um: add ucast ethernet transport

4ff4d8d3 · Nolan Leake <[email protected]> · 2011-05-24 17:13:02 -07:00

The ucast transport is similar to the mcast transport (and, in fact,
shares most of its code), only it uses UDP unicast to move packets.

Obviously this is only useful for point-to-point connections between
virtual ethernet devices.

Signed-off-by: Nolan Leake <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>
Cc: David Miller <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Commit: 4ff4d8d342fe25c4d1106fb0ffdd310a43d0ace0
Parents: d634f194

Changes

6 files changed · +227 −125

File	Status	Add	Del	Content
Documentation/virtual/uml/UserModeLinux-HOWTO.txt	modified	+10	−0	View file
arch/um/drivers/Makefile	modified	+2	−2	View file
arch/um/drivers/mcast.h	deleted	+0	−24	View before deletion
arch/um/drivers/umcast.h	added	+27	−0	View file
arch/um/drivers/mcast_kern.c → arch/um/drivers/umcast_kern.c	renamed	+102	−34	View file
arch/um/drivers/mcast_user.c → arch/um/drivers/umcast_user.c	renamed	+86	−65	View file

Documentation/virtual/uml/UserModeLinux-HOWTO.txt

View file

diff --git a/Documentation/virtual/uml/UserModeLinux-HOWTO.txt b/Documentation/virtual/uml/UserModeLinux-HOWTO.txt
index 9b7e190..5d0fc8b 100644
--- a/Documentation/virtual/uml/UserModeLinux-HOWTO.txt
+++ b/Documentation/virtual/uml/UserModeLinux-HOWTO.txt
@@ -1182,6 +1182,16 @@
   forge.net/>  and explains these in detail, as well as
   some other issues.
 
+  There is also a related point-to-point only "ucast" transport.
+  This is useful when your network does not support multicast, and
+  all network connections are simple point to point links.
+
+  The full set of command line options for this transport are
+
+
+       ethn=ucast,ethernet address,remote address,listen port,remote port
+
+
 
 
   66..66..  TTUUNN//TTAAPP wwiitthh tthhee uummll__nneett hheellppeerr

arch/um/drivers/Makefile

View file

diff --git a/arch/um/drivers/Makefile b/arch/um/drivers/Makefile
index 1d9b6ae..e7582e1 100644
--- a/arch/um/drivers/Makefile
+++ b/arch/um/drivers/Makefile
@@ -9,7 +9,7 @@
 slip-objs := slip_kern.o slip_user.o
 slirp-objs := slirp_kern.o slirp_user.o
 daemon-objs := daemon_kern.o daemon_user.o
-mcast-objs := mcast_kern.o mcast_user.o
+umcast-objs := umcast_kern.o umcast_user.o
 net-objs := net_kern.o net_user.o
 mconsole-objs := mconsole_kern.o mconsole_user.o
 hostaudio-objs := hostaudio_kern.o
@@ -44,7 +44,7 @@ obj-$(CONFIG_UML_NET_SLIP) += slip.o slip_common.o
 obj-$(CONFIG_UML_NET_SLIRP) += slirp.o slip_common.o
 obj-$(CONFIG_UML_NET_DAEMON) += daemon.o 
 obj-$(CONFIG_UML_NET_VDE) += vde.o
-obj-$(CONFIG_UML_NET_MCAST) += mcast.o 
+obj-$(CONFIG_UML_NET_MCAST) += umcast.o
 obj-$(CONFIG_UML_NET_PCAP) += pcap.o
 obj-$(CONFIG_UML_NET) += net.o 
 obj-$(CONFIG_MCONSOLE) += mconsole.o

arch/um/drivers/mcast.h

View before deletion

diff --git a/arch/um/drivers/mcast.h b/arch/um/drivers/mcast.h
deleted file mode 100644
index 6fa282e..0000000
--- a/arch/um/drivers/mcast.h
+++ /dev/null
@@ -1,24 +0,0 @@
-/* 
- * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
- */
-
-#ifndef __DRIVERS_MCAST_H
-#define __DRIVERS_MCAST_H
-
-#include "net_user.h"
-
-struct mcast_data {
-	char *addr;
-	unsigned short port;
-	void *mcast_addr;
-	int ttl;
-	void *dev;
-};
-
-extern const struct net_user_info mcast_user_info;
-
-extern int mcast_user_write(int fd, void *buf, int len, 
-			    struct mcast_data *pri);
-
-#endif

arch/um/drivers/umcast.h

View file

diff --git a/arch/um/drivers/umcast.h b/arch/um/drivers/umcast.h
new file mode 100644
index 0000000..6f8c0fe
--- /dev/null
+++ b/arch/um/drivers/umcast.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __DRIVERS_UMCAST_H
+#define __DRIVERS_UMCAST_H
+
+#include "net_user.h"
+
+struct umcast_data {
+	char *addr;
+	unsigned short lport;
+	unsigned short rport;
+	void *listen_addr;
+	void *remote_addr;
+	int ttl;
+	int unicast;
+	void *dev;
+};
+
+extern const struct net_user_info umcast_user_info;
+
+extern int umcast_user_write(int fd, void *buf, int len,
+			     struct umcast_data *pri);
+
+#endif

arch/um/drivers/umcast_kern.c

View file

diff --git a/arch/um/drivers/mcast_kern.c b/arch/um/drivers/umcast_kern.c
similarity index 51%
rename from arch/um/drivers/mcast_kern.c
rename to arch/um/drivers/umcast_kern.c
index ffc6416..42dab11 100644
--- a/arch/um/drivers/mcast_kern.c
+++ b/arch/um/drivers/umcast_kern.c
@@ -13,61 +13,70 @@
 
 #include "linux/init.h"
 #include <linux/netdevice.h>
-#include "mcast.h"
+#include "umcast.h"
 #include "net_kern.h"
 
-struct mcast_init {
+struct umcast_init {
 	char *addr;
-	int port;
+	int lport;
+	int rport;
 	int ttl;
+	bool unicast;
 };
 
-static void mcast_init(struct net_device *dev, void *data)
+static void umcast_init(struct net_device *dev, void *data)
 {
 	struct uml_net_private *pri;
-	struct mcast_data *dpri;
-	struct mcast_init *init = data;
+	struct umcast_data *dpri;
+	struct umcast_init *init = data;
 
 	pri = netdev_priv(dev);
-	dpri = (struct mcast_data *) pri->user;
+	dpri = (struct umcast_data *) pri->user;
 	dpri->addr = init->addr;
-	dpri->port = init->port;
+	dpri->lport = init->lport;
+	dpri->rport = init->rport;
+	dpri->unicast = init->unicast;
 	dpri->ttl = init->ttl;
 	dpri->dev = dev;
 
-	printk("mcast backend multicast address: %s:%u, TTL:%u\n",
-	       dpri->addr, dpri->port, dpri->ttl);
+	if (dpri->unicast) {
+		printk(KERN_INFO "ucast backend address: %s:%u listen port: "
+		       "%u\n", dpri->addr, dpri->rport, dpri->lport);
+	} else {
+		printk(KERN_INFO "mcast backend multicast address: %s:%u, "
+		       "TTL:%u\n", dpri->addr, dpri->lport, dpri->ttl);
+	}
 }
 
-static int mcast_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
+static int umcast_read(int fd, struct sk_buff *skb, struct uml_net_private *lp)
 {
 	return net_recvfrom(fd, skb_mac_header(skb),
 			    skb->dev->mtu + ETH_HEADER_OTHER);
 }
 
-static int mcast_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
+static int umcast_write(int fd, struct sk_buff *skb, struct uml_net_private *lp)
 {
-	return mcast_user_write(fd, skb->data, skb->len,
-				(struct mcast_data *) &lp->user);
+	return umcast_user_write(fd, skb->data, skb->len,
+				(struct umcast_data *) &lp->user);
 }
 
-static const struct net_kern_info mcast_kern_info = {
-	.init			= mcast_init,
+static const struct net_kern_info umcast_kern_info = {
+	.init			= umcast_init,
 	.protocol		= eth_protocol,
-	.read			= mcast_read,
-	.write			= mcast_write,
+	.read			= umcast_read,
+	.write			= umcast_write,
 };
 
 static int mcast_setup(char *str, char **mac_out, void *data)
 {
-	struct mcast_init *init = data;
+	struct umcast_init *init = data;
 	char *port_str = NULL, *ttl_str = NULL, *remain;
 	char *last;
 
-	*init = ((struct mcast_init)
-		{ .addr 	= "239.192.168.1",
-		  .port 	= 1102,
-		  .ttl 		= 1 });
+	*init = ((struct umcast_init)
+		{ .addr	= "239.192.168.1",
+		  .lport	= 1102,
+		  .ttl	= 1 });
 
 	remain = split_if_spec(str, mac_out, &init->addr, &port_str, &ttl_str,
 			       NULL);
@@ -78,7 +87,7 @@ static int mcast_setup(char *str, char **mac_out, void *data)
 	}
 
 	if (port_str != NULL) {
-		init->port = simple_strtoul(port_str, &last, 10);
+		init->lport = simple_strtoul(port_str, &last, 10);
 		if ((*last != '\0') || (last == port_str)) {
 			printk(KERN_ERR "mcast_setup - Bad port : '%s'\n",
 			       port_str);
@@ -95,26 +104,85 @@ static int mcast_setup(char *str, char **mac_out, void *data)
 		}
 	}
 
+	init->unicast = false;
+	init->rport = init->lport;
+
 	printk(KERN_INFO "Configured mcast device: %s:%u-%u\n", init->addr,
-	       init->port, init->ttl);
+	       init->lport, init->ttl);
+
+	return 1;
+}
+
+static int ucast_setup(char *str, char **mac_out, void *data)
+{
+	struct umcast_init *init = data;
+	char *lport_str = NULL, *rport_str = NULL, *remain;
+	char *last;
+
+	*init = ((struct umcast_init)
+		{ .addr		= "",
+		  .lport	= 1102,
+		  .rport	= 1102 });
+
+	remain = split_if_spec(str, mac_out, &init->addr,
+			       &lport_str, &rport_str, NULL);
+	if (remain != NULL) {
+		printk(KERN_ERR "ucast_setup - Extra garbage on "
+		       "specification : '%s'\n", remain);
+		return 0;
+	}
+
+	if (lport_str != NULL) {
+		init->lport = simple_strtoul(lport_str, &last, 10);
+		if ((*last != '\0') || (last == lport_str)) {
+			printk(KERN_ERR "ucast_setup - Bad listen port : "
+			       "'%s'\n", lport_str);
+			return 0;
+		}
+	}
+
+	if (rport_str != NULL) {
+		init->rport = simple_strtoul(rport_str, &last, 10);
+		if ((*last != '\0') || (last == rport_str)) {
+			printk(KERN_ERR "ucast_setup - Bad remote port : "
+			       "'%s'\n", rport_str);
+			return 0;
+		}
+	}
+
+	init->unicast = true;
+
+	printk(KERN_INFO "Configured ucast device: :%u -> %s:%u\n",
+	       init->lport, init->addr, init->rport);
 
 	return 1;
 }
 
 static struct transport mcast_transport = {
-	.list 		= LIST_HEAD_INIT(mcast_transport.list),
-	.name 		= "mcast",
-	.setup  	= mcast_setup,
-	.user 		= &mcast_user_info,
-	.kern 		= &mcast_kern_info,
-	.private_size 	= sizeof(struct mcast_data),
-	.setup_size 	= sizeof(struct mcast_init),
+	.list	= LIST_HEAD_INIT(mcast_transport.list),
+	.name	= "mcast",
+	.setup	= mcast_setup,
+	.user	= &umcast_user_info,
+	.kern	= &umcast_kern_info,
+	.private_size	= sizeof(struct umcast_data),
+	.setup_size	= sizeof(struct umcast_init),
+};
+
+static struct transport ucast_transport = {
+	.list	= LIST_HEAD_INIT(ucast_transport.list),
+	.name	= "ucast",
+	.setup	= ucast_setup,
+	.user	= &umcast_user_info,
+	.kern	= &umcast_kern_info,
+	.private_size	= sizeof(struct umcast_data),
+	.setup_size	= sizeof(struct umcast_init),
 };
 
-static int register_mcast(void)
+static int register_umcast(void)
 {
 	register_transport(&mcast_transport);
+	register_transport(&ucast_transport);
 	return 0;
 }
 
-late_initcall(register_mcast);
+late_initcall(register_umcast);

arch/um/drivers/umcast_user.c

View file

diff --git a/arch/um/drivers/mcast_user.c b/arch/um/drivers/umcast_user.c
similarity index 63%
rename from arch/um/drivers/mcast_user.c
rename to arch/um/drivers/umcast_user.c
index ee19e91..59c56fd 100644
--- a/arch/um/drivers/mcast_user.c
+++ b/arch/um/drivers/umcast_user.c
@@ -16,7 +16,7 @@
 #include <errno.h>
 #include <netinet/in.h>
 #include "kern_constants.h"
-#include "mcast.h"
+#include "umcast.h"
 #include "net_user.h"
 #include "um_malloc.h"
 #include "user.h"
@@ -32,93 +32,111 @@ static struct sockaddr_in *new_addr(char *addr, unsigned short port)
 		return NULL;
 	}
 	sin->sin_family = AF_INET;
-	sin->sin_addr.s_addr = in_aton(addr);
+	if (addr)
+		sin->sin_addr.s_addr = in_aton(addr);
+	else
+		sin->sin_addr.s_addr = INADDR_ANY;
 	sin->sin_port = htons(port);
 	return sin;
 }
 
-static int mcast_user_init(void *data, void *dev)
+static int umcast_user_init(void *data, void *dev)
 {
-	struct mcast_data *pri = data;
+	struct umcast_data *pri = data;
 
-	pri->mcast_addr = new_addr(pri->addr, pri->port);
+	pri->remote_addr = new_addr(pri->addr, pri->rport);
+	if (pri->unicast)
+		pri->listen_addr = new_addr(NULL, pri->lport);
+	else
+		pri->listen_addr = pri->remote_addr;
 	pri->dev = dev;
 	return 0;
 }
 
-static void mcast_remove(void *data)
+static void umcast_remove(void *data)
 {
-	struct mcast_data *pri = data;
+	struct umcast_data *pri = data;
 
-	kfree(pri->mcast_addr);
-	pri->mcast_addr = NULL;
+	kfree(pri->listen_addr);
+	if (pri->unicast)
+		kfree(pri->remote_addr);
+	pri->listen_addr = pri->remote_addr = NULL;
 }
 
-static int mcast_open(void *data)
+static int umcast_open(void *data)
 {
-	struct mcast_data *pri = data;
-	struct sockaddr_in *sin = pri->mcast_addr;
+	struct umcast_data *pri = data;
+	struct sockaddr_in *lsin = pri->listen_addr;
+	struct sockaddr_in *rsin = pri->remote_addr;
 	struct ip_mreq mreq;
 	int fd, yes = 1, err = -EINVAL;
 
 
-	if ((sin->sin_addr.s_addr == 0) || (sin->sin_port == 0))
+	if ((!pri->unicast && lsin->sin_addr.s_addr == 0) ||
+	    (rsin->sin_addr.s_addr == 0) ||
+	    (lsin->sin_port == 0) || (rsin->sin_port == 0))
 		goto out;
 
 	fd = socket(AF_INET, SOCK_DGRAM, 0);
 
 	if (fd < 0) {
 		err = -errno;
-		printk(UM_KERN_ERR "mcast_open : data socket failed, "
+		printk(UM_KERN_ERR "umcast_open : data socket failed, "
 		       "errno = %d\n", errno);
 		goto out;
 	}
 
 	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) {
 		err = -errno;
-		printk(UM_KERN_ERR "mcast_open: SO_REUSEADDR failed, "
+		printk(UM_KERN_ERR "umcast_open: SO_REUSEADDR failed, "
 		       "errno = %d\n", errno);
 		goto out_close;
 	}
 
-	/* set ttl according to config */
-	if (setsockopt(fd, SOL_IP, IP_MULTICAST_TTL, &pri->ttl,
-		       sizeof(pri->ttl)) < 0) {
-		err = -errno;
-		printk(UM_KERN_ERR "mcast_open: IP_MULTICAST_TTL failed, "
-		       "error = %d\n", errno);
-		goto out_close;
+	if (!pri->unicast) {
+		/* set ttl according to config */
+		if (setsockopt(fd, SOL_IP, IP_MULTICAST_TTL, &pri->ttl,
+			       sizeof(pri->ttl)) < 0) {
+			err = -errno;
+			printk(UM_KERN_ERR "umcast_open: IP_MULTICAST_TTL "
+			       "failed, error = %d\n", errno);
+			goto out_close;
+		}
+
+		/* set LOOP, so data does get fed back to local sockets */
+		if (setsockopt(fd, SOL_IP, IP_MULTICAST_LOOP,
+			       &yes, sizeof(yes)) < 0) {
+			err = -errno;
+			printk(UM_KERN_ERR "umcast_open: IP_MULTICAST_LOOP "
+			       "failed, error = %d\n", errno);
+			goto out_close;
+		}
 	}
 
-	/* set LOOP, so data does get fed back to local sockets */
-	if (setsockopt(fd, SOL_IP, IP_MULTICAST_LOOP, &yes, sizeof(yes)) < 0) {
+	/* bind socket to the address */
+	if (bind(fd, (struct sockaddr *) lsin, sizeof(*lsin)) < 0) {
 		err = -errno;
-		printk(UM_KERN_ERR "mcast_open: IP_MULTICAST_LOOP failed, "
-		       "error = %d\n", errno);
-		goto out_close;
-	}
-
-	/* bind socket to mcast address */
-	if (bind(fd, (struct sockaddr *) sin, sizeof(*sin)) < 0) {
-		err = -errno;
-		printk(UM_KERN_ERR "mcast_open : data bind failed, "
+		printk(UM_KERN_ERR "umcast_open : data bind failed, "
 		       "errno = %d\n", errno);
 		goto out_close;
 	}
 
-	/* subscribe to the multicast group */
-	mreq.imr_multiaddr.s_addr = sin->sin_addr.s_addr;
-	mreq.imr_interface.s_addr = 0;
-	if (setsockopt(fd, SOL_IP, IP_ADD_MEMBERSHIP,
-		       &mreq, sizeof(mreq)) < 0) {
-		err = -errno;
-		printk(UM_KERN_ERR "mcast_open: IP_ADD_MEMBERSHIP failed, "
-		       "error = %d\n", errno);
-		printk(UM_KERN_ERR "There appears not to be a multicast-"
-		       "capable network interface on the host.\n");
-		printk(UM_KERN_ERR "eth0 should be configured in order to use "
-		       "the multicast transport.\n");
-		goto out_close;
+	if (!pri->unicast) {
+		/* subscribe to the multicast group */
+		mreq.imr_multiaddr.s_addr = lsin->sin_addr.s_addr;
+		mreq.imr_interface.s_addr = 0;
+		if (setsockopt(fd, SOL_IP, IP_ADD_MEMBERSHIP,
+			       &mreq, sizeof(mreq)) < 0) {
+			err = -errno;
+			printk(UM_KERN_ERR "umcast_open: IP_ADD_MEMBERSHIP "
+			       "failed, error = %d\n", errno);
+			printk(UM_KERN_ERR "There appears not to be a "
+			       "multicast-capable network interface on the "
+			       "host.\n");
+			printk(UM_KERN_ERR "eth0 should be configured in order "
+			       "to use the multicast transport.\n");
+			goto out_close;
+		}
 	}
 
 	return fd;
@@ -129,37 +147,40 @@ static int mcast_open(void *data)
 	return err;
 }
 
-static void mcast_close(int fd, void *data)
+static void umcast_close(int fd, void *data)
 {
-	struct ip_mreq mreq;
-	struct mcast_data *pri = data;
-	struct sockaddr_in *sin = pri->mcast_addr;
-
-	mreq.imr_multiaddr.s_addr = sin->sin_addr.s_addr;
-	mreq.imr_interface.s_addr = 0;
-	if (setsockopt(fd, SOL_IP, IP_DROP_MEMBERSHIP,
-		       &mreq, sizeof(mreq)) < 0) {
-		printk(UM_KERN_ERR "mcast_open: IP_DROP_MEMBERSHIP failed, "
-		       "error = %d\n", errno);
+	struct umcast_data *pri = data;
+
+	if (!pri->unicast) {
+		struct ip_mreq mreq;
+		struct sockaddr_in *lsin = pri->listen_addr;
+
+		mreq.imr_multiaddr.s_addr = lsin->sin_addr.s_addr;
+		mreq.imr_interface.s_addr = 0;
+		if (setsockopt(fd, SOL_IP, IP_DROP_MEMBERSHIP,
+			       &mreq, sizeof(mreq)) < 0) {
+			printk(UM_KERN_ERR "umcast_close: IP_DROP_MEMBERSHIP "
+			       "failed, error = %d\n", errno);
+		}
 	}
 
 	close(fd);
 }
 
-int mcast_user_write(int fd, void *buf, int len, struct mcast_data *pri)
+int umcast_user_write(int fd, void *buf, int len, struct umcast_data *pri)
 {
-	struct sockaddr_in *data_addr = pri->mcast_addr;
+	struct sockaddr_in *data_addr = pri->remote_addr;
 
 	return net_sendto(fd, buf, len, data_addr, sizeof(*data_addr));
 }
 
-const struct net_user_info mcast_user_info = {
-	.init		= mcast_user_init,
-	.open		= mcast_open,
-	.close	 	= mcast_close,
-	.remove	 	= mcast_remove,
+const struct net_user_info umcast_user_info = {
+	.init	= umcast_user_init,
+	.open	= umcast_open,
+	.close	= umcast_close,
+	.remove	= umcast_remove,
 	.add_address	= NULL,
 	.delete_address = NULL,
-	.mtu		= ETH_MAX_PACKET,
+	.mtu	= ETH_MAX_PACKET,
 	.max_packet	= ETH_MAX_PACKET + ETH_HEADER_OTHER,
 };