1 #include <u.h>
2 #include <libc.h>
3 #include <regexp.h>
4 #include <thread.h>
5 #include <fcall.h>
6 
7 int debug;
8 int dfd;
9 int srvfd;
10 int netfd[2];
11 int srv_to_net[2];
12 int net_to_srv[2];
13 char *srv;
14 char	*addr;
15 char *ns;
16 int export;
17 
18 void	shuffle(void *arg);
19 int	post(char *srv);
20 void	remoteside(void*);
21 int	call(char *rsys, char *ns, char *srv);
22 void*	emalloc(int size);
23 void	localside(void*);
24 
25 char *REXEXEC = "ssh";
26 char *prog = "import";
27 
28 enum
29 {
30 	Stack= 32*1024
31 };
32 
33 void
34 usage(void)
35 {
36 	fprint(2, "usage: %s [-df] [-s service] [-n remote-ns] [-p remote-prog] remote-system\n", argv0);
37 	threadexitsall("usage");
38 }
39 
40 void
41 fatal(char *fmt, ...)
42 {
43 	char buf[256];
44 	va_list arg;
45 
46 	va_start(arg, fmt);
47 	vseprint(buf, buf+sizeof buf, fmt, arg);
48 	va_end(arg);
49 
50 	fprint(2, "%s: %s\n", argv0 ? argv0 : "<prog>", buf);
51 	threadexitsall("fatal");
52 }
53 
54 void
55 threadmain(int argc, char *argv[])
56 {
57 	int dofork;
58 	int rem;
59 	void (*fn)(void*);
60 
61 	dofork = 1;
62 	rem = 0;
63 	ns = nil;
64 	srv = "plumb";
65 
66 	ARGBEGIN{
67 	case 'd':
68 		debug = 1;
69 		break;
70 	case 'f':
71 		dofork = 0;
72 		break;
73 	case 'n':	/* name of remote namespace */
74 		ns = EARGF(usage());
75 		break;
76 	case 'p':
77 		prog = EARGF(usage());
78 		break;
79 	case 's':	/* name of service */
80 		srv = EARGF(usage());
81 		break;
82 	case 'R':
83 		rem = 1;
84 		break;
85 	case 'x':
86 		export = 1;
87 		break;
88 	}ARGEND
89 
90 	if(debug){
91 		char *dbgfile;
92 
93 		if(rem)
94 			dbgfile = smprint("/tmp/%s.export.debug", getuser());
95 		else
96 			dbgfile = smprint("/tmp/%s.import.debug", getuser());
97 		dfd = create(dbgfile, OWRITE, 0664);
98 		free(dbgfile);
99 		fmtinstall('F', fcallfmt);
100 	}
101 
102 	
103 	if(rem){
104 		netfd[0] = 0;
105 		netfd[1] = 1;	
106 		write(1, "OK", 2);
107 	}else{
108 		if(argc != 1)
109 			usage();
110 		addr = argv[0];
111 		/* connect to remote service */
112 		netfd[0] = netfd[1] = call(addr, ns, srv);
113 	}
114 
115 	fn = localside;
116 	if(rem+export == 1)
117 		fn = remoteside;
118 	
119 	if(rem || !dofork)
120 		fn(nil);
121 	else
122 		proccreate(fn, nil, Stack);
123 }
124 
125 
126 void
127 localside(void *arg)
128 {
129 	USED(arg);
130 
131 	/* start a loal service */
132 	srvfd = post(srv);
133 
134 	/* threads to shuffle messages each way */
135 	srv_to_net[0] = srvfd;
136 	srv_to_net[1] = netfd[1];
137 	proccreate(shuffle, srv_to_net, Stack);
138 	net_to_srv[0] = netfd[0];
139 	net_to_srv[1] = srvfd;
140 	shuffle(net_to_srv);
141 }
142 
143 /* post a local service */
144 int
145 post(char *srv)
146 {
147 	int p[2];
148 
149 	if(pipe(p) < 0)
150 		fatal("can't create pipe: %r");
151 
152 	/* 0 will be server end, 1 will be client end */
153 	if(post9pservice(p[1], srv, nil) < 0)
154 		fatal("post9pservice plumb: %r");
155 	close(p[1]);
156 
157 	return p[0];
158 }
159 
160 /* start a stub on the remote server */
161 int
162 call(char *rsys, char *ns, char *srv)
163 {
164 	int p[2];
165 	int ac;
166 	char *av[12];
167 	char buf[2];
168 
169 	if(pipe(p) < 0)
170 		fatal("can't create pipe: %r");
171 	ac = 0;
172 	av[ac++] = REXEXEC;
173 	av[ac++] = rsys;
174 	av[ac++] = prog;
175 	if(debug)
176 		av[ac++] = "-d";
177 	av[ac++] = "-R";
178 	if(ns != nil){
179 		av[ac++] = "-n";
180 		av[ac++] = ns;
181 	}
182 	av[ac++] = "-s";
183 	av[ac++] = srv;
184 	if(export)
185 		av[ac++] = "-x";
186 	av[ac] = 0;
187 
188 	if(debug){
189 		fprint(dfd, "execing ");
190 		for(ac = 0; av[ac]; ac++)
191 			fprint(dfd, " %s", av[ac]);
192 		fprint(dfd, "\n");
193 	}
194 
195 	switch(fork()){
196 	case -1:
197 		fatal("%r");
198 	case 0:
199 		dup(p[1], 0);
200 		dup(p[1], 1);
201 		close(p[0]);
202 		close(p[1]);
203 		execvp(REXEXEC, av);
204 		fatal("can't exec %s", REXEXEC);
205 	default:
206 		break;
207 	}
208 	close(p[1]);
209 
210 	/* ignore crap that might come out of the .profile */
211 	/* keep reading till we have an "OK" */
212 	if(read(p[0], &buf[0], 1) != 1)
213 		fatal("EOF");
214 	for(;;){
215 		if(read(p[0], &buf[1], 1) != 1)
216 			fatal("EOF");
217 		if(strncmp(buf, "OK", 2) == 0)
218 			break;
219 		buf[0] = buf[1];
220 	}
221 	if(debug)
222 		fprint(dfd, "got OK\n");
223 
224 	return p[0];
225 }
226 
227 enum
228 {
229 	BLEN=16*1024
230 };
231 
232 void
233 shuffle(void *arg)
234 {
235 	int *fd;
236 	char *buf, *tbuf;
237 	int n;
238 	Fcall *t;
239 
240 	fd = (int*)arg;
241 	buf = emalloc(BLEN+1);
242 	t = nil;
243 	tbuf = nil;
244 	for(;;){
245 		n = read9pmsg(fd[0], buf, BLEN);
246 		if(n <= 0){
247 			if(debug)
248 				fprint(dfd, "%d->%d read returns %d: %r\n", fd[0], fd[1], n);
249 			break;
250 		}
251 		if(debug){
252 			if(t == nil)
253 				t = emalloc(sizeof(Fcall));
254 			if(tbuf == nil)
255 				tbuf = emalloc(BLEN+1);
256 			memmove(tbuf, buf, n);	/* because convM2S is destructive */
257 			if(convM2S((uchar*)tbuf, n, t) != n)
258 				fprint(dfd, "%d->%d convert error in convM2S", fd[0], fd[1]);
259 			else
260 				fprint(dfd, "%d->%d %F\n", fd[0], fd[1], t);
261 		}
262 		if(write(fd[1], buf, n) != n)
263 			break;
264 	}
265 	threadexitsall(0);
266 }
267 
268 void
269 remoteside(void *v)
270 {
271 	int srv_to_net[2];
272 	int net_to_srv[2];
273 	char *addr;
274 	int srvfd;
275 
276 	if(ns == nil)
277 		ns = getns();
278 
279 	addr = smprint("unix!%s/%s", ns, srv);
280 	if(addr == nil)
281 		fatal("%r");
282 	if(debug)
283 		fprint(dfd, "remoteside starting %s\n", addr);
284 
285 	srvfd = dial(addr, 0, 0, 0);
286 	if(srvfd < 0)
287 		fatal("dial %s: %r", addr);
288 	if(debug)
289 		fprint(dfd, "remoteside dial %s succeeded\n", addr);
290 	fcntl(srvfd, F_SETFL, FD_CLOEXEC);
291 
292 	/* threads to shuffle messages each way */
293 	srv_to_net[0] = srvfd;
294 	srv_to_net[1] = netfd[1];
295 	proccreate(shuffle, srv_to_net, Stack);
296 	net_to_srv[0] = netfd[0];
297 	net_to_srv[1] = srvfd;
298 	shuffle(net_to_srv);
299 
300 	threadexitsall(0);
301 }
302 
303 void*
304 emalloc(int size)
305 {
306 	void *x;
307 
308 	x = malloc(size);
309 	if(x == nil)
310 		fatal("allocation fails: %r");
311 	return x;
312 }