sctp: Follow security requirement of responding with 1 packet

[linux-2.6] / net / sctp / socket.c

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 66985871401be47747946eb1e1d8e13d207fd229..f98650cc48d8bf0f3e0806177305b9013cb05312 100644 (file)
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -956,7 +956,8 @@ out:
  */
 static int __sctp_connect(struct sock* sk,
                          struct sockaddr *kaddrs,
-                         int addrs_size)
+                         int addrs_size,
+                         sctp_assoc_t *assoc_id)
 {
        struct sctp_sock *sp;
        struct sctp_endpoint *ep;
@@ -1111,6 +1112,8 @@ 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)
+               *assoc_id = asoc->assoc_id;
 
        /* Don't free association on exit. */
        asoc = NULL;
@@ -1128,7 +1131,8 @@ out_free:
 /* Helper for tunneling sctp_connectx() requests through sctp_setsockopt()
  *
  * API 8.9
- * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt);
+ * int sctp_connectx(int sd, struct sockaddr *addrs, int addrcnt,
+ *                     sctp_assoc_t *asoc);
  *
  * If sd is an IPv4 socket, the addresses passed must be IPv4 addresses.
  * If the sd is an IPv6 socket, the addresses passed can either be IPv4
@@ -1144,8 +1148,10 @@ out_free:
  * representation is termed a "packed array" of addresses). The caller
  * specifies the number of addresses in the array with addrcnt.
  *
- * On success, sctp_connectx() returns 0. On failure, sctp_connectx() returns
- * -1, and sets errno to the appropriate error code.
+ * On success, sctp_connectx() returns 0. It also sets the assoc_id to
+ * the association id of the new association.  On failure, sctp_connectx()
+ * returns -1, and sets errno to the appropriate error code.  The assoc_id
+ * is not touched by the kernel.
  *
  * For SCTP, the port given in each socket address must be the same, or
  * sctp_connectx() will fail, setting errno to EINVAL.
@@ -1182,11 +1188,12 @@ out_free:
  * addrs     The pointer to the addresses in user land
  * addrssize Size of the addrs buffer
  *
- * Returns 0 if ok, <0 errno code on error.
+ * Returns >=0 if ok, <0 errno code on error.
  */
-SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
+SCTP_STATIC int __sctp_setsockopt_connectx(struct sock* sk,
                                      struct sockaddr __user *addrs,
-                                     int addrs_size)
+                                     int addrs_size,
+                                     sctp_assoc_t *assoc_id)
 {
        int err = 0;
        struct sockaddr *kaddrs;
@@ -1209,13 +1216,46 @@ SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
        if (__copy_from_user(kaddrs, addrs, addrs_size)) {
                err = -EFAULT;
        } else {
-               err = __sctp_connect(sk, kaddrs, addrs_size);
+               err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id);
        }
 
        kfree(kaddrs);
+
        return err;
 }
 
+/*
+ * This is an older interface.  It's kept for backward compatibility
+ * to the option that doesn't provide association id.
+ */
+SCTP_STATIC int sctp_setsockopt_connectx_old(struct sock* sk,
+                                     struct sockaddr __user *addrs,
+                                     int addrs_size)
+{
+       return __sctp_setsockopt_connectx(sk, addrs, addrs_size, NULL);
+}
+
+/*
+ * New interface for the API.  The since the API is done with a socket
+ * option, to make it simple we feed back the association id is as a return
+ * indication to the call.  Error is always negative and association id is
+ * always positive.
+ */
+SCTP_STATIC int sctp_setsockopt_connectx(struct sock* sk,
+                                     struct sockaddr __user *addrs,
+                                     int addrs_size)
+{
+       sctp_assoc_t assoc_id = 0;
+       int err = 0;
+
+       err = __sctp_setsockopt_connectx(sk, addrs, addrs_size, &assoc_id);
+
+       if (err)
+               return err;
+       else
+               return assoc_id;
+}
+
 /* 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
@@ -2431,7 +2471,7 @@ static int sctp_setsockopt_delayed_ack(struct sock *sk,
                                        (trans->param_flags & ~SPP_SACKDELAY) |
                                        SPP_SACKDELAY_ENABLE;
                        }
-                       if (params.sack_delay == 1) {
+                       if (params.sack_freq == 1) {
                                trans->param_flags =
                                        (trans->param_flags & ~SPP_SACKDELAY) |
                                        SPP_SACKDELAY_DISABLE;
@@ -3206,10 +3246,18 @@ SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
                                               optlen, SCTP_BINDX_REM_ADDR);
                break;
 
+       case SCTP_SOCKOPT_CONNECTX_OLD:
+               /* 'optlen' is the size of the addresses buffer. */
+               retval = sctp_setsockopt_connectx_old(sk,
+                                           (struct sockaddr __user *)optval,
+                                           optlen);
+               break;
+
        case SCTP_SOCKOPT_CONNECTX:
                /* 'optlen' is the size of the addresses buffer. */
-               retval = sctp_setsockopt_connectx(sk, (struct sockaddr __user *)optval,
-                                              optlen);
+               retval = sctp_setsockopt_connectx(sk,
+                                           (struct sockaddr __user *)optval,
+                                           optlen);
                break;
 
        case SCTP_DISABLE_FRAGMENTS:
@@ -3336,7 +3384,7 @@ SCTP_STATIC int sctp_connect(struct sock *sk, struct sockaddr *addr,
                /* Pass correct addr len to common routine (so it knows there
                 * is only one address being passed.
                 */
-               err = __sctp_connect(sk, addr, af->sockaddr_len);
+               err = __sctp_connect(sk, addr, af->sockaddr_len, NULL);
        }
 
        sctp_release_sock(sk);
@@ -3488,7 +3536,7 @@ SCTP_STATIC int sctp_init_sock(struct sock *sk)
        sp->pathmaxrxt  = sctp_max_retrans_path;
        sp->pathmtu     = 0; // allow default discovery
        sp->sackdelay   = sctp_sack_timeout;
-       sp->sackfreq    = 3;
+       sp->sackfreq    = 2;
        sp->param_flags = SPP_HB_ENABLE |
                          SPP_PMTUD_ENABLE |
                          SPP_SACKDELAY_ENABLE;
@@ -3540,7 +3588,7 @@ SCTP_STATIC int sctp_init_sock(struct sock *sk)
 }
 
 /* Cleanup any SCTP per socket resources.  */
-SCTP_STATIC int sctp_destroy_sock(struct sock *sk)
+SCTP_STATIC void sctp_destroy_sock(struct sock *sk)
 {
        struct sctp_endpoint *ep;
 
@@ -3550,7 +3598,6 @@ SCTP_STATIC int sctp_destroy_sock(struct sock *sk)
        ep = sctp_sk(sk)->ep;
        sctp_endpoint_free(ep);
        atomic_dec(&sctp_sockets_allocated);
-       return 0;
 }
 
 /* API 4.1.7 shutdown() - TCP Style Syntax