common.c revision 106040 
1/*-
2 * Copyright (c) 1998 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 106040 2002-10-27 15:08:21Z 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 <stdarg.h>
41#include <stdlib.h>
42#include <stdio.h>
43#include <string.h>
44#include <unistd.h>
45
46#include "fetch.h"
47#include "common.h"
48
49
50/*** Local data **************************************************************/
51
52/*
53 * Error messages for resolver errors
54 */
55static struct fetcherr _netdb_errlist[] = {
56	{ EAI_NODATA,	FETCH_RESOLV,	"Host not found" },
57	{ EAI_AGAIN,	FETCH_TEMP,	"Transient resolver failure" },
58	{ EAI_FAIL,	FETCH_RESOLV,	"Non-recoverable resolver failure" },
59	{ EAI_NONAME,	FETCH_RESOLV,	"No address record" },
60	{ -1,		FETCH_UNKNOWN,	"Unknown resolver error" }
61};
62
63/* End-of-Line */
64static const char ENDL[2] = "\r\n";
65
66
67/*** Error-reporting functions ***********************************************/
68
69/*
70 * Map error code to string
71 */
72static struct fetcherr *
73_fetch_finderr(struct fetcherr *p, int e)
74{
75	while (p->num != -1 && p->num != e)
76		p++;
77	return (p);
78}
79
80/*
81 * Set error code
82 */
83void
84_fetch_seterr(struct fetcherr *p, int e)
85{
86	p = _fetch_finderr(p, e);
87	fetchLastErrCode = p->cat;
88	snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string);
89}
90
91/*
92 * Set error code according to errno
93 */
94void
95_fetch_syserr(void)
96{
97	switch (errno) {
98	case 0:
99		fetchLastErrCode = FETCH_OK;
100		break;
101	case EPERM:
102	case EACCES:
103	case EROFS:
104	case EAUTH:
105	case ENEEDAUTH:
106		fetchLastErrCode = FETCH_AUTH;
107		break;
108	case ENOENT:
109	case EISDIR: /* XXX */
110		fetchLastErrCode = FETCH_UNAVAIL;
111		break;
112	case ENOMEM:
113		fetchLastErrCode = FETCH_MEMORY;
114		break;
115	case EBUSY:
116	case EAGAIN:
117		fetchLastErrCode = FETCH_TEMP;
118		break;
119	case EEXIST:
120		fetchLastErrCode = FETCH_EXISTS;
121		break;
122	case ENOSPC:
123		fetchLastErrCode = FETCH_FULL;
124		break;
125	case EADDRINUSE:
126	case EADDRNOTAVAIL:
127	case ENETDOWN:
128	case ENETUNREACH:
129	case ENETRESET:
130	case EHOSTUNREACH:
131		fetchLastErrCode = FETCH_NETWORK;
132		break;
133	case ECONNABORTED:
134	case ECONNRESET:
135		fetchLastErrCode = FETCH_ABORT;
136		break;
137	case ETIMEDOUT:
138		fetchLastErrCode = FETCH_TIMEOUT;
139		break;
140	case ECONNREFUSED:
141	case EHOSTDOWN:
142		fetchLastErrCode = FETCH_DOWN;
143		break;
144default:
145		fetchLastErrCode = FETCH_UNKNOWN;
146	}
147	snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno));
148}
149
150
151/*
152 * Emit status message
153 */
154void
155_fetch_info(const char *fmt, ...)
156{
157	va_list ap;
158
159	va_start(ap, fmt);
160	vfprintf(stderr, fmt, ap);
161	va_end(ap);
162	fputc('\n', stderr);
163}
164
165
166/*** Network-related utility functions ***************************************/
167
168/*
169 * Return the default port for a scheme
170 */
171int
172_fetch_default_port(const char *scheme)
173{
174	struct servent *se;
175
176	if ((se = getservbyname(scheme, "tcp")) != NULL)
177		return (ntohs(se->s_port));
178	if (strcasecmp(scheme, SCHEME_FTP) == 0)
179		return (FTP_DEFAULT_PORT);
180	if (strcasecmp(scheme, SCHEME_HTTP) == 0)
181		return (HTTP_DEFAULT_PORT);
182	return (0);
183}
184
185/*
186 * Return the default proxy port for a scheme
187 */
188int
189_fetch_default_proxy_port(const char *scheme)
190{
191	if (strcasecmp(scheme, SCHEME_FTP) == 0)
192		return (FTP_DEFAULT_PROXY_PORT);
193	if (strcasecmp(scheme, SCHEME_HTTP) == 0)
194		return (HTTP_DEFAULT_PROXY_PORT);
195	return (0);
196}
197
198
199/*
200 * Create a connection for an existing descriptor.
201 */
202conn_t *
203_fetch_reopen(int sd)
204{
205	conn_t *conn;
206
207	/* allocate and fill connection structure */
208	if ((conn = calloc(1, sizeof *conn)) == NULL)
209		return (NULL);
210	conn->sd = sd;
211	++conn->ref;
212	return (conn);
213}
214
215
216/*
217 * Bump a connection's reference count.
218 */
219conn_t *
220_fetch_ref(conn_t *conn)
221{
222
223	++conn->ref;
224	return (conn);
225}
226
227
228/*
229 * Establish a TCP connection to the specified port on the specified host.
230 */
231conn_t *
232_fetch_connect(const char *host, int port, int af, int verbose)
233{
234	conn_t *conn;
235	char pbuf[10];
236	struct addrinfo hints, *res, *res0;
237	int sd, err;
238
239	DEBUG(fprintf(stderr, "---> %s:%d\n", host, port));
240
241	if (verbose)
242		_fetch_info("looking up %s", host);
243
244	/* look up host name and set up socket address structure */
245	snprintf(pbuf, sizeof(pbuf), "%d", port);
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(host, pbuf, &hints, &res0)) != 0) {
251		_netdb_seterr(err);
252		return (NULL);
253	}
254
255	if (verbose)
256		_fetch_info("connecting to %s:%d", host, port);
257
258	/* try to connect */
259	for (sd = -1, res = res0; res; res = res->ai_next) {
260		if ((sd = socket(res->ai_family, res->ai_socktype,
261			 res->ai_protocol)) == -1)
262			continue;
263		if (connect(sd, res->ai_addr, res->ai_addrlen) != -1)
264			break;
265		close(sd);
266		sd = -1;
267	}
268	freeaddrinfo(res0);
269	if (sd == -1) {
270		_fetch_syserr();
271		return (NULL);
272	}
273
274	if ((conn = _fetch_reopen(sd)) == NULL) {
275		_fetch_syserr();
276		close(sd);
277	}
278	return (conn);
279}
280
281
282/*
283 * Enable SSL on a connection.
284 */
285int
286_fetch_ssl(conn_t *conn, int verbose)
287{
288
289#ifdef WITH_SSL
290	/* Init the SSL library and context */
291	if (!SSL_library_init()){
292		fprintf(stderr, "SSL library init failed\n");
293		return (-1);
294	}
295
296	SSL_load_error_strings();
297
298	conn->ssl_meth = SSLv23_client_method();
299	conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth);
300
301	conn->ssl = SSL_new(conn->ssl_ctx);
302	if (conn->ssl == NULL){
303		fprintf(stderr, "SSL context creation failed\n");
304		return (-1);
305	}
306	SSL_set_fd(conn->ssl, conn->sd);
307	if (SSL_connect(conn->ssl) == -1){
308		ERR_print_errors_fp(stderr);
309		return (-1);
310	}
311
312	if (verbose) {
313		X509_NAME *name;
314		char *str;
315
316		fprintf(stderr, "SSL connection established using %s\n",
317		    SSL_get_cipher(conn->ssl));
318		conn->ssl_cert = SSL_get_peer_certificate(conn->ssl);
319		name = X509_get_subject_name(conn->ssl_cert);
320		str = X509_NAME_oneline(name, 0, 0);
321		printf("Certificate subject: %s\n", str);
322		free(str);
323		name = X509_get_issuer_name(conn->ssl_cert);
324		str = X509_NAME_oneline(name, 0, 0);
325		printf("Certificate issuer: %s\n", str);
326		free(str);
327	}
328
329	return (0);
330#else
331	(void)conn;
332	(void)verbose;
333	fprintf(stderr, "SSL support disabled\n");
334	return (-1);
335#endif
336}
337
338
339/*
340 * Read a character from a connection w/ timeout
341 */
342ssize_t
343_fetch_read(conn_t *conn, char *buf, size_t len)
344{
345	struct timeval now, timeout, wait;
346	fd_set readfds;
347	ssize_t rlen, total;
348	int r;
349
350	if (fetchTimeout) {
351		FD_ZERO(&readfds);
352		gettimeofday(&timeout, NULL);
353		timeout.tv_sec += fetchTimeout;
354	}
355
356	total = 0;
357	while (len > 0) {
358		while (fetchTimeout && !FD_ISSET(conn->sd, &readfds)) {
359			FD_SET(conn->sd, &readfds);
360			gettimeofday(&now, NULL);
361			wait.tv_sec = timeout.tv_sec - now.tv_sec;
362			wait.tv_usec = timeout.tv_usec - now.tv_usec;
363			if (wait.tv_usec < 0) {
364				wait.tv_usec += 1000000;
365				wait.tv_sec--;
366			}
367			if (wait.tv_sec < 0) {
368				errno = ETIMEDOUT;
369				_fetch_syserr();
370				return (-1);
371			}
372			errno = 0;
373			r = select(conn->sd + 1, &readfds, NULL, NULL, &wait);
374			if (r == -1) {
375				if (errno == EINTR && fetchRestartCalls)
376					continue;
377				_fetch_syserr();
378				return (-1);
379			}
380		}
381#ifdef WITH_SSL
382		if (conn->ssl != NULL)
383			rlen = SSL_read(conn->ssl, buf, len);
384		else
385#endif
386			rlen = read(conn->sd, buf, len);
387		if (rlen == 0) {
388			/* we consider a short read a failure */
389			errno = EPIPE;
390			_fetch_syserr();
391			return (-1);
392		}
393		if (rlen < 0) {
394			if (errno == EINTR && fetchRestartCalls)
395				continue;
396			return (-1);
397		}
398		len -= rlen;
399		buf += rlen;
400		total += rlen;
401	}
402	return (total);
403}
404
405
406/*
407 * Read a line of text from a connection w/ timeout
408 */
409#define MIN_BUF_SIZE 1024
410
411int
412_fetch_getln(conn_t *conn)
413{
414	char *tmp;
415	size_t tmpsize;
416	char c;
417
418	if (conn->buf == NULL) {
419		if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
420			errno = ENOMEM;
421			return (-1);
422		}
423		conn->bufsize = MIN_BUF_SIZE;
424	}
425
426	conn->buf[0] = '\0';
427	conn->buflen = 0;
428
429	do {
430		if (_fetch_read(conn, &c, 1) == -1)
431			return (-1);
432		conn->buf[conn->buflen++] = c;
433		if (conn->buflen == conn->bufsize) {
434			tmp = conn->buf;
435			tmpsize = conn->bufsize * 2 + 1;
436			if ((tmp = realloc(tmp, tmpsize)) == NULL) {
437				errno = ENOMEM;
438				return (-1);
439			}
440			conn->buf = tmp;
441			conn->bufsize = tmpsize;
442		}
443	} while (c != '\n');
444
445	conn->buf[conn->buflen] = '\0';
446	DEBUG(fprintf(stderr, "<<< %s", conn->buf));
447	return (0);
448}
449
450
451/*
452 * Write to a connection w/ timeout
453 */
454ssize_t
455_fetch_write(conn_t *conn, const char *buf, size_t len)
456{
457	struct timeval now, timeout, wait;
458	fd_set writefds;
459	ssize_t wlen, total;
460	int r;
461
462	if (fetchTimeout) {
463		FD_ZERO(&writefds);
464		gettimeofday(&timeout, NULL);
465		timeout.tv_sec += fetchTimeout;
466	}
467
468	while (len > 0) {
469		while (fetchTimeout && !FD_ISSET(conn->sd, &writefds)) {
470			FD_SET(conn->sd, &writefds);
471			gettimeofday(&now, NULL);
472			wait.tv_sec = timeout.tv_sec - now.tv_sec;
473			wait.tv_usec = timeout.tv_usec - now.tv_usec;
474			if (wait.tv_usec < 0) {
475				wait.tv_usec += 1000000;
476				wait.tv_sec--;
477			}
478			if (wait.tv_sec < 0) {
479				errno = ETIMEDOUT;
480				_fetch_syserr();
481				return (-1);
482			}
483			errno = 0;
484			r = select(conn->sd + 1, NULL, &writefds, NULL, &wait);
485			if (r == -1) {
486				if (errno == EINTR && fetchRestartCalls)
487					continue;
488				return (-1);
489			}
490		}
491		errno = 0;
492#ifdef WITH_SSL
493		if (conn->ssl != NULL)
494			wlen = SSL_write(conn->ssl, buf, len);
495		else
496#endif
497			wlen = write(conn->sd, buf, len);
498		if (wlen == 0) {
499			/* we consider a short write a failure */
500			errno = EPIPE;
501			_fetch_syserr();
502			return (-1);
503		}
504		if (wlen < 0) {
505			if (errno == EINTR && fetchRestartCalls)
506				continue;
507			return (-1);
508		}
509		len -= wlen;
510		buf += wlen;
511		total += wlen;
512	}
513	return (total);
514}
515
516
517/*
518 * Write a line of text to a connection w/ timeout
519 */
520int
521_fetch_putln(conn_t *conn, const char *str, size_t len)
522{
523
524	DEBUG(fprintf(stderr, ">>> %s\n", str));
525	if (_fetch_write(conn, str, len) == -1 ||
526	    _fetch_write(conn, ENDL, sizeof ENDL) == -1)
527		return (-1);
528	return (0);
529}
530
531
532/*
533 * Close connection
534 */
535int
536_fetch_close(conn_t *conn)
537{
538	int ret;
539
540	if (--conn->ref > 0)
541		return (0);
542	ret = close(conn->sd);
543	free(conn);
544	return (ret);
545}
546
547
548/*** Directory-related utility functions *************************************/
549
550int
551_fetch_add_entry(struct url_ent **p, int *size, int *len,
552    const char *name, struct url_stat *us)
553{
554	struct url_ent *tmp;
555
556	if (*p == NULL) {
557		*size = 0;
558		*len = 0;
559	}
560
561	if (*len >= *size - 1) {
562		tmp = realloc(*p, (*size * 2 + 1) * sizeof **p);
563		if (tmp == NULL) {
564			errno = ENOMEM;
565			_fetch_syserr();
566			return (-1);
567		}
568		*size = (*size * 2 + 1);
569		*p = tmp;
570	}
571
572	tmp = *p + *len;
573	snprintf(tmp->name, PATH_MAX, "%s", name);
574	bcopy(us, &tmp->stat, sizeof *us);
575
576	(*len)++;
577	(++tmp)->name[0] = 0;
578
579	return (0);
580}
581