xref: /openbmc/linux/arch/um/drivers/slip_user.c (revision 87c2ce3b)
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <unistd.h>
4 #include <stddef.h>
5 #include <sched.h>
6 #include <string.h>
7 #include <errno.h>
8 #include <sys/termios.h>
9 #include <sys/wait.h>
10 #include <sys/signal.h>
11 #include "user_util.h"
12 #include "kern_util.h"
13 #include "user.h"
14 #include "net_user.h"
15 #include "slip.h"
16 #include "slip_common.h"
17 #include "os.h"
18 
19 void slip_user_init(void *data, void *dev)
20 {
21 	struct slip_data *pri = data;
22 
23 	pri->dev = dev;
24 }
25 
26 static int set_up_tty(int fd)
27 {
28 	int i;
29 	struct termios tios;
30 
31 	if (tcgetattr(fd, &tios) < 0) {
32 		printk("could not get initial terminal attributes\n");
33 		return(-1);
34 	}
35 
36 	tios.c_cflag = CS8 | CREAD | HUPCL | CLOCAL;
37 	tios.c_iflag = IGNBRK | IGNPAR;
38 	tios.c_oflag = 0;
39 	tios.c_lflag = 0;
40 	for (i = 0; i < NCCS; i++)
41 		tios.c_cc[i] = 0;
42 	tios.c_cc[VMIN] = 1;
43 	tios.c_cc[VTIME] = 0;
44 
45 	cfsetospeed(&tios, B38400);
46 	cfsetispeed(&tios, B38400);
47 
48 	if (tcsetattr(fd, TCSAFLUSH, &tios) < 0) {
49 		printk("failed to set terminal attributes\n");
50 		return(-1);
51 	}
52 	return(0);
53 }
54 
55 struct slip_pre_exec_data {
56 	int stdin;
57 	int stdout;
58 	int close_me;
59 };
60 
61 static void slip_pre_exec(void *arg)
62 {
63 	struct slip_pre_exec_data *data = arg;
64 
65 	if(data->stdin >= 0) dup2(data->stdin, 0);
66 	dup2(data->stdout, 1);
67 	if(data->close_me >= 0) os_close_file(data->close_me);
68 }
69 
70 static int slip_tramp(char **argv, int fd)
71 {
72 	struct slip_pre_exec_data pe_data;
73 	char *output;
74 	int status, pid, fds[2], err, output_len;
75 
76 	err = os_pipe(fds, 1, 0);
77 	if(err < 0){
78 		printk("slip_tramp : pipe failed, err = %d\n", -err);
79 		goto out;
80 	}
81 
82 	err = 0;
83 	pe_data.stdin = fd;
84 	pe_data.stdout = fds[1];
85 	pe_data.close_me = fds[0];
86 	err = run_helper(slip_pre_exec, &pe_data, argv, NULL);
87 	if(err < 0)
88 		goto out_close;
89 	pid = err;
90 
91 	output_len = page_size();
92 	output = um_kmalloc(output_len);
93 	if(output == NULL){
94 		printk("slip_tramp : failed to allocate output buffer\n");
95 		os_kill_process(pid, 1);
96 		err = -ENOMEM;
97 		goto out_free;
98 	}
99 
100 	os_close_file(fds[1]);
101 	read_output(fds[0], output, output_len);
102 	printk("%s", output);
103 
104 	CATCH_EINTR(err = waitpid(pid, &status, 0));
105 	if(err < 0)
106 		err = errno;
107 	else if(!WIFEXITED(status) || (WEXITSTATUS(status) != 0)){
108 		printk("'%s' didn't exit with status 0\n", argv[0]);
109 		err = -EINVAL;
110 	}
111 	else err = 0;
112 
113 	os_close_file(fds[0]);
114 
115 out_free:
116 	kfree(output);
117 	return err;
118 
119 out_close:
120 	os_close_file(fds[0]);
121 	os_close_file(fds[1]);
122 out:
123 	return err;
124 }
125 
126 static int slip_open(void *data)
127 {
128 	struct slip_data *pri = data;
129 	char version_buf[sizeof("nnnnn\0")];
130 	char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
131 	char *argv[] = { "uml_net", version_buf, "slip", "up", gate_buf,
132 			 NULL };
133 	int sfd, mfd, err;
134 
135 	err = get_pty();
136 	if(err < 0){
137 		printk("slip-open : Failed to open pty, err = %d\n", -err);
138 		goto out;
139 	}
140 	mfd = err;
141 
142 	err = os_open_file(ptsname(mfd), of_rdwr(OPENFLAGS()), 0);
143 	if(err < 0){
144 		printk("Couldn't open tty for slip line, err = %d\n", -err);
145 		goto out_close;
146 	}
147 	sfd = err;
148 
149 	if(set_up_tty(sfd))
150 		goto out_close2;
151 
152 	pri->slave = sfd;
153 	pri->slip.pos = 0;
154 	pri->slip.esc = 0;
155 	if(pri->gate_addr != NULL){
156 		sprintf(version_buf, "%d", UML_NET_VERSION);
157 		strcpy(gate_buf, pri->gate_addr);
158 
159 		err = slip_tramp(argv, sfd);
160 
161 		if(err < 0){
162 			printk("slip_tramp failed - err = %d\n", -err);
163 			goto out_close2;
164 		}
165 		err = os_get_ifname(pri->slave, pri->name);
166 		if(err < 0){
167 			printk("get_ifname failed, err = %d\n", -err);
168 			goto out_close2;
169 		}
170 		iter_addresses(pri->dev, open_addr, pri->name);
171 	}
172 	else {
173 		err = os_set_slip(sfd);
174 		if(err < 0){
175 			printk("Failed to set slip discipline encapsulation - "
176 			       "err = %d\n", -err);
177 			goto out_close2;
178 		}
179 	}
180 	return(mfd);
181 out_close2:
182 	os_close_file(sfd);
183 out_close:
184 	os_close_file(mfd);
185 out:
186 	return err;
187 }
188 
189 static void slip_close(int fd, void *data)
190 {
191 	struct slip_data *pri = data;
192 	char version_buf[sizeof("nnnnn\0")];
193 	char *argv[] = { "uml_net", version_buf, "slip", "down", pri->name,
194 			 NULL };
195 	int err;
196 
197 	if(pri->gate_addr != NULL)
198 		iter_addresses(pri->dev, close_addr, pri->name);
199 
200 	sprintf(version_buf, "%d", UML_NET_VERSION);
201 
202 	err = slip_tramp(argv, pri->slave);
203 
204 	if(err != 0)
205 		printk("slip_tramp failed - errno = %d\n", -err);
206 	os_close_file(fd);
207 	os_close_file(pri->slave);
208 	pri->slave = -1;
209 }
210 
211 int slip_user_read(int fd, void *buf, int len, struct slip_data *pri)
212 {
213 	return slip_proto_read(fd, buf, len, &pri->slip);
214 }
215 
216 int slip_user_write(int fd, void *buf, int len, struct slip_data *pri)
217 {
218 	return slip_proto_write(fd, buf, len, &pri->slip);
219 }
220 
221 static int slip_set_mtu(int mtu, void *data)
222 {
223 	return(mtu);
224 }
225 
226 static void slip_add_addr(unsigned char *addr, unsigned char *netmask,
227 			  void *data)
228 {
229 	struct slip_data *pri = data;
230 
231 	if(pri->slave < 0) return;
232 	open_addr(addr, netmask, pri->name);
233 }
234 
235 static void slip_del_addr(unsigned char *addr, unsigned char *netmask,
236 			    void *data)
237 {
238 	struct slip_data *pri = data;
239 
240 	if(pri->slave < 0) return;
241 	close_addr(addr, netmask, pri->name);
242 }
243 
244 struct net_user_info slip_user_info = {
245 	.init		= slip_user_init,
246 	.open		= slip_open,
247 	.close	 	= slip_close,
248 	.remove	 	= NULL,
249 	.set_mtu	= slip_set_mtu,
250 	.add_address	= slip_add_addr,
251 	.delete_address = slip_del_addr,
252 	.max_packet	= BUF_SIZE
253 };
254