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
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
|
/*
* Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <stdio.h>
#include <unistd.h>
#include <stdarg.h>
#include <errno.h>
#include <stddef.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include "net_user.h"
#include "os.h"
#include "um_malloc.h"
int tap_open_common(void *dev, char *gate_addr)
{
int tap_addr[4];
if (gate_addr == NULL)
return 0;
if (sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0],
&tap_addr[1], &tap_addr[2], &tap_addr[3]) != 4) {
printk(UM_KERN_ERR "Invalid tap IP address - '%s'\n",
gate_addr);
return -EINVAL;
}
return 0;
}
void tap_check_ips(char *gate_addr, unsigned char *eth_addr)
{
int tap_addr[4];
if ((gate_addr != NULL) &&
(sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0],
&tap_addr[1], &tap_addr[2], &tap_addr[3]) == 4) &&
(eth_addr[0] == tap_addr[0]) &&
(eth_addr[1] == tap_addr[1]) &&
(eth_addr[2] == tap_addr[2]) &&
(eth_addr[3] == tap_addr[3])) {
printk(UM_KERN_ERR "The tap IP address and the UML eth IP "
"address must be different\n");
}
}
/* Do reliable error handling as this fails frequently enough. */
void read_output(int fd, char *output, int len)
{
int remain, ret, expected;
char c;
char *str;
if (output == NULL) {
output = &c;
len = sizeof(c);
}
*output = '\0';
ret = read(fd, &remain, sizeof(remain));
if (ret != sizeof(remain)) {
if (ret < 0)
ret = -errno;
expected = sizeof(remain);
str = "length";
goto err;
}
while (remain != 0) {
expected = (remain < len) ? remain : len;
ret = read(fd, output, expected);
if (ret != expected) {
if (ret < 0)
ret = -errno;
str = "data";
goto err;
}
remain -= ret;
}
return;
err:
if (ret < 0)
printk(UM_KERN_ERR "read_output - read of %s failed, "
"errno = %d\n", str, -ret);
else
printk(UM_KERN_ERR "read_output - read of %s failed, read only "
"%d of %d bytes\n", str, ret, expected);
}
int net_read(int fd, void *buf, int len)
{
int n;
n = read(fd, buf, len);
if ((n < 0) && (errno == EAGAIN))
return 0;
else if (n == 0)
return -ENOTCONN;
return n;
}
int net_recvfrom(int fd, void *buf, int len)
{
int n;
CATCH_EINTR(n = recvfrom(fd, buf, len, 0, NULL, NULL));
if (n < 0) {
if (errno == EAGAIN)
return 0;
return -errno;
}
else if (n == 0)
return -ENOTCONN;
return n;
}
int net_write(int fd, void *buf, int len)
{
int n;
n = write(fd, buf, len);
if ((n < 0) && (errno == EAGAIN))
return 0;
else if (n == 0)
return -ENOTCONN;
return n;
}
int net_send(int fd, void *buf, int len)
{
int n;
CATCH_EINTR(n = send(fd, buf, len, 0));
if (n < 0) {
if (errno == EAGAIN)
return 0;
return -errno;
}
else if (n == 0)
return -ENOTCONN;
return n;
}
int net_sendto(int fd, void *buf, int len, void *to, int sock_len)
{
int n;
CATCH_EINTR(n = sendto(fd, buf, len, 0, (struct sockaddr *) to,
sock_len));
if (n < 0) {
if (errno == EAGAIN)
return 0;
return -errno;
}
else if (n == 0)
return -ENOTCONN;
return n;
}
struct change_pre_exec_data {
int close_me;
int stdout;
};
static void change_pre_exec(void *arg)
{
struct change_pre_exec_data *data = arg;
close(data->close_me);
dup2(data->stdout, 1);
}
static int change_tramp(char **argv, char *output, int output_len)
{
int pid, fds[2], err;
struct change_pre_exec_data pe_data;
err = os_pipe(fds, 1, 0);
if (err < 0) {
printk(UM_KERN_ERR "change_tramp - pipe failed, err = %d\n",
-err);
return err;
}
pe_data.close_me = fds[0];
pe_data.stdout = fds[1];
pid = run_helper(change_pre_exec, &pe_data, argv);
if (pid > 0) /* Avoid hang as we won't get data in failure case. */
read_output(fds[0], output, output_len);
close(fds[0]);
close(fds[1]);
if (pid > 0)
helper_wait(pid);
return pid;
}
static void change(char *dev, char *what, unsigned char *addr,
unsigned char *netmask)
{
char addr_buf[sizeof("255.255.255.255\0")];
char netmask_buf[sizeof("255.255.255.255\0")];
char version[sizeof("nnnnn\0")];
char *argv[] = { "uml_net", version, what, dev, addr_buf,
netmask_buf, NULL };
char *output;
int output_len, pid;
sprintf(version, "%d", UML_NET_VERSION);
sprintf(addr_buf, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
sprintf(netmask_buf, "%d.%d.%d.%d", netmask[0], netmask[1],
netmask[2], netmask[3]);
output_len = UM_KERN_PAGE_SIZE;
output = uml_kmalloc(output_len, UM_GFP_KERNEL);
if (output == NULL)
printk(UM_KERN_ERR "change : failed to allocate output "
"buffer\n");
pid = change_tramp(argv, output, output_len);
if (pid < 0) {
kfree(output);
return;
}
if (output != NULL) {
printk("%s", output);
kfree(output);
}
}
void open_addr(unsigned char *addr, unsigned char *netmask, void *arg)
{
change(arg, "add", addr, netmask);
}
void close_addr(unsigned char *addr, unsigned char *netmask, void *arg)
{
change(arg, "del", addr, netmask);
}
char *split_if_spec(char *str, ...)
{
char **arg, *end;
va_list ap;
va_start(ap, str);
while ((arg = va_arg(ap, char **)) != NULL) {
if (*str == '\0')
return NULL;
end = strchr(str, ',');
if (end != str)
*arg = str;
if (end == NULL)
return NULL;
*end++ = '\0';
str = end;
}
va_end(ap);
return str;
}
|
