summaryrefslogtreecommitdiffstats
path: root/arch/um/drivers/net_user.c
blob: 098fa65981aba6404eb9422137466d39d5ffc38b (plain)
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
/* 
 * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
 * Licensed under the GPL
 */

#include <stddef.h>
#include <stdarg.h>
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include "user.h"
#include "user_util.h"
#include "kern_util.h"
#include "net_user.h"
#include "os.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("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("The tap IP address and the UML eth IP address"
		       " must be different\n");
	}
}

void read_output(int fd, char *output, int len)
{
	int remain, n, actual;
	char c;

	if(output == NULL){
		output = &c;
		len = sizeof(c);
	}
		
	*output = '\0';
	n = os_read_file(fd, &remain, sizeof(remain));
	if(n != sizeof(remain)){
		printk("read_output - read of length failed, err = %d\n", -n);
		return;
	}

	while(remain != 0){
		n = (remain < len) ? remain : len;
		actual = os_read_file(fd, output, n);
		if(actual != n){
			printk("read_output - read of data failed, "
			       "err = %d\n", -actual);
			return;
		}
		remain -= actual;
	}
	return;
}

int net_read(int fd, void *buf, int len)
{
	int n;

	n = os_read_file(fd,  buf,  len);

	if(n == -EAGAIN)
		return(0);
	else if(n == 0)
		return(-ENOTCONN);
	return(n);
}

int net_recvfrom(int fd, void *buf, int len)
{
	int n;

	while(((n = recvfrom(fd,  buf,  len, 0, NULL, NULL)) < 0) && 
	      (errno == EINTR)) ;

	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 = os_write_file(fd, buf, len);

	if(n == -EAGAIN)
		return(0);
	else if(n == 0)
		return(-ENOTCONN);
	return(n);
}

int net_send(int fd, void *buf, int len)
{
	int n;

	while(((n = send(fd, buf, len, 0)) < 0) && (errno == EINTR)) ;
	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;

	while(((n = sendto(fd, buf, len, 0, (struct sockaddr *) to,
			   sock_len)) < 0) && (errno == EINTR)) ;
	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;

	os_close_file(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("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, NULL);

	read_output(fds[0], output, output_len);
	os_close_file(fds[0]);
	os_close_file(fds[1]);

	if (pid > 0)
		CATCH_EINTR(err = waitpid(pid, NULL, 0));
	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 = page_size();
	output = um_kmalloc(output_len);
	if(output == NULL)
		printk("change : failed to allocate output buffer\n");

	pid = change_tramp(argv, output, output_len);
	if(pid < 0) 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);
}

/*
 * Overrides for Emacs so that we follow Linus's tabbing style.
 * Emacs will notice this stuff at the end of the file and automatically
 * adjust the settings for this buffer only.  This must remain at the end
 * of the file.
 * ---------------------------------------------------------------------------
 * Local variables:
 * c-file-style: "linux"
 * End:
 */
OpenPOWER on IntegriCloud