1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1998-2016 Dag-Erling Sm��rgrav
5 * Copyright (c) 2013 Michael Gmelin <freebsd@grem.de>
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer
13 *    in this position and unchanged.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. The name of the author may not be used to endorse or promote products
18 *    derived from this software without specific prior written permission
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/param.h>
33#include <sys/socket.h>
34#include <sys/time.h>
35#include <sys/uio.h>
36
37#include <netinet/in.h>
38
39#include <ctype.h>
40#include <errno.h>
41#include <fcntl.h>
42#include <inttypes.h>
43#include <netdb.h>
44#include <paths.h>
45#include <poll.h>
46#include <pwd.h>
47#include <stdarg.h>
48#include <stdlib.h>
49#include <stdio.h>
50#include <string.h>
51#include <unistd.h>
52
53#ifdef WITH_SSL
54#include <openssl/x509v3.h>
55#endif
56
57#include "fetch.h"
58#include "common.h"
59
60
61/*** Local data **************************************************************/
62
63/*
64 * Error messages for resolver errors
65 */
66static struct fetcherr netdb_errlist[] = {
67#ifdef EAI_ADDRFAMILY
68	{ EAI_ADDRFAMILY, FETCH_RESOLV, "Address family for host not supported" },
69#endif
70#ifdef EAI_NODATA
71	{ EAI_NODATA,	FETCH_RESOLV,	"No address for host" },
72#endif
73	{ EAI_AGAIN,	FETCH_TEMP,	"Transient resolver failure" },
74	{ EAI_FAIL,	FETCH_RESOLV,	"Non-recoverable resolver failure" },
75	{ EAI_NONAME,	FETCH_RESOLV,	"Host does not resolve" },
76	{ -1,		FETCH_UNKNOWN,	"Unknown resolver error" }
77};
78
79/*
80 * SOCKS5 error enumerations
81 */
82enum SOCKS5_ERR {
83/* Protocol errors */
84	SOCKS5_ERR_SELECTION,
85	SOCKS5_ERR_READ_METHOD,
86	SOCKS5_ERR_VER5_ONLY,
87	SOCKS5_ERR_NOMETHODS,
88	SOCKS5_ERR_NOTIMPLEMENTED,
89	SOCKS5_ERR_HOSTNAME_SIZE,
90	SOCKS5_ERR_REQUEST,
91	SOCKS5_ERR_REPLY,
92	SOCKS5_ERR_NON_VER5_RESP,
93	SOCKS5_ERR_GENERAL,
94	SOCKS5_ERR_NOT_ALLOWED,
95	SOCKS5_ERR_NET_UNREACHABLE,
96	SOCKS5_ERR_HOST_UNREACHABLE,
97	SOCKS5_ERR_CONN_REFUSED,
98	SOCKS5_ERR_TTL_EXPIRED,
99	SOCKS5_ERR_COM_UNSUPPORTED,
100	SOCKS5_ERR_ADDR_UNSUPPORTED,
101	SOCKS5_ERR_UNSPECIFIED,
102/* Configuration errors */
103	SOCKS5_ERR_BAD_HOST,
104	SOCKS5_ERR_BAD_PROXY_FORMAT,
105	SOCKS5_ERR_BAD_PORT
106};
107
108/*
109 * Error messages for SOCKS5 errors
110 */
111static struct fetcherr socks5_errlist[] = {
112/* SOCKS5 protocol errors */
113	{ SOCKS5_ERR_SELECTION,		FETCH_ABORT,	"SOCKS5: Failed to send selection method" },
114	{ SOCKS5_ERR_READ_METHOD,	FETCH_ABORT,	"SOCKS5: Failed to read method" },
115	{ SOCKS5_ERR_VER5_ONLY,		FETCH_PROTO,	"SOCKS5: Only version 5 is implemented" },
116	{ SOCKS5_ERR_NOMETHODS,		FETCH_PROTO,	"SOCKS5: No acceptable methods" },
117	{ SOCKS5_ERR_NOTIMPLEMENTED,	FETCH_PROTO,	"SOCKS5: Method currently not implemented" },
118	{ SOCKS5_ERR_HOSTNAME_SIZE,	FETCH_PROTO,	"SOCKS5: Hostname size is above 256 bytes" },
119	{ SOCKS5_ERR_REQUEST,		FETCH_PROTO,	"SOCKS5: Failed to request" },
120	{ SOCKS5_ERR_REPLY,		FETCH_PROTO,	"SOCKS5: Failed to receive reply" },
121	{ SOCKS5_ERR_NON_VER5_RESP,	FETCH_PROTO,	"SOCKS5: Server responded with a non-version 5 response" },
122	{ SOCKS5_ERR_GENERAL,		FETCH_ABORT,	"SOCKS5: General server failure" },
123	{ SOCKS5_ERR_NOT_ALLOWED,	FETCH_AUTH,	"SOCKS5: Connection not allowed by ruleset" },
124	{ SOCKS5_ERR_NET_UNREACHABLE,	FETCH_NETWORK,	"SOCKS5: Network unreachable" },
125	{ SOCKS5_ERR_HOST_UNREACHABLE,	FETCH_ABORT,	"SOCKS5: Host unreachable" },
126	{ SOCKS5_ERR_CONN_REFUSED,	FETCH_ABORT,	"SOCKS5: Connection refused" },
127	{ SOCKS5_ERR_TTL_EXPIRED,	FETCH_TIMEOUT,	"SOCKS5: TTL expired" },
128	{ SOCKS5_ERR_COM_UNSUPPORTED,	FETCH_PROTO,	"SOCKS5: Command not supported" },
129	{ SOCKS5_ERR_ADDR_UNSUPPORTED,	FETCH_ABORT,	"SOCKS5: Address type not supported" },
130	{ SOCKS5_ERR_UNSPECIFIED,	FETCH_UNKNOWN,	"SOCKS5: Unspecified error" },
131/* Configuration error */
132	{ SOCKS5_ERR_BAD_HOST,		FETCH_ABORT,	"SOCKS5: Bad proxy host" },
133	{ SOCKS5_ERR_BAD_PROXY_FORMAT,	FETCH_ABORT,	"SOCKS5: Bad proxy format" },
134	{ SOCKS5_ERR_BAD_PORT,		FETCH_ABORT,	"SOCKS5: Bad port" }
135};
136
137/* End-of-Line */
138static const char ENDL[2] = "\r\n";
139
140
141/*** Error-reporting functions ***********************************************/
142
143/*
144 * Map error code to string
145 */
146static struct fetcherr *
147fetch_finderr(struct fetcherr *p, int e)
148{
149	while (p->num != -1 && p->num != e)
150		p++;
151	return (p);
152}
153
154/*
155 * Set error code
156 */
157void
158fetch_seterr(struct fetcherr *p, int e)
159{
160	p = fetch_finderr(p, e);
161	fetchLastErrCode = p->cat;
162	snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string);
163}
164
165/*
166 * Set error code according to errno
167 */
168void
169fetch_syserr(void)
170{
171	switch (errno) {
172	case 0:
173		fetchLastErrCode = FETCH_OK;
174		break;
175	case EPERM:
176	case EACCES:
177	case EROFS:
178	case EAUTH:
179	case ENEEDAUTH:
180		fetchLastErrCode = FETCH_AUTH;
181		break;
182	case ENOENT:
183	case EISDIR: /* XXX */
184		fetchLastErrCode = FETCH_UNAVAIL;
185		break;
186	case ENOMEM:
187		fetchLastErrCode = FETCH_MEMORY;
188		break;
189	case EBUSY:
190	case EAGAIN:
191		fetchLastErrCode = FETCH_TEMP;
192		break;
193	case EEXIST:
194		fetchLastErrCode = FETCH_EXISTS;
195		break;
196	case ENOSPC:
197		fetchLastErrCode = FETCH_FULL;
198		break;
199	case EADDRINUSE:
200	case EADDRNOTAVAIL:
201	case ENETDOWN:
202	case ENETUNREACH:
203	case ENETRESET:
204	case EHOSTUNREACH:
205		fetchLastErrCode = FETCH_NETWORK;
206		break;
207	case ECONNABORTED:
208	case ECONNRESET:
209		fetchLastErrCode = FETCH_ABORT;
210		break;
211	case ETIMEDOUT:
212		fetchLastErrCode = FETCH_TIMEOUT;
213		break;
214	case ECONNREFUSED:
215	case EHOSTDOWN:
216		fetchLastErrCode = FETCH_DOWN;
217		break;
218	default:
219		fetchLastErrCode = FETCH_UNKNOWN;
220	}
221	snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno));
222}
223
224
225/*
226 * Emit status message
227 */
228void
229fetch_info(const char *fmt, ...)
230{
231	va_list ap;
232
233	va_start(ap, fmt);
234	vfprintf(stderr, fmt, ap);
235	va_end(ap);
236	fputc('\n', stderr);
237}
238
239
240/*** Network-related utility functions ***************************************/
241
242/*
243 * Return the default port for a scheme
244 */
245int
246fetch_default_port(const char *scheme)
247{
248	struct servent *se;
249
250	if ((se = getservbyname(scheme, "tcp")) != NULL)
251		return (ntohs(se->s_port));
252	if (strcmp(scheme, SCHEME_FTP) == 0)
253		return (FTP_DEFAULT_PORT);
254	if (strcmp(scheme, SCHEME_HTTP) == 0)
255		return (HTTP_DEFAULT_PORT);
256	return (0);
257}
258
259/*
260 * Return the default proxy port for a scheme
261 */
262int
263fetch_default_proxy_port(const char *scheme)
264{
265	if (strcmp(scheme, SCHEME_FTP) == 0)
266		return (FTP_DEFAULT_PROXY_PORT);
267	if (strcmp(scheme, SCHEME_HTTP) == 0)
268		return (HTTP_DEFAULT_PROXY_PORT);
269	return (0);
270}
271
272
273/*
274 * Create a connection for an existing descriptor.
275 */
276conn_t *
277fetch_reopen(int sd)
278{
279	conn_t *conn;
280	int opt = 1;
281
282	/* allocate and fill connection structure */
283	if ((conn = calloc(1, sizeof(*conn))) == NULL)
284		return (NULL);
285	fcntl(sd, F_SETFD, FD_CLOEXEC);
286	setsockopt(sd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof opt);
287	conn->sd = sd;
288	++conn->ref;
289	return (conn);
290}
291
292
293/*
294 * Bump a connection's reference count.
295 */
296conn_t *
297fetch_ref(conn_t *conn)
298{
299
300	++conn->ref;
301	return (conn);
302}
303
304
305/*
306 * Resolve an address
307 */
308struct addrinfo *
309fetch_resolve(const char *addr, int port, int af)
310{
311	char hbuf[256], sbuf[8];
312	struct addrinfo hints, *res;
313	const char *hb, *he, *sep;
314	const char *host, *service;
315	int err, len;
316
317	/* first, check for a bracketed IPv6 address */
318	if (*addr == '[') {
319		hb = addr + 1;
320		if ((sep = strchr(hb, ']')) == NULL) {
321			errno = EINVAL;
322			goto syserr;
323		}
324		he = sep++;
325	} else {
326		hb = addr;
327		sep = strchrnul(hb, ':');
328		he = sep;
329	}
330
331	/* see if we need to copy the host name */
332	if (*he != '\0') {
333		len = snprintf(hbuf, sizeof(hbuf),
334		    "%.*s", (int)(he - hb), hb);
335		if (len < 0)
336			goto syserr;
337		if (len >= (int)sizeof(hbuf)) {
338			errno = ENAMETOOLONG;
339			goto syserr;
340		}
341		host = hbuf;
342	} else {
343		host = hb;
344	}
345
346	/* was it followed by a service name? */
347	if (*sep == '\0' && port != 0) {
348		if (port < 1 || port > 65535) {
349			errno = EINVAL;
350			goto syserr;
351		}
352		if (snprintf(sbuf, sizeof(sbuf), "%d", port) < 0)
353			goto syserr;
354		service = sbuf;
355	} else if (*sep != '\0') {
356		service = sep + 1;
357	} else {
358		service = NULL;
359	}
360
361	/* resolve */
362	memset(&hints, 0, sizeof(hints));
363	hints.ai_family = af;
364	hints.ai_socktype = SOCK_STREAM;
365	hints.ai_flags = AI_ADDRCONFIG;
366	if ((err = getaddrinfo(host, service, &hints, &res)) != 0) {
367		netdb_seterr(err);
368		return (NULL);
369	}
370	return (res);
371syserr:
372	fetch_syserr();
373	return (NULL);
374}
375
376
377/*
378 * Bind a socket to a specific local address
379 */
380int
381fetch_bind(int sd, int af, const char *addr)
382{
383	struct addrinfo *cliai, *ai;
384	int err;
385
386	if ((cliai = fetch_resolve(addr, 0, af)) == NULL)
387		return (-1);
388	for (ai = cliai; ai != NULL; ai = ai->ai_next)
389		if ((err = bind(sd, ai->ai_addr, ai->ai_addrlen)) == 0)
390			break;
391	if (err != 0)
392		fetch_syserr();
393	freeaddrinfo(cliai);
394	return (err == 0 ? 0 : -1);
395}
396
397
398/*
399 * SOCKS5 connection initiation, based on RFC 1928
400 * Default DNS resolution over SOCKS5
401 */
402int
403fetch_socks5_init(conn_t *conn, const char *host, int port, int verbose)
404{
405	/*
406	 * Size is based on largest packet prefix (4 bytes) +
407	 * Largest FQDN (256) + one byte size (1) +
408	 * Port (2)
409	 */
410	unsigned char buf[BUFF_SIZE];
411	unsigned char *ptr;
412	int ret = 1;
413
414	if (verbose)
415		fetch_info("Initializing SOCKS5 connection: %s:%d", host, port);
416
417	/* Connection initialization */
418	ptr = buf;
419	*ptr++ = SOCKS_VERSION_5;
420	*ptr++ = SOCKS_CONNECTION;
421	*ptr++ = SOCKS_RSV;
422
423	if (fetch_write(conn, buf, 3) != 3) {
424		ret = SOCKS5_ERR_SELECTION;
425		goto fail;
426	}
427
428	/* Verify response from SOCKS5 server */
429	if (fetch_read(conn, buf, 2) != 2) {
430		ret = SOCKS5_ERR_READ_METHOD;
431		goto fail;
432	}
433
434	ptr = buf;
435	if (ptr[0] != SOCKS_VERSION_5) {
436		ret = SOCKS5_ERR_VER5_ONLY;
437		goto fail;
438	}
439	if (ptr[1] == SOCKS_NOMETHODS) {
440		ret = SOCKS5_ERR_NOMETHODS;
441		goto fail;
442	}
443	else if (ptr[1] != SOCKS5_NOTIMPLEMENTED) {
444		ret = SOCKS5_ERR_NOTIMPLEMENTED;
445		goto fail;
446	}
447
448	/* Send Request */
449	*ptr++ = SOCKS_VERSION_5;
450	*ptr++ = SOCKS_CONNECTION;
451	*ptr++ = SOCKS_RSV;
452	/* Encode all targets as a hostname to avoid DNS leaks */
453	*ptr++ = SOCKS_ATYP_DOMAINNAME;
454	if (strlen(host) > FQDN_SIZE) {
455		ret = SOCKS5_ERR_HOSTNAME_SIZE;
456		goto fail;
457	}
458	*ptr++ = strlen(host);
459	memcpy(ptr, host, strlen(host));
460	ptr = ptr + strlen(host);
461
462	port = htons(port);
463	*ptr++ = port & 0x00ff;
464	*ptr++ = (port & 0xff00) >> 8;
465
466	if (fetch_write(conn, buf, ptr - buf) != ptr - buf) {
467		ret = SOCKS5_ERR_REQUEST;
468		goto fail;
469	}
470
471	/* BND.ADDR is variable length, read the largest on non-blocking socket */
472	if (!fetch_read(conn, buf, BUFF_SIZE)) {
473		ret = SOCKS5_ERR_REPLY;
474		goto fail;
475	}
476
477	ptr = buf;
478	if (*ptr++ != SOCKS_VERSION_5) {
479		ret = SOCKS5_ERR_NON_VER5_RESP;
480		goto fail;
481	}
482
483	switch(*ptr++) {
484	case SOCKS_SUCCESS:
485		break;
486	case SOCKS_GENERAL_FAILURE:
487		ret = SOCKS5_ERR_GENERAL;
488		goto fail;
489	case SOCKS_CONNECTION_NOT_ALLOWED:
490		ret = SOCKS5_ERR_NOT_ALLOWED;
491		goto fail;
492	case SOCKS_NETWORK_UNREACHABLE:
493		ret = SOCKS5_ERR_NET_UNREACHABLE;
494		goto fail;
495	case SOCKS_HOST_UNREACHABLE:
496		ret = SOCKS5_ERR_HOST_UNREACHABLE;
497		goto fail;
498	case SOCKS_CONNECTION_REFUSED:
499		ret = SOCKS5_ERR_CONN_REFUSED;
500		goto fail;
501	case SOCKS_TTL_EXPIRED:
502		ret = SOCKS5_ERR_TTL_EXPIRED;
503		goto fail;
504	case SOCKS_COMMAND_NOT_SUPPORTED:
505		ret = SOCKS5_ERR_COM_UNSUPPORTED;
506		goto fail;
507	case SOCKS_ADDRESS_NOT_SUPPORTED:
508		ret = SOCKS5_ERR_ADDR_UNSUPPORTED;
509		goto fail;
510	default:
511		ret = SOCKS5_ERR_UNSPECIFIED;
512		goto fail;
513	}
514
515	return (ret);
516
517fail:
518	socks5_seterr(ret);
519	return (0);
520}
521
522/*
523 * Perform SOCKS5 initialization
524 */
525int
526fetch_socks5_getenv(char **host, int *port)
527{
528	char *socks5env, *endptr, *ext;
529	const char *portDelim;
530	size_t slen;
531
532	portDelim = ":";
533	if ((socks5env = getenv("SOCKS5_PROXY")) == NULL || *socks5env == '\0') {
534		*host = NULL;
535		*port = -1;
536		return (-1);
537	}
538
539	/*
540	 * IPv6 addresses begin and end in brackets.  Set the port delimiter
541	 * accordingly and search for it so we can do appropriate validation.
542	 */
543	if (socks5env[0] == '[')
544		portDelim = "]:";
545
546	slen = strlen(socks5env);
547	ext = strstr(socks5env, portDelim);
548	if (socks5env[0] == '[') {
549		if (socks5env[slen - 1] == ']') {
550			*host = strndup(socks5env, slen);
551		} else if (ext != NULL) {
552			*host = strndup(socks5env, ext - socks5env + 1);
553		} else {
554			socks5_seterr(SOCKS5_ERR_BAD_PROXY_FORMAT);
555			return (0);
556		}
557	} else {
558		*host = strndup(socks5env, ext - socks5env);
559	}
560
561	if (*host == NULL) {
562		fprintf(stderr, "Failure to allocate memory, exiting.\n");
563		return (-1);
564	}
565	if (ext == NULL) {
566		*port = 1080; /* Default port as defined in RFC1928 */
567	} else {
568		ext += strlen(portDelim);
569		errno = 0;
570		*port = strtoimax(ext, (char **)&endptr, 10);
571		if (*endptr != '\0' || errno != 0 || *port < 0 ||
572		    *port > 65535) {
573			free(*host);
574			*host = NULL;
575			socks5_seterr(SOCKS5_ERR_BAD_PORT);
576			return (0);
577		}
578	}
579
580	return (2);
581}
582
583
584/*
585 * Establish a TCP connection to the specified port on the specified host.
586 */
587conn_t *
588fetch_connect(const char *host, int port, int af, int verbose)
589{
590	struct addrinfo *cais = NULL, *sais = NULL, *cai, *sai;
591	const char *bindaddr;
592	conn_t *conn = NULL;
593	int err = 0, sd = -1;
594	char *sockshost;
595	int socksport;
596
597	DEBUGF("---> %s:%d\n", host, port);
598
599	/*
600	 * Check if SOCKS5_PROXY env variable is set.  fetch_socks5_getenv
601	 * will either set sockshost = NULL or allocate memory in all cases.
602	 */
603	sockshost = NULL;
604	if (!fetch_socks5_getenv(&sockshost, &socksport))
605		goto fail;
606
607	/* Not using SOCKS5 proxy */
608	if (sockshost == NULL) {
609		/* resolve server address */
610		if (verbose)
611			fetch_info("resolving server address: %s:%d", host,
612			    port);
613		if ((sais = fetch_resolve(host, port, af)) == NULL)
614			goto fail;
615
616		/* resolve client address */
617		bindaddr = getenv("FETCH_BIND_ADDRESS");
618		if (bindaddr != NULL && *bindaddr != '\0') {
619			if (verbose)
620				fetch_info("resolving client address: %s",
621				    bindaddr);
622			if ((cais = fetch_resolve(bindaddr, 0, af)) == NULL)
623				goto fail;
624		}
625	} else {
626		/* resolve socks5 proxy address */
627		if (verbose)
628			fetch_info("resolving SOCKS5 server address: %s:%d",
629			    sockshost, socksport);
630		if ((sais = fetch_resolve(sockshost, socksport, af)) == NULL) {
631			socks5_seterr(SOCKS5_ERR_BAD_HOST);
632			goto fail;
633		}
634	}
635
636	/* try each server address in turn */
637	for (err = 0, sai = sais; sai != NULL; sai = sai->ai_next) {
638		/* open socket */
639		if ((sd = socket(sai->ai_family, SOCK_STREAM, 0)) < 0)
640			goto syserr;
641		/* attempt to bind to client address */
642		for (err = 0, cai = cais; cai != NULL; cai = cai->ai_next) {
643			if (cai->ai_family != sai->ai_family)
644				continue;
645			if ((err = bind(sd, cai->ai_addr, cai->ai_addrlen)) == 0)
646				break;
647		}
648		if (err != 0) {
649			if (verbose)
650				fetch_info("failed to bind to %s", bindaddr);
651			goto syserr;
652		}
653		/* attempt to connect to server address */
654		if ((err = connect(sd, sai->ai_addr, sai->ai_addrlen)) == 0)
655			break;
656		/* clean up before next attempt */
657		close(sd);
658		sd = -1;
659	}
660	if (err != 0) {
661		if (verbose && sockshost == NULL) {
662			fetch_info("failed to connect to %s:%d", host, port);
663			goto syserr;
664		} else if (sockshost != NULL) {
665			if (verbose)
666				fetch_info(
667				    "failed to connect to SOCKS5 server %s:%d",
668				    sockshost, socksport);
669			socks5_seterr(SOCKS5_ERR_CONN_REFUSED);
670			goto fail;
671		}
672		goto syserr;
673	}
674
675	if ((conn = fetch_reopen(sd)) == NULL)
676		goto syserr;
677
678	if (sockshost)
679		if (!fetch_socks5_init(conn, host, port, verbose))
680			goto fail;
681	free(sockshost);
682	if (cais != NULL)
683		freeaddrinfo(cais);
684	if (sais != NULL)
685		freeaddrinfo(sais);
686	return (conn);
687syserr:
688	fetch_syserr();
689fail:
690	free(sockshost);
691	/* Fully close if it was opened; otherwise just don't leak the fd. */
692	if (conn != NULL)
693		fetch_close(conn);
694	else if (sd >= 0)
695		close(sd);
696	if (cais != NULL)
697		freeaddrinfo(cais);
698	if (sais != NULL)
699		freeaddrinfo(sais);
700	return (NULL);
701}
702
703#ifdef WITH_SSL
704/*
705 * Convert characters A-Z to lowercase (intentionally avoid any locale
706 * specific conversions).
707 */
708static char
709fetch_ssl_tolower(char in)
710{
711	if (in >= 'A' && in <= 'Z')
712		return (in + 32);
713	else
714		return (in);
715}
716
717/*
718 * isalpha implementation that intentionally avoids any locale specific
719 * conversions.
720 */
721static int
722fetch_ssl_isalpha(char in)
723{
724	return ((in >= 'A' && in <= 'Z') || (in >= 'a' && in <= 'z'));
725}
726
727/*
728 * Check if passed hostnames a and b are equal.
729 */
730static int
731fetch_ssl_hname_equal(const char *a, size_t alen, const char *b,
732    size_t blen)
733{
734	size_t i;
735
736	if (alen != blen)
737		return (0);
738	for (i = 0; i < alen; ++i) {
739		if (fetch_ssl_tolower(a[i]) != fetch_ssl_tolower(b[i]))
740			return (0);
741	}
742	return (1);
743}
744
745/*
746 * Check if domain label is traditional, meaning that only A-Z, a-z, 0-9
747 * and '-' (hyphen) are allowed. Hyphens have to be surrounded by alpha-
748 * numeric characters. Double hyphens (like they're found in IDN a-labels
749 * 'xn--') are not allowed. Empty labels are invalid.
750 */
751static int
752fetch_ssl_is_trad_domain_label(const char *l, size_t len, int wcok)
753{
754	size_t i;
755
756	if (!len || l[0] == '-' || l[len-1] == '-')
757		return (0);
758	for (i = 0; i < len; ++i) {
759		if (!isdigit(l[i]) &&
760		    !fetch_ssl_isalpha(l[i]) &&
761		    !(l[i] == '*' && wcok) &&
762		    !(l[i] == '-' && l[i - 1] != '-'))
763			return (0);
764	}
765	return (1);
766}
767
768/*
769 * Check if host name consists only of numbers. This might indicate an IP
770 * address, which is not a good idea for CN wildcard comparison.
771 */
772static int
773fetch_ssl_hname_is_only_numbers(const char *hostname, size_t len)
774{
775	size_t i;
776
777	for (i = 0; i < len; ++i) {
778		if (!((hostname[i] >= '0' && hostname[i] <= '9') ||
779		    hostname[i] == '.'))
780			return (0);
781	}
782	return (1);
783}
784
785/*
786 * Check if the host name h passed matches the pattern passed in m which
787 * is usually part of subjectAltName or CN of a certificate presented to
788 * the client. This includes wildcard matching. The algorithm is based on
789 * RFC6125, sections 6.4.3 and 7.2, which clarifies RFC2818 and RFC3280.
790 */
791static int
792fetch_ssl_hname_match(const char *h, size_t hlen, const char *m,
793    size_t mlen)
794{
795	int delta, hdotidx, mdot1idx, wcidx;
796	const char *hdot, *mdot1, *mdot2;
797	const char *wc; /* wildcard */
798
799	if (!(h && *h && m && *m))
800		return (0);
801	if ((wc = strnstr(m, "*", mlen)) == NULL)
802		return (fetch_ssl_hname_equal(h, hlen, m, mlen));
803	wcidx = wc - m;
804	/* hostname should not be just dots and numbers */
805	if (fetch_ssl_hname_is_only_numbers(h, hlen))
806		return (0);
807	/* only one wildcard allowed in pattern */
808	if (strnstr(wc + 1, "*", mlen - wcidx - 1) != NULL)
809		return (0);
810	/*
811	 * there must be at least two more domain labels and
812	 * wildcard has to be in the leftmost label (RFC6125)
813	 */
814	mdot1 = strnstr(m, ".", mlen);
815	if (mdot1 == NULL || mdot1 < wc || (mlen - (mdot1 - m)) < 4)
816		return (0);
817	mdot1idx = mdot1 - m;
818	mdot2 = strnstr(mdot1 + 1, ".", mlen - mdot1idx - 1);
819	if (mdot2 == NULL || (mlen - (mdot2 - m)) < 2)
820		return (0);
821	/* hostname must contain a dot and not be the 1st char */
822	hdot = strnstr(h, ".", hlen);
823	if (hdot == NULL || hdot == h)
824		return (0);
825	hdotidx = hdot - h;
826	/*
827	 * host part of hostname must be at least as long as
828	 * pattern it's supposed to match
829	 */
830	if (hdotidx < mdot1idx)
831		return (0);
832	/*
833	 * don't allow wildcards in non-traditional domain names
834	 * (IDN, A-label, U-label...)
835	 */
836	if (!fetch_ssl_is_trad_domain_label(h, hdotidx, 0) ||
837	    !fetch_ssl_is_trad_domain_label(m, mdot1idx, 1))
838		return (0);
839	/* match domain part (part after first dot) */
840	if (!fetch_ssl_hname_equal(hdot, hlen - hdotidx, mdot1,
841	    mlen - mdot1idx))
842		return (0);
843	/* match part left of wildcard */
844	if (!fetch_ssl_hname_equal(h, wcidx, m, wcidx))
845		return (0);
846	/* match part right of wildcard */
847	delta = mdot1idx - wcidx - 1;
848	if (!fetch_ssl_hname_equal(hdot - delta, delta,
849	    mdot1 - delta, delta))
850		return (0);
851	/* all tests succeeded, it's a match */
852	return (1);
853}
854
855/*
856 * Get numeric host address info - returns NULL if host was not an IP
857 * address. The caller is responsible for deallocation using
858 * freeaddrinfo(3).
859 */
860static struct addrinfo *
861fetch_ssl_get_numeric_addrinfo(const char *hostname, size_t len)
862{
863	struct addrinfo hints, *res;
864	char *host;
865
866	host = (char *)malloc(len + 1);
867	memcpy(host, hostname, len);
868	host[len] = '\0';
869	memset(&hints, 0, sizeof(hints));
870	hints.ai_family = PF_UNSPEC;
871	hints.ai_socktype = SOCK_STREAM;
872	hints.ai_protocol = 0;
873	hints.ai_flags = AI_NUMERICHOST;
874	/* port is not relevant for this purpose */
875	if (getaddrinfo(host, "443", &hints, &res) != 0)
876		res = NULL;
877	free(host);
878	return res;
879}
880
881/*
882 * Compare ip address in addrinfo with address passes.
883 */
884static int
885fetch_ssl_ipaddr_match_bin(const struct addrinfo *lhost, const char *rhost,
886    size_t rhostlen)
887{
888	const void *left;
889
890	if (lhost->ai_family == AF_INET && rhostlen == 4) {
891		left = (void *)&((struct sockaddr_in*)(void *)
892		    lhost->ai_addr)->sin_addr.s_addr;
893#ifdef INET6
894	} else if (lhost->ai_family == AF_INET6 && rhostlen == 16) {
895		left = (void *)&((struct sockaddr_in6 *)(void *)
896		    lhost->ai_addr)->sin6_addr;
897#endif
898	} else
899		return (0);
900	return (!memcmp(left, (const void *)rhost, rhostlen) ? 1 : 0);
901}
902
903/*
904 * Compare ip address in addrinfo with host passed. If host is not an IP
905 * address, comparison will fail.
906 */
907static int
908fetch_ssl_ipaddr_match(const struct addrinfo *laddr, const char *r,
909    size_t rlen)
910{
911	struct addrinfo *raddr;
912	int ret;
913	char *rip;
914
915	ret = 0;
916	if ((raddr = fetch_ssl_get_numeric_addrinfo(r, rlen)) == NULL)
917		return 0; /* not a numeric host */
918
919	if (laddr->ai_family == raddr->ai_family) {
920		if (laddr->ai_family == AF_INET) {
921			rip = (char *)&((struct sockaddr_in *)(void *)
922			    raddr->ai_addr)->sin_addr.s_addr;
923			ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 4);
924#ifdef INET6
925		} else if (laddr->ai_family == AF_INET6) {
926			rip = (char *)&((struct sockaddr_in6 *)(void *)
927			    raddr->ai_addr)->sin6_addr;
928			ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 16);
929#endif
930		}
931
932	}
933	freeaddrinfo(raddr);
934	return (ret);
935}
936
937/*
938 * Verify server certificate by subjectAltName.
939 */
940static int
941fetch_ssl_verify_altname(STACK_OF(GENERAL_NAME) *altnames,
942    const char *host, struct addrinfo *ip)
943{
944	const GENERAL_NAME *name;
945	size_t nslen;
946	int i;
947	const char *ns;
948
949	for (i = 0; i < sk_GENERAL_NAME_num(altnames); ++i) {
950		name = sk_GENERAL_NAME_value(altnames, i);
951		ns = (const char *)ASN1_STRING_get0_data(name->d.ia5);
952		nslen = (size_t)ASN1_STRING_length(name->d.ia5);
953
954		if (name->type == GEN_DNS && ip == NULL &&
955		    fetch_ssl_hname_match(host, strlen(host), ns, nslen))
956			return (1);
957		else if (name->type == GEN_IPADD && ip != NULL &&
958		    fetch_ssl_ipaddr_match_bin(ip, ns, nslen))
959			return (1);
960	}
961	return (0);
962}
963
964/*
965 * Verify server certificate by CN.
966 */
967static int
968fetch_ssl_verify_cn(X509_NAME *subject, const char *host,
969    struct addrinfo *ip)
970{
971	ASN1_STRING *namedata;
972	X509_NAME_ENTRY *nameentry;
973	int cnlen, lastpos, loc, ret;
974	unsigned char *cn;
975
976	ret = 0;
977	lastpos = -1;
978	loc = -1;
979	cn = NULL;
980	/* get most specific CN (last entry in list) and compare */
981	while ((lastpos = X509_NAME_get_index_by_NID(subject,
982	    NID_commonName, lastpos)) != -1)
983		loc = lastpos;
984
985	if (loc > -1) {
986		nameentry = X509_NAME_get_entry(subject, loc);
987		namedata = X509_NAME_ENTRY_get_data(nameentry);
988		cnlen = ASN1_STRING_to_UTF8(&cn, namedata);
989		if (ip == NULL &&
990		    fetch_ssl_hname_match(host, strlen(host), cn, cnlen))
991			ret = 1;
992		else if (ip != NULL && fetch_ssl_ipaddr_match(ip, cn, cnlen))
993			ret = 1;
994		OPENSSL_free(cn);
995	}
996	return (ret);
997}
998
999/*
1000 * Verify that server certificate subjectAltName/CN matches
1001 * hostname. First check, if there are alternative subject names. If yes,
1002 * those have to match. Only if those don't exist it falls back to
1003 * checking the subject's CN.
1004 */
1005static int
1006fetch_ssl_verify_hname(X509 *cert, const char *host)
1007{
1008	struct addrinfo *ip;
1009	STACK_OF(GENERAL_NAME) *altnames;
1010	X509_NAME *subject;
1011	int ret;
1012
1013	ret = 0;
1014	ip = fetch_ssl_get_numeric_addrinfo(host, strlen(host));
1015	altnames = X509_get_ext_d2i(cert, NID_subject_alt_name,
1016	    NULL, NULL);
1017
1018	if (altnames != NULL) {
1019		ret = fetch_ssl_verify_altname(altnames, host, ip);
1020	} else {
1021		subject = X509_get_subject_name(cert);
1022		if (subject != NULL)
1023			ret = fetch_ssl_verify_cn(subject, host, ip);
1024	}
1025
1026	if (ip != NULL)
1027		freeaddrinfo(ip);
1028	if (altnames != NULL)
1029		GENERAL_NAMES_free(altnames);
1030	return (ret);
1031}
1032
1033/*
1034 * Configure transport security layer based on environment.
1035 */
1036static void
1037fetch_ssl_setup_transport_layer(SSL_CTX *ctx, int verbose)
1038{
1039	long ssl_ctx_options;
1040
1041	ssl_ctx_options = SSL_OP_ALL | SSL_OP_NO_SSLv3 | SSL_OP_NO_TICKET;
1042	if (getenv("SSL_NO_TLS1") != NULL)
1043		ssl_ctx_options |= SSL_OP_NO_TLSv1;
1044	if (getenv("SSL_NO_TLS1_1") != NULL)
1045		ssl_ctx_options |= SSL_OP_NO_TLSv1_1;
1046	if (getenv("SSL_NO_TLS1_2") != NULL)
1047		ssl_ctx_options |= SSL_OP_NO_TLSv1_2;
1048	if (verbose)
1049		fetch_info("SSL options: %lx", ssl_ctx_options);
1050	SSL_CTX_set_options(ctx, ssl_ctx_options);
1051}
1052
1053
1054/*
1055 * Configure peer verification based on environment.
1056 */
1057static int
1058fetch_ssl_setup_peer_verification(SSL_CTX *ctx, int verbose)
1059{
1060	X509_LOOKUP *crl_lookup;
1061	X509_STORE *crl_store;
1062	const char *ca_cert_file, *ca_cert_path, *crl_file;
1063
1064	if (getenv("SSL_NO_VERIFY_PEER") == NULL) {
1065		ca_cert_file = getenv("SSL_CA_CERT_FILE");
1066		ca_cert_path = getenv("SSL_CA_CERT_PATH");
1067		if (verbose) {
1068			fetch_info("Peer verification enabled");
1069			if (ca_cert_file != NULL)
1070				fetch_info("Using CA cert file: %s",
1071				    ca_cert_file);
1072			if (ca_cert_path != NULL)
1073				fetch_info("Using CA cert path: %s",
1074				    ca_cert_path);
1075			if (ca_cert_file == NULL && ca_cert_path == NULL)
1076				fetch_info("Using OpenSSL default "
1077				    "CA cert file and path");
1078		}
1079		SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER,
1080		    fetch_ssl_cb_verify_crt);
1081		if (ca_cert_file != NULL || ca_cert_path != NULL)
1082			SSL_CTX_load_verify_locations(ctx, ca_cert_file,
1083			    ca_cert_path);
1084		else
1085			SSL_CTX_set_default_verify_paths(ctx);
1086		if ((crl_file = getenv("SSL_CRL_FILE")) != NULL) {
1087			if (verbose)
1088				fetch_info("Using CRL file: %s", crl_file);
1089			crl_store = SSL_CTX_get_cert_store(ctx);
1090			crl_lookup = X509_STORE_add_lookup(crl_store,
1091			    X509_LOOKUP_file());
1092			if (crl_lookup == NULL ||
1093			    !X509_load_crl_file(crl_lookup, crl_file,
1094				X509_FILETYPE_PEM)) {
1095				fprintf(stderr,
1096				    "Could not load CRL file %s\n",
1097				    crl_file);
1098				return (0);
1099			}
1100			X509_STORE_set_flags(crl_store,
1101			    X509_V_FLAG_CRL_CHECK |
1102			    X509_V_FLAG_CRL_CHECK_ALL);
1103		}
1104	}
1105	return (1);
1106}
1107
1108/*
1109 * Configure client certificate based on environment.
1110 */
1111static int
1112fetch_ssl_setup_client_certificate(SSL_CTX *ctx, int verbose)
1113{
1114	const char *client_cert_file, *client_key_file;
1115
1116	if ((client_cert_file = getenv("SSL_CLIENT_CERT_FILE")) != NULL) {
1117		client_key_file = getenv("SSL_CLIENT_KEY_FILE") != NULL ?
1118		    getenv("SSL_CLIENT_KEY_FILE") : client_cert_file;
1119		if (verbose) {
1120			fetch_info("Using client cert file: %s",
1121			    client_cert_file);
1122			fetch_info("Using client key file: %s",
1123			    client_key_file);
1124		}
1125		if (SSL_CTX_use_certificate_chain_file(ctx,
1126			client_cert_file) != 1) {
1127			fprintf(stderr,
1128			    "Could not load client certificate %s\n",
1129			    client_cert_file);
1130			return (0);
1131		}
1132		if (SSL_CTX_use_PrivateKey_file(ctx, client_key_file,
1133			SSL_FILETYPE_PEM) != 1) {
1134			fprintf(stderr,
1135			    "Could not load client key %s\n",
1136			    client_key_file);
1137			return (0);
1138		}
1139	}
1140	return (1);
1141}
1142
1143/*
1144 * Callback for SSL certificate verification, this is called on server
1145 * cert verification. It takes no decision, but informs the user in case
1146 * verification failed.
1147 */
1148int
1149fetch_ssl_cb_verify_crt(int verified, X509_STORE_CTX *ctx)
1150{
1151	X509 *crt;
1152	X509_NAME *name;
1153	char *str;
1154
1155	str = NULL;
1156	if (!verified) {
1157		if ((crt = X509_STORE_CTX_get_current_cert(ctx)) != NULL &&
1158		    (name = X509_get_subject_name(crt)) != NULL)
1159			str = X509_NAME_oneline(name, 0, 0);
1160		fprintf(stderr, "Certificate verification failed for %s\n",
1161		    str != NULL ? str : "no relevant certificate");
1162		OPENSSL_free(str);
1163	}
1164	return (verified);
1165}
1166
1167#endif
1168
1169/*
1170 * Enable SSL on a connection.
1171 */
1172int
1173fetch_ssl(conn_t *conn, const struct url *URL, int verbose)
1174{
1175#ifdef WITH_SSL
1176	int ret, ssl_err;
1177	X509_NAME *name;
1178	char *str;
1179
1180	conn->ssl_meth = SSLv23_client_method();
1181	conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth);
1182	SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY);
1183
1184	fetch_ssl_setup_transport_layer(conn->ssl_ctx, verbose);
1185	if (!fetch_ssl_setup_peer_verification(conn->ssl_ctx, verbose))
1186		return (-1);
1187	if (!fetch_ssl_setup_client_certificate(conn->ssl_ctx, verbose))
1188		return (-1);
1189
1190	conn->ssl = SSL_new(conn->ssl_ctx);
1191	if (conn->ssl == NULL) {
1192		fprintf(stderr, "SSL context creation failed\n");
1193		return (-1);
1194	}
1195	SSL_set_fd(conn->ssl, conn->sd);
1196
1197#if !defined(OPENSSL_NO_TLSEXT)
1198	if (!SSL_set_tlsext_host_name(conn->ssl,
1199	    __DECONST(struct url *, URL)->host)) {
1200		fprintf(stderr,
1201		    "TLS server name indication extension failed for host %s\n",
1202		    URL->host);
1203		return (-1);
1204	}
1205#endif
1206	while ((ret = SSL_connect(conn->ssl)) == -1) {
1207		ssl_err = SSL_get_error(conn->ssl, ret);
1208		if (ssl_err != SSL_ERROR_WANT_READ &&
1209		    ssl_err != SSL_ERROR_WANT_WRITE) {
1210			ERR_print_errors_fp(stderr);
1211			return (-1);
1212		}
1213	}
1214	conn->ssl_cert = SSL_get_peer_certificate(conn->ssl);
1215
1216	if (conn->ssl_cert == NULL) {
1217		fprintf(stderr, "No server SSL certificate\n");
1218		return (-1);
1219	}
1220
1221	if (getenv("SSL_NO_VERIFY_HOSTNAME") == NULL) {
1222		if (verbose)
1223			fetch_info("Verify hostname");
1224		if (!fetch_ssl_verify_hname(conn->ssl_cert, URL->host)) {
1225			fprintf(stderr,
1226			    "SSL certificate subject doesn't match host %s\n",
1227			    URL->host);
1228			return (-1);
1229		}
1230	}
1231
1232	if (verbose) {
1233		fetch_info("%s connection established using %s",
1234		    SSL_get_version(conn->ssl), SSL_get_cipher(conn->ssl));
1235		name = X509_get_subject_name(conn->ssl_cert);
1236		str = X509_NAME_oneline(name, 0, 0);
1237		fetch_info("Certificate subject: %s", str);
1238		OPENSSL_free(str);
1239		name = X509_get_issuer_name(conn->ssl_cert);
1240		str = X509_NAME_oneline(name, 0, 0);
1241		fetch_info("Certificate issuer: %s", str);
1242		OPENSSL_free(str);
1243	}
1244
1245	return (0);
1246#else
1247	(void)conn;
1248	(void)verbose;
1249	(void)URL;
1250	fprintf(stderr, "SSL support disabled\n");
1251	return (-1);
1252#endif
1253}
1254
1255#define FETCH_READ_WAIT		-2
1256#define FETCH_READ_ERROR	-1
1257#define FETCH_READ_DONE		 0
1258
1259#ifdef WITH_SSL
1260static ssize_t
1261fetch_ssl_read(SSL *ssl, char *buf, size_t len)
1262{
1263	ssize_t rlen;
1264	int ssl_err;
1265
1266	rlen = SSL_read(ssl, buf, len);
1267	if (rlen < 0) {
1268		ssl_err = SSL_get_error(ssl, rlen);
1269		if (ssl_err == SSL_ERROR_WANT_READ ||
1270		    ssl_err == SSL_ERROR_WANT_WRITE) {
1271			return (FETCH_READ_WAIT);
1272		} else {
1273			ERR_print_errors_fp(stderr);
1274			return (FETCH_READ_ERROR);
1275		}
1276	}
1277	return (rlen);
1278}
1279#endif
1280
1281static ssize_t
1282fetch_socket_read(int sd, char *buf, size_t len)
1283{
1284	ssize_t rlen;
1285
1286	rlen = read(sd, buf, len);
1287	if (rlen < 0) {
1288		if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls))
1289			return (FETCH_READ_WAIT);
1290		else
1291			return (FETCH_READ_ERROR);
1292	}
1293	return (rlen);
1294}
1295
1296/*
1297 * Read a character from a connection w/ timeout
1298 */
1299ssize_t
1300fetch_read(conn_t *conn, char *buf, size_t len)
1301{
1302	struct timeval now, timeout, delta;
1303	struct pollfd pfd;
1304	ssize_t rlen;
1305	int deltams;
1306
1307	if (fetchTimeout > 0) {
1308		gettimeofday(&timeout, NULL);
1309		timeout.tv_sec += fetchTimeout;
1310	}
1311
1312	deltams = INFTIM;
1313	memset(&pfd, 0, sizeof pfd);
1314	pfd.fd = conn->sd;
1315	pfd.events = POLLIN | POLLERR;
1316
1317	for (;;) {
1318		/*
1319		 * The socket is non-blocking.  Instead of the canonical
1320		 * poll() -> read(), we do the following:
1321		 *
1322		 * 1) call read() or SSL_read().
1323		 * 2) if we received some data, return it.
1324		 * 3) if an error occurred, return -1.
1325		 * 4) if read() or SSL_read() signaled EOF, return.
1326		 * 5) if we did not receive any data but we're not at EOF,
1327		 *    call poll().
1328		 *
1329		 * In the SSL case, this is necessary because if we
1330		 * receive a close notification, we have to call
1331		 * SSL_read() one additional time after we've read
1332		 * everything we received.
1333		 *
1334		 * In the non-SSL case, it may improve performance (very
1335		 * slightly) when reading small amounts of data.
1336		 */
1337#ifdef WITH_SSL
1338		if (conn->ssl != NULL)
1339			rlen = fetch_ssl_read(conn->ssl, buf, len);
1340		else
1341#endif
1342			rlen = fetch_socket_read(conn->sd, buf, len);
1343		if (rlen >= 0) {
1344			break;
1345		} else if (rlen == FETCH_READ_ERROR) {
1346			fetch_syserr();
1347			return (-1);
1348		}
1349		// assert(rlen == FETCH_READ_WAIT);
1350		if (fetchTimeout > 0) {
1351			gettimeofday(&now, NULL);
1352			if (!timercmp(&timeout, &now, >)) {
1353				errno = ETIMEDOUT;
1354				fetch_syserr();
1355				return (-1);
1356			}
1357			timersub(&timeout, &now, &delta);
1358			deltams = delta.tv_sec * 1000 +
1359			    delta.tv_usec / 1000;
1360		}
1361		errno = 0;
1362		pfd.revents = 0;
1363		if (poll(&pfd, 1, deltams) < 0) {
1364			if (errno == EINTR && fetchRestartCalls)
1365				continue;
1366			fetch_syserr();
1367			return (-1);
1368		}
1369	}
1370	return (rlen);
1371}
1372
1373
1374/*
1375 * Read a line of text from a connection w/ timeout
1376 */
1377#define MIN_BUF_SIZE 1024
1378
1379int
1380fetch_getln(conn_t *conn)
1381{
1382	char *tmp;
1383	size_t tmpsize;
1384	ssize_t len;
1385	char c;
1386
1387	if (conn->buf == NULL) {
1388		if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
1389			errno = ENOMEM;
1390			return (-1);
1391		}
1392		conn->bufsize = MIN_BUF_SIZE;
1393	}
1394
1395	conn->buf[0] = '\0';
1396	conn->buflen = 0;
1397
1398	do {
1399		len = fetch_read(conn, &c, 1);
1400		if (len == -1)
1401			return (-1);
1402		if (len == 0)
1403			break;
1404		conn->buf[conn->buflen++] = c;
1405		if (conn->buflen == conn->bufsize) {
1406			tmp = conn->buf;
1407			tmpsize = conn->bufsize * 2 + 1;
1408			if ((tmp = realloc(tmp, tmpsize)) == NULL) {
1409				errno = ENOMEM;
1410				return (-1);
1411			}
1412			conn->buf = tmp;
1413			conn->bufsize = tmpsize;
1414		}
1415	} while (c != '\n');
1416
1417	conn->buf[conn->buflen] = '\0';
1418	DEBUGF("<<< %s", conn->buf);
1419	return (0);
1420}
1421
1422
1423/*
1424 * Write to a connection w/ timeout
1425 */
1426ssize_t
1427fetch_write(conn_t *conn, const char *buf, size_t len)
1428{
1429	struct iovec iov;
1430
1431	iov.iov_base = __DECONST(char *, buf);
1432	iov.iov_len = len;
1433	return fetch_writev(conn, &iov, 1);
1434}
1435
1436/*
1437 * Write a vector to a connection w/ timeout
1438 * Note: can modify the iovec.
1439 */
1440ssize_t
1441fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt)
1442{
1443	struct timeval now, timeout, delta;
1444	struct pollfd pfd;
1445	ssize_t wlen, total;
1446	int deltams;
1447
1448	memset(&pfd, 0, sizeof pfd);
1449	if (fetchTimeout) {
1450		pfd.fd = conn->sd;
1451		pfd.events = POLLOUT | POLLERR;
1452		gettimeofday(&timeout, NULL);
1453		timeout.tv_sec += fetchTimeout;
1454	}
1455
1456	total = 0;
1457	while (iovcnt > 0) {
1458		while (fetchTimeout && pfd.revents == 0) {
1459			gettimeofday(&now, NULL);
1460			if (!timercmp(&timeout, &now, >)) {
1461				errno = ETIMEDOUT;
1462				fetch_syserr();
1463				return (-1);
1464			}
1465			timersub(&timeout, &now, &delta);
1466			deltams = delta.tv_sec * 1000 +
1467			    delta.tv_usec / 1000;
1468			errno = 0;
1469			pfd.revents = 0;
1470			if (poll(&pfd, 1, deltams) < 0) {
1471				/* POSIX compliance */
1472				if (errno == EAGAIN)
1473					continue;
1474				if (errno == EINTR && fetchRestartCalls)
1475					continue;
1476				return (-1);
1477			}
1478		}
1479		errno = 0;
1480#ifdef WITH_SSL
1481		if (conn->ssl != NULL)
1482			wlen = SSL_write(conn->ssl,
1483			    iov->iov_base, iov->iov_len);
1484		else
1485#endif
1486			wlen = writev(conn->sd, iov, iovcnt);
1487		if (wlen == 0) {
1488			/* we consider a short write a failure */
1489			/* XXX perhaps we shouldn't in the SSL case */
1490			errno = EPIPE;
1491			fetch_syserr();
1492			return (-1);
1493		}
1494		if (wlen < 0) {
1495			if (errno == EINTR && fetchRestartCalls)
1496				continue;
1497			return (-1);
1498		}
1499		total += wlen;
1500		while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) {
1501			wlen -= iov->iov_len;
1502			iov++;
1503			iovcnt--;
1504		}
1505		if (iovcnt > 0) {
1506			iov->iov_len -= wlen;
1507			iov->iov_base = __DECONST(char *, iov->iov_base) + wlen;
1508		}
1509	}
1510	return (total);
1511}
1512
1513
1514/*
1515 * Write a line of text to a connection w/ timeout
1516 */
1517int
1518fetch_putln(conn_t *conn, const char *str, size_t len)
1519{
1520	struct iovec iov[2];
1521	int ret;
1522
1523	DEBUGF(">>> %s\n", str);
1524	iov[0].iov_base = __DECONST(char *, str);
1525	iov[0].iov_len = len;
1526	iov[1].iov_base = __DECONST(char *, ENDL);
1527	iov[1].iov_len = sizeof(ENDL);
1528	if (len == 0)
1529		ret = fetch_writev(conn, &iov[1], 1);
1530	else
1531		ret = fetch_writev(conn, iov, 2);
1532	if (ret == -1)
1533		return (-1);
1534	return (0);
1535}
1536
1537
1538/*
1539 * Close connection
1540 */
1541int
1542fetch_close(conn_t *conn)
1543{
1544	int ret;
1545
1546	if (--conn->ref > 0)
1547		return (0);
1548#ifdef WITH_SSL
1549	if (conn->ssl) {
1550		SSL_shutdown(conn->ssl);
1551		SSL_set_connect_state(conn->ssl);
1552		SSL_free(conn->ssl);
1553		conn->ssl = NULL;
1554	}
1555	if (conn->ssl_ctx) {
1556		SSL_CTX_free(conn->ssl_ctx);
1557		conn->ssl_ctx = NULL;
1558	}
1559	if (conn->ssl_cert) {
1560		X509_free(conn->ssl_cert);
1561		conn->ssl_cert = NULL;
1562	}
1563#endif
1564	ret = close(conn->sd);
1565	free(conn->buf);
1566	free(conn);
1567	return (ret);
1568}
1569
1570
1571/*** Directory-related utility functions *************************************/
1572
1573int
1574fetch_add_entry(struct url_ent **p, int *size, int *len,
1575    const char *name, struct url_stat *us)
1576{
1577	struct url_ent *tmp;
1578
1579	if (*p == NULL) {
1580		*size = 0;
1581		*len = 0;
1582	}
1583
1584	if (*len >= *size - 1) {
1585		tmp = reallocarray(*p, *size * 2 + 1, sizeof(**p));
1586		if (tmp == NULL) {
1587			errno = ENOMEM;
1588			fetch_syserr();
1589			return (-1);
1590		}
1591		*size = (*size * 2 + 1);
1592		*p = tmp;
1593	}
1594
1595	tmp = *p + *len;
1596	snprintf(tmp->name, PATH_MAX, "%s", name);
1597	memcpy(&tmp->stat, us, sizeof(*us));
1598
1599	(*len)++;
1600	(++tmp)->name[0] = 0;
1601
1602	return (0);
1603}
1604
1605
1606/*** Authentication-related utility functions ********************************/
1607
1608static const char *
1609fetch_read_word(FILE *f)
1610{
1611	static char word[1024];
1612
1613	if (fscanf(f, " %1023s ", word) != 1)
1614		return (NULL);
1615	return (word);
1616}
1617
1618static int
1619fetch_netrc_open(void)
1620{
1621	struct passwd *pwd;
1622	char fn[PATH_MAX];
1623	const char *p;
1624	int fd, serrno;
1625
1626	if ((p = getenv("NETRC")) != NULL) {
1627		DEBUGF("NETRC=%s\n", p);
1628		if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) {
1629			fetch_info("$NETRC specifies a file name "
1630			    "longer than PATH_MAX");
1631			return (-1);
1632		}
1633	} else {
1634		if ((p = getenv("HOME")) == NULL) {
1635			if ((pwd = getpwuid(getuid())) == NULL ||
1636			    (p = pwd->pw_dir) == NULL)
1637				return (-1);
1638		}
1639		if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn))
1640			return (-1);
1641	}
1642
1643	if ((fd = open(fn, O_RDONLY)) < 0) {
1644		serrno = errno;
1645		DEBUGF("%s: %s\n", fn, strerror(serrno));
1646		errno = serrno;
1647	}
1648	return (fd);
1649}
1650
1651/*
1652 * Get authentication data for a URL from .netrc
1653 */
1654int
1655fetch_netrc_auth(struct url *url)
1656{
1657	const char *word;
1658	int serrno;
1659	FILE *f;
1660
1661	if (url->netrcfd < 0)
1662		url->netrcfd = fetch_netrc_open();
1663	if (url->netrcfd < 0)
1664		return (-1);
1665	if ((f = fdopen(url->netrcfd, "r")) == NULL) {
1666		serrno = errno;
1667		DEBUGF("fdopen(netrcfd): %s", strerror(errno));
1668		close(url->netrcfd);
1669		url->netrcfd = -1;
1670		errno = serrno;
1671		return (-1);
1672	}
1673	rewind(f);
1674	DEBUGF("searching netrc for %s\n", url->host);
1675	while ((word = fetch_read_word(f)) != NULL) {
1676		if (strcmp(word, "default") == 0) {
1677			DEBUGF("using default netrc settings\n");
1678			break;
1679		}
1680		if (strcmp(word, "machine") == 0 &&
1681		    (word = fetch_read_word(f)) != NULL &&
1682		    strcasecmp(word, url->host) == 0) {
1683			DEBUGF("using netrc settings for %s\n", word);
1684			break;
1685		}
1686	}
1687	if (word == NULL)
1688		goto ferr;
1689	while ((word = fetch_read_word(f)) != NULL) {
1690		if (strcmp(word, "login") == 0) {
1691			if ((word = fetch_read_word(f)) == NULL)
1692				goto ferr;
1693			if (snprintf(url->user, sizeof(url->user),
1694				"%s", word) > (int)sizeof(url->user)) {
1695				fetch_info("login name in .netrc is too long");
1696				url->user[0] = '\0';
1697			}
1698		} else if (strcmp(word, "password") == 0) {
1699			if ((word = fetch_read_word(f)) == NULL)
1700				goto ferr;
1701			if (snprintf(url->pwd, sizeof(url->pwd),
1702				"%s", word) > (int)sizeof(url->pwd)) {
1703				fetch_info("password in .netrc is too long");
1704				url->pwd[0] = '\0';
1705			}
1706		} else if (strcmp(word, "account") == 0) {
1707			if ((word = fetch_read_word(f)) == NULL)
1708				goto ferr;
1709			/* XXX not supported! */
1710		} else {
1711			break;
1712		}
1713	}
1714	fclose(f);
1715	url->netrcfd = -1;
1716	return (0);
1717ferr:
1718	serrno = errno;
1719	fclose(f);
1720	url->netrcfd = -1;
1721	errno = serrno;
1722	return (-1);
1723}
1724
1725/*
1726 * The no_proxy environment variable specifies a set of domains for
1727 * which the proxy should not be consulted; the contents is a comma-,
1728 * or space-separated list of domain names.  A single asterisk will
1729 * override all proxy variables and no transactions will be proxied
1730 * (for compatibility with lynx and curl, see the discussion at
1731 * <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>).
1732 */
1733int
1734fetch_no_proxy_match(const char *host)
1735{
1736	const char *no_proxy, *p, *q;
1737	size_t h_len, d_len;
1738
1739	if ((no_proxy = getenv("NO_PROXY")) == NULL &&
1740	    (no_proxy = getenv("no_proxy")) == NULL)
1741		return (0);
1742
1743	/* asterisk matches any hostname */
1744	if (strcmp(no_proxy, "*") == 0)
1745		return (1);
1746
1747	h_len = strlen(host);
1748	p = no_proxy;
1749	do {
1750		/* position p at the beginning of a domain suffix */
1751		while (*p == ',' || isspace((unsigned char)*p))
1752			p++;
1753
1754		/* position q at the first separator character */
1755		for (q = p; *q; ++q)
1756			if (*q == ',' || isspace((unsigned char)*q))
1757				break;
1758
1759		d_len = q - p;
1760		if (d_len > 0 && h_len >= d_len &&
1761		    strncasecmp(host + h_len - d_len,
1762			p, d_len) == 0) {
1763			/* domain name matches */
1764			return (1);
1765		}
1766
1767		p = q + 1;
1768	} while (*q);
1769
1770	return (0);
1771}
1772