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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
5 * James Leu (jleu@mindspring.net).
6 * Copyright (C) 2001 by various other people who didn't put their name here.
7 */
8
9#include <stdio.h>
10#include <unistd.h>
11#include <errno.h>
12#include <string.h>
13#include <sys/socket.h>
14#include <sys/wait.h>
15#include "etap.h"
16#include <os.h>
17#include <net_user.h>
18#include <um_malloc.h>
19
20#define MAX_PACKET ETH_MAX_PACKET
21
22static int etap_user_init(void *data, void *dev)
23{
24 struct ethertap_data *pri = data;
25
26 pri->dev = dev;
27 return 0;
28}
29
30struct addr_change {
31 enum { ADD_ADDR, DEL_ADDR } what;
32 unsigned char addr[4];
33 unsigned char netmask[4];
34};
35
36static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
37 int fd)
38{
39 struct addr_change change;
40 char *output;
41 int n;
42
43 change.what = op;
44 memcpy(change.addr, addr, sizeof(change.addr));
45 memcpy(change.netmask, netmask, sizeof(change.netmask));
46 CATCH_EINTR(n = write(fd, &change, sizeof(change)));
47 if (n != sizeof(change)) {
48 printk(UM_KERN_ERR "etap_change - request failed, err = %d\n",
49 errno);
50 return;
51 }
52
53 output = uml_kmalloc(UM_KERN_PAGE_SIZE, UM_GFP_KERNEL);
54 if (output == NULL)
55 printk(UM_KERN_ERR "etap_change : Failed to allocate output "
56 "buffer\n");
57 read_output(fd, output, UM_KERN_PAGE_SIZE);
58 if (output != NULL) {
59 printk("%s", output);
60 kfree(output);
61 }
62}
63
64static void etap_open_addr(unsigned char *addr, unsigned char *netmask,
65 void *arg)
66{
67 etap_change(ADD_ADDR, addr, netmask, *((int *) arg));
68}
69
70static void etap_close_addr(unsigned char *addr, unsigned char *netmask,
71 void *arg)
72{
73 etap_change(DEL_ADDR, addr, netmask, *((int *) arg));
74}
75
76struct etap_pre_exec_data {
77 int control_remote;
78 int control_me;
79 int data_me;
80};
81
82static void etap_pre_exec(void *arg)
83{
84 struct etap_pre_exec_data *data = arg;
85
86 dup2(data->control_remote, 1);
87 close(data->data_me);
88 close(data->control_me);
89}
90
91static int etap_tramp(char *dev, char *gate, int control_me,
92 int control_remote, int data_me, int data_remote)
93{
94 struct etap_pre_exec_data pe_data;
95 int pid, err, n;
96 char version_buf[sizeof("nnnnn\0")];
97 char data_fd_buf[sizeof("nnnnnn\0")];
98 char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
99 char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
100 data_fd_buf, gate_buf, NULL };
101 char *nosetup_args[] = { "uml_net", version_buf, "ethertap",
102 dev, data_fd_buf, NULL };
103 char **args, c;
104
105 sprintf(data_fd_buf, "%d", data_remote);
106 sprintf(version_buf, "%d", UML_NET_VERSION);
107 if (gate != NULL) {
108 strscpy(gate_buf, gate);
109 args = setup_args;
110 }
111 else args = nosetup_args;
112
113 err = 0;
114 pe_data.control_remote = control_remote;
115 pe_data.control_me = control_me;
116 pe_data.data_me = data_me;
117 pid = run_helper(etap_pre_exec, &pe_data, args);
118
119 if (pid < 0)
120 err = pid;
121 close(data_remote);
122 close(control_remote);
123 CATCH_EINTR(n = read(control_me, &c, sizeof(c)));
124 if (n != sizeof(c)) {
125 err = -errno;
126 printk(UM_KERN_ERR "etap_tramp : read of status failed, "
127 "err = %d\n", -err);
128 return err;
129 }
130 if (c != 1) {
131 printk(UM_KERN_ERR "etap_tramp : uml_net failed\n");
132 err = helper_wait(pid);
133 }
134 return err;
135}
136
137static int etap_open(void *data)
138{
139 struct ethertap_data *pri = data;
140 char *output;
141 int data_fds[2], control_fds[2], err, output_len;
142
143 err = tap_open_common(pri->dev, pri->gate_addr);
144 if (err)
145 return err;
146
147 err = socketpair(AF_UNIX, SOCK_DGRAM, 0, data_fds);
148 if (err) {
149 err = -errno;
150 printk(UM_KERN_ERR "etap_open - data socketpair failed - "
151 "err = %d\n", errno);
152 return err;
153 }
154
155 err = socketpair(AF_UNIX, SOCK_STREAM, 0, control_fds);
156 if (err) {
157 err = -errno;
158 printk(UM_KERN_ERR "etap_open - control socketpair failed - "
159 "err = %d\n", errno);
160 goto out_close_data;
161 }
162
163 err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0],
164 control_fds[1], data_fds[0], data_fds[1]);
165 output_len = UM_KERN_PAGE_SIZE;
166 output = uml_kmalloc(output_len, UM_GFP_KERNEL);
167 read_output(control_fds[0], output, output_len);
168
169 if (output == NULL)
170 printk(UM_KERN_ERR "etap_open : failed to allocate output "
171 "buffer\n");
172 else {
173 printk("%s", output);
174 kfree(output);
175 }
176
177 if (err < 0) {
178 printk(UM_KERN_ERR "etap_tramp failed - err = %d\n", -err);
179 goto out_close_control;
180 }
181
182 pri->data_fd = data_fds[0];
183 pri->control_fd = control_fds[0];
184 iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
185 return data_fds[0];
186
187out_close_control:
188 close(control_fds[0]);
189 close(control_fds[1]);
190out_close_data:
191 close(data_fds[0]);
192 close(data_fds[1]);
193 return err;
194}
195
196static void etap_close(int fd, void *data)
197{
198 struct ethertap_data *pri = data;
199
200 iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
201 close(fd);
202
203 if (shutdown(pri->data_fd, SHUT_RDWR) < 0)
204 printk(UM_KERN_ERR "etap_close - shutdown data socket failed, "
205 "errno = %d\n", errno);
206
207 if (shutdown(pri->control_fd, SHUT_RDWR) < 0)
208 printk(UM_KERN_ERR "etap_close - shutdown control socket "
209 "failed, errno = %d\n", errno);
210
211 close(pri->data_fd);
212 pri->data_fd = -1;
213 close(pri->control_fd);
214 pri->control_fd = -1;
215}
216
217static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
218 void *data)
219{
220 struct ethertap_data *pri = data;
221
222 tap_check_ips(pri->gate_addr, addr);
223 if (pri->control_fd == -1)
224 return;
225 etap_open_addr(addr, netmask, &pri->control_fd);
226}
227
228static void etap_del_addr(unsigned char *addr, unsigned char *netmask,
229 void *data)
230{
231 struct ethertap_data *pri = data;
232
233 if (pri->control_fd == -1)
234 return;
235
236 etap_close_addr(addr, netmask, &pri->control_fd);
237}
238
239const struct net_user_info ethertap_user_info = {
240 .init = etap_user_init,
241 .open = etap_open,
242 .close = etap_close,
243 .remove = NULL,
244 .add_address = etap_add_addr,
245 .delete_address = etap_del_addr,
246 .mtu = ETH_MAX_PACKET,
247 .max_packet = ETH_MAX_PACKET + ETH_HEADER_ETHERTAP,
248};
1/*
2 * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and
4 * James Leu (jleu@mindspring.net).
5 * Copyright (C) 2001 by various other people who didn't put their name here.
6 * Licensed under the GPL.
7 */
8
9#include <stdio.h>
10#include <unistd.h>
11#include <errno.h>
12#include <string.h>
13#include <sys/socket.h>
14#include <sys/wait.h>
15#include "etap.h"
16#include "kern_constants.h"
17#include "os.h"
18#include "net_user.h"
19#include "um_malloc.h"
20#include "user.h"
21
22#define MAX_PACKET ETH_MAX_PACKET
23
24static int etap_user_init(void *data, void *dev)
25{
26 struct ethertap_data *pri = data;
27
28 pri->dev = dev;
29 return 0;
30}
31
32struct addr_change {
33 enum { ADD_ADDR, DEL_ADDR } what;
34 unsigned char addr[4];
35 unsigned char netmask[4];
36};
37
38static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
39 int fd)
40{
41 struct addr_change change;
42 char *output;
43 int n;
44
45 change.what = op;
46 memcpy(change.addr, addr, sizeof(change.addr));
47 memcpy(change.netmask, netmask, sizeof(change.netmask));
48 CATCH_EINTR(n = write(fd, &change, sizeof(change)));
49 if (n != sizeof(change)) {
50 printk(UM_KERN_ERR "etap_change - request failed, err = %d\n",
51 errno);
52 return;
53 }
54
55 output = uml_kmalloc(UM_KERN_PAGE_SIZE, UM_GFP_KERNEL);
56 if (output == NULL)
57 printk(UM_KERN_ERR "etap_change : Failed to allocate output "
58 "buffer\n");
59 read_output(fd, output, UM_KERN_PAGE_SIZE);
60 if (output != NULL) {
61 printk("%s", output);
62 kfree(output);
63 }
64}
65
66static void etap_open_addr(unsigned char *addr, unsigned char *netmask,
67 void *arg)
68{
69 etap_change(ADD_ADDR, addr, netmask, *((int *) arg));
70}
71
72static void etap_close_addr(unsigned char *addr, unsigned char *netmask,
73 void *arg)
74{
75 etap_change(DEL_ADDR, addr, netmask, *((int *) arg));
76}
77
78struct etap_pre_exec_data {
79 int control_remote;
80 int control_me;
81 int data_me;
82};
83
84static void etap_pre_exec(void *arg)
85{
86 struct etap_pre_exec_data *data = arg;
87
88 dup2(data->control_remote, 1);
89 close(data->data_me);
90 close(data->control_me);
91}
92
93static int etap_tramp(char *dev, char *gate, int control_me,
94 int control_remote, int data_me, int data_remote)
95{
96 struct etap_pre_exec_data pe_data;
97 int pid, err, n;
98 char version_buf[sizeof("nnnnn\0")];
99 char data_fd_buf[sizeof("nnnnnn\0")];
100 char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
101 char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
102 data_fd_buf, gate_buf, NULL };
103 char *nosetup_args[] = { "uml_net", version_buf, "ethertap",
104 dev, data_fd_buf, NULL };
105 char **args, c;
106
107 sprintf(data_fd_buf, "%d", data_remote);
108 sprintf(version_buf, "%d", UML_NET_VERSION);
109 if (gate != NULL) {
110 strcpy(gate_buf, gate);
111 args = setup_args;
112 }
113 else args = nosetup_args;
114
115 err = 0;
116 pe_data.control_remote = control_remote;
117 pe_data.control_me = control_me;
118 pe_data.data_me = data_me;
119 pid = run_helper(etap_pre_exec, &pe_data, args);
120
121 if (pid < 0)
122 err = pid;
123 close(data_remote);
124 close(control_remote);
125 CATCH_EINTR(n = read(control_me, &c, sizeof(c)));
126 if (n != sizeof(c)) {
127 err = -errno;
128 printk(UM_KERN_ERR "etap_tramp : read of status failed, "
129 "err = %d\n", -err);
130 return err;
131 }
132 if (c != 1) {
133 printk(UM_KERN_ERR "etap_tramp : uml_net failed\n");
134 err = helper_wait(pid);
135 }
136 return err;
137}
138
139static int etap_open(void *data)
140{
141 struct ethertap_data *pri = data;
142 char *output;
143 int data_fds[2], control_fds[2], err, output_len;
144
145 err = tap_open_common(pri->dev, pri->gate_addr);
146 if (err)
147 return err;
148
149 err = socketpair(AF_UNIX, SOCK_DGRAM, 0, data_fds);
150 if (err) {
151 err = -errno;
152 printk(UM_KERN_ERR "etap_open - data socketpair failed - "
153 "err = %d\n", errno);
154 return err;
155 }
156
157 err = socketpair(AF_UNIX, SOCK_STREAM, 0, control_fds);
158 if (err) {
159 err = -errno;
160 printk(UM_KERN_ERR "etap_open - control socketpair failed - "
161 "err = %d\n", errno);
162 goto out_close_data;
163 }
164
165 err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0],
166 control_fds[1], data_fds[0], data_fds[1]);
167 output_len = UM_KERN_PAGE_SIZE;
168 output = uml_kmalloc(output_len, UM_GFP_KERNEL);
169 read_output(control_fds[0], output, output_len);
170
171 if (output == NULL)
172 printk(UM_KERN_ERR "etap_open : failed to allocate output "
173 "buffer\n");
174 else {
175 printk("%s", output);
176 kfree(output);
177 }
178
179 if (err < 0) {
180 printk(UM_KERN_ERR "etap_tramp failed - err = %d\n", -err);
181 goto out_close_control;
182 }
183
184 pri->data_fd = data_fds[0];
185 pri->control_fd = control_fds[0];
186 iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
187 return data_fds[0];
188
189out_close_control:
190 close(control_fds[0]);
191 close(control_fds[1]);
192out_close_data:
193 close(data_fds[0]);
194 close(data_fds[1]);
195 return err;
196}
197
198static void etap_close(int fd, void *data)
199{
200 struct ethertap_data *pri = data;
201
202 iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
203 close(fd);
204
205 if (shutdown(pri->data_fd, SHUT_RDWR) < 0)
206 printk(UM_KERN_ERR "etap_close - shutdown data socket failed, "
207 "errno = %d\n", errno);
208
209 if (shutdown(pri->control_fd, SHUT_RDWR) < 0)
210 printk(UM_KERN_ERR "etap_close - shutdown control socket "
211 "failed, errno = %d\n", errno);
212
213 close(pri->data_fd);
214 pri->data_fd = -1;
215 close(pri->control_fd);
216 pri->control_fd = -1;
217}
218
219static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
220 void *data)
221{
222 struct ethertap_data *pri = data;
223
224 tap_check_ips(pri->gate_addr, addr);
225 if (pri->control_fd == -1)
226 return;
227 etap_open_addr(addr, netmask, &pri->control_fd);
228}
229
230static void etap_del_addr(unsigned char *addr, unsigned char *netmask,
231 void *data)
232{
233 struct ethertap_data *pri = data;
234
235 if (pri->control_fd == -1)
236 return;
237
238 etap_close_addr(addr, netmask, &pri->control_fd);
239}
240
241const struct net_user_info ethertap_user_info = {
242 .init = etap_user_init,
243 .open = etap_open,
244 .close = etap_close,
245 .remove = NULL,
246 .add_address = etap_add_addr,
247 .delete_address = etap_del_addr,
248 .mtu = ETH_MAX_PACKET,
249 .max_packet = ETH_MAX_PACKET + ETH_HEADER_ETHERTAP,
250};