xref: /freebsd/lib/libfetch/fetch.c (revision c11e094d96120a2e0e726ed9705ae0ec08db49b6)
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/errno.h>
34 
35 #include <ctype.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 
40 #include "fetch.h"
41 #include "common.h"
42 
43 auth_t	 fetchAuthMethod;
44 int	 fetchLastErrCode;
45 char	 fetchLastErrString[MAXERRSTRING];
46 int	 fetchTimeout;
47 int	 fetchRestartCalls = 1;
48 int	 fetchDebug;
49 
50 
51 /*** Local data **************************************************************/
52 
53 /*
54  * Error messages for parser errors
55  */
56 #define URL_MALFORMED		1
57 #define URL_BAD_SCHEME		2
58 #define URL_BAD_PORT		3
59 static struct fetcherr _url_errlist[] = {
60 	{ URL_MALFORMED,	FETCH_URL,	"Malformed URL" },
61 	{ URL_BAD_SCHEME,	FETCH_URL,	"Invalid URL scheme" },
62 	{ URL_BAD_PORT,		FETCH_URL,	"Invalid server port" },
63 	{ -1,			FETCH_UNKNOWN,	"Unknown parser error" }
64 };
65 
66 
67 /*** Public API **************************************************************/
68 
69 /*
70  * Select the appropriate protocol for the URL scheme, and return a
71  * read-only stream connected to the document referenced by the URL.
72  * Also fill out the struct url_stat.
73  */
74 FILE *
75 fetchXGet(struct url *URL, struct url_stat *us, const char *flags)
76 {
77 	int direct;
78 
79 	direct = CHECK_FLAG('d');
80 	if (strcasecmp(URL->scheme, SCHEME_FILE) == 0)
81 		return (fetchXGetFile(URL, us, flags));
82 	else if (strcasecmp(URL->scheme, SCHEME_HTTP) == 0)
83 		return (fetchXGetHTTP(URL, us, flags));
84 	else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) {
85 		return (fetchXGetFTP(URL, us, flags));
86 	} else {
87 		_url_seterr(URL_BAD_SCHEME);
88 		return (NULL);
89 	}
90 }
91 
92 /*
93  * Select the appropriate protocol for the URL scheme, and return a
94  * read-only stream connected to the document referenced by the URL.
95  */
96 FILE *
97 fetchGet(struct url *URL, const char *flags)
98 {
99 	return (fetchXGet(URL, NULL, flags));
100 }
101 
102 /*
103  * Select the appropriate protocol for the URL scheme, and return a
104  * write-only stream connected to the document referenced by the URL.
105  */
106 FILE *
107 fetchPut(struct url *URL, const char *flags)
108 {
109 	int direct;
110 
111 	direct = CHECK_FLAG('d');
112 	if (strcasecmp(URL->scheme, SCHEME_FILE) == 0)
113 		return (fetchPutFile(URL, flags));
114 	else if (strcasecmp(URL->scheme, SCHEME_HTTP) == 0)
115 		return (fetchPutHTTP(URL, flags));
116 	else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0) {
117 		return (fetchPutFTP(URL, flags));
118 	} else {
119 		_url_seterr(URL_BAD_SCHEME);
120 		return (NULL);
121 	}
122 }
123 
124 /*
125  * Select the appropriate protocol for the URL scheme, and return the
126  * size of the document referenced by the URL if it exists.
127  */
128 int
129 fetchStat(struct url *URL, struct url_stat *us, const char *flags)
130 {
131 	int direct;
132 
133 	direct = CHECK_FLAG('d');
134 	if (strcasecmp(URL->scheme, SCHEME_FILE) == 0)
135 		return (fetchStatFile(URL, us, flags));
136 	else if (strcasecmp(URL->scheme, SCHEME_HTTP) == 0)
137 		return (fetchStatHTTP(URL, us, flags));
138 	else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0)
139 		return (fetchStatFTP(URL, us, flags));
140 	_url_seterr(URL_BAD_SCHEME);
141 	return (-1);
142 }
143 
144 /*
145  * Select the appropriate protocol for the URL scheme, and return a
146  * list of files in the directory pointed to by the URL.
147  */
148 struct url_ent *
149 fetchList(struct url *URL, const char *flags)
150 {
151 	int direct;
152 
153 	direct = CHECK_FLAG('d');
154 	if (strcasecmp(URL->scheme, SCHEME_FILE) == 0)
155 		return (fetchListFile(URL, flags));
156 	else if (strcasecmp(URL->scheme, SCHEME_HTTP) == 0)
157 		return (fetchListHTTP(URL, flags));
158 	else if (strcasecmp(URL->scheme, SCHEME_FTP) == 0)
159 		return (fetchListFTP(URL, flags));
160 	_url_seterr(URL_BAD_SCHEME);
161 	return (NULL);
162 }
163 
164 /*
165  * Attempt to parse the given URL; if successful, call fetchXGet().
166  */
167 FILE *
168 fetchXGetURL(const char *URL, struct url_stat *us, const char *flags)
169 {
170 	struct url *u;
171 	FILE *f;
172 
173 	if ((u = fetchParseURL(URL)) == NULL)
174 		return (NULL);
175 
176 	f = fetchXGet(u, us, flags);
177 
178 	fetchFreeURL(u);
179 	return (f);
180 }
181 
182 /*
183  * Attempt to parse the given URL; if successful, call fetchGet().
184  */
185 FILE *
186 fetchGetURL(const char *URL, const char *flags)
187 {
188 	return (fetchXGetURL(URL, NULL, flags));
189 }
190 
191 /*
192  * Attempt to parse the given URL; if successful, call fetchPut().
193  */
194 FILE *
195 fetchPutURL(const char *URL, const char *flags)
196 {
197 	struct url *u;
198 	FILE *f;
199 
200 	if ((u = fetchParseURL(URL)) == NULL)
201 		return (NULL);
202 
203 	f = fetchPut(u, flags);
204 
205 	fetchFreeURL(u);
206 	return (f);
207 }
208 
209 /*
210  * Attempt to parse the given URL; if successful, call fetchStat().
211  */
212 int
213 fetchStatURL(const char *URL, struct url_stat *us, const char *flags)
214 {
215 	struct url *u;
216 	int s;
217 
218 	if ((u = fetchParseURL(URL)) == NULL)
219 		return (-1);
220 
221 	s = fetchStat(u, us, flags);
222 
223 	fetchFreeURL(u);
224 	return (s);
225 }
226 
227 /*
228  * Attempt to parse the given URL; if successful, call fetchList().
229  */
230 struct url_ent *
231 fetchListURL(const char *URL, const char *flags)
232 {
233 	struct url *u;
234 	struct url_ent *ue;
235 
236 	if ((u = fetchParseURL(URL)) == NULL)
237 		return (NULL);
238 
239 	ue = fetchList(u, flags);
240 
241 	fetchFreeURL(u);
242 	return (ue);
243 }
244 
245 /*
246  * Make a URL
247  */
248 struct url *
249 fetchMakeURL(const char *scheme, const char *host, int port, const char *doc,
250     const char *user, const char *pwd)
251 {
252 	struct url *u;
253 
254 	if (!scheme || (!host && !doc)) {
255 		_url_seterr(URL_MALFORMED);
256 		return (NULL);
257 	}
258 
259 	if (port < 0 || port > 65535) {
260 		_url_seterr(URL_BAD_PORT);
261 		return (NULL);
262 	}
263 
264 	/* allocate struct url */
265 	if ((u = calloc(1, sizeof *u)) == NULL) {
266 		_fetch_syserr();
267 		return (NULL);
268 	}
269 
270 	if ((u->doc = strdup(doc ? doc : "/")) == NULL) {
271 		_fetch_syserr();
272 		free(u);
273 		return (NULL);
274 	}
275 
276 #define seturl(x) snprintf(u->x, sizeof u->x, "%s", x)
277 	seturl(scheme);
278 	seturl(host);
279 	seturl(user);
280 	seturl(pwd);
281 #undef seturl
282 	u->port = port;
283 
284 	return (u);
285 }
286 
287 /*
288  * Split an URL into components. URL syntax is:
289  * [method:/][/[user[:pwd]@]host[:port]/][document]
290  * This almost, but not quite, RFC1738 URL syntax.
291  */
292 struct url *
293 fetchParseURL(const char *URL)
294 {
295 	char *doc;
296 	const char *p, *q;
297 	struct url *u;
298 	int i;
299 
300 	/* allocate struct url */
301 	if ((u = calloc(1, sizeof *u)) == NULL) {
302 		_fetch_syserr();
303 		return (NULL);
304 	}
305 
306 	/* scheme name */
307 	if ((p = strstr(URL, ":/"))) {
308 		snprintf(u->scheme, URL_SCHEMELEN+1,
309 		    "%.*s", (int)(p - URL), URL);
310 		URL = ++p;
311 		/*
312 		 * Only one slash: no host, leave slash as part of document
313 		 * Two slashes: host follows, strip slashes
314 		 */
315 		if (URL[1] == '/')
316 			URL = (p += 2);
317 	} else {
318 		p = URL;
319 	}
320 	if (!*URL || *URL == '/' || *URL == '.' ||
321 	    (u->scheme[0] == '\0' &&
322 		strchr(URL, '/') == NULL && strchr(URL, ':') == NULL))
323 		goto nohost;
324 
325 	p = strpbrk(URL, "/@");
326 	if (p && *p == '@') {
327 		/* username */
328 		for (q = URL, i = 0; (*q != ':') && (*q != '@'); q++)
329 			if (i < URL_USERLEN)
330 				u->user[i++] = *q;
331 
332 		/* password */
333 		if (*q == ':')
334 			for (q++, i = 0; (*q != ':') && (*q != '@'); q++)
335 				if (i < URL_PWDLEN)
336 					u->pwd[i++] = *q;
337 
338 		p++;
339 	} else {
340 		p = URL;
341 	}
342 
343 	/* hostname */
344 #ifdef INET6
345 	if (*p == '[' && (q = strchr(p + 1, ']')) != NULL &&
346 	    (*++q == '\0' || *q == '/' || *q == ':')) {
347 		if ((i = q - p - 2) > MAXHOSTNAMELEN)
348 			i = MAXHOSTNAMELEN;
349 		strncpy(u->host, ++p, i);
350 		p = q;
351 	} else
352 #endif
353 		for (i = 0; *p && (*p != '/') && (*p != ':'); p++)
354 			if (i < MAXHOSTNAMELEN)
355 				u->host[i++] = *p;
356 
357 	/* port */
358 	if (*p == ':') {
359 		for (q = ++p; *q && (*q != '/'); q++)
360 			if (isdigit(*q))
361 				u->port = u->port * 10 + (*q - '0');
362 			else {
363 				/* invalid port */
364 				_url_seterr(URL_BAD_PORT);
365 				goto ouch;
366 			}
367 		p = q;
368 	}
369 
370 nohost:
371 	/* document */
372 	if (!*p)
373 		p = "/";
374 
375 	if (strcasecmp(u->scheme, SCHEME_HTTP) == 0 ||
376 	    strcasecmp(u->scheme, SCHEME_HTTPS) == 0) {
377 		const char hexnums[] = "0123456789abcdef";
378 
379 		/* percent-escape whitespace. */
380 		if ((doc = malloc(strlen(p) * 3 + 1)) == NULL) {
381 			_fetch_syserr();
382 			goto ouch;
383 		}
384 		u->doc = doc;
385 		while (*p != '\0') {
386 			if (!isspace(*p)) {
387 				*doc++ = *p++;
388 			} else {
389 				*doc++ = '%';
390 				*doc++ = hexnums[((unsigned int)*p) >> 4];
391 				*doc++ = hexnums[((unsigned int)*p) & 0xf];
392 				p++;
393 			}
394 		}
395 		*doc = '\0';
396 	} else if ((u->doc = strdup(p)) == NULL) {
397 		_fetch_syserr();
398 		goto ouch;
399 	}
400 
401 	DEBUG(fprintf(stderr,
402 		  "scheme:   [%s]\n"
403 		  "user:     [%s]\n"
404 		  "password: [%s]\n"
405 		  "host:     [%s]\n"
406 		  "port:     [%d]\n"
407 		  "document: [%s]\n",
408 		  u->scheme, u->user, u->pwd,
409 		  u->host, u->port, u->doc));
410 
411 	return (u);
412 
413 ouch:
414 	free(u);
415 	return (NULL);
416 }
417 
418 /*
419  * Free a URL
420  */
421 void
422 fetchFreeURL(struct url *u)
423 {
424 	free(u->doc);
425 	free(u);
426 }
427