sctp: support non-blocking version of the new sctp_connectx() API

Prior implementation of the new sctp_connectx() call that returns
an association ID did not work correctly on non-blocking socket.
This is because we could not return both a EINPROGRESS error and
an association id.  This is a new implementation that supports this.

Originally from Ivan Skytte Jørgensen <isj-sctp@i1.dk

Signed-off-by: Ivan Skytte Jørgensen <isj-sctp@i1.dk
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

diff --git a/include/net/sctp/user.h b/include/net/sctp/user.h
index b259fc5798fb2f909fda0cc80be04d906b3879cc..1580c04f68bc20df0ba36955caf7d5f5fff5538d 100644 (file)
--- a/include/net/sctp/user.h
+++ b/include/net/sctp/user.h
@@ -147,6 +147,8 @@ enum sctp_optname {
 #define SCTP_GET_LOCAL_ADDRS   SCTP_GET_LOCAL_ADDRS
        SCTP_SOCKOPT_CONNECTX, /* CONNECTX requests. */
 #define SCTP_SOCKOPT_CONNECTX  SCTP_SOCKOPT_CONNECTX
+       SCTP_SOCKOPT_CONNECTX3, /* CONNECTX requests. (new implementation) */
+#define SCTP_SOCKOPT_CONNECTX3 SCTP_SOCKOPT_CONNECTX3
 };
 
 /*

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 39f5166ae7af3429f0a590b51561869b21d70e7e..525864bf4f07d6caef08520d195053d5b0e25edf 100644 (file)
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -1470,6 +1470,10 @@ int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
 {
        int assoc_id;
        int error = 0;
+
+       /* If the id is already assigned, keep it. */
+       if (asoc->assoc_id)
+               return error;
 retry:
        if (unlikely(!idr_pre_get(&sctp_assocs_id, gfp)))
                return -ENOMEM;

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 5fb3a8c9792e741dac08902a0f8b7cc1f43dc872..7c3dfd2d94898fa84e818c3c454fa39b118678ae 100644 (file)
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1100,6 +1100,15 @@ static int __sctp_connect(struct sock* sk,
                goto out_free;
        }
 
+       /* In case the user of sctp_connectx() wants an association
+        * id back, assign one now.
+        */
+       if (assoc_id) {
+               err = sctp_assoc_set_id(asoc, GFP_KERNEL);
+               if (err < 0)
+                       goto out_free;
+       }
+
        err = sctp_primitive_ASSOCIATE(asoc, NULL);
        if (err < 0) {
                goto out_free;
@@ -1120,7 +1129,7 @@ static int __sctp_connect(struct sock* sk,
        timeo = sock_sndtimeo(sk, f_flags & O_NONBLOCK);
 
        err = sctp_wait_for_connect(asoc, &timeo);
-       if (!err && assoc_id)
+       if ((err == 0 || err == -EINPROGRESS) && assoc_id)
                *assoc_id = asoc->assoc_id;
 
        /* Don't free association on exit. */
@@ -1264,6 +1273,34 @@ SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
                return assoc_id;
 }
 
+/*
+ * New (hopefully final) interface for the API.  The option buffer is used
+ * both for the returned association id and the addresses.
+ */
+SCTP_STATIC int sctp_getsockopt_connectx3(struct sock* sk, int len,
+                                       char __user *optval,
+                                       int __user *optlen)
+{
+       sctp_assoc_t assoc_id = 0;
+       int err = 0;
+
+       if (len < sizeof(assoc_id))
+               return -EINVAL;
+
+       err = __sctp_setsockopt_connectx(sk,
+                       (struct sockaddr __user *)(optval + sizeof(assoc_id)),
+                       len - sizeof(assoc_id), &assoc_id);
+
+       if (err == 0 || err == -EINPROGRESS) {
+               if (copy_to_user(optval, &assoc_id, sizeof(assoc_id)))
+                       return -EFAULT;
+               if (put_user(sizeof(assoc_id), optlen))
+                       return -EFAULT;
+       }
+
+       return err;
+}
+
 /* API 3.1.4 close() - UDP Style Syntax
  * Applications use close() to perform graceful shutdown (as described in
  * Section 10.1 of [SCTP]) on ALL the associations currently represented
@@ -5578,6 +5615,9 @@ SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
                retval = sctp_getsockopt_local_addrs(sk, len, optval,
                                                     optlen);
                break;
+       case SCTP_SOCKOPT_CONNECTX3:
+               retval = sctp_getsockopt_connectx3(sk, len, optval, optlen);
+               break;
        case SCTP_DEFAULT_SEND_PARAM:
                retval = sctp_getsockopt_default_send_param(sk, len,
                                                            optval, optlen);