Index: openssh-7.4p1/HPN-README
===================================================================
--- /dev/null
+++ openssh-7.4p1/HPN-README
@@ -0,0 +1,130 @@
+Notes:
+
+MULTI-THREADED CIPHER:
+The AES cipher in CTR mode has been multithreaded (MTR-AES-CTR). This will allow ssh installations
+on hosts with multiple cores to use more than one processing core during encryption.
+Tests have show significant throughput performance increases when using MTR-AES-CTR up
+to and including a full gigabit per second on quad core systems. It should be possible to
+achieve full line rate on dual core systems but OS and data management overhead makes this
+more difficult to achieve. The cipher stream from MTR-AES-CTR is entirely compatible with single
+thread AES-CTR (ST-AES-CTR) implementations and should be 100% backward compatible. Optimal
+performance requires the MTR-AES-CTR mode be enabled on both ends of the connection.
+The MTR-AES-CTR replaces ST-AES-CTR and is used in exactly the same way with the same
+nomenclature.
+Use examples:
+		ssh -caes128-ctr you@host.com
+		scp -oCipher=aes256-ctr file you@host.com:~/file
+
+NONE CIPHER:
+To use the NONE option you must have the NoneEnabled switch set on the server and
+you *must* have *both* NoneEnabled and NoneSwitch set to yes on the client. The NONE
+feature works with ALL ssh subsystems (as far as we can tell) *AS LONG AS* a tty is not
+spawned. If a user uses the -T switch to prevent a tty being created the NONE cipher will
+be disabled.
+
+The performance increase will only be as good as the network and TCP stack tuning
+on the reciever side of the connection allows. As a rule of thumb a user will need
+at least 10Mb/s connection with a 100ms RTT to see a doubling of performance. The
+HPN-SSH home page describes this in greater detail.
+
+http://www.psc.edu/networking/projects/hpn-ssh
+
+BUFFER SIZES:
+
+If HPN is disabled the receive buffer size will be set to the
+OpenSSH default of 64K.
+
+If an HPN system connects to a nonHPN system the receive buffer will
+be set to the HPNBufferSize value. The default is 2MB but user adjustable.
+
+If an HPN to HPN connection is established a number of different things might
+happen based on the user options and conditions.
+
+Conditions: HPNBufferSize NOT Set, TCPRcvBufPoll enabled, TCPRcvBuf NOT Set
+HPN Buffer Size = up to 64MB
+This is the default state. The HPN buffer size will grow to a maximum of 64MB
+as the TCP receive buffer grows. The maximum HPN Buffer size of 64MB is
+geared towards 10GigE transcontinental connections.
+
+Conditions: HPNBufferSize NOT Set, TCPRcvBufPoll disabled, TCPRcvBuf NOT Set
+HPN Buffer Size = TCP receive buffer value.
+Users on non-autotuning systesm should disable TCPRcvBufPoll in the
+ssh_cofig and sshd_config
+
+Conditions: HPNBufferSize SET, TCPRcvBufPoll disabled, TCPRcvBuf NOT Set
+HPN Buffer Size = minmum of TCP receive buffer and HPNBufferSize.
+This would be the system defined TCP receive buffer (RWIN).
+
+Conditions: HPNBufferSize SET, TCPRcvBufPoll disabled, TCPRcvBuf SET
+HPN Buffer Size = minmum of TCPRcvBuf and HPNBufferSize.
+Generally there is no need to set both.
+
+Conditions: HPNBufferSize SET, TCPRcvBufPoll enabled, TCPRcvBuf NOT Set
+HPN Buffer Size = grows to HPNBufferSize
+The buffer will grow up to the maximum size specified here.
+
+Conditions: HPNBufferSize SET, TCPRcvBufPoll enabled, TCPRcvBuf SET
+HPN Buffer Size = minmum of TCPRcvBuf and HPNBufferSize.
+Generally there is no need to set both of these, especially on autotuning
+systems. However, if the users wishes to override the autotuning this would be
+one way to do it.
+
+Conditions: HPNBufferSize NOT Set, TCPRcvBufPoll enabled, TCPRcvBuf SET
+HPN Buffer Size = TCPRcvBuf.
+This will override autotuning and set the TCP recieve buffer to the user defined
+value.
+
+
+HPN Specific Configuration options
+
+TcpRcvBuf=[int]KB client
+      set the TCP socket receive buffer to n Kilobytes. It can be set up to the
+maximum socket size allowed by the system. This is useful in situations where
+the tcp receive window is set low but the maximum buffer size is set
+higher (as is typical). This works on a per TCP connection basis. You can also
+use this to artifically limit the transfer rate of the connection. In these
+cases the throughput will be no more than n/RTT. The minimum buffer size is 1KB.
+Default is the current system wide tcp receive buffer size.
+
+TcpRcvBufPoll=[yes/no] client/server
+      enable of disable the polling of the tcp receive buffer through the life
+of the connection. You would want to make sure that this option is enabled
+for systems making use of autotuning kernels (linux 2.4.24+, 2.6, MS Vista)
+default is yes.
+
+NoneEnabled=[yes/no] client/server
+      enable or disable the use of the None cipher. Care must always be used
+when enabling this as it will allow users to send data in the clear. However,
+it is important to note that authentication information remains encrypted
+even if this option is enabled. Set to no by default.
+
+NoneSwitch=[yes/no] client
+     Switch the encryption cipher being used to the None cipher after
+authentication takes place. NoneEnabled must be enabled on both the client
+and server side of the connection. When the connection switches to the NONE
+cipher a warning is sent to STDERR. The connection attempt will fail with an
+error if a client requests a NoneSwitch from the server that does not explicitly
+have NoneEnabled set to yes. Note: The NONE cipher cannot be used in
+interactive (shell) sessions and it will fail silently. Set to no by default.
+
+HPNDisabled=[yes/no] client/server
+     In some situations, such as transfers on a local area network, the impact
+of the HPN code produces a net decrease in performance. In these cases it is
+helpful to disable the HPN functionality. By default HPNDisabled is set to no.
+
+HPNBufferSize=[int]KB client/server
+     This is the default buffer size the HPN functionality uses when interacting
+with nonHPN SSH installations. Conceptually this is similar to the TcpRcvBuf
+option as applied to the internal SSH flow control. This value can range from
+1KB to 64MB (1-65536). Use of oversized or undersized buffers can cause performance
+problems depending on the length of the network path. The default size of this buffer
+is 2MB.
+
+
+Credits: This patch was conceived, designed, and led by Chris Rapier (rapier@psc.edu)
+         The majority of the actual coding for versions up to HPN12v1 was performed
+         by Michael Stevens (mstevens@andrew.cmu.edu). The MT-AES-CTR cipher was
+         implemented by Ben Bennet (ben@psc.edu) and improved by Mike Tasota
+         (tasota@gmail.com) an NSF REU grant recipient for 2013.
+         This work was financed, in part, by Cisco System, Inc., the National
+         Library of Medicine, and the National Science Foundation.
Index: openssh-7.4p1/channels.c
===================================================================
--- openssh-7.4p1.orig/channels.c
+++ openssh-7.4p1/channels.c
@@ -191,6 +191,10 @@ static const char *channel_rfwd_bind_hos
 static int connect_next(struct channel_connect *);
 static void channel_connect_ctx_free(struct channel_connect *);
 
+
+static int hpn_disabled = 0;
+static int hpn_buffer_size = 2 * 1024 * 1024;
+
 /* -- channel core */
 
 Channel *
@@ -356,6 +360,7 @@ channel_new(char *ctype, int type, int r
 	c->local_window_max = window;
 	c->local_consumed = 0;
 	c->local_maxpacket = maxpack;
+	c->dynamic_window = 0;
 	c->remote_id = -1;
 	c->remote_name = xstrdup(remote_name);
 	c->remote_window = 0;
@@ -904,11 +909,39 @@ channel_pre_open_13(Channel *c, fd_set *
 		FD_SET(c->sock, writeset);
 }
 
+static int
+channel_tcpwinsz(void)
+{
+	u_int32_t tcpwinsz = 0;
+	socklen_t optsz = sizeof(tcpwinsz);
+	int ret = -1;
+
+	/* if we aren't on a socket return 128KB */
+	if (!packet_connection_is_on_socket())
+		return 128 * 1024;
+
+	ret = getsockopt(packet_get_connection_in(),
+			 SOL_SOCKET, SO_RCVBUF, &tcpwinsz, &optsz);
+	/* return no more than SSHBUF_SIZE_MAX (currently 256MB) */
+	if ((ret == 0) && tcpwinsz > SSHBUF_SIZE_MAX)
+		tcpwinsz = SSHBUF_SIZE_MAX;
+
+	debug2("tcpwinsz: %d for connection: %d", tcpwinsz,
+	       packet_get_connection_in());
+	return tcpwinsz;
+}
+
 static void
 channel_pre_open(Channel *c, fd_set *readset, fd_set *writeset)
 {
 	u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
 
+	/* check buffer limits */
+	if ((!c->tcpwinsz) || (c->dynamic_window > 0))
+		c->tcpwinsz = channel_tcpwinsz();
+
+	limit = MIN(limit, 2 * c->tcpwinsz);
+
 	if (c->istate == CHAN_INPUT_OPEN &&
 	    limit > 0 &&
 	    buffer_len(&c->input) < limit &&
@@ -1926,14 +1959,21 @@ channel_check_window(Channel *c)
 	    c->local_maxpacket*3) ||
 	    c->local_window < c->local_window_max/2) &&
 	    c->local_consumed > 0) {
+		u_int addition = 0;
+		/* adjust max window size if we are in a dynamic environment */
+		if (c->dynamic_window && (c->tcpwinsz > c->local_window_max)) {
+			/* grow the window somewhat aggressively to maintain pressure */
+			addition = 1.5 * (c->tcpwinsz - c->local_window_max);
+			c->local_window_max += addition;
+		}
 		packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
 		packet_put_int(c->remote_id);
-		packet_put_int(c->local_consumed);
+		packet_put_int(c->local_consumed + addition);
 		packet_send();
 		debug2("channel %d: window %d sent adjust %d",
 		    c->self, c->local_window,
 		    c->local_consumed);
-		c->local_window += c->local_consumed;
+		c->local_window += c->local_consumed + addition;
 		c->local_consumed = 0;
 	}
 	return 1;
@@ -3179,6 +3219,15 @@ channel_fwd_bind_addr(const char *listen
 	return addr;
 }
 
+
+void
+channel_set_hpn(int external_hpn_disabled, int external_hpn_buffer_size)
+{
+	hpn_disabled = external_hpn_disabled;
+	hpn_buffer_size = external_hpn_buffer_size;
+	debug("HPN Disabled: %d, HPN Buffer Size: %d", hpn_disabled, hpn_buffer_size);
+}
+
 static int
 channel_setup_fwd_listener_tcpip(int type, struct Forward *fwd,
     int *allocated_listen_port, struct ForwardOptions *fwd_opts)
@@ -3307,9 +3356,15 @@ channel_setup_fwd_listener_tcpip(int typ
 		}
 
 		/* Allocate a channel number for the socket. */
-		c = channel_new("port listener", type, sock, sock, -1,
-		    CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
-		    0, "port listener", 1);
+		/* explicitly test for hpn disabled option. if true use smaller window size */
+		if (hpn_disabled)
+			c = channel_new("port listener", type, sock, sock, -1,
+			    CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
+			    0, "port listener", 1);
+		else
+			c = channel_new("port listener", type, sock, sock, -1,
+			    hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT,
+			    0, "port listener", 1);
 		c->path = xstrdup(host);
 		c->host_port = fwd->connect_port;
 		c->listening_addr = addr == NULL ? NULL : xstrdup(addr);
@@ -4313,10 +4368,17 @@ x11_create_display_inet(int x11_display_
 	*chanids = xcalloc(num_socks + 1, sizeof(**chanids));
 	for (n = 0; n < num_socks; n++) {
 		sock = socks[n];
+		/* Is this really necassary? */
+		if (hpn_disabled)
 		nc = channel_new("x11 listener",
 		    SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
 		    CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
 		    0, "X11 inet listener", 1);
+		else
+			nc = channel_new("x11 listener",
+			    SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
+			    hpn_buffer_size, CHAN_X11_PACKET_DEFAULT,
+			    0, "X11 inet listener", 1);
 		nc->single_connection = single_connection;
 		(*chanids)[n] = nc->self;
 	}
Index: openssh-7.4p1/channels.h
===================================================================
--- openssh-7.4p1.orig/channels.h
+++ openssh-7.4p1/channels.h
@@ -135,8 +135,10 @@ struct Channel {
 	u_int	local_window_max;
 	u_int	local_consumed;
 	u_int	local_maxpacket;
+	int	dynamic_window;
 	int     extended_usage;
 	int	single_connection;
+	u_int	tcpwinsz;
 
 	char   *ctype;		/* type */
 
@@ -319,4 +321,7 @@ void	 chan_rcvd_ieof(Channel *);
 void	 chan_write_failed(Channel *);
 void	 chan_obuf_empty(Channel *);
 
+/* hpn handler */
+void     channel_set_hpn(int, int);
+
 #endif
Index: openssh-7.4p1/clientloop.c
===================================================================
--- openssh-7.4p1.orig/clientloop.c
+++ openssh-7.4p1/clientloop.c
@@ -2005,9 +2005,15 @@ client_request_x11(const char *request_t
 	sock = x11_connect_display();
 	if (sock < 0)
 		return NULL;
+	/* again is this really necessary for X11? */
+	if (options.hpn_disabled)
 	c = channel_new("x11",
 	    SSH_CHANNEL_X11_OPEN, sock, sock, -1,
 	    CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
+	else
+		c = channel_new("x11",
+		    SSH_CHANNEL_X11_OPEN, sock, sock, -1,
+		    options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
 	c->force_drain = 1;
 	return c;
 }
@@ -2030,9 +2036,15 @@ client_request_agent(const char *request
 			    __func__, ssh_err(r));
 		return NULL;
 	}
+	if (options.hpn_disabled)
 	c = channel_new("authentication agent connection",
 	    SSH_CHANNEL_OPEN, sock, sock, -1,
-	    CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
+		    CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
+		    "authentication agent connection", 1);
+	else
+	c = channel_new("authentication agent connection",
+	    SSH_CHANNEL_OPEN, sock, sock, -1,
+	    options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT, 0,
 	    "authentication agent connection", 1);
 	c->force_drain = 1;
 	return c;
@@ -2060,10 +2072,18 @@ client_request_tun_fwd(int tun_mode, int
 		return -1;
 	}
 
+	if(options.hpn_disabled)
+	c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
+				CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
+				0, "tun", 1);
+	else
 	c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
-	    CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
+				options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT,
+				0, "tun", 1);
 	c->datagram = 1;
 
+
+
 #if defined(SSH_TUN_FILTER)
 	if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
 		channel_register_filter(c->self, sys_tun_infilter,
Index: openssh-7.4p1/compat.c
===================================================================
--- openssh-7.4p1.orig/compat.c
+++ openssh-7.4p1/compat.c
@@ -213,6 +213,13 @@ compat_datafellows(const char *version)
 			debug("match: %s pat %s compat 0x%08x",
 			    version, check[i].pat, check[i].bugs);
 			datafellows = check[i].bugs;	/* XXX for now */
+			/* Check to see if the remote side is OpenSSH and not HPN */
+			if (strstr(version, "OpenSSH") != NULL) {
+				if (strstr(version, "hpn") == NULL) {
+					datafellows |= SSH_BUG_LARGEWINDOW;
+					debug("Remote is NON-HPN aware");
+				}
+			}
 			return check[i].bugs;
 		}
 	}
Index: openssh-7.4p1/compat.h
===================================================================
--- openssh-7.4p1.orig/compat.h
+++ openssh-7.4p1/compat.h
@@ -62,6 +62,7 @@
 #define SSH_BUG_CURVE25519PAD	0x10000000
 #define SSH_BUG_HOSTKEYS	0x20000000
 #define SSH_BUG_DHGEX_LARGE	0x40000000
+#define SSH_BUG_LARGEWINDOW	0x80000000
 
 void     enable_compat13(void);
 void     enable_compat20(void);
Index: openssh-7.4p1/readconf.c
===================================================================
--- openssh-7.4p1.orig/readconf.c
+++ openssh-7.4p1/readconf.c
@@ -66,6 +66,7 @@
 #include "uidswap.h"
 #include "myproposal.h"
 #include "digest.h"
+#include "sshbuf.h"
 
 /* Format of the configuration file:
 
@@ -166,6 +167,7 @@ typedef enum {
 	oSendEnv, oControlPath, oControlMaster, oControlPersist,
 	oHashKnownHosts,
 	oTunnel, oTunnelDevice, oLocalCommand, oPermitLocalCommand,
+	oTcpRcvBufPoll, oTcpRcvBuf, oHPNDisabled, oHPNBufferSize,
 	oVisualHostKey,
 	oKexAlgorithms, oIPQoS, oRequestTTY, oIgnoreUnknown, oProxyUseFdpass,
 	oCanonicalDomains, oCanonicalizeHostname, oCanonicalizeMaxDots,
@@ -312,6 +314,11 @@ static struct {
 	{ "protocolkeepalives", oProtocolKeepAlives },
 	{ "setuptimeout", oSetupTimeOut },
 
+	{ "tcprcvbufpoll", oTcpRcvBufPoll },
+	{ "tcprcvbuf", oTcpRcvBuf },
+	{ "hpndisabled", oHPNDisabled },
+	{ "hpnbuffersize", oHPNBufferSize },
+
 	{ NULL, oBadOption }
 };
 
@@ -1008,6 +1015,18 @@ parse_time:
 		intptr = &options->check_host_ip;
 		goto parse_flag;
 
+	case oHPNDisabled:
+		intptr = &options->hpn_disabled;
+		goto parse_flag;
+
+	case oHPNBufferSize:
+		intptr = &options->hpn_buffer_size;
+		goto parse_int;
+
+	case oTcpRcvBufPoll:
+		intptr = &options->tcp_rcv_buf_poll;
+		goto parse_flag;
+
 	case oVerifyHostKeyDNS:
 		intptr = &options->verify_host_key_dns;
 		multistate_ptr = multistate_yesnoask;
@@ -1200,6 +1219,10 @@ parse_int:
 		intptr = &options->connection_attempts;
 		goto parse_int;
 
+	case oTcpRcvBuf:
+		intptr = &options->tcp_rcv_buf;
+		goto parse_int;
+
 	case oCipher:
 		intptr = &options->cipher;
 		arg = strdelim(&s);
@@ -1886,6 +1909,10 @@ initialize_options(Options * options)
 	options->ip_qos_interactive = -1;
 	options->ip_qos_bulk = -1;
 	options->request_tty = -1;
+	options->hpn_disabled = -1;
+	options->hpn_buffer_size = -1;
+	options->tcp_rcv_buf_poll = -1;
+	options->tcp_rcv_buf = -1;
 	options->proxy_use_fdpass = -1;
 	options->ignored_unknown = NULL;
 	options->num_canonical_domains = 0;
@@ -2060,6 +2087,26 @@ fill_default_options(Options * options)
 	}
 	if (options->server_alive_count_max == -1)
 		options->server_alive_count_max = 3;
+	if (options->hpn_disabled == -1)
+		options->hpn_disabled = 0;
+	if (options->hpn_buffer_size > -1) {
+		/* if a user tries to set the size to 0 set it to 1KB */
+		if (options->hpn_buffer_size == 0)
+			options->hpn_buffer_size = 1;
+		/* limit the buffer to SSHBUF_SIZE_MAX (currently 256MB) */
+		if (options->hpn_buffer_size > (SSHBUF_SIZE_MAX / 1024)) {
+			options->hpn_buffer_size = SSHBUF_SIZE_MAX;
+			debug("User requested buffer larger than 256MB. Request reverted to 256MB");
+		} else
+			options->hpn_buffer_size *= 1024;
+		debug("hpn_buffer_size set to %d", options->hpn_buffer_size);
+	}
+	if (options->tcp_rcv_buf == 0)
+		options->tcp_rcv_buf = 1;
+	if (options->tcp_rcv_buf > -1)
+		options->tcp_rcv_buf *=1024;
+	if (options->tcp_rcv_buf_poll == -1)
+		options->tcp_rcv_buf_poll = 1;
 	if (options->control_master == -1)
 		options->control_master = 0;
 	if (options->control_persist == -1) {
Index: openssh-7.4p1/readconf.h
===================================================================
--- openssh-7.4p1.orig/readconf.h
+++ openssh-7.4p1/readconf.h
@@ -62,6 +62,10 @@ typedef struct {
 	int     compression_level;	/* Compression level 1 (fast) to 9
 					 * (best). */
 	int     tcp_keep_alive;	/* Set SO_KEEPALIVE. */
+	int     tcp_rcv_buf; /* user switch to set tcp recv buffer */
+	int     tcp_rcv_buf_poll; /* Option to poll recv buf every window transfer */
+	int     hpn_disabled;    /* Switch to disable HPN buffer management */
+	int     hpn_buffer_size; /* User definable size for HPN buffer window */
 	int	ip_qos_interactive;	/* IP ToS/DSCP/class for interactive */
 	int	ip_qos_bulk;		/* IP ToS/DSCP/class for bulk traffic */
 	LogLevel log_level;	/* Level for logging. */
Index: openssh-7.4p1/scp.c
===================================================================
--- openssh-7.4p1.orig/scp.c
+++ openssh-7.4p1/scp.c
@@ -771,7 +771,7 @@ source(int argc, char **argv)
 	off_t i, statbytes;
 	size_t amt, nr;
 	int fd = -1, haderr, indx;
-	char *last, *name, buf[2048], encname[PATH_MAX];
+	char *last, *name, buf[16384], encname[PATH_MAX];
 	int len;
 
 	for (indx = 0; indx < argc; ++indx) {
Index: openssh-7.4p1/servconf.c
===================================================================
--- openssh-7.4p1.orig/servconf.c
+++ openssh-7.4p1/servconf.c
@@ -57,6 +57,7 @@
 #include "auth.h"
 #include "myproposal.h"
 #include "digest.h"
+#include "sshbuf.h"
 
 static void add_listen_addr(ServerOptions *, char *, int);
 static void add_one_listen_addr(ServerOptions *, char *, int);
@@ -161,6 +162,9 @@ initialize_server_options(ServerOptions
 	options->authorized_principals_file = NULL;
 	options->authorized_principals_command = NULL;
 	options->authorized_principals_command_user = NULL;
+	options->tcp_rcv_buf_poll = -1;
+	options->hpn_disabled = -1;
+	options->hpn_buffer_size = -1;
 	options->ip_qos_interactive = -1;
 	options->ip_qos_bulk = -1;
 	options->version_addendum = NULL;
@@ -194,6 +198,10 @@ void
 fill_default_server_options(ServerOptions *options)
 {
 	int i;
+	/* needed for hpn socket tests */
+	int sock;
+	int socksize;
+	int socksizelen = sizeof(int);
 
 	/* Portable-specific options */
 	if (options->use_pam == -1)
@@ -324,6 +332,41 @@ fill_default_server_options(ServerOption
 	}
 	if (options->permit_tun == -1)
 		options->permit_tun = SSH_TUNMODE_NO;
+	if (options->hpn_disabled == -1)
+		options->hpn_disabled = 0;
+
+	if (options->hpn_buffer_size == -1) {
+		/* option not explicitly set. Now we have to figure out */
+		/* what value to use */
+		if (options->hpn_disabled == 1) {
+			options->hpn_buffer_size = CHAN_SES_WINDOW_DEFAULT;
+		} else {
+			/* get the current RCV size and set it to that */
+			/*create a socket but don't connect it */
+			/* we use that the get the rcv socket size */
+			sock = socket(AF_INET, SOCK_STREAM, 0);
+			getsockopt(sock, SOL_SOCKET, SO_RCVBUF,
+				   &socksize, &socksizelen);
+			close(sock);
+			options->hpn_buffer_size = socksize;
+			debug("HPN Buffer Size: %d", options->hpn_buffer_size);
+		}
+	} else {
+		/* we have to do this in case the user sets both values in a contradictory */
+		/* manner. hpn_disabled overrrides hpn_buffer_size*/
+		if (options->hpn_disabled <= 0) {
+			if (options->hpn_buffer_size == 0)
+				options->hpn_buffer_size = 1;
+			/* limit the maximum buffer to SSHBUF_SIZE_MAX (currently 256MB) */
+			if (options->hpn_buffer_size > (SSHBUF_SIZE_MAX / 1024)) {
+				options->hpn_buffer_size = SSHBUF_SIZE_MAX;
+			} else {
+				options->hpn_buffer_size *= 1024;
+			}
+		} else
+			options->hpn_buffer_size = CHAN_TCP_WINDOW_DEFAULT;
+	}
+
 	if (options->ip_qos_interactive == -1)
 		options->ip_qos_interactive = IPTOS_LOWDELAY;
 	if (options->ip_qos_bulk == -1)
@@ -402,6 +445,7 @@ typedef enum {
 	sPasswordAuthentication, sKbdInteractiveAuthentication,
 	sListenAddress, sAddressFamily,
 	sPrintMotd, sPrintLastLog, sIgnoreRhosts,
+	sTcpRcvBufPoll, sHPNDisabled, sHPNBufferSize,
 	sX11Forwarding, sX11DisplayOffset, sX11UseLocalhost,
 	sPermitTTY, sStrictModes, sEmptyPasswd, sTCPKeepAlive,
 	sPermitUserEnvironment, sAllowTcpForwarding, sCompression,
@@ -566,6 +610,9 @@ static struct {
 	{ "revokedkeys", sRevokedKeys, SSHCFG_ALL },
 	{ "trustedusercakeys", sTrustedUserCAKeys, SSHCFG_ALL },
 	{ "authorizedprincipalsfile", sAuthorizedPrincipalsFile, SSHCFG_ALL },
+	{ "hpndisabled", sHPNDisabled, SSHCFG_ALL },
+	{ "hpnbuffersize", sHPNBufferSize, SSHCFG_ALL },
+	{ "tcprcvbufpoll", sTcpRcvBufPoll, SSHCFG_ALL },
 	{ "kexalgorithms", sKexAlgorithms, SSHCFG_GLOBAL },
 	{ "ipqos", sIPQoS, SSHCFG_ALL },
 	{ "authorizedkeyscommand", sAuthorizedKeysCommand, SSHCFG_ALL },
@@ -606,6 +653,7 @@ parse_token(const char *cp, const char *
 
 	for (i = 0; keywords[i].name; i++)
 		if (strcasecmp(cp, keywords[i].name) == 0) {
+			debug("Config token is %s", keywords[i].name);
 			*flags = keywords[i].flags;
 			return keywords[i].opcode;
 		}
@@ -1168,6 +1216,19 @@ process_server_config_line(ServerOptions
 			*intptr = value;
 		break;
 
+
+	case sTcpRcvBufPoll:
+		intptr = &options->tcp_rcv_buf_poll;
+		goto parse_flag;
+
+	case sHPNDisabled:
+		intptr = &options->hpn_disabled;
+		goto parse_flag;
+
+	case sHPNBufferSize:
+		intptr = &options->hpn_buffer_size;
+		goto parse_int;
+
 	case sIgnoreUserKnownHosts:
 		intptr = &options->ignore_user_known_hosts;
 		goto parse_flag;
Index: openssh-7.4p1/servconf.h
===================================================================
--- openssh-7.4p1.orig/servconf.h
+++ openssh-7.4p1/servconf.h
@@ -168,6 +168,9 @@ typedef struct {
 	char   *adm_forced_command;
 
 	int	use_pam;		/* Enable auth via PAM */
+        int     tcp_rcv_buf_poll;       /* poll tcp rcv window in autotuning kernels*/
+	int	hpn_disabled;		/* disable hpn functionality. false by default */
+	int	hpn_buffer_size;	/* set the hpn buffer size - default 3MB */
 
 	int	permit_tun;
 
Index: openssh-7.4p1/serverloop.c
===================================================================
--- openssh-7.4p1.orig/serverloop.c
+++ openssh-7.4p1/serverloop.c
@@ -530,8 +530,12 @@ server_request_tun(void)
 	sock = tun_open(tun, mode);
 	if (sock < 0)
 		goto done;
+	if (options.hpn_disabled)
 	c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1,
 	    CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
+	else
+		c = channel_new("tun", SSH_CHANNEL_OPEN, sock, sock, -1,
+		    options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
 	c->datagram = 1;
 #if defined(SSH_TUN_FILTER)
 	if (mode == SSH_TUNMODE_POINTOPOINT)
@@ -567,6 +571,8 @@ server_request_session(void)
 	c = channel_new("session", SSH_CHANNEL_LARVAL,
 	    -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT,
 	    0, "server-session", 1);
+	if ((options.tcp_rcv_buf_poll) && (!options.hpn_disabled))
+		c->dynamic_window = 1;
 	if (session_open(the_authctxt, c->self) != 1) {
 		debug("session open failed, free channel %d", c->self);
 		channel_free(c);
Index: openssh-7.4p1/session.c
===================================================================
--- openssh-7.4p1.orig/session.c
+++ openssh-7.4p1/session.c
@@ -220,6 +220,7 @@ auth_input_request_forwarding(struct pas
 		goto authsock_err;
 
 	/* Allocate a channel for the authentication agent socket. */
+	/* this shouldn't matter if its hpn or not - cjr */
 	nc = channel_new("auth socket",
 	    SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
 	    CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
@@ -2121,10 +2122,16 @@ session_set_fds(Session *s, int fdin, in
 	 */
 	if (s->chanid == -1)
 		fatal("no channel for session %d", s->self);
+	if (options.hpn_disabled)
 	channel_set_fds(s->chanid,
 	    fdout, fdin, fderr,
 	    ignore_fderr ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
 	    1, is_tty, CHAN_SES_WINDOW_DEFAULT);
+	else
+		channel_set_fds(s->chanid,
+		    fdout, fdin, fderr,
+		    ignore_fderr ? CHAN_EXTENDED_IGNORE : CHAN_EXTENDED_READ,
+		    1, is_tty, options.hpn_buffer_size);
 }
 
 /*
Index: openssh-7.4p1/sftp.1
===================================================================
--- openssh-7.4p1.orig/sftp.1
+++ openssh-7.4p1/sftp.1
@@ -266,7 +266,8 @@ diagnostic messages from
 Specify how many requests may be outstanding at any one time.
 Increasing this may slightly improve file transfer speed
 but will increase memory usage.
-The default is 64 outstanding requests.
+The default is 256 outstanding requests providing for 8MB
+of outstanding data with a 32KB buffer.
 .It Fl r
 Recursively copy entire directories when uploading and downloading.
 Note that
Index: openssh-7.4p1/sftp.c
===================================================================
--- openssh-7.4p1.orig/sftp.c
+++ openssh-7.4p1/sftp.c
@@ -72,7 +72,7 @@ typedef void EditLine;
 #include "sftp-client.h"
 
 #define DEFAULT_COPY_BUFLEN	32768	/* Size of buffer for up/download */
-#define DEFAULT_NUM_REQUESTS	64	/* # concurrent outstanding requests */
+#define DEFAULT_NUM_REQUESTS	256	/* # concurrent outstanding requests */
 
 /* File to read commands from */
 FILE* infile;
Index: openssh-7.4p1/ssh.c
===================================================================
--- openssh-7.4p1.orig/ssh.c
+++ openssh-7.4p1/ssh.c
@@ -1907,6 +1907,78 @@ ssh_session2_setup(int id, int success,
 	    NULL, fileno(stdin), &command, environ);
 }
 
+static void
+hpn_options_init(void)
+{
+	/*
+	 * We need to check to see if what they want to do about buffer
+	 * sizes here. In a hpn to nonhpn connection we want to limit
+	 * the window size to something reasonable in case the far side
+	 * has the large window bug. In hpn to hpn connection we want to
+	 * use the max window size but allow the user to override it
+	 * lastly if they disabled hpn then use the ssh std window size.
+	 *
+	 * So why don't we just do a getsockopt() here and set the
+	 * ssh window to that? In the case of a autotuning receive
+	 * window the window would get stuck at the initial buffer
+	 * size generally less than 96k. Therefore we need to set the
+	 * maximum ssh window size to the maximum hpn buffer size
+	 * unless the user has specifically set the tcprcvbufpoll
+	 * to no. In which case we *can* just set the window to the
+	 * minimum of the hpn buffer size and tcp receive buffer size.
+	 */
+
+	if (tty_flag)
+		options.hpn_buffer_size = CHAN_SES_WINDOW_DEFAULT;
+	else
+		options.hpn_buffer_size = 2 * 1024 * 1024;
+
+	if (datafellows & SSH_BUG_LARGEWINDOW) {
+		debug("HPN to Non-HPN Connection");
+	} else {
+		int sock, socksize;
+		socklen_t socksizelen;
+		if (options.tcp_rcv_buf_poll <= 0) {
+			sock = socket(AF_INET, SOCK_STREAM, 0);
+			socksizelen = sizeof(socksize);
+			getsockopt(sock, SOL_SOCKET, SO_RCVBUF,
+				   &socksize, &socksizelen);
+			close(sock);
+			debug("socksize %d", socksize);
+			options.hpn_buffer_size = socksize;
+			debug("HPNBufferSize set to TCP RWIN: %d", options.hpn_buffer_size);
+		} else {
+			if (options.tcp_rcv_buf > 0) {
+				/*
+				 * Create a socket but don't connect it:
+				 * we use that the get the rcv socket size
+				 */
+				sock = socket(AF_INET, SOCK_STREAM, 0);
+				/*
+				 * If they are using the tcp_rcv_buf option,
+				 * attempt to set the buffer size to that.
+				 */
+				if (options.tcp_rcv_buf) {
+					socksizelen = sizeof(options.tcp_rcv_buf);
+					setsockopt(sock, SOL_SOCKET, SO_RCVBUF,
+						   &options.tcp_rcv_buf, socksizelen);
+				}
+				socksizelen = sizeof(socksize);
+				getsockopt(sock, SOL_SOCKET, SO_RCVBUF,
+					   &socksize, &socksizelen);
+				close(sock);
+				debug("socksize %d", socksize);
+				options.hpn_buffer_size = socksize;
+				debug("HPNBufferSize set to user TCPRcvBuf: %d", options.hpn_buffer_size);
+			}
+		}
+	}
+
+	debug("Final hpn_buffer_size = %d", options.hpn_buffer_size);
+
+	channel_set_hpn(options.hpn_disabled, options.hpn_buffer_size);
+}
+
 /* open new channel for a session */
 static int
 ssh_session2_open(void)
@@ -1933,9 +2005,11 @@ ssh_session2_open(void)
 	if (!isatty(err))
 		set_nonblock(err);
 
-	window = CHAN_SES_WINDOW_DEFAULT;
+	window = options.hpn_buffer_size;
+
 	packetmax = CHAN_SES_PACKET_DEFAULT;
 	if (tty_flag) {
+		window = CHAN_SES_WINDOW_DEFAULT;
 		window >>= 1;
 		packetmax >>= 1;
 	}
@@ -1944,6 +2018,10 @@ ssh_session2_open(void)
 	    window, packetmax, CHAN_EXTENDED_WRITE,
 	    "client-session", /*nonblock*/0);
 
+	if ((options.tcp_rcv_buf_poll > 0) && (!options.hpn_disabled)) {
+		c->dynamic_window = 1;
+		debug("Enabled Dynamic Window Scaling");
+	}
 	debug3("ssh_session2_open: channel_new: %d", c->self);
 
 	channel_send_open(c->self);
@@ -1959,6 +2037,13 @@ ssh_session2(void)
 {
 	int id = -1;
 
+	/*
+	 * We need to initialize this early because the forwarding logic below
+	 * might open channels that use the hpn buffer sizes.  We can't send a
+	 * window of -1 (the default) to the server as it breaks things.
+	 */
+	hpn_options_init();
+
 	/* XXX should be pre-session */
 	if (!options.control_persist)
 		ssh_init_stdio_forwarding();
Index: openssh-7.4p1/sshbuf.h
===================================================================
--- openssh-7.4p1.orig/sshbuf.h
+++ openssh-7.4p1/sshbuf.h
@@ -28,7 +28,7 @@
 # endif /* OPENSSL_HAS_ECC */
 #endif /* WITH_OPENSSL */
 
-#define SSHBUF_SIZE_MAX		0x8000000	/* Hard maximum size */
+#define SSHBUF_SIZE_MAX		0xF000000	/* Hard maximum size 256MB */
 #define SSHBUF_REFS_MAX		0x100000	/* Max child buffers */
 #define SSHBUF_MAX_BIGNUM	(16384 / 8)	/* Max bignum *bytes* */
 #define SSHBUF_MAX_ECPOINT	((528 * 2 / 8) + 1) /* Max EC point *bytes* */
Index: openssh-7.4p1/sshconnect.c
===================================================================
--- openssh-7.4p1.orig/sshconnect.c
+++ openssh-7.4p1/sshconnect.c
@@ -267,6 +267,31 @@ ssh_kill_proxy_command(void)
 }
 
 /*
+ * Set TCP receive buffer if requested.
+ * Note: tuning needs to happen after the socket is
+ * created but before the connection happens
+ * so winscale is negotiated properly -cjr
+ */
+static void
+ssh_set_socket_recvbuf(int sock)
+{
+	void *buf = (void *)&options.tcp_rcv_buf;
+	int sz = sizeof(options.tcp_rcv_buf);
+	int socksize;
+	int socksizelen = sizeof(int);
+
+	debug("setsockopt Attempting to set SO_RCVBUF to %d", options.tcp_rcv_buf);
+	if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF, buf, sz) >= 0) {
+	  getsockopt(sock, SOL_SOCKET, SO_RCVBUF, &socksize, &socksizelen);
+	  debug("setsockopt SO_RCVBUF: %.100s %d", strerror(errno), socksize);
+	}
+	else
+		error("Couldn't set socket receive buffer to %d: %.100s",
+		    options.tcp_rcv_buf, strerror(errno));
+}
+
+
+/*
  * Creates a (possibly privileged) socket for use as the ssh connection.
  */
 static int
@@ -282,6 +307,9 @@ ssh_create_socket(int privileged, struct
 	}
 	fcntl(sock, F_SETFD, FD_CLOEXEC);
 
+	if (options.tcp_rcv_buf > 0)
+		ssh_set_socket_recvbuf(sock);
+
 	/* Bind the socket to an alternative local IP address */
 	if (options.bind_address == NULL && !privileged)
 		return sock;
Index: openssh-7.4p1/sshd.c
===================================================================
--- openssh-7.4p1.orig/sshd.c
+++ openssh-7.4p1/sshd.c
@@ -1036,6 +1036,8 @@ server_listen(void)
 	int ret, listen_sock, on = 1;
 	struct addrinfo *ai;
 	char ntop[NI_MAXHOST], strport[NI_MAXSERV];
+	int socksize;
+	int socksizelen = sizeof(int);
 
 	for (ai = options.listen_addrs; ai; ai = ai->ai_next) {
 		if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
@@ -1076,6 +1078,11 @@ server_listen(void)
 
 		debug("Bind to port %s on %s.", strport, ntop);
 
+		getsockopt(listen_sock, SOL_SOCKET, SO_RCVBUF,
+				   &socksize, &socksizelen);
+		debug("Server TCP RWIN socket size: %d", socksize);
+		debug("HPN Buffer Size: %d", options.hpn_buffer_size);
+
 		/* Bind the socket to the desired port. */
 		if (bind(listen_sock, ai->ai_addr, ai->ai_addrlen) < 0) {
 			error("Bind to port %s on %s failed: %.200s.",
@@ -1995,6 +2002,9 @@ main(int ac, char **av)
 		cleanup_exit(255);
 	}
 
+	/* set the HPN options for the child */
+	channel_set_hpn(options.hpn_disabled, options.hpn_buffer_size);
+
 	/*
 	 * The rest of the code depends on the fact that
 	 * ssh_remote_ipaddr() caches the remote ip, even if
Index: openssh-7.4p1/sshd_config
===================================================================
--- openssh-7.4p1.orig/sshd_config
+++ openssh-7.4p1/sshd_config
@@ -115,6 +115,16 @@ AcceptEnv LANG LC_*
 # override default of no subsystems
 Subsystem	sftp	/usr/lib/openssh/sftp-server
 
+# the following are HPN related configuration options
+# tcp receive buffer polling. disable in non autotuning kernels
+#TcpRcvBufPoll yes
+
+# disable hpn performance boosts
+#HPNDisabled no
+
+# buffer size for hpn to non-hpn connections
+#HPNBufferSize 2048
+
 # Example of overriding settings on a per-user basis
 #Match User anoncvs
 #	X11Forwarding no
Index: openssh-7.4p1/version.h
===================================================================
--- openssh-7.4p1.orig/version.h
+++ openssh-7.4p1/version.h
@@ -3,7 +3,8 @@
 #define SSH_VERSION	"OpenSSH_7.4"
 
 #define SSH_PORTABLE	"p1"
-#define SSH_RELEASE_MINIMUM	SSH_VERSION SSH_PORTABLE
+#define SSH_HPN         "-hpn14v12"
+#define SSH_RELEASE_MINIMUM	SSH_VERSION SSH_PORTABLE SSH_HPN
 #ifdef SSH_EXTRAVERSION
 #define SSH_RELEASE	SSH_RELEASE_MINIMUM " " SSH_EXTRAVERSION
 #else
