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

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3
   4 #include "putty.h"
   5
   6 #ifndef FALSE
   7 #define FALSE 0
   8 #endif
   9 #ifndef TRUE
  10 #define TRUE 1
  11 #endif
  12
  13 #define RAW_MAX_BACKLOG 4096
  14
  15 typedef struct raw_backend_data {
  16     const struct plug_function_table *fn;
  17     /* the above field _must_ be first in the structure */
  18
  19     Socket s;
  20     int bufsize;
  21     void *frontend;
  22 } *Raw;
  23
  24 static void raw_size(void *handle, int width, int height);
  25
  26 static void c_write(Raw raw, char *buf, int len)
  27 {
  28     int backlog = from_backend(raw->frontend, 0, buf, len);
  29     sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
  30 }
  31
  32 static int raw_closing(Plug plug, const char *error_msg, int error_code,
  33                        int calling_back)
  34 {
  35     Raw raw = (Raw) plug;
  36
  37     if (raw->s) {
  38         sk_close(raw->s);
  39         raw->s = NULL;
  40         notify_remote_exit(raw->frontend);
  41     }
  42     if (error_msg) {
  43         /* A socket error has occurred. */
  44         logevent(raw->frontend, error_msg);
  45         connection_fatal(raw->frontend, "%s", error_msg);
  46     }                                  /* Otherwise, the remote side closed the connection normally. */
  47     return 0;
  48 }
  49
  50 static int raw_receive(Plug plug, int urgent, char *data, int len)
  51 {
  52     Raw raw = (Raw) plug;
  53     c_write(raw, data, len);
  54     return 1;
  55 }
  56
  57 static void raw_sent(Plug plug, int bufsize)
  58 {
  59     Raw raw = (Raw) plug;
  60     raw->bufsize = bufsize;
  61 }
  62
  63 /*
  64  * Called to set up the raw connection.
  65  *
  66  * Returns an error message, or NULL on success.
  67  *
  68  * Also places the canonical host name into `realhost'. It must be
  69  * freed by the caller.
  70  */
  71 static const char *raw_init(void *frontend_handle, void **backend_handle,
  72                             Config *cfg,
  73                             char *host, int port, char **realhost, int nodelay,
  74                             int keepalive)
  75 {
  76     static const struct plug_function_table fn_table = {
  77         raw_closing,
  78         raw_receive,
  79         raw_sent
  80     };
  81     SockAddr addr;
  82     const char *err;
  83     Raw raw;
  84
  85     raw = snew(struct raw_backend_data);
  86     raw->fn = &fn_table;
  87     raw->s = NULL;
  88     *backend_handle = raw;
  89
  90     raw->frontend = frontend_handle;
  91
  92     /*
  93      * Try to find host.
  94      */
  95     {
  96         char *buf;
  97         buf = dupprintf("Looking up host \"%s\"%s", host,
  98                         (cfg->addressfamily == ADDRTYPE_IPV4 ? " (IPv4)" :
  99                          (cfg->addressfamily == ADDRTYPE_IPV6 ? " (IPv6)" :
 100                           "")));
 101         logevent(raw->frontend, buf);
 102         sfree(buf);
 103     }
 104     addr = name_lookup(host, port, realhost, cfg, cfg->addressfamily);
 105     if ((err = sk_addr_error(addr)) != NULL) {
 106         sk_addr_free(addr);
 107         return err;
 108     }
 109
 110     if (port < 0)
 111         port = 23;                     /* default telnet port */
 112
 113     /*
 114      * Open socket.
 115      */
 116     {
 117         char *buf, addrbuf[100];
 118         sk_getaddr(addr, addrbuf, 100);
 119         buf = dupprintf("Connecting to %s port %d", addrbuf, port);
 120         logevent(raw->frontend, buf);
 121         sfree(buf);
 122     }
 123     raw->s = new_connection(addr, *realhost, port, 0, 1, nodelay, keepalive,
 124                             (Plug) raw, cfg);
 125     if ((err = sk_socket_error(raw->s)) != NULL)
 126         return err;
 127
 128     return NULL;
 129 }
 130
 131 static void raw_free(void *handle)
 132 {
 133     Raw raw = (Raw) handle;
 134
 135     if (raw->s)
 136         sk_close(raw->s);
 137     sfree(raw);
 138 }
 139
 140 /*
 141  * Stub routine (we don't have any need to reconfigure this backend).
 142  */
 143 static void raw_reconfig(void *handle, Config *cfg)
 144 {
 145 }
 146
 147 /*
 148  * Called to send data down the raw connection.
 149  */
 150 static int raw_send(void *handle, char *buf, int len)
 151 {
 152     Raw raw = (Raw) handle;
 153
 154     if (raw->s == NULL)
 155         return 0;
 156
 157     raw->bufsize = sk_write(raw->s, buf, len);
 158
 159     return raw->bufsize;
 160 }
 161
 162 /*
 163  * Called to query the current socket sendability status.
 164  */
 165 static int raw_sendbuffer(void *handle)
 166 {
 167     Raw raw = (Raw) handle;
 168     return raw->bufsize;
 169 }
 170
 171 /*
 172  * Called to set the size of the window
 173  */
 174 static void raw_size(void *handle, int width, int height)
 175 {
 176     /* Do nothing! */
 177     return;
 178 }
 179
 180 /*
 181  * Send raw special codes.
 182  */
 183 static void raw_special(void *handle, Telnet_Special code)
 184 {
 185     /* Do nothing! */
 186     return;
 187 }
 188
 189 /*
 190  * Return a list of the special codes that make sense in this
 191  * protocol.
 192  */
 193 static const struct telnet_special *raw_get_specials(void *handle)
 194 {
 195     return NULL;
 196 }
 197
 198 static Socket raw_socket(void *handle)
 199 {
 200     Raw raw = (Raw) handle;
 201     return raw->s;
 202 }
 203
 204 static int raw_sendok(void *handle)
 205 {
 206     return 1;
 207 }
 208
 209 static void raw_unthrottle(void *handle, int backlog)
 210 {
 211     Raw raw = (Raw) handle;
 212     sk_set_frozen(raw->s, backlog > RAW_MAX_BACKLOG);
 213 }
 214
 215 static int raw_ldisc(void *handle, int option)
 216 {
 217     if (option == LD_EDIT || option == LD_ECHO)
 218         return 1;
 219     return 0;
 220 }
 221
 222 static void raw_provide_ldisc(void *handle, void *ldisc)
 223 {
 224     /* This is a stub. */
 225 }
 226
 227 static void raw_provide_logctx(void *handle, void *logctx)
 228 {
 229     /* This is a stub. */
 230 }
 231
 232 static int raw_exitcode(void *handle)
 233 {
 234     Raw raw = (Raw) handle;
 235     if (raw->s != NULL)
 236         return -1;                     /* still connected */
 237     else
 238         /* Exit codes are a meaningless concept in the Raw protocol */
 239         return 0;
 240 }
 241
 242 /*
 243  * cfg_info for Raw does nothing at all.
 244  */
 245 static int raw_cfg_info(void *handle)
 246 {
 247     return 0;
 248 }
 249
 250 Backend raw_backend = {
 251     raw_init,
 252     raw_free,
 253     raw_reconfig,
 254     raw_send,
 255     raw_sendbuffer,
 256     raw_size,
 257     raw_special,
 258     raw_get_specials,
 259     raw_socket,
 260     raw_exitcode,
 261     raw_sendok,
 262     raw_ldisc,
 263     raw_provide_ldisc,
 264     raw_provide_logctx,
 265     raw_unthrottle,
 266     raw_cfg_info,
 267     1
 268 };