1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
/*
* Windows support module which deals with being a named-pipe server.
*/
#include <stdio.h>
#include <assert.h>
#include "tree234.h"
#include "putty.h"
#include "network.h"
#include "proxy/proxy.h"
#include "ssh.h"
#include "security-api.h"
typedef struct NamedPipeServerSocket {
/* Parameters for (repeated) creation of named pipe objects */
PSECURITY_DESCRIPTOR psd;
PACL acl;
char *pipename;
/* The current named pipe object + attempt to connect to it */
HANDLE pipehandle;
OVERLAPPED connect_ovl;
HandleWait *callback_handle; /* handle-wait.c's reference */
/* PuTTY Socket machinery */
Plug *plug;
char *error;
Socket sock;
} NamedPipeServerSocket;
static Plug *sk_namedpipeserver_plug(Socket *s, Plug *p)
{
NamedPipeServerSocket *ps = container_of(s, NamedPipeServerSocket, sock);
Plug *ret = ps->plug;
if (p)
ps->plug = p;
return ret;
}
static void sk_namedpipeserver_close(Socket *s)
{
NamedPipeServerSocket *ps = container_of(s, NamedPipeServerSocket, sock);
if (ps->callback_handle)
delete_handle_wait(ps->callback_handle);
CloseHandle(ps->pipehandle);
CloseHandle(ps->connect_ovl.hEvent);
sfree(ps->error);
sfree(ps->pipename);
if (ps->acl)
LocalFree(ps->acl);
if (ps->psd)
LocalFree(ps->psd);
sfree(ps);
}
static const char *sk_namedpipeserver_socket_error(Socket *s)
{
NamedPipeServerSocket *ps = container_of(s, NamedPipeServerSocket, sock);
return ps->error;
}
static SocketPeerInfo *sk_namedpipeserver_peer_info(Socket *s)
{
return NULL;
}
static bool create_named_pipe(NamedPipeServerSocket *ps, bool first_instance)
{
SECURITY_ATTRIBUTES sa;
memset(&sa, 0, sizeof(sa));
sa.nLength = sizeof(sa);
sa.lpSecurityDescriptor = ps->psd;
sa.bInheritHandle = false;
ps->pipehandle = CreateNamedPipe(
/* lpName */
ps->pipename,
/* dwOpenMode */
PIPE_ACCESS_DUPLEX |
FILE_FLAG_OVERLAPPED |
(first_instance ? FILE_FLAG_FIRST_PIPE_INSTANCE : 0),
/* dwPipeMode */
PIPE_TYPE_BYTE | PIPE_READMODE_BYTE | PIPE_WAIT
#ifdef PIPE_REJECT_REMOTE_CLIENTS
| PIPE_REJECT_REMOTE_CLIENTS
#endif
,
/* nMaxInstances */
PIPE_UNLIMITED_INSTANCES,
/* nOutBufferSize, nInBufferSize */
4096, 4096, /* FIXME: think harder about buffer sizes? */
/* nDefaultTimeOut */
0 /* default timeout */,
/* lpSecurityAttributes */
&sa);
return ps->pipehandle != INVALID_HANDLE_VALUE;
}
static Socket *named_pipe_accept(accept_ctx_t ctx, Plug *plug)
{
HANDLE conn = (HANDLE)ctx.p;
return make_handle_socket(conn, conn, NULL, NULL, 0, plug, true);
}
static void named_pipe_accept_loop(NamedPipeServerSocket *ps,
bool got_one_already)
{
while (1) {
int error;
char *errmsg;
if (got_one_already) {
/* If we were called with a connection already waiting,
* skip this step. */
got_one_already = false;
error = 0;
} else {
/*
* Call ConnectNamedPipe, which might succeed or might
* tell us that an overlapped operation is in progress and
* we should wait for our event object.
*/
if (ConnectNamedPipe(ps->pipehandle, &ps->connect_ovl))
error = 0;
else
error = GetLastError();
if (error == ERROR_IO_PENDING)
return;
}
if (error == 0 || error == ERROR_PIPE_CONNECTED) {
/*
* We've successfully retrieved an incoming connection, so
* ps->pipehandle now refers to that connection. So
* convert that handle into a separate connection-type
* Socket, and create a fresh one to be the new listening
* pipe.
*/
HANDLE conn = ps->pipehandle;
accept_ctx_t actx;
actx.p = (void *)conn;
if (plug_accepting(ps->plug, named_pipe_accept, actx)) {
/*
* If the plug didn't want the connection, might as
* well close this handle.
*/
CloseHandle(conn);
}
if (!create_named_pipe(ps, false)) {
error = GetLastError();
} else {
/*
* Go round again to see if more connections can be
* got, or to begin waiting on the event object.
*/
continue;
}
}
errmsg = dupprintf("Error while listening to named pipe: %s",
win_strerror(error));
plug_log(ps->plug, 1, sk_namedpipe_addr(ps->pipename), 0,
errmsg, error);
sfree(errmsg);
break;
}
}
static void named_pipe_connect_callback(void *vps)
{
NamedPipeServerSocket *ps = (NamedPipeServerSocket *)vps;
named_pipe_accept_loop(ps, true);
}
/*
* This socket type is only used for listening, so it should never
* be asked to write or set_frozen.
*/
static const SocketVtable NamedPipeServerSocket_sockvt = {
.plug = sk_namedpipeserver_plug,
.close = sk_namedpipeserver_close,
.socket_error = sk_namedpipeserver_socket_error,
.peer_info = sk_namedpipeserver_peer_info,
};
Socket *new_named_pipe_listener(const char *pipename, Plug *plug)
{
NamedPipeServerSocket *ret = snew(NamedPipeServerSocket);
ret->sock.vt = &NamedPipeServerSocket_sockvt;
ret->plug = plug;
ret->error = NULL;
ret->psd = NULL;
ret->pipename = dupstr(pipename);
ret->acl = NULL;
ret->callback_handle = NULL;
assert(strncmp(pipename, "\\\\.\\pipe\\", 9) == 0);
assert(strchr(pipename + 9, '\\') == NULL);
if (!make_private_security_descriptor(GENERIC_READ | GENERIC_WRITE,
&ret->psd, &ret->acl, &ret->error)) {
goto cleanup;
}
if (!create_named_pipe(ret, true)) {
ret->error = dupprintf("unable to create named pipe '%s': %s",
pipename, win_strerror(GetLastError()));
goto cleanup;
}
memset(&ret->connect_ovl, 0, sizeof(ret->connect_ovl));
ret->connect_ovl.hEvent = CreateEvent(NULL, true, false, NULL);
ret->callback_handle = add_handle_wait(
ret->connect_ovl.hEvent, named_pipe_connect_callback, ret);
named_pipe_accept_loop(ret, false);
cleanup:
return &ret->sock;
}
|
