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> | |
658c1774 | 37 | #include <stdarg.h> |
9314b85a | 38 | #include <stddef.h> |
e4976bb0 | 39 | #include <stdio.h> |
40 | #include <stdlib.h> | |
41 | ||
42 | #include <unistd.h> | |
43 | #include <dirent.h> | |
44 | #include <dlfcn.h> | |
45 | #include <fcntl.h> | |
46 | #include <pwd.h> | |
47 | ||
48 | #include <sys/ioctl.h> | |
49 | #include <sys/socket.h> | |
50 | #include <sys/stat.h> | |
51 | #include <sys/un.h> | |
52 | ||
53 | #include <netinet/in.h> | |
54 | #include <arpa/inet.h> | |
55 | #include <netinet/tcp.h> | |
56 | #include <netinet/udp.h> | |
9f1396d9 | 57 | #include <ifaddrs.h> |
9314b85a | 58 | #include <netdb.h> |
e4976bb0 | 59 | |
1d1ccf4f MW |
60 | /*----- Data structures ---------------------------------------------------*/ |
61 | ||
62 | enum { UNUSED, STALE, USED }; /* Unix socket status values */ | |
63 | enum { WANT_FRESH, WANT_EXISTING }; /* Socket address dispositions */ | |
64 | enum { DENY, ALLOW }; /* ACL verdicts */ | |
65 | ||
2a06ea0b | 66 | static int address_families[] = { AF_INET, AF_INET6, -1 }; |
9314b85a MW |
67 | |
68 | #define ADDRBUFSZ 64 | |
69 | ||
70 | /* Address representations. */ | |
71 | typedef union ipaddr { | |
72 | struct in_addr v4; | |
2a06ea0b | 73 | struct in6_addr v6; |
9314b85a MW |
74 | } ipaddr; |
75 | ||
76 | /* Convenient socket address hacking. */ | |
77 | typedef union address { | |
78 | struct sockaddr sa; | |
79 | struct sockaddr_in sin; | |
2a06ea0b | 80 | struct sockaddr_in6 sin6; |
9314b85a MW |
81 | } address; |
82 | ||
1d1ccf4f | 83 | /* Access control list nodes */ |
e4976bb0 | 84 | typedef struct aclnode { |
85 | struct aclnode *next; | |
86 | int act; | |
9314b85a MW |
87 | int af; |
88 | ipaddr minaddr, maxaddr; | |
e4976bb0 | 89 | unsigned short minport, maxport; |
90 | } aclnode; | |
91 | ||
1d1ccf4f | 92 | /* Local address records */ |
9314b85a MW |
93 | typedef struct full_ipaddr { |
94 | int af; | |
95 | ipaddr addr; | |
96 | } full_ipaddr; | |
2a06ea0b | 97 | #define MAX_LOCAL_IPADDRS 64 |
9314b85a | 98 | static full_ipaddr local_ipaddrs[MAX_LOCAL_IPADDRS]; |
e4976bb0 | 99 | static int n_local_ipaddrs; |
100 | ||
1d1ccf4f | 101 | /* General configuration */ |
e4976bb0 | 102 | static uid_t uid; |
103 | static char *sockdir = 0; | |
104 | static int debug = 0; | |
f6049fdd | 105 | static unsigned minautoport = 16384, maxautoport = 65536; |
e4976bb0 | 106 | |
1d1ccf4f | 107 | /* Access control lists */ |
e4976bb0 | 108 | static aclnode *bind_real, **bind_tail = &bind_real; |
109 | static aclnode *connect_real, **connect_tail = &connect_real; | |
110 | ||
1d1ccf4f | 111 | /*----- Import the real versions of functions -----------------------------*/ |
e4976bb0 | 112 | |
1d1ccf4f | 113 | /* The list of functions to immport. */ |
e4976bb0 | 114 | #define IMPORTS(_) \ |
115 | _(socket, int, (int, int, int)) \ | |
116 | _(socketpair, int, (int, int, int, int *)) \ | |
117 | _(connect, int, (int, const struct sockaddr *, socklen_t)) \ | |
118 | _(bind, int, (int, const struct sockaddr *, socklen_t)) \ | |
119 | _(accept, int, (int, struct sockaddr *, socklen_t *)) \ | |
120 | _(getsockname, int, (int, struct sockaddr *, socklen_t *)) \ | |
121 | _(getpeername, int, (int, struct sockaddr *, socklen_t *)) \ | |
122 | _(getsockopt, int, (int, int, int, void *, socklen_t *)) \ | |
123 | _(setsockopt, int, (int, int, int, const void *, socklen_t)) \ | |
124 | _(sendto, ssize_t, (int, const void *buf, size_t, int, \ | |
125 | const struct sockaddr *to, socklen_t tolen)) \ | |
126 | _(recvfrom, ssize_t, (int, void *buf, size_t, int, \ | |
7d769c69 | 127 | struct sockaddr *from, socklen_t *fromlen)) \ |
e4976bb0 | 128 | _(sendmsg, ssize_t, (int, const struct msghdr *, int)) \ |
658c1774 MW |
129 | _(recvmsg, ssize_t, (int, struct msghdr *, int)) \ |
130 | _(ioctl, int, (int, unsigned long, ...)) | |
e4976bb0 | 131 | |
1d1ccf4f | 132 | /* Function pointers to set up. */ |
e4976bb0 | 133 | #define DECL(imp, ret, args) static ret (*real_##imp) args; |
134 | IMPORTS(DECL) | |
135 | #undef DECL | |
136 | ||
1d1ccf4f | 137 | /* Import the system calls. */ |
e4976bb0 | 138 | static void import(void) |
139 | { | |
140 | #define IMPORT(imp, ret, args) \ | |
141 | real_##imp = (ret (*)args)dlsym(RTLD_NEXT, #imp); | |
142 | IMPORTS(IMPORT) | |
143 | #undef IMPORT | |
144 | } | |
145 | ||
1d1ccf4f | 146 | /*----- Utilities ---------------------------------------------------------*/ |
e4976bb0 | 147 | |
1d1ccf4f | 148 | /* Socket address casts */ |
e4976bb0 | 149 | #define SA(sa) ((struct sockaddr *)(sa)) |
150 | #define SIN(sa) ((struct sockaddr_in *)(sa)) | |
2a06ea0b | 151 | #define SIN6(sa) ((struct sockaddr_in6 *)(sa)) |
e4976bb0 | 152 | #define SUN(sa) ((struct sockaddr_un *)(sa)) |
153 | ||
1d1ccf4f | 154 | /* Raw bytes */ |
e4976bb0 | 155 | #define UC(ch) ((unsigned char)(ch)) |
156 | ||
1d1ccf4f | 157 | /* Memory allocation */ |
e4976bb0 | 158 | #define NEW(x) ((x) = xmalloc(sizeof(*x))) |
159 | #define NEWV(x, n) ((x) = xmalloc(sizeof(*x) * (n))) | |
160 | ||
1d1ccf4f | 161 | /* Debugging */ |
e4976bb0 | 162 | #ifdef DEBUG |
163 | # define D(body) { if (debug) { body } } | |
e397f0bd | 164 | # define Dpid pid_t pid = debug ? getpid() : -1 |
e4976bb0 | 165 | #else |
166 | # define D(body) ; | |
e397f0bd | 167 | # define Dpid |
e4976bb0 | 168 | #endif |
169 | ||
1d1ccf4f | 170 | /* Preservation of error status */ |
e4976bb0 | 171 | #define PRESERVING_ERRNO(body) do { \ |
172 | int _err = errno; { body } errno = _err; \ | |
173 | } while (0) | |
174 | ||
1d1ccf4f | 175 | /* Allocate N bytes of memory; abort on failure. */ |
e4976bb0 | 176 | static void *xmalloc(size_t n) |
177 | { | |
178 | void *p; | |
179 | if (!n) return (0); | |
3ef1fec9 | 180 | if ((p = malloc(n)) == 0) { perror("malloc"); exit(127); } |
e4976bb0 | 181 | return (p); |
182 | } | |
183 | ||
1d1ccf4f | 184 | /* Allocate a copy of the null-terminated string P; abort on failure. */ |
e4976bb0 | 185 | static char *xstrdup(const char *p) |
186 | { | |
187 | size_t n = strlen(p) + 1; | |
188 | char *q = xmalloc(n); | |
189 | memcpy(q, p, n); | |
190 | return (q); | |
191 | } | |
9314b85a MW |
192 | |
193 | /*----- Address-type hacking ----------------------------------------------*/ | |
194 | ||
195 | /* If M is a simple mask, i.e., consists of a sequence of zero bits followed | |
196 | * by a sequence of one bits, then return the length of the latter sequence | |
197 | * (which may be zero); otherwise return -1. | |
198 | */ | |
199 | static int simple_mask_length(unsigned long m) | |
200 | { | |
201 | int n = 0; | |
202 | ||
203 | while (m & 1) { n++; m >>= 1; } | |
204 | return (m ? -1 : n); | |
205 | } | |
206 | ||
207 | /* Answer whether AF is an interesting address family. */ | |
208 | static int family_known_p(int af) | |
209 | { | |
210 | switch (af) { | |
211 | case AF_INET: | |
2a06ea0b | 212 | case AF_INET6: |
9314b85a MW |
213 | return (1); |
214 | default: | |
215 | return (0); | |
216 | } | |
217 | } | |
218 | ||
219 | /* Return the socket address length for address family AF. */ | |
220 | static socklen_t family_socklen(int af) | |
221 | { | |
222 | switch (af) { | |
223 | case AF_INET: return (sizeof(struct sockaddr_in)); | |
2a06ea0b | 224 | case AF_INET6: return (sizeof(struct sockaddr_in6)); |
9314b85a MW |
225 | default: abort(); |
226 | } | |
227 | } | |
228 | ||
229 | /* Return the width of addresses of kind AF. */ | |
230 | static int address_width(int af) | |
231 | { | |
232 | switch (af) { | |
233 | case AF_INET: return 32; | |
2a06ea0b | 234 | case AF_INET6: return 128; |
9314b85a MW |
235 | default: abort(); |
236 | } | |
237 | } | |
238 | ||
239 | /* If addresses A and B share a common prefix then return its length; | |
240 | * otherwise return -1. | |
241 | */ | |
242 | static int common_prefix_length(int af, const ipaddr *a, const ipaddr *b) | |
243 | { | |
244 | switch (af) { | |
245 | case AF_INET: { | |
246 | unsigned long aa = ntohl(a->v4.s_addr), bb = ntohl(b->v4.s_addr); | |
247 | unsigned long m = aa^bb; | |
248 | if ((aa&m) == 0 && (bb&m) == m) return (32 - simple_mask_length(m)); | |
249 | else return (-1); | |
250 | } break; | |
2a06ea0b MW |
251 | case AF_INET6: { |
252 | const uint8_t *aa = a->v6.s6_addr, *bb = b->v6.s6_addr; | |
253 | unsigned m; | |
254 | unsigned n; | |
255 | int i; | |
256 | ||
257 | for (i = 0; i < 16 && aa[i] == bb[i]; i++); | |
258 | n = 8*i; | |
259 | if (i < 16) { | |
260 | m = aa[i]^bb[i]; | |
261 | if ((aa[i]&m) != 0 || (bb[i]&m) != m) return (-1); | |
262 | n += 8 - simple_mask_length(m); | |
263 | for (i++; i < 16; i++) | |
264 | if (aa[i] || bb[i] != 0xff) return (-1); | |
265 | } | |
266 | return (n); | |
267 | } break; | |
9314b85a MW |
268 | default: |
269 | abort(); | |
270 | } | |
271 | } | |
272 | ||
273 | /* Extract the port number (in host byte-order) from SA. */ | |
274 | static int port_from_sockaddr(const struct sockaddr *sa) | |
275 | { | |
276 | switch (sa->sa_family) { | |
277 | case AF_INET: return (ntohs(SIN(sa)->sin_port)); | |
2a06ea0b | 278 | case AF_INET6: return (ntohs(SIN6(sa)->sin6_port)); |
9314b85a MW |
279 | default: abort(); |
280 | } | |
281 | } | |
282 | ||
283 | /* Store the port number PORT (in host byte-order) in SA. */ | |
284 | static void port_to_sockaddr(struct sockaddr *sa, int port) | |
285 | { | |
286 | switch (sa->sa_family) { | |
287 | case AF_INET: SIN(sa)->sin_port = htons(port); break; | |
2a06ea0b | 288 | case AF_INET6: SIN6(sa)->sin6_port = htons(port); break; |
9314b85a MW |
289 | default: abort(); |
290 | } | |
291 | } | |
10cee633 | 292 | |
9314b85a MW |
293 | /* Extract the address part from SA and store it in A. */ |
294 | static void ipaddr_from_sockaddr(ipaddr *a, const struct sockaddr *sa) | |
295 | { | |
296 | switch (sa->sa_family) { | |
297 | case AF_INET: a->v4 = SIN(sa)->sin_addr; break; | |
2a06ea0b | 298 | case AF_INET6: a->v6 = SIN6(sa)->sin6_addr; break; |
9314b85a MW |
299 | default: abort(); |
300 | } | |
301 | } | |
302 | ||
303 | /* Copy a whole socket address about. */ | |
304 | static void copy_sockaddr(struct sockaddr *sa_dst, | |
305 | const struct sockaddr *sa_src) | |
306 | { memcpy(sa_dst, sa_src, family_socklen(sa_src->sa_family)); } | |
307 | ||
308 | /* Answer whether two addresses are equal. */ | |
309 | static int ipaddr_equal_p(int af, const ipaddr *a, const ipaddr *b) | |
310 | { | |
311 | switch (af) { | |
312 | case AF_INET: return (a->v4.s_addr == b->v4.s_addr); | |
2a06ea0b | 313 | case AF_INET6: return (memcmp(a->v6.s6_addr, b->v6.s6_addr, 16) == 0); |
9314b85a MW |
314 | default: abort(); |
315 | } | |
316 | } | |
317 | ||
318 | /* Answer whether the address part of SA is between A and B (inclusive). We | |
319 | * assume that SA has the correct address family. | |
320 | */ | |
321 | static int sockaddr_in_range_p(const struct sockaddr *sa, | |
322 | const ipaddr *a, const ipaddr *b) | |
323 | { | |
324 | switch (sa->sa_family) { | |
325 | case AF_INET: { | |
326 | unsigned long addr = ntohl(SIN(sa)->sin_addr.s_addr); | |
327 | return (ntohl(a->v4.s_addr) <= addr && | |
328 | addr <= ntohl(b->v4.s_addr)); | |
329 | } break; | |
2a06ea0b MW |
330 | case AF_INET6: { |
331 | const uint8_t *ss = SIN6(sa)->sin6_addr.s6_addr; | |
332 | const uint8_t *aa = a->v6.s6_addr, *bb = b->v6.s6_addr; | |
333 | int h = 1, l = 1; | |
334 | int i; | |
335 | ||
336 | for (i = 0; h && l && i < 16; i++, ss++, aa++, bb++) { | |
337 | if (*ss < *aa || *bb < *ss) return (0); | |
338 | if (*aa < *ss) l = 0; | |
339 | if (*ss < *bb) h = 0; | |
340 | } | |
341 | return (1); | |
342 | } break; | |
9314b85a MW |
343 | default: |
344 | abort(); | |
345 | } | |
346 | } | |
347 | ||
348 | /* Fill in SA with the appropriate wildcard address. */ | |
349 | static void wildcard_address(int af, struct sockaddr *sa) | |
350 | { | |
351 | switch (af) { | |
352 | case AF_INET: { | |
353 | struct sockaddr_in *sin = SIN(sa); | |
354 | memset(sin, 0, sizeof(*sin)); | |
355 | sin->sin_family = AF_INET; | |
356 | sin->sin_port = 0; | |
357 | sin->sin_addr.s_addr = INADDR_ANY; | |
358 | } break; | |
2a06ea0b MW |
359 | case AF_INET6: { |
360 | struct sockaddr_in6 *sin6 = SIN6(sa); | |
dc2b0a44 | 361 | memset(sin6, 0, sizeof(*sin6)); |
2a06ea0b MW |
362 | sin6->sin6_family = AF_INET6; |
363 | sin6->sin6_port = 0; | |
364 | sin6->sin6_addr = in6addr_any; | |
365 | sin6->sin6_scope_id = 0; | |
366 | sin6->sin6_flowinfo = 0; | |
367 | } break; | |
9314b85a MW |
368 | default: |
369 | abort(); | |
370 | } | |
371 | } | |
372 | ||
373 | /* Mask the address A, forcing all but the top PLEN bits to zero or one | |
374 | * according to HIGHP. | |
375 | */ | |
376 | static void mask_address(int af, ipaddr *a, int plen, int highp) | |
377 | { | |
378 | switch (af) { | |
379 | case AF_INET: { | |
380 | unsigned long addr = ntohl(a->v4.s_addr); | |
381 | unsigned long mask = plen ? ~0ul << (32 - plen) : 0; | |
382 | addr &= mask; | |
383 | if (highp) addr |= ~mask; | |
384 | a->v4.s_addr = htonl(addr & 0xffffffff); | |
385 | } break; | |
2a06ea0b MW |
386 | case AF_INET6: { |
387 | int i = plen/8; | |
388 | unsigned m = (0xff << (8 - plen%8)) & 0xff; | |
389 | unsigned s = highp ? 0xff : 0; | |
390 | if (m) { | |
391 | a->v6.s6_addr[i] = (a->v6.s6_addr[i] & m) | (s & ~m); | |
392 | i++; | |
393 | } | |
394 | for (; i < 16; i++) a->v6.s6_addr[i] = s; | |
395 | } break; | |
9314b85a MW |
396 | default: |
397 | abort(); | |
398 | } | |
399 | } | |
400 | ||
401 | /* Write a presentation form of SA to BUF, a buffer of length SZ. LEN is the | |
402 | * address length; if it's zero, look it up based on the address family. | |
403 | * Return a pointer to the string (which might, in an emergency, be a static | |
404 | * string rather than your buffer). | |
405 | */ | |
406 | static char *present_sockaddr(const struct sockaddr *sa, socklen_t len, | |
407 | char *buf, size_t sz) | |
408 | { | |
409 | #define WANT(n_) do { if (sz < (n_)) goto nospace; } while (0) | |
410 | #define PUTC(c_) do { *buf++ = (c_); sz--; } while (0) | |
411 | ||
412 | if (!sz) return "<no-space-in-buffer>"; | |
413 | if (!len) len = family_socklen(sa->sa_family); | |
414 | ||
415 | switch (sa->sa_family) { | |
416 | case AF_UNIX: { | |
417 | struct sockaddr_un *sun = SUN(sa); | |
418 | char *p = sun->sun_path; | |
419 | size_t n = len - offsetof(struct sockaddr_un, sun_path); | |
420 | ||
421 | assert(n); | |
422 | if (*p == 0) { | |
423 | WANT(1); PUTC('@'); | |
424 | p++; n--; | |
425 | while (n) { | |
426 | switch (*p) { | |
427 | case 0: WANT(2); PUTC('\\'); PUTC('0'); break; | |
428 | case '\a': WANT(2); PUTC('\\'); PUTC('a'); break; | |
429 | case '\n': WANT(2); PUTC('\\'); PUTC('n'); break; | |
430 | case '\r': WANT(2); PUTC('\\'); PUTC('r'); break; | |
431 | case '\t': WANT(2); PUTC('\\'); PUTC('t'); break; | |
432 | case '\v': WANT(2); PUTC('\\'); PUTC('v'); break; | |
433 | case '\\': WANT(2); PUTC('\\'); PUTC('\\'); break; | |
434 | default: | |
435 | if (*p > ' ' && *p <= '~') | |
436 | { WANT(1); PUTC(*p); } | |
437 | else { | |
438 | WANT(4); PUTC('\\'); PUTC('x'); | |
439 | PUTC((*p >> 4)&0xf); PUTC((*p >> 0)&0xf); | |
440 | } | |
441 | break; | |
442 | } | |
443 | p++; n--; | |
444 | } | |
445 | } else { | |
446 | if (*p != '/') { WANT(2); PUTC('.'); PUTC('/'); } | |
447 | while (n && *p) { WANT(1); PUTC(*p); p++; n--; } | |
448 | } | |
449 | WANT(1); PUTC(0); | |
450 | } break; | |
2a06ea0b | 451 | case AF_INET: case AF_INET6: { |
9314b85a MW |
452 | char addrbuf[NI_MAXHOST], portbuf[NI_MAXSERV]; |
453 | int err = getnameinfo(sa, len, | |
454 | addrbuf, sizeof(addrbuf), | |
455 | portbuf, sizeof(portbuf), | |
456 | NI_NUMERICHOST | NI_NUMERICSERV); | |
457 | assert(!err); | |
458 | snprintf(buf, sz, strchr(addrbuf, ':') ? "[%s]:%s" : "%s:%s", | |
459 | addrbuf, portbuf); | |
460 | } break; | |
461 | default: | |
462 | snprintf(buf, sz, "<unknown-address-family %d>", sa->sa_family); | |
463 | break; | |
464 | } | |
465 | return (buf); | |
466 | ||
467 | nospace: | |
468 | buf[sz - 1] = 0; | |
469 | return (buf); | |
470 | } | |
471 | ||
472 | /* Guess the family of a textual socket address. */ | |
473 | static int guess_address_family(const char *p) | |
2a06ea0b | 474 | { return (strchr(p, ':') ? AF_INET6 : AF_INET); } |
9314b85a MW |
475 | |
476 | /* Parse a socket address P and write the result to SA. */ | |
477 | static int parse_sockaddr(struct sockaddr *sa, const char *p) | |
478 | { | |
479 | char buf[ADDRBUFSZ]; | |
480 | char *q; | |
481 | struct addrinfo *ai, ai_hint = { 0 }; | |
482 | ||
483 | if (strlen(p) >= sizeof(buf) - 1) return (-1); | |
484 | strcpy(buf, p); p = buf; | |
485 | if (*p != '[') { | |
486 | if ((q = strchr(p, ':')) == 0) return (-1); | |
487 | *q++ = 0; | |
488 | } else { | |
489 | p++; | |
490 | if ((q = strchr(p, ']')) == 0) return (-1); | |
491 | *q++ = 0; | |
492 | if (*q != ':') return (-1); | |
493 | q++; | |
494 | } | |
495 | ||
496 | ai_hint.ai_family = AF_UNSPEC; | |
497 | ai_hint.ai_socktype = SOCK_DGRAM; | |
498 | ai_hint.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV; | |
499 | if (getaddrinfo(p, q, &ai_hint, &ai)) return (-1); | |
500 | memcpy(sa, ai->ai_addr, ai->ai_addrlen); | |
501 | freeaddrinfo(ai); | |
502 | return (0); | |
503 | } | |
504 | ||
1d1ccf4f | 505 | /*----- Access control lists ----------------------------------------------*/ |
e4976bb0 | 506 | |
507 | #ifdef DEBUG | |
508 | ||
1d1ccf4f | 509 | /* Write to standard error a description of the ACL node A. */ |
bb182ccf | 510 | static void dump_aclnode(const aclnode *a) |
e4976bb0 | 511 | { |
9314b85a MW |
512 | char buf[ADDRBUFSZ]; |
513 | const char *p; | |
514 | int plen; | |
e4976bb0 | 515 | |
e397f0bd | 516 | fprintf(stderr, "noip(%d): %c ", getpid(), a->act ? '+' : '-'); |
9314b85a MW |
517 | plen = common_prefix_length(a->af, &a->minaddr, &a->maxaddr); |
518 | p = inet_ntop(a->af, &a->minaddr, buf, sizeof(buf)); | |
519 | fprintf(stderr, strchr(p, ':') ? "[%s]" : "%s", p); | |
520 | if (plen < 0) { | |
521 | p = inet_ntop(a->af, &a->maxaddr, buf, sizeof(buf)); | |
522 | fprintf(stderr, strchr(p, ':') ? "-[%s]" : "-%s", p); | |
523 | } else if (plen < address_width(a->af)) | |
524 | fprintf(stderr, "/%d", plen); | |
e4976bb0 | 525 | if (a->minport != 0 || a->maxport != 0xffff) { |
526 | fprintf(stderr, ":%u", (unsigned)a->minport); | |
527 | if (a->minport != a->maxport) | |
528 | fprintf(stderr, "-%u", (unsigned)a->maxport); | |
529 | } | |
530 | fputc('\n', stderr); | |
531 | } | |
532 | ||
bb182ccf | 533 | static void dump_acl(const aclnode *a) |
1d1ccf4f MW |
534 | { |
535 | int act = ALLOW; | |
536 | ||
537 | for (; a; a = a->next) { | |
538 | dump_aclnode(a); | |
539 | act = a->act; | |
540 | } | |
e397f0bd | 541 | fprintf(stderr, "noip(%d): [default policy: %s]\n", getpid(), |
1d1ccf4f MW |
542 | act == ALLOW ? "DENY" : "ALLOW"); |
543 | } | |
544 | ||
e4976bb0 | 545 | #endif |
546 | ||
9314b85a | 547 | /* Returns nonzero if the ACL A allows the socket address SA. */ |
bb182ccf | 548 | static int acl_allows_p(const aclnode *a, const struct sockaddr *sa) |
e4976bb0 | 549 | { |
9314b85a | 550 | unsigned short port = port_from_sockaddr(sa); |
e4976bb0 | 551 | int act = ALLOW; |
e397f0bd | 552 | Dpid; |
e4976bb0 | 553 | |
9314b85a | 554 | D({ char buf[ADDRBUFSZ]; |
e397f0bd | 555 | fprintf(stderr, "noip(%d): check %s\n", pid, |
9314b85a | 556 | present_sockaddr(sa, 0, buf, sizeof(buf))); }) |
e4976bb0 | 557 | for (; a; a = a->next) { |
558 | D( dump_aclnode(a); ) | |
9314b85a | 559 | if (sockaddr_in_range_p(sa, &a->minaddr, &a->maxaddr) && |
e4976bb0 | 560 | a->minport <= port && port <= a->maxport) { |
e397f0bd MW |
561 | D( fprintf(stderr, "noip(%d): aha! %s\n", pid, |
562 | a->act ? "ALLOW" : "DENY"); ) | |
e4976bb0 | 563 | return (a->act); |
564 | } | |
565 | act = a->act; | |
566 | } | |
e397f0bd MW |
567 | D( fprintf(stderr, "noip(%d): nothing found: %s\n", pid, |
568 | act ? "DENY" : "ALLOW"); ) | |
e4976bb0 | 569 | return (!act); |
570 | } | |
571 | ||
1d1ccf4f | 572 | /*----- Socket address conversion -----------------------------------------*/ |
e4976bb0 | 573 | |
1d1ccf4f | 574 | /* Return a uniformly distributed integer between MIN and MAX inclusive. */ |
f6049fdd | 575 | static unsigned randrange(unsigned min, unsigned max) |
576 | { | |
577 | unsigned mask, i; | |
578 | ||
579 | /* It's so nice not to have to care about the quality of the generator | |
9314b85a MW |
580 | * much! |
581 | */ | |
f6049fdd | 582 | max -= min; |
583 | for (mask = 1; mask < max; mask = (mask << 1) | 1) | |
584 | ; | |
585 | do i = rand() & mask; while (i > max); | |
586 | return (i + min); | |
587 | } | |
588 | ||
1d1ccf4f MW |
589 | /* Return the status of Unix-domain socket address SUN. Returns: UNUSED if |
590 | * the socket doesn't exist; USED if the path refers to an active socket, or | |
591 | * isn't really a socket at all, or we can't tell without a careful search | |
592 | * and QUICKP is set; or STALE if the file refers to a socket which isn't | |
593 | * being used any more. | |
594 | */ | |
595 | static int unix_socket_status(struct sockaddr_un *sun, int quickp) | |
596 | { | |
597 | struct stat st; | |
598 | FILE *fp = 0; | |
599 | size_t len, n; | |
600 | int rc; | |
601 | char buf[256]; | |
602 | ||
603 | if (stat(sun->sun_path, &st)) | |
604 | return (errno == ENOENT ? UNUSED : USED); | |
605 | if (!S_ISSOCK(st.st_mode) || quickp) | |
606 | return (USED); | |
607 | rc = USED; | |
608 | if ((fp = fopen("/proc/net/unix", "r")) == 0) | |
609 | goto done; | |
72d85cdb | 610 | if (!fgets(buf, sizeof(buf), fp)) goto done; /* skip header */ |
1d1ccf4f MW |
611 | len = strlen(sun->sun_path); |
612 | while (fgets(buf, sizeof(buf), fp)) { | |
613 | n = strlen(buf); | |
614 | if (n >= len + 2 && buf[n - len - 2] == ' ' && buf[n - 1] == '\n' && | |
615 | memcmp(buf + n - len - 1, sun->sun_path, len) == 0) | |
616 | goto done; | |
617 | } | |
618 | if (ferror(fp)) | |
619 | goto done; | |
620 | rc = STALE; | |
621 | done: | |
622 | if (fp) fclose(fp); | |
623 | return (rc); | |
624 | } | |
625 | ||
9314b85a MW |
626 | /* Encode the Internet address SA as a Unix-domain address SUN. If WANT is |
627 | * WANT_FRESH, and SA's port number is zero, then we pick an arbitrary local | |
1d1ccf4f | 628 | * port. Otherwise we pick the port given. There's an unpleasant hack to |
9314b85a MW |
629 | * find servers bound to local wildcard addresses. Returns zero on success; |
630 | * -1 on failure. | |
1d1ccf4f | 631 | */ |
e4976bb0 | 632 | static int encode_inet_addr(struct sockaddr_un *sun, |
9314b85a | 633 | const struct sockaddr *sa, |
e4976bb0 | 634 | int want) |
635 | { | |
636 | int i; | |
3ef1fec9 | 637 | int desperatep = 0; |
9314b85a MW |
638 | address addr; |
639 | char buf[ADDRBUFSZ]; | |
e4976bb0 | 640 | int rc; |
641 | ||
e397f0bd | 642 | D( fprintf(stderr, "noip(%d): encode %s (%s)", getpid(), |
9314b85a | 643 | present_sockaddr(sa, 0, buf, sizeof(buf)), |
e4976bb0 | 644 | want == WANT_EXISTING ? "EXISTING" : "FRESH"); ) |
645 | sun->sun_family = AF_UNIX; | |
9314b85a MW |
646 | if (port_from_sockaddr(sa) || want == WANT_EXISTING) { |
647 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
648 | present_sockaddr(sa, 0, buf, sizeof(buf))); | |
e4976bb0 | 649 | rc = unix_socket_status(sun, 0); |
650 | if (rc == STALE) unlink(sun->sun_path); | |
651 | if (rc != USED && want == WANT_EXISTING) { | |
9314b85a MW |
652 | wildcard_address(sa->sa_family, &addr.sa); |
653 | port_to_sockaddr(&addr.sa, port_from_sockaddr(sa)); | |
654 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
655 | present_sockaddr(&addr.sa, 0, buf, sizeof(buf))); | |
e4976bb0 | 656 | if (unix_socket_status(sun, 0) == STALE) unlink(sun->sun_path); |
657 | } | |
658 | } else { | |
9314b85a | 659 | copy_sockaddr(&addr.sa, sa); |
f6049fdd | 660 | for (i = 0; i < 10; i++) { |
9314b85a MW |
661 | port_to_sockaddr(&addr.sa, randrange(minautoport, maxautoport)); |
662 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
663 | present_sockaddr(&addr.sa, 0, buf, sizeof(buf))); | |
f6049fdd | 664 | if (unix_socket_status(sun, 1) == UNUSED) goto found; |
665 | } | |
3ef1fec9 | 666 | for (desperatep = 0; desperatep < 2; desperatep++) { |
f6049fdd | 667 | for (i = minautoport; i <= maxautoport; i++) { |
9314b85a MW |
668 | port_to_sockaddr(&addr.sa, i); |
669 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
670 | present_sockaddr(&addr.sa, 0, buf, sizeof(buf))); | |
3ef1fec9 | 671 | rc = unix_socket_status(sun, !desperatep); |
e4976bb0 | 672 | switch (rc) { |
673 | case STALE: unlink(sun->sun_path); | |
674 | case UNUSED: goto found; | |
675 | } | |
676 | } | |
677 | } | |
678 | errno = EADDRINUSE; | |
679 | D( fprintf(stderr, " -- can't resolve\n"); ) | |
680 | return (-1); | |
681 | found:; | |
682 | } | |
683 | D( fprintf(stderr, " -> `%s'\n", sun->sun_path); ) | |
684 | return (0); | |
685 | } | |
686 | ||
9314b85a | 687 | /* Decode the Unix address SUN to an Internet address SIN. If AF_HINT is |
c0876c8c MW |
688 | * nonzero, an empty address (indicative of an unbound Unix-domain socket) is |
689 | * translated to a wildcard Internet address of the appropriate family. | |
690 | * Returns zero on success; -1 on failure (e.g., it wasn't one of our | |
691 | * addresses). | |
00a98a8a | 692 | */ |
9314b85a | 693 | static int decode_inet_addr(struct sockaddr *sa, int af_hint, |
e4976bb0 | 694 | const struct sockaddr_un *sun, |
9314b85a | 695 | socklen_t len) |
e4976bb0 | 696 | { |
9314b85a | 697 | char buf[ADDRBUFSZ]; |
a2114371 | 698 | size_t n = strlen(sockdir), nn; |
9314b85a | 699 | address addr; |
e4976bb0 | 700 | |
9314b85a MW |
701 | if (!sa) sa = &addr.sa; |
702 | if (sun->sun_family != AF_UNIX) return (-1); | |
703 | if (len > sizeof(*sun)) return (-1); | |
704 | ((char *)sun)[len] = 0; | |
a2114371 | 705 | nn = strlen(sun->sun_path); |
e397f0bd | 706 | D( fprintf(stderr, "noip(%d): decode `%s'", getpid(), sun->sun_path); ) |
9314b85a MW |
707 | if (af_hint && !sun->sun_path[0]) { |
708 | wildcard_address(af_hint, sa); | |
e4976bb0 | 709 | D( fprintf(stderr, " -- unbound socket\n"); ) |
710 | return (0); | |
711 | } | |
712 | if (nn < n + 1 || nn - n >= sizeof(buf) || sun->sun_path[n] != '/' || | |
713 | memcmp(sun->sun_path, sockdir, n) != 0) { | |
714 | D( fprintf(stderr, " -- not one of ours\n"); ) | |
715 | return (-1); | |
716 | } | |
9314b85a MW |
717 | if (parse_sockaddr(sa, sun->sun_path + n + 1)) return (-1); |
718 | D( fprintf(stderr, " -> %s\n", | |
719 | present_sockaddr(sa, 0, buf, sizeof(buf))); ) | |
e4976bb0 | 720 | return (0); |
721 | } | |
722 | ||
1d1ccf4f MW |
723 | /* SK is (or at least might be) a Unix-domain socket we created when an |
724 | * Internet socket was asked for. We've decided it should be an Internet | |
86134bfe MW |
725 | * socket after all, with family AF_HINT, so convert it. If TMP is not null, |
726 | * then don't replace the existing descriptor: store the new socket in *TMP | |
727 | * and return zero. | |
1d1ccf4f | 728 | */ |
86134bfe | 729 | static int fixup_real_ip_socket(int sk, int af_hint, int *tmp) |
e4976bb0 | 730 | { |
731 | int nsk; | |
732 | int type; | |
733 | int f, fd; | |
734 | struct sockaddr_un sun; | |
9314b85a | 735 | address addr; |
e4976bb0 | 736 | socklen_t len; |
737 | ||
738 | #define OPTS(_) \ | |
739 | _(DEBUG, int) \ | |
740 | _(REUSEADDR, int) \ | |
741 | _(DONTROUTE, int) \ | |
742 | _(BROADCAST, int) \ | |
743 | _(SNDBUF, int) \ | |
744 | _(RCVBUF, int) \ | |
745 | _(OOBINLINE, int) \ | |
746 | _(NO_CHECK, int) \ | |
747 | _(LINGER, struct linger) \ | |
748 | _(BSDCOMPAT, int) \ | |
749 | _(RCVLOWAT, int) \ | |
750 | _(RCVTIMEO, struct timeval) \ | |
751 | _(SNDTIMEO, struct timeval) | |
752 | ||
753 | len = sizeof(sun); | |
754 | if (real_getsockname(sk, SA(&sun), &len)) | |
755 | return (-1); | |
9314b85a | 756 | if (decode_inet_addr(&addr.sa, af_hint, &sun, len)) |
e4976bb0 | 757 | return (0); /* Not one of ours */ |
758 | len = sizeof(type); | |
759 | if (real_getsockopt(sk, SOL_SOCKET, SO_TYPE, &type, &len) < 0 || | |
9314b85a | 760 | (nsk = real_socket(addr.sa.sa_family, type, 0)) < 0) |
e4976bb0 | 761 | return (-1); |
762 | #define FIX(opt, ty) do { \ | |
763 | ty ov_; \ | |
764 | len = sizeof(ov_); \ | |
765 | if (real_getsockopt(sk, SOL_SOCKET, SO_##opt, &ov_, &len) < 0 || \ | |
766 | real_setsockopt(nsk, SOL_SOCKET, SO_##opt, &ov_, len)) { \ | |
9fb8e5c9 | 767 | close(nsk); \ |
e4976bb0 | 768 | return (-1); \ |
769 | } \ | |
770 | } while (0); | |
771 | OPTS(FIX) | |
772 | #undef FIX | |
86134bfe MW |
773 | if (tmp) |
774 | *tmp = nsk; | |
775 | else { | |
776 | if ((f = fcntl(sk, F_GETFL)) < 0 || | |
777 | (fd = fcntl(sk, F_GETFD)) < 0 || | |
778 | fcntl(nsk, F_SETFL, f) < 0 || | |
779 | dup2(nsk, sk) < 0) { | |
780 | close(nsk); | |
781 | return (-1); | |
782 | } | |
783 | unlink(sun.sun_path); | |
9fb8e5c9 | 784 | close(nsk); |
86134bfe MW |
785 | if (fcntl(sk, F_SETFD, fd) < 0) { |
786 | perror("noip: fixup_real_ip_socket F_SETFD"); | |
787 | abort(); | |
788 | } | |
e4976bb0 | 789 | } |
790 | return (0); | |
791 | } | |
792 | ||
1d1ccf4f | 793 | /* The socket SK is about to be used to communicate with the remote address |
9314b85a MW |
794 | * SA. Assign it a local address so that getpeername(2) does something |
795 | * useful. | |
1d1ccf4f | 796 | */ |
e4976bb0 | 797 | static int do_implicit_bind(int sk, const struct sockaddr **sa, |
798 | socklen_t *len, struct sockaddr_un *sun) | |
799 | { | |
9314b85a | 800 | address addr; |
e4976bb0 | 801 | socklen_t mylen = sizeof(*sun); |
802 | ||
9314b85a | 803 | if (acl_allows_p(connect_real, *sa)) { |
86134bfe | 804 | if (fixup_real_ip_socket(sk, (*sa)->sa_family, 0)) return (-1); |
e4976bb0 | 805 | } else { |
9314b85a | 806 | if (real_getsockname(sk, SA(sun), &mylen) < 0) return (-1); |
e4976bb0 | 807 | if (sun->sun_family == AF_UNIX) { |
808 | if (mylen < sizeof(*sun)) ((char *)sun)[mylen] = 0; | |
809 | if (!sun->sun_path[0]) { | |
9314b85a MW |
810 | wildcard_address((*sa)->sa_family, &addr.sa); |
811 | encode_inet_addr(sun, &addr.sa, WANT_FRESH); | |
812 | if (real_bind(sk, SA(sun), SUN_LEN(sun))) return (-1); | |
e4976bb0 | 813 | } |
9314b85a | 814 | encode_inet_addr(sun, *sa, WANT_EXISTING); |
e4976bb0 | 815 | *sa = SA(sun); |
816 | *len = SUN_LEN(sun); | |
817 | } | |
818 | } | |
819 | return (0); | |
820 | } | |
821 | ||
1d1ccf4f MW |
822 | /* We found the real address SA, with length LEN; if it's a Unix-domain |
823 | * address corresponding to a fake socket, convert it to cover up the | |
824 | * deception. Whatever happens, put the result at FAKE and store its length | |
825 | * at FAKELEN. | |
826 | */ | |
e4976bb0 | 827 | static void return_fake_name(struct sockaddr *sa, socklen_t len, |
828 | struct sockaddr *fake, socklen_t *fakelen) | |
829 | { | |
9314b85a | 830 | address addr; |
e4976bb0 | 831 | socklen_t alen; |
832 | ||
00a98a8a | 833 | if (sa->sa_family == AF_UNIX && |
9314b85a MW |
834 | !decode_inet_addr(&addr.sa, 0, SUN(sa), len)) { |
835 | sa = &addr.sa; | |
836 | len = family_socklen(addr.sa.sa_family); | |
e4976bb0 | 837 | } |
838 | alen = len; | |
9314b85a MW |
839 | if (len > *fakelen) len = *fakelen; |
840 | if (len > 0) memcpy(fake, sa, len); | |
e4976bb0 | 841 | *fakelen = alen; |
842 | } | |
843 | ||
1d1ccf4f | 844 | /*----- Configuration -----------------------------------------------------*/ |
e4976bb0 | 845 | |
1d1ccf4f | 846 | /* Return the process owner's home directory. */ |
e4976bb0 | 847 | static char *home(void) |
848 | { | |
849 | char *p; | |
850 | struct passwd *pw; | |
851 | ||
3ef1fec9 | 852 | if (getuid() == uid && |
853 | (p = getenv("HOME")) != 0) | |
854 | return (p); | |
855 | else if ((pw = getpwuid(uid)) != 0) | |
856 | return (pw->pw_dir); | |
857 | else | |
858 | return "/notexist"; | |
e4976bb0 | 859 | } |
860 | ||
1d1ccf4f | 861 | /* Return a good temporary directory to use. */ |
e4976bb0 | 862 | static char *tmpdir(void) |
863 | { | |
864 | char *p; | |
865 | ||
866 | if ((p = getenv("TMPDIR")) != 0) return (p); | |
867 | else if ((p = getenv("TMP")) != 0) return (p); | |
868 | else return ("/tmp"); | |
869 | } | |
870 | ||
1d1ccf4f | 871 | /* Return the user's name, or at least something distinctive. */ |
e4976bb0 | 872 | static char *user(void) |
873 | { | |
874 | static char buf[16]; | |
875 | char *p; | |
876 | struct passwd *pw; | |
877 | ||
878 | if ((p = getenv("USER")) != 0) return (p); | |
879 | else if ((p = getenv("LOGNAME")) != 0) return (p); | |
880 | else if ((pw = getpwuid(uid)) != 0) return (pw->pw_name); | |
881 | else { | |
882 | snprintf(buf, sizeof(buf), "uid-%lu", (unsigned long)uid); | |
883 | return (buf); | |
884 | } | |
885 | } | |
886 | ||
1d1ccf4f | 887 | /* Skip P over space characters. */ |
e4976bb0 | 888 | #define SKIPSPC do { while (*p && isspace(UC(*p))) p++; } while (0) |
1d1ccf4f MW |
889 | |
890 | /* Set Q to point to the next word following P, null-terminate it, and step P | |
891 | * past it. */ | |
e4976bb0 | 892 | #define NEXTWORD(q) do { \ |
893 | SKIPSPC; \ | |
894 | q = p; \ | |
895 | while (*p && !isspace(UC(*p))) p++; \ | |
896 | if (*p) *p++ = 0; \ | |
897 | } while (0) | |
1d1ccf4f MW |
898 | |
899 | /* Set Q to point to the next dotted-quad address, store the ending delimiter | |
900 | * in DEL, null-terminate it, and step P past it. */ | |
9314b85a MW |
901 | static void parse_nextaddr(char **pp, char **qq, int *del) |
902 | { | |
903 | char *p = *pp; | |
904 | ||
905 | SKIPSPC; | |
906 | if (*p == '[') { | |
907 | p++; SKIPSPC; | |
908 | *qq = p; | |
909 | p += strcspn(p, "]"); | |
910 | if (*p) *p++ = 0; | |
911 | *del = 0; | |
912 | } else { | |
913 | *qq = p; | |
914 | while (*p && (*p == '.' || isdigit(UC(*p)))) p++; | |
915 | *del = *p; | |
916 | if (*p) *p++ = 0; | |
917 | } | |
918 | *pp = p; | |
919 | } | |
1d1ccf4f MW |
920 | |
921 | /* Set Q to point to the next decimal number, store the ending delimiter in | |
922 | * DEL, null-terminate it, and step P past it. */ | |
e4976bb0 | 923 | #define NEXTNUMBER(q, del) do { \ |
924 | SKIPSPC; \ | |
925 | q = p; \ | |
926 | while (*p && isdigit(UC(*p))) p++; \ | |
927 | del = *p; \ | |
928 | if (*p) *p++ = 0; \ | |
929 | } while (0) | |
1d1ccf4f MW |
930 | |
931 | /* Push the character DEL back so we scan it again, unless it's zero | |
932 | * (end-of-file). */ | |
e4976bb0 | 933 | #define RESCAN(del) do { if (del) *--p = del; } while (0) |
1d1ccf4f MW |
934 | |
935 | /* Evaluate true if P is pointing to the word KW (and not some longer string | |
936 | * of which KW is a prefix). */ | |
937 | ||
e4976bb0 | 938 | #define KWMATCHP(kw) (strncmp(p, kw, sizeof(kw) - 1) == 0 && \ |
939 | !isalnum(UC(p[sizeof(kw) - 1])) && \ | |
940 | (p += sizeof(kw) - 1)) | |
9f82ba1f | 941 | |
1d1ccf4f MW |
942 | /* Parse a port list, starting at *PP. Port lists have the form |
943 | * [:LOW[-HIGH]]: if omitted, all ports are included; if HIGH is omitted, | |
944 | * it's as if HIGH = LOW. Store LOW in *MIN, HIGH in *MAX and set *PP to the | |
945 | * rest of the string. | |
946 | */ | |
e4976bb0 | 947 | static void parse_ports(char **pp, unsigned short *min, unsigned short *max) |
948 | { | |
949 | char *p = *pp, *q; | |
950 | int del; | |
951 | ||
952 | SKIPSPC; | |
f6049fdd | 953 | if (*p != ':') |
954 | { *min = 0; *max = 0xffff; } | |
955 | else { | |
e4976bb0 | 956 | p++; |
f6049fdd | 957 | NEXTNUMBER(q, del); *min = strtoul(q, 0, 0); RESCAN(del); |
e4976bb0 | 958 | SKIPSPC; |
f6049fdd | 959 | if (*p == '-') |
d83beb5c | 960 | { p++; NEXTNUMBER(q, del); *max = strtoul(q, 0, 0); RESCAN(del); } |
f6049fdd | 961 | else |
e4976bb0 | 962 | *max = *min; |
963 | } | |
964 | *pp = p; | |
965 | } | |
966 | ||
9314b85a MW |
967 | /* Make a new ACL node. ACT is the verdict; AF is the address family; |
968 | * MINADDR and MAXADDR are the ranges on IP addresses; MINPORT and MAXPORT | |
969 | * are the ranges on port numbers; TAIL is the list tail to attach the new | |
970 | * node to. | |
1d1ccf4f | 971 | */ |
e4976bb0 | 972 | #define ACLNODE(tail_, act_, \ |
9314b85a | 973 | af_, minaddr_, maxaddr_, minport_, maxport_) do { \ |
e4976bb0 | 974 | aclnode *a_; \ |
975 | NEW(a_); \ | |
9314b85a MW |
976 | a_->act = (act_); \ |
977 | a_->af = (af_); \ | |
978 | a_->minaddr = (minaddr_); a_->maxaddr = (maxaddr_); \ | |
979 | a_->minport = (minport_); a_->maxport = (maxport_); \ | |
e4976bb0 | 980 | *tail_ = a_; tail_ = &a_->next; \ |
981 | } while (0) | |
982 | ||
1d1ccf4f MW |
983 | /* Parse an ACL line. *PP points to the end of the line; *TAIL points to |
984 | * the list tail (i.e., the final link in the list). An ACL entry has the | |
985 | * form +|- [any | local | ADDR | ADDR - ADDR | ADDR/ADDR | ADDR/INT] PORTS | |
986 | * where PORTS is parsed by parse_ports above; an ACL line consists of a | |
987 | * comma-separated sequence of entries.. | |
988 | */ | |
e4976bb0 | 989 | static void parse_acl_line(char **pp, aclnode ***tail) |
990 | { | |
9314b85a | 991 | ipaddr minaddr, maxaddr; |
e4976bb0 | 992 | unsigned short minport, maxport; |
9314b85a | 993 | int i, af, n; |
e4976bb0 | 994 | int act; |
995 | int del; | |
996 | char *p = *pp; | |
997 | char *q; | |
998 | ||
a6d9626b | 999 | for (;;) { |
1000 | SKIPSPC; | |
1001 | if (*p == '+') act = ALLOW; | |
1002 | else if (*p == '-') act = DENY; | |
1003 | else goto bad; | |
e4976bb0 | 1004 | |
a6d9626b | 1005 | p++; |
1006 | SKIPSPC; | |
1007 | if (KWMATCHP("any")) { | |
9314b85a MW |
1008 | parse_ports(&p, &minport, &maxport); |
1009 | for (i = 0; address_families[i] >= 0; i++) { | |
1010 | af = address_families[i]; | |
1011 | memset(&minaddr, 0, sizeof(minaddr)); | |
1012 | maxaddr = minaddr; mask_address(af, &maxaddr, 0, 1); | |
1013 | ACLNODE(*tail, act, af, minaddr, maxaddr, minport, maxport); | |
1014 | } | |
a6d9626b | 1015 | } else if (KWMATCHP("local")) { |
1016 | parse_ports(&p, &minport, &maxport); | |
9314b85a MW |
1017 | for (i = 0; address_families[i] >= 0; i++) { |
1018 | af = address_families[i]; | |
1019 | memset(&minaddr, 0, sizeof(minaddr)); | |
1020 | maxaddr = minaddr; mask_address(af, &maxaddr, 0, 1); | |
1021 | ACLNODE(*tail, act, af, minaddr, minaddr, minport, maxport); | |
1022 | ACLNODE(*tail, act, af, maxaddr, maxaddr, minport, maxport); | |
1023 | } | |
a6d9626b | 1024 | for (i = 0; i < n_local_ipaddrs; i++) { |
9314b85a MW |
1025 | ACLNODE(*tail, act, local_ipaddrs[i].af, |
1026 | local_ipaddrs[i].addr, local_ipaddrs[i].addr, | |
1027 | minport, maxport); | |
a6d9626b | 1028 | } |
e4976bb0 | 1029 | } else { |
9314b85a MW |
1030 | parse_nextaddr(&p, &q, &del); |
1031 | af = guess_address_family(q); | |
1032 | if (inet_pton(af, q, &minaddr) <= 0) goto bad; | |
1033 | RESCAN(del); | |
1034 | SKIPSPC; | |
1035 | if (*p == '-') { | |
1036 | p++; | |
1037 | parse_nextaddr(&p, &q, &del); | |
1038 | if (inet_pton(af, q, &maxaddr) <= 0) goto bad; | |
e4976bb0 | 1039 | RESCAN(del); |
9314b85a MW |
1040 | } else if (*p == '/') { |
1041 | p++; | |
1042 | NEXTNUMBER(q, del); | |
1043 | n = strtoul(q, 0, 0); | |
1044 | maxaddr = minaddr; | |
1045 | mask_address(af, &minaddr, n, 0); | |
1046 | mask_address(af, &maxaddr, n, 1); | |
d5bf6247 | 1047 | RESCAN(del); |
9314b85a MW |
1048 | } else |
1049 | maxaddr = minaddr; | |
a6d9626b | 1050 | parse_ports(&p, &minport, &maxport); |
9314b85a | 1051 | ACLNODE(*tail, act, af, minaddr, maxaddr, minport, maxport); |
e4976bb0 | 1052 | } |
a6d9626b | 1053 | SKIPSPC; |
1054 | if (*p != ',') break; | |
1cce4a41 | 1055 | if (*p) p++; |
e4976bb0 | 1056 | } |
f797ea6d | 1057 | *pp = p; |
e4976bb0 | 1058 | return; |
1059 | ||
1060 | bad: | |
e397f0bd | 1061 | D( fprintf(stderr, "noip(%d): bad acl spec (ignored)\n", getpid()); ) |
e4976bb0 | 1062 | return; |
1063 | } | |
1064 | ||
1d1ccf4f | 1065 | /* Parse the autoports configuration directive. Syntax is MIN - MAX. */ |
f6049fdd | 1066 | static void parse_autoports(char **pp) |
1067 | { | |
1068 | char *p = *pp, *q; | |
1069 | unsigned x, y; | |
1070 | int del; | |
1071 | ||
1072 | SKIPSPC; | |
1073 | NEXTNUMBER(q, del); x = strtoul(q, 0, 0); RESCAN(del); | |
1074 | SKIPSPC; | |
1075 | if (*p != '-') goto bad; p++; | |
1076 | NEXTNUMBER(q, del); y = strtoul(q, 0, 0); RESCAN(del); | |
1077 | minautoport = x; maxautoport = y; | |
f797ea6d | 1078 | *pp = p; |
f6049fdd | 1079 | return; |
1080 | ||
1081 | bad: | |
e397f0bd | 1082 | D( fprintf(stderr, "noip(%d): bad port range (ignored)\n", getpid()); ) |
f6049fdd | 1083 | return; |
1084 | } | |
1085 | ||
1d1ccf4f MW |
1086 | /* Parse an ACL from an environment variable VAR, attaching it to the list |
1087 | * TAIL. */ | |
a6d9626b | 1088 | static void parse_acl_env(const char *var, aclnode ***tail) |
1089 | { | |
f6049fdd | 1090 | char *p, *q; |
a6d9626b | 1091 | |
1092 | if ((p = getenv(var)) != 0) { | |
f6049fdd | 1093 | p = q = xstrdup(p); |
1094 | parse_acl_line(&q, tail); | |
a6d9626b | 1095 | free(p); |
1096 | } | |
1097 | } | |
1098 | ||
1d1ccf4f | 1099 | /* Read the configuration from the config file and environment. */ |
e4976bb0 | 1100 | static void readconfig(void) |
1101 | { | |
1102 | FILE *fp; | |
1103 | char buf[1024]; | |
1104 | size_t n; | |
f6049fdd | 1105 | char *p, *q, *cmd; |
e397f0bd | 1106 | Dpid; |
e4976bb0 | 1107 | |
a6d9626b | 1108 | parse_acl_env("NOIP_REALBIND_BEFORE", &bind_tail); |
1109 | parse_acl_env("NOIP_REALCONNECT_BEFORE", &connect_tail); | |
f6049fdd | 1110 | if ((p = getenv("NOIP_AUTOPORTS")) != 0) { |
1111 | p = q = xstrdup(p); | |
1112 | parse_autoports(&q); | |
1113 | free(p); | |
1114 | } | |
4ab301de | 1115 | if ((p = getenv("NOIP_CONFIG")) == 0) |
1116 | snprintf(p = buf, sizeof(buf), "%s/.noip", home()); | |
e397f0bd | 1117 | D( fprintf(stderr, "noip(%d): config file: %s\n", pid, p); ) |
4ab301de | 1118 | |
1119 | if ((fp = fopen(p, "r")) == 0) { | |
e397f0bd MW |
1120 | D( fprintf(stderr, "noip(%d): couldn't read config: %s\n", |
1121 | pid, strerror(errno)); ) | |
f6049fdd | 1122 | goto done; |
4ab301de | 1123 | } |
e4976bb0 | 1124 | while (fgets(buf, sizeof(buf), fp)) { |
1125 | n = strlen(buf); | |
1126 | p = buf; | |
1127 | ||
1128 | SKIPSPC; | |
1129 | if (!*p || *p == '#') continue; | |
1130 | while (n && isspace(UC(buf[n - 1]))) n--; | |
1131 | buf[n] = 0; | |
1132 | NEXTWORD(cmd); | |
1133 | SKIPSPC; | |
1134 | ||
1135 | if (strcmp(cmd, "socketdir") == 0) | |
1136 | sockdir = xstrdup(p); | |
1137 | else if (strcmp(cmd, "realbind") == 0) | |
1138 | parse_acl_line(&p, &bind_tail); | |
1139 | else if (strcmp(cmd, "realconnect") == 0) | |
1140 | parse_acl_line(&p, &connect_tail); | |
f6049fdd | 1141 | else if (strcmp(cmd, "autoports") == 0) |
1142 | parse_autoports(&p); | |
e4976bb0 | 1143 | else if (strcmp(cmd, "debug") == 0) |
1144 | debug = *p ? atoi(p) : 1; | |
1145 | else | |
1146 | D( fprintf(stderr, "noip: bad config command %s\n", cmd); ) | |
1147 | } | |
1148 | fclose(fp); | |
1149 | ||
1150 | done: | |
a6d9626b | 1151 | parse_acl_env("NOIP_REALBIND", &bind_tail); |
1152 | parse_acl_env("NOIP_REALCONNECT", &connect_tail); | |
1153 | parse_acl_env("NOIP_REALBIND_AFTER", &bind_tail); | |
1154 | parse_acl_env("NOIP_REALCONNECT_AFTER", &connect_tail); | |
e4976bb0 | 1155 | *bind_tail = 0; |
1156 | *connect_tail = 0; | |
a6d9626b | 1157 | if (!sockdir) sockdir = getenv("NOIP_SOCKETDIR"); |
e4976bb0 | 1158 | if (!sockdir) { |
1159 | snprintf(buf, sizeof(buf), "%s/noip-%s", tmpdir(), user()); | |
1160 | sockdir = xstrdup(buf); | |
1161 | } | |
e397f0bd MW |
1162 | D( fprintf(stderr, "noip(%d): socketdir: %s\n", pid, sockdir); |
1163 | fprintf(stderr, "noip(%d): autoports: %u-%u\n", | |
1164 | pid, minautoport, maxautoport); | |
1165 | fprintf(stderr, "noip(%d): realbind acl:\n", pid); | |
e4976bb0 | 1166 | dump_acl(bind_real); |
e397f0bd | 1167 | fprintf(stderr, "noip(%d): realconnect acl:\n", pid); |
e4976bb0 | 1168 | dump_acl(connect_real); ) |
1169 | } | |
1170 | ||
1d1ccf4f | 1171 | /*----- Overridden system calls -------------------------------------------*/ |
e4976bb0 | 1172 | |
1173 | int socket(int pf, int ty, int proto) | |
1174 | { | |
8ce11853 | 1175 | switch (pf) { |
9314b85a MW |
1176 | default: |
1177 | if (!family_known_p(pf)) { | |
1178 | errno = EAFNOSUPPORT; | |
1179 | return (-1); | |
1180 | } | |
8ce11853 MW |
1181 | pf = PF_UNIX; |
1182 | proto = 0; | |
1183 | case PF_UNIX: | |
41c50995 MW |
1184 | #ifdef PF_NETLINK |
1185 | case PF_NETLINK: | |
1186 | #endif | |
9314b85a | 1187 | return (real_socket(pf, ty, proto)); |
e4976bb0 | 1188 | } |
e4976bb0 | 1189 | } |
1190 | ||
1191 | int socketpair(int pf, int ty, int proto, int *sk) | |
1192 | { | |
17085e3f | 1193 | if (family_known_p(pf)) { |
e4976bb0 | 1194 | pf = PF_UNIX; |
1195 | proto = 0; | |
1196 | } | |
1197 | return (real_socketpair(pf, ty, proto, sk)); | |
1198 | } | |
1199 | ||
1200 | int bind(int sk, const struct sockaddr *sa, socklen_t len) | |
1201 | { | |
1202 | struct sockaddr_un sun; | |
1203 | ||
9314b85a | 1204 | if (family_known_p(sa->sa_family)) { |
e4976bb0 | 1205 | PRESERVING_ERRNO({ |
9314b85a | 1206 | if (acl_allows_p(bind_real, sa)) { |
86134bfe | 1207 | if (fixup_real_ip_socket(sk, sa->sa_family, 0)) |
e4976bb0 | 1208 | return (-1); |
1209 | } else { | |
9314b85a | 1210 | encode_inet_addr(&sun, sa, WANT_FRESH); |
e4976bb0 | 1211 | sa = SA(&sun); |
1212 | len = SUN_LEN(&sun); | |
1213 | } | |
1214 | }); | |
1215 | } | |
9314b85a | 1216 | return (real_bind(sk, sa, len)); |
e4976bb0 | 1217 | } |
1218 | ||
1219 | int connect(int sk, const struct sockaddr *sa, socklen_t len) | |
1220 | { | |
1221 | struct sockaddr_un sun; | |
53390eff | 1222 | int rc; |
e4976bb0 | 1223 | |
9314b85a MW |
1224 | if (!family_known_p(sa->sa_family)) |
1225 | rc = real_connect(sk, sa, len); | |
1226 | else { | |
1227 | PRESERVING_ERRNO({ | |
1228 | do_implicit_bind(sk, &sa, &len, &sun); | |
1229 | }); | |
1230 | rc = real_connect(sk, sa, len); | |
1231 | if (rc < 0) { | |
1232 | switch (errno) { | |
1233 | case ENOENT: errno = ECONNREFUSED; break; | |
6df6f816 | 1234 | } |
9314b85a | 1235 | } |
53390eff | 1236 | } |
9314b85a | 1237 | return (rc); |
e4976bb0 | 1238 | } |
1239 | ||
1240 | ssize_t sendto(int sk, const void *buf, size_t len, int flags, | |
1241 | const struct sockaddr *to, socklen_t tolen) | |
1242 | { | |
1243 | struct sockaddr_un sun; | |
1244 | ||
17085e3f | 1245 | if (to && family_known_p(to->sa_family)) { |
e4976bb0 | 1246 | PRESERVING_ERRNO({ |
1247 | do_implicit_bind(sk, &to, &tolen, &sun); | |
1248 | }); | |
1249 | } | |
9314b85a | 1250 | return (real_sendto(sk, buf, len, flags, to, tolen)); |
e4976bb0 | 1251 | } |
1252 | ||
1253 | ssize_t recvfrom(int sk, void *buf, size_t len, int flags, | |
1254 | struct sockaddr *from, socklen_t *fromlen) | |
1255 | { | |
1256 | char sabuf[1024]; | |
1257 | socklen_t mylen = sizeof(sabuf); | |
1258 | ssize_t n; | |
1259 | ||
1260 | if (!from) | |
1261 | return real_recvfrom(sk, buf, len, flags, 0, 0); | |
1262 | PRESERVING_ERRNO({ | |
1263 | n = real_recvfrom(sk, buf, len, flags, SA(sabuf), &mylen); | |
1264 | if (n < 0) | |
1265 | return (-1); | |
1266 | return_fake_name(SA(sabuf), mylen, from, fromlen); | |
1267 | }); | |
1268 | return (n); | |
1269 | } | |
1270 | ||
1271 | ssize_t sendmsg(int sk, const struct msghdr *msg, int flags) | |
1272 | { | |
1273 | struct sockaddr_un sun; | |
1274 | const struct sockaddr *sa; | |
1275 | struct msghdr mymsg; | |
1276 | ||
17085e3f | 1277 | if (msg->msg_name && family_known_p(SA(msg->msg_name)->sa_family)) { |
e4976bb0 | 1278 | PRESERVING_ERRNO({ |
1279 | sa = SA(msg->msg_name); | |
1280 | mymsg = *msg; | |
1281 | do_implicit_bind(sk, &sa, &mymsg.msg_namelen, &sun); | |
1282 | mymsg.msg_name = SA(sa); | |
1283 | msg = &mymsg; | |
1284 | }); | |
1285 | } | |
9314b85a | 1286 | return (real_sendmsg(sk, msg, flags)); |
e4976bb0 | 1287 | } |
1288 | ||
1289 | ssize_t recvmsg(int sk, struct msghdr *msg, int flags) | |
1290 | { | |
1291 | char sabuf[1024]; | |
1292 | struct sockaddr *sa; | |
1293 | socklen_t len; | |
1294 | ssize_t n; | |
1295 | ||
1296 | if (!msg->msg_name) | |
9314b85a | 1297 | return (real_recvmsg(sk, msg, flags)); |
e4976bb0 | 1298 | PRESERVING_ERRNO({ |
1299 | sa = SA(msg->msg_name); | |
1300 | len = msg->msg_namelen; | |
1301 | msg->msg_name = sabuf; | |
1302 | msg->msg_namelen = sizeof(sabuf); | |
1303 | n = real_recvmsg(sk, msg, flags); | |
1304 | if (n < 0) | |
1305 | return (-1); | |
1306 | return_fake_name(SA(sabuf), msg->msg_namelen, sa, &len); | |
1307 | msg->msg_name = sa; | |
1308 | msg->msg_namelen = len; | |
1309 | }); | |
1310 | return (n); | |
1311 | } | |
1312 | ||
1313 | int accept(int sk, struct sockaddr *sa, socklen_t *len) | |
1314 | { | |
1315 | char sabuf[1024]; | |
1316 | socklen_t mylen = sizeof(sabuf); | |
1317 | int nsk = real_accept(sk, SA(sabuf), &mylen); | |
1318 | ||
1319 | if (nsk < 0) | |
1320 | return (-1); | |
1321 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1322 | return (nsk); | |
1323 | } | |
1324 | ||
1325 | int getsockname(int sk, struct sockaddr *sa, socklen_t *len) | |
1326 | { | |
1327 | PRESERVING_ERRNO({ | |
1328 | char sabuf[1024]; | |
1329 | socklen_t mylen = sizeof(sabuf); | |
1330 | if (real_getsockname(sk, SA(sabuf), &mylen)) | |
1331 | return (-1); | |
1332 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1333 | }); | |
1334 | return (0); | |
1335 | } | |
1336 | ||
1337 | int getpeername(int sk, struct sockaddr *sa, socklen_t *len) | |
1338 | { | |
1339 | PRESERVING_ERRNO({ | |
1340 | char sabuf[1024]; | |
1341 | socklen_t mylen = sizeof(sabuf); | |
1342 | if (real_getpeername(sk, SA(sabuf), &mylen)) | |
1343 | return (-1); | |
1344 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1345 | }); | |
1346 | return (0); | |
1347 | } | |
1348 | ||
1349 | int getsockopt(int sk, int lev, int opt, void *p, socklen_t *len) | |
1350 | { | |
1351 | switch (lev) { | |
1352 | case SOL_IP: | |
1353 | case SOL_TCP: | |
1354 | case SOL_UDP: | |
1355 | if (*len > 0) | |
1356 | memset(p, 0, *len); | |
1357 | return (0); | |
1358 | } | |
9314b85a | 1359 | return (real_getsockopt(sk, lev, opt, p, len)); |
e4976bb0 | 1360 | } |
1361 | ||
1362 | int setsockopt(int sk, int lev, int opt, const void *p, socklen_t len) | |
1363 | { | |
1364 | switch (lev) { | |
1365 | case SOL_IP: | |
1366 | case SOL_TCP: | |
1367 | case SOL_UDP: | |
1368 | return (0); | |
1369 | } | |
1370 | switch (opt) { | |
1371 | case SO_BINDTODEVICE: | |
1372 | case SO_ATTACH_FILTER: | |
1373 | case SO_DETACH_FILTER: | |
1374 | return (0); | |
1375 | } | |
9314b85a | 1376 | return (real_setsockopt(sk, lev, opt, p, len)); |
e4976bb0 | 1377 | } |
1378 | ||
658c1774 MW |
1379 | int ioctl(int fd, unsigned long op, ...) |
1380 | { | |
1381 | va_list ap; | |
1382 | void *arg; | |
1383 | int sk; | |
1384 | int rc; | |
1385 | ||
1386 | va_start(ap, op); | |
1387 | arg = va_arg(ap, void *); | |
1388 | ||
1389 | switch (op) { | |
1390 | case SIOCGIFADDR: | |
1391 | case SIOCGIFBRDADDR: | |
1392 | case SIOCGIFDSTADDR: | |
1393 | case SIOCGIFNETMASK: | |
1394 | PRESERVING_ERRNO({ | |
1395 | if (fixup_real_ip_socket(fd, AF_INET, &sk)) goto real; | |
1396 | }); | |
1397 | rc = real_ioctl(sk, op, arg); | |
1398 | PRESERVING_ERRNO({ close(sk); }); | |
1399 | break; | |
1400 | default: | |
1401 | real: | |
1402 | rc = real_ioctl(fd, op, arg); | |
1403 | break; | |
1404 | } | |
1405 | va_end(ap); | |
1406 | return (rc); | |
1407 | } | |
1408 | ||
1d1ccf4f | 1409 | /*----- Initialization ----------------------------------------------------*/ |
e4976bb0 | 1410 | |
1d1ccf4f | 1411 | /* Clean up the socket directory, deleting stale sockets. */ |
e4976bb0 | 1412 | static void cleanup_sockdir(void) |
1413 | { | |
1414 | DIR *dir; | |
1415 | struct dirent *d; | |
9314b85a | 1416 | address addr; |
e4976bb0 | 1417 | struct sockaddr_un sun; |
3ef1fec9 | 1418 | struct stat st; |
e397f0bd | 1419 | Dpid; |
e4976bb0 | 1420 | |
9314b85a | 1421 | if ((dir = opendir(sockdir)) == 0) return; |
4ab301de | 1422 | sun.sun_family = AF_UNIX; |
e4976bb0 | 1423 | while ((d = readdir(dir)) != 0) { |
1424 | if (d->d_name[0] == '.') continue; | |
1425 | snprintf(sun.sun_path, sizeof(sun.sun_path), | |
1426 | "%s/%s", sockdir, d->d_name); | |
9314b85a | 1427 | if (decode_inet_addr(&addr.sa, 0, &sun, SUN_LEN(&sun)) || |
3ef1fec9 | 1428 | stat(sun.sun_path, &st) || |
4ab301de | 1429 | !S_ISSOCK(st.st_mode)) { |
e397f0bd MW |
1430 | D( fprintf(stderr, "noip(%d): ignoring unknown socketdir entry `%s'\n", |
1431 | pid, sun.sun_path); ) | |
3ef1fec9 | 1432 | continue; |
4ab301de | 1433 | } |
e4976bb0 | 1434 | if (unix_socket_status(&sun, 0) == STALE) { |
e397f0bd MW |
1435 | D( fprintf(stderr, "noip(%d): clearing away stale socket %s\n", |
1436 | pid, d->d_name); ) | |
e4976bb0 | 1437 | unlink(sun.sun_path); |
1438 | } | |
1439 | } | |
1440 | closedir(dir); | |
1441 | } | |
1442 | ||
1d1ccf4f MW |
1443 | /* Find the addresses attached to local network interfaces, and remember them |
1444 | * in a table. | |
1445 | */ | |
e4976bb0 | 1446 | static void get_local_ipaddrs(void) |
1447 | { | |
9f1396d9 | 1448 | struct ifaddrs *ifa_head, *ifa; |
9314b85a | 1449 | ipaddr a; |
e4976bb0 | 1450 | int i; |
e397f0bd | 1451 | Dpid; |
e4976bb0 | 1452 | |
e397f0bd | 1453 | D( fprintf(stderr, "noip(%d): fetching local addresses...\n", pid); ) |
9f1396d9 MW |
1454 | if (getifaddrs(&ifa_head)) { perror("getifaddrs"); return; } |
1455 | for (n_local_ipaddrs = 0, ifa = ifa_head; | |
1456 | n_local_ipaddrs < MAX_LOCAL_IPADDRS && ifa; | |
1457 | ifa = ifa->ifa_next) { | |
9314b85a | 1458 | if (!ifa->ifa_addr || !family_known_p(ifa->ifa_addr->sa_family)) |
e4976bb0 | 1459 | continue; |
9314b85a MW |
1460 | ipaddr_from_sockaddr(&a, ifa->ifa_addr); |
1461 | D({ char buf[ADDRBUFSZ]; | |
e397f0bd MW |
1462 | fprintf(stderr, "noip(%d): local addr %s = %s", pid, |
1463 | ifa->ifa_name, | |
9314b85a MW |
1464 | inet_ntop(ifa->ifa_addr->sa_family, &a, |
1465 | buf, sizeof(buf))); }) | |
9f1396d9 | 1466 | for (i = 0; i < n_local_ipaddrs; i++) { |
9314b85a MW |
1467 | if (ifa->ifa_addr->sa_family == local_ipaddrs[i].af && |
1468 | ipaddr_equal_p(local_ipaddrs[i].af, &a, &local_ipaddrs[i].addr)) { | |
9f1396d9 MW |
1469 | D( fprintf(stderr, " (duplicate)\n"); ) |
1470 | goto skip; | |
1471 | } | |
1472 | } | |
1473 | D( fprintf(stderr, "\n"); ) | |
9314b85a MW |
1474 | local_ipaddrs[n_local_ipaddrs].af = ifa->ifa_addr->sa_family; |
1475 | local_ipaddrs[n_local_ipaddrs].addr = a; | |
9f1396d9 MW |
1476 | n_local_ipaddrs++; |
1477 | skip:; | |
e4976bb0 | 1478 | } |
9f1396d9 | 1479 | freeifaddrs(ifa_head); |
e4976bb0 | 1480 | } |
1481 | ||
1d1ccf4f | 1482 | /* Print the given message to standard error. Avoids stdio. */ |
72d85cdb | 1483 | static void printerr(const char *p) |
65f3786c | 1484 | { if (write(STDERR_FILENO, p, strlen(p))) ; } |
3ef1fec9 | 1485 | |
1d1ccf4f | 1486 | /* Create the socket directory, being careful about permissions. */ |
3ef1fec9 | 1487 | static void create_sockdir(void) |
1488 | { | |
1489 | struct stat st; | |
1490 | ||
b514afdd | 1491 | if (lstat(sockdir, &st)) { |
3ef1fec9 | 1492 | if (errno == ENOENT) { |
1493 | if (mkdir(sockdir, 0700)) { | |
1494 | perror("noip: creating socketdir"); | |
1495 | exit(127); | |
1496 | } | |
b514afdd | 1497 | if (!lstat(sockdir, &st)) |
3ef1fec9 | 1498 | goto check; |
1499 | } | |
1500 | perror("noip: checking socketdir"); | |
1501 | exit(127); | |
1502 | } | |
1503 | check: | |
1504 | if (!S_ISDIR(st.st_mode)) { | |
1505 | printerr("noip: bad socketdir: not a directory\n"); | |
1506 | exit(127); | |
1507 | } | |
1508 | if (st.st_uid != uid) { | |
1509 | printerr("noip: bad socketdir: not owner\n"); | |
1510 | exit(127); | |
1511 | } | |
1512 | if (st.st_mode & 077) { | |
1513 | printerr("noip: bad socketdir: not private\n"); | |
1514 | exit(127); | |
1515 | } | |
1516 | } | |
1517 | ||
1d1ccf4f MW |
1518 | /* Initialization function. */ |
1519 | static void setup(void) __attribute__((constructor)); | |
e4976bb0 | 1520 | static void setup(void) |
1521 | { | |
1522 | PRESERVING_ERRNO({ | |
1523 | char *p; | |
1524 | ||
1525 | import(); | |
3ef1fec9 | 1526 | uid = geteuid(); |
e4976bb0 | 1527 | if ((p = getenv("NOIP_DEBUG")) && atoi(p)) |
1528 | debug = 1; | |
1529 | get_local_ipaddrs(); | |
1530 | readconfig(); | |
3ef1fec9 | 1531 | create_sockdir(); |
e4976bb0 | 1532 | cleanup_sockdir(); |
1533 | }); | |
1534 | } | |
1d1ccf4f MW |
1535 | |
1536 | /*----- That's all, folks -------------------------------------------------*/ |