- use sendmsg instead of sendto for TFO.

git-svn-id: file:///svn/unbound/trunk@3827 be551aaa-1e26-0410-a405-d3ace91eadb9

diff --git a/doc/Changelog b/doc/Changelog
index 85398c727253d15832e8e65fd9bb3d72da371132..d9922b351f63ab118a29a2a5cd6f0ce3590cb101 100644 (file)
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,3 +1,6 @@
+3 August 2016: Wouter
+       - use sendmsg instead of sendto for TFO.
+
 28 July 2016: Wouter
        - Fix #806: wrong comment removed.
 

diff --git a/util/netevent.c b/util/netevent.c
index 60ef918f04ec78440350f39288b5bd95bef361f9..8960b362c78d7607ab2e8276d2d509b38402aaf0 100644 (file)
--- a/util/netevent.c
+++ b/util/netevent.c
@@ -1360,30 +1360,26 @@ comm_point_tcp_handle_write(int fd, struct comm_point* c)
 #ifdef USE_MSG_FASTOPEN
        /* Only try this on first use of a connection that uses tfo, 
           otherwise fall through to normal write */
-       /* Also, TFO not available on WINDOWS at the moment */
+       /* Also, TFO support on WINDOWS not implemented at the moment */
        if(c->tcp_do_fastopen == 1) {
-               /* We need to have all the bytes to send in one buffer to try a single
-                  sendto() for the message to go in the syn packet, so we must
-                  create that buffer here, even though it means a malloc. 
-                  NOTE: When there is a general solution for composing a TCP message
-                   (inc length) in one buffer this code should use that mechanism.*/
-               struct sldns_buffer* sendto_buf = NULL;
-               uint16_t len = sldns_buffer_limit(c->buffer);
-               c->tcp_do_fastopen = 0;
-               sendto_buf = sldns_buffer_new(len + sizeof(uint16_t));
-               if (!sendto_buf)
-                       return 0;
-               sldns_buffer_write_u16_at(sendto_buf, 0, len);
-               sldns_buffer_write_at(sendto_buf, sizeof(uint16_t), 
-                                                 sldns_buffer_begin(c->buffer),
-                                                 sldns_buffer_limit(c->buffer));
-               r = sendto(fd, sldns_buffer_begin(sendto_buf), 
-                                       sldns_buffer_limit(sendto_buf),
-                                       MSG_FASTOPEN, (struct sockaddr*)&(c->repinfo.addr),
-                                       c->repinfo.addrlen);
-               sldns_buffer_free(sendto_buf);
-               /* this form of sendto() does both a connect() and send() so need to
+               /* this form of sendmsg() does both a connect() and send() so need to
                   look for various flavours of error*/
+               uint16_t len = htons(sldns_buffer_limit(c->buffer));
+               struct msghdr msg;
+               struct iovec iov[2];
+               c->tcp_do_fastopen = 0;
+               memset(&msg, 0, sizeof(msg));
+               iov[0].iov_base = (uint8_t*)&len + c->tcp_byte_count;
+               iov[0].iov_len = sizeof(uint16_t) - c->tcp_byte_count;
+               iov[1].iov_base = sldns_buffer_begin(c->buffer);
+               iov[1].iov_len = sldns_buffer_limit(c->buffer);
+               log_assert(iov[0].iov_len > 0);
+               log_assert(iov[1].iov_len > 0);
+               msg.msg_name = &c->repinfo.addr;
+               msg.msg_namelen = c->repinfo.addrlen;
+               msg.msg_iov = iov;
+               msg.msg_iovlen = 2;
+               r = sendmsg(fd, &msg, MSG_FASTOPEN);
                if (r == -1) {
 #if defined(EINPROGRESS) && defined(EWOULDBLOCK)
                        /* Handshake is underway, maybe because no TFO cookie available.
@@ -1397,7 +1393,7 @@ comm_point_tcp_handle_write(int fd, struct comm_point* c)
                        if(errno != 0 && verbosity < 2)
                                return 0; /* silence lots of chatter in the logs */
                        else if(errno != 0) 
-                               log_err_addr("tcp sendto", strerror(errno),
+                               log_err_addr("tcp sendmsg", strerror(errno),
                                        &c->repinfo.addr, c->repinfo.addrlen);
                        return 0;
                } else {