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 "helper.h"
  23 #include "os.h"
  24
  25 #define MAX_PACKET ETH_MAX_PACKET
  26
  27 void etap_user_init(void *data, void *dev)
  28 {
  29         struct ethertap_data *pri = data;
  30
  31         pri->dev = dev;
  32 }
  33
  34 struct addr_change {
  35         enum { ADD_ADDR, DEL_ADDR } what;
  36         unsigned char addr[4];
  37         unsigned char netmask[4];
  38 };
  39
  40 static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
  41                         int fd)
  42 {
  43         struct addr_change change;
  44         void *output;
  45         int n;
  46
  47         change.what = op;
  48         memcpy(change.addr, addr, sizeof(change.addr));
  49         memcpy(change.netmask, netmask, sizeof(change.netmask));
  50         n = os_write_file(fd, &change, sizeof(change));
  51         if(n != sizeof(change))
  52                 printk("etap_change - request failed, err = %d\n", -n);
  53         output = um_kmalloc(page_size());
  54         if(output == NULL)
  55                 printk("etap_change : Failed to allocate output buffer\n");
  56         read_output(fd, output, page_size());
  57         if(output != NULL){
  58                 printk("%s", output);
  59                 kfree(output);
  60         }
  61 }
  62
  63 static void etap_open_addr(unsigned char *addr, unsigned char *netmask,
  64                            void *arg)
  65 {
  66         etap_change(ADD_ADDR, addr, netmask, *((int *) arg));
  67 }
  68
  69 static void etap_close_addr(unsigned char *addr, unsigned char *netmask,
  70                             void *arg)
  71 {
  72         etap_change(DEL_ADDR, addr, netmask, *((int *) arg));
  73 }
  74
  75 struct etap_pre_exec_data {
  76         int control_remote;
  77         int control_me;
  78         int data_me;
  79 };
  80
  81 static void etap_pre_exec(void *arg)
  82 {
  83         struct etap_pre_exec_data *data = arg;
  84
  85         dup2(data->control_remote, 1);
  86         os_close_file(data->data_me);
  87         os_close_file(data->control_me);
  88 }
  89
  90 static int etap_tramp(char *dev, char *gate, int control_me,
  91                       int control_remote, int data_me, int data_remote)
  92 {
  93         struct etap_pre_exec_data pe_data;
  94         int pid, status, err, n;
  95         char version_buf[sizeof("nnnnn\0")];
  96         char data_fd_buf[sizeof("nnnnnn\0")];
  97         char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
  98         char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
  99                                data_fd_buf, gate_buf, NULL };
 100         char *nosetup_args[] = { "uml_net", version_buf, "ethertap",
 101                                  dev, data_fd_buf, NULL };
 102         char **args, c;
 103
 104         sprintf(data_fd_buf, "%d", data_remote);
 105         sprintf(version_buf, "%d", UML_NET_VERSION);
 106         if(gate != NULL){
 107                 strcpy(gate_buf, gate);
 108                 args = setup_args;
 109         }
 110         else args = nosetup_args;
 111
 112         err = 0;
 113         pe_data.control_remote = control_remote;
 114         pe_data.control_me = control_me;
 115         pe_data.data_me = data_me;
 116         pid = run_helper(etap_pre_exec, &pe_data, args, NULL);
 117
 118         if(pid < 0) err = pid;
 119         os_close_file(data_remote);
 120         os_close_file(control_remote);
 121         n = os_read_file(control_me, &c, sizeof(c));
 122         if(n != sizeof(c)){
 123                 printk("etap_tramp : read of status failed, err = %d\n", -n);
 124                 return(-EINVAL);
 125         }
 126         if(c != 1){
 127                 printk("etap_tramp : uml_net failed\n");
 128                 err = -EINVAL;
 129                 CATCH_EINTR(n = waitpid(pid, &status, 0));
 130                 if(n < 0)
 131                         err = -errno;
 132                 else if(!WIFEXITED(status) || (WEXITSTATUS(status) != 1))
 133                         printk("uml_net didn't exit with status 1\n");
 134         }
 135         return(err);
 136 }
 137
 138 static int etap_open(void *data)
 139 {
 140         struct ethertap_data *pri = data;
 141         char *output;
 142         int data_fds[2], control_fds[2], err, output_len;
 143
 144         err = tap_open_common(pri->dev, pri->gate_addr);
 145         if(err) return(err);
 146
 147         err = os_pipe(data_fds, 0, 0);
 148         if(err < 0){
 149                 printk("data os_pipe failed - err = %d\n", -err);
 150                 return(err);
 151         }
 152
 153         err = os_pipe(control_fds, 1, 0);
 154         if(err < 0){
 155                 printk("control os_pipe failed - err = %d\n", -err);
 156                 return(err);
 157         }
 158
 159         err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0],
 160                          control_fds[1], data_fds[0], data_fds[1]);
 161         output_len = page_size();
 162         output = um_kmalloc(output_len);
 163         read_output(control_fds[0], output, output_len);
 164
 165         if(output == NULL)
 166                 printk("etap_open : failed to allocate output buffer\n");
 167         else {
 168                 printk("%s", output);
 169                 kfree(output);
 170         }
 171
 172         if(err < 0){
 173                 printk("etap_tramp failed - err = %d\n", -err);
 174                 return(err);
 175         }
 176
 177         pri->data_fd = data_fds[0];
 178         pri->control_fd = control_fds[0];
 179         iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
 180         return(data_fds[0]);
 181 }
 182
 183 static void etap_close(int fd, void *data)
 184 {
 185         struct ethertap_data *pri = data;
 186
 187         iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
 188         os_close_file(fd);
 189         os_shutdown_socket(pri->data_fd, 1, 1);
 190         os_close_file(pri->data_fd);
 191         pri->data_fd = -1;
 192         os_close_file(pri->control_fd);
 193         pri->control_fd = -1;
 194 }
 195
 196 static int etap_set_mtu(int mtu, void *data)
 197 {
 198         return(mtu);
 199 }
 200
 201 static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
 202                           void *data)
 203 {
 204         struct ethertap_data *pri = data;
 205
 206         tap_check_ips(pri->gate_addr, addr);
 207         if(pri->control_fd == -1) return;
 208         etap_open_addr(addr, netmask, &pri->control_fd);
 209 }
 210
 211 static void etap_del_addr(unsigned char *addr, unsigned char *netmask,
 212                           void *data)
 213 {
 214         struct ethertap_data *pri = data;
 215
 216         if(pri->control_fd == -1) return;
 217         etap_close_addr(addr, netmask, &pri->control_fd);
 218 }
 219
 220 struct net_user_info ethertap_user_info = {
 221         .init           = etap_user_init,
 222         .open           = etap_open,
 223         .close          = etap_close,
 224         .remove         = NULL,
 225         .set_mtu        = etap_set_mtu,
 226         .add_address    = etap_add_addr,
 227         .delete_address = etap_del_addr,
 228         .max_packet     = MAX_PACKET - ETH_HEADER_ETHERTAP
 229 };
 230
 231 /*
 232  * Overrides for Emacs so that we follow Linus's tabbing style.
 233  * Emacs will notice this stuff at the end of the file and automatically
 234  * adjust the settings for this buffer only.  This must remain at the end
 235  * of the file.
 236  * ---------------------------------------------------------------------------
 237  * Local variables:
 238  * c-file-style: "linux"
 239  * End:
 240  */