summaryrefslogtreecommitdiff
path: root/arch/um/drivers/port_user.c
blob: 5f56d11b886fc2926ac412b0f3b292a1a88b2ec3 (plain) (blame)
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
/*
 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
 * Licensed under the GPL
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <termios.h>
#include <unistd.h>
#include <netinet/in.h>
#include "chan_user.h"
#include <os.h>
#include "port.h"
#include <um_malloc.h>

struct port_chan {
	int raw;
	struct termios tt;
	void *kernel_data;
	char dev[sizeof("32768\0")];
};

static void *port_init(char *str, int device, const struct chan_opts *opts)
{
	struct port_chan *data;
	void *kern_data;
	char *end;
	int port;

	if (*str != ':') {
		printk(UM_KERN_ERR "port_init : channel type 'port' must "
		       "specify a port number\n");
		return NULL;
	}
	str++;
	port = strtoul(str, &end, 0);
	if ((*end != '\0') || (end == str)) {
		printk(UM_KERN_ERR "port_init : couldn't parse port '%s'\n",
		       str);
		return NULL;
	}

	kern_data = port_data(port);
	if (kern_data == NULL)
		return NULL;

	data = uml_kmalloc(sizeof(*data), UM_GFP_KERNEL);
	if (data == NULL)
		goto err;

	*data = ((struct port_chan) { .raw  		= opts->raw,
				      .kernel_data 	= kern_data });
	sprintf(data->dev, "%d", port);

	return data;
 err:
	port_kern_free(kern_data);
	return NULL;
}

static void port_free(void *d)
{
	struct port_chan *data = d;

	port_kern_free(data->kernel_data);
	kfree(data);
}

static int port_open(int input, int output, int primary, void *d,
		     char **dev_out)
{
	struct port_chan *data = d;
	int fd, err;

	fd = port_wait(data->kernel_data);
	if ((fd >= 0) && data->raw) {
		CATCH_EINTR(err = tcgetattr(fd, &data->tt));
		if (err)
			return err;

		err = raw(fd);
		if (err)
			return err;
	}
	*dev_out = data->dev;
	return fd;
}

static void port_close(int fd, void *d)
{
	struct port_chan *data = d;

	port_remove_dev(data->kernel_data);
	os_close_file(fd);
}

const struct chan_ops port_ops = {
	.type		= "port",
	.init		= port_init,
	.open		= port_open,
	.close		= port_close,
	.read	        = generic_read,
	.write		= generic_write,
	.console_write	= generic_console_write,
	.window_size	= generic_window_size,
	.free		= port_free,
	.winch		= 1,
};

int port_listen_fd(int port)
{
	struct sockaddr_in addr;
	int fd, err, arg;

	fd = socket(PF_INET, SOCK_STREAM, 0);
	if (fd == -1)
		return -errno;

	arg = 1;
	if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &arg, sizeof(arg)) < 0) {
		err = -errno;
		goto out;
	}

	addr.sin_family = AF_INET;
	addr.sin_port = htons(port);
	addr.sin_addr.s_addr = htonl(INADDR_ANY);
	if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
		err = -errno;
		goto out;
	}

	if (listen(fd, 1) < 0) {
		err = -errno;
		goto out;
	}

	err = os_set_fd_block(fd, 0);
	if (err < 0)
		goto out;

	return fd;
 out:
	close(fd);
	return err;
}

struct port_pre_exec_data {
	int sock_fd;
	int pipe_fd;
};

static void port_pre_exec(void *arg)
{
	struct port_pre_exec_data *data = arg;

	dup2(data->sock_fd, 0);
	dup2(data->sock_fd, 1);
	dup2(data->sock_fd, 2);
	close(data->sock_fd);
	dup2(data->pipe_fd, 3);
	shutdown(3, SHUT_RD);
	close(data->pipe_fd);
}

int port_connection(int fd, int *socket, int *pid_out)
{
	int new, err;
	char *argv[] = { "/usr/sbin/in.telnetd", "-L",
			 OS_LIB_PATH "/uml/port-helper", NULL };
	struct port_pre_exec_data data;

	new = accept(fd, NULL, 0);
	if (new < 0)
		return -errno;

	err = os_pipe(socket, 0, 0);
	if (err < 0)
		goto out_close;

	data = ((struct port_pre_exec_data)
		{ .sock_fd  		= new,
		  .pipe_fd 		= socket[1] });

	err = run_helper(port_pre_exec, &data, argv);
	if (err < 0)
		goto out_shutdown;

	*pid_out = err;
	return new;

 out_shutdown:
	shutdown(socket[0], SHUT_RDWR);
	close(socket[0]);
	shutdown(socket[1], SHUT_RDWR);
	close(socket[1]);
 out_close:
	close(new);
	return err;
}