xref: /freebsd/lib/libfetch/common.c (revision c6ec7d31830ab1c80edae95ad5e4b9dba10c47ac) 
1 /*-
2  * Copyright (c) 1998-2011 Dag-Erling Smørgrav
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/socket.h>
34 #include <sys/time.h>
35 #include <sys/uio.h>
36 
37 #include <netinet/in.h>
38 
39 #include <ctype.h>
40 #include <errno.h>
41 #include <fcntl.h>
42 #include <netdb.h>
43 #include <pwd.h>
44 #include <stdarg.h>
45 #include <stdlib.h>
46 #include <stdio.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 #include "fetch.h"
51 #include "common.h"
52 
53 
54 /*** Local data **************************************************************/
55 
56 /*
57  * Error messages for resolver errors
58  */
59 static struct fetcherr netdb_errlist[] = {
60 #ifdef EAI_NODATA
61 	{ EAI_NODATA,	FETCH_RESOLV,	"Host not found" },
62 #endif
63 	{ EAI_AGAIN,	FETCH_TEMP,	"Transient resolver failure" },
64 	{ EAI_FAIL,	FETCH_RESOLV,	"Non-recoverable resolver failure" },
65 	{ EAI_NONAME,	FETCH_RESOLV,	"No address record" },
66 	{ -1,		FETCH_UNKNOWN,	"Unknown resolver error" }
67 };
68 
69 /* End-of-Line */
70 static const char ENDL[2] = "\r\n";
71 
72 
73 /*** Error-reporting functions ***********************************************/
74 
75 /*
76  * Map error code to string
77  */
78 static struct fetcherr *
79 fetch_finderr(struct fetcherr *p, int e)
80 {
81 	while (p->num != -1 && p->num != e)
82 		p++;
83 	return (p);
84 }
85 
86 /*
87  * Set error code
88  */
89 void
90 fetch_seterr(struct fetcherr *p, int e)
91 {
92 	p = fetch_finderr(p, e);
93 	fetchLastErrCode = p->cat;
94 	snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string);
95 }
96 
97 /*
98  * Set error code according to errno
99  */
100 void
101 fetch_syserr(void)
102 {
103 	switch (errno) {
104 	case 0:
105 		fetchLastErrCode = FETCH_OK;
106 		break;
107 	case EPERM:
108 	case EACCES:
109 	case EROFS:
110 	case EAUTH:
111 	case ENEEDAUTH:
112 		fetchLastErrCode = FETCH_AUTH;
113 		break;
114 	case ENOENT:
115 	case EISDIR: /* XXX */
116 		fetchLastErrCode = FETCH_UNAVAIL;
117 		break;
118 	case ENOMEM:
119 		fetchLastErrCode = FETCH_MEMORY;
120 		break;
121 	case EBUSY:
122 	case EAGAIN:
123 		fetchLastErrCode = FETCH_TEMP;
124 		break;
125 	case EEXIST:
126 		fetchLastErrCode = FETCH_EXISTS;
127 		break;
128 	case ENOSPC:
129 		fetchLastErrCode = FETCH_FULL;
130 		break;
131 	case EADDRINUSE:
132 	case EADDRNOTAVAIL:
133 	case ENETDOWN:
134 	case ENETUNREACH:
135 	case ENETRESET:
136 	case EHOSTUNREACH:
137 		fetchLastErrCode = FETCH_NETWORK;
138 		break;
139 	case ECONNABORTED:
140 	case ECONNRESET:
141 		fetchLastErrCode = FETCH_ABORT;
142 		break;
143 	case ETIMEDOUT:
144 		fetchLastErrCode = FETCH_TIMEOUT;
145 		break;
146 	case ECONNREFUSED:
147 	case EHOSTDOWN:
148 		fetchLastErrCode = FETCH_DOWN;
149 		break;
150 default:
151 		fetchLastErrCode = FETCH_UNKNOWN;
152 	}
153 	snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno));
154 }
155 
156 
157 /*
158  * Emit status message
159  */
160 void
161 fetch_info(const char *fmt, ...)
162 {
163 	va_list ap;
164 
165 	va_start(ap, fmt);
166 	vfprintf(stderr, fmt, ap);
167 	va_end(ap);
168 	fputc('\n', stderr);
169 }
170 
171 
172 /*** Network-related utility functions ***************************************/
173 
174 /*
175  * Return the default port for a scheme
176  */
177 int
178 fetch_default_port(const char *scheme)
179 {
180 	struct servent *se;
181 
182 	if ((se = getservbyname(scheme, "tcp")) != NULL)
183 		return (ntohs(se->s_port));
184 	if (strcasecmp(scheme, SCHEME_FTP) == 0)
185 		return (FTP_DEFAULT_PORT);
186 	if (strcasecmp(scheme, SCHEME_HTTP) == 0)
187 		return (HTTP_DEFAULT_PORT);
188 	return (0);
189 }
190 
191 /*
192  * Return the default proxy port for a scheme
193  */
194 int
195 fetch_default_proxy_port(const char *scheme)
196 {
197 	if (strcasecmp(scheme, SCHEME_FTP) == 0)
198 		return (FTP_DEFAULT_PROXY_PORT);
199 	if (strcasecmp(scheme, SCHEME_HTTP) == 0)
200 		return (HTTP_DEFAULT_PROXY_PORT);
201 	return (0);
202 }
203 
204 
205 /*
206  * Create a connection for an existing descriptor.
207  */
208 conn_t *
209 fetch_reopen(int sd)
210 {
211 	conn_t *conn;
212 	int opt = 1;
213 
214 	/* allocate and fill connection structure */
215 	if ((conn = calloc(1, sizeof(*conn))) == NULL)
216 		return (NULL);
217 	fcntl(sd, F_SETFD, FD_CLOEXEC);
218 	setsockopt(sd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof opt);
219 	conn->sd = sd;
220 	++conn->ref;
221 	return (conn);
222 }
223 
224 
225 /*
226  * Bump a connection's reference count.
227  */
228 conn_t *
229 fetch_ref(conn_t *conn)
230 {
231 
232 	++conn->ref;
233 	return (conn);
234 }
235 
236 
237 /*
238  * Bind a socket to a specific local address
239  */
240 int
241 fetch_bind(int sd, int af, const char *addr)
242 {
243 	struct addrinfo hints, *res, *res0;
244 	int err;
245 
246 	memset(&hints, 0, sizeof(hints));
247 	hints.ai_family = af;
248 	hints.ai_socktype = SOCK_STREAM;
249 	hints.ai_protocol = 0;
250 	if ((err = getaddrinfo(addr, NULL, &hints, &res0)) != 0)
251 		return (-1);
252 	for (res = res0; res; res = res->ai_next)
253 		if (bind(sd, res->ai_addr, res->ai_addrlen) == 0)
254 			return (0);
255 	return (-1);
256 }
257 
258 
259 /*
260  * Establish a TCP connection to the specified port on the specified host.
261  */
262 conn_t *
263 fetch_connect(const char *host, int port, int af, int verbose)
264 {
265 	conn_t *conn;
266 	char pbuf[10];
267 	const char *bindaddr;
268 	struct addrinfo hints, *res, *res0;
269 	int sd, err;
270 
271 	DEBUG(fprintf(stderr, "---> %s:%d\n", host, port));
272 
273 	if (verbose)
274 		fetch_info("looking up %s", host);
275 
276 	/* look up host name and set up socket address structure */
277 	snprintf(pbuf, sizeof(pbuf), "%d", port);
278 	memset(&hints, 0, sizeof(hints));
279 	hints.ai_family = af;
280 	hints.ai_socktype = SOCK_STREAM;
281 	hints.ai_protocol = 0;
282 	if ((err = getaddrinfo(host, pbuf, &hints, &res0)) != 0) {
283 		netdb_seterr(err);
284 		return (NULL);
285 	}
286 	bindaddr = getenv("FETCH_BIND_ADDRESS");
287 
288 	if (verbose)
289 		fetch_info("connecting to %s:%d", host, port);
290 
291 	/* try to connect */
292 	for (sd = -1, res = res0; res; sd = -1, res = res->ai_next) {
293 		if ((sd = socket(res->ai_family, res->ai_socktype,
294 			 res->ai_protocol)) == -1)
295 			continue;
296 		if (bindaddr != NULL && *bindaddr != '\0' &&
297 		    fetch_bind(sd, res->ai_family, bindaddr) != 0) {
298 			fetch_info("failed to bind to '%s'", bindaddr);
299 			close(sd);
300 			continue;
301 		}
302 		if (connect(sd, res->ai_addr, res->ai_addrlen) == 0 &&
303 		    fcntl(sd, F_SETFL, O_NONBLOCK) == 0)
304 			break;
305 		close(sd);
306 	}
307 	freeaddrinfo(res0);
308 	if (sd == -1) {
309 		fetch_syserr();
310 		return (NULL);
311 	}
312 
313 	if ((conn = fetch_reopen(sd)) == NULL) {
314 		fetch_syserr();
315 		close(sd);
316 	}
317 	return (conn);
318 }
319 
320 
321 /*
322  * Enable SSL on a connection.
323  */
324 int
325 fetch_ssl(conn_t *conn, int verbose)
326 {
327 #ifdef WITH_SSL
328 	int ret, ssl_err;
329 
330 	/* Init the SSL library and context */
331 	if (!SSL_library_init()){
332 		fprintf(stderr, "SSL library init failed\n");
333 		return (-1);
334 	}
335 
336 	SSL_load_error_strings();
337 
338 	conn->ssl_meth = SSLv23_client_method();
339 	conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth);
340 	SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY);
341 
342 	conn->ssl = SSL_new(conn->ssl_ctx);
343 	if (conn->ssl == NULL){
344 		fprintf(stderr, "SSL context creation failed\n");
345 		return (-1);
346 	}
347 	SSL_set_fd(conn->ssl, conn->sd);
348 	while ((ret = SSL_connect(conn->ssl)) == -1) {
349 		ssl_err = SSL_get_error(conn->ssl, ret);
350 		if (ssl_err != SSL_ERROR_WANT_READ &&
351 		    ssl_err != SSL_ERROR_WANT_WRITE) {
352 			ERR_print_errors_fp(stderr);
353 			return (-1);
354 		}
355 	}
356 
357 	if (verbose) {
358 		X509_NAME *name;
359 		char *str;
360 
361 		fprintf(stderr, "SSL connection established using %s\n",
362 		    SSL_get_cipher(conn->ssl));
363 		conn->ssl_cert = SSL_get_peer_certificate(conn->ssl);
364 		name = X509_get_subject_name(conn->ssl_cert);
365 		str = X509_NAME_oneline(name, 0, 0);
366 		printf("Certificate subject: %s\n", str);
367 		free(str);
368 		name = X509_get_issuer_name(conn->ssl_cert);
369 		str = X509_NAME_oneline(name, 0, 0);
370 		printf("Certificate issuer: %s\n", str);
371 		free(str);
372 	}
373 
374 	return (0);
375 #else
376 	(void)conn;
377 	(void)verbose;
378 	fprintf(stderr, "SSL support disabled\n");
379 	return (-1);
380 #endif
381 }
382 
383 #define FETCH_READ_WAIT		-2
384 #define FETCH_READ_ERROR	-1
385 #define FETCH_READ_DONE		 0
386 
387 #ifdef WITH_SSL
388 static ssize_t
389 fetch_ssl_read(SSL *ssl, char *buf, size_t len)
390 {
391 	ssize_t rlen;
392 	int ssl_err;
393 
394 	rlen = SSL_read(ssl, buf, len);
395 	if (rlen < 0) {
396 		ssl_err = SSL_get_error(ssl, rlen);
397 		if (ssl_err == SSL_ERROR_WANT_READ ||
398 		    ssl_err == SSL_ERROR_WANT_WRITE) {
399 			return (FETCH_READ_WAIT);
400 		} else {
401 			ERR_print_errors_fp(stderr);
402 			return (FETCH_READ_ERROR);
403 		}
404 	}
405 	return (rlen);
406 }
407 #endif
408 
409 /*
410  * Cache some data that was read from a socket but cannot be immediately
411  * returned because of an interrupted system call.
412  */
413 static int
414 fetch_cache_data(conn_t *conn, char *src, size_t nbytes)
415 {
416 	char *tmp;
417 
418 	if (conn->cache.size < nbytes) {
419 		tmp = realloc(conn->cache.buf, nbytes);
420 		if (tmp == NULL) {
421 			fetch_syserr();
422 			return (-1);
423 		}
424 		conn->cache.buf = tmp;
425 		conn->cache.size = nbytes;
426 	}
427 
428 	memcpy(conn->cache.buf, src, nbytes);
429 	conn->cache.len = nbytes;
430 	conn->cache.pos = 0;
431 
432 	return (0);
433 }
434 
435 
436 static ssize_t
437 fetch_socket_read(int sd, char *buf, size_t len)
438 {
439 	ssize_t rlen;
440 
441 	rlen = read(sd, buf, len);
442 	if (rlen < 0) {
443 		if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls))
444 			return (FETCH_READ_WAIT);
445 		else
446 			return (FETCH_READ_ERROR);
447 	}
448 	return (rlen);
449 }
450 
451 /*
452  * Read a character from a connection w/ timeout
453  */
454 ssize_t
455 fetch_read(conn_t *conn, char *buf, size_t len)
456 {
457 	struct timeval now, timeout, delta;
458 	fd_set readfds;
459 	ssize_t rlen, total;
460 	char *start;
461 
462 	if (fetchTimeout > 0) {
463 		gettimeofday(&timeout, NULL);
464 		timeout.tv_sec += fetchTimeout;
465 	}
466 
467 	total = 0;
468 	start = buf;
469 
470 	if (conn->cache.len > 0) {
471 		/*
472 		 * The last invocation of fetch_read was interrupted by a
473 		 * signal after some data had been read from the socket. Copy
474 		 * the cached data into the supplied buffer before trying to
475 		 * read from the socket again.
476 		 */
477 		total = (conn->cache.len < len) ? conn->cache.len : len;
478 		memcpy(buf, conn->cache.buf, total);
479 
480 		conn->cache.len -= total;
481 		conn->cache.pos += total;
482 		len -= total;
483 		buf += total;
484 	}
485 
486 	while (len > 0) {
487 		/*
488 		 * The socket is non-blocking.  Instead of the canonical
489 		 * select() -> read(), we do the following:
490 		 *
491 		 * 1) call read() or SSL_read().
492 		 * 2) if an error occurred, return -1.
493 		 * 3) if we received data but we still expect more,
494 		 *    update our counters and loop.
495 		 * 4) if read() or SSL_read() signaled EOF, return.
496 		 * 5) if we did not receive any data but we're not at EOF,
497 		 *    call select().
498 		 *
499 		 * In the SSL case, this is necessary because if we
500 		 * receive a close notification, we have to call
501 		 * SSL_read() one additional time after we've read
502 		 * everything we received.
503 		 *
504 		 * In the non-SSL case, it may improve performance (very
505 		 * slightly) when reading small amounts of data.
506 		 */
507 #ifdef WITH_SSL
508 		if (conn->ssl != NULL)
509 			rlen = fetch_ssl_read(conn->ssl, buf, len);
510 		else
511 #endif
512 			rlen = fetch_socket_read(conn->sd, buf, len);
513 		if (rlen == 0) {
514 			break;
515 		} else if (rlen > 0) {
516 			len -= rlen;
517 			buf += rlen;
518 			total += rlen;
519 			continue;
520 		} else if (rlen == FETCH_READ_ERROR) {
521 			if (errno == EINTR)
522 				fetch_cache_data(conn, start, total);
523 			return (-1);
524 		}
525 		// assert(rlen == FETCH_READ_WAIT);
526 		FD_ZERO(&readfds);
527 		while (!FD_ISSET(conn->sd, &readfds)) {
528 			FD_SET(conn->sd, &readfds);
529 			if (fetchTimeout > 0) {
530 				gettimeofday(&now, NULL);
531 				if (!timercmp(&timeout, &now, >)) {
532 					errno = ETIMEDOUT;
533 					fetch_syserr();
534 					return (-1);
535 				}
536 				timersub(&timeout, &now, &delta);
537 			}
538 			errno = 0;
539 			if (select(conn->sd + 1, &readfds, NULL, NULL,
540 				fetchTimeout > 0 ? &delta : NULL) < 0) {
541 				if (errno == EINTR) {
542 					if (fetchRestartCalls)
543 						continue;
544 					/* Save anything that was read. */
545 					fetch_cache_data(conn, start, total);
546 				}
547 				fetch_syserr();
548 				return (-1);
549 			}
550 		}
551 	}
552 	return (total);
553 }
554 
555 
556 /*
557  * Read a line of text from a connection w/ timeout
558  */
559 #define MIN_BUF_SIZE 1024
560 
561 int
562 fetch_getln(conn_t *conn)
563 {
564 	char *tmp;
565 	size_t tmpsize;
566 	ssize_t len;
567 	char c;
568 
569 	if (conn->buf == NULL) {
570 		if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
571 			errno = ENOMEM;
572 			return (-1);
573 		}
574 		conn->bufsize = MIN_BUF_SIZE;
575 	}
576 
577 	conn->buf[0] = '\0';
578 	conn->buflen = 0;
579 
580 	do {
581 		len = fetch_read(conn, &c, 1);
582 		if (len == -1)
583 			return (-1);
584 		if (len == 0)
585 			break;
586 		conn->buf[conn->buflen++] = c;
587 		if (conn->buflen == conn->bufsize) {
588 			tmp = conn->buf;
589 			tmpsize = conn->bufsize * 2 + 1;
590 			if ((tmp = realloc(tmp, tmpsize)) == NULL) {
591 				errno = ENOMEM;
592 				return (-1);
593 			}
594 			conn->buf = tmp;
595 			conn->bufsize = tmpsize;
596 		}
597 	} while (c != '\n');
598 
599 	conn->buf[conn->buflen] = '\0';
600 	DEBUG(fprintf(stderr, "<<< %s", conn->buf));
601 	return (0);
602 }
603 
604 
605 /*
606  * Write to a connection w/ timeout
607  */
608 ssize_t
609 fetch_write(conn_t *conn, const char *buf, size_t len)
610 {
611 	struct iovec iov;
612 
613 	iov.iov_base = __DECONST(char *, buf);
614 	iov.iov_len = len;
615 	return fetch_writev(conn, &iov, 1);
616 }
617 
618 /*
619  * Write a vector to a connection w/ timeout
620  * Note: can modify the iovec.
621  */
622 ssize_t
623 fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt)
624 {
625 	struct timeval now, timeout, delta;
626 	fd_set writefds;
627 	ssize_t wlen, total;
628 	int r;
629 
630 	if (fetchTimeout) {
631 		FD_ZERO(&writefds);
632 		gettimeofday(&timeout, NULL);
633 		timeout.tv_sec += fetchTimeout;
634 	}
635 
636 	total = 0;
637 	while (iovcnt > 0) {
638 		while (fetchTimeout && !FD_ISSET(conn->sd, &writefds)) {
639 			FD_SET(conn->sd, &writefds);
640 			gettimeofday(&now, NULL);
641 			delta.tv_sec = timeout.tv_sec - now.tv_sec;
642 			delta.tv_usec = timeout.tv_usec - now.tv_usec;
643 			if (delta.tv_usec < 0) {
644 				delta.tv_usec += 1000000;
645 				delta.tv_sec--;
646 			}
647 			if (delta.tv_sec < 0) {
648 				errno = ETIMEDOUT;
649 				fetch_syserr();
650 				return (-1);
651 			}
652 			errno = 0;
653 			r = select(conn->sd + 1, NULL, &writefds, NULL, &delta);
654 			if (r == -1) {
655 				if (errno == EINTR && fetchRestartCalls)
656 					continue;
657 				return (-1);
658 			}
659 		}
660 		errno = 0;
661 #ifdef WITH_SSL
662 		if (conn->ssl != NULL)
663 			wlen = SSL_write(conn->ssl,
664 			    iov->iov_base, iov->iov_len);
665 		else
666 #endif
667 			wlen = writev(conn->sd, iov, iovcnt);
668 		if (wlen == 0) {
669 			/* we consider a short write a failure */
670 			/* XXX perhaps we shouldn't in the SSL case */
671 			errno = EPIPE;
672 			fetch_syserr();
673 			return (-1);
674 		}
675 		if (wlen < 0) {
676 			if (errno == EINTR && fetchRestartCalls)
677 				continue;
678 			return (-1);
679 		}
680 		total += wlen;
681 		while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) {
682 			wlen -= iov->iov_len;
683 			iov++;
684 			iovcnt--;
685 		}
686 		if (iovcnt > 0) {
687 			iov->iov_len -= wlen;
688 			iov->iov_base = __DECONST(char *, iov->iov_base) + wlen;
689 		}
690 	}
691 	return (total);
692 }
693 
694 
695 /*
696  * Write a line of text to a connection w/ timeout
697  */
698 int
699 fetch_putln(conn_t *conn, const char *str, size_t len)
700 {
701 	struct iovec iov[2];
702 	int ret;
703 
704 	DEBUG(fprintf(stderr, ">>> %s\n", str));
705 	iov[0].iov_base = __DECONST(char *, str);
706 	iov[0].iov_len = len;
707 	iov[1].iov_base = __DECONST(char *, ENDL);
708 	iov[1].iov_len = sizeof(ENDL);
709 	if (len == 0)
710 		ret = fetch_writev(conn, &iov[1], 1);
711 	else
712 		ret = fetch_writev(conn, iov, 2);
713 	if (ret == -1)
714 		return (-1);
715 	return (0);
716 }
717 
718 
719 /*
720  * Close connection
721  */
722 int
723 fetch_close(conn_t *conn)
724 {
725 	int ret;
726 
727 	if (--conn->ref > 0)
728 		return (0);
729 	ret = close(conn->sd);
730 	free(conn->cache.buf);
731 	free(conn->buf);
732 	free(conn);
733 	return (ret);
734 }
735 
736 
737 /*** Directory-related utility functions *************************************/
738 
739 int
740 fetch_add_entry(struct url_ent **p, int *size, int *len,
741     const char *name, struct url_stat *us)
742 {
743 	struct url_ent *tmp;
744 
745 	if (*p == NULL) {
746 		*size = 0;
747 		*len = 0;
748 	}
749 
750 	if (*len >= *size - 1) {
751 		tmp = realloc(*p, (*size * 2 + 1) * sizeof(**p));
752 		if (tmp == NULL) {
753 			errno = ENOMEM;
754 			fetch_syserr();
755 			return (-1);
756 		}
757 		*size = (*size * 2 + 1);
758 		*p = tmp;
759 	}
760 
761 	tmp = *p + *len;
762 	snprintf(tmp->name, PATH_MAX, "%s", name);
763 	memcpy(&tmp->stat, us, sizeof(*us));
764 
765 	(*len)++;
766 	(++tmp)->name[0] = 0;
767 
768 	return (0);
769 }
770 
771 
772 /*** Authentication-related utility functions ********************************/
773 
774 static const char *
775 fetch_read_word(FILE *f)
776 {
777 	static char word[1024];
778 
779 	if (fscanf(f, " %1023s ", word) != 1)
780 		return (NULL);
781 	return (word);
782 }
783 
784 /*
785  * Get authentication data for a URL from .netrc
786  */
787 int
788 fetch_netrc_auth(struct url *url)
789 {
790 	char fn[PATH_MAX];
791 	const char *word;
792 	char *p;
793 	FILE *f;
794 
795 	if ((p = getenv("NETRC")) != NULL) {
796 		if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) {
797 			fetch_info("$NETRC specifies a file name "
798 			    "longer than PATH_MAX");
799 			return (-1);
800 		}
801 	} else {
802 		if ((p = getenv("HOME")) != NULL) {
803 			struct passwd *pwd;
804 
805 			if ((pwd = getpwuid(getuid())) == NULL ||
806 			    (p = pwd->pw_dir) == NULL)
807 				return (-1);
808 		}
809 		if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn))
810 			return (-1);
811 	}
812 
813 	if ((f = fopen(fn, "r")) == NULL)
814 		return (-1);
815 	while ((word = fetch_read_word(f)) != NULL) {
816 		if (strcmp(word, "default") == 0) {
817 			DEBUG(fetch_info("Using default .netrc settings"));
818 			break;
819 		}
820 		if (strcmp(word, "machine") == 0 &&
821 		    (word = fetch_read_word(f)) != NULL &&
822 		    strcasecmp(word, url->host) == 0) {
823 			DEBUG(fetch_info("Using .netrc settings for %s", word));
824 			break;
825 		}
826 	}
827 	if (word == NULL)
828 		goto ferr;
829 	while ((word = fetch_read_word(f)) != NULL) {
830 		if (strcmp(word, "login") == 0) {
831 			if ((word = fetch_read_word(f)) == NULL)
832 				goto ferr;
833 			if (snprintf(url->user, sizeof(url->user),
834 				"%s", word) > (int)sizeof(url->user)) {
835 				fetch_info("login name in .netrc is too long");
836 				url->user[0] = '\0';
837 			}
838 		} else if (strcmp(word, "password") == 0) {
839 			if ((word = fetch_read_word(f)) == NULL)
840 				goto ferr;
841 			if (snprintf(url->pwd, sizeof(url->pwd),
842 				"%s", word) > (int)sizeof(url->pwd)) {
843 				fetch_info("password in .netrc is too long");
844 				url->pwd[0] = '\0';
845 			}
846 		} else if (strcmp(word, "account") == 0) {
847 			if ((word = fetch_read_word(f)) == NULL)
848 				goto ferr;
849 			/* XXX not supported! */
850 		} else {
851 			break;
852 		}
853 	}
854 	fclose(f);
855 	return (0);
856  ferr:
857 	fclose(f);
858 	return (-1);
859 }
860 
861 /*
862  * The no_proxy environment variable specifies a set of domains for
863  * which the proxy should not be consulted; the contents is a comma-,
864  * or space-separated list of domain names.  A single asterisk will
865  * override all proxy variables and no transactions will be proxied
866  * (for compatability with lynx and curl, see the discussion at
867  * <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>).
868  */
869 int
870 fetch_no_proxy_match(const char *host)
871 {
872 	const char *no_proxy, *p, *q;
873 	size_t h_len, d_len;
874 
875 	if ((no_proxy = getenv("NO_PROXY")) == NULL &&
876 	    (no_proxy = getenv("no_proxy")) == NULL)
877 		return (0);
878 
879 	/* asterisk matches any hostname */
880 	if (strcmp(no_proxy, "*") == 0)
881 		return (1);
882 
883 	h_len = strlen(host);
884 	p = no_proxy;
885 	do {
886 		/* position p at the beginning of a domain suffix */
887 		while (*p == ',' || isspace((unsigned char)*p))
888 			p++;
889 
890 		/* position q at the first separator character */
891 		for (q = p; *q; ++q)
892 			if (*q == ',' || isspace((unsigned char)*q))
893 				break;
894 
895 		d_len = q - p;
896 		if (d_len > 0 && h_len >= d_len &&
897 		    strncasecmp(host + h_len - d_len,
898 			p, d_len) == 0) {
899 			/* domain name matches */
900 			return (1);
901 		}
902 
903 		p = q + 1;
904 	} while (*q);
905 
906 	return (0);
907 }
908