common.c revision 97891 
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 97891 2002-06-05 21:35:35Z 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 * Create a connection for an existing descriptor.
200 */
201conn_t *
202_fetch_reopen(int sd)
203{
204	conn_t *conn;
205
206	/* allocate and fill connection structure */
207	if ((conn = calloc(1, sizeof *conn)) == NULL)
208		return (NULL);
209	conn->sd = sd;
210	return (conn);
211}
212
213
214/*
215 * Establish a TCP connection to the specified port on the specified host.
216 */
217conn_t *
218_fetch_connect(const char *host, int port, int af, int verbose)
219{
220	conn_t *conn;
221	char pbuf[10];
222	struct addrinfo hints, *res, *res0;
223	int sd, err;
224
225	DEBUG(fprintf(stderr, "---> %s:%d\n", host, port));
226
227	if (verbose)
228		_fetch_info("looking up %s", host);
229
230	/* look up host name and set up socket address structure */
231	snprintf(pbuf, sizeof(pbuf), "%d", port);
232	memset(&hints, 0, sizeof(hints));
233	hints.ai_family = af;
234	hints.ai_socktype = SOCK_STREAM;
235	hints.ai_protocol = 0;
236	if ((err = getaddrinfo(host, pbuf, &hints, &res0)) != 0) {
237		_netdb_seterr(err);
238		return (NULL);
239	}
240
241	if (verbose)
242		_fetch_info("connecting to %s:%d", host, port);
243
244	/* try to connect */
245	for (sd = -1, res = res0; res; res = res->ai_next) {
246		if ((sd = socket(res->ai_family, res->ai_socktype,
247			 res->ai_protocol)) == -1)
248			continue;
249		if (connect(sd, res->ai_addr, res->ai_addrlen) != -1)
250			break;
251		close(sd);
252		sd = -1;
253	}
254	freeaddrinfo(res0);
255	if (sd == -1) {
256		_fetch_syserr();
257		return (NULL);
258	}
259
260	if ((conn = _fetch_reopen(sd)) == NULL)
261		close(sd);
262	return (conn);
263}
264
265
266/*
267 * Enable SSL on a connection.
268 */
269int
270_fetch_ssl(conn_t *conn, int verbose)
271{
272
273#ifdef WITH_SSL
274	/* Init the SSL library and context */
275	if (!SSL_library_init()){
276		fprintf(stderr, "SSL library init failed\n");
277		return (-1);
278	}
279
280	SSL_load_error_strings();
281
282	conn->ssl_meth = SSLv23_client_method();
283	conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth);
284
285	conn->ssl = SSL_new(conn->ssl_ctx);
286	if (conn->ssl == NULL){
287		fprintf(stderr, "SSL context creation failed\n");
288		return (-1);
289	}
290	SSL_set_fd(conn->ssl, conn->sd);
291	if (SSL_connect(conn->ssl) == -1){
292		ERR_print_errors_fp(stderr);
293		return (-1);
294	}
295
296	if (verbose) {
297		X509_NAME *name;
298		char *str;
299
300		fprintf(stderr, "SSL connection established using %s\n",
301		    SSL_get_cipher(conn->ssl));
302		conn->ssl_cert = SSL_get_peer_certificate(conn->ssl);
303		name = X509_get_subject_name(conn->ssl_cert);
304		str = X509_NAME_oneline(name, 0, 0);
305		printf("Certificate subject: %s\n", str);
306		free(str);
307		name = X509_get_issuer_name(conn->ssl_cert);
308		str = X509_NAME_oneline(name, 0, 0);
309		printf("Certificate issuer: %s\n", str);
310		free(str);
311	}
312
313	return (0);
314#else
315	(void)conn;
316	(void)verbose;
317	fprintf(stderr, "SSL support disabled\n");
318	return (-1);
319#endif
320}
321
322/*
323 * Read a character from a connection w/ timeout
324 */
325ssize_t
326_fetch_read(conn_t *conn, char *buf, size_t len)
327{
328	struct timeval now, timeout, wait;
329	fd_set readfds;
330	ssize_t rlen, total;
331	int r;
332
333	if (fetchTimeout) {
334		FD_ZERO(&readfds);
335		gettimeofday(&timeout, NULL);
336		timeout.tv_sec += fetchTimeout;
337	}
338
339	total = 0;
340	while (len > 0) {
341		while (fetchTimeout && !FD_ISSET(conn->sd, &readfds)) {
342			FD_SET(conn->sd, &readfds);
343			gettimeofday(&now, NULL);
344			wait.tv_sec = timeout.tv_sec - now.tv_sec;
345			wait.tv_usec = timeout.tv_usec - now.tv_usec;
346			if (wait.tv_usec < 0) {
347				wait.tv_usec += 1000000;
348				wait.tv_sec--;
349			}
350			if (wait.tv_sec < 0)
351				return (rlen);
352			errno = 0;
353			r = select(conn->sd + 1, &readfds, NULL, NULL, &wait);
354			if (r == -1) {
355				if (errno == EINTR && fetchRestartCalls)
356					continue;
357				return (-1);
358			}
359		}
360#ifdef WITH_SSL
361		if (conn->ssl != NULL)
362			rlen = SSL_read(conn->ssl, buf, len);
363		else
364#endif
365			rlen = read(conn->sd, buf, len);
366		if (rlen == 0)
367			break;
368		if (rlen < 0) {
369			if (errno == EINTR && fetchRestartCalls)
370				continue;
371			return (-1);
372		}
373		len -= rlen;
374		buf += rlen;
375		total += rlen;
376	}
377	return (total);
378}
379
380/*
381 * Read a line of text from a connection w/ timeout
382 */
383#define MIN_BUF_SIZE 1024
384
385int
386_fetch_getln(conn_t *conn)
387{
388	char *tmp;
389	size_t tmpsize;
390	char c;
391
392	if (conn->buf == NULL) {
393		if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
394			errno = ENOMEM;
395			return (-1);
396		}
397		conn->bufsize = MIN_BUF_SIZE;
398	}
399
400	conn->buf[0] = '\0';
401	conn->buflen = 0;
402
403	do {
404		if (_fetch_read(conn, &c, 1) == -1)
405			return (-1);
406		conn->buf[conn->buflen++] = c;
407		if (conn->buflen == conn->bufsize) {
408			tmp = conn->buf;
409			tmpsize = conn->bufsize * 2 + 1;
410			if ((tmp = realloc(tmp, tmpsize)) == NULL) {
411				errno = ENOMEM;
412				return (-1);
413			}
414			conn->buf = tmp;
415			conn->bufsize = tmpsize;
416		}
417	} while (c != '\n');
418
419	conn->buf[conn->buflen] = '\0';
420	DEBUG(fprintf(stderr, "<<< %s", conn->buf));
421	return (0);
422}
423
424
425/*
426 * Write to a connection w/ timeout
427 */
428ssize_t
429_fetch_write(conn_t *conn, const char *buf, size_t len)
430{
431	struct timeval now, timeout, wait;
432	fd_set writefds;
433	ssize_t wlen, total;
434	int r;
435
436	if (fetchTimeout) {
437		FD_ZERO(&writefds);
438		gettimeofday(&timeout, NULL);
439		timeout.tv_sec += fetchTimeout;
440	}
441
442	while (len > 0) {
443		while (fetchTimeout && !FD_ISSET(conn->sd, &writefds)) {
444			FD_SET(conn->sd, &writefds);
445			gettimeofday(&now, NULL);
446			wait.tv_sec = timeout.tv_sec - now.tv_sec;
447			wait.tv_usec = timeout.tv_usec - now.tv_usec;
448			if (wait.tv_usec < 0) {
449				wait.tv_usec += 1000000;
450				wait.tv_sec--;
451			}
452			if (wait.tv_sec < 0) {
453				errno = ETIMEDOUT;
454				return (-1);
455			}
456			errno = 0;
457			r = select(conn->sd + 1, NULL, &writefds, NULL, &wait);
458			if (r == -1) {
459				if (errno == EINTR && fetchRestartCalls)
460					continue;
461				return (-1);
462			}
463		}
464		errno = 0;
465#ifdef WITH_SSL
466		if (conn->ssl != NULL)
467			wlen = SSL_write(conn->ssl, buf, len);
468		else
469#endif
470			wlen = write(conn->sd, buf, len);
471		if (wlen == 0)
472			/* we consider a short write a failure */
473			return (-1);
474		if (wlen < 0) {
475			if (errno == EINTR && fetchRestartCalls)
476				continue;
477			return (-1);
478		}
479		len -= wlen;
480		buf += wlen;
481		total += wlen;
482	}
483	return (total);
484}
485
486/*
487 * Write a line of text to a connection w/ timeout
488 */
489int
490_fetch_putln(conn_t *conn, const char *str, size_t len)
491{
492	if (_fetch_write(conn, str, len) == -1 ||
493	    _fetch_write(conn, ENDL, sizeof ENDL) == -1)
494		return (-1);
495	return (0);
496}
497
498
499/*
500 * Close connection
501 */
502int
503_fetch_close(conn_t *conn)
504{
505	int ret;
506
507	ret = close(conn->sd);
508	free(conn);
509	return (ret);
510}
511
512
513/*** Directory-related utility functions *************************************/
514
515int
516_fetch_add_entry(struct url_ent **p, int *size, int *len,
517    const char *name, struct url_stat *us)
518{
519	struct url_ent *tmp;
520
521	if (*p == NULL) {
522		*size = 0;
523		*len = 0;
524	}
525
526	if (*len >= *size - 1) {
527		tmp = realloc(*p, (*size * 2 + 1) * sizeof **p);
528		if (tmp == NULL) {
529			errno = ENOMEM;
530			_fetch_syserr();
531			return (-1);
532		}
533		*size = (*size * 2 + 1);
534		*p = tmp;
535	}
536
537	tmp = *p + *len;
538	snprintf(tmp->name, PATH_MAX, "%s", name);
539	bcopy(us, &tmp->stat, sizeof *us);
540
541	(*len)++;
542	(++tmp)->name[0] = 0;
543
544	return (0);
545}
546