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 #define iswritable(x) ( (x) != IAC && (x) != CR )
  18
  19 static void raw_size(void);
  20
  21 static int sb_opt, sb_len;
  22 static char *sb_buf = NULL;
  23 static int sb_size = 0;
  24 #define SB_DELTA 1024
  25
  26 static void try_write (void) {
  27     while (outbuf_head != outbuf_reap) {
  28         int end = (outbuf_reap < outbuf_head ? outbuf_head : OUTBUF_SIZE);
  29         int len = end - outbuf_reap;
  30         int ret;
  31
  32         ret = send (s, outbuf+outbuf_reap, len, 0);
  33         if (ret > 0)
  34             outbuf_reap = (outbuf_reap + ret) & OUTBUF_MASK;
  35         if (ret < len)
  36             return;
  37     }
  38 }
  39
  40 static void s_write (void *buf, int len) {
  41     unsigned char *p = buf;
  42     while (len--) {
  43         int new_head = (outbuf_head + 1) & OUTBUF_MASK;
  44         if (new_head != outbuf_reap) {
  45             outbuf[outbuf_head] = *p++;
  46             outbuf_head = new_head;
  47         }
  48     }
  49     try_write();
  50 }
  51
  52 static void c_write (char *buf, int len) {
  53     while (len--) {
  54         int new_head = (inbuf_head + 1) & INBUF_MASK;
  55         int c = (unsigned char) *buf;
  56         if (new_head != inbuf_reap) {
  57             inbuf[inbuf_head] = *buf++;
  58             inbuf_head = new_head;
  59         } else {
  60             term_out();
  61             if( inbuf_head == inbuf_reap ) len++; else break;
  62         }
  63     }
  64 }
  65
  66 /*
  67  * Called to set up the raw connection. Will arrange for
  68  * WM_NETEVENT messages to be passed to the specified window, whose
  69  * window procedure should then call raw_msg().
  70  *
  71  * Returns an error message, or NULL on success.
  72  *
  73  * Also places the canonical host name into `realhost'.
  74  */
  75 static char *raw_init (HWND hwnd, char *host, int port, char **realhost) {
  76     SOCKADDR_IN addr;
  77     struct hostent *h;
  78     unsigned long a;
  79
  80     /*
  81      * Try to find host.
  82      */
  83     if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
  84         if ( (h = gethostbyname(host)) == NULL)
  85             switch (WSAGetLastError()) {
  86               case WSAENETDOWN: return "Network is down";
  87               case WSAHOST_NOT_FOUND: case WSANO_DATA:
  88                 return "Host does not exist";
  89               case WSATRY_AGAIN: return "Host not found";
  90               default: return "gethostbyname: unknown error";
  91             }
  92         memcpy (&a, h->h_addr, sizeof(a));
  93         *realhost = h->h_name;
  94     } else
  95         *realhost = host;
  96     a = ntohl(a);
  97
  98     if (port < 0)
  99         port = 23;                     /* default telnet port */
 100
 101     /*
 102      * Open socket.
 103      */
 104     s = socket(AF_INET, SOCK_STREAM, 0);
 105     if (s == INVALID_SOCKET)
 106         switch (WSAGetLastError()) {
 107           case WSAENETDOWN: return "Network is down";
 108           case WSAEAFNOSUPPORT: return "TCP/IP support not present";
 109           default: return "socket(): unknown error";
 110         }
 111
 112     /*
 113      * Bind to local address.
 114      */
 115     addr.sin_family = AF_INET;
 116     addr.sin_addr.s_addr = htonl(INADDR_ANY);
 117     addr.sin_port = htons(0);
 118     if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
 119         switch (WSAGetLastError()) {
 120           case WSAENETDOWN: return "Network is down";
 121           default: return "bind(): unknown error";
 122         }
 123
 124     /*
 125      * Connect to remote address.
 126      */
 127     addr.sin_addr.s_addr = htonl(a);
 128     addr.sin_port = htons((short)port);
 129     if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
 130         switch (WSAGetLastError()) {
 131           case WSAENETDOWN: return "Network is down";
 132           case WSAECONNREFUSED: return "Connection refused";
 133           case WSAENETUNREACH: return "Network is unreachable";
 134           case WSAEHOSTUNREACH: return "No route to host";
 135           default: return "connect(): unknown error";
 136         }
 137
 138     if (WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ |
 139                         FD_WRITE | FD_OOB | FD_CLOSE) == SOCKET_ERROR)
 140         switch (WSAGetLastError()) {
 141           case WSAENETDOWN: return "Network is down";
 142           default: return "WSAAsyncSelect(): unknown error";
 143         }
 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         return 1;
 165
 166     if (WSAGETSELECTERROR(lParam) != 0)
 167         return -WSAGETSELECTERROR(lParam);
 168
 169     switch (WSAGETSELECTEVENT(lParam)) {
 170       case FD_READ:
 171       case FD_CLOSE:
 172         ret = recv(s, buf, sizeof(buf), 0);
 173         if (ret < 0 && WSAGetLastError() == WSAEWOULDBLOCK)
 174             return 1;
 175         if (ret < 0)                   /* any _other_ error */
 176             return -10000-WSAGetLastError();
 177         if (ret == 0) {
 178             s = INVALID_SOCKET;
 179             return 0;
 180         }
 181         c_write( buf, ret );
 182         return 1;
 183       case FD_OOB:
 184         do {
 185             ret = recv(s, buf, sizeof(buf), 0);
 186             c_write( buf, ret );
 187         } while (ret > 0);
 188         do {
 189             ret = recv(s, buf, 1, MSG_OOB);
 190         } while (ret > 0);
 191         if (ret < 0 && WSAGetLastError() != WSAEWOULDBLOCK)
 192             return -30000-WSAGetLastError();
 193         return 1;
 194       case FD_WRITE:
 195         if (outbuf_head != outbuf_reap)
 196             try_write();
 197         return 1;
 198     }
 199     return 1;                          /* shouldn't happen, but WTF */
 200 }
 201
 202 /*
 203  * Called to send data down the raw connection.
 204  */
 205 static void raw_send (char *buf, int len) {
 206
 207     if (s == INVALID_SOCKET)
 208         return;
 209
 210     s_write( buf, len );
 211 }
 212
 213 /*
 214  * Called to set the size of the window
 215  */
 216 static void raw_size(void) {
 217     /* Do nothing! */
 218     return;
 219 }
 220
 221 /*
 222  * Send raw special codes.
 223  */
 224 static void raw_special (Telnet_Special code) {
 225     /* Do nothing! */
 226     return;
 227 }
 228
 229 Backend raw_backend = {
 230     raw_init,
 231     raw_msg,
 232     raw_send,
 233     raw_size,
 234     raw_special
 235 };