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
  14 // === TYPES ===
  15 enum eTelnetMode
  16 {
  17         MODE_DATA,
  18         MODE_IAC,
  19         MODE_WILL,
  20         MODE_WONT,
  21         MODE_DO,
  22         MODE_DONT
  23 };
  24
  25 typedef struct sClient
  26 {
  27         enum eTelnetMode        Mode;
  28          int    Socket;
  29          int    pty;
  30 } tClient;
  31
  32 // === PROTOTYPES ===
  33 void    EventLoop(void);
  34 void    Server_NewClient(int FD);
  35 void    HandleServerBoundData(tClient *Client);
  36 void    HandleClientBoundData(tClient *Client);
  37
  38 // === GLOBALS ===
  39 // --- Configuration ---
  40  int    giConfig_MaxClients = 5;
  41 // --- State ---
  42  int    giServerFD;
  43 tClient *gaClients;
  44  int    giNumClients;
  45
  46 // === CODE ===
  47 int main(int argc, char *argv[])
  48 {
  49         // TODO: Configure
  50
  51         // Initialise
  52         gaClients = calloc(giConfig_MaxClients, sizeof(tClient));
  53
  54         // Open server
  55         {
  56                 uint8_t data[16];
  57                  int    addrtype = Net_ParseAddress("10.0.2.10", data);
  58                  int    port = 23;
  59                 giServerFD = Net_OpenSocket(addrtype, data, "tcps");
  60                 _SysIOCtl(giServerFD, 4, &port);        // Set port and start listening
  61         }
  62
  63         // Event loop
  64         EventLoop();
  65
  66         return 0;
  67 }
  68
  69 static void FD_SET_MAX(fd_set *set, int fd, int *maxfd)
  70 {
  71         FD_SET(fd, set);
  72         if(*maxfd < fd) *maxfd = fd;
  73 }
  74
  75 void EventLoop(void)
  76 {
  77         fd_set  fds;
  78          int    maxfd;
  79
  80         for( ;; )
  81         {
  82                 FD_ZERO(&fds);
  83                 maxfd = 0;
  84                 // Fill select
  85                 FD_SET_MAX(&fds, giServerFD, &maxfd);
  86                 for( int i = 0; i < giConfig_MaxClients; i ++ )
  87                 {
  88                         if( gaClients[i].Socket == 0 )  continue ;
  89                         _SysDebug("Socket = %i, pty = %i",
  90                                 gaClients[i].Socket, gaClients[i].pty);
  91                         FD_SET_MAX(&fds, gaClients[i].Socket, &maxfd);
  92                         FD_SET_MAX(&fds, gaClients[i].pty,  &maxfd);
  93                 }
  94
  95                 // Select!
  96                 _SysSelect( maxfd+1, &fds, NULL, NULL, NULL, 0 );
  97
  98                 // Check events
  99                 if( FD_ISSET(giServerFD, &fds) )
 100                 {
 101                         Server_NewClient(giServerFD);
 102                 }
 103                 for( int i = 0; i < giConfig_MaxClients; i ++ )
 104                 {
 105                         if( FD_ISSET(gaClients[i].Socket, &fds) )
 106                         {
 107                                 // Handle client data
 108                                 HandleServerBoundData(&gaClients[i]);
 109                         }
 110                         if( FD_ISSET(gaClients[i].pty, &fds) )
 111                         {
 112                                 // Handle output from terminal
 113                                 HandleClientBoundData(&gaClients[i]);
 114                         }
 115                 }
 116         }
 117 }
 118
 119 void Server_NewClient(int FD)
 120 {
 121         tClient *clt;
 122
 123         // TODO: Is this done in the IPStack?
 124         if( giNumClients == giConfig_MaxClients )
 125         {
 126                 // Open, reject
 127                 _SysClose( _SysOpenChild(FD, "", OPENFLAG_READ) );
 128                 return ;
 129         }
 130
 131         // Allocate client structure and open socket
 132         for( int i = 0; i < giConfig_MaxClients; i ++ )
 133         {
 134                 if( gaClients[i].Socket == 0 ) {
 135                         clt = &gaClients[i];
 136                         break;
 137                 }
 138         }
 139         // Accept the connection
 140         clt->Socket = _SysOpenChild(FD, "", OPENFLAG_READ|OPENFLAG_WRITE);
 141         giNumClients ++;
 142
 143         // Create stdin/stdout
 144         // - Current PTY code is strange with mknod
 145         clt->pty = _SysOpen("/Devices/pts/telnetd0", OPENFLAG_CREATE|OPENFLAG_READ|OPENFLAG_WRITE);
 146         if( clt->pty < 0 ) {
 147                 perror("Unable to open server PTY");
 148                 _SysClose(clt->Socket);
 149                 clt->Socket = 0;
 150                 return ;
 151         }
 152
 153         // TODO: Arguments and envp
 154         {
 155                  int    clientfd = _SysOpen("/Devices/pts/telnetd0c", OPENFLAG_READ|OPENFLAG_WRITE);
 156                 if(clientfd < 0) {
 157                         perror("Unable to open login PTY");
 158                         _SysClose(clt->Socket);
 159                         _SysClose(clt->pty);
 160                         clt->Socket = 0;
 161                         return ;
 162                 }
 163                 int fds[3] = {clientfd, clientfd, clientfd};
 164                 const char      *argv[] = {"login", NULL};
 165                 _SysSpawn("/Acess/SBin/login", argv, argv, 3, fds, NULL);
 166         }
 167 }
 168
 169 void HandleServerBoundData(tClient *Client)
 170 {
 171         uint8_t buf[BUFSIZ];
 172         size_t  len;
 173
 174         len = _SysRead(Client->Socket, buf, BUFSIZ);
 175         if( len == 0 )  return ;
 176         if( len == -1 ) {
 177                 return ;
 178         }
 179         // handle options
 180          int    last_flush = 0;
 181         for( int i = 0; i < len; i ++ )
 182         {
 183                 switch(Client->Mode)
 184                 {
 185                 case MODE_IAC:
 186                         Client->Mode = MODE_DATA;
 187                         switch(buf[i])
 188                         {
 189                         case 240:       // End of subnegotiation parameters
 190                         case 241:       // Nop
 191                                 break;
 192                         case 242:       // SYNCH
 193                         case 243:       // NVT Break
 194                         case 244:       // Function 'IP' (Ctrl-C)
 195
 196                                 break;
 197                         case 245:       // Function 'AO'
 198                         case 246:       // Function 'AYT'
 199                         case 247:       // Function 'EC'
 200                         case 248:       // Function 'EL'
 201                         case 249:       // GA Signal
 202                         case 250:       // Subnegotation
 203                                 break;
 204                         case 251:       // WILL
 205                                 Client->Mode = MODE_WILL;
 206                                 break;
 207                         case 252:       // WONT
 208                                 Client->Mode = MODE_WILL;
 209                                 break;
 210                         case 253:       // DO
 211                                 Client->Mode = MODE_WILL;
 212                                 break;
 213                         case 254:       // DONT
 214                                 Client->Mode = MODE_WILL;
 215                                 break;
 216                         case 255:       // Literal 255
 217                                 Client->Mode = MODE_DATA;
 218                                 i --;   // hacky!
 219                                 break;
 220                         }
 221                         break;
 222                 case MODE_WILL:
 223                         _SysDebug("Option %i WILL", buf[i]);
 224                         Client->Mode = MODE_DATA;
 225                         break;
 226                 case MODE_WONT:
 227                         _SysDebug("Option %i WONT", buf[i]);
 228                         Client->Mode = MODE_DATA;
 229                         break;
 230                 case MODE_DO:
 231                         _SysDebug("Option %i DO", buf[i]);
 232                         Client->Mode = MODE_DATA;
 233                         break;
 234                 case MODE_DONT:
 235                         _SysDebug("Option %i DONT", buf[i]);
 236                         Client->Mode = MODE_DATA;
 237                         break;
 238                 case MODE_DATA:
 239                         if( buf[i] == 255 )
 240                                 Client->Mode = MODE_IAC;
 241                         else
 242                                 _SysWrite(Client->pty, buf+i, 1);
 243                         break;
 244                 }
 245         }
 246 }
 247
 248 void HandleClientBoundData(tClient *Client)
 249 {
 250         char    buf[BUFSIZ];
 251          int    len;
 252
 253         len = _SysRead(Client->pty, buf, BUFSIZ);
 254         if( len <= 0 )  return ;
 255         _SysWrite(Client->Socket, buf, len);
 256 }
 257