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