Rev Author Line No. Line
3328 povik 1 /*
2 * Copyright (c) 2001, Swedish Institute of Computer Science.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * 3. Neither the name of the Institute nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * Author: Adam Dunkels <adam@sics.se>
33 *
34 * $Id: tapdev.c,v 1.7.2.1 2003/10/07 13:23:19 adam Exp $
35 */
36  
37  
38 #include <fcntl.h>
39 #include <stdlib.h>
40 #include <stdio.h>
41 #include <unistd.h>
42 #include <string.h>
43 #include <sys/ioctl.h>
44 #include <sys/socket.h>
45 #include <sys/types.h>
46 #include <sys/time.h>
47 #include <sys/uio.h>
48 #include <sys/socket.h>
49  
50 #ifdef linux
51 #include <sys/ioctl.h>
52 #include <linux/if.h>
53 #include <linux/if_tun.h>
54 #define DEVTAP "/dev/net/tun"
55 #else /* linux */
56 #define DEVTAP "/dev/tap0"
57 #endif /* linux */
58  
59 #include "uip.h"
60  
61 static int fd;
62  
63 static unsigned long lasttime;
64 static struct timezone tz;
65  
66 /*-----------------------------------------------------------------------------------*/
67 void
68 tapdev_init(void)
69 {
70 char buf[1024];
71  
72 fd = open(DEVTAP, O_RDWR);
73 if(fd == -1) {
74 perror("tapdev: tapdev_init: open");
75 exit(1);
76 }
77  
78 #ifdef linux
79 {
80 struct ifreq ifr;
81 memset(&ifr, 0, sizeof(ifr));
82 ifr.ifr_flags = IFF_TAP|IFF_NO_PI;
83 if (ioctl(fd, TUNSETIFF, (void *) &ifr) < 0) {
84 perror(buf);
85 exit(1);
86 }
87 }
88 #endif /* Linux */
89  
90 snprintf(buf, sizeof(buf), "ifconfig tap0 inet %d.%d.%d.%d",
91 UIP_DRIPADDR0, UIP_DRIPADDR1, UIP_DRIPADDR2, UIP_DRIPADDR3);
92 system(buf);
93  
94 lasttime = 0;
95 }
96 /*-----------------------------------------------------------------------------------*/
97 unsigned int
98 tapdev_read(void)
99 {
100 fd_set fdset;
101 struct timeval tv, now;
102 int ret;
103  
104 if(lasttime >= 500000) {
105 lasttime = 0;
106 return 0;
107 }
108  
109 tv.tv_sec = 0;
110 tv.tv_usec = 500000 - lasttime;
111  
112  
113 FD_ZERO(&fdset);
114 FD_SET(fd, &fdset);
115  
116 gettimeofday(&now, &tz);
117 ret = select(fd + 1, &fdset, NULL, NULL, &tv);
118 if(ret == 0) {
119 lasttime = 0;
120 return 0;
121 }
122 ret = read(fd, uip_buf, UIP_BUFSIZE);
123 if(ret == -1) {
124 perror("tap_dev: tapdev_read: read");
125 }
126 gettimeofday(&tv, &tz);
127 lasttime += (tv.tv_sec - now.tv_sec) * 1000000 + (tv.tv_usec - now.tv_usec);
128  
129 return ret;
130 }
131 /*-----------------------------------------------------------------------------------*/
132 void
133 tapdev_send(void)
134 {
135 int ret;
136 struct iovec iov[2];
137  
138 #ifdef linux
139 {
140 char tmpbuf[UIP_BUFSIZE];
141 int i;
142  
143 for(i = 0; i < 40 + UIP_LLH_LEN; i++) {
144 tmpbuf[i] = uip_buf[i];
145 }
146  
147 for(; i < uip_len; i++) {
148 tmpbuf[i] = uip_appdata[i - 40 - UIP_LLH_LEN];
149 }
150  
151 ret = write(fd, tmpbuf, uip_len);
152 }
153 #else
154  
155 if(uip_len < 40 + UIP_LLH_LEN) {
156 ret = write(fd, uip_buf, uip_len + UIP_LLH_LEN);
157 } else {
158 iov[0].iov_base = uip_buf;
159 iov[0].iov_len = 40 + UIP_LLH_LEN;
160 iov[1].iov_base = (char *)uip_appdata;
161 iov[1].iov_len = uip_len - (40 + UIP_LLH_LEN);
162  
163 ret = writev(fd, iov, 2);
164 }
165 #endif
166 if(ret == -1) {
167 perror("tap_dev: tapdev_send: writev");
168 exit(1);
169 }
170 }
171 /*-----------------------------------------------------------------------------------*/