1 /*
2  * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  * 3. The name of the author may not be used to endorse or promote products
13  *    derived from this software without specific prior written permission.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include "event2/event-config.h"
28 
29 #define _GNU_SOURCE
30 
31 #ifdef WIN32
32 #include <winsock2.h>
33 #include <ws2tcpip.h>
34 #define WIN32_LEAN_AND_MEAN
35 #include <windows.h>
36 #undef WIN32_LEAN_AND_MEAN
37 #include <io.h>
38 #include <tchar.h>
39 #endif
40 
41 #include <sys/types.h>
42 #ifdef _EVENT_HAVE_SYS_SOCKET_H
43 #include <sys/socket.h>
44 #endif
45 #ifdef _EVENT_HAVE_UNISTD_H
46 #include <unistd.h>
47 #endif
48 #ifdef _EVENT_HAVE_FCNTL_H
49 #include <fcntl.h>
50 #endif
51 #ifdef _EVENT_HAVE_STDLIB_H
52 #include <stdlib.h>
53 #endif
54 #include <errno.h>
55 #include <limits.h>
56 #include <stdio.h>
57 #include <string.h>
58 #ifdef _EVENT_HAVE_NETINET_IN_H
59 #include <netinet/in.h>
60 #endif
61 #ifdef _EVENT_HAVE_NETINET_IN6_H
62 #include <netinet/in6.h>
63 #endif
64 #ifdef _EVENT_HAVE_ARPA_INET_H
65 #include <arpa/inet.h>
66 #endif
67 
68 #ifndef _EVENT_HAVE_GETTIMEOFDAY
69 #include <sys/timeb.h>
70 #include <time.h>
71 #endif
72 #include <sys/stat.h>
73 
74 #include "event2/util.h"
75 #include "util-internal.h"
76 #include "log-internal.h"
77 #include "mm-internal.h"
78 
79 #include "strlcpy-internal.h"
80 #include "ipv6-internal.h"
81 
82 #ifdef WIN32
83 #define open _open
84 #define read _read
85 #define close _close
86 #define fstat _fstati64
87 #define stat _stati64
88 #define mode_t int
89 #endif
90 
91 int
evutil_open_closeonexec(const char * pathname,int flags,unsigned mode)92 evutil_open_closeonexec(const char *pathname, int flags, unsigned mode)
93 {
94 	int fd;
95 
96 #ifdef O_CLOEXEC
97 	flags |= O_CLOEXEC;
98 #endif
99 
100 	if (flags & O_CREAT)
101 		fd = open(pathname, flags, (mode_t)mode);
102 	else
103 		fd = open(pathname, flags);
104 	if (fd < 0)
105 		return -1;
106 
107 #if !defined(O_CLOEXEC) && defined(FD_CLOEXEC)
108 	if (fcntl(fd, F_SETFD, FD_CLOEXEC) < 0)
109 		return -1;
110 #endif
111 
112 	return fd;
113 }
114 
115 /**
116    Read the contents of 'filename' into a newly allocated NUL-terminated
117    string.  Set *content_out to hold this string, and *len_out to hold its
118    length (not including the appended NUL).  If 'is_binary', open the file in
119    binary mode.
120 
121    Returns 0 on success, -1 if the open fails, and -2 for all other failures.
122 
123    Used internally only; may go away in a future version.
124  */
125 int
evutil_read_file(const char * filename,char ** content_out,size_t * len_out,int is_binary)126 evutil_read_file(const char *filename, char **content_out, size_t *len_out,
127     int is_binary)
128 {
129 	int fd, r;
130 	struct stat st;
131 	char *mem;
132 	size_t read_so_far=0;
133 	int mode = O_RDONLY;
134 
135 	EVUTIL_ASSERT(content_out);
136 	EVUTIL_ASSERT(len_out);
137 	*content_out = NULL;
138 	*len_out = 0;
139 
140 #ifdef O_BINARY
141 	if (is_binary)
142 		mode |= O_BINARY;
143 #endif
144 
145 	fd = evutil_open_closeonexec(filename, mode, 0);
146 	if (fd < 0)
147 		return -1;
148 	if (fstat(fd, &st) || st.st_size < 0 ||
149 	    st.st_size > EV_SSIZE_MAX-1 ) {
150 		close(fd);
151 		return -2;
152 	}
153 	mem = mm_malloc((size_t)st.st_size + 1);
154 	if (!mem) {
155 		close(fd);
156 		return -2;
157 	}
158 	read_so_far = 0;
159 #ifdef WIN32
160 #define N_TO_READ(x) ((x) > INT_MAX) ? INT_MAX : ((int)(x))
161 #else
162 #define N_TO_READ(x) (x)
163 #endif
164 	while ((r = read(fd, mem+read_so_far, N_TO_READ(st.st_size - read_so_far))) > 0) {
165 		read_so_far += r;
166 		if (read_so_far >= (size_t)st.st_size)
167 			break;
168 		EVUTIL_ASSERT(read_so_far < (size_t)st.st_size);
169 	}
170 	close(fd);
171 	if (r < 0) {
172 		mm_free(mem);
173 		return -2;
174 	}
175 	mem[read_so_far] = 0;
176 
177 	*len_out = read_so_far;
178 	*content_out = mem;
179 	return 0;
180 }
181 
182 int
evutil_socketpair(int family,int type,int protocol,evutil_socket_t fd[2])183 evutil_socketpair(int family, int type, int protocol, evutil_socket_t fd[2])
184 {
185 #ifndef WIN32
186 	return socketpair(family, type, protocol, fd);
187 #else
188 	return evutil_ersatz_socketpair(family, type, protocol, fd);
189 #endif
190 }
191 
192 int
evutil_ersatz_socketpair(int family,int type,int protocol,evutil_socket_t fd[2])193 evutil_ersatz_socketpair(int family, int type, int protocol,
194     evutil_socket_t fd[2])
195 {
196 	/* This code is originally from Tor.  Used with permission. */
197 
198 	/* This socketpair does not work when localhost is down. So
199 	 * it's really not the same thing at all. But it's close enough
200 	 * for now, and really, when localhost is down sometimes, we
201 	 * have other problems too.
202 	 */
203 #ifdef WIN32
204 #define ERR(e) WSA##e
205 #else
206 #define ERR(e) e
207 #endif
208 	evutil_socket_t listener = -1;
209 	evutil_socket_t connector = -1;
210 	evutil_socket_t acceptor = -1;
211 	struct sockaddr_in listen_addr;
212 	struct sockaddr_in connect_addr;
213 	ev_socklen_t size;
214 	int saved_errno = -1;
215 
216 	if (protocol
217 		|| (family != AF_INET
218 #ifdef AF_UNIX
219 		    && family != AF_UNIX
220 #endif
221 		)) {
222 		EVUTIL_SET_SOCKET_ERROR(ERR(EAFNOSUPPORT));
223 		return -1;
224 	}
225 	if (!fd) {
226 		EVUTIL_SET_SOCKET_ERROR(ERR(EINVAL));
227 		return -1;
228 	}
229 
230 	listener = socket(AF_INET, type, 0);
231 	if (listener < 0)
232 		return -1;
233 	memset(&listen_addr, 0, sizeof(listen_addr));
234 	listen_addr.sin_family = AF_INET;
235 	listen_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
236 	listen_addr.sin_port = 0;	/* kernel chooses port.	 */
237 	if (bind(listener, (struct sockaddr *) &listen_addr, sizeof (listen_addr))
238 		== -1)
239 		goto tidy_up_and_fail;
240 	if (listen(listener, 1) == -1)
241 		goto tidy_up_and_fail;
242 
243 	connector = socket(AF_INET, type, 0);
244 	if (connector < 0)
245 		goto tidy_up_and_fail;
246 	/* We want to find out the port number to connect to.  */
247 	size = sizeof(connect_addr);
248 	if (getsockname(listener, (struct sockaddr *) &connect_addr, &size) == -1)
249 		goto tidy_up_and_fail;
250 	if (size != sizeof (connect_addr))
251 		goto abort_tidy_up_and_fail;
252 	if (connect(connector, (struct sockaddr *) &connect_addr,
253 				sizeof(connect_addr)) == -1)
254 		goto tidy_up_and_fail;
255 
256 	size = sizeof(listen_addr);
257 	acceptor = accept(listener, (struct sockaddr *) &listen_addr, &size);
258 	if (acceptor < 0)
259 		goto tidy_up_and_fail;
260 	if (size != sizeof(listen_addr))
261 		goto abort_tidy_up_and_fail;
262 	/* Now check we are talking to ourself by matching port and host on the
263 	   two sockets.	 */
264 	if (getsockname(connector, (struct sockaddr *) &connect_addr, &size) == -1)
265 		goto tidy_up_and_fail;
266 	if (size != sizeof (connect_addr)
267 		|| listen_addr.sin_family != connect_addr.sin_family
268 		|| listen_addr.sin_addr.s_addr != connect_addr.sin_addr.s_addr
269 		|| listen_addr.sin_port != connect_addr.sin_port)
270 		goto abort_tidy_up_and_fail;
271 	evutil_closesocket(listener);
272 	fd[0] = connector;
273 	fd[1] = acceptor;
274 
275 	return 0;
276 
277  abort_tidy_up_and_fail:
278 	saved_errno = ERR(ECONNABORTED);
279  tidy_up_and_fail:
280 	if (saved_errno < 0)
281 		saved_errno = EVUTIL_SOCKET_ERROR();
282 	if (listener != -1)
283 		evutil_closesocket(listener);
284 	if (connector != -1)
285 		evutil_closesocket(connector);
286 	if (acceptor != -1)
287 		evutil_closesocket(acceptor);
288 
289 	EVUTIL_SET_SOCKET_ERROR(saved_errno);
290 	return -1;
291 #undef ERR
292 }
293 
294 int
evutil_make_socket_nonblocking(evutil_socket_t fd)295 evutil_make_socket_nonblocking(evutil_socket_t fd)
296 {
297 #ifdef WIN32
298 	{
299 		u_long nonblocking = 1;
300 		if (ioctlsocket(fd, FIONBIO, &nonblocking) == SOCKET_ERROR) {
301 			event_sock_warn(fd, "fcntl(%d, F_GETFL)", (int)fd);
302 			return -1;
303 		}
304 	}
305 #else
306 	{
307 		int flags;
308 		if ((flags = fcntl(fd, F_GETFL, NULL)) < 0) {
309 			event_warn("fcntl(%d, F_GETFL)", fd);
310 			return -1;
311 		}
312 		if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) {
313 			event_warn("fcntl(%d, F_SETFL)", fd);
314 			return -1;
315 		}
316 	}
317 #endif
318 	return 0;
319 }
320 
321 int
evutil_make_listen_socket_reuseable(evutil_socket_t sock)322 evutil_make_listen_socket_reuseable(evutil_socket_t sock)
323 {
324 #ifndef WIN32
325 	int one = 1;
326 	/* REUSEADDR on Unix means, "don't hang on to this address after the
327 	 * listener is closed."  On Windows, though, it means "don't keep other
328 	 * processes from binding to this address while we're using it. */
329 	return setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void*) &one,
330 	    (ev_socklen_t)sizeof(one));
331 #else
332 	return 0;
333 #endif
334 }
335 
336 int
evutil_make_socket_closeonexec(evutil_socket_t fd)337 evutil_make_socket_closeonexec(evutil_socket_t fd)
338 {
339 #if !defined(WIN32) && defined(_EVENT_HAVE_SETFD)
340 	int flags;
341 	if ((flags = fcntl(fd, F_GETFD, NULL)) < 0) {
342 		event_warn("fcntl(%d, F_GETFD)", fd);
343 		return -1;
344 	}
345 	if (fcntl(fd, F_SETFD, flags | FD_CLOEXEC) == -1) {
346 		event_warn("fcntl(%d, F_SETFD)", fd);
347 		return -1;
348 	}
349 #endif
350 	return 0;
351 }
352 
353 int
evutil_closesocket(evutil_socket_t sock)354 evutil_closesocket(evutil_socket_t sock)
355 {
356 #ifndef WIN32
357 	return close(sock);
358 #else
359 	return closesocket(sock);
360 #endif
361 }
362 
363 ev_int64_t
evutil_strtoll(const char * s,char ** endptr,int base)364 evutil_strtoll(const char *s, char **endptr, int base)
365 {
366 #ifdef _EVENT_HAVE_STRTOLL
367 	return (ev_int64_t)strtoll(s, endptr, base);
368 #elif _EVENT_SIZEOF_LONG == 8
369 	return (ev_int64_t)strtol(s, endptr, base);
370 #elif defined(WIN32) && defined(_MSC_VER) && _MSC_VER < 1300
371 	/* XXXX on old versions of MS APIs, we only support base
372 	 * 10. */
373 	ev_int64_t r;
374 	if (base != 10)
375 		return 0;
376 	r = (ev_int64_t) _atoi64(s);
377 	while (isspace(*s))
378 		++s;
379 	if (*s == '-')
380 		++s;
381 	while (isdigit(*s))
382 		++s;
383 	if (endptr)
384 		*endptr = (char*) s;
385 	return r;
386 #elif defined(WIN32)
387 	return (ev_int64_t) _strtoi64(s, endptr, base);
388 #elif defined(_EVENT_SIZEOF_LONG_LONG) && _EVENT_SIZEOF_LONG_LONG == 8
389 	long long r;
390 	int n;
391 	if (base != 10 && base != 16)
392 		return 0;
393 	if (base == 10) {
394 		n = sscanf(s, "%lld", &r);
395 	} else {
396 		unsigned long long ru=0;
397 		n = sscanf(s, "%llx", &ru);
398 		if (ru > EV_INT64_MAX)
399 			return 0;
400 		r = (long long) ru;
401 	}
402 	if (n != 1)
403 		return 0;
404 	while (EVUTIL_ISSPACE(*s))
405 		++s;
406 	if (*s == '-')
407 		++s;
408 	if (base == 10) {
409 		while (EVUTIL_ISDIGIT(*s))
410 			++s;
411 	} else {
412 		while (EVUTIL_ISXDIGIT(*s))
413 			++s;
414 	}
415 	if (endptr)
416 		*endptr = (char*) s;
417 	return r;
418 #else
419 #error "I don't know how to parse 64-bit integers."
420 #endif
421 }
422 
423 #ifndef _EVENT_HAVE_GETTIMEOFDAY
424 /* No gettimeofday; this muse be windows. */
425 int
evutil_gettimeofday(struct timeval * tv,struct timezone * tz)426 evutil_gettimeofday(struct timeval *tv, struct timezone *tz)
427 {
428 	struct _timeb tb;
429 
430 	if (tv == NULL)
431 		return -1;
432 
433 	/* XXXX
434 	 * _ftime is not the greatest interface here; GetSystemTimeAsFileTime
435 	 * would give us better resolution, whereas something cobbled together
436 	 * with GetTickCount could maybe give us monotonic behavior.
437 	 *
438 	 * Either way, I think this value might be skewed to ignore the
439 	 * timezone, and just return local time.  That's not so good.
440 	 */
441 	_ftime(&tb);
442 	tv->tv_sec = (long) tb.time;
443 	tv->tv_usec = ((int) tb.millitm) * 1000;
444 	return 0;
445 }
446 #endif
447 
448 #ifdef WIN32
449 int
evutil_socket_geterror(evutil_socket_t sock)450 evutil_socket_geterror(evutil_socket_t sock)
451 {
452 	int optval, optvallen=sizeof(optval);
453 	int err = WSAGetLastError();
454 	if (err == WSAEWOULDBLOCK && sock >= 0) {
455 		if (getsockopt(sock, SOL_SOCKET, SO_ERROR, (void*)&optval,
456 					   &optvallen))
457 			return err;
458 		if (optval)
459 			return optval;
460 	}
461 	return err;
462 }
463 #endif
464 
465 /* XXX we should use an enum here. */
466 /* 2 for connection refused, 1 for connected, 0 for not yet, -1 for error. */
467 int
evutil_socket_connect(evutil_socket_t * fd_ptr,struct sockaddr * sa,int socklen)468 evutil_socket_connect(evutil_socket_t *fd_ptr, struct sockaddr *sa, int socklen)
469 {
470 	int made_fd = 0;
471 
472 	if (*fd_ptr < 0) {
473 		if ((*fd_ptr = socket(sa->sa_family, SOCK_STREAM, 0)) < 0)
474 			goto err;
475 		made_fd = 1;
476 		if (evutil_make_socket_nonblocking(*fd_ptr) < 0) {
477 			goto err;
478 		}
479 	}
480 
481 	if (connect(*fd_ptr, sa, socklen) < 0) {
482 		int e = evutil_socket_geterror(*fd_ptr);
483 		if (EVUTIL_ERR_CONNECT_RETRIABLE(e))
484 			return 0;
485 		if (EVUTIL_ERR_CONNECT_REFUSED(e))
486 			return 2;
487 		goto err;
488 	} else {
489 		return 1;
490 	}
491 
492 err:
493 	if (made_fd) {
494 		evutil_closesocket(*fd_ptr);
495 		*fd_ptr = -1;
496 	}
497 	return -1;
498 }
499 
500 /* Check whether a socket on which we called connect() is done
501    connecting. Return 1 for connected, 0 for not yet, -1 for error.  In the
502    error case, set the current socket errno to the error that happened during
503    the connect operation. */
504 int
evutil_socket_finished_connecting(evutil_socket_t fd)505 evutil_socket_finished_connecting(evutil_socket_t fd)
506 {
507 	int e;
508 	ev_socklen_t elen = sizeof(e);
509 
510 	if (getsockopt(fd, SOL_SOCKET, SO_ERROR, (void*)&e, &elen) < 0)
511 		return -1;
512 
513 	if (e) {
514 		if (EVUTIL_ERR_CONNECT_RETRIABLE(e))
515 			return 0;
516 		EVUTIL_SET_SOCKET_ERROR(e);
517 		return -1;
518 	}
519 
520 	return 1;
521 }
522 
523 #if (EVUTIL_AI_PASSIVE|EVUTIL_AI_CANONNAME|EVUTIL_AI_NUMERICHOST| \
524      EVUTIL_AI_NUMERICSERV|EVUTIL_AI_V4MAPPED|EVUTIL_AI_ALL| \
525      EVUTIL_AI_ADDRCONFIG) != \
526     (EVUTIL_AI_PASSIVE^EVUTIL_AI_CANONNAME^EVUTIL_AI_NUMERICHOST^ \
527      EVUTIL_AI_NUMERICSERV^EVUTIL_AI_V4MAPPED^EVUTIL_AI_ALL^ \
528      EVUTIL_AI_ADDRCONFIG)
529 #error "Some of our EVUTIL_AI_* flags seem to overlap with system AI_* flags"
530 #endif
531 
532 /* We sometimes need to know whether we have an ipv4 address and whether we
533    have an ipv6 address. If 'have_checked_interfaces', then we've already done
534    the test.  If 'had_ipv4_address', then it turns out we had an ipv4 address.
535    If 'had_ipv6_address', then it turns out we had an ipv6 address.   These are
536    set by evutil_check_interfaces. */
537 static int have_checked_interfaces, had_ipv4_address, had_ipv6_address;
538 
539 /* Macro: True iff the IPv4 address 'addr', in host order, is in 127.0.0.0/8
540  */
541 #define EVUTIL_V4ADDR_IS_LOCALHOST(addr) (((addr)>>24) == 127)
542 
543 /* Macro: True iff the IPv4 address 'addr', in host order, is a class D
544  * (multiclass) address.
545  */
546 #define EVUTIL_V4ADDR_IS_CLASSD(addr) ((((addr)>>24) & 0xf0) == 0xe0)
547 
548 /* Test whether we have an ipv4 interface and an ipv6 interface.  Return 0 if
549  * the test seemed successful. */
550 static int
evutil_check_interfaces(int force_recheck)551 evutil_check_interfaces(int force_recheck)
552 {
553 	const char ZEROES[] = "\x00\x00\x00\x00\x00\x00\x00\x00"
554 	    "\x00\x00\x00\x00\x00\x00\x00\x00";
555 	evutil_socket_t fd = -1;
556 	struct sockaddr_in sin, sin_out;
557 	struct sockaddr_in6 sin6, sin6_out;
558 	ev_socklen_t sin_out_len = sizeof(sin_out);
559 	ev_socklen_t sin6_out_len = sizeof(sin6_out);
560 	int r;
561 	char buf[128];
562 	if (have_checked_interfaces && !force_recheck)
563 		return 0;
564 
565 	/* To check whether we have an interface open for a given protocol, we
566 	 * try to make a UDP 'connection' to a remote host on the internet.
567 	 * We don't actually use it, so the address doesn't matter, but we
568 	 * want to pick one that keep us from using a host- or link-local
569 	 * interface. */
570 	memset(&sin, 0, sizeof(sin));
571 	sin.sin_family = AF_INET;
572 	sin.sin_port = htons(53);
573 	r = evutil_inet_pton(AF_INET, "18.244.0.188", &sin.sin_addr);
574 	EVUTIL_ASSERT(r);
575 
576 	memset(&sin6, 0, sizeof(sin6));
577 	sin6.sin6_family = AF_INET6;
578 	sin6.sin6_port = htons(53);
579 	r = evutil_inet_pton(AF_INET6, "2001:4860:b002::68", &sin6.sin6_addr);
580 	EVUTIL_ASSERT(r);
581 
582 	memset(&sin_out, 0, sizeof(sin_out));
583 	memset(&sin6_out, 0, sizeof(sin6_out));
584 
585 	/* XXX some errnos mean 'no address'; some mean 'not enough sockets'. */
586 	if ((fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) >= 0 &&
587 	    connect(fd, (struct sockaddr*)&sin, sizeof(sin)) == 0 &&
588 	    getsockname(fd, (struct sockaddr*)&sin_out, &sin_out_len) == 0) {
589 		/* We might have an IPv4 interface. */
590 		ev_uint32_t addr = ntohl(sin_out.sin_addr.s_addr);
591 		if (addr == 0 ||
592 		    EVUTIL_V4ADDR_IS_LOCALHOST(addr) ||
593 		    EVUTIL_V4ADDR_IS_CLASSD(addr)) {
594 			evutil_inet_ntop(AF_INET, &sin_out.sin_addr,
595 			    buf, sizeof(buf));
596 			/* This is a reserved, ipv4compat, ipv4map, loopback,
597 			 * link-local or unspecified address.  The host should
598 			 * never have given it to us; it could never connect
599 			 * to sin. */
600 			event_warnx("Got a strange local ipv4 address %s",buf);
601 		} else {
602 			event_debug(("Detected an IPv4 interface"));
603 			had_ipv4_address = 1;
604 		}
605 	}
606 	if (fd >= 0)
607 		evutil_closesocket(fd);
608 
609 	if ((fd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP)) >= 0 &&
610 	    connect(fd, (struct sockaddr*)&sin6, sizeof(sin6)) == 0 &&
611 	    getsockname(fd, (struct sockaddr*)&sin6_out, &sin6_out_len) == 0) {
612 		/* We might have an IPv6 interface. */
613 		const unsigned char *addr =
614 		    (unsigned char*)sin6_out.sin6_addr.s6_addr;
615 		if (!memcmp(addr, ZEROES, 8) ||
616 		    (addr[0] == 0xfe && (addr[1] & 0xc0) == 0x80)) {
617 			/* This is a reserved, ipv4compat, ipv4map, loopback,
618 			 * link-local or unspecified address.  The host should
619 			 * never have given it to us; it could never connect
620 			 * to sin6. */
621 			evutil_inet_ntop(AF_INET6, &sin6_out.sin6_addr,
622 			    buf, sizeof(buf));
623 			event_warnx("Got a strange local ipv6 address %s",buf);
624 		} else {
625 			event_debug(("Detected an IPv4 interface"));
626 			had_ipv6_address = 1;
627 		}
628 	}
629 
630 	if (fd >= 0)
631 		evutil_closesocket(fd);
632 
633 	return 0;
634 }
635 
636 /* Internal addrinfo flag.  This one is set when we allocate the addrinfo from
637  * inside libevent.  Otherwise, the built-in getaddrinfo() function allocated
638  * it, and we should trust what they said.
639  **/
640 #define EVUTIL_AI_LIBEVENT_ALLOCATED 0x80000000
641 
642 /* Helper: construct a new addrinfo containing the socket address in
643  * 'sa', which must be a sockaddr_in or a sockaddr_in6.  Take the
644  * socktype and protocol info from hints.  If they weren't set, then
645  * allocate both a TCP and a UDP addrinfo.
646  */
647 struct evutil_addrinfo *
evutil_new_addrinfo(struct sockaddr * sa,ev_socklen_t socklen,const struct evutil_addrinfo * hints)648 evutil_new_addrinfo(struct sockaddr *sa, ev_socklen_t socklen,
649     const struct evutil_addrinfo *hints)
650 {
651 	struct evutil_addrinfo *res;
652 	EVUTIL_ASSERT(hints);
653 
654 	if (hints->ai_socktype == 0 && hints->ai_protocol == 0) {
655 		/* Indecisive user! Give them a UDP and a TCP. */
656 		struct evutil_addrinfo *r1, *r2;
657 		struct evutil_addrinfo tmp;
658 		memcpy(&tmp, hints, sizeof(tmp));
659 		tmp.ai_socktype = SOCK_STREAM; tmp.ai_protocol = IPPROTO_TCP;
660 		r1 = evutil_new_addrinfo(sa, socklen, &tmp);
661 		if (!r1)
662 			return NULL;
663 		tmp.ai_socktype = SOCK_DGRAM; tmp.ai_protocol = IPPROTO_UDP;
664 		r2 = evutil_new_addrinfo(sa, socklen, &tmp);
665 		if (!r2) {
666 			evutil_freeaddrinfo(r1);
667 			return NULL;
668 		}
669 		r1->ai_next = r2;
670 		return r1;
671 	}
672 
673 	/* We're going to allocate extra space to hold the sockaddr. */
674 	res = mm_calloc(1,sizeof(struct evutil_addrinfo)+socklen);
675 	if (!res)
676 		return NULL;
677 	res->ai_addr = (struct sockaddr*)
678 	    (((char*)res) + sizeof(struct evutil_addrinfo));
679 	memcpy(res->ai_addr, sa, socklen);
680 	res->ai_addrlen = socklen;
681 	res->ai_family = sa->sa_family; /* Same or not? XXX */
682 	res->ai_flags = EVUTIL_AI_LIBEVENT_ALLOCATED;
683 	res->ai_socktype = hints->ai_socktype;
684 	res->ai_protocol = hints->ai_protocol;
685 
686 	return res;
687 }
688 
689 /* Append the addrinfo 'append' to the end of 'first', and return the start of
690  * the list.  Either element can be NULL, in which case we return the element
691  * that is not NULL. */
692 struct evutil_addrinfo *
evutil_addrinfo_append(struct evutil_addrinfo * first,struct evutil_addrinfo * append)693 evutil_addrinfo_append(struct evutil_addrinfo *first,
694     struct evutil_addrinfo *append)
695 {
696 	struct evutil_addrinfo *ai = first;
697 	if (!ai)
698 		return append;
699 	while (ai->ai_next)
700 		ai = ai->ai_next;
701 	ai->ai_next = append;
702 
703 	return first;
704 }
705 
706 static int
parse_numeric_servname(const char * servname)707 parse_numeric_servname(const char *servname)
708 {
709 	int n;
710 	char *endptr=NULL;
711 	n = (int) strtol(servname, &endptr, 10);
712 	if (n>=0 && n <= 65535 && servname[0] && endptr && !endptr[0])
713 		return n;
714 	else
715 		return -1;
716 }
717 
718 /** Parse a service name in 'servname', which can be a decimal port.
719  * Return the port number, or -1 on error.
720  */
721 static int
evutil_parse_servname(const char * servname,const char * protocol,const struct evutil_addrinfo * hints)722 evutil_parse_servname(const char *servname, const char *protocol,
723     const struct evutil_addrinfo *hints)
724 {
725 	int n = parse_numeric_servname(servname);
726 	if (n>=0)
727 		return n;
728 #if defined(_EVENT_HAVE_GETSERVBYNAME) || defined(WIN32)
729 	if (!(hints->ai_flags & EVUTIL_AI_NUMERICSERV)) {
730 		struct servent *ent = getservbyname(servname, protocol);
731 		if (ent) {
732 			return ntohs(ent->s_port);
733 		}
734 	}
735 #endif
736 	return -1;
737 }
738 
739 /* Return a string corresponding to a protocol number that we can pass to
740  * getservyname.  */
741 static const char *
evutil_unparse_protoname(int proto)742 evutil_unparse_protoname(int proto)
743 {
744 	switch (proto) {
745 	case 0:
746 		return NULL;
747 	case IPPROTO_TCP:
748 		return "tcp";
749 	case IPPROTO_UDP:
750 		return "udp";
751 #ifdef IPPROTO_SCTP
752 	case IPPROTO_SCTP:
753 		return "sctp";
754 #endif
755 	default:
756 #ifdef _EVENT_HAVE_GETPROTOBYNUMBER
757 		{
758 			struct protoent *ent = getprotobynumber(proto);
759 			if (ent)
760 				return ent->p_name;
761 		}
762 #endif
763 		return NULL;
764 	}
765 }
766 
767 static void
evutil_getaddrinfo_infer_protocols(struct evutil_addrinfo * hints)768 evutil_getaddrinfo_infer_protocols(struct evutil_addrinfo *hints)
769 {
770 	/* If we can guess the protocol from the socktype, do so. */
771 	if (!hints->ai_protocol && hints->ai_socktype) {
772 		if (hints->ai_socktype == SOCK_DGRAM)
773 			hints->ai_protocol = IPPROTO_UDP;
774 		else if (hints->ai_socktype == SOCK_STREAM)
775 			hints->ai_protocol = IPPROTO_TCP;
776 	}
777 
778 	/* Set the socktype if it isn't set. */
779 	if (!hints->ai_socktype && hints->ai_protocol) {
780 		if (hints->ai_protocol == IPPROTO_UDP)
781 			hints->ai_socktype = SOCK_DGRAM;
782 		else if (hints->ai_protocol == IPPROTO_TCP)
783 			hints->ai_socktype = SOCK_STREAM;
784 #ifdef IPPROTO_SCTP
785 		else if (hints->ai_protocol == IPPROTO_SCTP)
786 			hints->ai_socktype = SOCK_STREAM;
787 #endif
788 	}
789 }
790 
791 #if AF_UNSPEC != PF_UNSPEC
792 #error "I cannot build on a system where AF_UNSPEC != PF_UNSPEC"
793 #endif
794 
795 /** Implements the part of looking up hosts by name that's common to both
796  * the blocking and nonblocking resolver:
797  *   - Adjust 'hints' to have a reasonable socktype and protocol.
798  *   - Look up the port based on 'servname', and store it in *portnum,
799  *   - Handle the nodename==NULL case
800  *   - Handle some invalid arguments cases.
801  *   - Handle the cases where nodename is an IPv4 or IPv6 address.
802  *
803  * If we need the resolver to look up the hostname, we return
804  * EVUTIL_EAI_NEED_RESOLVE.  Otherwise, we can completely implement
805  * getaddrinfo: we return 0 or an appropriate EVUTIL_EAI_* error, and
806  * set *res as getaddrinfo would.
807  */
808 int
evutil_getaddrinfo_common(const char * nodename,const char * servname,struct evutil_addrinfo * hints,struct evutil_addrinfo ** res,int * portnum)809 evutil_getaddrinfo_common(const char *nodename, const char *servname,
810     struct evutil_addrinfo *hints, struct evutil_addrinfo **res, int *portnum)
811 {
812 	int port = 0;
813 	const char *pname;
814 
815 	if (nodename == NULL && servname == NULL)
816 		return EVUTIL_EAI_NONAME;
817 
818 	/* We only understand 3 families */
819 	if (hints->ai_family != PF_UNSPEC && hints->ai_family != PF_INET &&
820 	    hints->ai_family != PF_INET6)
821 		return EVUTIL_EAI_FAMILY;
822 
823 	evutil_getaddrinfo_infer_protocols(hints);
824 
825 	/* Look up the port number and protocol, if possible. */
826 	pname = evutil_unparse_protoname(hints->ai_protocol);
827 	if (servname) {
828 		/* XXXX We could look at the protocol we got back from
829 		 * getservbyname, but it doesn't seem too useful. */
830 		port = evutil_parse_servname(servname, pname, hints);
831 		if (port < 0) {
832 			return EVUTIL_EAI_NONAME;
833 		}
834 	}
835 
836 	/* If we have no node name, then we're supposed to bind to 'any' and
837 	 * connect to localhost. */
838 	if (nodename == NULL) {
839 		struct evutil_addrinfo *res4=NULL, *res6=NULL;
840 		if (hints->ai_family != PF_INET) { /* INET6 or UNSPEC. */
841 			struct sockaddr_in6 sin6;
842 			memset(&sin6, 0, sizeof(sin6));
843 			sin6.sin6_family = AF_INET6;
844 			sin6.sin6_port = htons(port);
845 			if (hints->ai_flags & EVUTIL_AI_PASSIVE) {
846 				/* Bind to :: */
847 			} else {
848 				/* connect to ::1 */
849 				sin6.sin6_addr.s6_addr[15] = 1;
850 			}
851 			res6 = evutil_new_addrinfo((struct sockaddr*)&sin6,
852 			    sizeof(sin6), hints);
853 			if (!res6)
854 				return EVUTIL_EAI_MEMORY;
855 		}
856 
857 		if (hints->ai_family != PF_INET6) { /* INET or UNSPEC */
858 			struct sockaddr_in sin;
859 			memset(&sin, 0, sizeof(sin));
860 			sin.sin_family = AF_INET;
861 			sin.sin_port = htons(port);
862 			if (hints->ai_flags & EVUTIL_AI_PASSIVE) {
863 				/* Bind to 0.0.0.0 */
864 			} else {
865 				/* connect to 127.0.0.1 */
866 				sin.sin_addr.s_addr = htonl(0x7f000001);
867 			}
868 			res4 = evutil_new_addrinfo((struct sockaddr*)&sin,
869 			    sizeof(sin), hints);
870 			if (!res4) {
871 				if (res6)
872 					evutil_freeaddrinfo(res6);
873 				return EVUTIL_EAI_MEMORY;
874 			}
875 		}
876 		*res = evutil_addrinfo_append(res4, res6);
877 		return 0;
878 	}
879 
880 	/* If we can, we should try to parse the hostname without resolving
881 	 * it. */
882 	/* Try ipv6. */
883 	if (hints->ai_family == PF_INET6 || hints->ai_family == PF_UNSPEC) {
884 		struct sockaddr_in6 sin6;
885 		memset(&sin6, 0, sizeof(sin6));
886 		if (1==evutil_inet_pton(AF_INET6, nodename, &sin6.sin6_addr)) {
887 			/* Got an ipv6 address. */
888 			sin6.sin6_family = AF_INET6;
889 			sin6.sin6_port = htons(port);
890 			*res = evutil_new_addrinfo((struct sockaddr*)&sin6,
891 			    sizeof(sin6), hints);
892 			if (!*res)
893 				return EVUTIL_EAI_MEMORY;
894 			return 0;
895 		}
896 	}
897 
898 	/* Try ipv4. */
899 	if (hints->ai_family == PF_INET || hints->ai_family == PF_UNSPEC) {
900 		struct sockaddr_in sin;
901 		memset(&sin, 0, sizeof(sin));
902 		if (1==evutil_inet_pton(AF_INET, nodename, &sin.sin_addr)) {
903 			/* Got an ipv6 address. */
904 			sin.sin_family = AF_INET;
905 			sin.sin_port = htons(port);
906 			*res = evutil_new_addrinfo((struct sockaddr*)&sin,
907 			    sizeof(sin), hints);
908 			if (!*res)
909 				return EVUTIL_EAI_MEMORY;
910 			return 0;
911 		}
912 	}
913 
914 
915 	/* If we have reached this point, we definitely need to do a DNS
916 	 * lookup. */
917 	if ((hints->ai_flags & EVUTIL_AI_NUMERICHOST)) {
918 		/* If we're not allowed to do one, then say so. */
919 		return EVUTIL_EAI_NONAME;
920 	}
921 	*portnum = port;
922 	return EVUTIL_EAI_NEED_RESOLVE;
923 }
924 
925 #ifdef _EVENT_HAVE_GETADDRINFO
926 #define USE_NATIVE_GETADDRINFO
927 #endif
928 
929 #ifdef USE_NATIVE_GETADDRINFO
930 /* A mask of all the flags that we declare, so we can clear them before calling
931  * the native getaddrinfo */
932 static const unsigned int ALL_NONNATIVE_AI_FLAGS =
933 #ifndef AI_PASSIVE
934     EVUTIL_AI_PASSIVE |
935 #endif
936 #ifndef AI_CANONNAME
937     EVUTIL_AI_CANONNAME |
938 #endif
939 #ifndef AI_NUMERICHOST
940     EVUTIL_AI_NUMERICHOST |
941 #endif
942 #ifndef AI_NUMERICSERV
943     EVUTIL_AI_NUMERICSERV |
944 #endif
945 #ifndef AI_ADDRCONFIG
946     EVUTIL_AI_ADDRCONFIG |
947 #endif
948 #ifndef AI_ALL
949     EVUTIL_AI_ALL |
950 #endif
951 #ifndef AI_V4MAPPED
952     EVUTIL_AI_V4MAPPED |
953 #endif
954     EVUTIL_AI_LIBEVENT_ALLOCATED;
955 
956 static const unsigned int ALL_NATIVE_AI_FLAGS =
957 #ifdef AI_PASSIVE
958     AI_PASSIVE |
959 #endif
960 #ifdef AI_CANONNAME
961     AI_CANONNAME |
962 #endif
963 #ifdef AI_NUMERICHOST
964     AI_NUMERICHOST |
965 #endif
966 #ifdef AI_NUMERICSERV
967     AI_NUMERICSERV |
968 #endif
969 #ifdef AI_ADDRCONFIG
970     AI_ADDRCONFIG |
971 #endif
972 #ifdef AI_ALL
973     AI_ALL |
974 #endif
975 #ifdef AI_V4MAPPED
976     AI_V4MAPPED |
977 #endif
978     0;
979 #endif
980 
981 #ifndef USE_NATIVE_GETADDRINFO
982 /* Helper for systems with no getaddrinfo(): make one or more addrinfos out of
983  * a struct hostent.
984  */
985 static struct evutil_addrinfo *
addrinfo_from_hostent(const struct hostent * ent,int port,const struct evutil_addrinfo * hints)986 addrinfo_from_hostent(const struct hostent *ent,
987     int port, const struct evutil_addrinfo *hints)
988 {
989 	int i;
990 	struct sockaddr_in sin;
991 	struct sockaddr_in6 sin6;
992 	struct sockaddr *sa;
993 	int socklen;
994 	struct evutil_addrinfo *res=NULL, *ai;
995 	void *addrp;
996 
997 	if (ent->h_addrtype == PF_INET) {
998 		memset(&sin, 0, sizeof(sin));
999 		sin.sin_family = AF_INET;
1000 		sin.sin_port = htons(port);
1001 		sa = (struct sockaddr *)&sin;
1002 		socklen = sizeof(struct sockaddr_in);
1003 		addrp = &sin.sin_addr;
1004 		if (ent->h_length != sizeof(sin.sin_addr)) {
1005 			event_warnx("Weird h_length from gethostbyname");
1006 			return NULL;
1007 		}
1008 	} else if (ent->h_addrtype == PF_INET6) {
1009 		memset(&sin6, 0, sizeof(sin6));
1010 		sin6.sin6_family = AF_INET6;
1011 		sin6.sin6_port = htons(port);
1012 		sa = (struct sockaddr *)&sin6;
1013 		socklen = sizeof(struct sockaddr_in);
1014 		addrp = &sin6.sin6_addr;
1015 		if (ent->h_length != sizeof(sin6.sin6_addr)) {
1016 			event_warnx("Weird h_length from gethostbyname");
1017 			return NULL;
1018 		}
1019 	} else
1020 		return NULL;
1021 
1022 	for (i = 0; ent->h_addr_list[i]; ++i) {
1023 		memcpy(addrp, ent->h_addr_list[i], ent->h_length);
1024 		ai = evutil_new_addrinfo(sa, socklen, hints);
1025 		if (!ai) {
1026 			evutil_freeaddrinfo(res);
1027 			return NULL;
1028 		}
1029 		res = evutil_addrinfo_append(res, ai);
1030 	}
1031 
1032 	if (res && ((hints->ai_flags & EVUTIL_AI_CANONNAME) && ent->h_name)) {
1033 		res->ai_canonname = mm_strdup(ent->h_name);
1034 		if (res->ai_canonname == NULL) {
1035 			evutil_freeaddrinfo(res);
1036 			return NULL;
1037 		}
1038 	}
1039 
1040 	return res;
1041 }
1042 #endif
1043 
1044 /* If the EVUTIL_AI_ADDRCONFIG flag is set on hints->ai_flags, and
1045  * hints->ai_family is PF_UNSPEC, then revise the value of hints->ai_family so
1046  * that we'll only get addresses we could maybe connect to.
1047  */
1048 void
evutil_adjust_hints_for_addrconfig(struct evutil_addrinfo * hints)1049 evutil_adjust_hints_for_addrconfig(struct evutil_addrinfo *hints)
1050 {
1051 	if (!(hints->ai_flags & EVUTIL_AI_ADDRCONFIG))
1052 		return;
1053 	if (hints->ai_family != PF_UNSPEC)
1054 		return;
1055 	if (!have_checked_interfaces)
1056 		evutil_check_interfaces(0);
1057 	if (had_ipv4_address && !had_ipv6_address) {
1058 		hints->ai_family = PF_INET;
1059 	} else if (!had_ipv4_address && had_ipv6_address) {
1060 		hints->ai_family = PF_INET6;
1061 	}
1062 }
1063 
1064 #ifdef USE_NATIVE_GETADDRINFO
1065 static int need_numeric_port_hack_=0;
1066 static int need_socktype_protocol_hack_=0;
1067 static int tested_for_getaddrinfo_hacks=0;
1068 
1069 /* Some older BSDs (like OpenBSD up to 4.6) used to believe that
1070    giving a numeric port without giving an ai_socktype was verboten.
1071    We test for this so we can apply an appropriate workaround.  If it
1072    turns out that the bug is present, then:
1073 
1074     - If nodename==NULL and servname is numeric, we build an answer
1075       ourselves using evutil_getaddrinfo_common().
1076 
1077     - If nodename!=NULL and servname is numeric, then we set
1078       servname=NULL when calling getaddrinfo, and post-process the
1079       result to set the ports on it.
1080 
1081    We test for this bug at runtime, since otherwise we can't have the
1082    same binary run on multiple BSD versions.
1083 
1084    - Some versions of Solaris believe that it's nice to leave to protocol
1085      field set to 0.  We test for this so we can apply an appropriate
1086      workaround.
1087 */
1088 static void
test_for_getaddrinfo_hacks(void)1089 test_for_getaddrinfo_hacks(void)
1090 {
1091 	int r, r2;
1092 	struct evutil_addrinfo *ai=NULL, *ai2=NULL;
1093 	struct evutil_addrinfo hints;
1094 
1095 	memset(&hints,0,sizeof(hints));
1096 	hints.ai_family = PF_UNSPEC;
1097 	hints.ai_flags =
1098 #ifdef AI_NUMERICHOST
1099 	    AI_NUMERICHOST |
1100 #endif
1101 #ifdef AI_NUMERICSERV
1102 	    AI_NUMERICSERV |
1103 #endif
1104 	    0;
1105 	r = getaddrinfo("1.2.3.4", "80", &hints, &ai);
1106 	hints.ai_socktype = SOCK_STREAM;
1107 	r2 = getaddrinfo("1.2.3.4", "80", &hints, &ai2);
1108 	if (r2 == 0 && r != 0) {
1109 		need_numeric_port_hack_=1;
1110 	}
1111 	if (ai2 && ai2->ai_protocol == 0) {
1112 		need_socktype_protocol_hack_=1;
1113 	}
1114 
1115 	if (ai)
1116 		freeaddrinfo(ai);
1117 	if (ai2)
1118 		freeaddrinfo(ai2);
1119 	tested_for_getaddrinfo_hacks=1;
1120 }
1121 
1122 static inline int
need_numeric_port_hack(void)1123 need_numeric_port_hack(void)
1124 {
1125 	if (!tested_for_getaddrinfo_hacks)
1126 		test_for_getaddrinfo_hacks();
1127 	return need_numeric_port_hack_;
1128 }
1129 
1130 static inline int
need_socktype_protocol_hack(void)1131 need_socktype_protocol_hack(void)
1132 {
1133 	if (!tested_for_getaddrinfo_hacks)
1134 		test_for_getaddrinfo_hacks();
1135 	return need_socktype_protocol_hack_;
1136 }
1137 
1138 static void
apply_numeric_port_hack(int port,struct evutil_addrinfo ** ai)1139 apply_numeric_port_hack(int port, struct evutil_addrinfo **ai)
1140 {
1141 	/* Now we run through the list and set the ports on all of the
1142 	 * results where ports would make sense. */
1143 	for ( ; *ai; ai = &(*ai)->ai_next) {
1144 		struct sockaddr *sa = (*ai)->ai_addr;
1145 		if (sa && sa->sa_family == AF_INET) {
1146 			struct sockaddr_in *sin = (struct sockaddr_in*)sa;
1147 			sin->sin_port = htons(port);
1148 		} else if (sa && sa->sa_family == AF_INET6) {
1149 			struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)sa;
1150 			sin6->sin6_port = htons(port);
1151 		} else {
1152 			/* A numeric port makes no sense here; remove this one
1153 			 * from the list. */
1154 			struct evutil_addrinfo *victim = *ai;
1155 			*ai = victim->ai_next;
1156 			victim->ai_next = NULL;
1157 			freeaddrinfo(victim);
1158 		}
1159 	}
1160 }
1161 
1162 static int
apply_socktype_protocol_hack(struct evutil_addrinfo * ai)1163 apply_socktype_protocol_hack(struct evutil_addrinfo *ai)
1164 {
1165 	struct evutil_addrinfo *ai_new;
1166 	for (; ai; ai = ai->ai_next) {
1167 		evutil_getaddrinfo_infer_protocols(ai);
1168 		if (ai->ai_socktype || ai->ai_protocol)
1169 			continue;
1170 		ai_new = mm_malloc(sizeof(*ai_new));
1171 		if (!ai_new)
1172 			return -1;
1173 		memcpy(ai_new, ai, sizeof(*ai_new));
1174 		ai->ai_socktype = SOCK_STREAM;
1175 		ai->ai_protocol = IPPROTO_TCP;
1176 		ai_new->ai_socktype = SOCK_DGRAM;
1177 		ai_new->ai_protocol = IPPROTO_UDP;
1178 
1179 		ai_new->ai_next = ai->ai_next;
1180 		ai->ai_next = ai_new;
1181 	}
1182 	return 0;
1183 }
1184 #endif
1185 
1186 int
evutil_getaddrinfo(const char * nodename,const char * servname,const struct evutil_addrinfo * hints_in,struct evutil_addrinfo ** res)1187 evutil_getaddrinfo(const char *nodename, const char *servname,
1188     const struct evutil_addrinfo *hints_in, struct evutil_addrinfo **res)
1189 {
1190 #ifdef USE_NATIVE_GETADDRINFO
1191 	struct evutil_addrinfo hints;
1192 	int portnum=-1, need_np_hack, err;
1193 
1194 	if (hints_in) {
1195 		memcpy(&hints, hints_in, sizeof(hints));
1196 	} else {
1197 		memset(&hints, 0, sizeof(hints));
1198 		hints.ai_family = PF_UNSPEC;
1199 	}
1200 
1201 #ifndef AI_ADDRCONFIG
1202 	/* Not every system has AI_ADDRCONFIG, so fake it. */
1203 	if (hints.ai_family == PF_UNSPEC &&
1204 	    (hints.ai_flags & EVUTIL_AI_ADDRCONFIG)) {
1205 		evutil_adjust_hints_for_addrconfig(&hints);
1206 	}
1207 #endif
1208 
1209 #ifndef AI_NUMERICSERV
1210 	/* Not every system has AI_NUMERICSERV, so fake it. */
1211 	if (hints.ai_flags & EVUTIL_AI_NUMERICSERV) {
1212 		if (servname && parse_numeric_servname(servname)<0)
1213 			return EVUTIL_EAI_NONAME;
1214 	}
1215 #endif
1216 
1217 	/* Enough operating systems handle enough common non-resolve
1218 	 * cases here weirdly enough that we are better off just
1219 	 * overriding them.  For example:
1220 	 *
1221 	 * - Windows doesn't like to infer the protocol from the
1222 	 *   socket type, or fill in socket or protocol types much at
1223 	 *   all.  It also seems to do its own broken implicit
1224 	 *   always-on version of AI_ADDRCONFIG that keeps it from
1225 	 *   ever resolving even a literal IPv6 address when
1226 	 *   ai_addrtype is PF_UNSPEC.
1227 	 */
1228 #ifdef WIN32
1229 	{
1230 		int tmp_port;
1231 		err = evutil_getaddrinfo_common(nodename,servname,&hints,
1232 		    res, &tmp_port);
1233 		if (err == 0 ||
1234 		    err == EVUTIL_EAI_MEMORY ||
1235 		    err == EVUTIL_EAI_NONAME)
1236 			return err;
1237 		/* If we make it here, the system getaddrinfo can
1238 		 * have a crack at it. */
1239 	}
1240 #endif
1241 
1242 	/* See documentation for need_numeric_port_hack above.*/
1243 	need_np_hack = need_numeric_port_hack() && servname && !hints.ai_socktype
1244 	    && ((portnum=parse_numeric_servname(servname)) >= 0);
1245 	if (need_np_hack) {
1246 		if (!nodename)
1247 			return evutil_getaddrinfo_common(
1248 				NULL,servname,&hints, res, &portnum);
1249 		servname = NULL;
1250 	}
1251 
1252 	if (need_socktype_protocol_hack()) {
1253 		evutil_getaddrinfo_infer_protocols(&hints);
1254 	}
1255 
1256 	/* Make sure that we didn't actually steal any AI_FLAGS values that
1257 	 * the system is using.  (This is a constant expression, and should ge
1258 	 * optimized out.)
1259 	 *
1260 	 * XXXX Turn this into a compile-time failure rather than a run-time
1261 	 * failure.
1262 	 */
1263 	EVUTIL_ASSERT((ALL_NONNATIVE_AI_FLAGS & ALL_NATIVE_AI_FLAGS) == 0);
1264 
1265 	/* Clear any flags that only libevent understands. */
1266 	hints.ai_flags &= ~ALL_NONNATIVE_AI_FLAGS;
1267 
1268 	err = getaddrinfo(nodename, servname, &hints, res);
1269 	if (need_np_hack)
1270 		apply_numeric_port_hack(portnum, res);
1271 
1272 	if (need_socktype_protocol_hack()) {
1273 		if (apply_socktype_protocol_hack(*res) < 0) {
1274 			evutil_freeaddrinfo(*res);
1275 			*res = NULL;
1276 			return EVUTIL_EAI_MEMORY;
1277 		}
1278 	}
1279 	return err;
1280 #else
1281 	int port=0, err;
1282 	struct hostent *ent = NULL;
1283 	struct evutil_addrinfo hints;
1284 
1285 	if (hints_in) {
1286 		memcpy(&hints, hints_in, sizeof(hints));
1287 	} else {
1288 		memset(&hints, 0, sizeof(hints));
1289 		hints.ai_family = PF_UNSPEC;
1290 	}
1291 
1292 	evutil_adjust_hints_for_addrconfig(&hints);
1293 
1294 	err = evutil_getaddrinfo_common(nodename, servname, &hints, res, &port);
1295 	if (err != EVUTIL_EAI_NEED_RESOLVE) {
1296 		/* We either succeeded or failed.  No need to continue */
1297 		return err;
1298 	}
1299 
1300 	err = 0;
1301 	/* Use any of the various gethostbyname_r variants as available. */
1302 	{
1303 #ifdef _EVENT_HAVE_GETHOSTBYNAME_R_6_ARG
1304 		/* This one is what glibc provides. */
1305 		char buf[2048];
1306 		struct hostent hostent;
1307 		int r;
1308 		r = gethostbyname_r(nodename, &hostent, buf, sizeof(buf), &ent,
1309 		    &err);
1310 #elif defined(_EVENT_HAVE_GETHOSTBYNAME_R_5_ARG)
1311 		char buf[2048];
1312 		struct hostent hostent;
1313 		ent = gethostbyname_r(nodename, &hostent, buf, sizeof(buf),
1314 		    &err);
1315 #elif defined(_EVENT_HAVE_GETHOSTBYNAME_R_3_ARG)
1316 		struct hostent_data data;
1317 		struct hostent hostent;
1318 		memset(&data, 0, sizeof(data));
1319 		err = gethostbyname_r(nodename, &hostent, &data);
1320 		ent = err ? NULL : &hostent;
1321 #else
1322 		/* fall back to gethostbyname. */
1323 		/* XXXX This needs a lock everywhere but Windows. */
1324 		ent = gethostbyname(nodename);
1325 #ifdef WIN32
1326 		err = WSAGetLastError();
1327 #else
1328 		err = h_errno;
1329 #endif
1330 #endif
1331 
1332 		/* Now we have either ent or err set. */
1333 		if (!ent) {
1334 			/* XXX is this right for windows ? */
1335 			switch (err) {
1336 			case TRY_AGAIN:
1337 				return EVUTIL_EAI_AGAIN;
1338 			case NO_RECOVERY:
1339 			default:
1340 				return EVUTIL_EAI_FAIL;
1341 			case HOST_NOT_FOUND:
1342 				return EVUTIL_EAI_NONAME;
1343 			case NO_ADDRESS:
1344 #if NO_DATA != NO_ADDRESS
1345 			case NO_DATA:
1346 #endif
1347 				return EVUTIL_EAI_NODATA;
1348 			}
1349 		}
1350 
1351 		if (ent->h_addrtype != hints.ai_family &&
1352 		    hints.ai_family != PF_UNSPEC) {
1353 			/* This wasn't the type we were hoping for.  Too bad
1354 			 * we never had a chance to ask gethostbyname for what
1355 			 * we wanted. */
1356 			return EVUTIL_EAI_NONAME;
1357 		}
1358 
1359 		/* Make sure we got _some_ answers. */
1360 		if (ent->h_length == 0)
1361 			return EVUTIL_EAI_NODATA;
1362 
1363 		/* If we got an address type we don't know how to make a
1364 		   sockaddr for, give up. */
1365 		if (ent->h_addrtype != PF_INET && ent->h_addrtype != PF_INET6)
1366 			return EVUTIL_EAI_FAMILY;
1367 
1368 		*res = addrinfo_from_hostent(ent, port, &hints);
1369 		if (! *res)
1370 			return EVUTIL_EAI_MEMORY;
1371 	}
1372 
1373 	return 0;
1374 #endif
1375 }
1376 
1377 void
evutil_freeaddrinfo(struct evutil_addrinfo * ai)1378 evutil_freeaddrinfo(struct evutil_addrinfo *ai)
1379 {
1380 #ifdef _EVENT_HAVE_GETADDRINFO
1381 	if (!(ai->ai_flags & EVUTIL_AI_LIBEVENT_ALLOCATED)) {
1382 		freeaddrinfo(ai);
1383 		return;
1384 	}
1385 #endif
1386 	while (ai) {
1387 		struct evutil_addrinfo *next = ai->ai_next;
1388 		if (ai->ai_canonname)
1389 			mm_free(ai->ai_canonname);
1390 		mm_free(ai);
1391 		ai = next;
1392 	}
1393 }
1394 
1395 static evdns_getaddrinfo_fn evdns_getaddrinfo_impl = NULL;
1396 
1397 void
evutil_set_evdns_getaddrinfo_fn(evdns_getaddrinfo_fn fn)1398 evutil_set_evdns_getaddrinfo_fn(evdns_getaddrinfo_fn fn)
1399 {
1400 	if (!evdns_getaddrinfo_impl)
1401 		evdns_getaddrinfo_impl = fn;
1402 }
1403 
1404 /* Internal helper function: act like evdns_getaddrinfo if dns_base is set;
1405  * otherwise do a blocking resolve and pass the result to the callback in the
1406  * way that evdns_getaddrinfo would.
1407  */
1408 int
evutil_getaddrinfo_async(struct evdns_base * dns_base,const char * nodename,const char * servname,const struct evutil_addrinfo * hints_in,void (* cb)(int,struct evutil_addrinfo *,void *),void * arg)1409 evutil_getaddrinfo_async(struct evdns_base *dns_base,
1410     const char *nodename, const char *servname,
1411     const struct evutil_addrinfo *hints_in,
1412     void (*cb)(int, struct evutil_addrinfo *, void *), void *arg)
1413 {
1414 	if (dns_base && evdns_getaddrinfo_impl) {
1415 		evdns_getaddrinfo_impl(
1416 			dns_base, nodename, servname, hints_in, cb, arg);
1417 	} else {
1418 		struct evutil_addrinfo *ai=NULL;
1419 		int err;
1420 		err = evutil_getaddrinfo(nodename, servname, hints_in, &ai);
1421 		cb(err, ai, arg);
1422 	}
1423 	return 0;
1424 }
1425 
1426 const char *
evutil_gai_strerror(int err)1427 evutil_gai_strerror(int err)
1428 {
1429 	/* As a sneaky side-benefit, this case statement will get most
1430 	 * compilers to tell us if any of the error codes we defined
1431 	 * conflict with the platform's native error codes. */
1432 	switch (err) {
1433 	case EVUTIL_EAI_CANCEL:
1434 		return "Request canceled";
1435 	case 0:
1436 		return "No error";
1437 
1438 	case EVUTIL_EAI_ADDRFAMILY:
1439 		return "address family for nodename not supported";
1440 	case EVUTIL_EAI_AGAIN:
1441 		return "temporary failure in name resolution";
1442 	case EVUTIL_EAI_BADFLAGS:
1443 		return "invalid value for ai_flags";
1444 	case EVUTIL_EAI_FAIL:
1445 		return "non-recoverable failure in name resolution";
1446 	case EVUTIL_EAI_FAMILY:
1447 		return "ai_family not supported";
1448 	case EVUTIL_EAI_MEMORY:
1449 		return "memory allocation failure";
1450 	case EVUTIL_EAI_NODATA:
1451 		return "no address associated with nodename";
1452 	case EVUTIL_EAI_NONAME:
1453 		return "nodename nor servname provided, or not known";
1454 	case EVUTIL_EAI_SERVICE:
1455 		return "servname not supported for ai_socktype";
1456 	case EVUTIL_EAI_SOCKTYPE:
1457 		return "ai_socktype not supported";
1458 	case EVUTIL_EAI_SYSTEM:
1459 		return "system error";
1460 	default:
1461 #if defined(USE_NATIVE_GETADDRINFO) && defined(WIN32)
1462 		return gai_strerrorA(err);
1463 #elif defined(USE_NATIVE_GETADDRINFO)
1464 		return gai_strerror(err);
1465 #else
1466 		return "Unknown error code";
1467 #endif
1468 	}
1469 }
1470 
1471 #ifdef WIN32
1472 #define E(code, s) { code, (s " [" #code " ]") }
1473 static struct { int code; const char *msg; } windows_socket_errors[] = {
1474   E(WSAEINTR, "Interrupted function call"),
1475   E(WSAEACCES, "Permission denied"),
1476   E(WSAEFAULT, "Bad address"),
1477   E(WSAEINVAL, "Invalid argument"),
1478   E(WSAEMFILE, "Too many open files"),
1479   E(WSAEWOULDBLOCK,  "Resource temporarily unavailable"),
1480   E(WSAEINPROGRESS, "Operation now in progress"),
1481   E(WSAEALREADY, "Operation already in progress"),
1482   E(WSAENOTSOCK, "Socket operation on nonsocket"),
1483   E(WSAEDESTADDRREQ, "Destination address required"),
1484   E(WSAEMSGSIZE, "Message too long"),
1485   E(WSAEPROTOTYPE, "Protocol wrong for socket"),
1486   E(WSAENOPROTOOPT, "Bad protocol option"),
1487   E(WSAEPROTONOSUPPORT, "Protocol not supported"),
1488   E(WSAESOCKTNOSUPPORT, "Socket type not supported"),
1489   /* What's the difference between NOTSUPP and NOSUPPORT? :) */
1490   E(WSAEOPNOTSUPP, "Operation not supported"),
1491   E(WSAEPFNOSUPPORT,  "Protocol family not supported"),
1492   E(WSAEAFNOSUPPORT, "Address family not supported by protocol family"),
1493   E(WSAEADDRINUSE, "Address already in use"),
1494   E(WSAEADDRNOTAVAIL, "Cannot assign requested address"),
1495   E(WSAENETDOWN, "Network is down"),
1496   E(WSAENETUNREACH, "Network is unreachable"),
1497   E(WSAENETRESET, "Network dropped connection on reset"),
1498   E(WSAECONNABORTED, "Software caused connection abort"),
1499   E(WSAECONNRESET, "Connection reset by peer"),
1500   E(WSAENOBUFS, "No buffer space available"),
1501   E(WSAEISCONN, "Socket is already connected"),
1502   E(WSAENOTCONN, "Socket is not connected"),
1503   E(WSAESHUTDOWN, "Cannot send after socket shutdown"),
1504   E(WSAETIMEDOUT, "Connection timed out"),
1505   E(WSAECONNREFUSED, "Connection refused"),
1506   E(WSAEHOSTDOWN, "Host is down"),
1507   E(WSAEHOSTUNREACH, "No route to host"),
1508   E(WSAEPROCLIM, "Too many processes"),
1509 
1510   /* Yes, some of these start with WSA, not WSAE. No, I don't know why. */
1511   E(WSASYSNOTREADY, "Network subsystem is unavailable"),
1512   E(WSAVERNOTSUPPORTED, "Winsock.dll out of range"),
1513   E(WSANOTINITIALISED, "Successful WSAStartup not yet performed"),
1514   E(WSAEDISCON, "Graceful shutdown now in progress"),
1515 #ifdef WSATYPE_NOT_FOUND
1516   E(WSATYPE_NOT_FOUND, "Class type not found"),
1517 #endif
1518   E(WSAHOST_NOT_FOUND, "Host not found"),
1519   E(WSATRY_AGAIN, "Nonauthoritative host not found"),
1520   E(WSANO_RECOVERY, "This is a nonrecoverable error"),
1521   E(WSANO_DATA, "Valid name, no data record of requested type)"),
1522 
1523   /* There are some more error codes whose numeric values are marked
1524    * <b>OS dependent</b>. They start with WSA_, apparently for the same
1525    * reason that practitioners of some craft traditions deliberately
1526    * introduce imperfections into their baskets and rugs "to allow the
1527    * evil spirits to escape."  If we catch them, then our binaries
1528    * might not report consistent results across versions of Windows.
1529    * Thus, I'm going to let them all fall through.
1530    */
1531   { -1, NULL },
1532 };
1533 #undef E
1534 /** Equivalent to strerror, but for windows socket errors. */
1535 const char *
evutil_socket_error_to_string(int errcode)1536 evutil_socket_error_to_string(int errcode)
1537 {
1538   /* XXXX Is there really no built-in function to do this? */
1539   int i;
1540   for (i=0; windows_socket_errors[i].code >= 0; ++i) {
1541     if (errcode == windows_socket_errors[i].code)
1542       return windows_socket_errors[i].msg;
1543   }
1544   return strerror(errcode);
1545 }
1546 #endif
1547 
1548 int
evutil_snprintf(char * buf,size_t buflen,const char * format,...)1549 evutil_snprintf(char *buf, size_t buflen, const char *format, ...)
1550 {
1551 	int r;
1552 	va_list ap;
1553 	va_start(ap, format);
1554 	r = evutil_vsnprintf(buf, buflen, format, ap);
1555 	va_end(ap);
1556 	return r;
1557 }
1558 
1559 int
evutil_vsnprintf(char * buf,size_t buflen,const char * format,va_list ap)1560 evutil_vsnprintf(char *buf, size_t buflen, const char *format, va_list ap)
1561 {
1562 	int r;
1563 	if (!buflen)
1564 		return 0;
1565 #if defined(_MSC_VER) || defined(WIN32)
1566 	r = _vsnprintf(buf, buflen, format, ap);
1567 	if (r < 0)
1568 		r = _vscprintf(format, ap);
1569 #elif defined(sgi)
1570 	/* Make sure we always use the correct vsnprintf on IRIX */
1571 	extern int      _xpg5_vsnprintf(char * __restrict,
1572 		__SGI_LIBC_NAMESPACE_QUALIFIER size_t,
1573 		const char * __restrict, /* va_list */ char *);
1574 
1575 	r = _xpg5_vsnprintf(buf, buflen, format, ap);
1576 #else
1577 	r = vsnprintf(buf, buflen, format, ap);
1578 #endif
1579 	buf[buflen-1] = '\0';
1580 	return r;
1581 }
1582 
1583 #define USE_INTERNAL_NTOP
1584 #define USE_INTERNAL_PTON
1585 
1586 const char *
evutil_inet_ntop(int af,const void * src,char * dst,size_t len)1587 evutil_inet_ntop(int af, const void *src, char *dst, size_t len)
1588 {
1589 #if defined(_EVENT_HAVE_INET_NTOP) && !defined(USE_INTERNAL_NTOP)
1590 	return inet_ntop(af, src, dst, len);
1591 #else
1592 	if (af == AF_INET) {
1593 		const struct in_addr *in = src;
1594 		const ev_uint32_t a = ntohl(in->s_addr);
1595 		int r;
1596 		r = evutil_snprintf(dst, len, "%d.%d.%d.%d",
1597 		    (int)(ev_uint8_t)((a>>24)&0xff),
1598 		    (int)(ev_uint8_t)((a>>16)&0xff),
1599 		    (int)(ev_uint8_t)((a>>8 )&0xff),
1600 		    (int)(ev_uint8_t)((a    )&0xff));
1601 		if (r<0||(size_t)r>=len)
1602 			return NULL;
1603 		else
1604 			return dst;
1605 #ifdef AF_INET6
1606 	} else if (af == AF_INET6) {
1607 		const struct in6_addr *addr = src;
1608 		char buf[64], *cp;
1609 		int longestGapLen = 0, longestGapPos = -1, i,
1610 			curGapPos = -1, curGapLen = 0;
1611 		ev_uint16_t words[8];
1612 		for (i = 0; i < 8; ++i) {
1613 			words[i] =
1614 			    (((ev_uint16_t)addr->s6_addr[2*i])<<8) + addr->s6_addr[2*i+1];
1615 		}
1616 		if (words[0] == 0 && words[1] == 0 && words[2] == 0 && words[3] == 0 &&
1617 		    words[4] == 0 && ((words[5] == 0 && words[6] && words[7]) ||
1618 			(words[5] == 0xffff))) {
1619 			/* This is an IPv4 address. */
1620 			if (words[5] == 0) {
1621 				evutil_snprintf(buf, sizeof(buf), "::%d.%d.%d.%d",
1622 				    addr->s6_addr[12], addr->s6_addr[13],
1623 				    addr->s6_addr[14], addr->s6_addr[15]);
1624 			} else {
1625 				evutil_snprintf(buf, sizeof(buf), "::%x:%d.%d.%d.%d", words[5],
1626 				    addr->s6_addr[12], addr->s6_addr[13],
1627 				    addr->s6_addr[14], addr->s6_addr[15]);
1628 			}
1629 			if (strlen(buf) > len)
1630 				return NULL;
1631 			strlcpy(dst, buf, len);
1632 			return dst;
1633 		}
1634 		i = 0;
1635 		while (i < 8) {
1636 			if (words[i] == 0) {
1637 				curGapPos = i++;
1638 				curGapLen = 1;
1639 				while (i<8 && words[i] == 0) {
1640 					++i; ++curGapLen;
1641 				}
1642 				if (curGapLen > longestGapLen) {
1643 					longestGapPos = curGapPos;
1644 					longestGapLen = curGapLen;
1645 				}
1646 			} else {
1647 				++i;
1648 			}
1649 		}
1650 		if (longestGapLen<=1)
1651 			longestGapPos = -1;
1652 
1653 		cp = buf;
1654 		for (i = 0; i < 8; ++i) {
1655 			if (words[i] == 0 && longestGapPos == i) {
1656 				if (i == 0)
1657 					*cp++ = ':';
1658 				*cp++ = ':';
1659 				while (i < 8 && words[i] == 0)
1660 					++i;
1661 				--i; /* to compensate for loop increment. */
1662 			} else {
1663 				evutil_snprintf(cp,
1664 								sizeof(buf)-(cp-buf), "%x", (unsigned)words[i]);
1665 				cp += strlen(cp);
1666 				if (i != 7)
1667 					*cp++ = ':';
1668 			}
1669 		}
1670 		*cp = '\0';
1671 		if (strlen(buf) > len)
1672 			return NULL;
1673 		strlcpy(dst, buf, len);
1674 		return dst;
1675 #endif
1676 	} else {
1677 		return NULL;
1678 	}
1679 #endif
1680 }
1681 
1682 int
evutil_inet_pton(int af,const char * src,void * dst)1683 evutil_inet_pton(int af, const char *src, void *dst)
1684 {
1685 #if defined(_EVENT_HAVE_INET_PTON) && !defined(USE_INTERNAL_PTON)
1686 	return inet_pton(af, src, dst);
1687 #else
1688 	if (af == AF_INET) {
1689 		int a,b,c,d;
1690 		char more;
1691 		struct in_addr *addr = dst;
1692 		if (sscanf(src, "%d.%d.%d.%d%c", &a,&b,&c,&d,&more) != 4)
1693 			return 0;
1694 		if (a < 0 || a > 255) return 0;
1695 		if (b < 0 || b > 255) return 0;
1696 		if (c < 0 || c > 255) return 0;
1697 		if (d < 0 || d > 255) return 0;
1698 		addr->s_addr = htonl((a<<24) | (b<<16) | (c<<8) | d);
1699 		return 1;
1700 #ifdef AF_INET6
1701 	} else if (af == AF_INET6) {
1702 		struct in6_addr *out = dst;
1703 		ev_uint16_t words[8];
1704 		int gapPos = -1, i, setWords=0;
1705 		const char *dot = strchr(src, '.');
1706 		const char *eow; /* end of words. */
1707 		if (dot == src)
1708 			return 0;
1709 		else if (!dot)
1710 			eow = src+strlen(src);
1711 		else {
1712 			int byte1,byte2,byte3,byte4;
1713 			char more;
1714 			for (eow = dot-1; eow >= src && EVUTIL_ISDIGIT(*eow); --eow)
1715 				;
1716 			++eow;
1717 
1718 			/* We use "scanf" because some platform inet_aton()s are too lax
1719 			 * about IPv4 addresses of the form "1.2.3" */
1720 			if (sscanf(eow, "%d.%d.%d.%d%c",
1721 					   &byte1,&byte2,&byte3,&byte4,&more) != 4)
1722 				return 0;
1723 
1724 			if (byte1 > 255 || byte1 < 0 ||
1725 				byte2 > 255 || byte2 < 0 ||
1726 				byte3 > 255 || byte3 < 0 ||
1727 				byte4 > 255 || byte4 < 0)
1728 				return 0;
1729 
1730 			words[6] = (byte1<<8) | byte2;
1731 			words[7] = (byte3<<8) | byte4;
1732 			setWords += 2;
1733 		}
1734 
1735 		i = 0;
1736 		while (src < eow) {
1737 			if (i > 7)
1738 				return 0;
1739 			if (EVUTIL_ISXDIGIT(*src)) {
1740 				char *next;
1741 				long r = strtol(src, &next, 16);
1742 				if (next > 4+src)
1743 					return 0;
1744 				if (next == src)
1745 					return 0;
1746 				if (r<0 || r>65536)
1747 					return 0;
1748 
1749 				words[i++] = (ev_uint16_t)r;
1750 				setWords++;
1751 				src = next;
1752 				if (*src != ':' && src != eow)
1753 					return 0;
1754 				++src;
1755 			} else if (*src == ':' && i > 0 && gapPos==-1) {
1756 				gapPos = i;
1757 				++src;
1758 			} else if (*src == ':' && i == 0 && src[1] == ':' && gapPos==-1) {
1759 				gapPos = i;
1760 				src += 2;
1761 			} else {
1762 				return 0;
1763 			}
1764 		}
1765 
1766 		if (setWords > 8 ||
1767 			(setWords == 8 && gapPos != -1) ||
1768 			(setWords < 8 && gapPos == -1))
1769 			return 0;
1770 
1771 		if (gapPos >= 0) {
1772 			int nToMove = setWords - (dot ? 2 : 0) - gapPos;
1773 			int gapLen = 8 - setWords;
1774 			/* assert(nToMove >= 0); */
1775 			if (nToMove < 0)
1776 				return -1; /* should be impossible */
1777 			memmove(&words[gapPos+gapLen], &words[gapPos],
1778 					sizeof(ev_uint16_t)*nToMove);
1779 			memset(&words[gapPos], 0, sizeof(ev_uint16_t)*gapLen);
1780 		}
1781 		for (i = 0; i < 8; ++i) {
1782 			out->s6_addr[2*i  ] = words[i] >> 8;
1783 			out->s6_addr[2*i+1] = words[i] & 0xff;
1784 		}
1785 
1786 		return 1;
1787 #endif
1788 	} else {
1789 		return -1;
1790 	}
1791 #endif
1792 }
1793 
1794 int
evutil_parse_sockaddr_port(const char * ip_as_string,struct sockaddr * out,int * outlen)1795 evutil_parse_sockaddr_port(const char *ip_as_string, struct sockaddr *out, int *outlen)
1796 {
1797 	int port;
1798 	char buf[128];
1799 	const char *cp, *addr_part, *port_part;
1800 	int is_ipv6;
1801 	/* recognized formats are:
1802 	 * [ipv6]:port
1803 	 * ipv6
1804 	 * [ipv6]
1805 	 * ipv4:port
1806 	 * ipv4
1807 	 */
1808 
1809 	cp = strchr(ip_as_string, ':');
1810 	if (*ip_as_string == '[') {
1811 		int len;
1812 		if (!(cp = strchr(ip_as_string, ']'))) {
1813 			return -1;
1814 		}
1815 		len = (int) ( cp-(ip_as_string + 1) );
1816 		if (len > (int)sizeof(buf)-1) {
1817 			return -1;
1818 		}
1819 		memcpy(buf, ip_as_string+1, len);
1820 		buf[len] = '\0';
1821 		addr_part = buf;
1822 		if (cp[1] == ':')
1823 			port_part = cp+2;
1824 		else
1825 			port_part = NULL;
1826 		is_ipv6 = 1;
1827 	} else if (cp && strchr(cp+1, ':')) {
1828 		is_ipv6 = 1;
1829 		addr_part = ip_as_string;
1830 		port_part = NULL;
1831 	} else if (cp) {
1832 		is_ipv6 = 0;
1833 		if (cp - ip_as_string > (int)sizeof(buf)-1) {
1834 			return -1;
1835 		}
1836 		memcpy(buf, ip_as_string, cp-ip_as_string);
1837 		buf[cp-ip_as_string] = '\0';
1838 		addr_part = buf;
1839 		port_part = cp+1;
1840 	} else {
1841 		addr_part = ip_as_string;
1842 		port_part = NULL;
1843 		is_ipv6 = 0;
1844 	}
1845 
1846 	if (port_part == NULL) {
1847 		port = 0;
1848 	} else {
1849 		port = atoi(port_part);
1850 		if (port <= 0 || port > 65535) {
1851 			return -1;
1852 		}
1853 	}
1854 
1855 	if (!addr_part)
1856 		return -1; /* Should be impossible. */
1857 #ifdef AF_INET6
1858 	if (is_ipv6)
1859 	{
1860 		struct sockaddr_in6 sin6;
1861 		memset(&sin6, 0, sizeof(sin6));
1862 #ifdef _EVENT_HAVE_STRUCT_SOCKADDR_IN6_SIN6_LEN
1863 		sin6.sin6_len = sizeof(sin6);
1864 #endif
1865 		sin6.sin6_family = AF_INET6;
1866 		sin6.sin6_port = htons(port);
1867 		if (1 != evutil_inet_pton(AF_INET6, addr_part, &sin6.sin6_addr))
1868 			return -1;
1869 		if ((int)sizeof(sin6) > *outlen)
1870 			return -1;
1871 		memset(out, 0, *outlen);
1872 		memcpy(out, &sin6, sizeof(sin6));
1873 		*outlen = sizeof(sin6);
1874 		return 0;
1875 	}
1876 	else
1877 #endif
1878 	{
1879 		struct sockaddr_in sin;
1880 		memset(&sin, 0, sizeof(sin));
1881 #ifdef _EVENT_HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
1882 		sin.sin_len = sizeof(sin);
1883 #endif
1884 		sin.sin_family = AF_INET;
1885 		sin.sin_port = htons(port);
1886 		if (1 != evutil_inet_pton(AF_INET, addr_part, &sin.sin_addr))
1887 			return -1;
1888 		if ((int)sizeof(sin) > *outlen)
1889 			return -1;
1890 		memset(out, 0, *outlen);
1891 		memcpy(out, &sin, sizeof(sin));
1892 		*outlen = sizeof(sin);
1893 		return 0;
1894 	}
1895 }
1896 
1897 const char *
evutil_format_sockaddr_port(const struct sockaddr * sa,char * out,size_t outlen)1898 evutil_format_sockaddr_port(const struct sockaddr *sa, char *out, size_t outlen)
1899 {
1900 	char b[128];
1901 	const char *res=NULL;
1902 	int port;
1903 	if (sa->sa_family == AF_INET) {
1904 		const struct sockaddr_in *sin = (const struct sockaddr_in*)sa;
1905 		res = evutil_inet_ntop(AF_INET, &sin->sin_addr,b,sizeof(b));
1906 		port = ntohs(sin->sin_port);
1907 		if (res) {
1908 			evutil_snprintf(out, outlen, "%s:%d", b, port);
1909 			return out;
1910 		}
1911 	} else if (sa->sa_family == AF_INET6) {
1912 		const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6*)sa;
1913 		res = evutil_inet_ntop(AF_INET6, &sin6->sin6_addr,b,sizeof(b));
1914 		port = ntohs(sin6->sin6_port);
1915 		if (res) {
1916 			evutil_snprintf(out, outlen, "[%s]:%d", b, port);
1917 			return out;
1918 		}
1919 	}
1920 
1921 	evutil_snprintf(out, outlen, "<addr with socktype %d>",
1922 	    (int)sa->sa_family);
1923 	return out;
1924 }
1925 
1926 int
evutil_sockaddr_cmp(const struct sockaddr * sa1,const struct sockaddr * sa2,int include_port)1927 evutil_sockaddr_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2,
1928     int include_port)
1929 {
1930 	int r;
1931 	if (0 != (r = (sa1->sa_family - sa2->sa_family)))
1932 		return r;
1933 
1934 	if (sa1->sa_family == AF_INET) {
1935 		const struct sockaddr_in *sin1, *sin2;
1936 		sin1 = (const struct sockaddr_in *)sa1;
1937 		sin2 = (const struct sockaddr_in *)sa2;
1938 		if (sin1->sin_addr.s_addr < sin2->sin_addr.s_addr)
1939 			return -1;
1940 		else if (sin1->sin_addr.s_addr > sin2->sin_addr.s_addr)
1941 			return 1;
1942 		else if (include_port &&
1943 		    (r = ((int)sin1->sin_port - (int)sin2->sin_port)))
1944 			return r;
1945 		else
1946 			return 0;
1947 	}
1948 #ifdef AF_INET6
1949 	else if (sa1->sa_family == AF_INET6) {
1950 		const struct sockaddr_in6 *sin1, *sin2;
1951 		sin1 = (const struct sockaddr_in6 *)sa1;
1952 		sin2 = (const struct sockaddr_in6 *)sa2;
1953 		if ((r = memcmp(sin1->sin6_addr.s6_addr, sin2->sin6_addr.s6_addr, 16)))
1954 			return r;
1955 		else if (include_port &&
1956 		    (r = ((int)sin1->sin6_port - (int)sin2->sin6_port)))
1957 			return r;
1958 		else
1959 			return 0;
1960 	}
1961 #endif
1962 	return 1;
1963 }
1964 
1965 /* Tables to implement ctypes-replacement EVUTIL_IS*() functions.  Each table
1966  * has 256 bits to look up whether a character is in some set or not.  This
1967  * fails on non-ASCII platforms, but so does every other place where we
1968  * take a char and write it onto the network.
1969  **/
1970 static const ev_uint32_t EVUTIL_ISALPHA_TABLE[8] =
1971   { 0, 0, 0x7fffffe, 0x7fffffe, 0, 0, 0, 0 };
1972 static const ev_uint32_t EVUTIL_ISALNUM_TABLE[8] =
1973   { 0, 0x3ff0000, 0x7fffffe, 0x7fffffe, 0, 0, 0, 0 };
1974 static const ev_uint32_t EVUTIL_ISSPACE_TABLE[8] = { 0x3e00, 0x1, 0, 0, 0, 0, 0, 0 };
1975 static const ev_uint32_t EVUTIL_ISXDIGIT_TABLE[8] =
1976   { 0, 0x3ff0000, 0x7e, 0x7e, 0, 0, 0, 0 };
1977 static const ev_uint32_t EVUTIL_ISDIGIT_TABLE[8] = { 0, 0x3ff0000, 0, 0, 0, 0, 0, 0 };
1978 static const ev_uint32_t EVUTIL_ISPRINT_TABLE[8] =
1979   { 0, 0xffffffff, 0xffffffff, 0x7fffffff, 0, 0, 0, 0x0 };
1980 static const ev_uint32_t EVUTIL_ISUPPER_TABLE[8] = { 0, 0, 0x7fffffe, 0, 0, 0, 0, 0 };
1981 static const ev_uint32_t EVUTIL_ISLOWER_TABLE[8] = { 0, 0, 0, 0x7fffffe, 0, 0, 0, 0 };
1982 /* Upper-casing and lowercasing tables to map characters to upper/lowercase
1983  * equivalents. */
1984 static const unsigned char EVUTIL_TOUPPER_TABLE[256] = {
1985   0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,
1986   16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,
1987   32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,
1988   48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,
1989   64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,
1990   80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,
1991   96,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,
1992   80,81,82,83,84,85,86,87,88,89,90,123,124,125,126,127,
1993   128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
1994   144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,
1995   160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,
1996   176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,
1997   192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,
1998   208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,
1999   224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,
2000   240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255,
2001 };
2002 static const unsigned char EVUTIL_TOLOWER_TABLE[256] = {
2003   0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,
2004   16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,
2005   32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,
2006   48,49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,
2007   64,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,
2008   112,113,114,115,116,117,118,119,120,121,122,91,92,93,94,95,
2009   96,97,98,99,100,101,102,103,104,105,106,107,108,109,110,111,
2010   112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127,
2011   128,129,130,131,132,133,134,135,136,137,138,139,140,141,142,143,
2012   144,145,146,147,148,149,150,151,152,153,154,155,156,157,158,159,
2013   160,161,162,163,164,165,166,167,168,169,170,171,172,173,174,175,
2014   176,177,178,179,180,181,182,183,184,185,186,187,188,189,190,191,
2015   192,193,194,195,196,197,198,199,200,201,202,203,204,205,206,207,
2016   208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223,
2017   224,225,226,227,228,229,230,231,232,233,234,235,236,237,238,239,
2018   240,241,242,243,244,245,246,247,248,249,250,251,252,253,254,255,
2019 };
2020 
2021 #define IMPL_CTYPE_FN(name)						\
2022 	int EVUTIL_##name(char c) {					\
2023 		ev_uint8_t u = c;					\
2024 		return !!(EVUTIL_##name##_TABLE[(u >> 5) & 7] & (1 << (u & 31))); \
2025 	}
2026 IMPL_CTYPE_FN(ISALPHA)
IMPL_CTYPE_FN(ISALNUM)2027 IMPL_CTYPE_FN(ISALNUM)
2028 IMPL_CTYPE_FN(ISSPACE)
2029 IMPL_CTYPE_FN(ISDIGIT)
2030 IMPL_CTYPE_FN(ISXDIGIT)
2031 IMPL_CTYPE_FN(ISPRINT)
2032 IMPL_CTYPE_FN(ISLOWER)
2033 IMPL_CTYPE_FN(ISUPPER)
2034 
2035 char EVUTIL_TOLOWER(char c)
2036 {
2037 	return ((char)EVUTIL_TOLOWER_TABLE[(ev_uint8_t)c]);
2038 }
EVUTIL_TOUPPER(char c)2039 char EVUTIL_TOUPPER(char c)
2040 {
2041 	return ((char)EVUTIL_TOUPPER_TABLE[(ev_uint8_t)c]);
2042 }
2043 int
evutil_ascii_strcasecmp(const char * s1,const char * s2)2044 evutil_ascii_strcasecmp(const char *s1, const char *s2)
2045 {
2046 	char c1, c2;
2047 	while (1) {
2048 		c1 = EVUTIL_TOLOWER(*s1++);
2049 		c2 = EVUTIL_TOLOWER(*s2++);
2050 		if (c1 < c2)
2051 			return -1;
2052 		else if (c1 > c2)
2053 			return 1;
2054 		else if (c1 == 0)
2055 			return 0;
2056 	}
2057 }
evutil_ascii_strncasecmp(const char * s1,const char * s2,size_t n)2058 int evutil_ascii_strncasecmp(const char *s1, const char *s2, size_t n)
2059 {
2060 	char c1, c2;
2061 	while (n--) {
2062 		c1 = EVUTIL_TOLOWER(*s1++);
2063 		c2 = EVUTIL_TOLOWER(*s2++);
2064 		if (c1 < c2)
2065 			return -1;
2066 		else if (c1 > c2)
2067 			return 1;
2068 		else if (c1 == 0)
2069 			return 0;
2070 	}
2071 	return 0;
2072 }
2073 
2074 static int
evutil_issetugid(void)2075 evutil_issetugid(void)
2076 {
2077 #ifdef _EVENT_HAVE_ISSETUGID
2078 	return issetugid();
2079 #else
2080 
2081 #ifdef _EVENT_HAVE_GETEUID
2082 	if (getuid() != geteuid())
2083 		return 1;
2084 #endif
2085 #ifdef _EVENT_HAVE_GETEGID
2086 	if (getgid() != getegid())
2087 		return 1;
2088 #endif
2089 	return 0;
2090 #endif
2091 }
2092 
2093 const char *
evutil_getenv(const char * varname)2094 evutil_getenv(const char *varname)
2095 {
2096 	if (evutil_issetugid())
2097 		return NULL;
2098 
2099 	return getenv(varname);
2100 }
2101 
2102 long
_evutil_weakrand(void)2103 _evutil_weakrand(void)
2104 {
2105 #ifdef WIN32
2106 	return rand();
2107 #else
2108 	return random();
2109 #endif
2110 }
2111 
2112 /**
2113  * Volatile pointer to memset: we use this to keep the compiler from
2114  * eliminating our call to memset.
2115  */
2116 void * (*volatile evutil_memset_volatile_)(void *, int, size_t) = memset;
2117 
2118 void
evutil_memclear_(void * mem,size_t len)2119 evutil_memclear_(void *mem, size_t len)
2120 {
2121 	evutil_memset_volatile_(mem, 0, len);
2122 }
2123 
2124 int
evutil_sockaddr_is_loopback(const struct sockaddr * addr)2125 evutil_sockaddr_is_loopback(const struct sockaddr *addr)
2126 {
2127 	static const char LOOPBACK_S6[16] =
2128 	    "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\1";
2129 	if (addr->sa_family == AF_INET) {
2130 		struct sockaddr_in *sin = (struct sockaddr_in *)addr;
2131 		return (ntohl(sin->sin_addr.s_addr) & 0xff000000) == 0x7f000000;
2132 	} else if (addr->sa_family == AF_INET6) {
2133 		struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)addr;
2134 		return !memcmp(sin6->sin6_addr.s6_addr, LOOPBACK_S6, 16);
2135 	}
2136 	return 0;
2137 }
2138 
2139 #define MAX_SECONDS_IN_MSEC_LONG \
2140 	(((LONG_MAX) - 999) / 1000)
2141 
2142 long
evutil_tv_to_msec(const struct timeval * tv)2143 evutil_tv_to_msec(const struct timeval *tv)
2144 {
2145 	if (tv->tv_usec > 1000000 || tv->tv_sec > MAX_SECONDS_IN_MSEC_LONG)
2146 		return -1;
2147 
2148 	return (tv->tv_sec * 1000) + ((tv->tv_usec + 999) / 1000);
2149 }
2150 
2151 int
evutil_hex_char_to_int(char c)2152 evutil_hex_char_to_int(char c)
2153 {
2154 	switch(c)
2155 	{
2156 		case '0': return 0;
2157 		case '1': return 1;
2158 		case '2': return 2;
2159 		case '3': return 3;
2160 		case '4': return 4;
2161 		case '5': return 5;
2162 		case '6': return 6;
2163 		case '7': return 7;
2164 		case '8': return 8;
2165 		case '9': return 9;
2166 		case 'A': case 'a': return 10;
2167 		case 'B': case 'b': return 11;
2168 		case 'C': case 'c': return 12;
2169 		case 'D': case 'd': return 13;
2170 		case 'E': case 'e': return 14;
2171 		case 'F': case 'f': return 15;
2172 	}
2173 	return -1;
2174 }
2175 
2176 #ifdef WIN32
2177 HANDLE
evutil_load_windows_system_library(const TCHAR * library_name)2178 evutil_load_windows_system_library(const TCHAR *library_name)
2179 {
2180   TCHAR path[MAX_PATH];
2181   unsigned n;
2182   n = GetSystemDirectory(path, MAX_PATH);
2183   if (n == 0 || n + _tcslen(library_name) + 2 >= MAX_PATH)
2184     return 0;
2185   _tcscat(path, TEXT("\\"));
2186   _tcscat(path, library_name);
2187   return LoadLibrary(path);
2188 }
2189 #endif
2190 
2191