sctp: add support for snd flag SCTP_SENDALL process in sendmsg

This patch is to add support for snd flag SCTP_SENDALL process
in sendmsg, as described in section 5.3.4 of RFC6458.

With this flag, you can send the same data to all the asocs of
this sk once.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index a1bc3509803306a5d3a314a53c7dba922fe1eb10..e94b6d297ad9a4be19715199270dffb9b77da49d 100644 (file)
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -284,6 +284,8 @@ enum sctp_sinfo_flags {
        SCTP_ADDR_OVER          = (1 << 1), /* Override the primary destination. */
        SCTP_ABORT              = (1 << 2), /* Send an ABORT message to the peer. */
        SCTP_SACK_IMMEDIATELY   = (1 << 3), /* SACK should be sent without delay. */
+       /* 2 bits here have been used by SCTP_PR_SCTP_MASK */
+       SCTP_SENDALL            = (1 << 6),
        SCTP_NOTIFICATION       = MSG_NOTIFICATION, /* Next message is not user msg but notification. */
        SCTP_EOF                = MSG_FIN,  /* Initiate graceful shutdown process. */
 };

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 067b57a330b129e2ce7e8218e44193d3e5e8561f..7d3476a4860d47958e7b5b0b3d4c69cb7306affd 100644 (file)
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1820,6 +1820,10 @@ static int sctp_sendmsg_check_sflags(struct sctp_association *asoc,
        if (sctp_state(asoc, CLOSED) && sctp_style(sk, TCP))
                return -EPIPE;
 
+       if ((sflags & SCTP_SENDALL) && sctp_style(sk, UDP) &&
+           !sctp_state(asoc, ESTABLISHED))
+               return 0;
+
        if (sflags & SCTP_EOF) {
                pr_debug("%s: shutting down association:%p\n", __func__, asoc);
                sctp_primitive_SHUTDOWN(net, asoc, NULL);
@@ -2007,6 +2011,29 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
 
        lock_sock(sk);
 
+       /* SCTP_SENDALL process */
+       if ((sflags & SCTP_SENDALL) && sctp_style(sk, UDP)) {
+               list_for_each_entry(asoc, &ep->asocs, asocs) {
+                       err = sctp_sendmsg_check_sflags(asoc, sflags, msg,
+                                                       msg_len);
+                       if (err == 0)
+                               continue;
+                       if (err < 0)
+                               goto out_unlock;
+
+                       sctp_sendmsg_update_sinfo(asoc, sinfo, &cmsgs);
+
+                       err = sctp_sendmsg_to_asoc(asoc, msg, msg_len,
+                                                  NULL, sinfo);
+                       if (err < 0)
+                               goto out_unlock;
+
+                       iov_iter_revert(&msg->msg_iter, err);
+               }
+
+               goto out_unlock;
+       }
+
        /* Get and check or create asoc */
        if (daddr) {
                asoc = sctp_endpoint_lookup_assoc(ep, daddr, &transport);
@@ -7792,8 +7819,8 @@ static int sctp_msghdr_parse(const struct msghdr *msg, struct sctp_cmsgs *cmsgs)
 
                        if (cmsgs->srinfo->sinfo_flags &
                            ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
-                             SCTP_SACK_IMMEDIATELY | SCTP_PR_SCTP_MASK |
-                             SCTP_ABORT | SCTP_EOF))
+                             SCTP_SACK_IMMEDIATELY | SCTP_SENDALL |
+                             SCTP_PR_SCTP_MASK | SCTP_ABORT | SCTP_EOF))
                                return -EINVAL;
                        break;
 
@@ -7816,8 +7843,8 @@ static int sctp_msghdr_parse(const struct msghdr *msg, struct sctp_cmsgs *cmsgs)
 
                        if (cmsgs->sinfo->snd_flags &
                            ~(SCTP_UNORDERED | SCTP_ADDR_OVER |
-                             SCTP_SACK_IMMEDIATELY | SCTP_PR_SCTP_MASK |
-                             SCTP_ABORT | SCTP_EOF))
+                             SCTP_SACK_IMMEDIATELY | SCTP_SENDALL |
+                             SCTP_PR_SCTP_MASK | SCTP_ABORT | SCTP_EOF))
                                return -EINVAL;
                        break;
                case SCTP_PRINFO: