phttpget.c revision 148925 
1/*-
2 * Copyright 2005 Colin Percival
3 * All rights reserved
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted providing 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 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
18 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
23 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24 * POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/usr.sbin/portsnap/phttpget/phttpget.c 148925 2005-08-10 13:45:00Z cperciva $");
29
30#include <sys/types.h>
31#include <sys/time.h>
32#include <sys/socket.h>
33
34#include <ctype.h>
35#include <err.h>
36#include <errno.h>
37#include <fcntl.h>
38#include <limits.h>
39#include <netdb.h>
40#include <stdio.h>
41#include <stdlib.h>
42#include <string.h>
43#include <sysexits.h>
44#include <unistd.h>
45
46static const char *	env_HTTP_PROXY;
47static const char *	env_HTTP_USER_AGENT;
48static const char *	proxyport;
49
50static struct timeval	timo = { 15, 0};
51
52static void
53usage(void)
54{
55
56	fprintf(stderr, "usage: phttpget server [file ...]\n");
57	exit(EX_USAGE);
58}
59
60static void
61readenv(void)
62{
63	char * p;
64
65	env_HTTP_PROXY = getenv("HTTP_PROXY");
66	if (env_HTTP_PROXY) {
67		if (strncmp(env_HTTP_PROXY, "http://", 7) == 0)
68			env_HTTP_PROXY += 7;
69		p = strchr(env_HTTP_PROXY, '/');
70		if (p != NULL)
71			*p = 0;
72		p = strchr(env_HTTP_PROXY, ':');
73		if (p != NULL) {
74			*p = 0;
75			proxyport = p + 1;
76		} else
77			proxyport = "3128";
78	}
79
80	env_HTTP_USER_AGENT = getenv("HTTP_USER_AGENT");
81	if (env_HTTP_USER_AGENT == NULL)
82		env_HTTP_USER_AGENT = "phttpget/0.1";
83}
84
85static int
86makerequest(char ** buf, char * path, char * server, int connclose)
87{
88	int buflen;
89
90	buflen = asprintf(buf,
91	    "GET %s%s/%s HTTP/1.1\r\n"
92	    "Host: %s\r\n"
93	    "User-Agent: %s\r\n"
94	    "%s"
95	    "\r\n",
96	    env_HTTP_PROXY ? "http://" : "",
97	    env_HTTP_PROXY ? server : "",
98	    path, server, env_HTTP_USER_AGENT,
99	    connclose ? "Connection: Close\r\n" : "");
100	if (buflen == -1)
101		err(1, "asprintf");
102	return(buflen);
103}
104
105static int
106readln(int sd, char * resbuf, int * resbuflen, int * resbufpos)
107{
108	ssize_t len;
109
110	while (strnstr(resbuf + *resbufpos, "\r\n",
111	    *resbuflen - *resbufpos) == NULL) {
112		/* Move buffered data to the start of the buffer */
113		if (*resbufpos != 0) {
114			memmove(resbuf, resbuf + *resbufpos,
115			    *resbuflen - *resbufpos);
116			*resbuflen -= *resbufpos;
117			*resbufpos = 0;
118		}
119
120		/* If the buffer is full, complain */
121		if (*resbuflen == BUFSIZ)
122			return -1;
123
124		/* Read more data into the buffer */
125		len = recv(sd, resbuf + *resbuflen, BUFSIZ - *resbuflen, 0);
126		if ((len == -1) && (errno != EINTR))
127			return -1;
128
129		if (len != -1)
130			*resbuflen += len;
131	}
132
133	return 0;
134}
135
136static int
137copybytes(int sd, int fd, off_t copylen, char * resbuf, int * resbuflen,
138    int * resbufpos)
139{
140	ssize_t len;
141
142	while (copylen) {
143		/* Write data from resbuf to fd */
144		len = *resbuflen - *resbufpos;
145		if (copylen < len)
146			len = copylen;
147		if (len > 0) {
148			if (fd != -1)
149				len = write(fd, resbuf + *resbufpos, len);
150			if (len == -1)
151				err(1, "write");
152			*resbufpos += len;
153			copylen -= len;
154			continue;
155		}
156
157		/* Read more data into buffer */
158		len = recv(sd, resbuf, BUFSIZ, 0);
159		if (len == -1) {
160			if (errno == EINTR)
161				continue;
162			return -1;
163		} else if (len == 0) {
164			return -2;
165		} else {
166			*resbuflen = len;
167			*resbufpos = 0;
168		}
169	}
170
171	return 0;
172}
173
174int
175main(int argc, char *argv[])
176{
177	struct addrinfo hints;	/* Hints to getaddrinfo */
178	struct addrinfo *res;	/* Pointer to server address being used */
179	struct addrinfo *res0;	/* Pointer to server addresses */
180	char * resbuf = NULL;	/* Response buffer */
181	int resbufpos = 0;	/* Response buffer position */
182	int resbuflen = 0;	/* Response buffer length */
183	char * eolp;		/* Pointer to "\r\n" within resbuf */
184	char * hln;		/* Pointer within header line */
185	char * servername;	/* Name of server */
186	char * fname = NULL;	/* Name of downloaded file */
187	char * reqbuf = NULL;	/* Request buffer */
188	int reqbufpos = 0;	/* Request buffer position */
189	int reqbuflen = 0;	/* Request buffer length */
190	ssize_t len;		/* Length sent or received */
191	int nreq = 0;		/* Number of next request to send */
192	int nres = 0;		/* Number of next reply to receive */
193	int pipelined = 0;	/* != 0 if connection in pipelined mode. */
194	int sd = -1;		/* Socket descriptor */
195	int sdflags = 0;	/* Flags on the socket sd */
196	int fd = -1;		/* Descriptor for download target file */
197	int error;		/* Error code */
198	int statuscode;		/* HTTP Status code */
199	off_t contentlength;	/* Value from Content-Length header */
200	int chunked;		/* != if transfer-encoding is chunked */
201	off_t clen;		/* Chunk length */
202	int firstreq = 0;	/* # of first request for this connection */
203
204	/* Check that the arguments are sensible */
205	if (argc < 2)
206		usage();
207
208	/* Read important environment variables */
209	readenv();
210
211	/* Get server name and adjust arg[cv] to point at file names */
212	servername = argv[1];
213	argv += 2;
214	argc -= 2;
215
216	/* Allocate response buffer */
217	resbuf = malloc(BUFSIZ);
218	if (resbuf == NULL)
219		err(1, "malloc");
220
221	/* Look up server */
222	memset(&hints, 0, sizeof(hints));
223	hints.ai_family = PF_UNSPEC;
224	hints.ai_socktype = SOCK_STREAM;
225	error = getaddrinfo(env_HTTP_PROXY ? env_HTTP_PROXY : servername,
226	    env_HTTP_PROXY ? proxyport : "http", &hints, &res0);
227	if (error)
228		errx(1, "%s: host = %s, port = %s",
229		    env_HTTP_PROXY ? env_HTTP_PROXY : servername,
230		    env_HTTP_PROXY ? proxyport : "http",
231		    gai_strerror(error));
232	if (res0 == NULL)
233		errx(1, "could not look up %s", servername);
234	res = res0;
235
236	/* Do the fetching */
237	while (nres < argc) {
238		/* Make sure we have a connected socket */
239		for (; sd == -1; res = res->ai_next) {
240			/* No addresses left to try :-( */
241			if (res == NULL)
242				errx(1, "Could not connect to %s", servername);
243
244			/* Create a socket... */
245			sd = socket(res->ai_family, res->ai_socktype,
246			    res->ai_protocol);
247			if (sd == -1)
248				continue;
249
250			/* ... set 15-second timeouts ... */
251			setsockopt(sd, SOL_SOCKET, SO_SNDTIMEO,
252			    (void *)&timo, (socklen_t)sizeof(timo));
253			setsockopt(sd, SOL_SOCKET, SO_RCVTIMEO,
254			    (void *)&timo, (socklen_t)sizeof(timo));
255
256			/* ... and connect to the server. */
257			if(connect(sd, res->ai_addr, res->ai_addrlen)) {
258				close(sd);
259				sd = -1;
260				continue;
261			}
262
263			firstreq = nres;
264		}
265
266		/*
267		 * If in pipelined HTTP mode, put socket into non-blocking
268		 * mode, since we're probably going to want to try to send
269		 * several HTTP requests.
270		 */
271		if (pipelined) {
272			sdflags = fcntl(sd, F_GETFL);
273			if (fcntl(sd, F_SETFL, sdflags | O_NONBLOCK) == -1)
274				err(1, "fcntl");
275		}
276
277		/* Construct requests and/or send them without blocking */
278		while ((nreq < argc) && ((reqbuf == NULL) || pipelined)) {
279			/* If not in the middle of a request, make one */
280			if (reqbuf == NULL) {
281				reqbuflen = makerequest(&reqbuf, argv[nreq],
282				    servername, (nreq == argc - 1));
283				reqbufpos = 0;
284			}
285
286			/* If in pipelined mode, try to send the request */
287			if (pipelined) {
288				while (reqbufpos < reqbuflen) {
289					len = send(sd, reqbuf + reqbufpos,
290					    reqbuflen - reqbufpos, 0);
291					if (len == -1)
292						break;
293					reqbufpos += len;
294				}
295				if (reqbufpos < reqbuflen) {
296					if (errno != EAGAIN)
297						goto conndied;
298					break;
299				} else {
300					free(reqbuf);
301					reqbuf = NULL;
302					nreq++;
303				}
304			}
305		}
306
307		/* Put connection back into blocking mode */
308		if (pipelined) {
309			if (fcntl(sd, F_SETFL, sdflags) == -1)
310				err(1, "fcntl");
311		}
312
313		/* Do we need to blocking-send a request? */
314		if (nres == nreq) {
315			while (reqbufpos < reqbuflen) {
316				len = send(sd, reqbuf + reqbufpos,
317				    reqbuflen - reqbufpos, 0);
318				if (len == -1)
319					goto conndied;
320				reqbufpos += len;
321			}
322			free(reqbuf);
323			reqbuf = NULL;
324			nreq++;
325		}
326
327		/* Scan through the response processing headers. */
328		statuscode = 0;
329		contentlength = -1;
330		chunked = 0;
331		do {
332			/* Get a header line */
333			error = readln(sd, resbuf, &resbuflen, &resbufpos);
334			if (error)
335				goto conndied;
336			hln = resbuf + resbufpos;
337			eolp = strnstr(hln, "\r\n", resbuflen - resbufpos);
338			resbufpos = (eolp - resbuf) + 2;
339			*eolp = '\0';
340
341			/* Make sure it doesn't contain a NUL character */
342			if (strchr(hln, '\0') != eolp)
343				goto conndied;
344
345			if (statuscode == 0) {
346				/* The first line MUST be HTTP/1.x xxx ... */
347				if ((strncmp(hln, "HTTP/1.", 7) != 0) ||
348				    ! isdigit(hln[7]))
349					goto conndied;
350
351				/*
352				 * If the minor version number isn't zero,
353				 * then we can assume that pipelining our
354				 * requests is OK -- as long as we don't
355				 * see a "Connection: close" line later
356				 * and we either have a Content-Length or
357				 * Transfer-Encoding: chunked header to
358				 * tell us the length.
359				 */
360				if (hln[7] != '0')
361					pipelined = 1;
362
363				/* Skip over the minor version number */
364				hln = strchr(hln + 7, ' ');
365				if (hln == NULL)
366					goto conndied;
367				else
368					hln++;
369
370				/* Read the status code */
371				while (isdigit(*hln)) {
372					statuscode = statuscode * 10 +
373					    *hln - '0';
374					hln++;
375				}
376
377				if (statuscode < 100 || statuscode > 599)
378					goto conndied;
379
380				/* Ignore the rest of the line */
381				continue;
382			}
383
384			/* Check for "Connection: close" header */
385			if (strncmp(hln, "Connection:", 11) == 0) {
386				hln += 11;
387				if (strstr(hln, "close") != NULL)
388					pipelined = 0;
389
390				/* Next header... */
391				continue;
392			}
393
394			/* Check for "Content-Length:" header */
395			if (strncmp(hln, "Content-Length:", 15) == 0) {
396				hln += 15;
397				contentlength = 0;
398
399				/* Find the start of the length */
400				while (!isdigit(*hln) && (*hln != '\0'))
401					hln++;
402
403				/* Compute the length */
404				while (isdigit(*hln)) {
405					if (contentlength >= OFF_MAX / 10) {
406						/* Nasty people... */
407						goto conndied;
408					}
409					contentlength = contentlength * 10 +
410					    *hln - '0';
411					hln++;
412				}
413
414				/* Next header... */
415				continue;
416			}
417
418			/* Check for "Transfer-Encoding: chunked" header */
419			if (strncmp(hln, "Transfer-Encoding:", 18) == 0) {
420				hln += 18;
421				if (strstr(hln, "chunked") != NULL)
422					chunked = 1;
423
424				/* Next header... */
425				continue;
426			}
427
428			/* We blithely ignore any other header lines */
429
430			/* No more header lines */
431			if (strlen(hln) == 0) {
432				/*
433				 * If the status code was 1xx, then there will
434				 * be a real header later.  Servers may emit
435				 * 1xx header blocks at will, but since we
436				 * don't expect one, we should just ignore it.
437				 */
438				if (100 <= statuscode && statuscode <= 199) {
439					statuscode = 0;
440					continue;
441				}
442
443				/* End of header; message body follows */
444				break;
445			}
446		} while (1);
447
448		/* No message body for 204 or 304 */
449		if (statuscode == 204 || statuscode == 304) {
450			nres++;
451			continue;
452		}
453
454		/*
455		 * There should be a message body coming, but we only want
456		 * to send it to a file if the status code is 200
457		 */
458		if (statuscode == 200) {
459			/* Generate a file name for the download */
460			fname = strrchr(argv[nres], '/');
461			if (fname == NULL)
462				fname = argv[nres];
463			else
464				fname++;
465			if (strlen(fname) == 0)
466				errx(1, "Cannot obtain file name from %s\n",
467				    argv[nres]);
468
469			fd = open(fname, O_CREAT | O_TRUNC | O_WRONLY, 0644);
470			if (fd == -1)
471				errx(1, "open(%s)", fname);
472		};
473
474		/* Read the message and send data to fd if appropriate */
475		if (chunked) {
476			/* Handle a chunked-encoded entity */
477
478			/* Read chunks */
479			do {
480				error = readln(sd, resbuf, &resbuflen,
481				    &resbufpos);
482				if (error)
483					goto conndied;
484				hln = resbuf + resbufpos;
485				eolp = strstr(hln, "\r\n");
486				resbufpos = (eolp - resbuf) + 2;
487
488				clen = 0;
489				while (isxdigit(*hln)) {
490					if (clen >= OFF_MAX / 16) {
491						/* Nasty people... */
492						goto conndied;
493					}
494					if (isdigit(*hln))
495						clen = clen * 16 + *hln - '0';
496					else
497						clen = clen * 16 + 10 +
498						    tolower(*hln) - 'a';
499					hln++;
500				}
501
502				error = copybytes(sd, fd, clen, resbuf,
503				    &resbuflen, &resbufpos);
504				if (error) {
505					goto conndied;
506				}
507			} while (clen != 0);
508
509			/* Read trailer and final CRLF */
510			do {
511				error = readln(sd, resbuf, &resbuflen,
512				    &resbufpos);
513				if (error)
514					goto conndied;
515				hln = resbuf + resbufpos;
516				eolp = strstr(hln, "\r\n");
517				resbufpos = (eolp - resbuf) + 2;
518			} while (hln != eolp);
519		} else if (contentlength != -1) {
520			error = copybytes(sd, fd, contentlength, resbuf,
521			    &resbuflen, &resbufpos);
522			if (error)
523				goto conndied;
524		} else {
525			/*
526			 * Not chunked, and no content length header.
527			 * Read everything until the server closes the
528			 * socket.
529			 */
530			error = copybytes(sd, fd, OFF_MAX, resbuf,
531			    &resbuflen, &resbufpos);
532			if (error == -1)
533				goto conndied;
534			pipelined = 0;
535		}
536
537		if (fd != -1) {
538			close(fd);
539			fd = -1;
540		}
541
542		fprintf(stderr, "http://%s/%s: %d ", servername, argv[nres],
543		    statuscode);
544		if (statuscode == 200)
545			fprintf(stderr, "OK\n");
546		else if (statuscode < 300)
547			fprintf(stderr, "Successful (ignored)\n");
548		else if (statuscode < 400)
549			fprintf(stderr, "Redirection (ignored)\n");
550		else
551			fprintf(stderr, "Error (ignored)\n");
552
553		/* We've finished this file! */
554		nres++;
555
556		/*
557		 * If necessary, clean up this connection so that we
558		 * can start a new one.
559		 */
560		if (pipelined == 0)
561			goto cleanupconn;
562		continue;
563
564conndied:
565		/*
566		 * Something went wrong -- our connection died, the server
567		 * sent us garbage, etc.  If this happened on the first
568		 * request we sent over this connection, give up.  Otherwise,
569		 * close this connection, open a new one, and reissue the
570		 * request.
571		 */
572		if (nres == firstreq)
573			errx(1, "Connection failure");
574
575cleanupconn:
576		/*
577		 * Clean up our connection and keep on going
578		 */
579		shutdown(sd, SHUT_RDWR);
580		close(sd);
581		sd = -1;
582		if (fd != -1) {
583			close(fd);
584			fd = -1;
585		}
586		if (reqbuf != NULL) {
587			free(reqbuf);
588			reqbuf = NULL;
589		}
590		nreq = nres;
591		res = res0;
592		pipelined = 0;
593		resbufpos = resbuflen = 0;
594		continue;
595	}
596
597	free(resbuf);
598	freeaddrinfo(res0);
599
600	return 0;
601}
602