summaryrefslogtreecommitdiff
path: root/arch/um/drivers/slip_user.c
blob: 7334019c9e60a2239b922757888b022891b9dca0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <termios.h>
#include <sys/wait.h>
#include <net_user.h>
#include <os.h>
#include "slip.h"
#include <um_malloc.h>

static int slip_user_init(void *data, void *dev)
{
	struct slip_data *pri = data;

	pri->dev = dev;
	return 0;
}

static int set_up_tty(int fd)
{
	int i;
	struct termios tios;

	if (tcgetattr(fd, &tios) < 0) {
		printk(UM_KERN_ERR "could not get initial terminal "
		       "attributes\n");
		return -1;
	}

	tios.c_cflag = CS8 | CREAD | HUPCL | CLOCAL;
	tios.c_iflag = IGNBRK | IGNPAR;
	tios.c_oflag = 0;
	tios.c_lflag = 0;
	for (i = 0; i < NCCS; i++)
		tios.c_cc[i] = 0;
	tios.c_cc[VMIN] = 1;
	tios.c_cc[VTIME] = 0;

	cfsetospeed(&tios, B38400);
	cfsetispeed(&tios, B38400);

	if (tcsetattr(fd, TCSAFLUSH, &tios) < 0) {
		printk(UM_KERN_ERR "failed to set terminal attributes\n");
		return -1;
	}
	return 0;
}

struct slip_pre_exec_data {
	int stdin_fd;
	int stdout_fd;
	int close_me;
};

static void slip_pre_exec(void *arg)
{
	struct slip_pre_exec_data *data = arg;

	if (data->stdin_fd >= 0)
		dup2(data->stdin_fd, 0);
	dup2(data->stdout_fd, 1);
	if (data->close_me >= 0)
		close(data->close_me);
}

static int slip_tramp(char **argv, int fd)
{
	struct slip_pre_exec_data pe_data;
	char *output;
	int pid, fds[2], err, output_len;

	err = os_pipe(fds, 1, 0);
	if (err < 0) {
		printk(UM_KERN_ERR "slip_tramp : pipe failed, err = %d\n",
		       -err);
		goto out;
	}

	err = 0;
	pe_data.stdin_fd = fd;
	pe_data.stdout_fd = fds[1];
	pe_data.close_me = fds[0];
	err = run_helper(slip_pre_exec, &pe_data, argv);
	if (err < 0)
		goto out_close;
	pid = err;

	output_len = UM_KERN_PAGE_SIZE;
	output = uml_kmalloc(output_len, UM_GFP_KERNEL);
	if (output == NULL) {
		printk(UM_KERN_ERR "slip_tramp : failed to allocate output "
		       "buffer\n");
		os_kill_process(pid, 1);
		err = -ENOMEM;
		goto out_close;
	}

	close(fds[1]);
	read_output(fds[0], output, output_len);
	printk("%s", output);

	err = helper_wait(pid);
	close(fds[0]);

	kfree(output);
	return err;

out_close:
	close(fds[0]);
	close(fds[1]);
out:
	return err;
}

static int slip_open(void *data)
{
	struct slip_data *pri = data;
	char version_buf[sizeof("nnnnn\0")];
	char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
	char *argv[] = { "uml_net", version_buf, "slip", "up", gate_buf,
			 NULL };
	int sfd, mfd, err;

	err = get_pty();
	if (err < 0) {
		printk(UM_KERN_ERR "slip-open : Failed to open pty, err = %d\n",
		       -err);
		goto out;
	}
	mfd = err;

	err = open(ptsname(mfd), O_RDWR, 0);
	if (err < 0) {
		printk(UM_KERN_ERR "Couldn't open tty for slip line, "
		       "err = %d\n", -err);
		goto out_close;
	}
	sfd = err;

	err = set_up_tty(sfd);
	if (err)
		goto out_close2;

	pri->slave = sfd;
	pri->slip.pos = 0;
	pri->slip.esc = 0;
	if (pri->gate_addr != NULL) {
		sprintf(version_buf, "%d", UML_NET_VERSION);
		strcpy(gate_buf, pri->gate_addr);

		err = slip_tramp(argv, sfd);

		if (err < 0) {
			printk(UM_KERN_ERR "slip_tramp failed - err = %d\n",
			       -err);
			goto out_close2;
		}
		err = os_get_ifname(pri->slave, pri->name);
		if (err < 0) {
			printk(UM_KERN_ERR "get_ifname failed, err = %d\n",
			       -err);
			goto out_close2;
		}
		iter_addresses(pri->dev, open_addr, pri->name);
	}
	else {
		err = os_set_slip(sfd);
		if (err < 0) {
			printk(UM_KERN_ERR "Failed to set slip discipline "
			       "encapsulation - err = %d\n", -err);
			goto out_close2;
		}
	}
	return mfd;
out_close2:
	close(sfd);
out_close:
	close(mfd);
out:
	return err;
}

static void slip_close(int fd, void *data)
{
	struct slip_data *pri = data;
	char version_buf[sizeof("nnnnn\0")];
	char *argv[] = { "uml_net", version_buf, "slip", "down", pri->name,
			 NULL };
	int err;

	if (pri->gate_addr != NULL)
		iter_addresses(pri->dev, close_addr, pri->name);

	sprintf(version_buf, "%d", UML_NET_VERSION);

	err = slip_tramp(argv, pri->slave);

	if (err != 0)
		printk(UM_KERN_ERR "slip_tramp failed - errno = %d\n", -err);
	close(fd);
	close(pri->slave);
	pri->slave = -1;
}

int slip_user_read(int fd, void *buf, int len, struct slip_data *pri)
{
	return slip_proto_read(fd, buf, len, &pri->slip);
}

int slip_user_write(int fd, void *buf, int len, struct slip_data *pri)
{
	return slip_proto_write(fd, buf, len, &pri->slip);
}

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

	if (pri->slave < 0)
		return;
	open_addr(addr, netmask, pri->name);
}

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

	if (pri->slave < 0)
		return;
	close_addr(addr, netmask, pri->name);
}

const struct net_user_info slip_user_info = {
	.init		= slip_user_init,
	.open		= slip_open,
	.close	 	= slip_close,
	.remove	 	= NULL,
	.add_address	= slip_add_addr,
	.delete_address = slip_del_addr,
	.mtu		= BUF_SIZE,
	.max_packet	= BUF_SIZE,
};