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 #include "terminal.h"
   8
   9 #ifndef FALSE
  10 #define FALSE 0
  11 #endif
  12 #ifndef TRUE
  13 #define TRUE 1
  14 #endif
  15
  16 #define RLOGIN_MAX_BACKLOG 4096
  17
  18 static Socket s = NULL;
  19 static int rlogin_bufsize;
  20 static void *frontend;
  21
  22 static void rlogin_size(void);
  23
  24 static void c_write(char *buf, int len)
  25 {
  26     int backlog = from_backend(frontend, 0, buf, len);
  27     sk_set_frozen(s, backlog > RLOGIN_MAX_BACKLOG);
  28 }
  29
  30 static int rlogin_closing(Plug plug, char *error_msg, int error_code,
  31                           int calling_back)
  32 {
  33     if (s) {
  34         sk_close(s);
  35         s = NULL;
  36     }
  37     if (error_msg) {
  38         /* A socket error has occurred. */
  39         logevent(error_msg);
  40         connection_fatal("%s", error_msg);
  41     }                                  /* Otherwise, the remote side closed the connection normally. */
  42     return 0;
  43 }
  44
  45 static int rlogin_receive(Plug plug, int urgent, char *data, int len)
  46 {
  47     if (urgent == 2) {
  48         char c;
  49
  50         c = *data++;
  51         len--;
  52         if (c == '\x80')
  53             rlogin_size();
  54         /*
  55          * We should flush everything (aka Telnet SYNCH) if we see
  56          * 0x02, and we should turn off and on _local_ flow control
  57          * on 0x10 and 0x20 respectively. I'm not convinced it's
  58          * worth it...
  59          */
  60     } else {
  61         /*
  62          * Main rlogin protocol. This is really simple: the first
  63          * byte is expected to be NULL and is ignored, and the rest
  64          * is printed.
  65          */
  66         static int firstbyte = 1;
  67         if (firstbyte) {
  68             if (data[0] == '\0') {
  69                 data++;
  70                 len--;
  71             }
  72             firstbyte = 0;
  73         }
  74         if (len > 0)
  75             c_write(data, len);
  76     }
  77     return 1;
  78 }
  79
  80 static void rlogin_sent(Plug plug, int bufsize)
  81 {
  82     rlogin_bufsize = bufsize;
  83 }
  84
  85 /*
  86  * Called to set up the rlogin connection.
  87  *
  88  * Returns an error message, or NULL on success.
  89  *
  90  * Also places the canonical host name into `realhost'. It must be
  91  * freed by the caller.
  92  */
  93 static char *rlogin_init(void *frontend_handle,
  94                          char *host, int port, char **realhost, int nodelay)
  95 {
  96     static struct plug_function_table fn_table = {
  97         rlogin_closing,
  98         rlogin_receive,
  99         rlogin_sent
 100     }, *fn_table_ptr = &fn_table;
 101
 102     SockAddr addr;
 103     char *err;
 104
 105     frontend = frontend_handle;
 106
 107     /*
 108      * Try to find host.
 109      */
 110     {
 111         char buf[200];
 112         sprintf(buf, "Looking up host \"%.170s\"", host);
 113         logevent(buf);
 114     }
 115     addr = sk_namelookup(host, realhost);
 116     if ((err = sk_addr_error(addr)))
 117         return err;
 118
 119     if (port < 0)
 120         port = 513;                    /* default rlogin port */
 121
 122     /*
 123      * Open socket.
 124      */
 125     {
 126         char buf[200], addrbuf[100];
 127         sk_getaddr(addr, addrbuf, 100);
 128         sprintf(buf, "Connecting to %.100s port %d", addrbuf, port);
 129         logevent(buf);
 130     }
 131     s = new_connection(addr, *realhost, port, 1, 0, nodelay, &fn_table_ptr);
 132     if ((err = sk_socket_error(s)))
 133         return err;
 134
 135     sk_addr_free(addr);
 136
 137     /*
 138      * Send local username, remote username, terminal/speed
 139      */
 140
 141     {
 142         char z = 0;
 143         char *p;
 144         sk_write(s, &z, 1);
 145         sk_write(s, cfg.localusername, strlen(cfg.localusername));
 146         sk_write(s, &z, 1);
 147         sk_write(s, cfg.username, strlen(cfg.username));
 148         sk_write(s, &z, 1);
 149         sk_write(s, cfg.termtype, strlen(cfg.termtype));
 150         sk_write(s, "/", 1);
 151         for (p = cfg.termspeed; isdigit(*p); p++);
 152         sk_write(s, cfg.termspeed, p - cfg.termspeed);
 153         rlogin_bufsize = sk_write(s, &z, 1);
 154     }
 155
 156     return NULL;
 157 }
 158
 159 /*
 160  * Called to send data down the rlogin connection.
 161  */
 162 static int rlogin_send(char *buf, int len)
 163 {
 164     if (s == NULL)
 165         return 0;
 166
 167     rlogin_bufsize = sk_write(s, buf, len);
 168
 169     return rlogin_bufsize;
 170 }
 171
 172 /*
 173  * Called to query the current socket sendability status.
 174  */
 175 static int rlogin_sendbuffer(void)
 176 {
 177     return rlogin_bufsize;
 178 }
 179
 180 /*
 181  * Called to set the size of the window
 182  */
 183 static void rlogin_size(void)
 184 {
 185     char b[12] = { '\xFF', '\xFF', 0x73, 0x73, 0, 0, 0, 0, 0, 0, 0, 0 };
 186
 187     if (s == NULL || term == NULL)
 188         return;
 189
 190     b[6] = term->cols >> 8;
 191     b[7] = term->cols & 0xFF;
 192     b[4] = term->rows >> 8;
 193     b[5] = term->rows & 0xFF;
 194     rlogin_bufsize = sk_write(s, b, 12);
 195     return;
 196 }
 197
 198 /*
 199  * Send rlogin special codes.
 200  */
 201 static void rlogin_special(Telnet_Special code)
 202 {
 203     /* Do nothing! */
 204     return;
 205 }
 206
 207 static Socket rlogin_socket(void)
 208 {
 209     return s;
 210 }
 211
 212 static int rlogin_sendok(void)
 213 {
 214     return 1;
 215 }
 216
 217 static void rlogin_unthrottle(int backlog)
 218 {
 219     sk_set_frozen(s, backlog > RLOGIN_MAX_BACKLOG);
 220 }
 221
 222 static int rlogin_ldisc(int option)
 223 {
 224     return 0;
 225 }
 226
 227 static int rlogin_exitcode(void)
 228 {
 229     /* If we ever implement RSH, we'll probably need to do this properly */
 230     return 0;
 231 }
 232
 233 Backend rlogin_backend = {
 234     rlogin_init,
 235     rlogin_send,
 236     rlogin_sendbuffer,
 237     rlogin_size,
 238     rlogin_special,
 239     rlogin_socket,
 240     rlogin_exitcode,
 241     rlogin_sendok,
 242     rlogin_ldisc,
 243     rlogin_unthrottle,
 244     1
 245 };