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

   1 #include <windows.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <winsock.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 static SOCKET s = INVALID_SOCKET;
  16
  17 static void raw_size(void);
  18
  19 static int sb_opt, sb_len;
  20 static char *sb_buf = NULL;
  21 static int sb_size = 0;
  22 #define SB_DELTA 1024
  23
  24 static void try_write (void) {
  25     while (outbuf_head != outbuf_reap) {
  26         int end = (outbuf_reap < outbuf_head ? outbuf_head : OUTBUF_SIZE);
  27         int len = end - outbuf_reap;
  28         int ret;
  29
  30         ret = send (s, outbuf+outbuf_reap, len, 0);
  31         if (ret > 0)
  32             outbuf_reap = (outbuf_reap + ret) & OUTBUF_MASK;
  33         if (ret < len)
  34             return;
  35     }
  36 }
  37
  38 static void s_write (void *buf, int len) {
  39     unsigned char *p = buf;
  40     while (len--) {
  41         int new_head = (outbuf_head + 1) & OUTBUF_MASK;
  42         if (new_head != outbuf_reap) {
  43             outbuf[outbuf_head] = *p++;
  44             outbuf_head = new_head;
  45         }
  46     }
  47     try_write();
  48 }
  49
  50 static void c_write (char *buf, int len) {
  51     while (len--)
  52         c_write1(*buf++);
  53 }
  54
  55 /*
  56  * Called to set up the raw connection. Will arrange for
  57  * WM_NETEVENT messages to be passed to the specified window, whose
  58  * window procedure should then call raw_msg().
  59  *
  60  * Returns an error message, or NULL on success.
  61  *
  62  * Also places the canonical host name into `realhost'.
  63  */
  64 static char *raw_init (HWND hwnd, char *host, int port, char **realhost) {
  65     SOCKADDR_IN addr;
  66     struct hostent *h;
  67     unsigned long a;
  68
  69     /*
  70      * Try to find host.
  71      */
  72     if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
  73         if ( (h = gethostbyname(host)) == NULL)
  74             switch (WSAGetLastError()) {
  75               case WSAENETDOWN: return "Network is down";
  76               case WSAHOST_NOT_FOUND: case WSANO_DATA:
  77                 return "Host does not exist";
  78               case WSATRY_AGAIN: return "Host not found";
  79               default: return "gethostbyname: unknown error";
  80             }
  81         memcpy (&a, h->h_addr, sizeof(a));
  82         *realhost = h->h_name;
  83     } else
  84         *realhost = host;
  85     a = ntohl(a);
  86
  87     if (port < 0)
  88         port = 23;                     /* default telnet port */
  89
  90     /*
  91      * Open socket.
  92      */
  93     s = socket(AF_INET, SOCK_STREAM, 0);
  94     if (s == INVALID_SOCKET)
  95         switch (WSAGetLastError()) {
  96           case WSAENETDOWN: return "Network is down";
  97           case WSAEAFNOSUPPORT: return "TCP/IP support not present";
  98           default: return "socket(): unknown error";
  99         }
 100
 101     /*
 102      * Bind to local address.
 103      */
 104     addr.sin_family = AF_INET;
 105     addr.sin_addr.s_addr = htonl(INADDR_ANY);
 106     addr.sin_port = htons(0);
 107     if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
 108         switch (WSAGetLastError()) {
 109           case WSAENETDOWN: return "Network is down";
 110           default: return "bind(): unknown error";
 111         }
 112
 113     /*
 114      * Connect to remote address.
 115      */
 116     addr.sin_addr.s_addr = htonl(a);
 117     addr.sin_port = htons((short)port);
 118     if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
 119         switch (WSAGetLastError()) {
 120           case WSAENETDOWN: return "Network is down";
 121           case WSAECONNREFUSED: return "Connection refused";
 122           case WSAENETUNREACH: return "Network is unreachable";
 123           case WSAEHOSTUNREACH: return "No route to host";
 124           default: return "connect(): unknown error";
 125         }
 126
 127     if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ |
 128                         FD_WRITE | FD_OOB | FD_CLOSE) == SOCKET_ERROR)
 129         switch (WSAGetLastError()) {
 130           case WSAENETDOWN: return "Network is down";
 131           default: return "WSAAsyncSelect(): unknown error";
 132         }
 133
 134     return NULL;
 135 }
 136
 137 /*
 138  * Process a WM_NETEVENT message. Will return 0 if the connection
 139  * has closed, or <0 for a socket error.
 140  */
 141 static int raw_msg (WPARAM wParam, LPARAM lParam) {
 142     int ret;
 143     char buf[256];
 144
 145     /*
 146      * Because reading less than the whole of the available pending
 147      * data can generate an FD_READ event, we need to allow for the
 148      * possibility that FD_READ may arrive with FD_CLOSE already in
 149      * the queue; so it's possible that we can get here even with s
 150      * invalid. If so, we return 1 and don't worry about it.
 151      */
 152     if (s == INVALID_SOCKET)
 153         return 1;
 154
 155     if (WSAGETSELECTERROR(lParam) != 0)
 156         return -WSAGETSELECTERROR(lParam);
 157
 158     switch (WSAGETSELECTEVENT(lParam)) {
 159       case FD_READ:
 160       case FD_CLOSE:
 161         ret = recv(s, buf, sizeof(buf), 0);
 162         if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
 163             return 1;
 164         if (ret < 0)                   /* any _other_ error */
 165             return -10000-WSAGetLastError();
 166         if (ret == 0) {
 167             s = INVALID_SOCKET;
 168             return 0;
 169         }
 170         c_write( buf, ret );
 171         return 1;
 172       case FD_OOB:
 173         do {
 174             ret = recv(s, buf, sizeof(buf), 0);
 175             c_write( buf, ret );
 176         } while (ret > 0);
 177         do {
 178             ret = recv(s, buf, 1, MSG_OOB);
 179         } while (ret > 0);
 180         if (ret < 0 && WSAGetLastError() != WSAEWOULDBLOCK)
 181             return -30000-WSAGetLastError();
 182         return 1;
 183       case FD_WRITE:
 184         if (outbuf_head != outbuf_reap)
 185             try_write();
 186         return 1;
 187     }
 188     return 1;                          /* shouldn't happen, but WTF */
 189 }
 190
 191 /*
 192  * Called to send data down the raw connection.
 193  */
 194 static void raw_send (char *buf, int len) {
 195
 196     if (s == INVALID_SOCKET)
 197         return;
 198
 199     s_write( buf, len );
 200 }
 201
 202 /*
 203  * Called to set the size of the window
 204  */
 205 static void raw_size(void) {
 206     /* Do nothing! */
 207     return;
 208 }
 209
 210 /*
 211  * Send raw special codes.
 212  */
 213 static void raw_special (Telnet_Special code) {
 214     /* Do nothing! */
 215     return;
 216 }
 217
 218 SOCKET raw_socket(void) { return s; }
 219
 220 Backend raw_backend = {
 221     raw_init,
 222     raw_msg,
 223     raw_send,
 224     raw_size,
 225     raw_special,
 226     raw_socket
 227 };