Merge ../linux-2.6
[linux-2.6] / arch / um / os-Linux / drivers / tuntap_user.c
1 /* 
2  * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  */
5
6 #include <stdio.h>
7 #include <stddef.h>
8 #include <stdlib.h>
9 #include <unistd.h>
10 #include <errno.h>
11 #include <sys/wait.h>
12 #include <sys/socket.h>
13 #include <sys/un.h>
14 #include <sys/uio.h>
15 #include <sys/ioctl.h>
16 #include <net/if.h>
17 #include <linux/if_tun.h>
18 #include "net_user.h"
19 #include "tuntap.h"
20 #include "kern_util.h"
21 #include "user_util.h"
22 #include "user.h"
23 #include "os.h"
24
25 #define MAX_PACKET ETH_MAX_PACKET
26
27 void tuntap_user_init(void *data, void *dev)
28 {
29         struct tuntap_data *pri = data;
30
31         pri->dev = dev;
32 }
33
34 static void tuntap_add_addr(unsigned char *addr, unsigned char *netmask,
35                             void *data)
36 {
37         struct tuntap_data *pri = data;
38
39         tap_check_ips(pri->gate_addr, addr);
40         if((pri->fd == -1) || pri->fixed_config) return;
41         open_addr(addr, netmask, pri->dev_name);
42 }
43
44 static void tuntap_del_addr(unsigned char *addr, unsigned char *netmask,
45                             void *data)
46 {
47         struct tuntap_data *pri = data;
48
49         if((pri->fd == -1) || pri->fixed_config) return;
50         close_addr(addr, netmask, pri->dev_name);
51 }
52
53 struct tuntap_pre_exec_data {
54         int stdout;
55         int close_me;
56 };
57
58 static void tuntap_pre_exec(void *arg)
59 {
60         struct tuntap_pre_exec_data *data = arg;
61         
62         dup2(data->stdout, 1);
63         os_close_file(data->close_me);
64 }
65
66 static int tuntap_open_tramp(char *gate, int *fd_out, int me, int remote,
67                              char *buffer, int buffer_len, int *used_out)
68 {
69         struct tuntap_pre_exec_data data;
70         char version_buf[sizeof("nnnnn\0")];
71         char *argv[] = { "uml_net", version_buf, "tuntap", "up", gate,
72                          NULL };
73         char buf[CMSG_SPACE(sizeof(*fd_out))];
74         struct msghdr msg;
75         struct cmsghdr *cmsg;
76         struct iovec iov;
77         int pid, n, err;
78
79         sprintf(version_buf, "%d", UML_NET_VERSION);
80
81         data.stdout = remote;
82         data.close_me = me;
83
84         pid = run_helper(tuntap_pre_exec, &data, argv, NULL);
85
86         if(pid < 0) return(-pid);
87
88         os_close_file(remote);
89
90         msg.msg_name = NULL;
91         msg.msg_namelen = 0;
92         if(buffer != NULL){
93                 iov = ((struct iovec) { buffer, buffer_len });
94                 msg.msg_iov = &iov;
95                 msg.msg_iovlen = 1;
96         }
97         else {
98                 msg.msg_iov = NULL;
99                 msg.msg_iovlen = 0;
100         }
101         msg.msg_control = buf;
102         msg.msg_controllen = sizeof(buf);
103         msg.msg_flags = 0;
104         n = recvmsg(me, &msg, 0);
105         *used_out = n;
106         if(n < 0){
107                 err = -errno;
108                 printk("tuntap_open_tramp : recvmsg failed - errno = %d\n", 
109                        errno);
110                 return err;
111         }
112         CATCH_EINTR(waitpid(pid, NULL, 0));
113
114         cmsg = CMSG_FIRSTHDR(&msg);
115         if(cmsg == NULL){
116                 printk("tuntap_open_tramp : didn't receive a message\n");
117                 return(-EINVAL);
118         }
119         if((cmsg->cmsg_level != SOL_SOCKET) || 
120            (cmsg->cmsg_type != SCM_RIGHTS)){
121                 printk("tuntap_open_tramp : didn't receive a descriptor\n");
122                 return(-EINVAL);
123         }
124         *fd_out = ((int *) CMSG_DATA(cmsg))[0];
125         return(0);
126 }
127
128 static int tuntap_open(void *data)
129 {
130         struct ifreq ifr;
131         struct tuntap_data *pri = data;
132         char *output, *buffer;
133         int err, fds[2], len, used;
134
135         err = tap_open_common(pri->dev, pri->gate_addr);
136         if(err < 0)
137                 return(err);
138
139         if(pri->fixed_config){
140                 pri->fd = os_open_file("/dev/net/tun", of_rdwr(OPENFLAGS()), 0);
141                 if(pri->fd < 0){
142                         printk("Failed to open /dev/net/tun, err = %d\n",
143                                -pri->fd);
144                         return(pri->fd);
145                 }
146                 memset(&ifr, 0, sizeof(ifr));
147                 ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
148                 strlcpy(ifr.ifr_name, pri->dev_name, sizeof(ifr.ifr_name));
149                 if(ioctl(pri->fd, TUNSETIFF, (void *) &ifr) < 0){
150                         err = -errno;
151                         printk("TUNSETIFF failed, errno = %d\n", errno);
152                         os_close_file(pri->fd);
153                         return err;
154                 }
155         }
156         else {
157                 err = os_pipe(fds, 0, 0);
158                 if(err < 0){
159                         printk("tuntap_open : os_pipe failed - err = %d\n",
160                                -err);
161                         return(err);
162                 }
163
164                 buffer = get_output_buffer(&len);
165                 if(buffer != NULL) len--;
166                 used = 0;
167
168                 err = tuntap_open_tramp(pri->gate_addr, &pri->fd, fds[0],
169                                         fds[1], buffer, len, &used);
170
171                 output = buffer;
172                 if(err < 0) {
173                         printk("%s", output);
174                         free_output_buffer(buffer);
175                         printk("tuntap_open_tramp failed - err = %d\n", -err);
176                         return(err);
177                 }
178
179                 pri->dev_name = uml_strdup(buffer);
180                 output += IFNAMSIZ;
181                 printk("%s", output);
182                 free_output_buffer(buffer);
183
184                 os_close_file(fds[0]);
185                 iter_addresses(pri->dev, open_addr, pri->dev_name);
186         }
187
188         return(pri->fd);
189 }
190
191 static void tuntap_close(int fd, void *data)
192 {
193         struct tuntap_data *pri = data;
194
195         if(!pri->fixed_config) 
196                 iter_addresses(pri->dev, close_addr, pri->dev_name);
197         os_close_file(fd);
198         pri->fd = -1;
199 }
200
201 static int tuntap_set_mtu(int mtu, void *data)
202 {
203         return(mtu);
204 }
205
206 struct net_user_info tuntap_user_info = {
207         .init           = tuntap_user_init,
208         .open           = tuntap_open,
209         .close          = tuntap_close,
210         .remove         = NULL,
211         .set_mtu        = tuntap_set_mtu,
212         .add_address    = tuntap_add_addr,
213         .delete_address = tuntap_del_addr,
214         .max_packet     = MAX_PACKET
215 };
216
217 /*
218  * Overrides for Emacs so that we follow Linus's tabbing style.
219  * Emacs will notice this stuff at the end of the file and automatically
220  * adjust the settings for this buffer only.  This must remain at the end
221  * of the file.
222  * ---------------------------------------------------------------------------
223  * Local variables:
224  * c-file-style: "linux"
225  * End:
226  */