Mark Baker's raw-TCP back end (untested and experimental as yet)
[u/mdw/putty] / 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 }
60 }
61 }
62
63 /*
64 * Called to set up the raw connection. Will arrange for
65 * WM_NETEVENT messages to be passed to the specified window, whose
66 * window procedure should then call raw_msg().
67 *
68 * Returns an error message, or NULL on success.
69 *
70 * Also places the canonical host name into `realhost'.
71 */
72 static char *raw_init (HWND hwnd, char *host, int port, char **realhost) {
73 SOCKADDR_IN addr;
74 struct hostent *h;
75 unsigned long a;
76
77 /*
78 * Try to find host.
79 */
80 if ( (a = inet_addr(host)) == (unsigned long) INADDR_NONE) {
81 if ( (h = gethostbyname(host)) == NULL)
82 switch (WSAGetLastError()) {
83 case WSAENETDOWN: return "Network is down";
84 case WSAHOST_NOT_FOUND: case WSANO_DATA:
85 return "Host does not exist";
86 case WSATRY_AGAIN: return "Host not found";
87 default: return "gethostbyname: unknown error";
88 }
89 memcpy (&a, h->h_addr, sizeof(a));
90 *realhost = h->h_name;
91 } else
92 *realhost = host;
93 a = ntohl(a);
94
95 if (port < 0)
96 port = 23; /* default telnet port */
97
98 /*
99 * Open socket.
100 */
101 s = socket(AF_INET, SOCK_STREAM, 0);
102 if (s == INVALID_SOCKET)
103 switch (WSAGetLastError()) {
104 case WSAENETDOWN: return "Network is down";
105 case WSAEAFNOSUPPORT: return "TCP/IP support not present";
106 default: return "socket(): unknown error";
107 }
108
109 /*
110 * Bind to local address.
111 */
112 addr.sin_family = AF_INET;
113 addr.sin_addr.s_addr = htonl(INADDR_ANY);
114 addr.sin_port = htons(0);
115 if (bind (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
116 switch (WSAGetLastError()) {
117 case WSAENETDOWN: return "Network is down";
118 default: return "bind(): unknown error";
119 }
120
121 /*
122 * Connect to remote address.
123 */
124 addr.sin_addr.s_addr = htonl(a);
125 addr.sin_port = htons((short)port);
126 if (connect (s, (struct sockaddr *)&addr, sizeof(addr)) == SOCKET_ERROR)
127 switch (WSAGetLastError()) {
128 case WSAENETDOWN: return "Network is down";
129 case WSAECONNREFUSED: return "Connection refused";
130 case WSAENETUNREACH: return "Network is unreachable";
131 case WSAEHOSTUNREACH: return "No route to host";
132 default: return "connect(): unknown error";
133 }
134
135 if (WSAAsyncSelect (s, hwnd, WM_NETEVENT, FD_READ |
136 FD_WRITE | FD_OOB | FD_CLOSE) == SOCKET_ERROR)
137 switch (WSAGetLastError()) {
138 case WSAENETDOWN: return "Network is down";
139 default: return "WSAAsyncSelect(): unknown error";
140 }
141
142 return NULL;
143 }
144
145 /*
146 * Process a WM_NETEVENT message. Will return 0 if the connection
147 * has closed, or <0 for a socket error.
148 */
149 static int raw_msg (WPARAM wParam, LPARAM lParam) {
150 int ret;
151 char buf[256];
152
153 if (s == INVALID_SOCKET) /* how the hell did we get here?! */
154 return -5000;
155
156 if (WSAGETSELECTERROR(lParam) != 0)
157 return -WSAGETSELECTERROR(lParam);
158
159 switch (WSAGETSELECTEVENT(lParam)) {
160 case FD_READ:
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; /* can't happen, in theory */
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 case FD_CLOSE:
188 s = INVALID_SOCKET;
189 return 0;
190 }
191 return 1; /* shouldn't happen, but WTF */
192 }
193
194 /*
195 * Called to send data down the raw connection.
196 */
197 static void raw_send (char *buf, int len) {
198
199 if (s == INVALID_SOCKET)
200 return;
201
202 s_write( buf, len );
203 }
204
205 /*
206 * Called to set the size of the window
207 */
208 static void raw_size(void) {
209 /* Do nothing! */
210 return;
211 }
212
213 /*
214 * Send raw special codes.
215 */
216 static void raw_special (Telnet_Special code) {
217 /* Do nothing! */
218 return;
219 }
220
221 Backend raw_backend = {
222 raw_init,
223 raw_msg,
224 raw_send,
225 raw_size,
226 raw_special
227 };