| 1 | /* |
| 2 | * Rlogin backend. |
| 3 | */ |
| 4 | |
| 5 | #include <stdio.h> |
| 6 | #include <stdlib.h> |
| 7 | #include <ctype.h> |
| 8 | |
| 9 | #include "putty.h" |
| 10 | |
| 11 | #ifndef FALSE |
| 12 | #define FALSE 0 |
| 13 | #endif |
| 14 | #ifndef TRUE |
| 15 | #define TRUE 1 |
| 16 | #endif |
| 17 | |
| 18 | #define RLOGIN_MAX_BACKLOG 4096 |
| 19 | |
| 20 | typedef struct rlogin_tag { |
| 21 | const struct plug_function_table *fn; |
| 22 | /* the above field _must_ be first in the structure */ |
| 23 | |
| 24 | Socket s; |
| 25 | int bufsize; |
| 26 | int firstbyte; |
| 27 | int cansize; |
| 28 | int term_width, term_height; |
| 29 | void *frontend; |
| 30 | } *Rlogin; |
| 31 | |
| 32 | static void rlogin_size(void *handle, int width, int height); |
| 33 | |
| 34 | static void c_write(Rlogin rlogin, char *buf, int len) |
| 35 | { |
| 36 | int backlog = from_backend(rlogin->frontend, 0, buf, len); |
| 37 | sk_set_frozen(rlogin->s, backlog > RLOGIN_MAX_BACKLOG); |
| 38 | } |
| 39 | |
| 40 | static void rlogin_log(Plug plug, int type, SockAddr addr, int port, |
| 41 | const char *error_msg, int error_code) |
| 42 | { |
| 43 | Rlogin rlogin = (Rlogin) plug; |
| 44 | char addrbuf[256], *msg; |
| 45 | |
| 46 | sk_getaddr(addr, addrbuf, lenof(addrbuf)); |
| 47 | |
| 48 | if (type == 0) |
| 49 | msg = dupprintf("Connecting to %s port %d", addrbuf, port); |
| 50 | else |
| 51 | msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg); |
| 52 | |
| 53 | logevent(rlogin->frontend, msg); |
| 54 | } |
| 55 | |
| 56 | static int rlogin_closing(Plug plug, const char *error_msg, int error_code, |
| 57 | int calling_back) |
| 58 | { |
| 59 | Rlogin rlogin = (Rlogin) plug; |
| 60 | if (rlogin->s) { |
| 61 | sk_close(rlogin->s); |
| 62 | rlogin->s = NULL; |
| 63 | notify_remote_exit(rlogin->frontend); |
| 64 | } |
| 65 | if (error_msg) { |
| 66 | /* A socket error has occurred. */ |
| 67 | logevent(rlogin->frontend, error_msg); |
| 68 | connection_fatal(rlogin->frontend, "%s", error_msg); |
| 69 | } /* Otherwise, the remote side closed the connection normally. */ |
| 70 | return 0; |
| 71 | } |
| 72 | |
| 73 | static int rlogin_receive(Plug plug, int urgent, char *data, int len) |
| 74 | { |
| 75 | Rlogin rlogin = (Rlogin) plug; |
| 76 | if (urgent == 2) { |
| 77 | char c; |
| 78 | |
| 79 | c = *data++; |
| 80 | len--; |
| 81 | if (c == '\x80') { |
| 82 | rlogin->cansize = 1; |
| 83 | rlogin_size(rlogin, rlogin->term_width, rlogin->term_height); |
| 84 | } |
| 85 | /* |
| 86 | * We should flush everything (aka Telnet SYNCH) if we see |
| 87 | * 0x02, and we should turn off and on _local_ flow control |
| 88 | * on 0x10 and 0x20 respectively. I'm not convinced it's |
| 89 | * worth it... |
| 90 | */ |
| 91 | } else { |
| 92 | /* |
| 93 | * Main rlogin protocol. This is really simple: the first |
| 94 | * byte is expected to be NULL and is ignored, and the rest |
| 95 | * is printed. |
| 96 | */ |
| 97 | if (rlogin->firstbyte) { |
| 98 | if (data[0] == '\0') { |
| 99 | data++; |
| 100 | len--; |
| 101 | } |
| 102 | rlogin->firstbyte = 0; |
| 103 | } |
| 104 | if (len > 0) |
| 105 | c_write(rlogin, data, len); |
| 106 | } |
| 107 | return 1; |
| 108 | } |
| 109 | |
| 110 | static void rlogin_sent(Plug plug, int bufsize) |
| 111 | { |
| 112 | Rlogin rlogin = (Rlogin) plug; |
| 113 | rlogin->bufsize = bufsize; |
| 114 | } |
| 115 | |
| 116 | /* |
| 117 | * Called to set up the rlogin connection. |
| 118 | * |
| 119 | * Returns an error message, or NULL on success. |
| 120 | * |
| 121 | * Also places the canonical host name into `realhost'. It must be |
| 122 | * freed by the caller. |
| 123 | */ |
| 124 | static const char *rlogin_init(void *frontend_handle, void **backend_handle, |
| 125 | Config *cfg, |
| 126 | char *host, int port, char **realhost, |
| 127 | int nodelay, int keepalive) |
| 128 | { |
| 129 | static const struct plug_function_table fn_table = { |
| 130 | rlogin_log, |
| 131 | rlogin_closing, |
| 132 | rlogin_receive, |
| 133 | rlogin_sent |
| 134 | }; |
| 135 | SockAddr addr; |
| 136 | const char *err; |
| 137 | Rlogin rlogin; |
| 138 | |
| 139 | rlogin = snew(struct rlogin_tag); |
| 140 | rlogin->fn = &fn_table; |
| 141 | rlogin->s = NULL; |
| 142 | rlogin->frontend = frontend_handle; |
| 143 | rlogin->term_width = cfg->width; |
| 144 | rlogin->term_height = cfg->height; |
| 145 | rlogin->firstbyte = 1; |
| 146 | rlogin->cansize = 0; |
| 147 | *backend_handle = rlogin; |
| 148 | |
| 149 | /* |
| 150 | * Try to find host. |
| 151 | */ |
| 152 | { |
| 153 | char *buf; |
| 154 | buf = dupprintf("Looking up host \"%s\"%s", host, |
| 155 | (cfg->addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" : |
| 156 | (cfg->addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" : |
| 157 | ""))); |
| 158 | logevent(rlogin->frontend, buf); |
| 159 | sfree(buf); |
| 160 | } |
| 161 | addr = name_lookup(host, port, realhost, cfg, cfg->addressfamily); |
| 162 | if ((err = sk_addr_error(addr)) != NULL) { |
| 163 | sk_addr_free(addr); |
| 164 | return err; |
| 165 | } |
| 166 | |
| 167 | if (port < 0) |
| 168 | port = 513; /* default rlogin port */ |
| 169 | |
| 170 | /* |
| 171 | * Open socket. |
| 172 | */ |
| 173 | rlogin->s = new_connection(addr, *realhost, port, 1, 0, |
| 174 | nodelay, keepalive, (Plug) rlogin, cfg); |
| 175 | if ((err = sk_socket_error(rlogin->s)) != NULL) |
| 176 | return err; |
| 177 | |
| 178 | /* |
| 179 | * Send local username, remote username, terminal/speed |
| 180 | */ |
| 181 | |
| 182 | { |
| 183 | char z = 0; |
| 184 | char *p; |
| 185 | char ruser[sizeof(cfg->username)]; |
| 186 | (void) get_remote_username(cfg, ruser, sizeof(ruser)); |
| 187 | sk_write(rlogin->s, &z, 1); |
| 188 | sk_write(rlogin->s, cfg->localusername, |
| 189 | strlen(cfg->localusername)); |
| 190 | sk_write(rlogin->s, &z, 1); |
| 191 | sk_write(rlogin->s, ruser, |
| 192 | strlen(ruser)); |
| 193 | sk_write(rlogin->s, &z, 1); |
| 194 | sk_write(rlogin->s, cfg->termtype, |
| 195 | strlen(cfg->termtype)); |
| 196 | sk_write(rlogin->s, "/", 1); |
| 197 | for (p = cfg->termspeed; isdigit((unsigned char)*p); p++) continue; |
| 198 | sk_write(rlogin->s, cfg->termspeed, p - cfg->termspeed); |
| 199 | rlogin->bufsize = sk_write(rlogin->s, &z, 1); |
| 200 | } |
| 201 | |
| 202 | if (*cfg->loghost) { |
| 203 | char *colon; |
| 204 | |
| 205 | sfree(*realhost); |
| 206 | *realhost = dupstr(cfg->loghost); |
| 207 | colon = strrchr(*realhost, ':'); |
| 208 | if (colon) { |
| 209 | /* |
| 210 | * FIXME: if we ever update this aspect of ssh.c for |
| 211 | * IPv6 literal management, this should change in line |
| 212 | * with it. |
| 213 | */ |
| 214 | *colon++ = '\0'; |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | return NULL; |
| 219 | } |
| 220 | |
| 221 | static void rlogin_free(void *handle) |
| 222 | { |
| 223 | Rlogin rlogin = (Rlogin) handle; |
| 224 | |
| 225 | if (rlogin->s) |
| 226 | sk_close(rlogin->s); |
| 227 | sfree(rlogin); |
| 228 | } |
| 229 | |
| 230 | /* |
| 231 | * Stub routine (we don't have any need to reconfigure this backend). |
| 232 | */ |
| 233 | static void rlogin_reconfig(void *handle, Config *cfg) |
| 234 | { |
| 235 | } |
| 236 | |
| 237 | /* |
| 238 | * Called to send data down the rlogin connection. |
| 239 | */ |
| 240 | static int rlogin_send(void *handle, char *buf, int len) |
| 241 | { |
| 242 | Rlogin rlogin = (Rlogin) handle; |
| 243 | |
| 244 | if (rlogin->s == NULL) |
| 245 | return 0; |
| 246 | |
| 247 | rlogin->bufsize = sk_write(rlogin->s, buf, len); |
| 248 | |
| 249 | return rlogin->bufsize; |
| 250 | } |
| 251 | |
| 252 | /* |
| 253 | * Called to query the current socket sendability status. |
| 254 | */ |
| 255 | static int rlogin_sendbuffer(void *handle) |
| 256 | { |
| 257 | Rlogin rlogin = (Rlogin) handle; |
| 258 | return rlogin->bufsize; |
| 259 | } |
| 260 | |
| 261 | /* |
| 262 | * Called to set the size of the window |
| 263 | */ |
| 264 | static void rlogin_size(void *handle, int width, int height) |
| 265 | { |
| 266 | Rlogin rlogin = (Rlogin) handle; |
| 267 | char b[12] = { '\xFF', '\xFF', 0x73, 0x73, 0, 0, 0, 0, 0, 0, 0, 0 }; |
| 268 | |
| 269 | rlogin->term_width = width; |
| 270 | rlogin->term_height = height; |
| 271 | |
| 272 | if (rlogin->s == NULL || !rlogin->cansize) |
| 273 | return; |
| 274 | |
| 275 | b[6] = rlogin->term_width >> 8; |
| 276 | b[7] = rlogin->term_width & 0xFF; |
| 277 | b[4] = rlogin->term_height >> 8; |
| 278 | b[5] = rlogin->term_height & 0xFF; |
| 279 | rlogin->bufsize = sk_write(rlogin->s, b, 12); |
| 280 | return; |
| 281 | } |
| 282 | |
| 283 | /* |
| 284 | * Send rlogin special codes. |
| 285 | */ |
| 286 | static void rlogin_special(void *handle, Telnet_Special code) |
| 287 | { |
| 288 | /* Do nothing! */ |
| 289 | return; |
| 290 | } |
| 291 | |
| 292 | /* |
| 293 | * Return a list of the special codes that make sense in this |
| 294 | * protocol. |
| 295 | */ |
| 296 | static const struct telnet_special *rlogin_get_specials(void *handle) |
| 297 | { |
| 298 | return NULL; |
| 299 | } |
| 300 | |
| 301 | static int rlogin_connected(void *handle) |
| 302 | { |
| 303 | Rlogin rlogin = (Rlogin) handle; |
| 304 | return rlogin->s != NULL; |
| 305 | } |
| 306 | |
| 307 | static int rlogin_sendok(void *handle) |
| 308 | { |
| 309 | /* Rlogin rlogin = (Rlogin) handle; */ |
| 310 | return 1; |
| 311 | } |
| 312 | |
| 313 | static void rlogin_unthrottle(void *handle, int backlog) |
| 314 | { |
| 315 | Rlogin rlogin = (Rlogin) handle; |
| 316 | sk_set_frozen(rlogin->s, backlog > RLOGIN_MAX_BACKLOG); |
| 317 | } |
| 318 | |
| 319 | static int rlogin_ldisc(void *handle, int option) |
| 320 | { |
| 321 | /* Rlogin rlogin = (Rlogin) handle; */ |
| 322 | return 0; |
| 323 | } |
| 324 | |
| 325 | static void rlogin_provide_ldisc(void *handle, void *ldisc) |
| 326 | { |
| 327 | /* This is a stub. */ |
| 328 | } |
| 329 | |
| 330 | static void rlogin_provide_logctx(void *handle, void *logctx) |
| 331 | { |
| 332 | /* This is a stub. */ |
| 333 | } |
| 334 | |
| 335 | static int rlogin_exitcode(void *handle) |
| 336 | { |
| 337 | Rlogin rlogin = (Rlogin) handle; |
| 338 | if (rlogin->s != NULL) |
| 339 | return -1; /* still connected */ |
| 340 | else |
| 341 | /* If we ever implement RSH, we'll probably need to do this properly */ |
| 342 | return 0; |
| 343 | } |
| 344 | |
| 345 | /* |
| 346 | * cfg_info for rlogin does nothing at all. |
| 347 | */ |
| 348 | static int rlogin_cfg_info(void *handle) |
| 349 | { |
| 350 | return 0; |
| 351 | } |
| 352 | |
| 353 | Backend rlogin_backend = { |
| 354 | rlogin_init, |
| 355 | rlogin_free, |
| 356 | rlogin_reconfig, |
| 357 | rlogin_send, |
| 358 | rlogin_sendbuffer, |
| 359 | rlogin_size, |
| 360 | rlogin_special, |
| 361 | rlogin_get_specials, |
| 362 | rlogin_connected, |
| 363 | rlogin_exitcode, |
| 364 | rlogin_sendok, |
| 365 | rlogin_ldisc, |
| 366 | rlogin_provide_ldisc, |
| 367 | rlogin_provide_logctx, |
| 368 | rlogin_unthrottle, |
| 369 | rlogin_cfg_info, |
| 370 | "rlogin", |
| 371 | PROT_RLOGIN, |
| 372 | 513 |
| 373 | }; |