
+        if (get_user(val, (int __user *)optval))
+                return -EFAULT;
+
+        lock_sock(sk);
+
+        dp = dccp_sk(sk);
+        err = 0;
+
+        switch (optname) {
+        case DCCP_SOCKOPT_PACKET_SIZE:
+                dp->dccps_packet_size = val;
+                break;
+        default:
+                err = -ENOPROTOOPT;
+                break;
+        }
+        
+        release_sock(sk);
+        return err;
 }
 
 int dccp_getsockopt(struct sock *sk, int level, int optname,
                     char __user *optval, int __user *optlen)
 {
-        dccp_pr_debug("entry\n");
+        struct dccp_sock *dp;
+        int val, len;
 
         if (level != SOL_DCCP)
                 return ip_getsockopt(sk, level, optname, optval, optlen);
 
-        return -EOPNOTSUPP;
+        if (get_user(len, optlen))
+                return -EFAULT;
+
+        len = min_t(unsigned int, len, sizeof(int));
+        if (len < 0)
+                return -EINVAL;
+
+        dp = dccp_sk(sk);
+
+        switch (optname) {
+        case DCCP_SOCKOPT_PACKET_SIZE:
+                val = dp->dccps_packet_size;
+                break;
+        default:
+                return -ENOPROTOOPT;
+        }
+
+        if (put_user(len, optlen) || copy_to_user(optval, &val, len))
+                return -EFAULT;
+
+        return 0;
 }
 
 int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,