dccp: API to query the current TX/RX CCID

This provides function to query the current TX/RX CCID dynamically,
without reliance on the minisock value, using dynamic information
available in the currently loaded CCID module.

This query function is then used to
 (a) provide the getsockopt part for getting/setting CCIDs via sockopts;
 (b) replace the current test for "which CCID is in use" in probe.c.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 18 insertions, 0 deletions

diff --git a/net/dccp/ccid.h b/net/dccp/ccid.h
index 259f5469d7d0..803343aed004 100644
--- a/net/dccp/ccid.h
+++ b/net/dccp/ccid.h
@@ -116,6 +116,24 @@ extern struct ccid *ccid_hc_rx_new(unsigned char id, struct sock *sk,
 extern struct ccid *ccid_hc_tx_new(unsigned char id, struct sock *sk,
                                    gfp_t gfp);
 
+static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp)
+{
+        struct ccid *ccid = dp->dccps_hc_rx_ccid;
+
+        if (ccid == NULL || ccid->ccid_ops == NULL)
+                return -1;
+        return ccid->ccid_ops->ccid_id;
+}
+
+static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp)
+{
+        struct ccid *ccid = dp->dccps_hc_tx_ccid;
+
+        if (ccid == NULL || ccid->ccid_ops == NULL)
+                return -1;
+        return ccid->ccid_ops->ccid_id;
+}
+
 extern void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
 extern void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk);