uudecode.c revision 92922 
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 92922 2002-03-22 01:42:45Z imp $";
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(argc, argv)
79	int argc;
80	char *argv[];
81{
82	int rval, ch;
83
84	while ((ch = getopt(argc, argv, "cio:ps")) != -1) {
85		switch(ch) {
86		case 'c':
87			if (oflag)
88				usage();
89			cflag = 1; /* multiple uudecode'd files */
90			break;
91		case 'i':
92			iflag = 1; /* ask before override files */
93			break;
94		case 'o':
95			if (cflag || pflag || sflag)
96				usage();
97			oflag = 1; /* output to the specified file */
98			sflag = 1; /* do not strip pathnames for output */
99			outfile = optarg; /* set the output filename */
100			break;
101		case 'p':
102			if (oflag)
103				usage();
104			pflag = 1; /* print output to stdout */
105			break;
106		case 's':
107			if (oflag)
108				usage();
109			sflag = 1; /* do not strip pathnames for output */
110			break;
111		default:
112			usage();
113		}
114	}
115        argc -= optind;
116        argv += optind;
117
118
119	if (*argv) {
120		rval = 0;
121		do {
122			if (!freopen(filename = *argv, "r", stdin)) {
123				warn("%s", *argv);
124				rval = 1;
125				continue;
126			}
127			rval |= decode();
128		} while (*++argv);
129	} else {
130		filename = "stdin";
131		rval = decode();
132	}
133	exit(rval);
134}
135
136int
137decode ()
138{
139	int flag;
140
141	/* decode only one file per input stream */
142	if (!cflag)
143		return(decode2(0));
144
145	/* multiple uudecode'd files */
146	for (flag = 0; ; flag++)
147		if (decode2(flag))
148			return(1);
149		else if (feof(stdin))
150			break;
151
152	return(0);
153}
154
155int
156decode2(flag)
157	int flag;
158{
159	struct passwd *pw;
160	register int n;
161	register char ch, *p;
162	int base64, ignore, n1;
163	char buf[MAXPATHLEN+1];
164	char buffn[MAXPATHLEN+1]; /* file name buffer */
165	char *mode, *s;
166	void *mode_handle;
167
168	base64 = ignore = 0;
169	/* search for header line */
170	do {
171		if (!fgets(buf, sizeof(buf), stdin)) {
172			if (flag) /* no error */
173				return(0);
174
175			warnx("%s: no \"begin\" line", filename);
176			return(1);
177		}
178	} while (strncmp(buf, "begin", 5) != 0);
179
180	if (strncmp(buf, "begin-base64", 12) == 0)
181		base64 = 1;
182
183	/* Parse the header: begin{,-base64} mode outfile. */
184	s = strtok(buf, " ");
185	if (s == NULL)
186		errx(1, "no mode or filename in input file");
187	s = strtok(NULL, " ");
188	if (s == NULL)
189		errx(1, "no mode in input file");
190	else {
191		mode = strdup(s);
192		if (mode == NULL)
193			err(1, "strdup()");
194	}
195	if (!oflag) {
196		outfile = strtok(NULL, "\r\n");
197		if (outfile == NULL)
198			errx(1, "no filename in input file");
199	}
200
201	if (strlcpy(buf, outfile, sizeof(buf)) >= sizeof(buf))
202		errx(1, "%s: filename too long", outfile);
203	if (!sflag && !pflag) {
204		strlcpy(buffn, buf, sizeof(buffn));
205		if (strrchr(buffn, '/') != NULL)
206			strncpy(buf, strrchr(buffn, '/') + 1, sizeof(buf));
207		if (buf[0] == '\0') {
208			warnx("%s: illegal filename", buffn);
209			return(1);
210		}
211
212		/* handle ~user/file format */
213		if (buf[0] == '~') {
214			if (!(p = index(buf, '/'))) {
215				warnx("%s: illegal ~user", filename);
216				return(1);
217			}
218			*p++ = '\0';
219			if (!(pw = getpwnam(buf + 1))) {
220				warnx("%s: no user %s", filename, buf);
221				return(1);
222			}
223			n = strlen(pw->pw_dir);
224			n1 = strlen(p);
225			if (n + n1 + 2 > MAXPATHLEN) {
226				warnx("%s: path too long", filename);
227				return(1);
228			}
229			bcopy(p, buf + n + 1, n1 + 1);
230			bcopy(pw->pw_dir, buf, n);
231			buf[n] = '/';
232		}
233	}
234
235	/* create output file, set mode */
236	if (pflag)
237		; /* print to stdout */
238
239	else {
240		mode_handle = setmode(mode);
241		if (mode_handle == NULL)
242			err(1, "setmode()");
243		if (iflag && !access(buf, F_OK)) {
244			(void)fprintf(stderr, "not overwritten: %s\n", buf);
245			ignore++;
246		} else if (!freopen(buf, "w", stdout) ||
247		    fchmod(fileno(stdout), getmode(mode_handle, 0) & 0666)) {
248			warn("%s: %s", buf, filename);
249			return(1);
250		}
251		free(mode_handle);
252		free(mode);
253	}
254	strcpy(buffn, buf); /* store file name from header line */
255
256	/* for each input line */
257next:
258	for (;;) {
259		if (!fgets(p = buf, sizeof(buf), stdin)) {
260			warnx("%s: short file", filename);
261			return(1);
262		}
263		if (base64) {
264			if (strncmp(buf, "====", 4) == 0)
265				return (0);
266			base64_decode(buf);
267			goto next;
268		}
269#define	DEC(c)	(((c) - ' ') & 077)		/* single character decode */
270#define IS_DEC(c) ( (((c) - ' ') >= 0) &&  (((c) - ' ') <= 077 + 1) )
271/* #define IS_DEC(c) (1) */
272
273#define OUT_OF_RANGE \
274{	\
275    warnx( \
276"\n\tinput file: %s\n\tencoded file: %s\n\tcharacter out of range: [%d-%d]", \
277 	filename, buffn, 1 + ' ', 077 + ' ' + 1); \
278        return(1); \
279}
280#define PUTCHAR(c) \
281if (!ignore) \
282	putchar(c)
283
284
285		/*
286		 * `n' is used to avoid writing out all the characters
287		 * at the end of the file.
288		 */
289		if ((n = DEC(*p)) <= 0)
290			break;
291		for (++p; n > 0; p += 4, n -= 3)
292			if (n >= 3) {
293				if (!(IS_DEC(*p) && IS_DEC(*(p + 1)) &&
294				     IS_DEC(*(p + 2)) && IS_DEC(*(p + 3))))
295                                	OUT_OF_RANGE
296
297				ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
298				PUTCHAR(ch);
299				ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
300				PUTCHAR(ch);
301				ch = DEC(p[2]) << 6 | DEC(p[3]);
302				PUTCHAR(ch);
303
304			}
305			else {
306				if (n >= 1) {
307					if (!(IS_DEC(*p) && IS_DEC(*(p + 1))))
308	                                	OUT_OF_RANGE
309					ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
310					PUTCHAR(ch);
311				}
312				if (n >= 2) {
313					if (!(IS_DEC(*(p + 1)) &&
314						IS_DEC(*(p + 2))))
315		                                OUT_OF_RANGE
316
317					ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
318					PUTCHAR(ch);
319				}
320				if (n >= 3) {
321					if (!(IS_DEC(*(p + 2)) &&
322						IS_DEC(*(p + 3))))
323		                                OUT_OF_RANGE
324					ch = DEC(p[2]) << 6 | DEC(p[3]);
325					PUTCHAR(ch);
326				}
327			}
328	}
329	if (fgets(buf, sizeof(buf), stdin) == NULL ||
330	    (strcmp(buf, "end") && strcmp(buf, "end\n") &&
331	     strcmp(buf, "end\r\n"))) {
332		warnx("%s: no \"end\" line", filename);
333		return(1);
334	}
335	return(0);
336}
337
338void
339base64_decode(stream)
340	const char *stream;
341{
342	unsigned char out[MAXPATHLEN * 4];
343	int rv;
344
345	rv = b64_pton(stream, out, (sizeof(out) / sizeof(out[0])));
346	if (rv == -1)
347		errx(1, "b64_pton: error decoding base64 input stream");
348	printf("%s", out);
349}
350
351static void
352usage()
353{
354	(void)fprintf(stderr, "usage: uudecode [-cips] [file ...]\n");
355	(void)fprintf(stderr, "usage: uudecode [-i] -o output_file [file]\n");
356	exit(1);
357}
358