xref: /freebsd/lib/libfetch/common.c (revision 5773cccf19ef7b97e56c1101aa481c43149224da)
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("$FreeBSD$");
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  */
55 static 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 */
64 static const char ENDL[2] = "\r\n";
65 
66 
67 /*** Error-reporting functions ***********************************************/
68 
69 /*
70  * Map error code to string
71  */
72 static 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  */
83 void
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  */
94 void
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;
144 default:
145 		fetchLastErrCode = FETCH_UNKNOWN;
146 	}
147 	snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno));
148 }
149 
150 
151 /*
152  * Emit status message
153  */
154 void
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  */
171 int
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  */
188 int
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  */
202 conn_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  */
219 conn_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  */
231 conn_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  */
285 int
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  */
342 ssize_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 
407 int
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  */
454 ssize_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  */
468 ssize_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  */
543 int
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  */
567 int
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 
582 int
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