xref: /openbmc/linux/arch/um/drivers/port_user.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * Copyright (C) 2001 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  */
5 
6 #include <stdio.h>
7 #include <stddef.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <errno.h>
11 #include <unistd.h>
12 #include <termios.h>
13 #include <sys/socket.h>
14 #include <sys/un.h>
15 #include <netinet/in.h>
16 #include "user_util.h"
17 #include "kern_util.h"
18 #include "user.h"
19 #include "chan_user.h"
20 #include "port.h"
21 #include "helper.h"
22 #include "os.h"
23 
24 struct port_chan {
25 	int raw;
26 	struct termios tt;
27 	void *kernel_data;
28 	char dev[sizeof("32768\0")];
29 };
30 
31 static void *port_init(char *str, int device, struct chan_opts *opts)
32 {
33 	struct port_chan *data;
34 	void *kern_data;
35 	char *end;
36 	int port;
37 
38 	if(*str != ':'){
39 		printk("port_init : channel type 'port' must specify a "
40 		       "port number\n");
41 		return(NULL);
42 	}
43 	str++;
44 	port = strtoul(str, &end, 0);
45 	if((*end != '\0') || (end == str)){
46 		printk("port_init : couldn't parse port '%s'\n", str);
47 		return(NULL);
48 	}
49 
50 	kern_data = port_data(port);
51 	if(kern_data == NULL)
52 		return(NULL);
53 
54 	data = um_kmalloc(sizeof(*data));
55 	if(data == NULL)
56 		goto err;
57 
58 	*data = ((struct port_chan) { .raw  		= opts->raw,
59 				      .kernel_data 	= kern_data });
60 	sprintf(data->dev, "%d", port);
61 
62 	return(data);
63  err:
64 	port_kern_free(kern_data);
65 	return(NULL);
66 }
67 
68 static void port_free(void *d)
69 {
70 	struct port_chan *data = d;
71 
72 	port_kern_free(data->kernel_data);
73 	kfree(data);
74 }
75 
76 static int port_open(int input, int output, int primary, void *d,
77 		     char **dev_out)
78 {
79 	struct port_chan *data = d;
80 	int fd, err;
81 
82 	fd = port_wait(data->kernel_data);
83 	if((fd >= 0) && data->raw){
84 		CATCH_EINTR(err = tcgetattr(fd, &data->tt));
85 		if(err)
86 			return(err);
87 
88 		err = raw(fd);
89 		if(err)
90 			return(err);
91 	}
92 	*dev_out = data->dev;
93 	return(fd);
94 }
95 
96 static void port_close(int fd, void *d)
97 {
98 	struct port_chan *data = d;
99 
100 	port_remove_dev(data->kernel_data);
101 	os_close_file(fd);
102 }
103 
104 static int port_console_write(int fd, const char *buf, int n, void *d)
105 {
106 	struct port_chan *data = d;
107 
108 	return(generic_console_write(fd, buf, n, &data->tt));
109 }
110 
111 struct chan_ops port_ops = {
112 	.type		= "port",
113 	.init		= port_init,
114 	.open		= port_open,
115 	.close		= port_close,
116 	.read	        = generic_read,
117 	.write		= generic_write,
118 	.console_write	= port_console_write,
119 	.window_size	= generic_window_size,
120 	.free		= port_free,
121 	.winch		= 1,
122 };
123 
124 int port_listen_fd(int port)
125 {
126 	struct sockaddr_in addr;
127 	int fd, err, arg;
128 
129 	fd = socket(PF_INET, SOCK_STREAM, 0);
130 	if(fd == -1)
131 		return(-errno);
132 
133 	arg = 1;
134 	if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &arg, sizeof(arg)) < 0){
135 		err = -errno;
136 		goto out;
137 	}
138 
139 	addr.sin_family = AF_INET;
140 	addr.sin_port = htons(port);
141 	addr.sin_addr.s_addr = htonl(INADDR_ANY);
142 	if(bind(fd, (struct sockaddr *) &addr, sizeof(addr)) < 0){
143 		err = -errno;
144 		goto out;
145 	}
146 
147 	if(listen(fd, 1) < 0){
148 		err = -errno;
149 		goto out;
150 	}
151 
152 	err = os_set_fd_block(fd, 0);
153 	if(err < 0)
154 		goto out;
155 
156 	return(fd);
157  out:
158 	os_close_file(fd);
159 	return(err);
160 }
161 
162 struct port_pre_exec_data {
163 	int sock_fd;
164 	int pipe_fd;
165 };
166 
167 void port_pre_exec(void *arg)
168 {
169 	struct port_pre_exec_data *data = arg;
170 
171 	dup2(data->sock_fd, 0);
172 	dup2(data->sock_fd, 1);
173 	dup2(data->sock_fd, 2);
174 	os_close_file(data->sock_fd);
175 	dup2(data->pipe_fd, 3);
176 	os_shutdown_socket(3, 1, 0);
177 	os_close_file(data->pipe_fd);
178 }
179 
180 int port_connection(int fd, int *socket, int *pid_out)
181 {
182 	int new, err;
183 	char *argv[] = { "/usr/sbin/in.telnetd", "-L",
184 			 "/usr/lib/uml/port-helper", NULL };
185 	struct port_pre_exec_data data;
186 
187 	new = os_accept_connection(fd);
188 	if(new < 0)
189 		return(new);
190 
191 	err = os_pipe(socket, 0, 0);
192 	if(err < 0)
193 		goto out_close;
194 
195 	data = ((struct port_pre_exec_data)
196 		{ .sock_fd  		= new,
197 		  .pipe_fd 		= socket[1] });
198 
199 	err = run_helper(port_pre_exec, &data, argv, NULL);
200 	if(err < 0)
201 		goto out_shutdown;
202 
203 	*pid_out = err;
204 	return(new);
205 
206  out_shutdown:
207 	os_shutdown_socket(socket[0], 1, 1);
208 	os_close_file(socket[0]);
209 	os_shutdown_socket(socket[1], 1, 1);
210 	os_close_file(socket[1]);
211  out_close:
212 	os_close_file(new);
213 	return(err);
214 }
215 
216 /*
217  * Overrides for Emacs so that we follow Linus's tabbing style.
218  * Emacs will notice this stuff at the end of the file and automatically
219  * adjust the settings for this buffer only.  This must remain at the end
220  * of the file.
221  * ---------------------------------------------------------------------------
222  * Local variables:
223  * c-file-style: "linux"
224  * End:
225  */
226