uudecode.c revision 102890 
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#if 0
41#ifndef lint
42static char sccsid[] = "@(#)uudecode.c	8.2 (Berkeley) 4/2/94";
43#endif /* not lint */
44#endif
45
46#include <sys/cdefs.h>
47__FBSDID("$FreeBSD: head/usr.bin/uudecode/uudecode.c 102890 2002-09-03 09:58:11Z fanf $");
48
49/*
50 * uudecode [file ...]
51 *
52 * create the specified file, decoding as you go.
53 * used with uuencode.
54 */
55#include <sys/param.h>
56#include <sys/socket.h>
57#include <sys/stat.h>
58
59#include <netinet/in.h>
60
61#include <err.h>
62#include <pwd.h>
63#include <resolv.h>
64#include <stdio.h>
65#include <stdlib.h>
66#include <string.h>
67#include <unistd.h>
68
69const char *filename;
70char *outfile;
71int cflag, iflag, oflag, pflag, sflag;
72
73static void usage(void);
74int	decode(void);
75int	decode2(int);
76void	base64_decode(const char *);
77
78int
79main(int argc, char *argv[])
80{
81	int rval, ch;
82
83	while ((ch = getopt(argc, argv, "cio:ps")) != -1) {
84		switch(ch) {
85		case 'c':
86			if (oflag)
87				usage();
88			cflag = 1; /* multiple uudecode'd files */
89			break;
90		case 'i':
91			iflag = 1; /* ask before override files */
92			break;
93		case 'o':
94			if (cflag || pflag || sflag)
95				usage();
96			oflag = 1; /* output to the specified file */
97			sflag = 1; /* do not strip pathnames for output */
98			outfile = optarg; /* set the output filename */
99			break;
100		case 'p':
101			if (oflag)
102				usage();
103			pflag = 1; /* print output to stdout */
104			break;
105		case 's':
106			if (oflag)
107				usage();
108			sflag = 1; /* do not strip pathnames for output */
109			break;
110		default:
111			usage();
112		}
113	}
114        argc -= optind;
115        argv += optind;
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(void)
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(int flag)
155{
156	struct passwd *pw;
157	register int n;
158	register char ch, *p;
159	int base64, ignore, n1;
160	char buf[MAXPATHLEN+1];
161	char buffn[MAXPATHLEN+1]; /* file name buffer */
162	char *mode, *s;
163	void *mode_handle;
164
165	base64 = ignore = 0;
166	/* search for header line */
167	do {
168		if (!fgets(buf, sizeof(buf), stdin)) {
169			if (flag) /* no error */
170				return(0);
171
172			warnx("%s: no \"begin\" line", filename);
173			return(1);
174		}
175	} while (strncmp(buf, "begin", 5) != 0);
176
177	if (strncmp(buf, "begin-base64", 12) == 0)
178		base64 = 1;
179
180	/* Parse the header: begin{,-base64} mode outfile. */
181	s = strtok(buf, " ");
182	if (s == NULL)
183		errx(1, "no mode or filename in input file");
184	s = strtok(NULL, " ");
185	if (s == NULL)
186		errx(1, "no mode in input file");
187	else {
188		mode = strdup(s);
189		if (mode == NULL)
190			err(1, "strdup()");
191	}
192	if (!oflag) {
193		outfile = strtok(NULL, "\r\n");
194		if (outfile == NULL)
195			errx(1, "no filename in input file");
196	}
197
198	if (strlcpy(buf, outfile, sizeof(buf)) >= sizeof(buf))
199		errx(1, "%s: filename too long", outfile);
200	if (!sflag && !pflag) {
201		strlcpy(buffn, buf, sizeof(buffn));
202		if (strrchr(buffn, '/') != NULL)
203			strncpy(buf, strrchr(buffn, '/') + 1, sizeof(buf));
204		if (buf[0] == '\0') {
205			warnx("%s: illegal filename", buffn);
206			return(1);
207		}
208
209		/* handle ~user/file format */
210		if (buf[0] == '~') {
211			if (!(p = index(buf, '/'))) {
212				warnx("%s: illegal ~user", filename);
213				return(1);
214			}
215			*p++ = '\0';
216			if (!(pw = getpwnam(buf + 1))) {
217				warnx("%s: no user %s", filename, buf);
218				return(1);
219			}
220			n = strlen(pw->pw_dir);
221			n1 = strlen(p);
222			if (n + n1 + 2 > MAXPATHLEN) {
223				warnx("%s: path too long", filename);
224				return(1);
225			}
226			bcopy(p, buf + n + 1, n1 + 1);
227			bcopy(pw->pw_dir, buf, n);
228			buf[n] = '/';
229		}
230	}
231
232	/* create output file, set mode */
233	if (pflag)
234		; /* print to stdout */
235
236	else {
237		mode_handle = setmode(mode);
238		if (mode_handle == NULL)
239			err(1, "setmode()");
240		if (iflag && !access(buf, F_OK)) {
241			(void)fprintf(stderr, "not overwritten: %s\n", buf);
242			ignore++;
243		} else if (!freopen(buf, "w", stdout) ||
244		    fchmod(fileno(stdout), getmode(mode_handle, 0) & 0666)) {
245			warn("%s: %s", buf, filename);
246			return(1);
247		}
248		free(mode_handle);
249		free(mode);
250	}
251	strcpy(buffn, buf); /* store file name from header line */
252
253	/* for each input line */
254next:
255	for (;;) {
256		if (!fgets(p = buf, sizeof(buf), stdin)) {
257			warnx("%s: short file", filename);
258			return(1);
259		}
260		if (base64) {
261			if (strncmp(buf, "====", 4) == 0)
262				return (0);
263			base64_decode(buf);
264			goto next;
265		}
266#define	DEC(c)	(((c) - ' ') & 077)		/* single character decode */
267#define IS_DEC(c) ( (((c) - ' ') >= 0) &&  (((c) - ' ') <= 077 + 1) )
268/* #define IS_DEC(c) (1) */
269
270#define OUT_OF_RANGE \
271{	\
272    warnx( \
273"\n\tinput file: %s\n\tencoded file: %s\n\tcharacter out of range: [%d-%d]", \
274 	filename, buffn, 1 + ' ', 077 + ' ' + 1); \
275        return(1); \
276}
277#define PUTCHAR(c) \
278if (!ignore) \
279	putchar(c)
280
281
282		/*
283		 * `n' is used to avoid writing out all the characters
284		 * at the end of the file.
285		 */
286		if ((n = DEC(*p)) <= 0)
287			break;
288		for (++p; n > 0; p += 4, n -= 3)
289			if (n >= 3) {
290				if (!(IS_DEC(*p) && IS_DEC(*(p + 1)) &&
291				     IS_DEC(*(p + 2)) && IS_DEC(*(p + 3))))
292                                	OUT_OF_RANGE
293
294				ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
295				PUTCHAR(ch);
296				ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
297				PUTCHAR(ch);
298				ch = DEC(p[2]) << 6 | DEC(p[3]);
299				PUTCHAR(ch);
300			}
301			else {
302				if (n >= 1) {
303					if (!(IS_DEC(*p) && IS_DEC(*(p + 1))))
304	                                	OUT_OF_RANGE
305					ch = DEC(p[0]) << 2 | DEC(p[1]) >> 4;
306					PUTCHAR(ch);
307				}
308				if (n >= 2) {
309					if (!(IS_DEC(*(p + 1)) &&
310						IS_DEC(*(p + 2))))
311		                                OUT_OF_RANGE
312
313					ch = DEC(p[1]) << 4 | DEC(p[2]) >> 2;
314					PUTCHAR(ch);
315				}
316				if (n >= 3) {
317					if (!(IS_DEC(*(p + 2)) &&
318						IS_DEC(*(p + 3))))
319		                                OUT_OF_RANGE
320					ch = DEC(p[2]) << 6 | DEC(p[3]);
321					PUTCHAR(ch);
322				}
323			}
324	}
325	if (fgets(buf, sizeof(buf), stdin) == NULL ||
326	    (strcmp(buf, "end") && strcmp(buf, "end\n") &&
327	     strcmp(buf, "end\r\n"))) {
328		warnx("%s: no \"end\" line", filename);
329		return(1);
330	}
331	return(0);
332}
333
334void
335base64_decode(const char *stream)
336{
337	unsigned char out[MAXPATHLEN * 4];
338	int rv;
339
340	if (index(stream, '\r') != NULL)
341		*index(stream, '\r') = '\0';
342	if (index(stream, '\n') != NULL)
343		*index(stream, '\n') = '\0';
344	rv = b64_pton(stream, out, (sizeof(out) / sizeof(out[0])));
345	if (rv == -1)
346		errx(1, "b64_pton: error decoding base64 input stream");
347	fwrite(out, 1, rv, stdout);
348}
349
350static void
351usage(void)
352{
353	(void)fprintf(stderr,
354"usage: uudecode [-cips] [file ...]\n"
355"       uudecode [-i] -o output_file [file]\n"
356"       b64decode [-cips] [file ...]\n"
357"       b64decode [-i] -o output_file [file]\n");
358	exit(1);
359}
360