git.distorted.org.uk Git - u/mdw/putty/blob - rlogin.c

   1 #include <windows.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <ctype.h>
   5
   6 #include "putty.h"
   7
   8 #ifndef FALSE
   9 #define FALSE 0
  10 #endif
  11 #ifndef TRUE
  12 #define TRUE 1
  13 #endif
  14
  15 static Socket s = NULL;
  16
  17 static void rlogin_size(void);
  18
  19 static void c_write(char *buf, int len)
  20 {
  21     from_backend(0, buf, len);
  22 }
  23
  24 static int rlogin_closing(Plug plug, char *error_msg, int error_code,
  25                           int calling_back)
  26 {
  27     sk_close(s);
  28     s = NULL;
  29     if (error_msg) {
  30         /* A socket error has occurred. */
  31         connection_fatal(error_msg);
  32     }                                  /* Otherwise, the remote side closed the connection normally. */
  33     return 0;
  34 }
  35
  36 static int rlogin_receive(Plug plug, int urgent, char *data, int len)
  37 {
  38     if (urgent == 2) {
  39         char c;
  40
  41         c = *data++;
  42         len--;
  43         if (c == '\x80')
  44             rlogin_size();
  45         /*
  46          * We should flush everything (aka Telnet SYNCH) if we see
  47          * 0x02, and we should turn off and on _local_ flow control
  48          * on 0x10 and 0x20 respectively. I'm not convinced it's
  49          * worth it...
  50          */
  51     } else {
  52         /*
  53          * Main rlogin protocol. This is really simple: the first
  54          * byte is expected to be NULL and is ignored, and the rest
  55          * is printed.
  56          */
  57         static int firstbyte = 1;
  58         if (firstbyte) {
  59             if (data[0] == '\0') {
  60                 data++;
  61                 len--;
  62             }
  63             firstbyte = 0;
  64         }
  65         c_write(data, len);
  66     }
  67     return 1;
  68 }
  69
  70 /*
  71  * Called to set up the rlogin connection.
  72  *
  73  * Returns an error message, or NULL on success.
  74  *
  75  * Also places the canonical host name into `realhost'. It must be
  76  * freed by the caller.
  77  */
  78 static char *rlogin_init(char *host, int port, char **realhost)
  79 {
  80     static struct plug_function_table fn_table = {
  81         rlogin_closing,
  82         rlogin_receive
  83     }, *fn_table_ptr = &fn_table;
  84
  85     SockAddr addr;
  86     char *err;
  87
  88     /*
  89      * Try to find host.
  90      */
  91     addr = sk_namelookup(host, realhost);
  92     if ((err = sk_addr_error(addr)))
  93         return err;
  94
  95     if (port < 0)
  96         port = 513;                    /* default rlogin port */
  97
  98     /*
  99      * Open socket.
 100      */
 101     s = sk_new(addr, port, 1, 0, &fn_table_ptr);
 102     if ((err = sk_socket_error(s)))
 103         return err;
 104
 105     sk_addr_free(addr);
 106
 107     /*
 108      * Send local username, remote username, terminal/speed
 109      */
 110
 111     {
 112         char z = 0;
 113         char *p;
 114         sk_write(s, &z, 1);
 115         sk_write(s, cfg.localusername, strlen(cfg.localusername));
 116         sk_write(s, &z, 1);
 117         sk_write(s, cfg.username, strlen(cfg.username));
 118         sk_write(s, &z, 1);
 119         sk_write(s, cfg.termtype, strlen(cfg.termtype));
 120         sk_write(s, "/", 1);
 121         for (p = cfg.termspeed; isdigit(*p); p++);
 122         sk_write(s, cfg.termspeed, p - cfg.termspeed);
 123         sk_write(s, &z, 1);
 124     }
 125
 126     return NULL;
 127 }
 128
 129 /*
 130  * Called to send data down the rlogin connection.
 131  */
 132 static void rlogin_send(char *buf, int len)
 133 {
 134
 135     if (s == NULL)
 136         return;
 137
 138     sk_write(s, buf, len);
 139 }
 140
 141 /*
 142  * Called to set the size of the window
 143  */
 144 static void rlogin_size(void)
 145 {
 146     char b[12] = { '\xFF', '\xFF', 0x73, 0x73, 0, 0, 0, 0, 0, 0, 0, 0 };
 147
 148     b[6] = cols >> 8;
 149     b[7] = cols & 0xFF;
 150     b[4] = rows >> 8;
 151     b[5] = rows & 0xFF;
 152     sk_write(s, b, 12);
 153     return;
 154 }
 155
 156 /*
 157  * Send rlogin special codes.
 158  */
 159 static void rlogin_special(Telnet_Special code)
 160 {
 161     /* Do nothing! */
 162     return;
 163 }
 164
 165 static Socket rlogin_socket(void)
 166 {
 167     return s;
 168 }
 169
 170 static int rlogin_sendok(void)
 171 {
 172     return 1;
 173 }
 174
 175 static int rlogin_ldisc(int option)
 176 {
 177     return 0;
 178 }
 179
 180 Backend rlogin_backend = {
 181     rlogin_init,
 182     rlogin_send,
 183     rlogin_size,
 184     rlogin_special,
 185     rlogin_socket,
 186     rlogin_sendok,
 187     rlogin_ldisc,
 188     1
 189 };