arch/um/drivers/slip_user.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <unistd.h>
   4 #include <stddef.h>
   5 #include <sched.h>
   6 #include <string.h>
   7 #include <errno.h>
   8 #include <sys/termios.h>
   9 #include <sys/wait.h>
  10 #include <sys/signal.h>
  11 #include "kern_util.h"
  12 #include "user.h"
  13 #include "net_user.h"
  14 #include "slip.h"
  15 #include "slip_common.h"
  16 #include "os.h"
  17 #include "um_malloc.h"
  18 #include "kern_constants.h"
  19
  20 static int slip_user_init(void *data, void *dev)
  21 {
  22         struct slip_data *pri = data;
  23
  24         pri->dev = dev;
  25         return 0;
  26 }
  27
  28 static int set_up_tty(int fd)
  29 {
  30         int i;
  31         struct termios tios;
  32
  33         if (tcgetattr(fd, &tios) < 0) {
  34                 printk("could not get initial terminal attributes\n");
  35                 return(-1);
  36         }
  37
  38         tios.c_cflag = CS8 | CREAD | HUPCL | CLOCAL;
  39         tios.c_iflag = IGNBRK | IGNPAR;
  40         tios.c_oflag = 0;
  41         tios.c_lflag = 0;
  42         for (i = 0; i < NCCS; i++)
  43                 tios.c_cc[i] = 0;
  44         tios.c_cc[VMIN] = 1;
  45         tios.c_cc[VTIME] = 0;
  46
  47         cfsetospeed(&tios, B38400);
  48         cfsetispeed(&tios, B38400);
  49
  50         if (tcsetattr(fd, TCSAFLUSH, &tios) < 0) {
  51                 printk("failed to set terminal attributes\n");
  52                 return(-1);
  53         }
  54         return(0);
  55 }
  56
  57 struct slip_pre_exec_data {
  58         int stdin;
  59         int stdout;
  60         int close_me;
  61 };
  62
  63 static void slip_pre_exec(void *arg)
  64 {
  65         struct slip_pre_exec_data *data = arg;
  66
  67         if(data->stdin >= 0) dup2(data->stdin, 0);
  68         dup2(data->stdout, 1);
  69         if(data->close_me >= 0) os_close_file(data->close_me);
  70 }
  71
  72 static int slip_tramp(char **argv, int fd)
  73 {
  74         struct slip_pre_exec_data pe_data;
  75         char *output;
  76         int status, pid, fds[2], err, output_len;
  77
  78         err = os_pipe(fds, 1, 0);
  79         if(err < 0){
  80                 printk("slip_tramp : pipe failed, err = %d\n", -err);
  81                 goto out;
  82         }
  83
  84         err = 0;
  85         pe_data.stdin = fd;
  86         pe_data.stdout = fds[1];
  87         pe_data.close_me = fds[0];
  88         err = run_helper(slip_pre_exec, &pe_data, argv, NULL);
  89         if(err < 0)
  90                 goto out_close;
  91         pid = err;
  92
  93         output_len = UM_KERN_PAGE_SIZE;
  94         output = um_kmalloc(output_len);
  95         if(output == NULL){
  96                 printk("slip_tramp : failed to allocate output buffer\n");
  97                 os_kill_process(pid, 1);
  98                 err = -ENOMEM;
  99                 goto out_free;
 100         }
 101
 102         os_close_file(fds[1]);
 103         read_output(fds[0], output, output_len);
 104         printk("%s", output);
 105
 106         CATCH_EINTR(err = waitpid(pid, &status, 0));
 107         if(err < 0)
 108                 err = errno;
 109         else if(!WIFEXITED(status) || (WEXITSTATUS(status) != 0)){
 110                 printk("'%s' didn't exit with status 0\n", argv[0]);
 111                 err = -EINVAL;
 112         }
 113         else err = 0;
 114
 115         os_close_file(fds[0]);
 116
 117 out_free:
 118         kfree(output);
 119         return err;
 120
 121 out_close:
 122         os_close_file(fds[0]);
 123         os_close_file(fds[1]);
 124 out:
 125         return err;
 126 }
 127
 128 static int slip_open(void *data)
 129 {
 130         struct slip_data *pri = data;
 131         char version_buf[sizeof("nnnnn\0")];
 132         char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
 133         char *argv[] = { "uml_net", version_buf, "slip", "up", gate_buf,
 134                          NULL };
 135         int sfd, mfd, err;
 136
 137         err = get_pty();
 138         if(err < 0){
 139                 printk("slip-open : Failed to open pty, err = %d\n", -err);
 140                 goto out;
 141         }
 142         mfd = err;
 143
 144         err = os_open_file(ptsname(mfd), of_rdwr(OPENFLAGS()), 0);
 145         if(err < 0){
 146                 printk("Couldn't open tty for slip line, err = %d\n", -err);
 147                 goto out_close;
 148         }
 149         sfd = err;
 150
 151         if(set_up_tty(sfd))
 152                 goto out_close2;
 153
 154         pri->slave = sfd;
 155         pri->slip.pos = 0;
 156         pri->slip.esc = 0;
 157         if(pri->gate_addr != NULL){
 158                 sprintf(version_buf, "%d", UML_NET_VERSION);
 159                 strcpy(gate_buf, pri->gate_addr);
 160
 161                 err = slip_tramp(argv, sfd);
 162
 163                 if(err < 0){
 164                         printk("slip_tramp failed - err = %d\n", -err);
 165                         goto out_close2;
 166                 }
 167                 err = os_get_ifname(pri->slave, pri->name);
 168                 if(err < 0){
 169                         printk("get_ifname failed, err = %d\n", -err);
 170                         goto out_close2;
 171                 }
 172                 iter_addresses(pri->dev, open_addr, pri->name);
 173         }
 174         else {
 175                 err = os_set_slip(sfd);
 176                 if(err < 0){
 177                         printk("Failed to set slip discipline encapsulation - "
 178                                "err = %d\n", -err);
 179                         goto out_close2;
 180                 }
 181         }
 182         return(mfd);
 183 out_close2:
 184         os_close_file(sfd);
 185 out_close:
 186         os_close_file(mfd);
 187 out:
 188         return err;
 189 }
 190
 191 static void slip_close(int fd, void *data)
 192 {
 193         struct slip_data *pri = data;
 194         char version_buf[sizeof("nnnnn\0")];
 195         char *argv[] = { "uml_net", version_buf, "slip", "down", pri->name,
 196                          NULL };
 197         int err;
 198
 199         if(pri->gate_addr != NULL)
 200                 iter_addresses(pri->dev, close_addr, pri->name);
 201
 202         sprintf(version_buf, "%d", UML_NET_VERSION);
 203
 204         err = slip_tramp(argv, pri->slave);
 205
 206         if(err != 0)
 207                 printk("slip_tramp failed - errno = %d\n", -err);
 208         os_close_file(fd);
 209         os_close_file(pri->slave);
 210         pri->slave = -1;
 211 }
 212
 213 int slip_user_read(int fd, void *buf, int len, struct slip_data *pri)
 214 {
 215         return slip_proto_read(fd, buf, len, &pri->slip);
 216 }
 217
 218 int slip_user_write(int fd, void *buf, int len, struct slip_data *pri)
 219 {
 220         return slip_proto_write(fd, buf, len, &pri->slip);
 221 }
 222
 223 static int slip_set_mtu(int mtu, void *data)
 224 {
 225         return(mtu);
 226 }
 227
 228 static void slip_add_addr(unsigned char *addr, unsigned char *netmask,
 229                           void *data)
 230 {
 231         struct slip_data *pri = data;
 232
 233         if(pri->slave < 0) return;
 234         open_addr(addr, netmask, pri->name);
 235 }
 236
 237 static void slip_del_addr(unsigned char *addr, unsigned char *netmask,
 238                             void *data)
 239 {
 240         struct slip_data *pri = data;
 241
 242         if(pri->slave < 0) return;
 243         close_addr(addr, netmask, pri->name);
 244 }
 245
 246 const struct net_user_info slip_user_info = {
 247         .init           = slip_user_init,
 248         .open           = slip_open,
 249         .close          = slip_close,
 250         .remove         = NULL,
 251         .set_mtu        = slip_set_mtu,
 252         .add_address    = slip_add_addr,
 253         .delete_address = slip_del_addr,
 254         .max_packet     = BUF_SIZE
 255 };