arch/um/os-Linux/drivers/ethertap_user.c

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