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-rw-r--r--src/lib/libc/net/rcmd.c538
1 files changed, 162 insertions, 376 deletions
diff --git a/src/lib/libc/net/rcmd.c b/src/lib/libc/net/rcmd.c
index e0310031b0..d566e0ca4c 100644
--- a/src/lib/libc/net/rcmd.c
+++ b/src/lib/libc/net/rcmd.c
@@ -1,6 +1,5 @@
1/* $NetBSD: rcmd.c,v 1.12 1995/06/03 22:33:34 mycroft Exp $ */
2
3/* 1/*
2 * Copyright (c) 1995, 1996, 1998 Theo de Raadt. All rights reserved.
4 * Copyright (c) 1983, 1993, 1994 3 * Copyright (c) 1983, 1993, 1994
5 * The Regents of the University of California. All rights reserved. 4 * The Regents of the University of California. All rights reserved.
6 * 5 *
@@ -12,11 +11,7 @@
12 * 2. Redistributions in binary form must reproduce the above copyright 11 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the 12 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution. 13 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software 14 * 3. Neither the name of the University nor the names of its contributors
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software 15 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission. 16 * without specific prior written permission.
22 * 17 *
@@ -33,14 +28,6 @@
33 * SUCH DAMAGE. 28 * SUCH DAMAGE.
34 */ 29 */
35 30
36#if defined(LIBC_SCCS) && !defined(lint)
37#if 0
38static char sccsid[] = "@(#)rcmd.c 8.3 (Berkeley) 3/26/94";
39#else
40static char *rcsid = "$NetBSD: rcmd.c,v 1.12 1995/06/03 22:33:34 mycroft Exp $";
41#endif
42#endif /* LIBC_SCCS and not lint */
43
44#include <sys/param.h> 31#include <sys/param.h>
45#include <sys/socket.h> 32#include <sys/socket.h>
46#include <sys/stat.h> 33#include <sys/stat.h>
@@ -57,35 +44,77 @@ static char *rcsid = "$NetBSD: rcmd.c,v 1.12 1995/06/03 22:33:34 mycroft Exp $";
57#include <stdio.h> 44#include <stdio.h>
58#include <ctype.h> 45#include <ctype.h>
59#include <string.h> 46#include <string.h>
47#include <syslog.h>
48#include <stdlib.h>
60 49
61int __ivaliduser __P((FILE *, u_long, const char *, const char *)); 50int
62static int __icheckhost __P((u_long, const char *)); 51rcmd(char **ahost, int rport, const char *locuser, const char *remuser,
52 const char *cmd, int *fd2p)
53{
54 return rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
55}
63 56
64int 57int
65rcmd(ahost, rport, locuser, remuser, cmd, fd2p) 58rcmd_af(char **ahost, int porta, const char *locuser, const char *remuser,
66 char **ahost; 59 const char *cmd, int *fd2p, int af)
67 u_short rport;
68 const char *locuser, *remuser, *cmd;
69 int *fd2p;
70{ 60{
71 struct hostent *hp; 61 static char hbuf[MAXHOSTNAMELEN];
72 struct sockaddr_in sin, from; 62 char pbuf[NI_MAXSERV];
73 fd_set reads; 63 struct addrinfo hints, *res, *r;
74 long oldmask; 64 int error;
65 struct sockaddr_storage from;
66 fd_set *readsp = NULL;
67 sigset_t oldmask, mask;
75 pid_t pid; 68 pid_t pid;
76 int s, lport, timo; 69 int s, lport, timo;
77 char c; 70 char c, *p;
71 int refused;
72 in_port_t rport = porta;
73
74 /* call rcmdsh() with specified remote shell if appropriate. */
75 if (!issetugid() && (p = getenv("RSH")) && *p) {
76 struct servent *sp = getservbyname("shell", "tcp");
77
78 if (sp && sp->s_port == rport)
79 return (rcmdsh(ahost, rport, locuser, remuser,
80 cmd, p));
81 }
82
83 /* use rsh(1) if non-root and remote port is shell. */
84 if (geteuid()) {
85 struct servent *sp = getservbyname("shell", "tcp");
86
87 if (sp && sp->s_port == rport)
88 return (rcmdsh(ahost, rport, locuser, remuser,
89 cmd, NULL));
90 }
78 91
79 pid = getpid(); 92 pid = getpid();
80 hp = gethostbyname(*ahost); 93 snprintf(pbuf, sizeof(pbuf), "%u", ntohs(rport));
81 if (hp == NULL) { 94 memset(&hints, 0, sizeof(hints));
82 herror(*ahost); 95 hints.ai_family = af;
96 hints.ai_socktype = SOCK_STREAM;
97 hints.ai_flags = AI_CANONNAME;
98 error = getaddrinfo(*ahost, pbuf, &hints, &res);
99 if (error) {
100#if 0
101 warnx("%s: %s", *ahost, gai_strerror(error));
102#endif
83 return (-1); 103 return (-1);
84 } 104 }
85 *ahost = hp->h_name; 105 if (res->ai_canonname) {
86 oldmask = sigblock(sigmask(SIGURG)); 106 strlcpy(hbuf, res->ai_canonname, sizeof(hbuf));
107 *ahost = hbuf;
108 } else
109 ; /*XXX*/
110
111 r = res;
112 refused = 0;
113 sigemptyset(&mask);
114 sigaddset(&mask, SIGURG);
115 sigprocmask(SIG_BLOCK, &mask, &oldmask);
87 for (timo = 1, lport = IPPORT_RESERVED - 1;;) { 116 for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
88 s = rresvport(&lport); 117 s = rresvport_af(&lport, r->ai_family);
89 if (s < 0) { 118 if (s < 0) {
90 if (errno == EAGAIN) 119 if (errno == EAGAIN)
91 (void)fprintf(stderr, 120 (void)fprintf(stderr,
@@ -93,54 +122,84 @@ rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
93 else 122 else
94 (void)fprintf(stderr, "rcmd: socket: %s\n", 123 (void)fprintf(stderr, "rcmd: socket: %s\n",
95 strerror(errno)); 124 strerror(errno));
96 sigsetmask(oldmask); 125 if (r->ai_next) {
97 return (-1); 126 r = r->ai_next;
127 continue;
128 } else {
129 sigprocmask(SIG_SETMASK, &oldmask, NULL);
130 freeaddrinfo(res);
131 return (-1);
132 }
98 } 133 }
99 fcntl(s, F_SETOWN, pid); 134 fcntl(s, F_SETOWN, pid);
100 sin.sin_len = sizeof(struct sockaddr_in); 135 if (connect(s, r->ai_addr, r->ai_addrlen) >= 0)
101 sin.sin_family = hp->h_addrtype;
102 sin.sin_port = rport;
103 bcopy(hp->h_addr_list[0], &sin.sin_addr, hp->h_length);
104 if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
105 break; 136 break;
106 (void)close(s); 137 (void)close(s);
107 if (errno == EADDRINUSE) { 138 if (errno == EADDRINUSE) {
108 lport--; 139 lport--;
109 continue; 140 continue;
110 } 141 }
111 if (errno == ECONNREFUSED && timo <= 16) { 142 if (errno == ECONNREFUSED)
112 (void)sleep(timo); 143 refused++;
113 timo *= 2; 144 if (r->ai_next) {
114 continue;
115 }
116 if (hp->h_addr_list[1] != NULL) {
117 int oerrno = errno; 145 int oerrno = errno;
118 146 char hbuf[NI_MAXHOST];
119 (void)fprintf(stderr, "connect to address %s: ", 147 const int niflags = NI_NUMERICHOST;
120 inet_ntoa(sin.sin_addr)); 148
149 hbuf[0] = '\0';
150 if (getnameinfo(r->ai_addr, r->ai_addrlen,
151 hbuf, sizeof(hbuf), NULL, 0, niflags) != 0)
152 strlcpy(hbuf, "(invalid)", sizeof hbuf);
153 (void)fprintf(stderr, "connect to address %s: ", hbuf);
121 errno = oerrno; 154 errno = oerrno;
122 perror(0); 155 perror(0);
123 hp->h_addr_list++; 156 r = r->ai_next;
124 bcopy(hp->h_addr_list[0], &sin.sin_addr, hp->h_length); 157 hbuf[0] = '\0';
125 (void)fprintf(stderr, "Trying %s...\n", 158 if (getnameinfo(r->ai_addr, r->ai_addrlen,
126 inet_ntoa(sin.sin_addr)); 159 hbuf, sizeof(hbuf), NULL, 0, niflags) != 0)
160 strlcpy(hbuf, "(invalid)", sizeof hbuf);
161 (void)fprintf(stderr, "Trying %s...\n", hbuf);
127 continue; 162 continue;
128 } 163 }
129 (void)fprintf(stderr, "%s: %s\n", hp->h_name, strerror(errno)); 164 if (refused && timo <= 16) {
130 sigsetmask(oldmask); 165 (void)sleep(timo);
166 timo *= 2;
167 r = res;
168 refused = 0;
169 continue;
170 }
171 (void)fprintf(stderr, "%s: %s\n", res->ai_canonname,
172 strerror(errno));
173 sigprocmask(SIG_SETMASK, &oldmask, NULL);
174 freeaddrinfo(res);
131 return (-1); 175 return (-1);
132 } 176 }
177 /* given "af" can be PF_UNSPEC, we need the real af for "s" */
178 af = r->ai_family;
179 freeaddrinfo(res);
180#if 0
181 /*
182 * try to rresvport() to the same port. This will make rresvport()
183 * fail it's first bind, resulting in it choosing a random port.
184 */
133 lport--; 185 lport--;
186#endif
134 if (fd2p == 0) { 187 if (fd2p == 0) {
135 write(s, "", 1); 188 write(s, "", 1);
136 lport = 0; 189 lport = 0;
137 } else { 190 } else {
138 char num[8]; 191 char num[8];
139 int s2 = rresvport(&lport), s3; 192 int s2 = rresvport_af(&lport, af), s3;
140 int len = sizeof(from); 193 socklen_t len = sizeof(from);
194 int fdssize = howmany(MAX(s, s2)+1, NFDBITS) * sizeof(fd_mask);
141 195
142 if (s2 < 0) 196 if (s2 < 0)
143 goto bad; 197 goto bad;
198 readsp = (fd_set *)malloc(fdssize);
199 if (readsp == NULL) {
200 close(s2);
201 goto bad;
202 }
144 listen(s2, 1); 203 listen(s2, 1);
145 (void)snprintf(num, sizeof(num), "%d", lport); 204 (void)snprintf(num, sizeof(num), "%d", lport);
146 if (write(s, num, strlen(num)+1) != strlen(num)+1) { 205 if (write(s, num, strlen(num)+1) != strlen(num)+1) {
@@ -150,12 +209,13 @@ rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
150 (void)close(s2); 209 (void)close(s2);
151 goto bad; 210 goto bad;
152 } 211 }
153 FD_ZERO(&reads); 212again:
154 FD_SET(s, &reads); 213 bzero(readsp, fdssize);
155 FD_SET(s2, &reads); 214 FD_SET(s, readsp);
215 FD_SET(s2, readsp);
156 errno = 0; 216 errno = 0;
157 if (select(MAX(s, s2) + 1, &reads, 0, 0, 0) < 1 || 217 if (select(MAX(s, s2) + 1, readsp, 0, 0, 0) < 1 ||
158 !FD_ISSET(s2, &reads)) { 218 !FD_ISSET(s2, readsp)) {
159 if (errno != 0) 219 if (errno != 0)
160 (void)fprintf(stderr, 220 (void)fprintf(stderr,
161 "rcmd: select (setting up stderr): %s\n", 221 "rcmd: select (setting up stderr): %s\n",
@@ -167,21 +227,48 @@ rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
167 goto bad; 227 goto bad;
168 } 228 }
169 s3 = accept(s2, (struct sockaddr *)&from, &len); 229 s3 = accept(s2, (struct sockaddr *)&from, &len);
170 (void)close(s2);
171 if (s3 < 0) { 230 if (s3 < 0) {
172 (void)fprintf(stderr, 231 (void)fprintf(stderr,
173 "rcmd: accept: %s\n", strerror(errno)); 232 "rcmd: accept: %s\n", strerror(errno));
174 lport = 0; 233 lport = 0;
234 close(s2);
175 goto bad; 235 goto bad;
176 } 236 }
237
238 /*
239 * XXX careful for ftp bounce attacks. If discovered, shut them
240 * down and check for the real auxiliary channel to connect.
241 */
242 switch (from.ss_family) {
243 case AF_INET:
244 case AF_INET6:
245 if (getnameinfo((struct sockaddr *)&from, len,
246 NULL, 0, num, sizeof(num), NI_NUMERICSERV) == 0 &&
247 atoi(num) != 20) {
248 break;
249 }
250 close(s3);
251 goto again;
252 default:
253 break;
254 }
255 (void)close(s2);
256
177 *fd2p = s3; 257 *fd2p = s3;
178 from.sin_port = ntohs(from.sin_port); 258 switch (from.ss_family) {
179 if (from.sin_family != AF_INET || 259 case AF_INET:
180 from.sin_port >= IPPORT_RESERVED || 260 case AF_INET6:
181 from.sin_port < IPPORT_RESERVED / 2) { 261 if (getnameinfo((struct sockaddr *)&from, len,
182 (void)fprintf(stderr, 262 NULL, 0, num, sizeof(num), NI_NUMERICSERV) != 0 ||
183 "socket: protocol failure in circuit setup.\n"); 263 (atoi(num) >= IPPORT_RESERVED ||
184 goto bad2; 264 atoi(num) < IPPORT_RESERVED / 2)) {
265 (void)fprintf(stderr,
266 "socket: protocol failure in circuit setup.\n");
267 goto bad2;
268 }
269 break;
270 default:
271 break;
185 } 272 }
186 } 273 }
187 (void)write(s, locuser, strlen(locuser)+1); 274 (void)write(s, locuser, strlen(locuser)+1);
@@ -200,318 +287,17 @@ rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
200 } 287 }
201 goto bad2; 288 goto bad2;
202 } 289 }
203 sigsetmask(oldmask); 290 sigprocmask(SIG_SETMASK, &oldmask, NULL);
291 free(readsp);
204 return (s); 292 return (s);
205bad2: 293bad2:
206 if (lport) 294 if (lport)
207 (void)close(*fd2p); 295 (void)close(*fd2p);
208bad: 296bad:
297 if (readsp)
298 free(readsp);
209 (void)close(s); 299 (void)close(s);
210 sigsetmask(oldmask); 300 sigprocmask(SIG_SETMASK, &oldmask, NULL);
211 return (-1);
212}
213
214int
215rresvport(alport)
216 int *alport;
217{
218 struct sockaddr_in sin;
219 int s;
220
221 sin.sin_len = sizeof(struct sockaddr_in);
222 sin.sin_family = AF_INET;
223 sin.sin_addr.s_addr = INADDR_ANY;
224 s = socket(AF_INET, SOCK_STREAM, 0);
225 if (s < 0)
226 return (-1);
227 for (;;) {
228 sin.sin_port = htons((u_short)*alport);
229 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
230 return (s);
231 if (errno != EADDRINUSE) {
232 (void)close(s);
233 return (-1);
234 }
235 (*alport)--;
236 if (*alport == IPPORT_RESERVED/2) {
237 (void)close(s);
238 errno = EAGAIN; /* close */
239 return (-1);
240 }
241 }
242}
243
244int __check_rhosts_file = 1;
245char *__rcmd_errstr;
246
247int
248ruserok(rhost, superuser, ruser, luser)
249 const char *rhost, *ruser, *luser;
250 int superuser;
251{
252 struct hostent *hp;
253 char **ap;
254 int i;
255#define MAXADDRS 35
256 u_long addrs[MAXADDRS + 1];
257
258 if ((hp = gethostbyname(rhost)) == NULL)
259 return (-1);
260 for (i = 0, ap = hp->h_addr_list; *ap && i < MAXADDRS; ++ap, ++i)
261 bcopy(*ap, &addrs[i], sizeof(addrs[i]));
262 addrs[i] = 0;
263
264 for (i = 0; i < MAXADDRS && addrs[i]; i++)
265 if (iruserok(addrs[i], superuser, ruser, luser) == 0)
266 return (0);
267 return (-1);
268}
269
270/*
271 * New .rhosts strategy: We are passed an ip address. We spin through
272 * hosts.equiv and .rhosts looking for a match. When the .rhosts only
273 * has ip addresses, we don't have to trust a nameserver. When it
274 * contains hostnames, we spin through the list of addresses the nameserver
275 * gives us and look for a match.
276 *
277 * Returns 0 if ok, -1 if not ok.
278 */
279int
280iruserok(raddr, superuser, ruser, luser)
281 u_long raddr;
282 int superuser;
283 const char *ruser, *luser;
284{
285 register char *cp;
286 struct stat sbuf;
287 struct passwd *pwd;
288 FILE *hostf;
289 uid_t uid;
290 int first;
291 char pbuf[MAXPATHLEN];
292
293 first = 1;
294 hostf = superuser ? NULL : fopen(_PATH_HEQUIV, "r");
295again:
296 if (hostf) {
297 if (__ivaliduser(hostf, raddr, luser, ruser) == 0) {
298 (void)fclose(hostf);
299 return (0);
300 }
301 (void)fclose(hostf);
302 }
303 if (first == 1 && (__check_rhosts_file || superuser)) {
304 first = 0;
305 if ((pwd = getpwnam(luser)) == NULL)
306 return (-1);
307 (void)strcpy(pbuf, pwd->pw_dir);
308 (void)strcat(pbuf, "/.rhosts");
309
310 /*
311 * Change effective uid while opening .rhosts. If root and
312 * reading an NFS mounted file system, can't read files that
313 * are protected read/write owner only.
314 */
315 uid = geteuid();
316 (void)seteuid(pwd->pw_uid);
317 hostf = fopen(pbuf, "r");
318 (void)seteuid(uid);
319
320 if (hostf == NULL)
321 return (-1);
322 /*
323 * If not a regular file, or is owned by someone other than
324 * user or root or if writeable by anyone but the owner, quit.
325 */
326 cp = NULL;
327 if (lstat(pbuf, &sbuf) < 0)
328 cp = ".rhosts lstat failed";
329 else if (!S_ISREG(sbuf.st_mode))
330 cp = ".rhosts not regular file";
331 else if (fstat(fileno(hostf), &sbuf) < 0)
332 cp = ".rhosts fstat failed";
333 else if (sbuf.st_uid && sbuf.st_uid != pwd->pw_uid)
334 cp = "bad .rhosts owner";
335 else if (sbuf.st_mode & (S_IWGRP|S_IWOTH))
336 cp = ".rhosts writeable by other than owner";
337 /* If there were any problems, quit. */
338 if (cp) {
339 __rcmd_errstr = cp;
340 (void)fclose(hostf);
341 return (-1);
342 }
343 goto again;
344 }
345 return (-1); 301 return (-1);
346} 302}
347 303
348/*
349 * XXX
350 * Don't make static, used by lpd(8).
351 *
352 * Returns 0 if ok, -1 if not ok.
353 */
354int
355__ivaliduser(hostf, raddr, luser, ruser)
356 FILE *hostf;
357 u_long raddr;
358 const char *luser, *ruser;
359{
360 register char *user, *p;
361 int ch;
362 char buf[MAXHOSTNAMELEN + 128]; /* host + login */
363 const char *auser, *ahost;
364 int hostok, userok;
365 char rhost[MAXHOSTNAMELEN];
366 struct hostent *hp;
367 char domain[MAXHOSTNAMELEN];
368
369 getdomainname(domain, sizeof(domain));
370
371 while (fgets(buf, sizeof(buf), hostf)) {
372 p = buf;
373 /* Skip lines that are too long. */
374 if (strchr(p, '\n') == NULL) {
375 while ((ch = getc(hostf)) != '\n' && ch != EOF);
376 continue;
377 }
378 while (*p != '\n' && *p != ' ' && *p != '\t' && *p != '\0') {
379 *p = isupper(*p) ? tolower(*p) : *p;
380 p++;
381 }
382 if (*p == ' ' || *p == '\t') {
383 *p++ = '\0';
384 while (*p == ' ' || *p == '\t')
385 p++;
386 user = p;
387 while (*p != '\n' && *p != ' ' &&
388 *p != '\t' && *p != '\0')
389 p++;
390 } else
391 user = p;
392 *p = '\0';
393
394 if (p == buf)
395 continue;
396
397 auser = *user ? user : luser;
398 ahost = buf;
399
400 if ((hp = gethostbyaddr((char *) &raddr,
401 sizeof(raddr), AF_INET)) == NULL) {
402 abort();
403 return -1;
404 }
405 (void) strncpy(rhost, hp->h_name, sizeof(rhost));
406 rhost[sizeof(rhost) - 1] = '\0';
407
408 if (ahost[0] == '+')
409 switch (ahost[1]) {
410 case '\0':
411 hostok = 1;
412 break;
413
414 case '@':
415 hostok = innetgr(&ahost[2], rhost, NULL,
416 domain);
417 break;
418
419 default:
420 hostok = __icheckhost(raddr, &ahost[1]);
421 break;
422 }
423 else if (ahost[0] == '-')
424 switch (ahost[1]) {
425 case '\0':
426 hostok = -1;
427 break;
428
429 case '@':
430 hostok = -innetgr(&ahost[2], rhost, NULL,
431 domain);
432 break;
433
434 default:
435 hostok = -__icheckhost(raddr, &ahost[1]);
436 break;
437 }
438 else
439 hostok = __icheckhost(raddr, ahost);
440
441
442 if (auser[0] == '+')
443 switch (auser[1]) {
444 case '\0':
445 userok = 1;
446 break;
447
448 case '@':
449 userok = innetgr(&auser[2], NULL, ruser,
450 domain);
451 break;
452
453 default:
454 userok = strcmp(ruser, &auser[1]) == 0;
455 break;
456 }
457 else if (auser[0] == '-')
458 switch (auser[1]) {
459 case '\0':
460 userok = -1;
461 break;
462
463 case '@':
464 userok = -innetgr(&auser[2], NULL, ruser,
465 domain);
466 break;
467
468 default:
469 userok = -(strcmp(ruser, &auser[1]) == 0);
470 break;
471 }
472 else
473 userok = strcmp(ruser, auser) == 0;
474
475 /* Check if one component did not match */
476 if (hostok == 0 || userok == 0)
477 continue;
478
479 /* Check if we got a forbidden pair */
480 if (userok == -1 || hostok == -1)
481 return -1;
482
483 /* Check if we got a valid pair */
484 if (hostok == 1 && userok == 1)
485 return 0;
486 }
487 return -1;
488}
489
490/*
491 * Returns "true" if match, 0 if no match.
492 */
493static int
494__icheckhost(raddr, lhost)
495 u_long raddr;
496 const char *lhost;
497{
498 register struct hostent *hp;
499 register u_long laddr;
500 register char **pp;
501
502 /* Try for raw ip address first. */
503 if (isdigit(*lhost) && (long)(laddr = inet_addr(lhost)) != -1)
504 return (raddr == laddr);
505
506 /* Better be a hostname. */
507 if ((hp = gethostbyname(lhost)) == NULL)
508 return (0);
509
510 /* Spin through ip addresses. */
511 for (pp = hp->h_addr_list; *pp; ++pp)
512 if (!bcmp(&raddr, *pp, sizeof(u_long)))
513 return (1);
514
515 /* No match. */
516 return (0);
517}
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