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

   1 /*
   2  * "Raw" backend.
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7
   8 #include "putty.h"
   9
  10 #ifndef FALSE
  11 #define FALSE 0
  12 #endif
  13 #ifndef TRUE
  14 #define TRUE 1
  15 #endif
  16
  17 #define RAW_MAX_BACKLOG 4096
  18
  19 typedef struct raw_backend_data {
  20     const struct plug_function_table *fn;
  21     /* the above field _must_ be first in the structure */
  22
  23     Socket s;
  24     int bufsize;
  25     void *frontend;
  26 } *Raw;
  27
  28 static void raw_size(void *handle, int width, int height);
  29
  30 static void c_write(Raw raw, char *buf, int len)
  31 {
  32     int backlog = from_backend(raw->frontend, 0, buf, len);
  33     sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
  34 }
  35
  36 static void raw_log(Plug plug, int type, SockAddr addr, int port,
  37                     const char *error_msg, int error_code)
  38 {
  39     Raw raw = (Raw) plug;
  40     char addrbuf[256], *msg;
  41
  42     sk_getaddr(addr, addrbuf, lenof(addrbuf));
  43
  44     if (type == 0)
  45         msg = dupprintf("Connecting to %s port %d", addrbuf, port);
  46     else
  47         msg = dupprintf("Failed to connect to %s: %s", addrbuf, error_msg);
  48
  49     logevent(raw->frontend, msg);
  50 }
  51
  52 static int raw_closing(Plug plug, const char *error_msg, int error_code,
  53                        int calling_back)
  54 {
  55     Raw raw = (Raw) plug;
  56
  57     if (raw->s) {
  58         sk_close(raw->s);
  59         raw->s = NULL;
  60         notify_remote_exit(raw->frontend);
  61     }
  62     if (error_msg) {
  63         /* A socket error has occurred. */
  64         logevent(raw->frontend, error_msg);
  65         connection_fatal(raw->frontend, "%s", error_msg);
  66     }                                  /* Otherwise, the remote side closed the connection normally. */
  67     return 0;
  68 }
  69
  70 static int raw_receive(Plug plug, int urgent, char *data, int len)
  71 {
  72     Raw raw = (Raw) plug;
  73     c_write(raw, data, len);
  74     return 1;
  75 }
  76
  77 static void raw_sent(Plug plug, int bufsize)
  78 {
  79     Raw raw = (Raw) plug;
  80     raw->bufsize = bufsize;
  81 }
  82
  83 /*
  84  * Called to set up the raw 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 const char *raw_init(void *frontend_handle, void **backend_handle,
  92                             Conf *conf,
  93                             char *host, int port, char **realhost, int nodelay,
  94                             int keepalive)
  95 {
  96     static const struct plug_function_table fn_table = {
  97         raw_log,
  98         raw_closing,
  99         raw_receive,
 100         raw_sent
 101     };
 102     SockAddr addr;
 103     const char *err;
 104     Raw raw;
 105     int addressfamily;
 106     char *loghost;
 107
 108     raw = snew(struct raw_backend_data);
 109     raw->fn = &fn_table;
 110     raw->s = NULL;
 111     *backend_handle = raw;
 112
 113     raw->frontend = frontend_handle;
 114
 115     addressfamily = conf_get_int(conf, CONF_addressfamily);
 116     /*
 117      * Try to find host.
 118      */
 119     {
 120         char *buf;
 121         buf = dupprintf("Looking up host \"%s\"%s", host,
 122                         (addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
 123                          (addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" :
 124                           "")));
 125         logevent(raw->frontend, buf);
 126         sfree(buf);
 127     }
 128     addr = name_lookup(host, port, realhost, conf, addressfamily);
 129     if ((err = sk_addr_error(addr)) != NULL) {
 130         sk_addr_free(addr);
 131         return err;
 132     }
 133
 134     if (port < 0)
 135         port = 23;                     /* default telnet port */
 136
 137     /*
 138      * Open socket.
 139      */
 140     raw->s = new_connection(addr, *realhost, port, 0, 1, nodelay, keepalive,
 141                             (Plug) raw, conf);
 142     if ((err = sk_socket_error(raw->s)) != NULL)
 143         return err;
 144
 145     loghost = conf_get_str(conf, CONF_loghost);
 146     if (*loghost) {
 147         char *colon;
 148
 149         sfree(*realhost);
 150         *realhost = dupstr(loghost);
 151         colon = strrchr(*realhost, ':');
 152         if (colon) {
 153             /*
 154              * FIXME: if we ever update this aspect of ssh.c for
 155              * IPv6 literal management, this should change in line
 156              * with it.
 157              */
 158             *colon++ = '\0';
 159         }
 160     }
 161
 162     return NULL;
 163 }
 164
 165 static void raw_free(void *handle)
 166 {
 167     Raw raw = (Raw) handle;
 168
 169     if (raw->s)
 170         sk_close(raw->s);
 171     sfree(raw);
 172 }
 173
 174 /*
 175  * Stub routine (we don't have any need to reconfigure this backend).
 176  */
 177 static void raw_reconfig(void *handle, Conf *conf)
 178 {
 179 }
 180
 181 /*
 182  * Called to send data down the raw connection.
 183  */
 184 static int raw_send(void *handle, char *buf, int len)
 185 {
 186     Raw raw = (Raw) handle;
 187
 188     if (raw->s == NULL)
 189         return 0;
 190
 191     raw->bufsize = sk_write(raw->s, buf, len);
 192
 193     return raw->bufsize;
 194 }
 195
 196 /*
 197  * Called to query the current socket sendability status.
 198  */
 199 static int raw_sendbuffer(void *handle)
 200 {
 201     Raw raw = (Raw) handle;
 202     return raw->bufsize;
 203 }
 204
 205 /*
 206  * Called to set the size of the window
 207  */
 208 static void raw_size(void *handle, int width, int height)
 209 {
 210     /* Do nothing! */
 211     return;
 212 }
 213
 214 /*
 215  * Send raw special codes.
 216  */
 217 static void raw_special(void *handle, Telnet_Special code)
 218 {
 219     /* Do nothing! */
 220     return;
 221 }
 222
 223 /*
 224  * Return a list of the special codes that make sense in this
 225  * protocol.
 226  */
 227 static const struct telnet_special *raw_get_specials(void *handle)
 228 {
 229     return NULL;
 230 }
 231
 232 static int raw_connected(void *handle)
 233 {
 234     Raw raw = (Raw) handle;
 235     return raw->s != NULL;
 236 }
 237
 238 static int raw_sendok(void *handle)
 239 {
 240     return 1;
 241 }
 242
 243 static void raw_unthrottle(void *handle, int backlog)
 244 {
 245     Raw raw = (Raw) handle;
 246     sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
 247 }
 248
 249 static int raw_ldisc(void *handle, int option)
 250 {
 251     if (option == LD_EDIT || option == LD_ECHO)
 252         return 1;
 253     return 0;
 254 }
 255
 256 static void raw_provide_ldisc(void *handle, void *ldisc)
 257 {
 258     /* This is a stub. */
 259 }
 260
 261 static void raw_provide_logctx(void *handle, void *logctx)
 262 {
 263     /* This is a stub. */
 264 }
 265
 266 static int raw_exitcode(void *handle)
 267 {
 268     Raw raw = (Raw) handle;
 269     if (raw->s != NULL)
 270         return -1;                     /* still connected */
 271     else
 272         /* Exit codes are a meaningless concept in the Raw protocol */
 273         return 0;
 274 }
 275
 276 /*
 277  * cfg_info for Raw does nothing at all.
 278  */
 279 static int raw_cfg_info(void *handle)
 280 {
 281     return 0;
 282 }
 283
 284 Backend raw_backend = {
 285     raw_init,
 286     raw_free,
 287     raw_reconfig,
 288     raw_send,
 289     raw_sendbuffer,
 290     raw_size,
 291     raw_special,
 292     raw_get_specials,
 293     raw_connected,
 294     raw_exitcode,
 295     raw_sendok,
 296     raw_ldisc,
 297     raw_provide_ldisc,
 298     raw_provide_logctx,
 299     raw_unthrottle,
 300     raw_cfg_info,
 301     "raw",
 302     PROT_RAW,
 303     0
 304 };