xref: /freebsd/lib/libfetch/common.c (revision a3e8fd0b7f663db7eafff527d5c3ca3bcfa8a537)
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 				return (rlen);
369 			errno = 0;
370 			r = select(conn->sd + 1, &readfds, NULL, NULL, &wait);
371 			if (r == -1) {
372 				if (errno == EINTR && fetchRestartCalls)
373 					continue;
374 				return (-1);
375 			}
376 		}
377 #ifdef WITH_SSL
378 		if (conn->ssl != NULL)
379 			rlen = SSL_read(conn->ssl, buf, len);
380 		else
381 #endif
382 			rlen = read(conn->sd, buf, len);
383 		if (rlen == 0)
384 			break;
385 		if (rlen < 0) {
386 			if (errno == EINTR && fetchRestartCalls)
387 				continue;
388 			return (-1);
389 		}
390 		len -= rlen;
391 		buf += rlen;
392 		total += rlen;
393 	}
394 	return (total);
395 }
396 
397 
398 /*
399  * Read a line of text from a connection w/ timeout
400  */
401 #define MIN_BUF_SIZE 1024
402 
403 int
404 _fetch_getln(conn_t *conn)
405 {
406 	char *tmp;
407 	size_t tmpsize;
408 	char c;
409 	int error;
410 
411 	if (conn->buf == NULL) {
412 		if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
413 			errno = ENOMEM;
414 			return (-1);
415 		}
416 		conn->bufsize = MIN_BUF_SIZE;
417 	}
418 
419 	conn->buf[0] = '\0';
420 	conn->buflen = 0;
421 
422 	do {
423 		error = _fetch_read(conn, &c, 1);
424 		if (error == -1)
425 			return (-1);
426 		else if (error == 0)
427 			break;
428 		conn->buf[conn->buflen++] = c;
429 		if (conn->buflen == conn->bufsize) {
430 			tmp = conn->buf;
431 			tmpsize = conn->bufsize * 2 + 1;
432 			if ((tmp = realloc(tmp, tmpsize)) == NULL) {
433 				errno = ENOMEM;
434 				return (-1);
435 			}
436 			conn->buf = tmp;
437 			conn->bufsize = tmpsize;
438 		}
439 	} while (c != '\n');
440 
441 	conn->buf[conn->buflen] = '\0';
442 	DEBUG(fprintf(stderr, "<<< %s", conn->buf));
443 	return (0);
444 }
445 
446 
447 /*
448  * Write to a connection w/ timeout
449  */
450 ssize_t
451 _fetch_write(conn_t *conn, const char *buf, size_t len)
452 {
453 	struct timeval now, timeout, wait;
454 	fd_set writefds;
455 	ssize_t wlen, total;
456 	int r;
457 
458 	if (fetchTimeout) {
459 		FD_ZERO(&writefds);
460 		gettimeofday(&timeout, NULL);
461 		timeout.tv_sec += fetchTimeout;
462 	}
463 
464 	while (len > 0) {
465 		while (fetchTimeout && !FD_ISSET(conn->sd, &writefds)) {
466 			FD_SET(conn->sd, &writefds);
467 			gettimeofday(&now, NULL);
468 			wait.tv_sec = timeout.tv_sec - now.tv_sec;
469 			wait.tv_usec = timeout.tv_usec - now.tv_usec;
470 			if (wait.tv_usec < 0) {
471 				wait.tv_usec += 1000000;
472 				wait.tv_sec--;
473 			}
474 			if (wait.tv_sec < 0) {
475 				errno = ETIMEDOUT;
476 				return (-1);
477 			}
478 			errno = 0;
479 			r = select(conn->sd + 1, NULL, &writefds, NULL, &wait);
480 			if (r == -1) {
481 				if (errno == EINTR && fetchRestartCalls)
482 					continue;
483 				return (-1);
484 			}
485 		}
486 		errno = 0;
487 #ifdef WITH_SSL
488 		if (conn->ssl != NULL)
489 			wlen = SSL_write(conn->ssl, buf, len);
490 		else
491 #endif
492 			wlen = write(conn->sd, buf, len);
493 		if (wlen == 0)
494 			/* we consider a short write a failure */
495 			return (-1);
496 		if (wlen < 0) {
497 			if (errno == EINTR && fetchRestartCalls)
498 				continue;
499 			return (-1);
500 		}
501 		len -= wlen;
502 		buf += wlen;
503 		total += wlen;
504 	}
505 	return (total);
506 }
507 
508 
509 /*
510  * Write a line of text to a connection w/ timeout
511  */
512 int
513 _fetch_putln(conn_t *conn, const char *str, size_t len)
514 {
515 
516 	DEBUG(fprintf(stderr, ">>> %s\n", str));
517 	if (_fetch_write(conn, str, len) == -1 ||
518 	    _fetch_write(conn, ENDL, sizeof ENDL) == -1)
519 		return (-1);
520 	return (0);
521 }
522 
523 
524 /*
525  * Close connection
526  */
527 int
528 _fetch_close(conn_t *conn)
529 {
530 	int ret;
531 
532 	if (--conn->ref > 0)
533 		return (0);
534 	ret = close(conn->sd);
535 	free(conn);
536 	return (ret);
537 }
538 
539 
540 /*** Directory-related utility functions *************************************/
541 
542 int
543 _fetch_add_entry(struct url_ent **p, int *size, int *len,
544     const char *name, struct url_stat *us)
545 {
546 	struct url_ent *tmp;
547 
548 	if (*p == NULL) {
549 		*size = 0;
550 		*len = 0;
551 	}
552 
553 	if (*len >= *size - 1) {
554 		tmp = realloc(*p, (*size * 2 + 1) * sizeof **p);
555 		if (tmp == NULL) {
556 			errno = ENOMEM;
557 			_fetch_syserr();
558 			return (-1);
559 		}
560 		*size = (*size * 2 + 1);
561 		*p = tmp;
562 	}
563 
564 	tmp = *p + *len;
565 	snprintf(tmp->name, PATH_MAX, "%s", name);
566 	bcopy(us, &tmp->stat, sizeof *us);
567 
568 	(*len)++;
569 	(++tmp)->name[0] = 0;
570 
571 	return (0);
572 }
573