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
 112         os_close_file(fds[0]);
 113
 114         return(err);
 115 }
 116
 117 static int slip_open(void *data)
 118 {
 119         struct slip_data *pri = data;
 120         char version_buf[sizeof("nnnnn\0")];
 121         char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
 122         char *argv[] = { "uml_net", version_buf, "slip", "up", gate_buf,
 123                          NULL };
 124         int sfd, mfd, err;
 125
 126         mfd = get_pty();
 127         if(mfd < 0){
 128                 printk("umn : Failed to open pty, err = %d\n", -mfd);
 129                 return(mfd);
 130         }
 131         sfd = os_open_file(ptsname(mfd), of_rdwr(OPENFLAGS()), 0);
 132         if(sfd < 0){
 133                 printk("Couldn't open tty for slip line, err = %d\n", -sfd);
 134                 os_close_file(mfd);
 135                 return(sfd);
 136         }
 137         if(set_up_tty(sfd)) return(-1);
 138         pri->slave = sfd;
 139         pri->pos = 0;
 140         pri->esc = 0;
 141         if(pri->gate_addr != NULL){
 142                 sprintf(version_buf, "%d", UML_NET_VERSION);
 143                 strcpy(gate_buf, pri->gate_addr);
 144
 145                 err = slip_tramp(argv, sfd);
 146
 147                 if(err < 0){
 148                         printk("slip_tramp failed - err = %d\n", -err);
 149                         return(err);
 150                 }
 151                 err = os_get_ifname(pri->slave, pri->name);
 152                 if(err < 0){
 153                         printk("get_ifname failed, err = %d\n", -err);
 154                         return(err);
 155                 }
 156                 iter_addresses(pri->dev, open_addr, pri->name);
 157         }
 158         else {
 159                 err = os_set_slip(sfd);
 160                 if(err < 0){
 161                         printk("Failed to set slip discipline encapsulation - "
 162                                "err = %d\n", -err);
 163                         return(err);
 164                 }
 165         }
 166         return(mfd);
 167 }
 168
 169 static void slip_close(int fd, void *data)
 170 {
 171         struct slip_data *pri = data;
 172         char version_buf[sizeof("nnnnn\0")];
 173         char *argv[] = { "uml_net", version_buf, "slip", "down", pri->name,
 174                          NULL };
 175         int err;
 176
 177         if(pri->gate_addr != NULL)
 178                 iter_addresses(pri->dev, close_addr, pri->name);
 179
 180         sprintf(version_buf, "%d", UML_NET_VERSION);
 181
 182         err = slip_tramp(argv, pri->slave);
 183
 184         if(err != 0)
 185                 printk("slip_tramp failed - errno = %d\n", -err);
 186         os_close_file(fd);
 187         os_close_file(pri->slave);
 188         pri->slave = -1;
 189 }
 190
 191 int slip_user_read(int fd, void *buf, int len, struct slip_data *pri)
 192 {
 193         int i, n, size, start;
 194
 195         if(pri->more>0) {
 196                 i = 0;
 197                 while(i < pri->more) {
 198                         size = slip_unesc(pri->ibuf[i++],
 199                                         pri->ibuf, &pri->pos, &pri->esc);
 200                         if(size){
 201                                 memcpy(buf, pri->ibuf, size);
 202                                 memmove(pri->ibuf, &pri->ibuf[i], pri->more-i);
 203                                 pri->more=pri->more-i;
 204                                 return(size);
 205                         }
 206                 }
 207                 pri->more=0;
 208         }
 209
 210         n = net_read(fd, &pri->ibuf[pri->pos], sizeof(pri->ibuf) - pri->pos);
 211         if(n <= 0) return(n);
 212
 213         start = pri->pos;
 214         for(i = 0; i < n; i++){
 215                 size = slip_unesc(pri->ibuf[start + i],
 216                                 pri->ibuf, &pri->pos, &pri->esc);
 217                 if(size){
 218                         memcpy(buf, pri->ibuf, size);
 219                         memmove(pri->ibuf, &pri->ibuf[start+i+1], n-(i+1));
 220                         pri->more=n-(i+1);
 221                         return(size);
 222                 }
 223         }
 224         return(0);
 225 }
 226
 227 int slip_user_write(int fd, void *buf, int len, struct slip_data *pri)
 228 {
 229         int actual, n;
 230
 231         actual = slip_esc(buf, pri->obuf, len);
 232         n = net_write(fd, pri->obuf, actual);
 233         if(n < 0) return(n);
 234         else return(len);
 235 }
 236
 237 static int slip_set_mtu(int mtu, void *data)
 238 {
 239         return(mtu);
 240 }
 241
 242 static void slip_add_addr(unsigned char *addr, unsigned char *netmask,
 243                           void *data)
 244 {
 245         struct slip_data *pri = data;
 246
 247         if(pri->slave < 0) return;
 248         open_addr(addr, netmask, pri->name);
 249 }
 250
 251 static void slip_del_addr(unsigned char *addr, unsigned char *netmask,
 252                             void *data)
 253 {
 254         struct slip_data *pri = data;
 255
 256         if(pri->slave < 0) return;
 257         close_addr(addr, netmask, pri->name);
 258 }
 259
 260 struct net_user_info slip_user_info = {
 261         .init           = slip_user_init,
 262         .open           = slip_open,
 263         .close          = slip_close,
 264         .remove         = NULL,
 265         .set_mtu        = slip_set_mtu,
 266         .add_address    = slip_add_addr,
 267         .delete_address = slip_del_addr,
 268         .max_packet     = BUF_SIZE
 269 };
 270
 271 /*
 272  * Overrides for Emacs so that we follow Linus's tabbing style.
 273  * Emacs will notice this stuff at the end of the file and automatically
 274  * adjust the settings for this buffer only.  This must remain at the end
 275  * of the file.
 276  * ---------------------------------------------------------------------------
 277  * Local variables:
 278  * c-file-style: "linux"
 279  * End:
 280  */