uudecode.c revision 96386 
1/*-
2 * Copyright (c) 1983, 1993
3 *	The Regents of the University of California.  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 * 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 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1983, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "@(#)uudecode.c	8.2 (Berkeley) 4/2/94";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/usr.bin/uudecode/uudecode.c 96386 2002-05-11 03:29:04Z alfred $";
46#endif /* not lint */
47
48/*
49 * uudecode [file ...]
50 *
51 * create the specified file, decoding as you go.
52 * used with uuencode.
53 */
54#include <sys/param.h>
55#include <sys/socket.h>
56#include <sys/stat.h>
57
58#include <netinet/in.h>
59
60#include <err.h>
61#include <pwd.h>
62#include <resolv.h>
63#include <stdio.h>
64#include <stdlib.h>
65#include <string.h>
66#include <unistd.h>
67
68const char *filename;
69char *outfile;
70int cflag, iflag, oflag, pflag, sflag;
71
72static void usage(void);
73int	decode(void);
74int	decode2(int);
75void	base64_decode(const char *);
76
77int
78main(int argc, char *argv[])
79{
80	int rval, ch;
81
82	while ((ch = getopt(argc, argv, "cio:ps")) != -1) {
83		switch(ch) {
84		case 'c':
85			if (oflag)
86				usage();
87			cflag = 1; /* multiple uudecode'd files */
88			break;
89		case 'i':
90			iflag = 1; /* ask before override files */
91			break;
92		case 'o':
93			if (cflag || pflag || sflag)
94				usage();
95			oflag = 1; /* output to the specified file */
96			sflag = 1; /* do not strip pathnames for output */
97			outfile = optarg; /* set the output filename */
98			break;
99		case 'p':
100			if (oflag)
101				usage();
102			pflag = 1; /* print output to stdout */
103			break;
104		case 's':
105			if (oflag)
106				usage();
107			sflag = 1; /* do not strip pathnames for output */
108			break;
109		default:
110			usage();
111		}
112	}
113        argc -= optind;
114        argv += optind;
115
116
117	if (*argv) {
118		rval = 0;
119		do {
120			if (!freopen(filename = *argv, "r", stdin)) {
121				warn("%s", *argv);
122				rval = 1;
123				continue;
124			}
125			rval |= decode();
126		} while (*++argv);
127	} else {
128		filename = "stdin";
129		rval = decode();
130	}
131	exit(rval);
132}
133
134int
135decode ()
136{
137	int flag;
138
139	/* decode only one file per input stream */
140	if (!cflag)
141		return(decode2(0));
142
143	/* multiple uudecode'd files */
144	for (flag = 0; ; flag++)
145		if (decode2(flag))
146			return(1);
147		else if (feof(stdin))
148			break;
149
150	return(0);
151}
152
153int
154decode2(flag)
155	int flag;
156{
157	struct passwd *pw;
158	register int n;
159	register char ch, *p;
160	int base64, ignore, n1;
161	char buf[MAXPATHLEN+1];
162	char buffn[MAXPATHLEN+1]; /* file name buffer */
163	char *mode, *s;
164	void *mode_handle;
165
166	base64 = ignore = 0;
167	/* search for header line */
168	do {
169		if (!fgets(buf, sizeof(buf), stdin)) {
170			if (flag) /* no error */
171				return(0);
172
173			warnx("%s: no \"begin\" line", filename);
174			return(1);
175		}
176	} while (strncmp(buf, "begin", 5) != 0);
177
178	if (strncmp(buf, "begin-base64", 12) == 0)
179		base64 = 1;
180
181	/* Parse the header: begin{,-base64} mode outfile. */
182	s = strtok(buf, " ");
183	if (s == NULL)
184		errx(1, "no mode or filename in input file");
185	s = strtok(NULL, " ");
186	if (s == NULL)
187		errx(1, "no mode in input file");
188	else {
189		mode = strdup(s);
190		if (mode == NULL)
191			err(1, "strdup()");
192	}
193	if (!oflag) {
194		outfile = strtok(NULL, "\r\n");
195		if (outfile == NULL)
196			errx(1, "no filename in input file");
197	}
198
199	if (strlcpy(buf, outfile, sizeof(buf)) >= sizeof(buf))
200		errx(1, "%s: filename too long", outfile);
201	if (!sflag && !pflag) {
202		strlcpy(buffn, buf, sizeof(buffn));
203		if (strrchr(buffn, '/') != NULL)
204			strncpy(buf, strrchr(buffn, '/') + 1, sizeof(buf));
205		if (buf[0] == '\0') {
206			warnx("%s: illegal filename", buffn);
207			return(1);
208		}
209
210		/* handle ~user/file format */
211		if (buf[0] == '~') {
212			if (!(p = index(buf, '/'))) {
213				warnx("%s: illegal ~user", filename);
214				return(1);
215			}
216			*p++ = '\0';
217			if (!(pw = getpwnam(buf + 1))) {
218				warnx("%s: no user %s", filename, buf);
219				return(1);
220			}
221			n = strlen(pw->pw_dir);
222			n1 = strlen(p);
223			if (n + n1 + 2 > MAXPATHLEN) {
224				warnx("%s: path too long", filename);
225				return(1);
226			}
227			bcopy(p, buf + n + 1, n1 + 1);
228			bcopy(pw->pw_dir, buf, n);
229			buf[n] = '/';
230		}
231	}
232
233	/* create output file, set mode */
234	if (pflag)
235		; /* print to stdout */
236
237	else {
238		mode_handle = setmode(mode);
239		if (mode_handle == NULL)
240			err(1, "setmode()");
241		if (iflag && !access(buf, F_OK)) {
242			(void)fprintf(stderr, "not overwritten: %s\n", buf);
243			ignore++;
244		} else if (!freopen(buf, "w", stdout) ||
245		    fchmod(fileno(stdout), getmode(mode_handle, 0) & 0666)) {
246			warn("%s: %s", buf, filename);
247			return(1);
248		}
249		free(mode_handle);
250		free(mode);
251	}
252	strcpy(buffn, buf); /* store file name from header line */
253
254	/* for each input line */
255next:
256	for (;;) {
257		if (!fgets(p = buf, sizeof(buf), stdin)) {
258			warnx("%s: short file", filename);
259			return(1);
260		}
261		if (base64) {
262			if (strncmp(buf, "====", 4) == 0)
263				return (0);
264			base64_decode(buf);
265			goto next;
266		}
267#define	DEC(c)	(((c) - ' ') & 077)		/* single character decode */
268#define IS_DEC(c) ( (((c) - ' ') >= 0) &&  (((c) - ' ') <= 077 + 1) )
269/* #define IS_DEC(c) (1) */
270
271#define OUT_OF_RANGE \
272{	\
273    warnx( \
274"\n\tinput file: %s\n\tencoded file: %s\n\tcharacter out of range: [%d-%d]", \
275 	filename, buffn, 1 + ' ', 077 + ' ' + 1); \
276        return(1); \
277}
278#define PUTCHAR(c) \
279if (!ignore) \
280	putchar(c)
281
282
283		/*
284		 * `n' is used to avoid writing out all the characters
285		 * at the end of the file.
286		 */
287		if ((n = DEC(*p)) <= 0)
288			break;
289		for (++p; n > 0; p += 4, n -= 3)
290			if (n >= 3) {
291				if (!(IS_DEC(*p) && IS_DEC(*(p + 1)) &&
292				     IS_DEC(*(p + 2)) && IS_DEC(*(p + 3))))
293                                	OUT_OF_RANGE
294
295				ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
296				PUTCHAR(ch);
297				ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
298				PUTCHAR(ch);
299				ch = DEC(p[2]) << 6 | DEC(p[3]);
300				PUTCHAR(ch);
301
302			}
303			else {
304				if (n >= 1) {
305					if (!(IS_DEC(*p) && IS_DEC(*(p + 1))))
306	                                	OUT_OF_RANGE
307					ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
308					PUTCHAR(ch);
309				}
310				if (n >= 2) {
311					if (!(IS_DEC(*(p + 1)) &&
312						IS_DEC(*(p + 2))))
313		                                OUT_OF_RANGE
314
315					ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
316					PUTCHAR(ch);
317				}
318				if (n >= 3) {
319					if (!(IS_DEC(*(p + 2)) &&
320						IS_DEC(*(p + 3))))
321		                                OUT_OF_RANGE
322					ch = DEC(p[2]) << 6 | DEC(p[3]);
323					PUTCHAR(ch);
324				}
325			}
326	}
327	if (fgets(buf, sizeof(buf), stdin) == NULL ||
328	    (strcmp(buf, "end") && strcmp(buf, "end\n") &&
329	     strcmp(buf, "end\r\n"))) {
330		warnx("%s: no \"end\" line", filename);
331		return(1);
332	}
333	return(0);
334}
335
336void
337base64_decode(stream)
338	const char *stream;
339{
340	unsigned char out[MAXPATHLEN * 4];
341	int rv;
342
343	if (index(stream, '\r') != NULL)
344		*index(stream, '\r') = '\0';
345	if (index(stream, '\n') != NULL)
346		*index(stream, '\n') = '\0';
347	rv = b64_pton(stream, out, (sizeof(out) / sizeof(out[0])));
348	if (rv == -1)
349		errx(1, "b64_pton: error decoding base64 input stream");
350	fwrite(out, 1, rv, stdout);
351}
352
353static void
354usage()
355{
356	(void)fprintf(stderr, "usage: uudecode [-cips] [file ...]\n");
357	(void)fprintf(stderr, "usage: uudecode [-i] -o output_file [file]\n");
358	exit(1);
359}
360