3 * Make programs use Unix-domain sockets instead of IP
5 * (c) 2008 Straylight/Edgeware
8 /*----- Licensing notice --------------------------------------------------*
10 * This file is part of the preload-hacks package.
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.
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
22 * You should have received a copy of the GNU General Public License along
23 * with preload-hacks; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
32 /*----- Header files ------------------------------------------------------*/
48 #include <sys/ioctl.h>
49 #include <sys/socket.h>
53 #include <netinet/in.h>
54 #include <arpa/inet.h>
55 #include <netinet/tcp.h>
56 #include <netinet/udp.h>
60 /*----- Data structures ---------------------------------------------------*/
62 enum { UNUSED
, STALE
, USED
}; /* Unix socket status values */
63 enum { WANT_FRESH
, WANT_EXISTING
}; /* Socket address dispositions */
64 enum { DENY
, ALLOW
}; /* ACL verdicts */
66 static int address_families
[] = { AF_INET
, AF_INET6
, -1 };
70 /* Address representations. */
71 typedef union ipaddr
{
76 /* Convenient socket address hacking. */
77 typedef union address
{
79 struct sockaddr_in sin
;
80 struct sockaddr_in6 sin6
;
83 /* Access control list nodes */
84 typedef struct aclnode
{
88 ipaddr minaddr
, maxaddr
;
89 unsigned short minport
, maxport
;
92 /* Local address records */
93 typedef struct full_ipaddr
{
97 #define MAX_LOCAL_IPADDRS 64
98 static full_ipaddr local_ipaddrs
[MAX_LOCAL_IPADDRS
];
99 static int n_local_ipaddrs
;
101 /* General configuration */
103 static char *sockdir
= 0;
104 static int debug
= 0;
105 static unsigned minautoport
= 16384, maxautoport
= 65536;
107 /* Access control lists */
108 static aclnode
*bind_real
, **bind_tail
= &bind_real
;
109 static aclnode
*connect_real
, **connect_tail
= &connect_real
;
111 /*----- Import the real versions of functions -----------------------------*/
113 /* The list of functions to immport. */
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, \
127 struct sockaddr *from, socklen_t *fromlen)) \
128 _(sendmsg, ssize_t, (int, const struct msghdr *, int)) \
129 _(recvmsg, ssize_t, (int, struct msghdr *, int)) \
130 _(ioctl, int, (int, unsigned long, ...))
132 /* Function pointers to set up. */
133 #define DECL(imp, ret, args) static ret (*real_##imp) args;
137 /* Import the system calls. */
138 static void import(void)
140 #define IMPORT(imp, ret, args) \
141 real_##imp = (ret (*)args)dlsym(RTLD_NEXT, #imp);
146 /*----- Utilities ---------------------------------------------------------*/
148 /* Socket address casts */
149 #define SA(sa) ((struct sockaddr *)(sa))
150 #define SIN(sa) ((struct sockaddr_in *)(sa))
151 #define SIN6(sa) ((struct sockaddr_in6 *)(sa))
152 #define SUN(sa) ((struct sockaddr_un *)(sa))
155 #define UC(ch) ((unsigned char)(ch))
157 /* Memory allocation */
158 #define NEW(x) ((x) = xmalloc(sizeof(*x)))
159 #define NEWV(x, n) ((x) = xmalloc(sizeof(*x) * (n)))
163 # define D(body) { if (debug) { body } }
164 # define Dpid pid_t pid = debug ? getpid() : -1
170 /* Preservation of error status */
171 #define PRESERVING_ERRNO(body) do { \
172 int _err = errno; { body } errno = _err; \
175 /* Allocate N bytes of memory; abort on failure. */
176 static void *xmalloc(size_t n
)
180 if ((p
= malloc(n
)) == 0) { perror("malloc"); exit(127); }
184 /* Allocate a copy of the null-terminated string P; abort on failure. */
185 static char *xstrdup(const char *p
)
187 size_t n
= strlen(p
) + 1;
188 char *q
= xmalloc(n
);
193 /*----- Address-type hacking ----------------------------------------------*/
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.
199 static int simple_mask_length(unsigned long m
)
203 while (m
& 1) { n
++; m
>>= 1; }
207 /* Answer whether AF is an interesting address family. */
208 static int family_known_p(int af
)
219 /* Return the socket address length for address family AF. */
220 static socklen_t
family_socklen(int af
)
223 case AF_INET
: return (sizeof(struct sockaddr_in
));
224 case AF_INET6
: return (sizeof(struct sockaddr_in6
));
229 /* Return the width of addresses of kind AF. */
230 static int address_width(int af
)
233 case AF_INET
: return 32;
234 case AF_INET6
: return 128;
239 /* If addresses A and B share a common prefix then return its length;
240 * otherwise return -1.
242 static int common_prefix_length(int af
, const ipaddr
*a
, const ipaddr
*b
)
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
));
252 const uint8_t *aa
= a
->v6
.s6_addr
, *bb
= b
->v6
.s6_addr
;
257 for (i
= 0; i
< 16 && aa
[i
] == bb
[i
]; 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);
273 /* Extract the port number (in host byte-order) from SA. */
274 static int port_from_sockaddr(const struct sockaddr
*sa
)
276 switch (sa
->sa_family
) {
277 case AF_INET
: return (ntohs(SIN(sa
)->sin_port
));
278 case AF_INET6
: return (ntohs(SIN6(sa
)->sin6_port
));
283 /* Store the port number PORT (in host byte-order) in SA. */
284 static void port_to_sockaddr(struct sockaddr
*sa
, int port
)
286 switch (sa
->sa_family
) {
287 case AF_INET
: SIN(sa
)->sin_port
= htons(port
); break;
288 case AF_INET6
: SIN6(sa
)->sin6_port
= htons(port
); break;
293 /* Extract the address part from SA and store it in A. */
294 static void ipaddr_from_sockaddr(ipaddr
*a
, const struct sockaddr
*sa
)
296 switch (sa
->sa_family
) {
297 case AF_INET
: a
->v4
= SIN(sa
)->sin_addr
; break;
298 case AF_INET6
: a
->v6
= SIN6(sa
)->sin6_addr
; break;
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
)); }
308 /* Answer whether two addresses are equal. */
309 static int ipaddr_equal_p(int af
, const ipaddr
*a
, const ipaddr
*b
)
312 case AF_INET
: return (a
->v4
.s_addr
== b
->v4
.s_addr
);
313 case AF_INET6
: return (memcmp(a
->v6
.s6_addr
, b
->v6
.s6_addr
, 16) == 0);
318 /* Answer whether the address part of SA is between A and B (inclusive). We
319 * assume that SA has the correct address family.
321 static int sockaddr_in_range_p(const struct sockaddr
*sa
,
322 const ipaddr
*a
, const ipaddr
*b
)
324 switch (sa
->sa_family
) {
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
));
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
;
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;
348 /* Fill in SA with the appropriate wildcard address. */
349 static void wildcard_address(int af
, struct sockaddr
*sa
)
353 struct sockaddr_in
*sin
= SIN(sa
);
354 memset(sin
, 0, sizeof(*sin
));
355 sin
->sin_family
= AF_INET
;
357 sin
->sin_addr
.s_addr
= INADDR_ANY
;
360 struct sockaddr_in6
*sin6
= SIN6(sa
);
361 memset(sin6
, 0, sizeof(*sin6
));
362 sin6
->sin6_family
= AF_INET6
;
364 sin6
->sin6_addr
= in6addr_any
;
365 sin6
->sin6_scope_id
= 0;
366 sin6
->sin6_flowinfo
= 0;
373 /* Mask the address A, forcing all but the top PLEN bits to zero or one
374 * according to HIGHP.
376 static void mask_address(int af
, ipaddr
*a
, int plen
, int highp
)
380 unsigned long addr
= ntohl(a
->v4
.s_addr
);
381 unsigned long mask
= plen ?
~0ul << (32 - plen
) : 0;
383 if (highp
) addr
|= ~mask
;
384 a
->v4
.s_addr
= htonl(addr
& 0xffffffff);
388 unsigned m
= (0xff << (8 - plen
%8)) & 0xff;
389 unsigned s
= highp ?
0xff : 0;
391 a
->v6
.s6_addr
[i
] = (a
->v6
.s6_addr
[i
] & m
) | (s
& ~m
);
394 for (; i
< 16; i
++) a
->v6
.s6_addr
[i
] = s
;
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).
406 static char *present_sockaddr(const struct sockaddr
*sa
, socklen_t len
,
407 char *buf
, size_t sz
)
409 #define WANT(n_) do { if (sz < (n_)) goto nospace; } while (0)
410 #define PUTC(c_) do { *buf++ = (c_); sz--; } while (0)
412 if (!sa
) return "<null-address>";
413 if (!sz
) return "<no-space-in-buffer>";
414 if (!len
) len
= family_socklen(sa
->sa_family
);
416 switch (sa
->sa_family
) {
418 struct sockaddr_un
*sun
= SUN(sa
);
419 char *p
= sun
->sun_path
;
420 size_t n
= len
- offsetof(struct sockaddr_un
, sun_path
);
428 case 0: WANT(2); PUTC('\\'); PUTC('0'); break;
429 case '\a': WANT(2); PUTC('\\'); PUTC('a'); break;
430 case '\n': WANT(2); PUTC('\\'); PUTC('n'); break;
431 case '\r': WANT(2); PUTC('\\'); PUTC('r'); break;
432 case '\t': WANT(2); PUTC('\\'); PUTC('t'); break;
433 case '\v': WANT(2); PUTC('\\'); PUTC('v'); break;
434 case '\\': WANT(2); PUTC('\\'); PUTC('\\'); break;
436 if (*p
> ' ' && *p
<= '~')
437 { WANT(1); PUTC(*p
); }
439 WANT(4); PUTC('\\'); PUTC('x');
440 PUTC((*p
>> 4)&0xf); PUTC((*p
>> 0)&0xf);
447 if (*p
!= '/') { WANT(2); PUTC('.'); PUTC('/'); }
448 while (n
&& *p
) { WANT(1); PUTC(*p
); p
++; n
--; }
452 case AF_INET
: case AF_INET6
: {
453 char addrbuf
[NI_MAXHOST
], portbuf
[NI_MAXSERV
];
454 int err
= getnameinfo(sa
, len
,
455 addrbuf
, sizeof(addrbuf
),
456 portbuf
, sizeof(portbuf
),
457 NI_NUMERICHOST
| NI_NUMERICSERV
);
459 snprintf(buf
, sz
, strchr(addrbuf
, ':') ?
"[%s]:%s" : "%s:%s",
463 snprintf(buf
, sz
, "<unknown-address-family %d>", sa
->sa_family
);
473 /* Guess the family of a textual socket address. */
474 static int guess_address_family(const char *p
)
475 { return (strchr(p
, ':') ? AF_INET6
: AF_INET
); }
477 /* Parse a socket address P and write the result to SA. */
478 static int parse_sockaddr(struct sockaddr
*sa
, const char *p
)
482 struct addrinfo
*ai
, ai_hint
= { 0 };
484 if (strlen(p
) >= sizeof(buf
) - 1) return (-1);
485 strcpy(buf
, p
); p
= buf
;
487 if ((q
= strchr(p
, ':')) == 0) return (-1);
491 if ((q
= strchr(p
, ']')) == 0) return (-1);
493 if (*q
!= ':') return (-1);
497 ai_hint
.ai_family
= AF_UNSPEC
;
498 ai_hint
.ai_socktype
= SOCK_DGRAM
;
499 ai_hint
.ai_flags
= AI_NUMERICHOST
| AI_NUMERICSERV
;
500 if (getaddrinfo(p
, q
, &ai_hint
, &ai
)) return (-1);
501 memcpy(sa
, ai
->ai_addr
, ai
->ai_addrlen
);
506 /*----- Access control lists ----------------------------------------------*/
510 /* Write to standard error a description of the ACL node A. */
511 static void dump_aclnode(const aclnode
*a
)
517 fprintf(stderr
, "noip(%d): %c ", getpid(), a
->act ?
'+' : '-');
518 plen
= common_prefix_length(a
->af
, &a
->minaddr
, &a
->maxaddr
);
519 p
= inet_ntop(a
->af
, &a
->minaddr
, buf
, sizeof(buf
));
520 fprintf(stderr
, strchr(p
, ':') ?
"[%s]" : "%s", p
);
522 p
= inet_ntop(a
->af
, &a
->maxaddr
, buf
, sizeof(buf
));
523 fprintf(stderr
, strchr(p
, ':') ?
"-[%s]" : "-%s", p
);
524 } else if (plen
< address_width(a
->af
))
525 fprintf(stderr
, "/%d", plen
);
526 if (a
->minport
!= 0 || a
->maxport
!= 0xffff) {
527 fprintf(stderr
, ":%u", (unsigned)a
->minport
);
528 if (a
->minport
!= a
->maxport
)
529 fprintf(stderr
, "-%u", (unsigned)a
->maxport
);
534 static void dump_acl(const aclnode
*a
)
538 for (; a
; a
= a
->next
) {
542 fprintf(stderr
, "noip(%d): [default policy: %s]\n", getpid(),
543 act
== ALLOW ?
"DENY" : "ALLOW");
548 /* Returns nonzero if the ACL A allows the socket address SA. */
549 static int acl_allows_p(const aclnode
*a
, const struct sockaddr
*sa
)
551 unsigned short port
= port_from_sockaddr(sa
);
555 D({ char buf
[ADDRBUFSZ
];
556 fprintf(stderr
, "noip(%d): check %s\n", pid
,
557 present_sockaddr(sa
, 0, buf
, sizeof(buf
))); })
558 for (; a
; a
= a
->next
) {
559 D( dump_aclnode(a
); )
560 if (sockaddr_in_range_p(sa
, &a
->minaddr
, &a
->maxaddr
) &&
561 a
->minport
<= port
&& port
<= a
->maxport
) {
562 D( fprintf(stderr
, "noip(%d): aha! %s\n", pid
,
563 a
->act ?
"ALLOW" : "DENY"); )
568 D( fprintf(stderr
, "noip(%d): nothing found: %s\n", pid
,
569 act ?
"DENY" : "ALLOW"); )
573 /*----- Socket address conversion -----------------------------------------*/
575 /* Return a uniformly distributed integer between MIN and MAX inclusive. */
576 static unsigned randrange(unsigned min
, unsigned max
)
580 /* It's so nice not to have to care about the quality of the generator
584 for (mask
= 1; mask
< max
; mask
= (mask
<< 1) | 1)
586 do i
= rand() & mask
; while (i
> max
);
590 /* Return the status of Unix-domain socket address SUN. Returns: UNUSED if
591 * the socket doesn't exist; USED if the path refers to an active socket, or
592 * isn't really a socket at all, or we can't tell without a careful search
593 * and QUICKP is set; or STALE if the file refers to a socket which isn't
594 * being used any more.
596 static int unix_socket_status(struct sockaddr_un
*sun
, int quickp
)
604 if (stat(sun
->sun_path
, &st
))
605 return (errno
== ENOENT ? UNUSED
: USED
);
606 if (!S_ISSOCK(st
.st_mode
) || quickp
)
609 if ((fp
= fopen("/proc/net/unix", "r")) == 0)
611 if (!fgets(buf
, sizeof(buf
), fp
)) goto done
; /* skip header */
612 len
= strlen(sun
->sun_path
);
613 while (fgets(buf
, sizeof(buf
), fp
)) {
615 if (n
>= len
+ 2 && buf
[n
- len
- 2] == ' ' && buf
[n
- 1] == '\n' &&
616 memcmp(buf
+ n
- len
- 1, sun
->sun_path
, len
) == 0)
627 /* Convert the IP address SA to a Unix-domain address SUN. Fail if the
628 * address seems already taken. If DESPARATEP then try cleaning up stale old
631 static int encode_unused_inet_addr(struct sockaddr
*sa
,
632 struct sockaddr_un
*sun
,
636 struct sockaddr_un wsun
;
640 snprintf(sun
->sun_path
, sizeof(sun
->sun_path
), "%s/%s", sockdir
,
641 present_sockaddr(sa
, 0, buf
, sizeof(buf
)));
642 if ((rc
= unix_socket_status(sun
, !desperatep
)) == USED
) return (-1);
643 else if (rc
== STALE
) unlink(sun
->sun_path
);
645 wildcard_address(sa
->sa_family
, &waddr
.sa
);
646 port_to_sockaddr(&waddr
.sa
, port_from_sockaddr(sa
));
647 snprintf(wsun
.sun_path
, sizeof(wsun
.sun_path
), "%s/%s", sockdir
,
648 present_sockaddr(&waddr
.sa
, 0, buf
, sizeof(buf
)));
649 if ((rc
= unix_socket_status(&wsun
, !desperatep
)) == USED
) return (-1);
650 else if (rc
== STALE
) unlink(wsun
.sun_path
);
655 /* Encode the Internet address SA as a Unix-domain address SUN. If WANT is
656 * WANT_FRESH, and SA's port number is zero, then we pick an arbitrary local
657 * port. Otherwise we pick the port given. There's an unpleasant hack to
658 * find servers bound to local wildcard addresses. Returns zero on success;
661 static int encode_inet_addr(struct sockaddr_un
*sun
,
662 const struct sockaddr
*sa
,
671 D( fprintf(stderr
, "noip(%d): encode %s (%s)", getpid(),
672 present_sockaddr(sa
, 0, buf
, sizeof(buf
)),
673 want
== WANT_EXISTING ?
"EXISTING" : "FRESH"); )
674 sun
->sun_family
= AF_UNIX
;
675 if (port_from_sockaddr(sa
) || want
== WANT_EXISTING
) {
676 snprintf(sun
->sun_path
, sizeof(sun
->sun_path
), "%s/%s", sockdir
,
677 present_sockaddr(sa
, 0, buf
, sizeof(buf
)));
678 rc
= unix_socket_status(sun
, 0);
679 if (rc
== STALE
) unlink(sun
->sun_path
);
680 if (rc
!= USED
&& want
== WANT_EXISTING
) {
681 wildcard_address(sa
->sa_family
, &addr
.sa
);
682 port_to_sockaddr(&addr
.sa
, port_from_sockaddr(sa
));
683 snprintf(sun
->sun_path
, sizeof(sun
->sun_path
), "%s/%s", sockdir
,
684 present_sockaddr(&addr
.sa
, 0, buf
, sizeof(buf
)));
685 if (unix_socket_status(sun
, 0) == STALE
) unlink(sun
->sun_path
);
688 copy_sockaddr(&addr
.sa
, sa
);
689 for (i
= 0; i
< 10; i
++) {
690 port_to_sockaddr(&addr
.sa
, randrange(minautoport
, maxautoport
));
691 if (!encode_unused_inet_addr(&addr
.sa
, sun
, 0)) goto found
;
693 for (desperatep
= 0; desperatep
< 2; desperatep
++) {
694 for (i
= minautoport
; i
<= maxautoport
; i
++) {
695 port_to_sockaddr(&addr
.sa
, i
);
696 if (!encode_unused_inet_addr(&addr
.sa
, sun
, 0)) goto found
;
700 D( fprintf(stderr
, " -- can't resolve\n"); )
704 D( fprintf(stderr
, " -> `%s'\n", sun
->sun_path
); )
708 /* Decode the Unix address SUN to an Internet address SIN. If AF_HINT is
709 * nonzero, an empty address (indicative of an unbound Unix-domain socket) is
710 * translated to a wildcard Internet address of the appropriate family.
711 * Returns zero on success; -1 on failure (e.g., it wasn't one of our
714 static int decode_inet_addr(struct sockaddr
*sa
, int af_hint
,
715 const struct sockaddr_un
*sun
,
719 size_t n
= strlen(sockdir
), nn
;
722 if (!sa
) sa
= &addr
.sa
;
723 if (sun
->sun_family
!= AF_UNIX
) return (-1);
724 if (len
> sizeof(*sun
)) return (-1);
725 ((char *)sun
)[len
] = 0;
726 nn
= strlen(sun
->sun_path
);
727 D( fprintf(stderr
, "noip(%d): decode `%s'", getpid(), sun
->sun_path
); )
728 if (af_hint
&& !sun
->sun_path
[0]) {
729 wildcard_address(af_hint
, sa
);
730 D( fprintf(stderr
, " -- unbound socket\n"); )
733 if (nn
< n
+ 1 || nn
- n
>= sizeof(buf
) || sun
->sun_path
[n
] != '/' ||
734 memcmp(sun
->sun_path
, sockdir
, n
) != 0) {
735 D( fprintf(stderr
, " -- not one of ours\n"); )
738 if (parse_sockaddr(sa
, sun
->sun_path
+ n
+ 1)) return (-1);
739 D( fprintf(stderr
, " -> %s\n",
740 present_sockaddr(sa
, 0, buf
, sizeof(buf
))); )
744 /* SK is (or at least might be) a Unix-domain socket we created when an
745 * Internet socket was asked for. We've decided it should be an Internet
746 * socket after all, with family AF_HINT, so convert it. If TMP is not null,
747 * then don't replace the existing descriptor: store the new socket in *TMP
750 static int fixup_real_ip_socket(int sk
, int af_hint
, int *tmp
)
755 struct sockaddr_un sun
;
768 _(LINGER, struct linger) \
771 _(RCVTIMEO, struct timeval) \
772 _(SNDTIMEO, struct timeval)
775 if (real_getsockname(sk
, SA(&sun
), &len
))
777 if (decode_inet_addr(&addr
.sa
, af_hint
, &sun
, len
))
778 return (0); /* Not one of ours */
780 if (real_getsockopt(sk
, SOL_SOCKET
, SO_TYPE
, &type
, &len
) < 0 ||
781 (nsk
= real_socket(addr
.sa
.sa_family
, type
, 0)) < 0)
783 #define FIX(opt, ty) do { \
786 if (real_getsockopt(sk, SOL_SOCKET, SO_##opt, &ov_, &len) < 0 || \
787 real_setsockopt(nsk, SOL_SOCKET, SO_##opt, &ov_, len)) { \
797 if ((f
= fcntl(sk
, F_GETFL
)) < 0 ||
798 (fd
= fcntl(sk
, F_GETFD
)) < 0 ||
799 fcntl(nsk
, F_SETFL
, f
) < 0 ||
804 unlink(sun
.sun_path
);
806 if (fcntl(sk
, F_SETFD
, fd
) < 0) {
807 perror("noip: fixup_real_ip_socket F_SETFD");
814 /* The socket SK is about to be used to communicate with the remote address
815 * SA. Assign it a local address so that getpeername(2) does something
818 static int do_implicit_bind(int sk
, const struct sockaddr
**sa
,
819 socklen_t
*len
, struct sockaddr_un
*sun
)
822 socklen_t mylen
= sizeof(*sun
);
824 if (acl_allows_p(connect_real
, *sa
)) {
825 if (fixup_real_ip_socket(sk
, (*sa
)->sa_family
, 0)) return (-1);
827 if (real_getsockname(sk
, SA(sun
), &mylen
) < 0) return (-1);
828 if (sun
->sun_family
== AF_UNIX
) {
829 if (mylen
< sizeof(*sun
)) ((char *)sun
)[mylen
] = 0;
830 if (!sun
->sun_path
[0]) {
831 wildcard_address((*sa
)->sa_family
, &addr
.sa
);
832 encode_inet_addr(sun
, &addr
.sa
, WANT_FRESH
);
833 if (real_bind(sk
, SA(sun
), SUN_LEN(sun
))) return (-1);
835 encode_inet_addr(sun
, *sa
, WANT_EXISTING
);
843 /* We found the real address SA, with length LEN; if it's a Unix-domain
844 * address corresponding to a fake socket, convert it to cover up the
845 * deception. Whatever happens, put the result at FAKE and store its length
848 static void return_fake_name(struct sockaddr
*sa
, socklen_t len
,
849 struct sockaddr
*fake
, socklen_t
*fakelen
)
854 if (sa
->sa_family
== AF_UNIX
&&
855 !decode_inet_addr(&addr
.sa
, 0, SUN(sa
), len
)) {
857 len
= family_socklen(addr
.sa
.sa_family
);
860 if (len
> *fakelen
) len
= *fakelen
;
861 if (len
> 0) memcpy(fake
, sa
, len
);
865 /*----- Configuration -----------------------------------------------------*/
867 /* Return the process owner's home directory. */
868 static char *home(void)
873 if (getuid() == uid
&&
874 (p
= getenv("HOME")) != 0)
876 else if ((pw
= getpwuid(uid
)) != 0)
882 /* Return a good temporary directory to use. */
883 static char *tmpdir(void)
887 if ((p
= getenv("TMPDIR")) != 0) return (p
);
888 else if ((p
= getenv("TMP")) != 0) return (p
);
889 else return ("/tmp");
892 /* Return the user's name, or at least something distinctive. */
893 static char *user(void)
899 if ((p
= getenv("USER")) != 0) return (p
);
900 else if ((p
= getenv("LOGNAME")) != 0) return (p
);
901 else if ((pw
= getpwuid(uid
)) != 0) return (pw
->pw_name
);
903 snprintf(buf
, sizeof(buf
), "uid-%lu", (unsigned long)uid
);
908 /* Skip P over space characters. */
909 #define SKIPSPC do { while (*p && isspace(UC(*p))) p++; } while (0)
911 /* Set Q to point to the next word following P, null-terminate it, and step P
913 #define NEXTWORD(q) do { \
916 while (*p && !isspace(UC(*p))) p++; \
920 /* Set Q to point to the next dotted-quad address, store the ending delimiter
921 * in DEL, null-terminate it, and step P past it. */
922 static void parse_nextaddr(char **pp
, char **qq
, int *del
)
930 p
+= strcspn(p
, "]");
935 while (*p
&& (*p
== '.' || isdigit(UC(*p
)))) p
++;
942 /* Set Q to point to the next decimal number, store the ending delimiter in
943 * DEL, null-terminate it, and step P past it. */
944 #define NEXTNUMBER(q, del) do { \
947 while (*p && isdigit(UC(*p))) p++; \
952 /* Push the character DEL back so we scan it again, unless it's zero
954 #define RESCAN(del) do { if (del) *--p = del; } while (0)
956 /* Evaluate true if P is pointing to the word KW (and not some longer string
957 * of which KW is a prefix). */
959 #define KWMATCHP(kw) (strncmp(p, kw, sizeof(kw) - 1) == 0 && \
960 !isalnum(UC(p[sizeof(kw) - 1])) && \
961 (p += sizeof(kw) - 1))
963 /* Parse a port list, starting at *PP. Port lists have the form
964 * [:LOW[-HIGH]]: if omitted, all ports are included; if HIGH is omitted,
965 * it's as if HIGH = LOW. Store LOW in *MIN, HIGH in *MAX and set *PP to the
966 * rest of the string.
968 static void parse_ports(char **pp
, unsigned short *min
, unsigned short *max
)
975 { *min
= 0; *max
= 0xffff; }
978 NEXTNUMBER(q
, del
); *min
= strtoul(q
, 0, 0); RESCAN(del
);
981 { p
++; NEXTNUMBER(q
, del
); *max
= strtoul(q
, 0, 0); RESCAN(del
); }
988 /* Make a new ACL node. ACT is the verdict; AF is the address family;
989 * MINADDR and MAXADDR are the ranges on IP addresses; MINPORT and MAXPORT
990 * are the ranges on port numbers; TAIL is the list tail to attach the new
993 #define ACLNODE(tail_, act_, \
994 af_, minaddr_, maxaddr_, minport_, maxport_) do { \
999 a_->minaddr = (minaddr_); a_->maxaddr = (maxaddr_); \
1000 a_->minport = (minport_); a_->maxport = (maxport_); \
1001 *tail_ = a_; tail_ = &a_->next; \
1004 /* Parse an ACL line. *PP points to the end of the line; *TAIL points to
1005 * the list tail (i.e., the final link in the list). An ACL entry has the
1006 * form +|- [any | local | ADDR | ADDR - ADDR | ADDR/ADDR | ADDR/INT] PORTS
1007 * where PORTS is parsed by parse_ports above; an ACL line consists of a
1008 * comma-separated sequence of entries..
1010 static void parse_acl_line(char **pp
, aclnode
***tail
)
1012 ipaddr minaddr
, maxaddr
;
1013 unsigned short minport
, maxport
;
1022 if (*p
== '+') act
= ALLOW
;
1023 else if (*p
== '-') act
= DENY
;
1028 if (KWMATCHP("any")) {
1029 parse_ports(&p
, &minport
, &maxport
);
1030 for (i
= 0; address_families
[i
] >= 0; i
++) {
1031 af
= address_families
[i
];
1032 memset(&minaddr
, 0, sizeof(minaddr
));
1033 maxaddr
= minaddr
; mask_address(af
, &maxaddr
, 0, 1);
1034 ACLNODE(*tail
, act
, af
, minaddr
, maxaddr
, minport
, maxport
);
1036 } else if (KWMATCHP("local")) {
1037 parse_ports(&p
, &minport
, &maxport
);
1038 for (i
= 0; address_families
[i
] >= 0; i
++) {
1039 af
= address_families
[i
];
1040 memset(&minaddr
, 0, sizeof(minaddr
));
1041 maxaddr
= minaddr
; mask_address(af
, &maxaddr
, 0, 1);
1042 ACLNODE(*tail
, act
, af
, minaddr
, minaddr
, minport
, maxport
);
1043 ACLNODE(*tail
, act
, af
, maxaddr
, maxaddr
, minport
, maxport
);
1045 for (i
= 0; i
< n_local_ipaddrs
; i
++) {
1046 ACLNODE(*tail
, act
, local_ipaddrs
[i
].af
,
1047 local_ipaddrs
[i
].addr
, local_ipaddrs
[i
].addr
,
1051 parse_nextaddr(&p
, &q
, &del
);
1052 af
= guess_address_family(q
);
1053 if (inet_pton(af
, q
, &minaddr
) <= 0) goto bad
;
1058 parse_nextaddr(&p
, &q
, &del
);
1059 if (inet_pton(af
, q
, &maxaddr
) <= 0) goto bad
;
1061 } else if (*p
== '/') {
1064 n
= strtoul(q
, 0, 0);
1066 mask_address(af
, &minaddr
, n
, 0);
1067 mask_address(af
, &maxaddr
, n
, 1);
1071 parse_ports(&p
, &minport
, &maxport
);
1072 ACLNODE(*tail
, act
, af
, minaddr
, maxaddr
, minport
, maxport
);
1075 if (*p
!= ',') break;
1083 D( fprintf(stderr
, "noip(%d): bad acl spec (ignored)\n", getpid()); )
1087 /* Parse an ACL from an environment variable VAR, attaching it to the list
1090 static void parse_acl_env(const char *var
, aclnode
***tail
)
1094 if ((p
= getenv(var
)) != 0) {
1096 parse_acl_line(&q
, tail
);
1101 /* Parse the autoports configuration directive. Syntax is MIN - MAX. */
1102 static void parse_autoports(char **pp
)
1109 NEXTNUMBER(q
, del
); x
= strtoul(q
, 0, 0); RESCAN(del
);
1111 if (*p
!= '-') goto bad
; p
++;
1112 NEXTNUMBER(q
, del
); y
= strtoul(q
, 0, 0); RESCAN(del
);
1113 minautoport
= x
; maxautoport
= y
;
1114 SKIPSPC
; if (*p
) goto bad
;
1119 D( fprintf(stderr
, "noip(%d): bad port range (ignored)\n", getpid()); )
1123 /* Read the configuration from the config file and environment. */
1124 static void readconfig(void)
1132 parse_acl_env("NOIP_REALBIND_BEFORE", &bind_tail
);
1133 parse_acl_env("NOIP_REALCONNECT_BEFORE", &connect_tail
);
1134 if ((p
= getenv("NOIP_AUTOPORTS")) != 0) {
1136 parse_autoports(&q
);
1139 if ((p
= getenv("NOIP_CONFIG")) == 0)
1140 snprintf(p
= buf
, sizeof(buf
), "%s/.noip", home());
1141 D( fprintf(stderr
, "noip(%d): config file: %s\n", pid
, p
); )
1143 if ((fp
= fopen(p
, "r")) == 0) {
1144 D( fprintf(stderr
, "noip(%d): couldn't read config: %s\n",
1145 pid
, strerror(errno
)); )
1148 while (fgets(buf
, sizeof(buf
), fp
)) {
1153 if (!*p
|| *p
== '#') continue;
1154 while (n
&& isspace(UC(buf
[n
- 1]))) n
--;
1159 if (strcmp(cmd
, "socketdir") == 0)
1160 sockdir
= xstrdup(p
);
1161 else if (strcmp(cmd
, "realbind") == 0)
1162 parse_acl_line(&p
, &bind_tail
);
1163 else if (strcmp(cmd
, "realconnect") == 0)
1164 parse_acl_line(&p
, &connect_tail
);
1165 else if (strcmp(cmd
, "autoports") == 0)
1166 parse_autoports(&p
);
1167 else if (strcmp(cmd
, "debug") == 0)
1168 debug
= *p ?
atoi(p
) : 1;
1170 D( fprintf(stderr
, "noip: bad config command %s\n", cmd
); )
1175 parse_acl_env("NOIP_REALBIND", &bind_tail
);
1176 parse_acl_env("NOIP_REALCONNECT", &connect_tail
);
1177 parse_acl_env("NOIP_REALBIND_AFTER", &bind_tail
);
1178 parse_acl_env("NOIP_REALCONNECT_AFTER", &connect_tail
);
1181 if (!sockdir
) sockdir
= getenv("NOIP_SOCKETDIR");
1183 snprintf(buf
, sizeof(buf
), "%s/noip-%s", tmpdir(), user());
1184 sockdir
= xstrdup(buf
);
1186 D( fprintf(stderr
, "noip(%d): socketdir: %s\n", pid
, sockdir
);
1187 fprintf(stderr
, "noip(%d): autoports: %u-%u\n",
1188 pid
, minautoport
, maxautoport
);
1189 fprintf(stderr
, "noip(%d): realbind acl:\n", pid
);
1190 dump_acl(bind_real
);
1191 fprintf(stderr
, "noip(%d): realconnect acl:\n", pid
);
1192 dump_acl(connect_real
); )
1195 /*----- Overridden system calls -------------------------------------------*/
1197 static void dump_syserr(long rc
)
1198 { fprintf(stderr
, " => %ld (E%d)\n", rc
, errno
); }
1200 static void dump_sysresult(long rc
)
1202 if (rc
< 0) dump_syserr(rc
);
1203 else fprintf(stderr
, " => %ld\n", rc
);
1206 static void dump_addrresult(long rc
, const struct sockaddr
*sa
,
1209 char addrbuf
[ADDRBUFSZ
];
1211 if (rc
< 0) dump_syserr(rc
);
1213 fprintf(stderr
, " => %ld [%s]\n", rc
,
1214 present_sockaddr(sa
, len
, addrbuf
, sizeof(addrbuf
)));
1218 int socket(int pf
, int ty
, int proto
)
1222 D( fprintf(stderr
, "noip(%d): SOCKET pf=%d, type=%d, proto=%d",
1223 getpid(), pf
, ty
, proto
); )
1227 if (!family_known_p(pf
)) {
1228 D( fprintf(stderr
, " -> unknown; refuse\n"); )
1229 errno
= EAFNOSUPPORT
;
1232 D( fprintf(stderr
, " -> inet; substitute"); )
1240 D( fprintf(stderr
, " -> safe; permit"); )
1243 sk
= real_socket(pf
, ty
, proto
);
1244 D( dump_sysresult(sk
); )
1248 int socketpair(int pf
, int ty
, int proto
, int *sk
)
1252 D( fprintf(stderr
, "noip(%d): SOCKETPAIR pf=%d, type=%d, proto=%d",
1253 getpid(), pf
, ty
, proto
); )
1254 if (!family_known_p(pf
))
1255 D( fprintf(stderr
, " -> unknown; permit"); )
1257 D( fprintf(stderr
, " -> inet; substitute"); )
1261 rc
= real_socketpair(pf
, ty
, proto
, sk
);
1262 D( if (rc
< 0) dump_syserr(rc
);
1263 else fprintf(stderr
, " => %d (%d, %d)\n", rc
, sk
[0], sk
[1]); )
1267 int bind(int sk
, const struct sockaddr
*sa
, socklen_t len
)
1269 struct sockaddr_un sun
;
1273 D({ char buf
[ADDRBUFSZ
];
1274 fprintf(stderr
, "noip(%d): BIND sk=%d, sa[%d]=%s", pid
,
1275 sk
, len
, present_sockaddr(sa
, len
, buf
, sizeof(buf
))); })
1277 if (!family_known_p(sa
->sa_family
))
1278 D( fprintf(stderr
, " -> unknown af; pass through"); )
1280 D( fprintf(stderr
, " -> checking...\n"); )
1282 if (acl_allows_p(bind_real
, sa
)) {
1283 if (fixup_real_ip_socket(sk
, sa
->sa_family
, 0))
1286 encode_inet_addr(&sun
, sa
, WANT_FRESH
);
1288 len
= SUN_LEN(&sun
);
1291 D( fprintf(stderr
, "noip(%d): BIND ...", pid
); )
1293 rc
= real_bind(sk
, sa
, len
);
1294 D( dump_sysresult(rc
); )
1298 int connect(int sk
, const struct sockaddr
*sa
, socklen_t len
)
1300 struct sockaddr_un sun
;
1304 D({ char buf
[ADDRBUFSZ
];
1305 fprintf(stderr
, "noip(%d): CONNECT sk=%d, sa[%d]=%s", pid
,
1306 sk
, len
, present_sockaddr(sa
, len
, buf
, sizeof(buf
))); })
1308 if (!family_known_p(sa
->sa_family
)) {
1309 D( fprintf(stderr
, " -> unknown af; pass through"); )
1310 rc
= real_connect(sk
, sa
, len
);
1312 D( fprintf(stderr
, " -> checking...\n"); )
1314 do_implicit_bind(sk
, &sa
, &len
, &sun
);
1316 D( fprintf(stderr
, "noip(%d): CONNECT ...", pid
); )
1317 rc
= real_connect(sk
, sa
, len
);
1320 case ENOENT
: errno
= ECONNREFUSED
; break;
1324 D( dump_sysresult(rc
); )
1328 ssize_t
sendto(int sk
, const void *buf
, size_t len
, int flags
,
1329 const struct sockaddr
*to
, socklen_t tolen
)
1331 struct sockaddr_un sun
;
1335 D({ char addrbuf
[ADDRBUFSZ
];
1336 fprintf(stderr
, "noip(%d): SENDTO sk=%d, len=%lu, flags=%d, to[%d]=%s",
1337 pid
, sk
, (unsigned long)len
, flags
, tolen
,
1338 present_sockaddr(to
, tolen
, addrbuf
, sizeof(addrbuf
))); })
1341 D( fprintf(stderr
, " -> null address; leaving"); )
1342 else if (!family_known_p(to
->sa_family
))
1343 D( fprintf(stderr
, " -> unknown af; pass through"); )
1345 D( fprintf(stderr
, " -> checking...\n"); )
1347 do_implicit_bind(sk
, &to
, &tolen
, &sun
);
1349 D( fprintf(stderr
, "noip(%d): SENDTO ...", pid
); )
1351 n
= real_sendto(sk
, buf
, len
, flags
, to
, tolen
);
1352 D( dump_sysresult(n
); )
1356 ssize_t
recvfrom(int sk
, void *buf
, size_t len
, int flags
,
1357 struct sockaddr
*from
, socklen_t
*fromlen
)
1360 socklen_t mylen
= sizeof(sabuf
);
1364 D( fprintf(stderr
, "noip(%d): RECVFROM sk=%d, len=%lu, flags=%d",
1365 pid
, sk
, (unsigned long)len
, flags
); )
1368 D( fprintf(stderr
, " -> null addr; pass through"); )
1369 n
= real_recvfrom(sk
, buf
, len
, flags
, 0, 0);
1372 n
= real_recvfrom(sk
, buf
, len
, flags
, SA(sabuf
), &mylen
);
1374 D( fprintf(stderr
, " -> converting...\n"); )
1375 return_fake_name(SA(sabuf
), mylen
, from
, fromlen
);
1376 D( fprintf(stderr
, "noip(%d): ... RECVFROM", pid
); )
1380 D( dump_addrresult(n
, from
, fromlen ?
*fromlen
: 0); )
1384 ssize_t
sendmsg(int sk
, const struct msghdr
*msg
, int flags
)
1386 struct sockaddr_un sun
;
1387 const struct sockaddr
*sa
= SA(msg
->msg_name
);
1388 struct msghdr mymsg
;
1392 D({ char addrbuf
[ADDRBUFSZ
];
1393 fprintf(stderr
, "noip(%d): SENDMSG sk=%d, "
1394 "msg_flags=%d, msg_name[%d]=%s, ...",
1395 pid
, sk
, msg
->msg_flags
, msg
->msg_namelen
,
1396 present_sockaddr(sa
, msg
->msg_namelen
,
1397 addrbuf
, sizeof(addrbuf
))); })
1400 D( fprintf(stderr
, " -> null address; leaving"); )
1401 else if (!family_known_p(sa
->sa_family
))
1402 D( fprintf(stderr
, " -> unknown af; pass through"); )
1404 D( fprintf(stderr
, " -> checking...\n"); )
1407 do_implicit_bind(sk
, &sa
, &mymsg
.msg_namelen
, &sun
);
1408 mymsg
.msg_name
= SA(sa
);
1411 D( fprintf(stderr
, "noip(%d): SENDMSG ...", pid
); )
1413 n
= real_sendmsg(sk
, msg
, flags
);
1414 D( dump_sysresult(n
); )
1418 ssize_t
recvmsg(int sk
, struct msghdr
*msg
, int flags
)
1421 struct sockaddr
*sa
= SA(msg
->msg_name
);
1422 socklen_t len
= msg
->msg_namelen
;
1426 D( fprintf(stderr
, "noip(%d): RECVMSG sk=%d msg_flags=%d, ...",
1427 pid
, sk
, msg
->msg_flags
); )
1429 if (!msg
->msg_name
) {
1430 D( fprintf(stderr
, " -> null addr; pass through"); )
1431 return (real_recvmsg(sk
, msg
, flags
));
1434 msg
->msg_name
= sabuf
;
1435 msg
->msg_namelen
= sizeof(sabuf
);
1436 n
= real_recvmsg(sk
, msg
, flags
);
1438 D( fprintf(stderr
, " -> converting...\n"); )
1439 return_fake_name(SA(sabuf
), msg
->msg_namelen
, sa
, &len
);
1440 D( fprintf(stderr
, "noip(%d): ... RECVMSG", pid
); )
1443 msg
->msg_namelen
= len
;
1446 D( dump_addrresult(n
, sa
, len
); )
1450 int accept(int sk
, struct sockaddr
*sa
, socklen_t
*len
)
1453 socklen_t mylen
= sizeof(sabuf
);
1457 D( fprintf(stderr
, "noip(%d): ACCEPT sk=%d", pid
, sk
); )
1459 nsk
= real_accept(sk
, SA(sabuf
), &mylen
);
1460 if (nsk
< 0) /* failed */;
1461 else if (!sa
) D( fprintf(stderr
, " -> address not wanted"); )
1463 D( fprintf(stderr
, " -> converting...\n"); )
1464 return_fake_name(SA(sabuf
), mylen
, sa
, len
);
1465 D( fprintf(stderr
, "noip(%d): ... ACCEPT", pid
); )
1467 D( dump_addrresult(nsk
, sa
, len ?
*len
: 0); )
1471 int getsockname(int sk
, struct sockaddr
*sa
, socklen_t
*len
)
1476 D( fprintf(stderr
, "noip(%d): GETSOCKNAME sk=%d", pid
, sk
); )
1479 socklen_t mylen
= sizeof(sabuf
);
1480 rc
= real_getsockname(sk
, SA(sabuf
), &mylen
);
1482 D( fprintf(stderr
, " -> converting...\n"); )
1483 return_fake_name(SA(sabuf
), mylen
, sa
, len
);
1484 D( fprintf(stderr
, "noip(%d): ... GETSOCKNAME", pid
); )
1487 D( dump_addrresult(rc
, sa
, *len
); )
1491 int getpeername(int sk
, struct sockaddr
*sa
, socklen_t
*len
)
1496 D( fprintf(stderr
, "noip(%d): GETPEERNAME sk=%d", pid
, sk
); )
1499 socklen_t mylen
= sizeof(sabuf
);
1500 rc
= real_getpeername(sk
, SA(sabuf
), &mylen
);
1502 D( fprintf(stderr
, " -> converting...\n"); )
1503 return_fake_name(SA(sabuf
), mylen
, sa
, len
);
1504 D( fprintf(stderr
, "noip(%d): ... GETPEERNAME", pid
); )
1507 D( dump_addrresult(rc
, sa
, *len
); )
1511 int getsockopt(int sk
, int lev
, int opt
, void *p
, socklen_t
*len
)
1521 return (real_getsockopt(sk
, lev
, opt
, p
, len
));
1524 int setsockopt(int sk
, int lev
, int opt
, const void *p
, socklen_t len
)
1533 case SO_BINDTODEVICE
:
1534 case SO_ATTACH_FILTER
:
1535 case SO_DETACH_FILTER
:
1538 return (real_setsockopt(sk
, lev
, opt
, p
, len
));
1541 int ioctl(int fd
, unsigned long op
, ...)
1549 arg
= va_arg(ap
, void *);
1553 case SIOCGIFBRDADDR
:
1554 case SIOCGIFDSTADDR
:
1555 case SIOCGIFNETMASK
:
1557 if (fixup_real_ip_socket(fd
, AF_INET
, &sk
)) goto real
;
1559 rc
= real_ioctl(sk
, op
, arg
);
1560 PRESERVING_ERRNO({ close(sk
); });
1564 rc
= real_ioctl(fd
, op
, arg
);
1571 /*----- Initialization ----------------------------------------------------*/
1573 /* Clean up the socket directory, deleting stale sockets. */
1574 static void cleanup_sockdir(void)
1579 struct sockaddr_un sun
;
1583 if ((dir
= opendir(sockdir
)) == 0) return;
1584 sun
.sun_family
= AF_UNIX
;
1585 while ((d
= readdir(dir
)) != 0) {
1586 if (d
->d_name
[0] == '.') continue;
1587 snprintf(sun
.sun_path
, sizeof(sun
.sun_path
),
1588 "%s/%s", sockdir
, d
->d_name
);
1589 if (decode_inet_addr(&addr
.sa
, 0, &sun
, SUN_LEN(&sun
)) ||
1590 stat(sun
.sun_path
, &st
) ||
1591 !S_ISSOCK(st
.st_mode
)) {
1592 D( fprintf(stderr
, "noip(%d): ignoring unknown socketdir entry `%s'\n",
1593 pid
, sun
.sun_path
); )
1596 if (unix_socket_status(&sun
, 0) == STALE
) {
1597 D( fprintf(stderr
, "noip(%d): clearing away stale socket %s\n",
1599 unlink(sun
.sun_path
);
1605 /* Find the addresses attached to local network interfaces, and remember them
1608 static void get_local_ipaddrs(void)
1610 struct ifaddrs
*ifa_head
, *ifa
;
1615 D( fprintf(stderr
, "noip(%d): fetching local addresses...\n", pid
); )
1616 if (getifaddrs(&ifa_head
)) { perror("getifaddrs"); return; }
1617 for (n_local_ipaddrs
= 0, ifa
= ifa_head
;
1618 n_local_ipaddrs
< MAX_LOCAL_IPADDRS
&& ifa
;
1619 ifa
= ifa
->ifa_next
) {
1620 if (!ifa
->ifa_addr
|| !family_known_p(ifa
->ifa_addr
->sa_family
))
1622 ipaddr_from_sockaddr(&a
, ifa
->ifa_addr
);
1623 D({ char buf
[ADDRBUFSZ
];
1624 fprintf(stderr
, "noip(%d): local addr %s = %s", pid
,
1626 inet_ntop(ifa
->ifa_addr
->sa_family
, &a
,
1627 buf
, sizeof(buf
))); })
1628 for (i
= 0; i
< n_local_ipaddrs
; i
++) {
1629 if (ifa
->ifa_addr
->sa_family
== local_ipaddrs
[i
].af
&&
1630 ipaddr_equal_p(local_ipaddrs
[i
].af
, &a
, &local_ipaddrs
[i
].addr
)) {
1631 D( fprintf(stderr
, " (duplicate)\n"); )
1635 D( fprintf(stderr
, "\n"); )
1636 local_ipaddrs
[n_local_ipaddrs
].af
= ifa
->ifa_addr
->sa_family
;
1637 local_ipaddrs
[n_local_ipaddrs
].addr
= a
;
1641 freeifaddrs(ifa_head
);
1644 /* Print the given message to standard error. Avoids stdio. */
1645 static void printerr(const char *p
)
1646 { if (write(STDERR_FILENO
, p
, strlen(p
))) ; }
1648 /* Create the socket directory, being careful about permissions. */
1649 static void create_sockdir(void)
1653 if (lstat(sockdir
, &st
)) {
1654 if (errno
== ENOENT
) {
1655 if (mkdir(sockdir
, 0700)) {
1656 perror("noip: creating socketdir");
1659 if (!lstat(sockdir
, &st
))
1662 perror("noip: checking socketdir");
1666 if (!S_ISDIR(st
.st_mode
)) {
1667 printerr("noip: bad socketdir: not a directory\n");
1670 if (st
.st_uid
!= uid
) {
1671 printerr("noip: bad socketdir: not owner\n");
1674 if (st
.st_mode
& 077) {
1675 printerr("noip: bad socketdir: not private\n");
1680 /* Initialization function. */
1681 static void setup(void) __attribute__((constructor
));
1682 static void setup(void)
1689 if ((p
= getenv("NOIP_DEBUG")) && atoi(p
))
1691 get_local_ipaddrs();
1698 /*----- That's all, folks -------------------------------------------------*/