[mirror_ubuntu-artful-kernel.git] / arch / um / os-Linux / drivers / ethertap_user.c

/*
 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
 * James Leu (jleu@mindspring.net).
 * Copyright (C) 2001 by various other people who didn't put their name here.
 * Licensed under the GPL.
 */

#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include "etap.h"
#include "kern_constants.h"
#include "os.h"
#include "net_user.h"
#include "um_malloc.h"
#include "user.h"

#define MAX_PACKET ETH_MAX_PACKET

static int etap_user_init(void *data, void *dev)
{
	struct ethertap_data *pri = data;

	pri->dev = dev;
	return 0;
}

struct addr_change {
	enum { ADD_ADDR, DEL_ADDR } what;
	unsigned char addr[4];
	unsigned char netmask[4];
};

static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
			int fd)
{
	struct addr_change change;
	char *output;
	int n;

	change.what = op;
	memcpy(change.addr, addr, sizeof(change.addr));
	memcpy(change.netmask, netmask, sizeof(change.netmask));
	CATCH_EINTR(n = write(fd, &change, sizeof(change)));
	if (n != sizeof(change)) {
		printk(UM_KERN_ERR "etap_change - request failed, err = %d\n",
		       errno);
		return;
	}

	output = kmalloc(UM_KERN_PAGE_SIZE, UM_GFP_KERNEL);
	if (output == NULL)
		printk(UM_KERN_ERR "etap_change : Failed to allocate output "
		       "buffer\n");
	read_output(fd, output, UM_KERN_PAGE_SIZE);
	if (output != NULL) {
		printk("%s", output);
		kfree(output);
	}
}

static void etap_open_addr(unsigned char *addr, unsigned char *netmask,
			   void *arg)
{
	etap_change(ADD_ADDR, addr, netmask, *((int *) arg));
}

static void etap_close_addr(unsigned char *addr, unsigned char *netmask,
			    void *arg)
{
	etap_change(DEL_ADDR, addr, netmask, *((int *) arg));
}

struct etap_pre_exec_data {
	int control_remote;
	int control_me;
	int data_me;
};

static void etap_pre_exec(void *arg)
{
	struct etap_pre_exec_data *data = arg;

	dup2(data->control_remote, 1);
	close(data->data_me);
	close(data->control_me);
}

static int etap_tramp(char *dev, char *gate, int control_me,
		      int control_remote, int data_me, int data_remote)
{
	struct etap_pre_exec_data pe_data;
	int pid, status, err, n;
	char version_buf[sizeof("nnnnn\0")];
	char data_fd_buf[sizeof("nnnnnn\0")];
	char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
	char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
			       data_fd_buf, gate_buf, NULL };
	char *nosetup_args[] = { "uml_net", version_buf, "ethertap",
				 dev, data_fd_buf, NULL };
	char **args, c;

	sprintf(data_fd_buf, "%d", data_remote);
	sprintf(version_buf, "%d", UML_NET_VERSION);
	if (gate != NULL) {
		strcpy(gate_buf, gate);
		args = setup_args;
	}
	else args = nosetup_args;

	err = 0;
	pe_data.control_remote = control_remote;
	pe_data.control_me = control_me;
	pe_data.data_me = data_me;
	pid = run_helper(etap_pre_exec, &pe_data, args);

	if (pid < 0)
		err = pid;
	close(data_remote);
	close(control_remote);
	CATCH_EINTR(n = read(control_me, &c, sizeof(c)));
	if (n != sizeof(c)) {
		err = -errno;
		printk(UM_KERN_ERR "etap_tramp : read of status failed, "
		       "err = %d\n", -err);
		return err;
	}
	if (c != 1) {
		printk(UM_KERN_ERR "etap_tramp : uml_net failed\n");
		err = -EINVAL;
		CATCH_EINTR(n = waitpid(pid, &status, 0));
		if (n < 0)
			err = -errno;
		else if (!WIFEXITED(status) || (WEXITSTATUS(status) != 1))
			printk(UM_KERN_ERR "uml_net didn't exit with "
			       "status 1\n");
	}
	return err;
}

static int etap_open(void *data)
{
	struct ethertap_data *pri = data;
	char *output;
	int data_fds[2], control_fds[2], err, output_len;

	err = tap_open_common(pri->dev, pri->gate_addr);
	if (err)
		return err;

	err = socketpair(AF_UNIX, SOCK_DGRAM, 0, data_fds);
	if (err) {
		err = -errno;
		printk(UM_KERN_ERR "etap_open - data socketpair failed - "
		       "err = %d\n", errno);
		return err;
	}

	err = socketpair(AF_UNIX, SOCK_STREAM, 0, control_fds);
	if (err) {
		err = -errno;
		printk(UM_KERN_ERR "etap_open - control socketpair failed - "
		       "err = %d\n", errno);
		goto out_close_data;
	}

	err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0],
			 control_fds[1], data_fds[0], data_fds[1]);
	output_len = UM_KERN_PAGE_SIZE;
	output = kmalloc(output_len, UM_GFP_KERNEL);
	read_output(control_fds[0], output, output_len);

	if (output == NULL)
		printk(UM_KERN_ERR "etap_open : failed to allocate output "
		       "buffer\n");
	else {
		printk("%s", output);
		kfree(output);
	}

	if (err < 0) {
		printk(UM_KERN_ERR "etap_tramp failed - err = %d\n", -err);
		goto out_close_control;
	}

	pri->data_fd = data_fds[0];
	pri->control_fd = control_fds[0];
	iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
	return data_fds[0];

out_close_control:
	close(control_fds[0]);
	close(control_fds[1]);
out_close_data:
	close(data_fds[0]);
	close(data_fds[1]);
	return err;
}

static void etap_close(int fd, void *data)
{
	struct ethertap_data *pri = data;

	iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
	close(fd);

	if (shutdown(pri->data_fd, SHUT_RDWR) < 0)
		printk(UM_KERN_ERR "etap_close - shutdown data socket failed, "
		       "errno = %d\n", errno);

	if (shutdown(pri->control_fd, SHUT_RDWR) < 0)
		printk(UM_KERN_ERR "etap_close - shutdown control socket "
		       "failed, errno = %d\n", errno);

	close(pri->data_fd);
	pri->data_fd = -1;
	close(pri->control_fd);
	pri->control_fd = -1;
}

static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
			  void *data)
{
	struct ethertap_data *pri = data;

	tap_check_ips(pri->gate_addr, addr);
	if (pri->control_fd == -1)
		return;
	etap_open_addr(addr, netmask, &pri->control_fd);
}

static void etap_del_addr(unsigned char *addr, unsigned char *netmask,
			  void *data)
{
	struct ethertap_data *pri = data;

	if (pri->control_fd == -1)
		return;

	etap_close_addr(addr, netmask, &pri->control_fd);
}

const struct net_user_info ethertap_user_info = {
	.init		= etap_user_init,
	.open		= etap_open,
	.close	 	= etap_close,
	.remove	 	= NULL,
	.add_address	= etap_add_addr,
	.delete_address = etap_del_addr,
	.mtu		= ETH_MAX_PACKET,
	.max_packet	= ETH_MAX_PACKET + ETH_HEADER_ETHERTAP,
};
Commit	Line	Data
1da177e4	1	/*
cd1ae0e4	2	* Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
ef0470c0	3	* Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
1da177e4 LT	4	* James Leu (jleu@mindspring.net).
	5	* Copyright (C) 2001 by various other people who didn't put their name here.
	6	* Licensed under the GPL.
	7	*/
	8
	9	#include <stdio.h>
	10	#include <unistd.h>
cd1ae0e4 JD	11	#include <errno.h>
cd1ae0e4 JD	12	#include <string.h>
1da177e4 LT	13	#include <sys/socket.h>
1da177e4 LT	14	#include <sys/wait.h>
1da177e4	15	#include "etap.h"
cd1ae0e4	16	#include "kern_constants.h"
1da177e4	17	#include "os.h"
cd1ae0e4	18	#include "net_user.h"
c13e5690	19	#include "um_malloc.h"
cd1ae0e4	20	#include "user.h"
1da177e4 LT	21
	22	#define MAX_PACKET ETH_MAX_PACKET
	23
f34d9d2d	24	static int etap_user_init(void data, void dev)
1da177e4 LT	25	{
	26	struct ethertap_data *pri = data;
	27
	28	pri->dev = dev;
f34d9d2d	29	return 0;
1da177e4 LT	30	}
	31
	32	struct addr_change {
	33	enum { ADD_ADDR, DEL_ADDR } what;
	34	unsigned char addr[4];
	35	unsigned char netmask[4];
	36	};
	37
	38	static void etap_change(int op, unsigned char addr, unsigned char netmask,
	39	int fd)
	40	{
	41	struct addr_change change;
802e3077	42	char *output;
1da177e4 LT	43	int n;
	44
	45	change.what = op;
	46	memcpy(change.addr, addr, sizeof(change.addr));
	47	memcpy(change.netmask, netmask, sizeof(change.netmask));
a61f334f	48	CATCH_EINTR(n = write(fd, &change, sizeof(change)));
cd1ae0e4 JD	49	if (n != sizeof(change)) {
	50	printk(UM_KERN_ERR "etap_change - request failed, err = %d\n",
	51	errno);
ef0470c0 JD	52	return;
	53	}
	54
e4c4bf99	55	output = kmalloc(UM_KERN_PAGE_SIZE, UM_GFP_KERNEL);
cd1ae0e4 JD	56	if (output == NULL)
	57	printk(UM_KERN_ERR "etap_change : Failed to allocate output "
	58	"buffer\n");
1ffb9164	59	read_output(fd, output, UM_KERN_PAGE_SIZE);
cd1ae0e4	60	if (output != NULL) {
1da177e4 LT	61	printk("%s", output);
	62	kfree(output);
	63	}
	64	}
	65
	66	static void etap_open_addr(unsigned char addr, unsigned char netmask,
	67	void *arg)
	68	{
	69	etap_change(ADD_ADDR, addr, netmask, ((int ) arg));
	70	}
	71
	72	static void etap_close_addr(unsigned char addr, unsigned char netmask,
	73	void *arg)
	74	{
	75	etap_change(DEL_ADDR, addr, netmask, ((int ) arg));
	76	}
	77
	78	struct etap_pre_exec_data {
	79	int control_remote;
	80	int control_me;
	81	int data_me;
	82	};
	83
	84	static void etap_pre_exec(void *arg)
	85	{
	86	struct etap_pre_exec_data *data = arg;
	87
	88	dup2(data->control_remote, 1);
512b6fb1 JD	89	close(data->data_me);
512b6fb1 JD	90	close(data->control_me);
1da177e4 LT	91	}
1da177e4 LT	92
512b6fb1	93	static int etap_tramp(char dev, char gate, int control_me,
1da177e4 LT	94	int control_remote, int data_me, int data_remote)
	95	{
	96	struct etap_pre_exec_data pe_data;
	97	int pid, status, err, n;
	98	char version_buf[sizeof("nnnnn\0")];
	99	char data_fd_buf[sizeof("nnnnnn\0")];
	100	char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
	101	char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
	102	data_fd_buf, gate_buf, NULL };
512b6fb1	103	char *nosetup_args[] = { "uml_net", version_buf, "ethertap",
1da177e4 LT	104	dev, data_fd_buf, NULL };
	105	char **args, c;
	106
	107	sprintf(data_fd_buf, "%d", data_remote);
	108	sprintf(version_buf, "%d", UML_NET_VERSION);
cd1ae0e4	109	if (gate != NULL) {
1da177e4 LT	110	strcpy(gate_buf, gate);
	111	args = setup_args;
	112	}
	113	else args = nosetup_args;
	114
	115	err = 0;
	116	pe_data.control_remote = control_remote;
	117	pe_data.control_me = control_me;
	118	pe_data.data_me = data_me;
c4399016	119	pid = run_helper(etap_pre_exec, &pe_data, args);
1da177e4	120
cd1ae0e4	121	if (pid < 0)
ef0470c0	122	err = pid;
512b6fb1 JD	123	close(data_remote);
512b6fb1 JD	124	close(control_remote);
a61f334f	125	CATCH_EINTR(n = read(control_me, &c, sizeof(c)));
cd1ae0e4	126	if (n != sizeof(c)) {
a61f334f	127	err = -errno;
cd1ae0e4 JD	128	printk(UM_KERN_ERR "etap_tramp : read of status failed, "
cd1ae0e4 JD	129	"err = %d\n", -err);
a61f334f	130	return err;
1da177e4	131	}
cd1ae0e4 JD	132	if (c != 1) {
cd1ae0e4 JD	133	printk(UM_KERN_ERR "etap_tramp : uml_net failed\n");
1da177e4 LT	134	err = -EINVAL;
1da177e4 LT	135	CATCH_EINTR(n = waitpid(pid, &status, 0));
cd1ae0e4	136	if (n < 0)
1da177e4	137	err = -errno;
cd1ae0e4 JD	138	else if (!WIFEXITED(status) \|\| (WEXITSTATUS(status) != 1))
	139	printk(UM_KERN_ERR "uml_net didn't exit with "
	140	"status 1\n");
1da177e4	141	}
56bd194b	142	return err;
1da177e4 LT	143	}
	144
	145	static int etap_open(void *data)
	146	{
	147	struct ethertap_data *pri = data;
	148	char *output;
	149	int data_fds[2], control_fds[2], err, output_len;
	150
	151	err = tap_open_common(pri->dev, pri->gate_addr);
cd1ae0e4	152	if (err)
56bd194b	153	return err;
1da177e4	154
512b6fb1	155	err = socketpair(AF_UNIX, SOCK_DGRAM, 0, data_fds);
cd1ae0e4	156	if (err) {
512b6fb1	157	err = -errno;
cd1ae0e4 JD	158	printk(UM_KERN_ERR "etap_open - data socketpair failed - "
cd1ae0e4 JD	159	"err = %d\n", errno);
56bd194b	160	return err;
1da177e4 LT	161	}
1da177e4 LT	162
512b6fb1	163	err = socketpair(AF_UNIX, SOCK_STREAM, 0, control_fds);
cd1ae0e4	164	if (err) {
512b6fb1	165	err = -errno;
cd1ae0e4 JD	166	printk(UM_KERN_ERR "etap_open - control socketpair failed - "
cd1ae0e4 JD	167	"err = %d\n", errno);
512b6fb1	168	goto out_close_data;
1da177e4	169	}
56bd194b	170
512b6fb1	171	err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0],
1da177e4	172	control_fds[1], data_fds[0], data_fds[1]);
1ffb9164	173	output_len = UM_KERN_PAGE_SIZE;
e4c4bf99	174	output = kmalloc(output_len, UM_GFP_KERNEL);
1da177e4 LT	175	read_output(control_fds[0], output, output_len);
1da177e4 LT	176
cd1ae0e4 JD	177	if (output == NULL)
	178	printk(UM_KERN_ERR "etap_open : failed to allocate output "
	179	"buffer\n");
1da177e4 LT	180	else {
	181	printk("%s", output);
	182	kfree(output);
	183	}
	184
cd1ae0e4 JD	185	if (err < 0) {
cd1ae0e4 JD	186	printk(UM_KERN_ERR "etap_tramp failed - err = %d\n", -err);
512b6fb1	187	goto out_close_control;
1da177e4 LT	188	}
	189
	190	pri->data_fd = data_fds[0];
	191	pri->control_fd = control_fds[0];
	192	iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
56bd194b	193	return data_fds[0];
512b6fb1 JD	194
	195	out_close_control:
	196	close(control_fds[0]);
	197	close(control_fds[1]);
	198	out_close_data:
	199	close(data_fds[0]);
	200	close(data_fds[1]);
	201	return err;
1da177e4 LT	202	}
	203
	204	static void etap_close(int fd, void *data)
	205	{
	206	struct ethertap_data *pri = data;
	207
	208	iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
512b6fb1 JD	209	close(fd);
512b6fb1 JD	210
cd1ae0e4 JD	211	if (shutdown(pri->data_fd, SHUT_RDWR) < 0)
cd1ae0e4 JD	212	printk(UM_KERN_ERR "etap_close - shutdown data socket failed, "
512b6fb1 JD	213	"errno = %d\n", errno);
512b6fb1 JD	214
cd1ae0e4 JD	215	if (shutdown(pri->control_fd, SHUT_RDWR) < 0)
	216	printk(UM_KERN_ERR "etap_close - shutdown control socket "
	217	"failed, errno = %d\n", errno);
	218
512b6fb1	219	close(pri->data_fd);
1da177e4	220	pri->data_fd = -1;
512b6fb1	221	close(pri->control_fd);
1da177e4 LT	222	pri->control_fd = -1;
	223	}
	224
1da177e4 LT	225	static void etap_add_addr(unsigned char addr, unsigned char netmask,
	226	void *data)
	227	{
	228	struct ethertap_data *pri = data;
	229
	230	tap_check_ips(pri->gate_addr, addr);
cd1ae0e4	231	if (pri->control_fd == -1)
56bd194b	232	return;
1da177e4 LT	233	etap_open_addr(addr, netmask, &pri->control_fd);
	234	}
	235
512b6fb1	236	static void etap_del_addr(unsigned char addr, unsigned char netmask,
1da177e4 LT	237	void *data)
	238	{
	239	struct ethertap_data *pri = data;
	240
cd1ae0e4	241	if (pri->control_fd == -1)
56bd194b	242	return;
512b6fb1	243
1da177e4 LT	244	etap_close_addr(addr, netmask, &pri->control_fd);
	245	}
	246
5e7672ec	247	const struct net_user_info ethertap_user_info = {
1da177e4 LT	248	.init = etap_user_init,
	249	.open = etap_open,
	250	.close = etap_close,
	251	.remove = NULL,
1da177e4 LT	252	.add_address = etap_add_addr,
1da177e4 LT	253	.delete_address = etap_del_addr,
b53f35a8 JD	254	.mtu = ETH_MAX_PACKET,
b53f35a8 JD	255	.max_packet = ETH_MAX_PACKET + ETH_HEADER_ETHERTAP,
1da177e4	256	};