Commit | Line | Data |
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1d1ccf4f MW |
1 | /* -*-c-*- |
2 | * | |
3 | * Make programs use Unix-domain sockets instead of IP | |
4 | * | |
5 | * (c) 2008 Straylight/Edgeware | |
6 | */ | |
7 | ||
8 | /*----- Licensing notice --------------------------------------------------* | |
9 | * | |
10 | * This file is part of the preload-hacks package. | |
11 | * | |
12 | * Preload-hacks are free software; you can redistribute it and/or modify | |
13 | * them under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2 of the License, or (at | |
15 | * your option) any later version. | |
16 | * | |
de6df72d MW |
17 | * Preload-hacks are distributed in the hope that it will be useful, but |
18 | * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY | |
19 | * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
20 | * for more details. | |
1d1ccf4f MW |
21 | * |
22 | * You should have received a copy of the GNU General Public License along | |
de6df72d MW |
23 | * with preload-hacks; if not, write to the Free Software Foundation, Inc., |
24 | * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
1d1ccf4f MW |
25 | */ |
26 | ||
e4976bb0 | 27 | #define _GNU_SOURCE |
28 | #undef sun | |
29 | #undef SUN | |
30 | #define DEBUG | |
31 | ||
1d1ccf4f MW |
32 | /*----- Header files ------------------------------------------------------*/ |
33 | ||
9314b85a | 34 | #include <assert.h> |
e4976bb0 | 35 | #include <ctype.h> |
36 | #include <errno.h> | |
9314b85a | 37 | #include <stddef.h> |
e4976bb0 | 38 | #include <stdio.h> |
39 | #include <stdlib.h> | |
40 | ||
41 | #include <unistd.h> | |
42 | #include <dirent.h> | |
43 | #include <dlfcn.h> | |
44 | #include <fcntl.h> | |
45 | #include <pwd.h> | |
46 | ||
47 | #include <sys/ioctl.h> | |
48 | #include <sys/socket.h> | |
49 | #include <sys/stat.h> | |
50 | #include <sys/un.h> | |
51 | ||
52 | #include <netinet/in.h> | |
53 | #include <arpa/inet.h> | |
54 | #include <netinet/tcp.h> | |
55 | #include <netinet/udp.h> | |
9f1396d9 | 56 | #include <ifaddrs.h> |
9314b85a | 57 | #include <netdb.h> |
e4976bb0 | 58 | |
1d1ccf4f MW |
59 | /*----- Data structures ---------------------------------------------------*/ |
60 | ||
61 | enum { UNUSED, STALE, USED }; /* Unix socket status values */ | |
62 | enum { WANT_FRESH, WANT_EXISTING }; /* Socket address dispositions */ | |
63 | enum { DENY, ALLOW }; /* ACL verdicts */ | |
64 | ||
2a06ea0b | 65 | static int address_families[] = { AF_INET, AF_INET6, -1 }; |
9314b85a MW |
66 | |
67 | #define ADDRBUFSZ 64 | |
68 | ||
69 | /* Address representations. */ | |
70 | typedef union ipaddr { | |
71 | struct in_addr v4; | |
2a06ea0b | 72 | struct in6_addr v6; |
9314b85a MW |
73 | } ipaddr; |
74 | ||
75 | /* Convenient socket address hacking. */ | |
76 | typedef union address { | |
77 | struct sockaddr sa; | |
78 | struct sockaddr_in sin; | |
2a06ea0b | 79 | struct sockaddr_in6 sin6; |
9314b85a MW |
80 | } address; |
81 | ||
1d1ccf4f | 82 | /* Access control list nodes */ |
e4976bb0 | 83 | typedef struct aclnode { |
84 | struct aclnode *next; | |
85 | int act; | |
9314b85a MW |
86 | int af; |
87 | ipaddr minaddr, maxaddr; | |
e4976bb0 | 88 | unsigned short minport, maxport; |
89 | } aclnode; | |
90 | ||
1d1ccf4f | 91 | /* Local address records */ |
9314b85a MW |
92 | typedef struct full_ipaddr { |
93 | int af; | |
94 | ipaddr addr; | |
95 | } full_ipaddr; | |
2a06ea0b | 96 | #define MAX_LOCAL_IPADDRS 64 |
9314b85a | 97 | static full_ipaddr local_ipaddrs[MAX_LOCAL_IPADDRS]; |
e4976bb0 | 98 | static int n_local_ipaddrs; |
99 | ||
1d1ccf4f | 100 | /* General configuration */ |
e4976bb0 | 101 | static uid_t uid; |
102 | static char *sockdir = 0; | |
103 | static int debug = 0; | |
f6049fdd | 104 | static unsigned minautoport = 16384, maxautoport = 65536; |
e4976bb0 | 105 | |
1d1ccf4f | 106 | /* Access control lists */ |
e4976bb0 | 107 | static aclnode *bind_real, **bind_tail = &bind_real; |
108 | static aclnode *connect_real, **connect_tail = &connect_real; | |
109 | ||
1d1ccf4f | 110 | /*----- Import the real versions of functions -----------------------------*/ |
e4976bb0 | 111 | |
1d1ccf4f | 112 | /* The list of functions to immport. */ |
e4976bb0 | 113 | #define IMPORTS(_) \ |
114 | _(socket, int, (int, int, int)) \ | |
115 | _(socketpair, int, (int, int, int, int *)) \ | |
116 | _(connect, int, (int, const struct sockaddr *, socklen_t)) \ | |
117 | _(bind, int, (int, const struct sockaddr *, socklen_t)) \ | |
118 | _(accept, int, (int, struct sockaddr *, socklen_t *)) \ | |
119 | _(getsockname, int, (int, struct sockaddr *, socklen_t *)) \ | |
120 | _(getpeername, int, (int, struct sockaddr *, socklen_t *)) \ | |
121 | _(getsockopt, int, (int, int, int, void *, socklen_t *)) \ | |
122 | _(setsockopt, int, (int, int, int, const void *, socklen_t)) \ | |
123 | _(sendto, ssize_t, (int, const void *buf, size_t, int, \ | |
124 | const struct sockaddr *to, socklen_t tolen)) \ | |
125 | _(recvfrom, ssize_t, (int, void *buf, size_t, int, \ | |
7d769c69 | 126 | struct sockaddr *from, socklen_t *fromlen)) \ |
e4976bb0 | 127 | _(sendmsg, ssize_t, (int, const struct msghdr *, int)) \ |
9fb8e5c9 | 128 | _(recvmsg, ssize_t, (int, struct msghdr *, int)) |
e4976bb0 | 129 | |
1d1ccf4f | 130 | /* Function pointers to set up. */ |
e4976bb0 | 131 | #define DECL(imp, ret, args) static ret (*real_##imp) args; |
132 | IMPORTS(DECL) | |
133 | #undef DECL | |
134 | ||
1d1ccf4f | 135 | /* Import the system calls. */ |
e4976bb0 | 136 | static void import(void) |
137 | { | |
138 | #define IMPORT(imp, ret, args) \ | |
139 | real_##imp = (ret (*)args)dlsym(RTLD_NEXT, #imp); | |
140 | IMPORTS(IMPORT) | |
141 | #undef IMPORT | |
142 | } | |
143 | ||
1d1ccf4f | 144 | /*----- Utilities ---------------------------------------------------------*/ |
e4976bb0 | 145 | |
1d1ccf4f | 146 | /* Socket address casts */ |
e4976bb0 | 147 | #define SA(sa) ((struct sockaddr *)(sa)) |
148 | #define SIN(sa) ((struct sockaddr_in *)(sa)) | |
2a06ea0b | 149 | #define SIN6(sa) ((struct sockaddr_in6 *)(sa)) |
e4976bb0 | 150 | #define SUN(sa) ((struct sockaddr_un *)(sa)) |
151 | ||
1d1ccf4f | 152 | /* Raw bytes */ |
e4976bb0 | 153 | #define UC(ch) ((unsigned char)(ch)) |
154 | ||
1d1ccf4f | 155 | /* Memory allocation */ |
e4976bb0 | 156 | #define NEW(x) ((x) = xmalloc(sizeof(*x))) |
157 | #define NEWV(x, n) ((x) = xmalloc(sizeof(*x) * (n))) | |
158 | ||
1d1ccf4f | 159 | /* Debugging */ |
e4976bb0 | 160 | #ifdef DEBUG |
161 | # define D(body) { if (debug) { body } } | |
162 | #else | |
163 | # define D(body) ; | |
164 | #endif | |
165 | ||
1d1ccf4f | 166 | /* Preservation of error status */ |
e4976bb0 | 167 | #define PRESERVING_ERRNO(body) do { \ |
168 | int _err = errno; { body } errno = _err; \ | |
169 | } while (0) | |
170 | ||
1d1ccf4f | 171 | /* Allocate N bytes of memory; abort on failure. */ |
e4976bb0 | 172 | static void *xmalloc(size_t n) |
173 | { | |
174 | void *p; | |
175 | if (!n) return (0); | |
3ef1fec9 | 176 | if ((p = malloc(n)) == 0) { perror("malloc"); exit(127); } |
e4976bb0 | 177 | return (p); |
178 | } | |
179 | ||
1d1ccf4f | 180 | /* Allocate a copy of the null-terminated string P; abort on failure. */ |
e4976bb0 | 181 | static char *xstrdup(const char *p) |
182 | { | |
183 | size_t n = strlen(p) + 1; | |
184 | char *q = xmalloc(n); | |
185 | memcpy(q, p, n); | |
186 | return (q); | |
187 | } | |
9314b85a MW |
188 | |
189 | /*----- Address-type hacking ----------------------------------------------*/ | |
190 | ||
191 | /* If M is a simple mask, i.e., consists of a sequence of zero bits followed | |
192 | * by a sequence of one bits, then return the length of the latter sequence | |
193 | * (which may be zero); otherwise return -1. | |
194 | */ | |
195 | static int simple_mask_length(unsigned long m) | |
196 | { | |
197 | int n = 0; | |
198 | ||
199 | while (m & 1) { n++; m >>= 1; } | |
200 | return (m ? -1 : n); | |
201 | } | |
202 | ||
203 | /* Answer whether AF is an interesting address family. */ | |
204 | static int family_known_p(int af) | |
205 | { | |
206 | switch (af) { | |
207 | case AF_INET: | |
2a06ea0b | 208 | case AF_INET6: |
9314b85a MW |
209 | return (1); |
210 | default: | |
211 | return (0); | |
212 | } | |
213 | } | |
214 | ||
215 | /* Return the socket address length for address family AF. */ | |
216 | static socklen_t family_socklen(int af) | |
217 | { | |
218 | switch (af) { | |
219 | case AF_INET: return (sizeof(struct sockaddr_in)); | |
2a06ea0b | 220 | case AF_INET6: return (sizeof(struct sockaddr_in6)); |
9314b85a MW |
221 | default: abort(); |
222 | } | |
223 | } | |
224 | ||
225 | /* Return the width of addresses of kind AF. */ | |
226 | static int address_width(int af) | |
227 | { | |
228 | switch (af) { | |
229 | case AF_INET: return 32; | |
2a06ea0b | 230 | case AF_INET6: return 128; |
9314b85a MW |
231 | default: abort(); |
232 | } | |
233 | } | |
234 | ||
235 | /* If addresses A and B share a common prefix then return its length; | |
236 | * otherwise return -1. | |
237 | */ | |
238 | static int common_prefix_length(int af, const ipaddr *a, const ipaddr *b) | |
239 | { | |
240 | switch (af) { | |
241 | case AF_INET: { | |
242 | unsigned long aa = ntohl(a->v4.s_addr), bb = ntohl(b->v4.s_addr); | |
243 | unsigned long m = aa^bb; | |
244 | if ((aa&m) == 0 && (bb&m) == m) return (32 - simple_mask_length(m)); | |
245 | else return (-1); | |
246 | } break; | |
2a06ea0b MW |
247 | case AF_INET6: { |
248 | const uint8_t *aa = a->v6.s6_addr, *bb = b->v6.s6_addr; | |
249 | unsigned m; | |
250 | unsigned n; | |
251 | int i; | |
252 | ||
253 | for (i = 0; i < 16 && aa[i] == bb[i]; i++); | |
254 | n = 8*i; | |
255 | if (i < 16) { | |
256 | m = aa[i]^bb[i]; | |
257 | if ((aa[i]&m) != 0 || (bb[i]&m) != m) return (-1); | |
258 | n += 8 - simple_mask_length(m); | |
259 | for (i++; i < 16; i++) | |
260 | if (aa[i] || bb[i] != 0xff) return (-1); | |
261 | } | |
262 | return (n); | |
263 | } break; | |
9314b85a MW |
264 | default: |
265 | abort(); | |
266 | } | |
267 | } | |
268 | ||
269 | /* Extract the port number (in host byte-order) from SA. */ | |
270 | static int port_from_sockaddr(const struct sockaddr *sa) | |
271 | { | |
272 | switch (sa->sa_family) { | |
273 | case AF_INET: return (ntohs(SIN(sa)->sin_port)); | |
2a06ea0b | 274 | case AF_INET6: return (ntohs(SIN6(sa)->sin6_port)); |
9314b85a MW |
275 | default: abort(); |
276 | } | |
277 | } | |
278 | ||
279 | /* Store the port number PORT (in host byte-order) in SA. */ | |
280 | static void port_to_sockaddr(struct sockaddr *sa, int port) | |
281 | { | |
282 | switch (sa->sa_family) { | |
283 | case AF_INET: SIN(sa)->sin_port = htons(port); break; | |
2a06ea0b | 284 | case AF_INET6: SIN6(sa)->sin6_port = htons(port); break; |
9314b85a MW |
285 | default: abort(); |
286 | } | |
287 | } | |
10cee633 | 288 | |
9314b85a MW |
289 | /* Extract the address part from SA and store it in A. */ |
290 | static void ipaddr_from_sockaddr(ipaddr *a, const struct sockaddr *sa) | |
291 | { | |
292 | switch (sa->sa_family) { | |
293 | case AF_INET: a->v4 = SIN(sa)->sin_addr; break; | |
2a06ea0b | 294 | case AF_INET6: a->v6 = SIN6(sa)->sin6_addr; break; |
9314b85a MW |
295 | default: abort(); |
296 | } | |
297 | } | |
298 | ||
299 | /* Copy a whole socket address about. */ | |
300 | static void copy_sockaddr(struct sockaddr *sa_dst, | |
301 | const struct sockaddr *sa_src) | |
302 | { memcpy(sa_dst, sa_src, family_socklen(sa_src->sa_family)); } | |
303 | ||
304 | /* Answer whether two addresses are equal. */ | |
305 | static int ipaddr_equal_p(int af, const ipaddr *a, const ipaddr *b) | |
306 | { | |
307 | switch (af) { | |
308 | case AF_INET: return (a->v4.s_addr == b->v4.s_addr); | |
2a06ea0b | 309 | case AF_INET6: return (memcmp(a->v6.s6_addr, b->v6.s6_addr, 16) == 0); |
9314b85a MW |
310 | default: abort(); |
311 | } | |
312 | } | |
313 | ||
314 | /* Answer whether the address part of SA is between A and B (inclusive). We | |
315 | * assume that SA has the correct address family. | |
316 | */ | |
317 | static int sockaddr_in_range_p(const struct sockaddr *sa, | |
318 | const ipaddr *a, const ipaddr *b) | |
319 | { | |
320 | switch (sa->sa_family) { | |
321 | case AF_INET: { | |
322 | unsigned long addr = ntohl(SIN(sa)->sin_addr.s_addr); | |
323 | return (ntohl(a->v4.s_addr) <= addr && | |
324 | addr <= ntohl(b->v4.s_addr)); | |
325 | } break; | |
2a06ea0b MW |
326 | case AF_INET6: { |
327 | const uint8_t *ss = SIN6(sa)->sin6_addr.s6_addr; | |
328 | const uint8_t *aa = a->v6.s6_addr, *bb = b->v6.s6_addr; | |
329 | int h = 1, l = 1; | |
330 | int i; | |
331 | ||
332 | for (i = 0; h && l && i < 16; i++, ss++, aa++, bb++) { | |
333 | if (*ss < *aa || *bb < *ss) return (0); | |
334 | if (*aa < *ss) l = 0; | |
335 | if (*ss < *bb) h = 0; | |
336 | } | |
337 | return (1); | |
338 | } break; | |
9314b85a MW |
339 | default: |
340 | abort(); | |
341 | } | |
342 | } | |
343 | ||
344 | /* Fill in SA with the appropriate wildcard address. */ | |
345 | static void wildcard_address(int af, struct sockaddr *sa) | |
346 | { | |
347 | switch (af) { | |
348 | case AF_INET: { | |
349 | struct sockaddr_in *sin = SIN(sa); | |
350 | memset(sin, 0, sizeof(*sin)); | |
351 | sin->sin_family = AF_INET; | |
352 | sin->sin_port = 0; | |
353 | sin->sin_addr.s_addr = INADDR_ANY; | |
354 | } break; | |
2a06ea0b MW |
355 | case AF_INET6: { |
356 | struct sockaddr_in6 *sin6 = SIN6(sa); | |
dc2b0a44 | 357 | memset(sin6, 0, sizeof(*sin6)); |
2a06ea0b MW |
358 | sin6->sin6_family = AF_INET6; |
359 | sin6->sin6_port = 0; | |
360 | sin6->sin6_addr = in6addr_any; | |
361 | sin6->sin6_scope_id = 0; | |
362 | sin6->sin6_flowinfo = 0; | |
363 | } break; | |
9314b85a MW |
364 | default: |
365 | abort(); | |
366 | } | |
367 | } | |
368 | ||
369 | /* Mask the address A, forcing all but the top PLEN bits to zero or one | |
370 | * according to HIGHP. | |
371 | */ | |
372 | static void mask_address(int af, ipaddr *a, int plen, int highp) | |
373 | { | |
374 | switch (af) { | |
375 | case AF_INET: { | |
376 | unsigned long addr = ntohl(a->v4.s_addr); | |
377 | unsigned long mask = plen ? ~0ul << (32 - plen) : 0; | |
378 | addr &= mask; | |
379 | if (highp) addr |= ~mask; | |
380 | a->v4.s_addr = htonl(addr & 0xffffffff); | |
381 | } break; | |
2a06ea0b MW |
382 | case AF_INET6: { |
383 | int i = plen/8; | |
384 | unsigned m = (0xff << (8 - plen%8)) & 0xff; | |
385 | unsigned s = highp ? 0xff : 0; | |
386 | if (m) { | |
387 | a->v6.s6_addr[i] = (a->v6.s6_addr[i] & m) | (s & ~m); | |
388 | i++; | |
389 | } | |
390 | for (; i < 16; i++) a->v6.s6_addr[i] = s; | |
391 | } break; | |
9314b85a MW |
392 | default: |
393 | abort(); | |
394 | } | |
395 | } | |
396 | ||
397 | /* Write a presentation form of SA to BUF, a buffer of length SZ. LEN is the | |
398 | * address length; if it's zero, look it up based on the address family. | |
399 | * Return a pointer to the string (which might, in an emergency, be a static | |
400 | * string rather than your buffer). | |
401 | */ | |
402 | static char *present_sockaddr(const struct sockaddr *sa, socklen_t len, | |
403 | char *buf, size_t sz) | |
404 | { | |
405 | #define WANT(n_) do { if (sz < (n_)) goto nospace; } while (0) | |
406 | #define PUTC(c_) do { *buf++ = (c_); sz--; } while (0) | |
407 | ||
408 | if (!sz) return "<no-space-in-buffer>"; | |
409 | if (!len) len = family_socklen(sa->sa_family); | |
410 | ||
411 | switch (sa->sa_family) { | |
412 | case AF_UNIX: { | |
413 | struct sockaddr_un *sun = SUN(sa); | |
414 | char *p = sun->sun_path; | |
415 | size_t n = len - offsetof(struct sockaddr_un, sun_path); | |
416 | ||
417 | assert(n); | |
418 | if (*p == 0) { | |
419 | WANT(1); PUTC('@'); | |
420 | p++; n--; | |
421 | while (n) { | |
422 | switch (*p) { | |
423 | case 0: WANT(2); PUTC('\\'); PUTC('0'); break; | |
424 | case '\a': WANT(2); PUTC('\\'); PUTC('a'); break; | |
425 | case '\n': WANT(2); PUTC('\\'); PUTC('n'); break; | |
426 | case '\r': WANT(2); PUTC('\\'); PUTC('r'); break; | |
427 | case '\t': WANT(2); PUTC('\\'); PUTC('t'); break; | |
428 | case '\v': WANT(2); PUTC('\\'); PUTC('v'); break; | |
429 | case '\\': WANT(2); PUTC('\\'); PUTC('\\'); break; | |
430 | default: | |
431 | if (*p > ' ' && *p <= '~') | |
432 | { WANT(1); PUTC(*p); } | |
433 | else { | |
434 | WANT(4); PUTC('\\'); PUTC('x'); | |
435 | PUTC((*p >> 4)&0xf); PUTC((*p >> 0)&0xf); | |
436 | } | |
437 | break; | |
438 | } | |
439 | p++; n--; | |
440 | } | |
441 | } else { | |
442 | if (*p != '/') { WANT(2); PUTC('.'); PUTC('/'); } | |
443 | while (n && *p) { WANT(1); PUTC(*p); p++; n--; } | |
444 | } | |
445 | WANT(1); PUTC(0); | |
446 | } break; | |
2a06ea0b | 447 | case AF_INET: case AF_INET6: { |
9314b85a MW |
448 | char addrbuf[NI_MAXHOST], portbuf[NI_MAXSERV]; |
449 | int err = getnameinfo(sa, len, | |
450 | addrbuf, sizeof(addrbuf), | |
451 | portbuf, sizeof(portbuf), | |
452 | NI_NUMERICHOST | NI_NUMERICSERV); | |
453 | assert(!err); | |
454 | snprintf(buf, sz, strchr(addrbuf, ':') ? "[%s]:%s" : "%s:%s", | |
455 | addrbuf, portbuf); | |
456 | } break; | |
457 | default: | |
458 | snprintf(buf, sz, "<unknown-address-family %d>", sa->sa_family); | |
459 | break; | |
460 | } | |
461 | return (buf); | |
462 | ||
463 | nospace: | |
464 | buf[sz - 1] = 0; | |
465 | return (buf); | |
466 | } | |
467 | ||
468 | /* Guess the family of a textual socket address. */ | |
469 | static int guess_address_family(const char *p) | |
2a06ea0b | 470 | { return (strchr(p, ':') ? AF_INET6 : AF_INET); } |
9314b85a MW |
471 | |
472 | /* Parse a socket address P and write the result to SA. */ | |
473 | static int parse_sockaddr(struct sockaddr *sa, const char *p) | |
474 | { | |
475 | char buf[ADDRBUFSZ]; | |
476 | char *q; | |
477 | struct addrinfo *ai, ai_hint = { 0 }; | |
478 | ||
479 | if (strlen(p) >= sizeof(buf) - 1) return (-1); | |
480 | strcpy(buf, p); p = buf; | |
481 | if (*p != '[') { | |
482 | if ((q = strchr(p, ':')) == 0) return (-1); | |
483 | *q++ = 0; | |
484 | } else { | |
485 | p++; | |
486 | if ((q = strchr(p, ']')) == 0) return (-1); | |
487 | *q++ = 0; | |
488 | if (*q != ':') return (-1); | |
489 | q++; | |
490 | } | |
491 | ||
492 | ai_hint.ai_family = AF_UNSPEC; | |
493 | ai_hint.ai_socktype = SOCK_DGRAM; | |
494 | ai_hint.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV; | |
495 | if (getaddrinfo(p, q, &ai_hint, &ai)) return (-1); | |
496 | memcpy(sa, ai->ai_addr, ai->ai_addrlen); | |
497 | freeaddrinfo(ai); | |
498 | return (0); | |
499 | } | |
500 | ||
1d1ccf4f | 501 | /*----- Access control lists ----------------------------------------------*/ |
e4976bb0 | 502 | |
503 | #ifdef DEBUG | |
504 | ||
1d1ccf4f | 505 | /* Write to standard error a description of the ACL node A. */ |
bb182ccf | 506 | static void dump_aclnode(const aclnode *a) |
e4976bb0 | 507 | { |
9314b85a MW |
508 | char buf[ADDRBUFSZ]; |
509 | const char *p; | |
510 | int plen; | |
e4976bb0 | 511 | |
e4976bb0 | 512 | fprintf(stderr, "noip: %c ", a->act ? '+' : '-'); |
9314b85a MW |
513 | plen = common_prefix_length(a->af, &a->minaddr, &a->maxaddr); |
514 | p = inet_ntop(a->af, &a->minaddr, buf, sizeof(buf)); | |
515 | fprintf(stderr, strchr(p, ':') ? "[%s]" : "%s", p); | |
516 | if (plen < 0) { | |
517 | p = inet_ntop(a->af, &a->maxaddr, buf, sizeof(buf)); | |
518 | fprintf(stderr, strchr(p, ':') ? "-[%s]" : "-%s", p); | |
519 | } else if (plen < address_width(a->af)) | |
520 | fprintf(stderr, "/%d", plen); | |
e4976bb0 | 521 | if (a->minport != 0 || a->maxport != 0xffff) { |
522 | fprintf(stderr, ":%u", (unsigned)a->minport); | |
523 | if (a->minport != a->maxport) | |
524 | fprintf(stderr, "-%u", (unsigned)a->maxport); | |
525 | } | |
526 | fputc('\n', stderr); | |
527 | } | |
528 | ||
bb182ccf | 529 | static void dump_acl(const aclnode *a) |
1d1ccf4f MW |
530 | { |
531 | int act = ALLOW; | |
532 | ||
533 | for (; a; a = a->next) { | |
534 | dump_aclnode(a); | |
535 | act = a->act; | |
536 | } | |
537 | fprintf(stderr, "noip: [default policy: %s]\n", | |
538 | act == ALLOW ? "DENY" : "ALLOW"); | |
539 | } | |
540 | ||
e4976bb0 | 541 | #endif |
542 | ||
9314b85a | 543 | /* Returns nonzero if the ACL A allows the socket address SA. */ |
bb182ccf | 544 | static int acl_allows_p(const aclnode *a, const struct sockaddr *sa) |
e4976bb0 | 545 | { |
9314b85a | 546 | unsigned short port = port_from_sockaddr(sa); |
e4976bb0 | 547 | int act = ALLOW; |
548 | ||
9314b85a MW |
549 | D({ char buf[ADDRBUFSZ]; |
550 | fprintf(stderr, "noip: check %s\n", | |
551 | present_sockaddr(sa, 0, buf, sizeof(buf))); }) | |
e4976bb0 | 552 | for (; a; a = a->next) { |
553 | D( dump_aclnode(a); ) | |
9314b85a | 554 | if (sockaddr_in_range_p(sa, &a->minaddr, &a->maxaddr) && |
e4976bb0 | 555 | a->minport <= port && port <= a->maxport) { |
556 | D( fprintf(stderr, "noip: aha! %s\n", a->act ? "ALLOW" : "DENY"); ) | |
557 | return (a->act); | |
558 | } | |
559 | act = a->act; | |
560 | } | |
561 | D( fprintf(stderr, "noip: nothing found: %s\n", act ? "DENY" : "ALLOW"); ) | |
562 | return (!act); | |
563 | } | |
564 | ||
1d1ccf4f | 565 | /*----- Socket address conversion -----------------------------------------*/ |
e4976bb0 | 566 | |
1d1ccf4f | 567 | /* Return a uniformly distributed integer between MIN and MAX inclusive. */ |
f6049fdd | 568 | static unsigned randrange(unsigned min, unsigned max) |
569 | { | |
570 | unsigned mask, i; | |
571 | ||
572 | /* It's so nice not to have to care about the quality of the generator | |
9314b85a MW |
573 | * much! |
574 | */ | |
f6049fdd | 575 | max -= min; |
576 | for (mask = 1; mask < max; mask = (mask << 1) | 1) | |
577 | ; | |
578 | do i = rand() & mask; while (i > max); | |
579 | return (i + min); | |
580 | } | |
581 | ||
1d1ccf4f MW |
582 | /* Return the status of Unix-domain socket address SUN. Returns: UNUSED if |
583 | * the socket doesn't exist; USED if the path refers to an active socket, or | |
584 | * isn't really a socket at all, or we can't tell without a careful search | |
585 | * and QUICKP is set; or STALE if the file refers to a socket which isn't | |
586 | * being used any more. | |
587 | */ | |
588 | static int unix_socket_status(struct sockaddr_un *sun, int quickp) | |
589 | { | |
590 | struct stat st; | |
591 | FILE *fp = 0; | |
592 | size_t len, n; | |
593 | int rc; | |
594 | char buf[256]; | |
595 | ||
596 | if (stat(sun->sun_path, &st)) | |
597 | return (errno == ENOENT ? UNUSED : USED); | |
598 | if (!S_ISSOCK(st.st_mode) || quickp) | |
599 | return (USED); | |
600 | rc = USED; | |
601 | if ((fp = fopen("/proc/net/unix", "r")) == 0) | |
602 | goto done; | |
72d85cdb | 603 | if (!fgets(buf, sizeof(buf), fp)) goto done; /* skip header */ |
1d1ccf4f MW |
604 | len = strlen(sun->sun_path); |
605 | while (fgets(buf, sizeof(buf), fp)) { | |
606 | n = strlen(buf); | |
607 | if (n >= len + 2 && buf[n - len - 2] == ' ' && buf[n - 1] == '\n' && | |
608 | memcmp(buf + n - len - 1, sun->sun_path, len) == 0) | |
609 | goto done; | |
610 | } | |
611 | if (ferror(fp)) | |
612 | goto done; | |
613 | rc = STALE; | |
614 | done: | |
615 | if (fp) fclose(fp); | |
616 | return (rc); | |
617 | } | |
618 | ||
9314b85a MW |
619 | /* Encode the Internet address SA as a Unix-domain address SUN. If WANT is |
620 | * WANT_FRESH, and SA's port number is zero, then we pick an arbitrary local | |
1d1ccf4f | 621 | * port. Otherwise we pick the port given. There's an unpleasant hack to |
9314b85a MW |
622 | * find servers bound to local wildcard addresses. Returns zero on success; |
623 | * -1 on failure. | |
1d1ccf4f | 624 | */ |
e4976bb0 | 625 | static int encode_inet_addr(struct sockaddr_un *sun, |
9314b85a | 626 | const struct sockaddr *sa, |
e4976bb0 | 627 | int want) |
628 | { | |
629 | int i; | |
3ef1fec9 | 630 | int desperatep = 0; |
9314b85a MW |
631 | address addr; |
632 | char buf[ADDRBUFSZ]; | |
e4976bb0 | 633 | int rc; |
634 | ||
9314b85a MW |
635 | D( fprintf(stderr, "noip: encode %s (%s)", |
636 | present_sockaddr(sa, 0, buf, sizeof(buf)), | |
e4976bb0 | 637 | want == WANT_EXISTING ? "EXISTING" : "FRESH"); ) |
638 | sun->sun_family = AF_UNIX; | |
9314b85a MW |
639 | if (port_from_sockaddr(sa) || want == WANT_EXISTING) { |
640 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
641 | present_sockaddr(sa, 0, buf, sizeof(buf))); | |
e4976bb0 | 642 | rc = unix_socket_status(sun, 0); |
643 | if (rc == STALE) unlink(sun->sun_path); | |
644 | if (rc != USED && want == WANT_EXISTING) { | |
9314b85a MW |
645 | wildcard_address(sa->sa_family, &addr.sa); |
646 | port_to_sockaddr(&addr.sa, port_from_sockaddr(sa)); | |
647 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
648 | present_sockaddr(&addr.sa, 0, buf, sizeof(buf))); | |
e4976bb0 | 649 | if (unix_socket_status(sun, 0) == STALE) unlink(sun->sun_path); |
650 | } | |
651 | } else { | |
9314b85a | 652 | copy_sockaddr(&addr.sa, sa); |
f6049fdd | 653 | for (i = 0; i < 10; i++) { |
9314b85a MW |
654 | port_to_sockaddr(&addr.sa, randrange(minautoport, maxautoport)); |
655 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
656 | present_sockaddr(&addr.sa, 0, buf, sizeof(buf))); | |
f6049fdd | 657 | if (unix_socket_status(sun, 1) == UNUSED) goto found; |
658 | } | |
3ef1fec9 | 659 | for (desperatep = 0; desperatep < 2; desperatep++) { |
f6049fdd | 660 | for (i = minautoport; i <= maxautoport; i++) { |
9314b85a MW |
661 | port_to_sockaddr(&addr.sa, i); |
662 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
663 | present_sockaddr(&addr.sa, 0, buf, sizeof(buf))); | |
3ef1fec9 | 664 | rc = unix_socket_status(sun, !desperatep); |
e4976bb0 | 665 | switch (rc) { |
666 | case STALE: unlink(sun->sun_path); | |
667 | case UNUSED: goto found; | |
668 | } | |
669 | } | |
670 | } | |
671 | errno = EADDRINUSE; | |
672 | D( fprintf(stderr, " -- can't resolve\n"); ) | |
673 | return (-1); | |
674 | found:; | |
675 | } | |
676 | D( fprintf(stderr, " -> `%s'\n", sun->sun_path); ) | |
677 | return (0); | |
678 | } | |
679 | ||
9314b85a | 680 | /* Decode the Unix address SUN to an Internet address SIN. If AF_HINT is |
c0876c8c MW |
681 | * nonzero, an empty address (indicative of an unbound Unix-domain socket) is |
682 | * translated to a wildcard Internet address of the appropriate family. | |
683 | * Returns zero on success; -1 on failure (e.g., it wasn't one of our | |
684 | * addresses). | |
00a98a8a | 685 | */ |
9314b85a | 686 | static int decode_inet_addr(struct sockaddr *sa, int af_hint, |
e4976bb0 | 687 | const struct sockaddr_un *sun, |
9314b85a | 688 | socklen_t len) |
e4976bb0 | 689 | { |
9314b85a | 690 | char buf[ADDRBUFSZ]; |
a2114371 | 691 | size_t n = strlen(sockdir), nn; |
9314b85a | 692 | address addr; |
e4976bb0 | 693 | |
9314b85a MW |
694 | if (!sa) sa = &addr.sa; |
695 | if (sun->sun_family != AF_UNIX) return (-1); | |
696 | if (len > sizeof(*sun)) return (-1); | |
697 | ((char *)sun)[len] = 0; | |
a2114371 | 698 | nn = strlen(sun->sun_path); |
9314b85a MW |
699 | D( fprintf(stderr, "noip: decode `%s'", sun->sun_path); ) |
700 | if (af_hint && !sun->sun_path[0]) { | |
701 | wildcard_address(af_hint, sa); | |
e4976bb0 | 702 | D( fprintf(stderr, " -- unbound socket\n"); ) |
703 | return (0); | |
704 | } | |
705 | if (nn < n + 1 || nn - n >= sizeof(buf) || sun->sun_path[n] != '/' || | |
706 | memcmp(sun->sun_path, sockdir, n) != 0) { | |
707 | D( fprintf(stderr, " -- not one of ours\n"); ) | |
708 | return (-1); | |
709 | } | |
9314b85a MW |
710 | if (parse_sockaddr(sa, sun->sun_path + n + 1)) return (-1); |
711 | D( fprintf(stderr, " -> %s\n", | |
712 | present_sockaddr(sa, 0, buf, sizeof(buf))); ) | |
e4976bb0 | 713 | return (0); |
714 | } | |
715 | ||
1d1ccf4f MW |
716 | /* SK is (or at least might be) a Unix-domain socket we created when an |
717 | * Internet socket was asked for. We've decided it should be an Internet | |
86134bfe MW |
718 | * socket after all, with family AF_HINT, so convert it. If TMP is not null, |
719 | * then don't replace the existing descriptor: store the new socket in *TMP | |
720 | * and return zero. | |
1d1ccf4f | 721 | */ |
86134bfe | 722 | static int fixup_real_ip_socket(int sk, int af_hint, int *tmp) |
e4976bb0 | 723 | { |
724 | int nsk; | |
725 | int type; | |
726 | int f, fd; | |
727 | struct sockaddr_un sun; | |
9314b85a | 728 | address addr; |
e4976bb0 | 729 | socklen_t len; |
730 | ||
731 | #define OPTS(_) \ | |
732 | _(DEBUG, int) \ | |
733 | _(REUSEADDR, int) \ | |
734 | _(DONTROUTE, int) \ | |
735 | _(BROADCAST, int) \ | |
736 | _(SNDBUF, int) \ | |
737 | _(RCVBUF, int) \ | |
738 | _(OOBINLINE, int) \ | |
739 | _(NO_CHECK, int) \ | |
740 | _(LINGER, struct linger) \ | |
741 | _(BSDCOMPAT, int) \ | |
742 | _(RCVLOWAT, int) \ | |
743 | _(RCVTIMEO, struct timeval) \ | |
744 | _(SNDTIMEO, struct timeval) | |
745 | ||
746 | len = sizeof(sun); | |
747 | if (real_getsockname(sk, SA(&sun), &len)) | |
748 | return (-1); | |
9314b85a | 749 | if (decode_inet_addr(&addr.sa, af_hint, &sun, len)) |
e4976bb0 | 750 | return (0); /* Not one of ours */ |
751 | len = sizeof(type); | |
752 | if (real_getsockopt(sk, SOL_SOCKET, SO_TYPE, &type, &len) < 0 || | |
9314b85a | 753 | (nsk = real_socket(addr.sa.sa_family, type, 0)) < 0) |
e4976bb0 | 754 | return (-1); |
755 | #define FIX(opt, ty) do { \ | |
756 | ty ov_; \ | |
757 | len = sizeof(ov_); \ | |
758 | if (real_getsockopt(sk, SOL_SOCKET, SO_##opt, &ov_, &len) < 0 || \ | |
759 | real_setsockopt(nsk, SOL_SOCKET, SO_##opt, &ov_, len)) { \ | |
9fb8e5c9 | 760 | close(nsk); \ |
e4976bb0 | 761 | return (-1); \ |
762 | } \ | |
763 | } while (0); | |
764 | OPTS(FIX) | |
765 | #undef FIX | |
86134bfe MW |
766 | if (tmp) |
767 | *tmp = nsk; | |
768 | else { | |
769 | if ((f = fcntl(sk, F_GETFL)) < 0 || | |
770 | (fd = fcntl(sk, F_GETFD)) < 0 || | |
771 | fcntl(nsk, F_SETFL, f) < 0 || | |
772 | dup2(nsk, sk) < 0) { | |
773 | close(nsk); | |
774 | return (-1); | |
775 | } | |
776 | unlink(sun.sun_path); | |
9fb8e5c9 | 777 | close(nsk); |
86134bfe MW |
778 | if (fcntl(sk, F_SETFD, fd) < 0) { |
779 | perror("noip: fixup_real_ip_socket F_SETFD"); | |
780 | abort(); | |
781 | } | |
e4976bb0 | 782 | } |
783 | return (0); | |
784 | } | |
785 | ||
1d1ccf4f | 786 | /* The socket SK is about to be used to communicate with the remote address |
9314b85a MW |
787 | * SA. Assign it a local address so that getpeername(2) does something |
788 | * useful. | |
1d1ccf4f | 789 | */ |
e4976bb0 | 790 | static int do_implicit_bind(int sk, const struct sockaddr **sa, |
791 | socklen_t *len, struct sockaddr_un *sun) | |
792 | { | |
9314b85a | 793 | address addr; |
e4976bb0 | 794 | socklen_t mylen = sizeof(*sun); |
795 | ||
9314b85a | 796 | if (acl_allows_p(connect_real, *sa)) { |
86134bfe | 797 | if (fixup_real_ip_socket(sk, (*sa)->sa_family, 0)) return (-1); |
e4976bb0 | 798 | } else { |
9314b85a | 799 | if (real_getsockname(sk, SA(sun), &mylen) < 0) return (-1); |
e4976bb0 | 800 | if (sun->sun_family == AF_UNIX) { |
801 | if (mylen < sizeof(*sun)) ((char *)sun)[mylen] = 0; | |
802 | if (!sun->sun_path[0]) { | |
9314b85a MW |
803 | wildcard_address((*sa)->sa_family, &addr.sa); |
804 | encode_inet_addr(sun, &addr.sa, WANT_FRESH); | |
805 | if (real_bind(sk, SA(sun), SUN_LEN(sun))) return (-1); | |
e4976bb0 | 806 | } |
9314b85a | 807 | encode_inet_addr(sun, *sa, WANT_EXISTING); |
e4976bb0 | 808 | *sa = SA(sun); |
809 | *len = SUN_LEN(sun); | |
810 | } | |
811 | } | |
812 | return (0); | |
813 | } | |
814 | ||
1d1ccf4f MW |
815 | /* We found the real address SA, with length LEN; if it's a Unix-domain |
816 | * address corresponding to a fake socket, convert it to cover up the | |
817 | * deception. Whatever happens, put the result at FAKE and store its length | |
818 | * at FAKELEN. | |
819 | */ | |
e4976bb0 | 820 | static void return_fake_name(struct sockaddr *sa, socklen_t len, |
821 | struct sockaddr *fake, socklen_t *fakelen) | |
822 | { | |
9314b85a | 823 | address addr; |
e4976bb0 | 824 | socklen_t alen; |
825 | ||
00a98a8a | 826 | if (sa->sa_family == AF_UNIX && |
9314b85a MW |
827 | !decode_inet_addr(&addr.sa, 0, SUN(sa), len)) { |
828 | sa = &addr.sa; | |
829 | len = family_socklen(addr.sa.sa_family); | |
e4976bb0 | 830 | } |
831 | alen = len; | |
9314b85a MW |
832 | if (len > *fakelen) len = *fakelen; |
833 | if (len > 0) memcpy(fake, sa, len); | |
e4976bb0 | 834 | *fakelen = alen; |
835 | } | |
836 | ||
1d1ccf4f | 837 | /*----- Configuration -----------------------------------------------------*/ |
e4976bb0 | 838 | |
1d1ccf4f | 839 | /* Return the process owner's home directory. */ |
e4976bb0 | 840 | static char *home(void) |
841 | { | |
842 | char *p; | |
843 | struct passwd *pw; | |
844 | ||
3ef1fec9 | 845 | if (getuid() == uid && |
846 | (p = getenv("HOME")) != 0) | |
847 | return (p); | |
848 | else if ((pw = getpwuid(uid)) != 0) | |
849 | return (pw->pw_dir); | |
850 | else | |
851 | return "/notexist"; | |
e4976bb0 | 852 | } |
853 | ||
1d1ccf4f | 854 | /* Return a good temporary directory to use. */ |
e4976bb0 | 855 | static char *tmpdir(void) |
856 | { | |
857 | char *p; | |
858 | ||
859 | if ((p = getenv("TMPDIR")) != 0) return (p); | |
860 | else if ((p = getenv("TMP")) != 0) return (p); | |
861 | else return ("/tmp"); | |
862 | } | |
863 | ||
1d1ccf4f | 864 | /* Return the user's name, or at least something distinctive. */ |
e4976bb0 | 865 | static char *user(void) |
866 | { | |
867 | static char buf[16]; | |
868 | char *p; | |
869 | struct passwd *pw; | |
870 | ||
871 | if ((p = getenv("USER")) != 0) return (p); | |
872 | else if ((p = getenv("LOGNAME")) != 0) return (p); | |
873 | else if ((pw = getpwuid(uid)) != 0) return (pw->pw_name); | |
874 | else { | |
875 | snprintf(buf, sizeof(buf), "uid-%lu", (unsigned long)uid); | |
876 | return (buf); | |
877 | } | |
878 | } | |
879 | ||
1d1ccf4f | 880 | /* Skip P over space characters. */ |
e4976bb0 | 881 | #define SKIPSPC do { while (*p && isspace(UC(*p))) p++; } while (0) |
1d1ccf4f MW |
882 | |
883 | /* Set Q to point to the next word following P, null-terminate it, and step P | |
884 | * past it. */ | |
e4976bb0 | 885 | #define NEXTWORD(q) do { \ |
886 | SKIPSPC; \ | |
887 | q = p; \ | |
888 | while (*p && !isspace(UC(*p))) p++; \ | |
889 | if (*p) *p++ = 0; \ | |
890 | } while (0) | |
1d1ccf4f MW |
891 | |
892 | /* Set Q to point to the next dotted-quad address, store the ending delimiter | |
893 | * in DEL, null-terminate it, and step P past it. */ | |
9314b85a MW |
894 | static void parse_nextaddr(char **pp, char **qq, int *del) |
895 | { | |
896 | char *p = *pp; | |
897 | ||
898 | SKIPSPC; | |
899 | if (*p == '[') { | |
900 | p++; SKIPSPC; | |
901 | *qq = p; | |
902 | p += strcspn(p, "]"); | |
903 | if (*p) *p++ = 0; | |
904 | *del = 0; | |
905 | } else { | |
906 | *qq = p; | |
907 | while (*p && (*p == '.' || isdigit(UC(*p)))) p++; | |
908 | *del = *p; | |
909 | if (*p) *p++ = 0; | |
910 | } | |
911 | *pp = p; | |
912 | } | |
1d1ccf4f MW |
913 | |
914 | /* Set Q to point to the next decimal number, store the ending delimiter in | |
915 | * DEL, null-terminate it, and step P past it. */ | |
e4976bb0 | 916 | #define NEXTNUMBER(q, del) do { \ |
917 | SKIPSPC; \ | |
918 | q = p; \ | |
919 | while (*p && isdigit(UC(*p))) p++; \ | |
920 | del = *p; \ | |
921 | if (*p) *p++ = 0; \ | |
922 | } while (0) | |
1d1ccf4f MW |
923 | |
924 | /* Push the character DEL back so we scan it again, unless it's zero | |
925 | * (end-of-file). */ | |
e4976bb0 | 926 | #define RESCAN(del) do { if (del) *--p = del; } while (0) |
1d1ccf4f MW |
927 | |
928 | /* Evaluate true if P is pointing to the word KW (and not some longer string | |
929 | * of which KW is a prefix). */ | |
930 | ||
e4976bb0 | 931 | #define KWMATCHP(kw) (strncmp(p, kw, sizeof(kw) - 1) == 0 && \ |
932 | !isalnum(UC(p[sizeof(kw) - 1])) && \ | |
933 | (p += sizeof(kw) - 1)) | |
9f82ba1f | 934 | |
1d1ccf4f MW |
935 | /* Parse a port list, starting at *PP. Port lists have the form |
936 | * [:LOW[-HIGH]]: if omitted, all ports are included; if HIGH is omitted, | |
937 | * it's as if HIGH = LOW. Store LOW in *MIN, HIGH in *MAX and set *PP to the | |
938 | * rest of the string. | |
939 | */ | |
e4976bb0 | 940 | static void parse_ports(char **pp, unsigned short *min, unsigned short *max) |
941 | { | |
942 | char *p = *pp, *q; | |
943 | int del; | |
944 | ||
945 | SKIPSPC; | |
f6049fdd | 946 | if (*p != ':') |
947 | { *min = 0; *max = 0xffff; } | |
948 | else { | |
e4976bb0 | 949 | p++; |
f6049fdd | 950 | NEXTNUMBER(q, del); *min = strtoul(q, 0, 0); RESCAN(del); |
e4976bb0 | 951 | SKIPSPC; |
f6049fdd | 952 | if (*p == '-') |
d83beb5c | 953 | { p++; NEXTNUMBER(q, del); *max = strtoul(q, 0, 0); RESCAN(del); } |
f6049fdd | 954 | else |
e4976bb0 | 955 | *max = *min; |
956 | } | |
957 | *pp = p; | |
958 | } | |
959 | ||
9314b85a MW |
960 | /* Make a new ACL node. ACT is the verdict; AF is the address family; |
961 | * MINADDR and MAXADDR are the ranges on IP addresses; MINPORT and MAXPORT | |
962 | * are the ranges on port numbers; TAIL is the list tail to attach the new | |
963 | * node to. | |
1d1ccf4f | 964 | */ |
e4976bb0 | 965 | #define ACLNODE(tail_, act_, \ |
9314b85a | 966 | af_, minaddr_, maxaddr_, minport_, maxport_) do { \ |
e4976bb0 | 967 | aclnode *a_; \ |
968 | NEW(a_); \ | |
9314b85a MW |
969 | a_->act = (act_); \ |
970 | a_->af = (af_); \ | |
971 | a_->minaddr = (minaddr_); a_->maxaddr = (maxaddr_); \ | |
972 | a_->minport = (minport_); a_->maxport = (maxport_); \ | |
e4976bb0 | 973 | *tail_ = a_; tail_ = &a_->next; \ |
974 | } while (0) | |
975 | ||
1d1ccf4f MW |
976 | /* Parse an ACL line. *PP points to the end of the line; *TAIL points to |
977 | * the list tail (i.e., the final link in the list). An ACL entry has the | |
978 | * form +|- [any | local | ADDR | ADDR - ADDR | ADDR/ADDR | ADDR/INT] PORTS | |
979 | * where PORTS is parsed by parse_ports above; an ACL line consists of a | |
980 | * comma-separated sequence of entries.. | |
981 | */ | |
e4976bb0 | 982 | static void parse_acl_line(char **pp, aclnode ***tail) |
983 | { | |
9314b85a | 984 | ipaddr minaddr, maxaddr; |
e4976bb0 | 985 | unsigned short minport, maxport; |
9314b85a | 986 | int i, af, n; |
e4976bb0 | 987 | int act; |
988 | int del; | |
989 | char *p = *pp; | |
990 | char *q; | |
991 | ||
a6d9626b | 992 | for (;;) { |
993 | SKIPSPC; | |
994 | if (*p == '+') act = ALLOW; | |
995 | else if (*p == '-') act = DENY; | |
996 | else goto bad; | |
e4976bb0 | 997 | |
a6d9626b | 998 | p++; |
999 | SKIPSPC; | |
1000 | if (KWMATCHP("any")) { | |
9314b85a MW |
1001 | parse_ports(&p, &minport, &maxport); |
1002 | for (i = 0; address_families[i] >= 0; i++) { | |
1003 | af = address_families[i]; | |
1004 | memset(&minaddr, 0, sizeof(minaddr)); | |
1005 | maxaddr = minaddr; mask_address(af, &maxaddr, 0, 1); | |
1006 | ACLNODE(*tail, act, af, minaddr, maxaddr, minport, maxport); | |
1007 | } | |
a6d9626b | 1008 | } else if (KWMATCHP("local")) { |
1009 | parse_ports(&p, &minport, &maxport); | |
9314b85a MW |
1010 | for (i = 0; address_families[i] >= 0; i++) { |
1011 | af = address_families[i]; | |
1012 | memset(&minaddr, 0, sizeof(minaddr)); | |
1013 | maxaddr = minaddr; mask_address(af, &maxaddr, 0, 1); | |
1014 | ACLNODE(*tail, act, af, minaddr, minaddr, minport, maxport); | |
1015 | ACLNODE(*tail, act, af, maxaddr, maxaddr, minport, maxport); | |
1016 | } | |
a6d9626b | 1017 | for (i = 0; i < n_local_ipaddrs; i++) { |
9314b85a MW |
1018 | ACLNODE(*tail, act, local_ipaddrs[i].af, |
1019 | local_ipaddrs[i].addr, local_ipaddrs[i].addr, | |
1020 | minport, maxport); | |
a6d9626b | 1021 | } |
e4976bb0 | 1022 | } else { |
9314b85a MW |
1023 | parse_nextaddr(&p, &q, &del); |
1024 | af = guess_address_family(q); | |
1025 | if (inet_pton(af, q, &minaddr) <= 0) goto bad; | |
1026 | RESCAN(del); | |
1027 | SKIPSPC; | |
1028 | if (*p == '-') { | |
1029 | p++; | |
1030 | parse_nextaddr(&p, &q, &del); | |
1031 | if (inet_pton(af, q, &maxaddr) <= 0) goto bad; | |
e4976bb0 | 1032 | RESCAN(del); |
9314b85a MW |
1033 | } else if (*p == '/') { |
1034 | p++; | |
1035 | NEXTNUMBER(q, del); | |
1036 | n = strtoul(q, 0, 0); | |
1037 | maxaddr = minaddr; | |
1038 | mask_address(af, &minaddr, n, 0); | |
1039 | mask_address(af, &maxaddr, n, 1); | |
1040 | } else | |
1041 | maxaddr = minaddr; | |
a6d9626b | 1042 | parse_ports(&p, &minport, &maxport); |
9314b85a | 1043 | ACLNODE(*tail, act, af, minaddr, maxaddr, minport, maxport); |
e4976bb0 | 1044 | } |
a6d9626b | 1045 | SKIPSPC; |
1046 | if (*p != ',') break; | |
1cce4a41 | 1047 | if (*p) p++; |
e4976bb0 | 1048 | } |
f797ea6d | 1049 | *pp = p; |
e4976bb0 | 1050 | return; |
1051 | ||
1052 | bad: | |
1053 | D( fprintf(stderr, "noip: bad acl spec (ignored)\n"); ) | |
1054 | return; | |
1055 | } | |
1056 | ||
1d1ccf4f | 1057 | /* Parse the autoports configuration directive. Syntax is MIN - MAX. */ |
f6049fdd | 1058 | static void parse_autoports(char **pp) |
1059 | { | |
1060 | char *p = *pp, *q; | |
1061 | unsigned x, y; | |
1062 | int del; | |
1063 | ||
1064 | SKIPSPC; | |
1065 | NEXTNUMBER(q, del); x = strtoul(q, 0, 0); RESCAN(del); | |
1066 | SKIPSPC; | |
1067 | if (*p != '-') goto bad; p++; | |
1068 | NEXTNUMBER(q, del); y = strtoul(q, 0, 0); RESCAN(del); | |
1069 | minautoport = x; maxautoport = y; | |
f797ea6d | 1070 | *pp = p; |
f6049fdd | 1071 | return; |
1072 | ||
1073 | bad: | |
1074 | D( fprintf(stderr, "bad port range (ignored)\n"); ) | |
1075 | return; | |
1076 | } | |
1077 | ||
1d1ccf4f MW |
1078 | /* Parse an ACL from an environment variable VAR, attaching it to the list |
1079 | * TAIL. */ | |
a6d9626b | 1080 | static void parse_acl_env(const char *var, aclnode ***tail) |
1081 | { | |
f6049fdd | 1082 | char *p, *q; |
a6d9626b | 1083 | |
1084 | if ((p = getenv(var)) != 0) { | |
f6049fdd | 1085 | p = q = xstrdup(p); |
1086 | parse_acl_line(&q, tail); | |
a6d9626b | 1087 | free(p); |
1088 | } | |
1089 | } | |
1090 | ||
1d1ccf4f | 1091 | /* Read the configuration from the config file and environment. */ |
e4976bb0 | 1092 | static void readconfig(void) |
1093 | { | |
1094 | FILE *fp; | |
1095 | char buf[1024]; | |
1096 | size_t n; | |
f6049fdd | 1097 | char *p, *q, *cmd; |
e4976bb0 | 1098 | |
a6d9626b | 1099 | parse_acl_env("NOIP_REALBIND_BEFORE", &bind_tail); |
1100 | parse_acl_env("NOIP_REALCONNECT_BEFORE", &connect_tail); | |
f6049fdd | 1101 | if ((p = getenv("NOIP_AUTOPORTS")) != 0) { |
1102 | p = q = xstrdup(p); | |
1103 | parse_autoports(&q); | |
1104 | free(p); | |
1105 | } | |
4ab301de | 1106 | if ((p = getenv("NOIP_CONFIG")) == 0) |
1107 | snprintf(p = buf, sizeof(buf), "%s/.noip", home()); | |
1108 | D( fprintf(stderr, "noip: config file: %s\n", p); ) | |
1109 | ||
1110 | if ((fp = fopen(p, "r")) == 0) { | |
1111 | D( fprintf(stderr, "noip: couldn't read config: %s\n", | |
1112 | strerror(errno)); ) | |
f6049fdd | 1113 | goto done; |
4ab301de | 1114 | } |
e4976bb0 | 1115 | while (fgets(buf, sizeof(buf), fp)) { |
1116 | n = strlen(buf); | |
1117 | p = buf; | |
1118 | ||
1119 | SKIPSPC; | |
1120 | if (!*p || *p == '#') continue; | |
1121 | while (n && isspace(UC(buf[n - 1]))) n--; | |
1122 | buf[n] = 0; | |
1123 | NEXTWORD(cmd); | |
1124 | SKIPSPC; | |
1125 | ||
1126 | if (strcmp(cmd, "socketdir") == 0) | |
1127 | sockdir = xstrdup(p); | |
1128 | else if (strcmp(cmd, "realbind") == 0) | |
1129 | parse_acl_line(&p, &bind_tail); | |
1130 | else if (strcmp(cmd, "realconnect") == 0) | |
1131 | parse_acl_line(&p, &connect_tail); | |
f6049fdd | 1132 | else if (strcmp(cmd, "autoports") == 0) |
1133 | parse_autoports(&p); | |
e4976bb0 | 1134 | else if (strcmp(cmd, "debug") == 0) |
1135 | debug = *p ? atoi(p) : 1; | |
1136 | else | |
1137 | D( fprintf(stderr, "noip: bad config command %s\n", cmd); ) | |
1138 | } | |
1139 | fclose(fp); | |
1140 | ||
1141 | done: | |
a6d9626b | 1142 | parse_acl_env("NOIP_REALBIND", &bind_tail); |
1143 | parse_acl_env("NOIP_REALCONNECT", &connect_tail); | |
1144 | parse_acl_env("NOIP_REALBIND_AFTER", &bind_tail); | |
1145 | parse_acl_env("NOIP_REALCONNECT_AFTER", &connect_tail); | |
e4976bb0 | 1146 | *bind_tail = 0; |
1147 | *connect_tail = 0; | |
a6d9626b | 1148 | if (!sockdir) sockdir = getenv("NOIP_SOCKETDIR"); |
e4976bb0 | 1149 | if (!sockdir) { |
1150 | snprintf(buf, sizeof(buf), "%s/noip-%s", tmpdir(), user()); | |
1151 | sockdir = xstrdup(buf); | |
1152 | } | |
3ef1fec9 | 1153 | D( fprintf(stderr, "noip: socketdir: %s\n", sockdir); |
f6049fdd | 1154 | fprintf(stderr, "noip: autoports: %u-%u\n", |
1155 | minautoport, maxautoport); | |
e4976bb0 | 1156 | fprintf(stderr, "noip: realbind acl:\n"); |
1157 | dump_acl(bind_real); | |
1158 | fprintf(stderr, "noip: realconnect acl:\n"); | |
1159 | dump_acl(connect_real); ) | |
1160 | } | |
1161 | ||
1d1ccf4f | 1162 | /*----- Overridden system calls -------------------------------------------*/ |
e4976bb0 | 1163 | |
1164 | int socket(int pf, int ty, int proto) | |
1165 | { | |
8ce11853 | 1166 | switch (pf) { |
9314b85a MW |
1167 | default: |
1168 | if (!family_known_p(pf)) { | |
1169 | errno = EAFNOSUPPORT; | |
1170 | return (-1); | |
1171 | } | |
8ce11853 MW |
1172 | pf = PF_UNIX; |
1173 | proto = 0; | |
1174 | case PF_UNIX: | |
41c50995 MW |
1175 | #ifdef PF_NETLINK |
1176 | case PF_NETLINK: | |
1177 | #endif | |
9314b85a | 1178 | return (real_socket(pf, ty, proto)); |
e4976bb0 | 1179 | } |
e4976bb0 | 1180 | } |
1181 | ||
1182 | int socketpair(int pf, int ty, int proto, int *sk) | |
1183 | { | |
17085e3f | 1184 | if (family_known_p(pf)) { |
e4976bb0 | 1185 | pf = PF_UNIX; |
1186 | proto = 0; | |
1187 | } | |
1188 | return (real_socketpair(pf, ty, proto, sk)); | |
1189 | } | |
1190 | ||
1191 | int bind(int sk, const struct sockaddr *sa, socklen_t len) | |
1192 | { | |
1193 | struct sockaddr_un sun; | |
1194 | ||
9314b85a | 1195 | if (family_known_p(sa->sa_family)) { |
e4976bb0 | 1196 | PRESERVING_ERRNO({ |
9314b85a | 1197 | if (acl_allows_p(bind_real, sa)) { |
86134bfe | 1198 | if (fixup_real_ip_socket(sk, sa->sa_family, 0)) |
e4976bb0 | 1199 | return (-1); |
1200 | } else { | |
9314b85a | 1201 | encode_inet_addr(&sun, sa, WANT_FRESH); |
e4976bb0 | 1202 | sa = SA(&sun); |
1203 | len = SUN_LEN(&sun); | |
1204 | } | |
1205 | }); | |
1206 | } | |
9314b85a | 1207 | return (real_bind(sk, sa, len)); |
e4976bb0 | 1208 | } |
1209 | ||
1210 | int connect(int sk, const struct sockaddr *sa, socklen_t len) | |
1211 | { | |
1212 | struct sockaddr_un sun; | |
53390eff | 1213 | int rc; |
e4976bb0 | 1214 | |
9314b85a MW |
1215 | if (!family_known_p(sa->sa_family)) |
1216 | rc = real_connect(sk, sa, len); | |
1217 | else { | |
1218 | PRESERVING_ERRNO({ | |
1219 | do_implicit_bind(sk, &sa, &len, &sun); | |
1220 | }); | |
1221 | rc = real_connect(sk, sa, len); | |
1222 | if (rc < 0) { | |
1223 | switch (errno) { | |
1224 | case ENOENT: errno = ECONNREFUSED; break; | |
6df6f816 | 1225 | } |
9314b85a | 1226 | } |
53390eff | 1227 | } |
9314b85a | 1228 | return (rc); |
e4976bb0 | 1229 | } |
1230 | ||
1231 | ssize_t sendto(int sk, const void *buf, size_t len, int flags, | |
1232 | const struct sockaddr *to, socklen_t tolen) | |
1233 | { | |
1234 | struct sockaddr_un sun; | |
1235 | ||
17085e3f | 1236 | if (to && family_known_p(to->sa_family)) { |
e4976bb0 | 1237 | PRESERVING_ERRNO({ |
1238 | do_implicit_bind(sk, &to, &tolen, &sun); | |
1239 | }); | |
1240 | } | |
9314b85a | 1241 | return (real_sendto(sk, buf, len, flags, to, tolen)); |
e4976bb0 | 1242 | } |
1243 | ||
1244 | ssize_t recvfrom(int sk, void *buf, size_t len, int flags, | |
1245 | struct sockaddr *from, socklen_t *fromlen) | |
1246 | { | |
1247 | char sabuf[1024]; | |
1248 | socklen_t mylen = sizeof(sabuf); | |
1249 | ssize_t n; | |
1250 | ||
1251 | if (!from) | |
1252 | return real_recvfrom(sk, buf, len, flags, 0, 0); | |
1253 | PRESERVING_ERRNO({ | |
1254 | n = real_recvfrom(sk, buf, len, flags, SA(sabuf), &mylen); | |
1255 | if (n < 0) | |
1256 | return (-1); | |
1257 | return_fake_name(SA(sabuf), mylen, from, fromlen); | |
1258 | }); | |
1259 | return (n); | |
1260 | } | |
1261 | ||
1262 | ssize_t sendmsg(int sk, const struct msghdr *msg, int flags) | |
1263 | { | |
1264 | struct sockaddr_un sun; | |
1265 | const struct sockaddr *sa; | |
1266 | struct msghdr mymsg; | |
1267 | ||
17085e3f | 1268 | if (msg->msg_name && family_known_p(SA(msg->msg_name)->sa_family)) { |
e4976bb0 | 1269 | PRESERVING_ERRNO({ |
1270 | sa = SA(msg->msg_name); | |
1271 | mymsg = *msg; | |
1272 | do_implicit_bind(sk, &sa, &mymsg.msg_namelen, &sun); | |
1273 | mymsg.msg_name = SA(sa); | |
1274 | msg = &mymsg; | |
1275 | }); | |
1276 | } | |
9314b85a | 1277 | return (real_sendmsg(sk, msg, flags)); |
e4976bb0 | 1278 | } |
1279 | ||
1280 | ssize_t recvmsg(int sk, struct msghdr *msg, int flags) | |
1281 | { | |
1282 | char sabuf[1024]; | |
1283 | struct sockaddr *sa; | |
1284 | socklen_t len; | |
1285 | ssize_t n; | |
1286 | ||
1287 | if (!msg->msg_name) | |
9314b85a | 1288 | return (real_recvmsg(sk, msg, flags)); |
e4976bb0 | 1289 | PRESERVING_ERRNO({ |
1290 | sa = SA(msg->msg_name); | |
1291 | len = msg->msg_namelen; | |
1292 | msg->msg_name = sabuf; | |
1293 | msg->msg_namelen = sizeof(sabuf); | |
1294 | n = real_recvmsg(sk, msg, flags); | |
1295 | if (n < 0) | |
1296 | return (-1); | |
1297 | return_fake_name(SA(sabuf), msg->msg_namelen, sa, &len); | |
1298 | msg->msg_name = sa; | |
1299 | msg->msg_namelen = len; | |
1300 | }); | |
1301 | return (n); | |
1302 | } | |
1303 | ||
1304 | int accept(int sk, struct sockaddr *sa, socklen_t *len) | |
1305 | { | |
1306 | char sabuf[1024]; | |
1307 | socklen_t mylen = sizeof(sabuf); | |
1308 | int nsk = real_accept(sk, SA(sabuf), &mylen); | |
1309 | ||
1310 | if (nsk < 0) | |
1311 | return (-1); | |
1312 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1313 | return (nsk); | |
1314 | } | |
1315 | ||
1316 | int getsockname(int sk, struct sockaddr *sa, socklen_t *len) | |
1317 | { | |
1318 | PRESERVING_ERRNO({ | |
1319 | char sabuf[1024]; | |
1320 | socklen_t mylen = sizeof(sabuf); | |
1321 | if (real_getsockname(sk, SA(sabuf), &mylen)) | |
1322 | return (-1); | |
1323 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1324 | }); | |
1325 | return (0); | |
1326 | } | |
1327 | ||
1328 | int getpeername(int sk, struct sockaddr *sa, socklen_t *len) | |
1329 | { | |
1330 | PRESERVING_ERRNO({ | |
1331 | char sabuf[1024]; | |
1332 | socklen_t mylen = sizeof(sabuf); | |
1333 | if (real_getpeername(sk, SA(sabuf), &mylen)) | |
1334 | return (-1); | |
1335 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1336 | }); | |
1337 | return (0); | |
1338 | } | |
1339 | ||
1340 | int getsockopt(int sk, int lev, int opt, void *p, socklen_t *len) | |
1341 | { | |
1342 | switch (lev) { | |
1343 | case SOL_IP: | |
1344 | case SOL_TCP: | |
1345 | case SOL_UDP: | |
1346 | if (*len > 0) | |
1347 | memset(p, 0, *len); | |
1348 | return (0); | |
1349 | } | |
9314b85a | 1350 | return (real_getsockopt(sk, lev, opt, p, len)); |
e4976bb0 | 1351 | } |
1352 | ||
1353 | int setsockopt(int sk, int lev, int opt, const void *p, socklen_t len) | |
1354 | { | |
1355 | switch (lev) { | |
1356 | case SOL_IP: | |
1357 | case SOL_TCP: | |
1358 | case SOL_UDP: | |
1359 | return (0); | |
1360 | } | |
1361 | switch (opt) { | |
1362 | case SO_BINDTODEVICE: | |
1363 | case SO_ATTACH_FILTER: | |
1364 | case SO_DETACH_FILTER: | |
1365 | return (0); | |
1366 | } | |
9314b85a | 1367 | return (real_setsockopt(sk, lev, opt, p, len)); |
e4976bb0 | 1368 | } |
1369 | ||
1d1ccf4f | 1370 | /*----- Initialization ----------------------------------------------------*/ |
e4976bb0 | 1371 | |
1d1ccf4f | 1372 | /* Clean up the socket directory, deleting stale sockets. */ |
e4976bb0 | 1373 | static void cleanup_sockdir(void) |
1374 | { | |
1375 | DIR *dir; | |
1376 | struct dirent *d; | |
9314b85a | 1377 | address addr; |
e4976bb0 | 1378 | struct sockaddr_un sun; |
3ef1fec9 | 1379 | struct stat st; |
e4976bb0 | 1380 | |
9314b85a | 1381 | if ((dir = opendir(sockdir)) == 0) return; |
4ab301de | 1382 | sun.sun_family = AF_UNIX; |
e4976bb0 | 1383 | while ((d = readdir(dir)) != 0) { |
1384 | if (d->d_name[0] == '.') continue; | |
1385 | snprintf(sun.sun_path, sizeof(sun.sun_path), | |
1386 | "%s/%s", sockdir, d->d_name); | |
9314b85a | 1387 | if (decode_inet_addr(&addr.sa, 0, &sun, SUN_LEN(&sun)) || |
3ef1fec9 | 1388 | stat(sun.sun_path, &st) || |
4ab301de | 1389 | !S_ISSOCK(st.st_mode)) { |
1390 | D( fprintf(stderr, "noip: ignoring unknown socketdir entry `%s'\n", | |
1391 | sun.sun_path); ) | |
3ef1fec9 | 1392 | continue; |
4ab301de | 1393 | } |
e4976bb0 | 1394 | if (unix_socket_status(&sun, 0) == STALE) { |
1395 | D( fprintf(stderr, "noip: clearing away stale socket %s\n", | |
1396 | d->d_name); ) | |
1397 | unlink(sun.sun_path); | |
1398 | } | |
1399 | } | |
1400 | closedir(dir); | |
1401 | } | |
1402 | ||
1d1ccf4f MW |
1403 | /* Find the addresses attached to local network interfaces, and remember them |
1404 | * in a table. | |
1405 | */ | |
e4976bb0 | 1406 | static void get_local_ipaddrs(void) |
1407 | { | |
9f1396d9 | 1408 | struct ifaddrs *ifa_head, *ifa; |
9314b85a | 1409 | ipaddr a; |
e4976bb0 | 1410 | int i; |
1411 | ||
9f1396d9 MW |
1412 | if (getifaddrs(&ifa_head)) { perror("getifaddrs"); return; } |
1413 | for (n_local_ipaddrs = 0, ifa = ifa_head; | |
1414 | n_local_ipaddrs < MAX_LOCAL_IPADDRS && ifa; | |
1415 | ifa = ifa->ifa_next) { | |
9314b85a | 1416 | if (!ifa->ifa_addr || !family_known_p(ifa->ifa_addr->sa_family)) |
e4976bb0 | 1417 | continue; |
9314b85a MW |
1418 | ipaddr_from_sockaddr(&a, ifa->ifa_addr); |
1419 | D({ char buf[ADDRBUFSZ]; | |
1420 | fprintf(stderr, "noip: local addr %s = %s", ifa->ifa_name, | |
1421 | inet_ntop(ifa->ifa_addr->sa_family, &a, | |
1422 | buf, sizeof(buf))); }) | |
9f1396d9 | 1423 | for (i = 0; i < n_local_ipaddrs; i++) { |
9314b85a MW |
1424 | if (ifa->ifa_addr->sa_family == local_ipaddrs[i].af && |
1425 | ipaddr_equal_p(local_ipaddrs[i].af, &a, &local_ipaddrs[i].addr)) { | |
9f1396d9 MW |
1426 | D( fprintf(stderr, " (duplicate)\n"); ) |
1427 | goto skip; | |
1428 | } | |
1429 | } | |
1430 | D( fprintf(stderr, "\n"); ) | |
9314b85a MW |
1431 | local_ipaddrs[n_local_ipaddrs].af = ifa->ifa_addr->sa_family; |
1432 | local_ipaddrs[n_local_ipaddrs].addr = a; | |
9f1396d9 MW |
1433 | n_local_ipaddrs++; |
1434 | skip:; | |
e4976bb0 | 1435 | } |
9f1396d9 | 1436 | freeifaddrs(ifa_head); |
e4976bb0 | 1437 | } |
1438 | ||
1d1ccf4f | 1439 | /* Print the given message to standard error. Avoids stdio. */ |
72d85cdb | 1440 | static void printerr(const char *p) |
65f3786c | 1441 | { if (write(STDERR_FILENO, p, strlen(p))) ; } |
3ef1fec9 | 1442 | |
1d1ccf4f | 1443 | /* Create the socket directory, being careful about permissions. */ |
3ef1fec9 | 1444 | static void create_sockdir(void) |
1445 | { | |
1446 | struct stat st; | |
1447 | ||
b514afdd | 1448 | if (lstat(sockdir, &st)) { |
3ef1fec9 | 1449 | if (errno == ENOENT) { |
1450 | if (mkdir(sockdir, 0700)) { | |
1451 | perror("noip: creating socketdir"); | |
1452 | exit(127); | |
1453 | } | |
b514afdd | 1454 | if (!lstat(sockdir, &st)) |
3ef1fec9 | 1455 | goto check; |
1456 | } | |
1457 | perror("noip: checking socketdir"); | |
1458 | exit(127); | |
1459 | } | |
1460 | check: | |
1461 | if (!S_ISDIR(st.st_mode)) { | |
1462 | printerr("noip: bad socketdir: not a directory\n"); | |
1463 | exit(127); | |
1464 | } | |
1465 | if (st.st_uid != uid) { | |
1466 | printerr("noip: bad socketdir: not owner\n"); | |
1467 | exit(127); | |
1468 | } | |
1469 | if (st.st_mode & 077) { | |
1470 | printerr("noip: bad socketdir: not private\n"); | |
1471 | exit(127); | |
1472 | } | |
1473 | } | |
1474 | ||
1d1ccf4f MW |
1475 | /* Initialization function. */ |
1476 | static void setup(void) __attribute__((constructor)); | |
e4976bb0 | 1477 | static void setup(void) |
1478 | { | |
1479 | PRESERVING_ERRNO({ | |
1480 | char *p; | |
1481 | ||
1482 | import(); | |
3ef1fec9 | 1483 | uid = geteuid(); |
e4976bb0 | 1484 | if ((p = getenv("NOIP_DEBUG")) && atoi(p)) |
1485 | debug = 1; | |
1486 | get_local_ipaddrs(); | |
1487 | readconfig(); | |
3ef1fec9 | 1488 | create_sockdir(); |
e4976bb0 | 1489 | cleanup_sockdir(); |
1490 | }); | |
1491 | } | |
1d1ccf4f MW |
1492 | |
1493 | /*----- That's all, folks -------------------------------------------------*/ |