Usermode/Applications/telnetd_src/main.c

   1 /*
   2  * Acess2 Telnet Server (TCP server test case)
   3  * - By John Hodge (thePowersGang)
   4  *
   5  * main.c
   6  * - All
   7  */
   8 #include <stddef.h>
   9 #include <net.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <acess/sys.h>
  13 #include <assert.h>
  14 #include <errno.h>
  15 #include <acess/devices/pty.h>
  16
  17 // === TYPES ===
  18 enum eTelnetMode
  19 {
  20         MODE_DATA,
  21         MODE_IAC,
  22         MODE_WILL,
  23         MODE_WONT,
  24         MODE_DO,
  25         MODE_DONT
  26 };
  27
  28 typedef struct sClient
  29 {
  30         enum eTelnetMode        Mode;
  31          int    Socket;
  32          int    pty;
  33 } tClient;
  34
  35 // === PROTOTYPES ===
  36 void    EventLoop(void);
  37 void    Server_NewClient(int FD);
  38 void    HandleServerBoundData(tClient *Client);
  39 void    HandleClientBoundData(tClient *Client);
  40
  41 // === GLOBALS ===
  42 // --- Configuration ---
  43  int    giConfig_MaxClients = 5;
  44 // --- State ---
  45  int    giServerFD;
  46 tClient *gaClients;
  47  int    giNumClients;
  48
  49 // === CODE ===
  50 int main(int argc, char *argv[])
  51 {
  52         // TODO: Configure
  53
  54         // Initialise
  55         gaClients = calloc(giConfig_MaxClients, sizeof(tClient));
  56
  57         // Open server
  58         {
  59                 uint8_t data[16];
  60                  int    addrtype = Net_ParseAddress("10.0.2.10", data);
  61                  int    port = 23;
  62                 giServerFD = Net_OpenSocket(addrtype, data, "tcps");
  63                 _SysIOCtl(giServerFD, 4, &port);        // Set port and start listening
  64         }
  65
  66         // Event loop
  67         EventLoop();
  68
  69         return 0;
  70 }
  71
  72 static void FD_SET_MAX(fd_set *set, int fd, int *maxfd)
  73 {
  74         FD_SET(fd, set);
  75         if(*maxfd < fd) *maxfd = fd;
  76 }
  77
  78 void EventLoop(void)
  79 {
  80         fd_set  fds;
  81          int    maxfd;
  82
  83         for( ;; )
  84         {
  85                 FD_ZERO(&fds);
  86                 maxfd = 0;
  87                 // Fill select
  88                 FD_SET_MAX(&fds, giServerFD, &maxfd);
  89                 for( int i = 0; i < giConfig_MaxClients; i ++ )
  90                 {
  91                         if( gaClients[i].Socket == 0 )  continue ;
  92                         FD_SET_MAX(&fds, gaClients[i].Socket, &maxfd);
  93                         FD_SET_MAX(&fds, gaClients[i].pty,  &maxfd);
  94                 }
  95
  96                 // Select!
  97                 _SysSelect( maxfd+1, &fds, NULL, NULL, NULL, 0 );
  98
  99                 // Check events
 100                 if( FD_ISSET(giServerFD, &fds) )
 101                 {
 102                         Server_NewClient(giServerFD);
 103                 }
 104                 for( int i = 0; i < giConfig_MaxClients; i ++ )
 105                 {
 106                         if( FD_ISSET(gaClients[i].Socket, &fds) )
 107                         {
 108                                 // Handle client data
 109                                 HandleServerBoundData(&gaClients[i]);
 110                         }
 111                         if( FD_ISSET(gaClients[i].pty, &fds) )
 112                         {
 113                                 // Handle output from terminal
 114                                 HandleClientBoundData(&gaClients[i]);
 115                         }
 116                 }
 117         }
 118 }
 119
 120 void Server_NewClient(int FD)
 121 {
 122         tClient *clt = NULL;
 123
 124         // TODO: Is this done in the IPStack?
 125         if( giNumClients == giConfig_MaxClients )
 126         {
 127                 // Open, reject
 128                 _SysClose( _SysOpenChild(FD, "", OPENFLAG_READ) );
 129                 return ;
 130         }
 131
 132         // Allocate client structure and open socket
 133         for( int i = 0; i < giConfig_MaxClients; i ++ )
 134         {
 135                 if( gaClients[i].Socket == 0 ) {
 136                         clt = &gaClients[i];
 137                         break;
 138                 }
 139         }
 140         assert(clt);
 141         // Accept the connection
 142         clt->Socket = _SysOpenChild(FD, "", OPENFLAG_READ|OPENFLAG_WRITE);
 143         giNumClients ++;
 144
 145         // Create PTY
 146         // TODO: Use PTYs
 147         clt->pty = _SysOpen("/Devices/pts/ptmx", OPENFLAG_READ|OPENFLAG_WRITE);
 148         if( clt->pty < 0 ) {
 149                 perror("Unable to create/open PTY");
 150                 _SysDebug("Unable to create/open PTY: %s", strerror(errno));
 151                 _SysClose(clt->Socket);
 152                 clt->Socket = 0;
 153                 return ;
 154         }
 155         // - Initialise
 156         {
 157                 _SysIOCtl(clt->pty, PTY_IOCTL_SETID, "telnetd0");
 158                 struct ptymode  mode = {.InputMode = 0, .OutputMode=0};
 159                 struct ptydims  dims = {.W = 80, .H = 25};
 160                 _SysIOCtl(clt->pty, PTY_IOCTL_SETMODE, &mode);
 161                 _SysIOCtl(clt->pty, PTY_IOCTL_SETDIMS, &dims);
 162         }
 163
 164         // TODO: Arguments and envp
 165         {
 166                  int    clientfd = _SysOpen("/Devices/pts/telnetd0", OPENFLAG_READ|OPENFLAG_WRITE);
 167                 if(clientfd < 0) {
 168                         perror("Unable to open login PTY");
 169                         _SysClose(clt->Socket);
 170                         _SysClose(clt->pty);
 171                         clt->Socket = 0;
 172                         return ;
 173                 }
 174                 int fds[3] = {clientfd, clientfd, clientfd};
 175                 const char      *argv[] = {"login", NULL};
 176                 _SysSpawn("/Acess/SBin/login", argv, argv, 3, fds, NULL);
 177         }
 178 }
 179
 180 void HandleServerBoundData(tClient *Client)
 181 {
 182         uint8_t buf[BUFSIZ];
 183         size_t  len;
 184
 185         len = _SysRead(Client->Socket, buf, BUFSIZ);
 186         if( len == 0 )  return ;
 187         if( len == -1 ) {
 188                 return ;
 189         }
 190         // handle options
 191          int    last_flush = 0;
 192         for( int i = 0; i < len; i ++ )
 193         {
 194                 switch(Client->Mode)
 195                 {
 196                 case MODE_IAC:
 197                         Client->Mode = MODE_DATA;
 198                         switch(buf[i])
 199                         {
 200                         case 240:       // End of subnegotiation parameters
 201                                 _SysDebug("End Subnegotiation");
 202                                 break;
 203                         case 241:       // Nop
 204                                 break;
 205                         case 242:       // SYNCH
 206                         case 243:       // NVT Break
 207                         case 244:       // Function 'IP' (Ctrl-C)
 208
 209                                 break;
 210                         case 245:       // Function 'AO'
 211                         case 246:       // Function 'AYT'
 212                         case 247:       // Function 'EC'
 213                         case 248:       // Function 'EL'
 214                         case 249:       // GA Signal
 215                                 break;
 216                         case 250:       // Subnegotation
 217                                 _SysDebug("Subnegotiation");
 218                                 break;
 219                         case 251:       // WILL
 220                                 Client->Mode = MODE_WILL;
 221                                 break;
 222                         case 252:       // WONT
 223                                 Client->Mode = MODE_WONT;
 224                                 break;
 225                         case 253:       // DO
 226                                 Client->Mode = MODE_DO;
 227                                 break;
 228                         case 254:       // DONT
 229                                 Client->Mode = MODE_DONT;
 230                                 break;
 231                         case 255:       // Literal 255
 232                                 Client->Mode = MODE_DATA;
 233                                 i --;   // hacky!
 234                                 break;
 235                         }
 236                         break;
 237                 case MODE_WILL:
 238                         _SysDebug("Option %i WILL", buf[i]);
 239                         Client->Mode = MODE_DATA;
 240                         break;
 241                 case MODE_WONT:
 242                         _SysDebug("Option %i WONT", buf[i]);
 243                         Client->Mode = MODE_DATA;
 244                         break;
 245                 case MODE_DO:
 246                         _SysDebug("Option %i DO", buf[i]);
 247                         Client->Mode = MODE_DATA;
 248                         break;
 249                 case MODE_DONT:
 250                         _SysDebug("Option %i DONT", buf[i]);
 251                         Client->Mode = MODE_DATA;
 252                         break;
 253                 case MODE_DATA:
 254                         if( buf[i] == 255 )
 255                                 Client->Mode = MODE_IAC;
 256                         else
 257                                 _SysWrite(Client->pty, buf+i, 1);
 258                         break;
 259                 }
 260         }
 261 }
 262
 263 void HandleClientBoundData(tClient *Client)
 264 {
 265         char    buf[BUFSIZ];
 266          int    len;
 267
 268         len = _SysRead(Client->pty, buf, BUFSIZ);
 269         if( len <= 0 )  return ;
 270         _SysWrite(Client->Socket, buf, len);
 271 }
 272