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 "user_util.h"
  12 #include "kern_util.h"
  13 #include "user.h"
  14 #include "net_user.h"
  15 #include "slip.h"
  16 #include "slip_proto.h"
  17 #include "helper.h"
  18 #include "os.h"
  19
  20 void slip_user_init(void *data, void *dev)
  21 {
  22         struct slip_data *pri = data;
  23
  24         pri->dev = dev;
  25 }
  26
  27 static int set_up_tty(int fd)
  28 {
  29         int i;
  30         struct termios tios;
  31
  32         if (tcgetattr(fd, &tios) < 0) {
  33                 printk("could not get initial terminal attributes\n");
  34                 return(-1);
  35         }
  36
  37         tios.c_cflag = CS8 | CREAD | HUPCL | CLOCAL;
  38         tios.c_iflag = IGNBRK | IGNPAR;
  39         tios.c_oflag = 0;
  40         tios.c_lflag = 0;
  41         for (i = 0; i < NCCS; i++)
  42                 tios.c_cc[i] = 0;
  43         tios.c_cc[VMIN] = 1;
  44         tios.c_cc[VTIME] = 0;
  45
  46         cfsetospeed(&tios, B38400);
  47         cfsetispeed(&tios, B38400);
  48
  49         if (tcsetattr(fd, TCSAFLUSH, &tios) < 0) {
  50                 printk("failed to set terminal attributes\n");
  51                 return(-1);
  52         }
  53         return(0);
  54 }
  55
  56 struct slip_pre_exec_data {
  57         int stdin;
  58         int stdout;
  59         int close_me;
  60 };
  61
  62 static void slip_pre_exec(void *arg)
  63 {
  64         struct slip_pre_exec_data *data = arg;
  65
  66         if(data->stdin >= 0) dup2(data->stdin, 0);
  67         dup2(data->stdout, 1);
  68         if(data->close_me >= 0) os_close_file(data->close_me);
  69 }
  70
  71 static int slip_tramp(char **argv, int fd)
  72 {
  73         struct slip_pre_exec_data pe_data;
  74         char *output;
  75         int status, pid, fds[2], err, output_len;
  76
  77         err = os_pipe(fds, 1, 0);
  78         if(err < 0){
  79                 printk("slip_tramp : pipe failed, err = %d\n", -err);
  80                 return(err);
  81         }
  82
  83         err = 0;
  84         pe_data.stdin = fd;
  85         pe_data.stdout = fds[1];
  86         pe_data.close_me = fds[0];
  87         pid = run_helper(slip_pre_exec, &pe_data, argv, NULL);
  88
  89         if(pid < 0) err = pid;
  90         else {
  91                 output_len = page_size();
  92                 output = um_kmalloc(output_len);
  93                 if(output == NULL)
  94                         printk("slip_tramp : failed to allocate output "
  95                                "buffer\n");
  96
  97                 os_close_file(fds[1]);
  98                 read_output(fds[0], output, output_len);
  99                 if(output != NULL){
 100                         printk("%s", output);
 101                         kfree(output);
 102                 }
 103                 CATCH_EINTR(err = waitpid(pid, &status, 0));
 104                 if(err < 0)
 105                         err = errno;
 106                 else if(!WIFEXITED(status) || (WEXITSTATUS(status) != 0)){
 107                         printk("'%s' didn't exit with status 0\n", argv[0]);
 108                         err = -EINVAL;
 109                 }
 110         }
 111         return(err);
 112 }
 113
 114 static int slip_open(void *data)
 115 {
 116         struct slip_data *pri = data;
 117         char version_buf[sizeof("nnnnn\0")];
 118         char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
 119         char *argv[] = { "uml_net", version_buf, "slip", "up", gate_buf,
 120                          NULL };
 121         int sfd, mfd, err;
 122
 123         mfd = get_pty();
 124         if(mfd < 0){
 125                 printk("umn : Failed to open pty, err = %d\n", -mfd);
 126                 return(mfd);
 127         }
 128         sfd = os_open_file(ptsname(mfd), of_rdwr(OPENFLAGS()), 0);
 129         if(sfd < 0){
 130                 printk("Couldn't open tty for slip line, err = %d\n", -sfd);
 131                 return(sfd);
 132         }
 133         if(set_up_tty(sfd)) return(-1);
 134         pri->slave = sfd;
 135         pri->pos = 0;
 136         pri->esc = 0;
 137         if(pri->gate_addr != NULL){
 138                 sprintf(version_buf, "%d", UML_NET_VERSION);
 139                 strcpy(gate_buf, pri->gate_addr);
 140
 141                 err = slip_tramp(argv, sfd);
 142
 143                 if(err < 0){
 144                         printk("slip_tramp failed - err = %d\n", -err);
 145                         return(err);
 146                 }
 147                 err = os_get_ifname(pri->slave, pri->name);
 148                 if(err < 0){
 149                         printk("get_ifname failed, err = %d\n", -err);
 150                         return(err);
 151                 }
 152                 iter_addresses(pri->dev, open_addr, pri->name);
 153         }
 154         else {
 155                 err = os_set_slip(sfd);
 156                 if(err < 0){
 157                         printk("Failed to set slip discipline encapsulation - "
 158                                "err = %d\n", -err);
 159                         return(err);
 160                 }
 161         }
 162         return(mfd);
 163 }
 164
 165 static void slip_close(int fd, void *data)
 166 {
 167         struct slip_data *pri = data;
 168         char version_buf[sizeof("nnnnn\0")];
 169         char *argv[] = { "uml_net", version_buf, "slip", "down", pri->name,
 170                          NULL };
 171         int err;
 172
 173         if(pri->gate_addr != NULL)
 174                 iter_addresses(pri->dev, close_addr, pri->name);
 175
 176         sprintf(version_buf, "%d", UML_NET_VERSION);
 177
 178         err = slip_tramp(argv, -1);
 179
 180         if(err != 0)
 181                 printk("slip_tramp failed - errno = %d\n", -err);
 182         os_close_file(fd);
 183         os_close_file(pri->slave);
 184         pri->slave = -1;
 185 }
 186
 187 int slip_user_read(int fd, void *buf, int len, struct slip_data *pri)
 188 {
 189         int i, n, size, start;
 190
 191         if(pri->more>0) {
 192                 i = 0;
 193                 while(i < pri->more) {
 194                         size = slip_unesc(pri->ibuf[i++],
 195                                         pri->ibuf, &pri->pos, &pri->esc);
 196                         if(size){
 197                                 memcpy(buf, pri->ibuf, size);
 198                                 memmove(pri->ibuf, &pri->ibuf[i], pri->more-i);
 199                                 pri->more=pri->more-i;
 200                                 return(size);
 201                         }
 202                 }
 203                 pri->more=0;
 204         }
 205
 206         n = net_read(fd, &pri->ibuf[pri->pos], sizeof(pri->ibuf) - pri->pos);
 207         if(n <= 0) return(n);
 208
 209         start = pri->pos;
 210         for(i = 0; i < n; i++){
 211                 size = slip_unesc(pri->ibuf[start + i],
 212                                 pri->ibuf, &pri->pos, &pri->esc);
 213                 if(size){
 214                         memcpy(buf, pri->ibuf, size);
 215                         memmove(pri->ibuf, &pri->ibuf[start+i+1], n-(i+1));
 216                         pri->more=n-(i+1);
 217                         return(size);
 218                 }
 219         }
 220         return(0);
 221 }
 222
 223 int slip_user_write(int fd, void *buf, int len, struct slip_data *pri)
 224 {
 225         int actual, n;
 226
 227         actual = slip_esc(buf, pri->obuf, len);
 228         n = net_write(fd, pri->obuf, actual);
 229         if(n < 0) return(n);
 230         else return(len);
 231 }
 232
 233 static int slip_set_mtu(int mtu, void *data)
 234 {
 235         return(mtu);
 236 }
 237
 238 static void slip_add_addr(unsigned char *addr, unsigned char *netmask,
 239                           void *data)
 240 {
 241         struct slip_data *pri = data;
 242
 243         if(pri->slave < 0) return;
 244         open_addr(addr, netmask, pri->name);
 245 }
 246
 247 static void slip_del_addr(unsigned char *addr, unsigned char *netmask,
 248                             void *data)
 249 {
 250         struct slip_data *pri = data;
 251
 252         if(pri->slave < 0) return;
 253         close_addr(addr, netmask, pri->name);
 254 }
 255
 256 struct net_user_info slip_user_info = {
 257         .init           = slip_user_init,
 258         .open           = slip_open,
 259         .close          = slip_close,
 260         .remove         = NULL,
 261         .set_mtu        = slip_set_mtu,
 262         .add_address    = slip_add_addr,
 263         .delete_address = slip_del_addr,
 264         .max_packet     = BUF_SIZE
 265 };
 266
 267 /*
 268  * Overrides for Emacs so that we follow Linus's tabbing style.
 269  * Emacs will notice this stuff at the end of the file and automatically
 270  * adjust the settings for this buffer only.  This must remain at the end
 271  * of the file.
 272  * ---------------------------------------------------------------------------
 273  * Local variables:
 274  * c-file-style: "linux"
 275  * End:
 276  */