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

   1 #include <windows.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #ifndef AUTO_WINSOCK
   5 #ifdef WINSOCK_TWO
   6 #include <winsock2.h>
   7 #else
   8 #include <winsock.h>
   9 #endif
  10 #endif
  11
  12 #include "putty.h"
  13
  14 #ifndef FALSE
  15 #define FALSE 0
  16 #endif
  17 #ifndef TRUE
  18 #define TRUE 1
  19 #endif
  20
  21 static SOCKET s = INVALID_SOCKET;
  22
  23 static void raw_size(void);
  24
  25 static int sb_opt, sb_len;
  26 static char *sb_buf = NULL;
  27 static int sb_size = 0;
  28 #define SB_DELTA 1024
  29
  30 static void try_write (void) {
  31     while (outbuf_head != outbuf_reap) {
  32         int end = (outbuf_reap < outbuf_head ? outbuf_head : OUTBUF_SIZE);
  33         int len = end - outbuf_reap;
  34         int ret;
  35
  36         ret = send (s, outbuf+outbuf_reap, len, 0);
  37         if (ret > 0)
  38             outbuf_reap = (outbuf_reap + ret) & OUTBUF_MASK;
  39         if (ret < len)
  40             return;
  41     }
  42 }
  43
  44 static void s_write (void *buf, int len) {
  45     unsigned char *p = buf;
  46     while (len--) {
  47         int new_head = (outbuf_head + 1) & OUTBUF_MASK;
  48         if (new_head != outbuf_reap) {
  49             outbuf[outbuf_head] = *p++;
  50             outbuf_head = new_head;
  51         }
  52     }
  53     try_write();
  54 }
  55
  56 static void c_write (char *buf, int len) {
  57     while (len--)
  58         c_write1(*buf++);
  59 }
  60
  61 /*
  62  * Called to set up the raw connection. Will arrange for
  63  * WM_NETEVENT messages to be passed to the specified window, whose
  64  * window procedure should then call raw_msg().
  65  *
  66  * Returns an error message, or NULL on success.
  67  *
  68  * Also places the canonical host name into `realhost'.
  69  */
  70 static char *raw_init (HWND hwnd, char *host, int port, char **realhost) {
  71     SOCKADDR_IN addr;
  72     struct hostent *h;
  73     unsigned long a;
  74
  75     /*
  76      * Try to find host.
  77      */
  78     if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
  79         if ( (h = gethostbyname(host)) == NULL)
  80             switch (WSAGetLastError()) {
  81               case WSAENETDOWN: return "Network is down";
  82               case WSAHOST_NOT_FOUND: case WSANO_DATA:
  83                 return "Host does not exist";
  84               case WSATRY_AGAIN: return "Host not found";
  85               default: return "gethostbyname: unknown error";
  86             }
  87         memcpy (&a, h->h_addr, sizeof(a));
  88         *realhost = h->h_name;
  89     } else
  90         *realhost = host;
  91     a = ntohl(a);
  92
  93     if (port < 0)
  94         port = 23;                     /* default telnet port */
  95
  96     /*
  97      * Open socket.
  98      */
  99     s = socket(AF_INET, SOCK_STREAM, 0);
 100     if (s == INVALID_SOCKET)
 101         switch (WSAGetLastError()) {
 102           case WSAENETDOWN: return "Network is down";
 103           case WSAEAFNOSUPPORT: return "TCP/IP support not present";
 104           default: return "socket(): unknown error";
 105         }
 106
 107     /*
 108      * Bind to local address.
 109      */
 110     addr.sin_family = AF_INET;
 111     addr.sin_addr.s_addr = htonl(INADDR_ANY);
 112     addr.sin_port = htons(0);
 113     if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
 114         switch (WSAGetLastError()) {
 115           case WSAENETDOWN: return "Network is down";
 116           default: return "bind(): unknown error";
 117         }
 118
 119     /*
 120      * Connect to remote address.
 121      */
 122     addr.sin_addr.s_addr = htonl(a);
 123     addr.sin_port = htons((short)port);
 124     if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
 125         switch (WSAGetLastError()) {
 126           case WSAENETDOWN: return "Network is down";
 127           case WSAECONNREFUSED: return "Connection refused";
 128           case WSAENETUNREACH: return "Network is unreachable";
 129           case WSAEHOSTUNREACH: return "No route to host";
 130           default: return "connect(): unknown error";
 131         }
 132
 133     if (hwnd && WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ |
 134                         FD_WRITE | FD_OOB | FD_CLOSE) == SOCKET_ERROR)
 135         switch (WSAGetLastError()) {
 136           case WSAENETDOWN: return "Network is down";
 137           default: return "WSAAsyncSelect(): unknown error";
 138         }
 139
 140     /*
 141      * We have no pre-session phase.
 142      */
 143     begin_session();
 144
 145     return NULL;
 146 }
 147
 148 /*
 149  * Process a WM_NETEVENT message. Will return 0 if the connection
 150  * has closed, or <0 for a socket error.
 151  */
 152 static int raw_msg (WPARAM wParam, LPARAM lParam) {
 153     int ret;
 154     char buf[256];
 155
 156     /*
 157      * Because reading less than the whole of the available pending
 158      * data can generate an FD_READ event, we need to allow for the
 159      * possibility that FD_READ may arrive with FD_CLOSE already in
 160      * the queue; so it's possible that we can get here even with s
 161      * invalid. If so, we return 1 and don't worry about it.
 162      */
 163     if (s == INVALID_SOCKET) {
 164         closesocket(s);
 165         s = INVALID_SOCKET;
 166         return 1;
 167     }
 168
 169     if (WSAGETSELECTERROR(lParam) != 0)
 170         return -WSAGETSELECTERROR(lParam);
 171
 172     switch (WSAGETSELECTEVENT(lParam)) {
 173       case FD_READ:
 174       case FD_CLOSE:
 175         ret = recv(s, buf, sizeof(buf), 0);
 176         if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
 177             return 1;
 178         if (ret < 0) {                 /* any _other_ error */
 179             closesocket(s);
 180             s = INVALID_SOCKET;
 181             return -10000-WSAGetLastError();
 182         }
 183         if (ret == 0) {
 184             s = INVALID_SOCKET;
 185             return 0;
 186         }
 187         c_write( buf, ret );
 188         return 1;
 189       case FD_OOB:
 190         do {
 191             ret = recv(s, buf, sizeof(buf), 0);
 192             c_write( buf, ret );
 193         } while (ret > 0);
 194         do {
 195             ret = recv(s, buf, 1, MSG_OOB);
 196         } while (ret > 0);
 197         if (ret < 0 && WSAGetLastError() != WSAEWOULDBLOCK)
 198             return -30000-WSAGetLastError();
 199         return 1;
 200       case FD_WRITE:
 201         if (outbuf_head != outbuf_reap)
 202             try_write();
 203         return 1;
 204     }
 205     return 1;                          /* shouldn't happen, but WTF */
 206 }
 207
 208 /*
 209  * Called to send data down the raw connection.
 210  */
 211 static void raw_send (char *buf, int len) {
 212
 213     if (s == INVALID_SOCKET)
 214         return;
 215
 216     s_write( buf, len );
 217 }
 218
 219 /*
 220  * Called to set the size of the window
 221  */
 222 static void raw_size(void) {
 223     /* Do nothing! */
 224     return;
 225 }
 226
 227 /*
 228  * Send raw special codes.
 229  */
 230 static void raw_special (Telnet_Special code) {
 231     /* Do nothing! */
 232     return;
 233 }
 234
 235 static SOCKET raw_socket(void) { return s; }
 236
 237 static int raw_sendok(void) { return 1; }
 238
 239 Backend raw_backend = {
 240     raw_init,
 241     raw_msg,
 242     raw_send,
 243     raw_size,
 244     raw_special,
 245     raw_socket,
 246     raw_sendok
 247 };