common.c revision 97868 
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 97868 2002-06-05 12:46:36Z 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	/* Init the SSL library and context */
274	if (!SSL_library_init()){
275		fprintf(stderr, "SSL library init failed\n");
276		return (-1);
277	}
278
279	SSL_load_error_strings();
280
281	conn->ssl_meth = SSLv23_client_method();
282	conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth);
283
284	conn->ssl = SSL_new(conn->ssl_ctx);
285	if (conn->ssl == NULL){
286		fprintf(stderr, "SSL context creation failed\n");
287		return (-1);
288	}
289	SSL_set_fd(conn->ssl, conn->sd);
290	if (SSL_connect(conn->ssl) == -1){
291		ERR_print_errors_fp(stderr);
292		return (-1);
293	}
294
295	if (verbose) {
296		X509_NAME *name;
297		char *str;
298
299		fprintf(stderr, "SSL connection established using %s\n",
300		    SSL_get_cipher(conn->ssl));
301		conn->ssl_cert = SSL_get_peer_certificate(conn->ssl);
302		name = X509_get_subject_name(conn->ssl_cert);
303		str = X509_NAME_oneline(name, 0, 0);
304		printf("Certificate subject: %s\n", str);
305		free(str);
306		name = X509_get_issuer_name(conn->ssl_cert);
307		str = X509_NAME_oneline(name, 0, 0);
308		printf("Certificate issuer: %s\n", str);
309		free(str);
310	}
311
312	return (0);
313}
314
315/*
316 * Read a character from a connection w/ timeout
317 */
318ssize_t
319_fetch_read(conn_t *conn, char *buf, size_t len)
320{
321	struct timeval now, timeout, wait;
322	fd_set readfds;
323	ssize_t rlen, total;
324	int r;
325
326	if (fetchTimeout) {
327		FD_ZERO(&readfds);
328		gettimeofday(&timeout, NULL);
329		timeout.tv_sec += fetchTimeout;
330	}
331
332	total = 0;
333	while (len > 0) {
334		while (fetchTimeout && !FD_ISSET(conn->sd, &readfds)) {
335			FD_SET(conn->sd, &readfds);
336			gettimeofday(&now, NULL);
337			wait.tv_sec = timeout.tv_sec - now.tv_sec;
338			wait.tv_usec = timeout.tv_usec - now.tv_usec;
339			if (wait.tv_usec < 0) {
340				wait.tv_usec += 1000000;
341				wait.tv_sec--;
342			}
343			if (wait.tv_sec < 0)
344				return (rlen);
345			errno = 0;
346			r = select(conn->sd + 1, &readfds, NULL, NULL, &wait);
347			if (r == -1) {
348				if (errno == EINTR && fetchRestartCalls)
349					continue;
350				return (-1);
351			}
352		}
353		if (conn->ssl != NULL)
354			rlen = SSL_read(conn->ssl, buf, len);
355		else
356			rlen = read(conn->sd, buf, len);
357		if (rlen == 0)
358			break;
359		if (rlen < 0) {
360			if (errno == EINTR && fetchRestartCalls)
361				continue;
362			return (-1);
363		}
364		len -= rlen;
365		buf += rlen;
366		total += rlen;
367	}
368	return (total);
369}
370
371/*
372 * Read a line of text from a connection w/ timeout
373 */
374#define MIN_BUF_SIZE 1024
375
376int
377_fetch_getln(conn_t *conn)
378{
379	char *tmp;
380	size_t tmpsize;
381	char c;
382
383	if (conn->buf == NULL) {
384		if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
385			errno = ENOMEM;
386			return (-1);
387		}
388		conn->bufsize = MIN_BUF_SIZE;
389	}
390
391	conn->buf[0] = '\0';
392	conn->buflen = 0;
393
394	do {
395		if (_fetch_read(conn, &c, 1) == -1)
396			return (-1);
397		conn->buf[conn->buflen++] = c;
398		if (conn->buflen == conn->bufsize) {
399			tmp = conn->buf;
400			tmpsize = conn->bufsize * 2 + 1;
401			if ((tmp = realloc(tmp, tmpsize)) == NULL) {
402				errno = ENOMEM;
403				return (-1);
404			}
405			conn->buf = tmp;
406			conn->bufsize = tmpsize;
407		}
408	} while (c != '\n');
409
410	conn->buf[conn->buflen] = '\0';
411	DEBUG(fprintf(stderr, "<<< %s", conn->buf));
412	return (0);
413}
414
415
416/*
417 * Write to a connection w/ timeout
418 */
419ssize_t
420_fetch_write(conn_t *conn, const char *buf, size_t len)
421{
422	struct timeval now, timeout, wait;
423	fd_set writefds;
424	ssize_t wlen, total;
425	int r;
426
427	if (fetchTimeout) {
428		FD_ZERO(&writefds);
429		gettimeofday(&timeout, NULL);
430		timeout.tv_sec += fetchTimeout;
431	}
432
433	while (len > 0) {
434		while (fetchTimeout && !FD_ISSET(conn->sd, &writefds)) {
435			FD_SET(conn->sd, &writefds);
436			gettimeofday(&now, NULL);
437			wait.tv_sec = timeout.tv_sec - now.tv_sec;
438			wait.tv_usec = timeout.tv_usec - now.tv_usec;
439			if (wait.tv_usec < 0) {
440				wait.tv_usec += 1000000;
441				wait.tv_sec--;
442			}
443			if (wait.tv_sec < 0) {
444				errno = ETIMEDOUT;
445				return (-1);
446			}
447			errno = 0;
448			r = select(conn->sd + 1, NULL, &writefds, NULL, &wait);
449			if (r == -1) {
450				if (errno == EINTR && fetchRestartCalls)
451					continue;
452				return (-1);
453			}
454		}
455		errno = 0;
456		if (conn->ssl != NULL)
457			wlen = SSL_write(conn->ssl, buf, len);
458		else
459			wlen = write(conn->sd, buf, len);
460		if (wlen == 0)
461			/* we consider a short write a failure */
462			return (-1);
463		if (wlen < 0) {
464			if (errno == EINTR && fetchRestartCalls)
465				continue;
466			return (-1);
467		}
468		len -= wlen;
469		buf += wlen;
470		total += wlen;
471	}
472	return (total);
473}
474
475/*
476 * Write a line of text to a connection w/ timeout
477 */
478int
479_fetch_putln(conn_t *conn, const char *str, size_t len)
480{
481	if (_fetch_write(conn, str, len) == -1 ||
482	    _fetch_write(conn, ENDL, sizeof ENDL) == -1)
483		return (-1);
484	return (0);
485}
486
487
488/*
489 * Close connection
490 */
491int
492_fetch_close(conn_t *conn)
493{
494	int ret;
495
496	ret = close(conn->sd);
497	free(conn);
498	return (ret);
499}
500
501
502/*** Directory-related utility functions *************************************/
503
504int
505_fetch_add_entry(struct url_ent **p, int *size, int *len,
506    const char *name, struct url_stat *us)
507{
508	struct url_ent *tmp;
509
510	if (*p == NULL) {
511		*size = 0;
512		*len = 0;
513	}
514
515	if (*len >= *size - 1) {
516		tmp = realloc(*p, (*size * 2 + 1) * sizeof **p);
517		if (tmp == NULL) {
518			errno = ENOMEM;
519			_fetch_syserr();
520			return (-1);
521		}
522		*size = (*size * 2 + 1);
523		*p = tmp;
524	}
525
526	tmp = *p + *len;
527	snprintf(tmp->name, PATH_MAX, "%s", name);
528	bcopy(us, &tmp->stat, sizeof *us);
529
530	(*len)++;
531	(++tmp)->name[0] = 0;
532
533	return (0);
534}
535