1 #include <u.h>
2 #include <libc.h>
3 #include <bio.h>
4 #include <ndb.h>
5 #include <mp.h>
6 #include <libsec.h>
7 #include "SConn.h"
8 #include "secstore.h"
9 
10 char *SECSTORE_DIR;
11 char* secureidcheck(char *, char *);   /* from /sys/src/cmd/auth/ */
12 extern char* dirls(char *path);
13 
14 int verbose;
15 Ndb *db;
16 
17 static void
18 usage(void)
19 {
20 	fprint(2, "usage: secstored [-R] [-S servername] [-s tcp!*!5356] [-v] [-x netmtpt]\n");
21 	exits("usage");
22 }
23 
24 static int
25 getdir(SConn *conn, char *id)
26 {
27 	char *ls, *s; 
28 	uchar *msg;
29 	int n, len;
30 
31 	s = emalloc(Maxmsg);
32 	snprint(s, Maxmsg, "%s/store/%s", SECSTORE_DIR, id);
33 
34 	if((ls = dirls(s)) == nil)
35 		len = 0;
36 	else
37 		len = strlen(ls);
38 
39 	/* send file size */
40 	snprint(s, Maxmsg, "%d", len);
41 	conn->write(conn, (uchar*)s, strlen(s));
42 
43 	/* send directory listing in Maxmsg chunks */
44 	n = Maxmsg;
45 	msg = (uchar*)ls;
46 	while(len > 0){
47 		if(len < Maxmsg)
48 			n = len;
49 		conn->write(conn, msg, n);
50 		msg += n;
51 		len -= n;
52 	}
53 	free(s);
54 	free(ls);
55 	return 0;
56 }
57 
58 char *
59 validatefile(char *f)
60 {
61 	char *nl;
62 
63 	if(f==nil || *f==0)
64 		return nil;
65 	if(nl = strchr(f, '\n'))
66 		*nl = 0;
67 	if(strchr(f,'/') != nil || strcmp(f,"..")==0 || strlen(f) >= 300){
68 		syslog(0, LOG, "no slashes allowed: %s\n", f);
69 		return nil;
70 	}
71 	return f;
72 }
73 
74 static int
75 getfile(SConn *conn, char *id, char *gf)
76 {
77 	int n, gd, len;
78 	ulong mode;
79 	char *s;
80 	Dir *st;
81 
82 	if(strcmp(gf,".")==0)
83 		return getdir(conn, id);
84 
85 	/* send file size */
86 	s = emalloc(Maxmsg);
87 	snprint(s, Maxmsg, "%s/store/%s/%s", SECSTORE_DIR, id, gf);
88 	gd = open(s, OREAD);
89 	if(gd < 0){
90 		syslog(0, LOG, "can't open %s: %r\n", s);
91 		free(s);
92 		conn->write(conn, (uchar*)"-1", 2);
93 		return -1;
94 	}
95 	st = dirfstat(gd);
96 	if(st == nil){
97 		syslog(0, LOG, "can't stat %s: %r\n", s);
98 		free(s);
99 		conn->write(conn, (uchar*)"-1", 2);
100 		return -1;
101 	}
102 	mode = st->mode;
103 	len = st->length;
104 	free(st);
105 	if(mode & DMDIR) {
106 		syslog(0, LOG, "%s should be a plain file, not a directory\n", s);
107 		free(s);
108 		conn->write(conn, (uchar*)"-1", 2);
109 		return -1;
110 	}
111 	if(len < 0 || len > MAXFILESIZE){
112 		syslog(0, LOG, "implausible filesize %d for %s\n", len, gf);
113 		free(s);
114 		conn->write(conn, (uchar*)"-3", 2);
115 		return -1;
116 	}
117 	snprint(s, Maxmsg, "%d", len);
118 	conn->write(conn, (uchar*)s, strlen(s));
119 
120 	/* send file in Maxmsg chunks */
121 	while(len > 0){
122 		n = read(gd, s, Maxmsg);
123 		if(n <= 0){
124 			syslog(0, LOG, "read error on %s: %r\n", gf);
125 			free(s);
126 			return -1;
127 		}
128 		conn->write(conn, (uchar*)s, n);
129 		len -= n;
130 	}
131 	close(gd);
132 	free(s);
133 	return 0;
134 }
135 
136 static int
137 putfile(SConn *conn, char *id, char *pf)
138 {
139 	int n, nw, pd;
140 	long len;
141 	char s[Maxmsg+1];
142 
143 	/* get file size */
144 	n = readstr(conn, s);
145 	if(n < 0){
146 		syslog(0, LOG, "remote: %s: %r\n", s);
147 		return -1;
148 	}
149 	len = atoi(s);
150 	if(len == -1){
151 		syslog(0, LOG, "remote file %s does not exist\n", pf);
152 		return -1;
153 	}else if(len < 0 || len > MAXFILESIZE){
154 		syslog(0, LOG, "implausible filesize %ld for %s\n", len, pf);
155 		return -1;
156 	}
157 
158 	/* get file in Maxmsg chunks */
159 	if(strchr(pf,'/') != nil || strcmp(pf,"..")==0){
160 		syslog(0, LOG, "no slashes allowed: %s\n", pf);
161 		return -1;
162 	}
163 	snprint(s, Maxmsg, "%s/store/%s/%s", SECSTORE_DIR, id, pf);
164 	pd = create(s, OWRITE, 0660);
165 	if(pd < 0){
166 		syslog(0, LOG, "can't open %s: %r\n", s);
167 		return -1;
168 	}
169 	while(len > 0){
170 		n = conn->read(conn, (uchar*)s, Maxmsg);
171 		if(n <= 0){
172 			syslog(0, LOG, "empty file chunk\n");
173 			return -1;
174 		}
175 		nw = write(pd, s, n);
176 		if(nw != n){
177 			syslog(0, LOG, "write error on %s: %r", pf);
178 			return -1;
179 		}
180 		len -= n;
181 	}
182 	close(pd);
183 	return 0;
184 
185 }
186 
187 static int
188 removefile(SConn *conn, char *id, char *f)
189 {
190 	Dir *d;
191 	char buf[Maxmsg];
192 
193 	snprint(buf, Maxmsg, "%s/store/%s/%s", SECSTORE_DIR, id, f);
194 
195 	if((d = dirstat(buf)) == nil){
196 		snprint(buf, sizeof buf, "remove failed: %r");
197 		writerr(conn, buf);
198 		return -1;
199 	}else if(d->mode & DMDIR){
200 		snprint(buf, sizeof buf, "can't remove a directory");
201 		writerr(conn, buf);
202 		free(d);
203 		return -1;
204 	}
205 
206 	free(d);
207 	if(remove(buf) < 0){
208 		snprint(buf, sizeof buf, "remove failed: %r");
209 		writerr(conn, buf);
210 		return -1;
211 	}
212 	return 0;
213 }
214 
215 /* given line directory from accept, returns ipaddr!port */
216 static char*
217 remoteIP(char *ldir)
218 {
219 	int fd, n;
220 	char rp[100], ap[500];
221 
222 	snprint(rp, sizeof rp, "%s/remote", ldir);
223 	fd = open(rp, OREAD);
224 	if(fd < 0)
225 		return strdup("?!?");
226 	n = read(fd, ap, sizeof ap);
227 	if(n <= 0 || n == sizeof ap){
228 		fprint(2, "error %d reading %s: %r\n", n, rp);
229 		return strdup("?!?");
230 	}
231 	close(fd);
232 	ap[n--] = 0;
233 	if(ap[n] == '\n')
234 		ap[n] = 0;
235 	return strdup(ap);
236 }
237 
238 static int
239 dologin(int fd, char *S, int forceSTA)
240 {
241 	int i, n, rv;
242 	char *file, *mess;
243 	char msg[Maxmsg+1];
244 	PW *pw;
245 	SConn *conn;
246 
247 	pw = nil;
248 	rv = -1;
249 
250 	/* collect the first message */
251 	if((conn = newSConn(fd)) == nil)
252 		return -1;
253 	if(readstr(conn, msg) < 0){
254 		fprint(2, "remote: %s: %r\n", msg);
255 		writerr(conn, "can't read your first message");
256 		goto Out;
257 	}
258 
259 	/* authenticate */
260 	if(PAKserver(conn, S, msg, &pw) < 0){
261 		if(pw != nil)
262 			syslog(0, LOG, "secstore denied for %s", pw->id);
263 		goto Out;
264 	}
265 	if((forceSTA || pw->status&STA) != 0){
266 		conn->write(conn, (uchar*)"STA", 3);
267 		if(readstr(conn, msg) < 10 || strncmp(msg, "STA", 3) != 0){
268 			syslog(0, LOG, "no STA from %s", pw->id);
269 			goto Out;
270 		}
271 		mess = secureidcheck(pw->id, msg+3);
272 		if(mess != nil){
273 			syslog(0, LOG, "secureidcheck denied %s because %s", pw->id, mess);
274 			goto Out;
275 		}
276 	}
277 	conn->write(conn, (uchar*)"OK", 2);
278 	syslog(0, LOG, "AUTH %s", pw->id);
279 
280 	/* perform operations as asked */
281 	while((n = readstr(conn, msg)) > 0){
282 		syslog(0, LOG, "[%s] %s", pw->id, msg);
283 
284 		if(strncmp(msg, "GET ", 4) == 0){
285 			file = validatefile(msg+4);
286 			if(file==nil || getfile(conn, pw->id, file) < 0)
287 				goto Err;
288 
289 		}else if(strncmp(msg, "PUT ", 4) == 0){
290 			file = validatefile(msg+4);
291 			if(file==nil || putfile(conn, pw->id, file) < 0){
292 				syslog(0, LOG, "failed PUT %s/%s", pw->id, file);
293 				goto Err;
294 			}
295 
296 		}else if(strncmp(msg, "RM ", 3) == 0){
297 			file = validatefile(msg+3);
298 			if(file==nil || removefile(conn, pw->id, file) < 0){
299 				syslog(0, LOG, "failed RM %s/%s", pw->id, file);
300 				goto Err;
301 			}
302 
303 		}else if(strncmp(msg, "CHPASS", 6) == 0){
304 			if(readstr(conn, msg) < 0){
305 				syslog(0, LOG, "protocol botch CHPASS for %s", pw->id);
306 				writerr(conn, "protocol botch while setting PAK");
307 				goto Out;
308 			}
309 			pw->Hi = strtomp(msg, nil, 64, pw->Hi);
310 			for(i=0; i < 4 && putPW(pw) < 0; i++)
311 				syslog(0, LOG, "password change failed for %s (%d): %r", pw->id, i);
312 			if(i==4)
313 				goto Out;
314 
315 		}else if(strncmp(msg, "BYE", 3) == 0){
316 			rv = 0;
317 			break;
318 
319 		}else{
320 			writerr(conn, "unrecognized operation");
321 			break;
322 		}
323 
324 	}
325 	if(n <= 0)
326 		syslog(0, LOG, "%s closed connection without saying goodbye\n", pw->id);
327 
328 Out:
329 	freePW(pw);
330 	conn->free(conn);
331 	return rv;
332 Err:
333 	writerr(conn, "operation failed");
334 	goto Out;
335 }
336 
337 void
338 main(int argc, char **argv)
339 {
340 	int afd, dfd, lcfd, forceSTA = 0;
341 	char adir[40], ldir[40], *remote;
342 	char *serve = "tcp!*!5356", *p, aserve[128];
343 	char *S = "secstore";
344 	char *dbpath;
345 	Ndb *db2;
346 
347 	S = sysname();
348 	SECSTORE_DIR = unsharp("#9/secstore");
349 /*	setnetmtpt(net, sizeof(net), nil); */
350 	ARGBEGIN{
351 	case 'R':
352 		forceSTA = 1;
353 		break;
354 	case 's':
355 		serve = EARGF(usage());
356 		break;
357 	case 'S':
358 		S = EARGF(usage());
359 		break;
360 	case 'x':
361 		p = ARGF();
362 		if(p == nil)
363 			usage();
364 		USED(p);
365 	/*	setnetmtpt(net, sizeof(net), p); */
366 		break;
367 	case 'v':
368 		verbose++;
369 		break;
370 	default:
371 		usage();
372 	}ARGEND;
373 
374 	if(!verbose)
375 		switch(rfork(RFNOTEG|RFPROC|RFFDG)) {
376 		case -1:
377 			sysfatal("fork: %r");
378 		case 0:
379 			break;
380 		default:
381 			exits(0);
382 		}
383 
384 	snprint(aserve, sizeof aserve, "%s", serve);
385 	afd = announce(aserve, adir);
386 	if(afd < 0)
387 		sysfatal("%s: %r\n", aserve);
388 	syslog(0, LOG, "ANNOUNCE %s", aserve);
389 	for(;;){
390 		if((lcfd = listen(adir, ldir)) < 0)
391 			exits("can't listen");
392 		switch(rfork(RFPROC|RFFDG|RFNOWAIT)){
393 		case -1:
394 			fprint(2, "secstore forking: %r\n");
395 			close(lcfd);
396 			break;
397 		case 0:
398 			/* "/lib/ndb/common.radius does not exist" if db set before fork */
399 			db = ndbopen(dbpath=unsharp("#9/ndb/auth"));
400 			if(db == 0)
401 				syslog(0, LOG, "no ndb/auth");
402 			db2 = ndbopen(0);
403 			if(db2 == 0)
404 				syslog(0, LOG, "no ndb/local");
405 			db = ndbcat(db, db2);
406 			if((dfd = accept(lcfd, ldir)) < 0)
407 				exits("can't accept");
408 			alarm(30*60*1000); 	/* 30 min */
409 			remote = remoteIP(ldir);
410 			syslog(0, LOG, "secstore from %s", remote);
411 			free(remote);
412 			dologin(dfd, S, forceSTA);
413 			exits(nil);
414 		default:
415 			close(lcfd);
416 			break;
417 		}
418 	}
419 }
420