Commit | Line | Data |
---|---|---|
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 */ | |
1d1ccf4f MW |
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 | ||
7be80f86 MW |
91 | /* Implicit bind records */ |
92 | typedef struct impbind { | |
93 | struct impbind *next; | |
94 | int af, how; | |
95 | ipaddr minaddr, maxaddr, bindaddr; | |
96 | } impbind; | |
97 | enum { EXPLICIT, SAME }; | |
98 | ||
006dd63f MW |
99 | /* A type for an address range */ |
100 | typedef struct addrrange { | |
101 | int type; | |
102 | union { | |
103 | struct { int af; ipaddr min, max; } range; | |
104 | } u; | |
105 | } addrrange; | |
106 | enum { EMPTY, ANY, LOCAL, RANGE }; | |
107 | ||
1d1ccf4f | 108 | /* Local address records */ |
9314b85a MW |
109 | typedef struct full_ipaddr { |
110 | int af; | |
111 | ipaddr addr; | |
112 | } full_ipaddr; | |
2a06ea0b | 113 | #define MAX_LOCAL_IPADDRS 64 |
9314b85a | 114 | static full_ipaddr local_ipaddrs[MAX_LOCAL_IPADDRS]; |
e4976bb0 | 115 | static int n_local_ipaddrs; |
116 | ||
1d1ccf4f | 117 | /* General configuration */ |
e4976bb0 | 118 | static uid_t uid; |
119 | static char *sockdir = 0; | |
120 | static int debug = 0; | |
f6049fdd | 121 | static unsigned minautoport = 16384, maxautoport = 65536; |
e4976bb0 | 122 | |
1d1ccf4f | 123 | /* Access control lists */ |
e4976bb0 | 124 | static aclnode *bind_real, **bind_tail = &bind_real; |
125 | static aclnode *connect_real, **connect_tail = &connect_real; | |
7be80f86 | 126 | static impbind *impbinds, **impbind_tail = &impbinds; |
e4976bb0 | 127 | |
1d1ccf4f | 128 | /*----- Import the real versions of functions -----------------------------*/ |
e4976bb0 | 129 | |
1d1ccf4f | 130 | /* The list of functions to immport. */ |
e4976bb0 | 131 | #define IMPORTS(_) \ |
132 | _(socket, int, (int, int, int)) \ | |
133 | _(socketpair, int, (int, int, int, int *)) \ | |
134 | _(connect, int, (int, const struct sockaddr *, socklen_t)) \ | |
135 | _(bind, int, (int, const struct sockaddr *, socklen_t)) \ | |
136 | _(accept, int, (int, struct sockaddr *, socklen_t *)) \ | |
137 | _(getsockname, int, (int, struct sockaddr *, socklen_t *)) \ | |
138 | _(getpeername, int, (int, struct sockaddr *, socklen_t *)) \ | |
139 | _(getsockopt, int, (int, int, int, void *, socklen_t *)) \ | |
140 | _(setsockopt, int, (int, int, int, const void *, socklen_t)) \ | |
141 | _(sendto, ssize_t, (int, const void *buf, size_t, int, \ | |
142 | const struct sockaddr *to, socklen_t tolen)) \ | |
143 | _(recvfrom, ssize_t, (int, void *buf, size_t, int, \ | |
7d769c69 | 144 | struct sockaddr *from, socklen_t *fromlen)) \ |
e4976bb0 | 145 | _(sendmsg, ssize_t, (int, const struct msghdr *, int)) \ |
658c1774 MW |
146 | _(recvmsg, ssize_t, (int, struct msghdr *, int)) \ |
147 | _(ioctl, int, (int, unsigned long, ...)) | |
e4976bb0 | 148 | |
1d1ccf4f | 149 | /* Function pointers to set up. */ |
e4976bb0 | 150 | #define DECL(imp, ret, args) static ret (*real_##imp) args; |
151 | IMPORTS(DECL) | |
152 | #undef DECL | |
153 | ||
1d1ccf4f | 154 | /* Import the system calls. */ |
e4976bb0 | 155 | static void import(void) |
156 | { | |
157 | #define IMPORT(imp, ret, args) \ | |
158 | real_##imp = (ret (*)args)dlsym(RTLD_NEXT, #imp); | |
159 | IMPORTS(IMPORT) | |
160 | #undef IMPORT | |
161 | } | |
162 | ||
1d1ccf4f | 163 | /*----- Utilities ---------------------------------------------------------*/ |
e4976bb0 | 164 | |
1d1ccf4f | 165 | /* Socket address casts */ |
e4976bb0 | 166 | #define SA(sa) ((struct sockaddr *)(sa)) |
167 | #define SIN(sa) ((struct sockaddr_in *)(sa)) | |
2a06ea0b | 168 | #define SIN6(sa) ((struct sockaddr_in6 *)(sa)) |
e4976bb0 | 169 | #define SUN(sa) ((struct sockaddr_un *)(sa)) |
170 | ||
1d1ccf4f | 171 | /* Raw bytes */ |
e4976bb0 | 172 | #define UC(ch) ((unsigned char)(ch)) |
173 | ||
1d1ccf4f | 174 | /* Memory allocation */ |
e4976bb0 | 175 | #define NEW(x) ((x) = xmalloc(sizeof(*x))) |
176 | #define NEWV(x, n) ((x) = xmalloc(sizeof(*x) * (n))) | |
177 | ||
1d1ccf4f | 178 | /* Debugging */ |
e4976bb0 | 179 | #ifdef DEBUG |
180 | # define D(body) { if (debug) { body } } | |
e397f0bd | 181 | # define Dpid pid_t pid = debug ? getpid() : -1 |
e4976bb0 | 182 | #else |
183 | # define D(body) ; | |
e397f0bd | 184 | # define Dpid |
e4976bb0 | 185 | #endif |
186 | ||
1d1ccf4f | 187 | /* Preservation of error status */ |
e4976bb0 | 188 | #define PRESERVING_ERRNO(body) do { \ |
189 | int _err = errno; { body } errno = _err; \ | |
190 | } while (0) | |
191 | ||
1d1ccf4f | 192 | /* Allocate N bytes of memory; abort on failure. */ |
e4976bb0 | 193 | static void *xmalloc(size_t n) |
194 | { | |
195 | void *p; | |
196 | if (!n) return (0); | |
3ef1fec9 | 197 | if ((p = malloc(n)) == 0) { perror("malloc"); exit(127); } |
e4976bb0 | 198 | return (p); |
199 | } | |
200 | ||
1d1ccf4f | 201 | /* Allocate a copy of the null-terminated string P; abort on failure. */ |
e4976bb0 | 202 | static char *xstrdup(const char *p) |
203 | { | |
204 | size_t n = strlen(p) + 1; | |
205 | char *q = xmalloc(n); | |
206 | memcpy(q, p, n); | |
207 | return (q); | |
208 | } | |
9314b85a MW |
209 | |
210 | /*----- Address-type hacking ----------------------------------------------*/ | |
211 | ||
212 | /* If M is a simple mask, i.e., consists of a sequence of zero bits followed | |
213 | * by a sequence of one bits, then return the length of the latter sequence | |
214 | * (which may be zero); otherwise return -1. | |
215 | */ | |
216 | static int simple_mask_length(unsigned long m) | |
217 | { | |
218 | int n = 0; | |
219 | ||
220 | while (m & 1) { n++; m >>= 1; } | |
221 | return (m ? -1 : n); | |
222 | } | |
223 | ||
224 | /* Answer whether AF is an interesting address family. */ | |
225 | static int family_known_p(int af) | |
226 | { | |
227 | switch (af) { | |
228 | case AF_INET: | |
2a06ea0b | 229 | case AF_INET6: |
9314b85a MW |
230 | return (1); |
231 | default: | |
232 | return (0); | |
233 | } | |
234 | } | |
235 | ||
236 | /* Return the socket address length for address family AF. */ | |
237 | static socklen_t family_socklen(int af) | |
238 | { | |
239 | switch (af) { | |
240 | case AF_INET: return (sizeof(struct sockaddr_in)); | |
2a06ea0b | 241 | case AF_INET6: return (sizeof(struct sockaddr_in6)); |
9314b85a MW |
242 | default: abort(); |
243 | } | |
244 | } | |
245 | ||
246 | /* Return the width of addresses of kind AF. */ | |
247 | static int address_width(int af) | |
248 | { | |
249 | switch (af) { | |
250 | case AF_INET: return 32; | |
2a06ea0b | 251 | case AF_INET6: return 128; |
9314b85a MW |
252 | default: abort(); |
253 | } | |
254 | } | |
255 | ||
256 | /* If addresses A and B share a common prefix then return its length; | |
257 | * otherwise return -1. | |
258 | */ | |
259 | static int common_prefix_length(int af, const ipaddr *a, const ipaddr *b) | |
260 | { | |
261 | switch (af) { | |
262 | case AF_INET: { | |
263 | unsigned long aa = ntohl(a->v4.s_addr), bb = ntohl(b->v4.s_addr); | |
264 | unsigned long m = aa^bb; | |
265 | if ((aa&m) == 0 && (bb&m) == m) return (32 - simple_mask_length(m)); | |
266 | else return (-1); | |
267 | } break; | |
2a06ea0b MW |
268 | case AF_INET6: { |
269 | const uint8_t *aa = a->v6.s6_addr, *bb = b->v6.s6_addr; | |
270 | unsigned m; | |
271 | unsigned n; | |
272 | int i; | |
273 | ||
274 | for (i = 0; i < 16 && aa[i] == bb[i]; i++); | |
275 | n = 8*i; | |
276 | if (i < 16) { | |
277 | m = aa[i]^bb[i]; | |
278 | if ((aa[i]&m) != 0 || (bb[i]&m) != m) return (-1); | |
279 | n += 8 - simple_mask_length(m); | |
280 | for (i++; i < 16; i++) | |
281 | if (aa[i] || bb[i] != 0xff) return (-1); | |
282 | } | |
283 | return (n); | |
284 | } break; | |
9314b85a MW |
285 | default: |
286 | abort(); | |
287 | } | |
288 | } | |
289 | ||
290 | /* Extract the port number (in host byte-order) from SA. */ | |
291 | static int port_from_sockaddr(const struct sockaddr *sa) | |
292 | { | |
293 | switch (sa->sa_family) { | |
294 | case AF_INET: return (ntohs(SIN(sa)->sin_port)); | |
2a06ea0b | 295 | case AF_INET6: return (ntohs(SIN6(sa)->sin6_port)); |
9314b85a MW |
296 | default: abort(); |
297 | } | |
298 | } | |
299 | ||
300 | /* Store the port number PORT (in host byte-order) in SA. */ | |
301 | static void port_to_sockaddr(struct sockaddr *sa, int port) | |
302 | { | |
303 | switch (sa->sa_family) { | |
304 | case AF_INET: SIN(sa)->sin_port = htons(port); break; | |
2a06ea0b | 305 | case AF_INET6: SIN6(sa)->sin6_port = htons(port); break; |
9314b85a MW |
306 | default: abort(); |
307 | } | |
308 | } | |
10cee633 | 309 | |
9314b85a MW |
310 | /* Extract the address part from SA and store it in A. */ |
311 | static void ipaddr_from_sockaddr(ipaddr *a, const struct sockaddr *sa) | |
312 | { | |
313 | switch (sa->sa_family) { | |
314 | case AF_INET: a->v4 = SIN(sa)->sin_addr; break; | |
2a06ea0b | 315 | case AF_INET6: a->v6 = SIN6(sa)->sin6_addr; break; |
9314b85a MW |
316 | default: abort(); |
317 | } | |
318 | } | |
319 | ||
7be80f86 MW |
320 | /* Store the address A in SA. */ |
321 | static void ipaddr_to_sockaddr(struct sockaddr *sa, const ipaddr *a) | |
322 | { | |
323 | switch (sa->sa_family) { | |
324 | case AF_INET: | |
325 | SIN(sa)->sin_addr = a->v4; | |
326 | break; | |
327 | case AF_INET6: | |
328 | SIN6(sa)->sin6_addr = a->v6; | |
329 | SIN6(sa)->sin6_scope_id = 0; | |
330 | SIN6(sa)->sin6_flowinfo = 0; | |
331 | break; | |
332 | default: | |
333 | abort(); | |
334 | } | |
335 | } | |
336 | ||
9314b85a MW |
337 | /* Copy a whole socket address about. */ |
338 | static void copy_sockaddr(struct sockaddr *sa_dst, | |
339 | const struct sockaddr *sa_src) | |
340 | { memcpy(sa_dst, sa_src, family_socklen(sa_src->sa_family)); } | |
341 | ||
342 | /* Answer whether two addresses are equal. */ | |
343 | static int ipaddr_equal_p(int af, const ipaddr *a, const ipaddr *b) | |
344 | { | |
345 | switch (af) { | |
346 | case AF_INET: return (a->v4.s_addr == b->v4.s_addr); | |
2a06ea0b | 347 | case AF_INET6: return (memcmp(a->v6.s6_addr, b->v6.s6_addr, 16) == 0); |
9314b85a MW |
348 | default: abort(); |
349 | } | |
350 | } | |
351 | ||
352 | /* Answer whether the address part of SA is between A and B (inclusive). We | |
353 | * assume that SA has the correct address family. | |
354 | */ | |
355 | static int sockaddr_in_range_p(const struct sockaddr *sa, | |
356 | const ipaddr *a, const ipaddr *b) | |
357 | { | |
358 | switch (sa->sa_family) { | |
359 | case AF_INET: { | |
360 | unsigned long addr = ntohl(SIN(sa)->sin_addr.s_addr); | |
361 | return (ntohl(a->v4.s_addr) <= addr && | |
362 | addr <= ntohl(b->v4.s_addr)); | |
363 | } break; | |
2a06ea0b MW |
364 | case AF_INET6: { |
365 | const uint8_t *ss = SIN6(sa)->sin6_addr.s6_addr; | |
366 | const uint8_t *aa = a->v6.s6_addr, *bb = b->v6.s6_addr; | |
367 | int h = 1, l = 1; | |
368 | int i; | |
369 | ||
370 | for (i = 0; h && l && i < 16; i++, ss++, aa++, bb++) { | |
371 | if (*ss < *aa || *bb < *ss) return (0); | |
372 | if (*aa < *ss) l = 0; | |
373 | if (*ss < *bb) h = 0; | |
374 | } | |
375 | return (1); | |
376 | } break; | |
9314b85a MW |
377 | default: |
378 | abort(); | |
379 | } | |
380 | } | |
381 | ||
382 | /* Fill in SA with the appropriate wildcard address. */ | |
383 | static void wildcard_address(int af, struct sockaddr *sa) | |
384 | { | |
385 | switch (af) { | |
386 | case AF_INET: { | |
387 | struct sockaddr_in *sin = SIN(sa); | |
388 | memset(sin, 0, sizeof(*sin)); | |
389 | sin->sin_family = AF_INET; | |
390 | sin->sin_port = 0; | |
391 | sin->sin_addr.s_addr = INADDR_ANY; | |
392 | } break; | |
2a06ea0b MW |
393 | case AF_INET6: { |
394 | struct sockaddr_in6 *sin6 = SIN6(sa); | |
dc2b0a44 | 395 | memset(sin6, 0, sizeof(*sin6)); |
2a06ea0b MW |
396 | sin6->sin6_family = AF_INET6; |
397 | sin6->sin6_port = 0; | |
398 | sin6->sin6_addr = in6addr_any; | |
399 | sin6->sin6_scope_id = 0; | |
400 | sin6->sin6_flowinfo = 0; | |
401 | } break; | |
9314b85a MW |
402 | default: |
403 | abort(); | |
404 | } | |
405 | } | |
406 | ||
407 | /* Mask the address A, forcing all but the top PLEN bits to zero or one | |
408 | * according to HIGHP. | |
409 | */ | |
410 | static void mask_address(int af, ipaddr *a, int plen, int highp) | |
411 | { | |
412 | switch (af) { | |
413 | case AF_INET: { | |
414 | unsigned long addr = ntohl(a->v4.s_addr); | |
415 | unsigned long mask = plen ? ~0ul << (32 - plen) : 0; | |
416 | addr &= mask; | |
417 | if (highp) addr |= ~mask; | |
418 | a->v4.s_addr = htonl(addr & 0xffffffff); | |
419 | } break; | |
2a06ea0b MW |
420 | case AF_INET6: { |
421 | int i = plen/8; | |
422 | unsigned m = (0xff << (8 - plen%8)) & 0xff; | |
423 | unsigned s = highp ? 0xff : 0; | |
424 | if (m) { | |
425 | a->v6.s6_addr[i] = (a->v6.s6_addr[i] & m) | (s & ~m); | |
426 | i++; | |
427 | } | |
428 | for (; i < 16; i++) a->v6.s6_addr[i] = s; | |
429 | } break; | |
9314b85a MW |
430 | default: |
431 | abort(); | |
432 | } | |
433 | } | |
434 | ||
435 | /* Write a presentation form of SA to BUF, a buffer of length SZ. LEN is the | |
436 | * address length; if it's zero, look it up based on the address family. | |
437 | * Return a pointer to the string (which might, in an emergency, be a static | |
438 | * string rather than your buffer). | |
439 | */ | |
440 | static char *present_sockaddr(const struct sockaddr *sa, socklen_t len, | |
441 | char *buf, size_t sz) | |
442 | { | |
443 | #define WANT(n_) do { if (sz < (n_)) goto nospace; } while (0) | |
444 | #define PUTC(c_) do { *buf++ = (c_); sz--; } while (0) | |
445 | ||
ad0f7002 | 446 | if (!sa) return "<null-address>"; |
9314b85a MW |
447 | if (!sz) return "<no-space-in-buffer>"; |
448 | if (!len) len = family_socklen(sa->sa_family); | |
449 | ||
450 | switch (sa->sa_family) { | |
451 | case AF_UNIX: { | |
452 | struct sockaddr_un *sun = SUN(sa); | |
453 | char *p = sun->sun_path; | |
454 | size_t n = len - offsetof(struct sockaddr_un, sun_path); | |
455 | ||
456 | assert(n); | |
457 | if (*p == 0) { | |
458 | WANT(1); PUTC('@'); | |
459 | p++; n--; | |
460 | while (n) { | |
461 | switch (*p) { | |
462 | case 0: WANT(2); PUTC('\\'); PUTC('0'); break; | |
463 | case '\a': WANT(2); PUTC('\\'); PUTC('a'); break; | |
464 | case '\n': WANT(2); PUTC('\\'); PUTC('n'); break; | |
465 | case '\r': WANT(2); PUTC('\\'); PUTC('r'); break; | |
466 | case '\t': WANT(2); PUTC('\\'); PUTC('t'); break; | |
467 | case '\v': WANT(2); PUTC('\\'); PUTC('v'); break; | |
468 | case '\\': WANT(2); PUTC('\\'); PUTC('\\'); break; | |
469 | default: | |
470 | if (*p > ' ' && *p <= '~') | |
471 | { WANT(1); PUTC(*p); } | |
472 | else { | |
473 | WANT(4); PUTC('\\'); PUTC('x'); | |
474 | PUTC((*p >> 4)&0xf); PUTC((*p >> 0)&0xf); | |
475 | } | |
476 | break; | |
477 | } | |
478 | p++; n--; | |
479 | } | |
480 | } else { | |
481 | if (*p != '/') { WANT(2); PUTC('.'); PUTC('/'); } | |
482 | while (n && *p) { WANT(1); PUTC(*p); p++; n--; } | |
483 | } | |
484 | WANT(1); PUTC(0); | |
485 | } break; | |
2a06ea0b | 486 | case AF_INET: case AF_INET6: { |
9314b85a MW |
487 | char addrbuf[NI_MAXHOST], portbuf[NI_MAXSERV]; |
488 | int err = getnameinfo(sa, len, | |
489 | addrbuf, sizeof(addrbuf), | |
490 | portbuf, sizeof(portbuf), | |
491 | NI_NUMERICHOST | NI_NUMERICSERV); | |
492 | assert(!err); | |
493 | snprintf(buf, sz, strchr(addrbuf, ':') ? "[%s]:%s" : "%s:%s", | |
494 | addrbuf, portbuf); | |
495 | } break; | |
496 | default: | |
497 | snprintf(buf, sz, "<unknown-address-family %d>", sa->sa_family); | |
498 | break; | |
499 | } | |
500 | return (buf); | |
501 | ||
502 | nospace: | |
503 | buf[sz - 1] = 0; | |
504 | return (buf); | |
505 | } | |
506 | ||
507 | /* Guess the family of a textual socket address. */ | |
508 | static int guess_address_family(const char *p) | |
2a06ea0b | 509 | { return (strchr(p, ':') ? AF_INET6 : AF_INET); } |
9314b85a MW |
510 | |
511 | /* Parse a socket address P and write the result to SA. */ | |
512 | static int parse_sockaddr(struct sockaddr *sa, const char *p) | |
513 | { | |
514 | char buf[ADDRBUFSZ]; | |
515 | char *q; | |
516 | struct addrinfo *ai, ai_hint = { 0 }; | |
517 | ||
518 | if (strlen(p) >= sizeof(buf) - 1) return (-1); | |
519 | strcpy(buf, p); p = buf; | |
520 | if (*p != '[') { | |
521 | if ((q = strchr(p, ':')) == 0) return (-1); | |
522 | *q++ = 0; | |
523 | } else { | |
524 | p++; | |
525 | if ((q = strchr(p, ']')) == 0) return (-1); | |
526 | *q++ = 0; | |
527 | if (*q != ':') return (-1); | |
528 | q++; | |
529 | } | |
530 | ||
531 | ai_hint.ai_family = AF_UNSPEC; | |
532 | ai_hint.ai_socktype = SOCK_DGRAM; | |
533 | ai_hint.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV; | |
534 | if (getaddrinfo(p, q, &ai_hint, &ai)) return (-1); | |
535 | memcpy(sa, ai->ai_addr, ai->ai_addrlen); | |
536 | freeaddrinfo(ai); | |
537 | return (0); | |
538 | } | |
539 | ||
1d1ccf4f | 540 | /*----- Access control lists ----------------------------------------------*/ |
e4976bb0 | 541 | |
542 | #ifdef DEBUG | |
543 | ||
006dd63f | 544 | static void dump_addrrange(int af, const ipaddr *min, const ipaddr *max) |
e4976bb0 | 545 | { |
9314b85a MW |
546 | char buf[ADDRBUFSZ]; |
547 | const char *p; | |
548 | int plen; | |
e4976bb0 | 549 | |
006dd63f MW |
550 | plen = common_prefix_length(af, min, max); |
551 | p = inet_ntop(af, min, buf, sizeof(buf)); | |
9314b85a MW |
552 | fprintf(stderr, strchr(p, ':') ? "[%s]" : "%s", p); |
553 | if (plen < 0) { | |
006dd63f | 554 | p = inet_ntop(af, &max, buf, sizeof(buf)); |
9314b85a | 555 | fprintf(stderr, strchr(p, ':') ? "-[%s]" : "-%s", p); |
006dd63f | 556 | } else if (plen < address_width(af)) |
9314b85a | 557 | fprintf(stderr, "/%d", plen); |
006dd63f MW |
558 | } |
559 | ||
560 | /* Write to standard error a description of the ACL node A. */ | |
561 | static void dump_aclnode(const aclnode *a) | |
562 | { | |
563 | fprintf(stderr, "noip(%d): %c ", getpid(), a->act ? '+' : '-'); | |
564 | dump_addrrange(a->af, &a->minaddr, &a->maxaddr); | |
e4976bb0 | 565 | if (a->minport != 0 || a->maxport != 0xffff) { |
566 | fprintf(stderr, ":%u", (unsigned)a->minport); | |
567 | if (a->minport != a->maxport) | |
568 | fprintf(stderr, "-%u", (unsigned)a->maxport); | |
569 | } | |
570 | fputc('\n', stderr); | |
571 | } | |
572 | ||
bb182ccf | 573 | static void dump_acl(const aclnode *a) |
1d1ccf4f MW |
574 | { |
575 | int act = ALLOW; | |
576 | ||
577 | for (; a; a = a->next) { | |
578 | dump_aclnode(a); | |
579 | act = a->act; | |
580 | } | |
e397f0bd | 581 | fprintf(stderr, "noip(%d): [default policy: %s]\n", getpid(), |
1d1ccf4f MW |
582 | act == ALLOW ? "DENY" : "ALLOW"); |
583 | } | |
584 | ||
e4976bb0 | 585 | #endif |
586 | ||
9314b85a | 587 | /* Returns nonzero if the ACL A allows the socket address SA. */ |
bb182ccf | 588 | static int acl_allows_p(const aclnode *a, const struct sockaddr *sa) |
e4976bb0 | 589 | { |
9314b85a | 590 | unsigned short port = port_from_sockaddr(sa); |
e4976bb0 | 591 | int act = ALLOW; |
e397f0bd | 592 | Dpid; |
e4976bb0 | 593 | |
9314b85a | 594 | D({ char buf[ADDRBUFSZ]; |
e397f0bd | 595 | fprintf(stderr, "noip(%d): check %s\n", pid, |
9314b85a | 596 | present_sockaddr(sa, 0, buf, sizeof(buf))); }) |
e4976bb0 | 597 | for (; a; a = a->next) { |
598 | D( dump_aclnode(a); ) | |
deedf22d MW |
599 | if (a->af == sa->sa_family && |
600 | sockaddr_in_range_p(sa, &a->minaddr, &a->maxaddr) && | |
e4976bb0 | 601 | a->minport <= port && port <= a->maxport) { |
e397f0bd MW |
602 | D( fprintf(stderr, "noip(%d): aha! %s\n", pid, |
603 | a->act ? "ALLOW" : "DENY"); ) | |
e4976bb0 | 604 | return (a->act); |
605 | } | |
606 | act = a->act; | |
607 | } | |
e397f0bd MW |
608 | D( fprintf(stderr, "noip(%d): nothing found: %s\n", pid, |
609 | act ? "DENY" : "ALLOW"); ) | |
e4976bb0 | 610 | return (!act); |
611 | } | |
612 | ||
1d1ccf4f | 613 | /*----- Socket address conversion -----------------------------------------*/ |
e4976bb0 | 614 | |
1d1ccf4f | 615 | /* Return a uniformly distributed integer between MIN and MAX inclusive. */ |
f6049fdd | 616 | static unsigned randrange(unsigned min, unsigned max) |
617 | { | |
618 | unsigned mask, i; | |
619 | ||
620 | /* It's so nice not to have to care about the quality of the generator | |
9314b85a MW |
621 | * much! |
622 | */ | |
f6049fdd | 623 | max -= min; |
624 | for (mask = 1; mask < max; mask = (mask << 1) | 1) | |
625 | ; | |
626 | do i = rand() & mask; while (i > max); | |
627 | return (i + min); | |
628 | } | |
629 | ||
1d1ccf4f MW |
630 | /* Return the status of Unix-domain socket address SUN. Returns: UNUSED if |
631 | * the socket doesn't exist; USED if the path refers to an active socket, or | |
632 | * isn't really a socket at all, or we can't tell without a careful search | |
633 | * and QUICKP is set; or STALE if the file refers to a socket which isn't | |
634 | * being used any more. | |
635 | */ | |
636 | static int unix_socket_status(struct sockaddr_un *sun, int quickp) | |
637 | { | |
638 | struct stat st; | |
639 | FILE *fp = 0; | |
640 | size_t len, n; | |
641 | int rc; | |
642 | char buf[256]; | |
643 | ||
644 | if (stat(sun->sun_path, &st)) | |
645 | return (errno == ENOENT ? UNUSED : USED); | |
646 | if (!S_ISSOCK(st.st_mode) || quickp) | |
647 | return (USED); | |
648 | rc = USED; | |
649 | if ((fp = fopen("/proc/net/unix", "r")) == 0) | |
650 | goto done; | |
72d85cdb | 651 | if (!fgets(buf, sizeof(buf), fp)) goto done; /* skip header */ |
1d1ccf4f MW |
652 | len = strlen(sun->sun_path); |
653 | while (fgets(buf, sizeof(buf), fp)) { | |
654 | n = strlen(buf); | |
655 | if (n >= len + 2 && buf[n - len - 2] == ' ' && buf[n - 1] == '\n' && | |
656 | memcmp(buf + n - len - 1, sun->sun_path, len) == 0) | |
657 | goto done; | |
658 | } | |
659 | if (ferror(fp)) | |
660 | goto done; | |
661 | rc = STALE; | |
662 | done: | |
663 | if (fp) fclose(fp); | |
664 | return (rc); | |
665 | } | |
666 | ||
f6e0ea86 MW |
667 | /* Convert the IP address SA to a Unix-domain address SUN. Fail if the |
668 | * address seems already taken. If DESPARATEP then try cleaning up stale old | |
669 | * sockets. | |
670 | */ | |
671 | static int encode_unused_inet_addr(struct sockaddr *sa, | |
672 | struct sockaddr_un *sun, | |
673 | int desperatep) | |
674 | { | |
675 | address waddr; | |
676 | struct sockaddr_un wsun; | |
677 | int rc; | |
678 | char buf[ADDRBUFSZ]; | |
d0e289af | 679 | int port = port_from_sockaddr(sa); |
f6e0ea86 MW |
680 | |
681 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, | |
682 | present_sockaddr(sa, 0, buf, sizeof(buf))); | |
683 | if ((rc = unix_socket_status(sun, !desperatep)) == USED) return (-1); | |
684 | else if (rc == STALE) unlink(sun->sun_path); | |
685 | ||
686 | wildcard_address(sa->sa_family, &waddr.sa); | |
d0e289af | 687 | port_to_sockaddr(&waddr.sa, port); |
f6e0ea86 MW |
688 | snprintf(wsun.sun_path, sizeof(wsun.sun_path), "%s/%s", sockdir, |
689 | present_sockaddr(&waddr.sa, 0, buf, sizeof(buf))); | |
690 | if ((rc = unix_socket_status(&wsun, !desperatep)) == USED) return (-1); | |
691 | else if (rc == STALE) unlink(wsun.sun_path); | |
692 | ||
693 | return (0); | |
694 | } | |
695 | ||
4b9d1fad MW |
696 | /* Encode the Internet address SA as a Unix-domain address SUN. If the flag |
697 | * `ENCF_FRESH' is set, and SA's port number is zero, then we pick an | |
698 | * arbitrary local port. Otherwise we pick the port given. There's an | |
699 | * unpleasant hack to find servers bound to local wildcard addresses. | |
700 | * Returns zero on success; -1 on failure. | |
1d1ccf4f | 701 | */ |
4b9d1fad | 702 | #define ENCF_FRESH 1u |
e4976bb0 | 703 | static int encode_inet_addr(struct sockaddr_un *sun, |
9314b85a | 704 | const struct sockaddr *sa, |
4b9d1fad | 705 | unsigned f) |
e4976bb0 | 706 | { |
707 | int i; | |
3ef1fec9 | 708 | int desperatep = 0; |
9314b85a | 709 | address addr; |
d0e289af | 710 | int port = port_from_sockaddr(sa); |
9314b85a | 711 | char buf[ADDRBUFSZ]; |
e4976bb0 | 712 | int rc; |
713 | ||
e397f0bd | 714 | D( fprintf(stderr, "noip(%d): encode %s (%s)", getpid(), |
9314b85a | 715 | present_sockaddr(sa, 0, buf, sizeof(buf)), |
4b9d1fad | 716 | (f&ENCF_FRESH) ? "FRESH" : "EXISTING"); ) |
e4976bb0 | 717 | sun->sun_family = AF_UNIX; |
4b9d1fad | 718 | if (port || !(f&ENCF_FRESH)) { |
9314b85a MW |
719 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, |
720 | present_sockaddr(sa, 0, buf, sizeof(buf))); | |
e4976bb0 | 721 | rc = unix_socket_status(sun, 0); |
722 | if (rc == STALE) unlink(sun->sun_path); | |
4b9d1fad | 723 | if (rc != USED && !(f&ENCF_FRESH)) { |
9314b85a | 724 | wildcard_address(sa->sa_family, &addr.sa); |
d0e289af | 725 | port_to_sockaddr(&addr.sa, port); |
9314b85a MW |
726 | snprintf(sun->sun_path, sizeof(sun->sun_path), "%s/%s", sockdir, |
727 | present_sockaddr(&addr.sa, 0, buf, sizeof(buf))); | |
e4976bb0 | 728 | if (unix_socket_status(sun, 0) == STALE) unlink(sun->sun_path); |
729 | } | |
730 | } else { | |
9314b85a | 731 | copy_sockaddr(&addr.sa, sa); |
f6049fdd | 732 | for (i = 0; i < 10; i++) { |
9314b85a | 733 | port_to_sockaddr(&addr.sa, randrange(minautoport, maxautoport)); |
f6e0ea86 | 734 | if (!encode_unused_inet_addr(&addr.sa, sun, 0)) goto found; |
f6049fdd | 735 | } |
3ef1fec9 | 736 | for (desperatep = 0; desperatep < 2; desperatep++) { |
f6049fdd | 737 | for (i = minautoport; i <= maxautoport; i++) { |
9314b85a | 738 | port_to_sockaddr(&addr.sa, i); |
f6e0ea86 | 739 | if (!encode_unused_inet_addr(&addr.sa, sun, 0)) goto found; |
e4976bb0 | 740 | } |
741 | } | |
742 | errno = EADDRINUSE; | |
743 | D( fprintf(stderr, " -- can't resolve\n"); ) | |
744 | return (-1); | |
745 | found:; | |
746 | } | |
747 | D( fprintf(stderr, " -> `%s'\n", sun->sun_path); ) | |
748 | return (0); | |
749 | } | |
750 | ||
9314b85a | 751 | /* Decode the Unix address SUN to an Internet address SIN. If AF_HINT is |
c0876c8c MW |
752 | * nonzero, an empty address (indicative of an unbound Unix-domain socket) is |
753 | * translated to a wildcard Internet address of the appropriate family. | |
754 | * Returns zero on success; -1 on failure (e.g., it wasn't one of our | |
755 | * addresses). | |
00a98a8a | 756 | */ |
9314b85a | 757 | static int decode_inet_addr(struct sockaddr *sa, int af_hint, |
e4976bb0 | 758 | const struct sockaddr_un *sun, |
9314b85a | 759 | socklen_t len) |
e4976bb0 | 760 | { |
9314b85a | 761 | char buf[ADDRBUFSZ]; |
a2114371 | 762 | size_t n = strlen(sockdir), nn; |
9314b85a | 763 | address addr; |
e4976bb0 | 764 | |
9314b85a MW |
765 | if (!sa) sa = &addr.sa; |
766 | if (sun->sun_family != AF_UNIX) return (-1); | |
767 | if (len > sizeof(*sun)) return (-1); | |
768 | ((char *)sun)[len] = 0; | |
a2114371 | 769 | nn = strlen(sun->sun_path); |
e397f0bd | 770 | D( fprintf(stderr, "noip(%d): decode `%s'", getpid(), sun->sun_path); ) |
9314b85a MW |
771 | if (af_hint && !sun->sun_path[0]) { |
772 | wildcard_address(af_hint, sa); | |
e4976bb0 | 773 | D( fprintf(stderr, " -- unbound socket\n"); ) |
774 | return (0); | |
775 | } | |
776 | if (nn < n + 1 || nn - n >= sizeof(buf) || sun->sun_path[n] != '/' || | |
777 | memcmp(sun->sun_path, sockdir, n) != 0) { | |
778 | D( fprintf(stderr, " -- not one of ours\n"); ) | |
779 | return (-1); | |
780 | } | |
9314b85a MW |
781 | if (parse_sockaddr(sa, sun->sun_path + n + 1)) return (-1); |
782 | D( fprintf(stderr, " -> %s\n", | |
783 | present_sockaddr(sa, 0, buf, sizeof(buf))); ) | |
e4976bb0 | 784 | return (0); |
785 | } | |
786 | ||
1d1ccf4f MW |
787 | /* SK is (or at least might be) a Unix-domain socket we created when an |
788 | * Internet socket was asked for. We've decided it should be an Internet | |
86134bfe MW |
789 | * socket after all, with family AF_HINT, so convert it. If TMP is not null, |
790 | * then don't replace the existing descriptor: store the new socket in *TMP | |
791 | * and return zero. | |
1d1ccf4f | 792 | */ |
86134bfe | 793 | static int fixup_real_ip_socket(int sk, int af_hint, int *tmp) |
e4976bb0 | 794 | { |
795 | int nsk; | |
796 | int type; | |
797 | int f, fd; | |
798 | struct sockaddr_un sun; | |
9314b85a | 799 | address addr; |
e4976bb0 | 800 | socklen_t len; |
801 | ||
802 | #define OPTS(_) \ | |
803 | _(DEBUG, int) \ | |
804 | _(REUSEADDR, int) \ | |
805 | _(DONTROUTE, int) \ | |
806 | _(BROADCAST, int) \ | |
807 | _(SNDBUF, int) \ | |
808 | _(RCVBUF, int) \ | |
809 | _(OOBINLINE, int) \ | |
810 | _(NO_CHECK, int) \ | |
811 | _(LINGER, struct linger) \ | |
812 | _(BSDCOMPAT, int) \ | |
813 | _(RCVLOWAT, int) \ | |
814 | _(RCVTIMEO, struct timeval) \ | |
815 | _(SNDTIMEO, struct timeval) | |
816 | ||
817 | len = sizeof(sun); | |
818 | if (real_getsockname(sk, SA(&sun), &len)) | |
819 | return (-1); | |
9314b85a | 820 | if (decode_inet_addr(&addr.sa, af_hint, &sun, len)) |
e4976bb0 | 821 | return (0); /* Not one of ours */ |
822 | len = sizeof(type); | |
823 | if (real_getsockopt(sk, SOL_SOCKET, SO_TYPE, &type, &len) < 0 || | |
9314b85a | 824 | (nsk = real_socket(addr.sa.sa_family, type, 0)) < 0) |
e4976bb0 | 825 | return (-1); |
826 | #define FIX(opt, ty) do { \ | |
827 | ty ov_; \ | |
828 | len = sizeof(ov_); \ | |
829 | if (real_getsockopt(sk, SOL_SOCKET, SO_##opt, &ov_, &len) < 0 || \ | |
830 | real_setsockopt(nsk, SOL_SOCKET, SO_##opt, &ov_, len)) { \ | |
9fb8e5c9 | 831 | close(nsk); \ |
e4976bb0 | 832 | return (-1); \ |
833 | } \ | |
834 | } while (0); | |
835 | OPTS(FIX) | |
836 | #undef FIX | |
86134bfe MW |
837 | if (tmp) |
838 | *tmp = nsk; | |
839 | else { | |
840 | if ((f = fcntl(sk, F_GETFL)) < 0 || | |
841 | (fd = fcntl(sk, F_GETFD)) < 0 || | |
842 | fcntl(nsk, F_SETFL, f) < 0 || | |
843 | dup2(nsk, sk) < 0) { | |
844 | close(nsk); | |
845 | return (-1); | |
846 | } | |
847 | unlink(sun.sun_path); | |
9fb8e5c9 | 848 | close(nsk); |
86134bfe MW |
849 | if (fcntl(sk, F_SETFD, fd) < 0) { |
850 | perror("noip: fixup_real_ip_socket F_SETFD"); | |
851 | abort(); | |
852 | } | |
e4976bb0 | 853 | } |
854 | return (0); | |
855 | } | |
856 | ||
7be80f86 MW |
857 | /* We found the real address SA, with length LEN; if it's a Unix-domain |
858 | * address corresponding to a fake socket, convert it to cover up the | |
859 | * deception. Whatever happens, put the result at FAKE and store its length | |
860 | * at FAKELEN. | |
861 | */ | |
862 | static void return_fake_name(struct sockaddr *sa, socklen_t len, | |
863 | struct sockaddr *fake, socklen_t *fakelen) | |
864 | { | |
865 | address addr; | |
866 | socklen_t alen; | |
867 | ||
868 | if (sa->sa_family == AF_UNIX && | |
869 | !decode_inet_addr(&addr.sa, 0, SUN(sa), len)) { | |
870 | sa = &addr.sa; | |
871 | len = family_socklen(addr.sa.sa_family); | |
872 | } | |
873 | alen = len; | |
874 | if (len > *fakelen) len = *fakelen; | |
875 | if (len > 0) memcpy(fake, sa, len); | |
876 | *fakelen = alen; | |
877 | } | |
878 | ||
879 | /*----- Implicit binding --------------------------------------------------*/ | |
880 | ||
881 | #ifdef DEBUG | |
882 | ||
883 | static void dump_impbind(const impbind *i) | |
884 | { | |
885 | char buf[ADDRBUFSZ]; | |
886 | ||
887 | fprintf(stderr, "noip(%d): ", getpid()); | |
888 | dump_addrrange(i->af, &i->minaddr, &i->maxaddr); | |
889 | switch (i->how) { | |
890 | case SAME: fprintf(stderr, " <self>"); break; | |
891 | case EXPLICIT: | |
892 | fprintf(stderr, " %s", inet_ntop(i->af, &i->bindaddr, | |
893 | buf, sizeof(buf))); | |
894 | break; | |
895 | default: abort(); | |
896 | } | |
897 | fputc('\n', stderr); | |
898 | } | |
899 | ||
900 | static void dump_impbind_list(void) | |
901 | { | |
902 | const impbind *i; | |
903 | ||
904 | for (i = impbinds; i; i = i->next) dump_impbind(i); | |
905 | } | |
906 | ||
907 | #endif | |
908 | ||
1d1ccf4f | 909 | /* The socket SK is about to be used to communicate with the remote address |
9314b85a MW |
910 | * SA. Assign it a local address so that getpeername(2) does something |
911 | * useful. | |
1d1ccf4f | 912 | */ |
e4976bb0 | 913 | static int do_implicit_bind(int sk, const struct sockaddr **sa, |
914 | socklen_t *len, struct sockaddr_un *sun) | |
915 | { | |
9314b85a | 916 | address addr; |
e4976bb0 | 917 | socklen_t mylen = sizeof(*sun); |
7be80f86 MW |
918 | const impbind *i; |
919 | Dpid; | |
e4976bb0 | 920 | |
9314b85a | 921 | if (acl_allows_p(connect_real, *sa)) { |
86134bfe | 922 | if (fixup_real_ip_socket(sk, (*sa)->sa_family, 0)) return (-1); |
e4976bb0 | 923 | } else { |
9314b85a | 924 | if (real_getsockname(sk, SA(sun), &mylen) < 0) return (-1); |
e4976bb0 | 925 | if (sun->sun_family == AF_UNIX) { |
926 | if (mylen < sizeof(*sun)) ((char *)sun)[mylen] = 0; | |
927 | if (!sun->sun_path[0]) { | |
7be80f86 MW |
928 | D( fprintf(stderr, "noip(%d): checking impbind list...\n", pid); ) |
929 | for (i = impbinds; i; i = i->next) { | |
930 | D( dump_impbind(i); ) | |
931 | if ((*sa)->sa_family == i->af && | |
932 | sockaddr_in_range_p(*sa, &i->minaddr, &i->maxaddr)) { | |
933 | D( fprintf(stderr, "noip(%d): match!\n", pid); ) | |
934 | addr.sa.sa_family = (*sa)->sa_family; | |
935 | ipaddr_to_sockaddr(&addr.sa, &i->bindaddr); | |
936 | goto found; | |
937 | } | |
938 | } | |
939 | D( fprintf(stderr, "noip(%d): no match; using wildcard\n", pid); ) | |
9314b85a | 940 | wildcard_address((*sa)->sa_family, &addr.sa); |
7be80f86 | 941 | found: |
4b9d1fad | 942 | encode_inet_addr(sun, &addr.sa, ENCF_FRESH); |
9314b85a | 943 | if (real_bind(sk, SA(sun), SUN_LEN(sun))) return (-1); |
e4976bb0 | 944 | } |
4b9d1fad | 945 | encode_inet_addr(sun, *sa, 0); |
e4976bb0 | 946 | *sa = SA(sun); |
947 | *len = SUN_LEN(sun); | |
948 | } | |
949 | } | |
950 | return (0); | |
951 | } | |
952 | ||
1d1ccf4f | 953 | /*----- Configuration -----------------------------------------------------*/ |
e4976bb0 | 954 | |
1d1ccf4f | 955 | /* Return the process owner's home directory. */ |
e4976bb0 | 956 | static char *home(void) |
957 | { | |
958 | char *p; | |
959 | struct passwd *pw; | |
960 | ||
3ef1fec9 | 961 | if (getuid() == uid && |
962 | (p = getenv("HOME")) != 0) | |
963 | return (p); | |
964 | else if ((pw = getpwuid(uid)) != 0) | |
965 | return (pw->pw_dir); | |
966 | else | |
967 | return "/notexist"; | |
e4976bb0 | 968 | } |
969 | ||
1d1ccf4f | 970 | /* Return a good temporary directory to use. */ |
e4976bb0 | 971 | static char *tmpdir(void) |
972 | { | |
973 | char *p; | |
974 | ||
975 | if ((p = getenv("TMPDIR")) != 0) return (p); | |
976 | else if ((p = getenv("TMP")) != 0) return (p); | |
977 | else return ("/tmp"); | |
978 | } | |
979 | ||
1d1ccf4f | 980 | /* Return the user's name, or at least something distinctive. */ |
e4976bb0 | 981 | static char *user(void) |
982 | { | |
983 | static char buf[16]; | |
984 | char *p; | |
985 | struct passwd *pw; | |
986 | ||
987 | if ((p = getenv("USER")) != 0) return (p); | |
988 | else if ((p = getenv("LOGNAME")) != 0) return (p); | |
989 | else if ((pw = getpwuid(uid)) != 0) return (pw->pw_name); | |
990 | else { | |
991 | snprintf(buf, sizeof(buf), "uid-%lu", (unsigned long)uid); | |
992 | return (buf); | |
993 | } | |
994 | } | |
995 | ||
1d1ccf4f | 996 | /* Skip P over space characters. */ |
e4976bb0 | 997 | #define SKIPSPC do { while (*p && isspace(UC(*p))) p++; } while (0) |
1d1ccf4f MW |
998 | |
999 | /* Set Q to point to the next word following P, null-terminate it, and step P | |
1000 | * past it. */ | |
e4976bb0 | 1001 | #define NEXTWORD(q) do { \ |
1002 | SKIPSPC; \ | |
1003 | q = p; \ | |
1004 | while (*p && !isspace(UC(*p))) p++; \ | |
1005 | if (*p) *p++ = 0; \ | |
1006 | } while (0) | |
1d1ccf4f MW |
1007 | |
1008 | /* Set Q to point to the next dotted-quad address, store the ending delimiter | |
1009 | * in DEL, null-terminate it, and step P past it. */ | |
9314b85a MW |
1010 | static void parse_nextaddr(char **pp, char **qq, int *del) |
1011 | { | |
1012 | char *p = *pp; | |
1013 | ||
1014 | SKIPSPC; | |
1015 | if (*p == '[') { | |
1016 | p++; SKIPSPC; | |
1017 | *qq = p; | |
1018 | p += strcspn(p, "]"); | |
1019 | if (*p) *p++ = 0; | |
1020 | *del = 0; | |
1021 | } else { | |
1022 | *qq = p; | |
1023 | while (*p && (*p == '.' || isdigit(UC(*p)))) p++; | |
1024 | *del = *p; | |
1025 | if (*p) *p++ = 0; | |
1026 | } | |
1027 | *pp = p; | |
1028 | } | |
1d1ccf4f MW |
1029 | |
1030 | /* Set Q to point to the next decimal number, store the ending delimiter in | |
1031 | * DEL, null-terminate it, and step P past it. */ | |
e4976bb0 | 1032 | #define NEXTNUMBER(q, del) do { \ |
1033 | SKIPSPC; \ | |
1034 | q = p; \ | |
1035 | while (*p && isdigit(UC(*p))) p++; \ | |
1036 | del = *p; \ | |
1037 | if (*p) *p++ = 0; \ | |
1038 | } while (0) | |
1d1ccf4f MW |
1039 | |
1040 | /* Push the character DEL back so we scan it again, unless it's zero | |
1041 | * (end-of-file). */ | |
e4976bb0 | 1042 | #define RESCAN(del) do { if (del) *--p = del; } while (0) |
1d1ccf4f MW |
1043 | |
1044 | /* Evaluate true if P is pointing to the word KW (and not some longer string | |
1045 | * of which KW is a prefix). */ | |
1046 | ||
e4976bb0 | 1047 | #define KWMATCHP(kw) (strncmp(p, kw, sizeof(kw) - 1) == 0 && \ |
1048 | !isalnum(UC(p[sizeof(kw) - 1])) && \ | |
1049 | (p += sizeof(kw) - 1)) | |
9f82ba1f | 1050 | |
1d1ccf4f MW |
1051 | /* Parse a port list, starting at *PP. Port lists have the form |
1052 | * [:LOW[-HIGH]]: if omitted, all ports are included; if HIGH is omitted, | |
1053 | * it's as if HIGH = LOW. Store LOW in *MIN, HIGH in *MAX and set *PP to the | |
1054 | * rest of the string. | |
1055 | */ | |
e4976bb0 | 1056 | static void parse_ports(char **pp, unsigned short *min, unsigned short *max) |
1057 | { | |
1058 | char *p = *pp, *q; | |
1059 | int del; | |
1060 | ||
1061 | SKIPSPC; | |
f6049fdd | 1062 | if (*p != ':') |
1063 | { *min = 0; *max = 0xffff; } | |
1064 | else { | |
e4976bb0 | 1065 | p++; |
f6049fdd | 1066 | NEXTNUMBER(q, del); *min = strtoul(q, 0, 0); RESCAN(del); |
e4976bb0 | 1067 | SKIPSPC; |
f6049fdd | 1068 | if (*p == '-') |
d83beb5c | 1069 | { p++; NEXTNUMBER(q, del); *max = strtoul(q, 0, 0); RESCAN(del); } |
f6049fdd | 1070 | else |
e4976bb0 | 1071 | *max = *min; |
1072 | } | |
1073 | *pp = p; | |
1074 | } | |
1075 | ||
006dd63f MW |
1076 | /* Parse an address range designator starting at PP and store a |
1077 | * representation of it in R. An address range designator has the form: | |
1078 | * | |
1079 | * any | local | ADDR | ADDR - ADDR | ADDR/ADDR | ADDR/INT | |
1d1ccf4f | 1080 | */ |
006dd63f | 1081 | static int parse_addrrange(char **pp, addrrange *r) |
e4976bb0 | 1082 | { |
006dd63f MW |
1083 | char *p = *pp, *q; |
1084 | int n; | |
e4976bb0 | 1085 | int del; |
006dd63f | 1086 | int af; |
e4976bb0 | 1087 | |
006dd63f MW |
1088 | SKIPSPC; |
1089 | if (KWMATCHP("any")) r->type = ANY; | |
1090 | else if (KWMATCHP("local")) r->type = LOCAL; | |
1091 | else { | |
1092 | parse_nextaddr(&p, &q, &del); | |
1093 | af = guess_address_family(q); | |
1094 | if (inet_pton(af, q, &r->u.range.min) <= 0) goto bad; | |
1095 | RESCAN(del); | |
a6d9626b | 1096 | SKIPSPC; |
006dd63f MW |
1097 | if (*p == '-') { |
1098 | p++; | |
1099 | parse_nextaddr(&p, &q, &del); | |
1100 | if (inet_pton(af, q, &r->u.range.max) <= 0) goto bad; | |
1101 | RESCAN(del); | |
1102 | } else if (*p == '/') { | |
1103 | p++; | |
1104 | NEXTNUMBER(q, del); | |
1105 | n = strtoul(q, 0, 0); | |
1106 | r->u.range.max = r->u.range.min; | |
1107 | mask_address(af, &r->u.range.min, n, 0); | |
1108 | mask_address(af, &r->u.range.max, n, 1); | |
1109 | RESCAN(del); | |
1110 | } else | |
1111 | r->u.range.max = r->u.range.min; | |
1112 | r->type = RANGE; | |
1113 | r->u.range.af = af; | |
1114 | } | |
1115 | *pp = p; | |
1116 | return (0); | |
e4976bb0 | 1117 | |
006dd63f MW |
1118 | bad: |
1119 | return (-1); | |
1120 | } | |
1121 | ||
1122 | /* Call FUNC on each individual address range in R. */ | |
1123 | static void foreach_addrrange(const addrrange *r, | |
1124 | void (*func)(int af, | |
1125 | const ipaddr *min, | |
1126 | const ipaddr *max, | |
1127 | void *p), | |
1128 | void *p) | |
1129 | { | |
1130 | ipaddr minaddr, maxaddr; | |
1131 | int i, af; | |
1132 | ||
1133 | switch (r->type) { | |
1134 | case EMPTY: | |
1135 | break; | |
1136 | case ANY: | |
9314b85a MW |
1137 | for (i = 0; address_families[i] >= 0; i++) { |
1138 | af = address_families[i]; | |
1139 | memset(&minaddr, 0, sizeof(minaddr)); | |
1140 | maxaddr = minaddr; mask_address(af, &maxaddr, 0, 1); | |
006dd63f | 1141 | func(af, &minaddr, &maxaddr, p); |
9314b85a | 1142 | } |
006dd63f MW |
1143 | break; |
1144 | case LOCAL: | |
9314b85a MW |
1145 | for (i = 0; address_families[i] >= 0; i++) { |
1146 | af = address_families[i]; | |
1147 | memset(&minaddr, 0, sizeof(minaddr)); | |
1148 | maxaddr = minaddr; mask_address(af, &maxaddr, 0, 1); | |
006dd63f MW |
1149 | func(af, &minaddr, &minaddr, p); |
1150 | func(af, &maxaddr, &maxaddr, p); | |
9314b85a | 1151 | } |
a6d9626b | 1152 | for (i = 0; i < n_local_ipaddrs; i++) { |
006dd63f MW |
1153 | func(local_ipaddrs[i].af, |
1154 | &local_ipaddrs[i].addr, &local_ipaddrs[i].addr, | |
1155 | p); | |
a6d9626b | 1156 | } |
006dd63f MW |
1157 | break; |
1158 | case RANGE: | |
1159 | func(r->u.range.af, &r->u.range.min, &r->u.range.max, p); | |
1160 | break; | |
1161 | default: | |
1162 | abort(); | |
1163 | } | |
1164 | } | |
1165 | ||
1166 | struct add_aclnode_ctx { | |
1167 | int act; | |
1168 | unsigned short minport, maxport; | |
1169 | aclnode ***tail; | |
1170 | }; | |
1171 | ||
1172 | static void add_aclnode(int af, const ipaddr *min, const ipaddr *max, | |
1173 | void *p) | |
1174 | { | |
1175 | struct add_aclnode_ctx *ctx = p; | |
1176 | aclnode *a; | |
1177 | ||
1178 | NEW(a); | |
1179 | a->act = ctx->act; | |
1180 | a->af = af; | |
1181 | a->minaddr = *min; a->maxaddr = *max; | |
1182 | a->minport = ctx->minport; a->maxport = ctx->maxport; | |
1183 | **ctx->tail = a; *ctx->tail = &a->next; | |
1184 | } | |
1185 | ||
1186 | /* Parse an ACL line. *PP points to the end of the line; *TAIL points to | |
1187 | * the list tail (i.e., the final link in the list). An ACL entry has the | |
1188 | * form +|- ADDR-RANGE PORTS | |
1189 | * where PORTS is parsed by parse_ports above; an ACL line consists of a | |
1190 | * comma-separated sequence of entries.. | |
1191 | */ | |
1192 | static void parse_acl_line(char **pp, aclnode ***tail) | |
1193 | { | |
1194 | struct add_aclnode_ctx ctx; | |
1195 | addrrange r; | |
1196 | char *p = *pp; | |
1197 | ||
1198 | ctx.tail = tail; | |
1199 | for (;;) { | |
1200 | SKIPSPC; | |
1201 | if (*p == '+') ctx.act = ALLOW; | |
1202 | else if (*p == '-') ctx.act = DENY; | |
1203 | else goto bad; | |
1204 | ||
1205 | p++; | |
1206 | if (parse_addrrange(&p, &r)) goto bad; | |
1207 | parse_ports(&p, &ctx.minport, &ctx.maxport); | |
1208 | foreach_addrrange(&r, add_aclnode, &ctx); | |
a6d9626b | 1209 | SKIPSPC; |
1210 | if (*p != ',') break; | |
1cce4a41 | 1211 | if (*p) p++; |
e4976bb0 | 1212 | } |
67fd355a | 1213 | if (*p) goto bad; |
f797ea6d | 1214 | *pp = p; |
e4976bb0 | 1215 | return; |
1216 | ||
1217 | bad: | |
e397f0bd | 1218 | D( fprintf(stderr, "noip(%d): bad acl spec (ignored)\n", getpid()); ) |
e4976bb0 | 1219 | return; |
1220 | } | |
1221 | ||
051fa2d8 MW |
1222 | /* Parse an ACL from an environment variable VAR, attaching it to the list |
1223 | * TAIL. | |
1224 | */ | |
1225 | static void parse_acl_env(const char *var, aclnode ***tail) | |
1226 | { | |
1227 | char *p, *q; | |
1228 | ||
1229 | if ((p = getenv(var)) != 0) { | |
1230 | p = q = xstrdup(p); | |
1231 | parse_acl_line(&q, tail); | |
1232 | free(p); | |
1233 | } | |
1234 | } | |
1235 | ||
7be80f86 MW |
1236 | struct add_impbind_ctx { |
1237 | int af, how; | |
1238 | ipaddr addr; | |
1239 | }; | |
1240 | ||
1241 | static void add_impbind(int af, const ipaddr *min, const ipaddr *max, | |
1242 | void *p) | |
1243 | { | |
1244 | struct add_impbind_ctx *ctx = p; | |
1245 | impbind *i; | |
1246 | ||
1247 | if (ctx->af && af != ctx->af) return; | |
1248 | NEW(i); | |
1249 | i->af = af; | |
1250 | i->how = ctx->how; | |
1251 | i->minaddr = *min; i->maxaddr = *max; | |
1252 | switch (ctx->how) { | |
1253 | case EXPLICIT: i->bindaddr = ctx->addr; | |
1254 | case SAME: break; | |
1255 | default: abort(); | |
1256 | } | |
1257 | *impbind_tail = i; impbind_tail = &i->next; | |
1258 | } | |
1259 | ||
1260 | /* Parse an implicit-bind line. An implicit-bind entry has the form | |
1261 | * ADDR-RANGE {ADDR | same} | |
1262 | */ | |
1263 | static void parse_impbind_line(char **pp) | |
1264 | { | |
1265 | struct add_impbind_ctx ctx; | |
1266 | char *p = *pp, *q; | |
1267 | addrrange r; | |
1268 | int del; | |
1269 | ||
1270 | for (;;) { | |
1271 | if (parse_addrrange(&p, &r)) goto bad; | |
1272 | SKIPSPC; | |
1273 | if (KWMATCHP("same")) { | |
1274 | ctx.how = SAME; | |
1275 | ctx.af = 0; | |
1276 | } else { | |
1277 | ctx.how = EXPLICIT; | |
1278 | parse_nextaddr(&p, &q, &del); | |
1279 | ctx.af = guess_address_family(q); | |
1280 | if (inet_pton(ctx.af, q, &ctx.addr) < 0) goto bad; | |
1281 | RESCAN(del); | |
1282 | } | |
1283 | foreach_addrrange(&r, add_impbind, &ctx); | |
1284 | SKIPSPC; | |
1285 | if (*p != ',') break; | |
1286 | if (*p) p++; | |
1287 | } | |
1288 | if (*p) goto bad; | |
1289 | *pp = p; | |
1290 | return; | |
1291 | ||
1292 | bad: | |
1293 | D( fprintf(stderr, "noip(%d): bad implicit-bind spec (ignored)\n", | |
1294 | getpid()); ) | |
1295 | return; | |
1296 | } | |
1297 | ||
1298 | /* Parse implicit-bind instructions from an environment variable VAR, | |
1299 | * attaching it to the list. | |
1300 | */ | |
1301 | static void parse_impbind_env(const char *var) | |
1302 | { | |
1303 | char *p, *q; | |
1304 | ||
1305 | if ((p = getenv(var)) != 0) { | |
1306 | p = q = xstrdup(p); | |
1307 | parse_impbind_line(&q); | |
1308 | free(p); | |
1309 | } | |
1310 | } | |
1311 | ||
1d1ccf4f | 1312 | /* Parse the autoports configuration directive. Syntax is MIN - MAX. */ |
f6049fdd | 1313 | static void parse_autoports(char **pp) |
1314 | { | |
1315 | char *p = *pp, *q; | |
1316 | unsigned x, y; | |
1317 | int del; | |
1318 | ||
1319 | SKIPSPC; | |
1320 | NEXTNUMBER(q, del); x = strtoul(q, 0, 0); RESCAN(del); | |
1321 | SKIPSPC; | |
c6569cc9 MW |
1322 | if (*p != '-') goto bad; |
1323 | p++; | |
f6049fdd | 1324 | NEXTNUMBER(q, del); y = strtoul(q, 0, 0); RESCAN(del); |
1325 | minautoport = x; maxautoport = y; | |
67fd355a | 1326 | SKIPSPC; if (*p) goto bad; |
f797ea6d | 1327 | *pp = p; |
f6049fdd | 1328 | return; |
1329 | ||
1330 | bad: | |
e397f0bd | 1331 | D( fprintf(stderr, "noip(%d): bad port range (ignored)\n", getpid()); ) |
f6049fdd | 1332 | return; |
1333 | } | |
1334 | ||
1d1ccf4f | 1335 | /* Read the configuration from the config file and environment. */ |
e4976bb0 | 1336 | static void readconfig(void) |
1337 | { | |
1338 | FILE *fp; | |
1339 | char buf[1024]; | |
1340 | size_t n; | |
f6049fdd | 1341 | char *p, *q, *cmd; |
e397f0bd | 1342 | Dpid; |
e4976bb0 | 1343 | |
a6d9626b | 1344 | parse_acl_env("NOIP_REALBIND_BEFORE", &bind_tail); |
1345 | parse_acl_env("NOIP_REALCONNECT_BEFORE", &connect_tail); | |
7be80f86 | 1346 | parse_impbind_env("NOIP_IMPBIND_BEFORE"); |
f6049fdd | 1347 | if ((p = getenv("NOIP_AUTOPORTS")) != 0) { |
1348 | p = q = xstrdup(p); | |
1349 | parse_autoports(&q); | |
1350 | free(p); | |
1351 | } | |
4ab301de | 1352 | if ((p = getenv("NOIP_CONFIG")) == 0) |
1353 | snprintf(p = buf, sizeof(buf), "%s/.noip", home()); | |
e397f0bd | 1354 | D( fprintf(stderr, "noip(%d): config file: %s\n", pid, p); ) |
4ab301de | 1355 | |
1356 | if ((fp = fopen(p, "r")) == 0) { | |
e397f0bd MW |
1357 | D( fprintf(stderr, "noip(%d): couldn't read config: %s\n", |
1358 | pid, strerror(errno)); ) | |
f6049fdd | 1359 | goto done; |
4ab301de | 1360 | } |
e4976bb0 | 1361 | while (fgets(buf, sizeof(buf), fp)) { |
1362 | n = strlen(buf); | |
1363 | p = buf; | |
1364 | ||
1365 | SKIPSPC; | |
1366 | if (!*p || *p == '#') continue; | |
1367 | while (n && isspace(UC(buf[n - 1]))) n--; | |
1368 | buf[n] = 0; | |
1369 | NEXTWORD(cmd); | |
1370 | SKIPSPC; | |
1371 | ||
1372 | if (strcmp(cmd, "socketdir") == 0) | |
1373 | sockdir = xstrdup(p); | |
1374 | else if (strcmp(cmd, "realbind") == 0) | |
1375 | parse_acl_line(&p, &bind_tail); | |
1376 | else if (strcmp(cmd, "realconnect") == 0) | |
1377 | parse_acl_line(&p, &connect_tail); | |
7be80f86 MW |
1378 | else if (strcmp(cmd, "impbind") == 0) |
1379 | parse_impbind_line(&p); | |
f6049fdd | 1380 | else if (strcmp(cmd, "autoports") == 0) |
1381 | parse_autoports(&p); | |
e4976bb0 | 1382 | else if (strcmp(cmd, "debug") == 0) |
1383 | debug = *p ? atoi(p) : 1; | |
1384 | else | |
7be80f86 | 1385 | D( fprintf(stderr, "noip(%d): bad config command %s\n", pid, cmd); ) |
e4976bb0 | 1386 | } |
1387 | fclose(fp); | |
1388 | ||
1389 | done: | |
a6d9626b | 1390 | parse_acl_env("NOIP_REALBIND", &bind_tail); |
1391 | parse_acl_env("NOIP_REALCONNECT", &connect_tail); | |
7be80f86 | 1392 | parse_impbind_env("NOIP_IMPBIND"); |
a6d9626b | 1393 | parse_acl_env("NOIP_REALBIND_AFTER", &bind_tail); |
1394 | parse_acl_env("NOIP_REALCONNECT_AFTER", &connect_tail); | |
7be80f86 | 1395 | parse_impbind_env("NOIP_IMPBIND_AFTER"); |
e4976bb0 | 1396 | *bind_tail = 0; |
1397 | *connect_tail = 0; | |
7be80f86 | 1398 | *impbind_tail = 0; |
a6d9626b | 1399 | if (!sockdir) sockdir = getenv("NOIP_SOCKETDIR"); |
e4976bb0 | 1400 | if (!sockdir) { |
1401 | snprintf(buf, sizeof(buf), "%s/noip-%s", tmpdir(), user()); | |
1402 | sockdir = xstrdup(buf); | |
1403 | } | |
e397f0bd MW |
1404 | D( fprintf(stderr, "noip(%d): socketdir: %s\n", pid, sockdir); |
1405 | fprintf(stderr, "noip(%d): autoports: %u-%u\n", | |
1406 | pid, minautoport, maxautoport); | |
1407 | fprintf(stderr, "noip(%d): realbind acl:\n", pid); | |
e4976bb0 | 1408 | dump_acl(bind_real); |
e397f0bd | 1409 | fprintf(stderr, "noip(%d): realconnect acl:\n", pid); |
7be80f86 MW |
1410 | dump_acl(connect_real); |
1411 | fprintf(stderr, "noip(%d): impbind list:\n", pid); | |
1412 | dump_impbind_list(); ) | |
e4976bb0 | 1413 | } |
1414 | ||
1d1ccf4f | 1415 | /*----- Overridden system calls -------------------------------------------*/ |
e4976bb0 | 1416 | |
dc3956b3 MW |
1417 | static void dump_syserr(long rc) |
1418 | { fprintf(stderr, " => %ld (E%d)\n", rc, errno); } | |
1419 | ||
1420 | static void dump_sysresult(long rc) | |
1421 | { | |
1422 | if (rc < 0) dump_syserr(rc); | |
1423 | else fprintf(stderr, " => %ld\n", rc); | |
1424 | } | |
1425 | ||
1426 | static void dump_addrresult(long rc, const struct sockaddr *sa, | |
1427 | socklen_t len) | |
1428 | { | |
1429 | char addrbuf[ADDRBUFSZ]; | |
1430 | ||
1431 | if (rc < 0) dump_syserr(rc); | |
1432 | else { | |
1433 | fprintf(stderr, " => %ld [%s]\n", rc, | |
1434 | present_sockaddr(sa, len, addrbuf, sizeof(addrbuf))); | |
1435 | } | |
1436 | } | |
1437 | ||
e4976bb0 | 1438 | int socket(int pf, int ty, int proto) |
1439 | { | |
dc3956b3 MW |
1440 | int sk; |
1441 | ||
1442 | D( fprintf(stderr, "noip(%d): SOCKET pf=%d, type=%d, proto=%d", | |
1443 | getpid(), pf, ty, proto); ) | |
1444 | ||
8ce11853 | 1445 | switch (pf) { |
9314b85a MW |
1446 | default: |
1447 | if (!family_known_p(pf)) { | |
dc3956b3 | 1448 | D( fprintf(stderr, " -> unknown; refuse\n"); ) |
9314b85a | 1449 | errno = EAFNOSUPPORT; |
dc3956b3 | 1450 | sk = -1; |
9314b85a | 1451 | } |
dc3956b3 | 1452 | D( fprintf(stderr, " -> inet; substitute"); ) |
8ce11853 MW |
1453 | pf = PF_UNIX; |
1454 | proto = 0; | |
dc3956b3 | 1455 | break; |
8ce11853 | 1456 | case PF_UNIX: |
41c50995 MW |
1457 | #ifdef PF_NETLINK |
1458 | case PF_NETLINK: | |
1459 | #endif | |
dc3956b3 MW |
1460 | D( fprintf(stderr, " -> safe; permit"); ) |
1461 | break; | |
e4976bb0 | 1462 | } |
dc3956b3 MW |
1463 | sk = real_socket(pf, ty, proto); |
1464 | D( dump_sysresult(sk); ) | |
1465 | return (sk); | |
e4976bb0 | 1466 | } |
1467 | ||
1468 | int socketpair(int pf, int ty, int proto, int *sk) | |
1469 | { | |
dc3956b3 MW |
1470 | int rc; |
1471 | ||
1472 | D( fprintf(stderr, "noip(%d): SOCKETPAIR pf=%d, type=%d, proto=%d", | |
1473 | getpid(), pf, ty, proto); ) | |
1474 | if (!family_known_p(pf)) | |
1475 | D( fprintf(stderr, " -> unknown; permit"); ) | |
1476 | else { | |
1477 | D( fprintf(stderr, " -> inet; substitute"); ) | |
e4976bb0 | 1478 | pf = PF_UNIX; |
1479 | proto = 0; | |
1480 | } | |
dc3956b3 MW |
1481 | rc = real_socketpair(pf, ty, proto, sk); |
1482 | D( if (rc < 0) dump_syserr(rc); | |
1483 | else fprintf(stderr, " => %d (%d, %d)\n", rc, sk[0], sk[1]); ) | |
1484 | return (rc); | |
e4976bb0 | 1485 | } |
1486 | ||
1487 | int bind(int sk, const struct sockaddr *sa, socklen_t len) | |
1488 | { | |
1489 | struct sockaddr_un sun; | |
dc3956b3 MW |
1490 | int rc; |
1491 | Dpid; | |
e4976bb0 | 1492 | |
dc3956b3 MW |
1493 | D({ char buf[ADDRBUFSZ]; |
1494 | fprintf(stderr, "noip(%d): BIND sk=%d, sa[%d]=%s", pid, | |
1495 | sk, len, present_sockaddr(sa, len, buf, sizeof(buf))); }) | |
1496 | ||
1497 | if (!family_known_p(sa->sa_family)) | |
1498 | D( fprintf(stderr, " -> unknown af; pass through"); ) | |
1499 | else { | |
1500 | D( fprintf(stderr, " -> checking...\n"); ) | |
e4976bb0 | 1501 | PRESERVING_ERRNO({ |
9314b85a | 1502 | if (acl_allows_p(bind_real, sa)) { |
86134bfe | 1503 | if (fixup_real_ip_socket(sk, sa->sa_family, 0)) |
e4976bb0 | 1504 | return (-1); |
1505 | } else { | |
4b9d1fad | 1506 | encode_inet_addr(&sun, sa, ENCF_FRESH); |
e4976bb0 | 1507 | sa = SA(&sun); |
1508 | len = SUN_LEN(&sun); | |
1509 | } | |
1510 | }); | |
dc3956b3 | 1511 | D( fprintf(stderr, "noip(%d): BIND ...", pid); ) |
e4976bb0 | 1512 | } |
dc3956b3 MW |
1513 | rc = real_bind(sk, sa, len); |
1514 | D( dump_sysresult(rc); ) | |
1515 | return (rc); | |
e4976bb0 | 1516 | } |
1517 | ||
1518 | int connect(int sk, const struct sockaddr *sa, socklen_t len) | |
1519 | { | |
1520 | struct sockaddr_un sun; | |
53390eff | 1521 | int rc; |
dc3956b3 | 1522 | Dpid; |
e4976bb0 | 1523 | |
dc3956b3 MW |
1524 | D({ char buf[ADDRBUFSZ]; |
1525 | fprintf(stderr, "noip(%d): CONNECT sk=%d, sa[%d]=%s", pid, | |
1526 | sk, len, present_sockaddr(sa, len, buf, sizeof(buf))); }) | |
1527 | ||
1528 | if (!family_known_p(sa->sa_family)) { | |
1529 | D( fprintf(stderr, " -> unknown af; pass through"); ) | |
9314b85a | 1530 | rc = real_connect(sk, sa, len); |
dc3956b3 MW |
1531 | } else { |
1532 | D( fprintf(stderr, " -> checking...\n"); ) | |
9314b85a MW |
1533 | PRESERVING_ERRNO({ |
1534 | do_implicit_bind(sk, &sa, &len, &sun); | |
1535 | }); | |
dc3956b3 | 1536 | D( fprintf(stderr, "noip(%d): CONNECT ...", pid); ) |
9314b85a MW |
1537 | rc = real_connect(sk, sa, len); |
1538 | if (rc < 0) { | |
1539 | switch (errno) { | |
1540 | case ENOENT: errno = ECONNREFUSED; break; | |
6df6f816 | 1541 | } |
9314b85a | 1542 | } |
53390eff | 1543 | } |
dc3956b3 | 1544 | D( dump_sysresult(rc); ) |
9314b85a | 1545 | return (rc); |
e4976bb0 | 1546 | } |
1547 | ||
1548 | ssize_t sendto(int sk, const void *buf, size_t len, int flags, | |
1549 | const struct sockaddr *to, socklen_t tolen) | |
1550 | { | |
1551 | struct sockaddr_un sun; | |
dc3956b3 MW |
1552 | ssize_t n; |
1553 | Dpid; | |
1554 | ||
1555 | D({ char addrbuf[ADDRBUFSZ]; | |
1556 | fprintf(stderr, "noip(%d): SENDTO sk=%d, len=%lu, flags=%d, to[%d]=%s", | |
1557 | pid, sk, (unsigned long)len, flags, tolen, | |
1558 | present_sockaddr(to, tolen, addrbuf, sizeof(addrbuf))); }) | |
e4976bb0 | 1559 | |
dc3956b3 MW |
1560 | if (!to) |
1561 | D( fprintf(stderr, " -> null address; leaving"); ) | |
1562 | else if (!family_known_p(to->sa_family)) | |
1563 | D( fprintf(stderr, " -> unknown af; pass through"); ) | |
1564 | else { | |
1565 | D( fprintf(stderr, " -> checking...\n"); ) | |
e4976bb0 | 1566 | PRESERVING_ERRNO({ |
1567 | do_implicit_bind(sk, &to, &tolen, &sun); | |
1568 | }); | |
dc3956b3 | 1569 | D( fprintf(stderr, "noip(%d): SENDTO ...", pid); ) |
e4976bb0 | 1570 | } |
dc3956b3 MW |
1571 | n = real_sendto(sk, buf, len, flags, to, tolen); |
1572 | D( dump_sysresult(n); ) | |
1573 | return (n); | |
e4976bb0 | 1574 | } |
1575 | ||
1576 | ssize_t recvfrom(int sk, void *buf, size_t len, int flags, | |
1577 | struct sockaddr *from, socklen_t *fromlen) | |
1578 | { | |
1579 | char sabuf[1024]; | |
1580 | socklen_t mylen = sizeof(sabuf); | |
1581 | ssize_t n; | |
dc3956b3 | 1582 | Dpid; |
e4976bb0 | 1583 | |
dc3956b3 MW |
1584 | D( fprintf(stderr, "noip(%d): RECVFROM sk=%d, len=%lu, flags=%d", |
1585 | pid, sk, (unsigned long)len, flags); ) | |
1586 | ||
1587 | if (!from) { | |
1588 | D( fprintf(stderr, " -> null addr; pass through"); ) | |
1589 | n = real_recvfrom(sk, buf, len, flags, 0, 0); | |
1590 | } else { | |
1591 | PRESERVING_ERRNO({ | |
1592 | n = real_recvfrom(sk, buf, len, flags, SA(sabuf), &mylen); | |
1593 | if (n >= 0) { | |
1594 | D( fprintf(stderr, " -> converting...\n"); ) | |
1595 | return_fake_name(SA(sabuf), mylen, from, fromlen); | |
1596 | D( fprintf(stderr, "noip(%d): ... RECVFROM", pid); ) | |
1597 | } | |
1598 | }); | |
1599 | } | |
1600 | D( dump_addrresult(n, from, fromlen ? *fromlen : 0); ) | |
e4976bb0 | 1601 | return (n); |
1602 | } | |
1603 | ||
1604 | ssize_t sendmsg(int sk, const struct msghdr *msg, int flags) | |
1605 | { | |
1606 | struct sockaddr_un sun; | |
dc3956b3 | 1607 | const struct sockaddr *sa = SA(msg->msg_name); |
e4976bb0 | 1608 | struct msghdr mymsg; |
dc3956b3 MW |
1609 | ssize_t n; |
1610 | Dpid; | |
e4976bb0 | 1611 | |
dc3956b3 MW |
1612 | D({ char addrbuf[ADDRBUFSZ]; |
1613 | fprintf(stderr, "noip(%d): SENDMSG sk=%d, " | |
1614 | "msg_flags=%d, msg_name[%d]=%s, ...", | |
1615 | pid, sk, msg->msg_flags, msg->msg_namelen, | |
1616 | present_sockaddr(sa, msg->msg_namelen, | |
1617 | addrbuf, sizeof(addrbuf))); }) | |
1618 | ||
1619 | if (!sa) | |
1620 | D( fprintf(stderr, " -> null address; leaving"); ) | |
1621 | else if (!family_known_p(sa->sa_family)) | |
1622 | D( fprintf(stderr, " -> unknown af; pass through"); ) | |
1623 | else { | |
1624 | D( fprintf(stderr, " -> checking...\n"); ) | |
e4976bb0 | 1625 | PRESERVING_ERRNO({ |
e4976bb0 | 1626 | mymsg = *msg; |
1627 | do_implicit_bind(sk, &sa, &mymsg.msg_namelen, &sun); | |
1628 | mymsg.msg_name = SA(sa); | |
1629 | msg = &mymsg; | |
1630 | }); | |
dc3956b3 | 1631 | D( fprintf(stderr, "noip(%d): SENDMSG ...", pid); ) |
e4976bb0 | 1632 | } |
dc3956b3 MW |
1633 | n = real_sendmsg(sk, msg, flags); |
1634 | D( dump_sysresult(n); ) | |
1635 | return (n); | |
e4976bb0 | 1636 | } |
1637 | ||
1638 | ssize_t recvmsg(int sk, struct msghdr *msg, int flags) | |
1639 | { | |
1640 | char sabuf[1024]; | |
dc3956b3 MW |
1641 | struct sockaddr *sa = SA(msg->msg_name); |
1642 | socklen_t len = msg->msg_namelen; | |
e4976bb0 | 1643 | ssize_t n; |
dc3956b3 | 1644 | Dpid; |
e4976bb0 | 1645 | |
dc3956b3 MW |
1646 | D( fprintf(stderr, "noip(%d): RECVMSG sk=%d msg_flags=%d, ...", |
1647 | pid, sk, msg->msg_flags); ) | |
1648 | ||
1649 | if (!msg->msg_name) { | |
1650 | D( fprintf(stderr, " -> null addr; pass through"); ) | |
9314b85a | 1651 | return (real_recvmsg(sk, msg, flags)); |
dc3956b3 MW |
1652 | } else { |
1653 | PRESERVING_ERRNO({ | |
1654 | msg->msg_name = sabuf; | |
1655 | msg->msg_namelen = sizeof(sabuf); | |
1656 | n = real_recvmsg(sk, msg, flags); | |
1657 | if (n >= 0) { | |
1658 | D( fprintf(stderr, " -> converting...\n"); ) | |
1659 | return_fake_name(SA(sabuf), msg->msg_namelen, sa, &len); | |
1660 | D( fprintf(stderr, "noip(%d): ... RECVMSG", pid); ) | |
1661 | } | |
1662 | msg->msg_name = sa; | |
1663 | msg->msg_namelen = len; | |
1664 | }); | |
1665 | } | |
1666 | D( dump_addrresult(n, sa, len); ) | |
e4976bb0 | 1667 | return (n); |
1668 | } | |
1669 | ||
1670 | int accept(int sk, struct sockaddr *sa, socklen_t *len) | |
1671 | { | |
1672 | char sabuf[1024]; | |
1673 | socklen_t mylen = sizeof(sabuf); | |
dc3956b3 MW |
1674 | int nsk; |
1675 | Dpid; | |
e4976bb0 | 1676 | |
dc3956b3 MW |
1677 | D( fprintf(stderr, "noip(%d): ACCEPT sk=%d", pid, sk); ) |
1678 | ||
1679 | nsk = real_accept(sk, SA(sabuf), &mylen); | |
1680 | if (nsk < 0) /* failed */; | |
1681 | else if (!sa) D( fprintf(stderr, " -> address not wanted"); ) | |
1682 | else { | |
1683 | D( fprintf(stderr, " -> converting...\n"); ) | |
1684 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1685 | D( fprintf(stderr, "noip(%d): ... ACCEPT", pid); ) | |
1686 | } | |
1687 | D( dump_addrresult(nsk, sa, len ? *len : 0); ) | |
e4976bb0 | 1688 | return (nsk); |
1689 | } | |
1690 | ||
1691 | int getsockname(int sk, struct sockaddr *sa, socklen_t *len) | |
1692 | { | |
0415c10e MW |
1693 | char sabuf[1024]; |
1694 | socklen_t mylen = sizeof(sabuf); | |
dc3956b3 MW |
1695 | int rc; |
1696 | Dpid; | |
1697 | ||
1698 | D( fprintf(stderr, "noip(%d): GETSOCKNAME sk=%d", pid, sk); ) | |
0415c10e MW |
1699 | rc = real_getsockname(sk, SA(sabuf), &mylen); |
1700 | if (rc >= 0) { | |
1701 | D( fprintf(stderr, " -> converting...\n"); ) | |
1702 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1703 | D( fprintf(stderr, "noip(%d): ... GETSOCKNAME", pid); ) | |
1704 | } | |
dc3956b3 MW |
1705 | D( dump_addrresult(rc, sa, *len); ) |
1706 | return (rc); | |
e4976bb0 | 1707 | } |
1708 | ||
1709 | int getpeername(int sk, struct sockaddr *sa, socklen_t *len) | |
1710 | { | |
0415c10e MW |
1711 | char sabuf[1024]; |
1712 | socklen_t mylen = sizeof(sabuf); | |
dc3956b3 MW |
1713 | int rc; |
1714 | Dpid; | |
1715 | ||
1716 | D( fprintf(stderr, "noip(%d): GETPEERNAME sk=%d", pid, sk); ) | |
0415c10e MW |
1717 | rc = real_getpeername(sk, SA(sabuf), &mylen); |
1718 | if (rc >= 0) { | |
1719 | D( fprintf(stderr, " -> converting...\n"); ) | |
1720 | return_fake_name(SA(sabuf), mylen, sa, len); | |
1721 | D( fprintf(stderr, "noip(%d): ... GETPEERNAME", pid); ) | |
1722 | } | |
dc3956b3 | 1723 | D( dump_addrresult(rc, sa, *len); ) |
e4976bb0 | 1724 | return (0); |
1725 | } | |
1726 | ||
1727 | int getsockopt(int sk, int lev, int opt, void *p, socklen_t *len) | |
1728 | { | |
1729 | switch (lev) { | |
e32758ea | 1730 | case IPPROTO_IP: |
f47a2b17 | 1731 | case IPPROTO_IPV6: |
e32758ea MW |
1732 | case IPPROTO_TCP: |
1733 | case IPPROTO_UDP: | |
e4976bb0 | 1734 | if (*len > 0) |
1735 | memset(p, 0, *len); | |
1736 | return (0); | |
1737 | } | |
9314b85a | 1738 | return (real_getsockopt(sk, lev, opt, p, len)); |
e4976bb0 | 1739 | } |
1740 | ||
1741 | int setsockopt(int sk, int lev, int opt, const void *p, socklen_t len) | |
1742 | { | |
1743 | switch (lev) { | |
e32758ea | 1744 | case IPPROTO_IP: |
f47a2b17 | 1745 | case IPPROTO_IPV6: |
e32758ea MW |
1746 | case IPPROTO_TCP: |
1747 | case IPPROTO_UDP: | |
e4976bb0 | 1748 | return (0); |
1749 | } | |
1750 | switch (opt) { | |
1751 | case SO_BINDTODEVICE: | |
1752 | case SO_ATTACH_FILTER: | |
1753 | case SO_DETACH_FILTER: | |
1754 | return (0); | |
1755 | } | |
9314b85a | 1756 | return (real_setsockopt(sk, lev, opt, p, len)); |
e4976bb0 | 1757 | } |
1758 | ||
658c1774 MW |
1759 | int ioctl(int fd, unsigned long op, ...) |
1760 | { | |
1761 | va_list ap; | |
1762 | void *arg; | |
1763 | int sk; | |
1764 | int rc; | |
1765 | ||
1766 | va_start(ap, op); | |
1767 | arg = va_arg(ap, void *); | |
1768 | ||
1769 | switch (op) { | |
1770 | case SIOCGIFADDR: | |
1771 | case SIOCGIFBRDADDR: | |
1772 | case SIOCGIFDSTADDR: | |
1773 | case SIOCGIFNETMASK: | |
1774 | PRESERVING_ERRNO({ | |
1775 | if (fixup_real_ip_socket(fd, AF_INET, &sk)) goto real; | |
1776 | }); | |
1777 | rc = real_ioctl(sk, op, arg); | |
1778 | PRESERVING_ERRNO({ close(sk); }); | |
1779 | break; | |
1780 | default: | |
1781 | real: | |
1782 | rc = real_ioctl(fd, op, arg); | |
1783 | break; | |
1784 | } | |
1785 | va_end(ap); | |
1786 | return (rc); | |
1787 | } | |
1788 | ||
1d1ccf4f | 1789 | /*----- Initialization ----------------------------------------------------*/ |
e4976bb0 | 1790 | |
1d1ccf4f | 1791 | /* Clean up the socket directory, deleting stale sockets. */ |
e4976bb0 | 1792 | static void cleanup_sockdir(void) |
1793 | { | |
1794 | DIR *dir; | |
1795 | struct dirent *d; | |
9314b85a | 1796 | address addr; |
e4976bb0 | 1797 | struct sockaddr_un sun; |
3ef1fec9 | 1798 | struct stat st; |
e397f0bd | 1799 | Dpid; |
e4976bb0 | 1800 | |
9314b85a | 1801 | if ((dir = opendir(sockdir)) == 0) return; |
4ab301de | 1802 | sun.sun_family = AF_UNIX; |
e4976bb0 | 1803 | while ((d = readdir(dir)) != 0) { |
1804 | if (d->d_name[0] == '.') continue; | |
1805 | snprintf(sun.sun_path, sizeof(sun.sun_path), | |
1806 | "%s/%s", sockdir, d->d_name); | |
9314b85a | 1807 | if (decode_inet_addr(&addr.sa, 0, &sun, SUN_LEN(&sun)) || |
3ef1fec9 | 1808 | stat(sun.sun_path, &st) || |
4ab301de | 1809 | !S_ISSOCK(st.st_mode)) { |
e397f0bd MW |
1810 | D( fprintf(stderr, "noip(%d): ignoring unknown socketdir entry `%s'\n", |
1811 | pid, sun.sun_path); ) | |
3ef1fec9 | 1812 | continue; |
4ab301de | 1813 | } |
e4976bb0 | 1814 | if (unix_socket_status(&sun, 0) == STALE) { |
e397f0bd MW |
1815 | D( fprintf(stderr, "noip(%d): clearing away stale socket %s\n", |
1816 | pid, d->d_name); ) | |
e4976bb0 | 1817 | unlink(sun.sun_path); |
1818 | } | |
1819 | } | |
1820 | closedir(dir); | |
1821 | } | |
1822 | ||
1d1ccf4f MW |
1823 | /* Find the addresses attached to local network interfaces, and remember them |
1824 | * in a table. | |
1825 | */ | |
e4976bb0 | 1826 | static void get_local_ipaddrs(void) |
1827 | { | |
9f1396d9 | 1828 | struct ifaddrs *ifa_head, *ifa; |
9314b85a | 1829 | ipaddr a; |
e4976bb0 | 1830 | int i; |
e397f0bd | 1831 | Dpid; |
e4976bb0 | 1832 | |
e397f0bd | 1833 | D( fprintf(stderr, "noip(%d): fetching local addresses...\n", pid); ) |
9f1396d9 MW |
1834 | if (getifaddrs(&ifa_head)) { perror("getifaddrs"); return; } |
1835 | for (n_local_ipaddrs = 0, ifa = ifa_head; | |
1836 | n_local_ipaddrs < MAX_LOCAL_IPADDRS && ifa; | |
1837 | ifa = ifa->ifa_next) { | |
9314b85a | 1838 | if (!ifa->ifa_addr || !family_known_p(ifa->ifa_addr->sa_family)) |
e4976bb0 | 1839 | continue; |
9314b85a MW |
1840 | ipaddr_from_sockaddr(&a, ifa->ifa_addr); |
1841 | D({ char buf[ADDRBUFSZ]; | |
e397f0bd MW |
1842 | fprintf(stderr, "noip(%d): local addr %s = %s", pid, |
1843 | ifa->ifa_name, | |
9314b85a MW |
1844 | inet_ntop(ifa->ifa_addr->sa_family, &a, |
1845 | buf, sizeof(buf))); }) | |
9f1396d9 | 1846 | for (i = 0; i < n_local_ipaddrs; i++) { |
9314b85a MW |
1847 | if (ifa->ifa_addr->sa_family == local_ipaddrs[i].af && |
1848 | ipaddr_equal_p(local_ipaddrs[i].af, &a, &local_ipaddrs[i].addr)) { | |
9f1396d9 MW |
1849 | D( fprintf(stderr, " (duplicate)\n"); ) |
1850 | goto skip; | |
1851 | } | |
1852 | } | |
1853 | D( fprintf(stderr, "\n"); ) | |
9314b85a MW |
1854 | local_ipaddrs[n_local_ipaddrs].af = ifa->ifa_addr->sa_family; |
1855 | local_ipaddrs[n_local_ipaddrs].addr = a; | |
9f1396d9 MW |
1856 | n_local_ipaddrs++; |
1857 | skip:; | |
e4976bb0 | 1858 | } |
9f1396d9 | 1859 | freeifaddrs(ifa_head); |
e4976bb0 | 1860 | } |
1861 | ||
1d1ccf4f | 1862 | /* Print the given message to standard error. Avoids stdio. */ |
72d85cdb | 1863 | static void printerr(const char *p) |
65f3786c | 1864 | { if (write(STDERR_FILENO, p, strlen(p))) ; } |
3ef1fec9 | 1865 | |
1d1ccf4f | 1866 | /* Create the socket directory, being careful about permissions. */ |
3ef1fec9 | 1867 | static void create_sockdir(void) |
1868 | { | |
1869 | struct stat st; | |
1870 | ||
b514afdd | 1871 | if (lstat(sockdir, &st)) { |
3ef1fec9 | 1872 | if (errno == ENOENT) { |
1873 | if (mkdir(sockdir, 0700)) { | |
1874 | perror("noip: creating socketdir"); | |
1875 | exit(127); | |
1876 | } | |
b514afdd | 1877 | if (!lstat(sockdir, &st)) |
3ef1fec9 | 1878 | goto check; |
1879 | } | |
1880 | perror("noip: checking socketdir"); | |
1881 | exit(127); | |
1882 | } | |
1883 | check: | |
1884 | if (!S_ISDIR(st.st_mode)) { | |
1885 | printerr("noip: bad socketdir: not a directory\n"); | |
1886 | exit(127); | |
1887 | } | |
1888 | if (st.st_uid != uid) { | |
1889 | printerr("noip: bad socketdir: not owner\n"); | |
1890 | exit(127); | |
1891 | } | |
1892 | if (st.st_mode & 077) { | |
1893 | printerr("noip: bad socketdir: not private\n"); | |
1894 | exit(127); | |
1895 | } | |
1896 | } | |
1897 | ||
1d1ccf4f MW |
1898 | /* Initialization function. */ |
1899 | static void setup(void) __attribute__((constructor)); | |
e4976bb0 | 1900 | static void setup(void) |
1901 | { | |
1902 | PRESERVING_ERRNO({ | |
1903 | char *p; | |
1904 | ||
1905 | import(); | |
3ef1fec9 | 1906 | uid = geteuid(); |
e4976bb0 | 1907 | if ((p = getenv("NOIP_DEBUG")) && atoi(p)) |
1908 | debug = 1; | |
1909 | get_local_ipaddrs(); | |
1910 | readconfig(); | |
3ef1fec9 | 1911 | create_sockdir(); |
e4976bb0 | 1912 | cleanup_sockdir(); |
1913 | }); | |
1914 | } | |
1d1ccf4f MW |
1915 | |
1916 | /*----- That's all, folks -------------------------------------------------*/ |