common.c revision 106205 
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 106205 2002-10-30 14:25:00Z 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			break;
389		if (rlen < 0) {
390			if (errno == EINTR && fetchRestartCalls)
391				continue;
392			return (-1);
393		}
394		len -= rlen;
395		buf += rlen;
396		total += rlen;
397	}
398	return (total);
399}
400
401
402/*
403 * Read a line of text from a connection w/ timeout
404 */
405#define MIN_BUF_SIZE 1024
406
407int
408_fetch_getln(conn_t *conn)
409{
410	char *tmp;
411	size_t tmpsize;
412	ssize_t len;
413	char c;
414
415	if (conn->buf == NULL) {
416		if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
417			errno = ENOMEM;
418			return (-1);
419		}
420		conn->bufsize = MIN_BUF_SIZE;
421	}
422
423	conn->buf[0] = '\0';
424	conn->buflen = 0;
425
426	do {
427		len = _fetch_read(conn, &c, 1);
428		if (len == -1)
429			return (-1);
430		if (len == 0)
431			break;
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 iovec iov;
458
459	iov.iov_base = __DECONST(char *, buf);
460	iov.iov_len = len;
461	return _fetch_writev(conn, &iov, 1);
462}
463
464/*
465 * Write a vector to a connection w/ timeout
466 * Note: can modify the iovec.
467 */
468ssize_t
469_fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt)
470{
471	struct timeval now, timeout, wait;
472	fd_set writefds;
473	ssize_t wlen, total;
474	int r;
475
476	if (fetchTimeout) {
477		FD_ZERO(&writefds);
478		gettimeofday(&timeout, NULL);
479		timeout.tv_sec += fetchTimeout;
480	}
481
482	total = 0;
483	while (iovcnt > 0) {
484		while (fetchTimeout && !FD_ISSET(conn->sd, &writefds)) {
485			FD_SET(conn->sd, &writefds);
486			gettimeofday(&now, NULL);
487			wait.tv_sec = timeout.tv_sec - now.tv_sec;
488			wait.tv_usec = timeout.tv_usec - now.tv_usec;
489			if (wait.tv_usec < 0) {
490				wait.tv_usec += 1000000;
491				wait.tv_sec--;
492			}
493			if (wait.tv_sec < 0) {
494				errno = ETIMEDOUT;
495				_fetch_syserr();
496				return (-1);
497			}
498			errno = 0;
499			r = select(conn->sd + 1, NULL, &writefds, NULL, &wait);
500			if (r == -1) {
501				if (errno == EINTR && fetchRestartCalls)
502					continue;
503				return (-1);
504			}
505		}
506		errno = 0;
507#ifdef WITH_SSL
508		if (conn->ssl != NULL)
509			wlen = SSL_write(conn->ssl,
510			    iov->iov_base, iov->iov_len);
511		else
512#endif
513			wlen = writev(conn->sd, iov, iovcnt);
514		if (wlen == 0) {
515			/* we consider a short write a failure */
516			errno = EPIPE;
517			_fetch_syserr();
518			return (-1);
519		}
520		if (wlen < 0) {
521			if (errno == EINTR && fetchRestartCalls)
522				continue;
523			return (-1);
524		}
525		total += wlen;
526		while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) {
527			wlen -= iov->iov_len;
528			iov++;
529			iovcnt--;
530		}
531		if (iovcnt > 0) {
532			iov->iov_len -= wlen;
533			iov->iov_base = __DECONST(char *, iov->iov_base) + wlen;
534		}
535	}
536	return (total);
537}
538
539
540/*
541 * Write a line of text to a connection w/ timeout
542 */
543int
544_fetch_putln(conn_t *conn, const char *str, size_t len)
545{
546	struct iovec iov[2];
547	int ret;
548
549	DEBUG(fprintf(stderr, ">>> %s\n", str));
550	iov[0].iov_base = __DECONST(char *, str);
551	iov[0].iov_len = len;
552	iov[1].iov_base = __DECONST(char *, ENDL);
553	iov[1].iov_len = sizeof ENDL;
554	if (len == 0)
555		ret = _fetch_writev(conn, &iov[1], 1);
556	else
557		ret = _fetch_writev(conn, iov, 2);
558	if (ret == -1)
559		return (-1);
560	return (0);
561}
562
563
564/*
565 * Close connection
566 */
567int
568_fetch_close(conn_t *conn)
569{
570	int ret;
571
572	if (--conn->ref > 0)
573		return (0);
574	ret = close(conn->sd);
575	free(conn);
576	return (ret);
577}
578
579
580/*** Directory-related utility functions *************************************/
581
582int
583_fetch_add_entry(struct url_ent **p, int *size, int *len,
584    const char *name, struct url_stat *us)
585{
586	struct url_ent *tmp;
587
588	if (*p == NULL) {
589		*size = 0;
590		*len = 0;
591	}
592
593	if (*len >= *size - 1) {
594		tmp = realloc(*p, (*size * 2 + 1) * sizeof **p);
595		if (tmp == NULL) {
596			errno = ENOMEM;
597			_fetch_syserr();
598			return (-1);
599		}
600		*size = (*size * 2 + 1);
601		*p = tmp;
602	}
603
604	tmp = *p + *len;
605	snprintf(tmp->name, PATH_MAX, "%s", name);
606	bcopy(us, &tmp->stat, sizeof *us);
607
608	(*len)++;
609	(++tmp)->name[0] = 0;
610
611	return (0);
612}
613