1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 */
5
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <unistd.h>
9 #include <errno.h>
10 #include <fcntl.h>
11 #include <string.h>
12 #include <termios.h>
13 #include <sys/wait.h>
14 #include <net_user.h>
15 #include <os.h>
16 #include "slip.h"
17 #include <um_malloc.h>
18
19 static int slip_user_init(void *data, void *dev)
20 {
21 struct slip_data *pri = data;
22
23 pri->dev = dev;
24 return 0;
25 }
26
27 static int set_up_tty(int fd)
28 {
29 int i;
30 struct termios tios;
31
32 if (tcgetattr(fd, &tios) < 0) {
33 printk(UM_KERN_ERR "could not get initial terminal "
34 "attributes\n");
35 return -1;
36 }
37
38 tios.c_cflag = CS8 | CREAD | HUPCL | CLOCAL;
39 tios.c_iflag = IGNBRK | IGNPAR;
40 tios.c_oflag = 0;
41 tios.c_lflag = 0;
42 for (i = 0; i < NCCS; i++)
43 tios.c_cc[i] = 0;
44 tios.c_cc[VMIN] = 1;
45 tios.c_cc[VTIME] = 0;
46
47 cfsetospeed(&tios, B38400);
48 cfsetispeed(&tios, B38400);
49
50 if (tcsetattr(fd, TCSAFLUSH, &tios) < 0) {
51 printk(UM_KERN_ERR "failed to set terminal attributes\n");
52 return -1;
53 }
54 return 0;
55 }
56
57 struct slip_pre_exec_data {
58 int stdin_fd;
59 int stdout_fd;
60 int close_me;
61 };
62
63 static void slip_pre_exec(void *arg)
64 {
65 struct slip_pre_exec_data *data = arg;
66
67 if (data->stdin_fd >= 0)
68 dup2(data->stdin_fd, 0);
69 dup2(data->stdout_fd, 1);
70 if (data->close_me >= 0)
71 close(data->close_me);
72 }
73
74 static int slip_tramp(char **argv, int fd)
75 {
76 struct slip_pre_exec_data pe_data;
77 char *output;
78 int pid, fds[2], err, output_len;
79
80 err = os_pipe(fds, 1, 0);
81 if (err < 0) {
82 printk(UM_KERN_ERR "slip_tramp : pipe failed, err = %d\n",
83 -err);
84 goto out;
85 }
86
87 err = 0;
88 pe_data.stdin_fd = fd;
89 pe_data.stdout_fd = fds[1];
90 pe_data.close_me = fds[0];
91 err = run_helper(slip_pre_exec, &pe_data, argv);
92 if (err < 0)
93 goto out_close;
94 pid = err;
95
96 output_len = UM_KERN_PAGE_SIZE;
97 output = uml_kmalloc(output_len, UM_GFP_KERNEL);
98 if (output == NULL) {
99 printk(UM_KERN_ERR "slip_tramp : failed to allocate output "
100 "buffer\n");
101 os_kill_process(pid, 1);
102 err = -ENOMEM;
103 goto out_close;
104 }
105
106 close(fds[1]);
107 read_output(fds[0], output, output_len);
108 printk("%s", output);
109
110 err = helper_wait(pid);
111 close(fds[0]);
112
113 kfree(output);
114 return err;
115
116 out_close:
117 close(fds[0]);
118 close(fds[1]);
119 out:
120 return err;
121 }
122
123 static int slip_open(void *data)
124 {
125 struct slip_data *pri = data;
126 char version_buf[sizeof("nnnnn\0")];
127 char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
128 char *argv[] = { "uml_net", version_buf, "slip", "up", gate_buf,
129 NULL };
130 int sfd, mfd, err;
131
132 err = get_pty();
133 if (err < 0) {
134 printk(UM_KERN_ERR "slip-open : Failed to open pty, err = %d\n",
135 -err);
136 goto out;
137 }
138 mfd = err;
139
140 err = open(ptsname(mfd), O_RDWR, 0);
141 if (err < 0) {
142 printk(UM_KERN_ERR "Couldn't open tty for slip line, "
143 "err = %d\n", -err);
144 goto out_close;
145 }
146 sfd = err;
147
148 err = set_up_tty(sfd);
149 if (err)
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(UM_KERN_ERR "slip_tramp failed - err = %d\n",
163 -err);
164 goto out_close2;
165 }
166 err = os_get_ifname(pri->slave, pri->name);
167 if (err < 0) {
168 printk(UM_KERN_ERR "get_ifname failed, err = %d\n",
169 -err);
170 goto out_close2;
171 }
172 iter_addresses(pri->dev, open_addr, pri->name);
173 }
174 else {
175 err = os_set_slip(sfd);
176 if (err < 0) {
177 printk(UM_KERN_ERR "Failed to set slip discipline "
178 "encapsulation - err = %d\n", -err);
179 goto out_close2;
180 }
181 }
182 return mfd;
183 out_close2:
184 close(sfd);
185 out_close:
186 close(mfd);
187 out:
188 return err;
189 }
190
191 static void slip_close(int fd, void *data)
192 {
193 struct slip_data *pri = data;
194 char version_buf[sizeof("nnnnn\0")];
195 char *argv[] = { "uml_net", version_buf, "slip", "down", pri->name,
196 NULL };
197 int err;
198
199 if (pri->gate_addr != NULL)
200 iter_addresses(pri->dev, close_addr, pri->name);
201
202 sprintf(version_buf, "%d", UML_NET_VERSION);
203
204 err = slip_tramp(argv, pri->slave);
205
206 if (err != 0)
207 printk(UM_KERN_ERR "slip_tramp failed - errno = %d\n", -err);
208 close(fd);
209 close(pri->slave);
210 pri->slave = -1;
211 }
212
213 int slip_user_read(int fd, void *buf, int len, struct slip_data *pri)
214 {
215 return slip_proto_read(fd, buf, len, &pri->slip);
216 }
217
218 int slip_user_write(int fd, void *buf, int len, struct slip_data *pri)
219 {
220 return slip_proto_write(fd, buf, len, &pri->slip);
221 }
222
223 static void slip_add_addr(unsigned char *addr, unsigned char *netmask,
224 void *data)
225 {
226 struct slip_data *pri = data;
227
228 if (pri->slave < 0)
229 return;
230 open_addr(addr, netmask, pri->name);
231 }
232
233 static void slip_del_addr(unsigned char *addr, unsigned char *netmask,
234 void *data)
235 {
236 struct slip_data *pri = data;
237
238 if (pri->slave < 0)
239 return;
240 close_addr(addr, netmask, pri->name);
241 }
242
243 const struct net_user_info slip_user_info = {
244 .init = slip_user_init,
245 .open = slip_open,
246 .close = slip_close,
247 .remove = NULL,
248 .add_address = slip_add_addr,
249 .delete_address = slip_del_addr,
250 .mtu = BUF_SIZE,
251 .max_packet = BUF_SIZE,
252 };
253
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