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 int
55 threadmaybackground(void)
56 {
57 	return 1;
58 }
59 
60 void
61 threadmain(int argc, char *argv[])
62 {
63 	int dofork;
64 	int rem;
65 	void (*fn)(void*);
66 
67 	dofork = 1;
68 	rem = 0;
69 	ns = nil;
70 	srv = "plumb";
71 
72 	ARGBEGIN{
73 	case 'd':
74 		debug = 1;
75 		break;
76 	case 'f':
77 		dofork = 0;
78 		break;
79 	case 'n':	/* name of remote namespace */
80 		ns = EARGF(usage());
81 		break;
82 	case 'p':
83 		prog = EARGF(usage());
84 		break;
85 	case 's':	/* name of service */
86 		srv = EARGF(usage());
87 		break;
88 	case 'R':
89 		rem = 1;
90 		break;
91 	case 'x':
92 		export = 1;
93 		break;
94 	}ARGEND
95 
96 	if(debug){
97 		char *dbgfile;
98 
99 		if(rem)
100 			dbgfile = smprint("/tmp/%s.export.debug", getuser());
101 		else
102 			dbgfile = smprint("/tmp/%s.import.debug", getuser());
103 		dfd = create(dbgfile, OWRITE, 0664);
104 		free(dbgfile);
105 		fmtinstall('F', fcallfmt);
106 	}
107 
108 
109 	if(rem){
110 		netfd[0] = 0;
111 		netfd[1] = 1;
112 		write(1, "OK", 2);
113 	}else{
114 		if(argc != 1)
115 			usage();
116 		addr = argv[0];
117 		/* connect to remote service */
118 		netfd[0] = netfd[1] = call(addr, ns, srv);
119 	}
120 
121 	fn = localside;
122 	if(rem+export == 1)
123 		fn = remoteside;
124 
125 	if(rem || !dofork)
126 		fn(nil);
127 	else
128 		proccreate(fn, nil, Stack);
129 }
130 
131 
132 void
133 localside(void *arg)
134 {
135 	USED(arg);
136 
137 	/* start a loal service */
138 	srvfd = post(srv);
139 
140 	/* threads to shuffle messages each way */
141 	srv_to_net[0] = srvfd;
142 	srv_to_net[1] = netfd[1];
143 	proccreate(shuffle, srv_to_net, Stack);
144 	net_to_srv[0] = netfd[0];
145 	net_to_srv[1] = srvfd;
146 	shuffle(net_to_srv);
147 }
148 
149 /* post a local service */
150 int
151 post(char *srv)
152 {
153 	int p[2];
154 
155 	if(pipe(p) < 0)
156 		fatal("can't create pipe: %r");
157 
158 	/* 0 will be server end, 1 will be client end */
159 	if(post9pservice(p[1], srv, nil) < 0)
160 		fatal("post9pservice plumb: %r");
161 	close(p[1]);
162 
163 	return p[0];
164 }
165 
166 /* start a stub on the remote server */
167 int
168 call(char *rsys, char *ns, char *srv)
169 {
170 	int p[2];
171 	int ac;
172 	char *av[12];
173 	char buf[2];
174 
175 	if(pipe(p) < 0)
176 		fatal("can't create pipe: %r");
177 	ac = 0;
178 	av[ac++] = REXEXEC;
179 	av[ac++] = rsys;
180 	av[ac++] = prog;
181 	if(debug)
182 		av[ac++] = "-d";
183 	av[ac++] = "-R";
184 	if(ns != nil){
185 		av[ac++] = "-n";
186 		av[ac++] = ns;
187 	}
188 	av[ac++] = "-s";
189 	av[ac++] = srv;
190 	if(export)
191 		av[ac++] = "-x";
192 	av[ac] = 0;
193 
194 	if(debug){
195 		fprint(dfd, "execing ");
196 		for(ac = 0; av[ac]; ac++)
197 			fprint(dfd, " %s", av[ac]);
198 		fprint(dfd, "\n");
199 	}
200 
201 	switch(fork()){
202 	case -1:
203 		fatal("%r");
204 	case 0:
205 		dup(p[1], 0);
206 		dup(p[1], 1);
207 		close(p[0]);
208 		close(p[1]);
209 		execvp(REXEXEC, av);
210 		fatal("can't exec %s", REXEXEC);
211 	default:
212 		break;
213 	}
214 	close(p[1]);
215 
216 	/* ignore crap that might come out of the .profile */
217 	/* keep reading till we have an "OK" */
218 	if(read(p[0], &buf[0], 1) != 1)
219 		fatal("EOF");
220 	for(;;){
221 		if(read(p[0], &buf[1], 1) != 1)
222 			fatal("EOF");
223 		if(strncmp(buf, "OK", 2) == 0)
224 			break;
225 		buf[0] = buf[1];
226 	}
227 	if(debug)
228 		fprint(dfd, "got OK\n");
229 
230 	return p[0];
231 }
232 
233 enum
234 {
235 	BLEN=16*1024
236 };
237 
238 void
239 shuffle(void *arg)
240 {
241 	int *fd;
242 	char *buf, *tbuf;
243 	int n;
244 	Fcall *t;
245 
246 	fd = (int*)arg;
247 	buf = emalloc(BLEN+1);
248 	t = nil;
249 	tbuf = nil;
250 	for(;;){
251 		n = read9pmsg(fd[0], buf, BLEN);
252 		if(n <= 0){
253 			if(debug)
254 				fprint(dfd, "%d->%d read returns %d: %r\n", fd[0], fd[1], n);
255 			break;
256 		}
257 		if(debug){
258 			if(t == nil)
259 				t = emalloc(sizeof(Fcall));
260 			if(tbuf == nil)
261 				tbuf = emalloc(BLEN+1);
262 			memmove(tbuf, buf, n);	/* because convM2S is destructive */
263 			if(convM2S((uchar*)tbuf, n, t) != n)
264 				fprint(dfd, "%d->%d convert error in convM2S", fd[0], fd[1]);
265 			else
266 				fprint(dfd, "%d->%d %F\n", fd[0], fd[1], t);
267 		}
268 		if(write(fd[1], buf, n) != n)
269 			break;
270 	}
271 	threadexitsall(0);
272 }
273 
274 void
275 remoteside(void *v)
276 {
277 	int srv_to_net[2];
278 	int net_to_srv[2];
279 	char *addr;
280 	int srvfd;
281 
282 	if(ns == nil)
283 		ns = getns();
284 
285 	addr = smprint("unix!%s/%s", ns, srv);
286 	if(addr == nil)
287 		fatal("%r");
288 	if(debug)
289 		fprint(dfd, "remoteside starting %s\n", addr);
290 
291 	srvfd = dial(addr, 0, 0, 0);
292 	if(srvfd < 0)
293 		fatal("dial %s: %r", addr);
294 	if(debug)
295 		fprint(dfd, "remoteside dial %s succeeded\n", addr);
296 	fcntl(srvfd, F_SETFL, FD_CLOEXEC);
297 
298 	/* threads to shuffle messages each way */
299 	srv_to_net[0] = srvfd;
300 	srv_to_net[1] = netfd[1];
301 	proccreate(shuffle, srv_to_net, Stack);
302 	net_to_srv[0] = netfd[0];
303 	net_to_srv[1] = srvfd;
304 	shuffle(net_to_srv);
305 
306 	threadexitsall(0);
307 }
308 
309 void*
310 emalloc(int size)
311 {
312 	void *x;
313 
314 	x = malloc(size);
315 	if(x == nil)
316 		fatal("allocation fails: %r");
317 	return x;
318 }