- djm@cvs.openbsd.org 2006/04/16 00:54:10

     [sftp-client.c]
     avoid making a tiny 4-byte write to send the packet length of sftp
     commands, which would result in a separate tiny packet on the wire by
     using atomiciov(writev, ...) to write the length and the command in one
     pass; ok deraadt@

2 files changed, 15 insertions, 6 deletions

diff --git a/ChangeLog b/ChangeLog
index 812312bd9..0a597a4fe 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -31,6 +31,12 @@
      introduce atomiciov() function that wraps readv/writev to retry
      interrupted transfers like atomicio() does for read/write;
      feedback deraadt@ dtucker@ stevesk@ ok deraadt@
+   - djm@cvs.openbsd.org 2006/04/16 00:54:10
+     [sftp-client.c]
+     avoid making a tiny 4-byte write to send the packet length of sftp
+     commands, which would result in a separate tiny packet on the wire by
+     using atomiciov(writev, ...) to write the length and the command in one
+     pass; ok deraadt@
 
 20060421
  - (djm) [Makefile.in configure.ac session.c sshpty.c]
@@ -4542,4 +4548,4 @@
    - (djm) Trim deprecated options from INSTALL. Mention UsePAM
    - (djm) Fix quote handling in sftp; Patch from admorten AT umich.edu
 
-$Id: ChangeLog,v 1.4308 2006/04/23 02:06:20 djm Exp $
+$Id: ChangeLog,v 1.4309 2006/04/23 02:06:35 djm Exp $
diff --git a/sftp-client.c b/sftp-client.c
index c71c66f33..8778439b9 100644
--- a/sftp-client.c
+++ b/sftp-client.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sftp-client.c,v 1.64 2006/03/30 09:58:16 djm Exp $ */
+/* $OpenBSD: sftp-client.c,v 1.65 2006/04/16 00:54:10 djm Exp $ */
 /*
  * Copyright (c) 2001-2004 Damien Miller <djm@openbsd.org>
  *
@@ -61,16 +61,19 @@ static void
 send_msg(int fd, Buffer *m)
 {
 	u_char mlen[4];
+	struct iovec iov[2];
 
 	if (buffer_len(m) > SFTP_MAX_MSG_LENGTH)
 		fatal("Outbound message too long %u", buffer_len(m));
 
 	/* Send length first */
 	put_u32(mlen, buffer_len(m));
-	if (atomicio(vwrite, fd, mlen, sizeof(mlen)) != sizeof(mlen))
-		fatal("Couldn't send packet: %s", strerror(errno));
-
-	if (atomicio(vwrite, fd, buffer_ptr(m), buffer_len(m)) != buffer_len(m))
+	iov[0].iov_base = mlen;
+	iov[0].iov_len = sizeof(mlen);
+	iov[1].iov_base = buffer_ptr(m);
+	iov[1].iov_len = buffer_len(m);
+	
+	if (atomiciov(writev, fd, iov, 2) != buffer_len(m) + sizeof(mlen))
 		fatal("Couldn't send packet: %s", strerror(errno));
 
 	buffer_clear(m);