common.c revision 141970 
1/*-
2 * Copyright (c) 1998-2004 Dag-Erling Co�dan Sm�rgrav
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: head/lib/libfetch/common.c 141970 2005-02-16 12:46:46Z des $");
31
32#include <sys/param.h>
33#include <sys/socket.h>
34#include <sys/time.h>
35#include <sys/uio.h>
36#include <netinet/in.h>
37
38#include <errno.h>
39#include <netdb.h>
40#include <pwd.h>
41#include <stdarg.h>
42#include <stdlib.h>
43#include <stdio.h>
44#include <string.h>
45#include <unistd.h>
46
47#include "fetch.h"
48#include "common.h"
49
50
51/*** Local data **************************************************************/
52
53/*
54 * Error messages for resolver errors
55 */
56static struct fetcherr _netdb_errlist[] = {
57#ifdef EAI_NODATA
58	{ EAI_NODATA,	FETCH_RESOLV,	"Host not found" },
59#endif
60	{ EAI_AGAIN,	FETCH_TEMP,	"Transient resolver failure" },
61	{ EAI_FAIL,	FETCH_RESOLV,	"Non-recoverable resolver failure" },
62	{ EAI_NONAME,	FETCH_RESOLV,	"No address record" },
63	{ -1,		FETCH_UNKNOWN,	"Unknown resolver error" }
64};
65
66/* End-of-Line */
67static const char ENDL[2] = "\r\n";
68
69
70/*** Error-reporting functions ***********************************************/
71
72/*
73 * Map error code to string
74 */
75static struct fetcherr *
76_fetch_finderr(struct fetcherr *p, int e)
77{
78	while (p->num != -1 && p->num != e)
79		p++;
80	return (p);
81}
82
83/*
84 * Set error code
85 */
86void
87_fetch_seterr(struct fetcherr *p, int e)
88{
89	p = _fetch_finderr(p, e);
90	fetchLastErrCode = p->cat;
91	snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string);
92}
93
94/*
95 * Set error code according to errno
96 */
97void
98_fetch_syserr(void)
99{
100	switch (errno) {
101	case 0:
102		fetchLastErrCode = FETCH_OK;
103		break;
104	case EPERM:
105	case EACCES:
106	case EROFS:
107	case EAUTH:
108	case ENEEDAUTH:
109		fetchLastErrCode = FETCH_AUTH;
110		break;
111	case ENOENT:
112	case EISDIR: /* XXX */
113		fetchLastErrCode = FETCH_UNAVAIL;
114		break;
115	case ENOMEM:
116		fetchLastErrCode = FETCH_MEMORY;
117		break;
118	case EBUSY:
119	case EAGAIN:
120		fetchLastErrCode = FETCH_TEMP;
121		break;
122	case EEXIST:
123		fetchLastErrCode = FETCH_EXISTS;
124		break;
125	case ENOSPC:
126		fetchLastErrCode = FETCH_FULL;
127		break;
128	case EADDRINUSE:
129	case EADDRNOTAVAIL:
130	case ENETDOWN:
131	case ENETUNREACH:
132	case ENETRESET:
133	case EHOSTUNREACH:
134		fetchLastErrCode = FETCH_NETWORK;
135		break;
136	case ECONNABORTED:
137	case ECONNRESET:
138		fetchLastErrCode = FETCH_ABORT;
139		break;
140	case ETIMEDOUT:
141		fetchLastErrCode = FETCH_TIMEOUT;
142		break;
143	case ECONNREFUSED:
144	case EHOSTDOWN:
145		fetchLastErrCode = FETCH_DOWN;
146		break;
147default:
148		fetchLastErrCode = FETCH_UNKNOWN;
149	}
150	snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno));
151}
152
153
154/*
155 * Emit status message
156 */
157void
158_fetch_info(const char *fmt, ...)
159{
160	va_list ap;
161
162	va_start(ap, fmt);
163	vfprintf(stderr, fmt, ap);
164	va_end(ap);
165	fputc('\n', stderr);
166}
167
168
169/*** Network-related utility functions ***************************************/
170
171/*
172 * Return the default port for a scheme
173 */
174int
175_fetch_default_port(const char *scheme)
176{
177	struct servent *se;
178
179	if ((se = getservbyname(scheme, "tcp")) != NULL)
180		return (ntohs(se->s_port));
181	if (strcasecmp(scheme, SCHEME_FTP) == 0)
182		return (FTP_DEFAULT_PORT);
183	if (strcasecmp(scheme, SCHEME_HTTP) == 0)
184		return (HTTP_DEFAULT_PORT);
185	return (0);
186}
187
188/*
189 * Return the default proxy port for a scheme
190 */
191int
192_fetch_default_proxy_port(const char *scheme)
193{
194	if (strcasecmp(scheme, SCHEME_FTP) == 0)
195		return (FTP_DEFAULT_PROXY_PORT);
196	if (strcasecmp(scheme, SCHEME_HTTP) == 0)
197		return (HTTP_DEFAULT_PROXY_PORT);
198	return (0);
199}
200
201
202/*
203 * Create a connection for an existing descriptor.
204 */
205conn_t *
206_fetch_reopen(int sd)
207{
208	conn_t *conn;
209
210	/* allocate and fill connection structure */
211	if ((conn = calloc(1, sizeof(*conn))) == NULL)
212		return (NULL);
213	conn->sd = sd;
214	++conn->ref;
215	return (conn);
216}
217
218
219/*
220 * Bump a connection's reference count.
221 */
222conn_t *
223_fetch_ref(conn_t *conn)
224{
225
226	++conn->ref;
227	return (conn);
228}
229
230
231/*
232 * Bind a socket to a specific local address
233 */
234int
235_fetch_bind(int sd, int af, const char *addr)
236{
237	struct addrinfo hints, *res, *res0;
238	int err;
239
240	memset(&hints, 0, sizeof(hints));
241	hints.ai_family = af;
242	hints.ai_socktype = SOCK_STREAM;
243	hints.ai_protocol = 0;
244	if ((err = getaddrinfo(addr, NULL, &hints, &res0)) != 0)
245		return (-1);
246	for (res = res0; res; res = res->ai_next)
247		if (bind(sd, res->ai_addr, res->ai_addrlen) == 0)
248			return (0);
249	return (-1);
250}
251
252
253/*
254 * Establish a TCP connection to the specified port on the specified host.
255 */
256conn_t *
257_fetch_connect(const char *host, int port, int af, int verbose)
258{
259	conn_t *conn;
260	char pbuf[10];
261	const char *bindaddr;
262	struct addrinfo hints, *res, *res0;
263	int sd, err;
264
265	DEBUG(fprintf(stderr, "---> %s:%d\n", host, port));
266
267	if (verbose)
268		_fetch_info("looking up %s", host);
269
270	/* look up host name and set up socket address structure */
271	snprintf(pbuf, sizeof(pbuf), "%d", port);
272	memset(&hints, 0, sizeof(hints));
273	hints.ai_family = af;
274	hints.ai_socktype = SOCK_STREAM;
275	hints.ai_protocol = 0;
276	if ((err = getaddrinfo(host, pbuf, &hints, &res0)) != 0) {
277		_netdb_seterr(err);
278		return (NULL);
279	}
280	bindaddr = getenv("FETCH_BIND_ADDRESS");
281
282	if (verbose)
283		_fetch_info("connecting to %s:%d", host, port);
284
285	/* try to connect */
286	for (sd = -1, res = res0; res; sd = -1, res = res->ai_next) {
287		if ((sd = socket(res->ai_family, res->ai_socktype,
288			 res->ai_protocol)) == -1)
289			continue;
290		if (bindaddr != NULL && *bindaddr != '\0' &&
291		    _fetch_bind(sd, res->ai_family, bindaddr) != 0) {
292			_fetch_info("failed to bind to '%s'", bindaddr);
293			close(sd);
294			continue;
295		}
296		if (connect(sd, res->ai_addr, res->ai_addrlen) == 0)
297			break;
298		close(sd);
299	}
300	freeaddrinfo(res0);
301	if (sd == -1) {
302		_fetch_syserr();
303		return (NULL);
304	}
305
306	if ((conn = _fetch_reopen(sd)) == NULL) {
307		_fetch_syserr();
308		close(sd);
309	}
310	return (conn);
311}
312
313
314/*
315 * Enable SSL on a connection.
316 */
317int
318_fetch_ssl(conn_t *conn, int verbose)
319{
320
321#ifdef WITH_SSL
322	/* Init the SSL library and context */
323	if (!SSL_library_init()){
324		fprintf(stderr, "SSL library init failed\n");
325		return (-1);
326	}
327
328	SSL_load_error_strings();
329
330	conn->ssl_meth = SSLv23_client_method();
331	conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth);
332	SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY);
333
334	conn->ssl = SSL_new(conn->ssl_ctx);
335	if (conn->ssl == NULL){
336		fprintf(stderr, "SSL context creation failed\n");
337		return (-1);
338	}
339	SSL_set_fd(conn->ssl, conn->sd);
340	if (SSL_connect(conn->ssl) == -1){
341		ERR_print_errors_fp(stderr);
342		return (-1);
343	}
344
345	if (verbose) {
346		X509_NAME *name;
347		char *str;
348
349		fprintf(stderr, "SSL connection established using %s\n",
350		    SSL_get_cipher(conn->ssl));
351		conn->ssl_cert = SSL_get_peer_certificate(conn->ssl);
352		name = X509_get_subject_name(conn->ssl_cert);
353		str = X509_NAME_oneline(name, 0, 0);
354		printf("Certificate subject: %s\n", str);
355		free(str);
356		name = X509_get_issuer_name(conn->ssl_cert);
357		str = X509_NAME_oneline(name, 0, 0);
358		printf("Certificate issuer: %s\n", str);
359		free(str);
360	}
361
362	return (0);
363#else
364	(void)conn;
365	(void)verbose;
366	fprintf(stderr, "SSL support disabled\n");
367	return (-1);
368#endif
369}
370
371
372/*
373 * Read a character from a connection w/ timeout
374 */
375ssize_t
376_fetch_read(conn_t *conn, char *buf, size_t len)
377{
378	struct timeval now, timeout, wait;
379	fd_set readfds;
380	ssize_t rlen, total;
381	int r;
382
383	if (fetchTimeout) {
384		FD_ZERO(&readfds);
385		gettimeofday(&timeout, NULL);
386		timeout.tv_sec += fetchTimeout;
387	}
388
389	total = 0;
390	while (len > 0) {
391		while (fetchTimeout && !FD_ISSET(conn->sd, &readfds)) {
392			FD_SET(conn->sd, &readfds);
393			gettimeofday(&now, NULL);
394			wait.tv_sec = timeout.tv_sec - now.tv_sec;
395			wait.tv_usec = timeout.tv_usec - now.tv_usec;
396			if (wait.tv_usec < 0) {
397				wait.tv_usec += 1000000;
398				wait.tv_sec--;
399			}
400			if (wait.tv_sec < 0) {
401				errno = ETIMEDOUT;
402				_fetch_syserr();
403				return (-1);
404			}
405			errno = 0;
406			r = select(conn->sd + 1, &readfds, NULL, NULL, &wait);
407			if (r == -1) {
408				if (errno == EINTR && fetchRestartCalls)
409					continue;
410				_fetch_syserr();
411				return (-1);
412			}
413		}
414#ifdef WITH_SSL
415		if (conn->ssl != NULL)
416			rlen = SSL_read(conn->ssl, buf, len);
417		else
418#endif
419			rlen = read(conn->sd, buf, len);
420		if (rlen == 0)
421			break;
422		if (rlen < 0) {
423			if (errno == EINTR && fetchRestartCalls)
424				continue;
425			return (-1);
426		}
427		len -= rlen;
428		buf += rlen;
429		total += rlen;
430	}
431	return (total);
432}
433
434
435/*
436 * Read a line of text from a connection w/ timeout
437 */
438#define MIN_BUF_SIZE 1024
439
440int
441_fetch_getln(conn_t *conn)
442{
443	char *tmp;
444	size_t tmpsize;
445	ssize_t len;
446	char c;
447
448	if (conn->buf == NULL) {
449		if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
450			errno = ENOMEM;
451			return (-1);
452		}
453		conn->bufsize = MIN_BUF_SIZE;
454	}
455
456	conn->buf[0] = '\0';
457	conn->buflen = 0;
458
459	do {
460		len = _fetch_read(conn, &c, 1);
461		if (len == -1)
462			return (-1);
463		if (len == 0)
464			break;
465		conn->buf[conn->buflen++] = c;
466		if (conn->buflen == conn->bufsize) {
467			tmp = conn->buf;
468			tmpsize = conn->bufsize * 2 + 1;
469			if ((tmp = realloc(tmp, tmpsize)) == NULL) {
470				errno = ENOMEM;
471				return (-1);
472			}
473			conn->buf = tmp;
474			conn->bufsize = tmpsize;
475		}
476	} while (c != '\n');
477
478	conn->buf[conn->buflen] = '\0';
479	DEBUG(fprintf(stderr, "<<< %s", conn->buf));
480	return (0);
481}
482
483
484/*
485 * Write to a connection w/ timeout
486 */
487ssize_t
488_fetch_write(conn_t *conn, const char *buf, size_t len)
489{
490	struct iovec iov;
491
492	iov.iov_base = __DECONST(char *, buf);
493	iov.iov_len = len;
494	return _fetch_writev(conn, &iov, 1);
495}
496
497/*
498 * Write a vector to a connection w/ timeout
499 * Note: can modify the iovec.
500 */
501ssize_t
502_fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt)
503{
504	struct timeval now, timeout, wait;
505	fd_set writefds;
506	ssize_t wlen, total;
507	int r;
508
509	if (fetchTimeout) {
510		FD_ZERO(&writefds);
511		gettimeofday(&timeout, NULL);
512		timeout.tv_sec += fetchTimeout;
513	}
514
515	total = 0;
516	while (iovcnt > 0) {
517		while (fetchTimeout && !FD_ISSET(conn->sd, &writefds)) {
518			FD_SET(conn->sd, &writefds);
519			gettimeofday(&now, NULL);
520			wait.tv_sec = timeout.tv_sec - now.tv_sec;
521			wait.tv_usec = timeout.tv_usec - now.tv_usec;
522			if (wait.tv_usec < 0) {
523				wait.tv_usec += 1000000;
524				wait.tv_sec--;
525			}
526			if (wait.tv_sec < 0) {
527				errno = ETIMEDOUT;
528				_fetch_syserr();
529				return (-1);
530			}
531			errno = 0;
532			r = select(conn->sd + 1, NULL, &writefds, NULL, &wait);
533			if (r == -1) {
534				if (errno == EINTR && fetchRestartCalls)
535					continue;
536				return (-1);
537			}
538		}
539		errno = 0;
540#ifdef WITH_SSL
541		if (conn->ssl != NULL)
542			wlen = SSL_write(conn->ssl,
543			    iov->iov_base, iov->iov_len);
544		else
545#endif
546			wlen = writev(conn->sd, iov, iovcnt);
547		if (wlen == 0) {
548			/* we consider a short write a failure */
549			errno = EPIPE;
550			_fetch_syserr();
551			return (-1);
552		}
553		if (wlen < 0) {
554			if (errno == EINTR && fetchRestartCalls)
555				continue;
556			return (-1);
557		}
558		total += wlen;
559		while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) {
560			wlen -= iov->iov_len;
561			iov++;
562			iovcnt--;
563		}
564		if (iovcnt > 0) {
565			iov->iov_len -= wlen;
566			iov->iov_base = __DECONST(char *, iov->iov_base) + wlen;
567		}
568	}
569	return (total);
570}
571
572
573/*
574 * Write a line of text to a connection w/ timeout
575 */
576int
577_fetch_putln(conn_t *conn, const char *str, size_t len)
578{
579	struct iovec iov[2];
580	int ret;
581
582	DEBUG(fprintf(stderr, ">>> %s\n", str));
583	iov[0].iov_base = __DECONST(char *, str);
584	iov[0].iov_len = len;
585	iov[1].iov_base = __DECONST(char *, ENDL);
586	iov[1].iov_len = sizeof(ENDL);
587	if (len == 0)
588		ret = _fetch_writev(conn, &iov[1], 1);
589	else
590		ret = _fetch_writev(conn, iov, 2);
591	if (ret == -1)
592		return (-1);
593	return (0);
594}
595
596
597/*
598 * Close connection
599 */
600int
601_fetch_close(conn_t *conn)
602{
603	int ret;
604
605	if (--conn->ref > 0)
606		return (0);
607	ret = close(conn->sd);
608	free(conn->buf);
609	free(conn);
610	return (ret);
611}
612
613
614/*** Directory-related utility functions *************************************/
615
616int
617_fetch_add_entry(struct url_ent **p, int *size, int *len,
618    const char *name, struct url_stat *us)
619{
620	struct url_ent *tmp;
621
622	if (*p == NULL) {
623		*size = 0;
624		*len = 0;
625	}
626
627	if (*len >= *size - 1) {
628		tmp = realloc(*p, (*size * 2 + 1) * sizeof(**p));
629		if (tmp == NULL) {
630			errno = ENOMEM;
631			_fetch_syserr();
632			return (-1);
633		}
634		*size = (*size * 2 + 1);
635		*p = tmp;
636	}
637
638	tmp = *p + *len;
639	snprintf(tmp->name, PATH_MAX, "%s", name);
640	bcopy(us, &tmp->stat, sizeof(*us));
641
642	(*len)++;
643	(++tmp)->name[0] = 0;
644
645	return (0);
646}
647
648
649/*** Authentication-related utility functions ********************************/
650
651static const char *
652_fetch_read_word(FILE *f)
653{
654	static char word[1024];
655
656	if (fscanf(f, " %1024s ", word) != 1)
657		return (NULL);
658	return (word);
659}
660
661/*
662 * Get authentication data for a URL from .netrc
663 */
664int
665_fetch_netrc_auth(struct url *url)
666{
667	char fn[PATH_MAX];
668	const char *word;
669	char *p;
670	FILE *f;
671
672	if ((p = getenv("NETRC")) != NULL) {
673		if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) {
674			_fetch_info("$NETRC specifies a file name "
675			    "longer than PATH_MAX");
676			return (-1);
677		}
678	} else {
679		if ((p = getenv("HOME")) != NULL) {
680			struct passwd *pwd;
681
682			if ((pwd = getpwuid(getuid())) == NULL ||
683			    (p = pwd->pw_dir) == NULL)
684				return (-1);
685		}
686		if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn))
687			return (-1);
688	}
689
690	if ((f = fopen(fn, "r")) == NULL)
691		return (-1);
692	while ((word = _fetch_read_word(f)) != NULL) {
693		if (strcmp(word, "default") == 0) {
694			DEBUG(_fetch_info("Using default .netrc settings"));
695			break;
696		}
697		if (strcmp(word, "machine") == 0 &&
698		    (word = _fetch_read_word(f)) != NULL &&
699		    strcasecmp(word, url->host) == 0) {
700			DEBUG(_fetch_info("Using .netrc settings for %s", word));
701			break;
702		}
703	}
704	if (word == NULL)
705		goto ferr;
706	while ((word = _fetch_read_word(f)) != NULL) {
707		if (strcmp(word, "login") == 0) {
708			if ((word = _fetch_read_word(f)) == NULL)
709				goto ferr;
710			if (snprintf(url->user, sizeof(url->user),
711				"%s", word) > (int)sizeof(url->user)) {
712				_fetch_info("login name in .netrc is too long");
713				url->user[0] = '\0';
714			}
715		} else if (strcmp(word, "password") == 0) {
716			if ((word = _fetch_read_word(f)) == NULL)
717				goto ferr;
718			if (snprintf(url->pwd, sizeof(url->pwd),
719				"%s", word) > (int)sizeof(url->pwd)) {
720				_fetch_info("password in .netrc is too long");
721				url->pwd[0] = '\0';
722			}
723		} else if (strcmp(word, "account") == 0) {
724			if ((word = _fetch_read_word(f)) == NULL)
725				goto ferr;
726			/* XXX not supported! */
727		} else {
728			break;
729		}
730	}
731	fclose(f);
732	return (0);
733 ferr:
734	fclose(f);
735	return (-1);
736}
737